Article

Biological effect of far-infrared therapy on increasing skin microcirculation in rats

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Abstract

Insufficient microcirculation of skin leads to acute and chronic tissue ischemia in cases of trauma, reconstructive surgery, diabetes mellitus and peripheral arterial occlusive disease. The autonomic nervous system and nitric oxide (NO) play important roles in maintaining blood perfusion of the skin. Far-infrared (FIR) therapy provides low energy of light emitted from an artificial radiator and has been used to treat many vascular-related disorders. Nevertheless, the mechanisms through which FIR works remain unclear. The present study aims to test the hypothesis that the effect of FIR is through increasing skin microcirculation by a mechanism other than its thermal effect. Sixty rats were used in the present study. A WS TY301 FIR emitter was placed 20 cm above the rats. Skin temperature and blood flow were continuously measured by a K-type thermocouple. Under laboratory control, the abdominal skin temperature steadily increased from 38-39 degrees C, and was kept at constant temperature. Skin microcirculation was measured with a continuous laser Doppler flowmeter. There was no significant change of skin blood flow during FIR treatment. Skin blood flow increased significantly soon after the removal of the FIR emitter. The stimulating effect on skin blood flow was more significant in the rats treated with FIR for 45 min and could be sustained as long as 60 min. These findings suggested a non-thermic biological effect of FIR on skin microcirculation. The promotive effect of FIR on increasing skin blood flow was not influenced by pretreatment of APP (atropine, propranolol and phentolamine), but was suppressed by pretreatment with NG-nitro-L-arginine methyl ester (an endothelial nitric oxide synthase inhibitor). In conclusion, FIR therapy exerts a NO-related biological effect to increase skin microcirculation in rats. This might bring into perspective the clinical application of FIR to treat ischemic disease by augmenting L-arginine/NO pathway.

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... [10] The therapeutic effects of FIR are both thermal and nonthermal, including increased skin temperature, vasodilation and increased blood flow to the treated area, increased extension of collagen tissues, improved endothelial function, and improved circulation. [10,18,19] These effects cumulatively result in tissue healing and improved quality of life. ...
... Previous studies have recommended that the appropriate distance for FIR irradiation treatment be 20 to 30 cm and the duration 40 minutes. [11,[15][16][17][18] In the pilot test, the FSST was maintained at 34.8°C to 37.7°C in the 20 cm group and 33.5°C to 35.2°C in the 30 cm group. It was confirmed in the 20 cm group that the hyperthermia effect (37.5°C-38.3°C) ...
... This effect has been quantified in dermal microperfusion via upregulation of endothelial nitric oxide synthase action in vascular endothelium in rats. [18] This results in increased skin temperature, and increased nutrient and oxygen delivery, which promotes tissue healing. [10,11] Research literature has shown that most elderly people suffer from poor lower extremity circulation. ...
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Background: Far-infrared irradiation (FIR) is used in the medical field to improve wound healing, hemodialysis with peripheral artery occlusive disease, and osteoarthritis but seldom used in ameliorating poor lower extremity circulation. The purpose of this study was to evaluate the effect of FIR on changes in foot skin surface temperature (FSST) and autonomic nerve system (ANS) activity to evaluate its effectiveness in improving lower limb circulation. Methods: A randomized controlled study was conducted. Subjects (n = 44), all over the age of 50 years and satisfying the inclusion criteria, were randomly allocated into 2 groups. The intervention group received FIR on a lower limb for 40 minutes and the control group received no intervention. Left big toe (LBT), right big toe (RBT), left foot dorsal (LFD), right foot dorsal (RFD) surface skin temperature, autonomic nervous activity, and blood pressure were assessed. Results: The main results were skin surface temperature at the LBT increased from 30.8 ± 0.4°C to 34.8 ± 0.4°C, at RBT increased from 29.6 ± 0.4°C to 35.3 ± 0.4°C and LFD increased from 31.9 ± 0.3°C to 36.4 ± 0.4°C, RFD increased from 30.7 ± 0.3°C to 37.7 ± 0.2°C. FIR caused a significant increase of the FSST ranging in a 4°C to 7°C increase after 40 minutes irradiation (P < .001). The ANS low-frequency (LF) and high-frequency (HF) activity showed a statistically significant increase in the FIR group (P < .05) but not the LF/HF ratio. Conclusion: FIR significantly increased the FSST from between 4°C and 7°C after 40 minutes irradiation, which might improve lower extremity circulation and regulation of ANS activity.
... Far-infrared radiation (FIR; l ¼ 3-100 μm), a subdivision of the electromagnetic spectrum, has been investigated for its biological effects. FIR therapy, which provides low-energy light from an artificial radiator, has been used as treatment for various vascular-related disorders (Yu et al., 2006). Health care providers have applied FIR therapy widely in clinical treatments (Shui et al., 2015;Yueh et al., 2014), and technological advances have provided new strategies for delivering FIR to the human body. ...
... Research has shown that, soon after the removal of the FIR emitter, blood flow in the skin increases significantly. In one study, a 45-min treatment with FIR had stimulating effects on skin blood flow in rats, and the increased flow was sustained for as long as 60 min (Yu et al., 2006). Several research studies have shown that FIR photons releasing thermal energy to tissue molecules aid in vessel dilation and improve peripheral blood circulation. ...
... FIR therapy is known to inhibit vascular inflammation (Chang, 2018;Yu et al., 2006) by inducing hemeoxygenase-1 (HO-1) synthesis (Lin et al., 2008), which leads to increased skin microcirculation and activates and restores endothelial nitric oxide synthase (eNOS; Gribbe et al., 2007;Yu et al., 2006), which regulates vascular tone and permeability. The therapy also inhibits interleukin (IL) 6 and tumor necrosis factor (TNF) a response to reduce vessel inflammation and increase angiogenesis (Lin et al., 2008). ...
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Background Far-infrared radiation (FIR) therapy improves vessel dilation, circulation, vessel endothelial function, and angiogenesis and reduces atherosclerosis. However, evidence of FIR therapy’s effects on foot circulation among diabetic patients undergoing hemodialysis is scarce. Aim To determine whether FIR therapy improves foot circulation in diabetic patients undergoing hemodialysis. Design Quasi-experimental. Methods In June to November 2017, diabetic patients undergoing hemodialysis ( N = 58) at a hemodialysis center in northern Taiwan were divided into two groups: the experimental group ( n = 31) received FIR therapy to the bilateral dorsalis pedis artery (40 min/session, 3 times/week for 6 months) and the control group ( n = 27) received conventional dialysis care. Paired t test, independent samples t test, two-proportion Z test, and repeated-measures analysis of covariance were performed to compare changes from baseline to the end of the 6-month intervention between the groups. Results Significant positive effects of FIR therapy on temperature, pulse, and blood flow of the dorsalis pedis artery were observed. Sensitivity to pain, tactility, and pressure also improved significantly in the experimental group. The Edinburgh Claudication Questionnaire revealed that the experimental group had reductions in subjective experiences of soreness, tingling, and coldness in the feet. Conclusion The findings of significant improvements to objective and subjective measures of blood flow and neural function in the experimental group indicate that FIR therapy improves blood circulation to the feet. This therapy thus has great potential to be an effective adjuvant treatment for patients with diabetes mellitus undergoing hemodialysis.
... In fact, human body utilize it every day in order for the natural physiological functions to perform well including treatment of several vascular-related disorders. While the FIR technology has been extensively used in health improvement [4][5][6] and food preservation, the precise and concrete mechanisms of producing hyperthermic activity and other biological functions remains unclear [7][8][9]. ...
... FIR as a form of medical therapy is a safe, noninvasive and convenient therapeutic modality, which is known to improve both blood flow and endothelial function. It can be further considered as a type of physiotherapy since it can penetrate up to 4 cm (~1.5 inches) beneath the skin and generates effects in the human body either thermal or non-thermal [7,[10][11][12]. ...
... This can be possibly due to the synthesis, utilization and enhancement of the natural physiological factors induced by the FIR which led to the increase in blood flow. This mechanism is seen to be processed by the nitric oxide action of the autonomic nervous system [7]. ...
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COVID-19 virus causes mass death worldwide which is facing an unending battle that needs unconventional evidence in complementary and alternative medicine. This review aims to elucidate the possible health benefit of far infrared from Nuga Bed/Mat® along with its heat produced and the application of castor oil pack that has antiviral property in the management of coronavirus infection. Far infrared radiation from Nuga Bed/Mat® has low wavelength and is perceived as heat by the thermoreceptors of the human body. The presence of heat from the Nuga Bed/Mat® coming from the far infrared radiation gives sufficient health benefits including detoxification, pain relief, reduction of muscle tension, relaxation, improved circulation, boosting of the immune system and lowering of blood pressure. SARS-CoV-2 infection manifests inflammation of the vascular endothelium which prevents proper circulation of the blood and can further progress to blood clotting. Treatment with Far infrared radiation for 40 minutes to 2 hours causes the stimulation of HO-1 protein that induces anti-inflammatory activity on the vascular endothelium and other sites of inflammation. Hence, improved blood flow can be expected after an exposure with far infrared radiation. With the added castor oil, spread on the specific site which has a corresponding antiviral property, the possibility of alleviation from the symptoms associated with coronavirus infection can give a light of hope as an alternative remedy.
... The energy produced is divided into two categories: thermal and non-thermal, according to the form the energy takes [21]. FIR was able to increase skin blood flow using thermal therapy in mice and rats [22,23]. Akasaki et al. (2006) found that FIR promotes angiogenesis in mice through a non-thermal effect; and that FIR inhibited IL-6 and TNF-α activity in mice with peritonitis [24]. ...
... In recent years, more studies confirmed and elucidated the effects of far-infrared rays in the human body. For example, FIR has been shown to promote blood circulation [23,25], relieve fatigue and pain [26,27], and promote wound healing [25,[28][29][30]. ...
... Far-infrared radiation therapy can promote hemeoxygenase-1 (HO-1) and endothelial nitric oxide synthase (eNOS) generated by the L-arginine/nitric oxide pathway, reducing inflammation through the inhibition of intimal hyperplasia and reducing oxidation. It can even stimulate the inhibition of TNF-α to produce anti-inflammatory effects [23,29,32,[34][35][36][37]. Although the mechanisms involved in FIR are not clear, various studies indicate that far-infrared rays can promote the proliferation of bone marrow stem cells and keratinocytes through the CXCR4/ERK or Notch1/Twist pathways [31,[38][39][40]. ...
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The use of peritoneal dialysis in end-stage renal disease is increasing in clinical practice. The main purpose of this study was to evaluate the effect of far-infrared radiation therapy on inflammation and the cellular immunity of patients undergoing peritoneal dialysis. We recruited 56 patients undergoing peritoneal dialysis, and we included 32 patients for the experimental group and 24 patients from the control group in the final analysis. The experimental evaluation in our study was as follows: (1) We used abdominal computed tomography to explore the changes in abdominal blood vessels. (2) We compared the effects of peritoneal dialysis using blood glucose, HbAlC, albumin, urea nitrogen, creatinine, white blood cells, hs-CRP; peritoneal Kt/V of peritoneal function, and eGFR. (3) We compared the cytokines’ concentrations in the two groups while controlling for the other cytokines. Results and Discussion: (1) There was no significant difference in the abdominal blood vessels of the experimental group relative to the control group according to abdominal CT over the 6 months. (2) Our study demonstrates statistically significant effects of FIR therapy on the following parameters: creatinine (p = 0.039 *) and hs-CRP (p < 0.001 **) levels decreased significantly, and eGFR (p = 0.043 *), glucose (p < 0.001 **), and albumin (p = 0.048 *) levels increased significantly. Our study found that in the experimental group, creatinine and hs-CRP levels decreased significantly due to FIR therapy for 6 months. However, our study also found that the glucose level was significantly different after FIR therapy for 6 months. Peritoneal dialysis combined with FIR can reduce the side effects of the glucose in the dialysis buffer, which interferes with peritoneal inflammation and peritoneal mesothelial cell fibrosis. (3) In addition, we also found that no statistically significant difference in any inflammatory cytokine after FIR therapy. IFN-γ (p = 0.124), IL-12p70 (p = 0.093), IL-18 (p = 0.213), and TNF-α (p = 0.254) did not exhibit significant improvements after peritoneal dialysis with FIR treatment over 6 months. Conclusions: We found that the effectiveness of peritoneal dialysis was improved significantly with FIR therapy, and significant improvements in the peritoneal permeability and inflammatory response were observed.
... In the electromagnetic spectrum, FIR has a wavelength of 15 µm to 1 mm, which falls within the infrared wavelength range (750 nm-1 mm) [9]. FIR is beneficial for medical treatment because in the IR wavelength, only FIR produces gentle radiant heat and has high penetrability (almost 4 cm) that can be sensed by local thermoreceptors of skin [10,11]. As FIR can produce thermal effects on the body, it can be utilized to elevate local tissue temperature that leads to blood vessel dilation; this mechanism could be used to improve blood circulation in active areas of the body [12]. ...
... The IIEF-5 is an abridged, five-item version of the 15-item IIEF that focuses on erectile function and intercourse satisfaction [60]. The IIEF-5 score, ranging from 5-25 points, classifies ED into the following five categories: none (22)(23)(24)(25), mild (17)(18)(19)(20)(21), mild to moderate (12)(13)(14)(15)(16), (8)(9)(10)(11), and severe (5-7). The QEQ is a questionnaire that assesses satisfaction in the quality of erections that were attained and maintained and can differentiate between all ED severity groups as categorized by the IIEF-5 questionnaire scores [61]. ...
... The QEQ is evaluated as a final score that ranges from 0 to 100 points. This score is transformed on a scale of 1-30 to define the degree of ED as follows: normal (26)(27)(28)(29)(30), mild (22)(23)(24)(25), mild to moderate (17)(18)(19)(20)(21), moderate (11)(12)(13)(14)(15)(16), and severe (1-10). The PEDT is a questionnaire that standardizes and captures five main elements of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) in diagnosing premature ejaculation, including control, frequency, minimal sexual stimulation, distress, and interpersonal difficulty [62]. ...
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By continuously enhancing the blood flow, far-infrared (FIR) textile is anticipated to be a potential non-pharmacological therapy in patients with peripheral vascular disorders, for instance, patients with end-stage renal disease (ESRD) undergoing hemodialysis (HD) and experiencing vasculogenic erectile dysfunction (VED). Hence, we manufactured a novel polymer composite, namely, germanium-titanium-π (Ge-Ti-π) textile and aimed to evaluate its characteristics and quality. We also investigated the immediate and long-term effects of the textile on patients with ESRD undergoing HD and experiencing VED. The Ge-Ti-π textile was found to have 0.93 FIR emissivity, 3.05 g/d strength, and 18.98% elongation. The results also showed a 51.6% bacteria reduction and negative fungal growth. On application in patients receiving HD, the Ge-Ti-π textile significantly reduced the limb numbness/pain (p < 0.001) and pain score on the visual analog scale (p < 0.001). Moreover, the Doppler ultrasound assessment data indicated a significant enhancement of blood flow in the right hand after 1 week of Ge-Ti-π textile treatment (p < 0.041). In VED patients, the Ge-Ti-π underpants treatment significantly improved the quality of sexual function and increased the average penile blood flow velocity after 3 months of the treatment. Our study suggests that the Ge-Ti-π textile could be beneficial for patients with blood circulation disorders.
... It is a source of high performance far-infrared rays that mainly exhibit thermal effects. FIR increases microvascular dilation and vascular flow volume and causes a slight elevation in the regional tissue temperature, reducing the sizes of water clusters by weakening the hydrogen bonds in water molecules [8][9][10][11][12][13]. Several studies have shown that far-infrared ray treatment promotes microcirculation and accelerates wound healing by increasing fibroblast proliferation, enhancing immunity by activating leukocytes and phagocytic processes, promoting sleep, and playing a prominent role in ameliorating aging processes [7,9,[14][15][16]. ...
... FIR has been reported to increase microvascular dilation and tissue temperature by weakening the hydrogen bonds of water molecules by emitting at a wavelengths of 4-16 μm as well as increasing NO production [7][8][9][10][11][12][13]. FIR also accelerates wound healing by increasing fibroblast proliferation, enhancing immunity by activating leukocytes and phagocytic processes, promoting sleep, and ameliorating the aging process [7,9,15,16]. ...
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Thermal conditions are an important environmental factor in maintaining healthy pigs because they affect feed intake, growth efficiency, reproduction and immune responses in pigs. RAVI, a regenerative far-infrared heating system, can effect pig production by emitting an optimal far-infrared wavelength. Far-infrared radiation has been reported to increase microvascular dilation and vascular flow volume. The purpose of this study was to evaluate the immunobiological differences between pigs raised with the RAVI system and the gasoline heater system. Twenty-six-week-old weaned pigs were raised in two rooms that were equipped with a RAVI system or a gasoline heater for 8 weeks. A porcine atrophic rhinitis vaccine was administered after two weeks and transcriptome analysis in whole blood were analyzed at 2-week intervals. Signaling pathway analyses of the RAVI group at 8 weeks showed the activation of pathways related to nitric oxide (NO) production. This suggests that the application of RAVI might induce the production of NO and iNOS, which are important for increasing the immune activity. Similar to the result of microarray, phenotypic changes were also observed at a later period of the experiment. The increase in body weight in the RAVI group was significantly higher than the gasoline heater group at 8 weeks. The antibody titer against the vaccine in the RAVI group was also higher than that the gasoline heater group at 4 weeks and 8 weeks. This evaluation of the use of a far-infrared heating system with pigs will be helpful for applications in the pig farm industry and pig welfare.
... In the medical field, FIR is usually used for patients with lymphedema and vascular disease [8,16]. Its surgical application has been actively investigated for plastic surgery and oral-maxillofacial surgery [17,18]. In plastic surgery, FIR has been proven to induce wound healing by increasing skin microcirculation in rats undergoing flap treatment [17]. ...
... Its surgical application has been actively investigated for plastic surgery and oral-maxillofacial surgery [17,18]. In plastic surgery, FIR has been proven to induce wound healing by increasing skin microcirculation in rats undergoing flap treatment [17]. In oral-maxillofacial surgery, FIR has been proven to aid wound healing after tooth extraction [18,19]. ...
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Background: The effects of far-infrared radiation (FIR) on the treatment of rotator cuff diseases remains unknown. We evaluated the safety and efficacy of FIR after arthroscopic rotator cuff repair with regard to postoperative pain and healing. Methods: This prospective randomized comparative study included 38 patients who underwent arthroscopic rotator cuff repair due to a medium-sized tear. Patients were randomly divided into the FIR or control group (n = 19 per group). In the FIR group, FIR with an FIR radiator started 1 week postoperatively for 30 minutes per session twice daily. It lasted until abduction brace weaning at 5 weeks postoperatively. We assessed pain using a pain visual analogue scale (pVAS) and measured the range of motion (ROM) of the shoulder at 5 weeks, and 3 and 6 months, postoperatively. The anatomical outcome was evaluated using magnetic resonance imaging at 6 months postoperatively. Results: At 5 weeks postoperatively, the average pVAS score was lower in the FIR group than in the control group (1.5 ± 0.8 vs. 2.7 ± 1.7; P = 0.019). At 3 months postoperatively, the average forward flexion was higher in the FIR group (151.6° ± 15.3° vs. 132.9° ± 27.8°; P = 0.045), but there was no significant difference at 6 months postoperatively. There was no significant difference in healing failure between the groups (P = 0.999). Conclusions: FIR after arthroscopic rotator cuff repair could be an effective and safe procedure to reduce postoperative pain, thereby facilitating rehabilitation and better ROM in the early postoperative period.
... In these experimental conditions, FIR-emitting materials would confer anti-inflammatory [3], antioxidant [4] and antimicrobial [5] effects as well as rejuvenating skin and potentially muscle-tendon unit tissue [6]. These effects may delay the appearance of muscle fatigue [7], promote peripheral microcirculation [8] and cerebral blood flow [9] and enhance blood circulation and metabolism [10]. ...
... Possible mechanisms which could explain a performance enhancement include haemodynamic changes, better thermoregulation, or a lower exercise-induced fatigue, as suggested by in vitro and animal studies (e.g. [3,7,8,40]). Leung et al. [7] reported that FIR-irradiated isolated amphibian muscles were more resistant to fatigue during exercise and accumulated less metabolic by-products. ...
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Background Thanks to the specific materials they embed, far infrared (FIR)-emitting garments can interact with the body’s physiological functions. Such effects have been sought in medicine and physiotherapy for a long time for the treatment/relief of a variety of pathologies and disabling conditions. Recently, FIR-emitting garments have been introduced in the sporting domain under the influence of manufacturers seeing here a new opportunity to support physical performance in athletes, though this is not clearly established. To fill this gap, in this systematic review, we summarize the scientific evidence on the use of FIR-emitting garments in sport and provide directions for future research by shedding light on current scientific limitations. Method Five scientific databases (PubMed, Cochrane, ScienceDirect, Scopus and SPORTDiscus) were searched by two independent reviewers. Studies investigating the effects of FIR-emitting garments on at least one physiological outcome related to exercise performance and/or recovery in humans were selected. The methodological quality of retained studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. Results and discussion Eleven studies met the inclusion criteria and were included in the systematic review. Studies investigating similar outcomes related to exercise performance or recovery were scarce and results inconclusive, which prevents from drawing firm conclusion about the utilisation of FIR-emitting garments in athletes. However, these early results show that FIR-emitting garments may be of interest for exercise performance and recovery, mainly through their effects on the body’s thermoregulation and haemodynamic function. The summary provided in this review can be used to inform the design of future studies. (PROSPERO registration number: CRD42021238029).
... Electronics 2020, 9, 138 2 of 14 endothelium [6]. There are three types of techniques for FIR radiation delivery: FIR saunas, FIR heat lamps, and FIR-emitting ceramics and fabrics [1]. ...
... There are three types of techniques for FIR radiation delivery: FIR saunas, FIR heat lamps, and FIR-emitting ceramics and fabrics [1]. In general, FIR heat lamps are used widely in hospitals for different kinds of therapy [1][2][3][4][5][6][7]. In addition, a previous study demonstrated the benefits of combined acupuncture-FIR heat lamps in enhancing peripheral perfusion and parasympathetic activity [7]. ...
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A microcirculation microscope has recently been introduced to reveal finger blood flow changes by visualization, before and after using far-infrared fabric. Digital volume pulses (DVPs) from the dominant index fingertip of healthy young subjects (Group 1, n = 66) and healthy upper middle-aged subjects (Group 2, n = 33) were acquired through a photoplethysmographic electrical device (PED). By using the one intrinsic mode function (i.e. IMF5), an instantaneous frequency difference (ΔfEmax) was revealed through the second part of the Hilbert–Huang transformation. Parameters from DVPs in the time domain, i.e. the stiffness index, crest time, crest time ratio, and finger perfusion index, were also obtained for comparison. The results showed significant differences in FPI and ΔfEmax between the two groups (p = 0.002 and p = 0.043, respectively). A significant ΔfEmax was also noted for the two groups under the effects of far-infrared radiation (FIR) (Group 1: p = 0.046; Group 2: p = 0.002). In conclusion, this study aimed to validate a self-developed and economical device, with a good extensibility, which can be operated in a domestic setting, and to demonstrate that the PED performed quantitative indexes on finger blood flow comparable to those investigated through a microcirculation microscope.
... In recent years, many studies have examined the effects of FIR on human health and cell physiology [1][2][3][4][5][6][7][8] , which suggest that FIR have great potential for application in health care. However, the biological effects of FIR that have been discovered so far are difficult to be quantitatively analyzed. ...
... The biological effects of FIR that have been discovered on mammalian cells are variable [1][2][3][4][5][6][7][8] . Whether the FBI detection method is applicable in all systems is still uncertain. ...
Article
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Far-infrared radiation (FIR) exerts numerous beneficial effects on health and cell physiology. Recent studies revealed that the biological effects of FIR are independent of thermal effects. There is no proper method for measuring the parameters of the non-thermal biological effects of FIR, which limits its biomedical application. In this study, we established a cell detection platform using epithelial cell migration to measure the limits of the biological effects of FIR. FIR promoted the migration of rat renal tubular epithelial cells as revealed by our standardized detection method. We defined the ratio of the FIR-promoted migration area to the migration area of the control group as the FIR biological index (FBI). An increase of the FBI was highly associated with FIR-promoted mitochondrial function. Through FBI detection, we revealed the limits of the biological effects of FIR, including effective irradiation time, wavelengths, and temperature. FBI detection can be used to clarify important parameters of the biological effects of FIR in biomedical studies and health industry applications.
... Results from previous clinical studies suggest that FIR therapy can be used to increase cardiopulmonary exercise tolerance [1,2], improve patency and flow in arteriovenous fistulas in patients with hemodialysis [3] and reduce the probability of re-occlusion within one year after percutaneous transluminal angioplasties [4]. Animal studies have also shown that FIR therapy can increase the expression of heme oxygenase-1 in testes after ischemic injury [5], increase the biological effects of skin microcirculation [6], promote sciatic nerve repair in neuropathy [7], promote ischemia-induced angiogenesis, and restore high glucose-suppressed endothelial progenitor cell (EPC) functions [8]. Previous findings have shown the effectiveness of FIR therapy in the treatment of systemic diseases, including cardiovascular diseases, diabetes mellitus, tissue ischemia, malfunction of native arteriovenous fistulas and prosthetic arteriovenous grafts, chronic pain, and chronic fatigue syndrome [9]. ...
... There are many ways to implement FIR therapy in clinical practice [6,36,37], and they always provide thermal and non-thermal effects to increase blood flow [38,39], maintain endothelial function, lower blood pressure [40,41], and regulate nerve function [42,43]. Compared to the other diseases, FIR therapy, has a significant impact on cardiovascular diseases. ...
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Orthotopic allograft transplantation (OAT) is a major strategy for solid heart and kidney failure. However, the recipient’s immunity-induced chronic rejection induces OAT vasculopathy that results in donor organ failure. With the exception of immunosuppressive agents, there are currently no specific means to inhibit the occurrence of OAT vasculopathy. On the other hand, far-infrared (FIR) therapy uses low-power electromagnetic waves given by FIR, with a wavelength of 3–25 μm, to improve human physiological functions. Previous studies have shown that FIR therapy can effectively inhibit inflammation. It has also been widely used in adjuvant therapy for various clinical diseases, especially cardiovascular diseases, in recent years. Thus, we used this study to explore the feasibility of FIR in preventing OAT vasculopathy. In this study, the model of transplantation of an aorta graft from PVG/Seac rat to ACI/NKyo rat, and in vitro model of human endothelial progenitor cells (EPCs) was used. In this report, we presented that FIR therapy decreased the serious of vasculopathy in OAT-recipient ACI/NKyo rats via inhibiting proliferation of smooth muscle cells, accumulation of collagen, and infiltration of fibroblast in the vessel wall; humoral and cell-mediated immune responses were decreased in the spleen. The production of inflammatory proteins/cytokines also decreased in the plasma. Additionally, FIR therapy presented higher mobilization and circulating EPC levels associated with vessel repair in OAT-recipient ACI/NKyo rats. In vitro studies demonstrated that the underlying mechanisms of FIR therapy inhibiting OAT vasculopathy may be associated with the inhibition of the Smad2-Slug axis endothelial mesenchymal transition (EndoMT). Thus, FIR therapy may be the strategy to prevent chronic rejection-induced vasculopathy.
... The underpinning mechanisms of FIR therapy effects are not clear yet, but previous studies suggest that FIR produce both nonthermal and thermal effects including an increase in microvascular dilation, increased blood flow, and elevated regional tissue temperature, albeit in rats. 16,17 Thus, it is interesting to investigate the effects of FIR lamp therapy on muscle damage accumulated in multiple simulated soccer matches. ...
... It has been documented that FIR produces both nonthermal and thermal effects, including an increase in microvascular dilation, increased blood flow volume, and elevated regional tissue temperature, based on animal studies. 16,17 It seems possible that the FIR lamp treatment effects were due to a combination of increased microvascular blood flow, 17,24 anti-inflammatory effect via the induction of the heme oxygenase-1, 25 increased transforming growth factor-β1 that could increase cellular growth and proliferation, and increased expression myofibroblasts and collagen content on a skin wound area using a rat model, 26 increased nitric oxide, intracellular heat shock proteins, antioxidant effects, and pain relief effects with prostaglandin E 2 production. 15 Future studies are required to examine the mechanisms. ...
Article
Purpose: The authors investigated whether far-infrared radiation (FIR) lamp therapy would reduce muscle damage and enhance recovery from multiple soccer-match-related running activities. Methods: Twenty-four elite female soccer players (20-24 y) were assigned into a FIR or a sham treatment group (n = 12/group). They performed a daily 90-minute Loughborough Intermittent Shuttle Test (LIST) for 6 consecutive days. Maximal voluntary contraction torque of the knee extensors (KEs) and flexors, muscle soreness, plasma creatine kinase activity, countermovement jump, and several other performance measures (eg, 30-m dash, Yo-Yo Intermittent Recovery Test Level 1) were taken before the first LIST, 1 hour after each LIST, and 24, 48, 72, 96, and 120 hours after the last LIST. All participants received a 30-minute FIR or sham treatment on KEs and knee flexors, respectively, at 2 hour after each LIST and 25, 49, 73, and 97 hours after the last LIST. Results: All measures changed significantly (P < .05) at 1 hour after the first LIST without difference (P > .05) between groups. Maximal voluntary contraction torque (eg, the largest decrease of KE for FIR: 13% [4%], sham: 25% [5%]), countermovement jump height (4% [3%] vs 14% [4%]), and other performance measures (eg, Yo-Yo Intermittent Recovery Test: 11% [5%] vs 26% [5%]) decreased less, and peak muscle soreness (eg, KE: 26 [9] vs 51 [18] mm) and plasma creatine kinase activity (172 [32] vs 1289 [610] IU/L) were smaller for the FIR than for the sham group (P < .05), and they returned to the baseline earlier (P < .05) for the FIR group. Conclusions: These results suggest that the FIR therapy provided potent effects on reducing accumulated muscle damage and enhancing recovery.
... In this way, skin blood microcirculation is promoted and a thermal response is produced. Moreover, far-infrared fabric can also reflect heat radiation back to the body and facilitate health care functions, such as activating the body, eliminating fatigue, improving immunity, etc. [33,34]. The microPCM function layer can be used as a heat source to release a certain amount of heat in a low-temperature environment. ...
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Based on active heating materials (the phase change microcapsules (microPCMs)) and passive insulating materials (SiO2 aerogel), a new-type multilayer low temperature protective composite fabric (MPF) was designed and manufactured to meet the demands of protection and operation in a short time under a low-temperature environment. Results showed that the MPF consisted of three layers including the fabric layer, the microPCM function layer, and the SiO2 aerogel thermal insulation layer. The differential scanning calorimeter (DSC) results demonstrated that the phase transition enthalpy of the composite was 96.2 J/g during the cooling process. The low-temperature resistance and thermal insulation performance at −50 °C were investigated. The results also demonstrated that the low-temperature resistance time of the MPF was 660 s and the power consumption of the MPFs needed to maintain 37 °C for 10 and 20 min were 629 J and 1872 J, respectively. Compared with the microPCM function layer and the thermal insulation layer, which have the same thickness as the MPF, the low-temperature resistance time of the MPF was prolonged for about 2 and 3 min, respectively. The MPF could provide effective protection of the low-temperature work in a short time and could be applied as potential materials in low-temperature protection.
... Indeed, FIRT has been used for the treatment of ischemic lesions or skin necrosis due to injury, diabetes, or peripheral nerve disease. Such studies have suggested that FIRT may improve vascular endothelial function and decrease endothelial dysfunction in patients with coronary artery disease, heart failure, and arrhythmia [3,4]. One previous study in Taiwan examined the effects of FIRT in HD patients and showed that it steadily increased arteriovenous fistula (AVF) blood flow. ...
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Far-infrared radiation therapy (FIRT), which utilizes an invisible electromagnetic wave, has demonstrated its ability to improve vascular access flow for hemodialysis (HD) patients. Although previous overseas studies revealed the beneficial effects of FIRT on HD patients by improving vascular function, no study in Japan has examined the clinical efficacy of FIRT for such patients. Therefore, we aimed to evaluate the usefulness of FIRT for HD patients. We paid particular attention on secondary vascular access (VA) patency of HD patients. Eighteen patients who had undergone vasodilation of VA vessels or vascularization more than once were selected from approximately 70 outpatients receiving HD in the Dialysis Unit of the Juntendo University Hospital. FIRT was administered for 40 min during HD three times per week for 1 year to the not frequent VA treatment (nf-VAT) group, for which VA intervention had been performed no more than two times during the 1 year, and to the frequent VA treatment (f-VAT) group, for which VA intervention had been performed three times or more over the 1 year. Variables including VA treatment interval were compared between those groups. The nf-VAT group did not require VA re-treatment during the study period. The VA treatment interval was significantly prolonged in the f-VAT group. The fistula diameter expanded, and intimal thickening improved significantly in the nf-VAT group. Oxidized low-density lipoprotein cholesterol levels decreased slightly. This study suggested that FIRT is effective for improving secondary VA patency. UMIN, UMIN000011965. Registered 4 October 2013, Japanese: https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R000013960, English: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000013960
... When soft tissue is heated by infrared radiation, heat will be generated by resonance and friction between molecules because the vibration frequency of partial far infrared rays is close to that of intracellular molecules in soft tissue, which causes an increase in skin temperature and accelerates blood circulation [8,35]. The thermal effect in the heated side of limbs will be regulated by the thermoregulation of central nervous systems, making the temperatures in the contralateral side and the irradiated side close [36]. ...
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Backgroud: The lower extremities of the body often suffer from impaired microcirculation, particularly in the elderly or people with underlying conditions such as diabetes. Especially for people suffering from peripheral vascular diseases, skin lesions or wearing an external fixator in one side of limbs, direct contact treatments are not suitable for them to improve microcirculation. Heating the contralateral limb has been reported to improve blood flow in the impaired limb. However, its effect on plantar microvascular responses has not been previously investigated. Thus, the aim of this study was to explore how heating by warm bath and infrared radiation affects the circulations in the contralateral foot. Twelve healthy adults participated in this study and were randomly assigned to either placing the left foot in a warm bath or exposing it to infrared radiation for 10 minutes intervention every other day. The skin temperature (Temp) and skin blood flow (SBF) in the second metatarsal head of the contralateral foot were measured before and after the intervention. Results: The results showed that both Temp (Bath: from 29.05±3.56 °С to 31.03±4.14 °С; Infrared: from 29.98±3.86 °С to 31.07±3.92 °С) and SBF (Bath: from 62.26±48.12 PU to 97.76±63.90 PU; Infrared: from 63.37±39.88 PU to 85.27±47.62 PU) in the contralateral foot were significantly increased after heating in both tests (P<0.05). However, the contralateral SBF increased for 5 minutes after heating in warm bath test, but only for 1 minute in infrared radiation test. Conclusions: The results of this study show that both heating methods are the effective at increasing contralateral Temp and SBF, but the warm bath has a stronger residual thermal effect.
... The new treatment cabin. Open Journal of Regenerative Medicine microcirculation and basal metabolism[9], enhance immunity [10][11]. ...
... Concerning FIR therapy, previous studies have shown that it could increase temperature in the body tissues, elevate motility of body fluids (27), and exert a nitric oxide (NO)related biological effect to increase skin microcirculation in rats (27,28). In addition, FIR may reduce the growth of some cancer cells in vitro with a low level of heat shock protein 70 (29). ...
Article
Background/aim: Malignant glioma is a rapidly progressive primary brain cancer. The aim of the study was to investigate the effect of far-infrared ray (FIR) on temozolomide (TMZ)-treated glioma in rats. Materials and methods: Male, 8-week old, Fischer 344 inbred rats with glioma were randomly divided into three study groups (20 rats in each group). The control group received saline only once daily for 5 days. The TMZ group received TMZ (30 mg/kg) once daily for 5 days. The TMZ plus FIR group received TMZ (30 mg/kg) once daily for 5 days and infrared-c irradiation of 40 min twice daily for 4 weeks. The relative tumor fold and the expression of hypoxia-induced factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) were compared using one-way ANOVA at the end of study. Results: The relative tumor fold of the TMZ+FIR group was significantly higher compared to the control group, and was borderline higher compared to the TMZ group at Day 7. The relative tumor fold of TMZ+FIR group was significantly higher compared to the control group and the TMZ group at Days 14, 21 and 28. HIF-1α expression of TMZ+FIR group was borderline higher compared to the control group at Day 28. The VEGF expression of TMZ+FIR group was significantly higher compared to the control group and the TMZ group at Day 28. Conclusion: FIR might increase the growth of glioma under TMZ treatment in rats possibly via increasing VEGF expression, but not HIF-1α expression.
... In particular, some evidence suggests FIR exposure can positively impact several indices of cardiovascular health. Animal models have reported beneficial effects of FIR exposure on blood pressure (Lin et al., 2016), depressive symptoms (Tsai et al., 2007), endothelial function (Chen et al., 2017), microcirculation (Yu et al., 2006), new blood vessel formation , restraint stress-related changes (Tran et al., 2016) and wound healing (Toyokawa et al., 2003). A few preliminary human studies on FIR have reported increased flow mediated dilation, thereby improving impaired vascular endothelial function in patients with at least one risk factor of coronary atherosclerosis (Imamura et al., 2001). ...
Article
Both sun exposure and serum vitamin D levels have been associated with lower risks of all-cause mortality and chronic age-related diseases, e.g., cancer, diabetes and cardiovascular disease, in epidemiological studies. These associations have mainly been ascribed to beneficial effects of vitamin D. However, a vast body of randomized controlled trials (RCTs) and Mendelian randomization studies have failed to confirm any major health benefits from vitamin D supplementation. In this review, we present tentative evidence showing that red and near-infrared light, both being present in sunlight, could explain the associations between sunlight exposure and better health status. Body irradiation with red and near-infrared light, usually termed as photobiomodulation (PBM), has demonstrated beneficial effects in animal models of chronic diseases. Beyond this, preliminary evidence from RCTs suggest potential clinical benefit from PBM for chronic diseases. PBM is currently being investigated in many pre-registered clinical trials, results of which will eventually clarify the role of red and near-infrared light in the prevention and treatment of common age-related chronic diseases.
... In addition, increased cell proliferation was noted for a number of days after far infrared treatment, but this effect was lost with time. Far infrared therapy has a distinct advantage as a modification technique as it is already commercially used to improve chronic wound healing and peripheral circulation [49], but more research is needed to examine the effect of far infrared treatment on ECFCs and the angiogenic potential of these modified cells in vivo before progressing to a clinical trial. ...
Article
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Endothelial-colony-forming cells (ECFCs) are a population of progenitor cells which have demonstrated promising angiogenic potential both in vitro and in vivo. However, ECFCs from diabetic patients have been shown to be dysfunctional compared to ECFCs from healthy donors. Diabetes mellitus itself presents with many vascular co-morbidities and it has been hypothesized that ECFCs may be a potential cell therapy option to promote revascularisation in these disorders. While an allogeneic cell therapy approach would offer the potential of an ‘off the shelf’ therapeutic product, to date little research has been carried out on umbilical cord-ECFCs in diabetic models. Alternatively, autologous cell therapy using peripheral blood-ECFCs allows the development of a personalised therapeutic approach to medicine; however, autologous diabetic ECFCs are dysfunctional and need to be repaired so they can effectively treat diabetic co-morbidities. Many different groups have modified autologous diabetic ECFCs to improve their function using a variety of methods including pre-treatment with different factors or with genetic modification. While the in vitro and in vivo data from the literature is promising, no ECFC therapy has proceeded to clinical trials to date, indicating that more research is needed for a potential ECFC therapy in the future to treat diabetic complications.
... In the Infectiology field, we have only one report of a series of cases of patients with Sporotrichosis treated successfully with FIR [5]. Also, there are reports of experimental studies like: FIR healed the wounds significantly more quick in rats skin, increasing the regeneration of collagen and the infiltration of fibroblasts which express the growing factor TGF-BETA1 [8], the FIR has a biological effect related to nitric oxide for increasing the microcirculation of the skin in rats, which could have clinical utility for the treatment of ischemic diseases [9], the treatment with FIR during next 48 hours after produced decrease of 11.8% in the proliferation of melanoma merino cells [10]. A systemic revision, has raised that the mechanism of action of FIR could be closely connected with the increased Nitric oxide sintetasa endothelial as well as in the Nitric Oxide production and could be responsible of the modulate of the profiles of some miARNS in circulation [4], on the other hand, we know that in the pathogenesis of the tuberculosis, the molecule of Nitric Oxide is a key and effective against the ...
... (Li, Suo, & Deng, 2010;Mallakpour & Dinari, 2013). ZrO 2 is one type of potential inorganic nanoparticle with a high refractive index, high heat resistance, and the possibility of enhancing human immunologic function as a farinfrared material (Haldorai, Zong, & Shim, 2012;Yu, Chiu, Yang, Hsu, & Wu, 2006). In terms of antibacterial properties, nisin is one of a widely used toxicologically safe, natural additive for food antibacterial preservation. ...
Article
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The properties of manufactured nisin-ZrO2/poly (vinyl alcohol)-wheat gluten (ZPWG) films were characterized. The formation of hydrogen bonds among the PVA, WG, and ZrO2 units were detected and caused a decrease in the film crystallinity. Also, the degradation rate was increased with WG content. As expected, the addition of WG and ZrO2 influenced the light transmission, tensile properties, gas permeability and water vapor permeability of the films. Nisin-loaded films presented a low initial burst release of the antimicrobial agent, followed by a gradual release. The initial diffusion of nisin (Mt/M∞<2/3) from the ZPWG film was formulated by the Fickian diffusion equation, showing a linear relationship (R² > 0.998) between Mt/M∞ and t1/2, and the diffusion coefficient D increased with increasing WG content. Antimicrobial activity testing of nisin-ZPWG films with 40 wt% WG showed excellent inhibitory activity against Staphylococcus aureus, indicating its potential as a new active food packaging material.
... Using the same principle, infrared ray seemed to have potential as a therapeutic intervention for MPS. Among three types of infrared radiation (near-infrared radiation, middle-infrared radiation, and far-infrared radiation (FIR)), FIR has demonstrated its effect in increasing microcirculation of the skin possibly via stimulating nitric oxide production [96,97]. As local ischemia seems to play a role in pain sensitization of MPS, improvement in microcirculation using FIR was thought to be a plausible way to ameliorate the symptoms of MPS. ...
Myofascial Pain Syndrome (MPS) is a regional pain disorder that affects every age group and is characterized by the presence of trigger points (TrPs) within muscles or fascia. MPS is typically diagnosed via physical exam, and the general agreement for diagnostic criteria includes the presence of TrPs, pain upon palpation, a referred pain pattern, and a local twitch response. The prevalence of MPS among patients presenting to medical clinics due to pain ranges anywhere from 30-93%. This may be due to the lack of clear criteria and guidelines in diagnosing MPS. Despite the prevalence of MPS, the pathophysiology of it remains incompletely understood. There are many different ways to manage and treat MPS. Some include exercise, TrP injections, medications, and other alternative therapies. There needs to be more research done to form uniformly accepted diagnostic criteria and treatments.
... When soft tissue is heated by infrared radiation, heat will be generated by resonance and friction between molecules because the vibration frequency of partial far infrared rays is close to that of intracellular molecules in soft tissue, which causes an increase in temperature and accelerates blood circulation [22,23]. The thermal effect in the heated side of limbs will be regulated by the thermoregulation of central nervous systems, making the temperatures in the contralateral side and the irradiated side close [24]. ...
Preprint
Full-text available
Backgroud: The lower extremities of the body often suffer from impaired microcirculation, particularly in the elderly or people with underlying conditions such as diabetes. Especially for people suffering from peripheral vascular diseases, skin lesions or wearing an external fixator in one side of limbs, direct contact treatments are not suitable for them to improve microcirculation. Heating the contralateral limb has been reported to improve blood flow in the impaired limb. However, its effect on microvascular responses has not been previously investigated. Thus, the aim of this study was to explore how heating by warm bath and infrared radiation affects the circulations in the contralateral foot. Twelve healthy adults participated in this study and were randomly assigned to either placing the left foot in a warm bath or exposing it to infrared radiation every other day. The temperature (Temp) and skin blood flow (SBF) in the second metatarsal head of the contralateral foot were measured before and after the intervention. Results: The results showed that both Temp (Bath: from 29.05±3.56 °С to 31.03±4.14 °С; Infrared: from 29.98±3.86 °С to 31.07±3.92 °С) and SBF (Bath: from 62.26±48.12 PU to 97.76±63.90 PU; Infrared: from 63.37±39.88 PU to 85.27±47.62 PU) in the contralateral foot were significantly increased after heating in both tests (P<0.05). However, the increase in contralateral SBF lasted 5 minutes after heating in a warm bath, but only lasted for 1 minute after infrared exposure. Moreover, the increase in Temp from the baseline in the first minute of the Recovery stage was significantly greater when using the warm bath than infrared radiation. Conclusions: The results of this study show that both heating methods are the effective at increasing contralateral Temp and SBF, but the warm bath has a stronger residual thermal effect.
... Animal studies have shown that FIR exposure improves the blood flow to the skin. [12][13][14] This study prospectively analyzed the role of FIR therapy in the maturation of AVF and its role in the maintenance of its patency. ...
Article
Introduction: The goal of arterio-venous fistula (AVF) creation is to achieve a well-functioning access that can be cannulated repetitively and can provide adequate flow for the dialysis. The objective of this study was to assess the role of far infrared (FIR) therapy in the unassisted maturation of newly created AVF in patients with chronic kidney disease (CKD). Materials and methods: In this prospective open labeled randomised control trial, 107 patients were randomized. Participants in the control arm received oral clopidogrel 75 mg once daily for 30 days along with isometric hand exercise, whereas those in the test arm received FIR therapy twice weekly, 40 min session each, for 4 weeks. A biopsy from venous end was taken during fistula surgery. Doppler study of AVF was done at the end of the 4th and 12th week to assess AVF. Vascular access guidelines proposed by National Kidney Foundation -Kidney Disease Outcomes Quality Initiative (NKF- KDOQI) in 2006 were adapted to define the maturation of AVF. Results: Out of 107 patients, 51 were randomized to the test arm and 56 to the control arm. During follow-up, the blood flow rate through AVF (Qa) and the diameter of the cephalic vein draining (CVd) the AVF were measured. At the end of 3 months, Qa in Radio-Cephalic Fistula (RCF) was high in the test arm (p-0.003). The AVF failures were 5 (10.2%) and 14 (28%) in the test and control arms, respectively (p: 0.025). However, when adjusted for AVF failure within 6 h of surgery (may be related to surgical technique) this difference in AVF patency was statistically insignificant (p: 0.121). The mean Qa was high in patients with an arterial intimal medial thickness (AIMT) <0.5 mm. The IMT of the anastomosed artery had statistically significant correlation with the primary failure rate of AVF (P < 0.001). Conclusion: In patients with CKD, FIR therapy was effective in increasing the AVF blood flow rate at the end of 3 months, though the difference in primary failure rate was statistically insignificant.
... The prolonged erythemal response due to FIR exposure has been proposed to be due to increased epidermal temperatures associated with it, but levels of FIR that do not produce any detectable skin heating can also have biological effects. When FIR in the 4-25 micron range is used to focus on a particular point on the skin, they are shown to increase blood flow through increased vasodilation [16]. All of this occurs because this particular wavelength range causes cellular resonance with a byproduct of heat. ...
Article
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The best way to deliver a drug in pursuit of maximum potential is to deliver it with maximal bioavailability. There are many options in delivering a drug, but each way reduces the drug's bioavailability differently. For treating localized discomfort, the transdermal approach or the topical approach is considered to be an advantageous one mainly because of its rapid localized action and the fewest side effects associated with this route. Drug delivery through topicals is an easy-to-reach approach and, in most cases, bypasses the first-pass metabolism. However,under certain conditions, the drug either needs to be delivered in its unaffected, concentrated form or needs to be delivered deeper into the dermal layers of the skin with immediate effect. This paper will review and suggest all those possible ways through which topical drug delivery can be universally enhanced in rate, effectiveness, and efficiency. Specialized ultrasound waves and sub-spectrum far-infrared heat help accelerate and deliver topical ingredients to the site of action. Making this the basis of our argument, we shall see in detail why they help achieve the desired results and why both these methods should be adapted in a combined approach to deliver the drug to the precise site of action through the topical or transdermal approach. Furthermore, Cannabidiol (CBD) is a model drug in this paper due to its faster absorption rate and outnumbered measurable benefits.
... 27 To differentiate the non-thermal FIR effect from thermal FIR effect, Yu and his colleagues found that the skin blood flow did not increase during FIR treatment but increased significantly soon after the removal of the FIR emitter. 28 To evaluate the contribution of non-thermal FIR effect to the increase of blood flow in this study, we estimated the power of the FIR emitted by the blankets by Planck's law of black body radiation: ...
Article
Vascular complications are responsible for most of the morbidity and mortality in diabetic patients. Effective strategies to improve circulation appear to be another important issue in addition to the interventions of blood glucose control. Previous studies have shown that the biological effects on humans after using the materials containing ceramic particles emits far infrared radiation (FIR). The present study is to investigate the warming effect of the fabrics containing specified metals in diabetic patients. A total of 28 diabetic patients were blinded and randomly assigned to treatment group ([Formula: see text]) and control group ([Formula: see text]), respectively. The subjects of treatment group were ministered with the blankets with fibers containing the specified metals, while the subjects of control group were provided with blankets of ordinary material. The skin temperature and microcirculatory perfusion were monitored before and after 20-min use of the blankets at shoulder and bilateral calves. After warming with blankets, the treatment group revealed a higher increased ratio of skin perfusion than control ([Formula: see text]), while there was no prominent variation on the wavelet spectrum of the perfusion signal. Although it is already a known fact that passive FIR warming has the advantages of safety and convenience, our results suggest that warming by wearing the textiles containing the specified metals with high FIR emissivity is a solution for daily skin care of diabetic patients.
... FIR effectively penetrates the subcutaneous tissues and reduces discomfort (8). It has been particularly maintained that thermotherapy using FIR can increase the blood flow and cell metabolism (12), reduce pain, lead to body tissue regeneration, increase oxygen delivery, and activate the immune response (13). The process of controlling and reducing uremic pruritus in hemodialysis patients, has recently become focused on thermotherapy, and the research evidence has shown that thermotherapy using FIR significantly improves dialysis adequacy (14), therefore it can have positive effects on the QOL of patients under hemodialysis. ...
Article
Introduction and objective: Uremic pruritus is a common symptom in patients under hemodialysis. The exact cause of uremic pruritus is not yet known. Although effective treatments are available, there is not still a commonly accepted treatment for this disorder. The present study was aimed at examining the effects of thermotherapy on the quality of life (QOL) and biochemical parameters in hemodialysis patients with uremic pruritus. Patients and methods: In this experimental study, a total of 40 men under hemodialysis suffering from uremic pruritus were randomly selected and divided into an experimental group (thermotherapy) and a control group (no exposure to heat). The experimental group were exposed to far-infrared radiation (FIR) at 40 °C in 15-minute sessions, three times a week, in total for 18 sessions. The Severity of Pruritus Scale (SPS), the Kidney Disease Quality of Life Instrument (KDQOL), and the ItchyQoL were completed by the participants before the start of intervention, one month after the start of intervention, and at the end of intervention. The data were analyzed using SPSS22. Results: Significant differences were observed between the intervention and control groups in all the criteria for assessing uremic pruritus, including history of symptoms, daily activities, QOL, effects on sleep, emotional aspects, and severity of pruritus (p<0.001). In addition, significant improvements were found after the intervention in the criteria for assessing the QOL of the patients (p<0.001). Moreover, improvements in the calcium and phosphorus levels were observed in the intervention group in comparison with the control group. Conclusion: Thermotherapy is effective in reducing the severity of pruritus and increasing the QOL of patents with this problem. Therefore, it can be used as a complementary method in treating patients with uremic pruritus who also experience a reduction in their QOL. Keywords: Hemodialysis, Thermotherapy, Uremic pruritus, Quality of life, Biochemical parameters
... Studies have shown that red light can stimulate cells, especially fibroblasts, to repair tissue. It is widely used in the treatment of skin diseases, common skin ulcers, sores, and herpes zoster [29]. When the red light is applied to the repair of striae gravidarum, the epidermis will selectively absorb red light and stimulate the damaged collagen cortex to constantly repair itself, to improve the skin condition. ...
Article
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Background Striae gravidarum is a common occurrence in pregnancy and many women expect to prevent its development. At present, laser treatment has been used to improve the appearance of striae gravidarum, but the choice of laser type, treatment time, and frequency depend on the therapeutic effect. How to obtain an effective evaluation of striae gravidarum during and after treatment is very important. However, there is no unified evaluation parameter about striae gravidarum. In this paper, we studied the methodology evaluation of striae gravidarum severity. First, the laser therapeutic apparatus was selected as the experimental equipment and different striae gravidarum photos during treatment were obtained. Second, the subject evaluation parameters were chosen based on the literature research and the dermatologists’ guidance. Then, the striae gravidarum photos were divided into different groups by dermatologists based on these parameters. Finally, the objective detection parameters were designed based on the photos feature and subject evaluation parameters. Then, the objective detection parameters were used as the input of the support vector machine and the evaluation results were compared. Results Based on the subject evaluation parameters, the experimental data could be divided into mild, moderate and severe groups. The experiment results showed that the striae gravidarum severity of two randomly patients were improved before and after treatment, which verified the validity of the parameters. In addition, the chosen objective detection parameters were different among different groups. With all the objective parameters as the support vector machine input, we could achieve the best recognition rate (82.71%) in the striae gravidarum severity classification. The four parameters (color difference, average density, average width, distribution area) calculated from the photos as the input could achieve acceptable accuracy (81.69%). Conclusions The subject evaluation parameters and objective detection parameters proposed in this paper can be used to evaluate the striae gravidarum severity, which is of great significance for the construction of auxiliary diagnostic instrument for striae gravidarum treatment.
... When soft tissue is heated by infrared radiation, heat will be generated by resonance and friction between molecules because the vibration frequency of partial far infrared rays is close to that of intracellular molecules in soft tissue, which causes an increase in skin temperature and accelerates blood circulation [8,35]. The thermal effect in the heated side of limbs will be regulated by the thermoregulation of central nervous systems, making the temperatures in the contralateral side and the irradiated side close [36]. ...
Article
Full-text available
Background The lower extremities of the body often suffer from impaired microcirculation, particularly in the elderly or people with underlying conditions such as diabetes. Especially for people suffering from peripheral vascular diseases, skin lesions or wearing an external fixator in one side of limbs, direct contact treatments are not suitable for them to improve microcirculation. Heating the contralateral limb has been reported to improve blood flow in the impaired limb. However, its effect on plantar microvascular responses has not been previously investigated. Thus, the aim of this study was to explore how heating by warm bath and infrared radiation affects the circulations in the contralateral foot. Twelve healthy adults participated in this study and were randomly assigned to either placing the left foot in a warm bath or exposing it to infrared radiation for 10 min intervention every other day. The skin temperature (Temp) and skin blood flow (SBF) in the second metatarsal head of the contralateral foot were measured before and after the intervention. Results The results showed that both Temp (Bath: from 29.05 ± 3.56 °C to 31.03 ± 4.14 °C; Infrared: from 29.98 ± 3.86 °C to 31.07 ± 3.92 °C) and SBF (Bath: from 62.26 ± 48.12 PU to 97.76 ± 63.90 PU; Infrared: from 63.37 ± 39.88 PU to 85.27 ± 47.62 PU) in the contralateral foot were significantly increased after heating in both tests ( p < 0.05). However, the contralateral SBF increased for 5 min after heating in warm bath test, but only for 1 min in infrared radiation test. Conclusions The results of this study show that both heating methods are the effective at increasing contralateral Temp and SBF, but the warm bath has a stronger residual thermal effect.
... Eventually, the anti-inflammatory effect of FIR was also demonstrated in patients receiving hemodialysis [31]. In previous animal model literature, FIR was able to increase skin blood flow in rats [32], increase the expression of arterial endothelial nitric oxide synthase and nitric oxide synthesis in hamsters [33], promote angiogenesis in mice with non-thermal effect [34], and inhibit interleukin-6 and TNF-α activity in mice with peritonitis [35]. FIR has been applied to many clinical therapeutic applications where it can improve nasal stuffiness of allergic rhinitis [36], ameliorate access flow and patency of arteriovenous fistula on hemodialysis patients [37,38], and relieve discomforts of primary dysmenorrhea [39]. ...
Article
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Peritoneal dialysis (PD) is a treatment modality for end-stage renal disease (ESRD) patients. Dextrose is a common osmotic agent used in PD solutions and its absorption may exacerbate diabetes mellitus, a common complication of ESRD. PD solutions also contain glucose degradation products (GDPs) that may lead to encapsulating peritoneal sclerosis (EPS), a severe complication of PD. A previous study showed that far-infrared (FIR) therapy improved a patient’s gastrointestinal symptoms due to EPS. Due to limited literature on the matter, this study aims to investigate dialysate GDPs and peritoneal function in diabetic patients on PD. Thirty-one PD patients were enrolled and underwent 40 min of FIR therapy twice daily for six months. We demonstrated the effect of FIR therapy on the following: (1) decrease of methylglyoxal (p = 0.02), furfural (p = 0.005), and 5-hydroxymethylfurfural (p = 0.03), (2) increase of D/D0 glucose ratio (p = 0.03), and (3) decrease of potassium levels (p = 0.008) in both DM and non-DM patients, as well as (4) maintenance and increase of peritoneal Kt/V in DM and non-DM patients, respectively (p = 0.03). FIR therapy is a non-invasive intervention that can decrease dialysate GDPs in PD patients by improving peritoneal transport rate and solute removal clearance, while also maintaining dialysis adequacy.
... Even if FIR emission by minerals placed in proximity of the skin can be considered as low compared to FIR heating devices, various observations indicate that it may result in physiological reactions similar to that induced in medical infrared heating settings. Specifically, NO-mediated vasodilation has been suggested as a possible mechanism of positive FIR influence on wound healing [165]. So far, experimental results converge rather towards a possible antioxidant mechanism of action and require further research [166]. ...
Article
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As odd as it may seem at first glance, minerals, it is what we are all about…or nearly. Although life on Earth is carbon-based, several other elements present in the planet’s crust are involved in and often indispensable for functioning of living organisms. Many ions are essential, and others show supportive and accessory qualities. They are operative in the skin, supporting specific processes related to the particular situation of this organ at the interface with the environment. Skin bioenergetics, redox balance, epidermal barrier function, and dermal remodeling are amongst crucial activities guided by or taking advantage of mineral elements. Skin regenerative processes and skin ageing can be positively impacted by adequate accessibility, distribution, and balance of inorganic ions.
... Our result may also rely on the method used to promote warming. One study in animal models suggests that infrared radiation leads to a non-thermic effect causing local vasodilatation, which may be attributed to the mobilization of biochemical markers [27]. This hypothesis still needs further investigation but may support our results that warming the instep also led to a plantar improvement. ...
Article
Despite controversial evidence, foot sensitivity may influence postural control. Since skin temperature changes may induce changes in skin sensitivity, it remains unclear whether this also affects postural control. Here we examined the effects of increasing foot temperature on foot sensitivity and postural control responses. We hypothesized that increases in foot temperature would improve foot sensitivity and enhance postural control. Furthermore, we investigated whether warming a larger foot area provides additional benefits. We tested our hypothesis by warming the foot plantar and the whole foot and ankle area (including foot plantar and instep) using infrared radiation and evaluated the center of pressure (CoP, bilateral, in two conditions: eyes open and eyes closed) and foot tactile sensitivity (Semmes-Weinstein Monofilaments) in 22 young participants. Both warming protocols significantly increased foot temperature by ∼5-6 °C and improved sensitivity, whereas more considerable improvements happened after warming the whole foot and ankle. CoP mediolateral oscillation and velocity with eyes open, and CoP area and velocity with eyes closed reduced after both warming protocols. Foot sensitivity seems to depend on the foot area warmed, whereas postural control improved equally regardless of the warmed regions. These results may support interventions based on the manipulation of foot temperatures to improve postural control with potential clinical applications in populations with impaired foot sensitivity and balance.
... Far-infrared (FIR) therapy utilizes FIR radiation with a wavelength range of 5.6-1000 μm that is perceived as heat by receptors in the skin [7]. The skin surface temperature can steadily progress to approximately 38-39 °C during FIR therapy for 30-60 min [8]. When compared with conventional thermal therapy methods, FIR therapy has considerably less risk of side effects such as burn injury, infection, risk of vascular access failure, or prolonged bleeding from the previous venipuncture site. ...
Article
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Long-term peritoneal dialysis (PD) can lead to detrimental changes in peritoneal membrane function, which may be related to the accumulation of glucose degradation products. A previous study demonstrated that 6 months of far-infrared (FIR) therapy may decrease glucose degradation products in PD dialysate. Due to limited literature on this matter, this study aims to investigate the effect of FIR therapy on the peritoneal membrane transport characteristics of PD patients. Patients were grouped according to baseline peritoneal transport status: lower transporters (low and low-average) and higher transporters (high-average and high). Both groups underwent 40 min of FIR therapy twice daily for 1 year. In lower transporters, FIR therapy increased weekly dialysate creatinine clearance (6.91 L/wk/1.73 m2; p = 0.04) and D/P creatinine (0.05; p = 0.01). In higher transporters, FIR therapy decreased D/P creatinine (−0.05; p = 0.01) and increased D/D0 glucose (0.05; p = 0.006). Fifty percent of high transporter patients shifted to high-average status after FIR therapy. FIR therapy may decrease D/P creatinine for patients in the higher transporter group and cause high transporters to shift to high-average status, which suggests the potential of FIR therapy in improving peritoneal membrane function in PD patients.
... The FIR band comprises the longest wavelengths (λ = 3 -100 μm) of the infrared radiation band. In the past various studies provided evidence that far-infrared irradiation produces both non-thermal and thermal effects [2,3]. ...
... When soft tissue is heated by infrared radiation, heat will be generated by resonance and friction between molecules because the vibration frequency of partial far infrared rays is close to that of intracellular molecules in soft tissue, which causes an increase in skin temperature and accelerates blood circulation [8,35]. The thermal effect in the heated side of limbs will be regulated by the thermoregulation of central nervous systems, making the temperatures in the contralateral side and the irradiated side close [36]. ...
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Backgroud: The lower extremities of the body often suffer from impaired microcirculation, particularly in the elderly or people with underlying conditions such as diabetes. Especially for people suffering from peripheral vascular diseases, skin lesions or wearing an external fixator in one side of limbs, direct contact treatments are not suitable for them to improve microcirculation. Heating the contralateral limb has been reported to improve blood flow in the impaired limb. However, its effect on plantar microvascular responses has not been previously investigated. Thus, the aim of this study was to explore how heating by warm bath and infrared radiation affects the circulations in the contralateral foot. Twelve healthy adults participated in this study and were randomly assigned to either placing the left foot in a warm bath or exposing it to infrared radiation for 10 minutes intervention every other day. The skin temperature (Temp) and skin blood flow (SBF) in the second metatarsal head of the contralateral foot were measured before and after the intervention. Results: The results showed that both Temp (Bath: from 29.05±3.56 °С to 31.03±4.14 °С; Infrared: from 29.98±3.86 °С to 31.07±3.92 °С) and SBF (Bath: from 62.26±48.12 PU to 97.76±63.90 PU; Infrared: from 63.37±39.88 PU to 85.27±47.62 PU) in the contralateral foot were significantly increased after heating in both tests (P<0.05). However, the contralateral SBF increased for 5 minutes after heating in warm bath test, but only for 1 minute in infrared radiation test. Conclusions: The results of this study show that both heating methods are the effective at increasing contralateral Temp and SBF, but the warm bath has a stronger residual thermal effect.
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The purpose of this work is to reveal the activation of natural defenses reserve in mice after treatment with different physico-chemical agents in vivo using previously developed technology of adaptive response induction. Physical agents were represented by X-rays, carbon ions, infrared light, He-Ne laser light, famine and chemical agents – by immunomodulator CaCl2 and anti-inflammatory drug ibuprofen. The following tasks were set: assessment of cytogenetic damage using a micronucleus test, the weight index of lymphoid organs (thymus and spleen) and the level of ROS production in whole blood through the method of luminol-dependent zymosan-induced chemiluminescence. SHK mice were irradiated according to the scheme of adaptive response. Analysis of data on the number of cytogenetic damage in bone marrow showed that pretreatment of the animals with all investigated agents and subsequent exposure to X-rays or carbon ions at a dose of 1.5 Gy has led to a decrease in radiosensitivity compared to the nontreated animals. Similar results were observed when analyzing weight index of lymphoid organs. Determination of level of ROS production has shown that the activation index calculated according to the relation of induced to spontaneous light area, was significantly higher in all groups of mice, indicating activation of the natural defenses reserve as compared to the group exposed only at a dose of 1.5 Gy. The obtained results confirm the assumption of revealing activation of the natural defense of the organism with the help of the adaptive response induction technology.
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Infrared devices and technologies are used for weight loss, cellulite treatment, body remodeling, beauty treatments, and wellness. Infrared (IR) is a type of electromagnetic radiation that has the ability to stimulate living tissues resulting in numerous biological responses. Exposure to IR is perceived as heat and their mechanism of action is related to the absorption of energy by photoacceptor molecules. Adverse reactions have also been documented. The studies, research papers and reviews of the last thirty years have been collected and examined and this review describes in more detail the main devices that use infrared: infrared thermal blankets, far-infrared thermal blanket, infrared lipo laser paddles, infrared lamps, far-infrared lamps, infrared saunas, far-infrared saunas, and infrared caps. IR thermal blanket improves blood circulation and the metabolism of the whole body, accelerate the detoxification, trigger the consumption of calories and fat burning. It is an alternative treatment to saunas but more effective. IR lipo laser paddles are a non-invasive alternative to traditional liposuction that helps to remove fat accumulated in specific areas of the body. IR lamps increase the absorption of cosmetic products, improve local blood circulation and relieve muscle and joint pain. IR saunas have a relaxing effect and the same effects of the thermal blanket and the IR lamps. IR caps can stimulate hair follicles and hair regrowth. Despite numerous studies, the precise mechanisms of action of the infrared need more research as well as the molecular targets that are directly or indirectly involved by their thermal effects and their non-thermal effects.
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The article analyzes the role of microcirculatory disorders in the pathogenesis of inflammatory complications (peri-implantitis) in patients with orthopedic constructions on dental implants and substantiates the possibility of a complex course application of low-intensity infrared laser therapy and low-frequency electrostatic therapy. It was shown that the initial state of patients with peri-implantitis is characterized by significantly low values of the level of general perfusion and its intensity, as well as the predominance of shunt mechanisms that reduce the values of the nutritive link of blood flow. The cause of the revealed disorders is the low level of functioning of the vasodilation mechanisms, caused by inflammatory and destructive processes in the peri-implant tissues. The use of a complex of physiotherapeutic exposure was characterized by a more pronounced corrective effect on the parameters of microcirculation and oxidative metabolism in comparison with standard dental treatment. The observed dynamics of microcirculatory systems of tissues of the peri-implant zone under the conditions of the complex influence of physiotherapeutic factors is aimed at the formation of adaptive reactions of local hemodynamics to the local needs of soft and bone tissues experiencing an inflammatory process around the implant, as well as strengthening the mechanisms of long-term adaptation of trophic relations in tissue peri-implant microregions. Taking into account the pathogenetic significance of microhemodynamic disorders in the formation of clinical manifestations of peri-implantitis, the revealed activating effect of the technology of the combined use of a laser and low-frequency electrostatic therapy serves as an objective proof of its therapeutic efficacy.
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Background: Diabetic foot ulcer is one of the chronic complications of diabetes mellitus caused by neuropathy, angiopathy and decreased endurance. The risk of amputation in patient with diabetes mellitus fifteen times greater compared to non-diabetic. Various efforts on diabetic foot wound care have been carried out but the results are still far from satisfactory. Until now, infrared and counseling effect on wound healing in diabetic foot cannot be explained. Objective: The purpose of this study was to examine the effect of infrared ray and counseling on diabetic foot ulcer healing process. Method: The research design was quasi-experimental design with posttest control group design, the population in this study were patients with grade 3 diabetic foot wounds, blood sugar 100-200 g/ dl, BMI 18.5 to 24.9, aged 35-55 years. Large sample in this study as many as 20 were divided into two groups, the control random sampling. The collection of data for the dependent variable using the observation sheet after the tenth day of treatment, which consists of the rate of growth of granulation, ankle brachial index and capillary refill time. Furthermore, the data were processed using non-parametric statistical significance level < 0.05. Result: The results showed that the infrared and counseling effect on the growth of granulation with a significance level (p = 0.0003), infrared and counseling influence ankle brachial index (p = 0.024), infrared and counseling effect on capillary and counseling effect on capillary refill time (p = 0.024). Conclusion: It can be concluded from this study that applying infrared and counseling has any impact on healing in diabetic foot ulcer, on the growth of granulation and improved blood in diabetic foot ulcers. Key words: Infrared Ray, Counseling, Foot Ulcer Healing.
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Background: Published literature reports significant improvements in pathological conditions, such as pain, blood dyscrasias, and cellulite, after using topical occlusive accessories containing particulate ceramic materials. Objective: In this study, we investigated whether the use of a topical occluding garment made with synthetic fibers embedded with powdered ceramic materials could be beneficial to patients suffering from edema of lower limb extremities. Materials and methods: The cohort comprised 30 volunteers of both genders who were divided into two study groups. The bioceramic (BC) group wore compressive socks made of fabrics with embedded ceramic powder for 8 h a day for 28 days. The placebo group wore compressive socks of the same material without ceramic powder. The efficacy of the treatment was quantified through weekly plethysmographic measurements. In addition, pain relief was evaluated through a visual analog scale (VAS). Results: Data showed a statistically significant reduction in the edema volume for the BC group compared with the placebo group: 78.9 ± 10.7 mL versus 41.3 ± 5.6 mL, p = 0.003. Further, there was also greater pain relief for the BC group when compared with the placebo group, with a pain decrease of 7.0 ± 0.2 U versus 3.3 ± 0.2 U, respectively, on the VAS from 0 to 10 (p = 0.024). Conclusions: The topical occlusive therapy with compressive socks containing infrared-emitting ceramic particulate in its fabrics showed that they were more beneficial than the placebo garment in the treatment of edema of the inferior member extremities as well as in relief of associated pain.
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Non-invasive far infrared radiation (FIR) has been observed to improve the health of patients with coronary artery disease (CAD). Endothelial colony forming cells (ECFCs) contribute to vascular repair and CAD. The goal of this study was to uncover the role of FIR in ECFCs function and to reveal potential biomarkers for indication of FIR therapy in CAD patients. FIR significantly enhanced in vitro migration (transwell assay) and tube formation (tube length) capacities in a subpopulation of CAD ECFCs. Clinical parameters associated with the responsiveness of ECFCs to FIR include smoking and gender. ECFCs from CAD patients that smoke did not respond to FIR in most cases. In contrast, ECFCs from females showed a higher responsiveness to FIR than ECFCs from males. To decipher the molecular mechanisms by which FIR modulates ECFCs functions, regardless of sex, RNA sequencing analysis was performed in both genders of FIR-responsive and FIR-non/unresponsive ECFCs. Gene Ontology (GO) analysis of FIR up-regulated genes indicated that the pathways enriched in FIR-responsive ECFCs were involved in cell viability, angiogenesis and transcription. Small RNA sequencing illustrated 18 and 14 miRNAs that are up- and down-regulated, respectively, in FIR-responsive CAD ECFCs in both genders. Among the top 5 up- and down-regulated miRNAs, down-regulation of miR-548aq-3p in CAD ECFCs after FIR treatment was observed in FIR-responsive CAD ECFCs by RT-qPCR. Down-regulation of miR-548aq-3p was correlated with the tube formation activity of CAD ECFCs enhanced by FIR. After establishment of the down-regulation of miR-548aq-3p by FIR in CAD ECFCs, we demonstrated through overexpression and knockdown experiments that miR-548aq-3p contributes to the inhibition of the tube formation of ECFCs. This study suggests the down-regulation of miR-548aq-3p by FIR may contribute to the improvement of ECFCs function, and represents a novel biomarker for therapeutic usage of FIR in CAD patients.
Chapter
Far infrared radiation thermotherapy (FIRT) is one of the few effective conservative treatments for chronic extremity lymphedema. FIRT combined with bandaging is effective in reducing the amount of edema, skin thickness, and size of the affected limb. A distinctive effect of FIRT/bandaging is reduction in the frequency of dermatolymphangioadenitis. FIRT reduces tissue fibrosis and improves skin elasticity. The mechanisms by which FIRT reduces chronic lymphedema include increasing the biological effects of the microcirculation of lymph and blood in the skin and enhancing tissue immune function. FIRT has been shown over 5 years of follow-up to be a safe means of treating malignant tumors.
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Purpose This study aims to test the effects of Celliant armbands on grip strength in subjects with chronic wrist and elbow pain. Celliant® is a functional textile fabric containing minerals that emit infrared radiation (IR) in response to body heat. IR-emitting fabrics have biological effects including the reduction of pain and inflammation and the stimulation of muscle function. Design/methodology/approach A randomized placebo-controlled trial recruited 80 subjects (40 per group) with a six-month history of chronic wrist or elbow pain (carpal tunnel syndrome, epicondylitis or arthritis) to wear an armband (real Celliant or placebo fabric) on the affected wrist or elbow for two weeks. Grip strength was measured by a dynamometer before and after the two-week study. Findings For the placebo group, the mean grip strength increased from 47.95 ± 25.14 (baseline) to 51.69 ± 27.35 (final), whereas for the Celliant group, it increased from 46.3 ± 22.02 to 54.1 ± 25.97. The mean per cent increase over the two weeks was +7.8% for placebo and +16.8% for Celliant (p = 0.0372). No adverse effects was observed. Research limitations/implications Limitations include the wide variation in grip strength in the participants at baseline measurement, which meant that only the percentage increase between baseline and final measurements showed a significant difference. Moreover, no subjective measurements of pain or objective neurophysiology testes was done. Practical implications Celliant armbands are easy to wear and have not been shown to produce any adverse effects. Therefore, there appears to be no barrier to prevent widespread uptake. Social implications IR-emitting textiles have been studied for their beneficial effects, both in patients diagnosed with various disorders and also in healthy volunteers for health and wellness purposes. Although there are many types of textile technology that might be used to produce IR-emitting fabrics, including coating of the fabric with a printed layer of ceramic material, incorporating discs of mineral into the garment, the authors feel that incorporating ceramic particles into the polymer fibers from which the fabric is woven is likely to be the most efficient way of achieving the goal. Originality/value Celliant armbands appear to be effective in painful upper limb inflammatory disorders, and further studies are warranted. The mechanism of action is not completely understood, but the hypothesis that the emitted IR radiation is absorbed by nanostructured intracellular water provides some theoretical justification.
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Far infrared radiation has an important effect on the growth of organisms. In order to explore the effect on promoting wound healing by far infrared fabrics, four kinds of fabrics with different far infrared emissivity were selected. According to the emissivity of the far infrared fabrics in the wearing state, the fabrics were coated outside the cell culture dish. Keratinocyte HaCaT and vein endothelial cell Huvec were selected as wound healing related epithelial cells. The proliferation and migration of the two kinds of cells were tested by four kinds of fabrics. The results of cell experiment showed that far infrared radiation can significantly promote the proliferation and migration of HaCaT and Huvec epithelial cells related to wound healing. The results showed that the longer the time of far infrared radiation, the more significant the promotion of HaCaT and Huvec cell proliferation and migration. The far infrared emissivity of four kinds of fabrics and their differences in promoting epidermal blood perfusion were involved in the analysis together with their effects on cell growth. The results showed that tea carbon fabric had the highest far infrared emissivity, the highest promotion of epidermal blood flow, and the most significant promotion of cell proliferation. In a certain range, the higher the far infrared emissivity and the longer the wearing time, the stronger the promotion of the proliferation and migration of HaCaT and Huvec epithelial cells. Therefore, from the cellular level, it is considered that far infrared fabrics can promote wound healing.
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Far-infrared ray (FIR) is an electromagnetic wave that produces various health benefits against pathophysiological conditions, such as diabetes mellitus, renocardiovascular disorders, stress, and depression etc. However, the therapeutic application on the FIR-mediated protective potentials remains to be further extended. To achieve the better understanding on FIR-mediated therapeutic potentials, we summarized additional findings in the present study that exposure to FIR ameliorates stressful condition, memory impairments, drug dependence, and mitochondrial dysfunction in the central nervous system. In this review, we underlined that FIR requires modulations of janus kinase 2 / signal transducer and activator of transcription 3 (JAK2/STAT3), nuclear factor E2-related factor 2 (Nrf-2), muscarinic M1 acetylcholine receptor (M1 mAChR), dopamine D1 receptor, protein kinase C δ gene, and glutathione peroxidase-1 gene for exerting the protective potentials in response to neuropsychotoxic conditions.
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Free tissue transfer, including skin flaps, is an important procedure in reconstructive surgery. During transfer of skin flaps, there is an inevitable period of ischemia. Prolonged ischemia causes significant damage and is associated with flap failure.The tolerance of tissue for ischemia increases by a process called thermal preconditioning, which can be obtained by increasing skin temperatures to supra-physiological levels. This study investigated the effect of water-filtered infrared-A irradiation (wIRA) on skin temperature and skin blood flow of the abdominal wall. Skin temperature and skin blood flow were measured with respectively, infrared thermography and scanning laser Doppler imaging. WIRA irradiation of the abdominal wall resulted in supra-physiological skin temperatures and up to a 10-fold increase in skin blood flow. No thermal discomfort during or after wIRA irradiation was registered. It is concluded that water-filtered infrared-A irradiation is a potential method for thermal preconditioning of skin flaps.
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Lack of randomised controlled trials makes it difficult to assess the efficacy of hyperbaric oxygen in many diseases. Side effects are usually mild but can be life threatening. Clear evidence of benefit has been found in decompression sickness and a few other conditions. Much work remains to be done to establish the timing, indications, and therapeutic regimens required to obtain the best clinical and cost effective results. The cellular, biochemical, and physiological mechanisms by which hyperbaric oxygen achieves beneficial results are not fully established.
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To assess microcirculatory impairment and alterations of the skin oxygen supply in diabetic patients with foot at risk. This study evaluated skin blood flow in 21 type 2 diabetic patients with a foot at risk (defined as a foot with neuropathy but without ulceration or previous ulcerations), 20 type 2 diabetic patients without foot lesions or neuropathy, and 21 normal subjects as a control group. The skin blood flow was determined by measuring the transcutaneous oxygen pressure (TcPO(2)) at the dorsum of the foot in supine and sitting position. The clinical assessment included standard measures of peripheral and autonomic neuropathy, but peripheral vascular disease was excluded by Doppler ultrasound. In supine position, TcPO(2) was significantly reduced (means +/- SE) in diabetic patients with foot at risk (6.04 +/- 0.52 kPa) compared with diabetic (7.14 +/- 0.43 kPa, P = 0.035) and nondiabetic (8.10 +/- 0.44 kPa, P = 0.01) control subjects. The sitting/supine TcPO(2) difference was higher in diabetic subjects with foot at risk (3.13 +/- 0.27 kPa) compared with both diabetic (2.00 +/- 0.18, P = 0.004) and nondiabetic (1.77 +/- 0.15 kPa, P = 0.0003) control subjects. The mean sitting/supine ratio was 1.70 +/- 0.12 in diabetic patients with foot at risk, 1.32 +/- 0.04 in diabetic control subjects, and 1.25 +/- 0.03 in nondiabetic control subjects (P = 0.007). The sitting/supine TcPO(2) ratio was negatively correlated with the heart rate variation coefficient at rest (r = -0.32, P = 0.044) and at deep respiration (r = -0.31, P = 0.046). Our data indicate that skin oxygen supply is reduced in type 2 diabetic patients with foot at risk. This is probably due to an impaired neurogenic blood flow regulation and may contribute to capillary hypertension, followed by disturbed endothelial function leading to edema and skin damage of the foot. The determination of TcPO(2) appears to be a useful tool in screening type 2 diabetic patients for foot at risk.
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Despite the known major role of skin blood vessel innervation in blood flow control, particularly in disease, little information on the co-innervation of blood vessels by sensory and autonomic fibers and the relationships of these fibers to one another is available. To fill this gap, we performed a light and electron microscopic analysis of the innervation of skin vessels by sensory and autonomic fibers by using the rat and monkey lower lips as a model. In rats, double-labeling immunocytochemistry revealed that combinations of fibers immunoreactive for substance P (SP) and dopamine-beta-hydroxylase (DbetaH), SP and vesicular acetylcholine transporter (VAChT), as well as DbetaH and VAChT occurred only around blood vessels in the lower dermis. All fiber types travelled in parallel and in close proximity to one another. In the upper dermis, blood vessels were innervated by SP-containing fibers only. Although nerve terminals displayed synaptic vesicles, synaptic specializations were never observed, suggesting that, in this territory, these fibers do not establish synaptic contacts. Quantification of the distance between the various immunoreactive terminals and their presumptive targets (smooth muscle cells and endothelial cells) revealed that both sympathetic and parasympathetic fibers were significantly closer to the endothelial cell layer and smooth muscle cells compared with sensory fibers. In monkeys, double-labeling immunocytochemistry was performed for SP-DbetaH and SP-VAChT only. The results obtained are similar to those found in rats; however, the fiber density was greater in monkeys. Our findings suggest that the regulation of skin microcirculation might be the result of the coordinated functions of sensory and autonomic fibers.
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To determine the efficacy of ceramic impregnated gloves in the treatment of Raynaud's syndrome. Double-blind, placebo-controlled study. Teaching hospital outpatient clinic. Ninety-three patients meeting the "Pal" criteria for Raynaud's syndrome. Treatment period of three months with use of ceramic-impregnated gloves. Primary end points: Pain visual analogue scale ratings and diary; Disabilities of the Arm, Shoulder, Hand questionnaire; Jamar grip strength; Purdue board test of hand dexterity. Secondary end points: Infrared skin temperature measurements; seven-point Likert scale rating of treatment. In 60 participants with complete data, improvements were noted in the visual analogue scale rating (p=0.001), DASH score (p=0.001), Jamar grip strength (p=0.002), infrared skin fingertip temperature (p=0.003), Purdue hand dexterity test (p=0.0001) and the Likert scale (p=0.001) with ceramic gloves over the placebo cotton gloves. The ceramic-impregnated "thermoflow" gloves have a clinically important effect in Raynaud's syndrome.
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The biological effects of far-infrared ray (FIR) on whole organisms remain poorly understood. The aim of our study was to investigate not only the hyperthermic effect of the FIR irradiation, but also the biological effects of FIR on wound healing. To evaluate the effect of FIR on a skin wound site, the speed of full-thickness skin wound healing was compared among groups with and without FIR using a rat model. We measured the skin wound area, skin blood flow, and skin temperature before and during FIR irradiation, and we performed histological inspection. Wound healing was significantly more rapid with than without FIR. Skin blood flow and skin temperature did not change significantly before or during FIR irradiation. Histological findings revealed greater collagen regeneration and infiltration of fibroblasts that expressed transforming growth factor-beta1 (TGF-beta1) in wounds in the FIR group than in the group without FIR. Stimulation of the secretion of TGF-beta1 or the activation of fibroblasts may be considered as a possible mechanisms for the promotive effect of FIR on wound healing independent of skin blood flow and skin temperature.
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The aim of the present study was to determine whether repeated 60 degrees C sauna treatment improves cardiac arrhythmias in chronic heart failure (CHF) patients, because ventricular arrhythmias are an important therapeutic target in CHF. Thirty patients (59+/-3 years) with New York Heart Association functional class II or III CHF and at least 200 premature ventricular contractions (PVCs)/24 h assessed by 24-h Holter recordings were studied. They were randomized into sauna-treated (n=20) or non-treated (n=10) groups. The sauna-treated group underwent a 2-week program of a daily 60 degrees C far infrared-ray dry sauna for 15 min, followed by 30 min bed rest with blankets, for 5 days per week. Patients in the non-treated group had bed rest in a temperature-controlled room (24 degrees C) for 45 min. The total numbers of PVCs/24 h in the sauna-treated group decreased compared with the non-treated group [848+/-415 vs 3,097+/-1,033/24 h, p<0.01]. Heart rate variability (SDNN, standard deviation of normal-to-normal beat interval) increased [142+/-10 (n=16) vs 112+/-11 ms (n=8), p<0.05] and plasma brain natriuretic peptide concentrations decreased [229+/-54 vs 419+/-110 pg/ml, p<0.05] in the sauna-treated group compared with the non-treated group. Repeated sauna treatment improves ventricular arrhythmias in patients with CHF.
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Lasers are now widely used for treating numerous cutaneous lesions, for scar revision (hypertrophic and keloid scars), for tissue welding, and for skin resurfacing and remodeling (wrinkle removal). In these procedures lasers are used to generate heat. The modulation of the effect (volatilization, coagulation, hyperthermia) of the laser is obtained by using different wavelengths and laser parameters. The heat source obtained by conversion of light into heat can be very superficial, yet intense, if the laser light is well absorbed (far-infrared:CO2 or Erbium:Yttrium Aluminum Garnet [Er:YAG] lasers), or it can be much deeper and less intense if the laser light is less absorbed by the skin (visible or near-infrared). Lasers transfer energy, in the form of heat, to surrounding tissues and, regardless of the laser used, a 45–50°C temperature gradient will be obtained in the surrounding skin. If a wound healing process exists, it is a result of live cells reacting to this low temperature increase. The generated supraphysiologic level of heat is able to induce a heat shock response (HSR), which can be defined as the temporary changes in cellular metabolism. These changes are rapid and transient, and are characterized by the production of a small family of proteins termed the heat shock proteins (HSP). Recent experimental studies have clearly demonstrated that HSP 70, which is over-expressed following laser irradiation, could play a role with a coordinated expression of other growth factors such as transforming growth factor (TGF)-ß. TGF-ß is known to be a key element in the inflammatory response and the fibrogenic process. In this process, the fibroblasts are the key cells since they produce collagen and extracellular matrix. In conclusion, the analysis of the literature, and the fundamental considerations concerning the healing process when using thermal lasers, are in favor of a modification of the growth factors synthesis after laser irradiation, induced by an HSR. An extensive review of the different techniques and several clinical studies confirm that thermal lasers could effectively promote skin wound healing, if they are used in a controlled manner.
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Background/Aims: Several physical agents such as low-energy lasers have been used in the treatment of chronic skin ulcers. This study was performed to investigate potential effects of a newly-developed, specific near-infrared light source on wound repair. Methods: Cultured human keratinocytes, endothelial cells and fibroblasts were exposed to the light, and the production of transforming growth factor (TGF)-β1 and matrix metalloproteinase (MMP)-2 was examined by enzyme immunoassay, zymography and reverse transcription polymerase chain reaction. Incisional wounds were created in ICR and db/db diabetic mice and the effect of irradiation on wound closure was followed photographically. Results: The TGF-β1 and MMP-2 content of the medium of cultured cells was significantly elevated after irradiation. The amount of MMP-2 mRNA extracted from irradiated fibroblasts was also upregulated. Negative results in thermal controls suggested that the action of the light was athermic in nature. In animal models, the rate of wound closure was significantly accelerated by repeated exposures. Conclusion: Near-infrared irradiation potentially enhances the wound healing process, presumably by its biostimulatory effects.
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Honokiol, a compound extracted from the Chinese medicinal herb Magnolia officinalis, has a strong antioxidant effect on the inhibition of lipid peroxidation in rat heart mitochondria. To investigate the protective effect of honokiol on hepatocytes from peroxidative injury, oxygen consumption and malondialdehyde formation for in vitro iron-induced lipid peroxidation were assayed, and the mitochondrial respiratory function for in vivo ischemia-reperfusion injury were evaluated in rat liver, respectively. The inhibitory effect of honokiol on oxygen consumption and malondialdehyde formation during iron-induced lipid peroxidation in liver mitochondria showed obvious dose-dependent responses with a concentration of 50% inhibition being 2.3 × 10−7M and 4.96 × 10−7M, respectively, that is, 550 times and 680 times more potent than α-tocopherol, respectively. When rat livers were introduced with ischemia 60 min followed by reperfusion for 60 min, and then pretreated with honokiol (10 ug/kg BW), the mitochondrial respiratory control ratio (the quotient of the respiration rate of State 3 to that of State 4) and ADP/O ratio from the honokiol-treated livers were significantly higher than those of non-treated livers during reperfusion. The dose-dependent protective effect of honokiol on ischemia-reperfusion injury was 10 μg-100 μg/Kg body weight. We conclude that honokiol is a strong antioxidant and shed insight into clinical implications for protection of hepatocytes from ischemia-reperfusion injury.
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Contrary to previous presumption, accumulated evidence indicates that far-infrared rays are biologically active. A small ceramic disk that emits far-infrared rays (4-16 microns) has commonly been applied to a local spot or a whole part of the body for exposure. Pioneering attempts to experimentally analyze an effect of acute and chronic radiation of far-infrared rays on living organisms have detected a growth-promoting effect in growing rats, a sleep-modulatory effect in freely behaving rats and an insomiac patient, and a blood circulation-enhancing effect in human skin. Questionnaires to 542 users of far-infrared radiator disks embedded in bedclothes revealed that the majority of the users subjectively evaluated an improvement of their health. These effects on living organisms appear to be non-specifically triggered by an exposure to far-infrared rays, which eventually induce an increase in temperature of the body tissues or, more basically, an elevated motility of body fluids due to decrease in size of water clusters.
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Unrestrained male rats continuously exposed to far-infrared radiation exhibited a significant increase in slow wave sleep (SWS) during the light period but not in the dark period. The change was largely due to the elevated occurrence of SWS episodes but not to the prolongation of their duration. Paradoxical sleep was not affected throughout the observation period except for a significant decrease at the end of the dark period. Thus the far-infrared radiation exerted a sleep modulatory effect closely related to the circadian activity-rest cycle.
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The gaseous free radical nitric oxide is an important biologic mediator with physiologic and pathophysiologic roles in nearly every organ system. Because of its unique biologic activity, unusual chemical structure, and unprecedented mechanisms of action, nitric oxide, arguably more than any other natural product, has opened new avenues to investigate cellular processes. Nitric oxide is generated in biologic tissues by specific nitric oxide synthases that metabolize arginine and molecular oxygen to citrulline and nitric oxide. Besides its function as a diffusible messenger in the vasculature and in neurons, nitric oxide also plays a key role in innate immunity and inflammation. Recent progress has allowed the identification of the nitric oxide pathway in several cell types that reside in the skin, including keratinocytes, melanocytes, Langerhans cells, fibroblasts, and endothelial cells. Convincing evidence suggests that nitric oxide synthesis in these cells can be modulated by calcium-mobilizing agonists as well as diverse inflammatory and immune stimuli, and thereby contributes to the pathogenesis of several human skin diseases. Characterization of these intrinsic and extrinsic regulatory stimuli of nitric oxide synthesis has afforded substantial insights into the role of nitric oxide in inflammatory, hyperproliferative, and autoimmune skin diseases, as well as skin cancer, and may ultimately form the basis for future therapeutic intervention. The demonstrable and potential roles of nitric oxide in skin disease pathogenesis and treatment are the subjects of this review.
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To examine whether and how local somatothermal stimulation inhibits the function of the sphincter of Oddi (SO) in humans and in animals with different types of SO, we measured the activity of SO in anesthetized cats and rabbits by using continuously perfused open-tip manometric methods. Local somatothermal stimulation was achieved by applying an electroheating rod 0.5 cm away from the skin area near the right subcostal region. A heating pad was applied to the corresponding area in patients undergoing endoscopic retrograde cholangiopancreatography and biliary manometry. The motility of the biliary tract in cats, in terms of gall bladder pressure, tonic and phasic contraction pressure and frequency of SO before and during local heat were significantly different, respectively. The local heat-induced SO relaxation was not inhibited by pretreatment with atropine, propranolol, phentolamine or anti-cholecystokinin-octapeptide, but was almost completely blocked by infiltration of local anesthetics. Pretreatment with a nitric oxide synthesis inhibitor also blocked the relaxation, which was reversed by pretreatment with L-arginine, but not by D-arginine. The inhibition of SO motility by local heat in rabbits was also blocked by pretreatment with L-NAME, and this blockade was reversed by L-arginine. Application of local heat on patients demonstrated obvious inhibitory SO responses. We conclude that local somatothermal stimulation inhibits the SO motility in animals with different types of SO through the activation of heat-sensitive neural release of nitric oxide. This procedure may represent a simplified approach for the treatment of diseases with hypofunction of the L-arginine/NO pathway.
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To evaluate the effect of irradiation of far infrared rays (FIR), the growth of spontaneous mammary tumours of SHN mice was compared among 3 groups: the control was kept until the end of experiment on the normal rack in the absence of FIR and Experimental group I was constantly exposed to FIR. Experimental group Il was raised as the control followed by movement to the FIR rack after mammary tumour appearance. While there was little difference between the control and Experimental group I in mammary tumour growth for 16 days, Experimental group II was significantly lower than the control in this parameter. Furthermore, the percentage of rapidly growing tumours showing greater than 200% of growth rate was apparently lower in Experimental group II. Associated with this, epidermal growth factor receptor expression in mammary tumours, anterior pituitary weight and serum leptin level were significantly decreased in Experimental group II. The findings suggest that whole-body FIR irradiation at ambient temperature could be a possible way of a hyperthermic therapy for tumours.
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In the future, the indications for HBO therapy in acute peripheral ischemic injuries will likely be based on objective criteria rather than, as at present, on clinical diagnoses alone. This chapter offers objective criteria for using HBO in crush injuries and compartment syndromes. The pathophysiology of ATPI are well defined. Hyperbaric oxygen mediates the effects of ATPI through four mechanisms: hyperoxygenation, vasoconstriction, reperfusion, and host factors. The cost benefits of using HBO will be substantial, since complications from ATPI are very expensive. As objective criteria replace the presently used subjective criteria, hyperbaric oxygen therapy will become an integral part of trauma management of these injuries.
Article
The effects of chronic exposure to far-infrared ray (FIR) on reproduction, growth, behaviour, survival time and some related parameters were examined in SHN mice. The reproductive parameters differed slightly between the females on the normal racks and those on the FIR racks, which emitted FIR from the ceiling. The age and body weight on the day of vaginal opening was lower in the experimental mice born and maintained on the FIR rack than in the control on the normal rack. In both sexes, the levels of urinary components in the experimental group was significantly higher than the control at 6-7 months of age. Spontaneous motor activity of females during the light and dark phases were higher and lower, respectively, in the experimental group than the control. The survival rate was significantly higher in the experimental group than the control. These findings suggest that FIR has 'normalization effects' on the organisms.
Article
SV129 or C57BL/6 mice were exposed to hyperbaric oxygenation (HBO, 5 days, 1 h every day, 100% O(2) at 3 atm absolute). One day after the 5th HBO session focal cerebral ischemia was induced. In SV129 mice, HBO induced tolerance against permanent focal cerebral ischemia (n=42, mean infarct volume reduction 27%, P=0.001), but not against transient (30 or 60 min) focal cerebral ischemia. In the C57BL/6 strain of mice, HBO did not induce tolerance against focal cerebral ischemia, even when the duration of ischemia or the HBO protocol were modified. For the first time we demonstrate that HBO can induce tolerance to focal cerebral ischemia, but this effect is strain dependent.
Article
There are only a few reliable objective methods of diagnosing peripheral neuronal damage suitable for routine use; the most important is based on measurement of nerve conduction velocity, which only shows changes when severe disturbances are already present. However, it is precisely at this stage that the possibilities of therapy are no longer satisfactory. As small fibres are affected earlier in the course of most forms of PNP than the large ones, assessment of afferent as well as efferent C-fibre function gains importance in the management of this widespread disease. In assessment of autonomic dysfunction, variability of the heartbeat with deep breathing or the Valsalva manoeuvre is a good and generally accepted test, although not strongly associated with other PNP test abnormalities. However, axonal degeneration starts in the most distal parts of the axon due to impaired axonal transport. Therefore, the longest C-fibres, i.e. in the lower extremities, are affected first, and incipient changes are most prominent there. For this reason HLDF, a reflex response of the skin blood flow stimulated by heat, has advantages in assessment of early C-fibre dysfunction. Considering the fact that the afferent and efferent sympathetic C-fibres are involved in regulation of microcirculation, the skin blood flow regulation is investigated by means of laser Doppler flowmetry. The microcirculation is stimulated by heat and the reaction of microcirculation is assessed as a value for the function of afferent and efferent (sympathetic) C-fibres. The results of this method are in close correlation with electrophysiologic tests, which is not achieved with sudomotor function.
Article
Several physical agents such as low-energy lasers have been used in the treatment of chronic skin ulcers. This study was performed to investigate potential effects of a newly-developed, specific near-infrared light source on wound repair. Cultured human keratinocytes, endothelial cells and fibroblasts were exposed to the light, and the production of transforming growth factor (TGF)-beta1 and matrix metalloproteinase (MMP)-2 was examined by enzyme immunoassay, zymography and reverse transcription polymerase chain reaction. Incisional wounds were created in ICR and db/db diabetic mice and the effect of irradiation on wound closure was followed photographically. The TGF-beta1 and MMP-2 content of the medium of cultured cells was significantly elevated after irradiation. The amount of MMP-2 mRNA extracted from irradiated fibroblasts was also upregulated. Negative results in thermal controls suggested that the action of the light was athermic in nature. In animal models, the rate of wound closure was significantly accelerated by repeated exposures. Near-infrared irradiation potentially enhances the wound healing process, presumably by its biostimulatory effects.
Article
In human skin, the vasodilator response to local heating includes a sensory nerve-dependent peak followed by a nadir and then a slower, nitric oxide-mediated, endothelium-dependent vasodilation. To investigate whether chronic sympathectomy diminishes this endothelium-dependent vasodilation, we studied individuals who had previously undergone surgical T(2) sympathectomy (n = 9) and a group of healthy controls (n = 8). We assessed the cutaneous vascular response (laser-Doppler) to 30 min of local warming to 42.5 degrees C on the ventral forearm (no sympathetic innervation) and the lower legs (sympathetic nerves intact). Lower body negative pressure (LBNP) was measured to confirm sympathetic denervation. During local warming in sympathectomized individuals, vascular conductance reached an initial peak at both sites [achieving 1.73 +/- 0.22 laser-Doppler units (LDU)/mmHg in the forearm and 1.92 +/- 0.21 LDU/mmHg in the leg]. It then decreased to a nadir in the innervated leg [to 1.77 +/- 0.23 LDU/mmHg (P < 0.05)] but not in the sympathectomized arm (1.69 +/- 0.21 LDU/mmHg; P > 0.10). The maximal vasodilation seen during the slower phase was not different between limbs or between groups. Furthermore, LBNP caused a 44% reduction in forearm vascular conductance (FVC) in control subjects, but FVC did not decrease significantly in sympathectomized individuals, confirming sympathetic denervation. These data indicate that endothelial function in human skin is largely preserved after sympathectomy. The altered pattern of the response suggests that the nitric oxide-dependent portion may be accelerated in sympathectomized limbs.
Article
Ischemic preconditioning is a protective endogenous mechanism to reduce ischemia/reperfusion injury and is defined as a brief period of ischemia the authors term "preclamping." This is followed by tissue reperfusion and is believed to increase the ischemic tolerance. The objective of this study was to determine whether acute remote ischemic preconditioning, which has been reported to be successful for other organs, such as the heart, kidney, intestine, and liver, will also result in an enhancement of survival in flaps, and whether remote ischemic preconditioning is as effective as preclamping. Forty male Wistar rats were divided into four experimental groups. An extended epigastric adipocutaneous flap (6 x 10 cm) was raised, based on the left superficial epigastric artery and vein. In the control group, a 3-hour flap ischemia was induced. In the preclamping group, a brief ischemia of 10 minutes was induced by clamping the flap pedicle, followed by 30 minutes of reperfusion. Ischemia of the right hind limb was induced in the femoral ischemia group by clamping the femoral artery and vein for 10 minutes after flap elevation. The limb was then reperfused for 30 minutes. Thereafter, flap ischemia was induced as in the control group. A similar protocol was used in the tourniquet group. A tourniquet was used to induce hind-limb ischemia. The experiment was then performed as in the femoral ischemia group. Mean flap necrosis area was assessed for all groups on the fifth postoperative day using planimetry software. Average flap necrosis area was 68.2 +/- 18.1 percent in the control group, 11 +/- 8.38 percent in the preclamping group, 12.5 +/- 5.83 percent in the femoral ischemia group, and 24 +/- 11.75 percent in the tourniquet group. All preconditioned animals demonstrated a significantly lower area of flap necrosis than the control group (p < 0.001, one-way analysis of variance, post hoc Tukey's test). The data show that ischemic preconditioning and enhancement of flap survival can be achieved not only by preclamping of the flap pedicle but also by induction of an ischemia/reperfusion event in a body area distant from the flap before harvest. These findings indicate that remote ischemic preconditioning is a systemic phenomenon, leading to an enhancement of flap survival. The exact mechanism is not yet completely understood. The data suggest that remote ischemic preconditioning could be performed simultaneously with flap harvest in the clinical setting, resulting in an improved flap survival without prolongation of the operation. This may decrease the rate of partial flap loss or fat necrosis, especially in high-risk groups such as smokers, those with irradiated tissues, and obese patients.
Article
Recent reports have focused on the mechanisms of the action of electro-acupuncture stimulation (EAS) in the regulation of blood flow to different tissues. In the knee joint, blood flow is known to be modulated mainly by sympathetic postganglionic fibers, but recently the release or induction of nitric oxide (NO) synthesis in response to electrical stimulation has also been suggested. Therefore, a direct observation of the microcirculation is needed to further understand the mechanism by which blood flow is regulated by somatic afferent stimulation. In the present study, the effects of EAS to the vastus medialis muscle on systemic hemodynamics and the knee joint microcirculation were observed in vivo using a real-time confocal laser-scanning microscope system (CLMS). Electrical stimulation (5 mA, 0.5 ms, 5 Hz) was applied for 30 min using a pair of acupuncture needles introduced into the vastus medialis muscle. To clarify a plausible involvement of NO in the responses to EAS, the stimulus was applied either in the presence or absence of Nω-nitro-L-arginine methyl ester (L-NAME). Stimulation to either the muscle or the skin of the thigh after blockade of neuromuscular transmission was performed to determine the involvement of muscle contraction during EAS treatment. The changes in mean arterial pressure (MAP) and diameter of the arterioles supplying the knee joint were monitored continuously until 60 min poststimulus.
Article
Low-intensity laser irradiation has been shown to induce wound healing in conditions of reduced microcirculation, which is in part explained by systemic effects. We therefore investigated such a potential systemic effect of low-intensity laser irradiation on skin blood circulation in patients with diabetic microangiopathy. Patients with diabetic microangiopathy were randomized to receive either a single helium-neon (HeNe, 632.8 nm) low-intensity laser irradiation with a dose of 30 J/cm(2) or a sham irradiation over the forefoot region in a double-blind, placebo-controlled clinical study. Skin blood circulation by means of temperature recordings over forefoot regions was detected by infrared thermography. Following a single transcutaneous low-intensity laser irradiation, a rise in skin temperature in both feet of the subjects in the laser group was noted, whereas in both feet of the subjects in the placebo group a drop in skin temperature occurred. The baseline-adjusted skin temperature 15 min after the end of the irradiation was significantly higher in the laser-treated forefeet compared to the placebo-"treated" forefeet (p < 0.0001); the baseline-adjusted difference in the temperature was 1.94 +/- 0.35 degrees C. Simultaneously, the baseline-adjusted skin temperature was significantly higher in the laser-untreated forefeet compared to the placebo-"untreated" forefeet (P < 0.0001); the baseline-adjusted difference was 1.70 +/- 0.33 degrees C. Our data show a significant increase in skin circulation due to athermic laser irradiation in patients with diabetic microangiopathy and point to the possibility of inducing systemic effects.
Article
Light or electromagnetic radiation has been reported to enhance wound healing. The use of selected spectra, including infrared and microwave, has been described; however, no studies to date have examined the potential benefit of combining these spectra. In this study, a device that emits electromagnetic radiation across both the infrared and microwave ranges was used. To test the effects of this unique electromagnetic radiation spectrum on wound healing, two clinically relevant wound-healing models (i.e., tensile strength of simple incisions and survival of McFarlane flaps) were selected. After the creation of a simple full-thickness incision (n = 35 rats) or a caudally based McFarlane flap (n = 33 rats), animals were randomly assigned to one of three treatment groups: untreated control, infrared, or combined electromagnetic radiation. Treatment was administered for 30 minutes, twice daily for 18 days in animals with simple incisions, and 15 days in animals with McFarlane flaps. The wound area or flap was harvested and analyzed, blinded to the treatment regimens. A p value of less than 0.05 obtained by analysis of variance was considered to be statistically significant. Animals receiving combined electromagnetic radiation demonstrated increased tensile strength (2.62 N/mm2) compared with animals receiving infrared radiation (2.36 N/mm2) or untreated controls (1.73 N/mm2, p < 0.001). Animals with McFarlane flaps receiving combined electromagnetic radiation had increased flap survival (78.0 percent) compared with animals receiving infrared radiation (69.7 percent) and untreated controls (63.1 percent, p < 0.01). Thus, combined electromagnetic radiation provided a distinct advantage in wound healing that might augment current treatment regimens.
Article
The idea that there might be sympathetic vasodilator nerves to skeletal muscle is an old concept that fits with the archaic 'fight or flight' model of the sympathetic nervous system. Clear evidence for vasodilator nerves to skeletal muscle began to emerge in animals during the 1930s, when stimulation of selected brainstem areas was shown to evoke hypertension, tachycardia and skeletal muscle vasodilation (i.e. the 'defense reaction'). By the 1940s and 1950s this idea was well established and it was shown in animals that the sympathetic dilator nerves to muscles were cholinergic. During this time, circumstantial evidence began to suggest the existence of sympathetic cholinergic vasodilator fibres in human skeletal muscle. In this context, the well- known forearm vasodilator response to mental stress was shown to be atropine-sensitive, and absent after surgical sympathectomy. However, while there was clear histological evidence for sympathetic cholinergic dilator fibres in animal muscle, such evidence was not seen in humans. Additionally, attempts to record from sympathetic dilator fibres human muscle have never demonstrated clear evidence for dilator nerve traffic, and many 'sympathetic dilator' responses are still present after local anaesthetic nerve block. More recently, the skeletal muscle dilator response to sympathoexcitatory manoeuvres in both humans and animals appears to be nitric oxide (NO)-dependent. While there are clearly atropine-sensitive and NO-dependent dilator nerves to skeletal muscles in animals, our current thinking is that most 'sympathetic dilator' responses in human muscle are due to adrenaline or local cholinergic mechanisms acting to stimulate NO release from the vascular endothelium.
Article
This study was designed to test the hypotheses that local somatothermal stimulation on the left median nerve territory increases myocardial heat shock protein 70 and that preconditioning of rats with local somatothermal stimulation protects the hearts against subsequent ischemia-reperfusion injury. Local somatothermal stimulation was brought about by means of application of a heating rod over and above the left median nerve territory (1.5 cm proximal to the palm crease) in male Sprague-Dawley rats. After rats were treated with local somatothermal stimulation, the gene expression of heat shock protein 70 in regional muscle, heart, and liver was assessed by means of Western blotting and reverse transcription-polymerase chain reaction. In addition, durations of arrhythmia, mortality rates, and mitochondrial functions were compared between groups preconditioned with or without local somatothermal stimulation followed by subsequent myocardial ischemia-reperfusion injury. The results showed that the gene expression of heat shock protein 70 was upregulated in the muscle beneath the area of local somatothermal stimulation, as well as in the heart, although not in the liver. When animals were preconditioned with local somatothermal stimulation on the left median nerve territory followed by subsequent ischemia-reperfusion injury of the heart, there were significant decreases of creatine kinase level from the heart, duration of arrhythmia, mortality rate, and improved mitochondrial respiratory function compared with that seen in those without local somatothermal stimulation preconditioning. We conclude that local heat stress preconditioning on the left median nerve territory has a potential cardioprotective effect against subsequent ischemia-reperfusion injury.
Article
The thermoregulatory control of human skin blood flow is vital to the maintenance of normal body temperatures during challenges to thermal homeostasis. Sympathetic neural control of skin blood flow includes the noradrenergic vasoconstrictor system and a sympathetic active vasodilator system, the latter of which is responsible for 80% to 90% of the substantial cutaneous vasodilation that occurs with whole body heat stress. With body heating, the magnitude of skin vasodilation is striking: skin blood flow can reach 6 to 8 L/min during hyperthermia. Cutaneous sympathetic vasoconstrictor and vasodilator systems also participate in baroreflex control of blood pressure; this is particularly important during heat stress, when such a large percentage of cardiac output is directed to the skin. Local thermal control of cutaneous blood vessels also contributes importantly--local warming of the skin can cause maximal vasodilation in healthy humans and includes roles for both local sensory nerves and nitric oxide. Local cooling of the skin can decrease skin blood flow to minimal levels. During menopause, changes in reproductive hormone levels substantially alter thermoregulatory control of skin blood flow. This altered control might contribute to the occurrence of hot flashes. In type 2 diabetes mellitus, the ability of skin blood vessels to dilate is impaired. This impaired vasodilation likely contributes to the increased risk of heat illness in this patient population during exposure to elevated ambient temperatures. Raynaud phenomenon and erythromelalgia represent cutaneous microvascular disorders whose pathophysiology appears to relate to disorders of local and/or reflex thermoregulatory control of the skin circulation.
Article
This brief review highlights human studies on the role of nitric oxide (NO) and limb vasodilation conducted at the Mayo Clinic over the last 10 years. These studies have attempted to determine whether NO is responsible for the "unexplained" limb vasodilation seen with body heating, limb ischemia, exercise, and mental stress. Our findings are placed in context with data from others, and possible future areas of study are identified. Key words: skin blood flow, reactive hyperemia, exercise hyperemia, mental stress
Article
The effect of hyperbaric oxygen is known to increase survival of ischemic tissue but its mechanism is not fully understood. The purpose of this study was to evaluate the effect of hyperbaric oxygen on a rat musculocutaneous flap versus ischemia-reperfusion injury, focusing on the mechanism involving the expression of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) of endothelial cells and CD18 of neutrophils. A transverse rectus abdominis musculocutaneous (TRAM) flap (6 x 5 cm) supplied by a single superior epigastric vascular pedicle was elevated in 100 Sprague-Dawley rats. The rats were divided into 4 groups: group 0, sham (n = 10); group I, 4 hours of ischemia followed by reperfusion (n = 30); group II, 4 hours of ischemia and hyperbaric oxygen (100% oxygen, 2.5 atm absolute, during the last 90 minutes of ischemia before reperfusion) followed by reperfusion (n = 30); and group III, 4 hours of ischemia followed by reperfusion and hyperbaric oxygen (100% oxygen, 2.5 atm absolute, after reperfusion for 90 minutes; n = 30). The study consisted of gross examination for flap survival, histology, immunohistochemical staining, myeloperoxidase assay, flow cytometric study of CD18, and Northern blot analysis on ICAM-1 messenger ribonucleic acid expression. Gross measurement of the flap showed increased survival in groups II and III compared with group I (P < 0.05). The leukocytes adherent to the endothelium were counted at 24 hours and on day 5. Group I leukocytes were significantly increased compared with groups II and III (P < 0.05). The myeloperoxidase assay of TRAM flaps at 24 hours revealed a significant increase in group I compared with groups II and III (P < 0.05). The expression of CD18 was similar between groups I, II, and III. Immunohistochemical staining for ICAM-1 and Northern blot analysis on ICAM-1 messenger ribonucleic acid showed decreased expression in groups II and III compared with group I. Throughout the analysis, groups II and III did not show any significant differences. These results suggests that hyperbaric oxygen reduces the accumulation of leukocytes in the TRAM flap, but not enough to prevent adhesion of neutrophils on endothelial cells; ischemia-reperfusion injury increases the expression of CD18 and ICAM-1 and causes increased adhesion of leukocytes on the endothelium; hyperbaric oxygen does not alter the expression of CD18 but decreases the expression of ICAM-1; and the point of application for hyperbaric oxygen, whether applied before or after reperfusion, did not show any differences in outcome. In conclusion, the application of hyperbaric oxygen against ischemia-reperfusion injury increases flap survival and the beneficial effect may be explained by a protective mechanism involving downregulation of ICAM-1 on endothelial cells.
Article
Insufficient angiogenesis and microcirculatory intravascular clotting have been implicated in the pathophysiology of skin flap failure. Salvianolic acid B (Sal B), isolated from Salvia miltiorrhiza, has been reported to enhance angiogenesis in vitro. This study was aimed to determine the efficacy of Sal B on ischemia-reperfusion injury of the skin flap in Sprague-Dawley rats. Sal B was administered intraperitoneally 2 h before operation, and on the 2nd and 4th days after surgical elevation of an extended epigastric adipocutaneous flap (5 x 7 cm) in ketamine-anesthetized rats. Flap ischemia was achieved by ligating the right superficial epigastric artery and vein and clamping the left superficial epigastric artery and vein for 3 h and then released. Percentage of flap necrosis area (FNA) and plasma levels of aspartate aminotransferase, alanine aminotransferase, creatinine, and malondialdehyde were measured at 7 days after the operation. Animals were divided into six groups, including: vehicle, Sal B low dose (5 mg/kg), Sal B high dose (50 mg/kg) and each with [mesh(+)] or without mesh [mesh(-)] placement. In the three groups with mesh(+), FNA in control flaps was 53.7 +/- 6.9%, whereas low-dose and high-dose Sal B significantly improved flap survival with FNA 27.4 +/- 3.8% and 25.3 +/- 4.3%, respectively (P < 0.05, one-way ANOVA). In the three groups with mesh(-), control flaps were 35.9 +/- 4.5%, whereas high-dose Sal B also significantly improved flap survival with FNA 17.9 +/- 4.7% (P < 0.05, one-way ANOVA). There were no differences in aspartate aminotransferase, alanine aminotransferase, creatinine, or malondialdehyde between groups. We conclude that Sal B attenuates ischemia-reperfusion injury of skin flap, and provides therapeutic potential in reconstructive plastic surgery.