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Wound healing in the skin depends upon the availability of appropriate trace metals as enzyme cofactors and structural components in tissue repair. The present study is a part of a series of experimental investigations to examine the influence of Bentonite on skin wound healing. Surgically induced skin wounds in 48 young adult male rats were exposed topically to Bentonite (12 round wound and 12 incisional wound) and control wounds (12 round wound and 12 incisional wound) received de- ionized water only. Skin wounds (round and incisional) treated with Bentonite exhibited no significant difference in margins with erythema and edematous changes. Scab and wound debris was more extensive and persisted for at least 7 days after surgery in control group (P < 0.05). Skin wounds exposed to Bentonite exhibited a mild retarded re-epithelialization, the treatment wounds were characterized by a prominent central mass of inflammatory cells, cell debris and wound exudate. The intense infiltrate of lymphocytes, macrophages, monocytes and fibroblasts extended from the wound margin into the region of the panniculus carnosus muscle and hypodermis. Vascular dilatation and dermal oedema were prominent features of these wounds. External utilization of Bentonite for wound healing is safe and feasible, and we finalized that macroscopic healing of wound that treated by
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... Imbalances in the relative concentrations of the ions are potential causes of impaired wound healing. Therefore, the layered structure of bentonite can affect the cation-exchange capacity [16]. These valuable features make it as an interesting biomaterial for skin wound healing. ...
... The features of clay minerals could also be a driving force for healing. Positively-charged inter-layers of clay could absorb and deposit on the negatively-charged cells in the wound environment, improving the healing process [16]. Therefore, the wounds treated with the Carb gel containing CEB showed faster healing than other groups. ...
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Providing an appropriate treatment to accelerate wound healing after a burn is a challenging problem. Therefore, finding advanced and cost-effective products reducing the recovery time is essential. This study aimed to introduce a simple strategy for the preparation of a multifunctional dressing bearing natural-based materials for the treatment of burn wounds. Carbopol (Carb) gel was loaded with carnosine-enriched bentonite (CEB), and the wound healing potential was evaluated using a rat burn wound model. The acceptable physicochemical properties of Carb-CEB gel provided an appropriate media for improved fibroblast cell adhesion, migration, survival, and growth compared to the Carb gel alone. Furthermore, ferric reducing antioxidant potential (FRAP) assay revealed superior antioxidant activity of Carb-CEB than Carb (*P ≤ 0.05). Macroscopically, the wound healing rates of Carb and Carb-CEB were approximately 84 and 95%, respectively, confirming the significant role of CEB in accelerating the wound closure. Histological evaluation also showed better epithelialization, angiogenesis, and reduction in inflammatory cells in the rats treated with Carb-CEB compared to the controls. In Carb-CEB-treated wounds, the regenerated epidermis was thicker and the number of blood vessels increased significantly. Overall, in vitro and in vivo studies suggested that Carb-CEB could be introduced as a promising wound dressing for further study of wound healing. Graphical abstract
... Bentonite is a clay mineral mostly comprised of smectite, in which the predominant composition of smectite in the bentonite is montmorillonite (Mt) (Kaufhold et al., 2002). It also has been applied to the development of health-related products, such as functional foods, cosmetics, and pharmaceuticals (Allo and Murray, 2004;Emami-Razavi et al., 2006). It has been used for the treatment of human osteosarcoma (Haroun et al., 2009) and skin wound healing (Emami-Razavi et al., 2006) as remedial agent, and manufacturing reservoirs having improved anticancer drug delivery proficiency (Kevadiya et al., 2012). ...
... It also has been applied to the development of health-related products, such as functional foods, cosmetics, and pharmaceuticals (Allo and Murray, 2004;Emami-Razavi et al., 2006). It has been used for the treatment of human osteosarcoma (Haroun et al., 2009) and skin wound healing (Emami-Razavi et al., 2006) as remedial agent, and manufacturing reservoirs having improved anticancer drug delivery proficiency (Kevadiya et al., 2012). For example, bentonite can effectively improve the symptoms of abdominal pain or discomfort in constipation-predominant irritable bowel syndrome (Ducrotté et al., 2005). ...
Article
Kimchi is a popular traditional Korean food and has various beneficial health properties, e.g., it has preventative effects against cancer, obesity, diabetes, and constipation. The characteristics of kimchi, including its texture, flavor, and functionality, are affected by the major and minor ingredients. Bentonite, a clay mineral, is used as a component in functional foods, cosmetics, and pharmaceuticals owing to its physical and chemical characteristics. In this study, different types of cation-substituted forms of bentonite (Na⁺, K⁺ and Mg2 +) were used as kimchi ingredients to analyze their effect on the microbial community during fermentation for 10 days. Amplicon sequencing targeting the bacterial 16S rRNA gene was conducted using the ion torrent PGM system and sequencing data were analyzed with Qiime. At the initial stage, kimchi samples exhibited diverse microflora. Lactic acid bacteria (LAB), such as Weissella, Lactobacillus, and Lactococcus, dominated after 10 days of fermentation. Seven core LAB species, i.e., Leuconostoc gelidum, Leuconostoc gasicomitatum, Weissella koreensis, Leuconostoc citreum, Leuconostoc lactis, Lactobacillus sakei, and Weissella cibaria, showed differences in abundance among samples treated with different types of bentonite.
... Montmorillonite has been combined with different scaffold materials such as chitosan, methyl methacrylate, gelatin, starch, and polycaprolactone for tissue engineering applications [14][15][16]. Montmorillonite nanoclay composite scaffolds have been studied for their applications in bone tissue engineering [15,16], controlled drug delivery [17], and wound healing [18,19]. ...
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In recent years, nanomaterials have attracted significant research interest for applications in biomedicine. Many kinds of engineered nanomaterials, such as lipid nanoparticles, polymeric nanoparticles, porous nanomaterials, silica, and clay nanoparticles, have been investigated for use in drug delivery systems, regenerative medicine, and scaffolds for tissue engineering. Some of the most attractive nanoparticles for biomedical applications are nanoclays. According to their mineralogical composition, approximately 30 different nanoclays exist, and the more commonly used clays are bentonite, halloysite, kaolinite, laponite, and montmorillonite. For millennia, clay minerals have been extensively investigated for use in antidiarrhea solutions, anti-inflammatory agents, blood purification, reducing infections, and healing of stomach ulcers. This widespread use is due to their high porosity, surface properties, large surface area, excellent biocompatibility, the potential for sustained drug release, thermal and chemical stability. We begin this review by discussing the major nanoclay types and their application in biomedicine, focusing on current research areas for halloysite in biomedicine. Finally, recent trends and future directions in HNT research for biomedical application are explored.
... The proliferative phase is involved by the migration and proliferation of keratinocytes and fibroblasts, collagen deposition, angiogenesis, epithelialization, tissue granulation and wound contraction (2). The remodelling phase involves the degradation of excess collagen in the wound by several proteolytic enzymes, leading to the completion of tissue repair (5). Many factors influences the wound healing such as infections, nutrition,drugs and hormones, type and sites of wound, and certain disease conditions (6). ...
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Reinwardtia indica is traditionally used for wound healing. The main aim of this study was to evaluate the wound healing activity of leaves extracts of R. indica using the excision wound model in rats. The leaves of R. indica were collected from Gondrang, Chitwan, Nepal. Leaves were shade dried, extracted by double maceration and subjected to phytochemical screening. Then, the fusion method was used for the formulation of ointment and evaluated. Rats (n=24) were divided into four groups with 6 in each. Excision wound model was used, 2 cm diameter (314 mm 2), 2 mm depth wound was created. The treatment was given daily topically to all groups and the % mean wound contraction rate was calculated on days 4, 8, 12 and 16. The result was analyzed statistically using Graph pad prism version 5. Phytochemical test revealed the presence of alkaloid, flavonoid, tannin, phenol, terpenoid, carbohydrate, etc. All the evaluation parameters showed satisfactory results. The extract of R. indica ointment (2% w/w and 5% w/w) increased the wound contraction rate day by day. The % means wound contraction rate, on day 12, (80% and 88%), and on day 16, (97% and 100%) and statistically significant difference was at p<0.0001. The R. indica extract ointment showed an increased wound contraction rate. So, in further R. indica could be used for commercial production of wound healing ointment.
... The proliferative phase is involved by the migration and proliferation of keratinocytes and fibroblasts, collagen deposition, angiogenesis, epithelialization, tissue granulation and wound contraction (2). The remodelling phase involves the degradation of excess collagen in the wound by several proteolytic enzymes, leading to the completion of tissue repair (5). Many factors influences the wound healing such as infections, nutrition,drugs and hormones, type and sites of wound, and certain disease conditions (6). ...
Article
Full-text available
Reinwardtia indica is traditionally used for wound healing. The main aim of this study was to evaluate the wound healing activity of leaves extracts of R. indica using the excision wound model in rats. The leaves of R. indica were collected from Gondrang, Chitwan, Nepal. Leaves were shade dried, extracted by double maceration and subjected to phytochemical screening. Then, the fusion method was used for the formulation of ointment and evaluated. Rats (n=24) were divided into four groups with 6 in each. Excision wound model was used, 2 cm diameter (314 mm 2), 2 mm depth wound was created. The treatment was given daily topically to all groups and the % mean wound contraction rate was calculated on days 4, 8, 12 and 16. The result was analyzed statistically using Graph pad prism version 5. Phytochemical test revealed the presence of alkaloid, flavonoid, tannin, phenol, terpenoid, carbohydrate, etc. All the evaluation parameters showed satisfactory results. The extract of R. indica ointment (2% w/w and 5% w/w) increased the wound contraction rate day by day. The % means wound contraction rate, on day 12, (80% and 88%), and on day 16, (97% and 100%) and statistically significant difference was at p<0.0001. The R. indica extract ointment showed an increased wound contraction rate. So, in further R. indica could be used for commercial production of wound healing ointment.
... The remodeling phase involves the excess collagen degradation that leads to the completion of the tissue repair. Any agent that has the ability to accelerate these processes is considered as an enhancer of the wound healing process [31]. The result of higher cell migration rate in MCF 7 cell lines of P. africana crude extract indicated that it was a potential wound healing agent. ...
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Endophytic fungi isolated from desert plants are among the less known organisms with potentially valuable applications. The bioactivities of an endophytic fungus isolated from Aloe vera, a plant found in central regions of Asir desert, Saudi Arabia. Based on primary phytochemical screening, an efficient isolate was selected and identified according to the sequence analysis of the internal spacer regions ITS1, ITS4 and the 5.8S region as Preussia africana belonging to the family Sporormiaceae. The crude extract of this fungus was evaluated for its bioactivities. Under static conditions, the crude extract at a concentration of 500 μg/mL had a strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging rate of 87%, whereas a higher concentration (100 μg/mL) had an astounding wound healing effect (42.6% at 48 h) when compared to positive control. Moreover, the crude extract with a concentration of 50 μg/mL was active against almost all cancer cell lines such as HeLa (cervical cancer), Hep G2 (liver cancer), MCF-7 (breast cancer), A549 (lung cancer), LN-229 (glioblastoma), A-431 (skin cancer), and kidney cell line (HEK 293T). The results suggest that the endophytic fungus P. africana from A. vera has wide therapeutic applications against severe disease conditions.
... [51] Skin injury promptly leads to local inflammation and clot formation, causing macrophages and neutrophils infiltration into the wound sites, as a sign of inflammatory phase. [52] In order to study in-depth the mechanism of wound healing, many models including punch models, linear incision models, dead space chambers, polyvinyl sponges and full-thickness punch biopsy models have been frequently used. [53][54][55][56] In the present study, we chose full-thickness punch wounds to research the effect of DHCA on wound healing. ...
Article
Objectives: The aim of this study was to investigate the molecular mechanisms of the efficacy of lignin compound dehydrodiconiferyl alcohol (DHCA) isolated from Silybum marianum (L.) Gaertn in improving wound healing. These findings preliminarily brought to light the promising therapeutic potential of DHCA in skin wound healing. Methods: First, the effect of DHCA on healing in vivo was studied using a full-thickness scalp wound model of mice by topical administration. Histopathological examinations were then conducted by haematoxylin and eosin (H&E), Masson's trichrome staining and the immunofluorescence assay. Second, we further examined the anti-inflammatory mechanism of DHCA in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages by immunofluorescence assay and Western blot analysis. Key findings: DHCA could promote scalp wound healing in mice by enhancing epithelial cell proliferation and collagen formation and reducing inflammatory cells infiltration. Moreover, the NF-κB nuclear translocation was suppressed remarkably by DHCA administration in connective tissue of healing area. DHCA was also shown to inhibit production of nitric oxide (NO) and interleukin (IL)-1β with downregulated inducible nitric oxide synthase (iNOS) expression in LPS-induced RAW 246.7 cells. More importantly, DHCA administration upregulated p-IκBα expression and induced nuclear translocation of NF-κB without affecting its expression. Conclusions: Our study indicated that DHCA exerted anti-inflammatory activity through inactivation of NF-κB pathways in macrophages and subsequently improved wound healing.
... MMT and its products are commonly applied in biomedical fields, e.g., for protection and cleansing of skin, antibacterial activity, adsorption of bacterial pathogens (Escherichia coli and Staphylococcus aureus), immobilization of cell toxins (Meng et al. 2009), and removal of hazardous metals (Khoualdia et al. 2013), also possessing excellent wound healing and blood clotting capabilities (Emami-Razavi et al. 2006) with no side effects. ...
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Bentonite/magnetite powder was synthesized and characterized using laser diffraction, scanning electron microscopy, X-ray diffraction, low-temperature nitrogen adsorption–desorption technique, and magnetization measurements, revealing it to be a ferromagnetic material with mesopores. Hydroxyethyl cellulose was filled with bentonite/magnetite particles by mechanical dispersion to produce hybrid film materials that were studied using various methods. X-ray diffraction analysis showed that the interlayer distance in the clay was increased due to intercalation of polymer molecules. A concentration effect of the filling agent on the tensile properties of the hybrid material was revealed. Infrared (IR) spectrometry indicated an increase in the density of the hydrogen-bonding network. Microbiological tests showed that the HEC/bentonite/magnetite films exhibited antifungal effect against Candida albicans.
... Cosmetic and medicinal uses (Carretero, 2002;Carretero & Pozo, 2009;Carretero et al., 2006;Dário et al., 2014;Elmore, 2003;Emami-Razavi et al., 2006;Gomes et al., 2009;Iborra et al., 2006;López-Galindo et al., 2007;Marks et al., 1995: Nones et al., 2015Williams et al., 2009), An ingredient in toothpaste (see Uddin, 2008 and references therein), A clarifying agent for oils and fats (Inglethorpe et al., 1992), Wastewater treatment ( Barkat et al., 2014;Bourliva et al., 2010;Melichová & Hromada, 2013;Musleh et al., 2014;Syafalni et al., 2013;Tzu et al., 2013;Zhou et al., 2013), An agent to control harmful algal blooms [HABs] ( Sengco & Anderson, 2004), A component of fire retardant gels (Clem & Doehler, 1961;Uddin, 2008), An industrial floor absorbent (Murray, 2005), An anti-caking agent (Murray, 2005), To prevent protein haze in white wine (Blade & Boulton, 1988;Catarino et al., 2008;Pocock and Waters, 2006;Pocock et al., 2011;Waters et al., 2005), Papermaking (Inglethorpe et al., 1992), where it is used in pitch control, i.e. absorption of wood resins that tend to obstruct the machines and to improve the efficiency of the conversion of pulp into paper as well as to improve the quality of the paper, An aid or environmental barrier in nuclear waste management ( Gates et al., 2009;Karnland, 2010;Koch, 2008;Tang & Cui, 2010;Wilson et al., 2011), A component of geosynthetic clay liners [GCL] ( Gates et al., 2009;Trauger, 1994), A coagulant aid in water treatment systems (John & Trollip, 2009), To protect farm and other animals from aflatoxins (Abbès et al., 2010;Abdel-Wahhab et al., 1999;Akande et al., 2006;Bailey et al., 2006;EFSA, 2007;Eckhardt et al., 2014;Eraslan et al., 2004;Huwig et al., 2001;Indresh et al., 2013;Jaynes & Zartman, 2011;Lindemann et al., 1993;Manafi, 2012;Miazzo et al., 2005;Mugerwa et al., 2013;Pappas et al., 2014;Rosa et al., 2001;Thieu et al., 2008;Trckova et al., 2004;Williams et al., 2004), although there are some studies (Fowler et al., 2014) that point to minimal benefits under some circumstances, A food additive to protect humans from the effects of aflatoxins ( Elmore et al., 2014;Phillips, 1999;Robinson et al., 2012;Romoser et al., 2013Wang et al., 2005), To help increase the growth rate of certain hatchery- raised fish ( Eya et al., 2008) or reduce the aflatoxin toxicity in certain fish (Ayyat et al., 2013), As a carrier for pesticides, insecticides, fungicides, growth promoters ( Li et al., 2012), A dust palliative for limestone surfaced secondary roads (Bergeson & Brocks, 1996), To reduce ammonia volatilization losses from poultry litter (Redding, 2013), To reduce the toxicity of poultry litter leachate (Gupta & Gardner, 2005), and As a coating for seeds (Inglethorpe et al., 1992). Inglethorpe et al. (1992) provided a useful mapping between the physico-chemical properties of bentonite and the requirements of various commercial applications. ...
Article
Bentonite, a clay with numerous industrial and consumer applications, is mined and processed in many countries of the world. Its many beneficial uses also create the potential for widespread occupational and consumer exposure. The available studies on toxicity and epidemiology indicate that the principal exposure pathway of concern is inhalation of respirable dust by occupationally exposed cohorts. Bentonite itself is probably not more toxic than any other particulate not otherwise regulated and is not classified as a carcinogen by any regulatory or advisory body, but some bentonite may contain variable amounts of respirable crystalline silica, a recognized human carcinogen. Therefore, prudent management and adherence to occupational exposure limits is appropriate. This review summarizes the literature available on production, applications, exposure, toxicity, and epidemiology of bentonite and identifies data gaps and limitations.
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Background: Cosmeceuticals are commonly used in skincare regimens to maintain healthy skin and improve visible signs of aging. In recent years, South Korean skincare has gained prominence in the global beauty industry by introducing innovative cosmeceutical products and aesthetic trends. Objectives: To describe the global impact of Korean skincare and to review the current research evidence for bioactive ingredients commonly found in Korean cosmeceuticals. Methods: A review of the biomedical literature was conducted using PubMed to identify laboratory, animal, and clinical studies that evaluated the biological properties and potential dermatologic uses of ingredients found in Korean cosmeceuticals. Results: Bioactive ingredients in Korean cosmeceutical products are increasingly undergoing scientific validation and are derived from various sources including animals (eg, bee venom and snail mucin), plants (eg, dragon's blood and tiger grass extract), and biotechnology (eg, synthetic snake venom). Their bioactive components and pharmacologic activities have been shown to provide dermatologic benefits with potential applications for skin rejuvenation, photoprotection, wound healing, and more. Conclusion: Further research studies are warranted to elucidate any biological or therapeutic mechanisms of action of these ingredients, which may translate into clinical practice. With the rising public awareness and interest in Korean cosmeceuticals, patients may seek advice from dermatologists about how to incorporate these bioactive ingredients into their skincare regimens to improve skin health and aesthetics.
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The primary function of the skin is to serve as a protective barrier against the environment. Loss of the integrity of large portions of the skin as a result of injury or illness may lead to major disability or even death. Every year in the United States more than 1.25 million people have burns1 and 6.5 million have chronic skin ulcers caused by pressure, venous stasis, or diabetes mellitus.2 The primary goals of the treatment of wounds are rapid wound closure and a functional and aesthetically satisfactory scar. Recent advances in cellular and molecular biology have greatly expanded our understanding . . .
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Calcium plays an important role in the regulation of cellular differentiation and desquamation of epidermal keratinocytes. In this study, we examined the calcium distribution in reconstructed epidermis in an attempt to understand the physiology of keratinocyte differentiation and desquamation in vitro. Ion capture cytochemistry (the potassium oxalate-pyroantimonate method) was employed to localize ionic calcium in reconstructed epidermis generated under three different culture conditions (in serum-containing medium, serum-free medium, and serum-free medium supplemented with retinoic acid), allowing a comparison of the physiology of incompletely and well-differentiated keratinocytes. The reconstructed epidermis generated in serum-containing medium showed features of incomplete differentiation, and compared with the native skin, a high calcium content within incompletely differentiated cells in the stratum corneum. Use of serum-free medium containing vitamin and lipid supplements led to a marked improvement of the stratum corneum ultrastructure and penetration pathway across the stratum corneum, indicating improved barrier formation of the reconstructed epidermis. In parallel, the calcium distribution pattern was normalized showing the highest levels of calcium in the stratum granulosum and low levels in the inner stratum corneum. Addition of retinoic acid to the serum-free medium resulted in an altered keratinocyte differentiation and re-appearance of large quantities of calcium precipitates in the stratum corneum. Proton probe X-ray microanalysis was applied to investigate the calcium distribution quantitatively in native and reconstructed epidermis generated in serum-free medium, and verified the calcium distribution demonstrated by the precipitation technique. Regardless of the presence or absence of calcium in the stratum corneum, all examined culture systems exhibited insufficient desquamation, which correlates with the finding that stratum corneum chymotryptic enzyme was present predominantly as an inactive precursor. This study demonstrates that improvement of the stratum corneum barrier properties in vitro is concurrent with the normalization of the epidermal calcium gradient, whereas deregulation of terminal differentiation correlates with an accumulation of calcium ions within incompletely differentiated corneocytes.Keywords: confocal laser scanning microscopy, desquamation, ion-capture cytochemistry, proton probe X-ray microanalysis, stratum corneum chymotryptic enzyme, transmission electron microscopy
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This study assessed the effects of cadmium on functional lymphopoietic precursor cells and cell size in both spleen and bone marrow. Splenic plaque-forming cell (S-PFC) precursors were stimulated by a thymus independent immunogen (TNP-LPS) and by a thymus dependent immunogen (TNP-BSA plus dextran sulfate). Bone marrow plaque-forming cell (M-PFC) precursors were stimulated by TNP-LPS plus dextran sulfate. Male C57B1/6J mice received either a single ip injection of 5.9 mg/kg CdCl2, and were sacrificed 3 days later (ip group), or 5 daily sc injections of 3.26 mg/kg CdCl2, and were sacrificed either 2 days later (7 day sc group) or 7 days later (12 day sc group). The ip group showed an increase in spleen cellularity which resulted in an enhanced S-PFC (TNP-LPS) response per spleen and compensated for a depressed S-PFC (TNP-BSA) response per 106 cells cultured. Bone marrow cellularity was not significantly decreased but the M-PFC response was drastically depressed. Similar results were obtained in the 7 day sc group. However, a significant increase in spleen cellularity was not seen, resulting in a noncompensated decrease in S-PFC (TNP-BSA) response. The S-PFC (TNP-LPS) response per 106 cells cultured was increased in this group. Responses were similar to controls in the 12 day sc group, but bone marrow cellularity was decreased. The ip and 7 day sc groups showed substantial cadmium-induced shifts in bone marrow cell size distribution profile to larger diameters. Changes in spleen cell size distribution were not as significant. Partial recovery was evident in the 12 day sc group.This study demonstrated that in vivo exposure to cadmium has a greater effect on the in vitro function of immature B-cells in the bone marrow than on more mature B-cells found in the spleen. Bone marrow toxicity should be considered in future investigations of heavy metal toxicity.
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The biological effects of ore dusts were examined on peritoneal macrophages in vitro and on rat lung in vivo. The methylene blue adsorption of the dust samples, cytotoxicity, and phospholipid and hydroxyproline content of the lung were determined. It was realized that the examined ore samples had cytotoxic effects and from the in vitro results one can get information about the type of damage to be expected in the lung tissue. It is supposed that the examined ore dusts are less dangerous and slower acting than quartz, but they cause progressive fibrosis. The in vivo biochemical experiments do not give information about the type of damage to be expected in lung tissue; and the data on ore, bentonite, and coal do not differ from each other. To determine the typical biochemical changes caused by quartz, we obtain the most valuable information by determination of lung weight and phospholipid, phosphatidylcholine, and hydroxyproline content.