Apostolos Papalois

Università degli studi di Cagliari, Cagliari, Sardinia, Italy

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Publications (187)463.7 Total impact

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    ABSTRACT: Prevention of left ventricular remodeling is an important therapeutic target post-myocardial infarction. Experimentally, treatment with growth hormone (GH) is beneficial, but sustained local administration has not been thoroughly investigated. We studied 58 rats (322 ± 4 g). GH was administered via a biomaterial-scaffold, following in vitro and in vivo evaluation of degradation and drug-release curves. Treatment consisted of intra-myocardial injection of saline or alginate-hydrogel, with or without GH, 10 min after permanent coronary artery ligation. Echocardiographic and histologic remodeling-indices were examined 3 weeks post-ligation, followed by immunohistochemical evaluation of angiogenesis, collagen, macrophages and myofibroblasts. GH-release completed at 3 days and alginate-degradation at ∼7 days. Alginate + GH consistently improved left ventricular end-diastolic and end-systolic diameters, ventricular sphericity, wall tension index and infarct-thickness. Microvascular-density and myofibroblast-count in the infarct and peri-infarct areas were higher after alginate + GH. Macrophage-count and collagen-content did not differ between groups. Early, sustained GH-administration enhances angiogenesis and myofibroblast-activation and ameliorates post-infarction remodeling.
    Growth factors (Chur, Switzerland) 08/2015; DOI:10.3109/08977194.2015.1072527 · 3.09 Impact Factor
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    ABSTRACT: The purpose of the experiment was to compare the effects of nifekalant and amiodarone on the return of spontaneous circulation (ROSC), survival, as well as on the hemodynamic parameters in a swine model of prolonged ventricular fibrillation (VF). After 8 min of untreated VF, bolus doses of epinephrine (adrenaline) and either nifekalant, or amiodarone, or saline (n = 10 per group), were administered after randomization. Cardiopulmonary resuscitation (CPR) was commenced immediately after drug administration and defibrillation was attempted 2 min later. CPR was resumed for another 2 min after each defibrillation attempt and the same dose of adrenaline was given every 4th minute during CPR. Forty-eight hour survival was significantly higher with nifekalant compared to amiodarone (p < 0.001) and saline (p = 0.02), (9/10 vs. 0/10 vs. 3/10, respectively). Systolic aortic pressure, diastolic aortic pressure and coronary perfusion pressure were significantly higher with nifekalant during CPR and immediate post-resuscitation period (p < 0.05). The animals in the amiodarone group had a slower heart rate at the 1st and 45th min post-ROSC (p < 0.001 and p = 0.006, respectively). The number of electric shocks required for terminating VF, time to ROSC and adrenaline dose were significantly higher with amiodarone compared to nifekalant (p < 0.001). Nifekalant showed a more favorable hemodynamic profile and improved survival compared to amiodarone and saline in this swine model.
    Cardiovascular Drugs and Therapy 07/2015; DOI:10.1007/s10557-015-6604-7 · 2.95 Impact Factor
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    ABSTRACT: Hemorrhage is a frequent event in hospital and prehospital settings. The aim of the present study was to investigate whether centhaquin improves 24-h survival and reduces the total volume of required fluids in an established model of swine hemorrhagic shock. Twenty-five pigs were instrumented and subjected to hemorrhagic shock. The animals were randomly allocated in two experimental groups, the control (vehicle) (n = 10) and the centhaquin groups (0.015 mg/kg, n = 10); all animals received lactated Ringer solution in the resuscitation phase until their mean arterial pressure reached 90% of the baseline. A sham group (n = 5) was added a posteriori to mimic the hemodynamic profile of the centhaquin group. A statistically significant difference was observed in the time required for the three groups to reach their target mean aortic pressure, 36.88 ± 3.26 min for the control group versus 9.40 ± 1.01 min for the sham group and 7.10 ± 0.97 min for the centhaquin group (P < 0.001). The total amount of fluids in the control and the sham groups was significantly higher when compared with that of the centhaquin-treated animals (P < 0.001). All 10 animals in the centhaquin group survived for 24 h, whereas only three animals survived in the control group and one animal in the sham group (P = 0.002). Centhaquin 0.015 mg/kg administered in the fluid resuscitation phase resulted in lower volume of fluids and better survival compared with control and sham-operated animals. Copyright © 2015 Elsevier Inc. All rights reserved.
    Journal of Surgical Research 06/2015; DOI:10.1016/j.jss.2015.06.056 · 2.12 Impact Factor
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    ABSTRACT: Although high quality cardiopulmonary resuscitation is one of the most significant factors related to favourable outcome, its quality depends on many components, such as airway management, compression depth and chest recoil, hands-off time, and early defibrillation. The most common way of controlling the resuscitation efforts is monitoring of end-tidal carbon dioxide. The International Liaison Committee on Resuscitation suggests this method both for in-hospital and out-of-hospital cardiac arrest. However, despite the abundant human and animal studies supporting the usefulness of end-tidal carbon dioxide, its optimal values during cardiopulmonary resuscitation remain controversial. In this review, the advantages and effectiveness of end-tidal carbon dioxide during cardiopulmonary resuscitation are discussed and specific target values are suggested based on the available literature. Copyright © 2015 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.
    Heart, Lung and Circulation 06/2015; DOI:10.1016/j.hlc.2015.05.013 · 1.17 Impact Factor
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    ABSTRACT: The contribution of extra virgin olive oil (EVOO) macro- and micro-constituents in heart oxidative and inflammatory status in a hypercholesterolemic rat model was evaluated. Fatty acid profile as well as α-tocopherol, sterol, and squalene content was identified directly in rat hearts to distinguish the effect of individual components or to enlighten the potential synergisms. Oils and oil-products with discernible lipid and polar phenolic content were used. Wistar rats were fed a high-cholesterol diet solely, or supplemented with one of the following oils, i.e., EVOO, sunflower oil (SO), and high-oleic sunflower oil (HOSO) or oil-products, i.e., phenolics-deprived EVOO [EVOO(-)], SO enriched with the EVOO phenolics [SO(+)], and HOSO enriched with the EVOO phenolics [HOSO(+)]. Dietary treatment lasted 9 weeks; at the end of the intervention blood and heart samples were collected. High-cholesterol-diet-induced dyslipidemia was shown by increase in serum total cholesterol, low-density lipoprotein cholesterol, and triacylglycerols. Dyslipidemia resulted in increased malondialdehyde (MDA) and tumor necrosis factor-α (TNF-α) levels, while glutathione and interleukin 6 levels remained unaffected in all intervention groups. Augmentation observed in MDA and TNF-α was attenuated in EVOO, SO(+), and HOSO(+) groups. Heart squalene and cholesterol content remained unaffected among all groups studied. Heart α-tocopherol was determined by oil α-tocopherol content. Variations were observed for heart β-sitosterol, while heterogeneity was reported with respect to heart fatty acid profile in all intervention groups. Overall, we suggest that the EVOO-polar phenolic compounds decreased MDA and TNF-α in hearts of cholesterol-fed rats.
    European Journal of Nutrition 06/2015; DOI:10.1007/s00394-015-0947-5 · 3.84 Impact Factor
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    ABSTRACT: Tissue regeneration and wound healing are severely impaired in diabetes and are associated with poor circulation and dysfunctional blood vessels. Angiotensin II inhibitors are anti-hypertensive drugs used in clinical practice to regulate blood pressure and could affect tissue remodeling. We hypothesize that blocking angiotensin II, using Losartan, could facilitate tissue regeneration in diabetic mice. To this end, we established an experimental model of wound healing in streptozotocin-induced diabetic mice. Our data demonstrated that Losartan accelerates wound repair and normalizes wound stromal responses, having a beneficial role in diabetic wounds. Our findings highlight a potential therapeutic use of Losartan in improving wound repair in diabetic conditions.
    Frontiers in Physiology 06/2015; 6. DOI:10.3389/fphys.2015.00170 · 3.50 Impact Factor
  • 06/2015; DOI:10.5152/etd.2015.0005
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    ABSTRACT: Exogenous intake of glycotoxins present in western diet accelerates the accumulation of advanced glycation end products (AGEs) in multiple organs leading to potential tissue damage. Advanced ageing and diabetic conditions have been associated with AGEs deposition in multiple eye compartments including Bruch's membrane, optic nerve, lens and cornea. However, the impact of dietary AGEs in ocular physiology has not been extensively studied. The present study investigates the direct effects of a high AGE content diet in the ocular tissues of normal rats of different age. Two groups of baby (4 weeks of age) and adult (12 weeks of age) female Wistar rats (n = 73) were allocated to high- or low-AGE diet for 3 months. Upon completion of experimental protocol, somatometric, hormonal and biochemical parameters were evaluated in all groups. Circulating and tissue AGE levels were estimated along with their signaling receptor (receptor for AGEs, RAGE) and vascular endothelial growth factor A (VEGF-A) expression in ocular tissues of the different subgroups. High AGE intake was associated with elevated serum AGEs (p = 0.0001), fructosamine (p = 0.0004) and CRP levels (p = 0.0001) compared to low AGE. High peripheral AGE levels were positively correlated with significant increased tissue immunoreactivity of AGEs and RAGE in retinal and uveal tissues as well as retinal VEGF-A expression. Up-regulation of RAGE and VEGF-A expression was observed in the ocular tissue of both baby and adult animals fed with high-AGE diet. Co-localization of AGEs and RAGE staining was observed mainly in the inner retinal layers and the retinal pigment epithelium (RPE) of all groups. VEGF-A expression was elevated in the RPE, the inner nuclear layer and the retinal ganglion cell layer of the animals exposed to high-AGE diet. In conclusion, dietary AGEs intake affects the physiology of ocular tissues by up-regulating RAGE and VEGF-A expression contributing to enhanced inflammatory responses and pathologic neovascularization in normal organisms independent of ageing. Copyright © 2015. Published by Elsevier Ltd.
    Experimental Eye Research 05/2015; 137. DOI:10.1016/j.exer.2015.05.017 · 3.02 Impact Factor
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    ABSTRACT: To analyze the effects on the kidney of hypoxia-reoxygenation in an experimental model of normocapnic asphyxia. To this end, 40 newborn Landrace/Large-White piglets aged 1-4 d were studied in this work. Hypoxia was induced by decreasing the inspired fiO2 to 0.06-0.08. Animals were resuscitated with different fiO2 and subdivided into 4 groups: group 1, 2, 3 and 4 received 18%, 21%, 40% and 100% O2 respectively. Macroscopic examination was carried out to evidence possible pathological features. Tissue sample were obtained from both kidneys. Four or five micron paraffin sections were stained with H-E and PAS stain and examined under an optical microscope. Pathological changes, mainly affecting tubular cells, were observed in the vast majority of kidneys of asphyxiated piglets. The most frequent tubular changes were: tubular casts (95%), tubular dilatation (87.5%), tubular vacuolization (70%), tubular eosinophilia (52.5%), sloughing (50%), fragmentation of the brush border (50%), oedema (32.5%), apoptosis (15%) and glomerular changes (meningeal cell proliferation, capsular adhesion between the flocculus and Bowman's capsule, glomerulosclerosis and fibrous or cellular crescents associated with collapse of the glomerular tuft). Statistical analysis was carried out on changes observed when the animals were allocated in the 4 groups (χ(2)-test 0.05). The statistical analysis showed no evidence of differences regarding kidney lesions among the animals groups. Our data show that renal pathology in newborn piglets is characterized by interindividual variability to hypoxia and is not associated with oxygen concentration.
    05/2015; 4(2):313-8. DOI:10.5527/wjn.v4.i2.313
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    ABSTRACT: Pancreatic carcinoma is one of the commonest malignant diseases today and the majority of patients are suitable for palliative treatment only. Radiofrequency ablation (RFA) has been used extensively for the treatment of solid organ tumors but little is known on the efficacy and safety of pancreatic ablation. To further investigate the safety of pancreatic RFA, 18 pigs had RFA of the pancreas, close to superior mesenteric vein and duodenum. Group A (nine animals) was protected with peripancreatic cool perfusion and Group B (nine animals) with portal vein (PV) intravenous injection of cool saline. Biochemical and histological evidence suggested lateral thermal injury of the duodenal wall and superior mesenteric vein and acute pancreatitis in most animals. However, clinically and at autopsy, Group B animals fared much better. PV thrombosis, hepatic abscess, duodenal perforation, ascites, and extensive pancreatic necrosis were observed in Group A but not in Group B. The present study suggests that PV cool saline perfusion can prevent major complications caused by pancreatic RFA and may be used in combination with other protective techniques in the clinical setting to reduce RFA-associated morbidity.
    The American surgeon 05/2015; 81(5). · 0.92 Impact Factor
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    ABSTRACT: Tumour necrosis factor α (TNF-α) and interleukin 1β (IL-1β) are important mediators of intracerebral haemorrhage inflammatory response. Lazaroids, established antioxidants and neuroprotectants, have been studied in several brain pathologies. The present study was designed to investigate: a) TNF-α and IL-1β changes, in neurons and b) U-74389G effects, 4 and 24h after haematoma induction in a porcine model of intracerebral haemorrhage. In twenty male landrace pigs (swines) aged 135-150 days old, autologous whole blood was injected around the right basal ganglia territory; in ten of the pigs the lazaroid compound U-74389G was administered. Brain TNF-α and IL-1β immunopositive neurons were determined by immunoarray techniques at 4 and 24h timepoints. After the haematoma induction the number of TNF-α immunopositive neurons ipsilateral to the haematoma was significantly higher compared to the contralateral site at 4h (p<0.0005), while U-74389G significantly reduced the number of TNF-α immunopositive neurons, ipsilateral to the haematoma, at 4h (p=0.002); at 24h, TNF-α immunopositive neurons were found significantly higher at both contralateral and ipsilateral site (p<0.0005), The number of IL-1β immunopositive neurons at 4h after the hematoma induction was significantly higher ipsilateral to the haematoma site (p<0.0005). U-74389G had no statistical significant effect. TNF-α and IL-1β, increase in neurons, 4h after the haematoma induction, ipsilateral to the haematoma site. The administration of the antioxidant compound U-74389G, results in early (at 4h), decrease of TNF-α immunopositive neurons but shows no statistical significant effect to IL-1β immunopossitive neurons. Copyright © 2015. Published by Elsevier B.V.
    Brain research 04/2015; 1615. DOI:10.1016/j.brainres.2015.04.034 · 2.83 Impact Factor
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    ABSTRACT: Circulating tumor cells (CTCs) provide a non-invasive accessible source of tumor material from patients with cancer. The cellular heterogeneity within CTC populations is of great clinical importance regarding the increasing number of adjuvant treatment options for patients with metastatic carcinomas, in order to eliminate residual disease. Moreover, the molecular profiling of these rare cells might lead to insight on disease progression and therapeutic strategies than simple CTCs counting. In the present study we investigated the feasibility to detect KRAS, BRAF, CD133 and Plastin3 (PLS3) mutations in an enriched CTCs cell suspension from patients with colorectal cancer, with the hypothesis that these genes` mutations are of great importance regarding the generation of CTCs subpopulations. Subsequently, we compared CTCs mutational status with that of the corresponding primary tumor, in order to access the possibility of tumor cells characterization without biopsy. CTCs were detected and isolated from blood drawn from 52 colorectal cancer (CRC) patients using a quantum-dot-labelled magnetic immunoassay method. Mutations were detected by PCR-RFLP or allele-specific PCR and confirmed by direct sequencing. In 52 patients, discordance between primary tumor and CTCs was 5.77% for KRAS, 3.85% for BRAF, 11.54% for CD133 rs3130, 7.69% for CD133 rs2286455 and 11.54% for PLS3 rs6643869 mutations. Our results support that DNA mutational analysis of CTCs may enable non-invasive, specific biomarker diagnostics and expand the scope of personalized medicine for cancer patients.
    PLoS ONE 04/2015; 10(4):e0123902. DOI:10.1371/journal.pone.0123902 · 3.23 Impact Factor
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    ABSTRACT: The use of herbal therapy in inflammatory bowel disease (IBD) is increasing worldwide. The aim of this study was to review the literature on the efficacy of herbal therapy in IBD patients. Studies on herbal therapy for IBD published in Medline and Embase were reviewed, and response to treatment and remission rates were recorded. Although the number of the relevant clinical studies is relatively small, it can be assumed that the efficacy of herbal therapies in IBD is promising. The most important clinical trials conducted so far refer to the use of mastic gum, tormentil extracts, wormwood herb, aloe vera, triticum aestivum, germinated barley foodstuff, and boswellia serrata. In ulcerative colitis, aloe vera gel, triticum aestivum, andrographis paniculata extract and topical Xilei-san were superior to placebo in inducing remission or clinical response, and curcumin was superior to placebo in maintaining remission; boswellia serrata gum resin and plantago ovata seeds were as effective as mesalazine, whereas oenothera biennis had similar relapse rates as ω-3 fatty acids in the treatment of ulcerative colitis. In Crohn's disease, mastic gum, Artemisia absinthium, and Tripterygium wilfordii were superior to placebo in inducing remission and preventing clinical postoperative recurrence, respectively. Herbal therapies exert their therapeutic benefit by different mechanisms including immune regulation, antioxidant activity, inhibition of leukotriene B4 and nuclear factor-kappa B, and antiplatelet activity. Large, double-blind clinical studies assessing the most commonly used natural substances should urgently be conducted.
    Annals of Gastroenterology 04/2015; 28(2):210-220.
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    ABSTRACT: Sympathetic activation during acute myocardial infarction (MI) is an important arrhythmogenic mechanism, but the role of central autonomic inputs and their modulating factors remain unclear. Using the in vivo rat-model, we examined the effects of clonidine, a centrally acting sympatholytic agent, in the presence or absence of myocardial endothelin-B (ETB) receptors. We studied wild-type (n = 20) and ETB-deficient rats (n = 20) after permanent coronary ligation, with or without pretreatment with clonidine. Cardiac rhythm was continuously recorded for 24 h by implantable telemetry devices, coupled by the assessment of autonomic and heart failure indices. Sympathetic activation and arrhythmogenesis were more prominent in ETB-deficient rats during the early phase post-ligation. Clonidine improved these outcomes throughout the observation period in ETB-deficient rats, but only during the delayed phase in wild-type rats. However, this benefit was counterbalanced by atrioventricular conduction abnormalities and by higher incidence of heart failure, the latter particularly evident in ETB-deficient rats. Myocardial ETB-receptors attenuate the arrhythmogenic effects of central sympathetic activation during acute MI. ETB-receptor deficiency potentiates the sympatholytic effects of clonidine and aggravates heart failure. The interaction between endothelin and sympathetic responses during myocardial ischemia/infarction and its impact on arrhythmogenesis and left ventricular dysfunction merits further investigation.
    02/2015; http://journal.frontiersin.org/article/10.3389/fcvm.2015.00006/full. DOI:10.3389/fcvm.2015.00006
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    ABSTRACT: The potential of lazaroid U-74389G in attenuating injury after ischemia and reperfusion has been reported in various organs. The present study focuses specifically on the pancreas and aims to examine any effects of U-74389G in a swine model of pancreatic ischemia and reperfusion, encompassing ischemic preconditioning. Twelve pigs, weighing 28-35 kg, were randomized into two experimental groups. Group A (control group, n=6): Two periods of ischemic preconditioning (5 min each) separated by a 5-min rest interval; then ischemia time 30 min and reperfusion for 120 min. Group B (n=6): the same as above, with U-74389G intravenous injection in the inferior vena cava immediately prior to the initiation of reperfusion. Blood sampling and pancreatic biopsies were conducted at 0, 30, 60, 90 and 120 min after reperfusion. Repeated-measures ANOVA was undertaken to evaluate differences between the two study groups. No statistically significant differences were noted concerning the histopathological parameters in the control and therapy groups (P=0.563 for edema, P=0.241 for hemorrhage, P=0.256 for leukocyte infiltration, P=0.231 for acinar necrosis and P=0.438 for vacuolization). In accordance with the above, serum metabolic data (glucose, creatinine, urea, total and direct bilirubin, total calcium, amylase, lipase, SGOT/AST, SGPT/ALT, ALP, GGT, LDH, CRP, insulin) were not significantly different between the two groups; similarly, tumor necrosis factor-α values (P=0.705) and tissue malondialdehyde levels (P=0.628) did not differ between the two groups. This swine model of pancreatic ischemia and reperfusion, encompassing preconditioning, indicates that U-74389G lazaroid does not seem to exert protective effects from pancreatic damage.
    JOP: Journal of the pancreas 01/2015; 16(2):176-84.
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    John K. Triantafillidis · Costas Vagianos · Apostolos E. Papalois
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    ABSTRACT: Enteral nutrition (EN) is considered to be of great importance in patients with inflammatory bowel disease (IBD) and nutritional problems. This comprehensive review is aiming to provide the reader with an update on the role of EN in IBD patients. EN can reduce Crohn’s disease (CD) activity and maintain remission in both adults and children. Nutritional support using liquid formulas should be considered for CD patients and in serious cases of ulcerative colitis (UC), especially for those who may require prolonged cycles of corticosteroids. Given that the ultimate goal in the treatment of CD is mucosal healing, this advantage of EN over corticosteroid treatment is valuable in therapeutic decision-making. EN is indicated in active CD, in cases of steroid intolerance, in patient’s refusal of steroids, in combination with steroids in undernourished individuals, and in patients with an inflammatory stenosis of the small intestine. No differences between the efficiency of elemental diets and nonelemental formulas have been noticed. EN must be the first choice compared to TPN. EN has a restricted value in the treatment of patients with large bowel CD. In conclusion, it seems important not to underestimate the role of nutrition as supportive care in patients with IBD.
    01/2015; 2015:1-12. DOI:10.1155/2015/197167
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    ABSTRACT: Ischemia-reperfusion injury caused by severe hemorrhagic shock and subsequent resuscitation leads to deterioration of hepatic homeostasis and possibly to liver failure. The present study focuses on determining whether there is a different biological response to hemorrhagic shock by different sources of hemorrhage, hepatic hemorrhage (HH) versus peripheral hemorrhage. Twenty-one male swine (Sus scrofa domesticus) were randomly allocated in three groups as follows: sham group (S, n = 5), central venous hemorrhage group, (CVH) (n = 8), and HH group (n = 8). Hepatectomy of the left liver lobe was carried out in groups CVH and HH, and the animals were subjected to controlled bleeding from the internal jugular vein and the traumatic liver surface, respectively. After 10 min of hemorrhage, shock was maintained for 30 min at mean arterial pressure levels of 30 mm Hg-40 mm Hg and resuscitation was initiated with crystalloids and colloids. Hemodynamic parameters and fluid balance were monitored throughout the 6 h of total duration of the experiment. Blood samples were collected at 0-, 40-, and 360-min time points for transaminases, albumin, and interleukin-6 measurement. Hepatic tissue was harvested at the end of the experiment for oxidative marker and proliferation analysis. Although blood loss was comparable between the two groups, the amount of fluids needed for resuscitation was higher for the HH group. Inflammatory response, measured by interleukin-6, was found higher in HH group. Oxidative stress markers did not reveal statistically significant difference between the two groups. Liver hemorrhage decreased hepatocellular proliferation measured by proliferating cell nuclear antigen. Our study provides evidence that HH entails worse consequences for the hepatocytes than systemic hemorrhage. Higher needs for resuscitation fluids, decreased proliferation, and augmented inflammatory response when HH takes place are findings with possible clinical importance in liver surgery and trauma. Copyright © 2015 Elsevier Inc. All rights reserved.
    Journal of Surgical Research 12/2014; 195(1). DOI:10.1016/j.jss.2014.12.046 · 2.12 Impact Factor
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    ABSTRACT: The effects of changes in left ventricular (LV) afterload on diastolic function of acutely ischemic and reperfused myocardium have not been studied in depth. We examined 1) the consequences of increasing the LV afterload on LV diastolic function during acute ischemia and reperfusion, 2) whether the myocardial response to afterload elevation is stable throughout a 2-h reperfusion period, and 3) the role of LV wall synchrony on the development of afterload-induced diastolic dysfunction. We instrumented 12 anesthetized, open chest pigs with Millar pressure catheters and piezoelectric crystals before ligating the mid left anterior descending coronary artery for 1 h, followed by reperfusion for 2 h. Six of the animals survived throughout the 2 hours of reperfusion and their data were used for comparisons across the different experimental phases. LV afterload was increased by inflating an intraaortic balloon. Data were recorded at baseline and after 20 min of coronary occlusion, and 30 and 90 min of myocardial reperfusion. The increased afterload for 2 minutes lengthened the isovolumic relaxation during ischemia, and during early and late reperfusion but had no significant effect on isovolumic relaxation before coronary artery occlusion. Increasing the afterload aggravated LV diastolic dyssynchrony during coronary artery occlusion, but not during reperfusion. The afterload-induced prolongation of isovolumic relaxation was positively correlated with afterload-induced diastolic dyssynchrony. These observations indicate that, during myocardial ischemia and throughout reperfusion, LV diastolic function is afterload-dependent. Afterload-induced diastolic dyssynchrony might be an underlying mechanism of diastolic dysfunction during acute ischemia.This article is protected by copyright. All rights reserved
    Experimental physiology 12/2014; 100(3). DOI:10.1113/expphysiol.2014.082131 · 2.87 Impact Factor
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    ABSTRACT: Background: The readmission of molecular oxygen into an ischemic tissue promotes the oxidation of resuscitated tissue with certain pathophysiologic mechanisms. Materials and methods: Twenty four pigs (male or female) were randomized in this study. The animals were allocated to four groups with an equal number (n = 6) in each group: 1) control group-ischemia for 30 min and reperfusion for 60 min. 2) control group-ischemia for 30 min and reperfusion for 120 min. 3) ischemia for 30 min and immediate iv injection of lazaroid U-74389G and reperfusion for 60 min. 4) ischemia for 30 min and immediate iv injection of lazaroid U-74389G and reperfusion for 120 min. Results: We investigated further the role of an antioxidant molecule such as U-74389G and we concluded that there is statistically significant relation in MDA (malondialdeyde), TNF -α (tumor necrosis factor-α) measurement in tissue, while the histological score in the groups that the lazaroid was administered was improved. Conclusions: In many emergency clinical situations, such as reperfusion of the intestine, the role of U-74389G can be protective. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
    International Journal of Surgery (London, England) 11/2014; 13. DOI:10.1016/j.ijsu.2014.11.030 · 1.65 Impact Factor
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    ABSTRACT: Background: Cardiopulmonary resuscitation (CPR) in patients with severe sepsis and septic shock is challenging and usually unsuccessful. The aim of the present study is to describe our swine model of cardiac arrest and resuscitation in severe sepsis and septic shock. Methods: In this prospective, randomized animal study, ten female healthy Landrace-Large White pigs with an average weight of 20+/-1 kg (aged 19-21 weeks) were the study subjects. Septicemia was induced by an intravenous infusion of a bolus of 20 ml bacterial suspension in two min, followed by a continuous infusion during the rest of the experiment. After septic shock was confirmed, the animals were left untreated until cardiac arrest occurred. Results: All animals developed pulseless electrical activity between the fifth and sixth hour of septicemia, while five of ten (50%) animals were successfully resuscitated. Coronary perfusion pressure was statistically significantly different between surviving and non-surviving animals. We found a statistically significant correlation between mean arterial pressure and unsuccessful resuscitation (p=0.046), while there was no difference in end-tidal carbon dioxide (23.05+/-1.73 vs.23.56+/-1.70; p=0.735) between animals with return of spontaneous circulation and non-surviving animals. During the 45-min post-resuscitation monitoring, we noted a significant decrease in hemodynamics parameters, although oxygenation indices and lactate clearance were constantly increased (p=0.001). Conclusions: This successful basic swine model was for the first time developed and may prove extremely useful in future studies on the peri-arrest period in severe sepsis and septic shock.
    Shock (Augusta, Ga.) 11/2014; 43(3). DOI:10.1097/SHK.0000000000000285 · 2.73 Impact Factor

Publication Stats

1k Citations
463.70 Total Impact Points

Institutions

  • 2013–2015
    • Università degli studi di Cagliari
      Cagliari, Sardinia, Italy
  • 2009–2015
    • University of Ioannina
      • Division of Cardiology
      Yannina, Epirus, Greece
  • 2014
    • University of Glasgow
      • College of Medical, Veterinary and Life Sciences
      Glasgow, Scotland, United Kingdom
  • 2012–2014
    • Laiko Hospital
      Athínai, Attica, Greece
    • University of Patras
      Rhion, West Greece, Greece
  • 2006–2014
    • Elpen Pharmaceuticals Co. Inc.
      Athínai, Attica, Greece
    • Forest Research Institute of Athens
      Athínai, Attica, Greece
  • 2009–2012
    • Attikon University Hospital
      • Department of Cardiology
      Athínai, Attica, Greece
  • 2004–2012
    • Harokopion University of Athens
      Athínai, Attica, Greece
    • Alexandra Regional General Hospital
      Athínai, Attica, Greece
  • 2011
    • Hospital for the Heart
      San Paulo, São Paulo, Brazil
  • 2007–2011
    • Red Cross Hospital, Athens
      Athínai, Attica, Greece
  • 2000–2010
    • ΓΕΝΙΚΟ ΝΟΣΟΚΟΜΕΙΟ ΑΘΗΝΩΝ "Γ. ΓΕΝΝΗΜΑΤΑΣ"
      Athínai, Attica, Greece
  • 2008
    • Democritus University of Thrace
      • Laboratory of Pharmacology
      Komotina, East Macedonia and Thrace, Greece
  • 2003–2006
    • National and Kapodistrian University of Athens
      Athínai, Attica, Greece
  • 2000–2001
    • Onassis Cardiac Surgery Center
      • Department of Cardiology
      Kallithea, Attica, Greece