423 research outputs found
ATP-dependent potassium channels are implicated in simvastatin pretreatment-induced inhibition of apoptotic cell death after renal ischemia/reperfusion injury
Background: Simvastatin is a widely used medication in cardiac care. Here we evaluate the role of ATP sensitive potassium (KATP) channels in simvastatin induced renal protection after renal ischemia/reperfusion (I/R) injury. Methods: A total of 81 male Wistar rats, were treated with simvastatin (10 and 20mg/kg/day; gavage, one week). Some groups received glibenclamide (KATP channel inhibitor; 5mg/kg) before ischemia (45min) and reperfusion (24h). Finally the kidneys were processed for histological analysis and measurement of biochemical parameters including tissue malondialdehyde (MDA), blood urea nitrogen (BUN), fractional excretion of sodium (FENa), creatinine clearance rate (CCr) and Bcl2-associated X protein (Bax) expression. Results: IR significantly increased serum Cr (p< 0.01) and BUN levels (p< 0.01), elevated FENa (p<0.01) and tissue MDA (p<0.01), and decreased CCr (p< 0.01) and induced histological damage. Bax pro-apoptotic protein was upregulated in renal tissue after I/R injury and downregulated in simvastatin pretreated group. Simvastatin at doses of 10 and 20mg/kg/day significantly reduced serum Cr and BUN levels (p< 0.05 vs. IR group), tissue MDA contents and FENa (p< 0.05 vs. I/R) and increased CCr (p< 0.05 vs. IR). Renal tissue injury was improved only in simvastatin 20mg/kg/day group (p< 0.05). Glibenclamide significantly abolished protective effects of simvastatin and increased serum Cr and BUN and FENa and decreased CCr (p< 0.05). It also abolished the effects of simvastatin on tissue injury and MDA contents and downregulated the Bax protein after IR injury (p< 0.05). Conclusion: Opening of KATP channels is essential for simvastatin-induced renal protection against I/R injury
Role of morphine preconditioning and nitric oxide following brain ischemia reperfusion injury in mice
Objective(s): Morphine dependence (MD) potently protects heart against ischemia reperfusion (IR) injury through specific signaling mechanisms, which are different from the pathways involved in acute morphine treatment or classical preconditioning. Since opioid receptor density changes post cerebral ischemia strongly correlated with brain histological damage, in the present study, we tried to elucidate the possible role of opioid receptors in IR injury among morphine-dependent mice. Materials and Methods: Accordingly, incremental doses (10 mg/kg/day to 30 mg/kg/day) of morphine sulphate were subcutaneously administered for 5 days before global brain ischemia induction through bilateral common carotid artery occlusion. Animals were received naloxone (5 mg/kg) or L-NAME (20 mg/kg) 30 min after the last morphine dose. Twenty four hr after the ischemia induction, Retention trial of passive avoidance test and western blot analysis were done. histological analysis (TUNEL and NISSL staining) performed 72 hr after ischemia. Results: MD improved post ischemia memory performance (P<0.01) and neuronal survival (P<0.001) and decreased apoptosis (P<0.05) in region I of hippocampus (CA1 region) in mouse. Treatment with naloxone or L-NAME abolished all MD aforementioned effects. Conclusion: Results of the present study suggested that opioid receptors activation in the early hr post ischemia is crucial for MD-induced hippocampus tolerance against IR injury. Opioid receptor-dependent balance of NO production was another key factor in MD-induced protection. Further studies are required to determine the effect of MD on opioid receptor changes after ischemia and its correlation with MD-induced protection. © 2015, Mashhad University of Medical Sciences. All rights reserved
Optimization of energy consumption of ozone generator and plasma generator in decolorization and disinfecting of water system in urban residence
BACKGROUND AND OBJECTIVES: The water field futurology is mostly focused on the water shortage and resulting political-security crises. However, the emphasis of this study is on the water pollution crisis. This study utilizes water decolorization and microbial decontamination as novel and low-risk methods in water and water resources sanitization with the preservation of the municipal environment approach. Modern oxidation methods for pre-treatment or aid-treatment have well-attained their place in the water and wastewater treatment process to reduce microbial and chemical contamination of water. Applying light, plasma, ozone, and Ultraviolet light is one of the modern and eco-friendly methods for water treatment and disinfection with growing usage.METHODS: In this research, various types of ozone and plasma generators, with the approach of energy consumption reduction, were manufactured for simultaneous decolorization and disinfecting of the water. All these devices consist of three main sections; frequency-increasing circuits, voltage-increasing transformers, and a reactor based on electrical discharge in gas. The simulation was performed using Orcad and PSPICE and Comsol softwares. After designing and simulation, a pilot of each of these three sections was made.FINDINGS: Both plasma and ozone reactors, which act as light tubes with a purple color spectrum were made and optimized for water treatment in the form of tubular tubes and flat cell for volume and surface radiation. Microbial testing of 8 water samples in terms of coliform in laboratory was confirmed by the Iran Environmental Organization mpn/100ml.RESULTS: After computer simulation, all three basic sections of an ozone generator device with a power consumption equal to a 30-watt lightbulb were made and optimized. By 5-minute injection of the ozone generated by this device into the water containing methylene blue as the color contamination index and Escherichia coli as the microbial contamination index, 99% of microbial decontamination was achieved, along with decolorization.CONCLUSION: Various types of plasma devices for decolorization and disinfecting water were made in this research. Due to the light-like nature of the plasma treatment and since the tested water sample was volumetric, and above all, due to the turbidity of the tested water sample, 30 minute of plasma treatment had no comparable effect to the ozonation method. Therefore, generating and injecting ozone was still the most effective method for simultaneous decolorization and microbial decontamination. The discoloration of water samples by ozonation with optimized devices was noticeable in the first minute
Giant congenital left ventricular diverticulum associated with infective endocarditis: A diagnosis made by tissue Doppler echocardiography
Left ventricular (LV) diverticulum is a relatively rare condition, and it is important to differentiate it from pseudoaneurysm. The increasing use of noninvasive imaging modalities can help to demonstrate different types of ventricular outpouching structures. We report a case of congenital LV diverticulum that is much larger than the usual size and is diagnosed with tissue Doppler echocardiography and cardiac magnetic resonance imaging. Although a ventricular diverticulum is mostly asymptomatic, in the case of this particular patient, it has become complicated with infective endocarditis. © 2016 Japanese College of Cardiolog
An integrated environmental management approach to industrial site selection by genetic algorithm and fuzzy analytic hierarchy process in geographical information system
Environmental planning and management can have positive effects on development of some land uses including industrial areas that have a major effect on economic, social and environmental conditions. Considering the most important problems associated with modeling, the fundamental methods and functions of site-selection laid inside the geographical information system are not accounted for the multi-purpose experimental programs. The main purpose of this study is to present a systematic pattern for environmental management using genetic algorithm and fuzzy analytic hierarchy process in geographical information system in order to reduce uncertainty. Through fuzzy analytic hierarchy process, the weight of criteria was calculated after extracting the criteria by Delphi technique and identifying all the effective criteria and factors involved in site selection. After preparation of intended layers, each map was prepared in the form of raster layers on geographical information system. Information layers were combined after being valued and finally the map of suitable areas was prepared. Finally, the conformity of all the obtained maps was checked out with field conditions. In this study, the genetic algorithm was used as an optimization method applied for natural selection. It was also attempted to find better solutions among others. The results showed the best site for developing industries
Improvement of tissue survival of skin flaps by 5α-reductase inhibitors: Possible involvement of nitric oxide and inducible nitric oxide synthase
Background: Skin flap grafting is a popular approach for reconstruction of critical skin and underlying soft tissue injuries. In a previous study, we demonstrated the beneficial effects of two 5α-reductase inhibitors, azelaic acid and finasteride, on tissue survival in a rat model of skin flap grafting. In the current study, we investigated the involvement of nitric oxide and inducible nitric oxide synthase (iNOS) in graft survival mediated by these agents. Methods: A number of 42 male rats were randomly allocated into six groups: 1, normal saline topical application; 2, azelaic acid (100 mg/flap); 3, finasteride (1 mg/flap); 4, injection of L-NG-nitroarginine methyl ester (L-NAME) (i.p., 20 mg/kg); 5, L-NAME (20 mg/kg, i.p.) + azelaic acid (100 mg/flap, topical); 6, L-NAME (20 mg/kg, i.p.) + finasteride (1 mg/flap, topical). Tissue survival, level of nitric oxide, and iNOS expression in groups were measured. Results: Our data revealed that azelaic acid and finasteride significantly increased the expression of iNOS protein and nitric oxide (NO) levels in graft tissue (P < 0.05). These increases in iNOS expression and NO level were associated with higher survival of the graft tissue. Conclusion: It appears that alterations of the NO metabolism are implicated in the azelaic acid- and finasteride-mediated survival of the skin flaps. © 2015, Pasteur Institute of Iran. All rights reserved
Atorvastatin treatment softens human red blood cells: An optical tweezers study
Optical tweezers are proven indispensable single-cell micro-manipulation and mechanical phenotyping tools. In this study, we have used optical tweezers for measuring the viscoelastic properties of human red blood cells (RBCs). Comparison of the viscoelastic features of the healthy fresh and atorvastatin treated cells revealed that the drug softens the cells. Using a simple modeling approach, we proposed a molecular model that explains the drug-induced softening of the RBC membrane. Our results suggest that direct interactions between the drug and cytoskeletal components underlie the drug-induced softening of the cells. © 2018 Optical Society of America
The mechanism of preventive effect of captopril on renal ischemia reperfusion injury is independent of ATP dependent potassium channels
Background: Renal ischemia reperfusion (IR) injury has been a major source of concern during the past decades and angiotensin converting enzyme (ACE) inhibitors have been successfully used to prevent this injury. There have been some controversial reports about the involvement of KATP channels in the mechanism of action of ACE inhibitors. In this study, we examined the effect of KATP channel blocker (Glibenclamide) on preventive effect of captopril on renal IR injury. Methods: Male sprauge-dawley rats were pretreated with glibenclamide (1, 5 and 25 mg/kg) and/or captopril (5 mg/kg). They were anesthetized using ketamine (50 mg/kg) and xylazine (10 mg/kg). The left flank was incised and the left renal artery was clamped for 30 minutes. After that, the kidney was reperfused for 2 hours and then the animal was killed. The Right and left kidneys were removed and evaluated for microscopic damage. Results: Captopril reduced renal IR injury while glibenclamide by itself caused no change. Glibenclamide did not change the preventive effect of captopril. Conclusion: It seems that the preventive effect of captopril is not directly mediated by KATP channels and further attention should be paid to other receptor-mediated angiotensin II effects
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