1,630 research outputs found
Lipid peroxidation, brush border, and neutrophil enzyme activity after small bowel preservation: A comparison of preservation solutions
Total Thiols and MDA Levels in Patients with Acute Myocardial Infarction Before and After Reperfusion Therapy
Background: Reactive oxygen species have been implicated in the pathogenesis of ischemic and reperfusion injury. In the current work we have measured malondialdehyde (MDA), total thiols, total CK, CK-MB and AST in ECG proven acute myocardial infarction (AMI) patients immediately after admission and 24 hours after administration of thrombolytic agent streptokinase, and in healthy controls. Methods: Blood samples from 44 AMI patients and 25 age and sex matched healthy controls were obtained and analyzed for MDA, total thiols using spectrophotometric methods and cardiac enzymes CK, CK-MB and AST using automated analyzer. Results: We have found significant increase in MDA, CPK, CK-MB, AST (p< 0.001) and significant decrease in total thiols (p<0.001) in AMI patients after thrombolytic therapy compared to values at admission, and healthy controls. MDA correlated negatively with total thiols (r = - 0.333, p<0.05) and positively with CK-MB (r = 0.491, p<0.01) in AMI patients after thrombolytic therapy. Conclusions: Reperfusion following thrombolytic therapy increases reactive oxygen species with concomitant decrease in antioxidant total thiols
Влияние криоконсервированного экстракта плаценты на интенсивность ПОЛ и содержание гидроперекисей липидов в тканях крыс в норме и после общего острого охлаждения
Изучали влияние криоконсервированного экстракта плаценты на интенсивность перекисного окисления липидов (ПОЛ) и содержание гидроперекисей липидов в сыворотке крови и гомогенатах печени, сердца крыс линии Вистар в нормальных
условиях и после общего острого охлаждения. Было установлено, что общее острое охлаждение животных увеличивает интенсивность ПОЛ, а также содержание гидроперекисей липидов в тканях печени, сердца и сыворотке крови крыс. Введение
криоконсервированного экстракта плаценты предотвращает активацию ПОЛ во всех изученных тканях подопытных животных, что свидетельствует, по нашему мнению, об активации биохимических механизмов адаптации, компенсирующих нарушения,
вызванных действием холода.Effect of cryopreserved placenta extract on lipid peroxidation (LPO) intensity and lipid hydroperoxide content in Wistar line rats’ blood serum and liver, heart homogenates under normal conditions and following general acute cooling was studied. General acute
cooling of animals was found to increase the LPO intensity as well as lipid hydroperoxide content in rat liver, heart tissues and blood serum. Introduction of cryopreserved placenta extract prevents LPO activation in all studied tissues of experimental animals and we
believe this testifies to the activation of biochemical adaptation mechanisms, compensating cold-caused disorders.Вивчали вплив кріоконсервованого екстракту плаценти на інтенсивність перекисного окислення ліпідів і вміст гідроперекисів ліпідів у сироватці крові та гомогенатах печінки, серця щурів лінії Вістар у нормальних умовах і після загального гострого
охолодження. Було встановлено, що загальне гостре охолодження тварин збільшує інтенсивність ПОЛ, а також вміст гідроперекисів ліпідів у тканинах печінки, серця й сироватці крові щурів. Введення кріоконсервованого екстракту плаценти
запобігає активацію ПОЛ у всіх вивчених тканинах піддослідних тварин, що свідчить, за нашою думкою, про активацію біохімічних механізмів адаптації, які компенсують порушення, викликані дією холоду
The implications of nitrogen on the fermentative growth extension of Saccharomyces cerevisiae by isoproturon
The peptone is used to provide nitrogen to Saccharomyces cerevisiae, which is an essential element for growth.
In nature and in industrial musts, essential nutrients for yeast growth are available in complex and variable flux.
Some of these compounds are herbicides, where some specific microorganisms are capable to mineralize or
degrade into more basic and less harmful compounds to the environmental. The isoproturon (IPU), a phenylurea
used as an herbicide, is a compound very difficult to degrade in soils and aquifers, reaching levels considered
toxic by European legislation, contributing to both surface and ground water pollution, and it may be also
involved in the triggering of serious illnesses. So, it’s urgent to discover biological models to contribute to
degrade or eliminate phenylureas in situations of accidental or systematic contamination.
The main target of this study was to evaluate the influence of nitrogen to extend the fermentative phase of S.
cerevisiae by IPU, using the wild-type strain UE-ME3 deposited in the collection of Enology Laboratory of
University of Évora, Portugal.
Cells at mid-exponential phase were inoculated in presence of 100μM IPU in YEPD or YED medium and
incubated during 72 h with orbital stirring, at 28 ºC. Samples from each treatment were used to obtain OD, cfu,
dry weight and to prepare post-12000 g supernatant for determination of protein [1], glutathione (GSH,GSSG)
[2] and malondialdehyde (MDA) [3] contents, and cell capacity to scavenge free radicals by the 2,2-diphenyl-1-
picryl-hidrazil (DPPH) [4] method, as well as, enzyme activities catalase T (CAT T) [5], glutathione reductase
(GR) [6], glutathione peroxidase (GPx) [7], glucose-6-phosphate dehydrogenase (G6PD) [8], alcohol
dehydrogenase (ADH) [9], malate dehydrogenase (MDH2) [10] and lactate dehydrogenase (LDH) [11] by
fluorescence and spectrophotometry. The post-12000 g pellet was also used for protein content and enzyme
activity catalase A (CAT A) determination.
The results show that yeast grown in presence of IPU in peptone starvation conditions (YED-IPU) exhibit at 72 h
a differential growth profile, with cfu, OD, dry weight and level of protein lower than cells grown in YEPD-IPU.
The same type of response was detected in terms of antioxidant power estimated by the GSH/GSSG ratio and
ability to scavenge free radicals detected by DPPH, as well as the levels of enzyme activities CAT T, CAT A,
GR and G6PD which appears much lower in yeast cells grown in YED-IPU medium. On the other hand, cells
exposed to IPU in YEPD medium exhibited fermentative activities, ADH and LDH, higher than those detected in
cells exposed to phenylurea in the restrictive nitrogen medium, YED-IPU. This set of results suggests that yeast
grown in rich medium, YEPD-IPU, remained more fermentative than those grew up in restrictive YED-IPU
medium. This interpretation maybe confirmed by higher levels of glutathione and MDA contents, as well as
enzyme activities GPx and MDH2 detected in S. cerevisiae exposed to YEPD-IPU which started early the
respiratory-fermentative transition. So, S. cerevisiae grown in the nitrogen starvation conditions may more easily
recognize isoproturon as substrate and expand its fermentative phase
A simple method to assess the oxidative susceptibility of low density lipoproteins
BACKGROUND: Oxidative modification of low density lipoproteins (LDL) is recognized as one of the major processes involved in atherogenesis. The in vitro standardized measurement of LDL oxidative susceptibility could thus be of clinical significance. The aim of the present study was to establish a method which would allow the evaluation of oxidative susceptibility of LDL in the general clinical laboratory. RESULTS: LDL was isolated from human plasma by selective precipitation with amphipathic polymers. The ability of LDL to form peroxides was assessed by measuring thiobarbituric acid reactive substances (TBARS) after incubation with Cu(2+) and H(2)O(2). Reaction kinetics showed a three-phase pattern (latency, propagation and decomposition phases) which allowed us to select 150 min as the time point to stop the incubation by cooling and EDTA addition. The mixture Cu(2+)/H(2)O(2) yielded more lipoperoxides than each one on its own at the same time end-point. Induced peroxidation was measured in normal subjects and in type 2 diabetic patients. In the control group, results were 21.7 ± 1.5 nmol MDA/mg LDL protein, while in the diabetic group results were significantly increased (39.0 ± 3.0 nmol MDA/mg LDL protein; p < 0.001). CONCLUSION: a simple and useful method is presented for the routine determination of LDL susceptibility to peroxidation in a clinical laboratory
Fluoride Increases Superoxide Production and Impairs the Respiratory Chain in ROS 17/2.8 Osteoblastic Cells
It is known that fluoride produces oxidative stress. Inflammation in bone tissue and an impairment of the respiratory chain of liver have been described in treatments with fluoride. Whether the impairment of the respiratory chain and oxidative stress are related is not known. The aim of this work was to study the effects of fluoride on the production of superoxide radical, the function of the respiratory chain and the increase in oxidative stress in ROS 17/2.8 osteoblastic cells. We measured the effect of fluoride (100 mM) on superoxide production, oxygen consumption, lipid peroxidation and antioxidant enzymes activities of cultured cells following the treatment with fluoride. Fluoride decreased oxygen consumption and increased superoxide production immediately after its addition. Furthermore, chronic treatment with fluoride increased oxidative stress status in osteoblastic cells. These results indicate that fluoride could damage bone tissue by inhibiting the respiratory chain, increasing the production of superoxide radicals and thus of the others reactive oxygen speciesFil: Fina, Brenda. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Laboratorio de Biología Ósea; ArgentinaFil: Lombarte, Mercedes. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Laboratorio de Biología Ósea; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rigalli, Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Fisiología Experimental. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Fisiología Experimental; ArgentinaFil: Rigalli, Alfredo. Universidad Nacional de Rosario. Facultad de Ciencias Médicas. Laboratorio de Biología Ósea; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Влияние физической культуры на учебно-познавательную деятельность студентов
Ученые-неврологи нашли подтверждение тому, что регулярные физические упражнения позволяют учащимся не только сохранять и укреплять свое здоровье, но и способствуют учебным успехам. В частности, физкультура помогает повысить познавательные навыки и уровень внимания, что позволяет лучше справляться с учебной программой. Физическая активность помогает укреплять когнитивные возможности мозга, который в раннем возрасте находится в фазе активного развития. В результате возрастает общий показатель интеллекта и индекс умственной деятельностиРабота выполнена при финансовой поддержке Российского гуманитарного научного фонда, проект № 11-16-66502г/
Oxidative stress parameters in plasma of Huntington's disease patients, asymptomatic Huntington's disease gene carriers and healthy subjects : a cross-sectional study
BACKGROUND : Animal data and postmortem studies suggest a role of oxidative stress in the Huntington's disease (HD), but in vivo human studies have been scarce. ----- AIM : To assess the presence of oxidative stress in HD patients and its occurrence relative to clinical symptoms. ----- METHODS : Oxidative stress markers were determined in plasma of HD patients (n = 19), asymptomatic HD gene carriers (with > 38 CAG repeats) (n = 11) and their respective sex and agematched healthy controls (n = 47 and n = 22) in a cross-sectional study. ----- RESULTS : With adjustment for age and sex, HD patients had higher plasma lipid peroxidation (LP) levels (ratio 1.20, 95% CI 1.09 to 1.32, p < 0.001) and lower reduced glutathione (GSH) levels (ratio 0.72, CI 0.55 to 0.94, p = 0.011) than their age and sex-matched controls. Although considerably younger, HD gene carriers did not differ from HD patients regarding LP and GSH levels, and had higher plasma LP (ratio 1.16, CI 1.02 to 1.32, p = 0.016) and lower GSH than their matched controls (ratio 0.73, CI 0.5 to 1.05). They had higher LP (ratio 1.18, CI 1.02 to 1.34, p = 0.019) and lower GSH (ratio 0.75, CI 0.51 to 1.11) than the healthy subjects matched to HD patients. ----- CONCLUSIONS : Oxidative stress is more pronounced in HD patients and asymptomatic HD gene carriers than in healthy subjects. Differences in plasma LP and GSH are in line with the brain findings in animal models of HD. Data suggest that oxidative stress occurs before the onset of the HD symptoms
The effect of melatonin on bacterial translocation following ischemia/reperfusion injury in a rat model of superior mesenteric artery occlusion
Background: Acute mesenteric ischemia is a life-threatening vascular emergency resulting in tissue destruction due to ischemia-reperfusion injury. Melatonin, the primary hormone of the pineal gland, is a powerful scavenger of reactive oxygen species (ROS), including the hydroxyl and peroxyl radicals, as well as singlet oxygen, and nitric oxide. In this study, we aimed to investigate whether melatonin prevents harmful effects of superior mesenteric ischemia-reperfusion on intestinal tissues in rats. Methods: Rats were randomly divided into three groups, each having 10 animals. In group I, the superior mesenteric artery (SMA) was isolated but not occluded. In group II and group III, the SMA was occluded immediately distal to the aorta for 60 minutes. After that, the clamp was removed and the reperfusion period began. In group III, 30 minutes before the start of reperfusion, 10 mg/kg melatonin was administered intraperitonally. All animals were sacrified 24 hours after reperfusion. Tissue samples were collected to evaluate the I/R-induced intestinal injury and bacterial translocation (BT). Results: There was a statistically significant increase in myeloperoxidase activity, malondialdehyde levels and in the incidence of bacterial translocation in group II, along with a decrease in glutathione levels. These investigated parameters were found to be normalized in melatonin treated animals (group III). Conclusion: We conclude that melatonin prevents bacterial translocation while precluding the harmful effects of ischemia/reperfusion injury on intestinal tissues in a rat model of superior mesenteric artery occlusion. © 2015 Ozban et al.; licensee BioMed Central
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