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71.
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Catalase enzyme (H2O2: oxidoreductase; E.C. 1.11.1.6) was purified from human skin homogenate using ammonium sulfate precipitation and DEAE-Sephadex A50 ion exchange chromatography at 4°C and some characteristics of the enzyme were investigated. The human skin enzyme, having a specific activity of 1354.5 EU/mg proteins was purified with a yield of 43.13% and 1110-fold. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed a single band for the enzyme. Inhibition by piroxicam, ketoprofen, diclofenac sodium, sulfamethoxazole and nidazole occurred with I50 values of 0.414, 1.29, 1.8, 3.83, and 8.64 mM, respectively.  相似文献   
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Vaccinomics is the convergence of vaccinology and population-based omics sciences. The success of knowledge-based innovations such as vaccinomics is not only contingent on access to new biotechnologies. It also requires new ways of governance of science, knowledge production, and management. This article presents a conceptual analysis of the anticipatory and adaptive approaches that are crucial for the responsible design and sustainable transition of vaccinomics to public health practice. Anticipatory governance is a new approach to manage the uncertainties embedded on an innovation trajectory with participatory foresight, in order to devise governance instruments for collective "steering" of science and technology. As a contrast to hitherto narrowly framed "downstream impact assessments" for emerging technologies, anticipatory governance adopts a broader and interventionist approach that recognizes the social construction of technology design and innovation. It includes in its process explicit mechanisms to understand the factors upstream to the innovation trajectory such as deliberation and cocultivation of the aims, motives, funding, design, and direction of science and technology, both by experts and publics. This upstream shift from a consumer "product uptake" focus to "participatory technology design" on the innovation trajectory is an appropriately radical and necessary departure in the field of technology assessment, especially given that considerable public funds are dedicated to innovations. Recent examples of demands by research funding agencies to anticipate the broad impacts of proposed research--at a very upstream stage at the time of research funding application--suggest that anticipatory governance with foresight may be one way how postgenomics scientific practice might transform in the future toward responsible innovation. Moreover, the present context of knowledge production in vaccinomics is such that policy making for vaccines of the 21st century is occurring in the face of uncertainties where the "facts are uncertain, values in dispute, stakes high and decisions urgent and where no single one of these dimensions can be managed in isolation from the rest." This article concludes, however, that uncertainty is not an accident of the scientific method, but its very substance. Anticipatory governance with participatory foresight offers a mechanism to respond to such inherent sociotechnical uncertainties in the emerging field of vaccinomics by making the coproduction of scientific knowledge by technology and the social systems explicit. Ultimately, this serves to integrate scientific and social knowledge thereby steering innovations to coproduce results and outputs that are socially robust and context sensitive.  相似文献   
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Our aim was to evaluate whether atrial electromechanical delay measured by tissue Doppler imaging (TDI), which is an early predictor of atrial fibrillation (AF) development, is prolonged in obese subjects. A total of 40 obese and 40 normal‐weight subjects with normal coronary angiograms were included in this study. P‐wave dispersion (PWD) was calculated on the 12‐lead electrocardiogram (ECG). Systolic and diastolic left ventricular (LV) functions, inter‐ and intra‐atrial electromechanical delay were measured by TDI and conventional echocardiography. Inter‐ and intra‐atrial electromechanical delay were significantly longer in the obese subjects compared with the controls (44.08 ± 10.06 vs. 19.35 ± 5.94 ms and 23.63 ± 6.41 vs. 5.13 ± 2.67 ms, P < 0.0001 for both, respectively). PWD was higher in obese subjects (53.40 ± 5.49 vs. 35.95 ± 5.93 ms, P < 0.0001). Left atrial (LA) diameter, LA volume index and LV diastolic parameters were significantly different between the groups. Interatrial electromechanical delay was correlated with PWD (r = 0.409, P = 0.009), high‐sensitivity C‐reactive protein (hsCRP) levels (r = 0.588, P < 0.0001). Interatrial electromechanical delay was positively correlated with LA diameter, LA volume index, and LV diastolic function parameters consisting of mitral early wave (E) deceleration time (DT) and isovolumetric relaxation time (IVRT; r = 0.323, P = 0.042; r = 0.387, P = 0.014; r = 0.339, P = 0.033; r = 0.325, P = 0.041; respectively) and, negatively correlated with mitral early (E) to late (A) wave ratio (E/A) (r = ?0.380, P = 0.016) and myocardial early‐to‐late diastolic wave ratio (Em/Am) (r = ?0.326, P = 0.040). This study showed that atrial electromechanical delay is prolonged in obese subjects. Prolonged atrial electromechanical delay is due to provoked low‐grade inflammation as well as LA enlargement and early LV diastolic dysfunction in obese subjects.  相似文献   
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Members of the acyl-CoA thioesterase (Acot) gene family hydrolyze fatty acyl-CoAs, but their biological functions remain incompletely understood. Thioesterase superfamily member 2 (Them2; synonym Acot13) is enriched in oxidative tissues, associated with mitochondria, and relatively specific for long chain fatty acyl-CoA substrates. Using Them2−/− mice, we have demonstrated key roles for Them2 in regulating hepatic glucose and lipid metabolism. However, reduced body weights and decreased adiposity in Them2−/− mice observed despite increased food consumption were not well explained. To explore a role in thermogenesis, mice were exposed to ambient temperatures ranging from thermoneutrality (30 °C) to cold (4 °C). In response to short term (24-h) exposures to decreasing ambient temperatures, Them2−/− mice exhibited increased adaptive responses in physical activity, food consumption, and energy expenditure when compared with Them2+/+ mice. By contrast, genotype-dependent differences were not observed in mice that were equilibrated (96 h) at each ambient temperature. In brown adipose tissue, the absence of Them2 was associated with reduced lipid droplets, alterations in the ultrastructure of mitochondria, and increased expression of thermogenic genes. Indicative of a direct regulatory role for Them2 in heat production, cultured primary brown adipocytes from Them2−/− mice exhibited increased norepinephrine-mediated triglyceride hydrolysis and increased rates of O2 consumption, together with elevated expression of thermogenic genes. At least in part by regulating intracellular fatty acid channeling, Them2 functions in brown adipose tissue to suppress adaptive increases in energy expenditure.  相似文献   
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Tuna  Esin  Ersoy  Yeliz Emine  Bulut  Pelin  Ozdemir  Filiz  Buyru  Nur 《Molecular biology reports》2020,47(3):1605-1612
Molecular Biology Reports - Breast cancer, which is the most common type of cancer among women, is a heterogenous disease. It results from progressive accumulation of genetic and epigenetic...  相似文献   
78.
The effect of chronic long-term intermittent hypobaric hypoxia (CLTIHH) on blood rheology is not completely investigated. We designed this study to determine the effect of CLTIHH on blood rheology parameters. Present study was performed in 16 male Spraque-Dawley rats that divided into CLTIHH and Control groups. To obtain CLTIHH, rats were placed in a hypobaric chamber (430 mmHg; 5 hours/day, 5 days/week, 5 weeks). The control rats stayed in the same environment as the CLTIHH rats but they breathed room air. In the blood samples aspirated from the heart, hematocrit, whole blood viscosity, plasma viscosity, plasma fibrinogen concentration, erythrocyte rigidity index and oxygen delivery index were determined. The whole blood viscosity, plasma viscosity, hematocrit and fibrinogen concentration values in the CLTIHH group were found to be higher than those of the control group. However, no significant difference was found in erythrocyte rigidity index and oxygen delivery index between the groups. Our results suggested that CLTIHH elevated whole blood viscosity by increasing plasma viscosity, fibrinogen concentration and hematocrit value without effecting the erythrocyte deformability. Hence, CLTIHH that may occur in intermittent high altitude exposure and some severe obstructive sleep apnea (OSA) patients may be responsible for hemorheologic changes in those subjects.  相似文献   
79.
Morphine is widely used to treat chronic pain, however its utility is hindered by the development of tolerance to its analgesic effects. The aim of this study was to investigate effects of fluoxetine, a specific serotonin (5-HT) reuptake inhibitor, and LY 367265, an inhibitor of the 5-HT transporter and 5-HT2A receptor antagonist, on tolerance induced to the analgesic effect of morphine in rats. The study was carried out on male Wistar Albino rats (weighing 170-190 g). To constitute morphine tolerance, animals received morphine (50 mg/kg; s.c.) once daily for 3 days. After last dose of morphine, injected on day 4, morphine tolerance was evaluated. The analgesic effects of fluoxetine (10 mg/ kg; i.p.), LY 367265 (3 mg/kg; i.p.) and morphine were considered at 30-min intervals by tail-flick and hot-plate tests. The results showed that fluoxetine and LY 367265 significantly attenuated the development and expression of morphine tolerance. The maximal antinociceptive effects were obtained 30 min after administration of fluoxetine and 60 min after administration of LY 367265. In conclusion, we observed that co-injection of morphine with fluoxetine and LY 367265 increased the analgesic effects of morphine and delayed development of tolerance to morphine analgesia.  相似文献   
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We studied intraguild predation of Serangium parcesetosum on Eretmocerus mundus, both natural enemies of Bemisia tabaci, on eggplant under laboratory conditions. Fourth instar and adult predators attacked parasitized and unparasitized hosts equally if immature parasitoids were larvae, but avoided predating on parasitized hosts containing pupae.  相似文献   
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