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1.
A new species, Cephalaria tuteliana, (Dipsacaceae) from the European part of Turkey is described and illustrated. The characteristics of the new species, and its relationships with Cephalaria tenuiloba is discussed.  相似文献   
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Abstract

Immobilization of enzymes from different sources on various supports in designed systems increases enzymes’ stability by protecting the active site of it from undesired effect of reaction environment. Also, immobilization decreases the cost of separation and facilities the reuse of the enzymes. Therefore, the design of new immobilization enzyme preparations has been an inevitable area of modern biotechnology. Herein, Rhizomucor miehei lipase (RML) was immobilized on montmorillonite K-10 (MMT-RML) by adsorption and in polyvinyl alcohol (PVA-RML) by entrapment to obtain a more stable and active lipase preparation. The free and immobilized lipase preparations were characterized for p-nitrophenyl palmitate hydrolysis. The apparent Michaelis–Menten (Kmapp) constant was almost the same for the free RML and PVA-RML, whereas the corresponding value was 17.7-fold lower for MMT-RML. PVA-RML and MMT-RML have shown a 1.1 and 23.8 folds higher catalytic efficiency, respectively, than that of the free RML. The half-lives of PVA-RML and MMT-RML were found to be 7.4 and 3.4 times longer than the free RML at 35?°C, respectively. PVA-RML and MMT-RML maintained 65% and 87% of their initial activities after four reuses. These results showed that the catalytic performance of RML has improved significantly by immobilization.  相似文献   
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BackgroundCoronary ischemia can lead to myocardial damage and necrosis. The pathogenesis of cardiovascular diseases often includes increased oxidative stress and decreased antioxidant defense. The study aimed to assess levels of ischemia modified albumin (IMA), malondialdehyde acid (MDA), superoxide dismutase (SOD), and catalase in individuals diagnosed with ST elevated myocardial infarction (STEMI) and non-STEMI.MethodsThe present study prospectively included 50 STEMI patients, 55 NSTEMI patients, and 55 healthy subjects. Only patients who were recently diagnosed with STEMI or NSTEMI were included in this study. IMA, MDA, SOD, and catalase activities were measured spectrophotometrically. Significant coronary artery lesions were determined by angiography.ResultsPatients with ACS had significantly greater IMA and MDA values than the healthy controls (p<0.001). Besides, patients with STEMI had IMA levels that were significantly greater than those of the patients with NSTEMI (p<0.001), while the reverse was true for MDA levels (p<0.001). The healthy controls had the highest levels of SOD and catalase levels, followed by patients with STEMI and patients with NSTEMI, respectively (p<0.001). There was a significant negative correlation among MDA and SOD with catalase levels (r = -0.771 p<0.001 MDA vs catalase; r = -0.821 p<0.001 SOD vs catalase).ConclusionsData obtained in this study reveals that compared to healthy controls, STEMI and NSTEMI patients had increased levels of MDA and IMA and decreased levels of SOD and catalase.  相似文献   
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Testicular cancer is the most common cancer among young men of reproductive age. Bleomycin is a frequently used drug for the treatment of several malignancies and is part of the chemotherapy protocols in testicular cancer. Bleomycin causes an increase in oxidative stress which has been shown to induce apoptosis in cancer cells. Curcumin (diferuloylmethane), an active component of the spice turmeric, has attracted interest because of its anti-inflammatory and chemopreventive activities. However, no study has been carried out so far to elucidate its interaction with bleomycin in testicular cancer cells. In this study, we investigated the effects of curcumin and bleomycin on apoptosis signalling pathways and compared the effects of bleomycin with H2O2 which directly produces reactive oxygen species. We measured apoptosis markers such as caspase-3, caspase-8, and caspase-9 activities and Bcl-2, Bax, and Cyt-c levels in NCCIT cells incubated with curcumin (5 μM), bleomycin (120 μg/ml), bleomycin + curcumin, H2O2 (35 μM), and H2O2 + curcumin for 72 h. Curcumin, bleomycin, and H2O2 caused apoptosis indicated as increases in caspase-3, caspase-8, and caspase-9 activities and Bax and cytoplasmic Cyt-c levels and a decrease in Bcl-2 level. Concurrent use of curcumin with bleomycin decreased caspase activities and Bax and Cyt-c levels compared to their separate effects in NCCIT cells. Our findings suggest that concurrent use of curcumin during chemotherapy in testis cancer should be avoided due to the inhibitory effect of curcumin on bleomycin-induced apoptosis.  相似文献   
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The problem of inadequate access to water, sanitation and hygiene (WASH) in less-developed nations has received much attention over the last several decades (most recently in the Millennium Development Goals), largely because diseases associated with such conditions contribute substantially to mortality in poor countries. We present country-level projections for WASH coverage and for WASH-related mortality in developing regions over a long time horizon (1975–2050) and provide dynamic estimates of the economic value of potential reductions in this WASH-related mortality, which go beyond the static results found in previous work. Over the historical period leading up to the present, our analysis shows steady and substantial improvements in WASH coverage and declining mortality rates across many developing regions, namely East Asia and the Pacific, Latin America and the Caribbean, Eastern Europe and the Middle East. The economic value of potential health gains from eliminating mortality attributable to poor water and sanitation has decreased substantially, and in the future will therefore be modest in these regions. Where WASH-related deaths remain high (in parts of South Asia and much of Sub-Saharan Africa), if current trends continue, it will be several decades before economic development and investments in improved water and sanitation will result in the capture of these economic benefits. The fact that health losses will likely remain high in these two regions over the medium term suggests that accelerated efforts are needed to improve access to water and sanitation, though the costs and benefits of such efforts in specific locations should be carefully assessed.  相似文献   
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The etiopathogenesis of Graves’ disease (GD) has not been clearly elucidated although the role of chronical inflammation and endothelial dysfunction has been established. Adhesion molecules such as intercellular adhesion molecule 1 (ICAM1), vascular cell adhesion molecule 1 (VCAM1), and E-selectin are secreted from vascular endothelium and promote accummulation of leukocytes in damaged endothelial areas. This study examined the possible association of ICAM1 (G241R and K469E), VCAM1 (T-1591C and T-833C), and E-selectin (S128R) single nucleotide polymorphisms (SNPs) with the occurence of GD. ICAM1 (G241R and K469E), VCAM1 (T-1591C and T-833C), and E-selectin (S128R) SNPs in DNA from peripheral blood leukocytes of 171 patients with GD and 259 healthy controls were investigated by real-time PCR combined with melting curve analysis using fluorescence-labeled hybridization probes. We did not find significant differences in the distributions of studied polymorphisms, nor in the haplotype frequencies between patients with GD and healthy control. However, the anti-TPO levels in E-selectin 128R allele carrying subjects (SR + RR) were higher than S128S genotype (p < 0.05). In addition, the decline of TSH levels was more prominent in ICAM1 469 E carrying subjects (KE + EE) in comparison with wild homozygotes (p < 0.05). Although there is not assosiation between ICAM1 (G241R and K469E), VCAM1 (T-1591C and T-833C), and E-selectin (S128R) SNPs and susceptibility to GD, higher anti-TPO in E-selectin 128 SR + RR, and lower TSH in ICAM1 469 KE + EE subjects suspect that these genotypes are prone to increased antithyroid autoantibody production with more accentuated TSH suppression in GD. Further studies with a larger cohort, analyzing other polymorphisms in ICAM, VCAM1 and E-selectin genes are necessary to support our observations.  相似文献   
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Antioxidants may prevent apoptosis of cancer cells via inhibiting reactive oxygen species (ROS). However, to date no study has been carried out to elucidate the effects of strong antioxidant N‐acetylcysteine (NAC) on Bleomycin induced apoptosis in human testicular cancer (NTERA‐2, NT2) cells. For this reason, we studied the effects of Bleomycin and NAC alone and in combination on apoptotic signaling pathways in NT2 cell line. We determined the cytotoxic effect of bleomycin on NT2 cells and measured apoptosis markers such as Caspase‐3, ‐8, ‐9 activities and Bcl‐2, Bax, Cyt‐c, Annexin V‐FTIC and PI levels in NT2 cells incubated with different agents for 24 h. Early apoptosis was determined using FACS assay. We found half of the lethal dose (LD50) of Bleomycin on NT2 cell viability as 400, 100, and 20 µg/ml after incubations for 24, 48, and 72 h, respectively. Incubation with bleomycin (LD50) and H2O2 for 24 h increased Caspase‐3, ‐8, ‐9 activities, Cyt‐c and Bax levels and decreased Bcl‐2 levels. The concurrent incubation of NT2 cells with bleomycin/H2O2 and NAC (5 mM) for 24 h abolished bleomycin/H2O2‐dependent increases in Caspase‐3, ‐8, ‐9 activities, Bax and Cyt‐c levels and bleomycin/H2O2‐dependent decrease in Bcl‐2 level. Our results indicate that bleomycin/H2O2 induce apoptosis in NT2 cells by activating mitochondrial pathway of apoptosis, while NAC diminishes bleomycin/H2O2 induced apoptosis. We conclude that NAC has antagonistic effects on Bleomycin‐induced apoptosis in NT2 cells and causes resistance to apoptosis which is not a desired effect in eliminating cancer cells. J. Cell. Biochem. 114: 1685–1694, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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The present study was conducted to explore the possible effects of different doses of lithium carbonate on thyroid functions, erythrocyte oxidant–antioxidant status, and osmotic fragility. Twenty-four Wistar-type male rats were equally divided into three groups: groups I and II received 0.1 and0.2 % lithium carbonate in their drinking water, respectively, for 30 days. The rats in group III served as controls, drinking tap water without added lithium. At the end of the experimental period, the erythrocyte osmotic fragility and the levels of triiodothyronine (T3), thyroxine (T4), thyroid-stimulating hormone (TSH), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) were measured in blood samples. Compared to controls, there was a statistically significant increase of TSH but decreases of the T3 and T4 levels in group II. Both experimental groups showed a statistically significant increase of the maximum osmotic fragility limit. The minimum osmotic fragility values of the animals in group II were statistically higher than those of controls. The standard hemolytic increment curve of both experimental groups was shifted to the right when compared to the curve obtained from the controls. Also, relative to controls, the activities of MDA and SOD were significantly higher and the GSH level lower in group II, but not so in group I. The results of the present study show that treatment with lithium carbonate may result in thyroid function abnormalities, increased oxidative damage, and possible compromise of the erythrocyte membrane integrity resulting from increased osmotic fragility.  相似文献   
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A series of benzenesulfonamides incorporating cyanoacrylamide moieties (tyrphostine analogs) were assayed as inhibitors of the β-carbonic anhydrase (CA, EC 4.2.1.1) from Saccharomyces cerevisiae, ScCA. Some of these compounds were low nanomolar or subnanomolar ScCA inhibitors and showed selectivity ratios in the range of 4.91–69.86 for inhibiting the yeast enzyme over the offtarget human (h) isoforms hCA I and of 6.46–13.52 for inhibiting ScCA over hCA II. The model organism S. cerevisiae and this particular enzyme may be useful for detecting antifungals with a novel mechanism of action compared to the classical azole drugs to which significant drug resistance emerged. Indeed, some of these sulfonamides inhibited the growth of the yeast with CC50-s in the range of 0.73–6.54 μM.  相似文献   
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