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41.
Nesim Alada Ramazan Asolu Mahmut Ozdemir Emin Asolu Atabey Rukiye Derin Canan Demir Halit Demir 《Journal of Medical Biochemistry》2021,40(3):286
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
42.
Muhammad Nasir Chen-chen Zhao Jun-yu Luo Xiang-zhen Zhu Xue-ke Gao Mazher F. Iqbal Ji-chao Ji Shuai Zhang Jin-jie Cui 《Journal of Asia》2021,24(1):297-307
The genetically modified cotton holding Bt proteins, is noxious to bollworms larvae but very little is known about its impact on population of non-target spiders within the field. Studies conducted with the aim to identify spiders along with their abundance, prevalence pattern, preying habit on insect pests in Bt cotton (L280, Cry2Ab4) and commonness of symbiotic bacteria in these spiders. Spiders collections were made via vial tapping/jarring, from May to end of October (2018). In total, 13,342 spiders were recorded during the entire cropping season. Least relative abundance was in May (0.28%), highest in August (30.39%) while ahead decline was observed, reached to 12% in October. The 27 species were verified, least richness was in May (3 species), high in August (19 species), later in the end, reduced to 7 species. High abundance was of Hylyphantes graminicola (68.56%) and Neoscona theisi (19.98%). Existence of H. graminicola and Pardosa astrigera observed during the whole cropping season. Presence of seven guilds among spiders had a diverse nature of hunting insect pests and on number of species existed in the crop, maximum was from direct hunting habit. Composition and community structure of microbiota varied as of spider species. Proteobacteria was the most abundant bacterial phylum and topmost genus was Wolbachia in observed spiders. Five groups of bacteria distinguished across 4 clusters of spiders depending on core community of symbiotic bacterial genera. This effort is an initial step to get knowhow about spiders in Bt cotton, which will facilitate future research studies concerning spiders. 相似文献
43.
环状RNA(circular RNAs,circRNAs)是一类共价闭合环状非编码RNA,具有进化上保守、结构上稳定、组织特异性表达等特点。CircRNAs可作为miRNAs海绵影响其对基因的调控,还可与RNA结合蛋白(RNA binding proteins,RBPs)相互作用,也有研究表明某些circRNAs还具有被翻译成蛋白质的潜能。CircRNAs已被证实对某些疾病具有特异性、稳定性和调节功能,如癌症、糖尿病、心血管疾病、神经退行性疾病等,其可作为潜在的诊断、预后生物标志物和治疗靶点。最近,有研究发现circRNAs参与了环境化学污染物诱导的毒性效应发生及发展的过程。目前,生态毒理学研究中评价环境化学污染物和毒效应之间关系的毒性终点通常会受遗传多态性和表观遗传学影响,考虑到经环境化学污染物暴露后生物体内circRNAs差异性表达的现象,或许在生态毒理学研究中circRNAs也有作为生物标志物的可能性。基于此,对circRNAs的生物合成与降解、生物学功能、分析方法及其目前在生态毒理学研究中的应用展开综述,并对其作为分子生物标志物在环境污染物暴露早期诊断和生态风险评价中的应用进行了展望,以期为生态毒理学研究和环境风险评价提供参考。 相似文献
44.
Beatris Mastelic Nathalie Garçon Giuseppe Del Giudice Hana Golding Marion Gruber Pieter Neels Bernard Fritzell 《Biologicals》2013,41(6):458-468
Vaccination represents one of the greatest public health triumphs; in part due to the effect of adjuvants that have been included in vaccine preparations to boost the immune responses through different mechanisms. Although a variety of novel adjuvants have been under development, only a limited number have been approved by regulatory authorities for human vaccines. This report reflects the conclusions of a group of scientists from academia, regulatory agencies and industry who attended a conference on the current state of the art in the adjuvant field. Held at the U.S. Pharmacopeial Convention (USP) in Rockville, Maryland, USA, from 18 to 19 April 2013 and organized by the International Association for Biologicals (IABS), the conference focused particularly on the future development of effective adjuvants and adjuvanted vaccines and on overcoming major hurdles, such as safety and immunogenicity assessment, as well as regulatory scrutiny. More information on the conference output can be found on the IABS website, http://www.iabs.org/. 相似文献
45.
Marta Cal Mariusz Jaremko Łukasz Jaremko Piotr Stefanowicz 《Journal of peptide science》2013,19(1):9-15
A novel resin designed for solid‐phase synthesis of peptide hydroxamic acids (PHA) combining the trityl linker with poly(ethylene glycol)‐based support, ChemMatrix® type, is described. The synthesis of PHA can be performed according to a standard protocol, providing products in excellent purity and reasonable yields. Copyright © 2012 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
46.
Stefan Milton Raunak Esther Yeheskiely Roger Strömberg 《Nucleosides, nucleotides & nucleic acids》2013,32(10-12):1495-1499
In order to obtain higher quality 2 ′-O-carbamoylmethyl oligoribonucleotides we are conducting studies of this modification. Here we present synthesis of 2 ′-O-carbamoylmethyl containing H-phosphonate building blocks as well as synthesis of model dinucleotides needed for these studies. 相似文献
47.
Kohjiro Nagao Minami Maeda Noralyn B. Mañucat Kazumitsu Ueda 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2013,1831(2):398-406
ATP-binding cassette protein A1 (ABCA1) plays a key role in generating high-density lipoprotein (HDL). However, the detailed mechanism of HDL formation remains unclear; in order to reveal it, chemicals that specifically block each step of HDL formation would be useful. Cyclosporine A inhibits ABCA1-mediated cholesterol efflux, but it is not clear whether this is mediated via inhibition of calcineurin. We analyzed the effects of cyclosporine A and related compounds on ABCA1 function in BHK/ABCA1 cells. Cyclosporine A, FK506, and pimecrolimus inhibited ABCA1-mediated cholesterol efflux in a concentration-dependent manner, with IC50 of 7.6, 13.6, and 7.0 μM, respectively. An mTOR inhibitor, rapamycin also inhibited ABCA1, with IC50 of 18.8 μM. The primary targets for these drugs were inhibited at much lower concentrations in BHK/ABCA1 cells, suggesting that they were not involved. Binding of [3H] cyclosporine A to purified ABCA1 could be clearly detected. Furthermore, a non-immunosuppressive cyclosporine, PSC833, inhibited ABCA1-mediated cholesterol efflux with IC50 of 1.9 μM, and efficiently competed with [3H] cyclosporine A binding to ABCA1. These results indicate that cyclosporine A and PSC833 inhibit ABCA1 via direct binding, and that the ABCA1 inhibitor PSC833 is an excellent candidate for further investigations of the detailed mechanisms underlying formation of HDL. 相似文献
48.
转基因低水平混杂问题——政策与内涵 总被引:1,自引:0,他引:1
转基因技术近年来在世界范围内快速发展,但由于不同国家在转基因审批上的不同步,以及各国设立严格的转基因低水平混杂阈值,导致正常的农产品贸易由于无意混入少量转基因成分而发生贸易摩擦,甚至导致贸易中断.从转基因低水平混杂(LLP)的含义出发分析其特殊性,分析了世界主要国家的LLP政策以及严格的LLP政策对贸易产生的负面影响.根据研究结果指出:在当前转基因作物采用率不断提高,以及转基因新品种研发加速背景下,转基因低水平混杂在技术上是不可避免的.因此,有必要在全球范围内建立转基因安全互信机制,各国需要尽量减少审批不同步时滞,设置合理的转基因低水平阈值,降低对正常贸易的负面影响.研究结果对中国转基因LLP政策和有关标准制定有一定借鉴意义. 相似文献
49.
Scott J Diede Zizhen Yao C Chip Keyes Ashlee E Tyler Joyoti Dey Christopher S Hackett Katrina Elsaesser Christopher J Kemp Paul E Neiman William A Weiss James M Olson Stephen J Tapscott 《Epigenetics》2013,8(12):1254-1260
Genetic and epigenetic alterations are essential for the initiation and progression of human cancer. We previously reported that primary human medulloblastomas showed extensive cancer-specific CpG island DNA hypermethylation in critical developmental pathways. To determine whether genetically engineered mouse models (GEMMs) of medulloblastoma have comparable epigenetic changes, we assessed genome-wide DNA methylation in three mouse models of medulloblastoma. In contrast to human samples, very few loci with cancer-specific DNA hypermethylation were detected, and in almost all cases the degree of methylation was relatively modest compared with the dense hypermethylation in the human cancers. To determine if this finding was common to other GEMMs, we examined a Burkitt lymphoma and breast cancer model and did not detect promoter CpG island DNA hypermethylation, suggesting that human cancers and at least some GEMMs are fundamentally different with respect to this epigenetic modification. These findings provide an opportunity to both better understand the mechanism of aberrant DNA methylation in human cancer and construct better GEMMs to serve as preclinical platforms for therapy development. 相似文献
50.
Fish models are essential for research in many biological and medical disciplines. With a typical lifespan of only 6 months, the Turquoise killifish (Nothobranchius furzeri) was recently established as a time- and cost-efficient model to facilitate whole-life and multigenerational studies in several research fields, including behavioural ecotoxicology. Essential information on the behavioural norm and on how laboratory conditions affect behaviour, however, is deficient. In the current study, we examined the impact of the social and structural environment on a broad spectrum of behavioural endpoints in N. furzeri. While structural enrichment affected only fish boldness and exploratory behaviour, fish rearing density affected the total body length, locomotor activity, boldness, aggressiveness and feeding behaviour of N. furzeri individuals. Overall, these results contribute to compiling a behavioural baseline for N. furzeri that increases the applicability of this new model species. Furthermore, our findings will fuel the development of improved husbandry protocols to maximize the welfare of N. furzeri in a laboratory setting. 相似文献