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1.
《Saudi Journal of Biological Sciences》2017,24(8):1798-1802
ObjectiveTo study the protective effect of total flavonoid in rabdosia rubescens on BIT model by brain ischemic tolerance (hereinafter BIT) model of mice.MethodBIT model is used to block bilateral common carotid arteries and to copy BIT model of mice. After 10 min of transient ischemia for rats in preconditioning group, the mice in the nimodipine group and naoluotong capsule group were given the total flavonoid in rabdosia rubescens (300 mg/kg, 150 mg/kg, 75 mg/kg) for gavage, sham operation group, ischemia/reperfusion injury (hereinafter IRI) group and BIT group were fed with the same volume of 0.5% sodium carboxymethyl cellulose (CMC) once a day for 5 days. After administration for 1 h on day 5 (120 h), the rats in the other groups except for the sham operation group were treated with blood flow block for 30 min and reperfusion for 22 h. The serum NSE level were measured and the brain NO content and NOS activity changes was measured to observe the histopathological changes of brain tissue.ResultsBIT models of mice and in rats were both successfully replicated. The total flavonoid in rabdosia rubescens can decrease the mortality of mice, decrease serum NSE level, increase the content of NO and the activity of NOS in the brain tissue of mice, and improve the pathological damage of cortex and hippocampus of mice.ConclusionThe total flavonoid in rabdosia rubescens can stimulate an endogenous protective mechanism by inducing the release of low levels of cytokines NO and NOS, which reduces the release of serum NSE, relieves the brain tissue ischemia-reperfusion injury, and further improves the protection effect of ischemic preconditioning on brain injury. The damage of brain tissue ischemia and reperfusion, and further improve the ischemia Protective effect of preconditioning on brain injury. 相似文献
2.
P. Bourke D. Ziuzina L. Han P.J. Cullen B.F. Gilmore 《Journal of applied microbiology》2017,123(2):308-324
There is a diverse range of microbiological challenges facing the food, healthcare and clinical sectors. The increasing and pervasive resistance to broad‐spectrum antibiotics and health‐related concerns with many biocidal agents drives research for novel and complementary antimicrobial approaches. Biofilms display increased mechanical and antimicrobial stability and are the subject of extensive research. Cold plasmas (CP) have rapidly evolved as a technology for microbial decontamination, wound healing and cancer treatment, owing to the chemical and bio‐active radicals generated known collectively as reactive oxygen and nitrogen species. This review outlines the basics of CP technology and discusses the interactions with a range of microbiological targets. Advances in mechanistic insights are presented and applications to food and clinical issues are discussed. The possibility of tailoring CP to control specific microbiological challenges is apparent. This review focuses on microbiological issues in relation to food‐ and healthcare‐associated human infections, the role of CP in their elimination and the current status of plasma mechanisms of action. 相似文献
3.
To increase the menaquinone (MK) content of an Elizabethkingia meningoseptica, site-directed mutagenesis was generated to suppress 4-hydroxybenzoate octaprenyl transferase (UbiA) activity and subsequently blocked the ubiquinone (UQ) biosynthesis pathway. Fourteen conserved residues except L174 and G211 were mutated to analyze the effect of site-directed mutagenesis. The expression of UbiA in twelve mutants was decreased in both mRNA and protein levels, which resulted in the decrease of UQ concentration. Based on MenA expression level, 12 mutants were divided into two groups. Second group such as N72A, D76A, K81A, L139A, and D198A enhanced the expression of MenA, which increased MK production by 127.1%, 87.9%, 96.2%, 109.7% and 130.0% in wt-EmUbiA, respectively. In general, blocking UQ synthesis pathway for by site-directed mutagenesis of the active site of UbiA in E. meningoseptica was a promising strategy to increase MK production in E. meningoseptica. 相似文献
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5.
目的:探讨踝肱指数(ABI)与糖尿病周围神经病变及中医证候积分的相关性。方法:选取我院内分泌科收治辩证以气阴两虚
为证型的糖尿病患者66 例,根据踝肱指数实验将患者分为ABI降低组(0.9>ABI>0.5)和ABI 正常组(1.4>ABI>0.9)。记录患者神
经病变症状尼龙丝检查以及中医症候评分,分析ABI与糖尿病周围神经病变及中医证候积分的相关性。结果:ABI降低组的糖尿
病周围神经病变的患病率高于ABI正常组(P<0.05)。ABI 降低组发麻、针刺感症状的发生率高于ABI 正常组,且有统计学差异
(P<0.05)。ABI降低组10 g尼龙丝检查异常者多于ABI正常组,差异显著(P<0.05)。ABI降低组的感觉振动阈值高于ABI正常组
(P<0.05)。ABI数值与中医证候积分呈负向直线相关(P<0.05)。结论:糖尿病患者ABI数值与糖尿病周围神经病变和中医证候积
分具有相关性。 相似文献
6.
目的:桥本甲状腺炎是一种自身免疫性甲状腺疾病,且其发病率呈逐年上升趋势,在医疗实践中,HT 被认为是原发性甲状腺
功能减退最常见的原因,同时较易发生甲状腺癌和淋巴瘤。另外,HT 缺乏早期诊断标准,临床上发病隐匿且表现多样,病人多不
易察觉而延误治疗。本文旨在应用microRNA 芯片技术系统筛查HT病变甲状腺组织,以此研究并揭示其HT 的miRNA 表达谱
变化。方法:本研究首先采用microRNA芯片技术,对正常甲状腺组织及桥本甲状腺炎甲状腺组织中microRNA 的表达进行比较,
筛选桥本甲状腺炎中差异性表达的miRNAs。结果:与正常甲状腺相比,在桥本甲状腺炎及其合并甲状腺乳头状癌的一侧桥本甲
状腺炎中分别有39 个和25 个miRNAs 分子发生了差异性表达(P<0.05),比较2 组中共有的miRNAs 发现,miR-142-3p、
miR-338-3p、miR-454、miR-146a、miR-29b-1*、miR-150、miR-223 表达上调,miR-654-5p、miR-601、miR-198、miR-1226* 表达下调
(log2 FC≥ 2,P<0.05);而miR-142-5p 在原发性桥本甲状腺炎中表达显著性升高近8 倍(log2 FC=7.959,P<0.01)。结论:我们通
过microRNA芯片,首次直接系统筛查了桥本甲状腺炎病变组织相关miRNA 表达谱,总体上初步掌握了与正常甲状腺相比,桥
本甲状腺炎及合并甲状腺乳头状癌时其miRNA 表达谱的变化情况,为我们后续的研究提供了方向与基础。 相似文献
7.
目的:研究心脏康复运动对冠脉支架植入术后患者血脂、血糖、体重指数及生活质量的影响。方法:对实施冠脉支架植入术的
146例患者进行比较分析,根据随机原则分为试验组76 例及对照组70 例。对照组患者给予常规的健康教育及冠心病二级预防指
导,给予定期随访。试验组患者在此基础上给予规律的康复运动指导。经过6 个月随访,比较两组患者血脂、HbA1C、体重指数及
生活质量情况。结果:试验组患者通过为期6 个月的规律的心脏康复运动指导,其血脂、HbA1C等冠心病危险因素控制情况优于
对照组,差异有统计学意义(P<0.05)。同时,6个月后,试验组康复运动六月后sF 量表各项评分与对照组同期比较,差异均有统计
学意义(P<0.05)。结论:规范的心脏康复运动指导能够有效改善冠脉支架植入术后患者血脂、血糖情况,提高患者生活质量。 相似文献
8.
9.
Side chain flexibility and coupling between the S4‐S5 linker and the TRP domain in thermo‐sensitive TRP channels: Insights from protein modeling 下载免费PDF全文
The transient receptor potential (TRP) superfamily is subdivided into several subfamilies on the basis of sequence similarity, which is highly heterogeneous but shows a molecular architecture that resembles the one present in members of the Kv channel superfamily. Because of this diversity, they produce a large variety of channels with different gating and permeability properties. Elucidation of these particular features necessarily requires comparative studies based on structural and functional data. The present study aims to compilate, analyze, and determine, in a coherent way, the relationship between intrinsic side‐chain flexibility and the allosteric coupling in members of the TRPV, TRPM, and TRPC families. Based on the recently determined structures of TRPV1 and TRPV2, we have generated protein models for single subunits of TRPV5, TRPM8, and TRPC5 channels. With these models, we focused our attention on the apparently crucial role of the GP dipeptide at the center of the S4‐S5 linker and discussed its role in the interaction with the TRP domain, specifically with the highly‐conserved Trp during this coupling. Our analysis suggests an important role of the S4‐S5L flexibility in the thermosensitivity, where heat‐activated channels possess rigid S4‐S5 linkers, whereas cold‐activated channels have flexible ones. Finally, we also present evidence of the key interaction between the conserved Trp residue of the TRP box and of several residues in the S4‐S5L, importantly the central Pro. Proteins 2017; 85:630–646. © 2016 Wiley Periodicals, Inc. 相似文献
10.
Marco Dogs Bernd Wemheuer Laura Wolter Nils Bergen Rolf Daniel Meinhard Simon Thorsten Brinkhoff 《Systematic and applied microbiology》2017,40(6):370-382
Macroalgae harbour specific microbial communities on their surface that have functions related to host health and defence. In this study, the bacterial biofilm of the marine brown alga Fucus spiralis was investigated using 16S rRNA gene amplicon-based analysis and isolation of bacteria. Rhodobacteraceae (Alphaproteobacteria) were the predominant family constituting 23% of the epibacterial community. At the genus level, Sulfitobacter, Loktanella, Octadecabacter and a previously undescribed cluster were most abundant, and together they comprised 89% of the Rhodobacteraceae. Supported by a specific PCR approach, 23 different Rhodobacteraceae-affiliated strains were isolated from the surface of F. spiralis, which belonged to 12 established and three new genera. For seven strains, closely related sequences were detected in the 16S rRNA gene dataset. Growth experiments with substrates known to be produced by Fucus spp. showed that all of them were consumed by at least three strains, and vitamin B12 was produced by 70% of the isolates. Since growth of F. spiralis depends on B12 supplementation, bacteria may provide the alga with this vitamin. Most strains produced siderophores, which can enhance algal growth under iron-deficient conditions. Inhibiting properties against other bacteria were only observed when F. spiralis material was present in the medium. Thus, the physiological properties of the isolates indicated adaption to an epiphytic lifestyle. 相似文献