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121.
FK506 binding protein 12 (FK506BP) is a small peptide with a single FK506BP domain that is involved in suppression of immune response and reactive oxygen species. FK506BP has emerged as a potential drug target for several inflammatory diseases. Here, we examined the protective effects of directly applied cell permeable FK506BP (PEP-1-FK506BP) on corneal alkali burn injury (CAI). In the cornea, there was a significant decrease in the number of cells expressing pro-inflammation, apoptotic, and angiogenic factors such as TNF-α, COX-2, and VEGF. Both corneal opacity and corneal neovascularization (CNV) were significantly decreased in the PEP-1-FK506BP treated group. Our results showed that PEP-1-FK506BP can significantly inhibit alkali burn-induced corneal inflammation in rats, possibly by accelerating corneal wound healing and by reducing the production of angiogenic factors and inflammatory cytokines. These results suggest that PEP-1-FK506BP may be a potential therapeutic agent for CAI. [BMB Reports 2015; 48(11): 618-623]  相似文献   
122.
Eight propolis samples from Croatia were analyzed in detail, to study the headspace, volatiles, anti‐Varroa‐treatment residue, phenolics, and antioxidant properties. The samples exhibited high qualitative/quantitative variability of the chemical profiles, total phenolic content (1,589.3–14,398.3 mg GAE (gallic acid equivalent)/l EtOH extract), and antioxidant activity (11.1–133.5 mmol Fe2+/l extract and 6.2–65.3 mmol TEAC (Trolox® equivalent antioxidant capacity)/l extract). The main phenolics quantified by HPLC‐DAD at 280 and 360 nm were vanillin, p‐coumaric acid, ferulic acid, chrysin, galangin, and caffeic acid phenethyl ester. The major compounds identified by headspace solid‐phase microextraction (HS‐SPME), simultaneous distillation extraction (SDE), and subsequent GC‐FID and GC/MS analyses were α‐eudesmol (up to 19.9%), β‐eudesmol (up to 12.6%), γ‐eudesmol (up to 10.5%), benzyl benzoate (up to 28.5%), and 4‐vinyl‐2‐methoxyphenol (up to 18.1%). Vanillin was determined as minor constituent by SDE/GC‐FID/MS and HPLC‐DAD. The identified acaricide residue thymol was ca. three times more abundant by HS‐SPME/GC‐FID/MS than by SDE/GC‐FID/MS and was not detected by HPLC‐DAD.  相似文献   
123.
A comparison of instrumental neutron activation analysis (INAA) and proton-induced X-ray emission (PIXE) results for sizefractionated atmospheric aerosols (“coarse” and “fine” fractions with an equivalent aerodynamic diameter of 2–10 Μm and < 2 Μm, respectively, or the PM10 fraction) showed that PIXE yielded significantly lower results for the PM10 and coarse fractions, especially for elements with a low Z resulting from a particle size effect. Somewhat lower PIXE results were also obtained for the fine fraction of atmospheric aerosols. A correction is also needed for irregularly shaped deposits of combustion aerosols collected by a cascade impactor in 11 size fractions ranging from 0.016 to 14.3 Μm, as well as for thick samples of fly and bottom ashes. An equivalent layer thickness (ELT) model is proposed to correct the matrix effects in PIXE. The approaches for the calculation of ELT using a comparison of PIXE and INAA results or by comparing PIXE results obtained using two different incident proton beam energies (1.31 and 2.35 MeV) are described. The correction for the ash pellets and irregular deposits are also discussed.  相似文献   
124.
基于生态系统管理理论,从海洋投入强度、海洋利用强度、海洋经济效益及海洋生态环境质量层面,构建海域集约利用评价的指标体系,运用模糊决策分析理论计算各指标权重,得到河北省沿海地级市2005—2014年的海域集约利用综合指数,并利用聚类分析法及协调度指数对河北省海域集约利用的区域差异特征进行了分析。研究结果表明:2005—2014年河北省海域集约利用综合水平不断提高,除海洋生态环境质量准则层指数呈下降趋势外,海洋投入强度、海洋利用强度、海洋经济效益3个层面指数均呈上升趋势,其中持续增加趋势最明显的是海洋经济效益准则层;河北省沿海三市海域集约利用综合指数及各准则层指数的时序变化特征基本一致,但各区域之间仍体现着不同的变化特点,沧州市海域集约利用程度较高,唐山市海域集约利用经历了由低到高的过程,秦皇岛市海域集约利用的状况整体处于一般水平;河北省及沿海三市海域集约利用总体保持了较高的协调度,但各地区不同时段的变化特征有所不同。  相似文献   
125.
A temperature increase from 35° to 40–42°C enhances the rise of cytoplasmic serine proteinase (ISP1) activity in Bacillus megaterium incubated in a sporulation medium. A temperature shift from 27°C in the growth medium to 35°C in the sporulation medium has the same effect. Elevated temperature stimulates the increase of ISP1 level when applied immediately after the transfer of cells from the growth to the sporulation medium (at T0) or at T3, when sporulation becomes irreversible. The cytoplasmic PMSF-resistant activity or the proteolytic activity associated with the membrane fraction is stimulated only slightly or not at all. A temperature increase to 45–47°C suppresses the rise of proteolytic activities in all cell fractions. In addition to the elevation of the ISP1 activity by an upward temperature shift, the rise of this enzyme in nongrowing cells is also stimulated by osmotic stress. In growing populations, in contrast to the rise of the ISP1 activity caused by elevated temperature in nongrowing cells, this proteinase is induced by low temperatures (24–27°C). The ISP1 activity roughly correlates with the enzyme protein concentration determined by immunoblotting.  相似文献   
126.
Apolipoprotein E plays an important role in neurodegenerative processes in adulthood, whereas its neurodevelopmental role is uncertain. We aimed to study the effect of apolipoprotein E on neurodevelopment in a cohort liable to neurodevelopmental changes. The cohort consisted of very preterm (<32 gestational weeks) and/or very low birth weight (<1500 g) children, and the longitudinal follow‐up protocol included sequential cranial ultrasounds during infancy, brain magnetic resonance imaging at term‐equivalent age, neurological and cognitive assessment (Mental Developmental Index) at the corrected age of 2 years and cognitive and neuropsychological assessments (Wechsler Preschool and Primary Scale of Intelligence and Developmental NEuroPSYchological Assessment) at the chronological age of 5 years. Apolipoprotein E genotypes were determined from 322 children. Ultrasound and magnetic resonance imaging data were available for 321 (99.7%) and 151 (46.9%) children, respectively. Neurodevelopmental assessment data were available for 138 (42.9%) to 171 (53.1%) children. Abnormal findings in ultrasounds and magnetic resonance imaging were found in 163 (50.8%) and 64 (42.4%) children, respectively. Mild cognitive delay at the corrected age of 2 years and the chronological age of 5 years was suspected in 21 (12.3%) of 171 and 19 (13.8%) of 138 children, respectively. In the Developmental NEuroPSYchological Assessment, 47 (32.6%) of 144 children had significantly impaired performances in more than one study subtest. No associations between the apolipoprotein E genotypes and imaging findings or measured neurodevelopmental variables were found. Apolipoprotein E genotypes do not appear to have major impact on brain vulnerability or neurodevelopment in children .  相似文献   
127.
中国黄颡鱼的线粒体DNA多样性及其分子系统学   总被引:4,自引:0,他引:4  
基于体侧色斑、背鳍前部形态、吻长及尾柄长的差异, Ng和Kottelat(2007)将分布于中国的黄颡鱼群体划为两个物种: 北方群体为Pseudobagrus sinensis, 南方群体为P. fulvidraco。本研究通过对70个黄颡鱼标本相关形态特征的测量及对线粒体cyt b基因序列的分析, 探讨了P. sinensis物种的有效性问题。结果表明: 依据体侧色斑和背鳍前部形态的差异, 可将黄颡鱼分为对应于P. sinensisP. fulvidraco的两种形态类型, 但对尾柄长、吻长的测量发现二者没有差异。对70条cyt b基因序列的分析结果为: 两种鱼类有1个共同的单倍型; 两种鱼类的单系性在系统发育分析中都没有得到重现, 而二者聚在一起形成获得100%支持率的单系群; 两种鱼类群体之间存在持续的基因交流(Nm = 4.7); 两种鱼类在单倍型的巢式支系分析(nested clade analysis, NCA)中没有形成各自独立的进化谱系, 所有的单倍型以不超过5步的突变全部被纳入同一个进化网络中。因此我们认为P. sinensis不是有效物种, 而应被视为黄颡鱼的一种形态类型。基于cyt b基因的序列变异, 本研究对黄颡鱼群体的遗传多样性和种群结构作了初步分析。群体的核苷酸不配对分布及Tajima’sD中性检验表明, 约在10.1-14.1万年前, 黄颡鱼在其分布范围内经历过群体扩张, 推测这可能是导致黄颡鱼群体单倍型多样度高(h = 0.857 ± 0.0014)而核苷酸多样度低( π = 0.0023 ± 0.0003)的主要原因。此外, 分析结果显示黄颡鱼群体缺乏明显的地理结构, 推测原因可能是历史上水系的连通促进了不同地理群体之间的基因交流。  相似文献   
128.
刘舒婷  苏杨  姚玉峰 《微生物学报》2017,57(11):1698-1707
蛋白质翻译后修饰是调控蛋白质生物学功能的重要步骤之一。甲基化修饰作为蛋白质翻译后修饰的一种重要形式,参与了真核生物和原核生物的多种细胞进程。本文综述了目前蛋白质甲基化的研究进展,包括真核生物、原核生物,组蛋白和非组蛋白,以及多种氨基酸位点的甲基化修饰。这些发现丰富了人们对蛋白质甲基化修饰的认识,对深入了解蛋白质翻译后修饰的功能具有重要意义。  相似文献   
129.
The halophyte Mesembryanthemum crystallinum (ice plant) has been suggested as a model for salt-tolerance in higher plants. To investigate salt-induced changes in polypeptide patterns at the cellular level, a light-grown callus of M. crystallinum with substantial chlorophyll content, was established and the effect of NaCl on the composition of phenol-extracted protein was examined by SDS- and 2D-polyacrylamide gel electrophoresis (PAGE). SDS-PAGE showed the accumulation of five polypeptides with estimated molecular masses of 40, 34, 32, 29 and 14 kDa was enhanced by the addition of 200 m M NaCl to the culture media. The addition of ABA (10 μ M ) or mannitol (400 m M ) did not elicit the same degree of accumulation of these salt-specific proteins. These polypeptides were classified into two groups according to their course of induction: early responsive (40, 34, 29 kDa) and late-responsive (32, 14 kDa) proteins. In addition, two polypeptides (20, 18 kDa) were transiently accumulated during salt treatment. Further separation of soluble proteins by 2-D gel electrophoresis, either isoelectric focusing (IEF) or non-equilibrium pH-gradient electrophoresis (NEPHGE) followed by SDS-PAGE, showed more alterations in accumulation of polypeptides by NaCl than 1-D gel electrophoresis. Overall, levels of more than 30% of basic polypeptides, detected by NEPHGE/SDS-PAGE, were altered by 200 m M NaCl treatment, while only 10% of neutral and acidic polypeptides, detected by IEF/SDS-PAGE, were changed. The enhanced expression of these proteins by salt in cultured cells is most likely related to the cellular responses to salinity, and not to the mechanism of CAM induction in this facultative halophyte.  相似文献   
130.
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