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141.
Emerging evidence suggests that a high-fat diet (HFD) can influence endoplasmic reticulum (ER) stress and gut microbiota. Crataegi Fructus is a traditional Chinese herb widely used in formulas for dyspepsia, with Dashanzha Pill composed of raw Crataegi Fructus (DR) being a representative drug. Processing products of Crataegi Fructus, however, have a stronger pro-digestive effect, and we hypothesized that Dashanzha Pill composed of charred Crataegi Fructus (DC) is more effective. We found that the contents of glucose 1-phosphate and luteolin in DR and DC were substantially different via ultra-high performance liquid chromatography-hybrid quadrupole-Orbitrap high-resolution mass spectrometry. DC outperformed DR in improving histopathological changes, increasing gastrin and motilin, and decreasing vasoactive intestinal peptides in rats with HFD induced dyspepsia. Fecal microbiota analysis revealed that DC could restore the disturbed intestinal microbiota composition, including that of Bacteroides, Akkermansia, and Intestinimonas to normal levels. Furthermore, DC significantly reduced the mRNA and protein levels of glucose-regulated protein 78, protein kinase R-like ER kinase, and eukaryotic initiation factor 2α. Taken together, DC outperformed DR in relieving dyspepsia by regulating gut microbiota and alleviating ER stress.  相似文献   
142.
Five new peptaibols, longibramides A–E ( 1 – 5 ) with 11 amino acid residues, were isolated from a fungus Trichoderma longibrachiatum Rifai DMG-3-1-1, which was isolated from a mushroom Clitocybe nebularis (Batsch) P. Kumm collected from coniferous forest in the subboreal area of northeast China. The structures of longibramides A–E were determined by their spectroscopic data (NMR and MS-MS spectra), their absolute configurations were determined by X-ray diffractions and Marfey's analyses. The X-ray diffractions of longibramides A, B, and the similar CD spectra of A–E showed that they all had α-helix conformations. Longibramides B and E showed moderate cytotoxicities against BV2 and MCF-7 cells and also showed some inhibitory effects against methicillin-resistant Staphylococcus aureus MRSA T144. L-trans-Hyp was not commonly found in natural peptaibols, which was the 6th or 10th amino acid residue in longibramides C–E. The X-ray diffractions of longibramides A and B afforded the accuracy conformations of their secondary structures, which maybe help to interpret the structure-activity relationships of the family of peptaibols in the future.  相似文献   
143.
Hyperhomocysteinaemia (HHcy)-impaired endothelial dysfunction including endoplasmic reticulum (ER) stress plays a crucial role in atherogenesis. Hydrogen sulphide (H2S), a metabolic production of Hcy and gasotransmitter, exhibits preventing cardiovascular damages induced by HHcy by reducing ER stress, but the underlying mechanism is unclear. Here, we made an atherosclerosis with HHcy mice model by ApoE knockout mice and feeding Pagien diet and drinking L-methionine water. H2S donors NaHS and GYY4137 treatment lowered plaque area and ER stress in this model. Protein disulphide isomerase (PDI), a modulation protein folding key enzyme, was up-regulated in plaque and reduced by H2S treatment. In cultured human aortic endothelial cells, Hcy dose and time dependently elevated PDI expression, but inhibited its activity, and which were rescued by H2S. H2S and its endogenous generation key enzyme-cystathionine γ lyase induced a new post-translational modification-sulfhydration of PDI. Sulfhydrated PDI enhanced its activity, and two cysteine-terminal CXXC domain of PDI was identified by site mutation. HHcy lowered PDI sulfhydration association ER stress, and H2S rescued it but this effect was blocked by cysteine site mutation. Conclusively, we demonstrated that H2S sulfhydrated PDI and enhanced its activity, reducing HHcy-induced endothelial ER stress to attenuate atherosclerosis development.  相似文献   
144.
145.
中国建立国家公园的目的是保护自然生态系统的完整性和原真性, 促进生物多样性保护。国家公园的完整性和原真性评价是国家公园的布局规划、边界范围确定以及功能区划等研究的前提条件。为了评估国家公园自然生态系统完整性和原真性状态, 本文基于陆地自然生态系统的结构和功能, 通过指标筛选、专家咨询、指标量化和建立综合评价模型, 构建了陆地自然生态系统完整性与原真性的评价指标体系及其量化评价方法。该评价方法包括5个自然生态系统完整性指标、5个自然生态系统原真性指标和2个综合评价指标。以浙江省钱江源国家公园体制试点为例, 本文初步评估了其生态系统完整性与原真性状态, 并对评价结果进行了分级。按照本研究的评价方法, 钱江源国家公园体制试点的自然生态系统完整性评价结果为52.83%, 评价等级为较差; 自然生态系统原真性评价结果为87.06%, 评价等级为好。钱江源国家公园体制试点有待关注和提升的指标有保护区域完整性指数(27.00%)和旗舰种适宜生境完整性指数(53.04%)。最后, 本文结合研究区域评价结果对生态系统完整性和原真性领域应关注的问题进行了讨论。该自然生态系统完整性和原真性评价方法可提供一种评价指标覆盖较全面、数据易获取, 且评价结果易被决策者和管理者理解的评价思路。  相似文献   
146.
目的通过16S rRNA高通量基因测序方法对IgA肾病患者与健康人的肠道菌群进行比较。方法纳入生活于同一地区的40例IgA肾病患者与10例健康人,收集研究对象的新鲜粪便样本,提取粪便细菌总DNA,通过PCR扩增后上机测序,然后进行可操作分类单元聚类、物种分类分析及Alpha多样性分析、Beta多样性分析,最后比较两组之间的肠道菌群差异。结果与健康人相比,IgA肾病患者肠道菌群丰富度指数(Ace、Chao1)下降(u=2.308,P=0.033;u=2.259,P=0.039),多样性指数(Shannon、Simpson)升高(u=5.370,P0.001;u=4.601,P=0.007);相对丰度方面,IgA肾病患者的厚壁菌门、拟杆菌门、放线菌门细菌数量增加(t=2.301,P=0.037;t=6.729,P=0.005;t=5.285,P=0.006),而变形菌门细菌数量减少(t=4.138,P=0.009);拟杆菌属、链球菌属细菌数量增加(t=9.037,P=0.003;t=6.001,P=0.008),而unidentified_Enterobacteriaceae数量减少(t=2.198,P=0.033)。PCoA图提示两组肠道菌群有显著差异。LDA差异贡献分析发现两组之间共有15个物种存在显著差异,其中造成显著差异影响力最大的5个物种依次是γ-变形菌纲、unidentified_Enterobacteriaceae、肠杆菌科、肠杆菌目、变形菌门(t=9.930,P=0.002;t=2.198,P=0.033;t=2.604,P=0.015;t=2.393,P=0.021;t=4.138,P=0.009),它们刚好落在同一个进化树上,在IgA肾病组的相对丰度显著降低。结论 IgA肾病患者存在肠道菌群失调,显著减少的肠杆菌科的未知属可能是IgA肾病的特征菌,其对机体免疫的影响及在IgA肾病发生发展中的作用尚不清楚,进一步研究可能为IgA肾病的防治提供新的靶点。  相似文献   
147.
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   
148.
Jiao  Yan  Zhao  Dandan  Gao  Fuhua  Hu  Xiaoyan  Hu  Xinxin  Li  Mei  Cui  Ying  Wei  Xiaoqing  Xie  Ce  Zhao  Ying  Gao  Ying 《Journal of physiology and biochemistry》2021,77(1):47-61
Journal of Physiology and Biochemistry - Endothelial injury, which can cause endothelial inflammation and dysfunction, is an important mechanism for the development of atherosclerotic plaque. This...  相似文献   
149.
Gold nanoparticles are a kind of nanomaterials that have received great interest in field of biomedicine due to their electrical, mechanical, thermal, chemical and optical properties. With these great potentials came the consequence of their interaction with biological tissues and molecules which presents the possibility of toxicity. This paper aims to consolidate and bring forward the studies performed that evaluate the toxicological aspect of AuNPs which were categorized into in vivo and in vitro studies. Both indicate to some extent oxidative damage to tissues and cell lines used in vivo and in vitro respectively with the liver, spleen and kidney most affected. The outcome of these review showed small controversy but however, the primary toxicity and its extent is collectively determined by the characteristics, preparations and physicochemical properties of the NPs. Some studies have shown that AuNPs are not toxic, though many other studies contradict this statement. In order to have a holistic inference, more studies are required that will focus on characterization of NPs and changes of physical properties before and after treatment with biological media. So also, they should incorporate controlled experiment which includes supernatant control Since most studies dwell on citrate or CTAB-capped AuNPs, there is the need to evaluate the toxicity and pharmacokinetics of functionalized AuNPs with their surface composition which in turn affects their toxicity. Functionalizing the NPs surface with more peculiar ligands would however help regulate and detoxify the uptake of these NPs.  相似文献   
150.
Tumor infiltrating lymphocytes (TIL), especially T-cells, have both prognostic and therapeutic applications. The presence of CD8+ effector T-cells and the ratio of CD8+ cells to FOXP3+ regulatory T-cells have been used as biomarkers of disease prognosis to predict response to various immunotherapies. Blocking the interaction between inhibitory receptors on T-cells and their ligands with therapeutic antibodies including atezolizumab, nivolumab, pembrolizumab and tremelimumab increases the immune response against cancer cells and has shown significant improvement in clinical benefits and survival in several different tumor types. The improved clinical outcome is presumed to be associated with a higher tumor infiltration; therefore, it is thought that more accurate methods for measuring the amount of TIL could assist prognosis and predict treatment response. We have developed and validated quantitative immunohistochemistry (IHC) assays for CD3, CD8 and FOXP3 for immunophenotyping T-lymphocytes in tumor tissue. Various types of formalin fixed, paraffin embedded (FFPE) tumor tissues were immunolabeled with anti-CD3, anti-CD8 and anti-FOXP3 antibodies using an IHC autostainer. The tumor area of stained tissues, including the invasive margin of the tumor, was scored by a pathologist (visual scoring) and by computer-based quantitative image analysis. Two image analysis scores were obtained for the staining of each biomarker: the percent positive cells in the tumor area and positive cells/mm2 tumor area. Comparison of visual vs. image analysis scoring methods using regression analysis showed high correlation and indicated that quantitative image analysis can be used to score the number of positive cells in IHC stained slides. To demonstrate that the IHC assays produce consistent results in normal daily testing, we evaluated the specificity, sensitivity and reproducibility of the IHC assays using both visual and image analysis scoring methods. We found that CD3, CD8 and FOXP3 IHC assays met the fit-for-purpose analytical acceptance validation criteria and that they can be used to support clinical studies.  相似文献   
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