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931.
N6-methyladeosine (m6A) plays an important role in virus infection and replication. Bombyx mori nuclear polyhedrosis is caused by Bombyx mori nucleopolyhedrovirus (BmNPV) infection. Expression levels of m6A-modification-related genes after the infection of BmNPV were detected at first. Then, expression levels of BmNPV nucleocapsid protein gene VP39 and envelope fusion protein gene GP64 after knockdown of METTL3in vitro were quantified to identify the effect of m6A modification on BmNPV. BmNPV firstly infects the larval midgut in case of oral infection. Subsequently, to clarify the relationship between m6A modification and resistance of the silkworm to BmNPV, we detected the expression levels of m6A-modification-related genes invivo before and after infection of BmNPV. The results indicated that low METTL3 level hindered the proliferation of BmNPV to some extent, and silkworm strain with low METTL3 level showed stronger resistance against BmNPV. This study will accumulate new experimental data for elucidating the resistance mechanism of silkworm against BmNPV.  相似文献   
932.
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   
933.
Non-small cell lung cancer (NSCLC) is the main reason of cancer linked mortality and around 80% of cases diagnosed in advanced stage. Therefore current study designed to evaluate the deregulation of miRNA-194 and miRNA-192 in different body fluid of Non small cell lung cancer participants. Present study recruited newly diagnosed histopathologically confirmed. It was observed that the 40% NSCLC participants showed elevated miR-194 expression and 60% NSCLC participants showed reduced miR-194 expression in serum sample while in Bronchial wash, only 20% NSCLC participants showed elevated miR-194 expression while 80% showed reduced miR-194 expression (p = 0.003). It was found that the 54% NSCLC participants showed elevated miR-192 expression and 55% NSCLC participants showed reduced miR-192 expression in serum sample while In Bronchial wash sample, only 25% NSCLC participants showed high miR-192 expression while 75% showed low miR-192 expression (P = 0.0004). Expression of miR-194 was significantly associated with TNM stages (p < 0.0001, p < 0.0001), distant organ metastases (p < 0.0001, p < 0.0001), pathological grade (p = 0.0009, p = 0.0005) among serum sample and bronchial wash sample. Same observation was found with expression of miR-192 and it was significantly associated with TNM stages (p < 0.0001, p < 0.0001), distant organ metastases (p < 0.0001, p < 0.0001), pathological grade (p = 0.006, p = 0.001) among serum sample and bronchial wash sample. It was observed that the NSCLC participants who had high serum based miR-194 expression showed 22 months of overall median survival while low expression of serum based miR-194 expression showed 18 months of overall median survival. Present study suggests that decreased expression of miR-194 and miR-192 was significantly associated with different clinical features of NSCLC cases. However, significantly higher number of NSCLC cases showed low expression of miR-194 and miR-192 in bronchial lavage sample. Decreased poor overall survival was found to be associated with bronchial wash sample with respect to low miR-194 and miR-192 expression while NSCLC participants showed better overall survival with high miR-194 and miR-192 expression. This suggested decreased expression of miR-192 and miR-194 expression could be the potential prognostic marker among NSCLC participants.  相似文献   
934.
Global warming and eutrophication contribute to the worldwide increase in cyanobacterial blooms, and the level of cyanobacterial biomass is strongly associated with rises in methane emissions from surface lake waters. Hence, methane-metabolizing microorganisms may be important for modulating carbon flow in cyanobacterial blooms. Here, we surveyed methanogenic and methanotrophic communities associated with floating Microcystis aggregates in 10 lakes spanning four continents, through sequencing of 16S rRNA and functional marker genes. Methanogenic archaea (mainly Methanoregula and Methanosaeta) were detectable in 5 of the 10 lakes and constituted the majority (~50%–90%) of the archaeal community in these lakes. Three of the 10 lakes contained relatively more abundant methanotrophs than the other seven lakes, with the methanotrophic genera Methyloparacoccus, Crenothrix, and an uncultured species related to Methylobacter dominating and nearly exclusively found in each of those three lakes. These three are among the five lakes in which methanogens were observed. Operational taxonomic unit (OTU) richness and abundance of methanotrophs were strongly positively correlated with those of methanogens, suggesting that their activities may be coupled. These Microcystis-aggregate-associated methanotrophs may be responsible for a hitherto overlooked sink for methane in surface freshwaters, and their co-occurrence with methanogens sheds light on the methane cycle in cyanobacterial aggregates.  相似文献   
935.
目的:探讨2型糖尿病(T2DM)患者血糖波动与心律失常和下肢血管病变的关系,分析影响T2DM心律失常和下肢血管病变的因素。方法:选择2019年7月到2020年6月我院收治的82例T2DM患者,根据是否合并心律失常分为心律失常组28例和无心律失常组54例,根据是否合并下肢血管病变分为下肢血管病变组31例和无下肢血管病变组51例。所有患者均通过72 h监测血糖获得日内平均血糖波动幅度(MAGE)、日间血糖平均绝对差(MODD)、全天血糖标准差(SDBG)、全天血糖波动次数(NGE)。比较组间差异,分析影响T2DM患者心律失常和下肢血管病变的因素。结果:心律失常组MAGE、MODD、SDBG、NGE、糖化血红蛋白(HbA1c)、胰岛素抵抗指数(HOMA-IR)、T2DM病程、同型半胱氨酸(Hcy)、丙二醛(MDA)高于无心律失常组(P<0.05)。下肢血管病变组T2DM病程、Hcy、MDA、HOMA-IR、MAGE、MODD、SDBG、NGE均高于无下肢血管病变组(P<0.05)。Logistic回归分析结果显示MDA、HOMA-IR、MAGE、MODD是T2DM患者心律失常的危险因素(P<0.001),MAGE、MODD、SDBG是T2DM患者下肢血管病变的危险因素(P<0.001)。结论:T2DM患者血糖波动与心律失常和下肢血管病变均有关,血糖波动增加是T2DM心律失常和下肢血管病变的危险因素。  相似文献   
936.
Even with increasing interest in the ecological importance of intraspecific trait variation (ITV) for better understanding ecological processes, few studies have quantified ITV in seedlings and assessed constraints imposed by trade‐offs and correlations among individual‐level leaf traits. Estimating the amount and role of ITV in seedlings is important to understand tree recruitment and long‐term forest dynamics. We measured ten different size, economics, and whole leaf traits (lamina and petiole) for more than 2,800 seedlings (height ≥ 10 cm and diameter at breast height < 1 cm) in 283 seedling plots and then quantified the amount of ITV and trait correlations across two biological (intraspecific and interspecific) and spatial (within and among plots) scales. Finally, we explored the effects of trait variance and sample size on the strength of trait correlations. We found about 40% (6%–63%) variation in leaf‐level traits was explained by ITV across all traits. Lamina and petiole traits were correlated across biological and spatial scales, whereas leaf size traits (e.g., lamina area) were weakly correlated with economics traits (e.g., specific lamina area); lamina mass ratio was strongly related to the petiole length. Trait correlations varied among species, plots, and different scales but there was no evidence that the strength of trait relationships was stronger at broader than finer biological and spatial scales. While larger trait variance increased the strength of correlations, the sample size was the most important factor that was negatively related to the strength of trait correlations. Our results showed that a large amount of trait variation was explained by ITV, which highlighted the importance of considering ITV when using trait‐based approaches in seedling ecology. In addition, sample size was an important factor that influenced the strength of trait correlations, which suggests that comparing trait correlations across studies should consider the differences in sample size.  相似文献   
937.
高通量测序技术的发展提高了人们对微生物组的认识。宏基因组学技术因其全面和深入的分析功能被广泛应用于各种环境微生物组的研究中,尤其在阐明各种疾病与人体微生物组的关系中,宏基因组学技术具有重要作用。痤疮作为一种常见的皮肤疾病,严重影响人们皮肤美观度和心理健康。利用宏基因组学技术挖掘皮肤微生物与痤疮的关系,将有助于痤疮发病机理的研究和临床治疗方法的改进。通过介绍宏基因组学技术的发展背景、概述及其应用研究进展,探讨皮肤微生物与痤疮的关系,综述宏基因组学技术在痤疮研究中的应用现状,并总结目前宏基因组学技术在皮肤疾病研究中存在的问题,旨在为痤疮的宏基因组研究提供参考。  相似文献   
938.
N-glycosylation plays critical roles in protein secretion, sorting, stability, activity modulation, and interactions to other molecules in the eukaryotic organisms. Fungal β-1,4-mannanases have been widely used in the agri-food industry and contribute to the pathogenesis on plants. However, the information on N-glycosylation of a specific fungal carbohydrate-active enzyme (CAZyme) is currently limited. Herein, a cDNA was cloned from Aspergillus aculeatus QH1, displaying a full length of 1302 bp with an open reading frame of 1134 bp encoding for a GH5 subfamily 7 β-1, 4-mannanase, namely AacMan5_7A. The enzyme was purified and exhibited an optimal activity at pH 4.6 and 60 °C, hydrolyzing glucomannan and galactomannan, but not yeast mannan. AacMan5_7A is an N-glycosylated protein decorated with a high-mannose type glycan. Further through UPLC-ESI-MS/MS analysis, one of the four predicted N-glycosylation sites at N255 position was experimentally verified. The present study expands the information of N-glycosylation in fungal CAZymes, providing scientific bases for enhancing the production of fungal enzymes and their applications in food, feed, and plant biomass conversions.  相似文献   
939.
HLA haplotype analysis has important application value in human population genetics, anthropological research and HLA matching transplantation. Based on HLA-A, -B, -C, -DRB1 and -DQB1 genotyping data from 663 families including 663 leukemia patients and 991 related donors, the allele frequency (AF) and haplotype frequency (HF) of two-, three- and five-locus haplotype distribution patterns in the Chinese Han population were determined by family segregation. A total of 38 alleles at A locus, 75 alleles at B locus, 35 alleles at C locus, 53 alleles at DRB1 locus and 22 alleles at DQB1 locus were discovered in this population. The frequencies of these alleles were basically consistent with those of previous reports except for some tiny differences. The study found 11 A-C, 15 C-B, 4 B-DRB1 and 11 DRB1-DQB1 two-locus haplotypes with a frequency over 2%. The number of A-C-B and A-B-DRB1 three-locus haplotype with a frequency over 1% were 11 and 3 respectively. The most common HLA-A-C-B-DRB1-DQB1 haplotype (HF>1%) were A*3001-C*0602-B*1302-DR*0701-DQ*0202 (4.30%), A*0207-C*0102-B*4601-DR*0901-DQ*0303 (3.07%), A*3303-C*0302-B*5801-DR*0301-DQ*0201 (1.49%) and A*1101-C*0102-B*4601-DR*0901-DQ*0303 (1.01%). The results are helpful for finding matching donors for hematopoietic stem cell transplant patients and also contribute to transplant immunology, HLA-related diseases, research of human genetics and other fields.  相似文献   
940.
JAK/STAT plays an important role in cytokine signal transduction and it is potentially involved in the proinflammatory response during the early phase of severe acute pancreatitis (SAP). However, whether JAK2 activity is upregulated and whether JAK2 inhibition plays a role in the maintenance of pancreatic homeostasis during SAP is incompletely understood. Here we show that JAK2/STAT3 activity is highly elevated in SAP and blockade of JAK2 by AG-490 protects against SAP-induced pancreatic inflammation and injury. Gene expression and ELISA studies showed that JAK2 inhibition altered the cytokine profiles in both the circulation and pancreases. Further analysis revealed that JAK2 inhibition restored the level of cytokines critical for macrophage polarization towards M2 macrophage. Our findings suggest that pharmacological targeting at JAK2/STAT signalling may be an effective choice of therapeutic interventions against SAP.  相似文献   
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