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101.
102.
Symbiotic microbes play a crucial role in regulating parasite–host interactions; however, the role of bacterial associates in parasite–host interactions requires elucidation. In this study, we showed that, instead of introducing numerous symbiotic bacteria, dispersal of 4th-stage juvenile (JIV) pinewood nematodes (PWNs), Bursaphelenchus xylophilus, only introduced few bacteria to its vector beetle, Monochamus alternatus (Ma). JIV showed weak binding ability to five dominant bacteria species isolated from the beetles’ pupal chamber. This was especially the case for binding to the opportunistic pathogenic species Serratia marcescens; the nematodes’ bacteria binding ability at this critical stage when it infiltrates Ma for dispersal was much weaker compared with Caenorhabditis elegans, Diplogasteroides asiaticus, and propagative-stage PWN. The associated bacterium S. marcescens, which was isolated from the beetles’ pupal chambers, was unfavorable to Ma, because it caused a higher mortality rate upon injection into tracheae. In addition, S. marcescens in the tracheae caused more immune effector disorders compared with PWN alone. Ma_Galectin2 (MaGal2), a pattern-recognition receptor, was up-regulated following PWN loading. Recombinant MaGal2 protein formed aggregates with five dominant associated bacteria in vitro. Moreover, MaGal2 knockdown beetles had up-regulated prophenoloxidase gene expression, increased phenoloxidase activity, and decreased PWN loading. Our study revealed a previously unknown strategy for immune evasion of this plant pathogen inside its vector, and provides novel insights into the role of bacteria in parasite–host interactions.  相似文献   
103.
Autologous adipose tissue is an ideal soft tissue filling material, and its biocompatibility is better than that of artificial tissue substitutes, foreign bodies and heterogeneous materials. Although autologous fat transplantation has many advantages, the low retention rate of adipose tissue limits its clinical application. Here, we identified a secretory glycoprotein, leucine‐rich‐alpha‐2‐glycoprotein 1 (LRG‐1), that could promote fat graft survival through RAB31‐mediated inhibition of hypoxia‐induced apoptosis. We showed that LRG‐1 injection significantly increased the maintenance of fat volume and weight compared with the control. In addition, higher fat integrity, more viable adipocytes and fewer apoptotic cells were observed in the LRG‐1‐treated groups. Furthermore, we discovered that LRG‐1 could reduce the ADSC apoptosis induced by hypoxic conditions. The mechanism underlying the LRG‐1‐mediated suppression of the ADSC apoptosis induced by hypoxia was mediated by the upregulation of RAB31 expression. Using LRG‐1 for fat grafts may prove to be clinically successful for increasing the retention rate of transplanted fat.  相似文献   
104.
105.
孙谷畴 《生态学报》1988,8(4):379-380
广东鼎湖山自然保护区的亚热带季风常绿阔叶林,是我国季风亚热带具典型地带性植被类型。目前,除了保持它的原始林外,还有部分植被因人为活动而受破坏,代之以次生林。原始林内植被的覆盖造成的微环境是一个趋于平衡的生态系统。植物类型与植被环境的变化,改变了植物与昆虫已建立的固定关系,使昆虫栖息环境、食物数量和适食性都发生了变化。对两种林地植物受虫害的研究,有助于阐明植被改变后的生态后果。  相似文献   
106.
To explore the role of gut microbiota in Graves’ disease (GD) and Hashimoto’s thyroiditis (HT). Seventy fecal samples were collected, including 27 patients with GD, 27 with HT, and 16 samples from healthy volunteers. Chemiluminescence was used to detect thyroid function and autoantibodies (FT3, FT4, TSH, TRAb, TGAb, and TPOAb); thyroid ultrasound and 16S sequencing were used to analyze the bacteria in fecal samples; KEGG (Kyoto Encyclopedia of Genes and Genomes) and COG (Clusters of Orthologous Groups) were used to analyze the functional prediction and pathogenesis. The overall structure of gut microbiota in the GD and HT groups was significantly different from the healthy control group. Proteobacteria and Actinobacteria contents were the highest in the HT group. Compared to the control group, the GD and HT groups had a higher abundance of Erysipelotrichia, Cyanobacteria, and Ruminococcus_2 and lower levels of Bacillaceae and Megamonas. Further analysis of KEGG found that the “ABC transporter” metabolic pathway was highly correlated with the occurrence of GD and HT. COG analysis showed that the GD and HT groups were enriched in carbohydrate transport and metabolism compared to the healthy control group but not in amino acid transport and metabolism. Our data suggested that Bacillus, Blautia, and Ornithinimicrobium could be used as potential markers to distinguish GD and HT from the healthy population and that “ABC transporter” metabolic pathway may be involved in the pathogenesis of GD and HT.  相似文献   
107.
溶栓剂DSPAα1正处于治疗急性缺血性中风的III期临床研究,临床结果显示DSPAα1具有良好的药理学和安全特性。将DSPAα1基因序列按照毕赤酵母偏好密码子进行优化,并在毕赤酵母菌株GS115和KM71中进行表达,同时利用定点突变对糖基化侧链进行缺失,考察糖基侧链对毕赤酵母表达DSPAα1的影响。结果表明,野生型DSPAα1在GS115和KM71中均获得高表达,在摇瓶发酵条件下,表达量分别为70mg/L和105mg/L;利用SDS-PAGE对DSPAα1三种突变体(N117Q、N362Q和N117Q/N362Q)进行分析,与野生型蛋白质相比较,3种突变体的表达水平显著下降,同时纤溶平板测活数据显示,纯化后的突变体N117Q和N362Q比活性均低于野生型蛋白质的25%。这表明,N-型糖链(N117和N362)对毕赤酵母表达的DSPAα1分泌和酶活性具有重要作用。  相似文献   
108.
为了科学、定量地评价污水土地处理生态工程的综合效益,运用层次分析法(AHP),提出了评价指标体系、指标权重和综合效益计算方法.应用此方法对霍林河森林型慢速渗滤土地处理工程的综合效益进行了分析与评价.结果表明,霍林河森林型慢速渗滤土地处理工程的综合效益值CE=0.64,属于中级生态经济系统,而且具有良好的环境效益和社会效益  相似文献   
109.
Helicobacter pylori (H pylori) is known as one of the most common infectious pathogens, with high infection and recurrence rates worldwide. The prevalence of H pylori is up to 90% in developing countries, while the annual recurrence rate is much higher than that in developed countries. Recurrence can occur either by recrudescence or reinfection. Compared with reinfection, the time window for recrudescence is generally shorter, followed by the recurrence of H pylori–associated diseases in the short‐term. Many factors are involved in the H pylori reinfection, such as the prevalence of H pylori infection, living conditions and economic development, health conditions and so forth. Previous studies focused less on H pylori recrudescence. Therefore, the influencing factors for H pylori recrudescence needed further exploration. This study reviewed the recrudescence of H pylori infection and its influencing factors.  相似文献   
110.
本项研究观察了替硝唑对类杆菌,经腹腔感染小鼠的体内保护作用。结果显示替硝唑对脆弱类杆菌和产黑色素类杆菌感染的小鼠,均具有良好的保护作用,两株菌感染的半数有效剂量(ED50)分别为11.15mg/kg和13.04mg/kg。与甲硝唑相比,两者无显著性差异。  相似文献   
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