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101.
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
102.
103.
The effects on the fecundity and fertility of redbanded leafroller, Argyrotaenia velutinana (Walker), and obliquebanded leafroller,Choristoneura rosaceana (Harris), exposed as adults to surfaces treated with the ecdysone agonists tebufenozide (RH-5992) and methoxyfenozide (RH-2485) were examined. The first part of the study consisted of recently emerged moths being exposed to treated surfaces continuously throughout their lives (including mating and oviposition). Continuous exposure to tebufenozide- or methoxyfenozide-treated surfaces significantly reduced the mean number of eggs laid and the percent of eggs that hatched in both species. The second part of the study involved exposure of recently emerged virgin moths (by sex) to treated surfaces for 24 h, after which, the exposed moths were paired with a nontreated partner to mate and oviposit on nontreated surfaces. In this experiment, for A. velutinana, significant reductions in fecundity occurred only when the female was exposed to methoxyfenozide-treated surfaces. Significant reductions in A. velutinana egg fertility occurred with both male and female exposure in the methoxyfenozide treatments and only female exposure in the tebufenozide treatments. For C. rosaceana, significant reductions in fecundity occurred with both male and female exposure in the tebufenozide and methoxyfenozide treatments. Significant reductions in C. rosaceana egg fertility occurred with both male and female exposure in the tebufenozide treatments and only with female exposure in the methoxyfenozide treatments. 相似文献
104.
PNAS-4 is a novel pro-apoptotic protein activated during the early response to DNA damage; however, the molecular mechanisms and
pathways regulating PNAS-4 expression in tumors are not well understood. We hypothesized that PNAS-4 is a p53 down-stream target gene and designed this study. We searched online for putative p53-binding sites in the entire
PNAS-4 gene and did not find any corresponding information. In HCT116 colon cancer cells, after being transfected with small interfering
RNA to silence p53, the expressions of PNAS-4 and other known p53 target gene (Apaf1, Bax, Fas and Dr5) were determined by real-time PCR. We found that PNAS-4 was up-regulated while Apaf1, Bax, Fas and Dr5 were down-regulated. We then examined the expression of PNAS-4 and p53 mutation in colorectal cancer patients. PNAS-4 expressed both in colorectal cancers and normal tissues, but compared with paired control, PNAS-4 was up-regulated in cancers (P = 0.018). PNAS-4 overexpression ratios were correlated to the p53 mutant status (P = 0.001). The mean PNAS-4 expression levels of p53 mutant homozygote group and heterozygote group were higher than that of p53 wild type group (P = 0.013). The expression ratios of PNAS-4 (every sample in relative to its paired normal mucosa) were different between negative lymph node metastasis (66% up-regulated,
34% down-regulated) and positive metastasis (42% up-regulated, 58% down-regulated). Taken together, these findings suggested
that PNAS-4 was not a p53 target, but overexpression of PNAS-4 was correlated to p53 inactivity in colorectal cancer. 相似文献
105.
MiR‐616‐3p modulates cell proliferation and migration through targeting tissue factor pathway inhibitor 2 in preeclampsia 下载免费PDF全文
Yetao Xu Dan Wu Ziyan Jiang Yuanyuan Zhang Sailan Wang Zhonghua Ma Bingqing Hui Jing Wang Weiping Qian Zhiping Ge Lizhou Sun 《Cell proliferation》2018,51(5)
Objectives
Despite improvements in diagnosis and treatment, preeclampsia (PE) continues to pose a significant risk of maternal and foetal morbidity and mortality if not addressed promptly. An increasing number of studies have suggested that tissue factor pathway inhibitor 2 (TFPI2) acts as a suppressor gene, possibly inhibiting multiple serine proteases affecting cell proliferation and migration. It plays an essential role in the occurrence and development of PE, but the pathogenesis remains unclear.Materials and methods
In our research, we performed western blotting, immunohistochemistry and qPCR assays to investigate TFPI2 and miR‐616‐3p expression in preeclamptic placental tissues. Cell assays were performed in HTR‐8/SVneo and JEG3 cell lines. Cell proliferation and migration events were investigated by MTT, EdU and transwell assays. In conjunction with bioinformatics analysis, luciferase reporter assays were performed to elucidate the mechanism by which miR‐616‐3p binds to TFPI2 mRNA.Results
We established that TFPI2 protein levels were significantly upregulated in PE placental tissues. In addition, we found that miR‐616‐3p binds specifically to the 3′‐UTR region of TFPI2 mRNA. Furthermore, miR‐616‐3p knockdown or TFPI2 overexpression substantially impaired cell growth and migration, whereas miR‐616‐3p upregulation or TFPI2 knockdown stimulated cell proliferation and migration. This miR‐616‐3p / TFPI2 axis was also found to affect the epithelial‐mesenchymal transition process in PE.Conclusions
Our results demonstrated that TFPI2 plays a vital role in the progression of PE and might provide a prospective therapeutic strategy to mitigate the severity of the disorder.106.
In this study, we calculated the codon usage bias in H5N1 virus and performed a comparative analysis of synonymous codon usage patterns in H5N1 virus, five other evolutionary related influenza A viruses and a influenza B virus. Codon usage bias in H5N1 genome is a little slight, which is mainly determined by the base compositions on the third codon position. By comparing synonymous codon usage patterns in different viruses, we observed that the codon usage pattern of H5N1 virus is similar with other influenza A viruses, but not influenza B virus, and the synonymous codon usage in influenza A virus genes is phylogenetically conservative, but not strain-specific. Synonymous codon usage in genes encoded by different influenza A viruses is genus conservative. Compositional constraints could explain most of the variation of synonymous codon usage among these virus genes, while gene function is also correlated to synonymous codon usages to a certain extent. However, translational selection and gene length have no effect on the variations of synonymous codon usage in these virus genes. 相似文献
107.
水稻体细胞杂交研究进展 总被引:2,自引:0,他引:2
水稻是世界重要的粮食作物,全世界约有120个国家种植水稻。水稻的近缘或远缘种具有一些优良性状,如抗病、抗虫、抗逆等。将这些性状导入水稻,是科学家们所希望的,但因用普通杂交方法存在交配系统的不亲和性等难题而进展不大。随着组织培养技术的发展,特别是植物原生质体培养技术的日趋成熟,使得人类能够在细胞水平通过体细胞杂交方法实现遗传信息的重组。 相似文献
108.
AnxB1,a novel annexin previously isolated from Cysticercus cellulose,shows high thrombi affinity and anticoagulant activity in vivo.In order to investigate the relationship between structure and biological function,a predicted three-dimensional(3D)model of AnxB1 was generated by homology modeling.This model contains four homologous internal-domains and the Cα trace of domain Ⅰ,Ⅱ and IV shows high similarity.Based on the structure characterization,four sequence-deleted mutants were constructed and expressed as GST fusion proteins in E.coli.Two of the mutants,GST-M3 and GST-M4 reserved high anticoagulant activity(p<0.01 vs.GST).Furthermore,compared with the wild type GST-AnxB1,the immunogenicity of GST-M3 and GST-M4 was reduced significantly(p<0.01)and the molecular weight was lowered to 27 kD and 34 kD,respectively.These observations laid a solid foundation for further study on developing new thrombolytic agents with higher efficiency and lower side effect. 相似文献
109.
Tyrosinase Reaction and Subsequent Chitosan Adsorption for Selective Removal of a Contaminant from a Fermentation Recycle Stream 总被引:1,自引:0,他引:1 下载免费PDF全文
In the industrial production of penicillin V, the phenoxyacetate precursor is added to the fermentor to direct biosynthesis. When used for producing semisynthetic penicillins, the penicillin V is often hydrolyzed to 6-aminopenicillanic acid with the regeneration of the phenoxyacetate precursor. To reduce raw-material as well as waste-disposal costs, it is desirable to recycle the phenoxyacetate precursor. Unfortunately, the recycle stream is generally contaminated by the p-hydroxylated derivative of this precursor. We examined a two-step approach to eliminate this contaminant. In the first step the tyrosinase enzyme was used to selectively convert the p-hydroxyphenoxyacetate contaminant to a reactive intermediate—presumably its quinone. In the second step, the tyrosinase-generated reactive intermediate was allowed to react with and strongly bind to chitosan. In contrast, the phenoxyacetate precursor was neither oxidized by tyrosinase nor bound to chitosan. When concentrated phenoxyacetate solutions were tested, the combination of tyrosinase and chitosan effectively converted low levels of the p-hydroxyphenoxyacetate contaminant and removed its products from solution, while the concentration of the phenoxyacetate precursor was unaffected. 相似文献
110.