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221.
The objective of this study was to analyze human fecal Lactobacillus community and its relationship with rheumatoid arthritis. Samples taken from rheumatoid arthritis (RA) patients and healthy individuals were analyzed by quantitative real-time PCR. Bacterial DNA was extracted from feces, and amplicons of the Lactobacillus-specific regions of 16S rRNA were analyzed by denaturing gradient gel electrophoresis. The richness, Shannon-Wiener index, and evenness of gut microbiota of both groups were analyzed to compare fecal Lactobacillus community structures. Results of this study demonstrated that fecal microbiota of RA patients contained significantly more Lactobacillus (10.62 ± 1.72 copies/g) than the control group (8.93 ± 1.60 copies/g). Significant increases were observed in RA patients in terms of the richness, Shannon-Wiener, and evenness measures, indicating more bacterial species, and increased bacterial diversity and abundance. These results suggest a potential relationship between Lactobacillus communities and the development and progression of rheumatoid arthritis. 相似文献
222.
A process for high level production of rapamycin by Streptomyces hygroscopicus using statistical designs and feeding strategy was developed. The amino acids (i.e. Lys, Tyr, and Gln) for precursor supply were screened out in the initial phase of fermentation. The optimum levels determined with Box-Behnken design were Lys 20, Tyr 4, and Gln 3 g/l. In the rapamycin biosynthesis phase, the important component, ammonium sulphate, was also identified. A novel two-stage feeding strategy was developed successfully to increase the flux of rapamycin biosynthesis, in which the optimized amino acid components were fed in the initial phase of fermentation, and then switched to feed 2 g/l ammonium sulphate at 72 h. The maximal rapamycin production reached 860.6 mg/l in a 7 l fermentor, which was 182 % higher than that of the control. This was the first report to integrate precursor engineering and cell physiological regulation methods to optimize rapamycin production. 相似文献
223.
Zou Keyuan 《Ocean Development & International Law》2013,44(1):69-93
The United States is the sole superpower in the contemporary world and its role in the development of the law of the sea cannot be ignored. Although having not yet acceded to the U.N. Convention on the Law of the Sea, the United States has contributed to the development of the international law of the sea in numerous ways, including responding to the so-called excessive maritime claims in East Asia and creating new rules of maritime enforcement. This article assesses this recent U.S. practice. 相似文献
224.
Yanmei Zou Shuo Yao Xiuqiong Chen Dian Liu Jianhua Wang Xun Yuan Jie Rao Huihua Xiong Shiying Yu Xianglin Yuan Feng Zhu Guohong Hu Yihua Wang Hua Xiong 《European journal of cell biology》2018,97(5):369-378
Object
This study aimed to investigate the role of lncRNA OIP5-AS1 in regulating radioresistance of colorectal cancer (CRC) cells.Methods
Microarray analysis was used to screen out lncRNAs differentially expressed in radio-resistant CRC cell lines. Expression levels of OIP5-AS1, miR-369-3p and DYRK1A in CRC cell lines were measured by qRT-PCR. Protein expression of DYRK1A was determined by western blot. The target relationships among OIP5-AS1, miR-369-3p and DYRK1A were validated by dual luciferase reporter assay. Impacts of OIP5-AS1 or DYRK1A on CRC cellular activity and apoptosis were investigated by MTT assay, clonogenic survival assay and flow cytometry to analyze OIP5-AS1 or DYRK1A’s effect on radioresistance of CRC cells.Results
LncRNA OIP5-AS1 and DYRK1A were down-regulated in radio-resistant CRC cell lines. OIP5-AS1 suppressed the expression of miR-369-3p, thus up-regulating DYRK1A, the downstream gene of miR-369-3p. OIP5-AS1 and DYRK1A impaired cell clonogenic survival and promoted cell apoptosis after irradiation, improving radiosensitivity of CRC cells.Conclusion
LncRNA OIP5-AS1 suppressed cell viability, promoted radio-induced apoptosis, and enhanced the radiosensitivity of CRC cells by regulating DYRK1A expression through miR-369-3p. 相似文献225.
Ling Zhou Hui Guo Quan Liao Jianping Zou Yi Le Ziling Fang Jianping Xiong Shanshan Huang Jun Deng Xiaojun Xiang 《Journal of cellular and molecular medicine》2023,27(20):3090-3106
Background
Malignant cell growth and chemoresistance, the main obstacles in treating gastrointestinal cancer (GIC), rely on the Hippo and p53 signalling pathways. However, the upstream regulatory mechanisms of these pathways remain complex and poorly understood.Methods
Immunohistochemistry (IHC), western blot and RT-qPCR were used to analyse the expression of RNF146, miR-3133 and key components of Hippo and p53 pathway. CCK-8, colony formation, drug sensitivity assays and murine xenograft models were used to investigate the effect of RNF146 and miR-3133 in GIC. Further exploration of the upstream regulatory mechanism was performed using bioinformatics analysis, dual-luciferase reporter gene, immunoprecipitation assays and bisulfite sequencing PCR (BSP).Results
Clinical samples, in vitro and in vivo experiments demonstrated that RNF146 exerts oncogenic effects in GIC by regulating the Hippo pathway. Bioinformatics analysis identified a novel miRNA, miR-3133, as an upstream regulatory factor of RNF146. fluorescence in situ hybridization and RT-qPCR assays revealed that miR-3133 was less expressed in gastrointestinal tumour tissues and was associated with adverse pathological features. Functional assays and animal models showed that miR-3133 promoted the proliferation and chemotherapy sensitivity of GIC cells. miR-3133 affected YAP1 protein expression by targeting RNF146, AGK and CUL4A, thus activating the Hippo pathway. miR-3133 inhibited p53 protein degradation and extended p53's half-life by targeting USP15, SPIN1. BSP experiments confirmed that miR-3133 promoter methylation is an important reason for its low expression.Conclusion
miR-3133 inhibits GIC progression by activating the Hippo and p53 signalling pathways via multi-targets, including RNF146, thereby providing prognostic factors and valuable potential therapeutic targets for GIC. 相似文献226.
227.
Zou BZ Takeda K Tonouchi A Akada S Fujita T 《Bioscience, biotechnology, and biochemistry》2003,67(10):2059-2067
The number of syntrophic butyrate-degrading bacteria in a flooded paddy field soil was 1.7 x 10(3) MPN/g dry soil. Butyrate was degraded to acetate and methane when paddy soils were incubated anaerobically with the addition of butyrate. However, butyrate degradation was completely suppressed by the addition of the specific inhibitor of methanogenesis, 2-bromoethanesulfonate (BES) to the soil. A hydrogen-using methanogen, strain TM-8, was isolated from flooded paddy field soil. Strain TM-8 was identified as Methanobacterium formicicum based on its physiology and phylogeny. Syntrophic butyrate-degrading bacteria were enumerated and isolated using strain TM-8. A syntrophic butyrate-degrading bacterium, strain TB-6, was isolated in coculture with strain TM-8 from paddy soil. The strain was Gram-negative, had curved rods, and grew on crotonate. Sulfate was not used as an electron acceptor. Strain TB-6 was closely related to S. wolfei subsp. wolfei. The relation between strain TB-6 and the members of Syntrophomonas are discussed. 相似文献
228.
Lan Liu Jaladanki N. Rao Tongtong Zou Lan Xiao Peng-Yuan Wang Douglas J. Turner Myriam Gorospe Jian-Ying Wang 《Molecular biology of the cell》2009,20(23):4885-4898
All mammalian cells depend on polyamines for normal growth and proliferation, but the exact roles of polyamines at the molecular level remain largely unknown. The RNA-binding protein HuR modulates the stability and translation of many target mRNAs. Here, we show that in rat intestinal epithelial cells (IECs), polyamines enhanced HuR association with the 3′-untranslated region of the c-Myc mRNA by increasing HuR phosphorylation by Chk2, in turn promoting c-Myc translation. Depletion of cellular polyamines inhibited Chk2 and reduced the affinity of HuR for c-Myc mRNA; these effects were completely reversed by addition of the polyamine putrescine or by Chk2 overexpression. In cells with high content of cellular polyamines, HuR silencing or Chk2 silencing reduced c-Myc translation and c-Myc expression levels. Our findings demonstrate that polyamines regulate c-Myc translation in IECs through HuR phosphorylation by Chk2 and provide new insight into the molecular functions of cellular polyamines. 相似文献
229.
230.
Intersubgenomic heterosis in seed yield potential observed in a new type of Brassica napus introgressed with partial Brassica
rapa genome 总被引:2,自引:0,他引:2
Qian W Chen X Fu D Zou J Meng J 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2005,110(7):1187-1194
This paper reports the observation on the intersubgenomic heterosis for seed yield among hybrids between natural Brassica napus (AnAnCnCn) and a new type of B. napus with introgressions of genomic components of Brassica rapa (ArAr). This B. napus was selected from the progeny of B. napus × B. rapa and (B. napus × B. rapa) × B. rapa based on extensive phenotypic and cytological observation. Among the 129 studied partial intersubgenomic hybrids, which were obtained by randomly crossing 13 lines of the new type of B. napus in F3 or BC1F3 to 27 cultivars of B. napus from different regions as tester lines, about 90% of combinations exceeded the yield of their respective tester lines, whereas about 75% and 25% of combinations surpassed two elite Chinese cultivars, respectively. This strong heterosis was further confirmed by reevaluating 2 out of the 129 combinations in a successive year and by surveying hybrids between 20 lines of the new type of B. napus in BC1F5 and its parental B. napus in two locations. Some DNA segments from B. rapa were identified with significant effects on seed yield and yield components of the new type of B. napus in BC1F5 and intersubgenomic hybrids in positive or negative direction. It seems that the genomic components introgressed from B. rapa contributed to improvement of seed yield of rapeseed. 相似文献