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51.
Renal cell carcinoma (RCC) is one of the most common malignancies in the urinary system. Due to the lack of early symptoms, diagnosis of RCC usually occurs at late stages or after cancer metastasis leading to poor prognosis. Therefore, it is crucial to study early molecular mechanisms and biomarkers. Previous studies have suggested that microRNAs are involved in RCC initiation and development, making them a good candidate for early diagnosis and therapy. MiR146b-5P plays important roles in the progression of multiple cancers including thyroid cancer, pancreatic cancer, cervical cancer. However, it is not clear whether and how miR146b-5P is involved in RCC. In this study, we aimed to investigate the function of miR146b-5P in RCC. We examined the expression levels of miR146b-5p in renal cancer tissue and cell lines. We also explored the effects of blocking miR146b-5p in renal tumor growth and inflammatory signaling. Finally, we determined if miR146b-5p regulates tumorigenesis through TRAF6. We found that miR146b-5p levels were significantly increased in renal cancer tissue and renal cancer cells. Blocking miR146b-5p suppressed renal tumor growth and enhanced inflammatory response through increased TRAF6 expression. These effects were eliminated in TRAF6 knockout mice. Our results suggest that enhanced miR146b-5p expression may be a biomarker for RCC and modulating miR146b-5p and TRAF6 levels represent a potential therapeutic strategy for RCC.  相似文献   
52.
摘要:【目的】本研究通过百日咳杆菌黏附素(PRN)基因的分段克隆表达及其在BALB/c小鼠的主动和被动免疫保护试验筛选PRN中的保护性抗原肽。【方法和结果】利用大肠杆菌进行PRN的完整蛋白、N端和C端多肽及其RI和RII区域多肽(双拷贝)的表达,命名为GST-PRN、GST-PN、GST-PC、GST-2PRI和GST-2PRII。Western blot检测证实5种表达产物均具有良好的反应原性。在主动免疫保护试验中,5种表达产物均能诱导小鼠产生较高的PRN抗体水平;当使用3 LD50的支气管败血波氏杆菌  相似文献   
53.
Gram-negative bacterial pathogens belonging to the Pasteurellaceae, Moraxellaceae, and Neisseriaceae families rely on an iron acquisition system that acquires iron directly from host transferrin (Tf). The process is mediated by a surface receptor composed of transferrin-binding proteins A and B (TbpA and TbpB). TbpA is an integral outer membrane protein that functions as a gated channel for the passage of iron into the periplasm. TbpB is a surface-exposed lipoprotein that facilitates the iron uptake process. In this study, we demonstrate that the region encompassing amino acids 7-40 of Actinobacillus pleuropneumoniae TbpB is required for forming a complex with TbpA and that the formation of the complex requires the presence of porcine Tf. These results are consistent with a model in which TbpB is responsible for the initial capture of iron-loaded Tf and subsequently interacts with TbpA through the anchor peptide. We propose that TonB binding to TbpA initiates the formation of the TbpB-TbpA complex and transfer of Tf to TbpA.  相似文献   
54.
Sun W  Xing B  Sun Y  Du X  Lu M  Hao C  Lu Z  Mi W  Wu S  Wei H  Gao X  Zhu Y  Jiang Y  Qian X  He F 《Molecular & cellular proteomics : MCP》2007,6(10):1798-1808
Hepatocellular carcinoma (HCC) is a highly malignant tumor, and chronic infection with hepatitis B virus is one of its major risk factors. To identify the proteins involved in HCC carcinogenesis, we used two-dimensional fluorescence DIGE to study the differentially expressed proteins in tumor and adjacent nontumor tissue samples. Samples from 12 hepatitis B virus-associated HCC patients were analyzed. A total of 61 spots were significantly up-regulated (ratio >/= 2, p 相似文献   
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56.
Acidophilic microorganisms involved in uranium bioleaching are usually suppressed by dissolved fluoride ions, eventually leading to reduced leaching efficiency. However, little is known about the regulation mechanisms of microbial resistance to fluoride. In this study, the resistance of Acidithiobacillus ferrooxidans ATCC 23270 to fluoride was investigated by detecting bacterial growth fluctuations and ferrous or sulfur oxidation. To explore the regulation mechanism, a whole genome microarray was used to profile the genome-wide expression. The fluoride tolerance of A. ferrooxidans cultured in the presence of FeSO4 was better than that cultured with the S0 substrate. The differentially expressed gene categories closely related to fluoride tolerance included those involved in energy metabolism, cellular processes, protein synthesis, transport, the cell envelope, and binding proteins. This study highlights that the cellular ferrous oxidation ability was enhanced at the lower fluoride concentrations. An overview of the cellular regulation mechanisms of extremophiles to fluoride resistance is discussed.  相似文献   
57.
We reported the design of fusion inhibitors with improved activity using a multivalent inhibitor design strategy. First, we chose C29 as the template sequence, which is a 29-mer peptide derived from HIV-1 gp41 CHR domain and has anti-HIV activity of IC50 118 nM in a cell–cell fusion assay. We optimized the crosslink sites and linkers of the template peptide. We found that N-terminal crosslink caused activity improvement based on the multivalent co-operative effect. Especially, the IC50 of peptide (CAcaC29)2 was improved from 49.02 (monomeric form) to 5.71 nM. Compared with long peptides, short peptides may be more suitable to analyze the co-operative effect. So we selected a shorter peptide C22 to synthesize the bivalent inhibitors. Due its weak helicity, no co-operative effect appeared. Therefore, we chose SC22EK, which were introduced salt bridges to consolidate the helicity based on the natural sequence C22. The cross-linked (CAcaSC22EK)2 was four times more potent than the monomer SC22EK in anti-HIV activity, with an IC50 value of 4.92 nM close to the high active peptide fusion inhibitor C34. The strategy used in this study may be used to design new fusion inhibitors to interfere similar processes.  相似文献   
58.
Meng  Xue  Mu  Fangfang  Zhang  Zeyu  Wu  Xinru  Gao  Tiantian  Zhao  Fenglan  Xue  Jianping  Duan  Yongbo  Zhang  Haijun 《Plant Cell, Tissue and Organ Culture》2021,146(3):473-482
Plant Cell, Tissue and Organ Culture (PCTOC) - Vitex negundo L. var. cannabifolia (Sieb. et Zucc.) Hand.-Mazz. is an important medicinal plant rich in bioactive compounds. In vitro tissue culture...  相似文献   
59.
呼吸系统感染发病率高,早期明确感染的病原体是提高治愈率、降低死亡率的关键.目前病原体培养仍是临床病原学诊断的主要方式,但其敏感性低、耗时较长,不利于早期诊断和治疗.宏基因组学测序技术具有覆盖病原体广泛、快速、无偏倚、无需特异性扩增的优势,在鉴定罕见、混合感染、免疫抑制患者感染和常规检测方法难以检测到病原体的诊断中有较高...  相似文献   
60.
Gao C  Che LW  Chen J  Xu XJ  Chi ZQ 《Cell research》2003,13(1):29-34
The present study was designed to determine the changes of phosphorylation of cAMP-response element binding protein(CREB)in hippocampus induced by ohmefentanyl stereoisomers(F9202 and F9204) in conditioned place preference(CPP)paradigm.The results showed that mice receiving F9202 and F9204 displayed obvious CPP.They could all significantly stimulate CREB phosphorylation and maintained for a long time without affecting total CREB protein levels.The effect of F9204 was similar to morphine which effect was more potent and longer than F9202.We also examined the effects of ketamine,a noncompetitive N-mthyl-D-asartate receptor(NR)antagonist,on morphine-,F9202-and F9204-induced CPP and phosphorylation of CREB in hippocampus.Ketamine could suppress not only the place preference but also the phosphorylation of CREB produced by morphine,F9202 and F9204.These findings suggest that alterations in the phosphorylation of CREB be relevant to opiates signaling and the development of opiates dependence.NR antagonists may interfere with opiates dependence and may have potential therapeutic implications.  相似文献   
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