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971.
Protein arginylation by arginyl–transfer RNA protein transferase (ATE1) is emerging as a regulator protein function that is reminiscent of phosphorylation. For example, arginylation of β-actin has been found to regulate lamellipodial formation at the leading edge in fibroblasts. This finding suggests that similar functions of β-actin in other cell types may also require arginylation. Here, we have tested the hypothesis that ATE1 regulates the cytoskeletal dynamics essential for in vivo platelet adhesion and thrombus formation. To test this hypothesis, we generated conditional knockout mice specifically lacking ATE1 in their platelets and in their megakaryocytes and analyzed the role of arginylation during platelet activation. Surprisingly, rather than finding an impairment of the actin cytoskeleton structure and its rearrangement during platelet activation, we observed that the platelet-specific ATE1 knockout led to enhanced clot retraction and in vivo thrombus formation. This effect might be regulated by myosin II contractility since it was accompanied by enhanced phosphorylation of the myosin regulatory light chain on Ser19, which is an event that activates myosin in vivo. Furthermore, ATE1 and myosin co-immunoprecipitate from platelet lysates. This finding suggests that these proteins directly interact within platelets. These results provide the first evidence that arginylation is involved in phosphorylation-dependent protein regulation, and that arginylation affects myosin function in platelets during clot retraction.  相似文献   
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OBJECTIVE: To systematically investigate the safety of Xingxue Shuxuening injection(SXN) in preand post-marketing, and to ensure clinical drug safety.METHODS: Strict quality control in raw herb selection and production processes was adopted and pharmacology research on SXN was performed by the drug manufacturing company, Heilongjiang ZBD Pharmaceutical Co., Ltd. We systematically reviewed the safety literature of Xingxue SXN. Adverse drug reaction(ADR) data of the drug, extracted from Spontaneous Reporting System(SRS), and clinical characters based on 20 hospital information systems(HIS) in China, were analyzed. Large-scale prospective safety monitoring and Risk Minimization Action Plans(Risk MAPs) of XingxueSXN were carried out.RESULTS: The quality of SXN was stable and controllable when it was produced. Drug toxicology studies found no effect on rabbits with hemolytic or condensed, local stimulation and muscle stimulation, and no allergic reactions in guinea pigs. The ADRs of Xingxue SXN were dizziness, phlebitis,and vomiting based on SRS data. The injection did not conform to instructions in clinical practice when we analyzed HIS database, and patient's abnormal blood urea nitrogen levels may be related to the drug, when analyzed using the propensity score method. A nested case-control study was designed and performed to analyze the influencing factors of suspected allergic reactions to SXN. The study showed that patients with an allergy history were more prone to allergic reactions(P〈0.001),and some medicine combinations could cause allergic reactions.CONCLUSION: These studies have established a body of evidence on Xingxue SXN safety, and provide a good model for Chinese medicine injection for clinical safety. The Xingxue SXN production process and toxicology research indicate the safety of the injection. However, the use of the injection is not consistent with instructed clinical practice.Xingxue SXN causes ADRs perhaps from inappropriate usage or its  相似文献   
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ABSTRACT: BACKGROUND: Allergic skin inflammation such as atopic dermatitis (AD), which is characterized by pruritus and inflammation, is regulated partly through the activity of regulatory T cells (Tregs). Tregs play key roles in the immune response by preventing or suppressing the differentiation, proliferation and function of various immune cells, including CD4+ T cells. Recent studies report that fermentation has a tremendous capacity to transform chemical structures or create new substances, and the omega-3 polyunsaturated fatty acids (n-3 PUFAs) in fish oil can reduce inflammation in allergic patients. The beneficial effects of natural fish oil (NFO) have been described in many diseases, but the mechanism by which fermented fish oil (FFO) modulates the immune system and the allergic response is poorly understood. In this study, we produced FFO and tested its ability to suppress the allergic inflammatory response and to activate CD4+CD25+Foxp3+ Tregs. RESULTS: The ability of FFO and NFO to modulate the immune system was investigated using a mouse model of AD. Administration of FFO or NFO in the drinking water alleviated the allergic inflammation in the skin, and FFO was more effective than NFO. FFO treatment did increase the expression of the immune-suppressive cytokines TGF-beta and IL-10. In addition, ingestion of FFO increased Foxp3 expression and the number of CD4+CD25+Foxp3+ Tregs compared with NFO. CONCLUSIONS: These results suggest that the anti-allergic effect of FFO is associated with enrichment of CD4+CD25+Foxp3+ T cells at the inflamed sites and that FFO may be effective in treating the allergic symptoms of AD.  相似文献   
979.
目的 研究还原型谷胱甘肽对慢性阻塞性肺疾病(COPD)急性加重期患者氧化与抗氧化能力的影响.方法 检测20例健康成年人全血丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-PX)含量,并与72例COPD急性加重期患者治疗前的上述指标进行对应比较,发现COPD急性加重期的全血GSH-PX的活性比健康组低,而MDA的含量比健康...  相似文献   
980.
Previous studies have shown that rat epididymis-specific gene HongrES1 plays important roles in sperm capacitation and fertility. In this study, we cloned the mouse homologue gene by sequence alignment and RT-PCR methods and designated it as mHong1. The mHong1 gene is located on chromosome 12p14, spanning five exons. The cDNA sequence consists of 1257 nucleotides and encodes a 419 amino-acid protein with a predicted N-terminal signal peptide of 20 amino acids. The mHong1 mRNA shows similarity with HongrES1 in the expression patterns: (i) specific expression in epididymal tissue, especially in the cauda region; and (ii) androgen-dependence but testicular fluid factor independence. Its protein product shows 71% similarity with HongrES1 and contains a classical serpin domain as does HongrES1. A polyclonal antibody against mHong1 with high specificity and sensitivity was raised. Like HongrES1, the mHong1 protein shows a checker-board expression pattern in the epididymal epithelium and is secreted into the epididymal lumen. The mHong1 protein shows higher glycosylation than HongrES1. Although both of them are deposited onto the sperm head surface, mHong1 is localized to the equatorial segment, which is different from that of HongrES1. The mHong1 protein can be removed from the sperm membrane by high ionic strength and therefore can be classed as an extrinsic membrane protein. Collectively, we conclude that mHong1 is the homologue of HongrES1 and the present work paves the way for establishing animal models to elucidate the precise functions of HongrES1 and mHong1.  相似文献   
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