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61.
A FGLamide allatostatin neuropeptide mimic ( H17 ) is a potential insect growth regulator which inhibits the production of juvenile hormone by the corpora allata. To find more evidence to reveal the structure–activity relationships of the Phe3 residue in the C‐terminal conserved pentapeptide and search for novel analogs with high activity, a series of Phe3 residue‐modified analogs were designed and synthesized using H17 as the lead compound. Bioassay using juvenile hormone (JH) production by corpora allata of the cockroach Diploptera punctata indicated that analogs 4 , 11 , and 13 showed strong ability to inhibit JH production in vitro, with IC50 of 38.5, 22.5, and 26 nM, respectively. As well, the activity of analog 2 (IC50: 89.5 nM) proved roughly equivalent to that of H17 . Based on the primary structure–activity relationships of Phe3 residue, we suggest that for analogs containing six‐membered aromatic rings, removing the methylene group of Phe3 or an o‐halogen or p‐halogen‐substituted benzene ring could increase the ability to inhibit biosynthesis of JH. This study will be useful for the design of new allatostatin analogs for insect management. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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随着基因测序技术与核酸定量分析技术的发展,近年的大量研究表明,长链非编码RNA (long non-coding RNA,LncRNA) 通过多种途径调控基因表达,具有调节细胞功能的重要作用。LncRNA的异常表达与肿瘤发生发展之间的联系被广泛关注。其中,关于LncRNA与3种最常见的性激素依赖性肿瘤乳腺癌、子宫内膜癌和前列腺癌的研究,揭示其在肿瘤细胞或组织中扮演着类似于原癌基因或抑癌基因的双重角色。并通过多种调控机制,参与癌细胞的侵袭、增殖、转移等过程。因性激素受体分布的特异性,使得与之相关的多种LncRNA的表达也具有较高的特异性。本文总结LncRNA与乳腺癌、子宫内膜癌和前列腺癌的相关研究进展,包括涉及到的LncRNA种类、表达差异、作用机制及作为生物标志物或治疗靶点的可行性评价。  相似文献   
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L Yan  A Wang  L Chen  W Shang  M Li  Y Zhao 《Gene》2012,506(2):350-354
The present study investigated the expression of the apoptosis-related genes fas-associated via death domain (FADD) and Bcl-2 in the endometrium during the window of implantation in polycystic ovary syndrome (PCOS) patients. The aim was to explore the role of cell apoptosis in endometrial receptivity during this period. The subjects were divided into experimental and control group. The experimental group comprised 12 infertile women with PCOS, and the control group comprised 12 women who were infertile because of tubal pathological factors but had normal menstrual cycles. Endometria were collected by biopsy 7d after ovulation. Six samples from each group were randomly selected and subjected to gene chip analyses. The expression of endometrial FADD and Bcl-2 was determined by immunohistochemistry, and cell apoptosis was detected by the TUNEL method. Compared with the control group, 194 differentially expressed genes were found in the PCOS group, 102 of which were upregulated and 92 were downregulated. The differentially expressed genes were divided into 15 types according to function. Among the nine genes related to cell apoptosis, five (including Bcl-2) were upregulated and four were downregulated (including FADD). Bcl-2 expression during the window of implantation in the PCOS group increased compared with the control group, showing a significant difference (P<0.05). FADD expression in the PCOS group notably decreased compared with that in the control group, which also showed a significant difference (P<0.05). Cell apoptosis analysis showed a significant difference between the average apoptotic indices in the PCOS and control groups (P<0.05). Significant differences were observed between the endometrial gene expression in the PCOS and control groups. The decrease in cell apoptosis during the window of implantation in PCOS patients may be one of the causes of the reduced endometrial receptivity.  相似文献   
65.
Digitalis-like compounds (DLC) are a family of steroid hormones synthesized in and released from the adrenal gland. DLC, the structure of which resembles that of plant cardiac glycosides, bind to and inhibit the activity of the ubiquitous cell surface enzyme Na(+), K(+)-ATPase. However, there is a large body of evidence suggesting that the regulation of ion transport by Na(+), K(+)-ATPase is not the only physiological role of DLC. The binding of DLC to Na(+), K(+)-ATPase induces the activation of various signal transduction cascades that activate changes in intracellular Ca(++) homeostasis, and in specific gene expression. These, in turn, stimulate endocytosis and affect cell growth and proliferation. At the systemic level, DLC were shown to be involved in the regulation of major physiological parameters including water and salt homeostasis, cardiac contractility and rhythm, systemic blood pressure and behavior. Furthermore, the DLC system has been implicated in several pathological conditions, including cardiac arrhythmias, hypertension, cancer and depressive disorders. This review evaluates the evidence for the different aspects of DLC action and delineates open questions in the field.  相似文献   
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Two plasmids containing rat thyroglobulin cDNA sequences have been constructed and characterized. A plasmid with a 500-bp insert (pRT6) was isolated and identified as thyroglobulin-specific on the basis of the tissue specificity of the inserted sequence and of its ability to retain thyroglobulin mRNA on a nitrocellulose filter. The cDNA insert in pRT6 was subsequently used to screen a rat thyroid cDNA library constructed with large cDNA. A plasmid was found containing a 1700-bp insert. The polarity and the fidelity of the insert is demonstrated by S1 mapping.  相似文献   
68.
摘要 目的:研究血必净注射液联合比阿培南对重症肺炎患者肺功能的影响。方法:选择2017年1月~2019年12月我院的103例重症肺炎患者,随机分为两组。对照组静脉滴注比阿培南0.3 g ,每 8 h给药1次;观察组联合静脉滴注血必净50 mL,每天两次。检测两组的炎症因子:白介素-1(Interleukin-1, IL-1)、肿瘤坏死因子-α(Tumor necrosis factor-α, TNF-α)和IL-6水平,应激激素:皮质醇(Cortisol, Cor)、人血管紧张素Ⅰ(Human angiotensin I, AngⅠ)、去甲肾上腺素(Noradrenaline, NE)和人血管紧张素Ⅱ(Human angiotensinⅡ, AngⅡ)水平,肺功能:第一秒最大呼气量(Maximum expiratory volume in the first second, FEV1)、FEV1%pred、用力肺活量(Forced vital capacity, FVC)。结果:观察组的有效率明显高于对照组(P<0.05)。治疗后,两组的血清IL-1、TNF-α、IL-6、Cor、AngⅠ、NE和AngⅡ水平水平均明显降低,FEV1、FEV1%pred和FEV1/FVC明显升高(P<0.05),且观察组的上述指标明显优于对照组(P<0.05)。结论:血必净注射液联合比阿培南对重症肺炎有显著的疗效,不但能明显改善肺功能,还能有效抑制患者的应激反应和炎症反应,值得推广。  相似文献   
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Pyriforms are ovarian follicle nurse cells that undergo apoptosis at the end of previtellogenesis and are completely eliminated by the epithelium. This event is accompanied by the active transfer of organelles and macromolecules to the oocyte via an intercellular bridge. Since it would be a nonsense for damaged mitochondria to reach the oocyte, we have postulated that pyriform cells have adapted their apoptotic machinery to prevent mitochondrial degradation. To verify this hypothesis, we have studied mitochondrial morphology and functionality during follicle cell regression. Cytological and biochemical evidence indicates that mitochondria in pyriforms maintain their size, organization and membrane potential. This clearly indicates that they are not involved in apoptosis signalling/progression. This block would favour both the oocyte, by increasing the pool of organelles available from follicle cells, and also the regressing pyriforms, by maintaining the energy resources required for completion of their nurse function. The block is probably attributable to an over-expression of Bcl-2 and might be carried out by sequestering cytochrome c inside the organelles. As demonstrated by in vitro experiments, the mitochondrial apoptosis pathway can be activated by stress induction, such as serum deprivation, but not following physiological pro-apoptotic signalling, such as treatment with gonadotrophin-releasing hormone. These studies were supported by a grant from the MIUR (PRIN project: Molecular responses of embryonic, differentiated and tumoral cells exposed to cadmium intoxication).  相似文献   
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