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1.
以黑龙江省主栽红小豆品种珍珠红为供试材料,采用盆栽方式,分别在苗期、花荚期和鼓粒期喷施0(CK)、50、100和200μmol/L褪黑素,探讨外源褪黑素对红小豆生长、光合荧光特性和产量构成因素的影响。结果表明,与CK相比,50、100和200μmol/L褪黑素处理均能增加红小豆株高、叶面积和干物质积累,提高红小豆净光合速率、蒸腾速率、气孔导度、胞间CO2浓度、最大光化学效率和潜在光化学活性,且褪黑素浓度为100μmol/L时各指标提高幅度最大。在苗期、花荚期、鼓粒期喷施100μmol/L褪黑素处理的红小豆单株粒重分别为5.53、6.13和5.90g,与CK相比分别增加了6.3%、12.1%和9.5%。综上可知,红小豆花荚期喷施100μmol/L褪黑素增产效果最显著。  相似文献   
2.
胃肠道褪黑素主要是由肠嗜铬细胞分泌,具有一定昼夜节律性。褪黑素通过调控细胞因子或NF-κB等调控肠道微生物及其代谢,进而影响动物肠道微生物群体结构以及某些细菌的昼夜节律。本文主要对近几年胃肠道褪黑素的合成分泌及其生理功能、肠道微生物节律性以及褪黑素对肠道微生物的调控作用等研究进行综述,以期为胃肠道褪黑素与菌群之间调控关系的研究提供一定参考。  相似文献   
3.
近年来多种感染人或家畜的冠状病毒病轮番出现,给人类社会的经济和公共卫生安全带来很大危害。特别是在2019年底出现并在全球迅速蔓延的SARS-CoV-2,由此引发的新型冠状病毒肺炎(COVID-19)在2019年12月至2020年3月之间在全球范围内造成超过7万人死亡。冠状病毒感染宿主的第一步是识别宿主细胞膜受体分子并与之结合,随后启动入侵使病毒基因组进入宿主细胞内部。因此冠状病毒细胞受体的阐明对于了解病毒的宿主与组织嗜性具有重要意义,同时也有助于了解病毒的致病与传播机制以及新型抗病毒药物研发。本文介绍了近年来主要的冠状病毒受体的最新研究进展,包括血管紧张素2(the angiotensin converting enzyme 2,ACE2)、氨基肽酶N(aminopeptidase N,APN)、二肽酰肽酶4(dipeptyl peptidase 4,DPP4)、唾液酸(sialic acid,SA)和癌胚抗原相关细胞黏附分子1(carcinoembryonic antigen-related cell adhesion molecule 1,CEACAM1)等。  相似文献   
4.
AIM: To investigate the effects of astragaloside IV (AS-IV) on chemokine receptor 4 (CXCR4) and stromal cell-derived factor 1α (SDF-1α) in endothelial progenitor cells (EPCs) and its mechanism. METHODS: Rat bone marrow-derived EPCs were cultured in vitro. The proliferation, adhesion, migration, apoptosis and tube formation capacity of EPCs treated with AS-IV and AMD3100, a specific blocker of CXCR4, were observed. The effects of AS-IV on the expression of SDF-1α/CXCR4 at mRNA and protein levels and the protein level of p-CXCR4 in the EPCs were determined. RESULTS: AS-IV significantly enhanced the proliferation, adhesion, migration and tube formation abilities of EPCs, reduced the apoptosis of EPCs, and up-regulated the mRNA and protein expression of SDF-1α and CXCR4 and the p-CXCR4 protein level in the EPCs. On the other hand, AMD3100 blocked the up-regulating effect of AS-IV on the mRNA and protein expression of CXCR4 and the p-CXCR4 protein level in the EPCs, but did not affect the effect of AS-IV on the expression of SDF-1α. CONCLUSION: AS-IV might enhance the biological function of EPCs by regulating the expression of SDF-1α/CXCR in EPCs.  相似文献   
5.
AIM: To explore the effect of inositol 1, 4, 5-trisposphate receptor (IP3R) in luteinizing hormone-epidermal growth factor receptor (LH-EGFR)-induced oocyte meiotic resumption. METHODS: Models of mouse cumulus-oocyte complexs (COCs) culture and follicle culture in vitro were generated to study the effects of 2-aminoethyl diphenyl borate (2-APB) and heparin (IP3R specific inhibitors) on LH/EGF-induced oocyte meiotic resumption and EGF-induced cumulus cell expansion. Real-time PCR was used to detect the mRNA expression of cumulus expansion-related factors. The changes of the intracellular calcium level were monitored using Fluo 3-AM, and the cGMP level was measured by ELISA. RESULTS: The inhibitors of IP3R, 2-APB and heparin, dramatically reversed EGF-induced oocyte maturation (P<0.05) and decreased cGMP levels in COCs (P<0.05). In addition, 2-APB and heparin reversed EGF-induced cumulus expansion, and significantly inhibited EGF-induced cumulus expansion-related factor expression (P<0.05). The activation of IP3R increased intracellular calcium level, and the study found that 2-APB and heparin dramatically reversed EGF-induced elevation of calcium level in cumulus cells (P<0.05). Follicular culture in vitro showed that 2-APB and heparin significantly reversed the LH-induced oocyte maturation (P<0.05). CONCLUSION: LH-EGFR signaling pathway increases calcium level in cumulus cells through IP3R, resulting in meiotic resumption.  相似文献   
6.
ABSTRACT

The immunostimulatory and disease-resistance properties of Achyranthes aspera were evaluated in rohu (Labeo rohita) challenged with Aeromonas hydrophila. Experimental diets were enriched with leaves at 0.25% (D1) and 0.5% (D2) and seeds at 0.5% (D3); the control diet (D4) was without any enrichment. Rohu (2.02 ± 0.23 g) were cultured for 75 days and then challenged with bacteria. The highest average weight was observed in the D3 diet-fed fish. The cumulative mortality rates were 70%, 60%, 40%, and 30% in the D4, D1, D2, and D3 diets fed to rohu respectively. Enriched diets significantly increased myeloperoxidase, nitric oxide synthase, and serum lysozyme levels and decreased malondialdehyde and carbonyl protein content. Expressions of lysozyme C and lysozyme G were significantly (P < .05) higher in the D3 diet-fed fish. In the kidney, IL-1β and TLR 4 were up-regulated in enriched-diet-fed fish. Supplementation of seeds and leaves at 0.5% showed a positive impact in fish.  相似文献   
7.
Excessive stress response causes disability in social life. There are many diseases caused by stress, such as gastrointestinal motility disorders, depression, eating disorders, and cardiovascular diseases. Transient receptor potential (TRP) channels underlie non-selective cation currents and are downstream effectors of G protein-coupled receptors. Ca2+ influx is important for smooth muscle contraction, which is responsible for gastrointestinal motility. Little is known about the possible involvement of TRP channels in the gastrointestinal motility disorders due to stress. The purpose of this study was to measure the changes in gastrointestinal motility caused by stress and to elucidate the mechanism of these changes. The stress model used the water immersion restraint stress. Gastrointestinal motility, especially the ileum, was recorded responses to electric field stimulation (EFS) by isometric transducer. EFS-induced contraction was significantly reduced in the ileum of stressed mouse. Even under the conditions treated with atropine, EFS-induced contraction was significantly reduced in the ileum of stressed mouse. In addition, carbachol-induced, neurokinin A-induced, and substance P-induced contractions were all significantly reduced in the ileum of stressed mouse. Furthermore, the expression of TRPC3 was decreased in the ileum of stressed mouse. These results suggest that the gastrointestinal motility disorders due to stress is associated with specific non-selective cation channel.  相似文献   
8.
为研究非长绒期埋植外源褪黑激素对不同年龄内蒙古绒山羊产绒性能的影响,本试验选择2~6岁能繁母羊150只,每个年龄段根据产绒量和体重将母羊随机分为对照组和试验组,试验组于2014年4月30日和6月30日埋植2 mg/kg BW褪黑激素于耳部皮下。自埋植开始至试验结束(2015年4月底抓绒),逐月观察山羊绒生长情况,并于抓绒时采集绒样,分析埋植对山羊绒生长的影响。结果表明:与对照组相比,试验组所有年龄段山羊绒产量和绒长度均显著提高,绒细度显著降低(P<0.05),其中5岁埋植组山羊的产绒量提高幅度和细度下降幅度最大,分别达到28.75%、4.94%,6岁埋植组山羊绒长度增加幅度最大,为29.27%。综上,不同年龄内蒙古绒山羊埋植外源褪黑激素均有促进山羊绒生长和提高产量作用,但不同年龄绒山羊增产效果不一致,并且褪黑激素对于提高内蒙古绒山羊后期的生产力作用更大。  相似文献   
9.
10.
NMB/NMBR通过调节A型流感病毒(IAV/H1N1/PR8)感染诱导的细胞因子表达而参与抗IAV的先天性免疫反应。为探究其发挥抗IAV/H1N1感染的信号通路,本文用PR8和WSN毒株分别感染MLE-12细胞和小鼠,用NF-κB抑制剂BAY11-7028单独或联合NMB处理MLE-12细胞,小鼠后腿肌内注射NMB和NMBRA,采用RT-PCR和qRT-PCR分析NMBNMBRIL-6、IFN-α和NP基因表达变化,采用Western blot分析NMB、NMBR、P65/p-P65、IκBα和NP蛋白表达的变化。结果显示,BAY11-7028可促使PR8和WSN感染的MLE-12细胞中NMB、NMBRIL-6和IFN-α基因表达水平均下降和NP基因表达水平上升,并降低NMB、NMBR和p-P65蛋白表达水平和提升IκBα和NP蛋白表达水平。然而,NMB联合BAY 11-7028诱导PR8或WSN感染后的细胞中IL-6和NP表达出现极显著下降和IFN-α显著上升。此外,NMB抑制PR8和WSN感染的小鼠肺组织内p-P65和NP蛋白表达水平和促进IκBα蛋白表达水平;NMBRA联合NMB抵消NMB对PR8或WSN感染后的这些蛋白表达水平的调节作用。综上表明,NMB/NMBR通过调节PR8和WSN感染的MLE-12细胞和小鼠体内的NF-κB信号通路上P65蛋白磷酸化和IκBα的表达,进而影响下游细胞因子IL-6和IFN-α基因的表达,从而发挥抗IAV/H1N1感染的先天性免疫应答反应。  相似文献   
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