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81.
本文以甜高粱秸秆汁为主要的发酵原料,对热带假丝酵母SG-1在15-L罐上产单细胞蛋白(SCP)的分批补料发酵过程进行研究。首先对分批发酵模式下的菌体代谢过程变化进行研究。研究发现,接种后菌体快速进入繁殖阶段,但是总糖在12 h处于耗竭状态,使得菌体量和SCP产量过早的在18 h就达到峰值。基于此,在15-L罐上建立了热带假丝酵母SG-1产SCP的分批补料发酵模式。结果表明:菌体代谢因基质的补加而得到进一步的延续,放罐时(42 h)其菌体干重和SCP产量分别达19.86 g/L和9.93 g/L,显著高于分批发酵模式的10.45 g/L和4.70 g/L。 相似文献
82.
旨在研究褪黑素(melatonin,MT)对体外培养猪精原干细胞(spermatogonial stem cells,SSCs)的作用机制。本研究采集3头7日龄健康大白公猪睾丸,利用差速贴壁法获得SSCs。后经形态学观察、碱性磷酸酶染色、标记基因检测及免疫荧光染色鉴定后以SSCs作为试验材料,设置MT浓度梯度(0、50、250、500、1 000 μmol·mL-1)组处理SSCs,每组设3个重复(n=3),空白对照组加入0.1% DMSO处理,分别检测添加MT后猪SSCs的细胞活力、活性氧(reactive oxygen species,ROS)水平、谷胱甘肽(glutathione,GSH)含量及凋亡基因表达变化。结果显示:1)分离的克隆团细胞具有SSCs的生长特性,可被碱性磷酸酶染色并表达干细胞标志基因OCT4、SOX2和SSCs标志基因NANOG、PLZF、UCHL1;2)50 μmol·mL-1以上的MT在处理48 h后可显著提高SSCs的细胞活力(P<0.05);3) MT可显著降低猪SSCs内ROS水平(P<0.05),极显著增加细胞内GSH含量(P<0.01);4) MT可显著抑制猪SSCs内凋亡蛋白Bax和Caspase3的表达(P<0.05)。MT具有清除猪SSCs中的ROS,提高总GSH含量,抑制凋亡基因表达进而提高细胞活力的作用,可为养殖过程中提高公猪繁殖性能提供参考。 相似文献
83.
NPFFR1基因对鹅卵泡颗粒细胞激素分泌和细胞凋亡的影响研究 总被引:1,自引:1,他引:0
神经相关肽受体(RFamide-related peptide receptor,NPFFR1)是促性腺激素抑制激素的主要亲和受体,它在调控动物繁殖方面起着重要作用。为了解NPFFR1对鹅卵巢卵泡发育的作用,本研究以42周龄健康产蛋四川白鹅为试验材料(n=9),利用RT-qPCR法检测NPFFR1基因在等级前和等级卵泡颗粒细胞中的mRNA表达规律;在颗粒细胞中过表达NPFFR1基因,酶联免疫吸附法检测颗粒细胞上清液(n=9)中雌二醇(estradiol,E2)、孕酮(progesterone,P4)和抗缪勒管激素(anti-Mullerian hormone,AMH)的浓度变化,剩余贴壁细胞作一步法TUNEL检测细胞凋亡情况;转录组测序方法筛选大黄卵泡(8~10 mm)颗粒细胞过表达NPFFR1前后表达差异显著基因,并对差异表达基因进行功能聚类分析。结果显示,除F1等级外,其余等级卵泡颗粒细胞NPFFR1表达量均极显著高于等级前卵泡(P<0.01);过表达NPFFR1后,等级颗粒细胞上清液中的E2和等级前颗粒细胞上清液AMH的含量显著(P<0.05)降低,但孕酮P4含量变化不显著(P>0.05);转录组测序共筛选到267个差异表达基因(119个下调,148个上调),这些基因主要富集在生物节律过程、繁殖进程等生物学过程中;同时,与对照组相比,差异基因AMH显著下调表达(P<0.05),Clock(clock circadian regulator)、FOS(proto-oncogene,AP-1 trans-cription factor subunit)、Per(period circadian regulator)和ANTXR2(cell adhesion molecule 2)分别极显著(P<0.01)或显著(P<0.05)上调表达。上述试验结果提示,NPFFR1可从激素、细胞凋亡和生物节律等多个环节影响卵泡颗粒细胞,参与调控卵泡的时序等级发育。 相似文献
84.
旨在探究5-氮杂-2-脱氧胞苷(5-Aza-2’-deoxycytidine,5-Aza-dC)对牛成肌细胞的增殖和肌分化因子(myogenic differentiation 1,MyoD1)启动子甲基化以及mRNA表达的影响。本研究复苏了前期冻存的关岭牛成肌细胞,并进行培养,待其生长到对数生长期,再通过不同浓度的5-Aza-dC对牛成肌细胞进行处理,利用流式细胞仪检测细胞凋亡和周期;结合高通量检测方法检测MyoD1启动子甲基化水平,并利用qRT-PCR检测MyoD1及相关基因的表达水平。研究发现,0.1 μmol·L-15-Aza-dC为最适浓度,该浓度下细胞抗凋亡因子Bcl的表达极显著降低(P<0.01),促凋亡因子Bax的表达极显著提高(P<0.01),促凋亡因子Caspase-9的表达显著提高(P<0.05);周期因子Cyclin A2的表达显著提高(P<0.05),而细胞因子Cyclin B1、Cyclin D的表达无显著变化;检测空白组和试验组MyoD1启动子甲基化水平发现,试验组甲基化水平极显著低于空白组(P<0.01);而mRNA的表达水平极显著高于空白组(P<0.01)。5-Aza-dC能够通过改变Caspase-9、Bcl、Bax、Cyclin A2等基因的表达来调节关岭牛成肌细胞的增殖和凋亡,并能够有效降低MyoD1基因启动子的甲基化水平(P<0.01);极显著提高其mRNA的表达量(P<0.01)。低浓度的5-Aza-dC能通过促进细胞凋亡及调控关岭牛MyoD1的甲基化水平来调控MyoD1的表达;同时推测,MyoD1基因启动子的甲基化水平能够影响关岭牛成肌细胞的生长发育,可为遗传标记辅助关岭牛的改良提供理论参考。 相似文献
85.
86.
Rina Yamane Makoto Tanaka Nao Kikugawa Hideki Yasui Kenta Takei Miwa Harada Shinya Kaneda 《Journal of toxicologic pathology》2021,34(1):127
The pathological effects of copper deficiency (COD) are well known. However, the pathogenesis of cardiomyopathy resulting from COD remains unclear. In this study, aimed to elucidate the pathogenesis of COD-induced cardiomyopathy by examining the morphology of the cardiovascular system in copper-deficient rats using histopathology, immunohistochemistry, and scanning and transmission electron microscopy. Changes detected in the myocardium and interstitium were consistent with those reported for COD. Morphological changes included mesh-like changes in the capillary endothelial cells that appear to be a novel finding in COD-induced cardiomyopathy. These changes are hypothesized to result from abnormal vascular remodeling following damage to the basement membrane and due to the mechanical effects of myocardial contractions. Although cardiomyopathy may be associated with microcirculatory disorders arising from these lesions, further investigations are necessary to demonstrate a causal relationship between the pathogenesis of cardiomyopathy and the contribution of these lesions to disease progression. 相似文献
87.
88.
Xinpeng Yang Yue Feng Yang Li Dake Chen Xuanyan Xia Jialian Li Fenge Li 《Reproduction in domestic animals》2021,56(3):416-426
Sertoli cells are the only somatic cells in the seminiferous epithelium which directly contact with germ cells. Sertoli cells exhibit polarized alignment at the basal membrane of seminiferous tubules to maintain the microenvironment for growth and development of germ cells, and therefore play a crucial role in spermatogenesis. Androgens exert their action through androgen receptor (AR) and AR signalling in the testis is essential for maintenance of spermatogonial numbers, blood–testis barrier integrity, completion of meiosis, adhesion of spermatids and spermiation. In the present study, we demonstrated that AR gene could promote the proliferation of immature porcine Sertoli cells (ST cells) and the cell cycle procession, and accelerate the transition from G1 phase into S phase in ST cells. Meanwhile, miR-124a could affect the proliferation and cell cycle procession of ST cells by targeting 3′-UTR of AR gene. Furthermore, AR bound to the RNF4 via AR DNA-binding domain (DBD) and we verified that RNF4 was necessary for AR to regulate the growth of ST cells. Above all, this study suggests that AR regulates ST cell growth via binding to RNF4 and miR-124a, which may help us to further understand the function of AR in spermatogenesis. 相似文献
89.
Ana Carina Heil da Silva Matos Angélica Consalter Bárbara Paula dos Santos Batista Ana Beatriz Monteiro Fonseca Ana Maria Reis Ferreira Juliana da Silva Leite 《Reproduction in domestic animals》2021,56(4):667-672
Granulosa cell tumour, an ovarian neoplasm of stromal origin, is an important tumour related to oestrogenic dominance syndrome and cystic endometrial hyperplasia–pyometra complex. In order to analyse ovarian tumour´s malignant potential, immunohistochemical markers can be used, such as anti-HER2 and anti-Ki-67. The aim of this study was to evaluate the expression of immunohistochemical markers HER-2 and Ki-67 in granulosa cell tumour from bitches´ ovaries. In HER-2 immunomarker analysis using the HercepTest® method, most tumours were classified as 2+ (moderate labelling). Concerning Ki-67 immunomarker, only one case was described as having a high proliferative index. An association was found between immunostained cell percentage by anti-HER-2 antibodies and high pleomorphism, represented by the pattern of follicular/trabecular tumour arrangement. There was no correlation between anti-Ki-67 and anti-HER-2 antibody immunostaining intensities, probably due to only one case with a high Ki-67 index. With an effective protocol for HER-2 and Ki-67 immunohistochemical identification in granulosa cell tumours in bitches, it was possible to characterize this neoplasm proliferation profile. 相似文献
90.
Monika Jamioł Jacek Wawrzykowski Marta Kankofer 《Reproduction in domestic animals》2021,56(7):1040-1049
One of the most important processes determining the proper course of gestation and its physiological termination in cows is the adhesion of epithelial cells allowing for direct contact of maternal and foetal parts of the placenta. Throughout pregnancy, placental cells are under strict hormonal control, which among others regulates the concentration and activity of specific proteins participating in the extracellular matrix remodelling of foetal membranes. The aim of the study was to evaluate the influence of progesterone and prostaglandin F2α on the adhesion of epithelial cells at early-mid pregnancy in cows. Additionally, the impact of selected hormones on anti-adhesive properties of decorin was evaluated. Caruncular epithelial cells were isolated from healthy cows during pregnancy, immediately after slaughter. Primary cell cultures derived from the 2nd and 4th month of gestation were used in the experiments. The viability of cells was assessed by MTT assay. The adhesion of cells to fibronectin was measured spectrophotometrically. The activity of metalloproteinases was confirmed by the metalloproteinase assay. Progesterone (10–5 and 10–7 mol/L) and prostaglandin F2α (10–4, 10–5 and 10–7 mol/L) increased the viability of bovine caruncular epithelial cells in the 2nd month of pregnancy. The treatment with prostaglandin F2α significantly reduced the number of adherent cells from the 2nd month of gestation at the doses of 10–4 and 10–5 mol/L. Both progesterone and prostaglandin F2α were shown to have an effect of decorin resulting in both a decrease in metalloproteinase activity and an increase in adhesion of cells to fibronectin. 相似文献