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971.
Coilia mystus is the most important harvested fish species in China; it inhabits quite different water environments during the different life history stages. Populations of C. mystus have dropped sharply due to overharvesting and water pollution. We developed eight microsatellite loci in C. mystus for conservation genetics studies. These new markers were tested in 20 individuals from the Min River in ChangLe. The number of alleles ranged from 3 to 8, the expected heterozygosity from 0.621 to 0.853 and the observed heterozygosity from 0.473-0.800. Only two loci deviated significantly from Hardy-Weinberg expectations due to heterozygote deficiency. These primers may provide a tool for understanding demography and population structure of this economically important and threatened species. 相似文献
972.
Both bacteria and algal symbionts (genus Symbiodinium), the two major microbial partners in the coral holobiont, respond to fluctuations in the environment, according to current reports; however, little evidence yet indicates that both populations have any direct interaction with each other in seasonal fluctuation. In this study, we present field observations of a compositional change in bacteria and Symbiodinium in the coral Isopora palifera in three separate coral colonies following monthly sampling from February to November in 2008. Using massively parallel pyrosequencing, over 200 000 bacterial V6 sequences were classified to build the bacterial community profile; in addition, the relative composition and quantity of Symbiodinium clades C and D were determined by real-time PCR. The results showed that coral-associated bacterial and Symbiodinium communities were highly dynamic and dissimilar among the tagged coral colonies, suggesting that the effect of host specificity was insignificant. The coral-associated bacterial community was more diverse (Shannon index up to 6.71) than previous estimates in other corals and showed rapid seasonal changes. The population ratios between clade C and D groups of Symbiodinium varied in the tagged coral colonies through the different seasons; clade D dominated in most of the samples. Although significant association between bacteria and symbiont was not detected, this study presents a more detailed picture of changes in these two major microbial associates of the coral at the same time, using the latest molecular approaches. 相似文献
973.
974.
Chunlei Miao Dengke Qin Peigang Cao Ping Lu Yutong Xia Mengjiao Li Miao Sun Wei Zhang Fanghong Yang Yingjie Zhang Shengjian Tang Tianyi Liu Fangjun Liu 《Journal of cellular biochemistry》2019,120(5):8754-8763
Bone morphogenetic protein (BMP)2/7 heterodimer shows greater efficacy in enhancing bone regeneration. However, the precise mechanism and the role of mitogen-activated protein kinase (MAPK) signaling network in BMP2/7-driven osteogenesis remain ambiguous. In this study, we evaluated the effects of BMP2/7 heterodimers on osteoblastic differentiation in rat bone marrow mesenchymal stem cells (BMSCs), with the aim to elaborate how MAPKs might be involved in this cellular process by treatment of rat BMSCs with BMP2/-7 with a special signal-pathway inhibitor. We found that BMP2/7 heterodimer induced a much stronger osteogenic response in rat BMSCs compared with either homodimer. Most interestingly, extracellular signal-regulated kinase (ERK) demonstrated a highly sustained phosphorylation and activation in the BMP2/7 heterodimer treatment groups, and inhibition of ERK cascades using U0126 special inhibitor that significantly reduced the activity of ALP and calcium mineralization to a substantial degree in rat BMSCs treated with BMP2/7 heterodimers. Collectively, we demonstrate that BMP2/7 heterodimer shows a potent ability to stimulate osteogenesis in rat BMSCs. The activated ERK signaling pathway involved in this process may contribute partially to an increased osteogenic potency of heterodimeric BMP2/7 growth factors. 相似文献
975.
Multiple studies have reported different methods in treating gestational diabetes mellitus (GDM); however, the relationship between miR-335-5p and GDM still remains unclear. Here, this study explores the effect of miR-335-5p on insulin resistance and pancreatic islet β-cell secretion via activation of the TGFβ signaling pathway by downregulating VASH1 expression in GDM mice. The GDM mouse model was established and mainly treated with miR-335-5p mimic, miR-335-5p inhibitor, si-VASH1, and miR-335-5p inhibitor + si-VASH1. Oral glucose tolerance test (OGTT) was conducted to detect fasting blood glucose (FBG) fasting insulin (FINS). The OGTT was also used to calculate a homeostasis model assessment of insulin resistance (HOMA-IR). A hyperglycemic clamp was performed to measure the glucose infusion rate (GIR), which estimated β-cell function. Expressions of miR-335-5p, VASH1, TGF-β1, and c-Myc in pancreatic islet β-cells were determined by RT-qPCR, western blot analysis, and insulin release by ELISA. The miR-335-5p mimic and si-VASH1 groups showed elevated blood glucose levels, glucose area under the curve (GAUC), and HOMA-IR, but a reduced GIR and positive expression of VASH1. Overexpression of miR-335-5p and inhibition of VASH1 contributed to activated TGFβ1 pathway, higher c-Myc, and lower VASH1 expressions, in addition to downregulated insulin and insulin release levels. These findings provided evidence that miR-335-5p enhanced insulin resistance and suppressed pancreatic islet β-cell secretion by inhibiting VASH1, eventually activating the TGF-β pathway in GDM mice, which provides more clinical insight on the GDM treatment. 相似文献
976.
Hui-Bo Wang Si-Hui Huang Man Xu Jun Yang Jian Yang Ming-Xin Liu Chun-Xia Wan Hai-Han Liao Di Fan Qi-Zhu Tang 《Journal of cellular physiology》2019,234(9):15654-15667
Cardiac remodeling is associated with inflammation and apoptosis. Galangin, as a natural flavonol, has the potent function of regulating inflammation and apoptosis, which are factors related to cardiac remodeling. Beginning 3 days after aortic banding (AB) or Sham surgery, mice were treated with galangin for 4 weeks. Cardiac remodeling was assessed according to echocardiographic parameters, histological analyses, and hypertrophy and fibrosis markers. Our results showed that galangin administration attenuated cardiac hypertrophy, dysfunction, and fibrosis response in AB mice and angiotensin II-treated H9c2 cells. The inhibitory action of galangin in cardiac remodeling was mediated by MEK1/2–extracellular-regulated protein kinases 1/2 (ERK1/2)–GATA4 and phosphoinositide 3-kinase (PI3K)–protein kinase B (AKT)–glycogen synthase kinase 3β (GSK3β) activation. Furthermore, we found that galangin inhibited inflammatory response and apoptosis. Our findings suggest that galangin protects against cardiac remodeling through decreasing inflammatory responses and apoptosis, which are associated with inhibition of the MEK1/2–ERK1/2–GATA4 and PI3K–AKT–GSK3β signals. 相似文献
977.
为优化家蚕杆状病毒表达系统,提高外源基因的表达产量。文中通过同源重组技术,用串联的氯霉素基因(Cm)表达盒和绿色荧光蛋白基因(egfp)表达盒将其替换,从而获得Chitinase和Cystein Protease两个基因缺失的家蚕杆状病毒载体。通过转座,将多角体启动子控制的家蚕二分浓核病毒(Bm BDV)ns1基因表达盒,定点插入到改造后的该分子载体中。将重组载体转染Bm N细胞,获得能表达家蚕二分浓核病毒(Bm BDV)NS1的缺失型重组病毒;另外,将多角体启动子控制的ns1基因转座到野生型Bm-bacmid中,获得能表达Bm BDV NS1的野生型重组病毒。将这两种病毒分别皮下注射家蚕,对感染后的家蚕血液中NS1表达水平进行比较,发现缺失Chitinase和Cystein Protease重组病毒感染的家蚕血液中,NS1的表达量是对照组的3倍,从而建立了一种高效表达可溶性NS1蛋白的方法,为靶蛋白的结构与功能研究奠定基础。 相似文献
978.
Use of random forest in FTIR analysis of LDL cholesterol and tri‐glycerides for hyperlipidemia 下载免费PDF全文
A quantitative determination method for the diagnosis of hyperlipidemia was developed using Fourier transform infrared (FTIR) spectroscopy. Random forest (RF) was demonstrated as a potential multivariate algorithm for the FTIR analysis of low‐density lipoprotein cholesterol (LDL‐C) and tri‐glycerides (TG) in human serum samples. The informative wavebands for LDL‐C and TG were selected based on the Gini importance. The selected wavebands were mainly within the fingerprint region. The RF modeling results were better than those derived using PLS in validation process, because the chance for over‐fitting was possibly eliminated in RF algorithm. ARF also demonstrated favorable results in the test process. The prospective model exhibited a higher than 90% true prediction in negative/positive properties for male and female samples. These clinical statistical results indicated the optimization of RF algorithm performed accurately in the FTIR determination of LDL‐C and TG. RF is evaluated as a promising tool for diagnosing and controlling hyperlipidemia in populations. The parameter optimization methodology is useful in the improving model accuracy using FTIR spectroscopic technology. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1693–1702, 2015 相似文献
979.
980.