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101.
Fecundity improvement is one of the most important objectives for goat breeders as it greatly increases production efficiency. To investigate the genes associated with litter sizes in the Anhui White goat (AWG), gene expression differences in the ovaries of uniparous and multiparous AWG were assessed using the RNA-Seq (Quantification) method. This analysis generated 6,027,714 and 5,884,062 clean reads in uniparous and multiparous libraries, respectively. A total of 2201 differentially expressed genes (DEGs) were thereby identified (FDR ≤ 0.001, |log2Ratio| ≥ 1). There were 1583 up-regulated and 618 down-regulated genes in the multiparous samples compared with the uniparous samples. A large number of these DEGs were related to the terms cellular process, cell & cell part and binding. Twelve genes which may be associated with the high prolificacy of AWG were identified using a bioinformatic screen. In addition, pathway analysis revealed that these DEGs were significantly enriched in 11 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, including ECM–receptor interactions, focal adhesion, and regulation of the actin cytoskeleton among others. This suggested a role for these pathways in the prolificacy of AWG. These results provide a list of new candidate genes for goat prolificacy.  相似文献   
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Increased incidence of arrhythmias in women after menopause has been widely documented, which is considered to be related to estrogen (E2) deficiency induced cardiac electrophysiological abnormalities. However, its molecular mechanism remains incompletely clear. In the present study, we found cardiac conduction blockage in post-menopausal rats. Thereafter, the results showed that cardiac gap junctions were impaired and Connexin43 (Cx43) expression was reduced in the myocardium of post-menopausal rats. The phenomenon was also observed in ovariectomized (OVX) rats, which was attenuated by E2 supplement. Further study displayed that microRNA-23a (miR-23a) level was significantly increased in both post-menopausal and OVX rats, which was reversed by daily E2 treatment after OVX. Importantly, forced overexpression of miR-23a led to gap junction impairment and Cx43 downregulation in cultured cardiomyocytes, which was rescued by suppressing miR-23a by transfection of miR-23a specific inhibitory oligonucleotide (AMO-23a). GJA1 was identified as the target gene of miR-23a by luciferase assay and miRNA-masking antisense ODN (miR-Mask) assay. We also found that E2 supplement could reverse cardiac conduction blockage, Cx43 downregulation, gap junction remodeling and miR-23a upregulation in post-menopausal rats. These findings provide the evidence that miR-23a mediated repression of Cx43 participates in estrogen deficiency induced damages of cardiac gap junction, and highlights a new insight into molecular mechanism of post-menopause related arrhythmia at the microRNA level.  相似文献   
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Amyloid-like fibrils have been associated with the pathogenesis of human prion diseases. Prion peptide of aa 106-126 (PrP106-126) exhibits many PrP(Sc)-like biochemical features, forming amyloid-like fibrils in vitro. Here, we found that the recombinant yeast-derived molecular chaperon Hsp104 inhibited significantly the fibril assembly of the synthetic PrP106-126 peptide by dynamic ThT assays in vitro. EM assays revealed almost no fibril-like structure after incubation of the synthetic PrP106-126 peptides with Hsp104 for 12h. Circular dichroism assays identified that treatment of Hsp104 shifted the secondary structure of PrP106-126 fibrils from β-sheet to a random coil. MTT tests confirmed that interaction of PrP106-126 with Hsp104 maintained the toxicity of PrP106-126 on human neuroblastoma cell line SK-N-SH. Additionally, Hsp104 was able to disassemble the mature PrP106-126 fibrils in vitro, leading to recovering the cytotoxicity of PrP106-126 on SK-N-SH cells. Our study provides the molecular evidences that the yeast-derived Hsp104 can interfere in the fibril assembly and disassembly of human PrP106-126 segment.  相似文献   
107.

Objective

To review the effects of core stability exercise or general exercise for patients with chronic low back pain (LBP).

Summary of Background Data

Exercise therapy appears to be effective at decreasing pain and improving function for patients with chronic LBP in practice guidelines. Core stability exercise is becoming increasingly popular for LBP. However, it is currently unknown whether core stability exercise produces more beneficial effects than general exercise in patients with chronic LBP.

Methods

Published articles from 1970 to October 2011 were identified using electronic searches. For this meta-analysis, two reviewers independently selected relevant randomized controlled trials (RCTs) investigating core stability exercise versus general exercise for the treatment of patients with chronic LBP. Data were extracted independently by the same two individuals who selected the studies.

Results

From the 28 potentially relevant trials, a total of 5 trials involving 414 participants were included in the current analysis. The pooling revealed that core stability exercise was better than general exercise for reducing pain [mean difference (−1.29); 95% confidence interval (−2.47, −0.11); P = 0.003] and disability [mean difference (−7.14); 95% confidence interval (−11.64, −2.65); P = 0.002] at the time of the short-term follow-up. However, no significant differences were observed between core stability exercise and general exercise in reducing pain at 6 months [mean difference (−0.50); 95% confidence interval (−1.36, 0.36); P = 0.26] and 12 months [mean difference (−0.32); 95% confidence interval (−0.87, 0.23); P = 0.25].

Conclusions

Compared to general exercise, core stability exercise is more effective in decreasing pain and may improve physical function in patients with chronic LBP in the short term. However, no significant long-term differences in pain severity were observed between patients who engaged in core stability exercise versus those who engaged in general exercise.

Systematic Review Registration

http://www.crd.york.ac.uk/PROSPERO PROSPERO registration number: CRD42011001717.  相似文献   
108.
Apoptin, a viral death protein derived from chicken anemia virus, displays a number of tumor-specific behaviors. In particular, apoptin is phosphorylated, translocates to the nucleus, and induces apoptosis specifically in tumor or transformed cells, whereas it is nonphosphorylated and remains primarily inactive in the cytoplasm of nontransformed normal cells. Here, we show that in normal cells apoptin can also be activated by the transient transforming signals conferred by ectopically expressed simian virus 40 (SV40) large T antigen (LT), which rapidly induces apoptin's phosphorylation, nuclear accumulation, and the ability to induce apoptosis. Further analyses with mutants of LT showed that the minimum domain capable of inducing all three of apoptin's tumor-specific properties resided in the N-terminal J domain, a sequence which is largely shared by SV40 small t antigen (st). Interestingly, the J domain in st, which lacks its own nuclear localization signal (NLS), required nuclear localization to activate apoptin. These results reveal the existence of a cellular pathway shared by conditions of transient transformation and the stable cancerous or precancerous state, and they support a model whereby a transient transforming signal confers on apoptin both the upstream activity of phosphorylation and the downstream activity of nuclear accumulation and apoptosis induction. Such a pathway may reflect a general lesion contributing to human cancers.  相似文献   
109.
Recently, the small regions of some proteins suchas human immunodeficiency virus type 1 (HIV-1) Tat-(48-60) and Drosophila Antennapedia-(43-58) have beenreported to have the ability to translocate through the cellmembranes and carry the exogenous molecules into cyto-plasm and nucleus, and are called membrane-permeablepeptides (MPPs) [1–14]. Delivery of bioactive peptidesacross the blood-brain barrier is generally restricted to small(6 amino acids or less) or highly lipophilic peptides. But…  相似文献   
110.
Li  Ying-Hui  Qin  Chao  Wang  Li  Jiao  Chengzhi  Hong  Huilong  Tian  Yu  Li  Yanfei  Xing  Guangnan  Wang  Jun  Gu  Yongzhe  Gao  Xingpeng  Li  Delin  Li  Hongyu  Liu  Zhangxiong  Jing  Xin  Feng  Beibei  Zhao  Tao  Guan  Rongxia  Guo  Yong  Liu  Jun  Yan  Zhe  Zhang  Lijuan  Ge  Tianli  Li  Xiangkong  Wang  Xiaobo  Qiu  Hongmei  Zhang  Wanhai  Luan  Xiaoyan  Han  Yingpeng  Han  Dezhi  Chang  Ruzhen  Guo  Yalong  Reif  Jochen C.  Jackson  Scott A.  Liu  Bin  Tian  Shilin  Qiu  Li-juan 《中国科学:生命科学英文版》2023,66(2):350-365

Soybean is a leguminous crop that provides oil and protein. Exploring the genomic signatures of soybean evolution is crucial for breeding varieties with improved adaptability to environmental extremes. We analyzed the genome sequences of 2,214 soybeans and proposed a soybean evolutionary route, i.e., the expansion of annual wild soybean (Glycine soja Sieb. & Zucc.) from southern China and its domestication in central China, followed by the expansion and local breeding selection of its landraces (G. max (L.) Merr.). We observed that the genetic introgression in soybean landraces was mostly derived from sympatric rather than allopatric wild populations during the geographic expansion. Soybean expansion and breeding were accompanied by the positive selection of flowering time genes, including GmSPA3c. Our study sheds light on the evolutionary history of soybean and provides valuable genetic resources for its future breeding.

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