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131.
Mi YY  Zhu LJ  Wu S  Feng NH 《Genes & nutrition》2011,6(4):397-402
Encoding ribonuclease L (RNASEL) is a ubiquitously expressed latent endoribonuclease involved in the mediation of antiviral and pro-apoptotic activities of the interferon-inducible 2-5A system. Although the relationship between RNASEL gene polymorphisms and prostate cancer (PCa) risk has been widely reported, results were somewhat controversial and underpowered. Now, we performed an update analysis of 14 publications evaluating the association between RNASEL R462Q and D541E polymorphisms and PCa risk. We conducted a literature search of PubMed database to identify all eligible articles that examined the association of RNASEL R462Q and D541E polymorphisms with PCa. Odds ratios (OR) with 95% confidence intervals (CI) were estimated to assess these association. R462Q showed a significantly elevated effect on Africans (QQ vs. RR: OR = 2.50, 95% CI = 1.28–4.87, Pheterogeneity = 0.231). In addition, PCa men who contain 462Q genotype had a higher Gleason score ≥ 7 (OR = 1.16, 95% CI = 1.05–1.28, Pheterogeneity = 0.906). On the other hand, D541E was associated with increased total PCa. In the stratified analysis by race, there was also significantly increased PCa in Africans and Caucasians, as well as in sporadic PCa studies (OR = 1.09, 95% CI = 1.04–1.15, Pheterogeneity = 0.078). Our update analysis showed evidence that RNASEL R462Q and D541E polymorphisms were associated with PCa risk. Still more well-designed studies should be performed to clarify the role of these two polymorphisms in the development of PCa.  相似文献   
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133.
Mesenchymal stem cells (MSCs) reside in almost all of the body tissues, where they undergo self-renewal and multi-lineage differentiation. MSCs derived from different tissues share many similarities but also show some differences in term of biological properties. We aim to search for significant differences among various sources of MSCs and to explore their implications in physiopathology and clinical translation. We compared the phenotype and biological properties among different MSCs isolated from human term placental chorionic villi (CV), umbilical cord (UC), adult bone marrow (BM) and adipose (AD). We found that CD106 (VCAM-1) was expressed highest on the CV-MSCs, moderately on BM-MSCs, lightly on UC-MSCs and absent on AD-MSCs. CV-MSCs also showed unique immune-associated gene expression and immunomodulation. We thus separated CD106+cells and CD106cells from CV-MSCs and compared their biological activities. Both two subpopulations were capable of osteogenic and adipogenic differentiation while CD106+CV-MSCs were more effective to modulate T helper subsets but possessed decreased colony formation capacity. In addition, CD106+CV-MSCs expressed more cytokines than CD106CV-MSCs. These data demonstrate that CD106 identifies a subpopulation of CV-MSCs with unique immunoregulatory activity and reveal a previously unrecognized mechanism underlying immunomodulation of MSCs.  相似文献   
134.
560 blood samples collected from mentally retarded children in Taipei were karyotypically analyzed for the incidence of fragile X and other chromosome abnormalities. The fragile site at Xq27.3 was observed in 18 patients (3.21%), 11 males and 7 females, out of the 560 blood cultures using M medium. Down syndrome (6.25%), 24 males and 11 females, was the other major category of abnormality. Other abnormalities, including inversion, translocation, deletion, duplication, ring as well as an extra marker chromosome were observed. The overall incidence of chromosomal abnormalities in these children was 14.82%.  相似文献   
135.
The Ca2+ paradox represents a good model to study Ca2+ overload injury in ischemic heart diseases. We and others have demonstrated that contracture and calpain are involved in the Ca2+ paradox-induced injury. This study aimed to elucidate their roles in this model. The Ca2+ paradox was elicited by perfusing isolated rat hearts with Ca2+-free KH media for 3 min or 5 min followed by 30 min of Ca2+ repletion. The LVDP was measured to reflect contractile function, and the LVEDP was measured to indicate contracture. TTC staining and the quantification of LDH release were used to define cell death. Calpain activity and troponin I release were measured after Ca2+ repletion. Ca2+ repletion of the once 3-min Ca2+ depleted hearts resulted in almost no viable tissues and the disappearance of contractile function. Compared to the effects of the calpain inhibitor MDL28170, KB-R7943, an inhibitor of the Na+/Ca2+ exchanger, reduced the LVEDP level to a greater extent, which was well correlated with improved contractile function recovery and tissue survival. The depletion of Ca2+ for 5 min had the same effects on injury as the 3-min Ca2+ depletion, except that the LVEDP in the 5-min Ca2+ depletion group was lower than the level in the 3-min Ca2+ depletion group. KB-R7943 failed to reduce the level of LVEDP, with no improvement in the LVDP recovery in the hearts subjected to the 5-min Ca2+ depletion treatment; however, KB-R7943 preserved its protective effects in surviving tissue. Both KB-R7943 and MDL28170 attenuated the Ca2+ repletion-induced increase in calpain activity in 3 min or 5 min Ca2+ depleted hearts. However, only KB-R7943 reduced the release of troponin I from the Ca2+ paradoxic heart. These results provide evidence suggesting that contracture is the main cause for contractile dysfunction, while activation of calpain mediates cell death in the Ca2+ paradox.  相似文献   
136.
Phosphotyrosyl phosphatase activator (PTPA) is decreased in the brains of Alzheimer's disease (AD) and the AD transgenic mouse models. Here, we investigated whether down‐regulation of PTPA affects cell viability and the underlying mechanisms. We found that PTPA was located in the integral membrane of mitochondria, and knockdown of PTPA induced cell apoptosis in HEK293 and N2a cell lines. PTPA knockdown decreased mitochondrial membrane potential and induced Bax translocation into the mitochondria with a simultaneous release of Cyt C, activation of caspase‐3, cleavage of poly (DNA ribose) polymerase (PARP), and decrease in Bcl‐xl and Bcl‐2 protein levels. Over‐expression of Protein phosphatase 2A (PP2A) catalytic subunit (PP2AC) did not rescue the apoptosis induced by PTPA knockdown, and PTPA knockdown did not affect the level of and their phosphorylation of mitogen‐activated protein kinases (MAPKs), indicating that PP2A and MAPKs were not involved in the apoptosis induced by PTPA knockdown. In the cells with over‐expression of tau, PTPA knockdown induced PP2A inhibition and tau hyperphosphorylation but did not cause significant cell death. These data suggest that PTPA deficit causes apoptotic cell death through mitochondrial pathway and simultaneous tau hyperphosphorylation attenuates the PTPA‐induced cell death.

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137.

Background

The one-step blending approach has been suggested for genomic prediction in dairy cattle. The core of this approach is to incorporate pedigree and phenotypic information of non-genotyped animals. The objective of this study was to investigate the improvement of the accuracy of genomic prediction using the one-step blending method in Chinese Holstein cattle.

Findings

Three methods, GBLUP (genomic best linear unbiased prediction), original one-step blending with a genomic relationship matrix, and adjusted one-step blending with an adjusted genomic relationship matrix, were compared with respect to the accuracy of genomic prediction for five milk production traits in Chinese Holstein. For the two one-step blending methods, de-regressed proofs of 17 509 non-genotyped cows, including 424 dams and 17 085 half-sisters of the validation cows, were incorporated in the prediction model. The results showed that, averaged over the five milk production traits, the one-step blending increased the accuracy of genomic prediction by about 0.12 compared to GBLUP. No further improvement in accuracies was obtained from the adjusted one-step blending over the original one-step blending in our situation. Improvements in accuracies obtained with both one-step blending methods were almost completely contributed by the non-genotyped dams.

Conclusions

Compared with GBLUP, the one-step blending approach can significantly improve the accuracy of genomic prediction for milk production traits in Chinese Holstein cattle. Thus, the one-step blending is a promising approach for practical genomic selection in Chinese Holstein cattle, where the reference population mainly consists of cows.  相似文献   
138.
139.
The epimerization and dehydration reactions of the 17 beta-hydroxy group of anabolic 17 beta-hydroxy-17 alpha-methyl steroids have been investigated using the pyridinium salts of 17 beta-sulfate derivatives of methandienone 1, methyltestosterone 4, oxandrolone 7, mestanolone 10 and stanozolol 11 as model compounds. Rearrangement of the sulfate conjugates in buffered urine (pH 5.2) afforded the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes in a ratio of 0.8:1. These data indicated that both epimerization and dehydration of the 17 beta-sulfate derivatives were not dependent upon the respective chemical features of the steroids studied, but were instead inherent to the chemistry of the tertiary 17 beta-hydroxy group of these steroids. Interestingly, in vivo studies carried out with human male volunteers showed that only methandienone 1, methyltestosterone 4 and oxandrolone 7 yielded the corresponding 17-epimers 2, 5 and 8 and the 18-nor-17,17-dimethyl-13(14)-enes 3, 6 and 9 in ratios of 0.5:1, 2:1 and 2.7:1, respectively. No trace of the corresponding 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of mestanolone 10 and stanozolol 11 was detected in urine samples collected after administration of these steroids. These data suggested that the in vivo formation of the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes derivatives of 17 beta-hydroxy-17 alpha-methyl steroids is also dependent upon phase I and phase II metabolic reactions other than sulfation of the tertiary 17 beta-hydroxyl group, which are probably modulated by the respective chemical features of the steroidal substrates. The data reported in this study demonstrate that the 17-epimers and 18-nor-17,17-dimethyl-13(14)-enes are not artifacts resulting from the acidic or microbial degradation of the parent steroids in the gut as previously suggested by other authors, but arise from the rearrangement of their 17 beta-sulfate derivatives. Unchanged oxandrolone 7 was solely detected in the unconjugated steroid fraction whereas unchanged steroids 1, 4 and 11 were recovered from the glucuronide fraction. These data are indirect evidences suggesting that the glucuronide conjugates of compounds 1 and 4 are probably enol glucuronides and that of compound 11 is excreted in urine as a N-glucuronide involving its pyrazole moiety. The urinary excretion profiles of the epimeric and 18-nor-17,17-dimethyl-13(14)-ene steroids are presented and discussed on the basis of their structural features.  相似文献   
140.
Wang  Ning  Gao  Qing  Shi  Jie  Yulan  Chen  Ji  Weimeng  Sheng  Xiumei  Zhang  Rui 《Molecular biology reports》2022,49(9):8727-8740
Molecular Biology Reports - During the pathogenesis and progression of diabetes, lipotoxicity is a major threat to the function and survival of pancreatic β-cells. To battle against the...  相似文献   
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