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71.
VKORC1 genetic polymorphisms affect warfarin dose response, aortic calcification, and the susceptibility of coronary artery disease as shown in our previous study. Little is known regarding the association of VKORC1 polymorphisms with coronary artery calcification (CAC) and the role of CAC in the association with coronary artery disease (CAD). Due to a natural haplotype block in the VKORC1 gene in Chinese, polymorphism rs2359612 was analyzed in a case–control study and a prospective study. The case–control study included 464 CAD patients with non-calcified plaque (NCP), 562 CAD patients with mixed calcified plaque (MCP), 492 subjects with calcified plaque (CP), and 521 controls. The rs2359612C was only associated with increased risk of MCP, the CAD in the presence of CAC; the odds ratio was 1.397 (95 % CI 1.008–1.937, P < 0.05), which was replicated in the second independent population. On the contrary, a negative correlation was observed between rs2359612 and log-transformed Agatston score, and rs2359612 was negatively associated with the number of calcified vessels. Moreover, in a prospective study including 849 CAD patients undergoing revascularization, rs2359612C predicted a higher incidence of cardiovascular events in MCP subgroup; the relative risk was 1.435 (95 % CI 1.008–2.041, P = 0.045), which was not observed in the NCP subgroup. We conclude that the rs2359612C was associated with a higher risk of CAD in the presence of CAC and a higher incidence of cardiovascular events in CAD patients with CAC, but a lower coronary calcification. VKORC1 polymorphisms may be associated with the endophenotype of CAD, calcification-related atherosclerosis.  相似文献   
72.
A mild cerebral ischemic insult, also known as ischemic preconditioning (IPC), confers transient tolerance to a subsequent ischemic challenge in the brain. This study was conducted to investigate whether bone morphogenetic protein-7 (BMP-7) is involved in neuroprotection elicited by IPC in a rat model of ischemia. Ischemic tolerance was induced in rats by IPC (15 min middle cerebral artery occlusion, MCAO) at 48 h before lethal ischemia (2 h MCAO). The present data showed that IPC increased BMP-7 mRNA and protein expression after 24 h reperfusion following ischemia in the brain. In rats of ischemia, IPC-induced reduction of cerebral infarct volume and improvement of neuronal morphology were attenuated when BMP-7 was inhibited either by antagonist noggin or short interfering RNA (siRNA) pre-treatment. Besides, cerebral IPC-induced up-regulation of B-cell lymphoma 2 (Bcl-2) and down-regulation of cleaved caspase-3 at 24 h after ischemia/reperfusion (I/R) injury were reversed via inhibition of BMP-7. These findings indicate that BMP-7 mediates IPC-induced tolerance to cerebral I/R, probably through inhibition of apoptosis.  相似文献   
73.
One criterion for microRNA identification is based on their conservation across species, and prediction of miRNA targets by empirical approaches using computational analysis relies on the presence of conservative mRNA 3′UTR. Because most miRNA target sites identified are highly conserved across different species, it is not clear whether miRNA targeting is species-specific. To predict miRNA targeting, we aligned all available fibronectin 3′UTRs and observed significant conservation of all 20 species. Twelve miRNAs were predicted to target most fibronectin 3′UTRs, but rodent fibronectin showed potential binding sites specific for five different miRNAs. One of them, the miR-378a-5p, contained a complete matching seed-region for all rodent fibronectin, which could not be found in any other species. We designed experiments to test whether the species-specific targeting possessed biological function and found that expression of miR-378a-5p decreased cancer cell proliferation, migration, and invasion, resulting in inhibition of tumor growth. Silencing fibronectin expression produced similar effects as miR-378a-5p, while transfection with a construct targeting miR-378-5p produced opposite results. Tumor formation assay showed that enhanced expression of fibronectin in the stromal tissues as a background environment suppressed tumor growth, while increased fibronectin expression inside the tumor cells promoted tumor growth. This was likely due to the different signaling direction, either inside-out or outside-in signal. Our results demonstrated that species-specific targeting by miRNA could also exert functional effects. Thus, one layer of regulation has been added to the complex network of miRNA signaling.  相似文献   
74.
75.
High-throughput bisulfite sequencing is widely used to measure cytosine methylation at single-base resolution in eukaryotes. It permits systems-level analysis of genomic methylation patterns associated with gene expression and chromatin structure. However, methods for large-scale identification of methylation patterns from bisulfite sequencing are lacking. We developed a comprehensive tool, CpG_MPs, for identification and analysis of the methylation patterns of genomic regions from bisulfite sequencing data. CpG_MPs first normalizes bisulfite sequencing reads into methylation level of CpGs. Then it identifies unmethylated and methylated regions using the methylation status of neighboring CpGs by hotspot extension algorithm without knowledge of pre-defined regions. Furthermore, the conservatively and differentially methylated regions across paired or multiple samples (cells or tissues) are identified by combining a combinatorial algorithm with Shannon entropy. CpG_MPs identified large amounts of genomic regions with different methylation patterns across five human bisulfite sequencing data during cellular differentiation. Different sequence features and significantly cell-specific methylation patterns were observed. These potentially functional regions form candidate regions for functional analysis of DNA methylation during cellular differentiation. CpG_MPs is the first user-friendly tool for identifying methylation patterns of genomic regions from bisulfite sequencing data, permitting further investigation of the biological functions of genome-scale methylation patterns.  相似文献   
76.
The decapeptide CMS001 enhances swimming endurance in mice   总被引:3,自引:0,他引:3  
Wang L  Zhang HL  Lu R  Zhou YJ  Ma R  Lv JQ  Li XL  Chen LJ  Yao Z 《Peptides》2008,29(7):1176-1182
Now peptides achieve distinct advantages over protein in biological application because of its quick and easy absorption, low power, and high activity. Some bioactive peptides had been developed to be used in the management of exercise-related disorders. In this study, we investigated whether the decapeptide CMS001 (Pro-Thr-Thr-Lys-Thr-Tyr-Phe-Pro-His-Phe) isolated from pig spleen had anti-fatigue effects. Male Balb/c mice were administered CMS001 (20 microg/(kgd)(-1) or 5 microg/(kgd)(-1) for 30 d, intraperitoneal injections) and tested in an exhaustive swim time task. In order to examine the mechanisms of CMS001 anti-fatigue effects, we analyzed liver glycogen stores, blood urea nitrogen (BUN) levels, lactic acid levels, ultrastructural integrity, and levels of both a free radical metabolite and an anti-oxidant enzyme. CMS001 treatment prolonged exhaustive swim time, increased liver glycogen levels, reduced BUN levels, and decreased accumulation of lactic acid in the blood, relative to mice injected with only saline. Examination of the ultrastructure of mitochondria and sarcoplasmic reticulum in skeletal and cardiac muscle of CMS001-treated and control mice revealed that CMS001 can reduce the damage to cardiac and skeletal muscle caused by an exhaustive swim challenge, such that the structure of most tissue specimens were normal in the peptide-treated group. Furthermore the free radical analysis after acute exercise indicated that CMS001 treatment decreased malondialdehyde (MDA) and increased superoxide dismutase (SOD) levels. The present findings indicate that the spleen-derived peptide CMS001 has anti-fatigue effects in mice, and further suggest that the mechanism may involve reduction of tissue damaging free radicals in muscle tissues.  相似文献   
77.

Background

The change of serum interleukin-6(IL-6) levels in women with polycystic ovary syndrome (PCOS), as well as the relations between IL-6 levels and body mass index (BMI), insulin resistance(IR) and androgen status of PCOS patients, are not fully understood.

Methods

A literature search was performed in October 2015 using PubMed, Embase and the Cochrane Library databases to identify studies. Random-effects model was used to estimate the standardized mean differences (SMDs) with 95% confidence intervals (CIs).

Results

Twenty articles with 25 case-control studies included 1618 women (922 PCOS patients and 696 controls) were included in this study. IL-6 levels in controls were significantly lower than that of PCOS patients (SMD = 0.78, 95%CI = 0.41–1.16, P<0.001), with significant heterogeneity across studies (I2 = 91% and P<0.001). Meta-regression analysis model indicated IR status was the main source of heterogeneity (P = 0.005). Results from group analysis suggested that high IL-6 levels in PCOS were significantly associated with Homeostasis Model Assessment of Insulin Resistance (HOMA2-IR) ratio and total testosterone ratio (T ratio), and was found in both lean and obese women with PCOS. Cumulative meta-analysis results indicated the total effect size (SMD) had tend to be stable since 2012(0.79 to 0.92).

Conclusions

A high IL-6 level is not an intrinsic characteristic of PCOS, but may be a useful monitoring biomarker for the treatment of PCOS.  相似文献   
78.
Spiramycin is a multicomponent antibiotic, and different components have different antibacterial activities. In Streptomyces spiramyceticus 16-10-2, spiramycin II and spiramycin III (SPMII and SPMIII) are the main components, while spiramycin I (SPMI) needs to be controlled below 12%. Based on this, the influences of Al3+ on total spiramycin titer and components were investigated in this work. Those experiments were mainly performed in 15?L fermentor and Al3+ made a great improvement in spiramycin titer. The optimal adding concentration and adding time of Al3+ were 0.32?g/L at 12?hr. Under this condition, spiramycin titer was increased by 19.51% compared with the control. Moreover, the percentage of SPMII and SPMIII was increased by 7.14%. At the same time, the time of mycelia autolysis was lengthened. In addition, the specific activities of acetyl-CoA synthetase, acetate kinase, acetylphosphotransferase, and acylating enzyme were much higher than those of control. The content of acetic acid and succinic acid was beyond 3 and 4.5 times than that of control, respectively.  相似文献   
79.
Liver damage is the most severe complication of heat stress (HS). Hydrolyzed camel whey protein (CWP) possesses bioactive peptides with obviously antioxidant and anti-inflammatory activities. The current study aims to investigate whether CWP that is hydrolyzed by a simulated gastrointestinal digestion process, named S-CWP, protects BRL-3A hepatocytes from HS-induced damage via antioxidant and anti-inflammatory mechanisms. BRL-3A cells were pretreated with S-CWP before being treated at 43 °C for 1 h, and the levels of the cellular oxidative stress, inflammation, apoptosis, biomarkers for liver function, the activities of several antioxidant enzymes, and the cell viability were analyzed. The expression level of pivotal proteins in correlative signaling pathways was evaluated by western blotting. We confirmed that S-CWP alleviated HS-induced hepatocytes oxidative stress by decreased reactive oxygen species (ROS), nitric oxide (NO), 8-Hydroxy-2′-deoxyguanosine (8-OHdG), lipid peroxidation (LPO), protein carbonylation (PCO), and the activities of NADPH oxidase while enhanced superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), heme oxygenase-1 (HO-1) activities, and GSH content. S-CWP suppressed HS-induced inflammatory response by reducing the phosphorylation of NF-κB p65, the expression of NLRP3, and caspase-1 and finally alleviated caspase-3-mediated apoptosis. S-CWP also alleviated HS-induced hepatocyte injury by reducing alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) levels and restoring Heat Shock Protein 70 (HSP70) expression. Furthermore, S-CWP treatment significantly enhanced the expression of NF-E2-related nuclear factor erythroid-2 (Nrf2) and HO-1. The antioxidant and anti-inflammatory effects of S-CWP were weakened by ML385, a specific Nrf2 inhibitor. Additionally, zinc protoporphyrin (ZnPP), a specific HO-1 inhibitor, significantly reversed S-CWP-induced reduction in the phosphorylation of NF-κB p65. Thus, our results revealed that S-CWP protected against HS-induced hepatocytes damage via activating the Nrf2/HO-1 signaling pathway and inhibiting NF-κB/NLRP3 axis.  相似文献   
80.
The purpose of this study was to investigate immunolocalization of collagenolytic enzymes including cathepsin K, matrix metalloproteinase (MMP) 1 and 2 in the compressed periodontal ligament (PDL) during orthodontic tooth movement using a periostin deficient (Pn-/-) mouse model. Twelve-week-old male mice homozygous for the disrupted periostin gene and their wild type (WT) littermates were used in these experiments. The tooth movement was performed according to Waldo’s method, in which elastic bands of 0.5 mm thickness were inserted between the first and second upper molars of mice under anesthesia. At 1 and 3 days after orthodontic force application, mice were fixed with transcardial perfusion of 4 % paraformaldehyde in 0.1 M phosphate buffer (pH 7.4), and the first molars and peripheral alveolar bones were extracted for histochemical analyses. Compared with WT mice, immunolocalization of cathepsin K, MMP1 and MMP2 was significantly decreased at 1 and 3 days after orthodontic tooth movement in the compressed PDL of Pn-/- mice, although MMP1-reactivity and MMP2-reactivity decreased at different amounts. Very little cathepsin K-immunoreactivity was observed in the assessed regions of Pn-/- mice, both before and after orthodontic force application. Furthermore, Pn-/- mice showed a much wider residual PDL than WT mice. Taken together, we concluded that periostin plays an essential role in the function of collagenolytic enzymes like cathepsin K, MMP1 and MMP2 in the compressed PDL after orthodontic force application.  相似文献   
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