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991.
Concurrent infection with hepatitis C virus (HCV) and hepatitis B virus (HBV) was not uncommon in China. To date, information on predictors of response to treatment of dually-infected HCV/HBV is limited. The aim of this study was to evaluated whether determination of the interleukin 28B (IL-28B) polymorphism statuses sufficient to predict treatment response of interferon (IFN)-based therapy in patients chronically infected with both hepatitis B and C viruses. We investigated the role of IL28B variations (rs8099917 and rs12979860) in response to IFN-based treatment and evaluated its association with the risk of the null virological response (NVR) in HCV /HBV dually-infected patients. We found that the overall distributions of the genotypes among the sustained virological response (SVR), NVR groups were significantly different (P<0.001): patients with the rs8099917 TG genotype had an increased risk of NVR (odds ratio [OR] =2.37 95% confidence interval [CI] =1.16–4.83, P =0.017), and those with the GG genotype had a further increased risk of NVR (OR=4.23, 95% CI =1.17-15.3, P=0.027). The rs12979860 allele was also highly associated with treatment failure (CT/TT vs. CC; OR =2.04, 95%CI =1.05-3.97, P =0.037). Moreover, we found that IL28B rs8099917 G variants (TG+GG) interact with HCV genotype 1(G1) to result in higher risk of NVR (P=0.009), and that they are also associated with HBV DNA reactivation (TG+GG vs. TT, P=0.005). Furthermore, multivariate regression analysis show that the rs8099917 G allele was the most important factor significantly associated with a NVR in HCV G1 patients. This study suggest that IL28B genotyping may be a valid pretreatment predictor of which patients are likely to respond to treatment in this group of difficult-to-treat HCV/HBV dually-infected patients.  相似文献   
992.

Background

Epidemiological evidence suggests that vitamin D deficiency is linked to various chronic diseases. However direct measurement of serum 25-hydroxyvitamin D (25(OH)D) concentration, the accepted biomarker of vitamin D status, may not be feasible in large epidemiological studies. An alternative approach is to estimate vitamin D status using a predictive model based on parameters derived from questionnaire data. In previous studies, models developed using Multiple Linear Regression (MLR) have explained a limited proportion of the variance and predicted values have correlated only modestly with measured values. Here, a new modelling approach, nonlinear radial basis function support vector regression (RBF SVR), was used in prediction of serum 25(OH)D concentration. Predicted scores were compared with those from a MLR model.

Methods

Determinants of serum 25(OH)D in Caucasian adults (n = 494) that had been previously identified were modelled using MLR and RBF SVR to develop a 25(OH)D prediction score and then validated in an independent dataset. The correlation between actual and predicted serum 25(OH)D concentrations was analysed with a Pearson correlation coefficient.

Results

Better correlation was observed between predicted scores and measured 25(OH)D concentrations using the RBF SVR model in comparison with MLR (Pearson correlation coefficient: 0.74 for RBF SVR; 0.51 for MLR). The RBF SVR model was more accurately able to identify individuals with lower 25(OH)D levels (<75 nmol/L).

Conclusion

Using identical determinants, the RBF SVR model provided improved prediction of serum 25(OH)D concentrations and vitamin D deficiency compared with a MLR model, in this dataset.  相似文献   
993.

Purpose

Non-suicidal self-injury (NSSI) in adolescent has drawn increasing attention because it is associated with subsequent depression, drug abuse, anxiety disorders, and suicide. In the present study, we aimed to estimate the prevalence of non-suicidal self-injury (NSSI) in a school-based sample of Chinese adolescents and to explore the association between aggression and NSSI.

Methods

This study was part of a nationwide study on aggression among adolescents in urban areas of China. A sample of 2907 school students including 1436 boys and 1471 girls were randomly selected in Guangdong Province, with their age ranging from 10 to 18 years old. NSSI, aggression, emotional management and other factors were measured by self-administrated questionnaire. Multinomial logistic regression was used to estimate the association between aggression and NSSI, after adjustment for participants’ emotional management, and other potential confounding variables.

Results

The one year self-reported prevalence of NSSI was 33.6%. Of them, 21.7% engaged in ‘minor NSSI’, 11.9% in ‘moderate/severe NSSI’. 96.9% of self-injuries engaged in one to five different types of NSSI in the past year. Hostility, verbal and indirect aggression was significantly associated with self-reported NSSI after adjusting for other potential factors both in ‘minor NSSI’ and ‘moderate/severe NSSI’. Hostility, verbal and indirect aggression was significantly associated with greater risk of ‘minor NSSI’ and ‘moderate/severe NSSI’ in those who had poor emotional management ability.

Conclusion

These findings highlight a high prevalence of NSSI and indicate the importance of hostility, verbal and indirect aggression as potentially risk factor for NSSI among Chinese adolescents.  相似文献   
994.

Background

The treatment of patients with MDR- and XDR-TB is usually more complex, toxic and costly and less effective than treatment of other forms of TB. However, there is little information available on risk factors for poor outcomes in patients with MDR- and XDR-TB in China.

Methodology/Principal Findings

We retrospectively analyzed the clinical records of HIV-negative TB Patients with culture-proven MDR- or XDR-TB who were registered from July 2006 to June 2011 at five large-scale Tuberculosis Specialized Hospitals in China. Among 1662 HIV-seronegative TB cases which were culture-positive for M. tuberculosis complex and had positive sputum-smear microscopy results, 965 cases (58.1%) were DR-TB, and 586 cases (35.3%) were classified as having MDR-TB, accounting for 60.7% of DR-TB. 169 cases (10.2%) were XDR-TB, accounting for 17.5% of DR-TB, 28.8% of MDR-TB. The MDR-TB patients were divided into XDR-TB group (n=169) and other MDR-TB group (non-XDR MDR-TB) (n=417). In total, 240 patients (40.95%) had treatment success, and 346 (59.05%) had poor treatment outcomes. The treatment success rate in other MDR-TB group was 52.2%, significantly higher than that in the XDR-TB group (13%, P<0.001). In multivariate logistic regression analysis, poor outcomes were associated with duration of previous anti-TB treatment of more than one year (OR, 0.077; 95% CI, 0.011-0.499, P<0.001), a BMI less than 18.5 kg/m2 (OR, 2.185; 95% CI, 1.372-3.478, P<0.001), XDR (OR, 13.368; 95% CI, 6.745-26.497, P<0.001), retreatment (OR, 0.171; 95% CI, 0.093-0.314, P<0.001), diabetes (OR, 0.305; 95% CI, 0.140-0.663, P=0.003), tumor (OR, 0.095; 95% CI, 0.011-0.795, P=0.03), decreased albumin (OR, 0.181; 95% CI, 0.118-0.295, P<0.001), cavitation (OR, 0.175; 95% CI, 0.108-0.286, P<0.001).

Conclusions/Significance

The patients with MDR-TB and XDR-TB have poor treatment outcomes in China.The presence of extensive drug resistance, low BMI, hypoalbuminemia, comorbidity, cavitary disease and previous anti-TB treatment are independent prognostic factors for poor outcome in patients with MDR-TB.  相似文献   
995.

Background

Although the Newcastle disease virus (NDV) inactivated vaccines and attenuated live vaccines have been used to prevent and control Newcastle disease (ND) for years, there are some disadvantages. Recently, newly developed DNA vaccines have the potential to overcome these disadvantages. The low delivery efficiency, however, hindered the application of DNA vaccines for ND in practice.

Methodology/Principal Findings

The eukaryotic expression plasmid pVAX1-F (o) DNA that expressed the F gene of NDV encapsulated in PLGA nanoparticles (pFNDV-PLGA-NPs) were prepared by a double emulsion-solvent evaporation method and optimal preparation conditions of the pFNDV-PLGA-NPs were determined. Under the optimal conditions, the pFNDV-PLGA-NPs were produced in good morphology and had high stability with a mean diameter of 433.5±7.5 nm, with encapsulation efficiency of 91.8±0.3% and a Zeta potential of +2.7 mV. Release assay in vitro showed that the fusion gene plasmid DNA could be sustainably released from the pFNDV-PLGA-NPs up to 93.14% of the total amount. Cell transfection test indicated that the vaccine expressed and maintained its bioactivity. Immunization results showed that better immune responses of SPF chickens immunized with the pFNDV-PLGA-NPs were induced compared to the chickens immunized with the DNA vaccine alone. In addition, the safety of mucosal immunity delivery system of the pFNDV-PLGA-NPs was also tested in an in vitro cytotoxicity assay.

Conclusions/Significance

The pFNDV-PLGA-NPs could induce stronger cellular, humoral, and mucosal immune responses and reached the sustained release effect. These results laid a foundation for further development of vaccines and drugs in PLGA nanoparticles.  相似文献   
996.
Studies of linkage and association in various ethnic populations have revealed many predisposing genes of multiple neurotransmitter systems for alcohol use disorders (AUD). However, evidence often is contradictory regarding the contribution of most candidate genes to the susceptibility of AUD. We, therefore, performed a case-control study to investigate the possible associations of genes selected from multiple neurotransmitter systems with AUD in a homogeneous Tibetan community population in China. AUD cases (N = 281) with an alcohol use disorder identification test (AUDIT) score ≥10, as well as healthy controls (N = 277) with an AUDIT score ≤5, were recruited. All participants were genotyped for 366 single nucleotide polymorphisms (SNPs) of 34 genes selected from those involved in neurotransmitter systems. Association analyses were performed using PLINK version 1.07 software. Allelic analyses before adjustment for multiple tests showed that 15 polymorphisms within seven genes were associated with AUD (p<0.05). After adjustment for the number of SNPs genotyped within each gene, only the association of a single marker (rs10044881) in HTR4 remained statistically significant. Haplotype analysis for two SNPs in HTR4 (rs17777298 and rs10044881) showed that the haplotype AG was significantly associated with the protective effect for AUD. In conclusion, the present study discovered that the HTR4 gene may play a marked role in the pathogenesis of AUD. In addition, this Tibetan population sample marginally replicated previous evidence regarding the associations of six genes in AUD.  相似文献   
997.

Objectives

Hypervitaminosis A and alcoholism can result in a low mineral density and compromised regenerative capacity of bone, thus delaying implant osteointegration. The inhibitory effect of all-trans retinoic acid on osteoblastogenesis is considered to be one of the mechanisms. We hypothesized that heterodimeric bone morphogenetic protein-2/7 could antagonize all-trans retinoic acid and enhance osteoblastogenesis, with an aim to accelerate and enhance bone regeneration and implant osteointegration.

Materials and Methods

We applied 5 ng/ml or 50 ng/ml bone morphogenetic protein-2/7 to restore the osteoblastogenesis of pre-osteoblasts (MC3T3-E1 cell line) that was inhibited by 1 µM all-trans retinoic acid. We evaluated the efficacy by assessing cell numbers (proliferation), alkaline phosphatase activity (a marker for early differentiation), osteocalcin (a marker for late differentiation), calcium deposition (a marker for final mineralization) and the expression of osteoblastogenic genes (such as Runx2, Collagen Ia, alkaline phosphatase and osteocalcin) at different time points.

Results

All-trans retinoic acid significantly inhibited the expression of all the tested osteoblastogenic genes and proteins except alkaline phosphatase activity. In the presence of ATRA, 50 ng/ml bone morphogenetic protein-2/7 not only completely restored but also significantly enhanced all the osteoblastogenic genes and proteins. On the 28th day, mineralization was completely inhibited by all-trans retinoic acid. In contrast, 50 ng/ml BMP-2/7 could antagonize ATRA and significantly enhance the mineralization about 2.5 folds in comparison with the control treatment (no ATRA, no BMP2/7).

Conclusions

Heterodimeric bone morphogenetic protein-2/7 bears a promising application potential to significantly promote bone regeneration and implant osteointegration for the patients with hypervitaminosis A and alcoholism.  相似文献   
998.

Background

In women with ischemia and no obstructive coronary artery disease, the Women''s Ischemic Syndrome Evaluation (WISE) observed that microvascular coronary dysfunction (MCD) is the best independent predictor of adverse cardiovascular events. Since coronary microvascular tone is regulated in part by endothelium, we hypothesized that circulating endothelial cells (CEC), which reflect endothelial injury, and the number and function of bone-marrow derived angiogenic cells (BMDAC), which could help repair damaged endothelium, may serve as biomarkers for decreased coronary flow reserve (CFR) and MCD.

Methods

We studied 32 women from the WISE cohort. CFR measurements in response to intracoronary adenosine were taken as an index of MCD. We enumerated BMDAC colonies and CEC in peripheral blood samples. BMDAC function was assessed by assay of migration of CD34+ cells toward SDF-1 and measurement of bioavailable nitric oxide (NO). These findings were compared with a healthy reference group and also entered into a multivariable model with CFR as the dependent variable.

Results

Compared with a healthy reference group, women with MCD had lower numbers of BMDAC colonies [16 (0, 81) vs. 24 (14, 88); P = 0.01] and NO [936 (156, 1875) vs. 1168 (668, 1823); P = 0.02]. Multivariable regression analysis showed strong correlation of CFR to the combination of BMDAC colony count and CD34+ cell function (migration and NO) (R2 = 0.45; P<0.05).

Conclusions

The BMDAC function and numbers of BMDAC colonies are decreased in symptomatic women with MCD and are independently associated with CFR. These circulating cells may provide mechanistic insights into MCD in women with ischemia.  相似文献   
999.

Objective

The worldwide prevalence of obesity mandates a widely accessible tool to categorize adiposity that can best predict associated health risks. The body adiposity index (BAI) was designed as a single equation to predict body adiposity in pooled analysis of both genders. We compared body adiposity index (BAI), body mass index (BMI), and other anthropometric measures, including percent body fat (PBF), in their correlations with cardiometabolic risk factors. We also compared BAI with BMI to determine which index is a better predictor of PBF.

Methods

The cohort consisted of 698 Mexican Americans. We calculated correlations of BAI, BMI, and other anthropometric measurements (PBF measured by dual energy X-ray absorptiometry, waist and hip circumference, height, weight) with glucose homeostasis indices (including insulin sensitivity and insulin clearance from euglycemic clamp), lipid parameters, cardiovascular traits (including carotid intima-media thickness), and biomarkers (C-reactive protein, plasminogen activator inhibitor-1 and adiponectin). Correlations between each anthropometric measure and cardiometabolic trait were compared in both sex-pooled and sex-stratified groups.

Results

BMI was associated with all but two measured traits (carotid intima-media thickness and fasting glucose in men), while BAI lacked association with several variables. BAI did not outperform BMI in its associations with any cardiometabolic trait. BAI was correlated more strongly than BMI with PBF in sex-pooled analyses (r = 0.78 versus r = 0.51), but not in sex-stratified analyses (men, r = 0.63 versus r = 0.79; women, r = 0.69 versus r = 0.77). Additionally, PBF showed fewer correlations with cardiometabolic risk factors than BMI. Weight was more strongly correlated than hip with many of the cardiometabolic risk factors examined.

Conclusions

BAI is inferior to the widely used BMI as a correlate of the cardiometabolic risk factors studied. Additionally, BMI’s relationship with total adiposity may not be the sole determinate of its association with cardiometabolic risk.  相似文献   
1000.

Objective

Inflammatory bowel disease (IBD) is commonly treated with thiopurines such as azathioprine and mercaptopurine for the maintenance of remission. Studies examining chemopreventive of these medications on colorectal neoplasm in IBD patients have yielded conflicting results. We performed a meta-analysis to assess the role of thiopurines for this indication.

Methods

We performed a systematic search of PubMed, Web of Science, EMBASE and Cochrane to identify studies reporting colorectal neoplasm from IBD patients treated with thiopurines and conducted a meta-analysis of pooled relative risk (RR) using the random effects model.

Results

Nine case-control and ten cohort studies fulfilled the inclusion criteria. The use of thiopurines was associated with a statistically significant decreased incidence of colorectal neoplasm (summary RR=0.71, 95% CI=0.54–0.94, p=0.017), even after adjustment for duration and extent of the disease, but there was high heterogeneity among studies (I 2=68.0%, p<0.001). The RR of advanced neoplasm (high-grade dysplasia and cancer) was 0.72 (95%CI=0.50–1.03, p=0.070) and that of cancer was 0.70 (95% CI=0.46–1.09, p=0.111) for thiopurine-treated patients. Heterogeneity of the studies was affected by the sample size (</≥100 cases) and whether the patients had longstanding colitis (≥7 years).

Conclusion

The current meta-analysis revealed that thiopurines had a chemopreventive effect of colorectal neoplasms and a tendency of reducing advanced colorectal neoplasms in IBD. Due to the heterogeneity of included studies, these results should be interpreted with caution.  相似文献   
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