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951.

Background

Oral health has been found to be associated with cognitive function in basic research and epidemiology studies. Most of these studies had no comprehensive clinical diagnosis on cognitive function. This study firstly reported the association between tooth loss and cognitive function among Chinese older population.

Methods

The study included 3,063 community dwelling older adults aged 60 or above from the Shanghai Aging Study. Number of teeth missing was obtained from self-reporting questionnaire and confirmed by trained interviewers. Participants were diagnosed as “dementia”, “mild cognitive impairment (MCI)”, or “cognitive normal” by neurologists using DSM-IV and Petersen criteria. Multivariate logistic regression model was applied to examine the association between number of teeth missing and cognitive function.

Results

The study participants had an average of 10.2 teeth lost. Individuals with dementia lost 18.7 teeth on average, much higher than those with MCI (11.8) and cognitive normal (9.3) (p<0.001). After adjusted for sex, age, education year, living alone, body mass index, cigarette smoking, alcohol drinking, anxiety, depression, heart disease, hypertension, diabetes, and APOE-ε4, tooth loss of >16 were significantly associated with dementia with an OR of 1.56 (95%CI 1.12-2.18).

Conclusion

Having over 16 missing teeth was associated with severe cognitive impairment among Chinese older adults. Poor oral health might be considered as a related factor of neurodegenerative symptom among older Chinese population.  相似文献   
952.

Introduction

To evaluate the prognostic value of gross tumor volume (TV) in patients with locally recurrent, nonmetastatic nasopharyngeal carcinoma.

Methods

Between 2001 and 2012, 291 consecutive patients with locally recurrent, nonmetastatic nasopharyngeal carcinoma underwent salvage IMRT were retrospectively reviewed. The correlations between TV and recurrent T classification were analyzed. Survival analyses were performed. Receiver operating characteristic (ROC) curves were calculated to identify cut-off point of TV. The Akaike information criterion and Harrell’s concordance index (c-index) were utilized to test the prognostic value.

Results

The median TV significantly increased with advancing recurrent T classification (P<0.001). The 5-year overall survival rate was 33.2% for the entire cohort. On multivariate analysis, TV was an independent negative prognostic factor for distant metastasis-free survival (hazard ratio =1.013, P =0.003), overall survival (hazard ratio = 1.015, P<0.001) and toxicity-related death (hazard ratio = 1.014, P<0.001). The 5-year overall survival rates were 63.1% and 20.8% for patients with a TV < 22 cm3 and TV ≥22 cm3, respectively (P < 0.001). In patient with TV <22 cm3, locoregional failure is the leading cause of death. In patients with TV≥22 cm3, distant metastasis rate is higher and occurred within short term after local recurrence; meanwhile, radiation-induced injuries became more common and led to half of deaths in this group. The Akaike information criterion and c-index analyses indicated that the predictive ability of recurrent T classification improved when combined with TV.

Conclusions

Our data suggests TV is a significant prognostic factor for predicting the distant metastasis, overall survival and toxicity-related death of patients with locally recurrent, nonmetastatic nasopharyngeal carcinoma after salvage IMRT. TV should be considered when designing personalized salvage treatments for these patients. For patients with bulky local recurrent tumor, radiation may need to be de-emphasized in favor of systemic treatment or best supportive care.  相似文献   
953.
Epithelial to mesenchymal transition (EMT) promotes cellular motility, invasiveness and metastasis during embryonic development and tumorigenesis. Transforming growth factor-β (TGF-β) signaling pathway is a key regulator of EMT. A lot of evidences suggest that this process is Smad3-dependent. Herein we showed that exposure of aspc-1 and panc-1 pancreatic cancer cells to TGF-β1 resulted in characteristic morphological alterations of EMT, and enhancement of cell motility and gemcitabine (Gem) resistance along with an up-regulation of EMT markers genes such as vimentin, N-cadherin, MMP2 and MMP9. Naringenin (Nar) down-regulated EMT markers expression in both mRNA and protein levels by inhibiting TGF-β1/Smad3 signal pathway in the pancreatic cancer cells. Consequently, Nar suppressed the cells migration and invasion and reversed their resistance to Gem.  相似文献   
954.
Human parainfluenza virus type 3 (HPIV3) can cause severe respiratory tract diseases in infants and young children, but no licensed vaccines or antiviral agents are currently available for treatment. Fusing the viral and target cell membranes is a prerequisite for its entry into host cells and is directly mediated by the fusion (F) protein. Although several domains of F are known to have important effects on regulating the membrane fusion activity, the roles of the DI-DII linker (residues 369–374) of the HPIV3 F protein in the fusogenicity still remains ill-defined. To facilitate our understanding of the role of this domain might play in F-induced cell-cell fusion, nine single mutations were engineered into this domain by site-directed mutagenesis. A vaccinia virus-T7 RNA polymerase transient expression system was employed to express the wild-type or mutated F proteins. These mutants were analyzed for membrane fusion activity, cell surface expression, and interaction between F and HN protein. Each of the mutated F proteins in this domain has a cell surface expression level similar to that of wild-type F. All of them resulted in a significant reduction in fusogenic activity in all steps of membrane fusion. Furthermore, all these fusion-deficient mutants reduced the amount of the HN-F complexes at the cell surface. Together, the results of our work suggest that this region has an important effect on the fusogenic activity of F.  相似文献   
955.
Piwi proteins and Piwi‐interacting RNAs (piRNAs) repress transposition, regulate translation, and guide epigenetic programming in the germline. Here, we show that an evolutionarily conserved Tudor and KH domain‐containing protein, Tdrkh (a.k.a. Tdrd2), is required for spermatogenesis and involved in piRNA biogenesis. Tdrkh partners with Miwi and Miwi2 via symmetrically dimethylated arginine residues in Miwi and Miwi2. Tdrkh is a mitochondrial protein often juxtaposed to pi‐bodies and piP‐bodies and is required for Tdrd1 cytoplasmic localization and Miwi2 nuclear localization. Tdrkh mutants display meiotic arrest at the zygotene stage, attenuate methylation of Line1 DNA, and upregulate Line1 RNA and protein, without inducing apoptosis. Furthermore, Tdrkh mutants have severely reduced levels of mature piRNAs but accumulate a distinct population of 1′U‐containing, 2′O‐methylated 31–37 nt RNAs that largely complement the missing mature piRNAs. Our results demonstrate that the primary piRNA biogenesis pathway involves 3′→5′ processing of 31–37 nt intermediates and that Tdrkh promotes this final step of piRNA biogenesis but not the ping‐pong cycle. These results shed light on mechanisms underlying primary piRNA biogenesis, an area in which information is conspicuously absent.  相似文献   
956.

Objective

Test whether angiographically-documented changes in percent stenosis and clinical endpoints (coronary-related deaths, myocardial infarctions, stroke, revascularization for worsening ischemia) in the HDL-Atherosclerosis Treatment Study (HATS) were attributable to specific LDL-subclasses.

Methods

Gradient gel electrophoresis of on-study LDL-subclass cholesterol concentrations were measured in 32 placebo, 33 simvastatin-niacin, 38 antioxidant, and 39 simvastatin-niacin & antioxidant treated participants. The prespecified primary end point was the mean change per patient from the initial arteriogram to the final arteriogram in the percent stenosis caused by the most severe lesion in each of the nine proximal coronary segments.

Results

The change in the percent stenosis of the most severe proximal lesions increased in association with higher concentrations of the small LDL subfractions LDL-IIIb (24.2–24.6 nm) and LDL-IVa (23.3–24.1 nm) before (both P = 0.002) and after (P = 0.01 and P = 0.03 respectively) adjustment for treatment group and on-study HDL-cholesterol, LDL-cholesterol, and triglyceride concentrations. The associations appeared specific to lesions with <30% baseline stenosis. When adjusted for age, sex, baseline BMI and cigarette use, the odds for primary clinical endpoints (death from coronary causes, nonfatal myocardial infarction, stroke, or revascularization for worsening ischemia) were significantly greater in subjects with higher on-study LDL-IIIb levels both before (P = 0.01) and after (P = 0.03) adjustment for treatment group and the standard lipid values.

Conclusions

Plasma LDL-IIIb cholesterol concentrations were related to changes in coronary artery stenosis and cardiovascular events in patients with coronary artery disease and low HDL-cholesterol.

Trial Registration

ClinicalTrials.gov NCT00000553  相似文献   
957.

Background

Autism is a neurodevelopmental disorder with a high estimated heritability. ATP2B2, located on human chromosome 3p25.3, encodes the plasma membrane calcium-transporting ATPase 2 which extrudes Ca2+ from cytosol into extracellular space. Recent studies reported association between ATP2B2 and autism in samples from Autism Genetic Resource Exchange (AGRE) and Italy. In this study, we investigated whether ATP2B2 polymorphisms were associated with autism in Chinese Han population.

Methods

We performed a family based association study between five SNPs (rs35678 in exon, rs241509, rs3774180, rs3774179, and rs2278556 in introns) in ATP2B2 and autism in 427 autism trios of Han Chinese descent. All SNPs were genotyped using the Sequenom genotyping platform. The family-based association test (FBAT) program was used to perform association test for SNPs and haplotype analyses.

Results

This study demonstrated a preferential transmission of T allele of rs3774179 to affected offsprings under an additive model (T>C, Z = 2.482, p = 0.013). While C allele of rs3774179 showed an undertransmission from parents to affected children under an additive and a dominant model, respectively (Z = −2.482, p = 0.013; Z = −2.591, p = 0.0096). Haplotype analyses revealed that three haplotypes were significantly associated with autism. The haplotype C-C (rs3774180–rs3774179) showed a significant undertransmission from parents to affected offsprings both in specific and global haplotype FBAT (Z = −2.037, p = 0.042; Global p = 0.03). As for the haplotype constructed by rs3774179 and rs2278556, C-A might be a protective haplotype (Z = −2.206, p = 0.027; Global p = 0.04), while T-A demonstrated an excess transmission from parents to affected offsprings (Z = 2.143, p = 0.032). These results were still significant after using the permutation method to obtain empirical p values.

Conclusions

Our research suggested that ATP2B2 might play a role in the etiology of autism in Chinese Han population.  相似文献   
958.
959.
Tuberculosis is a major cause of mortality and morbidity due to infectious disease. However, current clinical diagnostic methodologies such as PCR, sputum culture, or smear microscopy are not ideal. Antibody-based assays are a suitable alternative but require specific antibodies against a suitable biomarker. Mycolic acid, which has been found in patient sputum samples and comprises a large portion of the mycobacterial cell wall, is an ideal target. However, generating anti-lipid antibodies using traditional hybridoma methodologies is challenging and has limited the exploitation of this lipid as a diagnostic marker. We describe here the isolation and characterization of four anti-mycolic acid antibodies from a nonimmune antibody phage display library that can detect mycolic acids down to a limit of 4.5ng. All antibodies were specific for the methoxy subclass of mycolic acid with weak binding for α mycolic acid and did not show any binding to closely related lipids or other Mycobacterium tuberculosis (Mtb) derived lipids. We also determined the clinical utility of these antibodies based on their limit of detection for mycobacteria colony forming units (CFU). In combination with an optimized alkaline hydrolysis method for rapid lipid extraction, these antibodies can detect 105 CFU of Mycobacterium bovis BCG, a close relative of Mtb and therefore represent a novel approach for the development of diagnostic assays for lipid biomarkers.  相似文献   
960.
3, 5-Diiodothyronine (T2), a natural metabolite of triiodothyronine (T3) from deiodination pathway, can mimic biologic effects of T3 without inducing thyrotoxic effects. Recent studies revealed T3 acted as a protective factor against diabetic nephropathy (DN). Nevertheless, little is known about the effect of T2 on DN. This study was designed to investigate whether and how T2 affects experimental models of DN in vivo and in vitro. Administration of T2 was found to prevent significant decrease in SIRT1 protein expression and activity as well as increases in blood glucose, urine albumin excretion, matrix expansion, transforming growth factor-β1 expression, fibronectin and type IV collagen deposition in the diabetic kidney. Concordantly, similar effects of T2 were exhibited in the cultured rat mesangial cells (RMC) exposed to high glucose and that could be abolished by a known SIRT1 inhibitor, sirtinol. Moreover, enhanced NF-κB acetylation and JNK phosphorylation present in both diabetic rats and high glucose-treated RMC were distinctly dampened by T2. Collectively, these results suggested that T2 was a protective agent against renal damage in diabetic nephropathy, whose action involved regulation of SIRT1.  相似文献   
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