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121.
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Vitamin D is well known for its regulatory role in calcium and phosphate homeostasis, but its role in muscle mass and strength during growth remains inconclusive. We explored the association of serum 25-hydroxyvitamin D (25(OH)D) with muscle development in girls from 11 to 18-years old. Whole body lean tissue mass (LMWB), appendicular lean mass (aLM), muscle cross-sectional area at the lower leg (mCSA), maximal voluntary contraction of elbow flexors (MVCelbow) and knee extensors (MVCknee) were assessed in 217 girls aged 10–13 years (at baseline), 215 in 2-year and 226 in 7.5-year follow-up. Serum concentration of 25(OH)D and intact parathyroid hormone (PTH) were analyzed retrospectively and girls were categorized according to their 25(OH)D levels (consistently insufficient 25(OH)D GLL <50 nmol/l and consistently sufficient GHH >50 nmol/l from baseline to 7-year follow-up). We found that 25(OH)D level declined until menarche (p<0.05) while LMWB, aLM, mCSA, MVCelbow and MVCknee continued to increase (p<0.001 for all) post menarche. At pre-menarche, the GLL (n = 34) had higher LMWB and aLM than the GHH (n = 21, p<0.05), while post-menarche the GHH (n = 15) had a greater catch-up gain in LMWB (p = 0.004), aLM (p = 0.001) and mCSA (p = 0.027) compared to the GLL (n = 65) over the first 2-year period. At the age of 18, no differences in muscle mass/strength between the low (n = 151) and high (n = 77) levels of 25(OH)D groups were found. This finding was independent of vitamin D receptor genotype and other confounders. In conclusion, our results showed that levels of 25(OH)D have no significant negative influence on the development of muscle mass and strength during pubertal growth both with longitudinal and cross-sectional comparison. On the contrary, our results suggest that the temporary negative association between 25(OH)D and muscle mass arises as a consequence of fast growth prior to menarche, and this negative association is diminished through catch-up growth after menarche.  相似文献   
124.
In addition to being an important mediator of migration and invasion of tumor cells, β3 integrin can also enhance TGF-β1 signaling. However, it is not known whether β3 might influence the induction of metastatic phenotype of tumor cells, especially non-metastatic tumor cells which express low level of β3. Here we report that H2O2 and HOCl, the reactive oxygen species produced by neutrophils, could cooperate with TGF-β1 to induce metastatic phenotype of non-metastatic hepatocellular carcinoma (HCC) cells. TGF-β1/H2O2/HOCl, but not TGF-β1 or H2O2/HOCl, induced β3 expression by triggering the enhanced activation of p38 MAPK. Intriguingly, β3 in turn promoted TGF-β1/H2O2/HOCl-mediated induction of metastatic phenotype of HCC cells by enhancing TGF-β1 signaling. β3 promoted TGF-β1/H2O2/HOCl-induced expression of itself via positive feed-back effect on p38 MAPK activation, and also promoted TGF-β1/H2O2/HOCl-induced expression of α3 and SNAI2 by enhancing the activation of ERK pathway, thus resulting in higher invasive capacity of HCC cells. By enhancing MAPK activation, β3 enabled TGF-β1 to augment the promoting effect of H2O2/HOCl on anoikis-resistance of HCC cells. TGF-β1/H2O2/HOCl-induced metastatic phenotype was sufficient for HCC cells to extravasate from circulation and form metastatic foci in an experimental metastasis model in nude mice. Inhibiting the function of β3 could suppress or abrogate the promoting effects of TGF-β1/H2O2/HOCl on invasive capacity, anoikis-resistance, and extravasation of HCC cells. These results suggest that β3 could function as a modulator to promote TGF-β1/H2O2/HOCl-mediated induction of metastatic phenotype of non-metastatic tumor cells, and that targeting β3 might be a potential approach in preventing the induction of metastatic phenotype of non-metastatic tumor cells.  相似文献   
125.

Background

Diabetic patients on peritoneal dialysis (PD) have lower survival and are more likely complicated with inflammation than their non-diabetic counterparts. Here, we explored the interaction effects between diabetes and inflammation on the survival of PD patients.

Methods

Overall, 2,264 incident patients were enrolled from a retrospective cohort study in China. Patients were grouped according to the baseline levels of high-sensitive C-reactive protein (hsCRP, ≤3 mg/L or >3 mg/L) or serum albumin (SA, ≥38 g/L or <38 g/L). Then, several multivariable adjusted stratified Cox regression models were constructed for these groups to explore the predicted role of diabetes on all-cause or cardiovascular death under inflammatory or non-inflammatory conditions.

Results

Diabetics on PD were more likely to have inflammation than non-diabetics on PD, and they presented with elevated hsCRP (52.7% vs. 47.3%, P = 0.03) or decreased SA (77.9% vs. 62.7%, P < 0.001) levels. After stratification by size of center and controlling for confounding factors, diabetes was found to predict all-cause death in patients with hsCRP >3 mg/L or SA <38 g/L but not in patients with hsCRP ≤3 mg/L or SA ≥38 g/L. Similarly, the presence of diabetes was an indication of cardiovascular death in patients with hsCRP >3 mg/L or SA <38 g/L. However, if further adjusted by baseline cardiovascular disease, the predicted role of diabetes on death related to cardiovascular disease in patients with SA <38 g/L disappeared.

Conclusion

Diabetic patients could do as well as non-diabetic patients without inflammation on peritoneal dialysis. Active strategies should be implemented to improve inflammation status in diabetic patients on PD.  相似文献   
126.

Background

In China, the rapid rate of population aging and changes in the prevalence of disability among elderly people could have significant effects on the demand for long-term care. This study aims to describe the urban-rural differences in use and cost of long-term care of the disabled elderly and to explore potential influencing factors.

Methods

This study uses data from a cross-sectional survey and a qualitative investigation conducted in Zhejiang province in 2012. The participants were 826 individuals over 60 years of age, who had been bedridden or suffered from dementia for more than 6 months. A generalized linear model and two-part regression model were applied to estimate costs, with adjustment of covariates.

Results

Pensions provide the main source of income for urban elderly, while the principal income source for rural elderly is their family. Urban residents spend more on all services than do rural residents. Those who are married spend less on daily supplies and formal care than the unmarried do. Age, incapacitation time, comorbidity number, level of income, and bedridden status influence spending on medical care (β=-0.0316, -0.0206, 0.1882, 0.3444, and -0.4281, respectively), but the cost does not increase as the elderly grow older. Urban residents, the married, and those with a higher income level tend to spend more on medical equipment. Urban residence and living status are the two significant factors that affect spending on personal hygiene products.

Conclusions

The use of long-term care services varies by living area. Long-term care of the disabled elderly imposes a substantial burden on families. Our study revealed that informal care involves huge opportunity costs to the caregivers. Chinese policy makers need to promote community care and long-term care insurance to relieve the burden of families of disabled elderly, and particular attention should be given to the rural elderly.  相似文献   
127.

Background

Migration is a major challenge to tuberculosis (TB) control worldwide. TB treatment requires multiple drugs for at least six months. Some TB patients default before completing their treatment regimen, which can lead to ongoing infectiousness and drug resistance.

Methods

We conducted a retrospective analysis of 29,943 active TB cases among urban migrants that were reported between 2000 to 2008 in Shanghai, China. We used logistic regression models to identify factors independently associated with treatment defaults in TB patients among urban migrants during 2005-2008.

Results

Fifty-two percent of the total TB patients reported in Shanghai during the study period were among urban migrants. Three factors increased the odds of a treatment default: case management using self-administered therapy (OR, 5.84, 95% CI, 3.14-10.86, p<0.0005), being a retreatment case (OR, 1.47, 95% CI, 1.25-1.71, p<0.0005), and age >60 years old (OR, 1.33, 95% CI, 1.05-1.67, p=0.017). The presence of a cavity in the initial chest radiograph decreased the odds for a treatment default (OR, 0.87, 95% CI, 0.77-0.97, p=0.015), as did migration from central China (OR, 0.85, 95% CI, 0.73-0.99, p=0.042), case management by family members (OR, 0.73, 95% CI 0.66-0.81, p<0.0005), and the combination of case detection by a required physical exam and case management by health care staff (OR, 0.64, 95% CI, 0.45-0.93, p=0.019).

Conclusion

Among TB patients who were urban migrants in Shanghai, case management using self-administered therapy was the strongest modifiable risk factor that was independently associated with treatment defaults. Interventions that target retreated TB cases could also reduce treatment defaults among urban migrants. Health departments should develop effective measures to prevent treatment defaults among urban migrants, to ensure completion of therapy among urban migrants who move between cities and provinces, and to improve reporting of treatment outcomes.  相似文献   
128.
This prospective study compares different clinical characteristics and outcomes of patients with two types of sacral extradural spinal meningeal cysts (SESMC) undergoing different means of surgical excision. Using the relationship between the cysts and spinal nerve roots fibers (SNRF) as seen under microscope, SESMCs were divided into two types: cysts with SNRF known as Tarlov cysts and cysts without. The surgical methods were tailored to the different types of SESMCs. The improved Japanese Orthopedic Association (IJOA) scoring system was used to evaluate preoperative and postoperative neurological function of the patients. Preoperative IJOA scores were 18.5±1.73, and postoperative IJOA scores were 19.6±0.78. The difference between preoperative and postoperative IJOA scores was statistically significant (t = -4.52, p = 0.0001), with a significant improvement in neurological function after surgery. Among the improvements in neurological functions, the most significant was sensation (z=-2.74, p=0.006), followed by bowel/bladder function (z=-2.50, p=0.01). There was a statistically significant association between the types of SESMC and the number (F=12.57, p=0.001) and maximum diameter (F=8.08, p=0.006) of the cysts. SESMC with SNRF are often multiple and small, while cysts without SNRF tend to be solitary and large. We advocate early surgical intervention for symptomatic SESMCs in view of significant clinical improvement postoperatively.  相似文献   
129.

Purpose

To determine the optimal standardized uptake value (SUV) of 18F-fluorodeoxyglucose (18F-FDG) for positron emission tomography (PET) imaging, at which the PET-defined gross tumor volume (GTVPET) best matches with the pathological volume (GTVPATH) in the cervical cancer.

Materials and Methods

Ten patients with the cervical cancer who underwent surgery were enrolled in this study. The excised specimens were processed for whole-mount serial sections and H-E staining. The tumor borders were outlined in sections under a microscope, histopathological images were scanned and the GTVPATH calculated. The GTVPET was delineated automatically by using various percentages relative to the maximal SUV and absolute SUV. The optimal threshold SUV was further obtained as the value at which the GTVPET best matched with the GTVPATH.

Results

An average of 85±10% shrinkage of tissue was observed after the formalin fixation. The GTVPATH was 13.38±2.80 cm3 on average. The optimal threshold on percentile SUV and absolute SUV were 40.50%±3.16% and 7.45±1.10, respectively. The correlation analysis showed that the optimal percentile SUV threshold was inversely correlated with GTVPATH (p<0.05) and tumor diameter (p<0.05). The absolute SUV was also positively correlated with SUVmax (p<0.05).

Conclusion

The pathological volume could provide the more accurate tumor volume. The optimal SUV of FDG for PET imaging by use of GTVPATH as standard for cervical cancer target volume delineation was thus determined in this study, and more cases are being evaluated to substantiate this conclusion.  相似文献   
130.

Objectives

Follicular helper T (Tfh) cells exert an important role in autoimmune diseases. Whether it might be involved in type 1 diabetes (T1D) is unknown. Our aim was to investigate the role of Tfh cells in patients with T1D and the effect of anti-CD20 monoclonal antibody (rituximab) on Tfh cells from T1D patients.

Patients and Methods

Fifty-four patients with T1D and 37 healthy controls were enrolled in the current study. 20 of those patients were treated with rituximab. The frequencies of circulating CD4+CXCR5+ICOS+T cells were analyzed by flow cytometry. The serum autoantibodies were detected by radioligand assay. The levels of IL-21, IL-6 and BCL-6 were assessed using ELISA and/or real-time PCR.

Results

Increased frequencies of circulating Tfh cells together with enhanced expression of IL-21 were detected in patients. The correlation between the frequencies of circulating Tfh cells and the serum autoantibodies or C-peptide level was comfirmed. After rituximab therapy, follow-up analysis demonstrated that the frequencies of circulating Tfh cell and serum IA2A were decreased. The levels of IL-21, IL-6 and Bcl-6 mRNA were decreased after treatment. Furthermore, beta cell function in 10 of 20 patients was improved.

Conclusions

These data indicate Tfh cells may participate in the T1D-relatede immune responses and B cells might play a role in the development of Tfh responses in the disease progression.  相似文献   
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