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1.
Recent studies have emphasized the important role of microRNA (miRNA) clusters and common target genes in disease progression. Despite the known involvement of the miR‐192/215 family in many human diseases, its biological role in Hirschsprung disease (HSCR) remains undefined. In this study, we explored the role of the miR‐192/215 family in the pathogenesis of HSCR. Quantitative real‐time PCR and western blotting measured relative expression levels of miRNAs, mRNAs, and proteins in 80 HSCR patients and 77 normal colon tissues. Targets were evaluated by dual‐luciferase reporter assays, and the functional effects of miR‐192/215 on human 293T and SH‐SY5Y cells were detected by the Transwell assay, CCK8 assay and flow cytometry. MiR‐192/215 was significantly down‐regulated in HSCR tissue samples, and their knockdown inhibited cell migration and proliferation in the human 293T and SH‐SY5Y cell lines. Nidogen 1 (NID1) was confirmed as a common target gene of miR‐192/215 by dual‐luciferase reporter gene assay and its expression was inversely correlated with that of miR‐192/215 in tissue samples and cell lines. Silencing of NID1 could rescue the extent of the suppressing effects by miR‐192/215 inhibitor. The down‐regulation of miR‐192/215 may contribute to HSCR development by targeting NID1.

  相似文献   

2.
It was found that S-adenosylmethionine (SAM) could effectively improve avermectin titer with 30–60 μg/mL addition to FH medium. To clearly elucidate the mechanism of SAM on intracellular metabolites of Streptomyces avermitilis, a GC–MS-based comparative metabolomics approach was carried out. First, 230 intracellular metabolites were identified and 14 of them remarkably influenced avermectin biosynthesis were discriminative biomarkers between non-SAM groups and SAM-treated groups by principal components analysis (PCA) and partial least squares (PLS). Based on further key metabolic pathway analyses, these biomarkers, such as glucose, oxaloacetic acid, fatty acids (in soybean oil), threonine, valine, and leucine, were identified as potentially beneficial precursors and added in medium. Compared with single-precursor feeding, the combined feeding of the precursors and SAM markedly increased the avermectin titer. The co-feeding approach not only directly verified our hypothesis on the mechanism of SAM by comparative metabolomics, but also provided a novel strategy to increase avermectin production.  相似文献   
3.
Mutations in CLN3 gene cause juvenile neuronal ceroid lipofuscinosis (JNCL or Batten disease), an early-onset neurodegenerative disorder that is characterized by the accumulation of ceroid lipofuscin within lysosomes. The function of the CLN3 protein remains unclear and is presumed to be related to Endoplasmic reticulum (ER) stress. To investigate the function of CLN3 in the ER stress signaling pathway, we measured proliferation and apoptosis in cells transfected with normal and mutant CLN3 after treatment with the ER stress inducer tunicamycin (TM). We found that overexpression of CLN3 was sufficient in conferring increased resistance to ER stress. Wild-type CLN3 protected cells from TM-induced apoptosis and increased cell proliferation. Overexpression of wild-type CLN3 enhanced expression of the ER chaperone protein, glucose-regulated protein 78 (GRP78), and reduced expression of the proapoptotic protein CCAAT/-enhancer-binding protein homologous protein (CHOP). In contrast, overexpression of mutant CLN3 or siRNA knockdown of CLN3 produced the opposite effect. Together, our data suggest that the lack of CLN3 function in cells leads to a failure of management in the response to ER stress and this may be the key deficit in JNCL that causes neuronal degeneration.  相似文献   
4.

Objective

To evaluate the association between chronic opioid use for non-cancer pain and fracture risk by conducting a meta-analysis of cohort studies.

Methods

Cohort studies were identified by searching PubMed and EMBASE from their inception to July 2014. A fracture was considered an endpoint. The information was extracted by two authors independently. When the heterogeneity was significant, a random-effects model was used to calculate the overall pooled risk estimates.

Results

Eight cohort studies were included in the final meta-analysis. On the basis of the Newcastle-Ottawa Scale (NOS), six studies were considered to be of high quality. The overall combined relative risk for the use of opioids and fractures was 1.88 (95% confidence interval [CI] 1.51-2.34). A subgroup analysis revealed the sources of heterogeneity. The sensitivity analysis indicated stable results, and no publication bias was observed.

Conclusions

This meta-analysis of cohort studies demonstrates that opioids significantly increase the risk of fractures.  相似文献   
5.

Objective

This study aimed to investigate the relationship between serum vitamin D level and carotid intima-media thickness (C-IMT) in Chinese postmenopausal women.

Methods

Nine hundred and twenty six Chinese postmenopausal women without carotid artery plaque or history of cardiovascular disease were selected for analysis. Measurements of serum 25 hydroxyvitamin D3 (25(OH)D3) concentration and C-IMT were made by electrochemiluminescence immunoassay and B-mode ultrasound, respectively. Trend analysis was conducted according to tertiles of C-IMT.

Results

The median serum 25(OH)D3 level was 11.03 ng/mL, with an interquartile range of 8.22–14.70. A decreasing trend of serum 25(OH)D3 level was accompanied by increased C-IMT tertiles (P for trend = 0.001). Correlation analysis found an inverse relationship between serum 25(OH)D3 level and C-IMT (r = –0.113, P = 0.001). After adjustment for confounding factors, multiple regression analysis showed that serum 25(OH)D3 level independently and negatively associated with C-IMT (Standard β = –0.112, P < 0.001). Moreover, the inverse correlation of serum 25(OH)D3 with C-IMT was also found in a subgroup of women with normal glucose tolerance, blood pressure and body mass index, and without undergoing lipid-lowering therapy (standard β = –0.140, P = 0.018).

Conclusions

Serum 25(OH)D3 level was inversely correlated with C-IMT in Chinese postmenopausal women.  相似文献   
6.
7.
ObjectiveWe investigated whether glutamate, NMDA receptors, and eukaryote elongation factor-2 kinase (eEF-2K)/eEF-2 regulate P-glycoprotein expression, and the effects of the eEF-2K inhibitor NH125 on the expression of P-glycoprotein in rat brain microvessel endothelial cells (RBMECs).MethodsCortex was obtained from newborn Wistar rat brains. After surface vessels and meninges were removed, the pellet containing microvessels was resuspended and incubated at 37°C in culture medium. Cell viability was assessed by the MTT assay. RBMECs were identified by immunohistochemistry with anti-vWF. P-glycoprotein, phospho-eEF-2, and eEF-2 expression were determined by western blot analysis. Mdr1a gene expression was analyzed by RT-PCR.ResultsMdr1a mRNA, P-glycoprotein and phospho-eEF-2 expression increased in L-glutamate stimulated RBMECs. P-glycoprotein and phospho-eEF-2 expression were down-regulated after NH125 treatment in L-glutamate stimulated RBMECs.ConclusionseEF-2K/eEF-2 should have played an important role in the regulation of P-glycoprotein expression in RBMECs. eEF-2K inhibitor NH125 could serve as an efficacious anti-multidrug resistant agent.  相似文献   
8.
There has been a rapid increase in the incidence of prostate cancer in China, especially in areas with boosted economic development. In this study, we analyzed the pathological features of a contemporary series of radical prostatectomy cases. A total of 230 consecutive, whole-mounted radical prostatectomy specimens collected from 2012 to 2014 were reviewed. The median age of the patients was 68 years, and 64.3% of patients presented with prostate specific antigen alone. Pathological examination indicated that a high proportion (77.4%) of patients had intermediate- or high-risk disease according to the Cancer of the Prostate Risk Assessment Post-Surgical score. After surgery, only 28 patients met the criteria for active surveillance (organ-confined Gleason ≥6 disease). The Prostate Cancer Research International Active Surveillance criteria achieved a sensitivity of 57.1% and a specificity of 98.0% for identifying candidates. The probability of Gleason score upgrading was 24.8% in the entire group and 59.0% in biopsy-confirmed Gleason ≥6 disease. The predominant tumor was located in the transition zone in 14.8% of cases, while only three patients (1.3%) had a predominant tumor located in the anterior region. Patients with transition zone-predominant tumor were likely to have been referred with urinary symptoms and high prostate specific antigen levels. The results of this study highlight the contemporary pathological features of localized prostate cancer in urban China. There was an increased trend towards asymptomatic cases, though most patients had intermediate- or high-risk disease and were suitable for definitive treatment. The low prevalence of dominant cancer in the anterior region may reflect race-based pathological differences.  相似文献   
9.
BackgroundPostoperative delirium is one of the most common postoperative complications in geriatric patients. Mini-mental state examination (MMSE) assesses cognitive function in patients and is associated with postoperative delirium. However, whether there is an age-dependent relationship between preoperative MMSE score and postoperative delirium remains unknown.MethodsWe therefore set out to investigate the association between preoperative MMSE score and postoperative delirium in young-old (≤80 year-old, 75.46±4.69 years, 27.0% male, n = 63) and old-old (>80 year-old, 84.51±3.46 years, 20.9% male, n = 67) participants, who had repairs of hip fractures under general anesthesia. The Confusion Assessment Method and Memorial Delirium Assessment Scale were administrated before surgery, and on the first, second and fourth days after surgery, to assess the incidence and severity of the delirium, respectively. A receiver operating characteristic curve analysis was used to calculate the optimal cutoff score of MMSE in predicting postoperative delirium.ResultsThirty-four (26.2%) of 130 patients (80.12±6.12 years, 23.8% male) developed postoperative delirium. Preoperative MMSE scores were negatively associated with higher incidences and greater severity of postoperative delirium. The optimal cutoff scores of MMSE associated with postoperative delirium for young-old and old-old participants were 18.4 and 21.4, with a sensitivity of 60% and 83.8%, and a specificity of 92.5% and 62.8%, respectively.ConclusionThe data demonstrated the optimal cutoff score of MMSE associated with postoperative delirium in young-old adults might be lower than that in old-old adults. Pending further investigation, these findings suggest that the association between preoperative MMSE score and postoperative delirium is age-dependent.  相似文献   
10.
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