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91.
92.
Metabolic Brain Disease - Cholecalciferol deficiency has been associated with stress-related psychiatric disorders, particularly depression. Therefore, the present study investigated the...  相似文献   
93.
Schwannomatosis is characterized by the development of multiple non-vestibular, non-intradermal schwannomas. Constitutional inactivating variants in two genes, SMARCB1 and, very recently, LZTR1, have been reported. We performed exome sequencing of 13 schwannomatosis patients from 11 families without SMARCB1 deleterious variants. We identified four individuals with heterozygous loss-of-function variants in LZTR1. Sequencing of the germline of 60 additional patients identified 18 additional heterozygous variants in LZTR1. We identified LZTR1 variants in 43% and 30% of familial (three of the seven families) and sporadic patients, respectively. In addition, we tested LZTR1 protein immunostaining in 22 tumors from nine unrelated patients with and without LZTR1 deleterious variants. Tumors from individuals with LZTR1 variants lost the protein expression in at least a subset of tumor cells, consistent with a tumor suppressor mechanism. In conclusion, our study demonstrates that molecular analysis of LZTR1 may contribute to the molecular characterization of schwannomatosis patients, in addition to NF2 mutational analysis and the detection of chromosome 22 losses in tumor tissue. It will be especially useful in differentiating schwannomatosis from mosaic Neurofibromatosis type 2 (NF2). However, the role of LZTR1 in the pathogenesis of schwannomatosis needs further elucidation.  相似文献   
94.
PURPOSE: Staphylococcus aureus is a common cause of bacteremia and of native valve infective endocarditis. However, the risk of endocarditis in patients with a prosthetic valve who develop S. aureus bacteremia is unclear. The aim of this study was to define the risk of prosthetic valve endocarditis in patients with S. aureus bacteremia. SUBJECTS AND METHODS: All patients with a prosthetic valve or ring who developed S. aureus bacteremia during the 94-month study period were prospectively evaluated. The modified Duke criteria were used for the diagnosis of endocarditis. Patients were followed up for 12 weeks after the initial diagnosis of S. aureus bacteremia. RESULTS: The overall rate of definite prosthetic valve endocarditis among the study patients was 26/51 (51%). The risk of endocarditis was similar in patients with late (>or=12 months after valve implantation) vs. early S. aureus bacteremia (<12 months after prosthetic valve implantation) (50% vs. 52%, P=1.0), mitral vs. aortic prostheses (62% vs. 48%, P=0.24), and mechanical vs. bioprosthetic valves (62% vs. 44%, P=0.29). The 12-week mortality was higher among patients with definite vs. possible endocarditis (62% vs. 28%, P=0.019). CONCLUSION: In this investigation, approximately half of all patients with prosthetic valves who developed S. aureus bacteremia had definite endocarditis. The risk of endocarditis was independent of the type, location, or age of the prosthetic valve. The mortality of prosthetic valve endocarditis is high. All patients with a prosthetic valve who develop S. aureus bacteremia should be aggressively screened and followed for endocarditis.  相似文献   
95.
In 1999, we began a community-based randomized controlled prevention trial in Chennai, which aims to test the efficacy of HIV prevention messages disseminated through members of an individual's social group called community popular opinion leaders, or CPOLs. We targeted patrons of 100 bars or wine shops in the city of Chennai, India. In this article we report on the process of development of an HIV prevention intervention for wine shop patrons. First, we conducted detailed ethnography to understand social norms and CPOL and social network characteristics, including 41 in-depth interviews among wine shop patrons and gatekeepers. Second, we tailored a generic HIV education training manual to appropriately address the needs of Chennai wine shop patrons. Field-testing involved 16 focus groups with wine shop patrons and 12 sessions of participant observations in wine shops. Finally, we piloted the intervention to determine the appropriateness of the training program and its content among wine shop patrons. Our ethnographic data indicated that wine shops are a common meeting place for men. We were able to identify CPOLs influential in these settings and train them to deliver appropriate prevention messages to their close friends and associates. We found that HIV prevention messages in this population need to dispel misperceptions about HIV transmission, provide strategies and skills to adopt and sustain condom use, and target the role of alcohol in sexual behavior. We outline specific lessons we learned in intervention development in this population.  相似文献   
96.
OBJECTIVE: Insulin-like growth factor binding protein-3 (IGFBP-3) has been shown to exhibit diverse biological actions, including IGF-independent effects on cell growth and cell death. Here we report that IGFBP-3 sensitizes prostate cancer cells to interferon-gamma (IFN-gamma)-induced apoptosis and inhibition of cell proliferation. DESIGN: The cell growth or cell death of prostate cells in response to the treatments of IGFBPs and/or IFN-gamma was measured, and the signaling pathways mediating these actions assessed. RESULTS: Cell proliferation was minimally affected when M12 prostate cancer cells were treated with exogenous IGFBP-3 (1-5 microg/ml), IGFBP-1 (1-5 microg/ml) or IFN-gamma (20 U/ml). However, strong inhibition of cell growth and significant apoptosis were observed when M12 cells were co-treated with IGFBP-3 and IFN-gamma, but not with IGFBP-1 and IFN-gamma. These effects were IGF-independent and appear not to require intracellular localization of IGFBP-3, as similar results were obtained with mutants of IGFBP-3 that either could not bind IGF or has impaired ability to be internalized. Further analyses revealed that IGFBP-3, but not IGFBP-1, could significantly enhance the weak tyrosine phosphorylation of STAT1 induced by IFN-gamma (20 U/ml) alone. The IGFBP-3-promoted apoptosis in the presence of IFN-gamma could also be abrogated by blockade of the mTOR pathway with its pharmacological inhibitors, LY294002 or rapamycin. CONCLUSIONS: These results demonstrated that in a cancer cell line not responsive to exogenous IGFBP-3 alone, IGFBP-3 sensitized the cells to the anti-proliferative, proapoptotic actions of IFN-gamma through an IGF-independent, STAT1- and mTOR-dependent mechanism.  相似文献   
97.
Protein synthesis initiation in reticulocyte lysates is inhibited by heme deficiency, low levels of double-stranded RNA (dsRNA), oxidized glutathione (GSSG), or the purified kinase (HRI) that acts on the alpha polypeptide of eukaryotic initiation factor 2 (eIF-2alpha). The phosphoprotein profiles produced in lysates in response to these various conditions have been monitored directly in lysates after labeling for brief periods with pulses of [gamma-(32)P]ATP. The [(32)P]phosphoprotein profiles were analyzed by electrophoresis in sodium dodecyl sulfate/polyacrylamide slab gels under conditions in which the HRI and eIF-2alpha polypeptides were clearly distinguished. All four modes of inhibition produced a rapid phosphorylation of eIF-2alpha compared to control lysates, which displayed little or no phosphorylation of eIF-2alpha. In heme-deficient lysates, phosphorylation of eIF-2alpha occurred rapidly both before and after the shut-off of protein synthesis; the delayed addition of hemin to these lysates resulted in a decrease in the phosphorylation of eIF-2alpha and the subsequent restoration of protein synthesis. These data suggest that rapid turnover of phosphate occurs at the site(s) of eIF-2alpha phosphorylation. In lysates inhibited by heme deficiency, GSSG, or added HRI, the phosphorylation of eIF-2alpha was accompanied by the rapid in situ phosphorylation of HRI. The inhibition of initiation induced by dsRNA was accompanied by the phosphorylation of eIF-2alpha and a 67,000-dalton polypeptide but not HRI. These observations in situ indicate that (i) the phosphorylation of eIF-2alpha is the critical event in these inhibitions of protein chain initiation, and (ii) the phosphorylation of HRI is associated with its activation in heme deficiency.  相似文献   
98.

Background

The hammock positioning within the incubators simulates the intrauterine environment, however, there is little evidence of its benefits and possible risks.

Objectives

The aim of this study was to assess the effects of hammock positioning on behavioral status, vital signs, and pain in very low birth weight preterm newborns.

Methods

This is a quasi-experimental/case series study in which premature infants (<1500 g) were positioned in supine for one hour in a hammock. The preterm newborns were assessed 10 min before, during (2, 20, 40, and 60 min), and 10 min after hammock positioning with the Brazelton Neonatal Behavioral Assessment Scale, vital signs and pain by the Neonatal Facial Coding System.

Results

28 preterm infants between 28 and 36 weeks of gestational age were evaluated. Regarding the behavioral state, the preterm newborns progressively evolved to light or deep sleep during hammock positioning. There was a statistically significant reduction of the heart and respiratory rate from 2 to 60th minute in a hammock, which was maintained after the positioning. The oxygen saturation remained within normal values. No changes in pain scores were observed.

Conclusion

The hammock positioning can be considered a safe method of positioning that can be used to reduce the stress levels in very low birth weight preterm newborns. We did not observe worsening in either pain or vital signs.  相似文献   
99.
100.
Objective Analysis of narrative (text) data from electronic health records (EHRs) can improve population-scale phenotyping for clinical and genetic research. Currently, selection of text features for phenotyping algorithms is slow and laborious, requiring extensive and iterative involvement by domain experts. This paper introduces a method to develop phenotyping algorithms in an unbiased manner by automatically extracting and selecting informative features, which can be comparable to expert-curated ones in classification accuracy.Materials and methods Comprehensive medical concepts were collected from publicly available knowledge sources in an automated, unbiased fashion. Natural language processing (NLP) revealed the occurrence patterns of these concepts in EHR narrative notes, which enabled selection of informative features for phenotype classification. When combined with additional codified features, a penalized logistic regression model was trained to classify the target phenotype.Results The authors applied our method to develop algorithms to identify patients with rheumatoid arthritis and coronary artery disease cases among those with rheumatoid arthritis from a large multi-institutional EHR. The area under the receiver operating characteristic curves (AUC) for classifying RA and CAD using models trained with automated features were 0.951 and 0.929, respectively, compared to the AUCs of 0.938 and 0.929 by models trained with expert-curated features.Discussion Models trained with NLP text features selected through an unbiased, automated procedure achieved comparable or slightly higher accuracy than those trained with expert-curated features. The majority of the selected model features were interpretable.Conclusion The proposed automated feature extraction method, generating highly accurate phenotyping algorithms with improved efficiency, is a significant step toward high-throughput phenotyping.  相似文献   
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