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51.
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Opioids have previously been shown to affect proliferation and differentiation in various neural cell types. In the present study, cultured rat adult hippocampal progenitors (AHPs) were shown to release beta-endorphin. Membrane preparations of AHPs were found to bind [125I]beta-endorphin, and immunoreactivity for mu- and delta-opioid receptors (MORs and DORs), but not for kappa-opioid receptors (KORs), was found on cells in culture. Both DNA content and [3H]thymidine incorporation were reduced after a 48-h incubation with 100 microM naloxone, 10 micro m naltrindole or 10 microM beta-funaltrexamine, but not nor-binaltorphimine, suggesting proliferative actions of endogenous opioids against MORs and DORs on AHPs. Furthermore, analysis of gene and protein expression after incubation with MOR and DOR antagonists for 48 h using RT-PCR and Western blotting suggested decreased signalling through the mitogen-activated protein kinase (MAPK) pathway and lowered levels of genes and proteins that are important in cell cycling. Cultures were incubated with naloxone (10 or 100 microM) for 10 days to study the effects on differentiation. This resulted in an approximately threefold increase in neurogenesis, a threefold decrease in astrogliogenesis and a 50% decrease in oligodendrogenesis. In conclusion, this study suggests that reduced signalling through MORs and DORs decreases proliferation in rat AHPs, increases the number of in vitro-generated neurons and reduces the number of astrocytes and oligodendrocytes in culture.  相似文献   
53.
OBJECTIVE: To provide an overview of the use and impact of written drug information (WDI) on consumers, and to review the literature on the factors influencing the use of WDI by consumers. DATA SOURCES: Relevant articles published in English since the late 1970s were identified based on searches of on-line databases, texts, and cited references in published articles. STUDY SELECTION: Articles reporting findings on the origin, use, and impact of WDI were included. Due to limited literature, articles reporting findings on factors influencing the use of written drug as well as disease information were included. DATA EXTRACTION: Due to the lack of design consistency between studies and the comparatively small volume of work, subjective assessment rather than a criteria-based objective review was deemed more appropriate. DATA SYNTHESIS: To date, research on WDI has focused on its use and impact. WDI has the potential to increase patients' knowledge, compliance, and satisfaction. However, there is also the potential for anxiety or premature cessation of therapy due to fear of possible adverse effects. Multiple factors may potentially influence the use of WDI by consumers including those associated with the written information document (readability, presentation), the patient (health literacy, role of caregiver, demographic factors, health locus of control, coping style, health belief model), and the environment (timing of provision, experience). CONCLUSIONS: WDI has the potential to impact consumers positively and negatively. Although not widely investigated, a number of factors can potentially influence the use of WDI by consumers. The findings of this review can form the basis for much needed further research.  相似文献   
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Predominantly antibody deficiencies (PADs) encompass a heterogeneous group of disorders characterized by low immunoglobulin serum levels in the presence or absence of peripheral B cells. Clinical presentation of affected patients may include recurrent respiratory and gastrointestinal infections, invasive infections, autoimmune manifestations, allergic reactions, lymphoproliferation, and increased susceptibility to malignant transformation. In the last decades, several genetic alterations affecting B-cell development/maturation have been identified as causative of several forms of PADs, adding important information on the genetic background of PADs, which in turn should lead to a better understanding of these disorders and precise clinical management of affected patients. This review aimed to present a comprehensive overview of the known and potentially involved molecules in the etiology of PADs to elucidate the pathogenesis of these disorders and eventually offer a better prognosis for affected patients.  相似文献   
56.
A scanning system for small animal imaging using non-contact, hybrid broadband diffuse optical spectroscopy (ncDOS) and diffuse correlation spectroscopy (ncDCS) is presented. The ncDOS uses a two-dimensional spectrophotometer retrieving broadband (610-900 nm) spectral information from up to fifty-seven source-detector distances between 2 and 5 mm. The ncDCS data is simultaneously acquired from four source-detector pairs. The sample is scanned in two dimensions while tracking variations in height. The system has been validated with liquid phantoms, demonstrated in vivo on a human fingertip during an arm cuff occlusion and on a group of mice with xenoimplanted renal cell carcinoma.OCIS codes: (170.0170) Medical optics and biotechnology, (170.0110) Imaging systems  相似文献   
57.

Purpose

This study aimed to determine effects of community-based healthy lifestyle education on the incidence of metabolic syndrome (MetS) in Tehranian children considering parental factors during a 13-year follow-up.

Methods

This study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS) on 1603 healthy children, aged 8–18 years, who had complete parental data. Parental factors including MetS, education, age, occupation, and smoking were considered to distinguish parental clusters which could potentially predispose children to MetS. Lifestyle interventions were aimed at achieving healthy dietary patterns and increasing physical activity. Cluster analysis and survival Cox model were used to determine potential low and high risk parental clusters and the effect of intervention on the hazard of MetS in children respectively.

Results

In a model adjusted for children’s age and sex, the hazard of the MetS incidence was 36% higher in children from high-risk parental cluster than those from low-risk parental cluster (HR = 1.36, 95% CI = 1.07–1.73). Moreover, the intervention group showed a 39% lower risk for MetS incidence (HR = 0.61, 95% CI = 0.44–0.85) compared to controls, during the first 6 years after baseline assessment (short term), although the risk lowering effect of the intervention was not maintained long term.

Conclusion

A healthy lifestyle education was successful in reducing the short-term risk of MetS in children. To identify ways of maintaining long-term results, further research is definitely warranted.

Trial Registration

This study was funded by National Research Council and Planning and Management Organization and has been reviewed and approved by the Iranian registry of clinical trials (ISRCTN52588395).
  相似文献   
58.
AIM: To improve our understanding of Iranian regional variation in Helicobacter pylori (H. pylori ) antibiotic resistance rates to find the best antibiotic therapy for eradication of H. pylori infections.METHODS: A total of 266 patients undergoing endoscopy in Shiraz, Southern Iran, were included in this study. H. pylori strains were isolated from antral biopsies by culture and confirmed by the rapid urease-test and gram staining. Antibiotic susceptibility of H. pylori isolates was determined by E-test.RESULTS: A total of 121 H. pylori strains were isolated, 50 from male and 71 from female patients. Data showed that 44% (n = 53), 20% (n = 24), 5% (n = 6), and 3% (n = 4) of all strains were resistant to the antibiotics metronidazole, amoxicillin, clarithromycin, and tetracycline, respectively. When the antibiotics were considered together we found 11 sensitivity patterns for the strains. Resistance to metronidazole was significantly higher in female than in male patients (P < 0.05). In about 71% of the metronidazole-resistant isolates, the minimum inhibitory concentrations (MICs) exceeded 256 μg/mL.CONCLUSION: We found a moderate rate of primary resistance to metronidazole. However, a high MIC (> 256 mg/L) which was found in 71% of the isolates is considerable. In the case of amoxicillin, an increased resistance rate of 20% is worrying. Resistance to clarithromycin and tetracycline is also emerging among the H. pylori strains in our region.  相似文献   
59.

Background and the purpose of the study

Natural products from plants have an important role in the development and production of new drugs mainly for cancer therapy. More recently, we have shown that the pericarp methanolic extract of Pistacia atlantica sub kurdica (with local name of Baneh) as a rich source of active biological components with high antioxidant and radical scavenging activities, has ability to cease proliferation and induce apoptosis in T47D human breast cancer cells. The present study aimed to clarify whether Baneh extract able to alter cell cycle progression of T47D cells or not.

Methods

In order to study the possible effect of Baneh extract on cell cycle of T47D cells, we evaluated cell cycle distribution and its regulatory proteins by flow cytometry and western blot analysis respectively.

Results

Baneh extract induced G0/G1 cell cycle arrest in conjunction with a marked decrease in expression of cyclin D1 and cdk4 that was strongly dependent on time of exposure. In parallel, Dox-treated T47D cells in early time points were accumulated on S phase, but after 48 h cell cycle progression was inhibited on G2/M. Dox promoted striking accumulation of cyclin B1 rapidly and enhanced cyclin A abundance.

Conclusion

Taken together, our results establish that the antitumor activity of the pericarp extract of Baneh partly is mediated via cell cycle arrest and downregulation of cyclin D1 and cdk4 expression. These findings warrant further evaluation regarding the mechanism(s) of action of this promising anticancer agent.  相似文献   
60.
Plants as important source of natural active components with anticancer effects commonly are different in structure and biological properties. The pericarp of Pistacia atlantica sub kurdica with local name of Baneh, a rich source of active phytochemicals, contains noticeable amounts of polyphenolic compounds, flavonoids and anthocyanins. Therefore, the antiproliferative, apoptosis induction and cell cycle alterations of Baneh were evaluated in human colon carcinoma HT29 cells. The Baneh extract (0.7 mg/ml) resulted in 50% growth inhibition similar to 500 nM of Doxorubicin (Dox) in HT29 cells after 72 h. The down-regulation of cyclin A protein by Baneh extract induced S phase delay in cell cycle progression of HT29 cells. Unlike the Baneh extract, Dox showed G2/M accumulation of HT29 cells which was associated with an increase in cyclin A and cyclin B1 protein expression. Furthermore, the induction of apoptosis following Baneh extract and Dox treatment in HT29 cells was confirmed by DNA fragmentation and translocation of phosphatidylserine. The morphological characteristics of apoptosis were also observed in HT29 cells exposed to the Baneh extract and Dox. These results suggest that due to the existence of bioactive components, methanolic extract of the Baneh has significant cytotoxic effects against human colon carcinoma HT29 cells.  相似文献   
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