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71.
Hypofunction of the serotonergic system is often associated with major depression and obsessive compulsive disorder (OCD). Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed to treat these disorders, and require 3–6 weeks of chronic treatment before improvements in the symptoms are observed. SSRIs inhibit serotonin''s transporter, and in doing so, increase extracellular serotonin concentrations. Thus, efficacy of SSRIs likely depends upon the brain''s adaptive response to sustained increases in serotonin levels. Individual responsiveness to SSRI treatment may depend on a variety of factors that influence these changes, including ongoing stress. Social isolation is a passive, naturalistic form of chronic mild stress that can model depression in rodents. In this study, we examined how 20-day treatment with the SSRI citalopram (CIT) alters marble-burying (MB), open field behavior, and serotonin signaling in single- vs pair-housed animals. We used in vivo voltammetry to measure electrically evoked serotonin, comparing release rate, net overflow, and clearance. Pair-housed mice were significantly more responsive to CIT treatment, exhibiting reduced MB and facilitation of serotonin release that positively correlated with the frequency of electrical stimulation. These effects of CIT treatment were attenuated in single-housed mice. Notably, although CIT treatment enhanced serotonin release in pair-housed mice, it did not significantly alter uptake rate. In summary, we report that chronic SSRI treatment facilitates serotonin release in a frequency-dependent manner, and this effect is blocked by social isolation. These findings suggest that the efficacy of SSRIs in treating depression and OCD may depend on ongoing stressors during treatment.  相似文献   
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We performed a retrospective analysis of germline DNA samples from Ashkenazi Jewish men and a comparison group of non-Ashkenazi men treated for prostate cancer at our institution to determine the prevalence of HOXB13 G84E mutation in prostate cancer patients of Ashkenazi Jewish heritage, an ethnic group common to the New York City area. Patients were genotyped for G84E using a TaqMan assay (Applied Biosystems). Positive cases were confirmed using Sanger sequencing. Median age at prostate cancer diagnosis was 68 years for 889 Ashkenazi Jewish patients, 64 years for 920 non-Ashkenazi Jewish patients. The median follow up was 9 years for Ashkenazi Jewish patients and 8.8 years for non-Ashkenazi Jewish patients. Only 4 patients were found to be heterozygous carriers of G84E. They were all of non-Ashkenazi Jewish ancestry and were diagnosed at 70, 66, 78, and 49 years of age. Two of them presented with high-risk prostate cancer. The prevalence of G84E in the non-Ashkenazi sample was 0.4 %. HOXB13 G84E mutation was not observed in prostate cancer patients of Ashkenazi Jewish ancestry treated at our institution. Screening for G84E, therefore, may be unnecessary in Ashkenazi Jewish men if these results are validated by other studies.  相似文献   
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An endless number of career trajectories are possible for gerontologists. With a growing aging population, our skills and areas of expertise are of high value to numerous industries. The purpose of this study is to describe the professional development and career trajectories of alumni of U.S. doctoral gerontology programs obtained through the Gerontology Education Longitudinal Study (GELS). Specifically, the authors examine how professional identification, doctoral program career preparation, and perception of job prospects affect alumni decisions to pursue “traditional” (i.e., academic) versus “nontraditional” (i.e., non-academic) careers. Results from the GELS revealed a fairly even split in the alumni sample of careers in traditional and nontraditional settings. The decision to pursue a traditional versus nontraditional career was not significantly associated with personal identification, doctoral program career preparation, or perception of employment options. These results suggest that the skill set obtained in doctoral gerontology programs is useful and is in demand in a variety of careers; therefore, doctoral programs may want to consider tailoring training to meet students’ future career goals in both academic and non-academic settings.  相似文献   
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Coagulation disorders account for a high incidence of death in the U.S. due to stroke, myocardial infarction, and venous thromboembolism. In the past few years, numerous agents have been brought to market for the treatment of thromboembolism or prevention of thromboembolism. Similar to warfarin, these agents can cause bleeding disorders, which may exacerbate dental care treatment plans. This literature review examines the newer agents for the treatment of thromboembolism disorders, common side effects and drug interactions, the specific medical conditions each agent treats, and the dental perspective on how to medically management patients prescribed these medications.  相似文献   
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BACKGROUND: Light-induced fluorescence endoscopy (LIFE) may improve the detection of high-grade dysplasia (HGD) and early stage cancer (EC) in Barrett's esophagus (BE). The aim of this study was to compare LIFE with standard endoscopy (SE) in a randomized crossover study. METHODS: Fifty patients with BE underwent SE and LIFE in a randomized sequence (4 to 6-week interval between procedures). The two procedures were performed by two different endoscopists who were blinded to the findings of the other examination. Targeted biopsy specimens were taken from detected lesions, followed by random biopsy specimens with a 2-cm interval, 4-quadrant protocol. Biopsy specimens were routinely evaluated and subsequently reviewed by a single, blinded expert GI pathologist. RESULTS: Targeted biopsy specimens had a sensitivity for the diagnosis of HGD/EC of 62% (8/13) for both techniques. The overall sensitivity (all biopsy specimens) was 85% for SE and 69% for LIFE (p = 0.69). All targeted biopsy specimens had a positive predictive value (PPV) for HGD/EC of 41% for SE and 28% for LIFE (p = 0.40); autofluorescence-targeted biopsy specimens had a PPV of 13%. False-positive lesions had a significantly higher rate of acute inflammation than random biopsy specimens. CONCLUSIONS: In this study, LIFE did not improve the detection of HGD or EC in patients with BE compared with SE.  相似文献   
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BACKGROUND/AIMS: The aim of the study is to clarify the effects of octreotide and propranolol, agents used in the treatment of portal hypertension, on mucosal changes in portal hypertensive colopathy. METHODOLOGY: Portal hypertension was induced in all rats by partial portal vein ligation, and after the operation all rats were caged for a 10-week period. Then, animals were divided into three groups and for two weeks medical treatment were administered to the individual groups as follows: Control group, saline 0.5 mL/day, intraperitoneally. Octreotide group, octreotide 100 micrograms/kg/12 hours, subcutaneously. Propranolol group, propranolol 20 mg/kg/day, intraperitoneally. In order to assess the portal hypertensive colopathy, criteria such as mean diameters of dilated vessels in colonic mucosa, and the existence of mucosal edema, capillary ectasia, hyperemia and hemorrhage, inflammation were used. RESULTS: When parameters were compared for the control versus propranolol groups, mucosal edema and hyperemia and hemorrhage criteria were found to be significant for the propranolol group; control versus octreotide groups, mucosal edema, capillary ectasia, and hyperemia and hemorrhage criteria were found to be significant for the octreotide group; octreotide versus propranolol groups, capillary ectasia and mucosal edema criteria were found to be significant for the octreotide group. CONCLUSIONS: The mucosal changes in portal hypertensive colopathy could be corrected by drugs modifying portal blood flow, octreotide may find a place in the treatment of portal hypertensive colopathy.  相似文献   
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