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Tatiana Z. Brinckerhoff Sandhya Bondada Catherine E. Lewis Samuel W. French Daniel A. DeUgarte 《Surgery for obesity and related diseases》2013,9(1):108-112
BackgroundAlthough women disproportionately undergo bariatric surgery, the rodent models investigating the mechanisms of bariatric surgery have been limited to males. Female rodent models can also potentially allow us to understand the effects of surgical intervention on future generations of offspring. Sleeve gastrectomy is an attractive weight loss procedure for reproductive-age female patients because it avoids the malabsorption associated with intestinal bypass. We sought to evaluate the effect of sleeve gastrectomy on young female rats with diet-induced obesity at the University of California, Los Angeles, David Geffen School of Medicine.MethodsSprague-Dawley female rats were fed a 60% high-fat diet. At 12 weeks of age, the rats underwent either sleeve gastrectomy or sham surgery. The rats were killed 4 weeks after surgery. A chemistry panel was performed, and the serum adipokines and gut hormones were assayed. The homeostasis model assessment score was calculated. The liver histologic findings were graded for steatosis. The 2-sample t test was used to compare the results between the 2 groups.ResultsSleeve gastrectomy was associated with significant weight loss (5% ± 6% versus ?4% ± 6%; P < .001), lower leptin levels (1.3 ± 1.2 versus 3.5 ± 2.3 ng/mL; P < .01), and higher adiponectin levels (.43 ± .19 versus .17 ± .14 ng/mL; P < .004) compared with the sham-operated rats. No significant differences were found in the fasting ghrelin levels. Furthermore, we did not observe evidence of insulin resistance or steatohepatitis after 11 weeks of high-fat diet. Despite these limitations, additional gender-specific studies are warranted given that most bariatric surgeries are performed in women.ConclusionSleeve gastrectomy appears to result in weight loss and improvements in adiponectin and leptin by way of mechanisms independent of ghrelin levels in a female model of diet-induced obesity. 相似文献
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Alexis Donneys Daniela M. Weiss Sagar S. Deshpande Salman Ahsan Catherine N. Tchanque-Fossuo Deniz Sarhaddi Benjamin Levi Steven A. Goldstein Steven R. Buchman 《BONE》2013,52(1):318-325
BackgroundMedically based efforts and alternative treatment strategies to prevent or remediate the corrosive effects of radiotherapy on pathologic fracture healing have failed to produce clear and convincing evidence of success. Establishing an effective pharmacologic option to prevent or treat the development of non-unions in this setting could have immense therapeutic potential. Experimental studies have shown that deferoxamine (DFO), an iron-chelating agent, bolsters vascularity and subsequently enhances normal fracture healing when injected locally into a fracture callus in long bone animal models. Since radiotherapy is known to impede angiogenesis, we hypothesized that the pharmacologic addition of DFO would serve to mitigate the effects of radiotherapy on new vessel formation in vitro and in vivo.Materials and MethodsIn vitro investigation of angiogenesis was conducted utilizing HUVEC cells in Matrigel. Endothelial tubule formation assays were divided into four groups: Control, Radiated, Radiated + Low-Dose DFO and Radiated + High-Dose DFO. Tubule formation was quantified microscopically and video recorded for the four groups simultaneously during the experiment. In vivo, three groups of Sprague–Dawley rats underwent external fixator placement and fracture osteotomy of the left mandible. Two groups received pre-operative fractionated radiotherapy, and one of these groups was treated with DFO after fracture repair. After 40 days, the animals were perfused and imaged with micro-CT to calculate vascular radiomorphometrics.ResultsIn vitro, endothelial tubule formation assays demonstrated that DFO mitigated the deleterious effects of radiation on angiogenesis. Further, high-dose DFO cultures appeared to organize within 2 h of incubation and achieved a robust network that was visibly superior to all other experimental groups in an accelerated fashion. In vivo, animals subjected to a human equivalent dose of radiotherapy (HEDR) and left mandibular fracture demonstrated quantifiably diminished μCT metrics of vascular density, as well as a 75% incidence of associated non-unions. The addition of DFO in this setting markedly improved vascularity as demonstrated with 3D angiographic modeling. In addition, we observed an increased incidence of bony unions in the DFO treated group when compared to radiated fractures without treatment (67% vs. 25% respectively).ConclusionOur data suggest that selectively targeting angiogenesis with localized DFO injections is sufficient to remediate the associated severe vascular diminution resulting from a HEDR. Perhaps the most consequential and clinically relevant finding was the ability to reduce the incidence of non-unions in a model where fracture healing was not routinely observed. 相似文献
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Present cross-sectional study examined perceptions of recovery-oriented services and reports of professional burnout and job satisfaction in a sample of 114 case managers working in community mental health centers across Ohio. The research examined the relative contribution of demographic characteristics, the structure of case management services, and case managers’ beliefs about recovery-oriented services in describing their reports of professional burnout and job satisfaction. Regardless of individual characteristics of case managers and reports of the structure of their jobs, case managers who perceived their agency to offer higher levels of recovery-oriented services also reported lower levels of depersonalization and emotional exhaustion at work, and higher levels of professional accomplishment and job satisfaction. Directions for future research in the area are discussed. 相似文献
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Adeline Nyamathi Barbara Kennedy Catherine Branson Benissa Salem Farinaz Khalilifard Mary Marfisee Daniel Getzoff Barbara Leake 《Community mental health journal》2013,49(2):178-184
In a prospective two-group pilot study of a convenient sample of 156 young adults, we assessed improvement in HIV cognitive and transmission knowledge, hepatitis knowledge, and mental health at six-month follow-up. Multiple linear regression analysis revealed higher six-month scores in total HIV/AIDS knowledge, HIV/AIDS cognitive knowledge, HIV transmission knowledge and HBV and HCV knowledge at 6 months in the Hepatitis Health Promotion (HHP) group compared to the Art Messaging (AM) group. Moreover, homeless young participants who reported having significant others in their lives, and excellent or very good health did better than their counterparts. Youth who were attempting to get their lives together had higher scores for all types of knowledge except HBV. Hallucinogen users had significantly worse scores on all knowledge measures than non-users. Lastly, the HHP group revealed an improvement in psychological well-being compared to the AM group. 相似文献
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Cecilia A. Essau Beatriz Olaya Gholamreza Pasha Catherine Gilvarry Diane Bray 《Child psychiatry and human development》2013,44(1):123-136
This study investigated the psychometric properties of the Iranian translation of the Centre for Epidemiological Studies Depression Scale for Children (CES-DC) in school children and adolescents in Iran. The CES-DC is a 20-item self-report scale designed to measure depressive symptoms in children and adolescents. A total of 1,984 children and adolescents, aged 12–17 years, participated in this research. In addition to the CES-DC, all participants completed the Spence Children’s Anxiety Scale (SCAS) and the Strength and Difficulties Questionnaire (SDQ). The CES-DC demonstrated high internal consistency (Cronbach Alpha = .87). Confirmatory factor analyses revealed the same four factor structure as proposed by Radloff. Invariance tests showed an equivalent structure among boys and girls and younger and older adolescents. The CES-DC total scores correlated significantly with the SCAS total scores and the SDQ emotional symptoms subscale, providing support of its convergent validity. To conclude, the CES-DC proved to be a reliable and valid measure of depressive symptoms in the Iranian context. 相似文献