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The epidemiology of HIV infection in the US in general, and in the southeast, in particular, has shifted dramatically over the past two decades, increasingly affecting women and minorities. The site for our intervention was an infectious diseases clinic based at a university hospital serving over 1,300 HIV-infected patients in North Carolina. Our patient population is diverse and reflects the trends seen more broadly in the epidemic in the southeast and in North Carolina. Practicing safer sex is a complex behavior with multiple determinants that vary by individual and social context. A comprehensive intervention that is client-centered and can be tailored to each individual’s circumstances is more likely to be effective at reducing risky behaviors among clients such as ours than are more confrontational or standardized prevention messages. One potential approach to improving safer sex practices among people living with HIV/AIDS (PLWHA) is Motivational Interviewing (MI), a non-judgmental, client-centered but directive counseling style. Below, we describe: (1) the development of the Start Talking About Risks (STAR) MI-based safer sex counseling program for PLWHA at our clinic site; (2) the intervention itself; and (3) lessons learned from implementing the intervention.  相似文献   
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Osteogenesis is synergistically enhanced by the combined effect of complimentary factors. This study showed that Nell-1 and BMP-2 synergistically enhanced osteogenic differentiation of myoblasts and phosphorylated the JNK MAPK pathway. The findings are important because of the osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of coordinated BMP-2 and Nell-1 delivery. INTRODUCTION: BMPs play an important role in the migration and proliferation of mesenchymal cells and have a unique ability to alter the differentiation of mesenchymal cells toward chondrogenic and osteogenic lineages. Signaling upstream of Cbfa1/Runx2, BMPs effects are not limited to cells of the osteoblast lineage. Thus, additional osteoblast-specific factors that could synergize with BMP-2 would be advantageous for bone regeneration procedures. NELL-1 (NEL-like molecule-1; NEL [a protein strongly expressed in neural tissue encoding epidermal growth factor like domain]) is a novel growth factor believed to preferentially target cells committed to the osteochondral lineage. MATERIALS AND METHODS: C2C12 myoblasts were transduced with AdLacZ, AdNell-1, AdBMP-2, or AdNell-1+AdBMP-2 overexpression viruses. Effects were studied by cell morphology, alkaline phosphatase activity, osteopontin production, and MAPK signaling. Additionally, in a nude mouse model, viruses were injected into leg muscles, and new bone formation was examined after 2 and 8 wk. RESULTS: C2C12 myoblasts co-transduced with AdNell-1+AdBMP-2 showed a synergistic effect on osteogenic differentiation as detected by alkaline phosphatase activity and osteopontin production. Nell-1 stimulation on AdNell-1 + AdBMP-2 preconditioned C2C12 cells revealed significant activation of the non-BMP-2 associated c-Jun N-terminal kinase (JNK) MAPK signaling pathway, but not the p38 or extracellular signal-regulated kinase (ERK1/2) MAPK pathways. Importantly Nell-1 alone did not induce osteogenic differentiation of myoblasts. In a nude mouse model, injection of AdNell-1 alone stimulated no bone formation within muscle; however, injection of AdNell-1+AdBMP-2 stimulated a synergistic increase in bone formation compared with AdBMP-2 alone. CONCLUSIONS: These findings are important because of the confirmed osteochondral specificity of Nell-1 signaling and the potential therapeutic effects of enhanced BMP-2 action with coordinated Nell-1 delivery.  相似文献   
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To identify risk factors for fractures in multi-ethnic women, we studied 159,579 women enrolled in the Women's Health Initiative. In general, risk factors for fractures were similar across ethnic groups. However, irrespective of their ethnicity, women with multiple risk factors have a high risk of fracture. Targeting these high-risk women for screening and intervention could reduce fractures. INTRODUCTION: Fracture rates tend to be lower in minority women, but consequences may be greater. In addition, the number of fractures is expected to increase in minority women because of current demographic trends. There are limited prospective data on risk factors for fractures in minority women. MATERIALS AND METHODS: We studied 159,579 women 50-79 yr of age enrolled in the Women's Health Initiative. Information on risk factors was obtained by questionnaire or examination. Nonspine fractures that occurred after study entry were identified over an average follow-up of 8 +/- 2.6 (SD) yr. RESULTS: Annualized rates (%) of fracture in whites, blacks, Hispanics, Asians, and American Indians were 2.0, 0.9, 1.3, 1.2, and 2.0, respectively. Significant predictors [HR (95% CI)] of fractures by ethnic group were as follows: blacks: at least a high school education, 1.22 (1.0, 1.5); (+) fracture history, 1.7 (1.4, 2.2); and more than two falls, 1.7 (1.9, 2.0); Hispanics: height (>162 cm), 1.6 (1.1, 2.2); (+) fracture history, 1.9 (1.4, 2.5); more than two falls, 1.8 (1.4, 2.3); arthritis, 1.3 (1.1, 1.6); corticosteroid use, 3.9 (1.9, 8.0); and parental history of fracture, 1.3 (1.0, 1.6); Asians: age (per 5 yr), 1.2 (1.0, 1.3); (+) fracture history, 1.5 (1.1, 2.0); current hormone therapy (HT), 0.7 (0.5, 0.8); parity (at least five), 1.8 (1.1, 3.0); more than two falls, 1.4 (1.1, 1.9); American Indian: (+) fracture history, 2. 9 (1.5, 5.7); current HT, 0.5 (0.3, 0.9). Women with eight or more risk factors had more than a 2-fold higher rate of fracture compared with women with four or fewer risk factors. Two ethnicity x risk factor interactions were identified: age and fall history. CONCLUSIONS: Irrespective of their ethnicity, women with multiple risk factors have a high risk of fracture. Targeting these high-risk women for screening and intervention could reduce fractures.  相似文献   
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Aim: This article reviews research centred around juvenile bipolar disorder with particular reference to diagnostic difficulties. Putative deficits are scrutinized with respect to trait likelihood and the roles of neuropsychology and neuroimaging in enhancing our understanding of juvenile bipolar disorder are discussed. Methods: Search terms including childhood, adolescent, youth and juvenile combined with the terms ‘bipolar disorder’, mania, depression and hypomania were used to identify relevant studies in MEDLINE and PsychLit. Results: Over recent years research into this relatively new disorder has increased phenomenally. Key issues within the field include diagnostic specificity, the heritability of the disorder, the impact of comorbidity and the implications of neuropsychological and neuroimaging findings. Conclusion: Despite concerning controversies in literature the diagnosis of bipolar disorder in children and adolescents as compared with adults, promising future research directions include better neurological characterization of the disorder through the application of findings from clinical populations, neuropsychological and neuroimaging research.  相似文献   
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The role of the Rho-Rho kinase signaling pathway on osteoblast differentiation was investigated using primary mouse calvarial cells. The bacterial toxin PMT inhibited, whereas Rho-ROK inhibitors stimulated, osteoblast differentiation and bone nodule formation. These effects correlated with altered BMP-2 and -4 expression. These data show the importance of Rho-ROK signaling in osteoblast differentiation and bone formation. INTRODUCTION: The signal transduction pathways controlling osteoblast differentiation are not well understood. In this study, we used Pasteurella multocida toxin (PMT), a unique bacterial toxin that activates the small GTPase Rho, and specific Rho inhibitors to investigate the role of Rho in osteoblast differentiation and bone formation in vitro. MATERIALS AND METHODS: Primary mouse calvarial osteoblast cultures were used to investigate the effects of recombinant PMT and Rho-Rho kinase (ROK) inhibitors on osteoblast differentiation and bone nodule formation. Osteoblast gene expression was analyzed using Northern blot and RT-PCR, and actin rearrangements were visualized after phalloidin staining and confocal microscopy. RESULTS: PMT stimulated the proliferation of primary mouse calvarial cells and markedly inhibited the differentiation of osteoblast precursors to bone nodules with a concomitant inhibition of osteoblastic marker gene expression. There was no apparent causal relationship between the stimulation of proliferation and inhibition of differentiation. PMT caused cytoskeletal rearrangements because of activation of Rho, and the inhibition of bone nodules was completely reversed by the Rho inhibitor C3 transferase and partly reversed by inhibitors of the Rho effector, ROK. Interestingly, Rho and ROK inhibitors alone potently stimulated osteoblast differentiation, gene expression, and bone nodule formation. Finally, PMT inhibited, whereas ROK inhibitors stimulated, bone morphogenetic protein (BMP)-2 and -4 mRNA expression, providing a possible mechanism for their effects on bone nodule formation. CONCLUSIONS: These results show that PMT inhibits osteoblast differentiation through a mechanism involving the Rho-ROK pathway and that this pathway is an important negative regulator of osteoblast differentiation. Conversely, ROK inhibitors stimulate osteoblast differentiation and may be potentially useful as anabolic agents for bone.  相似文献   
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Proteases that reduce insulin-like growth factor binding protein-3 affinity for insulin-like growth factor-I have been found in various biological fluids from human beings and rats. The aim of this study was to assess the local and systemic role of insulin-like growth factor binding protein-3 proteases in the course of wound healing. Six rats had polyvinyl alcohol sponges implanted subcutaneously. Wound fluid and serum were collected 3 days after wounding. Gel filtration experiments showed that insulin-like growth factor-I was present as a 150 kDa complex in both serum and wound fluid. However, insulin-like growth factor binding protein-3 measured by Western ligand blotting was virtually absent in wound fluid. Co-incubation of serum and wound fluid resulted in an ethylenediamine tetraacetic acid-inhibitable degradation of serum insulin-like growth factor binding protein-3, suggesting the presence of an insulin-like growth factor binding protein-3 degrading activity in wound fluid. Incubation of ((125)I)-labeled insulin-like growth factor binding protein-3 in wound fluid and serum showed a rapid and time-dependent proteolysis of insulin-like growth factor binding protein-3 in wound fluid with metabolites similar to those generated by human term pregnant serum. No sign of insulin-like growth factor binding protein-3 degrading activity was observed in rat-serum. In conclusion, there is an insulin-like growth factor binding protein-3 proteolytic activity in wound fluid, and it is hypothesized that this activity results in a localized increase in insulin-like growth factor-I bioactivity.  相似文献   
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One hundred forty five individuals who sought medical attention as a result of a motor vehicle accident (MVA), and who were initially assessed 1 to 4 months post-MVA, were followed up prospectively for 6 months to determine how many of the 55 with posttraumatic stress disorder (PTSD) and the 43 with sub-syndromal PTSD would remit and what variables would predict remission. Thirty (55%) of those with initial PTSD had remitted at least in part by 6 months while 67% of those with sub-syndromal PTSD had remitted (and 5% had worsened). Four variables, including severity of initial symptoms, degree of initial physical injury, relative degree of physical recovery by 4 months and whether a close family member suffered a trauma during the follow-up interval, combined to classify 6-month clinical status of 84% of those with initial PTSD secondary to MVAs.  相似文献   
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