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991.
The histiocytoses are rare diseases caused by alterations in the monocyte-histiocytic series with several clinical findings. Among the cutaneous syndromes of non-Langerhans cells, xanthoma disseminatum is the only disease of this group that has been classically associated to the central diabetes insipidus (CDI). The case reported describes a 30-year-old man that two years after presenting with CDI developed non confluent disseminated cutaneous brown papular lesions throughout the body. The histopathology, immunohistochemistry, and electronic microscopy were compatible with the diagnosis of non-Langerhans histiocytoses, suggesting the diagnosis of juvenile xanthogranuloma. The endocrine-metabolic evaluation did not show other alterations besides CDI in a 10-year follow up. The magnetic resonance of hypophysis showed absence of the pituitary hyperintense sign (bright spot). The radiologic and scinthigraphic evaluation of the bones did not show the presence of osteolytic lesions. This case prints out the importance of skin examination in cases of CDI and its association with cutaneous non-Langerhans histiocytoses in a broader spectrum, rather then restricted to the cases of xanthoma disseminatum.  相似文献   
992.
Tumoral hyperprolactinemia and consequent hypogonadism have been associated with osteoporosis. Bone mineral density (BMD) was measured by dual-energy RX absorptiometry in 24 patients with prolactinoma (15 macro and 9 micro adenomas; age range = 18 to 49 years). Student unpaired t or Mann-Whitney tests were used to compare groups, and Spearman test studied correlations. Lumbar spine (LS) was the most affected, as LS Z-score was < -2 SD in 20.83% of the patients. No difference was found in densitometric parameters for the comparison between macro and microprolactinoma, or those with normal prolactin versus hyperprolactinemia. LS BMD and LS Z-score were higher in the patients with > 8 menstrual cycles in the preceding year then in those with oligoamenorrhea (p = 0.030). The number of cycles was correlated to LS BMD (r = 0.515, p = 0.017) and body mass index to femoral neck BMD (r = 0.563, p = 0.006) and total femur BMD (r = 0.529, p = 0.011). CONCLUSIONS: Decreased bone mineral density was detected in 20.83% of our young patients with prolactinoma. The great involvement of trabecular bone skeletal regions, such as vertebrae, suggests the participation of hypogonadism in the pathogenesis of bone disease. Irrespective of prolactin levels, return to normal menses seems the best index of good control.  相似文献   
993.
Liver gene transfer is a highly sought goal for the treatment of inherited and infectious diseases. Lentiviral vectors (LVs) have many desirable properties for hepatocyte-directed gene delivery, including the ability to integrate into nondividing cells. Unfortunately, upon systemic administration, LV transduces hepatocytes relatively inefficiently compared with nonparenchymal cells, and the duration of transgene expression is often limited by immune responses. Here, we investigated the role of innate antiviral responses in these events. We show that administration of LVs to mice triggers a rapid and transient IFNalphabeta response. This effect was dependent on functional vector particles, and in vitro challenge of antigen-presenting cells suggested that plasmacytoid dendritic cells initiated the response. Remarkably, when LVs were administered to animals that lack the capacity to respond to IFNalphabeta, there was a dramatic increase in hepatocyte transduction, and stable transgene expression was achieved. These findings indicate that, even in the setting of acute delivery of replication-defective vectors, IFNs effectively interfere with transduction in a cell-type-specific manner. Moreover, because disabling a single component of the innate/immune network was sufficient to establish persistent xenoantigen expression, our results raise the hope that the immunologic barriers to gene therapy are less insurmountable than expected.  相似文献   
994.
Systemic delivery of lentiviral vector (LV) in immunocompetent mice leads to efficient in vivo cell transduction and expression of the encoded protein under the control of the ubiquitous promoter of human cytomegalovirus (CMV). However, antitransgene immune response results in clearance of transduced cells 4 weeks after injection. T regulatory cells (Tregs), which have been demonstrated to control immune responses in vivo, were tested for their ability to suppress antitransgene response leading to stable long-term expression. Adoptive transfer of natural CD4(+)CD25(+) Tregs (nTregs) isolated from wild type (wt) mice or from transgene tolerant transgenic (tg) mice did not suppress the antitransgene immune response after LV delivery. These data demonstrate that neither increasing the endogenous pool of natural Tregs nor transferring nTregs selected in a transgene-expressing thymus can modulate the immune response and mediate sustained transgene expression. Conversely, adoptive transfer of antigen-presenting cells (APCs) isolated from transgene-tolerant tg mice efficiently reduced the immune response leading to stable LV-encoded protein expression in vivo. Reduction of CD8(+) effector T cells was observed in LV-treated mice coinjected with transgene-expressing APCs compared with control mice. These data indicate that antitransgene immune response can be modulated by transgene-expressing APCs possibly through deletion of effector T cells.  相似文献   
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The purpose of this study was to evaluate the efficacy of two brief interventions and the inclusion of a 1-month booster session with college students who were referred to attend alcohol education following an alcohol-related incident. Participants (N=225; 48.9% male) were randomly assigned to receive one session of a Brief Motivational Interview (BMI) or computer-delivered intervention (CDI) with the Alcohol 101 CD-ROM. Participants were also randomly assigned to booster/no booster. At 3-month follow up, participants in BMI reported greater help seeking and use of behavioral strategies to moderate drinking. At 12-month follow up, BMI participants were drinking more frequently and CDI participants were consuming a greater number of drinks per occasion than at baseline. Mediation analyses showed that the use of specific behavioral strategies mediated the effect of the BMI condition on drinking volume. There was no intervention effect on alcohol problems, and the booster condition did not significantly affect outcomes. Promoting specific behaviors in the context of in-person brief interventions may be a promising approach to reducing drinking volume among identified at-risk students.  相似文献   
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