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The distal region on the short arm of chromosome 9 is of special interest for scientists interested in sex development as well as in the clinical phenotype of patients with the 9p deletion syndrome, characterized by mental retardation, trigonocephaly and other dysmorphic features. Specific genes responsible for different aspects of the phenotype have not been identified. Distal 9p deletions have also been reported in patients with 46,XY sex reversal, with or without 9p deletion syndrome. Within this region the strongest candidates for the gonadal dysgenesis phenotype are the DMRT genes; however, the genetic mechanism is not clear yet. Multiple ligation-dependent probe amplification represents a useful technique to evaluate submicroscopic interstitial or distal deletions that would help the definition of the minimal sex reversal region on 9p and could lead to the identification of gene(s) responsible of the 46,XY gonadal disorders of sex development (DSD). We designed a synthetic probe set that targets genes within the 9p23-9p24.3 region and analyzed a group of XY patients with impaired gonadal development. We characterized a deletion distal to the DMRT genes in a patient with isolated 46,XY gonadal DSD and narrowed down the breakpoint in a patient with a 46,XY del(9)(p23) karyotype with gonadal DSD and mild symptoms of 9p deletion syndrome. The results are compared with other patients described in the literature, and new aspects of sex reversal and the 9p deletion syndrome candidate regions are discussed.  相似文献   
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Lymphocytosis associated with viral infection is generally polyclonal or oligoclonal. In this article, we describe a case of transient monoclonal CD8+/CD57+ T-cell lymphocytosis with large granular lymphocyte (LGL) morphology occurring after primary CMV infection and review cases of virus-associated monoclonal CD8+ T-cell expansions reported in the literature. Several clinical features shared by virus-associated monoclonal CD8+ T-cell expansions suggest the reactive nature of the lymphocytosis. Based on this, our case report and those reported in the literature support the notion that T-cell receptor clonality per se is not necessarily indicative of malignancy. These observations further corroborate the need for a close follow-up before assigning the diagnosis of LGL leukemia to individuals developing monoclonal CD8+ T-cell expansions.  相似文献   
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The critical tissues that require regeneration in the periodontium are of mesenchymal origin; therefore, the ability to identify, characterize and manipulate mesenchymal stem cells within the periodontium is of considerable clinical significance. In particular, recent findings suggest that periodontal ligament cells may possess many osteoblast-like properties. In the present study, periodontal ligament mesenchymal stem cells obtained from healthy volunteers were maintained in culture until confluence and then induced to osteogenic differentiation. Intracellular calcium ([Ca2+]i) concentration and nitric oxide, important signalling molecules in the bone, were measured along with cell differentiation. Alkaline phosphatase activity was assayed and bone nodule-like structures were evaluated by means of morphological and histochemical analysis. Our results showed that the periodontal ligament mesenchymal stem cells underwent an in vitro osteogenic differentiation, resulting in the appearance of active osteoblast-like cells together with the formation of calcified deposits. Differentiating cells were also characterized by an increase of [Ca2+]i and nitric oxide production. In conclusion, our data show a link between nitric oxide and the osteogenic differentiation of human periodontal ligament mesenchymal stem cells, thus suggesting that local reimplantation of expanded cells in conjugation with a nitric oxide donor could represent a promising method for treatment of periodontal defects.  相似文献   
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ObjectiveWe tested in mice the hypothesis that ingestion of infusions of green tea, white tea, or the aromatic plant Pelargonium purpureum increases total antioxidant capacity (TAC) of plasma and organs.MethodsTwenty-five mice were randomly assigned to five groups, each of which received by gavage 0.1 mL of infusion from green tea, white tea, or P. purpureum (8 g/100 mL of water) or catechin (0.01 g/100 mL) or water for 5 consecutive days. On the fifth day the animals were euthanized. Blood was taken by heart puncture and the heart, lungs, liver, spleen, kidney, and brain were removed. TAC was measured in plasma and in all organ homogenates with the ferric reducing antioxidant power assay and in selected organ homogenates by the total radical-trapping antioxidant parameter assay.ResultsGreen tea and P. purpureum increased TAC in the plasma and lungs, whereas green tea, white tea, and catechin increased TAC in heart homogenates. No effect was observed on the liver, brain, spleen, and kidney homogenates in comparison with the water control with the ferric reducing antioxidant power assay or the total radical-trapping antioxidant parameter assay.ConclusionThese results suggest that green tea, white tea, and P. purpureum exhibit antioxidant effects in vivo that may be observed not only in plasma but also in some organs.  相似文献   
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Vascular Endothelial Growth Factor (VEGF)-D is a member of the VEGF family of angiogenic growth factors that activate the Vascular Endothelial Growth Factor Receptor (VEGFR)-2 and VEGFR-3, which are mainly expressed in blood and lymphatic vessels. Here we have analyzed by using monoclonal antibodies, the expression of VEGF-D and its cognate receptor VEGFR-3 in normal and pathologic bone marrow and lymph node biopsies. This analysis revealed that VEGF-D is expressed in B cells of the germinal centers, scattered B and T blasts, myeloid progenitors, acute leukemia, several types of non Hodgkin lymphoma, and classical Hodgkin's lymphoma. In normal tissues VEGFR-3 was only expressed in fenestrated capillaries of bone marrow and in lymphatic vessels of lymph nodes, while in VEGF-D expressing tumors newly formed vessels, but not malignant cells, showed high VEGFR-3 expression. These data suggest that VEGF-D could contribute to leukemia and lymphoma growth via the induction of angiogenesis in bone marrow and lymphoid tissues.  相似文献   
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The purpose of this two-part study was to conduct a social validation assessment of microswitches versus interaction/stimulation conditions used with persons with multiple disabilities. In Part I, 32 teacher-assistant trainees were shown video-tapes reporting the use of microswitches versus interaction conditions for six children. In Part II, 40 teacher-assistant trainees or classroom aides and 44 rehabilitation staff were presented with video-tapes showing the use of microswitches versus systematic stimulation strategies for four adults. Raters scored the microswitch and the interaction or stimulation conditions on a 7-item questionnaire covering social/emotional and practical aspects. The microswitch condition was viewed as generally more positive than or comparable to the interaction or stimulation conditions. Main features of the findings and their implications are discussed.  相似文献   
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