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41.
The genetic basis of bipolar disorder (BPD) and schizophrenia (SCZ) has been established through numerous clinical and molecular studies. Although often considered separate nosological entities, evidence now suggests that the two syndromes may share some genetic liability. Recent studies have used a composite phenotype (psychosis) that includes BPD, SCZ, psychosis not otherwise specified, and schizoaffective disorder, to identify shared susceptibility loci. Several chromosomal regions are reported to be shared between these syndromes (18p, 6q, 10p, 13q, 22q). As a part of our endeavor to scan these regions, we report a positive linkage and association finding at 18p11.2 for psychosis. Two-point linkage analysis performed on a series of 52 multiplex pedigrees with 23 polymorphic markers yielded a LOD score of 2.02 at D18S37. An independent set of 159 parent offspring trios was used to confirm this suggestive finding. The TDT analysis yielded support for association between the marker D18S453 and the disease allele (chi2 = 4.829, P < 0.028). This region has been implicated by several studies on BPD [Sjoholt et al. (2004); Mol Psychiatry 9(6):621-629; Washizuka et al. (2004); Biol Psychiatry 56(7):483-489; Pickard et al. (2005); Psychiatr Genet 15(1):37-44], SCZ [Kikuchi et al. (2003); J Med Dent Sci 50(3):225-229; Babovic-Vuksanovic et al. (2004); Am J Med Genet 124(3):318-322] and also as a shared region between the two diseases [Ishiguro et al. (2001); J Neural Transm 108(7):849-854; Reyes et al. (2002); Mol Psychiatry 7(4):337-339; Craddock et al. (2005); J Med Genet 42(3):193-204]. Our findings provide an independent validation of the above reports, and suggest the presence of susceptibility loci for psychoses in this region.  相似文献   
42.
The efficacy of monoclonal antibody (MAb 2H1) against diverse strains of Cryptococcus neoformans was studied in a murine model of intravenous infection. For six of eight strains, administration of MAb prior to infection prolonged survival of mice. For two strains, 371 and SB4A, administration of MAb prior to infection did not prolong survival in multiple experiments with inocula ranging from 10(2) to 10(6) yeast cells per mouse. Mice infected with strains 371 and SB4A had fewer CFU than non-MAb-treated controls, but the CFU reduction was not sufficient to affect survival. Serum glucuronoxylomannan (GXM) levels varied for the different C. neoformans strains. For mice that did not receive MAb 2H1, there was a positive correlation between lung fungal burden and serum GXM levels. MAb 2H1-treated mice had significantly reduced serum GXM levels. The results indicate that the efficacy of MAb 2H1 administration in prolonging survival and/or reducing organ CFU varies with the C. neoformans strain.  相似文献   
43.
The application of diffusion tensor imaging (DTI) to the evaluation of developing brain remains an area of active investigation. This review focuses on the changes in DTI parameters which accompany both brain maturation and injury. The two primary pieces of information available from DTI studies-water apparent diffusion coefficient and diffusion anisotropy measures-change dramatically during development, reflecting underlying changes in tissue water content and cytoarchitecture. DTI parameters also change in response to brain injury. In this context, not only does DTI offer the possibility of detecting injury earlier than conventional imaging methods, but also appears more sensitive to disruption of white matter than any other imaging method. DTI offers unique insight into brain injury and maturation, and does so in a fashion that can be readily applied in a clinical setting.  相似文献   
44.
Health Services and Outcomes Research Methodology - Medical insurance claims are becoming increasingly common data sources to answer a variety of questions in biomedical research. Although...  相似文献   
45.
BackgroundDamage to the renal microvasculature is a hallmark of renal ischemia-reperfusion injury (IRI)–mediated AKI. The miR-17∼92 miRNA cluster (encoding miR-17, -18a, -19a, -20a, -19b-1, and -92a-1) regulates angiogenesis in multiple settings, but no definitive role in renal endothelium during AKI pathogenesis has been established.MethodsAntibodies bound to magnetic beads were utilized to selectively enrich for renal endothelial cells from mice. Endothelial-specific miR-17∼92 knockout (miR-17∼92endo−/−) mice were generated and given renal IRI. Mice were monitored for the development of AKI using serum chemistries and histology and for renal blood flow using magnetic resonance imaging (MRI) and laser Doppler imaging. Mice were treated with miRNA mimics during renal IRI, and therapeutic efficacies were evaluated.ResultsmiR-17, -18a, -20a, -19b, and pri–miR-17∼92 are dynamically regulated in renal endothelial cells after renal IRI. miR-17∼92endo−/− exacerbates renal IRI in male and female mice. Specifically, miR-17∼92endo−/− promotes renal tubular injury, reduces renal blood flow, promotes microvascular rarefaction, increases renal oxidative stress, and promotes macrophage infiltration to injured kidneys. The potent antiangiogenic factor thrombospondin 1 (TSP1) is highly expressed in renal endothelium in miR-17∼92endo−/− after renal IRI and is a target of miR-18a and miR-19a/b. miR-17∼92 is critical in the angiogenic response after renal IRI, which treatment with miR-18a and miR-19b mimics can mitigate.ConclusionsThese data suggest that endothelial-derived miR-17∼92 stimulates a reparative response in damaged renal vasculature during renal IRI by regulating angiogenic pathways.  相似文献   
46.
MUC1 (CD227) is a large transmembrane epithelial mucin glycoprotein, which is aberrantly overexpressed in most adenocarcinomas and is a target for immune therapy for epithelial tumors. Recently, MUC1 has been detected in a variety of hematopoietic cell malignancies including T and B cell lymphomas and myelomas; however, its function in these cells is not clearly defined. Using the Jurkat T cell lymphoma cell line and normal human T cells, we demonstrate that MUC1 is not only expressed in these cells but is also phosphorylated upon T cell receptor (TCR) ligation and associates with the Src-related T cell tyrosine kinase, p56lck. Upon TCR-mediated activation of Jurkat cells, MUC1 is found in the low-density membrane fractions, where linker of T cell activation is contained. Abrogation of MUC1 expression in Jurkat cells by MUC1-specific small interfering RNA resulted in defects in TCR-mediated downstream signaling events associated with T cell activation. These include reduction in Ca2+ influx and extracellular signal-regulated kinase 1/2 phosphorylation, leading to a decrease in CD69 expression, proliferation, and interleukin-2 production. These results suggest a regulatory role of MUC1 in modulating proximal signal transduction events through its interaction with proteins of the activation complex.  相似文献   
47.
Echocardiographic determination of left ventricular mass provides prognostic information that is independent of blood pressure. This prognostic information has a graded and continuous relationship with outcome, and is independent of traditional risk factors. This article addresses the prognostic and clinical utility of echocardiography for detection of left ventricular mass. Recommendations will be offered regarding the use of echocardiography for screening in select individuals.  相似文献   
48.
49.
Cytomegalovirus infection of the colon is a late and severe complication in human immunodeficiency virus patients. Despite availability of medical treatment, occasional life-saving emergency surgery must be performed. The controversial surgical aspects of treatment are discussed based upon an unusual case of aseptic generalized peritonitis without perforation. The feasibility and value of limited resection are emphasized.  相似文献   
50.
We have synthesized N-[3-(2',4'-dichlorophenoxy)-2-18F-fluoropropyl]-N-methylpropar gylamine (18F-fluoroclorgyline) as a potential positron emission tomography (PET) radiotracer for monoamine oxidase A (MAO-A). The radiosynthesis was carried out by a 18F-fluoride-for-mesylate substitution reaction in approximately 20% radiochemical yield in specific activities of 1-2 Ci/micromol. Selectivity for MAO-A was demonstrated by the high affinity of clorgyline (IC50 = 39 nM) and lower affinity of (R)-deprenyl (IC50 > or = 100 microM) for the inhibition of 18F-fluoroclorgyline binding in vitro in rat brain membranes. The uptake of 18F-fluoroclorgyline in the rat brains was high (> 1.0% injected dose/g). The binding of 18F-fluoroclorgyline in the rat brain correlated with the distribution of MAO-A and was inhibited by preadministration of MAO-A inhibitors, clorgyline, and Ro 41-1049, whereas (R)-deprenyl, a MAO-B blocker, had no inhibitory effect. These results suggest that 18F-fluoroclorgyline is a potential PET radiotracer for MAO-A.  相似文献   
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