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51.
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BACKGROUND: Assays that detect human T-lymphotropic virus type I and type II antibody (HTLV-I/II) are widely used in the routine screening of blood donors. STUDY DESIGN AND METHODS: Four commercially available anti-HTLV-I (Fujirebio and Organon Teknika) or -HTLV-I/II assays (Murex and Ortho) were evaluated in various serum panels: A) HTLV-I-positive specimens (n = 41), confirmed by Western blot and polymerase chain reaction; B) a commercially available anti-HTLV-I/II panel; C) serial dilutions of sera from HTLV-I-positive individuals (n = 30), confirmed by immunofluorescence assay and Western blot: D) serial dilutions of HTLV-II-positive blood donors (n = 20), confirmed by Western blot and polymerase chain reaction, and E) sera from first-time blood donors (n = 1055). RESULTS: All four assays elicited reactions in all 82 HTLV-I- positive samples in Panels A, B, and C. Of 32 HTLV-II-positive specimens in Panels B and D, 31 (96.9%) reacted in the Organon Teknika assay and all 32 reacted in the remaining tests. Probit analysis of test results in Panels C and D indicated that the Fujirebio test was the most sensitive assay, followed by Organon Teknika, Ortho, and Murex. The specificities of Fujirebio, Murex, Organon Teknika, and Ortho tests in 1055 first-time blood donors were 99.9, 100, 99.6, and 99.9 percent, respectively. CONCLUSION: All four studied assays for detecting HTLV-I or HTLV-I/II antibodies are appropriate as screening tests.  相似文献   
53.
Metabolic adaptation is considered an emerging hallmark of cancer, whereby cancer cells exhibit high rates of glucose consumption with consequent lactate production. To ensure rapid efflux of lactate, most cancer cells express high levels of monocarboxylate transporters (MCTs), which therefore may constitute suitable therapeutic targets. The impact of MCT inhibition, along with the clinical impact of altered cellular metabolism during prostate cancer (PCa) initiation and progression, has not been described. Using a large cohort of human prostate tissues of different grades, in silico data, in vitro and ex vivo studies, we demonstrate the metabolic heterogeneity of PCa and its clinical relevance. We show an increased glycolytic phenotype in advanced stages of PCa and its correlation with poor prognosis. Finally, we present evidence supporting MCTs as suitable targets in PCa, affecting not only cancer cell proliferation and survival but also the expression of a number of hypoxia‐inducible factor target genes associated with poor prognosis. Herein, we suggest that patients with highly glycolytic tumours have poorer outcome, supporting the notion of targeting glycolytic tumour cells in prostate cancer through the use of MCT inhibitors. © 2015 Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
54.
HIV cross-sectional studies were conducted among high-risk populations in 9 countries of South America. Enzyme-linked immunosorbent assay screening and Western blot confirmatory testing were performed, and env heteroduplex mobility assay genotyping and DNA sequencing were performed on a subset of HIV-positive subjects. HIV prevalences were highest among men who have sex with men (MSM; 2.0%-27.8%) and were found to be associated with multiple partners, noninjection drug use (non-IDU), and sexually transmitted infections (STIs). By comparison, much lower prevalences were noted among female commercial sex workers (FCSWs; 0%-6.3%) and were associated mainly with a prior IDU and STI history. Env subtype B predominated among MSM throughout the region (more than 90% of strains), whereas env subtype F predominated among FCSWs in Argentina and male commercial sex workers in Uruguay (more than 50% of strains). A renewed effort in controlling STIs, especially among MSM groups, could significantly lessen the impact of the HIV epidemic in South America.  相似文献   
55.
56.
Dectin-1 is a pathogen-recognition receptor on macrophages (MPhis), neutrophils, and dendritic cells (DCs). On MPhis and bone marrow-derived DCs, it has been shown to mediate the nonopsonic recognition of and response to soluble and particulate yeast beta-glucans. We have optimized the immunohistochemical detection of Dectin-1 and demonstrated its expression on neutrophils, subpopulations of MPhis in splenic red and white pulp, alveolar MPhis, Kupffer cells, and MPhis and DCs in the lamina propria of gut villi. This is consistent with its role in pathogen surveillance. A significant proportion of CD11c(+) splenic DCs expressed Dectin-1, but expression was not restricted to any one subset. Dectin-1 expression was low on resident MPhis and DCs of skin and was not detected on resident MPhis or DCs in kidney, heart, brain, or eye. The proposed, additional role of Dectin-1 as a coreceptor for T cell activation is supported by its expression on DCs in the T cell areas of the spleen and lymph nodes. Strong expression of Dectin-1 on subpopulations of MPhis and DCs in the medullary and corticomedullary regions of the thymus suggests a role distinct from pathogen recognition. Tissue localization thus revealed potential roles of Dectin-1 in leukocyte interactions during innate immune responses and T cell development.  相似文献   
57.
BACKGROUND: Little is known about how continuation and maintenance cognitive-behavioural therapy (CBT) influences important psychological constructs that may be associated with long-term outcome of major depressive disorder. The goal of this study was to examine whether CBT would help maintain attributional style changes experienced by patients during acute phase fluoxetine treatment. METHOD: Three hundred and ninety-one patients with major depressive disorder were enrolled in an open, fixed-dose 8 week fluoxetine trial. Remitters to this acute phase treatment (N= 132) were randomized to receive either fixed-dose fluoxetine (meds only) or fixed-dose fluoxetine plus cognitive-behavioural therapy (CBT+meds) during a 6-month continuation treatment phase. The Attributional Style Questionnaire (ASQ) was completed by patients at three time points - acute phase baseline, continuation phase baseline and continuation phase endpoint. Analysis of covariance was used to compare continuation phase ASQ composite score changes between groups. RESULTS: Patients in both treatment groups experienced significant gains in positive attributional style during the acute phase of treatment. Continuation phase ASQ composite change scores differed significantly between treatment groups, with the CBT + meds group maintaining acute phase positive attributional style changes, and the meds only group exhibiting a worsening of attributional style. The two treatment groups did not significantly differ in rates of relapse and final continuation phase visit HAMD-17 scores. CONCLUSIONS: In this sample, the addition of CBT to continuation psychopharmacological treatment was associated with maintenance of acute treatment phase attributional style gains. Further research is needed to evaluate the role of such gains in the long-term course of depressive illness.  相似文献   
58.
Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus is determined by a combination of environmental and genetic factors, which include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2 cannot explain the clustering of type 1 diabetes in families, and a role for other genes is inferred. In the present report we describe linkage and association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong candidate gene for T cell- mediated autoimmune disease because it encodes a T cell receptor that mediates T cell apoptosis and is a vital negative regulator of T cell activation. In addition, we provide supporting evidence that CTLA-4 is associated with susceptibility to Graves' disease, another organ- specific autoimmune disease.   相似文献   
59.
Development of biochips containing living cells for biodetection, drug screening and tissue engineering applications is limited by a lack of reconfigurable material interfaces and actuators. Here we describe a new class of nanostructured magnetizable materials created with a femtosecond laser surface etching technique that function as multiplexed magnetic field gradient concentrators. When combined with magnetic microbeads coated with cell adhesion ligands, these materials form microarrays of 'virtual' adhesive islands that can support cell attachment, resist cell traction forces and maintain cell viability. A cell death (apoptosis) response can then be actuated on command by removing the applied magnetic field, thereby causing cell retraction, rounding and detachment. This simple technology may be used to create reconfigurable interfaces that allow users to selectively discard contaminated or exhausted cellular sensor elements, and to replace them with new living cellular components for continued operation in future biomedical microdevices and biodetectors.  相似文献   
60.
Stoppa‐Vaucher S, Ayabe T, Paquette J, Patey N, Francoeur D, Vuissoz J‐M, Deladoëy J, Samuels ME, Ogata T, Deal CL. 46, XY gonadal dysgenesis: new SRY point mutation in two siblings with paternal germ line mosaicism. Familial recurrence risks are poorly understood in cases of de novo mutations. In the event of parental germ line mosaicism, recurrence risks can be higher than generally appreciated, with implications for genetic counseling and clinical practice. In the course of treating a female with pubertal delay and hypergonadotropic hypogonadism, we identified a new missense mutation in the SRY gene, leading to somatic feminization of this karyotypically normal XY individual. We tested a younger sister despite a normal onset of puberty, who also possessed an XY karyotype and the same SRY mutation. Imaging studies in the sister revealed an ovarian tumor, which was removed. DNA from the father's blood possessed the wild type SRY sequence, and paternity testing was consistent with the given family structure. A brother was 46, XY with a wild type SRY sequence strongly suggesting paternal Y‐chromosome germline mosaicism for the mutation. In disorders of sexual development (DSDs), early diagnosis is critical for optimal psychological development of the affected patients. In this case, preventive karyotypic screening allowed early diagnosis of a gonadal tumor in the sibling prior to the age of normal puberty. Our results suggest that cytological or molecular diagnosis should be applied for siblings of an affected DSD individual.  相似文献   
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