Search results for "Positive"
showing 10 items of 1875 documents
CD4+ CCR5+ and CD4+ CCR3+ lymphocyte subset and monocyte apoptosis in patients with acute visceral leishmaniasis
2004
The potential involvement of apoptosis in the pathogenesis of visceral leishmaniasis (VL) was examined by studying spontaneous and Leishmania antigen (LAg)-induced apoptosis using cryopreserved peripheral blood mononuclear cells (PBMC) of Sicilian patients with VL. Results indicate that monocytes and T lymphocytes from acute VL patients show a significantly higher level of apoptosis compared with that observed in healed subjects. The percentage of apoptotic cells was higher in monocytes than in T lymphocytes. T cells involved in programmed cell death (PCD) were mainly of the CD4(+) phenotype. In particular, the T helper 1-type (Th1) subset, as evaluated by chemokine receptor-5 (CCR5) expres…
Schistosoma haematobium Infection and CD4+ T-cell levels: A cross-sectional study of young South African women
2015
Schistosoma (S.) haematobium causes urogenital schistosomiasis and has been hypothesized to adversely impact HIV transmission and progression. On the other hand it has been hypothesized that HIV could influence the manifestations of schistosomiasis. In this cross-sectional study, we explored the association between urogenital S. haematobium infection and CD4 cell counts in 792 female high-school students from randomly selected schools in rural KwaZulu-Natal, South Africa. We also investigated the association between low CD4 cell counts in HIV positive women and the number of excreted schistosome eggs in urine. Sixteen percent were HIV positive and 31% had signs of urogenital schistosomiasis…
CD28-dependent Rac1 activation is the molecular target of azathioprine in primary human CD4+ T lymphocytes
2003
Azathioprine and its metabolite 6-mercaptopurine (6-MP) are immunosuppressive drugs that are used in organ transplantation and autoimmune and chronic inflammatory diseases such as Crohn disease. However, their molecular mechanism of action is unknown. In the present study, we have identified a unique and unexpected role for azathioprine and its metabolites in the control of T cell apoptosis by modulation of Rac1 activation upon CD28 costimulation. We found that azathioprine and its metabolites induced apoptosis of T cells from patients with Crohn disease and control patients. Apoptosis induction required costimulation with CD28 and was mediated by specific block- ade of Rac1 activation thro…
CD4+ and CD8+ clonal T cell expansions indicate a role of antigens in ankylosing spondylitis; a study in HLA-B27+ monozygotic twins.
2001
SUMMARYAnkylosing spondylitis (AS) is a complex genetic disease in which both MHC and non-MHC genes determine disease susceptibility. To determine whether the T cell repertoires of individuals with AS show signs of increased stimulation by exogenous antigens, CD4+ and CD8+ T cell subsets of five monozygotic HLA-B27+ twins (two concordant and three discordant for AS) and CD8+ T cell repertoires of three healthy HLA-B27+ individuals were characterized by TCR β-chain (TCRB) CDR3 size spectratyping. Selected TCRB-CDR3 spectra were further analysed by BJ-segment analysis and TCRB-CDR3 from expanded T cell clones were sequenced. In an analysis of all data (519/598 possible TCRB-CDR3 spectra), AS …
Azathioprine suppresses ezrin-radixin-moesin-dependent T cell-APC conjugation through inhibition of Vav guanosine exchange activity on rac proteins
2006
Abstract We have shown recently that the azathioprine metabolite 6-Thio-GTP causes immunosuppression by blockade of GTPase activation in T lymphocytes. In the present study, we describe a new molecular mechanism by which 6-Thio-GTP blocks GTPase activation. Although 6-Thio-GTP could bind to various small GTPases, it specifically blocked activation of Rac1 and Rac2 but not of closely related Rho family members such as Cdc42 and RhoA in primary T cells upon stimulation with αCD28 or fibronectin. Binding of 6-Thio-GTP to Rac1 did not suppress Rac effector coupling directly but blocked Vav1 exchange activity upon 6-Thio-GTP hydrolysis, suggesting that 6-Thio-GTP loading leads to accumulation of…
Increase of CCR7- CD45RA+ CD8 T cells (TEMRA) in Chronic Graft-versus-host Disease
2006
Among the late effects of hematopoietic stem cell transplantation (HSCT), chronic graft-vs-host disease (cGVHD) still remains as the major determinant of long-term outcome and quality of life. The disease typically appears between 3 months to 1.5 years following an allogeneic transplantation and is characterized by symptoms similar to those of autoimmune disease.
Measurement Invariance of the Scale of Positive and Negative Experience Across 13 Countries
2022
The Scale of Positive and Negative Experience (SPANE) is widely used to measure emotional experiences, but not much is known about its cross-cultural utility. The present study evaluated the measurement invariance of the SPANE across adult samples (N = 12,635; age range = 18-85 years; 58.2% female) from 13 countries (China, Colombia, Germany, Greece, India, Italy, Japan, Poland, Portugal, Serbia, Spain, Turkey, and the United States). Configural and partial scalar invariance of the SPANE were supported. Three items capturing specific negative emotions (sad, afraid, and angry) were found to be culturally noninvariant. Our findings suggest that the SPANE's positive emotion terms and general n…
Assessing positive body image, body satisfaction, weight bias, and appearance comparison in emerging adults: A cross-validation study across eight co…
2020
Positive body image refers to individuals' ability to conceptualize their bodies with love, respect, and appreciation. The study of positive body image is relatively new, and instruments used to investigate this multi-faceted construct have received limited use in non-English speaking countries. Thus, the aim of this investigation is to consider four measures that are associated with positive body image across eight different countries. Participants (n = 6272) completed the Body Appreciation Scale-2, the Body Areas Satisfaction Scale, the Physical Appearance Comparison Scale, and the Weight Bias Internalization Scale. Multi-group confirmatory factor analyses (MG-CFAs) and item-response theo…
Rapid High Efficiency Sensitization of CD8+ T Cells to Tumor Antigens by Dendritic Cells Leads to Enhanced Functional Avidity and Direct Tumor Recogn…
2003
Abstract Myeloid-origin dendritic cells (DCs) can develop into IL-12-secreting DC1 or non-IL-12-secreting DC2 depending on signals received during maturation. Through rapid culture techniques that prepared either mature, CD83+ DC1 or DC2 from CD14+ monocytes in only 2 days followed by a single 6–7 day DC-T cell coculture, we sensitized normal donor CD8+ T cells to tumor Ags (HER-2/neu, MART-1, and gp100) such that peptide Ag-specific lymphocytes constituted up to 16% of the total CD8+ population. Both DC1 and DC2 could sensitize CD8+ T cells that recognized peptide-pulsed target cells. However, with DC2, a general decoupling was observed between recognition of peptide-pulsed T2 target cells…
Diagnostic Accuracy of Fecal Calprotectin Assay in Distinguishing Organic Causes of Chronic Diarrhea from Irritable Bowel Syndrome: A Prospective Stu…
2003
AbstractBackground: Fecal calprotectin (FC) has been proposed as a marker of inflammatory bowel disease (IBD), but few studies have evaluated its usefulness in patients with chronic diarrhea of various causes. We evaluated the diagnostic accuracy of a FC assay in identifying “organic” causes of chronic diarrhea in consecutive adults and children.Methods: We consecutively enrolled 70 adult patients (30 males, 40 females; median age, 35 years) and 50 children (20 males, 30 females; median age, 3.5 years) with chronic diarrhea of unknown origin. All patients underwent a complete work-up to identify the causes of chronic diarrhea. FC was measured by ELISA.Results: In adult patients, FC showed 6…