91 research outputs found
HTLV-1 propels thymic human T cell development in “human immune system” Rag2-/- IL-2R γc-/- Mice
Alteration of early haematopoietic development is thought to be responsible for the onset of immature leukemias and lymphomas. We have previously demonstrated that TaxHTLV-1 interferes with ß-selection, an important checkpoint of early thymopoiesis, indicating that human T-cell leukemia virus type 1 (HTLV-1) infection has the potential to perturb thymic human αβ T-cell development. To verify that inference and to clarify the impact of HTLV-1 infection on human T-cell development, we investigated the in vivo effects of HTLV-1 infection in a “Human Immune System” (HIS) Rag2-/-γc-/- mouse model. These mice were infected with HTLV-1, at a time when the three main subpopulations of human thymocytes have been detected. In all but two inoculated mice, the HTLV-1 provirus was found integrated in thymocytes; the proviral load increased with the length of the infection period. In the HTLV-1-infected mice we observed alterations in human T-cell development, the extent of which correlated with the proviral load. Thus, in the thymus of HTLV-1-infected HIS Rag2-/-γc-/- mice, mature single-positive (SP) CD4+ and CD8+ cells were most numerous, at the expense of immature and double-positive (DP) thymocytes. These SP cells also accumulated in the spleen. Human lymphocytes from thymus and spleen were activated, as shown by the expression of CD25: this activation was correlated with the presence of tax mRNA and with increased expression of NF-kB dependent genes such as bfl-1, an anti-apoptotic gene, in thymocytes. Finally, hepato-splenomegaly, lymphadenopathy and lymphoma/thymoma, in which Tax was detected, were observed in HTLV-1-infected mice, several months after HTLV-1 infection. These results demonstrate the potential of the HIS Rag2-/-γc-/- animal model to elucidate the initial steps of the leukemogenic process induced by HTLV-1
Withanolides and related steroids
Since the isolation of the first withanolides in the mid-1960s, over 600 new members of this group of compounds have been described, with most from genera of the plant family Solanaceae. The basic structure of withaferin A, a C28 ergostane with a modified side chain forming a δ-lactone between carbons 22 and 26, was considered for many years the basic template for the withanolides. Nowadays, a considerable number of related structures are also considered part of the withanolide class; among them are those containing γ-lactones in the side chain that have come to be at least as common as the δ-lactones. The reduced versions (γ and δ-lactols) are also known. Further structural variations include modified skeletons (including C27 compounds), aromatic rings and additional rings, which may coexist in a single plant species. Seasonal and geographical variations have also been described in the concentration levels and types of withanolides that may occur, especially in the Jaborosa and Salpichroa genera, and biogenetic relationships among those withanolides may be inferred from the structural variations detected. Withania is the parent genus of the withanolides and a special section is devoted to the new structures isolated from species in this genus. Following this, all other new structures are grouped by structural types.
Many withanolides have shown a variety of interesting biological activities ranging from antitumor, cytotoxic and potential cancer chemopreventive effects, to feeding deterrence for several insects as well as selective phytotoxicity towards monocotyledoneous and dicotyledoneous species. Trypanocidal, leishmanicidal, antibacterial, and antifungal activities have also been reported. A comprehensive description of the different activities and their significance has been included in this chapter. The final section is devoted to chemotaxonomic implications of withanolide distribution within the Solanaceae.
Overall, this chapter covers the advances in the chemistry and biology of withanolides over the last 16 years.Fil: Misico, Rosana Isabel. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de QuĂmica Orgánica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Unidad de Microanálisis y MĂ©todos FĂsicos Aplicados a la QuĂmica Orgánica (i); ArgentinaFil: Nicotra, V.. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico CĂłrdoba. Instituto Multidisciplinario de BiologĂa Vegetal (p); Argentina. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Departamento de QuĂmica Orgánica; ArgentinaFil: Oberti, Juan Carlos MarĂa. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico CĂłrdoba. Instituto Multidisciplinario de BiologĂa Vegetal (p); Argentina. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Departamento de QuĂmica Orgánica; ArgentinaFil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico CĂłrdoba. Instituto Multidisciplinario de BiologĂa Vegetal (p); Argentina. Universidad
Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Departamento de Farmacia; ArgentinaFil: Gil, Roberto Ricardo. University Of Carnegie Mellon; Estados UnidosFil: Burton, Gerardo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de QuĂmica Orgánica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Unidad de Microanálisis y MĂ©todos FĂsicos Aplicados a la QuĂmica Orgánica (i); Argentin
Related Donor Outcomes From the Japanese Registry – the Importance of Pre-Registration System
Synergistic Protective Effects of Antioxidant and Nitric Oxide Synthase Inhibitor in Transient Focal Ischemia
Congenital venous anomalies associated with retrocaval ureter: evaluation using computed tomography
Background: Retrocaval ureter is a rare congenital anomaly resulting from anomalous development of inferior vena cava (IVC) and not from anomalous of the ureter. The anomaly always occurs on the right side due to regression of right supracardinal vein and persistence of right posterior cardinal vein. Retrocaval ureter tends to be associated with various vena cava anomalies because of the embryogenesis. We aimed to identify the prevalence of associated congenital venous anomalies (CVA) resulting from cardinal vein development in adults with retrocaval ureter using computed tomography (CT) images.
Materials and methods: The study included 22 adults with retrocaval ureter. We evaluated CT findings and determined the incidence of associated CVA using thin slice data sets from CT scanner with 64 or more detectors. We compared the prevalence of CVA in the retrocaval ureter group (mean age: 57±19 years) and in the control group of 6189 adults with normal ureter (mean age: 66±14 years).
Results: In the retrocaval ureter group, 4 adults (18.2 %) had CVA including double IVC, right double IVC, preisthmic IVC with horseshoe kidney, and preaortic iliac confluence. One of 2 adults with preaortic iliac confluence had right double right IVC. In the control group, 49 adults (0.79%) had CVA including 37 double IVCe, 11 left IVCe, and 1 IVC interruption azygos continuation. Fifteen horseshow kidneys were found. The prevalence of associated CVA in the retrocaval ureter group was higher than that in the control group (p<0.001).
Conclusions: Retrocaval ureter is frequently associated with CVA. Various CVA with retrocaval ureter could happen because of abnormal development of not only the right posterior or supra cardinal vein but also other cardinal veins
Nonmyeloablative allogeneic stem cell transplantation as immunotherapy for pancreatic cancer and other solid tumors
Role of Nitric Oxide in the Secondary Expansion of a Cortical Brain Lesion from Cold Injury
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