The chemical investigation of the extract of the dried leaves of Rauvolfia caffra (Sond) (synonym Rauvolfia macrophylla) (Apocynaceae) led to isolation of a new glycoside derivative, rauvolfianine (1) as well as six known compounds: oleanolic acid (2), sitosterol-3-O-β-D-glucopyranoside (3), betulinic acid (4), vellosimine (5), sarpagine (6) and D-fructofuranosyl-β-(2→1)-α-D-glucopyranoside (7). Compounds 1, 2, 3, 4 and 7 were evaluated for antitubercular activity. Compounds 1 and 2 were the most active (MIC = 7.
View Article and Find Full Text PDFA new medical field, known as regeneration medicine, is developing and attracting more and more researchers and practitioners. Whereas hematopoietic cell-based therapies have already proven their efficacy in numerous--malignant or not--diseases, non-hematopoietic cell-based therapies have not. They can be useful to dozens, if not hundreds, of patients with various disorders, such as cardiopathy, diabetes, some types of cancer, osteoarticular and neurodegenerative disorders.
View Article and Find Full Text PDFPerforin (P), Granzyme B (GB) and Fas-Ligand (FAS-L) are cytotoxic molecules involved in acute rejection (AR) after renal transplantation. A noninvasive diagnostic test to monitor AR and other complications could improve clinical management. We investigated the predictive and diagnostic interest of target mRNA measurements, with a quantitative PCR assay, in AR, as well as in other clinical complications recurrent in kidney transplantation.
View Article and Find Full Text PDFVascular endothelial cells are the first interface between donor and recipient in organ transplantation. Endothelial cells and smooth muscle cells are key actors of acute and chronic rejection processes in organ allografting, but they also have the capacity to protect themselves from allograft-induced injury. Recent advances in our understanding of the precise mechanisms leading to endothelial dysfunction or, on the contrary, to endothelial protection, suggest that therapeutic interventions targeting endothelial cells could improve allograft survival and have even raised the question of whether such manipulations can be considered with a view to inducing immunological tolerance.
View Article and Find Full Text PDFThe combination of 8-methoxypsoralen (8-MOP) and long wave ultraviolet radiation (UV-A) has immunomodulatory effects and might abolish both graft-vs-host and host-vs-graft reactions after allogeneic hematopoietic stem cell transplantation. In the present study, we have confirmed the sensitivity of T lymphocytes to 8-MOP treatment plus UV-A exposure as evidenced by the abrogation of the alloreactivity in mixed lymphocyte cultures as well as the inhibition of the response to phytohemagglutinin A. However, the clonogenic capacity of the bone marrow hematopoietic progenitors was inhibited with UV-A doses lower than the doses needed to inhibit T-lymphocytes alloreactivity.
View Article and Find Full Text PDFObjective: We hypothesized that the presence of tumor cells in bone marrow (BM) could alter hematopoietic progenitor cell functions. Therefore, we evaluated phenotypic and in vitro functional properties of BM-derived CD34+ progenitors issued from untreated and newly diagnosed patients presenting a mature B-lymphoproliferative disorder (LPD) involving the BM (Inv+).
Patients And Methods: In vitro proliferation and differentiation capacities of primitive and committed progenitors were evaluated by cobblestone area-forming cell (CAFC) and colony-forming cell (CFC) assays, and ex vivo cell expansion.
Transfus Apher Sci
October 2004
In 1993 by law, in France, haemovigilance became a national system of surveillance and alert, from blood collection to the follow-up of the recipients, gathering and analysing all adverse events of blood transfusion in order to prevent their recurrences. In 2003, 2911 incidents with strong imputability have been specially analysed, among them seven confirmed cases of bacterial contamination, 137 incorrect blood components transfused with 12 cases of ABO incompatibility, 15 adverse reactions diagnosed as TRALI and 12 deaths. The analysis of information provided by haemovigilance has led to the implementation of new guidelines.
View Article and Find Full Text PDFThe ultimate objective of organ transplantation is to obtain a state of tolerance, i.e. long-term acceptance of the graft without immunosuppressive therapy in order to limit the complications of these treatments (viral infections, tumours, etc.
View Article and Find Full Text PDFAmong the mechanisms capable of inducing peripheral tolerance, regulatory (suppressor) T cells (Treg) probably play a key role in the control of both reactivity to self-antigens and alloimmune response. Augmentation or manipulation of Treg could improve organ allograft survival or control graft-versus-host disease, thus resulting in operational tolerance. The role of this immunomanipulation as one method of inducing tolerance has yet to be clearly defined.
View Article and Find Full Text PDFDonor allorecognition of the recipient after hematopoietic transplantation can result in graft-versus-host disease, a potent graft-vs-leukemia effect as well as a graft facilitation effect. Danger signals, host Ag-presenting cells and minor histocompatibility Ag have recently emerged as major determinants of such an alloreactivity. A better understanding of the involved immune mechanisms, the development of novel immunomonitoring tools and cell engineering approaches should result in a significantly increased therapeutic index of allogeneic alloreactivity.
View Article and Find Full Text PDFBackground: Cellular cardiomyoplasty is a promising approach to improve postinfarcted cardiac function. The differentiation pathways of engrafted mesenchymal progenitor cells (MPCs) and their effects on the left ventricular function in a rat myocardial infarct heart model were analyzed.
Methods And Results: A ligation model of left coronary artery of Lewis rats was used.
Human bone marrow mesenchymal stem cells (MSC) generate, via a fibroblast colony-forming unit (CFU-F), osteo-chondroblastic cells as well as adipocytes and stromacytes. To date, these stem cells are isolated indirectly using a cell culture method and phenotyped as CD45 negative while the in vivo counterparts are undetermined. Our aim was to develop a direct selection method and to determine the phenotype of the MSC isolated in this way.
View Article and Find Full Text PDFThe use of hematopoietic stem-cell (HSC) therapy in organ transplantation is a challenge to promote chimerism with the aim of enhancing organ tolerance. Several HSC sources are available, including bone marrow (most of the time), peripheral blood after stem-cell mobilization, and placental blood. HSC collection techniques from vertebral bodies or iliac crests require a number of complex manipulations.
View Article and Find Full Text PDFPurpose: To analyze the difficulties involved in managing an episode of bacterial contamination in a cornea bank. We describe (1) the circumstances of bacterial contamination discovery, (2) the methods used to investigate the outbreak, (3) the corrective measures adopted, and (4) the method introduced to improve the reaction capacity in case of bacterial contamination.
Methods: All the samples collected were cultured in an attempt to identify the environmental reservoir of the contaminated epidemic clone.
Background: Gene transfer using retroviral transduction offers the advantage of long-term transgene expression in developing strategies that use dendritic cells (DCs) for immunotherapy. The goal of this study was to infect DCs in an immature state in order to take advantage of their proliferating and tolerogenic potential.
Methods: Immature DCs were generated from murine bone marrow (BM) using either GM-CSF alone or GM-CSF plus IL-4.
Background: Hemovigilance networks have been introduced in several countries to improve knowledge of blood transfusion-related morbidity and mortality. The general organization of the French network and its results from 1994 through March 1999 are presented here.
Study Design And Methods: The hemovigilance network relies on blood transfusion centers and hospital correspondents, who analyze unexpected and untoward blood transfusion-related effects and transmit a Transfusion Incident Report (TIR) to a national database (Transfusion Incident Reports Electronic Data Management [GIFIT]).
The creation of the Etablissement Français du Sang (EFS) was mentioned in the Law of July 1, 1998, pertaining to sanitary safety. The EFS is the sole operator of blood transfusion. With a unique legal status, supervised by the Ministry in charge of Health, the EFS organizes the activities involved in the transfusion chain over the whole territory, it promotes research activities and take part in international scientific cooperation.
View Article and Find Full Text PDFBackground: Gene-transfer techniques are commonly employed for both in vitro and in vivo studies. However, modifications of the target cell following the introduction of the gene of interest are not often examined. These modifications can alter the immunogenicity and/or the susceptibility of the target cell to apoptosis and may produce unwanted consequences in vivo.
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