[Peri-conception use of folic acid in the prevention of neural tube defect: current concepts]. / Uso periconcepcional de ácido fólico en la prevención de defectos del tubo neural: conceptos actuales.

The incidence of neural tube defects (NTDs) is about 1.3 cases per 1000 live births. The higher incidence of NTDs occurs among certain ethnic groups, and geographic areas. The fetal morbimortality is high and the treatment for those babies who live is expensive with pour quality of live. It is unclear what biochemical mechanism involving folate explain the relationship of this vitamin to the pathogenesis of NTDs. However elevated concentrations of homocysteine or decreased methionine concentrations could be interfere with closure of the neural tube. The pharmacologic periconceptional intake of 0.4-4.0 mg/day of folic acid reduces the risk of occurrent NTDs by approximately 40-75%. A relatively high dietary intake of folate may also reduce the risk.

[Peritoneal immune response in endometriosis]. / Respuesta inmune peritoneal en endometriosis.

The systematic analysis of immunity status in the peritoneum of women with endometriosis, is presented. Twenty five patients were studied, distributed as follows: A. Endometriosis, B. Sterility of non identified cause. In all the patients, peritoneal fluid was obtained (PF) during diagnostic laparoscopy, and a sample of peripheral blood was taken simultaneously. Both samples were processed analysis of lymphocytes subpopulations (ALS) by flux cytometry using monoclonal antibodies with reactivity to lymphocytes T total (CD+), lymphocytes B (CD19+), auxiliatory/inductory (CD3+CD4+), suppressor/cytotoxic (CD3+CD8+) and NK (CD3+CD16+ + 56+). The peritoneal ALS of both groups were characterized by a clear lymphocyte B diminution, moderate diminution of activators; a considerable increase of suppressors; altered CD4+/CD8+ relation in favour of suppression and NK diminution when comparing with its own blood compartment. All of these values were identical for both groups, and the only significant difference was found when comparing activated lymphocytes T subpopulation that was lesser in PF of women with endometriosis. This is the only fact that backs up the existence of altered immunity in the peritoneum of these patients, that affects the expression of activated lymphocytes. However, taking as a criterium the rest of subpopulations, in endometriosis as well as in ECNI the microenvironment goes for suppression and they are not distinguishable among them. On other side, it started signal characterization that conditions suppression induction for lymphocytes activation in peritoneal environment of women with endometriosis. Ten samples of PF of patients using peripheral purified lymphocytes by density gradient of voluntary donnors, normal, fertile, were analyzed. Cells were cultivated and stimulated in vitro with concanavaline A in presence of timidine 3H. In experimental holes PF was added at dose-response concentration, and it was evaluated as the difference in synthesis of radioactive ADN against the incubated cells in absence of PF. It was possible to demonstrate the presence of associated factors in PF of patients with endometriosis that inhibit proliferation of lymphocytes stimulated by Con A, and not so in samples of ECNI. With these factors one supposes the presence of soluble signals that condition local immunological suppression.