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Preeclampsia (PE) is a major health problem occurring in pregnant women and the principal cause of maternal morbidity and perinatal mortality. It is characterized by alteration of the extravilli trophoblast cell migration toward the endometrial spiral arteries with a concomitant reduction in maternal blood flow in the placenta. This result in a state of ischemia–hypoxia which triggers an oxidative stress stage with production of reactive oxygen species. A cascade of cellular and molecular events leads then to endothelial dysfunction, transduction pathway signal disruption and induction of apoptosis and necrosis mechanisms and therefore a significant reduction in the amount of nutrients required for normal fetal development. Placental anchoring chorionic and stem villi present a skeleton of myofibroblasts arranged in parallel disposition to its longitudinal axis. The intraplacental blood volume is controlled by the contraction/relaxation of these myofibroblasts, promoting the delivery of nutrients and metabolites to the fetus. Recently, a new mesodermal originated cell type has been described in the villous stroma, the so named “telocytes”. These cells are strategically located between the smooth muscle cells of the blood vessel wall and the myofibroblasts, and it is reasonable to hypothesize that they may play a pacemaker role, as in the intestine. This study provide new information supporting the notion that the occurrence of oxidative stress in PE is not only related to endothelial dysfunction and apoptosis of the trophoblast cells, but also involves telocytes and its putative role in the regulation of fetal blood flow and the intra-placental blood volume. Some ideas aimed at dilucidating the relationship between placental failure and the behavior of telocytes in pathological organs in adulthood, are also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Chagas’ disease, produced by the haemoflagellated protozoan Trypanosoma cruzi (T. cruzi), is one of the most frequent endemic diseases in Latin America. In spite that in the past few years T. cruzi congenital transmission has become of epidemiological importance, studies about this mechanism of infection are scarce. The placental tissue undergoes apoptosis throughout gestation, as part of its normal turnover. On the other hand, it is known that T. cruzi induces, delays or inhibits apoptosis in other mammalian tissues. In order to determine the effect of parasite invasion on normal apoptosis in the placenta, explants of human chorionic villi were incubated with 105 trypomastigotes for 24 h. Effective infection was tested by visualizing T. cruzi antigens in histological preparations and by PCR. Upon infection, apoptotic cell death was determined by light and transmission electron microscopy, TUNEL analysis, measurement of caspase-3 like activity and immunohistochemical detection of caspase 3 cleaved cytokeratin 18. Our results clearly show that T. cruzi induces apoptosis in the chorionic villi and suggest that this is one of mechanisms used by the parasite to insure infection and invasion of human placenta and fetus. [Copyright &y& Elsevier]

Abstract: Congenital Chagas’ disease, endemic in Latin America and also present with lower frequency in other countries, is associated with premature labor, miscarriage, and placentitis. The mechanism of tissue invasion and infection of human placenta by the parasite Trypanosoma cruzi (T. cruzi) remains unclear. In order to explore some morphological aspects of this infection in the placenta, we incubated chorionic villous explants from normal human placentae ex vivo with the parasite and studied the resulting effects by immunohistochemical and histochemical methods. Infection of the chorionic villi with the parasite was confirmed by immunofluoresence and PCR. T. cruzi induces syncytiotrophoblast destruction and detachment, selective disorganization of basal lamina and disorganization of collagen I in the connective tissue of villous stroma. These effects are a function of the number of parasites used for the infection. Our results suggest a participation of the proteolytic activity of the parasite on the placental basal lamina and connective tissue in the mechanism of infection of the fetus by T. cruzi. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effects of single and combined deficiencies of Se, Zn and I on thyroid function in rats. Rats were fed amino acid-based diets for 6 wk starting from weaning. The diets contained either low or adequate amounts of these minerals. In addition to the control and control pair-fed groups, seven experimental groups were formed: Se deficient (Se-); I deficient (I-); Zn deficient (Zn-); Se and I deficient (Se-I-); Zn and I deficient (Zn-I-); Se and Zn deficient (Se-Zn); and Se, I and Zn deficient (Se-I-Zn-). Serum triiodothyronine (T3) was significantly lower than in controls in Zn-, Se-Zn- and Se-I- groups. Serum total thyroxine (T4) and free T4 were significantly lower and thyroid-stimulating hormone (TSH) greater in all iodine-deficient groups, regardless of Se or Zn status. Thyroid glutathione peroxidase activity was significantly reduced in Se- and Se-Zn- groups. Nevertheless, in the groups with a concurrent I deficiency, the activity of this enzyme was significantly greater than in controls. Severe alterations of the follicle cellular architecture, including signs compatible with apoptosis, were observed in the Zn- and Se-Zn- groups. These alterations appeared to be less severe when iodine deficiency was simultaneously present. Single and multiple deficiencies of Se, Zn and I have distinct effects on thyroid metabolism and structure. [ABSTRACT FROM AUTHOR]

In this study, an LC–MS/MS EPI method was developed for simultaneous determination of 32 toxic natural substances in herbal products. The analytes include aconite alkaloids, lobelia alkaloids, solanaceous alkaloids, digitalis steroid glycosides, strychnine, tetrahydropalmatine etc. They werecommonly used in herbal products. The target analytes were extracted from the samples using theQuEChERS method and analysed using AB SCIEX QTRAP 5500 coupled with Agilent HPLC 1260. Thecolumn used was biphenyl reversed phase analytical column. Mobile phase A and B were deionizedwater and methanol respectively, both containing 5 mM ammonium formate and 0.1% formic acid. TheMRM-IDA-EPI method enabled quantification and confirmation of the analytes in a single run. The EPIwas used for the qualitative analysis while the MRM was used for the quantitative analysis. Limits ofdetection were determined to be below 10 μg/kg for the majority of the analytes. The recoveries forthose commonly detected natural substances were in the acceptable range of 70–120%. [ABSTRACT FROM AUTHOR]

Abstract: Prediction of subsequent leukemia-free survival (LFS) and chronic graft-versus-host disease (GVHD) in adults with acute leukemia who survived at least 1 year after allogeneic hematopoietic cell transplantation is difficult. We analyzed 3339 patients with acute myeloid leukemia and 1434 patients with acute lymphoblastic leukemia who received myeloablative conditioning and related or unrelated stem cells from 1990 to 2005. Most clinical factors predictive of LFS in 1-year survivors were no longer significant after 2 or more years. For acute myeloid leukemia, only disease status (beyond first complete remission) remained a significant adverse risk factor for LFS 2 or more years after transplantation. For lymphoblastic leukemia, only extensive chronic GVHD remained a significant adverse predictor of LFS in the second and subsequent years. For patients surviving for 1 year without disease relapse or extensive chronic GVHD, the risk of developing extensive chronic GVHD in the next year was 4% if no risk factors were present and higher if noncyclosporine-based GVHD prophylaxis, an HLA-mismatched donor, or peripheral blood stem cells were used. Estimates for subsequent LFS and extensive chronic GVHD can be derived for individual patients or populations using an online calculator (http://www.cibmtr.org/LeukemiaCalculators). This prognostic information is more relevant for survivors than estimates provided before transplantation. [Copyright &y& Elsevier]

Abstract: A health supplement used for sexual performance enhancement was sent to Health Sciences Authority of Singapore for testing. An unknown compound was detected and isolated and its structure was elucidated using NMR, high-resolution MS, ESI-MS/MS, UV and IR. The compound, dapoxetine, is reported to be a selective serotonin reuptake inhibitor under investigation for the treatment of premature ejaculation. [Copyright &y& Elsevier]

Abstract: A PDE-5 inhibitor was detected and isolated from a health supplement claimed to be a preparation of fresh oyster extracts and be able to promote and support healthy sexual function and endurance, etc. The structure of this PDE-5 inhibitor was elucidated using LC–UV, LC–TOF-MS, MS–MS, IR spectroscopy, and 2D NMR. It was characterized as 8-(2-(4-(hydroxymethyl)piperidin-1-yl)benzylamino)-3-ethyl-1H-imidazo[4,5-g]quinazoline-2(3H)-thione, a compound reported to be a PDE-5 inhibitor. [Copyright &y& Elsevier]