Bleeding complications and antithrombotic treatment in 264 pregnancies in antiphospholipid syndrome

Purpose The purpose of this study was to evaluate the safety of antithrombotic treatments prescribed during pregnancy in patients with antiphospholipid syndrome (APS). Methods This international, multicenter study included two cohorts of patients: a retrospective French cohort and a prospective US cohort (PROMISSE study). Inclusion criteria were (1) APS (Sydney criteria), (2) live pregnancy at 12 weeks of gestation (WG) with (3) follow-up data until six weeks post-partum. According to APS standard of care, patients were treated with aspirin and/or low-molecular weight heparin (LMWH) at prophylactic (pure obstetric APS) or therapeutic doses (history of thrombosis). Major bleeding was defined as abnormal blood loss during the pregnancy and/or post-partum period requiring intervention for hemostasis or transfusion, or during the peripartum period greater than 500 mL and/or requiring surgery or transfusion. Other bleeding events were classified as minor. Results Two hundred and sixty-four pregnancies (87 prospectively collected) in 204 patients were included (46% with history of thrombosis, 23% with associated systemic lupus). During pregnancy, treatment included LMWH ( n = 253; 96%) or low-dose aspirin ( n = 223; 84%), and 215 (81%) patients received both therapies. The live birth rate was 89% and 82% in the retrospective and prospective cohorts, respectively. Adverse pregnancy outcomes occurred in 28% of the retrospective cohort and in 40% of the prospective cohort. No maternal death was observed in either cohort. A combined total of 45 hemorrhagic events (25%) occurred in the retrospective cohort, but major bleeding was reported in only six pregnancies (3%). Neither heparin nor aspirin alone nor combined therapy increased the risk of hemorrhage. We also did not observe an increased rate of bleeding in the case of a short interval between last LMWH (less than 24 hours) or aspirin (less than five days) doses and delivery. Only emergency Caesarean section was significantly associated with an increased risk of bleeding (odds ratio (OR) 5.03 (1.41-17.96); p=.016). In the prospective cohort, only one minor bleeding event was reported (vaginal bleeding). Conclusion Our findings support the safety of antithrombotic therapy with aspirin and/or LMWH during pregnancy in high-risk women with APS, and highlight the need for better treatments to improve pregnancy outcomes in APS. PROMISSE Study ClinicalTrials.gov identifier: NCT00198068.

Neural Stem Cells and Fetal-Onset Hydrocephalus

Fetal-onset hydrocephalus is not only a disorder of cerebrospinal fluid (CSF) dynamics, but also a brain disorder. How can we explain the inborn and, so far, irreparable neurological impairment in children born with hydrocephalus? We hypothesize that a cell junction pathology of neural stem cells (NSC) leads to two inseparable phenomena: hydrocephalus and abnormal neurogenesis. All neurons, glial cells, and ependymal cells of the mammalian central nervous system originate from the NSC forming the ventricular zone (VZ) and the neural progenitor cells (NPC) forming the subventricular zone. Several genetic mutations and certain foreign signals all convey into a final common pathway leading to cell junction pathology of NSC and VZ disruption. VZ disruption follows a temporal and spatial pattern; it leads to aqueduct obliteration and hydrocephalus in the cerebral aqueduct, while it results in abnormal neurogenesis in the telencephalon. The disrupted NSC and NPC are released into the CSF and may transform into neurospheres displaying a junctional pathology similar to that of NSC of the disrupted VZ. These cells can then be utilized to investigate molecular alterations underlying the disease and open an avenue into possible NSC therapy.

A cell junction pathology of neural stem cells leads to abnormal neurogenesis and hydrocephalus

Most cells of the developing mammalian brain derive from the ventricular (VZ) and the subventricular (SVZ) zones. The VZ is formed by the multipotent radial glia/neural stem cells (NSCs) while the SVZ harbors the rapidly proliferative neural precursor cells (NPCs). Evidence from human and animal models indicates that the common history of hydrocephalus and brain maldevelopment starts early in embryonic life with disruption of the VZ and SVZ. We propose that a "cell junction pathology" involving adherent and gap junctions is a final common outcome of a wide range of gene mutations resulting in proteins abnormally expressed by the VZ cells undergoing disruption. Disruption of the VZ during fetal development implies the loss of NSCs whereas VZ disruption during the perinatal period implies the loss of ependyma. The process of disruption occurs in specific regions of the ventricular system and at specific stages of brain development. This explains why only certain brain structures have an abnormal development, which in turn results in a specific neurological impairment of the newborn. Disruption of the VZ of the Sylvian aqueduct (SA) leads to aqueductal stenosis and hydrocephalus, while disruption of the VZ of telencephalon impairs neurogenesis. We are currently investigating whether grafting of NSCs/neurospheres from normal rats into the CSF of hydrocephalic mutants helps to diminish/repair the outcomes of VZ disruption.

Structure and function of the ependymal barrier and diseases associated with ependyma disruption

The neuroepithelium is a germinal epithelium containing progenitor cells that produce almost all of the central nervous system cells, including the ependyma. The neuroepithelium and ependyma constitute barriers containing polarized cells covering the embryonic or mature brain ventricles, respectively; therefore, they separate the cerebrospinal fluid that fills cavities from the developing or mature brain parenchyma. As barriers, the neuroepithelium and ependyma play key roles in the central nervous system development processes and physiology. These roles depend on mechanisms related to cell polarity, sensory primary cilia, motile cilia, tight junctions, adherens junctions and gap junctions, machinery for endocytosis and molecule secretion, and water channels. Here, the role of both barriers related to the development of diseases, such as neural tube defects, ciliary dyskinesia, and hydrocephalus, is reviewed.

Mycotoxins in feedstuffs in Portugal: an overview

Mycotoxins are secondary metabolites produced by many genera of fungi in many commodities, under certain conditions. Mycotoxicological control of feed is a procedure that aims to protect human and animal health, avoiding the adverse effects of these undesirable substances. This component of the sanitary control of feed and food is essential to prevent the presence of those substances which can seriously affect the health of the animals. In Portugal, there is relatively few information related to the natural occurrence of mycotoxins in feed. In this context, the authors present results and data compilation concerning the occurrence of mycotoxins in raw materials and also feed for dairy cattle, swine, poultry, horses, fish, laboratory rats and pet; making a generic qualitative appreciation of the risks associated to the presence of mycotoxins in these feedstuffs. The mycotoxins studied: aflatoxins (AFs), ochratoxin A (OTA), fumonisin B1 and B2 (FB1, FB2) were analysed by High Performance Liquid Chromatoghraphy (HPLC). Deoxynivalenol (DON) and zearalenone (ZEN) were determined by Thin-Layer Chromatography (TLC). The results suggest that contaminations with these mycotoxins in feed are quite common, revealing the need for surveillance and monitoring programs for the prevention of the sanitary impacts of these "non desirable substances".

Amplified fragment length polymorphism (AFLP) analysis of Listeria monocytogenes

An agarose gel based single enzyme AFLP method using EcoR1 digestion of Listeria monocytogenes DNA was developed for epidemiological typing. The method was evaluated with 84 L. monocytogenes cultures, and results were compared with those obtained with serotyping, phage-typing and cadmium and arsenic resistance typing. The AFLP method was reproducible and 14 different banding patterns comprising between five and eight DNA fragments were produced. All except two of the AFLP patterns were serorype specific. Different AFLP patterns were recognised within serovar 4b (four patterns), 1/2a (two patterns), 1/2b (six patterns): single patterns were obtained from cultures of serovars 1/2c, 3a, 3b and 3c. There were associations with AFLP results and those from phage-typing and cadmium and arsenic resistance typing, although each method showed some independence. This preliminary evaluation suggests that this AFLP method will be useful for epidemiological typing of L. monocytogenes.