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Late Fetal Deaths (late + fetal_death)
Selected AbstractsMutations in the thrombomodulin and endothelial protein C receptor genes in women with late fetal lossBRITISH JOURNAL OF HAEMATOLOGY, Issue 3 2001Franca Franchi Late fetal loss can be associated with placental insufficiency and coagulation defects. Thrombomodulin (TM) and the endothelial protein C receptor (EPCR) are glycoprotein receptors expressed mainly on the endothelial surface of blood vessels and also in the placenta; they both play a key physiological role in the protein C anticoagulant pathway. Defects in these proteins might play an important role in the pathogenesis of late fetal loss. We performed a case,control study in 95 women with unexplained late fetal loss (> 20 weeks), to elucidate whether TM or EPCR gene mutations were associated with an increased risk for this complication of pregnancy. The control group comprised 236 women who gave birth to at least one healthy baby and had no history of late fetal death or obstetrical complications. The entire TM and EPCR genes, including the promoter region, were screened. In total, five mutations were identified in the TM gene in 95 patients and three in 236 control subjects, and two mutations were identified in the EPCR gene in 95 patients and one in 236 control subjects. The relative risk for late fetal loss when having a mutation in the TM or EPCR gene was estimated by an odds ratio of 4·0 (95% CI 1·1,14·9). In conclusion, identified mutations in the TM and EPCR genes of women with unexplained fetal loss are more prevalent compared with women with no obstetrical complications. [source] Developmental toxicity evaluation of inhaled tertiary amyl methyl ether in mice and ratsJOURNAL OF APPLIED TOXICOLOGY, Issue 6 2003Frank Welsch Abstract This evaluation was part of a much more comprehensive testing program to characterize the mammalian toxicity potential of the gasoline oxygenator additive tertiary amyl methyl ether (TAME), and was initiated upon a regulatory agency mandate. A developmental toxicity hazard identi,cation study was conducted by TAME vapor inhalation exposure in two pregnant rodent species. Timed-pregnant CD®(Sprague-Dawley) rats and CD-1® mice, 25 animals per group, inhaled TAME vapors containing 0, 250, 1500 or 3500 ppm for 6 h a day on gestational days 6,16 (mice) or 6,19 (rats). The developmental toxicity hazard potential was evaluated following the study design draft guidelines and end points proposed by the United States Environmental Protection Agency. Based on maternal body weight changes during pregnancy, the no-observable-adverse-effect level (NOAEL) was 250 ppm for maternal toxicity in rats and 1500 ppm for developmental toxicity in rats using the criterion of near-term fetal body weights. In mice, more profound developmental toxicity was present than in rats, at both 1500 and 3500 ppm. At the highest concentration, mouse litters revealed more late fetal deaths, signi,cantly reduced fetal body weights per litter and increased incidences of cleft palate (classi,ed as an external malformation), as well as enlarged lateral ventricles of the cerebrum (a visceral variation). At 1500 ppm, mouse fetuses also exhibited an increased incidence of cleft palate and the dam body weights were reduced. Therefore, the NOAEL for the mouse maternal and developmental toxicity was 250 ppm under the conditions of this study. Copyright © 2003 John Wiley & Sons, Ltd. [source] Functional neuroanatomy of the human pre-Bötzinger complex with particular reference to sudden unexplained perinatal and infant deathNEUROPATHOLOGY, Issue 1 2008Anna M. Lavezzi The authors are the first to identify in man the pre-Bötzinger complex, a structure of the brainstem critical for respiratory rhythmogenesis, previously investigated only in rats. The evaluation of the neurokinin 1 receptors and somatostatin immunoreactivity in a total of 63 brains from 25 fetuses, nine newborns and 29 infants, allowed to delineate the anatomic structure and the boundaries of this human neural center in a restricted area of the ventrolateral medulla at the obex level, ventral to the semicompact ambiguus nucleus. The neurons of the pre-Bötzinger complex were roundish in fetuses before 30 gestational weeks and lengthened after birth, embedded in a dendritic system belonging to the reticular formation. Besides, structural and/or functional alterations of the pre-Bötzinger complex were present in a high percentage of sudden deaths (47%), prevalent in late fetal deaths. In particular, different developmental defects (hypoplasia with a decreased neuronal number and/or dendritic hypodevelopment of the reticular formation, abnormal neuronal morphology, immunonegativity of neurotransmitters, and agenesis) were found. The authors suggest that the pre-Bötzinger complex contains a variety of neurons not only involved in respiratory rhythm generation, but more extensively, essential to the control of all vital functions. Sudden death and in particular sudden unexpected fetal death could therefore be ascribed to a selective process when developmental alterations of the pre-Bötzinger complex arise. [source] Pregnancy outcome distribution and prenatal diagnosis of autosomal abnormalities, Hawaii, 1986-1999BIRTH DEFECTS RESEARCH, Issue S1 2002Mathias B. Forrester Background Approximately 10% of birth defects result from chromosomal abnormalities. This study investigated the pregnancy outcome distribution of autosomal abnormalities and impact of prenatal diagnosis on autosomal abnormalities. Methods Data were obtained from a population-based birth defects registry and included all autosomal abnormalities delivered in Hawaii during 1986-1999. Results There were 1,015 autosomal abnormality cases, consisting of 523 (52%) live births, 38 (4%) late fetal deaths, 187 (18%) early fetal deaths, 265 (26%) elective terminations, and 2 unknown pregnancy outcome. Live births comprised the majority of translocations (81%), inversions (93%), and deletions (84%) but a smaller proportion of trisomies (42%). Autosomal abnormalities were prenatally diagnosed in 489 (48%) of the cases, of which 243 (50%) were subsequently electively terminated. By type of autosomal abnormality, prenatal diagnosis rates were trisomy (44%), translocation (68%), inversion (91%), deletion (29%), and subsequent elective termination rates were trisomy (73%), translocation (11%), inversion (4%), deletion (50%). The prenatal diagnosis rate was higher for maternal age 35 years or greater than for maternal age less than 35 years (relative risk (RR) 1.8, 95% confidence interval (CI) 1.6-2.0), as was the elective termination rate (RR 1.3, 95% CI 1.1-1.6). The prenatal diagnosis rate was higher in 1993-1999 than in 1986-1992 (RR 1.2, 95% CI 1.1-1.4), although there was no statistically significant difference between the two time periods for subsequent elective termination rate (RR 0.9, 95% CI 0.8-1.1). Conclusions Pregnancy outcome distribution, prenatal diagnosis rates, and subsequent elective terminations rates vary by type of autosomal abnormality. Teratology 66:S7,S11, 2002. © 2002 Wiley-Liss, Inc. [source] | ||||||||||