Fetal and maternal lesions of cyanide dosing to pregnant goats

The present work evaluated the pathological effects in both dams and their fetuses of cyanide ingestion during pregnancy using goat as animal model. From the Day 24 of pregnancy, three pregnant goats were dosed by gavage with 3.0 mg KCN/kg bw/day, and two others received only tap water. All dams were euthanized and necropsied at Day 120 of pregnancy. The fetuses were examined carefully for gross abnormalities. Determinations of cyanide and thiocyanate were performed in maternal and fetal blood and in amniotic fluid. Samples of several organs were collected for histopathologic evaluation. No clinical changes were seen in any animal throughout the pregnancy. No malformations or dead fetuses were observed: however, placenta from one treated goat presented increased cotyledon surface area occupied by vascular lumina. Histological lesions in KCN-treated dams consisted of vacuolation of hepatocytes and thyroid follicular cells, increased number of vacuoles on thyroid follicular colloid. and spongiosis of cerebral, internal capsule, and cerebellar peduncles tracts. Fetuses from these mothers showed vacuolation of hepatocytes and thyroid follicular cells, and spheroids in the cerebellar white matter. Levels of cyanide and thiocyanate were higher in maternal than fetal blood, which suggests that these substances were largely but not freely transferred from mothers to fetuses. (C) 2009 Elsevier B.V. All rights reserved.

Estudo do peso e da idade gestacional de recem-nascidos e dos fatores que interferem no desenvolvimento fetal: nivel socio-economico, fatores maternos, fetais e placentarios

The present study was undertaken to determine the importance of socioeconomic factors (family income), urban or rural family location, parity, maternal age, the presence of maternal and fetal pathologies as well as placental abnormalities on the weight and gestational age of 566 newborns. The highest incidence of newborns with low birth weight for gestational age was significantly more frequent in urban populations when the mothers were from low socio-economic levels. In mothers from low socioeconomic levels infants with low birth weight for gestational age were seen in greater proportion among primaparas and had a tendency to be higher in mothers aged less than 20 years; prematurity was highest in mothers ≥ 30 years old and significantly higher from the 8th gestation on. Maternal and fetal pathologies emphasized these characteristics and placental pathologies were not correlated with the distribution of weight and length of gestation. In mothers of high socioeconomic levels age and parity were not correlated with weight and gestational age of the newborns.

New 12kW three-phase 18-pulse high power factor AC-DC converter with regulated output voltage for rectifier units

This work presents a new high power factor three-phase rectifier based on a Y-connected differential autotransformer with reduced kVA and 18-pulse input current followed by three DC-DC boost converters. The topology provides a regulated output voltage and natural three-phase input power factor correction. The lowest input current harmonic components are the 17th and the 19th. Three boost converters, with constant input currents and regulated parallel connected output voltages are used to process 4kW each one. Analytical results from Fourier analyses of winding currents and the vector diagram of winding voltages are presented. Simulation results to verify the proposed concept and experimental results are shown in the paper.