RESUMO
INTRODUCCIÓN: La aneuploidía más común entre los recién nacidos vivos es el síndrome de Down (SD). En estos niños el crecimiento está disminuido, con una frecuencia del 25% de restricción del crecimiento intrauterino, pero no se ha establecido el papel de la insuficiencia placentaria. El objetivo es estudiar la resistencia placentaria a través del Doppler de arteria umbilical con índice de pulsatilidad (IP) y el tiempo medio de desaceleración (t/2), y el posible efecto de la insuficiencia placentaria en fetos con SD. MÉTODO: Se realizó Doppler en la arteria umbilical en 78 fetos con SD, se midieron el IP y el t/2, y se compararon los resultados con los pesos de nacimiento. RESULTADOS: Se estudiaron 78 fetos con SD con 214 mediciones Doppler. El t/2 y el IP estaban alterados en el 71,5% y el 65% de las mediciones, respectivamente. La incidencia de t/2 alterado aumenta con la edad gestacional desde un 28,6% a las 15-20 semanas hasta un 89,3% sobre las 36 semanas (p < 0,01); cifras similares se observan para el IP. La clasificación de los pesos fue: 64% adecuados, 12% grandes y 24% pequeños para la edad gestacional. La última medición de t/2 antes del parto era normal en el 17% y estaba alterada en el 83%. En el caso del IP, los valores fueron normales en el 27% y anormales en el 73%. El peso de nacimiento, la edad gestacional y el porcentaje de niños adecuados para la edad gestacional eran significativamente mayores en el grupo con Doppler normal que en el grupo con Doppler alterado. El z-score del t/2 estaba marcadamente alterado (−2.23), pero el del peso de nacimiento solo estaba algo disminuido (−0,39). La mortalidad perinatal fue del 10%, significativamente mayor cuando el flujo diastólico era ausente o reverso. CONCLUSIONES: El estudio demuestra que los fetos con SD tienen una alta incidencia de alteración del Doppler umbilical para el IP y el t/2, lo cual sugiere una insuficiencia placentaria grave. Este deterioro parece iniciarse hacia el final del segundo trimestre y aumenta con la edad gestacional. Sin embargo, en estos fetos, la insuficiencia placentaria produce una ligera caída en el crecimiento fetal. Como hipótesis general pensamos que en los fetos con SD hay datos claros de insuficiencia placentaria, pero habría algún factor que les protegería de una restricción grave del crecimiento.
INTRODUCTION: The most common aneuploidy in live newborns is Down syndrome (DS), in these children growth is decreased, with a frequency of 25-36% of fetal growth restriction (FGR); however, it is not established the role of placental insufficiency. The objective is to study the Doppler of the umbilical artery with pulsatility index (PI) and half peak systolic velocity (hPSV) deceleration time and the possible role of placental insufficiency in fetuses with DS. METHOD: Doppler was performed in fetuses with DS, the umbilical artery and IP and hPSV were measured, and the results were compared with birth weights. RESULTS: 78 fetuses with DS were studied with 214 Doppler measurements. hPSV and the IP were altered in 71.5% and 65% of the measurements; the incidence of abnormal hPSV increases with gestational age from 28.6% between 15 to 20 weeks, to 89.3% over 36 weeks (p < 0.01), similar figures are observed with respect to the PI. The weight classification was: 24% of FGR, 12% of great for age and 64% of adequate for gestational age (AGA). The last measurement of hPSV before delivery was normal in 17% of the fetuses and was abnormal in 83%, in the case of PI the normal and abnormal values were 27 and 73%, respectively. Birth weight, gestational age, and the percentage of AGA children were significantly higher in the normal Doppler group than in the abnormal Doppler group. The hPSV z-score was markedly altered (−2.23), but the birth weight z-score is slightly decreased (−0.39). Perinatal mortality is 10% and is significantly higher when diastolic flow is absent or reverse. CONCLUSIONS: The study shows that DS fetuses have a high incidence of abnormal umbilical Doppler measured with IP and hPSV, which suggests severe placental insufficiency, this deterioration seems to start towards the end of the second trimester and increases with gestational age. However, in these fetuses, placental insufficiency causes a discrete drop in fetal growth. As a general hypothesis, we think that there is clear evidence of placental insufficiency in fetuses with DS, but there would be some factor that would protect these fetuses from severe growth restriction.
Assuntos
Humanos , Feminino , Gravidez , Artérias Umbilicais/diagnóstico por imagem , Síndrome de Down/diagnóstico por imagem , Insuficiência Placentária/etiologia , Velocidade do Fluxo Sanguíneo , Fluxo Pulsátil , Ultrassonografia Pré-Natal , Idade Gestacional , Ultrassonografia Doppler , Desaceleração , Retardo do Crescimento Fetal/etiologiaRESUMO
INTRODUCTION: Diastolic dysfunction may occur in fetuses with intrauterine growth restriction (IUGR) and may be assessed by myocardial tissue Doppler (MTD). We previously have shown that excursion index of the septum primum (EISP) is reduced in IUGR fetuses over 30 weeks because of a higher left atrial pressure. PATIENTS, SETTING, AND DESIGN: The sample was made up of 14 fetuses with IUGR. MTD examination was carried out with the sample volume placed at the basal lateral wall of the left ventricle (LV), interventricular septum (IVS), and free wall of the right ventricle (RV) to determine E'/A' ratios. EISP was calculated as the ratio between the maximal excursion of the septum primum into the left atrium during diastole and the maximal diastolic diameter of the left atrium. Mitral and tricuspid flows were assessed by the conventional Doppler method. OUTCOME MEASURES: Pearson's correlation test was used to analyze the correlations between the parameters. RESULTS: A positive correlation was observed between UARI and E'/A' ratios for RV (r = 0.63, P = .02), IVS (r = 0.59, P = .03), and LV (r = 0.41, P = .15). There was a negative correlation between EISP and IVS E'/A' ratios (r = -0.58, P = .03), and a positive correlation for LV (r = 0.49, P = .08). At the RV position, a weak negative correlation was observed (r = -0.32, P = .26). CONCLUSIONS: A higher left atrial pressure in fetuses with IUGR, indicated by the lower mobility of the septum primum, is accompanied by higher ratios between early and late diastolic myocardial velocities. Placental dysfunction was correlated to septal E'/A' ratios. Fetal MTD can be a useful method to assess severity of placental dysfunction and fetal distress.
Assuntos
Retardo do Crescimento Fetal , Septos Cardíacos/fisiopatologia , Contração Miocárdica , Insuficiência Placentária/etiologia , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda , Função do Átrio Esquerdo , Pressão Atrial , Estudos Transversais , Ecocardiografia Doppler , Feminino , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/fisiopatologia , Idade Gestacional , Septos Cardíacos/diagnóstico por imagem , Humanos , Insuficiência Placentária/diagnóstico por imagem , Insuficiência Placentária/fisiopatologia , Gravidez , Fatores de Tempo , Ultrassonografia Pré-Natal/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Pressão VentricularRESUMO
BACKGROUND: HIV patients with normal placental villi can suffer degenerative changes, the hormones that maintain pregnancy (HCG and progesterone) are diminishing, the pH of blood and oxygen tensions lower. OBJECTIVE: To demonstrate ultrastructural degenerative changes in placental villi at term of pregnant women infected by HIV-1 with zidovudine treatment. MATERIAL AND METHOD: Four placentas at term from seropositive mothers were analyzed; three specimens of each one were processed with conventional transmission electron microscopy. The results were compared with four control cases. RESULTS: Particles belonging to the viral structure associated with the microvilli of the syncytium and cytoplasmic regions were found. Were observed: interruptions of syncytial plasma membrane, syncytial edema; loss of ribosomes at level of RER, disappearance of mitochondria, Golgi complex, RER, lysosomes and cytoplasmic filaments, dissolution of hyaloplasmic matrix, filopodiums of syncytial membrane, aggregated nuclear heterochromatin and dilated perinuclear cistern. Macrophagues had numerous particles into cytoplasm, probably pertaining to electron dense material contained in the viral nucleocapsid, also observed in the stromal region close to the endothelium of the villus. Some myofibroblasts were detected suffering a process of cellular death with cariorexis event. CONCLUSIONS: These changes indicate that the cytopathic effect spreads from peripheral syncytium to stromal zone suggesting that the damaged placental barrier don't have the better conditions for the transmission of gases, nutrients and metabolites toward fetal circulation.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Vilosidades Coriônicas/ultraestrutura , Efeito Citopatogênico Viral , Infecções por HIV/patologia , HIV-1/ultraestrutura , Complicações Infecciosas na Gravidez/patologia , Inibidores da Transcriptase Reversa/uso terapêutico , Zidovudina/uso terapêutico , Adulto , Vilosidades Coriônicas/virologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Microscopia Eletrônica , Organelas/ultraestrutura , Insuficiência Placentária/etiologia , Insuficiência Placentária/patologia , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/virologia , Terceiro Trimestre da GravidezRESUMO
Este trabalho visa, através de revisão da literatura, enfatizar os efeitos adversos fetais e neonatais do uso de nicotina e de crack durante o pré-natal. Mostra as consequências comuns a estas substâncias tóxicas, tais como crescimento intra-uterino restrito, baixo peso ao nascimento, parto prematuro, abortamento espontâneo e malformações congênitas. Destaca-se também a síndrome da morte súbita do lactente e a síndrome do bebê crack, causadas pela nicotina e pelo crack, respectivamente.
This work seeks, through literature revision, to emphasize the fetal and neonatal adverse effects of the nicotine use and of crack during the prenatal. It shows the consequences common to these poisonous substances, such as: growth intrauterine restricted, low weight to the birth, premature birth, spontaneous abortion and congenital malformations. This work also stands out the syndrome of the sudden death of the infant and the syndrome baby crack, caused by the nicotine and for the crack, respectively.
Assuntos
Feminino , Gravidez , Recém-Nascido , Cocaína Crack , Cocaína Crack/efeitos adversos , Cocaína Crack/toxicidade , Complicações na Gravidez , Gravidez de Alto Risco , Tabagismo/efeitos adversos , Tabagismo/fisiopatologia , Feto/fisiopatologia , Hipóxia Fetal/etiologia , Recém-Nascido de Baixo Peso , Insuficiência Placentária/etiologia , Retardo do Crescimento Fetal/etiologia , Transtornos da Nutrição Fetal/etiologiaRESUMO
Endothelin-1 (ET-1), nitric oxide (NO) and prostaglandin E(2) (PGE(2)) are regulators of feto-placental hemodynamics. In this study we explore the inter-regulatory pathways that modulate the levels of these vasoactive agents in control and neonatal streptozotocin-induced (n-stz) diabetic rat placenta. ET-1 levels are increased in diabetic placenta when compared to controls (P<0.001), and are strongly reduced by an NO synthase inhibitor (P<0.001). PGE(2) production is increased in diabetic placenta when compared to controls (P<0.01), but these levels are not modulated by ET-1. NO levels, similar in control and in diabetic placenta, are not influenced by PGE(2), but they are negatively modulated by ET-1 in both control (P<0.05) and diabetic (P<0.01) placenta. We conclude that rat placental ET-1 inhibits NO levels but does not modify PGE(2) concentrations. The elevated levels of ET-1 and PGE(2) in diabetic placenta, potent vasoconstrictors of placental vasculature, are probably related to the induction of placental insufficiency and fetal hypoxia in this pathology.
Assuntos
Diabetes Mellitus Experimental/metabolismo , Dinoprostona/metabolismo , Endotelina-1/metabolismo , Óxido Nítrico/biossíntese , Placenta/metabolismo , Animais , Animais Recém-Nascidos , Diabetes Mellitus Experimental/fisiopatologia , Feminino , Hipóxia Fetal/etiologia , Hipóxia Fetal/fisiopatologia , Placenta/irrigação sanguínea , Insuficiência Placentária/etiologia , Insuficiência Placentária/fisiopatologia , Gravidez , Ratos , Ratos Wistar , Vasoconstrição/fisiologiaRESUMO
Se evaluaron 123 madres gestantes. Al ingreso la edad gestacional promedio fue de 24 semanas, el 24.4 por ciento sufria de desnutrición y un 51.9 por ciento del total de gestantes no llega a la ganancia óptima hacia el final de la gestación. Se observó que los niños de madres con desnutrición tenian un peso promedio de 2921 gr y los de madres sanas 3240 gr, la diferencia de 319 gr es estadisticamente significativa. Se recomienda que las madres que tienen un estandar de peso para la talla segun la edad gestacional menor o igual que 100 reciban una dieta suplementaria para llegar a un optimo de 120 para tratar de evitar la desnutrición tanto materna como del niño por nacer. Se encontro madres gestantes con obesidad en un 8.6 por ciento
Assuntos
Humanos , Feminino , Gravidez , Recém-Nascido , Insuficiência Placentária/etiologia , Gravidez , Distúrbios Nutricionais/epidemiologia , Altitude , Recém-Nascido de Baixo PesoRESUMO
Foram estudados os efeitos da administraçäo de hexaclorofeno durante a prenhez sobre prole de ratos; avaliou-se também a interaçäo de desnutriçäo intra-uterina com a exposiçäo à droga. A administraçäo de 10mg/kg/dia de hexaclorofeno na última semana de gestaçäo aumentou o número de nati-mortos e diminuiu o peso ao nascimento. Houve recuperaçäo do peso corporal quando os filhotes foram amamentados logo após o nascimento por ratas eutróficas e näo tratadas com hexaclorofeno. Essa recuperaçäo foi mais lenta para as fêmeas, quando comparadas aos machos. A desnutriçäo näo potencializou o efeito do hexaclorofeno. Näo foram observadas diferenças na vida adulta entre os grupos näo tratados e tratados com hexaclorofeno, quanto à avaliaçäo da emocionalidade e da aprendizagem no labirinto Hebb-Williams
Assuntos
Gravidez , Ratos , Animais , Masculino , Feminino , Insuficiência Placentária/etiologia , Peso ao Nascer/efeitos dos fármacos , Feto/efeitos dos fármacos , Hexaclorofeno/farmacologia , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Fatores Sexuais , Distribuição Aleatória , Ratos EndogâmicosAssuntos
Peso ao Nascer/efeitos dos fármacos , Feto/efeitos dos fármacos , Hexaclorofeno/farmacologia , Doenças Placentárias/etiologia , Insuficiência Placentária/etiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Comportamento Animal/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Feminino , Masculino , Gravidez , Distribuição Aleatória , Ratos , Ratos Endogâmicos , Fatores SexuaisRESUMO
A qualitative and quantitative microscopical examination of fetal stem vessels was performed in 50 placentas of stillborn infants and 50 normal controls. The vascular changes were morphologically similar in both groups, differences being only of quantitative nature. Subendothelial edema was more frequent in control placentas suggesting that it is not pathological. Subendothelial proliferation of smooth muscle cells prevailed in control and fresh stillbirths and could be due to arterial growth. Subendothelial proliferation of undifferentiated cells or fibrous and muscular tissues was more common in stillbirths. It occurred in most placentas of macerated stillbirths, but in fresh stillbirths the frequency was lower, though significantly higher than in controls. This thickening could represent the only reaction of placental vessels to fetal or maternal disease or cessation of fetal blood flow. Occlusion of the vascular lumen by fibrous and muscular tissues and vascular lumen divided by septa were present in the majority of the placentas of macerated stillbirths and rarely in fresh stillbirths, suggesting that in the macerated ones these changes were secondary to placental retention. The progressive collagenization of the media was the alteration most closely related to time of placental retention.
Assuntos
Endotélio Vascular/patologia , Morte Fetal/patologia , Placenta/irrigação sanguínea , Constrição Patológica/complicações , Endarterite/complicações , Feminino , Humanos , Músculo Liso Vascular/patologia , Placenta/patologia , Insuficiência Placentária/etiologia , GravidezRESUMO
The effect of maternal malnutrition on the energy metabolism of the developing rat placenta, related to fetal growth, was studied. Female virgin rats of the Wistar strain were fed restricted amounts of 25% casein diet, from puberty and throughout pregnancy. According to results, a significant decrease occurred in the activity of adenylate kinase, as well as a significant increase in the energy charge of the adenylate system (ATP, ADP), per gram of DNA of placental tissue near term, in the malnourished group. The data suggest that the significant increase of energy charge (ATP + 1/2 ADP:/ATP + ADP + AMP) of the placenta in the malnourished group, is the consequence of an inhibition of the reactions controlling ATP-consuming process, such as macromolecular synthesis pathways and active transport of substrates near term. This coincides with the simultaneous and significant decrease in fetal growth in this group.