Differential effects of Notch ligands Delta-1 and Jagged-1 in human lymphoid differentiation.

Notch signaling is known to differentially affect the development of lymphoid B and T cell lineages, but it remains unclear whether such effects are specifically dependent on distinct Notch ligands. Using a cell coculture assay we observed that the Notch ligand Delta-1 completely inhibits the differentiation of human hematopoietic progenitors into the B cell lineage while promoting the emergence of cells with a phenotype of T cell/natural killer (NK) precursors. In contrast, Jagged-1 did not disturb either B or T cell/NK development. Furthermore, cells cultured in the presence of either Delta-1 or Jagged-1 can acquire a phenotype of NK cells, and Delta-1, but not Jagged-1, permits the emergence of a de novo cell population coexpressing CD4 and CD8. Our results thus indicate that distinct Notch ligands can mediate differential effects of Notch signaling and provide a useful system to further address cell-fate decision processes in lymphopoiesis.

Vesicouterine fistula after manual removal of placenta in a woman with previous cesarean section.

Vesicouterine fistula is one of the less common acquired urogenital fistula and a rare event in obstetrics. We report a case which occurred after a vaginal delivery followed by manual removal of placenta in a woman who had a previous cesarean section. The fistula was successfully repaired 5 weeks after delivery.

Bartter's syndrome and pregnancy.

Bartter's syndrome is a rare renal tubular disorder and few cases are reported associated with pregnancy. We describe a case of long standing disease with a good obstetric outcome in which the main concern was to maintain normal potassium serum levels.

Spontaneous ovarian hyperstimulation and primary hypothyroidism with a naturally conceived pregnancy.

BACKGROUND: Ovarian hyperstimulation syndrome, not related to ovulation induction, is rare. A MEDLINE search from 1987 to 1997 using the key words "spontaneous ovarian stimulation," "pregnancy," and "hypothyroidism" revealed only five cases: three associated with pregnancies and two with primary hypothyroidism. CASE: A 25-year-old white gravida 2, para 1, at 11-12 weeks' gestation presented with mild distension of a nontender abdomen, myxedematous facies, and large bilateral, multilobulated ovarian cysts. Conception had occurred spontaneously. Thyroid stimulating hormone was elevated, and free triiodothyronine and free thyroxine were low. Hypothyroidism, associated with spontaneous ovarian hyperstimulation syndrome, was diagnosed, and oral levothyroxine (0.10 mg/day) was started. With TSH still elevated at 21 weeks, levothyroxine was increased to 0.20 mg/day, and by 24 weeks, TSH and ovarian size were normal. Vaginal delivery of a 1120 g male infant occurred at 28 weeks. CONCLUSION: A case of naturally conceived pregnancy associated with spontaneous ovarian hyperstimulation and primary hypothyroidism is reported.

[Hypertension associated with pregnancy. Epidemiologic study of 311 consecutive cases]. / Hipertensão associada à gravidez. Estudo epidemiológico de 311 casos consecutivos.

The epidemiologic aspects of 311 consecutive cases of hypertension associated with pregnancy seen in the Department of Obstetrics and Gynecology, Hospital de Santa Maria/University of Lisbon Medical School between January 1st 1988 and December 31st 1992, are reviewed. Seventeen cases were multifetal pregnancies. Using the criteria proposed by the American College of Obstetricians and Gynecologists the cases were classified as follows: Mild preeclampsia, 64 cases (7 in twins); severe preeclampsia 50 cases (5 in twins); chronic hypertensive disease, 81 (1 in twins); chronic hypertension with superimposed preeclampsia, 16 (all singleton pregnancies); transient hypertension of pregnancy, 84 (4 in twins); unclassified hypertension, 16 cases of singleton pregnancies. No maternal deaths occurred. The most frequent maternal complications (eclampsia, HELLP syndrome, abruptio placentae and acute renal failure) were seen in preeclampsia (mild and severe forms). Only 2 significant maternal complications were observed in the cases of superimposed preeclampsia on chronic hypertensive disease. In the other groups maternal complications were seldom seen. Excepting in transient hypertension, perinatal morbidity and mortality were frequent in all groups, specially in severe preeclampsia and superimposed preeclampsia, when the delivery occurred before 34 weeks; after that time of pregnancy there were no neonatal deaths in any of the groups and intrauterine growth retardation and fetal distress were the most common fetal complications in all groups. In the whole, uncomplicated chronic hypertension and transient hypertension of pregnancy were the clinical situations in which maternal and perinatal complications were milder and less frequent. No perinatal problems were found in the group of unclassified hypertension.

[The clinical implications of the characteristics of uteroplacental flow in pregnancy complicated by hypertension]. / Implicações clínicas das características do fluxo útero-placentário na gravidez complicada por hipertensão.

The study of the relationship between maternal and perinatal outcome with uterine blood flows using a continuous wave Doppler unit, in hypertensive patients was the aim of our work. One hundred and thirty seven pregnant hypertensive women seen and delivered at the Department of Obstetrics, Santa Maria Hospital, Lisbon, were included in the study. Blood flows were classified as abnormal if and when the systolic/diastolic ratio was > 2.8 and/or a diastolic notch was seen in one or both uterine arteries. The cases were divided in 2 groups (normal/abnormal) according to the uterine blood flow and correlated with maternal and perinatal outcomes. Twenty-three of 26 maternal complications occurred in cases with abnormal uterine artery blood flow; we also found the large majority of perinatal complications within this group (100% perinatal deaths, 88% of the intrauterine growth retardation, 92% preterm deliveries, 93% fetuses with absent or reverted diastolic umbilical flow, 88% cardiotocographic patterns of fetal distress and 84% of the newborns admitted to the neonatal care unit). In conclusion, in pregnancies complicated by hypertension, uterine artery blood flow evaluation by continuous wave Doppler may identify a set of patients needing closer prenatal surveillance.

[The HELLP syndrome in pregnancy-related hypertension]. / Síndrome HELLP na hipertensão associada à gravidez.

During a 5-year period, 13 cases of HELLP syndrome were seen in hypertensive patients in the Obstetrics Department, Santa Maria Hospital, Lisbon. In 7 cases the syndrome occurred antepartum and in 6 during early early puerperium; gestational age and clinical features were very different from case to case. Four cases of eclampsia and 2 cases of acute renal failure occurred in 5 patients; there were 2 intrauterine deaths. Maternal mortality was nil. HELLP syndrome always implicates an important hepatic involvement with deleterious effects on the clinical status of the patients. Since the syndrome is often diagnosed in the puerperium and major complications seen in our study group occurred in that period, we conclude that all hypertensive patients must be closely monitored during the first 48 hours after delivery.

[Umbilical flowmetry in twin pregnancy. A method for identifying discordant fetal growth?]. / Fluxometria umbilical na gravidez gemelar. Um método de identificação de crescimento fetal discordante?

Umbilical artery velocimetry was performed in 33 twin gestations to evaluate the predictivity of the test (umbilical artery S/D difference between the pair > 0.4) in the screening of discordant fetal growth. Four out of 10 cases of discordant fetal growth were identified by the test and it was abnormal in 1 out of 23 concordant twins. The sensitivity was 40%, specificity 95%, positive predictive value 80% and negative predictive value of 79%. In spite of its low sensitivity the test can be useful in detecting discordant fetal growth in twin pregnancies.

[Relationship between the Steuart resistance index of the umbilical artery in non-pathologic pregnancy and the weight and ponderal index of the newborn]. / Relação entre o índice de resistência de Stuart na artéria umbilical na gravidez não patológica e o peso e índice ponderal do recém-nascido.

Umbilical artery Doppler velocimetry was performed at 28-32 and 36-38 weeks of gestation in a low risk population to correlate the Stuart's resistance index (Sistole/Diastole--S/D) to the weight and ponderal index of the newborn, and to determine the preditive value of S/D ratio greater than the 95 centil in the screening of newborns of weight or ponderal index lower than the 10 centil. Two hundred and eight two pregnant women were studied (146 at 28-32 weeks; 221 at 36-38 weeks) and Stuart Resistance Index was obtained by a continuous wave Doppler System. In both periods we had an inversely proportional correlation between the resistance index and the weight and ponderal index of the newborn; nevertheless the low sensibility and preditive value of the test shows that it should not be used as an isolated diagnostic tool to screen a low risk population for newborns with a low weight or low ponderal index.

[Doppler flowmetry of feto-maternal circulation: III --Absent and reverse diastolic flow in the umbilical artery]. / Fluxometria Doppler da circulação feto-materna: III--Ausência e inversão do fluxo diastólico na artéria umbilical.

Twelve cases of extreme umbilical blood flow impairement (8 cases with loss of end-diastolic blood flow and 4 cases with reversed flow) found among 658 pregnancies studied by continuous Doppler between April 1st 1989 and March 31st 1990, are reported. The findings were associated to intra-uterine growth retardation (92%), maternal hypertensive disease (50%) and perinatal death (33%); fetal Trisomy 21 was the sole problem in one of the cases with absent end-diastolic frequencies. Our results are discussed and compared to similar data reported recently. Clinical management is proposed, according to umbilical blood flow patterns, length of gestation and underlying clinical situations.

Acute effects of maternal cigarette smoking on fetal heart rate and fetal body movements felt by the mother.

Acute effects of maternal cigarette smoking on fetal heart rate (FHR) and fetal body movements felt by the mother (FM) were studied in 51 pregnant volunteers. Thirty four were chronic smokers (6 or more cigarettes per day, with an average of 14 cigarettes/day) and 17 were sporadic smokers (1 to 5 cigarettes per day, with an averaged of 3 cigarettes/day). In both groups the number of FM, fetal reactivity and short-term FHR variability decreased significantly in the 20 minutes following cigarette smoking; a sustained FHR rise of 10 or more beats/min was also found after the cigarette in more than 50% of the cases in the 2 groups. No statistically significant differences were found among the 2 groups when the post-cigarette data were compared. We conclude that maternal cigarette smoking produces important acute effects upon FM and FHR regardless the average daily number of cigarettes smoked by the mother.