The activity of the von Willebrand factor cleaving protease ADAMTS-13 in newborn infants.

BACKGROUND: Unusually large von Willebrand factor (VWF) multimers have been observed in patients with thrombotic microangiopathies (TMA), and absence of the VWF cleaving protease ADAMTS-13 activity is considered to be involved in the etiology of TMA. Increased amounts of large multimers of VWF have also been identified in neonates. OBJECTIVE: We assessed ADAMTS-13 activity in healthy neonates, children and adults to establish baseline levels. PATIENTS AND METHODS: Cord blood was collected from 38 full-term newborns; venous samples were taken from 15 neonates on day 2-3 of life. Seventeen children, 24 healthy adults and seven patients with TMA were studied as well. ADAMTS-13 activity was quantified by the binding of the subjects' plasma VWF to collagen before and after enzyme activation. The multimer distribution of VWF was also determined. RESULTS: Neonates and children had percentage ADAMTS-13 activity similar to adults. However, two groups were apparent in the cord blood samples: while 28/38 newborns had percentage activity within the normal range of healthy adults (102 +/- 3.0%), 10 had significantly lower percentage activity (53 +/- 1.1%; P < 0.0001) that normalized by day 2-3. The VWF multimer distribution was the same in all cord blood samples and was not different compared with children and adults. High-molecular-weight VWF multimers were significantly increased in the 2-3-day-old neonates and in TMA patients. CONCLUSIONS: Although ADAMTS-13 activity was similar in neonates compared with adults, 26% of neonates had mildly reduced activity. Further studies are needed to investigate the complex interaction of VWF production and secretion with its size control by ADAMTS-13 in different age groups.

Alternative approaches to preterm labor.

Alternative approaches to the management of preterm labor have included home uterine activity monitoring, long-term tocolysis, bed rest, and intravenous hydration. Current evidence in the literature does not support improved pregnancy outcomes with these various therapies.

Prospective multicenter study of pregnancy outcomes in women with heart disease.

BACKGROUND: The maternal and neonatal risks associated with pregnancy in women with heart disease receiving comprehensive prenatal care have not been well defined. METHODS AND RESULTS: We prospectively enrolled 562 consecutive pregnant women with heart disease and determined the outcomes of 599 pregnancies not ending in miscarriage. Pulmonary edema, arrhythmia, stroke, or cardiac death complicated 13% of pregnancies. Prior cardiac events or arrhythmia, poor functional class or cyanosis, left heart obstruction, and left ventricular systolic dysfunction independently predicted maternal cardiac complications; the cardiac event rate can be predicted using a risk index incorporating these predictors. Neonatal complications (20% of pregnancies) were associated with poor functional class or cyanosis, left heart obstruction, anticoagulation, smoking, and multiple gestations. CONCLUSIONS: Pregnancy in women with heart disease is associated with significant cardiac and neonatal complications, despite state-of-the-art obstetric and cardiac care. Maternal cardiac risk can be predicted with the use of a risk index.

The effect of indomethacin tocolysis in preterm labour on perinatal outcome: a randomised placebo-controlled trial.

OBJECTIVE: To determine whether indomethacin tocolysis in preterm labour is associated with a better perinatal outcome than placebo. DESIGN: A randomised placebo-controlled trial. SETTING: Two university teaching hospitals with level three neonatal intensive care units. POPULATION: Women in preterm labour with intact membranes between 23 and 30 weeks of gestation. METHODS: Random allocation to tocolysis with indomethacin (50 mg followed by 25 mg 6 hourly for 48 hours) or placebo in a double-blind fashion. MAIN OUTCOME MEASURES: The primary outcome, perinatal mortality or severe neonatal morbidity, was defined as perinatal death, necrotising enterocolitis, bronchopulmonary dysplasia, intraventricular haemorrhage or peri-ventricular leucomalacia. Data were analysed using odds ratios (OR) and 95% confidence intervals (95% CI). RESULTS: Between March 1995 and February 1996, 34 women (39 babies) were recruited. The baseline characteristics of the two groups were similar. No patient was lost to follow up. In the indomethacin group, gestation was prolonged by > 48 hours in 13/16 (81%) of women vs 10/18 (56%) in the placebo group. The incidence of perinatal mortality or severe neonatal morbidity was not significantly different between the groups, but occurred in twice as many babies in the indomethacin group as in the placebo group--6/19 (32%) vs 3/20 (15%) OR (95% CI) 2.62 (0.44-18.8). There was one perinatal death, of a baby delivered at 24 weeks of gestation. This occurred in the indomethacin group. CONCLUSION: There is no evidence that indomethacin tocolysis is beneficial, and further trials are needed to assess the impact of indomethacin tocolysis in preterm labour.

Risk and predictors for pregnancy-related complications in women with heart disease.

BACKGROUND: The physiological changes of pregnancy can result in cardiovascular complications in the mother, which in turn may have fetal implications. Prior studies have focused on specific cardiac lesions or identified univariate predictors. There is a need to refine the risk stratification of women with heart disease so they can receive appropriate obstetrical counseling and care. METHODS AND RESULTS: We examined the outcomes of 221 women with heart disease who underwent 276 pregnancies and received their obstetrical care at three Toronto hospitals from 1986 through 1994. Those who underwent therapeutic abortions were excluded. Among the study participants, there were 24 miscarriages and 252 completed pregnancies (pregnancies not ending in miscarriage). Maternal heart failure, arrhythmia, or stroke occurred in 45 completed pregnancies (18%). There were no maternal deaths. Poor maternal functional class or cyanosis, myocardial dysfunction, left heart obstruction, prior arrhythmia, and prior cardiac events were predictive of maternal cardiac complications. These predictors were incorporated into a point score that can be used to estimate the probability of a cardiac complication in the mother. The rate of cardiac complications for a patient with 0, 1, and >1 of the above factors was 3%, 30%, and 66%, respectively. Neonatal complications occurred in 42 completed pregnancies (17%). Neonatal events included death (2), respiratory distress syndrome (16), intraventricular hemorrhage (2), premature birth (35), and small-for-gestational-age birth weight (14). Poor maternal functional class or cyanosis was predictive of neonatal events. CONCLUSIONS: Despite low maternal and neonatal mortality, pregnancy in women with heart disease is associated with significant cardiac and neonatal morbidity. The probability of maternal cardiac or neonatal events can be predicted from baseline characteristics of the mother.

Ovarian effects upon maternal glucose tolerance.

Ovaries from homozygous diabetic (db/db) female mice were removed and transplanted into the empty left ovarian sacs of normal homozygous (m/m) female mice which had undergone left oophorectomies. To produce controls, the previously removed normal left ovaries were transplanted into the empty left ovarian sacs of other normal (m/m) left oophorectomized females. Glucose tolerance tests were done on the study and control mice before surgery, after surgery, during pregnancy, and after delivery. There were no significant differences in the glucose tolerance test results between study group and controls before or after surgery. However, the study group, when compared to the controls, had a statistically significant glucose intolerance during pregnancy. After delivery, the glucose levels returned to normal. The ovaries from diabetic (db/db) female mice may produce hormones which, by themselves or in concert with the fetal and placental hormones, may produce maternal glucose intolerance during pregnancy.

Gestational diabetes diagnostic criteria: long-term maternal follow-up.

OBJECTIVE: The purpose of this study was to determine if the risk of having diabetes later in life was different in those who were gestational diabetic by Coustan criteria and not by National Diabetes Data Group criteria and those who are gestational diabetic only by National Diabetes Data Group criteria. STUDY DESIGN: Between 1988 and 1990, 331 patients from the Springfield area who were diagnosed as gestational diabetic by either criteria since 1975 were examined for the development of diabetes by history or by 2-hour, 75 gm glucose tolerance test. National Diabetes Data Group criteria were used to determine normality or diabetic abnormality. Variables associated with diabetes were obtained. The data were analyzed using three groups: (1) gestational diabetic by National Diabetes Data Group criteria, (2) gestational diabetic by Coustan's criteria only, and (3) both groups 1 and 2. RESULTS: Group 1 had 190 (57.4%) and group 2 had 141 patients (42.6%), of which 25.3% and 25.5% had diabetic abnormality, respectively. Variables predictive for the development of diabetic abnormality were glucose tolerance test fasting value, number of gestational diabetic pregnancies, time to follow-up, and prepregnancy weight index. There were no differences in these variables between the normal patients or those with diabetic abnormality in groups 1 and 2. CONCLUSION: Because Coustan criteria classify an additional 68.9% patients who have the same risk and risk factors for later development of diabetic abnormality and pregnancy complications compared with patients who are gestational diabetic by National Diabetes Data Group criteria, the criteria of Carpenter and Coustan should be adopted as the standard for diagnosing gestational diabetes.

Ultrastructural localization of filamentous actin within neuronal interphase nuclei in situ.

Previous biochemical studies utilizing isolated nuclei and nuclear matrices have shown actin to be a constituent of the interphase nucleus. In addition, recent ultrastructural work has shown the presence of actin and myosin within nuclei of interphase cells in situ. It was unclear, however, whether this intranuclear actin is present in the unpolymerized globular actin or the filamentous (F)-actin form. The present work, using confocal microscopy and ultrastructural cytochemical techniques, demonstrates the presence of F-actin within interphase nuclei of intact, uncompromised, dorsal root ganglion neurons in vitro and in vivo. Labeling by FITC-phalloidin detected the presence of intranuclear F-actin adjacent to the nucleolar periphery in a small fraction of cells in vitro, an observation confirmed by three-dimensional reconstruction. Ultrastructural analyses of cells exposed to heavy meromyosin (HMM), showed the presence of typical "arrowhead" complexes. The observation that these complexes were associated with nucleoli confirms that the intranuclear ligand detected by FITC-phalloidin indeed represents F-actin. Postembedding labeling with HMM conjugated to 20-nm colloidal gold (HMM-Au20) resulted in labeling similar to that obtained with HMM. However, HMM-Au20 was found to label a much larger fraction of cells, both in vitro and in vivo, than did FITC-phalloidin or HMM. This finding indicates that labeling with HMM-Au20 more accurately reflects the extent of actin polymerization in nuclei. Results from double labeling with HMM-Au20 and an antibody to alpha-sarcomeric actin confirmed that only a small amount of nuclear actin is in the F-form. Together, these results represent a first ultrastructural demonstration of the presence of F-actin in nuclei of neurons. While the role of nuclear F-actin has yet to be defined, the results suggest that F-actin may represent a component of the molecular motor responsible for the dynamic positioning of specific chromatin domains into the tissue-specific, nonrandom patterns observed in many cell types.

Effect of labor on lymphocyte subsets in full-term neonates.

PROBLEM: To determine the effect of labor on lymphocyte subsets in full-term neonates. METHOD OF STUDY: Cord blood obtained at delivery from full-term neonates, six born vaginally and six born by elective Cesarean section, was analyzed for lymphocyte subsets. Monoclonal antibodies, immunofluorescence, and flow cytometry were utilized to determine the lymphocyte phenotype frequencies in these neonates. These frequencies were compared by mode of delivery and to adult peripheral blood reference ranges using a two-tailed Student's t-test, P < 0.05. RESULTS: A profile of significantly elevated T (CD2, CD3) and helper cells (CD4) and depressed Natural Killer cells (CD16, CD56) is characteristic of term Cesarean section neonates. Significantly depressed frequency of T cells (CD2, CD3) and helper T cells (CD4) and elevated Natural Killer cells (CD16, CD56) is characteristic of vaginally delivered neonates. CONCLUSIONS: The mode of delivery affects the lymphocyte subset frequencies in full-term neonates.

The effect of minor degrees of glucose intolerance on the incidence of neonatal macrosomia.

The incidence of neonatal macrosomia in infants of mothers who have only one abnormal value in a 3-hour glucose tolerance test (GTT) is greater than normal. Often, corrections for gestational age have not been used in the analysis, and in the few studies in which corrections were made, the results conflicted. In this study, the birth weights of infants from 157 patients who had only one abnormal GTT value were compared with the birth weights of infants from normal mothers, with and without correction for gestational age. Analysis using three different GTT criteria revealed that the incidence of birth weight greater than 4000 g was 20% or greater in the infants of mothers who had only one abnormal GTT value and only 12.4% in controls. However, when adjusted for gestational age, there were no differences in the birth weights and percentage of large for gestational age (LGA) infants in the study groups versus controls. The mean and gestational age-adjusted birth weights of the greater-than-4000-g neonates born to women with one abnormal GTT value were no different than those of controls. However, at delivery, the gestational ages of patients with one abnormal GTT value tended to be slightly greater than those of controls by 0.1-0.6 weeks, suggesting that minor degrees of abnormal glucose metabolism may prolong pregnancy in some patients. When compared with the literature, the findings of this study suggest that the National Diabetes Data Group criteria may be too high as a screen for LGA infants.

Prevention of neonatal macrosomia in gestational diabetes by the use of intensive dietary therapy and home glucose monitoring.

This study was undertaken to determine if intensive dietary therapy, home blood glucose monitoring, and the selective use of insulin can be effective in preventing fetal macrosomia. All patients were screened at 24 to 28 weeks' gestation using a modification of O'Sullivan's criteria. The 153 patients diagnosed as gestational diabetics by the study protocol were placed on a 1800 to 2000 Kcal American Diabetes Association diet and taught home glucose monitoring. Insulin therapy was initiated only if blood glucose control was inadequate. There were no significant differences (p greater than 0.05) between the study and reference populations in regard to mean birthweight or the incidence of macrosomia. Since our study criteria for diagnosing gestational diabetes were slightly different from those of the National Diabetes Data Group (NDDG), data from 99 patients meeting the NDDG criteria were analyzed in a similar manner. No significant differences were found between this subgroup and the reference population. Since only 7.2% of our study patients required insulin, we conclude that the incidence of fetal macrosomia in gestational diabetes can be kept equal to that of the general population by a program of intensive dietary therapy and home glucose monitoring, with insulin being used only therapeutically, not prophylactically.

Effect of pregnancy on glucose metabolism in glucose intolerant 'BB' Wistar rats.

Little is known about the effect of pregnancy on the 'BB' Wistar rat, an animal model of insulin-dependent (type I) diabetes. The pathogenesis of diabetes in this animal model seems to result from antibody-mediated natural killer cell destruction of pancreatic beta cells. The glucose metabolism of glucose intolerant female rats (study group) was studied prior to pregnancy, during pregnancy, and postpartum using glucose tolerance tests (GTT). Control rats with normal GTT were studied and bred in a fashion similar to the study animals. Before becoming pregnant, the GTT levels of the chemically diabetic rats were significantly different from those of the controls (p less than 0.05). The GTT values of the study animals decreased during pregnancy to levels seen in pregnant controls. After pregnancy, the GTT values of the study animals returned to prepregnant levels. Based on these observations, it appears that pregnancy may block the autoimmune destruction of beta cells, causing an increase in insulin production and release, thereby improving glucose metabolism.

Diabetic pregnancy. The effect of genetic susceptibility for diabetes on fetal weight.

Since macrosomic infants of diabetic mothers tend to remain obese throughout their lives, and obesity and heredity are factors predisposing to Type II diabetes, it can be hypothesized that infants who are going to develop diabetes later in life are more likely to be macrosomic at birth than those who are not going to develop diabetes as adults. This hypothesis was tested, using the c57/KsJdb+/+m mouse animal model of gestational diabetes. This animal is frankly diabetic in the homozygous diabetic form. In the heterozygous form, it develops gestational diabetes, and in the homozygous normal form, it is normal. The pups of heterozygous males and females that were bred were weighed, classified by sex, and identified. At 4 weeks of age, the genetic makeup of the pups was determined. From 37 litters, 140 pups were born and raised to weaning age. Multiple regression analysis of the data revealed that the homozygous diabetic pups weighed most at birth; the heterozygous gestationally diabetic pups weighed less, and the homozygous normal pups weighed the least. All comparisons of these groups were statistically significant. Sex and interlitter variation also were found to be significant factors determining birthweight. Controlling for sex and interlitter variation did not change the significance of the effect of the genetic tendency for diabetes on birthweight. This study indicates that in Type II diabetes, neonatal macrosomia in part may be determined by the genetic or congenital susceptibility to develop diabetes in the future.

Increased mortality and aneuploidy in embryos from rabbits injected with Newcastle disease virus at the time of ovulation and conception.

In the rabbit, ovulation and conception occur during an 8-10 hour period immediately following mating ("reflex ovulation"). We report here that live Newcastle disease virus (NDV; an avian paramyxovirus) injected into rabbits immediately following mating resulted in a high frequency of embryo death at a wide range of developmental stages. When measured at midterm, a greater than threefold increase in embryo mortality was observed (24.7% vs. 6.8%). Aneuploidy of a small acrocentric chromosome was observed in three of 60 live midterm embryos recovered from NDV-injected does. No aneuploidy was observed in 52 live midterm embryos from control, saline-injected does. These observations suggest that the NDV-exposed rabbit can provide a useful model for the study of the teratological effects of virus exposure occurring at or about the time of meiosis, ovulation, and conception.

The effect of maternal smoke exposure on the ultrastructure of fetal peripheral blood vessels in the mouse.

Ultrastructural changes have been found in umbilical blood vessels, placental blood vessels, and peripheral blood vessels of human fetuses whose mothers smoked during pregnancy. This study was undertaken to determine if similar changes could be found in peripheral blood vessels of mice fetuses whose mothers were exposed to cigarette smoke during pregnancy. Breeding mice of the C57BL/KsJ strain were placed in a smoking box similar to that described by Younoszai and exposed to cigarette smoke intermittently. This produces carbon monoxide levels in the adult mice similar to that found in human adults smoking one pack of cigarettes per day. Similarly caged mice of the same strain were used as controls. The female mice were not removed from their cage from pre-conception time until after delivery. Upon delivery each pup was sacrificed via neck fracture and the entire pup was immersed in a solution of 2.5% glutaraldehyde in 0.1 M cacodylate buffer at pH 7.3. While still under solution, the rear leg muscles were dissected free, sliced, and immersed in the same preservative for four to five hours. They were then placed in fresh 2.5% glutaraldehyde mixture overnight. The tissues were post-fixed in osmium ferrocyanide and en-block stained with uranyl acetate in a graded series of alcohol. The tissues were infiltrated with and embedded in Spurr. Sections were taken via an ultramicrotome and post-stained with uranyl acetate and lead citrate. The sections were examined in a Philips 201 electron microscope at 60 KV. In the peripheral vessels of the fetuses from smoke-exposed mothers, endothelial blebbing (both surface-type and vacuole-type) was seen.(ABSTRACT TRUNCATED AT 250 WORDS)

A simple and efficient method for obtaining urine samples from rats.

A method for collection of urine from rats was developed that is simple, reliable, and efficient. A 5 ml. polystyrene beaker is placed over the urethra and the base of the tail is stimulated with the fingers of one hand. Depending on the quality and quantity of urine needed the perineal area may be shaved and the beaker may be held by hand or attached with tape.

Ultrastructural changes in neonatal sciatic nerve tissue: effects of passive maternal smoking.

The dangers of cigarette smoking having already been recognized, this study attempts to delineate findings from a passive smoking study at the ultrastructural level. The project utilized a model of mice subjected to cigarette smoke and encompassed the electron microscopic examination of neonatal tissue for morphological abnormalities. Study of sciatic nerve tissue taken from the offspring of passively smoked females revealed definite toxic effects on the neonatal tissue. This investigation, which concentrated on morphological changes, indicates that passive maternal smoke inhalation may result in abnormal changes to the fine structure of fetal tissue although further investigation in this area is necessary to broaden our knowledge and understanding of the mechanisms involved.

Localization and treatment of nonpalpable testes.

Five young males with bilateral nonpalpable testes are presented. In all instances, the testes were localized by laparoscopy. Only one patient had unilateral anorchia at laparotomy which was demonstrated by this technique. Laparoscopy may be more accurate than other nonoperative techniques for localizing nonpalpable testes. Additionally, it facilitates surgical planning and may obviate the need for surgical exploration in some patients.

Ultrastructural changes in neonatal liver tissue: effects of maternal drinking.

There is already sufficient evidence in the literature that alcohol abuse during pregnancy has a toxic effect upon the developing fetus; however, previous studies have not revealed any morphological changes in fetal or newborn liver specimens from animals exposed to alcohol in utero. As it is known that alcohol freely crosses the placental barrier, this investigation was an attempt to demonstrate that structural abnormalities can indeed be identified in neonatal mouse liver specimens from pups exposed to alcohol in utero. Chosen as a model for this study was the C57BL/KsJ mouse strain as this particular animal demonstrates an alcohol preference paralleling that of the human alcoholic. Findings appear to indicate the presence of abnormal changes on the morphological level in these study animals.