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Biomedical subjects

F A Van Assche

Publications and source records attributed to F A Van Assche.

At least 91 records · Page 5Linked to original sources
PubMed1991

Do biphasic uterine contractions imply poor uterine function?

In a retrospective study of 362 cardiotocographic recordings of primigravidae in labour we found 8% biphasic or coupled uterine contractions. In augmented labour, biphasic contractions occurred almost twice as often as in spontaneous and induced labour. The duration of labour complicated with biphasic contractions was increased significantly in all types of labour. Therefore biphasic contractions may reflect uneffective uterine function. Contrary to other studies, the appearance of biphasic contractions showed no correlation with epidural analgesia and the incidence of instrumental deliveries or caesarean sections was not increased.

Analgesia, Epidural↗
PubMed1991

Intra-uterine Candida infection: a report of four infected fetusses from two mothers.

Although Candida albicans is a frequent inhabitant of the female genital tract, chorioamnionitis is rarely caused by this fungal organism. In this report we present two cases with manifest Candida chorioamnionitis. The first case is a twin pregnancy with premature delivery and survival of both twins. The second case is a pregnancy with intra-uterine contraceptive device in situ ending in a midtrimester abortion, followed by the next pregnancy also ending in an abortion in the second trimester. Possible triggers responsible for the increased invasiveness of otherwise benign Candida vaginitis are discussed. Foreign intra-uterine bodies such as contraceptive devices and cerclage sutures necessitate repetitive search for Candida species infection, and prompt adequate antifungal treatment in cases of documented infection. Both cases of the present report add further substantial evidence to the hypothesis of amniotic infection by ascending transcervical infection. The frequent concomitant cervical infections with other infectious agents as well as antibiotherapy influencing the normal Lactobacillary defence mechanisms are both likely to increase the risk. Systemic debilitating diseases that promote invasiveness are briefly discussed.

Adult↗
PubMed1991

Evidence for an insulin resistance in the adult offspring of pregnant streptozotocin-diabetic rats.

Our previous work has suggested the presence of an insulin resistance in the adult offspring of streptozotocin-diabetic pregnant rats. In this study we used the euglycaemic hyperinsulinaemic clamp technique with an isotope-dilution method to define and quantify this postulated insulin resistance in adult offspring of streptozotocin-diabetic rats. Under basal conditions, these rats had a lower body weight than control rats, but their glucose and insulin concentrations were normal. During the hyperinsulinaemic clamp, the steady-state glucose infusion rate was significantly lower in the offspring of streptozotocin-diabetic rats than in both age- and weight-matched controls, indicating insulin resistance. Basal peripheral tissue glucose utilization was normal in the offspring of streptozotocin-diabetic rats, but the dose-response curve was shifted to the right:insulin concentrations causing half-maximal stimulation of glucose utilization were increased by about 60% in the offspring of diabetic rats; the maximal stimulation of glucose utilization, however, was unaltered. Basal hepatic glucose production was normal, but again, half-maximal suppression of glucose production occurred at insulin concentrations 50% higher than in control rats; in addition, the maximal suppression of glucose production was significantly decreased, even at insulin concentrations of 5700 microU/ml. These data are evidence for an insulin resistance in the adult offspring of streptozotocin-diabetic rats, characterized by: (1) a decreased insulin sensitivity by peripheral glucose-utilizing tissues, and, (2) a decreased sensitivity and responsiveness of the liver.

Animals↗
PubMed1991

The effects of maternal diabetes on the offspring.

Diabetes in pregnancy has an influence on the development of the fetus. There are strong indications that the intrauterine diabetic milieu has long-lasting consequences. In the rat, mild diabetes during pregnancy induces decreased insulin secretion in later life, whereas severe diabetes is responsible for insulin resistance. In the human, data are available showing a long-term consequence in the offspring of type I diabetes and gestational diabetes mellitus.

Animals↗
PubMed1991

Measurement of individual plasma angiotensins in normal pregnancy and pregnancy-induced hypertension.

Individual angiotensin peptides were measured by a high pressure liquid chromatography-RIA (HPLC-RIA) technique in the plasma of 20 nonpregnant women, 17 women with normal pregnancy, and 49 with pregnancy-induced hypertension. Immunoreactive angiotensin-II (ANG-II) consisted mainly of ANG-(1-8) octapeptide (greater than 65%), variable proportions (15-25%) of ANG-(4-8) pentapeptide, and small to negligible proportions of ANG-(2-8) heptapeptide and ANG-(3-8) hexapeptide. Levels of ANG-(1-8) were significantly higher in women with normal pregnancy than in both nonpregnant women (P less than 0.0006) and women with pregnancy-induced hypertension (P less than 0.008); in the latter, levels were lower with increasing severity of disease. Levels of ANG-(4-8) were higher in women with normal pregnancy than in women with pregnancy-induced hypertension or nonpregnant women. When expressed as a proportion of ANG-(1-8) levels, however, ANG-(4-8) levels were not higher in normal pregnancy than in women with pregnancy-induced hypertension or nonpregnant women. It is concluded that the well known increase in ANG-II levels in normal pregnancy relates predominantly to the active ANG-(1-8) octapeptide and to a far lesser extent to the smaller ANG peptides. Similarly, lower ANG-II levels in pregnancy-induced hypertension relate predominantly to lower ANG-(1-8) levels.

Adult↗
PubMed1991

Absence of pregnancy-induced alterations in tissue insulin sensitivity in the offspring of diabetic rats.

We have previously demonstrated insulin resistance in the liver and peripheral tissues of the adult offspring of rats made diabetic with streptozotocin (SDF rats). In this study, a euglycaemic hyperinsulinaemic clamp was used to test the hypothesis that insulin resistance is further aggravated during pregnancy in SDF rats. Normal pregnancy was accompanied by a decrease in the sensitivity of the liver and peripheral tissues to insulin, with a normal responsiveness to insulin. In SDF rats no further decrease in the sensitivity of peripheral tissues to insulin occurred during pregnancy when compared with non-pregnant rats, and the dose-response curves of the glucose metabolic clearance rate during hyperinsulinaemia were similar in pregnant control and pregnant SDF rats. There was, however, a modest decrease in the sensitivity of the liver to insulin during pregnancy in SDF rats. The normal increase in plasma insulin levels during pregnancy was blunted in SDF rats: this resulted in increased glucose levels in maternal and fetal rats and increased fetal insulin concentrations, features compatible with mild 'gestation diabetes'. In conclusion, gestational diabetes develops in pregnant SDF rats, although there is no further deterioration in peripheral insulin resistance.

Animals↗
PubMed1991

Metabolic alterations in adulthood after intrauterine development in mothers with mild diabetes.

We studied the long-term effects of maternal diabetes mellitus on the offspring of experimentally induced diabetic Wistar rats. When stressed by an intravenous glucose load, the adult female offspring had impaired glucose tolerance and developed gestational diabetes mellitus when pregnant. Our results show that even mild diabetes mellitus induces an abnormal intrauterine milieu that causes morphological and functional changes in fetal development with consequences for later life.

Amino Acids↗
PubMed1991

Morphometric evaluation of B-cell function during glucose infusion in control and hyperresponsive rats.

According to their general appearance, the ultrastructural morphology of their organelles and their functional status, B cells can be divided into dark, unresponsive B cells with condensed mitochondria and narrow RER-cisternae, and pale activated B cells with orthodox mitochondria and distended RER. In control rats, during a three hour glucose infusion experiment, there is a shift from a majority of dark B cells to a majority of pale B cells, and a decrease in the proportion of dark and mixed islets in favour of the pale islets. No degranulation however (dark and light granules) occurs. In adult youngsters of severely diabetic mothers, known to be hyperresponsive to glucose stimulation, a more important mass of pale activated B cells is present in basal conditions, and is not augmented by stimulation. Dark and mixed islets are scarce in these animals and some degranulation occurs. The data illustrate that in control and in hyperresponsive rats, the B cells manage very well, to meet the increasing demand of insulin without any signs of exhaustion or damage. The data confirm in vivo, and at the morphological level, the concepts of functional heterogeneity and of dose-dependent recruitment of pancreatic B cells. Moreover functional heterogeneity of islets is suggested.

Animals↗
PubMed1991

Fetal and neonatal effects of treatment with angiotensin-converting enzyme inhibitors in pregnancy.

We conducted a systematic search of the world literature up to January 1, 1990 on the use of angiotensin-converting enzyme inhibitors for treatment of hypertension during pregnancy. A total of 25 publications reported 85 pregnancies in 81 women, including three twin pregnancies. Captopril had been used in 49, enalapril in 35, and both drugs in one of these pregnancies. The number of unbiased data are too limited to permit firm conclusions on teratogenicity, if any, of these agents. Contrary to earlier suggestions, we found no evidence that the use of these agents increases the likelihood of low weight for gestational age, respiratory distress syndrome, and/or persistent ductus arteriosus. Use of these agents in pregnancy can cause severe disturbance of fetal and neonatal renal function, such as oligohydramnios, pulmonary hypoplasia, and long-lasting neonatal anuria. Although the true incidence of these perinatal problems cannot be derived from the type of data hitherto available, there are strong suggestions that renal dysfunction is more common with the use of enalapril than with captopril. The frequency of serious perinatal complications is high enough to warrant extreme reluctance in prescribing angiotensin-converting enzyme inhibitors during pregnancy.

Abnormalities, Drug-Induced↗
PubMed1990

Anencephalics as organ donors.

Anencephalics can be divided into a large group without a functional hypothalamohypophysial system and a smaller group with a functional hypothalamohypophysial system. Anencephalics of the first group do not live more than a few hours, whereas the anencephalics of the second group can live up to 3 days. Those with a functional hypothalamohypophysial system have shown pain reaction. In anencephalics without a functional hypothalamohypophysial system, the endocrine pancreas does not reach full maturation and the use of these glands for islet transplantation can be questioned.

Anencephaly↗
PubMed1990

Glucose and insulin concentration in amniotic fluid and in maternal blood in early and in late pregnancy.

Glucose concentration in the amniotic fluid decreases towards the end of gestation, whereas the insulin concentration increases. The ratio between fetal (amniotic fluid) glucose to maternal glucose is reduced by about 50% at the end of pregnancy, whereas the ratio of C peptide is increased four times. The higher glucose concentration in amniotic fluid in early pregnancy could be explained by a lower fetal metabolic rate in the early stage of development and a low insulin activity of the fetus.

Adult↗
PubMed1990

Uterine norepinephrine levels are correlated with contraction force, but not with the occurrence of preeclampsia.

The aim of the present experiments was to investigate a possible correlation between the occurrence of preeclampsia and the levels of norepinephrine in human myometrial biopsies obtained from the lower uterine segment at the time of cesarean section. Norepinephrine was measured directly by the technique of muscle CATS, and indirectly by measuring the effect of their release on the K(+)-induced force development of the myometrial strip. Two distinct types of force development depending on the level of endogenous norepinephrine were observed, but they were not correlated with the development of preeclampsia. This was confirmed by the absence of correlation between uterine norepinephrine levels and the occurrence of preeclampsia. Therefore, no correlation between myometrial catecholamine content and the development of preeclampsia could be demonstrated.

Biopsy↗
PubMed1990

Osteocalcin is vitamin D-dependent during the perinatal period in the rat.

The vitamin D-dependence of renal calbindin D-28K and osteocalcin during the perinatal period was studied in fetuses (days 18 and 21) and neonates (days 2, 12, 17 and 22) of rats fed either a standard diet (0.85% Ca-0.7% P; "high Ca-P diet" rats) or a mildly Ca-P restricted diet (0.2% Ca-0.2% P; "low Ca-P diet" rats). Body weight and plasma calcium levels were identical in both groups. Plasma 1,25(OH)2D concentrations were markedly higher in the low Ca-P diet rats at all stages of fetal and neonatal life (in 22-day-old neonates: 536 +/- 58 pg/ml versus 126 +/- 12 pg/ml). 1,25(OH)2D concentrations increased between day 18 and 21 of fetal life, remained constant between day 21 of fetal and day 12 of neonatal life, and increased sharply between day 12 and 17 in both groups; after day 17, 1,25(OH)2D concentrations increased further in pups fed the low Ca-P diet. Renal calbindin D-28K reached peak concentrations on day 12 of neonatal life; calbindin D-28K levels were similar in the high and low Ca-P diet rats at all stages of perinatal development. Plasma osteocalcin levels increased steadily during the perinatal period; at most stages of perinatal life, and already from the fetal period was osteocalcin higher in the low Ca-P diet rats than in the high Ca-P diet rats (in 22-day-old pups: 1106 +/- 47 ng/ml versus 429 +/- 14 ng/ml). Femoral osteocalcin concentrations were also increased in fetal and early neonatal (days 2 and 12) low Ca-P diet rats, while the femoral calcium content and concentration of these rats were decreased in the late neonatal period (days 12, 17 and 22). These studies indicate that osteocalcin is vitamin D-dependent in the fetal and neonatal rat.

Animals↗
PubMed1990

[The role of prostacyclin and thromboxane in pregnancy].

During normal pregnancy vascular and hemodynamic changes are present. These alterations are due to a change in the balance between prostacyclin and thromboxane in favour of prostacyclin. In pregnancy induced hypertension the balance is in favour of thromboxane, explaining the absence of the vascular adaptation of pregnancy. Pharmacologic approach to restore the balance in favour of prostacyclin are promising.

Adult↗
PubMed1989

Severe systemic hypertension during pregnancy.

Severe hypertension during pregnancy remains an important cause of maternal mortality. Cerebral complications are frequently responsible for these deaths. Early detection of preeclampsia and preventive treatment are certainly goals for the future. In the management of severe pregnancy-induced hypertension, central issues are delivery and antihypertensive and anticonvulsive treatment. Cerebral disease consists mainly of bleeding and edema. Antihypertensive therapy can be dangerous and it is essential that hemodynamic control is provided.

Brain Diseases↗
PubMed1989

Maternal and fetal endocrine pancreas in the spontaneously diabetic BB rat.

The maternal and fetal endocrine pancreas were investigated in the diabetic BB rat on day 21 of pregnancy. The maternal pancreas of the diabetic rat contained practically no insulin-positive B cells. The A and D cell mass were also decreased, while plasma glucagon and somatostatin levels were normal or increased, confirming previous data. Six of 11 diabetic rats had B-cell-specific surface antibodies (ICSA), whereas only 1 of 10 nondiabetic rats was ICSA-positive. The volume density of insulin-positive cells was decreased in the fetal pancreas of diabetic BB rats compared to fetuses of nondiabetic rats, but the volume density of glucagon- and somatostatin-positive cells remained normal. The B cells of these fetuses were ultrastructurally less granulated and showed signs of increased cellular activity. Plasma insulin levels were decreased while plasma glucagon and somatostatin concentrations were normal. ICSA were not detected in fetuses of nondiabetic and diabetic rats. There were no differences in the histology of the spleen and thymus between both groups of fetuses. Metabolic characterization of the growth-retarded fetuses of diabetic rats revealed, besides lower plasma insulin concentrations, increased branched chain amino acid levels, and normal plasma Sm/IGF-I levels. The main conclusions from this study are: (1) Severe maternal diabetes decreases the pancreatic insulin-positive cell mass and plasma insulin levels in the fetus, but not the A and D cell mass and function; (2) ICSA are not detectable in fetal plasma; (3) the influence of maternal BB rat diabetes on fetal endocrine pancreas and metabolic environment resembles that of severe streptozotocin-induced diabetes.

Animals↗
PubMed1989

Plasma amino acids in diabetic pregnant rats and in their fetal and adult offspring.

Amino acid profiles and total amino-acid concentrations are established in nonfasting plasma of pregnant control, mildly diabetic and severely diabetic rats, and of their fetal and adult offspring. In pregnant rats at day 20 of gestation plasma amino acids can be regarded as normal in mildly diabetic mothers, but are significantly decreased in severely diabetic mothers. In fetuses of control rats, amino acid levels are twice as high as in the mother (fetomaternal ratio 2.0); in the fetuses of mildly diabetic mothers they are significantly lower than normal (fetomaternal ratio 1.3); in the fetuses of severely diabetic mothers they are also significantly lower than normal but with a normal fetomaternal ratio (fetomaternal ratio 2.0). In adult offspring of mildly diabetic mothers the concentration of almost all amino acids as well as that of total amino acid pool is significantly lower than in the controls; in the offspring of severely diabetic mothers they can be regarded as normal. No specific amino acid or group of amino acids can be held responsible for any of these changes, since all differences with control values display an overall effect, involving all or almost all amino acids.

Amino Acids↗