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Biomedical subjects

F A Van Assche

Publications and source records attributed to F A Van Assche.

At least 73 records · Page 4Linked to original sources
PubMed1995

Identification of 'renin'-containing cells in the choriodecidua.

Chorionic trophoblast, decidual cells, and macrophages have all been named as the site of renin in the placental membranes. To establish more clearly the nature of the renin-containing cells in the placental membranes, double immunostaining techniques were used to stain renin and specific cell markers in the same tissue sections. Cytokeratin was selected as an ectodermal cell marker and CD68 as a cytoplasmic macrophage marker. Cross-binding between antibodies was prevented by blocking species-related binding sites between the first and second sequence of the double-immunostaining procedures and by using highly selective immunostaining techniques in the second sequence. The results clearly show renin immunostaining in CD68-positive macrophages and not in cytokeratin-positive trophoblast. The anti-renal renin monoclonal antibody showed high affinity cross-reactivity with cathepsin D, another aspartic proteinase that can release angiotensin I from angiotensinogen. This should be seen in the context of earlier findings that only two of four anti-renal renin monoclonal antibodies showed staining in uterine and placental tissues and both cross-reacted with cathepsin D. The results indicate that differentiation between renin and cathepsin D and, possibly, other substances with shared properties and epitope homology deserves more attention than it has received thus far.

Chorion↗
PubMed1995

Individual coping style and psychological attitudes during pregnancy and predict depression levels during pregnancy and during postpartum.

Fifty primigravidae were investigated from 30 weeks of gestation until 6 months after delivery to assess the predictive value of individual coping style, conception time and specific psychological changes during pregnancy for the depression levels assessed during the third trimester of pregnancy and 5 days, 6 weeks and 6 months after delivery. The individual coping style is an effective predictor of depression levels during the third trimester of pregnancy and 6 months after delivery, but not for the depression levels 5 days and 6 weeks after delivery. A path analysis revealed that high depressive coping and low social support-seeking predict a longer conception time, which all predict a more important lack of spousal support during pregnancy. Higher depressive coping, a longer conception time and a more important lack of spousal support during pregnancy all predict high depression levels 6 months after delivery. The present findings thus suggest helpful predictors for the psychological adaptation during the transition to parenthood.

Adaptation, Psychological↗
PubMed1995

Tobacco smoking impairs the local immunosurveillance in the uterine cervix. An immunohistochemical study.

Previous reports have supported an association between tobacco smoking and cervical neoplasia. Our observations show an association between smoking and a reduction of the numerical densities of Langerhans cells and of helper/inducer T lymphocytes in the squamous epithelia of the transformation zone of the uterine cervix. This suggests a local impairment of cell-mediated immunity by smoking. This immunosuppressive effect could support the concept that smoking is an independent risk factor for cervical neoplasia.

Adult↗
PubMed1995

Tobacco smoking and the uterine cervix: cotinine in blood, urine and cervical fluid.

Cotinine levels in blood, urine and cervical fluid of smokers and nonsmokers were analyzed by capillary-column gas chromatography. The sensitivity of this method appeared to be 100%. The specificity was lower (87.5% in blood, 25% in urine and 75% in cervical fluid). Nonsmokers exposed to smoke by others had low but detectable cotinine levels in the three body fluids. The highest cotinine levels in cervical fluid were detected during the proliferative phase of the cycle. Cotinine levels in cervical fluid and blood correlated well, but the correlation was less during the proliferation phase. Cotinine measurement in cervical fluid proves to be a reliable method to quantify exposure to tobacco smoke, even when induced by others.

Adult↗
PubMed1995

Coping style and preterm labor.

Psychometric tests (State-Trait Anxiety Index and Utrechtse Coping Lijst) were administered to 23 primigravidae hospitalized for preterm labor and to 22 controls in order to investigate whether women with and without preterm labor present a different coping style or (in) effectiveness of this coping and whether the coping style predicts duration of hospitalization and gestational age at delivery. No significant differences in trait anxiety nor in coping style were found between women with and women without preterm labor. However, within the group of women with preterm labor, coping mechanisms are important predictors of course and outcome of the preterm contractions. Palliative coping and social support seeking are protective mechanisms while active coping has an adverse effect upon outcome: an older gestational age at the moment of delivery is for 44% predicted by a higher social support seeking and a lower active coping.

Adaptation, Psychological↗
PubMed1994

The endocrine pancreas in nonimmune hydrops fetalis.

OBJECTIVE: Our purpose was to compare the endocrine pancreas of hydropic infants of immune and nonimmune origin. STUDY DESIGN: A quantitative morphologic study was performed on the pancreas in 10 infants with immune and nonimmune hydrops. The volume density of the endocrine pancreas in the gland was calculated, as was the numerical density of the endocrine cells in the islets. The percentage of the different cell types was measured on immunohistochemical stained slides. Ten normal infants were used as controls. RESULTS: An increased amount of endocrine tissue and an increased total number of islet cells of immune and nonimmune origin is present in hydropic infants. However, an increased proportion of the insulin-producing B cells is not present. CONCLUSIONS: The endocrine pancreas in hydrops fetalis of immune and nonimmune origin is equal, excluding hemolysis as the stimulating factor for equilibrated islet overgrowth. Metabolic stimuli, as seen in infants of diabetic mothers, are probably not involved, because they preferentially stimulate the insulin-producing B cells.

Case-Control Studies↗
PubMed1994

1,25-Dihydroxyvitamin D3 and osteocalcin in maternal and fetal guinea pigs.

Maternal and fetal 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and osteocalcin were measured in guinea pigs, to examine their potential use as animal models for fetal bone development and calcium homeostasis. Measurements were performed on days 42, 57 and 63 of gestation. Maternal serum total 1,25(OH)2D3 concentrations were increased only at the end of gestation (day 63). However, because the vitamin D binding protein (DBP) and albumin levels were decreased by 35-50% from day 42 onwards, the unbound 1,25(OH)2D3, calculated as the 1,25(OH)2D3/DBP molar ratio, was increased before day 63. Osteocalcin concentrations during gestation were 50-54% of levels found in nongravid animals. Fetal serum total 1,25(OH)2D3 concentrations were 20% of those in maternal guinea pigs. Since DBP levels were only 9-15% of maternal levels, the unbound 1,25(OH)2D3 was consistently higher in fetuses, from day 42 onwards. There was a rise in total and unbound 1,25(OH)2D3 between days 57 and 63 of fetal life. Osteocalcin concentrations were higher in fetal than in adult guinea pigs, and reached peak values on day 57 (1023 micrograms/l, i.e. 4.2 times higher than in adult female guinea pigs). Fetuses of guinea pigs that had received a restricted food supply for 14 days (days 49-63) had normal 1,25(OH)2D3 concentrations, but decreased osteocalcin concentrations compared with normal fetuses. The data obtained in fetal guinea pigs are comparable with those found in human fetuses, and suggest that the guinea pig may be a suitable model for studies on fetal bone and mineral development.

Animals↗
PubMed1993

C-peptide, insulin-like growth factors I and II, and insulin-like growth factor binding protein-1 in umbilical cord serum: correlations with birth weight.

OBJECTIVE: Our purpose was to determine the correlation between birth weight and hormones or growth factors believed to be involved in fetal growth: insulin, insulin-like growth factors I and II, and insulin-like growth factor binding protein-1. STUDY DESIGN: Five hundred thirty-eight cord serum samples were analyzed for insulin-like growth factor-I, insulin-like growth factor-II, C-peptide, and insulin-like growth factor binding protein-1 by immunoassay. Samples included all gestational ages in the third trimester and a large range of birth weights. RESULTS: Cord serum insulin-like growth factor-I concentrations increased until 39 weeks (+84% from 28 to 29 weeks), followed by a 21% decline at 41 weeks. Insulin-like growth factor-I levels were decreased by 40% in small-for-gestational-age (< 10th percentile) newborns and were increased by 28% in large-for-gestational-age (> 90th percentile) newborns in the absence of diabetes. Insulin-like growth factor-I levels were best correlated with birth weight (R = 0.48, p < 0.001). Cord serum insulin-like growth factor-II concentrations were sixfold to tenfold higher than those of insulin-like growth factor-I and were 8% to 10% (p < 0.001) higher in large-for-gestational-age than in average-weight and small-for-gestational-age newborns. Cord serum C-peptide concentrations were 28% and 34% higher in large-for-gestational-age than in average-for-gestational-age and small-for-gestational-age newborns, respectively. Insulin-like growth factor binding protein-1 levels were increased in preterm average-for-gestational-age and in term small-for-gestational-age newborns compared with term average-for-gestational-age newborns and showed a negative correlation with birth weight (R = -0.43, n = 131, p < 0.001). Insulin-like growth factor binding protein-1 was not correlated with C-peptide concentrations. CONCLUSIONS: Insulin-like growth factors I and II and insulin are all related to fetal growth and weight gain, and insulin-like growth factor-I correlates best with birth weight. Insulin is mainly related to fetal overgrowth (macrosomia). Insulin-like growth factor binding protein-1 may be a growth inhibitor in the fetus.

Adult↗
PubMed1993

Increased thromboxane formation in diabetic pregnancy as a possible contributor to preeclampsia.

OBJECTIVE: Because pregnant women with diabetes have an increased risk of preeclampsia, we tested the hypothesis that urinary excretion of thromboxane metabolites is increased in diabetic pregnancies without evidence of preeclampsia at the time of testing. STUDY DESIGN: Urinary excretion of thromboxane A2 metabolites (either 2,3-dinor-thromboxane B2 or 11-dehydro-thromboxane B2) was measured in 24 type I pregnant diabetic individuals and in 20 women with normal pregnancies between 28 and 32 weeks' gestation. RESULTS: The amount of 2,3-dinor-thromboxane B2 and 11-dehydro-thromboxane B2 in the urine of pregnant women with diabetes (1727 +/- 415 and 827 +/- 276 pg/mg creatinine) was significantly higher than in women with normal pregnancies (638 +/- 218 and 178 +/- 145 pg/mg creatinine) (p < 0.002 and p < 0.001). CONCLUSION: Our findings support a role for thromboxane in the pathogenesis of preeclampsia.

Diabetes Mellitus, Type 1↗
PubMed1993

The association of gonorrhoea and syphilis with premature birth and low birthweight.

OBJECTIVE: Provide evidence from prospective data that Neisseria gonorrhoeae may be an important cause of premature delivery and low birth weight in areas with high prevalence of genital infections. SETTING: Department of Obstetrics and Gynaecology, Kalafong University Hospital, Pretoria, South Africa in collaboration with the Departments of Microbiology and of Gynaecology and Obstetrics, Katholieke Universiteit, Leuven, Belgium. SUBJECTS: Two hundred and fifty six consecutive black pregnant women were examined during the first antenatal visit, and one to four weeks later a second culture for N gonorrhoeae was taken at random in 67 of them. Hundred and sixty seven were analysable, 75 were lost to follow up. METHODS: After obtaining detailed clinical history, an endocervical specimen for N gonorrhoeae culture (Thayer-Martin) and C trachomatis antigen detection (Chlamydiazyme (R)) was taken. Syphilis was diagnosed when both reactive plasma protein (RPR) and T pallidum haemagglutination inhibition assay (TPHA) were positive. Prematurity was defined as delivery at less than 37 gestational weeks. RESULTS: Infection with N gonorrhoeae (n = 9) and untreated syphilis (n = 7) were both associated with prematurity and low birth weight. After multi-variate regression analysis, age-adjusted parity, late sexual debut, number of recent sexual partners, infection with N gonorrhoeae and infection with syphilis revealed significant associations with low birth weight. However, infection with C trachomatis, presence of abundant vaginal discharge, social class, Trichomonas vaginalis infection, gestational weeks at first antenatal visit and number of previous miscarriages did not reveal such an association. Attributable risk of untreated gonorrhoea for premature birth was 72% and routine cultures were cost-benefit efficient. CONCLUSIONS: At least in countries where the prevalence is high, genital infections as well as the risk factors for acquiring them (young age, late sexual debut, number of recent partners) play a major role in the aetiogenesis of prematurity and low birth weight. N. gonorrhoeae is a main contributor, and in high prevalence areas it should be routinely looked for and treated for during pregnancy.

Adolescent↗
PubMed1993

In vivo glucose utilization by individual tissues in virgin and pregnant offspring of severely diabetic rats.

Adult offspring of diabetic rats or SDF rats are characterized by insulin resistance in the liver and extrahepatic tissues; this insulin resistance does not worsen during pregnancy. In this study, we determined the glucose metabolic index in tissues of anesthetized virgin and pregnant control and SDF rats in basal conditions and during a euglycemic hyperinsulinemic clamp. Tissues comprised insulin-sensitive tissues (five skeletal muscles, diaphragm, and periovarian white adipose tissue) and control tissues (duodenum and cerebrum). In addition, this study measured the GMI of placenta and fetuses. In basal conditions, SDF rats showed a slight decrease (9-29%) in the GMI of skeletal muscles compared with control rats; it was not altered by pregnancy in any of the tissues. During physiological hyperinsulinemia, virgin SDF rats exhibited a 25-70% decrease in the GMI of skeletal muscles compared with control rats; this decrease was not observed in diaphragm, or in adipose tissue in which the GMI was found to be increased. During pregnancy, SDF rats did not show an additional drop in the GMI of skeletal muscles, whereas the GMI of both skeletal muscles and adipose tissue was clearly diminished (25-60%) in control rats. The GMI of skeletal muscles was therefore comparable in pregnant control rats and SDF rats. The placental, but not fetal, GMI was increased by 24% during hyperinsulinemia in control rats; the placental and fetal GMIs, in basal and hyperinsulinemic conditions, were similar in control rats and SDF rats. In conclusion, skeletal muscles, but not white adipose tissue, are involved in the peripheral insulin resistance of the SDF rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1993

[Perinatology. Fetal origin of diseases in adults].

Perinatal medicine is mostly interested in the normal development of the growing fetus. Perinatal care is becoming even more important, since a disorder in fetal development, due to an abnormal intrauterine milieu, results in problems during infancy and adult age. There is clear evidence that this is the case in diabetes and pregnancy and in intrauterine growth retardation.

Adult↗
PubMed1992

Islet transplantation in diabetic pregnant rats normalizes glucose homeostasis in their offspring.

Diabetes of the mother during pregnancy induces alterations in the fetus, resulting in impaired glucose homeostasis in the offspring. In youngsters of severely diabetic mothers, during glucose infusion, hyperinsulinemia is associated with hyperresponsiveness of the beta-cells and insulin resistance. In order to normalize maternal metabolism, isolated islets from neonatal rats were transplanted into the vena porta of severely hyperglycemic (Streptozotocin) rats at day 15 of gestation. Strict glycemic control of the mothers was achieved throughout further gestation and lactation. In the adult offspring of these transplanted rats insulin levels during glucose infusion were significantly lower than in the offspring of sham-transplanted diabetic mothers and were not different from controls. The work confirms that the diabetic state of the mother during late gestation (the period of development of the endocrine pancreas and of the insulin-receptor system) is the inducing factor for the abnormal glucose homeostasis in the offspring, and normalisation of the hyperglycemia eliminates these long-term consequences.

Analysis of Variance↗