摘要:

Fertile life of oocytes is usually considered to be related to ovulation time. In the present study, fertile life of rat oocytes was studied in relation to resumption of meiosis. In pro-oestrus, meiotic resumption without concomitant ovulation was induced in most graafian follicles by injection of a small amount of LH or FSH followed by Nembutal. These follicles either ovulated or developed into luteinized unruptured follicles if Ovalyse (a GnRH analogue) was given 8 h after LH or FSH. In subsequent experiments, rats were injected with FSH or saline, and Nembutal; 4 or 8 h later, Ovalyse was given to induce ovulation; the rats were mated 14 h after Ovalyse. At day 20 of pregnancy, fetal survival was 30% in rats with meiosis advanced by 8 h, against 91 % and 70% in rats advanced by 0 or 4 h, respectively. Mortality occurred mainly during pre-implantation and early post-implantation. Advanced resumption of meiosis may cause pre-ovulatory ageing of oocytes; consequently, viability of these oocytes after ovulation is reduced.

ISSN:0378-7346    

DOI:10.1159/000292611

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The study presented herein measured 17-hydroxyprogesterone (17-OHP) levels in women with ovarian failure who conceived by transfer of embryos which resulted from donor oocyte fertilization. A significant increase in 17-OHP during the first trimester was seen compared to baseline nonpregnant levels. The 17-OHP levels increased from a baseline average of 47.7 ± 9.7 ng/dl to a first-trimester average of 175.8 ± 80.6 ng/dl in the donor oocyte recipients vs. 63.0 ± 38.0 ng/dl baseline to 295.0 ± 83.9 ng/dl first-trimester in the control group. Initially these data may appear to contradict previous findings demonstrating a lack of 17-OHP secretion by the first-trimester placenta. However, by comparing the first-trimester progesterone (P) levels of normal pregnant women, and also measuring 17-OHP in patients with natural menopause and surgical menopause given exogenous P we concluded the following about the origin of first-trimester sera 17-OHP levels: hydroxylation of P to 17-OHP by the ovaries, some secretion by the first trimester placenta; and also increased adrenal conversion of P to 17-OHP. Contributing to the total serum 17-OHP level is the fact that there is cross-reactivity with P to 17-OHP.

ISSN:0378-7346    

DOI:10.1159/000292612

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

This prospective study was undertaken to evaluate age distribution of erythrocytes longitudinally throughout pregnancy. Serial estimates of density distribution of cells (DDC), reticulocyte count, red cell distribution width (RDW), and mean corpuscular volume (MCV) in a group of healthy pregnant women at 12, 16, 20, 24, 28, 32 and 36 weeks gestation and during the latent phase of labor (39.04 ± 1.5 weeks). MCV increased constantly during pregnancy; however, the increase was not statistically significant. The mean reticulocyte percentage rose significantly at the 28th week, thereafter it remained at high levels until delivery. RDW increased significantly at the 20th week, remained at high levels until the 32nd week and thereafter declined towards the delivery. The cumulative DDC curve gradually shifted to the right during pregnancy, indicating a less dense cell population as the pregnancy progressed. In conclusion, a continuous alteration in age distribution of erythrocytes towards a younger cell population takes place from early pregnancy until the delivery of the fetus.

ISSN:0378-7346    

DOI:10.1159/000292613

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Maternal peripheral venous plasma interleukin 6 (IL-6) concentrations were determined during human pregnancy and labour at term and preterm. During preterm labour, IL-6 concentrations were significantly elevated (p < 0.02) compared to gestationally matched, non-labouring controls (53.7 ± 15.7 pg/ml, n = 17, and 15.4 ± 6.4 pg/ml, n = 23, respectively). IL-6 concentrations did not vary significantly during normal pregnancy and labour at term. These data support a role for IL-6 in the pathogenesis of human preterm labour, are evidence for the contention that preterm labour is mechanistically distinct at a biochemical level from normal labour at term and identify maternal peripheral venous plasma IL-6 as a biochemical marker of this condition.

ISSN:0378-7346    

DOI:10.1159/000292614

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

The effect of serotonin (5-HT) on the contractile activity of venous chorionic rings from normal and preeclamptic gestants was analyzed. The results indicate that the resting tension did not differ between the groups, but the spontaneous rhythmic contractions began earlier and were of higher amplitude in the preeclamptic group. Dose-response data indicate that venous segments from preeclamptic patients developed a 1.7-fold increase in sensitivity to 5-HT. These effects were accompanied by an increase in maximal isometric tension (Emax) and relaxation times. Decreased desensitization and lack of tachyphylaxis was observed in most of the vascular preparations from the preeclamptic group. These data suggest that 5-HT may have a role in the modulation of preeclampsia.

ISSN:0378-7346    

DOI:10.1159/000292615

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Seventeen pregnancies with pregnancy-induced hypertension (PIH) and 28 control pregnancies were analyzed with regard to maternal and fetal blood antioxidants and lipid peroxidation products (conjugated dienes). In PIH, maternal blood levels of conjugated dienes were higher than in normal pregnancy. Also the activities of platelet and plasma glutathione peroxidase (GSHPx) were higher in PIH. In umbilical cord blood, the appearance of conjugated dienes, the concentration of vitamin E and the activity of erythrocyte GSHPx were lower than the corresponding maternal values. There was no difference between PIH and normal pregnancy in the appearance of conjugated dienes in cord blood, but erythrocyte GSHPx and plasma vitamin A were lower in PIH. Cord blood plasma vitamin A showed a negative correlation to maternal mean arterial pressure. We suggest that lipid peroxidation is involved in the pathogenesis of maternal PIH, and it may also have effects on the vascular function and antioxidant status of the fetus.

ISSN:0378-7346    

DOI:10.1159/000292616

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Flow cytometric measurements of DNA using paraffin-embedded retrospective material were performed on 42 samples of ectopic conceptuses to see whether there were any aberrations from normal DNA. It was found that DNA aneuploidy was associated with tubal implantation in 14 (33%) cases. The range of DNA indices of the DNA aneuploid peaks was from 1.14 to 2.17. Near-diploid karyotype changes were seen in 8 (19%) cases. Six cases were found to be tetraploid. In 18 abortions with known cytogenetic status, all 3 cytogenetically normal cases showed DNA diploidy in flow cytometry. It was also found that 3 out of 10 cases of trisomy 21 were DNA aneuploid. Flow cytometric DNA reflects only chromosomal changes where a significant number of cells have either lost or acquired several chromosomes. DNA aneuploidy of ectopic pregnancies suggests a grave chromosomal aberration in one third of the cases. Abnormal embryogenesis may contribute significantly to the occurrence of ectopic implantation.

ISSN:0378-7346    

DOI:10.1159/000292617

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

An evaluation of the age distribution of erythrocytes in twin gestation was performed. Based on previous studies on age distribution of erythrocytes in late pregnancy, we have proposed that a more pronounced shift in age distribution of erythrocytes in twin pregnancy may be expected. We have used the density distribution of cells method for evaluation of age distribution of erythrocytes in women with twin pregnancies. Control curves for pregnant and nonpregnant women were obtained from our recently published studies. The cumulative density distribution of cells curve of erythrocytes of women with twin gestation was evidently shifted to the right as compared with the curve of erythrocytes of women with single gestation. The shift in age distribution of erythrocytes may suggest that erythrocytes in women with twin gestation have a shorter life span as compared to the life span of erythrocytes in women with singles. The age distribution shift of erythrocytes in women with twin gestation may be attributed to human placental lactogen augmentation of erythropoietm action.

ISSN:0378-7346    

DOI:10.1159/000292618

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

This in vitro study was undertaken to investigate the effects of endothelin 1 (ET-1) and endothelin 3 (ET-3) on intramyometrial arteries and myometrial tissue ofthe uterus from pregnant women at term. Segments of small myometrial arteries (outer diameter 100-500 µm) obtained at cesarean section were isolated and mounted in tissue chambers. The effect of ET-1 and ET-3 on isometric tension was compared with the action of noradrenaline. In similar experiments on myometrial strips, the effect of ET-1 and ET-3 was studied in comparison with oxytocin. ET-1 and ET-3 both produced contractions of arteries and myometrial strips, ET-1 being the most potent. The response of ET-1 was more powerful than the effect ofthe reference compounds, i.e. noradrenaline with regard to myometrial arteries and oxytocin with regard to the myometrium. It is concluded that endothelins are powerful constrictors of myometrial arteries from pregnant women and possess strong oxytocic effects. In particular, ET-1 could be involved in the regulation of myometrial contractility and/or uteroplacental blood flow

ISSN:0378-7346    

DOI:10.1159/000292619

出版商:S. Karger AG    

年代:1993

数据来源: Karger

摘要:

Laminin is a large noncollagenous glycoprotein localized in the trophoblast and glomerular basement membrane. We measured laminin levels in maternal serum, umbilical cord serum and amniotic fluid, both from preeclamptic and normal pregnant women, by enzyme immunoassay. The serum laminin levels in the preeclamptic group were significantly (p < 0.05 to p < 0.01) higher than those in the normal pregnant group. It has been suggested that laminin plays an important role in implantation of the placenta during early pregnancy. In this study, the amniotic-fluid laminin level at term was found to be lower than maternal serum laminin. We postulate that laminin may not have an important role in the maintenance of late pregnancy. There was a significant positive correlation between maternal serum laminin levels and serum uric acid levels. There was no significant correlation between maternal serum laminin level and blood pressure, urinary protein concentration, or any other laboratory data. These results suggest that there is damage of glomerular and placental spiral arteries in preeclampsia.

ISSN:0378-7346    

DOI:10.1159/000292620

出版商:S. Karger AG    

年代:1993

数据来源: Karger