ISSN:0040-3709    

DOI:10.1002/tera.1420240216

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

ISSN:0040-3709    

DOI:10.1002/tera.1420240217

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractAdult pregnant Wistar rats were treated with phenytoin (100 mg/kg) orally from day 7 to 19 of pregnancy, and a control group was pair‐fed during the whole treatment period. Within 24 hours after parturition, the offspring were culled to six to eight per litter and reared by fostering or cross‐fostering. The physical and behavioral development of the offspring was observed up to 90 days of age. There was a reduced survival of the offspring and a reduction in body weight which persisted to the end of the experiment, though both of these effects could be reduced by cross‐fostering. Certain neurological defects were also seen in the prenatal phenytoin group. For example, there was a delay of up to 15 days in the development of the dynamic righting reflex, a decrease in ability of offspring to stay on a rotating rod, and a decrease in ability to walk along elevated parallel rods. There seemed also to be some loss of cliff avoidance. However, there was no change in the development of crawling and walking activities at 9–21 days of age, and no important changes were observed in a head dipping test or in a conditioned avoidance test at 26–34 days. There was a significant decrease in brain weight of the treated group at age 3 days which remained significantly lower than the controls even at 90 days, but no change in the brain/body weight ratio. There was no difference in cerebellar DN

ISSN:0040-3709    

DOI:10.1002/tera.1420240202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractFetal malformations may introduce complications of maternal pregnancy. A polyhydramnios represents one such complication during pregnancy. We want to report five abnormal pregnancies which were marked by acute polyhydramnios and/or premature labor due to an amniotic band syndrome associated with cerebral herniation in two cases, malignant oral teratoma in one case, bilateral cystic hygromas associated with generalized fetal hydrops in one case, and multiple internal malformations in one case, α1‐fetoprotein (AFP) values between the 25th and 34th week of gestation were elevated 3.5 to 44 times the normal median value. Since all fetuses showed severe malformations incompatible with life our observations indicate the necessity to determine AFP in cases of acute polyhydramnios independent of the week of gestation. Conversely, elevated AFP levels in amniotic fluid obtained during prenatal diagnosis in the 16th week of gestation may also suggest rare fetal malformations outlined abo

ISSN:0040-3709    

DOI:10.1002/tera.1420240203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractSKF‐525A (SKF), a well known inhibitor of P450function, and N‐methyl‐2‐thioimidazole (MMI), an antithyroid drug resembling ethylenethiourea, were tested at the respective dosages of 40 mg/kg ip and 200 mg/kg po, for their individual or combined effect on the teratogenicity of an oral dose of 60 mg/kg ethylenethiourea (ETU). All chemicals were dissolved in distilled water and administered to rats on the 13th day of pregnancy. MMI and ETU were dosed simultaneously, one hour after dosing with SKF. Control groups were given equivalent doses of ETU (positive control), SKF, MMI, or SKF + MMI. Term fetuses were evaluated for anomalies according to the established procedures. No teratogenic activity was attributed to treatments with SKF, or MMI, or their combination. However, in the remaining test groups, MMI + SKF + ETU, or SKF + ETU, the type, incidence, and intensity of anomalies, compared to the group given only ETU, were markedly increased and were similar to those previously reported to occur at 120 mg/kg or higher doses of ETU. Pretreatment with either 40, 60, or 80 mg/kg of sodium phenobarbital injected once or twice a day on days 9–12 of pregnancy, or 20 mg/kg/day of methylcholanthrene on days 11–13 of pregnancy, failed to alter significantly the teratogenicity of a subsequent dose of 60 mg/kg of ETU given orally on the 13th day o

ISSN:0040-3709    

DOI:10.1002/tera.1420240204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractRetinoic acid (RA) (78 mg/kg) administered to ICR mice on days 9.0, 9.5, and 10.0 of pregnancy (plug day = day 1), resulted in cardiac malformations in 37.6% of the surviving fetuses, including transposition of the great arteries, ventricular septal defects, and double outlet right ventricle. Histological examination of the hearts of embryos observed 24 hours after in vivo or in vitro exposure to RA on day 9 revealed abnormalities in endocardial cushion tissue. The volume of the atrioventricular endocardial cushions was reduced in treated embryos as was the ratio of the size of the cushions to the size of the heart. The endothelial layer of the atrioventricular endocardial cushions appeared to be unaffected by the retinoic acid, however, the mesenchymal cushion cells were significantly reduced in number when compared with controls. Labeling with [3H]‐thymidine indicated that the mitotic activity of the mesenchymal cell population was significantly decreased while that of the endothelial cells was comparable to control levels. The extracellular matrix or cardiac jelly of the endocardial cushions also appeared to be affected by RA exposure, as shown by studies utilizing colloidal iron to stain GAGs, which revealed a decrease in the amount of stainable material in treated cushions. Two possible causes for the reduced thymidine index of the cushion mesenchyme are discussed, namely, a direct effect of RA on the mesenchymal cells or an indirect effect via the altered extracellular matrix of the cushion tissu

ISSN:0040-3709    

DOI:10.1002/tera.1420240205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractAlthough cortisone treatment for induction of cleft palate in mice has been shown to delay the time of palatal shelf elevation, the effects of delayed elevation of shelf contact have not been critically evaluated in a cortisone‐sensitive mouse strain. The objective of this study was to evaluate palatal development in cortisone‐treated A/J mice in order to determine whether the shelves make contact upon elevation. Morphometric analysis of frozen sections revealed that cortisone‐treated shelves were smaller than control shelves with apparent reductions in both the content of extracellular matrix and the number of cells. At a light microscopic level, thinning of medial epithelium in cortisone‐treated palates appeared similar to that in untreated palates with spontaneous cleft lip and palate. Shelf elevation was delayed by approximately 12 hours and only half of the cortisone‐treated palates achieved complete horizontal positioning of the shelves in all regions of the palate. Immediately after elevation, all control palates had extensive vertical contact along the complete length of the palate. In contrast, approximately 20% of the cortisone‐treated fetuses had contact between the shelves in the middle palate region only, with the mean area of contact only 20% as large as in control fetuses. As a result, the net shelf contact in all the cortisone‐treated fetuses was only 4% of the potential contact shown in control fetuses. Therefore, failure of the palatal shelves to elevate and make extensive contact appeared to be the major factor contributing to cortisone‐induced cleft pal

ISSN:0040-3709    

DOI:10.1002/tera.1420240206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractPregnant Wistar rats were injected with hydroxyurea (HU) intraperitoneally (IP) at one of several 6‐hour intervals on days 9–10.75 to study the role of circadian growth variations in the teratologic response of the fetuses. Two stocks of rats were studied and the results in each compared. The fetal response to HU, as observed at day 21, was not detectably modified by circadian fetal growth variation. No correlations between hour of HU administration and fetal weight, placental weight, resorption, or total malformation rates were found. Cyclic variations in the incidence of hydronephrosis and left umbilical artery was observed, but it was not clear that these were related to maternal light:dark cycles. Differences of response between two stocks of rats included marked variation in the incidence and type of malformations and variations in the tuning of peak incidence for some but not all malformati

ISSN:0040-3709    

DOI:10.1002/tera.1420240207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractAn animal model system has been established which reproduces some of the features of the Fetal Hydantoin Syndrome. This pattern of altered growth and development includes growth retardation, craniofacial anomalies, distal phalangeal hypoplasia, and mental deficiency. Rats exposed in utero to phenytoin on gestational days 9, 11, and 13 exhibited fetal onset growth retardation, abnormalities of the craniofacial region and axial skeleton. In addition, the exposed offspring had significantly lower fetal weights, a shortened snout and a high‐arched, irregular palate, and significant delays in skeletal maturation. These abnormalities resemble those reported for the Fetal Hydantoin Syndrome and provide a means to study the effect of phenytoin on the morphological and biochemical development of the fetu

ISSN:0040-3709    

DOI:10.1002/tera.1420240208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractThe purpose of the research was to determine if pregnant rats subjected to a maximum tolerated duration of exposure to air at 6 atmospheres absolute pressure (ATA) (50.3 meters seawater) would have an increased frequency of fetal death, resorption, low birth‐weight, or malformations. Ninety pregnant rats were assigned to one of three exposure schedules during organogenesis: days 9–11, 12–14, or 15–17, and were randomized between one treatment and two control groups. The treatment group was subjected to 6 ATA for 70 minutes with compression and decompression at 1.8 ATA (18.3 meters seawater)/minute. Control groups were exposed to either 1 ATA of air (surface) within the hyperbaric chamber, or 1 ATA of air outside the chamber. For 30 minutes following decompression, chamber‐treated animals were placed in a slow, motor‐driven rotating cage, and assessed for gait disturbances from decompression sickness. On Day 20 of gestation, laparotomy was performed, and corpora lutea, implantations, and resorptions were counted. Fetuses were weighed, sexed, and examined for gross malformations. Subsequently, they were fixed, sectioned, and examined for visceral anomalies. Minor visceral anomalies and anatomical variations were present in 16.3% of all fetuses; however, no significant differences existed between groups. Similarly there were no significant differences when number of resorptions, number of dead fetuses, mean fetal weights, and malformations were compared by analysis of variance. Finally, there was no relation between symptoms of decompression sickness and any of the above measures. These results indicate that exposing rats to air at increased atmospheric pressure does not affect fetal health

ISSN:0040-3709    

DOI:10.1002/tera.1420240209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY