摘要:

AbstractA male newborn infant, studied at autopsy, showed continuous splenogonadal fusion and severe peromelia associated with an unusual, possibly unique, cardiac malformation complex. The cardiac lesions included multiple right ventricular diverticula, tricuspid atresia, mitral to semilunar valve discontinuity, and absent muscular outflow tract septum. Tabulation of the time of appearance of relevant anatomic features in 351 normal human embryos of Carnegie stages 9 through 23 showed that the teratogenic influence in the present case probably occurred by stages 16–17. The nature and distribution of lesions observed suggest that proliferating undifferentiated mesenchme was the target of the unknown injur

ISSN:0040-3709    

DOI:10.1002/tera.1420250102

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

年代:1982

数据来源: WILEY

摘要:

AbstractAdult toxicity, embryo lethality, and teratogenicity of cytochalasins D and E (CD and CE) were determined for A/J, C57BL/6J, aeae, and OELN mouse strains. The adult LD50for CD (1.9–2.6 mg/kg) and CE (3.1–3.3) were similar for the strains. Although adult LD50s were similar, the embryo lethality and teratogenicity of CD and CE vary from strain to strain when all were treated with intraperitoneal injections on days 7–9 of gestation. CD was more teratogenic than CE and frequently produced exencephaly while CE did not. CD was more teratogenic in OELN and aeae(ED50± 0.7 mg/kg) than in A/J or C57BL/6J (ED50>1.2 mg/kg). OELN fetuses were more resistant to lethal effects of CD than the other strains which had fetal LD50s ± 1.2 mg/kg maternal weight. The F1fetuses of a cross of sensitive aeaeand resistant C57BL/6J showed intermediate sensitivity to exencephaly. The results suggest a genetic contribution to the response and differences in action of CD and CE as ter

ISSN:0040-3709    

DOI:10.1002/tera.1420250103

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe toxic and teratologic effects of caffeine on chick embryos ex‐planted at stages 4–7 and cultured for 19–22 hours were investigated. Caffeine, at 200–300 μg/ml, significantly increased the incidence of neural tube defects regardless of the developmental stage at treatment. Concentrations of 500 μg/ml or higher inhibited morphogenesis of nearly all organ primordia. In general, the effects of caffeine were concentration dependent and younger embryos were more susceptible to treatment than their older counterparts. Microscopic studies confirmed that the developing neuroepithelium was most sensitive to treatment. Caffeine, at concentrations sufficient to inhibit neural tube closure, caused no apparent alteration in the ultrastructure of cellular components except that apical microfilament bundles were thinner and less conspicuous than usual. Furthermore, caffeine (400 μg/ml) selectively inhibited uplifting of neural folds (and hence, closure of the neural tube) in embryos explanted at stage 8 and cultured for 4–6 and 16 hours. Affected neuroepithelial cells lacked the typical bottle‐shaped characteristic and folded apical surfaces. Overall results of this study suggest that caffeine causes neural tube defects, at least in part, through its inhibitory action on the contractile activity of apical microfilament bundles in developing neuroep

ISSN:0040-3709    

DOI:10.1002/tera.1420250104

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

年代:1982

数据来源: WILEY

摘要:

AbstractPregnant mice were treated with a single subcutaneous injection of either cyproterone acetate (CA) or medroxyprogesterone acetate (MPA). In the first experiment the animals received 5–900 mg/kg of the hormone before implantation (day 2 of pregnancy). CA treatment on day 2 caused a dose‐dependent decrease in fetal weight and a significant dose‐dependent increase in the rates of cleft palate and urinary tract abnormalities. Exencephaly and heart abnormalities were also significantly more frequent, but this increase was not dose‐dependent. MPA treatment on day 2 was followed by sporadic increases in dead and resorbed fetuses, a decrease in fetal weight and an increase in the rates of cleft palate and malformed or abnormally developed fetuses. None of these effects, however, was dose‐dependent.In the second experiment the mice were given one single injection (30 mg/kg) of CA or MPA on any one of days 1–12 of gestation. Treatment with CA on one day between days 1 and 12 revealed that the specific sensitivity for abnormalities of the urinary tract was on days 5 and 6, for the respiratory tract on days 8 and 9, and for cleft palate on days 10 and 11. Treatment with MPA on one day between days 1 and 12 only revealed a high rate of respiratory and urinary tract abnormalities on day 9. After treatment with MPA cleft palate was again significantly more frequent in all treated groups, however, days of peak sensitivity were not detected.The long half‐life of CA (60 hours) explains the teratogenic effect of high doses of this progestin after treatment on day 2 and also the pattern of abnormal development found after treatment with a single dose of CA on one of the days between day

ISSN:0040-3709    

DOI:10.1002/tera.1420250105

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

年代:1982

数据来源: WILEY

摘要:

AbstractPrenatal administration of 3,4,3′,4′‐tetrachlorobiphenyl, zeranol, or diethylstilbestrol was observed to delay parturition in the rat and result in a concomitant increase in perinatal mortality. Even among control animals, those litters in which birth occurred after the beginning of day 22 of pregnancy contained significantly fewer survivors one day after birth. Increases in the length of gestation were correlated with increased weight of newborn control pups independent of litter size. The relationship between weight and litter size was anomalous, however, in treated animals. Gestational length is a sensitive indicator of a developmental effect even in the absence of overt teratogen

ISSN:0040-3709    

DOI:10.1002/tera.1420250106

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

年代:1982

数据来源: WILEY

摘要:

AbstractChronic prenatal exposure of rats to diethylstilbestrol, zeranol, or 3,4,3′,4′‐tetrachlorobiphenyl produced quantitative and qualitative differences in the cumulative pattern of weight gain during pregnancy. Each of the three compounds, however, exhibited unique characteristics with respect to the effect of increased dose on this response, as well as in the relationship of reduced weight gain to perinatal mortality. The weight deficit after diethylstilbestrol treatment was found to reside in the dam herself, not in any compartment of the gravid uterus. The pattern of maternal weight gain is a useful indicator of developmental toxicity permitting discrimination among structurally diverse chemical a

ISSN:0040-3709    

DOI:10.1002/tera.1420250107

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

年代:1982

数据来源: WILEY

摘要:

AbstractTwo hundred and eighty‐five cases of TEF/EA occurring in North Carolina from 1952–1978 were reviewed. Except for a greater incidence of low‐birth‐weight infants and hydramnios during pregnancy, the cases appeared to be representative of the population. Clustering of cases over time was statistically confirmed. The cyclic variation suggested an association with an infectious agent. The variation of reported infectious hepatitis cases during the period of this study resembled the variation of TEF/EA cases that had no other documented congenital malfor

ISSN:0040-3709    

DOI:10.1002/tera.1420250108

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe aim of this study was to investigate the teratogenic action of cadmium (Cd) on the developing mouse limb. Pregnant mice (C57BL/6J strain) received an injection of 4mg/kg CdCl2on day 8,9 or 10 of gestation. These animals and saline injected controls were sacrificed either on the day before birth or at various times up to 72 hours after injection.Limb defects occurred after treatment on each day, the most severe occurring after early treatment. The forelimb deformities were predominantly postaxial reduction while hindlimb defects were preaxial and involved reduction, hypertrophy, syndactyly and polydactyly. The most severe limb reductions were associated with abnormalities of the spinal cord.Eight to 12 hours after maternal injection with Cd on day 9, the cells of the neural tube and forelimb buds from affected embryos showed large numbers of cytolysosomes. In severely affected limbs both ectodermal and mesodermal cells were involved. In less affected limbs the cytolysosomes were restricted to the mesodermal cells immediately deep to the ectoderm. Right and left limbs appeared to be equally involved with damage extending throughout the craniocaudal length of the limb. By 24 hours most of the cytolysosomes had disappeared. In the neural tube they were replaced by large amounts of cell debris while in the limbs a range of morphology was seen. In the least developed limbs there were still some inclusions but also extracellular debris, while in other, more developed limbs, there was little or no sign of damage. By 48 and 72 hours after treatment all signs of cellular damage had disappeared. The wall of the neural tube however, was frequently thin and sometimes discontinuous while the limbs showed abnormalities in shape such as flattening of the postaxial margin and shortening of the anterior‐posterior axi

ISSN:0040-3709    

DOI:10.1002/tera.1420250109

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

年代:1982

数据来源: WILEY

摘要:

AbstractFetal rhesus monkeys were inoculated intracerebrally with an attenuated strain of western equine encephalitis virus. All animals developed micrencephaly. Twelve of sixteen monkeys developed ex vacuo hydrocephalus. All virus inoculated fetuses developed WEE virus antibody. Virus could hot be recovered at the time of delivery. Monkeys with the highest WEE antibody titers showed the greatest degree of hydrocephalus.

ISSN:0040-3709    

DOI:10.1002/tera.1420250110

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

年代:1982

数据来源: WILEY

摘要:

Abstract4‐Methylumbelliferyl β‐D‐xyloside was administered to 9‐day‐old chick embryos, and the morphological and chemical changes in the embryo were followed daily. Increases in wet weight, Na and Cl content, and visible edema were detectable at 10 days and fully apparent at 11 days. Dry weight increased to the same extent in control and treated embryos for four days, but then diverged. The degree of sulfation of chondroitin sulfate was slightly less in treated than control embryos at 10 days, and reached a steady low value at 11 days. Analysis of glycosaminoglycans in skin, muscle, and aorta showed an increase in chondroitin and its sulfates in the two former tissues but not the latter. In muscle and aorta, the degree of sulfation of chondroitin sulfate was markedly reduced; but in skin the results suggested a more complex picture in which the normal metabolism of glycosaminoglycans was altered. A possible physiological role is suggested for chondroitin sulfate in embryonic so

ISSN:0040-3709    

DOI:10.1002/tera.1420250111

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

年代:1982

数据来源: WILEY