ISSN:0040-3709    

DOI:10.1002/tera.1420090102

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

年代:1974

数据来源: WILEY

摘要:

AbstractPolydactyly (including triphalangy) in C57BL/10 mice inducedby various dosages of 5‐fluoro‐2′‐deoxycytidine given at gestation day IX or XI isdescribed. These data are compared with those on aplasias in order to elucidate whether polydactyly is truly supernumerary or is the result of malposition of limb e

ISSN:0040-3709    

DOI:10.1002/tera.1420090103

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

年代:1974

数据来源: WILEY

摘要:

AbstractSingle oral doses of aldrin, dieldrin, and endrin, 1/2 LD50incorn oil, administered to pregnant golden hamsters on day 7, 8, or 9 of gestationcaused a high incidence of fetal death, congenital anomalies, and growthretardation. The most frequent defects were cleft palate, open eye, andwebbed foot, often occurring in combination. Pregnant CD1 mice given equivalent oral doses of each pesticide on day 9 of gestation showed similar anomalieswithout concurrent increase in fetal mortality or growth impairment.

ISSN:0040-3709    

DOI:10.1002/tera.1420090104

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

年代:1974

数据来源: WILEY

摘要:

AbstractStudies of hair‐follicle development and scalp‐hair patterning innormal fetuses and children and in those with disorders of early brain development were indicative of the following hypothesis: hair directional slope is secondary to the plane of stretch exerted on the skin by the growth of underlying tissues during the period of downgrowth of the hair follicles, around 10–12 gestational weeks. The posterior parietal hair whorl was interpreted as the focalpoint from which the growth stretch is exerted by the domelike outgrowth of thebrain during the time of hair follicle development. Anomalies such as encephalocele and dicephaly, which must have antedated hair follicle development, showed expected aberrations in scalp patterning. Among patients with primarymicrocephaly 85% had altered scalp hair patterning, indicating an early onsetof the problem in brain development. This included 25% with no parietal whorl, a finding previously noted only in nonhuman primates. Aberrant scalp patterning was also found to be a frequent finding in five established syndromes, included Down syndrome, in each case being compatible with a problem in early brain development. Thus, aberrant scalp‐hair patterning may be utilized as an indicator of altered size and/or shape of the brain prior to 12 weeks of ge

ISSN:0040-3709    

DOI:10.1002/tera.1420090105

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

年代:1974

数据来源: WILEY

摘要:

AbstractWe examined the effect of cardioactive drugs on the heart rate of intact rat embryos at day 11 (25 somites) of gestation, the stage of development prior to cardiac innervation. Tested were the autonomic drugs methoxamine and isoproterenol, the β‐adrenergic receptor blocker propranolol, and the phosphodiesterase inhibitor theophylline. Our observations indicated that (1) methoxamine had no effect; (2) isoproterenol and theophylline caused in creases in the heart rate; and (3) propranolol inhibited the effect of isoproterenol but did not affect the response to theophylline. We concluded that our results are consistent with (1) Ahlquist's ('48) original concept of α and β adrenergic receptors and the observation that the heart has no α receptors, (2) with the role of cyclic‐AMP in the model of the adrenergic receptor proposed by Sutherland ('68), and (3) with the observations that the embryonic heart at this stage of development is not yet innervated and so is without the vagal reflex arc (Hogg, '57; Gome

ISSN:0040-3709    

DOI:10.1002/tera.1420090106

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

年代:1974

数据来源: WILEY

摘要:

AbstractBecause the teratogenic effects of 1‐ethyl‐l‐nitrosourea (ENU) were observed to be strain dependent, a hybridization experiment was made between the susceptible C57L/J amd the resistant AKR/J strains of mice. ENU induced mortality and malformations were found to be influenced by maternal, cytoplasmically transmitted, sensitivity and resistance factors. Apparently, the C57L/J strain contributes maternal traits enhancing fetal susceptibility, whereas the AKRsol;J strain contributes resistance factors. Their nature and function are unknown but several possibilities are proposed as to how they may lead to the genetic differences observed in ENU‐induced teratog

ISSN:0040-3709    

DOI:10.1002/tera.1420090107

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

年代:1974

数据来源: WILEY

摘要:

AbstractReovirus type 3 was able to induce various effects in fetuses depending on the period of gestation pregnant hamsters were inoculated. Inoculations on gestation days 1–5 resulted in a high rate of fetal deaths. Fetuses of females inoculated on days 9–11 all became infected, but survived and developed normally. Reovirus proliferated to high liters in placentas and uteruses and was recovered from amniotic fluids in higher titer than from fetuses. Presence of phloxinophilic cytoplasmic inclusion bodies in pathologic studies revealed a spectrum of fetal infection ranging from mild involvement of the epidermis and ora mucosa to widespread systemic disease involving skin, visual organs, skeletal muscle, and neural tissues as well as voluntary muscles. These findings were substantiated by immunofluorescence studies. Throughout these experiments pregnant animals remained in good health in spite of having relatively high and sustained viremias. In view of the ubiquitous distribution of reoviruses in nature, and their lack of interspecies differences, observations of their ability to induce serious transplacental infections as well as hydrocephalus in laboratory animals point to the desirability of continued study of their potential role in the etiology of human dise

ISSN:0040-3709    

DOI:10.1002/tera.1420090108

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

年代:1974

数据来源: WILEY

摘要:

Abstract“Syndrome fever” is a term used to characterize the prolific publication of “new” human congenital malformation syndromes in the last decade. One way to manage syndrome fever, that is, to assimilate and utilize efficiently its valuable informational by‐product, is to create nosologic communities composed of member‐syndromes which have close general and specific phenotypic similarities. The phenotypic community approach to human mal‐formation syndrome taxonomy is applicable to rare, family‐specific syndromes, to well‐known syndromes that have achieved firm, independent identities, and to mixtures of the two. A community of six syndromes, four of them apparently rare, is proposed. All share uterovaginal malformation, but neither this type nor any other single type of malformation is essential for a syndrome to merit membership in the community. Five of the six syndromes have distinc‐tive and and/or foot malformations. Four of the six share malformations of the urinary tract; in a fifth urinary incontinence probably reflects a subtle dysmorphism. Three of the six syndromes have anomalies of the aural appa‐ratus; in two this involves an association between severe renal dysgenesis and middle ear ossicle defects. The sharing of similar malformations involving several systems suggests that the respective causes of the syndromes act on the same developmental pathway(S). All six syndromes have occurred in a familial distribution; four are probably determined by major mendelian genes. Malformations of the axial skeleton are rare, but those of the distal extremities are common, in thefamilialsyndromes belonging to the group. The reciprocal tendency is found insporadicoccurrences of severe uterovaginal dysgenesis (Rokitansky‐Küster‐Hauser syndrome) and in those with so‐called nonspecific

ISSN:0040-3709    

DOI:10.1002/tera.1420090109

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

年代:1974

数据来源: WILEY

摘要:

AbstractThe cytogenetic effects ofCannabis sativawere studied in (a) embryonic rat fibroblasts and rat and human leucocytes exposed to 40–200 μg/ml of cannabis resin in vitro for 6–72 h, (b) embryonic rat cells and leucocytes from pregnant rats exposed to a teratogenic dosage of cannabis resin in vivo, and (c) leucocyte cultures from male Jamaican chronic cannabis smokers. The in vitro experiments showed depression of mitotic rate with increasing doses of cannabis resin. In both in vitro and in vivo studies the experimental groups showed no increase in the percentage of numerical or structural chromosome aberrations. It appears that the reported teratogenic effects of cannabis are not due to chromosome damage though they may be due to mitotic inhibi

ISSN:0040-3709    

DOI:10.1002/tera.1420090110

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

年代:1974

数据来源: WILEY

摘要:

AbstractA specimen of human symmelia was judged at first to be a male from the appearance and disposition of the pelvic viscera but histological study of the gonads later showed that it was a female. This raises the question of whether the preponderance of males with this abnormality might be explained, at least in part, by incorrect diagnosis of sex particularly where this has been based on gross appearances. The bladder, rectum, anus, and external genitalia were missing and the kidneys were replaced by a mass of renal tissue dorsal to the lower aorta. There was a single umbilical arrery which was identified as a persistent left primary umbilical artery. Within the lower limb were two femora, two tibiae, and one fibula. Secondary centers of ossification were present in the distal ends of the femora and the proximal ends of the tibiae.

ISSN:0040-3709    

DOI:10.1002/tera.1420090111

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

年代:1974

数据来源: WILEY