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The aim of this study was to ascertain whether there is a period during early embryonic development of the rat that is particularly sensitive to hyperthermia. Pregnant Sprague-Dawley rats were partially immersed in a water bath at 43.5 degrees C until their core temperatures, monitored by a rectal
The teratogenic effect of maternal hyperthermia is well known in laboratory animals and is presumed to exist also in humans. The aim of our study was to describe the embryotoxic effect of long-term higher and lower incubation temperatures on the chick embryo. Chick embryos were incubated within days
Pregnant rats at day 9 were bathed in 43 degrees C water for 15 min. Maternal rats at day 15 of gestation were found pregnant with fetuses variously malformed externally, such as exencephaly, spina bifida, microphthalmia, anophthalmia, facial cleft, cleft lip and generalized edema. Fetal death
Mammalian embryos growing in vitro are harmed by short elevations in the culture temperature. However, a relatively mild hyperthermic exposure can induce thermotolerance, a transient state of resistance to the effects of a subsequent heat exposure. The present study examines the induction of
Hyperthermia is defined as a temperature of at least 1.5 degrees C over the normal core body temperature. It is a proven teratogen in animals and in humans. The type of defects induced by hyperthermia in experimental animals are: anencephaly/exencephaly, encephalocele, microphthalmia,
Maternal hyperthermia induces severe malformations in the central nervous system (CNS) in both humans and laboratory animals. These phenomena are accompanied by apoptotic cell death, especially in the developing CNS. Cardiovascular malformations in conjunction with skeletal and CNS abnormalities
The majority of patients with microphthalmos and colobomas have genetic disorders. This is a survey of non-inherited, sporadic microphthalmos. Such cases may occur in the Goldenhar, CHARGE and VATER associations; it may also be due to teratological agents, for instance maternal ingestion of drugs,
Pregnant rats were utilized to study the effect of maternal hyperthermia on fetal development. Eight groups of six to eight rats were exposed to ambient temperatures of 43-44 degrees C at various stages of pregnancy. All rats were killed on day 20 of gestation. Edema, microencephaly and
The effects of 1) X-irradiation and 2) hyperthermia at a temperature of 43 degrees C individually and in combination have been investigated using cultured 8-day mouse embryos. B6C3F1 embryos were exposed to 0.3-2.0 Gy of X-rays, 5-20 min of heating, or 5 min of heating and irradiation at 0.3, 0.6,
Our previous study showed an association between high fever-related maternal diseases during the second and/or third gestational months and a higher risk of multiple congenital abnormalities (MCA) in the population-based large dataset of the Hungarian Case-Control Surveillance of Congenital
Hyperthermia has been shown to be a teratogenic agent in a number of animal species. We have attempted to determine if maternal hyperthermia during early gestation might also be responsible for problems in human development. Eight retrospectively ascertained cases, in which high fever had occurred
In our recent studies on the effects of maternal hyperthermia on the embryonic guinea-pig, we have demonstrated two 'teratogenic windows' at embryonic days 13 and 21 (E13 and E21). E13 encompasses the period of the closure of the neural groove and anterior neuropore, and E21 the commencement of the
Guinea pigs were exposed to hyperthermia for 1 hr once or twice on day 11, 12, 13, or 14 (E11-E14) of pregnancy. The mean rectal temperatures were elevated by 3.4 degrees C-4.0 degrees C. This treatment resulted in a marked elevation of rates of resorption and developmental defects in embryos
Many cells die during normal prenatal development. Throughout postnatal life, production of new cells is balanced by death of older cells to maintain the normal mass of organs and tissues. In these situations, cell death is usually in the form of apoptosis, characterized morphologically by shrinkage
An episode of hyperthermia is not uncommon during pregnancy. The consequences depend on the extent of temperature elevation, its duration, and the stage of development when it occurs. Mild exposures during the preimplantation period and more severe exposures during embryonic and fetal development