Prediction of risk for human developmental toxicity: how important are animal studies for hazard identification?

Article Abstract:

The toxic effects of drugs and chemical agents on the developing fetus are difficult to ascertain. The medical community is forced to rely on limited studies performed on animals and on less scientific data obtained from human studies. Many practitioners prefer not to extrapolate data obtained from animal studies to humans because 'laboratory rats are not like humans'. However, it is hard to ignore the developmental effects of toxic agents demonstrated in animal studies. A computerized human risk assessment tool was created to help physicians make decisions regarding the toxic effects of chemical agents on fetal development. The computer model was used to predict the effects of 175 compounds on humans, based on results obtained from animal studies using up to 14 species of animals. The ability of the agent to cause a mutation or cancer was included in the evaluation. The number of positive animal studies and the ability of the agent to cause a mutation, particularly in hamsters and subhuman primates, were highly predictive of developmental toxicity in humans. The fact that an agent was tested on subhuman primates was more predictive of human developmental toxicity than the actual result of the test. The model correctly classified the toxic compounds 63-91 percent of the time. Seventy-five percent of the agents that cause toxicity to human development could be predicted on the basis of animal studies. Unfortunately, false negative (identifying an agent as nontoxic when it is toxic) results occurred 25 percent of the time. The findings indicate that data derived from animal studies can be extrapolated to humans, and the more animal species affected by an agent, the more likely it will affect humans. However, the effect may not be the same in animals and humans. (Consumer Summary produced by Reliance Medical Information, Inc.)

Models, Health risk assessment, Biochemical toxicology, Toxicology

---

Pre-eclampsia and offspring's blood pressure, cognitive ability and physical development at 17-years-of-age

Article Abstract:

Preeclampsia is a serious condition of pregnancy in which a pregnant woman develops high blood pressure, protein in the urine, headache, and edema. This condition may have a genetic component, and some evidence exists that children born to preeclamptic mothers are at risk for high blood pressure. The present study makes use of a large database (33,545 people born in Jerusalem between 1964 and 1971) to investigate this issue. Records from the children of mothers who developed preeclampsia (428 cases, 145 girls and 283 boys; the condition has a low incidence in Jerusalem) were analyzed: other information was obtained from draft medical examination records. Results showed that daughters of preeclamptic mothers had higher diastolic and systolic blood pressure at 17 years of age than daughters of mothers who had not suffered from this disorder. For sons, systolic blood pressure only was increased. Birthweights were lower for both boys and girls among offspring of preeclamptic mothers. The body mass index was higher for boys only. No differences were found in average IQ test scores. After further statistical analysis, it was found that the development of preeclampsia in the mother was associated with a 2.30-times elevated risk of systolic blood pressure greater than 140 mm Hg among the daughters. Maternal preeclampsia was not associated with impaired growth or below average cognitive performance in children. (Consumer Summary produced by Reliance Medical Information, Inc.)

Hypertension, Complications and side effects, Pediatric diseases, Preeclampsia, Cognition disorders, Cognitive disorders, Hypertension in children

---

Effect of maternal smoking and age on congenital anomalies

Article Abstract:

To learn whether smoking by pregnant women or their husbands is associated with birth defects, data were analyzed from a large study (16,583 women) concerned with oral contraceptive use. The study was performed in Israel, and virtually all women received prenatal care. Health information concerning the parents and infants was also readily available. Included in this was a record of the number of packs of cigarettes per day smoked. In general, the rate of major and minor defects was the same for smokers and non-smokers. Major defects included abnormalities of the chromosomes, central nervous system, or heart, cleft lip, and diaphragmatic hernia. Increases in the incidence of some major defects in infants of mothers who smoked were noted, but were not statistically significant; nor were the increases associated with fathers who smoked. Older women (35 or older) had a significantly higher rate of minor malformations, and a substantially (but not significantly) elevated rate of major malformations. Methodological considerations are discussed that could limit the extent to which these results can be generalized. However, it appears that smoking is teratogenic (capable of causing birth defects) in the fetuses of older women. (Consumer Summary produced by Reliance Medical Information, Inc.)

Pregnant women, Smokers, Pregnancy, Complications of, Pregnancy complications

Similar abstracts:

• Abstracts: Predictors of neurodevelopmental outcome following bronchopulmonary dysplasia. Midfacial hypoplasia associated with long-term intubation for bronchopulmonary dysplasia
• Abstracts: Occupational and environmental medicine: meeting the growing need for clinical services. Occupational medicine
• Abstracts: Clinical prediction rule for pulmonary infiltrates. Bundle-Branch Block and In-Hospital Mortality in Acute Myocardial Infarction
• Abstracts: Reactions to the stings of the imported fire ant. Marine envenomations. The management of bite wounds
• Abstracts: Pregnancy hormone levels signal trisomy 21, improved screening, lower costs possible. Domestic violence intervention calls for more than treating injuries

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.