RESUMEN
2-Ethylhexyl stearate was investigated in an embryo-/foetotoxicity and teratogenicity study on rats according to OECD guidelines for the testing of chemicals (No. 414). Dose levels of 0 (arachidis oil), 100, 300 and 1000mg/kg body weight/day were administered by gavage. Dams tolerated the applied dose levels without any toxic effects. Pre- and post-implantation loss and mean numbers of resorptions were unaffected by treatment. All parameters were comparable with the animals of the control group. Skeletal and visceral investigations revealed no treatment-related malformations. For embryo-/foetotoxicity, teratogenicity and maternal toxicity a NOAEL of 1000mg/kg was deduced.
Asunto(s)
Anomalías Inducidas por Medicamentos/fisiopatología , Caproatos/toxicidad , Ácidos Esteáricos/toxicidad , Teratógenos/toxicidad , Anomalías Inducidas por Medicamentos/veterinaria , Animales , Relación Dosis-Respuesta a Droga , Femenino , Muerte Fetal/inducido químicamente , Embarazo , Efectos Tardíos de la Exposición Prenatal , Ratas , Ratas Sprague-DawleyRESUMEN
The W.T. Grant Foundation Asthma Risk Study was designed to prospectively examine children who were considered at a genetically increased risk for the development of asthma. The respective contributions of 11 potential risk factors, both environmental and biological, were assessed in order to determine their relative roles in affecting the early onset of asthma. This is a report of an inception cohort of children born to asthmatic mothers and followed for a 3-year period. All 150 families were recruited from the general community and living within 2 h of the National Jewish Center for Immunology and Respiratory Medicine (Denver, CO). Mothers in the index risk sample had been previously diagnosed with asthma and were recruited during their pregnancy through physician referrals and media solicitation. The index sample of 150 families was 92% Caucasian and predominantly middle class. The mean age of mothers was 29.3 years, and of fathers, 31.1 years. The main outcome was the determination of the early onset of asthma and its association with quantified risk factors. By age 3 years, 14 of the 150 children had developed asthma. Frequent illness, IgE levels at age 6 months, parenting difficulties, and early eczema were significantly associated with the onset of asthma (P = 0.003, P = 0.006, P = 0.01, and P = 0.03, respectively). Only frequent illness, elevated serum IgE levels, and parenting difficulties entered a predictive model where they were independently related to the development of asthma.
Asunto(s)
Asma/epidemiología , Edad de Inicio , Asma/genética , Estudios de Cohortes , Humanos , Inmunoglobulina E/análisis , Lactante , Modelos Logísticos , Factores de RiesgoRESUMEN
A number of in vitro assays have recently been developed that need further validation in order to judge their value for local tolerance testing. For this purpose, results from the following experiments were compared: (A) cytotoxicity testing in cell culture (neutral red assay); (B) tests with the chorioallantoic membrane of fertilized chicken eggs; (C) rabbit eye mucous membrane tests; and (D) occluded epicutaneous testing in human volunteers. The data presented indicate that in vitro testing with the first two methods yields reliable results with respect to the eye and human skin irritation data within homologous substance classes. A test procedure is proposed that involves comparative testing of the chemicals with unknown irritant properties together with known weak and strong irritants from the same class of chemicals as standards in the test series. This procedure seems to be suitable as a preliminary screen for identifying severe irritants prior to the performance of any in vivo studies. It would reduce the number of animals to be used in vivo and lead to the avoidance of exposure of animals to harmful substances.
RESUMEN
The intradermal test in mice is a valuable model for assessing dermal tolerance to chemical substances. The test material is administered intracutaneously to hairless or depilated mice through a fine syringe, the animals are killed after 24 hours and the treated skin is removed, dried and assessed for reaction area, erythema and oedema. The skin fragments can be preserved as a record of the findings. While direct transfer of the findings from mouse to man is likely to be misleading, the test is well suited to comparative studies. Moreover it requires only small numbers of mice.
Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Pruebas Intradérmicas , Pruebas Cutáneas , Piel/efectos de los fármacos , Animales , Tolerancia a Medicamentos , Ratones , Modelos BiológicosRESUMEN
In hand washing tests with detergents containing fluorescent whitening agents (FWAs), the amounts of whitener left on both hands were determined by TLC spectrophotometry: they varied from 0.06 mg to 0.17 mg. Whiteners of different chemical constitutions behaved in a very similar manner. After 24 hours the skin of the treated hands was virtually free of whitener.