ISSN:0270-3211    

DOI:10.1002/tcm.1770040202

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

年代:1984

数据来源: WILEY

摘要:

AbstractA method for examining the viscera of rat and rabbit fetuses is described. Techniques used in detecting visceral alterations in rats and rabbits for routine teratogenicity screens have varied over the years. The method used should be quick and simple but at the same time must be accurate, reliable, and comprehensive. The procedure used in this lab is a complete and systematic necropsy of the fresh fetus requiring minimum equipment and time. The examination can be done immediately following cesarean section and yields an intact skeleton which can subsequently be processed for skeletal examination. The fresh specimen and the natural coloration of in situ organs makes color photography of visceral alterations clear and concise. Any lesion can be appropriately fixed for histopathic examination. This technique begins with the examination of the organs in the abdominal cavity and proceeds to the thorax. Of special interest is the procedure used to inspect the internal anatomy of the fresh fetal heart. A description of the internal examination of both rat and rabbit heads and eyes is also included.

ISSN:0270-3211    

DOI:10.1002/tcm.1770040203

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

年代:1984

数据来源: WILEY

摘要:

AbstractSister chromatid exchanges and chromosomal aberrations were studied in peripheral blood lymphocytes of 55 rubber workers (from two different plants) and 35 controls mainly employed in office jobs. In both plants an increased frequency of SCEs (P<0.05 for plant A and P<0.01 for plant B) was detected in nonsmoking rubber workers as compared with nonsmoking referents.When the SCEs of worker groups belonging to the different job categories were compared with referents, the only groups showing statistically significant increases in SCEs were the smoking workers from the weighing and mixing departments of factory A and the nonsmoking weighers of factory B. A slight increase in the SCE frequencies was seen especially among smoking workers employed in the chemical mixing departments.The frequency of structural chromosome aberrations was not significantly increased in the occupational groups studied, the only exception being the small group of nonsmoking weighers in plant B.Among both the exposed workers and the controls, smokers had a higher mean SCE frequency than nonsmoking referents. This difference was significant between the exposed smokers and nonsmokers of plant A (P<0.01) and between smoking and nonsmoking controls for plant B (P<0.001). In addition, the chromosome aberration frequency of smoking controls of plant A was significantly higher (P<0.01 when gaps excluded and P<0.05 when gaps included) than that of nonsmoking referents. Also, smokers among controls for plant B had an increased frequency of aberrations in their cultured blood lymphocytes when compared with nonsmokers. This difference was significant (P<0.05) when gaps were excluded.

ISSN:0270-3211    

DOI:10.1002/tcm.1770040204

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

年代:1984

数据来源: WILEY

摘要:

AbstractProcarbazine (PCZ) was tested for its ability to induce mitotic gene conversions at theadeandtrploci ofSaccharomyces cerevisiae, strain D4. The influence of the following factors was examined: growth phase of the yeast cells (log vs stationary phase), pH of the treatment solution, and addition of mouse S9 fractions prepared from different organs. The drug was found more toxic and mutagenic at low doses (up to 25 mg/ml) for log phase cells, and scarcely toxic but highly mutagenic, even at high doses, for stationary phase cells. PCZ activity was reduced by acidic pH, and suppressed by S9 mix.Gene conversions were also analyzed in the intrasanguineous host‐mediated assay performed in mice orally administered with PCZ. In such conditions PCZ was ineffective in stimulating mitotic gene conversions, probably owing to its inactivation in the acidic environment of the gastroenteric trac

ISSN:0270-3211    

DOI:10.1002/tcm.1770040205

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

年代:1984

数据来源: WILEY

摘要:

AbstractThe use of coal as a fuel in utility and other industries in the United States is increasing. Typically, these utilities store their coal outdoors in large piles, and rainfall on the piles produces a runoff containing hazardous inorganic and organic materials. Four coals of varying sulfur contents, all used for fuel in the United States, were tested. Organic materials were extracted from simulated runoffs of model coal piles and were tested for mutagenicity with aSalmonella/microsomal assay and for clastogenicity and cytotoxicity in Chinese hamster ovary cells. The extracts of the high‐sulfur coals and the lignite were more mutagenic and clastogenic than extracts from the low‐sulfur c

ISSN:0270-3211    

DOI:10.1002/tcm.1770040206

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

年代:1984

数据来源: WILEY

摘要:

AbstractONO‐802, a synthetic E1prostaglandin, was administered intravaginally via pessaries to Dutch belted rabbits at doses of 250, 62.5, and 12.5 μg/kg on days 6 through 18 of gestation. Rabbits in a vehicle control group were treated with pessaries that did not contain ONO‐802 during the same period. Another group of animals remained untreated throughout gestation. Necropsies were performed on rabbits found dead and on those killed on gestation day 30. Body weight, food and water consumption, and clinical signs were monitored during the experiment. Major organs were weighed when the dams were necropsied on gestation day 30, and litter and fetal data were collected.Abortion and maternal deaths occurred in drug‐treated groups. Body weight gains and food and water consumption were adversely affected by treatment particularly at the 250 and 12.5 μg/kg dose levels. Wastage (postimplantation loss) was significantly increased among treated groups (all dose levels), while other litter and fetal parameters were unaffected. ONO‐802 was not teratogenic at maternal and embryotoxic do

ISSN:0270-3211    

DOI:10.1002/tcm.1770040207

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

年代:1984

数据来源: WILEY

摘要:

AbstractThe synthetic prostaglandin ONO‐802 was administered intravaginally to Sprague Dawley rats at doses of 1.0, 0.5, and 0.125 mg/kg on days 6 through 15 of gestation. A vehicle control group was treated with pessaries that did not contain the drug while another group remained untreated. Body weight, food, water consumption, and clinical signs were monitored during the experiment. In Phase One, 20 pregnant animals from each group were sacrificed at term, major organs were weighed, and litter and fetal data were collected. In Phase Two ten dams per group were allowed to deliver their litters, and the offspring were evaluated for survival, growth, developmental signs, and physiological function. Selected F1offspring were retained to assess learning and emotional behavior or reproductive capacity.Administration of either 0.5 or 1.0 mg/kg of ONO‐802 resulted in a slight reduction in food consumption and body weight gain. Water consumption was increased both during and after the dosing period for the mid and high dose dams. Significantly increased weights for the heart, lungs, liver, adrenals, and ovaries and decreased weights for the thymus gland were noted at term sacrifice of the 1.0 mg/kg dams, whereas the 0.5 mg/kg group had increased weights of the adrenals and ovaries only. Litter parameters were unaffected by treatment. Weights of the female fetuses of the 1.0 and 0.5 mg/kg groups were significantly reduced when compared to controls. There were no significant drug‐related abnormalities among the F1offspring and no evidence that treatment of the F0dams affected the development, behavior, or reproductive performance of the F1offspring. Thus, ONO‐802 was not teratogenic when given to rats by the intravagina

ISSN:0270-3211    

DOI:10.1002/tcm.1770040208

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

年代:1984

数据来源: WILEY

摘要:

AbstractEndodermal cells isolated from the yolk sacs of day 3 chick embryos were able to activate metabolically cyclophosphamide. This was demonstrated by the cytotoxicity of cyclophosphamide to the endodermal cells themselves as well as by the ability of endodermal tissue to mediate a cytotoxic response in coculture with KB cells, a human tumor cell line unable to activate cyclophosphamide. Yolk sac endodermal cells from day 3 embryos were sensitive to cyclophosphamide when the drug was added immediately after the start of culture, but not when the drug was added after 24 hr of culture. The ability to metabolize cyclophosphamide by the day 3 embryo appeared limited to the endodermal cells of the yolk sac as cells derived from neither the embryo proper nor yolk sac mesoderm‐ectoderm tissue were positive in these tests. Using whole blastoderms, cyclophosphamide activation was detected as early as 12 hr of egg incubatio

ISSN:0270-3211    

DOI:10.1002/tcm.1770040209

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

年代:1984

数据来源: WILEY

ISSN:0270-3211    

DOI:10.1002/tcm.1770040210

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

年代:1984

数据来源: WILEY

ISSN:0270-3211    

DOI:10.1002/tcm.1770040201

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

年代:1984

数据来源: WILEY