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Biomedical subjects

J H Godbold

Publications and source records attributed to J H Godbold.

42 records · Page 3Linked to original sources

A morphometric study quantifying the mucus content of proliferating colonic epithelial cells.

We report a quantification of the maximum mucus accumulation in proliferating rat colonic epithelial cells. The proliferative potential was determined by radioautographic study of one-hour pulse exposures to tritiated thymidine, mucous content was determined by Periodic-acid Schiff (PAS) staining. We examined 55 labeled mucous cells in 0.5- to 1-micrometer serial sections. The maximum thecal and nuclear profiles of these cells were photographed and their surface areas were determined utilizing a coordinate sensor. The data were expressed as a theca-to-nucleus (T/N) ratio. The maximum (T/N) ratio for a labeled mucous cell was 3.0. We performed a similar analysis on 22 unlabeled mucous cells from upper crypt regions and surface epithelium to derive the range of (T/N) ratios for terminally differentiated mature mucous cells. The range of (T/N) ratios from these cells was from 4.8 to 16.4. Our study shows that proliferative potential of mucous cells is determined by the interrelationship between mucus accumulation and nuclear size.

Animals↗

A long-term mortality study of workers occupationally exposed to metallic nickel at the Oak Ridge Gaseous Diffusion Plant.

This study was undertaken to determine whether mortality from respiratory cancer among workers occupationally exposed to metallic nickel at the Oak Ridge Gaseous Diffusion Plant (ORGDP) differed from that of workers at the same plant with no record of occupational exposure to metallic nickel or any nickel compound. A cohort of ,14 nickel-exposed workers and one of 1600' controls were identified. The members of both cohorts had a minimum follow-up period of 19 years. Mortality from respiratory cancer and from other causes was examined in both groups. The data showed no evidence of an increased risk of mortality due to respiratory cancer among the nickel-exposed workers. The exposed cohort experienced lower mortality than the controls, both in deaths due to respiratory cancer and in deaths due to all causes, although neither of these differences was statistically significant.

Adolescent↗

Neoplastic and life-span effects of chronic exposure to tritium. II. Rats exposed in utero.

A study was conducted to determine the effects on neoplasia incidence and life-span of exposure in utero to a major environmental radionuclide. Sprague-Dawley rats were continuously exposed to tritiated water (HTO) from conception through birth in doses of 0, 1, 10, 50, and 100 muCi HTO/ml body water. HTO administration was terminated at birth. Calculated cumulative doses during gestation were approximately 0, 6.6, 66, 330, and 660 rads of total body irradiation. Under these exposure conditions, the two highest doses resulted in sterile offspring. Animals surviving through 30 days postnatally were defined as the study population and observed until their deaths. Intrauterine exposures to doses up to 66 rads had no significant effects on either sex with respect to life-span, overall neoplasia incidence, incidence rate, or onset of mammary fibroadenomas. Females exposed to 330 or 660 rads were sterile and had lower incidence rates of mammary fibroadenomass than did controls; at 660 rads females had a lower incidence of overall neoplasia and reduced mean life-spans. Sterile male offspring had reduced mean longevity after irradiation at 660 rads. Regardless of dose group, females had significantly higher incidences of neoplasia and longer life-spans than males.

Adenofibroma↗

Neoplastic and life-span effects of chronic exposure to tritium. I. Effects on adult rats exposed during pregnancy.

Female Sprague-Dawley rats were continuously exposed to equilibrium levels of tritiated water (HTO) during pregnancy. The tritium activities were 1, 10, 50, and 100 muCi HTO/ml body water which provided cumulative, whole-body radiation doses of approximately 6.6, 66, 330, and 660 rads. Administration of the radioisotope was terminated at parturition. Throughout their life-spans and at autopsy, the dams showed an increased incidence of mammary fibroadenomas at exposure to 330 and 660 rads. Although the data for the incidence of malignant mammary neoplasms were consistent with a linear dose response, the small numbers of tumors preclude specific definition of the dose-response curve. Postexposure life-spans for dams chronically exposed to 66, 330, and 660 rads during pregnancy were reduced by 14, 24, and 22%, respectively. Accelerated aging was also demonstrated in these rats: The mean age for mammary fibroadenoma onset decreased with an increasing dose of radiation.

Adenofibroma↗

No association between serum cholesterol and growth in preadolescent American children.

To determine the relation between serum cholesterol level (SCL) and growth in preadolescent children (2-12 years of age) in the United States, we examined the association of SCL and three measures of growth in a national sample of American children from 1971 to 1974. We investigated three parameters: sitting height, standing height, and weight and undertook separate analyses for sex and race. We found no consistent statistically significant associations with any of these three measures of growth. This result did not change when we adjusted the data for age alone or for age, poverty index, serum protein level, and hematocrit. We conclude that growth in this population group is not dependent on SCL.

Body Height↗