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Biomedical subjects

J C Martin

Publications and source records attributed to J C Martin.

At least 199 records · Page 11Linked to original sources
PubMed1981

Luteolysis and cycle synchronization with a new prostaglandin analog for artificial insemination in the mare.

Over a period of three years, 165 cyclic or anestrous Hanoverian mares received 177 treatments with 2, 3 or 4 mg of a novel luteolytic prostaglandin analog, K 11941. Heat and ovulations, indicating luteolysis, were observed after an average of 3.98 and 7.62 days, respectively, in 88.04% of 142 treated cyclic, postpartum and anestrous mares, and mares after an early loss of the conceptus. All doses tested were effective in inducing luteolysis as confirmed by determination of progesterone blood levels in samples collected daily, in 70 of 80 mares studied (87.5%). Attempts to achieve control of the cycle by various methods revealed that with K 11941 given once or twice, alone or in combination with hCG and/or an GnRH analog (Hoe 766), one can effectively concentrate estrus periods and follicular growth patterns, but can neither synchronize nor concentrate ovulations. Since most of the mares treated were confirmed problem mares, the pregnancy rate of 40.0% from first insemination at drug induced estrus, was regarded as satisfactory when compared to a pregnancy rate of 43.8% obtained with natural breeding in the same population. No drug related clinical signs of side-effects were observed.

Journal Article↗
PubMed1981

The Seattle longitudinal prospective study on alcohol and pregnancy.

An unselected sample of 1529 women (predominantly white, married, and middle-class) were interviewed during pregnancy regarding their use of alcohol, nicotine, caffeine, drugs, and other variables. Subsets of offspring were examined to assess the relationship of self-reported maternal alcohol use to infant health and development. Multiple regression statistical tests were utilized to permit adjustment for other possibly confounding factors. The following are among those outcomes significantly related to increase maternal alcohol use after adjusting for smoking and other variables: smaller infant size (birth weight, length and head circumference); lower Apgar scores; poorer neonatal habituation; decreased sucking pressure; increased tremulousness and head-turns-to-left; decreased vigorous activity; and a higher frequency of minor dysmorphic characteristics combined with low birth weight and microcephaly. A drinking by smoking interaction was related to poorer newborn conditioning in two separate studies. Significantly lower mental and motor development and lower length and weight were found on follow-up of 468 infants at age 8 months. Follow-up studies continue.

Alcohol Drinking↗
PubMed1981

Voluntary activity in the aging rat as a function of maternal drug exposure.

Sixty-eight Sprague-Dawley derived primiparous rats were injected subcutaneously twice daily throughout pregnancy and the nursing period with either (1) 3.0 mg/kg of pure nicotine, (2) 5.0 mg/kg methamphetamine HCl, or (3) saline vehicle. Locomotor activity was monitored one night/month from 3-39 months of age in randomly selected male offspring. Significant differences in activity levels were found as a function of maternal treatment for 29 of 35 sessions. The contrasts revealed that methamphetamine offspring were the most active group and there was no shift in relative group positions over time. There was some evidence for periodic activity changes at 5, 6, and 12 month intervals. A trend test revealed a significant decline in activity in the 12 month period preceding death which was not drug-related but common to all groups. Theoretical implications are discussed.

Aging↗
PubMed1981

[Silicosis with a rapid and pseudo-tumoral course occurring in a case of pre-existant progressive and treated pulmonary sarcoidosis in a miner little exposed to silicosis risk : sarcoido-silicosis (author's transl)].

The authors report the case of a miner suffering from pulmonary and nodal sarcoidosis treated with corticosteroids where during a multivisceral exacerbation with iritis and erythema nodosum there developed rapidly progressive pseudo-tumoral silicosis. Pulmonary and nodal biopsies by thoracotomy revealed silicotic masses in the upper lobe, penetrated and bordered by sarcoid granulomas. In the middle lobe and hilar nodes, only sarcoid process was present. This new entity, sarcoido-silicosis, follows its own course, insensitive to corticosteroids. By virtue of its immune status, sarcoidosis favourised the rapid development of silicosis, the latter being unexpected since exposure had been moderate. Deficiency in the elimination of silica particles from the lungs is discussed. A trial of treatment using aluminium hydroxy-allantoinate did not lead to any conclusion.

Adrenal Cortex Hormones↗
PubMed1980

Teratogenic effects of alcohol in humans and laboratory animals.

The teratogenicity of alcohol has been demonstrated in humans through clinical studies, behavioral studies, and epidemiologic studies, and in animals through controlled laboratory experiments. In humans exposed to alcohol during gestation the effects can range from fetal alcohol syndrome in some offspring of chronic alcoholic women to reduced average birth weight in offspring of women reporting an average consumption of two to three drinks or more per day. The behavioral effects of such exposure may range from mental retardation in children with fetal alcohol syndrome to milder developmental and behavioral effects in infants born to social drinkers. In animals, exposure to alcohol in utero may result in death, malformation, and growth deficiency as well as behavioral and developmental abnormalities. The mechanisms of impairment and related risk factors are yet to be elucidated.

Abnormalities, Drug-Induced↗
PubMed1980

Time: a new parameter for kinetic measurements in flow cytometry.

The measure of time was used as an additional parameter on an existing flow cytometer to study the kinetics of enzyme activities and cell-stain interactions. By correlating all fluorescent signals from single cells with time, the dynamics of a reaction can be followed for several minutes. This advanced application of flow cytometry is easily implemented and can be incorporated into any flow cytometer that has two-parameter analysis capability.

Animals↗
PubMed1980

Correlation of the growth of Chinese hamster V279-17lb multicellular spheroids with cytokinetic parameters.

The volumes of Chinese hamster V279-17lb multicellular spheroids grown in spinner culture were measured and correlated to DNA distribution and cell volume distribution information. Spheroid growth curves were obtained over a 21-day period using both electronic cell volume measurements and microscope micrometer sizing. The spheroids were collected from the aperture tube after electronic sizing, and single cell suspensions were prepared via trypsinization. Saline-washed cells were then stained with mithramycin and analyzed as unfixed or ethanol-fixed cells for both cell volume and DNA fluorescence measurements. Spheroid growth was determined to have an initial 8- to 9-day rapid growth phase, and a slow phase from 10 to 21 days. The single cell volume distributions of cells obtained from spheroids were dependent on spheroid volume and the relative proportions of small volume noncycling cells to large volume cycling cells comprising the spheroids were also dependent on spheroid volume. DNA distribution data and dual parameter DNA distribution cell volume contour patterns obtained for single cells dissociated from spheroids were closely related to the measured spheroid volume and revealed that the fraction of small, hypoxic G0-like cells was greatest in old, large spheroids.

Animals↗
PubMed1980

Flow cytometric analysis of the effect 5-bromodeoxyuridine on mouse teratocarcinoma cells.

Several flow cytometric techniques were used to study the effects of 5-bromodeoxyuridine (BrdUrd) on the growth and differentiation of mouse teratocarcinoma cells. The teratocarcinoma system mimics embryogenesis, and the stem cells of this tumor, termed embryonal carcinoma (EC) cells, spontaneously differentiate in vitro to progeny that are morphologically, biochemically and biologically distinct from the EC cells. When cultures of EC cells were treated with 30 microM BrdUrd, a pleiotropic response was observed; i.e., certain parameters mimicked spontaneous differentiation but occurred 2-3 times more rapidly while others were inconsistent with, or diametric to, spontaneous differentiation. In one line of diploid EC cells in which tetraploidy accompanies spontaneous differentiation, the BrdUrd accelerated the appearance of the tetraploid population. Analysis of cell cycle distributions during the course of the BrdUrd treatment showed that virtually all of the cells had cycled 2 or more times and incorporated BrdUrd into both strands of DNA. Multiangle light-scattering and electrical impedance analyses indicated that with respect to these two parameters, cultures treated with BrdUrd for 3 days resembled spontaneously differentiating cultures of 6-8 days. However, BrdUrd treatment did not induce increases in the kinetics of esterase (EC3.1.1.) activities in teratocarcinoma cells that normally accompany spontaneous differentiation. Analysis of alkaline phosphatase (APase) EC (3.1.3.1) activities showed that unlike the decrease in APase activities which accompany spontaneous differentiation, BrdUrd treatment causes an increase in APase activities.

Alkaline Phosphatase↗
PubMed1980

Experimental study of pulmonary emphysema in rats exposed to coal dust and papain: effects on the infrastructure and the cell dynamics.

Experimental lesions of emphysema were produced in SPF rats after laryngotracheal injection of papain and coal dust. The infrastructural changes were investigated a different intervals. The lesions observed are progressive, characterized by atrophy and ruptures of the interalveolar septa, and the disappearance of pneumocytes II. Passage through the septa of mineral particles is enhanced and total dust clearance seems to be increased. The results are discussed in the light of alveolar clearance studies using Fe-59 and surface tension measurements on pulmonary washings.

Animals↗