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Biomedical subjects

J C Wagner

Publications and source records attributed to J C Wagner.

At least 55 records · Page 3Linked to original sources
PubMed1987

Substance-abuse policies and guidelines in amateur and professional athletics.

Substance-abuse policies and guidelines in amateur and professional athletic organizations are described. Amateur athletic organizations, which are governed by the U.S. Olympic Committee or the National Collegiate Athletic Association (NCAA), have developed programs that include mandatory drug testing. Drugs banned by the two organizations include psychomotor stimulants, sympathomimetic amines, narcotic analgesics, anabolic steroids, miscellaneous central nervous system stimulants, and, in the case of the NCAA, certain street drugs. Professional organizations have been somewhat slower to follow and, with the exception of tennis, do not allow mandatory drug testing. Each formal drug-screening program includes penalties for violators. The enforcement practices of the organizations representing tennis, baseball, basketball, and football are described. One aspect unique to professional sports is the employee-assistance program, which allows the impaired athlete to receive treatment while continuing to play and receive a salary. As drug-control programs become more common in athletics, opportunities may arise for pharmacists to participate in the areas of drug information and educational services.

Doping in Sports↗
PubMed1986

Correlation between fibre content of the lungs and disease in naval dockyard workers.

In the period 1966-82 lungs from 333 workers who had been employed at a Royal Naval dockyard were referred to the MRC Pneumoconiosis Unit where they were investigated for the severity of asbestosis, the presence of tumours, and an assessment of mineral fibre content and the type and amount of mineral present. The occupational exposure to mineral dust has been coded for 189 of these cases. There is good correlation between the severity of asbestosis and the coded exposures, electron microscopic mineral fibre count, and the fibre count as seen under the light microscope. The information collected showed that mesotheliomas occurred in those who had had minimal or slight asbestosis, by contrast with the pulmonary carcinomas found in those with moderate to severe asbestosis. The amphibole (crocidolite and amosite) lung content correlated with severity of asbestosis.

Aged↗
PubMed1986

Inhalation of china stone and china clay dusts: relationship between the mineralogy of dust retained in the lungs and pathological changes.

A combined clinical, radiological, pathological, and mineralogical study was undertaken on 62 cases referred to the Medical Research Council Pneumoconiosis Unit by the Cardiff Pneumoconiosis Panel as Cornish china clay workers. Considerable pathological lesions were found in the lungs, both nodular and interstitial fibroses being present. Some men had worked with china stone but others had worked entirely with china clay. Nodular fibrosis appeared to be related to a high quartz content of the dust recovered from the lung, whereas among those with a high content of kaolinite dust in the lungs interstitial fibrosis was observed.

Adult↗
PubMed1986

Central lymph node changes and progressive massive fibrosis in coalworkers.

Lungs from 123 coalworkers coming to necropsy were examined to determine the association between dust related changes in the central lymph nodes and progressive massive fibrosis and secondary foci in the lung parenchyma. Increasingly extensive changes of the central nodes were scored macroscopically, the highest scores indicating erosion through the walls of adjacent bronchi or branches of the pulmonary artery or both. In 88 cases (mainly with extensive changes) microscopic assessment was also made. Increasingly extensive changes of central nodes were associated with the presence of progressive massive fibrosis in the lungs (p less than 0.001) and the presence of secondary foci in lungs without progressive massive fibrosis (p less than 0.03). Microscopic assessments agreed fairly well with macroscopic assessments, but tended to be assigned lower scores. A hypothesis for the pathogenesis of progressive massive fibrosis is proposed whereby dust, accumulating in central lymph nodes, leads eventually to spread through the capsule and rupture into bronchi or pulmonary vessels, thereby sending dust laden activated cells back into the lungs to produce progressive massive fibrosis. These preliminary results are consistent with the hypothesis but more detailed studies are required.

Coal Mining↗
PubMed1985

Erionite exposure and mesotheliomas in rats.

Epidemiological and environmental surveys in the Cappadocian region of Turkey have linked the high incidence of pleural and peritoneal mesothelioma in the occupants of some villages with the zeolite fibres released from the locally occurring volcanic tuff. In view of the low ambient fibre concentrations and the extraordinary incidence of mesothelioma a study to test the hypothesis of high biological activity for the zeolite fibres was required. Experimental studies using both intrapleural inoculation and inhalation techniques have been undertaken with the erionite from this region and from Oregon in the United States. Additionally a non-fibrous zeolite from Japan and a synthetic non-fibrous zeolite of similar chemical composition to erionite have been included in the experiments. In these studies the samples from Oregon and Turkey produced a very high incidence of tumours. All the rats inoculated intrapleurally with Oregon erionite and almost all those inoculated with the Turkish fibre died with a mesothelioma. Inhalation of the Oregon erionite induced a similar effect. No other dusts we have investigated have produced this high incidence of tumours particularly following inhalation. These studies demonstrate that we now have a valuable new fibre for experimental study and a possible hazard to man in regions other then Turkey.

Aluminum Silicates↗
PubMed1985

Mortality of factory workers in east London 1933-80.

The mortality of 3000 male factory workers, 1400 laggers, and 700 women factory workers in east London has been studied. The men were first employed between 1933 and 1964, the women between 1936 and 1942. Textiles were produced until the late 1950s as well as other asbestos products. Laggers were employed on contract in increasing numbers in later years. Crocidolite asbestos was used until the late 1950s as well as asmosite and chrysotile. Exposure of workers was graded according to the job into two categories, low/moderate and severe, and subdivided by duration of employment up to two years or longer. Mesothelial tumours accounted for 7.5% of the total mortality in men, and 9% in women with their longer follow up period. Lung cancer accounted for 20% of deaths in men and 14% in women. Both mesothelial tumours and lung cancer showed a dose response relationship. Histopathological examination of a series of predominantly postmortem specimens showed 22% of adenocarcinomas of lung among men and 21% in women. There was an excess of gastrointestinal tumours but no dose response relationship could be shown. Among severely exposed male factory workers there was an excess of deaths from cancer of the larynx and among severely exposed women of carcinoma of the breast and ovary. Twenty four deaths (2%) were due to asbestosis. There is an indication that the incidence of mesothelial tumours is declining but a further period of observation is required for confirmation.

Adult↗
PubMed1985

Comparison of tumour markers in malignant mesothelioma and pulmonary adenocarcinoma.

Immunohistological methods were used to investigate the presence of carcinoembryonic antigen, beta 1 pregnancy specific glycoprotein, beta subunit of human chorionic gonadotrophin, human placental lactogen, calcitonin, and keratin in formalin fixed tissue from 29 malignant mesotheliomas and 27 pulmonary adenocarcinomas. Malignant mesotheliomas were negative for tumour markers except for the beta subunit of human chorionic gonadotrophin and keratin, one and 13 cases respectively being positive for these. Pulmonary adenocarcinomas, however, were frequently positive for tumour markers--namely, carcinoembryonic antigen, beta 1 pregnancy specific glycoprotein, beta subunit of human chorionic gonadotrophin, human placental lactogen, calcitonin, and keratin. The presence of carcinoembryonic antigen and beta 1 pregnancy specific glycoprotein within an intrathoracic tumour is strong evidence against its being of mesothelial origin.

Adenocarcinoma↗
PubMed1985

Enhanced theophylline clearance secondary to phenytoin therapy.

This report describes two cases in which theophylline clearance accelerated markedly with concomitant phenytoin administration. Maximum calculated theophylline clearance ranged from 2 1/2 to 3 1/2 times baseline. Onset of the interaction began within five days of beginning concurrent therapy. With combined use, clinicians should be aware, when phenytoin is added, of the potential for reexacerbation of pulmonary symptomatology due to lowered serum theophylline concentrations.

Aged↗
PubMed1985

Collagen biosynthesis enzymes in lung tissue and serum of rats with experimental silicosis.

The activities of prolyl 4-hydroxylase, galactosylhydroxylysyl glucosyltransferase (GGT) and lysyl oxidase (three enzymes catalysing post-translational modifications of collagen) were measured in the lungs of rats exposed to silica (DQ12). Circulatory levels of GGT were also estimated. Rats were killed after 24 h and at 6, 12 and 24 weeks after a single intratracheal instillation of either 12.5 or 25 mg of silica (DQ12). Control animals received saline. The total activity of the three enzymes in the lungs of the exposed animals was significantly increased at all times (P less than 0.05). The circulatory levels of GGT were also increased though some differences failed to reach significance. Thus increased activities of enzymes of collagen biosynthesis correlated with the development of silicosis and occurred within 24 h of treatment. This suggests that the changes responsible for the eventual development of fibrosis are operative within hours of dust exposure.

Aging↗
PubMed1984

The effect of fibre size on the in vivo activity of UICC crocidolite.

Standard (UICC) crocidolite was subjected to ball milling to reduce the length of the fibre. These milled materials and the original standard sample were injected into the pleural cavity of rats to determine their ability to induce mesothelioma. Previous in vitro work on the same materials had suggested that biological activity was related to fibres greater than 6.5 microns in length and that the material milled for 4 and 8 h did not contain fibres in this range and was biologically inactive. The results of the animal work, however, did not follow this pattern; mesotheliomas occurred in rats in all treatment groups including the 4 and 8 h milled samples. Examination of the tissues and the dust recovered from them showed the presence of fibres greater than the suggested threshold. Attention is drawn to the problems associated with drawing conclusions from size distributions and in vitro studies without considering in vivo mechanisms.

Animals↗
PubMed1984

Mast cells and inhalation of asbestos in rats.

Mast cell counts were performed on sections taken from the lungs of rats exposed by inhalation to different UICC samples of asbestos fibres for periods ranging from a few days to two years. A comparison of mast cell counts with grades of fibrosis showed that there is a sevenfold increase when there is interlobular linking of the fibrotic lesions (grade 5). Submesothelial mast cells showed a trend of increasing numbers with increasing exposure and with increasing subpleural thickening. Each type of asbestos produced a steady increase in mast cell numbers with increasing exposure. Two samples from animals exposed to chrysotile and two from animals exposed to amphiboles (crocidolite and amosite respectively) had 10 times as many cells as the control group after six and 24 months' exposure. Another amphibole, anthophyllite, produced 50 times more cells than were present in the control specimen appropriate for the heaviest exposure. These results are briefly discussed in relation to further exposure, smoking, and characteristics of the dusts.

Animals↗
PubMed1984

Pluripotential nature of mesotheliomata induced by inhalation of erionite in rats.

Mesotheliomata can be induced more rapidly and more frequently by inhalation of erionite than by asbestos inhalation. Erionite-induced tumours have in general a similar ultrastructural appearance to inoculum-induced pleural and peritoneal mesotheliomata. Unusual features of these tumours were the presence of dense-cored vesicles and cells staining positively for neuron-specific enolase which indicated the presence of endocrine cells. In addition, one tumour showed differentiation towards bone-forming cells. The expression of both epithelial and mesodermal characteristics demonstrates the pluripotential nature of mesothelial cells under certain circumstances.

Aluminum Silicates↗
PubMed1983

Angiotensin converting enzyme in the serum of rats with experimental silicosis.

The development of silicosis in rats given an intratracheal dose of silica was followed both by normal histological procedures and by measuring the level of angiotensin converting enzyme in the serum. The histological changes demonstrated a variable response due to the uneven deposition of material given by the intratracheal route. While the enzyme activity in the serum increased in the treated group it was not well correlated with the histological changes.

Animals↗