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Biomedical subjects

A Fischbein

Publications and source records attributed to A Fischbein.

At least 37 records · Page 2Linked to original sources

Respiratory findings among ironworkers: results from a clinical survey in the New York metropolitan area and identification of health hazards from asbestos in place at work.

Diseases associated with asbestos are prevalent in the construction trades primarily as the result of the previously widespread use of insulation materials containing asbestos in the building industry. Workers in metal related trades, who are employed at construction sites, but who do not routinely use such materials in their work, may also be at risk for asbestos hazards. To assess such risk, a clinical survey was conducted on 869 ironworkers from the New York metropolitan area. A high prevalence of abnormalities on chest radiographs was found. Three hundred and twenty nine (38%) of the examined workers had pleural abnormalities on their chest radiographs consistent with asbestos induced effects. The prevalence of radiographic abnormalities indicating interstitial lung disease was low (7%) as was the prevalence of restrictive pulmonary function impairment (7%). Association was found between forced vital capacity (FVC) and pleural abnormalities on chest radiographs. Although ex-smokers appeared to have the highest prevalence of abnormalities, regression analyses showed that duration of employment in the ironworkers' trade was the most important factor associated with them.

Asbestos↗

Persistent reactive airway dysfunction syndrome after exposure to toluene diisocyanate.

Two police officers developed asthma like illness after a single but prolonged exposure to toluene diisocyanate (TDI) by being in the immediate vicinity of a tank car that had overturned on a highway. One officer experienced upper and lower respiratory tract symptoms with chest tightness about 4.5 hours after initial exposure. Shortness of breath, cough, and wheezing were noted the following day. The other experienced symptoms immediately on exposure, developed shortness of breath 20 minutes later, and presented with wheezing four hours after that. Follow up examinations over seven years showed persistence of respiratory symptoms and continuation of airway hyperreactivity requiring treatment.

Accidents, Traffic↗

Impairments in functional subsets of T-suppressor (CD8) lymphocytes, monocytes, and natural killer cells among asbestos-exposed workers.

Peripheral blood leukocytes from asbestos-exposed workers were analyzed by dual color flow cytometry using monoclonal antibodies that identify developmental (HLA-DR) and functional (Leu 8) subsets of T helper, suppressor lymphocytes, and monocytes. An increase in the number of T suppressor cells was closely associated with a decrease in T lymphocyte functions while numerical defects in activated monocytes (Leu M3+Ia+) and natural killer cells (Leu 7+) were correlated with a depressed Th/Ts ratio. Furthermore, among asbestos-exposed workers with depressed T cell functions we have demonstrated a significantly higher number of the effector Ts (Leu 2+ Leu 8-) subset which regulates both the Th/Ts lymphocyte system as well as B cells and NK cell activities. These findings identified changes in the T suppressor feedback regulatory loop as being responsible for the immunoregulatory imbalance among long-term asbestos workers. In double blind analyses of demographic and radiographic data these phenotypic changes were not correlated with age, smoking history, or duration of exposure but were associated with radiographic evidence of asbestos-associated effects. This correlation established a direct link between asbestos exposure and the subsequent development of immune dysfunction.

Adult↗

Evaluation of right and left ventricular function in hard metal workers.

Ingested cobalt has previously been associated with the development of a congestive cardiomyopathy. Despite occasional reports of cardiomyopathy after industrial exposure to cobalt, this association remains controversial. In a study of 30 cemented tungsten carbide workers with a mean duration of exposure to cobalt of 9.9 +/- 5.3 years radionuclide ventriculography was performed to study right and left ventricular ejection fractions at rest and exercise. For the entire group, rest and exercise biventricular function was normal. There was, however, a weak but significant inverse correlation between duration of exposure and resting left ventricular function (r = -0.40, p less than 0.03). Workers with abnormal chest x ray findings (9/30) had relatively lower exercise right ventricular ejection fractions (45% +/- 6 v 52% +/- 7, p less than 0.02). An inverse relation was also found between rest and exercise right ventricular ejection fraction and severity of parenchymal abnormalities on x ray examination (r = -0.44, p less than 0.01 and r = -0.41, p less than 0.02). Diminished right ventricular reserve was probably due to fibrotic lung disease and early cor pulmonale. Although overt left ventricular dysfunction was not present, prolonged exposure to industrial cobalt may be a weak cardiomyopathic agent with unknown long term significance.

Adult↗

An analysis of the validity of self reported occupational histories using a cohort of workers exposed to PCBs.

An investigation was conducted to examine the validity of self reported work histories obtained from a sample of 326 capacitor manufacturing workers who had participated in an epidemiological study relating health abnormalities to exposure to polychlorinated biphenyls. Based on objective personnel records obtained for 288 members of the sample group, validity scores ranged from 20% to 100% with most falling between 70% and 75%. This validity range corresponded to misclassification proportions ranging from 13% to 29%. Exposure misclassification tended to be random for men but non-random for women (overestimation of exposure). By means of multiple regression analysis, the diversity of the job categorical pattern was found to be a significant independent predictor of validity. The factors sex, duration, and time lapse were also significant validity predictors but only interactively with job diversity. There were also indications that interviewer skill could be an important factor. Knowledge of the magnitude of these factor effects could be critical in planning retrospective epidemiological studies.

Data Collection↗

Immunotoxicology: environmental contamination by polybrominated biphenyls and immune dysfunction among residents of the State of Michigan.

In 1973, inadvertent contamination occurred in a special farm feed supplement for lactating cows. Polybrominated biphenyls (PBBs) were used in place of magnesium oxide resulting in serious harm to farm animals, including cattle, chickens, geese, ducks. Farm families, accustomed to eating their own products, were most heavily exposed. To study the impact of PBBs, 336 adult Michigan farm residents, 117 general consumers for comparison, 75 dairy farm residents in Wisconsin, who had not eaten PBB-contaminated food, were examined, as were 79 healthy subjects in New York City. Abnormalities in the Michigan groups included hypergammaglobulinemia, exaggerated hypersensitive response to streptococci, significant decrease in absolute numbers and percentage of T and B-lymphocytes, and increased number of lymphocytes with no detectable surface markers ("null cells"). Significant reduction of in vitro immune function was noted in 20-25% of the Michigan farm residents who had eaten food containing PBB. The decreased immune function detected among the PBB-exposed farm residents tended to affect families as a unit and was independent of exposed individuals' age or sex, pointing against the possibility of genetic predisposition.

Agricultural Workers' Diseases↗

Modified nucleosides in patients with acquired immune deficiency syndrome (AIDS) and individuals at high risk of AIDS: correlations with lymphadenomegaly and immunological parameters.

Patients with certain malignant diseases excrete in their urine elevated levels of modified nucleosides originating predominantly from the breakdown of transfer RNA (tRNA). Acquired immune deficiency syndrome (AIDS), often associated with rapidly progressing Kaposi's sarcoma (KS), is currently occurring in many countries. Male homosexuals are considered to be at highest risk of developing these disorders. We have previously reported that patients with AIDS excrete elevated levels of modified nucleosides. In this communication, we report on modified nucleoside levels measured in 77 male homosexuals without clinical manifestations of AIDS at the time of examination. A high frequency of abnormal nucleoside levels was found in this high-risk group. There was a trend towards higher levels in individuals with lymphadenomegaly, considered a prodrome of AIDS. Statistically significant correlations were found between some of the nucleosides (pseudouridine and dimethylguanosine) and degree of lymphadenomegaly. Pseudouridine, 1-methyl-adenosine and dimethylguanosine were inversely related to percentages of total T-lymphocytes (T11), suppressor T-lymphocytes (T8), and number of natural killer cells (Leu-7). These findings suggest that determination of urinary nucleoside levels may help identify individuals at high risk of developing AIDS.

Acquired Immunodeficiency Syndrome↗

Interstitial pulmonary fibrosis in an automobile body shop worker.

Interstitial pulmonary fibrosis (IPF) is often of uncertain etiology and is therefore named 'idiopathic' pulmonary fibrosis. Some occupational exposures, however, are known to cause interstitial fibrosis, asbestos and silica being well-known examples. We present clinical and pathological findings of a case with IPF and the results of microchemical analysis of inorganic particulate matter in the lung tissue. A very high lung burden of inorganic contaminants was found, including silica and metallic compounds. Emphasis is given to the importance of obtaining detailed occupational histories and conducting microchemical analysis of lung tissue in order to clarify etiological factors in cases with 'idiopathic' pulmonary fibrosis.

Aged↗

Oculodermatological findings in workers with occupational exposure to polychlorinated biphenyls (PCBs).

Oculodermatological findings, such as hypersecretion of the Meibomian glands, swelling of the upper eyelids and hyperpigmentation of the conjunctivae are considered typical of "PCB poisoning." They were common clinical manifestations of yusho and yu-cheng, two epidemics in Japan and Taiwan caused by the ingestion of rice cooking oil contaminated with polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans. To investigate the prevalence of such abnormalities in a population with long term occupational exposure to PCBs, a group of 326 workers employed in two capacitor manufacturing facilities were investigated in 1976, and 195 of these again in 1979. The median blood values of lower homologues of PCBs were 63 ppb (in plasma) in 1976 and 49 ppb (in serum) in 1979, and of the higher homologues 18 ppb and 17 X 5 ppb respectively. The prevalence of oculodermatological findings potentially related to the effects of PCBs were 9 X 4% and 13 X 3% at the two examinations. There was no significant association between such abnormalities and blood plasma/serum concentrations of PCBs. The observations in this work population exposed to PCBs differ from the yusho and yu-cheng experiences in that fewer clinical abnormalities were found. Suggestions are made that it may be inappropriate to extrapolate findings from the well known PCB poisoning episodes to exposures in occupational settings and that attention should be paid to the importance of polychlorinated dibenzofurans as an aetiological factor in human PCB poisoning.

Adult↗

Modified nucleosides in asbestos workers at high risk of malignant disease: results of a preliminary study applying discriminant analysis.

Patients with asbestos related malignant mesothelioma excrete high levels of modified nucleosides in their urine. The purpose of the present report was to explore further the usefulness of measuring these breakdown products of transfer RNA (tRNA) in male asbestos insulation workers who are at high neoplastic risk but without clinical signs of malignancy. Modified nucleoside levels (psi, m'A, m'I, m2G, and ac4C) were used as discriminator variables in a computer generated discriminant function in which 96% of the controls and 95% of the insulation workers were correctly classified. It was also found, using a similar multiple regression model, that 10 of 13 were correctly classified as having normal chest radiographs and 27 of 30 asbestos exposed subjects as exhibiting alterations in either the parenchyma, pleura, or both. The results suggest that measuring modified nucleosides levels in the urine of asbestos exposed workers, and perhaps others exposed to carcinogenic agents, has the potential for identifying, through multivariate statistical techniques, individuals who are at high neoplastic risk.

Adult↗

Liver function tests in workers with occupational exposure to polychlorinated biphenyls (PCBs): comparison with yusho and yu-cheng.

The results of liver function tests in a population manufacturing capacitors and transformers are presented. Two clinical field examinations were performed, one in 1976 when PCBs were still used in the manufacturing of the electrical equipment and one at the end of 1979, 2.5 years after discontinuation of PCBs use. A low prevalence of abnormal liver function tests was found and mean values for all tests were within normal laboratory ranges. At the initial examination, weak, but statistically significant correlations were found between log LDH and plasma levels of log HPCB (higher chlorinated congeners of polychlorinated biphenyls) and log TPCB (total polychlorinated biphenyls) among the female workers, while log gamma-GTP correlated significantly only with log HPCB among the male workers. A significant increase to abnormal levels of gamma-GTP was noted at the follow-up examination in both male and female workers, and preliminary results indicate significant correlations between gamma-GTP and serum levels of PCBs among the male workers. These findings are in accordance with previously reported data on populations occupationally exposed to PCBs, but differ from hepatic biochemistry findings in accidental poisonings due to ingestion of cooking oil contaminated with PCBs and related compounds, i.e., polychlorinated dibenzofurans (PCDFs) and polychlorinated quaterphenyls (PCQs). Hence, the importance of considering the related compounds as etiologic factors in PCB poisoning is emphasized.

Adult↗