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M Albin

Publications and source records attributed to M Albin.

At least 37 records · Page 2Linked to original sources

Survival in cohorts of asbestos cement workers and controls.

OBJECTIVES: To measure the impact on survival of being exposed to asbestos cement dust. METHODS: Survival of 866 asbestos cement workers and 755 controls was studied with Cox's proportional hazards regression models with age as the basic time variable. The effect of cumulative exposure up to the age of 40 was investigated in an internal analysis of 635 asbestos cement workers who had dose estimates. RESULTS: The death risk was higher for the asbestos cement workers than for the controls with a hazard ratio (HR) of 1.15 (95% confidence interval was 1.00 to 1.31). The increased risk found seemed to be confined to the period 20-40 years from start of employment. The estimates of the cohort effect were almost unaffected by adjustment for smoking habits. The estimates of the exposure effect rose with increasing dose (< 4 fibre-years/ml (f-y/ml): HR = 1.00, 4-9.9 f-y/ml: HR = 1.06, > or = 10 f-y/ml: HR = 1.35, for workers with at least five years of employment), and were higher when restricted only to deaths from malignant or non-malignant respiratory disease. However, none of the point estimates were significantly increased. Median age at death was two years lower in the high than in the low, exposure group. CONCLUSIONS: The results indicate that even a moderate asbestos exposure may shorten the median duration of life in an exposed population. Compared with the estimated effect on duration of life from ever being a smoker, that of ever being an asbestos cement worker was less, although that of having a high exposure was similar.

Adult↗

Radiological changes in asbestos cement workers.

OBJECTIVE: To explore associations between exposure to asbestos cement dust and radiographic findings in lung parenchyma and pleura. METHODS: Radiographs from 174 blue collar workers and 29 white collar workers from an asbestos cement plant formed one part of the study. Progression of small opacities was further studied in those 124 blue collar workers, for whom two radiographs taken after the end of employment were available. The median readings from five readers who used the full ILO 1980 classification were used. As exposure indices, time since start of employment, duration of employment, cumulative exposure, and average intensity of asbestos exposure were used. The influence of age and smoking was also considered in multiple logistic regression analyses. RESULTS: Small opacities (profusion > or = 1/0) were closely correlated with time related exposure variables, and showed weaker association with intensity based exposure variables. The odds ratio (OR) for small opacities was equal to 2.8 (90% CI 1.2, 6.7) in the > 30 f(fibre)-y/ml group, compared with those in the 0-10 f-y/ml group. Progression of at least two minor ILO categories after the end of employment was seen in 20%. Also, pleural thickening was closely related to time. By contrast, costophrenic angle obliterations were not associated with the time related variables, but closely associated with the intensity of asbestos exposure, and tended to occur during employment. The OR was 4.5 (90% CI 1.3, 15) in the > 2 f/ml group, compared with those in the 0-1 f/ml group. CONCLUSIONS: In these workers, exposed mainly to chrysotile but also to small amounts of amphibole, the risk of radiographically visible parenchymal abnormality was substantially increased and strongly dependent on time related exposure variables. Progression was found long after the end of exposure. The findings on costophrenic angle obliterations, supposed to be sequelae of benign pleural effusions, were consistent with an immediate reaction triggered by intense asbestos exposure.

Adult↗

Genetic polymorphism for glutathione-S-transferase mu in asbestos cement workers.

OBJECTIVE: To investigate whether a lack of glutathione-S-transferase mu (GSTM1) activity was related to an increased risk for adverse outcome after asbestos exposure. METHODS: A study was made of 78 male former asbestos cement workers, with retrospective cohort data on exposure, radiographical findings, and lung function. Venous blood samples were obtained for the analysis of GSTM1 polymorphism by the polymerase chain reaction technique. Chest x ray films were classified according to the International Labour Organisation (ILO) 1980 classification. Vital capacity (VC) and forced expiratory volume during 1 s (FEV1) were determined. Individual estimates of asbestos exposure were calculated, and expressed as duration of exposure, average exposure intensity, and cumulative dose. Data on smoking were obtained from interviews. RESULTS: The lung function in the study group was reduced, compared with reference equations. 23% of the workers had small opacities > or = 1/0, 29% circumscribed pleural thickenings, 14% diffuse thickenings, and 12% obliterated costophrenic angles. 54% of the workers were GSTM1 deficient. They were comparable with the other workers in age, follow up time (median 30 years), and duration of exposure (median 18 years), but had a slightly higher cumulated dose (median 18 v 10 fibre-years) than the others. Neither in radiographical changes nor lung function variables were there any differences between the different GSTM1 groups. The findings were similar when smoking habits and estimated asbestos exposure were taken into account. CONCLUSIONS: We could not show that lack of GSTM1 activity was related to an increased risk for radiographical or lung function changes in a group of asbestos cement workers, followed up for a long period after the end of exposure.

Aged↗

Asbestos, cement, and cancer in the right part of the colon.

OBJECTIVE: The aim was to investigate associations between exposure to mineral fibres and dust, and cancer in subsites within the large bowel. DESIGN: Pooled retrospective cohort studies. SUBJECTS AND SETTINGS: Blue collar workers, employed for at least one year in different trades; asbestos cement or cement workers (n = 2507), other industrial workers (n = 3965), and fishermen (n = 8092). MAIN OUTCOME MEASURES: Standardised incidence ratios (SIRs, national reference rates) were calculated for cause specific cancer morbidity between 1958 and 1989. The observation period began 15 years after first employment. RESULTS: The asbestos cement and cement workers had a slightly increased risk of colorectal cancer (SIR 1.5; 95% confidence interval (95% CI) 1.1-2.0). This was due to an increase only in the right part of the colon (SIR 2.5; 95% CI 1.6-3.8). The ratio of right (7th revision of the International Classification of Diseases ICD-7) 1530-1531)/left (ICD-7 1532-1533) colon cancer among the asbestos cement and cement workers of 4.8 differed significantly from the ratio both among the other blue collar workers (0.4) and among the fishermen (1.5). As the sensitivity and accuracy was insufficient, mortality data did not show the excess of cancers in the right part of the colon. CONCLUSIONS: An increased incidence of cancer in the right part of the colon was evident in the asbestos cement and cement workers. The distribution of cancers within the colon was noticeably different from that in other blue collar workers, indicating that our findings cannot be explained by socioeconomic confounding factors. A detailed and appropriate disease classification, based on incidence data, is necessary in order not to obscure or underestimate effects of exposure in epidemiological studies on colorectal cancer.

Asbestos↗

Retention patterns of asbestos fibres in lung tissue among asbestos cement workers.

Retention patterns in lung tissue (determined by transmission electron microscopy and energy dispersive spectrometry) of chrysotile, tremolite, and crocidolite fibres were analysed in 69 dead asbestos cement workers and 96 referents. There was an accumulation of tremolite with time of employment. Among workers who died within three years of the end of exposure, the 13 with high tremolite concentrations had a significantly longer duration of exposure than seven in a low to intermediate category (medians 32 v 20 years; p = 0.018, one sided). Crocidolite showed similar patterns of accumulation. In workers who died more than three years after the end of exposure, there were no correlations between concentrations of amphibole fibres and time between the end of exposure and death. Chrysotile concentrations among workers who died shortly after the end of exposure were higher than among the referents (median difference in concentrations 13 million fibres (f)/g dry weight; p = 0.033, one sided). No quantitative differences in exposure (duration or intensity) could be shown between workers with high and low to intermediate concentrations. Interestingly, all seven workers who had had a high intensity at the end of exposure (> 2.5 f/ml), had low to intermediate chrysotile concentrations at death, whereas those with low exposure were evenly distributed (31 subjects in both concentration categories); hence, there was a dependence between last intensity of exposure and chrysotile concentration (p = 0.014). Among 14 workers with a high average intensity of exposure, both those (n = 5) with high tissue concentrations of chrysotile and those (n = 10) with high tissue concentrations of tremolite fibres had more pronounced fibrosis than those with low to intermediate concentrations (median fibrosis grades for chrysotile: 2 v 1, p = 0.021; for tremolite: 2 v 0.5, p = 0.012). Additionally, workers who died shortly after the end of exposure with high concentrations of chrysotile and crocidolite had smoked more than those with low intermediate concentrations (medians for chrysotile 35 v 15 pack-years, p = 0.030; for crocidolite 37 v 15 pack-years, p = 0.012). The present data indicate that chrysotile has a relatively rapid turnover in human lungs, whereas the amphiboles, tremolite and crocidolite, have a slower turnover. Further, chrysotile retention may be dependent on dose rate. Chrysotile and crocidolite deposition and retention may be increased by tobacco smoking; chrysotile and tremolite by fibrosis.

Aged↗

Identification of chemical modification sites on metalloproteins by capillary electrophoresis.

Capillary electrophoresis (CE) has been used to separate the peptides obtained from tryptic digestion of ruthenium-modified cytochrome c. The modified peptide was identified from a comparison of the elution profile and absorbance characteristics of the native and modified proteins. Automatic fraction collection on the CE instrument provides sufficient amounts of this modified peptide for amino acid sequencing. Capillary electrophoresis has also been used to monitor the modification reaction and to optimize the modification efficiency. The methodologies have been extended to myoglobin in order to monitor the modification of multiple surface sites.

Animals↗

Abnormal thyroid function test results in patients with Fisher-Evans syndrome.

Thyroid function was evaluated in patients affected by Fisher-Evans syndrome (FES) and compared to that of patients affected only by autoimmune hemolytic anemia (AIHA) and to that of patients affected only by idiopathic thrombocytopenic purpura (ITP). The study population consisted of 20 patients with FES, 44 with AIHA and 20 with ITP. All patients were examined for thyroid function abnormalities and thyroid autoantibodies. Abnormal thyroid function test results were observed in 40, 25 and 10% of the patients, respectively. The prevalence of antithyroid antibodies (ATA) in FES was 25%; this is higher than the sum of the prevalences of ATA in patients affected only by AIHA (11.4%) or only by ITP (none). Subclinical primary hypothyroidism and hyperthyroxinemia with or without hypertriiodothyroninemia, with TSH serum levels below normal, were present in 20% and 10% of patients affected by FES, respectively. Of the former, 75% were positive for ATA. These results: i) confirm the high prevalence of abnormal thyroid test results in patients affected by AIHA, ITP and FES; ii) demonstrate the higher prevalence of autoimmune hypothyroidism in FES; iii) lead to the possibility of including FES as one of the multiple autoimmune syndromes.

Adolescent↗

The use of capillary electrophoresis in a micropreparative mode: methods and applications.

The ability to collect sufficient quantities of analytes from capillary electrophoresis for subsequent analyses is demonstrated. Fractions collected have been analyzed using the following techniques: capillary electrophoresis, mass spectrometry, and protein sequencing. Fractions can be collected directly into small volumes of buffer or directly onto membrane surfaces. Relevant parameters such as capillary diameter, mass loading, and separation parameters are addressed.

Amino Acid Sequence↗

Immunohistochemical study of 158 lung carcinomas.

Lung carcinomas were studied immunohistochemically and the results were related to type of tissue sample (bronchoscopic biopsies, surgical specimens, autopsies). All cytokeratins (CAM 5.2, PKK-1, AE1/AE3) reacted with virtually all adenocarcinomas, most squamous, and 65% of the large cell carcinomas, while CAM 5.2 was most efficient with the small cell carcinomas. CEA stained 33% and 60% of the small and large cell carcinomas, respectively, most adenocarcinomas, and 84% of the squamous cell carcinomas, among which staining decreased with dedifferentiation and was often focal. EMA reacted with 90%, and NSE with 20% of all histological types. There was no staining for NF. All antibodies, except EMA, were more efficient with surgical specimens. Our study implies that the cytokeratins we used work better with surgical material, but are generally comparable to monospecific cytokeratin antibodies. Also, EMA is a reliable marker for epithelial differentiation with all types of tissue samples. Moreover, CEA negativity in several poorly differentiated lung carcinomas might have implications in the differential diagnosis against pleural mesothelioma.

Carcinoembryonic Antigen↗

Chest x ray films from construction workers: International Labour Office (ILO 1980) classification compared with routine readings.

The extent of agreement between International Labour Office (ILO) and clinical readings of chest x ray films from construction workers was studied. From a survey of 5898 workers 258 subjects with a profusion of small opacities of > or = 1/1 and a stratified sample of subjects with profusion < 1/1 were selected. Only 41% of the films classified as ILO profusion category > or = 1/1 were clinically recorded as non-normal for the parenchyma. The proportion of films recorded as pneumoconiotic (or possibly so) was especially low for irregular opacities (22%), but increased with the profusion category (both rounded and irregular) as well as with the size of rounded opacities (p 3/11, q 12/25, r 3/4). Only with the profusion category > or = 2/1 were most of the films recorded as pneumoconiotic. The specificity and sensitivity were highest in the geographical areas where a few clinical readers had assessed many films each. The proportion of false negative clinical reports was low for circumscribed pleural thickening of the chest wall (9%) and diaphragmatic pleural thickening (6%). For calcified pleural changes and for the combination of diffuse pleural thickening and obliteration of the costophrenic angle, false negative reports were absent. The present study shows an unsatisfactory sensitivity for clinical compared with ILO readings as a means for screening the parenchyma of workers with a risk of pneumoconiosis.

Humans↗

Histological type of lung carcinoma in asbestos cement workers and matched controls.

Histological types of lung carcinoma were examined in a case series of workers exposed to asbestos cement dust (n = 29) and matched controls (n = 87). The proportion of adenocarcinomas was 31% among the exposed subjects and 15% among the controls (mid-p = 0.05). Among workers with high exposure the proportion of adenocarcinoma was even higher (45%, 5/11; mid-p = 0.03). The proportion of peripheral tumours tended to be higher among exposed cases than controls (24 v 12%, mid-p = 0.12). Lobe of origin did not differ, however, between exposed cases and controls. Thus the study indicates an association between the degree of exposure to asbestos and adenocarcinoma of the lung, and a peripheral rather than central localisation of the tumours, but with virtually the same distribution of lobe of origin as in the general population.

Adenocarcinoma↗

Hyporesponsiveness of human alveolar leukocytes to interferon-alpha and interferon-gamma inducers.

Leukocytes were obtained from bronchoalveolar lavages (BAL) of 36 patients including 10 with lung cancer, 15 with inflammatory lung diseases and 11 healthy control patients undergoing diagnostic investigation. The entire alveolar cell population responded weakly to the classic interferon (IFN) inducers: Newcastle disease virus (NDV), phytohemagglutinin (PHA) and lipopolysaccharide (LPS). This refers mainly to normal healthy volunteers. Alveolar leukocytes from patients with inflammatory lung diseases and nonsteroid treated lung cancer responded better to the interferon inducers than did cells from other patients. The IFN-alpha or IFN-gamma response of whole blood leukocytes to the same inducers was 10 to 100-fold higher than that of the alveolar cells. Alveolar macrophages from 6 healthy individuals and 3 patients with inflammatory lung disease were cultured in vitro for 6 days. The IFN response to inducers appears to depend on the origin of the cultured cells. It increased in the initially hyporeactive macrophages from healthy subjects and decreased in the relatively reactive cells from the patients with inflammatory lung diseases. We suggest that the hyporeactivity to IFN induction is a physiological state of the alveolar leukocytes which are a specialized cell population having constant exposure to inhaled agents such as dust, smoke, microorganisms and their by-products. The hyporesponsiveness to IFN induction of the alveolar cells may have an important physiological role in protecting lungs against hyperproduction of cytokines involved in the inflammatory and allergic reactions.

Adult↗

The effect of magnesium sulfate administration on cerebral and cardiac toxicity of bupivacaine in dogs.

The effect of acutely elevated serum magnesium on the CNS and cardiac toxicity of bupivacaine was studied. Anesthesia was induced in mongrel dogs with thiopental, 25 mg/kg, and ventilation was controlled. Sedation was maintained with fentanyl (25 micrograms/kg bolus and 5 micrograms.kg-1h-1) and pancuronium (0.15 mg/kg bolus and 0.05 mg.kg-1h-1) provided paralysis. Two hours after the thiopental bolus, all animals received an intravenous (iv) infusion of bupivacaine (1 mg.kg-1 min-1). The control group (5 animals) received bupivacaine only. The Mg++ group (5 animals) received MgSO4 140 mg/kg iv and 80 mg.kg-1 h-1 15 min prior to beginning the bupivacaine infusion. Lead II ECG, cardiac hemodynamics, and two-channel EEG were continuously monitored. Serum magnesium concentrations in the Mg++ group rose from 0.67 mM (1.3 mEq/L) to 2.42 mM (4.8 mEq/L). The bupivacaine infusion caused PR and QRS interval prolongation in both groups, but QRS widening was greater in the control group. QT interval corrected for heart rate (QTIc) lengthened only in the control group. A depression of left ventricular stroke work index (LVSWI) occurred to an equal extent in both groups. The seizure dose of bupivacaine was not different between the two groups: 12.9 +/- 2.3 (SEM) mg/kg in the control group and 13.9 +/- 2.5 mg/kg in the Mg++ group.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Mineral fibres, fibrosis, and asbestos bodies in lung tissue from deceased asbestos cement workers.

Lung tissue from 76 deceased asbestos cement workers (seven with mesothelioma) exposed to chrysotile asbestos and small amounts of amphiboles, has been studied by transmission electron microscopy, together with lung tissue from 96 controls. The exposed workers with mesothelioma had a significantly higher total content of asbestos fibre in the lungs than those without mesothelioma, who in turn, had higher concentrations than the controls (medians 189, 50, and 29 x 10(6) fibres/g (f/g]. Chrysotile was the major type of fibre. The differences were most pronounced for the amphibole fibres (62, 4.7, and 0.15 f/g), especially crocidolite (54, 1.8 and less than 0.001 f/g), but were evident also for tremolite (2.9, less than 0.001, and less than 0.001 f/g) and anthophyllite (1.7, less than 0.001, and less than 0.001 f/g). For amosite, there was no statistically significant difference between lungs from workers with and without mesothelioma; the lungs of workers had, however, higher concentrations than the controls. Strong correlations were found between duration of exposure and content of amphibole fibres in the lungs. Asbestos bodies, counted by light microscopy, were significantly correlated with the amphibole but not with the chrysotile contents. Fibrosis was correlated with the tremolite but not the chrysotile content in lungs from both exposed workers and controls. Overall, similar results were obtained using fibre counts and estimates of mass.

Adult↗

Mortality and cancer morbidity in cohorts of asbestos cement workers and referents.

Total and cause specific mortality and cancer morbidity were studied among 1929 asbestos cement workers with an estimated median cumulative exposure of 2.3 fibre (f)-years/ml (median intensity 1.2 f/ml, predominantly chrysotile). A local reference cohort of 1233 industrial workers and non-case referents from the exposed cohort were used for comparisons. The risk for pleural mesothelioma was significantly increased (13 cases out of 592 deaths in workers with at least 20 years latency). No case of peritoneal mesothelioma was found. A significant dose response relation was found for cumulative exposure 40 years or more before the diagnosis, with a multiplicative relative risk (RR) of 1.9 for each f-year/ml. No relation was found with duration of exposure when latency was accounted for. There was a significant overrisk in non-malignant respiratory disease (RR = 2.6). The overall risks for respiratory cancer, excluding mesothelioma, and for gastrointestinal cancer were not significantly increased. Surprisingly, colorectal cancer displayed a clear relation with cumulative dose, with an estimated increase of 1.6% in the incidence density ratio for each f-year/ml (but not with duration of exposure).

Asbestos↗