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Biomedical subjects

M Jacobsen

Publications and source records attributed to M Jacobsen.

At least 73 records · Page 4Linked to original sources
PubMed1984

Emphysema and dust exposure in a group of coal workers.

The lungs of 450 coal miners who had been studied previously in a long-term epidemiologic project at 24 British mines have been examined post-mortem for signs of dust-related fibrosis and emphysema. Reliable estimates of cumulative (working-life) exposures to respirable mine dust were available for 342 of the men. The relative frequency of emphysema increased with age at death, and both panacinar and centriacinar emphysema occurred more frequently in smokers than in nonsmokers. The proportion of subjects with any emphysema was 47% in 92 men with no palpable dust lesions, 65% in 183 with small, simple pneumoconiotic lesions, and 83% in 175 miners with massive fibrosis (PMF). The chance of finding centriacinar emphysema in those with PMF increased significantly with increasing exposure to coal dust in life (p less than 0.025). A similar but less convincing relationship was found in those with simple pneumoconiosis (p less than 0.11), but in both groups, increasing amounts of ash with a given exposure to coal reduced the probability of finding centriacinar emphysema. The occurrence of centriacinar emphysema was associated also with increasing amounts of dust retained in the lungs. A preliminary exploration of this association did not support the hypothesis that emphysematous lungs clear dust less efficiently. We conclude that the association observed between exposure to respirable coal dust and emphysema in coal miners indicates a causal relationship. However, because it can be demonstrated only for men whose lungs show some dust-related fibrosis, it is suggested that the extent and nature of such fibrosis may be a crucial factor in determining the presence of centriacinar emphysema.

Age Factors↗
PubMed1983

The mortality of coke workers in Britain.

Two studies of coke workers in Britain, comprising 6,767 men, gave similar results. The proportion of lung cancer deaths was about 20% higher than in manual workers generally. The excess occurred primarily among younger men. The ratio of lung cancers to all other cancers was also higher than expected, with limited data showing no evidence of excessive tobacco consumption. Death rates from other causes were generally favorable. Overall the lung cancer death rates in oven workers were similar to those in non-oven men, but in both studies some indications of a job-specific excess were noted. These findings are compared with results from earlier studies in the United States and Canada where a much higher excess lung cancer mortality was found in oven men, particularly those with longer exposure times. We discuss possible reasons for the differences, and conclude that the results reported now contribute further evidence that exposure to coal carbonization fumes can cause lung cancer.

Adolescent↗
PubMed1983

Possible liver cell differentiation in testicular germ cell tumours.

Germ cell tumours may imitate various structures of the developing embryo and foetus. Certain structures have, however, very rarely or never been observed in these tumours. Thus the presence of hepatic tissue in testicular germ cell tumours has not been reported. In a series of 37 non-seminomatous testicular tumours seven tumours contained epithelial structures showing morphological and functional resemblance to liver cell trabeculae. These structures were present in tumours with yolk sac tumour (YST) components and most of the tumours also contained teratoid elements. With the immunoperoxidase technique the epithelial structures were heavily stained for alpha-foetoprotein (AFP) and ferritin in all cases, while positive staining for albumin, prealbumin and transferrin was occasionally found. Alpha-I-antitrypsin and haemoglobin F were demonstrated in few scattered cells. Whether or not these epithelial structures should be included among the various patterns of YST or considered to be teratoid components is uncertain. It is suggested that examinations of the heterogeneity of the concomitant serologic AFP may support one or other assumption.

Cell Differentiation↗
PubMed1983

Alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) in testicular germ cell tumours. A prospective immunohistochemical study.

189 orchidectomy specimens with germ cell tumours (95 pure seminomas and 94 non-seminomas) were studied for the presence of alpha-fetoprotein (AFP) and human chorionic gonadotropin (HCG) with the indirect immunoperoxidase technique. All seminomas were AFP negative, while 66% of the non-seminomas were positively stained for AFP. 21% of pure embryonal carcinomas (EC), 25% of EC components in mixed tumours, all yolk sac tumour (YST) components, 20% of pure teratomas (T) and 47% of T components were AFP positive. In EC and YST the immunohistochemical staining depicted characteristic previously unrecognized histological structures, presumably representing patterns of further differentiation. HCG was demonstrated in all choriocarcinoma (CC) components in the syncytiotrophoblasts and in syncytiotrophoblast-like cells (STLC) in 8% of seminomas and 30% of non-seminomas. 70% of all non-seminomatous tumours were positively stained for AFP and/or HCG. Neither AFP nor HCG positivity of the tumour tissue was especially associated with metastatic disease. Carcinoma-in-situ (CIS) present in seminiferous tubules adjacent to the tumours was never positively stained for AFP, but for HCG in a few cases.

Choriocarcinoma↗
PubMed1983

Ferritin (FER) in testicular germ cell tumours. An immunohistochemical study.

189 orchidectomy specimens with germ cell tumours were studied for the presence of ferritin (FER) using the indirect immunoperoxidase technique. FER was demonstrated in 93% of seminomas and 90% of non-seminomas. Various epithelial cell types in embryonal carcinoma (EC), yolk sac tumours (YST) and teratoma (T) were FER positive. Carcinoma-in-situ (CIS) which was present in the seminiferous tubules adjacent to the tumours was positively stained for FER in 94% of the specimens whether the tumour was a seminoma or a non-seminoma indicating a functional relationship of CIS to seminomatous as well as to non-seminomatous germ cell tumours.

Carcinoma in Situ↗
PubMed1983

Immunohistochemical demonstration of hemoglobin F (HbF) in testicular germ cell tumors.

Increased serum levels of fetal hemoglobin (HbF) in patients with testicular malignancy have been suggested to be due to reactivation of HbF synthesis in the bone marrow. Since HbF is known to be present in the normal yolk sac, a series of 12 testicular germ cell tumors containing yolk sac tumor (YST) components and/or embryonal carcinoma (EC) were examined by the indirect immunoperoxidase technique for the presence of HbF in the tumor tissue. In nine tumors, the YST components, i.e., cells of the microcystic and reticular patterns as well as of endodermal appearance, were positively stained. In addition, groups of positively stained cells were found in the mesenchymal stroma of the tumors. In seven tumors, varied numbers of EC tumor cells were also HbF-positive. In the vessels positively stained, blood cells occurred to a variable extent. The appearance and distribution of HbF-positive cells in the YST components are in accordance with the various types of blood-forming cells hitherto accepted to be present in the normal conceptus during development. In addition, the staining results indicate that YST imitates not only the yolk sac proper, but also other fetal structures. Furthermore, the results support the suggestion, that the HbF in the peripheral blood of patients with testicular tumors may originate in the tumor tissue, and not necessarily in the bone marrow. Evaluation of HbF as a serologic tumor marker in such patients is, therefore, recommended.

Erythrocytes↗
PubMed1982

Severe acquired immunodeficiency in European homosexual men.

Four previously healthy Danish homosexual men developed Kaposi's sarcoma or opportunistic infections with fever of unknown origin and lymphadenopathy. One patient died of a Pneumocystis carinii pneumonia. Three patients had defective cell-mediated immunity with absent leucocyte interferon production and decreased proliferative response to mitogens and antigens. T lymphocyte helper subsets and natural killer cell activity were reduced. Unstimulated mononuclear cells produced leucocyte migration inhibitor factor. Two patients were sexual partners and three had never been to the USA, where cases of severe acquired immunodeficiency have been reported. Thus, the syndrome must also be suspected in European homosexual men who present with fever of unknown origin, opportunistic infections, or Kaposi's sarcoma.

Adult↗
PubMed1982

Intracellular plasma proteins in human fetal choroid plexus during development. I. Developmental stages in relation to the number of epithelial cells which contain albumin in telencephalic, diencephalic and myelencephalic choroid plexus.

The developmental stages of telencephalic, diencephalic and myelencephalic choroid plexuses in the human fetus and the morphology of choroid plexus epithelial cells in the various plexuses in different development stages were described on basis of PAS- and toluidine blue-stained material. Six different cell types were identified in various combinations in 4 different stages (I-IV). The number and distribution of albumin-containing epithelial cells in various plexuses in the different stages of development were investigated by indirect immunoperoxidase technique. Albumin-containing cells did not belong to a single cell type. The telencephalic plexus exhibited a staining pattern for albumin which was different from that of the diencephalic and myelencephalic plexuses. In the telencephalic plexus positive epithelial cells were frequent in stage I, whereas only a few positive cells were present in stage II and III. In contrast, 30-40% of the epithelial cells in both diencephalic and myelencephalic plexuses in stage I, II and III showed a positive staining reaction. Later in gestation less than 10% were positive. It is suggested that a main function of the diencephalic and myelencephalic plexuses early in gestation is associated with protein transport rather than with glycogen synthesis and storage which might be a major function of the telencephalic plexus.

Cell Differentiation↗
PubMed1982

Intracellular plasma proteins in human fetal choroid plexus during development. II. The distribution of prealbumin, albumin, alpha-fetoprotein, transferrin, IgG, IgA, IgM, and alpha 1-antitrypsin.

Individual choroid plexuses of human fetal brain at different developmental stages were investigated by an indirect immunoperoxidase technique. The number and distribution of prealbumin-, albumin-, alpha-fetoprotein-, transferrin-, IgG-, IgA-, IgM- and alpha 1-antitrypsin-containing choroid plexus epithelial cells were recorded. The distribution of prealbumin in choroid plexus epithelial cells differed from that of other plasma proteins identified in these cells. Prealbumin was present in more than 90% of the cells at all ages examined in contrast to albumin, alpha-fetoprotein, transferrin and IgG, which were found in less than 40% of the cells, and this proportion declined later in gestation to only a few per cent. The telencephalic plexus exhibited a staining pattern for the proteins, except for prealbumin, which was different from that of the diencephalic and myelencephalic plexuses. Double-staining and staining with polyvalent antiserum indicated that the same epithelial cells showed positive reaction for albumin, alpha-fetoprotein, transferrin and IgG. The results are related to the observation of a high concentration of plasma protein in fetal CSF which may result from transcellular transfer from blood to CSF across the choroid plexus epithelial cells.

Blood Proteins↗
PubMed1982

Immunohistochemical investigations of tumors of supposed fibroblastic-histiocytic origin.

The aim of this study was to localize alpha 1-antitrypsin, ferritin, and lysozyme by means of the indirect immunoperoxidase technique and to evaluate the significance of these antigens as markers of histiocytic differentiation in tumors of a supposed dual fibroblastic-histiocytic origin. The series comprised 31 malignant fibrous histiocytomas (MFH) of the pleomorphic, spindle cell, and myxoid types, four cutaneous fibrous histiocytomas, and four atypical fibroxanthomas, four dermatofibrosarcoma protuberans, and two osteoclastomas of bone. For comparison, 15 soft tissue sarcomas of various other types were examined. Of the MFHs of the pleomorphic type, 18 of 22 (82 per cent) were positively stained for alpha 1-antitrypsin and 12 of 22 (54 per cent) were positively stained for ferritin. Of the five MFHs of the spindle cell type, none was positively stained for alpha 1-antitrypsin, three were positive for ferritin, and one was positive for lysozyme. None of the myxoid variants (corresponding to grade I-II myxofibrosarcoma) was positively stained for either of the antigens. These results and the observations made on the cutaneous fibrous histiocytomas, atypical fibroxanthomas, dermatofibrosarcoma protuberans, and the various soft tissue sarcomas indicated that 1) alpha 1-antitrypsin is a valuable marker of histiocytic differentiation in both benign and malignant fibrous histiocytomas, 2) ferritin can be visualized in more than half of these fibroblastic-histiocytic tumors, and the presence of ferritin distinguishes the spindle cells of these tumors from fibroblasts of connective tissue and most fibrosarcomas, and 3) lysozyme, although a good marker of histiocytic differentiation in ordinary histiocytes and benign fibrous histiocytomas, is a poor marker of neoplastic histiocytes of malignant tumors. The results further support the concept that MFH is a tumor of a dual fibroblastic-histiocytic origin.

Ferritins↗
PubMed1982

Coalworkers' simple pneumoconiosis and exposure to dust at 10 British coalmines.

Five physicians' radiological assessments of coalworkers' simple pneumoconiosis (CWP) in 2600 coalminers at 10 British collieries have been studied in relation to the individuals' estimated lifetime (mean 33 years) exposure to respirable coalmine dust. Estimates of exposure were based on 20 years of observations at each colliery. Radiographic classifications were clearly associated with the measures of dust exposure. Important unexplained differences between some of the collieries were disclosed. Among men with similar cumulative dust exposures those with longer exposure time had higher prevalence of CWP. In general there was no evidence that the quartz concentrations experienced (average 5% of mixed dust) affected the probability of developing coalworkers' simple pneumoconiosis. Some men reacted unfavourably (two or more steps of change on the 12-point radiological scale) over a 10-year period to coalmine dust with a relatively high quartz content.

Adult↗
PubMed1982

Multivariate analysis of risk factors in patients with metastatic testicular germ cell tumors treated with vinblastine and bleomycin.

39 patients with testicular germ cell tumor metastases were treated with vinblastine intravenous bolus injection day 1 and day 36 and bleomycin intramuscularly twice weekly for 10 weeks. 8 patients had complete remission. 4 of these are alive with no evidence of disease for 91 + to 109 + months. Studied with Wilk's method for stepwise discriminant analysis tumor volume and performance status significantly predicted the patients who had complete remission. Studied with Cox's proportional hazard model for multivariate analysis hCG in the primary tumor, serum lactate dehydrogenase, performance status, and complete remission had a significant impact on survival. The information from the risk factors may be useful in a differentiated treatment of patients with testicular germ cell tumor metastases.

Actuarial Analysis↗