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Biomedical subjects

L Johansson

Publications and source records attributed to L Johansson.

At least 181 records · Page 10Linked to original sources
PubMed1990

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↗
PubMed1990

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↗
PubMed1990

Small cell carcinoma of the oesophagus: a clinical and immunohistopathological review.

Primary small cell carcinoma of the oesophagus (SCCO), histologically indistinguishable from its counterpart of the lung, is a rare tumour. Less than 100 cases are reported. A review of 558 consecutive patients with oesophageal carcinomas referred to our department revealed seven cases. These were studied and compared to a survey of 80 cases collected from 24 reports. The present results, as well as the survey, indicate a poor prognosis with rapid and widespread dissemination, and that death is attributed to distant metastases rather than local failure. Freedom from local symptoms was achieved in all seven patients, regardless of therapy modalities employed. A complete response of the primary lesion was observed in three patients after chemo- and subsequent radiotherapy. According to these findings the most suitable treatment approach seems to be the same as for small cell carcinoma of the lung. A detailed immunohistochemical analysis revealed more characteristics similar to small cell carcinoma of the lung than that of the skin, viz 'Merkel cell carcinoma'.

Adult↗
PubMed1989

Premature acrosome reaction in spermatozoa from lead-exposed mice.

Lead-exposed mice were found to show a significantly increased frequency of acrosome-reacted spermatozoa. The number of spermatozoa bound to the zona pellucida of denuded mouse eggs was also significant increased, probably as a result of an acceleration of the processes involved in the capacitation of the spermatozoa and thereby of the acrosome reaction. However, the ability of spermatozoa from the lead-exposed mice to penetrate the investments surrounding the oocyte, e.g. the zona pellucida and the plasma membrane, was significantly reduced. No significant differences were detected in the frequency of motile spermatozoa or in the swimming speed between spermatozoa from the lead-exposed and the control group of mice. These results indicate that the previously observed reduction in fertility after exposure to lead, may be due to a disturbed interaction of the spermatozoa with the oocyte.

Acrosome↗
PubMed1989

Myxofibrosarcoma in the left atrium originally presented as a cardiac myxoma with chondroid differentiation. A clinico-pathological report.

Malignant cardiac tumours located on heart valves are very rare. We report on a myxofibrosarcoma originally presented as a cardiac myxoma (CM), partly with chondroid differentiation, located on the posterior leaflet of the mitral valve. The tumor recurred twice, the first time disguised as a CM with only minor components of myxofibrosarcoma, and finally metastazised as a myxofibrosarcoma. Patient survival (40 months from first surgery) was surprisingly long and this may well reflect both the effectiveness of the combined radiation and cytostatic treatment and the histopathological features of the tumor.

Adult↗
PubMed1989

Histogenesis of cardiac myxomas. An immunohistochemical study of 19 cases, including one with glandular structures, and review of the literature.

To elucidate the histogenesis of cardiac myxomas, the literature has been reviewed, including all previous immunohistochemical studies, and an extensive immunohistochemical study of 19 cardiac myxomas has been undertaken with antibodies to factor VIII, desmin, vimentin, myoglobin, cytokeratin (CAM 5.2 and AE1/AE3), and S100 protein. In all cases, vimentin stained endothelial as well as "myxoma" (stromal) cells. In contrast, factor VIII only stained endothelial cells. In 16 cases, desmin stained cells in the vascular structures; in 5 cases, desmin stained myxoma cells. In 6 cases, S100 protein stained the myxoma cells strongly. Myoglobin was absent in all cases. In 1 case, CAM 5.2 and AE1/AE3 stained glandular structures. The results indicate the following: that most cardiac myxomas are true neoplasms derived from "embryonal rests"; that the various mesenchymal cells found in cardiac myxomas (myxoma cells, endothelial cells, smooth-muscle cells, fibroblasts, myofibroblasts, and chondroid cells), express differentiation, not histogenesis; that, apparently, only the myxoma cells are neoplastic; and that the glandular structures infrequently found in cardiac myxomas originate from entrapped foregut rests.

Desmin↗
PubMed1989

Merkel cell carcinoma: management of primary, recurrent and metastatic disease. A clinicopathological study of 17 patients.

The clinicopathology of Merkel cell carcinoma (MC) has been evaluated in 17 patients, and its outcome and clinical management in 14 of these. The histopathologic diagnosis was confirmed by electronmicroscopy and/or immunohistopathology. The location of the primary lesions demonstrated a predilection for the skin of the face and the extremities. The primary treatment usually consisted of a wide excision only. Four out of five patients with MC of the face suffered from local and/or nodal relapses, in contrast to only one out of seven patients with primary lesion on the extremities. The three patients treated for local recurrences and/or regional node metastases were alive and disease-free 22-72 months after recurrences. Three patients developed distant metastases. Two of these died within 4 months after initial diagnosis. One patient completely responded to chemotherapy. The high frequency of local recurrences would justify an excision with generous margins, except when the tumour is close to a vital structure. Radiotherapy could in these cases obviate the necessity for extensive operations. If the primary lesion is located on an extremity, regional lymphadenectomy seems only to be necessary whenever nodal involvement is suspected. Node dissection is also recommended for suspected nodes in the face or on the neck, but the guidelines for elective node dissections in these sites are not obvious since the results of salvage therapy were excellent and the location of relapses unpredictable.

Aged↗
PubMed1988

Environmental exposure to lead and arsenic among children living near a glassworks.

Concentrations of lead (Pb) in blood (B-Pb, geometric mean 34.6 micrograms l-1, n = 127) and inorganic arsenic (As) and its metabolites in urine (U-As, mean 5.1 micrograms/g creatinine, n = 35) did not differ between children living in a village close to a glassworks emitting both Pb and As and children living in a reference area. There was no significant effect on B-Pb and U-As related to parents working at the glassworks or consumption of domestically grown vegetables. Neither was there any significant effect upon B-Pb of sex, age, potentially lead-exposing hobbies, or consumption of canned foods. Boys had higher U-As than girls (5.8 vs 4.2 micrograms/g creatinine, p = 0.005), and there was a decrease with age (range 8.4-10.4 years, 27% per year, p = 0.01). Further, parental smoking habits had a significant effect on both B-Pb and U-As. In children of non-smoking parents the B-Pb was 30 micrograms l-1, in children with one parent who smoked 39 micrograms l-1 (smoking father 37, smoking mother 41 micrograms l-1) and in children with two parents who smoked 47 micrograms l-1 (p less than 0.001). The corresponding values for U-As were 4.2, 5.5, and 13 micrograms/g creatinine, respectively (p = 0.01).

Adult↗
PubMed1988

Lead-induced changes in the stabilization of the mouse sperm chromatin.

Long-term exposure of male mice to inorganic lead was previously found to reduce their fertility. In the present study chromatin stability in spermatozoa from such mice was investigated by means of quantitative cytochemical analysis. Sperm head sizes were determined and the capacity for nuclear chromatin decondensation (NCD) was evaluated after exposure to a solution of sodium dodecyl sulfate/dithiothreitol. A decreased uptake of propidium iodide (PI), a DNA intercalating dye, was found in spermatozoa from the vas deferens of the lead-exposed mice. However, after thermal denaturation of the DNA, the spermatozoa showed a higher uptake of PI in comparison to those of the controls. After reductive cleavage of S-S bonds with DTT and staining with a thiol-specific reagent (monobromobimane), significantly fewer reactive disulfide bonds were also observed in the spermatozoa. Furthermore, a significant delay in the capacity for NCD was noted. These findings indicate that exposure to lead increases the stabilization of the sperm chromatin, which in turn probably affects the decondensation of the nucleus, thereby interfering with the fertility of the mice.

Animals↗
PubMed1988

Progressive growth of a human pleural mesothelioma xenografted to athymic rats and mice.

A human malignant pleural mesothelioma was xenografted serially in athymic nude Rowett rats for 27 passages during 33 months. After the two initial passages (P), the take rate during P3-9 was 100% (192/192). The tumour grew progressively during P3-9 in 99% (190/192) and regressed totally in 1% (2/192). The take rate for the tumour xenografted to athymic BALB/c mice was also 100% (17/17) and no regressions were observed. During serial passaging in nude rats, the tumour-volume doubling time (TD) decreased from 6 days in P2 to 3 days in P8-9 (P less than 0.001) and then remained around 3 days during P10-25. A TD of 11 days in P1 (man-mouse) for tumours grown in mice decreased during 10 passages in rats to 4 days (P less than 0.005) when the tumour was transplanted to mice in P11. Light microscopic morphology of the tumour was retained in rats and mice. We believe that our experimental tumour model using the nude rat as a carrier of the xenograft will be useful for studies of human mesothelioma.

Aged↗
PubMed1988

Prognosis after withdrawal of chronic postinfarction metoprolol treatment: a 2-7 year follow-up.

In a randomized double-blind postinfarction study 301 patients were treated with either metoprolol 100 mg b.i.d. (n = 154) or placebo (n = 147) for three years. After the three-year treatment period the study preparation was gradually withdrawn over one week, followed by another 2-7 year follow-up. Mortality and morbidity data were studied both during the intervention period (reported elsewhere) and over the period following withdrawal of study therapy. During the period following the withdrawal of the trial preparation, there were 16 (14%) and 31 (24%) deaths in the previously placebo and metoprolol groups, respectively (P = 0.10). Corresponding figures for reinfarctions and cerebrovascular events were 15 (13%) vs. 12 (9%) and 14 (12%) vs. 9 (7%) (NS). From a Cox regression analysis taking 13 different variables into account, a model describing the risk for subsequent death was constructed. The model identified the following important variables: sex (relative risk (rr) = 2.4), beta-blocker withdrawal (rr = 2.1), performance on exercise test and digitalis treatment (rr = 2.3, P less than 0.05). The present results, as well as those from other studies, seem to favour continuous postinfarction beta blocker therapy provided that there are no severe side-effects from therapy. Digitalis therapy in postinfarction patients in sinus rhythm may have adverse effects on survival during long-term follow-up.

Adolescent↗
PubMed1987

Properties and catabolism of heat treated antithrombin III concentrate.

Heat treatment is employed to diminish the transmission of hepatitis when blood products are administered. It is possible that such a procedure could reduce the biological activity of the proteins and induce changes in structure and aggregation state. We have therefore made in vitro and pharmacokinetic studies of heat treated antithrombin III (AT III) concentrate using both radiolabelled and non-labelled preparations. The purification, heat treatment and the radiolabelling procedures did not induce any changes in the AT III molecules with exception of a decrease in heparin affinity in about 10% of the molecules. The in vivo studies using 125I AT III showed that the fractional catabolic rate was increased and the half-life was shortened by about 20-25% compared to our previous studies on non-heat treated AT III concentrate. Our present findings indicating a mean half-life of 3.0 days are quite comparable to studies by others on non-heat treated AT III, however.

Antithrombin III↗