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Biomedical subjects

L Johansson

Publications and source records attributed to L Johansson.

At least 145 records · Page 8Linked to original sources
PubMed1994

Sawdust-induced inflammatory changes in rat lung: effects on alveolar and interstitial cells in relation to time.

Exposure to sawdust and its contaminants, e.g., terpenes, may cause respiratory tract and lung parenchymal inflammation. To monitor these changes over time. Sprague-Dawley rats were exposed at one occasion to 2.5 mg sawdust or saline by intratracheal instillation. Flow cytometry analyses were done on bronchoalveolar lavage (BAL) cells. Lung tissue specimens were analyzed histologically and immunohistochemically. After one week, the number of BAL polymorphonuclear leukocytes was increased (P < 0.05, N = 8), followed at six weeks by increases of macrophages and lymphocytes (both P < 0.01, N = 8). Enhanced expressions of class II antigens and complement receptors on macrophages after one week were even more pronounced at six weeks, indicating cellular activation. The BAL findings, also including increased (P < 0.001, N = 8) concentrations of hyaluronan with progressing changes over time, confirmed the signs of inflammation, as did the histological analysis of the lung tissue specimens with an accumulation of polymorphonuclears, macrophages, and hyaluronan in the interstitium.

Animals↗
PubMed1994

Promotive effect by prostasomes on normal human spermatozoa exhibiting no forward motility due to buffer washings.

Prostasomes, small corpuscular organelles derived from the prostate gland, were isolated from human seminal plasma by means of ultracentrifugation and Sephadex G 200 chromatography to assess objectively their promotive effect on the motility of buffer-washed normal human spermatozoa exhibiting no forward motility. Prostasomes were efficacious in about 70% of these spermatozoa, and a maximum value was obtained with prostasomes at a concentration corresponding to a protein content of 0.7-0.8 g/l followed by a plateau at higher concentrations. Addition of albumin alone resulted in a similar response although at a somewhat lower level and about 50% of the spermatozoa were rendered motile with a maximum effect of albumin at about 2.5 g/l. Albumin concentrations exceeding 3 g/l were less active. At protein concentrations of 0.25 g/l, prostasomes were superior to albumin in every respect concerning the effects on various sperm movement characteristics. These divergent effects were abolished when comparing prostasomes corresponding to a protein concentration of 0.75 g/l with albumin at 2.3 g/l, i.e. at their respective optimum concentration. Heat treatment and ultrasonication of prostasomes did not affect their motility-promoting properties. Some problem of sperm dysfunction has generally been considered to be a major contributory factor to infertility. By supplementing sperm preparations with postasomes in cases of established male factor, the already poor quality spermatozoa may more frequently be rendered capable of fertilization after insemination.

Humans↗
PubMed1994

Enhanced recruitment of motile spermatozoa by prostasome inclusion in swim-up medium.

Prostasomes, which are prostate-derived organelles, were purified from human seminal plasma for inclusion in Earle's balanced salt solution (EBSS) medium with or without human serum albumin. These media were used for swim-up experiments and the subsequent analyses of sperm motility parameters at different incubation times. The yield of motile spermatozoa after swim-up in EBSS medium enriched with boiled prostasomes was increased by 32% compared with EBSS containing albumin. Native prostasomes were less active. Combinations of albumin and either prostasomes or boiled prostasomes significantly increased the recovery of motile spermatozoa and also increased the percentage of spermatozoa displaying progressive motility after 1 h of incubation. Media lacking albumin showed lower values regarding progressive motility after 22 h of incubation. A beneficial effect of prostasomes was noted on lateral head displacement and percentage of hyperactive spermatozoa during the first 6 h of incubation. These results suggest that inclusion of prostasomes, especially boiled prostasomes, in swim-up media may improve the recovery of hyperactive motile spermatozoa for up to 6 h in cases of established male factor infertility, and consequently increase the opportunities for fertilization.

Hot Temperature↗
PubMed1994

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↗
PubMed1994

Iodine-125 brachytherapy for clinically localized prostate cancer: a 5-year follow-up of outcome and complications.

Thirty-seven patients with clinically localized prostate cancer of all grades were treated by suprapubic digitally guided implantation of 125I seeds. The median age at the time of diagnosis was 68 years. The mean follow-up period was 62 +/- 19 months. At last follow-up 18 patients were clinically free of disease; 11 deaths occurred: 9 from prostate cancer and 2 from another disease. Complications occurred in 24 patients most commonly urgency and proctitis, attributable to the treatment. Four patients had severe late rectal complications, and 2 patients died of sepsis secondary to rectal fistulae. Digitally directed retropubic implantation of 125I appears inferior to other treatments of clinically confined prostate cancer both regarding outcome as well as complication rate.

Aged↗
PubMed1994

Ischemic and nonischemic tissue concentrations of felodipine after coronary venous retroinfusion during myocardial ischemia and reperfusion: an experimental study in pigs.

Tissue and plasma concentrations of felodipine, a dihydropyridine (DHP) calcium antagonist, retroinfused through the coronary venous system were studied in 27 pigs. The animals underwent 45-min myocardial ischemia followed by 4-h reperfusion. Felodipine (7 nmol/kg body weight) was administered in the coronary vein for 30 min, 5 min before reperfusion. Concentrations of felodipine in the ischemic and nonischemic myocardium and in plasma were determined by gas chromatography. In the ischemic area, felodipine concentration at start of reperfusion was 304 +/- 285, 171 +/- 160, and 52 +/- 47 nmol/kg (mean +/- SD) in the subepicardial, midmyocardial, and subendocardial layer, respectively. Corresponding concentrations in the nonischemic area were 15 +/- 13, 17 +/- 14, and 16 +/- 15 nmol/kg (p < 0.05 vs. ischemic area). Subepicardial concentration was highest at start of reperfusion, whereas concentrations in other layers peaked at the end of retroinfusion. The transmural concentration gradient of felodipine in the ischemic area decreased progressively during the reperfusion period. The nonischemic tissue concentration increased slightly during the reperfusion period. The plasma concentration was very low throughout the study (peak = 3.2 +/- 1.4 nM at 30 min). Coronary venous retroinfusion of felodipine resulted in profound accumulation of the drug, specifically in ischemic myocardium. The plasma concentration was low and did not affect systemic hemodynamics. Coronary venous retroinfusion is considered an advantageous technique for selective drug delivery.

Animals↗
PubMed1993

Cytogenetic analysis of six bronchial carcinoids.

Short-term cultures from four typical and two atypical primary bronchial carcinoids were cytogenetically analyzed. A lung metastasis from one of the atypical carcinoids was also analyzed. Of the four typical carcinoids, two had normal chromosome complements, while the other two had the karyotypes 46,X, -X, +7/47,XX, +7/47,XX, +X/46,XX and 47,XX, +7/46,XX. Both atypical carcinoids had chromosome abnormalities. One had the karyotype 45-46,X, -X,del(1)(q32),add(17)(p13), +add(19)(p13), -22, +r/47,XX, +X. The second carcinoid had the karyotype 78-81,XXY, +Y, +1,t(2;8)(q21;q24), +3, +4, +del(4) (q25), +5, +6,der(6)t(6;6)(q21;p21)x2, +7, +7, -10,add(14)(p11-13), +19, -21, +1-4mar. The metastasis from this carcinoid had the same aberrations, except that the del(4)(q25) had been lost and one to two markers had been gained.

Bronchial Neoplasms↗
PubMed1993

Recombinations of chromosomal bands 6p21 and 14q24 characterise pulmonary hamartomas.

Cytogenetic analysis of short-term cultures from seven pulmonary hamartomas revealed an abnormal karyotype in six of them. The most characteristic aberration was an exchange of material between 6p21 and 14q24, found in three tumours. Abnormalities of either 6p or 14q were seen in another two hamartomas. Other regions that were rearranged more than once were 12q (three times) and 17p (twice), sometimes in exchange with 6p or 14q and giving rise to complex derivative chromosomes. Only one tumour had aberrations that did not involve 6p, 12q, 14q, or 17p. These results-together with the data on three previously reported pulmonary hamartomas, two of which also had t(6;14)-show that recombinations between 6p21 and 14q24 are common, and hence probably pathogenetically important. The data support the view that these tumours are genuine neoplasms rather than developmental anomalies. The coexistence of a common 14q24 breakpoint in uterine leiomyomas and pulmonary hamartomas indicates that a gene important in the genesis of both tumours exists in this band.

Adult↗
PubMed1993

Arachidonic acid 15-lipoxygenase and traces of E prostaglandins in purified human prostasomes.

Human spermatozoa are associated with arachidonate 15-lipoxygenase activity. This activity could be due to 15-lipoxygenase in small organelles (prostasomes), which are known to bind hydrophobically to germ cells. This possibility was assessed by separating prostasomes from human spermatozoa by differential centrifugation and purifying them by gel filtration (Sephadex G-200). Purified prostasomes metabolized [1-14C]arachidonic acid to 15(S)-hydroxyeicosatetraenoic acid as determined by reverse phase and by chiral phase HPLC and by gas chromatography-mass spectrometry. Biosynthesis of prostaglandins could not be detected, but the prostasomes contained trace amounts of the four major E prostaglandins of human seminal fluid (3.6 nmol mg-1 of prostasomal protein). Arachidonic acid 15-lipoxygenase has recently been implicated in the acrosome reaction of bull spermatozoa and it may have a similar function in the acrosome reaction of human spermatozoa.

Arachidonate 15-Lipoxygenase↗
PubMed1993

Rapid induction of enterochromaffinlike cell tumors by histamine2-receptor blockade.

The effect of acid inhibition on gastric endocrine cells was investigated in Praomys (Mastomys) natalensis. Long-term treatment (1 to 32 weeks) with an irreversible histamine 2-receptor blocker (loxtidine) caused a sustained increase in plasma gastrin levels, which was accompanied by a gradual increase in histamine and histidine decarboxylase activity of the gastric oxyntic mucosa. The density of endocrine cells in the oxyntic mucosa increased gradually, doubled by 8 weeks, and was three times that of controls after 24 weeks of treatment. Hyperplastic changes in the endocrine cell population were evident after 2 to 8 weeks in all animals, whereas dysplastic or neoplastic lesions were observed in half the animals after 16, 24, and 32 weeks of treatment. Gross tumors in the oxyntic mucosa were observed in 1/4 of the animals treated for 24 or 32 weeks. Proliferating cells were identified as enterochromaffinlike cells because they were argyrophilic and immunopositive for chromogranin A and histamine. The results demonstrate that histamine 2-receptor blockade initiated by loxtidine promotes a rapid development of enterochromaffinlike cell tumors in Mastomys and suggest a critical role for gastrin in the formation of these tumors. However, the rate and frequency by which carcinoid tumors appeared in Mastomys after acid inhibition was much greater than that reported in other species, indicating that several factors, including hormonal and genetic factors, are important in the development of gastric endocrine tumors.

Animals↗
PubMed1993

Accidental deaths from asphyxia. A 10-year retrospective study from Sweden.

Accidental mechanical asphyxia is an unusual cause of death. In reviewing 73 cases occurring during a 10-year-period in Sweden, young boys and elderly women seemed to be most prone to this type of fatality. A striking number of victims had deliberately put a noose-like structure around the neck, and yet another group became entangled in some part of their clothing. Thoracic immobilization was seen in a number of cases, also involving work-related accidents. Hospitalized patients, asphyxiophilics and inebriated victims represent other risk groups. A case involving the use of a helmet is reported in view of the growing frequency with which Swedish children use bicycle helmets. The material contains only a few cases where the victim was not alone at the time of the accident, and it seems plausible that supervision could have prevented many of the reported fatalities. Public knowledge of accident mechanisms may increase the awareness of hazardous situations and activities. Spreading of the medical examiner's knowledge may thus form a basis for accident prevention.

Accidents↗
PubMed1992

Pseudodiploid karyotypes in adenosquamous carcinomas of the lung.

Pseudodiploid karyotypes with clonal structural rearrangements were observed in short-term cultures from two adenosquamous carcinomas (ASC) of the lung, a tumor type hitherto virtually uncharacterized cytogenetically. The karyotypes were 46,XX,der(1)t(1;14)(q44;q22),add(9)(q34) in the first tumor and 46,XX,i(17)(q10) in the second tumor. We suggest that ASC of the lung differ from other lung cancers by having pseudodiploid instead of massively aneuploid tumor stemlines.

Aneuploidy↗
PubMed1992

Effective dose from radiopharmaceuticals.

The effective dose, as defined by the International Commission on Radiological Protection (ICRP 1991), provides a possibility of expressing the radiation risk to patients undergoing different radiodiagnostic procedures by means of a single figure. This has been obtained by introducing organ or tissue weighting factors reflecting the radiation sensitivity of the organs. Such weighting factors were first published by the ICRP in publication 26 (1977), and have now been revised in publication 60 (1991). The effective dose for almost all radiopharmaceuticals in clinical use has been recalculated using the new weighting factors from ICRP 60 (1991) and compared with results from former calculations. A slight decrease in the numerical value for the effective dose has been observed, on average 11%. However, this does not correspond to a decrease in the estimated risk from the irradiation, since this has been re-evaluated and found to be higher than earlier believed (NAS 1990; ICRP 1991).

Humans↗
PubMed1992

Malignant melanoma of the nasal cavity and nasopharynx treated with cisplatin and accelerated hyperfractionated radiation.

Primary malignant melanoma of the nasal cavity and paranasal sinuses is an uncommon disease, accounting for only 0.5-2% of all malignant melanomas. The primary treatment has been surgery. The frequency of local recurrence is high and recurrence is also the major determinant of treatment failure. Here we report on six patients with locally advanced disease, four of whom were too advanced for surgery, who were treated with accelerated hyperfractionated radiation in combination with cis-platinum. Three of four patients treated for local recurrent disease achieved a local cure and died of disseminated disease after 9-21 months. One patient given preoperative cisplatin and radiation is still alive with no evidence of disease 34 months after the completion of treatment. The present protocol may be a useful approach to obtain local control with the possibility of long-term cure.

Aged↗
PubMed1992

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↗
PubMed1992

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↗