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Biomedical subjects

L Johansson

Publications and source records attributed to L Johansson.

At least 253 records · Page 14Linked to original sources
PubMed1978

Familial antithrombin III deficiency as pathogenesis of deep venous thrombosis.

A family including 18 members with decreased antithrombin III (AT III), measured with both a biological and an immunochemical method, is described. The pattern found on crossed immunoelectrophoresis, using heparin in the agarose in the first run, was normal, though the peaks were low. This suggests decreased synthesis of a normal protein in the affected members. AT III deficiency occurred in both the paternal and the maternal branch, of the above 18 persons had had at least one thromboembolic episode. Some of the episodes had been precipitated by the presence or occurrence of some predisposing event or circumstance. This suggests the possible occurrence of a gene making some of the maternal family members more susceptible to certain trigger factors, such as surgery, infection, pregnancy, and the puerperium. The mode of inheritance filled all the criteria for autosomal dominant transmission. Prophylactic treatment, preferably oral anticoagulants and/or dextran, is recommended for all persons with a low AT III concentration in any situation known to increase the predisposition to thrombosis. The effect of heparin in these patients is impaired since the heparin co-factor, which is identical with AT III, is lowered.

Adolescent↗
PubMed1978

A family with thromboembolic disease associated with deficient fibrinolytic activity in vessel wall.

Defective fibrinolytic activity is often a contributory factor in deep venous thrombosis. A family with a high incidence of venous thrombosis in association with such a defect is presented. Of 13 family members who had had thrombosis, 12 showed a defective capacity to release fibrinolytic activity from vessel wall after venous occlusion and/or infusion of DDAVP, a vasopressin derivative. The fibrinolytic activator activity of the vessel wall was normal in all cases. This seems to be the first family in which there is evidence of an inherited abnormal fibrinolytic activity.

Adolescent↗
PubMed1978

Effects of porcine plasmin on the coagulation and fibrinolytic systems in humans.

Pig plasmin (Lysofibrin) was given to 11 patients with phlebographically verified venous thrombosis, 2 of whom were treated two and three times, respectively. The effect on coagulation and fibrinolytic parameters was studied. The platelet count, Owren's P&P (prothrombin plus factors VII and X), plasminogen, factor XIII, and antithrombin III did not change during the treatment. All patients developed a proteolytic activity demonstrable on both unheated and heated fibrin plates. The fibrinogen decreased successively to very low levels, and parallel to this an increase in fibrin/fibrinogen degradation products was found. The factor VIII and factor V activities decreased immediately after each Lysofibrin infusion but normalized rapidly again. The factor VIII molecule, however, retained its reactivity to rabbit antiserum against factor VIII. Immediately after the plasmin infusion a decrease of both alpha2-macroglobulin (alpha2-M) and the rapidly reacting alpha2-antiplasmin was observed. alpha2-M decreased successively and in several of the patients values were unmeasurable for a period of some days. A complex formation between pig plasmin and the alpha2-antiplasmin was demonstrated in crossed immunoelectrophoresis. The complexes were rapidly cleared from the circulation. No interaction between the pig plasmin and the inhibitor of the plasminogen activation, alpha1-antitrypsin or inter-alpha-inhibitor, was found.

Adult↗
PubMed1977

Subcellular distribution, a factor in risk evaluation of pentachlorophenol.

Pentachlorophenol (PCP) is a potent uncoupler of mitochondrial phosphorylation in vitro and also interferes with microsomal detoxication functions in vitro. This favours flavin mediated oxygenation compared with flavin cytochrome P-450 dependent reactions. Gas chromatographic analysis of subcellular fractions, obtained by zonal centrifugation showed markedly lower PCP concentration in mitochondria and a high accumulation in microsomes compared with cytosol. This increases the likelihood that PCP in vivo causes a malfunction in microsomal detoxication.

Acetylation↗
PubMed1977

Disturbance of microsomal detoxication mechanisms in liver by chlorophenol pesticides.

The pesticide pentachlorophenol known as an uncoupler of mitochondrial oxidative phosphorylation was shown to disturb liver microsomal detoxication functions by a selective inhibition of the terminal oxygenation enzyme P-450. At lower concentrations the flavin moiety of this enzyme chain is not inhibited but rather is stimulated, whereby a qualitative shift in detoxication of aromatic amines from C-oxygenation to N-oxygenation is obtained. The effects were due to the pentachlorophenol itself and not to a metabolite. Similar effects of varying strength were also obtained with other chlorophenol pesticides; 2,4,di-, 2,4,6,-tri and 2,3,4,6-tetrachlorophenol, di- and hexachlorophen, tri- and nonachloro-2-hydroxydiphenyl ethers. The relevance of these findings to the possible synergistic influence of chlorophenols on the carcinogenic effects of polyaromatic amines and hydrocarbons is discussed.

Aniline Compounds↗
PubMed1977

Transcervical thymectomy with the aid of mediastinoscopy for myasthenia gravis: eight years' experience.

Fifty-eight patients with myasthenia gravis, including 12 children, underwent thymectomy. Eleven of them (19%) had total stable remission and 42 (72%) showed clinical improvement and were able to reduce their anticholinesterase medication. These two groups combined comprised 53 patients (91%). There was no operative or postoperative mortality. Histopathological examination of the resected thymuses revealed a tumor (benign thymoma) in 4 patients (7%), thymitis in 36(62%), and no pathological changes in 18(31%). Patients with few or no germinal centers tended to achieve remission more rapidly than those with numerous germinal centers.

Adolescent↗
PubMed1976

Determination of pethidine in plasma by electron capture gas chromatography after reaction with trichloroethyl chloroformate.

Pethidine (meperidine) is determined in plasma by electron capture gas chromatography after derivatization with trichloroethyl chloroformate. The analytical procedure involves extraction of pethidine and the internal standard from plasma and their separation from metabolites by partition chromatography. After purification of the eluate, the derivatization is accomplished with trichloroethyl chloroformate in the presence of anhydrous sodium carbonate. The reaction mixture is further purified with methanolic alkali before gas chromatographic analysis. Optimum conditions for extraction and derivatization, as well as the sensitivity and selectivity of the method are discussed. Owing to the high sensitivity the pethidine levels are determined in 0.1 ml of plasma. The smallest amount of pethidine determined by the method was 100 ng/ml. The relative standard deviation at the 50-ng level of pethidine added to 0.1 ml of plasma was 5.8%(n =8).

Buffers↗
PubMed1976

Congenital left ventricular apical aneurysm.

An aneurysm of the left ventricular apex was accidently discovered on chest X-ray in an otherwise healthy 3 1/2-year-old-girl. Pre-operatively performed heart catheterization and ciné-angiography were followed by successful surgical removal of the aneurysm. Microscopic examination showed that the three layers of the myocardium were present, although it was degenerated by fibrosis. This case belongs to the fibrous type of aneurysm, which is the most rare type, not associated with other developmental defects, usually asymptomatic until there is rupture and sudden death, or the condition is accidentally discovered on chest X-ray and treated surgically.

Child, Preschool↗
PubMed1975

Viability properties in autologous fascia lata heart valve grafts: a transmission electron microscopical study.

Four frame-mounted autologous fascia lata heart valve grafts in situ for 18 to 41 months as well as one free-mounted fascia cusp in situ for 10 years were examined by transmission electron microscopy (TEM). In all cusps, areas of well-preserved subcellular structures were found as well as areas with degeneration and fragmentation of both nuclear and collagen fibers. Fibrocytes, fibroblasts, and a special cell form, the myofibroblast, were encountered. The appearance of this last cell form may explain the shrinkage phenomenon encountered in these valves, all retrieved at reoperation because of valve dysfunction. Some of the fascial cells thus stayed alive within the bloodstream for up to 10 years.

Aortic Valve↗
PubMed1975

Central and peripheral circulation immediately after pulmonary surgery as related to sympathodrenal activity.

Catecholamine output and circulation were observed in connection with pulmonary surgery in one group of ten patients who were anaesthetized with halothane-N20-02-d-tubocurarine and who breathed spontaneously after operation. In another group of four patients who received a modified neurolept anaesthesia with phenoperidine-N2O-O2-d-tubocurarine and who were mechanically ventilated also after operation, catecholamine output and temperature were observed. In both patient groups, catecholamine output was normal during iperation. Adrenaline output increased by 400% the first postoperative hours, while noradrenaline output remained normal. Thereafter, noradrenaline output increased, while adrenaline output started to decrease. A subnormal body temperature was seen at the end of the operation. In two patients from the neurolept group, adrenaline output and temperature were recorded hour by hour; maximal adrenaline output concided with maximal temperature rise. In the patients from the halothane group, the pstoperative change in foot, calf and forearm blood flow correlated well with the change in catecholamine output. The central circulatory response to the symptahoadrenal stimulation was, however, found to be less pronounced than is ordinarily seen.

Adult↗
PubMed1975

Aortic valve replacement with frame-supported autologous fascia lata grafts. I. Technical consideration and early results.

During the period November 1969 to June 1972, a frame-supported autologous fascia lata graft was implanted in 71 consecutive patients with surgically treated aortic valve disease at the Department of Thoracic & Cardiovascular Surgery, University Hospital, Uppsala. The follow-up period was between 1 and 4 years. Eleven patients died within 28 days of the operation (16%) and 13 after discharge from hospital (18%); the cumulative mortality was thus 34%. Forty-five percent of the patients who died had associated cardiovascular or other diseases. The causes of death were infection (10), myocardial failure (6), myocardial infarction (3), cerebral damage (3), and intraoperative aortic dissection from the cannulation site (2). The majority of the deaths (88%) occurred within 6 months and all within 13 1/2 months after operation. Two fascia lata valves were removed because of endocarditis 23 and 26 months, respectively, after operation. Two valves were also removed on account of mechanical malfunction. The remaining 44 patients with fascia lata valves had returned to work. No embolic complications occurred, despite the fact that only patients with a concomitant prosthetic mitral valve or atrial fibrillation received anticoagulatant treatment. Haemodynamic studies of the valve in vitro and pressure measurements during the operation showed that the valve had a low primary systolic peak gradient of 0-16 mmHg. Certain modifications in the construction aimed at improving the haemodynamic properties of the valve are discussed. Increased stringency in the sterility precautions during the valve construction procedure may have contributed to the fact that early endocarditis, which is a serious complication, did not occur in any of the last 43 patients. As yet the observation time is too short to judge, however, to what extent susceptibility to infection and possible late changes of the valve can affect its function.

Adolescent↗