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B Hallengren

Publications and source records attributed to B Hallengren.

46 records · Page 3Linked to original sources

Local anaesthesia and immunomodulatory effects of antithyroid drugs.

Propylthiouracil (PTU) and propranolol can suppress, while methimazole (MMI) can enhance, mitogenic activation of lymphocytes. The present study investigated whether this effect of PTU, as has been shown for propranolol, relates to local anaesthetic activity. MMI (1 mM) but not PTU (1 mM) reduced the action potential in rat skeletal muscle. Thus, PTU seems to lack local anaesthetic activity. Moreover, the recorded local anaesthetic capacity of MMI hardly explains the stimulatory influence of MMI on lymphocyte activation. Apparently, the interference of MMI and PTU with lymphocyte activation seems to be due to another mechanism than local anaesthetic activity.

Action Potentials↗

Unsuccessful DTIC treatment of a patient with glucagonoma syndrome.

Various chemotherapeutic modalities have been tried in the treatment of patients with malignant glucagonomas. Promising results have been reported after drug treatment with dimethyltriazenoimidazole carboxamide (DTIC). We present a patient with a metastasizing pancreatic glucagonoma, in whom treatment with neither DTIC nor with the combination of streptozotocin and 5-fluorouracil resulted in any noticeable improvement.

Adenoma, Islet Cell↗

Influence of hyperthyroidism on the kinetics of methimazole, propranolol, metoprolol and atenolol.

The kinetic profiles of oral methimazole 40 mg, propranolol 80 mg, metoprolol 100 mg and atenolol 100 mg were compared in hyperthyroid patients both during the hyper- and euthyroid states. for methimazole, neither the peak concentration (Cmax), the time to reach peak concentration (tmax), the elimination half-life (t 1/2) nor the area under the curve (AUC) value was affected by the hyperthyroid state. For propranolol and metoprolol, which undergo extensive presystemic clearance, the AUC values were lower (p less than 0.02) when the patients were hyperthyroid than when they had become euthyroid, but the t 1/2's were not significantly altered. For atenolol, there were no significant kinetic differences between the hyperthyroid and euthyroid states. The findings are compatible with the assumption that hyperthyroidism does not affect the kinetics of methimazole or atenolol, but that it may enhance presystemic clearance of propranolol and metoprolol.

Administration, Oral↗

Influence of beta-adrenoceptor blocking agents on lymphocyte function in vitro.

1 In order to assess whether beta-adrenoceptor blocking agents may have an immunomodulatory influence, the in vitro effect of propranolol metoprolol and atenolol on mitogenic activation of human peripheral blood lymphocytes was studied. To investigate further the mechanism of this influence, the effects of quinidine and two other membrane stabilizing agents were examined. 2 At 100 and 1000 mumol/l, both (+)-propranolol, (-)-propranolol and (+/-)-propranolol evoked a strong reduction of mitogenic lymphocyte activation. A similar effect was obtained with quinidine. Even at 1000 mumol/l metoprolol, had only a slight suppressive effect and atenolol had no suppressive influence at all. 3 It appears that propranolol may suppress mitogenic activation of lymphocytes, and that the effect may be ascribed to membrane stabilization rather than to beta-adrenoceptor blockade.

Adrenergic beta-Antagonists↗

Suppressor T lymphocyte function in Graves' disease.

To explore suppressor T lymphocyte function in Graves' disease, studies were performed in one group of patients in the hyperthyroid state and in another group in the euthyroid state after treatment. Peripheral blood lymphocytes were cultured for 1-7 days. Pokeweed mitogen (PWM; 1.25 micrograms/ml) was added at the initiation of the cultures or after 24 h. The degree of lymphocyte activation was assessed by measurements of the cellular uptake of [3H]thymidine and expressed in counts per minute (CPM). The suppressor lymphocyte function was estimated by a quotient between the maximum CPM values from cultures with and without preincubation. For the hyperthyroid group (n = 15) the quotient was 1.00 +/- 0.07 (mean +/- SEM), for the euthyroid patient group (n = 21) 1.12 +/- 0.05 and for the healthy control group (n = 21) 1.37 +/- 0.08. There was a significant difference between the quotients for the control group and the hyperthyroid (P less than 0.01) as well as the euthyroid (P less than 0.05) patient group. The quotients for the two groups of patients did not differ significantly. In conclusion, the present study supports the view of a defect in suppressor T lymphocyte function in patients with Graves' disease in the hyperthyroid state and indicates that this defect can persist in the euthyroid state after treatment.

Adult↗

Effects of antithyroid drugs on lymphocyte function in vitro.

The in vitro influence of 6-propylthiouracil (PTU) and methimazole (MMi) on mitogenic activation of human peripheral blood lymphocytes was studied in order to assess whether antithyroid drugs may have an immunomodulatory capacity. Lymphocytes were cultured for 72 h in the presence of phytohaemagglutinin (PHA; 1.25 microgram/ml), concanavalin A (Con A; 5.0 microgram/ml), or pokeweed mitogen (PWM; 2.5 microgram/ml). Antithyroid drugs were added to yield final concentrations of 1-1000 mu mol/liter. High pressure liquid chromatographic analyses verified that the expected drug concentrations in the incubation media were reached and maintained throughout the incubation period. The degree of lymphocyte activation was assessed by measurements of the cellular uptake of [3H]thymidine added after 48 h. PTU (at 1000 mu mol/liter) slightly suppressed PHA- and Con A-induced activation of lymphocytes but enhanced (at 5-500 mu mol/liter) PWM-induced activation. MMI (500-1000 mu mol/liter) enhanced not only PWM-induced activation but (at 1000 mu mol/liter) also enhanced PHA- and Con A-induced activation. Thus, PTU and MMI might interfere with mitogenic activation of lymphocytes. However, the effects were mainly recorded at drug concentrations exceeding those found in blood samples of patients treated with conventional doses.

Concanavalin A↗

Metabolic studies and glucagon gel filtration pattern before and after surgery in a case of glucagonoma syndrome.

A case of glucagonoma syndrome with necrolytic migratory erythema, glossitis, anemia, hyperglucagonemia and a malignant, pancreatic A-cell tumour in a 68-year-old male is described. Gel filtration of the highly elevated circulating glucagon immunoreactivity (2200 pg/ml) demonstrated 60% pancreatic glucagon and 30% "proglucagon". Metabolic studies before operation demonstrated suppression of the total plasma glucagon concentration on oral glucose tolerance test, unchanged total plasma glucagon concentration during intravenous glucose tolerance test and insulin-induced hypoglycemia. Administration of arginine was followed by a rise in both the pancreatic glucagon and the "proglucagon", whereas alanine increased only the pancreatic glucagon. The plasma somatostatin level was immeasurable preoperatively. Somatostatin infusion completely suppressed the release of the pancreatic glucagon but did not significantly affect the "proglucagon". After removal of the tumour the skin lesions disappeared and the total plasma glucagon values fell to normal levels (120 pg/ml). Also, other abnormal laboratory findings returned to normal, including the preoperatively observed renal glucosuria.

Adenoma, Islet Cell↗

Effect of alcohol on chemotaxis, adherence and phagocytosis of human polymorphonuclear leucocytes.

In view of the presumed increased susceptibility of chronic alcoholics to infectious diseases, the influence of alcohol in vitro on leucocyte adherence, neutrophil chemotaxis, phagocytosis and intracellular killing was investigated with highly standardized methods. A significant inhibitory influence on these leucocyte functions was found only at alcohol concentrations in excess of those obtained clinically. An interesting observation not reported before was increased adherence, phagocytosis and chemotaxis at low to moderate concentrations of alcohol.

Blood Bactericidal Activity↗