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Biomedical subjects

B G Simonsson

Publications and source records attributed to B G Simonsson.

At least 37 records · Page 2Linked to original sources
PubMed1983

Does atropine block antigen-induced contraction in canine bronchial rings? A preliminary report.

Isometric contractions recorded with a strain gauge, were elicited with cumulative doses of ascaris suum antigen on fresh canine bronchial rings from 8 dogs. Fifteen rings from 2 spontaneously sensitized dogs reacted with contractions to the antigen, while 11 rings from other dogs did not react. Seven sensitized rings were re-challenged after atropine, which significantly prevented the antigen from contracting these rings at a time when antigen contracted 3 non-atropinized, simultaneously tested rings from the same bronchi. Acetylcholine may play a part in the smooth-muscle contraction induced by antigen, or atropine may inhibit early activation of the "arachidonic acid cascade". The findings may be of interest in the interpretation of anti-muscarinic drugs as inhibitors of reflex cholinergic activity versus local anti-allergic effect.

Animals↗
PubMed1982

Bronchial reactivity, smoking, and alpha1-antitrypsin. A population-based study of middle-aged men.

We assessed bronchial reactivity to increasing doses of inhaled methacholine (MCH) in a population-based study on alpha1-antitrypsin. We compared 34 consecutive 48- to 50-yr-old heterozygous (Pi-MZ) men with 31 men of the same age with normal Pi phenotype (Pi-M) matched for smoking habits. There was no significant difference between control FEV1 or in MCH reactivity between the Pi-MZ and the Pi-M group. Twelve Pi-MZ subjects and 11 Pi-M subjects showed a fall of greater than or equal to 15% of FEV1 (PC 15%). Smokers showed increased sensitivity to MCH in both phenotype groups, although there was no significant difference in control FEV1 between the smoking and nonsmoking groups. Eleven smokers and ex-smokers, 5 with histories of asthma or sputum production, showed bronchial hyperreactivity, i.e., PC 15% FEV1, to 0.1% MCH or lower concentrations. Among nonsmokers there was 1 reactor and 1 hyperreactor. We conclude that heterozygous alpha1-antitrypsin deficiency (Pi-MZ) does not increase bronchial reactivity and that smoking does.

Bronchi↗
PubMed1982

Bronchial reactivity to methacholine in ten non-obstructive heavy smokers before and up to one year after cessation of smoking.

We studied non-specific bronchial reactivity to methacholine (MCh) before and during 1 year after cessation of smoking in four female and six male "smoke resistant" heavy cigarette smokers without severe respiratory symptoms or airways obstruction. The patients had smoked an average of 33 cigarettes a day since age 16. A standardized test of non-specific bronchial reactivity to methacholine was performed prior to cessation and 1 week, 1, 6 and 12 months after cessation of smoking proven by a decrease to normal COHb. Before cessation only two subjects showed a greater than or equal to 15% decrease of FEV1 after inhalation of 0.1% MCh which is compatible with bronchial hyperreactivity. Already 1 week after cessation there was a significant increase in FEV1 and VC to values around 100% of predicted. Bronchial reactivity was judged to decline after 1 month of non-smoking in four subjects but was unchanged in the others, and there was no statistically significant decrease of bronchial reactivity in the group of 10 after a 12-month smoke-free period.

Adult↗
PubMed1982

Piperazine-induced occupational asthma.

Asthmatic reactions were studied among some 130 factory workers who handled amines and other chemicals. Among present employees, we found 15 cases of asthma associated with occupational exposure to chemicals; among former employees there were at least 18. The inducing agent was judged to be piperazine in 29 persons and ethylenediamine (EDA) in three. The asthma was of the late or dual type; immediate reactions alone were to seen. No one had attacks of asthma before employment, and atopic subjects were not preferentially affected. Routine spirometry revealed airway obstruction in fewer than half of the recent cases. Tests of nonspecific bronchial reactivity with methacholine in six subjects with recent asthma showed hyperactivity in five, while tow subjects with earlier asthma did not have hyperactivity. Bronchial provocation tests with piperazine in one subject were positive both in the factory and in the laboratory. The level of piperazine was 1.2 mg/m3 time-weighted average (TWA) in a work place associated with induction of the asthmatic state, and 0.3 mg/m3 in a place connected with attacks in "sensitized" subjects.

Adult↗
PubMed1981

Drug-induced changes in airways obstruction reflected by forced expiratory flows and airway resistance measured with an oscillometric method using quiet breathing.

14 patients with partially reversible airways obstruction were studied with forced expiratory flows (FEV1, PEFR) and with airway resistance measured by an oscillometric method (Siregnost FD-5) before and after drug-induced changes in airways obstruction. 10 inhaled methacholine to induce bronchoconstriction, and 4 inhaled salbutamol and an additional dose of neosynephrine to induce bronchodilation. Intraindividual changes in resistance (Rosc) measured by the oscillometer with quiet breathing showed a fair significant correlation with changes in FEV1 (r = 0.54, p less than 0.05) and changes in PEFR measured by the Wright peak flow meter (r = 0.59, p less than 0.05). The present type of oscillator can be used for provocations starting from normal airway resistance but not for measures of treatment effects in markedly obstructive patients.

Adult↗
PubMed1981

Effects of angiotensin II and bradykinin on isolated human pulmonary arteries.

In vitro studies were performed on the contractile responses of 44 human segmental pulmonary artery specimens obtained from 26 patients undergoing thoracic surgery for pulmonary malignancies or bronchiectasis. Isometric changes in tension were recorded as cumulative dose-response curves in 14 arterial strips after angiotensin II. The angiotensin II-antagonist (Sar1, Ile8-)-angiotensin II demonstrated a competitive antagonism to angiotensin II. No changes of the resting tension occurred from a steady state in 10 specimens after bradykinin challenge. The relaxing effect of bradykinin was investigated after maximal contraction with either prostaglandin F2 alpha, histamine or norepinephrine in 23 specimens. Some relaxation could be obtained in 18, but total relaxation did not occur. We postulate the presence of specific angiotensin II-receptors mediating weak contraction and bradykinin-receptors mediating weak relaxation in isolated human pulmonary arteries.

Adult↗
PubMed1980

Cytological and cytogenetical analysis of thoracic duct lymph in patients with pulmonary carcinomas.

Seven patients with squamous cell carcinomas of the lung and nodular metastases underwent Daniels' biopsy and cannulation of the thoracic duct. Lymph specimens obtained by aspiration the day after catheter insertion were examined by cytologic and cytogenetical techniques, including chromosome banding methods. In five of the seven cases maligant cells could be detected by karyotype analysis, whereas standard cytologic examinations yielded no positive diagnoses. This indicates that chromosome analysis is applicable as a diagnostic tool in lymph fluid.

Carcinoma, Squamous Cell↗
PubMed1980

A dual action of histamine on isolated human pulmonary arteries.

Isometric tension changes in 22 isolated segmental human pulmonary arteries obtained from 17 patients at thoracic surgery were studied after histamine challenge. Cumulative dose-response contraction curves were constructed. A slight potentiation could be found with the H2 antagonist cimetidine, whereas the H1 blocker mepyramine moved the log dose-response curve for histamine to the right indicating competitive antagonism at specific receptors. When mepyramine was added after maximal contraction with histamine, a relaxation occurred that could be blocked by adding cimetidine prior to mepyramine. The in vitro tests reveal a dual action of histamine with a dominating H1 receptor mediated contraction, but with the possibility of relaxation via specific H2 receptors in human pulmonary arteries.

Cimetidine↗
PubMed1980

Adrenergic receptors and sympathetic agents in isolated human pulmonary arteries.

We tested the in vitro contractility of 88 segmental pulmonary arteries from 46 patients undergoing thoracic surgery. The vascular strips, taken from macroscopically healthy lung tissue, were devoid of spontaneous adrenergic tone. Cumulative dose-response curves with epinephrine and norepinephrine showed graded contraction. There was no significant difference between the two substances concerning mean maximal tension, threshold doses, ED50 or concentrations causing maximal contraction. Alpha-receptor blocking agents, phenoxybenzamine and indoramine, showed an inhibition of the contraction induced with both epinephrine and norepinephrine. Epinephrine in higher doses caused a dual response: contraction followed by relaxation. The latter was blocked by propranolol. Both isoproterenol and theophylline relaxed contracted vessels to some extent. Relaxation induced by isoproterenol could be blocked by propranolol. "Selective" beta2-stimulants such as terbutaline or salbutamol induced no relaxation. The results suggest the presence of alpha-receptors mediating constriction and possibly beta1-receptors mediating relaxation in human segmental arteries.

Adult↗