Search PubMed⌕ Search

Biomedical subjects

J Lang

Publications and source records attributed to J Lang.

603 records · Page 34Linked to original sources
PubMedDate not supplied

Safety and immunogenicity of a new equine tetanus immunoglobulin associated with tetanus-diphtheria vaccine.

In a single-center double-blind, randomized trial in West Africa, we evaluated the safety and immunogenicity of a new pasteurized, pepsin-digested equine tetanus immunoglobulin (heat-treated equine tetanus immunoglobulin [HT-ETIG]) in the post-exposure prophylaxis of tetanus compared with the reference product, equine tetanus immunoglobulin (ETIG). A total of 134 adults presenting to Garoua Hospital, Cameroon with a tetanus-prone wound were randomized to receive a 3,000 international units (IU) intramuscular injection (deltoid) of either HT-ETIG or ETIG, simultaneously with a tetanus-diphtheria vaccine. No serious adverse reactions were reported. The incidences of local and systemic reactions were similar in the two groups. Repeated measures of equine tetanus-antibody levels measured from Day 0 to Day 28 showed that titers were significantly higher in the HT-ETIG group (P = 0.017). At Day 7, a higher percentage of subjects in the HT-ETIG group had equine antibody levels > or = 0.1 IU/ml (80.4% versus 37.9%; P < 0.0001). No cases of tetanus occurred during the follow-up, attesting to the efficacy of the combined prophylactic treatment.

Adolescent↗
PubMedDate not supplied

Frequency- and time-dependent depression of ventricular distal conduction by two novel antiarrhythmic drugs, cibenzoline and flecainide.

The effects of two novel antiarrhythmic drugs, cibenzoline and flecainide, known to exert potent inhibitory effects on sodium channel, were investigated on intraventricular conduction in anaesthetized, closed-chest dogs. During this study, in which the heart was electrically stimulated, the pacing period was gradually reduced in the 500-200 msec range, and the pacing rate was abruptly altered (2 sec) or sustained (8 to 10 sec) in order to study the possible frequency- and time-dependency of the depression of conduction. In addition to the electrocardiogram, the conduction time was recorded in the ventricular contractile tissue between an electrode advanced to the apex and the pacing electrode positioned near the base. Effective refractory period (ERP) was concurrently measured according to the extrastimulus method, and the monophasic action potential (MAP) recorded. The drugs were infused at a rate of 0.2 mg/kg/min over a 10 min period after a 4.0 mg/kg loading dose. Conduction time was lengthened by approximately 50% at low frequencies and 100% at high frequencies. Widening of the ORS complexes paralleled this lengthening, whereas the drugs tended only to prolong ERP, without preventing its shortening induced by acceleration. Cardiac disorders were aggravated when high pacing rates were maintained for 8 to 10 sec.

Action Potentials↗
PubMedDate not supplied

Modification of atrioventricular conduction under the combined influence of a cardiac glycoside and a calcium antagonist in the dog.

Conduction disorders may be logically expected from the digoxin-verapamil association, since each of these drugs is known to increase conduction time (CT) and effective refractory period (ERP) in the atrioventricular (AV) node. When AV conduction is considerably depressed by verapamil (1.27 mg/kg over 90 min) in the absence of vagal tone, digoxin, infused at 1 microgram/kg/min rate over 40 min, elicits a progressive but incomplete regression of the verapamil effects, as does hypercalcaemia up to 5.5 mmol/l. Infused at the 2.5 microgram/kg/min rate over 20 min, its antagonistic effects, like those of hypercalcaemia exceeding 5.5 mmol/l, are less and less marked and even replaced by a certain synergism. When AV conduction is considerably depressed by digoxin (i.v. injection of 40 micrograms/kg) under high vagal tone, verapamil (twice 0.2 mg/kg) does not aggravate this depression and even attenuates it, this attenuation being however more significant on ERP than CT in the AV node. Consequently, as a rule, the interaction does not lead to block, since the maximum action of one drug is associated with the reduction in the action of the other or even the conversion of synergism into antagonism.

Animals↗
PubMedDate not supplied

Vagal role in potentiation by Ca2+ ions of the action of cardiac glycosides on the atrial specialised tissue.

The combined effects of digoxin and hypercalcaemia were studied in the canine heart in situ on the sinoatrial (SA) and atrioventricular (AV) nodes. Measurements were made of heart rate, of conduction time in the AV node by the endocavitory recording of the His bundle potentials, and of the effective refractory period of this node by the extrastimulus method. In the presence of acetylcholine released by vagal endings or infused into the coronary blood, an increase in plasma calcium concentration from 2.50 to 4.60 mmol/l after a 80 micrograms/kg dose of digoxin considerably depressed conduction in the AV node and automatism in the SA node. In the absence of acetylcholine, no bradycardia occurred under the influence of digoxin alone or digoxin and hypercalcaemia, and hypercalcemia enhanced to a lesser extent digoxin-induced depression of conduction in the AV node. These results evidence a potentiation by acetylcholine of the combined effects of digoxin and hypercalcaemia on the SA and AV nodes.

Acetylcholine↗
PubMedDate not supplied

Influence of the restoration of vagal tone by intracisternal injection of dextromoramide on the cardiac effects of the antiarrhythmic drugs.

The effects of four antiarrhythmic drugs, quinidine, procainamide, amiodarone and verapamil were studied on sinus rate, conduction time and, when possible, effective refractory period (ERP) in atrioventricular node (AV node), and finally atrial muscle ERP. This study was made under two types of conditions, vagal tone being absent or present after restoration in the anesthetized dog by a new technique, the intracisternal injection of dextromoramide. Quinidine and procainamide which tend to slow down sinus rate and conduction in the former case accelerate them considerably in the latter by opposing the effects of acetylcholine released by vagal endings. The prolongation of atrial ERP also induced by these drugs results from both this process and their own capacity. Amiodarone and verapamil, usually responsible for bradycardia, notable delay in AV node conduction and lengthening of AV node ERP are, however, liable to elicit opposite effects, especially amiodarone when vagal tone is very high. The reduction of vagal influence is, in the case of these drugs, the only factor in the prolongation of atrial ERP. In any case, the response of both specialized and common tissue of the heart to antiarrhythmic drugs should not be interpreted unless the degree of vagal tone is known.

Amiodarone↗
PubMedDate not supplied

Nasopharyngeal carcinoma--the Irish experience.

Ten new cases of nasopharyngeal carcinoma were diagnosed at our unit during a recent twelve month period. An evaluation of these cases is presented. This stimulated an examination of the national data for the years 1981-1990 and it was discovered that 69 cases were diagnosed in that period. A chart review was performed of the patients with nasopharyngeal carcinoma that were treated at St. Lukes Hospital 10 years previously and compared to the 10 recently diagnosed patients. This data highlights: the young age at which this tumour can occur; that there has been no improvement in the early detection of these neoplasms and the importance of an ENT assessment for patients presenting with cervical lymphadenopathy, persisting middle ear effusion or atypical headaches.

Adolescent↗