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A Schachar

Publications and source records attributed to A Schachar.

3 recordsLinked to original sources
PubMed1991

Prognostic importance of delayed Q-wave evolution 3 to 24 hours after initiation of thrombolytic therapy for acute myocardial infarction.

The timing of Q-wave evolution and its prognostic significance was studied in 201 patients who received thrombolytic therapy for a first acute myocardial infarction (AMI). One hundred forty-one patients (70%) had evidence of a Q-wave AMI within 3 hours of the initiation of thrombolytic therapy, 31 (16%) developed Q waves after 3 hours but before hospital discharge, and 29 (14%) were discharged with a non-Q-wave AMI. Laboratory indicators of myocardial damage and in-hospital morbidity and mortality were greater among patients with Q-wave AMIs than with non-Q-wave AMIs. When these indexes were examined with respect to the timing of Q-wave evolution, the prognosis of patients with delayed Q-wave development was similar to that of patients with non-Q-wave AMIs. Thus, compared to patients with early (less than or equal to 3 hours) Q-wave evolution, patients with delayed Q-wave evolution or with a non-Q-wave AMI had a smaller creatine kinase peak (mean 661 to 1,081 vs 1,251 to 1,541 IU; p = 0.005), better preservation of left ventricular function as measured by radionuclide ventriculography before discharge (mean +/- standard deviation 54 +/- 11% vs 47 +/- 13%; p less than 0.01), and a lower incidence of congestive heart failure at discharge (3 vs 15%; p = 0.02). In-hospital mortality was lower among patients with delayed Q-wave evolution or with a non-Q-wave AMI (5 of 141 vs 0 of 60; difference not significant).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1984

Thyrotropin-releasing hormone (TRH) improves survival in anaphylactic shock: a central effect mediated by the sympatho-adrenomedullary beta-adrenoceptive system.

Treatment with thyrotropin-releasing hormone (TRH) significantly improved survival following induction of fatal systemic anaphylaxis in mice. The protective effect was mediated centrally since survival was increased by intracerebroventricular (i.c.v.) administration of TRH at doses which had no effect when given systemically (5-25 micrograms). Acid-TRH, a deamidated metabolite of TRH which lacks hypophysiotropic influences, was as effective as TRH when administered i.c.v., but it was inactive following intravenous (i.v.) administration. The protective effect of TRH in anaphylaxis was reversed by treatments which diminished sympathetic outflow to the adrenal medulla, i.e. ganglionic blockade by chlorisondamine chloride or surgical denervation of the adrenal glands. Destruction of sympathetic nerve endings by the catecholamine neurotoxin 6-hydroxydopamine did not alter the response to TRH. Finally, selective blockade of beta-adrenoceptive sites by propranolol diminished the effect of TRH. Blockade of alpha-adrenoceptors by phentolamine or dopaminergic receptors by domperidone did not alter the protective effect of TRH in anaphylaxis. Collectively, these results indicate that the beneficial effect of TRH in anaphylactic shock involves central nervous system actions which are mediated peripherally through interaction of sympatho-adrenomedullary catecholamines with beta-adrenoceptive effectors. The possibility that TRH exerts its protective actions in shock by acting centrally to functionally antagonize the pathophysiologic effects of endogenous opiate peptides (endorphins) will be discussed.

Adrenal Medulla↗