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Biomedical subjects

V Torres

Publications and source records attributed to V Torres.

At least 73 records · Page 4Linked to original sources
PubMed1984

Antiarrhythmic action of bethanidine.

Studies were performed in 20 patients with symptomatic ventricular tachycardia (VT) to determine the efficacy of bethanidine compared with procainamide in preventing VT induced by programmed electrical stimulation. Before administering bethanidine, 5 to 10 mg/kg, the patients received 15 mg of protriptyline orally 24 and 2 hours before electrophysiologic studies to prevent the orthostatic hypotensive effects of bethanidine. Sustained VT (VT not spontaneously stopping) was induced in 8 and nonsustained VT (10 beats or more, terminating spontaneously) was induced in 4 patients. Bethanidine, 5 mg/kg, protected in 7 patients, and 10 mg/kg protected 1 additional patient. Procainamide, 1,000 and 1,500 mg intravenously, protected 8 of 16 patients. Bethanidine prevented VT induction in 50% of the patients not protected by procainamide. Bethanidine facilitated VT induction in 3 patients, while procainamide facilitated VT induction in 1 patient. Four patients with symptomatic VT have received bethanidine therapy for an average of 11 +/- 1.3 months, without clinical recurrence of their VT. Concomitant administration of protriptyline attenuated the acute hemodynamic changes caused by bethanidine and chronic combined therapy of protriptyline and bethanidine abolished the severe orthostatic changes in blood pressure caused by bethanidine. These studies show that bethanidine is effective in preventing VT induction and, thus, its use may not be restricted only to cases of primary ventricular fibrillation.

Bethanidine↗
PubMed1984

Intravenous quinidine by intermittent bolus for electrophysiologic studies in patients with ventricular tachycardia.

The safety and efficacy of intravenous quinidine gluconate, using intermittent boluses of 80 mg/cc every 5 minutes to a total dose of 800 mg, was evaluated in 61 patients referred for electrophysiologic studies (EPS). Patients were referred because of out-of-hospital cardiac arrest (12), symptomatic ventricular tachycardia (VT) (24), asymptomatic VT (18), syncope of unknown origin (6), and supraventricular arrhythmias (1). Clinical heart failure was present in 74% of patients, with a mean ejection fraction of 45 +/- 3 for all patients. Quinidine prevented VT induction in 78% of patients at a mean dose of 9.6 mg/kg and facilitated VT induction in 7% of patients. Quinidine failed to decrease mean arterial pressure in 14 patients, and in the remaining 47 patients arterial pressure decreased by 16%. Six patients had hemodynamically significant hypotension. Two patients had hypotension severe enough to require saline administration, while four had hypotension not needing fluid replacement. Sixteen percent of patients experienced other side effects. Quinidine can be administered safely by intermittent infusion and is effective in preventing programmed stimulation induction of VT. Carefully monitored, intravenous intermittent bolus administration of quinidine should be utilized more frequently in EPS, since significant adverse side effects are infrequent.

Adult↗
PubMed1984

The effect of bepridil, verapamil, and quinidine in the prevention of ventricular tachycardia induced by programmed electrical stimulation in the digitalized dog.

Bepridil, a new antianginal agent, has calcium channel-blocking activity and antiarrhythmic properties. To test the efficacy of bepridil as an antidysrhythmic agent, we looked at its effect on the induction of ventricular tachycardia (VT) in dogs, utilizing programmed electrical stimulation (PES). Incremental doses of bepridil up to 20 mg/kg were given to five nondigitalized dogs and verapamil up to 20 mg, and PES was performed at each dose. Both drugs were not found to facilitate arrhythmia induction. Seventeen dogs were chronically digitalized and following digitalization, VT could be induced in all animals by PES. Six dogs were given bepridil and PES was reperformed at each dose. An average of 1.8 mg/kg was found to protect against induction of VT. Five dogs received verapamil and none was protected (all had VT induced), while five of six dogs given quinidine were protected at an average dose of 15.4 mg/kg. Bepridil produced a significant decrease in heart rate. A significant correlation was found at the effective antiarrhythmic dose of bepridil between percentage change in the effective refractory period for the first extrastimulus (ERP S2) and QTc (r = 0.96), suggesting that a parallel and homogeneous prolongation in repolarization and refractoriness is essential for the antiarrhythmic effect of bepridil. Bepridil is thus an effective antiarrhythmic agent that affords protection against induction of VT, and this action is similar to the conventional class I antiarrhythmic agent, quinidine, while lacking in another calcium channel blocker, verapamil.

Animals↗
PubMed1977

[EMG syndrome. Review apropo of 2 cases].

Two cases of EMG syndrome are reported (exomphalos, macroglossia, gigantism). One of them died some hours after the birth. A review of clinical findings, pathogenesis and evolution is presented. Only 60 cases of this rare disease are reported in the world literature.

Abnormalities, Multiple↗
PubMedDate not supplied

[Helical CT and perfusion scintigraphy: diagnosis of pulmonary embolus in the clinical practice].

UNLABELLED: The purpose of this study was to compare helical CT with lung perfusion scintigraphy (LPS) as the initial investigations of patients with suspected pulmonary embolism (PE). PATIENTS AND METHOD: A total of 54 patients with clinically suspected acute PE were studied retrospectively. Each patient was assigned a pretest clinical probability of acute PE (very likely, 90%; possible, 50%; unlikely, 10%). Within 72 hours of presentation, patients underwent LPS and contrast material-enhanced helical CT. Perfusion LS was classified following the PISAPED criteria as normal or near normal; abnormal consistent with PE or abnormal not consistent with PE. Helical CT studies were categorized as positive for PE, negative for PE or non-diagnostic. The standard reference was a consensus based on LS, helical CT and clinical outcome. RESULTS: In 38 of the 54 patients, the results of LS a hCT were concordant, 13 with PE and 25 without. There were 4 indeterminate hCT. In 12 patients LS and hCT were discordant. There were 4 LS false negative; 2 with parenchyma damage and 2 chronic PE. There were 5 LS false negative; 3 extrinsic vascular compressions and one low clinical probability. There was 1 hCT false positive because of breathing artifact and 2 false negatives because of subsegmental emboli. CONCLUSION: Accurate diagnosis of acute PE is possible combining perfusion scanning and clinical probability. Helical CT has added information in patients with discordant clinical probability and perfusion lung scan results. Helical CT demonstrated lesions other than PE considered responsible for the patient's symptoms, but it was insensitive to embolism of subsegmental branches.

Adult↗
PubMedDate not supplied

[Inhibition of Mucor rouxii growth by synthetic substances].

Mucor rouxii cells were used to examine the possible antimycotic activities of four substances: phenolamines, phenylendiamine and quinone. These substances are original structures recently synthesized. Assays in plates showed that 10(-2) M of phenolamines and phenylendiamines give rise to halos of growth inhibition. Assays in liquid media using 10(-4) M of substances showed 100% inhibition of spore germination. Specifically, the phenylendiamine showed 49% inhibition on development of mycelium. In these cells the calcofluor distribution changes, suggesting alterations in cell wall. No inhibition of growth was found using the quinone. The activity for substances were evaluated using standard antifungal benomyl. On this basis, the substance phenylendiamine it is an antimycotic active. The mechanism of action is not presently known.

Aniline Compounds↗
PubMedDate not supplied

Cytology of fine needle aspiration biopsy of primary breast rhabdomyosarcoma in an adolescent girl.

A bilateral breast tumor in an 11-year-old girl was diagnosed as a malignant mesenchymal neoplasm by fine needle aspiration biopsy, and its muscular origin was suggested. An immunoperoxidase stain for the demonstration of intracellular myoglobin in destained cytologic aspirates exhibited a positive reaction of variable intensity in some of the undifferentiated round cells and in the more mature bipolar sarcomatous elements. These findings were confirmed in the histologic sections of the excised tissue. Needle aspiration is helpful in these rare cases of primary breast rhabdomyosarcoma, which often present with a solid, undifferentiated histologic pattern in this age group. In addition to the cytologic characteristics, the possibility of detecting muscle antigens as markers for these embryonal small cells, even in previously stained slides, provides a successful method for defining the specific type of sarcoma.

Biopsy, Needle↗