Tiapamil--a new calcium antagonist.

Calcium antagonists are an important new modality in cardiovascular therapy. Tiapamil, a congener of verapamil, is undergoing clinical and laboratory evaluation. We have undertaken experimental studies on the anti-arrhythmic properties of tiapamil, and on the intravenous use of this agent in patients with acute myocardial infarction.

Tiapamil, a new calcium antagonist: hemodynamic effects in patients with acute myocardial infarction.

The afterload reduction and myocardial oxygen sparing that results after administration of calcium antagonists suggests a possible role for these drugs in intervention after onset of acute myocardial infarction, but their use in this setting is limited by the possibility that left ventricular failure will develop. Tiapamil is a new verapamil congener. The hemodynamic effects of this drug (1 mg/kg followed by 25 micrograms/kg/min over 36 hr) were studied in 30 patients randomly assigned in a double-blind manner to a tiapamil or control group within 12 hr of the onset of acute myocardial infarction as diagnosed by Swan-Ganz catheterization and gated blood pool scans.

Effect of ketanserin on phenylephrine-dependent changes in splanchnic hemodynamics and systemic blood pressure in healthy subjects.

We studied the effect of ketanserin on basal status and phenylephrine-dependent changes in arterial blood pressure and splanchnic hemodynamics in seven healthy subjects. The drug was administered as an intravenous bolus of 10 mg followed by infusion of 4 mg/h. After a basal period of saline or ketanserin infusion, phenylephrine was infused at a constant rate in a fixed dose sequence of 1, 2, and 3 micrograms/kg/min.

Release of vitamin B12 from carrier erythrocytes in vitro.

Resealed erythrocyte ghosts (carrier erythrocytes) are potential in vivo carriers for exogenous enzymes or drugs, but data on carrier erythrocyte survival and clearance rate in humans are not available. We have measured the in vitro efflux of vitamin B12 encapsulated in human red cell by hypo-osmotic dialysis, as a preliminary for its use as a marker for in vivo human studies. Vitamin B12 was encapsulated into erythrocytes at a relative incorporation efficiency of 60%.

Effect of cianopramine, a tricyclic antidepressant, on platelet serotonin uptake and peripheral adrenergic function.

Cianopramine, a new tricyclic antidepressant, is a potent inhibitor of neuronal serotonin (5-HT) uptake in animals. We studied the effect of cianopramine on 5-HT uptake (ex vivo) in platelets and on peripheral neuronal adrenergic function in catecholamine pressure response tests in normal subjects. The inhibition of 14C-labeled 5-HT uptake into platelets was 57% +/- 12% 2 hr after 0.

Hemodynamic effects of sublingual nifedipine in acute myocardial infarction.

Twenty-six patients with acute myocardial infarction (mean delay time 6 hours after onset of symptoms) were randomized to control or nifedipine treatment (10 mg sublingually, followed by 10 mg every 6 hours for a total of 24 hours). Nifedipine reduced arterial blood pressure from 127/78 to 115/70 mm Hg at 30 minutes (p less than 0.001) and continued to reduce the blood pressure significantly for 12 to 18 hours.

The effect of a new specific alpha-amylase inhibitor on post-prandial glucose and insulin excursions in normal subjects and Type 2 (non-insulin-dependent) diabetic patients.

Trestatin (Ro 9-0154), a new specific alpha-amylase inhibitor of microbial origin, was tested in six normal subjects and seven Type 2 (non-insulin-dependent) diabetic patients. In normal subjects the maximal increases in blood glucose following a 115-g starch meal were 2.19 +/- 0.

[Accidental fatal formaldehyde poisoning].

A previously healthy man accidentally swallowed 20 to 50 ml of Formalin (25%). Relevant clinical findings after the accident were: severe metabolic acidosis, severe disseminated intravascular coagulation and renal failure. He died 7 hours after formaldehyde ingestion-presumably from toxic pulmonary oedema.

[Pharmacokinetics and acute signs of cardiac toxicity during doxorubicin therapy].

Doxorubicin (Adriamycin) has shown impressive activity in the treatment of a broad spectrum of malignant tumours. Chronic irreversible cardiac myopathy is the usual cumulative dose-limiting toxicity with this anthracycline antibiotic. In this study acute cardiac reactions following doxorubicin infusions (60 mg/m2) were registered by means of ECG Holter monitoring and measurement of systolic time intervals.

Cardiocirculatory effects of moclobemide (Ro 11-1163), a new reversible, a short-acting MAO-inhibitor with preferential type A inhibition, in healthy volunteers and depressive patients.

The benzamide-derivative moclobemide (Ro 11-1163) is a new short-acting, reversible MAO-inhibitor, preferentially affecting Type A MAO, which is, being developed as an antidepressant agent. The effect of moclobemide on heart rate, blood pressure, electrocardiographic and systolic time intervals was assessed in eight healthy volunteers and seven depressive patients. The volunteers received single doses of 100 mg, 150 mg and placebo in radomized single-blind order.

Accidental ingestion of NaF tablets by children--report of a poison control center and one case.

Accidental ingestion by children of NaF tablets for caries prophylaxis is a frequent event. However, our own experience from the Poison Information Centre in Vienna and reports from other centers show that these accidents usually do not present a serious risk. The mechanism of fluoride toxicity and symptoms of poisoning are briefly reviewed.

The role of serine hydroxymethyltransferase in cell proliferation: DNA synthesis from serine following mitogenic stimulation of lymphocytes.

It is shown that the time-course of incorporation of radioactivity from [3-14C]serine into nucleic acids parallels DNA synthesis following mitogenic stimulation of human peripheral blood lymphocytes by phytohaemagglutinin (PHA). The activity of serine hydroxymethyltransferase was elevated about four-fold in PHA-stimulated lymphocytes compared to that in unstimulated control cells. It is suggested that lymphocytes, in common with other proliferating cell systems, may synthesize serine de novo for utilization in pathways of nucleotide biosynthesis following mitogenic stimulation.

Quenching of two-photon fluorescence and stimulated anti-Stokes emission in rhodamine solutions.

Two-photon fluorescence (TPF) has been excited in different solutions of rhodamine 6G and rhodamine B with single 30-psec pulses from a Nd:YAG laser at 1.06 microm. Up to incident intensities of 6 x 10(28)photons cm(-2) sec(-1) the TPF intensity showed a quadratic dependence on the photon flux.

Power requirements and resolution of real-time holograms in saturable absorbers and absorbing liquids.

Diffraction gratings have been induced in absorbing liquids and saturable glasses with a ruby laser. The mechanism for the production of the gratings has been discussed. The diffraction efficiency and the resolving power of the materials has been measured and found to agree with calculations based on the models of a thermal phase grating and a grating produced by saturable absorption.

Measurement of Length Shifts down to 10(-3) A with a Two-Mode Laser.

The frequency of one axial mode of a two-mode He-Ne laser is tuned by mirror displacement independently from the other mode if a third mirror is added to the usual two laser mirrors. The frequency shift is proportional to the mirror displacement and can be detected with high sensitivity by observing the beat frequency with the other axial mode. The sensitivity of such a two-mode laser with a coupled resonator for measurements of small length shifts has been tested.