Flecainide versus quinidine in the prevention of paroxysms of atrial fibrillation

We compared the efficacy of flecainide versus quinidine in preventing paroxysms of atrial fibrillation in a randomized open crossover study. Twenty-six patients with weekly attacks of atrial fibrillation during the last 3 months, objectified by 24-h holter monitoring or 12-lead electrocardiogram (ECG) were treated for a period of 3 months with flecainide 100 mg b.i.d. or quinidine 500 mg b.i.d. Efficacy was assessed by 24-h holter monitoring and a questionnaire at the end of each month. Dosage was adjusted to flecainide 100 mg t.i.d. or quinidine 500 mg t.i.d. if patients still had symptomatic paroxysms of atrial fibrillation according to a questionnaire or on holter monitoring. In 46% of the patients, flecainide 100 mg b.i.d. caused total abolition of supraventricular tachycardia; after dose adjustment it caused 50% total abolition. For quinidine, the figures are 16% (p less than 0.05) and 32% (NS), respectively. Side effects occurred with flecainide only after dose adjustment (23%), but on quinidine they occurred before (8%) and after dose adjustment (20%). We conclude that flecainide suppresses paroxysms of atrial fibrillation significantly more often as compared with quinidine in the lower dosage regimen. Optimal treatment dosage of flecainide is 100 mg b.i.d. After quinidine dose adjustment, the difference in efficacy is no longer significant. However, side effects necessitating discontinuation of quinidine developed in 20% of the patients as compared to none in patients treated with flecainide 100 mg b.i.d.     

Zinc, calcium, and magnesium metabolism: effects on plasmacytomas in Balb/c mice

The effects of different amounts of dietary zinc on the Zn absorption rate and on Zn, calcium and magnesium concentrations in tissues of MOPC 104E tumor-bearing Balb/c mice were determined. The Zn absorption rate was inversely related to the amounts of Zn in their diets and was lower than that of nontumor-bearing control mice fed a laboratory mice chow. Zn concentrations of tumor-bearing mice were also low compared with control mice but tumor Zn concentrations, regardless of the concentrations of Zn in the diets, were higher than those of normal tissues of the host other than the pancreas. Ca concentrations in tumor and tissues of tumor-bearing mice were higher than in control animals but Mg concentrations in tissues of tumor-bearing mice appeared to be similar to those of control mice. Results suggest that tumor-bearing mice have a lower intestinal Zn absorption capacity and a higher Zn uptake rate causing other tissues to become hypozincemic and hypercalcemic.     

PharmaTrend as a management tool: capturing workload data

Several methods of collecting workload data for use in PharmaTrend, a computerized pharmacy management information system, are described. Although the number of indicators produced by PharmaTrend is limited by the input of the user, the integrity of the indicators that are produced is not compromised; this allows the user to implement PharmaTrend on a limited scale, such as for workload only. Workload data that can be used in PharmaTrend are collected routinely by most pharmacies. Many activities are already recorded in logs and other noncomputerized sources. The aid of members of the pharmacy department and other departments may be enlisted in collecting these data. Self-reporting through time sheets and cards can also be used to obtain data on the distribution of work hours. Recording is simplified if employees are told to record only exceptions to their usual job responsibilities. The PharmaTrend manual contains detailed definitions of the workload categories, but simpler and more practical definitions may have to be used. A computer spreadsheet program should probably be used for compiling data if they are collected from several sources; this will facilitate entry into PharmaTrend. Simple methods are available for capturing workload data for input into the PharmaTrend program.     

Fatal and non-fatal stingray envenomation

A fatality occurred in a previously healthy 12-year-old boy after a penetrating chest injury from a stingray barb. The injury occurred under freak circumstances. Death was a result of cardiac tamponade which was secondary to venom-induced, localized myocardial necrosis and spontaneous perforation, six days after the direct penetration of the right ventricle by the barb. Three other cases of less serious stingray envenomation are described which illustrate the significant localized morbidity that may occur without immediate wound exploration and toilet after adequate anaesthesia. We also report a study of a series of 100 minor stingray envenomations which, when treated, resulted in no morbidity. It is possible that local infiltration with 1% plain lignocaine may have a direct counteraction against stingray venom that remains in the wound area. Stingray venom has insidious, but powerful, localized tissue necrosing properties in humans.     

Phase I study of high-dose cytosine arabinoside and etoposide in patients with advanced malignancies

Summary Cytosine arabinsodie (ara-C) and etoposide (VP-16) display synergy in the laboratory. Twenty-six patients participated in a phase I study of high-dose ara-C in combination with VP-16. The dose of VP-16 was held constant at 50 mg/m² as an intermittent infusion over 33 h; escalating doses of ara-C were given as infusions during hours 9–12 and 21–24. Myelosuppression was the dose-limiting toxicity and occurred with doses considerably less than those expected from studies of the two drugs as single agents. The suggested initial doses for phase II trials with this schedule are 750 mg/m²×2 doses of ara-C and 50 mg/m² of VP-16. Nonhematologic toxicity was minimal; therefore, further dose escalation is feasible in patients in whom myelosuppression is acceptable.Supported in part by grants from the National Cancer Institute (CA-12197 and CA-09422) and the American Cancer Society CF-85-182     

4-Aminopyridine affects synaptosomal protein phosphorylation in rat hippocampal slices

Rat brain hippocampal slices were incubated with or without the convulsant 4-aminopyridine (4-AP). From these slices a crude mitochondrial/synaptosomal membrane fraction was prepared and analyzed for endogenous protein phosphorylation. 4-AP (10(-5) M) stimulated the phosphorylation of a 50 kDa protein by 86%. The phosphorylation of this 50 kDa protein is Ca2+/calmodulin-dependent and we suggest that this protein is the lower molecular weight subunit of Ca2+/calmodulin-dependent protein kinase II (CaMK II).