Frequency-dependent Cardiac Electrophysiologic Effects of Tedisamil: Comparison With Quinidine and Sotalol.

BACKGROUND: Tedisamil is a potent bradycardiac/antiischemic drug known to lengthen cadiac repolarization by blocking various potassium channels. Recent in vivo experiments revealed that it is an antiarrhythmic agent. It was therefore of interest to compare the cellular electrophysiologic effects of tedisamil with those of quinidine and sotalol in isolated cardiac preparations.

Comparison of cefdinir and penicillin for the treatment of pediatric streptococcal pharyngitis.

This multicenter, randomized, controlled, investigator-masked study was performed to assess the efficacy and tolerability of cefdinir for the treatment of streptococcal pharyngitis. Children aged 1 through 12 years with signs and symptoms of pharyngitis and a positive result on a rapid screening test for Streptococcus pyogenes were randomly assigned to receive cefdinir 14 mg/kg QD, cefdinir 7 mg/kg BID, or penicillin V 10 mg/kg 4 times daily for 10 days. Seven hundred ninety-two patients were enrolled, and 682 were clinically and microbiologically assessable.

Targeted remodeling of human beta-globin promoter chromatin structure produces increased expression and decreased silencing.

The chromatin structure of the human beta-globin gene locus assumes a transcriptionally-active conformation in erythroid cells. One feature of this chromatin reorganization is the formation of DNase 1 hypersensitive sites in the regions of active globin gene promoters. This reorganization requires the globin locus control region and is associated with normal expression of the beta-like globin genes.

Solution assembly of the pseudo-high affinity and intermediate affinity interleukin-2 receptor complexes.

The high affinity interleukin-2 receptor is composed of three cell surface subunits, IL-2Ralpha, IL-2Rbeta, and IL-2Rgamma. Functional forms of the IL-2 receptor exist, however, that enlist only two of the three subunits. On activated T-cells, the alpha- and beta-subunits combine as a preformed heterodimer (the pseudo-high affinity receptor) that serves to capture IL-2.

Slow and Steady Wins The Race? Progress in the Development of Vectors for Gene Therapy of β-Thalassemia and Sickle Cell Disease.

The cloning of the human β-globin genes more than 20 years ago led to predictions that β-thalassemia and sickle cell disease would be among the first monogenic diseases to be successfully treated by gene replacement therapy. However, despite the worldwide enrollment of more than 3,000 patients in approved gene transfer protocols, none have involved therapy for these diseases. This has been due to several technical hurdles that need to be overcome before gene replacement therapy for β-thalassemia and sickle cell disease can become practical.

Molecular basis for effects of carcinogenic heavy metals on inducible gene expression.

Certain forms of the heavy metals arsenic and chromium are considered human carcinogens, although they are believed to act through very different mechanisms. Chromium(VI) is believed to act as a classic and mutagenic agent, and DNA/chromatin appears to be the principal target for its effects. In contrast, arsenic(III) is considered nongenotoxic, but is able to target specific cellular proteins, principally through sulfhydryl interactions.

Increasing metastatic potential is associated with induced chromosome 14 translocations in a previously nonmetastatic murine melanoma cell line.

The purpose of these studies was to demonstrate causal effects of abnormalities induced in mouse chromosome 14 on tumorigenicity and metastasis using the K-1735 murine melanoma cell line. Because anomalies in chromosome 14 have previously been associated with increases in metastatic potential, we induced chromosome 14 anomalies in a nonmetastatic K-1735 clone 10 cells initially containing two normal copies of chromosome 14 by treatment with mitomycin C. Clone 10-M1, in which a small population of cells (approximately 4%) contained translocations involving chromosome 14, was isolated and injected into athymic nude mice.

Can cancer cells transform normal host cells into malignant cells?

A human prostate tumour cell line, LNCaP C4-2, when injected into athymic male nude mice, produced tumours containing: (1) only human cancer cells similar to those injected; (2) only murine stromal cells containing abnormal chromosome constitutions; or (3) both human prostate cancer cells similar to those injected and the transformed murine stromal cells with altered chromosome constitutions. Karyotypic analysis of murine metaphases from all the host-derived tumours showed mostly pseudodiploid chromosome constitutions, with multiple copies (amplification) of mouse chromosome 15 and the absence of a typical Y chromosome. Fluorescence in situ hybridization analysis of these murine cells, using a biotin-labelled total human DNA painting probe, further demonstrated the absence of human DNA and the presence of only mouse metaphase and interphase cells in these transformed stromal cells.

A study of 5-day cefdinir treatment for streptococcal pharyngitis in children. Cefdinir Pediatric Pharyngitis Study Group.

Objective: To compare the safety and efficacy of a 5-day regimen of cefdinir with those a conventional 10-day regimen of penicillin V for the treatment of streptococcal pharyngitis in children.

Design: Investigator-blind, randomized controlled trial.

Setting: Primary care, ambulatory.

Differential Electrophysiologic Effects of Chronically Administered Amiodarone on Canine Purkinje Fibers versus Ventricular Muscle.

BACKGROUND: Acute and chronic treatment with amiodarone has been reported to cause different electrocardiographic changes in patients. The cellular electrophysiologic effects of chronic administration (50 mg/kg/day orally for 6 weeks) and acute superfusion (5 µM in the tissue bath) of amiodarone were therefore studied in dog cardiac ventricular muscle and Purkinje fibers using conventional microelectrode techniques. METHODS AND RESULTS: During stimulation at 1 Hz, chronic amiodarone treatment lengthened the ventricular muscle action potential duration (APD) from 227.

Myoelectric activity and absorptive capacity of rat small intestinal isografts.

The effect of transplantation on small intestinal absorption, digestive capacity, myoelectric activity, and morphology was assessed in inbred Lewis rats. Electrodes were sutured to the duodenum and isografted jejunoileum or to the native jejunoileum in controls. The frequency of migrating myoelectric complexes (MMCs) in the duodenum was 3.

The cellular electrophysiological effects of tedisamil in human atrial and ventricular fibers.

The cellular electrophysiological effects of 1 microM tedisamil (KC 8857) were studied in human atrial and ventricular fibers. Conventional microelectrode technique was applied to record the transmembrane action potentials at stimulation frequency of 100 per min and 37 degrees C. Tedisamil lengthened action potential duration (APD) more in atrial than in ventricular muscle fibers; prolongation of APD90 was 28.

Comparison of the effects of restacorin and flecainide on various cardiac transmembrane potassium currents.

The effect of restacorin (5 microM) and flecainide (5 microM) on the transmembrane ionic currents was compared in dog and rabbit ventricular muscle by applying the conventional microelectrode and patch-clamp techniques. Neither restacorin nor flecainide influenced significantly the ATP-sensitive and inward rectifier potassium currents. Flecainide moderately decreased the amplitude of the transient outward current while restacorin did not change this current.

Electrophysiological effects of tiracizin and its metabolites in dog cardiac Purkinje fibers.

1. Conventional microelectrode technique was used to study the effects of tiracizin and its two main metabolites on the action potential parameters in dog cardiac Purkinje fibers. 2.

Laboratory study on occult gastrointestinal bleedings: differential diagnostic method for the parallel study of intact and fragmented hemoglobin.

The authors produced various degradation products of human hemoglobin. With the aid of immune sera raised against native hemoglobin and their fragments, we examined the antigenicity of the intact molecule and fragments as well as the specificity and reactivity of the immune sera used. Since conventional guaiac-type reactions make no distinction between the different hemoglobin molecules and the methods described in recent years' publications only with immune sera raised against native intact hemoglobin, the demonstration of occult fecal blood has not reached the desired rate of efficacy in clinical practice.

Electrophysiologic effects of detajmium on isolated dog cardiac ventricular and Purkinje fibers.

We studied the electrophysiologic effects of the antiarrhythmic compound detajmium (Tachmalcor) on isolated dog and rabbit cardiac preparations, applying the conventional intracellular microelectrode techniques. In dog ventricular muscle fibers (37 degrees C, stimulation frequency 1 Hz), 1 microM detajmium did not change resting potential (RP), action potential amplitude (APA), AP duration measured at 90% of repolarization (APD90), or effective refractory period (ERP) significantly, but reduced maximum rate of depolarization (Vmax) significantly from 236.7 +/- 28.

Double immunochemical screening test (hemoglobin and albumin) for the detection of occult intestinal bleeding.

The authors have developed a combined electrophoretic-immunoprecipitation technique suitable for the simultaneous demonstration of two blood proteins, i.e., hemoglobin and albumin, in the feces.

Clinico-bacteriological examination of Betadine skin disinfectant fluid and liquid soap in hospitalized patients and hospital employees.

The effectivity of Betadine skin and mucosa disinfectant solution and Betadine hand disinfectant soap (MUNDIPHARMA A. G. and EGIS Pharmaceuticals has been examined in hospitalized patients and hospital employees.

Effect of a prolonged-release formulation of N-methionyl bovine somatotropin (sometribove) on milk fat.

Nine Holstein cows were injected bi-weekly with a prolonged-release formulation of N-methionyl bST, and 9 cows were injected with excipient. Intramuscular injections began at 60 +/- 3 d postpartum and continued at 14-d intervals for the full lactation. Administration of bST increased production of milk, total fat, and all milk fat components measured.

Effect of a prolonged-release formation of N-methionyl bovine somatotropin (sometribove) on milk composition.

Forty Holstein cows received bi-weekly injections of prolonged-release formulation of bST, and 39 received bi-weekly injections of excipient, in a study to evaluate the effects of long-term bST administration on milk composition and component production. Injections began at 60 +/- 3 d postpartum. Administration of bST increased production of milk and of all measured components.