Alteration of Human Placental Vascular Tone by Antiarrhythmic Medications In Vitro

Antiarrhythmic and Placental Vessels. Introduction : Antiarrhythmic medications are commonly used during pregnancy for treatment of maternal or fetal arrhythmias, but little is known about their effect on human placental vascular tone and, consequently, placental blood flow. The objective of this study was to evaluate the tone responses caused by antiarrhythmic medications in human placental vessels from normal term pregnancies in vitro.
Methods and Results : Isolated human placental arteries and veins from uncomplicated term pregnancies incubated in Krebs'-bicarbonate under 5% oxygen/5% carbon dioxide/balance nitrogen (PO₂ 35 to 38 torr) were exposed to cumulative doses of quinidine, procainamide, lidocaine, flecainide, propranolol, amiodarone, verapamil, digoxin, and adenosine after submaximal contraction with 5-hydroxytryptamine. The study was conducted both in the presence and absence of endothelium. The addition of the tested medications caused a significant, dose-dependent relaxation of human placental arteries and veins except for adenosine, which induced a sustained, dose-dependent contraction of human placental vessels regardless of the presence or absence of tone. Removal of the endothelium did not alter these responses.
Conclusions : Based on these results, the medications tested should have no decremental effect on placental blood flow, with the possible exception of adenosine, which causes significant. dosedependent contraction of human placental vessels in vitro. Should similar contraction be present in vivo, it may have an adverse effect on the fetus when administering adenosine to pregnant women at term or during labor.     

Telemetry of Programmed and Measured Data in Pacing System Evaluation and Follow-up

Telemetry of programmed and measured data is an important feature of many pacemakers currently used in clinical practice. The ability to receive non-invasive data from the implanted device constitutes a major advantage for the long-term follow-up of the patients and of device performance. There are numerous types of data retrievable via telemetry: parameters of device characteristics (output, battery longevity, impedance, etc), event recorders or counters, event markers, and endocardial electrograms. Ideally, this information should be beneficial in the longitudinal surveilance of modern pacemakers.     

Molecular Interactions between the HSV-1 Capsid Proteins as Measured by the Yeast Two-Hybrid System

HSV-1 B capsids are composed of seven major proteins, designated VP5, VP19C, 21, 22a, VP23, VP24, and VP26. VP indicates that the capsid protein is also a component of the infectious virion. Capsid proteins 21, 22a, and VP24 are specified by a single open reading frame (UL26) that encodes 635 amino acids. An objective of the work in our laboratory is to identify and map interactions among and between capsid proteins. In the present studies we employed the yeast GAL4 two-hybrid system developed by Fields and his colleagues (Nature240, 245–246 (1989)) for this purpose. DNA corresponding to the capsid open reading frames was derived as a PCR product and fused to sequences of the GAL4 activation and DNA binding domains. Using this system each of the capsid proteins has been tested for interactions with all of the other capsid proteins. Three interactions have been identified: a relatively strong self-interaction between 22a molecules (residues 307–635 of UL26), bimolecular interactions between 22a and VP5, and another between VP19C and VP23. The interactions were detected by the expression of β-galactosidase enzyme activity, and yielded 289, 86, and 63 units of enzyme activity, respectively. For the 22a self-interaction, elimination of residues 611–635 resulted in an approximately twofold decrease in enzyme activity. The C-terminal 25 amino acids of 22a were also essential for the bimolecular interaction between 22a and VP5.     

Impact of Nutrients on Cellular Lipid Peroxidation and Antioxidant Defense System

A symposium entitled Impact of Nutrients on Cellular Lipid Peroxidationand Antioxidant Defense System was held at the 33rd Annual Meetingof the Society of Toxicology (SOT) at the Loews Anatole Hotelin Dallas, Texas. The symposium was sponsored by the Food SafetySpecialty Section and focused on the role of particular nutrientsin cellular lipid peroxidation and antioxidant defense system.Emphasis was placed on defining underlying mechanisms for damageand protection, as well as potential ramification in human healthissues. The following are extractions of some of the highlightsfrom each presentation.     

The Use of Cost‐Effectiveness Analysis for Pediatric Immunization in Developing Countries

Context: Developing countries face critical choices for introducing needed, effective, but expensive new vaccines, especially given the accelerated need to decrease the mortality of children under age five and the increased immunization resources available from international donors. Cost‐effectiveness analysis (CEA) is a tool that decision makers can use for efficiently allocating expanding resources. Its use in developing countries, however, lags behind that in industrialized countries. Methods: We explored how CEA could be made more relevant to immunization policymaking in developing countries by identifying the limitations for using CEA in developing countries and the impact of donor funding on the CEA estimation. We conducted a comprehensive literature search using formal search protocols and hand searching indexed and gray literature sources. We then systematically summarized the application of CEA in industrialized and developing countries through thematic analysis, focusing on pediatric immunization and methodological and contextual issues relevant to developing countries. Findings: Industrialized and developing countries use CEA differently. The use of the Disability‐Adjusted Life Year (DALY) outcome measure and an alternative generalized cost‐effectiveness analysis approach is restricted to developing countries. In pediatric CEAs, the paucity of evaluations and the lack of attention to overcoming the methodological limitations pertinent to children's cognitive and development distinctiveness, such as discounting and preference characterization, means that pediatric interventions may be systematically understudied and undervalued. The ability to generate high‐quality CEA evidence in child health is further threatened by an inadequate consideration of the impact of donor funding (such as GAVI immunization funding) on measurement uncertainty and the determination of opportunity cost. Conclusions: Greater attention to pediatric interventions and donor funding in the conduct of CEA could lead to better policies and thus more worthwhile and good‐value programs to benefit children's health in developing countries.     

Vitamin E Deficiency in the Monkey. IV. Further Studies of the Anemia with Emphasis on Bone Marrow Morphology

Nuclear abnormalities were observed in all the erythroid precursors in thebone marrow of vitamin E-deficient monkeys. Many of these cells were multinucleated. The remainder of the marrow elements appeared normal. Reasonsfor considering the anemia to be primarily due to inadequate erythropoiesisare given.

Serum iron, glutathione stability of the erythrocytes, hemoglobin electrophoresis, osmotic fragilities and platelet counts were all found to be normalin the vitamin E-deficient monkey.

Submitted on March 23, 1962 Accepted on May 12, 1962