Ethics consultation

Hospices in the U.S. were surveyed in 1990 to find out whether service to blacks and Hispanics was affected by admission criteria and hospice service characteristics of hospices located in or near these populations. Hospice characteristics such as reimbursement patterns, staff interventions, and admission criteria were different depending upon the percent of blacks and/or Hispanics in the hospice service area or actually served by the hospice. Care for Hispanics was more dependent on Medicaid and free care than blacks whose care was financed primarily by Medicare and Medicaid. Hospices identified problems in serving Hispanics as language, reimbursement, and severity-of-illness issues. Hospice admission criteria, especially the primary caregiver requirement, were identified as impeding access for blacks. Hispanics were perceived as presenting the most access and service problems and as the most underserved.     

Genomic variation in Trypanosoma cruzi clonal cultures

Spontaneous changes in restriction DNA profiles and pulsed-field gel electrophoresis (PFGE) patterns, along with a concomitant loss of infectivity, were observed in infective clones of Trypanosoma cruzi strain Y either following a number of passages during the exponential growth phase of after subcloning in liver infusion tryptone (LIT) medium using as the probe a genomic fragment of the parasite (pMYP16), indicating naturally occurring rearrangements of DNA sequences. No variation could be detected when the genomic DNA was probed with conserved T. cruzi tubulin and actin genes. There was no correlation between such rearrangements and the life-cycle forms of the parasites, since trypomastigote forms showed the same karyotype and hybridization patterns as did epimastigote forms. The variations observed could be reverted and infectivity, recovered after inoculation of the parasites in newborn mice.     

Differential effects of etomidate, propofol, and midazolam on calcium and potassium channel currents in canine myocardial cells

BACKGROUND: Intravenous anesthetics etomidate, propofol, and midazolam produce negative inotropic effects of various degrees. The mechanism underlying these differences is largely unknown. METHODS: The effects of intravenous anesthetics on L-type Ca2+, transient outward and inward-rectifier K+ channel currents (ICa, IKto, and IK1) were compared in canine ventricular cells using the whole-cell voltage-clamp technique. ICa and IK were elicited by progressively depolarizing cells from -40 to +40 mV, and from -90 to +60 mV, respectively. The peak amplitude and time-dependent inactivation rate of ICa and IK were measured before, during, and after the administration of equimolar concentrations (5, 30, or 60 microM) of etomidate, propofol, or midazolam. RESULTS: Exposure to etomidate, propofol, and midazolam produced a concentration-dependent inhibition of ICa. Midazolam was the most potent intravenous anesthetic; at 60 microM, etomidate, propofol, and midazolam decreased peak ICa by 16 +/- 4% (mean +/- SEM), 33 +/- 5%, and 47 +/- 5%, respectively. Etomidate, propofol, and midazolam given in a 60-microM concentration decreased IKto by 8 +/- 3%, 9 +/- 2%, and 23 +/- 3%, respectively. IK1 was decreased by 60 microM etomidate and midazolam by 20 +/- 6% and 14% +/- 5%, respectively. Propofol had no effect on IK1. CONCLUSIONS: At equimolar concentrations, intravenous anesthetics decreased the peak ICa, IKto, and IK1 with various degrees of potency. Effects of anesthetics on ICa were significantly greater compared with their effects on K+ currents. These findings suggest that the negative inotropic actions of etomidate, propofol, and midazolam are related, at least in part, to decreased ICa. Some effects, such as IK inhibition, may partially antagonize effects of decreased ICa. Indeed, the final effect of these intravenous anesthetics on myocardium will be the sum of these and other sarcolemmal and intracellular effects.     

The incidence of male hermaphroditism in girls with inguinal hernia

The incidence of male hermaphroditism in girls with inguinal hernias is estimated to be 1.4 per cent. From 1961 to 1972, 340 girls were admitted to the Department of Surgery at St. Josephs Hospital for hernial repair. One hundred and two patients had menstruated prior to the follow-up study. Buccal smears from the remaining patients were examined for Y chromatin-positive cells. We observed a zero per cent rate of male hermaphroditism, which is not significantly different from the aforementioned frequency, p greater than 0.05. Large scale prospective studies must be available before any conclusion can be drawn as to whether or not determination of the genetic gender prior to hernial repair in girls should be conducted as a routine procedure.