Biomedical subjects

A Lau

Publications and source records attributed to A Lau.

94 records · Page 6Linked to original sources

PubMedDate not supplied

Control of RNA content of developing human placenta.

Human placentae obtained early in pregnancy or at full term were examined for RNA content per cell, RNA polymerase types and activities, and chromatin template availability. The RNA:DNA ratio fell from 0.7 at 15 to 20 weeks to 0.4 at 40 weeks of pregnancy. Since RNase activities were similar at both times, the reduction in RNA content was attributed not to increased degradation, but to reduced synthesis. At both stages of pregnancy, about 55 to 60 per cent of the RNA polymerase activity in isolated placental nuclei was accounted for by RNA polymerase II, as judged by suppression of activity with alpha-amanitin and by separation of the extracted polymerases on DEAE-Sephadex. The relative roles of changes in polymerase activity and template availability were measured in nuclei from 20- and 40-week placentae. Nuclei showed 20 per cent greater polymerase activity in full-term than in early placentae, but the template availability of isolated chromatin for transcription by RNA polymerase II was 70 per cent less at full term. We conclude that the reduced amount of RNA per cell in the full-term placenta is due to reduced template availability that more than offsets the slight increase in polymerase activity.

Cell Nucleus↗

PubMedDate not supplied

Pseudobacteremia due to Pseudomonas fluorescens.

Pseudomonas fluorescens was recovered from 62 of 22,270 (0.26%) blood cultures, from 57 patients, over a 22-month period at a pediatric hospital. No illness was attributable to the blood culture isolate. A case-control study identified a significant correlation between the recovery of P. fluorescens in blood culture and concomitant coagulation studies (p less than 0.0001). In all cases blood for coagulation studies had been obtained at the same time as the blood culture. A review of venipuncture technique revealed that occasionally the coagulation study tubes (containing 3.8% sodium citrate) were being inoculated before blood culture bottles. P. fluorescens was subsequently isolated from coagulation tubes and from sodium citrate solutions prepared and dispensed in the hospital for use in coagulation studies. In vitro studies confirmed that sodium citrate solutions supported the growth of P. fluorescens, with preferential growth at 25 degrees C and 4 degrees C. This is the first description of P. fluorescens as a cause of pseudobacteremia. Pseudobacteremia was attributed to cross-contamination of blood cultures following inoculation of contaminated citrated collection tubes.

Adolescent↗

PubMedDate not supplied

Patterns of outcome measurement in Parkinson's disease clinical trials.

The study examines the pattern of use and clinimetric properties of clinical endpoints used in randomized trials for Parkinson's disease (PD). Randomized drug trials for PD were identified through a Medline search conducted from January 1966 until August 1998. The endpoints used in these trials were abstracted. Reports examining the clinimetric properties of the disease-specific scales used in these trials were also abstracted. Data regarding the consistency, accuracy, discrimination and feasibility of scales used in at least 10% of trials were determined. One hundred and thirty-seven articles met the inclusion criteria; 70.8% of trials used some clinical scale for PD as an endpoint. The Unified Parkinson's Disease Rating Scale (UPDRS) was the most commonly used scale (32.8%). Factors independently associated with the use of the UPDRS included: the study location in the US, mean age of subjects over 62.7 years and publication after 1994. The UPDRS was more thoroughly studied and superior in most clinimetric domains compared to scales developed earlier. Few studies included generic health status (2.9%) or cognitive measures (16.8%) as secondary endpoints. There have been definite improvements in the area of disease-specific measurement in PD trials since the introduction of the UPDRS. The results of studies that used instruments with poor or unreported clinimetric properties should be critically interpreted.

Aged↗

PubMedDate not supplied

Effectiveness of clinical pharmacist interventions in a hemodialysis unit.

Many patients with end-stage renal disease are treated with a complex pharmacotherapeutic regimen that requires constant and thorough monitoring. The role of a clinical pharmacist in contributing to the care of patients receiving long-term hemodialysis in an outpatient dialysis unit was assessed. Therapeutic interventions provided routinely by the clinical pharmacist were recorded and then categorized and evaluated by two independent clinical pharmacists with expertise in nephrology pharmacotherapeutics. Of the 205 interventions recorded, 97.6% were initiated by the clinical pharmacist and 91.7% were accepted by the medical team; 80.9% were judged to have primarily affected the quality of care. The purposes of interventions were drug selection in 32.2% of cases, drug discontinuation in 19.0%, dose selection in 24.4%, and therapeutic monitoring in 24.4%. Most interventions were initiated in response to abnormal laboratory test results. When the interventions were ranked according to clinical significance, 34.6% were involved with the preservation of major organ function and 62.4% with improvement of the quality of care to acceptable standards. Of all the interventions accepted by the medical team, 90.5% resulted in positive patient outcome; 7.9% resulted in no observable change or had no effect on outcome. The results demonstrate the potential influence and effectiveness of clinical pharmacy interventions on the drug therapy of patients receiving long-term hemodialysis.

Costs and Cost Analysis↗