Cryptococcal Meningitis in Patients with the Acquired Immunodeficiency Syndrome

The optimum therapy for cryptococcal meningitis in patients with the acquired immunodeficiency syndrome (AIDS) remains unresolved. Traditional therapy consists of amphotericin B with or without flucytosine. Obstacles exist in administering these agents to patients with AIDS. Mortality rates during initial therapy are relatively high. Given the lack of proved benefit, we do not recommend adding flucytosine to amphotericin B routinely. The search for more efficacious and less toxic agents continues. The oral triazoles, especially fluconazole, have increased the options for treatment of this disease. New strategies and novel approaches in managing cryptococcal meningitis in patients with AIDS continue to be developed.     

FEASIBILITY OF CONDUCTING CARDIOVASCULAR OUTCOME RESEARCH IN AUSTRALIAN GENERAL PRACTICE: RESULTS FROM THE ANBP2 PILOT STUDY

1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.     

Use of metoclopramide, domperidone, and cisapride in the management of diabetic gastroparesis

The pathophysiology, diagnosis, and treatment of diabetic gastroparesis are reviewed, and the mechanisms of action, pharmacokinetics, clinical efficacy, adverse effects, and dosage of metoclopramide, domperidone, and cisapride are described. Diabetic gastroparesis is a state of delayed gastric emptying that reportedly affects 20-30% of diabetic patients. Symptoms include nausea, early satiety, postprandial bloating and fullness, and vomiting. Diabetic gastroparesis has been managed most successfully with drugs that stimulate gastric emptying. Of the three agents studied--metoclopramide, domperidone, and cisapride--only metoclopramide is commercially available in the United States. The clinical efficacy of metoclopramide, domperidone, and cisapride has been well documented in several placebo-controlled trials. Metoclopramide effectively decreases mean gastric emptying time, although tolerance to this stimulation of gastric emptying may develop with long-term therapy. However, symptomatic relief persists with long-term therapy because of metoclopramide's antiemetic properties. Domperidone, which has also been shown to stimulate gastric motility and to possess antiemetic properties, improves symptoms in patients suffering from diabetic gastroparesis. Cisapride appears to have continued beneficial effects on gastric motility with long-term therapy. All three agents have favorable adverse-effect profiles. Although metoclopramide is currently the first-line agent for the management of gastroparesis, domperidone and cisapride both possess properties that may make them useful alternatives in patients who are unresponsive to or cannot tolerate metoclopramide therapy.     

Inter- and intra-individual variability of non-invasive tear break-up time in Hong Kong Chinese

Non-invasive tear break-up time (NITBUT) has been proposed as a measure of tear film integrity which is superior to the more commonly used tear break-up time (TBUT), since it does not alter the volume or the physicochemical properties of the tear layer by the addition of fluorescein. We measured NITBUT by measuring the time taken for distortions or discontinuities to appear in the reflected image of a grid pattern which covered about 80 per cent of the corneal surface. NITBUT measures were made 100 times on seven Hong Kong Chinese subjects with up to 20 consecutive measures being made on a single day. We also measured NITBUT on one occasion on an unselected population of 52 Hong Kong Chinese subjects. NITBUT shows a skewed distribution in all subjects, with many shorter values and some extremely long values. There are statistically significant variations in NITBUT from day to day, and from subject to subject. The group of 52 subjects also had a skewed NITBUT distribution with many short values and some very long values. The arithmetic mean does not adequately represent NITBUT data, either for individual subjects or for this group of subjects. As many as five to eight measures may be necessary to gain a stable estimate of the NITBUT and stability of the measure is improved if extreme values are omitted. We recommend the use of nonparametric statistics to compare NITBUT values from day to day in or between subjects.     

1/T1 rho and low-field 1/T1 of tissue water protons arise from magnetization transfer to macromolecular solid-state broadened lines.

We argue that, for solutions of immobilized protein and for tissue, the dependence of 1/T1 of solvent protons on B(0) at low fields and 1/T1 rho on B1 for all B(0) are both manifestations of the same underlying phenomena: magnetization transfer between mobile water protons and solid-state broadened protein proton levels. Broadening causes rapid mixing of spin orientation within the transverse plane, at all B(0), unless B1 is greater than the protein internal field; this affects 1/T1 rho of solvent protons by magnetization transfer. Similarly, decreasing B(0) below the internal field mixes all orientations of magnetization, which affects the solvent proton low-field 1/T1 and high-field 1/T2.     

DNA probe technology: implications for service planning in Britain

For certain genetic conditions DNA testing identifies carriers and determines the risk status of foetuses, thus helping parents to make more informed prenatal decisions. Data, collected from three genetic centres in England and Wales from August 1986 to July 1990, are used to describe trends in demand for DNA testing, the impact of DNA tests on carrier risk assessment, and the use of DNA tests in relation to pregnancy outcome. Altogether the data include 23,388 subjects and 681 pregnancies in 8738 families divided into five cohorts by year of entry and referral. The most frequent gene disorders referred to the genetic centres are currently being tested or will soon be tested. For these disorders the initial high level of activity has declined and may have reached steady state. Demand for DNA services is high for cystic fibrosis and Duchenne muscular dystrophy, intermediate for Huntington's disease, and low for adult polycystic kidney disease, phenylketonuria and tuberous sclerosis. Based on these findings we suggest that demand for DNA tests will be high in serious, untreatable and slow progressing conditions with early onset; intermediate for conditions affecting intellect and neurological integrity with later onset; and low for treatable, late-onset conditions, or those for which there is evidence of heterogeneity, and variable penetrance. It would be helpful to assess the extent to which this view of demand is confirmed when the new disorders being DNA tested are considered and for the pattern of activity of DNA testing for some types of cancer. Since no DNA centre could offer a fully comprehensive testing service, it is recommended that a structure is created to audit overall activity, assist in policy formulation, and influence supraregional service organisation, in order that the spread of DNA services be planned as effectively as possible. This structure would facilitate monitoring of the evolution of contract specifications agreed by commissioners and providers on a regional basis.     

Human metabolism of arsenobetaine ingested with fish

1. Six volunteers ingested 74As-labelled arsenobetaine with a fish meal. The retention and distribution of the tracer were studied by body radioactivity measurements. 2. The tracer became rapidly dispersed in soft tissues, with no major concentration in any localized organ or region. 3. In all subjects less than 1% of the ingested activity remained in the body after 24 days. 4. Any losses from the skin were minor in relation to those by other routes of excretion.