CAPRISA 018: a phase I/II clinical trial study protocol to assess the safety, acceptability, tolerability and pharmacokinetics of a sustained-release tenofovir alafenamide subdermal implant for HIV prevention in women

INTRODUCTION

Young African women bear a disproportionately high risk for HIV acquisition. HIV technologies that empower women to protect themselves are needed. Safe, potent antiretroviral agents such as tenofovir alafenamide (TAF), formulated as long-acting subdermal implants, offer an innovative solution.

METHODS AND ANALYSIS

CAPRISA 018 is a phase I/II trial to evaluate the safety, acceptability, tolerability and pharmacokinetics (PKs) of a TAF free base subdermal silicone implant containing 110 mg of TAF with an anticipated 0.25 mg/day release rate.The phase I trial (n=60) will assess the safety of one implant inserted in six participants (Group 1), followed by dose escalation components (Groups 2 and 3) assessing the safety, tolerability and PK of one to four TAF 110 mg implants releasing between 0.25 mg and 1 mg daily in 54 healthy women at low risk for HIV infection. Data from this phase I trial will be used to determine the dosing, implant location and implant replacement interval for the phase II trial.The phase II component (Group 4) will assess extended safety, PK, tolerability and acceptability of the implant in 490 at risk women, randomised in a 1:1 ratio to the TAF implant and placebo tablet or to the placebo implant and an oral pre-exposure prophylaxis tablet. Safety will be assessed by calculating the percentage change in creatinine clearance from baseline at weeks 4, 12, 24, 36, 72, 96 and 120, compared with the percentage change in the control group.

ETHICS AND DISSEMINATION

The South African Health Products Regulatory Authority and the University of KwaZulu-Natal's Biomedical Research Ethics Committee have approved the trial. Results will be disseminated through open access peer reviewed publications, conference presentations, public stakeholder engagement and upload of data into the clinical trials registry.

TRIAL REGISTRATION NUMBER

PACTR201809520959443.

Pilot evaluation of a second-generation electronic pill box for adherence to Bedaquiline and antiretroviral therapy in drug-resistant TB/HIV co-infected patients in KwaZulu-Natal, South Africa

BACKGROUND

The introduction of Bedaquiline, the first new antimycobacterial drug in over 40 years, has highlighted the critical importance of medication adherence in drug-resistant tuberculosis (DR-TB) treatment to prevent amplified drug-resistance and derive sustained benefit. Real-time electronic dose monitoring (EDM) accurately measures adherence and allows for titration of adherence support for anti-retroviral therapy (ART). The goal of this study was to evaluate the accuracy and acceptability of a next-generation electronic pillbox (Wisepill RT2000) for Bedaquiline-containing TB regimens.

METHODS

Eligible patients were DR-TB/HIV co-infected adults hospitalized for the initiation of Bedaquiline-containing treatment regimens in KwaZulu-Natal, South Africa. A one-way crossover design was used to evaluate levels of adherence and patient acceptance of EDM. Each patient was given a Wisepill device which was filled with ART, Levofloxacin or Bedaquiline over three consecutive weeks. Medication adherence was measured using Wisepill counts, patient-reported seven-day recall, and weekly pill count. An open-ended qualitative questionnaire at the end of the study evaluated participant acceptability of the Wisepill device.

RESULTS

We enrolled 21 DR-TB/HIV co-infected inpatients admitted for the initiation of Bedaquiline from August through September 2016. In aggregate patients were similarly adherent to Bedaquiline (100%) compared to Levofloxacin (100%) and ART (98.9%) by pill count. Wisepill was more sensitive (100%) compared to seven-day recall (0%) in detecting non-adherence events (p = 0.02). Patients reported positive experiences with Wisepill and expressed willingness to use the device during a full course of DR-TB treatment. There were no concerns about stigma, confidentiality, or remote monitoring.

CONCLUSION

In this pilot study patients were highly adherent to Bedaquiline by all adherence measures. However, there was lower adherence to ART by pill count and Wisepill suggesting a possible challenge for adherence with ART. The use of EDM identified significantly more missed doses than seven-day recall. Wisepill was highly acceptable to DR-TB/HIV patients in South Africa, and is a promising modality to support and monitor medication adherence in complex treatment regimens.

Implementing isoniazid preventive therapy in a tuberculosis treatment-experienced cohort on ART

SETTING

Urban clinical research site in Durban, South Africa.

OBJECTIVE

To describe outcomes associated with the implementation of isoniazid preventive therapy (IPT) in a cohort of tuberculosis (TB) treatment-experienced human immunodeficiency virus (HIV) infected patients on antiretroviral therapy (ART).

DESIGN

We conducted a secondary analysis of data collected between October 2009 and October 2013 from patients enrolled in a prospective cohort study conducted in Durban, South Africa.

RESULTS

Of the 402 patients enrolled in the parent study, 344 (85.6%) were eligible for IPT, 212 of whom (61.6%) initiated IPT. Of those who initiated IPT, 184 (86.8%) completed the 6-month course, while 24 (11.3%) permanently discontinued IPT, 3.8% of whom due to side effects. More women than men initiated IPT (n = 130, 61.3% vs. n = 82, 38.7%, P = 0.001). Overall median adherence to IPT was 97.6% (interquartile range 94.2-99.4). There were 22 cases of incident TB in this cohort: 13 occurred before IPT and 9 after (incidence rate ratio 0.67, 95%CI 0.29-1.58, P = 0.362).

CONCLUSIONS

IPT implementation among ART and TB treatment-experienced patients was well tolerated, with good completion rates and fewer TB cases diagnosed after IPT.

Awareness and knowledge of prophylaxis for infective endocarditis in patients with severe rheumatic heart disease

Prevention of infective endocardit s (IE) is mportant because it has a high mortalty rate.This study sets out to to gather information from patients who were at risk of developing IE of their knowledge of the need for prophylaxis for the disease. Forty-one black patients suffering from severe rheumatic heart disease (RHD) were interviewed. Only one patient (2.4%) was regularly visiting a dentist to maintain good oral health and only five (12.2%) had received advice about the need for antibiotic cover prior to dental extraction. The vast majority of patients (97.5%) visited a dentist only when driven by dental pain, 36.6 % had to travel for more than an hour to reach their nearest dentist, and 87.8% indicated that they brushed their teeth. It may be concluded that in this group of black patients with severe RHD there was a lack of knowledge of the need for and of measures recommended for prophylaxs against IE. In addition, attempts by the health care team to ensure good oral health and access to dental care for these patients were inadequate, if not non-existent.

Effect of desloratadine on patients with allergic rhinitis and exercise-induced bronchoconstriction: a placebo controlled study

BACKGROUND

Exercise induced broncho-constriction (EIB) is a significant problem in asthmatic patients. The link between allergic rhinitis and asthma is now well established. Patients with allergic rhinitis may have EIB.

OBJECTIVE

This study compared the effects of desloratadine and placebo on EIB in a group of patients with allergic rhinitis and EIB.

METHODS

This was a double blind placebo controlled, randomized, crossover study. Exercise challenge tests were performed before and after 7 days of treatment with either 5 mg desloratadine or placebo. Patients then underwent a washout period for 7 days and were crossed over to receive either 5mg desloratadine or placebo. The exercise challenge tests were repeated.

RESULTS

Desloratadine had no effect on the reduction in percentage fall in FEV(1), the AUC (0-60 min) and the time to recovery.

CONCLUSIONS

Desloratadine has no effect in attenuating the broncho-constriction caused by exercise in patients with allergic rhinitis and exercise induced broncho-constriction.

CLINICAL IMPLICATIONS

Patients with allergic rhinitis and exercise induced broncho-constriction must be treated with either a beta(2)-agonist or LRTA for relief or prophylaxis of their EIB.

CAPSULE SUMMARY

Desloratadine does not have an effect on exercise induced bronchoconstriction. Patients with allergic rhinitis with exercise induced bronchoconstriction who are on desloratadine will still require treatment with beta(2) agonist or leukotriene receptor antagonist for their symptoms.

Effects of antihypertensive drugs on the unborn child: what is known, and how should this influence prescribing?

This review discusses the use of antihypertensive drugs in acute and long term treatment of hypertensive disorders of pregnancy, including their placental transfer and adverse effects on the fetus. All antihypertensive agents cross the placental barrier and are present in varying concentrations in the fetal circulation, with varying resultant effects on fetal metabolism. Antihypertensive drugs that are lipid soluble will pass through the placental barrier with ease whereas the most polar will not. Placental transfer diminishes under conditions that decrease the surface area or increase the thickness of the placenta. Highly protein-bound drugs form complexes which impair placental transfer while unbound drugs cross the placenta easily. The ionised drug form is highly charged and cannot cross lipid membranes while the un-ionised form can easily cross the placenta. A decrease in placental blood flow can slow down the transfer of lipid soluble drugs to the fetus. Close monitoring of the fetal and maternal condition is necessary for the rest of the pregnancy after antihypertensive therapy is commenced. Methyldopa is the initial drug of choice for long term oral antihypertensive therapy in pregnancy. Neither short term nor long term use of methyldopa is associated with adverse effects. In the short term (<6 weeks) beta-receptor antagonists are effective and well tolerated provided there are no signs of intrauterine growth impairment. ACE (angiotensin converting enzyme) inhibitors are contraindicated in the second and third trimesters of pregnancy because they are teratogenic. Intravenous dihydralazine is widely used for rapid reductions of severely elevated blood pressure. The use of nifedipine concurrently with MgSO4 must be approached with caution because the combination is associated with severe hypotension, neuromuscular blockade and cardiac depression. In the last decade, knowledge of antihypertensive drugs used in pregnancy has improved and new drugs, e.g. calcium antagonists, which have been shown to have great potential for use in pregnancy, have been introduced. Safety for the fetus with newer drugs has not yet been adequately evaluated. Currently, well established and cost effective drugs such as methyldopa (long term use) and intravenous dihydralazine (rapid reduction) are the agents of choice to treat hypertensive disorders of pregnancy.

How do South African obstetricians manage hypertensive disorders of pregnancy--a survey

OBJECTIVE

To determine the current management of hypertensive disorders of pregnancy in South Africa.

METHOD

A postal questionnaire was sent to 600 South African obstetricians.

RESULTS

The response rate was 72% (432/600), with 425 questionnaires suitable for analysis. South African obstetricians disagree on the definitions of various hypertensive disorders of pregnancy. Methyldopa was the antihypertensive used most frequently for the treatment of mild to moderate hypertension (diastolic blood pressure between 90 and 109 mmHg), while intravenous dihydralazine was preferred in severe hypertension (diastolic blood pressure > or = 110 mmHg and proteinuria > or = +2). To stop convulsions in eclampsia, 256 respondents (60%) said they would use diazepam, 28 (11%) said they would continue with a diazepam infusion, and the remaining 228 (89%) preferred magnesium sulphate (MgSO4) to prevent further convulsions. The intramuscular route was the preferred method of administration for MgSO4. In cases of eclampsia, 273 respondents (64%) said they would use intravenous dihydralazine to lower high blood pressure (> or = 160/110 mmHg) and proteinuria; 98 respondents (23%) said they would use methyldopa, 38 (9%) nifedipine, and 8 (2%) apresoline. Eight (2%) said they would not use antihypertensives. In patients with severe pre-eclampsia and impending eclampsia, 330 respondents (78%) said they would use MgSO4 as prophylaxis, 46 (11%) diazepam, and 6 (1.4%) phenobarbitone. Forty-three of the respondents did not prescribe prophylactic anticonvulsant therapy. To prevent pre-eclampsia, 247 of the respondents (58%) said they would prescribe low-dose aspirin.

CONCLUSION

This study demonstrates that South African obstetricians show great uniformity in terms of the treatment of hypertensive disorders of pregnancy.

HLA-A, -B, -DR and -DQ antigens in black patients with infective endocarditis

In order to determine if genetically determined immune response factors could play a role in the pathogenesis of infective endocarditis in black patients, we performed HLA-A and HLA-B typing in 38 patients with this disease and HLA-DR and HLA-DQ typing in 33 and 27 of these individuals, respectively. HLA typing was also carried out in a control group of normal black adults. The HLA typing was done by means of a standard microlymphocytotoxicity test. No difference in HLA-A, HLA-B, HLA-DR and HLA-DQ antigen frequencies between patients and controls were noted. This study did not provide any evidence that genetic factors could contribute to a disposition to infective endocarditis.

HLA-antigens in black patients with hepatocellular carcinoma

To determine whether genetically determined immune response factors could be involved in the pathogenesis of hepatocellular carcinoma, we performed HLA-A and HLA-B typing in 55 black patients with histologically-proven hepatocellular carcinoma, and HLA-DR and HLA-DQ typing in 47 of these patients. The HLA typing was also carried out in a control group of normal black patients. The HLA typing was done by a standard microlymphocytotoxicity method. No difference in HLA-A, HLA-DR and HLA-DQ frequencies between patients and controls were noted. HLA-B21 was present in 10.9% of patients compared to 1.8% of control subjects (corrected p < 0.005; relative risk = 6.6) and HLA-B49 was present in 7.3% of patients compared with 1.1% of normal control subjects (corrected p < 0.007; relative risk = 7.1). These findings suggest that genetic factors may play a role in the pathogenesis of hepatocellular carcinoma.

Drug management of hypertensive disorders of pregnancy

Drugs used in the acute and long-term management of hypertension in pregnancy and the preeclampsia-eclampsia syndrome have been reviewed and their therapeutic effects and maternal and fetal adverse effects have been considered. The review also focuses on recent developments in the areas of prevention and management of pre-eclampsia-eclampsia syndrome. Although a number of new drugs have emerged, as potentially useful in the management of hypertension in pregnancy and pre-eclampsia-eclampsia syndrome, some remain at the cornerstone of therapy; for example, methyldopa for long-term treatment of chronic hypertension, hydralazine or nifedipine for rapid reduction of severely elevated blood pressure, and magnesium sulphate for eclampsia. Some of these agents, especially the calcium antagonists, show promise in that their use is associated with fewer side effects. Safety for the fetus, however, has not been adequately evaluated yet. Neither aspirin nor calcium supplements appear to improve the outcome in pregnancy. Currently, the dilemma whether to treat hypertension in pregnancy and pre-eclampsia-eclampsia syndrome with old, established, cost-effective drugs or the promising newer drugs provides an interesting academic challenge.

HLA-A, B, DR, and DQ antigens in Indian patients with severe chronic rheumatic heart disease

To determine whether genetic factors could be involved in the pathogenesis of rheumatic heart disease, we performed HLA-A and HLA-B typing in 59 Indian patients with severe chronic rheumatic heart disease requiring cardiac surgery, and HLA-DR and HLA-DQ typing in 58 of these patients. The HLA typing was done by a standard microlymphocytotoxicity method. Patients were 12 to 59 years old (mean 32.9 years). No significant differences in HLA-A, HLA-B, HLA-DR and HLA-DQ frequencies between patients and controls were noted. The role of genetically determined immune-response factors in the pathogenesis of chronic rheumatic heart disease was not evident in this study.

The effect of a low dose versus a conventional dose of hydrochlorothiazide on ventricular fibrillation threshold and electrolyte levels in laboratory rats

We studied the effect of hydrochlorothiazide on metabolic and electrolyte parameters. In the first protocol, six groups of rats were studied to determine whether changes in ventricular fibrillation threshold, and serum and myocardial potassium occur after treatment with different doses of hydrochlorothiazide; three groups (N = 15) served as controls and the other three groups (N = 15) were given different doses of hydrochlorothiazide for a 3 month period. Two rats from each group were sacrificed daily. One rat heart was perfused using the Langendorff perfusion apparatus and the other used for myocardial potassium analysis. Blood was also collected for serum potassium analysis. There was no change in the threshold for ventricular fibrillation in groups treated with 0.04 mg and 0.09 mg hydrochlorothiazide compared to control values. There was a nonsignificant decrease in serum and myocardial potassium levels in rats treated with 0.04 mg and 0.09 mg hydrochlorothiazide compared to control. Seven of the 15 rats treated with 0.18 mg hydrochlorothiazide showed significantly lower ventricular fibrillation threshold levels and decreased serum potassium (P < 0.02) compared to control animals. In addition, a significant decrease in myocardial potassium was noted (P < 0.05). In the second protocol, 8 of the 15 rats treated with 0.18 mg hydrochlorothiazide showed reduced ventricular fibrillation threshold and serum potassium levels (P < 0.05). A significant decrease in myocardial potassium was also observed (P < 0.05). These variables were corrected by the intragastric administration of potassium salts. The present study indicates that 0.04 mg and 0.09 mg hydrochlorothiazide have no effect on ventricular fibrillation threshold level or on serum or myocardial potassium levels. There was a significant decrease in ventricular fibrillation threshold and serum and myocardial potassium levels in 7 of the 15 animals studied in protocol one and 8 of the 15 animals studied in protocol two, treated with 0.18 mg hydrochlorothiazide and these variables were corrected by the intragastric administration of potassium salts.

Hexane cardiotoxicity--an experimental study

Ventricular arrhythmia has been postulated as a possible cause of death in young black children who abuse volatile substances, primarily benzine and certain glues that contain n-hexane. A series of protocols were designed to determine the effect of n-hexane on myocardial function and morphology in male laboratory rats. In the first protocol, experiments were designed to study the effect of n-hexane in initiating ventricular fibrillation and in modifying myocardial magnesium and potassium levels. The results showed that the thresholds for ventricular fibrillation and myocardial magnesium and potassium levels were reduced compared to control values. In the second protocol, n-hexane-treated rats were supplemented with intragastric administration of magnesium and potassium salts. The outcome of the experiments indicated that although the myocardial magnesium and potassium levels were corrected, the threshold for ventricular fibrillation remained low compared to control values. In the third protocol, experiments were designed to examine myocardial morphology by electron microscopy. Cellular changes were observed in the myocardium as a result of administering n-hexane. These cellular changes were considered to be responsible for the decreased threshold for ventricular fibrillation. The present study indicates that n-hexane, a constituent of benzine and certain glues, is cardiotoxic.

Zinc, hydrochlorothiazide and sexual dysfunction

This study was designed to test the hypothesis that hydrochlorothiazide a diuretic used to treat hypertension depletes body zinc and thereby cause sexual dysfunction. Serum zinc and sexual dysfunction were measured in 39 middle aged hypertensive men who had been taking hydrochlorothiazide in average daily doses of between 25 and 50 mg daily for at least six months, and a control group of 27 unmedicated middle aged normotensive men. The medicated group had a higher incidence of sexual dysfunction (56 pc) as compared to 11 pc in the control group. The use of hydrochlorothiazide did affect serum zinc levels significantly in 20 patients. Sexual dysfunction occurred more often in older and overweight patients (p < 0.004). Three of the normotensive men experienced sexual dysfunction probably related to old age. Twenty two of the 39 on hydrochlorothiazide and experiencing sexual dysfunction were divided into two groups of 11 patients. Bloods were taken from the 27 normotensive and 22 hypertensive men receiving hydrochlorothiazide for the analyses of zinc. Subsequently one group of the patients were supplemented with zinc 500 mg daily for 30 days while the other group was supplemented with magnesium chloride 1 g daily for 30 days. The normotensive men were not treated. After 30 days, bloods were again taken from the three groups of analyses for zinc and magnesium. Serum zinc was significantly decreased (p < 0.05) by hydrochlorothiazide and a non significant decrease in serum magnesium (p = ns) was observed. After supplementation with zinc, the serum zinc levels returned to normal only in eight patients. There was improvement in the symptoms of sexual dysfunction in five patients. Two patients gained weight. Hydrochlorothiazide decreased serum zinc levels (p < 0.05) and was unchanged with magnesium supplementation but the serum magnesium returned to normal values. Improvement of symptoms of sexual dysfunction was positive in one patient. This study shows that low serum zinc levels may be associated with sexual dysfunction but the definitive role of zinc in the pathogenesis of sexual dysfunction will remain controversial.

Intravenous isradipine in the management of severe hypertension in pregnant and nonpregnant patients. A pilot study

To determine the appropriate dosage regimen of isradipine in black patients with severe hypertension of pregnancy, 10 patients (gestational age, 30 to 38 weeks; diastolic blood pressure [DBP], 110 to 148 mm Hg; no hypertensive crises; and normal central venous pressure) were given an isradipine infusion while the fetal heart rate was continuously recorded using a cardiotocograph. The infusion rate of isradipine was adjusted at regular intervals until control (DBP < 95 mm Hg) was achieved. The optimal dosage regimen in black patients was found to be an initial dose of 0.15 micrograms/kg/min, with increments of 0.0025 micrograms/kg/min every 15 min until control is achieved. Thereafter, a maintenance infusion of 0.15 micrograms/kg/min can be commenced. This dosage regimen is associated with neither maternal hypotension nor fetal heart rate deceleration. A second group of 10 patients (9 men and 1 woman) with DBP > 115 mm Hg (range, 117 to 135 mm Hg) and no features of hypertensive crises were also studied. The optimal dosage regimen in this patient group differed from the other in two respects: dosage increments could be made more rapidly (at 10-min intervals); and the dosage that produced blood pressure control needed to be continued for 30 min before the maintenance infusion was commenced. This regimen was not associated with hypotension.

Intravenous isradipine in the management of severe hypertension of pregnancy in black patients: a pilot study

The ideal antihypertensive agent for lowering very high blood pressure levels rapidly in severe hypertension of pregnancy still eludes researchers. This pilot study was conducted to determine the appropriate dosage regimen for isradipine in black patients with severe hypertensive disorders of pregnancy. Ten black patients with gestational age > or = 30 (range 30-38) weeks and diastolic blood pressure (DBP) > or = 110 (range 110-148) mmHg following 2 h of bed rest were recruited following informed consent. None of the patients had symptoms or signs of hypertensive crisis. After correction of hypovolaemia (using central venous pressure monitoring) with Ringer's lactate, high blood pressure was lowered by an isradipine infusion. Fetal heart rate was continuously recorded using a cardiotocograph. All blood pressure measurements were made using the same mercury sphygmomanometer by a single observer. The infusion rate of isradipine was adjusted at regular intervals until blood pressure control (DBP < 95 mmHg) was achieved. The optimal dosage regimen in black patients was found to be an initial dose of 0.15 microgram kg-1 min-1 with increments of 0.0025 micrograms kg-1 min-1 every 15 min until blood pressure control is achieved. Thereafter, a maintenance infusion of 0.15 microgram kg-1 min-1 can be initiated. This dosage regimen is associated with neither maternal hypotension nor fetal heart rate deceleration.

Randomised double-blind comparative study of efficacy and safety of hydroflumethiazide and reserpine and chlortalidone and atenolol in the treatment of mild to moderate hypertension in black patients

This randomised, double-blind study compared the efficacy and safety of a fixed combination of hydroflumethiazide 50 mg and reserpine 0.125 mg (H-R) and chlortalidone 12.5 mg and atenolol 50 mg (C-A) in adult black patients with mild to moderate hypertension (a resting supine diastolic blood pressure (DBP) between 95 and 115 mmHg after a two week placebo washout period). If the DBP did not reach 90 mmHg after four weeks, the dosage was doubled. There were 27 patients in the H-R group and 22 in the C-A group who completed the study. In the H-R group, supine systolic and diastolic BP were reduced from 156.5 (95% confidence intervals 150.1-162.9) and 102.0 (97.5-106.5) mmHg to 137.0 (130.6-143.4) and 87.4 (83.0-91.9) mmHg, respectively. The corresponding values in the C-A group were 154.1 (147.0-161.2) and 103.4 (98.5-108.4) mmHg to 136.4 (129.3-143.5) and 91.2 (86.2-96.1) mmHg, respectively. Normalisation, response and control of DBP was achieved in 88.9, 92.6 and 100% of patients, respectively, in the H-R group, and in 81.8, 95.5 and 95.5% of patients in the C-A group, respectively. The dose was doubled in 14.8% of patients on H-R and 40.1% on C-A. No clinically significant abnormalities in laboratory variables and no serious adverse effects were encountered. Both drugs have been shown to be efficacious and safe in the treatment of mild to moderate hypertension in black patients.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of therapeutic doses of paracetamol on liver function in the rat perfused liver

The isolated liver perfusion technique was used to study the effect of therapeutic doses of paracetamol on hepatic gluconeogenesis and bromosulphthalein clearance from the perfusate and biliary excretion of the dye in the rat. Six groups of rats were studied; those in the three experimental groups were given 0.02 g kg-1 paracetamol daily for ninety days. The livers of animals in the control group and in one of the experimental groups were perfused with a medium containing pyruvate. The animals in the second experimental and control group were perfused with a medium containing bromosulphthalein (10 mg/100 mL). The livers of the third experimental and control group were subjected to histological examination. The rate of glucose formation and glucose concentrations were decreased, while, lactate levels and lactate: pyruvate ratios were increased in paracetamol-treated rats. The mean concentration of bromosulphthalein in the perfusate and biliary excretion of the dye were decreased. Macro and micro vesicular fatty change was present in the livers of paracetamol-treated rats. This study demonstrates that chronic administration of therapeutic doses of paracetamol to rats adversely affects liver function, as evidenced by impaired gluconeogenesis and bromosulphthalein clearance from the perfusate, and excretion of the dye into the bile, and provides histological evidence of hepatic damage in rats.

The effects of hexane on rat myocardium: a morphometric and morphological study

Specimens from the left ventricular myocardium of 10 rats that had been exposed to subcutaneously administered hexane for 30 days were morphometrically and morphologically examined. Other than the presence of occasional necrotic fibres in hexane-treated animals, there was little difference in the histological appearance of myofibres in control or experimental specimens. There was a slight reduction in the average diameter of cardiac myofibres after exposure to hexane. Pathological ultrastructural changes of the myofibres were noted in the experimental and not in the control groups. Mitochondrial oedema and necrosis and myofilament disorganization and dissolution were significant changes noted in the experimental group. These pathological changes suggest that hexane, a constituent of glue and benzine, is cardiotoxic.

A comparative study of isradipine SRO and enalapril in black patients with mild-to-moderate hypertension

Fifty-two black men who had supine diastolic blood pressures (DBP) above 95 mm Hg at the end of a 2-week placebo wash-out period were randomized to receive either isradipine SRO at 2.5 mg/day or enalapril at 10 mg/day for 8 weeks. After 4 weeks, the dosages were doubled if DBP remained above 90 mm Hg. Reductions in blood pressure were comparable in both groups. Mean supine DBP was reduced from 100.6 to 93.9 mm Hg in the isradipine-treated group, and from 103.9 to 98.2 mm Hg in the enalapril-treated group. At the end of the study, 24/27 patients were taking 5 mg isradipine SRO once daily, and 20/25 patients were taking 20 mg enalapril once daily. There were no serious adverse events. The results of this study indicated that monotherapy with isradipine SRO at the recommended initial dosage of 5 mg once daily is appropriate in black patients with hypertension. This was, however, not the case with enalapril at 10 mg once daily. The concurrent administration of a diuretic with enalapril may be more appropriate.

Complications associated with percutaneous needle biopsy of the liver when one, two or three specimens are taken

The diagnostic yield of blind percutaneous liver biopsy is improved when two or three specimens are taken during the procedure by redirecting the needle through a single entry-site, without exposing the patient to a greater risk of complications provided that standard precautions are taken. This study was designed to obtain further data on the safety of this procedure at King Edward VIII Hospital, Durban. During the period 1984-1990 (inclusive) a total of 2,646 biopsies were carried out: a single specimen was obtained in 834 patients, two specimens in 983 patients and three in 829 patients. Complications directly attributable to the procedure occurred in 24 patients who had one specimen, 20 who had two, and 19 who had three specimens taken during the biopsy. A single specimen had been obtained from three of the eight patients who had died, two specimens had been taken from another patient, and three specimens were obtained from the other four patients, i.e. patients in whom two or three specimens were taken did not have a higher incidence of pain, symptomatic hypotension, biliary peritonitis or death than those in whom one specimen was taken. Accordingly, when blind percutaneous needle biopsy of the liver is carried out, two specimens should be obtained by redirecting the needle through a single entry site as this improves the diagnostic yield without increasing complications. The morbidity and mortality associated with liver biopsy in this hospital is, however, high. Good technique, careful monitoring of patients after biopsy and prompt and aggressive resuscitation are essential if the mortality rate is to be reduced.

A comparison of the acute hypotensive effects of two different doses of nifedipine

To determine whether a dose of 5 mg of nifedipine would be useful in the treatment of hypertensive emergencies, we compared the acute hypotensive effects of two different doses of nifedipine, 5 mg and 10 mg, in patients with severe hypertension. In this prospective, randomized, double-blind study, 30 consecutive black patients with diastolic blood pressure that was equal to or greater than 115 mm Hg received either a 5 mg or 10 mg nifedipine capsule and a placebo capsule, which matched that of the alternative strength. Patients were asked to bite the capsules and swallow the contents. Blood pressure response over 4 hours and adverse effects were monitored. Mean systolic blood pressure was reduced from 191.7 mm Hg (95% confidence interval 170.8 to 212.7 mm Hg) to 157.9 mm Hg (137.0 to 178.9 mm Hg) and 206.1 mm Hg (185.1 to 227.0 mm Hg) to 153.7 mm Hg (132.8 to 174.7 mm Hg) in patients who were given 5 mg and 10 mg doses of nifedipine, respectively. Mean diastolic blood pressure in the group of patients that received 5 mg doses of nifedipine decreased from 128.2 mm Hg (115.6 to 140.7 mm Hg) to 105.2 mm Hg (92.7 to 117.7 mm Hg); the corresponding values in the group that received 10 mg doses of nifedipine were 129.9 mm Hg (117.4 to 142.5 mm Hg) and 97.5 mm Hg (85.0 to 110.1 mm Hg), respectively. The minimum mean systolic blood pressures occurred 20 and 25 minutes after administration of the 5 mg and 10 mg capsules, respectively; the minimum diastolic blood pressures were reached after 20 and 30 minutes, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of supra-therapeutic doses of rifampicin on liver function in the perfused rat liver

The isolated liver perfusion model was used to study the effects of supra-therapeutic doses of rifampicin on hepatic gluconeogenesis and bromosulphthalein (BSP) clearance from the perfusate and biliary excretion of the dye in the rat. Three groups of rats randomly assigned to a control and two experimental groups were studied; those in the experimental groups were given 4 mg rifampicin per os daily for 90 days. The control group was untreated. The livers of the control and one experimental group were perfused with a medium containing pyruvate and subsequently these livers were perfused with a medium containing bromosulphthalein. The livers of the second experimental group were subjected to histological examination. The rate and the concentration of glucose was decreased, lactate levels and lactate: pyruvate ratios were increased in the experimental animals. The mean perfusate BSP and biliary excretion of the dye was decreased in the experimental group. Fatty change was present in the livers of rifampicin treated rats. This study demonstrates that the isolated liver model has proved to be both suitable and useful for the study of the effects of drugs and that chronic administration of supra-therapeutic doses of rifampicin to rats adversely affected liver function. It also produces histological evidence of hepatic damage in rats.

The use of drug level measurements in adult patients receiving theophylline, anti-epileptic drugs and amikacin

This prospective study was conducted to determine how frequently measurement of drug levels was used in the management of adult patients receiving theophylline, phenytoin, phenobarbitone, carbamazepine or aminoglycosides in a large hospital. Fifty consecutive outpatients with asthma and 40 with epilepsy were interviewed and their records reviewed to determine which drugs had been prescribed and whether a level of the appropriate drug had been measured in the previous six months. Also, the records of 40 in-patients who were currently receiving amikacin were studied to determine whether serum levels had been measured at any stage during therapy with this drug. Serum theophylline levels were measured in only four (eight pc) patients who were taking this drug and were below the target range in two patients. Serum levels had been measured in 21 (52.5 pc) of 40 patients who were receiving 45 anti-epileptic drugs and were within the target in only nine. Serum amikacin levels were measured in 15 (37.5 pc) patients; blood had been taken for both peak and trough levels in 10 patients and found to exceed the target range in two patients. This study revealed that measurement of serum concentrations of theophylline, anti-epileptic drugs and amikacin was underutilised in the management of adult patients receiving these drugs at this hospital.

Influence of ethyl alcohol when given alone or in combination with potassium and/or magnesium supplements on ventricular fibrillation threshold levels in laboratory rats

Five groups of rats were studied in an investigation to determine whether changes in the ventricular fibrillation threshold (VFT) occur when ethyl alcohol (EtOH) is given alone or in combination with K+ and/or Mg2+ supplements; the first group (n = 20) served as controls, the second (n = 18) was given only EtOH, the third (n = 18) EtOH+KCl, the fourth (n = 16) EtOH+MgCl2, and the fifth (n = 18) EtOH+MgCl2 + KCl for a 9 month period. Two rats from each group were killed on each day. One rat heart was perfused using the Langendorff apparatus and the other used for tissue electrolyte analyses. A significant fall in the mean VFT (9.7 +/- SD 1.9 mA vs 4.5 +/- 1.6 mA; P less than 0.0001) was noted in the rats given EtOH solution as drinking water for 9 months, and a significant increase in the VFT levels was seen in the Mg(2+)-supplemented group (9.7 +/- 1.9 mA vs 18.9 +/- 4.1 mA; P less than 0.0001) and in the K+ + Mg2+ supplemented group (9.7 +/- 1.9 mA vs 15.8 +/- 1.3 mA; P less than 0.0001) compared to controls. In addition, an increase in the heart rate was observed in the group supplemented with Mg2+ (213 +/- 8 beats/min vs 231 +/- 10 beats/min; P less than 0.0001) as well as in the group supplemented with K+ + Mg2+ (213 +/- 8 beats/min vs 222 +/- 10 beats/min; P less than 0.002) compared to controls. There was no significant change in the coronary blood flow (CF) in any group.(ABSTRACT TRUNCATED AT 250 WORDS)

The effect of hexane on the ventricular fibrillation threshold of the isolated perfused rat heart

This investigation was conducted to determine the influence of hexane on the ventricular fibrillation threshold of the isolated perfused rat heart and myocardial electrolyte levels. Ventricular fibrillation threshold was measured using the Langendorff perfusion apparatus. Heart rate was measured by a universal digital counter and the cardiac flow by collecting the outflow of the heating chamber below the heart into a graduated measuring cylinder. Magnesium and zinc were measured by atomic absorption spectrophotometry and potassium by flame photometry. Two groups of rats were studied; those in the experimental group were given 0.2 ml of hexane and the control group 0.2 ml olive oil subcutaneously for 90 days. Their hearts were removed under anaesthesia. Half of the experimental and control hearts were mounted on the Langendorff perfusion apparatus and the heart rate, coronary flow and ventricular fibrillation threshold were measured. The hearts of the other half were used to measure myocardial electrolyte levels. In the experimental group the ventricular fibrillation threshold decreased (4.72 (S.D. +/- 1.87) vs 9.48 (S.D. +/- 2.98); P less than 0.001). There was no change in the coronary flow and heart rate in between the groups. The mean myocardial potassium levels (2586 (S.D. +/- 162) vs 2968 (S.D. +/- 218) micrograms/g; P less than 0.001), magnesium levels (164 (S.D. +/- 28) vs 208 (S.D. +/- 18) micrograms/g; P less than 0.001) and zinc levels (19.6 (S.D. +/- 4) vs 33.8 (S.D. +/- 6.8) micrograms/g; P less than 0.001) were significantly lower in the hexane-treated group compared to controls. Hexane, a constituent of glue and benzine, is cardiotoxic; marked derangement in myocardial electrolytes and a reduced ventricular fibrillation threshold, indicating an increased myocardial vulnerability to arrhythmias, was noted in the experimental animals.

Isradipine in the treatment of mild to moderate essential hypertension

Male patients with supine diastolic blood pressures above 95 mmHg after placebo therapy received twice daily isradipine (Dynacirc; Sandoz) 1.25, 2.5 or 5.0 mg for 12 weeks. Blood pressures were measured every 14 days. Doses of 2.5 or 5 mg isradipine twice daily significantly reduced supine and erect mean systolic, mean diastolic and mean arterial pressures. Isradipine 1.25 mg twice daily reduced supine mean diastolic and mean arterial pressures only. A dose of 5 mg twice daily was accompanied by an increase in adverse reactions. The recommended dose of isradipine is 2.5 mg twice daily.

Circulating CA-195 in hepatocellular carcinoma and metastatic hepatic carcinoma

This study was conducted to determine the role of a relatively new tumor marker, CA-195, in the diagnosis of hepatocellular carcinoma and metastatic hepatic carcinoma, and in distinguishing between these two conditions. CA-195 levels were measured using a commercially available immunoradiometric assay (Tandem-R CA-195) in 30 black inpatients with hepatocellular carcinoma, 15 metastatic carcinoma, 10 with amoebic liver abscess, 10 with cirrhosis and 10 normal individuals at King Edward VIII Hospital, Durban. A cutt-off value of 10 u/ml was used. The sensitivity and specificity of CA-195 in hepatocellular carcinoma and metastatic carcinoma was 60% and 22%, and 87% and 42% respectively. False positive results occurred in 5 (50%) patients with amoebic liver abscess, 10 (100%) with cirrhosis and 2 (20%) normal individuals. These results indicate this tumor marker as of limited value in the diagnosis of hepatocellular carcinoma and metastatic carcinoma, and in distinguishing between these conditions.

Changes in myocardial electrolytes and ventricular fibrillation threshold induced by alcohol feeding in laboratory rats

Three groups of rats were studied in an investigation to determine the influence of alcohol on myocardial electrolytes and the ventricular fibrillation threshold (VFT) levels. Drinking water was provided ad libitum; the control group received water while the other 2 groups drank a water-ethanol solution, constituted in a ratio of 75: 25, for periods of 3 and 9 months, respectively. Two rats from each of the experimental groups, together with a control rat were killed on each experimental day. One heart was studied on the Langendorff preparation and the other used for tissue electrolyte analysis. The mean myocardial Mg2+ levels (233 +/- 28 micrograms/g vs 148 +/- 23 micrograms/g and 233 +/- 28 micrograms/g vs 107 +/- 15 micrograms/g; p less than 0.0001), K+ levels (3260 +/- 437 micrograms/g vs 1779 +/- 312 micrograms/g and 3260 +/- 437 micrograms/g vs 1195 +/- 205 micrograms/g; p less than 0.0001) and Zn2+ levels (32.7 +/- 6.8 micrograms/g vs 14.0 +/- 4 micrograms/g and 32.7 +/- 6.8 micrograms/g vs 4.2 +/- 3.4 micrograms/g; p less than 0.0001) were significantly lower in alcohol fed rats than the controls. In addition, a significant fall in the mean VFT levels (10.1 +/- 1.94 mA vs 6.27 +/- 2.17 mA, p less than 0.001) was noted in rats given water: alcohol solution for 9 months. This study reveals that chronic exposure to alcohol induces a deficiency of myocardial Mg2+, K+ and Zn2+, and an increase in myocardial irritability in laboratory rats.

'Tru-Cut' needle biopsy of the liver: importance of the correct technique

In order to determine which technique would provide adequate tissue for histological examination when the 'Tru-Cut' needle is used for liver biopsy, the livers of cadavers were biopsied by a single operator, under direct vision, using a 'Tru-Cut' needle. The modified breast biopsy technique either preceded or followed one of two alternative methods, one of which was recommended by the manufacturer, in a random manner. Thereafter, the biopsies were repeated using the alternative sequence. The mean length of the liver biopsy specimens that were obtained using the modified breast biopsy technique was 16.3 mm (range: 8-20 mm). The corresponding figures for the manufacturerer's method were 7.7 mm (range: 2-14 mm) and for the third technique were 2.7 mm (range: 0.5-8 mm). Three of the 40 specimens (7.5%) obtained using the latter technique fragmented when placed in formalin; this did not occur in any of the 40 specimens taken using the modified breast biopsy technique. This investigation indicates that the modified breast biopsy technique should be used when 'Tru-Cut' needle biopsy of the liver is performed. This provides specimens which are adequate for histological diagnosis. In addition, the safety of liver biopsy, which is compromised by poor technique, is improved. The alternative methods, including that recommended by the manufacturer, must be avoided.

Time course of the blood pressure response to oral isradipine in uncomplicated mild-to-moderate essential hypertension

Forty-five patients with supine diastolic blood pressures (DBPs) above 95 mm Hg at the end of a four-week placebo run-in period were randomized to receive either 1.25 mg, 2.5 mg, or 5 mg isradipine twice daily as monotherapy for 12 weeks. Blood pressures (BP) were measured every 14 days, always by the same observer and using standard techniques. The Montevideo Mathematical Model was used to determine the time course of the response to treatment in each dosage group. Of the 33 patients who completed the study, four of the 12 patients receiving 1.25 mg isradipine twice daily had their BP controlled by weeks 10 or 12 (supine DBP less than or equal to 90 mm Hg), seven of 11 by 2.5 mg twice daily, and five of 10 by 5 mg twice daily. Mean DBPs for each dosage group were significantly reduced by week 12 (P less than .015 in all groups). The Montevideo Model allows estimation of the time after onset of treatment by which BP is reduced by a given amount. This model indicated that, with 2.5 mg isradipine twice daily, a fall in mean arterial pressure of 10 mm Hg is to be expected within three weeks of initiating drug administration.

Comparison of felodipine and hydrochlorothiazide for the treatment of mild to moderate hypertension in black Africans

A double-blind, parallel-group study was performed to assess the antihypertensive effects and tolerability of felodipine and hydrochlorothiazide (HCT) in black patients with mild to moderate uncomplicated hypertension [entry supine diastolic blood pressure (DBP) of 96-116 mm Hg]. The medicines were given as monotherapy and the additional effect of metoprolol was assessed in patients unresponsive to felodipine or HCT alone. After a 4-week placebo period, 45 patients were randomly allocated to treatment with felodipine (21) or HCT (24). Initial doses of felodipine 2.5 mg or HCT 12.5 mg twice daily were doubled after 1 week and doubled again after week 4 in cases with supine DBP above 90 mm Hg. At week 8, metoprolol 100 mg twice daily was added to the regimen of uncontrolled patients (supine DBP greater than 90 mm Hg) and maintained for the remaining 4-week trial period. Felodipine significantly reduced supine and erect systolic BP (SBP) and DBP after 4, 8, and 12 weeks of treatment. Responses to HCT were similar although standing diastolic BP at week 4 and standing SBP at week 8 were not significantly reduced. After 4 weeks, the mean fall in supine DBP was significantly greater for the felodipine than the HCT group. Eight patients on felodipine and 14 in the HCT group required additional metoprolol to achieve BP control. A significantly greater number of adverse effects were associated with HCT than felodipine treatment. Monotherapy with felodipine produced a more rapid control of hypertension, was more frequently effective, and was associated with a lower incidence of side effects than HCT.

Ultrasonography and scintigraphy in liver disease in developing countries. A retrospective survey

In a study of the value of hepatic ultrasonography (US) and scintigraphy (SG) in detecting liver disease in developing countries 425 US scans and 304 SG scans of patients with focal or diffuse liver disease or normal livers were reviewed. The accuracy of both US and SG in distinguishing between normal and diseased livers was low (68% and 74%, respectively). Both techniques did better at detecting focal than diffuse liver disease; the sensitivity of US and SG in focal and diffuse disease was 88% and 92%, and 27% and 54%, respectively. The specificity of both procedures was high for both types of liver disease (91-96%). Overlap between US features of amoebic liver abscess, hepatocellular carcinoma, and metastatic carcinoma resulted in a correct final diagnosis being made in only 81% of patients with amoebic liver abscess, 29% with hepatocellular carcinoma, and 43% of patients with metastatic carcinoma who had a US scan. This study indicates that these techniques are neither accurate in detecting diffuse liver disease nor capable of determining the cause of diffuse liver disease. When diffuse parenchymal liver disease is suspected biopsy would be needed. Although the accuracy of both imaging modalities in detecting focal disease is high, overlap between the US features of the common causes of space-occupying lesions may result in an incorrect final diagnosis in some cases. In consequence, biopsy or aspiration might be required.

HLA-A, B, DR, and DQ antigens in black patients with severe chronic rheumatic heart disease

To determine whether genetic factors could be involved in the pathogenesis of rheumatic heart disease, we performed HLA-A and HLA-B typing in 120 black patients with severe chronic rheumatic heart disease requiring cardiac surgery, and HLA-DR and HLA-DQ typing in 103 and 97 of these patients, respectively. The HLA typing was done by a standard microlymphocytotoxicity method. Patients were 12 to 60 years old (mean 27.6 +/- 14.5). No differences in HLA-A, HLA-B, and HLA-DQ frequencies between patients and controls were noted. HLA-DR 1 antigen was present in 12.6% of patients compared with 2.7% of normal control subjects (corrected p less than .045; relative risk = 5.2) and the HLA-DRw6 antigen was present in 31.1% of patients compared with 15% of control subjects (corrected p less than .045; relative risk = 2.6). These findings suggest that genetically determined immune-response factors may play a role in the pathogenesis of severe chronic rheumatic heart disease.

The conservative management of amoebic liver abscess complicated by thoracic extension

We report the successful use of a conservative regimen in the management of amoebic liver abscess with thoracic spread and present two illustrative case reports.

A prospective study of hepatic tuberculosis in 41 black patients

Forty-one black patients aged 21 to 75 years with hepatic tuberculosis diagnosed at liver biopsy were studied prospectively. The liver varied in size and consistency and was tender in 44 per cent of patients. Abdominal symptoms, weight loss, pyrexia, hepatomegaly, splenomegaly and anaemia were absent in 54, 39, 37, 5, 68 and 27 per cent of patients respectively. Twenty-two per cent of chest radiographs were normal. Liver function tests were of little diagnostic value and hepatic imaging techniques often gave normal results. Acid-fast bacilli, caseation and coexistent liver disease were detected in 59, 51 and 37 per cent of patients respectively. Since there was no consistent clinical pattern a high index of suspicion is necessary if this disease is to be detected in communities in which tuberculosis is endemic. In patients with unexplained hepatomegaly or hepatosplenomegaly or pyrexia of unknown origin liver biopsy provides the only means of making this diagnosis.

Pulmonary alveolar proteinosis. A case report

An indian woman with pulmonary alveolar proteinosis whose symptoms, chest radiograph and pulmonary function tests remain unchanged 3 years after diagnosis is described. A brief discussion of this rare disease is also presented.

Carcinoma of the prostate with multiple osteolytic metastases simulating multiple myeloma. A case report

A patient with multiple osteolytic metastases--ribs, pelvis, spine, skull and mandible--from carcinoma of the prostate is described.

Sampling variability and its influence on the diagnostic yield of percutaneous needle biopsy of the liver

In an investigation to determine the influence of sampling variability on the diagnostic yield of liver biopsy, 3 consecutive samples were obtained from each of 75 patients by redirecting the biopsy needle through a single entry site. In 14.7% of patients all 3 specimens were normal, and in 36% there were similar abnormalities in all 3 specimens. In the other patients, sampling variability between specimens was present. In those patients with cirrhosis, hepatocellular carcinoma, metastatic carcinoma, or hepatic granulomas the histological abnormality was present in all 3 biopsy specimens in only 50%, 54.5%, 50%, and 18.8% of patients, respectively. No complications were recorded. These findings show that important pathology can be overlooked if only a single biopsy specimen is taken, and that the method of obtaining 3 consecutive specimens improves the diagnostic yield of liver biopsy without an associated increase in complications.

Causes of hepatomegaly at King Edward VIII Hospital, Durban. A prospective study of 240 black patients

In this prospective study of 240 black patients with liver enlargement admitted to the medical wards of King Edward VIII Hospital, Durban, a cause for the hepatomegaly was found in 92.5% of cases (63.8% without recourse to biopsy, 28.7% after liver biopsy). The commonest cause was congestive heart failure (36.7%), followed by amoebic liver abscess (7.1%), hepatocellular carcinoma (5.8%) and cirrhosis (5.4%). Liver biopsy provided the diagnosis in 90.8% of patients with initial unexplained hepatomegaly. The diagnostic yield of liver biopsy was increased by submitting 3 biopsy specimens for histological examination. The 3 specimens are obtained using a single intercostal entry site and redirecting the biopsy needle, without increasing the risk of complications. Hepatic tuberculosis was present in 9.2% of patients who underwent biopsy. There were no consistent clinical findings in these patients. Therefore, in communities in which tuberculosis is endemic, all patients with unexplained hepatomegaly require liver biopsy since it provides the only means of making this diagnosis.

Captopril once daily in patients with essential hypertension and hyperuricaemia

Captopril (Capoten; Squibb) 100 mg was given as once-daily monotherapy in 20 patients with hypertension and hyperuricaemia. Ten patients (group A) maintained a low-sodium diet (60-100 mmol/d) throughout the study and 10 (group B) continued their usual high-sodium (200-300 mmol/d) diet. After 4 weeks of active treatment supine blood pressure in group A decreased from 192 +/- 5/119 +/- 3 mmHg to 144 +/- 3/95 +/- 3 mmHg (P less than 0,001), whereas pressures in group B varied between 168 +/- 5/115 +/- 3 mmHg and 160 +/- 6/113 +/- 4 mmHg (not significant). Serum urate values fell from 0,46 +/- 0,02 mmol/l to 0,35 +/- 0,02 mmol/l (P less than 0,001) and 0,53 +/- 0,02 mmol/l to 0,46 +/- 0,03 mmol/l (P less than 0,05) in the same groups. Captopril exerted an antihypertensive effect in patients receiving a low-sodium diet, suggesting a relationship with angiotensin II and/or aldosterone; effects on serum urate levels appeared to be independent of diet.