In 414 volunteers the sensitivity and specificity of a multipuncture skin test with excretory-secretory (ES) toxoplasma antigen was compared with serological detection by an indirect fluorescent antibody (IFA) test. The ES antigen was extracted from supernatants of cell cultures infected with Toxoplasma gondii, purified, and standardised, and the antigen used met current safety standards. The correlation between the skin test and IFA result was 94.2% (97.8% when the skin test was repeated 30 days later). No false-positive skin tests were noted. The skin test did not transform an originally negative serological test into a positive one. In programmes to prevent congenital toxoplasmosis, this sensitive, specific, and inexpensive skin test can be widely used for the detection of immunity to toxoplasma in women before their first pregnancy.

A randomised double-blind intervention trial was carried out in Huixian, Henan Province, People's Republic of China, to determine whether combined treatment with retinol, riboflavine, and zinc could lower the prevalence of precancerous lesions of the oesophagus. 610 subjects in the age group 35-64 were randomised to receive once a week the active treatment (15 mg [50 000 IU] retinol, 200 mg riboflavine, and 50 mg zinc) or placebo. Both at entry to the study and at the end of the treatment, 13.5 months later, the subjects were examined, with an emphasis on signs of vitamin A and riboflavine deficiences, and riboflavine, retinol, beta-carotene, and zinc levels were measured. Compliance was excellent. The final examination, on 567 (93%) subjects, included oesophagoscopy and at least two biopsies. The intervention did not affect the prevalence of oesophageal lesions: after one year, the prevalence of oesophagitis with or without atrophy or dysplasia was 45.3% in the placebo group and 48.9% in the vitamin/zinc treated group.

In a crossover study of 26 hypertensive patients, the effects of triamterene (50 mg/day) and amiloride (5 mg/day) on urinary sediment were compared. Each drug was given for one month and all patients also received hydrochlorothiazide (50 mg/day). An abnormal urinary sediment--evident grossly as a reddish-brown precipitate after routine staining procedures and microscopically as characteristic reddish-brown crystals and casts, as previously described--was identified in 14 of 26 (54%) triamterene urine samples but in none of the amiloride samples. Results of renal function tests were similar for both drugs. In a clinic population of more than 1000 hypertensive patients over 4 years, interstitial nephritis was diagnosed in 4, all of whom were taking a triamterene-containing combination diuretic. It is possible that triamterene is a factor in the aetiology of interstitial nephritis.

101 (68%) of 148 dyslexic children had unstable vergence eye movement control (unfixed reference) in the Dunlop synoptophore test. These children tended to make visual rather than phonemic errors when reading and writing; the opposite was true for those with stable control (fixed reference). The 148 dyslexic children were given plano spectacles to wear for 6 months when reading and writing and were randomised to receive either spectacles that had the left lens occluded or untreated ones. The trial was double blind. Conversion from unfixed to fixed reference occurred in 51% of the children who wore occluded spectacles, compared with 24% of those who wore plain spectacles. In the former group increase in reading ability improved by almost 6 months relative to change in age, whereas in those who wore plain spectacles and whose reference did not become fixed reading ability regressed by 0.4 months. The children with unfixed reference who did not benefit from occlusion were those who made not only visual but also phonemic and sequencing errors. Monocular occlusion may thus help one-sixth of dyslexic children to develop reliable vergence control and thereby to read.

The prophylactic effect of antibody to endotoxin core glycolipid was studied in surgical patients at high risk of gram-negative infection. At randomisation (on admission to intensive care unit), every 5 days thereafter, and at onset of septic shock, patients received plasma taken from donors before (control) or after immunisation with Escherichia coli J5, a mutant with only core determinants in its endotoxin. Gram-negative shock occurred in 15 of 136 controls and 6 of 126 J5 antibody recipients and related deaths in 9 of 136 and 2 of 126, respectively. J5 antibody was most effective in abdominal surgery patients, in whom shock occurred in 13 of 83 controls and 2 of 71 antibody recipients. Although antibody prophylaxis did not lower the infection rate, it prevented the serious consequences of gram-negative infections and thus improved the overall prognosis.

In-vitro and animal studies have shown that viral agents can be removed from or inactivated in clotting factor concentrates by physical or chemical treatment. However, clinical data have as yet not substantiated the results of these studies. 13 haemophilia A patients who had not been treated previously with blood or blood products were given a dry-heated factor VIII concentrate and were tested serologically over the next 12 months. Hepatitis developed in 11 patients (84%) and was invariably of type non-A, non-B. Morbidity was not related to the lot of the therapeutic material or to the number of infusions. The incubation period was either 5 or 8-11 weeks, and only 1 patient had symptoms. Aminotransferase elevation showed both monophasic and biphasic patterns. During the follow-up period signs of the disease disappeared in 10 patients (90%). These findings contrast with the absence of non-A, non-B hepatitis in chimpanzees given the same heated concentrate. Thus, clinical studies in first-exposure haemophiliacs are essential for the true evaluation of the safety of new "treated" concentrates.

Biodegradable polylactide-glycolide copolymer implants for fracture fixation were developed and tested in rabbits. In a prospective clinical study 44 patients with a displaced fracture of the ankle were randomly allocated to two groups; one was treated with conventional metallic implants and the other with the biodegradable implants. There were no differences between the two groups in the early results, but the biodegradable fixation method is advantageous because the removal procedure associated with metallic implants is avoided.

Treatment of septic shock with naloxone was evaluated in a prospective, randomised, double-blind, placebo-controlled study in which ten episodes of shock were treated with naloxone (0.4 to 1.2 mg intravenously) and 13 with the vehicle for injection. Treatment groups were similar in terms of demographic characteristics, type of primary infection, prevalence of septicaemia, type of underlying disease, duration in shock, and vasopressor therapy. Mean systolic blood pressure rose by 13.3% in the naloxone group and 11.3% in the placebo group. Two-way analysis of variance for repeated measures of blood pressure, obtained over 30 min periods before and after treatment, revealed no significant difference (p greater than 0.10) between treatment groups. Survival rates in the two groups at 48 h and 7 days after the start of treatment were similar. Naloxone, 0.4 to 1.2 mg intravenously, was no better than placebo in ameliorating hypotension in septic shock.

A double-blind randomised placebo-controlled trial of antihypertensive treatment was conducted in patients over the age of 60. Entry criteria included both a sitting diastolic blood pressure on placebo treatment in the range 90-119 mm Hg and a systolic pressure in the range 160-239 mm Hg. 840 patients were randomised either to active treatment (hydrochlorothiazide + triamterene) or to matching placebo. If the blood pressure remained raised, methyldopa was added to the active regimen and matching placebo in the placebo group. An overall intention-to-treat analysis, combining the double-blind part of the trial and all subsequent follow-up, revealed a non-significant change in total mortality rate (-9%, p = 0.41) but a significant reduction in cardiovascular mortality rate (-27%, p = 0.037). The latter was due to a reduction in cardiac mortality (-38%, p = 0.036) and a non-significant decrease in cerebrovascular mortality (-32%, p = 0.16). In the double-blind part of the trial, total mortality rate was not significantly reduced (-26%, p = 0.077). Cardiovascular mortality was reduced in the actively treated group (-38%, p = 0.023), owing to a reduction in cardiac deaths (-47%, p = 0.048) and a non-significant decrease in cerebrovascular mortality (-43%, p = 0.15). Deaths from myocardial infarction were reduced (-60%, p = 0.043). Study-terminating morbid cardiovascular events were significantly reduced by active treatment (-60%, p = 0.0064). Non-terminating cerebrovascular events were reduced (-52%, p = 0.026), but the non-terminating cardiac events were not (+3%, p = 0.98). In the patients randomised to active treatment there were 29 fewer cardiovascular events and 14 fewer cardiovascular deaths per 1000 patient years during the double-blind part of the trial.

120 patients were randomly allocated to receive ranitidine 150 mg twice daily or a tri-potassium di-citrato bismuthate (TDB) tablet four times a day in a trial comparing the effects of these drugs in the short-term healing and post-healing relapse rates of duodenal ulceration. At 4 weeks 81% of those on ranitidine and 90% of those on TDB had healed ulcer craters. At 8 weeks 97% of those on ranitidine and 97% of those on TDB had healed. These differences are not significant. After ulcer healing, the cumulative rates of relapse, as determined endoscopically, for symptomatic and symptomless ulcers were 74% for ranitidine and 41% for TDB at 4 months (p less than 0.001), 87% for ranitidine and 55% for TDB at 8 months (p less than 0.001), and 89% for ranitidine and 62% for TDB at 12 months (p less than 0.001). Females had significantly lower relapse rates than males. In the ranitidine group smokers had a higher rate of early relapse and failure to remain healed at 12 months than did non-smokers; no such difference occurred in the TDB-treated group.

The effectiveness of spinal manipulation carried out by a non-medical qualified osteopath was compared with that of short-wave diathermy (SWD) and a placebo (detuned SWD) in 109 patients with low back pain. More than half the subjects in each of the 3 treatment groups benefited immediately from therapy. Significant improvements were observed in the 3 groups at the end of 2 weeks' treatment, and these were still apparent at 12 weeks. The outcome of treatment was unrelated to the initial severity or duration of pain or to the trend of pain towards deterioration or improvement. It is, therefore, unlikely that the results simply reflect the natural history of low back pain. Benefits obtained with osteopathy and SWD in this study may have been achieved through a placebo effect.