This study was designed to determine whether oestrogens in oral contraceptives and other drugs have a protective effect against development of rheumatoid arthritis. The medical records of 229 women with rheumatoid arthritis and 458 individually matched controls identified through the comprehensive records system for the population of Rochester, Minnesota, were examined for current and prior use of oestrogens. No association was found between rheumatoid arthritis and the use of oral contraceptives, or the use of oestrogens for menopause-related or postmenopausal symptoms.

A randomised study of 189 deliveries was conducted to compare performance in the conventional dorsal position with that in a birth chair. There was no significant difference in the length of the second stage of labour, the time spent bearing down, or the need for operative delivery. Overall blood-loss was greater among patients delivered in the chair but more of this group had either an intact perineum or only superficial damage. The condition of the neonates in the two delivery groups was similar.

Objective evidence of food hypersensitivity was sought by the use of exclusion diets and provocation tests in 23 patients who attributed a wide variety of symptoms to food allergy. Hypersensitivity to ingested substances was confirmed in 4, each of whom presented with typical atopic symptoms. None of these had psychological symptoms, but a high incidence of psychiatric disorder was found in patients whose belief that they had a food allergy could not be confirmed.

Oral bromocriptine (1.25 mg) was given to 8 healthy volunteers in a double-blind placebo controlled cross-over study. 3 and 4 h after taking the tablet there was a significant reduction in intraocular pressure but no change in pupil diameter. There were no changes in heart rate, blood pressure, and systolic time intervals in 6 other healthy volunteers within 3 h of being given 1.25 mg bromocriptine. These results suggest that dopamine receptors may be involved in the control of intraocular pressure.

Urinary prostacyclin (PGI2) was measured in 12 chronic smokers and 12 non-smokers after inhalation of smoke from nicotine-containing and nicotine-free cigarettes. In a separate study a pressor dose of noradrenaline, which increases PGI2, was given to smokers and non-smokers. PGI2 was measured as the stable metabolite, 6-keto-PGF1 alpha in 4 h urine samples by radioimmunoassay after chromatography on LH-20 'Sephadex'. Smoking of nicotine-free cigarettes had no effect on PGI2 release in either smokers or non-smokers. In non-smokers inhalation of nicotine-containing tobacco smoke increased heart-rate, blood-pressure, and urine osmolality, but did not affect urinary 6-keto-PGF1 alpha. In contrast, when chronic smokers used nicotine-containing cigarettes there was a highly significant reduction in excretion of 6-keto-PGF1 alpha (192 +/- 20 to 138 +/- 17 ng/g creatinine). Noradrenaline increased PGI2 in non-smokers (181 +/- 16 to 348 +/- 56) but not in smokers. Smoking of nicotine-containing tobacco abolished the PGI2 response to noradrenaline. These observations suggest that inhalation of nicotine-containing tobacco smoke reduces vascular PGI2 production; this may be a factor in the development of accelerated cardiovascular disease.

78 patients with bacterial meningitis were evaluated in a prospective, randomised study comparing twice-daily ceftriaxone as single-drug therapy with ampicillin and chloramphenicol given every 6 h. The groups were comparable in age, sex, days of illness before admission, and bacterial colony counts in cerebrospinal fluid (CSF). The pathogens were Haemophilus influenzae type b (54 cases), streptococci (9 cases), meningococci (9 cases), and unknown (6 cases). In 40 CSF specimens obtained 4-12 h after initiation of therapy, cultures were negative in 57% of the ceftriaxone patients and in 42% of the others. The mean falls in the CSF bacterial colony counts were 4.7 and 5.0 log10 colony-forming units/ml, respectively. Mean bactericidal activity in CSF was significantly greater in the ceftriaxone than in the conventional treatment group at the beginning and end of therapy. There were no significant differences in clinical responses or in frequency of complications, except for mild diarrhoea, which occurred in 16 ceftriaxone patients and in 8 in the other group (p less than 0.05).

Cervical injury is one of the most frequent complications of suction curettage abortion, yet little is known about its risk factors or prevention. In 15 438 suction curettage abortions carried out at less than or equal to 12 weeks' gestation in hospitals in the USA from 1975 to 1978 the incidence of cervical injury requiring suturing was 1.03 per 100 abortions. Among factors potentially within the physician's control, use of laminaria rather than rigid dilators for dilatation had a strong protective effect (relative risk 0.19), whereas performance of the abortion by a resident rather than an attending physician (relative risk 2.0) and use of general rather than local anaesthesia (relative risk 2.6) had detrimental effects on rates of cervical injury. Among other factors, a previous abortion had a protective effect (relative risk 0.46), whereas patient age less than or equal to 17 years had a detrimental effect (relative risk 1.9). Use of laminaria, performance of the abortion by an attending physician, and local anaesthesia together yield a 27-fold protective effect.

28 patients who had a sustained diastolic blood pressure of 95 to 104 mm Hg and who had no treatment for it for at least 13 months before the trial, but who were otherwise unselected, took part in a randomised controlled trial in which the effect of a restricted sodium diet was compared with that of a general health package. The general health package did not include any specific hypotensive procedures. Changes in blood pressure were measured at predetermined intervals over the course of a year. Within each group both systolic and diastolic blood pressure fell to a highly significant extent after a year, but there was no significant difference between the groups. It would thus seem that the antihypertensive effect of a restricted sodium diet may be related to the increased consultation and monitoring activity of such intervention rather than to the dietary manipulation itself.

To determine whether advertising by infant formula companies shortens the duration of breast-feeding, we randomly assigned 448 breast-feeding new mothers to either receive or not receive a formula sample packet upon discharge from a maternity ward. These mother, unaware of the study, were then telephoned 3 months post partum by a research assistant blind to the randomisation status. "Sample" mothers were less likely to still be breast-feeding at 1 month (78% vs 84%, p = 0.07) and more likely to have introduced solid foods by 2 months (18% vs 10%, p = 0.01). These trends became more significant in three vulnerable subgroups: less educated mothers, primiparas, and mothers who had been ill post partum. Our results suggest that infant formula samples may shorten the duration of breast-feeding and hasten the age at which solids are introduced.

254 patients with serious gram-negative bacillary infections were enrolled into a multicentre, randomised, blind clinical trial and treated with tobramycin-ticarcillin or netilmicin-ticarcillin. The two treatment groups were similar as to sex, age, and weight. The mean daily dose of netilmicin (237 mg) was higher than that of tobramycin (211 mg), p less than 0.01, but the mean duration of therapy was longer with tobramycin (9.4 days versus 8.7 days), p less than 0.01. The netilmicin cohort also had more serious underlying diseases, p less than 0.028. Clinical (tobramycin, 93% and netilmicin, 91%) and bacteriological responses (tobramycin, 87% and netilmicin, 89%) were similar. 84 tobramycin and 73 netilmicin patients had serial audiograms. Eighth nerve deficits developed in 10 (12%) tobramycin and two (3%) netilmicin patients, p = 0.037. Drug-related renal dysfunction developed in 5 (4%) of 114 tobramycin patients whose renal function was monitored and in 1 (1%) of 116 netilmicin patients, p = 0.12.

Results are presented from the Belgian Heart Disease Prevention Project, part of the WHO European Collaborative Trial in the Multifactorial Prevention of Coronary Heart Disease (CHD). 19 409 men aged 40-59 yr took part; they were employed in thirty factories which formed the allocation units for a randomised controlled trial lasting 5-6 yr. The intervention package consisted largely of health education promoting a cholesterol-lowering diet, smoking cessation, weight control, physical activity, and treatment of arterial hypertension. A programme of information was supplemented by face-to-face counselling at the workplace by two physicians attached to the project. The coronary risk profile was reduced in the intervention group, compared with that in the control group, especially during the first 4 yr, by effects on serum cholesterol, number of cigarettes smoked daily, and arterial blood-pressure. Total mortality was 17.5% lower in the intervention group than in the control group (p = 0.038). Coronary mortality was reduced by a non-significant 20.8% whereas CHD incidence (non-fatal myocardial infarction plus fatal myocardial infarction plus sudden deaths) was reduced by 24.5% (p = 0.031). Non-fatal myocardial infarction (not a major end-point) was similarly reduced by 26.1% (p = 0.030).