The twenty-metre shuttle-running test: a combined test for maximal oxygen uptake and exercise-induced asthma?

A maximal multistage 'twenty-metre shuttle-running test' has already been developed to estimate maximal oxygen uptake (VO2 max). This field test requires little equipment or expertise, can be performed simultaneously by several subjects, and is widely used in physical education lessons. The present study assessed the potential for this test to provoke exercise-induced asthma in 73 schoolboys, aged 15-16 years. Measurements of the forced expiratory volume in one second (FEV1) were made at rest and 10 min after the twenty-metre shuttle-running test; exercise-induced asthma was defined as greater than a 10% fall in FEV1 after exercise. The pupils achieved 73 +/- 19 shuttles (mean +/- SD) giving a VO2 max of 47.0 +/- 5.3 ml kg-1 min-1. Exercise-induced asthma was documented in eight pupils (11%); two were known asthmatics who, despite taking pre-exercise B2 agonist treatment, had sharp falls in FEV1 (-25.4 and -25.6%); two had previously experienced occasional chest tightness or wheeze with exercise (-16.5 and -13.2% fall FEV1); but four were asymptomatic, with no previous asthmatic symptoms (-20.0, -18.2, -15.3 and -11.4% fall FEV1). This study has demonstrated the potential of the twenty-metre shuttle-running test to provoke exercise induced-asthma, and may therefore be a useful clinical test to assess for exercise-induced asthma when an estimate of VO2 max would also be helpful. Furthermore, physical education teachers should take basic precautions when using this test.(ABSTRACT TRUNCATED AT 250 WORDS)

Association between risk factors for coronary heart disease in schoolboys and adult mortality rates in the same localities.

Risk factors for coronary heart disease were compared in fifth year boys (15-16 years old) from two schools that were chosen from localities with a fourfold difference in adult mortality from coronary heart disease. One school was in an underprivileged urban locality in the area of increased incidence of heart disease ('high risk') and the other in a semi-rural affluent locality with an incidence of heart disease similar to the national average ('low risk'). Smoking, hypertension, hypercholesterolaemia, obesity, physical fitness, and inactivity were evaluated as risk factors for coronary heart disease. Smoking, increased body fat, poor diet, and physical inactivity were found increased among pupils from the school in the high risk area compared with those in the low risk area. Lipids, maximum oxygen uptake, and hypertension were similar in both schools. The risk of coronary heart disease seems to reflect the adult mortality rates in the area. To reduce the overall incidence of coronary heart disease, health education should be directed towards prevention of smoking, improving diets, and increasing amounts of activity among school children, with special attention directed toward children in regions where there is a high mortality from coronary heart disease among adults.

Congenital rubella affecting an infant whose mother had rubella antibodies before conception.

A woman who had had high titres of rubella antibodies some months before she became pregnant gave birth to an infant in whom congenital rubella was confirmed at 4 months. Rubella haemagglutination inhibition tests, complement fixation tests, and immunofluorescence tests with anti-human IgG were carried out on sera from the mother. Rubella antibody titres in sera obtained in March 1971, seven and a half months before conception, were equivalent to 400 units, which is usually taken as indicating good immunity. Rubella virus was isolated from the baby's nose and throat in July 1973 but was not isolated from a cervical swab taken from the mother in December 1973; tests of her immunological competence did not show any definite abnormality. The presence of high levels of rubella haemagglutination inhibition antibodies does not invariably confer immunity or exclude the possibility of congenital rubella in a subsequent pregnancy.

Persistent Truncus Arteriosus in a Dog.

A 5-week-old male mixed terrier with persistent truncus arteriosus had a grade IV cardiac murmur. Cardiovascular anomalies noted at necropsy included ventricular septal defect in addition to complete persistent truncus arteriosus. The latter originated from the right ventricle and served as an aorta, also providing aortic branches that included a modified bronchial artery. This malformation closely resembled type IV persistent truncus arteriosus in humans, however, anatomically it should be classified as type I because of a patent small hypoplastic pulmonary artery.