A comparison of two bipolar exercise electrocardiographic leads to lead V5

ST-segment depression and slope were compared in three lead systems (V5, CC5, and CM5) and in two groups of patients using both visual analysis of electrocardiographic paper and computerized techniques. Bipolar lead CC5 was found to be comparable to lead V5 when visual analysis of electrocardiographic recordings was utilized. Bipolar lead CM5 was found not to be comparable to lead V5 and to be less sensitive if classic criteria for slope were used. The technique of computerized analysis mad measurements of slope and amplitude to a reproducible level not possible with the standard technique. Statistically significant differences were found between the exercise electrocardiographic leads utilizing computerized electrocardiographic analysis . We conclude that computerized techniques of electrocardiographic analysis require new criteria for defining an abnormal repolarization response. The criteria must be specific for different electrocardiographic leads if the repolarization changes in these leads are to have comparable diagnostic significance.

The effects of neonatal vestibular stimulation on adult growth and emotional reactivity in BALB/c mice

Two experiments were conducted to determine the effects of neonatal vestibular stimulation on the subsequent development and behavior in BALB/c mice. No evidence appeared to suggest that neonatal vestibular stimulation alters either the growth pattern or the ontogenesis of emotional reactivity.

Metabolic effects of parathyroidectomy in asymptomatic primary hyperparathyroidism

Effects of parathyroidectomy on parathyroid function and calcium (Ca) metabolism were carefully evaluated in 6 patients with primary hyperparathyroidism without symptoms normally attributed to the disease and in 7 with bone disease or nephrolithiasis. Before parathyroidectomy, both groups of patients demonstrated evidence of the sequelae of parathyroid hormone (PTH) excess, since they presented one or more of the following features: low bone density by 125I-photon absorption, hypercalciuria (urinary Ca greater than 200 mg/day on an intake of 400 mg/day), negative Ca balance (absorbed Ca less than urinary Ca), elevated fasting urinary Ca greater than 0.2 mg/mg creatinine for a night-time sample after a 6-hour fast), and decreased renal function (creatinine clearance of less than 65 ml/min). Following parathyroidectomy, most of these deleterious effects were reversed commensurate with the return of immunoreactive serum PTH, serum Ca, and urinary cyclic AMP toward normal. These quantitative non-invasive techniques may be useful for the initial evaluation and follow-up of patients with asymptomatic primary hyperparathyroidism.

Photon absorptiometric analysis of bone density in primary hyperparathyroidism

The density of bone in the distal third of the radius was measured in 13 men and 17 women with primary hyperparathyroidism. The bone density was significantly reduced (as compared to age-matched controls) in 7 of 11 postmenopausal women. However, it was reduced in only 2 of 13 men and in 1 of 6 premenopausal women. Thus, most of the postmenopausal women with primary hyperparathyroidism had low bone density, whereas most men and premenopausal women with this condition had normal bone density. The results support the conclusion that oestrogen deficiency may contribute to the development of bone disease by sensitising bone to the action of parathyroid hormone.

Infant leukaemias and cot deaths

Infant leukaemias differ from childhood leukaemias in ways which suggest that when haemopoietic neoplasms combine fetal origins with rapid growth rates they prevent normal development of the reticuloendothelial system and thus cause the sudden death of apparently healthy babies (stillbirths or cot deaths). Cot deaths are commoner in boys and have a peak incidence during the first half of infancy-that is, during the period most affected by the switch from passive to active immunity. Babies born from July to December, who are intensively exposed to winter conditions form 1 to 5 months of age, are also at special risk. During this period more girls and more children born form January to June die of leukaemia; and within three months of birth an exceptionally high ratio of myeloid to lymphatic leukaemias has been replaced by a low ratio, which persists throughout childhood.

Malignant lymphomas of African children

Clinical, pathologic, and epidemiologic observations of malignant tumors of children in sub-Sahara Africa suggest alternative theories of causation, and give insight into environmental influences that may play a large role in the etiology and form of malignant lymphatic tumors and cerebral neoplasms of infants.