Summary The prevalence (lifetime occurrence) rate of cancers of the reproductive system (uterus, ovary, cervix and vagina) and breast cancer was determined for 5,398 living alumnae, 2,622 of whom were former college athletes and 2,776 non-athletes, from data on medical and reproductive history, athletic training and diet. The former athletes had a significantly lower risk of cancer of the breast and reproductive system than did the non-athletes. The relative risk (RR), non-athletes/athletes, for cancers of the reproductive system was 2.53. 95% confidence limits (CL) (1.17, 5.47 This study was suggested by the findings that strenuous exercise delays menarche (Frisch et al., 1980;Warren, 1980;Frisch et al., 1981) and that women dancers and athletes, including college athletes, have a high incidence of oligomenorrhoea and secondary amenorrhoca (Frisch et al., 1981;Dale et al., 1979;Frisch et al., 1980
The relative importance of regulatory versus structural evolution for the evolution of different biological systems is a subject of controversy. The primacy of regulatory evolution in the diversification of morphological traits has been promoted by many evolutionary developmental biologists. For physiological traits, however, the role of regulatory evolution has received less attention or has been considered to be relatively unimportant. To address this issue for electrophysiological systems, we examined the importance of regulatory and structural evolution in the evolution of the electrophysiological function of cardiac myocytes in mammals. In particular, two related phenomena were studied: the change in action potential morphology in small mammals and the scaling of action potential duration across mammalian phylogeny. In general, the functional properties of the ion channels involved in ventricular action potential repolarization were found to be relatively invariant. In contrast, there were large changes in the expression levels of multiple ion channel and transporter genes. For the Kv2.1 and Kv4.2 potassium channel genes, which are primary determinants of the action potential morphology in small mammals, the functional properties of the proximal promoter regions were found to vary in concordance with species-dependent differences in mRNA expression, suggesting that evolution of cis-regulatory elements is the primary determinant of this trait. Scaling of action potential duration was found to be a complex phenomenon, involving changes in the expression of a large number of channels and transporters. In this case, it is concluded that regulatory evolution is the predominant mechanism by which the scaling is achieved.
To varying extents, women with pre-existing cardiomyopathies have a limited cardiovascular reserve. The hemodynamic challenges of pregnancy, labor, and delivery pose unique risks to this group of patients, which can result in clinical decompensation with overt heart failure, arrhythmias, and rarely, maternal death. A multidisciplinary team approach and a controlled delivery are crucial to adequate management of patients with underlying heart disease. Pre-conception planning and risk assessment are essential, and proper counseling should be offered to expectant mothers with regard to both the risks that pregnancy poses and the implications for future offspring. In this article, we will review the hemodynamic stressors that pregnancy places upon women with pre-existing cardiomyopathies and risk assessment and discuss what evidence exists with regard to the management of 2 forms of cardiomyopathy during pregnancy, labor, and delivery: dilated and hypertrophic cardiomyopathy.
A mother and son had an autosomal-dominant malformation syndrome that included absence of the lacrimal puncta, obstruction of the nasolacrimal ducts, hearing loss, poor dentition, and abnormal thumbs. The son also had severe hypertension with renal anomalies and absence of several salivary glands. Affected members of the only other reported family also had cup-shaped ears and synostosis of the radius and ulna. Early recognition of this disorder is important because of the possibility that the affected infant may have hearing loss and kidney malformations.
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