Horm Res
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Hypocalcemic cardiomyopathy due to hypoparathyroidism is a very rare condition which is usually refractory to conventional treatment for cardiac failure but which responds favorably to restoration of normocalcemia. A 55-year-old man and a 46-year-old woman with a history of postoperative hypoparathyroidism presented with symptoms of cardiac failure and hypocalcemia. ⋯ The coronary angiograms were normal and there was no apparent cause for dilated cardiomyopathy in these patients. The history of the patients and partial recovery of cardiac function after restoration of normocalcemia suggest that hypocalcemia was the cause of dilated cardiomyopathy.
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In a previous cross-sectional pilot investigation, an increase in the ratio of active cortisol to inactive cortisone in serum has been found as a general phenomenon during the acute-phase response. The aim of the present study was to further characterize this alteration of cortisol metabolism in patients undergoing elective cardiac bypass surgery. ⋯ Following major surgery, the substantial increase in the serum cortisol:cortisone ratio - reflecting a shift in the overall set-point of 11beta-hydroxysteroid dehydrogenase activity - is more sustained than the increase in serum cortisol; the increase in the cortisol:cortisone ratio seems to be a long-term phenomenon of the activation of the hypothalamic-pituitary-adrenocortical system by surgical stress and systemic inflammation.
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The most potent corticosteroids are 11beta-hydroxylated compounds. In humans, two cytochrome P450 isoenzymes with 11beta-hydroxylase activity, catalysing the biosynthesis of cortisol and aldosterone, are present in the adrenal cortex. CYP11B1, the gene encoding 11beta-hydroxylase (P450c11), is expressed on high levels in the zona fasciculata and is regulated by ACTH. ⋯ Molecular genetic studies are complementary; on the one hand, they have practical importance for the prenatal diagnosis of virilizing CAH forms and on the other hand, they are of theoretical importance in terms of our understanding of the functioning of cytochrome P450 enzymes. Copyrightz1999S. KargerAG, Basel
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Insulin-like growth factor (IGF)-I is an important mitogen required by some cell types to progress from the G1 phase to the S phase of the cell cycle. IGF binding proteins (IGFBPs) can have opposing actions, in part by binding IGF-I, but also by direct inhibitory effects on target cells. As mitogens and anti-apoptotic agents, IGFs may be important in carcinogenesis, possibly by increasing the risk of cellular transformation by enhancing cell turnover. ⋯ Of note, for colorectal neoplasia, fourfold elevated risks were observed in men and women with low IGFBP-3, whereas high IGF-I was associated with a doubling of risk. These emerging epidemiologic data indicate that high levels of IGF-I and low levels of IGFBP-3 are associated with an increased risk of at least several types of carcinoma that are common in economically developed countries. Further study is required to determine the clinical relevance of these findings.
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The goals of this presentation are to review the essential roles of aromatase, estrogens and the estrogen receptor in pubertal growth. Estrogen deficiency due to mutations in the aromatase gene (CYP19) and estrogen resistance due to disruptive mutations in the estrogen receptor gene have no effect on normal male sexual maturation in puberty. However, they lead to absence of the pubertal growth spurt, delayed bone maturation, unfused epiphyses, continued growth into adulthood and very tall adult stature in both sexes. ⋯ In conclusion, estrogens are essential for normal female secondary sexual maturation, bone maturation, epiphyseal fusion, pubertal growth spurt and achievement of normal bone mineral mass. Estrogens also influence insulin sensitivity and lipid homeostasis. However, estrogens do not appear to be essential for fetal survival, placental growth, or female sexual differentiation.