Biomedical subjects
Publications and source records attributed to R G Crilly.
The reduction of gonadotrophin levels, urinary calcium and hot flushes in post-menopausal patients by ethinyl oestradiol is shown to be dose dependent, near maximum response being achieved by a dose of 15 micrograms daily. Equivalent ethinyl oestradiol doses to a number of other gonadal hormone preparations have been assessed using the derived dose-response curve of the reduction in urinary calcium.
Histomorphometry has been applied to trabecular bone samples obtained post-mortem from young and old women without known bone disease and to bone biopsy specimens from patients with postmenopausal osteoporosis. Bone volume was significantly lower in the old than young controls and significantly lower again in the osteoporotics. The loss of bone with age associated with a rise in surface resorption but no change in forming surface, and the further loss in osteoporotics was associated with a further rise in resorption and a small non-significant fall in forming surfaces. It is suggested that trabecular bone volume is determined by the relation between total forming surface on the one hand and percent surface resorption on the other, and this relationship is expressed in mathematical terms. Age-related bone loss (simple osteoporosis) in women is accounted for by increased resorption, and accelerated osteoporosis is mainly due to a further increase in resorption.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Studies on post-menopausal osteoporotic patients indicate that 1,25-(OH)2 D3 concentrations are no different from those in age-matched normal subjects and the data suggest that the malabsorption of calcium found in many osteoporotic patients cannot generally be attributed to low plasma 1,25-(OH)2 D3 levels. The effects are discussed of three different therapies - sex hormones alone, vitamin D metabolites alone and a combination of both - on calcium balance and peripheral bone loss in treated compared with untreated osteoporotic patients. The results indicate that combined therapy with a vitamin D metabolite and an oestrogen is more effective in inhibiting the rate of bone resorption in post-menopausal osteoporosis than treatment with either agent used alone, and should be regarded as the treatment of choice at the present time. It is suggested that, using this regimen which is suitable for patients up to about 65 years of age, calcium supplementation is not required, provided daily calcium intake is reasonably adequate, and may even be undesirable by increasing the risk of hypercalcaemia.
Explore the source record for details and available documents.
Ninety-five postmenopausal women with unequivocably wedged or compressed vertebrae in whom the recognised causes of secondary osteoporosis had been excluded were studied, 41 having no treatment and the rest one or more of six different treatments. The treatment regimens comprised calcium supplements, vitamin D, calcium and vitamin D, ethinyloestradiol or--where oestrogens were contraindicated--norethisterone, 1 alpha-hydroxycholecalciferol (1 alpha-OHD3), or hormones with 1 alpha-OHD3. The seven groups were reasonably comparable in most respects except that the hormone-treated patients were younger and had a higher initial cortical area ratio than the others, and the calcium- and hormone-treated groups had the best initial radio-calcium absorption. The untreated osteoporotic patients lost cortical bone more rapidly than do normal postmenopausal women. Three treatments (calcium, hormones, and 1 alpha OHD3 plus hormones) appear to be useful in modifying the disease, and two treatments (vitamin D and 1 alpha-OHD3) useless or even harmful. Vitamin D and 1 alpha-OHD3 are more safely used in conjunction with oestrogens, which protect bone against resorption, than on their own.
A placebo-controlled trial has shown that 15 microgram of ethinyl oestradiol is as effective as 25 microgram daily in reducing both menopausal symptoms and the urinary excretion of calcium and hydroxyproline. Norethisterone 5 mg daily also showed a significant reduction in the climacteric symptoms but was less effective than either of the ethinyl oestradiol doses.
1. Plasma alkaline phosphatase activity and urine hydroxyproline excretion were measured in age-matched premenopausal and postmenopausal women. 2. Both measurements were found to be significantly higher in postmenopausal women. 3. It is proposed that the rise in the plasma alkaline phosphatase, like that in the hydroxyproline excretion, may reflect the onset of bone loss that occurs after the menopause.
1. We have examined the relation between the rate of cortical bone loss and other measured variables in 108 women, untreated and on various therapies, observed for nearly 300 patient years. The majority of the subjects were postmenopausal women with various degrees of simple osteoporosis, but a few cases of hyperparathyroidism and other calcium disorders were included. 2. Calcium balance, bone resorption rats, urinary hydroxyproline and plasma alkaline phosphatase were shown to be related to the rate of bone loss; patients with the more negative balance or the higher values of the other variables had significantly higher rates of loss. The rate of bone loss was independent of the rate of bone formation.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Plasma androstenedione concentration was measured in 92 oophorectomized women in the age range 33 to 76 years. Although this concentration was significantly inversely correlated with age, the data suggest a discrete change in the first half of the sixth decade rather than a continuous fall.
Fasting plasma and urinary calcium and urinary hydroxyproline are known to rise at the menopause, reflecting increased bone resorption. Oestradiol valerate and cyclic oestradiol valerate/DL-norgestrel are shown to reduce this evidence of increased bone loss. It is concluded that these preparations will be effective in preventing post-menopausal loss of bone.
Plasma androstenedione and oestrone concentrations were measured in 72 postmenopasual women. The women included some who had undergone oophorectomy, some with osteoporosis, and normal controls; they were matched for years since menopause. Both hormone concentrations were significantly reduced in the women with osteoporosis. The women who had undergone oophorectomy had hormone concentrations intermediate between the normal and osteoporotic values. Oestrogen deficiency secondary to low androstenedione levels is a major risk factor in postmenopausal osteoporosis, and may be caused by failure of ovarian stromal androgen secretion or some abnormality in the pituitary-adrenal axis.
Explore the source record for details and available documents.
Explore the source record for details and available documents.