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T Diamond

Publications and source records attributed to T Diamond.

At least 109 records · Page 6Linked to original sources
PubMed1991

A therapeutic dilemma: suppressive doses of thyroxine significantly reduce bone mineral measurements in both premenopausal and postmenopausal women with thyroid carcinoma.

We measured lumbar spine, femoral neck, and forearm bone mineral (BMD) in 24 women (14 premenopausal and 10 postmenopausal) who had been treated with total thyroidectomy and 131 Iodine ablation therapy for nonanaplastic thyroid carcinoma and 24 case controls. At the time of the study, all patients were free of cancer (negative 131 Iodine whole body scan and serum thyroglobulin levels less than 0.3 micrograms/L) and all were receiving doses of T4 sufficiently high to prevent a rise in a serum thyroid-stimulating hormone concentration after an iv bolus of TRH. Femoral neck BMD were significantly reduced in both the premenopausal women (89 +/- 3.8% of case controls, 95% CI, 81 to 98) and postmenopausal women (77 +/- 3.9% of case controls; 95% CI, 68 to 86) receiving T4. Lumbar spine BMD and forearm BMD were unaffected in the premenopausal women, but significantly reduced in the postmenopausal women receiving T4 (lumbar spine BMD = 84 +/- 6.2% of case controls; 95% CI, 70 to 98 and forearm BMD = 89 +/- 5.6% of case controls; 95% CI, 76 to 101). Serum bone Gla-protein, a marker of bone turnover, was significantly increased in both the premenopausal and the postmenopausal women receiving T4 compared to case controls (P less than 0.001 for the difference between patient groups and controls). Whereas the cumulative dose of T4 was highly correlated with the femoral neck BMD in the premenopausal patients (r = 0.528; P less than 0.05); the presence of hypogonadism was the main determinant of the lumbar spine and forearm BMD. This data confirms that premenopausal and postmenopausal women receiving suppressive doses of T4 for thyroid carcinoma have diminished bone mineral measurements and are at risk for osteoporosis.

Adult↗
PubMed1990

Development and reversibility of T lymphocyte dysfunction in experimental obstructive jaundice.

This study evaluates the effect of experimental biliary obstruction by bile duct ligation (BDL) and biliary drainage on cell-mediated immunity in Wistar rats. Immune status has been assessed by a mitogen stimulation test of T lymphocytes with phytohaemagglutinin. Animals were followed for up to 35 days after BDL. Regression analysis showed a significant negative correlation between lymphocyte function and the period of jaundice (correlation coefficient -0.57, P less than 0.001). Following BDL for 21 days, groups of animals had internal biliary drainage for 7, 14 and 28 days, and external drainage for 14 days. Compared with obstructed animals, 14 days internal drainage was required to improve lymphocyte function (P less than 0.05). Animals which had 14 days of external drainage had significantly lower lymphocyte stimulation than internal drainage animals (P less than 0.05). The results demonstrate that obstructive jaundice produces a progressive reduction of T lymphocyte function. This can be reversed by biliary drainage, internal drainage being more effective than external drainage.

Animals↗
PubMed1990

Osteoporosis and skeletal fractures in chronic liver disease.

In order to determine the prevalence and severity of hepatic osteodystrophy by non-invasive means we compared 115 consecutive ambulant patients with histologically proven chronic liver disease to 113 age and sex matched control subjects. Methods used included the assessment of fracture prevalence rates, spinal radiography, and measurements of bone mineral density in the spine and the forearm. Spinal and peripheral fractures were more prevalent in the patients than in the control subjects (p less than 0.03 and p less than 0.01 respectively). The type of the underlying liver disease did not significantly affect the fracture prevalence rates, but alcoholic patients sustained more peripheral fractures than patients with other hepatic disorders (p less than 0.05). The bone mineral densities of the spines and the forearms were significantly reduced in male patients of all age groups and in female patients aged 60 years or more (p less than 0.001 for men and p less than 0.01 for women for both measurements). The prevalence rates of spinal and forearm osteoporosis were twice as high among patients with liver disease than in control subjects regardless of the definitions used. The presence of cirrhosis and hypogonadism were major risk factors for development of both spinal (Beta coef = 0.190 and 0.176; SE = 0.079 and 0.086 respectively) and forearm osteoporosis (Beta coef = 0.20 and 0.29; SE = 0.073 and 0.80 respectively). Spinal bone density was the predominant determinant of spinal fractures (Beta coef = -0.007; SE = 0.001), while hypogonadism (Beta coef = 0.363; SE = 0.075) and cirrhosis (Beta coef = 0.185; SE = 0.068) were the major predictors of peripheral fractures. The concentrations of serum calcium and serum vitamin D metabolites and the use of corticosteroids were apparently without effect on the prevalence of skeletal fractures or bone density.

Adrenal Cortex Hormones↗
PubMed1990

Development and reversal of endotoxemia and endotoxin-related death in obstructive jaundice.

Gut-derived endotoxemia has been implicated in postoperative complications in patients with jaundice. It is thought that absence of bile in the gut predisposes to portal absorption of endotoxin and endotoxemia is reversed by oral bile salt replacement or internal biliary drainage and return of bile to the gut, but not by external drainage. We believe that the importance of gastrointestinal bile flow has been overestimated and biliary obstruction and the integrity of hepatocyte and Kupffer cell function are more important in the development and reversal of endotoxemia. In experiment 1, serum endotoxin concentrations were measured in control rats (n = 10) after choledochovesical fistula (n = 15) and bile duct ligation (n = 15) and after relief of biliary obstruction by internal drainage (choledochoduodenostomy; n = 8) and sterile external drainage (choledochovesical fistula; n = 8), with a quantitative limulus assay. In experiment 2, mortality rates were measured in similar groups 48 hours after administration of oral endotoxin (5 mg/100 gm) and intravenous lead acetate (5 mg/100 gm). Bilirubin levels were elevated in bile duct ligation (192 +/- 13 mumols/L) compared with control animals and those with choledochovesical fistula, internal drainage, and external drainage (10.6 +/- 1.5 mumols/L). In experiment 1, significant portal endotoxemia and systemic endotoxemia occurred in bile duct ligation (portal, 130.4 +/- 12.9 pg/ml; systemic, 91.8 +/- 11.0 pg/ml) but not in choledochovesical fistula (portal, 49.3 +/- 17.1 pg/ml; systemic, 27.2 +/- 11.5 pg/ml). Relief of obstruction by both internal and external drainage reversed endotoxemia. In experiment 2, significant death occurred in bile duct ligation (13 of 15) but not in choledochovesical fistula (3 of 15), and relief of obstruction by both internal and external drainage prevented death. These results confirm that biliary obstruction is a more important factor than is gastrointestinal bile flow in the development and reversal of endotoxemia.

Animals↗
PubMed1990

Smooth muscle tumours of the alimentary tract.

Neoplasms arising from smooth muscle of the gastrointestinal (GI) tract are uncommon, comprising only 1% of gastrointestinal tumours. A total of 51 cases of smooth muscle tumour of the GI tract were analysed; 44 leiomyomas and 7 leiomyosarcomas. Lesions occurred in all areas from the oesophagus to the rectum, the stomach being the commonest site. Thirty-six patients had clinical features referable to the tumour. The tumour was detected during investigation or management of an unrelated disease process in 15 patients. The clinical presentation varied depending on tumour location, but abdominal pain and GI bleeding were the commonest presenting symptoms. The lesion was demonstrated preoperatively, mainly by endoscopy and barium studies, in 27 patients. Surgical excision was the treatment of choice, where possible. There was no recurrence in the leiomyoma group but four patients died in the leiomyosarcoma group. Although rare, smooth muscle tumours should be considered in situations where clinical presentation and investigations are not suggestive of any common GI disorder. The preoperative assessment and diagnosis is difficult because of the variability in clinical features and their inaccessibility to routine GI investigation. It is recommended that, where possible, the lesion, whether symptomatic or discovered incidentally, should be excised completely to achieve a cure and prevent future complications.

Adult↗
PubMed1989

Spinal and peripheral bone mineral densities in acromegaly: the effects of excess growth hormone and hypogonadism.

STUDY OBJECTIVE: To measure spinal and peripheral bone mineral densities in patients with acromegaly. DESIGN: Retrospective study. SETTING: Tertiary care center. SUBJECTS: Twenty-four patients with acromegaly and 24 case controls. Seventeen patients (12 eugonadal and 5 hypogonadal) had "active" disease as indicated by elevated plasma concentrations of growth hormone or somatomedin C or both at the time of the study. Seven patients (all hypogonadal) had inactive disease by these criteria. MEASUREMENTS AND MAIN RESULTS: Bone mineral was measured by single photon absorptiometry of the forearm and dual photon absorptiometry of the spine. The forearm bone mineral content of patients with active disease, regardless of gonadal status, was significantly higher than that of normal subjects (P less than 0.001) or of patients with inactive disease (P less than 0.001). The disease "activity" (17.2 +/- 3.7; CI, 9.5 to 24.9) and the sex of the patient (female, -16.6 +/- 3.4; CI, -23.7 to -9.5) were the only independent predictors of forearm measurements. Vertebral bone densities were lower in acromegalic patients than in normal subjects (P less than 0.001). Vertebral values were correlated with the gonadal status of the patients (hypogonadism, -0.126 +/- 0.056; CI, -0.244 to -0.009) and with serum calcium concentrations (0.592 +/- 0.274; CI, 0.032 to 1.153) but not with acromegalic activity. In 13 patients, forearm bone was measured before and after treatment (mean duration of follow-up, 3.4 years). Patients with persistently elevated, plasma somatomedin C concentrations at the end of the study period showed a mean annual increase of 1.5% in forearm measurements during the period of observation, whereas patients with normal concentrations showed a mean annual decrease of 1.0% (P less than 0.01 for the difference between the groups). The percent change in forearm bone mineral content per year (y) was highly correlated with residual somatomedin C activity (x): y = 2.023x - 2.75; r = 0.665. CONCLUSIONS: Forearm and vertebral bone mineral measurements change in opposite directions in acromegaly. The high forearm values are attributable to the growth-promoting action of growth hormone and somatomedin C, whereas low vertebral values are associated with hypogonadism.

Acromegaly↗
PubMed1989

Osteoporosis in hemochromatosis: iron excess, gonadal deficiency, or other factors?

STUDY OBJECTIVE: To define the prevalence, severity, type and pathogenesis of osteopenia in idiopathic hemochromatosis. DESIGN: Prospective study conducted over 18 months. SETTING: Tertiary care center. SUBJECTS: Twenty-two men with idiopathic hemochromatosis and 20 age-matched controls. There were 5 hypogonadal patients, 9 eugonadal nonvenesected patients, and 8 eugonadal venesected patients. MEASUREMENTS AND MAIN RESULTS: All patients and controls were evaluated by spinal radiography, spinal and forearm bone mineral density estimations, dynamic skeletal histomorphometry, and serum biochemistry. Ten patients (45%; 95% CI, 24% to 68%) had osteoporosis as defined by spinal and forearm bone density measurements. Trabecular bone volumes were significantly reduced in the patients (the difference in means between patients and age-matched controls was 3.9%; CI, 1.3% to 6.7%). No patient had osteomalacia. Hypogonadal men had lower bone mass measurements than eugonadal men (radial bone density: beta coefficient = -20.5; CI, -29.2 to -11.8; trabecular bone volume: beta coefficient = -7.1; CI, -10.8 to -3.3). Osteoid and osteoblastic surfaces and bone formation rates were significantly greater in the eugonadal venesected compared with the eugonadal nonvenesected persons (P less than 0.05 for all measurements). CONCLUSIONS: A significant decrease in bone density is seen in idiopathic hemochromatosis, particularly when hypogonadism is present. Low serum free-testosterone concentrations rather than the calciotrophic hormones determine bone mass in this condition.

Adult↗
PubMed1989

Ethanol reduces bone formation and may cause osteoporosis.

INTRODUCTION: The etiology of ethanol-associated osteopenia is not fully understood. In order to define the role of ethanol in the pathogenesis of hepatic osteodystrophy, we compared two groups of alcoholic patients with histologically established alcoholic liver disease. PATIENTS AND METHODS: Twenty-eight patients currently drinking ethanol ("drinkers") and 12 claiming not to have consumed any ethanol for at least six months ("abstainers") were enrolled in the study. In addition, 35 non-alcoholic control subjects without clinical or biochemical evidence of liver disease were also studied. Bone mineral density and various biochemical and hormonal values were measured in each subject; iliac crest biopsies were taken under local anesthesia in the patients and under general anesthesia in the control subjects. RESULTS: Forearm bone mineral densities, spinal bone mineral densities, and iliac crest cancellous bone areas were significantly lower in the alcoholic patients compared with control subjects (p less than 0.01 for all measurements), but these values did not differ between the drinkers and the abstainers. The drinkers, however, had significantly less osteoblastic activity than the abstainers, as assessed by dynamic bone histomorphometry (p less than 0.001). Serum bone Gla-protein concentrations were higher in the abstainers than in the drinkers (p less than 0.001). No differences were seen relating to histologic parameters of bone resorption, although the alcoholic patients who had lower serum free testosterone concentrations than the control subjects also had higher urinary hydroxyproline excretion rates. CONCLUSION: These data suggest that ethanol may be responsible for osteoblastic dysfunction resulting in diminished bone formation and reduced bone mineralization.

Alcoholism↗
PubMed1989

Serum vitamin D metabolites are not responsible for low turnover osteoporosis in chronic liver disease.

We measured the concentrations of vitamin D-binding protein (DBP), total 25-hydroxyvitamin D, total 1,25-dihydroxyvitamin D [1,25-(OH)2D], and free 1,25-(OH)2D in sera of 107 patients with histologically proven chronic liver disease. Bone density measurements and dynamic skeletal histomorphometry were also performed. Osteoporosis, as defined by arbitrary criteria, was found in 42 patients (39%), while no patient had osteomalacia. Serum concentrations of vitamin D-binding protein, 25-hydroxyvitamin D, total 1,25-(OH)2D, and free 1,25-(OH)2D were reduced in patients with cirrhosis, but not in the noncirrhotic patients. Bone formation rates, which were low in 55 patients (51%), were correlated with liver functions, but not with the concentrations of either vitamin D metabolite. A subgroup of 44 patients with low serum 1,25-(OH)2D concentrations and low bone formation rates failed to show an appropriate increase in serum bone Gla protein after 1,25-(OH)2D3 administration even though serum concentrations of 1,25-(OH)2D rose normally. These data suggest that the bone disease in patients with hepatic disorders is not related to the serum concentrations of vitamin D metabolites or the effect of these metabolites on osteoblast function.

Calcitriol↗
PubMed1988

A prospective randomized trial to compare triple dose mezlocillin with triple dose cefuroxime plus metronidazole as prophylaxis in colorectal surgery.

The results of a prospective randomized clinical trial to compare three dose regimens of mezlocillin with cefuroxime plus metronidazole for prophylaxis in emergency and elective colorectal surgery are reported. Severe wound infection occurred in five patients (10%) receiving mezlocillin and in four patients (7%) receiving cefuroxime and metronidazole. There were two episodes of septicaemia, each in the mezlocillin group. The total number of surgically related infections was less with cefuroxime plus metronidazole (n = 10) compared with mezlocillin (n = 17), but this was not statistically significant (P greater than 0.1).

Adult↗
PubMed1988

Endoscopic management of vesico-ureteric reflux in children with neuropathic bladder secondary to myelomeningocoele.

Vesicoureteric reflux (VUR) is a major cause of morbidity and mortality in children with neuropathic bladders secondary to myelomeningocoele. The majority deteriorate with age and early treatment is necessary to avoid this. Endoscopic subureteric Teflon injection ("STING") allows correction of reflux in small children who would otherwise be difficult to manage. The results of treatment of VUR in 41 ureters in 24 children with neuropathic bladders using "STING" are reported. All ureters had grade III-V VUR. Thirty ureters (73%) showed disappearance of reflux after one injection. Of the remaining 11, VUR disappeared in 7 after a second injection. Apart from failure, the only other major complication was septicaemia in one patient. The mean hospital stay was 1.4 days (1-8 days). At a mean follow-up time of 22 months there was radiological improvement in the upper renal tracts in 27 of the 37 (73%) in which VUR disappeared, none has deteriorated and there has been only one relapse. These results suggest that "STING" should be considered as the method of choice in the management VUR in children with neuropathic bladder in view of the problems associated with open operation in these children.

Child↗
PubMed1988

Subdural haematoma associated with long term oral anticoagulation.

Twenty-two patients with subdural haematomas associated with long term oral anticoagulation have been reviewed. Clinical presentation was similar to other subdural haematomas, but patients were generally older and the clinical course was more rapid. The incidence of over-anticoagulation was 23% and there was no correlation between anticoagulant status and the extent of bleeding or prognosis. Mortality was 27%, a residual neurological deficit was present in 14% and 59% made a complete recovery. The results suggest that morbidity and mortality could be reduced by early diagnosis and treatment and any patient on oral anticoagulant therapy who develops a headache or confusion should have urgent neurological investigation, including a CT scan. The indications for long term anticoagulation, particularly in the elderly, should be critically reassessed.

Administration, Oral↗