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T Diamond

Publications and source records attributed to T Diamond.

At least 19 recordsLinked to original sources
PubMed1992

Effect of extended cold ischaemia with UW solution on graft function after liver transplantation.

Studies in animals on the use of UW solution in liver transplantation have shown an inverse relation between cold ischaemia time (CIT) and graft function. There are few clinical data on this relation in human beings. We have investigated the effect of extended cold ischaemia in a prospective study. We assessed early graft function and subsequent outcome for 306 consecutive elective liver transplantations; for analyses, grafts were grouped according to CIT (< 12 h group A, > or = 12 h group B), since a preliminary study identified 12 h as a significant cut-off point. Initial graft function was better in group A than group B, as shown by maximum alanine aminotransferase activity (mean 623 [805] vs 946 [1148], p = 0.02), bile production on days 1-3 (p < 0.05), maximum serum bilirubin by day 10 (206 [166] vs 244 [163] mumol/l, p = 0.04), and frequencies of primary non-function (1 [0.4%] vs 4 [7%], p = 0.006) and hepatocyte necrosis on routine biopsy sample after reperfusion (18% vs 31%, p = 0.04). Long-term outcome was also better in group A than group B; graft and patient survival rates were higher and fewer retransplantations were needed. These findings suggest that cold ischaemia in UW solution for longer than 12 h is a risk factor for graft function and patient survival. We recommend that the limit of the safe CIT be reconsidered.

Adenosine↗
PubMed1992

Management strategies in resection for hilar cholangiocarcinoma.

Between 1960 and 1990, resection was performed in 23 of 122 patients who underwent surgical treatment for hilar cholangiocarcinoma. Local excision of the lesion alone was performed in 10 cases (43%). Hepatic resection for tumor extending to the secondary bile ducts or hepatic parenchyma was performed in 13 cases (57%): extended right hepatectomy (3), right hepatectomy (1), extended left hepatectomy (6), left hepatectomy (2), and left lobectectomy (1). In three other cases, resection by total hepatectomy and liver transplantation was performed, but these were not included in the analysis of results for resection. Significant operative complications occurred in only two cases (8.7%), and the operative mortality rate was zero. In four cases, complete excision of the tumor could not be achieved macroscopically (macroscopic curative resection rate 19/122; 15.6%). In nine cases, the margins of the resected specimens were free from tumor on histologic examination (microscopic curative resection rate, 9/122; 7.4%). In 10 cases, the resection margins were found to contain tumor on histologic examination. The overall survival rate was 87% at 1 year, 63% at 2 years, and 25% at 3 years (median survival, 24 months). The survival and freedom from recurrence rates for patients with free resection margins was superior to that for patients with involved resection margins or residual macroscopic disease. A potentially curative resection, with histologically negative margins and no recurrence to date, was achieved in seven patients using the following procedures: local excision for two type I lesions; left hepatectomy plus excision of segment 1 for two type IIIb lesions and one type IV lesion; right hepatectomy and right hepatectomy plus excision of segment 1 for two type IIIa lesions. These results indicate that improved survival in hilar cholangiocarcinoma can be achieved by resection, with minimal morbidity and zero mortality rates, if histologically free resection margins are obtained. To achieve this, we recommend the following procedures for each type of lesion, based on our experience and on anatomic considerations: local excision for type I; local excision plus resection of segment 1 for type II; local excision, resection of segment 1, and right or left hepatectomy for types IIIa and b; hepatectomy plus liver transplantation for type IV.

Adenoma, Bile Duct↗
PubMed1992

Congenital respiratory-esophageal fistula in the adult. Report of nine cases and review of the literature.

Congenital tracheoesophageal or bronchoesophageal fistulas, if not associated with esophageal atresia, may not appear initially until adult life. Nine such cases (two tracheoesophageal and seven bronchoesophageal) are reported. The chief presenting symptoms were recurrent bouts of coughing, after drinking, and hemoptysis. In the majority of cases the duration of symptoms exceeded 15 years. The diagnosis was confirmed in seven patients by esophagography, in one patient by bronchoscopy, and in one patient the fistula was discovered incidentally during thoracotomy. The esophageal opening of the fistula was in the lower third in seven patients and in the middle third in two. Bronchoesophageal fistulas communicated with a segmental bronchus in four patients and with a main or lobar bronchus in three. Treatment involved excision of the fistula (five patients) or division and suturing (four patients). Postoperative follow-up revealed no long-term sequelae except persistent chronic respiratory failure in one patient. The respiratory failure had developed before treatment of the fistula. The analysis of this series and a review of the literature underline the high index of suspicion required in all cases of chronic cough and lung suppuration, to diagnose this benign condition before life-threatening complications occur.

Adult↗
PubMed1992

Partial portacaval shunt: renaissance of an old concept.

BACKGROUND: Partial diversion of the portal system aims to reduce portal pressure sufficiently to prevent variceal hemorrhage but still maintain adequate hepatic portal flow. METHODS: Partial portacaval shunts were performed in 25 patients with cirrhosis with portal hypertension and esophageal varices, either as a primary procedure (n = 16) or for failure of endoscopic sclerotherapy (n = 9), with ringed polytetrafluoroethylene prostheses (8, 10, or 12 mm). RESULTS: All patients have now been followed up for at least 1 year. The operative mortality rate (2 months) was 4%. In 24 patients who survived beyond the initial perioperative period, there was no recurrence of variceal bleeding. Cumulative shunt patency (up to 4 years) is 96%. Acute encephalopathy was detected in two patients (8%), but no patients had signs of chronic encephalopathy. Intraoperative pressure measurements revealed a significant correlation between decreasing diameter of the graft and the percentage reduction of the portacaval pressure gradient. Selective angiography, performed 1 year after surgery, revealed that hepatopetal flow was maintained in 70% of patients with a 10 mm shunt. CONCLUSIONS: It is possible to achieve a partial portacaval shunt, related to the diameter of the prosthesis, that preserves hepatopetal flow in the majority of patients and is associated with a very low incidence of shunt thrombosis. This effectively prevents recurrent variceal bleeding and significant postoperative encephalopathy. The performance of subsequent orthotopic liver transplantation is not compromised. The technique is recommended, either as a primary procedure or when sclerotherapy has failed, in patients with good liver function who are unlikely to require early liver transplantation (grade A and some grade B cirrhosis).

Adolescent↗
PubMed1991

Effects of testosterone and venesection on spinal and peripheral bone mineral in six hypogonadal men with hemochromatosis.

To measure the effect of testosterone replacement and venesection on spinal and peripheral bone mineral we prospectively studied six hypogonadal men and six eugonadal men with idiopathic hemochromatosis for 24 months. Venesections were performed every week on all patients, and intramuscular injections of testosterone were administered every 3 weeks to the hypogonadal men only. Bone mineral was measured by quantitative computed tomography in the spine and by single-photon absorptiometry in the forearm. During the 24 month period of observation serum testosterone concentrations and serum ferritin levels became normal. In the hypogonadal men mean lumbar spine bone mineral increased by 13.1 +/- 4.9% (95% CI, 0.5-25.6) and mean forearm bone mineral increased by 4.7 +/- 3.8% (95% CI, -5.1 to 14.6). In contrast in the eugonadal men treated over the same period, mean lumbar spine bone mineral decreased by 3.5 +/- 2.8% (95% CI, -10.9 to 3.8, P less than 0.01) and mean forearm bone mineral remained virtually unchanged (0.07 +/- 0.9%; 95% CI, -1.7 to 3.1, P less than 0.05). These data suggest that bone mineral increases in the lumbar spine and in the forearm in hypogonadal men with hemochromatosis treated by testosterone replacement and venesection.

Adult↗
PubMed1991

Does iron affect osteoblast function? Studies in vitro and in patients with chronic liver disease.

In order to study the role of trace elements as potential osteoblastic toxins, we measured bone aluminum, copper, and iron in 106 ambulant patients with histologically proven liver disease. We used analytical and histochemical methods and we correlated our results with serum biochemistry, forearm and spinal bone density, and dynamic bone histomorphometry. Patients with chronic liver disease had higher iron-stained perimeters than control subjects (P less than 0.001). However, the mean iron-stained perimeter was no greater than 5% of the total mineralized bone perimeter and did not correlate significantly with either the osteoblast perimeters or bone formation rates. The mean concentration of bone iron were 2.5 times (P less than 0.01) greater in the patients than in the controls although 80% of the patients fell within the normal range. There was a weak negative correlation between bone iron and the osteoblast perimeters (R = 0.18, P = ns) and between bone iron and bone formation (R = -0.30, P less than 0.05). There were 57 patients (56% of the total) with diminished bone formation, but only 16 had elevated bone iron concentrations. In a regression analysis, age, hypogonadism, and serum albumin concentrations were the most important predictors of osteoblast perimeters and bone formation rates. In vitro experiments using rat osteoblast-like osteosarcoma cells showed that an iron concentration of 400 mumol/liter was required to diminish cellular proliferation and function. Iron concentrations are elevated in the bones of patients with chronic liver disease. However, there is at present insufficient evidence that this metal is responsible for the osteoblast dysfunction seen in these patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
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↗