Search PubMed⌕ Search

Biomedical subjects

T Diamond

Publications and source records attributed to T Diamond.

At least 37 records · Page 2Linked to original sources
PubMed2001

Men and osteoporosis.

BACKGROUND: While strict criteria have been developed for defining osteoporosis in women (bone mineral density measurements more than 2.5 standard deviations below the mean for young adult normal women, i.e. t-score value < -2.5), there still remains a controversy regarding the definition in men. Spinal fractures occur in 5% and hip fractures in 6% of men older than 50 years. There are significant differences between men and women with respect to the pathogenesis of osteoporosis, underlying medical conditions and postfracture sequelae. OBJECTIVE: To provide an overview of the pathogenesis, diagnosis and prevention of osteoporosis in men. DISCUSSION: Osteoporosis is increasingly recognised. Data from the Dubbo Osteoporosis Epidemiology Study suggests that 30% of men in Australia aged over 60 years will suffer from an osteoporotic fracture. It is estimated that 30-60% of men presenting with spinal fractures will have another illness contributing to their bone loss. Osteoporotic fractures in men are associated with higher morbidity and mortality than in women. Lifestyle changes together with daily calcium supplementation should be implemented and vitamin D3 should be considered in men with osteopenia.

Bone Density↗
PubMed2001

Guidelines for treatment of osteoporosis in men.

BACKGROUND: Osteoporosis is associated with significant morbidity and mortality in men. Published randomised controlled trials assessing the benefits of therapy in men with osteoporosis are limited, but those available need to be used to develop management guidelines. OBJECTIVE: To present evidence based guidelines for the treatment of osteoporosis in men. DISCUSSION: It is estimated that 30-60% of men presenting with spinal fractures have another illness contributing to their bone disease. Therefore assessment and treatment of coexisting medical conditions is a vital part of management of osteoporosis. While primary prevention of fractures remains crucial, treatment to ensure further fractures do not occur is equally important. Alendronate is the treatment of choice for men with osteoporosis and fractures, with cyclical etidronate an appropriate alternative and testosterone replacement therapy is indicated in hypogonadal men presenting with osteoporosis.

Calcitriol↗
PubMed2001

Corticosteroid induced osteoporosis. Guidelines for treatment.

BACKGROUND: Last year, Australian Family Physician published 'Guidelines for Management of Postmenopausal Osteoporosis', which were developed by Osteoporosis Australia. Recently, significant advances in our understanding of the treatment of corticosteroid osteoporosis have occurred. OBJECTIVE: The following guidelines, also developed by Osteoporosis Australia, and supported by the National Asthma Campaign, are to help general practitioners identify those patients at risk of this problem and to provide information about current treatment strategies. DISCUSSION: Corticosteroids are widely used and effective agents for the control of many inflammatory diseases. Corticosteroid osteoporosis is a common problem associated with the long term high dose use of these medications.

Adrenal Cortex Hormones↗
PubMed2000

Predictors of bone mass in healthy older men in the community.

OBJECTIVES: To determine the predictors of bone mass (in lumbar spine and femoral neck) in healthy older men living in the community. DESIGN: Cross-sectional study. Bone mineral density (BMD) was measured and known predictors of bone mass and bone turnover were assessed. SUBJECTS AND SETTING: 113 independent, healthy men (70 years and over), not taking glucocorticoid therapy and without medical conditions known to affect bone mass and bone turnover, were recruited from recreational and sports clubs in southern Sydney in April/May 1997. MAIN OUTCOME MEASURES: BMD (measured by dual-energy x-ray absorptiometry); known predictors of bone mass (height; weight; body mass index; calcium level; serum 25-hydroxyvitamin D and free testosterone levels); and markers of bone turnover (serum bone Gla protein and procollagen-1 concentrations, and urinary deoxypyridinoline excretion rates). RESULTS: The mean age of the men was 76.6 years (range, 70-92 years). Mean (SE) BMD of the lumbar spine was 1.143 (0.019) g/cm2 and that of the femoral neck was 0.897 (0.013) g/cm2. BMD values indicating osteoporosis were found in the lumbar spine in 13 men (11.5%) and in the femoral neck in 35 men (31%). The best predictor of lumbar spine BMD was weight (R = 0.37; P = 0.001), and weight- and age-predicted femoral-neck BMD (R = 0.49; P < 0.001). The study group was analysed in two groups with BMD higher or lower than median bone mass corrected for age. Men with lower femoral-neck BMD for age had significantly lower weight, lower lean mass and higher bone Gla protein concentrations. In addition, men with lower lumbar spine BMD for age also had significantly lower fat mass. CONCLUSIONS: These data indicate that measures of body composition, such as weight and lean mass, are the main predictors of bone mass in healthy, community-dwelling older men.

Absorptiometry, Photon↗
PubMed2000

The effects of hormone replacement therapy on plasma lipids in type II diabetes.

OBJECTIVES: The effects of hormone replacement therapy on cardiovascular risk factors in postmenopausal women with non-insulin dependent diabetes mellitus (type II diabetes) is uncertain. METHODS: The effects of estrogen replacement therapy (ERT, conjugated equine estrogen0.625mg orally daily), combined estrogen and continuous progestogen therapy (HRT, 0.625 mg of conjugated equine estrogens plus medroxyprogesterone acetate 5 mg daily) or placebo was compared in 20 postmenopausal type II diabetic women and 20 normal postmenopausal women in a double blind, randomised, crossover study. Patients receiving insulin were excluded from the study and all lipid modifying drugs were ceased at least 4 weeks prior to randomisation. Other medication including oral hypoglycaemics was kept constant for the duration of the study. RESULTS: Women with type II diabetes were a similar age (58.7+/-1.3 years) to the non-diabetic women (59.6+/-1.6 years) but they had a significantly greater body mass index, a higher incidence of treated hypertension, higher fasting plasma glucose levels, higher triglycerides and lower HDL cholesterol levels than non-diabetic women. ERT reduced total cholesterol and LDL cholesterol by a similar extent (8.9-12.3%) in normal and type II diabetic women and increased HDL cholesterol to a similar extent in both groups (11.0 and 8.9% respectively). ERT did not significantly alter fasting triglyceride levels in either group. The addition of medroxyprogesterone acetate 5 mg daily abolished the increase in HDL cholesterol associated with ERT in both groups but did not significantly affect any of the other lipid measurements. ERT and HRT did not significantly alter fasting insulin levels nor alter fasting glucose levels in either non-diabetic women or women with type II diabetes. CONCLUSIONS: ERT and HRT have similar effects on lipids in women with type II diabetes and non-diabetic women after 1 month of therapy.

Cholesterol, HDL↗
PubMed2000

Changes in gastrointestinal morphology associated with obstructive jaundice.

Bacterial translocation has been consistently demonstrated in experimental models of obstructive jaundice. An important factor which promotes this phenomenon is physical injury of the intestinal mucosa. Some previous studies have presented suggestive evidence of this, following bile duct ligation. The aims of this study were to analyse objectively intestinal mucosal morphometric characteristics, to examine for evidence of bacterial translocation, and to assess enterocytes for ultrastructural abnormalities. Adult female Wistar rats were assigned to one of three groups: control (n=8), bile duct ligation (BDL; n=11), or sham operation (n=10). One week later, portal blood, mesenteric lymph nodes, liver, and spleen were harvested and cultured aerobically and anaerobically for evidence of bacterial translocation. Segments of jejunum, ileum, caecum, and large bowel were examined histologically, using light microscopy and morphometrically, using an image analysis system. Electron microscopy was performed on regions of the gastrointestinal tract where significant morphometric alterations had been identified. Significant bacterial translocation was identified following BDL (63. 6% BDL vs. 0% sham vs. 0% control, p<0.01, Fisher's exact test). There was a significant reduction in total mucosal thickness (standard error) [650 microm (23) BDL vs. 731 microm (27) sham vs. 744 microm (95) control] and villous height [451 microm (20) BDL vs. 515 microm (18) sham vs. 559 microm (79) control] in jaundiced animals, compared with sham-operated and control animals (p<0.02, Mann-Whitney U-test). Electron microscopy revealed oedematous change associated with mild inflammation, disruption of desmosomes, and the formation of lateral spaces between enterocytes. In addition, enterocytes showed vacuolation of their cytoplasm and mitochondrial swelling. Increased numbers of bacteria appeared to be attached to the mucosa. These data provide evidence of physical disruption of intestinal mucosa in jaundiced animals, most marked in the distal ileum. Significant bacterial translocation occurs following bile duct ligation and this supports the hypothesis of gut barrier dysfunction with obstructive jaundice.

Animals↗
PubMed2000

Social support and the relationship between family and community violence exposure and psychopathology among high risk adolescents.

OBJECTIVE: The objective of this study was to examine the protective effect of social support in the relationship between exposure to violence and psychopathology. Exposure to violence in the family and exposure to violence in the community were examined separately. Exposure to violence was further divided according to whether violence was experienced as a victim or as a witness. Internalizing and externalizing forms of psychopathology, as well as post-traumatic stress symptomatology were examined. METHOD: Participants consisted of 65 high-risk adolescents admitted consecutively to psychiatric inpatient units. Data were collected by means of individual interviews, self-report questionnaires, and hospital charts. RESULTS: Social support emerged as a protective factor with respect to the maladaptive effects of family violence, experienced as either a victim or as a witness. In contrast, social support did not appear to buffer the maladaptive effects of community violence, regardless of whether violence was experienced as a victim or as a witness. In fact, the relationship between community violence and psychopathology was found to be generally nonsignificant regardless of social support status. CONCLUSIONS: These findings suggest that exposure to family violence may affect development differently than exposure to community violence, allowing social support to effectively buffer the effects of family, but not community violence. This finding highlights the importance of examining violence exposure that occurs within the family separately from violence exposure that occurs within the community.

Adolescent↗
PubMed2000

Biliary complications associated with laparoscopic cholecystectomy: analysis of common misconceptions

AIMS: General surgeons often express the view that the majority of biliary complications following laparoscopic cholecystectomy are caused by trainee surgeons; complications occur most often in the presence of difficult anatomy or pathology; biliary injuries occur more proximally in the biliary tree than at open cholecystectomy; most injuries are recognized at the time of surgery; and most complications can be managed non-operatively. The aim of this study was to determine if these views are substantiated in clinical practice. METHODS: Thirty consecutive patients were referred to a specialist hepatobiliary unit over a 7-year period with biliary complications following laparoscopic cholecystectomy. The mode of presentation, management and outcome of these patients were analysed. RESULTS: In 21 cases the initial operator was a consultant. Four of the 30 complications occurred in the presence of an anatomical variation or unusually difficult pathology. Only patients in whom a previous attempt at repair had been made had injuries at or proximal to the bile duct confluence; the only two deaths occurred in this group. Only 41 per cent of injuries were detected at the time of surgery and 89 per cent required further surgical intervention, hepaticojejunostomy being the most common procedure performed (75 per cent). CONCLUSIONS: The majority of bile duct injuries are not caused by trainees, do not occur because of unusual anatomy or pathology, do not occur in the proximal biliary tree, are not recognized at the time of the initial operation and often require major reconstructive procedures for their management.

Journal Article↗
PubMed2000

Nitric oxide regulates alkaline phosphatase activity in rat fracture callus explant cultures.

Nitric oxide (NO) is synthesised by a group of enzymes called nitric oxide synthases (NOS) and oxidizes to its stable end-products nitrite (NO2-) and nitrate (NO3-) We have previously reported in an in vivo rat model that NO is an important regulator for rat bone fracture healing. This study examines the effects of NO on alkaline phosphatase (ALP) activity in a rat fracture callus explant culture system. Explants of rat femoral fracture callus from days 4, 7, 14 and 28 post fracture induced NO2 release and ALP activity in a biphasic temporal manner, with the highest activity on day 7 and the lowest activity on day 14. Inhibition of NOS by co-incubation with an NOS inhibitor, S-(2-aminoethyl) isothiouronium bromide hydrobromide (AETU), inhibited ALP activity by an average of 50% at each time point (P <0.01). Supplementation with NO donor 3-morpholinosydnonomine hydrochloride (SIN-1) at low doses (25 and 0.025 microM) increased ALP activity by 20% (P < 0.01). ALP mRNA and histochemical ALP activity were localised to osteoblast-like and chondrocyte-like cells within fracture callus. The current study provides evidence that NO plays a regulatory role in ALP activity during rat fracture healing.

Alkaline Phosphatase↗
PubMed2000

Effects of hormone replacement therapy on ambulatory blood pressure and vascular responses in normotensive women.

The effects of chronic oestrogen replacement therapy (ERT) (conjugated equine oestrogen 0.625 mg/day) and combined oestrogen and progestogen replacement therapy (HRT) (ERT plus continuous medroxyprogesterone acetate 5 mg/day) on 24-h ambulatory blood pressure recordings, forearm vascular resistance (FVR) and FVR responses to noradrenaline, angiotensin II, acetylcholine and nitroprusside were studied in 17 normotensive postmenopausal women in a 3-month randomized, double-blind, placebo-controlled crossover trial with 1 month of therapy in each treatment arm. During the last few days of each 1-month treatment period, the subjects underwent 24-h ambulatory blood pressure recordings and measurements of FVR responses. ERT and HRT reduced mean 24-h diastolic blood pressure by 4 and 5 mmHg, systolic blood pressure by 6 and 9 mmHg and mean 24-h heart rate by 5 and 3 beats/min, respectively for ERT and HRT (p < 0.05). Basal FVR was reduced by approximately 18% by ERT and HRT, but FVR responses to noradrenaline, angiotensin II, acetylcholine and nitroprusside were unaffected. ERT and HRT therapy for 1 month lowers blood pressure and basal FVR, but does not appear to influence FVR responses to acetylcholine, nitroprusside, noradrenaline and angiotensin II.

Animals↗
PubMed2000

Postmenopausal osteoporosis treatment guidelines.

BACKGROUND: Several years ago, Osteoporosis Australia published Guidelines for the management of osteoporosis. Since then significant advances in our understanding of the treatment of osteoporosis have been published. The importance of this is heightened as early diagnosis is now possible with precise methods of bone density measurement. OBJECTIVE: This article presents updated guidelines developed on behalf of Osteoporosis Australia for the treatment of postmenopausal osteoporosis to help general practitioners identify those women at risk and to review current treatment strategies. DISCUSSION: Osteoporosis and its associated problems are major health concerns in Australia, especially with an ageing population. While important principles of management are still considered to be maximising peak bone mass and prevention of postmenopausal bone loss by oestrogen therapy, new clinical trial data about drugs such as raloxifene and the bisphosphonates have recently become available and the relative role of various agents is gradually becoming clearer.

Accidental Falls↗
PubMed2000

Management of pancreatic pseudocysts.

BACKGROUND: This review analyses the outcome for patients with acute and chronic pancreatic pseudocysts managed in two major referral centres. PATIENTS AND METHODS: From 1987 to 1997, 33 patients were treated with either acute (n = 19) or chronic (n = 14) pseudocysts. Procedures performed included cystgastrostomy (64%), cystduodenostomy (6%), cystjejunostomy (3%), distal pancreatectomy with resection of pseudocyst (12%), laparotomy with external drainage (9%), endoscopic transpapillary stenting (3%) and endoscopic pancreatic duct sphincterotomy with percutaneous drainage of the pseudocyst (3%). RESULTS: All patients had resolution of their pseudocyst and no patient developed recurrence. There were no deaths in this series. There was a 9% incidence of major complications and a 21% incidence of minor complications. Outcome was excellent in 63% and good in 27% of patients. Two patients (6%) had persistent chronic pain and one patient (3%) had evidence of exocrine pancreatic insufficiency with malabsorption. CONCLUSIONS: Surgical internal drainage of pancreatic pseudocysts can be performed safely with low morbidity and mortality provided patients are carefully selected and their medical management is optimized. Although minimally invasive techniques now offer a variety of treatment options, open surgical drainage is still indicated for a significant number of cases.

Acute Disease↗
PubMed2000

Biliary complications associated with laparoscopic cholecystectomy--an analysis of common misconceptions.

BACKGROUND: Several views are expressed by surgeons on biliary complications following laparoscopic cholecystectomy as follow: most are caused by trainees; complications occur in the presence of difficult anatomy/pathology; injuries occur more proximally than at open cholecystectomy; most injuries are recognised immediately and most can be managed non-operatively. The aim of our study was to determine if these views are substantiated in clinical practice. METHODS: The mode of presentation, management and outcome of thirty-two patients referred to a hepatobiliary unit over a seven year period were analysed. RESULTS: In 72% of cases the initial operator was a consultant. Five of the 32 complications (16%) occurred in the presence of difficult anatomy/pathology. Two patients had proximal biliary tree injuries, the only mortalities (two) occurring in this group. Only 41% of injuries were detected immediately; 87% required surgical intervention, hepaticojejunostomy being the most common procedure performed (75%). CONCLUSION: Our study shows that the majority of bile duct injuries are not caused by trainees, do not occur because of unusual anatomy/pathology, do not occur in the proximal biliary tree and are not recognised at the time of operation. Most injuries ultimately require major reconstructive surgery for definitive management.

Biliary Tract Diseases↗
PubMed1999

Management of liver trauma.

BACKGROUND AND METHODS: Management of blunt or penetrating injuries to the liver remains a significant challenge. This review discusses the mechanisms of liver injury, grading system for severity, available diagnostic modalities and current management options. It is based on a Medline literature search and the authors' clinical experience. RESULTS: Unstable patients require immediate laparotomy, but selected patients who are haemo- dynamically stable may be managed without operation. The preferred operative techniques include resectional debridement, hepatotomy with direct suture ligation and perihepatic packing; anatomical resection, hepatic artery ligation and various bypass techniques have a limited, more defined role for selected injuries. Major complications include haemorrhage, sepsis and bile leak. CONCLUSION: Enhanced resuscitation, anaesthesia and intensive care have contributed to a significant reduction in mortality rates from liver trauma. Optimum results are obtained with a specialist team that includes an experienced liver surgeon, anaesthetist, endoscopist and interventional hepatobiliary radiologist with expertise in managing postoperative complications.

Humans↗