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Sheila M Williams

Publications and source records attributed to Sheila M Williams.

32 records · Page 2Linked to original sources
PubMed2004

Interpreting incidence trends for treated end-stage renal disease: implications for evaluating disease control in Australia.

BACKGROUND: Five sources of change modify trends in incidence of treated end-stage renal disease (ESRD): (i) demography; (ii) disease control, comprising prevention and treatment of progressive kidney disease; (iii) competing risks, which encompass dying from untreated uraemia or non-renal comorbidity; (iv) lead-time bias; and (v) classification bias. Thus, rising crude incidence of treated ESRD may conceal effective disease control when there has been demographic change, lessening competing risks, or the introduction of bias. METHODS: Age-specific incidences of treated ESRD in Australia were calculated from Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry data by indigenous/non-indigenous status (all causes) and by primary renal disease (non-indigenous only) for two successive decades, 1982-1991 and 1992-2001. RESULTS: We postulate that less competing risks explained much of the increase in treated ESRD in the elderly and Indigenous Australians. The increase in glomerulonephritic ESRD in non-indigenous Australians could be ascribed mainly to immigration from non-European countries. There was no significant change in incidence of treated ESRD in Indigenous or non-indigenous persons aged less than 25 years, in non-indigenous persons aged 25-64 years for ESRD caused by hereditary polycystic disease or hypertension, or in type 1 diabetics aged over 55 years. End-stage renal disease from analgesic nephropathy had declined. The increase in treated ESRD caused by type 2 diabetic nephropathy appeared to be multifactorial. Lead-time/length bias and less competing risks may have concealed a small favourable trend in other primary renal diseases. CONCLUSION: Whether recent disease control measures have had an impact on incidence of treated ESRD is not yet certain, but seems more likely than implied by previous reports.

Adult↗
PubMed2004

Effect of high-dose vitamin E on insulin resistance and associated parameters in overweight subjects.

OBJECTIVE: Markers of oxidative stress and plasma alanine transferase (ALT) levels are increased and circulating antioxidant concentrations are reduced in individuals with insulin resistance. Vitamin E improves glycemic control in people with diabetes. We tested the hypothesis that vitamin E would decrease markers of oxidative stress and plasma ALT levels and improve insulin sensitivity in overweight individuals. RESEARCH DESIGN AND METHODS: Eighty overweight individuals (BMI >27 kg/m(2)) were randomly allocated to receive either 800 IU vitamin E per day or a matching placebo for 3 months. The dose of vitamin E was increased to 1,200 IU per day for a further 3 months. RESULTS: Plasma peroxides decreased by 27% at 3 months and by 29% at 6 months in the group that received vitamin E and were positively correlated with plasma vitamin E concentrations at the 6-month time point. At 3 months, fasting plasma glucose and insulin concentrations were significantly reduced and homeostasis model assessment increased. These changes were not apparent at 6 months. Plasma ALT concentrations declined significantly throughout the study period. CONCLUSIONS: In conclusion, these findings indicate that vitamin E improves oxidative stress and hepatocellular function. Although insulin resistance also improves, this effect appears transient.

Adult↗
PubMed2004

Outcomes two, three and four years after comprehensive care under general anaesthesia.

OBJECTIVES: The objective was to review the outcomes for three groups of children after two, three and four years following comprehensive dental treatment under general anaesthesia (GA) for 292 children aged 1.8 to 5.9 years of age. DESIGN: The study was a retrospective review of ongoing dental treatment needs following treatment under GA. METHODS: Information including the individual tooth treatments carried out, ongoing care, fluoride status, socioeconomic status and ethnicity was obtained from dental records from the School of Dentistry and the Otago District Health Board School Dental Service. The accuracy of the records was evaluated by clinically examining 10 percent of the children. RESULTS: Ninety-five percent of the treated children were followed up. Fifty-five percent had new caries recorded. For the treatments provided, amalgam had a mean success of 57.1 percent, composite 73.4 percent, compomer 85.2 percent, stainless steel crowns 92.8 percent and pulpotomies 84.6 percent. The majority of replaced restorations were because of new carious lesions. CONCLUSIONS: This study indicated that most of the restorative procedures and materials used have very successful outcomes in these high-risk children. Ongoing risk of dental caries is high despite current preventive approaches. Other preventive approaches should be investigated.

Anesthesia, General↗
PubMed2003

Adrenalectomy-induced cell death in the dentate gyrus: further characterisation using TUNEL and effects of the Ginkgo biloba extract, EGb 761, and ginkgolide B.

This study investigated the potential neuroprotective effects of the Ginkgo biloba extract, EGb-761, and ginkgolide B, on adrenalectomy (ADX)-induced cell death in the dentate gyrus (DG). Adrenalectomised, sham surgery-treated, and naive controls received either EGb-761 (25, 50, or 100 mg/kg), 0.9% saline vehicle control, ginkgolide B (10 or 25 mg/kg), or a polyethylene glycol vehicle control, i.p, daily for 6 days postsurgery. Cell death in the DG was determined by in situ labelling of DNA fragments, using the TUNEL method; sections were counterstained with hematoxylin. Radioimmunoassay was used to confirm a decrease in plasma corticosterone (CORT) after ADX. TUNEL-positive granule cells were observed in the DG at 1 week, but not at 24 h, post-ADX. The rate of granule cell death at this time was highest in the suprapyramidal blade and increased in a crest tip and a rostrotemporal gradient. Whereas CORT replacement completely prevented the occurrence of TUNEL-positive granule cells, EGb-761 and ginkgolide B did not, at any of the doses used. These results suggest that these drugs may not have substantial neuroprotective effects in the ADX model of neurodegeneration.

Adrenalectomy↗
PubMed2003

A new approach to design and implement a lifestyle intervention programme to prevent type 2 diabetes in New Zealand Maori.

Lifestyle programmes provide the greatest opportunity to stem the developing epidemic of type 2 diabetes. This is especially relevant to indigenous people worldwide, and to Maori in New Zealand. The shift from traditional diets and activities to a westernised energy dense diet and a sedentary lifestyle has precipitated the rapid increase in Maori developing type 2 diabetes in New Zealand. Attendance of Maori to mainstream health clinics or programmes has been poor, and a unique approach developed specifically for Maori is required if Maori are going to attend and benefit from lifestyle programmes. We describe the process involved in developing a successful community programme for Maori and outline the novel aspects of the programme which contribute to its acceptability and success in the local community.

Attitude to Health↗
PubMed2003

Implementation of a successful lifestyle intervention programme for New Zealand Maori to reduce the risk of type 2 diabetes and cardiovascular disease.

Lifestyle programmes have been shown to reduce the risk of type 2 diabetes in European populations. The participation of Maori in many mainstream health programmes is poor. This study evaluates a lifestyle intervention programme which is acceptable to Maori and which has objective outcome measures to determine the effectiveness of the programme. Thirty six Maori men and women were recruited for a 4 month programme involving modification of diet and exercise. Insulin sensitivity was measured using a euglycaemic insulin clamp, body composition using dual-energy-absorptiometry and fitness using a submaximal exercise test. Secondary outcome measures included anthropometry, blood pressure, fasting glucose and insulin levels, and lipid profiles. There was a 24% improvement in insulin sensitivity (from 5.1 to 6.3 G/mIU/L, P=0.03, N=29). This was associated with a reduction of 3.1 kg in weight (95%CI -4 to -2) and a reduction of 7 mmHg in systolic blood pressure (95%CI -13, -1). This approach successfully reduced risk for type 2 diabetes and cardiovascular disease in New Zealand Maori in the short term.

Adult↗
PubMed2002

Release of cholesterol from cell membranes to postprandial plasma from mildly hypercholesterolemic subjects: the effect of meals rich in olive and safflower oils.

Triglyceride-rich lipoproteins increase net transport of cell cholesterol to postprandial plasma from healthy subjects after a meal rich in fat and cholesterol. The aim of the present study was to determine the effect of meals rich in polyunsaturated fats (PUFA) and monounsaturated fats (MUFA) and low in cholesterol on net in vitro transport of cholesterol from red blood cells (RBCs) to postprandial plasma from 21 men with mild to moderate hypercholesterolemia in a randomized, crossover trial. Cholesterol concentration increased by 12% due to accumulation of cell cholesterol in fasted hypercholesterolemic plasma incubated with a 2/1 (vol/vol) excess of RBCs at 37 degrees C for 18 hours. The increase in cell cholesterol in plasma was mainly localized in the low-density lipoprotein (LDL) fraction (64%) and the remainder was approximately equally divided between the very-low-density lipoprotein (VLDL) and high-density lipoprotein (HDL) fractions. Accumulation of cell cholesterol in the LDL fraction prevented the significant decrease in LDL cholesterol in plasma incubated alone. When RBCs were incubated with postprandial plasma isolated 4 hours and 6 hours after liquid meals rich in safflower and olive oils, the accumulation of cell cholesterol in plasma increased significantly (11%, P <.004) above values for fasted plasma and irrespective of the type of fat in the meal. Also, the content of cell cholesterol increased significantly (70%, P <.001) in triglyceride (TG)-rich lipoproteins and decreased significantly (P =.006) in the LDL fraction, which remained the main ultimate destination of cell cholesterol in postprandial plasma. The increased loss of cell cholesterol to fasted and postprandial plasma was closely correlated (r > 0.823, P <.001) with the concomitant increase in plasma cholesteryl esters (CE) generated by lecithin cholesterol acyltransferase (LCAT) activity. There was a small (5%), significant (P <.001) increase in plasma cholesterol esterification in postprandial plasma. These data suggest that high-fat meals rich in MUFA and PUFA and low in cholesterol may produce a small postprandial increase in the capacity of plasma to accept cell membrane cholesterol that is limited by a concomitant small increase in plasma cholesterol esterification, in hypercholesterolemic subjects. Thus, low-fat, lipid-lowering diets may have a minimal effect on this capacity but will reduce levels of atherogenic LDL cholesterol that appear to be maintained by diffusion of cell cholesterol to plasma.

Adult↗
PubMed2002

Children who avoid drinking cow milk have low dietary calcium intakes and poor bone health.

BACKGROUND: Information concerning the adequacy of bone mineralization in children who customarily avoid drinking cow milk is sparse. OBJECTIVE: The objective was to evaluate dietary calcium intakes, anthropometric measures, and bone health in prepubertal children with a history of long-term milk avoidance. DESIGN: We recruited 50 milk avoiders (30 girls, 20 boys) aged 3-10 y by advertisement. We measured current dietary calcium intakes with a food-frequency questionnaire and body composition and bone mineral density with dual-energy X-ray absorptiometry and compared the results with those of 200 milk-drinking control children. RESULTS: The reasons for milk avoidance were intolerance (40%), bad taste (42%), and lifestyle choice (18%). Dietary calcium intakes were low (443 +/- 230 mg Ca/d), and few children consumed substitute calcium-rich drinks or mineral supplements. Although 9 children (18%) were obese, the milk avoiders were shorter (P < 0.01), had smaller skeletons (P < 0.01), had a lower total-body bone mineral content (P < 0.01), and had lower z scores (P < 0.05) for areal bone mineral density at the femoral neck, hip trochanter, lumbar spine, ultradistal radius, and 33% radius than did control children of the same age and sex from the same community. The z scores for volumetric (size-adjusted) bone mineral density (g/cm(3)) were -0.72 +/- 1.17 for the lumbar spine and -0.72 +/- 1.35 for the 33% radius (P < 0.001). Twelve children (24%) had previously broken bones. CONCLUSIONS: In growing children, long-term avoidance of cow milk is associated with small stature and poor bone health. This is a major concern that warrants further study.

Adipose Tissue↗
PubMed2002

Dietary counseling to increase natural folate intake: a randomized, placebo-controlled trial in free-living subjects to assess effects on serum folate and plasma total homocysteine.

BACKGROUND: The association between vascular disease and elevated plasma total homocysteine (tHcy) concentrations is caused, in part, by inadequate intakes of dietary folate. Increasing folate intake either through supplements or foods naturally rich in folates has been shown to decrease tHcy concentrations. OBJECTIVE: The aim of this study was to determine whether a similar reduction in tHcy was possible in free-living persons receiving dietary counseling. DESIGN: The study included a 4-wk placebo-controlled dietary intervention trial in which participants consumed either unfortified breakfast cereal (control group) or an extra 350 micro g folate derived from food/d (dietary group). Serum folate and tHcy concentrations in both groups were measured before and after the intervention period, and the concentrations in the dietary group were also measured 17 wk after the intervention period. RESULTS: During the 4-wk intervention, mean dietary folate intake in the dietary group increased from 263 (95% CI: 225, 307) to 618 micro g/d (535, 714), resulting in a mean increase in serum folate of 37% (15%, 63%) and a decrease in tHcy from 12.0 (10.9, 13.3) to 11.3 micro mol/L (10.2, 12.5). A further decrease in tHcy occurred in the dietary group during follow-up, with a final tHcy concentration of 9.7 micro mol/L (8.8, 10.8). CONCLUSIONS: Increasing natural folate intake improved folate status and decreased tHcy concentrations to an extent that may significantly reduce the risk of vascular disease. Dietary modification may have advantages over folic acid fortification because the altered food-consumption patterns lead to increased intakes of several vitamins and minerals and decreased intakes of saturated fatty acids.

Aged↗
PubMed2002

Body fat percentages measured by dual-energy X-ray absorptiometry corresponding to recently recommended body mass index cutoffs for overweight and obesity in children and adolescents aged 3-18 y.

BACKGROUND: Body mass index (BMI; in kg/m2) cutoffs for use with children and adolescents aged 2-18 y that correspond to the well-accepted BMI cutoffs for overweight (> or = 25 but < 30) and obesity (> or = 30) in adults were published recently. OBJECTIVE: The objective was to estimate the percentage body fat (%BF) values typically associated with these BMI cutoffs in children and adolescents. DESIGN: The %BF was measured by dual-energy X-ray absorptiometry in 661 subjects (49% male) aged 3-18 y. Regression equations using BMI, age, and sex were developed to predict the %BF associated with BMI cutoffs for overweight (age-specific BMI equivalent to a BMI of 25 in an 18-y-old) and obesity (age-specific BMI equivalent to a BMI of 30 in an 18-y-old) over this age range. RESULTS: Measurements classified 17.1% of males and 19.8% of females as overweight and 5.5% of males and 7.5% of females as obese. The %BF associated with an obese BMI tended to be higher in peripubertal males (34-36%) than in younger (24-30%) or older (27-30%) males. Although the predicted %BF of young females was similar to that of young males, values rose steadily with age, such that an 18-y-old female with a BMI of 30 had an estimated %BF of 42%, whereas that in males of similar age was 27%. CONCLUSION: The %BF values associated with BMI classifications of overweight and obesity vary considerably with age in growing children, particularly in girls.

Absorptiometry, Photon↗
PubMed2002

Four-year gain in bone mineral in girls with and without past forearm fractures: a DXA study. Dual energy X-ray absorptiometry.

We have previously shown that girls with a recent distal forearm fracture have weaker skeletons than girls who have never fractured. This could be a transient or persistent phenomenon. The present study was undertaken to determine whether the bone mineral content (BMC) of girls with previous distal forearm fractures remains lower 4 years postfracture or if catch-up gain has occurred. We report baseline and follow-up dual energy X-ray absorptiometry (DXA) results for 163 girls: 81 girls from the original control group who remained free of fracture (group 1) and 82 girls from the original group with distal forearm fractures (group 2). In data adjusted for bone area, height, weight, and pubertal status, group 2 girls had 3.5-8.5% less BMC at the total body, lumbar spine, ultradistal radius, and hip trochanter than group 1 at baseline, and 2.4-5.7% less BMC at these sites at follow-up. Even girls from group 2 who did not experience another fracture after baseline (n = 58) did not display greater BMC at follow-up compared with baseline values at any site, indicating that the decreased BMC at the time of fracture had persisted. In group 2, the relative gain in BMC after adjusting for the initial BMC and current bone area, height, weight, and pubertal stage was less than or similar to, but not greater than that of group 1 (ratio [95% CI]: total body, 0.985 [0.972-0.998]; lumbar spine, 0.961 [0.935-0.987]; ultradistal radius, 0.968 [0.939-0.998]; hip trochanter, 0.955 [0.923-0.988]; femoral neck, 0.981 [0.956-1.007]; and 33% radius 0.999 [0.977-1.021]). These findings indicate that girls with distal forearm fractures do not improve their gain of BMC. We conclude that girls who have sustained a distal forearm fracture maintain their lower BMC at most sites for at least 4 years.

Absorptiometry, Photon↗
PubMed2002

Intensive lifestyle changes are necessary to improve insulin sensitivity: a randomized controlled trial.

OBJECTIVE: The extent to which lifestyle must be altered to improve insulin sensitivity has not been established. This study compares the effect on insulin sensitivity of current dietary and exercise recommendations with a more intensive intervention in normoglycemic insulin-resistant individuals. RESEARCH DESIGN AND METHODS: Seventy-nine normoglycemic insulin-resistant (determined by the euglycemic insulin clamp) men and women were randomized to either a control group or one of two combined dietary and exercise programs. One group (modest level) was based on current recommendations and the other on a more intensive dietary and exercise program. Insulin sensitivity was measured using a euglycemic insulin clamp, body composition was measured using dual-energy X-ray absorptiometry, and anthropometry and aerobic fitness were assessed before and after a 4-month intervention period. Four-day dietary intakes were recorded, and fasting glucose, insulin, and lipids were measured. RESULTS: Only the intensive group showed a significant improvement in insulin sensitivity (23% increase, P=0.006 vs. 9% in the modest group, P=0.23). This was associated with a significant improvement in aerobic fitness (11% increase in the intensive group, P=0.02 vs. 1% in the modest group, P=0.94) and a greater fiber intake, but no difference in reported total or saturated dietary fat. CONCLUSIONS: Current clinical dietary and exercise recommendations, even when vigorously implemented, did not significantly improve insulin sensitivity; however, a more intensive program did. Improved aerobic fitness appeared to be the major difference between the two intervention groups, although weight loss and diet composition may have also played an important role in determining insulin sensitivity.

Absorptiometry, Photon↗