Pregnancy and development of diabetes in First Nations and non-First Nations women in Alberta, Canada.

AIM: To conduct a retrospective population-based study to examine the risk of developing diabetes after delivery in First Nations and non-First Nations women in Alberta. METHODS: Delivery records (1999-2014) were linked to provincial administrative data, which allowed for a maximum follow-up of 16 years after delivery. Prevalence of pregnancy risk factors were compared by First Nations status. Hazard ratios for diabetes after delivery by First Nations status, high pre-pregnancy body weight (≥91 kg) and gestational diabetes status were estimated using the Cox proportional hazards model. RESULTS: Age-adjusted prevalence of gestational diabetes (7.9% vs 4.6%; P<0.0001), high pre-pregnancy body weight (18.8% vs 10.2%; P<0.0001) and diabetes after delivery (3.9% vs 1.1%; P<0.0001) were higher in First Nations women than in non-First Nations women. Development of diabetes after delivery was higher with First Nations status (hazard ratio 3.0, 95% CI 2.6-3.4), high pre-pregnancy body weight (hazard ratio 3.6, 95% CI 3.3-4.0) and gestational diabetes status (hazard ratio 19.2, 95% CI 17.9-20.6). The highest risk was within First Nations women with high pre-pregnancy body weight and gestational diabetes (hazard ratio 54.8, 95% CI 45.2-66.5) compared to women without these three risk factors. Reduced prenatal visits per pregnancy (8.4 vs 10.7; P<0.0001) and delayed first prenatal visit (time to delivery 23.7 vs 26.7 weeks; P<0.0001) were observed in First Nations women compared to non-First Nations women. CONCLUSION: First Nations women are at greater risk of developing diabetes after pregnancy, with gestational diabetes being the strongest predictor. Strategies that target the specific needs of First Nations women before, during and after pregnancy are required.

Breeding biology and the evolution of dynamic sexual dichromatism in frogs.

Dynamic sexual dichromatism is a temporary colour change between the sexes and has evolved independently in a wide range of anurans, many of which are explosive breeders wherein males physically compete for access to females. Behavioural studies in a few species indicate that dynamic dichromatism functions as a visual signal in large breeding aggregations; however, the prevalence of this trait and the social and environmental factors underlying its expression are poorly understood. We compiled a database of 178 anurans with dynamic dichromatism that include representatives from 15 families and subfamilies. Dynamic dichromatism is common in two of the three subfamilies of hylid treefrogs. Phylogenetic comparative analyses of 355 hylid species (of which 95 display dynamic dichromatism) reveal high transition rates between dynamic dichromatism, ontogenetic (permanent) dichromatism and monochromatism reflecting the high evolutionary lability of this trait. Correlated evolution in hylids between dynamic dichromatism and forming large breeding aggregations indicates that the evolution of large breeding aggregations precedes the evolution of dynamic dichromatism. Multivariate phylogenetic logistic regression recovers the interaction between biogeographic distribution and forming breeding aggregations as a significant predictor of dynamic dichromatism in hylids. Accounting for macroecological differences between temperate and tropical regions, such as seasonality and the availability of breeding sites, may improve our understanding of ecological contexts in which dynamic dichromatism is likely to arise in tropical lineages and why it is retained in some temperate species and lost in others.

Influence of prenatal nutrition and obesity on tissue specific fat mass and obesity-associated (FTO) gene expression.

The recent discovery of an association between body composition, energy intake and the fat mass and obesity-associated (FTO) gene represents a promising new therapeutic target in obesity prevention. In a well, pre-established large animal model, we investigated the regulation of FTO gene expression under conditions either leading to obesity or increased risk of obesity related disorders: i) a sedentary 'Western' lifestyle and ii) prenatal exposure to nutrient restriction. Pregnant sheep were either fed to fully meet their nutritional requirements throughout gestation or 50% of this amount from early-to-mid gestation. Following weaning, offspring were either made obese through exposure to a sedentary obesogenic environment or remained lean. A significant positive relationship between placental FTO gene expression and fetal weight was found at 110 days gestation. In both the newborn and adult offspring, the hypothalamus was the major site of FTO gene expression. Hypothalamic FTO gene expression was upregulated by obesity and was further increased by prenatal nutrient restriction. Importantly, we found a strong negative relationship between the hypothalamic FTO gene expression and food intake in lean animals only that may imply FTO as a novel controller of energy intake. In contrast, FTO gene expression in the heart was downregulated in obese offspring born to nutrient restricted mothers. In addition, FTO gene expression was unaffected by obesity or prenatal diet in insulin-dependent tissues, where it changed with age possibly reflecting adaptations in cellular energetic activity. These findings extend information gained from human epidemiology and provide new insights into the regulation of in vivo energy metabolism to prevent obesity.

Improved cardiovascular health following a progressive walking and dietary intervention for type 2 diabetes.

AIM: To examine the impact of two different lifestyle programmes on cardiovascular health and glycaemic control among people with type 2 diabetes. METHODS: A two-phase 24-week randomized trial. During the first phase, participants were to increase daily steps using a pedometer. At week 12, participants were randomly allocated to either an enhanced lifestyle programme (ELP) targeting walking speed or a basic lifestyle programme (BLP) targeting total daily steps. Both programmes focused on increasing the intake of low glycaemic index foods but utilized different goal setting strategies. Clinical measurements were completed at baseline, week 12 and week 24. Principal outcomes were change in resting pulse rate (PR) and glycated haemoglobin A1c (A1c) between week 12 and week 24 compared between groups using analysis of covariance. RESULTS: Forty-one participants [mean +/- s.d. : age = 56.5 +/- 7.2 years, body mass index (BMI) = 32.7 +/- 6.1 kg/m(2)] were randomized. After 12 weeks, we observed an increase in average total daily steps of 1688 (95% confidence interval: 330-3040, [corrected] p = 0.02). Weight, BMI and systolic and diastolic blood pressure improved (p < 0.01 for all). No changes were observed for energy intake. At week 24, those in the ELP had a lower resting PR (71 +/- 12 b.p.m.) compared with those in the BLP (78 +/- 12 b.p.m.) (adjusted p = 0.03), while no group differences for total daily steps or glycaemic control were observed. CONCLUSIONS: Improvements in cardiovascular health can be expected following a pedometer-based lifestyle modification programme that progresses from walking more to walking faster.

Maternal nutrient restriction between early and midgestation and its impact upon appetite regulation after juvenile obesity.

The impact of maternal nutrient restriction during early-to-midgestation, a period coinciding with early fetal brain development, on appetite regulation and energy balance in the offspring after juvenile obesity was examined. Pregnant sheep were either fed to meet fully their nutritional requirements throughout gestation or 50% of this amount between 30 and 80 d gestation. After weaning, offspring were either made obese through exposure to a sedentary obesogenic environment or remained lean. Maternal nutrient restriction had no effect on birth weight or subsequent growth. At 1 wk of age, only, gene expression for neuropeptide Y in the hypothalamus was reduced in nutrient-restricted offspring. By 1 yr of age, all O animals had increased plasma leptin, nonesterified fatty acids, and insulin, with the latter effect amplified in NR offspring. Fasting plasma glucose, triglycerides, and cortisol were unaffected by obesity. The entrained reduction in physical activity that led to obesity persisted when all animals were maintained within individual pens. However, NRO offspring exhibited reduced daily food intake and were, therefore, no longer in positive "energy balance." This adaptation was accompanied by elevated hypothalamic gene expression for the melanocortin-4 and insulin receptors, AMP-activated kinase, and acetyl coenzyme A carboxylase alpha. In conclusion, nutrient restriction specifically targeted over the period of early fetal brain development contributes to a profoundly different adaptation in energy balance after juvenile obesity. The extent to which this adaptive response may benefit the offspring or result in an exacerbated risk of type 2 diabetes remains to be established.

Acute effect of metformin on exercise capacity in active males.

AIM: Physical activity and metformin are often used concomitantly in the treatment of diabetes, even though little is known about possible interactions between these treatment modalities. This study was designed to examine the acute effect of metformin on oxygen consumption and lactate concentration during exercise. METHODS: Eleven healthy, active men [mean +/- s.d.: age = 29.9 +/- 3.7 years; body mass index = 25.2 +/- 2.8 kg/m2; maximal oxygen consumption (VO2max) = 53.5 +/- 8.9 ml/kg/min] completed a randomized, double-blind, placebo-controlled, crossover study. The testing protocol consisted of a standardized breakfast with metformin (1000 mg) or placebo. Three hours after breakfast, participants underwent a graded maximal exercise test on a cycle ergometer. Approximately 30 min after this exercise test, participants cycled continuously at an intensity below their ventilatory threshold for 45 min (mean exercise intensity = 69 +/- 5.5% of VO2max). RESULTS: During the graded exercise test, average oxygen consumption was higher for the metformin condition (2.9 vs. 2.8 l/min, p = 0.04); however, there was no treatment effect on VO2max or ventilatory threshold. During continuous exercise, lactate was lower for the metformin condition (4.7 vs. 5.4 mmol/l, p = 0.05). Following a standardized lunch, glucose concentrations were lower in the metformin compared with the placebo condition (5.8 vs. 6.4 mmol/l, p = 0.04). CONCLUSION: A single dose of metformin does not acutely influence maximal oxygen consumption or ventilatory threshold in healthy active males. The lower lactate concentration observed during continuous exercise with metformin was an unexpected finding considering that, in the resting state, metformin has been previously associated with a modest increase in lactate concentrations.

Fetal mechanisms that lead to later hypertension.

Extensive epidemiological and experimental evidence suggests the nutritional environment in which a developing conceptus is exposed is a major factor determining later cardiovascular disease. In this review a consideration of the extent to which altered maternal/fetal nutritional environments may predispose toward later anomalies in blood pressure control and hypertension will be undertaken. In particular, a focus will be on potentially novel mechanistic pathways through which early-mid gestational undernutrition may impact upon fetal/adult adipocyte, renal and brain function, that act to increase the risk of later hypertension developing. Within the review we shall also present an opinion on the differing animal models that are currently employed to address developmental programming and introduce a conceptual framework that synthesises current available evidence.

Promotion of physical activity by Canadian Registered Dietitians in daily practice.

BACKGROUND: Dietitians are in an opportunistic position to promote healthy eating and active living. The purpose of this study was to determine counselling strategies of dietitians 1 year after attending a workshop designed to strengthen dietitians' self-efficacy for promoting physical activity (PA) as an adjunct to regular nutrition practice. METHODS: A convenience sample of Registered Dietitians (RDs) in Alberta, Canada (n=103) responded to an invitation via an electronic newsletter to complete a web-based survey that asked about counselling practices related to PA. RESULTS: Thirty-seven workshop attendees (n=37) were compared with a group of dietitians (n=66) who completed the survey but who did not attend the workshop. Nearly all (91%) respondents reported promoting PA in daily practice. Those who attended the workshop were more likely to refer clients to PA professionals (chi2=12.68, P<0.05) than those who were not workshop attendees. CONCLUSIONS: Despite a relatively modest response rate, there were clear suggestions that RDs in Alberta, Canada promote PA in daily practice and attending a workshop designed to facilitate the use of specific tools and strategies for promoting PA in daily practice resulted in increased referral of their clients to exercise specialists.

Controlled outcome evaluation of the First Step Program: a daily physical activity intervention for individuals with type II diabetes.

OBJECTIVE: To conduct a randomised trial of a physical activity (PA) intervention, The First Step Program (FSP) for adults with type II diabetes. DESIGN: A 16-week intervention study and 24-week follow-up assessment. PARTICIPANTS: A total of 47 overweight/obese, sedentary individuals (age=52.7 +/- 5.2 y; BMI=33.3 +/- 5.6 kg/m2) recruited through a diabetes education centre. PRIMARY OUTCOME: daily PA assessed by pedometer (steps/day). SECONDARY OUTCOMES: anthropometric measures (weight, BMI, waist girth, hip girth); indicators of cardiovascular health (resting heart rate and blood pressure); glycemic control (fasting glucose, insulin, HbA1c, glucose concentration 120 min postglucose load); plasma lipid status (total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides). RESULTS: Relative to the CONTROL group, FSP participants increased their PA >3000 steps/day (approximately 30 min/day) during the intervention (P<0.0001). Waist and hip girth decreased (approximately 2-3 cm), but did not differ significantly between groups. Significant changes did not emerge for any of the other variables. CONCLUSIONS: The FSP is a practical intervention that elicits an immediate and profound change in walking behaviour. Such change is an important 'first step' towards increasing the volume and/or intensity of PA necessary to improve long-term health outcomes in this largely sedentary and overweight or obese population. Relapse by 24 weeks indicates that other strategies such as booster sessions are needed to maintain lifestyle change. Further research must determine realistic and responsive health outcomes for this population that are achievable through practical, real-world programming.

Laparoscopic inguinal hernia repair using an anatomically contoured three-dimensional mesh.

BACKGROUND: Laparoscopic inguinal hernia repair frequently is performed with mechanical fixation of a flat polypropylene mesh. Mechanical fixation is associated with pain syndromes, and mesh migration may occur without fixation of flat prostheses. An anatomically contoured mesh (3D Max; Davol, Cranston, RI, USA) using no or minimal fixation would avoid these problems. METHODS: A retrospective case study reviewed 212 transabdominal preperitoneal herniaplasties with 11 x 16-cm 3D Max mesh in 146 patients. Fixation with three helical tacks at the most was used early or with very large defects. RESULTS: Fixation was used in 19% of the cases, but only for 1 of the last 98 patients. As reported, 94% of the patients returned to normal activities by 3 weeks, 97% returned to unrestricted sports by 6 weeks, and 92% complete recovery from surgery by 9 weeks. Fixation or bilateral repair did not alter recovery. Four patients had minor pain or numbness. Symptomatic recurrence was 0%. One asymptomatic indirect recurrence was noted on examination, during a mean follow-up period of 23 months, yielding a 0.55% hernia rate and a 0.42% patient-year recurrence risk. CONCLUSIONS: An anatomically contoured mesh for transabdominal preperitoneal hernia repair often requires no fixation, with minimal risk of neuropathy and less than a 0.5% patient-year recurrence rate. Recovery is excellent even with bilateral repair or some fixation.

Fructose feeding in the suckling-weaning transition in rats: effects on hyperlipidemia in adulthood.

The sucking-weaning transition is characterized by high rates of growth and development and may be a sensitive period during which dietary intake could program metabolism to increase the risk of cardiovascular disease and diabetes in adulthood. Intake of a high fructose (FR) diet is known to induce hypertriglyceridemia and insulin resistance in rats when they are consuming this diet. We examined whether a FR diet fed early in life produces detrimental changes in lipid and glucose metabolism that persist to adulthood. Weanling rats were fed 65% FR (wt/wt), a purified control diet (CNTL) or standard chow (CHOW) for 5 weeks. Beyond 9 weeks of age, all rats were fed CHOW. During FR feeding, plasma triglycerides (TG) were significantly elevated in the FR group (FR = 217 +/- 20; CNTL = 163 +/- 17; chow = 156 +/- 10). At 21 wks of age, TG's were similar in rats fed FR or CNTL versus CHOW at weaning (p > 0.87). Hepatic fatty acid synthase (FAS) activity was elevated in FR and CNTL groups vs. CHOW (65 +/- 7, 72 +/- 6 vs. 48 +/- 4 nmol NADPH/mg protein/min, p < 0.01). There were no differences in indices of glucose homeostasis at 21 weeks of age. Early exposure to a diet high in simple sugars (FR or CNTL) and/or low in fiber during the suckling-weaning transition may contribute to modest dyslipidemia later in life. Together, changes observed in this study may increase the risk of cardiovascular disease in adulthood.

Increased rates of fatty acid uptake and plasmalemmal fatty acid transporters in obese Zucker rats.

Giant vesicles were used to study the rates of uptake of long-chain fatty acids by heart, skeletal muscle, and adipose tissue of obese and lean Zucker rats. With obesity there was an increase in vesicular fatty acid uptake of 1.8-fold in heart, muscle and adipose tissue. In some tissues only fatty acid translocase (FAT) mRNA (heart, +37%; adipose, +80%) and fatty acid-binding protein (FABPpm) mRNA (heart, +148%; adipose, +196%) were increased. At the protein level FABPpm expression was not changed in any tissues except muscle (+14%), and FAT/CD36 protein content was altered slightly in adipose tissue (+26%). In marked contrast, the plasma membrane FAT/CD36 protein was increased in heart (+60%), muscle (+80%), and adipose tissue (+50%). The plasma membrane FABPpm was altered only in heart (+50%) and adipose tissues (+70%). Thus, in obesity, alterations in fatty acid transport in metabolically important tissues are not associated with changes in fatty acid transporter mRNAs or altered fatty acid transport protein expression but with their increased abundance at the plasma membrane. We speculate that in obesity fatty acid transporters are relocated from an intracellular pool to the plasma membrane in heart, muscle, and adipose tissues.

Dietary fiber intakes and insulin requirements in pregnant women with type 1 diabetes.

OBJECTIVE: To determine whether higher dietary fiber intake (water soluble and insoluble) is associated with lower insulin requirements and better glycemic control in pregnant women with type 1 diabetes consuming a self-selected diet. DESIGN: A longitudinal, observational study. SUBJECTS: Pregnant women (n=141) with type 1 diabetes participating in an interdisciplinary program examining the effects of glycemic control on pregnancy outcome (Diabetes and Pregnancy Program, University of Cincinnati Medical Center). MEASUREMENTS: We determined total, water soluble and insoluble fiber intakes from 3-day food records kept each trimester during pregnancy. Outcome measures were insulin dose, pre-meal blood glucose, and glycated hemoglobin concentrations. STATISTICAL ANALYSES: Correlation coefficients, multiple regression, mixed-model analysis of variance. RESULTS: Mean intakes (g/day) of total, water soluble fiber, and insoluble fiber were 14.0 (range, 1.8-33.1), 4.8 (range, 0.6-10.5) and 9.0 (range, 1.1-24.0), respectively. In the second and third trimesters of pregnancy, insulin requirements were inversely associated with total, water soluble, and insoluble fiber intakes; the correlation coefficients ranged from -0.22 to -0.17 (P=.02 to .08). Insulin requirements associated with a higher fiber intake (20.5 g/day) were 16% to 18% lower than for a lower fiber intake (8.1 g/day). These relations remained after adjustment for body weight, disease severity and duration, insulin type, and study year in the second (P=.03 to .10) but not in the third trimester. Pre-meal blood glucose and glycated hemoglobin concentrations were not associated with fiber intake. CONCLUSIONS: Among pregnant women with type 1 diabetes, higher fiber intake is associated with lower daily insulin requirements. Dietary fiber intake should be considered when counseling patients about the management of blood glucose concentrations.

Laparoscopic fundoplication for symptomatic but physiologic gastroesophageal reflux.

Esophageal pH monitoring identifies some patients who have physiologic amounts of esophageal acid exposure but have a strong correlation between symptoms of esophageal reflux events. These patients with symptomatic physiologic reflux probably have enhanced sensory perception of reflux events and may be difficult to control with acid-suppressive therapy. Little is known about the role of fundoplication in such patients. Patients with no endoscopic evidence of gastroesophageal reflux disease and a normal 24-hour pH composite score (<22.4 in our laboratory), but a symptom index (SI = number of symptoms with pH <4/total number of symptoms) greater than 50% were offered laparoscopic fundoplication if acid-suppressive therapy was unsatisfactory. This group comprised 18 (4%) of 459 patients undergoing fundoplication at our institution. Heartburn, dysphagia, and reflux symptoms were scored on a scale of 0 to 10 with patients on and off medicine preoperatively, and at a mean of 7.2 months (range 1 to 32 months) postoperatively. The 18 patients with symptomatic physiologic reflux (6 males and 12 females) had heartburn as a major complaint. Preoperative response to proton pump inhibitors for heartburn was 72% and for all symptoms was 60%. The group had a mean pH composite score of 14 (range 4 to 22). The symptom used to calculate the symptom index was heartburn in 12 patients, regurgitation in three, chest pain in two, and cough in one. An average of 18 symptoms (range 2 to 56) were recorded. The mean symptom index was 82% (range 50% to 100%). A Nissen fundoplication was performed in nine patients and a Toupet fundoplication in nine. Surgery was successful (>90%) in alleviating reflux symptoms in 14 patients and partially successful (>75%) in three of the remaining four patients. Gas bloat and dysphagia were seen in one patient each. Fundoplication is effective at relieving reflux symptoms in carefully selected patients with symptomatic physiologic reflux, with minimal side effects.

High-fructose feeding of streptozotocin-diabetic rats is associated with increased cataract formation and increased oxidative stress in the kidney.

We examined the effects of high-fructose (FR) feeding on the development of diabetic complications in the lens and the kidney of streptozotocin (STZ)-diabetic rats. Male Wistar Furth rats were treated with one of two doses of STZ (HIGH STZ, 55 mg/kg body weight; MOD STZ, 35 mg/kg body weight) or vehicle alone (SHAM) and were then assigned to a control (CNTL) or 400 g FR/kg diet for 12 weeks. At the end of the study, body weight, plasma glucose and insulin concentrations differed among STZ groups (HIGH v. MOD v. SHAM, P < 0.001) but did not differ due to diet. Plasma FR concentrations were significantly higher in FR-fed v. CNTL-fed groups (P < 0.0001) and in HIGH-STZ groups v. MOD-STZ and SHAM groups (P < 0.0004 and P < 0.0001 respectively). Focal length variability of the lens, a quantitative measure of cataract formation, was increased in the HIGH STZ, FR group compared with the HIGH STZ, CNTL group (P < 0.01). The concentration of H2O2 in kidney microsomes was significantly higher in HIGH STZ, FR rats v. HIGH STZ, CNTL rats (P < 0.01). Micro-albuminuria was not observed in any of the groups examined, and there was no evidence of extensive histological damage in the kidney from any rats. Under conditions of severe hyperglycaemia, high FR intake promotes the development of cataracts in the lens of the eye, and results in increased concentrations of substances indicative of oxidative stress in the kidney. Although FR has been suggested as a carbohydrate source for diabetics, a high FR diet coupled with hyperglycaemia produces effects that may promote some of the complications associated with diabetes.

Revisiting the role of physical activity and exercise in the treatment of type 2 diabetes.

There is tremendous potential for improving glycemic control, insulin sensitivity, and cardiovascular risk factors through increased physical activity in individuals with Type 2 diabetes. The demonstrated effects of structured endurance exercise on select outcomes compare favorably with those of typical pharmacological treatment modalities. Adherence to these types of program is problematic, however. We know less about the expected effects of lifestyle-based physical activity. Preliminary results require further investigation, given the apparent acceptability of these programs in this population, however. The effects of resistance training on cardiovascular risk factors to date likely limit its application as an adjunctive therapy for individuals with Type 2 diabetes. The question is no longer "can exercise/physical activity benefit the individual with Type 2 diabetes?" The answer is yes. Future research needs to refine questions regarding type, dose, and magnitude of effects of physical activity (and its subcategory exercise) on glycemic control, insulin sensitivity, and on risk factors for cardiovascular disease within the context of program acceptability and feasibility.

Patterns of success and failure with laparoscopic Toupet fundoplication.

BACKGROUND: Advocates of the Toupet partial fundoplication claim that the procedure has a lower rate of the side effects of dysphagia and gas bloat than a complete Nissen fundoplication. However, there is increasing recognition that reflux control is not always as good with the Toupet procedure as with the Nissen. Therefore, we set out to evaluate the factors contributing to success and failure in patients who underwent laparoscopic modified Toupet fundoplication (LTF). METHODS: A total of 143 patients undergoing LTF for documented gastroesophageal reflux disease (GERD) were evaluated prospectively in regard to their outcomes over a 4-year period. All patients had preoperative esophagogastroduodenoscopy (EGD) and manometry; 24-h pH testing was used selectively. Esophageal manometry was requested of all patients 6 weeks postoperatively. Clinical follow-up was by office visit or questionnaire every 6 months after surgery; patients with significant problems were investigated further. Failure was defined as the development of recurrent reflux documented by endoscopy, 24-h pH test, or wrap disruption on barium swallow, or severe dysphagia persisting >3 months and requiring surgical revision. RESULTS: At a mean follow-up of 30 months (range, 3-51), 21 of 143 patients failed LTF; two had dysphagia and 19 had recurrent reflux. Failure was associated with preoperative findings of a defective lower esophageal sphincter (LES) (14/21), complicated esophagitis (13/21), and failure to divide short gastric vessels (12/19) (chi-square p < 0.05). Defective esophageal body peristalsis, present in 14 patients, resulted in failure in six cases. Presence of either complicated esophagitis or a defective LES was associated with a 3-year 50% success rate, whereas presence of mild esophagitis and a normal LES was reflected in a 96% 3-year success rate. CONCLUSION: Laparoscopic Toupet fundoplication should be reserved for milder cases of GERD, as assessed by manometry and endoscopy.

Effect of diabetes and fructose/non-fructose diet on the optical quality (cataracts) of the rat lens.

PURPOSE: This study measures the effect of moderate and severe levels of diabetes on the optical performance of the rat lens, and evaluates the effect of dietary fructose on diabetic lens damage. METHODS: Moderate and severe diabetes were induced in 250 g rats (Harlan Sprague Dawley) with streptozotocin (35 and 55 mg/kg body weight iv). Animals were fed either a control (glucose/cornstarch) or a 40% (wt:wt) fructose and cornstarch diet and then sacrificed after 7 or 12.5 weeks. These two diets were also fed to two groups in which diabetes was not induced and these rats were also sacrificed at 7 or 12.5 weeks. Lenses removed from animals were analyzed in terms of average focal length (mm), focal length variability (spherical aberration, mm) and relative transmission of light (scatter or number of pixels excited by a refracted laser beam) using an automated laser scanning system. RESULTS: Diabetes disrupted rat lens optical function, both at 7 and 12.5 weeks, as indicated by an increase in focal length variability (FLV). This was true for control and fructose diets. For example, after 12.5 weeks on the diets average FLV values of 0.10 +/- 0.00 mm [n = 9], 0.11 +/- 0.01 mm [n = 9],(control and fructose diets, no diabetes) and 0. 48 +/- 0.04 mm [n = 10], 0.95 +/- 0.11 mm [n = 9], (control and fructose diets, severe diabetes), were measured. The difference between control and fructose diets was significant at 12.5 weeks in the severe diabetes group (p

Clinical rating of compliance in chronic hemodialysis patients.

OBJECTIVE: To develop a clinical rating scale of treatment compliance for use in chronic hemodialysis patients and to test its reliability and validity. METHOD: Forty-eight of 65 patients undergoing hemodialysis treatment at the Ottawa General Hospital during June 1994 met criteria for inclusion and completed the study. Patients underwent a 10-15-minute interview, with 1 of 2 independent clinical interviewers, regarding diet, fluid intake, prescribed medication usage, smoking, alcohol or drug use, and hemodialysis treatment attendance. Following each interview, a predesigned 3-point rating scale evaluating compliance in each of 6 domains (yielding an 18-point total score) to the treatment regimen was completed. Compliance ratings on 10 patients assessed independently by both interviewers were used to establish scale reliability. Criterion validity was assessed by correlating compliance scale scores with 3 biological measures (weight gain [kg], K+ [mmol/l], and PO4 [mmol/l]). RESULTS: Reliability between clinical interviewers using the overall compliance scale score (Intraclass correlation coefficient = 0.825) as well as component subscales was high (kappa values, 0.33-1.00). Biological measures of compliance correlated well with each other but poorly with clinical ratings (range 0.01-0.16). Biological measures identified compliance as being poorer than that found with the clinical interview scale. CONCLUSIONS: The Compliance Rating Scale (CRS) was shown to be reliable but was not well-validated against selected biological measures. Discrepancies between these 2 methods of assessing compliance may be due to differing underlying compliance constructs or patient or interviewer biases. The CRS has value as a patient education tool in that it can be used to instruct patients regarding the benefits of adhering to the treatment regimen.