Physician weight loss advice and patient weight loss behavior change: a literature review and meta-analysis of survey data.

Primary care providers (PCPs) can empower their patients to make health-promoting behavior changes. Many guidelines recommend that PCPs counsel overweight and obese patients about weight loss, yet few studies examine the impact of provider weight loss counseling on actual changes in patient behavior. We performed a systematic review and meta-analysis of published studies of survey data examining provider weight loss counseling and its association with changes in patient weight loss behavior. We reviewed the published literature using keywords related to weight loss advice. We used meta-analytic techniques to compute and aggregate effect sizes for the meta-analysis. We also tested variables that had the potential to moderate the responses. A total of 32 studies met criteria for the literature review. Of these, 12 were appropriate for the meta-analysis. Most studies demonstrated a positive effect of provider weight loss advice on patient weight loss behavior. In random effects meta-analysis, the overall mean weighted effect size for patient weight loss efforts was odds ratio (OR)=3.85 (95% confidence interval (CI) 2.71, 5.49; P<0.01), indicating a statistically significant impact of weight loss advice. There was no significant difference in the effectiveness of advice in studies using obese patients alone versus mixed samples (obese alone OR=3.44, 95% CI 2.37, 5.00; mixed sample OR=3.98, 95% CI 2.53, 6.26, P=0.63). PCP advice on weight loss appears to have a significant impact on patient attempts to change behaviors related to their weight. Providers should address weight loss with their overweight and obese patients.

A comprehensive review of oral glucosamine use and effects on glucose metabolism in normal and diabetic individuals.

Glucosamine (GlcN) is a widely utilized dietary supplement that is used to promote joint health. Reports that oral GlcN supplementation at usual doses adversely affects glucose metabolism in subjects with impaired glucose tolerance have raised concerns that GlcN should be contraindicated in individuals with diabetes and those at risk for developing it. This review addresses its potential, when used at typical doses, to affect glucose metabolism and insulin sensitivity in healthy individuals and those with diabetes or 'pre-diabetes'. Publicly available scientific information and data on GlcN were systematically compiled using the electronic search tool, Dialog , and reviewed with special emphasis on human studies. In long-term clinical trials, including those containing subjects with type 2 diabetes or 'pre-diabetes', GlcN produced a non-significant lowering of fasting blood glucose concentrations in all groups of subjects treated for periods of up to 3 years. Owing to limitations in study design, conclusions based on studies that report adverse affects of GlcN on insulin sensitivity and glucose tolerance in pre-diabetic subjects are suspect. However, no definitive long-term studies of GlcN use for individuals with pre-diabetes are available. Nevertheless, based on available evidence, we conclude that GlcN has no effect on fasting blood glucose levels, glucose metabolism, or insulin sensitivity at any oral dose level in healthy subjects, individuals with diabetes, or those with impaired glucose tolerance.

Metabolic and ultrastructural changes in the frog ovarian follicle in response to pituitary stimulation.

Frog ovarian fragments were prevented from ovulating in vitro by the addition of actinomycin D up to 3 hr following pituitary stimulation; but addition of Actinomycin D 6 hr after stimulation was far less effective. Puromycin, on the other hand, effectively inhibited ovulation when added as late as 6 hr after pituitary stimulation. Although actinomycin D reduced uptake of uridine-(3)H, and puromycin reduced uptake of leucine-(3)H and lysine-(14) by pituitary-stimulated ovarian tissue minus oocytes (OTMO) in vitro, it was found that pituitary stimulation did not significantly increase uptake of these compounds by OTMO. Radioautographs of ovarian follicles fixed 6 hr after the addition of pituitary extract and uridine-(3)H in vitro revealed increased RNA synthesis in the peritoneal surface epithelium, compared with unstimulated controls, while the ovarian sac epithelium showed no increase. Gross ultrastructural changes occurred in the peritoneal area of ovarian follicles following pituitary stimulation in vivo, including loss of collagen fibrils, and general disorganization of the connective tissue theca. Changes in the rough endoplasmic reticulum of the peritoneal epithelial cells, while frequently encountered, were less pronounced. None of these changes was observed in the ovarian sac area, or in the interfollicular region. The above data are consistent with the hypothesis that pituitary stimulation of the frog ovary results in increased synthesis of RNA and protein by the peritoneal epithelial cells, and that the protein may be collagenase.

Genetics of growth and reproduction in the Turkey. 17. Changes in genetic parameters over forty generations of selection for increased sixteen-week body weight.

A line (F) of turkeys was selected over 40 generations for increased 16-wk BW. The base population for the F line was a randombred control population that was maintained without conscious selection and used to remove yearly environmental variation in the F line. Selection was effective in increasing 16-wk BW in the F line. Selection differentials based on the mean of the selected parents minus the mean of the entire population (intended) and intended selection differentials weighted for number of offspring produced (actual) did not differ consistently, indicating that natural selection was not opposing artificial selection during the reproduction of the F line. The realized heritability of 16-wk BW in the F line, based on the linear regression of the selection response on accumulated actual selection differential, declined with selection. For both sexes combined, the realized heritability was 0.309 +/- 0.022 (SE), 0.268 +/- 0.033, 0.268 +/- 0.026, 0.166 +/- 0.016, and 0.242 +/- 0.004, respectively, for generations 1 to 10, 11 to 20, 21 to 30, 31 to 40, and 1 to 40. Genetic increases in 16-wk BW in the F line over 40 generations of selection were positively associated with BW at other ages (8 and 20 wk of age and at 50% production), shank length and width at 16 wk of age, days from stimulatory lighting to production of the first egg, and egg weight but were negatively associated with egg production, intensity of lay (maximum and average clutch length and rate of lay), and walking ability. Over the 40 generations of selection, genetic increases in BW in the F line were not associated with changes in broodiness or mortality to 8 wk of age. During generations 31 to 40, BW at 8 and 20 wk of age continued to increase in the F line, but there was no significant change in adult BW, and the only significant change in reproduction traits was for average clutch length (-0.030). Because the genetic changes in some correlated traits were not consistent in all generation intervals studied, the genetic correlation between the selected trait (16-wk BW) and the correlated trait apparently changed with selection.

The effect of genetic increases in egg production and age and sex on breast muscle development of turkeys.

Pectoralis major muscle morphology was studied in both sexes of a turkey line (E) selected long-term for increased egg production and its randombred control (RBC1) from 25 d of incubation through 20 wk posthatch. Pectoralis major muscle samples from 10 individuals from each line-sex-age subgroup were obtained in a manner to prevent contraction. The muscle samples were dehydrated, cleared, embedded in paraffin, sectioned, incubated, and rehydrated before staining with hematoxylin and eosin. Representative sections were given a score by 4 individuals based on breast muscle morphology. The scores ranged from 1 (little extracellular matrix and indistinct muscle fibers) to 5 (large extracellular space and distinct muscle fibers). Scores from 2 to 4 were intermediate to these extremes. The pectoralis major muscle morphology scores were highest at 25 d of incubation and declined greatly at 1 wk of age. The scores increased from 1 to 4 wk of age and remained constant through 20 wk of age. Males had higher scores than females. In the current study, there was no significant difference between the E and RBC1 lines. Based on the results of 3 experiments (2 published and the present one) using the E and RBC1 lines, it appears that genetic increases in egg production may be associated with a slight reduction in pectoralis major muscle morphology scores at 16 wk of age.

Investigating the fundamentals of IMRT decomposition using ten simple collimator models.

The fundamentals of IMRT collimation have been studied using ten conceptual collimators. Spanning a range of complexities from the LINAC jaws alone to a full multi-leaf collimator (MLC), these collimators were designed with two abilities in mind: (1) to be able to define arbitrary field shapes, and (2) to be able to irradiate multiple, disconnected regions in a single segment. The collimators were tested by finding decompositions of random and clinical intensity-modulated beams (IMBs), and collimator performance was measured using both the number of segments required to complete the IMB and the monitor-unit efficiency of the treatment. The decompositions were run on 10 x 10 IMBs with integer bixel values randomly between 1 and 10, and clinical IMBs of varying sizes from lung, head and neck, and pelvic patients taken from a Pinnacle treatment-planning system. Results confirmed that although treatment performance improves with increased collimator complexity, it is not solely dependent on the number of segment shapes deliverable by the collimator but instead on how well these shapes lend themselves to IMRT delivery.

Comparative efficiency of the multi-leaf collimator and variable-aperture collimator in intensity-modulated radiotherapy.

The potential of the variable-aperture collimator (VAC) in intensity-modulated radiation therapy (IMRT) has been evaluated by comparing its performance with that of the multi-leaf collimator (MLC). This comparison used a decomposition algorithm to find the series of collimator segments that would treat a given intensity-modulated beam (IMB). Collimator performance was measured using both the number of segments required to complete the IMB and the monitor-unit efficiency of the treatment. The VAC was modelled with aperture sizes from 4 x 4 cm to 20 x 20 cm, and these apertures were allowed to be located anywhere within the IMB. To enable a direct comparison, a similar scanning MLC was modelled at the same range of aperture sizes. Using both collimators, decompositions were run on 10 x 10 and 20 x 20 random IMBs with integer bixel values ranging from 1 to 10. Clinical IMBs from lung, head and neck, and pelvic patients were taken from a Pinnacle treatment-planning system and tested in the same manner. It was found that for all treatment sites, a small, scanning MLC performs as well or better than an equivalent sized VAC in both number of segments and monitor-unit efficiency, and would be an efficient choice for centres looking for a simple collimator for IMRT.

Genetics of growth and reproduction in the turkey. 16. Effect of repeated backcrossing of an egg line to a commercial sire line.

The turkey industry's view of the relative economic importance of growth and egg production has changed rapidly, and genetic changes by selection within lines may not be rapid enough to meet the changing needs. The objective of the present study was to determine the feasibility of rapidly increasing the BW of dam lines by repeated backcrossing of a dam line (E) to a commercial sire line (B). The experimental E line was selected long-term for increased egg production and was used as the model for a turkey dam line. The B line was larger (more than 3-fold) in BW at 8, 16, and 20 wk of age, had wider breasts (approximately 1.8-fold) at 16 wk of age, and had lower egg production for 180 d (about 3-fold) than the E line. Based on additive genetic variation, males in the F1 generation of the B x E cross did not differ from expected in BW at any age, but females of this cross had BW less than expected at 16 and 20 wk of age. In the F1 generation, breast width of the cross did not differ from the expected value, but egg production for 180 d was greater than expected (126.6 vs.102.3 eggs/hen). After 3 generations of backcrossing, the backcrosses exhibited a gain in 20-wk BW of 12.5 and 8.8 kg, respectively, for males and females; a gain of 5.9 and 5.3 cm in breast width at 16 wk of age for males and females, respectively; and a loss of 74.1 eggs per hen over a 180-d production period. Based on the results of the current and a previous study, limited backcrossing of a dam line to a sire line may be an economically feasible method to greatly increase the BW of dam lines without unduly sacrificing egg production. For maximum gains per generation, backcrossing probably should be used for a maximum of 2 or 3 generations.

Exogenous, but not endogenous, cyclic GMP reduces hepatic pyruvate kinase activity.

We investigated the effects of exogenous cyclic GMP and stimulants of endogenous cyclic GMP accumulation on L-form (hepatic) pyruvate kinase (ATP: pyruvate 2-O-phosphotransferase, EC 2.7.1.40) activity in isolated rat hepatocytes. Exogenous cyclic GMP (200 muM) reduced pyruvate kinase activity, but was less potent than exogenous cyclic AMP (50 muM) (Ki congruent to 120 muM vs. 30 muM, respectively), had a slower onset of action (1.0 vs. 0.3 min, respectively) and a less rapid maximal effect (5.0 vs. 1.0 min, respectively). Similar results were noted with dibutyryl cyclic GMP or dibutyryl cyclic AMP. 1.0 muM acetylcholine increased cyclic GMP concentrations in isolated hepatocytes from 233 +/- 16 to 447 +/- 3 pmol/g cell protein (P less than 0.001), but did not alter pyruvate kinase activity. Similar results were noted with carbamylcholine, NaN3 or acetylcholine plus eserine sulfate. The results suggest a differential effect of exogenous vs. endogenous cyclic GMP on L-form pyruvate kinase activity, and question the physiological relevance of observations with exogenous cyclic GMP in this system.

Distribution and Redistribution of Sulfur Supplied as [35S]Sulfate to Roots during Vegetative Growth of Soybean.

Soybean (Glycine max L.) plants were grown in nutrient solution containing 10 [mu]M sulfate and were treated at various times with [35S]sulfate for 48 h. Growth was then continued in unlabeled solution. The sulfur content of each leaf increased rapidly until it was about 40% expanded; small, additional increases occurred until the leaf was about 70% expanded after which the sulfur content decreased by about 50%. Leaves that were about 60 to 70% expanded during the pulse were strongly labeled but then underwent a significant loss of 35S label. Leaves that were in the early stages of expansion imported little 35S label during the pulse but acquired 35S label during the chase period as they expanded (i.e. redistribution). Most of the redistributed 35S label was derived from other leaves. The rates of both sulfur import and sulfur export by a leaf were greatest at about 70% expansion. Leaves that acquired 35S label during early development retained a much higher proportion of their label than leaves that were more developed, suggesting that the sulfur acquired by leaves during early development is preferentially incorporated into a pool that is less mobile than the sulfur acquired in the later stages of leaf growth.

Effect of Sulfur Nutrition on the Redistribution of Sulfur in Vegetative Soybean Plants.

Soybean (Glycine max L.) plants were grown with sulfate at 2 (S2) or 20 [mu]M (S20) and treated with [35S]sulfate between d 36 and 38. Growth was continued with or without 20 [mu]M sulfate (i.e. S2 -> S0, S2 -> S20, etc.). When the leaves of S20 -> S20 plants were 70% expanded, they exported S and 35S label from the soluble fraction, largely as sulfate, to new expanding leaves. However, 35S label in the insoluble fraction was not remobilized. Very little of the 35S label in the soluble fraction of the leaves of S20 -> S0 plants was redistributed; most was incorporated into the insoluble fraction. The low levels of S remobilization from the insoluble fraction were attributed to the high level of N in the nutrient solution (15 mM). Most of the 35S label in S2 plants at d 38 occurred in the soluble fraction of the roots. In S2 -> S0 plants the 35S label was incorporated into the insoluble fraction of the roots, but in S2 -> S20 plants 35S label was rapidly exported to leaves 3 to 6. It was concluded that the soluble fraction of roots contains a small metabolically active pool of S and another larger pool that is in slow equilibrium with the small pool.

Allocation of S in Generative Growth of Soybean.

Soybean plants (Glycine max L. Merr) were grown with 100 [mu]M S and 15 mM N and studied with respect to S allocation during grain development. The grains accounted for 87% of the S taken up after d 42, the balance coming from internal redistribution of S from leaves and pods. Detailed studies of the leaves, pods, and grains associated with leaf axils 6 and 7 showed that sulfate accumulated in the pods as they expanded to 50% of full length, ahead of grain enlargement, but declined to very low levels as grain growth commenced. Conversely, homoglutathione (hGSH), cysteine, and methionine increased. In developing grains, hGSH accounted for 60 to 90% of the soluble-S but sulfate was barely detectable. The data are consistent with a model in which, under S-limiting conditions, the pods act as sinks for sulfate and grain growth initiates the assimilation of sulfate into hGSH in the pods, and then into developing grains, where it is incorporated into grain proteins.

Effect of Nitrogen Nutrition on Remobilization of Protein Sulfur in the Leaves of Vegetative Soybean and Associated Changes in Soluble Sulfur Metabolites.

The hypothesis that protein S is remobilized from mature leaves in response to N stress but not S stress was examined by transferring vegetative soybean (Glycine max L. Merr) plants grown with adequate sulfate and nitrate to nutrient medium with low sulfate (5 [mu]M) and nitrate at either 15, 7.5, 2, or 0.25 mM. Soluble S decreased to very low levels in mature and maturing leaves, especially in low-N plants. At high [N], insoluble S (protein) in mature leaves remained constant, but at low [N], after the soluble S declined, up to 40% of the insoluble S was exported. The losses were complemented by gains, initially in soluble S, but subsequently in insoluble S, in the expanding leaves and the root. In low-N plants, but not in high-N plants, the decrease in insoluble S in mature leaves was complemented by increases in homoglutathione (hGSH), Cys, and Met. At low [N], but not at high [N], the developing leaf, leaf 5, contained high amounts of soluble S, mostly hGSH. The results suggest that, at low [N], protein S is metabolized to hGSH, which serves as the principal transport compound for the export of organic S.

Effect of soy protein-rich diet on renal function in young adults with insulin-dependent diabetes mellitus.

BACKGROUND: Diabetic nephropathy is the most frequent cause of end-stage renal disease in the Western world. Dietary intake, including protein amount and type, seems to affect the progression of renal disease. This pilot study tested the hypothesis that substituting soy protein for animal protein in the diets of diabetics would help correct glomerular hyperfiltration. METHODS: Twelve young adults (aged 29.9 +/- 2.4 years) with type 1 diabetes mellitus (duration of diabetes 15.1 +/- 2.3 years) and hyperfiltration (glomerular filtration rate, GFR > 120 ml/min/1.73 m2) completed a crossover, dietary intervention trial. After a four-week assessment of baseline characteristics and dietary habits, subjects were assigned to either a control or soy diet for eight weeks after which each subject was crossed over to the alternative diet for another eight-week period. RESULTS: Mean GFR was significantly reduced (p < 0.02) after eight weeks on the soy diet (143 +/- 7.4 ml/min/1.73 m2) compared with baseline (159 +/- 7.7 ml/min/ 1.73 m2) and control diets (161 +/- 10.0 ml/min/1.73 m2). Urinary excretion of the soy isoflavones was significantly higher (p < 0.01) at the end of the soy diet (genistein 1,014.6 +/- 274.1 nmol/h, daidzein 2,645.1 +/- 989.6 nmol/h) compared with baseline (genistein 53.7 +/- 31.1 nmol/h, daidzein 151.1 +/- 74.1 nmol/h) and control diets (genistein 41.1 +/- 13.3 nmol/h, daidzein 127.5 +/- 54.0 nmol/h). The soy diet significantly reduced total and LDL cholesterol by 7% and 9%, respectively. CONCLUSIONS: Implementation of a soy-based diet appears to reduce the GFR and total and LDL cholesterol of young adults with type 1 diabetes and glomerular hyperfiltration, thus affecting positively their clinical profile.

Glucosamine effects in humans: a review of effects on glucose metabolism, side effects, safety considerations and efficacy.

Glucosamine is widely used to relieve symptoms from osteoarthritis. Its safety and effects on glucose metabolism are critically evaluated in this review. The LD50 of oral glucosamine in animals is approximately 8000 mg/kg with no adverse effects at 2700 mg/kg for 12 months. Because altered glucose metabolism can be associated with parenteral administration of large doses of glucosamine in animals and with high concentrations in in vitro studies, we critically evaluated the clinical importance of these effects. Oral administration of large doses of glucosamine in animals has no documented effects on glucose metabolism. In vitro studies demonstrating effects of glucosamine on glucose metabolism have used concentrations that are 100-200 times higher than tissue levels expected with oral glucosamine administration in humans. We reviewed clinical trial data for 3063 human subjects. Fasting plasma glucose values decreased slightly for subjects after oral glucosamine for approximately 66 weeks. There were no adverse effects of oral glucosamine administration on blood, urine or fecal parameters. Side effects were significantly less common with glucosamine than placebo or non-steroidal anti-inflammatory drugs (NSAID). In contrast to NSAID, no serious or fatal side effects have been reported for glucosamine. Our critical evaluation indicates that glucosamine is safe under current conditions of use and does not affect glucose metabolism.

Hypocholesterolemic effects of different bulk-forming hydrophilic fibers as adjuncts to dietary therapy in mild to moderate hypercholesterolemia.

Hypercholesterolemia is a significant risk factor for coronary heart disease, and the hypocholesterolemic effects of psyllium are well established. This placebo-controlled, parallel study compared psyllium with methylcellulose, calcium polycarbophil, and placebo as dietary adjuncts in treating mild to moderate hypercholesterolemia. Of 163 men and women recruited with serum cholesterol levels above 5.17 mmol/L (200 mg/dL), 105 completed 8 weeks of an American Heart Association step I diet and then augmented the diet with one of the fiber supplements for 8 additional weeks. Incremental differences from placebo for low-density lipoprotein cholesterol were -8.8% for psyllium, -3.2% for methylcellulose (not significant), and +8.7% for calcium polycarbophil; and for total cholesterol the differences were -4.3% for psyllium (not significant), -1.4% for methylcellulose (not significant), and +5.9% for calcium polycarbophil. Compliance was 94% to 96%, and only mild gastrointestinal side effects were observed. In managing mild to moderate hypercholesterolemia, methylcellulose and calcium polycarbophil provide little or no additional benefit, while psyllium significantly enhances the American Heart Association diet effects.

Cholesterol-lowering effects of psyllium hydrophilic mucilloid for hypercholesterolemic men.

The effect of psyllium hydrophilic mucilloid on serum cholesterol levels was investigated in 26 men with mild to moderate hypercholesterolemia (range of cholesterol level, 4.86 to 8.12 mmol/L [188 to 314 mg/dL]) in a double-blind, placebo-controlled parallel study. Following a two-week baseline period, subjects were treated for eight weeks with 3.4 g of psyllium or cellulose placebo at mealtimes (three doses per day). All subjects maintained their usual diets, which provided less than 300 mg of cholesterol per day and approximately 20% of energy from protein, 40% from carbohydrate, and 40% from fat. Eight weeks of treatment with psyllium reduced serum total cholesterol levels by 14.8%, low-density lipoprotein (LDL) cholesterol by 20.2%, and the ratio of LDL cholesterol to high-density lipoprotein cholesterol by 14.8% relative to baseline values. The reductions in total cholesterol and LDL cholesterol became progressively larger with time, and this trend appeared to be continuing at the eighth week. Psyllium treatment did not affect body weight, blood pressure, or serum levels of high-density lipoprotein cholesterol, triglycerides, glucose, iron, or zinc. No significant changes in serum lipid levels, body weight, blood pressure, or other serum parameters were observed with placebo treatment. Subject adherence to psyllium treatment was excellent, and no adverse effects were observed. Results of this study show that psyllium is an effective and well-tolerated therapy for mild to moderate hypercholesterolemia.

Genetic variation in pure lines and crosses of large-bodied turkey lines. 3. Growth-related measurements on live birds.

An experimental line (F) selected over 34 generations for increased 16-wk BW was reciprocally crossed with a primary breeding sire line (C) from a large international turkey breeder to study the inheritance of growth-related traits measured on live birds. All genetic groups were grown intermingled in confinement with sexes reared in different houses. The traits measured included BW at 8, 16, and 20 wk of age and shank length, shank width, shank depth, breast width, and walking ability scores at 16 wk of age. Walking ability was rated from 1 to 5 with 1 representing birds with no leg defects and no difficulty walking and 5 indicating birds with extreme lateral deviations of the legs and great difficulty walking. Ratings of 2, 3, and 4 represented intermediate values. The F line had a different growth pattern than the C line with the F line being larger than the C line at 8 wk of age, but the reverse was true at 16 and 20 wk of age. The difference in BW between the C and F lines increased from 16 to 20 wk of age. The C line had wider breasts than the F line at 16 wk of age. The F line had longer shanks than the C line. Shank width was larger in the C line than the F line for females but not males. No line difference in shank depth was observed. Walking ability scores at 16 wk of age were lower (better) in the C line than in the F line for males but not females. Significant heterosis in BW of the crosses of the F and C lines was observed at all ages in males (range = 3.3 to 5.6%) and only at 8 wk of age in females (3.6%). These results were similar to an earlier study in which the F line was crossed with a primary-breeding sire line from 2 other international turkey breeders. No significant heterosis in the crosses of the C and F line was observed for breast width and shank measurements. Heterosis was significant for walking ability scores of females (-3.0%) but not males. Reciprocal effects, a measure of sex linkage and maternal influences, were noted only for shank length and the direction of the difference was not the same in the 2 sexes.

Genetic variation in pure lines and crosses of large-bodied turkeys. 4. Body shape and carcass traits.

An experimental line (F) of turkeys selected long-term for increased 16-wk BW was reciprocally crossed with a primary breeding sire line (C) from a major international turkey breeder to study the inheritance of carcass traits and body shape. The birds were weighed and killed at 16 wk of age, and various measurements of muscling, leg bones, and body shape were made. The BW of males were 16.0 and 15.1 kg, respectively, in the C and F lines. The respective BW for females were 12.2 and 11.2 kg. Additive genetic variation, as indicated by differences between the F and C line, was a more important source of variation for measurements of muscling than for measurements of leg bones. The anterior and posterior depth of the body and the ratio of these measurements differed between the F and C lines. Body cavity volume index (length x width x height) differed between lines in females and sexes combined. The weights of some internal organs (gizzard, heart, liver, pancreas, and spleen), but not others (proventriculus and lungs), differed between lines, and the total weight of these organs was greater in the C line than in the F line. However, the ratio of total demand organs (muscles and bones) to the total weight of the supply organs was less in the F line than in the C line. Heterosis was a more important source of variation in body weight and weights of the pectoralis major and pectoralis minor muscle weights in males than in females. Heterosis for some body shape measurements (keel length, body depth 1, body depth 2, body depth ratio, body cavity height, and body cavity volume index) was significant in some comparisons. Heterosis (range = 3.64 to 3.99%) for leg muscle measurements (thigh muscles, drumstick muscles, and total leg muscles) was highly significant (P < or = 0.01) based on the analysis for both sexes. Differences between the reciprocal crosses of the F and C lines were more frequent in the present study than in previous studies in which the F line was reciprocally crossed with sire lines from 2 other commercial breeders. However, when the data from the previous studies and the current study were summarized, it appeared that the only reciprocal effect that was consistent was for the weight of the drumstick muscles, indicating sex linkage or maternal effects may influence the weight of these muscles.

Dietary fiber--an overview.

Diabetes diets should aim at ensuring an ideal body weight with normoglycemia and normolipidemia. The consensus recommendations of various diabetes associations suggest that these goals are most likely to be achieved by diets high in complex carbohydrates and fiber and low in fat. A typical diabetes diet containing 55-60% energy as carbohydrate (at least 66% complex), less than 30% energy as fat, 0.8 g.kg-1 desirable body wt.day-1 protein, and approximately 40 g fiber/day, improves glycemic control, reduces levels of serum atherogenic lipids, decreases blood pressure in those with hypertension, and reduces body weight in the obese. This diet also reduces insulin requirements in the insulin-treated patient and can promote discontinuation of insulin therapy in those with non-insulin-dependent diabetes mellitus. This article presents our experience with high-fiber high-carbohydrate diets and reviews knowledge on the likely mechanisms of action of fiber, its long-term effectiveness, and the concerns about its long-term safety. We suggest that reports on the risk of hypertriglyceridemia from on the risk of hypertriglyceridemia from high-carbohydrate diets are inconsistent and invalidated if those diets are also high in fiber content. Similarly, we urge some caution in prescribing high-monounsaturated fat diets as an alternative to high-carbohydrate diets, at least until the long-term implications of the former are clearer. We believe that there is no compelling reason to change the current diabetes diets, which should continue to be high in carbohydrate and fiber content.