Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Fat Substitutes”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,045 records · Page 58Linked to original sources

Switching effective antiretroviral therapy: a review.

One approach to target the long-term metabolic toxicity and disfiguring body-shape changes associated with antiretroviral therapy is to switch one component of a regimen to an alternative drug, usually from a different class of antiretrovirals. Most commonly, substitutions have involved protease inhibitors, but the thymidine analogue nucleosides, especially stavudine, have been investigated more recently. Certain trends from these studies have emerged. First, if the patient has had sustained viral suppression, switching therapy is generally virologically safe. Second, metabolic disturbances, such as insulin resistance and dyslipidemia, appear to be at least partially reversible. Substitution of other agents for protease inhibitors has not been associated with reversal or improvement in fat redistribution. Studies in which thymidine analogue reverse-transcriptase inhibitors have been switched have reported modest improvements in peripheral lipoatrophy. Larger, controlled, long-term studies and a more standardized approach to definition of metabolic and morphological abnormalities are needed.

Anti-HIV Agents↗

A CT calibration method based on the polybinary tissue model for radiotherapy treatment planning.

A method to establish the relationship between CT number and effective density for therapeutic radiations is proposed. We approximated body tissues to mixtures of muscle, air, fat and bone. Consequently, the relationship can be calibrated only with a CT scan of their substitutes, for which we chose water, air, ethanol and potassium phosphate solution, respectively. With simple and specific corrections for non-equivalencies of the substitutes, a calibration accuracy of 1% will be achieved. We tested the calibration method with some biological materials to verify that the proposed method would offer the accuracy, simplicity and specificity required for a standard in radiotherapy treatment planning, in particular with heavy charged particles.

Adipose Tissue↗

Androgens and the ageing male.

Hypogonadal men share a variety of signs and symptoms such as decreased muscle mass, osteopoenia, increased fat mass, fatigue, decreased libido and cognitive dysfunctions. Controlled trials have demonstrated favourable effects of androgen substitution therapy on these signs and symptoms in men with severe primary or secondary hypogonadism. Thus, androgen substitution therapy is warranted in men with true hypogonadism at all ages. Symptoms experienced by otherwise healthy ageing males are non-specific and vague, although some may be similar to symptoms of hypogonadism. Therefore, the term 'andropause' has been suggested. However, testosterone levels show no or only modest variation with age in men; with large prospective studies suggesting a maximal decline of total testosterone of 1.6% per year. Thus, in contrast to the sudden arrest of gonadal activity in females around menopause, men do not have an andropause. As large placebo-controlled studies of androgen treatment in elderly males are lacking, proper risk assessment of adverse effects such as prostate cancer following testosterone treatment in elderly males is completely lacking. In the future, testosterone therapy may prove beneficial in some elderly males with low-normal testosterone levels. However, at this point in time, widespread use of testosterone in an elderly male population outside controlled clinical trials seems inappropriate.

Aging↗

Adipose tissue compensates for defect of phosphatidylinositol 3'-kinase induced in liver and muscle by dietary fish oil in fed rats.

The present work aimed to study in rats whether substitution of a low level of fish oil (FO; 2.2% of calories) into a low-fat diet (6.6% of calories from fat as peanut-rape oil or control diet) 1) has a tissue-specific effect on insulin signaling pathway and 2) prevents dexamethasone-induced alteration of insulin signaling in liver, muscle, and adipose tissue. Sixteen rats were used for study of insulin signaling, and sixteen rats received an oral glucose load (3 g/kg). Eight rats/group consumed control diet or diet containing FO over 5 wk. Four rats from each group received a daily intraperitoneal injection of saline or dexamethasone (1 mg.kg(-1).day(-1)) for the last 5 days of feeding. In liver, FO decreased phosphatidylinositol 3'-kinase (PI 3'-kinase) activity by 54% compared with control diet. A similar result was obtained in muscle. In both liver and muscle, FO clearly amplified the effect of dexamethasone. FO did not alter early steps of insulin signaling, and in muscle GLUT4 protein content remained unaltered. In adipose tissue, FO increased PI 3'-kinase activity by 74%, whereas dexamethasone decreased it by 65%; inhibition of PI 3'-kinase activity by dexamethasone was similar in rats fed FO or control diet, and GLUT4 protein content was increased by 61% by FO. Glycemic and insulinemic responses to oral glucose were not modified by FO. In conclusion, FO increased PI 3'-kinase activity in adipose tissue while inhibiting it in liver and muscle. The maintenance of whole body glucose homeostasis suggests an important role of adipose tissue for control of glucose homeostasis.

Adipose Tissue↗

Enhancement of arm exercise endurance capacity with dihydroxyacetone and pyruvate.

The effects of dietary supplementation of dihydroxyacetone and pyruvate (DHAP) on endurance capacity and metabolic responses during arm exercise were determined in 10 untrained males (20-26 yr). Subjects performed arm ergometer exercise (60% peak O2 consumption) to exhaustion after consumption of standard diets (55% carbohydrate, 15% protein, 30% fat; 35 kcal/kg) containing either 100 g of Polycose (placebo, P) or DHAP (3:1, treatment) substituted for a portion of carbohydrate. The two diets were administered in a random order, and each was consumed for a 7-day period. Biopsy of the triceps muscle was obtained immediately before and after exercise. Blood samples were drawn through radial artery and axillary vein catheters at rest, after 60 min of exercise, and at exercise termination. Arm endurance was 133 +/- 20 min after P and 160 +/- 22 min after DHAP (P less than 0.01). Triceps glycogen at rest was 88 +/- 8 (P) and 130 +/- 19 mmol/kg (DHAP) (P less than 0.05). Whole arm arteriovenous glucose difference (mmol/l) was greater (P less than 0.05) for DHAP than P at rest (0.60 +/- 0.12 vs. 0.05 +/- 0.09) and after 60 min of exercise (1.00 +/- 0.12 vs. 0.36 +/- 0.11), but it did not differ at exhaustion. Neither respiratory exchange ratio nor respiratory quotient differed between trials at rest, after 60 min of exercise, or at exhaustion. Plasma free fatty acid, glycerol, beta-hydroxybutyrate, catecholamines, and insulin were similar during rest and exercise for both diets. Feeding DHAP for 7 days increased arm muscle glucose extraction before and during exercise, thereby enhancing submaximal arm endurance capacity.

Adult↗

Lipid-containing eye drops: a step closer to natural tears.

Disturbances of the lipid composition can, like mucin or fluid deficiency, cause 'dry eye'. The substitution of the lipids of the tear fluid has previously been unsatisfactory since eye ointments containing fats can lead to a considerable deterioration of the visual acuity due to the film of ointment resulting from an irregular spreading behavior. We proposed the introduction of physiological lipids that are normally present in tear fluid, such as phospholipids, saturated and unsaturated fatty acids and triglycerides, to provide lipid-containing eye drops. These best correspond to 'natural tears' and, due to the small size of the lipid particles, avoid a disturbance of the spreading behavior of the lipid layer. With lipid-containing eye drops of this kind, we carried out the following examinations: inquiry of patients' symptoms based on a standardized interview; Schirmer test under local anesthesia; break-up time (BUT); biomicroscopic evaluation of the lipid film, and stability tests as pH, gas chromatographic analysis of the fatty acid pattern and thin-layer chromatographic analysis of the lipid pattern. Schirmer test, BUT measurement and questioning about symptoms were undertaken after 1 week and then again after 3 weeks of treatment. All three parameters finally showed an improvement with a high statistical significance (p less than 0.001). The stability tests have shown that pH, lipid particle size, fatty acid and lipid composition of the examined lipid-containing eye drops were nearly unchanged till 4 months after preparation.

Administration, Topical↗

Nutrition and related claims used on packaged Australian foods--implications for regulation.

The aim of this study was to describe the use of nutrition and related claims on packaged food for sale in Australia and measure the compliance of such claims with regulations governing their use. A survey was conducted of the labelling of 6662 products in 40 different food categories on sale in New South Wales in 2001. Levels of compliance were assessed by comparing the claims on the label and data in the nutrition information panel with requirements of the Foods Standards Code and the Code of Practice on Nutrient Claims. Half of the products (51.3%) carried some type of nutrition related claim and 36.2% made at least one nutrient claim, with an average of 1.2 nutrition related claims on every food product. The foods with the highest use of nutrient claims were sports drinks, breakfast cereals, meat substitutes, pretzels and rice cakes, muesli bars and yoghurt. The most common nutrient claims were for fat, cholesterol, vitamins, minerals, and sugar. More than 20% of products carried claims related to additives. Many nutrient claims (12.9%) did not comply with current regulations, especially those in the voluntary Code of Practice. Adoption of mandatory requirements for all claims within the Food Standards Code may improve the levels of compliance. Implications for the regulation of nutrition and related claims are discussed. The impact of nutrition claims on consumer purchasing and consumption behaviour deserves further study.

Australia↗

Myocardial collagen turnover in normotensive obese patients: relation to insulin resistance.

OBJECTIVES: The present study was undertaken to assess the differential impact of insulin resistance, leptin and body composition on myocardial mass and serum markers of cardiac fibrosis in obese subjects, within a small range of elevated BMI (30-40 kg/m(2)), without pulmonary disease, cardiovascular disease, hypertension, cardiac hypertrophy or other cardiovascular disease. BACKGROUND: Obesity is an independent predictor of left ventricular mass (LVM) and is associated with disturbances in cardiac structure. The extent of the interstitial fibrosis in obese patients is not known, especially in the absence of cardiac hypertrophy. METHODS AND RESULTS: We included 160 obese subjects. The LVM was obtained using the Devereux formula. Body composition was estimated from a total body scan. Insulin sensitivity was assessed by homeostasis model assessment (HOMA), and cardiac collagen turnover by measurement of procollagen type III aminopeptide (PIIINP). PIIINP was correlated to the E/A ratio (r=0.24; P=0.012), a marker of ventricular function. PIIINP was independently correlated with glucose concentration (r=0.27; P=0.004), indexes of insulin resistance (HOMA (r=0.27; P=0.003), insulin (r=0.24; P=0.008)), and parameters associated with the insulin-resistance syndrome (HDL-cholesterol r=-0.27; P=0.004) and fat trunk/fat leg ratio (r=0.24; P=0.053)). The variable most correlated with PIIINP was HDL-cholesterol, followed by HOMA (r (2)=0.13). When HOMA was substituted for blood glucose concentration and insulinemia (Model 2), HDL-cholesterol was strongly related to lower PIIINP levels, followed by higher glucose concentration (r (2)=0.21). Regression analyses showed that LVM had the strongest independent positive correlation with fat-free mass (FFM) (r=0.39; P=0.0002), followed by systolic blood pressure (r=0.19; P=0.034). Neither adipose mass nor height independently added information to multivariate models. The ratio leptin/fat mass was correlated with LVM (r=-0.27; P=0.004), but not independently of the FFM. Markers for fibrosis were not significantly correlated with LVM. As a result, FFM was the most predictive factor of LVM in obese subjects. CONCLUSION: We found that serum levels of markers of cardiac collagen synthesis were significantly associated with insulin resistance in normotensive, nondiabetic obese subjects, and not related to the LVM. As a result, PIIINP could be a very early marker of ventricular dysfunction in these patients. Furthermore, we suggest that, for better detection of left ventricle hypertrophy in obese subjects, LVM should be indexed to FFM rather than to body surface area, or height.

Adult↗

Dietary fish oil effects on biliary lipid secretion and cholesterol gallstone formation in the African green monkey.

We studied two groups of adult male African green monkeys to assess the effects of dietary fish oil on biliary lipid secretion and cholesterol gallstone formation. One group was fed 0.8 mg cholesterol/kcal and 42% of calories as fat with half of the fat calories derived from lard; the other group was fed a similar diet except for the isocaloric substitution of menhaden oil for lard. After 2 1/2 to 3 yr, necropsies were performed and the presence of gallstones was determined. Gallbladder bile specimens were analyzed for cholesterol saturation index, as well as for bile acid species and biliary phospholipid fatty acid composition. Our results showed that 67% of animals fed the lard diet had cholesterol gallstones compared with only 22% of animals in the group fed the fish oil diet (p = 0.08). The cholesterol saturation index of gallbladder bile also tended to be higher in the lard-fed group (1.15 +/- 0.11) compared with the fish oil-fed group (0.86 +/- 0.09, p = 0.06). No differences between the two dietary groups were noted in the percentages of the various types of bile acids. However, a greater percentage of omega-3 fatty acids and a lesser percentage of 18:1, 18:2 and 20:4 fatty acids were found in the biliary phospholipids from the fish oil-fed group compared with the lard-fed group. Biliary lipid secretion rates were then measured during isolated recirculating liver perfusion performed with a constant sodium taurocholate infusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Nutritive value of potato processing wastes in total mixed rations for dairy cattle.

The nutritive value of wet potato processing waste for dairy cattle was determined in two experiments. In Experiment 1, rations contained, on a dry matter basis, 0, 10, 15, and 20% potato waste and were substituted for high moisture corn in diets for 32 lactating Holstein cows for 12 wk. Substituting potato waste for corn did not significantly affect milk yield, milk composition, milk production persistency, or dry matter intake. Cows fed 20% potato waste tended to decrease in milk fat percent and to shift molar proportions of rumen volatile fatty acids toward a decrease in acetate: propionate ratio. In Experiment 2, six steers were used in a 3 X 3 Latin square design to test digestibility and nitrogen utilization of potato waste substituted for high moisture corn at 0, 10, and 20% of the ration dry matter. A second group of four steers with rumen fistulas were used in a 4 X 4 Latin square to test rumen fermentation parameters. Diets contained 0, 10, 20, and 30% potato wastes and were similar to Experiment 1. Potato waste did not significantly affect digestibility of crude protein or dry matter, but at 20% substitution digestibility of acid detergent fiber decreased. Rumen ammonia, acetate, acetate to propionate ratios, and total volatile fatty acids were lower at high intakes of potato waste and pH was increased. The shift in rumen fermentation when large amounts of potatoes were fed explains the depressed butter fat on these rations.

Animal Feed↗

Soy-enhanced lunch acceptance by preschoolers.

OBJECTIVE: To evaluate acceptance of soy-enhanced compared with traditional menus by preschool children. Soy-enhanced foods were substituted on a traditional cycle menu, and the amount eaten, energy, and nutrient values for traditional and soy-enhanced lunches were compared. DESIGN: A traditional three-week cycle menu, using the Child and Adult Care Food Program (CACFP) meal pattern guidelines, was used to develop a comparable soy-enhanced menu. Traditional and soy-enhanced lunches were randomly assigned to respective days. Foods were portioned onto individual plates using standardized measuring utensils. Individual plate waste techniques were used to collect food waste. Subjects/setting Participants were preschool children, three to six years of age and of white and Hispanic origin, attending a part-day Head Start program. Statistical analyses performed Analysis of covariance was used to adjust lunch and food intakes for differences in average amounts of foods served. The Nutrient Data System was used to calculate energy and nutrient content of lunches. Analysis of variance was used to calculate differences in amounts eaten, energy values, and nutrient values of traditional and soy-enhanced lunches and foods. Data analyses were performed with the Statistical Analysis Software (version 8.0, 1999, SAS Institute, Cary, NC). RESULTS: Soy-enhanced foods were successfully substituted for 23 traditional foods included in the cycle menus. Soy-enhanced foods tended to be higher in energy, protein, and iron. Traditional lunches tended to be higher in fat, saturated fat, and vitamin A. Consumption was significantly less for energy, protein, fiber, and iron from foods eaten from traditional compared with soy-enhanced lunch menus. Applications/conclusions Acceptance of soy-enhanced lunches was shown because there were no significant differences in the average amount eaten (grams per meal) between traditional and soy-enhanced lunches. Preschool programs can substitute soy-enhanced for traditional foods, which will add variety to the diet without sacrificing taste, energy, or nutrient value. The fat and energy content of the lunches was higher than recommended, and soy-enhanced foods were not always lower in fat. There is a need for the food industry and foodservice personnel to address the energy and fat content of all foods served in lunches to preschool children because a few extra calories added to the daily intakes can contribute to weight gain.

Analysis of Variance↗

The Limulus Amoebocyte Lysate (LAL) assay for the detection of endotoxin in fat emulsions for total parenteral nutrition (TPN).

Fat emulsions spiked with Escherichia coli endotoxin were tested with Limulus Amoebocyte Lysate (LAL) reagent, using both the micro method and the tube method. The effect of vortexing, ultrasonication and addition of Pyrosperse on the dispersion of endotoxin in these emulsions was compared. The advantage of using the tube method, rather than the micro method, is shown. Ultrasonication may substitute vortex mixing. Pyrosperse had no convincing effect.

Endotoxins↗

Esterification of free fatty acids in adipocytes: a comparison between octanoate and oleate.

Medium-chain triacylglycerols (MCT) are present in milk, coconut oil and other foods, and are used therapeutically in special diets for certain disorders of lipid and glucose utilization. Recently, it has become apparent that MCT are not only oxidized in the liver, but are also present in lymph and fat tissue, particularly after chronic treatment. To evaluate the influence of MCT on metabolism in fat cells, we compared incorporation of octanoate and oleate into cellular triacylglycerols of 3T3-L1 adipocytes as well as their effects on preadipocyte differentiation. We found that less octanoate than oleate was stored and that more octanoate than oleate was oxidized. Octanoate was esterified to a greater extent at the sn-1,3 position of glyceryl carbons than at the sn-2 position, whereas the opposite was true for oleate. Glycerol release from fat cells pre-treated with octanoate was also greater than from cells pre-treated with oleate, presumably related to the preferential release of octanoate from the sn-1,3 position. Octanoate was not incorporated into lipids in undifferentiated cells and did not induce differentiation in these cells, whereas oleate was readily stored and actually induced differentiation. Incorporation of octanoate into lipids increased as cells differentiated, but reached a maximum of about 10% of the total stored fatty acids. If these effects in vitro also occur in vivo, substitution of octanoate for oleate or other long-chain fatty acids could have the beneficial effect of diminishing fat-cell number and lipid content.

3T3 Cells↗

Leptin predicts bone and fat mass after accounting for the effects of diet and glucocorticoid treatment in piglets.

The role of leptin in neonatal growth and bone metabolism has been investigated, but not simultaneously. The objectives of this study were to determine if leptin relates to bone mass during rapid growth; if consumption of maternal milk is related to elevated circulating concentrations of leptin resulting in higher fat mass; and if glucocorticoids result in higher fat mass and reduced bone mass due to elevated leptin. Thirty-two piglets were randomized to either a suckling or milk substitute plus either dexamethasone (DEX) or placebo injection for 15 days beginning at 5 days of age. Milk and blood samples were obtained at baseline, and after 15 days, blood was sampled again for measurement of leptin and bone biochemistry. Weight at baseline plus weight and length after 15 days were recorded, followed by measurement of whole body bone mineral content, bone area, and fat mass using dual energy x-ray absorptiometry. At baseline, plasma leptin was elevated in suckled piglets. Piglets that suckled had elevated fat mass as did those who received DEX. However, DEX resulted in suppressed weight and length, bone mass, and bone metabolism. Leptin was similar among groups after the 15 days. After accounting for body size and treatment effects, piglet plasma leptin was predictive of bone and fat mass. Leptin circulating early postnatally is linked to body composition, specifically fat and bone mass. Elevations in fat mass and reductions in bone mass observed after 15 days of DEX treatment are not related to leptin metabolism. Both human and porcine neonates share similar characteristics with respect to relationships of leptin with fat and bone mass.

Adipose Tissue↗

A new polymorphic site located in the human UCP1 gene controls the in vitro binding of CREB-like factor.

Uncoupling protein 1 (UCP1) is uniquely expressed in brown adipose tissue (BAT) and generates heat by uncoupling respiration from ATP synthesis. A defect in BAT thermogenesis has been described in different models of rodent obesity. In humans, the implication of BAT in energy expenditure is still under discussion. A BclI polymorphism associated with fat gain over time has been described in the upstream region of the human UCP1 (hUCP1) gene. In this study, a new polymorphic site linked to the BclI site is described which results in a C to A point mutation, 89 bp downstream of the BclI site, ie at position -3737 bp. This site is located in the recently analysed regulatory region of the hUCP1 gene. The mutation disrupts a consensus site for the binding of ATF/CREB transcription factor family and inhibits the factor binding in vitro. However, transient transfection of a rodent brown adipocyte cell line shows that the isoproterenol (ISO) stimulation of the hUCP1 gene transcription is not significantly affected by this mutation. However, we postulate that the C/A substitution, in human, may contribute to a minor defect in the regulation of hUCP1 transcription and that would explain fat gain over time.

Adipose Tissue, Brown↗