Hotspots of microplastic accumulation at the land-sea transition and their spatial heterogeneity: The Po River prodelta (Adriatic Sea).

Deltas are the locus of river-borne sediment accumulation, however, their role in sequestering plastic pollutants is still overlooked. By combining geomorphological, sedimentological, and geochemical analyses, which include time-lapse multibeam bathymetry, sediment provenance, and µFT-IR analyses, we investigate the fate of plastic particles after a river flood event providing an unprecedented documentation of the spatial distribution of sediment as well as of microplastics (MPs), including particles fibers, and phthalates (PAEs) abundances in the subaqueous delta. Overall sediments are characterized by an average of 139.7 ± 80 MPs/kg d.w., but display spatial heterogeneity of sediment and MPs accumulation: MPs are absent within the active sandy delta lobe, reflecting dilution by clastic sediment (ca. 1.3 Mm3) and sediment bypass. The highest MP concentration (625 MPs/kg d.w.) occurs in the distal reaches of the active lobe where flow energy dissipates. In addition to MPs, cellulosic fibers are relevant (of up to 3800 fibers/kg d.w.) in all the analyzed sediment samples, and dominate (94 %) with respect to synthetic polymers. Statistically significant differences in the relative concentration of fiber fragments ≤0.5 mm in size were highlighted between the active delta lobe and the migrating bedforms in the prodelta. Fibers were found to slightly follow a power law size distribution coherent with a one-dimensional fragmentation model and thus indicating the absence of a size dependent selection mechanism during burial. Multivariate statistical analysis suggests traveling distance and bottom-transport regime as the most relevant factors controlling particle distribution. Our findings suggest that subaqueous prodelta should be considered hot spots for the accumulation of MPs and associated pollutants, albeit the strong lateral heterogeneity in their abundances reflects changes in the relative influence of fluvial and marine processes.

[Importance of the post-prandial glycemia in the management of type 2 diabetes]. / Importance de la glycémie postprandiale dans la prise en charge du diabète de type 2.

Cardiovascular disease is the main cause of mortality in diabetic patients. The risk of cardiovascular disease occurs at a lower glycemic level compared to microvascular complications. Post-prandial hyperglycemia seems to play a major role in the development of atherosclerotic lesions. In this article we review the evidence regarding the prognostic value of post-challenge hyperglycaemia relative to the risk of cardiovascular disease, explore the physio-pathologic mechanisms responsible for the negative effects of post-prandial hyperglycaemia and detail the benefits of treatment aimed at controlling post-prandial glycaemia.

[Diabetes mellitus and driving]. / Diabète sucré et conduite automobile.

Most studies, which are retrospective, show contradictory results regarding the incidence of road traffic accident among diabetic patients. The most frequent cause of accident is hypoglycemia. One should also consider impaired vision (retinopathy, maculopathy), neuropathy (feet insensitivity) and sleep apnoea in overweight patients. Hypoglycemia not only leads to impaired judgement during driving, but also to a reduction in performances, frequent hypoglycemias impair symptom recognition and increase the risk of loss of consciousness. Patients should benefit from teaching about hypoglycemia, i.e. how to recognize and correct it in order to avoid accidents. Generally they should not drive if their glycemia is under 5 mmol/l without correcting it with an adequate amount of carbohydrates.

ESPEN Guidelines on Enteral Nutrition: Cardiology and pulmonology.

These guidelines are intended to give evidence-based recommendations for the use of enteral nutrition (EN) in patients with chronic heart failure (CHF) and chronic obstructive pulmonary disease (COPD). They were developed by an interdisciplinary expert group in accordance with officially accepted standards and are based on all relevant publications since 1985. They have been discussed and accepted in a consensus conference. EN by means of oral nutritional supplements (ONS) or tube feeding (TF) enables nutritional intake to be maintained or increased when normal oral intake is inadequate. No data are yet available concerning the effects of EN on cachexia in CHF patients. However, EN is recommended to stop or reverse weight loss on the basis of physiological plausibility. In COPD patients, EN in combination with exercise and anabolic pharmacotherapy has the potential to improve nutritional status and function. Frequent small amounts of ONS are preferred in order to avoid postprandial dyspnoea and satiety as well as to improve compliance.

Lipid and carbohydrate metabolism in IDDM during moderate and intense exercise.

Insulin-dependent diabetes mellitus (IDDM) is characterized by a metabolic and hormonal disarray that may be more evident during exercise. However, the metabolic response to exercise of different intensities has not been evaluated in IDDM. We therefore used stable isotope techniques and indirect calorimetry to quantify substrate kinetics and oxidation during 30 min of exercise at 45 and 75% of maximal oxygen uptake (Vo2max) in seven men with IDDM (D group) infused with insulin at a constant basal rate. Normal control subjects (C group) matched for age, weight, and Vo2max were also studied. During moderate exercise, glucose uptake (Rd) was lower in the D than in the C group (15.3 +/- 1.0 vs. 20.8 +/- 1.6 mumol.min-1.kg-1; P < 0.05). Carbohydrate oxidation also tended to be lower in the D group (71.0 +/- 7.2 vs. 87.5 +/- 10.6 mumol.min-1.kg-1; P = 0.08). The D group relied on fat oxidation to a greater extent than did the C group (16.9 +/- 1.1 vs. 10.4 +/- 1.6 mumol.min-1.kg-1; P < 0.05). The enhanced fat oxidation was not due to increased lipolysis because no differences occurred in glycerol release (Ra) or in plasma free fatty acid Ra or concentration, and the source of the extra lipid appeared to be intramuscular fat stores. These differences in substrate metabolism were not evident during exercise at 75% of Vo2max. The lower glucose uptake and oxidation in the diabetic subjects during moderate, but not intense, exercise suggest that glucose metabolism is regulated differently depending on exercise intensity.(ABSTRACT TRUNCATED AT 250 WORDS)

A tracer investigation of obligatory oxidative amino acid losses in healthy, young adults.

BACKGROUND: Estimation of the minimum requirement for indispensable amino acids (IAAs) has been attempted by assuming that obligatory oxidative losses (OOLs) of IAAs can be approximated from nitrogen losses and that the efficiency of utilization of IAAs at requirement intakes is approximately 70%. OBJECTIVE: We wished to determine the rates of OOLs in healthy adults, using L-[1-(13)C]leucine and L-[1-(13)C, methyl-(2)H(3)]methio-nine as tracers, after adjustment to a protein-free diet and how these rates compare with those when either sulfur amino acids (SAAs: methionine and cyst(e)ine) or leucine were removed from an otherwise adequate diet. DESIGN: Eleven subjects were randomly assigned to a 5-d protein-free diet or a 5-d diet providing adequate nitrogen and amino acids except for the SAAs or leucine. A 24-h constant intravenous infusion of [(15)N, (15)N]urea and L-[1-(13)C]leucine (Leu group; n = 5) or L-[1-(13)C, methyl-(2)H(3)]methionine (Met group; n = 6 ) began at 1800 on day 5 and rates of amino acid oxidation were determined. RESULTS: Mean (+/-SD) oxidation rates (mg kg(-)(1) d(-)(1)) of methionine and leucine were 6.4 +/- 1.4 and 24.7 +/- 3.6, respectively, with the protein-free diet; rates were significantly lower (3.9 +/- 2.2 and 7. 2 +/- 3.4, respectively) after the SAA- and leucine-free diets. Urea production was significantly lower (P < 0.01) with the protein-free than with the SAA- or leucine-free diet. CONCLUSIONS: Isotopically determined OOLs for methionine and leucine are consistent with losses predicted from nitrogen excretion, and consistent with our previous measurements of cysteine oxidation as an index of total SAA losses. The data further support our earlier conclusions regarding methionine sparing by cysteine and tentative recommended SAA requirements in adults.

Effect of cystine intake on methionine kinetics and oxidation determined with oral tracers of methionine and cysteine in healthy adults.

There is evidence based on nitrogen balance that dietary cystine spares, from approximately 16% to 89%, the total methionine requirement. In a previous study we did not detect, by tracer techniques, a sparing effect of cystine when the diet provided methionine at a limiting intake (requirement level: 13 mg.kg-1.d-1). One reason could be that we used an intravenous infusion of the tracer, which may not, therefore, have labeled the carbon dioxide derived from the splanchnic oxidation of dietary methionine. The aim of this study was to compare methionine metabolism and oxidation in eight healthy adults given for 6 d each of three different diets: 13 mg (87.0 mumol) methionine.kg-1.d-1 and no cystine (diet A); 5 mg (33.5 mumol) methionine.kg-1.d-1 and no cystine (diet B); and 5 mg (33.5 mumol) methionine.kg-1.d-1 and 6.5 mg (52.4 mumol) cystine.kg-1.d-1 (diet C). On day 7, tracers ([1-13C, methyl-2H3]methionine and [2H2]cysteine) were administered orally at 30-min intervals for 8 h. Blood and breath samples were obtained for analysis during 3-h fasting and consecutive 5-h feeding periods. During fasting, methionine oxidation and methionine methyl (Qm) and carboxyl (Qc) fluxes and plasma concentrations were not affected by the amount of sulfur amino acids in the three diets. In the fed state methionine oxidation was significantly lower during diets B (3.0 +/- 0.5 mumol.kg-1.h-1) and C (2.8 +/- 0.6 mumol.kg-1.h-1) than during diet A (4.1 +/- 0.9 mumol.kg-1.h-1); there were no significant differences between diets B and C. Qm and Qc decreased with decreased methionine intake but no effect was observed by adding cystine. Cysteine flux (Qcys) was not affected by diet composition but it was lower during feeding than during fasting. In conclusion, replacing approximately 60% of the total requirement for methionine with cystine over a short diet period did not result in a detectable sparing of methionine oxidation.

Cysteine kinetics and oxidation at different intakes of methionine and cystine in young adults.

BACKGROUND: We previously studied methionine kinetics and oxidation with the tracer L-[1-(13)C, methyl-(2)H(3)]methionine. OBJECTIVES: We sought to explore methionine-cysteine interrelations in adults by using L-[1-(13)C]cysteine under different dietary conditions. DESIGN: In experiment 1, 12 adults consumed a protein-free diet for 6 d. On day 7, methionine (n = 6) or cysteine (n = 6) oxidation rates were measured during an 8-h continuous infusion of L-[1-(13)C, methyl-(2)H(3)]methionine or L-[1-(13)C]cysteine, respectively. In experiment 2, 6 young men consumed 3 diets for 6 d each before a tracer study on day 7 with L-[1-(13)C]cysteine. The amounts (in mg*kg(-)(1)*d(-)(1)) of methionine and cysteine, respectively, were: high-methionine (HM) diet, 13 and 0; low-methionine (LM) diet, 6.5 and 0; and methionine-plus-cystine (MC) diet, 6.5 and 5.6. Cysteine flux and oxidation rates were determined and sulfur amino acid (SAA, methionine plus cysteine) balances were estimated. RESULTS: In experiment 1, rates of methionine and cysteine oxidation were similar to losses predicted from obligatory nitrogen losses. In experiment 2, SAA balance was less negative when subjects consumed the HM diet than the LM and MC diets (interaction, P = 0.034), largely because of a difference in fed-state balance (HM compared with LM, P < 0.01; HM compared with MC, P < 0.05). There was no evidence of a sparing effect of dietary cystine on the methionine requirement. CONCLUSION: These studies support use of [1-(13)C]cysteine for studying whole-body SAA oxidation and conclusions that maintenance of SAA balance is best achieved by supplying methionine at approximately the FAO/WHO/UNU recommendations for total SAA intake (13 mg*kg(-)(1)*d(-)(1)).

Glucose-induced thermogenesis in postobese women who have undergone biliopancreatic diversion.

We evaluated the metabolic response to a standard (75-g) oral-glucose-tolerance test (OGTT) in eight post-obese women (PO) who underwent biliopancreatic diversion and in eight healthy control women (C). All subjects had been weight-stable for > or = 2 y. Blood samples for glucose, insulin, C-peptide, and nonesterified free fatty acids were taken at baseline and during 180 min after the glucose load. Plasma glucose and insulin concentrations at baseline and during the OGTT were similar in the two groups, suggesting the absence of an insulin-resistant state in the PO. Continuous indirect calorimetry was performed throughout the test. Glucose-induced thermogenesis (GIT) was higher in PO than in C (8.6 +/- 2.6 vs 4.3 +/- 1.9%; P < 0.01). These data indicate that GIT and insulin-glucose metabolism are not impaired in postobese patients when a near ideal body weight is reached and maintained after weight loss; this suggests that thermogenic deficiencies and hyperinsulinemia-insulin resistance are alterations secondary to obesity.

Leucine kinetics in reference to the effect of the feeding mode as three discrete meals.

In a recent study, we observed that the 24-hour leucine oxidation measured when three equal meals providing a generous intake of leucine (approximately 90 mg x kg(-1) x d(-1)) are eaten during the day is 16% lower (P < .01) than that for the same diet given as 10 hourly, equal meals. We hypothesized that the pattern of meal intake at a lower level of dietary leucine would affect the 24-hour rate of leucine oxidation and possibly improve the retention of dietary leucine. A total of 11 healthy adults participated in this investigation. The daily leucine intake was 182 micromol x kg(-1) x d(-1) (38 mg x kg(-1) x d(-1)) given with an L-amino acid diet. All subjects received three discrete meals daily for 6 days prior to a 24-hour intravenous (IV) tracer infusion of L-[1-13C]-leucine on day 7 (study 1). Four of these subjects participated in two additional studies of similar design. Study 2 involved giving [1-13C]-leucine as a constant IV infusion together with tracer added to the amino acid mixture at each meal time. In study 3, subjects received the three meals with added [1-13C]-leucine tracer while [2H3]-leucine was given as a constant IV infusion. Total leucine oxidation in studies 1 and 2 was 238+/-66 and 231+/-85 micromol x kg(-1) x d(-1), respectively. Leucine balance was positive, amounting to 18% of the total (diet + tracer) intake. The estimated mean nitrogen balance was +8 mg x kg(-1) x d(-1). Leucine oxidation was higher (P < .01) for breakfast than for the lunch meal. This difference was associated with lower insulin and higher plasma leucine concentrations at breakfast versus lunch periods. The results from study 3 suggest that the higher rate of leucine oxidation observed at breakfast as compared with lunch is not due to a difference in the immediate splanchnic fate of absorbed leucine from each meal. In comparison to our previous small frequent-meal studies, the pattern of meal feeding influences overall leucine utilization at both generous and limiting leucine intakes. Hence, it is possible that the pattern of meal feeding may affect estimations of amino acid requirements using the tracer-balance approach. Longer-term dietary studies will be needed to establish whether and the extent to which this is so.

Effect of theophylline on substrate metabolism during exercise.

We tested the hypothesis that adenosine is involved in regulating substrate metabolism during exercise. Seven trained cyclists were studied during 30 minutes of exercise at approximately 75% maximal oxygen uptake (VO2max). Lipid metabolism was evaluated by infusing [2H5]glycerol and [1-13C]palmitate, and glucose kinetics were evaluated by infusing [6,6-2H]glucose. Fat and carbohydrate oxidation were also measured by indirect calorimetry. The same subjects performed two identical exercise tests, but in one trial theophylline, a potent adenosine receptor antagonist, was infused for 1 hour before and throughout exercise. Theophylline did not increase whole-body lipolysis (glycerol rate of appearance [Ra]) or free fatty acid (FFA) release during exercise, but fat oxidation was lower than control values (9.5 +/- 3.0 v 18.0 +/- 4.2 micromol x min(-1) x kg(-1), P < .01). Glucose Ra was not affected by theophylline infusion, but glucose uptake was lower (31.6 +/- 4.1 v 40.4 +/- 5.0 micromol x min(-1) x kg(-1), P < .05) and glucose concentration was higher (6.4 +/- 0.6 v 5.8 +/- 0.4 mmol/L, P < .05) than in the control trial. Total carbohydrate oxidation (302.3 +/- 26.2 v 265.5 +/- 11.7 micromol x min(-1) x kg(-1), P < .06), estimated muscle glycogenolysis (270.7 +/- 23.1 v 225.1 +/- 9.7 micromol x min(-1) x kg(-1), P < .05), and plasma lactate concentration (7.9 +/- 1.6 v 5.9 +/- 1.1 mmol/L, P < .001) were also higher during the theophylline trial. These data suggest that adenosine may play a role in stimulating glucose uptake and restraining glycogenolysis but not in limiting lipolysis during exercise.

Fat metabolism during high-intensity exercise in endurance-trained and untrained men.

To determine whether trained individuals rely more on fat than untrained persons during high-intensity exercise, six endurance-trained men and six untrained men were studied during 30 minutes of exercise at 75% to 80% maximal oxygen consumption (VO2max). The rates of appearance (Ra) and disappearance (Rd) of glycerol and free fatty acids (FFAs) were determined using [1,1,2,3,3-2H]glycerol and [1-13C]palmitate, respectively, whereas the overall rate of fatty acid oxidation was determined using indirect calorimetry. During exercise, the whole-body rate of lipolysis (ie, glycerol Ra) was higher in the trained group (7.1 +/- 1.2 v 4.5 +/- 0.7 micromol x min(-1) x kg(-1), P < .05), as was the Ra (approximately Rd) of FFA (9.0 +/- 0.9 v 5.0 +/- 1.0 micromol x min(-1) x kg(-1), P < .001). FFA utilization was higher in trained subjects even when expressed as a percentage of total energy expenditure (10% +/- 1% v 7% +/- 1%, P < .05). However, this difference in plasma FFA flux could not account for all of the difference in fatty acid oxidation between trained and untrained subjects (20.8 +/- 3.3 v 7.9 +/- 1.6 micromol x min(-1) x kg(-1), or 23% +/- 3% v 13% +/- 2% of total energy expenditure, both P < .05). Thus, the oxidation of fatty acids derived from some other source also must have been greater in the trained men. We conclude that trained athletes use more fat than untrained individuals even during intense exercise performed at the same percentage of VO2max. The additional fatty acids appear to be derived from both adipose tissue and, presumably, intramuscular triglyceride stores.

Glucose kinetics during high-intensity exercise in endurance-trained and untrained humans.

In humans, endurance training reduces the rates of glucose production and utilization during moderate-intensity exercise. It is uncertain, however, whether this is also true during high-intensity exercise. Accordingly, we studied eight endurance-trained cyclists and eight untrained subjects during 30 min of cycling at approximately 80% of maximal oxygen uptake (VO2max). Rates of glucose appearance (Ra) and disappearance (Rd) were determined using a primed, continuous infusion of [6,6-2H]glucose. Average glucose Ra during exercise did not differ in the trained and untrained subjects (34.3 +/- 3.6 vs. 36.0 +/- 1.7 mumol.min-1.kg-1; mean +/- SE; P, not significant). Plasma insulin, glucagon, norepinephrine, and epinephrine concentrations were also similar in the two groups. In contrast, glucose Rd during exercise was 19% lower in the trained compared with the untrained subjects (27.0 +/- 2.6 vs. 33.2 +/- 1.5 mumol.min-1.kg-1; P < 0.001). Consequently, during exercise, plasma glucose concentration rose significantly (P < 0.05) in the trained subjects but did not change in the untrained subjects. We conclude that utilization of plasma glucose is lower in trained subjects during high-intensity exercise, even when the exercise is performed at the same relative (and therefore a higher absolute) intensity as in the untrained state. Hyperglycemia in trained subjects during intense exercise appears to be due to this lower rate of glucose utilization rather than a higher rate of glucose production.

A rapid GLC method for the direct analysis of plasma medium chain fatty acids.

A new, rapid, gas-liquid-chromatographic (GLC) method for the direct determination of plasma medium-chain fatty acids (MCFA) (from C8 to C12) which does not require derivatization procedures is described. Analysis of underivatized MCFA by GLC showed a detection limit ranging from 0.50 to 0.217 microgram depending on chain length: the longer the chain, the higher the detection limit. Compared with the HPLC and GLC methods currently described in the literature, this GLC procedure appears to be easy, adequately sensitive, accurate and well reproducible for those MCFA, like n-octanoic and n-decanoic acids, present in plasma after p.o. or i.v. MCT administration and it requires a short time (about 30 min) for complete processing.

Protective effects of recombinant growth hormone on intestinal mucosa in rats receiving abdominal radiotherapy.

BACKGROUND AND AIMS: Radiation injury to the gut induces nutrient losses that compromise the body ability to adequately fight infection, heal wounds and recover from illness. Recombinant growth hormone (rhGH), is known to enhance anabolism, therefore, we tested the hypothesis that rhGH preserves whole body growth and trophism of the jejunum and ileum of irradiated rats. METHODS: After acclimatization period, the rats were divided in three groups: (1). control rats (C), (2). rats irradiated with a single dose of 10 Gy (group A); (3). rats irradiated with a single dose of 5 Gy (Group B); after irradiation, rats were given subcutaneously (sc) saline or 0.25 or 0.50 mg rhGH/kg BW/d for the following 6 days. Body weight changes were recorded during this time. On day 6 post-radiation, rats were killed and small intestine mucosa dry and wet weights were measured, as well as mucosa protein content. RESULTS: Group A rats lost body weight during the 6-day post-radiation period, regardless of rhGH treatment and dosage. rhGH was effective in preventing weight loss and normalizing growth in group B rats (saline 23.1+/-11.1, vs. controls P<0.05; rhGH: 35.0+/-10.0 g BW/d, vs. controls P = ns). Trophic effect of rhGH was observed on mucosa weight and mucosa protein content in rats irradiated with 5 Gy, but not in those receiving 10 Gy. CONCLUSION: rhGH seems to normalize growth and mucosa protein content in irradiated rats. However, rhGH beneficial effects were observed only in rats receiving the lower dose of radiation.

Food intake in 1707 hospitalised patients: a prospective comprehensive hospital survey.

BACKGROUND & AIMS: This study aimed to assess the ability of the hospital meal service to meet patients' nutritional needs. METHODS: All hospitalised patients who received 3 meals/day without artificial nutritional support were included. The nutritional values of food served, consumed and wasted during a 24 h period were compared to patients' needs estimated as energy: 110% Harris-Benedict formula; protein: 1.2 or 1.0 g/kg bodyweight/day for patients < or = or > 65 years old, respectively. A structured interview recorded patients' evaluation of the meal quality, their reasons for non-consumption of food and the relationship between food intake and disease. RESULTS: Out of 1707 patients included, 1416 were fully assessable (59% women; 68+/-21 years; body mass index: 24.3+/-5.1 kg/m(2)). Daily meals provided 2007+/-479 kcal and 78+/-21 g of protein and exceeded patients' needs by 41% and 15%, respectively. However, 975 patients did not eat enough. Plate waste was 471+/-372 kcal and 21+/-17 g of protein/day/patient. Moreover, the food intake of 572 (59%) of these underfed patients was not predominantly affected by disease. Logistic regression analyses identified as other risk factors: elevated BMI, male gender, modified diet prescription, length of stay <8 or > or = 90 days and inadequate supper. CONCLUSION: Despite sufficient food provision, most of the hospitalised patients did not cover their estimated needs. Since insufficient food intake was often attributed to causes other than disease, there should be potential to improve the hospital meal service.

Twenty-four-hour energy and nutrient balance in weight stable postobese patients after biliopancreatic diversion.

To better understand the long-term weight stability of postobese patients who underwent biliopancreatic diversion (BPD), we studied 24-h energy and nutrient balance in eight women at least 3 yr after surgery (PO) and compared the results to those obtained in eight normal never-obese control women (C), matched by age and weight. Body composition was measured by dual-energy x-ray absorptiometry (DXA). All the patients were on an ad libitum diet; 24-h energy and nutrient intake were measured on the experimental day. Twenty-four-hour energy expenditure (EE) and 24-h nutrient oxidation rates were measured in a respiratory chamber, and energy and nutrient balances were calculated after correcting for 24-h fecal nutrient loss. No differences in body composition were found between PO and C. PO had a higher gross energy intake than C (10.6 +/- 3.4 vs. 8.0 +/- 2.2 MJ/d; p < 0.05); however, due to the higher energy fecal loss in PO as compared to C (2.4 +/- 1.3 vs. 0.09 +/- 0.01 MJ/day; p < 0.01), 24-h metabolizable energy intake (MEJ) was not different in the two groups. The energy fecal loss in the PO patients was mostly in the form of lipid. EE at 24 h was not different in PO as compared to C. Therefore energy balance, computed as the difference between 24-h MEI and 24-h EE, was similar in the two groups. Respiratory quotient was significantly higher in PO than in C (1.00 +/- 0.08 vs. 0.83 +/- 0.03; p < 0.01). Carbohydrate (-135 +/- 37 g/d in PO vs. 63 +/- 23 g/d in C; p < 0.001), and lipid (48 +/- 14 g/d in PO vs. -23 +/- 6 g/d in C; p < 0.001) balances were different in the two groups. We conclude that chronic lipid malabsorption was the main metabolic abnormality explaining the achievement of energy balance in postobese subjects after biliopancreatic diversion. A chronic reduction of lipid absorption seems to play a key role in the long-term weight stability of this group of postobese subjects.

Parenteral nutrition practices in hospital pharmacies in Switzerland, France, and Belgium.

OBJECTIVE: Important changes in administering total parenteral nutrition (PN) admixtures have occurred over the past decade. This study describes hospital pharmacists' practices in France (F), Switzerland (CH), and Belgium (B). METHODS: From the responses received using a standardized questionnaire, (n = 378) we determined the origin, types of container used, and choice of PN formula (standard versus tailor-made) and the type of quality control and the existence of nutrition support teams. RESULTS: The mean response rates were 55.6% (CH), 30.5% (F), and 24.5% (B). Standard formulas were used mainly for adult patients (CH, 86%; F, 79%; B, 86%), whereas approximately 50% of tailor-made PN bags were used for children. Single-compartment or multicompartment bags or glass bottles contained standard formulas. Most standard formulas were provided by industry, apart from (B), where 50% of PN solutions were compounded by hospital pharmacies. Single-compartment bags contained generally tailor-made formulas produced exclusively by hospital pharmacies in (CH) and (B), whereas 33% were provided by industry in (F). Quality controls were mostly visual and occurred in 75% to 95% of hospitals. Nutrition support teams were present in 32% to 45% of hospitals. CONCLUSION: The choice, origin, and type of container used for PN formulas were highly variable among countries. However, the use of standard formulas in bags was predominant in (CH) and (B). The function of nutrition support teams was similar in (F), (CH), and (B).

Kinetics and thermogenesis of medium-chain monocarboxylic and dicarboxylic acids in man: sebacate and medium-chain triglycerides.

The effects on oxygen consumption and carbon dioxide production of a constant intravenous infusion of 0.15 g of disodium sebacate (Sb), the sodic salt of a medium-chain dicarboxylic acid with 10 carbon atoms, per kilogram of body weight per hour over 5 hours and a 50% mixture of medium- and long-chain triglycerides (MCT/LCT) were compared in 10 healthy men. Oxygen consumption and carbon dioxide production were measured by indirect calorimetry. Mean oxygen consumption was about 19% higher than the basal oxygen consumption at the end of MCT/LCT infusion but was only 5% higher than the basal oxygen consumption when Sb was infused. There was an eightfold increase in plasma beta-hydroxybutyrate and acetoacetate concentrations and a threefold increase in serum insulin levels during MCT/LCT infusion, but no significant change in ketone bodies and insulin from basal values was observed during and after Sb infusion. Pharmacokinetic parameters were also computed, showing an average apparent volume of distribution of 167 mL/kg of body weight for MCTs and 112 mL/kg of body weight for Sb. The t1/2 of MCTs was 50 minutes and that of Sb was 78 minutes. Urinary excretion of Sb and its beta-oxidative by-product, suberic acid, globally accounted for 48% of the given amount of Sb. In spite of its urinary loss and slower tissue uptake compared with MCTs, Sb avoided ketone body formation or elevation in insulin levels and did not induce a significant increase in oxygen consumption.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetic profile of dodecanedioic acid, a proposed alternative fuel substrate.

Dodecanedioic acid (C12), a saturated, aliphatic dicarboxylic acid with 12 carbon atoms, was given as an intravenous bolus (800 mumol/kg of body weight [kgBW]) in male Wistar rats to study its pharmacokinetic profile. Because total plasma C12, which results from the sum of both free and albumin binding fractions, was measured by high-performance liquid chromatography, an in vitro experimental session was carried out to determine the binding curve of C12 in rat plasma. These data were then used to calculate the plasma C12 free fraction in in vivo experiments. The best fit obtained for the experimental data of albumin binding was obtained with the equation of reversible, saturable binding to one, two, or three classes of noninteracting equivalent sites. Only a single binding site was clearly identified with a dissociation constant of 147 mumol/L and a maximal predicted binding of 1.57 mol/mol albumin. The urinary excretion of C12 was 3.90 +/- 1.62% of the administered dose. The pharmacokinetic analysis was performed by one-compartment model with linear transfer to the tissues, taking into account simultaneously both plasma concentration and urine excretion data. The apparent volume of distribution of C12 was 0.248 +/- 0.035 L/kgBW, the apparent first order rate constant to the tissues was 0.0535 +/- 0.0123 min-1 and that from plasma to urine was 0.00206 +/- 0.00051 min-1. The C12 plasma half-life was 12.47 minutes. Renal clearance was 0.00051 L/kgBW per minute, whereas the systemic clearance was 0.0138 L/kgBW per minute. Because the renal clearance was much less than the rat inulin clearance reported in literature, the presence of C12 passive back-diffusion was hypothesized.