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We have investigated the possible effects of algal polysaccharides on postprandial blood glucose and insulin responses in an animal model, the pig. Three seaweed fibres of different viscosities, extracted from Palmaria palmata (PP), Eucheuma cottonii (EC), or Laminaria digitata (LD), were compared to purified cellulose (CEL). Blood glucose and plasma insulin levels were monitored and intestinal absorption quantified for 8 h following a high carbohydrate test-meal supplemented with 5% fibre. Digestive contents were also sampled, 5 h postprandial. As compared to CEL, PP had no effect on glucose and insulin responses. The latter decreased with EC, but glucose absorption balance was not modified. LD addition resulted in a dramatically reduced glucose absorption balance, accompanied by a higher amount of starch left in the small intestine. Among polysaccharides tested, only the highly viscous alginates could affect intestinal absorption of glucose and insulin response.

Five Large White pigs of 62.2 ± 1.4 kg mean body weight were fitted with permanent catheters in the portal vein and carotid artery and with an electromagnetic flow probe around the portal vein to study the absorption of volatile fatty acids (VFA) by measuring the concentration of these metabolites in hourly blood samples, and by determining the portal blood flow rate for a period of 12 h after intake of a single 800-g meal (6% crude fiber) preceded by 12 or 24 h of fasting. The portal concentration of VFA mixture always highly exceeded the arterial concentration. The arterial concentrations of propionic, butyric, valeric and isovaleric acids were nearly null, accounting for an almost complete uptake of these VFA by the liver. Acetic acid also was taken up, but to a lesser extent. Total VFA absorption during 12 h was 64% higher (P<.05) after 12 h (1,160 ± 100 mmol/12 h) than after 24 h of preprandial fasting (740 ± 83 mmol/12 h). It increased after the meal (P<.05) from 82.3 ± 7.8 mmol/h between the first and fourth hour to 107.8 ± 7.5 mmol/h between the fifth and tenth hour when the preprandial fasting lasted 12 h; a nonsignificant increase also was found when fasting prior to the meal lasted 24 h. The composition of the VFA mixture was not modified by the length of preprandial fasting. With this type of diet there was a large predominance of acetic acid (52%) followed by propionic and butyric acids (36 and 8.5%, respectively). In feeding conditions of two meals per day, the absorption of VFA in a 60-kg pig represented about 30% of the energy requirements for maintenance. After a single 800-g meal, the 12-h absorption of VFA ranged from 400 to 450 mmol, i.e., 120 to 140 kcal.

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Four Large White pigs (mean body weight 62.8 ± 0.6 kg) were fitted with permanent catheters in the portal vein, carotid artery and duodenum, and with an electromagnetic flow probe around the portal vein. Eight days after surgery each animal received at 4-d intervals two duodenal infusions for 1 h each of solutions (1000 mL) containing 110 g of mild enzymic milk protein hydrolysate and 440 g of either a maltose-rich glucose syrup (54.6% maltose, 5.2% free glucose) or a maltitol-rich hydrogenated glucose syrup (54.2% maltitol, 6% free sorbitol). For 8 h after the beginning of each infusion, portal blood flow rate was recorded continuously, and blood samples were collected at various intervals (15 to 30 min) for the analysis of aminonitrogen, glucose and sorbitol. Maltitol was hydrolyzed substantially in the small gut. The absorption coefficient of glucose (percentage of infused glucose appearing in the portal blood) was the same 8 h after infusion of maltitol (78.1%) and maltose (78.8%). Sorbitol was poorly absorbed, with an absorption coefficient of 7.2% after 8 h. Its presence in the gut lumen did not inhibit the absorption of glucose. Aminonitrogen from milk oligopeptides appeared more rapidly in the portal vein during the first 4 h after infusion of maltitol than after that of maltose. This was probably due to a reduced competition between absorption of glucose and oligopeptides because of the smaller amount of glucose in the digestive lumen after maltitol hydrolysis.

L’utilisation du dispositif d’assistance ventriculaire gauche (DAVG) est en expansion chez les patients en insuffisance cardiaque avancée. Cependant, les infections liées au dispositif sont un défi à reconnaître et à traiter en raison d’un taux de morbidité et de mortalité important. Le rôle de l’imagerie de médecine nucléaire n’est pas encore bien établi pour les infections de DAVG. La présente étude compare les performances diagnostiques de la tomographie par émission de positons/tomodensitométrie au 18F-fluorodéoxyglucose (TEP-TDM au 18F-FDG) et de la scintigraphie aux leucocytes marqués (SLM) pour le diagnostic d’infections chez des patients porteurs d’un DAVG à flux continu.