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Halvor Holm - One of the best experts on this subject based on the ideXlab platform.
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characteristics of digestive processes in atlantic salmon salmo salar enzyme ph optima Chyme ph and enzyme activities
Aquaculture, 2015Co-Authors: Ashild Krogdahl, Anne Sundby, Halvor HolmAbstract:Abstract Symptoms indicating digestive malfunction have been observed in cultivated salmon over the last 10–15 years, at least partially as a consequence of use of new feed ingredients. The present knowledge on many aspects of digestive functions in fish is limited, in particular for Atlantic salmon. Strengthening is needed to understand the mechanisms underlying challenges to gastrointestinal health and to find means to prevent their development. The present paper supplies information regarding digestive enzyme optima and stability, Chyme pH and enzyme activities along the digestive tract of Atlantic salmon. The data presented includes new data from four studies on Atlantic salmon as well as a review of comparative literature from various other fish studies. The four experiments comprised salmon of different sizes, kept in salt or fresh water, and fed high fish meal diets with different protein to energy ratios (P/E). These studies showed an average pH in the stomach Chyme, i.e. across diets and experiments, of 4.8 (SD = 0.7), whereas the observed pH optimum for pepsin was 3.0. In the intestinal Chyme, pH increased throughout the intestine from a mean of 8.1 (SD = 0.23) in the proximal intestine to 8.4 in the mid intestine (SD = 0.27) and distal intestine (SD = 0.29). Total proteolytic activity of Chyme in the proximal intestine, measured as the sum of the work of all proteolytic enzymes on casein as substrate, showed its maximum at pH 8.8, i.e. clearly above prevailing Chyme pH. For the individual proteolytic enzymes, pH optimum varied from 7.10 for elastase 1 to 8.98 for trypsin. Chyme pH did not appear to be influenced by fish size, but was significantly higher in the fish raised in fresh water than in those raised in salt water. In the intestinal Chyme pH showed a significant negative regression on diet P/E. For the investigated pancreatic enzymes in the intestinal Chyme, the activity in the Chyme decreased from proximal to distal regions and faecal activities were very low compared to the activities in the proximal intestine. The activity profile for leucine aminopeptidase (LAP), however, trended to increase from mid to distal intestine. Chyme enzyme activities along the intestinal tract did not differ clearly between the experiments and no clear relationship between P/E on enzyme activities along the intestinal tract was observed. Remarkable in vitro stability was observed for the proteolytic enzyme activities.
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effects of graded levels of medium chain triglycerides and cysteine on growth digestive processes and nutrient utilization in sea water reared atlantic salmon salmo salar l under ad libitum feeding regime
Aquaculture Nutrition, 2003Co-Authors: Sigve Nordrum, J J Olli, C Rosjo, Halvor Holm, Ashild KrogdahlAbstract:Fifteen experimental diets with five levels of medium chain triglycerides (MCT) (0, 39, 78, 117 and 156 g kg−1) and three levels of cysteine supplementations (0.0, 2.5 and 5.0 g kg−1) were fed ad libitum to Atlantic salmon (mean weight at start 846 g) in sea water for 71 days. Nutrient digestibilities and protein retention improved significantly with increasing dietary MCT level following simple linear regression models. Positive effects were also observed on proteolytic enzyme activities in Chyme of the pyloric region with peak value around 117 g kg−1 MCT. However, strong inverse relationships were observed between MCT level and feed intake, growth, body lipid and energy retention, and these effects accelerated with increasing MCT level. Also Chyme dry matter decreased with increasing MCT level which also seemed to stimulate pancreatic and bile secretion. MCT did not significantly affect condition factor, dress out percentage, relative liver size or pH in gastrointestinal contents. The only significant effects of dietary cysteine supplementation were increased enzyme activities in Chyme of the pyloric region with peak values for the intermediate cysteine level. The results elucidate the importance of diet composition for digestive functions, production efficiency and composition quality.
Fiorenza Minervini - One of the best experts on this subject based on the ideXlab platform.
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dose dependent lipid peroxidation induction on ex vivo intestine tracts exposed to Chyme samples from fumonisins contaminated corn samples
Toxicology in Vitro, 2015Co-Authors: Antonella Garbetta, Lucantonio Debellis, A De Girolamo, Roberto Schena, Angelo Visconti, Fiorenza MinerviniAbstract:Fumonisins (FBs), Fusarium mycotoxins common food contaminant, are a potent inducer of oxidative stress and lipid peroxidation in intestinal cells. In order to verify this toxic effect in intestine tract, the aim was to assess lipid peroxidation (as malondialdehyde MDA increased levels) on intestine rat samples exposed to Chyme samples from in vitro digestion of FBs contaminated corn samples. Naturally (9.61±3.2 μg/gr), artificially (726±94 μg/gr) and spiked corn samples at EU permitted FBs levels were digested and added to luminal side of Ussing chamber for 120 min. Fumonisins-free corn sample was used as control. The MDA increase was observed just in 83% of intestine samples exposed at EU FBs levels and the digestion process seems to reduce this incidence (50% of samples). Malondialdehyde levels were FBs dose- and subject-related and ranged from 0.07±0.01 to 3.59±0.6 nmol/mg. Highest incidence and MDA % increment (I) were found when intestine tracts were exposed to Chymes from artificially corn sample. The induction of lipid peroxidation induced by FBs could be due to interactions between FBs and intestinal membranes, with consequent modifications in membrane permeability and oxygen diffusion-concentration, as suggested by other authors.
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influence on functional parameters of intestinal tract induced by short term exposure to fumonisins contaminated corn Chyme samples
Food and Chemical Toxicology, 2014Co-Authors: Fiorenza Minervini, Antonella Garbetta, Lucantonio Debellis, A De Girolamo, Roberto Schena, Piero Portincasa, Angelo ViscontiAbstract:The gut is a possible target toward mycotoxin fumonisins (FBs) exposure. The study aims to investigate the effects induced by FBs contaminated-corn Chyme samples on functional parameters of human and rat intestine by using Ussing chamber. Fumonisins-contaminated corn and processed corn samples were undergone to in vitro digestion process and then added to luminal side. A reduction (about 90%) of short circuit current (Isc μA/cm2) during exposure of human colon tissues to fumonisins-free corn Chyme samples was observed, probably related to increased Chyme osmolality. This hyperosmotic stress could drain water towards the luminal compartment, modifying Na+ and Cl− transports. The presence of FBs in corn Chyme samples, independently to their concentration, did not affect significantly the Isc, probably related to their interference towards epithelial Na+ transport, as assessed by using a specific inhibitor (Amiloride). The rat colon tract represents a more accessible model to study FBs toxicity showing a similar functional response to human. In the rat small intestine a significant reduction (about 15%) of Isc parameter during exposure to uncontaminated or FBs contaminated corn Chyme samples was observed; therefore such model was not suitable to assess the FBs toxicity, probably because the prevalent glucose and amino acids electrogenic absorption overwhelmed the FBs influence on ionic transport.
Angelo Visconti - One of the best experts on this subject based on the ideXlab platform.
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dose dependent lipid peroxidation induction on ex vivo intestine tracts exposed to Chyme samples from fumonisins contaminated corn samples
Toxicology in Vitro, 2015Co-Authors: Antonella Garbetta, Lucantonio Debellis, A De Girolamo, Roberto Schena, Angelo Visconti, Fiorenza MinerviniAbstract:Fumonisins (FBs), Fusarium mycotoxins common food contaminant, are a potent inducer of oxidative stress and lipid peroxidation in intestinal cells. In order to verify this toxic effect in intestine tract, the aim was to assess lipid peroxidation (as malondialdehyde MDA increased levels) on intestine rat samples exposed to Chyme samples from in vitro digestion of FBs contaminated corn samples. Naturally (9.61±3.2 μg/gr), artificially (726±94 μg/gr) and spiked corn samples at EU permitted FBs levels were digested and added to luminal side of Ussing chamber for 120 min. Fumonisins-free corn sample was used as control. The MDA increase was observed just in 83% of intestine samples exposed at EU FBs levels and the digestion process seems to reduce this incidence (50% of samples). Malondialdehyde levels were FBs dose- and subject-related and ranged from 0.07±0.01 to 3.59±0.6 nmol/mg. Highest incidence and MDA % increment (I) were found when intestine tracts were exposed to Chymes from artificially corn sample. The induction of lipid peroxidation induced by FBs could be due to interactions between FBs and intestinal membranes, with consequent modifications in membrane permeability and oxygen diffusion-concentration, as suggested by other authors.
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influence on functional parameters of intestinal tract induced by short term exposure to fumonisins contaminated corn Chyme samples
Food and Chemical Toxicology, 2014Co-Authors: Fiorenza Minervini, Antonella Garbetta, Lucantonio Debellis, A De Girolamo, Roberto Schena, Piero Portincasa, Angelo ViscontiAbstract:The gut is a possible target toward mycotoxin fumonisins (FBs) exposure. The study aims to investigate the effects induced by FBs contaminated-corn Chyme samples on functional parameters of human and rat intestine by using Ussing chamber. Fumonisins-contaminated corn and processed corn samples were undergone to in vitro digestion process and then added to luminal side. A reduction (about 90%) of short circuit current (Isc μA/cm2) during exposure of human colon tissues to fumonisins-free corn Chyme samples was observed, probably related to increased Chyme osmolality. This hyperosmotic stress could drain water towards the luminal compartment, modifying Na+ and Cl− transports. The presence of FBs in corn Chyme samples, independently to their concentration, did not affect significantly the Isc, probably related to their interference towards epithelial Na+ transport, as assessed by using a specific inhibitor (Amiloride). The rat colon tract represents a more accessible model to study FBs toxicity showing a similar functional response to human. In the rat small intestine a significant reduction (about 15%) of Isc parameter during exposure to uncontaminated or FBs contaminated corn Chyme samples was observed; therefore such model was not suitable to assess the FBs toxicity, probably because the prevalent glucose and amino acids electrogenic absorption overwhelmed the FBs influence on ionic transport.
Denis Picot - One of the best experts on this subject based on the ideXlab platform.
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Chyme reinfusion or enteroclysis in nutrition of patients with temporary double enterostomy or enterocutaneous fistula
Current Opinion in Clinical Nutrition and Metabolic Care, 2016Co-Authors: Ronan Thibault, Denis PicotAbstract:Purpose of review: Patients with double temporary enterostomy or enterocutaneous fistula may suffer from intestinal failure. Parenteral nutrition is the gold standard treatment until surgical re-establishment of intestinal continuity, but serious complications may arise. Chyme reinfusion or enteroclysis are indicated. Recent findings: Chyme reinfusion corrects the intestinal failure by restoring intestinal absorption, allowing parenteral nutrition weaning in 91% of patients. Chyme reinfusion contributes to improve nutritional status and reduce plasma liver test abnormalities. Chyme reinfusion is feasible at home without any serious complications in selected patients. Mechanisms underlying Chyme reinfusion effectiveness on intestinal function, such as restoration of ileal brake, are suggested but most remain to be demonstrated. When the downstream small bowel is exposed, enteroclysis of enteral nutrition or hydration could be helpful to reduce parenteral nutrition needs, or in case of insufficient food intake during Chyme reinfusion. Summary: Chyme reinfusion or enteroclysis are less expensive, well tolerated, and easy-to-use nutrition support techniques, which may allow reducing parenteral nutrition-related healthcare costs. The latter remains to be demonstrated in the setting of a prospective randomized controlled trial. This review may contribute to improve the awareness of intensivists, digestive surgeons, and gastroenterologists involved in intestinal failure management to spread the use of Chyme reinfusion or enteroclysis.
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enterostomies temporaires a haut debit et reinstillation du Chyme a domicile experience d un centre
Nutrition Clinique Et Metabolisme, 2013Co-Authors: Denis PicotAbstract:Resume L’interruption de l’intestin grele par une enterostomie double peut entrainer un syndrome de grele court de type 1 responsable d’une insuffisance intestinale severe qui necessite des apports parenteraux pour couvrir les besoins et compenser les pertes. La reinstillation du Chyme est une technique qui retablit la continuite fonctionnelle de l’intestin anatomiquement present grâce a une circulation extracorporelle du Chyme. Recueilli a sa sortie de la stomie afferente, le Chyme est reinjecte immediatement dans l’intestin efferent hors circuit, sans manipulation, grâce a une pompe specifique. Les patients se nourrissent alors de ce qu’ils mangent, n’ont plus de pertes hydro-electrolytiques et les apports parenteraux sont arretes en quelques jours. La reinstillation du Chyme est realisable a domicile avec des pompes portables specifiques, chez des patients volontaires qui recoivent une education therapeutique particuliere, en attendant le retablissement chirurgical de la continuite intestinale.
Antonella Garbetta - One of the best experts on this subject based on the ideXlab platform.
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dose dependent lipid peroxidation induction on ex vivo intestine tracts exposed to Chyme samples from fumonisins contaminated corn samples
Toxicology in Vitro, 2015Co-Authors: Antonella Garbetta, Lucantonio Debellis, A De Girolamo, Roberto Schena, Angelo Visconti, Fiorenza MinerviniAbstract:Fumonisins (FBs), Fusarium mycotoxins common food contaminant, are a potent inducer of oxidative stress and lipid peroxidation in intestinal cells. In order to verify this toxic effect in intestine tract, the aim was to assess lipid peroxidation (as malondialdehyde MDA increased levels) on intestine rat samples exposed to Chyme samples from in vitro digestion of FBs contaminated corn samples. Naturally (9.61±3.2 μg/gr), artificially (726±94 μg/gr) and spiked corn samples at EU permitted FBs levels were digested and added to luminal side of Ussing chamber for 120 min. Fumonisins-free corn sample was used as control. The MDA increase was observed just in 83% of intestine samples exposed at EU FBs levels and the digestion process seems to reduce this incidence (50% of samples). Malondialdehyde levels were FBs dose- and subject-related and ranged from 0.07±0.01 to 3.59±0.6 nmol/mg. Highest incidence and MDA % increment (I) were found when intestine tracts were exposed to Chymes from artificially corn sample. The induction of lipid peroxidation induced by FBs could be due to interactions between FBs and intestinal membranes, with consequent modifications in membrane permeability and oxygen diffusion-concentration, as suggested by other authors.
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influence on functional parameters of intestinal tract induced by short term exposure to fumonisins contaminated corn Chyme samples
Food and Chemical Toxicology, 2014Co-Authors: Fiorenza Minervini, Antonella Garbetta, Lucantonio Debellis, A De Girolamo, Roberto Schena, Piero Portincasa, Angelo ViscontiAbstract:The gut is a possible target toward mycotoxin fumonisins (FBs) exposure. The study aims to investigate the effects induced by FBs contaminated-corn Chyme samples on functional parameters of human and rat intestine by using Ussing chamber. Fumonisins-contaminated corn and processed corn samples were undergone to in vitro digestion process and then added to luminal side. A reduction (about 90%) of short circuit current (Isc μA/cm2) during exposure of human colon tissues to fumonisins-free corn Chyme samples was observed, probably related to increased Chyme osmolality. This hyperosmotic stress could drain water towards the luminal compartment, modifying Na+ and Cl− transports. The presence of FBs in corn Chyme samples, independently to their concentration, did not affect significantly the Isc, probably related to their interference towards epithelial Na+ transport, as assessed by using a specific inhibitor (Amiloride). The rat colon tract represents a more accessible model to study FBs toxicity showing a similar functional response to human. In the rat small intestine a significant reduction (about 15%) of Isc parameter during exposure to uncontaminated or FBs contaminated corn Chyme samples was observed; therefore such model was not suitable to assess the FBs toxicity, probably because the prevalent glucose and amino acids electrogenic absorption overwhelmed the FBs influence on ionic transport.