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Digestive Function (digestive + function)
Selected AbstractsThe effects of diet switching and mixing on digestion in seabirdsFUNCTIONAL ECOLOGY, Issue 2 2000G. M. Hilton Abstract 1.,Animals modulate digestive function in order to optimize digestion of their current diet. Two seabird species were used to test the idea that, as a result, changing and mixing diets might adversely affect digestive performance. 2.,When switched from an energy-dense fish diet (Sprat, Sprattus sprattus (L.)) to an energy-dilute diet (Whiting, Merlangius merlangus (L.)), Lesser Black-Backed Gulls, Larus fuscus L. had worse digestive performance than birds that were acclimated to Whiting, indicating a cost of diet switching. However, when switched from Whiting to Sprat, Lesser Black-Backed Gulls had better digestive performance than birds acclimated to the Sprat diet. 3.,When switched from a Whiting to a Sprat diet some Common Guillemots, Uria aalge (Pont.), developed diarrhoea, although after acclimation birds were able to digest Sprat normally. 4.,Common Guillemots, but not Lesser Black-Backed Gulls, showed a reduction in digestive efficiency when given both diets in a mixed meal. 5.,Common Guillemots appear to have a less flexible digestive system than Lesser Black-Backed Gulls. This difference in response of the two species may be related to differences in their ecology. 6.,Subtle diet shifts may affect digestive performance of animals, and therefore digestive effects, as well as factors such as prey availability and ease of capture, might affect food choice. [source] Gastric emptying rate in subjects with experimentally shortened dental arches: a pilot studyJOURNAL OF ORAL REHABILITATION, Issue 6 2008Y. HATTORI Summary, Although a shortened dental arch has been reported to provide sufficient subjective chewing ability, the loss of molar occlusion significantly reduces trituration ability, and may result in an impaired digestive function including delayed gastric emptying. This study investigated the effect of the experimental loss of molar occlusion on gastric emptying rate. Thirteen healthy dentate males underwent two sessions of gastric emptying rate measurement after ingestion of the same test meal that contained ham, bread and an egg mixed with carbon-labelled octanoic acid. A test food was divided into nine equal portions, and each was consumed in 60 cycles of chewing. In one of the two sessions, the subjects wore an intraoral appliance devised to simulate the occlusal conditions of the shortened dental arches. Two parameters of gastric emptying; namely, the lag phase (Tlag) and gastric half-emptying time (T1/2), were evaluated by means of a 13C-octanoic acid breath test. Following the measurement of gastric emptying in each session, masticatory performance was evaluated by a conventional sieve test. Masticatory performance decreased significantly in case of loss of molar occlusion (78·1 ± 11·1% versus 33·4 ± 18·2%, P <0·001); however, no significant changes were observed in terms of the gastric emptying parameters (Tlag: 99 ± 19 versus 105 ± 34 min; T1/2: 168 ± 32 versus 178 ± 48 min). Within the limitations of this study, it was concluded that reduction in food trituration caused by shortening of the dental arch does not significantly affect gastrointestinal digestive function. [source] Recombinant expression and characterization of a lysozyme from the midgut of Triatoma brasiliensis (Hemiptera, Reduviidae) in comparison with intestinal muramidase activityPHYSIOLOGICAL ENTOMOLOGY, Issue 4 2009PETER J. WANIEK Abstract. Insect c-type lysozymes are antibacterial proteins that are synthesized in different organs with high activity against Gram-positive bacteria. Because lysozymes possess muramidase activity, they also play an important role in the digestion of bacteria in Diptera. Triatomines express lysozyme-encoding genes constitutively in the anterior region (cardia and stomach) of the midgut and the fat body after injection of bacteria into the haemocoel. The present study describes the overexpression of the Triatoma brasiliensis lysozyme 1 (lys1) in Escherichia coli. Recombinant T. brasiliensis Lys1 (TbLys1) is purified after solubilization of the inclusion bodies. The protein refolds successfully, showing muramidase activity against Micrococcus lysodeikticus lyophilized cells, after enterokinase cleavage of its thioredoxin fusion protein. In in-gel zymograms and turbidimetric liquid assays TbLys1 is broadly active under alkaline and acid conditions, indicating a possible digestive function in the two physiologically different midgut regions of the bug: the stomach and small intestine. Muramidase activity is shown in the stomach and small intestine content of unfed bugs and bugs at different days after feeding, respectively. Western blot analysis identifies TbLys1 as lysozyme. [source] Association of Extraesophageal Reflux Disease and Sinonasal Symptoms: Prevalence and Impact on Quality of Life,THE LARYNGOSCOPE, Issue 12 2007Thomas R. Pasic MD Abstract Objectives: The purpose of this study was to investigate the prevalence of extraesophageal reflux disease symptoms and their association with sinonasal disorders within a general sample of adults in our community and to determine how these conditions affect perception of general health, sinus-related quality of life (QOL), and perception of reflux and digestive function. Study Design/Methods: A community-dwelling sample of 1,878 adults completed symptom and QOL surveys in a two-stage prospective design: an initial screening questionnaire (n = 1,878) and disease-specific (sinus and reflux/digestion) and general health-related QOL instruments (n = 1,073). Demographic and response data were summarized and analyzed for prevalence and correlations among data sets. Results: Sinonasal symptoms were reported in 71% of subjects who completed the initial screening questionnaire, and reflux-related symptoms were reported by 59% of respondents. The co-occurrence of sinonasal and reflux symptoms was reported by 45% of respondents. Subjects with both sinonasal and reflux symptoms scored significantly worse on the disease-specific and general physical and mental QOL scales than subjects with only reflux or sinonasal symptoms or no symptoms. Conclusions: Symptoms associated with inflammatory sinonasal disorders and gastroesophageal reflux disease are common in the general U.S. adult population and co-occur in the same individuals to a greater degree than can be attributed to chance alone. Co-occurrence was found to be associated with significant declines in both disease-specific and general physical and mental QOL. This finding has implications with regard to pathogenesis and treatment of these disorders. [source] PANCREATICODUODENECTOMY WITH PANCREATICOGASTROSTOMY: ASSESSMENT OF PATIENTS' NUTRITIONAL STATUS, QUALITY OF LIFE AND PANCREATIC EXOCRINE FUNCTIONANZ JOURNAL OF SURGERY, Issue 3 2000Hock Soo Ong Background: The changes in digestive function of patients with pancreaticoduodenectomy (PD) and pancreaticogastrostomy reconstruction have not been well-documented. The present study sought to assess the nutritional status, quality of life and pancreatic exocrine function in this group of patients. Methods: The study group consisted of 11 PD with pancreaticogastrostomy patients. The control group consisted of 11 consecutive patients who had subtotal gastrectomy (SG) for distal stomach tumours. Results: The median ages for the PD and SG groups were 57 and 59 years, respectively. The median intervals between surgery to assessment were 68 and 60 weeks, respectively. The PD group attained a mean of 92.7% of their pre-surgery weight compared to 91.3% in the SG group. Both groups had a comparable gastrointestinal quality of life index and Visick scale scores. Exocrine insufficiency using the faecal chymotrypsin test was present in 36% of patients with PD. None of the patients in the SG group had exocrine insufficiency. Conclusion: Pancreaticoduodenectomy patients had a significant occurrence of pancreatic exocrine insufficiency compared to the SG group. But patients with PD and pancreaticogastrostomy reconstruction maintained a nutritional status and quality of life similar to those with curative SG for stomach malignancy. Apart from exocrine insufficiency, the concomitant gastrectomy in the PD group is an important factor responsible for their inability to gain weight. [source] Live feeds for early stages of fish rearingAQUACULTURE RESEARCH, Issue 5 2010Luís E C Conceição Abstract Despite the recent progress in the production of inert diets for fish larvae, feeding of most species of interest for aquaculture still relies on live feeds during the early life stages. Independently of their nutritional value, live feeds are easily detected and captured, due to their swimming movements in the water column, and highly digestible, given their lower nutrient concentration (water content>80%). The present paper reviews the main types of live feeds used in aquaculture, their advantages and pitfalls, with a special emphasis on their nutritional value and the extent to which this can be manipulated. The most commonly used live feeds in aquaculture are rotifers (Brachionus sp.) and brine shrimp (Artemia sp.), due to the existence of standardized cost-effective protocols for their mass production. However, both rotifers and Artemia have nutritional deficiencies for marine species, particularly in essential n-3 highly unsaturated fatty acids (HUFA, e.g., docosahexaenoic acid and eicosapentaenoic acid). Enrichment of these live feeds with HUFA-rich lipid emulsions may lead to an excess dietary lipid and sub-optimal dietary protein content for fish larvae. In addition, rotifers and Artemia are likely to have sub-optimal dietary levels of some amino acids, vitamins and minerals, at least for some species. Several species of microalgae are also used in larviculture. These are used as feed for other live feeds, but mostly in the ,green water' technique in fish larval rearing, with putative beneficial effects on feeding behaviour, digestive function, nutritional value, water quality and microflora. Copepods and other natural zooplankton organisms have also been used as live feeds, normally with considerably better results in terms of larval survival rates, growth and quality, when compared with rotifers and Artemia. Nonetheless, technical difficulties in mass-producing these organisms are still a constraint to their routine use. Improvements in inert microdiets will likely lead to a progressive substitution of live feeds. However, complete substitution is probably years away for most species, at least for the first days of feeding. [source] Factors affecting proliferation and differentiation of lepidopteran midgut stem cells,ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 1 2010Marcia J. Loeb Midgut stem cells of last instar larvae and pupae of Heliothis virescens, Lymantria dispar and several other Lepidopteran species have been cultured in vitro and have been induced to proliferate using low titers of ecdysteroids and the 77-Kda peptide fragment, ,-arylphorin, isolated and identified from pupal fat body tissue. The insulin-related hormone, Bombyxin, also induced mitosis in cultured midgut stem cells; it appeared to be fast-acting and quickly inactivated, while ,-arylphorin was slower to act and had a longer lasting effect in vitro, indicating different functions for these proliferation agents. Changes in Calcium ion concentration within or outside the cells discretely affected stem cell differentiation, indicating a role for second messenger participation in peptide regulation of this process. Four different peptides (MDFs 1,4) that induced midgut stem cells to differentiate to mature midgut cell types in vitro were isolated and characterized from conditioned media and hemolymph of H. virescens and L. dispar. However, platelet-derived growth factor (PDGF), epidermal growth factor (EGF), and all-trans retinoic acid (RA) from vertebrate sources induced differentiation to non-midgut cell types as well. MDF1 was located in basal areas of columnar cells of midgut epithelium, although MDF2 was observed in all of the cytoplasm of columnar cells and in droplets of antibody positive material in the midgut lumen, suggesting a digestive function as well for this peptide. Anti-MDF-3 stained the central areas of cultured midgut columnar cells and the bases of columnar cells of midgut epithelium in vivo. Midgut secretory cells stained with anti-MDF-4; streams of MFD-4-positive material were observed extending from secretory cells facing the epithelial lumen, and as a layer on the hemolymph-facing side, suggesting an endocrine or paracrine function for this or an immunologically similar peptide. Published 2010 Wiley Periodicals, Inc. [source] Alterations in the expression of intestinal enzymes in rats exposed to nickelJOURNAL OF APPLIED TOXICOLOGY, Issue 5 2006Amika Singla Abstract The effect of feeding nickel (50 mg kg,1 body weight) daily for 7 days was studied on the development of various brush border enzymes across the crypt,villus axis. The activities of brush border maltase (P < 0.05), lactase (P < 0.05), alkaline phosphatase (P < 0.05) and leucine amino peptidase (P < 0.05) were augmented in purified brush borders, whereas sucrase, trehlase (P < 0.01) and glutamyl transpeptidase (P < 0.05) were reduced in nickel fed animals compared with controls. Kinetic and heat inactivation studies with brush border sucrase and alkaline phosphatase confirmed these findings. Western blot analysis of alkaline phosphatase showed a strong signal for the enzyme protein but a reduced level of sucrase antigen in nickel fed rat intestine compared with the controls. These findings suggest that the expression of various brush border enzymes along the crypt,villus axis is modulated in rat intestine exposed to nickel, which may disrupt the digestive functions of the intestinal tissue. Copyright © 2006 John Wiley & Sons, Ltd. [source] Gross Morphology of the Intra-Oral rhamphotheca, Oropharynx and Proximal Oesophagus of the Emu (Dromaius novaehollandiae)ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2010M. R. Crole With 5 figures Summary Information on the gross morphology of the upper digestive tract of ratites is sparse. This is an important region considering that it is the first area for food selection and intake which is vital to the nutrition and growth of the animal and therefore its commercial viability. Twenty-three heads from sub-adult (12,14 months) emus were used to provide a definitive description of the oropharynx and proximal oesophagus. Besides supplying baseline morphological data of veterinary importance, this study also underlines the functional importance of this region. The mandibular and maxillary nails, and serrations on the rostral mandibular tomia, provide the emu with a formidable combination of gripping, tearing and pecking power. The folded oropharyngeal floor allows distention of the dorso-ventrally flattened cavity during eating and drinking. The laryngeal mound performs both respiratory and digestive functions, whereas the distensible proximal oesophagus supports the particular feeding method employed by ratites. [source] Influence of dietary phospholipids on early ontogenesis of fishAQUACULTURE RESEARCH, Issue 9 2009Chantal L Cahu Abstract The aim of this paper is to provide explanations of how dietary phospholipid (PL) globally improves fish larval development, including growth and survival, digestive functions and skeletal development, and to propose optimal PL levels and sources in fish larval diets. Dietary incorporation of 8,12% PL related to dry matter (d.m.) promotes growth and enhanced survival in various species. Marine source PL, incorporating highly unsaturated fatty acids, was most efficient than soybean lecithin. This beneficial effect was explained by an enhancement in digestive functions, assessed by digestive enzyme activities and histomorphology. Nevertheless, 1.5,2.5% highly unsaturated fatty acids related to diet d.m. supplied by PL improved growth, survival and skeletal development, while 5% induced different skeletal deformities. The high incidence of deformities was associated with the down-regulation of genes involved in development, such as RXR,, RAR,, RAR, and BMP-4, observed in the early stages in larvae fed a high highly unsaturated fatty acids level. [source] | ||||||||||||||||