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Sample records for aero digestive tract

  1. Association between OGG1 Ser326Cys polymorphism and risk of upper aero-digestive tract and gastrointestinal cancers: a meta-analysis.

    PubMed

    Das, Sambuddha; Nath, Sayantan; Bhowmik, Aditi; Ghosh, Sankar Kumar; Choudhury, Yashmin

    2016-01-01

    Cancers of the upper aero-digestive and gastrointestinal tract are one of the major causes of mortality around the world. DNA repair genes play a vital role in preventing carcinogenesis by maintaining genomic integrity. Polymorphisms in the nucleotide sequence of DNA repair genes are often reported to be associated with an increased risk for different cancers. The OGG1 gene encodes the enzyme 8-oxoguanine DNA glycosylase which removes oxidatively damaged bases of DNA. Several studies report that the OGG1 Ser326Cys polymorphism increases the risk for cancers of the upper aero-digestive and gastrointestinal tract. However, other studies provide evidence that such an association does not exist. A meta-analysis to assess the role of OGG1 Ser326Cys polymorphism in the cancers of the upper aero-digestive and gastrointestinal tract was therefore undertaken in order to resolve this ambiguity. Seventeen studies were recruited for this meta-analysis after screening 58 articles with a total of 5533 cases and 6834 controls for which the odds ratio with 95 % confidence interval was calculated. Begg's funnel test and Egger's test were performed for calculating publication bias. Our study reveals an association between OGG1 Ser326Cys polymorphism and cancer susceptibility of the upper aero-digestive and gastrointestinal tract (CG + GG vs CC; odds ratio, OR 1.22; 95 % CI 1.05-1.41; GG vs CG + CC; OR 1.36; 95 % CI 1.09-1.70; GG vs CC; OR 1.46; 95 % CI 1.12-1.92). Subgroup analysis based on cancer types and ethnicity also revealed the association of OGG1 Ser326Cys polymorphism to the risk for upper aero-digestive and gastrointestinal tract cancers among both the Asian and the Caucasian populations. No risk was however observed for smoking habits and OGG1 Ser326Cys polymorphism. In conclusion, OGG1 Ser326Cys polymorphism may be associated with the increased risk for aero-digestive tract and gastro-intestinal cancers in both Asian and Caucasian populations. PMID:27026921

  2. Hyaluronic Acid: Perspectives in Upper Aero-Digestive Tract. A Systematic Review

    PubMed Central

    Casale, Manuele; Moffa, Antonio; Sabatino, Lorenzo; Pace, Annalisa; Oliveto, Giuseppe; Vitali, Massimiliano; Baptista, Peter; Salvinelli, Fabrizio

    2015-01-01

    Background To date, topical therapies guarantee a better delivery of high concentrations of pharmacologic agents to the mucosa of the upper aerodigestive tract (UADT). The use of topical drugs, which are able to reduce mucosal inflammation and to improve healing tissues, can represent a relevant therapeutic advance. Topical sodium hyaluronate (SH) has recently been recognized as adjuvant treatment in the chronic inflammatory disease of the UADT. Aims The aim of our work was to review the published literature regarding all the potential therapeutic effects of SH in the chronic inflammatory disease of UADT. Methods Relevant published studies were searched in Pubmed, Google Scholar, Ovid using keywords (“sodium hyaluronate” and “upper airways”) or Medical Subject Headings. Results At the end of our selection process, sixteen publications have been included. Six of them in the post-operative period of nasal-sinus surgery, 2 of them in pediatric patients affected by recurrent upper respiratory tract infections, 4 of them in reducing symptoms and preventing exacerbations of chronic upper airways in adult population, 4 of them in patients with chronic inflammatory disease of UADT, including gastro-esophageal reflux disease (GERD). Conclusions Topical administration of SH plays a pivotkey role in the postoperative phase of patients undergoing FESS and nasal surgery, and positive results are generally observed in all the patients suffering from UADT chronic inflammatory disease. PMID:26120837

  3. Meat and heme iron intake and risk of squamous cell carcinoma of the upper aero-digestive tract in the European Prospective Investigation into Cancer and Nutrition (EPIC)

    PubMed Central

    Steffen, Annika; Bergmann, Manuela M.; Sánchez, María-José; Chirlaque, Maria-Dolores; Jakszyn, Paula; Amiano, Pilar; Quirós, J. Ramón; Gurrea, Aurelio Barricarte; Ferrari, Pietro; Romieu, Isabelle; Fedirko, Veronika; Bueno-de-Mesquita, H. B(as).; Siersema, Peter D.; Peeters, Petra HM; Khaw, Kay-Tee; Wareham, Nick; Allen, Naomi E.; Crowe, Francesca L.; Skeie, Guri; Hallmanns, Göran; Johansson, Ingegerd; Borgquist, Signe; Ericson, Ulrika; Egeberg, Rikke; Tjønneland, Anne; Overvad, Kim; Grote, Verena; Li, Kuanrong; Trichopoulou, Antonia; Oikonomidou, Despoina; Pantzalis, Menelaos; Tumino, Rosario; Panico, Salvatore; Palli, Domenico; Krogh, Vittorio; Naccarati, Alessio; Mouw, Traci; Vergnaud, Anne-Claire; Norat, Teresa; Boeing, Heiner

    2012-01-01

    Background Evidence from prospective studies on intake of meat and fish and risk of squamous cell carcinoma (SCC) of the upper aero-digestive tract (UADT) is scarce. We prospectively investigated the association of meat and fish intake with risk of SCC of the UADT and the possible mechanism via heme iron in the large multi-center European Prospective Investigation into Cancer and Nutrition (EPIC) study. Methods Multivariable proportional hazards models were used to estimate relative risks of SCC of the UADT in relation to intake of total meat, as well as subtypes of meat, fish and heme iron among 348,738 individuals from 7 European countries. Results During an average follow-up of 11.8 years, a total of 682 incident cases of UADT SCC were accrued. Intake of processed meat was positively associated with risk of SCC of the UADT in the total cohort (highest versus lowest quintile: RR=1.41; 95% CI=1.03-1.94), however, in stratified analyses, this association was confined to the group of current smokers (highest versus lowest quintile: RR=1.89; 95% CI=1.22-2.93). Red meat, poultry, fish and heme iron were not consistently related to UADT SCC. Conclusion Higher intake of processed meat was positively associated with SCC of the UADT among smokers. Although this finding was stable in various sensitivity analyses, we cannot rule out residual confounding by smoking. Confirmation in future studies and identification of biological mechanisms is warranted. Impact Smokers may further increase their risk for SCC of the UADT if they additionally consume large amounts of processed meat. PMID:23033453

  4. Gas in the Digestive Tract

    MedlinePlus

    ... digestive tract when you swallow air and when bacteria in your large intestine break down certain undigested foods. ​​​​ Diagnosis of Gas Doctors may diagnose the causes of gas with a medical history and physical exam. If your doctor suspects you ...

  5. Digestive tract morphology and digestion in the wombats (Marsupialia: Vombatidae).

    PubMed

    Barboza, P S; Hume, I D

    1992-01-01

    Wombats consume grasses and sedges which are often highly fibrous. The morphology of the digestive tract and the sequence of digestion were studied in two species of wombats from contrasting habitats: Vombatus ursinus from mesic habitats and Lasiorhinus latifrons from xeric regions. Studies were performed on wild wombats consuming their natural winter diets, and on captive wombats fed a high-fibre pelleted straw diet. Vombatus had a shorter digestive tract (9.2 vs 12.5 times body length) of greater capacity (wet contents 17.9 vs 13.7% body weight) than Lasiorhinus. The most capacious region of the digestive tract was the proximal colon (62-79% of contents). The proportional length and surface area of the proximal colon were greater in Vombatus, but those of the distal colon were greater in Lasiorhinus. These digestive morphologies may reflect adaptations for greater capacity and longer retention of digesta in Vombatus, but greater absorption and lower faecal water loss in Lasiorhinus. Apparent digestion along the digestive tract was estimated by reference to lignin. The proximal colon was the principal site of fibre and dry matter digestion, whereas nitrogen was mainly digested in the small intestine. Depot fats in captive wombats were highly unsaturated and reflected those in the diet. Therefore, lipids, proteins and soluble carbohydrates in the plant cell contents were digested and absorbed in the stomach and small intestine. Conversely, dietary fibre was probably retained and digested by microbial fermentation along the proximal colon. PMID:1430423

  6. Digestive tract morphology and digestion in the wombats (Marsupialia: Vombatidae).

    PubMed

    Barboza, P S; Hume, I D

    1992-01-01

    Wombats consume grasses and sedges which are often highly fibrous. The morphology of the digestive tract and the sequence of digestion were studied in two species of wombats from contrasting habitats: Vombatus ursinus from mesic habitats and Lasiorhinus latifrons from xeric regions. Studies were performed on wild wombats consuming their natural winter diets, and on captive wombats fed a high-fibre pelleted straw diet. Vombatus had a shorter digestive tract (9.2 vs 12.5 times body length) of greater capacity (wet contents 17.9 vs 13.7% body weight) than Lasiorhinus. The most capacious region of the digestive tract was the proximal colon (62-79% of contents). The proportional length and surface area of the proximal colon were greater in Vombatus, but those of the distal colon were greater in Lasiorhinus. These digestive morphologies may reflect adaptations for greater capacity and longer retention of digesta in Vombatus, but greater absorption and lower faecal water loss in Lasiorhinus. Apparent digestion along the digestive tract was estimated by reference to lignin. The proximal colon was the principal site of fibre and dry matter digestion, whereas nitrogen was mainly digested in the small intestine. Depot fats in captive wombats were highly unsaturated and reflected those in the diet. Therefore, lipids, proteins and soluble carbohydrates in the plant cell contents were digested and absorbed in the stomach and small intestine. Conversely, dietary fibre was probably retained and digested by microbial fermentation along the proximal colon.

  7. [Physiology of microflora in the digestive tract].

    PubMed

    Zboril, V

    2002-01-01

    The microflora of the digestive tract is a complex microbial ecosystem, well balanced, which in an aboral direction undergoes specific changes as to the ratio of aerobic and anaerobic microorganisms the functions of which supplement each other--the aerobes ensure for the whole ecosystem the scavenger effect. The microbial profile of the digestive tract is typical by the absence of anaerobic microorganisms in the stomach and conversely their absolute predominance in the distal colon. The basic physiological functions of the microflora of the digestive tract can be characterized as follows: 1. microbial barrier against pathogens and potential pathogens, 2. formation of products of the microflora and their influence on the blood supply of the intestinal mucosa and peristaltics, 3. stimulation of the immune system in the gut, 4. reduction of bacterial translocation, 5. production of vitamins. To this problem in the world literature, contrary to ours, deserved attention has been paid for many years. Knowledge of the problem opens the door to expedient manipulation with the microbial flora of the digestive tract by the use of diet or prebiotics, probiotics as well as antibiotic treatment. The author presents a summary of basic findings which developed on the subject of physiological microflora of the digestive tract successively up to their present shape.

  8. Bifidobacteria in the digestive tract of bumblebees.

    PubMed

    Killer, Jirí; Kopecný, Jan; Mrázek, Jakub; Rada, Vojtech; Dubná, Sona; Marounek, Milan

    2010-04-01

    Bifidobacteria and other bacterial groups (lactobacilli, facultative anaerobes, anaerobes) from the digestive tract of three bumblebee species (Bombus lucorum (34 samples), Bombus pascuorum (18 samples) and Bombus lapidarius (9 samples)) were enumerated and characterised. Counts of facultative anaerobic bacteria and lactobacilli (5.41+/-2.92 and 2.69+/-3.02 log CFU/g of digestive tract content) were lower than those of anaerobes (7.66+/-0.86 log CFU/g). Counts of bifidobacteria were determined using two selective media: MTPY (Modified Trypticase Phytone Yeast extract agar) and a new medium with pollen extract. There was no significant difference between the counts of bifidobacteria from both media, 5.00+/-2.92 log CFU/g on MTPY and 5.00+/-2.87 on the pollen medium. Subsequently, 187 bacterial strains of the family Bifidobacteriaceae (fructose-6-phosphate phosphoketolase-positive) were isolated from three different localities and from all three species of bumblebees. Bifidobacteria were found in 42 out of 61 specimens (69%). Twenty-three (38%) specimens had counts of bifidobacteria higher than 7.0 log CFU/g. Bifidobacteria represented the dominant group of anaerobes (>70% of total anaerobes), i.e., the principal group of bacteria in the bumblebee digestive tract, in only fourteen specimens (23% of total). For the first time, bifidobacteria were isolated from the digestive tract of bumblebees. In addition, we suggest, on the basis of biochemical tests (API 50 CHL and RAPID ID 32) and genetic methods (PCR and DGGE), that these bacteria may represent new species within the family of Bifidobacteriaceae.

  9. Nitrogen partitioning along the equine digestive tract.

    PubMed

    Glade, M J

    1983-10-01

    Twelve adult horses were fed a corn-oats-timothy hay diet containing 2.87% nitrogen (N) for 4 wk and were then killed. Fresh digesta samples were immediately harvested from the stomach, duodenum, jejunum, ileum, cecum, large colon, small colon, rectum and feces. Total N content of the digesta (on a dry matter basis) increased from the stomach (2.74%) to the duodenum (5.58%; P less than .01), decreased in the cecum (3.10%, P less than .01), remained constant through the large intestine and decreased in the feces (2.10%; P less than .01). High-speed centrifugation of wet digesta and low-speed centrifugation following tungstic acid treatment of wet digesta were comparable in their effectiveness in separating water soluble N-containing compounds (S-N) from insoluble N-containing compounds (P-N). The P-N was further partitioned into neutral detergent soluble (NDS-N) and neutral detergent insoluble (NDF-N) fractions. The NDF-N constituted from 6 to 17% of the total digesta N at any location along the digestive tract. The S-N constituted about 20% of the total digesta N in the stomach, increased to about 80% at mid-jejunum (P less than .01), decreased to 30% in the cecum (P less than .01) and increased throughout the large intestine. The calculation of cumulative apparent digestibilities indicated that total digesta N underwent net disappearance along the entire tract, except in the duodenum. Dietary NDF-N underwent net disappearance throughout the digestive tract. The NDS-N portion of the P-N disappeared in the duodenum, jejunum and small colon, but underwent net appearance in the ileum, cecum and large colon. There was a net appearance of S-N in the duodenum and net disappearances in the ileum and cecum. The shifts in N partitioning along the lower digestive tract and the decreases in N concentrations suggest that the jejunum, ileum, cecum and small colon are major sites of the net absorption of N and that much of the N absorbed in the small colon was supplied by the

  10. CONSIDERATIONS ON ANATOMY AND PHYSIOLOGY OF LYMPH VESSELS OF UPPER AERO DIGESTIVE ORGANS AND CERVICAL SATELLITE LYMPH NODE GROUP.

    PubMed

    Ciupilan, Corina; Stan, C I

    2016-01-01

    The almost constant local regional development of the cancers of upper aero digestive organs requires the same special attention to cervical lymph node metastases, as well as to the primary neoplastic burning point. The surgical therapy alone or associated has a mutilating, damaging character, resulting in loss of an organ and function, most of the times with social implications, involving physical distortions with aesthetic consequences, which make the reintegration of the individual into society questionable. The problem of cervical lymph node metastases is vast and complex, reason why we approached several anatomical and physiological aspects of lymph vessels of the aero digestive organs. Among the available elements during treatment, the headquarters of the tumour, its histologic degree, and its infiltrative nature, each of them significantly influences the possibility of developing metastases.

  11. CONSIDERATIONS ON ANATOMY AND PHYSIOLOGY OF LYMPH VESSELS OF UPPER AERO DIGESTIVE ORGANS AND CERVICAL SATELLITE LYMPH NODE GROUP.

    PubMed

    Ciupilan, Corina; Stan, C I

    2016-01-01

    The almost constant local regional development of the cancers of upper aero digestive organs requires the same special attention to cervical lymph node metastases, as well as to the primary neoplastic burning point. The surgical therapy alone or associated has a mutilating, damaging character, resulting in loss of an organ and function, most of the times with social implications, involving physical distortions with aesthetic consequences, which make the reintegration of the individual into society questionable. The problem of cervical lymph node metastases is vast and complex, reason why we approached several anatomical and physiological aspects of lymph vessels of the aero digestive organs. Among the available elements during treatment, the headquarters of the tumour, its histologic degree, and its infiltrative nature, each of them significantly influences the possibility of developing metastases. PMID:27483727

  12. A Proteomic Analysis of the Body Wall, Digestive Tract, and Reproductive Tract of Brugia malayi.

    PubMed

    Morris, C Paul; Bennuru, Sasisekhar; Kropp, Laura E; Zweben, Jesse A; Meng, Zhaojing; Taylor, Rebekah T; Chan, King; Veenstra, Timothy D; Nutman, Thomas B; Mitre, Edward

    2015-01-01

    Filarial worms are parasitic nematodes that cause devastating diseases such as lymphatic filariasis (LF) and onchocerciasis. Filariae are nematodes with complex anatomy including fully developed digestive tracts and reproductive organs. To better understand the basic biology of filarial parasites and to provide insights into drug targets and vaccine design, we conducted a proteomic analysis of different anatomic fractions of Brugia malayi, a causative agent of LF. Approximately 500 adult female B. malayi worms were dissected, and three anatomical fractions (body wall, digestive tract, and reproductive tract) were obtained. Proteins from each anatomical fraction were extracted, desalted, trypsinized, and analyzed by microcapillary reverse-phase liquid chromatography-tandem-mass spectrometry. In total, we identified 4,785 B. malayi proteins. While 1,894 were identified in all three anatomic fractions, 396 were positively identified only within the digestive tract, 114 only within the body wall, and 1,011 only within the reproductive tract. Gene set enrichment analysis revealed a bias for transporters to be present within the digestive tract, suggesting that the intestine of adult filariae is functional and important for nutrient uptake or waste removal. As expected, the body wall exhibited increased frequencies of cytoskeletal proteins, and the reproductive tract had increased frequencies of proteins involved in nuclear regulation and transcription. In assessing for possible vaccine candidates, we focused on proteins sequestered within the digestive tract, as these could possibly represent "hidden antigens" with low risk of prior allergic sensitization. We identified 106 proteins that are enriched in the digestive tract and are predicted to localize to the surface of cells in the the digestive tract. It is possible that some of these proteins are on the luminal surface and may be accessible by antibodies ingested by the worm. A subset of 27 of these proteins appear

  13. Comparative Screening of Digestion Tract Toxic Genes in Proteus mirabilis

    PubMed Central

    Shi, Xiaolu; Lin, Yiman; Qiu, Yaqun; Li, Yinghui; Jiang, Min; Chen, Qiongcheng; Jiang, Yixiang; Yuan, Jianhui; Cao, Hong; Hu, Qinghua; Huang, Shenghe

    2016-01-01

    Proteus mirabilis is a common urinary tract pathogen, and may induce various inflammation symptoms. Its notorious ability to resist multiple antibiotics and to form urinary tract stones makes its treatment a long and painful process, which is further challenged by the frequent horizontal gene transferring events in P. mirabilis genomes. Three strains of P. mirabilis C02011/C04010/C04013 were isolated from a local outbreak of a food poisoning event in Shenzhen, China. Our hypothesis is that new genes may have been acquired horizontally to exert the digestion tract infection and toxicity. The functional characterization of these three genomes shows that each of them independently acquired dozens of virulent genes horizontally from the other microbial genomes. The representative strain C02011 induces the symptoms of both vomit and diarrhea, and has recently acquired a complete type IV secretion system and digestion tract toxic genes from the other bacteria. PMID:27010388

  14. Traditional serrated adenomas of the upper digestive tract.

    PubMed

    Rubio, C A

    2016-01-01

    For many years, it was generally accepted that the vast majority of the colorectal carcinomas (CRCs) evolved from conventional adenomas, via the adenoma-carcinoma sequence. More recently, serrated colorectal polyps (hyperplastic polyps, sessile serrated polyps and traditional serrated adenomas (TSAs)) have emerged as an alternative pathway of colorectal carcinogenesis. It has been estimated that about 30% of the CRC progress via the serrated pathway. Recently, TSAs were also detected in the upper digestive tract. In this work, we review the literature on TSA in the oesophagus, the stomach, the duodenum, the pancreatic main duct and the gallbladder. The review indicated that 53.4% (n=39) out of the 73 TSA of the upper digestive tract now in record showed a simultaneously growing invasive carcinoma. As a corollary, TSAs of the upper digestive tract are aggressive adenomas that should be radically excised, either endoscopically or surgically, to rule out the possibility of a synchronously growing invasive adenocarcinoma or to prevent cancer progression. The present findings substantiate a TSA pathway of carcinogenesis in the upper digestive tract. PMID:26468393

  15. A Proteomic Analysis of the Body Wall, Digestive Tract, and Reproductive Tract of Brugia malayi

    PubMed Central

    Morris, C. Paul; Bennuru, Sasisekhar; Kropp, Laura E.; Zweben, Jesse A.; Meng, Zhaojing; Taylor, Rebekah T.; Chan, King; Veenstra, Timothy D.; Nutman, Thomas B.; Mitre, Edward

    2015-01-01

    Filarial worms are parasitic nematodes that cause devastating diseases such as lymphatic filariasis (LF) and onchocerciasis. Filariae are nematodes with complex anatomy including fully developed digestive tracts and reproductive organs. To better understand the basic biology of filarial parasites and to provide insights into drug targets and vaccine design, we conducted a proteomic analysis of different anatomic fractions of Brugia malayi, a causative agent of LF. Approximately 500 adult female B. malayi worms were dissected, and three anatomical fractions (body wall, digestive tract, and reproductive tract) were obtained. Proteins from each anatomical fraction were extracted, desalted, trypsinized, and analyzed by microcapillary reverse-phase liquid chromatography-tandem-mass spectrometry. In total, we identified 4,785 B. malayi proteins. While 1,894 were identified in all three anatomic fractions, 396 were positively identified only within the digestive tract, 114 only within the body wall, and 1,011 only within the reproductive tract. Gene set enrichment analysis revealed a bias for transporters to be present within the digestive tract, suggesting that the intestine of adult filariae is functional and important for nutrient uptake or waste removal. As expected, the body wall exhibited increased frequencies of cytoskeletal proteins, and the reproductive tract had increased frequencies of proteins involved in nuclear regulation and transcription. In assessing for possible vaccine candidates, we focused on proteins sequestered within the digestive tract, as these could possibly represent “hidden antigens” with low risk of prior allergic sensitization. We identified 106 proteins that are enriched in the digestive tract and are predicted to localize to the surface of cells in the the digestive tract. It is possible that some of these proteins are on the luminal surface and may be accessible by antibodies ingested by the worm. A subset of 27 of these proteins

  16. Pythiosis of the digestive tract in sheep.

    PubMed

    Pessoa, Clarice R M; Riet-Correa, Franklin; Pimentel, Luciano A; Garino, Felício; Dantas, Antônio F M; Kommers, Glaucia D; Tabosa, Ivon M; Reis-Júnior, Janildo L

    2012-11-01

    Cutaneous and rhinofacial infections by Pythium insidiosum have previously been reported in sheep in Brazil. In the current study, a new form of pythiosis involving the alimentary tract of 2 nursing lambs from 2 different farms in the semiarid region of Brazil is described. The first lamb showed food regurgitation, lethargy, and anorexia, and died 5 days after the presentation of clinical signs. The second lamb had no history of gastrointestinal disease before death. Necropsy findings were similar in both lambs. The mucosa of the esophagus, reticulum, rumen, omasum, and abomasum showed ulcerated areas covered by yellowish caseous granular exudate. The lesions were transmural and extended to the serosal surfaces, and adhesions were observed between the serosa of the forestomachs and abomasum to the liver and diaphragm. Histologic lesions consisted of pyogranulomatous necrotizing transmural esophagitis, rumenitis, reticulitis, omasitis, and abomasitis with vascular thrombosis and intralesional hyphae. Pythium insidiosum was confirmed as the etiology by immunohistochemistry and culture. The presence of sheep in the vicinity of water ponds during the hot, dry season when forage is not available in the pastures seems to be the main predisposing factor for the occurrence of pythiosis in sheep in the Brazilian semiarid region. PMID:23051827

  17. Digestion of hay protein in different segments of the equine digestive tract.

    PubMed

    Gibbs, P G; Potter, G D; Schelling, G T; Kreider, J L; Boyd, C L

    1988-02-01

    Mature ponies fitted with permanent ileal cannulas were used in a 3 X 3 Latin square experiment to quantify prececal, postileal and total tract digestion of hay protein. Coastal Bermuda grass (CB), containing 11.7% crude protein, and two qualities of alfalfa, containing 15.0% (low-protein alfalfa; LA) and 18.1% (high-protein alfalfa; HA) crude protein, were fed in coarsely chopped form at 2% of body weight daily. Total tract apparent digestibility of the N in HA (73.8%) was higher than that in CB (57.0%; P less than .05) and was slightly higher than that in LA (66.1%; P less than .10). Nitrogen in LA was apparently more digestible than that in CB (P less than .05). Apparent prececal digestibilities of N in LA and CB were 1.3% and 9.6%, respectively, and were lower (P less than .05), or tended to be lower (P less than .10), than the 21.0% observed for HA. In relative terms, an average of 9.4% of the total N digestion occurred in the upper tract when CB and LA were fed, whereas 28.5% of total N digestion occurred in the foregut when HA was fed. There was a slightly higher concentration of total plasma free amino acids (P less than .10) at 1 h postfeeding when horses were fed alfalfa. Also, N retention was higher when ponies were fed HA (P less than .05) than when LA or CB were fed. Apparent postileal N digestibility was 52.5% for CB, 65.7% for LA and 66.9% for HA. Differences were not significant, and the large intestine appeared to compensate for the inefficiency of N digestion in the upper tract.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Gastroesophageal reflux disease and non-digestive tract diseases.

    PubMed

    Chen, Ying

    2015-05-01

    Over the past decade, incidence of gastroesophageal reflux disease (GERD) showed an increasing trend resulting from factors, including lifestyle and dietary habits; however, both etiology and pathological mechanisms remain controversial. GERD occurs as a result of a variety of mechanisms and there is no single factor. Symptoms of GERD are often non-typical, with a likelihood of being overlooked by non-gastroenterology professionals. Therefore, improving GERD awareness in non-gastroenterology practitioners, along with early diagnosis and treatment, provide potential benefit to clinicians and patients alike. Increasing evidence suggests GERD has specific connections with a variety of non-digestive tract conditions, may contribute an aggravating compounding effect on other diseases, prolong hospitalization, and increase subsequent medical costs. This review considers and emphasizes the association between GERD and non-digestive tract conditions, including atrial fibrillation, chronic obstructive pulmonary disease, primary pulmonary fibrosis and energy metabolism related to diet.

  19. Lessons from Digestive-Tract Symbioses Between Bacteria and Invertebrates.

    PubMed

    Graf, Joerg

    2016-09-01

    In most animals, digestive tracts harbor the greatest number of bacteria in the animal that contribute to its health: by aiding in the digestion of nutrients, provisioning essential nutrients and protecting against colonization by pathogens. Invertebrates have been used to enhance our understanding of metabolic processes and microbe-host interactions owing to experimental advantages. This review describes how advances in DNA sequencing technologies have dramatically altered how researchers investigate microbe-host interactions, including 16S rRNA gene surveys, metagenome experiments, and metatranscriptome studies. Advantages and challenges of each of these approaches are described herein. Hypotheses generated through omics studies can be directly tested using site-directed mutagenesis, and findings from transposon studies and site-directed experiments are presented. Finally, unique structural aspects of invertebrate digestive tracts that contribute to symbiont specificity are presented. The combination of omics approaches with genetics and microscopy allows researchers to move beyond correlations to identify conserved mechanisms of microbe-host interactions. PMID:27482740

  20. In vivo digestion of bovine milk fat globules: effect of processing and interfacial structural changes. II. Upper digestive tract digestion.

    PubMed

    Gallier, Sophie; Zhu, Xiang Q; Rutherfurd, Shane M; Ye, Aiqian; Moughan, Paul J; Singh, Harjinder

    2013-12-01

    The aim of this research was to study the effect of milk processing on the in vivo upper digestive tract digestion of milk fat globules. Fasted rats were serially gavaged over a 5h period with cream from raw, pasteurised, or pasteurised and homogenised milk. Only a few intact dietary proteins and peptides were present in the small intestinal digesta. Significantly (P<0.05) more longer chain (C≥10) fatty acids were present in the digesta of rats gavaged with raw (448 mg g(-1) digesta dry matter (DDM)) and homogenised creams (528 mg g(-1) DDM), as compared to pasteurised and homogenised cream (249 mg g(-1) DDM). Microscopy techniques were used to investigate the structural changes during digestion. Liquid-crystalline lamellar phases surrounding the fat globules, fatty acid soap crystals and lipid-mucin interactions were evident in all small intestinal digesta. Overall, the pasteurised and homogenised cream appeared to be digested to a greater extent. PMID:23871080

  1. The Paramagnetic Pillared Bentonites as Digestive Tract MRI Contrast Agents

    NASA Astrophysics Data System (ADS)

    Mojović, Miloš; Daković, Marko; Omerašević, Mia; Mojović, Zorica; Banković, Predrag; Milutinović-Nikolić, Aleksandra; Jovanović, Dušan

    The increased use of imaging techniques in diagnostic studies, such as MRI, has contributed to the development of the wide range of new materials which could be successfully used as image improving agents. However, there is a lack of such substances in the area of gastrointestinal tract MRI. Many of the traditionally popular relaxation altering agents show poor results and disadvantages provoking black bowel, side effects of diarrhea and the presence of artifacts arising from clumping. Paramagnetic species seem to be potentially suitable agents for these studies, but contrast opacification has been reported and less than 60% of the gastrointestinal tract magnetic resonance scans showed improved delineation of abdominal pathologies. The new solution has been proposed as zeolites or smectite clays (hectorite and montmorillonite) enclosing of paramagnetic metal ions obtained by ion-exchange methods. However, such materials have problems of leakage of paramagnetic ions causing the appearance of the various side-effects. In this study we show that Co+2 and Dy+3 paramagnetic-pillared bentonites could be successfully used as MRI digestive tract non-leaching contrast agents, altering the longitudinal and transverse relaxation times of fluids in contact with the clay minerals.

  2. Quantitative Macroscopic Anatomy of the Giraffe (Giraffa camelopardalis) Digestive Tract.

    PubMed

    Sauer, C; Bertelsen, M F; Lund, P; Weisbjerg, M R; Clauss, M

    2016-10-01

    Quantitative data on digestive anatomy of the world's largest ruminant, the giraffe, are scarce. Data were collected from a total of 25 wild-caught and 13 zoo-housed giraffes. Anatomical measures were quantified by dimension, area or weight and analysed by allometric regression. The majority of measures scaled positively and isometrically to body mass. Giraffes had lower tissue weight of all stomach compartments and longer large intestinal length than cattle. When compared to other ruminants, the giraffe digestive tract showed many of the convergent morphological adaptations attributed to browsing ruminants, for example lower reticular crests, thinner ruminal pillars and smaller surface area of the omasal laminae. Salivary gland weight of the giraffe, however, resembled that of grazing ruminants. This matches a previous finding of similarly small salivary glands in the other extant giraffid, the okapi (Okapia johnstoni), suggesting that not all convergent characteristics need be expressed in all species and that morphological variation between species is a combination of phylogenetic and adaptational signals.

  3. Quantitative Macroscopic Anatomy of the Giraffe (Giraffa camelopardalis) Digestive Tract.

    PubMed

    Sauer, C; Bertelsen, M F; Lund, P; Weisbjerg, M R; Clauss, M

    2016-10-01

    Quantitative data on digestive anatomy of the world's largest ruminant, the giraffe, are scarce. Data were collected from a total of 25 wild-caught and 13 zoo-housed giraffes. Anatomical measures were quantified by dimension, area or weight and analysed by allometric regression. The majority of measures scaled positively and isometrically to body mass. Giraffes had lower tissue weight of all stomach compartments and longer large intestinal length than cattle. When compared to other ruminants, the giraffe digestive tract showed many of the convergent morphological adaptations attributed to browsing ruminants, for example lower reticular crests, thinner ruminal pillars and smaller surface area of the omasal laminae. Salivary gland weight of the giraffe, however, resembled that of grazing ruminants. This matches a previous finding of similarly small salivary glands in the other extant giraffid, the okapi (Okapia johnstoni), suggesting that not all convergent characteristics need be expressed in all species and that morphological variation between species is a combination of phylogenetic and adaptational signals. PMID:27593556

  4. [The yeast community associated with the digestive tract of the German cockroach Blattella germanica L].

    PubMed

    Zheltikova, T M; Glushakova, A M; Alesho, N A

    2011-01-01

    Data on the yeasts colonizing the digestive tract ofa German cockroach have been first obtained. Cockroach cultures are used in the commercial production of allergy vaccines to treat patients sensitized to cockroach allergens. The enteric microflora of the insects can bring nonshared antigens into the composition of the agents manufactured. An investigation established that out of 10 yeast species isolated from the digestive tract of the cockroaches fed sterile food, 6 species (Candida glabrata, Cryptococcus magnus, Debaryomyces hansenii, Metschikowia pulcherrima, Phodo-torula glutinis, Rhodotorula mucilaginosa) were isolated from both the digestive tract and excrements and 4 (Candida oleophila, Candida shehatae, Cryptococcus albidus, Pichia membmnaefciens) were only from the digestive tract. It seems that the yeast is either digested or inactivated in the digestive tract of the insects and loses their capacity to grow When the cockroaches were fed sterile food for a long time (at least a month), all yeasts virtually disappeared from the digestive tract of the insects except for Candida glabrata, C.shehatae, and Rh.mucilaginosa. However, only C.glabrata achieved a great deal (10(7)-10(8) CFU/g) of cockroaches (both imagoes and larvae of 5-7 ages), which statistically significantly decreased by no less than three orders of magnitude in the excrements after passing through the digestive tract.

  5. Persistence of identifiable remains of white sturgeon juveniles in digestive tracts of northern pikeminnow

    USGS Publications Warehouse

    Gadomski, D.M.; Frost, C.N.

    2004-01-01

    Juvenile white sturgeon, Acipenser transmontanus, have not been commonly identified as prey items in digestive tracts of fishes collected in the wild. In particular, the diet of northern pikeminnow, Ptychocheilus oregonensis, an abundant Pacific Northwest freshwater predator which has been widely studied, has not included juvenile white sturgeon. To aid in interpreting these results and help in planning future feeding studies, we determined the persistence of identifiable remains of white sturgeon juveniles in this predator's digestive tract. Northern pikeminnow (mean total length = 476 mm), were force-fed meals of 2 or 3 juvenile white sturgeon (mean total length = 91 mm). After digestive periods of 4, 8, 16, 24, 28, and 32h at a water temperature of about 17 ??C, fish were sacrificed, digestive tracts removed, and contents examined. Our results indicate that juvenile white sturgeon would be readily discernable in digestive tracts of northern pikeminnow at least a day after feeding, with scutes remaining undigested and identifiable for 28 h.

  6. Digestive tract ontogeny of Dicentrarchus labrax: implication in osmoregulation.

    PubMed

    Giffard-Mena, Ivone; Charmantier, Guy; Grousset, Evelyse; Aujoulat, Fabien; Castille, René

    2006-04-01

    The ontogeny of the digestive tract (DT) and of Na(+)/K(+)-ATPase localization was investigated during the early postembryonic development (from yolk sac larva to juvenile) of the euryhaline teleost Dicentrarchus labrax reared at two salinities: seawater and diluted seawater. Histology, electron microscopy and immunocytochemistry were used to determine the presence and differentiation of ion transporting cells. At hatching, the DT is an undifferentiated straight tube over the yolk sac. At the mouth opening (day 5), it comprises six segments: buccopharynx, esophagus, stomach, anterior intestine, posterior intestine and rectum, well differentiated at the juvenile stage (day 72). The enterocytes displayed ultrastructural features similar to those of mitochondria-rich cells known to be involved in active ion transport. At hatching, ion transporting cells lining the intestine and the rectum exhibited a Na(+)/K(+)-ATPase activity which increased mainly after the larva/juvenile (20 mm) metamorphic transition. The immunofluorescence intensity was dependent upon the stage of development of the gut as well as on the histological configuration of the analyzed segment. The appearance and distribution of enteric ionocytes and the implication of the DT in osmoregulation are discussed.

  7. Digestive tract evacuation in northern squawfish (Ptychocheilus oregonensis)

    USGS Publications Warehouse

    Beyer, J.M.; Lucchetti, G.; Gray, G.

    1988-01-01

    Digestive tract evacuation in northern squawfish (Ptychocheilus oregonensis) (170–1900 g) was studied in fish allowed to feed voluntarily on salmon (4–70 g) at three water temperatures (10, 15, and 20 °C). Squawfish were sacrificed at 1- or 2-h intervals until evacuation approximated 90%. Amount of food evacuated for a given time interval increased approximately three times as the temperature was increased and as the prey weight was increased and two times as the predator weight was increased. The 90% emptying time (ET90) decreased by about two thirds as the temperature doubled and by about one half as the predator weight increased 10 times, but approximately doubled when the prey weight increased 4 times. Two-fish meals (17–20 g each, 35–39 g total) were evacuated more slowly than meals of one fish weighing 17–20 g, but at the same rate as meals of one fish weighing 35–40 g. Equations derived are easily applied to a wide range of water temperatures, prey weights, and predator weights.

  8. [Involvement of human papillomavirus in upper aero-digestive tracts cancers].

    PubMed

    Neufcoeur, P Ernoux; Arafa, M; Delvenne, P; Saussez, S

    2009-10-01

    Human papillomavirus (HPV) is one of the most common causes of sexually transmitted infection in the world. France and Belgium present one of the highest incidence of head and neck squamous cell carcinomas (HNSCC) worldwide. Besides, considering only the male population, HNSCCs represent the fourth most frequent cancer after prostate, lung and colon cancers. Although the causal link between high-risk HPVs and cervical carcinoma is well established, the implication of this viral infection in HNSCC remains debatable. Here, we discuss current knowledge concerning the HPV implication in HNSCCs. Based on our literature review, 20 to 25% of HNSCCs could be associated with oncogenic HPVs, in particular HPV type 16. The oropharynx--more precisely the tonsil--is the head and neck location presenting the highest incidence of HPV infection. Moreover, a clear increase of tonsillar carcinoma incidence has been described. As observed in cervical carcinomas, HPV positive HNSCCs are sexually transmitted and characterized by alterations of p53 and pRb signalling pathways. Several studies have shown that HPV positive subgroup presented better prognosis particularly if these patients overexpressed p16INK4. New studies regarding HPV status in HNSCCs are warranted to provide a rationale for large scale HPV vaccination in young male populations.

  9. GM crops and the rat digestive tract: a critical review.

    PubMed

    Zdziarski, I M; Edwards, J W; Carman, J A; Haynes, J I

    2014-12-01

    The aim of this review is to examine the relationship between genetically modified (GM) crops and health, based on histopathological investigations of the digestive tract in rats. We reviewed published long-term feeding studies of crops containing one or more of three specific traits: herbicide tolerance via the EPSPS gene and insect resistance via cry1Ab or cry3Bb1 genes. These genes are commonly found in commercialised GM crops. Our search found 21 studies for nine (19%) out of the 47 crops approved for human and/or animal consumption. We could find no studies on the other 38 (81%) approved crops. Fourteen out of the 21 studies (67%) were general health assessments of the GM crop on rat health. Most of these studies (76%) were performed after the crop had been approved for human and/or animal consumption, with half of these being published at least nine years after approval. Our review also discovered an inconsistency in methodology and a lack of defined criteria for outcomes that would be considered toxicologically or pathologically significant. In addition, there was a lack of transparency in the methods and results, which made comparisons between the studies difficult. The evidence reviewed here demonstrates an incomplete picture regarding the toxicity (and safety) of GM products consumed by humans and animals. Therefore, each GM product should be assessed on merit, with appropriate studies performed to indicate the level of safety associated with them. Detailed guidelines should be developed which will allow for the generation of comparable and reproducible studies. This will establish a foundation for evidence-based guidelines, to better determine if GM food is safe for human and animal consumption.

  10. Determinants of hypofibrinolysis in patients with digestive tract cancer

    PubMed Central

    Gronostaj, Katarzyna; Richter, Piotr; Nowak, Wojciech

    2016-01-01

    Introduction Recently, we demonstrated that digestive tract cancer (DTC) is associated with reduced fibrin clot permeability and impaired fibrinolysis. Aim We investigated determinants of fibrinolysis in DTC patients. Material and methods In 44 consecutive patients with DTC and 47 controls matched for age, sex, and cardiovascular risk, we evaluated fibrinolysis proteins, platelet activation markers, thrombin formation, together with plasma clot lysis time assays in the absence (CLT) and presence of carboxypeptidase potato inhibitor (CLT CPI) that blocks thrombin activatable fibrinolysis inhibitor (TAFI). Results In the DTC group CLT (by 22.3%) and CLT CPI (by 27.4%) were longer compared with controls. The DTC patients had higher plasma fibrinolysis inhibitors, plasminogen activator inhibitor 1 (PAI-1) (by 18.2%), TAFI activity (by 17.3%), and antigen (by 11.2%). The patients had markedly increased platelet markers – soluble CD40 ligand (by 338%) and P-selectin (by 97%), together with von Willebrand factor (vWF) antigen (by 61%). Thrombin-antithrombin complexes (TAT) (by 48.7%) and soluble thrombomodulin (sTM) (by 17.2%) were also increased in the DTC group (all p < 0.05). Patients with high-grade tumours (n = 26) compared with remainders (n = 18) had longer CLT, higher tissue-type plasminogen activator antigen, both TAFI antigen and activity levels, vWF, and sTM. Multiple regression analysis after adjustment for potential confounders showed that independent predictors of CLT in DTC patients were TAT, TAFI activity, and vWF. The only independent predictor of CLT CPI was TAT. Conclusions Hypofibrinolysis in DTC patients is largely driven by enhanced thrombin generation, TAFI, and endothelial injury. PMID:27350837

  11. Morphological and histological changes in digestive tract development during starvation in the miiuy croaker.

    PubMed

    Shan, Xiujuan; Quan, Hanfeng; Dou, Shuozeng

    2016-04-01

    A histological method was used to describe the ontogenetic development of the digestive tract of laboratory-reared miiuy croaker (Miichthys miiuy) and to evaluate the effects of short-term food deprivation on the morphology and histology of the digestive tract. Larvae and juveniles were maintained at 24 °C in a thermostatically controlled system. Three starvation experiments were conducted during different developmental stages: 1-7 days after hatching (dah; prior to benthic swimming); 26-35 dah (during settling); and 42-53 dah (after benthic swimming). According to the structural changes in the ontogenetic development of the digestive tract, three stages were observed. The first stage was from hatching to 3 dah; the digestive tract was undifferentiated in newly hatched larvae and then showed remarkable morphological changes and differentiation. During this period, larvae depended on endogenous nutrition. The second stage (4-20 dah) was a critical period in which larvae transitioned from endogenous feeding to exogenous feeding and the digestive tract fully differentiated into the buccopharynx, oesophagus, stomach, anterior intestine and posterior intestine. Goblet cells and vacuoles appeared in the digestive tract, and pharyngeal teeth and taste buds developed. During the third stage (20-36 dah), the gastric glands developed and the stomach differentiated into the fundic, cardiac and pyloric regions. At 25 dah, pyloric caeca developed and mucosal folds and spiral valves were clearly distinguishable. After 30 dah, the digestive tract did not undergo any noticeable differentiation, indicating the complete development of the digestive system. The wet weight and SGR (specific growth rate) of miiuy croaker larvae and juveniles greatly decreased when they were deprived of food, and compensatory growth was observed in re-feeding juveniles. The livers of starved larvae and juveniles were atrophied and dark coloured, the intestines were transparent and thin, and the stomach

  12. Ontogeny of the digestive tract in sharpsnout sea bream Diplodus puntazzo (Cetti, 1777).

    PubMed

    Micale, V; Di Giancamillo, A; Domeneghini, C; Mylonas, C C; Nomikos, N; Papadakis, I E; Muglia, U

    2008-09-01

    The ontogeny of the digestive tract was studied histologically and histochemically in sharpsnout sea bream Diplodus puntazzo from hatching (0 DAH, Days After Hatching) until day 57 (57 DAH). At hatching, the digestive tract appeared as a histologically undifferentiated straight tube lying dorsally to the yolk sac. When the mouth opened at 3 DAH, the digestive tract was differentiated into buccopharynx, oesophagus, incipient stomach and intestine. The pancreas, liver and gall bladder were also differentiated at this stage and both the bile and pancreatic duct had opened into the anterior intestine. Active feeding began in 50% of larvae at 4 DAH, although permanence of yolk reserves until 7 DAH suggests a period of both endogenous and exogenous feeding. Nutrient absorption was first visible from 5 DAH, as colourless supra- and infranuclear vacuoles in the anterior intestinal mucosa, suggesting a lipid content, as well as supranuclear, eosinophilic vacuoles, containing protein, in the posterior intestinal mucosa. Early caecal development could be detected from 10 DAH, whereas gastric glands appeared at 30 DAH, indicating the transition from larval to juvenile stage and the acquisition of an adult mode of digestion. Goblet cells appeared in the digestive tract of sharpsnout sea bream larvae shortly after first feeding. The mucus content of goblet cells varied with the digestive region and, in the buccal cavity and oesophagus, also with the developmental phase. This study provides knowledge for better husbandry practices in the aquaculture industry, as well as for the implementation of future nutritional studies.

  13. Ontogeny of the digestive tract in sharpsnout sea bream Diplodus puntazzo (Cetti, 1777).

    PubMed

    Micale, V; Di Giancamillo, A; Domeneghini, C; Mylonas, C C; Nomikos, N; Papadakis, I E; Muglia, U

    2008-09-01

    The ontogeny of the digestive tract was studied histologically and histochemically in sharpsnout sea bream Diplodus puntazzo from hatching (0 DAH, Days After Hatching) until day 57 (57 DAH). At hatching, the digestive tract appeared as a histologically undifferentiated straight tube lying dorsally to the yolk sac. When the mouth opened at 3 DAH, the digestive tract was differentiated into buccopharynx, oesophagus, incipient stomach and intestine. The pancreas, liver and gall bladder were also differentiated at this stage and both the bile and pancreatic duct had opened into the anterior intestine. Active feeding began in 50% of larvae at 4 DAH, although permanence of yolk reserves until 7 DAH suggests a period of both endogenous and exogenous feeding. Nutrient absorption was first visible from 5 DAH, as colourless supra- and infranuclear vacuoles in the anterior intestinal mucosa, suggesting a lipid content, as well as supranuclear, eosinophilic vacuoles, containing protein, in the posterior intestinal mucosa. Early caecal development could be detected from 10 DAH, whereas gastric glands appeared at 30 DAH, indicating the transition from larval to juvenile stage and the acquisition of an adult mode of digestion. Goblet cells appeared in the digestive tract of sharpsnout sea bream larvae shortly after first feeding. The mucus content of goblet cells varied with the digestive region and, in the buccal cavity and oesophagus, also with the developmental phase. This study provides knowledge for better husbandry practices in the aquaculture industry, as well as for the implementation of future nutritional studies. PMID:18581279

  14. Digestive-tract sarcoidosis: French nationwide case-control study of 25 cases.

    PubMed

    Ghrenassia, Etienne; Mekinian, Arsene; Chapelon-Albric, Catherine; Levy, Pierre; Cosnes, Jacques; Sève, Pascal; Lefèvre, Guillaume; Dhôte, Robin; Launay, David; Prendki, Virginie; Morell-Dubois, Sandrine; Sadoun, Danielle; Mehdaoui, Anas; Soussan, Michael; Bourrier, Anne; Ricard, Laure; Benamouzig, Robert; Valeyre, Dominique; Fain, Olivier

    2016-07-01

    Digestive tract sarcoidosis (DTS) is rare and case-series are lacking. In this retrospective case-control study, we aimed to compare the characteristics, outcome, and treatment of patients with DTS, nondigestive tract sarcoidosis (NDTS), and Crohn disease.We included cases of confirmed sarcoidosis, symptomatic digestive tract involvement, and noncaseating granuloma in any digestive tract. Each case was compared with 2 controls with sarcoidoisis without digestive tract involvement and 4 with Crohn disease.We compared 25 cases of DTS to 50 controls with NDTS and 100 controls with Crohn disease. The major digestive clinical features were abdominal pain (56%), weight loss (52%), nausea/vomiting (48%), diarrhea (32%), and digestive bleeding (28%). On endoscopy of DTS, macroscopic lesions were observed in the esophagus (9%), stomach (78%), duodenum (9%), colon, (25%) and rectum (19%). As compared with NDTS, DTS was associated with weight loss (odds ratio [OR] 5.8; 95% confidence interval [CI] 1.44-23.3) and the absence of thoracic adenopathy (OR 5.0; 95% CI 1.03-25). As compared with Crohn disease, DTS was associated with Afro-Caribbean origin (OR 27; 95% CI 3.6-204) and the absence of ileum or colon macroscopic lesions (OR 62.5; 95% CI 10.3-500). On the last follow-up, patients with DTS showed no need for surgery (versus 31% for patients with Crohn disease; P = 0.0013), and clinical digestive remission was frequent (76% vs. 35% for patients with Crohn disease; P = 0.0002).The differential diagnosis with Crohn disease could be an issue with DTS. Nevertheless, the 2 diseases often have different clinical presentation and outcome. PMID:27442665

  15. Application of ultrasound technology in the diagnosis and treatment of digestive tract diseases.

    PubMed

    Fu, W-X; Wang, Q; Zhang, Y-S; Li, Y; Xu, T; He, S; Ren, H; Sun, T

    2015-02-01

    Ultrasound is commonly used in clinical examination which is economic, non-invasive and convenient. Ultrasound can be used for the examination of solid organs and hollow organs. Due to the presence of air, routine ultrasound examination of the digestive tract is not very appropriate, Because of the development of endosonography and its related technology, diagnosis and treatment of gastrointestinal diseases have been improved which is valuable in clinic. This review focused on the application of ultrasound technology in the diagnosis and treatment of digestive tract diseases.

  16. Recovery of Soybean Cyst Nematodes (Heterodera glycines) from the Digestive Tracts of Blackbirds.

    PubMed

    Epps, J M

    1971-10-01

    Digestive tract contents and feces of blackbirds were examined for cysts of Heterodera glycines, the soybean cyst nematode. Birds fed under laboratory conditions and trapped in naturally-infested fields were checked. Infective larvae were recovered from cysts in the excrement of birds 24 and 48 hr after they were fed cysts. Birds that were force-fed eggs and larvae discharged infective larvae in the excrement. Birds which consumed cysts mixed with feed and cysts in feed mixed with soil discharged numerous cysts containing infective larvae. Seven of 54 starlings, trapped and killed in an infested field, contained cysts in their digestive tracts.

  17. New endoscopic ultrasound techniques for digestive tract diseases: A comprehensive review

    PubMed Central

    Meng, Fan-Sheng; Zhang, Zhao-Hong; Ji, Feng

    2015-01-01

    Endoscopic ultrasound (EUS) is one of the most important modalities for the diagnosis of digestive tract diseases. EUS has been evolving ever since it was introduced. New techniques such as elastography and contrast enhancement have emerged, increasing the accuracy, sensitivity and specificity of EUS for the diagnosis of digestive tract diseases including pancreatic masses and lymphadenopathy. EUS-elastography evaluates tissue elasticity and therefore, can be used to differentiate various lesions. Contrast-enhanced EUS can distinguish benign from malignant pancreatic lesions and lymphadenopathy using the intravenous injection of contrast agents. This review discusses the principles and types of these new techniques, as well as their clinical applications and limitations. PMID:25944994

  18. Complete Genome Sequence of Bifidobacterium actinocoloniiforme Type Strain DSM 22766T, Isolated from Bumblebee Digestive Tracts.

    PubMed

    Chen, Xiaohan; E, Zhiguo; Gu, Donglu; Lv, Longxian; Li, Yudong

    2015-01-01

    Bifidobacteria are one of the most important beneficial bacteria in the gut of mammals and insects. We sequenced the genome of B. actinocoloniiforme DSM 22766, which was isolated from the digestive tracts of bumblebees. The genome contains 1,548 protein-coding genes, 49 RNAs and two CRISPR repeats. PMID:26404606

  19. Associations among digestive tract lesions and abnormal serum chemistries in cull dairy cattle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All animals accrue tissue damage with age, but types and prevalence of damage are not known. Tissue lesions could signal impaired organ function which could affect performance. The study objective was to assess prevalence of microscopic lesions in digestive tracts of cull dairy cows, and determine a...

  20. Terreneuvian Orthothecid (Hyolitha) Digestive Tracts from Northern Montagne Noire, France; Taphonomic, Ontogenetic and Phylogenetic Implications

    PubMed Central

    Devaere, Léa; Clausen, Sébastien; Álvaro, J. Javier; Peel, John S.; Vachard, Daniel

    2014-01-01

    More than 285 specimens of Conotheca subcurvata with three-dimensionally preserved digestive tracts were recovered from the Terreneuvian (early Cambrian) Heraultia Limestone of the northern Montagne Noire, southern France. They represent one of the oldest occurrences of such preserved guts. The newly discovered operculum of some complete specimens provides additional data allowing emendation of the species diagnosis. Infestation of the U-shaped digestive tracts by smooth uniseriate, branching to anastomosing filaments along with isolated botryoidal coccoids attests to their early, microbially mediated phosphatisation. Apart from taphonomic deformation, C. subcurvata exhibits three different configurations of the digestive tract: (1) anal tube and gut parallel, straight to slightly undulating; (2) anal tube straight and loosely folded gut; and (3) anal tube straight and gut straight with local zigzag folds. The arrangement of the digestive tracts and its correlation with the mean apertural diameter of the specimens are interpreted as ontogenetically dependent. The simple U-shaped gut, usually considered as characteristic of the Hyolithida, developed in earlier stages of C. subcurvata, whereas the more complex orthothecid type-3 only appears in largest specimens. This growth pattern suggests a distinct phylogenetic relationship between these two hyolith orders through heterochronic processes. PMID:24533118

  1. Terreneuvian orthothecid (Hyolitha) digestive tracts from northern Montagne Noire, France; taphonomic, ontogenetic and phylogenetic implications.

    PubMed

    Devaere, Léa; Clausen, Sébastien; Alvaro, J Javier; Peel, John S; Vachard, Daniel

    2014-01-01

    More than 285 specimens of Conotheca subcurvata with three-dimensionally preserved digestive tracts were recovered from the Terreneuvian (early Cambrian) Heraultia Limestone of the northern Montagne Noire, southern France. They represent one of the oldest occurrences of such preserved guts. The newly discovered operculum of some complete specimens provides additional data allowing emendation of the species diagnosis. Infestation of the U-shaped digestive tracts by smooth uniseriate, branching to anastomosing filaments along with isolated botryoidal coccoids attests to their early, microbially mediated phosphatisation. Apart from taphonomic deformation, C. subcurvata exhibits three different configurations of the digestive tract: (1) anal tube and gut parallel, straight to slightly undulating; (2) anal tube straight and loosely folded gut; and (3) anal tube straight and gut straight with local zigzag folds. The arrangement of the digestive tracts and its correlation with the mean apertural diameter of the specimens are interpreted as ontogenetically dependent. The simple U-shaped gut, usually considered as characteristic of the Hyolithida, developed in earlier stages of C. subcurvata, whereas the more complex orthothecid type-3 only appears in largest specimens. This growth pattern suggests a distinct phylogenetic relationship between these two hyolith orders through heterochronic processes.

  2. Characterization of the digestive-tract microbiota of Hirudo orientalis, a european medicinal leech.

    PubMed

    Laufer, Alison S; Siddall, Mark E; Graf, Joerg

    2008-10-01

    FDA-approved, postoperative use of leeches can lead to bacterial infections. In this study, we used culture-dependent and culture-independent approaches to characterize the digestive-tract microbiota of Hirudo orientalis. Surprisingly, two Aeromonas species, A. veronii and A. jandaei, were cultured. Uncultured Rikenella-like bacteria were most similar to isolates from Hirudo verbana.

  3. Pathophysiology of cystic fibrosis and drugs used in associated digestive tract diseases

    PubMed Central

    Haack, Adriana; Aragão, Giselle Gonçalves; Novaes, Maria Rita Carvalho Garbi

    2013-01-01

    Cystic fibrosis (CF) causes chronic infections in the respiratory tract and alters the digestive tract. This paper reviews the most important aspects of drug treatment and changes in the digestive tract of patients with CF. This is a review of the literature, emphasizing the discoveries made within the last 15 years by analyzing scientific papers published in journals indexed in the Scientific Electronic Library Online, Sciences Information, United States National Library of Medicine and Medical Literature Analysis and Retrieval System Online databases, both in English and Portuguese, using the key words: cystic fibrosis, medication, therapeutic, absorption, digestion. Randomized, observational, experimental, and epidemiological clinical studies were selected, among others, with statistical significance of 5%. This review evaluates the changes found in the digestive tract of CF patients including pancreatic insufficiency, constipation and liver diseases. Changes in nutritional status are also described. Clinical treatment, nutritional supplementation and drug management were classified in this review as essential to the quality of life of CF patients, and became available through public policies for monitoring and treating CF. The information gathered on CF and a multi professional approach to the disease is essential in the treatment of these patients. PMID:24379572

  4. Wood degradation in the digestive tract of the Formosan subterranean termite (Isoptera: Rhinotermitidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most wood decomposition in the digestive tract of subterranean termite workers occurs in food vacuoles of flagellate protozoan symbionts in the hindgut. This study uses scanning electron microscopy to analyze the degree of degradation of wood particles in different regions of the termite gut. Gut co...

  5. A pilot study on respiratory and digestive tract cancer among woodworkers.

    PubMed

    Esping, B; Axelson, O

    1980-09-01

    Cancer of the nose and paranasal sinuses is a known occupational hazard among workers in the furniture industry. An increased frequency of cancer at other sites has also been suggested to occur among different types of woodworkers in the United States, eg, cancer of the gastrointestinal tract and lung but also lymphatic and hematopoietic malignancies. This case-referent study is of a pilot character and was undertaken for the further elucidation of respiratory and digestive tract cancer among Swedish woodworkers. A four-fold excess of respiratory cancer, other than nasal cancer, was found, particularly in relation to furniture workers, whereas no definite excess of digestive tract cancer was indicated. Further studies seem worthwhile regarding cancer hazard in the woodworking industry.

  6. Structure of the digestive tract of tornaria larva in Enteropneusta (Hemichordata)

    NASA Astrophysics Data System (ADS)

    Dautov, S. Sh.; Nezlin, L. P.; Yushin, V. V.

    1994-03-01

    The ultrastructure of the digestive tract of tornaria larva of enteropneusts was investigated. It showed that the digestive tract consists of three parts: esophagus, stomach, and intestine. The esophagus epithelium consists of two types of multiciliated epithelial cells and solitary muscle cells. Axonal tracts and neurons were found in the ventral wall of the esophagus. The cardiac sphincter contains an anterior band of strongly ciliated cells and a posterior band of cells with long vacuolized processes which partition the sphincter lumen. The stomach consists of three cell types: (1) cells with electron-opaque cytoplasm, bearing a fringed border on their apical sides; (2, 3) sparse cells with electron-light cytoplasm and different patterns of apical microvilli. Cells of the pyloric sphincter bear numerous cilia and almost no microvilli. The intestine consists of three parts. The anterior part is formed of multiciliated cells which bear the fringed border. The middle part consists of flattened cells bearing rare cilia and vast numbers of mace-like microvilli. The posterior part of the intestine is formed of cells bearing numerous cilia and few microvilli. Muscle cells were not found in either stomach or intestine epithelium. One noticed that the structure of the digestive tract of enteropneust tornaria larva differs from that of echinoid pluteus larva.

  7. A Rare Disease of the Digestive Tract: Esophageal Melanosis

    PubMed Central

    Destek, Sebahattin; Gul, Vahit Onur; Ahioglu, Serkan; Erbil, Yesim

    2016-01-01

    Esophageal melanosis which is characterized by melanocytic proliferation in the squamous epithelium of the esophagus and melanin accumulatin of esophageal mucosa (EM) is a rare disease of the digestive system. Although esophageal melanosis is considered to be a benign disease, its etiology is not cleared and has been reported to be the precursor lesion of esophageal primary melanomas. In this report, we aimed to note esophageal melanosis in a 55-year-old female case who applied to our clinic with difficulty in swallowing, burning behind the breastbone in the stomach, heartburn, indigestion, and pain in the upper abdomen after endoscopic and pathologic evaluation. Complaints dropped with anti-acid therapy and case was followed by intermittent endoscopic procedures because of precursor melanocytic lesions. PMID:27785326

  8. Meta-analysis of randomised controlled trials of selective decontamination of the digestive tract. Selective Decontamination of the Digestive Tract Trialists' Collaborative Group.

    PubMed Central

    1993-01-01

    OBJECTIVE--To determine the clinical benefits of selective decontamination of the digestive tract in patients treated in intensive care units. DESIGN--Meta-analysis of 22 randomised trials that compared different combinations of oral non-absorbable antibiotics, with or without a systemic component, with no treatment in controls. SUBJECTS--4142 patients seen in general and specialised intensive care units around the world. 2047 received some form of antibiotic treatment, the remainder no prophylaxis. DATA ANALYSIS--Each trial was reviewed through direct contact with study investigators. Data collected were: the randomisation procedure, number of patients, number excluded from the analysis, and numbers of respiratory tract infections and deaths. Data were combined according to an intention to treat analysis with the Mantel-Haenszel-Peto method. MAIN OUTCOME MEASURES--Respiratory tract infections and total mortality. RESULTS--Selective decontamination of the digestive tract significantly reduced respiratory tract infections (odds ratio 0.37; 95% confidence interval 0.31 to 0.43). The value of the common odds ratio for total mortality (0.90; 0.79 to 1.04) suggested at best a moderate treatment effect, reaching statistical significance only when the subgroup of trials of topical and systemic treatment combined was considered separately (odds ratio 0.80; 0.67 to 0.97). No firm conclusions could be drawn owing to large variations in patient mix and severity within and between trials. CONCLUSIONS--The findings strongly indicate that selective decontamination significantly reduces infection related morbidity in patients receiving intensive care. They also highlight why definite conclusions about the effect of prophylaxis on mortality cannot be drawn despite the large number of trials available. Based on the most favourable results obtained by pooling data from trials in which combined topical and systemic treatment was used it may be estimated that 6 (range 5-9) and 23 (13

  9. Phytate and phosphorus movements in the digestive tract of horses.

    PubMed

    Matsui, T; Murakami, Y; Yano, H; Fujikawa, H; Osawa, T; Asai, Y

    1999-07-01

    This experiment was conducted to study phytate degradation and the effect of dietary phytate level on phosphorus absorption in the gastrointestinal tract of horses. Six Thoroughbred horses were fed diets containing low-phytate diet or high-phytate diet for 5 days. The diets were supplemented with Cr2O3 as an unabsorbable marker. The horses were killed 3 h after the last feeding and digesta in some segments of the intestine were collected. In both dietary groups, the daily passage of phytate phosphorus was decreased in the upper small intestine and in the lower large intestine. The daily passage of phytate phosphorus in the lower large intestine did not differ between these groups. Although the passage of total phosphorus increased in the upper small intestine and in the upper large intestine of both groups, its passage decreased in the lower large intestine. These results suggest that phytate phosphorus is degraded in the upper small intestine and in the lower large intestine of both groups. Phosphorus is suggested to be mainly absorbed in the lower large intestine. Therefore, phytate phosphorus is considered to be easily absorbed in horses because the major site of phosphorus is the lower large intestine where most of phytate is already degraded.

  10. Hydrogen Sulfide in Physiology and Diseases of the Digestive Tract

    PubMed Central

    Singh, Sudha B.; Lin, Henry C.

    2015-01-01

    Hydrogen sulfide (H2S) is a Janus-faced molecule. On one hand, several toxic functions have been attributed to H2S and exposure to high levels of this gas is extremely hazardous to health. On the other hand, H2S delivery based clinical therapies are being developed to combat inflammation, visceral pain, oxidative stress related tissue injury, thrombosis and cancer. Since its discovery, H2S has been found to have pleiotropic effects on physiology and health. H2S is a gasotransmitter that exerts its effect on different systems, such as gastrointestinal, neuronal, cardiovascular, respiratory, renal, and hepatic systems. In the gastrointestinal tract, in addition to H2S production by mammalian cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE), H2S is also generated by the metabolic activity of resident gut microbes, mainly by colonic Sulfate-Reducing Bacteria (SRB) via a dissimilatory sulfate reduction (DSR) pathway. In the gut, H2S regulates functions such as inflammation, ischemia/ reperfusion injury and motility. H2S derived from gut microbes has been found to be associated with gastrointestinal disorders such as ulcerative colitis, Crohn’s disease and irritable bowel syndrome. This underscores the importance of gut microbes and their production of H2S on host physiology and pathophysiology.

  11. Hydrogen Sulfide in Physiology and Diseases of the Digestive Tract

    PubMed Central

    Singh, Sudha B.; Lin, Henry C.

    2015-01-01

    Hydrogen sulfide (H2S) is a Janus-faced molecule. On one hand, several toxic functions have been attributed to H2S and exposure to high levels of this gas is extremely hazardous to health. On the other hand, H2S delivery based clinical therapies are being developed to combat inflammation, visceral pain, oxidative stress related tissue injury, thrombosis and cancer. Since its discovery, H2S has been found to have pleiotropic effects on physiology and health. H2S is a gasotransmitter that exerts its effect on different systems, such as gastrointestinal, neuronal, cardiovascular, respiratory, renal, and hepatic systems. In the gastrointestinal tract, in addition to H2S production by mammalian cystathionine-β-synthase (CBS), cystathionine-γ-lyase (CSE), H2S is also generated by the metabolic activity of resident gut microbes, mainly by colonic Sulfate-Reducing Bacteria (SRB) via a dissimilatory sulfate reduction (DSR) pathway. In the gut, H2S regulates functions such as inflammation, ischemia/ reperfusion injury and motility. H2S derived from gut microbes has been found to be associated with gastrointestinal disorders such as ulcerative colitis, Crohn’s disease and irritable bowel syndrome. This underscores the importance of gut microbes and their production of H2S on host physiology and pathophysiology. PMID:27682122

  12. Aspartic proteinases in the digestive tract of marine decapod crustaceans.

    PubMed

    Navarrete del Toro, María de Los Angeles; García-Carreño, Fernando; López, Manuel Díaz; Celis-Guerrero, Laura; Saborowski, Reinhard

    2006-08-01

    Decapod crustaceans synthesize highly active proteolytic enzymes in the midgut gland and release at least a part of them into the stomach where they facilitate the first step in peptide hydrolysis. The most common proteinases in the gastric fluid characterized so far are serine proteinases, that is, trypsin and chymotrypsin. These enzymes show highest activities at neutral or slightly alkaline conditions. The presence of acid proteinases, as they prevail in vertebrates, has been discussed contradictorily yet in invertebrates. In this study, we show that acid aspartic proteinases appear in the gastric fluid of several decapods. Lobsters Homarus gammarus showed the highest activity with a maximum at pH 3. These activities were almost entirely inhibited by pepstatin A, which indicates a high share of aspartic proteinases. In other species (Panulirus interruptus, Cancer pagurus, Callinectes arcuatus and Callinectes bellicosus), proteolytic activities were present at acid conditions but were distinctly lower than in H. gammarus. Zymograms at pH 3 showed in each of the studied species at least one, but mostly two-four bands of activity. The apparent molecular weight of the enzymes ranged from 17.8 to 38.6 kDa. Two distinct bands were identified which were inhibited by pepstatin A. Acid aspartic proteinases may play an important role in the process of extracellular digestion in decapod crustaceans. Activities were significantly higher in clawed lobster than in spiny lobster and three species of brachyurans. Therefore, it may be suggested that the expression of acid proteinases is favored in certain groups and reduced in others. PMID:16788916

  13. [THE MICRO-ECOLOGY OF DIGESTIVE TRACT AS AN INDICATOR OF HUMAN HEALTH CONDITIONS].

    PubMed

    Samoukina, A M; Mikhailova, E S; Chervinets, V M; Mironov A Yu; Alekseeva, Yu A

    2015-06-01

    The study was carried out to analyze qualitative and quantitative parameters of oral fluid and feces in 74 healthy individuals of different age groups. In most of the cases, alterations of micro-ecology are established characterizing by decreasing of amount of indigenous micro-flora and increasing of number of opportunistic pathogenic microorganisms of genera of Staphylococcus, Bacillus, Candida. The degree of evidence of these alterations reliably increases with age. It is established that microbiota, initial and terminal biotopes of digestive tract are closely interrelated and have number of common characteristics depending on age, hormonal and immune status and reflect conditions of micro-biocenosis of digestive tract in general. The character and degree of evidence of alterations of micro-biocenosis can be an effective diagnostic criterion for complex evaluation of human health conditions with following formation of risk groups in need of particular volume of correction activities. PMID:26466455

  14. Taxonomic composition and physiological and biochemical properties of bacteria in the digestive tracts of earthworms

    NASA Astrophysics Data System (ADS)

    Byzov, B. A.; Tikhonov, V. V.; Nechitailo, T. Yu.; Demin, V. V.; Zvyagintsev, D. G.

    2015-03-01

    Several hundred bacterial strains belonging to different taxa were isolated and identified from the digestive tracts of soil and compost earthworms. Some physiological and biochemical properties of the bacteria were characterized. The majority of intestinal bacteria in the earthworms were found to be facultative anaerobes. The intestinal isolates as compared to the soil ones had elevated activity of proteases and dehydrogenases. In addition, bacteria associated with earthworms' intestines are capable of growth on humic acids as a sole carbon source. Humic acid stimulated the growth of the intestinal bacteria to a greater extent than those of the soil ones. In the digestive tracts, polyphenol oxidase activity was found. Along with the data on the taxonomic separation of the intestinal bacteria, the features described testified to the presence of a group of bacteria in the earthworms intestines that is functionally characteristic and is different from the soil bacteria.

  15. The association between biliary tract inflammation and risk of digestive system cancers

    PubMed Central

    Tsai, Tsung-Yu; Lin, Che-Chen; Peng, Cheng-Yuan; Huang, Wen-Hsin; Su, Wen-Pang; Lai, Shih-Wei; Chen, Hsuan-Ju; Lai, Hsueh-Chou

    2016-01-01

    Abstract The relationship between biliary tract inflammation (BTI) and digestive system cancers is unclear. This study aimed to evaluate the association between BTI and the risks of digestive system cancers. Using the Taiwan National Health Insurance claims data, information on a cohort of patients diagnosed with BTI (n = 4398) between 2000 and 2009 was collected. A comparison cohort of sex-, age-, and index year-matched persons without BTI (n = 17,592) was selected from the same database. The disease was defined by the ICD-9-CM. Both cohorts were followed until the end of 2010 and incidences of digestive system cancers were calculated. The results revealed an increase in adjusted hazard ratio (aHR) of biliary tract cancer (24.45; 95% confidence interval [CI]: 9.20–65.02), primary liver cancer (1.53; 95% CI: 1.07–2.18), and pancreatic cancer (3.10; 95% CI: 1.20–8.03) in patients with both gallbladder and BTI. The aHR of stomach cancer was also found to be increased (2.73; 95% CI: 1.28–5.81) in patients with gallbladder inflammation only. There were no differences in esophageal cancer (aHR: 0.82; 95% CI: 0.23–2.87) and colorectal cancer (aHR: 0.92; 95% CI: 0.59–1.45). The aHR for digestive system cancers increased by 3.66 times (95% CI: 2.50–5.35) and 12.20 times (95% CI: 8.66–17.17) in BTI visits frequency averaged 2 to 4 visits per year and frequency averaged ≥5 visits per year, respectively. Patients with BTI have significantly higher risk of digestive system cancers, particularly biliary tract, pancreatic, and primary liver cancers, compared with those who are without it. PMID:27495065

  16. Histopathological study of toxic effects of carbaryl on digestive tract of Bufotes variabilis (Anura: Bufonidae).

    PubMed

    Çakıcı, Özlem

    2016-07-01

    Due to the negative effects of pesticide usage in environment, i.e., decline in amphibian populations, this study was designed to examine histopathologic changes following carbaryl exposure for 96 h in the digestive tract of variable toad, Bufotes variabilis. After exposure to single doses of carbaryl (low dose 50 μg/g, medium dose 100 μg/g, and high dose: 200 μg/g), the toads were euthanized and dissected and digestive tract samples were quickly removed. Histopathology revealed esophageal vacuolization and necrosis in esophageal cells. Hemorrhage was also observed in the esophagus. In the stomach, necrosis in the glandular epithelium, congested blood vessels, edema among gastric glands, dilated tips of the mucosal epithelial layer, gastric glandular atrophy, and hemorrhage were found. In the intestine, edema within villi, hemorrhage, inflammation, vacuolization, and necrosis in epithelial cells of villi were detected. This study clearly showed that carbaryl caused adverse effects on the digestive tract of B. variabilis in all dose groups. PMID:27026545

  17. Histopathological study of toxic effects of carbaryl on digestive tract of Bufotes variabilis (Anura: Bufonidae).

    PubMed

    Çakıcı, Özlem

    2016-07-01

    Due to the negative effects of pesticide usage in environment, i.e., decline in amphibian populations, this study was designed to examine histopathologic changes following carbaryl exposure for 96 h in the digestive tract of variable toad, Bufotes variabilis. After exposure to single doses of carbaryl (low dose 50 μg/g, medium dose 100 μg/g, and high dose: 200 μg/g), the toads were euthanized and dissected and digestive tract samples were quickly removed. Histopathology revealed esophageal vacuolization and necrosis in esophageal cells. Hemorrhage was also observed in the esophagus. In the stomach, necrosis in the glandular epithelium, congested blood vessels, edema among gastric glands, dilated tips of the mucosal epithelial layer, gastric glandular atrophy, and hemorrhage were found. In the intestine, edema within villi, hemorrhage, inflammation, vacuolization, and necrosis in epithelial cells of villi were detected. This study clearly showed that carbaryl caused adverse effects on the digestive tract of B. variabilis in all dose groups.

  18. Genotypic adaptations associated with prolonged persistence of Lactobacillus plantarum in the murine digestive tract.

    PubMed

    van Bokhorst-van de Veen, Hermien; Smelt, Maaike J; Wels, Michiel; van Hijum, Sacha A F T; de Vos, Paul; Kleerebezem, Michiel; Bron, Peter A

    2013-08-01

    Probiotic bacteria harbor effector molecules that confer health benefits, but also adaptation factors that enable them to persist in the gastrointestinal tract of the consumer. To study these adaptation factors, an antibiotic-resistant derivative of the probiotic model organism Lactobacillus plantarum WCFS1 was repeatedly exposed to the mouse digestive tract by three consecutive rounds of (re)feeding of the longest persisting colonies. This exposure to the murine intestine allowed the isolation of intestine-adapted derivatives of the original strain that displayed prolonged digestive tract residence time. Re-sequencing of the genomes of these adapted derivatives revealed single nucleotide polymorphisms as well as a single nucleotide insertion in comparison with the genome of the original WCFS1 strain. Detailed in silico analysis of the identified genomic modifications pinpointed that alterations in the coding regions of genes encoding cell envelope associated functions and energy metabolism appeared to be beneficial for the gastrointestinal tract survival of L. plantarum WCFS1. This work demonstrates the feasibility of experimental evolution for the enhancement of the gastrointestinal residence time of probiotic strains, while full-genome resequencing of the adapted isolates provided clues towards the bacterial functions involved. Enhanced gastrointestinal residence is industrially relevant because it enhances the efficacy of the delivery of viable probiotics in situ.

  19. Lignocellulolytic enzymes and bacteria associated with the digestive tracts of Stenochironomus (Diptera: Chironomidae) larvae.

    PubMed

    Koroiva, R; Souza, C W O; Toyama, D; Henrique-Silva, F; Fonseca-Gessner, A A

    2013-01-01

    We analyzed the digestive activity of the enzymes that digest cellulose and hemicellulose and the bacterial community that is capable of hydrolyzing wood compounds in the digestive tracts of Stenochironomus (Diptera: Chironomidae) larvae, which are miners of decomposing submerged tree and bush branches. Based on quantification of reducing sugars, these larvae have a limited capacity for cellulose degradation but a good capacity for xylan hydrolysis. We isolated 31 types of colonies from two larval morphotypes, of which 19 tested positive for the capacity to hydrolyze at least one of the four substrates that were used as the main carbon source in the culture media. Their woody compound degradation capacity was assessed using colorimetric tests. The bacteria were identified by the analysis of the 16S rRNA gene. None of the bacteria were capable of degrading lignin. The genus Pseudomonas had the greatest species richness; Bacillus spp exhibited the greatest capacity for degrading the different substrates, and Sphingobium was found in both morphotypes. Microorganisms participate in the degradation of wood consumed by Stenochironomus larvae. This is the first report of lignocellulolytic bacteria and enzymes in the digestive tracts of mining chironomids.

  20. A method to directly measure maximum volume of fish stomachs or digestive tracts

    USGS Publications Warehouse

    Burley, C.C.; Vigg, S.

    1989-01-01

    A new method for measuring maximum stomach or digestive tract volume of fish incorporates air injection at constant pressure with water displacement to measure directly the internal volume of a stomach or analogous structure. The method was tested with coho salmon, Oncorhynchus kisutch (Walbaum), which has a true stomach, and northern squawfish, Ptychocheilus oregonensis(Richardson), which has a modified foregut as a functional analogue. Both species were collected during July-October 1987 from the Columbia River, U.S.A. Relationships between fish weight (= volume) and maximum volume of the digestive organ were best fitted for coho salmon by an allometric model and for northern squawfish by an exponential model. Least squares regression analysis of individual measurements showed less variability in the volume of coho salmon stomachs (R2= 0.85) than in the total digestive tracts (R2= 0.55) and foreguts (R2= 0.61) of northern squawfish, relative to fish size. Compared to previous methods, the new technique has the advantage of accurately measuring the internal volume of a wide range of digestive organ shapes and sizes.

  1. Short-term fate of dietary dieldrin in the digestive tract of juvenile lake trout (Salvelinus namaycush)

    USGS Publications Warehouse

    Stewart, Donald J.; Stein, Roy A.

    1974-01-01

    Short-term fate of dietary dieldrin in the digestive tract of fishes is poorly known. Studies of the uptake, distribution, and elimination of chlorinated hydrocarbons have suggested that uptake or degradation is rapid in the intestine (GROSS 1969; MACEK et al. 1970; GRZENDA et al. 1970, 1971). The present study was designed to determine the short-term fate of a single oral dose of dieldrin in the digestive tract of lake trout (Salvelinus namaycush).

  2. Detection of Helicobacter in the digestive tract of an Atlantic spotted dolphin (Stenella frontalis).

    PubMed

    Suárez, Paula; Contreras, Monica; Fernández-Delgado, Milagro; Salazar, Victor; Peña, Ruth; Michelangeli, Fabian; García-Amado, M Alexandra

    2010-04-01

    Helicobacter spp. occur in the digestive system of a broad range of animal taxa, including marine mammals. Only one formally recognized species, Helicobacter cetorum, has been described in marine mammals. Helicobacter has not been reported in the Atlantic spotted dolphin (Stenella frontalis). The purpose of our study was to examine the digestive tract of a stranded spotted dolphin for Helicobacter. Tissue and content samples were collected at necropsy and examined by histopathology and molecular analyses using Helicobacter genus-specific 16S rDNA polymerase chain reaction (PCR) and DNA sequencing. Helicobacter was detected in all stomach divisions and the duodenal ampulla. A sequence type of the 16S rRNA gene shared a 98-99% identity to sequences from H. cetorum. This study reports for the first time Helicobacter in S. frontalis. PMID:20688662

  3. Cancer screening via infrared spectral cytopathology (SCP): results for the upper respiratory and digestive tracts.

    PubMed

    Diem, Max; Miljković, Miloš; Bird, Benjamin; Mazur, Antonella I; Schubert, Jen M; Townsend, Douglas; Laver, Nora; Almond, Max; Old, Oliver

    2016-01-21

    Instrumental advances in infrared micro-spectroscopy have made possible the observation of individual human cells and even subcellular structures. The observed spectra represent a snapshot of the biochemical composition of a cell; this composition varies subtly but reproducibly with cellular effects such as progression through the cell cycle, cell maturation and differentiation, and disease. The aim of this summary is to provide a synopsis of the progress achieved in infrared spectral cytopathology (SCP) - the combination of infrared micro-spectroscopy and multivariate methods of analysis - for the detection of abnormalities in exfoliated human cells of the upper respiratory and digestive tract, namely the oral and nasopharyngeal cavities, and the esophagus.

  4. Nutritional support in patients with GVHD of the digestive tract: state of the art.

    PubMed

    van der Meij, B S; de Graaf, P; Wierdsma, N J; Langius, J A E; Janssen, J J W M; van Leeuwen, P A M; Visser, O J

    2013-04-01

    An important complication of allo-SCT is GVHD, which commonly affects the skin, liver and digestive tract. Clinical symptoms of GVHD of the digestive tract (GVHD-DT) include excessive diarrhoea, abdominal pain and cramps, nausea and vomiting, gastrointestinal bleeding, dysphagia, and weight loss. Treatment is complicated and regarding nutritional support, only a few guidelines are available. Our aim was to critically appraise the literature on nutritional assessment, nutritional status and nutritional support for patients with GVHD-DT. Evidence shows that GVHD-DT is often associated with malnutrition, protein losing enteropathy, magnesium derangements, and deficiencies of zinc, vitamin B12 and vitamin D. Limited evidence exists on derangements of magnesium, resting energy expenditure, bone mineral density and pancreatic function, and some beneficial effects of n-3 polyunsaturated fatty acids and pancreatic enzyme replacement therapy. Expert opinions recommend adequate amounts of energy, at least 1.5 g protein/kg body weight, supplied by total parenteral nutrition in cases of severe diarrhoea. When diarrhoea is <500 mL a day, a stepwise oral upgrade diet can be followed. No studies exist on probiotics, prebiotics, dietary fibre and immunonutrition in GVHD-DT patients. Future research should focus on absorption capacity, vitamin and mineral status, and nutritional support strategies.

  5. Kicking in the Guts: Schistosoma mansoni Digestive Tract Proteins are Potential Candidates for Vaccine Development

    PubMed Central

    Figueiredo, Barbara Castro-Pimentel; Ricci, Natasha Delaqua; de Assis, Natan Raimundo Gonçalves; de Morais, Suellen Batistoni; Fonseca, Cristina Toscano; Oliveira, Sergio Costa

    2015-01-01

    Schistosomiasis is a debilitating disease that represents a major health problem in at least 74 tropical and subtropical countries. Current disease control strategies consist mainly of chemotherapy, which cannot prevent recurrent re-infection of people living in endemic area. In the last decades, many researchers made a remarkable effort in the search for an effective vaccine to provide long-term protection. Parasitic platyhelminthes of Schistosoma genus, which cause the disease, live in the blood vessels of definitive hosts where they are bathed in host blood for many years. Among the most promising molecules as vaccine candidates are the proteins present in the host–parasite interface, so numerous tegument antigens have been assessed and the achieved protection never got even close to 100%. Besides the tegument, the digestive tract is the other major site of host–parasite interface. Since parasites feed on blood, they need to swallow a considerable amount of blood for nutrient acquisition. Host blood ingested by schistosomes passes through the esophagus and reaches the gut where many peptidases catalyze the proteolysis of blood cells. Recent studies show the emergence of antigens related to the parasite blood feeding, such as esophageal gland proteins, proteases, and other proteins related to nutrient uptake. Herein, we review what is known about Schistosoma mansoni digestive tract proteins, emphasizing the ones described as potential vaccine candidates. PMID:25674091

  6. Methane Production and Methanogenic Archaea in the Digestive Tracts of Millipedes (Diplopoda)

    PubMed Central

    Šustr, Vladimír; Chroňáková, Alica; Semanová, Stanislava; Tajovský, Karel; Šimek, Miloslav

    2014-01-01

    Methane production by intestinal methanogenic Archaea and their community structure were compared among phylogenetic lineages of millipedes. Tropical and temperate millipedes of 35 species and 17 families were investigated. Species that emitted methane were mostly in the juliform orders Julida, Spirobolida, and Spirostreptida. The irregular phylogenetic distribution of methane production correlated with the presence of the methanogen-specific mcrA gene. The study brings the first detailed survey of methanogens’ diversity in the digestive tract of millipedes. Sequences related to Methanosarcinales, Methanobacteriales, Methanomicrobiales and some unclassified Archaea were detected using molecular profiling (DGGE). The differences in substrate preferences of the main lineages of methanogenic Archaea found in different millipede orders indicate that the composition of methanogen communities may reflect the differences in available substrates for methanogenesis or the presence of symbiotic protozoa in the digestive tract. We conclude that differences in methane production in the millipede gut reflect differences in the activity and proliferation of intestinal methanogens rather than an absolute inability of some millipede taxa to host methanogens. This inference was supported by the general presence of methanogenic activity in millipede faecal pellets and the presence of the 16S rRNA gene of methanogens in all tested taxa in the two main groups of millipedes, the Helminthophora and the Pentazonia. PMID:25028969

  7. Mesenchymal-epithelial interactions during digestive tract development and epithelial stem cell regeneration.

    PubMed

    Le Guen, Ludovic; Marchal, Stéphane; Faure, Sandrine; de Santa Barbara, Pascal

    2015-10-01

    The gastrointestinal tract develops from a simple and uniform tube into a complex organ with specific differentiation patterns along the anterior-posterior and dorso-ventral axes of asymmetry. It is derived from all three germ layers and their cross-talk is important for the regulated development of fetal and adult gastrointestinal structures and organs. Signals from the adjacent mesoderm are essential for the morphogenesis of the overlying epithelium. These mesenchymal-epithelial interactions govern the development and regionalization of the different gastrointestinal epithelia and involve most of the key morphogens and signaling pathways, such as the Hedgehog, BMPs, Notch, WNT, HOX, SOX and FOXF cascades. Moreover, the mechanisms underlying mesenchyme differentiation into smooth muscle cells influence the regionalization of the gastrointestinal epithelium through interactions with the enteric nervous system. In the neonatal and adult gastrointestinal tract, mesenchymal-epithelial interactions are essential for the maintenance of the epithelial regionalization and digestive epithelial homeostasis. Disruption of these interactions is also associated with bowel dysfunction potentially leading to epithelial tumor development. In this review, we will discuss various aspects of the mesenchymal-epithelial interactions observed during digestive epithelium development and differentiation and also during epithelial stem cell regeneration. PMID:26126787

  8. [Aerobic bacterial flora from the digestive tract of the common vampire bat, Desmodus rotundus (Chiroptera: Phyllostomidae)].

    PubMed

    Chaverri, Gloriana

    2006-09-01

    This study addresses the composition of microbial flora in the vampire bat (Desmodus rotundus) primarily because all available data are outdated, and because of the economical significance of this bat species. Twenty-one bats were collected and their aerobic bacteria documented separately for stomach and intestine. Bacteria were identified through the Analytical Profile Index (API), and results analyzed with the APILAB software. A total of thirty bacterial species were isolated from sixteen females and five males. The most common species were Escherichia coli and Staphylococcus aureus, although other bacteria, such as Acinetobacterjohnsonii, Enterobacter sakazakii, Staphylococcus chromogenes, S. hyicus and S. xylosus were also common. The number of species found in the stomach and intestine was significantly different, and the intestine presented a higher diversity compared to the stomach. This has previously been found in other mammals and it is attributed to a reduction of acidity. Most of the species found in this study are considered normal components of the digestive tract of mammals, although other bacteria common in the skin of mammals and from aquatic environments were found. Bacteria from the skin may invade the vampire's stomach and/or intestine when the bat has contact with its prey, and may suggest that the vampire's feeding habit facilitates the invasion of other microbes not common in its digestive tract. The fact that bacteria from aquatic environments were also found suggests that D. rotundus, as previously found by other researchers, drinks free water when available, and water may be another source of microbial invasion.

  9. Methane production and methanogenic Archaea in the digestive tracts of millipedes (Diplopoda).

    PubMed

    Šustr, Vladimír; Chroňáková, Alica; Semanová, Stanislava; Tajovský, Karel; Šimek, Miloslav

    2014-01-01

    Methane production by intestinal methanogenic Archaea and their community structure were compared among phylogenetic lineages of millipedes. Tropical and temperate millipedes of 35 species and 17 families were investigated. Species that emitted methane were mostly in the juliform orders Julida, Spirobolida, and Spirostreptida. The irregular phylogenetic distribution of methane production correlated with the presence of the methanogen-specific mcrA gene. The study brings the first detailed survey of methanogens' diversity in the digestive tract of millipedes. Sequences related to Methanosarcinales, Methanobacteriales, Methanomicrobiales and some unclassified Archaea were detected using molecular profiling (DGGE). The differences in substrate preferences of the main lineages of methanogenic Archaea found in different millipede orders indicate that the composition of methanogen communities may reflect the differences in available substrates for methanogenesis or the presence of symbiotic protozoa in the digestive tract. We conclude that differences in methane production in the millipede gut reflect differences in the activity and proliferation of intestinal methanogens rather than an absolute inability of some millipede taxa to host methanogens. This inference was supported by the general presence of methanogenic activity in millipede faecal pellets and the presence of the 16S rRNA gene of methanogens in all tested taxa in the two main groups of millipedes, the Helminthophora and the Pentazonia.

  10. Radium-contaminated water: a risk factor for cancer of the upper digestive tract.

    PubMed

    Hirunwatthanakul, Phatcha; Sriplung, Hutcha; Geater, Alan

    2006-01-01

    There is a high incidence of oral, pharynx and esophagus cancer among males in Na Mom district in Songkhla Province in Thailand, an area where radium concentration in shallow well water is found to be higher than other areas in this province. A population-based case control study was conducted from June to November 2004 to determine the association of oral exposure to radium-contaminated water and cancer of the upper digestive tract in the district.Thirty-two confirmed cases and 128 sex and five-year birth cohort matched neighborhood controls were selected by multistage sampling from six villages in four sub-districts. All subjects were verified to have been permanent residents in the district for more than 10 years. Thirty cases were dead at the time of the study, thus their relatives were interviewed to determine their amount of water drinking, tobacco smoking, alcohol drinking, betel chewing and exposure to other potential risk factors in the past. The other two cases and all controls were directly interviewed. The concentration of radium in shallow well water at the subject's houses was estimated using a contour map of Ra-226 in the water at the location of their residence. The results showed a strong and dose-dependent associationb etween consumption of radium-contaminated shallow well water and cancer of the upper digestive tract. In multivariate analysis controlled for important risk factors of the cancer, the odds ratios for exposure to oral radium consumption 50-100 mBq/day and >100 mBq/day compared with <50 mBq/day were 2.83 (95% CI: 0.50-16.19) and 29.76 (95% CI: 4.39-201.6) respectively. The risk also increased with consumption of fresh water fish which might have been contaminated by dissolved radium in the water. This study offers the first evidence of the association between radium and cancer of the upper digestive tract to the world literature. Further studies with other methods such as area-wide correlation of radium-uranium concentration and the

  11. Radium-contaminated water: a risk factor for cancer of the upper digestive tract.

    PubMed

    Hirunwatthanakul, Phatcha; Sriplung, Hutcha; Geater, Alan

    2006-01-01

    There is a high incidence of oral, pharynx and esophagus cancer among males in Na Mom district in Songkhla Province in Thailand, an area where radium concentration in shallow well water is found to be higher than other areas in this province. A population-based case control study was conducted from June to November 2004 to determine the association of oral exposure to radium-contaminated water and cancer of the upper digestive tract in the district.Thirty-two confirmed cases and 128 sex and five-year birth cohort matched neighborhood controls were selected by multistage sampling from six villages in four sub-districts. All subjects were verified to have been permanent residents in the district for more than 10 years. Thirty cases were dead at the time of the study, thus their relatives were interviewed to determine their amount of water drinking, tobacco smoking, alcohol drinking, betel chewing and exposure to other potential risk factors in the past. The other two cases and all controls were directly interviewed. The concentration of radium in shallow well water at the subject's houses was estimated using a contour map of Ra-226 in the water at the location of their residence. The results showed a strong and dose-dependent associationb etween consumption of radium-contaminated shallow well water and cancer of the upper digestive tract. In multivariate analysis controlled for important risk factors of the cancer, the odds ratios for exposure to oral radium consumption 50-100 mBq/day and >100 mBq/day compared with <50 mBq/day were 2.83 (95% CI: 0.50-16.19) and 29.76 (95% CI: 4.39-201.6) respectively. The risk also increased with consumption of fresh water fish which might have been contaminated by dissolved radium in the water. This study offers the first evidence of the association between radium and cancer of the upper digestive tract to the world literature. Further studies with other methods such as area-wide correlation of radium-uranium concentration and the

  12. Host Matters: Medicinal Leech Digestive-Tract Symbionts and Their Pathogenic Potential

    PubMed Central

    Marden, Jeremiah N.; McClure, Emily A.; Beka, Lidia; Graf, Joerg

    2016-01-01

    Digestive-tract microbiota exert tremendous influence over host health. Host-symbiont model systems are studied to investigate how symbioses are initiated and maintained, as well as to identify host processes affected by resident microbiota. The medicinal leech, Hirudo verbana, is an excellent model to address such questions owing to a microbiome that is consistently dominated by two species, Aeromonas veronii and Mucinivorans hirudinis, both of which are cultivable and have sequenced genomes. This review outlines current knowledge about the dynamics of the H. verbana microbiome. We discuss in depth the factors required for A. veronii colonization and proliferation in the leech crop and summarize the current understanding of interactions between A. veronii and its annelid host. Lastly, we discuss leech usage in modern medicine and highlight how leech-therapy associated infections, often attributable to Aeromonas spp., are of growing clinical concern due in part to an increased prevalence of fluoroquinolone resistant strains. PMID:27790190

  13. [Reduction of plant fibers in the digestive tract of the moose and the red deer].

    PubMed

    Naumova, E I; Zharova, G K; Chistova, T Iu; Danilkin, A A

    2012-01-01

    A comparative study of the reduction of plant fibers moving in the digestive tract of nine red deer (Cervus elaphus) and six moose (Alces alces) was made. In the winter season, the character of fiber reduction in the moose and the red deer was similar. In the deer obtained in the early autumn, the relative concentration of small-sized fractions was significantly higher. A sharp decrease in the share oflarge-sized fibers was observed in the omasum as compared to the rumen and the reticulum. It was especially pronounced in the deer obtained in September. Deceleration of fibers of large-sized fractions in the rumen and the reticulum and the structure of the reticulo-omasal opening and its functions were considered.

  14. The digestive tract of rat after flight in the biosatellite Cosmos 1667.

    PubMed

    Groza, P; Bordeianu, A; Boca, A

    1987-01-01

    From the histochemical investigation carried out on the digestive tract of rats after 7 days space flight in the soviet biosatellite Cosmos 1667 it resulted that neutral and acid glycoproteins diminished slightly in the sublingual gland, stomach, small intestine and the colon. Some intestinal enzymes augmented (leucineaminopeptidase, acid phosphatase, adenosinetriphosphatase and glucose-6-phosphatase). The changes observed after this flight were less marked than after an 18 day flight (in the Soviet biosatellite Cosmos 936 and 1129) and similar to those revealed after 7 days of hypokinesia. The glycoprotein changes were close to those observed after a 5-day flight (Cosmos 1514) but in which there were pregnant rats; after these last flights, the enzymes were not studied.

  15. Digestive tract absorption of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in a nursing infant

    SciTech Connect

    McLachlan, M.S. )

    1993-11-01

    The digestive tract absorption of environmental contaminants is an important but poorly understood parameter in contaminant is an important but poorly understood parameter in contaminant risk assessments. The net absorption of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in a nursing infant was measured under natural conditions over 12 days. The levels of the substances in the mother's milk were typical for Germany. It was found that for almost all congeners over 90% of the ingested compound was absorbed. This indicates that the common assumption of 100% absorption in nursing infants is reasonable. No firm conclusions could be drawn regarding the absorption of Cl7- and Cl8DD/F due to high blank levels in the cotton diapers used.

  16. Statistical analyses on the pattern of food consumption and digestive-tract cancers in Japan.

    PubMed

    Hara, N; Sakata, K; Nagai, M; Fujita, Y; Hashimoto, T; Yanagawa, H

    1984-01-01

    The relationships between areal differences in mortality from six digestive-tract cancers and consumption of selected foods in 46 of the 47 Japanese prefectures (Okinawa being excluded) were analyzed. Statistical analyses disclosed that the groups of foods positively associated with cancer death were as follows: for esophageal cancer, pork, oil, popular-grade sake, and green tea; for stomach cancer, fresh fish, salted or dried fish, salt, and special-grade sake; for colon cancer, bread, milk, butter, margarine, ketchup, beer, and salted or dried fish; for rectal cancer, fresh fish, salted or dried fish, salt, and popular-grade sake; for cancer of the biliary passages, pork, popular-grade sake, and green tea; and for pancreatic cancer, oil, mayonnaise, fresh fish, and salted or dried fish. These results are based on statistical analyses. Further epidemiological analyses are required to find a biological causal relationship. PMID:6545578

  17. Novel ß-HPV49 Transgenic Mouse Model of Upper Digestive Tract Cancer.

    PubMed

    Viarisio, Daniele; Müller-Decker, Karin; Zanna, Paola; Kloz, Ulrich; Aengeneyndt, Birgit; Accardi, Rosita; Flechtenmacher, Christa; Gissmann, Lutz; Tommasino, Massimo

    2016-07-15

    The beta genus of human papillomaviruses (ß-HPV) includes approximately 50 different viral types that are subdivided into five species (ß-1 through ß-5). Nonmelanoma cancers may involve some ß-1 and ß-2 HPV types, but the biology of most ß-HPV types and their possible connections to human disease are still little characterized. In this study, we studied the effects of ß-3 type HPV49 in a novel transgenic (Tg) mouse model, using a cytokeratin K14 promoter to drive expression of the E6 and E7 genes from this virus in the basal skin epidermis and the mucosal epithelia of the digestive tract (K14 HPV49 E6/E7-Tg mice). Viral oncogene expression only marginally increased cellular proliferation in the epidermis of Tg animals, compared with wild-type littermates, and we observed no spontaneous tumor formation during their entire lifespan. However, we found that K14 HPV49 E6/E7-Tg mice were highly susceptible to upper digestive tract carcinogenesis upon initiation with 4-nitroquinoline 1-oxide (4NQO). This was a selective effect, as the same mice did not exhibit any skin lesions after chronic UV irradiation. Opposite results were observed in an analogous Tg model expressing the ß-2 HPV38 E6 and E7 oncogenes at the same anatomic sites. While these mice were highly susceptible to UV-induced skin carcinogenesis, as previously shown, they were little affected by 4NQO treatment. Overall, our findings highlight important differences in the biologic properties of certain ß-type HPV that affect their impact on carcinogenesis in an anatomic site-specific manner. Cancer Res; 76(14); 4216-25. ©2016 AACR.

  18. Interaction of Vibrio spp. with the Inner Surface of the Digestive Tract of Penaeus monodon

    PubMed Central

    Soonthornchai, Wipasiri; Chaiyapechara, Sage; Jarayabhand, Padermsak; Söderhäll, Kenneth; Jiravanichpaisal, Pikul

    2015-01-01

    Several species of Vibrio are the causative agent of gastroenteritis in humans. In aquaculture, Vibrio harveyi (Vh) and V. parahaemolyticus (Vp) have long been considered as shrimp pathogens in freshwater, brackish and marine environments. Here we show by using scanning electron microscopy (SEM) that Penaeus monodon orally inoculated with each of these two pathogens via an Artemia diet had numerous bacteria attached randomly across the stomach surface, in single and in large biofilm-like clusters 6 h post-infection. A subsequent marked proliferation in the number of V. harveyi within the biofilm-like formations resulted in the development of infections in the stomach, the upper and middle midgut, but neither in the posterior midgut nor the hindgut. SEM also revealed the induced production of peritrichous pili-like structures by the Vp attaching to the stomach lining, whilst only a single polar fibre was seen forming an apparent physical bridge between Vh and the host’s epithelium. In contrast to these observations, no such adherences or linkages were seen when trials were conducted with non-pathogenic Vibrio spp. or with Micrococcus luteus, with no obvious resultant changes to the host’s gut surface. In naive shrimp, the hindgut was found to be a favorable site for bacteria notably curved, short-rod shaped bacteria which probably belong to Vibrio spp. Data from the current study suggests that pathogens of P. monodon must be able to colonize the digestive tract, particularly the stomach, where chitin is present, and then they use an array of virulent factors and enzymes to infect their host resulting in disease. Oral infection is a better way of mimicking natural routes of infection; investigating the host-bacteria interactions occurring in the digestive tract may lead to new strategies for the prevention or control of bacterial infections in penaeids. PMID:26285030

  19. Anaplastic Lymphoma Kinase Rearrangement in Digestive Tract Cancer: Implication for Targeted Therapy in Chinese Population

    PubMed Central

    Wu, Jian; Guo, Lei; Qiu, Tian; Ling, Yun; Shan, Ling; Zhou, Haitao; Zhao, Dongbing; Wang, Jian; Liang, Jianwei; Zhao, Jianjun; Jiao, Yuchen; Lu, Ning; Zhao, Hong

    2015-01-01

    Background Anaplastic lymphoma kinase (ALK) rearrangements define a subgroup of lung cancer which is eligible to targeted kinase inhibition. The aim of this study is to observe the incidence rate of ALK fusion in a large cohort of Chinese digestive tract cancer patients. Patients and Methods Tissue microarray (TMA) was constructed from 808 digestive tract cancer cases, including 169 esophageal squamous cell carcinoma, 182 gastric cancer and 457 colorectal cancer (CRC) cases. We tested all cases for ALK expression via a fully automated immunohistochemistry (IHC) assay. The IHC-positive cases were subjected to fluorescence in situ hybridization (FISH), real-time polymerase chain reaction (qRT-PCR), target gene enrichment and sequencing for confirmation of ALK gene rearrangement and discovery of novel fusion partner. Results Among the tested cases, 2 (0.44%) CRC cases showed positive both by IHC and FISH. By qRT-PCR, EML4–ALK fusion was found in one IHC-positive CRC case. In another IHC-positive CRC case, target gene enrichment and sequencing revealed ALK was fused to a novel partner, spectrin beta non-erythrocytic 1 (SPTBN1). One gastric cancer case showed partially positive IHC result, but no fusion was found by FISH and gene sequencing. Conclusions The incidence rate of ALK gene fusion in Chinese CRC patients was 0.44%,but not detectable in gastric and esophageal cancers. The novel SPTBN1 -ALK fusion, together with other ALK fusion genes, may become a potential target for anti-ALK therapy. PMID:26678488

  20. Novel ß-HPV49 Transgenic Mouse Model of Upper Digestive Tract Cancer.

    PubMed

    Viarisio, Daniele; Müller-Decker, Karin; Zanna, Paola; Kloz, Ulrich; Aengeneyndt, Birgit; Accardi, Rosita; Flechtenmacher, Christa; Gissmann, Lutz; Tommasino, Massimo

    2016-07-15

    The beta genus of human papillomaviruses (ß-HPV) includes approximately 50 different viral types that are subdivided into five species (ß-1 through ß-5). Nonmelanoma cancers may involve some ß-1 and ß-2 HPV types, but the biology of most ß-HPV types and their possible connections to human disease are still little characterized. In this study, we studied the effects of ß-3 type HPV49 in a novel transgenic (Tg) mouse model, using a cytokeratin K14 promoter to drive expression of the E6 and E7 genes from this virus in the basal skin epidermis and the mucosal epithelia of the digestive tract (K14 HPV49 E6/E7-Tg mice). Viral oncogene expression only marginally increased cellular proliferation in the epidermis of Tg animals, compared with wild-type littermates, and we observed no spontaneous tumor formation during their entire lifespan. However, we found that K14 HPV49 E6/E7-Tg mice were highly susceptible to upper digestive tract carcinogenesis upon initiation with 4-nitroquinoline 1-oxide (4NQO). This was a selective effect, as the same mice did not exhibit any skin lesions after chronic UV irradiation. Opposite results were observed in an analogous Tg model expressing the ß-2 HPV38 E6 and E7 oncogenes at the same anatomic sites. While these mice were highly susceptible to UV-induced skin carcinogenesis, as previously shown, they were little affected by 4NQO treatment. Overall, our findings highlight important differences in the biologic properties of certain ß-type HPV that affect their impact on carcinogenesis in an anatomic site-specific manner. Cancer Res; 76(14); 4216-25. ©2016 AACR. PMID:27216183

  1. Complete Genome Sequence of Streptococcus salivarius HSISS4, a Human Commensal Bacterium Highly Prevalent in the Digestive Tract.

    PubMed

    Mignolet, Johann; Fontaine, Laetitia; Kleerebezem, Michiel; Hols, Pascal

    2016-01-01

    The human commensal bacterium Streptococcus salivarius plays a major role in the equilibrium of microbial communities of the digestive tract. Here, we report the first complete genome sequence of a Streptococcus salivarius strain isolated from the small intestine, namely, HSISS4. Its circular chromosome comprises 1,903 coding sequences and 2,100,988 nucleotides. PMID:26847886

  2. Complete Genome Sequence of Streptococcus salivarius HSISS4, a Human Commensal Bacterium Highly Prevalent in the Digestive Tract

    PubMed Central

    Fontaine, Laetitia; Kleerebezem, Michiel

    2016-01-01

    The human commensal bacterium Streptococcus salivarius plays a major role in the equilibrium of microbial communities of the digestive tract. Here, we report the first complete genome sequence of a Streptococcus salivarius strain isolated from the small intestine, namely, HSISS4. Its circular chromosome comprises 1,903 coding sequences and 2,100,988 nucleotides. PMID:26847886

  3. A cooperative study on the standardized total-tract digestible phosphorus requirement of twenty-kilogram pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cooperative studies comprising growth performance, bone mineralization, and nutrient balance experiments were conducted at 11 stations to determine the standardized total-tract digestible (STTD) P requirement of 20-kg pigs using broken-line regression analysis. Monocalcium phosphate and limestone we...

  4. Palliative stenting of the digestive tract: a case series of a single centre

    PubMed Central

    Dekkers, Pascale E.P.

    2013-01-01

    Background and aim Obstruction of the gastrointestinal tract due to cancer can be treated with stenting. The aim was to review the local experience with endoscopic stenting. All patients treated with stenting in a ten years period from 2001-2010 were studied. Results Fifty one patients received 57 stents because of oesophageal cancer. Mean survival after stent placement was 141 days. No case of perforation occurred. In nine cases (17%) clogging with food occurred. Tumour overgrowth was noted in four cases. Twenty four patients received 28 stents in their colon or rectum. The stents were placed in the rectum (n=6), the sigmoid (n=14), the descending colon (n=1), and the transverse colon (n=3). Mean survival was 276 days. Perforation did not occur. Tumour ingrowth was seen in two patients. One patient received a second stent. Dislocation occurred in two cases. There were two cases of clogging (8%) by stool. Fourteen patients received a total of 18 stents because of obstructing stomach cancer. Mean survival after placement was 121 days. There was no perforation, one case of clogging, and four cases of tumour ingrowth. Eight patients had stent placement in their duodenum. Mean survival after stent placement was 84 days. No perforation or clogging occurred. But three cases of tumour ingrowth were seen. Conclusions The present series shows that placement of expandable stents in the digestive tract in normal daily practice is feasible, safe, with a low number of complications, and provides good palliation for their remaining life. PMID:23450097

  5. Glycolytic Activities in the Larval Digestive Tract of Trypoxylus dichotomus (Coleoptera: Scarabaeidae)

    PubMed Central

    Wada, Noriko; Sunairi, Michio; Anzai, Hirosi; Iwata, Ryûtarô; Yamane, Akiomi; Nakajima, Mutsuyasu

    2014-01-01

    The larvae of the Japanese horned beetle, Trypoxylus dichotomus (Coleoptera: Scarabaeidae: Dynastinae), are an example of a saprophage insect. Generally, Scarabaeid larvae, such as T. dichotomus, eat dead plant matter that has been broken down by fungi, such as Basidiomycota. It is thought that β-1,3-glucan, a constituent polysaccharide in microbes, is abundant in decayed plant matter. Studies of the degradation mechanism of β-1,3-glucan under these circumstances are lacking. In the current study, we sought to clarify the relationship between the capacity to degrade polysaccharides and the food habits of the larvae. The total activities and optimum pH levels of several polysaccharide-degrading enzymes from the larvae were investigated. The foregut, midgut and hindgut of final instar larvae were used. Enzymatic activities were detected against five polysaccharides (soluble starch, β-1,4-xylan, β-1,3-glucan, pectin and carboxymethyl cellulose) and four glycosides (p-nitrophenyl (PNP)-β-N-acetylglucosaminide, PNP-β-mannoside, PNP-β-glucoside and PNP-β-xyloside). Our results indicate that the digestive tract of the larvae is equipped with a full enzymatic system for degrading β-1,3-glucan and β-1,4-xylan to monomers. This finding elucidates the role of the polysaccharide-digesting enzymes in the larvae, and it is suggested that the larvae use these enzymes to enact their decomposition ability in the forest environment. PMID:26462688

  6. Effect of corn silage hybrids differing in starch and neutral detergent fiber digestibility on lactation performance and total-tract nutrient digestibility by dairy cows.

    PubMed

    Ferraretto, L F; Fonseca, A C; Sniffen, C J; Formigoni, A; Shaver, R D

    2015-01-01

    Selection for hybrids with greater starch and NDF digestibility may be beneficial for dairy producers. The objective of this study was to determine the effect of feeding a TMR containing a floury-leafy corn silage hybrid (LFY) compared with a brown midrib corn silage hybrid (BMR) for intake, lactation performance, and total-tract nutrient digestibility in dairy cows. Ninety-six multiparous Holstein cows, 105±31d in milk at trial initiation, were stratified by DIM and randomly assigned to 12 pens of 8 cows each. Pens were randomly assigned to 1 of 2 treatments, BMR or LFY, in a completely randomized design; a 2-wk covariate period with cows fed a common diet followed by a 14-wk treatment period with cows fed their assigned treatment diet. Starch digestibilities, in situ, in vitro, and in vivo, were greater for LFY compared with BMR; the opposite was observed for NDF digestibility. Cows fed BMR consumed 1.7kg/d more dry matter than LFY. Although, actual-, energy-, and solids-corrected milk yields were greater for BMR than LFY, feed conversions (kg of milk or component-corrected milk per kg of DMI) did not differ. Fat-corrected milk and milk fat yield were similar, as milk fat content was greater for cows fed LFY (4.05%) than BMR (3.83%). Cows fed BMR had lower milk urea nitrogen concentration, but greater milk protein and lactose yields compared with LFY. Body weight change and condition score were unaffected by treatment. Total-tract starch digestibility was greater for cows fed the LFY corn silage; however, dry matter intake and milk and protein yields were greater for cows fed the BMR corn silage. Although total-tract starch digestibility was greater for cows fed the LFY corn silage, feed efficiency was not affected by hybrid type due to greater dry matter intake and milk and protein yields by cows fed the BMR corn silage.

  7. Mobilization of PAH and PCB from contaminated soil using a digestive tract model.

    PubMed

    Hack, A; Selenka, F

    1996-11-01

    Environmental contaminants are mainly incorporated by ingestion. In general only those contaminants mobilized by the digestive juices are available for absorption in the digestive tract, while pollutants still fixed to indigestible particles leave the body without any effect. To evaluate the different health risks arising from the ingestion of individual types of polluted soil or other materials, we developed an in vitro test system which simulates the transition of pollutants from contaminated materials into digestive juices by means of a standardized artificial gastro-intestinal model. The test system simulates the influence of the acidic environment of the stomach (gastric model) followed by the neutral or slightly alkaline environment of the small intestine (gastro-intestinal model). Investigations on small amounts of polluted soil, sewage sludge, asphalt, metal scrap and blast sand showed that the mobilization of polycyclic aromatic hydrocarbons (PAH) and polychlorinated biphenyls (PCB) by artificial gastric juice reaches 3% up to 22% of the pollutant concentration introduced into the test system. Elutions of the contaminated materials under gastric and subsequently under intestinal conditions with bile concentrations of 3 g/l resulted in PAH- and PCB-mobilizations in the range of 5% up to 40%. The degree of mobilization depends considerably on supplementary food material added to the test system. Lyophilized milk increased the fraction of mobilized PAH and PCB to 40%-85%. Application of the test system on 22 different contaminated soils showed that the mobilization of PAH under gastro-intestinal conditions with the addition of lyophilized milk ranged from 7% up to 95%, and the mobilization of PCB ranged from 32% up to 83%. This indicates that the test system can be a useful tool for evaluating the individual health risks arising from polluted soil or other materials.

  8. Composition of the adult digestive tract bacterial microbiome based on seven mouth surfaces, tonsils, throat and stool samples

    PubMed Central

    2012-01-01

    Background To understand the relationship between our bacterial microbiome and health, it is essential to define the microbiome in the absence of disease. The digestive tract includes diverse habitats and hosts the human body's greatest bacterial density. We describe the bacterial community composition of ten digestive tract sites from more than 200 normal adults enrolled in the Human Microbiome Project, and metagenomically determined metabolic potentials of four representative sites. Results The microbiota of these diverse habitats formed four groups based on similar community compositions: buccal mucosa, keratinized gingiva, hard palate; saliva, tongue, tonsils, throat; sub- and supra-gingival plaques; and stool. Phyla initially identified from environmental samples were detected throughout this population, primarily TM7, SR1, and Synergistetes. Genera with pathogenic members were well-represented among this disease-free cohort. Tooth-associated communities were distinct, but not entirely dissimilar, from other oral surfaces. The Porphyromonadaceae, Veillonellaceae and Lachnospiraceae families were common to all sites, but the distributions of their genera varied significantly. Most metabolic processes were distributed widely throughout the digestive tract microbiota, with variations in metagenomic abundance between body habitats. These included shifts in sugar transporter types between the supragingival plaque, other oral surfaces, and stool; hydrogen and hydrogen sulfide production were also differentially distributed. Conclusions The microbiomes of ten digestive tract sites separated into four types based on composition. A core set of metabolic pathways was present across these diverse digestive tract habitats. These data provide a critical baseline for future studies investigating local and systemic diseases affecting human health. PMID:22698087

  9. Light and scanning electron microscope examination of the digestive tract in peppered moray eel, Gymnothorax pictus (Elopomorpha).

    PubMed

    Takiue, Shunpei; Akiyoshi, Hideo

    2013-03-01

    The morphology of the digestive tract of the peppered moray eel, Gymnothorax pictus (G. pictus) (Elopomorpha: Anguilliformes) was examined using both light and scanning electron microscopy. The digestive tract is composed of the esophagus, the stomach, and the intestines; pyloric caeca were absent. The stomach was divided into a cardiac region that was continuous with the esophagus, a body which terminated in a long blind sac, and a pyloric region that was continuous with the intestine. The short intestine possessed several partitions that were created by the mucosal folds within the posterior region. The terminal region of the stomach was characterized by the thick longitudinal muscularis and subserosa, and the gastric glands and microvilli were absent. Ciliary tufts of ciliated cells were observed on the surface of the partition-like mucosal folds within the intestinal wall. Acidic mucus was secreted throughout the digestive tract. It was suggested that the terminal region of the stomach is specialized for storage of large food items. In addition, it is possible that the partition-like mucosal folds within the intestine perform a function similar to that of the spiral valve and, and along with ciliated cells, facilitated digestion and absorption. The acidic mucus likely maintained surface epithelium pH and protease activity. Within a phylogenetic context, the absence of a pyloric caeca in G. pictus while possessing an intestine implies that this species is affiliated to groups that had branched off earlier than basal teleosts. Inc.

  10. Effect of early enteral nutrition on patients with digestive tract surgery: A meta-analysis of randomized controlled trials

    PubMed Central

    Shu, Xiao-Liang; Kang, Kai; Gu, Li-Juan; Zhang, Yong-Sheng

    2016-01-01

    Postoperative early enteral nutrition (EEN) is useful for the effective recovery of patients that have undergone surgery. However, the feasibility and efficacy of EEN in patients with digestive tract surgery remain inconclusive. In the present meta-analysis, the PubMed, EMBASE, Web of Science, The Cochrane Library, China National Knowledge Infrastructure and VIP databases were searched to identify controlled trials of patients with and without EEN following digestive tract surgery between October, 1966 and December, 2014. Methodological quality assessment was carried out for each of the included studies. For estimation of the analysis indexes, relative risk (RR) was used as the effect size of the the categorical variable, while the weighted mean difference (MD) was used as the effect size of the continuous variable. The meta-analysis was conducted using RevMan 5.2 software. Eleven randomized controlled trials involving 1,095 patients were included in the meta-analysis. The results revealed that, EEN in patients with digestive tract surgery was more effective in decreasing the incidence of infectious [RR=0.50, 95% confidence interval (CI): 0.38, 0.67; P<0.01] and non-infectious complications (RR=0.72, 95% CI: 0.43, 1.22; P<0.05) and shortening the length of first bowel action (MD=−4.10, 95% CI: −5.38, −2.82; P<0.05). It also had a significant influence on increasing the serum albumin (MD=2.87, 95% CI: 1.03, 4.71; P<0.05) and serum prealbumin (MD=0.04, 95% CI: 0.02, 0.05; P<0.05) levels. In conclusion, the results of the study have shown that EEN in patients with digestive tract surgery improved the nutritional status, reduced the risk of postoperative complications, shortened the length of hospital stay and promoted the functional recovery of the digestive system. PMID:27698702

  11. Effect of early enteral nutrition on patients with digestive tract surgery: A meta-analysis of randomized controlled trials

    PubMed Central

    Shu, Xiao-Liang; Kang, Kai; Gu, Li-Juan; Zhang, Yong-Sheng

    2016-01-01

    Postoperative early enteral nutrition (EEN) is useful for the effective recovery of patients that have undergone surgery. However, the feasibility and efficacy of EEN in patients with digestive tract surgery remain inconclusive. In the present meta-analysis, the PubMed, EMBASE, Web of Science, The Cochrane Library, China National Knowledge Infrastructure and VIP databases were searched to identify controlled trials of patients with and without EEN following digestive tract surgery between October, 1966 and December, 2014. Methodological quality assessment was carried out for each of the included studies. For estimation of the analysis indexes, relative risk (RR) was used as the effect size of the the categorical variable, while the weighted mean difference (MD) was used as the effect size of the continuous variable. The meta-analysis was conducted using RevMan 5.2 software. Eleven randomized controlled trials involving 1,095 patients were included in the meta-analysis. The results revealed that, EEN in patients with digestive tract surgery was more effective in decreasing the incidence of infectious [RR=0.50, 95% confidence interval (CI): 0.38, 0.67; P<0.01] and non-infectious complications (RR=0.72, 95% CI: 0.43, 1.22; P<0.05) and shortening the length of first bowel action (MD=−4.10, 95% CI: −5.38, −2.82; P<0.05). It also had a significant influence on increasing the serum albumin (MD=2.87, 95% CI: 1.03, 4.71; P<0.05) and serum prealbumin (MD=0.04, 95% CI: 0.02, 0.05; P<0.05) levels. In conclusion, the results of the study have shown that EEN in patients with digestive tract surgery improved the nutritional status, reduced the risk of postoperative complications, shortened the length of hospital stay and promoted the functional recovery of the digestive system.

  12. Effects of Saccharomyces cerevisiae supplementation on apparent total tract digestibility of nutrients and fermentation profile in healthy horses.

    PubMed

    Mackenthun, E; Coenen, M; Vervuert, I

    2013-05-01

    Supplementation with Saccharomyces cerevisiae (SC) in horses may have some potential to modify microbial populations and thereby improve fibre digestibility. The aim of this study was to investigate the effects of SC on apparent total tract digestibility (ATTD) of nutrients, with a special focus on fibre digestion in healthy horses. The fermentation profile of microbial populations was another focus of interest. Twelve geldings were randomly assigned to three groups. The basal diet consisted of cracked corn (2 g starch/kg body weight [BW]) and hay (1.2 kg/100 kg BW). During adaptation (3 weeks) and the total faecal collection period (5 days), cracked corn was fed once daily either as control (0 g SC) or supplemented with 1 or 3 g SC (1 g SC = 2 × 10(10) colony-forming units [cfu]). There was a 4-week wash-out period between the different SC regimes. Faeces were sampled by rectal collection for the analysis of pH, nitrogen, lactic acid, short-chain fatty acids (SCFA) and SC. In faeces, mean SC cfu was significantly lower than the quantity supplemented: 0 g SC, no detection; 1 g SC, 1.1 × 10(6) cfu; 3 g SC, 3.6 × 10(6) cfu. Apparent total tract digestibility of crude fibre varied approximately 40% without any treatment-related effects. Short-chain fatty acids, lactic acids and pH in faeces were not significantly affected by SC supplementation. Saccharomyces cerevisiae supplementation was not associated with any changes in the fermentation profiles, and fibre digestion accordingly remained unchanged in intact and healthy horses. Taking into account that fibre digestion remained unchanged and recovery rate of SC in faeces was mariginal, colonization and proliferation of SC in the healthy equine intestinal tract seems to be unlikely.

  13. The effects of starvation on digestive tract function and structure in juvenile southern catfish (Silurus meridionalis Chen).

    PubMed

    Zeng, Ling-Qing; Li, Feng-Jie; Li, Xiu-Ming; Cao, Zhen-Dong; Fu, Shi-Jian; Zhang, Yao-Guang

    2012-07-01

    The size and functional capacity of the gastrointestinal (GI) tract and associated organs vary in response to environmental cues. The GI tract and associated organs are also very metabolically active in animals. Hence, animals may reduce the size and function of their GI tract to conserve energy when deprived of food. The main aims of this study were to investigate how Silurus meridionalis regulates the function and structure of its GI tract and associated organs during starvation. Starvation induced a decrease in both maintenance metabolism (MO(2rest), decreased by approximately 50%) and respiratory frequency (indicated by double side gill activity and notated as f(R), decreased by 29%). Lipase, trypsin and aminopeptidase-A showed a similar reduction in mass-specific activities during starvation, but pepsin and α-amylase did not. The starvation of experimental fish resulted in a significant reduction in body weight, the wet mass of the liver and the digestive-somatic system, the hepato-somatic index and the condition factor whereas the wet masses of the GI tract, pancreas, gall bladder and the relative intestinal length did not vary significantly during starvation. The reduction in liver wet mass was the main reason for the decrease in the wet mass of digestive-somatic system in this species. Only the mucosal area of the PI was affected significantly by starvation, decreasing by 34% at the end of the experiment. S. meridionalis displayed a decreasing intestinal mucosal area towards the distal intestine, and this gradient was not affected by starvation. The morphology and structure of both the GI tract and the liver were greatly down-regulated, as indicated by decreases in liver cell size, the mucosal thickness of the stomach and intestine, the density of goblet cells and microvilli surface area (MVSA), implying that food deprivation greatly impaired the digestive and absorptive functions of the GI tract in S. meridionalis. When deprived of food, S. meridionalis

  14. Microplastic fragments and microbeads in digestive tracts of planktivorous fish from urban coastal waters

    PubMed Central

    Tanaka, Kosuke; Takada, Hideshige

    2016-01-01

    We investigated microplastics in the digestive tracts of 64 Japanese anchovy (Engraulis japonicus) sampled in Tokyo Bay. Plastic was detected in 49 out of 64 fish (77%), with 2.3 pieces on average and up to 15 pieces per individual. All of the plastics were identified by Fourier transform infrared spectroscopy. Most were polyethylene (52.0%) or polypropylene (43.3%). Most of the plastics were fragments (86.0%), but 7.3% were beads, some of which were microbeads, similar to those found in facial cleansers. Eighty percent of the plastics ranged in size from 150 μm to 1000 μm, smaller than the reported size range of floating microplastics on the sea surface, possibly because the subsurface foraging behavior of the anchovy reflected the different size distribution of plastics between surface waters and subsurface waters. Engraulis spp. are important food for many humans and other organisms around the world. Our observations further confirm that microplastics have infiltrated the marine ecosystem, and that humans may be exposed to them. Because microplastics retain hazardous chemicals, increase in fish chemical exposure by the ingested plastics is of concern. Such exposure should be studied and compared with that in the natural diet. PMID:27686984

  15. Microplastic fragments and microbeads in digestive tracts of planktivorous fish from urban coastal waters

    NASA Astrophysics Data System (ADS)

    Tanaka, Kosuke; Takada, Hideshige

    2016-09-01

    We investigated microplastics in the digestive tracts of 64 Japanese anchovy (Engraulis japonicus) sampled in Tokyo Bay. Plastic was detected in 49 out of 64 fish (77%), with 2.3 pieces on average and up to 15 pieces per individual. All of the plastics were identified by Fourier transform infrared spectroscopy. Most were polyethylene (52.0%) or polypropylene (43.3%). Most of the plastics were fragments (86.0%), but 7.3% were beads, some of which were microbeads, similar to those found in facial cleansers. Eighty percent of the plastics ranged in size from 150 μm to 1000 μm, smaller than the reported size range of floating microplastics on the sea surface, possibly because the subsurface foraging behavior of the anchovy reflected the different size distribution of plastics between surface waters and subsurface waters. Engraulis spp. are important food for many humans and other organisms around the world. Our observations further confirm that microplastics have infiltrated the marine ecosystem, and that humans may be exposed to them. Because microplastics retain hazardous chemicals, increase in fish chemical exposure by the ingested plastics is of concern. Such exposure should be studied and compared with that in the natural diet.

  16. Preventive obesity agent montmorillonite adsorbs dietary lipids and enhances lipid excretion from the digestive tract

    PubMed Central

    Xu, Pengfei; Dai, Shu; Wang, Jing; Zhang, Jun; Liu, Jin; Wang, Fang; Zhai, Yonggong

    2016-01-01

    Western diets are typically high in fat and are associated with long-term complications such as obesity and hepatic steatosis. Because of the enjoyable taste of high-fat diets (HFDs), we are interested in determining how to decrease lipid absorption and enhance lipid excretion from the digestive tract after the consumption of eating fatty foods. Montmorillonite was initially characterized as a gastrointestinal mucosal barrier protective agent for the treatment of diarrhoea. Dietary lipid adsorbent- montmorillonite (DLA-M) was isolated and purified from Xinjiang montmorillonite clay via the water extraction method. Here, we show that DLA-M has an unexpected role in preventing obesity, hyperlipidaemia and hepatic steatosis in HFD-fed rats. Interestingly, combined application of polarized light microscopy and lipid staining analyses, showed that DLA-M crystals have dietary lipid-adsorbing ability in vitro and in vivo, which enhances lipid excretion via bowel movements. In summary, our results indicate that DLA-M prevent HFD-induced obesity. This novel dietary lipid-adsorbing agent can help prevent obesity and its comorbidities. PMID:26891902

  17. Morphology and histochemistry of the digestive tract in carnivorous freshwater Hemisorubim platyrhynchos (Siluriformes: Pimelodidae).

    PubMed

    Faccioli, Claudemir Kuhn; Chedid, Renata Alari; do Amaral, Antônio Carlos; Franceschini Vicentini, Irene Bastos; Vicentini, Carlos Alberto

    2014-09-01

    The aim of this study was to characterize the morphology and histochemistry of the digestive tract of Hemisorubim platyrhynchos, a freshwater carnivorous catfish found in Neotropical region, using gross anatomy, light microscopy and transmission electron microscopy. This species presented a short and tubular esophagus with thick longitudinal folds. The esophageal mucosa was lined by stratified squamous epithelium containing epithelial cells, club cells and also numerous goblet cells, which secreted acidic and neutral mucins to protect and lubricate the epithelium. The stomach was a J-shaped saccular organ consisting of the cardiac, fundic and pyloric regions. The cardiac and fundic regions contained tubular gastric glands, whereas these glands were absent in the pyloric region. The gastric epithelial cells presented apical secretions that predominantly consisted of neutral mucins. The gastric musculature was, therefore, likely designed for retaining prey and the mechanical preparation of food. The intestine consisted of four regions: anterior, middle, posterior and rectal. The anterior intestine possessed thick folds to increase the surface area for absorption, the middle intestine was coiled and the posterior intestine presented thin folds and a thick musculature. The intestinal epithelium consisted mainly of enterocytes and goblet cells. Enterocytes were columnar cells with a PAS-positive brush border that contained lysosomes in the posterior intestine. Goblet cells were more numerous in the posterior intestine and secreted acidic and neutral mucins important for lubricating and protecting the epithelium. The rectum was lined by columnar epithelium with goblet cells and epithelial cells containing apical acidic and neutral mucins.

  18. Normal yeast flora of the upper digestive tract of some wild columbids

    USGS Publications Warehouse

    Kocan, R.M.; Hasenclever, H.F.

    1972-01-01

    Seven species of pigeons and doves were cultured for yeasts in the upper digestive tract. The following list gives the isolation rate for each columbid species and the yeasts cultured from them: feral pigeon Columba Livia (Gmelin) 95% -Candida albicans (Robin) Berkhout, C. tropicalis (Castellani) Berkhout, C. krusei (Cast.) Berkhout, C. guilliermondii (Cast.) Langeron et Guerra, Torulopsis glabrata (Anderson) Lodder et De Vries, Saccharomyces telluris Van der Walt, and Geotrichum sp.; white-crowned pigeon (C. leucocephala Linnaeus) 56% -- S. telluris; mourning dove (Zenaidura rnacroura Linnaeus) 24% -- C. albicans, C. tropicalis, C. guilliermondii, and Geotrichurn sp.; passerine ground dove (Collumbigallina passerina Linnaeus) 20% -- C. parapsilosis (Ashford) Langeron et Talice, Kloeckera apiculata (Reess Emend. Klocker) Janke; zenaida dove (Zenaida aurita Temminck) 16% -- C. albicans, C. guilliermondii, and T. glabrata; one moustasche dove (Geotrygon mystacea Gosse) -- C. guillierrnondii; ringed turtle dove (Streptopelia rizoria Linnaeus) 14% -- C. albicans and Geotrichurn sp. No signs of disease could be seen in the 139 birds that were examined, and it was concluded that these yeasts comprise a part of the columbid's normal microbial flora.

  19. Lactobacillus casei Low-Temperature, Dairy-Associated Proteome Promotes Persistence in the Mammalian Digestive Tract.

    PubMed

    Lee, Bokyung; Tachon, Sybille; Eigenheer, Richard A; Phinney, Brett S; Marco, Maria L

    2015-08-01

    We found that incubation of probiotic Lactobacillus casei BL23 in milk at 4 °C prior to ingestion increased its survival in the mammalian digestive tract. To investigate the specific molecular adaptations of L. casei to milk, we used tandem mass spectrometry to compare proteins produced by L. casei BL23 at 4 °C in milk to those in exponential and stationary phase cells in laboratory culture medium at either 37 or 4 °C. These comparisons revealed a core of expressed L. casei proteins as well as proteins produced in either a growth-phase or temperature-specific manner. In total, 205 L. casei proteins were uniquely expressed or detected in higher abundance specifically as a result of incubation in milk and included an over-representation of proteins for cell surface modification, fatty acid metabolism, amino acid transport and metabolism, and inorganic ion transport. Genes for DltD (d-alanine transfer protein), FabH (3-oxoacyl-ACP synthase), RecA (recombinase A), and Sod (superoxide dismutase) were targeted for inactivation. The competitive fitness of the mutants was altered in the mouse intestine compared with wild-type cells. These results show that the food matrix can have a profound influence on dietary (probiotic) bacteria and their functional significance in the mammalian gut. PMID:26148687

  20. Correlating diet and digestive tract specialization: examples from the lizard family Liolaemidae.

    PubMed

    O'Grady, Shannon P; Morando, Mariana; Avila, Luciano; Dearing, M Denise

    2005-01-01

    A range of digestive tract specializations were compared among dietary categories in the family Liolaemidae to test the hypothesis that herbivores require greater gut complexity to process plant matter. Additionally, the hypothesis that herbivory favors the evolution of larger body size was tested. Lastly, the association between diet and hindgut nematodes was explored. Herbivorous liolaemids were larger relative to omnivorous and insectivorous congeners and consequently had larger guts. In addition, small intestine length of herbivorous liolaemids was disproportionately longer than that of congeners. Significant interaction effects between diet and body size among organ dimensions indicate that increases in organ size occur to a greater extent in herbivores than other diet categories. For species with plant matter in their guts, there was a significant positive correlation between the percentage of plant matter consumed and small intestine length. Herbivorous liolaemids examined in this study lacked the gross morphological specializations (cecum and colonic valves) found in herbivores in the families Iguanidae and Agamidae. A significantly greater percentage of herbivorous species had nematodes in their gut. Of the species with nematodes, over 95% of herbivores had nematodes only in the hindgut. Prevalence of nematodes in the hindgut of herbivores was 2 x that of omnivores and 4 x that of insectivores.

  1. [Management of treatment in patients with neuroendocrine neoplasmas of digestive tract].

    PubMed

    Kinová, Sona; Kovácová, Martina; Caprnda, Martin; Koren, Michal

    2015-12-01

    Neuroendocrine neoplasmas are a form of cancer arising from cells of diffuse neuroendocrine system. They produce peptides or amines that act as hormones or neurotransmitters. Incidence of NENs is relatively low. Diagnostic work-up and treatment requires a multidisciplinary team approach. The aim of this study was an analysis of data from patients with well-differentiated neuroendocrine neoplasmas of gastrointestinal tract. The study included patients followed up from 1998 to 2013 with histologically confirmed well-differentiated digestive neuroendocrine neoplasm with low or intermediate malignant potential. 97 patients were included; 34 men (35.1%) and 63 women (64.9%). In patients being diagnosed after 2005 interferon treatment is significantly less used than endoscopic and peptide receptor radionuclide therapy. We have identified more appropriate discriminant values of 5-HIAA and chromogranin A (6.8 mg/24 hours; 70 ng/ml) for predicting the presence of metastases at the time of diagnosis. We have identified following risk factors for overall mortality: liver metastases, presence of diarrhea, flush, small bowel primary tumor, high values of CgA and 5-HIAA at the time of diagnosis (5-HIAA > 520.52 mg/24 hours, CgA > 174.5 ng/ml). Surgical treatment was found to be a positive prognostic factor. PMID:27124967

  2. Molecular mechanisms for thyroid hormone-induced remodeling in the amphibian digestive tract: a model for studying organ regeneration.

    PubMed

    Ishizuya-Oka, Atsuko; Shi, Yun-Bo

    2005-12-01

    During amphibian metamorphosis the digestive tract is extensively remodeled under the control of epithelial-connective tissue interactions. At the cellular level, larval epithelial cells undergo apoptosis, while a small number of stem cells appear, actively proliferate, and then differentiate to form adult epithelium that is analogous to its mammalian counterpart. Therefore the amphibian digestive tract is a unique model system for the study of postembryonic organ regeneration. As amphibian intestinal remodeling can be triggered by thyroid hormone (TH), the molecular mechanisms involved can be studied from the perspective of examining the expression cascade of TH response genes. A number of these genes have been isolated from the intestine of Xenopus laevis. Recent progress in the functional analysis of this cascade has shed light on key molecules in intestinal remodeling such as matrix metalloproteinase-11, sonic hedgehog, and bone morphogenetic protein-4. These genes are also thought to play key roles in organogenesis and/or homeostasis in both chick and mammalian digestive tract, suggesting the existence of conserved mechanisms underlying such events in terrestrial vertebrates. In this article, we review our recent findings in this field, focusing on the development of adult epithelium in the X. laevis intestine.

  3. Atypical microbial infections of digestive tract may contribute to diarrhea in mucopolysaccharidosis patients: a MPS I case study

    PubMed Central

    Węgrzyn, Grzegorz; Kurlenda, Julianna; Liberek, Anna; Tylki-Szymańska, Anna; Czartoryska, Barbara; Piotrowska, Ewa; Jakóbkiewicz-Banecka, Joanna; Węgrzyn, Alicja

    2005-01-01

    Background Mucopolysaccharidoses are heritable, metabolic diseases caused by deficiency in an activity of one of specific lysosomal enzymes involved in degradation of mucoplysaccharides (glycosaminoglycans). Among many medical problems of patients with mucopolysaccharidoses, there are frequent episodes of diarrhea of unknown etiology. Case presentation A girl, diagnosed enzymatically for mucopolysaccharidosis type I (deficiency of α-L-iduronidase) at the age of 3 years and 9 months, was investigated until the age of 5 years and 4 months. Frequent loose stools and episodes of diarrhea, often accompanied by vomiting, were encountered. Detailed microbiological analyses were performed and atypical microbial infections (most often enetropathogenic Escherichia coli, but also other species, like Pseudomonas aeruginosa or Staphylococcus aureus, as well as adenoviruses) of the digestive tract were found in most severe diarrhea episodes. Often, isolations of pathogenic bacterial strains from stools of the investigated patient suffering from diarrhea were not obvious during the first screening, and only detailed microbiological studies, including re-isolation of colonies, gave the results of isolation of particular pathogenic strains (especially in the case of enetropathogenic E. coli). Conclusion We conclude that atypical microbial infections of digestive tract may contribute significantly to diarrhea in mucopolysaccaridosis patients. Since isolated strains were not typical and their isolation was often possible only after detailed investigation (not during a standard screening), such atypical microbial infections of digestive tract of mucopolysaccharidosis patients could be usually overlooked to date. Importantly, these atypical infections could be effectively treated with antimicrobial agents. PMID:15882450

  4. Measurement of true ileal digestibility and total tract retention of phosphorus in corn and canola meal for broiler chickens.

    PubMed

    Mutucumarana, R K; Ravindran, V; Ravindran, G; Cowieson, A J

    2014-02-01

    The study reported herein was conducted to determine and compare the nonphytate P, digestible P, and retainable P contents of corn and canola meal for broiler chickens. Four semipurified diets were formulated from each of ingredient to contain graded concentrations of nonphytate P. The experiment was conducted as a randomized complete block design with 4 weight blocks of 8 cages each (6 birds per cage). A total of 192 broilers (Ross 308), 21 d old, were assigned to the 8 test diets. Ileal digestibility and total tract retention coefficients of P were determined by the indicator and total collection methods, respectively, and linear regression method was used to determine the true P digestibility and true P retention coefficients. The apparent ileal digestibility of P in corn was influenced (quadratic, P < 0.05) by increasing dietary nonphytate P concentrations, whereas P retention was unaffected (P > 0.05). The apparent ileal P digestibility in broilers fed diets based on canola meal was similar (P > 0.05) at different P concentrations. Phosphorus retention in broilers fed diets based on canola meal (linear, P < 0.01) decreased with increasing P concentrations. True ileal P digestibility and true P retention coefficients of corn were determined to be 0.676 and 0.632, respectively. The corresponding values for canola meal were 0.469 and 0.486, respectively. In both ingredients, the determined true ileal digestibility and total tract retention coefficients were not different (P > 0.05). Total P, nonphytate P, true digestible P, and true retainable P contents of corn were determined to be 2.5, 0.8, 1.7, and 1.6 g/kg (as received), respectively. The corresponding values for canola meal were 9.7, 2.8, 4.6, and 4.7 g/kg (as received), respectively. The present data demonstrated that the regression method can be successfully used to measure true P digestibility of low and high P feed ingredients and that both true ileal digestibility and retention coefficients are

  5. Association between Changing Mortality of Digestive Tract Cancers and Water Pollution: A Case Study in the Huai River Basin, China

    PubMed Central

    Ren, Hongyan; Wan, Xia; Yang, Fei; Shi, Xiaoming; Xu, Jianwei; Zhuang, Dafang; Yang, Gonghuan

    2014-01-01

    The relationship between the ever-increasing cancer mortality and water pollution is an important public concern in China. This study aimed to explore the association between serious water pollution and increasing digestive cancer mortality in the Huai River Basin (HRB) in China. A series of frequency of serious pollution (FSP) indices including water quality grade (FSPWQG), biochemical oxygen demand (FSPBOD), chemical oxygen demand (FSPCOD), and ammonia nitrogen (FSPAN) were used to characterize the surface water quality between 1997 and 2006. Data on the county-level changing mortality (CM) due to digestive tract cancers between 1975 and 2006 were collected for 14 counties in the study area. Most of investigated counties (eight) with high FSPWQG (>50%) distributed in the northern region of the HRB and had larger CMs of digestive tract cancers. In addition to their similar spatial distribution, significant correlations between FSP indices and CMs were observed by controlling for drinking water safety (DWS), gross domestic product (GDP), and population (POP). Furthermore, the above-mentioned partial correlations were clearly increased when only controlling for GDP and POP. Our study indicated that county-level variations of digestive cancer mortality are remarkably associated with water pollution, and suggested that continuous measures for improving surface water quality and DWS and hygienic interventions should be effectively implemented by local governments. PMID:25546281

  6. Association between changing mortality of digestive tract cancers and water pollution: a case study in the Huai River Basin, China.

    PubMed

    Ren, Hongyan; Wan, Xia; Yang, Fei; Shi, Xiaoming; Xu, Jianwei; Zhuang, Dafang; Yang, Gonghuan

    2015-01-01

    The relationship between the ever-increasing cancer mortality and water pollution is an important public concern in China. This study aimed to explore the association between serious water pollution and increasing digestive cancer mortality in the Huai River Basin (HRB) in China. A series of frequency of serious pollution (FSP) indices including water quality grade (FSPWQG), biochemical oxygen demand (FSPBOD), chemical oxygen demand (FSPCOD), and ammonia nitrogen (FSPAN) were used to characterize the surface water quality between 1997 and 2006. Data on the county-level changing mortality (CM) due to digestive tract cancers between 1975 and 2006 were collected for 14 counties in the study area. Most of investigated counties (eight) with high FSPWQG (>50%) distributed in the northern region of the HRB and had larger CMs of digestive tract cancers. In addition to their similar spatial distribution, significant correlations between FSP indices and CMs were observed by controlling for drinking water safety (DWS), gross domestic product (GDP), and population (POP). Furthermore, the above-mentioned partial correlations were clearly increased when only controlling for GDP and POP. Our study indicated that county-level variations of digestive cancer mortality are remarkably associated with water pollution, and suggested that continuous measures for improving surface water quality and DWS and hygienic interventions should be effectively implemented by local governments.

  7. Examination of digestive enzyme distribution in gut tract and functions of intestinal caecum, in megascolecid earthworms (Oligochaeta: Megascolecidae) in Japan.

    PubMed

    Nozaki, Mana; Ito, Katsutoshi; Miura, Chiemi; Miura, Takeshi

    2013-09-01

    Earthworms ingest various materials in addition to food items, such as soil particles. Most earthworms of the family Megascolecidae, a dominant family in Japan, have intestinal caeca connected directly to the intestinal tract. The function of the caeca has not been demonstrated, although it is thought to be associated with digestion. We investigated the activity of the digestive enzymes amylase, phosphatase, cellulase, and protease in different regions of the gut, including the intestinal caeca, in three species of megascolecid earthworms, Pheretima heteropoda, Pheretima hilgendorfi, and Pheretima sieboldi. Activities of several enzymes were high in the intestinal caeca; in particular, protease activity was higher in the caeca than that in the anterior gut, foregut, midgut, and hindgut in all three species. Moreover, the ratio of enzyme activities in the intestinal caeca to whole-gut tended to be higher in manicate intestinal caeca than in simple intestinal caeca. These results suggest that the digestive system of earthworms relies on the intestinal caeca.

  8. Digestive diseases

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/007447.htm Digestive diseases To use the sharing features on this page, please enable JavaScript. Digestive diseases are disorders of the digestive tract, which ...

  9. Lactobacillus bombi sp. nov., from the digestive tract of laboratory-reared bumblebee queens (Bombus terrestris).

    PubMed

    Killer, J; Votavová, A; Valterová, I; Vlková, E; Rada, V; Hroncová, Z

    2014-08-01

    Three bacterial strains belonging to the genus Lactobacillus were isolated from the digestive tracts of laboratory-reared bumblebee queens (Bombus terrestris) using MRS agar under anaerobic conditions. The isolates were identified according to 16S rRNA gene sequence analysis as undescribed members of the genus Lactobacillus, with the highest 16S rRNA gene sequence similarity (96.9 %) to the uncharacterized bacterial strain Lactobacillus sp. Mboho2r2 isolated from the stomach of a European honeybee (Apis mellifera). Lactobacillus tucceti was found to be the closest related species with a validly published name, with 92.9 % 16S rRNA gene sequence similarity to the type strain. However, phylogenetic analyses based on different markers revealed that this species is phylogenetically very distant from the novel strains. The DNA G+C content of the proposed type strain BTLCH M1/2(T) is 37.8 mol%. The fatty acids C(19 : 1)ω6c and/or C(19 : 0) cyclo ω10c/19ω6, C(18 : 1)ω9c and C(16 : 0) were predominant in all strains. Diphosphatidylglycerol, phosphatidylglycerol, a phospholipid, seven glycolipids and two phosphoglycolipids were detected in the novel strains. Growth was observed at 47 °C. The peptidoglycan type A4α L-Lys-D-Asp was determined for strain BTLCH M1/2(T). Genotypic characteristics and phylogenetic analyses based on the phylogenetic markers hsp60, pheS, rpoA and tuf as well as phenotypic characteristics and the results of chemotaxonomic analyses confirmed that the new isolates belong to a novel species of the genus Lactobacillus, for which the name Lactobacillus bombi sp. nov. is proposed. The type strain is BTLCH M1/2(T) ( = DSM 26517(T) = CCM 8440(T)). PMID:24824637

  10. SIMPLIFIED TECHNIQUE FOR RECONSTRUCTION OF THE DIGESTIVE TRACT AFTER TOTAL AND SUBTOTAL GASTRECTOMY FOR GASTRIC CANCER

    PubMed Central

    ZILBERSTEIN, Bruno; JACOB, Carlos Eduardo; BARCHI, Leandro Cardoso; YAGI, Osmar Kenji; RIBEIRO-JR, Ulysses; COIMBRA, Brian Guilherme Monteiro Marta; CECCONELLO, Ivan

    2014-01-01

    Background Laparoscopic surgery has been increasingly applied to gastric cancer surgery. Gastrointestinal tract reconstruction totally done by laparoscopy also has been a challenge for those who developed this procedure. Aim To describe simplified reconstruction after total or subtotal gastrectomy for gastric cancer by laparoscopy and the results of its application in a series of cases. Methods In the last four years, 75 patients were operated with gastric cancer and two with GIST. Thirty-four were women and 43 men. The age ranged from 38 to 77 years with an average of 55 years. In two patients with GIST a total and a subtotal gastrectomy were performed. In the other 75 patients were done 21 total gastrectomies and 54 subtotal. In all cancers, gastrectomy with D2 lymphadenectomy was completed with at least 37 lymph nodes removed. Was used in these operations a modified laparoscopic technique proposed by the authors consisting in a latero lateral esophagojejunal anastomosis with linear stapler in TG as well in STG, and reconstruction of the digestive continuity also in the upper abdomen. Results The intraoperative and immediate postoperative course were uneventful, except for one case of bleeding due to an opening clip, necessitating re-intervention. The operative time was 300 minutes, with no difference between total or subtotal gastrectomy. The number of lymph nodes removed varied from 28 to 69, averaging 37. Postoperative staging showed one case in T4 N2 M0; 13 in T2 N0 MO; 27 in T2 N1 M0; 24 in T3 N1 M0 and 10 in T3 N2 M0. Complication in only one case was observed on the 10th postoperative day with a small anastomotic leakage in esophagojejunal anastomose with spontaneous closure. Conclusion The patient's evolution with no complications, no mortality and just one small anastomotic leakage with no systemic repercussions is a strong indication of the liability and feasibility of this innovative technical method. PMID:25004292

  11. Lactobacillus bombi sp. nov., from the digestive tract of laboratory-reared bumblebee queens (Bombus terrestris).

    PubMed

    Killer, J; Votavová, A; Valterová, I; Vlková, E; Rada, V; Hroncová, Z

    2014-08-01

    Three bacterial strains belonging to the genus Lactobacillus were isolated from the digestive tracts of laboratory-reared bumblebee queens (Bombus terrestris) using MRS agar under anaerobic conditions. The isolates were identified according to 16S rRNA gene sequence analysis as undescribed members of the genus Lactobacillus, with the highest 16S rRNA gene sequence similarity (96.9 %) to the uncharacterized bacterial strain Lactobacillus sp. Mboho2r2 isolated from the stomach of a European honeybee (Apis mellifera). Lactobacillus tucceti was found to be the closest related species with a validly published name, with 92.9 % 16S rRNA gene sequence similarity to the type strain. However, phylogenetic analyses based on different markers revealed that this species is phylogenetically very distant from the novel strains. The DNA G+C content of the proposed type strain BTLCH M1/2(T) is 37.8 mol%. The fatty acids C(19 : 1)ω6c and/or C(19 : 0) cyclo ω10c/19ω6, C(18 : 1)ω9c and C(16 : 0) were predominant in all strains. Diphosphatidylglycerol, phosphatidylglycerol, a phospholipid, seven glycolipids and two phosphoglycolipids were detected in the novel strains. Growth was observed at 47 °C. The peptidoglycan type A4α L-Lys-D-Asp was determined for strain BTLCH M1/2(T). Genotypic characteristics and phylogenetic analyses based on the phylogenetic markers hsp60, pheS, rpoA and tuf as well as phenotypic characteristics and the results of chemotaxonomic analyses confirmed that the new isolates belong to a novel species of the genus Lactobacillus, for which the name Lactobacillus bombi sp. nov. is proposed. The type strain is BTLCH M1/2(T) ( = DSM 26517(T) = CCM 8440(T)).

  12. Effect of Antimicrobial Consumption and Production Type on Antibacterial Resistance in the Bovine Respiratory and Digestive Tract.

    PubMed

    Catry, Boudewijn; Dewulf, Jeroen; Maes, Dominiek; Pardon, Bart; Callens, Benedicte; Vanrobaeys, Mia; Opsomer, Geert; de Kruif, Aart; Haesebrouck, Freddy

    2016-01-01

    The aim of this study was to investigate the relationship between antimicrobial use and the occurrence of antimicrobial resistance in the digestive and respiratory tract in three different production systems of food producing animals. A longitudinal study was set up in 25 Belgian bovine herds (10 dairy, 10 beef, and 5 veal herds) for a 2 year monitoring of antimicrobial susceptibilities in E. coli and Pasteurellaceae retrieved from the rectum and the nasal cavity, respectively. During the first year of observation, the antimicrobial use was prospectively recorded on 15 of these farms (5 of each production type) and transformed into the treatment incidences according to the (animal) defined daily dose (TIADD) and (actually) used daily dose (TIUDD). Antimicrobial resistance rates of 4,174 E. coli (all herds) and 474 Pasteurellaceae (beef and veal herds only) isolates for 12 antimicrobial agents demonstrated large differences between intensively reared veal calves (abundant and inconstant) and more extensively reared dairy and beef cattle (sparse and relatively stable). Using linear mixed effect models, a strong relation was found between antimicrobial treatment incidences and resistance profiles of 1,639 E. coli strains (p<0.0001) and 309 Pasteurellaceae (p≤0.012). These results indicate that a high antimicrobial selection pressure, here found to be represented by low dosages of oral prophylactic and therapeutic group medication, converts not only the commensal microbiota from the digestive tract but also the opportunistic pathogenic bacteria in the respiratory tract into reservoirs of multi-resistance. PMID:26820134

  13. Effect of Antimicrobial Consumption and Production Type on Antibacterial Resistance in the Bovine Respiratory and Digestive Tract

    PubMed Central

    Catry, Boudewijn; Dewulf, Jeroen; Maes, Dominiek; Pardon, Bart; Callens, Benedicte; Vanrobaeys, Mia; Opsomer, Geert; de Kruif, Aart; Haesebrouck, Freddy

    2016-01-01

    The aim of this study was to investigate the relationship between antimicrobial use and the occurrence of antimicrobial resistance in the digestive and respiratory tract in three different production systems of food producing animals. A longitudinal study was set up in 25 Belgian bovine herds (10 dairy, 10 beef, and 5 veal herds) for a 2 year monitoring of antimicrobial susceptibilities in E. coli and Pasteurellaceae retrieved from the rectum and the nasal cavity, respectively. During the first year of observation, the antimicrobial use was prospectively recorded on 15 of these farms (5 of each production type) and transformed into the treatment incidences according to the (animal) defined daily dose (TIADD) and (actually) used daily dose (TIUDD). Antimicrobial resistance rates of 4,174 E. coli (all herds) and 474 Pasteurellaceae (beef and veal herds only) isolates for 12 antimicrobial agents demonstrated large differences between intensively reared veal calves (abundant and inconstant) and more extensively reared dairy and beef cattle (sparse and relatively stable). Using linear mixed effect models, a strong relation was found between antimicrobial treatment incidences and resistance profiles of 1,639 E. coli strains (p<0.0001) and 309 Pasteurellaceae (p≤0.012). These results indicate that a high antimicrobial selection pressure, here found to be represented by low dosages of oral prophylactic and therapeutic group medication, converts not only the commensal microbiota from the digestive tract but also the opportunistic pathogenic bacteria in the respiratory tract into reservoirs of multi-resistance. PMID:26820134

  14. Effect of Antimicrobial Consumption and Production Type on Antibacterial Resistance in the Bovine Respiratory and Digestive Tract.

    PubMed

    Catry, Boudewijn; Dewulf, Jeroen; Maes, Dominiek; Pardon, Bart; Callens, Benedicte; Vanrobaeys, Mia; Opsomer, Geert; de Kruif, Aart; Haesebrouck, Freddy

    2016-01-01

    The aim of this study was to investigate the relationship between antimicrobial use and the occurrence of antimicrobial resistance in the digestive and respiratory tract in three different production systems of food producing animals. A longitudinal study was set up in 25 Belgian bovine herds (10 dairy, 10 beef, and 5 veal herds) for a 2 year monitoring of antimicrobial susceptibilities in E. coli and Pasteurellaceae retrieved from the rectum and the nasal cavity, respectively. During the first year of observation, the antimicrobial use was prospectively recorded on 15 of these farms (5 of each production type) and transformed into the treatment incidences according to the (animal) defined daily dose (TIADD) and (actually) used daily dose (TIUDD). Antimicrobial resistance rates of 4,174 E. coli (all herds) and 474 Pasteurellaceae (beef and veal herds only) isolates for 12 antimicrobial agents demonstrated large differences between intensively reared veal calves (abundant and inconstant) and more extensively reared dairy and beef cattle (sparse and relatively stable). Using linear mixed effect models, a strong relation was found between antimicrobial treatment incidences and resistance profiles of 1,639 E. coli strains (p<0.0001) and 309 Pasteurellaceae (p≤0.012). These results indicate that a high antimicrobial selection pressure, here found to be represented by low dosages of oral prophylactic and therapeutic group medication, converts not only the commensal microbiota from the digestive tract but also the opportunistic pathogenic bacteria in the respiratory tract into reservoirs of multi-resistance.

  15. Ontogeny of the digestive tract and enzymes in rock bream Oplegnathus fasciatus (Temminck et Schlegel 1844) larvae.

    PubMed

    He, Tao; Xiao, Zhizhong; Liu, Qinghua; Ma, Daoyuan; Xu, Shihong; Xiao, Yongshuang; Li, Jun

    2012-04-01

    Histological development of the digestive tract and specific activities of three digestive enzymes (trypsin, alkaline phosphatase, and pepsin) were studied in rock bream Oplegnathus fasciatus from hatching to 50 days after hatching (DAH). At hatching, the digestive tract appeared as an undifferentiated straight tube and differentiated into the buccopharynx, esophagus, stomach, intestine, and rectum at mouth opening by 3 DAH. The taste bud and mandibular teeth were present in the buccopharyx at 8 DAH. The goblet cells appeared in the esophagus at 8 DAH and in the buccopharyx at 9 DAH. The stomach anlage was formed at 2 DAH and developed into cardia, fundus, and pylorus at 14 DAH. The gastric glands were visible at 16 DAH, and the pepsin was firstly detected on 22 DAH. At 2 DAH, the intestinal valve appeared and divided the intestine into anterior intestine (AI) and posterior intestine (PI). The rectum was differentiated from the PI at 3 DAH. The supranuclear vacuoles were visible in the rectum by 6 DAH, and the lipid inclusions were present in the AI at 8 DAH. The alkaline phosphatase was detected at 1 DAH, and the increase in its activity indicated the maturation of the intestine after 40 DAH. The hepatocytes and pancreatic cells were differentiated from the blast cells at 2 DAH, and the acidophilic zymogen granules in the exocrine pancreas were observed simultaneously. The trypsin was detected by 1 DAH and increased to the maximum at 19 DAH, followed by a decrease as the stomach became functional.

  16. Insights into bread melanoidins: fate in the upper digestive tract and impact on the gut microbiota using in vitro systems.

    PubMed

    Helou, Cynthia; Denis, Sylvain; Spatz, Madeleine; Marier, David; Rame, Véronique; Alric, Monique; Tessier, Frédéric J; Gadonna-Widehem, Pascale

    2015-12-01

    Bread melanoidins are heterogeneous, nitrogen-containing, brown macromolecules generated during the last stages of the Maillard reaction in bread. The aim of this study was to investigate the impact and fate of these bread melanoidins in the human gastrointestinal tract using in vitro systems. Batch systems as well as the TNO gastrointestinal tract were used for studying the digestion of various bread samples. These samples included bread crumb, bread crust and two bread-crust-simulating models: a fiber-free model (gluten, starch and glucose heated together) and its control, free of Maillard reaction products (gluten heated separately than starch and glucose). Furthermore, the impact of these two bread-crust-simulating models on the gut microbiota was assessed using a static anaerobic batch system. Bread melanoidins from bread crust and its model were shown to be partially digested by amylases and proteases, suggesting that these melanoidins have peptidic as well as glycosidic bonds in their skeleton. The impact of bread melanoidins from the bread-crust-simulating models and their digestion products on the gut microbiota revealed an individual-dependent response for most flora except for enterobacteria. This flora decreased by -22%, -48% & -100% depending on the individual. Thus, bread melanoidins seem to exert an anti-inflammatory effect by inhibiting enterobacteria. PMID:26364594

  17. Culture-independent characterization of the digestive-tract microbiota of the medicinal leech reveals a tripartite symbiosis.

    PubMed

    Worthen, Paul L; Gode, Cindy J; Graf, Joerg

    2006-07-01

    Culture-based studies of the microbial community within the gut of the medicinal leech have typically been focused on various Aeromonas species, which were believed to be the sole symbiont of the leech digestive tract. In this study, analysis of 16S rRNA gene clone libraries confirmed the presence of Aeromonas veronii and revealed a second symbiont, clone PW3, a novel member of the Rikenellaceae, within the crop, a large compartment where ingested blood is stored prior to digestion. The diversity of the bacterial community in the leech intestinum was determined, and additional symbionts were detected, including members of the alpha-, gamma-, and delta-Proteobacteria, Fusobacteria, Firmicutes, and Bacteroidetes. The relative abundances of the clones suggested that A. veronii and the novel clone, PW3, also dominate the intestinum community, while other clones, representing transient organisms, were typically present in low numbers. The identities of these transients varied greatly between individual leeches. Neither time after feeding nor feeding on defibrinated blood caused a change in identity of the dominant members of the microbial communities. Terminal restriction fragment length polymorphism analysis was used to verify that the results from the clone libraries were representative of a larger data set. The presence of a two-member bacterial community in the crop provides a unique opportunity to investigate both symbiont-symbiont and symbiont-host interactions in a natural model of digestive-tract associations.

  18. Health Effects of Alkaline Diet and Water, Reduction of Digestive-tract Bacterial Load, and Earthing.

    PubMed

    Mousa, Haider Abdul-Lateef

    2016-04-01

    In the article, the author discusses the issue of chronic, low-grade acidosis that is thought to be brought about primarily by 2 factors: (1) advancing age, with a consequent decline in renal function; and (2) diet. An acid-forming diet can induce low-grade metabolic acidosis, which causes very small decreases in blood pH and plasma bicarbonate (HCO3-) that remain within the range considered to be normal. However, if the duration of the acidosis is prolonged or chronically present, even a low degree of acidosis can become significant. This article reviews supporting evidence in the literature that has shown that consumption of abundant alkaline-forming foods can result in improvement in bone mineral density (BMD) and muscle mass, protection from chronic illnesses, reduced tumor-cell invasion and metastasis, and effective excretion of toxins from the body. In addition, a large number of studies showing the benefits of alkaline water (mineral water) have revealed that people consuming water with a high level of total dissolved solids (TDS) (ie, with a high mineral content) have shown a lower incidence of coronary heart disease (CHD), cardiovascular disease (CVD), and cancer and lower total mortality rates. Consumption of alkaline water also may prevent osteoporosis and protect pancreatic beta cells with its antioxidant effects. In addition, this article discusses the literature that shows that reducing digestive-tract bacterial load can play an important role in increasing blood alkalinity toward the normal upper limit. That change occurs through good oral hygiene, flossing of teeth, perfect chewing of food, and bowel evacuation as soon as possible. Finally, the author reviews the literature that shows that earthing (ie, the direct contact of the human body with the earth) can supply a current of plentiful electrons. Earthing has been shown to reduce acute and chronic inflammation, blood glucose in patients with diabetes, red blood cell (RBC) aggregation, and blood

  19. Health Effects of Alkaline Diet and Water, Reduction of Digestive-tract Bacterial Load, and Earthing.

    PubMed

    Mousa, Haider Abdul-Lateef

    2016-04-01

    In the article, the author discusses the issue of chronic, low-grade acidosis that is thought to be brought about primarily by 2 factors: (1) advancing age, with a consequent decline in renal function; and (2) diet. An acid-forming diet can induce low-grade metabolic acidosis, which causes very small decreases in blood pH and plasma bicarbonate (HCO3-) that remain within the range considered to be normal. However, if the duration of the acidosis is prolonged or chronically present, even a low degree of acidosis can become significant. This article reviews supporting evidence in the literature that has shown that consumption of abundant alkaline-forming foods can result in improvement in bone mineral density (BMD) and muscle mass, protection from chronic illnesses, reduced tumor-cell invasion and metastasis, and effective excretion of toxins from the body. In addition, a large number of studies showing the benefits of alkaline water (mineral water) have revealed that people consuming water with a high level of total dissolved solids (TDS) (ie, with a high mineral content) have shown a lower incidence of coronary heart disease (CHD), cardiovascular disease (CVD), and cancer and lower total mortality rates. Consumption of alkaline water also may prevent osteoporosis and protect pancreatic beta cells with its antioxidant effects. In addition, this article discusses the literature that shows that reducing digestive-tract bacterial load can play an important role in increasing blood alkalinity toward the normal upper limit. That change occurs through good oral hygiene, flossing of teeth, perfect chewing of food, and bowel evacuation as soon as possible. Finally, the author reviews the literature that shows that earthing (ie, the direct contact of the human body with the earth) can supply a current of plentiful electrons. Earthing has been shown to reduce acute and chronic inflammation, blood glucose in patients with diabetes, red blood cell (RBC) aggregation, and blood

  20. Validation of an approach to predict total-tract fiber digestibility using a standardized in vitro technique for different diets fed to high-producing dairy cows.

    PubMed

    Lopes, F; Ruh, K; Combs, D K

    2015-04-01

    The experimental objective was to validate an in vitro model to predict total-tract neutral detergent fiber (NDF) digestibility in dairy cattle. Twenty-one diets from 7 studies conducted at University of Wisconsin-Madison were analyzed for in vitro fiber digestibility. Forages varied among diets (corn, alfalfa, tall and meadow fescue, and wheat straw silages) and nutrient composition (ranges: NDF = 22.5 to 33.8%; crude protein = 15.8 to 18.9%; nonfiber carbohydrates = 38.0 to 51.0%). Total-tract NDF digestibility (TTNDFD) observed in in vivo trials was determined using different markers as described in the individual studies. The in vitro TTNDFD model predicted total-tract fiber digestibility from the proportion of total NDF potentially digestible (pdNDF), rate of pdNDF degradation, and rate of passage of pdNDF. The model predicted TTNDFD similar to in vivo measurements. The relationship between TTNDFD measured in vivo and TTNDFD predicted by the in vitro assay was significant (R(2) = 0.68). The relationship between in vitro 30-h NDF digestibility values and in vivo total-tract NDF digestibility values was not significant, whereas in vitro 48-h NDF digestibility values were correlated (R(2) = 0.30) with in vivo TTNDFD measurements. Indigestible NDF (iNDF) showed a negative relationship (R(2) = 0.40) with TTNDFD in vivo. Each 1-percentage-unit increase of iNDF resulted in a decrease of 0.96 percentage units of total-tract NDF digestibility; however, iNDF by itself was not a good predictor of TTNDFD because of the difference among the means. This study showed that an in vitro TTNDFD model that uses iNDF, pdNDF, and rates of pdNDF digestion and passage can predict (R(2) = 0.68) total-tract NDF digestibility. Most importantly, we demonstrated the ability to predict total-tract fiber digestibility from a model based on in vitro NDF degradation, which could improve our ability to optimize forage utilization and milk production.

  1. [Reduction of plant fibers in the digestive tract of two pika species (Ochotona pallasi and O. dauurica, Lagomorpha, Ochotonidae)].

    PubMed

    Naumova, E I; Zharova, G K; Chistova, T Yu; Varshavskii, A A; Formozov, N A

    2015-01-01

    The distribution of fibers of different sizes in the gastrointestinal tract in two species of pikas--Pallas' pika Ochotonapallasi and daurian pika O. dauurica--was studied. It was established that fibers of small-sized fractions dominated in all organs of the digestive tract of both pika species, the proportion of which in the stomach proved to be even higher than in fine-grinding voles. No distinct changes in the composition of the size fractions of fibers from organ to organ were observed in the studied individuals of both species, which may be due to frequent consumption of finely dispersed cecotrophs by pikas, which enrich the primary chewed food with small fibers. PMID:26021158

  2. Digestive tract morphology of the Neotropical piscivorous fish Cichla kelberi (Perciformes: Cichlidae) introduced into an oligotrophic Brazilian reservoir.

    PubMed

    dos Santos, Alejandra Filippo Gonzalez Neves; dos Santos, Luciano Neves; Araújo, Francisco Gerson

    2011-09-01

    Despite being one of the most well-known cichlid fish of importance to artisanal and sport fishing, and among the largest fishes in the Neotropics, data on digestive tract anatomy of peacock basses (Cichla spp.) are largely lacking, especially for non-native populations. In this paper, we describe for the first time the digestive tract morphology of Cichla kelberi, a voracious piscivore that was introduced in the 1950s into an oligotrophic and physically low-complex impoundment in Brazil. Peacock basses were collected between 1994 and 2002 in Lajes Reservoir, through gillnets (25 to 55mm mesh; 20-50 x 2m), seines (10 x 2.5m; 8.0mm mesh), cast nets and angling. All the fishes were kept on ice in the field and then transferred to the laboratory, where they were identified, measured, weighed and dissected for digestive tract analyses. The Index of Relative Importance-IRI was calculated for diet characterization while linear and non-linear regressions were performed to assess growth patterns of four morphological characters related to feeding (e.g. mouth width, mouth height, stomach length and intestine length) and the number of gill rakers during the C. kelberi ontogeny. Most digestive tract structures were directly related to the piscivorous diet of C. kelberi, indicating that peacock bass is a diurnal, bathypelagic and gape-size limited predator that feeds largely on shallow-water prey species within the littoral zone. Mouth width and height grew allometrically (b > 1) with the size of peacock bass, broadening the size range in which prey can be eaten, but especially for predators smaller than -400mm of total length. Differently, stomach and intestine lengths increased isometrically (b = 1), which could constrain prey consumption for adult C. kelberi, especially those at advanced stages of gonadal maturation. The presence of longer-drawn, sharp and furcated gill rakers in C. kelberi may be related to increased prey retention in the resource-limited Lajes Reservoir

  3. Macroscopic digestive tract anatomy of two small antelopes, the blackbuck (Antilope cervicapra) and the Arabian sand gazelle (Gazella subgutturosa marica).

    PubMed

    Sauer, Cathrine; Bertelsen, Mads F; Hammer, Sven; Lund, Peter; Weisbjerg, Martin R; Clauss, Marcus

    2016-10-01

    The digestive tract anatomy of 14 blackbucks (Antilope cervicapra) and seven Arabian sand gazelles (Gazella subgutturosa marica) was quantified by dimensions, area and weight. Data from the two small-sized antilopinae were evaluated against a larger comparative data set from other ruminants classified as having either a 'cattle-type' or 'moose-type' digestive system. The digestive anatomy of the blackbuck resembled that of 'cattle-type' ruminants, which corresponds to their feeding ecology and previous studies of solute and particle retention time; however, a surprising exception was the remarkably small omasum in this species, which makes the blackbuck stand out from the general rule of a relatively large omasum in grazing ruminants. Sand gazelles had morphological features that corresponded more to the 'moose type' or an intermediate position, although previous studies of solute and particle retention time had led to the expectation of a more 'cattle-type' anatomy. The results show that outliers to general morphological trends exist, that findings on physiology and anatomy do not always match completely and that differences in the digestive morphology among ruminant species are more difficult to demonstrate at the lower end of the body mass range. PMID:26514913

  4. Macroscopic digestive tract anatomy of two small antelopes, the blackbuck (Antilope cervicapra) and the Arabian sand gazelle (Gazella subgutturosa marica).

    PubMed

    Sauer, Cathrine; Bertelsen, Mads F; Hammer, Sven; Lund, Peter; Weisbjerg, Martin R; Clauss, Marcus

    2016-10-01

    The digestive tract anatomy of 14 blackbucks (Antilope cervicapra) and seven Arabian sand gazelles (Gazella subgutturosa marica) was quantified by dimensions, area and weight. Data from the two small-sized antilopinae were evaluated against a larger comparative data set from other ruminants classified as having either a 'cattle-type' or 'moose-type' digestive system. The digestive anatomy of the blackbuck resembled that of 'cattle-type' ruminants, which corresponds to their feeding ecology and previous studies of solute and particle retention time; however, a surprising exception was the remarkably small omasum in this species, which makes the blackbuck stand out from the general rule of a relatively large omasum in grazing ruminants. Sand gazelles had morphological features that corresponded more to the 'moose type' or an intermediate position, although previous studies of solute and particle retention time had led to the expectation of a more 'cattle-type' anatomy. The results show that outliers to general morphological trends exist, that findings on physiology and anatomy do not always match completely and that differences in the digestive morphology among ruminant species are more difficult to demonstrate at the lower end of the body mass range.

  5. Effects of cooked navy bean powder on apparent total tract nutrient digestibility and safety in healthy adult dogs.

    PubMed

    Forster, G M; Hill, D; Gregory, G; Weishaar, K M; Lana, S; Bauer, J E; Ryan, E P

    2012-08-01

    Dry beans (Phaseolus vulgaris L., Fabaceae) are a low glycemic index food containing protein, fiber, minerals, essential vitamins, and bioactive compounds and have not been evaluated for inclusion in commercial canine diets. The objective of this study was to establish the apparent total tract digestibility and safety of cooked navy bean powder when incorporated into a canine diet formulation at 25% (wt/wt) compared with a macro- and micro-nutrient matched control. Twenty-one healthy, free-living, male and female adult dogs of different breeds were used in a randomized, blinded, placebo controlled, 28-d dietary intervention study. Apparent total tract energy and nutrient digestibility of the navy bean powder diet were compared with the control diet. Digestibilities and ME content were 68.58 and 68.89% DM, 78.22 and 79.49% CP, 77.57 and 74.91% OM, 94.49 and 93.85% acid hydrolyzed fat, and 3,313 and 3,195 kcal ME/kg for the navy bean diet and control diet, respectively. No differences were observed between the groups. No increased flatulence or major change in fecal consistency was observed. Navy bean powder at 25% (wt/wt) of total diet was determined to be palatable (on the basis of intake and observation) and digestible in a variety of dog breeds. No changes were detected in clinical laboratory values, including complete blood counts, blood biochemical profiles, and urinalysis in either the bean or control diet groups. These results indicate that cooked navy bean powder can be safely included as a major food ingredient in canine diet formulations and provide a novel quality protein source, and its use warrants further investigation as a functional food for chronic disease control and prevention.

  6. Effects of cooked navy bean powder on apparent total tract nutrient digestibility and safety in healthy adult dogs.

    PubMed

    Forster, G M; Hill, D; Gregory, G; Weishaar, K M; Lana, S; Bauer, J E; Ryan, E P

    2012-08-01

    Dry beans (Phaseolus vulgaris L., Fabaceae) are a low glycemic index food containing protein, fiber, minerals, essential vitamins, and bioactive compounds and have not been evaluated for inclusion in commercial canine diets. The objective of this study was to establish the apparent total tract digestibility and safety of cooked navy bean powder when incorporated into a canine diet formulation at 25% (wt/wt) compared with a macro- and micro-nutrient matched control. Twenty-one healthy, free-living, male and female adult dogs of different breeds were used in a randomized, blinded, placebo controlled, 28-d dietary intervention study. Apparent total tract energy and nutrient digestibility of the navy bean powder diet were compared with the control diet. Digestibilities and ME content were 68.58 and 68.89% DM, 78.22 and 79.49% CP, 77.57 and 74.91% OM, 94.49 and 93.85% acid hydrolyzed fat, and 3,313 and 3,195 kcal ME/kg for the navy bean diet and control diet, respectively. No differences were observed between the groups. No increased flatulence or major change in fecal consistency was observed. Navy bean powder at 25% (wt/wt) of total diet was determined to be palatable (on the basis of intake and observation) and digestible in a variety of dog breeds. No changes were detected in clinical laboratory values, including complete blood counts, blood biochemical profiles, and urinalysis in either the bean or control diet groups. These results indicate that cooked navy bean powder can be safely included as a major food ingredient in canine diet formulations and provide a novel quality protein source, and its use warrants further investigation as a functional food for chronic disease control and prevention. PMID:22367072

  7. Neurogenic inflammation in the upper digestive tract of the mule duck: effect of a chemical algogen and force-feeding.

    PubMed

    Servière, J; Carriere, M; Duvaux-Ponter, C; Guy, G; Roussel, S

    2011-12-01

    1.The objectives were to quantify the presence of neurogenic inflammation in 4 regions of the upper digestive tract of anaesthetised ducks (post-pharynx, pseudo-crop, transition between the pseudo-crop and the proventriculus, and proventriculus) after application of HCl stimulation of up to 4 M in the pseudo-crop. 2.The second objective was to quantify the presence of neurogenic inflammation in the same digestive tract regions as mentioned above during 4 feeding periods of foie gras production (rearing, preparation to force-feeding, and second and last meals of the force-feeding period). 3. Extravasation increased above a HCl stimulation threshold of 2 M. Furthermore, more extravasation was observed in the proventriculus compared to the other regions (P < 0·001). 4.Highest extravasation responses were observed in the proventriculus and the pseudo-crop at the end of the preparation period, and in the proventriculus after the second forced meal, compared with the rearing period (P < 0·01), with a return to rearing level at the end of force-feeding. 5.Such a kinetic could be indicative of a relative mildness of the irritant components associated with this feeding practice.

  8. [Bariatric surgery, stomas and other digestive tract reductions: Insufficient data and recommendations to adapt medicines regimens in therapeutic practice].

    PubMed

    Bernard, Élodie; Charpiat, Bruno; Mabrut, Jean-Yves; Dode, Xavier; Garcia, Stephan; Le Duff, Michel; Rose, François-Xavier; Ducerf, Christian

    2015-11-01

    Surgery modifying digestive tract may alter drugs pharmacokinetics. To maintain concentrations of active substance in their therapeutic ranges, a dosage adjustment or change of drug may be necessary. This is particularly important when no pharmacological or pharmacodynamic parameter reflecting the medication effectiveness is easily measurable. Our objective was to gather the information and documentary tools that can guide prescription in these patients with rearranged digestive tract. We searched information on the documentary portals of French agencies, on gray literature, on MEDLINE and in the summaries product characteristics. No information was found on the website of French agencies, sparse data were identified in gray literature. Some document are discordant, most are imprecise. One hundred and ten studies or case reports referenced on MEDLINE describe 79 medications pharmacokinetics after gastrointestinal surgery. Four are not available in France. Six literature reviews were found. Four summaries of product characteristics provided information related to drug absorption. No documentary tool adapted to clinical routine exists. This unsatisfactory situation is a barrier to optimal patients care. Information is available. It is however necessary to gather under an ergonomic shape adapted to clinical routine, bringing the surgery type, pharmacokinetic changes induced and what to do about the dose adjustment. PMID:26358672

  9. Relative distribution of gastrin-, CCK-8-, NPY- and CGRP-immunoreactive cells in the digestive tract of dorado (Salminus brasiliensis).

    PubMed

    Pereira, R T; Costa, L S; Oliveira, I R C; Araújo, J C; Aerts, M; Vigliano, F A; Rosa, P V

    2015-04-01

    The endocrine cells (ECs) of the gastrointestinal mucosa form the largest endocrine system in the body, not only in terms of cell numbers but also in terms of the different produced substances. Data describing the association between the relative distributions of the peptide-specific ECs in relation to feeding habits can be useful tools that enable the creation of a general expected pattern of EC distribution. We aimed to investigate the distribution of ECs immunoreactive for the peptides gastrin (GAS), cholecystokinin (CCK-8), neuropeptide Y (NPY), and calcitonin gene-related peptide (CGRP) in different segments of the digestive tract of carnivorous fish dorado (Salminus brasiliensis) by using immunohistochemistry procedures. The distribution of endocrine cells immunoreactive for gastrin (GAS), cholecystokinin (CCK-8), neuropeptide Y (NPY), and calcitonin gene-related peptide (CGRP) in digestive tract of dorado S. brasiliensis was examined by immunohistochemistry. The results describe the association between the distribution of the peptide-specific endocrine cells and feeding habits in different carnivorous fish. The largest number of endocrine cells immunoreactive for GAS, CCK-8, and CGRP were found in the pyloric stomach region and the pyloric caeca. However, NPY-immunoreactive endocrine cells were markedly restricted to the midgut. The distribution pattern of endocrine cells identified in S. brasiliensis is similar to that found in other carnivorous fishes.

  10. [Bariatric surgery, stomas and other digestive tract reductions: Insufficient data and recommendations to adapt medicines regimens in therapeutic practice].

    PubMed

    Bernard, Élodie; Charpiat, Bruno; Mabrut, Jean-Yves; Dode, Xavier; Garcia, Stephan; Le Duff, Michel; Rose, François-Xavier; Ducerf, Christian

    2015-11-01

    Surgery modifying digestive tract may alter drugs pharmacokinetics. To maintain concentrations of active substance in their therapeutic ranges, a dosage adjustment or change of drug may be necessary. This is particularly important when no pharmacological or pharmacodynamic parameter reflecting the medication effectiveness is easily measurable. Our objective was to gather the information and documentary tools that can guide prescription in these patients with rearranged digestive tract. We searched information on the documentary portals of French agencies, on gray literature, on MEDLINE and in the summaries product characteristics. No information was found on the website of French agencies, sparse data were identified in gray literature. Some document are discordant, most are imprecise. One hundred and ten studies or case reports referenced on MEDLINE describe 79 medications pharmacokinetics after gastrointestinal surgery. Four are not available in France. Six literature reviews were found. Four summaries of product characteristics provided information related to drug absorption. No documentary tool adapted to clinical routine exists. This unsatisfactory situation is a barrier to optimal patients care. Information is available. It is however necessary to gather under an ergonomic shape adapted to clinical routine, bringing the surgery type, pharmacokinetic changes induced and what to do about the dose adjustment.

  11. Carbaryl-induced histopathologic alterations in the digestive tract of the Levantine frog, Pelophylax bedriagae (Anura: Ranidae).

    PubMed

    Çakici, Özlem

    2014-08-01

    In this study, histopathologic changes following carbaryl exposure for 96 hr were investigated in the digestive tract of Levantine frog, Pelophylax bedriagae. Adult frogs were exposed to carbaryl once by oral gavage in concentrations of 0.05, 0.1, and 0.2 mg/g. Histopathological changes were more prominent in medium- (0.1 mg/g) and high-dose (0.2 mg/g) groups than in the low-dose (0.05 mg/g) group. Esophageal cells showed vacuolization, cellular swelling, nuclear pyknosis, karyolysis, and necrosis. Additionally, esophageal glandular atrophy and infiltration of inflammatory cells around esophageal glands were observed at medium and high doses. In the stomach, there were prominent histopathologic defects such as cellular swelling and necrosis in gastric glands, necrotic cells within the interstitial spaces, separation of epithelial cell layer, congested vessels, and hemorrhage at medium and high doses. In the intestine, detachment of epithelial layer, epithelial cell disorganization, inflammation, and necrosis were detected at medium and high doses. The results of this study showed that carbaryl caused adverse effects on the digestive tract of the Levantine frog, P. bedriagae.

  12. Successful Experience of Laparoscopic Pancreaticoduodenectomy and Digestive Tract Reconstruction With Minimized Complications Rate by 14 Case Reports

    PubMed Central

    Fan, Yong; Zhao, Yanhui; Pang, Lan; Kang, Yingxing; Kang, Boxiong; Liu, Yongyong; Fu, Jie; Xia, Bowei; Wang, Chen; Zhang, Youcheng

    2016-01-01

    Abstract Laparoscopic pancreatic surgery is one of the most sophisticated and advanced applications of laparoscopy in the current surgical practice. The adoption of laparoscopic pancreaticoduodenectomy (LPD) has been relatively slow due to the technical challenges. The aim of this study is to review and characterize our successful LPD experiences in patients with distal bile duct carcinoma, periampullary adenocarcinoma, pancreas head cancer, and duodenal cancer and evaluate the clinical outcomes of LPD for its potential in oncologic surgery applications. We retrospectively analyzed the clinical data from 14 patients who underwent LPD from August 2013 to February 2015 in our institute. We presented our LPD experience with no cases converted to open surgery in all 14 cases, which included 10 cases of laparoscopic digestive tract reconstruction and 4 cases of open digestive tract reconstructions. There were no deaths during the perioperative period and no case of gastric emptying disorder or postoperative bleeding. The other clinical indexes were comparable to or better than open surgery. Based on our experience, LPD could be potentially safe and feasible for the treatment of early pancreas head cancer, distal bile duct carcinoma, periampullary adenocarcinoma, and duodenal cancer. The master of LPD procedure requires technical expertise but it can be accomplished with a short learning curve. PMID:27124014

  13. Endosymbiotic and Host Proteases in the Digestive Tract of the Invasive Snail Pomacea canaliculata: Diversity, Origin and Characterization

    PubMed Central

    Godoy, Martín S.; Castro-Vasquez, Alfredo; Vega, Israel A.

    2013-01-01

    Digestive proteases of the digestive tract of the apple snail Pomacea canaliculata were studied. Luminal protease activity was found in the crop, the style sac and the coiled gut and was significantly higher in the coiled gut. Several protease bands and their apparent molecular weights were identified in both tissue extracts and luminal contents by gel zymography: (1) a 125 kDa protease in salivary gland extracts and in the crop content; (2) a 30 kDa protease throughout all studied luminal contents and in extracts of the midgut gland and of the endosymbionts isolated from this gland; (3) two proteases of 145 and 198 kDa in the coiled gut content. All these proteases were inhibited by aprotinin, a serine-protease inhibitor, and showed maximum activity between 30°C and 35°C and pH between 8.5 and 9.5. Tissue L-alanine-N-aminopeptidase activity was determined in the wall of the crop, the style sac and the coiled gut and was significantly higher in the coiled gut. Our findings show that protein digestion in P. canaliculata is carried out through a battery of diverse proteases originated from the salivary glands and the endosymbionts lodged in the midgut gland and by proteases of uncertain origin that occur in the coiled gut lumen. PMID:23818959

  14. Endosymbiotic and host proteases in the digestive tract of the invasive snail Pomacea canaliculata: diversity, origin and characterization.

    PubMed

    Godoy, Martín S; Castro-Vazquez, Alfredo; Castro-Vasquez, Alfredo; Vega, Israel A

    2013-01-01

    Digestive proteases of the digestive tract of the apple snail Pomacea canaliculata were studied. Luminal protease activity was found in the crop, the style sac and the coiled gut and was significantly higher in the coiled gut. Several protease bands and their apparent molecular weights were identified in both tissue extracts and luminal contents by gel zymography: (1) a 125 kDa protease in salivary gland extracts and in the crop content; (2) a 30 kDa protease throughout all studied luminal contents and in extracts of the midgut gland and of the endosymbionts isolated from this gland; (3) two proteases of 145 and 198 kDa in the coiled gut content. All these proteases were inhibited by aprotinin, a serine-protease inhibitor, and showed maximum activity between 30°C and 35°C and pH between 8.5 and 9.5. Tissue L-alanine-N-aminopeptidase activity was determined in the wall of the crop, the style sac and the coiled gut and was significantly higher in the coiled gut. Our findings show that protein digestion in P. canaliculata is carried out through a battery of diverse proteases originated from the salivary glands and the endosymbionts lodged in the midgut gland and by proteases of uncertain origin that occur in the coiled gut lumen.

  15. Development of digestive tract and enzyme activities during the early ontogeny of the tropical gar Atractosteus tropicus.

    PubMed

    Frías-Quintana, C A; Márquez-Couturier, G; Alvarez-González, C A; Tovar-Ramírez, D; Nolasco-Soria, H; Galaviz-Espinosa, M A; Martínez-García, R; Camarillo-Coop, S; Martínez-Yañez, R; Gisbert, E

    2015-10-01

    Changes in digestive enzyme activity and histology were studied in Atractosteus tropicus embryos, larvae and juvenile periods. Alkaline protease, chymotrypsin, carboxypeptidase A, lipase and α-amylase were detected in all periods and gradually increased until reaching the maximum peak in juveniles; meanwhile, acid protease was first detected at 5 days after hatching (dah) when first feeding started and trypsin and leucine aminopeptidase activities were detected from 19 dah, their values being increased gradually until reaching a maximum value at 31 dah. Acid and alkaline phosphatase activities increased from yolk-sac absorption (3 dah) until day 31 after hatching. Zymogram for acid protease showed two bands in active forms (0.4 and 0.5 Rfs) from day 5 after hatching and a third protease form (0.3 Rf) that appears at 31 dah. Two active forms (26.3 and 24.9 kDa) were detected using SDS-PAGE alkaline proteases zymogram at 5 dah, and an additional active form (44.1 kDa) was detected at 7 dah. Regarding the histological development of the digestive system, the exocrine pancreas containing zymogen granules was already visible at 3 dah, whereas at 5 dah first gastric glands were already detected in the stomach. Between 7 and 9 dah, the digestive tract of A. tropicus resembled that of a juvenile specimen with a well-developed and short oesophagus, stomach divided into a glandular and non-glandular (pyloric) stomach, folded intestine with pyloric caeca and a well-developed spiral valve (posterior intestine). Considering this, larvae of A. tropicus are capable of digesting several foods from yolk absorption (3 dah), maximizing its activities at 15 dah, age at which the organisms maximize its capability to absorb nutrients from diets provided.

  16. Digestive Organ in the Female Reproductive Tract Borrows Genes from Multiple Organ Systems to Adopt Critical Functions

    PubMed Central

    Meslin, Camille; Plakke, Melissa S.; Deutsch, Aaron B.; Small, Brandon S.; Morehouse, Nathan I.; Clark, Nathan L.

    2015-01-01

    Persistent adaptive challenges are often met with the evolution of novel physiological traits. Although there are specific examples of single genes providing new physiological functions, studies on the origin of complex organ functions are lacking. One such derived set of complex functions is found in the Lepidopteran bursa copulatrix, an organ within the female reproductive tract that digests nutrients from the male ejaculate or spermatophore. Here, we characterized bursa physiology and the evolutionary mechanisms by which it was equipped with digestive and absorptive functionality. By studying the transcriptome of the bursa and eight other tissues, we revealed a suite of highly expressed and secreted gene products providing the bursa with a combination of stomach-like traits for mechanical and enzymatic digestion of the male spermatophore. By subsequently placing these bursa genes in an evolutionary framework, we found that the vast majority of their novel digestive functions were co-opted by borrowing genes that continue to be expressed in nonreproductive tissues. However, a number of bursa-specific genes have also arisen, some of which represent unique gene families restricted to Lepidoptera and may provide novel bursa-specific functions. This pattern of promiscuous gene borrowing and relatively infrequent evolution of tissue-specific duplicates stands in contrast to studies of the evolution of novelty via single gene co-option. Our results suggest that the evolution of complex organ-level phenotypes may often be enabled (and subsequently constrained) by changes in tissue specificity that allow expression of existing genes in novel contexts, such as reproduction. The extent to which the selective pressures encountered in these novel roles require resolution via duplication and sub/neofunctionalization is likely to be determined by the need for specialized reproductive functionality. Thus, complex physiological phenotypes such as that found in the bursa offer

  17. Endogenous intestinal losses of calcium and true total tract digestibility of calcium in canola meal fed to growing pigs.

    PubMed

    González-Vega, J C; Walk, C L; Liu, Y; Stein, H H

    2013-10-01

    An experiment was conducted to test the hypothesis that values for apparent total tract digestibility (ATTD) of Ca in pigs are influenced by endogenous Ca lost from the gastrointestinal tract. The objective was to determine the endogenous loss of Ca, the ATTD of Ca, and the true total tract digestibility (TTTD) of Ca in canola meal without and with microbial phytase. The second objective was to determine the balance of Ca in pigs fed diets based on canola meal without or with microbial phytase. Forty-eight growing barrows (initial BW: 16.72 ± 2.52 kg) were allotted to 8 dietary treatments in a randomized complete block design with 6 pigs per treatment. Diets were based on sucrose, cornstarch, potato protein isolate, corn gluten meal, and canola meal. Diets were formulated to contain 0.08, 0.16, 0.24, or 0.32% Ca from canola meal. All diets were formulated with 0 or 1,500 units/kg of microbial phytase and contained 0.32% digestible P. Feces and urine samples were collected from d 6 to 11. Total endogenous losses of Ca were determined using the regression procedure. Results indicated that ATTD of Ca and Ca retention increased (P < 0.05) if dietary Ca increased and also increased (P < 0.01) when phytase was added to the diets. The estimated total endogenous loss of Ca was 0.160 and 0.189 g/kg DMI for canola meal without and with microbial phytase, respectively, and these values were not different. The TTTD of Ca increased (P < 0.01) if phytase was used but was not affected by the level of dietary Ca. As dietary Ca increased, the amount of Ca absorbed and retained increased (P < 0.01) to a greater extent if phytase was used than when no phytase was included in the diet (interaction, P < 0.05). Fecal P excretion increased (P < 0.01) as dietary Ca increased but was reduced (P < 0.01) by the use of phytase. The ATTD of P decreased (P < 0.01) with increasing dietary Ca to a lesser extent if phytase was used than when no phytase was used (interaction, P < 0.01). In

  18. Helminth parasites of the digestive tract of the oystercatcher, Haematopus ostralegus, in the Wadden Sea, The Netherlands

    NASA Astrophysics Data System (ADS)

    Borgsteede, F. H. M.; Van den Broek, E.; Swennen, C.

    The digestive tracts of 90 oystercatchers (equal numbers of males and females and of juveniles, subadults and adults) wintering in the Dutch Wadden Sea were examined for helminth parasites. The nematodes Capillaria sp. (36.7%) and Streptocara crassicauda (7.8%) were found in the stomach. Unidentified cestodes (76.7%) and the trematodes Psilostomum brevicolle (42.2%), Notocotylus sp. (81.1%), and unidentified gymnophallids (100%) were found in the intestine and caeca. Two birds were infected with Gymnophallidae only, while all other birds contained additional helminth species. Compared with subadult and adult birds, the juveniles had significantly more infections with Capillaria sp. and cestodes. Moreover, the juveniles were infected with a greater variety of species. No further relation was found between the presence of helminths or worm numbers and age groups or sexes of birds.

  19. [Tumor regression following local chemotherapy in carcinomas of the upper respiratory and digestive tracts. The viewpoint of the pathologist].

    PubMed

    Micheau, C; Richard, J M; Marandas, P; Bosq, J; Caillaud, J M

    1983-01-01

    Few pathologists have given much thought to the problem of post-chemotherapeutic tumoral regression of upper respiratory and digestive tract carcinoma. In other oncological fields (pediatry: nephroblastoma, embryonic sarcoma, osteosarcoma; gynecology: mammary tumors...) pre- and post-chemotherapy tissue studies have led to histological grading of prognostic value (particularly well known is that of Rosen et al). Numerous specimens were examined following operations for cancer, including pelvimandibulectomy, buccopharyngectomy, facial resection... Possible tumoral changes were evaluated using a conventional scale of regression based on 6 histologic degrees, and findings were of prognostic significance when compared with the initial biopsy results. This evaluation scale may require modification in the near future since recently introduced chemotherapy, particularly cisplatinum, appears to have a more potent and more specific effect on histologie features.

  20. Morphallactic regeneration as revealed by region-specific gene expression in the digestive tract of Enchytraeus japonensis (Oligochaeta, Annelida).

    PubMed

    Takeo, Makoto; Yoshida-Noro, Chikako; Tochinai, Shin

    2008-05-01

    Enchytraeus japonensis is a small oligochaete, which primarily reproduces asexually by fragmentation and regeneration. For precise analysis of the pattern formation during regeneration, we isolated three region-specific genes (EjTuba, mino, and horu) expressed in the digestive tract. In growing worms, the expression of EjTuba in the head and mino in the trunk region just posterior to the head were observed in defined body segments, while the expression areas of EjTuba in the trunk and horu were proportional to the total number of body segments. In the regeneration process, expression of these genes disappeared once and recovered to their original pattern by day 7. In abnormal regeneration such as a bipolar head, mino was still expressed in the region next to both the normal and the ectopic heads. These results suggest that there is morphallactic as well as epimorphic or inductive regulation of the body patterning during regeneration of E. japonensis. PMID:18393309

  1. Ultrastructure and histochemistry of the digestive tract of juvenile Paramphistomum epiclitum (Paramphistomidae: Digenea) during migration in Indian ruminants.

    PubMed

    Mattison, R G; Hanna, R E; Nizami, W A

    1992-12-01

    The digestive tract of juvenile Paramphistomum epiclitum consists of a foregut with a highly muscular terminal pharynx and an oesophagus, which leads to a pair of unbranched and blind-ending intestinal caeca. A syncytium lining the foregut is continuous with the external tegument and displays similar sensory papillae and secretory bodies (T1 and T2). A third type of secretory body (T3) is confined to the oesophageal cytons of newly excysted juveniles and is first evident in the syncytium by day 14 of migration. An epithelium lining the caeca is composed of a single layer of morphologically uniform cells whose apical surface is amplified by microvilli. Dense secretions synthesized in the caecal epithelium of mature cercariae are released during migration by a mechanism resembling modified apocrine discharge. The caecal epithelium of migrating juveniles undergoes a 10-fold increase in surface amplification (irrespective of growth) during its transition from a primarily secretory tissue to one apparently specialized for absorption. PMID:1487369

  2. Expression pattern of peptide and amino acid genes in digestive tract of transporter juvenile turbot ( Scophthalmus maximus L.)

    NASA Astrophysics Data System (ADS)

    Xu, Dandan; He, Gen; Mai, Kangsen; Zhou, Huihui; Xu, Wei; Song, Fei

    2016-04-01

    Turbot ( Scophthalmus maximus L.), a carnivorous fish species with high dietary protein requirement, was chosen to examine the expression pattern of peptide and amino acid transporter genes along its digestive tract which was divided into six segments including stomach, pyloric caeca, rectum, and three equal parts of the remainder of the intestine. The results showed that the expression of two peptide and eleven amino acid transporters genes exhibited distinct patterns. Peptide transporter 1 (PepT1) was rich in proximal intestine while peptide transporter 2 (PepT2) was abundant in distal intestine. A number of neutral and cationic amino acid transporters expressed richly in whole intestine including B0-type amino acid transporter 1 (B0AT1), L-type amino acid transporter 2 (LAT2), T-type amino acid transporter 1 (TAT1), proton-coupled amino acid transporter 1 (PAT1), y+L-type amino acid transporter 1 (y+LAT1), and cationic amino acid transporter 2 (CAT2) while ASC amino acid transporter 2 (ASCT2), sodium-coupled neutral amino acid transporter 2 (SNAT2), and y+L-type amino acid transporter 2 (y+LAT2) abundantly expressed in stomach. In addition, system b0,+ transporters (rBAT and b0,+AT) existed richly in distal intestine. These findings comprehensively characterized the distribution of solute carrier family proteins, which revealed the relative importance of peptide and amino acid absorption through luminal membrane. Our findings are helpful to understand the mechanism of the utilization of dietary protein in fish with a short digestive tract.

  3. Identification of iron and heme utilization genes in Aeromonas and their role in the colonization of the leech digestive tract

    PubMed Central

    Maltz, Michele; LeVarge, Barbara L.; Graf, Joerg

    2015-01-01

    It is known that many pathogens produce high-affinity iron uptake systems like siderophores and/or proteins for utilizing iron bound to heme-containing molecules, which facilitate iron-acquisition inside a host. In mutualistic digestive-tract associations, iron uptake systems have not been as well studied. We investigated the importance of two iron utilization systems within the beneficial digestive-tract association Aeromonas veronii and the medicinal leech, Hirudo verbana. Siderophores were detected in A. veronii using chrome azurol S. Using a mini Tn5, a transposon insertion in viuB generated a mutant unable to utilize iron using siderophores. The A. veronii genome was then searched for genes potentially involved in iron utilization bound to heme-containing molecules. A putative outer membrane heme receptor (hgpB) was identified with a transcriptional activator, termed hgpR, downstream. The hgpB gene was interrupted with an antibiotic resistance cassette in both the parent strain and the viuB mutant, yielding an hgpB mutant and a mutant with both iron uptake systems inactivated. In vitro assays indicated that hgpB is involved in utilizing iron bound to heme and that both iron utilization systems are important for A. veronii to grow in blood. In vivo colonization assays revealed that the ability to acquire iron from heme-containing molecules is critical for A. veronii to colonize the leech gut. Since iron and specifically heme utilization is important in this mutualistic relationship and has a potential role in virulence factor of other organisms, genomes from different Aeromonas strains (both clinical and environmental) were queried with iron utilization genes of A. veronii. This analysis revealed that in contrast to the siderophore utilization genes heme utilization genes are widely distributed among aeromonads. The importance of heme utilization in the colonization of the leech further confirms that symbiotic and pathogenic relationships possess similar

  4. Identification of iron and heme utilization genes in Aeromonas and their role in the colonization of the leech digestive tract.

    PubMed

    Maltz, Michele; LeVarge, Barbara L; Graf, Joerg

    2015-01-01

    It is known that many pathogens produce high-affinity iron uptake systems like siderophores and/or proteins for utilizing iron bound to heme-containing molecules, which facilitate iron-acquisition inside a host. In mutualistic digestive-tract associations, iron uptake systems have not been as well studied. We investigated the importance of two iron utilization systems within the beneficial digestive-tract association Aeromonas veronii and the medicinal leech, Hirudo verbana. Siderophores were detected in A. veronii using chrome azurol S. Using a mini Tn5, a transposon insertion in viuB generated a mutant unable to utilize iron using siderophores. The A. veronii genome was then searched for genes potentially involved in iron utilization bound to heme-containing molecules. A putative outer membrane heme receptor (hgpB) was identified with a transcriptional activator, termed hgpR, downstream. The hgpB gene was interrupted with an antibiotic resistance cassette in both the parent strain and the viuB mutant, yielding an hgpB mutant and a mutant with both iron uptake systems inactivated. In vitro assays indicated that hgpB is involved in utilizing iron bound to heme and that both iron utilization systems are important for A. veronii to grow in blood. In vivo colonization assays revealed that the ability to acquire iron from heme-containing molecules is critical for A. veronii to colonize the leech gut. Since iron and specifically heme utilization is important in this mutualistic relationship and has a potential role in virulence factor of other organisms, genomes from different Aeromonas strains (both clinical and environmental) were queried with iron utilization genes of A. veronii. This analysis revealed that in contrast to the siderophore utilization genes heme utilization genes are widely distributed among aeromonads. The importance of heme utilization in the colonization of the leech further confirms that symbiotic and pathogenic relationships possess similar

  5. Corn or sorghum wet distiller's grains with solubles in combination with steam-flaked corn: Feedlot cattle performance, carcass characteristics, and apparent total tract digestibility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two studies were conducted to evaluate corn (CDG) and sorghum (SDG) wet distiller's grains with solubles on feedlot cattle performance, carcass characteristics, apparent total tract digestion of nutrients, and marker retention time. In Experiment 1, 224 steers were used in a randomized complete bloc...

  6. Expression patterns suggest that despite considerable functional redundancy, galectin-4 and -6 play distinct roles in normal and damaged mouse digestive tract.

    PubMed

    Houzelstein, Denis; Reyes-Gomez, Edouard; Maurer, Marie; Netter, Pierre; Higuet, Dominique

    2013-05-01

    The galectin-4 protein is mostly expressed in the digestive tract and is associated with lipid raft stabilization, protein apical trafficking, wound healing, and inflammation. While most mammalian species, including humans, have a single Lgals4 gene, some mice have two paralogues: Lgals4 and Lgals6. So far, their significant similarities have hindered the analysis of their respective expression and function. We took advantage of two antibodies that discriminate between the galectin-4 and galectin-6 proteins to document their patterns of expression in the normal and the dextran sodium sulfate (DSS)-damaged digestive tract in the mouse. In the normal digestive tract, their pattern of expression from tongue to colon is quite similar, which suggests functional redundancy. However, the presence of galectin-4, but not galectin-6, in the lamina propria of the DSS-damaged colon, its association with luminal colonic bacteria, and differences in subcellular localization of these proteins suggest that they also have distinct roles in the normal and the damaged mouse digestive tract. Our results provide a rare example of ancestral and derived functions evolving after tandem gene duplication.

  7. Influence of the Biliary System on Biliary Bacteria Revealed by Bacterial Communities of the Human Biliary and Upper Digestive Tracts.

    PubMed

    Ye, Fuqiang; Shen, Hongzhang; Li, Zhen; Meng, Fei; Li, Lei; Yang, Jianfeng; Chen, Ying; Bo, Xiaochen; Zhang, Xiaofeng; Ni, Ming

    2016-01-01

    Biliary bacteria have been implicated in gallstone pathogenesis, though a clear understanding of their composition and source is lacking. Moreover, the effects of the biliary environment, which is known to be generally hostile to most bacteria, on biliary bacteria are unclear. Here, we investigated the bacterial communities of the biliary tract, duodenum, stomach, and oral cavity from six gallstone patients by using 16S rRNA amplicon sequencing. We found that all observed biliary bacteria were detectable in the upper digestive tract. The biliary microbiota had a comparatively higher similarity with the duodenal microbiota, versus those of the other regions, but with a reduced diversity. Although the majority of identified bacteria were greatly diminished in bile samples, three Enterobacteriaceae genera (Escherichia, Klebsiella, and an unclassified genus) and Pyramidobacter were abundant in bile. Predictive functional analysis indicated enhanced abilities of environmental information processing and cell motility of biliary bacteria. Our study provides evidence for the potential source of biliary bacteria, and illustrates the influence of the biliary system on biliary bacterial communities.

  8. Influence of the Biliary System on Biliary Bacteria Revealed by Bacterial Communities of the Human Biliary and Upper Digestive Tracts

    PubMed Central

    Ye, Fuqiang; Shen, Hongzhang; Li, Zhen; Meng, Fei; Li, Lei; Yang, Jianfeng; Chen, Ying; Bo, Xiaochen; Zhang, Xiaofeng; Ni, Ming

    2016-01-01

    Biliary bacteria have been implicated in gallstone pathogenesis, though a clear understanding of their composition and source is lacking. Moreover, the effects of the biliary environment, which is known to be generally hostile to most bacteria, on biliary bacteria are unclear. Here, we investigated the bacterial communities of the biliary tract, duodenum, stomach, and oral cavity from six gallstone patients by using 16S rRNA amplicon sequencing. We found that all observed biliary bacteria were detectable in the upper digestive tract. The biliary microbiota had a comparatively higher similarity with the duodenal microbiota, versus those of the other regions, but with a reduced diversity. Although the majority of identified bacteria were greatly diminished in bile samples, three Enterobacteriaceae genera (Escherichia, Klebsiella, and an unclassified genus) and Pyramidobacter were abundant in bile. Predictive functional analysis indicated enhanced abilities of environmental information processing and cell motility of biliary bacteria. Our study provides evidence for the potential source of biliary bacteria, and illustrates the influence of the biliary system on biliary bacterial communities. PMID:26930491

  9. Comparison of five in vitro digestion models to in vivo experimental results: lead bioaccessibility in the human gastrointestinal tract.

    PubMed

    Van de Wiele, Tom R; Oomen, Agnes G; Wragg, Joanna; Cave, Mark; Minekus, Mans; Hack, Alfons; Cornelis, Christa; Rompelberg, Cathy J M; De Zwart, Loeckie L; Klinck, Ben; Van Wijnen, Joop; Verstraete, Willy; Sips, Adriënne J A M

    2007-07-15

    This paper presents a multi-laboratory comparison study of in vitro models assessing bioaccessibility of soil-bound lead in the human gastrointestinal tract under simulated fasted and fed conditions. Oral bioavailability data from a previous human in vivo study on the same soil served as a reference point. In general, the bioaccessible lead fraction was significantly (P<0.05) different between the in vitro methods and ranged for the fasted models from 2% to 33% and for the fed models from 7% to 29%. The in vivo bioavailability data from literature were 26.2+/-8.1% for fasted conditions, compared to 2.5+/-1.7% for fed conditions. Under fed conditions, all models returned higher bioaccessibility values than the in vivo bioavailability; whereas three models returned a lower bioaccessibility than bioavailability under fasted conditions. These differences are often due to the method's digestion parameters that need further optimization. An important outcome of this study was the determination that the method for separating the bioaccessible lead from the non-bioaccessible fraction (centrifugation, filtration, ultrafiltration) is crucial for the interpretation of the results. Bioaccessibility values from models that use more stringent separation methods better approximate in vivo bioavailability results, yet at the expense of the level of conservancy. We conclude from this study that more optimization of in vitro digestion models is needed for use in risk assessment. Moreover, attention should be paid to the laboratory separation method since it largely influences what fraction of the contaminant is considered bioaccessible.

  10. Lipid Encapsulation Provides Insufficient Total-Tract Digestibility to Achieve an Optimal Transfer Efficiency of Fatty Acids to Milk Fat

    PubMed Central

    Bainbridge, Melissa; Kraft, Jana

    2016-01-01

    Transfer efficiencies of rumen-protected n-3 fatty acids (FA) to milk are low, thus we hypothesized that rumen-protection technologies allow for biohydrogenation and excretion of n-3 FA. The objectives of this study were to i) investigate the ruminal protection and post-ruminal release of the FA derived from the lipid-encapsulated echium oil (EEO), and ii) assess the bioavailability and metabolism of the EEO-derived FA through measuring the FA content in plasma lipid fractions, feces, and milk. The EEO was tested for rumen stability using the in situ nylon bag technique, then the apparent total-tract digestibility was assessed in vivo using six Holstein dairy cattle. Diets consisted of a control (no EEO); 1.5% of dry matter (DM) as EEO and 1.5% DM as encapsulation matrix; and 3% DM as EEO. The EEO was rumen-stable and had no effect on animal production. EEO-derived FA were incorporated into all plasma lipid fractions, with the highest proportion of n-3 FA observed in cholesterol esters. Fecal excretion of EEO-derived FA ranged from 7–14%. Biohydrogenation products increased in milk, plasma, and feces with EEO supplementation. In conclusion, lipid-encapsulation provides inadequate digestibility to achieve an optimal transfer efficiency of n-3 FA to milk. PMID:27741299

  11. Changes in apparent metabolizable energy and digestive tract of broiler chickens fed diets containing irradiated meat-bone meal

    NASA Astrophysics Data System (ADS)

    Al-Masri, M. R.

    2003-05-01

    Experiments have been carried out to study the effect of feeding broiler chickens with irradiated meat-bone meal (0, 5, 10, 25, 50 kGy), at a rate of 100 g/kg diet, on the apparent metabolizable energy (AME) values, using total collection of feed and excreta, during different age periods (14-21, 21-28, 28-35 and 35-42 days) and on the biological aspects of the digestive organs during the last 4 weeks of chickens'age (14-42 days). Results indicated that feeding of broiler chickens with diets containing irradiated meat-bone meal had insignificant effects on the AME values which amounted to an average of 18.6 MJ/kg diet during the four weeks of experimental periods. The AME values increased significantly by 0.36-0.99 MJ/kg diet during the late fourth age period compared with the other earlier three age periods. No significant difference was noticed in the AME values between the second and third experimental age periods. Feeding chickens with irradiated meat-bone meal for 4 weeks (14-42 day of age) had no significant effects on the relative weights of crop, proventriculus, gizzard, duodenum, jejunum, ileum, caeca, colon, pancreas and liver. Therefore, radiation sterilized meat-bone meal could be used as feedstuff in poultry diets without any deleterious effect on the diet energy utilization and biological aspects of chickens'digestive tract.

  12. Effect of phytate, microbial phytase, fiber, and soybean oil on calculated values for apparent and standardized total tract digestibility of calcium and apparent total tract digestibility of phosphorus in fish meal fed to growing pigs.

    PubMed

    González-Vega, J C; Walk, C L; Stein, H H

    2015-10-01

    Two experiments were conducted to determine the effects of phytate, phytase, fiber, and soybean oil on apparent total tract digestibility (ATTD) and standardized total tract digestibility (STTD) of Ca and on ATTD of P in fish meal fed to growing pigs. In Exp. 1, 40 growing pigs (initial average BW: 19.16 ± 2.04 kg) were randomly allotted to 1 of 5 diets with 8 pigs per treatment and placed in metabolism crates. Four diets were used in a 2 ´ 2 factorial design with 2 levels of phytate (0 or 0.7%) and 2 levels of microbial phytase (0 or 500 phytase units/kg). The diet containing no phytate was based on sucrose, cornstarch, fish meal, casein, and soybean oil, and the diet containing 0.7% phytate was based on corn, corn germ, fish meal, casein, and soybean oil. A Ca-free diet was used to determine basal endogenous losses of Ca. Feces were collected from d 6 to 13 after a 5-d adaptation period. Results indicated that the ATTD and STTD of Ca in fish meal and the ATTD of P increased ( < 0.001) if phytase was used and were greater ( < 0.05) in the diets based on corn and corn germ. Experiment 2 was conducted to determine the effects of fiber and soybean oil on the ATTD and STTD of Ca and the ATTD of P in fish meal. Fifty growing pigs (initial average BW: 19.36 ± 0.99 kg) were randomly allotted to 1 of 5 diets with 10 pigs per treatment. Two diets contained sucrose, cornstarch, fish meal, casein, and either 0 or 8% of a synthetic source of fiber. Two additional diets contained fish meal, casein, corn, and either 1 or 7% soybean oil. A Ca-free diet was also used. Pigs were housed individually in metabolism crates and fecal samples were collected. Results indicated that fiber increased ( < 0.001) the ATTD and STTD of Ca and the ATTD of P, but the ATTD and STTD of Ca or the ATTD of P were not affected by soybean oil. In agreement with the results of Exp. 1, the ATTD and STTD of Ca and the ATTD of P in the corn-based diet were greater ( < 0.05) than those in the cornstarch

  13. An insight into the transcriptome of the digestive tract of the bloodsucking bug, Rhodnius prolixus.

    PubMed

    Ribeiro, José M C; Genta, Fernando A; Sorgine, Marcos H F; Logullo, Raquel; Mesquita, Rafael D; Paiva-Silva, Gabriela O; Majerowicz, David; Medeiros, Marcelo; Koerich, Leonardo; Terra, Walter R; Ferreira, Clélia; Pimentel, André C; Bisch, Paulo M; Leite, Daniel C; Diniz, Michelle M P; da S G V Junior, João Lídio; Da Silva, Manuela L; Araujo, Ricardo N; Gandara, Ana Caroline P; Brosson, Sébastien; Salmon, Didier; Bousbata, Sabrina; González-Caballero, Natalia; Silber, Ariel Mariano; Alves-Bezerra, Michele; Gondim, Katia C; Silva-Neto, Mário Alberto C; Atella, Georgia C; Araujo, Helena; Dias, Felipe A; Polycarpo, Carla; Vionette-Amaral, Raquel J; Fampa, Patrícia; Melo, Ana Claudia A; Tanaka, Aparecida S; Balczun, Carsten; Oliveira, José Henrique M; Gonçalves, Renata L S; Lazoski, Cristiano; Rivera-Pomar, Rolando; Diambra, Luis; Schaub, Günter A; Garcia, Elói S; Azambuja, Patrícia; Braz, Glória R C; Oliveira, Pedro L

    2014-01-01

    The bloodsucking hemipteran Rhodnius prolixus is a vector of Chagas' disease, which affects 7-8 million people today in Latin America. In contrast to other hematophagous insects, the triatomine gut is compartmentalized into three segments that perform different functions during blood digestion. Here we report analysis of transcriptomes for each of the segments using pyrosequencing technology. Comparison of transcript frequency in digestive libraries with a whole-body library was used to evaluate expression levels. All classes of digestive enzymes were highly expressed, with a predominance of cysteine and aspartic proteinases, the latter showing a significant expansion through gene duplication. Although no protein digestion is known to occur in the anterior midgut (AM), protease transcripts were found, suggesting secretion as pro-enzymes, being possibly activated in the posterior midgut (PM). As expected, genes related to cytoskeleton, protein synthesis apparatus, protein traffic, and secretion were abundantly transcribed. Despite the absence of a chitinous peritrophic membrane in hemipterans - which have instead a lipidic perimicrovillar membrane lining over midgut epithelia - several gut-specific peritrophin transcripts were found, suggesting that these proteins perform functions other than being a structural component of the peritrophic membrane. Among immunity-related transcripts, while lysozymes and lectins were the most highly expressed, several genes belonging to the Toll pathway - found at low levels in the gut of most insects - were identified, contrasting with a low abundance of transcripts from IMD and STAT pathways. Analysis of transcripts related to lipid metabolism indicates that lipids play multiple roles, being a major energy source, a substrate for perimicrovillar membrane formation, and a source for hydrocarbons possibly to produce the wax layer of the hindgut. Transcripts related to amino acid metabolism showed an unanticipated priority for

  14. An Insight into the Transcriptome of the Digestive Tract of the Bloodsucking Bug, Rhodnius prolixus

    PubMed Central

    Ribeiro, José M. C.; Genta, Fernando A.; Sorgine, Marcos H. F.; Logullo, Raquel; Mesquita, Rafael D.; Paiva-Silva, Gabriela O.; Majerowicz, David; Medeiros, Marcelo; Koerich, Leonardo; Terra, Walter R.; Ferreira, Clélia; Pimentel, André C.; Bisch, Paulo M.; Leite, Daniel C.; Diniz, Michelle M. P.; Junior, João Lídio da S. G. V.; Da Silva, Manuela L.; Araujo, Ricardo N.; Gandara, Ana Caroline P.; Brosson, Sébastien; Salmon, Didier; Bousbata, Sabrina; González-Caballero, Natalia; Silber, Ariel Mariano; Alves-Bezerra, Michele; Gondim, Katia C.; Silva-Neto, Mário Alberto C.; Atella, Georgia C.; Araujo, Helena; Dias, Felipe A.; Polycarpo, Carla; Vionette-Amaral, Raquel J.; Fampa, Patrícia; Melo, Ana Claudia A.; Tanaka, Aparecida S.; Balczun, Carsten; Oliveira, José Henrique M.; Gonçalves, Renata L. S.; Lazoski, Cristiano; Rivera-Pomar, Rolando; Diambra, Luis; Schaub, Günter A.; Garcia, Elói S.; Azambuja, Patrícia; Braz, Glória R. C.; Oliveira, Pedro L.

    2014-01-01

    The bloodsucking hemipteran Rhodnius prolixus is a vector of Chagas' disease, which affects 7–8 million people today in Latin America. In contrast to other hematophagous insects, the triatomine gut is compartmentalized into three segments that perform different functions during blood digestion. Here we report analysis of transcriptomes for each of the segments using pyrosequencing technology. Comparison of transcript frequency in digestive libraries with a whole-body library was used to evaluate expression levels. All classes of digestive enzymes were highly expressed, with a predominance of cysteine and aspartic proteinases, the latter showing a significant expansion through gene duplication. Although no protein digestion is known to occur in the anterior midgut (AM), protease transcripts were found, suggesting secretion as pro-enzymes, being possibly activated in the posterior midgut (PM). As expected, genes related to cytoskeleton, protein synthesis apparatus, protein traffic, and secretion were abundantly transcribed. Despite the absence of a chitinous peritrophic membrane in hemipterans - which have instead a lipidic perimicrovillar membrane lining over midgut epithelia - several gut-specific peritrophin transcripts were found, suggesting that these proteins perform functions other than being a structural component of the peritrophic membrane. Among immunity-related transcripts, while lysozymes and lectins were the most highly expressed, several genes belonging to the Toll pathway - found at low levels in the gut of most insects - were identified, contrasting with a low abundance of transcripts from IMD and STAT pathways. Analysis of transcripts related to lipid metabolism indicates that lipids play multiple roles, being a major energy source, a substrate for perimicrovillar membrane formation, and a source for hydrocarbons possibly to produce the wax layer of the hindgut. Transcripts related to amino acid metabolism showed an unanticipated priority for

  15. An insight into the transcriptome of the digestive tract of the bloodsucking bug, Rhodnius prolixus.

    PubMed

    Ribeiro, José M C; Genta, Fernando A; Sorgine, Marcos H F; Logullo, Raquel; Mesquita, Rafael D; Paiva-Silva, Gabriela O; Majerowicz, David; Medeiros, Marcelo; Koerich, Leonardo; Terra, Walter R; Ferreira, Clélia; Pimentel, André C; Bisch, Paulo M; Leite, Daniel C; Diniz, Michelle M P; da S G V Junior, João Lídio; Da Silva, Manuela L; Araujo, Ricardo N; Gandara, Ana Caroline P; Brosson, Sébastien; Salmon, Didier; Bousbata, Sabrina; González-Caballero, Natalia; Silber, Ariel Mariano; Alves-Bezerra, Michele; Gondim, Katia C; Silva-Neto, Mário Alberto C; Atella, Georgia C; Araujo, Helena; Dias, Felipe A; Polycarpo, Carla; Vionette-Amaral, Raquel J; Fampa, Patrícia; Melo, Ana Claudia A; Tanaka, Aparecida S; Balczun, Carsten; Oliveira, José Henrique M; Gonçalves, Renata L S; Lazoski, Cristiano; Rivera-Pomar, Rolando; Diambra, Luis; Schaub, Günter A; Garcia, Elói S; Azambuja, Patrícia; Braz, Glória R C; Oliveira, Pedro L

    2014-01-01

    The bloodsucking hemipteran Rhodnius prolixus is a vector of Chagas' disease, which affects 7-8 million people today in Latin America. In contrast to other hematophagous insects, the triatomine gut is compartmentalized into three segments that perform different functions during blood digestion. Here we report analysis of transcriptomes for each of the segments using pyrosequencing technology. Comparison of transcript frequency in digestive libraries with a whole-body library was used to evaluate expression levels. All classes of digestive enzymes were highly expressed, with a predominance of cysteine and aspartic proteinases, the latter showing a significant expansion through gene duplication. Although no protein digestion is known to occur in the anterior midgut (AM), protease transcripts were found, suggesting secretion as pro-enzymes, being possibly activated in the posterior midgut (PM). As expected, genes related to cytoskeleton, protein synthesis apparatus, protein traffic, and secretion were abundantly transcribed. Despite the absence of a chitinous peritrophic membrane in hemipterans - which have instead a lipidic perimicrovillar membrane lining over midgut epithelia - several gut-specific peritrophin transcripts were found, suggesting that these proteins perform functions other than being a structural component of the peritrophic membrane. Among immunity-related transcripts, while lysozymes and lectins were the most highly expressed, several genes belonging to the Toll pathway - found at low levels in the gut of most insects - were identified, contrasting with a low abundance of transcripts from IMD and STAT pathways. Analysis of transcripts related to lipid metabolism indicates that lipids play multiple roles, being a major energy source, a substrate for perimicrovillar membrane formation, and a source for hydrocarbons possibly to produce the wax layer of the hindgut. Transcripts related to amino acid metabolism showed an unanticipated priority for

  16. Validation of an in vitro model for predicting rumen and total-tract fiber digestibility in dairy cows fed corn silages with different in vitro neutral detergent fiber digestibilities at 2 levels of dry matter intake.

    PubMed

    Lopes, F; Cook, D E; Combs, D K

    2015-01-01

    An in vivo study was performed to validate an in vitro procedure that predicts rate of fiber digestion and total-tract neutral detergent fiber digestibility (TTNDFD). Two corn silages that differed in fiber digestibility were used in this trial. The corn silage with lower fiber digestibility (LFDCS) had the TTNDFD prediction of 36.0% of total NDF, whereas TTNDFD for the corn silage with higher fiber digestibility (HFDCS) was 44.9% of total neutral detergent fiber (NDF). Two diets (1 with LFDCS and 1 with HFDCS) were formulated and analyzed using the in vitro assay to predict the TTNDFD and rumen potentially digestible NDF (pdNDF) digestion rate. Similar diets were fed to 8 ruminally cannulated, multiparous, high-producing dairy cows in 2 replicated 4×4 Latin squares with 21-d periods. A 2×2 factorial arrangement of treatments was used with main effects of intake (restricted to approximately 90% of ad libitum intake vs. ad libitum) and corn silage of different fiber digestibility. Treatments were restricted and ad libitum LFDCS as well as restricted and ad libitum HFDCS. The input and output values predicted from the in vitro model were compared with in vivo measurements. The pdNDF intake predicted by the in vitro model was similar to pdNDF intake observed in vivo. Also, the pdNDF digestion rate predicted in vitro was similar to what was observed in vivo. The in vitro method predicted TTNDFD of 50.2% for HFDCS and 42.9% for LFDCS as a percentage of total NDF in the diets, whereas the in vivo measurements of TTNDFD averaged 50.3 and 48.6% of total NDF for the HFDCS and LFDCS diets, respectively. The in vitro TTNDFD assay predicted total-tract NDF digestibility of HFDCS diets similar to the digestibility observed in vivo, but for LFDCS diets the assay underestimated the digestibility compared with in vivo. When the in vitro and in vivo measurements were compared without intake effect (ad libitum and restricted) considering only diet effect of silage fiber

  17. Autofluorescence spectroscopy of normal and malignant tissues: both in-vivo and ex-vivo measurements in the upper aero-digestive tract and lung tissues

    NASA Astrophysics Data System (ADS)

    A'Amar, Ousama M.; Lignon, Dominique; Menard, O.; Begorre, Henri; Guillemin, Francois H.; Yvroud, Edouard

    1996-04-01

    A spectroscopic system with flexible three optical fiber sensor had been developed to study tissue fluorescence for a clinical use. Autofluorescence spectra at 413 nm and 10 mW excitation light power from different tissues in oral cavity had been measured in vivo in 25 subjects. The correlation coefficient in spectral shape between individual spectra and the mean emission spectrum of each site was about 0.9 and fluorescence intensity variation ranged between 20% and 45% according to the examined site. The variation in fluorescence intensity of the main emission wavelength at about 520 nm between spectra of the lower part of tongue, gingiva, lips, floor of cavity, cheek and palate was not statistically significant. But the spectrum of the upper part of tongue had been characterized by an additional peak around 635 nm. Otherwise, autofluorescence spectra at 410 nm and 0.5 mW excitation light power of 8 carcinoma of buccal and lung tissues were measured. The fluorescence ratio at 520 emission peak between normal tissue and carcinoma was evaluated at a maximum value of 13 for a lung cancer (ex vivo measurement) and a minimum of 3.3 for a cancer of the oro-pharynx (in vivo measurement). On the other hand, a fluorescence peak at 635 nm had characterized the carcinoma of the floor of cavity and the upper part of tongue.

  18. Histopathological changes in the upper digestive tract of pigeons infected with Hadjelia truncata.

    PubMed

    Oryan, Ahmad; Rakhshandehroo, Ehsan; Kamali, S Amir; Taebi Pour, Mohammad Jafar

    2016-09-01

    Thirty-five pigeons from ten different farms in Fars area, southern Iran were submitted for post mortem inspection. Based on the clinical observations and gross pathological examinations, all the birds showed severe weight loss, diarrhea and to some extent ventricular enlargement. Furthermore, all the cases demonstrated large numbers of nematodes attached to the mucosa and submucosa of the ventriculus. Parasitological examinations revealed that the recovered parasites were Hadjelia truncata. The histopathological changes showed necrosis of the mucosal cells with moderate infiltration of lymphocytes, macrophages, heterophils and eosinophils in the lamina properia and muscularis mucosa in the infected animals. Based on the parasitological and pathological findings it can be concluded that the nematode H. truncate could be assigned as a pathogenic agent in the upper tract of pigeons. PMID:27605802

  19. Histopathological changes in the upper digestive tract of pigeons infected with Hadjelia truncata.

    PubMed

    Oryan, Ahmad; Rakhshandehroo, Ehsan; Kamali, S Amir; Taebi Pour, Mohammad Jafar

    2016-09-01

    Thirty-five pigeons from ten different farms in Fars area, southern Iran were submitted for post mortem inspection. Based on the clinical observations and gross pathological examinations, all the birds showed severe weight loss, diarrhea and to some extent ventricular enlargement. Furthermore, all the cases demonstrated large numbers of nematodes attached to the mucosa and submucosa of the ventriculus. Parasitological examinations revealed that the recovered parasites were Hadjelia truncata. The histopathological changes showed necrosis of the mucosal cells with moderate infiltration of lymphocytes, macrophages, heterophils and eosinophils in the lamina properia and muscularis mucosa in the infected animals. Based on the parasitological and pathological findings it can be concluded that the nematode H. truncate could be assigned as a pathogenic agent in the upper tract of pigeons.

  20. Endocannabinoids and the Digestive Tract and Bladder in Health and Disease.

    PubMed

    Izzo, Angelo A; Muccioli, Giulio G; Ruggieri, Michael R; Schicho, Rudolf

    2015-01-01

    Components of the so-called endocannabinoid system, i.e., cannabinoid receptors, endocannabinoids, as well as enzymes involved in endocannabinoid synthesis and degradation, have been identified both in the gastrointestinal and in the urinary tract. Evidence suggests that the endocannabinoid system is implicated in many gastrointestinal and urinary physiological and pathophysiological processes, including epithelial cell growth, inflammation, analgesia, and motor function. A pharmacological modulation of the endocannabinoid system might be beneficial for widespread diseases such as gastrointestinal reflux disease, irritable bowel syndrome, inflammatory bowel disease, colon cancer, cystitis, and hyperactive bladder. Drugs that inhibit endocannabinoid degradation and raise the level of endocannabinoids, non-psychotropic cannabinoids (notably cannabidiol), and palmitoylethanolamide, an acylethanolamide co-released with the endocannabinoid anandamide, are promising candidates for gastrointestinal and urinary diseases. PMID:26408170

  1. Effects of microbial phytase on apparent and standardized total tract digestibility of calcium in calcium supplements fed to growing pigs.

    PubMed

    González-Vega, J C; Walk, C L; Stein, H H

    2015-05-01

    An experiment was conducted to test the hypothesis that differences in the apparent total tract digestibility (ATTD) and standardized total tract digestibility (STTD) of Ca exist among Ca supplements and that inclusion of microbial phytase increases the ATTD and STTD of Ca. One hundred and four growing barrows (average initial BW of 17.73 ± 2.53 kg) were allotted to a randomized complete block design with 13 dietary treatments and 8 pigs per treatment. A basal diet containing corn, cornstarch, potato protein isolate, soybean oil, calcium carbonate, monosodium phosphate, vitamins, and minerals was formulated. Five additional diets were formulated by adding monocalcium phosphate (MCP), dicalcium phosphate (DCP), calcium carbonate, Lithothamnium calcareum Ca, or a high-Ca sugar beet co-product to the basal diet at the expense of cornstarch. Six additional diets that were similar to the previous 6 diets with the exception that they also contained 500 units per kilogram of microbial phytase were also formulated. A Ca-free diet was used to determine basal endogenous losses of Ca. Feces were collected using the marker-to-marker approach. Results indicated that regardless of inclusion of microbial phytase, MCP had the greatest (P < 0.05) ATTD and STTD of Ca. The ATTD and STTD of Ca in DCP were greater (P < 0.05) than in calcium carbonate, L. calcareumC a, or in the sugar beet co-product, but no differences were observed among the ATTD and STTD of Ca in calcium carbonate, L. calcareum Ca, or sugar beet co-product. Inclusion of microbial phytase increased (P < 0.05) the ATTD and STTD of Ca in the diets, but this was not the case in the Ca supplements. Regardless of inclusion of microbial phytase, the ATTD of P was greater ( P< 0.05) in pigs fed basal, MCP, or DCP diets than in pigs fed calcium carbonate, L. calcareum Ca, or the sugar beet co-product, but pigs fed calcium carbonate diets had greater ( P< 0.05) ATTD of P than pigs fed L. calcareumCa or the sugar beet co

  2. Effects of partial replacement of corn and alfalfa silage with tall fescue hay on total-tract digestibility and lactation performance in dairy cows.

    PubMed

    Bender, R W; Lopes, F; Cook, D E; Combs, D K

    2016-07-01

    Our objective was to evaluate the effects of replacing either corn or alfalfa silage with tall fescue hay on total-tract neutral detergent fiber (NDF) digestibility and lactation performance in dairy cows. Twenty-four primiparous (75±35 d in milk) and 40 multiparous (68±19 d in milk) Holstein cows were blocked by parity and randomly assigned to 1 of 4 treatment groups in a pen equipped with 32 feeding gates to record intake by cow. Each gate was randomly assigned to 1 treatment group; thus, each cow had access to all 8 gates within the respective treatment and cow was the experimental unit. Treatments were formulated to replace either corn silage (CS) or alfalfa silage (AS) with tall fescue hay (TF) as follows (DM basis): 33% AS and 67% CS (control; 33AS67CS), 60% TF and 40% AS (60TF40AS), 60% TF and 40% CS (60TF40CS), and 33% TF and 67% CS (33TF67CS). The experiment was a 7-wk continuous lactation trial with a 2-wk covariate period. Milk production did not differ among treatments and averaged 40.4 kg/d. Fat yield and concentration and protein yield and concentration did not differ among treatments and averaged 1.58 kg/d, 3.94%, 1.28 kg/d, and 3.15%, respectively. Dry matter intake was greater for 33AS67CS (24.5 kg/d) compared with 60TF40CS (22.1 kg/d) and 33TF67CS (22.7 kg/d), and tended to be greater than 60TF40AS (23.2 kg/d). In vivo total-tract dry matter digestibility did not differ among treatments and averaged 66.2%. In vivo total-tract NDF digestibility was lower for 33AS67CS (37.8%) compared with 60TF40AS (44.4%) and 33TF67CS (45.3%), and similar to 60TF40CS (42.4%). In vivo total-tract NDF digestibility and an estimate of in situ total-tract NDF digestibility were similar between techniques across all treatment diets (42.3 vs. 42.6%, respectively). Inclusion of tall fescue grass hay increased the total-tract NDF digestibility of the diet and has the potential to replace corn silage and alfalfa silage and maintain milk production if economically feasible

  3. Effects of partial replacement of corn and alfalfa silage with tall fescue hay on total-tract digestibility and lactation performance in dairy cows.

    PubMed

    Bender, R W; Lopes, F; Cook, D E; Combs, D K

    2016-07-01

    Our objective was to evaluate the effects of replacing either corn or alfalfa silage with tall fescue hay on total-tract neutral detergent fiber (NDF) digestibility and lactation performance in dairy cows. Twenty-four primiparous (75±35 d in milk) and 40 multiparous (68±19 d in milk) Holstein cows were blocked by parity and randomly assigned to 1 of 4 treatment groups in a pen equipped with 32 feeding gates to record intake by cow. Each gate was randomly assigned to 1 treatment group; thus, each cow had access to all 8 gates within the respective treatment and cow was the experimental unit. Treatments were formulated to replace either corn silage (CS) or alfalfa silage (AS) with tall fescue hay (TF) as follows (DM basis): 33% AS and 67% CS (control; 33AS67CS), 60% TF and 40% AS (60TF40AS), 60% TF and 40% CS (60TF40CS), and 33% TF and 67% CS (33TF67CS). The experiment was a 7-wk continuous lactation trial with a 2-wk covariate period. Milk production did not differ among treatments and averaged 40.4 kg/d. Fat yield and concentration and protein yield and concentration did not differ among treatments and averaged 1.58 kg/d, 3.94%, 1.28 kg/d, and 3.15%, respectively. Dry matter intake was greater for 33AS67CS (24.5 kg/d) compared with 60TF40CS (22.1 kg/d) and 33TF67CS (22.7 kg/d), and tended to be greater than 60TF40AS (23.2 kg/d). In vivo total-tract dry matter digestibility did not differ among treatments and averaged 66.2%. In vivo total-tract NDF digestibility was lower for 33AS67CS (37.8%) compared with 60TF40AS (44.4%) and 33TF67CS (45.3%), and similar to 60TF40CS (42.4%). In vivo total-tract NDF digestibility and an estimate of in situ total-tract NDF digestibility were similar between techniques across all treatment diets (42.3 vs. 42.6%, respectively). Inclusion of tall fescue grass hay increased the total-tract NDF digestibility of the diet and has the potential to replace corn silage and alfalfa silage and maintain milk production if economically feasible

  4. Stable Isotope Labeled n-Alkanes to Assess Digesta Passage Kinetics through the Digestive Tract of Ruminants

    PubMed Central

    Warner, Daniel; Ferreira, Luis M. M.; Breuer, Michel J. H.; Dijkstra, Jan; Pellikaan, Wilbert F.

    2013-01-01

    We describe the use of carbon stable isotope (13C) labeled n-alkanes as a potential internal tracer to assess passage kinetics of ingested nutrients in ruminants. Plant cuticular n-alkanes originating from intrinsically 13C labeled ryegrass plants were pulse dosed intraruminally in four rumen-cannulated lactating dairy cows receiving four contrasting ryegrass silage treatments that differed in nitrogen fertilization level (45 or 90 kg nitrogen ha−1) and maturity (early or late). Passage kinetics through the gastrointestinal tract were derived from the δ13C (i.e. the ratio 13C:12C) in apparently undigested fecal material. Isotopic enrichment was observed in a wide range of long-chain n-alkanes (C27–C36) and passage kinetics were determined for the most abundant C29, C31 and C33 n-alkanes, for which a sufficiently high response signal was detected by combustion isotope ratio mass spectrometry. Basal diet treatment and carbon chain length of n-alkanes did not affect fractional passage rates from the rumen (K1) among individual n-alkanes (3.71–3.95%/h). Peak concentration time and transit time showed a quantitatively small, significant (p≤0.002) increase with carbon chain length. K1 estimates were comparable to those of the 13C labeled digestible dry matter fraction (3.38%/h; r = 0.61 to 0.71; p≤0.012). A literature review has shown that n-alkanes are not fermented by microorganisms in the rumen and affirms no preferential depletion of 13C versus 12C. Our results suggest that 13C labeled n-alkanes can be used as nutrient passage tracers and support the reliability of the δ13C signature of digestible feed nutrients as a tool to measure nutrient-specific passage kinetics. PMID:24124493

  5. Aero dopes and varnishes

    NASA Technical Reports Server (NTRS)

    Britton, H T S

    1927-01-01

    Before proceeding to discuss the preparation of dope solutions, it will be necessary to consider some of the essential properties which should be possessed of a dope film, deposited in and on the surface of an aero fabric. The first is that it should tighten the material and second it should withstand weathering.

  6. [Cellobiohydrolase Activity in the Digestive Tract of two African Rodent Species the African Grass Rat Arvicanthis niloticus and Vlei Rat Otomys helleri].

    PubMed

    Varshavskiy, A Al; Varshavskiy, A A

    2015-01-01

    Cellobiohydrolase activity (CBHA) of endosymbionts in the digestive tract of two African rodent species differing in its morphology and in feeding specialization--Arvicanthis niloticus and Otomys helleri--has been studied as a characteristic of their physiological and ecological adaptation to phytophagy A statistically significant correlation of CBHA with obesity has been revealed in A. niloticus, with the CBHA level being significantly higher in corpus ceci than in ampulla ceci. The possible morphophysiological and ecological significance of the observed features of symbiotic digestion are discussed. PMID:26349239

  7. Retention of solute and particle markers in the digestive tract of chinchillas (Chinchilla laniger).

    PubMed

    Hagen, K B; Dittmann, M T; Ortmann, S; Kreuzer, M; Hatt, J-M; Clauss, M

    2016-10-01

    The chinchilla (Chinchilla laniger) is a herbivorous hystricomorph South American rodent for which no mean digesta retention times have been reported so far. Six animals (mean body mass ± standard deviation: 513 ± 99 g) on a diet of grass hay and lucerne-based pellets were given a pulse dose of a solute (cobalt-EDTA) and a particle (chromium-mordanted fibre, <2 mm) marker with subsequent frequent faecal collection. Dry matter intake was 45.2 ± 8.0 g/kg(0.75) /day. Mean retention times were 22.2 ± 5.3 h for solutes and 25.4 ± 5.2 h for particles, with the difference being not significant within individuals. This indicates the presence of a 'mucus-trap' colonic separation mechanism, which is in accord with morphological descriptions of the typical colonic furrow in chinchillas. Corresponding to a strategy of colonic digesta separation and caecotroph formation, secondary marker excretion peaks indicated coprophagic events that were spaced approximately 12 h apart. Given that these retention times appear longer than measures reported for rabbits (Oryctolagus cuniculus) or guinea pigs (Cavia procellus), it would be interesting to compare the digestive efficiency of chinchillas on high levels of dietary fibre to other species. PMID:26857102

  8. Deep metabotyping of the murine gastrointestinal tract for the visualization of digestion and microbial metabolism.

    PubMed

    Heinzmann, Silke S; Schmitt-Kopplin, Philippe

    2015-05-01

    Despite the gut's longitudinal specialization for digestion and microbiome organization, most studies focus on the analysis of its end product, feces. To determine the metabolic and physiological functions of different sections of the gut, we aimed to define a comprehensive list of characteristic metabolites for the physiological gut sections and to quantify the selected pathways. We investigated the metabolic composition of seven different gut sections from four C57Bl/6N mice with nontargeted metabolite profiling using high-resolution NMR spectroscopy, which returned a comprehensive metabolite overview with a single analytical measurement per sample. Here we deliver a list of characteristic metabolites, describe metabolite changes along the gut, and highlight the site specificity for selected metabolite pathways. We find that the largest metabolic changes happen in the cecum, where the microbiome produces microbial metabolites. Furthermore, we show the evolution of bile acids along the gut and describe their site-specific conversion. We establish a metabolic basis for future investigations of metabolic perturbations, which can be introduced by dietary challenges or gene knockouts and provide valuable information for tailored study design and targeted sample collection.

  9. Nonruminant Nutrition Symposium: Involvement of gut neural and endocrine systems in pathological disorders of the digestive tract.

    PubMed

    Furness, J B; Poole, D P

    2012-04-01

    The functioning of the gastrointestinal tract is under the control of the most extensive system of peripheral neurons in the body, the enteric nervous system, and the largest endocrine system of the body, the GEP endocrine system. The enteric nervous system in large mammals contains 500 million neurons, and the GEP endocrine system produces more than 30 hormones. Numerous enteric neuropathies affecting both humans and animals have been described and digestive disorders affect commercially important species, such as horses and cattle. The most severe enteric neuropathies (e.g., lethal white syndrome in horses or Hirschsprung's disease in humans) can be fatal. Also, horses with ileus or other digestive disorders are commonly euthanized. In this review we discuss examples of enteric neuropathies that affect agricultural animals and humans: prion disease, postoperative ileus, distal enteric aganglionosis, and infective diarrhea. Enteric neurons and glia are a location of prion proteins and are involved in transmission of the infection from gut to brain and brain to gut. Postoperative ileus is a complex disorder involving the local inhibitory effects of sympathetic nervous system activation and the release of opioids, presumably from enteric neurons. Intestinal inflammation, especially of the external muscle that includes enteric ganglia, also occurs in ileus. Congenital distal bowel aganglionosis, responsible for lethal white syndrome in horses, Hirschsprung's disease in humans, and similar conditions in mice and rats, is a fatal condition if untreated. Mutations of the same genes can cause the condition in each of these species. The only effective current treatment is surgical removal of the aganglionic bowel. Infectious diarrheas involve activation of enteric secretomotor neurons by pathogens and the toxins they produce, which causes substantial fluid loss. Strategies to target enteric neurons in the treatment of secretory diarrheas have not been developed. Disorders

  10. Isolation and identification of a bacterium from marine shrimp digestive tract: A new degrader of starch and protein

    NASA Astrophysics Data System (ADS)

    Li, Jiqiu; Tan, Beiping; Mai, Kangsen

    2011-09-01

    It is a practical approach to select candidate probiotic bacterial stains on the basis of their special traits. Production of digestive enzyme was used as a trait to select a candidate probiotic bacterial strain in this study. In order to select a bacterium with the ability to degrade both starch and protein, an ideal bacterial strain STE was isolated from marine shrimp ( Litopenaeus vannamei) intestines by using multiple selective media. The selected isolate STE was identified on the basis of its morphological, physiological, and biochemical characteristics as well as molecular analyses. Results of degradation experiments confirmed the ability of the selected isolate to degrade both starch and casein. The isolate STE was aerobic, Gram-negative, rod-shaped, motile and non-spore-forming, and had catalase and oxidase activities but no glucose fermentation activity. Among the tested carbon/nitrogen sources, only Tween40, alanyl-glycine, aspartyl-glycine, and glycyl-l-glutamic acid were utilized by the isolate STE. Results of homology comparison analyses of the 16S rDNA sequences showed that the isolate STE had a high similarity to several Pseudoalteromonas species and, in the phylogenetic tree, grouped with P. ruthenica with maximum bootstrap support (100%). In conclusion, the isolate STE was characterized as a novel strain belonging to the genus Pseudoalteromonas. This study provides a further example of a probiotic bacterial strain with specific characteristics isolated from the host gastrointestinal tract.

  11. A Phylogenomic View of Ecological Specialization in the Lachnospiraceae, a Family of Digestive Tract-Associated Bacteria

    PubMed Central

    Meehan, Conor J.; Beiko, Robert G.

    2014-01-01

    Several bacterial families are known to be highly abundant within the human microbiome, but their ecological roles and evolutionary histories have yet to be investigated in depth. One such family, Lachnospiraceae (phylum Firmicutes, class Clostridia) is abundant in the digestive tracts of many mammals and relatively rare elsewhere. Members of this family have been linked to obesity and protection from colon cancer in humans, mainly due to the association of many species within the group with the production of butyric acid, a substance that is important for both microbial and host epithelial cell growth. We examined the genomes of 30 Lachnospiraceae isolates to better understand the origin of butyric acid capabilities and other ecological adaptations within this group. Butyric acid production-related genes were detected in fewer than half of the examined genomes with the distribution of this function likely arising in part from lateral gene transfer (LGT). An investigation of environment-specific functional signatures indicated that human gut-associated Lachnospiraceae possess genes for endospore formation, whereas other members of this family lack key sporulation-associated genes, an observation supported by analysis of metagenomes from the human gut, oral cavity, and bovine rumen. Our analysis demonstrates that adaptation to an ecological niche and acquisition of defining functional roles within a microbiome can arise through a combination of both habitat-specific gene loss and LGT. PMID:24625961

  12. Spread of an Enterococcus faecalis sequence type 6 (CC2) clone in patients undergoing selective decontamination of the digestive tract.

    PubMed

    Muruzábal-Lecumberri, Izaskun; Girbau, Cecilia; Canut, Andrés; Alonso, Rodrigo; Fernández-Astorga, Aurora

    2015-03-01

    Enterococcus faecalis (E. faecalis) is a common cause of nosocomial infection in immunocompromised patients. The presence and dissemination of high-risk clonal complexes, such as CC2, is an ongoing problem in hospitals. The aim of this work was to characterize 24 E. faecalis isolates from ICU patients undergoing selective decontamination of the digestive tract (SDD) by phenotypical (antimicrobial susceptibility) and genotypical (presence of virulence genes, RAPD-PCR and MLST) methods. Our results showed high prevalence of the ST6 E. faecalis clone (91.6%), especially adapted to the hospital environment, with a multidrug resistance pattern and a multitude of putative virulence genes. In addition, ST179 (4.2%) and ST191 (4.2%) were detected. By RAPD-PCR analysis, the 22 isolates identified as ST6 showed six different DNA patterns, while the two remaining isolates, ST179 and ST191, showed two additional profiles. CC2 is a known clonal complex with high adaptability to hospital environment and worldwide distribution. The high prevalence of the ST6 clone in the studied population could be related to the presence of gentamicin in the SDD mixture since most strains were gentamicin resistant. Consequently, strict surveillance should be applied for rapid detection and control of this clone to prevent future spread outside the ICU.

  13. A phylogenomic view of ecological specialization in the Lachnospiraceae, a family of digestive tract-associated bacteria.

    PubMed

    Meehan, Conor J; Beiko, Robert G

    2014-03-01

    Several bacterial families are known to be highly abundant within the human microbiome, but their ecological roles and evolutionary histories have yet to be investigated in depth. One such family, Lachnospiraceae (phylum Firmicutes, class Clostridia) is abundant in the digestive tracts of many mammals and relatively rare elsewhere. Members of this family have been linked to obesity and protection from colon cancer in humans, mainly due to the association of many species within the group with the production of butyric acid, a substance that is important for both microbial and host epithelial cell growth. We examined the genomes of 30 Lachnospiraceae isolates to better understand the origin of butyric acid capabilities and other ecological adaptations within this group. Butyric acid production-related genes were detected in fewer than half of the examined genomes with the distribution of this function likely arising in part from lateral gene transfer (LGT). An investigation of environment-specific functional signatures indicated that human gut-associated Lachnospiraceae possess genes for endospore formation, whereas other members of this family lack key sporulation-associated genes, an observation supported by analysis of metagenomes from the human gut, oral cavity, and bovine rumen. Our analysis demonstrates that adaptation to an ecological niche and acquisition of defining functional roles within a microbiome can arise through a combination of both habitat-specific gene loss and LGT. PMID:24625961

  14. Rifaximin combined with polymyxins: A potential regimen for selective decontamination of multidrug-resistant bacteria in the digestive tract?

    PubMed

    Betts, J W; Phee, L M; Wareham, D W

    2016-03-01

    Selective decontamination of the digestive tract (SDD) using combinations of oral non-absorbable antibiotics has been proposed as a means of preventing multidrug-resistant (MDR) infections. The minimum inhibitory concentrations (MICs) of rifaximin (RIFAX) were determined against 262 Gram-negative and Gram-positive bacterial isolates by broth microtitre assay. Rifampicin (RIF) was used as a comparator in the analysis. Synergistic interactions between RIFAX and polymyxin B (PMB) were assessed by using the chequerboard method and calculating the fractional inhibitory concentration index (FICI). The antimicrobial activities of both RIFAX and RIF were similar with little variation in the overall MIC distributions for Gram-negative non-fermenters and Gram-positive bacteria. However, against Enterobacteriaceae higher MICs (>16mg/L) were observed for RIFAX than for RIF (50% vs 27%). Amongst the 262 isolates tested, 100 could be considered resistant to RIFAX. Overall, the combination of RIFAX and PMB was more active against all of the isolates tested compared with either drug alone, with reductions of 2-11 doubling dilutions in individual MICs. Potent synergy was observed with the RIFAX+PMB combination using FICI criteria (FICI range 0.02-0.5). The data presented here suggest that combination therapy may be significantly more effective against isolates with RIFAX and/or PMB resistance and could be considered as part of a SDD regimen aimed at reducing enteric carriage of MDR pathogens in colonised and infected patients. PMID:27436386

  15. Automated segmentation of upper digestive tract from abdominal contrast-enhanced CT data using hierarchical statistical modeling of organ interrelations

    NASA Astrophysics Data System (ADS)

    Hirayama, S.; Otake, Y.; Okada, T.; Hori, M.; Tomiyama, N.; Sato, Y.

    2016-03-01

    We have been studying the automatic segmentation of multi-organ region from abdominal CT images. In previous work, we proposed an approach using a hierarchical statistical modeling using a relationship between organs. In this paper, we have proposed automatic segmentation of the upper digestive tract from abdominal contrast-enhanced CT using previously segmented multiple organs. We compared segmentation accuracy of the esophagus, stomach and duodenum between our proposed method using hierarchical statistical modeling and a conventional statistical atlas method. Additionally, preliminary experiment was performed which added the region representing gas to the candidate region at the segmentation step. The segmentation results were evaluated quantitatively by Dice coefficient, Jaccard index and the average symmetric surface distance of the segmented region and correct region data. Percentage of the average of Dice coefficient of esophagus, stomach and duodenum were 58.7, 68.3, and 38.6 with prediction-based method and 23.7, 51.1, and 24.4 with conventional atlas method.

  16. Histology assessment of bipolar coagulation and argon plasma coagulation on digestive tract

    PubMed Central

    Garrido, Teresa; Baba, Elisa R; Wodak, Stephanie; Sakai, Paulo; Cecconello, Ivan; Maluf-Filho, Fauze

    2014-01-01

    AIM: To analyze the effect of bipolar electrocoagulation and argon plasma coagulation on fresh specimens of gastrointestinal tract. METHODS: An experimental evaluation was performed at Hospital das Clinicas of the University of São Paulo, on 31 fresh surgical specimens using argon plasma coagulation and bipolar electrocoagulation at different time intervals. The depth of tissue damage was histopathologically analyzed by single senior pathologist unaware of the coagulation method and power setting applied. To analyze the results, the mucosa was divided in superficial mucosa (epithelial layer of the esophagus and superficial portion of the glandular layer of the stomach and colon) intermediate mucosa (until the lamina propria of the esophagus and until the bottom of the glandular layer of the stomach and colon) and muscularis mucosa. Necrosis involvement of the layers was compared in several combinations of power and time interval. RESULTS: Involvement of the intermediate mucosa of the stomach and of the muscularis mucosa of the three organs was more frequent when higher amounts of energy were used with argon plasma. In the esophagus and in the colon, injury of the intermediate mucosa was frequent, even when small amounts of energy were used. The use of bipolar electrocoagulation resulted in more frequent involvement of the intermediate mucosa and of the muscularis mucosa of the esophagus and of the colon when higher amounts of energy were used. In the stomach, these involvements were rare. The risk of injury of the muscularis propria was significant only in the colon when argon plasma coagulation was employed. CONCLUSION: Tissue damage after argon plasma coagulation is deeper than bipolar electrocoagulation. Both of them depend on the amount of energy used. PMID:25031789

  17. Clinical significance of CA19-9 in diagnosis of digestive tract tumors

    PubMed Central

    Zhao, Ji-Zong; Wu, Bo-Heng

    1997-01-01

    AIM: To evaluate the clinical value of CA19-9 in diagnosing and differentiating gastrointestinal tumors and in monitoring patients treated surgically. METHODS: Patients with gastric cancer (n = 70), colorectal cancer (n = 90), pancreatic cancer (n = 7), esophageal cancer (n = 10) and benign disorders (n = 30), and normal adults (n = 111; used as healthy controls), were studied. Fasting blood samples were obtained from each study participant. The serum CA19-9 concentration was measured with radioimmunoassay. RESULTS: The mean CA19-9 level was significantly higher in patients with gastric cancer (170.69 ± 91.45 kU/L) and patients with colorectal cancer (87.21 ± 39.55 kU/L) than in the healthy controls (11.254 ± 6.00 kU/L). Compared with the healthy controls, the CA19-9 level was also much higher in patients with pancreatic cancer (1266.58 ± 521.31 kU/L) (P < 0.01). However, the CA19-9 concentrations in patients with non-recurrent gastric cancer (12.63 ± 3.62 kU/L), colorectal cancer (14.14 ± 3.26 kU/L) and benign disorders (14.23 ± 2.60 kU/L) were statistically similar to those in the healthy controls (P > 0.05). The demarcation value of CA19-9 between negative and positive was < 31.0 kU/L. The sensitivity of CA19-9 for gastric, colorectal, pancreatic and esophageal cancers and for gastrointestinal benign disorders was 47.3%, 50.0%, 83.3%, 20.0% and 0%, respectively. The specificity of CA19-9 for digestive system malignant diseases was 100% for all. PMID:27053885

  18. Occurrence, absorption and metabolism of short chain fatty acids in the digestive tract of mammals.

    PubMed

    Bugaut, M

    1987-01-01

    Short chain fatty acids (SCFA) also named volatile fatty acids, mainly acetate, propionate and butyrate, are the major end-products of the microbial digestion of carbohydrates in the alimentary canal. The highest concentrations are observed in the forestomach of the ruminants and in the large intestine (caecum and colon) of all the mammals. Butyrate and caproate released by action of gastric lipase on bovine milk triacylglycerols ingested by preruminants or infants are of nutritional importance too. Both squamous stratified mucosa of rumen and columnar simple epithelium of intestine absorb readily SCFA. The mechanisms of SCFA absorption are incompletely known. Passive diffusion of the unionized form across the cell membrane is currently admitted. In the lumen, the necessary protonation of SCFA anions could come first from the hydration of CO2. The ubiquitous cell membrane process of Na+-H+ exchange can also supply luminal protons. Evidence for an acid microclimate (pH = 5.8-6.8) suitable for SCFA-protonation on the surface of the intestinal lining has been provided recently. This microclimate would be generated by an epithelial secretion of H+ ions and would be protected by the mucus coating from the variable pH of luminal contents. Part of the absorbed SCFA does not reach plasma because it is metabolized in the gastrointestinal wall. Acetate incorporation in mucosal higher lipids is well-known. However, the preponderant metabolic pathway for all the SCFA is catabolism to CO2 except in the rumen wall where about 80% of butyrate is converted to ketone bodies which afterwards flow into bloodstream. Thus, SCFA are an important energy source for the gut mucosa itself.

  19. Persistence of antibiotic-resistant and -sensitive Proteus mirabilis strains in the digestive tract of the housefly (Musca domestica) and green bottle flies (Calliphoridae).

    PubMed

    Wei, Ting; Miyanaga, Kazuhiko; Tanji, Yasunori

    2014-10-01

    Synanthropic flies have been implicated in the rapid dissemination of antibiotic-resistant bacteria and resistance determinants in the biosphere. These flies stably harbor a considerable number of bacteria that exhibit resistance to various antibiotics, but the mechanisms underlying this phenomenon remain unclear. In this study, we investigated the persistence of antibiotic-resistant bacteria in the digestive tract of houseflies and green bottle flies, using Proteus mirabilis as a model microorganism. One resistant strain carried the blaTEM and aphA1 genes, and another carried a plasmid containing qnrD gene. Quantitative PCR and 454 pyrosequencing were used to monitor the relative abundance of the Proteus strains, as well as potential changes in the overall structure of the whole bacterial community incurred by the artificial induction of Proteus cultures. Both antibiotic-resistant and -sensitive P. mirabilis strains persisted in the fly digestive tract for at least 3 days, and there was no significant difference in the relative abundance of resistant and sensitive strains despite the lower growth rate of resistant strains when cultured in vitro. Therefore, conditions in the fly digestive tract may allow resistant strains to survive the competition with sensitive strains in the absence of antibiotic selective pressure. The composition of the fly-associated bacterial community changed over time, but the contribution of the artificially introduced P. mirabilis strains to these changes was not clear. In order to explain these changes, it will be necessary to obtain more information about bacterial interspecies antagonism in the fly digestive tract.

  20. The site of net absorption of Ca from the intestinal tract of growing pigs and effect of phytic acid, Ca level and Ca source on Ca digestibility.

    PubMed

    González-Vega, J Caroline; Walk, Carrie L; Liu, Yanhong; Stein, Hans H

    2014-01-01

    An experiment was conducted to test the hypothesis that the standardised digestibility of Ca in calcium carbonate and Lithothamnium calcareum Ca is not different regardless of the level of dietary Ca, and that phytic acid affects the digestibility of Ca in these two ingredients to the same degree. The objectives were to determine where in the intestinal tract Ca absorption takes place and if there are measurable quantities of basal endogenous Ca fluxes in the stomach, small intestine or large intestine. Diets contained calcium carbonate or L. calcareum Ca as the sole source of Ca, 0% or 1% phytic acid and 0.4% or 0.8% Ca. A Ca-free diet was also formulated and used to measure endogenous fluxes and losses of Ca. Nine growing pigs (initial body weight 23.8 ± 1.3 kg) were cannulated in the duodenum and in the distal ileum, and faecal, ileal and duodenal samples were collected. Duodenal endogenous fluxes of Ca were greater (p < 0.05) than ileal endogenous fluxes and total tract endogenous losses of Ca, but ileal endogenous fluxes were less (p < 0.05) than total tract endogenous losses. Standardised digestibility of Ca was not affected by the level of phytic acid, but decreased (p < 0.05) as Ca level increased in L. calcareum Ca diets, but that was not the case if calcium carbonate was the source of Ca (interaction, p < 0.05). The standardised duodenal digestibility (SDD), standardised ileal digestibility (SID) and standardised total tract digestibility (STTD) of Ca were not different if calcium carbonate was the source of dietary Ca. However, the STTD of Ca in L. calcareum Ca was greater (p < 0.05) than the SID and SDD of Ca. The SDD, SID and STTD of Ca in calcium carbonate were greater (p < 0.05) than those of L. calcareum Ca. In conclusion, under the conditions of this experiment, standardised digestibility of Ca is not affected by the level of phytic acid, but may be affected by dietary Ca level depending on the Ca source. Calcium from calcium carbonate is mostly

  1. Aero/structural tailoring of engine blades (AERO/STAEBL)

    NASA Technical Reports Server (NTRS)

    Brown, K. W.

    1988-01-01

    This report describes the Aero/Structural Tailoring of Engine Blades (AERO/STAEBL) program, which is a computer code used to perform engine fan and compressor blade aero/structural numerical optimizations. These optimizations seek a blade design of minimum operating cost that satisfies realistic blade design constraints. This report documents the overall program (i.e., input, optimization procedures, approximate analyses) and also provides a detailed description of the validation test cases.

  2. Dietary flavonoid intake and the risk of digestive tract cancers: a systematic review and meta-analysis

    PubMed Central

    Bo, Yacong; Sun, Jinfeng; Wang, Mengmeng; Ding, Jizhe; Lu, Quanjun; Yuan, Ling

    2016-01-01

    Several epidemiological studies have investigated the association between dietary flavonoid intake and digestive tract cancers risk; however, the results remain inconclusive. The aim of our study was to evaluate this association. PubMed and the Web of Knowledge were searched for relevant publications from inception to October 2015. The risk ratio (RR) or odds ratio (OR) with the 95% confidence interval (95% CI) for the highest versus the lowest categories of flavonoid intake were pooled using a fixed-effects model. A total of 15 articles reporting 23 studies were selected for the meta-analysis. In a comparison of the highest versus the lowest categories of dietary flavonoid intake, we found no significant association between flavonoid intake and oesophageal cancer (OR = 0.91, 95% CI = 0.75–1.10; I2 = 0.0%), colorectal cancer (OR = 1.02, 95% CI = 0.92–1.14, I2 = 36.2%) or gastric cancer (OR = 0.88; 95% CI = 0.74–1.04, I2 = 63.6%). The subgroup analysis indicated an association between higher flavonoid intake and a decreased risk of gastric cancer in the European population (OR = 0.78, 95% CI = 0.62–0.97). In conclusion, the results of this meta-analysis do not strongly support an association between dietary flavonoid intake and oesophageal or colorectal cancer. Furthermore, the subgroup analysis suggested an association between higher dietary flavonoid intake and decreased gastric cancer risk in European population. PMID:27112267

  3. The effect of diet on ontogenic development of the digestive tract in juvenile reared long snout seahorse Hippocampus guttulatus.

    PubMed

    Palma, J; Bureau, D P; Andrade, J P

    2014-06-01

    Ontogenetic development of the digestive tract and associated organs in long snout seahorse Hippocampus guttulatus juveniles was morphologically and histologically examined from the time of release from the male's pouch until 72 h after the first meal. When released from the male's pouch, juvenile seahorses are small adult replicates. This means that unlike other teleost fish larvae, the first developmental phase has already taken place, and juveniles are morphologically prepared and able to feed on live prey immediately following parturition. At this stage, the buccopharynx, oesophagus, and intestine already appear to be fully developed. The intestine is divided into the midgut and hindgut by an intestinal valve, and intestinal villi are visible in the midgut. When fed with DHA-Selco(®) enriched Artemia, H. guttulatus juveniles developed a severe condition of overinflation of the gas bladder. The continuous overinflation of the gas bladder forced air into the gut (48 h after the first meal), resulting in overinflation of both the gut and the gas bladder (72 h after the first meal), and death occurred within 120 h after the first meal. When fed natural copepods, H. guttulatus juveniles continued a normal feeding activity with no signs of intestinal disorders, and the gas bladder and intestine maintained their normal shape. This is the first study to positively associate gas bladder overinflation of juvenile seahorses with nutritionally unbalanced diets, and not to gas supersaturation alone. It is therefore necessary to develop more adequate feed and/or enrichment products to improve the survival of juvenile seahorses in captivity.

  4. The arylalkylamine-N-acetyltransferase (AANAT) acetylates dopamine in the digestive tract of goldfish: a role in intestinal motility.

    PubMed

    Nisembaum, Laura Gabriela; Tinoco, A B; Moure, A L; Alonso Gómez, A L; Delgado, M J; Valenciano, A I

    2013-05-01

    Melatonin has been found in the digestive tract of many vertebrates. However, the enzymatic activity of the arylalkylamine-N-acetyltransferase (AANAT) and the hydroxindole-O-methyltransferase (HIOMT), the last two enzymes of melatonin biosynthesis, have been only measured in rat liver. Therefore, the first objective of the present study is to investigate the functionality of these enzymes in the liver and gut of goldfish, analyzing its possible daily changes and comparing its catalytic properties with those from the retina isoforms. The daily rhythms with nocturnal acrophases in retinal AANAT and HIOMT activities support their role in melatonin biosynthesis. In foregut AANAT activity also show a daily rhythm while in liver and hindgut significant but not rhythmic levels of AANAT activity are found. HIOMT activity is not detected in any of these peripheral tissues suggesting an alternative role for AANAT besides melatonin synthesis. The failure to detect functional HIOMT activity in both, liver and gut, led us to investigate other physiological substrates for the AANAT, as dopamine, searching alternative roles for this enzyme in the goldfish gut. Dopamine competes with tryptamine and inhibits retinal, intestinal and hepatic N-acetyltryptamine production, suggesting that the active isoform in gut is AANAT1. Besides, gut and liver produces N-acetyldopamine in presence of acetyl coenzyme-A and dopamine. This production is not abolished by the presence of folic acid (arylamine N-acetyltransferase inhibitor) in any studied tissue, but a total inhibition occurs in the presence of CoA-S-N-acetyltryptamine (AANAT inhibitor) in liver. Therefore, AANAT1 seems to be an important enzyme in the regulation of dopamine and N-acetyldopamine content in liver. Finally, for the first time in fish we found that dopamine, but not N-acetyldopamine, regulates the gut motility, underlying the broad physiological role of AANAT in the gut.

  5. Bacterial communities associated with the digestive tract of the predatory ground beetle, Poecilus chalcites, and their response to laboratory rearing and antibiotic treatment

    SciTech Connect

    Michael Lehman

    2008-06-01

    Ground beetles such as Poecilus chalcites (Coleoptera: Carabidae) are beneficial insects in agricultural systems where they contribute to the control of insect and weed pests. We assessed the complexity of bacterial communities occurring in the digestive tracts of field-collected P. chalcites using terminal restriction fragment length polymorphism analyses of polymerase chain reaction-amplified 16S rRNA genes. Bacterial identification was performed by the construction of 16S rRNA gene clone libraries and sequence analysis. Intestinal bacteria in field-collected beetles were then compared to those from groups of beetles that were reared in the lab on an artificial diet with and without antibiotics. Direct cell counts estimated 1.5 × 10S bacteria per milliliter of gut. The digestive tract of field-collected P. chalcites produced an average of 4.8 terminal restriction fragments (tRF) for each beetle. The most abundant clones were affiliated with the genus Lactobacillus, followed by the taxa Enterobacteriaceae, Clostridia, and Bacteriodetes. The majority of the sequences recovered were closely related to those reported from other insect gastrointestinal tracts. Lab-reared beetles produced fewer tRF, an average of 3.1 per beetle, and a reduced number of taxa with a higher number of clones from the family Enterobacteriaceae compared to the field-collected beetles. Antibiotic treatment significantly (p < 0.05) reduced the number of tRF per beetle and selected for a less diverse set of bacterial taxa. We conclude that the digestive tract of P. chalcites is colonized by a simple community of bacteria that possess autochthonous characteristics. Laboratory-reared beetles harbored the most common bacteria found in field-collected beetles, and these bacterial communities may be manipulated in the laboratory with the addition of antibiotics to the diet to allow study of functional roles.

  6. Comparison of different digestive tract models for estimating bioaccessibility of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) from red slag 'Kieselrot'.

    PubMed

    Wittsiepe, J; Schrey, P; Hack, A; Selenka, F; Wilhelm, M

    2001-03-01

    'Kieselrot' (red slag), a highly PCDD/F-contaminated leaching residue from a copper production process, has been used as surface layer for more than 1,000 sports fields, playgrounds and pavements in Germany and neighbouring countries. Children can ingest this material directly by hand-to-mouth activities or soil-pica behaviour. Furthermore secondary contamination of farm land or kitchen gardens by drift of red slag dust may lead to an enrichment of PCDD/F within the food-chain. PCDD/F can be mobilized from contaminated materials by digestive juices and thus become bioaccessible for intestinal absorption. Two different digestive tract models were used to estimate the bioaccessibility of PCDD/F from red slag and to study the influence of food material on the mobilization of the contaminants. The bioaccessibility of PCDD/F from red slag depends on the charge of red slag material used, the bile content of the intestinal juice and on the presence of lipophilic foodstuffs. A low bioaccessibility of less than 5% was found when using a digestive tract model with a low bile content and in absence of food material. The bioaccessibility was estimated to be more than 60% when using a model with a higher bile content and in the presence of whole milk powder. A low bioaccessibility of PCDD/F from red slag in general--as assumed until now and mentioned in legal provision--was not confirmed by our study. Considering observations for the different homologue groups it is obvious that bioaccessibility is the first of several important steps to estimate human health risks arising from contaminated materials. In case red slag contaminated with PCDD/F their absorption rate in the digestive tract and/or metabolism might be at least just like important.

  7. A cooperative study on the standardized total-tract digestible phosphorus requirement of twenty-kilogram pigs.

    PubMed

    Adeola, O; Azain, M J; Carter, S D; Crenshaw, T D; Estienne, M J; Kerr, B J; Lindemann, M D; Maxwell, C V; Miller, P S; Shannon, M C; van Heugten, E

    2015-12-01

    A cooperative study comprising growth performance, bone mineralization, and nutrient balance experiments was conducted at 11 stations to determine the standardized total-tract digestible (STTD) P requirement of 20-kg pigs using broken-line regression analysis. Monocalcium phosphate and limestone were added to a corn-soybean meal-based diet at the expense of cornstarch to establish 6 concentrations of STTD P from 1.54 to 5.15 g/kg in increments of 0.62 g/kg at a constant Ca:total P of 1.52:1.0. Diets were fed to 936 pigs (average initial BW of 19 kg) in 240 pens for 20 replicate pens of barrows and 20 replicate pens of gilts per diet. As STTD P increased from 1.54 to 5.15 g/kg of the diet for d 0 to 14, 14 to 28, and 0 to 28, the ADG, ADFI, and G:F increased ( < 0.01). Barrows gained and ate more ( < 0.05) than gilts during d 14 to 28 and 0 to 28. There was no interaction between sex and STTD P concentration for any of the growth performance response criteria. There were both linear and quadratic increases ( < 0.05) in mineral density and content of ash, Ca, and P in the femur expressed as a percentage of dry, fat-free metacarpal as dietary STTD P increased. Furthermore, the maximum load of the femur and mineral density and content and maximum load as well as the Ca and P expressed as a percentage of metacarpal ash linearly increased ( < 0.01) with increasing dietary concentrations of STTD P. There were both linear and quadratic increases ( < 0.01) in apparent digestibility and retention of P with increasing concentrations of STTD P in the diets. Digestibility and retention of Ca linearly ( < 0.01) increased with increasing dietary concentrations of STTD P. Breakpoints determined from nonlinear broken-line regression analyses revealed estimates of 4.20 ± 0.102, 3.20 ± 0.036, or 3.87 ± 0.090 g/kg for ADG during d 0 to 14, 14 to 28, or 0 to 28, respectively. Corresponding estimates using G:F as the response criterion were 4.34 ± 0.146, 3.38 ± 0.139, or 4.08 ± 0

  8. Effects of day of gestation and feeding regimen in Holstein × Gyr cows: I. Apparent total-tract digestibility, nitrogen balance, and fat deposition.

    PubMed

    Rotta, P P; Filho, S C Valadares; Gionbelli, T R S; Costa E Silva, L F; Engle, T E; Marcondes, M I; Machado, F S; Villadiego, F A C; Silva, L H R

    2015-05-01

    This study investigated how feeding regimen (FR) alters apparent total-tract digestibility, performance, N balance, excretion of purine derivatives, and fat deposition in Holstein × Gyr cows at different days of gestation (DG). Forty-four pregnant multiparous Holstein × Gyr cows with an average initial body weight of 480±10.1 kg and an initial age of 5±0.5 yr old were allocated to 1 of 2 FR: ad libitum (AL; n=20) and maintenance level (ML; n=24). Maintenance level was considered to be 1.15% of body weight on a dry matter (DM) basis and met 100% of the energy requirements, whereas AL provided 190% of total net energy requirements. Data for hot and cold carcass dressing, fat deposition, average daily gain, empty body gain, and average daily gain without the gravid uterus were analyzed as a 4×2 factorial design. Intake, apparent total-tract digestibility, N balance, urinary concentration of urea, and purine derivatives data were analyzed as repeated measurements taken over the 28-d period (122, 150, 178, 206, 234, and 262 d of gestation). Cows were individually fed a corn silage-concentrate based diet composed of 93% roughage and 7% concentrate (DM basis) as a total mixed ration. Pregnant cows were slaughtered on 4 different DG: 139 (n=11), 199 (n=11), 241 (n=11), and 268 d (n=11). Overall, DM intake decreased as DG increased. This decrease observed in DM intake may be associated with the reduction in ruminal volume caused by the rapid increase in fetal size during late gestation. We observed an interaction for DM and organic matter apparent total-tract digestibility between FR and DG; at 150, 178, and 206 d of gestation, ML-fed cows had greater DM and organic matter apparent total-tract digestibility values than AL-fed cows. Rib fat thickness, mesentery, and kidney, pelvic, and heart fat were greater in AL-fed than in ML-fed cows at all DG, with the exception of rib fat thickness on d 139. Ad libitum-fed cows excreted more N in their feces and urine compared

  9. Responses of the digestive tract of the omnivorous northern brown bandicoot, Isoodon macrourus (Marsupialia: Peramelidae), to plant- and insect-containing diets.

    PubMed

    McClelland, K L; Hume, I D; Soran, N

    1999-09-01

    The gastrointestinal tract of omnivores such as bandicoots (Marsupialia: Peramelidae) must be able to process foods as different as invertebrates, fungi and plant material. We studied the mechanisms involved in the utilisation by captive northern brown bandicoots (Isoodon macrourus) of insect larvae and milled lucerne (Medicago sativa) hay incorporated into a basal diet of a commercial small carnivore mix. Animals on the plant-basal mix digested less dry matter, energy, lipid, fibre and total nitrogen, but consumed 79% more dry matter than those on the insect-basal mix. Consequently intake of digestible energy (i.e. energy absorbed) was not significantly different between diets. Mean retention time (MRT, the mean time a marker remains in the tract) of a large particle marker was shorter on the plant-basal mix, reflecting its higher intake, but MRT of a solute marker was not significantly different between diets. Consequently the solute marker was retained longer than the particle marker on the plant-basal mix, indicating selective retention of solutes and very small particles in the caecum on this diet. This was confirmed by a higher proportion of small particles in the caecum than the distal colon of road-killed I. macrourus. Thus the main responses by I. macrourus to the plant-basal mix appeared to be an increase in gastrointestinal tract capacity (from radiographic evidence), selective retention of solutes and very small particles in the caecum, and facilitated passage of less tractable large particles through the colon. As a consequence, food intake was higher on the plant-basal mix, which compensated for its lower digestibility, and intake of digestible energy was similar to that on the insect-basal mix. This considerable flexibility of the morphologically rather simple digestive tract of northern brown bandicoots helps to explain their ability to cope with naturally variable diets consisting of mainly invertebrates in summer to much more plant and fungal

  10. Casein Supplementation Does Not Affect the Estimates of True Total Tract Digestibility of Phosphorus in Soybean Meal for Growing Pigs Determined by the Regression Method

    PubMed Central

    Liu, J. B.; Adeola, O.

    2016-01-01

    Forty-eight barrows with an average initial body weight of 25.5±0.3 kg were assigned to 6 dietary treatments arranged in a 3×2 factorial of 3 graded levels of P at 1.42, 2.07, or 2.72 g/kg, and 2 levels of casein at 0 or 50 g/kg to compare the estimates of true total tract digestibility (TTTD) of P in soybean meal (SBM) for pigs fed diets with or without casein supplementation. The SBM is the only source of P in diets without casein, and in the diet with added casein, 1.0 to 2.4 g/kg of total dietary P was supplied by SBM as dietary level of SBM increased. The experiment consisted of a 5-d adjustment period and a 5-d total collection period with ferric oxide as a maker to indicate the initiation and termination of fecal collection. There were interactive effects of casein supplementation and total dietary P level on the apparent total tract digestibility (ATTD) and retention of P (p<0.05). Dietary P intake, fecal P output, digested P and retained P were increased linearly with graded increasing levels of SBM in diets regardless of casein addition (p<0.01). Compared with diets without casein, there was a reduction in fecal P in the casein-supplemented diets, which led to increases in digested P, retained P, ATTD, and retention of P (p<0.01). Digested N, ATTD of N, retained N, and N retention were affected by the interaction of casein supplementation and dietary P level (p<0.05). Fecal N output, urinary N output, digested N, and retained N increased linearly with graded increasing levels of SBM for each type of diet (p<0.01). The estimates of TTTD of P in SBM, derived from the regression of daily digested P against daily P intake, for pigs fed diets without casein and with casein were calculated to be 37.3% and 38.6%, respectively. Regressing daily digested N against daily N intake, the TTTD of N in SBM were determined at 94.3% and 94.4% for diets without casein and with added casein, respectively. There was no difference in determined values of TTTD of P or N in

  11. Exogenous and endogenous contributions to nitrogen fluxes in the digestive tract of pigs fed a casein diet. III. Recycling of endogenous nitrogen.

    PubMed

    Souffrant, W B; Rérat, A; Laplace, J P; Darcy-Vrillon, B; Köhler, R; Corring, T; Gebhardt, G

    1993-01-01

    The aim of the present study was to measure the incorporation of infused 15N in blood fractions, urine, digesta, faeces and in the exocrine pancreatic and biliary secretions, in order to estimate the endogenous part of nitrogen in the ileal digesta and in the faeces of pigs fed a casein diet and to calculate the total endogenous nitrogen secretion as well as its recycling in the digestive tract. For 8 d 11 Large White female pigs (50.1 +/- 1.8 kg) received a continuous infusion of L-[15N]leucine via a catheter in the jugular vein. The 15N-enrichment was measured in several fractions. The 15N-level of the pancreatic juice was higher than that in the biliary secretion, TCA-blood fractions, and urine during the whole experimental period. Using the 15N-isotope dilution method it was found that casein was completely digested up to the terminal ileum and that all the nitrogen in the ileal digesta was of endogenous origin. The total endogenous secretion was estimated at approximately 11 g N/d. The reabsorption of endogenous nitrogen amounted to 79% up to the end of the small intestine and 88% over the whole digestive tract. PMID:8240681

  12. Some morphological, biochemical and immunological blood parameters in European bison with or without lesions in the digestive, respiratory, urinary and reproductive tracts.

    PubMed

    Anusz, K; Kita, J; Zaleska, M; Salwa, A; Malicka, E; Bielecki, W; Osińska, B

    2007-01-01

    Ninety-seven bison (39 males and 58 females) were culled out during three successive winter seasons. No infection with BHV-1 and BHV-5 or other viruses was detected by PCR and SN methods. Advanced pathological lesions observed in males exhibiting symptoms of posthitis/balanoposthitis are probably due to secondary infection by microorganisms present in the prepuce (Corynebacterium spp., Bacillus spp., Fusobacterium necrophorum, Staphylococcus spp. (coagulase negative) and Staphylococcus hyicus). Histopathological examinations of sections from prepuce and lips of pudendum showed the presence of Onchocercinae nematode (Onchocerca sp.). A comparison of biochemical and morphological blood parameters in the bison with or without lesions in the digestive (presence of parasites), respiratory, urinary and reproductive tracts revealed that the most variable parameter during reproductive organ disorder is the leukocyte count, while disorders in the urinary and digestive tracts coincided with the age of animals. In cases of digestive disorder most changes were observed in the number of neutrophils and concentration of urea. The number of red blood cells, monocytes, the level of alkaline phosphatase (AP) and hematocrit negatively correlated with age. Negative correlation was also observed between the number of neutrophils, level of creatinine and lymphocyte proliferation index. However, positive correlation was seen between erythrocyte sedimentation rate (Spearman's correlation coefficient), level of alanine aminotransferase (ALT) and protein, and age of the bison. Positive correlation was also observed between the lymphocyte count and lymphocyte proliferation index. The attempt to determine the reference values for blood biochemical and morphological parameters showed similarities to those of cattle. PMID:17937185

  13. Microtus species as new herbivorous laboratory animals: reproduction; bacterial flora and fermentation in the digestive tracts; and nutritional physiology.

    PubMed

    Kudo, H; Oki, Y

    1984-05-01

    In a study of the possible introduction of Japanese field vole (Microtus montebelli ) and Hungarian voles (M. arvalis) as herbivorous experimental animals, the following biological characteristics were investigated: breeding and reproductive performance; bacterial flora and fermentation in the digestive tracts; and nutritional physiology. The animals are polyestrus , show postpartum estrus on the day of parturition, and there is little or no delay in implantation due to lactation, especially in M. arvalis. On examination of vaginal smears, Japanese field vole did not show any definite pattern, whereas most Hungarian voles showed 6- to 18- day cycles. From the esophageal sac of voles fed rations with a high fiber content, cellulolytic bacteria similar to Ruminococcus albus, Ruminococcus flavefaciens , and Bacteroides succinogenes were isolated. More than 1 000 000/g anaerobic bacteria were present in the esophageal sac and the pattern and the types of bacteria resembled those found in the rumen. Gastric fermentation took place in the esophageal sac. The pH and total VFAs were much smaller in the fundic and pyloric regions of the stomach than in the esophageal sac. Acetic and lactic acids were the major fermentation products in the esophageal sac. Following deficiency or lowering of the cellulose decomposing abilities, a decrease of VFAs and an increase in lactic acid production in the esophageal sac were observed. These effects resulted in high glucose, FFA and ketone bodies in the blood, and a higher incidence of glucosuria. Diabetes induced by administrations of drugs such as alloxan, streptozotocin and phloridzin were compared using Microtus and mice. Microtus had low sensitivity to alloxan but high sensitivity to streptozotocin. The influence of monensin on Microtus was also investigated by using diets containing 20 and 80 mg/kg monensin. Diets containing 80 mg/kg monensin led to 50 % mortality in 7 weeks and growth was hindered. Gas production from the

  14. The appearance of re-cycled urea in the digestive tract of goats during the final third of a once daily feeding of a low-protein ration.

    PubMed

    Obara, Y; Shimbayashi, K

    1980-11-01

    1. An experiment was carried out with goats fed on a low-protein ration to clarify the importance of the rumen and significance of saliva in the appearance of re-cycled urea in the digestive tract during the final third of a once daily feeding regimen. The isotope-dilution method with [15N]urea and 15NH4Cl was used. 2. When the serum urea level was 58 mg N/l, the amount of urea transferred from the blood urea pool to the rumen ammonia pool was 48.6 mg N/h, which was estimated to be approximately 43% of the total amount of urea having appeared in the NH3 pool of the digestive tract. When the serum urea level was 106 mg N/l, the corresponding amount of NH3 was 77.7 mg N/h, which was estimated to be approximately 46% of this total amount. 3. The amount of saliva secreted was measured directly by the oesophageal fistula method. Salivary secretion serves as a mode of transfer of blood urea to the rumen NH3 pool. Then the ratio, salivary secretion:diffusion through the rumen wall during the final third of the cycle was calculated to be 1:4-1:6. 4. In goats fed on a low-protein diet, the rumen is an important site of appearance of blood urea in the digestive tract. It was verified that the principal mode of transfer of blood urea to the rumen was the direct diffusion through the wall of the rumen.

  15. Biodistribution and stability of CdSe core quantum dots in mouse digestive tract following per os administration: Advantages of double polymer/silica coated nanocrystals

    SciTech Connect

    Loginova, Y.F.; Dezhurov, S.V.; Zherdeva, V.V.; Kazachkina, N.I.; Wakstein, M.S.; Savitsky, A.P.

    2012-03-02

    Highlights: Black-Right-Pointing-Pointer New QDs coated with combination of polythiol ligands and silica shell were synthesized. Black-Right-Pointing-Pointer We examine the QDs stability in digestive tract of mice after per os administration. Black-Right-Pointing-Pointer The polymer/silica shell prevents QDs degradation and fluorescence quenching in vivo. -- Abstract: CdSe-core, ZnS-capped semiconductor quantum dots (QDs) are of great potential for biomedical applications. However, applications in the gastrointestinal tract for in vivo imaging and therapeutic purposes are hampered by their sensitivity to acidic environments and potential toxicity. Here we report the use of coatings with a combination of polythiol ligands and silica shell (QDs PolyT-APS) to stabilize QDs fluorescence under acidic conditions. We demonstrated the stability of water-soluble QDs PolyT-APS both in vitro, in strong acidic solutions, and in vivo. The biodistribution, stability and photoluminescence properties of QDs in the gastrointestinal tract of mice after per os administration were assessed. We demonstrated that QDs coated with current traditional materials - mercapto compounds (QDs MPA) and pendant thiol group (QDs PolyT) - are not capable of protecting QDs from chemically induced degradation and surface modification. Polythiol ligands and silica shell quantum dots (QDs PolyT-APS) are suitable for biological and biomedical applications in the gastrointestinal tract.

  16. Effects of flaxseed, raw soybeans and calcium salts of fatty acids on apparent total tract digestibility, energy balance and milk fatty acid profile of transition cows.

    PubMed

    Gandra, J R; Mingoti, R D; Barletta, R V; Takiya, C S; Verdurico, L C; Freitas, J E; Paiva, P G; Jesus, E F; Calomeni, G D; Rennó, F P

    2016-08-01

    Oilseeds offer some protection to the access of ruminal microorganisms and may be an alternative to calcium salts of fatty acids (FA), which are not fully inert in the ruminal environment. This study aimed to evaluate the effects of different sources of FA supplementation on apparent total tract nutrient digestibility, milk yield and composition, and energy balance (EB) of cows during the transition period and early lactation. We compared diets rich in C18:2 and C18:3 FA. Multiparous Holstein cows were randomly assigned to receive one of the four diets: control (n=11); whole flaxseed (WF, n=10), 60 and 80 g/kg (diet dry matter (DM) basis) of WF during the prepartum and postpartum periods, respectively; whole raw soybeans (WS, n=10), 120 and 160 g/kg (diet DM basis) of WS during the prepartum and postpartum periods, respectively; and calcium salts of unsaturated fatty acids (CSFA, n=11), 24 and 32 g/kg (diet DM basis) of CSFA during the prepartum and postpartum periods, respectively. Dry cows fed WF had higher DM and net energy of lactation (NEL) intake than those fed WS or CSFA. The FA supplementation did not alter DM and NDF apparent total tract digestibility, dry cows fed WF exhibited greater NDF total tract digestion than cows fed WS or CSFA. Feeding WS instead of CSFA did not alter NEL intake and total tract digestion of nutrients, but increased milk fat yield and concentration. Calculated efficiency of milk yield was not altered by diets. FA supplementation increased EB during the postpartum period. Experimental diets increased long-chain FA (saturated and unsaturated FA) in milk. In addition, cows fed WS and CSFA had higher C18:1 trans-11 FA and C18:2 cis, and lower C18:3 FA in milk than those fed WF. Furthermore, cows fed CSFA had higher C18:1 trans-11 and cis-9, trans-11 FA than cows fed WS. Although supplemental C18:2 and C18:3 FA did not influence the milk yield of cows, they positively affected EB and increased unsaturated long-chain FA in milk fat.

  17. True total-tract digestibility of phosphorus in corn and soybean meal for fifteen-kilogram pigs are additive in corn-soybean meal diet.

    PubMed

    Zhai, H; Adeola, O

    2013-01-01

    The objective of this study was to verify the additivity of true total-tract P digestibility (TPD) in corn and soybean meal (SBM) for 15-kg pigs. Fifty-four barrows with an average initial BW of 14.7±1.6 kg were used in a randomized complete block design with a 3×2 factorial arrangement of 6 diets. Three P sources included corn, SBM, and their mixture at a ratio of 2:1. Each P source was provided at low or high level. The diets were fed for a 5-d adjustment period followed by a total collection period of 7 d with ferric oxide as a marker to determine the initiation and termination of fecal collection. The results showed the high P level of each P source increased (P<0.001) P intake, fecal P output, and digested P compared with the low P level. The respective apparent total-tract digestibility of P were 35.66 and 40.57% for low and high P levels in corn, 35.72 and 38.04% for low and high P levels in SBM, and 41.85 and 38.53% for low and high P levels in the corn-soybean meal mixture without significant difference between P levels within P sources. Regressing daily digested P against daily P intake, the TPD was estimated at 40.53, 35.96, and 37.52% for corn, SBM, and their mixture, respectively. The expected TPD in corn and SBM mixture was calculated to be 37.92% based upon the P contribution coefficient calculated to be 0.428 for corn and 0.572 for SBM. The determined TPD (37.52%) in the mixture was not statistically different from the expected (37.92%). In conclusion, the TPD in corn and SBM are additive in corn-soybean meal diet for pigs.

  18. Effects of source and level of dietary neutral detergent fiber on feed intake, ruminal fermentation, ruminal digestion in situ, and total tract digestion in beef cattle fed pelleted concentrates with or without supplemental roughage.

    PubMed

    Marshall, S A; Campbell, C P; Mandell, I B; Wilton, J W

    1992-03-01

    The effects of source and level of dietary NDF on intake, ruminal digestion in situ, ruminal fermentation, and total tract digestion were evaluated in Hereford steers using a replicated 5 x 5 Latin square design. Diets contained 62 to 64% TDN and included 1) 80% control concentrate (contained pelleted ground grains) and 20% timothy hay (traditional diet), 2) 80% control concentrate and 20% alfalfa cubes, 3) 90% control concentrate and 10% cubes, 4) a completely pelleted diet using corn cobs as the primary NDF source, and 5) 80% textured (rolled instead of ground grains) concentrate and 20% hay. Dry matter intake differed (P less than .05) between the traditional and cube diets due to limited acceptance of alfalfa cubes. Increased (P less than .05) ruminal osmolality, total VFA, and NH3 N and lower (P less than .01) ruminal pH in steers fed corn cob and cube diets relative to steers fed the traditional diet were due to preferential consumption of concentrate over supplemental roughage and the resultant rapid fermentation of concentrates. Potentially degradable DM in the traditional diet exceeded (P less than .06) all other diets, resulting in the increased (P less than .10) extent of DM disappearance despite a slower (P less than .05) rate of DM disappearance. Rate of NDF disappearance and all in situ starch disappearance parameters were similar between the traditional, corn cob, and cube diets. All ruminal digestion parameters involving NDF disappearance were similar between hay diets and between cube diets, whereas rate and extent of starch disappearance differed (P less than .05) between hay diets. Although formulation of diets with different sources of dietary NDF did not affect total tract digestion of nutrients, nutrient availability and ruminal fermentation were altered due to dietary differences in sources of dietary NDF and preferential selection of feedstuffs by steers. PMID:1314254

  19. Early development of the digestive tract (pharynx and gut) in the embryos and pre-larvae of the European sea bass Dicentrarchus labrax.

    PubMed

    Sucré, E; Charmantier-Daures, M; Grousset, E; Charmantier, G; Cucchi-Mouillot, P

    2009-10-01

    The European sea bass Dicentrarchus labrax is a marine teleost important in Mediterranean aquaculture. The development of the entire digestive tract of D. labrax, including the pharynx, was investigated from early embryonic development to day 5 post hatching (dph), when the mouth opens. The digestive tract is initialized at stage 12 somites independently from two distinct infoldings of the endodermal sheet. In the pharyngeal region, the anterior infolding forms the pharynx and the first gill slits at stage 25 somites. The other three gill arches and slits are formed between 1 and 5 dph. Posteriorly, in the gut tube region, a posterior infolding forms the foregut, midgut and hindgut. The anus opens before hatching, at stage 28 somites. Associated organs (liver, pancreas and gall bladder) are all discernable from 3 dph. Some aspects of the development of the two independent initial infoldings seem original compared with data in the literature. These results are discussed and compared with embryonic and post-embryonic development patterns in other teleosts.

  20. AeroSpace Days 2013

    NASA Video Gallery

    At the eighth annual AeroSpace Days, first mom in space, Astronaut AnnaFisher, and Sen. Louise Lucas, interacted with students from Mack BennJr. Elementary School in Suffolk, Va. through NASA’s...

  1. Feeding distillers dried grains in replacement of forage in limit-fed dairy heifer rations: Effects on growth performance, rumen fermentation, and total-tract digestibility of nutrients.

    PubMed

    Manthey, A K; Anderson, J L; Perry, G A

    2016-09-01

    The objective of this study was to determine the effects of increasing dietary concentration of distillers dried grains (DDGS) in dairy heifer rations. A 16-wk randomized complete block design study was conducted using 48 Holstein heifers [199±2 d of age; body weight (BW) 206±2kg] to evaluate effects of dietary treatment on dry matter (DM) intake, average daily gain, growth performance, rumen fermentation, and nutrient digestibility. Treatments were (1) 30% DDGS with the diet fed at 2.65% of BW, (2) 40% DDGS with the diet fed at 2.50% of BW, and (3) 50% DDGS with the diet fed at 2.35% of BW. The remainder of the diet consisted of grass hay and 1.5% mineral mix. Heifers were individually limit-fed using Calan gates. Heifers were weighed every 2 wk and the ration amount offered was adjusted accordingly. Frame measurements and body condition score were recorded every 2wk. Rumen fluid was collected via esophageal tubing during wk 12 and 16 for pH, ammonia N, and volatile fatty acid analysis. Total-tract digestibility of nutrients was evaluated during wk 16 using fecal grab sampling. No treatment by week interactions were found for any of the growth parameters measured, and growth parameters did not differ among treatments. Heifer DM intake linearly decreased with increasing concentrations of DDGS. Body weight and average daily gain were similar among treatments, whereas gain:feed linearly increased across treatments, with a tendency for a treatment by time interaction. As the dietary concentrations of DDGS increased, rumen ammonia N linearly increased. Acetate proportion and acetate:propionate linearly decreased as DDGS increased, whereas propionate linearly increased. There were treatment by time interactions for propionate proportion and acetate:propionate. Increasing dietary concentrations of DDGS linearly increased total-tract digestibility of DM, organic matter, and crude protein. Limit-feeding diets with greater concentrations of DDGS improved gain:feed and

  2. Feeding distillers dried grains in replacement of forage in limit-fed dairy heifer rations: Effects on growth performance, rumen fermentation, and total-tract digestibility of nutrients.

    PubMed

    Manthey, A K; Anderson, J L; Perry, G A

    2016-09-01

    The objective of this study was to determine the effects of increasing dietary concentration of distillers dried grains (DDGS) in dairy heifer rations. A 16-wk randomized complete block design study was conducted using 48 Holstein heifers [199±2 d of age; body weight (BW) 206±2kg] to evaluate effects of dietary treatment on dry matter (DM) intake, average daily gain, growth performance, rumen fermentation, and nutrient digestibility. Treatments were (1) 30% DDGS with the diet fed at 2.65% of BW, (2) 40% DDGS with the diet fed at 2.50% of BW, and (3) 50% DDGS with the diet fed at 2.35% of BW. The remainder of the diet consisted of grass hay and 1.5% mineral mix. Heifers were individually limit-fed using Calan gates. Heifers were weighed every 2 wk and the ration amount offered was adjusted accordingly. Frame measurements and body condition score were recorded every 2wk. Rumen fluid was collected via esophageal tubing during wk 12 and 16 for pH, ammonia N, and volatile fatty acid analysis. Total-tract digestibility of nutrients was evaluated during wk 16 using fecal grab sampling. No treatment by week interactions were found for any of the growth parameters measured, and growth parameters did not differ among treatments. Heifer DM intake linearly decreased with increasing concentrations of DDGS. Body weight and average daily gain were similar among treatments, whereas gain:feed linearly increased across treatments, with a tendency for a treatment by time interaction. As the dietary concentrations of DDGS increased, rumen ammonia N linearly increased. Acetate proportion and acetate:propionate linearly decreased as DDGS increased, whereas propionate linearly increased. There were treatment by time interactions for propionate proportion and acetate:propionate. Increasing dietary concentrations of DDGS linearly increased total-tract digestibility of DM, organic matter, and crude protein. Limit-feeding diets with greater concentrations of DDGS improved gain:feed and

  3. The β-Defensin Gallinacin-6 Is Expressed in the Chicken Digestive Tract and Has Antimicrobial Activity against Food-Borne Pathogens▿

    PubMed Central

    van Dijk, Albert; Veldhuizen, Edwin J. A.; Kalkhove, Stefanie I. C.; Tjeerdsma-van Bokhoven, Johanna L. M.; Romijn, Roland A.; Haagsman, Henk P.

    2007-01-01

    Food-borne pathogens are responsible for most cases of food poisoning in developed countries and are often associated with poultry products, including chicken. Little is known about the role of β-defensins in the chicken digestive tract and their efficacy. In this study, the expression of chicken β-defensin gallinacin-6 (Gal-6) and its antimicrobial activity against food-borne pathogens were investigated. Reverse transcription-PCR analysis showed high expression of Gal-6 mRNA in the esophagus and crop, moderate expression in the glandular stomach, and low expression throughout the intestinal tract. Putative transcription factor binding sites for nuclear factor kappa beta, activator protein 1, and nuclear factor interleukin-6 were found in the Gal-6 gene upstream region, which suggests a possible inducible nature of the Gal-6 gene. In colony-counting assays, strong bactericidal and fungicidal activity was observed, including bactericidal activity against food-borne pathogens Campylobacter jejuni, Salmonella enterica serovar Typhimurium, Clostridium perfringens, and Escherichia coli. Treatment with 16 μg/ml synthetic Gal-6 resulted in a 3 log unit reduction in Clostridium perfringens survival within 60 min, indicating fast killing kinetics. Transmission electron microscopy examination of synthetic-Gal-6-treated Clostridium perfringens cells showed dose-dependent changes in morphology after 30 min, including intracellular granulation, cytoplasm retraction, irregular septum formation in dividing cells, and cell lysis. The high expression in the proximal digestive tract and broad antimicrobial activity suggest that chicken β-defensin gallinacin-6 plays an important role in chicken innate host defense. PMID:17194828

  4. The beta-defensin gallinacin-6 is expressed in the chicken digestive tract and has antimicrobial activity against food-borne pathogens.

    PubMed

    van Dijk, Albert; Veldhuizen, Edwin J A; Kalkhove, Stefanie I C; Tjeerdsma-van Bokhoven, Johanna L M; Romijn, Roland A; Haagsman, Henk P

    2007-03-01

    Food-borne pathogens are responsible for most cases of food poisoning in developed countries and are often associated with poultry products, including chicken. Little is known about the role of beta-defensins in the chicken digestive tract and their efficacy. In this study, the expression of chicken beta-defensin gallinacin-6 (Gal-6) and its antimicrobial activity against food-borne pathogens were investigated. Reverse transcription-PCR analysis showed high expression of Gal-6 mRNA in the esophagus and crop, moderate expression in the glandular stomach, and low expression throughout the intestinal tract. Putative transcription factor binding sites for nuclear factor kappa beta, activator protein 1, and nuclear factor interleukin-6 were found in the Gal-6 gene upstream region, which suggests a possible inducible nature of the Gal-6 gene. In colony-counting assays, strong bactericidal and fungicidal activity was observed, including bactericidal activity against food-borne pathogens Campylobacter jejuni, Salmonella enterica serovar Typhimurium, Clostridium perfringens, and Escherichia coli. Treatment with 16 mug/ml synthetic Gal-6 resulted in a 3 log unit reduction in Clostridium perfringens survival within 60 min, indicating fast killing kinetics. Transmission electron microscopy examination of synthetic-Gal-6-treated Clostridium perfringens cells showed dose-dependent changes in morphology after 30 min, including intracellular granulation, cytoplasm retraction, irregular septum formation in dividing cells, and cell lysis. The high expression in the proximal digestive tract and broad antimicrobial activity suggest that chicken beta-defensin gallinacin-6 plays an important role in chicken innate host defense. PMID:17194828

  5. Influence of whole wheat inclusion and a blend of essential oils on the performance, nutrient utilisation, digestive tract development and ileal microbiota profile of broiler chickens.

    PubMed

    Amerah, A M; Péron, A; Zaefarian, F; Ravindran, V

    2011-02-01

    1. The aim of the present experiment was to examine the influence of whole wheat inclusion and a blend of essential oils (EO; cinnamaldehyde and thymol) supplementation on the performance, nutrient utilisation, digestive tract development and ileal microbiota profile of broiler chickens. 2. The experimental design was a 2 × 2 factorial arrangement of treatments evaluating two wheat forms (ground wheat [GW] and whole wheat [WW]; 100 and 200 g/kg WW replacing GW during starter [1 to 21 d] and finisher [22 to 35 d] diets respectively) and two levels of EO inclusion (0 or 100 g/tonne diet). All dietary treatments were supplemented with 2000 xylanase units/kg feed. Broiler starter and finisher diets based on wheat and soybean meal were formulated and each diet fed ad libitum to 6 pens of 8 male broilers. 3. During the trial period (1-35 d), wheat form had no significant effect on weight gain or feed intake. However, WW inclusion tended (P = 0.06) to improve feed per gain. Essential oil supplementation significantly improved weight gain in both diets, but the improvements were greater in the GW diet as indicated by a significant wheat form × EO interaction. 4. Main effects of wheat form and EO on the relative weight, length and digesta content of various segments of the digestive tract were not significant. Significant interactions, however, were found for relative gizzard and caecal weights. Essential oil supplementation significantly increased the relative gizzard weight and lowered relative caecal weight in birds fed on the GW based diet, but had no effect in those fed on the WW based diet. 5. Whole wheat inclusion and EO supplementation significantly improved apparent ileal nitrogen digestibility. Apparent ileal digestible energy was not significantly influenced by the dietary treatments. 6. Ileal microbiota profiling, using denaturing gradient gel electrophoresis, showed that the ileal microbiota composition was influenced by feed form. The mean numbers of

  6. Effects of temperature, pH and NaCl on protease activity in digestive tract of young turbot, Scophthalmus maximus

    NASA Astrophysics Data System (ADS)

    Chen, Muyan; Zhang, Xiumei; Gao, Tianxiang; Chen, Chao

    2006-09-01

    The protease activity in digestive tract of young turbot Scophthalmus maximum was studied, and the optimal pH, temperature and NaCl concentration were determined for different portions of the fish's internal organs. The optimal activity in the fish's stomach was at pH of 2.2, while that in the intestinal extracts was within the alkaline range from 9.5 to 10.0. In hepatopancreas, the optimal pH was in low alkalinity at 8.5. The optimal reaction temperature was above 40°C in stomach, intestine and hepatopancreas. With increasing temperature, the pH value increased in stomach, while in the intestine, an opposite tendency was observed due to combined effect of pH and temperature. NaCl concentration showed inhibitory impact on protein digestion in hepatopancreas. The main protease for protein digestion in turbot seemed to be pepsin. Moreover, the maximum protease activity in different segments of intestine existed in the hindgut.

  7. Equine pre-caecal and total tract digestibility of individual carbohydrate fractions and their effect on caecal pH response.

    PubMed

    Brøkner, Christine; Austbø, Dag; Næsset, Jon Anders; Knudsen, Knud Erik Bach; Tauson, Anne-Helene

    2012-12-01

    The working hypothesis was that a minor postprandial caecal pH decline would affect apparent total tract digestibility (ATTD) of the fibre fraction in horses and, hence, that soluble fibre would amplify fermentation and consequently increase ATTD of fibre. This study was a 4 × 4 Latin Square design with a sequence of 17 days adaptation to the ration followed by 8 sampling days. The feed rations consisted of only timothy hay (Group H), hay plus molassed sugar beet pulp combined with either whole oats (Group OB) or barley (Group BB) and hay plus loose chaff based concentrate (Group M). Four horses fitted with permanent caecal cannulas and collection harnesses were used. A pH electrode with logger was inserted through the cannula and caecal pH was recorded at 1 min intervals for 8 h. The mobile nylon bag technique was used to quantify pre-caecal loss (PCL) of individual feedstuffs. Fibre was analysed as dietary fibre (DF), non-starch polysaccharides, soluble non-cellulosic polysaccharides (S-NCP), insoluble non-cellulosic polysaccharide (I-NCP) and neutral detergent fibre. The ATTD of the S-NCP fraction was above 0.8, which was 60% higher than for the I-NCP fraction. The PCL of starch were 0.98 (oats) and 0.75 (barley). The BB diet lowered (p < 0.001) postprandial caecal pH more than the other diets and a significant correlation was found between the lowest pH and ATTD of I-NCP (r = -0.66; p = 0.005). In conclusion, this study successfully measured the in vivo digestibility of individual fibre fractions and found that S-NCP was more digestible than the I-NCP, and that a single meal of unprocessed barley was sufficient to decrease caecal pH to such an extent that the fibre digestibility of the whole diet was negatively affected.

  8. True and standardized total tract phosphorus digestibility in canola meals from Brassica napus black and Brassica juncea yellow fed to growing pigs.

    PubMed

    Adhikari, P A; Heo, J M; Nyachoti, C M

    2015-01-01

    The aim was to determine the true total tract digestibility (TTTD) and standardized total tract digestibility (STTD) of P in canola meals from Brassica napus black (BNB) and Brassica juncea yellow (BJY) fed to growing pigs. Fifty-four barrows with an initial BW of 19.9 ± 0.22 kg (mean ± SEM) were allocated in 3 consecutive blocks to 1 of 9 dietary treatments in a randomized complete block design to give 6 replicate pigs per diet. Dietary treatments were cornstarch based with increasing concentrations of P, that is, 0.8, 1.6, 2.4, and 3.3 g/kg (as-fed basis) from either BNB or BJY as the sole source of P and a gelatin-based P-free diet. Limestone was added to maintain a Ca:total P ratio of 1.2:1 in all diets. All diets contained titanium dioxide (3 g/kg) as an indigestible marker. Daily feed allowance was calculated to supply 2.6 times the maintenance energy requirement based on the BW at the beginning of each period and offered in 2 equal portions at 0800 and 1600 h as a dry mash. Pigs were individually housed in metabolism crates and fed experimental diets for 16 d, including 9 d for adaptation to feed and 5 d for total but separate collection of feces and urine. The apparent total tract digestibility values of P increased from 19.0 to 30.0% for BNB and from 17.3 to 28.3% for BJY as the dietary P content increased from 0.8 to 3.3 g/kg DM. The TTTD of P was determined using the regression analysis as dietary P content increased from 0.8 to 3.3 g/kg whereas the STTD of P was calculated for the diet with the highest P content (i.e., 3.3 g/kg, as-fed basis) using the P-free diet to estimate endogenous P losses (EPL). The total and basal EPL estimates obtained with regression analysis and the P-free diet were 665 ± 0.03 and 209 ± 96 mg/kg DMI, respectively. The TTTD of P was 33.3 and 32.0% in BNB and BJY, respectively. Respective STTD values were 31.0 and 28.3%. The results indicated that the TTTD and STTD of P were comparable in the 2 canola meals from BNB and BJY

  9. The influence of dietary fibre source and level on the development of the gastrointestinal tract, digestibility and energy metabolism in broiler chickens.

    PubMed

    Jørgensen, H; Zhao, X Q; Knudsen, K E; Eggum, B O

    1996-03-01

    The present study was undertaken to provide detailed information about the effect of fibre source (pea fibre, wheat bran or oat bran) at inclusion levels of 0, 187 and 375 g/kg diet on the development of the digestive tract, nutrient digestibility and energy and protein metabolism in broiler chickens. Heat production was measured using open-air-circuit respiration chambers. Diets with increasing levels of pea fibre decreased the DM in droppings and increased excreta output (2.5-fold) relative to DM intake. Adaptation to increased dietary fibre levels included increases in the size of the digestive system, with pea fibre exerting a stronger impact than wheat bran or oat bran. The length of the intestine, and particularly the length and weight of the caecum, increased with the fibre level. The digestibility of all nutrients also decreased with increasing fibre level. The decrease in the digestibility in relation to NSP for the three fibre sources was bigger for oat bran (0.0020 per g dietary NSP) than for pea fibre and wheat bran (0.0014 and 0.0016 per g dietary NSP) indicating that the cell walls in oat bran (aleurone and subaleurone) had a significant negative effect on the digestibility of cellular nutrients, i.e. protein and fat. The degradation of the NSP constituents was far lower in chickens than found in other animal species such as pigs and rats, thus supporting the view that chickens do not ferment fibre polymers to a great extent. Excretion of organic acids (mainly lactic acid and acetic acid) accounted for up to 2% of metabolizable energy (ME) intake with the highest excretion for the high-fibre diets. H2 excretion was related to the amount of NSP degraded and indicated higher microbial fermentation with increasing fibre levels. The chickens' feed intake responded to a great extent to dietary ME concentration but expressed in terms of metabolic body size (W0.75) ME intake was depressed at the high fibre levels. Dietary NSP was able to explain between 86

  10. Influence of conditioning temperature on the performance, nutrient utilisation and digestive tract development of broilers fed on maize- and wheat-based diets.

    PubMed

    Abdollahi, M R; Ravindran, V; Wester, T J; Ravindran, G; Thomas, D V

    2010-10-01

    1. The influence of conditioning temperature on the performance, nutrient utilisation and digestive tract development of broilers fed on maize- and wheat-based diets was examined up to 21 d of age. The experimental design was a 2 × 3 factorial arrangement of treatments evaluating two grain types (maize and wheat) and three conditioning temperatures (60°C, 75°C and 90°C). Broiler starter diets, each based on one grain (maize or wheat), were formulated and pelleted at the three temperatures. 2. Increasing conditioning temperature decreased the body-weight gain and feed intake in wheat-based diets, but birds fed on maize-based diets conditioned at 60°C and 90°C had higher body-weight gain and feed intake than those fed on the diet conditioned at 75°C. Increasing conditioning temperature increased feed per body-weight gain in both grain-type diets but improved pellet durability index (PDI) only in wheat-based diets; PDI was unaffected in maize-based diets. 3. In wheat-based diets, increasing conditioning temperature decreased the ileal digestibility of nitrogen and starch. Ileal nitrogen digestibility of maize-based diets conditioned at 60°C and 90°C was higher than at 75°C. Starch digestibility was unaffected by conditioning temperature in maize-based diets. No effect of conditioning temperature was found for apparent metabolisable energy (AME). Increasing conditioning temperature decreased digestible protein and AME intakes in wheat-based diets but, in maize-based diets, birds fed on the diet conditioned at 75°C had lower digestible protein and AME intakes compared to those fed on diets conditioned at 60°C and 90°C. 4. Small intestine was longer in birds fed on diets conditioned at 75°C and 90°C compared with those fed on diets conditioned at 60°C. 5. Overall, the data suggest that while the effects of conditioning temperature on body-weight gain and feed intake of broilers to 21 d of age differed depending on the grain type, feed per body-weight gain

  11. Total tract nutrient digestion and milk fatty acid profile of dairy cows fed diets containing different levels of whole raw soya beans.

    PubMed

    Venturelli, B C; de Freitas Júnior, J E; Takiya, C S; de Araújo, A P C; Santos, M C B; Calomeni, G D; Gardinal, R; Vendramini, T H A; Rennó, F P

    2015-12-01

    Whole oilseeds such as soya beans have been utilized in dairy rations to supply additional fat and protein. However, antinutritional components contained in soya beans, such as trypsin inhibitors and haemagglutinins (lectins) may alter digestibility of nutrients and consequently affect animal performance. The objective of the present experiment was to quantify the effect of different levels of whole raw soya beans in diets of dairy cows on nutrient intake, total tract digestion, nutrient balances and milk yield and composition. Sixteen mid to late-lactation cows (228 ± 20 days in milk; mean ± SD) were used in four replicated 4 × 4 Latin square design experiment with 21-d periods. Cows were assigned to each square according to milk yield and DIM. The animals were randomly allocated to treatments: control (without soya beans addition; CO), WS9, WS18 and WS27, with addition of 9%, 18% and 27% of whole raw soya bean in diet on a dry matter (DM) basis respectively. All diets contained identical forage and concentrate components and consisted of maize silage and concentrate based on ground corn and soya beans at a ratio of 60:40. There were no differences in OM, CP, NDF and NEL intakes (kg/day and MJ/day) among the treatments (p > 0.05). However, DM and NFC intakes were negatively affected (p = 0.04 and p < 0.01, respectively) and ether extract (EE) intake was positively affected (p < 0.01). Total tract digestion increased linearly with whole raw soya beans for EE (p < 0.01) and NDF (p = 0.01). The excretion (kg/day) of digested soya beans grains increased linearly according to addition of whole raw soya beans. However, the nutritive characteristics of excreted grains were not altered. Milk (kg), milk lactose (kg) and protein (kg) yield decreased linearly (p < 0.01, p < 0.01 and p = 0.04, respectively) milk fat content (%) increased linearly (p < 0.01) with whole raw soya beans inclusion. Increasing addition of whole raw soya beans affected milk fatty acid profile

  12. Influence of low protein diets on gene expression of digestive enzymes and hormone secretion in the gastrointestinal tract of young weaned piglets*

    PubMed Central

    Tian, Zhi-mei; Ma, Xian-yong; Yang, Xue-fen; Fan, Qiu-li; Xiong, Yun-xia; Qiu, Yue-qin; Wang, Li; Wen, Xiao-lu; Jiang, Zong-yong

    2016-01-01

    To investigate dietary protein level effects on digestive mechanisms, weaned piglets were fed for 45 d with diets containing 20%, 17%, or 14% crude protein (CP) supplemented to meet requirements for essential amino acids. This article describes the influence of dietary protein on gastrointestinal hormones and expression of an array of digestive enzymes in the gastrointestinal tract and pancreas. Results indicated that there were no significant differences in expression of enzymes involved in carbohydrate digestion, except for maltase in the duodenum. In the jejunum, amylase expression in pigs fed 20% CP was much higher than that in pigs fed other diets (P<0.05) and maltase expression in those fed 17% CP was higher than that in other treatments (P<0.05). Although there were no remarkable differences in expression of aminopeptidase in the small intestine or carboxypeptidase in the pancreas (P>0.05), there was a trend towards higher expression of various proteases in pigs fed 17% CP. The duodenal expression of enteropeptidase in diets with 14% and 17% CP was significantly higher than that with 20% CP (P<0.05), but treatment differences did not existed in jejunum (P>0.05). The expression of GPR93 as a nutrient-responsive G protein-coupled receptor in 14% and 17% CP diets was significantly higher than that in 20% CP diet in the small intestine (P<0.05). The expressions of genes for pancreatic enzymes, lipase and elastase, were significantly higher in pigs fed diets with low CP, while similar trends occurred for carboxypeptidase, chymotrypsin and amylase. Conversely, the gastric expressions of pepsinogen A and progastricsin were lower with the 17% CP diet. Differences between treatments were found in the gastric antral contents of cholecystokinin and somatostatin: both increased in pigs fed 17% CP, accompanied by decreased content of motilin, which was also seen in plasma concentrations. These patterns were not reflected in duodenal contents. In general, 17% dietary CP

  13. Total tract nutrient digestion and milk fatty acid profile of dairy cows fed diets containing different levels of whole raw soya beans.

    PubMed

    Venturelli, B C; de Freitas Júnior, J E; Takiya, C S; de Araújo, A P C; Santos, M C B; Calomeni, G D; Gardinal, R; Vendramini, T H A; Rennó, F P

    2015-12-01

    Whole oilseeds such as soya beans have been utilized in dairy rations to supply additional fat and protein. However, antinutritional components contained in soya beans, such as trypsin inhibitors and haemagglutinins (lectins) may alter digestibility of nutrients and consequently affect animal performance. The objective of the present experiment was to quantify the effect of different levels of whole raw soya beans in diets of dairy cows on nutrient intake, total tract digestion, nutrient balances and milk yield and composition. Sixteen mid to late-lactation cows (228 ± 20 days in milk; mean ± SD) were used in four replicated 4 × 4 Latin square design experiment with 21-d periods. Cows were assigned to each square according to milk yield and DIM. The animals were randomly allocated to treatments: control (without soya beans addition; CO), WS9, WS18 and WS27, with addition of 9%, 18% and 27% of whole raw soya bean in diet on a dry matter (DM) basis respectively. All diets contained identical forage and concentrate components and consisted of maize silage and concentrate based on ground corn and soya beans at a ratio of 60:40. There were no differences in OM, CP, NDF and NEL intakes (kg/day and MJ/day) among the treatments (p > 0.05). However, DM and NFC intakes were negatively affected (p = 0.04 and p < 0.01, respectively) and ether extract (EE) intake was positively affected (p < 0.01). Total tract digestion increased linearly with whole raw soya beans for EE (p < 0.01) and NDF (p = 0.01). The excretion (kg/day) of digested soya beans grains increased linearly according to addition of whole raw soya beans. However, the nutritive characteristics of excreted grains were not altered. Milk (kg), milk lactose (kg) and protein (kg) yield decreased linearly (p < 0.01, p < 0.01 and p = 0.04, respectively) milk fat content (%) increased linearly (p < 0.01) with whole raw soya beans inclusion. Increasing addition of whole raw soya beans affected milk fatty acid profile

  14. Hypersonic Interplanetary Flight: Aero Gravity Assist

    NASA Technical Reports Server (NTRS)

    Bowers, Al; Banks, Dan; Randolph, Jim

    2006-01-01

    The use of aero-gravity assist during hypersonic interplanetary flights is highlighted. Specifically, the use of large versus small planet for gravity asssist maneuvers, aero-gravity assist trajectories, launch opportunities and planetary waverider performance are addressed.

  15. AeroDyn Theory Manual

    SciTech Connect

    Moriarty, P. J.; Hansen, A. C.

    2005-01-01

    AeroDyn is a set of routines used in conjunction with an aeroelastic simulation code to predict the aerodynamics of horizontal axis wind turbines. These subroutines provide several different models whose theoretical bases are described in this manual. AeroDyn contains two models for calculating the effect of wind turbine wakes: the blade element momentum theory and the generalized dynamic-wake theory. Blade element momentum theory is the classical standard used by many wind turbine designers and generalized dynamic wake theory is a more recent model useful for modeling skewed and unsteady wake dynamics. When using the blade element momentum theory, various corrections are available for the user, such as incorporating the aerodynamic effects of tip losses, hub losses, and skewed wakes. With the generalized dynamic wake, all of these effects are automatically included. Both of these methods are used to calculate the axial induced velocities from the wake in the rotor plane. The user also has the option of calculating the rotational induced velocity. In addition, AeroDyn contains an important model for dynamic stall based on the semi-empirical Beddoes-Leishman model. This model is particularly important for yawed wind turbines. Another aerodynamic model in AeroDyn is a tower shadow model based on potential flow around a cylinder and an expanding wake. Finally, AeroDyn has the ability to read several different formats of wind input, including single-point hub-height wind files or multiple-point turbulent winds.

  16. Acylated oleanane-type triterpene saponins from the flowers of Bellis perennis show anti-proliferative activities against human digestive tract carcinoma cell lines.

    PubMed

    Ninomiya, Kiyofumi; Motai, Chiaki; Nishida, Eriko; Kitagawa, Niichiro; Yoshihara, Kazuya; Hayakawa, Takao; Muraoka, Osamu; Li, Xuezheng; Nakamura, Seikou; Yoshikawa, Masayuki; Matsuda, Hisashi; Morikawa, Toshio

    2016-07-01

    Seven oleanane-type triterpene saponin bisdesmosides, perennisaponins N-T (1-7), were newly isolated from a methanol extract of daisy, the flowers of Bellis perennis L. (Asteraceae). The structures were determined based on chemical and physicochemical data and confirmed using previously isolated related compounds as references. The isolates, including 13 previously reported perennisaponins A-M (8-20), exhibited anti-proliferative activities against human digestive tract carcinoma HSC-2, HSC-4, and MKN-45 cells. Among them, perennisaponin O (2, IC50 = 11.2, 14.3, and 6.9 μM, respectively) showed relatively strong activities. The mechanism of action of 2 against HSC-2 was found to involve apoptotic cell death. PMID:27178360

  17. Interactive effects of bulk density of steam-flaked corn and concentration of Sweet Bran on feedlot cattle performance, carcass characteristics, and apparent total tract nutrient digestibility.

    PubMed

    Domby, E M; Anele, U Y; Gautam, K K; Hergenreder, J E; Pepper-Yowell, A R; Galyean, M L

    2014-03-01

    Two hundred twenty-four steers (initial BW = 363 ± 1.57 kg) were used in a 2 × 3 + 1 factorial arrangement of treatments to evaluate the interactive effects of concentration of wet corn gluten feed (WCGF) and bulk density (BD) of steam-flaked corn (SFC) on feedlot performance, carcass characteristics, and apparent total tract digestibility. Diets consisted of 0, 15, or 30% WCGF (DM basis) with a BD of SFC at 283 or 360 g/L. The additional treatment consisted of 15% WCGF, SFC at 283 g/L, and a 6% inclusion of alfalfa hay vs. 9% for all other treatments. Steers were fed once daily for an average of 163 d. During a 5-d digestion period, DMI was measured, and fecal samples were collected for measurement of nutrient digestibility using dietary acid insoluble ash as a marker. There were few WCGF × BD interactions for feedlot performance, carcass characteristics, and digestibility. Similarly, contrasts between the treatment containing 15% WCGF/360 g/L SFC and 15% WCGF/360 g/L with 6% hay yielded few differences for performance and carcass data. Final BW responded quadratically (P ≤ 0.02) to WCGF inclusion and showed increased (P ≤ 0.007) BW for greater BD. As WCGF inclusion increased, G:F and calculated NE values (P ≤ 0.03) decreased quadratically. Steers consuming 360 g/L SFC had greater (P < 0.05) G:F than those fed 283 g/L SFC. Marbling score, HCW, 12th-rib fat thickness, and calculated yield grade increased quadratically (P ≤ 0.04) with increased inclusion of WCGF. Percentage of cattle grading premium Choice or greater responded quadratically (P = 0.04) to WCGF concentration. Increasing BD increased (P ≤ 0.01) HCW, dressing percent, marbling score, and 12th-rib fat thickness and decreased calculated yield grade and percentage of cattle grading Select; however, lower BD tended (P = 0.09) to increase LM area. Intake of DM, OM, CP, and NDF and fecal output during the digestibility period increased linearly (P ≤ 0.01) with increasing WCGF, and greater BD

  18. [Effects of afferent vagal stimulation and distention of the upper digestive tract on the micturition reflex and activity of the pontine micturition center in dogs].

    PubMed

    Moda, Y

    1992-12-01

    (1) The study was performed to elucidate the effects of afferent vagal stimulation and distension of the digestive tract on the micturition reflex in 21 acute decerebrate dogs immobilized with gallamine. Electrical stimulation of the central cut end of the cervical vagus nerve with high voltage (17.5-25 V) and moderate frequency (10-50 Hz) elicited in most cases inhibition of the periodic bladder contractions and of outflows of the pelvic vesical branch which were induced by a sustained intravesical pressure of 10-15 cmH2O. Distension of the thoracic esophagus, the stomach, and the duodenum also induced inhibition of the bladder contractions and of the pelvic outflow to the bladder. Such inhibitions were abolished after bilateral cervical vagotomies except a few cases of distension of the duodenum. (2) Another series of experiments were undertaken to clear the effect of afferent vagal stimulation on the electrical activity of the pontine micturition center in 10 acute decerebrate dogs. By means of an extracellular glass microelectrode method, unitary discharges synchronized with the grouping discharges in the pelvic vesical branch with a rhythm of 2.2-2.5 Hz were recorded from the pontine micturition center in the dorsolateral pontine tegmentum. Such a type of discharges was detected in 6 of 59 units which discharged by afferent stimulation of the pelvic vesical branch. This type of discharges was inhibited by afferent vagal stimulation at the supradiaphragmatic level. From these results, it may be concluded that the afferent pathway of the bladder relaxation reflex induced by distension of the upper digestive tract is mainly involved in the vagal nerves, but in some cases of the strong distension of the duodenum, the pathway is in splanchnic nerves, and that inhibition of the bladder contraction after stimulation of vagal nerve is induced by suppression of the pontine micturition centers.

  19. Modes of transmission of Glugea plecoglossi (Microspora) via the skin and digestive tract in an experimental infection model using rainbow trout, Oncorhynchus mykiss (Walbaum).

    PubMed

    Lee, S-J; Yokoyama, H; Ogawa, K

    2004-08-01

    Glugea plecoglossi (Microspora) is a significant cause of economic loss in cultured ayu, Plecoglossus altivelis, in Japan, due to the unsightly appearance of infected fish harbouring xenomas in the body cavity. Modes of transmission of G. plecoglossi via the skin and digestive tract were studied in an experimental infection model using rainbow trout, Oncorhynchus mykiss. Combined with Uvitex 2B and in situ hybridization (ISH) assays, the early development of G. plecoglossi was successfully traced. Following a bath exposure of fish Uvitex 2B-labelled G. plecoglossi spores were observed to attach to microscopic injuries (trypan blue-positive sites) of fish skin, after which ISH-positive sporoplasms were found to invade the epidermis as early as 5 min post-infection (PI), migrating rapidly to the subdermis. It was also shown that G. plecoglossi entering via the skin does not spread into the internal organs but develops into subdermal xenomas. After rainbow trout were exposed to G. plecoglossi spores by oral intubation, spores germinated in the intestinal lumen, followed by penetration of sporoplasms into the gut mucosal epithelium 5 min PI. In vitro trials determining stimulation factors (fish mucus, changes in pH, digestive enzymes) for the extrusion of the polar tube were inconclusive. The present study indicates that skin wounds and the gut epithelium can be portals of entry of G. plecoglossi and that natural infection in fish seems to occur perorally rather than via the skin. PMID:15291785

  20. Evaluation of two milk replacers fed to hand-reared cheetah cubs (Acinonyx jubatus): nutrient composition, apparent total tract digestibility, and comparison to maternal cheetah milk.

    PubMed

    Bell, Katherine M; Rutherfurd, Shane M; Cottam, Yvette H; Hendriks, Wouter H

    2011-01-01

    Commercially prepared milk replacers are frequently used to provide the sole source of nutrition for hand-reared cheetah cubs (Acinonyx jubatus). The nutrient composition of two commonly used milk replacers was determined. Using titanium dioxide as an indigestible marker, nutrient digestibility was calculated from the analyses of fecal samples collected from each cub (n = 4 on formula 1, and n = 2 on formula 2). Mean apparent total tract digestibility for both formulas was >90% for all nutrients analyzed (crude protein, amino acids, crude fat (CF), and dry matter). However, the total CF content and the concentration of the essential fatty acids, such as α-linolenic, linolenic, and arachidonic acid, of both formulas was lower than reported for maternal cheetah milk. Additionally, one formula contained a comparatively high amount of carbohydrate, at the expense of protein. Although data were lacking for cheetah maternal milk, comparison with domestic cat milk revealed high concentrations of a number of minerals (K, Fe, Zn, and Cu), while vitamin D(3) was not detected in one formula. Both formulas were low in the majority of essential amino acids compared with domestic cat maternal milk. Despite their apparently high digestibility, neither formula was complete or balanced in terms of nutrient concentrations and ratios when maternal cheetah milk and/or the requirements established for growth in domestic cats were used as estimates of ideal. On this basis, although all cubs in this study were healthy and maintained good body conditions for the duration of the trial, the results of dietary analyses indicate that these milk replacers may not provide optimal nutrition for growth in cheetah cubs when used for extended periods.

  1. Comparison of values for standardized total tract digestibility and relative bioavailability of phosphorus in dicalcium phosphate and distillers dried grains with solubles fed to growing pigs.

    PubMed

    Baker, S R; Kim, B G; Stein, H H

    2013-01-01

    Two experiments were conducted to compare values for the standardized total tract digestibility (STTD) and the relative bioavailability of P in dicalcium phosphate (DCP) and distillers dried grains with solubles (DDGS) when fed to growing pigs. In Exp. 1, the apparent total tract digestibility (ATTD), the basal endogenous P loss (EPL), and the STTD of P in DCP and DDGS were determined. Eighteen pigs (initial BW: 34.93±1.04 kg) were allotted to 3 cornstarch-based diets in a randomized complete block design and housed individually in metabolism cages. Two diets contained DCP and DDGS, respectively, as the sole source of P and the last diet was a P-free diet that was used to measure EPL from the pigs. Results indicated that the ATTD of P in DCP and DDGS were 86.1 and 58.8%, respectively, and the STTD of P in DCP and DDGS were 93.1 and 63.1%, respectively. The EPL was determined at 174 mg/kg DMI. In Exp. 2, 42 pigs (initial BW: 29.02±2.03 kg) were allotted to 7 dietary treatments in a randomized complete block design. Pigs were housed individually and allowed ad libitum access to feed and water. A basal diet (0.22% P) based on corn, casein, cornstarch, and potato protein concentrate was formulated. Three additional diets were formulated by adding 0.04, 0.08, or 0.12% P from DCP to the basal diet to create diets containing 0.26, 0.30, or 0.34% P. The last 3 diets were formulated by adding 0.04, 0.08, or 0.12% P from DDGS to the basal diet at the expense of cornstarch. Pigs were fed experimental diets for 28 d. They were then euthanized and the third and fourth metacarpals from the right front foot were collected. Metacarpal bone ash and bone P were regressed against P intake for each ingredient and via slope ratio methodology, it was determined that the bioavailability of P in DDGS was 87% relative to that in DCP. It was concluded from this work that the value for relative bioavailability of P in DDGS overestimates the digestibility of P in DDGS and values for the

  2. Effects of production area and microbial phytase on the apparent and standardized total tract digestibility of phosphorus in soybean meal fed to growing pigs.

    PubMed

    Sotak-Peper, K M; González-Vega, J C; Stein, H H

    2016-06-01

    An experiment was conducted to determine if the area in which soybeans are grown influences the concentration of P, phytate, and macro- and microminerals in the soybean meal (SBM) produced from the beans and, therefore, also influences the apparent total tract digestibility (ATTD) and the standardized total tract digestibility (STTD) of P in SBM. The second objective was to test the hypothesis that inclusion of microbial phytase will increase the ATTD and STTD of P in SBM regardless of where the beans were grown. Twenty sources of SBM were procured from crushing facilities located in different regions of the United States that were separated into 3 zones: 1) the northern growing area (Michigan, Minnesota, and South Dakota), 2) the eastern growing area (Georgia, Illinois, Indiana, and Ohio), and 3) the western growing area (Iowa, Missouri, and Nebraska). For each source of SBM, 2 diets based on cornstarch and SBM were formulated; one of these diets contained no microbial phytase and the other diet contained 500 units/kg of microbial phytase. Two hundred growing barrows (16.90 ± 1.79 kg initial BW) were individually placed in metabolism crates and allotted to a randomized complete block design with 40 diets and 5 replicate pigs per treatment. Feces were collected for 4 d after a 4-d adaptation period using the marker-to-marker procedure. Results indicated that there were no differences in concentration of Ca, P, phytate, and macro- and microminerals among SBM from the different zones. However, there was a tendency ( = 0.055) for an increase in concentration of nonphytate P in SBM from the western growing area (0.25%) compared with SBM from the northern growing area (0.23%) and the eastern growing area (0.23%). There were no differences in feed intake, absorbed P, ATTD of P, STTD of P, Ca intake, Ca output, or ATTD of Ca for pigs fed SBM from the 3 zones. However, there was a tendency (P = 0.066) for an increase in P intake and P output from pigs fed SBM from the

  3. Interaction of molasses and monensin in alfalfa hay- or corn silage-based diets on rumen fermentation, total tract digestibility, and milk production by Holstein cows.

    PubMed

    Oelker, E R; Reveneau, C; Firkins, J L

    2009-01-01

    Sugar supplementation can stimulate rumen microbial growth and possibly fiber digestibility; however, excess ruminal carbohydrate availability relative to rumen-degradable protein (RDP) can promote energy spilling by microbes, decrease rumen pH, or depress fiber digestibility. Both RDP supply and rumen pH might be altered by forage source and monensin. Therefore, the objective of this study was to evaluate interactions of a sugar source (molasses) with monensin and 2 forage sources on rumen fermentation, total tract digestibility, and production and fatty acid composition of milk. Seven ruminally cannulated lactating Holstein cows were used in a 5 x 7 incomplete Latin square design with five 28-d periods. Four corn silage diets consisted of 1) control (C), 2) 2.6% molasses (M), 3) 2.6% molasses plus 0.45% urea (MU), or 4) 2.6% molasses plus 0.45% urea plus monensin sodium (Rumensin, at the intermediate dosage from the label, 16 g/909 kg of dry matter; MUR). Three chopped alfalfa hay diets consisted of 1) control (C), 2) 2.6% molasses (M), or 3) 2.6% molasses plus Rumensin (MR). Urea was added to corn silage diets to provide RDP comparable to alfalfa hay diets with no urea. Corn silage C and M diets were balanced to have 16.2% crude protein; and the remaining diets, 17.2% crude protein. Dry matter intake was not affected by treatment, but there was a trend for lower milk production in alfalfa hay diets compared with corn silage diets. Despite increased total volatile fatty acid and acetate concentrations in the rumen, total tract organic matter digestibility was lower for alfalfa hay-fed cows. Rumensin did not affect volatile fatty acid concentrations but decreased milk fat from 3.22 to 2.72% in corn silage diets but less in alfalfa hay diets. Medium-chain milk fatty acids (% of total fat) were lower for alfalfa hay compared with corn silage diets, and short-chain milk fatty acids tended to decrease when Rumensin was added. In whole rumen contents, concentrations of

  4. Gasterophilosis in horses in Sardinia (Italy): effect of meteorological variables on adult egg-laying activity and presence of larvae in the digestive tract, and update of species.

    PubMed

    Pilo, Cristian; Altea, Antonella; Scala, Antonio

    2015-05-01

    Gasterophilus larvae are common obligate parasites of the digestive tract of the equids. Horses become infected with this parasite by ingesting the larvae hatched from eggs laid by the female flies. In this study carried out monthly, we (i) counted the Gasterophilus eggs deposited by female flies on the coat of 30 grazing horses, (ii) counted and identified the Gasterophilus larvae retrieved from the digestive tract of 128 slaughtered horses, and (iii) compared these results to meteorological data. Eggs were deposited on all monitored horses, and were present from October to January and from May to September, whereas they were absent from February to April. The number of laid eggs was significantly different between the months, body regions, genders, and age classes (p < 0.05). Larvae were recovered in 112 (87.5%) horses, and 6 species of Gasterophilus were identified. The prevailing species were Gasterophilus intestinalis (recovered in 110 horses; 85.9%) and Gasterophilus nasalis (69 horses; 53.9 %), recovered in all months. Gasterophilus inermis (5 horses; 3.9%), Gasterophilus pecorum (3 horses; 2.3%), Gasterophilus haemorrhoidalis (3 horses; 2.3%)¸ and Gasterophilus meridionalis (2 horses; 1.6%) larvae were also found. Significant differences were found among monthly larval burdens for both Gasterophilus spp. and G. intestinalis (p < 0.05), but not for G. nasalis (p > 0.05). Larval burdens and prevalences did not differed significantly between both genders and age classes (p > 0.05). Monthly eggs and larvae trends were not significantly correlated (p > 0.05). With regard to the meteorological variables, minimum air temperature was significantly correlated with the eggs trend (rho = 1.000; p < 0.001) and maximum air temperature with the Gasterophilus spp. (rho = 0.972; p < 0.001) and G. intestinalis (rho = 0.972; p < 0.001) larvae trends. In addition, the number of hours with a temperature below +10 °C was

  5. The electrical activity of the digestive tract of the sheep as an indication of the mechanical events in various regions

    PubMed Central

    Ruckebusch, Y.

    1970-01-01

    1. A method is described in the conscious sheep for recording oscillographically the electrical potentials led from enamelled stainless-steel wires implanted in the wall of the stomach and intestine. 2. Slow waves characterized by cyclically recurring and rhythmic fluctuation in voltage have been recorded, together with the superimposed fast activity or burst of spikes when the muscle is contracting. The whole activity comprised a distinguishable pattern of grouped discharge which is synchronous with mechanical events within different regions of the alimentary tract. 3. Grouped discharge occurs at a regular frequency of 7/min in the pyloric part of the abomasum and 18/min from the intestine, but 13/min from the middle duodenum and proximal ileum. Only the major grouped discharges of the fore-stomach is correlated with the orderly sequential movements of the reticulum and rumen. 4. The relationship between electrical and mechanical activity of the reticulo-rumenal movements was examined at rest, and during feeding and ruminating. 5. Electrical correlates of motor activity in the small bowel were investigated under different dietary regimens. PMID:5501488

  6. Temporal and spatial expression of Muc2 and Muc5ac mucins during rat respiratory and digestive tracts development.

    PubMed

    Ferretti, V A; Segal-Eiras, A; Barbeito, C G; Croce, M V

    2016-02-01

    Secreted mucins constitute a crucial part of the gel that protects respiratory and digestive epithelia, being MUC2/Muc2 the predominant gel-forming mucin of the intestine while MUC5AC/Muc5ac is one of the gel-forming mucins most expressed at the airways. In this study, we have analyzed Muc2 and Muc5ac during rat development by using immunohistochemistry, Western blotting and RT-PCR. We demonstrated that rat Muc2 was expressed in fetal intestinal goblet cells of surface epithelium of villi and developing Lieberkühn crypts. In neonates and adults, Muc2 was expressed at luminal goblet cells of small and large intestine and at gastric mucous and glandular cells. Muc5ac protein was observed in embryonic gastric and lung samples; expression increased during development and postnatal and adult life. After birth, a low reaction was detected at the tracheal surface epithelium and glands, which increased in adults. PMID:26850552

  7. Effect of slow-release urea inclusion in diets containing modified corn distillers grains on total tract digestibility and ruminal fermentation in feedlot cattle.

    PubMed

    Ceconi, I; Ruiz-Moreno, M J; DiLorenzo, N; DiCostanzo, A; Crawford, G I

    2015-08-01

    Ruminal degradable intake protein (DIP) deficit may result when cattle are fed diets containing a greater inclusion of processed corn grain and small to moderate inclusion of corn distillers grains (DG). This deficit may arise from greater proportions of rapidly fermentable carbohydrates and RUP in corn grain. Urea-derived N is 100% DIP; however, rates of degradation of carbohydrates and conventional urea (CU) may not match. Therefore, beneficial effects may result from the use of slow-release urea (SRU) sources over CU when added to DIP-deficient diets. An experiment was conducted to evaluate the effect of increasing DIP concentration through inclusion of 1 of 2 SRU sources or CU in DG-containing feedlot diets on ruminal fermentation and total tract digestibility. In addition, an in situ experiment was conducted to characterize N disappearance of urea sources from polyester bags. Four ruminally cannulated steers (initial BW = 588 ± 8 kg) were arranged in a 4 × 4 Latin square design and assigned randomly to 1 of 4 dietary treatments containing 0% (CON) or 0.6% urea in the form of CU (UREA) or SRU as Optigen II (polymer-encapsulated urea; OPTI) or NitroShure (lipid-encapsulated urea; NITRO), and 30% corn earlage, 20% modified corn DG with solubles, 7.8% corn silage, 4.3% dry supplement, and dry-rolled corn (DM basis). Dietary DIP was estimated at 6.6% and 8.3% for CON and urea-containing dietary treatments, respectively. Steers were fed ad libitum once daily. Differences in purine derivatives-to-creatinine (PDC) index between treatments were used as indicators of differences in microbial CP synthesis. Intake of OM, digestibility of OM, NDF, CP, and starch, ruminal pH, total VFA ruminal concentration, and PDC index were not affected by treatment ( ≥ 0.21). Concentration of ammonia-N noticeably peaked at 4 h after feed delivery for cattle fed UREA (treatment × time, = 0.06) and measured at least 5.5 mg/dL for any treatment and at any hour after feed delivery

  8. Evaluation of the rabbit as a model for Chagas disease-II. Histopathologic studies of the heart, digestive tract and skeletal muscle.

    PubMed

    da Silva, A M; Eduardo Ramirez, L; Vargas, M; Chapadeiro, E; Brener, Z

    1996-01-01

    In order to investigate the value of the rabbit as an experimental model for Chagas' disease, seventy one animals were inoculated with different Trypanosoma cruzi strains and routes. The rabbits were submitted to necropsy in acute (earlier than three months of infection), recent chronic (three to six months) and late chronic (later than six months) phases. Myocarditis, generally focal and endomysial, occurred in 94.1%, 66.7% and 70.8% of the infected rabbits respectively in the acute, recent chronic and late chronic phases. The myocardial inflammatory exudate was composed by mononuclear cells, and also polymorphonuclear cells in the acute phase. In most cases of the late chronic phase, the myocarditis was similar to that described in the indeterminate form of human chagasic patients. Initial fibrosis occurred in the three phases but was more severe and frequent in the early chronic. Advanced fibrosis occurred only in the late chronic phase. Tissue parasites occurred only in the acute phase. The digestive tract and skeletal muscles showed mild and occasional lesions. Our data indicate that experimentally infected chagasic rabbits repeat some lesions similar to that of humans chagasic patients, specially that of the indeterminate form. So, it may be a useful, however not an ideal, model.

  9. Investigation into the physiologies of Aeromonas veronii in vitro and inside the digestive tract of the medicinal leech using RNA-seq.

    PubMed

    Bomar, Lindsey; Graf, Joerg

    2012-08-01

    Host-associated microbial communities are widespread in nature and vital to the health and fitness of the host. Deciphering the physiology of the microbiome in vivo is critical to understanding the molecular basis of the symbiosis. Recently, the development and application of high-throughput sequencing techniques, particularly RNA-seq, for studying microbial communities has enabled researchers to address not only which microbes are present in a given community but also how the community functions. For microbes that can also be cultivated in the laboratory, RNA-seq provides the opportunity to identify genes that are differentially expressed during symbiosis by comparing in vitro to in vivo transcriptomes. In the current study, we used RNA-seq to identify genes expressed by the digestive-tract microbiome of the medicinal leech, Hirudo verbana, and by one of the two dominant symbionts, Aeromonas veronii, in a rich medium. We used a comparative approach to identify genes differentially expressed during symbiosis and gain insight into the symbiont's physiology in vivo. Notable findings include evidence for the symbionts experiencing environmental stress, performing arginine catabolism, and expressing noncoding RNAs that are implicated in stationary phase survival, a state in which A. veronii persists for months within the host.

  10. Study of gene transfer in vitro and in the digestive tract of gnotobiotic mice from Lactococcus lactis strains to various strains belonging to human intestinal flora.

    PubMed

    Gruzza, M; Fons, M; Ouriet, M F; Duval-Iflah, Y; Ducluzeau, R

    1994-07-01

    The use of genetically modified organisms (GMO) in dairy products requires evaluation of the DNA transfer capacity from such organisms among the human intestinal microflora. Thus, both in vitro and in vivo [in the digestive tract (DT) of mice] transfer from Lactococcus lactis donor strains of the conjugative plasmid pIL205 (CmR) and the non-conjugative plasmid pIL253 (EmR) to: (1) recipient strains isolated from human faecal flora Bacteroides sp., Bifidobacterium sp., Peptostreptococcus sp. (strictly anaerobic bacterial strains) and Enterococcus faecalis, (2) a whole human faecal flora, was studied. In both cases, no gene transfer was observed to strictly anaerobic bacterial strains. DNA transfer was only observed to the E. faecalis strain: in vivo CmR E. faecalis transconjugants were isolated from sequentially multi-associated mice and when the recipient strains associated with the mice, they were a defined mixture of Bacteroides sp., Bifidobacterium sp., Peptostreptococcus sp. and E. faecalis strains. When mice were associated with the whole human faecal flora, the plasmid pIL205 was transferred into some facultative anaerobic streptococci. It was also shown that DNA transfer occurred even when the lactococcal donor strain was transient in the DT of the gnotobiotic host animals.

  11. Temporal and spatial fate of GFP-expressing motile and nonmotile Aeromonas hydrophila in the house fly digestive tract.

    PubMed

    McGaughey, Joseph; Nayduch, Dana

    2009-01-01

    To gain insight into the transmissibility of bacteria by house flies, the temporal and spatial fate of green fluorescent protein (GFP)-expressing motile and nonmotile strains of Aeromonas hydrophila was examined within the alimentary canal. Liquid food consumed by house flies is first stored in the crop and then is regurgitated and/or passed into the midgut. Once within the midgut, food is contained inside a double-layered peritrophic matrix (PM), with the inner layer enveloping digested material and forming fecal pellets for excretion. Between 1 and 12 h after ingestion, and irrespective of motility, live GFP+ A. hydrophila adhered to the luminal surfaces of the crop and inner PM of bacteria-fed flies. However, some nonadherent, motile bacteria moved freely within the PM lumen in the anteromedial midgut, whereas fecal pellets (lysed bacteria) continued passing posteriorly. At 12-24 h, adhered bacteria of both strains were lysed in the distal midgut, compressed into fecal pellets, and excreted. Viable bacteria in the crop visually exceeded numbers within these fecal pellets. Culture recovery at the same time points showed a 1,000-fold increase of viable bacteria at 2 h, presumably in the crop, with a temporal decline thereafter. Further, viable bacteria were recovered from vomit specks and orally contaminated substrates up to 2 h after feeding but never from feces. These results suggest that A. hydrophila is a transient resident of the house fly alimentary canal and is only orally transmissible for a short time after ingestion. Thus, regurgitation may be more significant than fecal transmission in the spread of some house fly transmitted bacterial diseases.

  12. Standardized total tract digestibility of phosphorus in copra meal, palm kernel expellers, palm kernel meal, and soybean meal fed to growing pigs.

    PubMed

    Almaguer, B L; Sulabo, R C; Liu, Y; Stein, H H

    2014-06-01

    Sixty-six barrows (initial BW: 27.4 ± 2.8 kg) were used to determine the standardized total tract digestibility (STTD) of P in copra meal (CM), palm kernel expellers from Indonesia (PKE-IN), palm kernel expellers from Costa Rica (PKE-CR), palm kernel meal from Costa Rica (PKM), and soybean meal (SBM) without or with exogenous phytase. Pigs were housed individually in metabolism cages and allotted to 11 diets with 6 replicate pigs per diet in a generalized randomized block design. Five diets were formulated by mixing cornstarch and sugar with CM, PKE-IN, PKE-CR, PKM, or SBM. Five additional diets, which were identical to the initial 5 diets but supplemented with 800 units of phytase, were also formulated. A P-free diet was used to measure basal endogenous losses of P by the pigs. Feces were collected for 5 d using the marker to marker approach after a 5-d adaptation period. Analyzed total P in CM, PKE-IN, PKE-CR, PKM, and SBM was 0.52, 0.51, 0.53, 0.54, and 0.67%, respectively. Phytate P was 0.22, 0.35, 0.38, 0.32, and 0.44% in CM, PKE-IN, PKE-CR, PKM, and SBM, respectively. Addition of phytase increased (P < 0.05) the apparent total tract digestibility (ATTD) of P from 60.6 to 80.8, 27.3 to 56.5, 32.6 to 59.9, 48.9 to 64.1, and 41.1 to 72.2% in CM, PKE-IN, PKE-CR, PKM, and SBM, respectively. The ATTD of P in CM was greater (P < 0.05) than in any of the other ingredients. The ATTD of P in SBM and PKM was greater (P < 0.05) than in PKE-IN, with PKE-CR being intermediate. The STTD of P increased (P < 0.05) from 70.6 to 90.3, 37.6 to 66.4, 43.2 to 69.9, 57.9 to 73.5, and 49.6 to 81.1% in CM, PKE-IN, PKE-CR, PKM, and SBM, respectively, when microbial phytase was added to the diets. When expressed as a percentage of total P, phytate P concentration in the ingredient negatively affected (P < 0.05) the ATTD of P (107.09 - 1.0564 × % phytate P; R(2) = 87.1) and the STTD of P (116.3 - 1.0487 × % phytate P; R(2) = 89.4). In conclusion, microbial phytase increased P

  13. Standardized total tract digestibility of phosphorus in copra meal, palm kernel expellers, palm kernel meal, and soybean meal fed to growing pigs.

    PubMed

    Almaguer, B L; Sulabo, R C; Liu, Y; Stein, H H

    2014-06-01

    Sixty-six barrows (initial BW: 27.4 ± 2.8 kg) were used to determine the standardized total tract digestibility (STTD) of P in copra meal (CM), palm kernel expellers from Indonesia (PKE-IN), palm kernel expellers from Costa Rica (PKE-CR), palm kernel meal from Costa Rica (PKM), and soybean meal (SBM) without or with exogenous phytase. Pigs were housed individually in metabolism cages and allotted to 11 diets with 6 replicate pigs per diet in a generalized randomized block design. Five diets were formulated by mixing cornstarch and sugar with CM, PKE-IN, PKE-CR, PKM, or SBM. Five additional diets, which were identical to the initial 5 diets but supplemented with 800 units of phytase, were also formulated. A P-free diet was used to measure basal endogenous losses of P by the pigs. Feces were collected for 5 d using the marker to marker approach after a 5-d adaptation period. Analyzed total P in CM, PKE-IN, PKE-CR, PKM, and SBM was 0.52, 0.51, 0.53, 0.54, and 0.67%, respectively. Phytate P was 0.22, 0.35, 0.38, 0.32, and 0.44% in CM, PKE-IN, PKE-CR, PKM, and SBM, respectively. Addition of phytase increased (P < 0.05) the apparent total tract digestibility (ATTD) of P from 60.6 to 80.8, 27.3 to 56.5, 32.6 to 59.9, 48.9 to 64.1, and 41.1 to 72.2% in CM, PKE-IN, PKE-CR, PKM, and SBM, respectively. The ATTD of P in CM was greater (P < 0.05) than in any of the other ingredients. The ATTD of P in SBM and PKM was greater (P < 0.05) than in PKE-IN, with PKE-CR being intermediate. The STTD of P increased (P < 0.05) from 70.6 to 90.3, 37.6 to 66.4, 43.2 to 69.9, 57.9 to 73.5, and 49.6 to 81.1% in CM, PKE-IN, PKE-CR, PKM, and SBM, respectively, when microbial phytase was added to the diets. When expressed as a percentage of total P, phytate P concentration in the ingredient negatively affected (P < 0.05) the ATTD of P (107.09 - 1.0564 × % phytate P; R(2) = 87.1) and the STTD of P (116.3 - 1.0487 × % phytate P; R(2) = 89.4). In conclusion, microbial phytase increased P

  14. Cereal β-glucan alters nutrient digestibility and microbial activity in the intestinal tract of pigs, and lower manure ammonia emission: a meta-analysis.

    PubMed

    Metzler-Zebeli, B U; Zebeli, Q

    2013-07-01

    Cereal β-glucan may be detrimental in pig production because of negative effects on nutrient digestibility, but they may act as functional ingredients by stimulating the intestinal microbiota. This study primarily aimed to investigate relations between dietary β-glucan and nutrient digestibility, intestinal fermentation, and manure NH3 emission in weaned, growing, and finishing pigs. Effects of dietary xylose, NDF, and CP, and pig BW on animal responses were also evaluated. A meta-analytical approach, accounting for inter- and intraexperiment variations, was used to compute prediction models. Data from 26 studies including 107 different dietary treatments with appropriate dietary and physiological measurements were used to parameterize these models. Dietary β-glucan inclusion ranged from 0 to 6.7%. Increasing dietary β-glucan reduced apparent ileal (AID) and total tract digestibility (ATTD) of CP and energy (R(2) = 0.12 to 0.29; P < 0.05), whereas the ATTD of DM was reduced by 10% up to a threshold β-glucan of 3.5%, above which the response became asymptotic (R(2) = 0.34; P < 0.01). Increasing dietary NDF content decreased ATTD of DM and energy, and increasing xylose concentration reduced ATTD of energy and CP (R(2) = 0.24 to 0.85; P < 0.05). Broken-line model indicated that cecal total VFA and butyrate concentrations increased up to a threshold of 2.5 and 1.4% β-glucan in the diet, respectively, above which these responses became asymptotic (R(2) = 0.77 to 0.96; P < 0.05). Ileal butyrate was negatively and colonic iso-butyrate was positively linked to increasing β-glucan concentration (R(2) = 0.17 to 0.41; P < 0.05). Greater β-glucan concentration were negatively related (R(2) = 0.86; P < 0.01) to NH3 emission, indicating a reduction in NH3 emission by one-half with 6% β-glucan. Backward elimination analysis indicated that greater BW of pigs counteracted (P < 0.05) the negative effect of β-glucan on AID of CP and energy and ATTD of DM and CP. Pig BW also

  15. Digestion of kiwifruit fiber.

    PubMed

    Henare, Sharon J; Rutherfurd, Shane M

    2013-01-01

    Dietary fiber affects the digestion and absorption of nutrients in the gastrointestinal tract. Moreover, it is generally believed that fiber largely escapes digestion in the human small intestine and is therefore mainly a substrate for microbial fermentation in the hindgut. Kiwifruit is a food naturally high in dietary fiber, yet the impact of dietary kiwifruit on nutrient availability has not been reported. The digestion of kiwifruit has been investigated but only in in vitro digestion studies. With its naturally high nonstarch polysaccharide content, it would be expected that kiwifruit would possess the characteristics of a good source of fiber for nutrition and health. Kiwifruit contains soluble and nonsoluble fiber components, both of which would be expected to affect the physical attributes of digesta as it transits the gastrointestinal tract. This chapter summarizes fiber digestion in general and current knowledge of kiwifruit fiber digestion in the gastrointestinal tract.

  16. The effect of dietary carbohydrate composition on apparent total tract digestibility, feed mean retention time, nitrogen and water balance in horses.

    PubMed

    Jensen, R B; Austbø, D; Bach Knudsen, K E; Tauson, A-H

    2014-11-01

    A total of four diets with different carbohydrate composition were investigated in a 4×4 Latin square design experiment with four Norwegian Coldblooded trotter horses. The objective of the present study was to increase the fermentable fibre content and reduce the starch intake of the total ration obtained by partly substituting mature hay and barley with sugar beet pulp (SBP), a soluble fibre source. The diets investigated were hay only (HAY), hay (85% of dry matter intake (DMI)) and molassed SBP (15% of DMI) (SBP), hay (68% of DMI) and barley (32% of DMI) (BAR), and hay (68% of DMI), barley (26% of DMI) and SBP (6% of DMI) (BAR+SBP). The feeding level was 18.5, 17.3, 15.7 and 15.7 g DM/kg BW per day for the HAY, SBP, BAR and BAR+SBP diets, respectively. Each diet was fed for 18 days followed by 10 days of data collection, where apparent total tract digestibility (ATTD), total mean retention time (TMRT) of ytterbium-labelled hay, water balance, digestible energy (DE) intake and nitrogen balance were measured. An enzymatic chemical dietary fibre (DF) method was used to get detailed information on the composition and ATTD of the fibre fraction. Inclusion of SBP in the diet increased the ATTD of the constituent sugars galactose and arabinose (P<0.01). Feeding the HAY and SBP diets resulted in a lower TMRT owing to a higher DF intake than the BAR and BAR+SBP diets (P<0.01). There was no difference in water intake between HAY and SBP, but faecal dry matter was lower for HAY than the other diets (P=0.017), indicating that water was more tightly bound to fibre in the HAY diet. The diets were iso-energetic and provided enough DE and protein for light to moderate exercise for a 550 kg horse. In conclusion, this study showed that the DF intake had a larger effect on TMRT than partly substituting hay or barley with SBP, and that highly fermentable pectin-rich soluble DF from SBP maintains high nutrient utilization in horses.

  17. [Anaerobic digestion of lignocellulosic biomass with animal digestion mechanisms].

    PubMed

    Wu, Hao; Zhang, Pan-Yue; Guo, Jian-Bin; Wu, Yong-Jie

    2013-02-01

    Lignocellulosic material is the most abundant renewable resource in the earth. Herbivores and wood-eating insects are highly effective in the digestion of plant cellulose, while anaerobic digestion process simulating animal alimentary tract still remains inefficient. The digestion mechanisms of herbivores and wood-eating insects and the development of anaerobic digestion processes of lignocellulose were reviewed for better understanding of animal digestion mechanisms and their application in design and operation of the anaerobic digestion reactor. Highly effective digestion of lignocellulosic materials in animal digestive system results from the synergistic effect of various digestive enzymes and a series of physical and biochemical reactions. Microbial fermentation system is strongly supported by powerful pretreatment, such as rumination of ruminants, cellulase catalysis and alkali treatment in digestive tract of wood-eating insects. Oxygen concentration gradient along the digestive tract may stimulate the hydrolytic activity of some microorganisms. In addition, the excellent arrangement of solid retention time, digesta flow and end product discharge enhance the animal digestion of wood cellulose. Although anaerobic digestion processes inoculated with rumen microorganisms based rumen digestion mechanisms were developed to treat lignocellulose, the fermentation was more greatly limited by the environmental conditions in the anaerobic digestion reactors than that in rumen or hindgut. Therefore, the anaerobic digestion processes simulating animal digestion mechanisms can effectively enhance the degradation of wood cellulose and other organic solid wastes.

  18. Effects of dietary lipid sources on performance and apparent total tract digestibility of lipids and energy when fed to nursery pigs.

    PubMed

    Mendoza, S M; van Heugten, E

    2014-02-01

    Acidulated fats and oils are by-products of the fat-refining industry. They contain high levels of FFA and are 10% to 20% less expensive than refined fats and oils. Two studies were designed to measure the effects of dietary lipid sources low or high in FFA on growth performance and apparent total tract digestibility (ATTD) of lipids and GE in nursery pigs. In Exp. 1, 189 pigs at 14 d postweaning (BW of 9.32 ± 0.11 kg) were used for 21 d with 9 replicate pens per treatment and 3 pigs per pen. Dietary treatments consisted of a control diet without added lipids and 6 diets with 6% inclusion of lipids. Four lipid sources were combined to create the dietary treatments with 2 levels of FFA (0.40% or 54.0%) and 3 degrees of fat saturation (iodine value [IV] = 77, 100, or 123) in a 2 × 3 factorial arrangement. Lipid sources were soybean oil (0.3% FFA and IV = 129.4), soybean-cottonseed acid oil blend (70.5% FFA and IV = 112.9), choice white grease (0.6% FFA and IV = 74.8), and choice white acid grease (56.0% FFA and IV = 79.0). Addition of lipid sources decreased ADFI (810 vs. 872 g/d; P = 0.018) and improved G:F (716 vs. 646 g/kg; P < 0.001). Diets high in FFA tended (P = 0.08) to improve final BW (21.35 vs. 21.01 kg) and ADG (576 vs. 560 g/d). Lipid-supplemented diets had greater ATTD of lipids than control diets (67.4% vs. 29.7%; P < 0.001). Apparent total tract digestibility of lipids was greater in diets with low FFA (69.9% vs. 64.9%; P < 0.001) and decreased linearly with increasing IV (73.2%, 69.1%, and 67.2%). For GE, ATTD was greater in diets with low FFA (83.1% vs. 80.9%; P = 0.001). In Exp. 2, 252 pigs at 7 d postweaning (BW of 7.0 ± 0.2 kg) were used for 28 d with 9 replicate pens per treatment and 4 pigs per pen. Diets included a control diet without added lipids and 6 treatments with 2.5%, 5.0%, or 7.5% of lipids from either poultry fat (1.9% FFA) or acidulated poultry fat (37.8% FFA) in a 2 × 3 factorial arrangement. Addition of lipids increased (P < 0

  19. Effects of microbial phytase on the apparent and standardized total tract digestibility of phosphorus in rice coproducts fed to growing pigs.

    PubMed

    Casas, G A; Stein, H H

    2015-07-01

    The objectives of this experiment were to determine the apparent total tract digestibility (ATTD) and the standardized total tract digestibility (STTD) of P and the effect of microbial phytase on ATTD and STTD of P in full-fat rice bran (FFRB), defatted rice bran (DFRB), brown rice, broken rice, and rice mill feed when fed to pigs. Ninety-six barrows (initial BW of 19.4 ± 1.4 kg) were allotted to 12 diets with 8 replicate pigs per diet in a randomized complete block design. A basal diet based on corn and soybean meal was formulated. Five additional diets containing corn, soybean meal, and each rice coproduct were also formulated, and the ratio between corn and soybean meal in these diets was similar to that in the basal diet. Six additional diets that were similar to the initial 6 diets with the exception that 1,000 units of microbial phytase were added to the diets were also formulated. The ATTD and STTD of P were calculated for each diet using the direct procedure, and the ATTD and STTD of P in each rice coproduct were calculated using the difference procedure. Results of the experiment indicated that the concentration of P in feces was reduced (P < 0.05) from pigs fed diets with microbial phytase compared with pigs fed diets without phytase. No differences were observed between the basal diet and the broken rice diet, but the ATTD and the STTD of P in those diets was greater (P < 0.05) than in all other diets both without and with phytase. Among the rice coproducts, the greatest (P < 0.05) ATTD and STTD of P were observed for broken rice regardless of inclusion of phytase. If no microbial phytase was used, the values for STTD of P in brown rice, FFRB, DFRB, and rice mill feed were not different, but if microbial phytase was included in the diet, ATTD and STTD of P in brown rice was greater (P < 0.05) than in FFRB, DFRB, and rice mill feed. The STTD of P in brown rice, FFRB, and rice mill feed was greater (P < 0.05) if microbial phytase was used than if no

  20. Effect of a grain challenge on ruminal, urine, and fecal pH, apparent total-tract starch digestibility, and milk composition of Holstein and Jersey cows.

    PubMed

    Luan, S; Cowles, K; Murphy, M R; Cardoso, F C

    2016-03-01

    The effects of a grain challenge on ruminal, urine, and fecal pH, apparent total-tract starch digestibility, and milk composition were determined. Six Holstein cows, 6 rumen-cannulated Holstein cows, and 6 Jersey cows were used in a replicated 3 × 3 Latin square design balanced to measure carryover effects. Periods (10 d) were divided into 4 stages (S): S1, d 1 to 3, served as baseline with regular total mixed ration ad libitum; S2, d 4, served as restricted feeding, with cows offered 50% of the total mixed ration fed on S1 (dry matter basis); S3, d 5, a grain challenge was performed, in which cows were fed total mixed ration ad libitum and not fed (CON) or fed an addition of 10% (MG) or 20% (HG) pellet wheat-barley (1:1) top-dressed onto the total mixed ration, based on dry matter intake obtained in S1; S4, d 6 to 10, served as recovery stage with regular total mixed ration fed ad libitum. Overall, cows had a quadratic treatment effect for milk yield where CON (22.6 kg/d) and HG (23.5 kg/d) had lower milk yield than cows in MG (23.7 kg/d). Jersey cows had a quadratic treatment effect for dry matter intake where cows in CON (13.2 kg/d) and HG (12.4 kg/d) had lower dry matter intake than cows in MG (14 kg/d). Holstein cows had a linear treatment effect for dry matter intake (17.7, 18.4, and 18.6 kg/d for CON, MG, and HG, respectively). Rumen pH for the rumen-cannulated cows had a linear treatment effect (6.45, 6.35, and 6.24 for CON, MG, and HG, respectively). Cows in HG spent more time with rumen pH below 5.8 (4.33 h) than MG (2 h) or CON (2.17 h) as shown by the quadratic treatment effect. Holstein cows in HG (8.46) had lower urine pH than MG (8.51) or CON (8.54) as showed by the linear treatment effect for urine pH. Apparent total-tract starch digestibility had a tendency for a linear treatment effect on S3 (97.62 ± 1.5, 97.47 ± 1.5, and 91.84 ± 1.6%, for CON, MG, and HG, respectively). Fecal pH was associated with rumen pH depression as early as 15 h after

  1. Mucinivorans hirudinis gen. nov., sp. nov., an anaerobic, mucin-degrading bacterium isolated from the digestive tract of the medicinal leech Hirudo verbana

    PubMed Central

    Nelson, Michael C.; Bomar, Lindsey; Maltz, Michele

    2015-01-01

    Three anaerobic bacterial strains were isolated from the digestive tract of the medicinal leech Hirudo verbana, using mucin as the primary carbon and energy source. These strains, designated M3T, M4 and M6, were Gram-stain-negative, non-spore-forming and non-motile. Cells were elongated bacilli approximately 2.4 µm long and 0.6 µm wide. Growth only occurred anaerobically under mesophilic and neutral pH conditions. All three strains could utilize multiple simple and complex sugars as carbon sources, with glucose fermented to acid by-products. The DNA G+C contents of strains M3T, M4 and M6 were 44.9, 44.8 and 44.8 mol%, respectively. The major cellular fatty acid of strain M3T was iso-C15 : 0. Phylogenetic analysis of full-length 16S rRNA gene sequences revealed that the three strains shared >99 % similarity with each other and represent a new lineage within the family Rikenellaceae of the order Bacteroidales, phylum Bacteroidetes. The most closely related bacteria to strain M3T based on 16S rRNA gene sequences were Rikenella microfusus DSM 15922T (87.3 % similarity) and Alistipes finegoldii AHN 2437T (87.4 %). On the basis of phenotypic, genotypic and physiological evidence, strains M3T, M4 and M6 are proposed as representing a novel species of a new genus within the family Rikenellaceae, for which the name Mucinivorans hirudinis gen. nov., sp. nov. is proposed. The type strain of Mucinivorans hirudinis is M3T ( = ATCC BAA-2553T = DSM 27344T). PMID:25563920

  2. Impact of selective digestive decontamination on respiratory tract Candida among patients with suspected ventilator-associated pneumonia. A meta-analysis.

    PubMed

    Hurley, J C

    2016-07-01

    The purpose here is to establish the incidence of respiratory tract colonization with Candida (RT Candida) among ICU patients receiving mechanical ventilation within studies in the literature. Also of interest is its relationship with candidemia and the relative importance of topical antibiotic (TA) use as within studies of selective digestive decontamination (SDD) versus other candidate risk factors towards it. The incidence of RT Candida was extracted from component (control and intervention) groups decanted from studies of various TA and non-TA ICU infection prevention methods with summary estimates derived using random effects. A benchmark RT Candida incidence to provide overarching calibration was derived using (observational) groups from studies without any prevention method under study. A multi-level regression model of group level data was undertaken using generalized estimating equation (GEE) methods. RT Candida data were sourced from 113 studies. The benchmark RT Candida incidence is 1.3; 0.9-1.8 % (mean and 95 % confidence intervals). Membership of a concurrent control group of a study of SDD (p = 0.02), the group-wide presence of candidemia risk factors (p < 0.001), and proportion of trauma admissions (p = 0.004), but neither the year of study publication, nor membership of any other component group, nor the mode of respiratory sampling are predictive of the RT Candida incidence. RT Candida and candidemia incidences are correlated. RT Candida incidence can serve as a basis for benchmarking. Several relationships have been identified. The increased incidence among concurrent control groups of SDD studies cannot be appreciated in any single study examined in isolation.

  3. Digestive development of the early-weaned pig. 1. Effect of continuous nutrient supply on the development of the digestive tract and on changes in digestive enzyme activity during the first week post-weaning.

    PubMed

    Kelly, D; Smyth, J A; McCracken, K J

    1991-03-01

    Gastric intubation was adopted to examine the effect of continuous nutrient supply on digestive development of the pig during the immediate post-weaning period. The 14 d-weaned animals were slaughtered at 3, 5 and 7 d post-weaning (3W, 5W and 7W respectively) and the suckled animals were slaughtered at 14 and 22 d of age (14SR and 22SR respectively). The weight of the pancreas (g/kg bodyweight) was significantly greater (P less than 0.05) in the 5W and 7W groups, as was the weight of large intestine (g/kg) in all weaned groups (P less than 0.01) compared with sow-reared pigs. The stomach weight (g/kg) tended to be greater in the weaned groups. Weaning, in conjunction with a continuous nutrient supply, did not significantly alter the time-related changes in the weight of the small intestine (SI) or the SI mucosa, although both variables tended to be lowest in the 3W group. However, there was a 20% reduction in the protein content of the mucosa within the first 3 d post-weaning (P less than 0.01) which persisted during the 7 d experimental period. Lactase, (beta-galactosidase; EC 3.2.1.23) activity (mumol/g protein and mol/d) of the 7W group was reduced to approximately 40% of the 22SR value. Hence, continuous nutrient supply may have delayed, but did not prevent, the loss of lactase activity at weaning. The activity of sucrase (sucrose-alpha-glucosidase; EC 3.2.1.48) was significantly higher in 22SR compared with 14SR animals. Sucrase activity in weaned pigs was intermediate to the values for sow-reared pigs whereas maltase (alpha-glucosidase; EC 3.2.1.20) and glucoamylase (glucan 1,4-alpha-glucosidase; EC 3.2.1.3) were significantly increased in relation to their sow-reared counterparts. Continuous nutrient supply did not prevent the reduction in villous height and the crypt hypertrophy associated with weaning. The results of the present study suggest that there may be some degree of interaction between nutrient intake and gut development during the immediate post

  4. Aero-optimum hovering kinematics.

    PubMed

    Nabawy, Mostafa R A; Crowther, William J

    2015-08-07

    Hovering flight for flapping wing vehicles requires rapid and relatively complex reciprocating movement of a wing relative to a stationary surrounding fluid. This note develops a compact analytical aero-kinematic model that can be used for optimization of flapping wing kinematics against aerodynamic criteria of effectiveness (maximum lift) and efficiency (minimum power for a given amount of lift). It can also be used to make predictions of required flapping frequency for a given geometry and basic aerodynamic parameters. The kinematic treatment is based on a consolidation of an existing formulation that allows explicit derivation of flapping velocity for complex motions whereas the aerodynamic model is based on existing quasi-steady analysis. The combined aero-kinematic model provides novel explicit analytical expressions for both lift and power of a hovering wing in a compact form that enables exploration of a rich kinematic design space. Good agreement is found between model predictions of flapping frequency and observed results for a number of insects and optimal hovering kinematics identified using the model are consistent with results from studies using higher order computational models. For efficient flight, the flapping angle should vary using a triangular profile in time leading to a constant velocity flapping motion, whereas for maximum effectiveness the shape of variation should be sinusoidal. For both cases the wing pitching motion should be rectangular such that pitch change at stroke reversal is as rapid as possible.

  5. Aero-optimum hovering kinematics.

    PubMed

    Nabawy, Mostafa R A; Crowther, William J

    2015-08-01

    Hovering flight for flapping wing vehicles requires rapid and relatively complex reciprocating movement of a wing relative to a stationary surrounding fluid. This note develops a compact analytical aero-kinematic model that can be used for optimization of flapping wing kinematics against aerodynamic criteria of effectiveness (maximum lift) and efficiency (minimum power for a given amount of lift). It can also be used to make predictions of required flapping frequency for a given geometry and basic aerodynamic parameters. The kinematic treatment is based on a consolidation of an existing formulation that allows explicit derivation of flapping velocity for complex motions whereas the aerodynamic model is based on existing quasi-steady analysis. The combined aero-kinematic model provides novel explicit analytical expressions for both lift and power of a hovering wing in a compact form that enables exploration of a rich kinematic design space. Good agreement is found between model predictions of flapping frequency and observed results for a number of insects and optimal hovering kinematics identified using the model are consistent with results from studies using higher order computational models. For efficient flight, the flapping angle should vary using a triangular profile in time leading to a constant velocity flapping motion, whereas for maximum effectiveness the shape of variation should be sinusoidal. For both cases the wing pitching motion should be rectangular such that pitch change at stroke reversal is as rapid as possible. PMID:26248884

  6. The effects of feeding time on milk production, total-tract digestibility, and daily rhythms of feeding behavior and plasma metabolites and hormones in dairy cows.

    PubMed

    Niu, M; Ying, Y; Bartell, P A; Harvatine, K J

    2014-12-01

    The timing of feed intake entrains circadian rhythms regulated by internal clocks in many mammals. The objective of this study was to determine if the timing of feeding entrains daily rhythms in dairy cows. Nine Holstein cows were used in a replicated 3 × 3 Latin square design with 14-d periods. An automated system recorded the timing of feed intake over the last 7 d of each period. Treatments were feeding 1×/d at 0830 h (AM) or 2030 h (PM) and feeding 2×/d in equal amounts at 0830 and 2030 h. All treatments were fed at 110% of daily intake. Cows were milked 2×/d at 0500 and 1700 h. Milk yield and composition were not changed by treatment. Daily intake did not differ, but twice-daily feeding tended to decrease total-tract digestibility of organic matter and neutral detergent fiber (NDF). A treatment by time of day interaction was observed for feeding behavior. The amount of feed consumed in the first 2h after feeding was 70% greater for PM compared with AM feeding. A low rate of intake overnight (2400 to 0500 h; 2.2 ± 0.74% daily intake/h, mean ± SD) and a moderate rate of intake in the afternoon (1200 to 1700 h; 4.8 ± 1.1% daily intake/h) was noted for all treatments, although PM slightly reduced the rate during the afternoon period compared with AM. A treatment by time of day interaction was seen for fecal NDF and indigestible NDF (iNDF) concentration, blood urea nitrogen, plasma glucose and insulin concentrations, body temperature, and lying behavior. Specifically, insulin increased and glucose decreased more after evening feeding than after morning feeding. A cosine function within a 24-h period was used to characterize daily rhythms using a random regression. Rate of feed intake during spontaneous feeding, fecal NDF and iNDF concentration, plasma glucose, insulin, NEFA, body temperature, and lying behavior fit a cosine function within a 24-h period that was modified by treatment. In conclusion, feeding time can reset the daily rhythms of feeding and

  7. Effect of dietary coarsely ground corn on broiler live performance, gastrointestinal tract development, apparent ileal digestibility of energy and nitrogen, and digesta particle size distribution and retention time

    PubMed Central

    Xu, Y.; Stark, C. R.; Ferket, P. R.; Williams, C. M.; Pacheco, W. J.; Brake, J.

    2015-01-01

    Dietary structural material has been reported to improve broiler live performance and gastrointestinal tract (GIT) function. In this 50 d cage study, the effects of coarsely ground corn (CC) inclusion on broiler live performance, GIT development, apparent ileal digestibility (AID) of energy and nitrogen (N), and digesta particle size distribution and retention time were investigated. This study included 3 CC inclusions (0, 25, and 50% fine corn [FC] replaced by CC), with 6 replicate cages of 10 birds per treatment. The feed conversion ratio (FCR) at 35 and 42 d was improved (P < 0.01) as the dietary inclusion of CC increased without effect on feed intake. The 50% CC diet increased absolute and relative gizzard weight at 42 d of age as compared to diets with 0 and 25% CC (P < 0.01). Dietary CC increased absolute proventriculus weight at 28 d of age (P < 0.05). A numerically lower gizzard digesta pH (P < 0.08) was observed at 28 d but not 42 d of age, and there was no difference in proventriculus, jejunum, or ileum digesta pH at 28 or 42 d of age. The 25 and 50% CC treatments increased the digesta retention time at 30 and 45 d of age (P < 0.05 and P < 0.01, respectively). The 25 and 50% CC treatments improved AID of energy by 7.1 and 8.2%, respectively, when compared with the 0% CC treatment, and they improved AID of N by 12.2 and 12.4%, respectively (P < 0.01). The digesta particles in the jejunum exhibited a similar distribution, with a dgw (geometric mean diameter by mass) of 218, 204, and 181 μm when 0, 25, of 50% CC diets were consumed, respectively. In conclusion, birds fed pelleted and screened diets that contained 25 and 50% CC exhibited increased BW, improved FCR, and increased AID of energy and N, which was probably due to enhanced gizzard development and greater digesta retention time. PMID:25568134

  8. AeroMACS System Characterization and Demonstrations

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Apaza, Rafael D.; Dimond, Robert P.

    2013-01-01

    The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past three years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

  9. AeroMACS System Characterization and Demonstrations

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Apaza, Rafael D.; Dimond, Robert P.

    2013-01-01

    This The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past 3 years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

  10. AeroMACS system characterization and demonstrations

    NASA Astrophysics Data System (ADS)

    Kerczewski, R. J.; Apaza, R. D.; Dimond, R. P.

    This The Aeronautical Mobile Airport Communications System (AeroMACS) is being developed to provide a new broadband wireless communications capability for safety critical communications in the airport surface domain, providing connectivity to aircraft and other ground vehicles as well as connections between other critical airport fixed assets. AeroMACS development has progressed from requirements definition through technology definition, prototype deployment and testing, and now into national and international standards development. The first prototype AeroMACS system has been deployed at the Cleveland Hopkins International Airport (CLE) and the adjacent NASA Glenn Research Center (GRC). During the past three years, extensive technical testing has taken place to characterize the performance of the AeroMACS prototype and provide technical support for the standards development process. The testing has characterized AeroMACS link and network performance over a variety of conditions for both fixed and mobile data transmission and has included basic system performance testing and fixed and mobile applications testing. This paper provides a summary of the AeroMACS performance testing and the status of standardization activities that the testing supports.

  11. Engineering Digestion: Multiscale Processes of Food Digestion.

    PubMed

    Bornhorst, Gail M; Gouseti, Ourania; Wickham, Martin S J; Bakalis, Serafim

    2016-03-01

    Food digestion is a complex, multiscale process that has recently become of interest to the food industry due to the developing links between food and health or disease. Food digestion can be studied by using either in vitro or in vivo models, each having certain advantages or disadvantages. The recent interest in food digestion has resulted in a large number of studies in this area, yet few have provided an in-depth, quantitative description of digestion processes. To provide a framework to develop these quantitative comparisons, a summary is given here between digestion processes and parallel unit operations in the food and chemical industry. Characterization parameters and phenomena are suggested for each step of digestion. In addition to the quantitative characterization of digestion processes, the multiscale aspect of digestion must also be considered. In both food systems and the gastrointestinal tract, multiple length scales are involved in food breakdown, mixing, absorption. These different length scales influence digestion processes independently as well as through interrelated mechanisms. To facilitate optimized development of functional food products, a multiscale, engineering approach may be taken to describe food digestion processes. A framework for this approach is described in this review, as well as examples that demonstrate the importance of process characterization as well as the multiple, interrelated length scales in the digestion process.

  12. Engineering Digestion: Multiscale Processes of Food Digestion.

    PubMed

    Bornhorst, Gail M; Gouseti, Ourania; Wickham, Martin S J; Bakalis, Serafim

    2016-03-01

    Food digestion is a complex, multiscale process that has recently become of interest to the food industry due to the developing links between food and health or disease. Food digestion can be studied by using either in vitro or in vivo models, each having certain advantages or disadvantages. The recent interest in food digestion has resulted in a large number of studies in this area, yet few have provided an in-depth, quantitative description of digestion processes. To provide a framework to develop these quantitative comparisons, a summary is given here between digestion processes and parallel unit operations in the food and chemical industry. Characterization parameters and phenomena are suggested for each step of digestion. In addition to the quantitative characterization of digestion processes, the multiscale aspect of digestion must also be considered. In both food systems and the gastrointestinal tract, multiple length scales are involved in food breakdown, mixing, absorption. These different length scales influence digestion processes independently as well as through interrelated mechanisms. To facilitate optimized development of functional food products, a multiscale, engineering approach may be taken to describe food digestion processes. A framework for this approach is described in this review, as well as examples that demonstrate the importance of process characterization as well as the multiple, interrelated length scales in the digestion process. PMID:26799793

  13. Apparent total tract energy and macronutrient digestibility and fecal fermentative end-product concentrations of domestic cats fed extruded, raw beef-based, and cooked beef-based diets.

    PubMed

    Kerr, K R; Vester Boler, B M; Morris, C L; Liu, K J; Swanson, K S

    2012-02-01

    The objectives of this study were to determine differences in apparent total tract energy and macronutrient digestibility, fecal and urine characteristics, and serum chemistry of domestic cats fed raw and cooked meat-based diets and extruded diet. Nine adult female domestic shorthair cats were utilized in a replicated 3 × 3 Latin square design. Dietary treatments included a high-protein extruded diet (EX; 57% CP), a raw beef-based diet (RB; 53% CP), and a cooked beef-based diet (CB; 52% CP). Cats were housed individually in metabolic cages and fed to maintain BW. The study consisted of three 21-d periods. Each period included diet adaptation during d 0 to 16; fecal and urine sample collections during d 17 to 20; and blood sample collection at d 21. Food intake was measured daily. Total feces and urine were collected for determination of nutrient digestibility. In addition, a fresh urine sample was collected from each cat for urinalysis, and a fresh fecal sample was collected from each cat for determination of DM percentage and ammonia, short-chain fatty acid (SCFA), and branched-chain fatty acid (BCFA) concentrations. All feces were scored after collection using a scale ranging from 1 (hard, dry pellets) to 5 (watery, liquid that can be poured). Blood was analyzed for serum metabolites. Apparent total tract DM, OM, CP, fat, and GE digestibilities were greater (P ≤ 0.05) in cats fed RB and CB than those fed EX. Total fecal SCFA concentrations did not differ among dietary treatments; however, molar ratios of SCFA were modified by diet, with cats fed RB and CB having an increased (P ≤ 0.05) proportion of fecal propionate and decreased (P ≤ 0.05) proportion of fecal butyrate compared with cats fed EX. Fecal concentrations of ammonia, isobutyrate, valerate, isovalerate, and total BCFA were greater (P ≤ 0.05) in cats fed EX compared with cats fed RB and CB. Our results indicated that cooking a raw meat diet does not alter apparent total tract energy and

  14. Monitoring of the Parasite Load in the Digestive Tract of Rhodnius prolixus by Combined qPCR Analysis and Imaging Techniques Provides New Insights into the Trypanosome Life Cycle

    PubMed Central

    Dias, Felipe de Almeida; Guerra, Barbara; Vieira, Larissa Rezende; Perdomo, Hugo Diego; Gandara, Ana Caroline Paiva; do Amaral, Raquel Juliana Vionette; Vollú, Renata Estebanez; Gomes, Suzete Araujo Oliveira; Lara, Flavio Alves; Sorgine, Marcos Henrique Ferreira; Medei, Emiliano; de Oliveira, Pedro Lagerblad; Salmon, Didier

    2015-01-01

    Background Here we report the monitoring of the digestive tract colonization of Rhodnius prolixus by Trypanosoma cruzi using an accurate determination of the parasite load by qPCR coupled with fluorescence and bioluminescence imaging (BLI). These complementary methods revealed critical steps necessary for the parasite population to colonize the insect gut and establish vector infection. Methodology/Principal Findings qPCR analysis of the parasite load in the insect gut showed several limitations due mainly to the presence of digestive-derived products that are thought to degrade DNA and inhibit further the PCR reaction. We developed a real-time PCR strategy targeting the T. cruzi repetitive satellite DNA sequence using as internal standard for normalization, an exogenous heterologous DNA spiked into insect samples extract, to precisely quantify the parasite load in each segment of the insect gut (anterior midgut, AM, posterior midgut, PM, and hindgut, H). Using combined fluorescence microscopy and BLI imaging as well as qPCR analysis, we showed that during their journey through the insect digestive tract, most of the parasites are lysed in the AM during the first 24 hours independently of the gut microbiota. During this short period, live parasites move through the PM to establish the onset of infection. At days 3–4 post-infection (p.i.), the parasite population begins to colonize the H to reach a climax at day 7 p.i., which is maintained during the next two weeks. Remarkably, the fluctuation of the parasite number in H remains relatively stable over the two weeks after refeeding, while the populations residing in the AM and PM increases slightly and probably constitutes the reservoirs of dividing epimastigotes. Conclusions/Significance These data show that a tuned dynamic control of the population operates in the insect gut to maintain an equilibrium between non-dividing infective trypomastigote forms and dividing epimastigote forms of the parasite, which is

  15. Resolution requirements for aero-optical simulations

    SciTech Connect

    Mani, Ali Wang Meng; Moin, Parviz

    2008-11-10

    Analytical criteria are developed to estimate the error of aero-optical computations due to inadequate spatial resolution of refractive index fields in high Reynolds number flow simulations. The unresolved turbulence structures are assumed to be locally isotropic and at low turbulent Mach number. Based on the Kolmogorov spectrum for the unresolved structures, the computational error of the optical path length is estimated and linked to the resulting error in the computed far-field optical irradiance. It is shown that in the high Reynolds number limit, for a given geometry and Mach number, the spatial resolution required to capture aero-optics within a pre-specified error margin does not scale with Reynolds number. In typical aero-optical applications this resolution requirement is much lower than the resolution required for direct numerical simulation, and therefore, a typical large-eddy simulation can capture the aero-optical effects. The analysis is extended to complex turbulent flow simulations in which non-uniform grid spacings are used to better resolve the local turbulence structures. As a demonstration, the analysis is used to estimate the error of aero-optical computation for an optical beam passing through turbulent wake of flow over a cylinder.

  16. Apparent total tract energy and macronutrient digestibility of one- to three-day-old, adult ground, extruded, and canned chicken-based diets in domestic cats (Felis silvestris catus).

    PubMed

    Kerr, K R; Morris, C L; Burke, S L; Swanson, K S

    2014-08-01

    There has been a recent increase in the popularity of feeding unconventional diets, including whole prey diets, to domestic cats (Felis silvestris catus). Data are needed that allow animal caretakers to choose and formulate diets that meet the nutritional requirements of their cats. Our objective was to evaluate the effects of feeding 1- to 3-d-old whole chicks (WHO), ground adult chicken product (GRO), a chicken-based canned diet (CAN), and a chicken-based extruded diet (EXT) on apparent total tract energy and macronutrient digestibility, N balance, and blood metabolites of domestic cats (n = 11). Macronutrient, energy, and moisture concentrations of diets varied greatly (e.g., CP: 35 to 72% DM); however, cats fed all diets maintained BW and N balance. In general, cats fed WHO had lower nutrient digestibility than those fed CAN and EXT. Cats fed GRO had greater nutrient digestibility than cats fed commercial diets. For example, apparent OM and GE digestibility coefficients were greater (P ≤ 0.05) for cats fed CAN (86 and 88%, respectively), EXT (88 and 88%), and GRO (94 and 95%) compared with those fed WHO (83 and 83%) and greater (P ≤ 0.05) for cats fed GRO compared with those fed CAN and EXT. Many blood metabolites were modified by diet, but most remained within reference ranges for domestic cats. Serum cholesterol was elevated above the reference range for all treatments and greater (P ≤ 0.05) for cats fed WHO compared with those fed CAN, EXT, and GRO. Serum creatinine concentrations were above the reference range for all treatments and greater (P ≤ 0.05) for cats fed GRO compared with those fed CAN or WHO. These data indicate that the whole prey tested herein maintained short-term health and are adequately digestible for use in companion animal diets. Research is needed to determine the global and long-term health implications of feeding whole or ground diets to domestic cats, which may be different in terms of macronutrient, energy, and moisture

  17. The digestive system: part 1.

    PubMed

    Johnstone, Carolyn; Hendry, Charles; Farley, Alistair; McLafferty, Ella

    This article, which forms part of the life sciences series and is the first of two articles on the digestive system, explores the structure and function of the digestive system. It is important that nurses understand how the digestive system works and its role in maintaining health. The article describes the gross structure of the gastrointestinal tract along with relevant physiology. It also outlines several disorders of the gastrointestinal tract and their treatment and nursing management. The second article will explain the liver, pancreas and gall bladder and their digestive functions, and provides a brief overview of the disorders of chronic liver disease, pancreatitis and gallstones.

  18. Feeding fat from distillers dried grains with solubles to dairy heifers: I. Effects on growth performance and total tract digestibility of nutrients

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to determine if increased dietary fat from dried distillers grains with solubles (DDGS) in diets of growing heifers affected dry matter intake (DMI), average daily gain (ADG), growth performance, and nutrient digestibility. Thirty-three Holstein heifers (133 ± 18 d ol...

  19. Early upper digestive tract side effects of zidovudine with tenofovir plus emtricitabine in West African adults with high CD4 counts

    PubMed Central

    Ouattara, Eric; Danel, Christine; Moh, Raoul; Gabillard, Delphine; Peytavin, Gilles; Konan, Romuald; Carrou, Jérome Le; Bohoussou, Franck; Eholie, Serge P; Anglaret, Xavier

    2013-01-01

    Introduction Tenofovir (TDF) with emtricitabine (FTC) and zidovudine (ZDV) is a recognized alternate first-line antiretroviral (ART) regimen for patients who cannot start treatment with non-nucleoside reverse transcriptase inhibitors (NNRTIs). Clinical studies comparing TDF+FTC+ZDV to other regimens are lacking. Methods Participants in a trial of early ART in Côte d'Ivoire (Temprano ANRS 12136) started treatment with TDF/FTC plus either efavirenz (EFV) or ZDV (HIV-1+2 dually infected patients and women refusing contraception or previously treated with nevirapine). We compared rates of upper digestive serious adverse events (sAEs) between TDF/FTC+EFV and TDF/FTC+ZDV patients during the first six months of treatment. sAEs were defined as either grade 3–4 AEs or persistent grade 1–2 AEs leading to drug discontinuation. Results A total of 197 patients (76% women, median CD4 count 395/mm3) started therapy with TDF/FTC, 126 with EFV and 71 with ZDV. During the first six months of ART, 94 patients had digestive AEs (nausea/vomiting) of any grade (EFV 36/126, 29%; ZDV 58/71, 82%, p<0.0001), including 20 sAEs (EFV 3/126, 5%; ZDV 17/71, 24%, p<0.0001). In-patients on TDF/FTC+ZDV with digestive AEs, the median time to the first symptom was two days (IQR: 1–4). Plasma ZDV (Cmax) distributions and pill ZDV dosages were normal. Patients with digestive AEs had higher haemoglobin levels and tended to have higher body mass indices and more frequent past histories of cotrimoxazole (CTX) prophylaxis. Conclusions We observed an unexpectedly high rate of digestive sAEs in West African adults, mostly women, who started a 3-nuc ART with TDF/FTC+ZDV in Côte d'Ivoire. These adults were participating in a trial of early ART and had much higher CD4 counts than those who currently routinely start ART in sub-Saharan Africa. They all received CTX concomitantly with ZDV. We suggest that further early prescriptions of TDF+XTC+ZDV should be carefully monitored and that whenever possible

  20. Apparent total tract digestibility of dietary calcium and phosphorus and their efficiency in bone mineral retention are affected by body mineral status in growing pigs.

    PubMed

    Létourneau-Montminy, M P; Lovatto, P A; Pomar, C

    2014-09-01

    Improving dietary P utilization without modifying pig performance is crucial for production sustainability. A feeding program comprising three 28-d phases (20 to 40, 40 to 70, and 70 to 100 kg) was used to feed 72 pigs with an initial BW of 20 kg. The ability of the pigs to modify the digestive and metabolic utilization of P when fed either a control (CON) diet or a low-P (LOW) diet providing 40% less digestible P with a constant Ca:digestible P was studied using different sequences of dietary P and Ca restriction (i.e., depletion [LOW]) and recovery (i.e., repletion [CON]), namely CON-CON-CON, CON-CON-LOW, CON-LOW-LOW, LOW-CON-CON, LOW-LOW-CON, and LOW-LOW-LOW. Bone mineral content (BMC) was measured in the lumbar region (L2-L4) by dual-energy X-ray absorptiometry at the beginning and end of each feeding phase. Total feces and urine were collected during phases 2 and 3. At the end of phase 1, BMC was lower in the LOW pigs than in the C pigs (29%; P < 0.001). During phase 2, the BMC gain was greater in the LOW-CON pigs than in the CON-CON pigs (16%; P < 0.001). During phase 3, the LOW-LOW-CON pigs absorbed 26% more Ca (P < 0.001) and retained 56% more BMC (P < 0.001) than the CON-CON-CON pigs did. Digestive and metabolic adaptations allowed the LOW-LOW-CON and LOW-CON-CON pigs to reach BMC similar to that of the CON-CON-CON pigs. These metabolic adaptations are promising, but practical applications of these results requires a better understanding of the underlying mechanisms to fine-tune the degree of depletion, pig age, and the duration of P and Ca depletion and repletion periods.

  1. Upon exposure to Cu nanoparticles, accumulation of copper in the isopod Porcellio scaber is due to the dissolved Cu ions inside the digestive tract.

    PubMed

    Golobič, Miha; Jemec, Anita; Drobne, Damjana; Romih, Tea; Kasemets, Kaja; Kahru, Anne

    2012-11-01

    The fate of nanoparticles in organisms is of significant interest. In the current work, we used a test system with terrestrial isopods (Porcellio scaber) fed with food spiked with Cu NPs or soluble Cu salt for 14 days. Two different doses were used for spiking to yield final concentrations of 2000 and 5000 μg Cu/g dry food. After the exposure period, part of the exposed group of animals was transferred to clean food to depurate. Cu content was analyzed in the digestive glands, gut, and the 'rest' of the body. Similar patterns of (i) assimilated and depurated amounts of Cu, (ii) Cu body distribution, and (iii) effect on isopods feeding behavior were observed regardless of whether the animals were fed with Cu NPs or soluble Cu salt spiked food. Thus, Cu ions and not Cu NPs were assimilated by the digestive gland cells. Solubilization of the Cu NPs applied to the leaves was also analyzed with chemical methods and recombinant Cu-sensing bacteria. The comparison of the in vitro data on solubilization of Cu NPs and in vivo data on Cu accumulation in the animal tissues showed that about 99% of accumulated copper ions was dissolved from ingested Cu NPs in the digestive system of isopods.

  2. Effect of divergence in phenotypic residual feed intake on methane emissions, ruminal fermentation, and apparent whole-tract digestibility of beef heifers across three contrasting diets.

    PubMed

    McDonnell, R P; Hart, K J; Boland, T M; Kelly, A K; McGee, M; Kenny, D A

    2016-03-01

    This study aimed to examine the effect of divergent phenotypic ranking for residual feed intake (RFI) on ruminal CH emissions, diet digestibility, and indices of ruminal fermentation in heifers across 3 commercially relevant diets. Twenty-eight Limousin × Friesian heifers were used and were ranked on the basis of phenotypic RFI: 14 low-RFI and 14 high-RFI animals. Ruminal CH emissions were estimated over 5 d using the SF tracer gas technique on 3 successive occasions: 1) at the end of a 6-wk period (Period 1) on grass silage (GS), 2) at the end of an 8-wk period (Period 2) at pasture, and 3) at the end of a 5-wk period (Period 3) on a 30:70 corn silage:concentrate total mixed ration (TMR). Animals were allowed ad libitum access to feed and water at all times. Individual DMI was estimated during CH measurement and rumen samples were taken at the end of each CH measurement period. Diet type affected all feed intake and CH traits measured ( < 0.01) but was unavoidably confounded with animal age/size and experimental period. Correlation coefficients between RFI and DMI were significant ( < 0.05) only when animals were fed the TMR. Daily CH correlated with DMI ( = 0.42, < 0.05) only when animals grazed pasture. Daily DMI was lower in low-RFI animals ( = 0.047) but only when expressed as grams per kilogram metabolic BW. Absolute CH emissions did not differ between RFI groups ( > 0.05), but CH yield was greatest in low-RFI heifers ( = 0.03) as a proportion of both DMI and GE intake. Interactions between the main effects were observed ( < 0.05) for CP digestibility (CPD), DM digestibility (DMD), ruminal propionate, and the acetate:propionate ratio. Low-RFI animals had greater ( < 0.05) CPD and DMD than their high-RFI contemporaries when offered GS but not the other 2 diets. Low-RFI heifers also had greater OM digestibility ( = 0.027). Additionally, low-RFI heifers had a lower concentration of propionate ( < 0.05) compared with high-RFI heifers when fed GS, resulting in a

  3. Biofuel feedstock and blended coproducts compared with deoiled corn distillers grains in feedlot diets: Effects on cattle growth performance, apparent total tract nutrient digestibility, and carcass characteristics.

    PubMed

    Opheim, T L; Campanili, P R B; Lemos, B J M; Ovinge, L A; Baggerman, J O; McCuistion, K C; Galyean, M L; Sarturi, J O; Trojan, S J

    2016-01-01

    Crossbred steers (British × Continental; = 192; initial BW 391 ± 28 kg) were used to evaluate the effects of feeding ethanol coproducts on feedlot cattle growth performance, apparent nutrient digestibility, and carcass characteristics. Steers were blocked by initial BW and assigned randomly to 1 of 6 dietary treatments within block. Treatments (replicated in 8 pens with 4 steers/pen) included 1) control, steam-flaked corn-based diet (CTL), 2) corn dried distillers grains with solubles (DGS; DRY-C), 3) deoiled corn dried DGS (DRY-CLF), 4) blended 50/50 corn/sorghum dried DGS (DRY-C/S), 5) sorghum dried DGS (DRY-S), and 6) sorghum wet DGS (WET-S). Inclusion of DGS was 25% (DM basis). The DGS diets were isonitrogenous, CTL was formulated for 13.5% CP, and all diets were balanced for ether extract. Final shrunk BW, ADG, and DMI did not differ among CTL and DGS treatments ( ≥ 0.19). Overall G:F did not differ from CTL for DRY-C, DRY-CLF, or WET-S ( ≥ 0.12); however, G:F was 9.6% less for DRY-S compared with CTL ( < 0.01) and tended ( = 0.09) to be less for DRY-C/S than CTL. For grain source, ADG and G:F were less for DRY-S vs. DRY-C ( < 0.05), but blending DRY-C/S tended ( = 0.07) to increase ADG and increased ( = 0.05) carcass-adjusted G:F vs. DRY-S. For WET-S, final BW and ADG were greater ( < 0.05), and G:F tended ( = 0.06) to be greater than for DRY-S. There was no difference in ADG, DMI, or G:F of steers fed DRY-C vs. DRY-CLF ( ≥ 0.35). Apparent DM and OM digestibility did not differ for CTL, DRY-C, DRY-CLF, and WET-S ( ≥ 0.30) but were lower for DRY-C/S and DRY-S ( < 0.05). Nutrient digestibility was lower for DRY-S vs. DRY-C ( < 0.01), but apparent digestibility of OM, DM, NDF, ADF, CP, ether extract, and starch were increased ( < 0.01) for DRY-C/S vs. DRY-S. Although starch digestibility did not differ between DRY-S and WET-S ( 0.18), digestibility of other measured nutrients was greater for WET-S vs. DRY-S ( < 0.01). Ether extract digestibility was

  4. Ontogeny and distribution of cholecystokinin-immuno reactive cells in the digestive tract of sharpsnout sea bream, Diplodus puntazzo (Cetti, 1777), during larval development.

    PubMed

    Micale, Valeria; Levanti, Maria Beatrice; Germanà, Antonino; Guerrera, Maria Cristina; Kurokawa, Tadahide; Muglia, Ugo

    2010-10-01

    The appearance and regional distribution of cholecystokinin-immuno reactive cells (CCK-IR) in the developing gut of larval Diplodus puntazzo were studied by means of immunohistochemistry, with the aim of understanding the role of this peptide hormone in the acquisition of digestive capacity. Immunohistochemical reaction showed CCK-IR cells from 10 days after hatching (DAH), near the pyloric sphincter and past the first bend in the midgut, as well as in the hindgut. At 25 DAH CCK-IR cells were scattered throughout the midgut, as well as in the hindgut. Since gastric glands appeared at 30 DAH, CCK-IR cells were most abundant in the anterior midgut, near and including the pyloric caeca, and just afore the ileo-rectal sphincter in the posterior midgut, as well as in the hindgut. In older larvae (39 DAH), CCK-IR cells were mainly distributed in the anterior midgut, including the pyloric caeca, as well as in the hindgut. No CCK-IR cells were detected in the foregut at any stage. The distribution pattern of CCK-IR cells differed from other species which also possess a rotated gut as D. puntazzo. In fact, although cells were abundant in regions where the ingested food is retained, so that they can be stimulated to modulating the release of digestive enzymes, a large number of cells occurred also in the hindgut. PMID:20619264

  5. Determination of the adequate dose of garlic diallyl disulfide and diallyl trisulfide for effecting changes in growth performance, total-tract nutrient and energy digestibility, ileal characteristics, and serum immune parameters in broiler chickens.

    PubMed

    Horn, Nathan L; Ruch, Frank; Miller, Guy; Ajuwon, Kolapo M; Adeola, Olayiwola

    2016-10-01

    The objective of the current experiment was to determine the adequate dose and impact of graded concentrations of garlic diallyl disulfide (DADS) and diallyl trisulfide (DATS) on growth performance, total-tract nutrient and energy digestibility, serum immune parameters, and ileal morphology in broiler chickens. At 28-d post-hatch, male broiler chickens were allotted on the basis of initial body weight (1.34 ± 0.106 kg) in a randomized complete block desing ( RCBD: ) to one of six treatments that consisted of an oral gavage of 0, 0.45, 0.90, 1.80, 3.6, or 7.2 mg of DADS + DATS per kg bodyweight (BW) with 8 replicate cages per treatment and 4 birds per cage. The DADS + DATS was administered to birds by daily oral gavage for a period of 6 d. Growth performance was recorded and excreta were collected for analysis of DM, nitrogen ( N: ), and energy ( E: ) digestibility and on the last day of the experiment, the median bird in each cage was euthanized and the mid ileum was excised for morphological and gene expression measurements and blood was collected for serum natural antibody and complement assays. Body weight gain and villus height were linearly increased (P < 0.01) with oral gavage of DADS + DATS. There was a quadratic effect (P < 0.01) of the oral gavage on digestibility of DM, N, and E that corresponded to an average broken-line regression-derived adequate dose of 1.16 mg DADS + DATS per kg BW. Supplementation of DADS + DATS by oral gavage had no impact on gene expression markers although there was a tendency for an increase (P = 0.10) in serum natural antibody activity due to treatment. Results from the current study indicate that supplementation of a gavage containing DADS + DATS improves BW gain, ileal morphology, and digestibility of DM, N, and E and may affect serum immune parameters in broiler chickens. The average broken-line regression-derived adequate dose to optimize BW gain and villus height response was 2.51 mg DADS + DATS per kg BW.

  6. Determination of the adequate dose of garlic diallyl disulfide and diallyl trisulfide for effecting changes in growth performance, total-tract nutrient and energy digestibility, ileal characteristics, and serum immune parameters in broiler chickens.

    PubMed

    Horn, Nathan L; Ruch, Frank; Miller, Guy; Ajuwon, Kolapo M; Adeola, Olayiwola

    2016-10-01

    The objective of the current experiment was to determine the adequate dose and impact of graded concentrations of garlic diallyl disulfide (DADS) and diallyl trisulfide (DATS) on growth performance, total-tract nutrient and energy digestibility, serum immune parameters, and ileal morphology in broiler chickens. At 28-d post-hatch, male broiler chickens were allotted on the basis of initial body weight (1.34 ± 0.106 kg) in a randomized complete block desing ( RCBD: ) to one of six treatments that consisted of an oral gavage of 0, 0.45, 0.90, 1.80, 3.6, or 7.2 mg of DADS + DATS per kg bodyweight (BW) with 8 replicate cages per treatment and 4 birds per cage. The DADS + DATS was administered to birds by daily oral gavage for a period of 6 d. Growth performance was recorded and excreta were collected for analysis of DM, nitrogen ( N: ), and energy ( E: ) digestibility and on the last day of the experiment, the median bird in each cage was euthanized and the mid ileum was excised for morphological and gene expression measurements and blood was collected for serum natural antibody and complement assays. Body weight gain and villus height were linearly increased (P < 0.01) with oral gavage of DADS + DATS. There was a quadratic effect (P < 0.01) of the oral gavage on digestibility of DM, N, and E that corresponded to an average broken-line regression-derived adequate dose of 1.16 mg DADS + DATS per kg BW. Supplementation of DADS + DATS by oral gavage had no impact on gene expression markers although there was a tendency for an increase (P = 0.10) in serum natural antibody activity due to treatment. Results from the current study indicate that supplementation of a gavage containing DADS + DATS improves BW gain, ileal morphology, and digestibility of DM, N, and E and may affect serum immune parameters in broiler chickens. The average broken-line regression-derived adequate dose to optimize BW gain and villus height response was 2.51 mg DADS + DATS per kg BW. PMID

  7. Aero-Engine Condition Monitoring Based on Support Vector Machine

    NASA Astrophysics Data System (ADS)

    Zhang, Chunxiao; Wang, Nan

    The maintenance and management of civil aero-engine require advanced monitor approaches to estimate aero-engine performance and health in order to increase life of aero-engine and reduce maintenance costs. In this paper, we adopted support vector machine (SVM) regression approach to monitor an aero-engine health and condition by building monitoring models of main aero-engine performance parameters(EGT, N1, N2 and FF). The accuracy of nonlinear baseline models of performance parameters is tested and the maximum relative error does not exceed ±0.3%, which meets the engineering requirements. The results show that SVM nonlinear regression is an effective method in aero-engine monitoring.

  8. Results of the AEROS satellite program: Summary

    NASA Technical Reports Server (NTRS)

    Lammerzahl, P.; Rawer, K.; Roemer, N.

    1980-01-01

    Published literature reporting aeronomic data collected on two AEROS missions is summarized. The extreme ultraviolet solar radiation and other significant parameters of the thermosphere/ionosphere were investigated. Kinetic pressure, the quantity of atomic nitrogen, and partial densities of helium, oxygen, nitrogen, argon, and atomic nitrogen were determined. The thermal electron population, superthermal energy distribution, plasma density, ion temperature, and composition according to ion types were measured. The chief energy supply in the thermosphere was calculated. Aeronomic calculations showing that variations in the parameters of the ionosphere cannot be correlated with fluctuations of extreme ultraviolet solar radiation were performed. The AEROS data were compared with data from S3-1, ISIS, and AE-C satellites. Models of the thermosphere and ionosphere were developed.

  9. Transient aero-thermal simulations for TMT

    NASA Astrophysics Data System (ADS)

    Vogiatzis, Konstantinos

    2014-08-01

    Aero-thermal simulations are an integral part of the design process for the Thirty Meter Telescope (TMT). These simulations utilize Computational Solid-Fluid Dynamics (CSFD) to estimate wind jitter and blur, dome and mirror seeing, telescope pointing error due to thermal drift, and to predict thermal effects on performance of components such as the primary mirror segments. Design guidance obtained from these simulations is provided to the Telescope, Enclosure, Facilities and Adaptive Optics groups. Computational advances allow for model enhancements and inclusion of phenomena not previously resolved, such as transient effects on wind loading and thermal seeing due to vent operation while observing or long exposure effects, with potentially different flow patterns corresponding to the beginning and end of observation. Accurate knowledge of the Observatory aero-thermal environment will result in developing reliable look-up tables for effective open loop correction of key active optics system elements, and cost efficient operation of the Observatory.

  10. AeroValve Experimental Test Data Final Report

    SciTech Connect

    Noakes, Mark W.

    2014-09-01

    This report documents the collection of experimental test data and presents performance characteristics for the AeroValve brand prototype pneumatic bidirectional solenoid valves tested at the Oak Ridge National Laboratory (ORNL) in July/August 2014 as part of a validation of AeroValve energy efficiency claims. The test stand and control programs were provided by AeroValve. All raw data and processing are included in the report attachments.

  11. Effect of feed grinding methods with and without expansion on prececal and total tract mineral digestibility as well as on interior and exterior egg quality in laying hens.

    PubMed

    Hafeez, A; Mader, A; Ruhnke, I; Männer, K; Zentek, J

    2016-01-01

    The grinding of cereals by various milling methods as well as thermal treatment of feed may influence mineral digestibility and egg quality. The present study investigated the effect of feed produced by disc mill (D) and wedge-shaped disc mill (WSD), as mash (M) or expandate (E) on apparent ileal absorption (AIA) and apparent total digestibility (ATD) of calcium, phosphorus, magnesium, zinc, manganese, copper and iron, as well as on egg quality in laying hens. A total of 192 hens (Lohmann Brown) aged 19 wk, were assigned using a randomized design with a 2 × 2 factorial arrangement. Four experimental diets were offered ad libitum. Eggs were analyzed for weight, shape index, area, shell weight per unit surface area, yolk color, air cell, blood spot, Haugh unit, albumen and yolk measures (index, weight, height, width and length), shell measures (surface area, stability, density, thickness and membrane weight), as well as percent contents of albumen, yolk, shell, and shell membrane. The ATD for phosphorus, manganese, and copper was higher in WSD compared with D treatment (P = 0.028, P = 0.028 and P = 0.016, respectively). The interaction between milling methods and thermal treatment influenced ATD of copper (P = 0.033), which was higher in WSD+M group (41.0 ± 20.2) compared with D+E group (-3.21 ± 25.1), whereas no differences were observed for D+M (1.90 ± 37.8) and WSD+E (8.02 ± 36.2) groups. Egg stability tended to be higher in E compared with M treatment (P = 0.055). Albumen weight, percentage albumen weight, and albumen: yolk were higher and percentage yolk weight was lower in D compared with WSD treatment (P = 0.043, P = 0.027, P = 0.024, and P = 0.041, respectively). Number of blood spots was higher in E than M treatment (P = 0.053). In conclusion, use of a wedge-shaped disc mill resulted in higher ATD for phosphorus, manganese, and copper than use of a disc mill; however, digestibility for majority of minerals as well as egg quality parameters was

  12. Effect of feed grinding methods with and without expansion on prececal and total tract mineral digestibility as well as on interior and exterior egg quality in laying hens.

    PubMed

    Hafeez, A; Mader, A; Ruhnke, I; Männer, K; Zentek, J

    2016-01-01

    The grinding of cereals by various milling methods as well as thermal treatment of feed may influence mineral digestibility and egg quality. The present study investigated the effect of feed produced by disc mill (D) and wedge-shaped disc mill (WSD), as mash (M) or expandate (E) on apparent ileal absorption (AIA) and apparent total digestibility (ATD) of calcium, phosphorus, magnesium, zinc, manganese, copper and iron, as well as on egg quality in laying hens. A total of 192 hens (Lohmann Brown) aged 19 wk, were assigned using a randomized design with a 2 × 2 factorial arrangement. Four experimental diets were offered ad libitum. Eggs were analyzed for weight, shape index, area, shell weight per unit surface area, yolk color, air cell, blood spot, Haugh unit, albumen and yolk measures (index, weight, height, width and length), shell measures (surface area, stability, density, thickness and membrane weight), as well as percent contents of albumen, yolk, shell, and shell membrane. The ATD for phosphorus, manganese, and copper was higher in WSD compared with D treatment (P = 0.028, P = 0.028 and P = 0.016, respectively). The interaction between milling methods and thermal treatment influenced ATD of copper (P = 0.033), which was higher in WSD+M group (41.0 ± 20.2) compared with D+E group (-3.21 ± 25.1), whereas no differences were observed for D+M (1.90 ± 37.8) and WSD+E (8.02 ± 36.2) groups. Egg stability tended to be higher in E compared with M treatment (P = 0.055). Albumen weight, percentage albumen weight, and albumen: yolk were higher and percentage yolk weight was lower in D compared with WSD treatment (P = 0.043, P = 0.027, P = 0.024, and P = 0.041, respectively). Number of blood spots was higher in E than M treatment (P = 0.053). In conclusion, use of a wedge-shaped disc mill resulted in higher ATD for phosphorus, manganese, and copper than use of a disc mill; however, digestibility for majority of minerals as well as egg quality parameters was

  13. A Novel Modified Laryngeal Mask Airway Allowing Full Separation of the Digestive and Respiratory Tracts, Along With Double-Catheter Ventilation, Diagnosis, and Treatment

    PubMed Central

    Yin, Jun; Wang, Shao-Lin; Liu, Xiao-Bin

    2014-01-01

    The aim of this study was to design a novel, modified, multifunctional, and safe laryngeal mask airway (LMA). We designed an LMA with an internal catheter extending beyond the tip of the cuff. The protruding end of the internal catheter was provided with a catheter cuff, the space between the internal and external catheters was ventilatory, and the inlet ends of the 2 catheters were provided with standard connectors. We found that this design prevented reflux or aspiration of gastric content into the airway, prevented LMA dislocation, allowed ventilation through both the internal and external catheters, and allowed endoscopic examination and treatment of the gastrointestinal and respiratory tracts through both the internal and external catheters. This design overcomes the drawbacks and extends the functions of previous LMAs, offering a new approach to the development of LMAs. PMID:24670023

  14. The effects of feeding resistant starch on apparent total tract macronutrient digestibility, faecal characteristics and faecal fermentative end-products in healthy adult dogs.

    PubMed

    Beloshapka, Alison N; Alexander, Lucille G; Buff, Preston R; Swanson, Kelly S

    2014-01-01

    The benefits of whole grain consumption have been studied in human subjects, but little research exists on their effects in dogs. The objective of the present study was to test the effects of resistant starch (RS) in the diet of healthy adult dogs. Twelve adult Miniature Schnauzer dogs (eight males, four females; mean age: 3·3 (1·6) years; mean body weight: 8·4 (1·2) kg; mean body condition score: D/ideal) were randomly allotted to one of three treatment groups, which consisted of different amounts of RS supplied in a biscuit format. Dogs received either 0, 10 or 20 g biscuits per d (estimated to be 0, 2·5 or 5 g RS per d) that were fed within their daily energetic allowance. A balanced Latin square design was used, with each treatment period lasting 21 d (days 0-17 adaptation; days 18-21 fresh and total faecal collection). All dogs were fed the same diet to maintain body weight throughout the study. Dogs fed 5 g RS per d had lower (P = 0·03) fat digestibility than dogs fed 0 gRS per d, but DM, organic matter and crude protein digestibilities were not affected. Faecal fermentative end-products, including SCFA and branched-chain fatty acids, ammonia, phenols and indoles, and microbial populations were not affected. The minor changes observed in the present study suggest the RS doses provided to the dogs were too low. Further work is required to assess the dose of RS required to affect gut health. PMID:26101607

  15. The effects of feeding resistant starch on apparent total tract macronutrient digestibility, faecal characteristics and faecal fermentative end-products in healthy adult dogs.

    PubMed

    Beloshapka, Alison N; Alexander, Lucille G; Buff, Preston R; Swanson, Kelly S

    2014-01-01

    The benefits of whole grain consumption have been studied in human subjects, but little research exists on their effects in dogs. The objective of the present study was to test the effects of resistant starch (RS) in the diet of healthy adult dogs. Twelve adult Miniature Schnauzer dogs (eight males, four females; mean age: 3·3 (1·6) years; mean body weight: 8·4 (1·2) kg; mean body condition score: D/ideal) were randomly allotted to one of three treatment groups, which consisted of different amounts of RS supplied in a biscuit format. Dogs received either 0, 10 or 20 g biscuits per d (estimated to be 0, 2·5 or 5 g RS per d) that were fed within their daily energetic allowance. A balanced Latin square design was used, with each treatment period lasting 21 d (days 0-17 adaptation; days 18-21 fresh and total faecal collection). All dogs were fed the same diet to maintain body weight throughout the study. Dogs fed 5 g RS per d had lower (P = 0·03) fat digestibility than dogs fed 0 gRS per d, but DM, organic matter and crude protein digestibilities were not affected. Faecal fermentative end-products, including SCFA and branched-chain fatty acids, ammonia, phenols and indoles, and microbial populations were not affected. The minor changes observed in the present study suggest the RS doses provided to the dogs were too low. Further work is required to assess the dose of RS required to affect gut health.

  16. Digestive Diseases

    MedlinePlus

    ... cells and provide energy. This process is called digestion. Your digestive system is a series of hollow ... are also involved. They produce juices to help digestion. There are many types of digestive disorders. The ...

  17. A comparative study of the apparent total tract digestibility of carbohydrates in Icelandic and Danish warmblood horses fed two different haylages and a concentrate consisting of sugar beet pulp and black oats.

    PubMed

    Jensen, Rasmus Bovbjerg; Brokner, Christine; Knudsen, Knud Erik Bach; Tauson, Anne-Helene

    2010-10-01

    Four Icelandic (ICE) and four Danish Warmblood (DW) horses were used in a crossover study with two treatments to investigate the effect of breed and the effect of stage of maturity of haylage on the apparent total tract digestibility (ATTD) of a diet consisting of sugar beet pulp, black oats and haylage early or late cut. Fibre was analysed as crude fibre (CF), acid detergent fibre (ADF), neutral detergent fibre (NDF) and dietary fibre (DF = non-starch polysaccharides (NSP) plus lignin). In haylage all analysed fibre fractions increased with advancing stage of maturity, with the cell wall components cellulose, non-cellulosic residue, xylose and lignin causing this increase. Crude protein (CP) and sugars decreased with advancing stage of maturity. Feeding early cut haylage resulted in a significantly (p < 0.05) higher ATTD of dry matter (DM), organic matter (OM), energy, NDF, total NSP, DF and CP compared to feeding late cut haylage. There was a significantly (p < 0.05) higher ATTD of CF, DF and starch in ICE than in DW. Diet affected several faecal parameters with a significantly (p < 0.05) lower pH in faeces when horses were fed the early cut haylage. Concentrations of total short-chain fatty acids were significantly (p < 0.05) higher in faeces from horses fed early cut haylage, reflecting the higher fermentability (higher ATTD) of this diet. There was no marked effect of breed on faecal parameters. The DF analysis method gave the most appropriate differentiation of the fibre fractions and their digestibility, compared to the traditional CF, ADF and NDF analyses. A major advantage of the DF analysis is the capacity of recovering soluble fibres. The results suggested that ICE had higher ATTD of DF than DW, and this was caused by a tendency for a higher ATTD of cellulose, but further studies are required to verify that in general.

  18. Effect of the rumen ciliates Entodinium caudatum, Epidinium ecaudatum and Eudiplodinium maggii, and combinations thereof, on ruminal fermentation and total tract digestion in sheep.

    PubMed

    Zeitz, Johanna O; Amelchanka, Sergej L; Michałowski, Tadeusz; Wereszka, Krzysztof; Meile, Leo; Hartnack, Sonja; Kreuzer, Michael; Soliva, Carla R

    2012-06-01

    The quantitative importance of individual ciliate species and their interaction in the rumen is still unclear. The present study was performed to test whether there are species differences in the influence on ruminal fermentation in vivo and if combinations of ciliates act additive in that respect. Six adult wethers fed a hay-concentrate diet were defaunated, then refaunated either with Entodinium caudatum (EC), Epidinium ecaudatum (EE) or Eudiplodinium maggii (EM) alone, then progressively with all possible species combinations. Feed, faeces, urine, ruminal fluid and gas were sampled for eight days always after at least 21 days of adaptation. With a linear mixed model, accounting for the 2 x 2 x 2 full factorial study design, mean marginal effect sizes, i.e., the magnitude of change in variables as caused by the presence of each ciliate species or of combinations of them, were estimated. The apparent digestibility of organic matter and neutral detergent fibre remained unaffected. The apparent N digestibility increased by 0.054 with EM (0.716 with defaunation). Ruminal ammonia increased by 1.6, 4.0 and 8.7 mmol/l in the presence of EM, EC and EE, respectively, compared to defaunation (6.9 mmol/l). In the EM + EE combination, ruminal ammonia was lower than would have been expected from an additive effect. With EE, total short-chain fatty acids increased by 23 mmol/l (100 mmol/l with defaunation), but not when EE was combined with EM. The acetate-to-propionate ratio decreased by 0.73 units in the presence of EE (4.0 with defaunation), but only when EE was the sole ciliate species in the rumen. In the presence of any ciliate species, the 16S rDNA copies of total Bacteria and major fibrolytic species decreased to 0.52- and 0.22-fold values, respectively of that found without protozoa. Total Archaea were unaffected; however, Methanobacteriales copies increased 1.44-fold with EC. The CH4-to-CO2 ratio of ruminal gas decreased by 0.036 with EM and 0.051 with EE (0.454 with

  19. Wean-to-finish feeder space availability effects on nursery and finishing pig performance and total tract digestibility in a commercial setting when feeding dried distillers grains with solubles.

    PubMed

    Weber, E K; Stalder, K J; Patience, J F

    2015-04-01

    The study objectives were to determine nursery phase feeder space allowance effects on pig performance when double stocked and, second, to determine feeder space allowance and dried distillers grains with solubles (DDGS) inclusion level effects on pig performance and nutrient digestibility during the growing-finishing phase. This study was performed on the same group of pigs within a commercial wean-finish system. For the nursery phase, a completely randomized design was used to compare 3 feeder space allowance treatments (2.1, 2.5, and 2.9 cm/pig). A total of 3,720 pigs were randomly allotted to same-sex pens (10 feeders/treatment) housing 62 pigs/pen. Thirty 7-hole, double-sided feeders were utilized in the study. Differing linear feeder space treatments were established by blocking off sections for the nursery and grow-finish portions of this experiment. All pigs were provided equal floor space (0.26 m2/pig). In the grow-finish phase, a total of 1,860 pigs (n = 60 pens) were utilized in a 2 × 3 factorial design with 3 feeder space allowances (4.1, 4.9, or 5.7 cm/pig) and 2 dietary DDGS treatments (30% [D30] or 60% [D60]). Fecal and diet samples were collected and analyzed to estimate apparent total tract digestibility percentage (ATTD %). In the nursery portion of the trial, there was no feeder space treatment effect on ADG, ADFI, or feed efficiency (P > 0.10) from weaning to d 56 postweaning or during any weigh period. In the grow-finish portion of the trial, feeder space allowance and DDGS inclusion level did not affect ADG, ADFI, or feed efficiency (P > 0.05) from d 57 postweaning to market. Pigs fed the D30 diet had greater HCW, percent yield, and loin depth than those on the D60 diet (P < 0.05). Pigs fed the D30 treatment had greater (P < 0.05) ATTD for DM and GE for both collection periods compared with those on the D60 treatment. In summary, feeder space allowance did not impact pig performance during the nursery or grow-finish production phases

  20. Wean-to-finish feeder space availability effects on nursery and finishing pig performance and total tract digestibility in a commercial setting when feeding dried distillers grains with solubles.

    PubMed

    Weber, E K; Stalder, K J; Patience, J F

    2015-04-01

    The study objectives were to determine nursery phase feeder space allowance effects on pig performance when double stocked and, second, to determine feeder space allowance and dried distillers grains with solubles (DDGS) inclusion level effects on pig performance and nutrient digestibility during the growing-finishing phase. This study was performed on the same group of pigs within a commercial wean-finish system. For the nursery phase, a completely randomized design was used to compare 3 feeder space allowance treatments (2.1, 2.5, and 2.9 cm/pig). A total of 3,720 pigs were randomly allotted to same-sex pens (10 feeders/treatment) housing 62 pigs/pen. Thirty 7-hole, double-sided feeders were utilized in the study. Differing linear feeder space treatments were established by blocking off sections for the nursery and grow-finish portions of this experiment. All pigs were provided equal floor space (0.26 m2/pig). In the grow-finish phase, a total of 1,860 pigs (n = 60 pens) were utilized in a 2 × 3 factorial design with 3 feeder space allowances (4.1, 4.9, or 5.7 cm/pig) and 2 dietary DDGS treatments (30% [D30] or 60% [D60]). Fecal and diet samples were collected and analyzed to estimate apparent total tract digestibility percentage (ATTD %). In the nursery portion of the trial, there was no feeder space treatment effect on ADG, ADFI, or feed efficiency (P > 0.10) from weaning to d 56 postweaning or during any weigh period. In the grow-finish portion of the trial, feeder space allowance and DDGS inclusion level did not affect ADG, ADFI, or feed efficiency (P > 0.05) from d 57 postweaning to market. Pigs fed the D30 diet had greater HCW, percent yield, and loin depth than those on the D60 diet (P < 0.05). Pigs fed the D30 treatment had greater (P < 0.05) ATTD for DM and GE for both collection periods compared with those on the D60 treatment. In summary, feeder space allowance did not impact pig performance during the nursery or grow-finish production phases

  1. Absence of lactobacilli containing glycolipids with the α-galactose epitope and the enhanced fucosylation of a receptor glycolipid GA1 in the digestive tracts of immune-deficient scid mice.

    PubMed

    Iwamori, Masao; Tanaka, Kyoko; Adachi, Shigeki; Aoki, Daisuke; Nomura, Taisei

    2015-07-01

    The Lactobacillus species in the digestive tracts of immune-deficient scid mice was distinct from that in control mice, i.e. Lactobacillus murinus in scid and L. johnsonii in control mice, according to their 16S-rRNA, indicating that a symbiotic relationship between lactobacilli and a host is established under pressure from the immune system. The caecal and colonal contents rich in L. murinus of scid mice were loose with a strong sour smell, resulting in diarrhoea, and those with L. johnsonii in control mice included abundant solid materials. Lactobacillus glycolipids were revealed to be recognized by the immune system, and by TLC-immunostaining, LacTetH-DG (Galα1-6Galα1-6Galα1-2Glcα1-3'DG) of L. johnsonii was detected in the stomach, caecum and colon of control mice, but not in those of scid ones, in which fucosylation of a receptor GA1 for L. johnsonii was enhanced more than 4-fold compared with in the control mice. Thus, structural modification of receptor glycolipids was revealed to occur in the process of establishment of a symbiotic relationship between lactobacilli and a host. LacTetH-DG was also immunogenic to human, because of the presence of natural antibodies against it, and the antibody binding to it was comparable to that of blood group- and species-related glycosphingolipids.

  2. Apparent and standardized total tract digestibility by growing pigs of phosphorus in canola meal from North America and 00-rapeseed meal and 00-rapeseed expellers from Europe without and with microbial phytase.

    PubMed

    Maison, T; Liu, Y; Stein, H H

    2015-07-01

    An experiment was conducted to determine apparent total tract digestibility (ATTD) and standardized total tract digestibility (STTD) by growing pigs of P in canola meal, 00-rapeseed meal, and 00-rapeseed expellers. Canola meal and 00-rapeseed meal are the coproducts produced after the residual oil has been solvent extracted from the prepressed canola seeds and 00-rapeseeds, respectively, whereas 00-rapeseeed expellers is the coproduct from 00-rapeseeds that have been only expeller pressed. Two hundred sixteen barrows (18.0 ± 1.5 kg initial BW) were allotted to 36 diets and 6 replicate pigs per diet. Five samples of canola meal from solvent-extraction crushing plants in North America, 8 samples of 00-rapeseed meal from solvent-extraction crushing plants in Europe, and 5 samples of 00-rapeseed expellers from mechanical-press crushing plants in Europe were used in the experiment. Eighteen diets were prepared by including 40% of each source of canola meal, 00-rapeseed meal, or 00-rapeseed expellers in 1 diet. Eighteen additional diets were formulated by adding 1,500 units of microbial phytase to the diets. The only source of P in the diets was canola meal, 00-rapeseed meal, or 00-rapeseed expellers. Pigs were placed in metabolism crates that allowed for total fecal collection. Pigs were fed at 2.5 times their estimated energy requirement for maintenance. Ingredients, diets, and feces were analyzed for P, and the ATTD and STTD of each source of canola meal, 00-rapeseed meal, and 00-rapeseed expellers were calculated. A value for endogenous P loss of 190 mg/kg DMI was used to calculate the STTD of P. Results indicated that the ATTD and STTD of P for canola meal were not different from values obtained in 00-rapeseed meal, and the ATTD and STTD of P in 00-rapeseed meal were not different from values for 00-rapeseed expellers. The ATTD and STTD of P increased (P < 0.001) from 44.99 and 48.82% to 64.08 and 67.97% for canola meal, from 46.77 and 50.36% to 63.53 and 67

  3. National aero-space plane: Flight mechanics

    NASA Technical Reports Server (NTRS)

    Mciver, Duncan E.; Morrell, Frederick R.

    1990-01-01

    The current status and plans of the U.S. National Aero-Space Plane (NASP) program are reviewed. The goal of the program is to develop technology for single stage, hypersonic vehicles which use airbreathing propulsion to fly directly to orbit. The program features an X-30 flight research vehicle to explore altitude-speed regimes not amenable to ground testing. The decision to build the X-30 is now scheduled for 1993, with the first flight in the late 1990's. The flight mechanics, controls, flight management, and flight test considerations for the X-30 are discussed.

  4. Aero-optics overview. [laser applications

    NASA Technical Reports Server (NTRS)

    Gilbert, K. G.

    1980-01-01

    Various aero-optical phenomena are discussed with reference to their effect on airborne high energy lasers. Major emphasis is placed on: compressibility effects induced in the surrounding flow field; viscous effects which manifests themselves as aircraft boundary layers or shear layers; inviscid flow fields surrounding the aircraft due to airflow around protuberance such as laser turret assemblies; and shocks, established whenever local flow exceeds Mach one. The significant physical parameters affecting the interaction of a laser beam with a turbulent boundary layer are also described.

  5. Feed form and energy concentration of the diet affect growth performance and digestive tract traits of brown-egg laying pullets from hatching to 17 weeks of age.

    PubMed

    Saldaña, B; Guzmán, P; Cámara, L; García, J; Mateos, G G

    2015-08-01

    The influence of feed form and energy concentration of the diet on growth performance and the development of the gastrointestinal tract (GIT) was studied in brown-egg laying pullets. Diets formed a 2 x 5 factorial with 2 feed forms (mash vs. crumbles) and 5 levels of energy differing in 50 kcal AMEn/kg. For the entire study (0 to 17 wk of age) feeding crumbles increased ADFI (52.9 vs. 49.7 g; P < 0.001) and ADG (12.7 vs. 11.6 g; P < 0.001) and improved feed conversion ratio (FCR; 4.18 vs. 4.27; P < 0.001). An increase in the energy content of the diet decreased ADFI linearly (P < 0.001) and improved FCR quadratically (P < 0.01) but energy intake (kcal AMEn/d) was not affected. BW uniformity was higher (P < 0.05) in pullets fed crumbles than in those fed mash but was not affected (P > 0.05) by energy content of the diet. At 5, 10, and 17 wk of age, the relative weight (RW, % BW) of the GIT and the gizzard, and gizzard digesta content were lower (P < 0.05 to P < 0.001) and gizzard pH was higher (P < 0.05 to P < 0.001) in pullets fed crumbles than in pullets fed mash. Energy concentration of the diet did not affect any of the GIT variables studied. In summary, feeding crumbles improved pullet performance and reduced the RW of the GIT and gizzard, and increased gizzard pH at all ages. An increase in the energy content of the diet improved FCR from 0 to 17 wk of age. The use of crumbles and the increase in the AMEn content of the diet might be used adventageously when the objetive is to increase the BW of the pullets. However, crumbles affected the development and weight of the organs of the GIT, which might have negative effects on feed intake and egg production at the beginning of the egg laying cycle.

  6. Inclusion of fiber in diets for brown-egg laying pullets: Effects on growth performance and digestive tract traits from hatching to 17 weeks of age.

    PubMed

    Guzmán, P; Saldaña, B; Kimiaeitalab, M V; García, J; Mateos, G G

    2015-11-01

    We investigated the effects of fiber inclusion in the diet on growth performance and digestive traits in pullets from hatching to 17 wk of age. The control diets of the 3 feeding periods (0 to 5 wk, 5 to 10 wk, and 10 to 17 wk) were based on corn and soybean meal and did not include any additional fiber source. The experimental diets included 2 or 4% of cereal straw or sugar beet pulp (SBP) at the expense (wt:wt) of the control diet. From 0 to 5 wk of age, fiber inclusion did not affect pullet performance. From hatch to 17 wk of age, the inclusion of straw had little effect on pullet performance but the inclusion of 4% SBP reduced (ADG) (P < 0.05) and reduced feed conversion ratio (FCR; P < 0.001). Pullets fed straw had greater ADG (P < 0.05) and better energy conversion ratio (P < 0.01) than pullets fed SBP. An increase in fiber from 2 to 4% reduced FCR (P < 0.05). Body weight uniformity was not affected by diet. Fiber inclusion increased the relative weight (% BW) of the gizzard at 5 wk (P = 0.056) and 10 wk (P < 0.01) of age, but no differences were detected between fiber sources. At same ages, the relative length (cm/kg BW) of the pullets (P = 0.058 and P < 0.01, respectively) and tarsus (P = 0.079 and P < 0.05, respectively) was higher in pullets fed SBP than in pullets fed straw. Fiber inclusion, however, did not affect any of these traits at 17 wk of age. In summary, the inclusion of 2% straw at the expense (wt:wt) of the whole diet did not affect pullet performance at 17 wk of age. An increase in the level of straw from 2 to 4% reduced FCR but did not affect ADG. The inclusion of SBP, however, reduced pullet growth, with effects being more pronounced at the higher level. PMID:26500272

  7. Inclusion of fiber in diets for brown-egg laying pullets: Effects on growth performance and digestive tract traits from hatching to 17 weeks of age.

    PubMed

    Guzmán, P; Saldaña, B; Kimiaeitalab, M V; García, J; Mateos, G G

    2015-11-01

    We investigated the effects of fiber inclusion in the diet on growth performance and digestive traits in pullets from hatching to 17 wk of age. The control diets of the 3 feeding periods (0 to 5 wk, 5 to 10 wk, and 10 to 17 wk) were based on corn and soybean meal and did not include any additional fiber source. The experimental diets included 2 or 4% of cereal straw or sugar beet pulp (SBP) at the expense (wt:wt) of the control diet. From 0 to 5 wk of age, fiber inclusion did not affect pullet performance. From hatch to 17 wk of age, the inclusion of straw had little effect on pullet performance but the inclusion of 4% SBP reduced (ADG) (P < 0.05) and reduced feed conversion ratio (FCR; P < 0.001). Pullets fed straw had greater ADG (P < 0.05) and better energy conversion ratio (P < 0.01) than pullets fed SBP. An increase in fiber from 2 to 4% reduced FCR (P < 0.05). Body weight uniformity was not affected by diet. Fiber inclusion increased the relative weight (% BW) of the gizzard at 5 wk (P = 0.056) and 10 wk (P < 0.01) of age, but no differences were detected between fiber sources. At same ages, the relative length (cm/kg BW) of the pullets (P = 0.058 and P < 0.01, respectively) and tarsus (P = 0.079 and P < 0.05, respectively) was higher in pullets fed SBP than in pullets fed straw. Fiber inclusion, however, did not affect any of these traits at 17 wk of age. In summary, the inclusion of 2% straw at the expense (wt:wt) of the whole diet did not affect pullet performance at 17 wk of age. An increase in the level of straw from 2 to 4% reduced FCR but did not affect ADG. The inclusion of SBP, however, reduced pullet growth, with effects being more pronounced at the higher level.

  8. Dried skim milk as a replacement for soybean meal in growing-finishing diets: effects on growth performance, apparent total-tract nitrogen digestibility, urinary and fecal nitrogen excretion, and carcass traits in pigs.

    PubMed

    Yen, J T; Wells, J E; Miller, D N

    2004-11-01

    intake (P = 0.33) and the daily output of urinary urea (P = 0.88), urinary N (P = 0.97), fecal N (P = 0.69), and total manure (P = 0.62), as well as apparent total-tract N digestibility (P = 0.84) and N retention (P = 0.84). It is concluded that growing-finishing pigs fed diets containing 10% dried skim milk would have growth performance, carcass traits, and N digestibility and use similar to those fed typical corn-soybean meal diets.

  9. Effect of urea inclusion in diets containing corn dried distillers grains on feedlot cattle performance, carcass characteristics, ruminal fermentation, total tract digestibility, and purine derivatives-to-creatinine index.

    PubMed

    Ceconi, I; Ruiz-Moreno, M J; DiLorenzo, N; DiCostanzo, A; Crawford, G I

    2015-01-01

    Increased availability of rapidly fermentable carbohydrates and a great proportion of corn-derived CP in the diet may result in a degradable intake protein (DIP) deficit. Therefore, ruminal DIP deficit may result from high dietary inclusion of processed corn grain and small to moderate inclusion of corn distillers grains (DG). Two experiments were conducted to evaluate the effect of increasing dietary DIP concentration through the inclusion of urea on feedlot cattle performance, carcass characteristics, ruminal fermentation, total tract digestibility, and purine derivatives-to-creatinine (PDC) index. In Exp. 1, 42 steers (428 ± 5 kg initial BW) were assigned randomly to 1 of 3 diets containing (DM basis) 0 (control [CON]), 0.4 (low urea [LU]), or 0.6% urea (high urea [HU]) to provide 6.4, 7.5, or 8.0% dietary DIP, respectively, and 12% high-moisture corn (HMC), 20% corn dried DG with solubles (DDGS), 10% ryegrass haylage, 2.9% dry supplement, and dry-rolled corn (DRC). Steers were fed ad libitum once daily using a Calan gate system. Carcass-adjusted final BW and DMI were similar among treatments (P ≥ 0.58). Carcass-adjusted ADG was greater (P ≤ 0.04) for the HU diet compared with the LU and CON diets and was similar (P = 0.73) between the LU and CON diets. Carcass-adjusted G:F was greater (P = 0.03) for the HU diet compared with the LU diet, tended (P = 0.09) to be greater compared with the CON diet, and was similar (P = 0.61) between the LU and CON diets. Carcass characteristics were similar (P ≥ 0.34) among treatments. In Exp. 2, 4 ruminally cannulated steers (347 ± 18 kg initial BW) were randomly assigned to a replicated 2 × 2 Latin square design. Steers were fed the same CON or HU diet used in Exp. 1 ad libitum once daily. Differences in the PDC index were used as indicators of differences in microbial CP synthesis. Ruminal pH, OM intake, and starch and CP digestibility were not affected by treatment (P ≥ 0.13). Digestibility of OM and NDF and

  10. Aero-optics measurement system for the AEDC aero-optics test facility

    NASA Astrophysics Data System (ADS)

    Crosswy, F. L.; Havener, A. G.

    1991-02-01

    A fundamental problem associated with hypersonic, endoatmospheric, optically guided vehicles for interception of ballistic reentry vehicles is target image degradation caused by the complex flow field of the intercept vehicle. The image degradation mechanisms are collectively referred to as aero-optics (AO) effects. The AEDC aero-optics measurement system provides the hardware, software, techniques, and expertise for measurement of the fundamental AO effects parameters in a ground test facility. The AO measurement system is presently configured for use in AEDC Tunnel C, a continuous flow hypersonic wind tunnel. AO effects measurements are based upon image analysis, image jitter, and holographic interferometry techniques. The primary purpose of this report is to provide hardware descriptions for the imaging and holography systems and their associated data acquisition and data reduction systems. Information is also provided in the appendixes, which describe several AO measurements technology advances in various stages of development.

  11. A proposed university/industry/government cooperative aero educational program

    NASA Technical Reports Server (NTRS)

    Brodsky, R. F.

    1975-01-01

    A program is proposed to provide mutual aid between the beleaguered Aero Engineering degree-granting departments in the United States and United States industry/government. It is proposed that any accrued cost differentials be supported by the latter groups, although all programs proposed will provide true mutual assistance. The program suggested is designed to provide assured industrial experience for Aero faculty members, combat engineering obsolescence for industry engineers, provide assured summer work for Aero undergraduates, encourage industry/government input in curriculum and course planning, and funnel significant laboratory devices into the university system.

  12. An Outbreak of Clostridium difficile Ribotype 027 Associated with Length of Stay in the Intensive Care Unit and Use of Selective Decontamination of the Digestive Tract: A Case Control Study

    PubMed Central

    van Beurden, Yvette H.; Dekkers, Olaf M.; Bomers, Marije K.; Kaiser, Annie M.; van Houdt, Robin; Knetsch, Cornelis W.; Girbes, Armand R. J.; Mulder, Chris J. J.; Vandenbroucke-Grauls, Christina M. J. E.

    2016-01-01

    Background An outbreak of Clostridium difficile ribotype 027 infection (CDI) occurred at an university hospital, involving 19 departments. To determine what hospital-associated factors drove the outbreak of this particular strain we performed a case-control study. Methods Cases (n = 79), diagnosed with CDI due to C. difficile ribotype 027 were matched for age and treating medical specialty to four control patients (n = 316). Patients diagnosed with CDI due to other ribotypes were included as a second control group. A random selection of C. difficile ribotype 027 strains (n = 10) was genotyped by Whole Genome Sequencing (WGS). Findings WGS showed the outbreak was likely caused by a single strain of C. difficile (two or less single-nucleotide variants between isolates). Ninety-five percent of cases had used antibiotics, compared to 56% of controls. Previous admission to the intensive care unit (ICU) (OR: 2.4, 95% CI 1.0–5.6), longer length of stay (LOS), and recent hospital admission were associated with CDI ribotype 027. Cases were less likely to have been admitted to a ward with a known isolated CDI patient (OR: 0.2, 95% CI 0.1–0.6). Analysis of patients who stayed at the ICU (35 cases; 51 controls), indicated that the use of selective decontamination of the digestive tract (SDD) and a longer LOS in the ICU were associated with CDI risk. Interpretation In this large outbreak, any antibiotic use, including SDD use, appeared as a prerequisite for acquisition of the outbreak strain. The role of use of SDD and prolonged stay on the ICU could not be disentangled, but both factors can play a biologically plausible role in C. difficile acquisition and infection. PMID:27533048

  13. Aero-Assisted Pre-Stage for Ballistic and Aero-Assisted Launch Vehicles

    NASA Technical Reports Server (NTRS)

    Ustinov, Eugene A.

    2012-01-01

    A concept of an aero-assisted pre-stage is proposed, which enables launch of both ballistic and aero-assisted launch vehicles from conventional runways. The pre-stage can be implemented as a delta-wing with a suitable undercarriage, which is mated with the launch vehicle, so that their flight directions are coaligned. The ample wing area of the pre-stage combined with the thrust of the launch vehicle ensure prompt roll-out and take-off of the stack at airspeeds typical for a conventional jet airliner. The launch vehicle is separated from the pre-stage as soon as safe altitude is achieved, and the desired ascent trajectory is reached. Nominally, the pre-stage is non-powered. As an option, to save the propellant of the launch vehicle, the pre-stage may have its own short-burn propulsion system, whereas the propulsion system of the launch vehicle is activated at the separation point. A general non-dimensional analysis of performance of the pre-stage from roll-out to separation is carried out and applications to existing ballistic launch vehicle and hypothetical aero-assisted vehicles (spaceplanes) are considered.

  14. Generic method for aero-optic evaluations.

    PubMed

    Frumker, Eugene; Pade, Offer

    2004-06-01

    The effect of aerodynamic flow on the performance of an airborne optical system is becoming a critical issue in the development of electro-optic systems. A novel technique for aero-optic calculations that is based on commercially available software is presented. The optically relevant data from the computational fluid dynamics results are transformed into an index-of-refraction field and introduced as an input to the optical code. The data do not necessarily have to be presented in analytical form; instead it is introduced in a most general form as a discrete set of values located at a nonuniform grid of points. The modified quadratic Shepard method has been adopted for data interpolation, enabling a simple interface with virtually any software output. Several numerical simulations that demonstrate the technique are presented. PMID:15181800

  15. Generic method for aero-optic evaluations.

    PubMed

    Frumker, Eugene; Pade, Offer

    2004-06-01

    The effect of aerodynamic flow on the performance of an airborne optical system is becoming a critical issue in the development of electro-optic systems. A novel technique for aero-optic calculations that is based on commercially available software is presented. The optically relevant data from the computational fluid dynamics results are transformed into an index-of-refraction field and introduced as an input to the optical code. The data do not necessarily have to be presented in analytical form; instead it is introduced in a most general form as a discrete set of values located at a nonuniform grid of points. The modified quadratic Shepard method has been adopted for data interpolation, enabling a simple interface with virtually any software output. Several numerical simulations that demonstrate the technique are presented.

  16. The digestive system: part 2.

    PubMed

    Hendry, Charles; Farley, Alistair; McLafferty, Ella; Johnstone, Carolyn

    This article, which forms part of the life sciences series and is the second of two articles on the digestive system, explores the structure and function of the liver, gall bladder and pancreas. It is important that nurses understand how the digestive system works and identify its role in maintaining health. The gross structures of the liver, gall bladder and pancreas associated with the gastrointestinal tract are described, along with relevant physiology and pathologies.

  17. Aeronautical Mobile Airport Communications System (AeroMACS)

    NASA Technical Reports Server (NTRS)

    Budinger, James M.; Hall, Edward

    2011-01-01

    To help increase the capacity and efficiency of the nation s airports, a secure wideband wireless communications system is proposed for use on the airport surface. This paper provides an overview of the research and development process for the Aeronautical Mobile Airport Communications System (AeroMACS). AeroMACS is based on a specific commercial profile of the Institute of Electrical and Electronics Engineers (IEEE) 802.16 standard known as Wireless Worldwide Interoperability for Microwave Access or WiMAX (WiMax Forum). The paper includes background on the need for global interoperability in air/ground data communications, describes potential AeroMACS applications, addresses allocated frequency spectrum constraints, summarizes the international standardization process, and provides findings and recommendations from the world s first AeroMACS prototype implemented in Cleveland, Ohio, USA.

  18. Aero-optical jitter estimation using higher-order wavefronts

    NASA Astrophysics Data System (ADS)

    Whiteley, Matthew R.; Goorskey, David J.; Drye, Richard

    2013-07-01

    Wavefront measurements from wind tunnel or flight testing of an optical system are affected by jitter sources due to the measurement platform, system vibrations, or aero-mechanical buffeting. Depending on the nature of the testing, the wavefront jitter will be a composite of several effects, one of which is the aero-optical jitter; i.e., the wavefront tilt due to random air density fluctuations. To isolate the aero-optical jitter component from recent testing, we have developed an estimation technique that uses only higher-order wavefront measurements to determine the jitter. By analogy with work done previously with free-stream turbulence, we have developed a minimum mean-square error estimator using higher-order wavefront modes to compute the current-frame tilt components through a linear operation. The estimator is determined from computational fluid dynamics evaluation of aero-optical disturbances, but does not depend on the strength of such disturbances. Applying this technique to turret flight test data, we found aero-optical jitter to be 7.7±0.8 μrad and to scale with (ρ/ρSL)M2 (˜1 μrad in the actual test cases examined). The half-power point of the aero-optical jitter variance was found to be ˜2u∞/Dt and to roll off in temporal frequency with a power law between f and f.

  19. [Nutrition, cystic fibrosis and the digestive tract].

    PubMed

    Olveira, Gabriel; Olveira, Casilda

    2008-05-01

    The prevalence of hyponutrition in cystic fibrosis is high although it may vary according to the different studies. Detection of hyponutrition should be done by combining different methods, depending on their availability. However, the simplest and most validated criterion is to measure at each visit the weight (and height in children) in order to calculate the body mass index and categorizing hyponutrition according to absolute criteria: in adults < 18.5 kg/m(2), and in children as percentiles of the body mass index. Worsening of the nutritional status is directly related with the decrease in lung function parameters and it has been proposed as a morbidity (and even mortality) predictive factor in people with cystic fibrosis, independently of the level of pulmonary dysfunction. Exocrine pancreatic insufficiency is present is approximately 70-90% of the patients with cystic fibrosis and the genotype-phenotype correlation is high. Most of the patients with exocrine pancreatic insufficiency tolerate a high-fat diet provided that they are treated with pancreatic enzymes at appropriate doses. The prevalence of diabetes increases with age, reaching up 40% of the cases in patients older than 30 years. Clinical liver involvement is less prevalent (it approximately affects 1/3 of the patients). Other intestinal complications such as meconial ileus, gastroesophageal reflux, obstruction of the distal intestine, or fibrosing colon disease may also condition malnourishment. In patients with cystic fibrosis, a usual high-fat diet providing 120%-150% of the recommended calories is advised. If the nutritional goals are not achieved or maintained with diet modifications, artificial supplements may be added, although the recommendation for their use has not been endorsed by solid scientific evidences. The most frequently used preparations usually are polymeric or hypercaloric. The indications for enteral (through a tube, especially gastrostomy) or parenteral nutritional support are similar to those used in other pathologies. Dietary and nutritional control should be included in a multidisciplinary program allowing the improvement of the functional capacity and the quality of life and reducing, at least from a theoretical viewpoint, the morbimortality associated to malnourishment in these patients.

  20. Aero-Assisted Spacecraft Missions Using Hypersonic Waverider Aeroshells

    NASA Astrophysics Data System (ADS)

    Knittel, Jeremy

    This work examines the use of high-lift, low drag vehicles which perform orbital transfers within a planet's atmosphere to reduce propulsive requirements. For the foreseeable future, spacecraft mission design will include the objective of limiting the mass of fuel required. One means of accomplishing this is using aerodynamics as a supplemental force, with what is termed an aero-assist maneuver. Further, the use of a lifting body enables a mission designer to explore candidate trajectory types wholly unavailable to non-lifting analogs. Examples include missions to outer planets by way of an aero-gravity assist, aero-assisted plane change, aero-capture, and steady atmospheric periapsis probing missions. Engineering level models are created in order to simulate both atmospheric and extra-atmospheric space flight. Each mission is parameterized using discrete variables which control multiple areas of design. This work combines the areas of hypersonic aerodynamics, re-entry aerothermodynamics, spacecraft orbital mechanics, and vehicle shape optimization. In particular, emphasis is given to the parametric design of vehicles known as "waveriders" which are inversely designed from known shock flowfields. An entirely novel means of generating a class of waveriders known as "starbodies" is presented. A complete analysis is performed of asymmetric starbody forms and compared to a better understood parameterization, "osculating cone" waveriders. This analysis includes characterization of stability behavior, a critical discipline within hypersonic flight. It is shown that asymmetric starbodies have significant stability improvement with only a 10% reduction in the lift-to-drag ratio. By combining the optimization of both the shape of the vehicle and the trajectory it flies, much is learned about the benefit that can be expected from lifting aero-assist missions. While previous studies have conceptually proven the viability, this work provides thorough quantification of the

  1. Aero-Thermo-Dynamic Mass Analysis

    NASA Astrophysics Data System (ADS)

    Shiba, Kota; Yoshikawa, Genki

    2016-07-01

    Each gas molecule has its own molecular weight, while such a microscopic characteristic is generally inaccessible, and thus, it is measured indirectly through e.g. ionization in conventional mass analysis. Here, we present a novel approach to the direct measurement of molecular weight through a nanoarchitectonic combination of aerodynamics, thermodynamics, and mechanics, transducing microscopic events into macroscopic phenomena. It is confirmed that this approach can provide molecular weight of virtually any gas or vaporizable liquid sample in real-time without ionization. Demonstrations through analytical calculations, numerical simulations, and experiments verify the validity and versatility of the novel mass analysis realized by a simple setup with a flexible object (e.g. with a bare cantilever and even with a business card) placed in a laminar jet. Owing to its unique and simple working principle, this aero-thermo-dynamic mass analysis (AMA) can be integrated into various analytical devices, production lines, and consumer mobile platforms, opening new chapters in aerodynamics, thermodynamics, mechanics, and mass analysis.

  2. Aero-Thermo-Dynamic Mass Analysis.

    PubMed

    Shiba, Kota; Yoshikawa, Genki

    2016-07-14

    Each gas molecule has its own molecular weight, while such a microscopic characteristic is generally inaccessible, and thus, it is measured indirectly through e.g. ionization in conventional mass analysis. Here, we present a novel approach to the direct measurement of molecular weight through a nanoarchitectonic combination of aerodynamics, thermodynamics, and mechanics, transducing microscopic events into macroscopic phenomena. It is confirmed that this approach can provide molecular weight of virtually any gas or vaporizable liquid sample in real-time without ionization. Demonstrations through analytical calculations, numerical simulations, and experiments verify the validity and versatility of the novel mass analysis realized by a simple setup with a flexible object (e.g. with a bare cantilever and even with a business card) placed in a laminar jet. Owing to its unique and simple working principle, this aero-thermo-dynamic mass analysis (AMA) can be integrated into various analytical devices, production lines, and consumer mobile platforms, opening new chapters in aerodynamics, thermodynamics, mechanics, and mass analysis.

  3. Modular Aero-Propulsion System Simulation

    NASA Technical Reports Server (NTRS)

    Parker, Khary I.; Guo, Ten-Huei

    2006-01-01

    The Modular Aero-Propulsion System Simulation (MAPSS) is a graphical simulation environment designed for the development of advanced control algorithms and rapid testing of these algorithms on a generic computational model of a turbofan engine and its control system. MAPSS is a nonlinear, non-real-time simulation comprising a Component Level Model (CLM) module and a Controller-and-Actuator Dynamics (CAD) module. The CLM module simulates the dynamics of engine components at a sampling rate of 2,500 Hz. The controller submodule of the CAD module simulates a digital controller, which has a typical update rate of 50 Hz. The sampling rate for the actuators in the CAD module is the same as that of the CLM. MAPSS provides a graphical user interface that affords easy access to engine-operation, engine-health, and control parameters; is used to enter such input model parameters as power lever angle (PLA), Mach number, and altitude; and can be used to change controller and engine parameters. Output variables are selectable by the user. Output data as well as any changes to constants and other parameters can be saved and reloaded into the GUI later.

  4. Aero-Thermo-Dynamic Mass Analysis.

    PubMed

    Shiba, Kota; Yoshikawa, Genki

    2016-01-01

    Each gas molecule has its own molecular weight, while such a microscopic characteristic is generally inaccessible, and thus, it is measured indirectly through e.g. ionization in conventional mass analysis. Here, we present a novel approach to the direct measurement of molecular weight through a nanoarchitectonic combination of aerodynamics, thermodynamics, and mechanics, transducing microscopic events into macroscopic phenomena. It is confirmed that this approach can provide molecular weight of virtually any gas or vaporizable liquid sample in real-time without ionization. Demonstrations through analytical calculations, numerical simulations, and experiments verify the validity and versatility of the novel mass analysis realized by a simple setup with a flexible object (e.g. with a bare cantilever and even with a business card) placed in a laminar jet. Owing to its unique and simple working principle, this aero-thermo-dynamic mass analysis (AMA) can be integrated into various analytical devices, production lines, and consumer mobile platforms, opening new chapters in aerodynamics, thermodynamics, mechanics, and mass analysis. PMID:27412335

  5. Aero-Thermo-Dynamic Mass Analysis

    PubMed Central

    Shiba, Kota; Yoshikawa, Genki

    2016-01-01

    Each gas molecule has its own molecular weight, while such a microscopic characteristic is generally inaccessible, and thus, it is measured indirectly through e.g. ionization in conventional mass analysis. Here, we present a novel approach to the direct measurement of molecular weight through a nanoarchitectonic combination of aerodynamics, thermodynamics, and mechanics, transducing microscopic events into macroscopic phenomena. It is confirmed that this approach can provide molecular weight of virtually any gas or vaporizable liquid sample in real-time without ionization. Demonstrations through analytical calculations, numerical simulations, and experiments verify the validity and versatility of the novel mass analysis realized by a simple setup with a flexible object (e.g. with a bare cantilever and even with a business card) placed in a laminar jet. Owing to its unique and simple working principle, this aero-thermo-dynamic mass analysis (AMA) can be integrated into various analytical devices, production lines, and consumer mobile platforms, opening new chapters in aerodynamics, thermodynamics, mechanics, and mass analysis. PMID:27412335

  6. Digestive System

    MedlinePlus

    ... is about 30 feet long. continue How Digestion Works Digestion Begins in the Mouth The process of ... a noncongenital condition. Esophagitis is usually caused by gastroesophageal reflux disease (GERD) , a condition in which the esophageal ...

  7. Vibration modelling and verifications for whole aero-engine

    NASA Astrophysics Data System (ADS)

    Chen, G.

    2015-08-01

    In this study, a new rotor-ball-bearing-casing coupling dynamic model for a practical aero-engine is established. In the coupling system, the rotor and casing systems are modelled using the finite element method, support systems are modelled as lumped parameter models, nonlinear factors of ball bearings and faults are included, and four types of supports and connection models are defined to model the complex rotor-support-casing coupling system of the aero-engine. A new numerical integral method that combines the Newmark-β method and the improved Newmark-β method (Zhai method) is used to obtain the system responses. Finally, the new model is verified in three ways: (1) modal experiment based on rotor-ball bearing rig, (2) modal experiment based on rotor-ball-bearing-casing rig, and (3) fault simulations for a certain type of missile turbofan aero-engine vibration. The results show that the proposed model can not only simulate the natural vibration characteristics of the whole aero-engine but also effectively perform nonlinear dynamic simulations of a whole aero-engine with faults.

  8. Influence of altitude on aero-optic imaging deviation.

    PubMed

    Xu, Liang; Cai, Yuanli

    2011-06-20

    Aero-optic imaging deviation is a kind of aero-optic effect. It characterizes the image position displacement on an imaging plane. This paper studies the influence of altitude on aero-optic imaging deviation. The Reynolds-averaged Navier-Stokes solver provided in FLUENT was used for flow computations. The Runge-Kutta method based ray tracing was adopted for optics calculations. The orthogonal array was brought in for the experiment arrangement. Four representative suites of imaging deviations and imaging deviation slopes were obtained in the altitude range of 10-60 km. The results show that as altitude increases, the imaging deviation decreases, and the imaging deviation slope approaches zero from a negative value. PMID:21691360

  9. Aero-Structural Interaction, Analysis, and Shape Sensitivity

    NASA Technical Reports Server (NTRS)

    Newman, James C., III

    1999-01-01

    A multidisciplinary sensitivity analysis technique that has been shown to be independent of step-size selection is examined further. The accuracy of this step-size independent technique, which uses complex variables for determining sensitivity derivatives, has been previously established. The primary focus of this work is to validate the aero-structural analysis procedure currently being used. This validation consists of comparing computed and experimental data obtained for an Aeroelastic Research Wing (ARW-2). Since the aero-structural analysis procedure has the complex variable modifications already included into the software, sensitivity derivatives can automatically be computed. Other than for design purposes, sensitivity derivatives can be used for predicting the solution at nearby conditions. The use of sensitivity derivatives for predicting the aero-structural characteristics of this configuration is demonstrated.

  10. In-flight aero-optics of turrets

    NASA Astrophysics Data System (ADS)

    De Lucca, Nicholas; Gordeyev, Stanislav; Jumper, Eric

    2013-07-01

    Recent in-flight aero-optical measurements from the Airborne Aero-Optics Laboratory are provided, along with instrumentation and experimental set-up. Results of an extensive survey of the aero-optical environment at different viewing angles, for both flat-window and conformal-window turrets at different subsonic and low transonic speeds below M=0.65, are presented, compared and extensively discussed. A comparison between two turret geometries, hemisphere-on-cylinder and hemisphere only, plus the statistical analysis of wavefronts at different viewing angles, are also presented and discussed. Additionally, dynamics of a local shock appearing on the conformal-window turret at transonic Mach number are discussed.

  11. Vehicle Health Management Communications Requirements for AeroMACS

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Clements, Donna J.; Apaza, Rafael D.

    2012-01-01

    As the development of standards for the aeronautical mobile airport communications system (AeroMACS) progresses, the process of identifying and quantifying appropriate uses for the system is progressing. In addition to defining important elements of AeroMACS standards, indentifying the systems uses impacts AeroMACS bandwidth requirements. Although an initial 59 MHz spectrum allocation for AeroMACS was established in 2007, the allocation may be inadequate; studies have indicated that 100 MHz or more of spectrum may be required to support airport surface communications. Hence additional spectrum allocations have been proposed. Vehicle health management (VHM) systems, which can produce large volumes of vehicle health data, were not considered in the original bandwidth requirements analyses, and are therefore of interest in supporting proposals for additional AeroMACS spectrum. VHM systems are an emerging development in air vehicle safety, and preliminary estimates of the amount of data that will be produced and transmitted off an aircraft, both in flight and on the ground, have been prepared based on estimates of data produced by on-board vehicle health sensors and initial concepts of data processing approaches. This allowed an initial estimate of VHM data transmission requirements for the airport surface. More recently, vehicle-level systems designed to process and analyze VHM data and draw conclusions on the current state of vehicle health have been undergoing testing and evaluation. These systems make use of vehicle system data that is mostly different from VHM data considered previously for airport surface transmission, and produce processed system outputs that will be also need to be archived, thus generating additional data load for AeroMACS. This paper provides an analysis of airport surface data transmission requirements resulting from the vehicle level reasoning systems, within the context of overall VHM data requirements.

  12. Historical Analysis of Portuguese Primary School Textbooks (1920-2005) on the Topic of Digestion

    ERIC Educational Resources Information Center

    Carvalho, Graca S.; Silva, Rui; Clement, Pierre

    2007-01-01

    Our previous studies have shown that Portuguese primary school pupils and teachers have three main difficulties in the representation of the digestion process: the sequence of the digestive tract, blood absorption, and the relationship of the digestive function with other human functions. In this study we analysed the topic of digestion in 63…

  13. Overview of NASA Power Technologies for Space and Aero Applications

    NASA Technical Reports Server (NTRS)

    Beach, Raymond F.

    2014-01-01

    To achieve the ambitious goals that NASA has outlined for the next decades considerable development of power technology will be necessary. This presentation outlines the development objectives for both the space and aero applications. It further looks at the various power technologies that support these objectives and examines drivers that will be a driving force for future development.

  14. Technologies for the National Aero-Space Plane

    NASA Astrophysics Data System (ADS)

    Rausch, Vincent L.; Morris, Charles E. K., Jr.

    1992-08-01

    Technologies for SSTO and hypersonic atmospheric cruise flight being developed in the context of the National Aero-Space Plane (NASP) program are discussed. Emphasis is given to research in aerothermodynamics, propulsion, fuel technology, structures and materials, vehicle management systems, and CVD and instrumentation tools. Brief attention is also given to the X-30 vehicle and to long-term applications of NASP technologies.

  15. Influence of kiwifruit on protein digestion.

    PubMed

    Kaur, Lovedeep; Boland, Mike

    2013-01-01

    Green kiwifruit consumption has long been thought to assist in the digestion of food proteins due to the presence of the proteolytic enzyme actinidin. This chapter reviews the recent findings of both in vitro and in vivo studies on the effect of green kiwifruit (which contain the enzyme actinidin) on the gastro- and small-intestinal digestion of a range of common food proteins and protein-rich foods including milk, meat, fish, eggs, legumes, and cereal proteins. Clear evidence is provided that green kiwifruit, and the enzyme actinidin itself, can provide enhanced upper-tract digestion (particularly gastric) of a variety of food proteins, which lends support to a role for dietary kiwifruit as a digestive aid. Kiwifruit influences the digestion patterns of food proteins to varying extents. For some protein sources, digestion in the presence of green kiwifruit resulted in a substantially greater digestion of intact protein, and different peptide patterns were produced compared with those seen after digestion with mammalian digestive enzymes alone. Kiwifruit extract alone (in the absence of other digestive enzymes) has been observed to be capable of digesting some proteins present in foods, particularly those in yoghurt, cheese, fish, and raw eggs. An in vivo (pig) study including a positive control of added actinidin and a negative control where the actinidin in green kiwifruit had been inactivated showed conclusively that actinidin is responsible for the enhanced gastric hydrolysis of food proteins.

  16. [Role of microbiocenosis of the gastrointestinal tract in the nutrition of grouse].

    PubMed

    Vecherskiĭ, M V; Kuznetsova, T A; Kostina, N A; Gorlenko, M V; Golichenkov, M B; Umarov, M M; Naumova, E I

    2014-01-01

    In order to assess the role of the microbiocenosis of the digestive tract of herbivorous birds in transforming poor forage, the activity of cellulolytic enzymes in all departments of the gastrointestinal tract of the black grouse (Lyrurus tetrix) and Western capercaillie (Tetrao urogallus) was studied. The functional diversity of microbial communities of different departments was also investigated. In both species of birds, nitrogenase and cellobiohydrolase activities were discovered in the digestive tract, with the maximum observed in the cecum. PMID:25731039

  17. [Iron deficiency and digestive disorders].

    PubMed

    Cozon, G J N

    2014-11-01

    Iron deficiency anemia still remains problematic worldwide. Iron deficiency without anemia is often undiagnosed. We reviewed, in this study, symptoms and syndromes associated with iron deficiency with or without anemia: fatigue, cognitive functions, restless legs syndrome, hair loss, and chronic heart failure. Iron is absorbed through the digestive tract. Hepcidin and ferroportin are the main proteins of iron regulation. Pathogenic micro-organisms or intestinal dysbiosis are suspected to influence iron absorption.

  18. Comparative Digestive Physiology

    PubMed Central

    Karasov, William H.; Douglas, Angela E.

    2015-01-01

    In vertebrates and invertebrates, morphological and functional features of gastrointestinal (GI) tracts generally reflect food chemistry, such as content of carbohydrates, proteins, fats, and material(s) refractory to rapid digestion (e.g., cellulose). The expression of digestive enzymes and nutrient transporters approximately matches the dietary load of their respective substrates, with relatively modest excess capacity. Mechanisms explaining differences in hydrolase activity between populations and species include gene copy number variations and single-nucleotide polymorphisms. Transcriptional and posttranscriptional adjustments mediate phenotypic changes in the expression of hydrolases and transporters in response to dietary signals. Many species respond to higher food intake by flexibly increasing digestive compartment size. Fermentative processes by symbiotic microorganisms are important for cellulose degradation but are relatively slow, so animals that rely on those processes typically possess special enlarged compartment(s) to maintain a microbiota and other GI structures that slow digesta flow. The taxon richness of the gut microbiota, usually identified by 16S rRNA gene sequencing, is typically an order of magnitude greater in vertebrates than invertebrates, and the interspecific variation in microbial composition is strongly influenced by diet. Many of the nutrient transporters are orthologous across different animal phyla, though functional details may vary (e.g., glucose and amino acid transport with K+ rather than Na+ as a counter ion). Paracellular absorption is important in many birds. Natural toxins are ubiquitous in foods and may influence key features such as digesta transit, enzymatic breakdown, microbial fermentation, and absorption PMID:23720328

  19. Sensitivity Analysis for Coupled Aero-structural Systems

    NASA Technical Reports Server (NTRS)

    Giunta, Anthony A.

    1999-01-01

    A novel method has been developed for calculating gradients of aerodynamic force and moment coefficients for an aeroelastic aircraft model. This method uses the Global Sensitivity Equations (GSE) to account for the aero-structural coupling, and a reduced-order modal analysis approach to condense the coupling bandwidth between the aerodynamic and structural models. Parallel computing is applied to reduce the computational expense of the numerous high fidelity aerodynamic analyses needed for the coupled aero-structural system. Good agreement is obtained between aerodynamic force and moment gradients computed with the GSE/modal analysis approach and the same quantities computed using brute-force, computationally expensive, finite difference approximations. A comparison between the computational expense of the GSE/modal analysis method and a pure finite difference approach is presented. These results show that the GSE/modal analysis approach is the more computationally efficient technique if sensitivity analysis is to be performed for two or more aircraft design parameters.

  20. Biopsy - biliary tract

    MedlinePlus

    Cytology analysis - biliary tract; Biliary tract biopsy ... A sample for a biliary tract biopsy can be obtained in different ways. A needle biopsy can be done if you have a well-defined tumor. The biopsy site ...

  1. Structures technology applications for the National AeroSpace Plane

    NASA Technical Reports Server (NTRS)

    Little, T. E.

    1992-01-01

    The National AeroSpace Plane (NASP) presents a unique set of very complex structural problems that challenge our computational capabilities. Complex analyses are required in the conceptual design phase to achieve sufficient accuracy to address the extreme load conditions and to adequately evaluate vehicle weight. The computational capability must be available to perform these analyses in a rapid manner to accommodate the design process.

  2. Advanced selective plating with AeroNikl solutions

    NASA Astrophysics Data System (ADS)

    Smith, Gary W.

    1989-03-01

    This paper presents the latest technical data on nickel deposits on complex areas of engine components, obtained by the selective (brush) plating of nickel sulfamate solutions (AeroNikl-250, -400, and -575). Current applications for these coatings, and advancements in application technology, are described. Particular attention is given to a controlled velocity gap plating process developed for high-speed selective deposition in bores.

  3. 2005 PathfinderPlus Aero-Elastic Research Flight

    NASA Technical Reports Server (NTRS)

    Navarro, Robert

    2005-01-01

    This viewgraph presentation describes the 2005 Pathfinder along with an investigation of its aeroelastic responses. The contents include: 1) HALE Class of Vehicles; 2) Aero-elastic Research Flights Overall Objective; 3) General Arrangement; 4) Sensor Locations; 5) NASA Ramp Operations; 6) Lakebed Operations; 7) 1st Flight Data Set; 8) Tool development / data usage; 9) HALE Tool Development & Validation; 10) Building a HALE Foundation; 11) Compelling Needs Drive HALE Efforts; and 12) Team Photo

  4. Aerosol Comparisons Between Observations and Models: AeroCom and ABC

    NASA Technical Reports Server (NTRS)

    Chin, Mian; Schulz, Michael; Kinne, Stefan

    2011-01-01

    I will represent the AeroCom community to the Atmospheric Brown Cloud (ABC) workshop. I will summarize the activities and results from AeroCom Phase I activities in the past 8 years and introduce the new results and activities in the current AeroCom Phase II. We hope to coordinate some activities with the ABC community to share model output and data access for model evaluations, comparisons, and assessment.

  5. Improvement of the AeroClipper system for cyclones monitoring

    NASA Astrophysics Data System (ADS)

    Vargas, André; Philippe, Duvel Jean

    2016-07-01

    The AeroClipper developed by the French space agency (Centre National d'Études Spatiales, CNES) is a quasi-lagrangian device drifting with surface wind at about 20-30m above the ocean surface. It is a new and original device for real-time and continuous observation of air-sea surface parameters in open ocean remote regions. This device enables the sampling of the variability of surface parameters in particular under convective systems toward which it is attracted. The AeroClipper is therefore an ideal instrument to monitor Tropical Cyclones (TCs) in which they are likely to converge and provide original observations to evaluate and improve our current understanding and diagnostics of TCs as well as their representation in numerical models. In 2008, the AeroClipper demonstrates its capability to be captured by an Ocean Indian cyclone, as two models have converged, without damages, in the eye of Dora cyclone during the 2008 VASCO campaign. This paper will present the improvements of this balloon system for the international project 'the Year of Maritime Continent'.

  6. Effects of bulk density of steam-flaked corn in diets containing wet corn gluten feed on feedlot cattle performance, carcass characteristics, apparent total tract digestibility, and ruminal fermentation.

    PubMed

    Ponce, C H; Domby, E M; Anele, U Y; Schutz, J S; Gautam, K K; Galyean, M L

    2013-07-01

    The effects of varying bulk density of steam-flaked corn (SFC) in diets containing wet corn gluten feed (WCGF; Sweet Bran; Cargill Corn Milling, Blair, NE) have not been defined. In Exp. 1, yearling steers (n = 108; initial BW = 367 ± 1.18 kg) were housed in 27 pens (4 steers/pen) and received 1 of 3 different SFC bulk density treatments in a randomized complete block design. Bulk density treatments were 283, 335, or 386 g/L SFC in diets containing 25% WCGF (% of DM). Steers were fed once daily to provide ad libitum access to feed for an average of 163 d. For a 5-d period before d 70 of the experiment, DMI was measured, and fecal samples were collected from each pen for measurement of nutrient digestibility using dietary acid insoluble ash as a marker. Varying bulk densities of SFC did not affect (P ≥ 0.233) overall DMI, ADG, or G:F on a live- or carcass-adjusted basis. Dressing percent and LM area increased linearly (P ≤ 0.05) as bulk density increased, but other carcass traits were not affected by treatments. Intake of DM, OM, and CP during the 5-d digestion phase did not differ among bulk densities; however, starch intake increased linearly (P = 0.004) as bulk density of SFC increased. Digestibility of DM, OM, and CP tended (P ≤ 0.065) to decrease and starch digestibility decreased (P = 0.002) linearly as bulk density of SFC increased. In Exp. 2, a 3 × 3 Latin square design was used for collection of ruminal fluid from 3 ruminally cannulated Jersey steers adapted to the same diets used in Exp. 1. Bulk density did not affect NH3 concentrations, VFA molar proportions, ruminal fluid osmolality, and IVDMD of the diets. Total gas production increased linearly (P = 0.003) as bulk density of SFC increased from 283 to 335 g/L, but it decreased (P = 0.002) at 386 g/L. Present data suggest that bulk density can be increased up to 386 g/L in finishing diets containing 25% (DM basis) WCGF without affecting cattle performance and with limited effects on ruminal

  7. Dynamic modal analysis of transonic Airborne Aero-Optics Laboratory conformal window flight-test aero-optics

    NASA Astrophysics Data System (ADS)

    Goorskey, David J.; Drye, Richard; Whiteley, Matthew R.

    2013-07-01

    We discuss spatial-temporal characterizations of recent in-flight Airborne Aero-Optics Laboratory wavefront measurements at transonic speeds (Mach 0.65) with a conformal window turret as a function of turret pointing angle. Using both proper orthogonal decomposition and dynamic mode decomposition modal analysis methods, the flow dynamics are characterized. The conformal window wavefronts show shock formation between 85 deg and 90 deg and shear layer formation at a considerably lower turret aft pointing angle than would be expected at subsonic speeds without shock. At larger aft pointing angles, shear layer vortex roll-up dynamics dominate the aero-optical disturbances. In particular, the spatially and temporally periodic vortices grow in width and magnitude while the corresponding oscillation frequency drops with increasing look-back angle, thus maintaining a near constant vortex convection speed equal to about 0.6 times the free-stream velocity. From these results, a modified form of the aero-optics frequency scaling relation is proposed that yields a Strouhal number independent of turret look-back angle in the portion of the flow dominated by such Kelvin-Helmholtz shear layer vortices.

  8. Digestion of Nucleic Acids Starts in the Stomach

    PubMed Central

    Liu, Yu; Zhang, Yanfang; Dong, Ping; An, Ran; Xue, Changhu; Ge, Yinlin; Wei, Liangzhou; Liang, Xingguo

    2015-01-01

    The ingestion of nucleic acids (NAs) as a nutritional supplement or in genetically modified food has attracted the attention of researchers in recent years. Discussions over the fate of NAs led us to study their digestion in the stomach. Interestingly, we found that NAs are digested efficiently by human gastric juice. By performing digests with commercial, recombinant and mutant pepsin, a protein-specific enzyme, we learned that the digestion of NAs could be attributed to pepsin rather than to the acidity of the stomach. Further study showed that pepsin cleaved NAs in a moderately site-specific manner to yield 3′-phosphorylated fragments and the active site to digest NAs is probably the same as that used to digest protein. Our results rectify the misunderstandings that the digestion of NAs in the gastric tract begins in the intestine and that pepsin can only digest protein, shedding new light on NA metabolism and pepsin enzymology. PMID:26168909

  9. Digestion of Nucleic Acids Starts in the Stomach.

    PubMed

    Liu, Yu; Zhang, Yanfang; Dong, Ping; An, Ran; Xue, Changhu; Ge, Yinlin; Wei, Liangzhou; Liang, Xingguo

    2015-07-14

    The ingestion of nucleic acids (NAs) as a nutritional supplement or in genetically modified food has attracted the attention of researchers in recent years. Discussions over the fate of NAs led us to study their digestion in the stomach. Interestingly, we found that NAs are digested efficiently by human gastric juice. By performing digests with commercial, recombinant and mutant pepsin, a protein-specific enzyme, we learned that the digestion of NAs could be attributed to pepsin rather than to the acidity of the stomach. Further study showed that pepsin cleaved NAs in a moderately site-specific manner to yield 3'-phosphorylated fragments and the active site to digest NAs is probably the same as that used to digest protein. Our results rectify the misunderstandings that the digestion of NAs in the gastric tract begins in the intestine and that pepsin can only digest protein, shedding new light on NA metabolism and pepsin enzymology.

  10. A Research-Oriented Approach to Digestive Physiology To Replace Traditional Enzymatic Laboratories.

    ERIC Educational Resources Information Center

    Grabowski, Gregory M.; Holt, Jelena

    2002-01-01

    Describes a physiology laboratory designed to localize digestive enzymes within the digestive tract of cockroaches and develop a general conclusion about the similarities to mammalian digestion. This approach not only demonstrates the practicality of lecture material, but also provides a springboard for independent research opportunities.…

  11. 48 CFR 1852.235-70 - Center for AeroSpace Information.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Center for AeroSpace... SPACE ADMINISTRATION CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 1852.235-70 Center for AeroSpace Information. As prescribed in 1835.070(a), insert...

  12. 48 CFR 1852.235-70 - Center for AeroSpace Information.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Center for AeroSpace... SPACE ADMINISTRATION CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 1852.235-70 Center for AeroSpace Information. As prescribed in 1835.070(a), insert...

  13. 48 CFR 1852.235-70 - Center for AeroSpace Information.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Center for AeroSpace... SPACE ADMINISTRATION CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Texts of Provisions and Clauses 1852.235-70 Center for AeroSpace Information. As prescribed in 1835.070(a), insert...

  14. The use of a compact protable microcomputer system (EPSON HX 20) to measure on-line the contractile activity of the digestive tract from eight channels. Application to pharmacological tests.

    PubMed

    Hachet, T; Bueno, L; Fioramonti, J; Rode, C

    1986-09-01

    The chronically prepared gut with strain-gauge transducers is a useful model to evaluate the effects of drugs affecting the digestive motility in fed and fasted animals. This paper describes a rapid and reproducible on-line microcomputerized technique to evaluate continuously, 23 hr per day, the level of gut motility using a portable compact microcomputer (EPSON HX 20). The gastric, intestinal, and colonic motility indexes were automatically determined from the surface of the contractile waves from eight different sites over periods of time varying from 1 to 120 min. This system has been successfully used to investigate the motor effects of spasmolytic or antidiarrheal drugs inravenously (N-butyl-hyoscine, trospium, secoverine, and prifinium) or orally (trimebutine, loperamide) administered in conscious, fed dogs. PMID:3755780

  15. An experimental study of aero-optical aberration and dithering of supersonic mixing layer via BOS

    NASA Astrophysics Data System (ADS)

    Zhao, Yuxin; Yi, Shihe; Tian, Lifeng; He, Lin; Cheng, Zhongyu

    2010-01-01

    The optical performance of supersonic mixing layer is heavily deteriorated by the aero-optical aberration and dithering of coherent structures, but current measuring methods limit the spatiotemporal resolution in relevant studies. A high resolution whole-field aero-optical aberration and dithering measuring method based on the Background Orient Schlieren (BOS) technique was studied. The systematic structure, sensitivity and resolution of BOS are analyzed in this paper. The aero-optical aberration and dithering of streamwise structures in supersonic mixing layers were quantificationally studied with BOS. The aberration field of spanwise structures revealed the ribbon-like aberration structures, which heavily restrict the optical performance of a mixing layer. The quantifications of aero-optical aberration and dithering are very important in studying aero-optical performance of supersonic mixing layer.

  16. Optimization of Aero Engine Acceleration Control in Combat State Based on Genetic Algorithms

    NASA Astrophysics Data System (ADS)

    Li, Jie; Fan, Ding; Sreeram, Victor

    2012-03-01

    In order to drastically exploit the potential of the aero engine and improve acceleration performance in the combat state, an on-line optimized controller based on genetic algorithms is designed for an aero engine. For testing the validity of the presented control method, detailed joint simulation tests of the designed controller and the aero engine model are performed in the whole flight envelope. Simulation test results show that the presented control algorithm has characteristics of rapid convergence speed, high efficiency and can fully exploit the acceleration performance potential of the aero engine. Compared with the former controller, the designed on-line optimized controller (DOOC) can improve the security of the acceleration process and greatly enhance the aero engine thrust in the whole range of the flight envelope, the thrust increases an average of 8.1% in the randomly selected working states. The plane which adopts DOOC can acquire better fighting advantage in the combat state.

  17. Interference Analysis Status and Plans for Aeronautical Mobile Airport Communications System (AeroMACS)

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Wilson, Jeffrey D.

    2010-01-01

    Interference issues related to the operation of an aeronautical mobile airport communications system (AeroMACS) in the C-Band (specifically 5091-5150 MHz) is being investigated. The issue of primary interest is co-channel interference from AeroMACS into mobile-satellite system (MSS) feeder uplinks. The effort is focusing on establishing practical limits on AeroMACS transmissions from airports so that the threshold of interference into MSS is not exceeded. The analyses are being performed with the software package Visualyse Professional, developed by Transfinite Systems Limited. Results with omni-directional antennas and plans to extend the models to represent AeroMACS more accurately will be presented. These models should enable realistic analyses of emerging AeroMACS designs to be developed from NASA Test Bed, RTCA 223, and European results.

  18. Future NASA Power Technologies for Space and Aero Propulsion Applications

    NASA Technical Reports Server (NTRS)

    Soeder, James F.

    2015-01-01

    To achieve the ambitious goals that NASA has outlined for the next decades considerable development of power technology will be necessary. This presentation outlines the development objectives for both space and aero applications. It further looks at the various power technologies that support these objectives and examines drivers that will be a driving force for future development. Finally, the presentation examines what type of non-traditional learning areas should be emphasized in student curriculum so that the engineering needs of the third decade of the 21st Century are met.

  19. Hypersonic Interceptor Performance Evaluation Center aero-optics performance predictions

    NASA Astrophysics Data System (ADS)

    Sutton, George W.; Pond, John E.; Snow, Ronald; Hwang, Yanfang

    1993-06-01

    This paper describes the Hypersonic Interceptor Performance Evaluation Center's (HIPEC) aerooptics performance predictions capability. It includes code results for three dimensional shapes and comparisons to initial experiments. HIPEC consists of a collection of aerothermal, aerodynamic computational codes which are capable of covering the entire flight regime from subsonic to hypersonic flow and include chemical reactions and turbulence. Heat transfer to the various surfaces is calculated as an input to cooling and ablation processes. HIPEC also has aero-optics codes to determine the effect of the mean flowfield and turbulence on the tracking and imaging capability of on-board optical sensors. The paper concentrates on the latter aspects.

  20. AeroVironment technician checks a Helios solar cell panel

    NASA Technical Reports Server (NTRS)

    2000-01-01

    A technician at AeroVironment's Design Development Center in Simi Valley, California, checks a panel of silicon solar cells for conductivity and voltage. The bi-facial cells, fabricated by SunPower, Inc., of Sunnyvale, California, are among 64,000 solar cells which have been installed on the Helios Prototype solar-powered aircraft to provide power to its 14 electric motors and operating systems. Developed by AeroVironment under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project, the Helios Prototype is the forerunner of a planned fleet of slow-flying, long duration, high-altitude aircraft which can perform atmospheric science missions and serve as telecommunications relay platforms in the stratosphere. Target goals set by NASA for the giant 246-foot span flying wing include reaching and sustaining subsonic horizontal flight at 100,000 feet altitude in 2001, and sustained continuous flight for at least four days and nights above 50,000 feet altitude with the aid of a regenerative fuel cell-based energy storage system now under development in 2003.

  1. Overview of additive manufacturing activities at MTU aero engines

    NASA Astrophysics Data System (ADS)

    Bamberg, Joachim; Dusel, Karl-Heinz; Satzger, Wilhelm

    2015-03-01

    Additive Manufacturing (AM) is a promising technology to produce parts easily and effectively, just by using metallic powder or wire as starting material and a sophisticated melting process. In contrast to milling or turning technologies complex shaped and hollow parts can be built up in one step. That reduces the production costs and allows the implementation of complete new 3D designs. Therefore AM is also of great interest for aerospace and aero engine industry. MTU Aero Engines has focused its AM activities to the selective laser melting technique (SLM). This technique uses metallic powder and a laser for melting and building up the part layer by layer. It is shown which lead part was selected for AM and how the first production line was established. A special focus is set on the quality assurance of the selective laser melting process. In addition to standard non-destructive inspection techniques a new online monitoring tool was developed and integrated into the SLM machines. The basics of this technique is presented.

  2. SnapShot: Hormones of the gastrointestinal tract.

    PubMed

    Coate, Katie C; Kliewer, Steven A; Mangelsdorf, David J

    2014-12-01

    Specialized endocrine cells secrete a variety of peptide hormones all along the gastrointestinal (GI) tract, making it one of the largest endocrine organs in the body. Nutrients and developmental and neural cues trigger the secretion of gastrointestinal (GI) hormones from specialized endocrine cells along the GI tract. These hormones act in target tissues to facilitate digestion and regulate energy homeostasis. This SnapShot summarizes the production and functions of GI hormones.

  3. Improving the efficiency of feed utilization in poultry by selection. 2. Genetic parameters of excretion traits and correlations with anatomy of the gastro-intestinal tract and digestive efficiency

    PubMed Central

    2011-01-01

    Background Poultry production has been widely criticized for its negative environmental impact related to the quantity of manure produced and to its nitrogen and phosphorus content. In this study, we investigated which traits related to excretion could be used to select chickens for lower environmental pollution. The genetic parameters of several excretion traits were estimated on 630 chickens originating from 2 chicken lines divergently selected on apparent metabolisable energy corrected for zero nitrogen (AMEn) at constant body weight. The quantity of excreta relative to feed consumption (CDUDM), the nitrogen and phosphorus excreted, the nitrogen to phosphorus ratio and the water content of excreta were measured, and the consequences of such selection on performance and gastro-intestinal tract (GIT) characteristics estimated. The genetic correlations between excretion, GIT and performance traits were established. Results Heritability estimates were high for CDUDM and the nitrogen excretion rate (0.30 and 0.29, respectively). The other excretion measurements showed low to moderate heritability estimates, ranging from 0.10 for excreta water content to 0.22 for the phosphorus excretion rate. Except for the excreta water content, the CDUDM was highly correlated with the excretion traits, ranging from -0.64 to -1.00. The genetic correlations between AMEn or CDUDM and the GIT characteristics were very similar and showed that a decrease in chicken excretion involves an increase in weight of the upper part of the GIT, and a decrease in the weight of the small intestine. Conclusion In order to limit the environmental impact of chicken production, AMEn and CDUDM seem to be more suitable criteria to include in selection schemes than feed efficiency traits. PMID:21846409

  4. Miga Aero Actuator and 2D Machined Mechanical Binary Latch

    NASA Technical Reports Server (NTRS)

    Gummin, Mark A.

    2013-01-01

    Shape memory alloy (SMA) actuators provide the highest force-to-weight ratio of any known actuator. They can be designed for a wide variety of form factors from flat, thin packages, to form-matching packages for existing actuators. SMA actuators can be operated many thousands of times, so that ground testing is possible. Actuation speed can be accurately controlled from milliseconds to position and hold, and even electronic velocity-profile control is possible. SMA actuators provide a high degree of operational flexibility, and are truly smart actuators capable of being accurately controlled by onboard microprocessors across a wide range of voltages. The Miga Aero actuator is a SMA actuator designed specifically for spaceflight applications. Providing 13 mm of stroke with either 20- or 40-N output force in two different models, the Aero actuator is made from low-outgassing PEEK (polyether ether ketone) plastic, stainless steel, and nickel-titanium SMA wires. The modular actuator weighs less than 28 grams. The dorsal output attachment allows the Aero to be used in either PUSH or PULL modes by inverting the mounting orientation. The SPA1 actuator utilizes commercially available SMA actuator wire to provide 3/8-in. (approx. =.1 cm) of stroke at a force of over 28 lb (approx. = .125 N). The force is provided by a unique packaging of the single SMA wire that provides the output force of four SMA wires mechanically in parallel. The output load is shared by allowing the SMA wire to slip around the output attachment end to adjust or balance the load, preventing any individual wire segment from experiencing high loads during actuation. A built-in end limit switch prevents overheating of the SMA element following actuation when used in conjunction with the Miga Analog Driver [a simple MOSFET (metal oxide semiconductor field-effect transistor) switching circuit]. A simple 2D machined mechanical binary latch has been developed to complement the capabilities of SMA wire

  5. Impacts of dietary calcium, phytate, and nonphytate phosphorus concentrations in the presence or absence of phytase on inositol hexakisphosphate (IP6) degradation in different segments of broilers digestive tract.

    PubMed

    Li, W; Angel, R; Kim, S-W; Brady, K; Yu, S; Plumstead, P W

    2016-03-01

    A total of 1,440 straight-run Heritage 56M × fast-feathering Cobb 500F broiler birds were fed from 11 to 13 d of age to determine the impacts of calcium (Ca), phytate phosphorus (PP), nonphytate P (NPP) and phytase concentrations on the myo-inositol hexakisphosphate (IP6) flow through the different parts of gastrointestinal tract (GIT). The experiment was a 2×2×2×3 randomized block design with 2 Ca (0.7 and 1.0%), 2 PP (0.23 and 0.34%), 2 nPP (0.28 and 0.45%) and 3 phytase (0-, 500-, and 1,000-phytase unit (FTU)/kg) concentrations. The experiment was replicated twice (block) with 3 replicates per treatment (TRT) of 10 birds per block. Concentration of IP6 in crop, proventriculus (PROV) plus (+) gizzard (GIZ) and distal ileum digesta as well as the ileal IP6 disappearance was determined at 13 d of age. In crop, higher IP6 concentration was seen with increased Ca (P < 0.05). Despite the interaction between PP and phytase, higher dietary PP led to greater IP6 concentration (P < 0.05). Similar main effects of PP and phytase were also seen in Prov+Giz and ileum (P < 0.05) without interactions. Interaction between Ca and nPP on IP6 concentration was seen in Prov+Giz (P < 0.05). Decreased ileal IP6 disappearance was found at higher Ca (62.3% at 0.7% Ca vs. 57.5% at 1.0% Ca; P < 0.05). In general, adding phytase improved IP6 degradation but the degree of impact was dependent on nPP and PP (P < 0.05). In conclusion, phytase inclusion significantly reduced IP6 concentration and IP6 disappearance in distal ileum regardless of GIT segments or diet composition, but impacts of dietary Ca, nPP, and PP differed depending on GIT segment examined.

  6. Effect of level of fiber of the rearing phase diets on egg production, digestive tract traits, and body measurements of brown egg-laying hens fed diets differing in energy concentration.

    PubMed

    Guzmán, P; Saldaña, B; Bouali, O; Cámara, L; Mateos, G G

    2016-08-01

    This research studied the effects of additional fiber in the rearing phase diets on egg production, gastrointestinal tract (GIT) traits, and body measurements of brown egg-laying hens fed diets varying in energy concentration from 17 to 46 wk of age. The experiment was completely randomized with 10 treatments arranged as a 5 × 2 factorial with 5 rearing phase diets and 2 laying phase diets. During the rearing phase, treatments consisted of a control diet based on cereals and soybean meal and 4 additional diets with a combination of 2 fiber sources (cereal straw and sugar beet pulp, SBP) at 2 levels (2 and 4%). During the laying phase, diets differed in energy content (2,650 vs. 2,750 kcal AMEn/kg) but had the same amino acid content per unit of energy. The rearing diet did not affect any production trait except egg production that was lower in birds fed SBP than in birds fed straw (91.6 and 94.1%, respectively; P < 0.05). Laying hens fed the high energy diet had lower feed intake (P < 0.001), better feed conversion (P < 0.01), and greater BW gain (P < 0.05) than hens fed the low energy diet but egg production and egg weight were not affected. At 46 wk of age, none of the GIT traits was affected by previous dietary treatment. At this age, hen BW was positively related with body length (r = 0.500; P < 0.01), tarsus length (r = 0.758; P < 0.001), and body mass index (r = 0.762; P < 0.001) but no effects of type of diet on these traits were detected. In summary, the inclusion of up to 4% of a fiber source in the rearing diets did not affect GIT development of the hens but SBP reduced egg production. An increase in the energy content of the laying phase diet reduced ADFI and improved feed efficiency but did not affect any of the other traits studied.

  7. Impacts of dietary calcium, phytate, and nonphytate phosphorus concentrations in the presence or absence of phytase on inositol hexakisphosphate (IP6) degradation in different segments of broilers digestive tract

    PubMed Central

    Li, W.; Angel, R.; Kim, S.-W.; Brady, K.; Yu, S.; Plumstead, P. W.

    2016-01-01

    A total of 1,440 straight-run Heritage 56M × fast-feathering Cobb 500F broiler birds were fed from 11 to 13 d of age to determine the impacts of calcium (Ca), phytate phosphorus (PP), nonphytate P (nPP) and phytase concentrations on the myo-inositol hexakisphosphate (IP6) flow through the different parts of gastrointestinal tract (GIT). The experiment was a 2×2×2×3 randomized block design with 2 Ca (0.7 and 1.0%), 2 PP (0.23 and 0.34%), 2 nPP (0.28 and 0.45%) and 3 phytase (0-, 500-, and 1,000-phytase unit (FTU)/kg) concentrations. The experiment was replicated twice (block) with 3 replicates per treatment (Trt) of 10 birds per block. Concentration of IP6 in crop, proventriculus (Prov) plus (+) gizzard (Giz) and distal ileum digesta as well as the ileal IP6 disappearance was determined at 13 d of age. In crop, higher IP6 concentration was seen with increased Ca (P < 0.05). Despite the interaction between PP and phytase, higher dietary PP led to greater IP6 concentration (P < 0.05). Similar main effects of PP and phytase were also seen in Prov+Giz and ileum (P < 0.05) without interactions. Interaction between Ca and nPP on IP6 concentration was seen in Prov+Giz (P < 0.05). Decreased ileal IP6 disappearance was found at higher Ca (62.3% at 0.7% Ca vs. 57.5% at 1.0% Ca; P < 0.05). In general, adding phytase improved IP6 degradation but the degree of impact was dependent on nPP and PP (P < 0.05). In conclusion, phytase inclusion significantly reduced IP6 concentration and IP6 disappearance in distal ileum regardless of GIT segments or diet composition, but impacts of dietary Ca, nPP, and PP differed depending on GIT segment examined. PMID:26740131

  8. Effect of level of fiber of the rearing phase diets on egg production, digestive tract traits, and body measurements of brown egg-laying hens fed diets differing in energy concentration.

    PubMed

    Guzmán, P; Saldaña, B; Bouali, O; Cámara, L; Mateos, G G

    2016-08-01

    This research studied the effects of additional fiber in the rearing phase diets on egg production, gastrointestinal tract (GIT) traits, and body measurements of brown egg-laying hens fed diets varying in energy concentration from 17 to 46 wk of age. The experiment was completely randomized with 10 treatments arranged as a 5 × 2 factorial with 5 rearing phase diets and 2 laying phase diets. During the rearing phase, treatments consisted of a control diet based on cereals and soybean meal and 4 additional diets with a combination of 2 fiber sources (cereal straw and sugar beet pulp, SBP) at 2 levels (2 and 4%). During the laying phase, diets differed in energy content (2,650 vs. 2,750 kcal AMEn/kg) but had the same amino acid content per unit of energy. The rearing diet did not affect any production trait except egg production that was lower in birds fed SBP than in birds fed straw (91.6 and 94.1%, respectively; P < 0.05). Laying hens fed the high energy diet had lower feed intake (P < 0.001), better feed conversion (P < 0.01), and greater BW gain (P < 0.05) than hens fed the low energy diet but egg production and egg weight were not affected. At 46 wk of age, none of the GIT traits was affected by previous dietary treatment. At this age, hen BW was positively related with body length (r = 0.500; P < 0.01), tarsus length (r = 0.758; P < 0.001), and body mass index (r = 0.762; P < 0.001) but no effects of type of diet on these traits were detected. In summary, the inclusion of up to 4% of a fiber source in the rearing diets did not affect GIT development of the hens but SBP reduced egg production. An increase in the energy content of the laying phase diet reduced ADFI and improved feed efficiency but did not affect any of the other traits studied. PMID:26976899

  9. Evaluation of aero-optical distortion effects in PIV

    NASA Astrophysics Data System (ADS)

    Elsinga, G. E.; Oudheusden, B. W.; Scarano, F.

    2005-08-01

    Aero-optical distortion effects on the accuracy of particle image velocimetry (PIV) are investigated. When the illuminated particles are observed through a medium that is optically inhomogeneous due to flow compressibility, the resulting particle image pattern is subjected to deformation and blur. In relation to PIV two forms of error can be identified: position error and velocity error. In this paper a model is presented that describes these errors and particle image blur in relation to the refractive index field of the flow. In the case of 2D flows the model equations can be simplified and, furthermore, the background oriented schlieren technique (BOS) can be applied as a means to assess and correct for the optical error in PIV. The model describing the optical distortion is validated by both computer simulation and real experiments of 2D flows. Two flow features are considered: one with optical distortion normal to the velocity (shear layer) and one with optical distortion in the direction of the flow (expansion fan). Both simulation and experiments demonstrate that the major source for the velocity error is the second derivative of the refractive index in the direction of the velocity vector. The aero-optical distortion effect is less critical for shearing interfaces in comparison with compression/expansion fronts, the most critical case being represented by shock waves. Based on the results from the simulated experiments, it is concluded that for the 2D flow case the BOS method allows a measurement of the mean velocity error in PIV and can reduce it to a large extent.

  10. Aero-acoustics of Drag Generating Swirling Exhaust Flows

    NASA Technical Reports Server (NTRS)

    Shah, P. N.; Mobed, D.; Spakovszky, Z. S.; Brooks, T. F.; Humphreys, W. M. Jr.

    2007-01-01

    Aircraft on approach in high-drag and high-lift configuration create unsteady flow structures which inherently generate noise. For devices such as flaps, spoilers and the undercarriage there is a strong correlation between overall noise and drag such that, in the quest for quieter aircraft, one challenge is to generate drag at low noise levels. This paper presents a rigorous aero-acoustic assessment of a novel drag concept. The idea is that a swirling exhaust flow can yield a steady, and thus relatively quiet, streamwise vortex which is supported by a radial pressure gradient responsible for pressure drag. Flows with swirl are naturally limited by instabilities such as vortex breakdown. The paper presents a first aero-acoustic assessment of ram pressure driven swirling exhaust flows and their associated instabilities. The technical approach combines an in-depth aerodynamic analysis, plausibility arguments to qualitatively describe the nature of acoustic sources, and detailed, quantitative acoustic measurements using a medium aperture directional microphone array in combination with a previously established Deconvolution Approach for Mapping of Acoustic Sources (DAMAS). A model scale engine nacelle with stationary swirl vanes was designed and tested in the NASA Langley Quiet Flow Facility at a full-scale approach Mach number of 0.17. The analysis shows that the acoustic signature is comprised of quadrupole-type turbulent mixing noise of the swirling core flow and scattering noise from vane boundary layers and turbulent eddies of the burst vortex structure near sharp edges. The exposed edges are the nacelle and pylon trailing edge and the centerbody supporting the vanes. For the highest stable swirl angle setting a nacelle area based drag coefficient of 0.8 was achieved with a full-scale Overall Sound Pressure Level (OASPL) of about 40dBA at the ICAO approach certification point.

  11. [NADPH-diaphorase activity in digestive system of gastropod molluscs Achatina fulica and Littorina littorea].

    PubMed

    Zaĭtseva, O V; Kuznetsova, T V; Markosova, T G

    2009-01-01

    Localization and peculiarities of NO-ergic elements were studied for he first time throughout the entire length of digestive tract of the marine gastropod mollusc Achatina fulica (Prosobranchia) and the terrestrial molusc Littorina littorea (Pulmonata) by using histochemical method of detection of NADPH-diaphorase (NADPHd). NO-ergic cells and fibers were revealed in all parts of the mollusc digestive tract beginning from pharynx. An intensive NADPHd activity was found in many intraepithelial cells of the open type and in their processes in intra- and subepithelial nerve plexuses, single subepithelial neurons, granular connective tissue cells, and numerous nerve fibers among muscle elements of he digestive tract wall as well as in nerves innervating the tract. NADPHd was also present in receptor cells of he oral area and in the central A. fulica ganglia participating in innervation of the digestive tract. The digestive tract NO-ergic system ofA. fulica has a more complex organization that that of L. littorea. In the A. fulica pharynx, stomach, and midgut, directly beneath epithelium, there is revealed a complex system of glomerular structures formed by thin NADPHd-positive nerve fibers coming from the side of epithelium. More superficially under the main groups of muscle elements, small agglomerations of NADPHd-positive neurons are seen, which could be considered as primitive, non-formed microganglia. Peculiarities of distribution and a possible functional role of NO-ergic elements in the digestive tract of molluscs are discussed as compared with other invertebrate and vertebrate animals. PMID:19370997

  12. Correcting the aero-optical aberration of the supersonic mixing layer with adaptive optics: concept validation.

    PubMed

    Gao, Qiong; Jiang, Zongfu; Yi, Shihe; Xie, Wenke; Liao, Tianhe

    2012-06-10

    We describe an adaptive optics (AO) system for correcting the aero-optical aberration of the supersonic mixing layer and test its performance with numerical simulations. The AO system is based on the measurement of distributed Strehl ratios and the stochastic parallel gradient descent (SPGD) algorithm. The aero-optical aberration is computed by the direct numerical simulation of a two-dimensional supersonic mixing layer. When the SPGD algorithm is applied directly, the AO cannot give effective corrections. This paper suggests two strategies to improve the performance of the SPGD algorithm for use in aero-optics. The first one is using an iteration process keeping finite memory, and the second is based on the frozen hypothesis. With these modifications, the performance of AO is improved and the aero-optical aberration can be corrected to some noticeable extent. The possibility of experimental implementation is also discussed. PMID:22695671

  13. Aero-Thermal Calibration of the NASA Glenn Icing Research Tunnel (2012 Tests)

    NASA Technical Reports Server (NTRS)

    Pastor-Barsi, Christine; Allen, Arrington E.

    2013-01-01

    A full aero-thermal calibration of the NASA Glenn Icing Research Tunnel (IRT) was completed in 2012 following the major modifications to the facility that included replacement of the refrigeration plant and heat exchanger. The calibration test provided data used to fully document the aero-thermal flow quality in the IRT test section and to construct calibration curves for the operation of the IRT.

  14. An integrated aerodynamic/propulsion study for generic aero-space planes based on waverider concepts

    NASA Technical Reports Server (NTRS)

    Rasmussen, M. L.; Emanuel, George

    1989-01-01

    The design of a unified aero-space plane based on waverider technology is analyzed. The overall aerodynamic design and performance of an aero-space plane are discussed in terms of the forebody, scramjet, and afterbody. Other subjects considered in the study are combustion/nozzle optimization, the idealized tip-to-tail waverider model, and the two-dimensional minimum length nozzle. Charts and graphs are provided to show the results of the preliminary investigations.

  15. Considerations for Improving the Capacity and Performance of AeroMACS

    NASA Technical Reports Server (NTRS)

    Kerczewski, Robert J.; Kamali, Behnam; Apaza, Rafael D.; Wilson, Jeffrey D.; Dimond, Robert P.

    2014-01-01

    The Aeronautical Mobile Airport Communications System (AeroMACS) has progressed from concept through prototype development, testing, and standards development and is now poised for the first operational deployments at nine US airports by the Federal Aviation Administration. These initial deployments will support fixed applications. Mobile applications providing connectivity to and from aircraft and ground-based vehicles on the airport surface will occur at some point in the future. Given that many fixed applications are possible for AeroMACS, it is necessary to now consider whether the existing capacity of AeroMACS will be reached even before the mobile applications are ready to be added, since AeroMACS is constrained by both available bandwidth and transmit power limitations. This paper describes some concepts that may be applied to improve the future capacity of AeroMACS, with a particular emphasis on gains that can be derived from the addition of IEEE 802.16j multihop relays to the AeroMACS standard, where a significant analysis effort has been undertaken.

  16. Dynamic finite element model validation of an assembled aero-engine casing

    NASA Astrophysics Data System (ADS)

    Huang, Zi; Zang, Chaoping; Jiang, Yuying; Wang, Xiaowei

    2016-09-01

    Structural dynamic model updating and validation of an aero-engine casing is critical to the design and development of an aircraft engine. It helps to identify the dynamic characteristics and reduce the response of the aero-engine. The modelling and parameter identification of joint are extremely difficult and important in structural dynamic analysis of the assembled aero-engine casing. In this paper, dynamic model validation technique was applied to update and validate the finite element model of an assembled aero-engine casing. First, modal test of individual casings and the assembled casing was performed by using the traditional acceleration sensors and a hammer. The modal frequencies and mode shapes were obtained by modal analysis tools. Second, the Inverse Eigen-sensitivity Method was used to correct frequency errors and MAC values of correlated mode pairs in the individual components to obtain validated models. Last, the bolt joints of two aero-engine casings were modelled by thin layer of shell elements. The material parameters or element properties of the thin-layer contact elements were updated to obtain reliable connection parameters. The results show that the errors of natural frequencies between the validated FE model of an assembled aero-engine casing and test data are within 7%, and the MAC values of main modes are above 70%, which can verify the feasibility and effectiveness of this approach.

  17. Bile acid nuclear receptor FXR and digestive system diseases

    PubMed Central

    Ding, Lili; Yang, Li; Wang, Zhengtao; Huang, Wendong

    2015-01-01

    Bile acids (BAs) are not only digestive surfactants but also important cell signaling molecules, which stimulate several signaling pathways to regulate some important biological processes. The bile-acid-activated nuclear receptor, farnesoid X receptor (FXR), plays a pivotal role in regulating bile acid, lipid and glucose homeostasis as well as in regulating the inflammatory responses, barrier function and prevention of bacterial translocation in the intestinal tract. As expected, FXR is involved in the pathophysiology of a wide range of diseases of gastrointestinal tract, including inflammatory bowel disease, colorectal cancer and type 2 diabetes. In this review, we discuss current knowledge of the roles of FXR in physiology of the digestive system and the related diseases. Better understanding of the roles of FXR in digestive system will accelerate the development of FXR ligands/modulators for the treatment of digestive system diseases. PMID:26579439

  18. Bile acid nuclear receptor FXR and digestive system diseases.

    PubMed

    Ding, Lili; Yang, Li; Wang, Zhengtao; Huang, Wendong

    2015-03-01

    Bile acids (BAs) are not only digestive surfactants but also important cell signaling molecules, which stimulate several signaling pathways to regulate some important biological processes. The bile-acid-activated nuclear receptor, farnesoid X receptor (FXR), plays a pivotal role in regulating bile acid, lipid and glucose homeostasis as well as in regulating the inflammatory responses, barrier function and prevention of bacterial translocation in the intestinal tract. As expected, FXR is involved in the pathophysiology of a wide range of diseases of gastrointestinal tract, including inflammatory bowel disease, colorectal cancer and type 2 diabetes. In this review, we discuss current knowledge of the roles of FXR in physiology of the digestive system and the related diseases. Better understanding of the roles of FXR in digestive system will accelerate the development of FXR ligands/modulators for the treatment of digestive system diseases. PMID:26579439

  19. Congenital optic tract hypoplasia.

    PubMed

    Hatsukawa, Yoshikazu; Fujio, Takahiro; Nishikawa, Masanori; Taylor, David

    2015-08-01

    We report a case of isolated unilateral optic tract hypoplasia, described only twice previously. Bilateral optic disk hypoplasia was seen ophthalmoscopically and visual field studies showed an incongruous right homonymous hemianopia. Magnetic resonance imaging showed bilateral hypoplasia of both optic nerves and the left optic tract. Spectral domain optical coherence tomography mapping correlated well with the visual field studies. PMID:26228965

  20. Gastrointestinal tract modelling in health and disease

    PubMed Central

    Liao, Dong-Hua; Zhao, Jing-Bo; Gregersen, Hans

    2009-01-01

    The gastrointestinal (GI) tract is the system of organs within multi-cellular animals that takes in food, digests it to extract energy and nutrients, and expels the remaining waste. The various patterns of GI tract function are generated by the integrated behaviour of multiple tissues and cell types. A thorough study of the GI tract requires understanding of the interactions between cells, tissues and gastrointestinal organs in health and disease. This depends on knowledge, not only of numerous cellular ionic current mechanisms and signal transduction pathways, but also of large scale GI tissue structures and the special distribution of the nervous network. A unique way of coping with this explosion in complexity is mathematical and computational modelling; providing a computational framework for the multilevel modelling and simulation of the human gastrointestinal anatomy and physiology. The aim of this review is to describe the current status of biomechanical modelling work of the GI tract in humans and animals, which can be further used to integrate the physiological, anatomical and medical knowledge of the GI system. Such modelling will aid research and ensure that medical professionals benefit, through the provision of relevant and precise information about the patient’s condition and GI remodelling in animal disease models. It will also improve the accuracy and efficiency of medical procedures, which could result in reduced cost for diagnosis and treatment. PMID:19132766

  1. - Invited Review - Calcium Digestibility and Metabolism in Pigs*

    PubMed Central

    González-Vega, J. C.; Stein, H. H.

    2014-01-01

    Calcium (Ca) and phosphorus (P) are minerals that have important physiological functions in the body. For formulation of diets for pigs, it is necessary to consider an appropriate Ca:P ratio for an adequate absorption and utilization of both minerals. Although both minerals are important, much more research has been conducted on P digestibility than on Ca digestibility. Therefore, this review focuses on aspects that are important for the digestibility of Ca. Only values for apparent total tract digestibility (ATTD) of Ca have been reported in pigs, whereas values for both ATTD and standardized total tract digestibility (STTD) of P in feed ingredients have been reported. To be able to determine STTD values for Ca it is necessary to determine basal endogenous losses of Ca. Although most Ca is absorbed in the small intestine, there are indications that Ca may also be absorbed in the colon under some circumstances, but more research to verify the extent of Ca absorption in different parts of the intestinal tract is needed. Most P in plant ingredients is usually bound to phytate. Therefore, plant ingredients have low digestibility of P due to a lack of phytase secretion by pigs. During the last 2 decades, inclusion of microbial phytase in swine diets has improved P digestibility. However, it has been reported that a high inclusion of Ca reduces the efficacy of microbial phytase. It is possible that formation of insoluble calcium-phytate complexes, or Ca-P complexes, not only may affect the efficacy of phytase, but also the digestibility of P and Ca. Therefore, Ca, P, phytate, and phytase interactions are aspects that need to be considered in Ca digestibility studies. PMID:25049919

  2. Dynamic performance of an aero-assist spacecraft - AFE

    NASA Technical Reports Server (NTRS)

    Chang, Ho-Pen; French, Raymond A.

    1992-01-01

    Dynamic performance of the Aero-assist Flight Experiment (AFE) spacecraft was investigated using a high-fidelity 6-DOF simulation model. Baseline guidance logic, control logic, and a strapdown navigation system to be used on the AFE spacecraft are also modeled in the 6-DOF simulation. During the AFE mission, uncertainties in the environment and the spacecraft are described by an error space which includes both correlated and uncorrelated error sources. The principal error sources modeled in this study include navigation errors, initial state vector errors, atmospheric variations, aerodynamic uncertainties, center-of-gravity off-sets, and weight uncertainties. The impact of the perturbations on the spacecraft performance is investigated using Monte Carlo repetitive statistical techniques. During the Solid Rocket Motor (SRM) deorbit phase, a target flight path angle of -4.76 deg at entry interface (EI) offers very high probability of avoiding SRM casing skip-out from the atmosphere. Generally speaking, the baseline designs of the guidance, navigation, and control systems satisfy most of the science and mission requirements.

  3. Multidisciplinary Design Optimization on Conceptual Design of Aero-engine

    NASA Astrophysics Data System (ADS)

    Zhang, Xiao-bo; Wang, Zhan-xue; Zhou, Li; Liu, Zeng-wen

    2016-06-01

    In order to obtain better integrated performance of aero-engine during the conceptual design stage, multiple disciplines such as aerodynamics, structure, weight, and aircraft mission are required. Unfortunately, the couplings between these disciplines make it difficult to model or solve by conventional method. MDO (Multidisciplinary Design Optimization) methodology which can well deal with couplings of disciplines is considered to solve this coupled problem. Approximation method, optimization method, coordination method, and modeling method for MDO framework are deeply analyzed. For obtaining the more efficient MDO framework, an improved CSSO (Concurrent Subspace Optimization) strategy which is based on DOE (Design Of Experiment) and RSM (Response Surface Model) methods is proposed in this paper; and an improved DE (Differential Evolution) algorithm is recommended to solve the system-level and discipline-level optimization problems in MDO framework. The improved CSSO strategy and DE algorithm are evaluated by utilizing the numerical test problem. The result shows that the efficiency of improved methods proposed by this paper is significantly increased. The coupled problem of VCE (Variable Cycle Engine) conceptual design is solved by utilizing improved CSSO strategy, and the design parameter given by improved CSSO strategy is better than the original one. The integrated performance of VCE is significantly improved.

  4. High-order parabolic beam approximation for aero-optics

    SciTech Connect

    White, Michael D.

    2010-08-01

    The parabolic beam equations are solved using high-order compact differences for the Laplacians and Runge-Kutta integration along the beam path. The solution method is verified by comparison to analytical solutions for apertured beams and both constant and complex index of refraction. An adaptive 4th-order Runge-Kutta using an embedded 2nd-order method is presented that has demonstrated itself to be very robust. For apertured beams, the results show that the method fails to capture near aperture effects due to a violation of the paraxial approximation in that region. Initial results indicate that the problem appears to be correctable by successive approximations. A preliminary assessment of the effect of turbulent scales is undertaken using high-order Lagrangian interpolation. The results show that while high fidelity methods are necessary to accurately capture the large scale flow structure, the method may not require the same level of fidelity in sampling the density for the index of refraction. The solution is used to calculate a phase difference that is directly compared with that commonly calculated via the optical path difference. Propagation through a supersonic boundary layer shows that for longer wavelengths, the traditional method to calculate the optical path is less accurate than for shorter wavelengths. While unlikely to supplant more traditional methods for most aero-optics applications, the current method can be used to give a quantitative assessment of the other methods as well as being amenable to the addition of more physics.

  5. Commercial Modular Aero-Propulsion System Simulation 40k

    NASA Technical Reports Server (NTRS)

    Guo, Ten-Huei; Lavelle, Thomas; Litt, Jonathan; Csank, Jeffrey; May, Ryan

    2011-01-01

    The Commercial Modular Aero-Propulsion System Simulation 40k (CMAPSS40k) software package is a nonlinear dynamic simulation of a 40,000-pound (approximately equals 178-kN) thrust class commercial turbofan engine, written in the MATLAB/Simulink environment. The model has been tuned to capture the behavior of flight test data, and is capable of running at any point in the flight envelope [up to 40,000 ft (approximately equals 12,200 m) and Mach 0.8]. In addition to the open-loop engine, the simulation includes a controller whose architecture is representative of that found in industry. C-MAPSS40k fills the need for an easy-to-use, realistic, transient simulation of a medium-size commercial turbofan engine with a representative controller. It is a detailed component level model (CLM) written in the industry-standard graphical MATLAB/Simulink environment to allow for easy modification and portability. At the time of this reporting, no other such model exists in the public domain.

  6. 77 FR 33752 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-07

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Special, Emphasis Panel; Symptoms of Lower Urinary Tract Dysfunction Research Network....nih.gov . Name of Committee: National Institute of Diabetes and Digestive and Kidney Diseases...

  7. Relationships between Digestive, Circulatory, and Urinary Systems in Portuguese Primary Textbooks

    ERIC Educational Resources Information Center

    Carvalho, Graça S.; Clèment, Pierre

    2007-01-01

    In this study, 63 Portuguese primary schoolbooks (1920-2005) were analyzed. The analysis focused on text information (reference to blood absorption and association of the digestive system to other human systems) and on information from images (presence or absence of image "confusion" (when the sequence of the digestive tract is not…

  8. Energy digestibility of giant pandas on bamboo-only and on supplemented diets.

    PubMed

    Finley, Tommy G; Sikes, Robert S; Parsons, Jennifer L; Rude, Brian J; Bissell, Heidi A; Ouellette, John R

    2011-01-01

    Endangered giant pandas (Ailuropoda melanoleuca) are bears (Family Ursidae), within the order Carnivora. They specialize on an herbivorous diet of bamboo yet retain a gastrointestinal tract typical of their carnivorous ancestry. The evolutionary constraints of their digestive tract result in a low extraction efficiency from bamboo (<40% in reported studies). The goal of this study was to determine the energy digestibility of bamboo by giant pandas used in digestibility trials and through subsequent analyses with bomb calorimetry. Seven digestibility trials were conducted (three with bamboo-only diets and four with supplemental diets). Energy digestibilities ranged from 7.5-38.9% for mixed diets and 9.2-34.0% for bamboo-only diets. The bamboo-only trials summarized here represent, to our knowledge, the first empirical data available for energy digestibility on a bamboo diet for giant pandas.

  9. Spatial-temporal-covariance-based modeling, analysis, and simulation of aero-optics wavefront aberrations.

    PubMed

    Vogel, Curtis R; Tyler, Glenn A; Wittich, Donald J

    2014-07-01

    We introduce a framework for modeling, analysis, and simulation of aero-optics wavefront aberrations that is based on spatial-temporal covariance matrices extracted from wavefront sensor measurements. Within this framework, we present a quasi-homogeneous structure function to analyze nonhomogeneous, mildly anisotropic spatial random processes, and we use this structure function to show that phase aberrations arising in aero-optics are, for an important range of operating parameters, locally Kolmogorov. This strongly suggests that the d5/3 power law for adaptive optics (AO) deformable mirror fitting error, where d denotes actuator separation, holds for certain important aero-optics scenarios. This framework also allows us to compute bounds on AO servo lag error and predictive control error. In addition, it provides us with the means to accurately simulate AO systems for the mitigation of aero-effects, and it may provide insight into underlying physical processes associated with turbulent flow. The techniques introduced here are demonstrated using data obtained from the Airborne Aero-Optics Laboratory.

  10. Aero-Thermal Calibration of the NASA Glenn Icing Research Tunnel (2012 Test)

    NASA Technical Reports Server (NTRS)

    Pastor-Barsi, Christine M.; Arrington, E. Allen; VanZante, Judith Foss

    2012-01-01

    A major modification of the refrigeration plant and heat exchanger at the NASA Glenn Icing Research Tunnel (IRT) occurred in autumn of 2011. It is standard practice at NASA Glenn to perform a full aero-thermal calibration of the test section of a wind tunnel facility upon completion of major modifications. This paper will discuss the tools and techniques used to complete an aero-thermal calibration of the IRT and the results that were acquired. The goal of this test entry was to complete a flow quality survey and aero-thermal calibration measurements in the test section of the IRT. Test hardware that was used includes the 2D Resistive Temperature Detector (RTD) array, 9-ft pressure survey rake, hot wire survey rake, and the quick check survey rake. This test hardware provides a map of the velocity, Mach number, total and static pressure, total temperature, flow angle and turbulence intensity. The data acquired were then reduced to examine pressure, temperature, velocity, flow angle, and turbulence intensity. Reduced data has been evaluated to assess how the facility meets flow quality goals. No icing conditions were tested as part of the aero-thermal calibration. However, the effects of the spray bar air injections on the flow quality and aero-thermal calibration measurements were examined as part of this calibration.

  11. Observation and analysis of aero-optic effects on the ORCA laser communication system

    NASA Astrophysics Data System (ADS)

    Wayne, David T.; Phillips, Ronald L.; Andrews, Larry C.; Leclerc, Troy; Sauer, Paul

    2011-06-01

    In this paper we show evidence of aero-optic effects on the measured beacon beam as the gimbal angle of a nosemounted turret changes from 0 to 90 degrees and greater with respect to the line of flight. Data from the beacon beam was collected with a new technology 3-aperture scintillometer over a 82km to 104km air-to-ground downlink during field testing of the ORCA system in Nevada in May 2009. In this paper we present data analysis on the impact of an aero-optic boundary layer on a laser link between an aircraft and a ground-based stationary node. Particularly we look at the impact of an aero-optic boundary layer on the mean, variance, scintillation, probability density function (PDF), power spectral density (PSD), and fading of the received irradiance. We find that the most compelling argument for the presence of strong aero-optic effects comes from calculating the PSD of the received beacon intensity. We also find the cumulative effect of the aero-optic boundary layer differs depending on the transmitted beam parameters, i.e. collimated or divergent.

  12. Spatial-temporal-covariance-based modeling, analysis, and simulation of aero-optics wavefront aberrations.

    PubMed

    Vogel, Curtis R; Tyler, Glenn A; Wittich, Donald J

    2014-07-01

    We introduce a framework for modeling, analysis, and simulation of aero-optics wavefront aberrations that is based on spatial-temporal covariance matrices extracted from wavefront sensor measurements. Within this framework, we present a quasi-homogeneous structure function to analyze nonhomogeneous, mildly anisotropic spatial random processes, and we use this structure function to show that phase aberrations arising in aero-optics are, for an important range of operating parameters, locally Kolmogorov. This strongly suggests that the d5/3 power law for adaptive optics (AO) deformable mirror fitting error, where d denotes actuator separation, holds for certain important aero-optics scenarios. This framework also allows us to compute bounds on AO servo lag error and predictive control error. In addition, it provides us with the means to accurately simulate AO systems for the mitigation of aero-effects, and it may provide insight into underlying physical processes associated with turbulent flow. The techniques introduced here are demonstrated using data obtained from the Airborne Aero-Optics Laboratory. PMID:25121456

  13. Fault Diagnosis of Demountable Disk-Drum Aero-Engine Rotor Using Customized Multiwavelet Method.

    PubMed

    Chen, Jinglong; Wang, Yu; He, Zhengjia; Wang, Xiaodong

    2015-10-23

    The demountable disk-drum aero-engine rotor is an important piece of equipment that greatly impacts the safe operation of aircraft. However, assembly looseness or crack fault has led to several unscheduled breakdowns and serious accidents. Thus, condition monitoring and fault diagnosis technique are required for identifying abnormal conditions. Customized ensemble multiwavelet method for aero-engine rotor condition identification, using measured vibration data, is developed in this paper. First, customized multiwavelet basis function with strong adaptivity is constructed via symmetric multiwavelet lifting scheme. Then vibration signal is processed by customized ensemble multiwavelet transform. Next, normalized information entropy of multiwavelet decomposition coefficients is computed to directly reflect and evaluate the condition. The proposed approach is first applied to fault detection of an experimental aero-engine rotor. Finally, the proposed approach is used in an engineering application, where it successfully identified the crack fault of a demountable disk-drum aero-engine rotor. The results show that the proposed method possesses excellent performance in fault detection of aero-engine rotor. Moreover, the robustness of the multiwavelet method against noise is also tested and verified by simulation and field experiments.

  14. Fault Diagnosis of Demountable Disk-Drum Aero-Engine Rotor Using Customized Multiwavelet Method

    PubMed Central

    Chen, Jinglong; Wang, Yu; He, Zhengjia; Wang, Xiaodong

    2015-01-01

    The demountable disk-drum aero-engine rotor is an important piece of equipment that greatly impacts the safe operation of aircraft. However, assembly looseness or crack fault has led to several unscheduled breakdowns and serious accidents. Thus, condition monitoring and fault diagnosis technique are required for identifying abnormal conditions. Customized ensemble multiwavelet method for aero-engine rotor condition identification, using measured vibration data, is developed in this paper. First, customized multiwavelet basis function with strong adaptivity is constructed via symmetric multiwavelet lifting scheme. Then vibration signal is processed by customized ensemble multiwavelet transform. Next, normalized information entropy of multiwavelet decomposition coefficients is computed to directly reflect and evaluate the condition. The proposed approach is first applied to fault detection of an experimental aero-engine rotor. Finally, the proposed approach is used in an engineering application, where it successfully identified the crack fault of a demountable disk-drum aero-engine rotor. The results show that the proposed method possesses excellent performance in fault detection of aero-engine rotor. Moreover, the robustness of the multiwavelet method against noise is also tested and verified by simulation and field experiments. PMID:26512668

  15. Fault Diagnosis of Demountable Disk-Drum Aero-Engine Rotor Using Customized Multiwavelet Method.

    PubMed

    Chen, Jinglong; Wang, Yu; He, Zhengjia; Wang, Xiaodong

    2015-01-01

    The demountable disk-drum aero-engine rotor is an important piece of equipment that greatly impacts the safe operation of aircraft. However, assembly looseness or crack fault has led to several unscheduled breakdowns and serious accidents. Thus, condition monitoring and fault diagnosis technique are required for identifying abnormal conditions. Customized ensemble multiwavelet method for aero-engine rotor condition identification, using measured vibration data, is developed in this paper. First, customized multiwavelet basis function with strong adaptivity is constructed via symmetric multiwavelet lifting scheme. Then vibration signal is processed by customized ensemble multiwavelet transform. Next, normalized information entropy of multiwavelet decomposition coefficients is computed to directly reflect and evaluate the condition. The proposed approach is first applied to fault detection of an experimental aero-engine rotor. Finally, the proposed approach is used in an engineering application, where it successfully identified the crack fault of a demountable disk-drum aero-engine rotor. The results show that the proposed method possesses excellent performance in fault detection of aero-engine rotor. Moreover, the robustness of the multiwavelet method against noise is also tested and verified by simulation and field experiments. PMID:26512668

  16. Upper digestive tract trichomoniasis in mourning doves and other birds

    USGS Publications Warehouse

    Stabler, R.M.; Herman, C.M.

    1951-01-01

    This paper, while partially a review of previously published reports from North America, presents many new records on the occurrence of Trichomonas gallinae in North American columbiform birds. Evidence is presented that the .infection is present throughout most of the United States and on occasion has reached epizootic proportions in mourning doves and band-tiled pigeons in isolated areas. An extensive epizootic is reported involving several thousand eastern mourning doves in the Southeastern States during the summer of 1950. Although probably the chief means of transmission is from. parent to offspring in columbiform birds (and the occurrence of infection in nestling mourning doves demonstrates that this mode of inoculation occurs) in severe epizootics there also is undoubtedly a transmission by contamination of water or food besides, or as well as, the parent to offspring transfers. When T. gallinae is implanted in clean pigeons it becomes evident that there is a variety of strains of the organisms and that they differ considerably in virulence. Some strains may kill almost every recipient, while others, though they readily infect, never produce the slightest discomfort or pathology. Nonlethal infections produce an immunity to all strains tested. In some cases, however, when these double-strain infections are further inoculated into. clean birds, the effects of either the nonlethal or the killing strain may predominate. The mechanism by which this virulence acts in the blrds is undoubtedly an important factor in determining the morbidity or mortality that may occur in a population. The prevalence of trichomoniasis in native pigeons and doves presents many practical as well as academic problems. Ultimate application of control measures, evenon an experimental basis, must await further knowledge of many more basic facts.

  17. Diseases of the digestive tract: is prevention possible and feasible?

    PubMed

    Malagelada, Juan-R

    2011-01-01

    Prevention is and will remain a major goal of medicine and gastroenterology. Economics will have a major influence. Preventive approaches will need to prove a favorable cost-benefit ratio before they are authorized for broad implementation. Personalized medicine is just starting, but undoubtedly it will accelerate, gain relevance and become an integral part of our clinical practice. Physicians in general and gastroenterologists specifically will need to seriously contemplate retraining/refocusing to gain competence in genetic/proteomic evaluation of individuals, or risk a significant degree of obsolescence. PMID:21734393

  18. [Arterial blood supply of the digestive tract in badgers].

    PubMed

    Rahm, S; Frewein, J

    1982-01-01

    In 5 dendrohyraxes, 6 heterohyraxes, and 7 procaviae the three main visceral arteries have been studied. In all hyracoidea the Arteria coeliaca divides into the Arteria lienalis, Arteria hepatica communis, and Arteria gastrica sinistra. Occasionally the latter two arteries run together for 7-15 mm before they separate. The Arteria mesenterica cranialis gives rise to the Arteriae pancreaticoduodenales caudales, Arteriae jejunales, Arteria colica media, and Arteria colica dextra and continues as Arteria ileocolica. Some animals had an Arteria colica media accessoria which supplied the first half of the colon descendens. In all other animals the entire colon descendens was supplied by the Arteria colica sinistra which originates in the Arteria mesenterica caudalis. Branches of the Arteria rectalis cranialis extend close to the anus. PMID:7124335

  19. Magnesium absorption from the digestive tract of sheep.

    PubMed

    Care, A D; Brown, R C; Farrar, A R; Pickard, D W

    1984-07-01

    Factors affecting absorption of Mg from the ovine rumen have been studied using either a pouch constructed from part of the dorsal rumen or by an isolated washed rumen technique in vivo. Net absorption of Mg against the prevailing electrochemical gradient was observed. An increase in the K/Na ratio within the rumen led to an increase in the potential difference across the rumen wall, blood positive, and to a decrease in the net efflux of Mg from the rumen. This decrease was due to an increase in Mg influx into the rumen. The addition of ammonium chloride (30 mmol/l) to the rumen contents also led to a reduction in net Mg absorption but to no significant change in potential difference. The effects of high K/Na ratio and high ammonium ion concentration within the rumen were additive in causing decreases in net effluxes of both Mg and Na. An inverse relationship was demonstrated between the Ca concentration in the rumen and the net absorption rate of Mg. It was concluded that the efflux of Mg across the rumen wall depends at least in part on a functional system for Na transport.

  20. [Computed tomography in the diagnosis of digestive tract tumors].

    PubMed

    Babiĭ, Ia S; Momot, N V

    1998-01-01

    As many as 616 patients with malignant tumours of the alimentary canal were studied by CT tomography using different contrast mediums and methodical approaches toward identifying the site of the tumour. Based on the comparison of the results obtained from pathomorphologic findings and those from the surgical intervention, CT semiotics has been developed of tumours, criteria established to determine the depth of the tumour invasion and extra-wall spread of the tumour CT potentialities were verified in the diagnosis of metastatic involvement of regional lymph nodes and remote organs as was the role of the method in selection of a specific therapeutic alternative.

  1. 75 FR 43101 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Model PIAGGIO P-180 Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-23

    ... rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and 3. Will... fuel heater was due to chafing with an oil cooling system hose. PIAGGIO AERO INDUSTIRES (PAI) issued... system hose. Piaggio Aero Industries (PAI) issued Service Bulletin (SB) 80- 0175, which was applicable...

  2. Insights into Digestion and Absorption of Major Nutrients in Humans

    ERIC Educational Resources Information Center

    Goodman, Barbara E.

    2010-01-01

    Nutrient digestion and absorption is necessary for the survival of living organisms and has evolved into the complex and specific task of the gastrointestinal (GI) system. While most people simply assume that their GI tract will work properly to use nutrients, provide energy, and release wastes, few nonscientists know the details about how various…

  3. High-Temperature Adhesives for Thermally Stable Aero-Assist Technologies

    NASA Technical Reports Server (NTRS)

    Eberts, Kenneth; Ou, Runqing

    2013-01-01

    Aero-assist technologies are used to control the velocity of exploration vehicles (EVs) when entering Earth or other planetary atmospheres. Since entry of EVs in planetary atmospheres results in significant heating, thermally stable aero-assist technologies are required to avoid the high heating rates while maintaining low mass. Polymer adhesives are used in aero-assist structures because of the need for high flexibility and good bonding between layers of polymer films or fabrics. However, current polymer adhesives cannot withstand temperatures above 400 C. This innovation utilizes nanotechnology capabilities to address this need, leading to the development of high-temperature adhesives that exhibit high thermal conductivity in addition to increased thermal decomposition temperature. Enhanced thermal conductivity will help to dissipate heat quickly and effectively to avoid temperature rising to harmful levels. This, together with increased thermal decomposition temperature, will enable the adhesives to sustain transient high-temperature conditions.

  4. AeroMACS C-Band Interference Modeling and Simulation Results

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey

    2010-01-01

    A new C-band (5091-5150 MHz) airport communications system designated as Aeronautical Mobile Airport Communications System (AeroMACS) is being planned under the Federal Aviation Administration s NextGen program. It is necessary to establish practical limits on AeroMACS transmission power from airports so that the threshold of interference into the Mobile Satellite Service (Globalstar) feeder uplinks is not exceeded. To help provide guidelines for these limits, interference models have been created with the commercial software Visualyse Professional. In this presentation, simulation results were shown for the aggregate interference power at low earth orbit from AeroMACS transmitters at each of up to 757 airports in the United States, Canada, Mexico, and the surrounding area. Both omni-directional and sectoral antenna configurations were modeled. Effects of antenna height, beamwidth, and tilt were presented.

  5. Aero-thermal analysis of lifting body configurations in hypersonic flow

    NASA Astrophysics Data System (ADS)

    Kumar, Sachin; Mahulikar, Shripad P.

    2016-09-01

    The aero-thermal analysis of a hypersonic vehicle is of fundamental interest for designing its thermal protection system. The aero-thermal environment predictions over several critical regions of the hypothesized lifting body vehicle, including the stagnation region of the nose-cap, cylindrically swept leading edges, fuselage-upper, and fuselage-lower surfaces, are discussed. The drag (Λ=70°) and temperature (Λ=80°) minimized sweepback angles are considered in the configuration design of the two hypothesized lifting body shape hypersonic vehicles. The main aim of the present study is to analyze and compare the aero-thermal characteristics of these two lifting body configurations at same heat capacity. Accordingly, a Computational Fluid Dynamics simulation has been carried out at Mach number (M∞=7), H=35 km altitude with zero Angle of Attack. Finally, the material selection for thermal protection system based on these predictions and current methodology is described.

  6. Frequency-domain Model Matching PID Controller Design for Aero-engine

    NASA Astrophysics Data System (ADS)

    Liu, Nan; Huang, Jinquan; Lu, Feng

    2014-12-01

    The nonlinear model of aero-engine was linearized at multiple operation points by using frequency response method. The validation results indicate high accuracy of static and dynamic characteristics of the linear models. The improved PID tuning method of frequency-domain model matching was proposed with the system stability condition considered. The proposed method was applied to the design of PID controller of the high pressure rotor speed control in the flight envelope, and the control effects were evaluated by the nonlinear model. Simulation results show that the system had quick dynamic response with zero overshoot and zero steadystate error. Furthermore, a PID-fuzzy switching control scheme for aero-engine was designed, and the fuzzy switching system stability was proved. Simulations were studied to validate the applicability of the multiple PIDs fuzzy switching controller for aero-engine with wide range dynamics.

  7. Digestive Diseases Materials

    MedlinePlus

    ... NIDDK Health Information NIDDK Home NIDDK Image Library Digestive Disease, Nutrition, and Weight-control Materials Healthy eating, ... Materials Statistics Tip Sheets Catalog Home | Diabetes Materials | Digestive Diseases Materials | Kidney and Urologic Diseases Materials Online ...

  8. Corn silage management: effects of hybrid, chop length, and mechanical processing on digestion and energy content.

    PubMed

    Johnson, L M; Harrison, J H; Davidson, D; Mahanna, W C; Shinners, K

    2003-01-01

    Two experiments were conducted to evaluate the effects of chop length and mechanical processing of two hybrids of whole plant corn on digestion and energy content of the total mixed ration (TMR). The experimental designs in experiments 1 and 2 were 6 x 6 and 4 x 4 Latin squares, respectively. In the first experiment, Pioneer hybrid 3845 was harvested at three theoretical lengths of cut: 11.1, 27.8, and 39.7 mm. At each chop length, corn was harvested with and without mechanical processing using a John Deere 5830 harvester with an onboard kernel processor. In the second experiment, Pioneer hybrid Quanta was harvested at two theoretical lengths of cut: 27.8 and 39.7 mm, with and without mechanical processing. In both experiments, the increase in the theoretical length of cut of corn silage increased the average length of cut and tended to increase the percentage of particles greater than 19 mm and lower the percentage of particles between 8 and 19 mm. In experiment 1, apparent total tract dry matter, organic matter, and neutral detergent fiber (NDF) digestibilities were lower for cows fed diets containing corn silage harvested at a short chop length (11.1 mm) than for corn silage harvested at a long chop length (39.7 mm). The lower total tract digestibility of nutrients may have contributed to the lower TDN, metabolizable energy (percentage of digestible energy), and NEL concentration of diets containing the short chop length corn silage (experiment 1). In experiment 2, total tract starch digestibility was greater for cows fed medium chop (27.8 mm) corn silage diets, and total tract NDF digestibility was greater for cows fed long chop (39.7 mm) corn silage diets. The opposing effect of total tract starch and fiber digestibilities between chop lengths may have contributed to the lack of difference in energy content of the diets in experiment 2. The TDN and NEL concentrations of the processed corn silage diets were greater than the unprocessed corn silage diets in

  9. Phosphorus digestibility and phytate degradation by yearlings and mature horses.

    PubMed

    Fowler, A L; Hansen, T L; Strasinger, L A; Harlow, B E; Lawrence, L M

    2015-12-01

    Inorganic P is often added to growing horse diets because organic P, or phytate-P, is believed to have lower digestibility. If horses can efficiently digest organic P, then the need for inorganic P may be reduced. Much of the P in grain-based concentrates fed to growing horses is in the form of phytate-P. Little is known about the ability of growing horses to degrade phytate-P or whether horse age affects mineral digestion in horses. The objective of this study was to examine the effect of age on P, Ca, and Mg digestibility as well as phytate-P degradation. Four yearling geldings and 4 mature geldings were fed a diet of alfalfa cubes, timothy cubes, and a pelleted concentrate. The diet contained 0.28% total P and 17.4% of that P was in the phytate form. There was a 14-d diet adaptation period followed by a 4-d fecal collection period. Apparent total tract P digestibility was higher for yearlings than mature geldings ( = 0.036; 7.7 and -6.6% for yearlings and mature geldings, respectively). Phytate-P disappearance was 94.8% and did not differ between ages ( = 0.190). Apparent Ca digestibility was lower in mature geldings ( = 0.043), but apparent Mg digestibility did not differ between ages ( = 0.414). Phytate is broken down in the gastrointestinal tract, but the low P digestibilities suggest that either degradation occurs after the site of P absorption or liberated P is recycled back into the gastrointestinal tract. Yearlings can utilize organic P as well as mature horses; therefore, diets without inorganic P are acceptable for growing horses.

  10. Digestive Diseases A-Z

    MedlinePlus

    ... Home Health Information Digestive Diseases English English Español Digestive Diseases The digestive system made up of the ... Upper GI Endoscopy Upper GI Series Virtual Colonoscopy Digestive Disease Topics Abdominal Adhesions Acid Reflux (GER & GERD) ...

  11. On Proper Selection of Multihop Relays for Future Enhancement of AeroMACS Networks

    NASA Technical Reports Server (NTRS)

    Kamali, Behnam; Kerczewski, Robert J.; Apaza, Rafael D.

    2015-01-01

    As the Aeronautical Mobile Airport Communications System (AeroMACS) has evolved from a technology concept to a deployed communications network over major US airports, it is now time to contemplate whether the existing capacity of AeroMACS is sufficient to meet the demands set forth by all fixed and mobile applications over the airport surface given the AeroMACS constraints regarding bandwidth and transmit power. The underlying idea in this article is to present IEEE 802.16j-based WiMAX as a technology that can address future capacity enhancements and therefore is most feasible for AeroMACS applications. The principal argument in favor IEEE 802.16j technology is the flexible and cost effective extension of radio coverage that is afforded by relay fortified networks, with virtually no increase in the power requirements and virtually no rise in interference levels to co-allocated applications. The IEEE 802.16j-based multihop relay systems are briefly described. The focus is on key features of this technology, frame structure, and its architecture. Next, AeroMACS is described as a WiMAX-based wireless network. The two major relay modes supported by IEEE 802.16j amendment, i.e., transparent and non-transparent are described. The benefits of employing multihop relays are listed. Some key challenges related to incorporating relays into AeroMACS networks are discussed. The selection of relay type in a broadband wireless network affects a number of network parameters such as latency, signal overhead, PHY (Scalable Physical Layer) and MAC (Media Access Layer) layer protocols, consequently it can alter key network quantities of throughput and QoS (Quality of Service).

  12. Aero-Thermal Calibration of the NASA Glenn Icing Research Tunnel (2004 and 2005 Tests)

    NASA Technical Reports Server (NTRS)

    Arrington, E. Allen; Pastor, Christine M.; Gonsalez, Jose C.; Curry, Monroe R., III

    2010-01-01

    A full aero-thermal calibration of the NASA Glenn Icing Research Tunnel was completed in 2004 following the replacement of the inlet guide vanes upstream of the tunnel drive system and improvement to the facility total temperature instrumentation. This calibration test provided data used to fully document the aero-thermal flow quality in the IRT test section and to construct calibration curves for the operation of the IRT. The 2004 test was also the first to use the 2-D RTD array, an improved total temperature calibration measurement platform.

  13. Pelleted beet pulp substituted for high-moisture corn: 2. Effects on digestion and ruminal digestion kinetics in lactating dairy cows.

    PubMed

    Voelker, J A; Allen, M S

    2003-11-01

    The effects of increasing concentrations of dried, pelleted beet pulp substituted for high-moisture corn on digestion and ruminal digestion kinetics were evaluated using eight ruminally and duodenally cannulated multiparous Holstein cows in a duplicated 4 x 4 Latin square design with 21-d periods. Cows were 79 +/- 17 (mean +/- SD) d in milk at the beginning of the experiment. Experimental diets with 40% forage (corn silage and alfalfa silage) and 60% concentrate contained 0, 6.1, 12.1, or 24.3% beet pulp substituted for high-moisture corn on a dry matter basis. Diet concentrations of neutral detergent fiber (NDF) and starch were 24.3 and 34.6% (0% beet pulp), 26.2 and 30.5% (6% beet pulp), 28.0 and 26.5% (12% beet pulp), and 31.6 and 18.4% (24% beet pulp), respectively. Ruminal dry matter pool decreased and NDF turnover rate increased as dietary beet pulp content increased. Potentially digestible NDF was digested more extensively and at a faster rate in the rumen with increasing beet pulp, resulting in increased total tract NDF digestibility. Passage rates of potentially digestible NDF and of indigestible NDF were not affected by treatment. True ruminal digestibility of starch decreased with increasing beet pulp substitution. This was caused by a linear increase in starch passage rate, possibly because of increasing ruminal fill, and a linear decrease in digestion rate of starch in the rumen, possibly because of reduced amylolytic enzyme activity for lower-starch diets. Although true ruminal starch digestibility decreased when more beet pulp was fed, whole tract starch digestibility was not affected because of compensatory digestion of starch in the intestines. Due to more thorough digestion of fiber in diets containing more beet pulp, whole-tract digestibility of organic matter increased linearly, and intake of digestible organic matter was not affected. Partially replacing high-moisture corn with beet pulp in low-forage diets increased fiber digestibility without

  14. Antioxidant effects of gastrointestinal digested purple carrot extract on the human cells of colonic mucosa.

    PubMed

    Olejnik, Anna; Rychlik, Joanna; Kidoń, Marcin; Czapski, Janusz; Kowalska, Katarzyna; Juzwa, Wojciech; Olkowicz, Mariola; Dembczyński, Radosław; Moyer, Mary Pat

    2016-01-01

    Purple carrot (PC) is a potential dietary constituent, which represents a valuable source of antioxidants and can modulate the reactive oxygen species (ROS) level in the gastrointestinal tract. Antioxidant capacity of a PC extract subjected to digestion process simulated in the artificial alimentary tract, including the stomach, small intestine and colon, was analyzed in normal human cells of colon mucosa. Results indicated that the extract obtained upon passage through the gastrointestinal tract, which could come into contact with the colonic cells in situ, was less potent than the extract, which was not subjected to digestion process. Digested PC extract exhibited intracellular ROS-inhibitory capacity, with 1mg/mL showing the ROS clearance of 18.4%. A 20.7% reduction in oxidative DNA damage due to colon mucosa cells' treatment with digested PC extract was observed. These findings indicate that PC extract is capable of colonic cells' protection against the adverse effects of oxidative stress. PMID:26213078

  15. Global dust model intercomparison in AeroCom phase I

    SciTech Connect

    Huneeus, N.; Schulz, M.; Balkanski, Y.; Griesfeller, J.; Prospero, J.; Kinne, S.; Bauer, S.; Boucher, O.; Chin, M.; Dentener, F.; Diehl, T.; Easter, R.; Fillmore, D.; Ghan, S.; Ginoux, P.; Grini, A.; Horowitz, L.; Koch, D.; Krol, M. C.; Landing, W.; Liu, X.; Mahowald, N.; Miller, R.; Morcrette, J. -J.; Myhre, G.; Penner, J.; Perlwitz, J.; Stier, P.; Takemura, T.; Zender, C. S.

    2011-08-01

    This study presents the results of a broad intercomparison of a total of 15 global aerosol models within the AeroCom project. Each model is compared to observations related to desert dust aerosols, their direct radiative effect, and their impact on the biogeochemical cycle, i.e., aerosol optical depth (AOD) and dust deposition. Additional comparisons to Angström exponent (AE), coarse mode AOD and dust surface concentrations are included to extend the assessment of model performance and to identify common biases present in models. These data comprise a benchmark dataset that is proposed for model inspection and future dust model development. There are large differences among the global models that simulate the dust cycle and its impact on climate. In general, models simulate the climatology of vertically integrated parameters (AOD and AE) within a factor of two whereas the total deposition and surface concentration are reproduced within a factor of 10. In addition, smaller mean normalized bias and root mean square errors are obtained for the climatology of AOD and AE than for total deposition and surface concentration. Characteristics of the datasets used and their uncertainties may influence these differences. Large uncertainties still exist with respect to the deposition fluxes in the southern oceans. Further measurements and model studies are necessary to assess the general model performance to reproduce dust deposition in ocean regions sensible to iron contributions. Models overestimate the wet deposition in regions dominated by dry deposition. They generally simulate more realistic surface concentration at stations downwind of the main sources than at remote ones. Most models simulate the gradient in AOD and AE between the different dusty regions. However the seasonality and magnitude of both variables is better simulated at African stations than Middle East ones. The models simulate the offshore transport of West Africa throughout the year but they

  16. COMPARATIVE GUT PHYSIOLOGY SYMPOSIUM: Comparative physiology of digestion.

    PubMed

    Furness, J B; Cottrell, J J; Bravo, D M

    2015-02-01

    The digestive systems of all species have been shaped by environmental pressures over long evolutionary time spans. Nevertheless, all digestive systems must achieve the same end points, the ingestion of biological material and its conversion to molecules that serve as energy substrates and structural components of tissues. A range of strategies to extract nutrients, including for animals reliant primarily on foregut fermentation, hindgut fermentation, and enzymatic degradation, have evolved. Moreover, animals have adapted to different foodstuffs as herbivores (including frugivores, folivores, granivores, etc.), carnivores, and omnivores. We present evidence that humans have diverged from other omnivores because of the long history of consumption of cooked or otherwise prepared food. We consider them to be cucinivores. We present examples to illustrate that the range of foodstuffs that can be efficiently assimilated by each group or species is limited and is different from that of other groups or species. Differences are reflected in alimentary tract morphology. The digestive systems of each group and of species within the groups are adaptable, with constraints determined by individual digestive physiology. Although overall digestive strategies and systems differ, the building blocks for digestion are remarkably similar. All vertebrates have muscular tubular tracts lined with a single layer of epithelial cells for most of the length, use closely related digestive enzymes and transporters, and control the digestive process through similar hormones and similarly organized nerve pathways. Extrapolations among species that are widely separated in their digestive physiologies are possible when the basis for extrapolation is carefully considered. Divergence is greatest at organ or organismal levels, and similarities are greatest at the cell and molecular level.

  17. COMPARATIVE GUT PHYSIOLOGY SYMPOSIUM: Comparative physiology of digestion.

    PubMed

    Furness, J B; Cottrell, J J; Bravo, D M

    2015-02-01

    The digestive systems of all species have been shaped by environmental pressures over long evolutionary time spans. Nevertheless, all digestive systems must achieve the same end points, the ingestion of biological material and its conversion to molecules that serve as energy substrates and structural components of tissues. A range of strategies to extract nutrients, including for animals reliant primarily on foregut fermentation, hindgut fermentation, and enzymatic degradation, have evolved. Moreover, animals have adapted to different foodstuffs as herbivores (including frugivores, folivores, granivores, etc.), carnivores, and omnivores. We present evidence that humans have diverged from other omnivores because of the long history of consumption of cooked or otherwise prepared food. We consider them to be cucinivores. We present examples to illustrate that the range of foodstuffs that can be efficiently assimilated by each group or species is limited and is different from that of other groups or species. Differences are reflected in alimentary tract morphology. The digestive systems of each group and of species within the groups are adaptable, with constraints determined by individual digestive physiology. Although overall digestive strategies and systems differ, the building blocks for digestion are remarkably similar. All vertebrates have muscular tubular tracts lined with a single layer of epithelial cells for most of the length, use closely related digestive enzymes and transporters, and control the digestive process through similar hormones and similarly organized nerve pathways. Extrapolations among species that are widely separated in their digestive physiologies are possible when the basis for extrapolation is carefully considered. Divergence is greatest at organ or organismal levels, and similarities are greatest at the cell and molecular level. PMID:26020739

  18. 77 FR 35888 - Airworthiness Directives; PIAGGIO AERO INDUSTRIES S.p.A Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-15

    ... 12866, (2) Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034... PIAGGIO AERO INDUSTRIES S.p.A Model P-180 airplanes, serial numbers (S/Ns) 1002 and 1004 through 1223... flap external screwjacks installed during production. (g) Credit for Actions Accomplished in...

  19. 78 FR 22168 - Airworthiness Directives; International Aero Engines AG Turbofan Engines

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-15

    ... published in the Federal Register on January 9, 2013 (78 FR 1776). That NPRM proposed to require the... ``significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not.... SUMMARY: We are adopting a new airworthiness directive (AD) for certain International Aero Engines AG...

  20. Application of Multihop Relay for Performance Enhancement of AeroMACS Networks

    NASA Technical Reports Server (NTRS)

    Kamali, Behnam; Wilson, Jeffrey D.; Kerczewski, Robert J.

    2012-01-01

    A new transmission technology, based on IEEE 802.16-2009 (WiMAX), is currently being developed for airport surface communications. A C-band spectrum allocation at 5091 to 5150 MHz has been created by International Telecommunications Union (ITU) to carry this application. The proposed technology, known as AeroMACS, will be used to support fixed and mobile ground to ground applications and services. This article proposes and demonstrates that IEEE 802.16j-amendment-based WiMAX is most feasible for AeroMACS applications. This amendment introduces multihop relay as an optional deployment that may be used to provide additional coverage and/or enhance the capacity of the network. Particular airport surface radio coverage situations for which IEEE 802.16-2009-WiMAX provides resolutions that are inefficient, costly, or excessively power consuming are discussed. In all these cases, it is argued that 16j technology offers a much better alternative. A major concern about deployment of AeroMACS is interference to co-allocated applications such as the Mobile Satellite Service (MSS) feeder link. Our initial simulation results suggest that no additional interference to MSS feeder link is caused by deployment of IEEE 802.16j-based AeroMACS.

  1. Numerical analysis of the aero-optic effects induced by the turbulence field surrounding hypersonic aircrafts

    NASA Astrophysics Data System (ADS)

    Yang, Wenxia; Cai, Chao; Ding, Mingyue; Zhou, Chengping; Guo, Xiaoxing

    2007-11-01

    The goal of this paper is to numerically simulate and analyze the aero-optic effects caused by the hyper-speed turbulence fields surrounding the aircraft under different flight conditions, and to characterize them with the associated optical transfer functions. First, analysis and computation of the aero-optic effects under different flight conditions have been addressed, where the parameters characterizing the hyper-speed turbulence field were obtained by solving its N-S equations via CFD methods. The infrared ray trajectories passing through the flow field with a non-homogeneous distribution of the refraction indices were acquired using the gradient index ray-tracing method, and the transfer function to represent the aero-optic effects was derived considering the principles of Fourier optics. The simulation results showed that the aero-optic transfer function is characterized as a low-pass filter of nonlinearly varying phases, which results the blurring and shifting of the objects in the acquired images.

  2. Finite element model for aero-elastically tailored residential wind turbine blade design

    NASA Astrophysics Data System (ADS)

    Robinson, Eric Alan

    Advances in passive wind turbine control systems have allowed wind turbines to achieve higher efficiencies and operate in wider inflow conditions than ever before. Within recent years, the adoption of aero-elastically tailored (bend-twist coupled) composite blades have been a pursued strategy. Unfortunately, for this strategy to be applied, traditional means of modeling, designing and manufacturing are no longer adequate. New parameters regarding non-linearities in deflections, stiffness, and aerodynamic loadings must now be implemented. To aid in the development of passive wind turbine system design, a finite element based aero-elastic program capable of computationally predicting blade deflection and twist under loading was constructed. The program was built around the idea of iteratively solving a blade composite structure to reach a maximum aero-elastic twist configuration under elevated wind speeds. Adopting a pre-existing blade geometry, from a pitch controlled small scale (3.5kW) turbine design, the program was tested to discover the geometry bend-twist coupling potential. This research would be a contributing factor in designing a passive pitch control replacement system for the turbine. A study of various model loading configurations was first performed to insure model validity. Then, a final model was used to analyze composite layups for selected spar configurations. Results characterize the aero-elastic twist properties for the selected configurations.

  3. Application of Multihop Relay for Performance Enhancement of AeroMACS Networks

    NASA Technical Reports Server (NTRS)

    Kamali, Behnam; Wilson, Jeffrey D.; Kerczewski, Robert J.

    2012-01-01

    A new transmission technology, based on IEEE 802.16-2009 (WiMAX), is currently being developed for airport surface communications. A C-band spectrum allocation at 5091-5150 MHz has been created by ITU to carry this application. The proposed technology, known as AeroMACS, will be used to support fixed and mobile ground to ground applications and services. This article proposes and demonstrates that IEEE 802.16j-amendment-based WiMAX is most feasible for AeroMACS applications. This amendment introduces multihop relay as an optional deployment that may be used to provide additional coverage and/or enhance the capacity of the network. Particular airport surface radio coverage situations for which IEEE 802.16-2009-WiMAX provides resolutions that are inefficient, costly, or excessively power consuming are discussed. In all these cases, it is argued that 16j technology offers a much better alternative. A major concern about deployment of AeroMACS is interference to co-allocated applications such as the Mobile Satellite Service (MSS) feeder link. Our initial simulation results suggest that no additional interference to MSS feeder link is caused by deployment of IEEE 802.16j-based AeroMACS.

  4. Swept Blade Aero-Elastic Model for a Small Wind Turbine (Presentation)

    SciTech Connect

    Damiani, R.; Lee, S.; Larwood, S.

    2014-07-01

    A preprocessor for analyzing preswept wind turbines using the in-house aero-elastic tool coupled with a multibody dynamic simulator was developed. A baseline 10-kW small wind turbine with straight blades and various configurations that featured bend-torsion coupling via blade-tip sweep were investigated to study their impact on ultimate loads and fatigue damage equivalent loads.

  5. OC3 -- Benchmark Exercise of Aero-Elastic Offshore Wind Turbine Codes: Preprint

    SciTech Connect

    Passon, P.; Kuhn, M.; Butterfield, S.; Jonkman, J.; Camp, T.; Larsen, T. J.

    2007-08-01

    This paper introduces the work content and status of the first international investigation and verification of aero-elastic codes for offshore wind turbines as performed by the "Offshore Code Comparison Collaboration" (OC3) within the "IEA Wind Annex XXIII -- Subtask 2".

  6. AERO: A Decision Support Tool for Wind Erosion Assessment in Rangelands and Croplands

    NASA Astrophysics Data System (ADS)

    Galloza, M.; Webb, N.; Herrick, J.

    2015-12-01

    Wind erosion is a key driver of global land degradation, with on- and off-site impacts on agricultural production, air quality, ecosystem services and climate. Measuring rates of wind erosion and dust emission across land use and land cover types is important for quantifying the impacts and identifying and testing practical management options. This process can be assisted by the application of predictive models, which can be a powerful tool for land management agencies. The Aeolian EROsion (AERO) model, a wind erosion and dust emission model interface provides access by non-expert land managers to a sophisticated wind erosion decision-support tool. AERO incorporates land surface processes and sediment transport equations from existing wind erosion models and was designed for application with available national long-term monitoring datasets (e.g. USDI BLM Assessment, Inventory and Monitoring, USDA NRCS Natural Resources Inventory) and monitoring protocols. Ongoing AERO model calibration and validation are supported by geographically diverse data on wind erosion rates and land surface conditions collected by the new National Wind Erosion Research Network. Here we present the new AERO interface, describe parameterization of the underpinning wind erosion model, and provide a summary of the model applications across agricultural lands and rangelands in the United States.

  7. Simultaneous measurement of aero-optical distortion and turbulent structure in a heated boundary layer

    NASA Astrophysics Data System (ADS)

    Saxton-Fox, Theresa; McKeon, Beverley; Smith, Adam; Gordeyev, Stanislav

    2014-11-01

    This study examines the relationship between turbulent structures and the aero-optical distortion of a laser beam passing through a turbulent boundary layer. Previous studies by Smith et al. (AIAA, 2014--2491) have found a bulk convection velocity of 0 . 8U∞ for aero-optical distortion in turbulent boundary layers, motivating a comparison of the distortion with the outer boundary layer. In this study, a turbulent boundary layer is developed over a flat plate with a moderately-heated section of length 25 δ . Density variation in the thermal boundary layer leads to aero-optical distortion, which is measured with a Malley probe (Smith et al., AIAA, 2013--3133). Simultaneously, 2D PIV measurements are recorded in a wall-normal, streamwise plane centered on the Malley probe location. Experiments are run at Reθ = 2100 and at a Mach number of 0.03, with the heated wall 10 to 20°C above the free stream temperature. Correlations and conditional averages are carried out between Malley probe distortion angles and flow features in the PIV vector fields. Aero-optical distortion in this study will be compared to distortion in higher Mach number flows studied by Gordeyev et al. (J. Fluid Mech., 2014), with the aim of extending conclusions into compressible flows. This research is made possible by the Department of Defense through the National Defense & Engineering Graduate Fellowship (NDSEG) Program and by the Air Force Office of Scientific Research Grant # FA9550-12-1-0060.

  8. 76 FR 60396 - Airworthiness Directives; Piaggio Aero Industries S.p.A. Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-29

    ... 12866; 2. Is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034... Industries S.p.A. Airplanes AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT... (AD) for certain Piaggio Aero Industries S.p.A. Model P-180 airplanes. This proposed AD results...

  9. 78 FR 69600 - Airworthiness Directives; Piaggio Aero Industries S.p.A Airplanes

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-20

    ... Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not affect intrastate aviation in Alaska... Industries S.p.A Airplanes AGENCY: Federal Aviation Administration (FAA), Department of Transportation (DOT... (AD) for certain Piaggio Aero Industries S.p.A. Model P-180 airplanes. This proposed AD results...

  10. Efficacy of predictive wavefront control for compensating aero-optical aberrations

    NASA Astrophysics Data System (ADS)

    Goorskey, David J.; Schmidt, Jason; Whiteley, Matthew R.

    2013-07-01

    Imaging and laser beam propagation from airborne platforms are degraded by dynamic aberrations due to air flow around the aircraft, aero-mechanical distortions and jitter, and free atmospheric turbulence. For certain applications, like dim-object imaging, free-space optical communications, and laser weapons, adaptive optics (AO) is necessary to compensate for the aberrations in real time. Aero-optical flow is a particularly interesting source of aberrations whose flowing structures can be exploited by adaptive and predictive AO controllers, thereby realizing significant performance gains. We analyze dynamic aero-optical wavefronts to determine the pointing angles at which predictive wavefront control is more effective than conventional, fixed-gain, linear-filter control. It was found that properties of the spatial decompositions and temporal statistics of the wavefronts are directly traceable to specific features in the air flow. Furthermore, the aero-optical wavefront aberrations at the side- and aft-looking angles were the most severe, but they also benefited the most from predictive AO.

  11. FJ44 Turbofan Engine Test at NASA Glenn Research Center's Aero-Acoustic Propulsion Laboratory

    NASA Technical Reports Server (NTRS)

    Lauer, Joel T.; McAllister, Joseph; Loew, Raymond A.; Sutliff, Daniel L.; Harley, Thomas C.

    2009-01-01

    A Williams International FJ44-3A 3000-lb thrust class turbofan engine was tested in the NASA Glenn Research Center s Aero-Acoustic Propulsion Laboratory. This report presents the test set-up and documents the test conditions. Farfield directivity, in-duct unsteady pressures, duct mode data, and phased-array data were taken and are reported separately.

  12. Dependence of AeroMACS Interference on Airport Radiation Pattern Characteristics

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey D.

    2012-01-01

    AeroMACS (Aeronautical Mobile Airport Communications System), which is based upon the IEEE 802.16e mobile wireless standard, is expected to be implemented in the 5091 to 5150 MHz frequency band. As this band is also occupied by Mobile Satellite Service (MSS) feeder uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference are under analysis in order to enable the definition of standards that assure that such interference will be avoided. In this study, the cumulative interference power distribution at low earth orbit from AeroMACS transmitters at the 497 major airports in the contiguous United States was simulated with the Visualyse Professional software. The dependence of the interference power on the number of antenna beams per airport, gain patterns, and beam direction orientations was simulated. As a function of these parameters, the simulation results are presented in terms of the limitations on transmitter power required to maintain the cumulative interference power under the established threshold.

  13. Dependence of AeroMACS Interference on Airport Radiation Pattern Characteristics

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey D.

    2012-01-01

    AeroMACS (Aeronautical Mobile Airport Communications System), which is based upon the IEEE 802.16e mobile wireless standard, is expected to be implemented in the 5091-5150 MHz frequency band. As this band is also occupied by Mobile Satellite Service (MSS) feeder uplinks, AeroMACS must be designed to avoid interference with this incumbent service. The aspects of AeroMACS operation that present potential interference are under analysis in order to enable the definition of standards that assure that such interference will be avoided. In this study, the cumulative interference power distribution at low earth orbit from AeroMACS transmitters at the 497 major airports in the contiguous United States was simulated with the Visualyse Professional software. The dependence of the interference power on the number of antenna beams per airport, gain patterns, and beam direction orientations was simulated. As a function of these parameters, the simulation results are presented in terms of the limitations on transmitter power required to maintain the cumulative interference power under the established threshold.

  14. Computational methods to compute wavefront error due to aero-optic effects

    NASA Astrophysics Data System (ADS)

    Genberg, Victor; Michels, Gregory; Doyle, Keith; Bury, Mark; Sebastian, Thomas

    2013-09-01

    Aero-optic effects can have deleterious effects on high performance airborne optical sensors that must view through turbulent flow fields created by the aerodynamic effects of windows and domes. Evaluating aero-optic effects early in the program during the design stages allows mitigation strategies and optical system design trades to be performed to optimize system performance. This necessitates a computationally efficient means to evaluate the impact of aero-optic effects such that the resulting dynamic pointing errors and wavefront distortions due to the spatially and temporally varying flow field can be minimized or corrected. To this end, an aero-optic analysis capability was developed within the commercial software SigFit that couples CFD results with optical design tools. SigFit reads the CFD generated density profile using the CGNS file format. OPD maps are then created by converting the three-dimensional density field into an index of refraction field and then integrating along specified paths to compute OPD errors across the optical field. The OPD maps may be evaluated directly against system requirements or imported into commercial optical design software including Zemax® and Code V® for a more detailed assessment of the impact on optical performance from which design trades may be performed.

  15. The effects of dietary fiber level on nutrient digestibility in growing pigs.

    PubMed

    Zhang, Wenjuan; Li, Defa; Liu, Ling; Zang, Jianjun; Duan, Qiwu; Yang, Wenjun; Zhang, Liying

    2013-04-15

    The objective of this study was to investigate the effects of total dietary fiber level on nutrient digestibility and the relationship between apparent total tract digestibility of total dietary fiber, and soluble dietary fiber, insoluble dietary fiber and available energy. Sugar beet pulp was as the only fiber source. The experiment was designed as a 6 × 6 Latin square with an adaptation period of 7 d followed by a 5-d total collection of feces and urine. Feed intake tended to decrease (P =0.10) as total dietary fiber level increased. The apparent total tract digestibility of dry matter, crude protein and gross energy decreased (P <0.01) when total dietary fiber increased but the digestibility of soluble dietary fiber and insoluble dietary fiber increased (P <0.01). The digestible energy and metabolizable energy content of diets decreased (P <0.01) as the total dietary fiber increased.

  16. Infant digestion physiology and the relevance of in vitro biochemical models to test infant formula lipid digestion.

    PubMed

    Poquet, Laure; Wooster, Tim J

    2016-08-01

    Lipids play an important role in the diet of preterm and term infants providing a key energy source and essential lipid components for development. While a lot is known about adult lipid digestion, our understanding of infant digestion physiology is still incomplete, the greatest gap being on the biochemistry of the small intestine, particularly the activity and relative importance of the various lipases active in the intestine. The literature has been reviewed to identify the characteristics of lipid digestion of preterm and term infants, but also to better understand the physiology of the infant gastrointestinal tract compared to adults that impacts the absorption of lipids. The main differences are a higher gastric pH, submicellar bile salt concentration, a far more important role of gastric lipases as well as differences at the level of the intestinal barrier. Importantly, the consequences of improper in vitro replication of gastric digestions conditions (pH and lipase specificity) are demonstrated using examples from the most recent of studies. It is true that some animal models could be adapted to study infant lipid digestion physiology, however the ethical relevance of such models is questionable, hence the development of accurate in vitro models is a must. In vitro models that combine up to date knowledge of digestion biochemistry with intestinal cells in culture are the best choice to replicate digestion and absorption in infant population, this would allow the adaptation of infant formula for a better digestion and absorption of dietary lipids by preterm and term infants. PMID:27279140

  17. Infant digestion physiology and the relevance of in vitro biochemical models to test infant formula lipid digestion.

    PubMed

    Poquet, Laure; Wooster, Tim J

    2016-08-01

    Lipids play an important role in the diet of preterm and term infants providing a key energy source and essential lipid components for development. While a lot is known about adult lipid digestion, our understanding of infant digestion physiology is still incomplete, the greatest gap being on the biochemistry of the small intestine, particularly the activity and relative importance of the various lipases active in the intestine. The literature has been reviewed to identify the characteristics of lipid digestion of preterm and term infants, but also to better understand the physiology of the infant gastrointestinal tract compared to adults that impacts the absorption of lipids. The main differences are a higher gastric pH, submicellar bile salt concentration, a far more important role of gastric lipases as well as differences at the level of the intestinal barrier. Importantly, the consequences of improper in vitro replication of gastric digestions conditions (pH and lipase specificity) are demonstrated using examples from the most recent of studies. It is true that some animal models could be adapted to study infant lipid digestion physiology, however the ethical relevance of such models is questionable, hence the development of accurate in vitro models is a must. In vitro models that combine up to date knowledge of digestion biochemistry with intestinal cells in culture are the best choice to replicate digestion and absorption in infant population, this would allow the adaptation of infant formula for a better digestion and absorption of dietary lipids by preterm and term infants.

  18. Urinary Tract Infections

    MedlinePlus

    ... body's drainage system for removing wastes and extra water. It includes two kidneys, two ureters, a bladder, and a urethra. Urinary tract infections (UTIs) are the second most common type of infection in the body. You may have a UTI if you notice ...

  19. (Methane digester). Final report

    SciTech Connect

    Waybright, R.C.

    1981-01-01

    The purpose of the grant was to construct and operate a methane digester for dairy manure involving the latest state-of-the-art technics. The first step taken was to empty out the existing digester to evaluate its performance and to gain ideas of how to build the next digester so it would operate more efficiently. Next, the design criteria was set up in order to eliminate some problems involved with the first digester and also new ideas as to how to build the next one without a protective building and testing simplified construction technics. After this the digester construction was started with the completion date in late January. The digester was then filled and operated at different temperatures attempting to achieve the optimum operating range.

  20. Digestive Physiological Characteristics of the Gobiidae

    PubMed Central

    Hur, Sang-Woo; Kim, Shin-Kwon; Kim, Dae-Jung; Lee, Bae-Ik; Park, Su-Jin; Hwang, Hyung-Gyu; Jun, Je-Cheon; Myeong, Jeong-In; Lee, Chi-Hoon; Lee, Young-Don

    2016-01-01

    In this study, we investigated the characteristics of CCK-producing cells and mucus-secreting goblet cells with respect to stomach fish and stomachless fish of the Gobiidae in order to provide a basis for understanding the digestive physiology. Hairychin goby (Sagamia geneionema), which is stomachless fish, the numbers of mucus-secreting goblet cells is highest in the posterior intestine portion (P<0.05), while CCK-producing cells are scattered throughout the intestine. Gluttonous goby (Chasmichthys gulosus), which is stomach fish, mucus-secreting goblet cells are most abundant in the mid intestine portion (P<0.05), whereas CCK-producing cells are observed only in the anterior and mid intestine portion. Trident goby (Tridentiger obscurus) which is stomach fish, mucus-secreting goblet cells were most abundant in the mid intestine portion (P<0.05). CCK-producing cells are found in the anterior and mid intestine portion. Giurine goby, Rhinogobius giurinus which is also stomach fish, the largest number of mucus-secreting goblet cells showed in anterior intestine portion except for esophagus (P<0.05). CCK-producing cells are present only in the anterior and mid intestine portion. In S. geneionema, digestive action occurs in the posterior intestine portion to protect and functions to activate digestion. In contrast, in C. gulosus, T. obscurus and R. giurinus, their digestive action occurs in the anterior and mid intestine portion to protect and functions to activate digestion. Further studies of the modes of food ingestion by these fish, the contents of their digestive tracts, and the staining characteristics of the goblet cells need to be carried out.

  1. Non-hydrolyzed in digestive tract and blood natural L-carnosine peptide ("bioactivated Jewish penicillin") as a panacea of tomorrow for various flu ailments: signaling activity attenuating nitric oxide (NO) production, cytostasis, and NO-dependent inhibition of influenza virus replication in macrophages in the human body infected with the virulent swine influenza A (H1N1) virus.

    PubMed

    Babizhayev, Mark A; Deyev, Anatoliy I; Yegorov, Yegor E

    2013-01-01

    in excessive amounts mediate the overreaction of the host's immune response against the organs or tissues in which viruses are replicating, and this may explain the mechanism of tissue injuries observed in influenza virus infection of various types. In this article, the types of protection of carnosine in its bioavailable non-hydrolyzed forms in formulations are considered against reactive oxygen radical species-dependent injury, peroxynitrite damage, and other types of viral injuries in which impaired immune responses to viral pathogens are usually involved. Carnosine (β-alanyl-L-histidine) shows the pharmacological intracellular correction of NO release, which might be one of the important factors of natural immunity in controlling the initial stages of influenza A virus infection (inhibition of virus replication) and virus-induced regulation of cytokine gene expression. The protective effects of orally applied non-hydrolyzed formulated species of carnosine include at least the direct interaction with NO, inhibition of cytotoxic NO-induced proinflammatory condition, and attenuation of the effects of cytokines and chemokines that can exert profound effects on inflammatory cells. These data are consistent with the hypothesis that natural products, such as chicken soup and chicken breast extracts rich in carnosine and its derivative anserine (β-alanyl-1-methyl-L-histidine), could contribute to the pathogenesis and prevention of influenza virus infections and cold but have a limitation due to the susceptibility to enzymatic hydrolysis of dipeptides with serum carnosinase and urine excretion after oral ingestion of a commercial chicken extract. The formulations of non-hydrolyzed in digestive tract and blood natural carnosine peptide and isopeptide (γ-glutamyl-carnosine) products, manufactured at the cGMP-certified facility and patented by the authors, have promise in the control and prevention of influenza A (H1N1) virus infection, cough, and cold.

  2. Non-hydrolyzed in digestive tract and blood natural L-carnosine peptide ("bioactivated Jewish penicillin") as a panacea of tomorrow for various flu ailments: signaling activity attenuating nitric oxide (NO) production, cytostasis, and NO-dependent inhibition of influenza virus replication in macrophages in the human body infected with the virulent swine influenza A (H1N1) virus.

    PubMed

    Babizhayev, Mark A; Deyev, Anatoliy I; Yegorov, Yegor E

    2013-01-01

    in excessive amounts mediate the overreaction of the host's immune response against the organs or tissues in which viruses are replicating, and this may explain the mechanism of tissue injuries observed in influenza virus infection of various types. In this article, the types of protection of carnosine in its bioavailable non-hydrolyzed forms in formulations are considered against reactive oxygen radical species-dependent injury, peroxynitrite damage, and other types of viral injuries in which impaired immune responses to viral pathogens are usually involved. Carnosine (β-alanyl-L-histidine) shows the pharmacological intracellular correction of NO release, which might be one of the important factors of natural immunity in controlling the initial stages of influenza A virus infection (inhibition of virus replication) and virus-induced regulation of cytokine gene expression. The protective effects of orally applied non-hydrolyzed formulated species of carnosine include at least the direct interaction with NO, inhibition of cytotoxic NO-induced proinflammatory condition, and attenuation of the effects of cytokines and chemokines that can exert profound effects on inflammatory cells. These data are consistent with the hypothesis that natural products, such as chicken soup and chicken breast extracts rich in carnosine and its derivative anserine (β-alanyl-1-methyl-L-histidine), could contribute to the pathogenesis and prevention of influenza virus infections and cold but have a limitation due to the susceptibility to enzymatic hydrolysis of dipeptides with serum carnosinase and urine excretion after oral ingestion of a commercial chicken extract. The formulations of non-hydrolyzed in digestive tract and blood natural carnosine peptide and isopeptide (γ-glutamyl-carnosine) products, manufactured at the cGMP-certified facility and patented by the authors, have promise in the control and prevention of influenza A (H1N1) virus infection, cough, and cold. PMID:23425625

  3. Digestive complications of gallstones lost during laparoscopic cholecystectomy

    PubMed Central

    Elhadad, A

    2003-01-01

    Introduction Serious complications can ensue if a gallstone is dropped into the peritoneal cavity during laparoscopic cholecystectomy and not retrieved. Case outline A 75-year-old-man was admitted with intestinal obstruction 8 years after laparoscopic cholecystectomy. Ultrasound scan and a contrast x-ray of the small bowel showed a gallstone within the small bowel lumen that CT scan had failed to identify. Laparotomy showed a Meckel's diverticulum plus a 4×6-cm gallstone in the terminal ileum. The gallstone had penetrated into the Meckel's diverticulum before migrating into the ileum and obstructing it. Discussion Gallstones lost during laparoscopic cholecystectomy can cause an intraperitoneal abscess. In addition, they can migrate through the anterior or posterior abdominal wall or the diaphragm and into the urinary tract or bronchus. The resulting abscess can obstruct the digestive tract or drain into the digestive tract to cause a communicating abscess. It can also drain through the abdominal wall and the digestive tract to cause an enterocutaneous fistula. Lastly, the stone can migrate into the intestine and cause gallstone ileus. Following laparoscopic cholecystectomy, patients with a lost gallstone may suffer from abdominal pain and fever within days or months. Thus, all dropped gallstones should be removed during laparoscopy. PMID:18332969

  4. Understanding Aero-Fractures using optics and acoustics

    NASA Astrophysics Data System (ADS)

    Turkaya, Semih; Toussaint, Renaud; Kvalheim Eriksen, Fredrik; Zecevic, Megan; Daniel, Guillaume; Grude Flekkøy, Eirik; Jørgen Måløy, Knut

    2016-04-01

    exponent p value around 0.5. An analytical model of overpressure diffusion predicting p = 0.5 and two other free parameters of the Omori Law (prefactor and origin time) is developed. The spatial density of the seismic events, and the time of end of formation of the channels can also be predicted using this developed model. Using direct simulations of acoustic emissions due to the air vibration in opening fractal cavities, the evolution in the power spectrum is investigated. 1. Turkaya S, Toussaint R, Eriksen FK, Zecevic M, Daniel G, Flekkøy EG, Måløy KJ. "Bridging aero-fracture evolution with the characteristics of the acoustic emissions in a porous medium." Front. Phys.3:70. 2015 doi: 10.3389/fphy.2015.00070

  5. Anaerobic Digestion and its Applications

    EPA Science Inventory

    Anaerobic digestion is a natural biological process. The initials "AD" may refer to the process of anaerobic digestion, or the built systems of anaerobic digesters. While there are many kinds of digesters, the biology is basically the same for all. Anaerobic digesters are built...

  6. Histological study on the digestive system development of Takifugu rubripes larvae and juvenile

    NASA Astrophysics Data System (ADS)

    Wan, Zhenzhen; Gao, Tianxiang; Zhang, Xiumei; Chen, Chao; Yu, Changhong

    2006-01-01

    The digestive tract of Takifugu rubripes during early life stages was studied with light microscopy. At the beginning of hatching, the digestive tract is represented by a simple and undifferentiated straight tube and does not communicate with the exterior, as the mouth and anus are not open yet. At 2 d after hatching, a constriction between intestine and rectum that will become the intestino-rectal valve is visible. During the endogenous feeding phase, the yolk sac is resorbed and the digestive tract becomes functional and differentiated. The liver and pancreas also become apparent at this time. At onset of exogenous feeding (3 d after hatching), yolk sac resesves are not completely depleted, suggesting a period of mixed nutrition. The digestive tract differentiates fully into buccopharynx, esophagus, stomach, intestine and rectum. At 9 d after hatching, the yolk sac reserves are completely depleted. The most noticeable events occurring from 5 to 17 d after hatching are the transformation of the epithelia type, the differentiation of the pneumatic sac, the epithelial cell, gut convolution, mucosal fold increase, and the growth of liver and pancreas. From 18 to 27 d after hatching, the numbers of intestine folds and mucus cells increase progressively. From then on, morphological changes of digestive features are almost completed. At 27 d after hatching, the morphology and function of digestive system are similar to that of the adult.

  7. Urinary Tract Infections (For Kids)

    MedlinePlus

    ... time. And when you do, phew! Your pee smells bad. These changes occur because bacteria have caused an infection somewhere in your urinary tract. Let's find out more. What Exactly Is a Urinary Tract? Your urinary tract is actually a system made up of these main parts: two kidneys ...

  8. Postcircumcision urinary tract infection.

    PubMed

    Cohen, H A; Drucker, M M; Vainer, S; Ashkenasi, A; Amir, J; Frydman, M; Varsano, I

    1992-06-01

    The possible association of urinary tract infection (UTI) with ritual circumcision on the eighth day of life was studied by analyzing the epidemiology of urinary tract infections during the first year of life in 169 children with UTI (56 males and 113 females) born in Israel from 1979 to 1984. Forty-eight percent of the episodes of UTI occurring in males appeared during the 12 days following circumcision, and the increased incidence during that period was highly significant. The median age of the males at the time of the UTI was 16 days, compared with seven months in females. Ritual Jewish circumcision as practiced in Israel may be a predisposing factor for UTI during the 12-day period following that procedure.

  9. Current Progress of a Finite Element Computational Fluid Dynamics Prediction of Flutter for the AeroStructures Test Wing

    NASA Technical Reports Server (NTRS)

    Arena, Andrew S., Jr.

    2002-01-01

    This progress report focuses on the use of the STructural Analysis RoutineS suite program, SOLIDS, input for the AeroStructures Test Wing. The AeroStructures Test Wing project as a whole is described. The use of the SOLIDS code to find the mode shapes of a structure is discussed. The frequencies, and the structural dynamics to which they relate are examined. The results of the CFD predictions are compared to experimental data from a Ground Vibration Test.

  10. Digestive capacity predicts diet diversity in Neotropical frugivorous bats.

    PubMed

    Saldaña-Vázquez, Romeo A; Ruiz-Sanchez, Eduardo; Herrera-Alsina, Leonel; Schondube, Jorge E

    2015-09-01

    1. Predicting the diet diversity of animals is important to basic and applied ecology. Knowledge of diet diversity in animals helps us understand niche partitioning, functional diversity and ecosystem services such as pollination, pest control and seed dispersal. 2. There is a negative relationship between the length of the digestive tract and diet diversity in animals; however, the role of digestive physiology in determining diet diversity has been ignored. This is especially important in vertebrates with powered flight because, unlike non-flying vertebrates, they have limitations that may constrain gut size. 3. Here, we evaluate the relationship between digestive capacity and diet diversity in Carollinae and Stenodermatinae frugivorous bats. These bats disperse the seeds of plants that are key to Neotropical forest regeneration. 4. Our results show that digestive capacity is a good predictor of diet diversity in Carollinae and Stenodermatinae frugivorous bats (R(2) = 0·77). 5. Surprisingly, the most phylogenetically closely related species were not similar in their digestive capacity or diet diversity. The lack of a phylogenetic signal for the traits evaluated implies differences in digestive physiology and diet in closely related species. 6. Our results highlight the predictive usefulness of digestive physiology for understanding the feeding ecology of animals.

  11. Overview of NASA Glenn Research Center Programs in Aero-Heat Transfer and Future Needs

    NASA Technical Reports Server (NTRS)

    Gaugler, Raymond E.

    2002-01-01

    This presentation concentrates on an overview of the NASA Glenn Research Center and the projects that are supporting Turbine Aero-Heat Transfer Research. The principal areas include the Ultra Efficient Engine Technology (UEET) Project, the Advanced Space Transportation Program (ASTP) Revolutionary Turbine Accelerator (RTA) Turbine Based Combined Cycle (TBCC) project, and the Propulsion & Power Base R&T - Smart Efficient Components (SEC), and Revolutionary Aeropropulsion Concepts (RAC) Projects. In addition, highlights are presented of the turbine aero-heat transfer work currently underway at NASA Glenn, focusing on the use of the Glenn-HT Navier- Stokes code as the vehicle for research in turbulence & transition modeling, grid topology generation, unsteady effects, and conjugate heat transfer.

  12. Computational Aero-acoustics As a Tool For Turbo-machinery Noise Reduction

    NASA Technical Reports Server (NTRS)

    Dyson, Rodger W.

    2003-01-01

    This talk will provide an overview of the field of computational aero-acoustics and its use in fan noise prediction. After a brief history of computational fluid dynamics, some of the recent developments in computational aero-acoustics will be explored. Computational issues concerning sound wave production, propagation, and reflection in practical turbo-machinery applications will be discussed including: (a) High order/High Resolution Numerical Techniques. (b) High Resolution Boundary Conditions. [c] MIMD Parallel Computing. [d] Form of Governing Equations Useful for Simulations. In addition, the basic design of our Broadband Analysis Stator Simulator (BASS) code and its application to a 2 D rotor wake-stator interaction will be shown. An example of the noise produced by the wakes from a rotor impinging upon a stator cascade will be shown.

  13. Global Mobile Satellite Service Interference Analysis for the AeroMACS

    NASA Technical Reports Server (NTRS)

    Wilson, Jeffrey D.; Apaza, Rafael D..; Hall, Ward; Phillips, Brent

    2013-01-01

    The AeroMACS (Aeronautical Mobile Airport Communications System), which is based on the IEEE 802.16-2009 mobile wireless standard, is envisioned as the wireless network which will cover all areas of airport surfaces for next generation air transportation. It is expected to be implemented in the 5091-5150 MHz frequency band which is also occupied by mobile satellite service uplinks. Thus the AeroMACS must be designed to avoid interference with this incumbent service. Simulations using Visualyse software were performed utilizing a global database of 6207 airports. Variations in base station and subscriber antenna distribution and gain pattern were examined. Based on these simulations, recommendations for global airport base station and subscriber antenna power transmission limitations are provided.

  14. Large Wind Turbine Rotor Design using an Aero-Elastic / Free-Wake Panel Coupling Code

    NASA Astrophysics Data System (ADS)

    Sessarego, Matias; Ramos-García, Néstor; Shen, Wen Zhong; Nørkær Sørensen, Jens

    2016-09-01

    Despite the advances in computing resources in the recent years, the majority of large wind-turbine rotor design problems still rely on aero-elastic codes that use blade element momentum (BEM) approaches to model the rotor aerodynamics. The present work describes an approach to wind-turbine rotor design by incorporating a higher-fidelity free-wake panel aero-elastic coupling code called MIRAS-FLEX. The optimization procedure includes a series of design load cases and a simple structural design code. Due to the heavy MIRAS-FLEX computations, a surrogate-modeling approach is applied to mitigate the overall computational cost of the optimization. Improvements in cost of energy, annual energy production, maximum flap-wise root bending moment, and blade mass were obtained for the NREL 5MW baseline wind turbine.

  15. [Carcinosarcomas in female genital tracts: general review].

    PubMed

    Guy, Jean-Baptiste; Trone, Jane-Chloé; Casteillo, François; Forest, Fabien; Pacaut, Cécile; Moncharmont, Coralie; Espenel, Sophie; Vallard, Alexis; Langrand Escure, Julien; Collard, Olivier; Peoc'h, Michel; Magné, Nicolas

    2014-01-01

    Carcinosarcoma, also known as mixed mesodermal tumor or malignant mixed Mullerian tumor (MMMT) is a pathological entity combining a sarcomatous and a carcinomatous component. Found in thoracic, digestive, genitourinary, liver or skin locations, the most common location is the female genital tract. In gynecological tumors, carcinosarcoma accounts for about 2-5% of endometrial cancers, and 1% of ovarian cancers. To date, there is no consensus on the therapeutic strategy. It relies mostly on maximum cytoreductive surgery. Adjuvant therapy remains controversial, and few prospective studies investigating its interest. Retrospective studies show the benefits of adjuvant chemotherapy based on platinum in most cases. Radiation therapy has a place in the adjuvant situations of endometrial and cervical carcinosarcoma. A more detailed pathological knowledge, and the use of targeted therapies may be promising in this histological subtype whose prognosis remains very poor. The objective of this study is to present the main principles of carcinosarcoma management in female genital tracts, describing pathological and prognostic features at the same time.

  16. Effects of varying dietary ratios of corn silage to alfalfa silage on digestion of neutral detergent fiber in lactating dairy cows.

    PubMed

    Lopes, F; Cook, D E; Combs, D K

    2015-09-01

    An in vivo study was performed to test an in vitro procedure and model that predicts total-tract neutral detergent fiber (NDF) digestibility for lactating dairy cattle. Corn silage (CS) and alfalfa silage (AS) were used as forages for this study. These forages had similar NDF composition, but fiber in the CS contained less indigestible NDF compared with AS (35.5 and 47.8% of indigestible NDF, respectively). The in vitro method estimated rate of digestion of alfalfa potentially digestible NDF to be approximately 2 times faster than CS fiber (6.11 and 3.21%/h, respectively). Four diets were formulated containing different proportions of CS to AS: 100CS:0AS, 67CS:33AS, 33CS:67AS, and 0CS:100AS, as percentage of diet DM basis. The objective was to construct diets that contained approximately similar levels of NDF but with different pool sizes and rates of digestion of potentially digestible NDF. Diets were fed to 8 ruminally cannulated, multiparous, lactating dairy cows in a replicated 4×4 Latin square with 21-d periods. Total-tract fiber digestibility and fiber digestion kinetic parameters observed in vivo were compared with the values predicted by the in vitro assay and model. Total-tract NDF digestibility coefficients were similar (41.8 and 40.6% of total NDF) for the in vitro and in vivo methods, respectively. As the proportion of dietary alfalfa increased, the digestibility of NDF increased. The rate of digestion of potentially digestible NDF predicted from the in vitro assay was also similar to what was observed in vivo. Results suggest that the in vitro total-tract NDF digestibility model could be used to predict rate of fiber digestion and NDF digestibility for lactating dairy cattle.

  17. Portuguese primary school children's conceptions about digestion: identification of learning obstacles

    NASA Astrophysics Data System (ADS)

    Silva, Rui Graça; Lima, Nelson; Coquet, Eduarda; Clément, Pierre

    2004-09-01

    A cross-sectional study of Portuguese primary school pupils' conceptions on digestion and the digestive tract was carried out before and after teaching this topic. Pupils of the prior four school years (5/6 to 9/10 year old) drew what happens to a cookie inside their body. In some cases they also wrote a short text or were interviewed. To identify their level of graphic development, they produced a free-hand drawing. The main conceptual changes in explaining digestion were strongly linked to teaching. Children's previous conceptions were not epistemological obstacles to learning about digestion. The main obstacles were of didactical origin, as images of primary school books do not represent (i) the path of food from the intestine into the blood, (associated to the epistemological obstacle of the permeability of the gut wall); (ii) a clear continuous tract from stomach to anus, which causes a specific confusion at the intestine level.

  18. Urinary tract endometriosis.

    PubMed

    Koszczuk, J C; Foglietti, M; Perez, J F; Dono, F V; Thomas, R J

    1989-01-01

    Although endometriosis is a common gynecologic pathologic phenomenon, involvement of the urinary tract is relatively rare. The clinical presentation and course of urinary system disease is extremely variable, as illustrated by the seven cases presented in this report. Therapy primarily is surgical, but a thorough understanding of the disease process and a complete knowledge of the patient's history and desires for fertility conservation are necessary to plot the most appropriate treatment course. Bladder involvement is more common, and usually less devastating, than either ureteral or kidney involvement. No signs, symptoms, or physical findings are pathognomonic, and the clinician must maintain a high index of suspicion in all cases of advanced pelvic endometriosis.

  19. Urinary tract infections.

    PubMed

    Wang, Alina; Nizran, Parminder; Malone, Michael A; Riley, Timothy

    2013-09-01

    Clinical presentation helps differentiate between upper and lower urinary tract infections (UTIs). UTIs are classified as either complicated or uncomplicated. A complicated UTI is associated with an underlying condition that increases the risk of failing therapy. Primary laboratory tests for UTIs consist of urinalysis and urine culture. The most common pathogen for uncomplicated cystitis and pyelonephritis is Escherichia coli. Nitrofurantoin, fosfomycin, and trimethoprim-sulfamethoxazole are first-line therapies for acute uncomplicated cystitis. Decisions regarding antibiotic agents should be individualized based on patients' allergies, tolerability, community resistance rates, cost, and availability.

  20. Definitions of Digestive Terms

    MedlinePlus

    ... the excitability of neurons and resulting in heightened perception of signals from the gastrointestinal tract. Cholecystectomy Surgical ... has on quality of life, including the individual's perception of his or her illness. Health-related quality ...

  1. The effects of food components on the digestion of DNA by pepsin.

    PubMed

    Zhang, Yanfang; Wang, Xingyu; Pan, Xiaoming; Liu, Yu; Wang, Hanqing; Dong, Ping; Liang, Xingguo

    2016-11-01

    Recently, our study found that naked nucleic acids (NAs) can be digested by pepsin. To better understand the fate of dietary DNA in the digestive tract, in this study we investigated the effects of several food compositions on its digestion. The results showed that protein inhibited the digestion of DNA when the protein:DNA ratio was higher than 80:1 (m/m). DNA found in nucleoprotein (NA), which more closely resembles the state of DNA in food, was as efficiently digested as naked DNA. When the carbohydrate:DNA ratio was 50:1-140:1 (m/m), mono-, di- and polysaccharides did not inhibit DNA digestion. NaCl exhibited an inhibitory effect at 300 mM, whereas divalent cations (Ca(2+ )and Mg(2+)) exerted a much stronger inhibitory effect even at 50 mM. The polycation compounds (e.g. chitosan and spermine) showed a significant inhibitory effect at N/P (NH3(+)/PO4(-)) = 10:1. The close relationship between food composition and DNA digestion suggests that dietary habits and food complexes are important for understanding the in vivo fate of the ingested DNA in the digestive tract. PMID:27314759

  2. Effect of maturity and hybrid on ruminal and intestinal digestion of corn silage in dry cows.

    PubMed

    Peyrat, J; Baumont, R; Le Morvan, A; Nozière, P

    2016-01-01

    The aim of this study was to evaluate the effect of stage of maturity at harvest on extent of starch, neutral detergent fiber (NDF), and protein digestion, and rumen fermentation in dry cows fed whole-plant corn silage from different hybrids. Four nonlactating Holstein cows cannulated at the rumen and proximal duodenum were fed 4 corn silages differing in hybrid (flint vs. flint-dent) and maturity stage (early vs. late) in a 4 × 4 Latin square design. From early to late maturity, starch content increased (from 234.5 to 348.5 g/kg), whereas total-tract (99.7 to 94.5%) and ruminal starch digestibility (91.3 to 86.5%) decreased significantly. The decrease in ruminal starch digestibility with increasing maturity was similar between hybrids. No effects were found of maturity, hybrid, or maturity × hybrid interaction on total-tract NDF digestibility, ruminal NDF digestibility, true digestibility of N and organic matter in the rumen, or microbial synthesis. Harvesting at later maturity led to increased ruminal ammonia, total volatile fatty acid concentrations, and acetate/propionate ratio but not pH. This study concludes that delaying date of harvest modifies the proportions of digestible starch and NDF supplied to cattle. Adjusting date of corn harvest to modulate amount of rumen-digested starch could be used as a strategy to control nutrient delivery to ruminants.

  3. Effect of maturity and hybrid on ruminal and intestinal digestion of corn silage in dry cows.

    PubMed

    Peyrat, J; Baumont, R; Le Morvan, A; Nozière, P

    2016-01-01

    The aim of this study was to evaluate the effect of stage of maturity at harvest on extent of starch, neutral detergent fiber (NDF), and protein digestion, and rumen fermentation in dry cows fed whole-plant corn silage from different hybrids. Four nonlactating Holstein cows cannulated at the rumen and proximal duodenum were fed 4 corn silages differing in hybrid (flint vs. flint-dent) and maturity stage (early vs. late) in a 4 × 4 Latin square design. From early to late maturity, starch content increased (from 234.5 to 348.5 g/kg), whereas total-tract (99.7 to 94.5%) and ruminal starch digestibility (91.3 to 86.5%) decreased significantly. The decrease in ruminal starch digestibility with increasing maturity was similar between hybrids. No effects were found of maturity, hybrid, or maturity × hybrid interaction on total-tract NDF digestibility, ruminal NDF digestibility, true digestibility of N and organic matter in the rumen, or microbial synthesis. Harvesting at later maturity led to increased ruminal ammonia, total volatile fatty acid concentrations, and acetate/propionate ratio but not pH. This study concludes that delaying date of harvest modifies the proportions of digestible starch and NDF supplied to cattle. Adjusting date of corn harvest to modulate amount of rumen-digested starch could be used as a strategy to control nutrient delivery to ruminants. PMID:26585483

  4. Digestive enzyme activities in the guts of bonnethead sharks (Sphyrna tiburo) provide insight into their digestive strategy and evidence for microbial digestion in their hindguts.

    PubMed

    Jhaveri, Parth; Papastamatiou, Yannis P; German, Donovan P

    2015-11-01

    Few investigations have studied digestive enzyme activities in the alimentary tracts of sharks to gain insight into how these organisms digest their meals. In this study, we examined the activity levels of proteases, carbohydrases, and lipase in the pancreas, and along the anterior intestine, spiral intestine, and colon of the bonnethead shark, Sphyrna tiburo. We then interpreted our data in the context of a rate-yield continuum to discern this shark's digestive strategy. Our data show anticipated decreasing patterns in the activities of pancreatic enzymes moving posteriorly along the gut, but also show mid spiral intestine peaks in aminopeptidase and lipase activities, which support the spiral intestine as the main site of absorption in bonnetheads. Interestingly, we observed spikes in the activity levels of N-acetyl-β-D-glucosaminidase and β-glucosidase in the bonnethead colon, and these chitin- and cellulose-degrading enzymes, respectively, are likely of microbial origin in this distal gut region. Taken in the context of intake and relatively long transit times of food through the gut, the colonic spikes in N-acetyl-β-D-glucosaminidase and β-glucosidase activities suggest that bonnetheads take a yield-maximizing strategy to the digestive process, with some reliance on microbial digestion in their hindguts. This is one of the first studies to examine digestive enzyme activities along the gut of any shark, and importantly, the data match with previous observations that sharks take an extended time to digest their meals (consistent with a yield-maximizing digestive strategy) and that the spiral intestine is the primary site of absorption in sharks.

  5. Digestive enzyme activities in the guts of bonnethead sharks (Sphyrna tiburo) provide insight into their digestive strategy and evidence for microbial digestion in their hindguts.

    PubMed

    Jhaveri, Parth; Papastamatiou, Yannis P; German, Donovan P

    2015-11-01

    Few investigations have studied digestive enzyme activities in the alimentary tracts of sharks to gain insight into how these organisms digest their meals. In this study, we examined the activity levels of proteases, carbohydrases, and lipase in the pancreas, and along the anterior intestine, spiral intestine, and colon of the bonnethead shark, Sphyrna tiburo. We then interpreted our data in the context of a rate-yield continuum to discern this shark's digestive strategy. Our data show anticipated decreasing patterns in the activities of pancreatic enzymes moving posteriorly along the gut, but also show mid spiral intestine peaks in aminopeptidase and lipase activities, which support the spiral intestine as the main site of absorption in bonnetheads. Interestingly, we observed spikes in the activity levels of N-acetyl-β-D-glucosaminidase and β-glucosidase in the bonnethead colon, and these chitin- and cellulose-degrading enzymes, respectively, are likely of microbial origin in this distal gut region. Taken in the context of intake and relatively long transit times of food through the gut, the colonic spikes in N-acetyl-β-D-glucosaminidase and β-glucosidase activities suggest that bonnetheads take a yield-maximizing strategy to the digestive process, with some reliance on microbial digestion in their hindguts. This is one of the first studies to examine digestive enzyme activities along the gut of any shark, and importantly, the data match with previous observations that sharks take an extended time to digest their meals (consistent with a yield-maximizing digestive strategy) and that the spiral intestine is the primary site of absorption in sharks. PMID:26239220

  6. Steam Digest: Volume IV

    SciTech Connect

    Not Available

    2004-07-01

    This edition of the Steam Digest is a compendium of 2003 articles on the technical and financial benefits of steam efficiency, presented by the stakeholders of the U.S. Department of Energy's BestPractices Steam effort.

  7. Steam Digest 2001

    SciTech Connect

    Not Available

    2002-01-01

    Steam Digest 2001 chronicles BestPractices Program's contributions to the industrial trade press for 2001, and presents articles that cover technical, financial and managerial aspects of steam optimization.

  8. Steam Digest Volume IV

    SciTech Connect

    2004-07-01

    This edition of the Steam Digest is a compendium of 2003 articles on the technical and financial benefits of steam efficiency, presented by the stakeholders of the U.S. Department of Energy's BestPractices Steam effort.

  9. Portuguese Primary School Children's Conceptions about Digestion: Identification of Learning Obstacles. Research Report

    ERIC Educational Resources Information Center

    Carvalho, Graca; Silva, Rui; Lima, Nelson; Coquet, Eduarda; Clement, Pierre

    2004-01-01

    A cross-sectional study of Portuguese primary school pupils' conceptions on digestion and the digestive tract was carried out before and after teaching this topic. Pupils of the prior four school years (5/6 to 9/10 year old) drew what happens to a cookie inside their body. In some cases they also wrote a short text or were interviewed. To identify…

  10. Histopathologic diagnosis of eosinophilic conditions in the gastrointestinal tract.

    PubMed

    Hurrell, Jennifer M; Genta, Robert M; Melton, Shelby D

    2011-09-01

    Eosinophils, a constitutive component of the columnar-lined gastrointestinal tract, play an essential role in allergic responses and parasitic infections. The tissue density of these cells also increases in a variety of conditions of uncertain etiology. With the exception of the esophageal squamous epithelium, in which no eosinophils are normally present, the population of normal eosinophils in the remainder of the luminal gut is poorly defined. Therefore, histopathologists must rely on their subjective judgment to determine when a diagnosis of eosinophilic gastritis, enteritis, or colitis should be rendered. Eosinophilic esophagitis is currently the best defined and most studied eosinophilic condition of the digestive tract; therefore, the confidence in accurate diagnosis is increasing. In contrast, the characteristic clinicopathologic features of eosinophilic conditions affecting other parts of the digestive tract remain somewhat elusive. This review was designed to present pathologists with simple and practical information for the biopsy-based histopathologic diagnosis of eosinophilic esophagitis, gastritis, enteritis, and colitis. It was prepared by critically reviewing more than 200 articles on the topic, along with incorporating evidence accumulated through our own collective experience. We anticipate that by increasing pathologists' confidence in reporting these abnormal but often nameless eosinophilic infiltrates, we can help better define and characterize their significance. PMID:21841404

  11. The sense of taste in the upper gastrointestinal tract.

    PubMed

    Kitamura, Akihiko; Tsurugizawa, Tomokazu; Uematsu, Akira; Uneyama, Hisayuki

    2014-01-01

    Digestion and the absorption of food and nutrients have been considered the only functions of the gastrointestinal (GI) tract. However, recent studies suggest that taste cells in the oral cavity and taste-like cells in the GI tract share many common characteristics (taste receptors and transduction signaling). Over the last two decades, it has been revealed that the GI tract is a chemosensory organ that transfers nutrient information via GI hormone secretion (glucagon-like peptide-1, Peptide YY, oxyntomodulin, glucose-dependent insulinotropic polypeptide and others) and the activation of abdominal vagus afferents. In addition, the information relayed via the abdominal vagus nerve plays an important role in autonomic reflexes. This information, both humoral and neural, contributes to the maintenance of homeostasis (digestion, absorption, metabolism and food intake) in the body. In this review, we provide a brief overview of the following: GI chemosensory molecules, their distribution, the effect of nutrients on GI hormone secretion and the activation of vagus afferent nerves. We also focus on the possibility of clinical applications that control abdominal vagus activity.

  12. Development of a simple model device for in vitro gastric digestion investigation.

    PubMed

    Chen, Jianshe; Gaikwad, Vishwajeet; Holmes, Melvin; Murray, Brent; Povey, Malcolm; Wang, Ye; Zhang, Ying

    2011-04-01

    There have been some reports in the literature of model gastric digestion systems to mimic the dynamic physiological processes within the gastrointestinal tract. However, such devices often require the specification of many control parameters making routine digestion tests unfeasible. This paper introduces a simple in vitro digestion device, comprising of a water-jacketed glass vessel into which a spherical Teflon probe of variable diameter can be inserted. The probe is controlled by a texture analyser to simulate the kinetics of a food digestion process. Using this device under well controlled hydrodynamic flow and biochemical conditions key digestion parameters such as pH, food particle size, protein release, lipid release, cloudiness, etc, can be determined. Feasibility tests of the model device have been conducted using roasted and non-roasted peanuts particles. The status of peanut digestion was examined by the changes in particle size distribution and the mean particle size. Significant differences of surface microstructure have also been observed for peanut particles after the digestion. The influence of parameters such as food to gastric juice ratio, the probe speed and pepsin concentration have been examined in this work. Initial results confirm that all these factors influence the kinetic process of gastric digestion considerably and should be well regulated in any in vitro digestion investigations. We propose that the model device has the advantages of easy control and operation and furthermore could be an ideal tool for routine in vitro gastric digestion studies. PMID:21779576

  13. Neonatal Staphylococcus lugdunensis urinary tract infection.

    PubMed

    Hayakawa, Itaru; Hataya, Hiroshi; Yamanouchi, Hanako; Sakakibara, Hiroshi; Terakawa, Toshiro

    2015-08-01

    Staphylococcus lugdunensis is a known pathogen of infective endocarditis, but not of urinary tract infection. We report a previously healthy neonate without congenital anomalies of the kidney and urinary tract who developed urinary tract infection due to Staphylococcus lugdunensis, illustrating that Staphylococcus lugdunensis can cause urinary tract infection even in those with no urinary tract complications. PMID:26177232

  14. Urinary Tract Endometriosis.

    PubMed

    Kołodziej, Anna; Krajewski, Wojciech; Dołowy, Łukasz; Hirnle, Lidia

    2015-01-01

    Recently, occurrence of urinary tract endometriosis (UTE) is more frequently diagnosed. According to literature, it refers to approximately 0.3 to even 12% of all women with endometriosis. The pathogenesis of UTE has not been clearly explained so far. The actually proposed hypotheses include embryonic, migration, transplantation, and iatrogenic theory. Most frequently UTE affects bladder, less often ureters and kidneys. One-third of patients remains asymptomatic or exhibits only minor manifestations. In symptomatic patients main complaints include dysuria, urinary urgency, and/or frequency, painful micturition, and burning sensation in the urethra and discomfort in the retropubic area. Treatment of UTE is challenging and can be pharmacological, surgical or can be a combination of both methods. In this paper we present a review of the literature concerning the UTE, its diagnosis and treatment. PMID:26341760

  15. Ingestible wireless capsules for enhanced diagnostic inspection of gastrointestinal tract

    NASA Astrophysics Data System (ADS)

    Rasouli, Mahdi; Kencana, Andy Prima; Huynh, Van An; Ting, Eng Kiat; Lai, Joshua Chong Yue; Wong, Kai Juan; Tan, Su Lim; Phee, Soo Jay

    2011-03-01

    Wireless capsule endoscopy has become a common procedure for diagnostic inspection of gastrointestinal tract. This method offers a less-invasive alternative to traditional endoscopy by eliminating uncomfortable procedures of the traditional endoscopy. Moreover, it provides the opportunity for exploring inaccessible areas of the small intestine. Current capsule endoscopes, however, move by peristalsis and are not capable of detailed and on-demand inspection of desired locations. Here, we propose and develop two wireless endoscopes with maneuverable vision systems to enhance diagnosis of gastrointestinal disorders. The vision systems in these capsules are equipped with mechanical actuators to adjust the position of the camera. This may help to cover larger areas of the digestive tract and investigate desired locations. The preliminary experimental results showed that the developed platform could successfully communicate with the external control unit via human body and adjust the position of camera to limited degrees.

  16. Cellular Organization of Neuroimmune Interactions in the Gastrointestinal Tract

    PubMed Central

    Margolis, Kara Gross; Gershon, Michael David; Bogunovic, Milena

    2016-01-01

    The gastrointestinal (GI) tract is the largest immune organ; in vertebrates, it is the only organ whose function is controlled by its own intrinsic enteric nervous system (ENS), but it is additionally regulated by extrinsic (sympathetic and parasympathetic) innervation. The GI nervous and immune systems are highly integrated in their common goal, which is to unite digestive functions with protection from ingested environmental threats. This review discusses the physiological relevance of enteric neuroimmune integration by summarizing the current knowledge of evolutionary and developmental pathways, cellular organization, and molecular mechanisms of neuroimmune interactions in health and disease. PMID:27289177

  17. Development and Validation of a New Blade Element Momentum Skewed-Wake Model within AeroDyn: Preprint

    SciTech Connect

    Ning, S. A.; Hayman, G.; Damiani, R.; Jonkman, J.

    2014-12-01

    Blade element momentum methods, though conceptually simple, are highly useful for analyzing wind turbines aerodynamics and are widely used in many design and analysis applications. A new version of AeroDyn is being developed to take advantage of new robust solution methodologies, conform to a new modularization framework for National Renewable Energy Laboratory's FAST, utilize advanced skewed-wake analysis methods, fix limitations with previous implementations, and to enable modeling of highly flexible and nonstraight blades. This paper reviews blade element momentum theory and several of the options available for analyzing skewed inflow. AeroDyn implementation details are described for the benefit of users and developers. These new options are compared to solutions from the previous version of AeroDyn and to experimental data. Finally, recommendations are given on how one might select from the various available solution approaches.

  18. The spectral analysis of an aero-engine assembly incorporating a squeeze-film damper

    NASA Technical Reports Server (NTRS)

    Holmes, R.; Dede, M. M.

    1989-01-01

    Aero-engine structures have very low inherent damping and so artificial damping is often introduced by pumping oil into annular gaps between the casings and the outer races of some or all of the rolling-element bearings supporting the rotors. The thin oil films so formed are called squeeze film dampers and they can be beneficial in reducing rotor vibration due to unbalance and keeping to reasonable limits the forces transmitted to the engine casing. However, squeeze-film dampers are notoriously non-linear and as a result can introduce into the assembly such phenomena as subharmonic oscillations, jumps and combination frequencies. The purpose of the research is to investigate such phenomena both theoretically and experimentally on a test facility reproducing the essential features of a medium-size aero engine. The forerunner of this work was published. It was concerned with the examination of a squeeze-film damper in series with housing flexibility when supporting a rotor. The structure represented to a limited extent the essentials of the projected Rolls Royce RB401 engine. That research demonstrated the ability to calculate the oil-film forces arising from the squeeze film from known motions of the bearing components and showed that the dynamics of a shaft fitted with a squeeze film bearing can be predicted reasonably accurately. An aero-engine will normally have at least two shafts and so in addition to the excitation forces which are synchronous with the rotation of one shaft, there will also be forces at other frequencies from other shafts operating on the squeeze-film damper. Theoretical and experimental work to consider severe loading of squeeze-film dampers and to include these additional effects are examined.

  19. AeroCom INSITU Project: Comparing modeled and measured aerosol optical properties

    NASA Astrophysics Data System (ADS)

    Andrews, Elisabeth; Schmeisser, Lauren; Schulz, Michael; Fiebig, Markus; Ogren, John; Bian, Huisheng; Chin, Mian; Easter, Richard; Ghan, Steve; Kokkola, Harri; Laakso, Anton; Myhre, Gunnar; Randles, Cynthia; da Silva, Arlindo; Stier, Phillip; Skeie, Ragnehild; Takemura, Toshihiko; van Noije, Twan; Zhang, Kai

    2016-04-01

    AeroCom, an open international collaboration of scientists seeking to improve global aerosol models, recently initiated a project comparing model output to in-situ, surface-based measurements of aerosol optical properties. The model/measurement comparison project, called INSITU, aims to evaluate the performance of a suite of AeroCom aerosol models with site-specific observational data in order to inform iterative improvements to model aerosol modules. Surface in-situ data has the unique property of being traceable to physical standards, which is an asset in accomplishing the overall goal of bettering the accuracy of aerosols processes and the predicative capability of global climate models. Here we compare dry, in-situ aerosol scattering and absorption data from ~75 surface, in-situ sites from various global aerosol networks (including NOAA, EUSAAR/ACTRIS and GAW) with a simulated optical properties from a suite of models participating in the AeroCom project. We report how well models reproduce aerosol climatologies for a variety of time scales, aerosol characteristics and behaviors (e.g., aerosol persistence and the systematic relationships between aerosol optical properties), and aerosol trends. Though INSITU is a multi-year endeavor, preliminary phases of the analysis suggest substantial model biases in absorption and scattering coefficients compared to surface measurements, though the sign and magnitude of the bias varies with location. Spatial patterns in the biases highlight model weaknesses, e.g., the inability of models to properly simulate aerosol characteristics at sites with complex topography. Additionally, differences in modeled and measured systematic variability of aerosol optical properties suggest that some models are not accurately capturing specific aerosol behaviors, for example, the tendency of in-situ single scattering albedo to decrease with decreasing aerosol extinction coefficient. The endgoal of the INSITU project is to identify specific

  20. Aero-servo-viscoelasticity theory: Lifting surfaces, plates, velocity transients, flutter, and instability

    NASA Astrophysics Data System (ADS)

    Merrett, Craig G.

    Modern flight vehicles are fabricated from composite materials resulting in flexible structures that behave differently from the more traditional elastic metal structures. Composite materials offer a number of advantages compared to metals, such as improved strength to mass ratio, and intentional material property anisotropy. Flexible aircraft structures date from the Wright brothers' first aircraft with fabric covered wooden frames. The flexibility of the structure was used to warp the lifting surface for flight control, a concept that has reappeared as aircraft morphing. These early structures occasionally exhibited undesirable characteristics during flight such as interactions between the empennage and the aft fuselage, or control problems with the elevators. The research to discover the cause and correction of these undesirable characteristics formed the first foray into the field of aeroelasticity. Aeroelasticity is the intersection and interaction between aerodynamics, elasticity, and inertia or dynamics. Aeroelasticity is well suited for metal aircraft, but requires expansion to improve its applicability to composite vehicles. The first is a change from elasticity to viscoelasticity to more accurately capture the solid mechanics of the composite material. The second change is to include control systems. While the inclusion of control systems in aeroelasticity lead to aero-servo-elasticity, more control possibilities exist for a viscoelastic composite material. As an example, during the lay-up of carbon-epoxy plies, piezoelectric control patches are inserted between different plies to give a variety of control options. The expanded field is called aero-servo-viscoelasticity. The phenomena of interest in aero-servo-viscoelasticity are best classified according to the type of structure considered, either a lifting surface or a panel, and the type of dynamic stability present. For both types of structures, the governing equations are integral

  1. Radiative forcing of the direct aerosol effect from AeroCom Phase II simulations

    SciTech Connect

    Myhre, G.; Samset, B. H.; Schulz, M.; Balkanski, Y.; Bauer, S.; Berntsen, T. K.; Bian, H.; Bellouin, N.; Chin, M.; Diehl, T.; Easter, R. C.; Feichter, J.; Ghan, S. J.; Hauglustaine, D.; Iversen, T.; Kinne, S.; Kirkevåg, A.; Lamarque, J. -F.; Lin, G.; Liu, X.; Lund, M. T.; Luo, G.; Ma, X.; van Noije, T.; Penner, J. E.; Rasch, P. J.; Ruiz, A.; Seland, Ø.; Skeie, R. B.; Stier, P.; Takemura, T.; Tsigaridis, K.; Wang, P.; Wang, Z.; Xu, L.; Yu, H.; Yu, F.; Yoon, J. -H.; Zhang, K.; Zhang, H.; Zhou, C.

    2013-01-01

    We report on the AeroCom Phase II direct aerosol effect (DAE) experiment where 16 detailed global aerosol models have been used to simulate the changes in the aerosol distribution over the industrial era. All 16 models have estimated the radiative forcing (RF) of the anthropogenic DAE, and have taken into account anthropogenic sulphate, black carbon (BC) and organic aerosols (OA) from fossil fuel, biofuel, and biomass burning emissions. In addition several models have simulated the DAE of anthropogenic nitrate and anthropogenic influenced secondary organic aerosols (SOA). The model simulated all-sky RF of the DAE from total anthropogenic aerosols has a range from -0.58 to -0.02 Wm-2, with a mean of -0.27 Wm-2 for the 16 models. Several models did not include nitrate or SOA and modifying the estimate by accounting for this with information from the other AeroCom models reduces the range and slightly strengthens the mean. Modifying the model estimates for missing aerosol components and for the time period 1750 to 2010 results in a mean RF for the DAE of -0.35 Wm-2. Compared to AeroCom Phase I (Schulz et al., 2006) we find very similar spreads in both total DAE and aerosol component RF. However, the RF of the total DAE is stronger negative and RF from BC from fossil fuel and biofuel emissions are stronger positive in the present study than in the previous AeroCom study. We find a tendency for models having a strong (positive) BC RF to also have strong (negative) sulphate or OA RF. This relationship leads to smaller uncertainty in the total RF of the DAE compared to the RF of the sum of the individual aerosol components. The spread in results for the individual aerosol components is substantial, and can be divided into diversities in burden, mass extinction coefficient (MEC), and normalized RF with respect to AOD. We find that these three factors give similar contributions to the spread in results.

  2. The Brief Introduction of Different Laser Diagnostics Methods Used in Aero-Engine Combustion Research

    NASA Astrophysics Data System (ADS)

    Xing, Fei; Song, Ge; Ruan, Can; Zhao, Jian; Yang, Yongjun

    2016-06-01

    Combustion test diagnose has always been one of the most important technologies for the development of aerospace engineering. Laser diagnostics techniques developed quickly in the past several years. They are used to measure the parameters of the combustion flow field such as velocity, temperature, components concentration with high space and time resolution and brought no disturbance. Planar Laser-Induced Fluorescence, Coherent Anti-Stokes Raman Scattering, Tunable Diode Laser Absorption Spectroscopy and Raman Scattering were introduced systemically in this paper. After analysis their own advantages and disadvantages, it is believed that Raman Scattering system is more suitable for research activities on aero-engine combustion systems.

  3. Applications of aero-acoustics to wind turbine noise prediction and control

    NASA Astrophysics Data System (ADS)

    Lowson, Martin V.

    1993-01-01

    Wind turbine noise generation mechanisms are essentially equivalent to the aero-acoustic mechanisms of other rotors, which have been studied in depth for many years. Basic sources for the wind turbine noise radiation process are defined, and their significance assessed. From the analysis, areas of potential improvement in wind turbine noise prediction are defined. Suggestions are made for approaches to wind turbine noise control which separate the noise problems at cut-in from those at rated power. Some of these offer the possibility of noise reduction without unfavourable effects on performance.

  4. Fractional Order Modeling of Atmospheric Turbulence - A More Accurate Modeling Methodology for Aero Vehicles

    NASA Technical Reports Server (NTRS)

    Kopasakis, George

    2014-01-01

    The presentation covers a recently developed methodology to model atmospheric turbulence as disturbances for aero vehicle gust loads and for controls development like flutter and inlet shock position. The approach models atmospheric turbulence in their natural fractional order form, which provides for more accuracy compared to traditional methods like the Dryden model, especially for high speed vehicle. The presentation provides a historical background on atmospheric turbulence modeling and the approaches utilized for air vehicles. This is followed by the motivation and the methodology utilized to develop the atmospheric turbulence fractional order modeling approach. Some examples covering the application of this method are also provided, followed by concluding remarks.

  5. Aeronautical Satellite-Assisted Process for Information Exchange Through Network Technologies (Aero-SAPIENT) Conducted

    NASA Technical Reports Server (NTRS)

    Zernic, Michael J.

    2002-01-01

    Broadband satellite communications for aeronautics marries communication and network technologies to address NASA's goals in information technology base research and development, thereby serving the safety and capacity needs of the National Airspace System. This marriage of technology increases the interactivity between airborne vehicles and ground systems. It improves decision-making and efficiency, reduces operation costs, and improves the safety and capacity of the National Airspace System. To this end, a collaborative project called the Aeronautical Satellite Assisted Process for Information Exchange through Network Technologies, or Aero-SAPIENT, was conducted out of Tinker AFB, Oklahoma, during November and December 2000.

  6. AeroPropulsoServoElasticity: Dynamic Modeling of the Variable Cycle Propulsion System

    NASA Technical Reports Server (NTRS)

    Kopasakis, George

    2012-01-01

    This presentation was made at the 2012 Fundamental Aeronautics Program Technical Conference and it covers research work for the Dynamic Modeling of the Variable cycle Propulsion System that was done under the Supersonics Project, in the area of AeroPropulsoServoElasticity. The presentation covers the objective for the propulsion system dynamic modeling work, followed by the work that has been done so far to model the variable Cycle Engine, modeling of the inlet, the nozzle, the modeling that has been done to model the affects of flow distortion, and finally presenting some concluding remarks and future plans.

  7. Structured grid generation using a CAD solid model for an aero-gas turbine combustion system

    SciTech Connect

    Eccles, N.C.; Manners, A.P.

    1996-12-31

    An aero-gas turbine combustion system was used to demonstrate the problems of creating a single block structured grid suitable for CFD predictions from a designer`s parametric solid model. The solid model had to be filtered of sub-grid detail and computational fluid volumes generated from the solid model of the metal. Alternative methods of transferring the geometry from the CAD package to the grid generator were considered. The type and method of grid generation was found to influence all stages in manipulating the geometry.

  8. Optical key distribution based on aero-optical effect of boundary layer flow

    NASA Astrophysics Data System (ADS)

    Wu, Xu; Wu, Kenan; Liu, Chao

    2014-07-01

    An optical key distribution method based on aero-optical effect of boundary layer flow is proposed. The technique exploits the underlying dynamics of the turbulence boundary layer to generate secret key for both communication parties. Corresponding computer simulation and experiments are carried out. The bit error rate of key distribution is 0.05% and 0.22% in the simulation and the experiment, respectively. Further test also shows that the proposed key generation technique is valid to work with optical encryption technique.

  9. Genotype by environment interaction effects on starch content and digestibility in potato (Solanum tuberosum L.).

    PubMed

    Bach, Stephanie; Yada, Rickey Y; Bizimungu, Benoit; Fan, Ming; Sullivan, J Alan

    2013-04-24

    Biochemically, starch is composed of amylose and amylopectin but can also be defined by its digestibility rates within the human intestinal tract, i.e., rapidly digested (RDS), slowly digested (SDS), or resistant (RS). The relative ratio of these starch components is the main contributor to differences in the glycemic index (GI) of carbohydrate sources. This study evaluated the digestible starch profile of 12 potato genotypes comprising elite breeding lines and commercial varieties in six environments, with the optimal profile defined as low RDS and high SDS. Genotype by environment interaction (GEI) analysis found significant (p = 0.05) genotypic and environmental effects for all digestibility rate components; however, interaction effects were only significant for SDS. Optimal starch profiles were identified for two genotypes, CV96044-3 and Goldrush. The desirable starch profile in these potato cultivars can be exploited in breeding programs for the improvement of starch profile and other important characteristics such as high yields and disease resistance.

  10. Optimal digestion theory does not predict the effect of pathogens on intestinal plasticity

    PubMed Central

    Venesky, Matthew D.; Hanlon, Shane M.; Lynch, Kyle; Parris, Matthew J.; Rohr, Jason R.

    2013-01-01

    One prediction of optimal digestion theory is that organisms will increase the relative length of their digestive tracts when food resources become limited. We used theory of optimal digestion to test whether tadpoles can adjust the relative length of their intestines when challenged with the fungal pathogen Batrachochytrium dendrobatidis (Bd). The degree of tadpole mouthpart damage, a symptom of Bd infections that reduces food consumption, was associated positively with the length of tadpole intestines relative to their body size, consistent with optimal digestion theory. After controlling for mouthpart damage, tadpoles exposed to Bd had shorter intestines relative to their body size, opposite to the predictions of optimal digestion theory. One explanation of why tadpoles with higher Bd loads have shorter relative intestinal lengths is that they divert energy from maintaining intestinal and overall growth towards anti-parasite defences. PMID:23445950

  11. Aero Spacelines B377PG Pregnant Guppy on ramp in preparation for flight tests and pilot evaluation

    NASA Technical Reports Server (NTRS)

    1962-01-01

    The Aero Spacelines B377PG Pregnant Guppy was flown by Aero Spacelines pilots to Dryden for tests and evaluation by pilots Joe Vensel and Stan Butchart in October 1962. The outsized cargo aircraft incorporated the wings, engines, lower fuselage and tail from a Boeing 377 Stratocruiser with a huge upper fuselage more than 20 feet in diameter. The modified aircraft was built to transport outsized cargo for NASA's Apollo program, primarily to carry portions of the Saturn V rockets from the manufacturer to Cape Canaveral. Later versions of the aircraft, including the Super Guppy and the Super Guppy Turbine, are still in use.

  12. Cardiac outflow tract anomalies

    PubMed Central

    Neeb, Zachary; Lajiness, Jacquelyn D.; Bolanis, Esther; Conway, Simon J

    2014-01-01

    The mature outflow tract (OFT) is, in basic terms, a short conduit. It is a simple, although vital, connection situated between contracting muscular heart chambers and a vast embryonic vascular network. Unfortunately, it is also a focal point underlying many multifactorial congenital heart defects (CHDs). Through the use of various animal models combined with human genetic investigations, we are beginning to comprehend the molecular and cellular framework that controls OFT morphogenesis. Clear roles of neural crest cells (NCC) and second heart field (SHF) derivatives have been established during OFT formation and remodeling. The challenge now is to determine how the SHF and cardiac NCC interact, the complex reciprocal signaling that appears to be occurring at various stages of OFT morphogenesis, and finally how endocardial progenitors and primary heart field (PHF) communicate with both these colonizing extra-cardiac lineages. Although we are beginning to understand that this dance of progenitor populations is wonderfully intricate, the underlying pathogenesis and the spatiotemporal cell lineage interactions remain to be fully elucidated. What is now clear is that OFT alignment and septation are independent processes, invested via separate SHF and cardiac neural crest (CNC) lineages. This review will focus on our current understanding of the respective contributions of the SHF and CNC lineage during OFT development and pathogenesis. PMID:24014420

  13. The effect of replacing lactose by starch on protein and fat digestion in milk-fed veal calves.

    PubMed

    Pluschke, A M; Gilbert, M S; Williams, B A; van den Borne, J J G C; Schols, H A; Gerrits, W J J

    2016-08-01

    Replacing dairy components from milk replacer (MR) with vegetable products has been previously associated with decreased protein and fat digestibility in milk-fed calves resulting in lower live weight gain. In this experiment, the major carbohydrate source in MR, lactose, was partly replaced with gelatinized corn starch (GCS) to determine the effect on protein and fat digestibility in milk-fed calves. In total, 16 male Holstein-Friesian calves received either MR with lactose as the carbohydrate source (control) or 18% GCS at the expense of lactose. In the adaptation period, calves were exposed to an increasing dose of GCS for 14 weeks. The indigestible marker cobalt ethylenediaminetetraacetic acid was incorporated into the MR for calculating apparent nutrient digestibility, whereas a pulse dose of chromium (Cr) chloride was fed with the last MR meal 4 h before slaughter as an indicator of passage rates. The calves were anesthetized and exsanguinated at 30 weeks of age. The small intestine was divided in three; small intestine 1 and 2 (SI1 and SI2, respectively) and the terminal ileum (last ~100 cm of small intestine) and samples of digesta were collected. Small intestinal digesta was analysed for α-amylase, lipase and trypsin activity. Digestibility of protein was determined for SI1, SI2, ileum and total tract, whereas digestibility of fat was determined for SI1, SI2 and total tract. Apparent protein digestibility in the small intestine did not differ between treatments but was higher in control calves at total tract level. Apparent crude fat digestibility tended to be increased in SI1 and SI2 for GCS calves, but no difference was found at total tract level. Activity of α-amylase in SI2 and lipase in both SI1 and SI2 was higher in GCS calves. Activity of trypsin tended to be higher in control calves and was higher in SI1 compared with SI2. A lower recovery of Cr in SI2 and a higher recovery of Cr in the large intestine suggest an increased rate of passage for GCS

  14. Lipid digestibility and energy content of distillers corn oil in swine and poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two experiments were conducted to determine the DE and ME, and apparent total tract digestibility of ether extract of 3 distillers corn oil (DCO; 4.9, 12.8, or 13.9% FFA), compared with a sample of refined corn oil (CO, 0.04% FFA), and an industrially-hydrolyzed high FFA DCO (93.8% FFA) in young pig...

  15. 78 FR 7793 - National Institute of Diabetes and Digestive and Kidney Diseases; Notice of Closed Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-04

    ... HUMAN SERVICES National Institutes of Health National Institute of Diabetes and Digestive and Kidney... Kidney Diseases Special Emphasis Panel; Program Project on Differentiation of GI Tract. Date: April 3... Research; 93.849, Kidney Diseases, Urology and Hematology Research, National Institutes of Health,...

  16. An enzyme complex increases in vitro dry matter digestibility of corn and wheat in pigs.

    PubMed

    Park, Kyu Ree; Park, Chan Sol; Kim, Beob Gyun

    2016-01-01

    Two experiments were conducted to determine the effects of enzyme complex on in vitro dry matter (DM) digestibility for feed ingredients. The objective of experiment 1 was to screen feed ingredients that can be effective substrates for an enzyme complex, mainly consisted of β-pentosanase, β-glucanase and α-amylase, using in vitro digestibility methods. In experiment 1, the test ingredients were three grain sources (barley, corn and wheat) and six protein supplements (canola meal, copra expellers, cottonseed meal, distillers dried grains with solubles, palm kernel expellers and soybean meal). In vitro ileal and total tract digestibility (IVID and IVTTD, respectively) of DM for test ingredients were determined. In vitro digestibility methods consisted of two- or three-step procedure simulating in vivo digestion in the pig gastrointestinal tracts with or without enzyme complex. As the enzyme complex added, the IVID of DM for corn and wheat increased (p < 0.05) by 5.0 and 2.6 percentage unit, respectively. The IVTTD of DM for corn increased (p < 0.05) by 3.1 percentage unit with enzyme complex addition. As the effect of enzyme complex was the greatest in corn digestibility, corn grains were selected to determine the in vitro digestibility of the fractions (starch, germ, hull and gluten) that maximally respond to the enzyme complex in experiment 2. The IVID of DM for corn starch, germ and hull increased (p < 0.05) by 16.0, 2.8 and 1.2 percentage unit, respectively. The IVTTD of DM for corn starch and hull also increased (p < 0.05) by 8.6 and 0.9 percentage unit, respectively, with enzyme complex addition. In conclusion, the enzyme complex increases in vitro DM digestibility of corn and wheat, and the digestibility increments of corn are mainly attributed to the increased digestibility of corn starch.

  17. An enzyme complex increases in vitro dry matter digestibility of corn and wheat in pigs.

    PubMed

    Park, Kyu Ree; Park, Chan Sol; Kim, Beob Gyun

    2016-01-01

    Two experiments were conducted to determine the effects of enzyme complex on in vitro dry matter (DM) digestibility for feed ingredients. The objective of experiment 1 was to screen feed ingredients that can be effective substrates for an enzyme complex, mainly consisted of β-pentosanase, β-glucanase and α-amylase, using in vitro digestibility methods. In experiment 1, the test ingredients were three grain sources (barley, corn and wheat) and six protein supplements (canola meal, copra expellers, cottonseed meal, distillers dried grains with solubles, palm kernel expellers and soybean meal). In vitro ileal and total tract digestibility (IVID and IVTTD, respectively) of DM for test ingredients were determined. In vitro digestibility methods consisted of two- or three-step procedure simulating in vivo digestion in the pig gastrointestinal tracts with or without enzyme complex. As the enzyme complex added, the IVID of DM for corn and wheat increased (p < 0.05) by 5.0 and 2.6 percentage unit, respectively. The IVTTD of DM for corn increased (p < 0.05) by 3.1 percentage unit with enzyme complex addition. As the effect of enzyme complex was the greatest in corn digestibility, corn grains were selected to determine the in vitro digestibility of the fractions (starch, germ, hull and gluten) that maximally respond to the enzyme complex in experiment 2. The IVID of DM for corn starch, germ and hull increased (p < 0.05) by 16.0, 2.8 and 1.2 percentage unit, respectively. The IVTTD of DM for corn starch and hull also increased (p < 0.05) by 8.6 and 0.9 percentage unit, respectively, with enzyme complex addition. In conclusion, the enzyme complex increases in vitro DM digestibility of corn and wheat, and the digestibility increments of corn are mainly attributed to the increased digestibility of corn starch. PMID:27247894

  18. Congenital diseases of the gastrointestinal tract.

    PubMed

    Lentze, M

    2014-05-01

    With the rapid increase in knowledge on the genetic origin of diseases within the gastrointestinal tract the number of congenital diseases, which already manifest during childhood have drastically increased. Due to the large application of molecular genetics the number is steadily increasing. To make the access to these rare diseases fast and efficient the data base of the National Library of Medicine (Online Mendelian Inheritance of Man - OMIN) is a very helpful online tool, with which all these disease entities can be found easily (http://www.ncbi.nlm.nih.gov/omim). Detailed tables are given to find most of the congenitally inherited disease, which affect the gastrointestinal tract. A variety of congenital diarrheas with disturbances of digestion, hydrolysis, absorption and secretion is described in detail: lactose intolerance, sucrose intolerance, glucose-galactose malabsorption, fructose malabsorption, trehalase and enterokinase deficiency, congenital chloride and sodium diarrhea, congenital hypomagnesaemia, primary bile acid malabsorption, acrodermatitis enteropathica and Menke's syndrome. Also described in detail are diseases with structural anomalies of the intestine like microvillous inclusion disease, congenital tufting enteropathy and IPEX syndrome. The diagnosis in the disturbances of carbohydrate hydrolysis or absorption can be established by H2-breath tests after appropriate sugar challenge. Treatment consists of elimination of the responsible sugar from the diet. The diagnosis of the congenital secretory diarrheas is established by investigation of electrolytes in blood and stool. Substitution of high doses of the responsible mineral can improve the clinical outcome. In acrodermatitis enteropathica low serum zinc level together with the typical skin lesions guide to the diagnosis. High doses of oral zinc aspartate can cure the symptoms of the disease. The diagnosis of structural congenital lesions of the intestine can be established by histology and

  19. Dietary Proteins as Determinants of Metabolic and Physiologic Functions of the Gastrointestinal Tract

    PubMed Central

    Jahan-Mihan, Alireza; Luhovyy, Bohdan L.; Khoury, Dalia El; Anderson, G. Harvey

    2011-01-01

    Dietary proteins elicit a wide range of nutritional and biological functions. Beyond their nutritional role as the source of amino acids for protein synthesis, they are instrumental in the regulation of food intake, glucose and lipid metabolism, blood pressure, bone metabolism and immune function. The interaction of dietary proteins and their products of digestion with the regulatory functions of the gastrointestinal (GI) tract plays a dominant role in determining the physiological properties of proteins. The site of interaction is widespread, from the oral cavity to the colon. The characteristics of proteins that influence their interaction with the GI tract in a source-dependent manner include their physico-chemical properties, their amino acid composition and sequence, their bioactive peptides, their digestion kinetics and also the non-protein bioactive components conjugated with them. Within the GI tract, these products affect several regulatory functions by interacting with receptors releasing hormones, affecting stomach emptying and GI transport and absorption, transmitting neural signals to the brain, and modifying the microflora. This review discusses the interaction of dietary proteins during digestion and absorption with the physiological and metabolic functions of the GI tract, and illustrates the importance of this interaction in the regulation of amino acid, glucose, lipid metabolism, and food intake. PMID:22254112

  20. Effects of Aging on the Digestive System

    MedlinePlus

    ... Mail Facebook TwitterTitle Google+ LinkedIn Home Digestive Disorders Biology of the Digestive System Effects of Aging on ... Version. DOCTORS: Click here for the Professional Version Biology of the Digestive System Overview of the Digestive ...

  1. Stability of food allergens to digestion in vitro.

    PubMed

    Astwood, J D; Leach, J N; Fuchs, R L

    1996-10-01

    An integral part of the safety assessment of genetically modified plants is consideration of possible human health effects, especially food allergy. Prospective testing for allergenicity of proteins obtained from sources with no prior history of causing allergy has been difficult because of the absence of valid methods and models. Food allergens may share physicochemical properties that distinguish them from nonallergens, properties that may be used as a tool to predict the inherent allergenicity of proteins newly introduced into the food supply by genetic engineering. One candidate property is stability to digestion. We have systematically evaluated the stability of food allergens that are active via the gastrointestinal tract in a simple model of gastric digestion, emphasizing the major allergens of plant-derived foods such as legumes (peanuts and soybean). Important food allergens were stable to digestion in the gastric model (simulated gastric fluid). For example, soybean beta-conglycinin was stable for 60 min. In contrast, nonallergenic food proteins, such as spinach ribulose bis-phosphate carboxylase/oxygenase, were digested in simulated gastric fluid within 15 sec. The data are consistent with the hypothesis that food allergens must exhibit sufficient gastric stability to reach the intestinal mucosa where absorption and sensitization (development of atopy) can occur. Thus, the stability to digestion is a significant and valid parameter that distinguishes food allergens from nonallergens.

  2. Electronic Networking. ERIC Digest.

    ERIC Educational Resources Information Center

    Tucker, Susan

    This digest discusses several aspects of electronic networking, including network functions, implementation, and applications in education. Electronic networking is defined as including the four basic services of electronic mail (E-mail), electronic "bulletin boards," teleconferencing, and online databases, and an overview of these four functions…

  3. Principal Mentoring. ERIC Digest.

    ERIC Educational Resources Information Center

    Malone, Robert J.

    To help new principals succeed, school districts are capitalizing on senior administrators' expertise by adding mentor programs to the practical training programs for beginning principals. This digest examines the nature of mentorships and discusses how they can prepare principals for the next stage of their careers. Although mentoring has existed…

  4. Defining Giftedness. 1985 Digest.

    ERIC Educational Resources Information Center

    McClellan, Elizabeth

    The digest examines conceptions of giftedness. A brief historical review notes L. Terman's work and impetus for increasingly broadened definitions since the 1940's. The 1969 Marland Report is cited and its definition of giftedness is presented. Current response to that definition's inclusion of six achievement areas (general academic ability,…

  5. Preventing Bullying. ERIC Digest.

    ERIC Educational Resources Information Center

    Lumsden, Linda

    Students who are the target of bullying episodes commonly suffer serious, long-term academic, physical, and emotional consequences. Unfortunately, school personnel often minimize, underestimate, tolerate, or ignore the extent of bullying and the harm it can cause. This digest examines the problem of bullying and some of its effects, and discusses…

  6. The anaerobic digestion process

    SciTech Connect

    Rivard, C.J.; Boone, D.R.

    1996-01-01

    The microbial process of converting organic matter into methane and carbon dioxide is so complex that anaerobic digesters have long been treated as {open_quotes}black boxes.{close_quotes} Research into this process during the past few decades has gradually unraveled this complexity, but many questions remain. The major biochemical reactions for forming methane by methanogens are largely understood, and evolutionary studies indicate that these microbes are as different from bacteria as they are from plants and animals. In anaerobic digesters, methanogens are at the terminus of a metabolic web, in which the reactions of myriads of other microbes produce a very limited range of compounds - mainly acetate, hydrogen, and formate - on which the methanogens grow and from which they form methane. {open_quotes}Interspecies hydrogen-transfer{close_quotes} and {open_quotes}interspecies formate-transfer{close_quotes} are major mechanisms by which methanogens obtain their substrates and by which volatile fatty acids are degraded. Present understanding of these reactions and other complex interactions among the bacteria involved in anaerobic digestion is only now to the point where anaerobic digesters need no longer be treated as black boxes.

  7. Studies on digestive physiology and feed digestibilities in captive Indian rhinoceros (Rhinoceros unicornis).

    PubMed

    Clauss, M; Polster, C; Kienzle, E; Wiesner, H; Baumgartner, K; von Houwald, F; Ortmann, S; Streich, W J; Dierenfeld, E S

    2005-01-01

    We performed intake, digestibility and ingesta passage studies in 11 Indian rhinoceroses (Rhinoceros unicornis) from four zoological institutions, using total faecal collection for the quantification of faecal output. The regularly fed zoo ration of roughage and concentrates (ration RC) and a roughage-only ration (ration R) were used; the roughage source differed between the facilities and comprised grass hay, grass silage, straw and lucerne hay. Dry matter intake ranged between 0.8 and 1.3% of body weight on ration RC and 0.5-1.2% on ration R. Digestibility coefficients achieved were similar to those reported for horses on diets of comparable composition. Endogenous losses as determined by linear regression analysis were within the range reported for horses. Measurements of faecal volatile fatty acids, faecal lactate and faecal pH also showed similarity to similar measurements in horses. The mean retention times of fluids (Co-EDTA) and particles (Cr-mordanted fibre <2 mm) in the whole gastrointestinal tract averaged 42 and 61 h, respectively, and were the longest ever recorded in a monogastric ungulate with this marker system. The results suggest that the horse is a useful model animal for designing diets for Indian rhinoceroses. Why digestive parameters are similar between these species in spite of enormous differences in body weight and retention times remains to be answered.

  8. Feline Lower Urinary Tract Disease

    MedlinePlus

    ... gland) can cause lower urinary tract disease in cats. Although they are much less common causes, FLUTD ... your veterinarian about the best diet for your cat. Many commercial diets are acceptable, but some urinary ...

  9. Applicability of the aero-optic linking equation to a highly coherent, transitional shear layer.

    PubMed

    Hugo, R J; Jumper, E J

    2000-08-20

    We investigate the validity of applying a simplified (under the assumptions of isotropic and homogeneous turbulence) aero-optic linking equation to a flow field that is known to consist of anisotropic and nonhomogeneous turbulence. The investigation is performed in the near-nozzle region of a heated two-dimensional jet, and the study makes use of a conditional-sampling experiment to acquire a spatiotemporal temperature field database for the heated-jet flow field. After compensating for the bandwidth limitations of constant-current wire temperature measurements, the temperature field database is applied to the computation of optical degradation through both direct and indirect methods, relying on the aero-optic linking equation. The simplified version of the linking equation was found to provide good agreement with direct calculations, provided that the length scale of the density fluctuations was interpreted as being the integral scale, with the limits of integration being the first two zero crossings of the covariance coefficient function. PMID:18350028

  10. Dynamics of fine particles and photo-oxidants in the Eastern Mediterranean (SUB-AERO)

    NASA Astrophysics Data System (ADS)

    Lazaridis, M.; Eleftheriadis, K.; Smolik, J.; Colbeck, I.; Kallos, G.; Drossinos, Y.; Zdimal, V.; Vecera, Z.; Mihalopoulos, N.; Mikuska, P.; Bryant, C.; Housiadas, C.; Spyridaki, A.; Astitha, Marina; Havranek, V.

    As part of the European project SUB-AERO, comprehensive aerosol and gaseous pollutant measurement campaigns were performed at the Finokalia station (July 2000 and January 2001) on the island of Crete (Greece) in combination with boat measurements in the eastern part of the Mediterranean area. The measurements were performed with the participation of nine European research institutions. The objective of the measurement campaigns was to evaluate and assess the spatial and temporal variability of photochemical pollutants and fine particles. The current overview paper presents the framework and main results of the measurements and modelling studies performed during the project. Extensive measurements of gaseous and atmospheric-aerosol physical, chemical and optical characteristics were performed during the measurement campaigns in conjunction with detailed chemical analyses of the aerosol species. Along with the experimental work mesoscale modelling, using a combination of the UAM-AERO air quality model together with the RAMS prognostic meteorological model, was used to reveal the dynamics of particulate matter and photo-oxidants. Furthermore, regional chemistry transport models were applied to determine the background and initial conditions for the mesoscale modelling.

  11. Aerosciences, Aero-Propulsion and Flight Mechanics Technology Development for NASA's Next Generation Launch Technology Program

    NASA Technical Reports Server (NTRS)

    Cockrell, Charles E., Jr.

    2003-01-01

    The Next Generation Launch Technology (NGLT) program, Vehicle Systems Research and Technology (VSR&T) project is pursuing technology advancements in aerothermodynamics, aeropropulsion and flight mechanics to enable development of future reusable launch vehicle (RLV) systems. The current design trade space includes rocket-propelled, hypersonic airbreathing and hybrid systems in two-stage and single-stage configurations. Aerothermodynamics technologies include experimental and computational databases to evaluate stage separation of two-stage vehicles as well as computational and trajectory simulation tools for this problem. Additionally, advancements in high-fidelity computational tools and measurement techniques are being pursued along with the study of flow physics phenomena, such as boundary-layer transition. Aero-propulsion technology development includes scramjet flowpath development and integration, with a current emphasis on hypervelocity (Mach 10 and above) operation, as well as the study of aero-propulsive interactions and the impact on overall vehicle performance. Flight mechanics technology development is focused on advanced guidance, navigation and control (GN&C) algorithms and adaptive flight control systems for both rocket-propelled and airbreathing vehicles.

  12. A Rapid Method to Achieve Aero-Engine Blade Form Detection

    PubMed Central

    Sun, Bin; Li, Bing

    2015-01-01

    This paper proposes a rapid method to detect aero-engine blade form, according to the characteristics of an aero-engine blade surface. This method first deduces an inclination error model in free-form surface measurements based on the non-contact laser triangulation principle. Then a four-coordinate measuring system was independently developed, a special fixture was designed according to the blade shape features, and a fast measurement of the blade features path was planned. Finally, by using the inclination error model for correction of acquired data, the measurement error that was caused by tilt form is compensated. As a result the measurement accuracy of the Laser Displacement Sensor was less than 10 μm. After the experimental verification, this method makes full use of optical non-contact measurement fast speed, high precision and wide measuring range of features. Using a standard gauge block as a measurement reference, the coordinate system conversion data is simple and practical. It not only improves the measurement accuracy of the blade surface, but also its measurement efficiency. Therefore, this method increases the value of the measurement of complex surfaces. PMID:26039420

  13. Implications of the homogeneous turbulence assumption on the aero-optic linking equation

    NASA Astrophysics Data System (ADS)

    Hugo, Ronald J.; Jumper, Eric J.

    1995-09-01

    This paper investigates the validity of applying the simplified (under the assumptions of isotropic and homogeneous turbulence) aero-optic linking equation to a flowfield that is known to consist of anisotropic and nonhomogeneous turbulence. The investigation is performed in the near nozzle-region of a heated two-dimensional jet, and the study makes use of a conditional sampling experiment to acquire a spatio-temporal temperature field data base for the heated jet flowfield. After compensating for the bandwidth limitations of constant-current-wire temperature measurements, the temperature field data base is applied to the computation of optical degradation through both direct methods and indirect methods relying on the aero-optic linking equation. The simplified version of the linking equation was found to provide very good agreement with direct calculations provided that the length scale of the density fluctuations was interpreted as being the integral scale, with the limits of the integration being the two first zero crossings of the covariance coefficient function.

  14. Applicability of the Aero-Optic Linking Equation to a Highly Coherent, Transitional Shear Layer

    NASA Astrophysics Data System (ADS)

    Hugo, Ronald J.; Jumper, Eric J.

    2000-08-01

    We investigate the validity of applying a simplified (under the assumptions of isotropic and homogeneous turbulence) aero-optic linking equation to a flow field that is known to consist of anisotropic and nonhomogeneous turbulence. The investigation is performed in the near-nozzle region of a heated two-dimensional jet, and the study makes use of a conditional-sampling experiment to acquire a spatiotemporal temperature field database for the heated-jet flow field. After compensating for the bandwidth limitations of constant-current wire temperature measurements, the temperature field database is applied to the computation of optical degradation through both direct and indirect methods, relying on the aero-optic linking equation. The simplified version of the linking equation was found to provide good agreement with direct calculations, provided that the length scale of the density fluctuations was interpreted as being the integral scale, with the limits of integration being the first two zero crossings of the covariance coefficient function.

  15. Aero-Propulsion Technology (APT) Task V Low Noise ADP Engine Definition Study

    NASA Technical Reports Server (NTRS)

    Holcombe, V.

    2003-01-01

    A study was conducted to identify and evaluate noise reduction technologies for advanced ducted prop propulsion systems that would allow increased capacity operation and result in an economically competitive commercial transport. The study investigated the aero/acoustic/structural advancements in fan and nacelle technology required to match or exceed the fuel burned and economic benefits of a constrained diameter large Advanced Ducted Propeller (ADP) compared to an unconstrained ADP propulsion system with a noise goal of 5 to 10 EPNDB reduction relative to FAR 36 Stage 3 at each of the three measuring stations namely, takeoff (cutback), approach and sideline. A second generation ADP was selected to operate within the maximum nacelle diameter constrain of 160 deg to allow installation under the wing. The impact of fan and nacelle technologies of the second generation ADP on fuel burn and direct operating costs for a typical 3000 nm mission was evaluated through use of a large, twin engine commercial airplane simulation model. The major emphasis of this study focused on fan blade aero/acoustic and structural technology evaluations and advanced nacelle designs. Results of this study have identified the testing required to verify the interactive performance of these components, along with noise characteristics, by wind tunnel testing utilizing and advanced interaction rig.

  16. Wind tunnel validation of AeroDyn within LIFES50+ project: imposed Surge and Pitch tests

    NASA Astrophysics Data System (ADS)

    Bayati, I.; Belloli, M.; Bernini, L.; Zasso, A.

    2016-09-01

    This paper presents the first set of results of the steady and unsteady wind tunnel t