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BACKGROUND: An in vivo/in vitro ileal fermentation assay using growing pigs has been developed but not yet formally validated. OBJECTIVES: This study aimed to validate the in vivo/in vitro ileal fermentation assay by comparing in vitro fermentation values with those obtained in vivo in growing pigs. The effect of raising pigs under different environmental conditions was also investigated. METHODS: Thirty piglets (1.59 ± 0.31 kg body weight, mean ± standard deviation) were subjected to 1 of 3 treatments: artificially reared (AR) (nonfarm, laboratory housing conditions) from postnatal day (PND) 7 (AR group), inoculated orally with human infant fecal extracts from birth until PND 8 and AR (AR+ group), or conventionally reared on a farm (control group). Starting at PND 7, the AR and AR+ pigs received human infant formula for 3 wk, followed by a human-type diet for 5 wk. Control pigs were weaned on the farm and, on PND 63, relocated to the laboratory animal facility. From PND 63, all pigs received a human-type diet. On PND 78, pigs were killed, after which ileal digesta were collected to perform an in vitro ileal fermentation (in vitro organic matter [OM] fermentability and organic acid production) and to determine digesta microbial composition and dietary OM fermentability in vivo. RESULTS: The rearing regimen resulted in only a few differences in ileal microbial taxonomic composition. The rearing regimen generally did not affect the in vitro production of individual organic acids. The in vivo and in vitro OM fermentability of proximal ileal digesta (19.7 ± 2.04%; mean ± SEM) was similar (P > 0.05) for the AR and control pigs but not for the AR+ pigs. CONCLUSIONS: The control-rearing regimen was preferred over AR or AR+ because of ease of implementation. The in vitro ileal fermentation assay accurately predicted the in vivo OM fermentability.
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Dieta , Íleo , Humanos , Suínos , Animais , Fermentação , Íleo/metabolismo , Fezes , Dieta/veterinária , Projetos de Pesquisa , Ração Animal/análise , DigestãoRESUMO
BACKGROUND: Bovine milk processing influences the structure of the curd formed during gastric digestion, which may alter gastric protein hydrolysis and impact amino acid (AA) release into the small intestine. OBJECTIVES: This study aimed to determine the influence of heat treatment and homogenization on the gastric protein digestion and AA emptying of bovine milk. METHODS: Nine-wk-old pigs (n = 144) consumed either raw, pasteurized nonhomogenized (PNH), pasteurized homogenized (PH), or ultra-high-temperature homogenized (UHT) bovine milk for 10 d. On day 11, fasted pigs received the milk treatment (500 mL) before gastric contents were collected at 0, 20, 60, 120, 180, and 300 min postprandially. The apparent degree of gastric protein hydrolysis (based on the release of free amino groups), apparent gastric disappearance of individual proteins [based on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gel band intensity], and the gastric emptying of digested protein and AA were determined. RESULTS: During the first 60 min, the rate of apparent gastric protein hydrolysis was fastest in pigs fed UHT milk (0.29%/min compared with on average 0.07%/min in pigs fed raw, PNH, and PH milk). Differences in the apparent degree of gastric protein hydrolysis and emptying were reflected in the rate of digested protein entering the small intestine. The AA gastric emptying half-time was generally shorter in pigs fed PH and UHT milk than in pigs fed raw and PNH milk. For example, the gastric release of total essential AA was >2-fold faster (P < 0.01) in pigs fed PH or UHT milk than that in pigs fed raw or PNH milk (i.e., homogenized compared with nonhomogenized milk). CONCLUSIONS: Heat treatment and homogenization increased the apparent gastric degree of protein hydrolysis and the release of digested protein into the small intestine. However, the rate of AA entering the small intestine was mainly increased by homogenization.
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Digestão , Esvaziamento Gástrico , Temperatura Alta , Proteínas do Leite , Animais , Digestão/fisiologia , Suínos , Proteínas do Leite/metabolismo , Proteínas do Leite/química , Humanos , Bovinos , Manipulação de Alimentos/métodos , Aminoácidos/metabolismo , Leite/química , Hidrólise , PasteurizaçãoRESUMO
BACKGROUND: Absorption of tryptophan (TRP) across the gut epithelium is potentially modulated by competing large neutral amino acids (LNAAs), which could affect the appearance of TRP and its metabolites in the bloodstream. OBJECTIVES: This study aimed to determine, in a growing pig model of an adult human, the absorption of TRP and other LNAAs from the gastrointestinal tract, and plasma appearance of TRP, LNAAs, and TRP metabolites, in response to dietary proteins varying in TRP content. METHODS: Pigs were adapted for 7 d to each of 4 diets that differed in their protein source and TRP content: 1) alpha-lactalbumin (AL; 9.95 mg TRP/g diet DM), 2) whey protein (6.59 mg TRP/g), 3) casein (3.73 mg TRP/g), or 4) zein (0.14 mg TRP/g). On day 8, pigs were euthanised after a 12-h fast (baseline), or 1, 2, 3, 4, or 6 h after they received a test meal consisting of 45 g protein, or a protein-free meal (n = 6 pigs at each time in each meal group). Tryptophan and LNAA absorption from the small intestine, and appearance of TRP, LNAAs, and TRP metabolites (melatonin, serotonin, kynurenine pathway metabolites), in the portal vein and systemic circulation, were determined. RESULTS: AL intake resulted in sustained elevated plasma TRP concentrations after an overnight fast. The amount of TRP absorbed was dose-dependently related to protein TRP content (P = 0.028), with fastest rates for pigs fed AL (371 mg/h). Portal and systemic plasma TRP, TRP/LNAA, and the TRP metabolites were highest (P ≤ 0.05) after AL intake, and remained above baseline levels for â¼4 h postprandially. Absorption rates of TRP correlated with postprandial plasma TRP and TRP metabolites (P ≤ 0.05). CONCLUSIONS: In adult humans, postprandial plasma TRP and TRP metabolite concentrations can likely be modulated by the TRP content of the meal.
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This study evaluated the importance of a correction for amino acids (AA) released into the hindgut on a measure of AA absorption kinetics and tested whether AA absorption kinetics are related to the extent of AA absorption using the growing pig as a model for humans. Thirty-six nine-week-old pigs (22·3 kg) received a diet containing whey protein as the sole protein source for 8 d. Pigs received their last meal containing the indigestible marker titanium dioxide before being euthanised at 1, 2, 3, 4, 6 and 12 h post-feeding. The entire content of each gastrointestinal tract (GIT) region was collected to determine AA released into the hindgut, and the kinetics and extent of AA absorption (uncorrected and corrected for AA entering the hindgut). Amounts of AA released into the hindgut increased over time (e.g. 33 and 180 mg of Glu for 4 and 6 h post-feeding). The corrected apparent amount of each AA absorbed from the GIT lumen after 4 h post-feeding was generally lower (P ≤ 0·05) than the uncorrected counterpart. Differences in both the kinetics and extent of AA absorption were observed across AA. For example, the time to reach half of the apparent AA absorption (T50) was 1·5 and 3·4 h for Met and Arg, respectively, whereas their extent of apparent absorption was 93 and 73 %. Negative correlations between parameters related to kinetics and the extent of apparent absorption were observed (e.g. for T50 r = -0·81; P < 0·001). The kinetics of AA absorption is related to the extent of AA absorption.
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Aminoácidos , Digestão , Humanos , Suínos , Animais , Aminoácidos/metabolismo , Intestino Delgado/metabolismo , Trato Gastrointestinal/metabolismo , Dieta/veterinária , Ração Animal/análise , Íleo/metabolismo , Fenômenos Fisiológicos da Nutrição AnimalRESUMO
This study investigated the effects of Lacticaseibacillus rhamnosus HN001 supplementation on the architecture and gene expression in small intestinal tissues of piglets used as an animal model for infant humans. Twenty-four 10-d-old entire male piglets (4·3 (sd 0·59) kg body weight) were fed an infant formula (IF) (control) or IF supplemented with 1·3 × 105 (low dose) or 7·9 × 106 (high dose) colony-forming units HN001 per ml of reconstituted formula (n 8 piglets/treatment). After 24 d, piglets were euthanised. Samples were collected to analyse the histology and gene expression (RNAseq and qPCR) in the jejunal and ileal tissues, blood cytokine concentrations, and blood and faecal calprotectin concentrations. HN001 consumption altered (false discovery rate < 0·05) gene expression (RNAseq) in jejunal tissues but not in ileal tissues. The number of ileal goblet cells and crypt surface area increased quadratically (P < 0·05) as dietary HN001 levels increased, but no increase was observed in the jejunal tissues. Similarly, blood plasma concentrations of IL-10 and calprotectin increased linearly (P < 0·05) as dietary HN001 levels increased. In conclusion, supplementation of IF with HN001 affected the architecture and gene expression of small intestine tissue, blood cytokine concentration and frequencies, and blood calprotectin concentrations, indicating that HN001 modulated small intestinal tissue maturation and immunity in the piglet model.
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Lacticaseibacillus rhamnosus , Probióticos , Humanos , Lactente , Animais , Masculino , Suínos , Probióticos/uso terapêutico , Suplementos Nutricionais , Íleo , Citocinas/genética , Complexo Antígeno L1 Leucocitário , Expressão GênicaRESUMO
BACKGROUND: When foods are subjected to heat and pressure, a proportion of lysine is structurally altered and some will revert to lysine because of acid hydrolysis during amino acid analysis. Altered lysine molecules may be partly absorbed but are not utilized post-absorption. OBJECTIVES: A guanidination-based bioassay has been developed to determine true ileal digestible reactive lysine but it was only used in animal models (pig and rat). The objective of this study was to apply the assay and determine whether there is a difference between true ileal digestible total lysine and true ileal digestible reactive lysine in adult human ileostomates. METHODS: Six cooked or processed foods were analyzed for total lysine and reactive lysine. Six adults with a fully functioning ileostomy (4 women and 2 men; age range: 41-70 y; BMI: 20.8-28.1) participated. Foods for which total lysine > reactive lysine (cooked black beans, toasted wheat bread, and processed wheat bran), as well as a protein-free diet, were consumed by the ileostomates (n = 5 to 8; test food meals contained 25 g protein) and ileal digesta was collected. Each food was ingested twice by each participant, and the digesta was pooled. The order of foods for each participant was determined according to a Youden square. True ileal digestible total lysine and true ileal digestible reactive lysine were determined and a 2-way ANOVA model was used to analyze data. RESULTS: True ileal digestible reactive lysine was significantly lower than true ileal digestible total lysine for cooked black beans, toasted wheat bread, and processed wheat bran by 89%, 55%, and 85%, respectively (P< 0.05). CONCLUSIONS: True ileal digestible reactive lysine was lower than true ileal digestible total lysine, similar to that previously reported in pigs and rats, demonstrating the importance of determining the true ileal digestible reactive lysine contents of processed foods.
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Digestão , Lisina , Masculino , Humanos , Adulto , Feminino , Ratos , Animais , Suínos , Pessoa de Meia-Idade , Idoso , Lisina/metabolismo , Aminoácidos/metabolismo , Íleo/metabolismo , Grão Comestível/química , Fibras na Dieta/análise , Ração Animal/análiseRESUMO
BACKGROUND: Organic acid synthesis by the hindgut microbiota is commonly believed to be mainly of fermentable material of dietary origin. OBJECTIVE: This study aimed to determine the hindgut organic acid synthesis from fermentable material of dietary (mainly fiber) or nondietary origin for different types and amounts of dietary fiber in growing pigs used as a model for adult humans. METHOD: Seven fiber-containing diets were formulated: 4 fiber types (cellulose, gum acacia, oligofructose, and pectin) at 6% of the diet and 3 (gum acacia, oligofructose, and pectin) at 3% as the sole fiber source. Ileal cannulated female pigs (n = 14; Landrace/Large white) were fed the fiber-containing diets (n = 6 pigs/diet) for 11 days (fiber phase) followed by 3 days on a fiber-free diet (fiber-free phase), using a replicated Youden square. Ileal digesta for each phase were collected and fermented in vitro with a pooled fecal microbial inoculum prepared from feces collected during the fiber phase to determine the organic acids synthesized from fermentable material of dietary (fiber phase) and nondietary (fiber-free phase) origins. RESULTS: The total amount of each individual organic acid synthesized during in vitro hindgut fermentation differed (P ≤ 0.05) across the types and amounts of dietary fiber intake. For example, the amount of acetate was 3.6-fold higher (P ≤ 0.05) for pigs fed the 6% pectin-containing diet than those fed the 6% oligofructose-containing diet. The nondietary substrate contributed between 36% (hexanoate) and 70% (succinate) to the total hindgut organic acid synthesis. The adaptation to the different fiber-containing diets led to different amounts of some organic acids of nondietary origin. CONCLUSIONS: The total amount of organic acids synthesized in the hindgut by the resident microbes is influenced by the type and amount of dietary fiber consumed. This study quantifies the interaction between both dietary and nondietary fermentable materials in hindgut fermentation.
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BACKGROUND: Infant formula (IF) has to provide at least the same amount of amino acids (AAs) as human milk (HM). AA digestibility in HM and IF was not studied extensively, with no data available for tryptophan digestibility. OBJECTIVES: The present study aimed to measure the true ileal digestibility (TID) of total nitrogen and AAs in HM and IF to estimate AA bioavailability using Yucatan mini-piglets as an infant model. METHODS: Twenty-four 19-day-old piglets (males and females) received either HM or IF for 6 days or a protein-free diet for 3 days, with cobalt-EDTA as an indigestible marker. Diets were fed hourly over 6 h before euthanasia and digesta collection. Total N, AA, and marker contents in diets and digesta were measured to determine the TID. Unidimensional statistical analyses were conducted. RESULTS: Dietary N content was not different between HM and IF, while true protein was lower in HM (-4 g/L) due to a 7-fold higher non-protein N content in HM. The TID of total N was lower (P < 0.001) for HM (91.3 ± 1.24%) than for IF (98.0 ± 0.810%), while the TID of amino acid nitrogen (AAN) was not different (average of 97.4 ± 0.655%, P = 0.272). HM and IF had similar (P > 0.05) TID for most of the AAs including tryptophan (96.7 ± 0.950%, P = 0.079), except for some AAs (lysine, phenylalanine, threonine, valine, alanine, proline, and serine), with small significant difference (P < 0.05). The first limiting AA was the aromatic AAs, and the digestible indispensable AA score (DIAAS) was higher for HM (DIAASHM = 101) than for IF (DIAASIF = 83). CONCLUSION: HM, compared to IF, had a lower TID for total N only, whereas the TID of AAN and most AAs, including Trp, was high and similar. A larger proportion of non-protein N is transferred to the microbiota with HM, which is of physiological relevance, although this fraction is poorly considered for IF manufacturing.
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Aminoácidos , Leite Humano , Masculino , Recém-Nascido , Lactente , Feminino , Humanos , Animais , Suínos , Aminoácidos/metabolismo , Leite Humano/química , Fórmulas Infantis/química , Triptofano/metabolismo , Nitrogênio/metabolismo , Digestão/fisiologia , Íleo/metabolismo , Dieta , Dieta com Restrição de Proteínas , Ração Animal/análiseRESUMO
BACKGROUND: Stenosis, fistulization, and perforation of the bowel are severe outcomes which can occur in patients with Crohn's disease. Accurate prediction of these events may enable clinicians to alter treatment strategies and avoid these outcomes. AIMS: To study the correlation between longitudinal laboratory testing and subsequent intestinal complications in patients with Crohn's disease. METHODS: An observational cohort of patients with Crohn's disease at a single center were analyzed between 01/01/1994 and 06/30/2016. A complication was defined as the development of an intestinal fistula, stenosis, or perforation. Exploratory analysis using Cox regression was performed to select the best statistical method to represent longitudinal laboratory data. Cox regression was used to identify laboratory variables independently associated with the development of a subsequent complication. A clinical scoring tool was designed. RESULTS: In 246 patients observed over a median of 5.72 years, 134 complications occurred. Minimum or maximum value in a preceding window period of one year was most strongly associated with subsequent complication. A Longitudinal Laboratory score of ≥ 2 (maximum albumin level < 39 g/L = 1, maximum mean cell volume < 88 fL = 1, minimum platelet count > 355 × 109/L = 1, minimum C reactive protein > 5 mg/L = 1) was 62% sensitive and 91% specific in identifying patients who develop a subsequent complication. CONCLUSION: A consistent reduction in serum albumin and mean cell volume, and a consistent increase in platelet count and C reactive protein were associated with a subsequent complication in patients with Crohn's disease. Longitudinal laboratory tests may be used as described in this paper to provide a rational for earlier escalation of therapy.
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Doença de Crohn , Humanos , Doença de Crohn/complicações , Constrição Patológica , Proteína C-Reativa/metabolismo , Intestinos , Contagem de PlaquetasRESUMO
Protein is considered to be the most satiating food macronutrient and the satiating effect may be dependent on the source of the protein. The maize-derived protein zein and milk protein casein have been shown previously to lower stomach emptying rate more than dairy whey protein, but the effect of zein on satiety has not been evaluated. The objective was to compare the satiating effects of zein and casein, with whey protein and its protein component α-lactalbumin. The study was a randomised crossover design with thirteen normal-weight men (mean age 27.8 years and mean BMI 24.4 kg/m2) consuming isoenergetic (â¼4000 kJ, â¼990 kcal) preload mixed meals enriched with Zein, Casein, whey protein isolate (Whey), α-lactalbumin (ALac), or maltodextrin carbohydrate (Carb). Consumption of an ad libitum standardised test meal of chicken fried rice and water provided 360 min following ingestion of the preload meal was measured, and subjective feelings of appetite (hunger, fullness, desire to eat, and prospective food consumption) were assessed using 100-mm visual analogue scales (VAS). There were no differences among the five preload mixed meals in the amount of chicken fried rice consumed at the ad libitum test meal (mean ± sem: 531.6 ± 35.0 g, p = 0.47) or total (preload + test meal) energy intakes (mean ± sem: 5780.5 ± 146.0 kJ, p = 0.29). The subjective VAS appetite ratings and total area under the curve responses for hunger, fullness, desire to eat, and prospective food consumption, were not different following consumption of all five preload mixed meals (p > 0.05). The findings indicate that the effects of zein and casein on satiety were not different from the satiating effects of whey protein and α-lactalbumin.
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Ingestão de Alimentos , Proteínas do Leite , Saciação , Proteínas do Soro do Leite , Zeína , Caseínas/farmacologia , Lactalbumina/farmacologia , Proteínas do Soro do Leite/farmacologia , Zea mays , Estudos Cross-Over , Humanos , Masculino , AdultoRESUMO
OBJECTIVES: To identify gestational complications associated with SARS-CoV-2 infection in pregnant women during 2020-2021. CONTENT: The risk of gestational complications was confirmed during SARS-CoV and MERS-CoV infection. However, this is not robust for COVID-19 because there is still no scientific evidence from longitudinal studies. A systematic review was performed using four databases, and 14 prospective or retrospective cohorts were finally included in the analysis. SUMMARY: The most frequently associated sociodemographic characteristic or comorbidity was the presence of any previous comorbidity (9 studies, 64.3%), followed by ethnicity and age (6 studies each one, 42.9%). The most frequently associated gestational complications in mothers were the admission to Intensive Care Unit (4 studies, 28.6%) and gestational age at delivery <37 weeks (3 studies, 21.4%). The most frequently associated gestational complications in newborns were preterm birth (4 studies, 28.6%) and the admission to Neonatal Intensive Care Unit (2 studies, 14.3%). OUTLOOK: Pregnant women infected with SARS-CoV-2 appear to have a higher risk of admission to Intensive Care Unit. Newborns of mothers infected with SARS-CoV-2 appear to have a higher risk of preterm birth and admission to Neonatal Intensive Care Unit.
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COVID-19 , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Recém-Nascido , Gravidez , Feminino , Humanos , Lactente , COVID-19/complicações , COVID-19/epidemiologia , SARS-CoV-2 , Gestantes , Estudos Prospectivos , Estudos Retrospectivos , Complicações Infecciosas na Gravidez/epidemiologia , Transmissão Vertical de Doenças Infecciosas , Estudos Longitudinais , Resultado da GravidezRESUMO
BACKGROUND: It is not feasible to determine the true ileal amino acid (AA) digestibility of protein sources in humans on a routine basis, and the growing pig has been recommended as an animal model for this purpose but requires further validation. OBJECTIVES: To determine and compare true ileal AA digestibility between adult human ileostomates and growing cannulated pigs for a range of food proteins. METHODS: Seven protein sources (black beans, bread, collagen, pigeon peas, wheat bran, whey protein isolate, and zein) that spanned the range of digestibilities typically seen in foods were evaluated. Six female growing pigs received each of the protein sources, as well as a protein-free diet, and digesta were collected via ileal T-cannula. Adult human ileostomates consumed the same protein sources (5-8 ileostomates, depending on the protein source), as well as a protein-free diet, and digesta were collected. Titanium dioxide and celite were included in the diets as indigestible markers. True ileal AA digestibility coefficients were determined. RESULTS: There was a significant effect of protein source (P ≤ 0.001) for all AAs. The effect of species was not significant (P > 0.05) except for total lysine (but not for available lysine). When analyzed within diets, the statistically significant species effect for true lysine digestibility was found for black beans only. Pig and human digestibility values were generally highly and significantly (P ≤ 0.05) correlated. A linear regression equation derived for true ileal AA digestibility (given as coefficients) determined in the human and pig for the overall mean of all AAs was (y = human, x = pig) y = 1.00x - 0.010, with the slope not statistically significant (P > 0.05) from unity and the intercept not different (P > 0.05) from zero. CONCLUSIONS: True ileal AA digestibility values determined in the growing pig can be directly used for predicting digestibility in adult humans.
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Aminoácidos , Digestão , Aminoácidos/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Feminino , Humanos , Íleo/metabolismo , Lisina/metabolismo , SuínosRESUMO
This study investigated the structural and physicochemical changes that occur in milk, a naturally designed complex structured emulsion, during gastric digestion using the bottle-fed piglet as an animal model. The gastric digestions of cow, goat, and sheep milk were compared in male piglets euthanized at different postfeeding times to collect the stomach chyme. The cow and noncow milks separated into curd (aggregated caseins) and liquid (mostly soluble whey) phases in the piglet's stomach. For milk from all the species, the curd remained longer in the stomach because of its slow disintegration, whereas the liquid phase emptied readily. The majority of the fat globules were found to be entrapped within the protein network of the curd. The rate of release of fat globules was strongly dependent on the breakdown of the surrounding protein network of the curd. The consistency of the gastric curds changed as digestion progressed, with goat and sheep milk curds having relatively softer curd consistency and less fused protein networks, especially toward the end of digestion. This might have led to the lower protein and fat retention in the goat and sheep milk curds and relatively faster gastric emptying of these nutrients from goat and sheep milk in comparison to cow milk. This in vivo study provided new and enhanced understanding of the mechanisms of the gastric digestion of milk from different species. It may have implications for developing bioinspired structures for the controlled digestion and delivery of nutrients.
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Digestão , Leite , Animais , Bovinos , Eutanásia Animal , Feminino , Cabras , Masculino , Leite/química , Ovinos , Estômago , SuínosRESUMO
The oxygen (O2 ) concentration of gastrointestinal tract (GIT) contents decreases distally, but little is known about how O2 concentrations are influenced by ingestion of a meal. The O2 concentration in luminal contents at different GIT locations (stomach [cardia and pylorus], proximal, mid- and distal small intestine and caecum) and how these concentrations changed post-prandially were determined. Fifty entire male pigs (22 kg bodyweight at the start of study) were fed semi-synthetic diets containing casein, α-lactalbumin, whey protein isolate or zein as the sole source of protein for 8 days. A further group of pigs received the casein diet for six days and a semi-synthetic protein-free diet for a further 2 days. On day 8, pigs (n = 2 per diet and time point) were euthanized post-prandially (0, 1, 2, 4 and 6 h), and the stomach, small intestine and caecum were isolated and O2 determined in the GIT contents. Observations at each time point were averaged across the diets (n = 10). The mean O2 concentration was markedly higher (p ≤ 0.05) in the stomach compared with the rest of the GIT. The O2 concentration was similar in the small intestinal regions (p > 0.05; 1.0%-1.1%) and the caecum (0.9%), apart for the proximal small intestine which had a 24% higher (p ≤ 0.05) O2 concentration than the caecum. The mean O2 concentration in the GIT varied post-prandially (p ≤ 0.05). The O2 concentration in the cardia decreased 1.8%/h over the first two hours post-feeding and thereafter increased 0.3%/h (p ≤ 0.05). In the caecum, the O2 concentration was constant during the first 4 h and thereafter increased slightly (p ≤ 0.05). The flow of food through the GIT influenced both the concentration and amount of O2 in GIT luminal contents.
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Ração Animal , Trato Gastrointestinal , Ração Animal/análise , Animais , Caseínas/metabolismo , Dieta/veterinária , Conteúdo Gastrointestinal , Trato Gastrointestinal/metabolismo , Masculino , Oxigênio/metabolismo , SuínosRESUMO
BACKGROUND: The degree of ileal organic matter (OM) fermentation appears to be comparable to hindgut fermentation in growing pigs. OBJECTIVES: This study aimed to determine if dietary fiber sources with known different total gastrointestinal tract (GIT) fermentability in humans affect ileal and hindgut microbial communities and ileal fermentation in growing pigs used as an animal model for human adults. METHODS: Male pigs (21 kg bodyweight; 9 wk old; PIC Camborough 46 × PIC boar 356L; n = 8/diet) were fed for 42 d a diet containing cellulose (CEL, low fermentability) as the sole fiber source (4.5%) or diets in which half of the CEL was replaced by moderately fermentable fiber, psyllium (PSY), or kiwifruit (KF) fiber. For each diet, terminal jejunal (substrate) and ileal (inoculum) digesta were collected from euthanized animals for in vitro ileal fermentation (2 h). Terminal ileal (substrate) and cecal (inoculum) digesta were used for in vitro hindgut fermentation (24 h). After in vitro fermentations, OM fermentation and short-chain fatty acid (SCFA) production were determined. Ileal digesta and feces were collected for microbial analysis. Data were analyzed by 2-factor ANOVA (diet × GIT region). RESULTS: In vitro ileal OM fermentation was on average 22% and comparable to hindgut OM fermentation. Ileal and hindgut OM fermentation, SCFA production, and microbial community composition changed (P < 0.05) when CEL was partially replaced by KF or PSY. For instance, pigs fed the PSY diet had 3-fold higher (P ≤ 0.05) number of ileal and fecal bacteria than pigs fed the CEL and KF diets. Pigs fed the CEL diet had 4-fold higher (P ≤ 0.05) hindgut valeric acid production than pigs fed the other diets. CONCLUSIONS: Ileal fermentation is quantitatively significant. Partial substitution of CEL with more fermentable fibers influences both ileal and hindgut microbial communities and the fermentation in growing pigs.
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Fibras na Dieta , Microbiota , Ração Animal/análise , Animais , Dieta/veterinária , Fibras na Dieta/análise , Digestão , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Fermentação , Íleo/metabolismo , Masculino , SuínosRESUMO
This study characterised the in vitro ileal fermentability of different substrates in the growing pig, adopted as an animal model for the adult human, and compared in vitro ileal and caecal fermentation in the pig. Substrates (arabinogalactan (AG), cellulose, fructo-oligosaccharide (FOS), inulin, mucin, citrus pectin and resistant starch) were fermented in vitro (ileal 2 h and caecal 24 h) with an ileal or caecal inoculum prepared from ileal or caecal digesta collected from growing pigs (n 5) fed a human-type diet for 15 d. The organic matter (OM) fermentability and production of organic acids were determined. In general, there was considerable in vitro ileal fermentation of fibre, and the substrates differed (P < 0·001) for both in vitro ileal and caecal OM fermentability and for organic acid production. Pectin had the greatest in vitro ileal OM fermentability (26 %) followed by AG, FOS and resistant starch (15 % on average), and cellulose, inulin and mucin (3 % on average). The fermentation of FOS, inulin and mucin was greater for in vitro caecal fermentation compared with the ileal counterpart (P ≤ 0·05). In general, the organic acid production was higher for in vitro caecal fermentation (P ≤ 0·05). For instance, the in vitro ileal acetic acid production represented 4-46 % of in vitro caecal production. Energy from fibre fermentation of 0·6-11 kJ/g substrate fermented could be expected in the ileum of the pig. In conclusion, substrates are fermented in both the ileum and caecum. The degree of fermentation varies among substrates, especially for in vitro ileal fermentation.
Assuntos
Bactérias/metabolismo , Ceco/microbiologia , Dieta Ocidental , Fibras na Dieta/metabolismo , Fermentação , Íleo/microbiologia , Animais , Ceco/metabolismo , Celulose/metabolismo , Fibras na Dieta/administração & dosagem , Digestão , Galactanos/metabolismo , Humanos , Íleo/metabolismo , Masculino , Modelos Animais , Mucinas/metabolismo , Oligossacarídeos/metabolismo , Pectinas/metabolismo , Amido/metabolismo , SuínosRESUMO
Actinobacteria embroil Gram-positive microbes with high guanine and cytosine contents in their DNA. They are the source of most antimicrobials of bacterial origin utilized in medicine today. Their genomes are among the richest in novel secondary metabolites with high biotechnological potential. Actinobacteria reveal complex patterns of evolution, responses, and adaptations to their environment, which are not yet well understood. We analyzed three novel plant isolates and explored their habitat adaptation, evolutionary patterns, and potential secondary metabolite production. The phylogenomically characterized isolates belonged to Actinoplanes sp. TFC3, Streptomyces sp. L06, and Embleya sp. NF3. Positively selected genes, relevant in strain evolution, encoded enzymes for stress resistance in all strains, including porphyrin, chlorophyll, and ubiquinone biosynthesis in Embleya sp. NF3. Streptomyces sp. L06 encoded for pantothenate and proteins for CoA biosynthesis with evidence of positive selection; furthermore, Actinoplanes sp. TFC3 encoded for a c-di-GMP synthetase, with adaptive mutations. Notably, the genomes harbored many genes involved in the biosynthesis of at least ten novel secondary metabolites, with many avenues for future new bioactive compound characterization-specifically, Streptomyces sp. L06 could make new ribosomally synthesized and post-translationally modified peptides, while Embleya sp. NF3 could produce new non-ribosomal peptide synthetases and ribosomally synthesized and post-translationally modified peptides. At the same time, TFC3 has particularly enriched in terpene and polyketide synthases. All the strains harbored conserved genes in response to diverse environmental stresses, plant growth promotion factors, and degradation of various carbohydrates, which supported their endophytic lifestyle and showed their capacity to colonize other niches. This study aims to provide a comprehensive estimation of the genomic features of novel Actinobacteria. It sets the groundwork for future research into experimental tests with new bioactive metabolites with potential application in medicine, biofertilizers, and plant biomass residue utilization, with potential application in medicine, as biofertilizers and in plant biomass residues utilization. KEY POINTS: ⢠Potential of novel environmental bacteria for secondary metabolites production ⢠Exploring the genomes of three novel endophytes isolated from a medicinal tree ⢠Pan-genome analysis of Actinobacteria genera.
Assuntos
Actinobacteria , Streptomyces , Actinobacteria/genética , Genômica , Filogenia , Policetídeo Sintases/genética , Streptomyces/genéticaRESUMO
Dietary fibre fermentation in humans and monogastric animals is considered to occur in the hindgut, but it may also occur in the lower small intestine. This study aimed to compare ileal and hindgut fermentation in the growing pig fed a human-type diet using a combined in vivo/in vitro methodology. Five pigs (23 (sd 1·6) kg body weight) were fed a human-type diet. On day 15, pigs were euthanised. Digesta from terminal jejunum and terminal ileum were collected as substrates for fermentation. Ileal and caecal digesta were collected for preparing microbial inocula. Terminal jejunal digesta were fermented in vitro with a pooled ileal digesta inoculum for 2 h, whereas terminal ileal digesta were fermented in vitro with a pooled caecal digesta inoculum for 24 h. The ileal organic matter fermentability (28 %) was not different from hindgut fermentation (35 %). However, the organic matter fermented was 66 % greater for ileal fermentation than hindgut fermentation (P = 0·04). Total numbers of bacteria in ileal and caecal digesta did not differ (P = 0·09). Differences (P < 0·05) were observed in the taxonomic composition. For instance, ileal digesta contained 32-fold greater number of the genus Enterococcus, whereas caecal digesta had a 227-fold greater number of the genus Ruminococcus. Acetate synthesis and iso-valerate synthesis were greater (P < 0·05) for ileal fermentation than hindgut fermentation, but propionate, butyrate and valerate synthesis was lower. SCFA were absorbed in the gastrointestinal tract location where they were synthesised. In conclusion, a quantitatively important degree of fermentation occurs in the ileum of the growing pig fed a human-type diet.
Assuntos
Ceco/metabolismo , Dieta , Fermentação , Íleo/metabolismo , Animais , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/metabolismo , Ceco/microbiologia , Fibras na Dieta/administração & dosagem , Ácidos Graxos Voláteis/metabolismo , Humanos , Íleo/microbiologia , SuínosRESUMO
The effect of kiwi fruit at two dietary levels on the adaptation of intestinal fermentation over time in the growing pig was studied. A semi-synthetic fibre-free diet and two semi-synthetic diets containing kiwi fruit as a model fibre source (133 or 266 g/kg (DM basis); 28 or 48 g fibre/kg) were formulated and the diets contained titanium dioxide as an indigestible marker. A total of fourteen ileal cannulated pigs (41 kg body weight) were fed the fibre-free diet for 7 d followed by either the low or high kiwi fruit-containing diets (n 7/diet) for a further 44 d. Ileal digesta and faeces were collected at five times throughout the study. Ileal digesta were fermented (in vitro) with a standard pooled human faecal inoculum, while fresh pig faeces were used as inocula to ferment in vitro a standard purified fibre. Observations were normalised for diet DM intake using the marker. The 16S ribosomal RNA gene copy number of ileal and total faecal bacteria were high for the high-kiwi fruit level diet (P<0·05). The ileal bacteria tended to decrease over time (P<0·1), while the faecal bacteria increased (P<0·05), at the same rate for both diets. The amounts of crude protein and insoluble dietary fibre entering the hindgut changed over time similarly for both diets, whereas for starch it changed only for the low kiwi fruit-containing diet (P<0·05). Changes over time were also observed for the predicted hindgut valeric acid production and butyric acid absorption (P<0·05). In conclusion, adaptational changes over time of some characteristics of intestinal fermentation depended on the dietary level of kiwi fruit.
RESUMO
BACKGROUND AND OBJECTIVES: In recent years, the hypothesis that increasing the empowerment of patients can help to improve health outcomes and rationalize the use of health services has become relevant, especially for chronic diseases. Developing validated measurement tools is necessary to achieve this goal. In the field of dermatology, there are few studies related to empowerment of the patient. The aim of the present research is to develop and validate a self-administered questionnaire for adult patients diagnosed with atopic dermatitis (AD) in order to measure their level of empowerment. METHODS: After a literature review and the establishment of consulting groups of patients and dermatologists, a large battery of 35 items was generated, based on the dimensions included in previous empowerment descriptions. A multidisciplinary group selected the 20 most suitable items to include in the questionnaire. A cross-sectional study was carried out with the items included in the questionnaire as well as demographic and clinical characteristics. To reduce the number of items and measure the construct validity, an exploratory factorial analysis (EFA) of the primary components and varimax rotation were used. Cronbach's α was used to measure the reliability of the individual scales and the global questionnaire. RESULTS: 242 valid questionnaires were included. After completion of the EFA, the final Dermatitis Atópica EMPoderamiento (DATEMP) questionnaire was composed of 17 items that converged on four factors. The four scales had adequate reliability: "Knowledge" (Cronbach's alpha = 0.808), "Abilities" (Cronbach's alpha = 0.744), "Intention to change" (Cronbach's alpha = 0.798) and "Coping skills" (Cronbach's alpha = 0.772). The overall Cronbach's α of the questionnaire was 0.764. CONCLUSIONS: The DATEMP questionnaire is the first specific empowerment measurement instrument developed for patients with AD that has demonstrated adequate levels of reliability and construct validity. It is a self-administered questionnaire that is simple and quick to answer.