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1.
Nat Med ; 5(11): 1303-7, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10545998

RESUMO

The mechanisms of allograft tolerance have been classified as deletion, anergy, ignorance and suppression/regulation. Deletion has been implicated in central tolerance, whereas peripheral tolerance has generally been ascribed to clonal anergy and/or active immunoregulatory states. Here, we used two distinct systems to assess the requirement for T-cell deletion in peripheral tolerance induction. In mice transgenic for Bcl-xL, T cells were resistant to passive cell death through cytokine withdrawal, whereas T cells from interleukin-2-deficient mice did not undergo activation-induced cell death. Using either agents that block co-stimulatory pathways or the immunosuppressive drug rapamycin, which we have shown here blocks the proliferative component of interleukin-2 signaling but does not inhibit priming for activation-induced cell death, we found that mice with defective passive or active T-cell apoptotic pathways were resistant to induction of transplantation tolerance. Thus, deletion of activated T cells through activation-induced cell death or growth factor withdrawal seems necessary to achieve peripheral tolerance across major histocompatibility complex barriers.


Assuntos
Apoptose/imunologia , Sobrevivência de Enxerto/imunologia , Imunoconjugados , Linfócitos T/imunologia , Imunologia de Transplantes , Abatacepte , Animais , Antígenos CD , Antígenos de Diferenciação/imunologia , Antígenos CD28/imunologia , Complexo CD3/imunologia , Antígeno CTLA-4 , Divisão Celular , Citometria de Fluxo , Camundongos , Camundongos Transgênicos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Linfócitos T/citologia , Proteína bcl-X
2.
Poult Sci ; 100(3): 100800, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33518302

RESUMO

A meta-analysis of 19 floor-pen trials (579 replicate pen observations) in diverse geographies, basal diets, seasons, and medication programs was carried out to evaluate the effects of 2 precision glycan microbiome metabolic modulators (MMM1 and MMM2) on the performance of broiler chickens. In each trial, negative-control (NC) diets were compared with either MMM1 (14 trials) or MMM2 (8 trials), supplemented at an intended dose of 500 g/MT from hatch to 31 to 42 d. A dose response of MMM2 was evaluated in 8 trials at doses of 100, 250, 500, and 1,000 g/MT, not all present in each trial. Linear mixed-effect models were constructed for the final BW, cumulative feed intake, feed conversion ratio (FCR) corrected by mortality and BW (cFCR), and mortality, with Treatment as the fixed effect, nested random effects of Trial and Block, and adjustments for heterogeneity of variances. A significance level of P < 0.05 was used. In one of the studies, cecal content samples were collected at 42 d for analysis of microbiome gene abundance. Microbiome metabolic modulator 2 exhibited a reduction of the cFCR of 0.06 g feed/g BW gain compared with the NC and 0.03 g feed/g BW gain compared with MMM1, whereas MMM1 reduced the cFCR by 0.03 g feed/g BW gain compared with NC. Both MMM1 and MMM2 increased the final BW compared with the NC by 43 and 48 g/bird, respectively, with no difference among them. Compared with NC, feed intake was increased by MMM1 (+51 g/bird) and reduced by MMM2 (-74 g/bird). A one-directional dose response of the MMM2 ingredient was observed for the final BW (increasing) and cFCR (decreasing), whereas the feed intake response reached a minimum at 500 g/MT. The metagenomic analysis confirmed an increase in the abundance of genes belonging to the acrylate pathway, which is involved in propionate production, as well as arginine-N-succinyl transferase which is involved in the catabolism of arginine, in response to MMM2. Differential glycan structures of the MMM had an impact on the size and consistency of performance effects in broilers.


Assuntos
Aminoácidos , Fenômenos Fisiológicos da Nutrição Animal , Ceco , Galinhas , Suplementos Nutricionais , Metabolismo Energético , Microbiota , Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Ceco/microbiologia , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Galinhas/microbiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Metabolismo Energético/efeitos dos fármacos , Metagenoma , Microbiota/efeitos dos fármacos , Distribuição Aleatória
3.
J Neonatal Perinatal Med ; 13(1): 71-79, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31771077

RESUMO

BACKGROUND: Use of human milk is recommended for low birth weight (VLBW) infants, but must be safety fortified with sterile liquid fortifiers to be nutritionally sufficient. Due to clinical concern for a high incidence of metabolic acidosis among VLBW infants fed human milk fortified with acidified liquid human milk fortifier (ALHMF), we aimed to retrospectively compare the outcomes of infants fed ALHMF to those fortified with non-acidified liquid HMF (NLHMF). METHODS: Medical records of VLBW neonates admitted to our institution's neonatal intensive care unit from July 1st, 2013 to June 30th, 2014 were reviewed. 129 patients were included in the study, 61 of which received ALHMF and 68 received NLHMF. Metabolic, nutritional and clinical outcomes, including growth, were compared between the two cohorts. RESULTS: Of the infants who received ALHMF, 70.5% developed metabolic acidosis compared to only 11.8% in the NLHMF group (p < 0.001). In addition, infants who received NLHMF had a 10% greater growth velocity during the period of fortification (p = 0.01). During the full course of hospitalization, no difference in growth velocity was seen between the groups and greater length gains were found in the ALHMF group. CONCLUSIONS: The use of human milk fortified with ALHMF was associated with an increased incidence of metabolic acidosis and poorer growth during the period of fortification when compared to NLHMF-fortified feedings. These growth effects were not apparent when the duration of hospitalization was considered, suggesting a need for further study to better characterize the advantages and disadvantages of each fortifier.


Assuntos
Acidose/epidemiologia , Suplementos Nutricionais , Alimentos Fortificados , Leite Humano , Aumento de Peso , Estatura , Peso Corporal , Nutrição Enteral/métodos , Feminino , Cabeça/crescimento & desenvolvimento , Humanos , Lactente Extremamente Prematuro , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Unidades de Terapia Intensiva Neonatal , Masculino , Estudos Retrospectivos
4.
Trends Biochem Sci ; 23(5): 162-9, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9612078

RESUMO

Many catabolic pathways begin with an ATP-requiring activation step, after which further metabolism yields a surplus of ATP. Such a 'turbo' principle is useful but also contains an inherent risk. This is illustrated by a detailed kinetic analysis of a paradoxical Saccharomyces cerevisiae mutant; the mutant fails to grow on glucose because of overactive initial enzymes of glycolysis, but is defective only in an enzyme (trehalose 6-phosphate synthase) that appears to have little relevance to glycolysis. The ubiquity of pathways that possess an initial activation step, suggests that there might be many more genes that, when deleted, cause rather paradoxical regulation phenotypes (i.e. growth defects caused by enhanced utilization of growth substrate).


Assuntos
Trifosfato de Adenosina/metabolismo , Saccharomyces cerevisiae/metabolismo , Retroalimentação , Glicólise/fisiologia , Fenótipo , Saccharomyces cerevisiae/genética
5.
Sci Rep ; 8(1): 5880, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29651010

RESUMO

The establishment of a healthy gastrointestinal milieu may not only offer an opportunity to reduce swine production costs but could also open the way for a lifetime of human health improvement. This study investigates the effects of feeding soluble fibre from flaxseed meal-containing diet (FM) and insoluble fibre from oat hulls-containing diet (OH) on histomorphological characteristics, digesta- and mucosa-associated microbiota and their associations with metabolites in pig intestines. In comparison with the control (CON) and OH diets, the consumption of FM increased (P < 0.001) the jejunal villi height (VH) and the ratio of VH to crypt depths. The PERMANOVA analyses showed distinct (P < 0.05) microbial communities in ileal digesta and mucosa, and caecal mucosa in CON and FM-diets fed pigs compared to the OH diet-fed pigs. The predicted functional metagenomes indicated that amino acids and butanoate metabolism, lysine degradation, bile acids biosynthesis, and apoptosis were selectively enhanced at more than 2.2 log-folds in intestinal microbiota of pigs fed the FM diet. Taken together, flaxseed meal and oat hulls supplementation in growing pigs' diets altered the gastrointestinal development, as well as the composition and function of microbial communities, depending on the intestinal segment and physicochemical property of the dietary fibre source.


Assuntos
Avena , Suplementos Nutricionais , Linho , Trato Gastrointestinal/efeitos dos fármacos , Animais , Ácidos e Sais Biliares/biossíntese , Ácidos e Sais Biliares/genética , Fibras na Dieta/administração & dosagem , Digestão/efeitos dos fármacos , Digestão/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/crescimento & desenvolvimento , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Metagenoma/efeitos dos fármacos , Metagenoma/genética , Suínos/crescimento & desenvolvimento
6.
J Clin Invest ; 108(6): 895-903, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11560959

RESUMO

Primary T cell proliferative responses to TCR ligation plus CD28 costimulation are surprisingly heterogeneous. Many cells that enter G1 fail to progress further through the cell cycle, and some of these cells subsequently fail to divide upon restimulation, even in the presence of IL-2. Such IL-2-refractory anergy is distinct from the IL-2-reversible anergy induced by TCR occupancy in the absence of CD28 costimulation. Here, we focus on the contributions of cell cycle progression and costimulatory (CD28/CTLA-4) signals in the regulation of anergy. We show that CD28 costimulation is not sufficient for anergy avoidance and that activated T cells must progress through the cell cycle in order to escape anergy. Induction of this "division-arrest" form of anergy requires CTLA-4 signaling during the primary response. Also, cell division per se is not sufficient for anergy avoidance: the few T cells that undergo multiple rounds of cell division during overt CD28 costimulatory blockade do not escape the ultimate induction of clonal anergy. Anergy avoidance by primary T cells is thus a multistep process: in order to participate in a productive immune response, an individual T cell activated through its antigen receptor must receive CD28 costimulation and progress through the cell cycle. Anergy may be induced either through a combination of CTLA-4 signaling and the failure of cell cycle progression, or through a proliferation-independent mechanism in which TCR ligation occurs in the absence of CD28.


Assuntos
Antígenos de Diferenciação/imunologia , Antígenos CD28/imunologia , Anergia Clonal , Imunoconjugados , Linfócitos T/imunologia , Proteínas Supressoras de Tumor , Abatacepte , Animais , Antígenos CD , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Antígeno CTLA-4 , Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Inibidor de Quinase Dependente de Ciclina p27 , Feminino , Humanos , Técnicas In Vitro , Interleucina-2/farmacologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais , Linfócitos T/citologia
7.
Nat Biotechnol ; 19(1): 45-50, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11135551

RESUMO

A large proportion of the 6,000 genes present in the genome of Saccharomyces cerevisiae, and of those sequenced in other organisms, encode proteins of unknown function. Many of these genes are "silent, " that is, they show no overt phenotype, in terms of growth rate or other fluxes, when they are deleted from the genome. We demonstrate how the intracellular concentrations of metabolites can reveal phenotypes for proteins active in metabolic regulation. Quantification of the change of several metabolite concentrations relative to the concentration change of one selected metabolite can reveal the site of action, in the metabolic network, of a silent gene. In the same way, comprehensive analyses of metabolite concentrations in mutants, providing "metabolic snapshots," can reveal functions when snapshots from strains deleted for unstudied genes are compared to those deleted for known genes. This approach to functional analysis, using comparative metabolomics, we call FANCY-an abbreviation for functional analysis by co-responses in yeast.


Assuntos
Metabolismo Energético/genética , Genoma Fúngico , Genômica/métodos , Mutação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Nucleotídeos de Adenina/metabolismo , Análise por Conglomerados , Genótipo , Hexosefosfatos/metabolismo , Fenótipo , Piruvatos/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento
8.
J Anim Sci ; 95(9): 4018-4029, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28992032

RESUMO

Three studies involving 352 grower pigs were conducted to determine the effects of dietary supplementation with multistrain spp. direct-fed microbial (DFM) and protease, alone or in combination, on growth performance, nutrient digestibility, blood characteristics, fecal microbiota, and noxious gas emissions, and to use a meta-analysis to increase the reliability of the findings. Treatments ( = 4) were set up as a 2 × 2 factorial design with 2 levels of protease (0 and 5.000/6.000 units/kilogram of feed [U/KG]) and 2 levels of DFM (0 and 1.5 × 10 colony forming units/gram of feed [CFU/G]), plus a protease + DFM combination. Pigs were housed in groups of 3 or 4/pen with 8 replicate pens/treatment. Experimental diets were fed for 42 d and feed intake and BW were measured weekly. Fecal samples were collected at d 42 and analyzed to determine apparent total tract digestibility (ATTD). Fecal counts of and coliforms, and noxious gas emissions were measured. Blood samples were taken by anterior vena cava puncture to measure blood urea nitrogen (BUN) and creatinine. Data from the 3 studies were pooled and analyzed as a 2 × 2 factorial using the Fit Model platform of JMP 11 (SAS Inst. Inc., Cary, NC). Means separation was determined using Tukey's honest significant difference test. The main effect of protease and DFM increased: BW at 42 d, overall ADG, and overall G:F compared to the control ( < 0.04). There were no interactions between protease and DFM ( > 0.05); however, the protease + DFM combination was the only treatment to improve ADG and G:F in all phases compared to the control. The main effect of protease increased ATTD of DM, nitrogen (N), and ADF ( < 0.04). The main effect of DFM increased ATTD of DM, N, GE, DE, ADF, and fat ( < 0.02). There was a trend for an interaction between protease and DFM for ATTD of GE and DE ( < 0.08) because the protease + DFM combination increased energy digestibility more than the additive effects of the protease and DFM alone. The main effects of protease and DFM decreased fecal ammonia emissions ( < 0.01), but the protease + DFM combination was the only treatment to decrease ammonia emissions compared to the control. In conclusion, the main effects of protease and DFM improved growth performance and nutrient digestibility compared to the control, but there was a greater additive effect of the protease + DFM combination on energy and N digestibility.


Assuntos
Bacillus/fisiologia , Suplementos Nutricionais , Microbiota , Peptídeo Hidrolases/metabolismo , Suínos/fisiologia , Amônia/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Nitrogênio da Ureia Sanguínea , Dieta/veterinária , Digestão , Fezes/microbiologia , Feminino , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Masculino , Nitrogênio/metabolismo , Peptídeo Hidrolases/sangue , Reprodutibilidade dos Testes , Glycine max , Suínos/sangue , Suínos/crescimento & desenvolvimento , Zea mays
9.
Poult Sci ; 96(12): 4287-4297, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29053809

RESUMO

The efficacy of two exogenous enzyme combinations and a multi-strain Bacillus probiotic (DFM) on the growth performance, nutrient digestibility, disappearance of non-starch polysaccharides (NSP) and gut microbial composition was investigated in broilers. One-day old Ross 308 chicks were assigned to 36 pens with 22 birds/pen and 6 pens/treatment (Experiment 1) or 36 cages with 8 birds/cage and 6 cages/treatment (Experiment 2). Treatment additives were added to nutritionally complete corn/soy based starter (d 1 to 21) and finisher (d 22 to 42) diets. Treatments included 1) a control diet containing 500 FTU/kg phytase (CTL), 2) CTL + xylanase (2,000 U/kg) and amylase (200 U/kg; XA), 3) CTL+XA + protease (4000 U/g; XAP), 4) CTL+DFM (150,000 cfu/g of 3 strains of Bacillus spp), 5) CTL+DFM+XA, and 6) CTL+DFM+XAP. Supplementation with DFM increased BW, BWG, and FI compared with the CTL (P < 0.05); XAP, but not XA, resulted in increased final BW, BWG and FI compared to the control (P < 0.05). XA and XAP improved apparent ileal digestibility (AID) of starch and fat on d 22 to 42 with XAP improving AMEn (by ∼82 kcal) compared with CTL birds (P < 0.01). DFM+XAP improved apparent ileal digestible energy (AIDE), AID of fat and starch on d 22 to 42, and additionally had a greater than additive effect on AIDE and AMEn. Supplementation with DFM+XAP reduced the ileal and total tract flow of insoluble arabinose and additionally total tract flow of soluble and insoluble xylose and total galactose (P < 0.05); similar effects of XA+DFM were not seen or were lower in magnitude, suggesting that the protease component plays an important role in increasing the availability of NSP for hydrolysis. Supplementation with DFM alone did not affect gut bacterial populations, but XA and XAP reduced numbers of Campylobacter species (by > 2.5 log cfu/g; P < 0.001) and Bacteroides (P < 0.02) in the cecum compared with CTL birds.


Assuntos
6-Fitase/metabolismo , Galinhas/fisiologia , Digestão/efeitos dos fármacos , Endo-1,4-beta-Xilanases/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Polissacarídeos/metabolismo , Probióticos/metabolismo , 6-Fitase/administração & dosagem , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Bacillus/química , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Suplementos Nutricionais/análise , Endo-1,4-beta-Xilanases/administração & dosagem , Probióticos/administração & dosagem , Distribuição Aleatória
10.
Poult Sci ; 96(9): 3239-3245, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28419372

RESUMO

The effects of adaptation (AD) to xylanase-supplemented diets on nutrient and fiber utilization in 21-d-old broilers were investigated. Six treatments, arranged in two levels of AD (starting at d 0 or d 14 of age) and three levels of xylanase (0 or 2,500 or 5,000 xylanase units/kg feed) were used. All diets had 500 phytase U/kg and 0.3% TiO2 as indigestible marker. A total of 384 d old male broiler (Ross 308) chicks were divided into two groups. The first group was assigned on weight basis to 24 cages (8 chicks per cage) and randomly allocated to the diets from d 0. Birds in the second group were reared on a commercial starter diet in the same room for 13 d. On d 14, the birds were individually weighed, assigned on weight basis to 24 cages (8 chicks per cage), and randomly allocated to the diets. Birds had free access to experimental diets and water. Excreta samples were collected from d 18 to 21. On d 21, all birds were euthanized to access ileal digesta. There was no interaction (P > 0.05) between AD and xylanase on the apparent ileal digestibility (AID) and apparent retention (AR) of components. The main effect of AD was such that the birds exposed to diets for 7 d (d 14 to 21) had higher (P < 0.01) AID of energy than those exposed for 21 d (d 0 to 21). In contrast, birds exposed to diets for 21 d had higher (P < 0.05) AMEn and AR of neutral detergent fiber. Xylanase improvements (P < 0.01) in the AID of energy and AMEn were dose dependent and coincided with linear improvements (P < 0.05) in the AID of nitrogen, fat, and starch. In conclusion, xylanase improvements on retention of fiber and nutrients were independent of AD (7 or 21 d) suggesting that the xylanase effects are not transitional. Greater retention of fiber with longer AD is suggestive of possible microbial adaptation.


Assuntos
Galinhas/fisiologia , Fibras na Dieta/metabolismo , Digestão , Endo-1,4-beta-Xilanases/metabolismo , Metabolismo Energético , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Dieta/veterinária , Suplementos Nutricionais , Digestão/efeitos dos fármacos , Endo-1,4-beta-Xilanases/administração & dosagem , Metabolismo Energético/efeitos dos fármacos , Masculino , Fatores de Tempo , Triticum/química
11.
J Anim Sci ; 95(7): 3068-3078, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28727078

RESUMO

The present study was conducted to determine the effect of flaxseed meal and oat hulls supplementation on growth performance, apparent total tract digestibility (ATTD) of fat, serum lipids, and concentrations of VFA, bile acids (BA), and neutral sterols (NS) in digesta and feces in growing pigs. Forty-eight Genesus [(Duroc boar × Yorkshire-Landrace sows] barrows (25.0 ± 0.32 kg initial BW) were housed in pairs. Pigs were assigned to 1 of the 3 corn-soybean meal-based diets-a basal corn-soybean meal-containing diet (control), a flaxseed meal-containing diet (FM), or an oat hulls-containing diet (OH)-in a completely randomized design. All diets were formulated to be isoenergetic and to contain similar standardized ileal digestible AA contents and meet other nutrient requirements for growing pigs. The experiment lasted for 28 d. Average daily feed intake; ADG; G:F; ATTD of fat, serum lipids, and digesta; and fecal VFA, BA, and NS concentrations were determined. Pigs fed the control or OH had greater final BW ( < 0.001), ADFI ( = 0.005), and ADG ( < 0.001) than FM-fed pigs. The ATTD of fat in the FM was lowest at 70.1% followed by 79.2% in OH and was greatest at 92.4% in the control ( = 0.020). Total serum cholesterol content was 2.25 and 1.99 mmol/L and lower ( < 0.001) in pigs fed FM and OH, respectively, than the 2.36 mmol/L in pigs fed the control. Pigs fed the FM and OH had greater ileal and cecal total VFA ( < 0.001), ileal deoxycholic acid ( < 0.01), and cecal ( < 0.001) and fecal cholesterol ( = 0.002) concentrations than those fed the control. Pigs fed the FM excreted more fecal lithocholic acid ( = 0.002) and ursodeoxycholic acid ( = 0.001) compared with those that consumed the control and OH. The concentrations of coprostanol in cecal digesta ( < 0.001) and feces ( = 0.011) were higher in pigs fed the FM and OH than in pigs fed the control. In conclusion, feeding flaxseed meal and oat hulls induced intestinal fermentation; however, the former depressed growth performance whereas the latter did not have any effect. Addition of flaxseed meal and oat hulls in growing pig diets reduced fat digestibility and serum cholesterol and stimulated malabsorption of primary BA and excretion of secondary BA and NS.


Assuntos
Avena , Linho , Suínos/fisiologia , Ração Animal , Animais , Ácidos e Sais Biliares/análise , Dieta/veterinária , Fibras na Dieta , Ácidos Graxos Voláteis/análise , Fezes/química , Fermentação , Trato Gastrointestinal/metabolismo , Masculino , Glycine max , Esteróis/análise , Suínos/crescimento & desenvolvimento , Zea mays
12.
Poult Sci ; 96(2): 388-396, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27444448

RESUMO

Effects of substituting cornstarch with D-xylose on growth performance, nutrients digestibility, serum metabolites, and expression of select hepatic genes involved in glucose and lipid metabolism were investigated in broiler chickens. A total of 360 one-day-old male Ross chicks were fed 3 diets (n = 24; 5 chicks/cage) for 21 days. A control corn-soybean meal-based diet with 25% cornstarch was formulated to meet specifications. Two additional diets were formulated by substituting cornstarch with 5 or 15% D-xylose w/w. Growth performance and digestibility by index method were determined in 12 replicate cages. Birds in these replicates had free access to feed and water, the BW and feed intake (FI) were monitored weekly and the excreta samples were collected on d 18 to 20. The other 12 replicates were used for blood and liver sampling by serial slaughter. On d 18, baseline (t0) birds were sampled following a 12 h overnight fasting and birds allowed 30 min access to the feed; samples were subsequently taken at 60, 120, 180, 240, and 300 min post feeding. Serum metabolites (glucose, xylose, and insulin) were assayed at all time points, whereas expression of hepatic transcripts was evaluated at zero, 180 and 300 min. Xylose linearly reduced (P < 0.05) FI, BWG, gross energy digestibility, and feed conversion ratio (FCR) but increased (P < 0.05) serum xylose level. Serum glucose and insulin levels were higher (P < 0.05) in the post-fed state compared with baseline, irrespective of treatments. There was an interaction (P < 0.05) between diet and sampling time on the expression of hepatic genes. At t0, xylose linearly increased (P < 0.05) the expression of pyruvate carboxylase, Acetyl Co-A acethyltransferase 2 (ACAT2), and glucose transporter 2. Xylose linearly reduced (P < 0.05) the expression of ACAT2 at 300 min post feeding. In conclusion, 5% or more xylose reduced growth performance and utilization of nutrients linked to hepatic enzymes and transcription factors involved in glucose and lipid metabolism.


Assuntos
Proteínas Aviárias/genética , Galinhas/fisiologia , Glucose/metabolismo , Metabolismo dos Lipídeos , Fatores de Transcrição/genética , Xilose/metabolismo , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Proteínas Aviárias/metabolismo , Análise Química do Sangue/veterinária , Galinhas/genética , Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Fígado/enzimologia , Fígado/metabolismo , Masculino , Distribuição Aleatória , Amido/metabolismo , Fatores de Transcrição/metabolismo
13.
J Anim Sci ; 95(1): 308-319, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28177388

RESUMO

Effects of a -based direct-fed microbial (DFM) on growth performance, plasma tumor necrosis factor ɑ (TNFɑ), relative gene expression, and intestinal VFA concentrations in weanling pigs fed low- or high-fiber diets were evaluated. Two hundred pigs (initial BW: 6.31 ± 0.73 kg) were allotted to 1 of 4 dietary treatments (5 pigs per pen and 10 pens per treatment). Treatments were arranged in a 2 × 2 factorial design with 2 diet types [low-fiber (LF) or high-fiber (HF)] and 2 concentrations of DFM (0 or 60 g DFM/t of feed). The DFM contained 1.5 × 10 cfu/g and was obtained from Danisco Animal Nutrition-DuPont Industrial Biosciences, Marlborough, UK. Phase 1 diets were fed for 2 wk post-weaning and phase 2 diets were fed over the following 29 d. Low fiber diets contained corn and soybean meal as main ingredients and HF diets contained corn, soybean meal, corn distillers dried grains with solubles (7.5 and 15.0% in phase 1 and 2, respectively), and wheat middlings (10.0%). Pigs and feed were weighed at the start and at the end of each phase, and ADG, ADFI, and G:F were calculated. At the conclusion of phase 2, blood was collected from 1 pig per pen and 1 pig per pen was sacrificed. Cecum and rectum contents were analyzed for VFA, and tissue samples were collected from the ileum, cecum, rectum, and liver to determine expression of genes related to absorption and metabolism of VFA using quantitative reverse transcription-PCR. Results indicated that feeding HF diets reduced ( ≤ 0.05) ADFI and ADG of pigs compared with feeding LF diets. Pigs fed DFM diets had improved ( ≤ 0.05) G:F compared with pigs fed non-DFM diets. Pigs fed LF diets had greater ( ≤ 0.05) BW at the end of phase 2 compared with pigs fed HF diets. The concentration of VFA in rectum contents was greater ( ≤ 0.05) in pigs fed LF diets than in pigs fed HF diets. The expression of in the rectum of pigs fed HF diets was greater ( ≤ 0.05) than for pigs fed LF diets, and pigs fed DFM-containing diets had an increased ( ≤ 0.05) expression of in the liver. Pigs fed HF diets had greater ( ≤ 0.05) concentrations of urea N in plasma compared with pigs fed LF diets, but dietary fiber and DFM had no effect on plasma concentration of TNF-ɑ. In conclusion, the -based DFM improved overall G:F of weanling pigs, but pigs fed LF diets had greater final BW than pigs fed HF diets.


Assuntos
Ração Animal/análise , Bacillus/fisiologia , Fibras na Dieta/administração & dosagem , Ácidos Graxos Voláteis/metabolismo , Regulação da Expressão Gênica/fisiologia , Suínos/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Fibras na Dieta/farmacologia , Feminino , Masculino , Probióticos
14.
Animal ; 11(2): 209-218, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27412081

RESUMO

A 26-day trial with 18 Pietrain×(Landrace×Duroc) pigs was conducted to investigate the effect of two dose levels of a specifically selected Bacillus spp. direct-fed microbial (DFM) product, on the emission of environmentally harmful gasses (methane, ammonia and hydrogen sulphide) from manure. Pigs were assigned to one of three treatments in a randomized complete block design according to their sex and initial BW. Each treatment contained three replications with two pigs per pen. The test treatments included a Bacillus spp. DFM containing 3×108 colony-forming unit/g, added at a low (250 mg/kg) and high (500 mg/kg) dose to an antibiotic free high fibre-based diet, and a non-supplemented control diet. Manure from pigs fed with the supplemented diets emitted lower amounts of atmospheric contaminants. The most significant reduction was observed with low DFM supplementation, in which methane and ammonia volatilization decreased (P40% and 50%, respectively, on fresh weight basis in relation to the control. Microbiome analysis of manure by high through put sequencing techniques on eubacterial and archaeal 16S rRNA genes highlighted the complex interactions between indigenous gut microflora and inoculated Bacillus spp. The tested Bacillus DFM could be considered as a best available technique in reducing the environmental impacts of growing pigs fed with high fibre-based diets.


Assuntos
Poluentes Atmosféricos/metabolismo , Ração Animal/análise , Bacillus , Fibras na Dieta/administração & dosagem , Esterco/análise , Suínos/fisiologia , Poluentes Atmosféricos/química , Amônia/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta , Fibras na Dieta/análise , Suplementos Nutricionais/análise , Fezes , Gases/análise , Masculino , Microbiota , Probióticos/administração & dosagem
15.
J Perinatol ; 37(11): 1220-1223, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28880260

RESUMO

OBJECTIVE: To analyze reasons for low enrollment in a randomized controlled trial (RCT) of the effect of hydrocortisone for cardiovascular insufficiency on survival without neurodevelopmental impairment (NDI) in term/late preterm newborns. STUDY DESIGN: The original study was a multicenter RCT. Eligibility: ⩾34 weeks' gestation, <72 h old, mechanically ventilated, receiving inotrope. Primary outcome was NDI at 2 years; infants with diagnoses at high risk for NDI were excluded. This paper presents an analysis of reasons for low patient enrollment. RESULTS: Two hundred and fifty-seven of the 932 otherwise eligible infants received inotropes; however, 207 (81%) had exclusionary diagnoses. Only 12 infants were randomized over 10 months; therefore, the study was terminated. Contributing factors included few eligible infants after exclusions, open-label steroid therapy and a narrow enrollment window. CONCLUSION: Despite an observational study to estimate the population, very few infants were enrolled. Successful RCTs of emergent therapy may require fewer exclusions, a short-term primary outcome, waiver of consent and/or other alternatives.


Assuntos
Cardiotônicos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Hidrocortisona/uso terapêutico , Seleção de Pacientes , Estado Terminal/terapia , Método Duplo-Cego , Término Precoce de Ensaios Clínicos , Cardiopatias Congênitas/tratamento farmacológico , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Consentimento Livre e Esclarecido , Transtornos do Neurodesenvolvimento/prevenção & controle
16.
J Perinatol ; 36(12): 1106-1111, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27583387

RESUMO

OBJECTIVE: Data from multiple clinical trials, mostly conducted outside the US, indicate that probiotic prophylaxis is an effective intervention for prevention of necrotizing enterocolitis (NEC) in preterm infants. Probiotics are routinely used in many countries. However, in the US, probiotic use in preterm infants is limited (6.7% of very low birth weight (VLBW) infants in the US were exposed to probiotics in 2014, Vermont Oxford Network (VON)). Probiotic products are often considered in 'generic' terms, but considerable variation exists between commercially available probiotics in terms of their quantity and quality. The study objectives were to identify the probiotic products used in VLBW infants within the US, and to determine whether their use was supported by reliable evidence. STUDY DESIGN: A phone survey of all neonatal intensive care units (NICU) participating in VON within the US was conducted between May and September 2015 to identify NICUs that are using probiotics in VLBW infants. Data was collected regarding specific probiotic brands, timing, dose and duration of probiotic use. An evidence based literature search, limited to randomized controlled trials in VLBW infants, was conducted to determine whether the use of identified probiotics were supported by reliable evidence. RESULTS: There was a 70.3% (500/711) response rate to the phone survey. During the survey period, 14.0% of NICUs were using probiotics in VLBW infants (70/500). Probiotics were routinely given to all VLBW infants in 8.8% (44/500) NICUs, while it was given in selected VLBW infants in 5.2% (26/500) of NICUs. The common indications for selective use of probiotics were feeding intolerance and antibiotic use. Sixteen commercial probiotics products were identified through the phone survey. Probiotic products most commonly used were Culturelle (27.1%), Biogaia (14.3%), Gerber Soothe (14.3%) and Florababy (8.6%). The literature search identified evidence that evaluated 4/16 probiotic products identified (Culturelle, Align, Biogaia and ABC Dophilus). Only ABC Dophilus was reported to have a protective effect against NEC, but is used sparingly in US NICUs (2.9%). CONCLUSIONS: The probiotics use in VLBW infants within the US is increasing, but is still limited. There was no evidence for safety or efficacy of 90% of the probiotics currently used in US NICUs, and therefore, caution is warranted.


Assuntos
Enterocolite Necrosante/prevenção & controle , Recém-Nascido de muito Baixo Peso , Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Probióticos/uso terapêutico , Estudos Transversais , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Ensaios Clínicos Controlados Aleatórios como Assunto , Risco , Inquéritos e Questionários , Estados Unidos
17.
J Anim Sci ; 94(9): 3760-3770, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27898890

RESUMO

Information on effects of supplementing fibrous diets with exogenous enzymes on nutrient absorption and energetic demands of visceral organs is scarce. Therefore, this study investigated the effects of supplementing a high-fiber (HF) diet with a multi-enzyme cocktail (MC) on net glucose and lactate portal fluxes, insulin production, and O consumption by the portal-drained viscera (PDV) and whole animal in growing pigs. The MC supplied (analyzed values) 5,397 U of xylanase, 162 U of ß-glucanase, and 2,000 U of protease per kg of diet, and guaranteed minimum activities of 1,000 U of α-amylase and 25 U of pectinase per kg of diet. Three isocaloric-nitrogenous diets based on corn and soybean meal with 0% (control) or 30% distillers' dried grains with solubles (DDGS; 1:1 corn and wheat mixture; HF) and HF supplemented with MC (HF + MC) were used. Five gilts (initial BW = 22.8 ± 1.6 kg) fitted with permanent catheters in the portal vein and carotid artery (for blood sampling), and ileal vein (to infuse para-amino hippuric acid to measure blood flow rate) were fed the 3 diets at 4% BW once daily at 0900 h for 7 d in a replicated 3 × 3 Latin square design. On d 7, pigs were placed in an open-circuit indirect calorimeter to measure whole-animal O consumption and sample blood for 7 h postprandial. Net glucose and insulin production were calculated from portal-arterial differences × portal blood flow, and PDV O consumption was calculated as arterial-portal O differences × portal blood flow. Diet had no effect on postprandial whole-animal O consumption, flow rate, and lactate flux. In addition, diet had no effect on overall mean postprandial PDV O consumption. Pigs fed control had greater ( < 0.05) portal insulin and glucose fluxes, from 90 to 300 min and net glucose flux from 90 to 240 min postprandial. However, pigs fed control and HF + MC had similar net glucose flux, which was greater ( < 0.05) than in pigs fed the HF diet. In conclusion, diets did not affect the energetic demand of the PDV but adding MC to the HF diet improved postprandial net glucose portal flux in growing pigs.


Assuntos
Ração Animal/análise , Fibras na Dieta , Suplementos Nutricionais , Glucose/metabolismo , Ácido Láctico/metabolismo , Consumo de Oxigênio , Suínos/fisiologia , Animais , Calorimetria Indireta/veterinária , Dieta/veterinária , Feminino , Hidrolases , Insulina/metabolismo , Secreção de Insulina , Nitrogênio/metabolismo , Veia Porta/fisiologia , Período Pós-Prandial/fisiologia , Glycine max , Vísceras/fisiologia , Zea mays
18.
J Anim Sci ; 94(9): 3771-3785, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27898914

RESUMO

The present study investigated the effects of adding a multi-enzyme cocktail (MC) to a high-fiber diet on net portal-drained viscera (PDV) fluxes of essential AA (EAA), volatile fatty acids (VFA), and blood urea-N (BUN) in growing pigs. Five female pigs (22.8 ± 1.6 kg BW), with catheters in the portal vein, ileal vein, and carotid artery, were fed 3 isocaloric-nitrogenous diets at 4% of their BW once daily at 0900 h for 7 d in a replicated 3 × 3 Latin square design. The diets contained corn and soybean meal with 0% (control) or 30% distillers' dried grains with solubles (DDGS; HF) produced from a 1:1 mixture of wheat and corn. The third diet was supplemented with MC in addition to the 30% DDGS (HF + MC). The MC supplied (analyzed values) 5,397 U of xylanase, 162 U of ß-glucanase, and 2,000 U of protease and guaranteed minimum activities of 1,000 U of α-amylase and 25 U of pectinase per kg of diet. On d 7, para-amino hippuric acid was infused into the ileal vein (to measure flow rate), and blood was sampled from the portal vein and carotid artery for 7 h after feeding to assay EAA, urea-N, and VFA. Portal absorption of nutrients was derived by multiplying the porto-arterial plasma concentration differences by portal vein blood flow. Diet had no effect on postprandial portal vein plasma flow rate and net BUN flux, but portal BUN tended to be lower ( = 0.070) and arterial BUN was lower ( 0.05) over the 7 h in pigs fed control. Postprandial portal Arg, Ile, Leu, Trp, and Val or net fluxes were lower ( 0.05) in HF-fed pigs from 30 to 240 min than control-fed pigs and MC supplementation tended (0.05 ≤ ≤ 0.10) to or improved ( 0.05) portal appearances of those AA, but not their fluxes. Control-fed pigs had higher ( 0.05) net portal fluxes of most EAA and pigs fed HF + MC had higher ( 0.05) Lys, and similar Met and Phe net portal fluxes were compared with control-fed pigs. Portal VFA was not affected by diet. However, total portal VFA flux was lower ( 0.05) in the HF-fed pigs than in the control pigs. The MC supplementation improved the total portal VFA flux, although it did not improve arterial VFA concentration relative to the HF diet. In conclusion, supplementing the HF diet with MC improved net portal appearance of some EAA and fluxes of total VFA, whereas fluxes of EAA did not change. The HF diet increased EAA demand by the PDV, but MC addition was not able to reduce this demand.


Assuntos
Aminoácidos Essenciais/metabolismo , Ração Animal/análise , Fibras na Dieta , Suplementos Nutricionais , Ácidos Graxos Voláteis/metabolismo , Suínos/fisiologia , Animais , Nitrogênio da Ureia Sanguínea , Dieta/veterinária , Feminino , Hidrolases , Nitrogênio/metabolismo , Veia Porta/fisiologia , Período Pós-Prandial/fisiologia , Glycine max , Triticum , Ureia/metabolismo , Zea mays
19.
Eur J Clin Nutr ; 70(5): 642-4, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26838593

RESUMO

There are no standardised serving/portion sizes defined for foods consumed in the European Union (EU). Typical serving sizes can deviate significantly from the 100 g/100 ml labelling specification required by the EU legislation. Where the nutritional value of a portion is specified, the portion size is determined by the manufacturers. Our objective was to investigate the potential for standardising portion sizes for specific foods, thereby ensuring complementarity across countries. We compared portion size for 156 food items measured using a food frequency questionnaire across the seven countries participating in the Food4me study. The probability of consuming a food and the frequency of consumption differed across countries for 93% and 58% of the foods, respectively. However, the individual country mean portion size differed from the average across countries in only 16% of comparisons. Thus, although dietary choices vary markedly across countries, there is much less variation in portion sizes. Our results highlight the potential for standardisation of portion sizes on nutrition labels in the EU.


Assuntos
Inquéritos sobre Dietas/estatística & dados numéricos , Comportamento Alimentar , Rotulagem de Alimentos/normas , Alimentos/estatística & dados numéricos , Política Nutricional , Tamanho da Porção/estatística & dados numéricos , Ingestão de Alimentos , Europa (Continente) , Rotulagem de Alimentos/estatística & dados numéricos , Humanos , Valor Nutritivo , Tamanho da Porção/normas
20.
Pediatrics ; 84(5): 808-14, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2797976

RESUMO

The long-term outcome of very low birth weight (VLBW) infants with necrotizing enterocolitis has been reported to be similar to that of other VLBW infants. To examine the influence of disease severity on outcome, the growth and neurodevelopment of survivors of necrotizing enterocolitis were evaluated when the babies were 20 months' corrected age. Between 1975 and 1983, 1506 VLBW infants were admitted to the hospital, and necrotizing enterocolitis developed in 84 (5.6%). Forty infants (48%) survived to be 20 months' corrected age, and complete follow-up data were available for 36. Survivors were classified by modified Bell's criteria into four groups by increasing severity of disease; 13 had mild necrotizing enterocolitis (stage IIA, IIB), and 23 had severe necrotizing enterocolitis (stage IIIA, IIIB). The 36 survivors were compared with 766 surviving VLBW infants without necrotizing enterocolitis. There were no perinatal or socioeconomic differences between groups. Compared with infants with stage II necrotizing enterocolitis at 20 months, infants with stage III necrotizing enterocolitis had a higher rate of subnormal body weight (39% vs 15%) and subnormal head circumference (30% vs 0%). Thirty-three percent of necrotizing enterocolitis survivors had significant neurodevelopmental impairment; the majority of impaired infants (10 of 12) were survivors of stage III necrotizing enterocolitis. These findings highlight the importance of continued evaluations for medical and neurodevelopmental sequelae.


Assuntos
Enterocolite Pseudomembranosa/patologia , Desenvolvimento Infantil , Pré-Escolar , Enterocolite Pseudomembranosa/complicações , Enterocolite Pseudomembranosa/terapia , Seguimentos , Crescimento , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Inteligência , Doenças do Sistema Nervoso/etiologia
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