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Microbiote intestinal et développement de l’obésité : une approche par métagénomique et métabolomique du concept de répondeur et non-répondeur / Gut microbiota and obesity development : metagenomic and metabolomic strategies of the responder and non-responder conceptBally, Pascal 28 May 2015 (has links)
Au cours des dernières années, de nombreuses études ont porté sur les relations entre le microbiote intestinal et l'obésité. Des groupes bactériens ont été incriminés et des hypothèses proposées mais les mécanismes liant microbiote et obésité restent en grande partie inconnus. Le microbiote intestinal est constitué de plusieurs centaines d’espèces et est spécifique de chaque individu. Récemment, il a été révélé l’implication potentielle de ce microbiote dans le développement de l’obésité. Lors d’une étude précédente, notre équipe a ainsi montré que les souris sans germes (dites « axéniques ») sont résistantes à l’obésité et aux désordres métaboliques induits par un régime hypercalorique (Roy et al. 2012). Par ailleurs, nous avons observé que certaines souris conventionnelles soumises à un tel régime développent une obésité et une insulinorésistance importantes (phénotype dit répondeur) tandis que d'autres restent minces et tolérantes au glucose (phénotype dit non répondeur) indépendamment de la quantité de nourriture consommée. Les mécanismes expliquant cette hétérogénéité de phénotype sont actuellement peu connus. Ce projet de thèse vise donc à élucider les mécanismes liant le microbiote intestinal au développement de l'obésité et des désordres associés en partant du principe que l'hétérogénéité (en termes de composition et de fonctions) du microbiote intestinal, spécifique de chaque individu (aussi bien chez l'homme que chez le rongeur), joue un rôle dans ces réponses différentes à un même régime hypercalorique. Pour ce faire, des souris conventionnelles ont reçu un régime contrôle ou un régime hyperlipidique pendant 12 semaines. A l’issu de ce régime, des souris ont été sélectionnées en tant que répondeuses ou non-répondeuses Une approche par métagénomique à partir d’échantillons fécaux prélevés avant et après régime hyperlipidique et issus des souris répondeuses et non-répondeuses ont été analysés. Les profils de microbiotes avant et après régime hyperlipidique ont été comparés afin de déterminer les effets de ce régime sur le microbiote intestinal. De plus, le profil du microbiote des souris répondeuses a été comparé à celui des souris non-répondeuses afin de détecter des espèces bactériennes, des gènes ou des voies métaboliques sous- ou sur-représentés dans les deux phénotypes. Par ailleurs, des échantillons de fèces, d’urine et de plasma prélevés avant et après le régime hyperlipidique ont été analysés par métabolomique et nous avons ainsi analysé les fluctuations métaboliques induites par l’effet du régime. L’ensemble de ces travaux a eu pour but d’identifier s’il existe un microbiote de prédisposition au développement ou à la résistance du développement d’une obésité induite. Au cours de ce projet de thèse nous avons utilisé l’approche de métagénomique à partir d’échantillon fécaux afin d’identifier les profils du microbiote intestinal des souris NR et des souris R avant et après régime hyperlipidique en vue de mesurer l’impact de ce type de régime sur le microbiote, et surtout de détecter les espèces bactériennes, les gènes ou les voies métaboliques potentiellement sous- ou sur-représentés dans les deux phénotypes. D’autre part, l’approche de métabolomique a été utilisée sur des échantillons d’urine, de fèces et de plasma avant et après régime afin de visualiser les fluctuations métaboliques induites par l’effet du régime d’une part et d’identifier les métabolites (biomarqueurs) associés à chacun des phénotypes d’autre part. / In recent years, numerous studies have examined the relationship between the gut microbiota and obesity. Bacterial groups have been incriminated but the mechanisms linking microbiota and obesity remain largely unknown. Intestinal microbiota consists of several hundred species and is specific for each individual. Recently, it was revealed that the potential contribution of microbiota in the development of obesity. In a previous study, our team has shown that mice without germs (called "germ-free") are resistant to obesity and metabolic disorders induced by a high calorie diet (Roy et al. 2012). Furthermore, we observed that certain conventional mice subjected to such a plan develop an important obesity and insulin resistance (responder phenotype) while others remain thin and glucose tolerant (non responder phenotype) regardless of the amount of food consumed. The mechanisms explaining this phenotype heterogeneity are currently poorly known. This PhD project aims to elucidate the mechanisms linking the intestinal microbiota in the development of obesity and disorders associated with the assumption that heterogeneity (in terms of composition and functions) of the intestinal microbiota, specific for each individual ( both in humans than in rodents), plays a role in these different responses to the same high-fat diet. To do this, conventional mice received control diet or a high fat diet for 12 weeks. At the end of this diet, mice were selected as a responder or non-responder A metagenomics approach from fecal samples taken before and after high fat diet and from responder and non-responder mice were analyzed. Microbiota profiles before and after fat diet were compared to determine the effects of this diet on the intestinal microbiota. In addition, the profile of the microbiota of responder mice was compared to that of non-responder mice in order to detect bacterial species, genes or pathways under- or over-represented in both phenotypes. Furthermore, samples of feces, urine and plasma collected before and after fat diet were analyzed by metabolomics and we have analyzed the metabolic changes induced by the effect of diet. All of this work has been aimed to identify if there is a predisposition microbiota to the development or the resistance of induced obesity. In this PhD project we used the metagenomic approach from fecal sample to identify the profiles of the intestinal microbiota in mice NR and R mice before and after fat diet in order to measure the impact of this type of diet on the microbiota, and especially to detect bacterial species, genes or metabolic pathways potentially under- or over-represented in both phenotypes. On the other hand, the approach of metabolomics has been used on samples of urine, feces and plasma before and after diet in order to visualize the metabolic changes induced by the effect of diet on the one hand and to identify metabolites (biomarkers) associated with each other hand phenotypes.
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Efeito das proteínas do soro do leite bovino sobre alterações metabólicas causadas por uma dieta hiperlipídica no camundongo C57BL/6 : disbiose intestinal, resposta inflamatória e parâmetros associados / intestinal dysbiosis, inflammatory response and associated parameters : Obesidade; Proteínas do soro do leite; Inflamação; Microbiota intestinal; Dieta hiperlipídicaMonteiro, Naice Eleidiane Santana, 1990- 27 August 2018 (has links)
Orientadores: Jaime Amaya-Farfan, Fernanda de Pace / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-27T02:35:33Z (GMT). No. of bitstreams: 1
Monteiro_NaiceEleidianeSantana_M.pdf: 1835989 bytes, checksum: ec62cf398adabcdca614249ae2d4692b (MD5)
Previous issue date: 2015 / Resumo: Caracterizada como um dos mais importantes problemas que a saúde pública enfrenta atualmente no Brasil e no mundo, a obesidade está associada a um quadro de inflamação subclínica, que predispõe à resistência à insulina e ao desenvolvimento de diabetes mellitus, além de representar fator etiológico para diversas outras doenças crônicas não transmissíveis. Sabendo da importância que os alimentos com propriedades bioativas podem ter no tratamento da obesidade é que a utilização das proteínas do soro do leite na dieta vem sendo alvo de diversos estudos, devido aos benefícios que podem trazer à saúde humana. Dentre as propriedades da whey protein, citam-se a capacidade de regular a função imune, atuar como agente antimicrobiano, estimular a síntese de proteína muscular, suprimir o apetite e atuar na redução da gordura corporal, além das propriedades de aumentar a expressão gênica de proteínas anti-estresse (HSPs) e de ativar o transportador de glicose GLUT4, ambas descobertas pelo nosso grupo da FEA. O presente estudo teve como objetivo investigar o impacto que as proteínas do soro do leite, seja na sua forma íntegra ou na forma hidrolisada, possam exercer sobre a homeostase e a proteção do organismo de camundongos, contra os danos causados por uma dieta hiperlipídica. Para alcançar este objetivo, 34 camundongos C57BL/6 recém-desmamados foram divididos em quatro grupos de forma aleatória e alimentados com as seguintes dietas: grupo controle normolipídico (AIN93-G), grupo controle hiperlipídico (HFCAS), grupo hiperlipídico com substituição da caseína pela proteína do soro de leite concentrada (HFWPC), e grupo hiperlipídico, com adição da proteína do soro do leite hidrolisada (HFWPH), por 9 semanas. Os camundongos foram acompanhados quanto ao consumo alimentar e ganho de peso por meio de avaliação poderal em dias alternados, parâmetros bioquímicos e de endotoxemia avaliados por técnicas convencionais, biomarcadores inflamatórios analisados por western blot, além da avaliação do perfil histopatológico do fígado e do estudo metagenômico da microbiota intestinal. Os resultados demonstraram que alimentação com a formulação contendo whey protein, em ambas as formas, por 9 semanas, não diminuiu ganho de peso em comparação aos demais tratamentos, mas foi efetiva em reverter a disbiose causada pela dieta gordurosa, reduzir o processo inflamatório para níveis indistinguíveis do controle, em atenuar a infiltração gordurosa no tecido hepático, além de modular a microbiota intestinal. A caseína não mostrou tais propriedades / Abstract: Recognized as one of the most important issues currently facing public health in Brazil and in the world, obesity is associated to a subclinical inflammation framework, which predisposes to insulin resistance and the development of diabetes mellitus, in addition to representing an etiological factor for several other chronic diseases. Owing to the bioactive properties that the milk whey proteins may have on human health, such as the ability to regulate immune function, act as an antimicrobial agent, stimulate protein synthesis, suppress appetite thus helping to reduce body fat, besides the two newly discovered functions from our laboratory regarding the up-regulation of protective HSPs and activation of the glucose transporter 4 (GLUT4), it is thought that these proteins may also have anti-inflammatory action and, therefore, this study was designed to investigate the impact that whey protein, either in its normal form or in the hydrolyzed form, may exert on homeostasis protecting the mouse from the adverse effects of a high-fat diet. To accomplish this, 34 C57BL/6 male mice were randomly divided into four groups that received the following diets for 9 weeks: Normolipidic control (AIN93-G), Hyperlipidic control (HFCAS), Hyperlipidic with whey protein concentrate instead of casein (HFWPC) and a Hyperlipidic group with hydrolyzed whey protein (HFWPH) as the only source of protein. Diet intake and weight gain were monitored and recorded every other day. Biochemical parameters and endotoxemia were evaluated using commercial kits, and inflammatory biomarkers were analyzed by western blotting, besides the evaluation of histopathological liver profile and metagenomic study of the intestinal microbiota. The results showed that feeding the formulation contendowheyprotein, in both its forms, for 9 weeks, not decreased weight gain compared to the other treatments, but was effective in reversing dysbiosis caused by high-fat diet, reduce inflammation to levels indistinguishable control and mitigate the fatty infiltration of the casein hepático, in addition to modulate the gut microbiota. Casein did not show such properties / Mestrado / Nutrição Experimental e de Alimentos / Mestra em Alimentos e Nutrição
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Efeito do consumo de probióticos em fatores associados com progressão da doença renal crônica e risco cardiovascularMoreira, Thais Rodrigues January 2018 (has links)
Introdução: O trato gastrointestinal humano é composto por uma comunidade microbiana diversificada que atua no controle da saúde. Estudos recentes demonstraram que o equilíbrio da microbiota intestinal é afetado na doença renal crônica (DRC), ocasionando o quadro de disbiose intestinal. Estes estudos sugeriram uma associação da disbiose intestinal com complicações metabólicas como acúmulo de toxinas urêmicas, progressão da DRC, inflamação e risco cardiovascular. Diante disso, medidas com o objetivo de restaurar o equilíbrio da microbiota intestinal são sugeridas, tais como a ingestão oral de probióticos, mas poucos estudos têm abordado o efeito destes suplementos na progressão da DRC e no risco cardiovascular destes pacientes. Objetivo: Avaliar o efeito do consumo de probióticos em fatores associados com progressão da DRC e risco cardiovascular de pacientes com DRC. Material e métodos: Trata-se de um estudo clínico controlado por placebo registrado no Clinical Trials NCT03400228. O estudo incluiu 30 pacientes adultos com DRC nos estágios 3 a 5 não em diálise, com função renal estável e proteinúria igual ou superior a 500 mg. A coleta de dados ocorreu entre novembro de 2015 até dezembro de 2017. O protocolo do estudo constou de período de washout de 4 semanas e randomização dos pacientes para o grupo de intervenção (GI, suplemento com probiótico) ou para o grupo controle (GC, maltodextrina). Foi realizado avaliação basal e após 24 semanas de consumo de probiótico ou placebo. Todos os pacientes receberam a orientação de consumir 2 sachês por dia do probiótico ou do placebo (maltodextrina). Foram avaliadas variáveis demográficas, clínicas, nutricionais, hábito intestinal e exames laboratoriais com amostras sanguíneas e urinárias. Resultados: Dos 30 pacientes incluídos, 20 completaram as 24 semanas do estudo, sendo 10 no grupo intervenção e 10 no grupo placebo. Após o uso de probiótico houve aumento na taxa de filtração glomerular estimada (p<0,001) e diminuição nos níveis séricos de creatinina (p<0,001), ureia (p=0,015), proteína C reativa (p=0,03), hormônio da paratireóide (p=0,03) e potássio (p=0,012), em comparação ao grupo placebo. Os efeitos positivos do probiótico na taxa de filtração glomerular estimada e na diminuição dos níveis séricos de creatinina e ureia permaneceram após análise de regressão multivariada. Não houveram diferenças significativas nos parâmetros urinários entre os grupos. Sintomas de constipação (p<0,001) e consistência fecal (p=0,016) apresentaram melhora no grupo intervenção versus placebo. Conclusão: A suplementação de probióticos melhorou os marcadores de função renal e reduziu inflamação, além de auxiliar na melhora dos sintomas de constipação intestinal em pacientes com DRC. / Introduction: The human gastrointestinal tract is colonized by a diversified microbial community that acts in control of health. Recent studies have shown that intestinal microbiota balance is affected in chronic kidney disease (CKD) leading to intestinal dysbiosis. These studies have suggested association of intestinal dysbiosis with several metabolic disorders such as accumulation of uremic toxins, progression of CKD, inflammation and cardiovascular risk. Therefore, interventional measurement that improve intestinal microbiota balance are suggested such as supplementation of probiotics, however few studies evaluated the effect of these supplements on the progression of CKD and cardiovascular risk in CKD patients. Aim: The purpose of the study was to evaluate the effects of probiotic supplementation on the factors associated with progression of CKD and cardiovascular risk in patients with CKD. Desing and Methods: This was a randomized, double-blind, placebo-controlled study. Thirty patients with CKD stages 3 to 5 not on dialysis, with stable renal function and protein-creatinine ratio > 0.50 were included. Data collection was between November 2015 and December 2017. Study protocol was 4-week washout period, patients randomized to intervention group (IG, probiotic supplement) or control group (CG, maltodextrin), and follow for 24 weeks. Renal function, C-reactive protein (CRP), bone and mineral metabolism, nutritional, and lipid profile markers and intestinal habit were measured at baseline and 24 weeks of study. Results: From 30 patients included in this study, 20 completed the 24 study weeks, 10 in the TG and 10 in PG. After probiotic supplementation, there was increase in estimated glomerular filtration rate (p<0.001) and decrease in serum creatinine 8 (p<0.001), urea (p=0.015), C-reactive protein (p=0.030), parathyroid hormone (p=0.03), and potassium (p=0.012) levels compared to CG. The beneficials effects of probiotics on estimated glomerular filtration rate and serum creatinine, urea, and Creactive protein remained after multivariate linear regression. There were no significant differences in the urinary parameters between the two groups. Symptoms of constipation (p<0.001) and stool consistency (p=0.016) improved in IG compared to CG. Conclusion: Probiotic supplementation improved markers of renal function and reduced inflammation. In addition, it improved the symptoms of intestinal constipation in patients with CKD.
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Ecologia alimentar da toninha Pontoporia blainvillei (Cetacea) / Feeding ecology of franciscana dolphin Pontoporia blainvillei (Cetacea)Silva, Barbara Henning 20 December 2011 (has links)
Originalmente, a teoria de nicho ecológico fundamenta-se em indivíduos de uma espécie sendo ecologicamente equivalentes por utilizarem os recursos de forma similar. Portanto, o nicho de uma espécie é definido em termos do uso médio de recursos. Porém, a qualidade e abundância de recursos consumidos, sexo, idade ou morfotipo do consumidor influenciam o comportamento alimentar individual. Estudos recentes sobre forrageamento ótimo tem foco de interesse na variação interindividual no uso de recursos. Ao longo da sua área de distribuição são reconhecidas populações da toninha Pontoporia blainvillei (Cetacea) e no litoral paulista, possivelmente hajam três subpopulações dessa espécie: norte, centro e sul. Meu primeiro objetivo foi investigar se há variação na dieta entre essas três subpopulações de toninha. Adicionalmente, investiguei quais fatores entre sazonalidade, sexo e idade dos indivíduos poderiam estruturar a dieta em uma dessas subpopulações (central). Utilizei 58 indivíduos provenientes de captura acidental no litoral paulista, com representantes das regiões norte, centro e sul. A amostra incluiu juvenis e adultos de ambos os sexos, capturados em todas as estações do ano. Identifiquei as espécies nos conteúdos estomacais usando os otólitos de peixes e os bicos de lulas. Estimei o tamanho das presas utilizando regressões com as medidas dessas estruturas e investiguei a estruturação da dieta usando um índice de variação da dieta. Houve uma clara variação na dieta ente as subpopulações paulistas, possivelmente devido à diferença espacial na disponibilidade de presas. Para a subpopulação central não houve variação na dieta decorrente da sazonalidade ou do sexo. A ausência de variação sazonal pode ser devido à pouca alteração na abundância da principal presa, P. harroweri, no ambiente ao longo do ano. A ausência de variação decorrente do sexo pode ser devido a seleção de presa estar mais relacionada a características de corpo mole e fácil digestão e não ao tamanho da presa, sendo essa seleção comum para ambos os sexos. Indivíduos de idades diferentes possuem dietas distintas, com juvenis consumindo mais espécies que os adultos. Essa mudança de nicho alimentar pode ser devida ao período de aprendizado. Finalmente, mesmo descontando os efeitos da disponibilidade temporal e espacial de presas, do sexo e da idade, houve variação interindividual da dieta na subpopulação central. Somente estudos com marcadores isotópicos poderão investigar se essa variação é devida à especialização individual em toninhas / Ecological niche theory is originally based on the assumption that individuals of a species use similar resources and therefore are ecologically equivalents. Under this framework, the niche of the species can be defined in terms of average resource use. However, factors such as quality and quantity of prey resources in the environment, consumer gender, age or morphotype may influence the individual feeding behavior. Considering that possible interindividual variation, recently studies under optimal foraging theory have variation among individuals as a focus of interest. The species P. blainvillei is partionated in populations along its range and probably, subpopulations can be found in the Sao Paulo state coast: northern, central and southern. Hence, my first goal was to investigate if there is diet variation among the three franciscana subpopulations from Sao Paulo coast. Additionally, I searched for which factors would be the diet structure defined within one of the subpopulations (the central one). I have considered the seasonality, individual gender and sex as possible factors influencing the diet structure within the central subpopulation. I had 58 franciscana specimens obtained from bycatch in the Sao Paulo coast, being them from northern, central and southern regions. They were juveniles and adults of both genders and bycaught in all the seasons. I identified the prey species from the gut contents with fish otholits and squid beaks. I estimated prey length and weight using regressions with that structures measures and I investigated the diet structure using a diet variation index. Within the central subpopulation I found no diet variation based on seasonality or individual gender, instead I found diet variation for individuals from different ages. Probably, most of the diet variation among subpopulations is due to prey availability spatial difference. The lack of diet variation based on seasonality may be due to little seasonal variation in the abundance of the main prey, P. harroweri. The lack of variation due to gender is probably related to the prey selection on soft body and easy digestion instead of prey size, being this type of selection common for both genders. Juveniles franciscana preyed on more species than the adults and that niche shift as an age effect can be consequence of forraging skills development. Enclosing, even discarding the effects of the spacial and temporal prey availability, individual gender and age, I found interindividual-level diet variation within the central subpopulation, which can points out to franciscana individual specialization, but isotopic studies are required to infer that specialization
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Příprava přírodních doplňků stravy s obsahem probiotických bakterií a látek s protizánětlivým účinkem / Preparation of food supplement containing probiotic bacteria and components with anti-inflammatory effectHorňáková, Nikola January 2020 (has links)
The presented thesis discusses the issues of chronic inflammatory diseases of the digestive system and suggests the possibility of the alternative natural remedies improving the health conditions or prolonging the remission phase of IBD. The main goal is to design a probiotic supplement enriched by natural anti-inflammatory agents. Phytochemicals, concretely phenolic compounds, flavonoids, and carotenoids suppress harmful inflammatory processes by direct targeting the function of the immune cells or by inhibiting damaging oxidative stress in general. Therefore, there were several plants potentially rich for these biologically active substances selected. Concretely, blueberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), turmeric (Curcuma longa), peppermint (Mentha piperita), chamomile (Matricaria recutita), cinnamon (Cinnamomum zeylanicum), ginger (Zingiber officinale) and flax (Linum usitatissimum). The suitable parts of these plants were extracted by using a total of three different solvents – water, ethanol, and hexane for obtaining lipidic extracts. The concentration of total polyphenols, total flavonoids, total carotenoids, and the ascertainment of specific polyphenols was determined in the prepared extracts. These characteristics were enhanced by the measurement of antioxidant activity of the aqueous and ethanolic extracts. The interaction of individual samples with probiotic cultures (Bifidobacterium breve, Lactobacillus acidophilus) and the ability of extracts to influence the viability of probiotics in the model digestion process has been examined. The most interesting samples (aqueous extracts of blueberries, mint, chamomile, and cinnamon) were selected for further experiments. The possible cytotoxicity towards human intestinal epithelial cells was tested in vitro by the MTT tests utilizing the CaCo-2 cell line. Extracts showing the highest levels of beneficial phytochemicals and antioxidant activity, supporting the growth of probiotic cultures, and showing minimal cytotoxic effects on human intestinal cells were then co-encapsulated with probiotics into alginate particles of a diameter of 1 mm. Water extracts of mint, chamomile, and cinnamon have been chosen. The encapsulation efficiency of successfully entrapped probiotics and phenolic compounds was determined in prepared particles. Furthermore, the particles were studied during the process of model digestion, when the release of the desired substances in the various parts of the digestive system was observed and assessed whether the components would reach the crucial point of action – the colon. For the use of the proposed probiotic mixture as a dietary supplement, a recommended dose of 1 g has been determined. Lastly, possible adjustments such as lyophilization or sheathing by an extra protective polymerous layer, e.g. chitosan, were suggested to prolong the shelf life of the particles and volatile substances stability.
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OMICS APPROACH TO INVESTIGATE THE ROLE OF ENTERIC BACTERIA IN METABOLIZING FOOD COMPONENTSSENIZZA, ALICE 08 April 2020 (has links)
In questa tesi di Dottorato, l’obiettivo era valutare l’impatto di diversi ingredienti alimentari sul metabolismo di alcuni batteri intestinali e viceversa, mediante l’applicazione di tecniche omiche. Utilizzando le tecniche di metabolomica e trascrittomica, è stata studiata la risposta all’acido linoleico del ceppo Bifidobacterium breve DSM 20213. Utilizzando un approccio combinato di metagenomica e metabolomica, è stato possibile studiare le modifiche a carico del microbiota intestinale, del profilo fenolico e degli acidi grassi, in biscotti senza glutine (a base di erba medica) durante digestione e fermentazione in vitro. Inoltre, è stato valutato come alcuni batteri potessero interferire negativamente su una terapia farmacologica a base di Diclofenac, un farmaco usato per alcune patologie intestinali. Per questo tipo di studio è stata utilizzata la spettrometria di massa ad alta risoluzione, che ha consentito di ipotizzare un coinvolgimento dell’enzima batterico β-glucuronidasi.
Una sola tecnica omica, seppure di ultima generazione, non permette di valutare tutte le modificazioni del microbiota intestinale data la complessità dei fattori coinvolti. Per questa ragione, integrare più approcci omici potrebbe risultare una buona strategia per analizzare il reale impatto del microbiota sulla salute dell’ospite. Questo permetterebbe di valutare le interazioni microbiota-ospite, i principali metabolismi e le interconnessioni tra gruppi batterici coinvolti nella risposta ad uno stimolo esterno come l’assunzione di particolari ingredienti con l’alimentazione. / The aim of the present PhD thesis was to explore the metabolic response of intestinal bacteria to food components by using ‘omics’ approaches. In particular, the first part of this thesis was focused on the effect of linoleic acid on Bifidobacterium breve DSM 20213 strain. Firstly, an untargeted metabolomics-based approach was used to explore the primary changes in metabolic profile of this strain grown in presence of linoleic acid. Secondly, the gene expression of B. breve DSM 20213 induced by linoleic acid exposure was investigated. Integrated use of metabolomics/transcriptomics was applied to better understand the response mechanisms to linoleic acid stress. In the third part of the thesis, using a combination of metagenomics and metabolomics, the in vitro large intestine fermentation of gluten-free rice cookies containing alfalfa seed was investigated. In the last part of my PhD, the negative effect of β-glucuronidase producing bacteria was evaluated by means of qualitative high-resolution mass spectrometry.
Based on my experience there is not a gold standard approach for evaluating a complex environment such as the gastrointestinal tract. For this reason, an integrated use of different techniques should be mandatory to have an accurate framework of gut microbiota composition, its potential metabolic network and the impact on the host physiology and health.
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The nematode-based food-chain of a temperate deciduous forestHeidemann, Kerstin 07 March 2013 (has links)
No description available.
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Bodenverbesserungsmittel auf heterogenen StandortenPößneck, Jörg 16 June 2016 (has links)
Die Broschüre informiert zum Einsatz von Bodenverbesserungsmitteln und deren Kombination mit Kompost. Kompost mit Additiv hat ein höheres Wasserhaltevermögen und einen höheren Sauerstoffgehalt. Kompost in Kombination mit einem geeigneten Bodenverbesserungsmittel unterstützt die Kulturpflanzen bei der Überbrückung von Vorsommertrockenperioden. Mit der teilschlagbezogenen Kompostausbringung können die bodenbedingt schwachen Teilflächen ertragsseitig stabilisiert und gefördert werden. Landwirtschaftsbetriebe haben mit Kompost aus Eigenproduktion eine pflanzenbaulich nachhaltig wirkende Option.
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Zánětem vyvolané změny v expresi kanabinoidních receptorů v ptačím mozku / Inflammation-associated changes in cannabinoid receptor expression in avian brainDivín, Daniel January 2020 (has links)
(EN) Research in interactions between the nervous and immune systems is focused mainly on mammals, while in other vertebrates, including birds, it remains neglected. Two types of cannabinoid receptors interconnect the nervous and immune systems: CB1, which is in mammals involved in regulation of neural processes, and CB2, which is in mammals involved in regulation of immune processes. However, little is presently known about the roles of these receptors in nervous and especially immune processes in birds. Therefore, in this work I focus on the expression of cannabinoid receptors in cognitively advanced bird species (parrots, passerines) during induced sterile peritoneal inflammation. Unlike passerines, parrots appear to lack the gene for CB2, which may affect the inflammation regulation. I have revealed no changes in the expression of these receptors during peritoneal inflammation neither in parrots, nor in songbirds. Nevertheless, the increase in expression of the proinflammatory cytokine IL- 1β in the brain in parrots confirms the importance of neuroimmune interaction and mutual influences along the gut-brain axis. This work suggests that even in birds, the central nervous system is affected by inflammation through the gut-brain axis. The expression of cannabinoid receptors does not change much...
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Health consequences of group living in wild Verreaux’s sifakas (Propithecus verreauxi)Rudolph, Katja 07 February 2020 (has links)
No description available.
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