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Artykuły w czasopismach na temat "Acides gras 3-hydroxylés (3-AGH)"
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Guy-Grand, Bernard. "Acides gras oméga 3 : aspects métaboliques". Oléagineux, Corps gras, Lipides 11, nr 1 (styczeń 2004): 29. http://dx.doi.org/10.1051/ocl.2004.0029.
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Denis, I., C. Heberden, S. Vancassel i M. Lavialle. "Acides gras polyinsaturés n-3 (oméga 3) et cerveau". Médecine & Nutrition 47, nr 2 (2011): 17–28. http://dx.doi.org/10.1051/mnut/201120004.
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Bourre, Jean-Marie. "Acides gras oméga-3 alimentaires et neuropsychiatrie". Oléagineux, Corps gras, Lipides 11, nr 4-5 (lipiec 2004): 362–70. http://dx.doi.org/10.1051/ocl.2004.0362.
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Dallongeville, Jean, Nadine Marecaux i Philippe Amouyel. "Acides gras oméga-3 et risque cardiovasculaire". Oléagineux, Corps gras, Lipides 17, nr 4 (lipiec 2010): 232–35. http://dx.doi.org/10.1051/ocl.2010.0317.
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Dallongeville, J. "Acides gras oméga-3 et risque cardiovasculaire". Médecine des Maladies Métaboliques 3, nr 5 (listopad 2009): 491–95. http://dx.doi.org/10.1016/s1957-2557(09)73296-1.
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Guesnet, Philippe, Jean-Marc Alessandri, Sylvie Vancassel, Isabelle Denis i Monique Lavialle. "Acides gras oméga 3 et fonctions cérébrales". Nutrition Clinique et Métabolisme 19, nr 3 (wrzesień 2005): 131–34. http://dx.doi.org/10.1016/j.nupar.2005.06.004.
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Bourre, Jean-Marie. "Acides gras ω-3 et troubles psychiatriques". médecine/sciences 21, nr 2 (luty 2005): 216–21. http://dx.doi.org/10.1051/medsci/2005212216.
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Guy-Grand, Bernard. "Les acides gras oméga-3 au pilori ?" Cahiers de Nutrition et de Diététique 47, nr 5 (listopad 2012): 213–14. http://dx.doi.org/10.1016/j.cnd.2012.10.003.
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Laurent-Jaccard, Anne. "Place des acides gras oméga 3 dans l’alimentation". Revue Médicale Suisse 2, nr 59 (2006): 839–42. http://dx.doi.org/10.53738/revmed.2006.2.59.0839.
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Chalon, Sylvie. "Acides gras polyinsaturés n-3, neurotransmission et fonctions cognitives". Oléagineux, Corps gras, Lipides 7, nr 1 (styczeń 2000): 68–73. http://dx.doi.org/10.1051/ocl.2000.0068.
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Véquaud, Pierre. "Développement et application de nouveaux marqueurs d’environnement d’origine bactérienne en milieu terrestre". Electronic Thesis or Diss., Sorbonne université, 2021. http://www.theses.fr/2021SORUS475.
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A ce jour, les seuls biomarqueurs organiques utilisables pour la reconstruction de la température et du pH en milieu terrestre sont les alkyl tetraéthers de glycérol bactériens (GDGTs ramifiés ou brGDGTs). Ce travail de thèse s’est intéressé au développement et à l’application d’autres marqueurs bactériens, les acides gras 3-hydroxylés (3-AGH). L’analyse de l’abondance des 3-AGHs et des brGDGTs dans 49 sols prélevés dans les Alpes françaises a permis de quantifier l'influence de paramètres environnementaux autres que la température sur la distribution des brGDGTs et des 3-AGHs. En parallèle, des expériences de microcosmes menées sur 4 de ces sols pendant 1 an à différentes températures n’ont pas permis d’observer une évolution des abondances relatives de 3-AGHs mais une augmentation de la proportion de certains brGDGTs. Une première calibration globale des 3-AGHs comme marqueurs de température et de pH a été proposée à partir de 168 échantillons de sols provenant du monde entier. Ce travail a démontré l’intérêt de nouvelles approches utilisant l’apprentissage automatisé pour établir des calibrations de marqueurs. Enfin une calibration globale améliorée des brGDGTs comme marqueurs de température et de pH en milieu terrestre a été proposée (modèle FROG). Ces différentes calibrations ont été appliquées sur des archives paléoclimatiques. L’ensemble des connaissances acquises ont permis d’affiner la compréhension de l’influence de différentes variables environnementales sur la distribution des lipides membranaires utilisés comme marqueurs d’environnements en milieu terrestre, et de proposer de nouvelles approches statistiques pour établir des calibrations de marqueursTo date, the only biomarkers that can be used for temperature and pH reconstruction in terrestrial environments are bacterial glycerol dialkyl glycerol tetraethers (branched GDGTs or brGDGTs). This PhD work focused on the development and application of other proxies of bacterial origin, 3-hydroxy fatty acids (3-OH FAs). The analysis of the abundance of 3-OH FAs and brGDGTs in 49 soils sampled in the French Alps made it possible to quantify the influence of environmental parameters other than temperature on the distribution of brGDGTs and 3-OH FAs. In parallel, microcosm experiments carried out on 4 of these soils for 1 year at different temperatures did not reveal any change in the relative abundances of 3-OH FAs but an increase in the proportion of certain brGDGTs. A first global calibration of 3-OH FAs as temperature and pH proxies was proposed from 168 soil samples globally distributed. This work demonstrated the interest of new approaches using machine learning to establish biomarker calibrations. Finally, an improved global calibration of brGDGTs as temperature and pH proxies in terrestrial environments was proposed (FROG model). These different calibrations were successfully applied and validated on paleoclimatic archives. This work enabled to refine the understanding of the influence of different environmental variables on the distribution of membrane lipids (3-OH FAs and brGDGTs) used as environmental proxies in terrestrial environments, and to propose new statistical approaches to establish environmental proxies calibrations
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Pineda, Catherine. "Les acides gras Oméga 3 polyinsaturés : ont-ils un rôle antiathérogène ?" Bordeaux 2, 1993. http://www.theses.fr/1993BOR2PE71.
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Sehl, Anthony. "Impact de la forme moléculaire et supramoléculaire de vectorisation des acides gras polyinsaturés n-3 sur leur biodisponibilité : étude physico-chimique et in vivo chez le rat". Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0065.
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Les dernières données de consommation alimentaire de la population française démontrent que les apports nutritionnels en acide eicosapentaénoïque (EPA) et en acide docosahexaénoïque (DHA) sont nettement inférieurs aux recommandations fixées par l’Agence nationale de sécurité sanitaire, de l’alimentation, de l’environnement et du travail (ANSES). Compte tenu de leurs rôles physiologiques, l’amélioration de leur biodisponibilité est devenue une priorité nutritionnelle. La maitrise des formes de vectorisation des acides gras polyinsaturés à longue chaine de la série n-3 (AGPI-LC n-3) représente une piste d’intérêt afin de répondre à cette problématique. C’est dans ce contexte que s’inscrit ce travail de thèse, visant à étudier l’influence de la forme moléculaire (phospholipides (PL) vs triglycérides (TG)) et/ou supramoléculaire (phase continue, émulsion, liposomes) de vectorisation des AGPI-LC n-3 sur leur devenir métabolique.La démarche expérimentale adoptée a consisté, dans un premier temps, à caractériser les différentes formes de vectorisation des AGPI-LC n-3 par un couplage de méthodes d’analyse physico-chimiques (microscopie optique, granulométrie, mesure des produits primaires et secondaires d’oxydation, lipolyse enzymatique). Les données obtenues ont permis de poser des hypothèses mécanistiques pour l’étude de la biodisponibilité chez le rat. Ainsi, dans un deuxième temps, l’étude in vivo a permis d’aborder (1) l’absorption intestinale des acides gras (AG) suite à un apport en bolus de lipides et (2) l’accrétion tissulaire suite à un régime de 8 semaines.Les résultats indiquent que la forme moléculaire de vectorisation des AGPI-LC n-3 (TG marins vs PL marins, en phase continue) n’influence pas leur absorption intestinale mais plutôt leur incorporation dans les lipides lymphatiques, principaux transporteurs des AG alimentaires dans l’organisme. A l’inverse, la structuration des PL marins en milieu aqueux (émulsion ou liposomes), permet d’améliorer l’absorption de l’EPA et du DHA, de façon spécifique à la nature de la structuration supramoléculaire. Les résultats de l’accrétion tissulaire montrent qu’au terme des 8 semaines de régime, l’enrichissement tissulaire en AGPI-LC n-3 s’effectue de façon différente selon leur forme moléculaire de vectorisation. Ainsi, la consommation de TG marins favorise l’incorporation des AGPI-LC n-3 dans les lipides hépatiques, alors que la supplémentation des régimes en PL marins permet d’orienter le DHA vers le cerveau et la rétine.L’ensemble de ces résultats montre que le choix de la forme moléculaire de vectorisation des AGPI-LC n-3 (PL vs TG) peut être un moyen d'orienter leur incorporation tissulaire, alors que leur structuration supramoléculaire (émulsion ou liposomes), une stratégie pour moduler leur absorption intestinaleThe latest data from the cross-sectional national French dietary study show that dietary intakes of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are significantly lower than those recommended by the French Agency for Food, Environmental and Occupational Health & Safety (ANSES). Considering their physiological roles, improving their dietary intake has became a nutritional priority. The control of the different forms of n-3 long chain polyunsaturated fatty (n-3 LC-PUFA) intake represents an interesting way to address this issue. In this context, this thesis aims at studying the influence of the molecular form (phospholipids (PL) vs triglycerides (TG)) and/or supramolecular form (continuous phase, emulsion, liposomes) of n-3 LC-PUFA towards their bioavailability.The experimental approach consisted in characterizing the different forms of n-3 LC-PUFAs by coupling various physicochemical methods (optical microscopy, granulometry, measurement of primary and secondary oxidation products, enzymatic lipolysis). The data obtained made it possible to propose some mechanistic hypothesis for the bioavailability studies conducted in rat. Thus, in a second step, the in vivo study made addresses (1) the intestinal absorption of fatty acids following a single dose of lipids and (2) the lipid tissue accretion following an 8-week diet.The data obtained from the intestinal absorption study indicate that the molecular form of n-3 LC-PUFA targeting (marine TG vs marine PL, in continuous phase) does not influence their intestinal absorption but rather their incorporation into lymphatic lipids, which are the main carriers for dietary fatty acids in the organism. Conversely, structuring marine PL (emulsion or liposomes) improves the EPA and DHA absorption, but differently according to the supramolecular form. The results concerning tissue accretion show that, after 8-week diet, the tissue enrichment in n-3 LC-PUFA is different according to the molecular form of targeting. The consumption of marine TG favours the incorporation of n-3 LC-PUFA into hepatic lipids, while the supplementation of diets with marine PL targets DHA preferentially to brain and retina.All these results show that the molecular form of targeting (PL vs TG) of n-3 LC-PUFA can be a way for managing their tissue incorporation, whereas the supramolecular organization (emulsion or liposomes) can be envisaged to monitor their intestinal absorption
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Mies, Frédérique. "Régulation du canal sodium épithélial par les acides gras polyinsaturés n-3". Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210514.
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I. DESCRIPTION DE PROJET DE RECHERCHELe canal sodium épithélial bloquable par l’amiloride (ENaC) est une protéine intégrale de la membrane apicale des épithéliums impliqués dans l’absorption du sodium. Deux fonctions majeures sont directement liées au fonctionnement d’ENaC. D’une part, la régulation de la balance sodée par le rein et donc de la pression artérielle et d’autre part, la clairance du fluide alvéolaire pulmonaire.
Le transport vectoriel de sel et d’eau à travers ces épithéliums à jonctions serrées repose sur un transport actif de sodium entraînant un flux osmotique d’eau. Ce transport de sodium s’effectue en deux étapes: l’entrée apicale, par diffusion, facilitée via ENaC, et la sortie basolatérale, active, par les pompes Na+/K+ ATPases.
Ces dernières années, un intérêt grandissant est porté sur les acides gras polyinsaturés à longues chaînes de type oméga 3 (PUFAs) et leurs implications dans divers processus physiologiques. Entre autres effets, les PUFAs modulent différents types de canaux ioniques (canaux Na+ dépendant du voltage, Ca++ L-type, K+).
Les études in vivo impliquant un effet à long terme des PUFAs décrivent des mécanismes inhibiteurs. Cependant, lors d’une étude précédente, axée sur la composition lipidique des membranes de cellules rénales en culture et l’influence de l’ajout d’acides gras saturés et insaturés sur le transport du sodium, nous avons constaté que les acides gras polyinsaturés à longues chaînes de type oméga 3 augmentaient la réabsorption du sodium. Ces résultats pourraient être intéressants, car les canaux sodiques de l’épithélium alvéolaire sont en contact direct avec le surfactant, dont la composition lipidique varie en fonction de l’apport alimentaire en PUFAs. Chez les prématurés humains, le syndrome de détresse respiratoire est une des causes les plus fréquentes de mortalité. Dans un certain nombre de cas, on peut restaurer une fonction pulmonaire satisfaisante par l’administration de surfactant.
Dans ce travail, nous avons opté pour une approche fondamentale des mécanismes de régulation du canal sodium épithélial par l’acide eicosapentanoïque (EPA, C 20:5, n-3). Des études électrophysiologiques, biochimiques et d’imagerie cellulaire ont été réalisées sur la lignée cellulaire A6 de rein d’amphibien, qui sert d’épithélium modèle pour l’étude d’ENaC depuis plus de 25 ans. Cette lignée exprime des canaux sodiques très sélectifs et possède des propriétés électrophysiologiques facilitant l’étude de leur régulation.
Ce travail nous a permis de mettre en évidence de nouveaux mécanismes fondamentaux dont la pertinence physiologique et /ou clinique ne pourra être établie qu’en transposant cette étude sur un modèle in vivo, comme nous le proposons dans les perspectives.
Dans le présent travail, nous avons étudié :
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Doctorat en Sciences biomédicales et pharmaceutiques
info:eu-repo/semantics/nonPublished
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Ghandour, Rayane. "Effet des acides gras polyinsaturés sur la conversion des adipocytes blancs en adipocytes brites". Thesis, Nice, 2016. http://www.theses.fr/2016NICE4010/document.
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Il existe deux populations d’adipocytes thermogéniques, les adipocytes bruns du tissu adipeux bruns et les adipocytes ‘’brites’’ qui apparaissent au sein du tissu adipeux blanc. Récemment, la caractérisation d’adipocytes bruns et brites fonctionnels chez l’homme adulte a permis d’envisager de nouvelles approches nutritionnelles et thérapeutiques pour traiter l’obésité. Mon projet de thèse a porté sur l’étude des effets des acides gras polyinsaturés ω6 et ω3 d’origine alimentaire sur la conversion des adipocytes blancs en brites, d’abord chez l’homme in vitro puis chez les rongeurs in vivo. Nous avons pu ainsi démontrer que l'acide arachidonique ω6 à l’origine de nombreux métabolites oxygénés, exerce 1) un effet inhibiteur sur la formation des adipocytes brites grâce aux prostaglandines E2 et F2α, et 2) un effet inducteur via la prostacycline. En effet, celle-ci active la conversion des adipocytes blancs en brites par une voie impliquant le récepteur membranaire IP et les récepteurs nucléaires PPARs. En nous basant sur les recommandations nutritionnelles actuelles chez l’Homme, qui ont pris en considération l’insuffisance de l’apport en acides garsω3 par rapport à l’excès des ω6, nous avons pu montrer chez la souris qu’une supplémentation en acides gras ω3 dans le régime alimentaire était capable d’inhiber l’effet néfaste des acides gras ω6 et d’activer le tissu adipeux brun. Nos résultats démontrent l’importance de la biodisponibilité de l’acide arachidonique dans la biologie du tissu adipeux et permettent de renforcer l’idée que le rééquilibrage du ratio ω6/ω3 est un outil de choix dans la prévention du surpoids et de l’obésité et les maladies métaboliques associéesThere are two types of thermogenic adipocytes able to use fatty acids and glucose to produce heat. We distinguish brown adipocytes from the brown adipose tissue and ‘’brite’’ adipocytes which occur into the white adipose tissue. Recently, the characterization of functional brown and brite adipocytes in adult humans has led to the consideration of their use to treat obesity by increasing energy expenditure. My thesis project was to study the effect of dietary polyunsaturated fatty acids, on the conversion of white into brite adipocytes, in vitro and in vivo, in humans and rodents respectively. We demonstrated that arachidonic acid ω6, precursor of prostaglandins, has 1) an inhibitory effect on the recruitment of brite adipocytes via prostaglandins E2 and F2α and 2) an activatory effect via prostacyclin. In fact, prostacyclin induces the conversion of white into brite adipocytes through the IP receptor and the PPARs signaling pathways. Based on human present nutritional recommendations, we demonstrated that a supplementation of ω3 fatty acids in mice diet was able to inhibit the negative effect of ω6 fatty acids and activate brown adipose tissue. Our data highlights the importance of arachidonic acid bioavailability on the biology of adipose tissue and reinforce the idea that an equilibrate ω6/ω3 ratio is a tool that can be used to prevent overweight obesity and associated metabolic disorders
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Correia, Maria Marta de Ascensao Teixeira. "Rôle des acides gras polyinsaturés n-3 sur la régulation de l’inflammation et le processus de tumorigenèse déclenché par Helicobacter pylori". Thesis, Paris 11, 2012. http://www.theses.fr/2012PA114846.
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La bactérie Helicobacter pylori est responsable de l’infection la plus répandue dans la population mondiale. Cette bactérie est considérée comme le principal agent étiologique de la gastrite chronique, de l’ulcère duodénal et du cancer gastrique non-héréditaire. La thérapeutique prescrite pour l’éradication de cette infection est inefficace pour un nombre de plus en plus élevé de patients, dû à l’induction constante de souches résistantes aux antibiotiques habituellement prescrits.H. pylori a aussi d’autres façons d’assurer sa survie dans le milieu gastrique que l’induction de résistances aux antibiotiques. En particulier en intéragissant avec le cholestérol des cellules épithéliales gastriques. De ce fait, l’utilisation de molécules inhibitrices de la croissance de H. pylori, autres que les antibiotiques classiques, est une stratégie importante pour combattre cette infection.L’objectif majeur de ce travail a été de mettre en évidence de nouvelles molécules inhibitrices de la croissance et de la viabilité de H. pylori, permettant ainsi le développement de solutions alternatives à la thérapeutique classiquement utilisée. Les acides gras polyinsaturés et l’acide docosahexaenoic (DHA) se mettre en lumière pour réunir incontestable propriété anti-inflammatoires et anti-tumoral. Nous avons émis l’hypothèse que le DHA influence la survie de H. pylori, et peut moduler la disponibilité des acides gras et du cholestérol cellulaires.Nos résultats montrent que le DHA inhibe la croissance de H. pylori in vitro et affecte sa capacité à coloniser la muqueuse gastrique dans le modèle souris. Dans ces conditions, le DHA diminue la réponse inflammatoire gastrique induite par l’infection. Au niveau des cellules épithéliales gastriques, des modifications du profil des acides gras et du cholestérol avec des conséquences sur le métabolisme et la signalisation cellulaire sont observées. De plus, un traitement antibiotique classique combiné à une administration de DHA aux souris infectées diminue de façon drastique la récidive de l’infection. En conclusion, cette étude démontre un effet inhibiteur du DHA sur l’infection par H. pylori et sa récidive. Ces résultats justifient la proposition du DHA comme coadjuvant thérapeutique, constituant ainsi une stratégie prophylactique alternative de l’éradication de l’infection par H. pyloriH. pylori infection is extremely common worldwide and is recognized as a major etiological factor in chronic active gastritis, gastric duodenal ulcers and gastric cancer development. H. pylori eradication treatment has not changed to a large extent in the last decades and can raise some concern mainly due to recurrence of infection, and most importantly, acquired resistance to classically used antibiotics. In this context, the use of compounds other than antibiotics that could decrease H. pylori infection in a safe way could provide an alternative to tackle this problem. It is known that H. pylori extracts cholesterol from host cell-membrane rafts, modifies it into an α-glycosylated form, and uses this mechanism to increase its survival. The main aim of this thesis work was to explore the role of different non-antibiotic molecules in inhibiting H. pylori growth. Among molecules known to affect in vitro H. pylori growth and viability are certain polyunsaturated fatty acids (PUFAs). Within the many molecules available, we concentrated our efforts on the study of docosahexaenoic acid (DHA). We also pursued the hypothesis that DHA affects survival of H. pylori by modulating the host epithelial cell levels of fatty acids and cholesterol availability.Our results show that DHA inhibits H. pylori growth both in vitro and in vivo, and attenuates the host inflammatory response. Additionally, we demonstrate that DHA induces morphological and cell wall protein composition changes that altogether decrease bacteria-gastric epithelial cell adherence, inflammation and survival. Also, we demonstrated that DHA alters cholesterol levels in epithelial cells, thereby influencing H. pylori ability to uptake and use epithelial cholesterol. This will ultimately impair H. pylori survival. Importantly, the combination of DHA and antibiotic standard treatment decreased the recurrence of H. pylori infection in a mouse model. Our results have gathered important evidence to pave the way for DHA use in the clinical setting and in prophylactic/preventive strategies against H. pylori infection
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Plé, Aude Marie-Laure. "Effet de l'acide docosahexaenoïque (DHA), un acide gras polyinsaturé de la famille n-3, dans l'activation des cellules T". Dijon, 2008. http://www.theses.fr/2008DIJOS057.
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Nous avons étudié le rôle de l’acide docosahexaenoïque (DHA) dans la régulation de la signalisation calcique, la voie des Src Tyrosines kinases et l’activation des canaux TRPC3/6, des étapes clés contrôlant la prolifération cellulaire. De plus, dans les lymphocytes T régulateur murin, nous avons remarqué que le DHA, via son action inhibitrice sur IL-10 induit in vivo et in vitro une inhibition de la prolifération cellulaire. L’analyse des chemokines montre que le DHA exerce un effet sur la migration et l’adhésion des cellules T régulatrices en régulant l’expression des protéines ERK1/2 et Akt. Le DHA, module les fonctions cellulaires en agissant directement sous forme d’acide gras libre, ou bien, indirectement sous forme estérifiée en position sn-2, dans les diacylglycérols (DAG). Classiquement, l’influx calcique est déclenché suite à la déplétion des réserves calciques intracellulaires, selon un mécanisme dit store-operated Ca2+ (SOC) entry (SOCE), via l’ouverture de canaux dits SOC, qui peuvent être les canaux CRAC (Ca2+ release-activated Ca2+ channels) ou les canaux TRPC (Canonical Transient Receptor Potential). Parmi les canaux TRPC, ce sont les canaux TRPC3/6/7 qui sont régulés par les DAG. Dans les cellules Jurkat, seul TRPC3 et TRPC6 sont présents et exprimées différemment en fonction du stade de prolifération et cycle cellulaire. Dans les cellules monocytaires U937, nous avons montré que le DHA, augmente le [Ca2+]i via l’ouverture des canaux CRAC et l’activation des PKC. . . D’un point de vue physiologique, nous avons démontré que la signalisation calcique déclenchée en amont par le DHA déclenche l’apoptose, évaluée par la production de radicaux libres oxygénés (RLO) et l’activation de la caspase-3. L’ensemble de ces résultats permet de soutenir l’hypothèse selon laquelle, le DHA exerce des effets immunomodulateurs, en partie, via l’augmentation de la [Ca2+]i, et l’inhibition de la voie de signalisation PKC/MAPKIn this study, we investigated the role of docosahexaenoic acid, an n-3 PUFA, in the regulation of calcium, Src tyrosine kinase signaling and activation of TRPC3/6 channels. Furthermore, in mouse T regulatory cells we have shown that DHA via an inhibition of IL-10 induces in vivo and in vitro an inhibition of cell proliferation. The analysis of chemokines shows that DHA exert an effect on T reg migration and adhesion by regulating the expression of ERK1/2 and Akt protein. DHA modulates cell functions directly in the form of free fatty acid or, indirectly in etherified form at the sn-2 position in diacylglycerol (DAG). Classically, calcium influx is achieved following intracellular calcium stores depletion, through a mechanism termed as store-operated Ca2+ (SOC) entry (SOCE), via the opening of SOC channels that can be CRAC (Ca2+ release-activated Ca2+ channels) channels or TRPC (Canonical Transient Receptor Potential) channels. Among TRPC channels, TRPC3/6/7 channels are those which are regulated by DAG. In Jurkat T cells, only TRPC3 and TRPC6 were present and express differentially in relation to cell cycle and proliferation. In U937 cells, DHA induced increases in [Ca2+]i via the opening of CRAC channels and activation of PKC. . . By a physiological point of view, we have demonstrated that DHA-induced Ca2+ signaling can initiate apoptosis pathway, as assessed by the measurement of reactive oxygen species (ROS) production and caspase-3 activation. Together, these observations suggest that DHA exert immunomodulatory effects in part, by decreasing pHi, increasing [Ca2+]i and inhibiting PKC/MAP kinase pathway. Ngl
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FISCHER, MARIE-CHRISTINE. "Les proprietes nutritionnelles de la lignee lipidique n-3 en pathologie cardio-vasculaire". Strasbourg 1, 1989. http://www.theses.fr/1989STR15065.
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Drouin, Gaëtan. "Métabolisme et intérêt nutritionnel de l’acide docosapentaénoïque n-3 : modulation du statut tissulaire en acides gras n-3 par les lipides laitiers alimentaires chez le rat". Thesis, Rennes 1, 2018. http://www.theses.fr/2018REN1B020/document.
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L’optimisation du statut tissulaire en acides gras polyinsaturés à longues chaines n-3 (AGPILC n-3) fait partie des objectifs actuels en nutrition humaine. En effet, de nombreux effets bénéfiques sur la santé humaine ont été démontrés pour ces différents AGPILC n-3. Néanmoins, la bioconversion de ces dérivés à partir de leur précurseur alimentaire, l’acide α-linolénique, est limitée chez l’Homme et ne permet pas de subvenir aux besoins. Parmi cette famille d’acides, l’acide docosahexaénoïque (DHA) et de l’acide eicosapentaénoïque (EPA) ont été largement étudiés à l’inverse de ceux de l’acide docosapentaénoïque n-3 (DPA). Le premier objectif de ces travaux a été d’étudier l’impact d’une supplémentation nutritionnelle en DPA sur le métabolisme des acides gras et le métabolisme lipidique chez le rat sain. Pour cela, une méthode de purification du DPA à haute pureté et en grande quantité par chromatographie liquide a tout d’abord été mise en place. Ce résultat participe à faciliter la recherche future des effets in vivo du DPA dont la disponibilité commerciale est faible. Après sa supplémentation nutritionnelle, le DPA a été incorporé dans de multiples tissus et a impacté les compositions tissulaires en AGPILC n-3 de certains organes spécifiques comme le foie, le cœur, le poumon, la rate et le rein. Ainsi, la supplémentation en DPA pourrait être une source d’EPA, de DPA, et dans une moindre mesure de DHA. Enfin, comparé à une supplémentation en EPA ou en DHA, le DPA a été l’AGPILC n-3 le plus puissant pour améliorer la triglycéridémie et la cholestérolémie des animaux. Ces informations participeront certainement à une prise en compte plus importante du DPA tant dans les études nutritionnelles ainsi que dans l’installation des futures recommandations nutritionnelles. Le deuxième axe de recherche a porté sur la capacité d’une incorporation partielle de lipides laitiers dans le régime à augmenter le statut tissulaire en AGPI-LC n-3. L’incorporation de lipides laitiers a augmenté le statut en DHA cérébral et rétinien et le statut en DPA dans les autres tissus étudiés. De plus, l’induction de la conversion des AGPILC n-3 à partir de leur précurseur par les lipides laitiers a été complémentaire avec la supplémentation en DPA pour augmenter le statut tissulaire en AGPI-LC n-3. Ces résultats s’insèrent dans un contexte de nutrition infantile, période pendant laquelle l’incorporation des AGPI-LC n-3 est maximale dans les tissus nerveux. Ainsi, ces résultats apportent des données intéressantes tant pour les entreprises que pour les professionnels de santé pour recommander à la consommation des formules infantiles contenant des lipides laitiersThe optimization of tissue status in n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) is one of the current goals in human nutrition. Indeed, many beneficial effects on human health have been demonstrated for these different n-3 LCPUFA. However, the bioconversion of these derivatives from their food precursor, α-linolenic acid, is limited in humans and it does not meet the needs of the organism. Among this family of fatty acids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have been widely studied in contrast to those of n-3 docosapentaenoic acid (DPA). The first objective of this work was to study the impact of dietary supplementation with DPA on fatty acid metabolism and lipid metabolism in healthy rats. For this, a method for purifying DPA with high purity and in large quantities by liquid chromatography was first established. This result helps future research of the in vivo effects of DPA, poorly commercially available. After its nutritional supplementation, DPA was incorporated into multiple tissues and it has affected the n-3 LCPUFA tissue compositions of specific organs such as the liver, heart, lung, spleen and the kidney. Thus, supplementation with DPA could be a source of EPA, DPA, and to a lesser extent DHA. Finally, compared to supplementation with EPA or DHA, DPA was the most potent n-3 LCPUFA to improve triglyceridemia and cholesterolemia in animals. This information will certainly contribute to a greater consideration of DPA both in nutritional studies and in the direction of future nutritional recommendations. The second area of research focused on the ability of a partial incorporation of dairy lipids in the diet to increase the tissue status in n-3 LCPUFA. Incorporation of dairy lipids in the diet increased DHA status in brain and retina and DPA status in the other studied tissues. In addition, the induction of conversion of n-3 LCPUFA from their precursor by dairy lipid was complementary with the DPA supplementation to increase n-3 LCPUFA status in tissues. These results fit into a context of infant nutrition, during which the incorporation of n-3 LCPUFA is maximal in nervous tissues. Thus, these results provide interesting data for both companies and health professionals to recommend infant formulas containing dairy lipids for consumption
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Pierre, Maud. "Effets des acides gras poly-insaturés oméga 3 et oméga 6 sur la fonction pulmonaire au cours d'une infection pulmonaire chronique à Pseudomonas aeruginosa chez la souris". Lille 2, 2007. http://www.theses.fr/2007LIL2S006.
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L'infection broncho-pulmonaire chronique à Pseudomonas aeruginosa est la cause principale de la morbidité et de la mortalité dans la mucoviscidose. Par une action anti-inflammatoire, les acides gras poly-insaturés (AGPI) de la série oméga 3 pourraient avoir un effet bénéfique sur la réaction inflammatoire bronchique. Le but de notre étude était d'évaluer les effets d'une alimentation riche en AGPI lors d'une infection pulmonaire chronique à P. Aeruginosa. Pour réaliser cette étude, des souris ont été nourries durant cinq semaines avec des diètes spécialement élaborées avec une haute teneur en acide gras oméga 3 (diète oméga 3) ou en acide arachidonique (diète oméga 6) en comparaison à une diète standard. Les souris ont ensuite été infectées par une injection intra-trachéale de billes d'agarose contenant P. Aeruginosa et les animaux ont été étudiés durant sept jours. Notre travail a permis dans un premier temps la validation d'un modèle chronique d'infection à P. Aeruginosa. Nous avons ensuite vérifié que la composition en acides gras des phospholipides membranaires des poumons et du foie était influencée par la composition en AGPI de la diète. Les souris nourries avec les AGPI oméga 3 présentent un meilleur taux de survie en comparaison aux souris nourries avec les deux autres diètes. Les différentes diètes n'influencent pas l'expression des gènes de virulence de P. Aeruginosa au cours de l'infection. Par contre au quatrième jour d'infection, les souris nourries avec les AGPI oméga 3 gagnent plus de masse maigre, présentent une diminution de l'expression des mucines pulmonaires Muc 5b et Muc 4 et ont une clairance liquidienne alvéolaire plus élevée en comparaison aux souris nourries avec les deux autres diètes. Après le premier jour d'infection, la concentration en TNF-a et en IL- 6 mesurée dans le liquide de lavage broncho-alvéolaire (LBA) des souris nourries avec les AGPI oméga 3 est plus basse en comparaison aux deux autres groupes. Les expressions des ARNm des a, b-ENaC et de l'a1Na+/K+-ATPase ne sont pas modulées par les différentes diètes. L'apport alimentaire en AGPI oméga 3 influence la composition en acides gras des phospholipides membranaires et est associées à une augmentation de la survie des souris lors d'une pneumonie chronique à P. Aeruginosa. Ce travail ouvre des perspectives sur l'utilisation des AGPI oméga 3 dans la prévention ou le contrôle de l'infection pulmonaire chronique à P. Aeruginosa chez les patients atteints de mucoviscidose.
Książki na temat "Acides gras 3-hydroxylés (3-AGH)"
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Oméga-3: Les meilleures recettes. Laval, Québec: G. Saint-Jean, 2007.
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Louise, Rivard. 200 recettes oméga-3. Montréal: Modus Vivendi, 2007.
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A, Drevon C., Baksaas I i Krokan Hans, red. Omega-3 fatty acids: Metabolism and biological effects. Basel: Birkhäuser Verlag, 1993.
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Gervais, Gérard. Les oméga-3 pour guérir: Prévention, soulagement, rémission des malaises et maladies de type chronique. Montréal: Guérin, 2004.
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1951-, Shahidi Fereidoon, i Finley John W. 1942-, red. Omega-3 fatty acids: Chemistry, nutrition, and health effects. Washington, D.C: American Chemical Society, 2001.
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Canada. Agriculture et agroalimentaire Canada. Enrichir la viande de porc en acides gras oméga-3. [Ottawa]: Agriculture et Agroalimentaire Canada, 2008.
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Laurence, Wittner, red. Les oméga 3 au menu: 150 recettes santé : leurs bienfaits santé, allergies, douleurs articulaires, troubles cardiaques, déprime, perte de poids. Paris: Le Grand livre du mois, 2004.
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Les huiles alimentaires: Choisir les meilleures. Paris: Éd. Médicis, 2006.
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Allport, Susan. The queen of fats: Why omega-3s were removed from the Western diet and what we can do to replace them. Berkeley: University of California Press, 2006.
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Allport, Susan. The queen of fats: Why omega-3s were removed from the Western diet and what we can do to replace them. Berkeley, CA: University of California Press, 2007.
Znajdź pełny tekst źródłaCzęści książek na temat "Acides gras 3-hydroxylés (3-AGH)"
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Díaz-Guerrero, Miguel Ángel, Meztlli O. Gaytán i Bertha González-Pedrajo. "Structure:Function of Transmembrane Appendages in Gram-Negative Bacteria". W Biogenesis of Fatty Acids, Lipids and Membranes, 1–19. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-43676-0_51-1.
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Schneewind, Olaf, i Dominique Missiakas. "Lipoteichoic Acid Synthesis and Function in Gram-Positive Bacteria". W Biogenesis of Fatty Acids, Lipids and Membranes, 163–80. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-50430-8_17.
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Díaz-Guerrero, Miguel Ángel, Meztlli O. Gaytán i Bertha González-Pedrajo. "Structure: Function of Transmembrane Appendages in Gram-Negative Bacteria". W Biogenesis of Fatty Acids, Lipids and Membranes, 671–89. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-50430-8_51.
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Schneewind, Olaf, i Dominique Missiakas. "Lipoteichoic Acid Synthesis and Function in Gram-Positive Bacteria". W Biogenesis of Fatty Acids, Lipids and Membranes, 1–18. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43676-0_17-1.
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Schneewind, Olaf, i Dominique Missiakas. "Lipoteichoic Acid Synthesis and Function in Gram-Positive Bacteria". W Biogenesis of Fatty Acids, Lipids and Membranes, 1–18. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-43676-0_17-2.
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Londonkar, Ramesh, i Maithilee Kesralikar. "In Vitro Anticancer Screening of Methanolic Extract of Stachytarpheta Mutabilis". W Proceedings of the Conference BioSangam 2022: Emerging Trends in Biotechnology (BIOSANGAM 2022), 188–204. Dordrecht: Atlantis Press International BV, 2022. http://dx.doi.org/10.2991/978-94-6463-020-6_19.
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AbstractIn therapeutic plants, phytochemicals are found in abundance. A family of verbena known as vervain (verbenaceae) consists of over 100 genera and nearly 2600 species. Among the Verbenaceae family is Stachytarpheta, a green perennial herb. The species is being examined in this study for its phytochemical, antioxidant, and anti-inflammatory properties. Stachytarpheta mutabilis methanol extracts were studied for their phytochemical screening, antimicrobial, anti-inflammatory, and anticancerous effects in the current study. Phytochemical study revealed the presence of alkaloids, flavonoids, glycosides, steroids, tannins, carbohydrates, and saponins, among other phytoconstituents. One fungus, Aspergillus niger, Staphylococcus aureus, and Bacillus subtilis, as well as four-gram (+) pathogens, including Staphylococcus aureus and Bacillus subtilis, and two gram (-) pathogens, including Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi, and Klebsiella pneumoniae, were disc diffusion tested for antibacterial activity. The nitric oxide scavenging assay was used to test for anti-inflammatory efficacy in vitro. DPPH, ABTS, and total antioxidant tests were used to evaluate antioxidant activity. Analyses such as TLC, GC-MS, and were performed as per common procedure. A nitric oxide scavenging experiment was utilised to determine the anti-inflammatory properties of the drug in vitro. Tests for antioxidant activity were conducted using DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)), and total antioxidant tests. MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) analysis has been used to do anticancer screening. Extracts from Stachytarpheta mutabilis were found to include flavonoids, tannins and phenolic compounds as well as terpenoids and steroids in their phytochemical analysis. Squalene, octadecanal, and butan-1-one were found in the GC-MS study as were thirty other bioactive chemicals such as 4-isopropylcinnamic acid and octadecanoic acid. The methanolic fractions of plant extracts were shown to be effective against all bacteria. Anti-inflammatory and antioxidant experiments performed in the lab revealed the compounds’ potent inhibition activity. Analysis of the GC-MS data revealed the existence of thirty distinct components. MTT assay on the extract revealed anticancer activity. The data shows that the methanolic extract has a significant properties. Stachytarpheta mutabilis has therapeutic value and other pharmaceutical qualities may be assessed as a result of these results, which support the traditional usage of folk medicine as well.
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Rautenberg, Maren, Thomas Kohler, Guoqing Xia, Emir Kulauzovic i Andreas Peschel. "Structure, Biosynthesis, and Function of Teichoic Acids and Related Cell Wall Glycopolymers in the Gram-positive Cell Envelope". W Prokaryotic Cell Wall Compounds, 155–74. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-05062-6_5.
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"3: Acides gras mono-insaturés (oléique, palmitoléique et myristoléique) et leurs dérivés". W Un regard passionné sur les lipides et les matières grasses, 73–96. EDP Sciences, 2020. http://dx.doi.org/10.1051/978-2-7598-2075-7-006.
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"3: Acides gras mono-insaturés (oléique, palmitoléique et myristoléique) et leurs dérivés". W Un regard passionné sur les lipides et les matières grasses, 73–96. EDP Sciences, 2020. http://dx.doi.org/10.1051/978-2-7598-2075-7.c006.
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Quispe Solano, Miguel Angel, Shalin Carhuallanqui Avila, Mery Baquerizo Canchumanya, Ricardo Elvis Cortez Quintana, Emilio Fredy Yabar Villanueva, Lizve Vilcapoma Ureta, Edson Hilmer Julca Marcelo, Alejandrina Honorata Sotelo Méndez, Rodolfo Tello Saavedra i Mary Ana Luisa Porras Osorio. "Capítulo 16: Potencial polifenólico, vitamina C y capacidad antioxidante de láminas de arándano y manzana utilizando goma xantana". W Gestión del conocimiento. Perspectiva multidisciplinaria (libro 62), 321–46. Fondo Editorial de la Universidad Nacional Experimental Sur del Lago, Jesús María Semprum (UNESUR), 2023. http://dx.doi.org/10.59899/ges-cono-62-c16.
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En el contexto actual de búsqueda de alimentos funcionales y preferencia de los consumidores hacia productos naturales, como las láminas deshidratadas de pulpa de fruta, excelentes “snacks” que conservan sus cualidades nutritivas y propiedades funcionales, así como su capacidad antioxidante, se han incrementado estos últimos años, debido a los problemas de salud, como la diabetes, triglicéridos y problemas cardiovasculares. Siendo el arándano (Vaccinium corymbosum E.) y manzana (Malus domestica) frutas con alto contenido en flavonoides y antocianinas principalmente el arándano, que viene ganando gran demandada en los nuevos mercados de consumo de alimentos saludables. Siendo el objetivo evaluar el efecto de la variación de las proporciones de pulpa de arándano (Vaccinium corymbosum E.) y manzana (Malus domestica) y diferentes proporciones de goma xantana sobre las características fisicoquímicas, sensoriales, composición química, contenido de vitamina C, polifenoles totales y capacidad antioxidante de las láminas deshidratadas. Se determinó las características fisicoquímicas, evaluación química proximal, contenido de vitamina C de las láminas deshidratadas de pulpa de arándano y manzana, donde la muestra 3 (Arándano y manzana 30:70, 0.1% goma xantana, 3% sacarosa) presenta mayor aceptabilidad sensorial y cumple con los parámetros establecidos: 3.29 pH, 72.52 °Brix, 4.54 Acidez titulable (% ac. málico), presenta su composición química: humedad 11.22%, proteína 3.59%, grasa 1.13%, ceniza 7.22%, fibra 18.97% y carbohidratos 57.87%, y componentes bioactivos: contenido de vitamina C 69.39 mg de ácido ascórbico/100 g, contenido de polifenoles 149,8 mg acido gálico/100 g y la capacidad antioxidante 34.25% de Inhibición. Concluyéndose, que la variación de proporciones de pulpa de arándano y manzana y diferentes porcentajes de goma xantana influyen significativamente sobre el contenido de vitamina C, polifenoles totales y capacidad antioxidante. Siendo las láminas deshidratadas con pulpas de frutas un producto nutraceútico frente a los productos convencionales y puede ser consumida para mejorar la salud de los consumidores.
Streszczenia konferencji na temat "Acides gras 3-hydroxylés (3-AGH)"
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ALEKSEEV, Andrey, Alena Andreevna Bogdanova, Aleksandra Aleksandrovna Payuta i Natal'ya KOLESOVA. "Studying the effect of a chemical preservative on the process ensiling bean-grass grass mixture". W Multifunctional adaptive fodder production 29 (77). ru: Federal Williams Research Center of Forage Production and Agroecology, 2022. http://dx.doi.org/10.33814/mak-2022-29-77-173-177.
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The results of the influence of a chemical preservative, which includes organic acids, on the process of silage of clover-thymotheal grain mass are presented. During the study, the effect of applying a preservative in a dosage of 2 l/t, 3 l/t, 4 l/t of green mass was studied, the drug was not introduced into the control sample. On the 10th, 20th and 30th days of the silage process, pH, organic acid content, and mass fraction of lactic acid were determined according to standard methods. In the control sample, the hydrogen index was higher than in the samples with the use of starter culture. The amount of lactic acid in all samples with preservative was higher than in the control. The content of butyric acid in all experimental silos did not exceed the permissible norms, and in the control sample, its content was slightly higher. The use of chemical preservative had a positive effect on the process of silage of green mass and preservation of its quality.
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Khair, Nedaa Kamalalden. "Activity of Antibiotic Producing Bacteria Isolated from Rhizosphere Soil Region of Different Medicinal Plants". W Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0093.
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The rhizosphere soil of medicinal plants is rich in microorganisms that develop antibiotics as natural mechanism of protection against other microbes that live in their vicinity. The present study aims to explore the production of antibacterial agents from rhizosphere soil bacteria of 11 medicinal plants and determine their activity against Gram-negative (Pseudomonas aeruginosa, Escherichia coli) and Gram-positive (Bacillus cereus, Staphylococcus aureus) bacteria. Soil samples were collected and used to isolate antibiotic producing bacteria (APB). Those isolates (108) were first tested using Cross-streak method against test bacteria. Then, isolates that showed a positive antibacterial effect (12) were tested by antibiotic susceptibility test (AST) of their cell free supernatant (CFS) and their extracellular and intracellular secondary metabolites extraction which gave positive results. Staphylococcus aureus found to be the most sensitive test bacteria with inhibitory zones ranging from 13.5 - 19 mm. Moreover, combinatorial effect of isolates CFS with two organic acids (3% Acetic acid and 0.4 mg/ml Acetylsalicylic acid), two commercial antibiotics (0.016 mg/ml Augmentin and 0.128 mg/ml Doxycycline), and two pure antibiotics (10 mcg/disk Penicillin and 25mcg/disk Carbenicillin) was in vitro evaluated using AST. The combinations of CFS-carbenicillin showed a marked synergistic activity against all test bacteria. The presence of possible antibacterial agents as acetic acid, lactic acid and citric acid in CFS of APB was confirmed by HPLC analysis. Ultimately, in vitro antibacterial study for rhizosphere soil bacteria in this work suggests the possibility of using these bacterial metabolites in clinical infections caused by selected test bacteria, especially when they combine with antibiotics or organic acids.
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Telesnina, V. M. "Dynamic of vegetation composition and structure due to post-agrogenic succession (Kostroma region)". W Problems of studying the vegetation cover of Siberia. TSU Press, 2020. http://dx.doi.org/10.17223/978-5-94621-927-3-2020-37.
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The rate and direction of the post-agrogenic succession are determined by the features of agricultural land development in the past. After intensive application of organic fertilizers, as well as cattle grazing, the restoration of woody vegetation slows down, as well as the rate of appearance of forest species resistant to acidic conditions and low enrichment in nutrient elements in the grass. With the intensive application of organic fertilizers, nitrophilic herbal phytocenoses with low floristic diversity exist for a long time. Prolonged haying causes a reduction in the weed-ruderal stage while slowing down the appearance of forest species. At the initial stages of overgrowing for all types of use, the convergence of a number of floristic and ecological-coenotic characteristics of phytocenoses of deposits of a similar age was revealed in the past.
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Hu, Bo, David Marks i Xiao Sun. "Fungal bioprocessing to improve quality of pennycress meal as potential feeding ingredient for monogastric animal". W 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/izob6294.
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Pennycress is an annual cover crop in temperate North America and its seeds contain around 30% of oil and 20% of crude protein. Pennycress oil can be used for biodiesel production, while the seed meal has limited use in animal feed due to its relative high content of phenolic compounds and crude fiber. The nutritional value of pennycress meal (PM) can be improved by processing with GRAS fungal strains. In this study, three fungal strains, Rhizopus oryzae (RO), Mucor indicus (MI), and Aspergillus oryzae (AO), were used to ferment PM that contains 21% of total amino acids and 17% of structure carbohydrates. The fermentation was performed by inoculating each strain to the sterilized PM with initial moisture of 60% and incubated statically at 28 °C for 6 days. Amino acids profile, structure carbohydrates, soluble sugar, phytate, and mycotoxins including total aflatoxins, zearalenone (ZEN), and deoxynivalenol (DON) were monitored on the samples after fermentation. As compared to control without fermentation, the total amino acids were improved by 4.0% with RO and 5.9% with AO. Threonine, arginine, alanine, and lysine were significantly enriched in RO and AO treated meal. RO and MI degraded the fiber component into cellobiose, which was increased by 3 and 5.8-fold, respectively. Phytate was reduced by 46.6% with RO, 37.3% with AO, and 33.3% with MI. Compared with the control, ZEN was reduced by 39.3%, 32%, and 50% in AO, MI and RO treated meal, respectively. Total aflatoxin content was low in PM, and MI and RO treatments further reduced its content after fermentation. No significant change of DON was observed in the PM fermented by each strain. This study demonstrated the potential of using fungi to improve the feeding value of PM, which could potentially promote the plantation of oilseed crops in the region.
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Huguet, Arnaud, Eve Hellequin, Pierre Véquaud, Marina Seder-Colomina, Sylvie Collin i Adrienne Kish. "Effect of temperature and pH on the membrane lipid composition of soil Gram-negative bacteria isolates: Implications for the use of 3-hydroxy fatty acids as (paleo)environmental proxies". W Goldschmidt2023. France: European Association of Geochemistry, 2023. http://dx.doi.org/10.7185/gold2023.16169.
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ISMAILOV, Ismail Sagidovich, Nina Vladimirovna TREGUBOVA, Rashid Hasanbievich KOCHKAROV, Anna Victorovna MORGUNOVA i Natalija Alecseevna DRIZHD. "THE RELATIONSHEEP OF AMINO ACID METABOLISM WITH PRODUCTIVITY OF GROWING YOUNG SHEEP". W RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.125.
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A number of studies on digestion of the ruminants have shown the process of synthesis of all the essential amino acids in the rumen (Abu Fadel, 2004; Trukhachev, V., Zlidnev, N. 2008). However, according to some researches, microbial protein is deficient in methionine and lysine. This assumption also proves the need for further study of the influence of balanced amino acids to these diets on the growth, development and productive performance of the ruminants. Scientific approbation of the issues related to establishing the requirements of young sheep in lysine and methionine with cystine and development of recommendations for their proper balance in animal rations have been conducted along with a series of physiological, scientific and practical experiments. For this purpose, we used the following research methods: preparative, analytical, measuring and calculating. Zootechnical evaluation of young sheep’s diet with different levels of lysine and methionine with cysteine has been conducted, and influence of these components on growth, development, metabolism, the use of amino acids and wool productivity have been studied. The importance of studying the content of amino acids in plasma is evident because they are the indicators of protein metabolism in the animals’ organism and represent themselves the exchange fund when used in the biochemical transformations in the process of updating the protein of the body tissues and the synthesis of animal products. Increase in young sheep’s diet of lysine and methionine can improve their productivity, reduce the cost of feed energy and improve biochemical indexes of meat, taking into account the optimization of its amino acid composition. Efficiency increase of young sheep during the process of the individual development is linked to conditions of feeding and in particular the usefulness of a protein food, which is primarily determined by sufficient intake of essential amino acids - lysine and methionine with cystine. Thus, the inclusion in the diet of growing young sheep some amount of synthetic amino acids – 6–8 grams of lysine and 3–4 g of methionine per 1 fodder unit, enhances oxidation-reduction processes, increase productivity, i.e. wool yield and other indicators. The content of free amino acids in plasma directly depends on their availability in feed. The use of synthetic amino acids (lysine, methionine and cystine) contributed to the increase of their content in a free state in the blood serum, indicating their increased demand in sheep. With the use of different doses of synthetic amino acids (lysine, methionine, cystine) in the diets of young sheep it has been found that the organization of optimum conditions of feeding, care and management of sheep in winter season help to avoid abrupt changes in the structure of the skin, to ensure the normal development of the histological structure and morphogenetic processes.)
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S, Wimalasiri, i Somasiri S.C. "Ensiled Fruit Peels of Pineapple (Ananas comosus) and Papaya (Carica papaya) as an Animal Feed". W 2nd International Conference on Agriculture, Food Security and Safety. iConferences (Pvt) Ltd, 2021. http://dx.doi.org/10.32789/agrofood.2021.1003.
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One of the major issues for the development of the livestock sector in Sri Lanka is the unavailability of quality animal feeds. Thus, this study was carried out to prepare value-added silages using fruit peels for feeding livestock. Silage has been prepared using pineapple (Ananas comosus) and papaya (Carica papaya) fruit peels obtained from a fruit processing factory in Sri Lanka. Ensiling was done either in fruit peels only or in different combinations of fruit peels and chopped Hybrid Napier (CO-3 Pennisetum perpureum × Pennisetum americarnum) grass. The experimental design was a completely Randomized Design having ten treatments (T1 to T10) with two replicates per each. The treatments were T1 Papaya 100%, T2 Pineapple 100%, T3 Grass 100 %, T4 Pineapple 75%+ Papaya 25%, T5 Pineapple 50%+ Papaya 50%, T6 Pineapple 25%+ Papaya 75%, T7 Pineapple 20%+Papaya 70%+ Grass 10%, T8 Pineapple 30%+ Papaya 50%+ Grass 20%, T9 Pineapple 70%+ Papaya 20%+ Grass 10%, and T10 Pineapple 50%+ Papaya 30%+ Grass 20%. The fruit peels and grass were dried under shade, chopped, and mixed according to the different treatments. After 21days, representative silage samples from each treatment were analyzed for nutrient content, colour, odour, pH, and Ammonium Nitrogen (NH3N) content. The colour of all silages ranged from olive green to orange. All the treatments had a fruity smell. The pH values ranged from 3.41 to 4.04 in all treatments. The highest (p<0.05) crude protein (CP) content was in T3, and the lowest (p<0.05) was observed in T4 and T5. The highest (p<0.05) acid detergent fibre (ADF) contents were in T3, T8, and T10, and the lowest (p<0.05) was in T5 and T6. The highest (p<0.05) neutral detergent fibre (NDF) content was in T9 (44.00±0.02%) and the lowest (p<0.05) in T2. The NH3N was not present in any of the treatments. Based on CP, ADF, and NDF contents, T1, T7, T8, T9, and T10 were selected for further studies with animals to select the best treatment.
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Sánchez Mantica, Damián Gabriel. "Evaluación de la calidad en mieles comerciales de la provincia de Mendoza". W VI CONGRESO INVESTIGACIÓN, DESARROLLO E INNOVACIÓN DE LA UNIVERSIDAD INTERNACIONAL DE CIENCIA Y TECNOLOGÍA. Universidad Internacional de Ciencia y Tecnología, 2022. http://dx.doi.org/10.47300/978-9962-738-04-6-62.
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Introducción: actualmente la producción apícola representa un sector socio económico de gran interés, es propicio tener un conocimiento profundo de la matriz del alimento, su comportamiento, variables y características particulares. Objetivo: se enmarcaron en evaluar la calidad de mieles comercializadas en la Provincia de Mendoza y verificar su cumplimiento con la legislación vigente respecto a los parámetros de calidad estándares en miel. Materiales y Métodos: se aplicaron metodologías de muestreo, de preparación y técnicas analíticas oficiales enmarcadas por Código Alimentario Argentino a un rango de 30 muestras recolectadas entre 2018 y 2020. Resultados y Discusión: los valores analíticos promedio obtenidos se encuentran dentro de los parámetros legislados: Azúcares reductores 71,41 % (SD 14,665), Sacarosa aparente 0,82 % (SD 0,275), Humedad 16,14 % (SD 0,375), pH 4,068 (SD 0,424), Acidez total 15,741 meq ácido glucónico/kg miel (SD 9,518), Cenizas 0,3161 % (SD 0,098), Sólidos Insolubles en agua 0,07 % (SD 0,029), HMF 19,83 mg/kg (SD 7,125), Índice de diastasas (ID) 32,46 °Gothe (SD 18,962), Dextrinas totales < 3 %. El 13% de las muestras evocaron diferencias con los límites establecidos, siendo correlativos entre los diversos parámetros, es decir, muestras que contienen menor ID, presentan un mayor contenido de HMF. La relación de humedad y azúcares son totalmente concordantes, la relación acidez, pH y cenizas también. Determinaciones en relación con adulteraciones como dextrinas totales, corresponden a valores normales. Conclusión: las mieles comercializadas en la Provincia de Mendoza presentaron una buena calidad, los parámetros fisicoquímicos permitieron poder evaluar el estado de las mismas.
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Fadil MOUSA, Enaam, i Ibtissam Khalifa JASSIM. "SYNTHESIS ,CHARACTERIZATION AND BIOLOGICAL ACTIVITY STUDY OF SOME HETEROCYCLIC COMPOUNDS". W IV.International Scientific Congress of Pure,Appliedand Technological Sciences. Rimar Academy, 2022. http://dx.doi.org/10.47832/minarcongress4-18.
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Heterocycles are an important class of organic compounds because of their applications in medicines and industrial fields. Therefore our study included preparation of these compound such as oxazepine and quinazoline rings, which were prepared through two steps: The first step included the reaction of the Schiff bases derived from sulfamethaxazole (1-4) with each of phthalic anhydride and 3- nitrophthalic anhydride for the preparation of oxazepines (5-12) .While the second step included the preparation of quinazoline compounds (13-16) from the reaction of Schiff bases (1-4) with anthranilic acid using dry benzene as a medium and solvent for the reaction. All prepared compounds were characterized by using infrared,proton- nuclear magnetic resonance, mass techniques and melting points, and their purity was determined by thin layer chromatography technique also screened the biological activity of some of these prepared compounds by using two types of bacteria Gram-positive and negative . The results showed that these compounds have a good inhibition against these organisms
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Jelinek, Miroslav, Alexandra Voss, Tomáš Kocourek, Mahsa Mozafari, Veronika Vymetalová, Marketa Zezulová, Petr Písarík, Cyril Popov i Jan Mikšovský. "Comparison of surface properties of DLC and ultrananocrystalline diamond films with respect to their bio-applications". W 13th International Conference on Plasma Surface Engineering September 10 - 14, 2012, in Garmisch-Partenkirchen, Germany. Linköping University Electronic Press, 2013. http://dx.doi.org/10.3384/wcc2.376-379.
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DLC layers are entirely amorphous or contain micro- or nanocrystalline diamond or graphite and possess a disordered structure with a mixture of carbon bonding configurations. Furthermore, DLC can be hydrogen free (a-C) or containing hydrogen (hydrogenated amorphous carbon (a-C:H)). DLC films exhibit excellent physical and chemical properties, as well as high level of biocompatibility [1]. The films are dense, mechanically hard, smooth, abrasion resistant, IR transparent, chemically inert, resistant to attack by both acids and bases, have a low coefficient of friction, low wear rate, and are biocompatible and thromboresistant [2-3]. DLC coatings can be adherent on various biomaterials; neither toxicity toward certain living cells nor inflammatory response or loss of cell integrity were reported [4]. DLC shows an excellent hemocompatibility, a decreased tendency of thrombus formation and coated heart valves and stents are already commercially available [5]. The properties of the DLC coatings depend strongly on the hydrogen content and sp3/sp2 ratio which, in turn, depend on the deposition process and its parameters. The range of the properties of the DLC produced by different methods and under different process parameters is considerable. Diamond is a material with quite a number of excellent properties [6], like extreme hardness, high elastic modulus, high wear resistance, optical transparency in a broad spectral range, resistivity controllable by the level of dopants, etc. which make it a promising candidate for diverse applications. Due to its outstanding electrochemical properties, superior chemical inertness and biocompatibility, artificially grown diamond has been recognised as an extremely attractive material for both (bio-)chemical sensing and as an interface to biological systems. This holds for all forms of diamond: monocrystalline (natural or artificial) and poly- (PCD), nano- (NCD) and ultrananocrystalline (UNCD) films. In the current work the surface and antibacterial properties of DLC and UNCD films including the nature of the surface bonding and termination, wettability, surface energy and tests with Gram-positive and Gram-negative bacteria were studied and discussed.
Raporty organizacyjne na temat "Acides gras 3-hydroxylés (3-AGH)"
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Sessa, Guido, i Gregory Martin. Role of GRAS Transcription Factors in Tomato Disease Resistance and Basal Defense. United States Department of Agriculture, 2005. http://dx.doi.org/10.32747/2005.7696520.bard.
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The research problem: Bacterial spot and bacterial speck diseases of tomato are causedby strains of Xanthomonas campestris pv. vesicatoria (Xcv) and Pseudomonas syringae pv.tomato (Pst), respectively. These bacteria colonize aerial parts of the plant and causesignificant losses in tomato production worldwide. Protection against Xcv and Pst bycultural practices or chemical control has been unsuccessful and there are only limitedsources of genetic resistance to these pathogens. In previous research supported in part byBARD IS-3237-01, we extensively characterized changes in tomato gene expression uponthe onset of spot and speck disease resistance. A remarkable finding of these studies wasthe inducibility in tomato leaves by both Xcv and Pst strains of genes encodingtranscriptional activator of the GRAS family, which has not been previously linked todisease resistance. Goals: Central goals of this research were to investigate the role of GRAS genes in tomatoinnate immunity and to assess their potential use for disease control.Specific objectives were to: 1. Identify GRAS genes that are induced in tomato during thedefense response and analyze their role in disease resistance by loss-of-function experiments.2. Overexpress GRAS genes in tomato and characterize plants for possible broad-spectrumresistance. 3. Identify genes whose transcription is regulated by GRAS family. Our main achievements during this research program are in three major areas:1. Identification of tomato GRAS family members induced in defense responses andanalysis of their role in disease resistance. Genes encoding tomato GRAS family memberswere retrieved from databases and analyzed for their inducibility by Pst avirulent bacteria.Real-time RT-PCR analysis revealed that six SlGRAS transcripts are induced during theonset of disease resistance to Pst. Further expression analysis of two selected GRAS genesshowed that they accumulate in tomato plants in response to different avirulent bacteria orto the fungal elicitor EIX. In addition, eight SlGRAS genes, including the Pst-induciblefamily members, were induced by mechanical stress in part in a jasmonic acid-dependentmanner. Remarkably, SlGRAS6 gene was found to be required for tomato resistance to Pstin virus-induced gene silencing (VIGS) experiments.2. Molecular analysis of pathogen-induced GRAS transcriptional activators. In aheterologous yeast system, Pst-inducible GRAS genes were shown to have the ability toactivate transcription in agreement with their putative function of transcription factors. Inaddition, deletion analysis demonstrated that short sequences at the amino-terminus ofSlGRAS2, SlGRAS4 and SlGRAS6 are sufficient for transcriptional activation. Finally,defense-related SlGRAS proteins were found to localize to the cell nucleus. 3. Disease resistance and expression profiles of transgenic plants overexpressing SlGRASgenes. Transgenic plants overexpressing SlGRAS3 or SlGRAS6 were generated. Diseasesusceptibility tests revealed that these plants are not more resistant to Pst than wild-typeplants. Gene expression profiles of the overexpressing plants identified putative direct orindirect target genes regulated by SlGRAS3 and SlGRAS6. Scientific and agricultural significance: Our research activities established a novel linkbetween the GRAS family of transcription factors, plant disease resistance and mechanicalstress response. SlGRAS6 was found to be required for disease resistance to Pstsuggesting that this and possibly other GRAS family members are involved in thetranscriptional reprogramming that takes place during the onset of disease resistance.Their nuclear localization and transcriptional activation ability support their proposed roleas transcription factors or co-activators. However, the potential of utilizing GRAS familymembers for the improvement of plant disease resistance in agriculture has yet to bedemonstrated.
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Chefetz, Benny, Baoshan Xing, Leor Eshed-Williams, Tamara Polubesova i Jason Unrine. DOM affected behavior of manufactured nanoparticles in soil-plant system. United States Department of Agriculture, styczeń 2016. http://dx.doi.org/10.32747/2016.7604286.bard.
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The overall goal of this project was to elucidate the role of dissolved organic matter (DOM) in soil retention, bioavailability and plant uptake of silver and cerium oxide NPs. The environmental risks of manufactured nanoparticles (NPs) are attracting increasing attention from both industrial and scientific communities. These NPs have shown to be taken-up, translocated and bio- accumulated in plant edible parts. However, very little is known about the behavior of NPs in soil-plant system as affected by dissolved organic matter (DOM). Thus DOM effect on NPs behavior is critical to assessing the environmental fate and risks related to NP exposure. Carbon-based nanomaterials embedded with metal NPs demonstrate a great potential to serve as catalyst and disinfectors. Hence, synthesis of novel carbon-based nanocomposites and testing them in the environmentally relevant conditions (particularly in the DOM presence) is important for their implementation in water purification. Sorption of DOM on Ag-Ag₂S NPs, CeO₂ NPs and synthesized Ag-Fe₃O₄-carbon nanotubebifunctional composite has been studied. High DOM concentration (50mg/L) decreased the adsorptive and catalytic efficiencies of all synthesized NPs. Recyclable Ag-Fe₃O₄-carbon nanotube composite exhibited excellent catalytic and anti-bacterial action, providing complete reduction of common pollutants and inactivating gram-negative and gram-positive bacteria at environmentally relevant DOM concentrations (5-10 mg/L). Our composite material may be suitable for water purification ranging from natural to the industrial waste effluents. We also examined the role of maize (Zeamays L.)-derived root exudates (a form of DOM) and their components on the aggregation and dissolution of CuONPs in the rhizosphere. Root exudates (RE) significantly inhibited the aggregation of CuONPs regardless of ionic strength and electrolyte type. With RE, the critical coagulation concentration of CuONPs in NaCl shifted from 30 to 125 mM and the value in CaCl₂ shifted from 4 to 20 mM. This inhibition was correlated with molecular weight (MW) of RE fractions. Higher MW fraction (> 10 kDa) reduced the aggregation most. RE also significantly promoted the dissolution of CuONPs and lower MW fraction (< 3 kDa) RE mainly contributed to this process. Also, Cu accumulation in plant root tissues was significantly enhanced by RE. This study provides useful insights into the interactions between RE and CuONPs, which is of significance for the safe use of CuONPs-based antimicrobial products in agricultural production. Wheat root exudates (RE) had high reducing ability to convert Ag+ to nAg under light exposure. Photo-induced reduction of Ag+ to nAg in pristine RE was mainly attributed to the 0-3 kDa fraction. Quantification of the silver species change over time suggested that Cl⁻ played an important role in photoconversion of Ag+ to nAg through the formation and redox cycling of photoreactiveAgCl. Potential electron donors for the photoreduction of Ag+ were identified to be reducing sugars and organic acids of low MW. Meanwhile, the stabilization of the formed particles was controlled by both low (0-3 kDa) and high (>3 kDa) MW molecules. This work provides new information for the formation mechanism of metal nanoparticles mediated by RE, which may further our understanding of the biogeochemical cycling and toxicity of heavy metal ions in agricultural and environmental systems. Copper sulfide nanoparticles (CuSNPs) at 1:1 and 1:4 ratios of Cu and S were synthesized, and their respective antifungal efficacy was evaluated against the pathogenic activity of Gibberellafujikuroi(Bakanae disease) in rice (Oryza sativa). In a 2-d in vitro study, CuS decreased G. fujikuroiColony- Forming Units (CFU) compared to controls. In a greenhouse study, treating with CuSNPs at 50 mg/L at the seed stage significantly decreased disease incidence on rice while the commercial Cu-based pesticide Kocide 3000 had no impact on disease. Foliar-applied CuONPs and CuS (1:1) NPs decreased disease incidence by 30.0 and 32.5%, respectively, which outperformed CuS (1:4) NPs (15%) and Kocide 3000 (12.5%). CuS (1:4) NPs also modulated the shoot salicylic acid (SA) and Jasmonic acid (JA) production to enhance the plant defense mechanisms against G. fujikuroiinfection. These results are useful for improving the delivery efficiency of agrichemicals via nano-enabled strategies while minimizing their environmental impact, and advance our understanding of the defense mechanisms triggered by the NPs presence in plants.
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Swanson, David, i Celia Hampton-Miller. Drained lakes in Bering Land Bridge National Preserve: Vegetation succession and impacts on loon habitat. National Park Service, styczeń 2023. http://dx.doi.org/10.36967/2296593.
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The northern coastal plain of Bering Land Bridge National Preserve (BELA) lost lakes at an alarming rate over the first two decades of this century, including four lakes over 100 ha in size in 2018-2019 alone. To understand the effects of these lake drainages, we sampled vegetation of these lakes in 2019 (a reconnaissance visit) and 2021 (for the installation of permanent vegetation monitoring plots). We used these data to summarize the changes that occurred in the first three years after drainage, and to create vegetation maps from 3-m resolution satellite images coinciding with the visit dates. We used time series of these satellite images to study the rate of drainage and vegetation colonization on the lakes. We analyzed our existing data from older drained lake basins (estimated to be more than 200 years since drainage) and reviewed the literature on vegetation change in drained lakes to understand the vegetation changes that are likely in the future. Finally, we used a model of lake occupancy by loons developed by Mizel et al. (2021) to predict the effect of the 2018-2019 lake drainages on available loon habitat, using both our detailed maps of the four sampled drained lakes, and also data on all drained lakes over most of northern BELA derived from Landsat satellite images. Our results show that the four study lakes drained early in the summer, before the end of June, in 2018 (3 lakes) and 2019 (one lake). A combination of record warm weather and heavy snowfall made 2018 and 2019 especially favorable for lake drainage: thaw subsidence probably enlarged existing drainage outlet channels from the lakes, and large amounts of spring snowmelt runoff deepened the outlet channels by thermal erosion (the combination of thaw and erosion). Drainage exposed moist loamy sediment on the lake bottoms that was rapidly colonized by plants. Substantial vegetation cover developed by late summer in the same year as lake drainage in one lake, in the first post-drainage summer in a second lake, and during the 2nd year after drainage in the remaining two lakes. The first vegetation communities to develop consisted of just one or two dominant species, notably Eleocharis acicularis (spike rush), Equisetum arvense (horsetail), and/or Tephroseris palustris (mastodon flower). Other important early species were Arctophila fulva (pendant grass) and Rorippa palustris (yellow cress). By year 3, the communities had become more diverse, with significant cover by taller wetland graminoid species, including A. fulva, Eriophorum scheuchzeri, and Carex aquatilis. Frozen soil was observed in most locations on the lakes in July of 2021, suggesting that permafrost was forming on the lake bottoms. Comparison of the three-year trends in vegetation change with data from older lake basins suggest that ultimately most lake basins will develop wet tundra communities dominated by Carex aquatilis and mosses, with various low shrub species on acid, peat-dominated soils and permafrost; however, this process should take several centuries. The loon habitat model suggests that drainage essentially eliminated the potential habitat for Yellow-billed Loons on the four study lakes, because the residuals ponds were too small for Yellow-billed Loons to take flight from. A total of 17 lakes drained in northern BELA in 2018-2019. As a result, the potential Yellow-billed Loon nesting habitat in northern BELA probably decreased by approximately 2%, while habitat for Pacific Loons decreased less, by about 0.6%. Habitat for the more abundant Red-throated Loons probably increased slightly as a result of lake drainage, because of their ability to use the small residual ponds created by lake drainage.
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Splitter, Gary A., Menachem Banai i Jerome S. Harms. Brucella second messenger coordinates stages of infection. United States Department of Agriculture, styczeń 2011. http://dx.doi.org/10.32747/2011.7699864.bard.
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Aim 1: To determine levels of this second messenger in: a) B. melitensiscyclic-dimericguanosinemonophosphate-regulating mutants (BMEI1448, BMEI1453, and BMEI1520), and b) B. melitensis16M (wild type) and mutant infections of macrophages and immune competent mice. (US lab primary) Aim 2: To determine proteomic differences between Brucelladeletion mutants BMEI1453 (high cyclic-dimericguanosinemonophosphate, chronic persistent state) and BMEI1520 (low cyclicdimericguanosinemonophosphate, acute virulent state) compared to wild type B. melitensisto identify the role of this second messenger in establishing the two polar states of brucellosis. (US lab primary with synergistic assistance from the Israel lab Aim 3: Determine the level of Brucellacyclic-dimericguanosinemonophosphate and transcriptional expression from naturally infected placenta. (Israel lab primary with synergistic assistance from the US lab). B. Background Brucellaspecies are Gram-negative, facultative intracellular bacterial pathogens that cause brucellosis, the most prevalent zoonosis worldwide. Brucellosis is characterized by increased abortion, weak offspring, and decreased milk production in animals. Humans are infected with Brucellaby consuming contaminated milk products or via inhalation of aerosolized bacteria from occupational hazards. Chronic human infections can result in complications such as liver damage, orchitis, endocarditis, and arthritis. Brucellaspp. have the ability to infect both professional and non-professional phagocytes. Because of this, Brucellaencounter varied environments both throughout the body and within a cell and must adapt accordingly. To date, few virulence factors have been identified in B. melitensisand even less is known about how these virulence factors are regulated. Subsequently, little is known about how Brucellaadapt to its rapidly changing environments, and how it alternates between acute and chronic virulence. Our studies suggest that decreased concentrations of cyclic dimericguanosinemonophosphate (c-di-GMP) lead to an acute virulent state and increased concentrations of c-di-GMP lead to persistent, chronic state of B. melitensisin a mouse model of infection. We hypothesize that B. melitensisuses c-di-GMP to transition from the chronic state of an infected host to the acute, virulent stage of infection in the placenta where the bacteria prepare to infect a new host. Studies on environmental pathogens such as Vibrio choleraeand Pseudomonas aeruginosasupport a mechanism where changes in c-di-GMP levels cause the bacterium to alternate between virulent and chronic states. Little work exists on understanding the role of c-di-GMP in dangerous intracellular pathogens, like Brucellathat is a frequent pathogen in Israeli domestic animals and U.S. elk and bison. Brucellamust carefully regulate virulence factors during infection of a host to ensure proper expression at appropriate times in response to host cues. Recently, the novel secondary signaling molecule c-di-GMP has been identified as a major component of bacterial regulation and we have identified c-di-GMP as an important signaling factor in B. melitensishost adaptation. C. Major conclusions, solutions, achievements 1. The B. melitensis1453 deletion mutant has increased c-di-GMP, while the 1520 deletion mutant has decreased c-di-GMP. 2. Both mutants grow similarly in in vitro cultures; however, the 1453 mutant has a microcolony phenotype both in vitro and in vivo 3. The 1453 mutant has increased crystal violet staining suggesting biofilm formation. 4. Scanning electron microscopy revealed an abnormal coccus appearance with in increased cell area. 5. Proteomic analysis revealed the 1453 mutant possessed increased production of proteins involved in cell wall processes, cell division, and the Type IV secretion system, and a decrease in proteins involved in amino acid transport/metabolism, carbohydrate metabolism, fatty acid production, and iron acquisition suggesting less preparedness for intracellular survival. 6. RNAseq analysis of bone marrow derived macrophages infected with the mutants revealed the host immune response is greatly reduced with the 1453 mutant infection. These findings support that microlocalization of proteins involved in c-di-GMP homeostasis serve a second messenger to B. melitensisregulating functions of the bacteria during infection of the host.