Journal articles: 'Acide aminé libre'

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Poirier-Littré, MF. "Implication du métabolisme de la sérotonine dans la dépression." Psychiatry and Psychobiology 5, no. 3 (1990): 179–85. http://dx.doi.org/10.1017/s0767399x00003473.

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RésuméLa découverte simultanée de l’action antidépressive de l’imipramine ainsi que la mise en évidence d’une action sur la transmission sérotoninergique au niveau du système nerveux central a renforcé l’idée d’une perturbation biologique concomitante des dépressions. Devant l’impossibilité d’accéder in vivo aux structures cérébrales, ces explorations ont porté en périphérie sur la mesure du neurotransmetteur, de son précurseur le tryptophane, de son catabolite le 5 HIAA, des activités enzymatiques de synthèse et de son catabolisme, de sa vitesse de capture ou de stockage. Dans les dépressions, le tryptophane libre plasmatique serait abaissé chez les patients par rapport aux sujets témoins, mais d’autres auteurs ne retrouvent pas de modification voire même une augmentation de ce paramètre. Une distribution bimodale du tryptophane chez les sujets dépressifs et une variation saisonnière différente de ses taux plasmatiques entre sujets dépressifs et témoins sont deux explications possibles de ces résultats contradictoires. L’anorexie fréquemment présentée par les patients déprimés pourrait entraîner une baisse de cet acide aminé chez ces patients. À la suite des travaux d’Ashcroft et al en 1966, de nombreuses études ont montré que la concentration de 5 HIAA dans le LCR est abaissée chez certains déprimés comparativement à des témoins. Cette diminution de 5 HIAA lombaire pourrait refléter une diminution du turnover de la sérotonine. En fait, elle n’a pas été mise en évidence par tous les auteurs. Ceci pourrait s’expliquer par la mise en évidence d’une distribution bimodale du 5 HIAA chez les patients déprimés. Environ 30% des patients présenterait une baisse du taux de 5 HIAA dans le LCR et serait caractérisé par des conduites suicidaires plus fréquentes, une agressivité plus marquée. Les concentrations de sérotonine et de 5 HIAA ont été mesurées postmortem chez des patients décédés après une tentative de suicide de même que chez des patients décédés d’autres causes. Ces études qui ne sont toutefois pas concordantes tendent à mettre en évidence une diminution des taux cérébraux de sérotonine et de 5 HIAA. Il semble bien que les résultats soient beaucoup plus nuancés selon les régions explorées et que de nombreux facteurs non spécifiques de variation soient à prendre en compte. Cette diminution des taux cérébraux de 5 HT chez les suicidés « peut aussi bien résulter d’une activation du turn-over de I’antine que d’une diminution de sa synthèse » (Tissot, 1975). Divers auteurs ont relevé une baisse significative du taux de la sérotonine sérique chez les patients déprimés majeurs. Environ 60% des travaux montre une diminution des concentrations plaquettaires en 5HT. Après quelques travaux négatifs n’utilisant pas de faibles concentrations de substrats, Tuomisto et Tukiainen (cité in Loo, 1987) ont été les premiers à mettre en évidence une diminution de la capture plaquettaire de 5 HT chez des patients déprimés. Depuis, un consensus semble s’être établi sur cette baisse d’activité chez les déprimés endogènes. Tous ces résultats doivent être interprétés avec une grande prudence. Les modifications objectivées sont inconstantes et variables et it reste difficile de déterminer si elles peuvent être considérées comme une cause ou une conséquence de la maladie. Il s’agit, très certainement, d’un chaînon intermédiaire dans la perpétuelle régulation d’un système plurifactoriel complexe aux multiples connexions.

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Hureïki, L., and J. P. Croué. "Identification par couplage CG/SM des sous-produits de chloration de deux acides aminés libres, la proline et la méthionine." Revue des sciences de l'eau 10, no. 2 (April 12, 2005): 249–64. http://dx.doi.org/10.7202/705280ar.

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L'objectif de ces travaux a consiste en l'identification des sous-produits de chloration de deux acides aminés libres, la proline et la méthionine, structures reconnues pour leur grande réactivité avec le chlore. Les expériences ont été conduites a pH 8 pour un taux de chlore fixe à 8 moles de chlore par mole d'acide aminé et un temps de contact de 72 heures. Les sous-produits de chloration ont été extraits successivement par le pentane et le diethyl éther (pH acide et pH basique, extraction suivie d'une dérivation au diazométhane) et identifiés par couplage CG/SM. L'essentiel des sous-produits de chloration identifiés a été observé dans l'extrait éthéré obtenu à pH acide, que ce soit pour la proline ou la méthionine. Les acides dichloroacétique et trichloroacétique, composés retrouvés dans les eaux de surface désinfectées au chlore, ont été détectés pour les deux molécules étudiées. Les travaux effectués avec la proline ont permis d'identifier également la N- chlorodichloroacétamide et la N-chlorotrichloroacétamide. On peut noter également la formation de quelques chloroacides présentant un groupement terminal aldehyde ou nitrile caractéristique, ainsi que des composeé à structure pyrrole. En ce qui concerne la méthionine, les analyses par couplage CG/SM ont permis d'identifier quelques composés organiques chlorosoufrés comme le chlorure de méthyle sulfonyle, le chlorure de chlorométhylesulfonyle et le dichloro-1,1 diméthyle sulfonyle, ainsi que du soufre moléculaire S8.

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Bouarab, L., G. Gourbigot, M. Simon, Y. De Roeck-Holtzhauer, and M. Loudiki. "Composition en acides aminés libres et combinés et en vitamines de la microalgue Micractinium Pusillum Fres. issue d'un lagunage naturel." Revue des sciences de l'eau 18, no. 4 (April 12, 2005): 471–83. http://dx.doi.org/10.7202/705568ar.

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Dans ce travail est présentée la composition biochimique en acides aminés (AA) libres et combinés et en vitamines de Micractinium pusillum isolée à partir du lagunage naturel expérimental de Ouarzazate où cette microalgue prolifère pendant la période chaude. M. pusillum est produite en culture en vrac, sur milieu synthétique, dans des conditions de lumière et de température fixes. Cette étude révèle la richesse de M. pusillum en acides aminés combinés qui constituent environ 59% de sa matière sèche. Les acides aminés libres forment 3,4% de cette matière. Dix-sept acides aminés et quatre vitamines (D3, B2, B3, et B12) ont été déterminés chez cette microalgue.

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LE FLOC’H, N., and B. SEVE. "Le devenir des protéines et des acides aminés dans l’intestin du porc : de la digestion à l’apparition dans la veine porte." INRAE Productions Animales 13, no. 5 (October 22, 2000): 303–14. http://dx.doi.org/10.20870/productions-animales.2000.13.5.3798.

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La digestion intestinale des protéines alimentaires fait intervenir des protéases d’origine pancréatique et des peptidases intestinales. Les produits de la digestion sont constitués d’acides aminés libres et de peptides relativement abondants. Acides aminés et peptides sont transportés dans l’entérocyte où ces derniers subissent une hydrolyse. Les acides aminés libres présents dans la veine porte présentent un profil bien différent de celui des protéines alimentaires. En effet, le métabolisme intestinal des acides aminés est très actif. Afin d’assurer la synthèse des protéines constitutives et sécrétées, l’intestin prélève des acides aminés à la fois dans la lumière intestinale et dans le sang artériel. Cet organe renouvelle plus de 50 % de ses protéines par jour et la synthèse de protéines bien particulières comme les mucines engendre des besoins élevés en certains acides aminés comme la thréonine. L’intestin est le principal tissu utilisant la glutamine artérielle et le glutamate alimentaire. Le catabolisme intestinal de ces acides aminés produit de l’alanine, de l’acide aspartique, de la proline et, par l’intermédiaire des enzymes du cycle de l’urée, de l’ornithine, de la citrulline et de l’arginine. Les acides aminés indispensables n’échapperaient pas non plus au catabolisme intestinal. Le rôle de l’intestin ne se limite donc pas à la digestion des protéines et à l’absorption des acides aminés. Son métabolisme modifie profondément la disponibilité des acides aminés alimentaires pour le reste de l’organisme.

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Moureau, Corinne E., and Hubert J. Ceccaldi. "Variations circadiennes des acides aminés libres de l'hemolymphe de Penaeus japonicus." Biochemical Systematics and Ecology 13, no. 1 (January 1985): 35–40. http://dx.doi.org/10.1016/0305-1978(85)90010-9.

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LECLERCQ, B., and S. TESSERAUD. "Possibilités de réduction des rejets azotés en aviculture." INRAE Productions Animales 6, no. 3 (June 28, 2020): 225–36. http://dx.doi.org/10.20870/productions-animales.1993.6.3.4203.

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Il est possible de réduire les pertes d’azote, sources potentielles de pollution, en élevage avicole, en ayant recours soit à un usage plus développé des acides aminés industriels soit à des génotypes de poulets utilisant plus efficacement les acides aminés alimentaires. La première possibilité se heurte encore à quelques difficultés qui relèvent soit d’une mauvaise connaissance des besoins exacts en acides aminés limitants autres que la méthionine et la lysine, soit d’une légère toxicité des concentrations élevées des acides aminés libres des aliments. On peut, pour le moment, espérer une réduction de 10% des rejets d’azote par cette technique sans pertes de performances. Une supplémentation plus importante, si elle ne réduisait pas la vitesse de croissance et l’efficacité alimentaire, pourrait conduire à une baisse de 35% des rejets d’azote. L’utilisation de génotypes transformant plus efficacement les acides aminés alimentaires en protéines corporelles pourrait permettre une réduction de 15% des rejets d’azote. Ces génotypes présentent probablement des changements de besoins relatifs en acides aminés (protéine idéale). Globalement ces deux approches laissent espérer une réduction maximum de 50% des pertes d’azote en élevage avicole intensif. Dès à présent elles peuvent contribuer à les diminuer de 25%.

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Cheptanaru, L., C. Babiuc, and S. Popa. "Profil sérique des acides aminés libres et hypermétabolisme chez les patients lupiques." La Revue de Médecine Interne 28 (June 2007): 130. http://dx.doi.org/10.1016/j.revmed.2007.03.257.

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Fincham, D. A., D. K. Mason, and J. D. Young. "Characterization of a novel Na+-independent amino acid transporter in horse erythrocytes." Biochemical Journal 227, no. 1 (April 1, 1985): 13–20. http://dx.doi.org/10.1042/bj2270013.

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Horse erythrocytes are polymorphic with respect to L-alanine permeability. The present investigation compared the specificity, kinetics and cation-dependence of erythrocyte amino acid transport in two groups of thoroughbred horses, those with erythrocyte L-alanine permeabilities in the range 5-15 mumol/h per litre of cells (0.2 mM extracellular L-alanine, 37 degrees C) (transport-negative type) and those with L-alanine permeabilities in the range 450-700 mumol/h per litre of cells (transport-positive type). Transport-positive cells are shown to possess a novel high-affinity, stereospecific, Na+-independent transporter selective for neutral amino acids of intermediate size. This carrier system (provisional designation asc) operates preferentially in an exchange mode and is functionally absent from erythrocytes of transport-negative-type horses.

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Szymczak, Józef. "Recherches sur la composition chimique du Phallus impudicus. I. Les acides aminés libres." Acta Mycologica 6, no. 2 (November 21, 2014): 325–27. http://dx.doi.org/10.5586/am.1970.020.

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Helgerson, S. L., S. L. Siemsen, and E. A. Dratz. "Enrichment of bacteriorhodopsin with isotopically labeled amino acids by biosynthetic incorporation in Halobacterium halobium." Canadian Journal of Microbiology 38, no. 11 (November 1, 1992): 1181–85. http://dx.doi.org/10.1139/m92-193.

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The growth of Halobacterium halobium was optimized in a chemically defined synthetic medium. Arginine, isoleucine, leucine, lysine, methionine, tyrosine, and valine were found to be essential for growth. Optimal growth rates and cell yields were obtained when the medium was also supplemented with the nonessential amino acids alanine, asparagine, glutamic acid, glycine, phenylalanine, proline, serine, and threonine. The complete synthetic medium supported the same maximum growth rate, cell yield, and production of the integral membrane protein bacteriorhodopsin as was obtained in a complex peptone-based growth medium. Using this defined synthetic medium, isotopically labeled bacteriorhodopsin was produced with several 13C-enriched amino acids. The yield of 13C-labeled bacteriorhodopsin was greater than 35 milligrams of purified protein per litre of cell culture. Key words: bacteriorhodopsin, biosynthetic isotopic labeling, synthetic culture medium, nuclear magnetic resonance.

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BALTADJIEVA, M., G. KALATZOPOULOS, V. STAMENOVA, and A. SFAKIANOS. "Composition en acides gras libres et en acides aminés de deux fromages fabriqués à partir de lait de chèvre." Le Lait 65, no. 649-650 (1985): 221–41. http://dx.doi.org/10.1051/lait:1985649-65016.

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Marangos, Chr, Anna-Celia Araujo Barbosa, and H. J. Ceccaldi. "Variations des concentrations des acides aminés libres au cours du développement larvaire dePenaeus japonicusBate (Crustacea, Decapoda, Penaeidae)." Archives Internationales de Physiologie et de Biochimie 98, no. 1 (January 1990): 41–51. http://dx.doi.org/10.3109/13813459009115736.

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Agbekodo, K. M., J. P. Croué, S. Dard, and B. Legube. "Analyse par HPLC et CG/SM des constituants du carbone organique dissous (COD), du COD biodégradable (CODB) et des composés organohalogénés (TOX) d'un perméat de nanofiltration." Revue des sciences de l'eau 9, no. 4 (April 12, 2005): 535–55. http://dx.doi.org/10.7202/705266ar.

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Pour limiter la formation de composés organohalogénés des eaux traitées et la reviviscence bactérienne des réseaux, il est important d'éliminer la majeure partie du carbone organique dissous (COD) et du carbone organique dissous biodégradable (CODB) contenus dans les eaux naturelles. Des travaux récents nous ont permis de montrer que la nanofiltration est une technologie de choix pour répondre à ces contraintes. L'objectif de cet article est de présenter à partir de travaux de laboratoire un inventaire détaillé du carbone organique résiduel d'un perméat prélevé le 21/04/93 sur le prototype industriel de nanofiltration de Méry/Oise en banlieue parisienne. Pour atteindre cet objectif il a été nécessaire de mettre en œuvre des 'techniques analytiques impliquant l'utilisation de la chromatographie liquide haute performance (CLHP) et de la chromatographie en phase gazeuse (CG) soit équipée d'un détecteur à ionisation de flamme (FID) ou d'un détecteur à capture d'électrons (ECD), soit couplée à la spectrométrie de masse (SM). Les résultats obtenus ont montré que le COD du perméat étudié est constitué d'environ 60% d'acides aminés libres et combinés, de 7% d'aldéhydes et de 10 à 20% de composés divers identifiables en CG/SM. Ces derniers composés comprennent majoritairement des acides gras aliphatiques et des acides aromatiques de faibles masses. La concentration de chacun de ces composés a été estimée à 0,3 µg l-¹ C. On peut raisonnablement penser, d'après la bibliographie que les hydrates de carbone (non analysés dans cette étude) représenteraient une part importante de COD du perméat. En outre, cette étude a montré que la part prise par les acides aminés totaux dans le CODB du perméat est importante. Seul le tiers des potentiels de formation d'organohalogénés totaux (PFTOX) a été identifié comme étant des trihaloméhanes (THM) et des acides haloascétiques. Toutefois, étant donné que les acides aminés totaux représentent à eux seuls la quasi totalité de la demande en chlore du perméat, les autres sous-produits de chloration non identifiés seraient probablement des nitriles chlorés, des chloramines et des chloroaldéhydes qui sont parmi les principaux intermédiaires réactionnels de la coloration des acides aminés.

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Van Gelder, N. M., and F. Bélanger. "Nutrition et processus d'accumulation sélective des acides aminés libres, nécessaires au développement du cerveau de I'ernbryon du Poulet." Archives Internationales de Physiologie et de Biochimie 97, no. 4 (January 1989): A265—A304. http://dx.doi.org/10.3109/13813458909105534.

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Joassart, J. M. "Etude de l'influence du jeûne sur les teneurs en acides aminés libres du plasma sanguin chez le mouton." Zeitschrift für Tierphysiologie Tierernährung und Futtermittelkunde 36, no. 1-6 (October 9, 2009): 205–10. http://dx.doi.org/10.1111/j.1439-0396.1975.tb01135.x.

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Drouet, C., A. Reboul, and M. Colomb. "Identification of a human non-interferon lymphokine activating monocyte complement biosynthesis." Biochemical Journal 263, no. 1 (October 1, 1989): 157–64. http://dx.doi.org/10.1042/bj2630157.

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A monocyte-stimulating activity produced by mitogen-induced mononuclear cells has been defined by its ability to enhance the synthesis in vitro of complement C1 subcomponents, C2 and C3. A lymphokine responsible for this activity was purified from culture supernatants of peripheral blood mononuclear cells activated by staphylococcal enterotoxin A. From 0.5 litre of supernatant the purification procedure [(NH4)2SO4 precipitation, phenyl-Sepharose chromatography and preparative electrofocusing] yielded about 100 pmol of purified lymphokine. Its pI is 7.9 and its Mr, estimated by SDS/polyacrylamide-gel electrophoresis, is 14,600, 27,000 and 56,000, the high-Mr species representing oligomeric forms of the Mr-14,600 molecule. Its amino acid analysis reveals a high percentage of hydrophobic amino acids (34%); the absence of histidine residues suggests that it is a novel monocyte-activating lymphokine. It enhances C1r and C1s biosynthesis at a pretranslational level. From its structure and activity this lymphokine appears different from gamma-interferon.

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Enders, Dieter, and Zai-Xin Chen. "Synthesis of β-Benzylsulfanyl-β-trifluoromethyl-α-amino Acids Via Michael Addition in the Presence of Et3N/LiBr." Letters in Organic Chemistry 2, no. 2 (March 1, 2005): 156–59. http://dx.doi.org/10.2174/1570178053202865.

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FLAATTEN, H. "Long-term Parenteral Nutrition Using a Mixture of Fat, Amino Acids and Carbohydrates in a Single Three-Litre Bag." Acta Anaesthesiologica Scandinavica 29 (December 1985): 81–83. http://dx.doi.org/10.1111/j.1399-6576.1985.tb02349.x.

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Marangos, Christakis, and Hubert J. Ceccaldi. "Variations des concentrations des acides aminés libres des muscles abdominaux de Penaeus japonicus et Crangon crangon au cours d'acclimatations thermiques." Biochemical Systematics and Ecology 16, no. 3 (April 1988): 333–41. http://dx.doi.org/10.1016/0305-1978(88)90020-8.

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Pedrotti, Luana Milani, and Roberto Fernandes Da Costa. "Aminoácidos de cadeia ramificada e fadiga central." Nutrição Brasil 16, no. 2 (May 11, 2017): 120–23. http://dx.doi.org/10.33233/nb.v16i2.882.

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Objetivo: Revisar na literatura a relação da suplementação alimentar utilizando aminoácidos de cadeia ramificada (Branch Chain Amino Acids ou BCAA) com a hipótese da fadiga central. Metodologia: Trata-se de uma revisão bibliográfica de caráter narrativo. Resultados: A fadiga central é uma hipótese conhecida por muitos atletas de elite. Sabe-se que esta ocorre quando é aumentada a disponibilidade de triptofano livre. Para interromper ou retardar o processo de fadiga central, estudos indicam o uso de BCAA, pois estes aumentariam a captação de triptofano na barreira hematoencefálica, diminuindo seus níveis cerebrais e, consequentemente, retardando a fadiga central. Conclusão: Estudos realizados nos últimos anos buscam confirmar a hipótese de que a suplementação alimentar com BCAA pode retardar a fadiga central, porém não há dados clínicos suficientes para a confirmação desta teoria.Palavras-chave: aminoácidos de cadeia ramificada, fadiga central, suplementação alimentar.Â

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Rérat, A., C. Simoes Nunes, P. Vaissade, and P. Vaugelade. "Absorption intestinale en présence de glucides, des acides aminés provenant de solutions de petits peptides ou d'acides aminés libres infusées dans le duodénum chez le porc éveillé." Reproduction Nutrition Développement 30, no. 1 (1990): 136. http://dx.doi.org/10.1051/rnd:19900137.

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HEPBURN, N. L., C. H. KNIGHT, C. J. WILDE, K. A. K. HENDRY, and H. GALBRAITH. "L-methionine uptake, incorporation and effects on proliferative activity and protein synthesis in bovine claw tissue explants in vitro." Journal of Agricultural Science 146, no. 1 (August 9, 2007): 103–15. http://dx.doi.org/10.1017/s0021859607007393.

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SUMMARYL-methionine is a sulphur-containing nutritionally essential amino acid. It has a number of important roles in epidermal and dermal tissues of the integument of animals. Failure of normal function of these tissues in the hoof (claw) is a cause of lameness in cattle. Little is known about quantitative relationships between post-absorptive concentrations of nutrients including sulphur-containing amino acids and uptake and utilization by epidermis and dermis of the bovine claw. These parameters were studied at the tissue level by use of an established in vitro claw explant system using tissue from cattle of beef or dairy origin and L-[35S]-labelled methionine as tracer. The results showed that uptake of L-methionine by freshly prepared solear explants in Dulbecco's Modified Eagle Medium/F-12 Nutrient Mix (DMEM/F12) (1:1) medium containing 1·0 mmol L-methionine/litre was concentrative after 5–8 min, essentially linear for up to 10 min and became curvilinear thereafter. Maximum uptake and steady state conditions were obtained at approximately 30 min. Further measurements were made following 21 h incubation in culture medium. Under conditions of varying concentrations of L-methionine and measurement of uptake after 30 min, the presence of a saturable curve, that obeyed Michaelis–Menten kinetics, was demonstrated. Values of 3·61 mmol/litre and 5·84 mmol/kg intracellular water/30 min were obtained for KM and Vmax, respectively. Uptake was not influenced by L-cysteine and L-cystine concentrations in the culture media.Similar culture and incubation conditions were used in subsequent studies of DNA and protein synthesis. These showed that rates of incorporation of L-methionine into protein fractions and stimulation of DNA synthesis measured by methyl-thymidine incorporation were dependent on L-methionine concentrations in the medium. Maximal rates occurred at approximately 50 μmol/litre, which is in the normal physiological range, and at 1% of maximum uptake capacity. Examination of histological sections by autoradiography showed localization of L-[35S]-labelled methionine in basal and suprabasal epidermal cells with limited retention in dermis. Measurement, by a range of histological, immunohistochemical, electrophoretic, western blotting and autoradiographic techniques, provided further evidence of L-methionine-dependent regulation of proliferation, differentiation and synthesis of proteins under physiological concentrations, by epidermal horn-forming cells.A key role for L-methionine is suggested in the production of horn in bovine claw. The extrapolation of these in vitro data provides guidance for strategies to optimize methionine supply to claw tissues in vivo. Such extrapolation suggests the appropriateness of delivery of systemic concentrations of 50 μmol L-methionine/litre to maximize proliferative and protein depositional activity in solear epidermis and dermis in vivo.

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Joassart, J. M. "Etude de l'influence de la nature de la ration sur les teneurs en acides aminés libres du plasma sanguin chez le mouton." Zeitschrift für Tierphysiologie Tierernährung und Futtermittelkunde 36, no. 1-6 (October 9, 2009): 199–205. http://dx.doi.org/10.1111/j.1439-0396.1975.tb01134.x.

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RÉRAT, A., C. SIMOES NUNES, P. VAISSADE, and L. ROGER. "Comparaison de deux techniques d'estimation (ninhydrine vs TNBS) de l'azote des acides aminés circulants, appliquées à l'étude de l'absorption intestinale de solutions d'acides aminés libres ou de petits peptides." Reproduction Nutrition Développement 27, no. 5 (1987): 955–66. http://dx.doi.org/10.1051/rnd:19870708.

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SAUVANT, D., J. C. ROBERT, Françoise TERNOIS, Madeleine DURON, and J. HERVIEU. "Relation entre les teneurs en acides aminés libres du sang et la production de lait chez la chèvre en 4e semaine de lactation." Reproduction Nutrition Développement 26, no. 1B (1986): 343–44. http://dx.doi.org/10.1051/rnd:19860248.

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Guilhermet, RG, J. Charrier, A. Fraysse, and R. Toullec. "Effet d'une injection intraduodénale de L-arginine sur le taux plasmatique de l'hormone de croissance (GH) et des acides aminés libres chez l'agneau." CrossRef Listing Of Deleted DOIs 43, no. 3 (1994): 307. http://dx.doi.org/10.1051/rnd:19940374.

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Guilhermet, RG, J. Charrier, A. Fraysse, and R. Toullec. "Effet d'une injection intraduodénale de L-arginine sur le taux plasmatique de l'hormone de croissance (GH) et des acides aminés libres chez l'agneau." Annales de Zootechnie 43, no. 3 (1994): 307. http://dx.doi.org/10.1051/animres:19940374.

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Sotelo, C. G., J. M. Franco, S. P. Aubourg, and J. M. Gallardo. "Changes in free amino acids of hake (Merluccius merluccius L.) muscle during frozen storage/Cambios producidos en los aminoácidos libres del músculo de merluza (Merluccius merluccius L.) durante su conservación en estado congelado." Food Science and Technology International 1, no. 1 (February 1995): 19–24. http://dx.doi.org/10.1177/108201329500100103.

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The effect of storage at subzero temperatures (-5°C, -12°C, and -20°C) on hake ( Merluccius merluccius L.) muscle free-amino acid fraction was evaluated. A significant increase in free aspartic acid, serine, threonine, arginine, β-alanine, tyrosine, methionine, valine, phenylalanine, isoleucine, leucine, and lysine was found at -5°C, whereas at -12°C, a significant decrease in free glutamic acid, glycine, methyl-histidine, β-alanine, taurine, alanine, and leucine was the most noticeable. No changes in the free amino acid fraction were observed at -20°C. Activity of different kind of enzymes, aminopeptidases, aminoacid deaminases, and decarboxylases might be involved in the changes observed at -5°C and -12°C.

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Kehrer, Armin, Shi-qi Dou, and Alarieh Weiss. "The Electric Field Gradient at the Site of the Halogen Ion and Structure of Amino Acid Hydrobromides and Hydroiodides." Zeitschrift für Naturforschung A 47, no. 7-8 (August 1, 1992): 887–917. http://dx.doi.org/10.1515/zna-1992-7-815.

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Abstract The 79,81Br and 127I NQR spectra of several hydrobromides, respectively hydroiodides, of amino acides and dipeptides were studied, mostly as functions of temperature in the range 77 < T/K <420. The investigated compounds are: L-Arg • HBr • H2O, L-Cys • HBr • H2O , L - Cys - S - S - L - Cys • 2HBr, ethanolamine • HBr, L-Glu • HBr, L-His • HBr, L-His • 2HBr, L-Ile HBr • H2O , Sar • HBr, (Sar)2 • HBr, L-Val • HBr • H2O , Gly • LiBr, Gly-Gly • LiBr, ethanolamine HI, Sar • HI, (Sar)2 • HI, (Gly)2 • HI, (L-Val)2 • HI, Gly-L-Leu • HI • H2O . A phase transition with hysteresis was observed for L-Val • HBr • H2O (Tc.up = 318 K, Tc.down = 242 K). Two solid phases of Sar • HI have been studied by NQR, one crystallized from melt, the other one from aqueous solution. For three of the title compounds the crystal structure was determined at room temperature: L-His - 2HBr, P212121 , Z = 4, aj pm = 1652, b/pm = 916, c/pm = 721; L-Cys HBr H2O , P212121 , Z = 4, a/pm = 1955, b/pm = 746, c/pm = 550; Gly-L-Leu • HI • H2O , P2X, Z = 2, a / p m = 1289, b/pm = 914, c/pm = 615, ß/° = 99.In most cases the halogen ion in the studied hydrohalides is polycoordinated by hydrogen bonds of the type N - H • • • X⊖ and O - H • • • X⊖ , X = Br, I. The NQR frequencies and, for iodine, the nuclear quadrupole coupling constants depend on this coordination. A low frequency (coupling constant) region is found for pure N - H • • • X⊖ coordination. Replacing one N - H • • • X⊖ bond by O - H • • • X⊖ rises the electric field gradient, EFG, respectively the resonance frequencies. The dependence of the EFG on the hydrogen bond coordination N - H • • • X⊖ plus O - H • • • X⊖ is discussed for the title compounds including information from literature

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Esiegwu, A. C. "Growth performance, haematological and serum biochemical indices of finisher broiler chickens offered nutritional supplement of fluted pumpkin (Telfairia occidentalis) leaves extract." Nigerian Journal of Animal Production 48, no. 5 (November 10, 2021): 245–56. http://dx.doi.org/10.51791/njap.v48i5.3208.

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It is obvious that farmers cannot raise chicken without supplementary nutrients in the form of vitamins, minerals and amino acids provided either as anti-stress, immune booster or for growth and high productivity. The high cost of these conventional supplementary nutrients is becoming very alarming leading to high cost of production and consequently high cost of poultry products. Whereas, leaves of most plants in our agroecological zone contain these nutrients and can be obtained at no cost, it is necessary to utilize them for similar purposes to reduce cost and enhance the wellbeing of the animals. Moreso, the use of these plant leaves as juice extract will enhance absorption and utilization of the nutrients and enzymes contained therein. An experiment was conducted to determine the effect of supplementary fluted pumpkin (Telfairia occidentalis) leaves extract on the performance, haematological and serum biochemical indices of finisher broiler chickens. 200g of fluted pumpkin (Telfairia occidentalis) leaves were plucked and crushed. One litre of H2 O was used to squeeze the 2 extract (juice) from the 200g leaf. The leaf extract was further mixed (diluted) in clean drinking water at the rate of 0ml/litre of H2 O, 100ml /litre of H 2O, 200ml/litre of H20 300ml/litre of H2 O designated as T , T , T , T . In T The chickens were given conventional 2 1 3 4 5 2. supplement (vitalyte). Five groups of 30 broiler chicks (28 days old) of agritech breed were randomly assigned to one of the supplementary fluted pumpkin (Telfairia occidentalis) leaves extract and the conventional supplement for 28 days in a completely randomized design. Each group was subdivided into three replicates of 10 birds each. The birds were fed normal broiler chicken finisher diet for all the groups. At the end of the 28 days dietary trial, results showed that average body weight changes and average daily body gains were significantly increased (P < 0.05) at T (200ml/litre of H 2O). Feed conversion ratio was significantly decreased (P< 0.05) at T (200ml/litre of H2 O) compared to T and T but similar to T and T . 4 2 1 5 2 3 T also showed high degree of cost effectiveness. Haematological indices (Haemoglobin 4 Packed cell volume, Red blood cell, White blood cell etc) did not show any significant treatment (P > 0.05) effects. Biochemical indices (such as total serum protein, urea, creatinine, liver enzyme, cholesterol etc) did not vary significantly (P > 0.05). It was concluded that the inclusion of Telfairia occidentalis leaf extract as an alternative supplement to costly conventional supplements should be administered orally at 200ml/litre of H 2O due to heavier body weight gain and cost effectiveness. Il est évident que les agriculteurs ne peuvent pas élever de poulet sans nutriments supplémentaires sous forme de vitamines, de minéraux et d'acides aminés fournis soit commeanti-stress, soit comme stimulant immunitaire, soit pour la croissance et une productivité élevée. Le coût élevé de ces nutriments supplémentaires conventionnels devient très alarmant, ce qui entraîne des coûts de production élevés et par conséquent des coûts élevés des produits avicoles. Alors que les feuilles de la plupart des plantes de notre zone agro écologique contiennent ces nutriments et peuvent être obtenues gratuitement, il est nécessaire de les utiliser à des fins similaires pour réduire les coûts et améliorer le bien-être des animaux. De plus, l'utilisation de ces feuilles de plantes comme extrait de jus améliorera l'absorption et l'utilisation des nutriments et des enzymes qu'elles contiennent. Une expérience a été menée pour déterminer l'effet d'un extrait supplémentaire de feuilles de citrouille cannelée (Telfairia occidentalis) sur les performances, les indices hématologiques et biochimiques sériques des poulets de chair en finition. 200g de feuilles de courge cannelée (Telfairia occidentalis) ont été cueillies et écrasées. Un litre d'H2O a été utilisé pour presser l'extrait (jus) de la feuille de 200g. L'extrait de feuille a été ensuite mélangé (dilué) dans de l'eau potable à raison de 0 ml/litre de H2O, 100 ml/litre de H2O, 200 ml/litre de H2O et 300 ml/litre de H2O désignés comme T1, T3, T4, T5. Au T2. Les poulets ont reçu un supplément conventionnel (vitalyte). Cinq groupes de 30 poussins de chair (28 jours) de race agritech ont été assignés au hasard à l'un des extraits de feuilles de citrouille cannelées supplémentaires (Telfairia occidentalis) et au supplément conventionnel pendant 28 jours dans un design complètement randomisé. Chaque groupe a été subdivisé en trois répétitions de 10 oiseaux chacune. Les oiseaux ont été nourris avec un régime alimentaire de finition de poulet à griller normal pour tous les groupes. À la fin de l'essai diététique de 28 jours, les résultats ont montré que les changements de poids corporel moyen et les gains corporels quotidiens moyens étaient significativement augmentés (P < 0,05) à T4 (200 ml/litre de H2O). Le taux de conversion alimentaire était significativement diminué (P< 0,05) à T4 (200 ml/litre de H2O) par rapport à T1 et T5 mais similaire à T2 et T3. Le T4 a également montré un haut degré de rentabilité. Les indices hématologiques (volume globulaire d'hémoglobine, globules rouges, globules blancs, etc.) n'ont montré aucun effet significatif du traitement (P > 0,05). Les indices biochimiques (tels que les protéines sériques totales, l'urée, la créatinine, les enzymes hépatiques, le cholestérol, etc.) n'ont pas varié de manière significative (P > 0,05). Il a été conclu que l'inclusion de l'extrait de feuille de Telfairia occidentalis comme supplément alternatif aux suppléments conventionnels coûteux devrait être administrée par voie orale à 200 ml/litre de H2O en raison d'un gain de poids corporel plus important et d'un rapport coût-efficacité plus élevé.

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Fervenza, F. C., C. M. Harvey, B. M. Hendry, and J. C. Ellory. "Increased lysine transport capacity in erythrocytes from patients with chronic renal failure." Clinical Science 76, no. 4 (April 1, 1989): 419–22. http://dx.doi.org/10.1042/cs0760419.

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1. The initial rate of l-lysine influx into erythrocytes from 13 patients with chronic renal failure has been measured using 14C-labelled lysine. Ten patients were on maintenance haemodialysis and three had never been dialysed. The results are compared with data obtained from 12 normal individuals. 2. The rate of lysine influx into washed cells from buffered saline containing 0.02–0.5 mmol of l-lysine/l has been calculated. The results can be fitted with a model in which influx has a single saturable component obeying Michaelis–Menten kinetics, and a linear non-saturable component. 3. In uraemic erythrocytes the saturable component had a mean Vmax. of 0.762 mmol h−1 litre−1 of cells (n = 13, sem 0.072) and a mean Km of 68.2 μmol/l (sem 5.7). These values in normal erythrocytes were 0.566 mmol h−1 litre−1 of cells (n = 12, sem 0.033) and 70.5 μmol/l (sem 4.1), respectively. The mean apparent diffusion constant (KD) for the linear component of influx was 0.224 h−1 (sem 0.039) in uraemic cells and 0.178 h−1 (sem 0.028) in normals. 4. The 35% increase in mean Vmax. seen in uraemic erythrocytes was statistically significant (P = 0.02). A similar increase in Vmax. in uraemic cells compared with controls was seen in erythrocytes which were studied in zero-trans conditions after depletion of intracellular amino acids. The mean values of Km and KD were not significantly different in uraemia. The origins of this increased membrane transport capacity for lysine in uraemia are discussed.

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32

Marangos, C., L. Ramos, and M. Oliva. "Variations des teneurs en acides aminés libres de l'ovaire, de l'hépatopancréas et de l'hémolymphe dePenaeus schmittiau cours de la maturation ovarienne (Crustacea, Decapoda, Penaeidae)." Archives Internationales de Physiologie et de Biochimie 97, no. 1 (January 1989): 95–106. http://dx.doi.org/10.3109/13813458909075053.

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33

Labbé, Normand, Serge Parent, and Richard Villemur. "Nitratireductor aquibiodomus gen. nov., sp. nov., a novel α-proteobacterium from the marine denitrification system of the Montreal Biodome (Canada)." International Journal of Systematic and Evolutionary Microbiology 54, no. 1 (January 1, 2004): 269–73. http://dx.doi.org/10.1099/ijs.0.02793-0.

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The Montreal Biodome operates a methanol-fed denitrification system that treats the water in its three million litre marine mesocosm. An unknown bacterium, named strain NL21T, was isolated from this system on TSA and R2A agar. The organism is a Gram-negative, rod-shaped (1×3 μm) facultative aerobe. Optimal growth conditions on R2A agar are 30–35 °C, pH 7–7·5 and 1 % (w/w) NaCl. Phylogenetic analysis of the 16S rDNA sequence reveals that strain NL21T forms a novel lineage in the family ‘Phyllobacteriaceae’ within the α2 subgroup of the Proteobacteria. The closest related genera are Aminobacter, Pseudaminobacter, Mesorhizobium and Defluvibacter. Major cellular fatty acids are C18 : 1 ω7c (75 %), C19 : 0 ω8c cyclopropane (9·4 %) and C18 : 0 (4·2 %). The DNA G+C content of strain NL21T (57 mol%) differs from those of all other described members of the ‘Phyllobacteriaceae’ (60–64 mol%). Strain NL21T reduces nitrate to nitrite, but does not reduce nitrite to nitrogen gas. Only a few sugars and amino acids can serve as carbon sources. Strain NL21T is able to grow without salt and tolerates up to 5 % NaCl. Phylogenetic analysis, as well as physiological and biochemical tests, showed that strain NL21T was different from all other members of the ‘Phyllobacteriaceae’ with validly published names. Strain NL21T therefore represents a novel genus, for which the name Nitratireductor aquibiodomus gen. nov., sp. nov. is proposed, with the type strain NL21T (=DSM 15645T=ATCC BAA-762T).

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Vahidinasab, Maliheh, Isabel Adiek, Behnoush Hosseini, Stephen Olusanmi Akintayo, Bahar Abrishamchi, Jens Pfannstiel, Marius Henkel, Lars Lilge, Ralf T. Voegele, and Rudolf Hausmann. "Characterization of Bacillus velezensis UTB96, Demonstrating Improved Lipopeptide Production Compared to the Strain B. velezensis FZB42." Microorganisms 10, no. 11 (November 10, 2022): 2225. http://dx.doi.org/10.3390/microorganisms10112225.

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Bacillus strains can produce various lipopeptides, known for their antifungal properties. This makes them attractive metabolites for applications in agriculture. Therefore, identification of productive wild-type strains is essential for the development of biopesticides. Bacillus velezensis FZB42 is a well-established strain for biocontrol of plant pathogens in agriculture. Here, we characterized an alternative strain, B. velezensis UTB96, that can produce higher amounts of all three major lipopeptide families, namely surfactin, fengycin, and iturin. UTB96 produces iturin A. Furthermore, UTB96 showed superior antifungal activity towards the soybean fungal pathogen Diaporthe longicolla compared to FZB42. Moreover, the additional provision of different amino acids for lipopeptide production in UTB96 was investigated. Lysine and alanine had stimulatory effects on the production of all three lipopeptide families, while supplementation of leucine, valine and isoleucine decreased the lipopeptide bioproduction. Using a 45-litre bioreactor system for upscaling in batch culture, lipopeptide titers of about 140 mg/L surfactin, 620 mg/L iturin A, and 45 mg/L fengycin were achieved. In conclusion, it becomes clear that B. velezensis UTB96 is a promising strain for further research application in the field of agricultural biological controls of fungal diseases.

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Tulli, Francesca, Maria Messina, Matteo Calligaris, and Emilio Tibaldi. "Response of European sea bass (Dicentrarchus labrax) to graded levels of methionine (total sulfur amino acids) in soya protein-based semi-purified diets." British Journal of Nutrition 104, no. 5 (April 26, 2010): 664–73. http://dx.doi.org/10.1017/s0007114510001029.

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The dietary methionine (Met) and total sulfur amino acid (TSAA) requirements of European sea bass (Dicentrarchus labrax) (initial body weight 13·4 (sd 0·2) g) were estimated in a 12-week dose–response experiment. Seven isonitrogenous (7·6 % DM) and isoenergetic (gross energy, 21·2 MJ/kg DM) diets, based on soya protein and crystalline l-amino acids containing graded levels of l-Met (1·6–16·2 g/kg) at a constant cysteine (4 g/kg) level and a fish meal-based diet, were fed each to triplicate groups of fifty fish kept in 250 litre tanks in a thermoregulated (23 ± 0·5°C) seawater system. The Met and TSAA-deficient diet resulted in higher mortality, impaired feed intake and growth relative to the other treatments (P < 0·01). No signs of lens opacity due to limiting Met intake were observed and no feed intake or growth depression occurred at the highest level of dietary TSAA. Met and TSAA requirements for optimal N deposition or weight gain as fitted with the broken-line model resulted in estimated values of 8·0 and 12·0 g/kg diet (for example, 1·8 and 2·7 % dietary protein) and 9·1 and 13·1 g/kg diet (for example, 2·0 and 3·0 % dietary protein), respectively. Plasma levels of Met, homocysteine and cysteine increased in response to excess dietary TSAA, corroborating requirement estimates from growth data. N gain resulted in a linear function of TSAA consumption at marginal Met (TSAA) intake. The TSAA intake needed to maintain N balance resulted in a value of 20·0 mg TSAA/kg average body weight0·75 per d, which represents 23 % of the total (maintenance+accretion) requirement.

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PATUREAU-MIRAND, P., O. BERNARD, J. PRUGNAUD, D. LEVIEUX, R. PION, G. BAYLE, F. BARRE, et al. "Métabolisme protéique de l'agneau nouveau-né. — I. Conséquences de l'ingestion de colostrum sur la glycémie, la gammaglobulinémie et les teneurs en acides aminés libres des tissus." Reproduction Nutrition Développement 25, no. 6 (1985): 1047–60. http://dx.doi.org/10.1051/rnd:19850805.

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37

Lallès, JP, C. Poncet, R. Toullec, M. Formal, and E. Delval. "Composition en acides aminés des bactéries libres et des bactéries fixées aux particules alimentaires du réticulo-rumen du veau sevré et du mouton recevant différentes rations." CrossRef Listing Of Deleted DOIs 41, no. 1 (1992): 75–76. http://dx.doi.org/10.1051/rnd:19920138.

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Lallès, JP, C. Poncet, R. Toullec, M. Formal, and E. Delval. "Composition en acides aminés des bactéries libres et des bactéries fixées aux particules alimentaires du réticulo-rumen du veau sevré et du mouton recevant différentes rations." Annales de Zootechnie 41, no. 1 (1992): 75–76. http://dx.doi.org/10.1051/animres:19920138.

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39

Díaz-Rizzolo, Diana A., Nihan Acar-Denizli, Belchin Kostov, Elena Roura, Antoni Sisó-Almirall, Pedro Delicado, and Ramon Gomis. "Glycaemia Fluctuations Improvement in Old-Age Prediabetic Subjects Consuming a Quinoa-Based Diet: A Pilot Study." Nutrients 14, no. 11 (June 1, 2022): 2331. http://dx.doi.org/10.3390/nu14112331.

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This study aimed to observe if quinoa could produce a benefit on postprandial glycemia that would result in less progression to type 2 diabetes (T2D). A cross-over design pilot clinical study with a nutritional intervention for 8 weeks was performed: 4 weeks on a regular diet (RD) and 4 weeks on a quinoa diet (QD). Nine subjects aged ≥65 years with prediabetes were monitored during the first 4 weeks of RD with daily dietary records and FreeStyle Libre®. Subsequently, participants started the QD, where quinoa and 100% quinoa-based products replaced foods rich in complex carbohydrates that they had consumed in the first 4 weeks of RD. The glycemic measurements recorded by the sensors were considered as functions of time, and the effects of nutrients consumed at the intended time period were analyzed by means of a function-on-scalar regression (fosr) model. With QD participants, decreased body weight (−1.6 kg, p = 0.008), BMI (−0.6 kg/m2p = 0.004) and waist circumference (−1.5 cm, p = 0.015) were observed. Nutrients intake changed during QD, namely, decreased carbohydrates (p = 0.004) and increased lipids (p = 0.004) and some amino acids (p < 0.05). The fosr model showed a reduction in postprandial glycemia in QD despite intrapersonal differences thanks to the joint action of different nutrients and the suppression of others consumed on a regular diet. We conclude that in an old age and high T2D-risk population, a diet rich in quinoa reduces postprandial glycemia and could be a promising T2D-preventive strategy.

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Bisht, Saraswati. "Growth responses of aquatic hyphomycetes to different sources of carbon and nitrogen." Journal of Applied and Natural Science 5, no. 2 (December 1, 2013): 313–17. http://dx.doi.org/10.31018/jans.v5i2.323.

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Assessment of different sources of carbon and nitrogen in terms of dry weight biomass of four selected aquatic hyphomycetes viz; Flagellospora penicilloides Ingold, Pestalotiopsis submersus Sati and Tiwari, Tetrachaetum elegans Ingold and Tetracladium marchalianum De Wildeman was made for their nutritional requirements. Eight carbon sources and ten nitrogen sources were singly added to the basal media in order to provide 4g of carbon and 1g of nitrogen per litre of distilled water. Among carbon compounds glucose and sucrose were found to be most suitable sources of carbon for all the four fungal isolates, where as fructose proved good for T. marchalianum, P. submersus and F.penicilloides fairly. Cellulose was found a poor source of carbon for the growth of all these isolates. The inorganic sources of nitrogen were found as good nitrogen sources with preference for ammonium ions. Suitability of amino acids was found variable from species to species for nitrogen. T.elegans and T.marchalianum had their maximum growth in asparagines, whereas, P. submersus had their highest growth in proline. Cysteine was observed as a good source of nitrogen for almost all the fungal isolates used. Anova calculated for these observed data showed significant variations in the dry weight production of different fungal species grown in different sources of carbon and nitrogen(P<0.01).

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Pavillon, Jean-François, and Pascale Rault. "Variations mensuelles des acides aminés libres dissous (AALD) présents en un point de la rade de Villefranche-sur-Mer : utilisation par les larves deParacentrotus lividuset deSphaerechinus granularis." Aquatic Living Resources 3, no. 2 (April 1990): 147–50. http://dx.doi.org/10.1051/alr:1990015.

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42

Marsot, P. "Activités métaboliques et toxicité du dinoflagellé Alexandrium tamarense en culture à dialyse exposée à un milieu estuarien." Canadian Journal of Microbiology 43, no. 4 (April 1, 1997): 305–14. http://dx.doi.org/10.1139/m97-043.

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Metabolic activities and toxicity of the dinoflagellate Alexandrium tamarense were studied for a dialysis culture exposed to unenriched natural seawater and a batch culture grown in an enriched medium. The following observations were made on the dialysis culture compared with the batch culture: (i) Depending on the season period, the cell densities per litre were similar (≈ 10 × 106 – 14 × 106) or greater (66 × 106). (ii) During growth and stationary phases, cellular consumption of the nutrients (NO3− + NO2−) was much greater (5–50 times), (iii) During growth, the composition of the intracellular (IFAA) and extracellular dissolved free amino acid (EFAA) was characterized by the presence of ORN and LYS in the dialysis culture, which represent a substantial fraction of the IFAA pool of the dinoflagellate; a significant depletion of the IFAA was observed, but the recovery of Gln, Glu, and Arg cell concentration levels at the stationary phase was more important. (iv) During the growth phase, the maximum excretion rate of amino acids (fmol∙cell−1∙d−1) was 263 (in decreasing order of importance: Glu, Gin, Ser, Asp, Leu, Ala, G+T, and Orn) compared with 14,5. (v) During stationary phase, the reduction in excretion activity was twofold with Gln, Glu, Leu, and Orn while 9,2 fmol∙cell−1∙d−1 were observed in batch culture, (vi) Total toxin content was about 4 to 5 times higher (means: 95 and 75 fmol∙cell−1 during growth and stationary phases respectively), with greater concentrations in more potent derivates like saxitoxin and neosaxitoxin. This higher cell toxicity may be attributed to the particular growth conditions of the dialysis culture, which more closely approximate the natural environment, through diffusion processes involving a constant elimination of low molecular weight autoinhibitory metabolites and a more efficient nutrient uptake.Key words: Alexandrium tamarense, dinoflagellate, dialysis culture, phycotoxins, nitrogen metabolism.

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Marangos, Christakis, Abderrafie Guissi, and Hubert J. Ceccaldi. "Variations de la teneur en acides aminés libres et de l'excrétion ammoniacale chez les post-larves de Penaeus japonicus en fonction de la salinité et des chocs osmotiques." Biochemical Systematics and Ecology 17, no. 1 (March 1989): 59–67. http://dx.doi.org/10.1016/0305-1978(89)90044-6.

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Tonacchera, Massimo, Filomena Cetani, Sabine Costagliola, Laura Alcalde, Raivo Uibo, Gilbert Vassart, and Marian Ludgate. "Mapping thyroid peroxidase epitopes using recombinant protein fragments." European Journal of Endocrinology 132, no. 1 (January 1995): 53–61. http://dx.doi.org/10.1530/eje.0.1320053.

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Tonacchera M, Cetani F, Costagliola S, Alcalde L, Uibo R, Vassart G, Ludgate M, Mapping thyroid peroxidase epitopes using recombinant protein fragments. Eur J Endocrinol 1995,132:53-61. ISSN 0804–4643 The identification of autoantibody epitopes is important to the understanding of autoimmune thyroid diseases. In the case of thyroid peroxidase antibodies (TPO-ab), recent reports have disagreed about the number and type of autoantibody epitopes found in human TPO. In order to clarify the nature of these epitopes, we used an approach that provides recombinant human TPO produced by bacterial cells. The cDNA of four slightly overlapping fragments of human TPO—TPO 1(Glu 17–Ser 227), TPO 2(Tyr 226–Thr 476), TPO 3(Glu 471–Ser 720) and TPO 4(Phe 709–Leu 993)—were amplified by polymerase chain reaction and subcloned into the expression vector pMAL. In addition, a TPO 3 species for an alternatively spliced form of TPO of 876 amino acids was constructed (TPO 3M). Each of these constructs encodes a fusion protein, in which the amino terminal portion is maltose-binding protein, followed by the sequence of the fragment of human TPO. The plasmid constructs were transformed in Escherichia coli and, after growth, bacterial cells were harvested, lysed and the lysate was passed over an amylose affinity column and eluted with maltose. Western blots were performed using 33 sera from patients with autoimmune thyroid disease (group 1) and 17 sera from patients with nodular goiter and focal thyroiditis (group 2), all positive for TPO-ab measured by radioimmunoassay; sera from 10 healthy people with no clinical evidence of thyroiditis and positive for TPO-ab measured by radioimmunoassay (group 3) and sera from 30 patients with antigastric parietal cell antibodies without signs or symptoms of thyroiditis, 16 negative for TPO-ab (group 4a) and 14 positive for TPO-ab (group 4b), were included in the study. The four TPO fragments and the alternatively spliced form of TPO were used as antigens. Our results show that in the first group 91% of sera recognized TPO 3, 33% recognized TPO 4 while 21% and 18% reacted with TPO 1 and TPO 2, respectively. In the second group of patients 76% of sera recognized TPO 3, 35% recognized TPO 4, 29% reacted with TPO 1 and 29% with TPO 2. In group 3 (normal healthy people) the individual peptides were recognized at a similar frequency compared to the other groups. In group 4a, 75% and in group 4b, 93% of sera reacted with one of the fusion recombinant proteins. Immunoreactivity with TPO 3M was the same as that of TPO 3. In conclusion: (i) we have optimized the production of TPO peptides in bacterial cells; (ii) TPO-ab are able to bind many amino acid sequences of the protein with a hot spot in TPO 3 (known to contain the linear epitopes C2(590–622) and C21(709–721); (iii) TPO-ab recognize other epitopes in the amino and carboxyl portions of the protein; (iv) no difference is observed when comparing the levels of antibodies and the number or type of peptide fragments recognized; (v) there are no disease-specific epitopes, as sera from normal healthy subjects with TPO-ab recognize the same epitopes in a similar percentage to those recognized by patients; (vi) the immunoreactivity of TPO 3 is not changed when the fragment expressed is the alternatively spliced form; (vii) we confirm that antigastric parietal cell antibodies recognize epitopes on the TPO molecule even when TPO-ab are negative by radioimmunoassay, suggesting a shared epitope between TPO and the gastric parietal cell. Massimo Tonacchera, Institut de Recherche Interdisciplinaire, Université Libre de Bruxelles, Campus Erasme, 808 Route de Lennik, 1070 Bruxelles, Belgium

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Lima Rocha, Maria Eunice, Diana Jhulia Palheta de Sousa, Jessica Suellen Silva Teixeira, Marlene De Matos Malavasi, Cândido Ferreira de Oliveira Neto, and Ubirajara Contro Malavasi. "Biochemical Modifications in Seedlings of Cedar Submitted to Salicylic Acid Application." Ensaios e Ciência C Biológicas Agrárias e da Saúde 25, no. 5-esp. (March 14, 2022): 551–57. http://dx.doi.org/10.17921/1415-6938.2021v25n5-esp.p551-557.

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The factors that limit forest production the most are abiotic stresses; soon, when plants are exposed to these conditions there will be secondary metabolites production and the exogenous application of growth regulators can facilitate and accelerate some adaptive responses. Therefore, the research aimed to evaluate biochemical changes associated with nitrogen metabolism in C.fissilis seedlings submitted to water deficit with salicylic acid (SA) application. The experiment used 400 seedlings of C.fissilis and the experimental design used in the phase prior to the water deficit imposition was completely randomized and composed of 4 doses of SA (0; 100; 200 and 300 mg L-1) with 5 repetitions of 20 seedlings each. SA application was performed weekly for 2 months. At the end of that period, seedlings from each treatment (doses of SA) were randomly selected and submitted to water deficit for 4, 8 and 12 days. The biochemical analyzes performed consisted of relative content of water (RCW), nitrate, free ammonium, total soluble amino acids, proline and glycine-betaine. The dose of 300 mg L-1 of SA was considered extremely high because it resulted in a great alteration in seedling metabolism. On the other hand, for most parameters, the dose of 100 mg L-1 was efficient in signaling RCW as it reduced water loss and consequently kept seedlings alive longer. Keywords: Analyzes. Nitrate. Nitrogen Metabolism. Water Deficit. Resumo Os fatores que mais limitam a produção florestal são os estresses abióticos, logo, quando as plantas são expostas a essas condições podem sofrer muitas modificações, assim, muitos estudos têm destacado respostas pertinentes com a aplicação exógena de reguladores e alteração metabólica que pode resultar em respostas adaptativa nas plantas. Portanto, a pesquisa teve como objetivo avaliar alterações bioquímicas ligadas ao metabolismo do nitrogênio em mudas de C.fissilis submetidas a déficit hídrico e com aplicação de ácido salicílico (AS). O experimento utilizou 400 mudas de C.fissilis e o delineamento experimental utilizado na fase anterior à imposição de déficit hídrico foi o inteiramente casualizado, composto por 4 doses de AS (0, 100, 200 e 300 mg L-1), com 5 repetições de 20 mudas cada. A aplicação do AS foi realizada semanalmente por 2 meses. Ao final desse período, mudas de cada tratamento (doses de AS) foram selecionadas aleatoriamente e submetidas a déficit hídrico por 4, 8 e 12 dias. As análises bioquímicas realizadas consistiram no conteúdo relativo de água (CRA), nitrato, amônio livre, aminoácidos solúveis totais, prolina e glicina-betaína. A dose de 300 mg L-1 de AS pode ser considerada muito alta, pois resultou em uma grande alteração no metabolismo das mudas. Por outro lado, para a maioria dos parâmetros, a dose de 100 mg L-1 foi eficiente em sinalizar à condição de déficit hídrico e com isso mantendo o CRA por meio da redução da perda de água e consequentemente mantendo as mudas vivas por mais tempo. Palavras-chave: Análises. Nitrato. Metabolismo do Nitrogênio. Déficit Hídrico

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Gomes do Ó, Laís Monique, Alide Mitsue Watanabe Cova, Petterson Costa Conceição Silva, Hans Raj Gheyi, André Dias de Azevedo Neto, and Rogério Ferreira Ribas. "ASPECTOS BIOQUÍMICOS E FLUORESCÊNCIA DA CLOROFILA A EM PLANTAS DE MINIMELANCIA HIDROPÔNICA SOB ESTRESSE SALINO*." IRRIGA 26, no. 2 (June 30, 2021): 221–39. http://dx.doi.org/10.15809/irriga.2021v26n2p221-239.

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ASPECTOS BIOQUÍMICOS E FLUORESCÊNCIA DA CLOROFILA A EM PLANTAS DE MINIMELANCIA HIDROPÔNICA SOB ESTRESSE SALINO* LAÍS MONIQUE GOMES DO Ó1, ALIDE MITSUE WATANABE COVA2, PETTERSON COSTA CONCEIÇÃO SILVA3, HANS RAJ GHEYI4, ANDRÉ DIAS DE AZEVEDO NETO5, ROGÉRIO FERREIRA RIBAS6 1Doutoranda em Engenharia Agrícola da Universidade Federal do Recôncavo da Bahia, Rua Rui Barbosa, s/n, Cruz das Almas, Bahia, Brasil laisnique@hotmail.com. 2Pós-Doutoranda no Programa de Pós-graduação de Engenharia Agrícola da Universidade Federal do Recôncavo da Bahia, Rua Rui Barbosa, s/n, Cruz das Almas, Bahia, Brasil, alidewatanabe@yahoo.com.br. 3Doutor em Engenharia Agrícola, Universidade Federal do Recôncavo da Bahia, Rua Rui Barbosa, s/n, Cruz das Almas, Bahia, Brasil, petter.ufrb@gmail.com. 4Professor Visitante, Universidade Federal do Recôncavo da Bahia, Cruz das Almas, Bahia, hgheyi@gmail.com. 5Professor Universidade Federal do Recôncavo da Bahia, Rua Rui Barbosa, s/n, Cruz das Almas, Bahia, Brasil, andre@ufrb.edu.br. 6Professor Universidade Federal do Recôncavo da Bahia, Rua Rui Barbosa, s/n, Cruz das Almas, Bahia, Brasil, ecofisiologia@gmail.com. *Este artigo é proveniente da tese de doutorado do primeiro autor. 1 RESUMO A salinidade é um dos principais estresses abióticos que induz distúrbios bioquímicos e fisiológicos em diversas culturas. O objetivo do trabalho foi investigar os efeitos da salinidade da solução nutritiva (CEsol) sobre a produção, acúmulo de solutos orgânicos e inorgânicos e fluorescência da clorofila a em plantas de minimelancia cv. Sugar Baby. O delineamento experimental foi o inteiramente casualizado com quatro repetições. As plantas foram cultivadas em sistema hidropônico com cinco níveis de CEsol: 2,5; 3,5; 4,5; 5,5 e 6,5 dS m-1. Foram avaliados: massa do fruto, biomassa da parte aérea, teores de clorofilas a e b, fluorescência da clorofila a e teores de solutos orgânicos e inorgânicos. A massa do fruto e a biomassa seca da parte aérea foram influenciadas negativamente pela CEsol. Houve redução na concentração de carboidratos solúveis totais, aminoácidos livres, proteínas solúveis e prolina livre com o aumento da CEsol. Os íons sódio, cloreto e razão sódio/potássio aumentaram com a salinidade e os teores de potássio foram reduzidos. O incremento da salinidade aumentou linearmente o teor de clorofila b e reduziu linearmente o rendimento quântico da conversão de energia fotoquímica do FSII promovendo um ligeiro aumento no rendimento quântico da perda de energia regulada do FSII. Palavras-chaves: biomassa, carboidratos, íons tóxicos, estresse abiótico. Ó, L. M. G.; COVA, A. M. W.; SILVA, P. C. C.; GHEYI, H. R.; AZEVEDO NETO, A. D. de; RIBAS, R. F. BIOCHEMICAL ASPECTS AND CHLOROPHYLL A FLUORESCENCE IN HYDROPONIC MINI WATERMELON PLANTS UNDER SALT STRESS 2 ABSTRACT Salinity is one of the main abiotic stresses that induce biochemical and physiological disorders in diverse crops. This study investigated the effects of nutrient solution salinity (ECsol) on production, accumulation of organic and inorganic solutes and chlorophyl a fluorescence in mini watermelon plants cv. Sugar Baby. The experimental design was completely randomized with four replications. The plants were grown in a hydroponic system with five levels of ECsol: 2.5; 3.5; 4.5; 5.5 and 6.5 dS m-1. The variables evaluated were the mass of the fruit, the biomass of the aerial parts, contents of chlorophylls a and b, fluorescence of chlorophyll a, and contents of organic and inorganic solutes. The mass of the fruit and dry biomass of the aerial parts was negatively influenced by ECsol. There was a reduction in the concentration of total soluble carbohydrates, free amino acids, soluble proteins and free proline with the increase in ECsol. The sodium, chloride and sodium/potassium ratio increased with ECsol and potassium levels were reduced. The increase in ECsol linearly increased the chlorophyll b content and reduced the quantum yield of the photochemical energy conversion of the PSII promoting a slight increase in the quantum yield of the regulated energy loss of the PSII. Keywords: abiotic stress, biomass, carbohydrates, toxic ions.

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Kantwa, Suresh Chand, Upesh Kumar, and S. J. Patel. "Azolla as a Green Fodder Feed Supplent of Cross Breed Cows in District- Sehore (M.P.)." Bhartiya Krishi Anusandhan Patrika, Of (January 1, 2022). http://dx.doi.org/10.18805/bkap378.

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Background: Azolla is a floating fern also known as duck weed is belongs to the family Salviniaceae. Azolla is a good source of protein and contains almost all essential amino acids and minerals such as iron, calcium, magnesium, potassium, phosphorus, manganese etc. Methods: In the present dairy business, the cost of milk production is increasing due to market based feed management and lack of green fodder. In the context of which, Krishi Vigyan Kendra, District- Sehore (M.P.) were conducted 20 no of trais in the field of farmers during 2014-15 and 2015-16. KVK, Sehore assessed the technology is Dry fodder 4 Kg/ Day/ Animal + Green Fodder @ 20 Kg/ Day/ Animal + 2 Kg Concentrate feed/Day/Animal for body maintenance alongwith additional 1 Kg Concentrate feed/Day/Animal in every 3 litre Milk yield + 50 gm mineral mixture/ Day/ Animal. Result: Under the assessed technology, farmers found 12.5 per cent milk enhancement in assessed technology 2 as compared to farmers practice (Assessed technology-1) and 26.04 per cent higher milk yield in assessed technology 3 as compared to farmers practice (Assessed technology-1) likewise 4.76 per cent enhance the fat per cent in assessed technology 2 as compared to farmers practice (Assessed technology-1) and 9.24 per cent enhance the fat per cent in assessed technology 3 as compared to farmers practice (Assessed technology-1).

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Journal articles on the topic 'Acide aminé libre'

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