Ionophores
Mostrando 13-24 de 221 artigos, teses e dissertações.
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13. Suplementação com ionóforo à dieta de novilhas leiteiras em crescimento compensatório / Ionophore supplementation in the diet of dairy heifers in compensatory growth
The objective proposed for this study was to evaluate the compensatory growth regimes and the supplementation with ionophores to the diet on the performance, digestive parameters, metabolic profile and mammary gland development of dairy heifers. The experiment was carried out during the period of April to September of 2004. Twenty purebred heifers from the B
Publicado em: 2005
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14. Desempenho de bovinos confinados suplementados com diferentes ionóforos / Performance of beef cattle in feedlot supplemented with different ionophores
O presente trabalho teve como objetivo a avaliação do desempenho de 36 bovinos castrados Nelore confinados durante 100 dias de experimentação. Os tratamentos foram: controle (sem ionóforo), 44 mg de lasalocida/kg de (MS) matéria seca de concentrado e 44 mg de monensina/kg de MS de concentrado. Como fonte de volumoso, foi utilizado feno de Coast-Cross (
Publicado em: 2004
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15. Paired moving charge model of energy coupling. III. Intrinsic ionophores in energy coupling systems.
The experimental basis for the postulated role of intrinsic ionophores in mitochondrial ion transport and energy coupling is summarized. Intrinsic ionophores appear to be linked to, or contained within, specific ionophoroproteins localized in the inner membrane, and the isolation of these ionophores requires their release from the ionophoroproteins. At least
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16. Bone resorption in organ culture: inhibition by the divalent cation ionophores A23187 and X-537A.
The ionophores A23187 and X-537A were used as probes to investigate the possible role of calcium uptake by bone as a mediator for the stimulation of bone resorption induced by parathyroid hormone (PTH) and other agents in cultured mouse calvaria. The ionophores alone at concentrations from 1 nM to 20 muM did not stimulate bone resorption, nor did they potent
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17. Formation of hybrid complexes between Ca2+ and the ionophores bromolasalocid (Br-X537A) and A23187
The ionophores A23187 and bromolasalocid (Br-X537A) acted synergistically in translocating Ca2+ from an aqueous into an organic immiscible phase or in mediating Ca2+ transport across the organic phase, the effects obtained in the simultaneous presence of both ionophores being greater than those expected from a summation of the individual effects of each iono
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18. Effects of potassium ion concentrations on the antimicrobial activities of ionophores against ruminal anaerobes.
The antimicrobial activities of monensin and lasalocid against representative strains of ruminal bacteria were evaluated in medium containing three different concentrations of potassium (1.3, 7.9, or 23.3 mM). The growth of Eubacterium ruminantium was inhibited by low concentrations of ionophores (less than or equal to 0.16 mg/liter), while the strain of Str
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19. Characterization of the potent in vitro and in vivo antimalarial activities of ionophore compounds.
Large-scale in vitro screening of different types of ionophores previously pinpointed nine compounds that were very active and selective in vitro against Plasmodium falciparum; their in vitro and in vivo antimalarial effects were further studied. Addition of the ionophores to synchronized P. falciparum suspensions revealed that all P. falciparum stages were
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20. Serum stimulates the Na+,K+ pump in quiescent fibroblasts by increasing Na+ entry.
Two ionophores (monensin and gramicidin) that carry Na+ into 3T3 cells markedly enhance the rate of 86Rb+ uptake. Ouabain prevents both ionophores from increasing 86Rb+ uptake, indicating that the ionophores activate the Na+,K+ pump. Measurements of 86Rb+ uptake and cell Na+ and K+ over a range of monensin concentrations show that the activity of the Na+,K+
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21. Inhibition of Cryptosporidium parvum in neonatal Hsd:(ICR)BR Swiss miceby polyether ionophores and aromatic amidines.
Cryptosporidicidal effects of two polyether ionophores (maduramicin and alborixin), a fluorinated 4-quinolone (enrofloxacin), and three analogs of pentamidine were evaluated in a suckling mouse bioassay. Treatment with all compounds except enrofloxacin and one of the pentamidine analogs [1,3-di(4-imidazolinophenoxy)propane] resulted in significant (P less th
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22. Effects of pH conditions on Ca2+ transport catalyzed by ionophores A23187, 4-BrA23187, and ionomycin suggest problems with common applications of these compounds in biological systems.
Phospholipid vesicles loaded with Quin-2 and 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF) have been used to investigate the effects of pH conditions on Ca2+ transport catalyzed by ionophores A23187, 4-BrA23187, and ionomycin. At an external pH of 7.0, a delta pH (inside basic) of 0.4-0.6 U decreases the rate of Ca2+ transport into the vesicles b
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23. Monovalent ionophores inhibit secretion of procollagen and fibronectin from cultured human fibroblasts
Procollagen and fibronectin are major products of confluent fibroblasts in culture and both are released from the cells. Procollagen is secreted by known pathways, while the mechanism of fibronectin release is controversial. We find that the secretion of both these proteins can be reduced to 20% by low concentrations (0.1-1 μM) of ionophores that have affin
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24. Ionophores stimulate prostaglandin and thromboxane biosynthesis