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[PMID]:27280286
[Au] Autor:Wray R; Iscla I; Gao Y; Li H; Wang J; Blount P
[Ad] Endereço:Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America.
[Ti] Título:Dihydrostreptomycin Directly Binds to, Modulates, and Passes through the MscL Channel Pore.
[So] Source:PLoS Biol;14(6):e1002473, 2016 Jun.
[Is] ISSN:1545-7885
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The primary mechanism of action of the antibiotic dihydrostreptomycin is binding to and modifying the function of the bacterial ribosome, thus leading to decreased and aberrant translation of proteins; however, the routes by which it enters the bacterial cell are largely unknown. The mechanosensitive channel of large conductance, MscL, is found in the vast majority of bacterial species, where it serves as an emergency release valve rescuing the cell from sudden decreases in external osmolarity. While it is known that MscL expression increases the potency of dihydrostreptomycin, it has remained unclear if this effect is due to a direct interaction. Here, we use a combination of genetic screening, MD simulations, and biochemical and mutational approaches to determine if dihydrostreptomycin directly interacts with MscL. Our data strongly suggest that dihydrostreptomycin binds to a specific site on MscL and modifies its conformation, thus allowing the passage of K+ and glutamate out of, and dihydrostreptomycin into, the cell.
[Mh] Termos MeSH primário: Sulfato de Di-Hidroestreptomicina/metabolismo
Proteínas de Escherichia coli/metabolismo
Escherichia coli/metabolismo
Canais Iônicos/metabolismo
[Mh] Termos MeSH secundário: Antibacterianos/química
Antibacterianos/metabolismo
Antibacterianos/farmacologia
Sítios de Ligação/genética
Membrana Celular/metabolismo
Cisteína/química
Cisteína/genética
Cisteína/metabolismo
Sulfato de Di-Hidroestreptomicina/química
Sulfato de Di-Hidroestreptomicina/farmacologia
Escherichia coli/efeitos dos fármacos
Escherichia coli/genética
Proteínas de Escherichia coli/química
Proteínas de Escherichia coli/genética
Ácido Glutâmico/metabolismo
Ativação do Canal Iônico
Canais Iônicos/química
Canais Iônicos/genética
Mecanorreceptores/química
Mecanorreceptores/metabolismo
Simulação de Acoplamento Molecular
Simulação de Dinâmica Molecular
Mutação
Potássio/metabolismo
Ligação Proteica
Conformação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Escherichia coli Proteins); 0 (Ion Channels); 0 (MscL protein, E coli); 3KX376GY7L (Glutamic Acid); K848JZ4886 (Cysteine); RWP5GA015D (Potassium); T7D4876IUE (Dihydrostreptomycin Sulfate)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170621
[Lr] Data última revisão:
170621
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160610
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pbio.1002473


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[PMID]:26987198
[Au] Autor:Liu T; Wang S; Ma Y; Cheng J; Shen S; Wang Z
[Ti] Título:[Determination of streptomycin and dihydrostreptomycin residues in tomato ketchup by UPLC-MS/MS].
[So] Source:Wei Sheng Yan Jiu;45(1):61-4, 2016 Jan.
[Is] ISSN:1000-8020
[Cp] País de publicação:China
[La] Idioma:chi
[Ab] Resumo:OBJECTIVE: To develop a method for simultaneous determination of streptomycin and dihydrostreptomycin residues in tomato ketchup by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). METHODS: The sample was dissolved with phosphorus solution (pH 2) and extracted by ultrasonic. The pigment was removed with n-hexane. Then, the sample was cleaned up by HLB SPE. The HILIC chromatographic column (100 mm x 2.1 mm, 1.7 µm) was used to complete the separation under gradient elution. The mixed solution of 0.1% formic acid solution and acetonitrile was used as mobile phase. The detection of streptomycin and dihydrostreptomycin were carried out by MS/MS under multiple reaction monitoring (MRM) mode. The external standard method was used for quantitative analysis. RESULTS: The calibration curves for streptomycin and dihydrostreptomycin were indicated in the range of 0.005 - 0.100 mg/kg, and the detection limits were both 0.005 mg/kg. The recoveries of streptomycin and dihydrostreptomycin were ranged from 79.5% to 93.9% with relative standard deviations no more than 10%. CONCLUSION: The method is simple and accurate to meet the requirements for determination of streptomycin and dihydrostreptomycin residues in tomato ketchup.
[Mh] Termos MeSH primário: Sulfato de Di-Hidroestreptomicina/análise
Contaminação de Alimentos/análise
Lycopersicon esculentum/química
Estreptomicina/análise
Espectrometria de Massas em Tandem/métodos
[Mh] Termos MeSH secundário: Cromatografia Líquida de Alta Pressão
Resíduos de Drogas/análise
Alimentos
Hexanos
Extração em Fase Sólida
[Pt] Tipo de publicação:ENGLISH ABSTRACT; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hexanes); 2DDG612ED8 (n-hexane); T7D4876IUE (Dihydrostreptomycin Sulfate); Y45QSO73OB (Streptomycin)
[Em] Mês de entrada:1604
[Cu] Atualização por classe:160318
[Lr] Data última revisão:
160318
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160319
[St] Status:MEDLINE


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[PMID]:26758827
[Au] Autor:Corns LF; Johnson SL; Kros CJ; Marcotti W
[Ad] Endereço:Department of Biomedical Science, University of Sheffield, Sheffield, South Yorkshire S10 2TN, United Kingdom.
[Ti] Título:Tmc1 Point Mutation Affects Ca2+ Sensitivity and Block by Dihydrostreptomycin of the Mechanoelectrical Transducer Current of Mouse Outer Hair Cells.
[So] Source:J Neurosci;36(2):336-49, 2016 Jan 13.
[Is] ISSN:1529-2401
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:UNLABELLED: The transduction of sound into electrical signals depends on mechanically sensitive ion channels in the stereociliary bundle. The molecular composition of this mechanoelectrical transducer (MET) channel is not yet known. Transmembrane channel-like protein isoforms 1 (TMC1) and 2 (TMC2) have been proposed to form part of the MET channel, although their exact roles are still unclear. Using Beethoven (Tmc1(Bth/Bth)) mice, which have an M412K point mutation in TMC1 that adds a positive charge, we found that Ca(2+) permeability and conductance of the MET channel of outer hair cells (OHCs) were reduced. Tmc1(Bth/Bth) OHCs were also less sensitive to block by the permeant MET channel blocker dihydrostreptomycin, whether applied extracellularly or intracellularly. These findings suggest that the amino acid that is mutated in Bth is situated at or near the negatively charged binding site for dihydrostreptomycin within the permeation pore of the channel. We also found that the Ca(2+) dependence of the operating range of the MET channel was altered by the M412K mutation. Depolarization did not increase the resting open probability of the MET current of Tmc1(Bth/Bth) OHCs, whereas raising the intracellular concentration of the Ca(2+) chelator BAPTA caused smaller increases in resting open probability in Bth mutant OHCs than in wild-type control cells. We propose that these observations can be explained by the reduced Ca(2+) permeability of the mutated MET channel indirectly causing the Ca(2+) sensor for adaptation, at or near the intracellular face of the MET channel, to become more sensitive to Ca(2+) influx as a compensatory mechanism. SIGNIFICANCE STATEMENT: In the auditory system, the hair cells convert sound-induced mechanical movement of the hair bundles atop these cells into electrical signals through the opening of mechanically gated ion channels at the tips of the bundles. Although the nature of these mechanoelectrical transducer (MET) channels is still unclear, recent studies implicate transmembrane channel-like protein isoform 1 (TMC1) channels in the mammalian cochlea. Using a mutant mouse model (Beethoven) for progressive hearing loss in humans (DFNA36), which harbors a point mutation in the Tmc1 gene, we show that this mutation affects the MET channel pore, reducing its Ca(2+) permeability and its affinity for the permeant blocker dihydrostreptomycin. A number of phenomena that we ascribe to Ca(2+)-dependent adaptation appear stronger, in compensation for the reduced Ca(2+) entry.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Cálcio/metabolismo
Sulfato de Di-Hidroestreptomicina/farmacologia
Células Ciliadas Auditivas Externas/efeitos dos fármacos
Mecanotransdução Celular/efeitos dos fármacos
Proteínas de Membrana/genética
Mutação Puntual/genética
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Cálcio/farmacologia
Quelantes/farmacologia
Relação Dose-Resposta a Droga
Ácido Egtázico/análogos & derivados
Ácido Egtázico/farmacologia
Células Ciliadas Auditivas Externas/fisiologia
Técnicas In Vitro
Mecanotransdução Celular/genética
Potenciais da Membrana/efeitos dos fármacos
Potenciais da Membrana/genética
Proteínas de Membrana/metabolismo
Camundongos
Camundongos Transgênicos
Fibras Nervosas/efeitos dos fármacos
Fibras Nervosas/fisiologia
Órgão Espiral/citologia
Técnicas de Patch-Clamp
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Chelating Agents); 0 (Membrane Proteins); 0 (TMC1 protein, mouse); 0 (TMC2 protein, mouse); 526U7A2651 (Egtazic Acid); K22DDW77C0 (1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid); SY7Q814VUP (Calcium); T7D4876IUE (Dihydrostreptomycin Sulfate)
[Em] Mês de entrada:1605
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160114
[St] Status:MEDLINE
[do] DOI:10.1523/JNEUROSCI.2439-15.2016


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[PMID]:26061440
[Au] Autor:Usui M; Shirakawa T; Fukuda A; Tamura Y
[Ad] Endereço:Laboratory of Food Microbiology and Food Safety, Department of Health and Environmental Sciences, School of Veterinary Medicine, Rakuno Gakuen University , Hokkaido, Japan .
[Ti] Título:The Role of Flies in Disseminating Plasmids with Antimicrobial-Resistance Genes Between Farms.
[So] Source:Microb Drug Resist;21(5):562-9, 2015 Oct.
[Is] ISSN:1931-8448
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Dissemination of antimicrobial resistance is a major global public health concern. To clarify the role of flies in disseminating antimicrobial resistance between farms, we isolated and characterized tetracycline-resistant Escherichia coli strains isolated from flies and feces of livestock from four locations housing swine (abattoir, three farms) and three cattle farms. The percentages of isolates from flies resistant to tetracycline, dihydrostreptomycin, ampicillin, and chloramphenicol (80.8%, 61.5%, 53.8%, and 50.0%, respectively) and those from animal feces (80.5%, 78.0%, 41.5%, and 46.3%, respectively) in locations housing swine were significantly higher than those from cattle farms (p<0.05). The rates of resistance in E. coli derived from flies reflected those derived from livestock feces at the same locations, suggesting that antimicrobial resistance spreads between livestock and flies on the farms. The results of pulsed-field gel electrophoresis (PFGE) analysis showed that, with a few exceptions, all E. coli isolates differed. Two pairs of tetracycline-resistant strains harbored similar plasmids with the same tetracycline-resistance genes, although the origin (fly or feces), site of isolation, and PFGE patterns of these strains differed. Therefore, flies may disseminate the plasmids between farms. Our results suggest that flies may be involved not only in spreading clones of antimicrobial-resistant bacteria within a farm but also in the widespread dissemination of plasmids with antimicrobial resistance genes between farms.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Dípteros/microbiologia
Farmacorresistência Bacteriana Múltipla/genética
Infecções por Escherichia coli/transmissão
Escherichia coli/genética
Genes Bacterianos
Plasmídeos/metabolismo
[Mh] Termos MeSH secundário: Matadouros
Agricultura
Ampicilina/farmacologia
Criação de Animais Domésticos
Animais
Técnicas de Tipagem Bacteriana
Bovinos
Cloranfenicol/farmacologia
Sulfato de Di-Hidroestreptomicina/farmacologia
Eletroforese em Gel de Campo Pulsado
Escherichia coli/classificação
Escherichia coli/efeitos dos fármacos
Escherichia coli/isolamento & purificação
Infecções por Escherichia coli/microbiologia
Infecções por Escherichia coli/veterinária
Fezes/microbiologia
Variação Genética
Japão
Filogenia
Suínos
Tetraciclina/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 66974FR9Q1 (Chloramphenicol); 7C782967RD (Ampicillin); F8VB5M810T (Tetracycline); T7D4876IUE (Dihydrostreptomycin Sulfate)
[Em] Mês de entrada:1607
[Cu] Atualização por classe:161125
[Lr] Data última revisão:
161125
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150611
[St] Status:MEDLINE
[do] DOI:10.1089/mdr.2015.0033


  5 / 658 MEDLINE  
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Rath, Susanne
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[PMID]:25497889
[Au] Autor:Martínez-Mejía MJ; Rath S
[Ad] Endereço:Institute of Chemistry, University of Campinas - UNICAMP, PO Box 6154, 13084-971 Campinas, SP, Brazil.
[Ti] Título:Use of experimental design to optimize a triple-potential waveform to develop a method for the determination of streptomycin and dihydrostreptomycin in pharmaceutical veterinary dosage forms by HPLC-PAD.
[So] Source:J Pharm Biomed Anal;104:81-9, 2015 Feb.
[Is] ISSN:1873-264X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:An HPLC-PAD method using a gold working electrode and a triple-potential waveform was developed for the simultaneous determination of streptomycin and dihydrostreptomycin in veterinary drugs. Glucose was used as the internal standard, and the triple-potential waveform was optimized using a factorial and a central composite design. The optimum potentials were as follows: amperometric detection, E1=-0.15V; cleaning potential, E2=+0.85V; and reactivation of the electrode surface, E3=-0.65V. For the separation of the aminoglycosides and the internal standard of glucose, a CarboPac™ PA1 anion exchange column was used together with a mobile phase consisting of a 0.070 mol L(-1) sodium hydroxide solution in the isocratic elution mode with a flow rate of 0.8 mL min(-1). The method was validated and applied to the determination of streptomycin and dihydrostreptomycin in veterinary formulations (injection, suspension and ointment) without any previous sample pretreatment, except for the ointments, for which a liquid-liquid extraction was required before HPLC-PAD analysis. The method showed adequate selectivity, with an accuracy of 98-107% and a precision of less than 3.9%.
[Mh] Termos MeSH primário: Antibacterianos/análise
Sulfato de Di-Hidroestreptomicina/análise
Estreptomicina/análise
Drogas Veterinárias/química
[Mh] Termos MeSH secundário: Cromatografia Líquida de Alta Pressão/métodos
Cromatografia Líquida de Alta Pressão/veterinária
Técnicas Eletroquímicas/métodos
Técnicas Eletroquímicas/veterinária
Estrutura Molecular
Reprodutibilidade dos Testes
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Veterinary Drugs); T7D4876IUE (Dihydrostreptomycin Sulfate); Y45QSO73OB (Streptomycin)
[Em] Mês de entrada:1508
[Cu] Atualização por classe:141223
[Lr] Data última revisão:
141223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141216
[St] Status:MEDLINE


  6 / 658 MEDLINE  
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[PMID]:25269252
[Au] Autor:Huang J; Yin Y; Xu J; Liu Y; Chen G; Zhang X; Yang W; Sheng C; Chen H; Zhang R
[Ti] Título:[Determination of streptomycin and dihydrostreptomycin in pollens by high performance liquid chromatography-tandem mass spectrometry].
[So] Source:Se Pu;32(6):566-72, 2014 Jun.
[Is] ISSN:1000-8713
[Cp] País de publicação:China
[La] Idioma:chi
[Ab] Resumo:A method was established for the determination of streptomycin (STR) and dihydrostreptomycin (DHS) in pollens based on high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The sample was extracted and cleaned-up by a C18 solid phase extraction cartridge. The separation was carried out on a Protemix WCX-NP5 column (100 mm x 2.1 mm, 5 microm) with a gradient elution using 5% (v/v) formic acid, 20 mmol/L ammonium acetate and methanol as mobile phases. The analysis of streptomycin and dihydrostreptomycin was performed under electrospray positive ionization mode. The limits of detection (LOD, S/N = 3) and limits of quantification (LOQ, S/N = 10) for the both were 5 microg/kg and 10 microg/kg, respectively. Good linearities (r > 0.99) were achieved for the target compounds over the range of 10-200 microg/L. The recoveries at three spiked levels (10, 20, 50 microg/kg) in the blank matrices, such as pollen pini, corn pollen, camellia pollen, sunflower pollen, rape pollen and bee pollen, were from 76.8% to 100.3% with the relative standard deviations varied from 3.70% to 12.6%. The method is accurate, practical, and can be applied to most of the contaminated matrices. With this method, heptafluorobutyric acid is not required as mobile phase which is harmful to MS spectrometer.
[Mh] Termos MeSH primário: Sulfato de Di-Hidroestreptomicina/análise
Pólen/química
Estreptomicina/análise
[Mh] Termos MeSH secundário: Cromatografia Líquida de Alta Pressão
Extração em Fase Sólida
Espectrometria de Massas em Tandem
[Pt] Tipo de publicação:ENGLISH ABSTRACT; JOURNAL ARTICLE
[Nm] Nome de substância:
T7D4876IUE (Dihydrostreptomycin Sulfate); Y45QSO73OB (Streptomycin)
[Em] Mês de entrada:1509
[Cu] Atualização por classe:161018
[Lr] Data última revisão:
161018
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:141002
[St] Status:MEDLINE


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[PMID]:25205267
[Au] Autor:Iscla I; Wray R; Wei S; Posner B; Blount P
[Ad] Endereço:Department of Physiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, Texas 75390-9040, USA.
[Ti] Título:Streptomycin potency is dependent on MscL channel expression.
[So] Source:Nat Commun;5:4891, 2014 Sep 10.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The antibiotic streptomycin is widely used in the treatment of microbial infections. The primary mechanism of action is inhibition of translation by binding to the ribosome, but how it enters the bacterial cell is unclear. Early in the study of this antibiotic, a mysterious streptomycin-induced potassium efflux preceding any decrease in viability was observed; it was speculated that this changed the electrochemical gradient such that streptomycin better accessed the cytoplasm. Here we use a high-throughput screen to search for compounds targeting the mechanosensitive channel of large conductance (MscL) and find dihydrostreptomycin among the 'hits'. Furthermore, we find that MscL is not only necessary for the previously described streptomycin-induced potassium efflux, but also directly increases MscL activity in electrophysiological studies. The data suggest that gating MscL is a novel mode of action of dihydrostreptomycin, and that MscL's large pore may provide a mechanism for cell entry.
[Mh] Termos MeSH primário: Antibacterianos/farmacologia
Sulfato de Di-Hidroestreptomicina/farmacologia
Proteínas de Escherichia coli/efeitos dos fármacos
Escherichia coli/efeitos dos fármacos
Canais Iônicos/efeitos dos fármacos
Potássio/metabolismo
[Mh] Termos MeSH secundário: Sulfato de Di-Hidroestreptomicina/metabolismo
Escherichia coli/metabolismo
Proteínas de Escherichia coli/metabolismo
Ensaios de Triagem em Larga Escala
Canais Iônicos/metabolismo
Técnicas de Patch-Clamp
Espectinomicina/farmacologia
Estreptomicina/metabolismo
Estreptomicina/farmacologia
Viomicina/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Escherichia coli Proteins); 0 (Ion Channels); 0 (MscL protein, E coli); 93AKI1U6QF (Spectinomycin); RWP5GA015D (Potassium); T7D4876IUE (Dihydrostreptomycin Sulfate); Y45QSO73OB (Streptomycin); YVU35998K5 (Viomycin)
[Em] Mês de entrada:1507
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140911
[St] Status:MEDLINE
[do] DOI:10.1038/ncomms5891


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[PMID]:24741041
[Au] Autor:Marcotti W; Corns LF; Desmonds T; Kirkwood NK; Richardson GP; Kros CJ
[Ad] Endereço:Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, Brighton BN1 9QG, United Kingdom, Department of Biomedical Science, University of Sheffield, Sheffield, S10 2TN, United Kingdom, and Department of Otorhinolaryngology, Head and Neck Surgery, University Medical Center Groningen, University of Groningen, 9700 RB Groningen, The Netherlands.
[Ti] Título:Transduction without tip links in cochlear hair cells is mediated by ion channels with permeation properties distinct from those of the mechano-electrical transducer channel.
[So] Source:J Neurosci;34(16):5505-14, 2014 Apr 16.
[Is] ISSN:1529-2401
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Tip links between adjacent stereocilia are believed to gate mechano-electrical transducer (MET) channels and mediate the electrical responses of sensory hair cells. We found that mouse auditory hair cells that lack tip links due to genetic mutations or exposure to the Ca(2+) chelator BAPTA can, however, still respond to mechanical stimuli. These MET currents have unusual properties and are predominantly of the opposite polarity relative to those measured when tip links are present. There are other striking differences, for example, the channels are usually all closed when the hair cell is not stimulated and the currents in response to strong stimuli can be substantially larger than normal. These anomalous MET currents can also be elicited early in development, before the onset of mechano-electrical transduction with normal response polarity. Current-voltage curves of the anomalous MET currents are linear and do not show the rectification characteristic of normal MET currents. The permeant MET channel blocker dihydrostreptomycin is two orders of magnitude less effective in blocking the anomalous MET currents. The findings suggest the presence of a large population of MET channels with pore properties that are distinct from those of normal MET channels. These channels are not gated by hair-bundle links and can be activated under a variety of conditions in which normal tip-link-mediated transduction is not operational.
[Mh] Termos MeSH primário: Permeabilidade da Membrana Celular/fisiologia
Células Ciliadas Auditivas/fisiologia
Canais Iônicos/fisiologia
Mecanotransdução Celular/fisiologia
[Mh] Termos MeSH secundário: Animais
Animais Recém-Nascidos
Caderinas/genética
Permeabilidade da Membrana Celular/genética
Quelantes/farmacologia
Sulfato de Di-Hidroestreptomicina/farmacologia
Ácido Egtázico/análogos & derivados
Ácido Egtázico/farmacologia
Embrião de Mamíferos
Feminino
Células Ciliadas Auditivas/citologia
Células Ciliadas Auditivas/efeitos dos fármacos
Técnicas In Vitro
Canais Iônicos/efeitos dos fármacos
Masculino
Mecanotransdução Celular/efeitos dos fármacos
Mecanotransdução Celular/genética
Potenciais da Membrana/efeitos dos fármacos
Potenciais da Membrana/genética
Camundongos
Camundongos Endogâmicos C57BL
Camundongos Transgênicos
Miosinas/genética
Órgão Espiral/citologia
Precursores de Proteínas/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Cadherins); 0 (Cdh23 protein, mouse); 0 (Chelating Agents); 0 (Ion Channels); 0 (Pcdh15 protein, mouse); 0 (Protein Precursors); 526U7A2651 (Egtazic Acid); EC 3.6.4.1 (Myosins); EC 3.6.4.1 (myosin VIIa); K22DDW77C0 (1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid); T7D4876IUE (Dihydrostreptomycin Sulfate)
[Em] Mês de entrada:1406
[Cu] Atualização por classe:170922
[Lr] Data última revisão:
170922
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140418
[St] Status:MEDLINE
[do] DOI:10.1523/JNEUROSCI.4086-13.2014


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[PMID]:24731642
[Au] Autor:Mullen KA; Anderson KL; Washburn SP
[Ad] Endereço:Department of Animal Science, North Carolina State University, Raleigh 27695.
[Ti] Título:Effect of 2 herbal intramammary products on milk quantity and quality compared with conventional and no dry cow therapy.
[So] Source:J Dairy Sci;97(6):3509-22, 2014.
[Is] ISSN:1525-3198
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Dry cow therapy, administered at the end of lactation, is aimed at eliminating current and preventing future intramammary (IMM) bacterial infections and typically involves intramammary administration of antibiotics. Certified organic dairies in the United States are restricted from using antibiotics and must consider an alternative therapy or no dry cow therapy. The current study compared 2 herbal products to conventional dry cow therapy and no treatment for a total of 5 treatments over 2 trials. Trial 1 was conducted over 3 yr on 1 research farm and trial 2 included 4 commercial farms plus the research herd over 2 yr. Treatments included (1) a conventional IMM antibiotic and internal teat sealant (penicillin-dihydrostreptomycin and bismuth subnitrate; CON); (2) an herbal IMM product purported to act as a teat sealant (Cinnatube, New AgriTech Enterprises, Locke, NY; CIN); (3) an herbal IMM product (Phyto-Mast, Bovinity Health LLC, Narvon, PA; P-M); (4) Phyto-Mast and Cinnatube (PC); or (5) no dry cow therapy (NT). Each treatment group was balanced by breed, lactation number, due date, herd, and year. However, the CON treatment was used only in the research herd because of the intent to avoid antibiotic usage on the other 4 farms. Comparisons among treatments included the difference between pre- and posttreatment 305-d mature equivalent milk production (trial 1), somatic cell score change from dry-off to freshening at the cow and quarter levels (trials 1 and 2), and milk microbiology change over the dry period (trial 2). We detected no significant differences among treatments for milk yield differences between the lactation following treatment and the lactation preceding treatment. Changes in somatic cell score from one lactation to the next also did not differ significantly among treatments in either trial. Cure rates were not significantly different among treatments; only 19.6% of all quarters were infected at dry off. The proportion of quarters with new infections at 3 to 5d postcalving did not significantly differ among treatments, except between CIN and NT. Percentages (least squares means ± standard error) of quarters with new infections were 24 ± 21% for CON, 15 ± 7% for CIN, 30 ± 10% for P-M, 32 ± 11% for PC, and 35 ± 11% for NT. The efficacy of the herbal products was similar to that of conventional therapy, and the herbal products had no apparent adverse effects.
[Mh] Termos MeSH primário: Infecções Bacterianas/veterinária
Medicamentos de Ervas Chinesas/administração & dosagem
Glândulas Mamárias Animais/efeitos dos fármacos
Glândulas Mamárias Animais/microbiologia
Mastite Bovina/tratamento farmacológico
Leite
[Mh] Termos MeSH secundário: Animais
Antibacterianos/uso terapêutico
Infecções Bacterianas/tratamento farmacológico
Bismuto/uso terapêutico
Bovinos
Dieta/veterinária
Sulfato de Di-Hidroestreptomicina/uso terapêutico
Feminino
Contaminação de Alimentos/prevenção & controle
Microbiologia de Alimentos
Alimentos Orgânicos/microbiologia
Lactação
Mastite Bovina/microbiologia
Leite/microbiologia
Penicilinas/uso terapêutico
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Drugs, Chinese Herbal); 0 (Penicillins); H19J064BA5 (bismuth subnitrate); T7D4876IUE (Dihydrostreptomycin Sulfate); U015TT5I8H (Bismuth)
[Em] Mês de entrada:1510
[Cu] Atualização por classe:140523
[Lr] Data última revisão:
140523
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140416
[St] Status:MEDLINE


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[PMID]:23958025
[Au] Autor:Arruda AG; Godden S; Rapnicki P; Gorden P; Timms L; Aly SS; Lehenbauer TW; Champagne J
[Ad] Endereço:Department of Veterinary Population Medicine, University of Minnesota, Saint Paul 55108.
[Ti] Título:Randomized noninferiority clinical trial evaluating 3 commercial dry cow mastitis preparations: II. Cow health and performance in early lactation.
[So] Source:J Dairy Sci;96(10):6390-9, 2013 Oct.
[Is] ISSN:1525-3198
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The objective of this randomized noninferiority clinical trial was to compare the effect of treatment with 3 different dry cow therapy formulations at dry-off on cow-level health and production parameters in the first 100 d in milk (DIM) in the subsequent lactation, including 305-d mature-equivalent (305 ME) milk production, linear score (LS), risk for the cow experiencing a clinical mastitis event, risk for culling or death, and risk for pregnancy by 100 DIM. A total of 1,091 cows from 6 commercial dairy herds in 4 states (California, Iowa, Minnesota, and Wisconsin) were randomly assigned at dry-off to receive treatment with 1 of 3 commercial products: Quartermaster (QT; Zoetis Animal Health, Madison, NJ), Spectramast DC (SP; Zoetis Animal Health) or ToMorrow Dry Cow (TM; Boehringer Ingelheim Vetmedica Inc., St Joseph, MO). All clinical mastitis, pregnancy, culling, and death events occurring in the first 100 DIM were recorded by farm staff using an on-farm electronic record-keeping system. Dairy Herd Improvement Association test-day records of milk production and milk component testing were retrieved electronically. Mixed linear regression analysis was used to describe the effect of treatment on 305ME milk production and LS recorded on the last Dairy Herd Improvement Association test day before 100 DIM. Cox proportional hazards regression analysis was used to describe the effect of treatment on risk for experiencing a case of clinical mastitis, risk for leaving the herd, and risk for pregnancy between calving and 100 DIM. Results showed no effect of treatment on adjusted mean 305 ME milk production (QT=11,759 kg, SP=11,574 kg, and TM=11,761 kg) or adjusted mean LS (QT=1.8, SP=1.9, and TM=1.6) on the last test day before 100 DIM. Similarly, no effect of treatment was observed on risk for a clinical mastitis event (QT=14.8%, SP=12.7%, and TM=15.0%), risk for leaving the herd (QT=7.5%, SP=9.2%, and TM=10.3%), or risk for pregnancy (QT=31.5%, SP=26.1%, and TM=26.9%) between calving and 100 DIM.
[Mh] Termos MeSH primário: Antibacterianos/uso terapêutico
Cefapirina/uso terapêutico
Sulfato de Di-Hidroestreptomicina/uso terapêutico
Mastite Bovina/tratamento farmacológico
Penicilina G Procaína/uso terapêutico
[Mh] Termos MeSH secundário: Animais
Bovinos
Cefalosporinas/uso terapêutico
Feminino
Lactação/efeitos dos fármacos
Leite/secreção
Minnesota
Gravidez
Risco
[Pt] Tipo de publicação:JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Cephalosporins); 17R794ESYN (Penicillin G Procaine); 83JL932I1C (ceftiofur); 89B59H32VN (Cephapirin); T7D4876IUE (Dihydrostreptomycin Sulfate)
[Em] Mês de entrada:1504
[Cu] Atualização por classe:130923
[Lr] Data última revisão:
130923
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:130821
[St] Status:MEDLINE



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