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Pontas e velocidade de deslocamento na deposição de gotas da pulverização na cultura do algodão

Cavalieri, Jhonatan Diego
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: viii, 73 f. : grafs., tabs.
Português
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Pós-graduação em Agronomia (Proteção de Plantas) - FCA; Dois experimentos foram conduzidos em lavoura comercial de algodão, Gossypium hirsutum L., na safra agrícola 2012/2013, em estádios de desenvolvimento distintos (B9 e F13), para avaliar o efeito de pontas de pulverização de energia hidráulica e um sistema de pulverização de energia centrífuga sob diferentes velocidades de deslocamento do pulverizador sobre o depósito, cobertura e espectro de gotas da pulverização. O delineamento experimental foi o modelo de blocos casualizados, com doze tratamentos e quatro repetições. Os tratamentos foram distribuídos em arranjo fatorial 3 x 4 (três técnicas de pulverização, sendo duas delas de energia hidráulica: jato plano simples; jato plano simples inclinado com indução de ar, sob taxa de aplicação de 120 L.ha-1; e sistema de energia centrífuga - atomizador rotativo de disco - sob taxa de aplicação de 20 L.ha-1, combinadas a quatro velocidades de deslocamento: 12, 15, 18 e 25 km.h-1). Para a avaliação do depósito da pulverização, alvos artificiais foram fixados na superfície adaxial e abaxial das folhas do ápice e base do algodoeiro (Estádio B9) e também na parte média das plantas (Estádio F13). Após a pulverização de um marcador cúprico (oxicloreto de cobre)...

Resposta ovariana e taxa de recuperação embrionária em éguas tratadas com FSH suíno

Ignácio, Fernanda Saules
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 86 f.
Português
Relevância na Pesquisa
17.11%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Pós-graduação em Medicina Veterinária - FMVZ; O presente estudo tem como objetivo verificar a resposta ovulatória e recuperação embrionária em éguas após o tratamento com FSHp (Folltropin-V®) em diferentes momentos, com diferentes doses e na raça BH. O crescimento folicular foi acompanhado diariamente e os tratamentos (i.m. a cada 12h) foram mantidos até que o maior(es) folículo(s) atingiu 32mm, a indução da ovulação (2500 UI de hCG i.v.) foi realizada quando o maior(es) folículo(s) atingiu 35mm e a colheita de embriões no D8. No experimento 1, a dose de 25mg de FSHp foi testada em 28 éguas para determinação do melhor momento após aspiração folicular: 13mm (n=7, salina, controle), 13mm (n=7, FSHp-F13) e 20mm (n=7, FSHp-F20); ou em um dia determinado do ciclo: D6 (n=7, FSHp- D6). No experimento 2, a dose de 50mg de FSHp foi testada em 17 éguas quando o maior folículo atingiu 13mm (n=7, FSHp-13) e comparada ao grupo controle (n=10). No experimento 3, em 26 éguas BH inciou-se os seguintes tratamentos no D6: salina (n=7, controle), 25mg de FSHp (n=7, 25FSHp-D6), 12,5mg de EPE (n=7...

Efeitos antiproliferativos sobre células tumorais das secreções cutâneas dos anuros Leptodactylus Labyrinthicus e Phillomedusa azurea e de seus peptídeos biologicamente ativos sobre o fungo Candida albicans

Chagas, Aline da Silva
Fonte: Universidade de Brasília Publicador: Universidade de Brasília
Tipo: Dissertação
Português
Relevância na Pesquisa
17.11%
Dissertação (mestrado)—Fundação Universidade de Brasília, Instituto de Ciências Biologias, Programa de Pós Graduação em Biologia Animal, 2014.; A secreção cutânea de anuros é reconhecida como uma rica fonte de compostos biologicamente ativos, incluindo aminas biogênicas, alcaloides, bufadienolídeos, peptídeos e proteínas. Os peptídeos antimicrobianos constituem um sistema de defesa imediato, atuando sobre um grande espectro de mircroorganismos. A busca por novas alternativas terapêuticas no tratamento de infecções e câncer tem impulsionado nos estudos voltados à prospecção de novos peptídeos antimicrobianos. No presente trabalho, as secreções cutâneas de Leptodactylus labyrinthicus e Phyllomedusa azurea foram utilizadas para avaliar seus efeitos antiproliferativos e citotóxicos sobre células tumorais. Também foram submetidas a fracionamento cromatográfico a fim de se isolar peptídeos com atividade inibitória sobre a proliferação do fungo patogênico Candida albicans. As frações bioativas foram analisadas por MALDI-TOF MS e submetidas à recromatografia por RP-HPLC. De acordo com a estratégia experimental empregada foi possível a obtenção de duas frações homogêneas a partir da secreção de P. azurea...

Avaliação do Desempenho do Teste de Rastreio de Alergia Alimentar FP5® (DPC-Amerlab)

Marinho, S; Morais-Almeida, M; Loureiro, V; Matos, V; Gaspar, A; Murta, R; Rosado-Pinto, J
Fonte: Sociedade Portuguesa de Alergologia e Imunologia Clínica Publicador: Sociedade Portuguesa de Alergologia e Imunologia Clínica
Tipo: Artigo de Revista Científica
Publicado em //2004 Português
Relevância na Pesquisa
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Introdução: A utilização dos testes de rastreio para detecção de IgE específica sérica para diversos alergénios tem sido discutida, sendo invariavelmente aceite a sua utilidade no que diz respeito aos aeroalergénios, não tendo sido ainda suficientemente estabelecida a eficiência dos testes correspondentes destinados à detecção de alergénios alimentares, como acontece com o FP5® da Diagnostic Products Corporation (contendo mistura de clara de ovo, leite, bacalhau, trigo,soja e amendoim). Objectivo: Avaliar o desempenho do teste FP5®, determinando a sua sensibilidade, especificidade e comparação com os métodos de detecção das correspondentes IgE específicas isoladas. Material e métodos: Foi incluída uma amostra aleatória de 54 soros de crianças com alergia alimentar e com determinações de IgE específica positivas para um ou mais dos alimentos testados pelo FP5® - grupo de estudo; foi seleccionado um grupo controlo de 27 amostras de sangue de crianças sem alergia alimentar e em que a determinação de IgE específica para todos os alimentos incluídos no painel em estudo foi negativa. Em ambos os grupos foi efectuada determinação da concentração de IgE específica sérica (kU/l) para FP5®, F1 (clara de ovo)...

Avaliação do Desempenho do Teste de Rastreio de Alergia Alimentar FP5® (DPC-Amerlab)

Marinho, S; Morais-Almeida, M; Loureiro, V; Matos, V; Gaspar, A; Murta, R; Rosado-Pinto, J
Fonte: Sociedade Portuguesa de Alergologia e Imunologia Clínica Publicador: Sociedade Portuguesa de Alergologia e Imunologia Clínica
Tipo: Artigo de Revista Científica
Publicado em //2004 Português
Relevância na Pesquisa
17.11%
Introdução: A utilização dos testes de rastreio para detecção de IgE específica sérica para diversos alergénios tem sido discutida, sendo invariavelmente aceite a sua utilidade no que diz respeito aos aeroalergénios, não tendo sido ainda suficientemente estabelecida a eficiência dos testes correspondentes destinados à detecção de alergénios alimentares, como acontece com o FP5® da Diagnostic Products Corporation (contendo mistura de clara de ovo, leite, bacalhau, trigo,soja e amendoim). Objectivo: Avaliar o desempenho do teste FP5®, determinando a sua sensibilidade, especificidade e comparação com os métodos de detecção das correspondentes IgE específicas isoladas. Material e métodos: Foi incluída uma amostra aleatória de 54 soros de crianças com alergia alimentar e com determinações de IgE específica positivas para um ou mais dos alimentos testados pelo FP5® - grupo de estudo; foi seleccionado um grupo controlo de 27 amostras de sangue de crianças sem alergia alimentar e em que a determinação de IgE específica para todos os alimentos incluídos no painel em estudo foi negativa. Em ambos os grupos foi efectuada determinação da concentração de IgE específica sérica (kU/l) para FP5®, F1 (clara de ovo)...

Adaptabilidade e estabilidade de genótipos de tomateiro sob cultivo em solos de terra firme e várzea da amazônia infestados por Ralstonia solanacearum

Pena,Maria Albanira Araújo; Noda,Hiroshi; Machado,Francisco Manoares; Paiva,Maria Silvesnízia da Silva
Fonte: Instituto Agronômico de Campinas Publicador: Instituto Agronômico de Campinas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 Português
Relevância na Pesquisa
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A resistência genética à bactéria Ralstonia solanacearum, o patógeno da doença "murcha bacteriana", é uma condição necessária para o cultivo do tomateiro nos solos naturalmente infestados pelo patógeno nos ambientes de terra firme e várzea da região amazônica. Neste trabalho avaliou-se a adaptabilidade e estabilidade quanto à resistência genética ao patógeno e à produtividade de progênies de gerações avançadas (F13 e F14) do cruzamento HT -16, que deu origem à variedade resistente Yoshimatsu, quando cultivadas em solos de terra firme e várzea infestados por R. solanacearum. Foram realizados ensaios em quatro ambientes, dois em terra firme e dois na várzea, em solos naturalmente infestados pelo patógeno e com oito genótipos de tomateiro: Santa Cruz Kada, utilizada como padrão de suscetibilidade ao patógeno; Caraíba, como padrão de resistência; C-38; Yoshimatsu 4-11 e mais quatro progênies F13 e F14 do cruzamento HT-16. Os caracteres utilizados para avaliação da resistência e produtividade foram: Taxa de Infecção (QR), para doenças monocíclicas, segundo PLANK (1963); Índice de Sanidade (IS), segundo NODA (1981); Produção Total de Frutos (PTF) e Número Total de Frutos (NTF). As estimativas dos parâmetros de adaptabilidade e estabilidade fenotípica...

Comparative studies on the biology and filarial susceptibility of selected blood-feeding and autogenous Aedes togoi sub-colonies

Junkum,Anuluck; Choochote,Wej; Jitpakdi,Atchariya; Leemingsawat,Somjai; Komalamisra,Narumon; Jariyapan,Narissara; Boonyatakorn,Chavalit
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2003 Português
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Blood-feeding and autogenous sub-colonies were selected from a laboratory, stock colony of Aedes togoi, which was originally collected from Koh Nom Sao, Chanthaburi province, Southeast Thailand. Comparative biology and filarial susceptibility between the two sub-colonies (blood-feeding: F11, F13; autogeny: F38, F40) were investigated to evaluate their viability and vectorial capacity. The results of comparison on biology revealed intraspecific differences, i.e., the average egg deposition/gravid female (F11/F38; F13/F40), embryonation rate (F13/F40), hatchability rate (F11/F38; F13/F40), egg width (F11/F38), wing length of females (F13/F40), and wing length and width of males (F11/F38) in the blood-feeding sub-colony were significantly greater than that in the autogenous sub-colony; and egg length (F11/F38) and width (F13/F40), and mean longevity of adult females (F11/F38) and males (F13/F40) in the blood-feeding sub-colony were significantly less than that in the autogenous sub-colony. The results of comparison on filarial susceptibility demonstrated that both sub-colonies yielded similar susceptibilities to Brugia malayi [blood-feeding/autogeny = 56.7% (F11)/53.3%(F38), 60%(F13)/83.3%(F40)] and Dirofilaria immitis [blood-feeding/autogeny = 85.7%(F11)/75%(F38)...

Screening and enzymatic study of a composite microbial system FH3

Zhang,Yi-Min; Lu,Xue-Bin; Dan,Han-Bin; Sun,Ya-Kai
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2009 Português
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Five strains of fungi and 18 strains of bacteria were isolated from the soil and horse manure with cellulose as the sole carbon source. Among them, two fungal, F9 and F13, and two bacterial, B16 and B21, showed the highest filter paper activities, which were 7.79 U g-1, 9.84 U g-1, 7.34 U g-1 and 9.68 U g-1, respectively. Four microbial systems, designed as FH1 (F13+B21), FH2 (F13+B16+B21), FH3 (F9+B16+B21) and FH4 (F13+F9+B16+B21) were developed. The fermentation studies showed that the filter paper activity of the composite microbial system FH3 was higher than the others, which was 21.34 U g-1. The medium with bran and filter paper as the carbon source and peptone as nitrogen source was optimal and the maximum cellulase activity was reached at 30~35ºC and pH 6.0~6.5 when FH3 was incubated for 48 h. The enzymatic reaction conditions were estimated at 45~55 ºC, pH 4.5~5.5 and the thermal stability temperature was up to 60 ºC.

Structure and antigenic properties of the tip-located P pilus proteins of uropathogenic Escherichia coli.

Lund, B; Lindberg, F; Normark, S
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /04/1988 Português
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Pyelonephritogenic Escherichia coli frequently expresses pili which bind to Gal alpha (1-4)Gal receptors present on the uroepithelium. Binding of these pili is mediated by a pilus-associated adhesin, PapG, and not by the major subunit which constitutes the bulk of the pilus structure. The adhesin and two pilinlike proteins, PapE and PapF, are present in only a few copies each at the pilus tip. Surface exposure of both PapF and PapG is required to achieve receptor-specific binding. The nucleotide sequences for the genes encoding the tip-associated proteins PapE, PapF, and PapG were determined for two E. coli clones expressing P pili of serotypes F11 and F7(2) and compared with the corresponding sequences established for proteins of F13 pili. Specific antisera were used to study the cross-reactivity between the F13 tip proteins and the equivalent proteins in F11 and F7(2) pili. We present data showing that, like the major pilus subunit, PapE varies its structure and antigenic properties among pili of different serotypes. In contrast, the PapF protein was highly conserved, and PapF-specific antisera raised against serotype F13 cross-reacted with the PapF proteins of both F11 and F7(2) serotypes. The PapG adhesin protein from F11 and F7(2) pili differed by only five amino acids out of 316 residues. However...

Transfer and Incorporation of Genes Controlling β-d-Galactosidase Synthesis from Hfr and F′ Donors of Escherichia coli1

Ganesan, Ann K.; Rotman, Boris
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1966 Português
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Ganesan, Ann K. (Syntex Institute of Molecular Biology, Palo Alto, Calif.), and Boris Rotman. Transfer and incorporation of genes controlling β-d-galactosidase synthesis from Hfr and F′ donors of Escherichia coli. J. Bacteriol. 92:1378–1382. 1966.—Comparisons were made between Hfr1 and F13 donors with respect to the frequency of transfer and incorporation of genes controlling β-d-galactosidase synthesis. The Hfr1 donor transfers these genes as part of the chromosome, and the F13 donor transfers them by F-duction. The criterion used for gene transfer was the acquisition by recipient cells of the ability to synthesize the enzyme, β-d-galactosidase, measured by fluorogenic assays at the single-cell level. The criterion for incorporation was the formation of lac+ recombinant colonies. It was found that the two types of donor showed the same frequency of gene transfer, but the probability of incorporation was 10-fold higher in F13 matings than in Hfr1 matings. In the former, between 46 and 97% of the merozygotes produced recombinant colonies; in the latter, 2 to 6% did so.

Isolation and characterization of the alpha-galactosyl-1,4-beta-galactosyl-specific adhesin (P adhesin) from fimbriated Escherichia coli.

Hoschützky, H; Lottspeich, F; Jann, K
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/1989 Português
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17.6%
The alpha-galactosyl-1,4-beta-galactosyl-specific adhesin (P adhesin) was isolated from the fimbria-adhesin complex (FAC) of recombinant Escherichia coli strains expressing the F7(1), F8, or F13 fimbrial antigens. Separation into fimbriae and adhesin was achieved by heating the FAC to 80 degrees C in the presence of Zwittergent 3-16. After removal of the fimbriae by precipitation with lithium chloride, the adhesin was purified by anion-exchange fast protein liquid chromatography in the presence of 4 M urea. The purified adhesins from the three strains had pIs of 4.8 to 5.0 and molecular weights of approximately 35,000. The fimbrillins were smaller, their molecular weights being different with different F antigens. The amino-terminal amino acid sequence of the F7(1)- and F13-derived adhesins were different, that of the F13-derived adhesin being identical to that extrapolated from the DNA sequence of the papG gene (B. Lund, G. Lindberg, B.-I. Marklund, and S. Normark, Proc. Natl. Acad. Sci. USA 84:5898-5902). An antiadhesive monoclonal antibody which reacted with the three P adhesins was prepared. The FAC and the purified adhesins but not the fimbriae from which the adhesins had been removed agglutinated erythrocytes and galactose-galactose-coated latex beads. The adhesion of erythrocytes to the surface-fixed adhesins could be specifically inhibited with alpha-galactosyl-1...

The cytoplasmic domain of alphavirus E2 glycoprotein contains a short linear recognition signal required for viral budding.

Kail, M; Hollinshead, M; Ansorge, W; Pepperkok, R; Frank, R; Griffiths, G; Vaux, D
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1991 Português
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17.42%
Intracellular alphavirus nucleocapsids express a binding site for the cytoplasmic domain of the viral E2 spike glycoprotein. This binding site is recognized by the anti-idiotype monoclonal antibody, F13. The monoclonal anti-anti-idiotype antibody, raised against F13 and designated 3G10, recognizes the carboxy-terminal eight residues of the E2 cytoplasmic domain in Semliki Forest virus (SFV), identifying this as the signal for nucleocapsid interaction. F13 binding to cells infected with SFV or a second alphavirus, Sindbis virus, is inhibited by a synthetic peptide corresponding to the entire 31 residue cytoplasmic domain (E2c), and also by a synthetic peptide corresponding to the eight residue epitope recognized by 3G10. Both E2c and the eight residue peptide inhibited viral budding in microinjection experiments and when conjugated to colloidal gold are bound specifically to nucleocapsids in infected cells. These results identify a short linear signal in the E2 cytoplasmic domain required for the interaction with nucleocapsids which leads to budding of at least two alphaviruses from infected cells.

Vaccinia Virus A34 Glycoprotein Determines the Protein Composition of the Extracellular Virus Envelope▿

Perdiguero, Beatriz; Lorenzo, María M.; Blasco, Rafael
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
17.42%
The outer envelope of the extracellular form of vaccinia virus contains five virus-encoded proteins, F13, A33, A34, A56, and B5, that, with the exception of A56, are implicated in virus egress or infectivity. A34, a type II transmembrane glycoprotein, is involved in the induction of actin tails, the release of enveloped virus from the surfaces of infected cells, and the disruption of the virus envelope after ligand binding prior to virus entry. To investigate interactions between A34 and other envelope proteins, a recombinant vaccinia virus (vA34RHA) expressing an epitope-tagged version of A34 (A34HA) was constructed by appending an epitope from influenza virus hemagglutinin to the C terminus of A34. Complexes of A34HA with B5 and A36, but not with A33 or F13, were detected in vA34RHA-infected cells. A series of vaccinia viruses expressing mutated versions of the B5 protein was used to investigate the domain(s) of B5 required for interaction with A34. Both the cytoplasmic and the transmembrane domains of B5 were dispensable for binding to A34. Most of the extracellular domain of B5, which contains four short consensus repeats homologous to complement control proteins, was sufficient for A34 interaction, indicating that both proteins interact through their ectodomains. Immunofluorescence experiments on cells infected with A34-deficient virus indicated that A34 is required for efficient targeting of B5...

Cytotoxicity on Human Cancer Cells of Ophidiacerebrosides Isolated from the African Starfish Narcissia canariensis

Farokhi, Fereshteh; Wielgosz-Collin, Gaetane; Clement, Monique; Kornprobst, Jean-Michel; Barnathan, Gilles
Fonte: Molecular Diversity Preservation International Publicador: Molecular Diversity Preservation International
Tipo: Artigo de Revista Científica
Publicado em 22/12/2010 Português
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The starfish Narcissia canariensis harvested from the coasts off Dakar, Senegal, was investigated for glycolipids (GL). This report deals with the isolation, characterization and biological activity of a fraction F13-3 separated from the GL mixture and selected according to its ability to inhibit KB cell proliferation after 72 hours of treatment. Firstly, a GL mixture F13 was obtained that accounted for 1.36% of starfish biomass (dry weight) and 0.36% of total lipids. The fraction F13-3 obtained from F13 contained three homologous GL identified as peracetylated derivatives on the basis of chemical and spectroscopic evidence. These contained a β-glucopyranoside as sugar head, a 9-methyl-branched 4,8,10-triunsaturated long-chain aminoalcohol as sphingoid base and amide-linked 2-hydroxy fatty acid chains. The majority (63%) had an amide-linked 2-hydroxydocosanoic acid chain and was identified as the ophidiacerebroside-C, firstly isolated from the starfish Ophidiaster ophidiamus. The minor components of F13-3 differed by one more or one less methylene group, and corresponded to ophidiacerebroside-B and -D. We found that F13-3 displayed an interesting cytotoxic activity over 24 hours on various adherent human cancerous cell lines (multiple myeloma...

Dust from hog confinement facilities impairs Ca2+ mobilization from sarco(endo)plasmic reticulum by inhibiting ryanodine receptors

Tian, Chengju; Moore, Caronda J.; Dodmane, Puttappa; Shao, Chun Hong; Romberger, Debra J.; Toews, Myron L.; Bidasee, Keshore R.
Fonte: American Physiological Society Publicador: American Physiological Society
Tipo: Artigo de Revista Científica
Português
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Individuals working in commercial hog confinement facilities have elevated incidences of headaches, depression, nausea, skeletal muscle weakness, fatigue, gastrointestinal disorders, and cardiovascular diseases, and the molecular mechanisms for these nonrespiratory ailments remain incompletely undefined. A common element underlying these diverse pathophysiologies is perturbation of intracellular Ca2+ homeostasis. This study assessed whether the dust generated inside hog confinement facilities contains compounds that alter Ca2+ mobilization via ryanodine receptors (RyRs), key intracellular channels responsible for mobilizing Ca2+ from internal stores to elicit an array of physiologic functions. Hog barn dust (HBD) was extracted with phosphate-buffered saline, sterile-filtered (0.22 μm), and size-separated using Sephadex G-100 resin. Fractions (F) 1 through 9 (Mw >10,000 Da) had no measurable effects on RyR isoforms. However, F10 through F17, which contained compounds of Mw ≤2,000 Da, modulated the [3H]ryanodine binding to RyR1, RyR2, and RyR3 in a biphasic (Gaussian) manner. The Ki values for F13, the most potent fraction, were 3.8 ± 0.2 μg/ml for RyR1, 0.2 ± 0.01 μg/ml and 19.1 ± 2.8 μg/ml for RyR2 (two binding sites), and 44.9 ± 2.8 μg/ml and 501.6 ± 9.2 μg/ml for RyR3 (two binding sites). In lipid bilayer assays...

In situ Gel of Metoprolol Tartrate: Physicochemical Characterization, In vitro Diffusion and Histological Studies

Khan, S.; Gajbhiye, C.; Singhavi, D. J.; Yeole, P.
Fonte: Medknow Publications & Media Pvt Ltd Publicador: Medknow Publications & Media Pvt Ltd
Tipo: Artigo de Revista Científica
Publicado em //2012 Português
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17.73%
The purpose of the present investigation was to prepare an intranasal in situ gel with increased nasal residence time in order to improve bioavailability of metoprolol tartrate. The in situ gel systems containing carbopol, hydroxypropyl methylcellulose K4M and K15M in different concentrations were prepared. The samples were characterized for viscosity, rheological behavior, gelation behavior, gel strength, and mucoadhesion. The formulations F10 (0.4% w/v carbopol, 1% w/v hydroxylpropyl methylcellulose K15M) and F13 (0.3% w/v carbopol, 1% w/v hydroxypropyl methylcellulose K15M) showed gel strength of 40.33±0.47 and 43.00±1.41, respectively, and mucoadhesion strength 31.48±0.14×103 and 32.12±0.05×103 dyne/cm2, respectively. In vitro release profiles showed initial burst followed by slow release. F10 and F13 released 88.08±0.98 and 91.18±1.09% drug in 8 h. R2 value for F10 (0.9953) and F13 (0.9942) was maximum for Higuchi, showing mixed order kinetics while n value obtained on treatment with Korsemayer Pappas equation were near to 0.5, suggesting release by fickian diffusion mechanism. The nasal permeability of formulations F10 and F13 were found to be 0.057 and 0.063 cm/s, respectively. Histopathological examination revealed slight degeneration of nasal epithelium with increased vascularity by F10 but no inflammation by formulation F13. Thus...

Aldehyde oxidase carrying an unusual subunit structure from Pseudomonas sp. MX‐058

Thiwthong, Rungruedee; Kataoka, Michihiko; Iwasaki, Akira; Watanabe, Hiroshi; Hasegawa, Junzo; Isobe, Kimiyasu; Shimizu, Sakayu
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
Português
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Pseudomonas sp. MX‐058 produces aldehyde oxidase catalysing glyoxal to glyoxylic acid. Two aldehyde oxidases (F10 and F13) were purified to homogeneity from Pseudomonas sp. MX‐058. F10 and F13 had subunit structures, a heterotetramer and heteropentamer respectively. The N‐terminal amino acid sequences of all subunits were highly homologous to amino acid sequences of the putative oxidoreductases of Pseudomonas strains. All of these homologous oxidoreductases have a heterotrimer structure consisting of 85‐88 (α), 37‐39 (β) and 18‐23 (γ) kDa subunits. However, the α‐subunits of F10 and F13 might have decomposed into two [80 (α1) and 9 kDa (α2)] and three [58 (α1′), 22 (α1″) and 9 (α2) kDa] subunits, respectively, while the β‐ and γ‐subunits remained intact. Both F10 and F13 show high activity toward several aliphatic and aromatic aldehydes. The aldehyde oxidases of Pseudomonas sp. MX‐058 has unique protein structures, α1α2βγ for F10 and α1′α1″α2βγ for F13, a heterotetramer and heteropentamer respectively. The enzymes exhibit significantly low activity toward glyoxylic acid compared with glyoxal, which is an advantageous property for glyoxylic acid production from glyoxal.

A Promising Approach to Provide Appropriate Colon Target Drug Delivery Systems of Vancomycin HCL: Pharmaceutical and Microbiological Studies

Elkhodairy, Kadria A.; Afifi, Samar A.; Zakaria, Azza S.
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
17.6%
Vancomycin HCl was prepared as orally administered colon target drug delivery tablets for systemic therapy. Tablet matrices containing 10–60% of tablet weight of guar gum (F1–F6) were prepared by direct compression and subjected to in vitro release studies to explore their sustained release in the colon. Various synthetic and natural polymers were incorporated to F6 to modify the drug release rate. Different 15 matrix tablet formulations (F6–F20) were enteric coated with hydroxypropyl methyl cellulose phthalate. F6, F13 and F20 showed promising sustained release results having median dissolution time (MDT) values: 8.25, 7.97, and 7.64, respectively. Microbiological assay was performed to test the efficacy of F6, F13, and F20 to inhibit clinical Staphylococcus aureus (SA) isolates. Bactericidal activity of F6 was reached after 2, 4, and 24 hours of incubation against MSSA 18, MRSA 29, and MRSA 11 strains, respectively, while it was reached within 6–8 hours in case of F13, and F20 against all strains tested. F13 enhanced log microbial reduction by 1.74, 0.65 and 2.4 CFU/mL compared to F6 while it was 1, 2.57 and 1.57 compared to F20 against MSSA18, MRSA11 and MRSA29, respectively. Vancomycin HCl tablets displayed a promising sustained release in vitro and microbiological inhibitory action on all isolates tested.

Electron microscopic heteroduplex studies of sequence relations among plasmids of Escherichia coli: structure of F13 and related F-primes.

Hu, S; Ohtsubo, E; Davidson, N
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /05/1975 Português
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28.05%
The structure of F13, a plasmid containing lac, purE, and proC, has been determined by heteroduplex analysis. As expected for an F-prime formed by a type II excision event, it contains all the sequences of F plus a large segment of Escherichia coli chromosomal deoxyribonucleic acid. There is a sequence of F with coordinates 16.3-17.6F which has been shown in other studies to be the insertion sequence IS2. This IS2 occurs twice on F13, once at each of the two junctions of F deoxyribonucleic acid with chromosomal deoxyribonucleic acid. The sequence alpha beta which occurs twice on F with coordinates 93.2-94.5/OF and 13.7-15.0F occurs an additional three times, twice in an inverted order relative to the alpha beta sequences of F, on the chromosomal sequences of F13. The structures of the plasmids F13-4 and F210 have been determined. The common sequences of F13 with F152-1 (a derivative of F152, the classical F2gal) and with F13-4 and F210 have been mapped. These results partially map lac, proC, tsx, and purE on F13. On the basis of all of these results, it is proposed that Hfr 13 (the parent of F13) was formed by recirpocal recombination between IS2 on F and an IS2 resident at a point between lac and proC on the chromosome of the F+ parent of Hfr 13. It is proposed that this IS2 and the several alpha beta sequences on the chromosomal part of F13 are hot spots for recombination with F...

Electron microscopic heteroduplex studies of sequence relations among plasmids of Escherichia coli: structure of F13 and related F-primes

Hu, Sylvia; Ohtsubo, Eiichi; Davidson, Norman
Fonte: Instituto de Tecnologia da Califórnia Publicador: Instituto de Tecnologia da Califórnia
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em /05/1975 Português
Relevância na Pesquisa
28.05%
The structure of F13, a plasmid containing lac, purE, and proC, has been determined by heteroduplex analysis. As expected for an F-prime formed by a type II excision event, it contains all the sequences of F plus a large segment of Escherichia coli chromosomal deoxyribonucleic acid. There is a sequence of F with coordinates 16.3-17.6F which has been shown in other studies to be the insertion sequence IS2. This IS2 occurs twice on F13, once at each of the two junctions of F deoxyribonucleic acid with chromosomal deoxyribonucleic acid. The sequence alpha beta which occurs twice on F with coordinates 93.2-94.5/OF and 13.7-15.0F occurs an additional three times, twice in an inverted order relative to the alpha beta sequences of F, on the chromosomal sequences of F13. The structures of the plasmids F13-4 and F210 have been determined. The common sequences of F13 with F152-1 (a derivative of F152, the classical F2gal) and with F13-4 and F210 have been mapped. These results partially map lac, proC, tsx, and purE on F13. On the basis of all of these results, it is proposed that Hfr 13 (the parent of F13) was formed by recirpocal recombination between IS2 on F and an IS2 resident at a point between lac and proC on the chromosome of the F+ parent of Hfr 13. It is proposed that this IS2 and the several alpha beta sequences on the chromosomal part of F13 are hot spots for recombination with F...