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1.
Biosci. j. (Online) ; 35(4): 1022-1032, july/aug. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1048810

RESUMO

This study evaluated the effects of the sugarcane borer Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) on cultivars of sweet and biomass sorghum for the selection of resistant cultivars. The present work consisted of two trials, with natural pest infestation. In the first one, 10 sweet sorghum cultivars were analyzed for the following variables: plant height, number of healthy and damaged internodes, gallery position and size, stem infestation level and soluble solids content (°Brix). In the second trial, it was analyzed 16 genotypes of high biomass sorghum, with the same variables above mentioned, in addition to the lignin, cellulose and hemicellulose contents. Among sweet sorghum genotypes evaluated, the genotype CMSXS647 stood out due to the traits: plant height, infestation level, gallery size and soluble solids content. Among the sorghum genotypes evaluated, CMSXS7030, CMSXS7012 and CMSXS7028 presented ideal characteristics for infestation level, plant height and number of lignocellulosic compounds. Such information, in addition to supporting the bioenergy sorghum breeding program, will assist in integrated pest management for sorghum cultivation.


Foram estudados os efeitos causados pela broca-do-colmo Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae), em cultivares de sorgo sacarino e biomassa visando seleção de cultivares resistentes à praga. O presente trabalho foi constituído de dois ensaios, com infestação natural da praga. No primeiro, 10 cultivares de sorgo sacarino foram analisadas quanto às seguintes variáveis: altura das plantas, quantidade de internódios sadios e com injúrias, posição e tamanho da galeria, intensidade de infestação de colmos e teor de sólidos solúveis (°Brix). No segundo ensaio, foram analisados 16 genótipos de sorgo biomassa, com as mesmas variáveis supracitadas, além dos teores de lignina, celulose e hemicelulose. Entre os genótipos de sorgo sacarino avaliados, o genótipo CMSXS647 foi o que se destacou em função das características: altura de plantas, intensidade de infestação, tamanho de galerias e teor de sólidos solúveis. Entre os genótipos de sorgo biomassa avaliados: CMSXS7030, CMSXS7012 e CMSXS7028 apresentaram características ideais para intensidade de infestação, altura de plantas e quantidade de compostos lignocelulósico. Tais informações, além de prover o programa de melhoramento de sorgo energia podem ajudar o programa de MIP para a cultura do sorgo, uma vez que o produtor conhece a suscetibilidade dos materiais escolhidos.


Assuntos
Parede Celular , Biomassa , Sorghum , Lepidópteros
2.
Braz. j. microbiol ; 49(2): 407-413, Apr.-June 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-889247

RESUMO

Abstract Fungal infections have become a concern for health professionals, and the emergence of resistant strains has been reported for all known classes of antifungal drugs. Among the fungi causing disease, we highlight those that belong to the genus Aspergillus. For these reasons, the search for new antifungals is important. This study examines the effects of a coumarin derivative, 4-acetatecoumarin (Cou-UMB16) both alone and together with antifungal drugs, and its mode of action against Aspergillus spp. Cou-UMB16 was tested to evaluate its effects on mycelia growth, and germination of Aspergillus spp. fungal conidia. We investigated its possible action on cell walls, on the cell membrane, and also the capacity of this coumarin derivative to enhance the activity of antifungal drugs. Our results suggest that Cou-UMB16 inhibits Aspergillus spp. virulence factors (mycelia growth and germination of conidia) and affects the structure of the fungal cell wall. When applying Cou-UMB16 in combination with azoles, both synergistic and additive effects were observed. This study concludes that Cou-UMB16 inhibits mycelial growth and spore germination, and that the activity is due to its action on the fungal cell wall, and that Cou-UMB16 could act as an antifungal modifier.


Assuntos
Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Sinergismo Farmacológico , Aspergillus/crescimento & desenvolvimento , Azóis/farmacologia , Membrana Celular/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/crescimento & desenvolvimento
3.
Rev. Eugenio Espejo ; 12(1): 17-30, Jun.- 2018.
Artigo em Espanhol | LILACS | ID: biblio-980670

RESUMO

En Schizosaccharomyces pombe se han descrito tres cascadas de MAPKs: la de respuesta feromonas, con Spk1p como MAP kinasa; la de respuesta a estrés en la que Sty1p/Spc1p es la MAPK y la de mantenimiento de la integridad celular liderada por Pmk1p/Spm1p. La eliminación de cualquiera de las kinasas de la ruta de integridad provoca alteraciones morfo-lógicas y células multitabicadas en condiciones de estrés. Todos estos defectos sugieren una función en homeostasis iónica y en la biosíntesis de la pared celular por lo que nos propone-mos estudiar el papel de la ruta de señalización de MAPK Pmk1p en el mantenimiento de la integridad celular en S.pombe. En este trabajo el organismo mayoritariamente utilizado ha sido la levadura de fisión S. pombe y para realizar los trabajos de clonación molecular se utili-zaron también diferentes estirpes de Escherichia coli. Se emplearon diversas técnicas de clonación molecular, métodos genéticos, Western Blot y determinación de la actividad de Pmk1p bajo condiciones de estrés. Las conclusiones más importantes fueron: que los "senso-res" "Mtl2p y Wsc1p" señalizan hacia Rho1p, pero no son componentes "auténticos" de la cascada, y sus mutantes no presentan el fenotipo VIC (viable en presencia de inmunosupresor y de iones cloruro), característico de los mutantes en los componentes de la cascada. Mtl2p y Wsc1p no desempeñan un papel importante en la señalización en respuesta a estrés osmótico y daño en la pared celular a través de la ruta de integridad celular de Pmk1p.


Three cascades of MAPKs have been described about the Schizosaccharomyces pombe such as: the pheromone response with Spk1p as MAP kinase, the stress response in which Sty1p/Spc1p is MAPK, and the maintenance of cell integrity led by Pmk1p/Spm1p. The elimination of any of the kinases of the integrity path causes morphological alterations and multitabicated cells under stress conditions; suggesting a role in ionic homeostasis and cell wall biosynthesis. So, it was proposed to study the role of the MAPK Pmk1p signaling pathway in the maintenance of cell integrity in S.pombe. The organism mainly used was the fission yeast S. pombe and different molecular strains of Escherichia coli were used to carry out the molecular cloning work. Different techniques of molecular cloning, genetic methods, Western Blot and determination of the activity of Pmk1p under stress conditions were used. The most important conclusions were that the "sensors" "Mtl2p and Wsc1p" signal towards Rho1p but they are not "authentic" components of the cascade, and their mutants do not present the Vic phenotype (viable in the presence of immunosuppressant and chloride ion), characteristic of the mutants in the components of the cascade. Mtl2p and Wsc1p do not play an important role in signaling in response to osmotic stress and cell wall damage through the cellular integrity pathway of Pmk1p.


Assuntos
Humanos , Schizosaccharomyces , Biomarcadores , Parede Celular
4.
Mem. Inst. Oswaldo Cruz ; 113(7): e180040, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-894938

RESUMO

Cryptococcus neoformans is an opportunistic fungal pathogen that is ubiquitous in the environment. It causes a deadly meningitis that is responsible for over 180,000 deaths worldwide each year, including 15% of all AIDS-related deaths. The high mortality rates for this infection, even with treatment, suggest a need for improved therapy. Unique characteristics of C. neoformans may suggest directions for drug discovery. These include features of three structures that surround the cell: the plasma membrane, the cell wall around it, and the outermost polysaccharide capsule. We review current knowledge of the fundamental biology of these fascinating structures and highlight open questions in the field, with the goal of stimulating further investigation that will advance basic knowledge and human health.


Assuntos
Humanos , Polissacarídeos , Cryptococcus neoformans , Membrana Celular , Parede Celular
5.
Electron. j. biotechnol ; 26: 12-19, Mar. 2017. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1009164

RESUMO

Background: Expansins play an important role in cell wall metabolism and fruit softening. Determination of expansin activity is a challenging problem since it depends on measuring cell wall properties by using ad hoc extensometers, a fact that has strongly restricted its study. Then, the objective of the work was to adapt a methodology to measure cell wall creep and expansin activity using a commercial texture meter, equipped with miniature tensile grips and an ad hoc cuvette of easy construction. Results: It was possible to measure hypocotyls acid growth and expansin activity in a reliable and reproducible way, using a commercial texture meter, common equipment found in laboratories of food science or postharvest technology. Expansin activity was detected in protein extracts from cucumber hypocotyls, tomato and strawberry fruits, and statistical differences in expansin activity were found in both fruit models at different ripening stages. Conclusions: The possibility of measuring expansin activity following this adapted protocol with a commercial texture meter could contribute to ease and increase the analysis of expansin in different systems, leading to a better understanding of the properties of these proteins under different experimental conditions.


Assuntos
Proteínas de Plantas/metabolismo , Lycopersicon esculentum/metabolismo , Cucumis sativus/metabolismo , Fragaria/metabolismo , Proteínas de Plantas/análise , Parede Celular/metabolismo , Hipocótilo/crescimento & desenvolvimento , Elasticidade , Frutas/metabolismo
6.
Braz. j. microbiol ; 47(1): 25-32, Jan.-Mar. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-775113

RESUMO

Abstract Twelve isolates of Trichoderma spp. isolated from tobacco rhizosphere were evaluated for their ability to produce chitinase and β-1,3-glucanase extracellular hydrolytic enzymes. Isolates ThJt1 and TvHt2, out of 12 isolates, produced maximum activities of chitinase and β-1,3-glucanase, respectively. In vitro production of chitinase and β-1,3-glucanase by isolates ThJt1 and TvHt2 was tested under different cultural conditions. The enzyme activities were significantly influenced by acidic pH and the optimum temperature was 30 °C. The chitin and cell walls of Sclerotium rolfsii, as carbon sources, supported the maximum and significantly higher chitinase activity by both isolates. The chitinase activity of isolate ThJt1 was suppressed significantly by fructose (80.28%), followed by glucose (77.42%), whereas the β-1,3-glucanase activity of ThJt1 and both enzymes of isolate TvHt2 were significantly suppressed by fructose, followed by sucrose. Ammonium nitrate as nitrogen source supported the maximum activity of chitinase in both isolates, whereas urea was a poor nitrogen source. Production of both enzymes by the isolates was significantly influenced by the cultural conditions. Thus, the isolates ThJt1 and TvHt2 showed higher levels of chitinase and β-1,3-glucanase activities and were capable of hydrolyzing the mycelium of S. rolfsii infecting tobacco. These organisms can be used therefore for assessment of their synergism in biomass production and biocontrol efficacy and for their field biocontrol ability against S. rolfsii and Pythium aphanidermatum infecting tobacco.


Assuntos
Quitinases , Microbiologia do Solo , Trichoderma/enzimologia , Trichoderma/crescimento & desenvolvimento , Basidiomycota/metabolismo , Carbono/metabolismo , Parede Celular/metabolismo , Quitina/metabolismo , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Rizosfera , Temperatura , Tabaco , Trichoderma/isolamento & purificação
7.
J. pediatr. (Rio J.) ; 91(2): 143-151, Mar-Apr/2015. tab
Artigo em Inglês | LILACS | ID: lil-745948

RESUMO

OBJECTIVE: To estimate the association between the implementation of the Brazilian Breastfeeding Network and prevalence of breastfeeding in a medium-size city in southern Brazil. METHODS: This was a cross-sectional study involving 405 children under 1 year who participated in the second phase of the multivaccination campaign in 2012. Children's consumption of food on the day before the interview was obtained through interviews with mothers or guardians. The manager and one health professional from every health facility that joined the Network were interviewed in order to investigate the process of implementation of this initiative. The association between prevalence of breastfeeding and exclusive breastfeeding and adherence to the Network implementation process was tested using Poisson regression with robust variance. RESULTS: Multivariate analysis revealed that among the children assisted by health facilities who joined the Network and those attending services that did not adhere to this strategy, the prevalence of breastfeeding (74% and 70.4% among children under 1 year, respectively) and exclusive breastfeeding (43.3% and 38.1% among children under 6 months, respectively) did not differ significantly. Difficulties in implementing the Network, such as high turnover of professionals, not meeting the criteria for accreditation, and insufficient participation of tutors in the process were identified. CONCLUSION: Contrary to the hypothesis of this study, there was no significant association between the implementation of the Brazilian Breastfeeding Network and prevalence of breastfeeding and exclusive breastfeeding in the studied city. It is possible that the difficulties found in implementing the Network in this city have influenced this result. .


OBJETIVO: Estimar a associação entre a implementação da Rede Amamenta Brasil e as prevalências de aleitamento materno (AM) em um município de médio porte do sul do Brasil. MÉTODOS: Estudo transversal que envolveu 405 crianças menores de um ano que participaram da segunda fase da campanha de multivacinação de 2012. O consumo de alimentos pela criança no dia anterior à entrevista foi obtido mediante entrevistas com as mães ou os responsáveis. Para investigar o processo de implementação da rede foram entrevistados o gerente e um profissional de saúde de cada unidade que aderiu a esse processo. A associação entre as prevalências de AM e AM exclusivo e a adesão ao processo de implementação da rede foi testada com a regressão de Poisson com variância robusta. RESULTADOS: A análise multivariada revelou que entre as crianças assistidas por unidades que aderiram ao processo de implementação da rede e as que frequentam serviços que não aderiram a essa estratégia as prevalências de AM (74% e 70,4% em menores de um ano, respectivamente) e AME (43,3% e 38,1% em menores de seis meses, respectivamente) não diferiram significativamente. Foram identificadas dificuldades na implementação da rede, tais como alta rotatividade dos profissionais, não cumprimento dos critérios para certificação e acompanhamento insuficiente das unidades pelos tutores da rede. CONCLUSÃO: Contrariando a nossa hipótese, não houve associação significativa entre a implementação da Rede Amamenta Brasil e as prevalências de AM e AME no município estudado. É possível que as dificuldades encontradas na implementação da rede nesse município tenham influenciado esse resultado. .


Assuntos
Parede Celular/química , Peptidoglicano/química , Bactérias/química , Bactérias/citologia , Imageamento Tridimensional , Modelos Moleculares , Peptidoglicano/ultraestrutura
8.
São Paulo; s.n; 2015. [132] p. graf, tab, ilus.
Tese em Português | LILACS, Sec. Est. Saúde SP | ID: lil-773065

RESUMO

Os objetivos deste trabalho foram determinar frequência e características de polimorfismo celular em isolados clínicos de Cryptococcus spp. e utilizar novo método de inóculo individualizado para teste de suscetibilidade a antifúngicos (TSA) utilizando isolados de pacientes hospitalizados. O estudo de polimorfismo analisou 112 isolados de C. neoformans (Cn) e 65 de C. gattii (Cg), empregandomicroscopia ótica e microscopia eletrônica de transmissão (MET), análise de melanização, TSA a fluconazol (FCZ) e anfotericina B (AmB) por E-test® e curvas de morte (Time Kill Curves, TK) para AmB, tipagem molecular e mating-type (MAT). O estudo do novo método empregou a carga fúngica de 6 pacientes em suas amostras de líquido cefalorraquidiano (LCR) no momento do diagnóstico,7°dia e 14°dia de terapia antifúngica para CSNC. As cepas foram classificadas segundo tipo molecular e MAT, TSA com FCZ e AMB e teste de combinação por tabuleiro do xadrez. A frequência de polimorfismo celular foi baixa (4%;7/177), mas nunca antes relatada em isolados de micoteca. Foi inédito o encontro de polimorfismo em isolados de sangue, indicando a facilidade de disseminação decélulas atípicas pela corrente sanguínea, assim como em isolado de LCR. Todos os fenótipos polimórficos apresentavam células titãs (100%; 7/7) e, em menor porcentagem, pseudohifas (43%; 3/7). O fenômeno de polimorfismo parece ser exclusivo de Cn, desde que não foi observado em Cg. A espessura da parede das células titãs apresentou a mesma variação (350 nm a 900 nm) em relação àscélulas...


Our objectives were to describe the frequency and characteristics of polymorphismamong clinical isolates of Cryptococcus spp. and use new method of individualizedinoculum for the test of susceptibility to antifungal agents (TSA) against theetiological agent of cryptococcosis of the central nervous system (CSNC) inhospitalized patients. The study of polymorphism analyzed 112 isolates of C.neoformans (Cn) and 65 of C. gattii (Cg) using optical microscopy andtransmission electron microscopy (TEM), analysis of melanization, TSA forfluconazole (FCZ) by E-Test® and time kill curves method (TK) for amphotericin B(AmB), molecular typing and mating-type (MAT). The study of new methodemployed the fungal load of 6 patients in their cerebrospinal fluid (CSF) samples atdiagnosis, 7th and 14th day of therapy for CSNC. The strains were classifiedaccording to molecular type and MAT, TSA using FCZ or AmB and drugcombination using AMB and 5-flucytosine (5FC) by chequerboard, and TK. Thefrequency of cell polymorphism was low (4%; 7/177), but never before reported inisolates of collection. The occurrence of polymorphism in blood isolates wasunprecedented, indicating the ease of dissemination of atypical cells into thebloodstream, as well as in CSF. All polymorphic phenotypes showed titan cells(100%; 7/7), and, at a lower percentage, formed pseudohyphae (43%; 3/7). Thephenomenon of polymorphism seems to be unique in Cn, since it was notobserved in Cg. The wall thickness of the titans cells presented the same variation(350 nm to 900 nm) compared to regular cells. Low melanization was observed in71.4% (5/7) of polymorphic isolates, two isolates showed both patterns ofmelanization. All isolates with regular cells showed high level of melanization. Lowsusceptibility (MIC, >8 mg/L) was observed in almost half of the isolates with titancells, indicating that polymorphism may be related to resistance to FCZ. The newmethod of TSA with individualized...


Assuntos
Antifúngicos , Criptococose , Cryptococcus neoformans , Genótipo , Parede Celular
9.
Braz. j. microbiol ; 45(4): 1409-1413, Oct.-Dec. 2014. ilus, graf
Artigo em Inglês | LILACS | ID: lil-741294

RESUMO

The antibacterial effect of α-terpineol from Cinnamomum longepaniculatum (Gamble) N. Chao leaf essential oils were studied with special reference to the mechanism of inhibiting the standard strain of Escherichia coli (CMCC (B) 44102) growth at ultrastructural level. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) and time-kill curves of α-terpineol were determined; Escherichia coli was treated with α-terpineol and observed under a transmission electron microscope. The MIC and MBC values of α-terpineol were all 0.78 µL/mL, and time-kill curves showed the concentration-dependent. Under the transmission electron microscopy (TEM), Escherichia coli exposed to MIC levels of α-terpineol exhibited decreased cell size and irregular cell shape, cell wall and cell membrane were ruptured, nucleus cytoplasm was reduced and nuclear area gathered aside. Results suggest that α-terpineol has excellent antibacterial activity and could induce morphological changes of Escherichia coli.


Assuntos
Antibacterianos/farmacologia , Cicloexenos/farmacologia , Escherichia coli/citologia , Escherichia coli/efeitos dos fármacos , Monoterpenos/farmacologia , Membrana Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Parede Celular/ultraestrutura , Cinnamomum/química , Cicloexenos/isolamento & purificação , Citoplasma/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Viabilidade Microbiana/efeitos dos fármacos , Monoterpenos/isolamento & purificação , Óleos Voláteis/isolamento & purificação , Folhas de Planta/química
10.
Braz. j. pharm. sci ; 50(3): 467-472, Jul-Sep/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-728699

RESUMO

The use of central venous catheters (CVC) and broad-spectrum antibacterials are among the main risk factors for the development of candidemia in patients admitted to intensive care units (ICU). It is known that some antibacterials increase the resistance of these yeasts to azole antifungals. Thus, the aim of this research was to determine whether yeast present in CVC colonizations previously exposed to cell-wall targeted antibacterials benefit from a reduction in susceptibility to fluconazole and voriconazole, facilitating their ability to form biofilms. Candida albicans, C. tropicalis, C. glabrata, C. parapsilosis and C. guilhermondii were seeded into antibacterial (cefepime, meropenem, vancomycin, and piperacillin-tazobactam) gradient plates produced in Mueller-Hinton Agar. The susceptibility to fluconazole and voriconazole and the biofilm formation of the yeasts were tested before and after exposure to the antibacterials. None of the antibacterials exerted a significant effect on the in vitro susceptibility of the yeasts to the antifungal agents or on their ability to form biofilms. These results suggest that increased candidemia in ICU patients is not attributable to possible alterations in the yeasts, but is more likely caused by a weakening of the patient's general condition after long exposure to infection.


O uso de cateter venoso central (CVC) e antibióticos de amplo espectro estão entre os principais fatores de risco para o desenvolvimento da candidemia em pacientes internados em unidades de terapia intensiva (UTI). É conhecido que alguns antibióticos aumentam a resistência das leveduras aos antifúngicos azólicos. Assim, o objetivo deste estudo foi avaliar se leveduras presentes em colonização de CVC expostas a antibióticos que atuam em parede celular se beneficiam de uma redução na suscetibilidade ao fluconazol e voriconazol e se obtêm maior capacidade de formar biofilme. Candida albicans, C. tropicalis, C. glabrata,C. parapsilosis e C. guilhermondii foram semeadas em placas de Mueller-Hinton Agar, com gradientes de antibióticos (cefepima, meropenem, vancomicina e piperacilina-tazobactam). A suscetibilidade e a formação de biofilme das leveduras foram testadas antes e após a exposição aos antibióticos. Nenhum dos antibióticos provocou alterações detectáveis in vitro sobre a suscetibilidade das leveduras aos antifúngicos ou à capacidade de formar biofilme. Estes resultados sugerem que o aumento da candidemia na UTI não seria atribuído a possíveis alterações provocadas nas leveduras e sim pelo enfraquecimento da condição geral do paciente após longa exposição à infecção.


Assuntos
Antibacterianos , Biofilmes/classificação , Candida/classificação , Parede Celular/classificação , Antifúngicos , Cateteres Venosos Centrais , Suscetibilidade a Doenças
11.
Arq. bras. med. vet. zootec ; 65(4): 1139-1148, Aug. 2013. graf, tab
Artigo em Português | LILACS | ID: lil-684473

RESUMO

Os efeitos da parede celular de Saccharomyces cerevisiae (PCSc) na dieta para frangos foram avaliados com base nos tratamentos: dieta referência com avilamicina (AV); dieta referência (DR); DR com 0,1% de PCSc (PCSc0,1); DR com 0,2% de PCSc (PCSc0,2); DR com 0,3% de PCSc (PCSc0,3). O delineamento foi o de blocos ao acaso, com cinco tratamentos e seis repetições de 10 aves, totalizando 300 frangos, machos. No período de nove a 21 dias de idade, o tratamento PCSc0,3 influenciou negativamente no ganho de peso (631g), e no período de 34 a 39 dias, o tratamento PCSc0,1 proporcionou melhor ganho de peso (461g) em relação ao tratamento com o antimicrobiano. O maior peso vivo ao abate, 2571g, foi obtido no tratamento PCSc0,1. Os pesos absolutos de sobrecoxa e coxa+sobrecoxa foram maiores nos tratamentos PCSc0,1 (290g e 560g) e PCSc0,2 (292g e 561g) e menores no tratamento PCSc0,3 (263g e 515g). Não houve influência na metabolizabilidade da ração e na contagem total de coliformes totais no íleo. Dietas com inclusão de até 0,2% de PCSc resultaram em índices produtivos adequados, podendo ser utilizadas como aditivo em dietas livres de antimicrobiano melhorador de desempenho sem o comprometimento do desempenho, características de carcaça, metabolizabilidade da ração e da contagem total de coliformes totais do íleo.


The effects of the yeast cell wall (Saccharomyces cerevisiae) (CWSc) in the diet of broiler chickens were evaluated through the following treatments: reference diet with avilamicin (AV); reference diet (RD); RD with 0.1% CWSc (CWSc0,1); RD with 0.2% CWSc (CWSc0,2); RD with 0.3% CWSc (CWSc0,3). The study design was randomized blocks, with five treatments and six replicates of 10 birds, totaling 300 male broilers. In the period from 9 to 21 days treatment CWSc0.3 had a negative influence on weight gain (631g) and from 34 to 39 days CWSc0.1 provided better weight gain (461g) compared to the treatment with the antimicrobial. The highest live weight value at slaughter, 2,571 grams, was obtained in treatment CWSc0.1. The absolute weights of drumstick and thigh+drumstick were higher in treatments CWSc0.1 (290g and 560g) and CWSc0.2 (292g and 561g) and were lower for CWSc0.3 (263g and 515g). There was no influence of the treatments on both the metabolizability and the total count of coliforms in the ileum. Diets until 0.2% of PCSc inclusion resulted in correct productive rates and they can be used as a ration growth promoter additive in antimicrobial free diets without damage on performance, carcass characteristics, organ weight, metabolizability of the diets and total coliform count in the ileum.


Assuntos
Animais , Dieta/métodos , Leveduras/patogenicidade , Parede Celular/parasitologia , Saccharomyces , Galinhas/classificação
12.
Gac. méd. Caracas ; 120(2): 107-114, abr.-jun. 2012. tab
Artigo em Espanhol | LILACS | ID: lil-679022

RESUMO

La fibra dietética o fibra alimentaria, forma parte de lo que se considera una dieta equilibrada o saludable. A pesar que la fibra alimentaria no se considera un nutriente, es un componente importante de la dieta diaria. La razón principal de su importancia, es que pasa por el sistema digestivo sin ser absorbida y este hecho fisiológico, trae beneficios a la salud. La fibra alimentaria, se considera como el material alimenticio particularmente de origen vegetal que no es hidrolizado por las enzimas secretadas por el tracto digestivo humano, pero, que puede ser fermentada en el intestino grueso por la microflora colónica. El grupo de enfermedades crónicas no transmisibles, incluye: obesidad, diabetes, enfermedades cardiovasculares y cerebrovasculares, la hipertensión arterial, el cáncer y problemas articulares. Estudios epidemiológicos, muestran el efecto beneficioso de la fibra en el tratamiento terapéutico en algunas de estas enfermedades crónicas


Dietary fiber or alimentary fiber, is part of what is considered a balanced or healthy diet. Although the alimentary fiber is not considered a nutrient, is an important component of the diet. The main reason for its importance is passing through the digestive system without being absorbed and this physiological fact is beneficial to health. The alimentary fiber is considered as particularly the food material of plant origin that is not hydrolyzed by enzymes secreted by the human digestive tract, but that can be fermented in the large intestine by colonic microflora. The group of chronic non-communicable diseases, include: obesity, diabetes, cardiovascular and cerebrovascular diseases, hypertension, cancer and joint problems. Epidemiological studies show the beneficial effect of fiber in the therapeutic treatment in some of these chronic diseases


Assuntos
Humanos , Masculino , Feminino , Diabetes Mellitus/metabolismo , Doença Crônica/terapia , Doenças Cardiovasculares/metabolismo , Fibras na Dieta/uso terapêutico , Obesidade/etiologia , Parede Celular/metabolismo , Compostos Orgânicos/administração & dosagem , Comportamentos Relacionados com a Saúde , Grupos Populacionais , Sistema Digestório/fisiopatologia
14.
Braz. j. microbiol ; 42(3): 992-1000, July-Sept. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-607529

RESUMO

Several antihistaminics possess antibacterial activity against a broad spectrum of bacteria. However, the exact mechanism of such activity was unclear. Hence, the aim of this study is to investigate their mechanism of antibacterial activity especially their effect upon the permeability of the bacterial cytoplasmic membrane. The effects of azelastine, cetirizine, cyproheptadine and diphenhydramine were studied using Gram-positive and Gram-negative multiresistant clinical isolates. Leakage of 260 and 280 nm UV-absorbing materials was detected upon treatment with the tested antihistaminics; indicative of membrane alteration. Using an artificial membrane model, cholesterol-free negatively-charged unilamellar liposomes, confirmed the effect of antihistaminics upon the membrane permeability both by showing an apparent membrane damage as observed microscopically and by detection of leakage of preloaded dye from the liposomes colorimatrically. Moreover, examination of the ultrastructure of cells treated with azelastine and cetirizine under the transmission electron microscope substantiated the detected abnormalities in the cell wall and membrane. Furthermore, the effect of pretreating certain isolates for both short and long periods with selected antihistaminics was followed by the viable count technique. Increased vulnerability towards further exposure to azelastine was observed in cells pretreated with azelastine for 2 days and those pretreated with azelastine or cetrizine for 30 days.


Assuntos
Humanos , Membrana Celular , Permeabilidade da Membrana Celular , Parede Celular , Citoplasma , Resistência Microbiana a Medicamentos , Antagonistas dos Receptores Histamínicos H1 , Lipossomas Unilamelares/análise , Lipossomas Unilamelares/farmacologia , Métodos , Técnicas
15.
Arq. bras. med. vet. zootec ; 63(4): 931-940, ago. 2011. tab
Artigo em Português | LILACS | ID: lil-599613

RESUMO

Foram estudados os efeitos da glutamina, dos ácidos graxos poli-insaturados e da parede celular de levedura (PCL) sobre a estrutura e ultraestrutura do intestino delgado e o desempenho de leitões. Foram utilizados 45 leitões, desmamados aos 21 dias de idade, para testar os seguintes tratamentos: T1 - dieta basal; T2 - dieta basal + 1 por cento de glutamina; T3 - dieta basal + 0,2 por cento de PCL; T4 - dieta basal + 5 por cento de óleo de peixe. Nos dias sete e 14 pós-desmame, foram abatidos cinco leitões de cada tratamento. Os aditivos testados não alteraram a altura e a densidade dos vilos nem a profundidade das criptas do intestino delgado. Foi observado efeito de idade, mostrando redução na altura e na densidade dos vilos e na profundidade das criptas após o desmame. No duodeno e jejuno, foram observados maiores valores de relação vilo:cripta, que aumentaram com a idade pós-desmame. Ocorreram redução da altura dos microvilos do duodeno aos sete dias e aumento da largura dos microvilos do jejuno aos 14 dias pós-desmame. A área de superfície apical dos enterócitos não foi alterada pelos fatores estudados. Os aditivos estudados não foram eficientes em prevenir a atrofia da mucosa intestinal do jejuno, ao não interferir na sua ultraestrutura. Os aditivos incluídos na dieta não influenciaram o desempenho dos leitões no pós-desmame.


The effects of glutamine, poliunsatured fatty acids and cellular wall of yeast (CWY) under the structure and ultra structure of the small gut and the performance of the piglets were studied. Forty five piglets weaned at 21 days were used to test the following treatments: T1 - basal diet; T2 - basal diet + 1 percent of glutamine; T3 - basal diet + 0,2 percent of CWY; T4 - basal diet + 5 percent of fish oil. At seven and 14 post weaning days, five piglets of each treatment were slaughtered. The height, density of villus and depth of small gut crypts were not altered by the inclusion of additives. The effect of age was observed, showing a reduction in the height and density of villus and depth of crypts after weaning. In duodenum and jejunum higher values were observed in the relation villus:crypt, which increased with the post wean age. There was a decrease in the height of microvillus of the duodenum at 7 days and an increase of the width of the microvillus of jejunum at 14 days after wean. The area of the apical surface of the enterocytes was not altered by the studied factors. The studied additives were not efficient to prevent the atrophy of the intestinal mucosa of the jejunum, since they did not interfere on its ultra structure. Piglet performance was not affected by the additives included in the diet.


Assuntos
Animais , Ácidos Graxos Insaturados/administração & dosagem , Parede Celular , Glutamina/administração & dosagem , Suínos/crescimento & desenvolvimento , Leveduras , Ração Animal , Mucosa Intestinal , Prebióticos
16.
Braz. j. microbiol ; 42(1): 114-125, Jan.-Mar. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-571382

RESUMO

The events involved in the structural interaction between the diazotrophic endophytic bacterium Herbaspirillum seropedicae, strain RAM10, labeled with green fluorescent protein, and pineapple plantlets 'Vitória' were evaluated by means of bright-field and fluorescence microscopy, combined with scanning electron microscopy for 28 days after inoculation. After 6 hours of inoculation, H. seropedicae was already adhered to the roots, colonizing mainly root hair surface and bases, followed by epidermal cell wall junctions. Bacteria adherence in the initial periods occurred mainly in the form of solitary cells and small aggregates with pleomorphic cells. Bacteria infection of root tissue occurred through the cavities caused by the disruption of epidermal cells during the emergence of lateral roots and the endophytic establishment by the colonization of intercellular spaces of the cortical parenchyma. Moreover, within 1 day after inoculation the bacteria were colonizing the shoots. In this region, the preferred sites of epiphytic colonization were epidermal cell wall junctions, peltate scutiform trichomes and non-glandular trichomes. Subsequently, the bacteria occupied the outer periclinal walls of epidermal cells and stomata. The penetration into the shoot occurred passively through stoma aperture followed by the endophytic establishment on the substomatal chambers and spread to the intercellular spaces of spongy chlorenchyma. After 21 days of inoculation, bacterial biofilm were seen at the root hair base and on epidermal cell wall surface of root and leaf, also confirming the epiphytic nature of H. seropedicae.


Assuntos
Ananas/crescimento & desenvolvimento , Ananas/genética , Biofilmes , Parede Celular , Fixação de Nitrogênio/genética , Herbaspirillum/crescimento & desenvolvimento , Herbaspirillum/isolamento & purificação , Técnicas In Vitro , Microscopia Eletrônica , Proteínas de Fluorescência Verde/análise , Técnicas Genéticas , Métodos , Microscopia de Fluorescência , Plantas
17.
Braz. j. microbiol ; 42(1): 216-224, Jan.-Mar. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-571392

RESUMO

The goals of this study were to evaluate the effectiveness of Cuminum cyminum, Ziziphora clinopodioides and Nigella sativa essential oils to inhibit the growth of Aspergillus fumigatus and A. flavus and to evoke ultrastructural changes. The fungi were cultured into RPMI 1640 media in the presence of oils at concentrations of 8, 6, 5, 4, 3, 2, 1.5, 1.25, 1, 0.75 and 0.5 mg/ml in broth microdilution and 2, 1.5, 1 and 0.5 mg/ml in broth macrodilution methods with shaking for 48 h at 28ºC. Conidial and mycelial samples exposed to 0.25, 0.5, 1, 1.5 and 2 mg essential oils/ml for 5 days in 2 percent yeast extract granulated plus 15 percent Saccharose media were processed for transmission electron microscopy (TEM). Based on broth dilution methods, C. cyminum and to a lesser extent Z. clinopodioides oils exhibited the strongest activity against A. fumigatus and A. flavus with MIC90 ranging from 0.25 to 1.5 mg/ml, while the oil from N. sativa exhibited relatively moderate activity against two above fungi with MIC90 ranging from 1.5 to 2 mg/ml. The main changes observed by TEM were in the cell wall, plasma membrane and membranous organelles; in particular, in the nuclei and mitochondria. These modifications in fungal structure were associated with the interference of the essential oils with the enzymes responsible for cell wall synthesis, which disturbed normal growth. Moreover, the essential oils caused high vacuolation of the cytoplasm, detachment of fibrillar layer of cell wall, plasma membrane disruption and disorganization of the nuclear and mitochondrial structures. Aspergillus fumigatus and A. flavus growth inhibition induced by these oils were found to be well-correlated with subsequent morphological changes of the fungi exposed to different fungistatic concentrations of the oils. Our results show the anti-Aspergillus activities of C. cyminum, Z. clinopodioides and N. sativa essential oils, which strengthens the potential use of these substances as anti-mould in the future.


Assuntos
Aspergillus flavus/crescimento & desenvolvimento , Aspergillus fumigatus/crescimento & desenvolvimento , Parede Celular , Meios de Cultura , Cuminum/crescimento & desenvolvimento , Ativação Enzimática , Óleos Voláteis/análise , Eficácia , Métodos , Microscopia Eletrônica , Preparações de Plantas , Técnicas
18.
Mem. Inst. Oswaldo Cruz ; 106(2): 248-250, Mar. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-583953

RESUMO

We utilized two-dimensional gel electrophoresis and immunoblotting (2D-immunoblotting) with anti-Sporothrix schenckii antibodies to identify antigenic proteins in cell wall preparations obtained from the mycelial and yeast-like morphologies of the fungus. Results showed that a 70-kDa glycoprotein (Gp70) was the major antigen detected in the cell wall of both morphologies and that a 60-kDa glycoprotein was present only in yeast-like cells. In addition to the Gp70, the wall from filament cells showed four proteins with molecular weights of 48, 55, 66 and 67 kDa, some of which exhibited several isoforms. To our knowledge, this is the first 2D-immunoblotting analysis of the S. schenckii cell wall.


Assuntos
Animais , Masculino , Coelhos , Antígenos de Fungos , Parede Celular/imunologia , Glicoproteínas de Membrana , Sporothrix/imunologia , Eletroforese em Gel Bidimensional , Immunoblotting , Sporothrix
19.
Rio de Janeiro; s.n; 2011. 137 p. ilus, graf.
Tese em Português | LILACS | ID: lil-668610

RESUMO

Aspergillus fumigatus é o principal agente etiológico da aspergilose invasiva, infecção fúngica oportunista com altas taxas de mortalidade afetando, principalmente, pacientes com neutropenia profunda e prolongada. Durante o processo de invasão e disseminação características desta infecção sistêmica, os conídios do fungo inalados e não eliminados pelas células do sistema imune inato diferenciam-se em hifas que, por sua vez, são angioinvasivas. Pouco se conhece sobre as moléculas da parede celular envolvidas na patogênese do A. fumigatus e/ou secretadas por este patógeno. Neste contexto, este trabalho procura ampliar o entendimento desta doença através do estudo de proteínas diferencialmente expressas na superfície de A. fumigatus durante a morfogênese. Foi utilizada uma abordagem proteômica e foram estudados extratos de superfície de células de A. fumigatus em diferentes estágios durante o processo de filamentação. Estas células foram denominadas, de acordo com o tempo de cultivo e a morfologia, como: TG6h (tubo germinativo), H12h ou H72h (hifas). As proteínas de superfície celular foram extraídas, a partir de células intactas, por tatamento brando com o agente redutor DTT (ditiotreitol). Observou-se que o perfil funcional das proteínas expressas por H12h e H72h foi similar, com exceç~çao de proteínas relacionadas à resposta ao estresse, enquanto o perfil para TG6h apresentou diferenças significativas para vários grupos funcionais de proteínas quando comparado às hifas. Desta forma, foram realizados experimentos de proteômica diferencial entre tubo germinativo (TG6h) e a hifa madura (H72h), pela técnica de DIGE (differential gel electrophoresis). Os resultados revelaram que entre as proteínas diferencialmente expressas, aquelas relacionadas às vias de biossíntese e outras denominadas multifuncionais encontram-se superexpressas em TG6h. Em relação às proteínas de resposta a estresse, observou-se que algumas HSPs eram mais expressas neste morfotipo...


Aspergillus fumigatus is the main etiologic agent of invasive aspergillosis (IA), a opportunistic a life-threatening disease for immunocompromised hosts, especially those with acute and prolonged neutropenia. During the invasion and dissemination, which occurs in this systemic infection, the A. fumigatus conidia, after its inhalation, germinates into angioinvasive hyphae in case the innate immune response fails in eliminate these cells. Little is known about the cell wall molecules and/or the secreted proteins involved on the A. fumigatus pathogenesis, at this context the present work aims to amplify the knowledge about the aspergillosis by studying the differentially surface proteins of A. fumigatus during the filamentation process. These cells were denominated according to their morphology and their growtn time as: TG6h (germ tubes), H12h and H72h (hyphae). The surface proteins were mildly extracted from intact cells using the reducing agent DTT (dithiothreitol). The functional profile of the H12h and H72h were similar except for the stress response proteins, while the TG6h presented significant differences for several functional groups. On this base, the DIGE (differential gel electrophoresis) was performed using the surface extracted proteins of the germ tubes (TG6h) and mature hyphae (H72h) cells. The results indicate that multiple functional proteins and proteins related to the biosynthesis pathways were overexpressed at TG6h. Some stress response proteins as the HSPs were overexpressed on this morphotype while the MnSOD, oxidative stress responsive protein, was most abundant at the hyphae. PhiA, an integrant protein of the cell wall, was the only protein with a secretion signal sequence. All other proteins identified on the cell surface lack an identifiable secretion sign, and are denominated atypical proteins. The plasma membrane integrity was verified after the mild extraction using DTT, and also the biotinylation of the cell extracted proteins...


Assuntos
Aspergillus fumigatus/patogenicidade , Proteínas Fúngicas/análise , Ditiotreitol , Eletroforese em Gel Diferencial Bidimensional/métodos , Hifas/fisiologia , Proteínas de Membrana , Parede Celular , Proteoma/análise , Proteômica/métodos
20.
Mem. Inst. Oswaldo Cruz ; 104(3): 492-496, May 2009.
Artigo em Inglês | LILACS | ID: lil-517015

RESUMO

Histoplasma capsulatum is an intracellular fungal pathogen that causes respiratory and systemic disease by proliferating within phagocytic cells. The binding of H. capsulatum to phagocytes may be mediated by the pathogen's cell wall carbohydrates, glucans, which consist of glucose homo and hetero-polymers and whose glycosydic linkage types differ between the yeast and mycelial phases. The ±-1,3-glucan is considered relevant for H. capsulatum virulence, whereas the ²-1,3-glucan is antigenic and participates in the modulation of the host immune response. H. capsulatum cell wall components with lectin-like activity seem to interact with the host cell surface, while host membrane lectin-like receptors can recognize a particular fungal carbohydrate ligand. This review emphasizes the relevance of the main H. capsulatum and host carbohydrate-driven interactions that allow for binding and internalization of the fungal cell into phagocytes and its subsequent avoidance of intracellular elimination.


Assuntos
Animais , Humanos , Carboidratos/imunologia , Parede Celular/química , Histoplasma/química , Histoplasmose/imunologia , Parede Celular/imunologia , Interações Hospedeiro-Parasita , Histoplasma/patogenicidade , Histoplasma/fisiologia , Fatores Imunológicos/imunologia
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