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Search Results: 1 - 10 of 16891 matches for " Marcio Jose Po?as-Fonseca "
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An Acidic Thermostable Recombinant Aspergillus nidulans Endoglucanase Is Active towards Distinct Agriculture Residues
Eveline Queiroz de Pinho Tavares,Marciano Regis Rubini,Thiago Machado Mello-de-Sousa,Gilvan Caetano Duarte,Fabrícia Paula de Faria,Edivaldo Ximenes Ferreira Filho,Cynthia Maria Kyaw,Ildinete Silva-Pereira,Marcio Jose Poas-Fonseca
Enzyme Research , 2013, DOI: 10.1155/2013/287343
Abstract: Aspergillus nidulans is poorly exploited as a source of enzymes for lignocellulosic residues degradation for biotechnological purposes. This work describes the A. nidulans Endoglucanase A heterologous expression in Pichia pastoris, the purification and biochemical characterization of the recombinant enzyme. Active recombinant endoglucanase A (rEG A) was efficiently secreted as a 35?kDa protein which was purified through a two-step chromatography procedure. The highest enzyme activity was detected at C/pH 4. rEG A retained 100% of activity when incubated at 45 and C for 72?h. Purified rEG A kinetic parameters towards CMC were determined as ?mg/mL, ?mmol/min, and 55.8?IU (international units)/mg specific activity. Recombinant P. pastoris supernatant presented hydrolytic activity towards lignocellulosic residues such as banana stalk, sugarcane bagasse, soybean residues, and corn straw. These data indicate that rEG A is suitable for plant biomass conversion into products of commercial importance, such as second-generation fuel ethanol. 1. Introduction One of the major challenges of modern society is to promote economic growth in a sustainable model. Global demands of energy consumption stimulate the research on alternative fuels, aiming the reduction of the dependence on nonrenewable energy sources. For some decades now, Brazil and the USA have successfully produced bioethanol from sugarcane and corn, respectively. Nonetheless, plant biomass generated by extensive cultures, and which is not totally converted into useful by-products such as fertilizers and animal feed, tends to accumulate and cause environmental problems. Numerous efforts have been made in order to develop biotechnological routes to produce the so-called second-generation bioethanol from agriculture residues such as corn stover, rice straw, sorghum bagasse, corncobs, wheat bran, wheat straw, and sugarcane bagasse. The limiting step of this process is the availability of low-cost efficient enzymes to convert lignocellulose into fermentable glucose units. Filamentous fungi can produce and secrete enzymes which efficiently degrade cellulose, a linear polymer of glucopyranose units connected by β-1,4 bonds, to oligosaccharides and glucose. Based on model organisms from the genera Trichoderma and Phanerochaete, fungi cellulolytic enzymes acting in synergism have been classified as (1) endoglucanases or endo-β-1,4-glucanases (EC 3.2.1.4), responsible for the random attack of internal glycosidic bonds of the cellulose amorphous region, generating oligosaccharides of various sizes and new chain ends
From an electrophoretic mobility shift assay to isolated transcription factors: a fast genomic-proteomic approach
Astrid R Mach-Aigner, Karin Grosstessner-Hain, Marcio J Poas-Fonseca, Karl Mechtler, Robert L Mach
BMC Genomics , 2010, DOI: 10.1186/1471-2164-11-644
Abstract: We used streptavidin affinity chromatography to isolate the Xylanase promoter-binding protein 1 (Xpp1). The optimal conditions and templates for the chromatography step were chosen according to the results of an electrophoretic mobility shift assay performed under repressing conditions, which yielded a DNA-protein complex specific to the AGAA-box (the previously identified, tetranucleotide cis-acting element). After isolating AGAA-box binding proteins, the eluted proteins were identified with Nano-HPLC/tandem MS-coupled detection. We compared the identified peptides to sequences in the H. jecorina genome and predicted in silico the function and DNA-binding ability of the identified proteins. With the results from these analyses, we eliminated all but three candidate proteins. We verified the transcription of these candidates and tested their ability to specifically bind the AGAA-box. In the end, only one candidate protein remained. We generated this protein with in vitro translation and used an EMSA to demonstrate the existence of an AGAA-box-specific protein-DNA complex. We found that the expression of this gene is elevated under repressing conditions relative to de-repressing or inducing conditions.We identified a putative transcription factor that is potentially involved in repressing xylanase 2 expression. We also identified two additional potential regulatory proteins that bind to the xyn2 promoter. Thus, we succeeded in identifying novel, putative transcription factors for the regulation of xylanase expression in H. jecorina.Hypocrea jecorina (anamorph Trichoderma reesei, [1]) is an abundant filamentous ascomycete. H. jecorina breaks down polysaccharides with a variety of hydrolytic enzymes that act synergistically [2,3]. Due to the high secretory capacity of this fungus (up to 100 g/L, [4]), H. jecorina has gained industrial importance and is employed both in the fermentative production of native extracellular enzymes and heterologous protein production. The
Anticlastogenic potential and antioxidant effects of an aqueous extract of pulp from the pequi tree (Caryocar brasiliense Camb)
Khouri, Juliana;Resck, Inês S.;Poas-Fonseca, Marcio;Sousa, Thiago M.M.;Pereira, Luciana O.;Oliveira, Adriano B.B.;Grisolia, Cesar K.;
Genetics and Molecular Biology , 2007, DOI: 10.1590/S1415-47572007000300024
Abstract: the effectiveness of an aqueous extract of caryocar brasiliense (caryocaraceae) camb pulp, popularly known in brazil as pequi, against clastogenicity induced by cyclophosphamide and bleomycin was evaluated using an in vivo mouse bone marrow cell micronuclei test, an in vitro chinese hamster ovary cell (cho-k1) chromosome aberration test and an in vitro antioxidant assay based on the oxidative damage to 2-deoxy-d-ribose (2-dr) induced by hydroxyl radicals (?oh) generated by the reaction between ascorbic acid and (fe iii)-edta. in mouse bone marrow cells the extract showed a protective effect against micronuclei induced by cyclophosphamide and bleomycin but did not interfere with polychromatic bone marrow erythrocyte proliferation, except when the mice had been treated with the highest dose of cyclophosphamide. when cho-k1 cells were pretreated by adding 0.01, 0.05 or 0.1 ml of extract per ml of cell culture medium 24 or 48 h before bleomycin or cyclophosphamide there was a protective effect against chromosome breaks and a significant decrease in the mitotic index (a measure of cytotoxicity) of the cho-k1 cells. the extract also had a protective effect against oxidative hydroxyl radical damage to 2-dr. this study suggests that c. brasiliense pulp aqueous extract has anticlastogenic potential, possibly due to its antioxidative properties.
Forma??o do fonoaudiólogo no município de Salvador e consolida??o do SUS
Lemos,Marcio; Bazzo,Leda Maria Fonseca;
Ciência & Saúde Coletiva , 2010, DOI: 10.1590/S1413-81232010000500030
Abstract: the human resources in health (hrh) academic field is recognized as a critical area, which is part of the reorientation process in the health sector. the elaboration of the unified health system (sus) represents challenges to the academic field process, especially regarding new careers such as speech-language pathology. this is related with the lack of awareness regarding collective health and the past history that strengthened the public health policies in brazil. yet, the powerful influence of the service model to the spontaneous demand and reabilitation therapy plays another key role in the aspect. the aim was to analyze the academic field of the speech-language pathology profile in the city of salvador, bahia state. documental analysis and coordinator interviews were used to investigate how the public area is characterized in 3 modules. it was noticed little adhesion of the upper level institutions to the legislation of the field; lack of contact between graduating students and collective health, and a teaching-service disconnection. the graduation of the speech therapist was shown incipient regarding sus's consolidation. identifying challenges and opportunities of changes in hrh formation in upper level institutions may lead to better levels of aid to the population, quality of education and expansion of theoretical and practical models of knowledge.
Canonical Modeling of the Multi-Scale Regulation of the Heat Stress Response in Yeast
Luis L. Fonseca,Po-Wei Chen,Eberhard O. Voit
Metabolites , 2012, DOI: 10.3390/metabo2010221
Abstract: Heat is one of the most fundamental and ancient environmental stresses, and response mechanisms are found in prokaryotes and shared among most eukaryotes. In the budding yeast Saccharomyces cerevisiae, the heat stress response involves coordinated changes at all biological levels, from gene expression to protein and metabolite abundances, and to temporary adjustments in physiology. Due to its integrative multi-level-multi-scale nature, heat adaptation constitutes a complex dynamic process, which has forced most experimental and modeling analyses in the past to focus on just one or a few of its aspects. Here we review the basic components of the heat stress response in yeast and outline what has been done, and what needs to be done, to merge the available information into computational structures that permit comprehensive diagnostics, interrogation, and interpretation. We illustrate the process in particular with the coordination of two metabolic responses, namely the dramatic accumulation of the protective disaccharide trehalose and the substantial change in the profile of sphingolipids, which in turn affect gene expression. The proposed methods primarily use differential equations in the canonical modeling framework of Biochemical Systems Theory (BST), which permits the relatively easy construction of coarse, initial models even in systems that are incompletely characterized.
Aminoácidos livres do feij?o 60 dias (Phaseolus vulgaris L.)
Arzolla, Jose D.P.;Fonseca, Homero;
Anais da Escola Superior de Agricultura Luiz de Queiroz , 1970, DOI: 10.1590/S0071-12761970000100015
Abstract: free amino acids of the new 60 days beans variety (phaseolus vulgaris l.) were studied by two dimensional ascending paper chromatography with the following pair of solvents: 1) phenol-water, 8:2 (v/v); 2) butanol-acetic acid-water , 4:1:1 (v/v). the amino acids identified and measured in the extracts were: aspartic acid, glutamic acid, lysine, serine, asparagine, glycine, threonine, alanine, glutamine, histidine, gama amino-butyric acid, arginine, methionine, valine and leucine. determinations were made by elution of the spots followed by colorimetry. the more abundant amino acids were lysine, glutamic acid and aspartic acid.
Ocorrência e dosagem de a?ucares em algumas variedades brasileiras de feij?o (Phaseolus vulgaris L.)
Fonseca, Homero;Arzolla, Jose D.P.;
Anais da Escola Superior de Agricultura Luiz de Queiroz , 1970, DOI: 10.1590/S0071-12761970000100016
Abstract: sugars present in some brazilian varieties of common beans (phaseolus vulgaris l.) were studied by two-dimension paper chromatography with the following pair of solvente: 1) phenol-water-amonia, 80: 20: 0,5 (w/v/v/ and 2) butanol-acetic acid-water, 40: 10: 5 (v/v). determinations were made by elution of the spots followed by colorimetry. the sugars identified and measured were raffinose, sucrose, melibiose, glucose and fructose. the more abundant sugars were fructose and glucose.
Estudio comparativo de equivalentes farmacéuticos de ibuprofeno en hospitales públicos de El Salvador
Jose Batres,Kenneth Fernández,Federico Fonseca
CIMEL. Ciencia e Investigación Médica Estudiantil Latinoamericana , 2003,
Abstract:
Identification of the Type of Strategic Policy for Sustainable Development on the Basis of Territorial Characterization. A Case Study in Canton Ba?os de Agua Santa, Tungurahua, Ecuador  [PDF]
Jose Fabian Fonseca Vasconez, Andrea del Pilar Ramirez Casco, Mario Alfonso Arellano Diaz, Xavier Sulca Guale
Theoretical Economics Letters (TEL) , 2017, DOI: 10.4236/tel.2017.75104
Abstract: This study was carried out in Banos de Agua Santa, Province of Tungurahua-Ecuador; From the time of Spanish colonization to the present day, the failure to implement sustainable development policies has led to the decline of some economic activities and has driven tourism as the main source of income without structured sustainable guidelines with established planning for which becomes a fundamental alternative axis, generating the depletion of tourism resources and territorial disorder, the product of an imposing mercantilist system that guides competitiveness in an indiscriminate way. In correspondence the objective was to identify the type of strategic policy for the sustained development of the tourist destination referred to. Methodologically the study uses theoretical methods such as analysis and synthesis, inductive-deductive, historical-logical, others of the empirical level, among which we can cite the criterion of experts, matrices of analysis such as: external factor evaluation (EFE), evaluation of Internal factors (EFI), SWOT analysis, strategic evaluation and position of action (PEEA) and descriptive statistics. The results obtained were the determination of the present and future incidence of economic activities in the territory under study and the projection of the type of strategic policy for sustainable and responsible management of natural, cultural, socio-productive resources, preventing different Economic cycles, through the evaluation of their productive factors.
Molecular discrimination of pouched four-eyed opossums from the Mamirauá Reserve in the Brazilian Amazon
Nunes, Cláudia;Ayres, Jose Marcio;Sampaio, Iracilda;Schneider, Horacio;
Genetics and Molecular Biology , 2006, DOI: 10.1590/S1415-47572006000200015
Abstract: previous cytochrome b (cytb) mtdna studies have suggested four species for the opossum genus philander (four-eyed opossums), three (p. mcilhennyi, p. andersoni and p. opossum) from the amazon and one (p. frenata) from the brazilian atlantic forest. during a faunal survey nine specimens of philander sp. and four of didelphis marsupialis were collected in the mamirauá sustainable reserve, amazonas state, brazil. preliminary analyses based on morphology and geographical distributions were not conclusive, suggesting that philander specimens could belong to either p. andersoni or p. opossum. in order to elucidate the relationship of this taxon to the remaining amazonian taxa, seven philander and two didelphis specimens animals were sequenced for the cytb mtdna gene and compared to other previously studied taxa. the maximum likelihood (ml), neighbor-joining (nj) and maximum parsimony (mp) consensus bootstrap trees depicted six groups: didelphis., p. frenata, p andersoni, p. mcilhennyi, p.o. opossum and philander sp. and philander canus in a common assemblage supported by significant bootstrap values, suggesting that the philander sp. from mamiraua in fact belongs to the species philander canus.
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