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Search Results: 1 - 10 of 9430 matches for " Augusto Schrank "
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Optimal Conditions for Continuous Immobilization of Pseudozyma hubeiensis (Strain HB85A) Lipase by Adsorption in a Packed-Bed Reactor by Response Surface Methodology
Roberta Bussamara,Luciane Dall'Agnol,Augusto Schrank,Kátia Flávia Fernandes,Marilene Henning Vainstein
Enzyme Research , 2012, DOI: 10.1155/2012/329178
Abstract: This study aimed to develop an optimal continuous process for lipase immobilization in a bed reactor in order to investigate the possibility of large-scale production. An extracellular lipase of Pseudozyma hubeiensis (strain HB85A) was immobilized by adsorption onto a polystyrene-divinylbenzene support. Furthermore, response surface methodology (RSM) was employed to optimize enzyme immobilization and evaluate the optimum temperature and pH for free and immobilized enzyme. The optimal immobilization conditions observed were 150?min incubation time, pH 4.76, and an enzyme/support ratio of 1282?U/g support. Optimal activity temperature for free and immobilized enzyme was found to be 68°C and 52°C, respectively. Optimal activity pH for free and immobilized lipase was pH 4.6 and 6.0, respectively. Lipase immobilization resulted in improved enzyme stability in the presence of nonionic detergents, at high temperatures, at acidic and neutral pH, and at high concentrations of organic solvents such as 2-propanol, methanol, and acetone. 1. Introduction Biocatalyst enzymes play an important role in biotechnological applications due to their extreme versatility with respect to substrate specificity and stereoselectivity and exhibit many other features that render their use advantageous when compared to conventional chemical catalysts. As an example, fat and oil hydrolysis using NaOH as a catalyst requires high pressure and temperature to achieve high efficiency (97-98%); in contrast, the same process can be carried out effectively at normal temperature and pressure using lipases, with significant decrease in wastewater production. Lipases (triacylglycerol acylhydrolase; EC catalyze the hydrolysis of triglycerides to glycerol and fatty acids, as well as a variety of reactions in nonaqueous medium (e.g., transesterification, esterification, and interesterification). Such enzymatic properties allow a series of biotransformation reactions that lead to multiple industrial applications in foods, flavors, pharmaceuticals, detergent formulation, oil/fat degradation, cosmetics, and environmental remediation [1–4]. However, soluble enzymes usually exhibit lower stability than chemical catalysts and often cannot be recovered and reused. This severely hinders their application in practice. Nevertheless, this problem can be overcome by enzyme immobilization, which enhances thermal and operational stabilities, ease of handling, and prevention of aggregation and autolysis. Besides, immobilized lipases (IE) on solid support allow recoverability and reuse thus significantly
Comparative genome analysis of proteases, oligopeptide uptake and secretion systems in Mycoplasma spp
Staats, Charley Christian;Boldo, Juliano;Broetto, Leonardo;Vainstein, Marilene;Schrank, Augusto;
Genetics and Molecular Biology , 2007, DOI: 10.1590/S1415-47572007000200009
Abstract: mycoplasmas are very fastidious in their nutritional requirements for in vitro growth and have limited biosynthetic capacity, a reflection of their reduced genomes. as a result, these bacteria depend upon external metabolites for nutrition and growth and have developed dependence on their hosts for survival and maintenance. protein degradation and peptide importation play an important role in mycoplasma spp. nutrition, and proteases can play a role in host adaptation and pathogenicity. here, we present a general survey on the genes involved in protein degradation, secretion and importation, comparing all available mollicute genomes.
Fungal zinc metabolism and its connections to virulence
Charley C. Staats,Lívia Kmetzsch,Augusto Schrank,Marilene H. Vainstein
Frontiers in Cellular and Infection Microbiology , 2013, DOI: 10.3389/fcimb.2013.00065
Abstract: Zinc is a ubiquitous metal in all life forms, as it is a structural component of the almost 10% of eukaryotic proteins, which are called zinc-binding proteins. In zinc-limiting conditions such as those found during infection, pathogenic fungi activate the expression of several systems to enhance the uptake of zinc. These systems include ZIP transporters (solute carrier 39 family) and secreted zincophores, which are proteins that are able to chelate zinc. The expression of some fungal zinc uptake systems are regulated by a master regulator (Zap1), first characterized in the yeast Saccharomyces cerevisiae. In this review, we highlight features of zinc uptake and metabolism in human fungal pathogens and aspects of the relationship between proper zinc metabolism and the expression of virulence factors and adaptation to the host habitat.
Síndrome de Cushing por uso abusivo de descongestionante nasal contendo dexametasona: Relato de caso
Caldas, Dayse;Schrank, Yolanda;
Revista Brasileira de Otorrinolaringologia , 2001, DOI: 10.1590/S0034-72992001000600018
Abstract: glucocorticoids have been largely used in the clinical practice since the early 1950s. while unwanted side effects related to its oral or parenteral use are well known, there are not many reports about such effects when glycocorticoids were used topically. we relate the case of a sixteen-year-old boy with allergic rhinitis who developed exogenous cushing syndrome after abusive use of a nasal spray containing dexamethasone in a daily dose varying from 0.5-0.7mg during 4 years. once the diagnosis of exogenous cushing syndrome was established, the spray containing dexamethasone was substituted by another one without steroids associated with the prescription of dexamethasone tablets in progressively lower doses. about 3 month later, when complete restoration of the hypothalamic-pituitary-adrenal axis was observed, the tablets were discontinued. we would like to emphasize the importance of a strict follow-up of all patients with chronic use of any drug containing glycocorticoids; it is recommended in some cases to determine urinary free or plasmatic cortisol after the new low-dose (1mcg) acth stimulation test, in order to come to the diagnosis of incipient adrenal insufficiency, which could offer some danger in the presence of mild to moderate stress. since the possibility of severe systemic side effects remains with the use of nasal steroids, we should whenever feasible prefer the use of glycocorticoids with lower bioavailability and emphasize the importance of respecting the dose and the time prescribed.
O centro de Aten??o Psicossocial e as estratégias para inser??o da família
Schrank, Guisela;Olschowsky, Agnes;
Revista da Escola de Enfermagem da USP , 2008, DOI: 10.1590/S0080-62342008000100017
Abstract: this research has the objective of identifying the mental health activities developed at centers of psycho-social attention (capss) directed to the family in the care of individuals in psychological suffering. it is a descriptive, analytic survey of the case study type with a qualitative approach. data collection was carried out through observation and semi-structured interviews with professionals of a caps. the results showed that the work at a caps becomes successful only when there is family partnership and participation. individual sessions, family groups, active searches, home visits and workshops are strategies used at capss for the effective insertion of the family. in this partnership, bonding appears as essential in the construction of less suffering and less stigmatized ways of psychical suffering.
Síndrome de Cushing por uso abusivo de descongestionante nasal contendo dexametasona: Relato de caso
Caldas Dayse,Schrank Yolanda
Revista Brasileira de Otorrinolaringologia , 2001,
Abstract: Os glicocorticóides têm sido largamente utilizados na prática clínica desde os princípios de 1950. Enquanto s o bem conhecidos os efeitos adversos relacionados ao seu uso oral ou parenteral, n o existem muitos relatos na literatura sobre efeitos adversos relacionados ao seu uso tópico. Relatamos o caso clínico de um rapaz de 16 anos com rinite alérgica que desenvolveu síndrome de Cushing exógena por uso abusivo de descongestionante nasal à base de dexametasona numa dose diária que variava de 0,5-0,7mg durante um período de 4 anos. O desmame do glicocorticóide foi iniciado substituindo-se o descongestionante em uso por outro sem glicocorticóide associado a doses progressivamente decrescentes de dexametasona administrada via oral, medica o esta que foi definitivamente suspensa 3 meses após o início do desmame - época na qual foi constatada recupera o do eixo hipotálamo-hipófise-adrenal. Chamamos a aten o para a importancia do acompanhamento criterioso dos pacientes em uso, a longo prazo, de toda e qualquer medica o que contenha glicocorticóide, eventualmente até com monitoriza o mais rigorosa através da determina o do cortisol livre urinário ou do cortisol plasmático após teste de estímulo com o ACTH dose baixa (1mcg), permitindo assim o diagnóstico de insuficiência adrenal, mesmo que incipiente, mas que na presen a de stress leve a moderado poderia oferecer risco de vida. Diante da possibilidade de severos efeitos colaterais sistêmicos mesmo quando utilizados esteróides nasais, devemos sempre que possível dar preferência aos glicocorticóides de menor biodisponibilidade e insistir junto ao paciente para que seja respeitada a dose assim como o tempo de uso prescrito.
Zap1 Regulates Zinc Homeostasis and Modulates Virulence in Cryptococcus gattii
Rafael de Oliveira Schneider, Natully de Souza Süffert Foga?a, Lívia Kmetzsch, Augusto Schrank, Marilene Henning Vainstein, Charley Christian Staats
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0043773
Abstract: Zinc homeostasis is essential for fungal growth, as this metal is a critical structural component of several proteins, including transcription factors. The fungal pathogen Cryptococcus gattii obtains zinc from the stringent zinc-limiting milieu of the host during the infection process. To characterize the zinc metabolism in C. gattii and its relationship to fungal virulence, the zinc finger protein Zap1 was functionally characterized. The C. gattii ZAP1 gene is an ortholog of the master regulatory genes zafA and ZAP1 that are found in Aspergillus fumigatus and Saccharomyces cerevisiae, respectively. There is some evidence to support an association between Zap1 and zinc metabolism in C. gattii: (i) ZAP1 expression is highly induced during zinc deprivation, (ii) ZAP1 knockouts demonstrate impaired growth in zinc-limiting conditions, (iii) Zap1 regulates the expression of ZIP zinc transporters and distinct zinc-binding proteins and (iv) Zap1 regulates the labile pool of intracellular zinc. In addition, the deletion of ZAP1 reduces C. gattii virulence in a murine model of cryptococcosis infection. Based on these observations, we postulate that proper zinc metabolism plays a crucial role in cryptococcal virulence.
Molecular characterization of Rhodococcus equi isolates of horse breeding farms from an endemic region in South of Brazil by multiplex PCR
Krewer, Cristina da Costa;Spricigo, Dênis Augusto;Botton, S?nia de Avila;Costa, Mateus Matiuzzi da;Schrank, Irene;Vargas, Agueda Castagna de;
Brazilian Journal of Microbiology , 2008, DOI: 10.1590/S1517-83822008000100036
Abstract: rhodococcus equi is a gram-positive coco-bacillus and an intracellular opportunistic pathogen which causes pneumonia in foals. it is widely detected in environment and has been isolated from several sources, as soil, feces and gut from health and sick foals. the goal of this study was to characterize the epidemiological status (endemic, sporadic or no infection) of horse breeding farms from bage county in south of brazil, using a multiplex pcr. one hundred and eighteen r. equi isolates were identified by biochemical tests and submitted to a specie-specific and vapa multiplex pcr. these isolates were obtained from: three farms where the r. equi infection has been noticed, two farms where the disease has been not reported and one farm where the disease is frequent. all clinical isolates from horse breeding farms where the disease is endemic and/or sporadic were vapa-positive. none environmental isolates were vapa-positive. in three horse breeding farms with sporadic r. equi infection, 11.54% of the isolates from adult horse feces were vapa-positive. the multiplex pcr technique has proven to be effective for the molecular and epidemiological characterization of the r. equi isolates in horse breeding farms. an important finding in this study was the isolation of vapa-positive r. equi from adult horse feces, which is an evidence for other routes of dissemination of this pathogen in the farms.
CAPTURING STATESTRENGTH: EXPERIMENTAL AND ECONOMETRIC APPROACHES Capturando la fortaleza del Estado: Aproximaciones econométricas y experimentales
Revista de Ciencia Política , 2012,
Abstract: While almost all definitions of the state and state capacity (or stateness) derive at their core from a Weberian emphasis on the characteristics of institutions, the dominant measures of this concept rely instead on subjective, perceptions-based indicators. We propose an alternative strategy rooted in direct experimentation and econometric modeling to develop objective measures of the strength of state institutions, both for a contemporary cross section, but also (for the latter) for cross-time historical data essential for tracking the development of institutions. Aunque casi todas las definiciones de Estado y capacidad estatal (o estatalidad) derivan del énfasis weberiano en las características de las instituciones, las mediciones de este concepto que predominan descansan, sin embargo, en indicadores subjetivos basados en percepciones. Este trabajo propone una estrategia alternativa basada en experimentación directa y modelización econométrica para desarrollar medidas objetivas de la fortaleza de las instituciones estatales, no sólo para un análisis cross-section contemporáneo, sino también (para la segunda) para datos históricos cross-time esenciales para rastrear el desarrollo de las instituciones.
Distinct chitinases are expressed during various growth phases of the human pathogen Paracoccidioides brasiliensis
Santana, Lidiane Aparecida da Penha;Vainstein, Marilene Henning;Tomazett, Patrícia Kott;Santos-Silva, Ludier Kesser;Góes, Alfredo Miranda;Schrank, Augusto;Soares, Célia Maria de Almeida;Pereira, Maristela;
Memórias do Instituto Oswaldo Cruz , 2012, DOI: 10.1590/S0074-02762012000300004
Abstract: the aim of this work was the partial purification and subsequent evaluation of chitinase expression during the various growth phases of paracoccidioides brasiliensis. initially, pbcts1r was expressed as a recombinant protein and displayed enzymatic activity against 4-mu-[n-acetylglucosamine (glcnac)]3 and 4-mu-(glcnac)2. two proteins, 45 kda and 39 kda in size, were partially purified from p. brasiliensis yeast crude extract using cation-exchange chromatography coupled with hplc and were characterised as pbcts1 and pbcts2, respectively. anti-pbcts1r antibody recognised two proteins in the crude extracts of yeast and the transitional stage between mycelial and yeast phases. in crude extracts of mycelium, only the 45 kda protein was detected. however, quantitative real-time polymerase chain reaction led to the detection of small quantities of pbcts2 transcript in the mycelial phase. in the yeast cell wall extract, only the 39 kda protein was detected. moreover, both proteins were secreted by the yeast parasitic phase, suggesting that these proteins participate in the modulation of the fungal environment. phylogenetic analysis of the predicted pbcts1 and pbcts2 proteins indicated that they code for distinct chitinases in p. brasiliensis. during evolution, p. brasiliensis could have acquired the paralogues pbcts1 and pbcts2 for growth and survival in diverse environments in both saprophytic and parasitic phases.
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