Characterization of candida oral flora in HIV-1 infected children in the HAART era

Orientador: Maria Marluce dos Santos VilelaTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias MedicasResumo: O presente estudo caracterizou a flora oral de Candida em 52 crianças infectadas pelo HIV-1 em dois períodos, definidos como período I antes da introdução de inibidores de protease no esquema de terapia antiretroviral para HIV-1 e período II após a introdução de inibidores de protease. Comparou-se as espécies de Candida identificadas nos períodos I e II. Isolados do períodos I foram identificados e as crianças em sua maioria (80%) estavam colonizadas por C. albicans. Redução no percentual de colonização por C. albicans de 80% para 52%, nos períodos I e II respectivamente, sugere mudança na colonização oral por Candida após a introdução da terapêutica com inibidores de protease HIV (IP). Destaca-se particularmente o aumento da incidência de isolados Não¿albicans (p=0.005) no período II. No período I haviam 8 crianças que estavam colonizadas por espécies Não-albicans e no período II haviam 20 crianças colonizadas com isolados Não-albicans. Investigou-se a prevalência de C. dubliniensis na família de uma das crianças que estava colonizada por esta levedura. Do total de 52 crianças 38.4% mostraram manifestação oral associada a colonização por Candida. Observou-se alta sensibilidade dos isolados aos agentes antifúngicos testados, mas 4% dos isolados exibiram resistência ao fluconazol. Documentou-se resistência cruzada entre agentes antifúngicos em isolado de Candida albicans em uma criança infectada pelo HIV-1 não previamente exposta a azoles. Um isolado de C. tropicalis mostrou baixa susceptibilidade ao fluconazol (MIC = 64 µg/ml) (1). O presente estudo revelou mudança significativa na colonização oral por Candida em crianças infectadas pelo HIV-1 sob terapia HAART (Highly Active Antiretroviral Therapy). Houve alta diversidade de espécies de Candida, com emergência de espécies Não-albicans após o uso de Inibidores de proteaseAbstract: This study characterized the Candida oral flora from 52 Brazilian HIV 1-infected children, comparing the Candida species identified in two periods before (PI) and under (PII) the introduction of the HIV Protease Inhibitor therapy. The majority (80%) of the children from the PI group were colonized by C. albicans. Children in the PII (52%) were colonized by C. albicans and 28% of them carried on mixed colonization (C. albicans and Non¿albicans isolates). Therefore when we compared the periods I and II, after the inhibitor protease usage there was an important decrease in the percentile of colonization for C. albicans of 80% to 52%, suggesting an important change of the Candida oral colonization after the HIV protease inhibitors introduction. Particularly with increase of the Non-albicans isolates incidence (p=0.005) in the period II. In PI there were 8 children that were colonized by Non-albicans species and in the PII there were 20 children colonized with Non¿albicans isolates. Rare Candida species were identified, particularly we investigated the C. dubliniensis prevalence in a HIV-infected child¿s family. Of 52 children in this study 20 (38.4%) of them showed oral lesions associated to the Candida colonization. In spite of the high susceptibility of the isolates to the antifungal agents tested in this study, 4.4% (n=2) exhibited resistance to the fluconazole. One of the isolates was C. albicans from a HIV-infected child not prior exposure to azoles, which showed antifungal cross-resistance. One C. tropicalis isolate has shown low susceptibility to fluconazol (MIC = 64 µg/ml). This study was succeeded in showing the inhibitory effect of ritonavir on a single hyphae tip growth of C. albicans. The present investigation revealed a significative change of the Candida oral colonization in Brazilian HIV-infected children under HAART, high diversity of Candida species and Non-albicans species emergence after IP usageDoutoradoPediatriaDoutor em Saude da Criança e do Adolescent

A new species of Xylocopa (Nanoxylocopa) from Brazil (Hymenoptera, Apidae)

Xylocopa bella sp. nov., the second known species of the subgenus Xylocopa (Nanoxylocopa) Hurd & Moure, is newly described from the Espinhaço mountain range, in the state of Minas Gerais, and the Chapada Diamantina, in the state of Bahia, in eastern Brazil. It differs from X. ciliata Burmeister, the type species of X. (Nanoxylocopa), mainly by the possession, by females, of pale hairs intermixed with the black pubescence on the head and metasoma, the more abundant pubescence on mesoscutum and the much denser tergal pilosity, and the possession, by the male, of weakly infumated wing membrane, entirely dark scape, a patch of finely plumose pubescence on the anterior corners of the mesoscutum, narrower face, and shorter distance between the lateral ocellus and the eye. Additionally, X. ciliata, previously known from Argentina, Uruguay, Paraguay and southern Brazil, is newly recorded from the state of Minas Gerais

Valorização de biomassa vegetal através de extração com CO2 supercrítico: do laboratório à exploração

Doutoramento em Engenharia QuímicaA investigação no tema de extração com dióxido carbono supercrítico (SFE) de compostos de valor acrescentado a partir de biomassa vegetal tem sido fortemente impulsionada por duas motivações: a valorização de subprodutos e a biorefinaria. Neste trabalho seis estágios diferentes da investigação neste campo são abordados: a caraterização preliminar de extratos, a otimização experimental, a medição de curvas cinéticas, a modelação das mesmas, estudos de escalabilidade (scale-up), e a análise tecno-económica. Para este efeito, selecionaram-se subprodutos e resíduos agroflorestais promissores, a saber: resíduos de café, folhas e ramos de jacinto de água, cortiça de carvalho turco, sementes de moringa, fruto gac, e casca de eucalipto, com especial ênfase neste último pela sua pertinência no contexto industrial português, nomeadamente para o setor da pasta e papel. O trabalho experimental focou-se em extratos crude e compostos bioativos com potencial para aplicações em cosmética e nutracêutica, tais como os ácidos triterpénicos (ácidos ursólico, oleanólico, betulínico), diterpenos (cafestol, kahweol, 16-O-methylcafestol), esteróis (estigmasterol, etc), friedelina, e licopeno. Casca de eucalipto (Eucalyptus globulus): puro ou modificado com etanol, o SC-CO2 foi capaz de remover ácidos triterpénicos, e a medição e modelação de curvas de extração em condições ótimas (200 bar, 40 ºC e 2.5-5.0 % m/m de etanol) apontaram o rácio entre o caudal e a massa de biomassa como o critério de scale-up apropriado para o processo. Seguindo este critério realizou-se com sucesso um scale-up experimental a três escalas: 0.5, 5.0, and 80 L. Cortiça de carvalho turco (Quercus cerris): extratos crude contendo cerca de 35 % m/m de friedelina foram produzidos com sucesso por SFE e as curvas de extração foram modeladas. A seletividade para a friedelina pode atingir 2.5 através da correta seleção do tamanho de partícula, quantidade de cosolvente (etanol) e tempo de extração. Folhas e ramos de jacinto de água (Eichhornia crassipes): extratos ricos em estigmasterol foram obtidos para tempos de extração curtos (<1 h). As condições ótimas para o rendimento total de extração são 250–300 bar e 5.0 % m/m de etanol, enquanto que para os esteróis são 300 bar e 2.5 % m/m Resíduos de tomate (Solanum lycopersicum): tanto o dióxido de carbono como o etano podem ser usados como solvente supercrítico para produzir um óleo essencial que é rico em licopeno. A viabilidade da SFE foi demonstrada, e apesar de o etano conduzir a maior produtividade, mais investigação é necessária para definir qual dos solventes é preferível na globalidade. Fruta gac (Momordica. cochinchinensis): poderá ser uma promissora e economicamente viável fonte de carotenos, quando extraídos por SFE a 400 bar, 70-90 , durante 0.5-1.0 h. Sementes de moringa (Moringa oleifera): uma análise tecno-económica revelou que um processo integrado bem projetado e combinando SFE com destilação a vácuo permite a produção simultânea de um óleo essencial e de um extratos com uma concentração de esteróis de 89.4 %. Borras de café (Coffea spp.): o óleo produzido por SFE é até 4.1 vezes mais rico em diterpenos do que extratos obtidos com n-hexano, e um processo altamente rentável é esperado a nível comercial. No cômputo geral, esta tese contribui para a sistematização de uma abordagem científica e técnica que promova a valorização industrial de biomassa vegetal através da tecnologia de extração supercrítica.The research on supercritical CO2 extraction (SFE) of added value compounds from vegetal biomass has been strongly driven by by-products valorization and biorefinery motivations. In this work, preliminary characterization of extracts, experimental optimization, measurement of kinetic curves, modeling, scale-up, and techno-economic analysis are covered. For this, several promising agro-forest by-products and residues were selected: spent coffee grounds, water hyacinth stalks and leaves, Turkish oak cork, moringa seed, tomato wastes, gac fruit, and eucalypt bark, with a strong emphasis on the latter due to its pertinence for the Portuguese industrial pulp and paper sector. Experimental work focused on bulk extracts and bioactive compounds with potential cosmetic and nutraceutical applications, such as essential oils, triterpenic acids (ursolic, oleanolic, and betulinic acids), diterpenes (cafestol, kahweol, 16-O-methylcafestol), sterols (e.g., stigmasterol), friedeline, and lycopene. The main results are: Eucalypt (Eucalyptus globulus) bark: whether pure or modified with ethanol, SC-CO2 was able to remove triterpenic acids, and the measurement and modeling of extraction curves under optimum conditions (200 bar, 40 ºC and 2.5-5.0 wt.% of ethanol) pointed the ratio between solvent flow rate and biomass weight as the appropriate scale-up criterion of the process. With this criterion, a successful experimental scale-up was achieved at three scales: 0.5, 5.0, and 80 L. Turkish oak (Quercus cerris) cork: bulk extracts containing ca. 35 wt.% of friedeline were successfully produced by SFE and the extraction curves were modeled. The selectivity to friedeline can reach up to 2.5 through a correct selection of particle size, cosolvent (ethanol) amounts and extraction time. Water hyacinth (Eichhornia crassipes) leaves and stalks: stigmasterol enriched extracts were obtained for shorter times (<1 h). The optimized conditions for total extraction yield were 250–300 bar and 5.0 wt.% ethanol, while for sterols were 300 bar and 2.5 wt.%. Tomato (Solanum lycopersicum) wastes: both carbon dioxide and ethane can be used as supercritical solvents to produce an essential oil that is rich in lycopene. The viability of the SFE was demonstrated, but while ethane led to greater productivity, further research is needed to define which one is preferable on a global basis. Gac (Momordica. cochinchinensis) fruit: it may be a promising and economically viable source of carotenes when produced by SFE at 400 bar, 70-90 , during 0.5-1.0 h. Moringa (Moringa oleifera) seeds: a techno-economic analysis unveiled that a well designed integrated process combining SFE and vacuum distillation allows the simultaneous production of an essential oil and a sterols enriched extract with 89.4 % concentration. Spent coffee (Coffea spp.) grounds: the oil produced by SFE is up to 4.1 times richer in diterpenes than n-hexane extracts, and a highly profitable process may be expected at commercial level. In the whole, the presented thesis contributes to the systematization of a scientific and technical approach to foster the industrial valorization of vegetal biomass through SFE technology

Service life of shotcrete : investigation on the effect of set accelerating admixture

Le béton projeté par voie humide est une méthode de mise en place très populaire dans la construction de tunnels et le soutènement de parois dans les mines. L'utilisation d’un adjuvant accélérateur de prise offre des avantages significatifs en gain de productivité et pour la sécurité des travailleurs pendant la réalisation du travail. Cependant, l’effet de ces adjuvants, et particulièrement leur dosage, sur la durée de vie du béton projeté est mal compris et souvent négligé. Le dosage de l’adjuvant en chantier est souvent élevé, ce qui a pour conséquence de faire augmenter les coûts de production et réduire la qualité du béton. Cette recherche a pour objectif d’étudier l'influence de l'utilisation des accélérateurs de prise sur la durabilité du béton comme matériau, en considérant les particularités du béton projeté et en profitant des avancées faites en matière de prédiction de la durée de vie des bétons conventionnels. L’effet d’un adjuvant accélérateur de prise (à différents dosages) à base de sulfate d’aluminium (A/$) sera étudié. Les résultats permettront d’améliorer la qualité des applications de béton projeté dans l'industrie de la construction et les devis qui, chaque jour, sont plus exigeants et requièrent des performances de plus en plus élevées. Les données générées à partir des différents essais réalisés sont très intéressantes, car elles démontrent la complexité d’une telle étude à cause des changements non proportionnels des caractéristiques du béton avec différents dosages d’accélérateur de prise. De plus, les données générées illustrent bien l'influence de l’adjuvant accélérateur de prise sur la qualité du béton.Wet-mix shotcrete is a widely used placement method in tunnelling and ground support. The use of a set accelerating admixture provides significant advantages in terms of productivity gains and worker safety during work progress. However, knowledge about adverse effects linked the use of set accelerator admixture (and particularly its dosage) is very limited. Indeed, dosage control is sometimes overlooked on the job site or the accelerator may be misguidedly overdosed, with the consequence of increasing costs and reducing the quality of the in-place shotcrete. The goal of this research is to study and better understand the effects of the use of set accelarating admixture on the durability of concrete as a material, starting with the particularities of shotcrete and taking advantage of the latest tools in modelling service life of conventional concretes. An alkali-free set accelerating admixture (at different dosages) based on aluminium-sulphate salts (A/$) will be investigated. The results will help improve the quality of shotcrete applications in the construction industry, and specifications which are increasingly demanding and require everimproving performances. The data generated from the several tests performed is very interesting, because it shows the intricacies of such an investigation due to the non-linear changes of concrete using different set accelerator dosages. It also demonstrates clearly the effects of using high dosages of set accelerating admixtures on the quality of shotcrete

Estudo de hidrolases glicosídicas bacterianas para aplicações biotecnológicas : bioprospecção, produção e imobilização

Orientadores: Hélia Harumi Sato, Roberto RullerTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de AlimentosResumo: A biomassa lignocelulósica é um importante recurso renovável que está prontamente disponível, sendo uma fonte de matéria-prima com alto potencial biotecnológico. Os polissacarídeos complexos que compõem lignocelulose podem ser convertidos em monossacarídeos fermentescíveis, com grande aplicabilidade em diversos bioprocessos industriais. A degradação dos materiais lignocelulósicos pode ser realizada por uma diversidade de vias enzimáticas complexas, onde é requerido um número considerável de enzimas ativas sobre carboidratos. Entre elas, as famílias das celulases e hemicelulases, além de atuarem na hidrólise dos materiais lignocelulósicos, possuem um uso versátil em setores industriais, tais como, nas áreas alimentícia, bebidas e de biocombustíveis. A tese teve como principais objetivos o delineamento de estratégias para a produção de enzimas e coquetéis enzimáticos eficientes para o uso na hidrólise da biomassa vegetal e, a aplicação de técnicas de imobilização para ampliar a utilização de enzimas em escala comercial. Inicialmente, a bioprospecção de novos micro-organismos secretores de enzimas atuantes na biomassa lignocelulósica foi realizada, e dentre as oitenta linhagens de Streptomyces testadas, duas linhagens (F1 e F7) se destacaram por apresentarem elevadas atividades celulolíticas e hemicelulolíticas. Uma abordagem genômica dessas linhagens possibilitou a identificação de 85 hidrolases glicosídicas (GHs) distribuídas em 33 famílias diferentes na linhagem F1, e 100 GHs dispostas em 44 famílias na linhagem F7. Além disso, os dados genômicos das linhagens F1 e F7 também indicaram a presença de genes relacionados à degradação da lignina. Ferramentas estatísticas também foram aplicadas e possibilitaram a ampliação da produção de GHs pela linhagem F1. Com a otimização, elevadas concentrações de GHs foram alcançadas com meio nutriente adicionado de 16,4 g L-1 de farelo de trigo e 10,0 g L-1 de caseína, onde se obteve 9,27 U mL -1 de xilanase e 0,22 U mL -1 de celulase. Para confirmar a diversidade de GHs expressas pela linhagem F1, uma análise por espectrometria de massa foi realizada e observou-se que quanto maior a complexidade da fonte de carbono utilizada, maior foi a gama de proteínas expressas, incluindo vários tipos de celulases e hemicelulases. A eficiência do extrato enzimático produzido pela linhagem F1 foi estudada para a sacarificação da biomassa vegetal e possibilitou um aumento significativo na liberação de açúcares quando adicionado ao extrato celulolítico comercial, indicando que as enzimas secretadas pela Streptomyces sp. F1 podem ser aplicadas para o melhoramento dos atuais coquetéis comerciais. Foi estudada também a criação de métodos de imobilização de enzimas em condições neutras de pH. Os novos suportes produzidos com a agarose foram utilizados para a imobilização de enzimas monoméricas e multiméricas de grande importância biotecnológica. Um estudo mais detalhado explorando os novos suportes e o uso de técnicas de pós-imobilização foi também proposto. O processo desenvolvido aplicando o polímero polietilenimina (PEI) possibilitou a formação de um excelente sistema para imobilizar e estabilizar a ?-glicosidase obtida de Exiguobacterium antarcticum. A ?-glicosidase imobilizada apresentou uma melhora em suas características, incluindo estabilidade térmica e de armazenamento. Além disso, a ?-glicosidase manteve sua atividade elevada mesmo após vários ciclos de hidrólise com celobiose como substratoAbstract: Lignocellulosic biomass is an important renewable resource that is readily available, being a source of raw material with high biotechnological potential. The complex polysaccharides that compose lignocellulose can be converted into fermentable monosaccharides, with great applicability in several industrial bioprocesses. The degradation of lignocellulosic materials can be accomplished by a variety of complex enzymatic pathways, where a considerable number of carbohydrate active enzymes are required. Among them, the families of cellulases and hemicellulases, besides acting in the hydrolysis of lignocellulosic materials, have a versatile use in industrial sectors, such as in food, beverages and biofuels. The main aims of this thesis were the design of efficient strategies for the production of enzymes and enzymatic cocktails for use in plant biomass hydrolysis and the application of immobilization techniques to increase the use of enzymes in a commercial scale. Initially, bioprospection of new enzyme secreting microorganisms active in lignocellulosic biomass was performed, and among the eighty Streptomyces strains tested, two strains (F1 and F7) were distinguished by their high cellulolytic and hemicellulolytic activities. A genomic approach of these strains allowed the identification of 85 glycoside hydrolases (GHs) distributed in 33 different families the strain F1, and 100 GHs arranged in 44 families the strain F7. In addition, the genomic data from strains F1 and F7 also indicated the presence of genes related to lignin degradation. Statistical tools were also applied and allowed the increase in GH production by strain F1. With the optimization, high concentrations of GHs were achieved with a nutrient medium containing 16.4 g L-1 of wheat bran and 10.0 g L-1 of casein, where 9.27 U mL-1 of xylanase and 0.22 U mL-1 of cellulase were obtained. To confirm the diversity of GHs expressed by the strain F1, an analysis using mass spectrometry technique was performed and it was observed that the greater the complexity of the carbon source used, the greater the range of proteins secreted, including several types of cellulases and hemicellulases. The efficiency of the enzymatic extract produced with strain F1 was studied for the saccharification of plant biomass and allowed a significant increase in sugar release when added to the commercial cellulolytic extract, indicating that the enzymes expressed by Streptomyces sp. F1 can be applied for the improvement of the current commercial cocktails. The creation of enzyme immobilization methods under neutral conditions of pH was also study. The new agarose supports were used for the immobilization of monomeric and multimeric enzymes of great industrial and biotechnological importance. A more detailed study exploring the new supports and the use of post-immobilization techniques with polymers and small molecules was also proposed. The process developed by applying the polymer polyethyleneimine (PEI) enabled the formation of an excellent system to stabilize the glucose-tolerant tetrameric ?-glycosidase obtained from Exiguobacterium antarcticum. The immobilized ?-glycosidase showed an improvement in its characteristics, with an increased activity, including thermal and storage stability. In addition, the ?-glycosidase maintained a high activity even after several cycles of hydrolysis applying cellobiose as substrateDoutoradoCiência de AlimentosDoutor em Ciência de Alimentos140610/2014-6CNP

Genome-wide Determination Of Splicing Efficiency And Dynamics From RNA-Seq Data

Eukaryotic genes are mostly composed of a series of exons intercalated by sequences with no coding potential called introns. These sequences are generally removed from primary transcripts to form mature RNA molecules in a post-transcriptional process called splicing. An efficient splicing of primary transcripts is an essential step in gene expression and its misregulation is related to numerous human diseases. Thus, to better understand the dynamics of this process and the perturbations that might be caused by aberrant transcript processing, it is important to quantify splicing efficiency. In this thesis, I introduce SPLICE-q, a fast and user-friendly Python tool for genome-wide SPLICing Efficiency quantification. It supports studies focusing on the implications of splicing efficiency in transcript processing dynamics. SPLICE-q uses aligned reads from RNA-Seq to quantify splicing efficiency for each intron individually and allows the user to select different levels of restrictiveness concerning the introns’ overlap with other genomic elements, such as exons from other genes. I demonstrate SPLICE-q’s application using three use cases including two different species and methodologies. These analyses illustrate that SPLICE-q can detect a progressive increase of splicing efficiency throughout a time course of nascent RNA-Seq and it might be useful when it comes to understanding cancer progression beyond mere gene expression levels. Furthermore, I provide an in-depth study of time course nascent BrU-Seq data to address questions concerning differences in the speed of splicing and the underlying biological features that might be associated with it. SPLICE-q and its documentation are publicly available at: https://github.com/vrmelo/SPLICE-q.Eukaryotische Gene bestehen im Wesentlichen aus einer Reihe von Exons, die durch nicht-kodierende Sequenzen (so genannte Introns) getrennt sind. In einem posttranskriptionellen Prozess, der als Splicing bzw. Spleißen bezeichnet wird, werden diese Sequenzen üblicherweise aus den primären Transkripten entfernt, sodass reife RNA Moleküle entstehen. Effizientes Splicing der primären Transkripte ist ein derart essenzieller Schritt in der Expression von Genen, dass dessen Deregulation Ursache zahlreicher Erkrankungen des menschlichen Körpers ist. Deswegen ist es wichtig die Effizienz des Spleißens robust quantifizieren zu können, um die Dynamik dieses Prozesses und die Auswirkungen der aberranten Prozessierung von Transkripten besser zu verstehen. In diesem Manuskript präsentiere ich SPLICE-q, ein effizientes und benutzerfreundliches Pythonprogramm zur genomweiten Quantifizierung von Spleißeffizienzen (SPLICing Efficiency quantification). Es unterstützt u.a. Studien, die den Effekt von Spleißeffizienz auf die generelle Dynamik der Transkriptprozessierung untersuchen. SPLICE-q benutzt alignierte Reads aus RNA-Seq Experimenten, um die Spleißeffizienz für jedes einzelne Intron zu quantifizieren und erlaubt es dem Benutzer Introns in mehreren unterschiedlich restriktiven Stufen nach deren Überlapp mit anderen genomischen Elementen (bspw. Exons aus anderen Genen) zu filtern. Die Verwendung und Robustheit von SPLICE-q wird anhand von drei verschiedenen Anwendungsbeispielen, inkl. zweier unterschiedlicher Spezies und Methodologien, gezeigt. Diese Analysen demonstrieren, dass SPLICE-q in der Lage ist sowohl, anhand von Daten eines nascent RNA Experiments, einen progressiven Anstieg der Spleißeffizienz über die Zeit festzustellen, als auch zum Verständnis der Entwicklung von Krebszellen, über die bloße Genexpression hinaus, beizutragen. Darüber hinaus, untersucht diese Arbeit eine Zeitreihe aus nascent BrU-Seq-Daten im Detail, um Fragestellungen bzgl. Differenzen in der Spleißgeschwindigkeit in Verbindung mit gewissen biologischen Merkmalen zu klären. Der Quellcode von SPLICE-q und dessen Dokumentation sind öffentlich zugänglich unter: https://github.com/vrmelo/SPLICE-q

Finding the Self through Travel: A Psychoanalytic Analysis of Self-Discovery and Transformation in Travel Writing

My thesis addresses the themes of self-discovery and transformation in travel literature. The travel writing narrative reinforces a cultural and personal consciousness in which mobility, observation, curiosity, accuracy, and imagination become qualities fundamental to understanding oneself. Journeys of self-discovery are a popular form of narrative in travel literature. Using Paulo Coelho’s The Alchemist, William Least Heat-Moon’s Blue Highways: A Journey into America, and Elizabeth Gilbert’s Eat, Pray, Love, I argue that the combination of the characters being in a foreign environment and searching for their identities reflects the reader’s dreams and desire for exploration and self-discovery. The characters in these novels go on a journey where they not only discover new parts of the world but also something new about themselves. I will address these themes using the reader theory from psychoanalytic criticism as well as look at how writing and reading materialize unconscious thoughts. Understanding these theories allows for a study of the reader’s response, reaction, and interpretation of the text. In the end, change and transformation in travel literature are both physical and mental, affecting not only the places visited but also the characters and the reader’s mind. This transformation can sometimes be difficult to accept but travel narratives encourage us not to resist change but to adapt to it

Electrochemical biosensors in pharmaceutical analysis

Given the increasing demand for practical and low-cost analytical techniques, biosensors have attracted attention for use in the quality analysis of drugs, medicines, and other analytes of interest in the pharmaceutical area. Biosensors allow quantification not only of the active component in pharmaceutical formulations, but also the analysis of degradation products and metabolites in biological fluids. Thus, this article presents a brief review of biosensor use in pharmaceutical analysis, focusing on enzymatic electrochemical sensors.Em virtude do aumento da demanda por técnicas analíticas simples e de baixo custo, os biossensores têm atraído a atenção para a análise de fármacos, medicamentos e outros analitos de interesse em controle de qualidade de medicamentos. Os biossensores permitem a quantificação não somente de princípio ativo em formulações farmacêuticas, mas também de produtos de degradação e metabólitos em fluídos biológicos, bem como análise de amostras de interesse clínico e industrial, além de possibilitar a determinação de enantiômeros. Desta forma, este artigo objetiva fazer uma breve revisão a respeito do emprego de biossensores em análise farmacêutica, com ênfase em sensores eletroquímicos enzimáticos