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Redes de interação entre plantas e frugivoros na mata atlantica : estrutura e fragilidade a extinções; Interactions network between plants and frugivores in the Atlantic Forest : structure and fragility

Maria Clara Oleski Amatuzzi
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/02/2009 PT
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O mutualismo planta-frugívoro é bem conhecido como importante processo na manutenção dos ecossistemas. O frugívoro obtém o recurso alimentar da polpa e dispersa as sementes da planta. A crescente perda e fragmentação de ambientes naturais devem afetar essas interações. Portanto, conhecer quais são os efeitos desta degradação na dispersão de sementes é um passo importante na tentativa de preservação dos ecossistemas. A abordagem de redes vem sendo usada atualmente a fim de entender melhor a estrutura, funcionamento e evolução de diversos tipos de interações. Explorei alguns padrões de extinção de espécies em uma rede de interações mutualísticas frugívoro-planta do Parque Estadual de Intervales (PEI) simulando extinções de frugívoros e plantas e observando os efeitos na sua estrutura. A rede frugívoro-planta do PEI é uma rede típica de interações mutualísticas com estrutura extremamente aninhada; baixa conectância; baixos graus médios tanto de plantas como dos animais; prevalência de interações fracas e ocorrência de interações assimétricas. As co-extinções ocorreram muito lentamente com as remoções de especialistas e geram um declínio considerável na riqueza de espécies do outro grupo...

Interações físicas e químicas entre isolado protéico de soja e glúten vital durante a extrusão termoplástica a alta e baixa umidade para a obtenção de análogo de carne = : Physical and chemical interactions between isolated soy protein and vital gluten during thermoplastic extrusion at high and low moisture content to obtain meat analogue; Physical and chemical interactions between isolated soy protein and vital gluten during thermoplastic extrusion at high and low moisture content to obtain meat analogue

Marcio Schmiele
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 26/02/2014 PT
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Os análogos de carne obtidos por extrusão termoplástica de proteínas vegetais são caracterizados pelo seu elevado teor proteico e estrutura semelhante às fibras da carne, envolvendo diversos tipos de ligações e/ou interações químicas entre as proteínas. O objetivo deste trabalho foi avaliar as características tecnológicas e físico-químicas de análogos de carne, à base de isolado proteico de soja, obtidos por processo de extrusão termoplástica a alta umidade (AU) e baixa umidade (BU). Para cada condição de umidade foi utilizado um Delineamento Composto Central Rotacional de três variáveis independentes (glúten vital, umidade de condicionamento e temperatura de extrusão). As variáveis dependentes avaliadas foram a textura instrumental, cor instrumental, capacidade de absorção de água, índice de solubilidade em água, capacidade de absorção de óleo, índice de dispersibilidade de proteína, energia mecânica específica e o tipo de interações proteicas. Estas interações foram avaliadas através de sete tipos de solventes específicos: (i) tampão fosfato para as proteínas no estado nativo; (ii) dodecil sulfato de sódio para as interações hidrofóbicas e iônicas; (iii) Triton 100X para as interações hidrofóbicas; (iv) ureia para as interações hidrofóbicas e pontes de hidrogênio; (v) ß-mercaptoetanol para as ligações dissulfeto; e (vi) ß-mercaptoetanol e ureia e (vii) dodecil sulfato de sódio e ureia...

Lateral interactions in visual perception of temporal signals: cortical and subcortical components

Teixeira,Claudio E. C.; Silveira,Luiz Carlos L.; Kremers,Jan
Fonte: Pontificia Universidade Católica do Rio de Janeiro; Universidade de Brasília; Universidade de São Paulo Publicador: Pontificia Universidade Católica do Rio de Janeiro; Universidade de Brasília; Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2011 EN
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The aim of this work was to isolate and investigate subcortical and cortical lateral interactions involved in flicker perception. We quantified the perceived flicker strength (PFS) in the center of a test stimulus which was simultaneously modulated with a surround stimulus (50% Michelson contrast in both stimuli). Subjects were requested to adjust the modulation depth of a separate matching stimulus that was physically identical to the center of the test stimulus but without the surround. Using LCD goggles, synchronized to the frame rate of a CRT screen, the center and surround could be presented monoptically or dichoptically. In the monoptic condition, center-surround interactions can have both subcortical and cortical origins. In the dichoptic condition, center-surround interactions cannot occur in the retina and the LGN, therefore isolating a cortical mechanism. Results revealed both a strong monoptic (subcortical plus cortical) lateral interaction and a weaker dichoptic (cortical) lateral interaction. Subtraction of the dichoptic from the monoptic data revealed a subcortical mechanism of the lateral interaction. While the modulation of the cortical PFS component showed a low-pass temporal-frequency tuning, the modulation of the subcortical PFS component was maximal at 6 Hz. These findings are consistent with two separate temporal channels influencing the monoptic PFS...

Mutations in the N-Terminal Domains of Nectin-1 and Nectin-2 Reveal Differences in Requirements for Entry of Various Alphaherpesviruses and for Nectin-Nectin Interactions

Struyf, Frank; Martinez, Wanda M.; Spear, Patricia G.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /12/2002 EN
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Nectin-1 and nectin-2 are related molecules that can function with different specificities as entry receptors for mammalian alphaherpesviruses through interaction with viral glycoprotein D (gD). The normal function of members of the nectin family is to mediate cell-cell adhesion through homotypic and heterotypic nectin-nectin interactions in cadherin-based adherens junctions. We examined mutations in three equivalent regions of the N-terminal V-like domains of nectin-1 and nectin-2 to test the effects on entry of various alphaherpesviruses, nectin-nectin interactions, and interactions of the mutant nectins with gD. Mutations in region I previously shown to severely impair herpes simplex virus (HSV) entry activity, but not pseudorabies virus (PRV) or bovine herpesvirus 1 (BHV-1) entry, did not reduce homotypic trans interactions for either nectin-1 or nectin-2 or binding of nectin-3 to nectin-1. Mutations in region II, patterned after a reported single-nucleotide polymorphism in nectin-2, enhanced intracellular accumulation of both nectin-1 and nectin-2 and had a deleterious effect on all of the activities under study. Mutations in region III previously shown to reduce homotypic trans interactions of nectin-2 impaired the entry of PRV and BHV-1 when introduced into either nectin-1 or nectin-2...

Ecologia das interações entre formigas e plantas com nectários extraflorais em uma savana neotropical: variação temporal na rede de interações e seus efeitos sobre a herbivoria foliar; Ecology of interactions between ants and plants with extrafloral nectaries in a neotropical savanna: temporal variation in the network of interactions and their effects on leaf herbivory

Lange, Denise
Fonte: Universidade Federal de Uberlândia Publicador: Universidade Federal de Uberlândia
Tipo: Tese de Doutorado
POR
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Estudos de interações envolvendo formigas e plantas com nectários extraflorais são comuns na literatura, entretanto, devido à grande diversidade de espécies envolvidas e à variação nos resultados das interações, pouco se conhece a respeito da dinâmica e estrutura dessas relações no âmbito da comunidade. Dessa forma, este estudo propôs avaliar a estrutura da rede formada pela associação entre formigas e plantas com nectários extraflorais e o resultado dessa interação para o módulo mais representativo da comunidade de plantas do cerrado em um período de dois anos (setembro de 2008 a agosto de 2010). As espécies de plantas estudadas foram Caryocar brasiliense, Lafoensia pacari, Ouratea hexasperma, O. spectabilis, Qualea grandiflora, Q. multiflora, Q. parviflora, Stryphnodendron adstringens e S. polyphyllum. No total, 34 espécies de formigas estiveram associadas às nove espécies plantas. A rede de interação formada por esses dois grupos de organismos apresentou características semelhantes às outras redes mutualísticas, como: aninhamento, assimetria na especialização e baixa especialidade. Esse padrão se manteve durante os dois anos do estudo apesar de ter havido alterações na quantidade de associações e nas espécies de formigas presentes na rede. O pico de associações entre plantas e formigas correspondeu ao início da estação chuvosa...

L’expérience de proches aidants au regard de leurs interactions sociales avec un parent atteint de démence et présentant un comportement d’errance en centre d’hébergement

Dion, Rosalie
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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Le but de cette étude était d’explorer et de comprendre l’expérience que peuvent vivre les proches aidants au regard de leurs interactions avec leur parent âgé qui erre, lors de leurs visites au centre d’hébergement et de soins de longue durée. Une étude qualitative exploratoire a été réalisée en s’inspirant de la conception des interactions sociales de Khosravi (2003, 2007) et de la théorie de l’être humain unitaire de Rogers (1970, 1990). À l’aide d’un guide d’entretien semi-dirigé, des entrevues individuelles ont été effectuées auprès de cinq filles aidantes ayant un parent errant hébergé. Le but de cette étude était d’explorer et de comprendre l’expérience que peuvent vivre les proches aidants au regard de leurs interactions avec leur parent âgé qui erre, lors de leurs visites au centre d’hébergement et de soins de longue durée. Une étude qualitative exploratoire a été réalisée en s’inspirant de la conception des interactions sociales de Khosravi (2003, 2007) et de la théorie de l’être humain unitaire de Rogers (1970, 1990). À l’aide d’un guide d’entretien semi-dirigé, des entrevues individuelles ont été effectuées auprès de cinq filles aidantes ayant un parent errant hébergé. Les résultats de l’analyse thématique suggèrent que ces aidantes sont en mesure d’expliquer l’errance en identifiant plusieurs causes à ce comportement...

Searching for novel gene functions in yeast : identification of thousands of novel molecular interactions by protein-fragment complementation assay followed by automated gene function prediction and high-throughput lipidomics

Tarasov, Kirill
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
EN
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La compréhension de processus biologiques complexes requiert des approches expérimentales et informatiques sophistiquées. Les récents progrès dans le domaine des stratégies génomiques fonctionnelles mettent dorénavant à notre disposition de puissants outils de collecte de données sur l’interconnectivité des gènes, des protéines et des petites molécules, dans le but d’étudier les principes organisationnels de leurs réseaux cellulaires. L’intégration de ces connaissances au sein d’un cadre de référence en biologie systémique permettrait la prédiction de nouvelles fonctions de gènes qui demeurent non caractérisées à ce jour. Afin de réaliser de telles prédictions à l’échelle génomique chez la levure Saccharomyces cerevisiae, nous avons développé une stratégie innovatrice qui combine le criblage interactomique à haut débit des interactions protéines-protéines, la prédiction de la fonction des gènes in silico ainsi que la validation de ces prédictions avec la lipidomique à haut débit. D’abord, nous avons exécuté un dépistage à grande échelle des interactions protéines-protéines à l’aide de la complémentation de fragments protéiques. Cette méthode a permis de déceler des interactions in vivo entre les protéines exprimées par leurs promoteurs naturels. De plus...

Operational interactions between marine mammals and commercial fisheries in Australian and South Pacific waters: characterisation and options for mitigation.

Hamer, Derek J.
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2013
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Reports of interactions between marine mammals and fisheries are on the increase globally. This is mainly because fishery effort has increased to feed the burgeoning human population and because advances in technology have allowed fisheries to exploit habitats that were until recently inaccessible. Additionally, many marine mammal populations decimated by harvesting over the past few hundred years are recovering and the growing conservation community is paying unprecedented attention to their welfare and conservation generally, with growing interest in their interactions with fisheries. Operational interactions are conspicuous and involve the close contact of marine mammals with fishing gear, either because marine mammals opportunistically or habitually target fishing activities to depredate (i.e. attempt to consume) caught fish, or because marine mammals incidentally encounter fishing gear while foraging naturally. Operational interactions often result in negative outcomes for the conservation and welfare of the marine mammals involved and for the economic viability of the fisheries involved. Marine mammals that become by-caught may receive life threatening injuries from entanglements, or may drown, thus having adverse impacts on small or recovering populations. Fisheries that are targeted by depredating marine mammals may need to replace damaged fishing gear...

Investigating the role of biotic interactions in determining the degree of local adaptation and thus the potential response of plants to climate change; Untersuchung der Rolle biotischer Interaktionen für den Grad der lokalen Anpassung bei Pflanzen und der daraus folgenden potentiellen Reaktion von Pflanzen auf den Klimawandel

Tomiolo, Sara
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
EN
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Efficiently predicting the response of plant species to climate is one priority issue of present research, especially for Eastern Mediterranean systems, which according to predictions will be subject to increasing aridity. Current predictions on future species response to the expected change though are based on abiotic factors and virtually neglect the role of biotic interactions. The present thesis investigated the combined effect of climate, soil abiotic properties and biotic interactions on plant populations and community performance and potentially on their response to climate change. Firstly, the performance of plant species was investigated in the field performing a reciprocal seed sowing and soil transplant experiment combined with neighbour treatments between two sites along an aridity gradient. Four species were chosen in order to investigate species-specific effects. Secondly, a similar experiment was performed under controlled conditions with an additional soil treatment to tease apart the effects of soil abiotic properties and soil biota on plants. Thirdly, the change in species composition and richness of the communities emerging from transplanted soils under different climatic conditions were investigated in order to predict potential directions of community shifts under changed climate. The study was based on an integrated approach in which two types of biotic interactions that have been so far addressed separately were combined and analyzed jointly. By focusing on different spatial scales we were able to single out the driving factors and the main forces at play at the level of species and communities. Furthermore...

Application of information extraction techniques to pharmacological domain : extracting drug-drug interactions

Segura Bedmar, Isabel
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/doctoralThesis Formato: application/pdf
ENG
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Una interacción farmacológica ocurre cuando los efectos de un fármaco se modifican por la presencia de otro. Las consecuencias pueden ser perjudiciales si la interacción causa un aumento de la toxicidad del fármaco o la disminución de su efecto, pudiendo provocar incluso la muerte del paciente en los peores casos. Las interacciones farmacológicas no sólo suponen un grave problema para la seguridad del paciente, sino que además también conllevan un importante incremento en el gasto médico. En la actualidad, el personal sanitario tiene a su disposición diversas bases de datos sobre interacciones que permiten evitar posibles interacciones a la hora de prescribir un determinado tratamiento, sin embargo, estas bases de datos no están completas. Por este motivo, médicos y farmacéuticos se ven obligados a revisar una gran cantidad de artículos científicos e informes sobre seguridad de medicamentos para estar al día de todo lo publicado en relación al tema. Desgraciadamente, el gran volumen de información al respecto hace que estos profesionales estén desbordados ante tal avalancha. El desarrollo de métodos automáticos que permitan recopilar, mantener e interpretar toda esta información es crucial a la hora de conseguir una mejora real en la detección temprana de las interacciones entre fármacos. Por tanto...

Découverte de nouvelles interactions entre le virus de l'Hépatite C et l'hôte par une approche combinée de Spectrométrie de Masse et de Génomique Fonctionnelle

Germain, Marie-Anne
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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La réplication et l’assemblage du virus de l’hépatite C (VHC) sont régulés finement dans le temps et l’espace par les interactions protéiques entre le virus avec l’hôte. La compréhension de la biologie du virus ainsi que sa pathogénicité passe par les connaissances relatives aux interactions virus/hôte. Afin d’identifier ces interactions, nous avons exploité une approche d’immunoprécipitation (IP) couplée à une détection par spectrométrie de masse (MS), pour ensuite évaluer le rôle des protéines identifiées dans le cycle viral par une technique de silençage génique. Les protéines virales Core, NS2, NS3/4A, NS4B, NS5A et NS5B ont été exprimées individuellement dans les cellules humaines 293T et immunoprécipitées afin d’isoler des complexes protéiques qui ont été soumis à l’analyse MS. Ainsi, 98 protéines de l’hôte ont été identifiées avec un enrichissement significatif et illustrant une spécificité d’interaction. L’enrichissement de protéines connues dans la littérature a démontré la force de l’approche, ainsi que la validation de 6 nouvelles interactions virus/hôte. Enfin, le rôle de ces interactants sur la réplication virale a été évalué dans un criblage génomique par ARN interférant (ARNi). Deux systèmes rapporteurs de la réplication virale ont été utilisés : le système de réplicon sous-génomique (Huh7-Con1-Fluc) et le système infectieux (J6/JFH-1/p7Rluc2a)...

Interactions didactiques en classe de français : enseignement/apprentissage de l’accord du verbe en première secondaire

Gauvin, Isabelle
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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Notre recherche vise à décrire les connaissances grammaticales élaborées par des élèves de première secondaire au cours de l’enseignement/apprentissage de l’accord du verbe. Cette description se fonde sur l’observation des interactions didactiques entre les élèves, et leur enseignant autour de l’objet de savoir « accord du verbe » : elle concerne plus particulièrement l’interaction entre les pôles « élève » et « savoir ». Notre recherche s’inscrit dans le courant de la grammaire pédagogique moderne. La théorie de la transposition didactique de Chevallard (1985/1991) constitue également la pierre angulaire de nos travaux : les concepts de transposition didactique externe (le passage du savoir savant au savoir à enseigner) et interne (le passage du savoir à enseigner au savoir effectivement enseigné) agissent à titre d’analyseurs des interactions didactiques. L’observation, la description et la théorisation des interactions didactiques imposent une démarche écologique pour la collecte des données. Pour notre recherche, les données ont été recueillies grâce à la captation vidéo de séquences didactiques portant sur l’accord du verbe : elles consistent en des interactions verbales entre élèves ou entre les élèves et leur enseignant. L’analyse des données s’est effectuée selon une perspective macro et micro : (1) L’analyse macro indique que les connaissances antérieures des élèves résistent à l’institutionnalisation des savoirs puisque le savoir enseigné n’est pas celui qui est exclusivement mobilisé. Les élèves recourent à un vaste éventail de connaissances de types procédural et déclaratif pour l’identification du verbe et du sujet...

Effet de la température sur les interactions trophiques et intraguildes au sein d’un système plante-herbivore-ennemis naturels : modélisation et approches expérimentales

Sentis, Arnaud
Fonte: Université de Montréal Publicador: Université de Montréal
Tipo: Thèse ou Mémoire numérique / Electronic Thesis or Dissertation
FR
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Il est maintenant reconnu que les changements climatiques ont des impacts importants sur l’ensemble des organismes vivants. Parmi les facteurs de ces changements, la température occupe une place prépondérante pour les organismes ectothermes car elle régule leur métabolisme. Toutefois, bien que les effets de la température sur les individus d’une espèce soient largement connus, les connaissances demeurent limitées quant aux conséquences sur les interactions trophiques. Dans ce contexte, notre étude s’intéresse aux effets de la température sur un système biologique composé d’une plante, le poivron Capsicum annuum L., d’un herbivore, le puceron Myzus persicae Sulzer (proie extraguilde), ainsi que de deux de ses ennemis naturels : la coccinelle maculée Coleomegilla maculata lengi Timberlake (prédateur intraguilde) et la cécidomyie prédatrice Aphidoletes aphidimyza Rondani (proie intraguilde). Dans ce but, nous avons opté pour une approche multiple comprenant : (1) la modélisation des interactions prédateur-proie et intraguilde (prédation entre deux compétiteurs d’espèces différentes qui exploitent une même ressource), (2) la réalisation d’expériences empiriques en laboratoire permettant de tester les prédictions des modèles et de caractériser l’effet de la température et de ses variations sur les composantes du système biologique étudié. Conformément aux prédictions d’un premier modèle...

Análise conformacional e estudo das interações eletrônicas de algumas (α-fenilseleno-α-etiltio)-,(α-fenilseleno-α-etilsulfinil)- e (α-fenilseleno-α-etilsulfonil)-acetofenonas-para-substituídas; Conformational analysis and electronic interactions study of some (α-phenylseleno-α-ethylthio)-, (α-phenylseleno-α-ethylsulfinyl)- and (α-phenylseleno-α-ethylsulfonyl)-acetophenones-para-substituted

Cerqueira Junior, Carlos Rogério
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 29/01/2013 PT
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A presente tese trata da análise conformacional e estudo das interações eletrônicas de algumas 2-(fenilseleno)-2-(etiltio)acetofenonas (série I), 2-(fenilseleno)-2-(etilsulfinil)- acetofenonas [série IIa para (CRSR/CSSS) e série IIb para (CRSS//CSSR)] e 2-(fenilseleno)-2- (etilsulfonil)acetofenonas (série III) contendo substituintes doadores e atraentes de elétrons, além de hidrogênio na posição para do grupo fenacila. Foi constatada a ocorrência de isomerismo conformacional por espectroscopia no infravermelho em solventes de constante dielétrica crescente (n-C6H14, CCl4, CHCl3, CH2Cl2, CH3CN) em todas as séries estudadas. Os resultados obtidos por infravermelho são concordantes com as estruturas obtidas por otimização estrutural no nível de teoria B3LYP/6-31+G(d,p) com o efeito do solvente simulado pelo método PCM. As interações eletrônicas foram investigadas a partir dos contatos interatômicos e por meio da análise das interações orbitalares (NBO). Foram obtidas as estruturas cristalográficas de alguns compostos selecionados das séries IIa, IIb e III por difração de raio-X. Na série I, o confôrmero mais estável é caracterizado pelas interações orbitalares entre carbonila e enxofre, com o grupo etiltio numa geometria sinclinal em relação à carbonila...

A pharmacoepidemiologic study of drug interactions in a Brazilian teaching hospital

Cruciol-Souza,Joice Mara; Thomson,João Carlos
Fonte: Faculdade de Medicina / USP Publicador: Faculdade de Medicina / USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2006 EN
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PURPOSE: Although drug-drug interactions constitute only a small proportion of adverse drug reactions, they are often predictable and therefore avoidable or manageable. There are few studies on drug-drug interactions from Brazil. This study aimed to assess the frequency of drug-drug interactions in prescriptions and their potential clinical significance in patients of a Brazilian teaching hospital. METHODS: From January to April 2004, a sample of 1785 drug prescriptions was drawn from a total of 11,250. Drug-drug interactions were identified by using Micromedex® DrugReax® System. Patients'records with major drug-drug interactions were reviewed by a pharmacist and a medical doctor looking for signs, symptoms, and lab tests that could indicate adverse drug reactions due to such interactions. RESULTS: From the 1785 prescriptions examined, 1089 (61%) were from the male adult ward. Patients' average age was 52.7 years (SD = 18.9; range, 12-98). The median number of drugs in each prescription was 7 (range, 2-26). At least 1 drug-drug interactions was present in 887 (49.7%) prescriptions. Regarding the severity of the clinical result, the interactions were classified as minor (20; 2.3%), moderate (184; 20.7%), major (30; 3.4%), and undetermined because of an incidence of more than 1 interaction in a single patient (653; 73.6%). From the 30 patients with major interactions...

Um estudo farmacoepidemiológico de interações medicamentosas em um hospital universitário brasileiro; A pharmacoepidemiologic study of drug interactions in a Brazilian teaching hospital

Cruciol-Souza, Joice Mara; Thomson, João Carlos
Fonte: Universidade de São Paulo. Faculdade de Medicina Publicador: Universidade de São Paulo. Faculdade de Medicina
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/01/2006 ENG
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INTRODUÇÃO: Embora as interações medicamentosas constituam uma pequena parcela das reações adversas a medicamentos, elas geralmente são previsíveis e às vezes podem ser evitadas. As prevalências de interações medicamentosas em hospitais são escassas no Brasil. OBJETIVO: Avaliar a prevalência de interações medicamentosas em prescrições hospitalares e seu significado clínico em pacientes de um hospital universitário brasileiro. MÉTODOS: Uma amostra de 1785 prescrições de enfermaria de adultos foi coletada de um total de 11.250 aviadas no período de janeiro a abril de 2004. As interações medicamentosas foram identificadas pelo Micromedex. Prontuários de pacientes com interações medicamentosas graves foram examinados por um médico e uma farmacêutica a busca de resultados laboratoriais que confirmassem a ocorrência da interação medicamentosa. RESULTADOS: As prescrições eram de pacientes masculinos (1089; 61%) em sua maioria. A idade média dos pacientes foi de 52,7 anos (DP=18,9; variação de 12 a 98 anos). Cada paciente recebeu em média 7 medicamentos (variando de 2 a 26). Ao menos 887 (49,7%) das prescrições continham interação medicamentosa. As prescrições continham interação medicamentosa classificadas como leve (55; 3.1%)...

Evaluation of Energetics-based Techniques for Proteome-Wide Studies of Protein-Ligand Binding Interactions

Geer, Michelle Ariel
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2015
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Detection and quantification of protein-ligand binding interactions is extremely important for understanding interactions that occur in biological systems. Since traditional techniques for characterizing these types of interactions cannot be performed in complex systems such as cell lysates, a series of energetics-based techniques that are capable of assessing protein stability and measuring ligand binding affinities have been developed to overcome some of the limitations of previous techniques. Now that the capabilities of the energetics-based techniques have been exhibited in model systems, the false-positive rates of the techniques, the range of biological questions to which the techniques can be addressed, and the use of the techniques to discover novel interactions in unknown systems remained to be shown. The Stability of Proteins from Rates of Oxidation (SPROX) technique and the Pulse Proteolysis (PP) technique were applied to a wide range of biological questions in both yeast and human cell lysates to evaluate the scope of these experimental workflows. The false-positive rate of iTRAQ-SPROX protein target discovery on orbitrap mass spectrometer systems was determined to be < 0.8 %. The iTRAQ-SPROX technique was successfully applied to the discovery of both known and novel protein-protein...

Thermodynamic modeling of protein interactions and phase behavior

Quang, Leigh
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
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Lenhoff, Abraham; Sandler, Stanley I.; Protein phase behavior encompasses the formation of dense phases, which include amorphous aggregates, gels, dense liquids, and crystals. The major solution variables that dictate the type of dense phase that is formed are pH, temperature, type of precipitant, precipitant concentration, and protein concentration. Because of the large parameter space and rich variety of phase transitions possible, protein phase behavior is a complex phenomenon. Fundamentally, macroscopic phase transitions are governed by the molecular interactions between proteins in solution. One promising way of quantifying protein-protein interactions and relating them to phase behavior is through the osmotic second virial coefficient B22, a dilute-solution property that characterizes two-particle interactions. The relationship of B22 to overall phase behavior of proteins is explored in this work. The goal of this thesis is to quantitatively relate protein-protein interactions to protein phase diagrams in order to develop predictive models of phase behavior under different solution conditions. A continuum-level approach is used initially to relate experimental B22 data and phase diagrams of proteins by appealing to existing thermodynamic models...

Host cell protein impurities and protein-protein interactions in downstream purification of monoclonal antibodies

Levy, Nicholas E.
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
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Lenhoff, Abraham M.; Monoclonal antibodies (mAbs) have become increasingly important as protein therapeutics over the last few decades. MAbs can be engineered to achieve high binding affinity to a wide array of desired biological targets. Despite having different therapeutic targets, mAbs have nearly identical amino acid sequences and biophysical properties. The high degree of similarity among different mAb products has led to the development of platform manufacturing processes in many companies. Downstream purification processes for mAbs are designed based on a platform process that is empirically tuned to optimize impurity removal for each new product. A more fundamental understanding of impurities and the product itself would provide insights into the rational design of efficient downstream processes. The first part of this thesis is focused on host cell protein (HCP) impurities, and the main objectives are to identify and characterize HCP impurities and their behavior in a typical downstream platform purification process. In protein A affinity chromatography - the capture step used in the majority of mAb platform purification processes - HCP impurities were found to associate to mAb products due to strongly attractive interactions. By coupling cross-interaction chromatography to proteomic analysis...

Analysis of potential interactions between warfarin and prescriptions in Estonian outpatients aged 50 years or more

Gavronski,Maia; Hartikainen,Sirpa; Zharkovsky,Alexander
Fonte: Pharmacy Practice (Internet) Publicador: Pharmacy Practice (Internet)
Tipo: info:eu-repo/semantics/article; journal article; info:eu-repo/semantics/publishedVersion Formato: text/html; application/pdf
Publicado em 01/03/2012 ENG
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In Estonia, warfarin is widely prescribed by general practitioners to prevent and treat thromboembolic diseases. To date, there has been no systematic analysis of the potential risk of warfarin interactions with other drugs in the outpatient population. Objective: The aim of the study was to analyze the incidence of potential interactions in prescription schemes in Estonia in a cohort of outpatients receiving warfarin treatment. Methods: The retrospective study population included 203,646 outpatients aged 50 years or older of whom 7,175 received warfarin therapy. Patients who had used at least one prescription drug for a minimum period of 7 days concomitantly with warfarin were analyzed. Potential drug interactions were analyzed using Epocrates online, Stockley´s Drug Interactions and domestic drug interaction databases. Results: The average number of drugs used concomitantly with warfarin was 4.8 (SD=1.9) (males: 4.7 SD=2.0, females: 4.9 SD=2.0). No potential interactions in treatment regimens were found in 38% of patients, one potential interaction was observed in 29% and two or more potential interactions were observed in 33% of patients. The mean number of all potential interactions was 1.2 per patient and about the same in men and women. Potential interactions were associated with the number of drugs. Warfarin-related interactions were detected in 57% of patients...