The focus of this research is on the optical measurement of uranyl in a solid matrix using fluorescence spectroscopy. Nanoporous silica-based materials were used to extract uranyl from contaminated soil and to enhance the fluorescence intensity and lifetime. The fluorescence lifetime and intensity of uranyl ions adsorbed on porous silica-based materials of varying pore size was measured as a function of pH and in the presence of fluoride. The feasibility of uranyl fluorescence detection on the top of soil by silica gel is carried out by four types of natural soil. The results show that the uranyl fluorescence intensity can be enhanced by approximately two orders of magnitude by the silica nanoporous matrix from pH 4-12 with the greatest enhancement occurring from pH 4-7. The enhanced fluorescence lifetime can be used in time-gated measurements to help minimize the influence of background environmental fluorophores. The pH and the fluoride variation causes different uranyl speciation and results in a peak shift in the fluorescence spectrum. The mechanism of the uranyl ion on the silica nanoporous matrix was studied through 15 different silica materials with different water content ratios and various concentrations of uranium on different silica structures. The result shows that the particle size, pore size, water content and uranyl concentration on silica surfaces are all important factors for optimizing the fluorescence intensity. The spacing between silica materials, either the pore inside materials or the space between particles, causes the variety of uranyl distribution on the material surface and changes the fluorescence performance. Also, X-Ray Photoelectron Spectroscopy (XPS) is used to identify the possible uranyl surface species on silica. The fluorescence emission spectra from silica materials and the XPS results are consistent with the presence of two different uranyl compounds. The specific surface area of silica materials plays an important role on uranyl adsorption mechanism. To further enhance the sensitivity, an optical ball lens was used to preferentially direct the fluorescence signal toward the excitation source in standoff measurements. The application of the ball lens was found to increase the detection distance up to 14 times.

This thesis was written to provide an alternative teaching model for an undergraduate theatre history class. The course design, utilizing the Problem-Based Learning educational model, aims to create a student-centered, experiential theatre history class. The first section explores the history and evolution of the theatre discipline in academia. These chapters examine the expansion and transformation of the theatre curriculum within the discipline and higher education. The second part examines the history and the methodologies of Problem-Based Learning. Based on the philosophy of educator John Dewey, PBL is considered to be a non-traditional method of teaching and learning that encourages the development of self-directed learning and the acquisition of knowledge through experiential education. The final section describes the actual course design. Included in this section are the educational objectives of the class, examples of problems, assessment methods, and an examination of potential challenges in the design.

2 Abstract Eukaryotic initiation factor 3 (eIF3) is a critical player involved in many steps of translation initiation, which ultimately result in the formation of the elongation competent 80S ribosome. With its 13 subunits (eIF3a - eIF3m) it is the largest and the most complex translation initiation factor composed of three mutually interconnected modules (i - iii), however, the role of individual subunits involved in its structural integrity and proper function is not fully explored. The eIF3e subunit was shown to be a part of the human eIF3 structural core and to help in the mRNA recruitment to the 43S pre-initiation complex by forming a molecular bridge between the 40S ribosomal subunit and the mRNA cap-binding complex. In this study, we employed siRNA-directed downregulation of eIF3e in HeLa cells and analysed its impact on the overall eIF3 integrity and function in vivo. The eIF3e knock-down (eIF3eK.D. ) led to the severe reduction of protein amounts of other three subunits (eIF3d, k and l), which together with the subunit eIF3c and e form module ii of the eIF3 complex. Remaining module i (composed of a, b, g and i) and iii (containing f, h and m) stayed partially bound perhaps thanks to a bridging effect of eIF3c, and showed reduced binding efficiency towards the 40S subunit compared to control...

This qualitative study employing ethnomethodology investigated whether previously employed African women between 50-59 years, termed near-old, turned to learning as a coping strategy after losing their jobs. Reflexive discussions, termed ‘herstories,’ were analysed. Whether the women experienced true crisis as a result of cessation from work, how they made meaning as they aged and to what extent retirement was a catalyst for learning formed the central lines of probing. The findings revealed that the near-old women did not consider the transition to old age a crisis. Crises in their experiences were more permanent and emotionally devastating. Meaning schemes and perspectives were transformed as they encountered unbearable work situations. Critical reflection on the situation led to action resulting in them exiting formal employment. There was strong evidence of self-directed and life-long learning. The women sought out new knowledge and skills in order to cope in the competitive work of consultancy. Instances of positive adult development attested to Mezirow’s theory of transformative learning and Brookfield’s reflective thinking. The study highlighted the need to use adult education strategies in order to promote critical reflection and to ‘conscientise’ older people about their deeply embedded beliefs that are often entrenched by their socialisation.

Cette recherche s’intéresse à l’usage de deux variables du français traditionnellement décrites comme phonologiques : la liaison et l’élision du schwa. Ces variables sont étudiées au cours d’interactions naturelles entre trois enfants et leurs parents respectifs. Plus précisément, l’objectif de cette thèse est de décrire les particularités du discours adressé à l’enfant (DAE) au niveau de l’usage des variables phonologiques et de mesurer leur impact sur l’émergence de la production de ces mêmes variables chez l’enfant. Après la présentation du cadre théorique d’analyse et de la méthodologie de recueil, de structuration et d’analyse des données, le travail de recherche s’organise en trois parties. La première étude basée sur corpus, descriptive, a deux principaux objectifs. Dans un premier temps, il s’agit de mesurer à quelle variation les jeunes enfants sont exposés au domicile familial. Ensuite, le but est de confronter les résultats des études précédentes sur l’acquisition de la liaison, principalement obtenus à partir de tâches expérimentales, à des données issues de corpus denses d’interactions parent-enfant. Cette étude a notamment permis de relever l’influence de facteurs liés à l’usage, comme la fréquence, sur l’emploi des variables phonologiques. La seconde étude se focalise sur les caractéristiques du DAE. Les résultats présentés démontrent notamment que l’usage des variables phonologiques est modulé en DAE, et ce essentiellement à un stade précoce. Cette modulation s’atténue ensuite au cours du développement linguistique des jeunes sujets. La dernière étude de ce travail de recherche permet de mettre en relation les productions enfantines et parentales. Il apparaît que le développement de la variation phonologique va dans le sens des hypothèses émises par les modèles basés sur l’usage : la variation phonologique est à un stade précoce mémorisée à l’intérieur de constructions spécifiques, particulièrement fréquentes et saillantes dans le DAE. Celles-ci vont ensuite s’abstraire et entrer en concurrence au cours du développement, ces deux phénomènes étant particulièrement sensibles aux facteurs d’usage, notamment la fréquence d’emploi des types et des formes linguistiques. / This study deals with the usage of two French linguistic variables liaison and elision, which are traditionally described as phonological variables. They are studied during natural interactions between three children and their parents. More precisely, the aim of this thesis is to describe the specificities of the child directed speech (CDS) concerning the usage of liaison and elision to measure their impact on the emergence of these phonological variables in the speech of the children. After the presentation of the theoretical context of the study (Usage-Based Models and Construction Grammar) and the methodology used to collect, structure, and analyse the data, the research is divided into three analysis sections. The aim of the first corpus based study, a descriptive one, is twofold. The first objective is to describe the variation to which children are exposed at home. A second objective is to compare the results of previous studies on liaison acquisition, obtained mainly from experimental tasks, with data extracted from dense corpora collected during natural interactions between the children and their parents. In particular, this study shows that usage factors, including the frequency of items, influence the production of phonological variables. The second study focuses on the specificities of CDS. The results show that the usage of phonological variables is modulated in CDS, essentially at an early stage of language acquisition. Then, this modulation attenuates during the child’s development. The aim of the third study is to connect parent’s productions and children’s productions. It appears that the results concerning the development of phonological variation are in step with the assumptions provided by the usage-based models: at an early stage, the variation is memorized into specific constructions, particularly salient and frequent in CDS. Then, these constructions are abstracted and enter into competition with each other during the course of language development. The children’s productions show that these two phenomena are especially sensitive to usage factors, including type and token frequency.

La L-asparaginase est une enzyme d’intérêt thérapeutique pour le traitement des leucémies aigües lymphoblastiques participant à l’hydrolyse de son substrat naturel L-asparagine conduisant à l’apoptose des cellules cancéreuses. À ce jour, la L-asparaginase d’origine bactérienne fait partie intégrante des formulations car possédant des activités catalytiques élevées mais provoquant de nombreux effets secondaires liés à une immunogénicité. Trois enzymes avec une activité Lasparaginase produites chez l’homme ont été découvertes récemment mais possèdent des activités catalytiques qui sont 1000 à 2000 fois inférieures aux enzymes d’origine bactérienne. Augmenter l’activité catalytique de ces enzymes par évolution dirigée pourraient permettre leurs utilisations en thérapeutique en plus de potentiellement participer à la réduction de l’immunogénicité chez les patients. Ces travaux de doctorat décrivent le développement d’outils pour l’expression etla détection de l’activité L-asparaginase à l’échelle d’une cellule individuelle. La L-asparaginase d’E. coli, utilisée en thérapeutique, a servi de référence et a permis de démontrer que le test AUR est le plus adapté pour la mesure de l’activité en microfluidique. L’expression de l’enzyme à partir de différents vecteurs d’expression a montré que l’expression périplasmique semble la plus adaptée pour le ciblage permettant un bon rendement et une bonne accessibilité pour le substrat. La viabilité des cellules à l’issu des mesures a été aussi démontrée. Ces outils pourront être directement utilisés pour le criblage de banques de mutants de L-asparaginase d’origine humaine en microfluidique. Les propriétés de la L-asparaginase ont aussi été utilisées pour démontrer la potentielle utilisation de billes de silice en tant que biocatalyseurs où sont confinées des bactéries. Ces billes sont des excellents supports pour la croissance de microorganismes qui peuvent rester viables au-delà d’une semaine. L’expression d’enzymes peut être induite et l’activité catalytique être aisément contrôlée en faisant varier la concentration bactérienne au sein du matériau. La combinaison de différentes populations bactériennes offre la possibilité d’effectuer des réactions en cascade. Le recyclage de ces billes pour différents cycles de réactions a également été démontré. Ces matériaux bioactifs peuvent avoir de nombreuses applications dans le domaine des biotechnologies. / L-asparaginase is an enzyme of therapeutic value for the treatment of acute lymphoblastic leukemia. Ths enzyme catalyzes the hydrolysis of L-asparagine conducting to apoptosis of cancer cells. To date, L-asparaginase of bacterial origine is used in the treatments due to high catalytic activities but causing a number of side effects linked with an immunogenicity. The human produces three enzymes with L-asparaginase activity but their catalytic activities are 1000 to 2000 times lower than the bacterial enzymes. Increase the catalytic activity of these enzymes by directed evolution could allow their uses in therapeutic in addition to potentially reduce immunogenicity in patients. This PhD work describes the development of tools for expression and detection of L-asparaginase at the single cell level for their applications in the screening of human L-asparaginase libraries in microfluidic. E. coli L-asparaginase, used in therapy, served as a reference and allowed to demonstrate that AUR assay is most suitable for measuring activity in microfluidic. Expression of the enzyme from different expression vectors showed that the periplasmic expression seems to be the most successful for screening enabling a good yield and good accessibility for the substrate. The viability of the cells following the measures has been shown. These tools might be used for the screening of mutants libraries of human L-asparaginases in microfluidic. The properties of L-asparaginase were also used to demonstrate the potential use of silica beads as biocatalysts in which bacteria are confined. These beads are excellent supports for the growth of microorganisms which may remain viable beyond one week. The expression of the enzymes may be induced and the catalytic activity can be reliably controlled by varying the concentration of bacteria within the material. The combination of various bacterial populations provides the possibility to carry out cascades reactions. The recycling of these beads for several cycles of reactions was also demonstrated. These bioactive materials have many potential applications in the field of biotechnologies.

Este estudo é uma pesquisa do tipo exploratório-descritiva que objetivou identificar como os alunos de um Curso Técnico de Enfermagem de uma Escola de Educação Profissional na cidade de São Paulo avaliam a estratégia de ensino estudo dirigido aplicada na Disciplina Saúde do Adulto. A população constituiu-se de 17 alunos e a amostragem 14, com formação básica profissional de auxiliar de enfermagem que concluíram o Curso de Habilitação Profissional de Técnico de Enfermagem. O instrumento de coleta de dados utilizado foi um questionário, contendo 11 questões, aplicado em um único momento, após autorização do Comitê de Ética da mantenedora da Escola e da diretoria da Instituição, os preceitos éticos que envolvem os sujeitos participantes foram seguidos.A metodologia para análise dos resultados ocorreu de acordo com a natureza das questões, quantificados em porcentuais simples e as demais analisadas pelo conteúdo de acordo com a proposta de Bardin (1977). Os resultados foram apresentados em quadros, tabelas e gráficos. A análise dos resultados foi realizada à luz do referencial de Freire (2000). Os alunos conceituaram como boa (86,0%) e excelente (14,0%) a estratégia utilizada, e foram identificadas 83 (100%) unidades semânticas na análise das respostas que justificaram os conceitos, sendo categorizados em: Vantagens, 44 (53,0%); Não “Legal", 13 (16,0%); Dificuldades, 6 (7,0%); Sentimentos, 10 (12,0%) e Sugestões, 10 (12,0%). Os sujeitos aferiram notas de 1 a 4 em nível crescente de aceitação aos propósitos didático-pedagógicos, conferidos ao estudo dirigido inspirado em Nérici (1992), os proósitos didático-pedagógicos receberam maiores notas que permitem o desenvolvimento de temas de interesse do aluno; estimulam o prazer para estudar e incentivam o aluno a ser o sujeito de seu aprendizado. Considerando que o estudo dirigido foi usado dentro de uma pedagogia interacionista, dialética, materialista e progressista, concluiu-se que os alunos justificaram o conceito atribuído ao estudo dirigido de forma competente e responsável, contribuindo para a melhoria dos resultados do processo ensino-aprendizado em sala de aula, trazendo importantes reflexões docentes para o desenvolvimento de habilidades e competências no uso do estudo dirigido. / This is a descriptive exploratory study that aimed to identify how students attending a practical nurse course at a vocational school in the city of São Paulo evaluate the teaching strategy of direct study applied to the course Health of Adults. The population was comprised by seventeen students and the sample by fourteen of them. Students had a basic professional training as nursing assistants, and had finished the practical nurse course by the time the evaluation of direct study was carried out. A questionnaire with twelve questions was used as the tool to collect data. It was applied once after the authorization of the Ethics Committee of the entity that supports the school and the school management team. Ethical concepts with regards to the subjects were followed. Different methodology was applied to study the results based on the type of questions: quantified in simple percentages or content analysis, according to what was proposed by Laurence Bardin (1977). Results are presented in charts, tables and graphs. Result analysis was performed according to Freire (2000). Students rated the strategy used as good (86%) and excellent (14%). Eighty-three (100%) semantic units were identified to examine the answers that justified the rates. The units were separated in cathegories: advantages, 44 (53%); not “nice", 13 (16%); difficulties, 6 (7%); feelings, 10 (12%), and suggestions, 10 (12%). Subjects graded the didatic educational proposals from 1 to 4, in crescent order of acceptance regarding directed study as proposed by Nérici (1992); the educational proposals that received higher rates were those that allowed the development of issues that interest the student, that increases the pleasure in studying, and that encourage the student to be the subject of his learning process. Considering that directed study was used in a progressive materialist dialectical interactive educational style, we conclude that the students justify the concept given to directed study in a competent and responsible manner, contributing to the improvement of results of learning-teaching process in the classroom, and raising important thoughts on teacher regarding development of skills and competences to use directed study.

Os programas de computador têm apoiado o estudo de sistemas biomédicos em que um volume considerável de dados são empregados. Na biomecânica, a análise das influências entre as articulações pode melhorar o conhecimento das lesões relacionadas à corrida associadas ao uso excessivo durante a atividade de corrida. Compreender os padrões de interação entre diferentes articulações anatômicas, durante o movimento, pode contribuir para o aprimoramento de programas de treinamento, reabilitação e prevenção a lesões. Neste trabalho, um software personalizado foi desenvolvido para implementar a Coerência Parcial Direcionada (PDC), uma abordagem no domínio da freqüência da Causalidade de Granger (GC), adequado às especificidades da fisioterapia. Com entradas independentes e padronizadas, modularização e parametrização, as rotinas investigaram a direção de interação entre diferentes canais, registrando e salvando arquivos intermediários. Separados nos três planos anatômicos, sagital, frontal e transverso, foram utilizados dados cinemáticos para analisar as interações entre tornozelo, joelho, quadril, pelve e tronco durante a corrida. Três modificações de técnica de corrida foram abordadas: com aterrissagem iniciada com o antepé, com aumento de 10% na taxa de passo e com aumento de flexão de tronco, além da habitual. As análises foram realizadas para o ciclo completo (apoio e balanço) e com separação da fase de apoio, e revelaram que essas duas estratégias de processamento são complementares. Comparando as influências proximal e distal, os procedimentos sugeriram uma predominância das interações proximal a distal, mostrando uma origem central de movimentos. Dessa forma, destaca-se a relevância em controlar e fortalecer tronco e quadril para a minimização de lesões. Considerando os resultados e a oportunidade de configuração, o software pode ser empregado para estudar outras articulações e aplicações, bem como evoluir para um sistema automatizado de apoio à decisão. / Computer programs have supported the study of biomedical systems in which a considerable amount of data is employed. In biomechanics, analysis of influences between joints can improve the knowledge of the Running-Related-Injuries (RRI) associated to overuse during running activity. Understanding the patterns of interaction among anatomical joints during movement can contribute to the improvement of training, rehabilitation and injury prevention programs. In this work, a customized software was developed to implement Partial Directed Coherence (PDC), an approach in the frequency domain of Granger Causality (GC), adapted to the physical therapy specificities. With independent and standardized inputs, modularization and parameterization, the routines investigated the interaction direction between different channels, logging and saving intermediate files. Separated in the three anatomical planes, sagittal, frontal and transverse, kinematic data were employed to analyze the interactions between ankle, knee, hip, pelvis and trunk during running. Three running technique modifications were addressed: forefoot strike landing pattern, increasing 10% of the step rate and increasing trunk flexion, in addition to usual running. The analyzes were performed for the complete cycle (stance and swing) and with separation of the stance phase, and revealed that these two processing strategies are complementary. Comparing proximal and distal influences, procedures suggested a predominance of proximal to distal interactions, showing a central origin of movements. In this way, the importance of controlling and strengthening trunk and hip to minimize injuries is highlighted. Considering the results and the processing configuration opportunity, the software can be employed to study other joints and applications, as well as evolve to an automated decision support system.

O notável desenvolvimento da indústria eletrônica observado nos últimos tempos tem permitido aplicações de conjuntos integrados de sensores em ambientes sem fio, conhecidos por wireless sensor networks (WSN), que passam por sensoriamento de processos industriais, ambientes tóxicos, projetos militares de monitoração de variáveis de segurança, até observação de fenômenos físicos naturais. Uma das principais especificações de uma rede WSN, o consumo de energia afeta diretamente a capacidade e tempo de vida útil do sistema, pois, na maioria dos casos, seus módulos possuem baterias independentes e sua substituição nem sempre é tarefa simples. Motivado pela necessidade de oferecer robustez e economia de energia nas redes WSN, o protocolo difusão direcionada se baseia na centralização de dados e a identificação de seus módulos é feita por meio de pares valor-atributo. Sua estrutura permite a adição de componentes de software que podem atuar na análise e modificação dos dados recebidos com o objetivo de alterar o protocolo original. O objetivo principal deste trabalho é investigar um método para otimização do uso de energia disponível em redes WSN com intuito de prolongar seu tempo de vida útil. O metódo consiste em analisar os valores das energias atribuídas aos módulos componentes da rede por meio de incorporação de um algoritmo de rotas baseado em energia ao protocolo difusão direcionada. Comparações de desempenho da rede em relação ao seu tempo de vida e energia dos módulos são realizadas utilizando o simulador NS-2. As simulações feitas em diversos cenários indicaram melhoria de desempenho em relação ao protocolo difusão direcionada original. Os cenários onde o protocolo original foi alterado apresentaram um número maior de rotas descobertas e possibilitaram um aumento de pelo menos 22% no tempo de vida da rede, em relação ao protocolo original. / The notable development of electronic industry in the last years allows the implementation of sensor integrated circuits in wireless environments, known as wireless sensor networks (WSN), which leads to industrial process sensing, toxic environments, military security monitor projects and natural physical phenomenon. As one of the main specifications of a WSN network, the energy consumption directly affects the capacity and the system useful lifetime, since most of the time its modules have independent batteries and their substitution is not always a simple task. Motivated by the need of offering robustness and energy economy for WSN networks, the directed diffusion protocol is data-centric based and its modules identification is made by attribute-value pairs. The directed diffusion structure enables the addition of software components which can act on the analysis and modification of received data with the objective of changing the original protocol. The main objective of this work is to investigate a method for optimization of available energy on WSN networks with the intention of increasing its useful lifetime. The method consists on analyzing the energy values attributed to the component modules of the network by incorporating an energy-based routing algorithm to directed diffusion protocol. Performance comparisons of the network related to its lifetime and modules energy are developed using the NS-2 simulator. Simulations performed in several scenarios indicated a better performance in relation to the original directed diffusion protocol. The scenarios where the original protocol was changed had larger number of discovered routes and allowed a rising of at least 22% on network lifetime, in relation to the original protocol.

As fosfolipases A2 (PLA2s, ou fosfatidil-acil hidrolases EC 3.1.1.4) catalisam especificamente a hidrólise das ligações ácido-éster na posição sn-2 de glicerofosfolipídios liberando, como produto da catálise, ácidos graxos e lisofosfolipídio. São encontradas em plantas, mamíferos e em veneno de animais vertebrados e invertebrados e estão envolvidas em uma ampla variedade de processos fisiológicos. A fosfolipase A2 secretada humana do grupo IIA (hsPLA2 gIIA) é uma proteína de fase aguda da resposta imunológica, pois sua expressão é induzida por endotoxinas e citocinas via processos autócrinos e/ou parácrinos durante processos inflamatórios de relevância clínica. A hsPLA2 gIIA mostra efeito bactericida contra infecção por Staphylococcus aureus, e tem marcada preferência por fosfolipídios aniônicos tais como fosfatidilglicerol (PG) encontrados em membranas bacterianas. Uma grande variedade de inibidores de PLA2 do grupo IIA foi descrita na literatura, incluindo substâncias polianiônicas que atuam contra os efeitos inflamatórios destas enzimas. Suramina é um derivado de naftiluréia polissulfonado que recentemente mostrou ligação com os resíduos catiônicos no sítio de reconhecimento interfacial de Bothropstoxina-I (BthTX-I), uma PLA2-Lys49 isolada do veneno de Bothrops jararacussu, inibindo a atividade miotóxica da proteína. Devido ao tipo de interação diferenciada da suramina com BthTX-I em relação aos inibidores competitivos de PLA2, nós avaliamos a especificidade de ligação da suramina na hsPLA2 gIIA como um modelo para estudar este novo tipo de inibidor de PLA2s. O efeito da suramina nas atividades biológicas e de membranas artificiais da hsPLA2 gIIA foi avaliado. A suramina aboliu tanto a atividade hidrolítica da hsPLA2 gIIA quanto a atividade de danificação de membranas artificiais Ca2+ independente. Embora a suramina não tenha inibido a atividade bactericida da hsPLA2 gIIA contra a linhagem Micrococcus luteus, a ativação de macrófagos foi abolida pela mesma de maneira dependente de hidrólise. Além disso, técnicas de simulação de dinâmica molecular, calorimetria de titulação isotérmica e mutagênese sítio dirigida foram utilizadas para mapear os sítios de ligação da suramina na proteína. A interação da suramina com a hsPLA2 gIIA resultou de interações eletrostáticas entre grupos sulfonados com cadeias laterais de aminoácidos da região do sítio ativo e dos resíduos em torno das posições 15 e 116 localizados, respectivamente, na N- e Cterminal. Portanto, estes resultados permitem sugerir que a suramina pode atuar como inibidor de sPLA2s / Suramin is a polysulphonated napthylurea used as an antiprotozoal drug that presents inhibitory activity against a broad range of enzymes. We have evaluated the effect of suramin against the artificial and biological activities of the secreted human group IIA phospholipase A2 (hsPLA2 gIIA), a protein involved in inflammatory processes. To map the suramin binding sites on the hsPLA2 gIIA, proteins with mutations in the active site region and in the protein surface that makes contact with the phospholipids membrane were expressed in E. coli and refolded from inclusion bodies. The activation of macrophage cell line RAW 264.7 by hsPLA2 gIIA was monitored by nitric oxide release, and bactericidal activity of the protein against Micrococcus luteus was evaluated by colony counting and by flow cytometry. The hydrolytic activity of the hsPLA2 gIIA against lipossomes composed of a mixture of dioleoylphosphatidylcholine/dioleoylphosphatidylglycerol (DOPC/DOPG) was inhibited by a concentration of 100 nM suramin. The activation of macrophages by hsPLA2 gIIA was abolished at protein/suramin molar ratios where the hydrolytic activity of the enzyme was inhibited. In contrast, both the bactericidal activity of hsPLA2 gIIA against Micrococcus luteus and permeabilization of the bacterial inner membrane were unaffected by suramin concentrations up to 50 M. The affinity of interaction of the suramin with hsPLA2 gIIA was evaluated by suramine fluorescence and the mutants K15A, K38A, R54A and K123A presented a reduced affinity. The binding of the suramin/hsPLA2 gIIA complex was investigated by molecular dynamics simulations, which indicated two conformations of the bound inhibitor, which involve cationic amino-acid side chains in the active-site region and residues around positions 15 and 116 located in the N- and C-termini respectively in the substrate recognition surface. These results were correlated with isothermal titration calorimetry data, which demonstrated 2.7 suramin-binding sites on the hsPLA2 gIIA. These results suggested that suramin represents a novel class of phospholipase A2 inhibitor