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Search Results: 1 - 10 of 304361 matches for " Raquel J. Vionette-Amaral "
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An Insight into the Transcriptome of the Digestive Tract of the Bloodsucking Bug, Rhodnius prolixus
José M. C. Ribeiro ,Fernando A. Genta,Marcos H. F. Sorgine,Raquel Logullo,Rafael D. Mesquita,Gabriela O. Paiva-Silva,David Majerowicz,Marcelo Medeiros,Leonardo Koerich,Walter R. Terra,Clélia Ferreira,André C. Pimentel,Paulo M. Bisch,Daniel C. Leite,Michelle M. P. Diniz,Jo?o Lídio da S. G. V. Junior,Manuela L. Da Silva,Ricardo N. Araujo,Ana Caroline P. Gandara,Sébastien Brosson,Didier Salmon,Sabrina Bousbata,Natalia González-Caballero,Ariel Mariano Silber,Michele Alves-Bezerra,Katia C. Gondim,Mário Alberto C. Silva-Neto,Georgia C. Atella,Helena Araujo,Felipe A. Dias,Carla Polycarpo,Raquel J. Vionette-Amaral,Patrícia Fampa,Ana Claudia A. Melo,Aparecida S. Tanaka,Carsten Balczun,José Henrique M. Oliveira,Renata L. S. Gon?alves,Cristiano Lazoski,Rolando Rivera-Pomar,Luis Diambra,Günter A. Schaub,Elói S. Garcia,Patrícia Azambuja,Glória R. C. Braz ,Pedro L. Oliveira
PLOS Neglected Tropical Diseases , 2014, DOI: 10.1371/journal.pntd.0002594
Abstract: The bloodsucking hemipteran Rhodnius prolixus is a vector of Chagas' disease, which affects 7–8 million people today in Latin America. In contrast to other hematophagous insects, the triatomine gut is compartmentalized into three segments that perform different functions during blood digestion. Here we report analysis of transcriptomes for each of the segments using pyrosequencing technology. Comparison of transcript frequency in digestive libraries with a whole-body library was used to evaluate expression levels. All classes of digestive enzymes were highly expressed, with a predominance of cysteine and aspartic proteinases, the latter showing a significant expansion through gene duplication. Although no protein digestion is known to occur in the anterior midgut (AM), protease transcripts were found, suggesting secretion as pro-enzymes, being possibly activated in the posterior midgut (PM). As expected, genes related to cytoskeleton, protein synthesis apparatus, protein traffic, and secretion were abundantly transcribed. Despite the absence of a chitinous peritrophic membrane in hemipterans - which have instead a lipidic perimicrovillar membrane lining over midgut epithelia - several gut-specific peritrophin transcripts were found, suggesting that these proteins perform functions other than being a structural component of the peritrophic membrane. Among immunity-related transcripts, while lysozymes and lectins were the most highly expressed, several genes belonging to the Toll pathway - found at low levels in the gut of most insects - were identified, contrasting with a low abundance of transcripts from IMD and STAT pathways. Analysis of transcripts related to lipid metabolism indicates that lipids play multiple roles, being a major energy source, a substrate for perimicrovillar membrane formation, and a source for hydrocarbons possibly to produce the wax layer of the hindgut. Transcripts related to amino acid metabolism showed an unanticipated priority for degradation of tyrosine, phenylalanine, and tryptophan. Analysis of transcripts related to signaling pathways suggested a role for MAP kinases, GTPases, and LKBP1/AMP kinases related to control of cell shape and polarity, possibly in connection with regulation of cell survival, response of pathogens and nutrients. Together, our findings present a new view of the triatomine digestive apparatus and will help us understand trypanosome interaction and allow insights into hemipteran metabolic adaptations to a blood-based diet.
Monitoring of the Parasite Load in the Digestive Tract of Rhodnius prolixus by Combined qPCR Analysis and Imaging Techniques Provides New Insights into the Trypanosome Life Cycle
Felipe de Almeida Dias?,Barbara Guerra?,Larissa Rezende Vieira?,Hugo Diego Perdomo?,Ana Caroline Paiva Gandara?,Raquel Juliana Vionette do Amaral,Renata Estebanez Vollú?,Suzete Araujo Oliveira Gomes?,Flavio Alves Lara?,Marcos Henrique Ferreira Sorgine
PLOS Neglected Tropical Diseases , 2015, DOI: 10.1371/journal.pntd.0004186
Abstract: Background Here we report the monitoring of the digestive tract colonization of Rhodnius prolixus by Trypanosoma cruzi using an accurate determination of the parasite load by qPCR coupled with fluorescence and bioluminescence imaging (BLI). These complementary methods revealed critical steps necessary for the parasite population to colonize the insect gut and establish vector infection. Methodology/Principal Findings qPCR analysis of the parasite load in the insect gut showed several limitations due mainly to the presence of digestive-derived products that are thought to degrade DNA and inhibit further the PCR reaction. We developed a real-time PCR strategy targeting the T. cruzi repetitive satellite DNA sequence using as internal standard for normalization, an exogenous heterologous DNA spiked into insect samples extract, to precisely quantify the parasite load in each segment of the insect gut (anterior midgut, AM, posterior midgut, PM, and hindgut, H). Using combined fluorescence microscopy and BLI imaging as well as qPCR analysis, we showed that during their journey through the insect digestive tract, most of the parasites are lysed in the AM during the first 24 hours independently of the gut microbiota. During this short period, live parasites move through the PM to establish the onset of infection. At days 3–4 post-infection (p.i.), the parasite population begins to colonize the H to reach a climax at day 7 p.i., which is maintained during the next two weeks. Remarkably, the fluctuation of the parasite number in H remains relatively stable over the two weeks after refeeding, while the populations residing in the AM and PM increases slightly and probably constitutes the reservoirs of dividing epimastigotes. Conclusions/Significance These data show that a tuned dynamic control of the population operates in the insect gut to maintain an equilibrium between non-dividing infective trypomastigote forms and dividing epimastigote forms of the parasite, which is crucial for vector competence.
Ciência e psicose: sobre o fim do vazio
Raquel Horta Fialho do Amaral
Psicologia Clínica , 2010, DOI: 10.1590/s0103-56652010000200033
Tannins Possessing Bacteriostatic Effect Impair Pseudomonas aeruginosa Adhesion and Biofilm Formation
Danielle S. Trentin, Denise B. Silva, Matheus W. Amaral, Karine R. Zimmer, Márcia V. Silva, Norberto P. Lopes, Raquel B. Giordani, Alexandre J. Macedo
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0066257
Abstract: Plants produce many compounds that are biologically active, either as part of their normal program of growth and development or in response to pathogen attack or stress. Traditionally, Anadenanthera colubrina, Commiphora leptophloeos and Myracrodruon urundeuva have been used by communities in the Brazilian Caatinga to treat several infectious diseases. The ability to impair bacterial adhesion represents an ideal strategy to combat bacterial pathogenesis, because of its importance in the early stages of the infectious process; thus, the search for anti-adherent compounds in plants is a very promising alternative. This study investigated the ability of stem-bark extracts from these three species to control the growth and prevent biofilm formation of Pseudomonas aeruginosa, an important opportunistic pathogen that adheres to surfaces and forms protective biofilms. A kinetic study (0–72 h) demonstrated that the growth of extract-treated bacteria was inhibited up to 9 h after incubation, suggesting a bacteriostatic activity. Transmission electron microscopy and fluorescence microscopy showed both viable and nonviable cells, indicating bacterial membrane damage; crystal violet assay and scanning electron microscopy demonstrated that treatment strongly inhibited biofilm formation during 6 and 24 h and that matrix production remained impaired even after growth was restored, at 24 and 48 h of incubation. Herein, we propose that the identified (condensed and hydrolyzable) tannins are able to inhibit biofilm formation via bacteriostatic properties, damaging the bacterial membrane and hindering matrix production. Our findings demonstrate the importance of this abundant class of Natural Products in higher plants against one of the most challenging issues in the hospital setting: biofilm resilience.
Expans?o urbana e turismo no litoral de Santa Catarina: o caso das microrregi?es de Itajaí e Florianópolis
Pereira, Raquel Maria Fontes do Amaral;
Intera??es (Campo Grande) , 2011, DOI: 10.1590/S1518-70122011000100010
Abstract: the unstable social tissues of rural brazilian area shows that ownership of the land itself has failed to develop. of the institutions that came into contact with before and after land ownership, religious organizations are most remembered. the article analyzed the role of religion in the social organization of the settlement by interviews with settlers. the trust has stood as the decisive action of restoring the fragile bonds in the studied community.
A constitui o do sujeito na pós-modernidade e o consumismo
Raquel Horta Fialho do Amaral Cougo
Revista Mal-estar e Subjetividade , 2011,
Abstract: El texto tiene como objetivo establecer relaciones entre el consumismo y los cambios ocurridos en el proceso de constitución del sujeto en la postmodernidad. Para eso, discurriré sobre el discurso del capitalista, ubicando en su estructura lógica una invitación a la felicidad plena a través de la adquisición de mercaderías. Veremos que será agregado un valor, un más de gozar, en palabras de Lacan, a los objetos de consumo y elevándolos al status de objeto a, que el discurso del capitalista hace escurrir su producción. Nuestras observaciones sobre el discurso del capitalista nos llevarán hasta un cuestionamiento acerca de los motivos que proporcionan una adherencia significativa a la propuesta de ese discurso en nuestra cultura. Para fundamentar una respuesta a esa pregunta, destacaré en la obra de Lacan la noción de sujeto del psicoanálisis subrayando la importancia de un punto imposible - la castración - para su estructuración. Ponderaré sobre el destino que el discurso de la ciencia reserva a este imposible tal como él es concebido por el psicoanálisis llegando hasta la noción de forclusión del sujeto. El texto aborda además el advenimiento del discurso científico en la contemporaneidad, así como los efectos de su incidencia en la constitución de los sujetos haciendo ver que estos se refieren a una remoción de los límites, en una lógica ilimitada y, por lo tanto, distinta de la castración. El trabajo termina con la observación de que los sujetos en la postmodernidad tenderán a dirigirse a promesas de satisfacción más intensas e ininterrumpidas, lo que justificaría el éxito de la invitación del discurso del capitalista al acceso inmediato a la felicidad.
Poliniza??o da aboboreira
Amaral, E.;Mitidieri, J.;
Anais da Escola Superior de Agricultura Luiz de Queiroz , 1966, DOI: 10.1590/S0071-12761966000100012
Abstract: the present paper deals with studies related to pollination of cucurbita pepo l. in the state of s. paulo, brazil. the following results were obtained: 1.° - the ratio of female flowers to male flowers openig at the same day was 1:17,7. 2.o - the opening of the female flowers and observed to occur before the sun rises. closing begins at 9 a.m. and is finished by 11 a. m. 3.° - with respect to pollinizating insects, trigona (trigona) ruficrus latr.) and apis, mellifera l. constitute the most important species. 4.° - due to the phenomenon of parthenocarpy no frutification was observed. 5.o - the sugar concentration of the nectar was observed to average 39,7% and 40,6%. 6.o - the pollination of cucurbita pepo l. is only by insects.
Rubem Amaral Júnior
Lumen et Virtus , 2010,
Abstract: This work deals with the identification of the forgotten 18th century European models of eight oil paintings on wood panels of Marian emblematic images on invocations of the Lauretan Litany in the Chapter Chapel at St. Francis Convent of the city of Salvador, Bahia, one of the richest complexes of colonial art in Brazil. It proceeds to compare the panels with their respective printed sources, i. e., the illustrations of the book Elogia Mariana (Augsburg, 1732), redrawn by Thomas Scheffler and engraved by Martin Engelbrecht after original engravings by 1 O presente trabalho foi apresentado originalmente no VI Congresso Internacional da Sociedade Espanhola de Emblemática, em Gandía (Espanha), em outubro de 2007, e publicado em Rafael García Mahíques e Vicent F. Zuriaga Senent (Eds.), Imagen y Cultura. La interpretación de las imágenes como Historia cultural, Valencia, Generalitat Valenciana, 2008, pp. 203-216 (Biblioteca Valenciana). 2 Rubem Amaral Jr., pesquisador independente, Embaixador aposentado, é bacharel em Direito pela Universidade Federal do Ceará, diplomado pelo Instituto Rio Branco e pelo Curso de Altos Estudos do Ministério das Rela es Exteriores. é sócio da Society for Emblem Studies de Glasgow e da Sociedade Espanhola de Emblemática de Cáceres (membro do Comitê Consultivo) e colaborador e membro do Comitê Científico de Imago. Revista de Emblemática e Cultura Visual, editada pela SEE. REVISTA LUMEN ET VIRTUSISSN 2177-2789 VOL. I No 3 DEZ/2010 Rubem Amaral Júnior 108 August Casimir Redel, stressing the great influence exerted by them on the Ibero-American religious baroque art and referring other examples of it. It quotes arguments developed by art historians about the possible authorship of the panels, which point towards the French Dominican friar Estev o do Loreto Joassar, who professed in Rio de Janeiro.
Rubem Amaral Júnior
Lumen et Virtus , 2011,
Abstract: – Taking as starting point the evidence of the modest participation of Portugal in emblematic at the time of the great development of that genre throughout Europe, especially in relation to emblem books, notwithstanding the undeniable influence exerted by foreign emblematic works upon Portuguese authors, the present article tries to carry out a survey of the titles produced in that country, original and in translation, both printed and manuscript, as well as of the secondary literature regarding them, and points out as the original and relevant Portuguese contribution to emblematics the use of emblem motifs in glazed tile panels, of which it seeks also to draw up an inventory.
Conceptual Problems in Cosmology
F. J. Amaral Vieira
Physics , 2011,
Abstract: In this essay a critical review of present conceptual problems in current cosmology is provided from a more philosophical point of view. In essence, a digression on how could philosophy help cosmologists in what is strictly their fundamental endeavor is presented. We start by recalling some examples of enduring confrontations among philosophers and physicists on what could be contributed by the formers to the day-time striving of the second ones. Then, a short review of the standard model Friedmann-Lema\^itre-Robertson-Walter (FLRW) of cosmology is given. It seems apparent that cosmology is living a golden age with the advent of observations of high precision. Nonetheless, a critical revisiting of the direction in which it should go on appears also needed, for misconcepts like "quantum backgrounds for cosmological classical settings" and "quantum gravity unification" have not been properly constructed up-to-date. Thus, knowledge-building in cosmology, more than in any other field, should begin with visions of the reality, then taking technical form whenever concepts and relations inbetween are translated into a mathematical structure. It is mandatory, therefore, that the meaning of such concepts be the same for all cosmologists, and that any relationship among all them be tested both logically as well as mathematically. In other words, the notorius feature of improbability of our universe, as is well-known, assures to cosmologists a priviledged degree of freedom for formulating interpretations and theories. However, at the same time, it demands for their formulations and conclusions to be considered in the light of data taken from astrophysical observations.
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