Perfil de Expresión Génica en Hipocampo de Ratones Idosos Tratados con Psidium cattleyanum

El objetivo de éste trabajo fue evaluar el efecto de la administración oral prolongada (1000 mg/kg, 8 meses) del extracto de Psidium cattleyanum Sabine (Myrtaceae) en el perfil de la expresión génica en hipocampo de ratones idosos (Swiss). Después de 8 meses de suplementacion, no se detectaron efectos tóxicos en los animales tratados con relación al grupo control. Los genes con expresión diferencial incluyen, genes que codifican proteínas relacionadas con procesos de señalización, transcripción, metabolismo, así como genes con función desconocida. Los resultados demuestran la importancia de los microarray como herramienta para el estudio del mecanismo de acción de los compuestos fitoquímicos

A Formação de Redes de Empresas: o Caso da Região Central do Rio Grande do Sul – RS

O presente trabalho  aborda o tema sobre o  processo de formação  de redes  entre Pequenas e Médias Empresas (PMEs). A partir de evidências teóricas, a questão da pesquisa confrontada foi compreender como ocorre a formação de redes interorganizacionais horizontais. A pesquisa estudou e qualificou os fatores subjacentes à formação de redes horizontais de cooperação. No estágio de formação da rede, são analisados os fatores de motivação, escolha do grupo, papel da liderança e a confiança. Para verificar a experiência da formação das redes, o delineamento da pesquisa é de um estudo exploratório, com abordagem quantitativa e qualitativa. A pesquisa empírica foi conduzida por meio de entrevistas com os primeiros e atuais presidentes de nove redes horizontais na Região Central do Estado do Rio Grande do Sul (RS). Também, para melhor entender o fenômeno e aprofundar o estudo aplicou-se um questionário junto aos empresários fundadores das redes. Os resultados da pesquisa evidenciam que as pressões contingenciais, como a concorrência, a dificuldade de obter recursos tangíveis e intangíveis, a falta de crédito, o baixo volume de negócio, exercem influência na motivação para formar redes, que buscam complementaridade de conhecimentos e resultados econômicos

Immune reactivity to Trypanosoma cruzi chimeric proteins for Chagas disease diagnosis in immigrants living in a non-endemic setting

Chagas disease; Chimeric antigens; Trypanosoma cruziMalaltia de Chagas; Antígens quimèrics; Trypanosoma cruziEnfermedad de Chagas; Antígenos quiméricos; Trypanosoma cruziBACKGROUND: Chronic Chagas Disease (CD) diagnosis is based on serological methods employing crude, semipurified or recombinant antigens, which may result in low sensitivity or cross-reactivity. To reduce these restrictions, we developed a strategy involving use of molecules containing repetitive fragments of Trypanosoma cruzi conserved proteins. Diagnostic performance of IBMP-8.1 and IBMP-8.4 chimeric antigens (Molecular Biology Institute of Paraná - IBMP in Portuguese acronym) was assessed to diagnose T. cruzi-infected and non-infected immigrants living in Barcelona (Spain), a non-endemic setting for Chagas disease. METHODS: Reactivity of IBMP-8.1 and IBMP-8.4 was assessed using an in-house automated ELISA with 347 positive and 331 negative individuals to Chagas disease. Antigenic cross-reactivity was measured with sera samples from pregnant women with Toxoplasma gondii (n = 98) and Zika virus (n = 75) antibodies. RESULTS: The area under the curve values was 1 and 0.99 for the IBMP-8.1 and IBMP-8.4 proteins, respectively, demonstrating excellent diagnostic accuracy. The reactivity index was higher for IBMP-8.1 than IBMP-8.4 in positive samples and no significant difference in reactivity index was observed in negative samples. Sensitivity ranged from 99.4% for IBMP-8.1 to 99.1% for IBMP-8.4 and was not statistically different. Specificity for IBMP-8.1 reached 100 and 99.7% for IBMP-8.4, both nearly 100% accurate. No antigenic cross-reactivity was observed and reactivity index was similar to that for negative Chagas disease individuals. CONCLUSIONS: Our results showed an outstanding performance of IBMP-8.1 and IBMP-8.4 chimeric antigens by ELISA and suggest both chimeric antigens could also be used for Chagas disease diagnosis in immigrants living in non-endemic settings

Pi3k Inhibition Synergizes With Glucocorticoids But Antagonizes With Methotrexate In T-cell Acute Lymphoblastic Leukemia.

The PI3K pathway is frequently hyperactivated in primary T-cell acute lymphoblastic leukemia (T-ALL) cells. Activation of the PI3K pathway has been suggested as one mechanism of glucocorticoid resistance in T-ALL, and patients harboring mutations in the PI3K negative regulator PTEN may be at increased risk of induction failure and relapse. By gene expression microarray analysis of T-ALL cells treated with the PI3K inhibitor AS605240, we identified Myc as a prominent downstream target of the PI3K pathway. A significant association was found between the AS605240 gene expression signature and that of glucocorticoid resistance and relapse in T-ALL. AS605240 showed anti-leukemic activity and strong synergism with glucocorticoids both in vitro and in a NOD/SCID xenograft model of T-ALL. In contrast, PI3K inhibition showed antagonism with methotrexate and daunorubicin, drugs that preferentially target dividing cells. This antagonistic interaction, however, could be circumvented by the use of correct drug scheduling schemes. Our data indicate the potential benefits and difficulties for the incorporation of PI3K inhibitors in T-ALL therapy.613105-1311

Genotype variation in rice (Oryza sativa L.) tolerance to Fe toxicity might be linked to root cell wall lignification

Iron (Fe) is an essential element to plants, but can be harmful if accumulated to toxic concentrations. Fe toxicity can be a major nutritional disorder in rice (Oryza sativa) when cultivated under waterlogged conditions, as a result of excessive Fe solubilization of in the soil. However, little is known about the basis of Fe toxicity and tolerance at both physiological and molecular level. To identify mechanisms and potential candidate genes for Fe tolerance in rice, we comparatively analyzed the effects of excess Fe on two cultivars with distinct tolerance to Fe toxicity, EPAGRI 108 (tolerant) and BR-IRGA 409 (susceptible). After excess Fe treatment, BR-IRGA 409 plants showed reduced biomass and photosynthetic parameters, compared to EPAGRI 108. EPAGRI 108 plants accumulated lower amounts of Fe in both shoots and roots compared to BR-IRGA 409. We conducted transcriptomic analyses of roots from susceptible and tolerant plants under control and excess Fe conditions. We found 423 up-regulated and 92 down-regulated genes in the susceptible cultivar, and 42 up-regulated and 305 down-regulated genes in the tolerant one. We observed striking differences in root gene expression profiles following exposure to excess Fe: the two cultivars showed no genes regulated in the same way (up or down in both), and 264 genes were oppositely regulated in both cultivars. Plants from the susceptible cultivar showed down-regulation of known Fe uptake-related genes, indicating that plants are actively decreasing Fe acquisition. On the other hand, plants from the tolerant cultivar showed up-regulation of genes involved in root cell wall biosynthesis and lignification. We confirmed that the tolerant cultivar has increased lignification in the outer layers of the cortex and in the vascular bundle compared to the susceptible cultivar, suggesting that the capacity to avoid excessive Fe uptake could rely in root cell wall remodeling. Moreover, we showed that increased lignin concentrations in roots might be linked to Fe tolerance in other rice cultivars, suggesting that a similar mechanism might operate in multiple genotypes. Our results indicate that changes in root cell wall and Fe permeability might be related to Fe toxicity tolerance in rice natural variation

Performance of recombinant chimeric proteins in the serological diagnosis of Trypanosoma cruzi infection in dogs.

Background: Dogs are considered sentinels in areas of Trypanosoma cruzi transmission risk to humans. ELISA is generally the method of choice for diagnosing T. cruzi exposure in dogs, but its performance substantially depends on the antigenic matrix employed. In previous studies, our group has developed four chimeric antigens (IBMP-8.1, 8.2, 8.3, and 8.4) and evaluated their potential for diagnosing T. cruzi exposure in humans. For human sera, these chimeric antigens presented superior diagnostic performances as compared to commercial tests available in Brazil, Spain, and Argentina. Therefore, in this study we have evaluated the potential of these antigenic proteins for detection of anti-T. cruzi IgG antibodies in dog sera. Methodology/Principal findings: The IBMP-ELISA assays were optimized by checkerboard titration. Subsequently, the diagnostic potential was validated through analysis of ROC curves and the performance of the tests was determined using double entry tables. Cross-reactivity was also evaluated for babesiosis, ehrlichiosis, dirofilariosis, anaplasmosis, and visceral leishmaniasis. Best performance was shown by IBMP-8.3 and IBMP-8.4, although all four antigens demonstrated a high diagnostic performance with 46 positive and 149 negative samples tested. IBMP-8.3 demonstrated 100% sensitivity, followed by IBMP-8.4 (96.7?100%), IBMP-8.2 (73.3?87.5%), and IBMP-8.1 (50?100%). The highest specificities were achieved with IBMP-8.2 (100%) and IBMP-8.4 (100%), followed by IBMP-8.3 (96.7?97.5%) and IBMP 8.1 (89.1?100%). Conclusions/Significance: The use of chimeric antigenic matrices in immunoassays for anti-T. cruzi IgG antibody detection in sera of infected dogs was shown to be a promising tool for veterinary diagnosis and epidemiological studies. The chimeric antigens used in this work allowed also to overcome the common hurdles related to serodiagnosis of T. cruzi infection, especially regarding variation of efficiency parameters according to different strains and cross-reactivity with other infectious diseases

In silico analysis of amino acid variation in human respiratory Syncytial virus: insights into immunodiagnostics

Submitted by Manoel Barata ([email protected]) on 2018-02-09T15:58:00Z No. of bitstreams: 1 ZanchinInSil.pdf: 4932859 bytes, checksum: d66e391fe69434a3a2b08d848d6f169c (MD5)Approved for entry into archive by Manoel Barata ([email protected]) on 2018-02-26T19:12:12Z (GMT) No. of bitstreams: 1 ZanchinInSil.pdf: 4932859 bytes, checksum: d66e391fe69434a3a2b08d848d6f169c (MD5)Made available in DSpace on 2018-02-26T19:12:12Z (GMT). No. of bitstreams: 1 ZanchinInSil.pdf: 4932859 bytes, checksum: d66e391fe69434a3a2b08d848d6f169c (MD5) Previous issue date: 2017Fundação Oswaldo Cruz. Instituto Carlos Chagas. Laboratório de Genômica Funcional. Curitiba, PR, Brasil / Instituto de Biologia Molecular do Paraná. Curitiba, PR, Brasil / Universidade Federal do Paraná. Programa de Pós-Graduação em Biologia Celular e Molecular. Curitiba, PR, Brasil.Fundação Oswaldo Cruz. Instituto Carlos Chagas. Laboratório de Genômica Funcional. Curitiba, PR, Brasil / Universidade Federal do Paraná. Programa de Pós-Graduação em Biologia Celular e Molecular. Curitiba, PR, Brasil.Fundação Oswaldo Cruz. Instituto Carlos Chagas. Laboratório de Genômica Funcional. Curitiba, PR, Brasil / Instituto de Biologia Molecular do Paraná. Curitiba, PR, Brasil.The highly contagious nature of human respiratory syncytial virus (HRSV) and the gravity of its infection in newborns and vulnerable adults pose a serious public health problem. Thus, a rapid and sensitive diagnostic test for viral detection that can be implemented upon the first appearance of symptoms is needed. The genetic variation of the virus must be considered for immunodiagnostic purposes.This paper has the objectiv of to analyse HRSV genetic variation and discuss the possible consequences for capture immunoassay development. We performed a wide analysis of N, F and G protein variation based on the HRSV sequences currently available in the GenBank database. We also evaluated their similarity with homologous proteins from other viruses. It found that the mean amino acid divergences for the N, F, and G proteins between HRSV-A and HRSV-B were determined to be approximately 4%, 10% and 47%, respectively. Due to their high conservation, assays based on the full-length N and F proteins may not distinguish HRSV from human metapneumovirus and other Mononegavirales viruses, and the full-length G protein would most likely produce false negative results due to its high divergence. How main conclusions, we have identified specific regions in each of these three proteins that have higher potential to produce specific results, and their combined utilisation should be considered for immunoassay development

Structural characterization of the Internal Transcribed Spacer 2 (ITS2) of the ribosomal DNA (rDNA) cluster in calyptratae (Diptera: Schizophora) and its implications for molecular phylogenetic analyses.

Submitted by Luciane Willcox ([email protected]) on 2016-09-30T18:20:19Z No. of bitstreams: 1 Structural Characterization of the Internal Transcribed Spacer 2.pdf: 925048 bytes, checksum: bb816251eece2b89d05cb5592d21e67c (MD5)Approved for entry into archive by Luciane Willcox ([email protected]) on 2016-09-30T18:28:14Z (GMT) No. of bitstreams: 1 Structural Characterization of the Internal Transcribed Spacer 2.pdf: 925048 bytes, checksum: bb816251eece2b89d05cb5592d21e67c (MD5)Made available in DSpace on 2016-09-30T18:28:14Z (GMT). No. of bitstreams: 1 Structural Characterization of the Internal Transcribed Spacer 2.pdf: 925048 bytes, checksum: bb816251eece2b89d05cb5592d21e67c (MD5) Previous issue date: 2013-02-19FAPESP, Grant 06/61217-3Campinas State University. Center for Molecular Biology and Genetic Engineering. Laboratory of Animal Genetics and Evolution. Campinas, SP, Brazil.Universidade Estadual de Campinas. Centro de Biologia Molecular e Engenharia Genética. Laboratório de Genética e Evolução Animal. Campinas, SP, Brasil / Universidade Estadual de Campinas. Instituto de Biologia. Departamento de Genética e Evolução Animal. Campinas, SP, Brasil.Fundação Oswaldo Cruz. Instituto Carlos Chagas. Curitiba, PR, Brasil.The internal transcribed spacer 2 (ITS2) of the eukaryotic ribosomal DNA (rDNA) cluster plays an essential role in processing of the ribosomal RNA, which is primarily accomplished by the secondary structures acquired by the molecule after transcription. Two possible structural conformation models have been proposed for the ITS2 region, the "ring model" and the "hairpin model," and the former has been widely used in many molecular phylogenetic analyses incorporating structural information available to date. To evaluate the validity of this model, in vitro transcribed ITS2 molecules from species representing the three superfamilies of the Calyptratae clade (Diptera: Schizophora), namely Cochliomyia hominivorax, Musca domestica, and Glossina morsitans, were submitted to enzymatic digestion with single- and double-stranded specific nucleases (RNases I, A, T1, and V1). The resulting fragments were analyzed by capillary electrophoresis and digestion sites were mapped in the secondary structure models which were obtained by in silico prediction with further refinement by homology comparisons. The pattern of RNA fragments generated by these RNases show a high degree of correlation to most of the predicted helix-loop regions and structural motifs. Discrepancies to the models can be explained by alternative structural conformation dynamics (in M. domestica and G. morsitans) and by higher-order factors (such as tertiary interactions) that may stabilize thermodynamically unfavored structures (in C. hominivorax)

A Method for Purifying Native Transthyretin from Human Plasma

Submitted by Luciane Willcox ([email protected]) on 2016-08-25T15:01:25Z No. of bitstreams: 1 a-method-for-purifying-native-transthyretin-from-human-plasma-2167-0501-1000187.pdf: 828721 bytes, checksum: 9815e84d8538dc972d3fe82580b5fa2f (MD5)Approved for entry into archive by Luciane Willcox ([email protected]) on 2016-08-26T12:46:28Z (GMT) No. of bitstreams: 1 a-method-for-purifying-native-transthyretin-from-human-plasma-2167-0501-1000187.pdf: 828721 bytes, checksum: 9815e84d8538dc972d3fe82580b5fa2f (MD5)Made available in DSpace on 2016-08-26T12:46:28Z (GMT). No. of bitstreams: 1 a-method-for-purifying-native-transthyretin-from-human-plasma-2167-0501-1000187.pdf: 828721 bytes, checksum: 9815e84d8538dc972d3fe82580b5fa2f (MD5) Previous issue date: 2015-09-21Oswaldo Cruz Fundation. Institute Carlos Chagas. Laboratory of Proteomics and Proteins Engineering. Curitiba, PR, Brazil / Universidade Federal do Paraná. Curitiba, PR, Brazil.Oswaldo Cruz Fundation. Institute Carlos Chagas. Laboratory of Proteomics and Proteins Engineering. Curitiba, PR, Brazil.Oswaldo Cruz Fundation. Institute Carlos Chagas. Laboratory of Proteomics and Proteins Engineering. Curitiba, PR, Brazil.Oswaldo Cruz Fundation. Institute Carlos Chagas. Laboratory of Proteomics and Proteins Engineering. Curitiba, PR, Brazil.Transthyretin is a homotetrameric thyroid-hormone-transporting protein that binds to the retinol binding protein thus being involved in metabolism, growth, fertility, homeostasis of the cardiovascular and central nervous system, cell differentiation, reproduction, development and maintenance the cognitive processes during aging. Currently, there are several methodologies for natively purifying TTR from plasma, serum, tears, and amyloid fibrils; however, these procedures are laborious. Herein, a low-cost and simple protocol to purify TTR from human plasma is described. It involves the separation of plasma proteins by size exclusion and DEAE chromatography. The homogeneity was assessed by SDS-PAGE and by tandem mass spectrometry using an Orbitrap-XL (Thermo, San Jose-CA)

Identification and characterization of an alternatively spliced isoform of the human protein phosphatase 2Aα catalytic subunit

Submitted by Manoel Barata ([email protected]) on 2018-09-14T12:28:06Z No. of bitstreams: 1 JournalBiolChemistryzb4853.pdf: 1990964 bytes, checksum: bb68ee6b122af42a80fca5054d5c4a3d (MD5)Approved for entry into archive by Manoel Barata ([email protected]) on 2018-09-14T19:47:44Z (GMT) No. of bitstreams: 1 JournalBiolChemistryzb4853.pdf: 1990964 bytes, checksum: bb68ee6b122af42a80fca5054d5c4a3d (MD5)Made available in DSpace on 2018-09-14T19:47:44Z (GMT). No. of bitstreams: 1 JournalBiolChemistryzb4853.pdf: 1990964 bytes, checksum: bb68ee6b122af42a80fca5054d5c4a3d (MD5) Previous issue date: 2012Centro Nacional de Pesquisa em Energia e Materiais. Laboratório Nacional de Biociências. Campinas, SP, Brasil. / Universidade Estadual de Campinas. Instituto de Biologia. Campinas, SP, Brasil.Centro Nacional de Pesquisa em Energia e Materiais. Laboratório Nacional de Biociências. Campinas, SP, Brasil.Universidade Estadual de Campinas. Centro de Biologia Molecular e Engenharia Genética, Campinas, SP, Brasil.Centro Nacional de Pesquisa em Energia e Materiais. Laboratório Nacional de Biociências. Campinas, SP, Brasil. / Universidade Estadual de Campinas. Instituto de Biologia. Campinas, SP, Brasil.Universidade Estadual de Campinas. Centro de Biologia Molecular e Engenharia Genética, Campinas, SP, Brasil. / Fundação Oswaldo Cruz. Instituto Carlos Chagas. Curitiba, PR, Brasil.PP2A is the main serine/threonine-specific phosphatase in animal cells. The active phosphatase has been described as a holoenzyme consisting of a catalytic, a scaffolding, and a variable regulatory subunit, all encoded by multiple genes, allowing for the assembly of more than 70 different holoenzymes. The catalytic subunit can also interact with α4, TIPRL (TIP41, TOR signaling pathway regulator-like), the methyl-transferase LCMT-1, and the methyl-esterase PME-1. Here, we report that the gene encoding the catalytic subunit PP2Acα can generate two mRNA types, the standard mRNA and a shorter isoform, lacking exon 5, which we termed PP2Acα2. Higher levels of the PP2Acα2 mRNA, equivalent to the level of the longer PP2Acα mRNA, were detected in peripheral blood mononuclear cells that were left to rest for 24 h. After this time, the peripheral blood mononuclear cells are still viable and the PP2Acα2 mRNA decreases soon after they are transferred to culture medium, showing that generation of the shorter isoform depends on the incubation conditions. FLAG-tagged PP2Acα2 expressed in HEK293 is catalytically inactive. It displays a specific interaction profile with enhanced binding to the α4 regulatory subunit, but no binding to the scaffolding subunit and PME-1. Consistently, α4 out-competes PME-1 and LCMT-1 for binding to both PP2Acα isoforms in pulldown assays. Together with molecular modeling studies, this suggests that all three regulators share a common binding surface on the catalytic subunit. Our findings add important new insights into the complex mechanisms of PP2A regulation