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2.
Gac. méd. Méx ; 156(4): 324-329, Jul.-Aug. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1249919

RESUMO

Abstract In the efforts to explain COVID-19 pathophysiology, studies are being carried out on the correspondence between the expression of SARS-CoV-2 cell receptors and viral sequences. ACE2, CD147 and TMPRSS2 receptors expression could indicate poorly explored potential infection targets. For the genomic analysis of SARS-CoV-2 receptors, using BioGPS information was decided, which is a portal that centralizes genetic annotation resources, in combination with that of The Human Protein Atlas, the largest portal of human transcriptome and proteome data. We also reviewed the most recent articles on the subject. RNA and viral receptor proteins expression was observed in numerous anatomical sites, which partially coincides with the information reported in the literature. High expression in testicular cells markedly stood out, and it would be therefore important ruling out whether this anatomical site is a SARS-CoV-2 reservoir; otherwise, germ cell damage, as it is observed in infections with other RNA viruses, should be determined.


Resumen En el afán por explicar la fisiopatogenia de COVID-19 se están realizando estudios en torno a la correspondencia entre la expresión de receptores celulares de SARS-CoV-2 y las secuencias virales. La expresión de los receptores ACE2, CD147 y TMPRSS2 podría indicar blancos de infección poco explorados. Para el análisis genómico de los receptores de SARS-CoV-2 se optó por utilizar la información del BioGPS, un portal que centraliza los recursos de anotación genética, en combinación con la de The Human Protein Atlas, el portal más grande de datos del transcriptoma y proteoma humanos. También se revisaron los artículos más recientemente respecto al tema. En numerosos sitios anatómicos se observó la expresión de ARN y proteínas de los receptores del virus, que coinciden parcialmente con la información reportada en la literatura. Resaltó la alta expresión en las células de los testículos, por lo que sería importante descartar si este sitio anatómico es un reservorio de SARS-CoV-2; de no ser así, determinar el daño en las células germinales, tal como sucede en infecciones por otros virus ARN.


Assuntos
Humanos , Pneumonia Viral/virologia , Testículo/virologia , Infecções por Coronavirus/virologia , Betacoronavirus/isolamento & purificação , Pneumonia Viral/fisiopatologia , Serina Endopeptidases/genética , Regulação da Expressão Gênica , Latência Viral , Infecções por Coronavirus/fisiopatologia , Peptidil Dipeptidase A/genética , Basigina/genética , Pandemias , Enzima de Conversão de Angiotensina 2 , SARS-CoV-2 , COVID-19
3.
Gac. méd. Méx ; 156(4): 348-351, Jul.-Aug. 2020. graf
Artigo em Inglês | LILACS | ID: biblio-1249923

RESUMO

Abstract Introduction: Reports of dermatological manifestations in patients with COVID-19 suggest a possible cutaneous tropism of SARS-CoV-2; however, the capacity of this virus to infect the skin is unknown. Objective: To determine the susceptibility of the skin to SARS-CoV-2 infection based on the expression of viral entry factors ACE2 and TMPRSS2 in this organ. Method: A comprehensive analysis of human tissue gene expression databases was carried out looking for the presence of the ACE2 and TMPRSS2 genes in the skin. mRNA expression of these genes in skin-derived human cell lines was also assessed. Results: The analyses showed high co-expression of ACE2 and TMPRSS2 in the gastrointestinal tract and kidney, but not in the skin. Only the human immortalized keratinocyte HaCaT cell line expressed detectable levels of ACE2, and no cell line originating in the skin expressed TMPRSS2. Conclusions: Our results suggest that cutaneous manifestations in patients with COVID-19 cannot be directly attributed to the virus. It is possible that cutaneous blood vessels endothelial damage, as well as the effect of circulating inflammatory mediators produced in response to the virus, are the cause of skin involvement.


Resumen Introducción: Reportes de manifestaciones dermatológicas en pacientes con COVID-19 sugieren un posible tropismo cutáneo del virus SARS-CoV-2; sin embargo, se desconoce la capacidad de este virus para infectar la piel. Objetivo: Determinar la susceptibilidad de la piel a la infección por SARS-CoV-2 con base en la expresión de los factores de entrada viral ACE2 y TMPRSS2 en dicho órgano. Método: Se buscaron los genes ACE2 y TMPRSS2 en la piel, para lo cual se realizó un análisis extenso de las bases de datos de expresión genética en tejidos humanos. Asimismo, se evaluó la expresión de dichos genes en líneas celulares humanas derivadas de la piel. Resultados: Los análisis mostraron alta expresión conjunta de ACE2 y TMPRSS2 en el tracto gastrointestinal y en los riñones, pero no en la piel. Solo la línea celular de queratinocitos humanos inmortalizados HaCaT expresó niveles detectables de ACE2 y ninguna línea celular de origen cutáneo expresó TMPRSS2. Conclusiones: Los resultados sugieren que las manifestaciones dermatológicas en pacientes con COVID-19 no pueden ser atribuidas directamente al virus; es posible que sean originadas por el daño endotelial a los vasos sanguíneos cutáneos y el efecto de los mediadores inflamatorios circulantes producidos en respuesta al virus.


Assuntos
Humanos , Pneumonia Viral/complicações , Serina Endopeptidases/genética , Dermatopatias Virais/virologia , Infecções por Coronavirus/complicações , Peptidil Dipeptidase A/genética , Pneumonia Viral/genética , Pele/virologia , Linhagem Celular , Regulação da Expressão Gênica , Infecções por Coronavirus/genética , Predisposição Genética para Doença , Internalização do Vírus , Tropismo Viral/fisiologia , Pandemias , Betacoronavirus/isolamento & purificação , Enzima de Conversão de Angiotensina 2 , SARS-CoV-2 , COVID-19
4.
Braz. j. biol ; 78(2): 281-288, May-Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-888879

RESUMO

Abstract Knowledge of specific enzyme activity, along with animal habits and digestive capacity is essential in formulating an appropriate diet for any species. In this study, we evaluated and characterized the activity of digestive enzymes present in the liver, intestine, and stomach of Paralichthys orbignyanus. The effects of pH and temperature on enzyme activity were also evaluated via the use of specific substrates. The use of specific substrates and inhibitors showed strong evidence of the presence of trypsin (BApNA= 0.51 ± 0.2 mU mg-1), chimotrypsin (SApNA= 2.62 ± 1.8 mU mg-1), and aminopeptidases (Leu-p-Nan =0.9709 ± 0.83 mU mg-1) in the intestine. Optimum pH for the activity of trypsin, chemotrypsin, leucino aminopeptidase, amilase, and pepsin were 9.5, 9.0, 8.0, 7.5, and 3.5, respectively, while optimum temperatures were 50, 50, 50, 40, and 45 °C, respectively. These results provide additional information regarding the biology of Brazilian flounder and can be used as a basis for further studies regarding fish feeding physiology.


Resumo O conhecimento da atividade enzimática é essencial para formular uma correta dieta específica para espécie, além de estarem correlacionadas com o hábito da alimentação e capacidade digestive. Neste estudo determinamos e caracterizamos a atividade enzimática presente no intestino, estômago e fígado do linguado Paralichthys orbignyanus. Os efeitos da temperatura e pH sobre a atividade enzimática também foram avaliados utilizando substratos específicos. O uso de substratos e inibidores específicos mostrou uma forte evidência da presença da tripsina (BApNA = 0,51 ± 0,2 mU mg-1), quimotripsina (SAPNA = 2,62 ± 1,8 mU mg-1), e as aminopeptidases (Leu-p-Nan = 0,97 ± 0,83 mU mg-1) no intestino. O pH ótimo observado para a atividade de tripsina, quimotripsina, leucino aminopeptidase, amilase e pepsina foi 9,5, 9,0, 8,0, 7,5 e 3,5, respectivamente. A temperatura ótima observada foi 50, 50, 50, 40 e 45 °C, respectivamente. Estes resultados fornecem informações adicionais sobre a biologia do linguado brasileiro e pode ser usado como base para novos estudos sobre fisiologia alimentar.


Assuntos
Animais , Linguado/fisiologia , Proteínas de Peixes/metabolismo , Proteínas de Peixes/química , Trato Gastrointestinal/enzimologia , Aminopeptidases/metabolismo , Aminopeptidases/química , Temperatura , Estabilidade Enzimática , Brasil , Serina Endopeptidases/metabolismo , Serina Endopeptidases/química , Concentração de Íons de Hidrogênio , Fígado/enzimologia
5.
Electron. j. biotechnol ; 32: 63-68, Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1022642

RESUMO

Background: Although immunosuppressive therapies have made organ transplantation a common medical procedure worldwide, chronic toxicity has a major issue for long-term treatment. One method to improve therapies and methods is the application of immunomodulatory agents from parasites such as Hypoderma lineatum. Hypodermin A (HA) is a serine esterase secreted by the larvae of Hypoderma lineatum, several studies demonstrated its immunosuppressive mechanism in vitro, and recently we discovered that HA inhibits the expression of interferon (IFN)-γ and interleukin (IL)-2 and activates IL-10 expression. Therefore, we hypothesized that it might be a potential agent used to block allograft rejections. However, most studies of the immunosuppressive mechanisms associated with HA were undertaken at the cellular level. In order to augment these studies, we evaluated the immunosuppressive effects of HA in vivo using an HA transgenic mouse model. Result: Our results revealed similar findings to those reported by in vitro studies, specifically that HA induced prostaglandin E2 expression, downregulated IFN-γ and IL-2 expression, and promoted IL-10 secretion via E-type prostanoid receptor 4. Additionally, we observed that HA overexpression inhibited lipopolysaccharide-induced TLR4 activation. These findings provide insight into a new potential agent capable of blocking graft rejection. Conclusion: Our founding suggested that HA-related treatment could be a promising option to improve the viability of grafts in human.


Assuntos
Animais , Camundongos , Serina Endopeptidases/imunologia , Dípteros/enzimologia , Dípteros/imunologia , Rejeição de Enxerto/imunologia , Ensaio de Imunoadsorção Enzimática , Serina Endopeptidases/metabolismo , Western Blotting , Citocinas , Terapia de Imunossupressão , Interleucinas/antagonistas & inibidores , Interferons/antagonistas & inibidores , Interleucina-10/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 4 Toll-Like , Reação em Cadeia da Polimerase em Tempo Real , Rejeição de Enxerto/enzimologia , Rejeição de Enxerto/prevenção & controle
6.
Biomédica (Bogotá) ; 37(supl.2): 135-142, jul.-set. 2017. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-888532

RESUMO

Resumen Introducción. Aedes aegypti y Ae. albopictus son reconocidos vectores de arbovirus como los del dengue, la fiebre amarilla, el chikungunya y el Zika, en regiones tropicales y subtropicales del mundo. En Colombia, la distribución geográfica de Ae. albopictus ha sufrido un incremento y hoy incluye ciudades como Cali y Medellín. Hasta ahora, sin embargo, no se ha recabado información concluyente sobre su infección viral y su capacidad de transmisión a los humanos. Objetivo. Determinar la infección natural por dengue en ejemplares de Ae. albopictus recolectados en un área urbana de Medellín. Materiales y métodos. Se recolectaron individuos de Ae. albopictus en el campus de la Universidad Nacional de Colombia, sede Medellín. Se confirmó su clasificación taxonómica mediante el análisis del gen citocromo oxidasa I (COI), y se extrajo el ARN total para la identificación del virus del dengue y de los respectivos serotipos. La presencia del genotipo DENV se infirió mediante el análisis del gen NS3. Resultados. El análisis del COI corroboró el estatus taxonómico de Ae. albopictus. Uno de los mosquitos procesados fue positivo para DENV-2 y el análisis del NS3 mostró una gran similitud con el genotipo asiático-americano. Conclusión. Se reporta la infección con DENV-2 en Ae. albopictus en Medellín, Colombia. La presencia del genotipo asiático-americano en una zona urbana sugiere su posible circulación entre humanos y en Ae. albopictus, lo cual alerta sobre su eventual papel en la transmisión del DENV-2, y sobre la necesidad de incluir esta especie en la vigilancia entomológica en Colombia.


Abstract Introduction: Aedes aegypti and Ae. albopictus are recognized vectors of dengue, yellow fever, chikungunya and Zika arboviruses in several countries worldwide. In Colombia, Ae. albopictus geographical distribution has increased to include highly populated cities such as Cali and Medellín. Although this species has been frequently found in urban and semi-urban zones in the country, its role as vector of the dengue fever is poorly known. Objective: To identify the presence of Ae. albopictus specimens naturally infected with dengue virus collected in Medellín. Materials and methods: Insects were collected in the Universidad Nacional de Colombia campus in Medellín. Individuals were classified as Ae. albopictus and confirmed by DNA barcode region analysis. Mosquitoes were processed for dengue virus identification, and a fragment of the NS3 gen was sequenced and compared with DENV-2 genotypes reported in the literature. Results: Sequence analysis of COI indicated Ae. albopictus individuals were similar to those recently reported in Colombia, and genetically close to those from other regions worldwide. Among the pools tested one was positive for DENV-2, and the NS3 analysis indicated it belonged to the Asian-American clade. Conclusion: We report the presence Ae. albopictus naturally infected with the Asian-American genotype of DENV-2 in Colombia. The presence of Ae. albopictus specimens carrying the most common genotype infecting humans in a highly populated city such as Medellín indicates its potential role as dengue vector in Colombia and highlights the relevance of including it in current vector surveillance strategies.


Assuntos
Animais , Humanos , Aedes/virologia , Dengue/epidemiologia , Vírus da Dengue/isolamento & purificação , Mosquitos Vetores/virologia , Serina Endopeptidases/genética , Sorotipagem , Reação em Cadeia da Polimerase , Cidades , Proteínas não Estruturais Virais/genética , Colômbia/epidemiologia , DNA Complementar/análise , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Insetos/genética , Aedes/genética , RNA Helicases/genética , Dengue/transmissão , Vírus da Dengue/classificação , Vírus da Dengue/genética , Genótipo
7.
Electron. j. biotechnol ; 29: 7-12, sept. 2017. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-1016095

RESUMO

Background: DegP is a serine protease that specifically cleaves and refolds unfolding proteins in the periplasmic space of the cells. To date, there is no information regarding DegP from halophilic bacteria. Chromohalobacter salexigens BKL5 is a moderately halophilic bacterium that has the ability to grow in a media containing more than 15% salt. Therefore, the objectives of this work were to clone and overexpress DegP-encoding gene from C. salexigens BKL5 and characterize its biochemical properties. Results: DegP-encoding gene was overexpressed in Escherichia coli BL21(DE3) CodonPlus in an active form. SDS-PAGE analysis showed that the molecular weight of the recombinant DegP was 45 kDa. Size-exclusion chromatography analysis suggested that recombinant DegP was present in two multimeric states, hexameric and dodecameric, with molecular weights of 297.9 and 579.12 kDa, respectively. Both conformations were enzymatically active when casein was used as substrate for enzymatic assay. Circular dichroism analysis showed that recombinant DegP was composed of 0.21­0.29 helical content, which was comparable to the helical content in the crystal structure of E. coli DegP. The basic/acidic residue ratio of recombinant DegP was 0.56, which was slightly higher than that of DegP from extreme halophiles (average, 0.45) but significantly lower than that of DegP from nonhalophiles (average, 0.94). Conclusions: Recombinant DegP from C. salexigens BKL5 showed proteolytic activity when ß-casein was used as a substrate. In silico analysis indicated that recombinant DegP had characteristics similar to those of halophilic proteins depending on its amino acid composition.


Assuntos
Serina Endopeptidases/genética , Proteínas Periplásmicas/genética , Chromohalobacter/enzimologia , Proteólise , Proteínas de Choque Térmico/genética , Proteínas Recombinantes , Serina Endopeptidases/metabolismo , Caseínas , Cromatografia em Gel , Dicroísmo Circular , Clonagem Molecular , Proteínas Periplásmicas/metabolismo , Eletroforese em Gel de Poliacrilamida , Escherichia coli , Salinidade , Chromohalobacter/genética , Proteínas de Choque Térmico/metabolismo , Peso Molecular
8.
Biomédica (Bogotá) ; 37(supl.1): 121-132, abr. 2017. graf
Artigo em Espanhol | LILACS | ID: biblio-888518

RESUMO

Resumen Introducción. El virus del Zika (ZIKV) es un flavivirus con envoltura, transmitido a los seres humanos principalmente por el vector Aedes aegypti. La infección por ZIKV se ha asociado con un gran neurotropismo y con efectos neuropáticos, como el síndrome de Guillain-Barré en el adulto y la microcefalia fetal y posnatal, así como con un síndrome de infección congénita similar al producido por el virus de la rubéola (RV). Objetivo. Comparar las estructuras moleculares de la proteína de envoltura E del virus del Zika (E-ZIKV) y de la E1 del virus de la rubéola (E1-RV), y plantear posibles implicaciones en el neurotropismo y en las alteraciones del sistema nervioso asociadas con el ZIKV. Materiales y métodos. La secuencia de aminoácidos de la proteína E-ZIKV (PDB: 5iZ7) se alineó con la de la glucopreteína E1 del virus de la rubéola (PDB: 4ADG). Los elementos de la estructura secundaria se determinaron usando los programas Vector NTI Advance®, DSSP y POSA, así como herramientas de gestión de datos (AlignX®). Uno de los criterios principales de comparación y alineación fue la asignación de residuos estructuralmente equivalentes, con más de 70 % de identidad. Resultados. La organización estructural de la proteína E-ZIKV (PDB: 5iZ7) fue similar a la de E1-RV (PDB: 4ADG) (70 a 80 % de identidad), y se observó una correspondencia con la estructura definida para las glucoproteínas de fusión de membrana de clase II de los virus con envoltura. E-ZIKV y E1-RV exhibieron elementos estructurales de fusión muy conservados en la región distal del dominio II, asociados con la unión a los receptores celulares de entrada del virus de la rubéola (glucoproteína de mielina del oligodendrocito, Myelin Oligodendrocyte Glycoprotein, MOG), y con los receptores celulares Axl del ZIKV y de otros flavivirus. Conclusión. La comparación de las proteínas E-ZIKV y E1-RV es un paso necesario hacia la definición de otros factores moleculares determinantes del neurotropismo y la patogenia del ZIKV, el cual puede contribuir a generar estrategias de diagnóstico, prevención y tratamiento de las complicaciones neurológicas inducidas por el ZIKV.


Abstract Introduction: Zika virus (ZIKV) is an enveloped flavivirus transmitted to humans mainly by Aedes aegypti. ZIKV infection has been associated with high neurotropism and neuropathic effects such as the Guillain-Barré syndrome in adults, and fetal and postnatal microcephaly and the congenital Zika virus syndrome similar to that produced by rubella virus (VR). Objective: To compare Zika virus membrane protein E (E-ZIKV) and rubella virus membrane protein E1 (E1-RV), and to propose possible implications for neurotropism and nervous system disorders associated with ZIKV infections. Materials and methods: The amino acid sequence of E-ZIKV protein (PDB: 5iZ7) was aligned to that of rubella virus glycoprotein E1 (PDB: 4ADG). The secondary structure elements were determined using the programs Vector NTI Advance®, DSSP, and POSA, and integrated data management tools (AlignX®). One of the main comparison and alignment criteria was the allocation of structurally equivalent residues with more than 70% identity. Results: E-ZIKV structural organization (PDB: 5iZ7) was similar to that of E1-RV (PDB: 4ADG) (70%-80% identity), and it was consistent with relevant structural features of viral membrane class II fusion glycoproteins. E-ZIKV and E1-RV exhibited highly conserved fusion structural elements at the distal region of domain II, which has been associated with the RV myelin oligodendrocyte glycoprotein and Axl cell receptors in ZIKV and other flaviviruses. Conclusion: The comparison of E-ZIKV and E1-RV proteins constitutes an essential step towards the definition of ZIKV neurotropism and pathogenesis molecular determinants, and for the adoption of diagnosis, prevention and treatment strategies against neurological complications induced by ZIKV infection.


Assuntos
Humanos , Proteínas Virais/química , Serina Endopeptidases/metabolismo , Serina Endopeptidases/química , Proteínas do Envelope Viral/metabolismo , Zika virus/química , Vírus do Sarampo/química , Proteínas Virais/fisiologia , Proteínas Virais/genética , Zika virus/fisiologia , Zika virus/patogenicidade , Vírus do Sarampo/fisiologia , Vírus do Sarampo/patogenicidade , Biologia Molecular
9.
Ann. hepatol ; 16(1): 77-85, Jan.-Feb. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-838089

RESUMO

Abstract: Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. We have previously shown that hepatic reticuloendothelial system (RES) iron deposition is associated with an advanced degree of nonalcoholic steatohepatitis (NASH) in humans. In this study, we aimed to determine differentially expressed genes related to iron overload, inflammation and oxidative stress pathways, with the goal of identifying factors associated with NASH progression. Seventy five patients with NAFLD were evaluated for their biochemical parameters and their liver tissue analyzed for NASH histological characteristics. Gene expression analysis of pathways related to iron homeostasis, inflammation and oxidative stress was performed using real-time PCR. Gene expression was compared between subjects based on disease status and presence of hepatic iron staining. We observed increased gene expression of hepcidin (HAMP) (2.3 fold, p = 0.027), transmembrane serine proteinase 6 (TMPRSS6) (8.4 fold, p = 0.003), signal transducer and activator of transcription 3 (STAT3) (5.5 fold, p = 0.004), proinflammatory cytokines; IL-1β (2.7 fold, p = 0.046) and TNF-α (3.8 fold, p = 0.001) in patients with NASH. TMPRSS6, a negative regulator of HAMP, is overexpressed in patients with NASH and HIF1α (hypoxia inducible factor-1) is downregulated. NAFLD patients with hepatic iron deposition exhibited higher hepcidin expression (3.1 fold, p = 0.04) but lower expression of cytokines. In conclusion, we observed elevated hepatic HAMP expression in patients with NASH and in NAFLD patients who had hepatic iron deposition, while proinflammatory cytokines displayed elevated expression only in patients with NASH, suggesting a regulatory role for hepcidin in NAFL to NASH transition and in mitigating inflammatory responses.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estresse Oxidativo/genética , Sobrecarga de Ferro/genética , Hepatopatia Gordurosa não Alcoólica/genética , Inflamação/genética , Ferro/análise , Fígado/química , Serina Endopeptidases/genética , Regulação da Expressão Gênica , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/sangue , Mediadores da Inflamação/sangue , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/sangue , Fator de Transcrição STAT3/genética , Interleucina-1beta/genética , Interleucina-1beta/sangue , Reação em Cadeia da Polimerase em Tempo Real , Hepcidinas/genética , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/sangue , Inflamação/diagnóstico , Inflamação/sangue , Fígado/patologia , Proteínas de Membrana/genética
10.
Biomédica (Bogotá) ; 37(1): 131-140, ene.-feb. 2017. graf
Artigo em Espanhol | LILACS | ID: biblio-888451

RESUMO

Resumen Introducción: El dengue es una enfermedad causada por uno de los cuatro serotipos del virus del dengue (DENV) y es endémica en, aproximadamente, 130 países. Su incidencia ha aumentado notablemente en las últimas décadas, así como la frecuencia y la magnitud de los brotes. A pesar de los esfuerzos, no existen tratamientos profilácticos ni terapéuticos contra la enfermedad y, en ese contexto, el estudio de los procesos que gobiernan el ciclo de infección del DENV es esencial para desarrollar vacunas o terapias antivirales. Una de las moléculas del DENV más prometedoras es la proteína no estructural 3 (NS3), la cual es indispensable para la replicación viral y es uno de los principales blancos inmunológicos durante la infección. Objetivo: Producir anticuerpos policlonales para contribuir a los futuros estudios sobre las interacciones entre la proteína NS3 y otras proteínas celulares. Materiales y métodos: Se expresaron dos proteínas recombinantes del dominio helicasa de NS3 del DENV de serotipo 2, las cuales se emplearon para inmunizar ratas y producir anticuerpos policlonales. Resultados: Los anticuerpos producidos fueron útiles en ensayos de Western blot e inmunofluorescencia y se reportó por primera vez un anticuerpo policlonal anti-NS3 que permitió la inmunoprecipitación de la proteína viral y la detecta con Western blot sin necesidad de inducir sobreexpresión de NS3 o de usar extractos de células marcados metabólicamente con radioisótopos. Conclusión: Las proteínas recombinantes expresadas y los anticuerpos producidos constituyen herramientas valiosas para estudiar procesos infecciosos del DENV que involucren a la proteína NS3 y evaluar pruebas dirigidas a interferir las funciones de esta proteína.


Abstract Introduction: Dengue is a disease caused by one of four serotypes of the dengue virus (DENV) and is endemic in approximately 130 countries. The incidence of dengue has increased dramatically in recent decades, as well as the frequency and magnitude of outbreaks. Despite all efforts, there are no prophylactic or therapeutic treatments for the disease. Accordingly, research on the processes governing the DENV infection cycle is essential to develop vaccines or antiviral therapies. One of the most attractive DENV molecules to investigate is nonstructural protein 3 (NS3), which is essential for viral replication and a major immune target for infection. Objective: To produce antibodies to support future studies on NS3 and its cellular interactions with other proteins. Materials and methods: Two recombinant proteins of the helicase domain of DENV NS3 serotype 2 were expressed, and used to immunize mice and produce polyclonal antibodies. Results: The antibodies produced were useful in Western blot and immunofluorescence tests. We report an NS3 antibody that immunoprecipitates the viral protein and detects it in Western blot with no need to over-express it or use cell extracts with metabolic radiolabeling.


Assuntos
Animais , Humanos , Camundongos , Replicação Viral/fisiologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Dengue/virologia , Vírus da Dengue/imunologia , Anticorpos Antivirais/imunologia , Replicação Viral/genética , Replicação Viral/imunologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Serina Endopeptidases/química , Western Blotting , Proteínas não Estruturais Virais/química , RNA Helicases/genética , RNA Helicases/metabolismo , RNA Helicases/química , Anticorpos Antivirais/metabolismo , Anticorpos Antivirais/química
11.
Acta cir. bras ; 31(5): 314-319, May 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-783800

RESUMO

ABSTRACT PURPOSE : To evaluate the effects of platelet rich plasma (PRP) on the healing of fascia wherein peritonitis has been created. METHODS: Twenty eight Wistar Albino rats were divided into four groups. Only a primary fascial repair following laparotomy was performed on Group 1, a primary fascial repair performed and PRP treatment applied following laparotomy on Group 2, and a fecal peritonitis created following laparotomy and a primary fascial repair carried out on Group 3. A fecal peritonitis was created following laparotomy and primary fascial repair and PRP treatment on the fascia was carried out on Group 4. RESULTS: TNF-α was found to be significantly lower in the control group (Group 1). It was detected at the highest level in the group in which fecal peritonitis was created and PRP applied (Group 4). TGF-β was determined as being significantly higher only in Group 4. Histopathologically, the differences between the groups in terms of cell infiltration and collagen deposition were not found to be significant. CONCLUSION: When platelet rich plasma was given histologically and biochemicaly as wound healing parameters cellular infiltration, collagen accumulation, and tissue hydroxyiproline levels were not increased but neovascularization, fibroblast activation and TNF Alfa levels were increased and PRP accelerated wound healing.


Assuntos
Animais , Peritonite/complicações , Cicatrização , Plasma Rico em Plaquetas , Fáscia/fisiologia , Peritonite/metabolismo , Serina Endopeptidases/metabolismo , Distribuição Aleatória , Fator de Crescimento Transformador beta/análise , Fator de Crescimento Transformador beta/metabolismo , Colágeno/efeitos dos fármacos , Colágeno/metabolismo , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/metabolismo , Ratos Wistar , Gelatinases/metabolismo , Neovascularização Fisiológica , Modelos Animais , Fáscia/irrigação sanguínea , Hidroxiprolina/análise , Hidroxiprolina/metabolismo , Proteínas de Membrana/metabolismo
12.
Biol. Res ; 49: 1-10, 2016. ilus, graf
Artigo em Inglês | LILACS | ID: biblio-950843

RESUMO

Schizophrenia is a severe psychiatric disorder that results in a significant disability for the patient. The disorder is characterized by impairment of the adaptive orchestration of actions, a cognitive function that is mainly dependent on the prefrontal cortex. This behavioral deficit, together with cellular and neurophysiological alterations in the prefrontal cortex, as well as reduced density of GABAergic cells and aberrant oscillatory activity, all indicate structural and functional deficits of the prefrontal cortex in schizophrenia. Among the several risk factors for the development of schizophrenia, stress during the prenatal period has been identified as crucial. Thus, it is proposed that prenatal stress induces neurodevelopmental alterations in the prefrontal cortex that are expressed as cognitive impairment observed in schizophrenia. However, the precise mechanisms that link prenatal stress with the impairment of prefrontal cortex function is largely unknown. Reelin is an extracellular matrix protein involved in the development of cortical neural connectivity at embryonic stages, and in synaptic plasticity at postnatal stages. Interestingly, down-regulation of reelin expression has been associated with epigenetic changes in the reelin gene of the prefrontal cortex of schizophrenic patients. We recently showed that, similar to schizophrenic patients, prenatal stress induces down-expression of reelin associated with the methylation of its promoter in the rodent prefrontal cortex. These alterations were paralleled with altered prefrontal cortex functional connectivity and impairment in prefrontal cortex-dependent behavioral tasks. Therefore, considering molecular, cellular, physiological and behavioral evidence, we propose a unifying framework that links prenatal stress and prefrontal malfunction through epigenetic alterations of the reelin gene.


Assuntos
Humanos , Feminino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Esquizofrenia/etiologia , Esquizofrenia/fisiopatologia , Estresse Fisiológico/fisiologia , Encéfalo/embriologia , Serina Endopeptidases/genética , Moléculas de Adesão Celular Neuronais/genética , Proteínas da Matriz Extracelular/genética , Epigênese Genética/fisiologia , Proteínas do Tecido Nervoso/genética , Transtornos do Comportamento Social/fisiopatologia , Encéfalo/fisiopatologia , Expressão Gênica , Fatores de Risco , Transtornos Cognitivos/fisiopatologia , Metilação de DNA
13.
Braz. j. microbiol ; 46(3): 879-883, July-Sept. 2015. tab
Artigo em Inglês | LILACS | ID: lil-755800

RESUMO

Studies investigating rickettsial infections in ticks parasitizing wild animals in the Northeast region of Brazil have been confined to the detection of Rickettsia amblyommii in immature stages of Amblyomma longirostre collected from birds in the state of Bahia, and in immatures and females of Amblyomma auriculariumcollected from the striped hog-nosed skunk (Conepatus semistriatus) and armadillos (Euphractus sexcinctus) in the state of Pernambuco. The current study extends the distribution of R. amblyommii (strain Aranha), which was detected in A. longirostre collected from the thin-spined porcupine Chaetomys subspinosus and the hairy dwarf porcupine Coendou insidiosus. In addition, we report the first detection of Rickettsia bellii in adults of A. longirostre collected from C. insidiosus in the state of Bahia.

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Assuntos
Animais , Ixodidae/microbiologia , Infecções por Rickettsia/microbiologia , Rickettsia/genética , Rickettsia/isolamento & purificação , Infestações por Carrapato/microbiologia , Animais Selvagens , Tatus , Sequência de Bases , Aves , Brasil , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Citrato (si)-Sintase/genética , DNA Bacteriano , Proteínas de Choque Térmico/genética , Mephitidae , Dados de Sequência Molecular , Tipagem Molecular , Porcos-Espinhos , Proteínas Periplásmicas/genética , Análise de Sequência de DNA , Serina Endopeptidases/genética
14.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 61(3): 263-268, May-Jun/2015.
Artigo em Inglês | LILACS | ID: lil-753178

RESUMO

Summary In southern Brazil, since 1989, several cases of accidents produced by unwilling contact with the body of poisonous caterpillars of the moth species Lonomia obliqua Walker, 1855 (Lepidoptera: Saturniidae), were described. L. obliqua caterpillars have gregarious behavior and feed on leaves of host trees during the night, staying grouped in the trunk during the day, which favors the occurrence of accidents with the species. This caterpillar has the body covered with bristles that on contact with the skin of individuals, breaks and release their contents, inoculating the venom into the victim. The basic constitution of the venom is protein and its components produce physiological changes in the victim, which include disturbances in hemostasis. Hemorrhagic syndrome associated with consumption coagulopathy, intravascular hemolysis and acute renal failure are some of the possible clinical manifestations related to poisoning by L. obliqua. Specific laboratory tests for diagnosis of poisoning have not been described previously. The diagnosis of poisoning is made based on the patient's medical history, clinical manifestations, erythrocyte levels, and, primarily, parameters that evaluate blood coagulation. Treatment is performed with the use of supportive care and the administration of specific hyperimmune antivenom. Poisoning can be serious and even fatal.


Na região Sul do Brasil, a partir de 1989, foram descritos inúmeros casos de contato acidental com o corpo de lagartas venenosas da mariposa da espécie Lonomia obliqua Walker, 1855 (Lepidoptera: Saturniidae). As lagartas de L. obliqua possuem comportamento gregário e alimentam- -se de folhas das árvores hospedeiras durante a noite, permanecendo agrupadas no tronco durante o dia, o que favorece a ocorrência de acidentes. Essa lagarta possui o corpo recoberto por cerdas urticantes, que, ao contato com a pele dos indivíduos, se rompem e liberam seu conteúdo, inoculando o veneno na vítima. A constituição básica do veneno é proteica e seus componentes produzem modificações fisiológicas no acidentado, que incluem distúrbios na hemostasia. Síndrome hemorrágica associada a coagulopatia de consumo, hemólise intravascular e insuficiência renal aguda são algumas das manifestações clínicas possíveis relacionadas ao envenenamento por L. obliqua. Ainda não foram descritas avaliações laboratoriais específicas para diagnóstico do envenenamento, que é feito com base na anamnese do paciente, nas manifestações clínicas, nos índices hematimétricos e, principalmente, nos parâmetros que avaliam a coagulação sanguínea. A terapêutica é feita com a utilização de medidas de suporte e com a administração de um soro heterólogo hiperimune específico. Os envenenamentos podem ser graves e até mesmo fatais.


Assuntos
Animais , Humanos , Venenos de Artrópodes/intoxicação , Hemostasia , Lepidópteros , Venenos de Artrópodes/metabolismo , Coagulação Sanguínea/efeitos dos fármacos , Brasil , Coagulação Intravascular Disseminada/etiologia , Hemorragia/induzido quimicamente , Mariposas , Serina Endopeptidases/metabolismo
15.
Rev. méd. Chile ; 142(7): 880-888, jul. 2014. tab
Artigo em Espanhol | LILACS | ID: lil-726179

RESUMO

Statins are the preferred treatment for hypercholesterolemia and several studies have demonstrated their long-term safety and efficacy in reducing cardiovascular morbidity and mortality. However, in some cases of severe hypercholesterolemia such as homozygous and heterozygous familial hypercholesterolemia or statin intolerant patients, statins can be less efficient. In recent years, new lipid-lowering agents with novel mechanisms of action have been developed to reduce LDL-cholesterol in patients with severe hypercholesterolemia, associated or not to conventional lipid-lowering therapy. These therapies include microsomal transfer protein inhibitor (Lomitapide), antisense oligonucleotide to Apo B100 (Mipomersen) and monoclonal antibodies against Proprotein convertase subtilisin/kexin type 9 (PCSK9). Different studies have shown the great effectiveness of these new therapies. Short-term studies confirmed their adequate security profile, especially in patients with homozygous familiar hypercholesterolemia or severe hypercholesterolemia. Some of these agents have been also tested in statin-intolerant patients. However, long-term studies are needed to evaluate their safety, effectiveness and impact on cardiovascular risk reduction.


Assuntos
Humanos , Anticolesterolemiantes/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Benzimidazóis/uso terapêutico , Ensaios Clínicos como Assunto , Oligonucleotídeos/uso terapêutico , Pró-Proteína Convertases/uso terapêutico , Serina Endopeptidases/uso terapêutico
16.
Trends psychiatry psychother. (Impr.) ; 36(1): 52-58, Jan-Mar/2014. tab
Artigo em Inglês | LILACS | ID: lil-707279

RESUMO

INTRODUCTION: Day hospitals in psychiatry are a major alternative to inpatient care today, acting as key components of community and social psychiatry. Objective: To study trends in the use of psychiatric day hospitals over the last decades of the 20th century and the first decade of the 21st century, focusing on patient age, sex, and diagnostic group, using data from Centro Hospitalar São João, Porto, Portugal. METHODS: Data corresponding to years 1970 to 2009 were collected from patient files. Patients were classified into seven diagnostic groups considering their primary diagnoses only. RESULTS: Mean age upon admission rose from 32.7±12.1 years in the second half of the 1970s to 43.5±12.2 years in 2005-2009 (p for trend < 0.001). Most patients were female (63.2%), however their proportion decreased from nearly 70% in the 1970s to 60% in the first decade of the 21st century. In males, until the late 1980s, neurotic disorders (E) were the most common diagnosis, accounting for more than one third of admissions. In the subsequent years, this proportion decreased, and the number of admissions for schizophrenia (C) exceeded 50% in 2004- 2009. In females, until the late 1980s, affective disorders (D) and neurotic disorders (E), similarly distributed, accounted for most admissions. From the 1990s on, the proportion of neurotic disorders (E) substantially decreased, and affective disorders (D) came to represent more than 50% of all admissions. CONCLUSIONS: Mean age upon admission rose with time, as did the percentage of female admissions, even though the latter tendency weakened in the last 10 years assessed. There was also an increase in the proportion of patients with schizophrenia. .


INTRODUÇÃO: Os hospitais de dia em psiquiatria representam atualmente uma das principais alternativas ao internamento, atuando como componentes chave na psiquiatria comunitária e social. OBJETIVO: Avaliar tendências na utilização de um hospital de dia no período compreendido entre as últimas décadas do século 20 e a primeira década do século 21, com foco em idade, sexo e grupo diagnóstico, usando dados do Centro Hospitalar São João, Porto, Portugal. MÉTODOS: Dados correspondentes aos anos 1970 a 2009 foram coletados dos prontuários clínicos. Os pacientes foram classificados em sete grupos diagnósticos, tendo em conta o diagnóstico principal. Resultados: A idade média na admissão aumentou de 32.7±12.1 anos na segunda metade da década de 1970 para 43.5±12.2 anos em 2005-2009 (p < 0.001). A maioria dos pacientes era do sexo feminino (63.2%), no entanto sua proporção diminuiu de cerca de 70% na década de 1970 para 60% na primeira década do século 21. Nos homens, até o final dos anos 1980, o grupo das perturbações neuróticas (E) era o diagnóstico mais comum, representando mais de um terço das admissões. Durante os anos seguintes, essa proporção diminuiu, e o número de admissões por esquizofrenia (C) alcançou mais de 50% no período de 2004-2009. Nas mulheres, até o final dos anos 1980, as perturbações afetivas (D) e as perturbações neuróticas (E), distribuídas similarmente, respondiam pela maioria das admissões. A partir dos anos 1990, a proporção das perturbações neuróticas (E) diminuiu substancialmente, e as perturbações afetivas (D) passaram a corresponder a mais de 50% do total das admissões. Conclusões: A idade média na admissão ...


Assuntos
Adolescente , Criança , Feminino , Humanos , Masculino , Adulto Jovem , Adenoma/genética , Mutação em Linhagem Germinativa , Síndromes Neoplásicas Hereditárias/genética , Serina Endopeptidases/genética , Neoplasias da Glândula Tireoide/genética , Adenoma/metabolismo , Adenoma/patologia , Predisposição Genética para Doença , Linhagem , Análise de Sequência de DNA , Serina Endopeptidases/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia
17.
Mem. Inst. Oswaldo Cruz ; 109(1): 38-50, 02/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-703647

RESUMO

Transcripts similar to those that encode the nonstructural (NS) proteins NS3 and NS5 from flaviviruses were found in a salivary gland (SG) complementary DNA (cDNA) library from the cattle tick Rhipicephalus microplus. Tick extracts were cultured with cells to enable the isolation of viruses capable of replicating in cultured invertebrate and vertebrate cells. Deep sequencing of the viral RNA isolated from culture supernatants provided the complete coding sequences for the NS3 and NS5 proteins and their molecular characterisation confirmed similarity with the NS3 and NS5 sequences from other flaviviruses. Despite this similarity, phylogenetic analyses revealed that this potentially novel virus may be a highly divergent member of the genus Flavivirus. Interestingly, we detected the divergent NS3 and NS5 sequences in ticks collected from several dairy farms widely distributed throughout three regions of Brazil. This is the first report of flavivirus-like transcripts in R. microplus ticks. This novel virus is a potential arbovirus because it replicated in arthropod and mammalian cells; furthermore, it was detected in a cDNA library from tick SGs and therefore may be present in tick saliva. It is important to determine whether and by what means this potential virus is transmissible and to monitor the virus as a potential emerging tick-borne zoonotic pathogen.


Assuntos
Animais , Bovinos , Flavivirus/química , RNA Viral/isolamento & purificação , Rhipicephalus/virologia , Proteínas não Estruturais Virais/química , Brasil , Sequência Conservada/genética , Flavivirus/classificação , Flavivirus/isolamento & purificação , Biblioteca Gênica , Interações Hidrofóbicas e Hidrofílicas , Filogenia , Reação em Cadeia da Polimerase , RNA Helicases/química , Alinhamento de Sequência/estatística & dados numéricos , Análise de Sequência de Proteína/métodos , Serina Endopeptidases/química , Extratos de Tecidos/análise , Transcriptoma/genética
19.
Braz. j. med. biol. res ; 46(6): 546-554, 02/jul. 2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-679208

RESUMO

Multidrug resistance (MDR) poses a serious impediment to the success of chemotherapy for laryngeal cancer. To identify microRNAs and mRNAs associated with MDR of human laryngeal cancer Hep-2 cells, we developed a multidrug-resistant human laryngeal cancer subline, designated Hep-2/v, by exposing Hep-2 cells to stepwise increasing concentrations of vincristine (0.02-0.96'µM). Microarray assays were performed to compare the microRNA and mRNA expression profiles of Hep-2 and Hep-2/v cells. Compared to Hep-2 cells, Hep-2/v cells were more resistant to chemotherapy drugs (∼45-fold more resistant to vincristine, 5.1-fold more resistant to cisplatin, and 5.6-fold more resistant to 5-fluorouracil) and had a longer doubling time (42.33±1.76 vs 28.75±1.12'h, P<0.05), higher percentage of cells in G0/G1 phase (80.98±0.52 vs 69.14±0.89, P<0.05), increased efflux of rhodamine 123 (95.97±0.56 vs 12.40±0.44%, P<0.01), and up-regulated MDR1 expression. A total of 7 microRNAs and 605 mRNAs were differentially expressed between the two cell types. Of the differentially expressed mRNAs identified, regulator of G-protein signaling 10, high-temperature requirement protein A1, and nuclear protein 1 were found to be the putative targets of the differentially expressed microRNAs identified. These findings may open a new avenue for clarifying the mechanisms responsible for MDR in laryngeal cancer.


Assuntos
Humanos , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Laríngeas/genética , MicroRNAs/isolamento & purificação , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , RNA Mensageiro/isolamento & purificação , Antineoplásicos/farmacologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Citometria de Fluxo , Fluoruracila/farmacologia , Pontos de Checagem da Fase G1 do Ciclo Celular , Genes MDR , Neoplasias Laríngeas/tratamento farmacológico , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas RGS/genética , /farmacocinética , Serina Endopeptidases/genética , Análise Serial de Tecidos , Vincristina/farmacologia
20.
Rio de Janeiro; s.n; 2013. xiv,140 p. ilus, tab, graf, mapas.
Tese em Português | LILACS | ID: lil-746873

RESUMO

Os mosquitos Aedes albopictus (Skuse, 1894) e Aedes aegypti (Linnaeus, 1762) apresentam significativa importância epidemiológica dentro da família Culicidae por serem os principais vetores da febre amarela e dos quatro sorotipos do vírus da dengue. As peptidases ou proteases são enzimas que clivam ligações peptídicas. No sistema digestivo de invertebrados as peptidases, especificamente aquelas da classe das serino-peptidases, são abundantes e participam de vários processos fisiológicos, desempenhando um papel principal na hidrólise de proteínas destinadas à nutrição. Estas enzimas podem apresentar características espécie-específicas e essas diferenças são respostas adaptativas a diferentes estilos de vida, ambientes e habilidade de sobrevivência entre as espécies. Neste trabalho descreve-se a caracterização das atividades proteolíticas detectadas em extratos totais das formas pré-imaginais de A. aegypti e A. albopictus por enzimografia em uma dimensão. A estabilidade da expressão de peptidases nessas espécies foi avaliada pela comparação do perfil proteolítico de formas larvais obtidas de ovos de insetos recém coletados no ambiente com ovos de insetos mantidos em colônia por longo período. Foram também comparados os perfis proteolíticos das pupas com seus respectivos imagos, bem como a estabilidade térmica das peptidases detectadas. Observaram-se complexos perfis de serino-peptidases do tipo tripsina em ambas as espécies vetoras.


Contudo esses perfis apresentam diferenças espécie-específicas e também diferenças entre os distintos estágios evolutivos dentro de uma mesma espécie. Também, neste trabalho, descreve-se a caracterização das atividades proteolíticas detectadas no intestino médio de fêmeas de A. albopictus alimentadas com açúcar bem como o primeiro mapa proteô mico e a identificação de peptidases por eletroforese bi-dimensional e espectrometria de massas neste órgão. São discutidas aqui as estratégias usadas para analisar as peptidases expressas nesse tecido. As proteínas expressas no intestino médio de A. albopictus foram identificadas por similaridade com as sequencias de genoma de A. aegypti e distintas ferramentas bioinformáticas foram usadas para obter informação funcional de muitas dessas sequencias que estão pobremente anotadas. Foram identificadas 59 proteínas entre v Resumo as quais três serino-peptidases, e dessas, duas do tipo tripsina e uma quimiotripsina. Os resultados obtidos nos permitiram atribuir de maneira confiável um local de expressão para os genes de tripsina, tripsina alfa e quimotripsina. Em outras palavras, podemos afirmar que os genes acima mencionados se expressam no intestino médio de fêmeas adultas de A. albopictus alimentadas com açúcar. Este achado representa um pequeno, mas importante passo, para a atribuição funcional, ao nível de proteína, de genes codificantes para serino-peptidases do tipo tripsina e quimiotripsina no gênero Aedes.


The mosquitoes Aedes albopictus (Skuse, 1894) and Aedes aegypti (Linnaeus, 1762) havesignificant epidemiological importance within the family Culicidae because they are themain vectors of the yellow fever virus and the four serotypes of Dengue virus. Peptidasesor proteases are enzymes that hydrolyze peptide bonds. In the digestive system ofinvertebrates, the peptidases, specifically those from the class of serine peptidases, areabundant and participate in various physiological processes, playing a major role in thehydrolysis of proteins destined to nutrition. These enzymes may have species-specificcharacteristics, and such differences reflect adaptive responses to different lifestyles andenvironments. In this work we describe the characterization, using zymography, of theproteolytic activities detected in total extracts of larval forms of A. aegypti and A.albopictus. The stability of expression of peptidases in these species was evaluated bycomparing the proteolytic profile of larval forms obtained from eggs of newly collectedinsects to that from eggs of insect kept in colony for a long period. We also compared theproteolytic profiles of pupae as well as the thermal stability of the peptidases detected.Complex profiles of trypsin-like serine peptidases were observed in both species.


However, these profiles differ between species and also differences between the differentevolutionary stages were detected within the same species. Also, in this work, we describethe characterization of the proteolytic activities detected in the midgut of A. albopictusfemales fed on sugar as well as the first proteome map and proteomic identification ofpeptidases in this organ, using two-dimensional electrophoresis and mass spectrometry.The strategies used to analyze the proteases expressed in this tissue are discussed here. Theproteins expressed in the midgut of A. albopictus were identified by similarity with thegenome sequences of A. aegypti and various bioinformatic tools were used to obtainfunctional information for many of these sequences that are poorly annotated. Weidentified 59 proteins including three serine peptidases, and among these, two types oftrypsin-like and one chymotrypsin. The results obtained here allowed us to reliably assignviiiAbstracta localization for the expression of trypsin, trypsin-alpha and chymotrypsin genes. In otherwords, we can say that the above mentioned genes are expressed in the midgut of adultfemales of A. albopictus fed with sugar. This finding represents a small but important stepfor the functional assignment, at the protein level, of the genes coding for trypsin-like andchymotrypsin serine peptidases of the Aedes genus.


Assuntos
Aedes/classificação , Peptídeo Hidrolases , Proteômica , Serina Endopeptidases , Dengue , Febre Amarela
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