43 research outputs found
Análise comparativa do transcritoma de dois estágios no desenvolvimento do parasito cestódeo Mesocestoides corti
O desenvolvimento em cestódeos abrange mudanças fisiológicas e morfológicas complexas. Com o intuito de ganhar conhecimento nos mecanismos moleculares que regulam este processo, foi realizada uma análise exaustiva da expressão de microRNAs e genes em dois estágios do desenvolvimento (tetratirídeo e verme estrobilado) do cestódeo Mesocestoides corti. Utilizando uma abordagem de sequenciamento de alto rendimento, foi identificada evidencia transcricional para 42 loci de microRNAs, assim como microRNAs diferencialmente expressos ou estágios específicos. Além disso, foi demonstrado que a uridilação é um mecanismo de modificação pós-transcricional diferencial presente nos microRNAs de M. corti. O conjunto completo de microRNAs de M. corti identificado representa 33 famílias únicas, e confirma a notável perda de famílias de microRNAs conservadas dentro do grupo de platelmintos parasitos. O transcritôma de M. corti foi obtido utilizando uma abordagem baseada em sequenciamento de RNA. Foram evidenciados 19,053 transcritos, incluindo isoformas e genes previamente não anotados. Foram identificados um total de 66 transcritos específicos de tetratirídeo e 136 específicos de verme estrobilado, assim como genes diferencialmente expressos (342 e 559 respectivamente), sugerindo regulação de caraterísticas específicas de cada estágio. A analise de expressão diferencial e enriquecimento de termos GO refletem os processos biológicos associados a cada estágio, sendo o tetratirídeo capaz de reproduzirse assexuadamente e migrar através dos tecidos do hospedeiro intermediário, e o verme estrobilado de maturar e reproduzir-se sexuadamente no hospedeiro definitivo. Globalmente, os resultados apresentados fornecem uma plataforma para estudos de novos mecanismos moleculares da regulação gênica póstranscricional baseados em microRNAs em cestódeos, necessários para a elucidação de aspectos do desenvolvimento da complexa biologia destes parasitos. Além disso, este trabalho significativamente contribui ao conhecimento do perfil de expressão gênica de M. corti aumentando o número de transcritos sequenciados identificados através da anotação funcional de vários genes.Cestode development involves complex morphological and physiological changes. To gain knowledge in the molecular pathways that regulate this process, a comprehensive analysis of microRNAs and genes expressed in two developmental stages (tetrathyridium and strobilated worm) of the model cestode Mesocestoides corti was performed. Using a high-throughput sequencing approach, transcriptional evidence of 42 microRNA loci, as well as differentially expressed and stage-specific miRNAs between these developmental stages were found. Moreover, it was shown that uridylation is a differential mechanism of post-transcriptional modification of M. corti microRNAs. The whole set of M. corti microRNAs represent 33 unique miRNA families, and confirm the remarkable loss of conserved miRNA families within platyhelminth parasites. The M. corti transcriptome was obtained through a RNA-seq-based approach. Transcriptional evidence for 19,053 transcripts was found, including isoforms and previously not annotated genes. A total of 66 tetrathyridium and 136 strobilatedspecific transcripts were found, as well as differentially expressed genes (342 and 559, respectively), suggesting regulation of stage-specific features. Differential expression and GO term enrichment analysis reflects the biological processes associated with each stage, the tetrathyridium stage being able to reproduce asexually and actively migrate through the intermediate host tissue; and the strobilated worm that undergoes sexual maduration and reproduction in the definitive host. Overall, the presented results provide a valuable platform to studies aiming to identify and characterize novel miRNA-based molecular mechanisms of post-transcriptional gene regulation in cestodes, necessary for the elucidation of developmental aspects of the complex biology of these parasites. In addition, this work significantly contributes to the knowledge of the gene expression profile of M. corti by increasing the number of sequenced transcripts identified and through functional annotation of several genes
Identification of Thioredoxin Glutathione Reductase Inhibitors That Kill Cestode and Trematode Parasites
Parasitic flatworms are responsible for serious infectious diseases that affect humans as well as livestock animals in vast regions of the world. Yet, the drug armamentarium available for treatment of these infections is limited: praziquantel is the single drug currently available for 200 million people infected with Schistosoma spp. and there is justified concern about emergence of drug resistance. Thioredoxin glutathione reductase (TGR) is an essential core enzyme for redox homeostasis in flatworm parasites. In this work, we searched for flatworm TGR inhibitors testing compounds belonging to various families known to inhibit thioredoxin reductase or TGR and also additional electrophilic compounds. Several furoxans and one thiadiazole potently inhibited TGRs from both classes of parasitic flatworms: cestoda (tapeworms) and trematoda (flukes), while several benzofuroxans and a quinoxaline moderately inhibited TGRs. Remarkably, five active compounds from diverse families possessed a phenylsulfonyl group, strongly suggesting that this moiety is a new pharmacophore. The most active inhibitors were further characterized and displayed slow and nearly irreversible binding to TGR. These compounds efficiently killed Echinococcus granulosus larval worms and Fasciola hepatica newly excysted juveniles in vitro at a 20 µM concentration. Our results support the concept that the redox metabolism of flatworm parasites is precarious and particularly susceptible to destabilization, show that furoxans can be used to target both flukes and tapeworms, and identified phenylsulfonyl as a new drug-hit moiety for both classes of flatworm parasites
Análise comparativa do transcritoma de dois estágios no desenvolvimento do parasito cestódeo Mesocestoides corti
O desenvolvimento em cestódeos abrange mudanças fisiológicas e morfológicas complexas. Com o intuito de ganhar conhecimento nos mecanismos moleculares que regulam este processo, foi realizada uma análise exaustiva da expressão de microRNAs e genes em dois estágios do desenvolvimento (tetratirídeo e verme estrobilado) do cestódeo Mesocestoides corti. Utilizando uma abordagem de sequenciamento de alto rendimento, foi identificada evidencia transcricional para 42 loci de microRNAs, assim como microRNAs diferencialmente expressos ou estágios específicos. Além disso, foi demonstrado que a uridilação é um mecanismo de modificação pós-transcricional diferencial presente nos microRNAs de M. corti. O conjunto completo de microRNAs de M. corti identificado representa 33 famílias únicas, e confirma a notável perda de famílias de microRNAs conservadas dentro do grupo de platelmintos parasitos. O transcritôma de M. corti foi obtido utilizando uma abordagem baseada em sequenciamento de RNA. Foram evidenciados 19,053 transcritos, incluindo isoformas e genes previamente não anotados. Foram identificados um total de 66 transcritos específicos de tetratirídeo e 136 específicos de verme estrobilado, assim como genes diferencialmente expressos (342 e 559 respectivamente), sugerindo regulação de caraterísticas específicas de cada estágio. A analise de expressão diferencial e enriquecimento de termos GO refletem os processos biológicos associados a cada estágio, sendo o tetratirídeo capaz de reproduzirse assexuadamente e migrar através dos tecidos do hospedeiro intermediário, e o verme estrobilado de maturar e reproduzir-se sexuadamente no hospedeiro definitivo. Globalmente, os resultados apresentados fornecem uma plataforma para estudos de novos mecanismos moleculares da regulação gênica póstranscricional baseados em microRNAs em cestódeos, necessários para a elucidação de aspectos do desenvolvimento da complexa biologia destes parasitos. Além disso, este trabalho significativamente contribui ao conhecimento do perfil de expressão gênica de M. corti aumentando o número de transcritos sequenciados identificados através da anotação funcional de vários genes.Cestode development involves complex morphological and physiological changes. To gain knowledge in the molecular pathways that regulate this process, a comprehensive analysis of microRNAs and genes expressed in two developmental stages (tetrathyridium and strobilated worm) of the model cestode Mesocestoides corti was performed. Using a high-throughput sequencing approach, transcriptional evidence of 42 microRNA loci, as well as differentially expressed and stage-specific miRNAs between these developmental stages were found. Moreover, it was shown that uridylation is a differential mechanism of post-transcriptional modification of M. corti microRNAs. The whole set of M. corti microRNAs represent 33 unique miRNA families, and confirm the remarkable loss of conserved miRNA families within platyhelminth parasites. The M. corti transcriptome was obtained through a RNA-seq-based approach. Transcriptional evidence for 19,053 transcripts was found, including isoforms and previously not annotated genes. A total of 66 tetrathyridium and 136 strobilatedspecific transcripts were found, as well as differentially expressed genes (342 and 559, respectively), suggesting regulation of stage-specific features. Differential expression and GO term enrichment analysis reflects the biological processes associated with each stage, the tetrathyridium stage being able to reproduce asexually and actively migrate through the intermediate host tissue; and the strobilated worm that undergoes sexual maduration and reproduction in the definitive host. Overall, the presented results provide a valuable platform to studies aiming to identify and characterize novel miRNA-based molecular mechanisms of post-transcriptional gene regulation in cestodes, necessary for the elucidation of developmental aspects of the complex biology of these parasites. In addition, this work significantly contributes to the knowledge of the gene expression profile of M. corti by increasing the number of sequenced transcripts identified and through functional annotation of several genes
Contribución a la dilucidación de los mecanismos proteolíticos que operan en la digestión intestinal del trematodo parásito Fasciola hepatica
Orientador: Dr. Carlos Carmona, co-orientador Dr. José F. Tor
INVESTIGATION OF SUGAR CANE BAGASSE ASH AS A BINDING MATERIAL FOR THE CONSTRUCTION INDUSTRY
Sugarcane bagasse ash (SCBA) is a byproduct of the sugar factories produced after burning sugarcane bagasse in the production of electricity. The sugarcane bagasse is produced after the extraction of all economical sugar from sugarcane. The disposal of this material is a common environmental problem in factories producing electricity from sugarcane. In Kakira Sugar Limited (KSL) about 61,000 tons / yr. of SCBA is produced and only about 30,000 tons / yr of this is utilized, and the remaining is damped which becomes an environmental hazard. This research was, conducted to examine the potential of bagasse ash as a cement replacing material in construction industry. Bagasse ash samples were collected from KSL and its chemical properties were investigated. The compressive strength of mortars containing ordinary Portland cement and SCBA in proportions of 0%, 10%, 15%, 20%, 25%, 30% and 40% as a cement replacement were investigated. Three replicates with the bagasse ash replacing ordinary Portland cement in the above mentioned proportions were prepared and tested. The results showed that ordinary Portland cement can be replaced by SCBA up to 20% without affecting the compressive strength of the mortar at a test age of 28 days. These findings suggest that replacement of cement with SCBA could results in the reduction in cost of construction
Identification and profiling of microRNAs in two developmental stages of the model cestode parasite Mesocestoides corti
MicroRNAs (miRNAs), a class of small non-coding RNAs, are key regulators of gene expression at post-transcriptional level and play essential roles in fundamental biological processes such as metabolism and development. The particular developmental characteristics of cestode parasites highlight the importance of studying miRNA gene regulation in these organisms. Here, we performed a comprehensive analysis of miRNAs in two developmental stages of the model cestode Mesocestoides corti. Using a high-throughput sequencing approach, we found transcriptional evidence of 42 miRNA loci in tetrathyridia larvae and strobilated worms. Tetrathyridium and strobilated worm-specific miRNAs were found, as well as differentialy expressed miRNAs between these developmental stages, suggesting miRNA regulation of stage-specific features. Moreover, it was shown that uridylation is a differential mechanism of post-transcriptional modification of M. corti miRNAs. The whole set of M. corti miRNAs represent 33 unique miRNA families, and confirm the remarkable loss of conserved miRNA families within platyhelminth parasites, reflecting their relatively low morphological complexity and high adaptation to parasitism. Overall, the presented results provide a valuable platform to studies aiming to identify and characterize novel miRNA-based molecular mechanisms of post-transcriptional gene regulation in cestodes, necessary for the elucidation of developmental aspects of the complex biology of these parasites.Fil: Basika, Tatiana. Universidade Federal do Rio Grande do Sul; BrasilFil: Macchiaroli, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Cucher, Marcela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Espínola, Sergio Martín. Universidade Federal do Rio Grande do Sul; BrasilFil: Kamenetzky, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Zaha, Arnaldo. Universidade Federal do Rio Grande do Sul; BrasilFil: Rosenzvit, Mara Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Ferreira, Henrique B.. Universidade Federal do Rio Grande do Sul; Brasi