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Luis Ferreira | Universidade de São Paulo - Academia.edu

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Luis Ferreira

Universidade de São Paulo, Departamento de Microbiologia/ ICB-USP, Faculty Member

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Jorge Castillo-Sepúlveda

Universidad de Santiago de Chile

Marymount University

Kansas State University

Norwegian University of Science and Technology

Peter J Forshaw

University of Amsterdam

University of Aberdeen

Ben Gurion University of the Negev

Golden Dawn Research Trust

Université Paris Nanterre

Agostino Paravicini Bagliani

University of Lausanne

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Papers by Luis Ferreira

Biosensor-based selective detection of Zika virus specific antibodies in infected individuals

Biosensors & bioelectronics, Jan 15, 2018

Zika virus (ZIKV) recently emerged as a global threat subsequent to its global spread because it ... more Zika virus (ZIKV) recently emerged as a global threat subsequent to its global spread because it induces microencephaly and other brain damages in infants born to infected mothers. Epidemiological monitoring of infection has been hampered by the absence of reliable serological tests capable to distinguish between ZIKV and other Flavivirus infections, in particular Dengue virus (DENV). As both viruses are transmitted by the same mosquito-species, their distributions largely overlap and reliable serological distinction between the viruses is essential. Here we develop a novel biosensor which is based on recombinant forms of ZIKV non-structural protein 1 (NS1) and the domain III of the envelope protein (EDIII). Using electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV), we demonstrate that in addition to extremely sensitive detection of ZIKV-specific antibodies in serum and saliva, the biosensor promptly distinguished ZIKV and DENV-specific antibodies. Hence, ...

Adjuvant-Mediated Epitope Specificity and Enhanced Neutralizing Activity of Antibodies Targeting Dengue Virus Envelope Protein

Frontiers in Immunology, 2017

Specific Biomarkers Associated With Neurological Complications and Congenital Central Nervous System Abnormalities From Zika Virus-Infected Patients in Brazil

The Journal of infectious diseases, Jul 15, 2017

Zika virus (ZIKV) infections have been linked to different levels of clinical outcomes, ranging f... more Zika virus (ZIKV) infections have been linked to different levels of clinical outcomes, ranging from mild rash and fever to severe neurological complications and congenital malformations. We investigated the clinical and immunological response, focusing on the immune mediators profile in 95 acute ZIKV-infected adult patients from Campinas, Brazil. These patients included 6 pregnant women who later delivered during the course of this study. Clinical observations were recorded during hospitalization. Levels of 45 immune mediators were quantified using multiplex microbead-based immunoassays. Whereas 11.6% of patients had neurological complications, 88.4% displayed mild disease of rash and fever. Several immune mediators were specifically higher in ZIKV-infected patients, and levels of interleukin 10, interferon gamma-induced protein 10 (IP-10), and hepatocyte growth factor differentiated between patients with or without neurological complications. Interestingly, higher levels of interl...

Diarrheagenic Escherichia coli

Brazilian Journal of Microbiology, 2016

Prolonged Shedding of Zika Virus Associated with Congenital Infection

New England Journal of Medicine, 2016

Design, Immune Responses and Anti-Tumor Potential of an HPV16 E6E7 Multi-Epitope Vaccine

PloS one, 2015

Cervical cancer is a common type of cancer among women worldwide and infection with high-risk hum... more Cervical cancer is a common type of cancer among women worldwide and infection with high-risk human papillomavirus (HPVs) types represents the major risk factor for the etiopathogenesis of the disease. HPV-16 is the most frequently identified HPV type in cervical lesions and expression of E6 and E7 oncoproteins is required for the uncontrolled cellular proliferation. In the present study we report the design and experimental testing of a recombinant multi-epitope protein containing immunogenic epitopes of HPV-16 E6 and E7. Tumor preventive assays, based on the engraftment of TC-1 cells in mice, showed that the E6E7 multi-epitope protein induced a full preventive anti-tumor protection in wild-type mice, as well as in mice deficient in expression of CD4+ T cells and TLR4 receptor. Nonetheless, no anti-tumor protection was observed in mice deficient in CD8+ T cells. Also, the vaccine promoted high activation of E6/E7-specific T cells and in a therapeutic-approach, E6E7 protein conferre...

Purification and crystallographic studies of a putative carbohydrate-binding module from the Ruminococcus flavefaciens FD-1 endoglucanase Cel5A

Acta Crystallographica Section F Structural Biology Communications, 2015

Ruminant herbivores meet their carbon and energy requirements from a symbiotic relationship with ... more Ruminant herbivores meet their carbon and energy requirements from a symbiotic relationship with cellulosome-producing anaerobic bacteria that efficiently degrade plant cell-wall polysaccharides. The assembly of carbohydrate-active enzymes (CAZymes) into cellulosomes enhances protein stability and enzyme synergistic interactions. Cellulosomes comprise diverse CAZymes displaying a modular architecture in which a catalytic domain is connected,vialinker sequences, to one or more noncatalytic carbohydrate-binding modules (CBMs). CBMs direct the appended catalytic modules to their target substrates, thus facilitating catalysis. The genome of the ruminal cellulolytic bacteriumRuminococcus flavefaciensstrain FD-1 contains over 200 modular proteins containing the cellulosomal signature dockerin module. One of these is an endoglucanase Cel5A comprising two family 5 glycoside hydrolase catalytic modules (GH5) flanking an unclassified CBM (termed CBM-Rf2) and a C-terminal dockerin. This novel ...

Detection of Penicillin-binding Proteins in the Endosymbiont of the Trypanosomatid Crithidia deanei

The Journal of Eukaryotic Microbiology, 1997

Characterization of enterotoxigenic Escherichia coli from diarrhoeal patients in Bangladesh using phenotyping and genetic profiling

Journal of Medical Microbiology, 2007

A total of 99 isolates out of 370 colonization factor (CF)-positive, well-characterized enterotox... more A total of 99 isolates out of 370 colonization factor (CF)-positive, well-characterized enterotoxigenic Escherichia coli (ETEC) strains belonging to 13 different CF types isolated from diarrhoeal patients admitted to the hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh, were tested. The isolates were selected at random based on expression of the major CFs prevailing in Dhaka, Bangladesh, from 1996 to 1998. These isolates were characterized by O-antigenic serotyping, randomly amplified polymorphic DNA (RAPD) analysis and biochemical fingerprinting using the PhenePlate (PhP) system. The 99 ETEC isolates belonged to 10 O serogroups, the predominant ones being O6 (n=28), O115 (n=20) and O128 (n=20). Most isolates of serogroup O6 (CS1+CS3, 11/14; CS2+CS3, 5/8) belonged to the same PhP/RAPD type (H/f), whereas other isolates of serogroup O6 (n=12) belonged to different PhP/RAPD types (Si/f and F/c). Eleven serogroup O128 (CFA/I) isolates belonged to the sam...

Host and Bacterial Factors Affecting Induction of Immune Responses to Flagellin Expressed by Attenuated Salmonella Vaccine Strains

Infection and Immunity, 2004

Previous observations demonstrated that the delivery of recombinant Salmonella enterica serovar D... more Previous observations demonstrated that the delivery of recombinant Salmonella enterica serovar Dublin strains to mice via mucosal routes did not efficiently activate systemic and secreted antibody responses to either type d flagellin or genetically fused heterologous B-cell epitopes, thus reducing the usefulness of the protein as a carrier of epitopes for vaccine purposes. In this work, we investigated murine systemic and mucosal flagellin immunogenicity after oral immunization with attenuated Salmonella strains. The reduced anti-type d flagellin antibody responses in mice immunized via mucosal routes with three doses of flagellated S. enterica serovar Dublin strains were not caused by oral tolerance and could not be restored by coadministration of a mucosal adjuvant. The induction of antibody responses to Salmonella flagellins was shown to differ according to the genetic background, but not the haplotype, of the mouse lineage. Moreover, BALB/c mice orally immunized with S. enteric...

Clonal relationships among Escherichia coli serogroup O6 isolates based on RAPD

FEMS Microbiology Letters, 2006

Antibody responses against flagellin in mice orally immunized with attenuated Salmonella vaccine strains

Archives of Microbiology, 1999

Salmonella fIagellin has been repeatedly used as a carrier for heterologous peptide epitopes eith... more Salmonella fIagellin has been repeatedly used as a carrier for heterologous peptide epitopes either as a parenterally delivered purified antigen or as a parenterally/orally-administered, flagellated, live, attenuated vaccine. Nonetheless, the ability to induce specific antibody responses against the flagellin moiety, fused or not with heterologous peptide, has not usually been reported in mice orally inoculated with a live, attenuated, flagellated Salmonella strain. In this work we evaluated the immunogenicity of flagellin in mice following oral inoculation with an aroA Salmonella enterica serovar Dublin SL5929 strain, which expressed plasmid-encoded recombinant hybrid flagellin fused to the CTP3 epitope (amino acids 50-64) of cholera toxin B-subunit. In contrast to parenterally immunized mice, no significant CTP3- or flagellin-specific antibody responses either in sera (IgG) or feces (IgA) were detected following repeated oral delivery of the recombinant Salmonella strain to C57BL/6 mice. Similarly, flagellin-specific antibody responses were also not detected in mice immunized with strain SL5930, which expressed a nonhybrid flagellin. The lack of flagellin-specific antibody responses was not associated with deficient Peyer patch colonization or spleen invasion. Moreover, stabilization of the flagellin-coding gene by integration into the host chromosome did not significantly improve flagellin-specific antibody responses following administration by the oral route. Taken together, these results suggest that flagellin does not represent an efficient peptide carrier for activation of antibody responses in mice orally immunized with live, attenuated Salmonella strains.

Combined Vaccine Regimen Based on Parenteral Priming with a DNA Vaccine and Administration of an Oral Booster Consisting of a Recombinant Salmonella enterica Serovar Typhimurium Vaccine Strain for Immunization against Infection with Human-Derived Enterotoxigenic Escherichia coli Strains

Infection and Immunity, 2004

Repeated evidence has demonstrated that combined primer-booster immunization regimens can improve... more Repeated evidence has demonstrated that combined primer-booster immunization regimens can improve both secreted and humoral immune responses to antigens derived from viral, bacterial, and parasitic pathogens. For the present work, we evaluated the synergic serum immunoglobulin G (IgG) and fecal IgA antibody responses elicited in BALB/c mice who were intramuscularly primed with a DNA vaccine, pRECFA, followed by oral boosting with an attenuated Salmonella enterica serovar Typhimurium vaccine (HG3) strain, with both vaccines encoding the structural subunit (CfaB) of the CFA/I fimbriae produced by human-derived enterotoxigenic Escherichia coli (ETEC) strains. The immunological properties of the vaccine regimen were evaluated according to the order of the administered vaccines, the nature of the oral antigen carrier, the age of the vaccinated animals, the interval between the priming and boosting doses, and the amount of injected DNA. The production of gamma interferon and the IgG2a sub...

Disclosing the Tourism Dynamic Packages

This paper describes the Open Tourism Initiative (OTI), exploring its application in tourism, bas... more This paper describes the Open Tourism Initiative (OTI), exploring its application in tourism, based on the Virtual Enterprise (VE) organizational model. It assumes as essential to assure the permanent alignment between a tourism solution and the client’s interests and expectations, which claims for a reliable integration and dynamic networking of the entities providing that solution (the VE). When a member of the VE scheduled to provide a given service is somehow conditioned, unable to participate or has to be disentailed from the network, or due to events not necessarily measurable or deterministic, it is necessary to reconfigure the VE in almost real time. OTI handles dynamic tourism packages under reconfigurable VE environment.

Expression, purification, crystallization and preliminary X-ray analysis of CttA, a putative cellulose-binding protein from Ruminococcus flavefaciens

by Luis Ferreira and Shabir Najmudin

Acta crystallographica. Section F, Structural biology communications, 2015

A number of anaerobic microorganisms produce multi-modular, multi-enzyme complexes termed cellulo... more A number of anaerobic microorganisms produce multi-modular, multi-enzyme complexes termed cellulosomes. These extracellular macromolecular nanomachines are designed for the efficient degradation of plant cell-wall carbohydrates to smaller sugars that are subsequently used as a source of carbon and energy. Cellulolytic strains from the rumens of mammals, such as Ruminococcus flavefaciens, have been shown to have one of the most complex cellulosomal systems known. Cellulosome assembly requires the binding of dockerin modules located in cellulosomal enzymes to cohesin modules located in a macromolecular scaffolding protein. Over 220 genes encoding dockerin-containing proteins have been identified in the R. flavefaciens genome. The dockerin-containing enzymes can be incorporated into the primary scaffoldin (ScaA), which in turn can bind to adaptor scaffoldins (ScaB or ScaC) and subsequently to anchoring scaffoldin (ScaE), thereby attaching the whole complex to the cell surface. However,...

Combined crystal structure of a type-I cohesin, mutation and affinity-binding studies reveal structural determinants of cohesin-dockerin specificity

by Luis Ferreira and Shabir Najmudin

Journal of Biological Chemistry, 2015

Background: Cellulosomal cohesin-dockerin types is reversed in Bacteroides cellulosolvens.

GridBR: The Challenge of Grid Computing

Lecture Notes in Computer Science, 2004

The use of grid computing technology is being boosted in last years by the growing demand of low ... more The use of grid computing technology is being boosted in last years by the growing demand of low cost computing resources and idle computing capacity in collaborative research and development environments. GridBR is a PETROBRAS project done with the collaboration of COPPE/UFRJ and IBM Brazil partnership. This project aims at grid computing technology in the information technology strategy of PETRO-BRAS Research and Development Center (CENPES). The present environment comprises a heterogeneous mix of architectures and operating systems with AIX IBM and Linux workstations providing the required support for collaborative execution of applications. The results of a genetic algorithm optimization application are presented as an example of how to take advantage of the existing grid computing infrastructure at PETROBRAS.

Cell envelope components of Yersinia pestis grown in intraperitoneal diffusion chambers

by Luis Ferreira and Rita Cássia Café Ferreira

Revista de Microbiologia, 1998

ABSTRACT The electrophoretic profiles of penicillin binding proteins (PBPs) and outer membrane pr... more ABSTRACT The electrophoretic profiles of penicillin binding proteins (PBPs) and outer membrane proteins (OMPs) of Yersinia pestis EV 76 were determined following in vivo growth in diffusion chambers implanted in the peritoneal cavity of mice. In contrast to Y. pestis grown under in vitro conditions which activate the low calcium response (LCR) regulon there was no significant qualitative or quantitative change of the PBP profile of Y. pestis cells during growth in diffusion chambers for up to 72 h following implantation in mice. Three OMPs, with molecular weight of 100, 60 and 58 kDa, were expressed in Y. pestis cells grown for 24 h, but not at 48 h or at 72 h, in diffusion chambers. These results indicate that growth of Y. pestis in intraperitoneal diffusion chambers activates genes which might be relevant to the growth in the mammal host.

Ferreira et al CIRP 2013

The aim of this paper is to present a cloudlet architecture for dashboard in Cloud and Ubiquitous... more The aim of this paper is to present a cloudlet architecture for dashboard in Cloud and Ubiquitous Manufacturing. In practice means that, with Cloud Computing adoption, Manufacturing requires management applications where ubiquity and effectiveness are enabled. If ubiquity and resources scalability, availability and capacity can be well supported by cloud, pragmatics instruments are required to support effectiveness. The architecture here presented shows the integration of enriched existing (cloud) services, as instances of resources, with layers of new services towards direct and synchronous communication between users. These Rich Internet Application (RIA) components, here named cloudlets, integration, follow dashboards organization patterns and will be supported by emergent web3.0 interaction technologies. In fact, the paper proposes a new Presentation Layer to be used in UMS and (that may be used) in any multi-layer cloud-based web application.

Validation of long chain fatty acids as markers to estimate diet composition of equines fed on grassland-heathland vegetation components

The main objective of this study was to validate the use of long-chain fatty acids (LCFA) as mark... more The main objective of this study was to validate the use of long-chain fatty acids (LCFA) as markers to estimate diet composition of equines fed with diets composed of herbaceous and woody species. Six crossbreed mares (434±59 kg LW) were divided in 2 groups and each group was fed one of two different diets: D1 100% Lolium perenne, D2 70% L. perenne + 30% heather (Erica spp., Calluna vulgaris). Diet composition was estimated from LCFA concentrations (C22 to C34) in diet and faeces, with (i.e. mean recovery rate of the dietary treatment that the animal belonged to) or without correction for incomplete faecal recoveries using least-squares procedures. Reulsts showed clear differences in the LCFA profiles among diet components. LCFA faecal recovery was in general incomplete and tended to decrease with carbon chain length in a curvilinear fashion (P<0.001) and was affected by diet composition (P<0.001). Results also showed that diet composition was accurately estimated with or wit...

Biosensor-based selective detection of Zika virus specific antibodies in infected individuals

Biosensors & bioelectronics, Jan 15, 2018

Zika virus (ZIKV) recently emerged as a global threat subsequent to its global spread because it ... more Zika virus (ZIKV) recently emerged as a global threat subsequent to its global spread because it induces microencephaly and other brain damages in infants born to infected mothers. Epidemiological monitoring of infection has been hampered by the absence of reliable serological tests capable to distinguish between ZIKV and other Flavivirus infections, in particular Dengue virus (DENV). As both viruses are transmitted by the same mosquito-species, their distributions largely overlap and reliable serological distinction between the viruses is essential. Here we develop a novel biosensor which is based on recombinant forms of ZIKV non-structural protein 1 (NS1) and the domain III of the envelope protein (EDIII). Using electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV), we demonstrate that in addition to extremely sensitive detection of ZIKV-specific antibodies in serum and saliva, the biosensor promptly distinguished ZIKV and DENV-specific antibodies. Hence, ...

Adjuvant-Mediated Epitope Specificity and Enhanced Neutralizing Activity of Antibodies Targeting Dengue Virus Envelope Protein

Frontiers in Immunology, 2017

Specific Biomarkers Associated With Neurological Complications and Congenital Central Nervous System Abnormalities From Zika Virus-Infected Patients in Brazil

The Journal of infectious diseases, Jul 15, 2017

Zika virus (ZIKV) infections have been linked to different levels of clinical outcomes, ranging f... more Zika virus (ZIKV) infections have been linked to different levels of clinical outcomes, ranging from mild rash and fever to severe neurological complications and congenital malformations. We investigated the clinical and immunological response, focusing on the immune mediators profile in 95 acute ZIKV-infected adult patients from Campinas, Brazil. These patients included 6 pregnant women who later delivered during the course of this study. Clinical observations were recorded during hospitalization. Levels of 45 immune mediators were quantified using multiplex microbead-based immunoassays. Whereas 11.6% of patients had neurological complications, 88.4% displayed mild disease of rash and fever. Several immune mediators were specifically higher in ZIKV-infected patients, and levels of interleukin 10, interferon gamma-induced protein 10 (IP-10), and hepatocyte growth factor differentiated between patients with or without neurological complications. Interestingly, higher levels of interl...

Diarrheagenic Escherichia coli

Brazilian Journal of Microbiology, 2016

Prolonged Shedding of Zika Virus Associated with Congenital Infection

New England Journal of Medicine, 2016

Design, Immune Responses and Anti-Tumor Potential of an HPV16 E6E7 Multi-Epitope Vaccine

PloS one, 2015

Cervical cancer is a common type of cancer among women worldwide and infection with high-risk hum... more Cervical cancer is a common type of cancer among women worldwide and infection with high-risk human papillomavirus (HPVs) types represents the major risk factor for the etiopathogenesis of the disease. HPV-16 is the most frequently identified HPV type in cervical lesions and expression of E6 and E7 oncoproteins is required for the uncontrolled cellular proliferation. In the present study we report the design and experimental testing of a recombinant multi-epitope protein containing immunogenic epitopes of HPV-16 E6 and E7. Tumor preventive assays, based on the engraftment of TC-1 cells in mice, showed that the E6E7 multi-epitope protein induced a full preventive anti-tumor protection in wild-type mice, as well as in mice deficient in expression of CD4+ T cells and TLR4 receptor. Nonetheless, no anti-tumor protection was observed in mice deficient in CD8+ T cells. Also, the vaccine promoted high activation of E6/E7-specific T cells and in a therapeutic-approach, E6E7 protein conferre...

Purification and crystallographic studies of a putative carbohydrate-binding module from the Ruminococcus flavefaciens FD-1 endoglucanase Cel5A

Acta Crystallographica Section F Structural Biology Communications, 2015

Ruminant herbivores meet their carbon and energy requirements from a symbiotic relationship with ... more Ruminant herbivores meet their carbon and energy requirements from a symbiotic relationship with cellulosome-producing anaerobic bacteria that efficiently degrade plant cell-wall polysaccharides. The assembly of carbohydrate-active enzymes (CAZymes) into cellulosomes enhances protein stability and enzyme synergistic interactions. Cellulosomes comprise diverse CAZymes displaying a modular architecture in which a catalytic domain is connected,vialinker sequences, to one or more noncatalytic carbohydrate-binding modules (CBMs). CBMs direct the appended catalytic modules to their target substrates, thus facilitating catalysis. The genome of the ruminal cellulolytic bacteriumRuminococcus flavefaciensstrain FD-1 contains over 200 modular proteins containing the cellulosomal signature dockerin module. One of these is an endoglucanase Cel5A comprising two family 5 glycoside hydrolase catalytic modules (GH5) flanking an unclassified CBM (termed CBM-Rf2) and a C-terminal dockerin. This novel ...

Detection of Penicillin-binding Proteins in the Endosymbiont of the Trypanosomatid Crithidia deanei

The Journal of Eukaryotic Microbiology, 1997

Characterization of enterotoxigenic Escherichia coli from diarrhoeal patients in Bangladesh using phenotyping and genetic profiling

Journal of Medical Microbiology, 2007

A total of 99 isolates out of 370 colonization factor (CF)-positive, well-characterized enterotox... more A total of 99 isolates out of 370 colonization factor (CF)-positive, well-characterized enterotoxigenic Escherichia coli (ETEC) strains belonging to 13 different CF types isolated from diarrhoeal patients admitted to the hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh, were tested. The isolates were selected at random based on expression of the major CFs prevailing in Dhaka, Bangladesh, from 1996 to 1998. These isolates were characterized by O-antigenic serotyping, randomly amplified polymorphic DNA (RAPD) analysis and biochemical fingerprinting using the PhenePlate (PhP) system. The 99 ETEC isolates belonged to 10 O serogroups, the predominant ones being O6 (n=28), O115 (n=20) and O128 (n=20). Most isolates of serogroup O6 (CS1+CS3, 11/14; CS2+CS3, 5/8) belonged to the same PhP/RAPD type (H/f), whereas other isolates of serogroup O6 (n=12) belonged to different PhP/RAPD types (Si/f and F/c). Eleven serogroup O128 (CFA/I) isolates belonged to the sam...

Host and Bacterial Factors Affecting Induction of Immune Responses to Flagellin Expressed by Attenuated Salmonella Vaccine Strains

Infection and Immunity, 2004

Previous observations demonstrated that the delivery of recombinant Salmonella enterica serovar D... more Previous observations demonstrated that the delivery of recombinant Salmonella enterica serovar Dublin strains to mice via mucosal routes did not efficiently activate systemic and secreted antibody responses to either type d flagellin or genetically fused heterologous B-cell epitopes, thus reducing the usefulness of the protein as a carrier of epitopes for vaccine purposes. In this work, we investigated murine systemic and mucosal flagellin immunogenicity after oral immunization with attenuated Salmonella strains. The reduced anti-type d flagellin antibody responses in mice immunized via mucosal routes with three doses of flagellated S. enterica serovar Dublin strains were not caused by oral tolerance and could not be restored by coadministration of a mucosal adjuvant. The induction of antibody responses to Salmonella flagellins was shown to differ according to the genetic background, but not the haplotype, of the mouse lineage. Moreover, BALB/c mice orally immunized with S. enteric...

Clonal relationships among Escherichia coli serogroup O6 isolates based on RAPD

FEMS Microbiology Letters, 2006

Antibody responses against flagellin in mice orally immunized with attenuated Salmonella vaccine strains

Archives of Microbiology, 1999

Salmonella fIagellin has been repeatedly used as a carrier for heterologous peptide epitopes eith... more Salmonella fIagellin has been repeatedly used as a carrier for heterologous peptide epitopes either as a parenterally delivered purified antigen or as a parenterally/orally-administered, flagellated, live, attenuated vaccine. Nonetheless, the ability to induce specific antibody responses against the flagellin moiety, fused or not with heterologous peptide, has not usually been reported in mice orally inoculated with a live, attenuated, flagellated Salmonella strain. In this work we evaluated the immunogenicity of flagellin in mice following oral inoculation with an aroA Salmonella enterica serovar Dublin SL5929 strain, which expressed plasmid-encoded recombinant hybrid flagellin fused to the CTP3 epitope (amino acids 50-64) of cholera toxin B-subunit. In contrast to parenterally immunized mice, no significant CTP3- or flagellin-specific antibody responses either in sera (IgG) or feces (IgA) were detected following repeated oral delivery of the recombinant Salmonella strain to C57BL/6 mice. Similarly, flagellin-specific antibody responses were also not detected in mice immunized with strain SL5930, which expressed a nonhybrid flagellin. The lack of flagellin-specific antibody responses was not associated with deficient Peyer patch colonization or spleen invasion. Moreover, stabilization of the flagellin-coding gene by integration into the host chromosome did not significantly improve flagellin-specific antibody responses following administration by the oral route. Taken together, these results suggest that flagellin does not represent an efficient peptide carrier for activation of antibody responses in mice orally immunized with live, attenuated Salmonella strains.

Combined Vaccine Regimen Based on Parenteral Priming with a DNA Vaccine and Administration of an Oral Booster Consisting of a Recombinant Salmonella enterica Serovar Typhimurium Vaccine Strain for Immunization against Infection with Human-Derived Enterotoxigenic Escherichia coli Strains

Infection and Immunity, 2004

Repeated evidence has demonstrated that combined primer-booster immunization regimens can improve... more Repeated evidence has demonstrated that combined primer-booster immunization regimens can improve both secreted and humoral immune responses to antigens derived from viral, bacterial, and parasitic pathogens. For the present work, we evaluated the synergic serum immunoglobulin G (IgG) and fecal IgA antibody responses elicited in BALB/c mice who were intramuscularly primed with a DNA vaccine, pRECFA, followed by oral boosting with an attenuated Salmonella enterica serovar Typhimurium vaccine (HG3) strain, with both vaccines encoding the structural subunit (CfaB) of the CFA/I fimbriae produced by human-derived enterotoxigenic Escherichia coli (ETEC) strains. The immunological properties of the vaccine regimen were evaluated according to the order of the administered vaccines, the nature of the oral antigen carrier, the age of the vaccinated animals, the interval between the priming and boosting doses, and the amount of injected DNA. The production of gamma interferon and the IgG2a sub...

Disclosing the Tourism Dynamic Packages

This paper describes the Open Tourism Initiative (OTI), exploring its application in tourism, bas... more This paper describes the Open Tourism Initiative (OTI), exploring its application in tourism, based on the Virtual Enterprise (VE) organizational model. It assumes as essential to assure the permanent alignment between a tourism solution and the client’s interests and expectations, which claims for a reliable integration and dynamic networking of the entities providing that solution (the VE). When a member of the VE scheduled to provide a given service is somehow conditioned, unable to participate or has to be disentailed from the network, or due to events not necessarily measurable or deterministic, it is necessary to reconfigure the VE in almost real time. OTI handles dynamic tourism packages under reconfigurable VE environment.

Expression, purification, crystallization and preliminary X-ray analysis of CttA, a putative cellulose-binding protein from Ruminococcus flavefaciens

by Luis Ferreira and Shabir Najmudin

Acta crystallographica. Section F, Structural biology communications, 2015

A number of anaerobic microorganisms produce multi-modular, multi-enzyme complexes termed cellulo... more A number of anaerobic microorganisms produce multi-modular, multi-enzyme complexes termed cellulosomes. These extracellular macromolecular nanomachines are designed for the efficient degradation of plant cell-wall carbohydrates to smaller sugars that are subsequently used as a source of carbon and energy. Cellulolytic strains from the rumens of mammals, such as Ruminococcus flavefaciens, have been shown to have one of the most complex cellulosomal systems known. Cellulosome assembly requires the binding of dockerin modules located in cellulosomal enzymes to cohesin modules located in a macromolecular scaffolding protein. Over 220 genes encoding dockerin-containing proteins have been identified in the R. flavefaciens genome. The dockerin-containing enzymes can be incorporated into the primary scaffoldin (ScaA), which in turn can bind to adaptor scaffoldins (ScaB or ScaC) and subsequently to anchoring scaffoldin (ScaE), thereby attaching the whole complex to the cell surface. However,...

Combined crystal structure of a type-I cohesin, mutation and affinity-binding studies reveal structural determinants of cohesin-dockerin specificity

by Luis Ferreira and Shabir Najmudin

Journal of Biological Chemistry, 2015

Background: Cellulosomal cohesin-dockerin types is reversed in Bacteroides cellulosolvens.

GridBR: The Challenge of Grid Computing

Lecture Notes in Computer Science, 2004

The use of grid computing technology is being boosted in last years by the growing demand of low ... more The use of grid computing technology is being boosted in last years by the growing demand of low cost computing resources and idle computing capacity in collaborative research and development environments. GridBR is a PETROBRAS project done with the collaboration of COPPE/UFRJ and IBM Brazil partnership. This project aims at grid computing technology in the information technology strategy of PETRO-BRAS Research and Development Center (CENPES). The present environment comprises a heterogeneous mix of architectures and operating systems with AIX IBM and Linux workstations providing the required support for collaborative execution of applications. The results of a genetic algorithm optimization application are presented as an example of how to take advantage of the existing grid computing infrastructure at PETROBRAS.

Cell envelope components of Yersinia pestis grown in intraperitoneal diffusion chambers

by Luis Ferreira and Rita Cássia Café Ferreira

Revista de Microbiologia, 1998

ABSTRACT The electrophoretic profiles of penicillin binding proteins (PBPs) and outer membrane pr... more ABSTRACT The electrophoretic profiles of penicillin binding proteins (PBPs) and outer membrane proteins (OMPs) of Yersinia pestis EV 76 were determined following in vivo growth in diffusion chambers implanted in the peritoneal cavity of mice. In contrast to Y. pestis grown under in vitro conditions which activate the low calcium response (LCR) regulon there was no significant qualitative or quantitative change of the PBP profile of Y. pestis cells during growth in diffusion chambers for up to 72 h following implantation in mice. Three OMPs, with molecular weight of 100, 60 and 58 kDa, were expressed in Y. pestis cells grown for 24 h, but not at 48 h or at 72 h, in diffusion chambers. These results indicate that growth of Y. pestis in intraperitoneal diffusion chambers activates genes which might be relevant to the growth in the mammal host.

Ferreira et al CIRP 2013

The aim of this paper is to present a cloudlet architecture for dashboard in Cloud and Ubiquitous... more The aim of this paper is to present a cloudlet architecture for dashboard in Cloud and Ubiquitous Manufacturing. In practice means that, with Cloud Computing adoption, Manufacturing requires management applications where ubiquity and effectiveness are enabled. If ubiquity and resources scalability, availability and capacity can be well supported by cloud, pragmatics instruments are required to support effectiveness. The architecture here presented shows the integration of enriched existing (cloud) services, as instances of resources, with layers of new services towards direct and synchronous communication between users. These Rich Internet Application (RIA) components, here named cloudlets, integration, follow dashboards organization patterns and will be supported by emergent web3.0 interaction technologies. In fact, the paper proposes a new Presentation Layer to be used in UMS and (that may be used) in any multi-layer cloud-based web application.

Validation of long chain fatty acids as markers to estimate diet composition of equines fed on grassland-heathland vegetation components

The main objective of this study was to validate the use of long-chain fatty acids (LCFA) as mark... more The main objective of this study was to validate the use of long-chain fatty acids (LCFA) as markers to estimate diet composition of equines fed with diets composed of herbaceous and woody species. Six crossbreed mares (434±59 kg LW) were divided in 2 groups and each group was fed one of two different diets: D1 100% Lolium perenne, D2 70% L. perenne + 30% heather (Erica spp., Calluna vulgaris). Diet composition was estimated from LCFA concentrations (C22 to C34) in diet and faeces, with (i.e. mean recovery rate of the dietary treatment that the animal belonged to) or without correction for incomplete faecal recoveries using least-squares procedures. Reulsts showed clear differences in the LCFA profiles among diet components. LCFA faecal recovery was in general incomplete and tended to decrease with carbon chain length in a curvilinear fashion (P<0.001) and was affected by diet composition (P<0.001). Results also showed that diet composition was accurately estimated with or wit...