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Pedro Pereira

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University of Zagreb

Uppsala University

University of East London

University of Leicester

Gwen Robbins Schug

University of North Carolina at Greensboro

Gabriel Gutierrez-Alonso

University of Salamanca

Macquarie University

Universidade Federal do Rio Grande do Sul

Swansea University

Jesper Hoffmeyer

University of Copenhagen

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Papers by Pedro Pereira

Optimization Based Design of VCOs with Tapered Inductors

Determination of Volatile Organic Compounds in Groundwater by GC: Comparison Between Headspace and Purge and Trap

Energy Sources, 1998

Two methods for determining fuel contamination in groundwaters are compared. The first is based o... more Two methods for determining fuel contamination in groundwaters are compared. The first is based on headspace extraction, while the other utilizes purge and trap. Analyses, in both cases, are made by gas chromatography/flame ionization detection, with benzene, toluene, and xylene isomers as monitoring agents for fuel leaks. When compared, results show satisfactory agreement if we take into account the high

Metaheuristic Algorithms Comparison for the LC-Voltage Controlled Oscillators Optimal Design

ABSTRACT The goal of this paper is to present a comparison among three known metaheuristics: Gene... more ABSTRACT The goal of this paper is to present a comparison among three known metaheuristics: Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Simulated Annealing (SA). For the comparison, the design of an LC - Voltage Controlled Oscillator (LC-VCO) is considered, where the minimization of both VCO phase noise and power consumption is envisaged. The objective of this comparison is to find the algorithm yielding the best solution. The validity of the solution obtained with each metaheuristic algorithm is checked against HSPICE/RF simulation results. Robustness checks for each algorithm are presented at the end of this paper.

A Multi-objective Simulation Based Tool: Application to the Design of High Performance LC-VCOs

IFIP Advances in Information and Communication Technology, 2013

LC-VCO design methodology based on evolutionary algorithms

2012 International Conference on Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design, SMACD 2012, 2012

ABSTRACT In his paper the design of LC-VCOs is addressed. Due to the high-density integration nee... more ABSTRACT In his paper the design of LC-VCOs is addressed. Due to the high-density integration needs as well as to low cost fabrication, RF applications are usually implemented in CMOS technology. However, this technology development brought up several issues such as the degradation of on-chip LC tank quality factor, yielding VCO&#39;s phase noise limitation. To overcome phase-noise limitations, optimization design methodologies are usually used. Since electromagnetic simulations are timely expensive, model based approaches are needed. In this work the characterization of the oscillator behaviour is guaranteed by a set of analytical models describing each circuit element performance. A set of working examples for UMC130 technology, aiming the VCO phase noise and power consumption optimization, is addressed. The results presented, spotlight the potential of the proposed design methodology, combined with a GA optimization procedure, for an accurate and timely efficient oscillator design. The accuracy of the results is checked against HSPICE/RF simulator.

Weather monitoring system for renewable energy power production correlation

IFIP Advances in Information and Communication Technology, 2011

This work describes the development of a system designed for renewable power generation integrati... more This work describes the development of a system designed for renewable power generation integration. It continuously acquires wind, solar and temperature data, which is automatically correlated with energy parameters, obtained from renewable energy systems. The developed system was installed in an urban building equipped with photovoltaic cells and wind renewable generation. To validate the developed application, it was analyzed data of a wind generator and a set of photovoltaic panels, installed near to the weather station. The developed application allows, in addition to the acquisition of weather and energy data, their continuous monitoring and correlation through a graphical user interface, providing a friendly interactivity with the user.

Association of Class II Division 2 malocclusion with dental development anomalies | Associação da má oclusão de Classe II Divisão 2 com anomalias do desenvolvimento dentário

Revista Portuguesa de Estomatologia, Medicina Dentaria e Cirurgia Maxilofacial, 2012

GADISI - Genetic algorithms applied to the automatic design of integrated spiral inductors

IFIP Advances in Information and Communication Technology, 2010

This work introduces a tool for the optimization of CMOS integrated spiral inductors. The main ob... more This work introduces a tool for the optimization of CMOS integrated spiral inductors. The main objective of this tool is to offer designers a first approach for the determination of the inductor layout parameters. The core of the tool is a Genetic Algorithm (GA) optimization procedure where technology constraints on the inductor layout parameters are considered. Further constraints regarding inductor design heuristics are also accounted for. Since the layout parameters are inherently discrete due to technology and topology constraints, discrete variable optimization techniques are used. The Matlab GA toolbox is used and the modifications on the GA functions, yielding technology feasible solutions is presented. For the sake of efficiency and simplicity the pi-model is used for characterizing the inductor. The validity of the design results obtained with the tool, is checked against circuit simulation with ASITIC.

Optimization-based design of nano-CMOS LC-VCOs

IFIP Advances in Information and Communication Technology, 2012

... Cox Csi Metal Width Metal Thickness Rsi Ls Rs Length Davg Cs ... IEEE Journal on Emerging and... more

LC-VCO design challenges in the nano-era

Lecture Notes in Electrical Engineering, 2013

ABSTRACT The progressive scaling of CMOS technology towards nanometre sizes has made the implemen... more ABSTRACT The progressive scaling of CMOS technology towards nanometre sizes has made the implementation of highly integrated systems for the wireless communication systems possible. Additionally, higher speed, lower power consumption and area reduction has been reached. Due to the high-density integration needs, as well as to low cost fabrication, RF applications, such as the LC-voltage controlled oscillator (LC-VCO), are usually implemented in CMOS technology. The complexity of designing LC-VCOs has lead to the development of several design methodologies. This chapter introduces an optimization based methodology for the design of LC-VCOs, where its efficiency is granted by the use of analytical models to characterize the active and passive elements’ behaviour.

Structural Basis for Host Membrane Remodeling Induced by Protein 2B of Hepatitis A Virus

Journal of virology, Jan 14, 2015

The complexity of viral RNA synthesis and the numerous participating factors require a mechanism ... more The complexity of viral RNA synthesis and the numerous participating factors require a mechanism to topologically coordinate and concentrate these multiple viral and cellular components, ensuring a concerted function. Similar to all other positive-strand RNA viruses, picornaviruses induce rearrangements of host intracellular membranes to create structures, which act as functional scaffolds for genome replication. The membrane-targeting proteins 2B, 2C, their precursor 2BC, and protein 3A appear primarily involved in membrane remodeling. Little is known about the structure of these proteins and the mechanisms by which they induce massive membrane remodeling. Here we report the crystal structure of the soluble region of hepatitis A virus (HAV) protein 2B, consisting of two domains: a C-terminal helical bundle, preceded by a N-terminal curved five-stranded anti-parallel β-sheet that displays striking structural similarity to the β-barrel domain of enteroviral 2A proteins. Moreover, the...

Effects of food restriction on synthesis and expression of brain-derived neurotrophic factor and tyrosine kinase B in dentate gyrus granule cells of adult rats

Neuroscience Letters, 2006

We have previously found that the dendritic trees of dentate gyrus granule cells are selectively ... more We have previously found that the dendritic trees of dentate gyrus granule cells are selectively vulnerable to food restriction but there are reorganizational morphological events that minimize functional impairments. As the neurotrophin brain-derived neurotrophic factor (BDNF) and the cognate receptor tyrosine kinase B (TrkB) are involved in the maintenance of the structure of dendritic trees, we thought of interest to

Spectrofluorimetric determination of formaldehyde in air after collection onto silica cartridges coated with Fluoral P

Microchemical Journal, 2004

The calibration curve obtained with concentrations of formaldehyde in the range of 12 to 192 ng m... more

[Comparative study of manual vacuum aspiration and uterine curettage for treatment of abortion]

Revista da Associação Médica Brasileira (1992)

To compare manual vacuum aspiration (MVA) and uterine curettage (D and C) for first trimester abo... more To compare manual vacuum aspiration (MVA) and uterine curettage (D and C) for first trimester abortions, in terms of the efficiency of eliminating ovular remnants, frequency of complications, duration of the procedure, and duration of patients' hospitalization. In a prospective study, 50 patients in the MVA group and 50 in the D&C group were randomly included. Inclusion criteria were: spontaneous abortion, gestational age less than 13 weeks, patent cervix, endometrial thickness >15 mm, afebrile state, and hemoglobin >10 g/dl. Blood samples were collected before and after surgical procedures for control of hemoglobin levels. Anesthesia was performed in all cases. The time required for each surgical procedure was recorded. Groups were similar regarding gestational age (9.93 +/- 2.40 vs 9.73 +/- 2.58 weeks; p = 0.71) and endometrial thickness before surgery (22.14 +/- 4.80 vs 22.68 +/- 5.68 mm; p = 0.65). There were no surgical or anesthetic complications in either group. Dur...

Fluorescent reporters for studies of cellular localization of proteins in Staphylococcus aureus

Applied and environmental microbiology, 2010

We have constructed a set of plasmids that allow expression, from their native chromosomal loci, ... more We have constructed a set of plasmids that allow expression, from their native chromosomal loci, of Staphylococcus aureus proteins fused to one of four different fluorescent proteins (green fluorescent protein [GFP], cyan fluorescent protein [CFP], yellow fluorescent protein [YFP], and mCherry), using two different resistance markers (kanamycin and erythromycin). We have also constructed a plasmid that allows expression of proteins from the ectopic spa locus in the S. aureus chromosome. This toolbox can be used for studies of the localization of proteins in S. aureus, a prominent pathogen in both health care and community settings.

Bacterial autolysins trim cell surface peptidoglycan to prevent detection by the Drosophila innate immune system

eLife, 2014

Bacteria have to avoid recognition by the host immune system in order to establish a successful i... more Bacteria have to avoid recognition by the host immune system in order to establish a successful infection. Peptidoglycan, the principal constituent of virtually all bacterial surfaces, is a specific molecular signature recognized by dedicated host receptors, present in animals and plants, which trigger an immune response. Here we report that autolysins from Gram-positive pathogenic bacteria, enzymes capable of hydrolyzing peptidoglycan, have a major role in concealing this inflammatory molecule from Drosophila peptidoglycan recognition proteins (PGRPs). We show that autolysins trim the outermost peptidoglycan fragments and that in their absence bacterial virulence is impaired, as PGRPs can directly recognize leftover peptidoglycan extending beyond the external layers of bacterial proteins and polysaccharides. The activity of autolysins is not restricted to the producer cells but can also alter the surface of neighboring bacteria, facilitating the survival of the entire population in...

The unique regulation of iron-sulfur cluster biogenesis in a Gram-positive bacterium

Proceedings of the National Academy of Sciences of the United States of America, Jan 3, 2014

Iron-sulfur clusters function as cofactors of a wide range of proteins, with diverse molecular ro... more Iron-sulfur clusters function as cofactors of a wide range of proteins, with diverse molecular roles in both prokaryotic and eukaryotic cells. Dedicated machineries assemble the clusters and deliver them to the final acceptor molecules in a tightly regulated process. In the prototypical Gram-negative bacterium Escherichia coli, the two existing iron-sulfur cluster assembly systems, iron-sulfur cluster (ISC) and sulfur assimilation (SUF) pathways, are closely interconnected. The ISC pathway regulator, IscR, is a transcription factor of the helix-turn-helix type that can coordinate a [2Fe-2S] cluster. Redox conditions and iron or sulfur availability modulate the ligation status of the labile IscR cluster, which in turn determines a switch in DNA sequence specificity of the regulator: cluster-containing IscR can bind to a family of gene promoters (type-1) whereas the clusterless form recognizes only a second group of sequences (type-2). However, iron-sulfur cluster biogenesis in Gram-p...

Characterization of binding epitopes of CA125 monoclonal antibodies

Journal of proteome research, Jan 3, 2014

The most used cancer serum biomarker is the CA125 immunoassay for ovarian cancer that detects the... more The most used cancer serum biomarker is the CA125 immunoassay for ovarian cancer that detects the mucin glycoprotein MUC16. Several monoclonal antibodies (mAbs) including OC125 and M11 are used in CA125 assays. However, despite considerable efforts, our knowledge of the molecular characteristics of the recognized epitopes and the role played by glycosylation has remained elusive. Here a comprehensive set of recombinant MUC16 tandem repeats (TRs) expressed in glycoengineered mammalian cells and E. coli, together with overlapping peptides, was used to probe antigen-binding epitopes. We present a complete analysis of N- and O-glycosylation sites of a MUC16 TR expressed in CHO cells and demonstrate that neither N- nor O-glycosylation appear to substantially influence binding of OC125 and M11 mAbs. A series of successive N- and C-terminal truncations of a MUC16 TR construct expressed in E. coli narrowed down the epitopes for OC125 and M11 to a segment containing parts of two consecutive ...

Carriage of Clostridium difficile in free-living South American coati (Nasua nasua) in Brazil

Anaerobe, 2014

The objective of this study was to isolate and characterize Clostridium difficile strains in stoo... more The objective of this study was to isolate and characterize Clostridium difficile strains in stool samples from a wild urban mammal, a South American coati (Nasua nasua) in Brazil. Forty-six free-living N. nasua were trapped, and stool samples were collected. C. difficile was isolated from three (6.5%) sampled animals, two strains were toxigenic (A+B+CDT-, PCR ribotype 014/020 and 106) and one was non toxigenic (A-B-CDT-, PCR ribotype 053). The present work confirms that ring-tailed coati (N. nasua) could harbor C. difficile strains, including those PCR ribotypes commonly reported in C. difficile infection in humans.

Pancreatic neuroendocrine tumour simulating an intraductal papillary mucinous neoplasm

Digestive and liver disease : official journal of the Italian Society of Gastroenterology and the Italian Association for the Study of the Liver, Jan 18, 2014

Optimization Based Design of VCOs with Tapered Inductors

Determination of Volatile Organic Compounds in Groundwater by GC: Comparison Between Headspace and Purge and Trap

Energy Sources, 1998

Two methods for determining fuel contamination in groundwaters are compared. The first is based o... more Two methods for determining fuel contamination in groundwaters are compared. The first is based on headspace extraction, while the other utilizes purge and trap. Analyses, in both cases, are made by gas chromatography/flame ionization detection, with benzene, toluene, and xylene isomers as monitoring agents for fuel leaks. When compared, results show satisfactory agreement if we take into account the high

Metaheuristic Algorithms Comparison for the LC-Voltage Controlled Oscillators Optimal Design

ABSTRACT The goal of this paper is to present a comparison among three known metaheuristics: Gene... more ABSTRACT The goal of this paper is to present a comparison among three known metaheuristics: Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Simulated Annealing (SA). For the comparison, the design of an LC - Voltage Controlled Oscillator (LC-VCO) is considered, where the minimization of both VCO phase noise and power consumption is envisaged. The objective of this comparison is to find the algorithm yielding the best solution. The validity of the solution obtained with each metaheuristic algorithm is checked against HSPICE/RF simulation results. Robustness checks for each algorithm are presented at the end of this paper.

A Multi-objective Simulation Based Tool: Application to the Design of High Performance LC-VCOs

IFIP Advances in Information and Communication Technology, 2013

LC-VCO design methodology based on evolutionary algorithms

2012 International Conference on Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design, SMACD 2012, 2012

ABSTRACT In his paper the design of LC-VCOs is addressed. Due to the high-density integration nee... more ABSTRACT In his paper the design of LC-VCOs is addressed. Due to the high-density integration needs as well as to low cost fabrication, RF applications are usually implemented in CMOS technology. However, this technology development brought up several issues such as the degradation of on-chip LC tank quality factor, yielding VCO&#39;s phase noise limitation. To overcome phase-noise limitations, optimization design methodologies are usually used. Since electromagnetic simulations are timely expensive, model based approaches are needed. In this work the characterization of the oscillator behaviour is guaranteed by a set of analytical models describing each circuit element performance. A set of working examples for UMC130 technology, aiming the VCO phase noise and power consumption optimization, is addressed. The results presented, spotlight the potential of the proposed design methodology, combined with a GA optimization procedure, for an accurate and timely efficient oscillator design. The accuracy of the results is checked against HSPICE/RF simulator.

Weather monitoring system for renewable energy power production correlation

IFIP Advances in Information and Communication Technology, 2011

This work describes the development of a system designed for renewable power generation integrati... more This work describes the development of a system designed for renewable power generation integration. It continuously acquires wind, solar and temperature data, which is automatically correlated with energy parameters, obtained from renewable energy systems. The developed system was installed in an urban building equipped with photovoltaic cells and wind renewable generation. To validate the developed application, it was analyzed data of a wind generator and a set of photovoltaic panels, installed near to the weather station. The developed application allows, in addition to the acquisition of weather and energy data, their continuous monitoring and correlation through a graphical user interface, providing a friendly interactivity with the user.

Association of Class II Division 2 malocclusion with dental development anomalies | Associação da má oclusão de Classe II Divisão 2 com anomalias do desenvolvimento dentário

Revista Portuguesa de Estomatologia, Medicina Dentaria e Cirurgia Maxilofacial, 2012

GADISI - Genetic algorithms applied to the automatic design of integrated spiral inductors

IFIP Advances in Information and Communication Technology, 2010

This work introduces a tool for the optimization of CMOS integrated spiral inductors. The main ob... more This work introduces a tool for the optimization of CMOS integrated spiral inductors. The main objective of this tool is to offer designers a first approach for the determination of the inductor layout parameters. The core of the tool is a Genetic Algorithm (GA) optimization procedure where technology constraints on the inductor layout parameters are considered. Further constraints regarding inductor design heuristics are also accounted for. Since the layout parameters are inherently discrete due to technology and topology constraints, discrete variable optimization techniques are used. The Matlab GA toolbox is used and the modifications on the GA functions, yielding technology feasible solutions is presented. For the sake of efficiency and simplicity the pi-model is used for characterizing the inductor. The validity of the design results obtained with the tool, is checked against circuit simulation with ASITIC.

Optimization-based design of nano-CMOS LC-VCOs

IFIP Advances in Information and Communication Technology, 2012

... Cox Csi Metal Width Metal Thickness Rsi Ls Rs Length Davg Cs ... IEEE Journal on Emerging and... more

LC-VCO design challenges in the nano-era

Lecture Notes in Electrical Engineering, 2013

ABSTRACT The progressive scaling of CMOS technology towards nanometre sizes has made the implemen... more ABSTRACT The progressive scaling of CMOS technology towards nanometre sizes has made the implementation of highly integrated systems for the wireless communication systems possible. Additionally, higher speed, lower power consumption and area reduction has been reached. Due to the high-density integration needs, as well as to low cost fabrication, RF applications, such as the LC-voltage controlled oscillator (LC-VCO), are usually implemented in CMOS technology. The complexity of designing LC-VCOs has lead to the development of several design methodologies. This chapter introduces an optimization based methodology for the design of LC-VCOs, where its efficiency is granted by the use of analytical models to characterize the active and passive elements’ behaviour.

Structural Basis for Host Membrane Remodeling Induced by Protein 2B of Hepatitis A Virus

Journal of virology, Jan 14, 2015

The complexity of viral RNA synthesis and the numerous participating factors require a mechanism ... more The complexity of viral RNA synthesis and the numerous participating factors require a mechanism to topologically coordinate and concentrate these multiple viral and cellular components, ensuring a concerted function. Similar to all other positive-strand RNA viruses, picornaviruses induce rearrangements of host intracellular membranes to create structures, which act as functional scaffolds for genome replication. The membrane-targeting proteins 2B, 2C, their precursor 2BC, and protein 3A appear primarily involved in membrane remodeling. Little is known about the structure of these proteins and the mechanisms by which they induce massive membrane remodeling. Here we report the crystal structure of the soluble region of hepatitis A virus (HAV) protein 2B, consisting of two domains: a C-terminal helical bundle, preceded by a N-terminal curved five-stranded anti-parallel β-sheet that displays striking structural similarity to the β-barrel domain of enteroviral 2A proteins. Moreover, the...

Effects of food restriction on synthesis and expression of brain-derived neurotrophic factor and tyrosine kinase B in dentate gyrus granule cells of adult rats

Neuroscience Letters, 2006

We have previously found that the dendritic trees of dentate gyrus granule cells are selectively ... more We have previously found that the dendritic trees of dentate gyrus granule cells are selectively vulnerable to food restriction but there are reorganizational morphological events that minimize functional impairments. As the neurotrophin brain-derived neurotrophic factor (BDNF) and the cognate receptor tyrosine kinase B (TrkB) are involved in the maintenance of the structure of dendritic trees, we thought of interest to

Spectrofluorimetric determination of formaldehyde in air after collection onto silica cartridges coated with Fluoral P

Microchemical Journal, 2004

The calibration curve obtained with concentrations of formaldehyde in the range of 12 to 192 ng m... more

[Comparative study of manual vacuum aspiration and uterine curettage for treatment of abortion]

Revista da Associação Médica Brasileira (1992)

To compare manual vacuum aspiration (MVA) and uterine curettage (D and C) for first trimester abo... more To compare manual vacuum aspiration (MVA) and uterine curettage (D and C) for first trimester abortions, in terms of the efficiency of eliminating ovular remnants, frequency of complications, duration of the procedure, and duration of patients' hospitalization. In a prospective study, 50 patients in the MVA group and 50 in the D&C group were randomly included. Inclusion criteria were: spontaneous abortion, gestational age less than 13 weeks, patent cervix, endometrial thickness >15 mm, afebrile state, and hemoglobin >10 g/dl. Blood samples were collected before and after surgical procedures for control of hemoglobin levels. Anesthesia was performed in all cases. The time required for each surgical procedure was recorded. Groups were similar regarding gestational age (9.93 +/- 2.40 vs 9.73 +/- 2.58 weeks; p = 0.71) and endometrial thickness before surgery (22.14 +/- 4.80 vs 22.68 +/- 5.68 mm; p = 0.65). There were no surgical or anesthetic complications in either group. Dur...

Fluorescent reporters for studies of cellular localization of proteins in Staphylococcus aureus

Applied and environmental microbiology, 2010

We have constructed a set of plasmids that allow expression, from their native chromosomal loci, ... more We have constructed a set of plasmids that allow expression, from their native chromosomal loci, of Staphylococcus aureus proteins fused to one of four different fluorescent proteins (green fluorescent protein [GFP], cyan fluorescent protein [CFP], yellow fluorescent protein [YFP], and mCherry), using two different resistance markers (kanamycin and erythromycin). We have also constructed a plasmid that allows expression of proteins from the ectopic spa locus in the S. aureus chromosome. This toolbox can be used for studies of the localization of proteins in S. aureus, a prominent pathogen in both health care and community settings.

Bacterial autolysins trim cell surface peptidoglycan to prevent detection by the Drosophila innate immune system

eLife, 2014

Bacteria have to avoid recognition by the host immune system in order to establish a successful i... more Bacteria have to avoid recognition by the host immune system in order to establish a successful infection. Peptidoglycan, the principal constituent of virtually all bacterial surfaces, is a specific molecular signature recognized by dedicated host receptors, present in animals and plants, which trigger an immune response. Here we report that autolysins from Gram-positive pathogenic bacteria, enzymes capable of hydrolyzing peptidoglycan, have a major role in concealing this inflammatory molecule from Drosophila peptidoglycan recognition proteins (PGRPs). We show that autolysins trim the outermost peptidoglycan fragments and that in their absence bacterial virulence is impaired, as PGRPs can directly recognize leftover peptidoglycan extending beyond the external layers of bacterial proteins and polysaccharides. The activity of autolysins is not restricted to the producer cells but can also alter the surface of neighboring bacteria, facilitating the survival of the entire population in...

The unique regulation of iron-sulfur cluster biogenesis in a Gram-positive bacterium

Proceedings of the National Academy of Sciences of the United States of America, Jan 3, 2014

Iron-sulfur clusters function as cofactors of a wide range of proteins, with diverse molecular ro... more Iron-sulfur clusters function as cofactors of a wide range of proteins, with diverse molecular roles in both prokaryotic and eukaryotic cells. Dedicated machineries assemble the clusters and deliver them to the final acceptor molecules in a tightly regulated process. In the prototypical Gram-negative bacterium Escherichia coli, the two existing iron-sulfur cluster assembly systems, iron-sulfur cluster (ISC) and sulfur assimilation (SUF) pathways, are closely interconnected. The ISC pathway regulator, IscR, is a transcription factor of the helix-turn-helix type that can coordinate a [2Fe-2S] cluster. Redox conditions and iron or sulfur availability modulate the ligation status of the labile IscR cluster, which in turn determines a switch in DNA sequence specificity of the regulator: cluster-containing IscR can bind to a family of gene promoters (type-1) whereas the clusterless form recognizes only a second group of sequences (type-2). However, iron-sulfur cluster biogenesis in Gram-p...

Characterization of binding epitopes of CA125 monoclonal antibodies

Journal of proteome research, Jan 3, 2014

The most used cancer serum biomarker is the CA125 immunoassay for ovarian cancer that detects the... more The most used cancer serum biomarker is the CA125 immunoassay for ovarian cancer that detects the mucin glycoprotein MUC16. Several monoclonal antibodies (mAbs) including OC125 and M11 are used in CA125 assays. However, despite considerable efforts, our knowledge of the molecular characteristics of the recognized epitopes and the role played by glycosylation has remained elusive. Here a comprehensive set of recombinant MUC16 tandem repeats (TRs) expressed in glycoengineered mammalian cells and E. coli, together with overlapping peptides, was used to probe antigen-binding epitopes. We present a complete analysis of N- and O-glycosylation sites of a MUC16 TR expressed in CHO cells and demonstrate that neither N- nor O-glycosylation appear to substantially influence binding of OC125 and M11 mAbs. A series of successive N- and C-terminal truncations of a MUC16 TR construct expressed in E. coli narrowed down the epitopes for OC125 and M11 to a segment containing parts of two consecutive ...

Carriage of Clostridium difficile in free-living South American coati (Nasua nasua) in Brazil

Anaerobe, 2014

The objective of this study was to isolate and characterize Clostridium difficile strains in stoo... more The objective of this study was to isolate and characterize Clostridium difficile strains in stool samples from a wild urban mammal, a South American coati (Nasua nasua) in Brazil. Forty-six free-living N. nasua were trapped, and stool samples were collected. C. difficile was isolated from three (6.5%) sampled animals, two strains were toxigenic (A+B+CDT-, PCR ribotype 014/020 and 106) and one was non toxigenic (A-B-CDT-, PCR ribotype 053). The present work confirms that ring-tailed coati (N. nasua) could harbor C. difficile strains, including those PCR ribotypes commonly reported in C. difficile infection in humans.

Pancreatic neuroendocrine tumour simulating an intraductal papillary mucinous neoplasm

Digestive and liver disease : official journal of the Italian Society of Gastroenterology and the Italian Association for the Study of the Liver, Jan 18, 2014