Research Interests:
Research Interests:
Research Interests:
Research Interests:
Recombinant Mycobacterium bovis bacille Calmette–Guèrin (rBCG) expressing three T cell epitopes of Mycobacterium tuberculosis (MTB) Ag85B antigen (P1, P2, P3) fused to the Mtb8.4 protein (rBCG018) or a combination of these antigens fused... more
Recombinant Mycobacterium bovis bacille Calmette–Guèrin (rBCG) expressing three T cell epitopes of Mycobacterium tuberculosis (MTB) Ag85B antigen (P1, P2, P3) fused to the Mtb8.4 protein (rBCG018) or a combination of these antigens fused to B cell epitopes from ESAT-6, CFP-10 and MTP40 proteins (rBCG032) were used to immunize Balb/c mice. Total IgG responses were determined against Mtb8.4 antigen and ESAT-6 and CFP-10 B cell epitopes after immunization with rBCG032. Mice immunized with rBCG032 showed a significant increase in IgG1 and IgG2a antibodies against ESAT-6 and MTP40 (P1) B cell epitopes and IgG3 against both P1 and P2 B cell epitopes of MPT40. Splenocytes from mice immunized with rBCG018 proliferated against Ag85B P2 and P3 T cell epitopes and Mtb8.4 protein whereas those from mice-immunized with rBCG032 responded against all Ag85B epitopes and the ESAT-6 B cell epitope. CD4+ and CD8+ lymphocytes from mice immunized with rBCG018 produced primarily Th1 type cytokines in res...
Research Interests:
Mycobacterium massiliense is an environmental opportunistic pathogen that has been associated with soft tissue infection after minor surgery. We studied the acute immune response of C57BL/6 and BALB/c mice infected intravenously with 10 6... more
Mycobacterium massiliense is an environmental opportunistic pathogen that has been associated with soft tissue infection after minor surgery. We studied the acute immune response of C57BL/6 and BALB/c mice infected intravenously with 10 6 CFU of an M. massiliense strain isolated from a nosocomial infection in Brazil. The results presented here show that M. massiliense is virulent and pathogenic to both C57BL/6 and BALB/c mice, inducing a granulomatous inflammatory reaction that involves the activation of macrophages, dendritic cells, and natural killer cells induced by gamma interferon and interleukin-17 (IL-17) in C57BL/6 mice and by IL-12 in BALB/c mice.
Research Interests:
complex has been characterized in the last decade as part of a cluster of mycobacteria that evolved from an opportunistic to true human pathogen; however, the factors responsible for pathogenicity are still undefined. It appears that the... more
complex has been characterized in the last decade as part of a cluster of mycobacteria that evolved from an opportunistic to true human pathogen; however, the factors responsible for pathogenicity are still undefined. It appears that the success of mycobacterial infection is intrinsically related with the capacity of the bacteria to regulate intracellular iron levels, mostly using iron storage proteins. This study evaluated two potential subsp. genes involved in iron storage. Unlike other opportunist or pathogenic mycobacteria studied, complex has two genes similar to ferritins from (Rv3841), and in subsp. , those genes are annotated as and . Molecular dynamic analysis of the predicted expressed proteins showed that they have a ferroxidase center. The expressions of and genes were modulated by the iron levels in both cultures as well as infected macrophages. Structural studies using size-exclusion chromatography, circular dichroism spectroscopy and dynamic light scattering showed th...
Mycobacterium tuberculosis is one of the most prevalent human pathogens causing millions of deaths in the last years. Moreover, tuberculosis (TB) treatment has become increasingly challenging owing to the emergence of multidrug resistant... more
Mycobacterium tuberculosis is one of the most prevalent human pathogens causing millions of deaths in the last years. Moreover, tuberculosis (TB) treatment has become increasingly challenging owing to the emergence of multidrug resistant M. tuberculosis strains. Thus, there is an immediate need for the development of new anti-TB drugs. Proteases appear to be a promising approach and may lead to shortened and effective treatments for drug-resistant TB. Although the M. tuberculosis genome predicts more than 100 genes encoding proteases, only a few of them have been studied. Aminopeptidases constitute a set of proteases that selectively remove amino acids from the N-terminus of proteins and peptides and may act as virulence factors, essential for survival and maintenance of many microbial pathogens. Here, we characterized a leucine aminopeptidase of M. tuberculosis (MtLAP) as a cytosolic oligomeric metallo-aminopeptidase. Molecular and enzymatic properties lead us to classify MtLAP as ...
Research Interests:
The present study aimed to assess the CD4, CD8 and γδ blood levels for Curraleiro Pé-duro, as well as the specific IFN-γ response after BCG vaccination using flow cytometry. The specific immune response against BCG was also evaluated by... more
The present study aimed to assess the CD4, CD8 and γδ blood levels for Curraleiro Pé-duro, as well as the specific IFN-γ response after BCG vaccination using flow cytometry. The specific immune response against BCG was also evaluated by tuberculin skin test, performed before and 45 days after the vaccination. For comparison purposes, the same parameters were investigated on Nellore calves, an exotic bovine with resistance previously demonstrated. Naturally, Curraleiro Pé-duro animals had greater levels of CD4, CD8 and γδ lymphocytes (p<0.05). In response to vaccine, Curraleiro Pé-duro showed greater ability to respond specifically to BCG, generating resistance profile (Th1), evidenced by greater number of antigen specific CD4+ cells producing IFN-γ (p<0.05) and also higher tuberculin skin test reaction (p<0.05). Additionally, vaccinated Curraleiro Pé-duro calves had higher CD4 cells numbers than both Nellore control (p<0.05) and vaccinated groups (p<0.05). Curraleiro ...
Research Interests:
Research Interests:
Multi-drug resistant microorganisms have been a growing concern during the last decades due to their contribution in mortality rates worldwide. Antimicrobial peptides (AMPs) are broad spectrum antimicrobial agents that display potent... more
Multi-drug resistant microorganisms have been a growing concern during the last decades due to their contribution in mortality rates worldwide. Antimicrobial peptides (AMPs) are broad spectrum antimicrobial agents that display potent microbicidal activity against a wide range of microorganisms. AMPs generally have a rapid mode of action that reduces the risk of resistance developing among pathogens. In this study, an AMP derived from scorpion venom, NDBP-5.5, was evaluated against Mycobacterium abscessus subsp. massiliense, a rapidly growing and emerging pathogen associated with healthcare infections. The minimal bactericidal concentration of NDBP-5.5, AMP quantity necessary to stop bacteria visible growth, against M. abscessus subsp. massiliense was 200 μM, a concentration that did not induce hemolysis of human red blood cells. The therapeutic index was 3.05 indicating a drug with low toxicity and therefore good clinical potential. Treatment of infected macrophages with NDBP-5.5 or...
Research Interests:
Tuberculosis is a contagious infectious disease caused by Mycobacterium tuberculosis, an obligate intracellular bacterium that relies on infection and host to host transmission to survive. In a co-evolution process, the pathogen developed... more
Tuberculosis is a contagious infectious disease caused by Mycobacterium tuberculosis, an obligate intracellular bacterium that relies on infection and host to host transmission to survive. In a co-evolution process, the pathogen developed virulence mechanisms to evade the host’s immune system and endure many factors, such as cellular stress for example. One of the strategies used by pathogens to achieve success in their infection is the production of proteases, which are enzymes that cleave peptide bonds between the amino acids in a protein. Proteases are widely distributed in the nature and have different roles that are considered important to the bacteria biological cycle. M. tuberculosis have several protease coding genes in its genome, many of which with unknown function, but several with attributed role in the infection process. This review presents the literature searched between 2014 and 2018 that addressed the roles of the proteases involved in the Mycobacterium tuberculosis...
Research Interests:
Research Interests:
Mycobacterium bovis Bacillus Calmette-Guérin (BCG) is a vaccine used to prevent tuberculosis (TB). Due to the poor protection conferred by BCG in adults, new, more effective formulations have been developed. A recombinant BCG vaccine... more
Mycobacterium bovis Bacillus Calmette-Guérin (BCG) is a vaccine used to prevent tuberculosis (TB). Due to the poor protection conferred by BCG in adults, new, more effective formulations have been developed. A recombinant BCG vaccine expressing the CMX fusion protein Ag85c_MPT51_HspX (rBCG-CMX) induced Th1 and Th17 responses and provided better protection than BCG. It has been shown that Mycobacterium smegmatis expressing CMX also induces better protection than BCG and is a strong macrophage activator. The aim of the present study was to evaluate macrophage activation by the recombinant CMX fusion protein and by rBCG-CMX and to evaluate their ability to generate vaccine-specific immune responses. The results demonstrate that rCMX protein expressed by BCG (rBCG-CMX) activates pulmonary macrophages; increases the expression of activation molecules, cytokines, and MHC-II. The interaction with rCMX activates the transcription factor NF-κB and induces the production of the cytokines TGF-...
Noroviruses (NoVs) are an important cause of acute gastroenteritis (AGE), worldwide. To evaluate the frequency, viral load and molecular profile of NoV in fecal and nasopharyngeal swab samples from hospitalized children, and to determine... more
Noroviruses (NoVs) are an important cause of acute gastroenteritis (AGE), worldwide. To evaluate the frequency, viral load and molecular profile of NoV in fecal and nasopharyngeal swab samples from hospitalized children, and to determine children&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s secretor status. From May 2014 to May 2015, 219 children were included in the study, 96 with gastroenteric symptoms and 123 without gastroenteric symptoms. All fecal and nasopharyngeal swab samples were screened by TaqMan RT-qPCR duplex (GI/GII NoV) and quality samples were characterized by genomic sequencing. Norovirus positivity rate in feces was 15.4% in asymptomatic and 18.8% in the symptomatic group. The median viral loads in feces were 2.69×10(8)GC/g and 4.32×10(7)GC/g from children with or without AGE symptoms, respectively. In nasopharyngeal swab samples, the NoV positivity was 11.4% in symptomatic children, with a median viral load of 2.20×10(7)GC/mL and 6.5% in asymptomatic children, with an average viral load of 1.73×10(6)GC/mL. In only two cases NoV was detected in both samples. A considerable genomic variability was observed in feces, with six genotypes being detected, as follows: GII.4, GII.6, GI.3 and GII.3, GI.2 and GI.5. Two GI.3 was detected in nasopharyngeal swab. Our data reveal considerable NoV frequencies in both nasopharyngeal and fecal samples from symptomatic and asymptomatic children. Higher viral loads were detected in samples from AGE symptomatic children, when compared to asymptomatic children. High genomic variability was observed, with this being the first report of GI.5 NoV in Brazil and of GI.3 in nasopharyngeal swab samples.
Research Interests: Microbiology, Medical Microbiology, Brazil, Clinical Virology, Humans, and 15 moreChild, Norovirus, Female, Male, Infant, Clinical Sciences, Newborn Infant, Prevalence, Genotype, Feces, Cross Sectional Studies, Viral Load, Child preschool, reverse transcriptase polymerase chain reaction, and Nasopharynx
Mastoparans, a class of peptides found in wasp venom, have significant effects following a sting as well as useful applications in clinical practice. Among these is their potential use in the control of micro-organisms that cause... more
Mastoparans, a class of peptides found in wasp venom, have significant effects following a sting as well as useful applications in clinical practice. Among these is their potential use in the control of micro-organisms that cause infectious diseases with a significant impact on society. Thus, the present study describes the isolation and identification of a mastoparan peptide from the venom of the social wasp Pseudopolybia vespiceps and evaluated its antimicrobial profile against bacteria (Staphylococcus aureus and Mycobacterium abscessus subsp. massiliense), fungi (Candida albicans and Cryptococcus neoformans) and in vivo S. aureus infection. The membrane pore-forming ability was also assessed. The mastoparan reduced in vitro and ex vivo mycobacterial growth by 80% at 12.5 µM in infected peritoneal macrophages but did not affect the shape of bacterial cells at the dose tested (6.25 µM). The peptide also showed potent action against S. aureus in vitro (EC50 and EC90 values of 1.83 µ...
Research Interests:
Research Interests:
Research Interests:
Research Interests:
... para imprimir. Fotocópia. André, Maria Cláudia DP Borges. experimental, Documentos relacionados. Id: 346063. Autor: Rodrigues, Márcia Alves Vasconcelos; André, Maria Cláudia DP Borges; Alves, Suely Lemes de; Souza, Marieta Pereira M;... more
... para imprimir. Fotocópia. André, Maria Cláudia DP Borges. experimental, Documentos relacionados. Id: 346063. Autor: Rodrigues, Márcia Alves Vasconcelos; André, Maria Cláudia DP Borges; Alves, Suely Lemes de; Souza, Marieta Pereira M; Kipnis, André; Serafini, Alvaro ...
Research Interests:
Although the attenuated Mycobacterium bovis Bacillus Calmette-Guérin (BCG) vaccine has been used since 1921, tuberculosis (TB) control still proceeds at a slow pace. The main reason is the variable efficacy of BCG protection against TB... more
Although the attenuated Mycobacterium bovis Bacillus Calmette-Guérin (BCG) vaccine has been used since 1921, tuberculosis (TB) control still proceeds at a slow pace. The main reason is the variable efficacy of BCG protection against TB among adults, which ranges from 0-80%. Subsequently, the mc2-CMX vaccine was developed with promising results. Nonetheless, this recombinant vaccine needs to be compared to the standard BCG vaccine. The objective of this study was to evaluate the immune response induced by mc2-CMX and compare it to the response generated by BCG. BALB/c mice were immunised with both vaccines and challenged withMycobacterium tuberculosis (Mtb). The immune and inflammatory responses were evaluated by ELISA, flow cytometry, and histopathology. Mice vaccinated with mc2-CMX and challenged with Mtb induced an increase in the IgG1 and IgG2 levels against CMX as well as recalled specific CD4+ T-cells that produced T-helper 1 cytokines in the lungs and spleen compared with BCG ...
Research Interests:
Mycobacterium abscessus subsp. massiliense, a rapidly growing mycobacteria (RGM) that is becoming increasingly important among human infectious diseases, is virulent and pathogenic and presents intrinsic resistance to several... more
Mycobacterium abscessus subsp. massiliense, a rapidly growing mycobacteria (RGM) that is becoming increasingly important among human infectious diseases, is virulent and pathogenic and presents intrinsic resistance to several antimicrobial drugs that might hamper their elimination. Therefore, the identification of new drugs to improve the current treatment or lower the risk of inducing resistance is urgently needed. Wasp venom primarily comprises peptides that are responsible for most of the biological activities in this poison. Here, a novel peptide Polydim-I, from Polybia dimorpha Neotropical wasp, was explored as an antimycobacterial agent. Polydim-I provoked cell wall disruption and exhibited non-cytotoxicity towards mammalian cells. Polydim-I treatment of macrophages infected with different M. abscessus subsp. massiliense strains reduced 40 to 50% of the bacterial load. Additionally, the Polydim-I treatment of highly susceptible mice intravenously infected with M. abscessus sub...
Research Interests: Scanning Electron Microscopy, Scanning Transmission Electron Microscopy, Macrophages, Multidisciplinary, Cell line, and 13 moreWasps, Mycobacterium, Female, Animals, Peptides, PLoS one, High Pressure Liquid Chromatography, Anti-Bacterial Agents, Microbial Sensitivity Tests, Host Pathogen Interactions, Amino Acid Sequence, Interferon gamma, and Molecular Sequence Data
Kipnis, André; Crespo, Adriana de Moraes Costa; Oliveira, Flávia Aparecida de; Silva, Heloisa Helena Garcia da; Souza, Keili Maria Cardoso de; Silveira, Lucimeire Antonelli da; Alves, Maria de Fátima Costa; Silva, Maria do Rosário... more
Kipnis, André; Crespo, Adriana de Moraes Costa; Oliveira, Flávia Aparecida de; Silva, Heloisa Helena Garcia da; Souza, Keili Maria Cardoso de; Silveira, Lucimeire Antonelli da; Alves, Maria de Fátima Costa; Silva, Maria do Rosário Rodrigues; Martins, Regina Maria Bringel; Brito, ...
The effect of carbon sources on the level of beta-1,3-glucanases in the culture filtrates of Trichoderma harzianum (Tc) was investigated. Enzyme activity was detected in all carbon sources, but highest levels were found when laminarin and... more
The effect of carbon sources on the level of beta-1,3-glucanases in the culture filtrates of Trichoderma harzianum (Tc) was investigated. Enzyme activity was detected in all carbon sources, but highest levels were found when laminarin and purified cell walls were used. Three isoforms of beta-1,3-glucanase were produced during growth of the fungus on purified cell walls. Two isoforms were produced on chitin, chitosan, N-acetylglucosamine and laminarin, while only one was detected when the fungus was grown on cellulose and glucose. A 36-kDa beta-1,3-glucanase (GLU36) was secreted from T. harzianum (Tc) grown on all carbon sources tested as demonstrated by Western blot analysis. We found that a significant increase in the level of GLU36 in the culture filtrate follows glucose exhaustion, suggesting that this enzyme is controlled by carbon catabolite repression.
Research Interests:
Research Interests:
Background: Multi (MDR) and extensively (XDR) drug resistant strains of Mycobacterium tuberculosis threatens the global control of tuberculosis, since their treatment are complex and expensive with higher rates of failures and side... more
Background: Multi (MDR) and extensively (XDR) drug resistant strains of Mycobacterium tuberculosis threatens the global control of tuberculosis, since their treatment are complex and expensive with higher rates of failures and side effects. The genotyping of M. tuberculosis is important for understanding of multi-drug resistance strains fitness after drug resistance acquisition and of the transmission dynamics of these strains in a particular region. The objectives were to describe the clinical and restriction fragment lenght polymorphism (RFLP) profiles of MDR and XDR M. tuberculosis strains from patients of tertiary hospital in Goias, a central State in Brazil, a region with low incidence of drug resistance. Methods: The clinical charts were reviewed in order to collect the patients’ clinical data. Samples were processed by culture in Lowenstein-Jensen (L-J) for DNA extraction and IS6110-RFLP typing. The IS6110-RFLP patterns were introduced into the Bionumerics software (Windows v...
Research Interests:
Coagulase-negative staphylococci are frequently associated with nosocomial infections, and healthcare professionals can be reservoirs and spread them in hospitals and in the community. The aim of this study was to identify species of... more
Coagulase-negative staphylococci are frequently associated with nosocomial infections, and healthcare professionals can be reservoirs and spread them in hospitals and in the community. The aim of this study was to identify species of coagulase-negative staphylococci isolated from the saliva of nursing professionals, determine the resistance profile and detect the mecA gene. One hundred coagulase-negative staphylococci were selected: 41 were identified as Staphylococcus epidermidis, 25 as Staphylococcus saprophyticus, 18 as Staphylococcus haemolyticus, eight as Staphylococcus cohnii, four as Staphylococcus lugdunenses, three as Staphylococcus capitis and one as Staphylococcus simulans. Of these, 32% presented oxacillin resistance, 84.4% mupirocin resistance and 32% cefoxitin resistance, and all were vancomycin sensitive. Among the oxacillin-resistant coagulase-negative staphylococci, 93.7% developed in oxacillin agar (6microg/ml) and the mecA gene was detected in 75%. The results ind...
Research Interests:
Research Interests:
Research Interests: Brazil, Medicine, Case Report, Humans, Mycobacterium tuberculosis, and 5 moreFemale, Male, Young Adult, Adult, and Brazilian
Research Interests:
Virulence factors represent crucial molecular features for understanding pathogenic mechanisms. Here we describe a pipeline for in silico prediction of virulence factor genes in Mycobacterium massiliense genome that could be easily used... more
Virulence factors represent crucial molecular features for understanding pathogenic mechanisms. Here we describe a pipeline for in silico prediction of virulence factor genes in Mycobacterium massiliense genome that could be easily used in many other bacterial systems. Some few methods for this characterization are described in the literature, however these approaches are usually time-consuming and require information not always readily available. Using the proposed pipeline, the number and the accuracy of predicted ORF annotation were increased, and a broad identification of virulence factors could be achieved. Based on these results, we were able to construct a general pathogenic profile of M. massiliense. Furthermore, two important metabolic pathways, production of siderophores and bacterial secretion systems, both related to M. massiliense's pathogenicity, were investigated.
Research Interests:
Este trabalho objetivou caracterizar fenotipicamente isolados de Escherichia coli a partir de amostras obtidas de mãos e narizes de manipuladores, de leite cru e de queijo Minas Frescal produzidos em um laticínio em Goiás, Brasil, visando... more
Este trabalho objetivou caracterizar fenotipicamente isolados de Escherichia coli a partir de amostras obtidas de mãos e narizes de manipuladores, de leite cru e de queijo Minas Frescal produzidos em um laticínio em Goiás, Brasil, visando a estabelecer uma relação de contaminação entre o manipulador e/ou a matéria-prima e o produto final. Foram coletadas 24 amostras de leite cru e de queijo Minas Frescal, 46 swabs de mãos e 46 de narizes dos manipuladores envolvidos na fabricação do queijo, no período entre março/2004 e fevereiro/2005. As 69 cepas isoladas foram submetidas ao teste de suscetibilidade a seis antimicrobianos (ampicilina, cefalotina, ciprofloxacina, gentamicina, sulfametoxazol trimetoprin e tetraciclina) e, a partir deste teste, foi possível agrupá-las em 17 diferentes perfis fenotípicos (A-Q). Somente um perfil fenotípico (E) foi semelhante entre cepas de E. coli isoladas, tanto de amostra de queijo (14Qb) como de um dos manipuladores (10M1). Tal resultado sugere uma ...
Research Interests:
Multi-drug resistant pulmonary tuberculosis (MDR-TB) may result from either insufficiency of the host cellular immune response or mycobacterial mechanisms of resistance. Mycobacterium tuberculosis-specific CD8+ and CD4+ T lymphocytes from... more
Multi-drug resistant pulmonary tuberculosis (MDR-TB) may result from either insufficiency of the host cellular immune response or mycobacterial mechanisms of resistance. Mycobacterium tuberculosis-specific CD8+ and CD4+ T lymphocytes from MDR-TB patients are poorly studied. The aim of this study was to evaluate CD4+IFN-gamma+, CD4+IL-10+, CD8(+)IFN-gamma+ and CD8+IL-10+ cell populations by flow cytometry in non-resistant TB and multi-drug resistant tuberculosis (MDR-TB) patients from mid-central Brazil after stimulation with MPT-51, GlcB and ESAT-6 recombinant antigens from M. tuberculosis in comparison to tuberculin skin test negative (TST) healthy individuals. Non-resistant TB patients present specific cellular responses (CD4 and CD8, both IFN-gamma and IL-10) to GlcB, MPT-51 and ESAT-6; while MDR-TB patients present only CD8+IFN-gamma+ responses to ESAT-6 and CD8+IL-10+ responses to GlcB and ESAT-6. The results show that MDR-TB patients present impaired specific CD4 IFN-gamma and IL-10 responses and increased/normal specific CD8 IFN-gamma and IL-10 responses. This suggests an important role for CD8 function in these patients.
Research Interests:
OBJETIVO: Determinar a prevalência de microrganismos indicadores e potencialmente patogênicos que indicam as condições higiênico-sanitárias das amostras de leite humano ordenhado coletadas em banco de leite. MÉTODOS: Foram realizadas... more
OBJETIVO: Determinar a prevalência de microrganismos indicadores e potencialmente patogênicos que indicam as condições higiênico-sanitárias das amostras de leite humano ordenhado coletadas em banco de leite. MÉTODOS: Foram realizadas análises microbiológicas de 338 amostras de leite humano ordenhado, sendo 194 de leite cru e 144, pasteurizado, coletadas em banco de leite humano de um hospital materno infantil de Goiânia, GO. As análises microbiológicas foram realizadas com semeadura em ágar Mc Conkey, de acordo com o tipo de bactéria. RESULTADOS: No leite cru, verificou-se a presença de Staphylococcus spp. Streptococcus spp., bolores e leveduras e Enterobacteriaceae. Observou-se que Staphylococcus aureus esteve presente em 10 (5,2%) amostras, Staphylococcus epidermidis em 28 (14,4%), Streptococcus spp. em três (1,6%), bolores e leveduras em 43 (22,2%) e Enterobacteriaceae em 49 (25,3%). Das 144 amostras de leite humano ordenhado pasteurizado, detectaram-se Staphylococcus aureus em c...
Research Interests:
Research Interests:
[This corrects the article on p. e47781 in vol. 7.].
Research Interests:
Research Interests:
Research Interests:
Investigations regarding Staphylococcus aureus carriage among Brazilian children are scarce. We evaluated the determinants of S. aureus and methicillin-resistant S. aureus (MRSA) nasal carriage in infants attending day care centers (DCCs)... more
Investigations regarding Staphylococcus aureus carriage among Brazilian children are scarce. We evaluated the determinants of S. aureus and methicillin-resistant S. aureus (MRSA) nasal carriage in infants attending day care centers (DCCs) and the molecular features of the MRSA strains. A total of 1,192 children aged 2 months to 5 years attending 62 DCCs were screened for S. aureus and MRSA nasal carriage. MRSA isolates were characterized by pulsed-field gel electrophoresis, multilocus sequence typing, spa typing, staphylococcal cassette chromosome (SCC) mec typing and the presence of the Panton-Valentine leukocidin gene. Logistic regression was performed to determine risk factors associated with S. aureus and MRSA colonization. S. aureus and MRSA carriage were detected in 371 (31.1%) and 14 (1.2%) children, respectively. Variables found to be independently associated with an increased risk for S. aureus carriage included being older than 24 months (odds ratio [OR], 1.8; 95% confiden...
Research Interests: Microbiology, Brazil, Molecular Epidemiology, Clinical Microbiology, Biological Sciences, and 15 moreHumans, Female, Clinical, Male, Bacteria, Infant, Risk Factor, Genotype, Risk Factors, Nose, Cross Sectional Studies, Methicillin Resistant Staphylococcus Aureus, Child preschool, Carrier state, and Medical and Health Sciences
The biodiversity of entomopathogenic fungi in tropical ecosystems is still little investigated, and the objective of this study was to isolate and identify fungi of the entomopathogenic genus Metarhizium (Hypocreales: Clavicipitaceae)... more
The biodiversity of entomopathogenic fungi in tropical ecosystems is still little investigated, and the objective of this study was to isolate and identify fungi of the entomopathogenic genus Metarhizium (Hypocreales: Clavicipitaceae) present in undisturbed soils of the Central Brazilian Cerrado. A total of 107 Metarhizium isolates was obtained from soils collected from Cerrado sites in the state of Goiás; gene sequences from 63 of these were obtained and compared. Among these, one was confirmed to be M. anisopliae sensu stricto; 53 were very closely allied to M. anisopliae but require more extensive genetic characterization to determine if they might represent a new taxon in the M. anisopliae species complex. Eight of these Cerrado isolates were referable to M. robertsii, and the remaining isolate is the first South American (and Southern Hemisphere) collection of M. flavoviride var. pemphigi. These findings underline the need for better characterization of the diversity of these widely distributed fungi in Brazil.
Research Interests:
Research Interests:
Haemophilus influenzae type b vaccine was introduced into the Immunization Program of Brazil in 1999 and no study has evaluated the impact of Hib vaccination in H. influenzae carriage so far. In June 2010, Brazil introduced the 10-valent... more
Haemophilus influenzae type b vaccine was introduced into the Immunization Program of Brazil in 1999 and no study has evaluated the impact of Hib vaccination in H. influenzae carriage so far. In June 2010, Brazil introduced the 10-valent pneumococcal nontypeable H. influenzae (NTHi) conjugate vaccine (PHiD-CV). We investigated the prevalence of encapsulated H. influenzae and NTHi isolates in nasopharyngeal samples of 1192 children attending day-care centers in Goiânia, central Brazil. H. influenzae carriage rate was 32.1% and 38.4% of them carried β-lactamase TEM-1 gene. Serotype f (4.6%) was the most frequent encapsulated isolate, type b was recovered in only 0.7% and carriage rate of NTHi was 23.3%. Recurrent acute otitis media and NTHi were independently associated with colonization by β-lactamase producing H. influenzae. Changes in frequency of H. influenzae carriage isolates should be carefully monitored to assess the impact of the PHiD-CV on NTHi carriage in young children.
Research Interests:
Our aim is to investigate if the clusters of postsurgical mycobacterial infections, reported between 2004 and 2008 in seven geographically distant states in Brazil, were caused by a single mycobacterial strain. Available information from... more
Our aim is to investigate if the clusters of postsurgical mycobacterial infections, reported between 2004 and 2008 in seven geographically distant states in Brazil, were caused by a single mycobacterial strain. Available information from 929 surgical patients was obtained from local health authorities. A total of 152 isolates from surgical patients were identified by PCR restriction enzyme analysis of the hsp65 gene (PRA-hsp65) and sequencing of the rpoB gene. Isolates were typed by pulsed-field gel electrophoresis (PFGE) using two restriction enzymes, DraI and AseI. A total of 15 isolates not related to surgical cases were analyzed for comparison. All isolates were identified as Mycobacterium abscessus ssp. massiliense. Isolates from surgical patients and one sputum isolate grouped in a single PFGE cluster, composed of two closely related patterns, with one band difference. A total of 14 other isolates unrelated to surgical cases showed distinctive PFGE patterns. A particular strain of M. abscessus ssp. massiliense was associated with a prolonged epidemic of postsurgical infections in seven Brazilian states, suggesting that this strain may be distributed in Brazilian territory and better adapted to cause surgical-site infections.