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Featured researches published by Guilherme Campos.


BMC Infectious Diseases | 2015

Prevalence of Mycoplasma genitalium and Mycoplasma hominis in urogenital tract of Brazilian women

Guilherme Campos; Tássia Neves Lobão; Nathan das Neves Selis; Aline T. Amorim; Hellen Braga Martins; Maysa Santos Barbosa; Thiago Henrique Caldeira de Oliveira; Djanilson Barbosa dos Santos; Tiana Baqueiro Figueiredo; Lucas Miranda Marques; Jorge Timenetsky

BackgroundThe role of Mycoplasma hominis and M. genitalium in urogenital tract infections remains unknown. Furthermore these mollicutes present a complex relationship with the host immune response. The role of inflammatory cytokines in infections also makes them good candidates to investigate bacterial vaginosis and mycoplasma genital infections. Therefore, the aim of this study was to detect the above-mentioned mollicutes by quantitative Polymerase Chain Reaction (qPCR) methodologies in vaginal swabs and dosage of cytokines.MethodsVaginal swabs and peripheral blood were collected from 302 women, including healthy individuals. The molecular findings were correlated with some individual behavioral variables, clinical and demographic characteristics, presence of other important microorganisms in vaginal swabs, and levels of interleukin (IL)-1β and IL-6.ResultsM. hominis and M. genitalium were detected in 31.8% and 28.1% of samples, respectively. The qPCR results were associated with clinical signs and symptoms of the infections studied. The frequency of Trichomonas vaginalis, Gardnerella vaginalis, Neisseria gonorrhoeae and Chlamydia trachomatis was 3.0%, 21.5%, 42.4%, and 1.7% respectively. Increased levels of IL-1β were associated with the presence of M. hominis and signs and/or symptoms of the genital infection of women studied.ConclusionIL-1β production was associated with the detection of M. hominis by qPCR. The sexual behavior of women studied was associated with the detection of mycoplasma and other agents of genital infections.


PLOS ONE | 2013

Learning auditory space: Generalization and Long-Term Effects

Catarina Mendonça; Guilherme Campos; Paulo Dias; Jorge A. Santos

Background Previous findings have shown that humans can learn to localize with altered auditory space cues. Here we analyze such learning processes and their effects up to one month on both localization accuracy and sound externalization. Subjects were trained and retested, focusing on the effects of stimulus type in learning, stimulus type in localization, stimulus position, previous experience, externalization levels, and time. Method We trained listeners in azimuth and elevation discrimination in two experiments. Half participated in the azimuth experiment first and half in the elevation first. In each experiment, half were trained in speech sounds and half in white noise. Retests were performed at several time intervals: just after training and one hour, one day, one week and one month later. In a control condition, we tested the effect of systematic retesting over time with post-tests only after training and either one day, one week, or one month later. Results With training all participants lowered their localization errors. This benefit was still present one month after training. Participants were more accurate in the second training phase, revealing an effect of previous experience on a different task. Training with white noise led to better results than training with speech sounds. Moreover, the training benefit generalized to untrained stimulus-position pairs. Throughout the post-tests externalization levels increased. In the control condition the long-term localization improvement was not lower without additional contact with the trained sounds, but externalization levels were lower. Conclusion Our findings suggest that humans adapt easily to altered auditory space cues and that such adaptation spreads to untrained positions and sound types. We propose that such learning depends on all available cues, but each cue type might be learned and retrieved differently. The process of localization learning is global, not limited to stimulus-position pairs, and it differs from externalization processes.


Veterinary Microbiology | 2013

A quantitative TaqMan PCR assay for the detection of Ureaplasma diversum

Lucas M. Marques; Aline T. Amorim; Hellen Braga Martins; Izadora S. Rezende; Maysa Santos Barbosa; Tássia Neves Lobão; Guilherme Campos; Jorge Timenetsky

Ureaplasma diversum in veterinary studies is an undesirable microbe, which may cause infection in bulls and may result in seminal vesiculitis, balanopostitis, and alterations in spermatozoids, whereas in cows, it may cause placentitis, fetal alveolitis, abortion, and birth of weak calves. U. diversum is released through organic secretions, especially semen, preputial and vaginal mucus, conjunctival secretion, and milk. The aim of the present study was to develop a TaqMan probe, highly sensitive and specific quantitative PCR (qPCR) assay for the detection and quantification of U. diversum from genital swabs of bovines. Primers and probes specific to U. diversum 16S rRNA gene were designed. The specificity, detection limit, intra- and inter-assay variability of qPCR to detect this ureaplasma was compared with the results of the conventional PCR assay (cPCR). Swabs of vaginal mucus from 169 cows were tested. The qPCR assay detected as few as 10 copies of U. diversum and was 100-fold more sensitive than the cPCR. No cross-reactivity with other Mollicutes or eubacteria was observed. U. diversum was detected in 79 swabs (46.42%) by qPCR, while using cPCR it was detected in 42 (25%) samples. The difference in cPCR and qPCR ureaplasma detection between healthy and sick animals was not statistically significant. But the U. diversum load in samples from animals with genital disorders was higher than in healthy animals. The qPCR assay developed herein is highly sensitive and specific for the detection and quantification of U. diversum in vaginal bovine samples.


Brazilian Journal of Infectious Diseases | 2017

Community-acquired methicillin-resistant Staphylococcus aureus carrying SCCmec type IV and V isolated from healthy children attending public daycares in northeastern Brazil

Suzi P. de Carvalho; Jéssica Bomfim de Almeida; Yasmin M.F.S. Andrade; Lucas S.C. da Silva; Arianne C. de Oliveira; Flávia S. Nascimento; Guilherme Campos; Márcio Vasconcelos Oliveira; Jorge Timenetsky; Lucas M. Marques

Nasal colonization with methicillin-resistant Staphylococcus aureus (MRSA) have increasingly been reported in healthy communities. This study aimed to assess the rate of S. aureus in general and MRSA in particular from nasal secretion of children in daycare centers in Vitória da Conquista, Brazil. The isolates were identified based on morphology, biochemical tests and by PCR. Detection of virulence genes, biofilm production, and susceptibility test by disk diffusion agar were performed. MRSA isolates were characterized by spa, SCCmec, and multilocus sequence typing (MLST). S. aureus were recovered from 70 (47.3%) of 148 children. Among the 11 MRSA strains (15.7%), two SCCmec types (IV and V) were detected. MLST identified four STs related to three clonal complexes (CC): 5, 45, and 398. Four spa types were found circulating in this setting. Resistance of S. aureus isolates to ampicillin, erythromycin, ciprofloxacin, clindamycin, and tetracycline was 80%, 32.8%, 7.1%, 7.1% and 4.3%, respectively. One isolate presented intermediate resistance to vancomycin detected by Etest methodology. All strains were biofilm producers. The virulence genes seb, sec, spa, and pvl were detected in some isolates. This study revealed a high rate of children carrying MRSA among healthy attendees in daycare centers in Vitória da Conquista, Brazil.


PLOS ONE | 2016

Ureaplasma diversum Genome Provides New Insights about the Interaction of the Surface Molecules of This Bacterium with the Host

Lucas M. Marques; Izadora S. Rezende; Maysa Santos Barbosa; Ana M. S. Guimaraes; Hellen Braga Martins; Guilherme Campos; Naíla C. do Nascimento; Andrea Pires dos Santos; Aline T. Amorim; Verena M. Santos; Sávio Torres de Farias; Fernanda Â. C. Barrence; Lauro Mera de Souza; Melissa Buzinhani; Victor E. Arana-Chavez; Maria Emilia Zenteno; Gustavo P. Amarante-Mendes; Joanne B. Messick; Jorge Timenetsky

Whole genome sequencing and analyses of Ureaplasma diversum ATCC 49782 was undertaken as a step towards understanding U. diversum biology and pathogenicity. The complete genome showed 973,501 bp in a single circular chromosome, with 28.2% of G+C content. A total of 782 coding DNA sequences (CDSs), and 6 rRNA and 32 tRNA genes were predicted and annotated. The metabolic pathways are identical to other human ureaplasmas, including the production of ATP via hydrolysis of the urea. Genes related to pathogenicity, such as urease, phospholipase, hemolysin, and a Mycoplasma Ig binding protein (MIB)—Mycoplasma Ig protease (MIP) system were identified. More interestingly, a large number of genes (n = 40) encoding surface molecules were annotated in the genome (lipoproteins, multiple-banded antigen like protein, membrane nuclease lipoprotein and variable surface antigens lipoprotein). In addition, a gene encoding glycosyltransferase was also found. This enzyme has been associated with the production of capsule in mycoplasmas and ureaplasma. We then sought to detect the presence of a capsule in this organism. A polysaccharide capsule from 11 to 17 nm of U. diversum was observed trough electron microscopy and using specific dyes. This structure contained arabinose, xylose, mannose, galactose and glucose. In order to understand the inflammatory response against these surface molecules, we evaluated the response of murine macrophages J774 against viable and non-viable U. diversum. As with viable bacteria, non-viable bacteria were capable of promoting a significant inflammatory response by activation of Toll like receptor 2 (TLR2), indicating that surface molecules are important for the activation of inflammatory response. Furthermore, a cascade of genes related to the inflammasome pathway of macrophages was also up-regulated during infection with viable organisms when compared to non-infected cells. In conclusion, U. diversum has a typical ureaplasma genome and metabolism, and its surface molecules, including the identified capsular material, represent major components of the organism immunopathogenesis.


Epidemiology and Infection | 2017

Ureaplasma urealyticum and U. parvum in sexually active women attending public health clinics in Brazil

Tássia Neves Lobão; Guilherme Campos; Nathan das Neves Selis; Aline T. Amorim; S. G. Souza; S. S. Mafra; L. S. Pereira; D. B. Dos Santos; Tiana Baqueiro Figueiredo; Lucas Miranda Marques; Jorge Timenetsky

Ureaplasma urealyticum and U. parvum have been associated with genital infections. The purpose of this study was to detect the presence of ureaplasmas and other sexually transmitted infections in sexually active women from Brazil and relate these data to demographic and sexual health, and cytokines IL-6 and IL-1β. Samples of cervical swab of 302 women were examined at the Family Health Units in Vitória da Conquista. The frequency of detection by conventional PCR was 76·2% for Mollicutes. In qPCR, the frequency found was 16·6% for U. urealyticum and 60·6% U. parvum and the bacterial load of these microorganisms was not significantly associated with signs and symptoms of genital infection. The frequency found for Trichomonas vaginalis, Neisseria gonorrhoeae, Gardnerella vaginalis and Chlamydia trachomatis was 3·0%, 21·5%, 42·4% and 1·7%, respectively. Higher levels of IL-1β were associated with control women colonized by U. urealyticum and U. parvum. Increased levels of IL-6 were associated with women who exhibited U. parvum. Sexually active women, with more than one sexual partner in the last 3 months, living in a rural area were associated with increased odds of certain U. parvum serovar infection.


biomedical engineering systems and technologies | 2015

On the Validation of Computerised Lung Auscultation

Guilherme Campos; João Quintas

The development of computerised diagnosis tools based on lung auscultation necessitates appropriate validation. So far, this work front has received insufficient attention from researchers; validation studies found in the literature are largely flawed. We believe that building open-access crowd-sourced information systems based on large-scale repositories of respiratory sound files is an essential task and should be urgently addressed. Most diagnosis tools are based on automatic adventitious lung sound (ALS) detection algorithms. The gold standards required to assess their performance can only be obtained by human expert annotation of a statistically significant set of respiratory sound files; given the inevitable subjectivity of the process, statistical agreement criteria must be applied to multiple independent annotations obtained for each file. For these reasons, the information systems we propose should provide simple, efficient annotation tools; facilitate the formation of credible annotation panels; apply appropriate agreement criteria and metrics to generate goldstandard ALS annotation files and, based on them, allow easy quantitative assessment of detection algorithm performance.


Genome Announcements | 2015

Genome Sequence of Ureaplasma diversum Strain ATCC 49782.

Lucas M. Marques; Ana M. S. Guimaraes; Hellen Braga Martins; Izadora S. Rezende; Maysa Santos Barbosa; Guilherme Campos; Naíla C. do Nascimento; Andrea Pires dos Santos; Aline T. Amorim; Verena M. Santos; Joanne B. Messick; Jorge Timenetsky

ABSTRACT Here, we report the complete genome sequence of Ureaplasma diversum strain ATCC 49782. This species is of bovine origin, having an association with reproductive disorders in cattle, including placentitis, fetal alveolitis, abortion, and birth of weak calves. It has a small circular chromosome of 975,425 bp.


Frontiers in Microbiology | 2018

Ureaplasma diversum and Its Membrane-Associated Lipoproteins Activate Inflammatory Genes Through the NF-κB Pathway via Toll-Like Receptor 4

Manoel N. Santos-Junior; Izadora S. Rezende; Clarissa Leal Silva e Souza; Maysa S. Barbosa; Guilherme Campos; Laís F. Brito; Éllunny C. Queiroz; Elaine N. Barbosa; Mariana M. Teixeira; Letícia O. Da Silva; Lucas S.C. da Silva; Flávia S. Nascimento; Tassyo L. Da Silva; Adam Martens; Adriano Felipe Perez Siqueira; Mayra Elena Ortiz D'Avila Assumpção; Gláucia Maria Machado-Santelli; Bruno Lopes Bastos; Ana M. S. Guimaraes; Jorge Timenetsky; Lucas M. Marques

Objectives: Ureaplasma diversum is a pathogen of cows that may cause intense inflammatory responses in the reproductive tract and interfere with bovine reproduction. The aims of this study were to evaluate the immune response of bovine blastocysts and macrophages to U. diversum infection and to evaluate the invasion capacity of this microorganism in bovine blastocysts. Methods: Viable and heat-inactivated U. diversum strains ATCC 49782 and CI-GOTA and their extracted membrane lipoproteins were inoculated in macrophages in the presence or absence of signaling blockers of Toll-Like Receptor (TLR) 4, TLR2/4, and Nuclear Factor KB (NF-κB). In addition, the same viable U. diversum strains were used to infect bovine blastocysts. RNA was extracted from infected and lipoprotein-exposed macrophages and infected blastocysts and assayed by qPCR to evaluate the expression of Interleukin 1 beta (IL-1β), Tumor Necrosis Factor Alpha (TNF-α), TLR2 and TLR4 genes. U. diversum internalization in blastocysts was followed by confocal microscopy. Results: Both Ureaplasma strains and different concentrations of extracted lipoproteins induced a higher gene expression of IL-1β, TNF-α, TLR2, and TLR4 in macrophages (p < 0.05) when compared to non-infected cells. The used blockers inhibited the expression of IL-1β and TNF-α in all treatments. Moreover, U. diversum was able to internalize within blastocysts and induce a higher gene expression of IL-1b and TNF- α when compared to non-infected blastocysts (p < 0.05). Conclusion: The obtained results strongly suggest that U. diversum and its lipoproteins interact with TLR4 in a signaling pathway acting via NF-kB signaling to stimulate the inflammatory response. This is the first study to evaluate the in vitro immunological response of macrophages and bovine blastocysts against U. diversum. These results may contribute to a better understanding of the immunomodulatory activity and pathogenicity of this infectious agent.


Fertility and Sterility | 2018

Mycoplasma genitalium can modulate the local immune response in patients with endometriosis

Guilherme Campos; Lucas M. Marques; Izadora S. Rezende; Maysa S. Barbosa; Mauricio Simões Abrão; Jorge Timenetsky

OBJECTIVE To detect Mollicutes in women with endometriosis and healthy peritoneal tissues and evaluate the participation of these bacteria in the immune response during endometriosis. DESIGN Cross-sectional study. SETTING University hospitals. PATIENT (S) Women with endometriosis (n = 73) and without endometriosis (n = 31). INTERVENTION(S) Endocervical swabs, peritoneal fluid, and biopsied lesions of endometriosis of women with endometriosis (study group) and healthy peritoneal tissues (control group) were collected during surgery. Clinical characteristics were registered before surgery. MAIN OUTCOME MEASURE(S) We determined the infectious agents with the use of quantitative polymerase chain reaction (PCR). The cytokine secretion profile was determined with the use of Luminex. The expression of immune response related genes was determined with the use of a PCR array kit. RESULT(S) All target microorganisms were detected at least once in the swab samples analyzed. It was possible to observe higher diversity of microorganisms in the samples of swab and peritoneal fluid in the study group compared with the control. Ureaplasma parvum was associated with the severity of the symptom dyspareunia. Mycoplasma genitalium was associated with higher production of interferon-γ and interleukin-1β. Genes of inflammatory response activation and antigen presentation were up-regulated in biopsied tissue of women with endometriosis. In women with endometriosis, peritoneal fluid cells showed a down-regulation of genes associated with the inflammatory response. This down-regulation profile was higher in presence of M. genitalium. CONCLUSION(S) Mycoplasma genitalium may play a key role in the immune tolerance process and, especially, the aggravation of this profile. More studies are needed to understand this immune tolerance profile of bacterial infections.

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