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Dive into the research topics where Andrea Pires dos Santos is active.

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Featured researches published by Andrea Pires dos Santos.


Emerging Infectious Diseases | 2008

Hemoplasma infection in HIV-positive patient, Brazil.

Andrea Pires dos Santos; Rodrigo Pires dos Santos; Alexander Welker Biondo; José Miguel Dora; Luciano Zubaran Goldani; Simone Tostes de Oliveira; Ana Maárcia de Sá Guimarães; Jorge Timenetsky; Helio Autran de Morais; Felix Hilario Diaz Gonzalez; Joanne B. Messick

Hemotrophic mycoplasmas infect a variety of mammals. Although infection in humans is rarely reported, an association with an immunocompromised state has been suggested. We report a case of a Mycoplasma haemofelis–like infection in an HIV-positive patient co-infected with Bartonella henselae.


Revista Brasileira De Parasitologia Veterinaria | 2011

Ehrlichiosis in Brazil.

Rafael Felipe da Costa Vieira; Alexander Welker Biondo; Ana M. S. Guimaraes; Andrea Pires dos Santos; Rodrigo Pires dos Santos; Leonardo Hermes Dutra; Pedro Paulo Vissotto de Paiva Diniz; Helio Autran de Morais; Joanne B. Messick; Marcelo Bahia Labruna; Odilon Vidotto

Erliquiose e uma doenca causada por rickettsias pertencentes ao genero Ehrlichia. No Brasil, estudos sorologicos e moleculares tem avaliado a ocorrencia de especies de Ehrlichia em caes, gatos, animais selvagens e seres humanos. Ehrlichia canis e a principal especie em caes no Brasil, embora a infeccao por E. ewingii tenha, recentemente, despertado suspeita em cinco caes. O DNA de E. chaffeensis foi detectado e caracterizado em cervo-do-pantanal, enquanto que E. muris e E. ruminantium ainda nao foram identificadas no Brasil. A erliquiose monocitica canina causada pela E. canis parece ser altamente endemica em muitas regioes do Brasil, embora dados de prevalencia nao estejam disponiveis em muitas delas. O DNA de E. canis tambem foi detectado e caracterizado em tres gatos domesticos, enquanto anticorpos contra E. canis foram detectados em felideos neotropicais de vida livre. Evidencias sorologicas sugerem a ocorrencia de erliquiose humana no Brasil, entretanto, o agente etiologico ainda nao foi identificado. A melhoria do diagnostico molecular promovera a identificacao e caracterizacao de especies associadas a erliquiose humana no Brasil.Ehrlichiosis is a disease caused by rickettsial organisms belonging to the genus Ehrlichia. In Brazil, molecular and serological studies have evaluated the occurrence of Ehrlichia species in dogs, cats, wild animals and humans. Ehrlichia canis is the main species found in dogs in Brazil, although E. ewingii infection has been recently suspected in five dogs. Ehrlichia chaffeensis DNA has been detected and characterized in mash deer, whereas E. muris and E. ruminantium have not yet been identified in Brazil. Canine monocytic ehrlichiosis caused by E. canis appears to be highly endemic in several regions of Brazil, however prevalence data are not available for several regions. Ehrlichia canis DNA also has been detected and molecularly characterized in three domestic cats, and antibodies against E. canis were detected in free-ranging Neotropical felids. There is serological evidence suggesting the occurrence of human ehrlichiosis in Brazil but its etiologic agent has not yet been established. Improved molecular diagnostic resources for laboratory testing will allow better identification and characterization of ehrlichial organisms associated with human ehrlichiosis in Brazil.


Helicobacter | 2011

Prevalence and incidence of Helicobacter pylori Infection in a healthy pediatric population in the Lisbon area

Mónica Oleastro; Ana Pelerito; Paulo Nogueira; João Benoliel; Andrea Pires dos Santos; José Cabral; Ana Isabel Lopes; Paulo Ramalho; Lurdes Monteiro

Background:  Helicobacter pylori is mainly acquired in childhood. Although adult studies reported a high prevalence of H. pylori infection in Portugal, the actual rate in children remains unknown. This study aimed to determine the prevalence and the incidence of H. pylori infection in an asymptomatic pediatric population of the Lisbon area and to correlate prevalence with sociodemographic determinants.


Journal of Antimicrobial Chemotherapy | 2011

Primary antibiotic resistance of Helicobacter pylori strains isolated from Portuguese children: a prospective multicentre study over a 10 year period

Mónica Oleastro; José Cabral; Paulo Ramalho; Piedade Sande Lemos; Eleonora Paixão; João Benoliel; Andrea Pires dos Santos; Ana Isabel Lopes

OBJECTIVES The aim of this study was to prospectively assess the pattern of evolution of primary resistance to antibiotics in Helicobacter pylori strains isolated from Portuguese children over a 10 year period (2000-09). METHODS A total of 1115 H. pylori strains were tested for antibiotic susceptibility to clarithromycin, metronidazole, amoxicillin, ciprofloxacin and tetracycline. RESULTS H. pylori strains were isolated from children and adolescents [ages 4 months-18 years (mean age 10.17 ± 4.03 years)], comprising 562 (50.4%) boys and 553 (49.6%) girls. Overall, the primary resistance rate was 34.7% to clarithromycin, 13.9% to metronidazole and 4.6% to ciprofloxacin, while 6.9% were resistant to two of these antibiotics simultaneously. Resistance to amoxicillin and to tetracycline was not detected. In general, the resistance rate was not associated with gender or the childrens age. European ethnicity, when compared with an African background, was associated with clarithromycin resistance [P = 0.002; odds ratio (OR) = 0.30; 95% confidence interval (CI) 0.14-0.66], while the inverse situation was observed for metronidazole (P < 0.001; OR = 3.50; 95% CI 1.90-6.45). No significant temporal trend was noticed for resistance to clarithromycin and metronidazole, whereas ciprofloxacin and double-resistance rates have significantly increased over time (P = 0.004 and P = 0.05, respectively). CONCLUSIONS The primary resistance rate of H. pylori strains isolated from Portuguese children to the commonly used anti-H. pylori antibiotics used is high. Additionally, the increasing trend of ciprofloxacin-resistant and double-resistant strains may compromise H. pylori eradication in a high-prevalence population.


Journal of Clinical Microbiology | 2010

Clinical Relevance and Diversity of Two Homologous Genes Encoding Glycosyltransferases in Helicobacter pylori

Mónica Oleastro; Andrea Pires dos Santos; Rita Cordeiro; Baltazar Nunes; Francis Mégraud; Armelle Ménard

ABSTRACT Helicobacter pylori is known to be a major cause of peptic ulceration. The jhp0562 gene, encoding a glycosyltransferase involved in the synthesis of the lipopolysaccharide, was associated with peptic ulcer disease (PUD) in children. The β-(1,3)-galactosyltransferase [β-(1,3)GalT] gene (jhp0563), involved in Lewis (Le) antigen expression, is highly similar to jhp0562. The clinical significance and diversity of both genes were examined by PCR and sequencing of clinical strains (n = 117) isolated from children with PUD (n = 57) and nonulcer dyspepsia (NUD; n = 60). The prevalence of the jhp0562 gene was significantly higher in strains with a more-virulent profile (strains positive for the cag pathogenicity island [PAI], vacA sl allele, babA, homB, phase-variable gene oipA “on” [i.e., functional], and hopQ I allele). The distribution of genotypes according to clinical outcome showed that the presence of jhp0562 represented one of the greatest risks for the development of PUD. Moreover, the triple-positive genotype for the cag PAI, jhp0562, and homB provided the best discriminatory model for distinguishing PUD and NUD outcomes in children. Sequence and in vitro expression analyses of jhp0562 showed the presence of a complete open reading frame, while the β-(1,3)GalT gene was shown to be a phase-variable gene. The regular presence of jhp0562 in strains with a truncated β-(1,3)GalT gene suggests that jhp0562 may also be implicated in the regulation of Le antigen expression. Overall, the results of this study suggest that the jhp0562 gene is of great clinical relevance, being a useful comarker for severe H. pylori-related disease and contributing to host adaptation.


Journal of Veterinary Diagnostic Investigation | 2008

Association of canine obesity with reduced serum levels of C-reactive protein

Angela Veiga; Christopher A. Price; Simone Tostes de Oliveira; Andrea Pires dos Santos; Rómulo Campos; Patrícia Rick Barbosa; Felix Hilario Diaz Gonzalez

The prevalence of obesity is increasing in dogs as well as in humans. C-reactive protein (CRP) is an important tool for the detection of inflammation and/or early tissue damage and is linked to obesity in humans. The objective of the present study was to determine if serum CRP levels are altered in obese dogs. Fifteen lean (control group) and 16 overweight (obese group) dogs were examined. Blood samples were collected under fasted conditions for serum determination of CRP, glucose, insulin, cholesterol, triglyceride, and fructosamine. Results indicated that obese dogs were insulin resistant because serum insulin and insulin/glucose ratios were higher than in lean dogs (P ≤ 0.05). Serum CRP concentrations were lower in obese dogs than in controls (P ≤ 0.001). C-reactive protein was negatively correlated with insulin/glucose ratio (R = −0.42) and cholesterol (R = −0.39; P ≤ 0.05). Furthermore, levels of cholesterol, triglycerides, and fructosamine were increased in the obese group compared with the control group. Based on these results, it can be postulated that CRP production is inhibited by obesity and insulin resistance in dogs.


Veterinary Microbiology | 2011

Mycoplasma ovis in captive cervids: prevalence, molecular characterization and phylogeny.

Ana Laura Grazziotin; Andrea Pires dos Santos; Ana M. S. Guimaraes; Ahmed Mohamed; Zalmir Silvino Cubas; Marcos Oliveira; Leonilda Correia dos Santos; Wanderlei de Moraes; Rafael Felipe da Costa Vieira; Lucélia Donatti; Ivan Roque de Barros Filho; Alexander Welker Biondo; Joanne B. Messick

Hemotrophic mycoplasmas (hemoplasmas) are bacteria that attach to red blood cells of mammals, leading to acute and/or subclinical disease in infected animals. It has been suggested that Mycoplasma ovis, a hemoplasma that infects sheep and goats worldwide, may also infect deer. The aim of this study was to evaluate whether South American deer are infected with M. ovis. EDTA-anticoagulated blood samples from a herd of 32 captive South American deer were collected. DNA extraction of blood samples was performed followed by PCR amplification of the 16S and 23S rRNA genes, and sequencing of products. Using M. ovis PCR, 27/31 (87%) were positive, including 21/22 Mazama nana; 2/3 Mazama americana and 4/6 Blastocerus dichotomus. Sequencing of the nearly entire 16S rRNA gene of 26/27 positive samples showed 98.2-98.8% identity to M. ovis of sheep (GenBank, AF338268) and 98.6-99.4% identity to M. ovis-like of a fawn (FJ824847); the 23S rRNA gene from one of these isolates and the fawns had 97.6% identity. The remaining isolate had just 94.9% identity to the 16S rRNA gene of M. ovis and only 89.4% identity to the 23S rRNA gene of the fawns M. ovis. This is the first report of M. ovis in captive South American deer, revealing a high prevalence of hemoplasma infection in these animals.


Journal of Bacteriology | 2011

Complete Genome Sequences of Two Hemotropic Mycoplasmas, Mycoplasma haemofelis Strain Ohio2 and Mycoplasma suis Strain Illinois

Joanne B. Messick; Andrea Pires dos Santos; Ana M. S. Guimaraes

We report the complete and fully assembled genomes of Mycoplasma haemofelis strain Ohio2 and Mycoplasma suis strain Illinois, which are the first available genomes of these uncultivatable hemoplasma species. The single circular chromosomes of 1,152,484 bp and 742,431 bp for M. haemofelis and M. suis, respectively, are typical of mycoplasma species, having reduced size and low G+C content (38.8% for M. haemofelis and 31.1% for M. suis). Their metabolic pathways are reduced, with evidence of adaption to the blood environment.


Pesquisa Veterinaria Brasileira | 2009

Laparoscopic versus open splenectomy in dogs

Rafael Stedile; Carlos Afonso de Castro Beck; Fabiana Schiochet; Márcio Poletto Ferreira; Simone Tostes de Oliveira; Fernando Barreto Martens; Jardel Pereira Tessari; Sheila B.L. Bernades; Carolina S. Oliveira; Andrea Pires dos Santos; Fabíola Peixoto da Silva Mello; Marcelo Meller Alievi; Marcelo de Souza Muccillo

In the last few years, the use of laparoscopy in veterinary medicine has expanded and consequently so was the need for studies that establish the advantages, disadvantages and possible complications of each procedure. The purpose of the current study was to describe a laparoscopic splenectomy technique and the alterations due to this access, and compare it to the open procedure in dogs. A total of 15 healthy female mongrel dogs were used, with mean weight of 17.4±2.5kg. The animals were distributed into three groups: Group IA of open splenectomy (laparotomy) using double ligation of the vessels of the splenic hilum with poliglicolic acid, Group IB of open splenectomy (laparotomy) with bipolar electrocoagulation of the splenic hilum, and Group II of laparoscopic access with bipolar electrocoagulation of the splenic hilum. Operative time, blood loss, size of incisions, complications during and after surgery were evaluated. Other parameters included pain scores, white blood cell (WBC) counts and postoperative serum concentrations of alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatine kinase (CK), C-reactive protein (CRP), glucose and cortisol. No differences were found in the evaluation of parameters between both open splenectomy techniques employed. Laparoscopic access presented significant differences (p<0,05) when compared with open surgery: Longer operative time, smaller abdominal access, decrease in blood loss, lower concentrations of CRP, higher levels of CK and ALP, and lower scores in the pain scale. Laparoscopic surgery showed fewer complications of the surgical wound. No significant differences were observed between groups in the postoperative temperature, WBC, ALT, cortisol and glucose concentrations. In conclusion, the laparoscopic technique is useful for splenectomy in dogs, being advantageous in terms of blood loss, surgical stress and surgical wounds. However, it expends more operative time and causes transitory increase in hepatic and muscular enzymes.


PLOS ONE | 2011

Ulcerogenic Helicobacter pylori Strains Isolated from Children: A Contribution to Get Insight into the Virulence of the Bacteria

Inês Vitoriano; Kathy Saraiva-Pava; Alexandra Rocha-Gonçalves; Andrea Pires dos Santos; Ana Isabel Lopes; Mónica Oleastro; Mónica Roxo-Rosa

Infection with Helicobacter pylori is the major cause for the development of peptic ulcer disease (PUD). In children, with no other etiology for the disease, this rare event occurs shortly after infection. In these young patients, habits of smoking, diet, consumption of alcohol and non-steroid anti-inflammatory drugs and stress, in addition to the genetic susceptibility of the patient, represent a minor influence. Accordingly, the virulence of the implicated H. pylori strain should play a crucial role in the development of PUD. Corroborating this, our in vitro infection assays comparing a pool of five H. pylori strains isolated from children with PUD to a pool of five other pediatric clinical isolates associated with non-ulcer dyspepsia (NUD) showed the greater ability of PUD strains to induce a marked decrease in the viability of gastric cells and to cause severe damage in the cells cytoskeleton as well as an impairment in the production/secretion of mucins. To uncover virulence features, we compared the proteome of these two groups of H. pylori strains. Two-dimensional gel electrophoresis followed by mass-spectrometry allowed us to detect 27 differentially expressed proteins between them. In addition to the presence of genes encoding well established virulence factors, namely cagA, vacAs1, oipA “on” status, homB and jhp562 genes, the pediatric ulcerogenic strains shared a proteome profile characterized by changes in the abundance of: motility-associated proteins, accounting for higher motility; antioxidant proteins, which may confer increased resistance to inflammation; and enzymes involved in key steps in the metabolism of glucose, amino acids and urea, which may be advantageous to face fluctuations of nutrients. In conclusion, the enhanced virulence of the pediatric ulcerogenic H. pylori strains may result from a synergy between their natural ability to better adapt to the hostile human stomach and the expression of the established virulence factors.

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Felix Hilario Diaz Gonzalez

Universidade Federal do Rio Grande do Sul

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Mónica Oleastro

Instituto Nacional de Saúde Dr. Ricardo Jorge

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Camila Serina Lasta

Universidade Federal do Rio Grande do Sul

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