ANTONIO WALTER FERREIRA

(Fonte: Lattes)
Índice h a partir de 2011
7
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina - Docente
LIM/48 - Laboratório de Imunologia, Hospital das Clínicas, Faculdade de Medicina

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  • article
    II Consenso Brasileiro em Doença de Chagas, 2015
    (2016) DIAS, João Carlos Pinto; RAMOS JR., Alberto Novaes; GONTIJO, Eliane Dias; LUQUETTI, Alejandro; SHIKANAI-YASUDA, Maria Aparecida; COURA, José Rodrigues; TORRES, Rosália Morais; MELO, José Renan da Cunha; ALMEIDA, Eros Antonio de; OLIVEIRA JR., Wilson de; SILVEIRA, Antônio Carlos; REZENDE, Joffre Marcondes de; PINTO, Fabiane Scalabrini; FERREIRA, Antonio Walter; RASSI, Anis; FRAGATA FILHO, Abílio Augusto; SOUSA, Andréa Silvestre de; CORREIA FILHO, Dalmo; JANSEN, Ana Maria; ANDRADE, Glaucia Manzan Queiroz; BRITTO, Constança Felícia De Paoli de Carvalho; PINTO, Ana Yecê das Neves; RASSI JR., Anis; CAMPOS, Dayse Elisabeth; ABAD-FRANCH, Fernando; SANTOS, Silvana Eloi; CHIARI, Egler; HASSLOCHER-MORENO, Alejandro Marcel; MOREIRA, Eliane Furtado; MARQUES, Divina Seila de Oliveira; SILVA, Eliane Lages; MARIN-NETO, José Antonio; GALVÃO, Lúcia Maria da Cunha; XAVIER, Sergio Salles; VALENTE, Sebastião Aldo da Silva; CARVALHO, Noêmia Barbosa; CARDOSO, Alessandra Viana; SILVA, Rafaella Albuquerque e; COSTA, Veruska Maia da; VIVALDINI, Simone Monzani; OLIVEIRA, Suelene Mamede; VALENTE, Vera da Costa; LIMA, Mayara Maia; ALVES, Renato Vieira
    ABSTRACT Chagas disease is a neglected chronic condition that presents high morbidity and mortality burden, with considerable psychological, social, and economic impact. The disease represents a significant public health issue in Brazil, with different regional patterns. This document presents the evidence that resulted in the Brazilian Consensus on Chagas Disease. The objective was to review and standardize strategies for diagnosis, treatment, prevention, and control of Chagas disease in the country, based on the available scientific evidence. The consensus is based on collaboration and contribution of renowned Brazilian experts with vast knowledge and experience on various aspects of the disease. It is the result of close collaboration between the Brazilian Society of Tropical Medicine and the Ministry of Health. This document shall strengthen the development of integrated control measures against Chagas disease in the country, focusing on epidemiology, management, comprehensive care (including families and communities), communication, information, education, and research.
  • article 220 Citação(ões) na Scopus
    2nd Brazilian Consensus on Chagas Disease, 2015
    (2016) DIAS, Joao Carlos Pinto; RAMOS JR., Alberto Novaes; GONTIJO, Eliane Dias; LUQUETTI, Alejandro; SHIKANAI-YASUDA, Maria Aparecida; COURA, Jose Rodrigues; TORRES, Rosalia Morais; MELO, Jose Renan da Cunha; ALMEIDA, Eros Antonio de; OLIVEIRA JUNIOR, Wilson de; SILVEIRA, Antonio Carlos; REZENDE, Joffre Marcondes de; PINTO, Fabiane Scalabrini; FERREIRA, Antonio Walter; RASSI, Anis; FRAGATA FILHO, Abilio Augusto; SOUSA, Andrea Silvestre de; CORREIA, Dalmo; JANSEN, Ana Maria; ANDRADE, Glaucia Manzan Queiroz; BRITTO, Constana Felicia De Paoli de Carvalho; PINTO, Ana Yece das Neves; RASSI JUNIOR, Anis; CAMPOS, Dayse Elisabeth; ABAD-FRANCH, Fernando; SANTOS, Silvana Eloi; CHIARI, Egler; HASSLOCHER-MORENO, Alejandro Marcel; MOREIRA, Eliane Furtado; MARQUES, Divina Seila de Oliveira; SILVA, Eliane Lages; MARIN-NETO, Jose Antonio; GALVAO, Lucia Maria da Cunha; XAVIER, Sergio Salles; VALENTE, Sebastiao Aldo da Silva; CARVALHO, Noemia Barbosa; CARDOSO, Alessandra Viana; SILVA, Rafaella Albuquerque e; COSTA, Veruska Maia da; VIVALDINI, Simone Monzani; OLIVEIRA, Suelene Mamede; VALENTE, Vera da Costa; LIMA, Mayara Maia; ALVES, Renato Vieira
    Chagas disease is a neglected chronic condition with a high burden of morbidity and mortality. It has considerable psychological, social, and economic impacts. The disease represents a significant public health issue in Brazil, with different regional patterns. This document presents the evidence that resulted in the Brazilian Consensus on Chagas Disease. The objective was to review and standardize strategies for diagnosis, treatment, prevention, and control of Chagas disease in the country, based on the available scientific evidence. The consensus is based on the articulation and strategic contribution of renowned Brazilian experts with knowledge and experience on various aspects of the disease. It is the result of a close collaboration between the Brazilian Society of Tropical Medicine and the Ministry of Health. It is hoped that this document will strengthen the development of integrated actions against Chagas disease in the country, focusing on epidemiology, management, comprehensive care (including families and communities), communication, information, education, and research.
  • article 6 Citação(ões) na Scopus
    Anti-Leishmania infantum IgG Antibody Avidity in Visceral Leishmaniasis
    (2013) TIBURCIO, Monique Gomes Salles; ANVERSA, Lais; KANUNFRE, Kelly Aparecida; FERREIRA, Antonio Walter; RODRIGUES JUNIOR, Virmondes; SILVA, Luciana de Almeida
    IgG avidity tests are used to discriminate acute from chronic infections. There are few reports on the IgG avidity profile of patients with visceral leishmaniasis (VL). This study investigated the anti-Leishmania IgG avidity in patients with classic VL (n = 10), patients showing clinical cure after treatment (n = 18), and asymptomatic subjects with at least one positive Leishmania test (n = 20). All subjects were from areas in Brazil where VL is endemic. Serum samples were collected from each subject on two different occasions. IgG avidity was evaluated by Western blotting. The proportion of high-avidity antibodies was higher in all samples from patients with classic VL. In contrast, low-avidity antibodies predominated in subjects with a history of VL, including 13 cases (72.2%) in the first assessment and 14 (77.8%) in the second. Fifteen (75%) of the asymptomatic subjects presented a predominance of low-avidity antibodies in the first assessment, and the frequency of high-avidity antibodies increased over time in seven subjects (35%) of this group. Antibodies against the 14- and/or 16-kDa antigen fraction were detected in the first assessment in all patients with classic VL, in 10 (55.5%) treated patients, and in 10 (50%) asymptomatic subjects. These were high-avidity antibodies in most cases. In the asymptomatic group, an increase in IgG avidity against the 14- and/or 16-kDa antigen fraction was observed in three cases (15%). The results indicate distinct responses in infected and asymptomatic subjects, probably associated with the length of time after infection. In this respect, IgG avidity tests represent a new approach to better characterize asymptomatic VL.
  • article 5 Citação(ões) na Scopus
    Immunoglobulin M antibodies are not specific for serodiagnosis of human toxocariasis
    (2017) ROLDAN, W. H.; ELEFANT, G. R.; FERREIRA, A. W.
    Serodiagnosis of human toxocariasis is established by detecting serum anti-Toxocara IgG antibodies, but there is little knowledge regarding the reactivity of human IgM antibodies against the Toxocara antigens. In this study, we have evaluated the reactivity of IgM antibodies in sera from patients with toxocariasis, patients with other helminth infections, and healthy individuals, against Toxocara larval excretory-secretory (TES) antigens by enzyme-linked immunosorbent assay (ELISA) and Western blot (WB). Anti-Toxocara IgM were detected in 91.4% of sera from patients with toxocariasis, 76% of sera from patients with other helminth infections, and 45.3% of sera from healthy individuals when ELISA was used. Likewise, IgM antibodies were detected in 94.8% of sera from patients with toxocariasis, 65.3% of sera from patients with other helminth infections, and 41% of sera from healthy individuals when WB was used. This reactivity exhibited only a slight decrease when the TES antigens were deglycosylated, showing that not only glycosidic epitopes, but also peptide epitopes are involved in the recognition and binding of IgM antibodies during the immune response against the parasite. The results shown that IgM antibodies are not specific for serodiagnosis of human toxocariasis.
  • article 21 Citação(ões) na Scopus
    POTENTIAL IMMUNOLOGICAL MARKERS FOR DIAGNOSIS AND THERAPEUTIC ASSESSMENT OF TOXOCARIASIS
    (2011) RUBINSKY-ELEFANT, Guita; HOSHINO-SHIMIZUI, Sumie; JACOB, Cristina Miuki Abe; SANCHEZ, Maria Carmen Arroyo; FERREIRA, Antonio Walter
    In human toxocariasis, there are few approaches using immunological markers for diagnosis and therapeutic assessment. An immunoblot (IB) assay using excretory-secretory Toxocara canis antigen was standardized for monitoring IgG, IgE and IgA antibodies in 27 children with toxocariasis (23 visceral, three mixed visceral and ocular, and one ocular form) for 22-116 months after chemothetapy. IB sensitivity was 100% for IgG antibodies to bands of molecular weight 29-38, 48-54, 95-116, 121-162, >205 kDa, 80.8% for IgE to 29-38, 48-54, 95-121, >205 kDa, and 65.4% for IgA to 29-38, 48-54, 81-93 kDa. Candidates for diagnostic markers should be IgG antibodies to bands of low molecular weight (29-38 and 48-54 kDa). One group of patients presented the same antibody reactivity to all bands throughout the follow-up study; in the other group, antibodies decayed partially or completely to some or all bands, but these changes were not correlated with time after chemotherapy. Candidates for monitoring patients after chemotherapy may be IgG antibodies to > 205 kDa fractions, IgA to 29-38, 48-54, 81-93 kDa and IgE to 95-121 kDa. Further identification of antigen epitopes related to these markers will allow the development of sensitive and specific immunoassays for the diagnosis and therapeutic assessment of toxocariasis.
  • article 15 Citação(ões) na Scopus
    Deglycosylation of Toxocara excretory-secretory antigens improves the specificity of the serodiagnosis for human toxocariasis
    (2015) ROLDAN, W. H.; ELEFANT, G. R.; FERREIRA, A. W.
    Serodiagnosis of human toxocariasis is difficult in tropical areas where other helminthiasis are endemic. Many studies have shown that glycans from helminths may be the responsible for cross-reactions in the immunoassays. In this study, we have evaluated the deglycosylation of the Toxocara canis excretory-secretory (TES) antigens for the detection of IgG antibodies using a panel of 228 serum samples (58 patients with toxocariasis, 75 patients with other helminth infections and 95 healthy individuals) by ELISA and Western blot assays. Our results showed that the deglycosylation of TES antigens resulted in a single fraction of 26 kDa (dTES) and was able to detect IgG antibodies with a sensitivity and specificity of 100% in both above-mentioned assays. The rate of cross-reactions, observed in ELISA with TES (133%), was significantly reduced (53%) when the dTES antigens were used. Likewise, the cross-reactivity observed with the fractions of 32, 55 and 70 kDa of the TES antigens was totally eliminated when the dTES were used in the Western blot. All these results showed that the deglycosylation of the TES antigens really improves the specificity of the serodiagnosis of human toxocariasis in endemic areas for helminth infections.
  • article 24 Citação(ões) na Scopus
    Seroprevalence of toxoplasmosis, toxocariasis and cysticercosis in a rural settlement, Sao Paulo State, Brazil
    (2013) PRESTES-CARNEIRO, Luiz Euribel; RUBINSKY-ELEFANT, Guita; FERREIRA, Antonio Walter; ARAUJO, Patricia Regina; TROIANI, Charlene; ZAGO, Sueli Cristina; KAIAHARA, Marcia; SASSO, Leticia; IHA, Alberto; VAZ, Adelaide
    Background: The goal of this study was to estimate the seroprevalence of Toxocara spp., Toxoplasma gondii, and Taenia solium metacestode infection and determine some of the associated risk factors for people living in the Dona Carmen settlement, Pontal of Paranapanema, Sao Paulo, Brazil. Methods: Serum samples from 194 subjects were tested and participants answered a questionnaire. An enzyme-linked immunosorbent assay (ELISA) system based on Toxocara spp. excretory-secretory antigens obtained from the cultured second-stage larvae of Toxocara canis or vesicular fluid (VF) antigen from Taenia crassiceps metacestode was used to detect anti-Toxocara spp. IgG and IgE and anti-T. solium metacestode, respectively. For cysticercosis, the reactive ELISA samples were assayed by Western blotting using 18 kDa and 14 kDa proteins purified from VF. For T. gondii-specific IgG and IgM antibodies, anti-SAG-1, GRA-1, and GRA-7 epitope specificity was determined by ELISA. Results: Toxoplasma gondii IgG antibodies were found in 102/194 individuals (52.6%) with increased infections in females (P=0.02) and those with <= US$300 monthly income (P=0.01). Positive IgM antibodies were detected in 21/194 individuals (10.8%). Antibodies specific to Toxocara spp. were found in 28/194 subjects (14.4%). All the individuals with Toxocara spp. also had T. gondii-specific IgG antibodies. Taenia solium metacestode antibodies were detected in 11 subjects (5.7%), but none were reactive based on Western blotting. Conclusion: In spite of environmental, educational, and socioeconomic factors favoring parasite infection, the seropositivity rates of T. gondii, Toxocara spp., and T. solium metacestode-specific IgG antibodies are similar to the rates found in studies conducted in different populations in Brazil.
  • article 7 Citação(ões) na Scopus
    Western blotting method (TESAcruzi) as a supplemental test for confirming the presence of anti-Trypanosoma cruzi antibodies in finger prick blood samples from children aged 0-5 years in Brazil
    (2011) FRADE, Amanda Farage; LUQUETTI, Alejandro O.; PRATA, Aluisio; FERREIRA, Antonio Walter
    Some Latin American countries have plans for total control and/or eradication of Chagas disease by the main vector (Triatoma infestans) and by blood transfusion. To achieve this, patients with Chagas disease must be identified. A Western blotting test, TESAcruzi, is described as a supplemental test for diagnosis of Chagas disease using samples collected from children <5 years living in different states of Brazil. Blood samples collected by finger prick on filter paper were sent to the test laboratory by a central laboratory to confirm results obtained previously. Ten percent of negative samples, all doubtful and all positive samples were received. Commercial reagents, IgG indirect immunofluorescence, enzyme immunoassay, and a recently introduced TESAcruzi test were used. From 8788 samples, 163 (1.85%) were reactive by IgG-ELISA and 312 (3.55%) by IgG IIF. From these, 77 (0.87%) were reactive in the TESAcruzi test. The results had high clinical value to identify those truly infected.
  • article 27 Citação(ões) na Scopus
    Soil contamination by eggs of soil-transmitted helminths with zoonotic potential in the town of Fernandopolis, State of Sao Paulo, Brazil, between 2007 and 2008
    (2011) CASSENOTE, Alex Jones Flores; PINTO NETO, Jose Martins; LIMA-CATELANI, Alba Regina de Abreu; FERREIRA, Antonio Walter
    Introduction: The concentration of dogs and cats in urban areas, associated with an ever-increasing wandering population of these animals, has an important epidemiological role in the soil contamination of public spaces and the spread of infections of several types of parasites. This study aimed to determine the frequency of soil-transmitted helminths with zoonotic potential in public squares and municipal primary schools in Fernandopolis, State of Sao Paulo, Brazil, conducted between 2007 and 2008. Methods: All the squares (32) and schools (13) in the town were evaluated. Soil samples were tested using the Rugai method modified by Willis, Caldwell and Caldwell. Results: A total of 225 soil samples were evaluated and 30.2% (68) were positive for helminths. In samples from public squares, 40% (64) contamination was observed; however, contamination in schools was only 6.1% (6). The parasites eggs identified were Toxocara spp. 79.3% (47), Trichuris spp. 13.8% (8) and Ancylostomatidae 6.9% (4). Variables related to the site, such as the number of dogs (OR 21.18, 10.81-41.51), fecal samples (OR 6.87, 3.51-13.47) and the use of fences (OR 0.1, 0.05-0.20), had an impact on soil contamination. Conclusions: In the contaminated samples, parasites with zoonotic potential were identified, including the etiologic agents of diseases like cutaneous and visceral larva migrans, a fact that poses a risk to health of the population that frequent such environments.
  • article 68 Citação(ões) na Scopus
    O inquérito nacional de soroprevalência de avaliação do controle da doença de Chagas no Brasil (2001-2008)
    (2011) OSTERMAYER, Alejandro Luquetti; PASSOS, Afonso Dinis Costa; SILVEIRA, Antonio Carlos; FERREIRA, Antonio Walter; MACEDO, Vanize; PRATA, Aluizio Rosa
    A survey for seroprevalence of Chagas disease was held in a representative sample of Brazilian individuals up to 5 years of age in all the rural areas of Brazil, with the single exception of Rio de Janeiro State. Blood on filter paper was collected from 104,954 children and screened in a single laboratory with two serological tests: indirect immunofluorescence and enzyme linked immunoassay. All samples with positive or indetermined results, as well as 10% of all the negative samples were submitted to a quality control reference laboratory, which performed both tests a second time, as well as the western blot assay of TESA (Trypomastigote Excreted Secreted Antigen). All children with confirmed final positive result (n = 104, prevalence = 0.1%) had a follow-up visit and were submitted to a second blood collection, this time a whole blood sample. In addition, blood samples from the respective mothers and familiar members were collected. The infection was confirmed in only 32 (0.03%) of those children. From them, 20 (0.025%) had maternal positive results, suggesting congenital transmission; 11 (0.01%) had non-infected mothers, indicating a possible vectorial transmission; and in one whose mother had died the transmission mechanism could not be elucidated. In further 41 visited children the infection was confirmed only in their mothers, suggesting passive transference of maternal antibodies; in other 18, both child and mother were negative; and in 13 cases both were not localized. The 11 children that acquired the infection presumably through the vector were distributed mainly in the Northeast region of Brazil (States of Piaui, Ceara, Rio Grande do Norte, Paraiba and Alagoas), in addition to one case in Amazonas (North region) and another in Parana (South region). Remarkably, 60% of the 20 cases of probably congenital transmission were from a single State, Rio Grande do Sul, with the remaining cases distributed in other states. This is the first report demonstrating regional geographical differences in the vertical transmission of Chagas disease in Brazil, which probably reflects the predominant Trypanosoma cruzi group IId and IIe (now TcV and TcVI) found in this state. Overall, these results show that the regular and systematic control programs against the transmission of Chagas disease, together with socioeconomic changes observed in Brazil in the last decades, interrupted the vectorial transmission in Brazil, resumed in the few cases found in this national survey. Furthermore they reinforce the need for maintenance of control programs for the consolidation of this major advance in public health.