RONALDO CESAR BORGES GRYSCHEK
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina - Docente
LIM/06 - Laboratório de Imunopatologia da Esquistossomose e outras Parasitoses, Hospital das Clínicas, Faculdade de Medicina
LIM/06 - Laboratório de Imunopatologia da Esquistossomose e outras Parasitoses, Hospital das Clínicas, Faculdade de Medicina
11 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 11
- MEMBRANE FRACTIONS FROM Strongyloides venezuelensis IN THE IMMUNODIAGNOSIS OF HUMAN STRONGYLOIDIASIS(2015) CORRAL, Marcelo Andreetta; PAULA, Fabiana Martins; GOTTARDI, Maiara; MEISEL, Dirce Mary Correia Lima; CHIEFFI, Pedro Paulo; GRYSCHEK, Ronaldo Cesar BorgesStrongyloides venezuelensis is a parasitic nematode of rodents frequently used to obtain heterologous antigens for the immunological diagnosis of human strongyloidiasis. The aim of this study was to evaluate membrane fractions from S. venezuelensis for human strongyloidiasis immunodiagnosis. Soluble and membrane fractions were obtained in phosphate saline (SS and SM) and Tris-HCl (TS and TM) from filariform larvae of S. venezuelensis. Ninety-two serum samples (n = 92) were obtained from 20 strongyloidiasis patients (Group I), 32 from patients with other parasitic diseases (Group II), and 40 from healthy individuals (Group III), and were analyzed by enzyme-linked immunosorbent assay (ELISA). Soluble fractions (SS and TS) showed 90.0% sensitivity and 88.9% specificity, whereas the membrane fractions (SM and TM) showed 95.0% sensitivity and 94.4% specificity. The present results suggest the possible use of membrane fractions of S. venezuelensis as an alternative antigen for human strongyloidiasis immunodiagnosis.
- Strongyloides infection screening in transplant candidates: What is the best strategy?(2023) GRYSCHEK, Ronaldo Cesar Borges; CORRAL, Marcelo Andreetta; SITTA, Renata Barnabe; GOTTARDI, Maiara; PIERROTTI, Ligia Camera; COSTA, Silvia Figueiredo; ABDALA, Edson; CHIEFFI, Pedro Paulo; PAULA, Fabiana Martins deBackground: The potential that Strongyloides stercoralis infection has to cause major morbidity and high mortality when the disseminated form occurs in transplant patients is of particular concern.Methods: In this study, the objective was to observe S. stercoralis infection in patients who are candidates for transplantation by using parasitological, serological, and molecular techniques and to propose an algorithm for the detection of that infection in transplant candidates.Results: By parasitological techniques, 10% of fecal samples were positive. Anti-Strongyloides antibodies immunoglobulin G were detected in 19.3% and 20.7% of patients by immunofluorescence assay and enzyme-linked immunosorbent assay, respectively. S. stercoralis DNA was observed in 17.3% of samples by conventional polymerase chain reaction and 32.7% of samples by quantitative polymerase chain reaction (qPCR).Conclusion: The set of results allows us to reinforce that a positive result by parasitological techniques and/or qPCR indicates that the specific treatment should be applied. However, the improvement of diagnostic techniques may suggest changes in the screening for strongyloidiasis in these patients. image
- DIAGNOSIS OF Strongyloides stercoralis INFECTION IN IMMUNOCOMPROMISED PATIENTS BY SEROLOGICAL AND MOLECULAR METHODS(2016) PAULA, Fabiana Martins de; MALTA, Fernanda Mello; CORRAL, Marcelo Andreetta; MARQUES, Priscilla Duarte; GOTTARDI, Maiara; MEISEL, Dirce Mary Correia Lima; YAMASHIRO, Juliana; PINHO, Joao Renato Rebello; CASTILHO, Vera Lucia Pagliusi; GONCALVES, Elenice Messias do Nascimento; GRYSCHEK, Ronaldo Cesar Borges; CHIEFFI, Pedro PauloStrongyloidiasis is a potentially serious infection in immunocompromised patients. Thus, the availability of sensitive and specific diagnostic methods is desirable, especially in the context of immunosuppressed patients in whom the diagnosis and treatment of strongyloidiasis is of utmost importance. In this study, serological and molecular tools were used to diagnose Strongyloides stercoralis infections in immunosuppressed patients. Serum and stool samples were obtained from 52 patients. Stool samples were first analyzed by Lutz, Rugai, and Agar plate culture methods, and then by a quantitative real time polymerase chain reaction (qPCR). Serum samples were evaluated by an enzyme-linked immunosorbent assay (ELISA) using a soluble (AS) or a membrane fractions antigen (AM) obtained from alkaline solutions of the filariform larvae of Strongyloides venezuelensis. Of the 52 immunosuppressed patients, three (5.8%) were positive for S. stercoralis by parasitological methods, compared to two patients (3.8%) and one patient (1.9%) who were detected by ELISA using the AS and the AM antigens, respectively. S. stercoralis DNA was amplified in seven (13.5%) stool samples by qPCR. These results suggest the utility of qPCR as an alternative diagnostic tool for the diagnosis of S. stercoralis infection in immunocompromised patients, considering the possible severity of this helminthiasis in this group of patients.
- IS THE AGAR PLATE CULTURE A GOOD TOOL FOR THE DIAGNOSIS OF Strongyloides stercoralis IN CANDIDATES FOR TRANSPLANTATION?(2013) PAULA, Fabiana Martins de; GOTTARDI, Maiara; CORRAL, Marcelo Andreetta; CHIEFFI, Pedro Paulo; GRYSCHEK, Ronaldo Cesar Borges
- PARASITOLOGICAL AND MOLECULAR DIAGNOSIS IN EXPERIMENTAL Strongyloides venezuelensis INFECTION(2013) PAULA, Fabiana Martins; SITTA, Renata Barnabe; MALTA, Fernanda Mello; GOTTARDI, Maiara; CORRAL, Marcelo Andreetta; GRYSCHEK, Ronaldo Cesar Borges; CHIEFFI, Pedro PauloStrongyloides venezuelensis is a parasitic nematode of rats which is frequently used as a model to study human and animal strongyloidiasis. The aim of this study was to evaluate the correlation between parasitological and molecular diagnosis in Strongyloides venezuelensis infection. PCR assays were used to detect S. venezuelensis DNA in fecal samples obtained from experimentally infected Rattus norvegicus. The results showed a higher sensitivity of the PCR assay in detecting the infection compared to parasitological methods.
- Toxocara canis 30-35 kDa excretory-secretory antigen is an important marker in mice challenged by inocula containing different parasite load levels(2022) FONSECA, Gabriela Rodrigues e; CORRAL, Marcelo Andreetta; PAULA, Fabiana Martins de; MEISEL, Dirce Mary Correia Lima; GRYSCHEK, Ronaldo Cesar Borges; LESCANO, Susana Angelica ZevallosThe Western-blotting technique was applied to identify antigenic fractions of excretory-secretory Toxocara canis antigen recognized by IgG antibodies throughout an experimental infection in mice challenged by different inocula. Mice were inoculated with 5, 50 and 500 embryonated eggs and serum samples were collected 15, 30, 60, 90 and 120 days post-infection. Serum samples were analyzed using an excretory-secretory Toxocara antigen. Antibodies recognized antigenic fractions from 30 to 90 kDa. The protein fraction of 30-35 kDa was the most frequently recognized regardless of the size of inoculum and the stage of infection represented by the different collection times, but the antigenic recognition was more evident in groups infected with 50 and 500 eggs. This study presents an antigenic panel of the excretory secretory antigen of T. canis and suggests that the 30-35 kDa antigenic fraction is a promising marker of the infection and should be further explored in future studies on experimental toxocariasis.
- COVID-19 and strongyloidiasis: what to expect from this coinfection?(2021) PEREIRA, Carolina Victoria Marcitelli; MASTANDREA, Giovanna Ribeiro Achur; MEDEIROS, Ana Clara Cassine de Souza; GRYSCHEK, Ronaldo Cesar Borges; PAULA, Fabiana Martins de; CORRAL, Marcelo Andreetta
- Evaluation of the Dot-ELISA as a diagnostic test for human strongyloidiasis based on the detection of IgA in saliva(2020) BOSQUI, Larissa Rodrigues; CORRAL, Marcelo Andreetta; LEVY, Debora; BYDLOWSKI, Sergio Paulo; GRYSCHEK, Ronaldo Cesar Borges; CUSTODIO, Luiz Antonio; PAVANELLI, Wander Rogerio; CONCHON-COSTA, Ivete; COSTA-CRUZ, Julia Maria; PAULA, Fabiana Martins de; COSTA, Idessania NazarethThis study aimed to evaluate the use of saliva samples in the Dot-ELISA test for immunodiagnosis of human strongyloidiasis. The Dot-ELISA presented similar results to the ELISA test, with 70% and 60% sensitivity and 85% and 90% specificity, respectively, for IgA in the saliva. The Dot-ELISA with alternative saliva samples may be a suitable tool for diagnosing human strongyloidiasis, especially in populations with high levels of exposure to helminth.
- Diagnosis of human strongyloidiasis: Application in clinical practice(2021) COSTA, Idessania Nazareth; BOSQUI, Larissa Rodrigues; CORRAL, Marcelo Andreetta; COSTA-CRUZ, Julia Maria; GRYSCHEK, Ronaldo Cesar Borges; PAULA, Fabiana Martins deThis review considers the advantages and disadvantages of parasitological techniques, methods of detecting antibodies and antigens, as well as molecular biology techniques in the diagnosis of human strongyloidiasis. In addition, it elucidates the potential of different techniques for rapid and effective detection of clinical cases, thus enabling early treatment and preventing fatal consequences of this helminthiasis.
- IMMUNODIAGNOSIS OF HUMAN STRONGYLOIDIASIS: USE OF SIX DIFFERENT ANTIGENIC FRACTIONS FROM Strongyloides venezuelensis PARASITIC FEMALES(2015) CORRAL, Marcelo Andreetta; PAULA, Fabiana Martins de; GOTTARDI, Maiara; MEISEL, Dirce Mary Correia Lima; CASTILHO, Vera Lucia Pagliusi; GONCALVES, Elenice Messias do Nascimento; CHIEFFI, Pedro Paulo; GRYSCHEK, Ronaldo Cesar BorgesThe aim of this study was to evaluate six different antigenic fractions from Strongyloides venezuelensis parasitic females for the immunodiagnosis of human strongyloidiasis. Soluble and membrane fractions from S. venezuelensis parasitic females were prepared in phosphate-buffered saline (SSF and SMF, respectively), Tris-HCl (TSF and TMF, respectively), and an alkaline buffer (ASF and AMF, respectively). Serum samples obtained from patients with strongyloidiasis or, other parasitic diseases, and healthy individuals were analyzed by enzyme-linked immunosorbent assay (ELISA). Soluble fractions SSF, TSF, and ASF showed 85.0%, 75.0%, and 80.0% sensitivity and 93.1%, 93.1%, and 87.5% specificity, respectively. Membrane fractions SMF, TMF, and AMF showed 80.0%, 75.0%, and 85.0% sensitivity, and 95.8%, 90.3%, and 91.7% specificity, respectively. In conclusion, the present results suggest that the fractions obtained from parasitic females, especially the SSF and SMF, could be used as alternative antigen sources in the serodiagnosis of human strongyloidiasis.