RONALDO CESAR BORGES GRYSCHEK

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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

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Agora exibindo 1 - 10 de 18
  • conferenceObject
    POTENTIAL IMMUNOLOGICAL MARKERS FOR DIAGNOSIS OF HUMAN STRONGYLOIDIASIS USING HETEROLOGOUS ANTIGENS
    (2017) GRYSCHEK, Ronaldo; CORRAL, Marcelo; PAULA, Fabiana; MEISEL, Dirce; CASTILHO, Vera; GONCALVES, Elenice; LEVY, Debora; BYDLOWSKI, Sergio; CHIEFFI, Pedro Paulo; CASTRO-BORGES, William
  • article 5 Citação(ões) na Scopus
    Diagnostic accuracy of somatic and excretory-secretory antigens from Strongyloides venezuelensis infective larvae for the immunodiagnosis of human strongyloidiasis
    (2021) GONZALES, William Henry Roldan; MEISEL, Dirce Mary Correia Lima; PAULA, Fabiana Martins de; GRYSCHEK, Ronaldo Cesar Borges
    To evaluate the diagnostic accuracy of three types of antigenic preparations from Strongyloides venezuelensis infective larvae for detection of serum IgG anti-Strongyloides antibodies by enzyme-linked immunosorbent assay (ELISA). Soluble somatic fractions (SSF) and membrane somatic fractions (MSF) and excretory-secretory (E/S) products from S. venezuelensis infective larvae were evaluated against 71 sera from individuals with strongyloidiasis, 105 sera from healthy individuals, and 84 sera from individuals with other helminth infections. Using an ELISA cut-off for 100% sensitivity, E/S products were 97.88% specific followed by MSF (93.12%) and then by SSF (85.2%). The occurrence of cross-reactivity with other helminths was 4.76% (4/84) with E/S products, 8.33% (7/84) with MSF, and 17.86% (15/84) with SSF. For a cut-off for 100% specificity, E/S products showed a sensitivity of 88.73% whereas MSF and SSF showed sensitivities of 59.15% and 53.52%, respectively. In conclusion, E/S products were the best antigenic option for the serodiagnosis of human strongyloidiasis.
  • article 0 Citação(ões) na Scopus
    Seroprevalence and associated risk factors of strongyloidiasis in indigenous communities and healthcare professionals from Brazil
    (2023) SANTAREM, Vamilton Alvares; DOLINE, Fernando Rodrigo; SANTOS, Joao Henrique Farinhas dos; FERREIRA, Isabella Braghin; GOMES, Bruna Barroso; MEISEL, Dirce Mary Correa; BIONDO, Leandro Meneguelli; LESCANO, Susana Angelica Zevallos; GRYSCHEK, Ronaldo Cesar Borges; GIUFFRIDA, Rogerio; SANTOS, Andrea Pires dos; KMETIUK, Louise Bach; PAULA, Fabiana Martins de; BIONDO, Alexander Welker
    Author summaryHuman strongyloidiasis, caused mainly by nematoda Strongyloides stercoralis, with estimate of infecting around 613.9 million people worldwide, and may play a pivotal role in causing morbidity in aboriginals and indigenous populations worldwide. Nevertheless, prevalence and risk factors for Strongyloides stercoralis in Brazilian indigenous populations remains to be fully established. The present study was the first comparative report of S. stercoralis seroprevalence in indigenous population and healthcare professionals. A high seroprevalence to Strongyloides stercoralis in indigenous communities of Brazil along with even higher exposure of healthcare professionals was reported and should be considered as vulnerability and health worker exposure. Male and adult indigenous persons were more likely seropositive as associated risk factors, while having septic tank as a sanitary facility represented a protective factor for S. stercoralis exposure. Thus, the present study has alerted for the public health concerns of strongyloidiasis in such vulnerable populations, particularly when lacking sanitation conditions. Finally, a further One Health approach may contribute for better understanding the strongyloidiasis exposure including the environmental, animal, and human components to battle this important parasitic neglected disease in indigenous communities. Strongyloides stercoralis, a pathogenic roundworm, is considered endemic in several tropical and subtropical areas worldwide. Indigenous populations have the highest soil-transmitted helminthiases-related mortality rates, but the prevalence and risk factors associated with S. stercoralis in Brazilian indigenous populations have not been established. Thus, the present study aimed to assess the seroprevalence and associated risk factors for S. stercoralis in indigenous communities and the healthcare professionals serving them in Brazil. Indigenous populations living in nine communities and healthcare professionals were tested for anti- S. stercoralis antibodies by ELISA. A questionnaire was used to assess socio-epidemiological information. Associated risk factors for seropositivity were tested by chi-square or Fisher's exact tests, using bivariate analyses and multivariate logistic regression. Overall, 174/463 (37.6%; CI 95%: 33.3-42.1) indigenous persons and 77/147 (52.4%; 95% CI: 44.3-60.3) healthcare professionals were seropositive for anti- S. stercoralis antibodies. Seropositivity among the two groups was statistically significant (p = 0.0016; OR = 0.547; 95% CI: 0.376-0.796) and revealed that healthcare professionals were 1.83 times more likely to be seropositive. The multivariate analysis showed that being male or being adult were also risk factors, while having a septic tank as a sanitary facility represented a protective factor for S. stercoralis exposure in indigenous persons. None of the variables evaluated were associated with S. stercoralis exposure in the professional group. The study herein has reported a high seroprevalence to Strongyloides stercoralis in indigenous communities of Brazil and healthcare professionals, warning for potential public health concerns of strongyloidiasis in such populations.
  • article 0 Citação(ões) na Scopus
    Immunoreactivity of proteins within 30-40 kDa range during the acute and the recovery phases in rats experimentally infected with Strongyloides venezuelensis
    (2020) FONSECA, Priscilla Duarte Marques; CORRAL, Marcelo Andreeta; MEISEL, Dirce Mary C. Lima; LEVI, Debora; NASCIMENTO, Rafael Correa; CASTRO-BORGES, William; GRYSCHEK, Ronaldo; COSTA-CRUZ, Julia Maria; PAULA, Fabiana Martins de
    In experimental infection with Strongyloides venezuelensis, the acute and recovery phases can be distinguished, unlike human infections caused by Strongyloides stercoralis. The objective of this study was to evaluate the production of anti-Strongyloides IgG antibodies and the recognition of immunogenic protein bands during the acute and the recovery phases in rats experimentally infected with S. venezuelensis. Rats were infected subcutaneously with 400 or 4,000 S. venezuelensis infective larvae. The acute phase was characterized by elimination of a large number of eggs in the faeces on days 6-14 post infection; the recovery phase was characterized by the resolution of the infection between days 30 and 35 post infection. Differences in IgG levels were observed in the acute and the recovery phases. Different antigenic fractions were recognized in both phases of infection. It is concluded that proteins within the 30-40 kDa range are immunoreactive markers for both the acute and the recovery phases in rats experimentally infected with S. venezuelensis, particularly using membrane antigen.
  • article 13 Citação(ões) na Scopus
    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 Borges
    Strongyloides 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.
  • article 15 Citação(ões) na Scopus
    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 Paulo
    Strongyloidiasis 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.
  • article 5 Citação(ões) na Scopus
    Shotgun proteomics of Strongyloides venezuelensis infective third stage larvae: Insights into host-parasite interaction and novel targets for diagnostics
    (2020) FONSECA, Priscilla D. M.; CORRAL, Marcelo A.; COSENZA-CONTRERAS, Miguel; MEISEL, Dirce M. C. L.; MELO, Gessica B.; ANTUNES, Milena M. S.; SANTO, Maria C. E.; GRYSCHEK, Ronaldo C. B.; COSTA-CRUZ, Julia M.; CASTRO-BORGES, William; PAULA, Fabiana M.
    Strongyloides venezuelensis is an important alternative source of antigen for the serologic diagnosis of human strongyloidiasis. Proteomics techniques applied to the analysis of the protein content of infective third stage larvae (iL3) of S. venezuelensis provide a powerful tool for the discovery of new candidates for immunodiagnosis. This study presents an overview of the protein iL3 S. venezuelensis focusing on the diagnosis of strongyloidiasis. A total of 877 proteins were identified by shotgun proteomics. Many of these proteins are involved in different cellular processes, metabolic as well as structural maintenance. Our results point to a catalog of possible diagnostic targets for human strongyloidiasis and highlight the need for evaluation of uncharacterized proteins, especially the proteins within the CAP domain, transthyretin, and BTPI inhibitor domains, as a repertoire as yet unexplored in the context of strongyloidiasis diagnostic markers. We believe that the protein profile presented in this shotgun analysis extends our understanding of the protein composition within the Strongyloides genus, opening up new perspectives for research on biomarkers that may help with the diagnosis of human strongyloidiasis. Data are available via ProteomeXchange with identifier PXD013703.
  • article 0 Citação(ões) na Scopus
    Shotgun proteomics of Strongyloides venezuelensis infective third stage larvae: Insights into host-parasite interaction and novel targets for diagnostic (vol 235, 111249, 2020)
    (2020) FONSECA, Priscilla D. M.; CORRAL, Marcelo A.; COSENZA-CONTRERAS, Miguel; MEISEL, Dirce M. C. L.; MELO, Gessica B.; ANTUNES, Milena M. S.; SANTO, Maria C. E.; GRYSCHEK, Ronaldo C. B.; COSTA-CRUZ, Julia M.; CASTRO-BORGES, William; PAULA, Fabiana M.
  • article 0 Citação(ões) na Scopus
    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 Zevallos
    The 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.
  • article 12 Citação(ões) na Scopus
    Screening of Strongyloides infection using an ELISA test in transplant candidates
    (2019) TOLEDO, Beatriz; CORRAL, Marcelo A.; MEISEL, Dirce Mary C. L.; GOTTARDI, Maiara; ABDALA, Edson; COSTA, Silvia F.; PIERROTTI, Ligia Camera; LESCANO, Susana A. Z.; GONCALVES, Elenice M. N.; CASTILHO, Vera L. P.; CHIEFFI, Pedro P.; GRYSCHEK, Ronaldo C. B.; PAULA, Fabiana M.
    OBJECTIVES: Hyperinfection or disseminated strongyloidiasis has been frequently reported after transplants and is related to high mortality. This study aimed to screen for strongyloidiasis using serological diagnoses in transplant candidates. METHODS: An ELISA test was performed with filariform larvae of Strongyloides venezuelensis as a source of antigen. RESULTS: In the serum from transplant candidates, anti-Strongyloides IgG antibodies were detected in 35/150 (23.3%) samples by soluble fractions in phosphate buffered saline (PBS), 31/150 (20.7%) samples by soluble fractions in Tris-HCl, 27/150 (18.0%) samples by membrane fractions in PBS and 22/150 (14.7%) samples by membrane fractions in Tris-HCl. CONCLUSIONS: The present results suggest the ELISA test, ideally using soluble fractions of filariform larvae S. venezuelensis in PBS, as an additional strategy for the diagnosis of strongyloidiasis in transplant candidates.