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
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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- 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 BorgesTo 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.
- 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 WelkerAuthor 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.
- Twenty years of successful academic outreach at Nucleo de Medicina Tropical (NACE-NUMETROP/USP) in Santarem, Para(2021) SAID, Renato do Carmo; ASSY, Joao Guilherme Pontes Lima; SILVA, Kamila Vieira; BRANDAO, Alisson dos Santos; PINHEIRO, Olivia Campos; ESPER, Helena Rangel; GRYSCHEK, Anna Luiza de Fatima Pinho Lins; BERTOLOZZI, Maria Rita; AMATO, Valdir Sabbaga; BOULOS, Marcos; SEGURADO, Aluisio Augusto Cotrim; GRYSCHEK, Ronaldo Cesar Borges; FRANCA, Francisco Oscar de Siqueira
- 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 deIn 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.
conferenceObject DETECTION OF SCHISTOSOMA MANSONI SPOROCYST STAGE IN BIOMPHALARIA GLABRATA MOLLUSK IN EXPERIMENTAL CONDITIONS(2018) CASOTTI, Marcia; TUAN, Roseli; GOMES, Michele; LUNA, Expedito Albuquerque; DIAS-NETO, Emmanuel; PAULA, Fabiana; PINHO, Joao Rebello; CARRILHO, Flair; GRYSCHEK, Ronaldo Borges; ESPIRITO-SANTO, MariabookPart Estrongiloidíase Disseminada(2013) GRYSCHEK, Ronaldo Cesar Borges- 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.
conferenceObject MOLECULAR CHARACTERIZATION OF THE LARVAL PHASE OF SCHISTOSOMA MANSONI IN BIOMPHALARIA GLABRATA MOLLUSKS UNDER EXPERIMENTAL CONDITIONS(2017) CASOTTI, Marcia Oliveira; TUAN, Roseli Tuan; GOMES, Michele; DIAS-NETO, Emmanuel; PINHO, Joao Renato Rebello; PAULA, Fabiana Martins; CARRILHO, Flair Jose Carrilho Jose; LUNA, Expedito Jose Albuquerque; GRYSCHEK, Ronaldo Cesar Borges Borges; ESPIRITO-SANTO, Maria Cristina- TWO SEQUENTIAL PCR AMPLIFICATIONS FOR DETECTION OF Schistosoma mansoni IN STOOL SAMPLES WITH LOW PARASITE LOAD(2012) ESPIRITO-SANTO, Maria Cristina Carvalho do; ALVARADO-MORA, Monica Viviana; PINTO, Pedro Luiz Silva; CARRILHO, Flair Jose; PINHO, Joao Renato Rebello; GRYSCHEK, Ronaldo Cesar BorgesSchistosomiasis constitutes a major public health problem, with an estimated 200 million individuals infected worldwide and 700 million people living in risk areas. In Brazil there are areas of high, medium and low endemicity. Studies have shown that in endemic areas with a low prevalence of Schistosoma infection the sensitivity of parasitological methods is clearly reduced. Consequently diagnosis is often impeded due to the presence of false-negative results. The aim of this study is to present the PCR reamplification (Re-PCR) protocol for the detection of Schistosoma mansoni in samples with low parasite load (with less than 100 eggs per gram (epg) of feces). Three methods were used for the lysis of the envelopes of the S. mansoni eggs and two techniques of DNA extraction were carried out. Extracted DNA was quantified, and the results suggested that the extraction technique, which mixed glass beads with a guanidine isothiocyanate/phenol/chloroform (GT) solution, produced good results. PCR reamplification was conducted and detection sensitivity was found to be five eggs per 500 mg of artificially marked feces. The results achieved using these methods suggest that they are potentially viable for the detection of Schistosoma infection with low parasite load.