RONALDO CESAR BORGES GRYSCHEK

(Fonte: Lattes)
Índice h a partir de 2011
12
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

Resultados de Busca

Agora exibindo 1 - 7 de 7
  • 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 1 Citação(ões) na Scopus
    Management and treatment of decompensated hepatic fibrosis and severe refractory Schistosoma mansoni ascites with transjugular intrahepatic portosystemic shunt
    (2022) SANTO, Maria Cristina Carvalho do Espirito; GRYSCHEK, Ronaldo Cesar Borges; FARIAS, Alberto Queiroz; ANDRAUS, Wellington; CARVALHO, Noemia Barbosa; LEITE, Olavo Henrique Munhoz; CASTRO, Felipe Correa; CERRI, Giovanni Guido; HYPOLITTI, Gustavo Henrique; CARNEVALE, Francisco Cesar; ASSIS, Andre Moreira de
    This study aimed to report the first case of a patient with hepatosplenic schistosomiasis mansoni, refractory ascites and portal vein thrombosis treated with a transjugular intrahepatic portosystemic shunt (TIPS), at the Instituto de Radiologia, Hospital das Clinicas, Faculdade de Medicina, Universidade de Sao Paulo, Brazil. After the procedure, the patient recovered favorably and progressed with portal pressure reduction and no deterioration of the liver function. Endovascular shunt modification is a conservative medical approach that often helps in reducing symptoms significantly, making it a less invasive and a safer alternative to liver transplantation for the treatment of schistosomiasis with portal hypertension.
  • article 2 Citação(ões) na Scopus
    Prevalence and Associated Factors of Cryptococcal Antigenemia in HIV-Infected Patients with CD4 < 200 Cells/mu L in Sao Paulo, Brazil: A Bayesian Analysis
    (2022) MIMICOS, Evanthia Vetos; FOSSALUZA, Victor; PICONE, Camila de Melo; SENA, Camila Caroline de; GOMES, Helio Rodrigues; LAZARI, Carolina dos Santos; SILVA, Fernanda Ferreira da; NAKANISHI, Erika Shimoda; NISIDA, Isabelle Vichr; FREITAS, Angela Carvalho; GRYSCHEK, Ronaldo Borges; LAGONEGRO, Eduardo Ronner; LAZERA, Marcia; SHIKANAI-YASUDA, Maria Aparecida
    Cryptococcosis is a severe life-threatening disease and a major cause of mortality in people with advanced AIDS and CD4 <= 100 cells/ mu L. Considering the knowledge gap regarding the benefits of routine application of antigenemia tests in HIV-infected patients with 100-200 CD4 cells/mu L for the prevention of cryptococcal meningitis (CM), we aimed to evaluate the prevalence of positive antigenemia through lateral flow assay (LFA) and associated factors in HIV-infected patients with CD4 < 200 cells/ mu L. Our findings of 3.49% of positive LFA (LFA+) patients with CD4 < 100 cells/mu L and 2.24% with CD4 between 100-200 cells/mu L have been included in a Bayesian analysis with 12 other studies containing similar samples worldwide. This analysis showed a proportion of 3.6% LFA+ patients (95% credible interval-Ci [2.5-5.7%]) with CD4 < 100 cells/mu L and 1.1% (95%Ci [0.5-4.3%]) with CD4 between 100-200 cells/mu L, without statistical difference between these groups. The difference between mortality rates in LFA+ and negative LFA groups was e = 0.05013. Cryptococcoma and CM were observed in the LFA+ group with 100-200 and <100 CD4 cells/mu L, respectively. Considering the benefits of antifungal therapy for LFA+ patients, our data reinforced the recommendation to apply LFA as a routine test in patients with 100-200 CD4 cells/ mu L aiming to expand cost-effectiveness studies in this group.
  • article 1 Citação(ões) na Scopus
    Importance of detection of Strongyloides stercoralis DNA in fecal samples from patients with type 2 diabetes mellitus
    (2022) MAZZARO, Marcia Carolina; SANTOS, Emelin Alves dos; MELO, Gessica Baptista de; MARQUES, Priscila Duarte; SOUZA, Laura Vilela; ELIAS-OLIVEIRA, Jefferson; SILVA, Bruna Campos da; GRYSCHEK, Ronaldo Cesar Borges; PAULA, Fabiana Martins de; RODRIGUES, Rosangela Maria
    Objective: The association between diabetes and Strongyloides infection remains controversial. This study aimed to detect Strongyloides stercoralis DNA in the feces of patients with Diabetes Mellitus type 2 (DM2). Methods: Fecal samples were analyzed via the Lutz, Rugai, and agar plate culture methods. PCR amplification was performed using two targets (PCR-genus and PCR-species) located on the S. stercoralis 18S ribosomal. Results: The positivity for S. stercoralis using parasitological methods was 1.1%. PCR-genus (14.13%) demonstrated a higher positivity than PCR-species (9.78%). Conclusion: The results confirm the greater positivity of the molecular diagnosis in relation to parasitological methods, reinforcing its use as an additional tool for the diagnosis of S. stercoralis infection in patients with DM2 living in endemic areas for this helminthiasis.
  • article 2 Citação(ões) na Scopus
    Serological diagnosis of strongyloidiasis in immunocompetent and immunosuppressed patients based on an electrochemical immunoassay using a flexible device allied to PLS-DA and ROC statistical tools
    (2022) MATTOS, Gabriel J.; MARCHEAFAVE, Gustavo G.; ROLDAN, William H.; MATTOS, Miguel J.; PAULA, Fabiana M. de; GRYSCHEK, Ronaldo C. B.; SARTORI, Elen R.
    Strongyloidiasis is a tropical disease caused by the nematode called Strongyloides stercoralis. An electrochemical immunosensor was efficiently constructed for the diagnosis of this helminthiasis using the larvae epicuticle as the antigen electrostatically immobilized on the surface of a screen-printed electrode, modified with graphene/ ZnOQDs composite. The mechanism of monitoring was based on the changes in the electrochemical parameters of the device due to the antigen-antibody binding on its interface. The immunosensor was characterized using electrochemical impedance spectroscopy and cyclic voltammetry, evaluating the impedimetric/voltammetric biorecognition of the antigen-antibody complex using the redox group K4Fe(CN)6 as the electrochemical probe. This bioelectronic device detected antibodies in positive serum samples based on the voltammetric profile and electrochemical impedance monitoring. Partial least squares-discriminant analysis showed a coefficient of determination of 0.98, indicating that the model can correctly classify samples as positive or negative for strongyloidiasis, based on the voltammetric profile of samples from immunocompetent patients. The analysis of the root mean square error of cross-validation (0.126), the root mean square error of calibration (0.124), and the root mean square error of prediction (0.100) for the latent variable indicate the optimal precision of the model. Based on the receiver operating characteristic curves, the cutoff was determined for the electrochemical impedance measurements, obtaining a 100% correct classification for immunocompetent patients and just 1.25% false-negatives in cases of immunosuppressed patients. The immunosensor presented excellent specificity in the presence of other helminthiases, including ascaridiasis, diphyllobothriasis, himenolepiasis, cysticercosis, and trichuriasis.
  • article 0 Citação(ões) na Scopus
    Immune complexes as a tool for strongyloidiasis immunodiagnosis in kidney and liver transplant candidate
    (2022) CORRAL, Marcelo A.; GONCALVES, Ana Lucia R.; COSTA, Idessania N.; ABDALA, Edson; PIERROTTI, Ligia C.; CHIEFFI, Pedro Paulo; COSTA-CRUZ, Julia Maria; GRYSCHEK, Ronaldo Cesar B.; PAULA, Fabiana Martins
    Strongyloidiasis is a chronic and asymptomatic infection in immunocompetent patients. Immunocompromised patients, such as organ transplant candidates, can develop severe forms of this disease, and the best way to prevent progression to these forms is early diagnosis. Serological techniques using specific IgG and immune complexes (IC) detection can help in the diagnosis of these patients. This study aimed to detect specific anti-Strongyloides IC and IgG antibodies in kidney transplant (KT) and liver transplant (LT) candidates. A total of 100 blood samples was collected from transplant candidates (50 blood samples each from KT and LT candidates). Serum was obtained and analysed using enzyme-linked immunosorbent assay for IC and IgG detections. The IC levels showed frequencies of 18% and 2% in the KT and LT groups, respectively, whereas anti-Strongyloides IgG was detected in 34% and 12% of KT and LT candidates, respectively. The correlation between IC and IgG detection is poor in KT candidates, while in LT candidates, there is a significant positive correlation. The detection of IC can be an additional tool for the diagnosis of strongyloidiasis, especially when associated with the detection of specific IgG anti-Strongyloides antibodies.
  • article 1 Citação(ões) na Scopus
    Proteomic analysis of the excretory-secretory products from Strongyloides venezuelensis infective larvae: new insights for the immunodiagnosis of human strongyloidiasis
    (2022) GONZALES, William Henry Roldan; COELHO, Guilherme Rabelo; PIMENTA, Daniel Carvalho; PAULA, Fabiana Martins de; GRYSCHEK, Ronaldo Cesar Borges
    Serodiagnosis of human strongyloidiasis is a practical alternative to parasitological methods due to its high sensitivity. However, cross-reactivity with other helminth infections limits its utility, and this problem is due to the use of homologous or heterologous somatic extracts of the parasite as an antigen source. Excretory-secretory (E/S) products from Strongyloides infective larvae can be used to improve the serodiagnosis. The combined use of western blot and proteomics became an interesting strategy to identify immunological markers for the serodiagnosis of strongyloidiasis. The present study describes the proteomic analysis of the antigenic components from E/S products of S. venezuelensis infective larvae that were recognized by IgG antibodies from patients with strongyloidiasis. Our results showed that IgG antibodies from patients with strongyloidiasis recognized between 15 and 16 antigenic bands in the E/S products from S. venezuelensis that were incubated in PBS or in RPMI culture medium, respectively. Overall, antigenic bands of low and high molecular weight were more specific than those of intermediate molecular weight, which were cross-reactive. A 36-kDa antigenic band was 93% sensitive and 100% specific (a probably arginine kinase of 37 kDa), while other antigenic bands were highly sensitive but low specific. Proteomic analysis revealed differences between the protein profiles from E/S-RPMI and E/S-PBS since only one-third of all proteins identified were common in both types of E/S products. Bioinformatic analysis showed that more than 50% of the proteins from E/S products are secreted within extracellular vesicles and only a small percentage of them are actually released by the classical secretory pathway. Several components from the E/S products were identified as plasminogenbinding proteins, probably used as an immune evasion mechanism. The data provided here provide valuable information to increase understanding of E/S products from S. venezuelensis infective larvae. This may help us to find new targets for the immunodiagnosis of human strongyloidiasis.