MAIARA GOTTARDI
Projetos de Pesquisa
Unidades Organizacionais
LIM/59 - Laboratório de Biologia Celular, Hospital das Clínicas, Faculdade de Medicina
9 resultados
Resultados de Busca
Agora exibindo 1 - 9 de 9
- 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.
- Ultrastructural characterization of alveolar microvascular damage in severe COVID-19 respiratory failure(2023) NEGRI, Elnara Marcia; BENCHIMOL, Marlene; MAUAD, Thais; DUARTE-NETO, Amaro Nunes; GOTTARDI, Maiara; SILVA, Luiz Fernando Ferraz da; SALDIVA, Paulo Hilario Nascimento; DOLHNIKOFF, Marisa; SOUZA, Wanderley de; CALDINI, Elia GarciaEndothelial dysfunction is a key phenomenon in COVID-19, induced by direct viral endothelial infection and secondary inflammation, mainly affecting the microvascular circulation. However, few studies described the subcellular aspects of the lung microvasculature and the associated thrombotic phenomena, which are widely present in severe COVID-19 cases. To that end, in this transversal observational study we performed transmission and scanning electron microscopy in nine lung samples of patients who died due to COVID-19, obtained via minimally invasive autopsies in Sao Paulo, Brazil, in 2020. All patients died due to acute respiratory failure and had microvascular thrombosis at histology. Electron microscopy revealed areas of endothelial damage with basal lamina disruption and virus infection in endothelial cells. In the capillary lumens, the ultrastructure of the thrombi is depicted, with red blood cells stacking, dysmorphism and hemolysis, fibrin meshworks, and extracellular traps. Our description illustrates the complex pathophysiology of microvascular thrombosis at the cellular level, which leads to some of the peculiar characteristics of severe COVID-19.
- Immunofluorescence assay for diagnosis of strongyloidiasis in immunocompromised patients(2015) GOTTARDI, Maiara; PAULA, Fabiana M.; CORRAL, Marcelo A.; MEISEL, Dirce Mary C.; COSTA, Silvia F.; ABDALA, Edson; PIERROTTI, Ligia C.; YAMASHIRO, Juliana; CHIEFFI, Pedro Paulo; GRYSCHEK, Ronaldo Cesar B.Background: Strongyloides stercoralis is a parasite that causes human strongyloidiasis. The disease ranges from asymptomatic to severe forms, which are often fatal in immunocompromised individuals. Laboratory diagnosis is challenging owing to limitations in the use of conventional parasitological techniques. The present study aimed to evaluate the indirect immunofluorescence assay (IFA) using infective larvae of S. venezuelensis as an antigen for the immunodiagnosis of human strongyloidiasis in immunocompromised patients. Methods: Serum and stool samples from 200 immunocompromised patients (HIV-positive, HTLV-1-positive, and renal, liver, and/or bone marrow transplantation candidates) were used. Stool samples were examined using three parasitological methods: Lutz, Rugai, and culture agar plate. IFA was performed using sections of infective larvae of S. venezuelensis as antigens, and showed 95.4% sensitivity and 95.8% and specificity. Results: Among the 200 patients, 17 (8.5%) were positive for S. stercoralis by at least one parasitological method, and 43 (21.5%) were positive by IFA. Conclusions: IFA can be used as a screening method for the detection of S. stercoralis in immunocompromised patients.
conferenceObject IMMUNODIAGNOSIS OF STRONGYLOIDES STERCORALIS INFECTION IN CANDIDATE PATIENTS FOR TRANSPLANTATION(2015) GOTTARDI, Maiara; PAULA, Fabiana M.; CORRAL, Marcelo A.; MEISEL, Dirce M.; COSTA, Silvia F.; ABDALA, Edson; PIERROTTI, Ligia; CHIEFFI, Pedro Paulo; GRYSCHEK, Ronaldo C.- 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.