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Dive into the research topics where Norival Kesper is active.

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Featured researches published by Norival Kesper.


Acta Tropica | 2014

New insights about cross-reactive epitopes of six trypanosomatid genera revealed that Crithidia and Leptomonas have antigenic similarity to L. (L.) chagasi

Leandro Rodrigues Ferreira; Norival Kesper; Marta M. G. Teixeira; Márcia Dalastra Laurenti; Clara Lúcia Barbiéri; José Angelo Lauletta Lindoso; Eufrosina S. Umezawa

We investigated whether ELISA using crude antigens from insect and plant trypanosomatids, which are non-pathogenic and easily cultivated in large scale, has the same positivity data as Leishmania (Leishmania) chagasi, the etiological agent of human visceral leishmaniasis (VL) or canine leishmaniasis (CanL), or as Trypanosoma cruzi, the etiological agent of Chagas disease (CD). The antigens from Crithidia fasciculata, Crithidia luciliae, and Leptomonas seymouri showed 100% cross-reactivity with VL and CanL samples, with no statistically titers differences from L. (L.) chagasi, however, 34% (17/50) of VL samples revealed higher titers using the insect trypanosomatids than the homologous antigen. On the other hand, antigens from Strigomonas culicis, Angomonas deanei, and Phytomonas serpens showed low cross-reactivity with VL and CanL samples. The sera from patients with American tegumentary leishmaniasis showed low levels of cross-reactivity with all trypanosomatids investigated, even with L. (L) chagasi, without titers dissimilarity among them. These parasites were also worthless as antigen source for detection of CD cases, which required homologous antigens to reach 100% positivity. This study showed, by ELISA, that crude extract of Crithidia and Leptomonas have epitopes similar to L. (L.) chagasi, which supports the idea of using them as antigens source for the serodiagnosis of visceral leishmaniasis.


Revista Brasileira De Parasitologia Veterinaria | 2013

Canine visceral leishmaniasis and Chagas disease among dogs in Araguaína, Tocantins

Arielle Nunes Morais; Marlos Gonçalves Sousa; Luciana Regina Meireles; Norival Kesper; Eufrosina S. Umezawa

The present study analyzed serum samples from 111 male and female dogs of various ages from the municipality of Araguaína in the State of Tocantins, Brazil. Serological diagnosis of canine visceral leishmaniasis (CVL) was initially performed at the Central Laboratory (Laboratório Central - LACEN) of Araguaína, resulting in 61 positive samples by an indirect immunofluorescence assay (IIFA) (≥1:40) and 50 non-reactive samples. The same samples were analyzed at the São Paulo Institute of Tropical Medicine (Instituto de Medicina Tropical de São Paulo - IMTSP) by an enzyme-linked-immunosorbent assay (ELISA), resulting in 57 positive samples (51.35%) and 54 negative samples (48.64%). The Kappa coefficient of agreement between the tests was 0.74. The serum samples were also subjected to a diagnostic assay for Trypanosoma cruzi (Trypomastigote Excreted/Secreted Antigens -TESA-blot) that detected five suspect animals; three of those animals were positive for leishmaniasis by ELISA but negative by IIFA. These findings suggest that the canine population of Araguaína may be simultaneously infected with Leishmania chagasi and T. cruzi. The results obtained demonstrate the difficulty of using serology to detect CVL, thus emphasizing the necessity for a reference test to diagnose CVL, particularly in regions where the infection is endemic.


American Journal of Tropical Medicine and Hygiene | 2013

The Efficacy of L. (L.) chagasi Excreted-Secreted Antigens (ESAs) for Visceral Leishmaniasis Diagnosis Is Due To Low Levels of Cross-Reactivity

Viviana Pinedo-Cancino; Norival Kesper; Clara Lúcia Barbiéri; José Angelo Lauletta Lindoso; Eufrosina S. Umezawa

The analysis of promastigote excreted-secreted antigen (ESA) reactivity with 53 visceral leishmaniasis (VL) cases showed that each sample reacted regardless of the antigen or the Leishmania species used in enzyme-linked immunosorbent assay (ELISA) displayed 100% positivity with the L. (L.) chagasi ESA-blot recognizing bands of molecular weight ranging from 26.5 to 31.5 kDa. The analysis of 160 non-visceral cases showed that 5% of the samples cross-reacted with the L. (L.) chagasi ESA-ELISA and 9.4% reacted with the ESA isolated from L. (L.) amazonensis and L. (V.) braziliensis, whereas a high cross-reaction ranging from 24.4% to 25% was observed with total crude promastigote antigens (PRO-ELISA). The ESA-blot of L. (L.) chagasi tested with non-visceral sera samples showed a cross-reaction with 8.8% of cases; most of these cases represented tegumentary leishmaniasis and only one acute chagasic case. These data lead us to recommend the use of ESA as an alternative antigen in VL diagnosis.


Acta Tropica | 2016

Evaluation of Leishmania (Leishmania) infantum excreted-secreted antigens for detection of canine leishmaniasis

Viviana Pinedo-Cancino; Márcia Dalastra Laurenti; Norival Kesper; Eufrosina S. Umezawa

The efficacy of tests with L. (L.) infantum excreted-secreted antigens (ESA) to detect canine leishmaniasis (CanL) was evaluated using immunoblotting (ESA-blot), ELISA (ESA-ELISA) and ELISA with alkaline extract from promastigotes (PAE). Of one hundred fifty-five domestic dogs tested, 100 were suspected of CanL, 23 had other diseases and 32 were healthy. Sera from the dogs suspected of CanL were tested by immunohistochemistry (IHC), and 54% were confirmed to be infected by L. (L.) infantum (38 symptomatic and 16 asymptomatic). Of these, 100% were positive by ESA-blot, ESA-ELISA and PAE-ELISA. In the ESA-blot their sera recognized polypeptides in the 26.5-31.5kDa region. Of the 46% of dogs with negative IHC, 44-53% tested positive in all three tests irrespective of clinical status. The twenty-three dogs with other diseases were negative by ESA-blot, but sera from 9% and 26% of them reacted with ESA-ELISA and PAE-ELISA, respectively. The 32 healthy dogs were negative in all the tests. ESA-blot showed good correlation with IHC in the detection of CanL and a high specificity index.


American Journal of Tropical Medicine and Hygiene | 2012

Profile of Trypanosoma cruzi Reactivity in a Population at High Risk for Endemic Pemphigus Foliaceus (Fogo Selvagem)

Joaquim X. Sousa; Luis A. Diaz; Donald P. Eaton; Gunter Hans-Filho; Elder Lanzani Freitas; Livia Delgado; Ligia Maria F. Ichimura; Flávia Cristaldi; Renata Orlandi; Norival Kesper; Eufrosina S. Umezawa; Evandro A. Rivitti; Valeria Aoki

Fogo selvagem (FS) is an autoimmune bullous disease with pathogenic IgG autoantibodies recognizing desmoglein 1 (Dsg1), a desmosomal glycoprotein. In certain settlements of Brazil, a high prevalence of FS (3%) is reported, suggesting environmental factors as triggers of the autoimmune response. Healthy individuals from endemic areas recognize nonpathogenic epitopes of Dsg1, and exposure to hematophagous insects is a risk factor for FS. Fogo selvagem and Chagas disease share some geographic sites, and anti-Dsg1 has been detected in Chagas patients. Indeterminate Chagas disease was identified in a Brazilian Amerindian population of high risk for FS. In counterpart, none of the FS patients living in the same geographic region showed reactivity against Trypanosoma cruzi. The profile of anti-Dsg1 antibodies showed positive results in 15 of 40 FS sera and in 33 of 150 sera from healthy individuals from endemic FS sites, and no cross-reactivity between Chagas disease and FS was observed.


International Journal of Primatology | 2017

Infectious Diseases in Free-Ranging Blonde Capuchins, Sapajus flavius, in Brazil

Marina Galvão Bueno; José Luiz Catão-Dias; Plautino de Oliveira Laroque; Silvio Arruda Vasconcellos; José Soares Ferreira Neto; Solange Maria Gennari; Fernando Ferreira; Márcia Dalastra Laurenti; Eufrosina S. Umezawa; Norival Kesper; Karin Kirchgatter; Lilian de Oliveira Guimarães; Heloise Julião Pavanato; Mônica M. Valença-Montenegro

The main threats to primates worldwide are the degradation, fragmentation, and loss of their habitats; hunting (especially for bushmeat); and illegal trade. For many species, the most important threat is forest fragmentation, resulting in small populations that are restricted to isolated forest patches. In this situation, primates are particularly vulnerable to disease. The Endangered blonde capuchin (Sapajus flavius) is now restricted to a few forest patches in Northeast Brazil. We investigated the occurrence of parasites and bacterial diseases in one of three free-ranging groups of S. flavius in a small forest patch in Paraíba state, Northeast Brazil. We tested for antibodies against Leishmania spp., Trypanosoma cruzi, Toxoplasma gondii, Leptospira spp. (24 strains), and Brucella spp.. We used molecular analysis to detect Plasmodium spp., and evaluated blood smears for the presence of hemoparasites. All individuals tested negative for Leptospira spp. and B. abortus, but 8 of 48 (16%) presented antibodies for both Leishmania spp. and T. cruzi. We identified antibodies to T. gondii in 12% of the individuals tested. Plasmodium brasilianum infection was present in 4% of the individuals tested, and blood smears showed microfilariae parasites in 46% of the individuals tested. The occurrence of these infectious diseases in S. flavius may pose a significant threat in terms of reduced recruitment and poor survival rates, and an understanding of the influence of pathogens is crucial for the management of small populations of primates.


Trends in Tropical Medicine | 2016

Leptomonas seymouri and Crithidia fasciculata exoantigens can discriminate human cases of visceral leishmaniasis from American tegumentary leishmaniasis ones

Norival Kesper; Marta Maria Geraldes Teixeira; José Angelo Lauletta Lindoso; Clara Lúcia Barbiéri; Eufrosina S. Umezawa

ABSTRACT Exoantigens (exo) from Leptomonas seymouri and Crithidia fasciculata were used in an enzyme linked immunosorbent assay (ELISA), showing 100% reactivity with sera from visceral leishmaniasis (VL) cases, and no reactivity with American tegumentary leishmaniasis (ATL) ones. Our results have indicated that these exoantigens can be applied in the discrimination of VL and ATL cases.


Journal of Parasitology | 2000

Immunoblot analysis of trypomastigote excreted-secreted antigens as a tool for the characterization of Trypanosoma cruzi strains and isolates.

Norival Kesper; Katia A. Almeida; Anna Maria S. Stolf; Eufrosina S. Umezawa


Archive | 2013

Canine visceral leishmaniasis and Chagas disease among dogs in Araguaína, Tocantins Leishmaniose visceral canina e doença de Chagas em cães de Araguaína, Tocantins

Arielle Nunes Morais; Marlos Gonçalves Sousa; Luciana Regina Meireles; Norival Kesper; Eufrosina S. Umezawa


Archive | 2013

PINEDO-CANCINO AND OTHERS EFFICACY OF L. (L.) CHAGASI ESAS FOR VISCERAL LEISHMANIASIS DIAGNOSIS The Efficacy of L. (L.) chagasi Excreted-Secreted Antigens (ESAs) for Visceral Leishmaniasis Diagnosis Is Due To Low Levels of Cross-Reactivity

Viviana Pinedo-Cancino; Norival Kesper; Clara Lúcia Barbiéri; José Angelo Lauletta Lindoso; Eufrosina S. Umezawa

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Clara Lúcia Barbiéri

Federal University of São Paulo

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Marlos Gonçalves Sousa

Federal University of Tocantins

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