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Featured researches published by Dennis Armando Bertolini.


Journal of Clinical Microbiology | 2004

Hepatitis B Virus Genotypes and Precore and Core Mutants in Brazilian Patients

Roberta Sitnik; João Renato Rebello Pinho; Dennis Armando Bertolini; Antonio Plinio Bernardini; Luiz Caetano da Silva; Flair José Carrilho

ABSTRACT A method for genotyping hepatitis B virus by partial HBsAg gene sequencing with primers common to all known genotypes was developed. Mutations related to anti-HBs resistance are also detected with this method. Samples from 103 Brazilian patients were analyzed. Precore and core region of these viruses were also sequenced in 101 patients. Genotypes A, B, C, D, and F were found with frequencies of 49.5, 2.9, 13.6, 24.3, and 9.7%, respectively. Genotypes B and C were found only in Asian patients, whereas genotypes A, D, and F were more common in patients without an Asian background. Precore mutants were found in 32 (31.7%) of 101 patients, with a higher frequency in those infected with genotype D (22 of 25 [88.0%]). Analysis of nucleotide 1858 showed presence of thymine in all patients with genotypes B, C, and D and in a few patients with genotypes A (10.0%) and F (30.0%), who showed more frequently the presence of cytosine. This nucleotide was closely related to the presence of precore mutants. Mutations in the basal core promoter were found in 64 of 101 (63.4%) samples. These mutations were more frequent in patients infected with genotype F (90.0%) and less frequent in patients infected with genotype B (33.3%). Deletions in this region were found in two genotype C-infected patients.


BMC Public Health | 2004

Hepatitis B virus infection in Haemodialysis Centres from Santa Catarina State, Southern Brazil. Predictive risk factors for infection and molecular epidemiology

Flair José Carrilho; Cleusa R de Moraes; J.R.R. Pinho; Isabel Mello; Dennis Armando Bertolini; Marcílio Figueiredo Lemos; Regina Célia Moreira; Leda Bassit; Rita Helena Antonelli Cardoso; Gabriela Ribeiro-dos-Santos; Luiz Caetano da Silva

BackgroundPatients under haemodialysis are considered at high risk to acquire hepatitis B virus (HBV) infection. Since few data are reported from Brazil, our aim was to assess the frequency and risk factors for HBV infection in haemodialysis patients from 22 Dialysis Centres from Santa Catarina State, south of Brazil.MethodsThis study includes 813 patients, 149 haemodialysis workers and 772 healthy controls matched by sex and age. Serum samples were assayed for HBV markers and viraemia was detected by nested PCR. HBV was genotyped by partial S gene sequencing. Univariate and multivariate statistical analyses with stepwise logistic regression analysis were carried out to analyse the relationship between HBV infection and the characteristics of patients and their Dialysis Units.ResultsFrequency of HBV infection was 10.0%, 2.7% and 2.7% among patients, haemodialysis workers and controls, respectively. Amidst patients, the most frequent HBV genotypes were A (30.6%), D (57.1%) and F (12.2%). Univariate analysis showed association between HBV infection and total time in haemodialysis, type of dialysis equipment, hygiene and sterilization of equipment, number of times reusing the dialysis lines and filters, number of patients per care-worker and current HCV infection. The logistic regression model showed that total time in haemodialysis, number of times of reusing the dialysis lines and filters, and number of patients per worker were significantly related to HBV infection.ConclusionsFrequency of HBV infection among haemodialysis patients at Santa Catarina state is very high. The most frequent HBV genotypes were A, D and F. The risk for a patient to become HBV positive increase 1.47 times each month of haemodialysis; 1.96 times if the dialysis unit reuses the lines and filters ≥ 10 times compared with haemodialysis units which reuse < 10 times; 3.42 times if the number of patients per worker is more than five. Sequence similarity among the HBV S gene from isolates of different patients pointed out to nosocomial transmission.


Revista Da Sociedade Brasileira De Medicina Tropical | 1999

Observações sobre o diagnóstico laboratorial e a epidemiologia da leishmaniose tegumentar no Estado do Paraná, sul do Brasil

Thaís Gomes Verzignassi Silveira; Sandra Mara Alessi Aristides Arraes; Dennis Armando Bertolini; Ueslei Teodoro; Maria Valdrinez Campana Lonardoni; Andréa Claudia Bekner Silva Roberto; Miria Ramos; Antonio Nerilo Sobrinho; Edna Ishikawa; Jeffrey J. Shaw

Between 1986 and 1997 a total of 1418 patients were examined at the Clinical Analysis Teaching and Research Laboratory of Maringa State University (LEPAC/UEM) for cutaneous leishmaniasis by direct examination of stained smears made from the lesions, the Montenegro skin test and the indirect immunofluorescent antibody test. Nine hundred and fifty five patients (67.3%) were positive for at least one of the three tests and of these 804 (84.2%) were considered to have contracted the disease in Parana State; 665 (69.6%) were between 15 and 49 years old; 658 (68.9%) were males; 523 (54.8%) sought medical advice during the first three months of their infections and 74 (7.7%) had mucosal lesions. Of the 83 counties of Parana State, where the patients had most probably acquired their infections, 44.7% were from the counties of Sao Jorge do Ivai (10.2%), Doutor Camargo (9.8%), Terra Boa (7.3%), Maringa (7.3%), Jussara (6.0%) and Cianorte (4.5%). Seventy seven strains of Leishmania (Viannia) braziliensis were isolated and 63.6% of these strains belong to serodema 1.Between 1986 and 1997 a total of 1418 patients were examined at the Clinical Analysis Teaching and Research Laboratory of Maringá State University (LEPAC/UEM) for cutaneous leishmaniasis by direct examination of stained smears made from the lesions, the Montenegro skin test and the indirect immunofluorescent antibody test. Nine hundred and fifty five patients (67.3%) were positive for at least one of the three tests and of these 804 (84.2%) were considered to have contracted the disease in Paraná State; 665 (69.6%) were between 15 and 49 years old; 658 (68.9%) were males; 523 (54.8%) sought medical advice during the first three months of their infections and 74 (7.7%) had mucosal lesions. Of the 83 counties of Paraná State, where the patients had most probably acquired their infections, 44.7% were from the counties of São Jorge do Ivaí (10.2%), Doutor Camargo (9.8%), Terra Boa (7.3%), Maringá (7.3%), Jussara (6.0%) and Cianorte (4.5%). Seventy seven strains of Leishmania (Viannia) braziliensis were isolated and 63.6% of these strains belong to serodema 1.


Cadernos De Saude Publica | 1996

Aspectos epidemiológicos da leishmaniose tegumentar em área endêmica do Estado do Paraná, Brasil

Thaís Gomes Verzignassi Silveira; Ueslei Teodoro; Maria Valdrinez Campana Lonardoni; Ana Lúcia Falavigna Guilherme; Max Jean Ornelas de Toledo; Miria Ramos; Sandra Mara Alessi Aristides Arraes; Dennis Armando Bertolini; Roberto Palma Spinoza; Orlando Carlos Barbosa

Realizou-se em 1992 e 1993 um inquerito epidemiologico para leishmaniose tegumentar (LT) envolvendo 684 individuos de uma populacao de aproximadamente 1400 pessoas de seis localidades agricolas (Fazenda Palmital, Cerâmica Andira, Fazenda Jussara, Fazenda Lagoa, Destilaria Melhoramentos e Fazenda Murure) de uma area endemica nos Municipios de Jussara e Terra Boa, no Norte do Estado do Parana, Brasil. Do total de 684 individuos estudados, 19,9% tinham historia de LT. Ressalta-se que na Fazenda Jussara ocorreu o maior percentual de pessoas com historia de LT (51/126 ou 40,5%). Das 684 reacoes de imunofluorescencia indireta realizadas, 58 (8,5%) tiveram titulos significativos, e destas, 17 (29,3%) eram de pessoas sem historia de LT. A intradermorreacao de Montenegro foi realizada em 97 individuos com historia de LT, sendo positiva em 80 (82,5%) deles. No momento do inquerito, sete individuos apresentavam lesao caracteristica de LT, e em quatro deles a pesquisa de Leishmania sp. foi positiva. A cepa de Leishmania isolada de um destes individuos foi identificada como Leishmania (Viannia) braziliensis.


Brazilian Journal of Medical and Biological Research | 2006

Prevalence of serological markers of hepatitis B virus in pregnant women from Paraná State, Brazil

Dennis Armando Bertolini; J.R.R. Pinho; Cláudia Patara Saraceni; Regina Célia Moreira; Celso Francisco Hernandes Granato; Flair José Carrilho

The prevalence of hepatitis B virus (HBV) in Brazil increases from South to North but moderate to elevated prevalence has been detected in the Southwest of Paraná State. The prevalence of serological markers of HBV was evaluated in 3188 pregnant women from different counties in Paraná State and relevant epidemiological features were described. The prevalence of HBV markers in pregnant women for the state as a whole was 18.5% (95% CI = 17.2-19.9), ranging from 7.2% in Curitiba to 38.5% in Francisco Beltrão. The endemicity of HBV marker prevalence in pregnant women was intermediate in Cascavel, Foz do Iguaçu, and Francisco Beltrão, and low in Curitiba, Londrina, Maringá, and Paranaguá. Multiple logistic regression showed that HBV marker prevalence increased with age, was higher among black women, among women of Italian and German descent, and among women who had family members in neighboring Rio Grande do Sul State. Univariate analysis showed that HBV marker prevalence was also higher among women with no education or only primary education, with a lower family income and whose families originated from the South Region of Brazil. Pregnant women not having positive HBV markers (anti-HBc, HBsAg or anti-HBs detected by ELISA) corresponded to 73.7% of the population studied, implying that HBV vaccination needs to be reinforced in Paraná State. The highest prevalence was found in three counties that received the largest number of families from Santa Catarina and Rio Grande do Sul, where most immigrants were of German or Italian ascendance. This finding probably indicates that immigrants that came to this area brought HBV infection to Southwestern Paraná State.


Revista De Saude Publica | 1993

Nota sobre leishmaniose canina no noroeste do Estado do Paraná, sul do Brasil

Maria Valdrinez Camapana Lonardoni; Ueslei Teodoro; Sandra Mara Alessi Aristides Arraes; Thaís Gomes Verzignassi Silveira; Dennis Armando Bertolini; Edna Ishikawa; Jeffrey J. Shaw

Em area endemica de leishmaniose tegumentar americana no Municipio de Jussara, Estado do Parana, Brasil, detectaram-se tres caes domesticos infectados por Leishmania (Viannia) brasiliensis.Em area endemica de leishmaniose tegumentar americana no Municipio de Jussara, Estado do Parana, Brasil, detectaram-se tres caes domesticos infectados por Leishmania (Viannia) brasiliensis.


Cadernos De Saude Publica | 1996

Investigação sorológica em cães de área endêmica de leishmaniose tegumentar, no Estado do Paraná, Sul do Brasil

Thaís Gomes Verzignassi Silveira; Ueslei Teodoro; Maria Valdrinez Campana Lonardoni; Max Jean Ornelas de Toledo; Dennis Armando Bertolini; Sandra Mara Alessi Aristides Arraes; Dirceu Vedovello Filho

Increased reporting of mucocutaneous leishmaniasis in the State of Paraná points to the need for information on both this diseases epidemiology and pertinent control measures. A serological survey was thus performed, with indirect immunofluorescence (IIF) for canine leishmaniasis in farm operations belonging to the Companhia Melhoramentos Norte do Paraná, in Jussara and Terra Boa counties, in northwestern Paraná. IIF was performed on 132 dogs, of which 24 (18.2%) had significant titers (>/=40). Imprints of six dogs with lesions were made and all were negative for Leishmania sp.


Infection, Genetics and Evolution | 2012

Hepatitis B virus genotypes from European origin explains the high endemicity found in some areas from southern Brazil

Dennis Armando Bertolini; Michele Soares Gomes-Gouvêa; Isabel Maria Vicente Guedes de Carvalho-Mello; Cláudia Patara Saraceni; Roberta Sitnik; Felipe Gobbi Grazziotin; Jomar Pereira Laurindo; Nelson Jurandi Rosa Fagundes; Flair José Carrilho; João Renato Rebello Pinho

Southern Brazil is considered an area of low Hepatitis B endemicity, but some areas of higher endemicity have been described in the Southwest of Paraná and Santa Catarina states. The aim of this study was to evaluate viral genotypes circulating throughout Paraná state. PCR amplification and partial sequencing of the S gene was carried out in 228 samples from HBsAg positive candidate blood donors. Samples have been collected in seven different counties (Cascavel, Curitiba, Foz do Iguaçu, Francisco Beltrão, Maringá, Londrina and Paranaguá). The most common HBV genotype in Paraná state was D (82.9%; 189/228), followed by A (14.1%; 32/228). Genotypes F (1.3%; 3/228), C (1.3%; 3/228) and H (0.4%; 1/228) were also found. Distribution of genotypes was different in the studied counties, but genotype D was the most frequent in all of them. In Francisco Beltrão, all studied samples belonged to genotype D. The high prevalence of HBV genotype D in South of Brazil is explained by the intense migration of settlers from Europeans countries. Subgenotypes A1 and A2 were identified circulating in all cities where HBV/A was found. As observed in other areas of Brazil, HBV/A1 is more frequent than the HBV/A2 in Paraná state and its presence was significantly larger in black and mulatto individuals. Genotype C was found only in individuals with Asian ancestry from Londrina and Maringá. Most HBV/F sequences identified in this study were classified as subgenotype F2a that was previously described in Brazil. The sole case of subgenotype F4 was from Foz do Iguaçu city, near to Northern Argentina, where F4 is highly prevalent. The single genotype H sample was from Curitiba. This is the first case of this genotype described in Brazil. Further studies should be carried out to determine if more genotype H samples can be found in other populations from Brazil.


Revista Brasileira de Ginecologia e Obstetrícia | 2013

Prevalence of positive sorology for HIV, hepatitis B, toxoplasmosis and rubella in pregnant women from the northwestern region of the state of Paraná

Rafael Isolani Ferezin; Dennis Armando Bertolini; Izabel Galhardo Demarchi

PURPOSE To ascertain the seroprevalence of human immunodeficiency virus (HIV), hepatitis B (HBV), toxoplasmosis and rubella infections in pregnant women in northwestern Paraná. METHODS We conducted a retrospective study based on the results of serological screening during prenatal care of 1,534 patients during the first half of 2010. We included only results from the first prenatal exam and with a simultaneous search for IgG and IgM antibodies to rubella and toxoplasmosis. Serology was performed by microparticle enzyme immunoassay (MEIA). Data were analyzed statistically by the χ² test, with the level of significance set at 5%. RESULTS HIV positivity was 0.3%, positivity of HBV serology (HbsAg) was 0.5%, reactivity to IgM antibodies to Toxoplasma gondii was 1.1%, and reactivity to IgG antibodies was 59.0%. For rubella, no patient was positive for IgM, and IgG reactivity was 99.6%. Data analysis showed no statistical association between seroprevalence and patient age, except for the frequency of anti-T. gondii IgG, which was higher in the 30 to 44 year age group. CONCLUSION The prevalence of these infectious diseases in pregnant women from northwestern Paraná is comparable to that observed in other regions of Brazil.


Antiviral Therapy | 2015

HBV carrying drug-resistance mutations in chronically infected treatment-naive patients.

Michele Soares Gomes-Gouvêa; Ariana C. Ferreira; Rosangela Teixeira; Jose R. Andrade; Adalgisa de Souza Paiva Ferreira; Lena Maria Barros; Rosamar Eulira Fontes Rezende; Ana C. S. Santos Nastri; A.G. Leite; Leonora Z Piccoli; Josiane Galvan; Simone Regina Sousa da Silva Conde; Manoel do Carmo Pereira Soares; Dimas A. Kliemann; Dennis Armando Bertolini; Aline S. O. Kunyoshi; André Castro Lyra; Marcio K. Oikawa; Luciano Vieira de Araújo; Flair José Carrilho; Maria Cássia Jacintho Mendes-Correa; João Renato Rebello Pinho

BACKGROUND Nucleoside/nucleotide analogue (NA) treatment causes selection pressure for HBV strains carrying mutations conferring NA resistance. Drug-resistance mutations occur in the reverse transcriptase (RT) region of the HBV polymerase gene and spontaneously arise during viral replication. These mutations can also alter the hepatitis B surface (HBs) protein and in some cases reduce binding to HBs antibodies. The spread of NA-resistant HBV may impact the efficacy of antiviral treatment and hepatitis B immunization programmes. In this study, we used direct sequencing to assess the occurrence of HBV carrying known mutations that confer NA resistance in the largest cohort of treatment-naive patients with chronic hepatitis B (CHB) to date. METHODS HBV DNA samples isolated from 702 patients were sequenced and the RT region subjected to mutational analysis. RESULTS There was high genetic variability among the HBV samples analysed: A1 (63.7%), D3 (14.5%), A2 (3.3%), A3 (0.1%), B1 (0.1%), B2 (0.1%), C2 (0.9%), D1 (0.9%), D2 (4.6%), D4 (5.1%), D unclassified subgenotype (0.7%), E (0.6%), F2a (4.6%), F4 (0.4%) and G (0.4%). HBV strains harbouring mutations conferring NA resistance alone or combined with compensatory mutations were identified in 1.6% (11/702) of the patients. CONCLUSIONS HBV strains harbouring resistance mutations can comprise the major population of HBV quasispecies in treatment-naive patients. In Brazil, there is a very low frequency of untreated patients who are infected with these strains. These findings suggest that the spread and natural selection of drug-resistant HBV is an uncommon event and/or most of these strains remain unstable in the absence of NA selective pressure.

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Claudinei Mesquita da Silva

Universidade Estadual de Maringá

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Leyde Daiane de Peder

State University of West Paraná

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Eraldo Schunk Silva

Universidade Estadual de Maringá

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Miria Ramos

Universidade Estadual de Maringá

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