Low frequency of human papillomavirus detection in prostate tissue from individuals from Northern Brazil

The presence of human papillomavirus (HPV) was evaluated in 65 samples of prostate tumours and six samples of prostates with benign prostatic hyperplasia from individuals from Northern Brazil. We used a highly sensitive test, the Linear Array HPV Genotyping Test, to detect 37 high and low-risk HPV types. In this study, only 3% of tumour samples showed HPV infection. Our findings support the conclusion that, despite the high incidence of HPV infection in the geographic regions studied, HPV was not associated with a higher risk of prostate cancer. To our knowledge, this is the first study evaluating the frequency of HPV detection in prostatic tissue of individuals from Brazil.

Frequency of the Q192R and L55M polymorphisms of the human serum paraoxonase gene (PON1) in ten Amazonian Amerindian tribes

Human serum paraoxonase (PON1) is an esterase associated with high density lipoproteins (HDLs) in the plasma and may confer protection against coronary artery disease. Serum PON1 levels and activity vary widely among individuals and populations of different ethnic groups, such variations appearing to be related to two coding region polymorphisms (L55M and Q192R). Several independent studies have indicated that the polymorphism at codon 192 (the R form) is a significant risk factor for cardiovascular disease in some populations, although this association has not been confirmed in other populations. Given the possible associations of these mutations with heart diseases and the fact that little or nothing is known of their prevalence in Amerindian populations, we investigated the variability of both polymorphisms in ten Amazonian Indian tribes and compared the variation found with that of other Asian populations in which both polymorphisms have been investigated. The results show that the LR haplotype is the most frequent and the MR haplotype is absent in all Amerindians and Asian populations. We also found that South America Amerindians present the highest frequency of the PON1192*R allele (considered a significant risk factor for heart diseases in some populations) of all the Amerindian and Asian populations so far studied.

Allele frequency distributions of six hypervariable loci (D1S80, APOB, D4S43, vW1, F13A and DYS19) in two African-Brazilian communities from the Amazon region

ABSTRACT: The allele frequency distributions of three VNTR (D1S80, APOB and D4S43) and three STR (vW1, F13A1 and DYS19) loci were investigated in two Afro-Brazilian populations from the Amazon: Curiau and Pacoval. Exact tests for population differentiation revealed significant differences in allele frequency between populations only for the D1S80 and APOB loci. A statistically significant deviation from the Hardy-Weinberg equilibrium was observed only in the D1S80 locus of the Pacoval sample. A neighbor-joining tree was constructed based on DA genetic distances of allele frequencies in four Afro-Brazilian populations from the Amazon (Pacoval, Curiau, Trombetas, and Cametá), along with those from Congo, Cameroon, Brazilian Amerindians, and Europeans. This analysis revealed the usefulness of these Amp-FLPs for population studies - African and African-derived populations were closely grouped, and clearly separated from Amerindians and Europeans. Estimates of admixture components based on the gene identity method revealed the prevalence of the African component in both populations studied, amounting to 51% in Pacoval, and to 43% in Curiau. The Amerindian component was also important in both populations (37% in Pacoval, and 24% in Curiau). The European component reached 33% in Curiau.

Frequency of antibodies to Babesia bigemina, B. bovis, Anaplasma marginale, Trypanosoma vivax and Borrelia burdgorferi in cattle from the northeastern region of the state of Pará, Brazil

A babesiose, a anaplasmose e a tripanossomose são enfermidades relevantes, potencialmente causadoras de morbidade em bovinos, levando a perdas econômicas. A borreliose assume importância como zoonose potencial. O objetivo desse estudo foi determinar, por meio do ensaio de imunoadsorção enzimática (ELISA), a freqüência de anticorpos para Babesia bigemina, B. bovis, Anaplasma marginale, Trypanosoma vivax e Borrelia burgdorferi em bovinos da região nordeste do Estado do Pará, Brasil. Amostras de soro de 246 vacas dos municípios de Castanhal e São Miguel do Guamá foram usadas. ELISAs com antígeno bruto foram utilizados para detector anticorpos contra todos os agentes, exceto para A. marginale, para o qual um ELISA indireto com proteína principal de superfície 1a (MSP1a) foi usado. As freqüências de bovinos soropositivos foram: B. bigemina - 99,2%; B. bovis - 98,8%; A. marginale - 68,3%; T. vivax - 93,1% and B. burgdorferi -54,9% As freqüências de bovinos soropositivos para B. bovis e B. bigemina sugerem uma alta taxa de transmissão desses organismos por carrapatos, na região estudada, a qual pode ser classificada com sendo de estabilidade enzoótica para os hemoparasitos. A baixa freqüência de bovinos soropositivos para A. marginale pode ser atribuída a uma menor sensibilidade do ELISA com antígeno recombinante, ou uma menor taxa de inoculação da riquétsia pelos carrapatos, quando comparada àquelas observadas para Babesia sp. A alta freqüência de bovinos soropositivos para T. vivax indica que esse hemoprotozoário é prevalente em rebanhos do nordeste do Estado do Pará. O percentual de animais com anticorpos homólogos para B. burgdorferi indica a presenças deste espiroquetídeo transmitido por carrapatos na população de bovinos da região estudada.

Frequency of paroxysmal nocturnal hemoglobinuria in patients attended in Belém, Pará, Brazil

ABSTRACT: Paroxysmal nocturnal hemoglobinuria is a hematological disease with complex physiopathology. It is genetically characterized by a somatic mutation in the PIG-A gene (phosphatidylinositol glycan anchor biosynthesis, class A), in which the best known antigens are DAF (decay accelerating factor or CD55) and MIRL (membrane inhibitor of reactive lysis or CD59). OBJECTIVE: To determine the frequency of paroxysmal nocturnal hemoglobinuria in patients attended at the HEMOPA foundation from November 2008 to July 2009. METHOD: Thirty patients, with ages ranging from two to 79 years old and suspected of having paroxysmal nocturnal hemoglobinuria were examined. All patients were immunophenotyped by flow cytometry for the CD5, CD59, CD16 and CD45 antigens. RESULTS: Paroxysmal nocturnal hemoglobinuria was identified in nine of the thirty patients investigated. Another 3 cases had inconclusive results with CD59-negative labeling only for neutrophils. The highest frequency of paroxysmal nocturnal hemoglobinuria patients (7/9) and inconclusive cases (2/3) were between 19 years old and 48 years old, with a median of 28 years. CONCLUSION: These results show the importance of flow cytometry to identify cases in which patients are deficient in only one antigen (CD59).

Microwave switchable frequency selective surface with high quality factor resonance and low polarization sensitivity

We present a microwave switchable frequency selective surface with high quality factor transmission resonance. The high quality resonance is achieved by excitation of the trapped-mode in array with two concentric metal rings in a cell on a silicon substrate. Optical activation of the silicon substrate permits to switch off the transmission band.

Exposure to an extremely low-frequency electromagnetic field only slightly modifies the proteome of Chromobacterium violaceum ATCC 12472

Several studies of the physiological responses of different organisms exposed to extremely low-frequency electromagnetic fields (ELF-EMF) have been described. In this work, we report the minimal effects of in situ exposure to ELF-EMF on the global protein expression of Chromobacterium violaceum using a gel-based proteomic approach. The protein expression profile was only slightly altered, with five differentially expressed proteins detected in the exposed cultures; two of these proteins (DNA-binding stress protein, Dps, and alcohol dehydrogenase) were identified by MS/MS. The enhanced expression of Dps possibly helped to prevent physical damage to DNA. Although small, the changes in protein expression observed here were probably beneficial in helping the bacteria to adapt to the stress generated by the electromagnetic field.

Frequency of acute myeloid leukemia in children attended in Belém, Pará from August 2005 to May 2009

Introdução: A leucemia mieloide aguda (LMA) tem incidência variável nas diferentes regiões do Brasil. Objetivos: Determinar a frequência dos subtipos de LMA em crianças entre 0-17 anos, atendidas em Belém, Pará, no período de agosto de 2005 a maio de 2009. Casuística e métodos: Estudo retrospectivo com 278 pacientes com diagnóstico de leucemias agudas ou crônicas com base nos critérios clínicos, morfológicos (classificação franco-americana-britânica [FAB]/Organização Mundial da Saúde [OMS]) e de perfil imunofenotípico por citometria de fluxo para determinação da frequência de subtipos de LMA. Resultados: Foram encontrados 70 (25,18%) casos de LMA; destes, 37 (52,9%) eram crianças entre 0-17 anos (idade mediana de 7 anos e 8 meses). Não houve diferença estatística em relação ao gênero. Observou-se maior frequência de LMA dos subtipos M2 (18/37 - 48,6%) e M0/M1 (10/37 - 27%), principalmente na primeira década de vida (16/28 [57,1%] LMA M2 e 9/28 [32,1%] LMA M0/M1). Conclusão: Na população pediátrica, os tipos de LMA M2, M0/M1 e M3 foram, respectivamente, as mais frequentes.