Duffy blood group gene polymorphisms among malaria vivax patients in four areas of the Brazilian Amazon region

Background: Duffy blood group polymorphisms are important in areas where Plasmodium vivax predominates, because this molecule acts as a receptor for this protozoan. In the present study, Duffy blood group genotyping in P. vivax malaria patients from four different Brazilian endemic areas is reported, exploring significant associations between blood group variants and susceptibility or resistance to malaria.Methods: the P. vivax identification was determined by non-genotypic and genotypic screening tests. The Duffy blood group was genotyped by PCR/RFLP in 330 blood donors and 312 malaria patients from four Brazilian Amazon areas. In order to assess the variables significance and to obtain independence among the proportions, the Fisher's exact test was used.Results: the data show a high frequency of the FYA/FYB genotype, followed by FYB/FYB, FYA/FYA, FYA/FYB-33 and FYB/FYB-33. Low frequencies were detected for the FYA/FY(X), FYB/FY(X), FYX/FY(X) and FYB-33/FYB-33 genotypes. Negative Duffy genotype (FYB-33/FYB-33) was found in both groups: individuals infected and non-infected (blood donors). No individual carried the FY(X)/FYB-33 genotype. Some of the Duffy genotypes frequencies showed significant differences between donors and malaria patients.Conclusion: the obtained data suggest that individuals with the FYA/FYB genotype have higher susceptibility to malaria. The presence of the FYB-33 allele may be a selective advantage in the population, reducing the rate of infection by P. vivax in this region. Additional efforts may contribute to better elucidate the physiopathologic differences in this parasite/host relationship in regions endemic for P. vivax malaria, in particular the Brazilian Amazon region.

Observational study on efficacy of negative expiratory pressure test proposed as screening for obstructive sleep apnea syndrome among commercial interstate bus drivers - protocol study

Background: Obstructive sleep apnea (OSA) is a respiratory disease characterized by the collapse of the extrathoracic airway and has important social implications related to accidents and cardiovascular risk. The main objective of the present study was to investigate whether the drop in expiratory flow and the volume expired in 0.2 s during the application of negative expiratory pressure (NEP) are associated with the presence and severity of OSA in a population of professional interstate bus drivers who travel medium and long distances.Methods/Design: An observational, analytic study will be carried out involving adult male subjects of an interstate bus company. Those who agree to participate will undergo a detailed patient history, physical examination involving determination of blood pressure, anthropometric data, circumference measurements (hips, waist and neck), tonsils and Mallampati index. Moreover, specific questionnaires addressing sleep apnea and excessive daytime sleepiness will be administered. Data acquisition will be completely anonymous. Following the medical examination, the participants will perform a spirometry, NEP test and standard overnight polysomnography. The NEP test is performed through the administration of negative pressure at the mouth during expiration. This is a practical test performed while awake and requires little cooperation from the subject. In the absence of expiratory flow limitation, the increase in the pressure gradient between the alveoli and open upper airway caused by NEP results in an increase in expiratory flow.Discussion: Despite the abundance of scientific evidence, OSA is still underdiagnosed in the general population. In addition, diagnostic procedures are expensive, and predictive criteria are still unsatisfactory. Because increased upper airway collapsibility is one of the main determinants of OSA, the response to the application of NEP could be a predictor of this disorder. With the enrollment of this study protocol, the expectation is to encounter predictive NEP values for different degrees of OSA in order to contribute toward an early diagnosis of this condition and reduce its impact and complications among commercial interstate bus drivers.

An improved electrophoretic method for a screening program for haemoglobinopathies

A method for a screening program for haemoglobinopathies in a starch agar gel mixed with saponin is presented. Normal and abnormal blood containing haemoglobins S, C, I, M Boston, D Punjab, beta thalassaemia major and beta thalassaemia minor, were applied, in a tray with the capacity for 100 samples. The electrophoresis was performed in 45 min using 300 V. This method offers special advantages for the examination of a large number of samples, using a small amount of whole blood and without the previous preparation of haemoglobin solution.

Resting heart rate: Its correlations and potential for screening metabolic dysfunctions in adolescents

Background: In pediatric populations, the use of resting heart rate as a health index remains unclear, mainly in epidemiological settings. The aims of this study were to analyze the impact of resting heart rate on screening dyslipidemia and high blood glucose and also to identify its significance in pediatric populations.Methods: The sample was composed of 971 randomly selected adolescents aged 11 to 17 years (410 boys and 561 girls). Resting heart rate was measured with oscillometric devices using two types of cuffs according to the arm circumference. Biochemical parameters triglycerides, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and glucose were measured. Body fatness, sleep, smoking, alcohol consumption and cardiorespiratory fitness were analyzed.Results: Resting heart rate was positively related to higher sleep quality (β = 0.005, p = 0.039) and negatively related to cardiorespiratory fitness (β = -0.207, p = 0.001). The receiver operating characteristic curve indicated significant potential for resting heart rate in the screening of adolescents at increased values of fasting glucose (area under curve = 0.611 ± 0.039 [0.534 - 0.688]) and triglycerides (area under curve = 0.618 ± 0.044 [0.531 - 0.705]).Conclusion: High resting heart rate constitutes a significant and independent risk related to dyslipidemia and high blood glucose in pediatric populations. Sleep and cardiorespiratory fitness are two important determinants of the resting heart rate. © 2013 Fernandes et al.; licensee BioMed Central Ltd.

A contribuição do voto de autoexclusão na segurança transfusional

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

Detection of HTLV-IIa in blood donors in an urban area of the Amazon Region of Brazil (Belém, PA)

Os vírus linfotrópicos de células T humanas tipo I (HTLV-I) e tipo II (HTLV-II) são membros de um grupo de retrovírus de mamíferos com propriedades biológicas similares que apresentam como uma das principais rotas de transmissão a transfusão sangüínea. O HTLV-I é endêmico em diferentes áreas geográficas e está associado a vários distúrbios clínicos. O HTLV-II é endêmico em vários grupos indígenas das Américas e em usuários de drogas intravenosas na América do Norte e do Sul, Europa e Sudeste da Ásia. Durante o ano de 1995, todos os doadores de sangue positivos para HTLV-I/II no Banco de Sangue do Estado (HEMOPA), foram direcionados a um médico e ao Laboratório de Virologia na Universidade Federal do Pará, para consulta, aconselhamento e confirmação do diagnóstico laboratorial. Trinta e cinco soros foram testados por um ensaio imunoenzimático e confirmados por um Western blot que discrimina as infecções por HTLV-I e HTLV-II. Amostras soropositivas para HTLV-II foram submetidas à reação em cadeia da polimerase (PCR) para as regiões genômicas env e pX e confirmaram ser do subtipo IIa. Esta é a primeira detecção, em Belém, da presença da infecção pelo HTLV-IIa em doadores de sangue. Estes resultados enfatizam que o HTLV-II está presente em áreas urbanas da região Amazônica e a necessidade de incluir testes de triagem capazes de detectar anticorpos para ambos os tipos de HTLV.

Molecular detection of Treponema pallidum sp. pallidum in blood samples of VDRL-seroreactive women with lethal pregnancy outcomes: a retrospective observational study in northern Brazi

INTRODUÇÃO: Apesar das medidas de controle da sífilis materna e congênita estarem disponíveis no Brasil, existem dificuldades da rede em prover o diagnóstico laboratorial da infecção durante o pré-natal. O objetivo deste estudo foi confirmar a presença do Treponema pallidum pela PCR em mulheres com sorologia positiva ao VDRL e com resultado letal da gravidez, isto é, aborto, natimorto e neomorto. MÉTODOS: Estudo retrospectivo realizado em mulheres VDRL-sororeativas com resultado negativo da gravidez, admitidas na Fundação Santa Casa de Misericórdia do Pará FSCM-PA entre janeiro e julho de 2004. As amostras de soro e DNA de sangue total foram obtidas no mesmo período da triagem pelo VDRL. Estas amostras foram analisadas pelo ELISA IgG, FTA-Abs IgM e PCR simples (polA). RESULTADOS: Durante o período de estudo, 0,7% (36/4.912) das mulheres com resultado letal da gravidez apresentaram VDRL positivo. O genepolA foi amplificado em 72,7% (24/33) destas mulheres,com 55,6% (20/36) e 94,4% (34/36) apresentando anticorpos tipo IgG e IgM contra o T. pallidum, respectivamente. A comparação destes resultados mostrou uma diferença estatística significativa, sendo que os resultados da PCR versus FTA-Abs Ig Mmostraram-se concordantes, sugerindo que a sífilis materna era uma infecção ativa. A causa básica de morte dos conceptos não foi relatada em 97,2% (35/36) dos casos. Entre as mulheres que foram submetidas ao VDRL no pré-natal, somente quatro das nove soropositivas receberam tratamento. CONCLUSÕES: A elevada frequência de sífilis no grupo de estudo indica a fragilidade do serviço no diagnóstico, tratamento e monitoramento da infecção, comprometendo o controle epidemiológico.

Soroepidemiologia do HCV em doadores de sangue na cidade de Imperatriz – MA

Devido à alta mortalidade e, principalmente, a morbidade, as hepatites são um dos mais graves problemas de Saúde Pública, no País e no mundo. Entre elas destacamos a infecção da hepatite C. O número de pessoas que desconhecem que são portadoras do vírus HCV é relevante. Como atualmente a transmissão do HCV por transfusão sanguínea e hemoderivados é rara entre os doadores de sangue, depois da introdução do método de triagem nos centros hemoterápicos, fundamental para detectar a existência de uma possível infecção neste doador. A realidade epidemiológica da hepatite C em Imperatriz necessita de maior conhecimento e planejamento das estratégias de prevenção e assistência aos portadores de HCV, uma vez que não existe uma rede de serviço consolidada para o tratamento, a burocracia é grande para se chegar ao diagnóstico da doença e a sub-notificação dos casos é elevada. Tem como objetivo avaliar a soroprevalência do HCV em candidatos à doação de sangue no município de Imperatriz – MA; assim como analisar o perfil dos candidatos considerados inaptos a doação de sangue no HEMOMAR, nesta cidade; determinar a soroprevalência do Vírus da Hepatite C entre os doadores de sangue no período de 2005 a 2010; realizar o levantamento dos dados epidemiológicos, destacando o gênero e a faixa etária de maior prevalência do vírus da hepatite C; comparar os dados epidemiológicos identificando a procedência dos candidatos soropositivos para o vírus da hepatite C. o estudo é de caráter descritivo transversal, envolvendo doadores de sangue do Centro de Hematologia e Hemoterapia do Estado do Maranhão de Imperatriz - MA. Na distribuição dos doadores de sangue do HEMOMAR, regional de Imperatriz -MA quanto ao sexo, constata-se que, nos anos de 2005 à 2011 o fluxo de doadores caracterizou-se por indivíduos de ambos os sexos,com predominância do masculino (75,01%), quando analisamos o perfil dos candidatos a doadores com sorologia positiva para HCV, observamos que estes também eram a maioria. A faixa etária dos doadores de sangue do HEMOMAR predominante era de 18-29. Os candidatos a doação com sorologia positiva para HCV, foram encontrados 79,17% na situação de casados/união estável. Entre os doadores que foram considerados inaptos a doação, 0,21% apresentou sorologia positiva para HCV. A maioria dos candidatos a doadores com soropositividade para HCV pertencia ao município de Imperatriz. Concluiu-se que é importante lembrar que o processo de triagem clínica e laboratorial diminui riscos de contaminação no processo de transfusão sanguínea. A figura do doador de sangue deve ser sempre valorizada e parabenizada por todos.

Genomic screening of testicular germ cell tumors from monozygotic twins

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

In vivo evaluation of the genetic toxicity of Rubus niveus Thunb. (Rosaceae) extract and initial screening of its potential chemoprevention against doxorubicin-induced DNA damage

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Aloimunização de doadores de sangue como fonte de anti-soros e hemácias raras

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

Vasovagal reactions in whole blood donors at three REDS-II blood centers in Brazil

BACKGROUND: In Brazil little is known about adverse reactions during donation and the donor characteristics that may be associated with such events. Donors are offered snacks and fluids before donating and are required to consume a light meal after donation. For these reasons the frequency of reactions may be different than those observed in other countries. STUDY DESIGN AND METHODS: A cross-sectional study was conducted of eligible whole blood donors at three large blood centers located in Brazil between July 2007 and December 2009. Vasovagal reactions (VVRs) along with donor demographic and biometric data were collected. Reactions were defined as any presyncopal or syncopal event during the donation process. Multivariable logistic regression was performed to identify predictors of VVRs. RESULTS: Of 724,861 donor presentations, 16,129 (2.2%) VVRs were recorded. Rates varied substantially between the three centers: 53, 290, and 381 per 10,000 donations in Recife, Sao Paulo, and Belo Horizonte, respectively. Although the reaction rates varied, the donor characteristics associated with VVRs were similar (younger age [18-29 years], replacement donors, first-time donors, low estimated blood volume [EBV]). In multivariable analysis controlling for differences between the donor populations in each city younger age, first-time donor status, and lower EBV were the factors most associated with reactions. CONCLUSION: Factors associated with VVRs in other locations are also evident in Brazil. The difference in VVR rates between the three centers might be due to different procedures for identifying and reporting the reactions. Potential interventions to reduce the risk of reactions in Brazil should be considered.

Antimicrobial activity of two techniques for arm skin disinfection of blood donors in Brazil

Objective: Evaluation of the antimicrobial effect of skin disinfection techniques is essential to avoid the transmission of infectious agents during blood transfusion. The aim of this study was to examine the effectiveness of two methods of arm skin disinfection used in blood donors at a Hemotherapy Center in Brazil that represents an important centre for distributing haemocomponents to many cities in the country. Methods: Two skin disinfection techniques in 50 blood donors were evaluated. For the first arm, 10% povidone-iodine/two-stage technique was used. On the opposite arm, 0.5% chlorhexidine digluconate alcohol solution/one-stage technique was used. The swabs were seeded on three culture media: blood agar, mannitol salt agar and Mac Conkey agar. Automated bacterial classification based on biochemical tests/specific substrates was performed. Donor characteristics were collected using the computerised system of the Hemotherapy Center. Results: We found that microbial reduction was significantly higher for 10% povidone-iodine technique (98.57-98.87%) when compared with 0.5% chlorhexidine technique (94.38-95.06%). The species Leuconostoc mesenteroides and Staphylococcus hominis showed resistance to both disinfection techniques. We did not find statistically significant relationships between donor characteristics and microbial reduction. Conclusions: Arm skin disinfection with 10% povidone-iodine produced better antimicrobial activity. We must acknowledge that 10% povidone-iodine technique has the limitation of being a two-stage method. However, prevention of adverse events due to bacterial contamination and transfusion reactions should be prioritised. Production of hypoallergenic and stronger antiseptics that allowed a safe one-stage disinfection technique should be encouraged in health systems, not only in Brazil but also around the world.

Prevalence of celiac disease among blood donors in Sao Paulo - the most populated city in Brazil

OBJECTIVE: Celiac disease is a permanent enteropathy caused by the ingestion of gluten, which leads to an immune-mediated inflammation of the small intestine mucosa. The prevalence of celiac disease varies among different nations and ethnic backgrounds, and its diversity is determined by genetic and environmental factors. Sao Paulo city is one of the largest cities in the world, with a vast population and an important history of internal migratory flow from other Brazilian regions, as well as immigration from other, primarily European, countries, resulting in significant miscegenation. The aim of the present study was to estimate the prevalence of adults with undiagnosed celiac disease among blood donors of Sao Paulo by collecting information on the ancestry of the population studied. METHODS: The prevalence of celiac disease was assessed by screening for positive IgA transglutaminase and IgA endomysium antibodies in 4,000 donors (volunteers) in the Fundacao Pro-Sangue Blood Center of Sao Paulo, Sao Paulo, Brazil. The antibody-positive subjects were asked to undergo a small bowel biopsy. RESULTS: Of the 4,000 subjects, twenty-four had positive tests, although both antibody tests were not always concordant. For example, ten subjects were positive for IgA tissue transglutaminase only. In twenty-one positive patients, duodenal biopsies were performed, and the diagnosis of celiac disease was confirmed in fourteen patients (Marsh criteria modified by Oberhuber). In this group, 67% claimed to have European ancestry, mainly from Italy, Portugal and Spain. CONCLUSION: The prevalence of celiac disease is at least 1: 286 among supposedly healthy blood bank volunteers in Sao Paulo, Brazil.

Recipient of kidney from donor with asymptomatic infection by Paracoccidioides brasiliensis

The increase in solid organ transplantations may soon create a rise in the occurrence of endemic fungal diseases, such as paracoccidioidomycosis, due to the lack of rigorous screening of donors from endemic areas. Here we present the first case of an immunocompetent and asymptomatic kidney donor who had Paracoccidioides brasiliensis infected-adrenal tissue but no glandular dysfunction.