122 research outputs found

    Identification of Streptococcus pneumoniae by a real-time PCR assay targeting SP2020.

    Get PDF
    Real-time PCR targeting lytA (the major autolysin gene) and piaB (permease gene of the pia ABC transporter) are currently used as the gold-standard culture-independent assays for Streptococcus pneumoniae identification. We evaluated the performance of a new real-time PCR assay - targeting SP2020 (putative transcriptional regulator gene) - and compared its performance with the assays previously described. A collection of 150 pneumococci, 433 non-pneumococci and 240 polymicrobial samples (obtained from nasopharynx, oropharynx, and saliva; 80 from each site) was tested. SP2020 and lytA-CDC assays had the best performance (sensitivity of 100% for each compared to 95.3% for piaB). The specificity for lytA and piaB was 99.5% and for SP2020 was 99.8%. Misidentifications occurred for the three genes: lytA, piaB and SP2020 were found in non-pneumococcal strains; piaB was absent in some pneumococci including a serotype 6B strain. Combining lytA and SP2020 assays resulted in no misidentifications. Most polymicrobial samples (88.8%) yielded concordant results for the three molecular targets. The remaining samples seemed to contain non-typeable pneumococci (0.8%), and non-pneumococci positive for lytA (1.7%) or SP2020 (8.7%). We propose that combined detection of both lytA-CDC and SP2020 is a powerful strategy for the identification of pneumococcus either in pure cultures or in polymicrobial samples

    Experimental Plasmodium vivax infection of key Anopheles species from the Brazilian Amazon

    Get PDF
    Made available in DSpace on 2015-09-21T17:25:38Z (GMT). No. of bitstreams: 2 license.txt: 1914 bytes, checksum: 7d48279ffeed55da8dfe2f8e81f3b81f (MD5) jose_lima_etal_IOC_2013.pdf: 530553 bytes, checksum: ecc989c032bd9da39e398d263e88b3ae (MD5) Previous issue date: 2013Fundação Oswaldo Cruz. Instituto Leônidas e Maria Deane. Manaus, AM, Brasil / Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, Brasil.Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil / Universidade do Estado do Amazonas. Manaus, AM, Brasil.Instituto Nacional de Pesquisas da Amazônia, Manaus, AM, Brasil / Universidade do Estado do Amazonas. Manaus, AM, Brasil. / Ministerio da Saúde. Núcleo Amazonas. Fundação de Vigilância em Saúde. Manaus, AM, Brasil.Universidade Federal de Mato Grosso. Cuiabá, MT, Brasil.Instituto Nacional de Pesquisas da Amazônia. Manaus, AM, Brasil.Fundação Oswaldo Cruz. Instituto Leônidas e Maria Deane. Manaus, AM, Brasil.Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil / Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil.Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil / Universidade do Estado do Amazonas. Manaus, AM, Brasil.Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, Brasil.Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil / Universidade do Estado do Amazonas. Manaus, AM, Brasil.Instituto Nacional de Pesquisas da Amazônia. Manaus, AM, Brasil.Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Manaus, AM, Brasil / Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou; Belo Horizonte, MG, Brasil.Background: Anopheles darlingi is the major malaria vector in countries located in the Amazon region. Anopheles aquasalis and Anopheles albitarsis s.l. are also proven vectors in this region. Anopheles nuneztovari s.l. and Anopheles triannulatus s.l. were found infected with Plasmodium vivax; however, their status as vectors is not yet well defined. Knowledge of susceptibility of Amazon anopheline populations to Plasmodium infection is necessary to better understand their vector capacity. Laboratory colonization of An. darlingi, the main Amazon vector, has proven to be difficult and presently An. aquasalis is the only available autonomous colony. Methods: Larvae of An. darlingi, An. albitarsis s.l., An. nuneztovari s.l. and An. triannulatus s.l. were collected in the field and reared until adult stage. Adults of An. aquasalis were obtained from a well-established colony. Mosquitoes were blood-fed using a membrane-feeding device containing infected blood from malarial patients. The infection of the distinct Anopheles species was evaluated by the impact variance of the following parameters: (a) parasitaemia density; (b) blood serum inactivation of the infective bloodmeal; (c) influence of gametocyte number on infection rates and number of oocysts. The goal of this work was to compare the susceptibility to P. vivax of four field-collected Anopheles species with colonized An. aquasalis. Results: All Anopheles species tested were susceptible to P. vivax infection, nevertheless the proportion of infected mosquitoes and the infection intensity measured by oocyst number varied significantly among species. Inactivation of the blood serum prior to mosquito feeding increased infection rates in An. darlingi and An. triannulatus s.l., but was diminished in An. albitarsis s.l. and An. aquasalis. There was a positive correlation between gametocyte density and the infection rate in all tests (Z = −8.37; p < 0.001) but varied among the mosquito species. Anopheles albitarsis s.l., An. aquasalis and An. nuneztovari s.l. had higher infection rates than An. darlingi. Conclusion: All field-collected Anopheles species, as well as colonized An. aquasalis are susceptible to experimental P. vivax infections by membrane feeding assays. Anopheles darlingi, An. albitarsis s.l. and An. aquasalis are very susceptible to P. vivax infection. However, colonized An. aquasalis mosquitoes showed the higher infection intensity represented by infection rate and oocyst numbers. This study is the first to characterize experimental development of Plasmodium infections in Amazon Anopheles vectors and also to endorse that P. vivax infection of colonized An. aquasalis is a feasible laboratory model

    Factors Associated with Height Catch-Up and Catch-Down Growth Among Schoolchildren

    Get PDF
    In developed countries, children with intrauterine growth restriction (IUGR) or born preterm (PT) tend to achieve catch-up growth. There is little information about height catch-up in developing countries and about height catch-down in both developed and developing countries. We studied the effect of IUGR and PT birth on height catch-up and catch-down growth of children from two cohorts of liveborn singletons. Data from 1,463 children was collected at birth and at school age in Ribeirão Preto (RP), a more developed city, and in São Luís (SL), a less developed city. A change in z-score between schoolchild height z-score and birth length z-score≥0.67 was considered catch-up; a change in z-score≤−0.67 indicated catch-down growth. The explanatory variables were: appropriate weight for gestational age/PT birth in four categories: term children without IUGR (normal), IUGR only (term with IUGR), PT only (preterm without IUGR) and preterm with IUGR; infant's sex; maternal parity, age, schooling and marital status; occupation of family head; family income and neonatal ponderal index (PI). The risk ratio for catch-up and catch-down was estimated by multinomial logistic regression for each city. In RP, preterms without IUGR (RR = 4.13) and thin children (PI<10th percentile, RR = 14.39) had a higher risk of catch-down; catch-up was higher among terms with IUGR (RR = 5.53), preterms with IUGR (RR = 5.36) and children born to primiparous mothers (RR = 1.83). In SL, catch-down was higher among preterms without IUGR (RR = 5.19), girls (RR = 1.52) and children from low-income families (RR = 2.74); the lowest risk of catch-down (RR = 0.27) and the highest risk of catch-up (RR = 3.77) were observed among terms with IUGR. In both cities, terms with IUGR presented height catch-up growth whereas preterms with IUGR only had height catch-up growth in the more affluent setting. Preterms without IUGR presented height catch-down growth, suggesting that a better socioeconomic situation facilitates height catch-up and prevents height catch-down growth

    A efetividade do laser de HeNe 632,8 nm no reestabelecimento da integridade dos tecidos cutâneos em animais experimentais: revisão sistemática

    Get PDF
    O objetivo desta revisão sistemática foi analisar o efeito do laser de HeNe na cicatrização de feridas em ratos. Foram selecionados estudos experimentais que adotaram o laser HeNe para o tratamento de feridas agudas em ratos adultos saudáveis, com lesões induzidas por bisturi, nas bases de dados PubMed/MEDLINE, LILACS e SciELO. Foram utilizados os seguintes descritores: cicatrização de feridas e colágeno, de acordo com o MeSH e o DeCS, além dos unitermos laser HeNe e reparação da pele e seus equivalentes em inglês e espanhol. Três estudos foram incluídos na revisão sistemática, não sendo possível a realização de metanálise, devido à impossibilidade de comparação entre as metodologias dos estudos selecionados. Todos os estudos realizaram análise por meio de cortes histológicos das cicatrizes. A presença de falhas metodológicas nos três artigos dificultou a interpretação fidedigna dos dados encontrados. Os estudos destacaram uma redução na intensidade da resposta inflamatória e uma melhor organização das fibras colágenas no grupo irradiado. A terapia com laser HeNe mostrou boa resposta no reparo tecidual. No entanto, tais resultados devem ser analisados de modo criterioso, uma vez que há presença de heterogeneidade, principalmente em relação aos parâmetros adotados

    Prevalence of non-communicable diseases in Brazilian children: follow-up at school age of two Brazilian birth cohorts of the 1990's

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Few cohort studies have been conducted in low and middle-income countries to investigate non-communicable diseases among school-aged children. This article aims to describe the methodology of two birth cohorts, started in 1994 in Ribeirão Preto (RP), a more developed city, and in 1997/98 in São Luís (SL), a less developed town.</p> <p>Methods</p> <p>Prevalences of some non-communicable diseases during the first follow-up of these cohorts were estimated and compared. Data on singleton live births were obtained at birth (2858 in RP and 2443 in SL). The follow-up at school age was conducted in RP in 2004/05, when the children were 9-11 years old and in SL in 2005/06, when the children were 7-9 years old. Follow-up rates were 68.7% in RP (790 included) and 72.7% in SL (673 participants). The groups of low (<2500 g) and high (≥ 4250 g) birthweight were oversampled and estimates were corrected by weighting.</p> <p>Results</p> <p>In the more developed city there was a higher percentage of non-nutritive sucking habits (69.1% vs 47.9%), lifetime bottle use (89.6% vs 68.3%), higher prevalence of primary headache in the last 15 days (27.9% vs 13.0%), higher positive skin tests for allergens (44.3% vs 25.3%) and higher prevalence of overweight (18.2% vs 3.6%), obesity (9.5% vs 1.8%) and hypertension (10.9% vs 4.6%). In the less developed city there was a larger percentage of children with below average cognitive function (28.9% vs 12.2%), mental health problems (47.4% vs 38.4%), depression (21.6% vs 6.0%) and underweight (5.8% vs 3.6%). There was no difference in the prevalence of bruxism, recurrent abdominal pain, asthma and bronchial hyperresponsiveness between cities.</p> <p>Conclusions</p> <p>Some non-communicable diseases were highly prevalent, especially in the more developed city. Some high rates suggest that the burden of non-communicable diseases will be high in the future, especially mental health problems.</p
    • …
    corecore