Navegando por Palavras-chave "Molecular diagnosis"
Agora exibindo 1 - 5 de 5
Resultados por página
Opções de Ordenação
- ItemSomente MetadadadosContribution of Molecular Allergen Analysis in Diagnosis of Milk Allergy(Current Medicine Group, 2017) Bartuzi, Zbigniew; Cocco, Renata Rodrigues [UNIFESP]; Muraro, Antonella; Nowak-Wegrzyn, AnnaPurpose of Review We sought to describe the available evidence supporting the utilization of the molecular allergen analysis (MAA) for diagnosis and management of cow milk protein allergy (CMPA). Recent Findings Cow milk proteins are among the most common food allergens in IgE- and non-IgE-mediated food allergic disorders in children. Most individuals with CMPA are sensitized to both caseins and whey proteins. Caseins are more resistant to high temperatures compared to whey proteins. Summary MAA is not superior to the conventional diagnostic tests based on the whole allergen extracts for diagnosis of CMPA. However, MAA can be useful in diagnosing tolerance to extensively heated milk proteins in baked foods. Children with CMPA and high levels of casein IgE are less likely to tolerate baked milk compared to children with low levels of casein IgE. Specific IgE-binding patterns to casein and betalactoglobulin peptides may predict the natural course of CMPA and differentiate subjects who are more likely to develop CMPA at a younger age versus those with a more persistent CMPA. Specific IgE-binding patterns to casein and beta-lactoglobulin peptides may also predict response to milk OIT and identify patients most likely to benefit from OIT.
- ItemSomente MetadadadosPhylogenetic, morphological and behavioural analyses support host switching of Trypanosoma (Herpetosoma) lewisi from domestic rats to primates(Elsevier B.V., 2010-05-01) Silva, F. Maia da; Marcili, A.; Ortiz, P. A.; Epiphanio, S. [UNIFESP]; Campaner, M.; Catao-Dias, J. L.; Shaw, J. J.; Camargo, E. P.; Teixeira, M. M. G.; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)We characterized four Brazilian trypanosomes isolated from domestic rats and three from captive nonhuman primates that were morphologically similar to T. lewisi, a considered non-pathogenic species restricted to rodents and transmitted by fleas, despite its potential pathogenicity for infants. These isolates were identified as T. lewisi by barcoding using V7V8 SSU rDNA sequences. in inferred phylogenetic trees, all isolates clustered tightly with reference T. lewisi and T. lewisi-like trypanosomes from Europe, Asia and Africa and despite their high sequence conservation formed a homogeneous clade separate from other species of the subgenus T. (Herpetosoma). With the aim of clearly resolving the relationships between the Brazilian isolates from domestic rats and primates, we compared sequences from more polymorphic ITS rDNA. Results corroborated that isolates from Brazilian rats and monkeys were indeed of the same species and quite close to T. lewisi isolates of humans and rats from different geographical regions. Morphology of the monkey isolates and their behaviour in culture and in experimentally infected rats were also compatible with T. lewisi. However, infection with T. lewisi is rare among monkeys. We have examined more than 200 free-ranging and 160 captive monkeys and found only three infected individuals among the monkeys held in captivity. the findings of this work suggest that proximity of monkeys and infected rats and their exposure to infected fleas may be responsible for the host switching of T. Iewisi from their natural rodent species to primates. This and previous studies reporting T. lewisi in humans suggest that this trypanosome can cause sporadic and opportunistic fleaborne infection in primates. (C) 2010 Elsevier B.V. All rights reserved.
- ItemAcesso aberto (Open Access)A quick and low-cost PCR-based assay for Candida spp. identification in positive blood culture bottles(Biomed Central Ltd, 2013-10-07) Xafranski, Hemilio [UNIFESP]; Melo, Analy Salles de Azevedo [UNIFESP]; Machado, Antonia M. [UNIFESP]; Briones, Marcelo Ribeiro da Silva [UNIFESP]; Colombo, Arnaldo Lopes [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Background: Differences in the susceptibility of Candida species to antifungal drugs make identification to the species level important for clinical management of candidemia. Molecular tests are not yet standardized or available in most clinical laboratories, although such tests can reduce the time required for species identification, as compared to the conventional culture-based methods. To decrease laboratory costs and improve diagnostic accuracy, different molecular methods have been proposed, including DNA extraction protocols to produce pure DNA free of PCR inhibitors. the objective of this study was to validate a new format of molecular method, based on the internal transcribed spacer (ITS) of the rDNA gene amplification followed by sequencing, to identify common and cryptic Candida species causing candidemia by analyzing DNA in blood culture bottles positive for yeasts.Methods: for DNA extraction, an in-house protocol based on organic solvent extraction was tested. Additional steps of liquid nitrogen incubation followed by mechanical disruption ensured complete cell lysis, and highly pure DNA. One hundred sixty blood culture bottles positive for yeasts were processed. PCR assays amplified the ITS region. the DNA fragments of 152 samples were sequenced and these sequences were identified using the GenBank database (NCBI). Molecular yeast identification was compared to results attained by conventional method.Results: the organic solvent extraction protocol showed high reproducibility in regards to DNA quantity, as well as high PCR sensitivity (10 pg of C. albicans DNA and 95% amplification on PCR). the identification of species at the molecular level showed 97% concordance with the conventional culturing method. the molecular method tested in the present study also allowed identification of species not commonly implicated in human infections.Conclusions: This study demonstrated that our molecular method presents significant advantages over the conventional yeast culture identification method by providing accurate results within 24 hours, in contrast to at least 72 hours required by the automated conventional culture method. Additionally, our molecular method allowed the identification of mixed infections, as well as infections due to emergent fungal pathogens. This economical DNA extraction method developed in our laboratory provided high-quality DNA and 60% cost savings compared to commercial methods.
- ItemSomente MetadadadosRYP1 gene as a target for molecular diagnosis of histoplasmosis(Elsevier Science Bv, 2016) Nogueira Brilhante, Raimunda Samia; de Melo Guedes, Glaucia Morgana; Riello, Giovanna Barbosa; Ribeiro, Joyce Fonteles; Alencar, Lucas Pereira; Bandeira, Silviane Praciano; Collares Maia Castelo-Branco, Debora Souza; Oliveira, Jonathas Sales; Maia Freire, Janaina Maria; Lima de Mesquita, Jaco Ricarte; Camargo, Zoilo Pires de [UNIFESP]; Cordeiro, Rossana de Aguiar; Gadelha Rocha, Marcos Fabio; Costa Sidrim, Jose JulioThis study analyzed the RYP1 gene as a target for the molecular diagnosis of histoplasmosis. This assay detected fungal DNA in 13/13 blood samples from HIV/AIDS-patients with histoplasmosis. Therefore, the detection of RYP1 gene in whole blood sample is a quick and sensitive test to diagnose histoplasmosis. (C) 2016 Elsevier B.V. All rights reserved.
- ItemAcesso aberto (Open Access)Testes moleculares in-house para detecção de bactérias e genes de resistência aos antimicrobianos direto de frascos de hemoculturas(Universidade Federal de São Paulo (UNIFESP), 2017-03-14) Quiles, Milene Goncalves [UNIFESP]; Pignatari, Antonio Carlos Campos [UNIFESP]; http://lattes.cnpq.br/9461346610553865; http://lattes.cnpq.br/3344199283268794; Universidade Federal de São Paulo (UNIFESP)ABSTRACT Bloodstream infections (BSI) are important causes of morbidity and mortality. Recent studies described rates higher than 500,000 BSI episodes per year with more than 79,000 deaths annually. Molecular methods become increasingly frequent in clinical laboratories. The implantation of these methods in laboratory routine allows great sensitivity and speed in the results, collaborating for the therapeutic conduct of these infections. In order to validate the combined use of MALDI-TOF MS and in-house real-time PCR techniques for the rapid diagnosis of BSIs, we developed three studies: Study 1: This is a overview of commercial molecular tests and platforms available for the diagnosis of BSI, as well the clinical impact described when using these new technologies. Study 2: The purpose of this study was to validate a molecular protocol to identify bacteria and resistance genes in 166 positive blood cultures from 139 patients admitted to three different hospitals and to compare the results with those obtained from routine phenotypic methods. There was overall agreement for genius identification in 95.4% and at species level in 81.8% of the samples. In Enterobacteriaceae, the detection of carbapenem-resistance was concordant in 95.5% and cephalosporins (ESBL profile) in 87.5%. Among non-fermentative rods, there was agreement in 80% in the detection of carbapenem-resistance. For Gram positive, the methods agreed on 100% for the detection of vancomycin-resistance in enterococci and 77.1% for methicillin-resistance in staphylococci. Study 3: This study aimed to determine the intra-laboratory time required to identify pathogens and resistance genes in 113 episodes of ICS which molecular results were conclusive, as well as the evaluation of the antimicrobial adequacy in these episodes after the immediate communication of the results to phisycians from three participating centers. The mean untecipation time for results was 35 hours from traditional blood culture. Antimicrobial therapeutic modification occurred in 25 episodes, in which 16 were escalate and 10 de-escalate agents. In these cases, the antibiotics were adequate in 22 and inadequate in 3 which molecular results were discordants of the phenotypic. The major modifications occurred in Gram negative microorganisms, with the prescription of carbapenems in six episodes and polymyxin B in three. Conclusion: The molecular protocol proved to be in good agreement with conventional routine tests. In addition, the protocol provided a rapid result, considerably anticipating the time to antimicrobial therapeutic adequacy of the BSIs episodes.