171 research outputs found
Thermodynamic behavior of short oligonucleotides in microarray hybridizations can be described using Gibbs free energy in a nearest-neighbor model
While designing oligonucleotide-based microarrays, cross-hybridization
between surface-bound oligos and non-intended labeled targets is probably the
most difficult parameter to predict. Although literature describes
rules-of-thumb concerning oligo length, overall similarity, and continuous
stretches, the final behavior is difficult to predict. The aim of this study
was to investigate the effect of well-defined mismatches on hybridization
specificity using CodeLink Activated Slides, and to study quantitatively the
relation between hybridization intensity and Gibbs free energy (Delta G),
taking the mismatches into account. Our data clearly showed a correlation
between the hybridization intensity and Delta G of the oligos over three orders
of magnitude for the hybridization intensity, which could be described by the
Langmuir model. As Delta G was calculated according to the nearest-neighbor
model, using values related to DNA hybridizations in solution, this study
clearly shows that target-probe hybridizations on microarrays with a
three-dimensional coating are in quantitative agreement with the corresponding
reaction in solution. These results can be interesting for some practical
applications. The correlation between intensity and Delta G can be used in
quality control of microarray hybridizations by designing probes and
corresponding RNA spikes with a range of Delta G values. Furthermore, this
correlation might be of use to fine-tune oligonucleotide design algorithms in a
way to improve the prediction of the influence of mismatching targets on
microarray hybridizations.Comment: 32 pages on a single pdf fil
Epithelium and stroma from nasal polyp mucosa exhibits inverse expression of TGF- beta(1) as compared with healthy nasal mucosa
Objective: To evaluate TGF-beta(1) expression in polypoid mucosa (epithelium and stroma) of patients with chronic rhinosinusitis with nasal polyposis (CRSwNP).Methods: Cross-sectional study with two groups: 17 patients with nasal polyposis and 11 controls. Polyps and normal nasal mucosa were processed by immunohistochemical methods for TGF-beta 1 visualization. Then, the percentage of TGF-beta 1 expression in stroma and epithelium was objectively quantified using UT Morph software.Results: A lower percentage of positive expression was found in the epithelium of CRSwNP patients (32.44%) versus normal controls (55.91%) (p < 0.05), and a higher percentage of positive expression in the stroma of CRSwNP patients (23.24%) versus controls (5.88%) (p < 0.05).Conclusion: the lower percentage of TGF-beta(1) expression in the nasal epithelium of CRSwNP patients may have an impact on epithelium-directed topical treatments employed in this patient population.Universidade Federal de São Paulo, Dept Otolaryngol Head & Neck Surg, São Paulo, BrazilUniv Ghent, Ghent Univ Hosp, Dept Otorhinolaryngol, Upper Airway Res Lab, B-9000 Ghent, BelgiumUniversidade Federal de São Paulo, Dept Pathol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Otolaryngol Head & Neck Surg, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pathol, São Paulo, BrazilWeb of Scienc
Comparative Study of the Standard Fluorescent Antibody to Membrane Antigen (FAMA) Assay and a Flow Cytometry-Adapted FAMA Assay To Assess Immunity to Varicella-Zoster Virus
A flow cytometry-adapted fluorescent antibody to membrane antigen (FAMA) assay to detect IgG antibodies against varicella-zoster virus (VZV) was developed and tested in 62 serum samples, showing 90.32% accuracy obtained from a receiver operating characteristic (ROC) curve with a 0.9125 (95% confidence interval [CI], 0.829 to 1.00) area below the curve compared to the result with standard FAMA.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fed Univ São Paulo UNIFESP EPM, Div Pediat Infect Dis, BR-04040000 São Paulo, BrazilColumbia Univ, Dept Pediat, Coll Phys & Surg, New York, NY 10027 USAFed Univ São Paulo UNIFESP EPM, Div Pediat Infect Dis, BR-04040000 São Paulo, BrazilCAPES: 0108-08-1Web of Scienc
Mycobacterium leprae is identified in the oral mucosa from paucibacillary and multibacillary leprosy patients
In leprosy, the nasal mucosa is considered as the principal route of transmission for the bacillus Mycobacterium leprae. the objective of this study was to identify M.leprae in the oral mucosa of 50 untreated leprosy patients, including 21 paucibacillary (PB) and 29 multibacillary (MB) patients, using immunohistochemistry (IHC), with antibodies against bacillus Calmette-Guerin (BCG) and phenolic glycolipid antigen-1 (PGL-1), and polymerase chain reaction (PCR), with MntH-specific primers for M.leprae, and to compare the results. the material was represented by 163 paraffin blocks containing biopsy samples obtained from clinically normal sites (including the tongue, buccal mucosa and soft palate) and visible lesions anywhere in the oral mucosa. All patients and 158 available samples were included for IHC study. Among the 161 available samples for PCR, 110 had viable DNA. There was viable DNA in at least one area of the oral mucosa for 47 patients. M.leprae was detected in 70% and 78% of patients using IHC and PCR, respectively, and in 94% of the patients by at least one of the two diagnostic methods. There were no differences in detection of M.leprae between MB and PB patients. Similar results were obtained using anti-BCG and anti-PGL-1 antibodies, and immunoreactivity occurred predominantly on free-living bacteria on the epithelial surface, with a predilection for the tongue. Conversely, there was no area of predilection according to the PCR results. M.leprae is present in the oral mucosa at a high frequency, implicating this site as a potential means of leprosy transmission.Univ Oeste Paulista, Presidente Prudente Reg Hosp, Dermatol Unit, Presidente Prudente, BrazilUniversidade Federal de São Paulo, Dept Dermatol, São Paulo, BrazilUniv São Paulo, Multiuser Mol Biol Lab, Div Dermatol, Dept Clin Med,Ribeirao Preto Coll Med, BR-14049 Ribeirao Preto, BrazilAdolfo Lutz Inst, Dept Pathol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Dermatol, São Paulo, BrazilWeb of Scienc
Nonequilibrium effects in DNA microarrays: a multiplatform study
It has recently been shown that in some DNA microarrays the time needed to
reach thermal equilibrium may largely exceed the typical experimental time,
which is about 15h in standard protocols (Hooyberghs et al. Phys. Rev. E 81,
012901 (2010)). In this paper we discuss how this breakdown of thermodynamic
equilibrium could be detected in microarray experiments without resorting to
real time hybridization data, which are difficult to implement in standard
experimental conditions. The method is based on the analysis of the
distribution of fluorescence intensities I from different spots for probes
carrying base mismatches. In thermal equilibrium and at sufficiently low
concentrations, log I is expected to be linearly related to the hybridization
free energy with a slope equal to , where is
the experimental temperature and R is the gas constant. The breakdown of
equilibrium results in the deviation from this law. A model for hybridization
kinetics explaining the observed experimental behavior is discussed, the
so-called 3-state model. It predicts that deviations from equilibrium yield a
proportionality of to . Here, is an
effective temperature, higher than the experimental one. This behavior is
indeed observed in some experiments on Agilent arrays. We analyze experimental
data from two other microarray platforms and discuss, on the basis of the
results, the attainment of equilibrium in these cases. Interestingly, the same
3-state model predicts a (dynamical) saturation of the signal at values below
the expected one at equilibrium.Comment: 27 pages, 9 figures, 1 tabl
Non-linear Autoregressive Neural Networks to Forecast Short-Term Solar Radiation for Photovoltaic Energy Predictions
Nowadays, green energy is considered as a viable solution to hinder CO2 emissions and greenhouse effects. Indeed, it is expected that Renewable Energy Sources (RES) will cover 40% of the total energy request by 2040. This will move forward decentralized and cooperative power distribution systems also called smart grids. Among RES, solar energy will play a crucial role. However, reliable models and tools are needed to forecast and estimate with a good accuracy the renewable energy production in short-term time periods. These tools will unlock new services for smart grid management.
In this paper, we propose an innovative methodology for implementing two different non-linear autoregressive neural networks to forecast Global Horizontal Solar Irradiance (GHI) in short-term time periods (i.e. from future 15 to 120min). Both neural networks have been implemented, trained and validated exploiting a dataset consisting of four years of solar radiation values collected by a real weather station. We also present the experimental results discussing and comparing the accuracy of both neural networks. Then, the resulting GHI forecast is given as input to a Photovoltaic simulator to predict energy production in short-term time periods. Finally, we present the results of this Photovoltaic energy estimation discussing also their accuracy
Relative Efficacy of AS03-Adjuvanted Pandemic Influenza A(H1N1) Vaccine in Children: Results of a Controlled, Randomized Efficacy Trial
Background. the vaccine efficacy (VE) of 1 or 2 doses of AS03-adjuvanted influenza A(H1N1) vaccine relative to that of 2 doses of nonadjuvanted influenza A(H1N1) vaccine in children 6 months to <10 years of age in a multinational study conducted during 2010-2011.Methods. A total of 6145 children were randomly assigned at a ratio of 1: 1: 1 to receive 2 injections 21 days apart of A/California/7/2009(H1N1)-AS03 vaccine at dose 1 and saline placebo at dose 2, 2 doses 21 days apart of A/California/7/2009(H1N1)-AS03 vaccine (the Ad2 group), or 2 doses 21 days apart of nonadjuvanted A/California/7/2009(H1N1) vaccine (the NAd2 group). Active surveillance for influenza-like illnesses continued from days 14 to 385. Nose and throat samples obtained during influenza-like illnesses were tested for A/California/7/2009 (H1N1), using reverse-transcriptase polymerase chain reaction. Immunogenicity, reactogenicity, and safety were assessed.Results. There were 23 cases of confirmed 2009 pandemic influenza A(H1N1) (A[H1N1]pdm09) infection for the primary relative VE analysis. the VE in the Ad2 group relative to that in the NAd2 group was 76.8% (95% confidence interval, 18.5%-93.4%). the benefit of the AS03 adjuvant was demonstrated in terms of the greater immunogenicity observed in the Ad2 group, compared with the NAd2 group.Conclusion. the 4-8-fold antigen-sparing adjuvanted pandemic influenza vaccine demonstrated superior and clinically important prevention of A(H1N1)pdm09 infection, compared with nonadjuvanted vaccine, with no observed increase in medically attended or serious adverse events. These data support the use of adjuvanted influenza vaccines during influenza pandemics.GlaxoSmithKline BiologicalsUniv Melbourne, Murdoch Childrens Res Inst, Carlton, Vic 3010, AustraliaUniv Melbourne, Melbourne Sch Populat & Global Hlth, Carlton, Vic 3010, AustraliaGlaxoSmithKline Vaccines, King of Prussia, PA USANovavax, Rockville, MD USAMary Chiles Gen Hosp, Dept Pediat, Manila, PhilippinesDe La Salle Hlth Sci Inst, Dept Pediat, Dasmarinas City, PhilippinesRes Inst Trop Med, Dept Hlth, Muntinlupa, PhilippinesUniversidade Federal de São Paulo, Dept Pediat, São Paulo, BrazilFac Ciencias Med Santa Casa São Paulo, Dept Pediat, São Paulo, BrazilAssoc Fundo Incent Pesquisa, São Paulo, BrazilInst Costarricense Invest Clin, San Jose, Costa RicaNatl Inst Publ Hlth Mexico, Cuernavaca, Morelos, MexicoUniv Autonoma Nuevo Leon, Serv Med, Monterrey, MexicoInst Nacl Pediat Mexico, Mexico City, DF, MexicoHosp Gen Durango, Durango, MexicoPhramongkutklao Hosp, Infect Dis Unit, Dept Pediat, Bangkok, ThailandKhon Kaen Univ, Dept Pediat, Fac Med, Khon Kaen, ThailandNatl Healthcare Grp Polyclin, Singapore, SingaporeCtr Estudios Infect Pediat, Cali, ColombiaGlaxoSmithKline Vaccines, Wavre, BelgiumGlaxoSmithKline Vaccines, Rixensart, BelgiumUniversidade Federal de São Paulo, Dept Pediat, São Paulo, BrazilWeb of Scienc
Prevalence of IgG varicella zoster virus antibodies in the Kuikuro and Kaiabi indigenous communities in Xingu National Park, Brazil, before varicella vaccination
Paroxysmal exercise-induced dyskinesia and epilepsy is due to mutations in SLC2A1, encoding the glucose transporter GLUT1
Paroxysmal exercise-induced dyskinesia (PED) can occur in isolation or in association with epilepsy, but the genetic causes and pathophysiological mechanisms are still poorly understood. We performed a clinical evaluation and genetic analysis in a five-generation family with co-occurrence of PED and epilepsy (n = 39), suggesting that this combination represents a clinical entity. Based on a whole genome linkage analysis we screened SLC2A1, encoding the glucose transporter of the blood-brain-barrier, GLUT1 and identified heterozygous missense and frameshift mutations segregating in this and three other nuclear families with a similar phenotype. PED was characterized by choreoathetosis, dystonia or both, affecting mainly the legs. Predominant epileptic seizure types were primary generalized. A median CSF/blood glucose ratio of 0.52 (normal >0.60) in the patients and a reduced glucose uptake by mutated transporters compared with the wild-type as determined in Xenopus oocytes confirmed a pathogenic role of these mutations. Functional imaging studies implicated alterations in glucose metabolism in the corticostriate pathways in the pathophysiology of PED and in the frontal lobe cortex in the pathophysiology of epileptic seizures. Three patients were successfully treated with a ketogenic diet. In conclusion, co-occurring PED and epilepsy can be due to autosomal dominant heterozygous SLC2A1 mutations, expanding the phenotypic spectrum associated with GLUT1 deficiency and providing a potential new treatment option for this clinical syndrome
Phylogenetic Analysis of a Spontaneous Cocoa Bean Fermentation Metagenome Reveals New Insights into Its Bacterial and Fungal Community Diversity
This is the first report on the phylogenetic analysis of the community diversity of a single spontaneous cocoa bean box fermentation sample through a metagenomic approach involving 454 pyrosequencing. Several sequence-based and composition-based taxonomic profiling tools were used and evaluated to avoid software-dependent results and their outcome was validated by comparison with previously obtained culture-dependent and culture-independent data. Overall, this approach revealed a wider bacterial (mainly γ-Proteobacteria) and fungal diversity than previously found. Further, the use of a combination of different classification methods, in a software-independent way, helped to understand the actual composition of the microbial ecosystem under study. In addition, bacteriophage-related sequences were found. The bacterial diversity depended partially on the methods used, as composition-based methods predicted a wider diversity than sequence-based methods, and as classification methods based solely on phylogenetic marker genes predicted a more restricted diversity compared with methods that took all reads into account. The metagenomic sequencing analysis identified Hanseniaspora uvarum, Hanseniaspora opuntiae, Saccharomyces cerevisiae, Lactobacillus fermentum, and Acetobacter pasteurianus as the prevailing species. Also, the presence of occasional members of the cocoa bean fermentation process was revealed (such as Erwinia tasmaniensis, Lactobacillus brevis, Lactobacillus casei, Lactobacillus rhamnosus, Lactococcus lactis, Leuconostoc mesenteroides, and Oenococcus oeni). Furthermore, the sequence reads associated with viral communities were of a restricted diversity, dominated by Myoviridae and Siphoviridae, and reflecting Lactobacillus as the dominant host. To conclude, an accurate overview of all members of a cocoa bean fermentation process sample was revealed, indicating the superiority of metagenomic sequencing over previously used techniques
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