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Activation of myeloid dendritic cells, effector cells and regulatory T cells in lichen planus
No full textAbstract\ud
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Background\ud
Lichen planus (LP) is a chronic mucocutaneous inflammatory disease. Evaluating the balance between regulatory T cells and effector T cells could be useful for monitoring the proinflammatory profile of LP. Therefore, this study aimed to assess populations of dendritic cells (DCs) and regulatory and effector T cells in peripheral blood samples collected from patients with LP to evaluate the polyfunctionality of T cells upon toll-like receptor (TLR) activation.\ud
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Methods\ud
Peripheral blood mononuclear cells collected from 18 patients with LP and 22 healthy control subjects were stimulated with agonists of TLR4, TLR7, TLR7/TLR8 or TLR9. Frequencies of circulating IFN-α+ plasmacytoid DCs (pDCs); TNF-α+ myeloid DCs (mDCs); regulatory T cells (Tregs); and IL-17-, IL-10-, IL-22-, TNF-, and IFN-γ-secreting T cells were assessed via flow cytometry.\ud
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Results\ud
The frequencies of regulatory CD4+ and CD8+CD25+Foxp3+CD127low/− T cells and TNF-α+ mDCs were induced following activation with TLR4, TLR7 and TLR8 agonists in the LP group. Moreover, increased baseline frequencies of CD4+IL-10+ T cells and CD8+IL-22+ or IFN-γ+T cells were found. In the LP group, TLR4 activation induced an increased frequency of CD4+IFN-γ+ T cells, while TLR7/8 and staphylococcal enterotoxin B (SEB) activation induced an increased frequency of CD8+ IL-22+ T cells. An increased frequency of polyfunctional CD4+ T cells that simultaneously secreted 3 of the evaluated cytokines (not including IL-10) was verified upon TLR7/8/9 activation, while polyfunctional CD8+ T cells were already detectable at baseline.\ud
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Conclusions\ud
TLR-mediated activation of the innate immune response induced the production of proinflammatory mDCs, Tregs and polyfunctional T cells in patients with LP. Therefore, TLR activation has an adjuvant role in inducing both innate and adaptive immune responses.This work was supported by Fundação de Amparo a Pesquisa do Estado de\ud
São Paulo (2011/20740-3) and the Laboratory of Dermatology and Immunodeficiencies,\ud
LIM-56, Department of Dermatology, Medical School, University\ud
of São Paulo, Brazil
Simplificação da descrição termodinâmica do sistema Ti-Si
No full textThe thermodynamic optimization of ternary or higher order systems containing Ti requires that the Ti-X binary\ud
systems are continuously updated. The Ti-Si system has been studied and thermodynamically optimized since de 1950s.\ud
The Ti5Si3 phase was initially considered stoichiometric to facilitate the thermodynamic calculations, although experimental\ud
results showed that this phase was a non-stoichiometric intermetallic. The most recent optimization of the Ti-Si system\ud
described this phase as a non-stoichiometric intermetallic with three sublattices, using the sub-lattice model. The problem of\ud
this approach is that it increases considerably the number of variables to be optimized during the calculation of the Ti-Si-X\ud
phase diagrams, hindering the convergence of the computational processing. The present work simplifies the optimization\ud
of the Ti-Si system, assuming that Ti5Si3 phase is mostly hyper-stoichiometric in relation to Ti. The results showed that this\ud
simplification did not significantly affect the phase diagram and the thermodynamic properties calculated for the system
Use of Electrochemical Tests for Assessment of the Effect of Erosive Particle Size on the Erosion-Corrosion Behaviour of AISI 304L Austenitic Stainless Steel.
No full textThe degradation of AISI 304L stainless steel under static corrosion, liquid impingement and corrosion-erosion was studied using polarization curves. Static corrosion and liquid impingement tests were performed in 3.5% NaCl solution. Corrosion-erosion tests were performed in the same solution, containing 10 wt-% of three different SiO2 particle sizes. Synergism between erosion and corrosion was correlated to shifts in the polarization curves. The passive current densities increased and the pitting potential decreased for liquid impingement and with addition of SiO2 particles to the electrolyte. Increasing the particle size led to a greater increase in the current densities, although the pitting potential did not significantly changed. The effects of erosion on corrosion are discussed in terms of the passive film breakdown and reformation.CNPQFAPES
Virus-like attachment sites as structural landmarks of plants retrotransposons
No full textAbstract\ud
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Background\ud
The genomic data available nowadays has enabled the study of repetitive sequences and their relationship to viruses. Among them, long terminal repeat retrotransposons (LTR-RTs) are the largest component of most plant genomes, the Gypsy and Copia superfamilies being the most common. Recently it has been found that Del lineage, an LTR-RT of Gypsy superfamily, has putative virus-like attachment (vl-att) sites. This signature, originally described for retroviruses, is recognized by retroviral integrase conferring specificity to the integration process.\ud
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Results\ud
Here we retrieved 26,092 putative complete LTR-RTs from 10 lineages found in 10 fully sequenced angiosperm genomes and found putative vl-att sites that are a conserved structural landmark across these genomes. Furthermore, we reveal that each plant genome has a distinguishable LTR-RT lineage amplification pattern that could be related to the vl-att sites diversity. We used these patterns to generate a specific quick-response (QR) code for each genome that could be used as a barcode of identification of plants in the future.\ud
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Conclusions\ud
The universal distribution of vl-att sites represents a new structural feature common to plant LTR-RTs and retroviruses. This is an important finding that expands the information about the structural similarity between LTR-RT and retroviruses. We speculate that the sequence diversity of vl-att sites could be important for the life cycle of retrotransposons, as it was shown for retroviruses. All the structural vl-att site signatures are strong candidates for further functional studies. Moreover, this is the first identification of specific LTR-RT content and their amplification patterns in a large dataset of LTR-RT lineages and angiosperm genomes. These distribution patterns could be used in the future with biotechnological identification purposes.This manuscript was reviewed by a professional science editor and by a\ud
native English-speaking copy editor to improve readability.\ud
We gratefully acknowledge funding from FAPESP-BIOEN (08/52074-0) and\ud
CNPq (308197/2010-0) to MAVS. EAOC (12/21064-4), GMQC (08/58243-8) and\ud
AVP (12/02671-7) are supported by FAPESP fellowships. EAOC; GMQC and\ud
AVP designed and performed the experiments. EAOC and MAVS analyzed\ud
the data and wrote the manuscript
Acinetobacter spp. are associated with a higher mortality in intensive care patients with bacteremia: a survival analysis
No full textAbstract\ud
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Background\ud
It has been challenging to determine the true clinical impact of Acinetobacter spp., due to the predilection of this pathogen to colonize and infect critically ill patients, who often have a poor prognosis. The aim of this study was to assess whether Acinetobacter spp. bacteremia is associated with lower survival compared with bacteremia caused by other pathogens in critically ill patients.\ud
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Methods\ud
This study was performed at Hospital das Clínicas, University of São Paulo, Brazil. There are 12 intensive care units (ICUs) in the hospital: five Internal Medicine ICUs (emergency, nephrology, infectious diseases and respiratory critical care), three surgical ICU (for general surgery and liver transplantion), an Emergency Department ICU for trauma patients, an ICU for burned patients, a neurosurgical ICU and a post-operative ICU. A retrospective review of medical records was conducted for all patients admitted to any of the ICUs, who developed bacteremia from January 2010 through December 2011. Patients with Acinetobacter spp. were compared with those with other pathogens (Klebsiella pneumoniae, Staphylococcus aureus, Enterobacter spp., Enterococcus spp., Pseudomonas aeruginosa). We did a 30-day survival analysis. The Kaplan-Meier method and log-rank test were used to determine the overall survival. Potential prognostic factors were identified by bivariate and multivariate Cox regression analysis.\ud
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Results\ud
One hundred forty-one patients were evaluated. No differences between patients with Acinetobacter spp. and other pathogens were observed with regard to age, sex, APACHE II score, Charlson Comorbidity Score and type of infection. Initial inappropriate antimicrobial treatment was more frequent in Acinetobacter bacteremia (88 % vs 51 %). Bivariate analysis showed that age > 60 years, diabetes mellitus, and Acinetobacter spp. infection were significantly associated with a poor prognosis. Multivariate model showed that Acinetobacter spp. infection (HR = 1.93, 95 % CI: 1.25–2.97) and age > 60 years were independent prognostic factors.\ud
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Conclusion\ud
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Acinetobacter is associated with lower survival compared with other pathogens in critically ill patients with bacteremia, and is not merely a marker of disease severity
Apocynin influence on oxidative stress and cardiac remodeling of spontaneously hypertensive rats with diabetes mellitus
No full textAbstract
Purpose
Although increased oxidative stress is a major component of diabetic hypertensive cardiomyopathy, research into the effects of antioxidants on cardiac remodeling remains scarce. The actions of antioxidant apocynin include inhibiting reactive oxygen species (ROS) generation by nicotinamide adenine dinucleotide phosphate (NADPH) oxidases and ROS scavenging. We evaluated the effects of apocynin on cardiac remodeling in spontaneously hypertensive rats (SHR) with diabetes mellitus (DM).
Methods
Male SHR were divided into four groups: control (SHR, n = 16); SHR treated with apocynin (SHR-APO; 16 mg/kg/day, added to drinking water; n = 16); diabetic SHR (SHR-DM, n = 13); and SHR-DM treated with apocynin (SHR-DM-APO, n = 14), for eight weeks. DM was induced by streptozotocin (40 mg/kg, single dose). Statistical analyzes: ANOVA and Tukey or Mann–Whitney.
Results
Echocardiogram in diabetic groups showed higher left ventricular and left atrium diameters indexed for body weight, and higher isovolumetric relaxation time than normoglycemic rats; systolic function did not differ between groups. Isolated papillary muscle showed impaired contractile and relaxation function in diabetic groups. Developed tension was lower in SHR-APO than SHR. Myocardial hydroxyproline concentration was higher in SHR-DM than SHR, interstitial collagen fraction was higher in SHR-DM-APO than SHR-APO, and type III collagen protein expression was lower in SHR-DM and SHR-DM-APO than their controls. Type I collagen and lysyl oxidase expression did not differ between groups. Apocynin did not change collagen tissue. Myocardial lipid hydroperoxide concentration was higher in SHR-DM than SHR and SHR-DM-APO. Glutathione peroxidase activity was lower and catalase higher in SHR-DM than SHR. Apocynin attenuated antioxidant enzyme activity changes in SHR-DM-APO. Advanced glycation end-products and NADPH oxidase activity did not differ between groups.
Conclusion
Apocynin reduces oxidative stress independently of NADPH oxidase activity and does not change ventricular or myocardial function in spontaneously hypertensive rats with diabetes mellitus. The apocynin-induced myocardial functional impairment in SHR shows that apocynin actions need to be clarified during sustained chronic pressure overload
The relationship of the oleic acid level and ECHDC3 mRNA expression with the extent of coronary lesion
No full textAbstract\ud
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Background\ud
The fatty acid profile is associated with the risk and progression of several diseases, probably via mechanisms including its influence on gene expression. We previously reported a correlation between ECHDC3 upregulation and the severity of acute coronary syndrome. Here, we assessed the relationship of serum fatty acid profile and ECHDC3 expression with the extent of coronary lesion.\ud
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Methods\ud
Fifty-nine individuals aged 30 to 74 years and undergoing elective cinecoronariography for the first time were enrolled in the present study. The extent of coronary lesion was assessed by the Friesinger index and patients were classified as without lesion (n = 18), low lesion (n = 17), intermediate lesion (n = 17) and major lesion (n = 7). Serum biochemistry, fatty acid concentration, and ECHDC3 mRNA expression in blood were evaluated.\ud
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Results\ud
Elevated serum levels of oleic acid and total monounsaturated fatty acids were observed in patients with low and intermediate lesion, when compared to patients without lesion (p < 0.05). ECHDC3 mRNA expression was 1.2 fold higher in patients with low lesion than in patients without lesion (p = 0.020), and 1.8 fold lower in patients with major lesion patients than in patients with low lesion (p = 0.023).\ud
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Conclusion\ud
Increased levels of monounsaturated fatty acids, especially oleic acid, and ECHDC3 upregulation in patients with coronary artery lesion suggests that these are independent factors associated with the initial progression of cardiovascular disease.A.A.F. Carioca is recipient of fellowships from FAPESP, Brazil. V.H.R. Duarte\ud
and R.H. Bortolin are recipients of fellowships from CAPES, Brazil
SiMPle: assessing music similarity using subsequences joins
No full textMost algorithms for music information retrieval are based on the analysis of the similarity between feature sets extracted from the raw audio. A common approach to assessing similarities within or between recordings is by creating similarity matrices. However, this approach requires quadratic space for each comparison and typically requires a costly post-processing of the matrix. In this work, we propose a simple and efficient representation based on a subsequence similarity join, which may be used in several music information retrieval tasks. We apply our method to the cover song recognition problem and demonstrate that it is superior to state-of-the-art algorithms. In addition, we demonstrate how the proposed representation can be exploited for multiple applications in music processing.FAPESP (grants #2013/26151-5 and #2015/07628-0)CNPq (grants #303083/2013-1 and #446330/2014-0)NSF (grant IIS 1510741