Single Cell Multi-Omics of an iPSC Model of Human Sinoatrial Node Development Reveals Genetic Determinants of Heart Rate and Arrhythmia Susceptibility.

Cellular heterogeneity within the sinoatrial node (SAN) is functionally important but has been difficult to model in vitro , presenting a major obstacle to studies of heart rate regulation and arrhythmias. Here we describe a scalable method to derive sinoatrial node pacemaker cardiomyocytes (PCs) from human induced pluripotent stem cells that recapitulates differentiation into distinct PC subtypes, including SAN Head, SAN Tail, transitional zone cells, and sinus venosus myocardium. Single cell (sc) RNA-sequencing, sc-ATAC-sequencing, and trajectory analyses were used to define epigenetic and transcriptomic signatures of each cell type, and to identify novel transcriptional pathways important for PC subtype differentiation. Integration of our multi-omics datasets with genome wide association studies uncovered cell type-specific regulatory elements that associated with heart rate regulation and susceptibility to atrial fibrillation. Taken together, these datasets validate a novel, robust, and realistic in vitro platform that will enable deeper mechanistic exploration of human cardiac automaticity and arrhythmia.

Phagocytosis increases an oxidative metabolic and immune suppressive signature in tumor macrophages.

Phagocytosis is a key macrophage function, but how phagocytosis shapes tumor-associated macrophage (TAM) phenotypes and heterogeneity in solid tumors remains unclear. Here, we utilized both syngeneic and novel autochthonous lung tumor models in which neoplastic cells express the fluorophore tdTomato (tdTom) to identify TAMs that have phagocytosed neoplastic cells in vivo. Phagocytic tdTompos TAMs upregulated antigen presentation and anti-inflammatory proteins, but downregulated classic proinflammatory effectors compared to tdTomneg TAMs. Single-cell transcriptomic profiling identified TAM subset-specific and common gene expression changes associated with phagocytosis. We uncover a phagocytic signature that is predominated by oxidative phosphorylation (OXPHOS), ribosomal, and metabolic genes, and this signature correlates with worse clinical outcome in human lung cancer. Expression of OXPHOS proteins, mitochondrial content, and functional utilization of OXPHOS were increased in tdTompos TAMs. tdTompos tumor dendritic cells also display similar metabolic changes. Our identification of phagocytic TAMs as a distinct myeloid cell state links phagocytosis of neoplastic cells in vivo with OXPHOS and tumor-promoting phenotypes.

Antiadherent AgBDC Metal-Organic Framework Coating for Escherichia coli Biofilm Inhibition.

Surface microbial colonization and its potential biofilm formation are currently a major unsolved problem, causing almost 75% of human infectious diseases. Pathogenic biofilms are capable of surviving high antibiotic doses, resulting in inefficient treatments and, subsequently, raised infection prevalence rates. Antibacterial coatings have become a promising strategy against the biofilm formation in biomedical devices due to their biocidal activity without compromising the bulk material. Here, we propose for the first time a silver-based metal-organic framework (MOF; here denoted AgBDC) showing original antifouling properties able to suppress not only the initial bacterial adhesion, but also the potential surface contamination. Firstly, the AgBDC stability (colloidal, structural and chemical) was confirmed under bacteria culture conditions by using agar diffusion and colony counting assays, evidencing its biocide effect against the challenging E. coli, one of the main representative indicators of Gram-negative resistance bacteria. Then, this material was shaped as homogeneous spin-coated AgBDC thin film, investigating its antifouling and biocide features using a combination of complementary procedures such as colony counting, optical density or confocal scanning microscopy, which allowed to visualize for the first time the biofilm impact generated by MOFs via a specific fluorochrome, calcofluor.

Incidence, Mortality and Survival of Pediatric Cancer in Uruguay 2011-2015

Introduction: Childhood cancer is a small proportion of all cancers but is still a major public health problem. Objective: To describe the 5-year incidence and mortality rates and net survival of childhood cancer in Uruguay. Method: Data on all malignant tumors diagnosed in children aged 0-14 were included for the period 2011-2015, obtained from the National Pediatric Registry of Cancer and from the Ministry of Health Mortality Registry, classified according to the International Classification of Childhood Cancer (ICCC-3). Information on the total population was obtained from national census records. Follow up was made until December 2020. Results: The standardized incidence rate was 128/million children per year. The distribution of the disease was similar to developed countries. The overall mortality rate was 28.2/million, with a net overall survival of 79.6% for the total population. Conclusion: Childhood cancer incidence in Uruguay is similar to developed countries. Progress in diagnosis and care have improved survival immensely, but efforts must continue to keep this trend and ameliorate the outcomes.

Introdução: O câncer em crianças representa uma pequena proporção de todos os cânceres, mas continua a ser um importante problema de saúde pública. Objetivo: Descrever a incidência e a mortalidade, bem como a sobrevida do câncer infantil no Uruguai por um período de cinco anos. Método: Foram incluídos todos os tumores malignos diagnosticados em crianças de 0 a 14 anos de 2011 a 2015. Os dados foram obtidos do Registro Nacional de Câncer e dos Registros de Mortalidade do Ministério da Saúde. Os casos foram classificados de acordo com a International Classification of Childhood Cancer (ICCC-3). A informação total sobre a população foi obtida a partir de registros do censo nacional. O acompanhamento foi feito até dezembro de 2020. Resultados: A taxa de incidência padronizada foi de 128/milhão de crianças por ano. A distribuição foi semelhante à dos países industrializados. A taxa de mortalidade global foi de 28,2/milhão, com sobrevida global líquida de 79,6% para a população total. Conclusão: A incidência de câncer infantil no Uruguai é semelhante à dos países desenvolvidos. Os avanços no diagnóstico e no atendimento melhoraram substancialmente a sobrevida, mas os esforços devem continuar para se obter melhores resultados.

Introducción: El cáncer en los niños constituye una pequeña proporción de todos los cánceres pero continúa siendo un importante problema de salud pública. Objetivo: Describir la incidencia y mortalidad, así como la sobrevida neta del cáncer infantil en nuestro país durante cinco años. Método: Se incluyeron todos los tumores malignos diagnosticados en niños entre 0 y 14 años desde 2011 a 2015. Los datos se obtuvieron del Registro Nacional del Cáncer así como de los Registros de Mortalidad del Ministerio de Salud. Los casos se clasificaron de acuerdo con International Classification of Childhood Cancer (ICCC-3). La información de la población total fue obtenida de los registros nacionales de censo. El seguimiento se hizo hasta diciembre de 2020. Resultados: La tasa de incidencia estandarizada fue de 128/millón de niños por año. La distribución fue similar a la de los países industrializados. La tasa de mortalidad global fue de 28,2/millón, con una sobrevida global neta de 79,6% para el grupo total. Conclusión: La incidencia de cáncer infantil en Uruguay es similar a la de los países desarrollados. Los avances en el diagnóstico y el cuidado han mejorado notablemente la sobrevida, pero se deben continuar los esfuerzos para seguir mejorando los resultados.

Room-temperature synthesis of nanometric and luminescent silver-MOFs.

Three silver-MOFs were prepared using an optimized, room-temperature methodology starting from AgNO3 and dicarboxylate ligands in water/ethanol yielding Ag 2 BDC, Ag 2 NDC (UAM-1), and Ag 2 TDC (UAM-2) at 38%-48% (BDC, benzenedicarboxylate; NDC, 1,8-naphthalene-dicarboxylate; TDC, p-terphenyl-4,4″-dicarboxylate). They were characterized by PXRD/FT-IR/TGA/photoluminescence spectroscopy, and the former two by SEM. These materials started decomposing at 330°C, while showing stability. The crystal structure of UAM-1 was determined by PXRD, DFT calculations, and Rietveld refinement. In general, the structure was 3D, with the largest Ag-O bond interlinking 2D layers. The FT-IR spectra revealed 1450 and 1680 bands (cm-1) of asymmetrically stretching aniso-/iso-bidentate -COO in coordination with 2/3-Ag atoms, accompanied by Ag-O bands at 780-740 cm-1, all demonstrating the network formation. XRD and SEM showed nanometric-scale crystals in Ag2BDC, and UAM-1 developed micrometric single-stranded/agglomerated fibrillar particles of varying nanometric widths. Luminescence spectroscopy showed emission by Ag2BDC, which was attributed to ligand-to-metal or ligand-to-metal-metal transitions, suggesting energy transfer due to the short distance between adjacent BDC molecules. UAM-1 and UAM-2 did not show luminescence emission attributable to ligand-to-metal transition; rather, they presented only UV emission. The stabilities of Ag2BDC and UAM-1 were evaluated in PBS/DMEM/DMEM+FBS media by XRD, which showed that they lost their crystallinity, resulting in AgCl due to soft-soft (Pearson's principle) affinity.

Systematic comparison of high-throughput single-cell RNA-seq methods for immune cell profiling.

BACKGROUND: Elucidation of immune populations with single-cell RNA-seq has greatly benefited the field of immunology by deepening the characterization of immune heterogeneity and leading to the discovery of new subtypes. However, single-cell methods inherently suffer from limitations in the recovery of complete transcriptomes due to the prevalence of cellular and transcriptional dropout events. This issue is often compounded by limited sample availability and limited prior knowledge of heterogeneity, which can confound data interpretation. RESULTS: Here, we systematically benchmarked seven high-throughput single-cell RNA-seq methods. We prepared 21 libraries under identical conditions of a defined mixture of two human and two murine lymphocyte cell lines, simulating heterogeneity across immune-cell types and cell sizes. We evaluated methods by their cell recovery rate, library efficiency, sensitivity, and ability to recover expression signatures for each cell type. We observed higher mRNA detection sensitivity with the 10x Genomics 5' v1 and 3' v3 methods. We demonstrate that these methods have fewer dropout events, which facilitates the identification of differentially-expressed genes and improves the concordance of single-cell profiles to immune bulk RNA-seq signatures. CONCLUSION: Overall, our characterization of immune cell mixtures provides useful metrics, which can guide selection of a high-throughput single-cell RNA-seq method for profiling more complex immune-cell heterogeneity usually found in vivo.

Indirect evaluation of pit and fissure sealants: A 3D-based method validation.

BACKGROUND: The aim of the present study was to compare indirect methods to assess the clinical performance of pit and fissure sealants and validate the use of 3D scanners. MATERIAL AND METHODS: Sample consisted of 58 plaster models of upper and lower first permanent molars, sealed with resin sealants, as well as photographs obtained during the 18-month follow-up. Pre-established criteria were applied to categorize the sealant presence/absence and marginal integrity. Two calibrated examiners performed the evaluations, independently, using Scanning Electron Microscopy (SEM; gold-standard), Photography, 3D (CEREC In Lab) and Stereomicroscope analysis. RESULTS: The intra-examiner Spearman correlation was 94% e 97%, respectively, and the inter-examiner was 96%. Data was submitted to Kappa test, Spearman correlation and Receiver Operating Characteristic Curve (ROC). 3D and SEM presented good concordance; Stereomicroscope showed regular concordance with SEM and 3D (p<0.001). There was no concordance among Photography and the other methods (p>0.05). SEM had a significant positive correlation with 3D and Stereomicroscope (r=0.76 and 0.71, respectively; p<0.01). There was significant positive correlation (r=0.65) between 3D and Stereomicroscope (p<0.01). The ROC estimated curve areas for Stereomicroscope and 3D were 0.90 (IC:0.81-0.99) and 1.0 (IC:1.0-1.0), respectively (p<0.001). CONCLUSIONS: Photography presented lower sensitivity and specificity (area=0.59). 3D method showed the best performance when compared to gold standard, exhibiting high sensitivity and specificity, therefore, it was validated as a reliable method to evaluate pit and fissure sealants. Key words:Photography, stereomicroscope, SEM, diagnostic, sealants.

Synthesis and Characterization of an SWCNT@HKUST-1 Composite: Enhancing the CO2 Adsorption Properties of HKUST-1.

Synthesis of a new HKUST-1 composite based on single-walled carbon nanotubes (SWCNTs) was successfully achieved (SWCNT@HKUST-1). SWCNTs were used as templates to grow rod-like HKUST-1 crystals over the surface of the nanotubes. N2 adsorption properties showed an increment on the surface area and pore volume for the SWCNT@HKUST-1 composite. Furthermore, the CO2 capture increased, from 7.92 to 8.75 mmol g-1 at 196 K up to 100 kPa, for the SWCNT@HKUST-1 composite. This enhancement was directly associated with the increase of the surface area of the composite. Additionally, an increase in the CO2 heat of adsorption was estimated, from 30 to 39.1 kJ mol-1 for the SWCNT@HKUST-1 composite. In situ Raman experiments corroborated the favored CO2 adsorption for the composite and provided an insight into the augmented hydrophobicity of the SWCNT@HKUST-1. Ethanol adsorption isotherms corroborated an increase in the hydrophobicity of the material upon the incorporation of carbon nanotubes.

A multifactorial approach of nutritional, intellectual, brain development, cardiovascular risk, socio-economic, demographic and educational variables affecting the scholastic achievement in Chilean students: An eight- year follow-up study.

The aim of this study was to quantitate the relative impact of nutritional, intellectual, brain development, cardiovascular risk, socio-economic, demographic and educational variables on the results of the 2009 Quality Education Measurement System (SIMCE) tests of language and mathematics for scholastic achievement (SA) applying a multifactorial approach, in school-age children of the 2010 5th elementary school grade (5ESG) and of the 1st grade of high school (1HSG). The purposes were: i) to test the hypothesis that intellectual ability, the level of SA of the educational establishments in the 2009 SIMCE tests, sex, parental schooling levels, and head circumference-for-age Z-score are the most relevant parameters associated with 2009 SIMCE outcomes; ii) to determine the predictive ability of the 2009 SIMCE results in determining the 2013 SIMCE outcomes for the 2010 5ESG cohort (when they graduated from elementary school, 8th grade) and for determining the 2013 University Selection Test (PSU) outcomes for the 2010 1HSG group (for university admission, when they graduated from high school, 4th grade); iii) to determine the association between the 2009 SIMCE results with the 2017 PSU outcomes for the 2010 5ESG group (for university admission, when they graduated from high school, 4th grade). A representative, proportional and stratified sample of 33 schools of the Metropolitan Region of Chile was randomly chosen. In these schools, 1,353 school-age children of both sexes, of the 2010 5ESG (n = 682; mean age = 10.8 years, SD = 0.6) and of the 2010 1HSG (n = 671; mean age = 14.8 years, SD = 0.6) participated. In both grades and tests, the findings confirm the hypotheses formulated. 2009 SIMCE outcomes were positively and significantly associated with 2013 SIMCE and with 2017 PSU and, with 2013 PSU outcomes in school-age children from 2010 5ESG and 1HSG, respectively. These findings may be useful for educational and health planning in Chile and countries in a comparable stage of development.

Shelf-life kinetic model for freeze-dried oranges using sensory analysis and luminance determination.

Physical (luminance) and sensory variables (color and taste) were used to analyze the aging of freezed-dried oranges slices, determining the influence of temperature and time on aging and evaluating the shelf-life. The highest value in the luminance distribution curve, especially useful when the color of the food products is not uniform, and the color and taste scores obtained in sensory analysis were used to evaluate the shelf-life. Different kinetics models were probed to explain the experimental results but only third-order kinetic model correlated the luminance as a function of time and temperature. This kinetic constant obtained depended on the temperature following an Arrhenius model, giving an activation energy equal to 208 kJ/mol (R2 = 0.9959). The correlation between physical (luminance) and sensory variables (color and taste) may be used to evaluate the shelf life of the orange slices, finding revealed that at 28 °C the shelf life may expected to be 10 years.

Análisis del precio de una dieta saludable y no saludable en la región metropolitana de chile / Comparison of price between a healthy and unhealthy diet in the metropolitan region, chile

La implementación de guías alimentarias basadas en alimentos (GABA) es una estrategia usada por países latinoamericanos para promover una dieta saludable y disminuir las tasas de obesidad.Sin embargo, evidencia sugiere que una alimentación saludable tiene un mayor precio que una no saludable. Nuestro objetivo fue comparar el precio de una dieta saludable (DS) que cumple las GABA chilenascon una dieta no saludable (DNS), y asociar su precio con la densidad energética en la Región Metropolitana (RM) de Chile. La DS fue obtenida del libro “Cocina saludable: cómo incluir 5 porciones de frutas y verduras por día”,publicación oficial del Gobierno de Chile que describe un menú mensual que cumple con las GABA chilenas. La DNS se obtuvo al remplazar preparaciones en la DS por alimentos envasados o preparaciones de consumo típico en Chile. Los precios de alimentos fueron calculados a partir de bases de datos gubernamentales y de supermercados en línea para la RM de Chile. En comparación con la DS, la DNS presenta una menor calidad de alimentación y es hipercalórica con un mayor aporte de energía proveniente de grasas. Nuestros resultados indicanuna relación inversa entre densidad calórica y precio de grupos alimentarios y un mayor precio de la DS en comparación con la DNS. Estos resultados sugieren que una DS dieta que cumple con las GABA chilenas tiene un mayor precio, lo que podría limitar su implementación y la transición hacia patrones de alimentación saludables en laRM de Chile(AU)

. Comparison of price between a healthy and un healthy diet in the Metropolitan Region, Chile. Obesity remains a serious public health problem worldwide and in Latin America. The implementation of dietary guidelines is a strategy used in Chile and other Latin-American countries to promote healthy eating habits. Evidence from studies in US and Europe suggests that healthy eating patterns have a higher price compared to unhealthy food options. However, this has not been evaluated in Chile. Our goal was to compare the price and relation to energetic density of a healthy diet (HD) that follows the Chilean dietary with an unhealthy diet (UD) in the Metropolitan Region (MR), the most densely populated demographical division in Chile. The HD was obtained from the publication “Cocinasaludable: cómoincluir 5 porciones de frutas y verduras por día”, a book of recipessponsored by theChilean governmentto promote intake of fruits and vegetables that fulfills the Chilean dietary guidelines. The UD was obtained by replacing recipesand food items from the DS with processed foods and recipes typically consumed in Chile. The price database was compiled from databases of the Chilean Government and online retailers at MR. The UD has higher energy density, has higher energy from fats and a lower healthy eating index compared with the HD. Price analysis indicated an inverse relation between caloric density and price for food groups and that the UD has an overall lower price compared to the HD. Our results suggest that the higher price of a HD in compliance with the Chilean dietary guidelines could hinder their implementation in the MR, and the transition towards healthy eating habits among its population(AU)

Incremental value of B-type natriuretic peptide for early risk prediction of infective endocarditis.

BACKGROUND: Early and accurate risk prediction is an unmet clinical need in patients with infective endocarditis (IE). The aim of this study was to determine the value of B-type natriuretic peptide (BNP) levels obtained on admission for the prediction of in-hospital death in IE patients. METHODS: Between 2009 and 2011, consecutive patients with IE diagnosed using the revised Duke criteria and admitted to the emergency department were evaluated prospectively. BNP levels were measured on admission. Death during hospitalization was the primary endpoint. RESULTS: Among 104 consecutive patients with IE and with available BNP levels, 34 (32.7%) died in hospital. BNP levels were significantly higher in patients who died as compared to survivors (709.0 pg/ml vs. 177.5 pg/ml, p<0.001). The accuracy of BNP to predict death as quantified by the area under the receiver operating characteristics curve was 0.826 (95% confidence interval (CI) 0.747-0.905). The value of BNP was additive to that provided by clinical, microbiological, and echocardiography assessment. On multivariate analysis, new heart failure (hazard ratio (HR) 2.02, 95% CI 1.15-3.57, p=0.015), sepsis (HR 2.10, 95% CI 1.25-3.55, p=0.005), Staphylococcus aureus endocarditis (HR 2.67, 95% CI 1.60-4.45, p<0.001), left ventricular ejection fraction ≤55% (HR 1.63, 95% CI 1.00-2.65, p=0.047), and BNP (HR 1.04, 95% CI 1.02-1.06, p<0.001) were independent predictors of in-hospital mortality. CONCLUSION: Among patients with IE, BNP levels obtained on admission provide incremental value for early and accurate risk prediction.

Community-acquired culture-negative endocarditis: clinical characteristics and risk factors for mortality.

OBJECTIVES: We studied the clinical characteristics, in-hospital mortality, and long-term prognosis of patients with culture-negative endocarditis. METHODS: In total, 221 episodes of definite endocarditis were studied (2004-2009). We compared the clinical, laboratory, and echocardiography characteristics and the survival rates of patients with culture-negative and culture-positive endocarditis. Survival after hospital discharge was evaluated using the Kaplan-Meier method and coefficient of mortality comparisons. RESULTS: Culture-negative endocarditis occurred in 51/221 (23.1%) episodes. Compared with the culture-positive endocarditis patients, the time elapsed between admission and initiation of antibiotic therapy was longer in patients with culture-negative endocarditis (p<0.001), and these patients also had lower C-reactive protein levels at admission (p<0.001). In-hospital mortality rates were not different between culture-negative and culture-positive patients. After hospital discharge, there was also no significant difference between groups in survival curves (p=0.471). Severe sepsis (adjusted prevalence ratio 3.32, p=0.010) and diabetes mellitus (adjusted prevalence ratio 2.32, p=0.009) were independently associated with in-hospital death in culture-negative patients. CONCLUSIONS: Culture-negative endocarditis patients presented with lower levels of C-reactive protein at admission and required more time for initiation of antibiotic therapy, although there was no difference in in-hospital mortality or long-term survival between culture-negative and culture-positive endocarditis patients. Diabetes mellitus and severe sepsis were associated with in-hospital death in patients with culture-negative endocarditis.

Somatotype and intellectual ability (Raven Progressive Matrices Test) in Chilean school-age children.

OBJECTIVES: The aim of this study was to determine the relationship between somatotype and intellectual ability (IA) in 11-12 and 15-16 year-old students (n = 1,015) in the Chile's Metropolitan Region from a representative sample of 33 educational establishments chosen at random. METHODS: The Heath-Carter somatotype and the IA assessed through the Raven Progressive Matrices Test were measured. RESULTS: The endomorph was observed in 59% of the students; 28% had a mesomorph and 13% ectomorph. The IA was distributed in: 11.2% Grade I, 26.8% Grade II, 41% Grade III, 17.6% Grade IV and 3.2% Grade V. A positive and significant correlation of IA with the endomorphic component (r = 0.074, p = 0.02) was found in the total sample and only in females (r = 0.109, p = 0.02); at the same time, a positive and significant correlation with the ectomorph component was also observed (r = 0.067, p < 0.05). CONCLUSIONS: This suggests that other variables would influence more strongly the IA for which further research is needed to quantitate this multifactorial problem.

Objetivos: El objetivo de este estudio fue determinar la relación entre el somatotipo y la habilidad intelectual (HA) en estudiantes de 11-12 y 15-16 años de edad de la Región Metropolitana, Chile. Métodos: Se registró una muestra representativa de 1.015 escolares de acuerdo a los resultados del sistema de medición de la calidad de la educación (SIMCE) 2009. Se evaluó el somatotipo de Heath-Carter y la HA de acuerdo al Test de Matrices Progresivas de Raven. Resultados: Un 59% presentó un somatotipo endomórfico, 28% mesomórfico y 13% ectomorfo. La HA se distribuyó en: 11,2% Grado I, 26,8% Grado II, 41% Grado III, 17,6% Grado IV y 3,2% Grado V. Se presenta una correlación significativa positiva con el componente endomórfico (r = 0,074 p = 0,02), y sólo en mujeres (r = 0,109 p = 0,02), a la vez se observa una relación significativa positiva con el componente ectomorfo (r = 0,067 p < 0,05). Conclusiones: Esto sugiere que otras variables estarían influyendo más fuertemente en la HA, además de apoyar la no discriminación por biotipo en los establecimientos educacionales.

Effect of immediate or delayed light activation on curing kinetics and shrinkage stress of dual-cure resin cements.

OBJECTIVES: This study evaluated the effect of light activation (absence, immediate, or delayed) on conversion kinetics and polymerization stress of three commercial dual-cured resin cements (Enforce, RelyX ARC, and Panavia F). METHODS: Degree of conversion (DC) was monitored for 30 minutes using real-time near­Fourier transform infrared spectroscopy. The cement was mixed, placed on the spectrometer sample holder, and light activated either immediately or after five minutes (delayed light activation). When no light activation was performed, the materials were protected from light exposure (control). DC was evaluated at five and 30 minutes postmixture. Maximum rates of polymerization (Rp(max)) were obtained from the first derivative of the DC vs time curve. Polymerization stress was monitored for 30 minutes in 1-mm-thick specimens inserted between two cylinders attached to a universal testing machine. Data were submitted to analysis of variance/Tukey tests (α=0.05). RESULTS: Immediate light activation promoted the highest DC at five minutes. At 30 minutes, only RelyX ARC did not present a significant difference in DC between activation modes. Enforce and Panavia F presented higher Rp(max) for immediate and delayed light-activation, respectively. RelyX ARC showed similar Rp(max) for all activation modes. The absence of light activation resulted in the lowest stress followed by delayed light activation, while immediate light activation led to the highest values. RelyX ARC showed higher stress than Enforce, while the stress of Panavia F was similar to that of the others. CONCLUSION: Delayed light activation reduced the polymerization stress of the resin cements tested without jeopardizing DC.

Activation mode effects on the shear bond strength of dual-cured resin cements.

OBJECTIVES: This study evaluated the immediate (10-minute) and delayed (24-hour) bond strength of dual-cured resin cements that are light-activated either immediately or delayed (after five minutes) or chemically-activated only. MATERIALS AND METHODS: Three dual-cured resin cements were evaluated: RelyX ARC, Panavia F and Enforce. Cylinders of resin cement were built up over resin composite blocks following the manufacturers' instructions for each luting agent. The cements were mixed, inserted into the molds and light-activated either immediately or after five minutes (delayed light activation). When no light activation was performed, the materials were protected from light exposure until testing. Half of the samples were tested at 10 minutes; the remaining samples were stored at 100% relative humidity for 24 hours when they were then tested (n = 10). Data were submitted to three-way ANOVA and post-hoc Tukey's tests (alpha = 0.05). The failure mode was evaluated under SEM. RESULTS: RelyX ARC presented the highest values of shear bond strength, followed by Enforce. Panavia F showed the lowest values. Both immediate and delayed light activation caused the cements to present the highest means of shear bond strength. There was an improvement in bond strength after 24 hours of storage. CONCLUSIONS: RelyX ARC produced the highest bond strength, which was improved by light activation and storage for 24 hours.

A novel CD93 polymorphism in non-obese diabetic (NOD) and NZB/W F1 mice is linked to a CD4+ iNKT cell deficient state.

In the present study, we characterize a polymorphism in the CD93 molecule, originally identified as the receptor for the C1q complement component (i.e., C1qRp, or AA4.1) in non-obese diabetic (NOD) mice. This allele carries a coding polymorphism in the first epidermal growth factor-like domain of CD93, which results in an amino acid substitution from Asn-->His at position 264. This polymorphism does not appear to influence protein translation or ecto-domain cleavage, as CD93 is detectable in bone-marrow-derived macrophage and B-cell precursor lysates and in soluble form in the serum. The NOD CD93 isoform causes a phenotypic aberrancy in the early B-cell developmental stages (i.e., pro-, pre-, immature, and transitional), likely related to a conformational variation. Interestingly, the NZB/W F1 strain, which serves as a murine model of Lupus, also expresses an identical CD93 sequence polymorphism. Cd93 is located within the NOD Idd13 locus and is also tightly linked to the NZB/W F1 Wbw1 and Nkt2 disease susceptibility loci, which are thought to regulate natural killer T (NKT) cell homeostasis. Consistent with this genetic linkage, we found B6 CD93(-/-) and B6.NOD(Idd13) mice to be susceptible to a profound CD4(+) NKT cell deficient state. These data suggest that Cd93 may be an autoimmune susceptibility gene residing within the Idd13 locus, which plays a role in regulating absolute numbers of CD4(+) NKT cells.

indicación y uso de corticoides inhalados en el manejo de asma en niños en el Instituto Nacional de Salud del Niño / Indication and use of corticoides inhaled in the managing asthma in children in the National Institute of Health of the Child

Objetivo: Conocer la frecuencia de la indicación de corticoides inhalados para el manejo de asma crónica en niños atendidos en el INSN. Método: estudio descriptivo transversal, se encuestaron 143 pacientes en la Unidad de Asma y Consultorios de Pediatría del INSN en el mes de noviembre de 2010. Resultados: En este trabajo se encontró que 112 (78.3 por ciento) de los pacientes con diagnóstico de asma bronquial, tienen indicación de uso de corticoides inhalados. El corticoides inhalado más frecuente usado en la Unidad de Asma y Consultorios de Pediatría del INSN es la Budesonida de 200 ug, 61 pacientes (54.5 por ciento)...

Objetive: To determine the frequency of inhaled corticosteroid indicated for the management of chronic asthma in children treated at the INSN. method: cross sectional study, 143 patients were surveyed in the Unit of Asthma and in the Pediatrics Clinics of the INSN in November 2010. Results: This study found that 112 (78. 3 per cent) patients diagnosed with bronchial asthma, it is an indication of use of inhaled corticosteroids. The most frequently used inhaled corticosteroids in the Unit of Asthma and pediatric clinics of INSN is Budesonide of 200ug, in 61 patients (54,5 per cent)...

Variability of shear and microtensile bond strength tests to enamel and dentin / Variabilidade de testes de cisalhamento e microtração ao esmalte e à dentina

Purpose: This study aimed to provide guidelines about the coefficient of variation (CV) of shear (SBS) and microtensile (µTBS) bond strength to enamel and dentin. Methods: A search of the English language peer-reviewed literature was conducted using the PubMed database from 2000 to 2009. Only bond strength studies (SBS and µTBS) that have tested both enamel and dentin substrates were selected. The following information was gathered from the 103 papers selected: groups mean and standard deviation (SD), repetition number, and type of statistical analysis. The CV of each study was calculated by using its mean and SD values, the normality of shear and microtensile CV was analyzed using Shapiro-Wilk test, and a CV classification was established for each variable. Results: According to the CV classification proposed, values below 10.3% and 11.3% could be considered low for shear bond strength to enamel and dentin, respectively; and values below 15.4% to enamel and 16.4% to dentin could be considered low for the microtensile test. Values higher than 46.8% and 62.1% (shear bond strength to enamel and dentin) and 45.9% and 45.5% (microtensile bond strength to enamel and dentin) showed a very high variability. Conclusion: Such classification can be useful for future experiments on adhesive materials to estimate statistical power and data precision.

Objetivo: Este estudo se propôs a fornecer diretrizes sobre o coeficiente de variação (CV) de ensaios de resistência ao cisalhamento (SBS) e à microtração (µTBS) em esmalte e dentina.Metodologia: Uma busca de artigos publicados de 2000 a 2009 foi realizada na base de dados PubMed. Apenas estudos (SBS e µTBS) que testaram esmalte e dentina foram considerados elegíveis. As seguintes informações foram coletadas dos 103 artigos selecionados: média e desvio-padrão (DP) dos grupos, número de repetições e análise estatística. O CV de cada estudo foi calculado utilizando-se média e DP, a normalidade dos CV de cada teste foi analisada pelo teste de Shapiro-Wilk e classificações para os CV foram estabelecidas. Resultados: De acordo com a classificação proposta, valores menores que 10,3% e 11,3% são baixos para estudos de cisalhamento ao esmalte e dentina, respectivamente. Para estudos de microtração, baixa variabilidade é obtida com CV menores que 15,4% (esmalte) e 16,4% (dentina). Experimentos com CV maiores que 46,8% e 62,1% (cisalhamento no esmalte e dentina) e 45,9% e 45,5% (microtração no esmalte e na dentina) apresentam variabilidade muito alta. Conclusão: Esta classificação pode ser útil para futuros experimentos em Odontologia adesiva para estimar o poder estatístico dos testes e a precisão dos dados.

The effect of in-office in combination with intracoronal bleaching on enamel and dentin bond strength and dentin morphology.

AIM: The aim of this study was to evaluate in vitro effects of the combination of in-office and intracoronal bleaching on enamel and dentin bond strength and on dentin morphology. METHODS AND MATERIALS: Bleaching treatment was performed on 128 bovine teeth for three weeks. Intracoronal bleaching was performed in groups G1 to G3, and in the other groups a combination of in-office and intracoronal bleaching was performed. The following agents and materials were used (n=16): G1- sodium perborate and water (SP); G2- 37% carbamide peroxide (CP); G3- 35% hydrogen peroxide (HP); G4- HP + cotton pellet soaked in water (CPW); G5- HP + SP; G6- HP + CP; G7- HP + HP; and G8- CPW (control). Seven days after bleaching treatment the teeth were sectioned into two halves. One half of each tooth was ground to obtain a flat dentin surface. Dentin and enamel fragments were treated with a dentin/enamel resin adhesive. Resin composite was inserted in two increments and polymerized for 20 seconds. Following the restorative procedures, specimens were sectioned into beams with a rectangular cross-sectional area of approximately 1 mm2. Microtensile testing was performed in a universal testing machine. Bond strengths (in MPa) were calculated and the data were submitted to an analysis of variance (ANOVA) and the Tukey test (a=0.05). For the scanning electron microscopy (SEM) observation, the exposed pulp chambers (n=5) were fixed, dehydrated, dried in a Critical Point dryer, and gold-sputter coated for analysis at standardized magnifications (500X, 1000X, and 2000X). RESULTS: None of the bleaching techniques reduced the enamel bond strength, the best results observed were with the intracoronal treatments with SP and HP. In dentin all bleaching techniques reduced the bond strength with the exception of the in-office HP application technique. The SEM results demonstrated similar dentin surfaces for the G1, G3, G6, and G7 groups with more open dentin tubules found than in the other groups. CONCLUSION: None of the bleaching techniques tested reduced the bond strength of enamel, but they all reduced the bond strength of dentin with the exception of the group only treated with in-office bleaching using 35% HP. The worst bond strength results to dentin were observed in groups that received intracoronal bleaching with SP.