Application of nanosilica in the construction industry: A bibliometric analysis using Methodi Ordinatio.

The number of publications related to the implementation of nanotechnology in the construction industry, and specifically to the application of nanosilica (SiO2), has had a constant increase in recent years. Based on this, in the present work, an analysis was carried out using bibliometric techniques, with the aim at characterizing the development of specialized literature and identifying the largest areas of growth in the field, maintaining hydrophobic nanosilica as the research guideline. This analysis acquired information from the Scopus and Web of Science (WoS) databases to compare bibliometric indicators of the publications. It should be noted that, even though bibliometric analysis is useful to identify the study areas of greatest interest, to complement this work, the implementation of a method that helped in the research process to obtain the most important bibliography was required. This study implemented Methodi Ordinatio, which helped to take a new direction. Therefore, based on this method, a list of articles cataloged and ranked is obtained, which is the basis for integrating the final bibliographic portfolio. •The study applies the Methodi Ordinatio to obtain a portfolio of the most relevant articles to guide the researchers' work.•Insightful information can be obtained using VOSviewer to analyze and visualize metadata of the bibliographic portfolio.•The study demonstrates how the alpha value in the InOrdinatio formula modifies the resulting portfolio.

PICO questions and DELPHI methodology for improving the management of patients with acute hepatic porphyria.

BACKGROUND: Acute hepatic porphyrias (AHPs) are a group of rare diseases that encompasses acute intermittent porphyria, variegate porphyria, hereditary coproporphyria, and 5-aminolaevulinic acid dehydratase deficiency porphyria. Symptoms of AHP are nonspecific which, together with its low prevalence, difficult the diagnosis and follow-up of these patients. MATERIAL AND METHODS: This project used DELPHI methodology to answer PICO questions related to management of patients with AHPs. The objective was to reach a consensus among multidisciplinary porhyria experts providing answers to those PICO questions for improving diagnosis and follow-up of patients with AHP. RESULTS: Ten PICO questions were defined and grouped in four domains: 1. Biochemical diagnosis of patients with AHP. 2. Molecular tests for patients with AHP. 3. Follow-up of patients with AHP. 4. Screening for long-term complications of patients with AHP. CONCLUSIONS: PICO questions and DELPHI methodology have provided a consensus on relevant and controversial issues for improving the management of patients with AHP.

Cannabinoids induce cell death in leukaemic cells through Parthanatos and PARP-related metabolic disruptions.

BACKGROUND: Several studies have described a potential anti-tumour effect of cannabinoids (CNB). CNB receptor 2 (CB2) is mostly present in hematopoietic stem cells (HSC). The present study evaluates the anti-leukaemic effect of CNB. METHODS: Cell lines and primary cells from acute myeloid leukaemia (AML) patients were used and the effect of the CNB derivative WIN-55 was evaluated in vitro, ex vivo and in vivo. RESULTS: We demonstrate a potent antileukemic effect of WIN-55 which is abolished with CB antagonists. WIN-treated mice, xenografted with AML cells, had better survival as compared to vehicle or cytarabine. DNA damage-related genes were affected upon exposure to WIN. Co-incubation with the PARP inhibitor Olaparib prevented WIN-induced cell death, suggesting PARP-mediated apoptosis which was further confirmed with the translocation of AIF to the nucleus observed in WIN-treated cells. Nicotinamide prevented WIN-related apoptosis, indicating NAD+ depletion. Finally, WIN altered glycolytic enzymes levels as well as the activity of G6PDH. These effects are reversed through PARP1 inhibition. CONCLUSIONS: WIN-55 exerts an antileukemic effect through Parthanatos, leading to translocation of AIF to the nucleus and depletion of NAD+, which are reversed through PARP1 inhibition. It also induces metabolic disruptions. These effects are not observed in normal HSC.

Faraday waves on a nematic liquid crystal, and its coupling with Marangoni convection about the thermal phase transition.

Using a linear hydrodynamic theory, we demonstrate that Faraday waves occur in liquid crystalline fluids. The use of already experimentally known material parameters of a N-(4-methoxybenzylidene)-4-butylaniline liquid crystal allows us to confirm and realize the predictions of this theory. It provides the critical wave number and necessary driving acceleration at instability wave onset. Additionally, these observables experience an abrupt change originated by Marangoni convection due to the temperature gradient at the isotropic-nematic phase transition temperature. Correspondingly, the Marangoni number versus temperature also shows a sharp change in the transition temperature.

Comparative 16S rRNA gene sequencing study of subgingival microbiota of healthy subjects and patients with periodontitis from four different countries.

AIM: To investigate the differences between the subgingival microbiota of healthy subjects (HS) and periodontitis patients (PP) from four different countries through a metagenomic approach. MATERIALS AND METHODS: Subgingival samples were obtained from subjects from four different countries. Microbial composition was analysed through high-throughput sequencing of the V3-V4 region of the 16S rRNA gene. The country of origin, diagnosis and clinical and demographic variables of the subjects were used to analyse the microbial profiles. RESULTS: In total, 506 subgingival samples were analysed: 196 from HS and 310 from patients with periodontitis. Differences in richness, diversity and microbial composition were observed when comparing samples pertaining to different countries of origin and different subject diagnoses. Clinical variables, such as bleeding on probing, did not significantly affect the bacterial composition of the samples. A highly conserved core of microbiota associated with periodontitis was detected, while the microbiota associated with periodontally HS was much more diverse. CONCLUSIONS: Periodontal diagnosis of the subjects was the main variable explaining the composition of the microbiota in the subgingival niche. Nevertheless, the country of origin also had a significant impact on the microbiota and is therefore an important factor to consider when describing subgingival bacterial communities.

Myocardial Wringing and Rigid Rotation in Cardiac Amyloidosis.

Background: The motion of the heart is a result of the helicoidal arrangement of the myofibers in the organ's wall. We aimed to study the relationship between the wringing motion state and the degree of ventricular function in patients with cardiac amyloidosis (CA). Methods: Fifty patients with CA and decreased global longitudinal strain (LS) were evaluated using 2-dimensional speckle-tracking echocardiography. We have expressed LS as positive values to facilitate understanding. Normal twist, which occurs when basal and apical rotations occur in opposite directions, was coded as positive. When the apex and base rotate in the same direction (rigid rotation), twist was coded as negative. Left ventricular (LV) wringing (calculated as twist/LS, which takes into account actions that occur simultaneously during LV systole [ie, longitudinal shortening and twist]) was evaluated according to LV ejection fraction (LVEF). Results: Most of the patients (66%) who participated in the study were diagnosed with transthyretin amyloidosis. A positive relationship was observed between wringing and LVEF (r = 0.75, P < 0.0001). In advanced stages of ventricular dysfunction, rigid rotation appeared in 66.6% of patients with LVEF ≤ 40%, in whom negative values of twist and wringing were observed. LV wringing proved to be a good discriminator of LVEF (area under the curve 0.90, P < 0.001, 95% confidence interval 0.79-0.97); for example, wringing < 1.30°/% detected LVEF < 50% with 85.7% sensibility and 89.7% specificity. Conclusions: Wringing, which integrates twist and simultaneous LV longitudinal shortening, is a conditioning rotational parameter of the degree of ventricular function in patients with CA.

Contexte: Les mouvements du cœur sont le résultat de l'orientation hélicoïdale des fibres des parois du cœur. L'objectif de notre étude était d'étudier le lien entre le mouvement « d'essorage ¼ et la fonction ventriculaire chez les patients atteints d'amylose cardiaque (AC). Méthodologie: Cinquante patients atteints d'AC et présentant une déformation longitudinale (DL) globale réduite ont fait l'objet d'une évaluation à l'aide de l'échocardiographie bidimensionnelle de suivi des marqueurs acoustiques. Nous avons choisi d'exprimer la DL en valeurs positives pour faciliter la compréhension des données. Une torsion normale, caractérisée par les mouvements de rotation opposés entre la base et l'apex du cœur, a été codée comme positive. Lorsque l'apex et la base opéraient une rotation dans la même direction (rotation rigide), la torsion était codée comme négative. Le mouvement « d'essorage ¼ du ventricule gauche (VG) (calculé comme le rapport torsion/DL, qui tient compte des actions survenant simultanément durant la systole du VG [c.-à-d., raccourcissement longitudinal et torsion]) a été évalué en fonction de la fraction d'éjection du VG (FEVG). Résultats: La plupart des patients (66 %) ayant participé à l'étude avaient reçu un diagnostic d'amylose à transthyrétine. Un lien positif a été établi entre le mouvement d'essorage et la FEVG (coefficient de corrélation [r] = 0,75, p < 0,0001). Aux stades avancés de la dysfonction ventriculaire, une rotation rigide a été observée chez 66,6 % des patients ayant une FEVG ≤ 40 % et chez qui les valeurs de torsion et d'essorage étaient négatives. L'essorage du VG s'est révélé être un facteur fiable de détermination de la FEVG (aire sous la courbe : 0,90; p < 0,001, intervalle de confiance [IC] à 95 % : 0,79-0,97); par exemple, un mouvement d'essorage < 1,30 °/% a permis de détecter une FEVG < 50 % avec une sensibilité de 85,7 % et une spécificité de 89,7 %. Conclusions: Le mouvement d'essorage, qui intègre simultanément la torsion et le raccourcissement longitudinal du VG, est un paramètre rotationnel qui influence le degré de fonction ventriculaire chez les patients atteints d'AC.

Tamizaje auditivo universal neonatal en Hospital Clínico La Florida Dra. Eloísa Díaz Insunza: Experiencia 2015-2021 / Universal newborn hearing screening at Hospital Clínico La Florida Dra. Eloísa Díaz Insunza: Experience 2015-2021

Introducción: La hipoacusia congénita es una patología frecuente entre los recién nacidos con gran impacto en su calidad de vida si no es diagnosticada y tratada precozmente. Para su pesquisa, se recomienda, internacionalmente, el tamizaje auditivo universal neonatal (TAUN), que desde 2014 se aplica en el Hospital Clínico La Florida Dra. Eloísa Díaz Insunza (HLF). Objetivo: Describir la experiencia del programa de TAUN del Servicio de Otorrinolaringología HLF. Material y Método: Estudio descriptivo, retrospectivo. Se incluyó a todos los recién nacidos vivos (RNV) del establecimiento entre 2015 y 2021, evaluados de acuerdo con el protocolo del programa. Resultados: Fueron evaluados 17.804 RNV. Se obtuvo una cobertura de 97,1% y tasa de referencia de 0,98%. Se confirmaron a 21 pacientes con hipoacusia sensorioneural (HSN), obteniéndose una tasa de HSN de 1,5 cada 1.000 RNV. Conclusión: La tasa de incidencia de HSN congénita fue similar a la estimada a nivel mundial. El programa de TAUN HLF cumple con estándares internacionales en cuanto a cobertura, tiempo de evaluación del tamizaje y tasa de referencia. El trabajo multidisciplinario, mejoría de tecnología y registro adecuado de pacientes, son las principales fortalezas. La dificultad de seguimiento durante horario inhábil y presencia de sólo un profesional con dedicación exclusiva, son aspectos a perfeccionar.

Introduction: Congenital hearing loss is a frequent pathology among newborns with great impact on their quality of life if it is not diagnosed and treated early. The Joint Committee on Infant Hearing recommends universal newborn hearing screening (UNHS) and has been applied at the Hospital Clínico La Florida Dra. Eloísa Díaz Insunza (HLF) since 2014. Aim: To describe the experience of UNHS program at the Otolaryngology Service of the HLF. Material and Method: Descriptive, retrospective study, including all newborns of the HLF between 2015 and 2021. They were evaluated according to the protocol proposed in the program. Results: 17804 newborns were evaluated. Coverage of 97,1% and a referral rate of 0,98% were obtained. Twenty-one patients with sensorineural hearing loss (SNHL) were confirmed, obtaining a SNHL rate of 1.5 per 1000 live births. Conclusion: The incidence rate of congenital SNHL is similar to that estimated worldwide. The UNHS program in HLF complies with international standards in terms of coverage, timing and referral rates. Multidisciplinary work, improved technology and adequate patient registration are the main strengths of the program. The difficulty of follow-ups during the weekends and the presence of only one full-time professional are aspects that can be improved.

Proteome alterations during clonal isolation of established human pancreatic cancer cell lines.

Clonal isolation is an integral step of numerous workflows in genome editing and cell engineering. It comprises the isolation of a single progenitor cell from a defined cell line population with subsequent expansion to obtain a monoclonal cell population. This process is associated with transient loss of cell-cell contacts and absence of a multicellular microenvironment. Previous studies have revealed transcriptomic changes upon clonal isolation with cell line specific extent. Since transcriptome alterations are only partially reflected on the proteome level, we sought to investigate the impact of clonal isolation on the cellular proteome to a depth of > 6000 proteins in three established pancreatic cancer cell lines. We show that clonal isolation does have an impact on the cellular proteome, however, with cell line specific extent, affecting different biological processes, and also depending on the isolation method. We demonstrate a different impact of clonal isolation on mesenchymal- and epithelial-derived cell lines mainly affecting cell proliferation, metabolism, cell adhesion and cellular stress. The results bear relevance to the field of genomic editing and cell engineering and highlight the need to consider the impact of clonal isolation when interpreting data stemming from experiments that include this step.

Efectos de un programa de rehabilitación remota en atención primaria en salud, posterior al alta hospitalaria por COVID-19: estudio observacional / Effects of a remote rehabilitation program in primary health care, after hospital discharge due to COVID-19: observational study

Se ha reportado un importante daño sistémico de los pacientes afectados por COVID-19, y aún existen interrogantes sobre las secuelas a largo plazo. Surge ante esto la necesidad de plantear programas de rehabilitación de los sistemas primarios de atención, que respondan a estas necesidades. Se realizó un programa de 6 semanas de rehabilitación remota, con seguimiento y progreso semanal, posterior al alta hospitalaria por COVID-19 a 114 usuarios de 4 centros de atención primaria de la comuna de El Bosque, Santiago, R. Metropolitana. Se incluyó a pacientes de edades entre 21 y 93 años, combinando los principios del ejercicio terapéutico individualizado, una evaluación presencial previo y posterior a las 6 semanas de trabajo. Los indicadores evaluados fueron: Minimental Abreviado, 1 Minute Sit to Stand Test (1min STST), Timed Up and Go (TUG), índice de Barthel y FRAIL. Se hicieron análisis inferenciales y descriptivos y se encontraron mejoras favorables en los indicadores de condición física (TUG y 1'STST), Índice de Barthel y el Simple "FRAIL" Questionnaire Screening Tool (FRAIL). En conclusión, si bien la mayoría de los indicadores tuvieron resultados favorables, es necesario seguir estudiando herramientas de evaluación más sensibles e intervenciones específicas que se adapten a las necesidades de las personas.

Significant systemic damage has been reported in patients affected by COVID-19, and questions remain about long-term sequelae. Therefore, the need arises to propose rehabilitation programs for primary care systems that respond to these needs. A 6-week program of remote rehabilitation, with weekly follow-up and progress, after hospital discharge for COVID-19 was carried out on 114 users from 4 primary care centers in the commune of El Bosque, Santiago, Chile. The program included patients from 21 to 93 years-old, combining the principles of individualized therapeutic exercise, a face-to-face evaluation before and after 6 weeks of work. The indicators evaluated were: Abbreviated Minimental, 1 minute Sit to Stand Test (1 min STST), Timed Up and Go (TUG), Barthel index and the Simple "FRAIL" Questionnaire Screening Tool (FRAIL). Inferential and descriptive analyses were carried out and favorable improvements were found in the indicators of physical condition (TUG and 1min STST), Barthel Index and FRAIL. In conclusion, while most of the indicators had favorable results, it is required to further explore more sensitive assessment tools and targeted interventions that are tailored to people's needs.

Efectos de un programa de tele-rehabilitación en la capacidad física y disnea en atención primaria en salud, posterior al alta hospitalaria por COVID-19: estudio observacional / Effects of a tele-rehabilitation program on physical capacity and dyspnea in primary health care, after hospital discharge for covid-19: observational study

Resumen En marzo del año 2020, se declaró una pandemia de características mundiales, por un virus, que genera deterioro importante a nivel sistémico, SARS -CoV-2, con la enfermedad COVID-19. El deterioro funcional de quienes sufren secuelas post COVID-19 ha llevado a los profesionales de la rehabilitación a buscar formas eficientes de intervenir. Este estudio, descriptivo y retrospectivo, evaluó los efectos de un programa de rehabilitación remoto de 6 semanas, en 39 pacientes dados de alta de COVID-19, de un Centro de Salud Familiar (CESFAM) de la Comuna de El Bosque, Santiago, Chile, entre julio y diciembre del año 2020, analizando la capacidad física con el test 1 minuto sentado-de pie y disnea con escala de Borg modificada. Los resultados mostraron cambios estadísticamente significativos en la capacidad física y disnea de los pacientes intervenidos. Es necesario estudiar los beneficios de intervenciones específicas para esta población, y su impacto a largo plazo, entendiendo que convivimos con una nueva enfermedad, un COVID-19 prolongado, que incluso en cuadros leves está dejando secuelas funcionales importantes.

In March 2020, a pandemic of global characteristics was declared, due to a virus, which generates significant deterioration at the systemic level, SARS -CoV-2, with the COVID-19 disease. The functional deterioration of those suffering from post-COVID-19 sequelae has led rehabilitation professionals to look for efficient ways to intervene. This study, descriptive and retrospective, evaluated the effects of a 6-week remote rehabilitation program, in 39 patients discharged from COVID-19, from a Family Health Center in the Commune of El Bosque, Santiago, Chile, between July and December 2020, analyzing physical capacity with the 1 minute sitting-standing test and dyspnea with modified Borg's scale. The results showed statistically significant changes in the physical capacity and dyspnea of the operated patients. It is necessary to study the benefits of specific interventions for this population, and their long-term impact, understanding that we live with a new disease, a prolonged COVID, which even in mild cases is leaving important functional sequelae.

Epidemiologic trend of pediatric inflammatory bowel disease in Latin America: The Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) Working Group.

INTRODUCTION AND AIMS: The primary aim was to explore the epidemiologic trend of pediatric inflammatory bowel disease in Latin America, and the secondary aims were to obtain an overview of the diagnostic/therapeutic focus of the members of the LASPGHAN and examine the relation of case frequency to year, during the study period. MATERIALS AND METHODS: Latin American pediatric gastroenterologists participated in an online survey, conducted through the SurveyMonkey platform, that investigated the yearly frequency of new inflammatory bowel disease patients within the time frame of 2005-2016, their disease variety, the gastrointestinal segments affected, and the diagnostic and treatment methods utilized. The correlation of new case frequency with each study year was evaluated. RESULTS: A total of 607 patients were studied. The diagnoses were ulcerative colitis in 475 (78.3%) cases, Crohn's disease in 104 (17.1%), and inflammatory bowel disease D unclassified in 28 (4.6%). The trend in ulcerative colitis was a lineal increase in the frequency of new cases related to each study year, with a significant correlation coefficient. Pancolitis was found in 67.6% of the patients. The diagnostic methods included clinical data, endoscopy, and biopsies in more than 99% of the cases, and imaging studies were indicated selectively. Drug regimens were limited to 5-aminosalicylic acid derivatives, azathioprine, 6-mercaptopurine, infliximab, and adalimumab. CONCLUSIONS: Pediatric inflammatory bowel disease in Latin America appears to have increased during the years included in the study period, with a predominance of moderate or severe ulcerative colitis. That lineal trend suggests the predictive likelihood of a gradual increase in the coming years, with possible epidemiologic and clinical implications.

A nearby transiting rocky exoplanet that is suitable for atmospheric investigation.

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

Phosphate-Arsenic Interactions in Halophilic Microorganisms of the Microbial Mat from Laguna Tebenquiche: from the Microenvironment to the Genomes.

Arsenic (As) is a metalloid present in the earth's crust and widely distributed in the environment. Due to its high concentrations in the Andean valleys and its chemical similarity with phosphorus (P), its biological role in Andean Microbial Ecosystems (AMEs) has begun to be studied. The AMEs are home to extremophilic microbial communities that form microbial mats, evaporites, and microbialites inhabiting Andean lakes, puquios, or salt flats. In this work, we characterize the biological role of As and the effect of phosphate in AMEs from the Laguna Tebenquiche (Atacama Desert, Chile). Using micro X-ray fluorescence, the distribution of As in microbial mat samples was mapped. Taxonomic and inferred functional profiles were obtained from enriched cultures of microbial mats incubated under As stress and different phosphate conditions. Additionally, representative microorganisms highly resistant to As and able to grow under low phosphate concentration were isolated and studied physiologically. Finally, the genomes of the isolated Salicola sp. and Halorubrum sp. were sequenced to analyze genes related to both phosphate metabolism and As resistance. The results revealed As as a key component of the microbial mat ecosystem: (i) As was distributed across all sections of the microbial mat and represented a significant weight percentage of the mat (0.17 %) in comparison with P (0.40%); (ii) Low phosphate concentration drastically changed the microbial community in microbial mat samples incubated under high salinity and high As concentrations; (iii) Archaea and Bacteria isolated from the microbial mat were highly resistant to arsenate (up to 500 mM), even under low phosphate concentration; (iv) The genomes of the two isolates were predicted to contain key genes in As metabolism (aioAB and arsC/acr3) and the genes predicted to encode the phosphate-specific transport operon (pstSCAB-phoU) are next to the arsC gene, suggesting a functional relationship between these two elements.

Ultrasonic characterization of salt, moisture and texture modifications in dry-cured ham during post-salting.

For the first time, this study addresses the use of non-destructive ultrasound to monitor ham post-salting. For that purpose, the ultrasonic velocity (1 MHz) and the weight loss of hams were measured regularly every 2 days up to 8 weeks after salting. Additionally, for different post-salting times, internal salt and moisture content and hardness were measured at different locations from the ham surface. The experimental results reflected that the ultrasonic velocity increased as the ham weight decreased (26.1 m/s per kg), showing a satisfactory correlation between both variables (r = 0.95). The ultrasonic velocity was also correlated with the salt and moisture content. However, ham hardness remained fairly constant during post-salting, which confirmed that characteristic textural changes mainly occur during the salting and drying-maturation stages. Thus, the ultrasonic velocity could be a reliable parameter with which to monitor not only overall modifications in ham weight, but also internal changes of moisture and salt content during post-salting in a non-destructive way.

Epidemiologic trend of pediatric inflammatory bowel disease in Latin America: The Latin American Society for Pediatric Gastroenterology, Hepatology and Nutrition (LASPGHAN) Working Group. / Tendencia epidemiológica de la enfermedad intestinal inflamatoria en pacientes pediátricos en América Latina: Grupo de Trabajo en Enfermedad Intestinal Inflamatoria, Sociedad Latinoamericana de Gastroenterología, Hepatología y Nutrición Pediátrica (SLAGHNP).

INTRODUCTION AND OBJECTIVES: The primary aim was to explore the epidemiologic trend of pediatric inflammatory bowel disease in Latin America, and the secondary aims were to obtain an overview of the diagnostic/therapeutic focus of the members of the LASPGHAN and examine the relation of case frequency to year, during the study period. MATERIALS AND METHODS: Latin American pediatric gastroenterologists participated in an online survey, conducted through the SurveyMonkey platform, that investigated the yearly frequency of new inflammatory bowel disease patients within the time frame of 2005 to 2016, their disease variety, the gastrointestinal segments affected, and the diagnostic and treatment methods utilized. The correlation of new case frequency with each study year was evaluated. RESULTS: A total of 607 patients were studied. The diagnoses were ulcerative colitis in 475 (78.3%) cases, Crohn's disease in 104 (17.1%), and inflammatory bowel disease D unclassified in 28 (4.6%). The trend in ulcerative colitis was a lineal increase in the frequency of new cases related to each study year, with a significant correlation coefficient. Pancolitis was found in 67.6% of the patients. The diagnostic methods included clinical data, endoscopy, and biopsies in more than 99% of the cases, and imaging studies were indicated selectively. Drug regimens were limited to 5-aminosalicylic acid derivatives, azathioprine, 6-mercaptopurine, infliximab, and adalimumab. CONCLUSIONS: Pediatric inflammatory bowel disease in Latin America appears to have increased during the years included in the study period, with a predominance of moderate or severe ulcerative colitis. That lineal trend suggests the predictive likelihood of a gradual increase in the coming years, with possible epidemiologic and clinical implications.

Magnetic viscoelastic behavior in a colloidal ferrofluid.

Based on the stochastic Langevin equation, we derived the total friction experienced by a tracer particle diffusing in thermally equilibrated colloidal magnetic fluids. This transport property leads to new expressions for its long-time diffusion coefficients, which satisfy an Einstein relation with the frictions of its translational and rotational Brownian motion. Further use of the nano-rheology theory allowed us to derive also the viscoelastic modulus of the colloid from such a property. The temporal relaxation of the viscoelasticity and transport coefficient turns out to be governed by the intermediate scattering function of the colloid. We derived an explicit formula for this evolution function within a hydrodynamic theory to include rotational degrees of freedom of the particles. In the limit of short frequencies, the viscous moduli render a new expression for the static viscosity. We found that its comparison with known experiments, at low and high concentration of ferroparticles in magnetite ferrofluids, is fair. However, comparing the predicted viscoelastic moduli with computer simulations as a function of frequency yields poor agreement.

An epistatic interaction between pre-natal smoke exposure and socioeconomic status has a significant impact on bronchodilator drug response in African American youth with asthma.

BACKGROUND: Asthma is one of the leading chronic illnesses among children in the United States. Asthma prevalence is higher among African Americans (11.2%) compared to European Americans (7.7%). Bronchodilator medications are part of the first-line therapy, and the rescue medication, for acute asthma symptoms. Bronchodilator drug response (BDR) varies substantially among different racial/ethnic groups. Asthma prevalence in African Americans is only 3.5% higher than that of European Americans, however, asthma mortality among African Americans is four times that of European Americans; variation in BDR may play an important role in explaining this health disparity. To improve our understanding of disparate health outcomes in complex phenotypes such as BDR, it is important to consider interactions between environmental and biological variables. RESULTS: We evaluated the impact of pairwise and three-variable interactions between environmental, social, and biological variables on BDR in 233 African American youth with asthma using Visualization of Statistical Epistasis Networks (ViSEN). ViSEN is a non-parametric entropy-based approach able to quantify interaction effects using an information-theory metric known as Information Gain (IG). We performed analyses in the full dataset and in sex-stratified subsets. Our analyses identified several interaction models significantly, and suggestively, associated with BDR. The strongest interaction significantly associated with BDR was a pairwise interaction between pre-natal smoke exposure and socioeconomic status (full dataset IG: 2.78%, p = 0.001; female IG: 7.27%, p = 0.004)). Sex-stratified analyses yielded divergent results for females and males, indicating the presence of sex-specific effects. CONCLUSIONS: Our study identified novel interaction effects significantly, and suggestively, associated with BDR in African American children with asthma. Notably, we found that all of the interactions identified by ViSEN were "pure" interaction effects, in that they were not the result of strong main effects on BDR, highlighting the complexity of the network of biological and environmental factors impacting this phenotype. Several associations uncovered by ViSEN would not have been detected using regression-based methods, thus emphasizing the importance of employing statistical methods optimized to detect both additive and non-additive interaction effects when studying complex phenotypes such as BDR. The information gained in this study increases our understanding and appreciation of the complex nature of the interactions between environmental and health-related factors that influence BDR and will be invaluable to biomedical researchers designing future studies.