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Introduction: Given the ensuing increase in bone and periodontal diseases and defects, de novo bone repair and/or regeneration strategies are constantly undergoing-development alongside advances in orthopedic, oro-dental and cranio-maxillo-facial technologies and improvements in bio-/nano-materials. Indeed, there is a remarkably growing need for new oro-dental functional biomaterials that can help recreate soft and hard tissues and restore function and aesthetics of teeth/ dentition and surrounding tissues. In bone tissue engineering, HydroxyApatite minerals (HAp), the most stable CaP/Calcium Phosphate bioceramic and a widely-used material as a bone graft substitute, have been extensively studied for regenerative medicine and dentistry applications, including clinical use. Yet, limitations and challenges owing principally to its bio-mechanical strength, exist and therefore, research and innovation efforts continue to pursue enhancing its bio-effects, particularly at the nano-scale. Methods: Herein, we report on the physico-chemical properties of a novel nanoHydroxyApatite material obtained from the backbone of Salmon fish (patent-pending); an abundant and promising yet under-explored alternative HAp source. Briefly, our nanoS-HAp obtained via a modified and innovative alkaline hydrolysis-calcination process was characterized by X-ray diffraction, electron microscopy, spectroscopy, and a cell viability assay. Results and Discussion: When compared to control HAp (synthetic, human, bovine or porcine), our nanoS-HAp demonstrated attractive characteristics, a promising biomaterial candidate for use in bone tissue engineering, and beyond.

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ABSTRACT Objective. To provide a comprehensive overview of geographical patterns (2001-2010) and time trends (1993-2012) of cancer incidence in children aged 0-19 years in Latin America and the Caribbean (LAC) and interpret the findings in the context of global patterns. Methods. Geographical variations in 2001-2010 and incidence trends over 1993-2012 in the population of LAC younger than 20 years were described using the database of the third volume of the International Incidence of Childhood Cancer study containing comparable data. Age-specific incidence per million person-years (ASR) was calculated for population subgroups and age-standardized (WSR) using the world standard population. Results. Overall, 36 744 unique cases were included in this study. In 2001-2010 the overall WSR in age 0-14 years was 132.6. The most frequent were leukemia (WSR 48.7), central nervous system neoplasms (WSR 23.0), and lymphoma (WSR 16.6). The overall ASR in age group 15-19 years was 152.3 with lymphoma ranking first (ASR 30.2). Incidence was higher in males than in females, and higher in South America than in Central America and the Caribbean. Compared with global data LAC incidence was lower overall, except for leukemia and lymphoma at age 0-14 years and the other and unspecified tumors at any age. Overall incidence at age 0-19 years increased by 1.0% per year (95% CI [0.6, 1.3]) over 1993-2012. The included registries covered 16% of population aged 0-14 years and 10% of population aged 15-19 years. Conclusions. The observed patterns provide a baseline to assess the status and evolution of childhood cancer occurrence in the region. Extended and sustained support of cancer registration is required to improve representativeness and timeliness of data for childhood cancer control in LAC.

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RESUMO Objetivo. Apresentar uma visão abrangente dos padrões geográficos (2001 a 2010) e das tendências temporais (1993 a 2012) da incidência de câncer em crianças e jovens de 0 a 19 anos na América Latina e no Caribe (ALC) e interpretar os resultados no contexto de padrões mundiais. Métodos. Foram descritas variações geográficas de 2001 a 2010 e tendências de incidência de 1993 a 2012 na população com menos de 20 anos da ALC usando informações comparáveis da base de dados do terceiro volume do estudo International Incidence of Childhood Cancer. Foram calculadas taxas de incidência específica por idade por milhão de pessoas-ano (ASR, na sigla em inglês) para subgrupos populacionais e taxas padronizadas por idade usando a população padrão mundial (WSR, na sigla em inglês). Resultados. No total, foram incluídos 36 744 casos únicos. No período de 2001 a 2010, a WSR para todos os tumores combinados na faixa etária de 0 a 14 anos foi de 132,6. Os diagnósticos mais frequentes foram leucemia (WSR de 48,7), neoplasias do sistema nervoso central (WSR de 23,0) e linfoma (WSR de 16,6). A ASR para todos os tumores combinados na faixa etária de 15 a 19 anos foi de 152,3, e a maior taxa foi a de linfoma (ASR de 30,2). A incidência foi maior no sexo masculino do que no sexo feminino e maior na América do Sul do que na América Central e no Caribe. De modo geral, em comparação com as estimativas mundiais, a incidência na ALC foi menor, exceto para leucemia e linfoma entre 0 e 14 anos e para outros tumores e tumores não especificados em qualquer idade. A taxa de incidência na faixa etária de 0 a 19 anos aumentou em 1,0% ao ano (IC de 95% [0,6, 1,3]) entre 1993 e 2012. Os registros incluídos cobriam 16% da população de 0 a 14 anos e 10% da população de 15 a 19 anos. Conclusões. Os padrões observados servem de referência para avaliar o status e a evolução da ocorrência de câncer infantil na região. É necessário garantir um apoio ampliado e consistente aos registros de câncer para aprimorar a representatividade e a disponibilidade das informações em tempo adequado para o controle do câncer infantil na ALC.

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INTRODUCTION: in patients with anterior glenohumeral (GH) instability together with an off-track or engaging Hill-Sachs (HS) defect, Bankart-remplissage (B-R) surgery reduces the recurrence rate when compared to Bankart (B) surgery alone. There is controversy regarding whether the recurrence rate also decreases in patients with on-track or non-engaging Hill-Sachs defects. OBJECTIVE: to compare the recurrence rate and clinical evolution of patients with anterior glenohumeral instability with 'on-track' Hill-Sachs defect treated with either B or B-R surgery. MATERIAL AND METHODS: non-randomized, retrospective, single-center cohort study of patients with anterior glenohumeral instability and on-track Hill-Sachs defect, operated between January 2010 and December 2018. Patients operated with B versus B-R were compared. Recurrence, complications and re-operation were recorded. In addition, VAS, SSV, WOSI and qDASH scores were obtained and compared in both groups. RESULTS: of the 105 patients who met the inclusion criteria, 78 (74.3%) patients had a complete follow-up (52 B and 26 B-R, 4.3 years median follow-up). There was a higher recurrence rate in group B compared to B-R, with this difference not reaching statistical significance (17.3% vs 7.7%, p = 0.21). There were no significant differences in residual pain, feeling of instability, complications or VAS, qDASH, SSV or WOSI scores between both groups. In the subgroup analysis, patients who practiced contact sports and were operated with B showed higher recurrence rates (24.1% vs 0%, p = 0.08) and complications (41.4% vs 18.2%, p = 0.16) when compared to B + R, although these differences were not significant. CONCLUSION: there were no significant differences in recurrence rates and functional evolution between patients with anterior glenohumeral instability operated with B or B-R surgery. Comparative, prospective studies should be performed to establish definitive recommendations.

INTRODUCCIÓN: en pacientes con inestabilidad glenohumeral (GH) anterior con defecto de Hill-Sachs (HS) off-track o enganchante, Bankart-remplissage (B + R) reduce tasa de recurrencia en comparación a Bankart aislado (B). Hay controversia si tasa de recurrencia también disminuye en pacientes con defecto de HS on-track o no enganchantes. OBJETIVO: comparar la tasa de recurrencia y evolución clínica entre la cirugía de B versus B-R en pacientes operados por inestabilidad glenohumeral anterior con defecto de Hill-Sachs on-track. MATERIAL Y MÉTODOS: estudio de cohorte, no randomizado, retrospectivo y unicéntrico, en pacientes operados por inestabilidad glenohumeral anterior, entre Enero 2010 y Diciembre de 2018. Se incluyen sólo pacientes con defecto de Hill-Sachs on-track. Fueron comparados pacientes operados con cirugía de B versus B + R. Se consigna recurrencia, complicación, reoperación y sensación de inestabilidad. Además, se realizan y comparan puntajes de EVA, SSV, WOSI y qDASH. RESULTADOS: de los 105 pacientes que cumplieron criterios de inclusión, 78 (74.3%) realizaron seguimiento completo (52 B y 26 B + R, 4.3 años mediana de seguimiento). Hubo mayor tasa de recurrencia en grupo B en comparación a B + R, siendo esta diferencia no significativa (17.3% versus 7.7%, p = 0.21). No hubo diferencia significativa en dolor residual, sensación de inestabilidad residual, complicaciones o puntajes de escala EVA, qDASH, SSV ni WOSI. En análisis por subgrupo, pacientes con deportes de contacto, B tienen mayor tasa de recurrencia (24.1% versus 0%, p = 0.08) y complicaciones comparadas con B + R (41.4% versus 18.2%, p = 0.16), siendo estas diferencias no significativas. CONCLUSIÓN: no hubo diferencias significativas en tasa de recurrencia y evolución funcional entre cirugía de Bankart aislado o Bankart-remplissage para inestabilidad glenohumeral anterior asociada a defecto de Hill-Sachs on-track. Estudios comparativos, prospectivos deben realizarse para establecer recomendaciones definitivas.

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Resumen: Introducción: en pacientes con inestabilidad glenohumeral (GH) anterior con defecto de Hill-Sachs (HS) off-track o enganchante, Bankart-remplissage (B + R) reduce tasa de recurrencia en comparación a Bankart aislado (B). Hay controversia si tasa de recurrencia también disminuye en pacientes con defecto de HS on-track o no enganchantes. Objetivo: comparar la tasa de recurrencia y evolución clínica entre la cirugía de B versus B-R en pacientes operados por inestabilidad glenohumeral anterior con defecto de Hill-Sachs on-track. Material y métodos: estudio de cohorte, no randomizado, retrospectivo y unicéntrico, en pacientes operados por inestabilidad glenohumeral anterior, entre Enero 2010 y Diciembre de 2018. Se incluyen sólo pacientes con defecto de Hill-Sachs on-track. Fueron comparados pacientes operados con cirugía de B versus B + R. Se consigna recurrencia, complicación, reoperación y sensación de inestabilidad. Además, se realizan y comparan puntajes de EVA, SSV, WOSI y qDASH. Resultados: de los 105 pacientes que cumplieron criterios de inclusión, 78 (74.3%) realizaron seguimiento completo (52 B y 26 B + R, 4.3 años mediana de seguimiento). Hubo mayor tasa de recurrencia en grupo B en comparación a B + R, siendo esta diferencia no significativa (17.3% versus 7.7%, p = 0.21). No hubo diferencia significativa en dolor residual, sensación de inestabilidad residual, complicaciones o puntajes de escala EVA, qDASH, SSV ni WOSI. En análisis por subgrupo, pacientes con deportes de contacto, B tienen mayor tasa de recurrencia (24.1% versus 0%, p = 0.08) y complicaciones comparadas con B + R (41.4% versus 18.2%, p = 0.16), siendo estas diferencias no significativas. Conclusión: no hubo diferencias significativas en tasa de recurrencia y evolución funcional entre cirugía de Bankart aislado o Bankart-remplissage para inestabilidad glenohumeral anterior asociada a defecto de Hill-Sachs on-track. Estudios comparativos, prospectivos deben realizarse para establecer recomendaciones definitivas.

Abstract: Introduction: in patients with anterior glenohumeral (GH) instability together with an off-track or engaging Hill-Sachs (HS) defect, Bankart-remplissage (B-R) surgery reduces the recurrence rate when compared to Bankart (B) surgery alone. There is controversy regarding whether the recurrence rate also decreases in patients with on-track or non-engaging Hill-Sachs defects. Objective: to compare the recurrence rate and clinical evolution of patients with anterior glenohumeral instability with 'on-track' Hill-Sachs defect treated with either B or B-R surgery. Material and methods: non-randomized, retrospective, single-center cohort study of patients with anterior glenohumeral instability and on-track Hill-Sachs defect, operated between January 2010 and December 2018. Patients operated with B versus B-R were compared. Recurrence, complications and re-operation were recorded. In addition, VAS, SSV, WOSI and qDASH scores were obtained and compared in both groups. Results: of the 105 patients who met the inclusion criteria, 78 (74.3%) patients had a complete follow-up (52 B and 26 B-R, 4.3 years median follow-up). There was a higher recurrence rate in group B compared to B-R, with this difference not reaching statistical significance (17.3% vs 7.7%, p = 0.21). There were no significant differences in residual pain, feeling of instability, complications or VAS, qDASH, SSV or WOSI scores between both groups. In the subgroup analysis, patients who practiced contact sports and were operated with B showed higher recurrence rates (24.1% vs 0%, p = 0.08) and complications (41.4% vs 18.2%, p = 0.16) when compared to B + R, although these differences were not significant. Conclusion: there were no significant differences in recurrence rates and functional evolution between patients with anterior glenohumeral instability operated with B or B-R surgery. Comparative, prospective studies should be performed to establish definitive recommendations.

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INTRODUCTION: Neurocysticercosis (NCC) is the most frequent parasitic disease in the central nervous system of humans. OBJECTIVE: to establish the correlation between clinical and tomographic variables in patients with neurocysticercosis in the neurology consultation of Hospital San Vicente de Paul and Hospital IESS Ibarra, during the year 2020. PATIENTS AND METHODS: descriptive, correlational and cross-sectional research. POPULATION AND SAMPLE: 93 patients. The information was collected in the neurology consultation. Clinical and imaging criteria were used for diagnosis. Odds Ratio (OR; 95% CI) was calculated. For multivariate analysis, binary logistic regression models were used. Statistical significance was considered when the value of p <0.05. SYMPTOMS: headache (77.4%), epilepsy (41.9%). Tomographic findings: size < 1 cm (67.7%), single lesion (54.8%), supratentorial (93.5%). There were several clinical / tomographic correlations in the bivariate analysis, the presence of epilepsy was associated with lesions of size >1 cm (OR: 9.65; 95% CI: 3.48-26.7), the vesicular + ventricular colloidal stage + nodular (OR: 3.90; 95% CI: 1.64-9.28) and parenchymal topography (OR: 5.03; 95% CI: 2.03-12.4) (p < 0.05). In the multivariate analysis, epilepsy was not associated with tomographic aspects such as the size, stage and topography of the cysticerci (p < 0.05). Headache and reduced muscle strength were associated with parenchymal topography and stage of lesions respectively (p < 0.05). CONCLUSIONS: Despite having a wide clinical spectrum, the presence of epilepsy, headache, and reduced muscle strength seem to be the most representative manifestations, so their inclusion in the development of prognostic scores should be evaluated, which allow evaluating the approach diagnostic and evolutionary in subsequent research.

TITLE: Correlación entre variables clínicas y tomográficas en pacientes con neurocisticercosis. Estudio en una cohorte de pacientes de la Sierra Norte ecuatoriana entre 2019 y 2020.Introducción. La neurocisticercosis es la enfermedad parasitaria más frecuente en el sistema nervioso central de los humanos. Objetivo. Establecer la correlación entre variables clínicas y tomográficas en pacientes con neurocisticercosis en la consulta de neurología del Hospital San Vicente de Paúl y el Hospital Instituto Ecuatoriano de Seguridad Social de Ibarra durante 2020. Pacientes y métodos. Investigación descriptiva, correlacional y transversal. Población y muestra: 93 pacientes. La información se recolectó en la consulta de neurología. Para el diagnóstico se utilizaron criterios clínicos e imagenológicos. Se calculó la odds ratio (OR) ­intervalo de confianza al 95% (IC 95%)­. Para el análisis multivariado, se utilizaron modelos de regresión logística binaria. Se consideró significación estadística cuando p menor de 0,05. Resultados. Síntomas: cefalea (77,4%) y crisis epilépticas (41,9%). Hallazgos tomográficos: tamaño menor de 1 cm (67,7%), lesión única (54,8%) y lesión supratentorial (93,5%). Hubo varias correlaciones clinicotomográficas en el análisis bivariado: la presencia de crisis epilépticas se asoció con lesiones de tamaño > 1 cm (OR: 9,65; IC 95%: 3,48-26,7), el estadio vesicular + ventricular coloidal + nodular (OR: 3,9; IC 95%: 1,64-9,28) y la topografía parenquimatosa (OR: 5,03; IC 95%: 2,03-12,4) (p menor de 0,05). La cefalea y la reducción de la fuerza muscular se asociaron con topografía parenquimatosa y estadio de las lesiones, respectivamente (p menor de 0,05). Conclusiones. A pesar de cursar con un amplio espectro clínico, la presencia de crisis epilépticas, cefalea y reducción de la fuerza muscular parece ser la manifestación más representativa, por lo que debería evaluarse su inclusión en el desarrollo de puntuaciones pronósticas que permitan evaluar el enfoque diagnóstico y evolutivo por estudio de imagen en investigaciones posteriores.

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Armchair graphene nanoribbons, when forming a superlattice, can be classified into different topological phases, with or without edge states. By means of tight-binding and classical molecular dynamics (MD) simulations, we studied the electronic and mechanical properties of some of these superlattices. MD shows that fracture in modulated superlattices is brittle, as for unmodulated ribbons, and occurs at the thinner regions, with staggered superlattices achieving a larger fracture strain than inline superlattices. We found a general mechanism to induce a topological transition with strain, related to the electronic properties of each segment of the superlattice, and by studying the sublattice polarization we were able to characterize the transition and the response of these states to the strain. For the cases studied in detail here, the topological transition occurred at ∼3-5% strain, well below the fracture strain. The topological states of the superlattice - if present - are robust to strain even close to fracture. The topological transition was characterized by means of the sublattice polarization of the states.

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Monocytes play a key role in pathophysiology of antiphospholipid syndrome (APS), nevertheless it is unclear if microRNA expression is associated with particular APS features. Identify whether miR-19b-3p and miR-20a-5p expression in monocytes are associated with hallmarks of the APS. Fifty-seven APS patients and 18 healthy controls were studied. Expression of miR-19b-3p and miR-20a-5p was measured in monocytes by RT-qPCR. Both miR-19b-3p (AUC = 0.835, 95% CI 0.733-0.938; P < 0.001) and miR-20a-5p (AUC = 0.857, 0.757-0.957; P < 0.001) discriminated APS patients from healthy individuals. A cut-off point of 1.98 for miR-19-3p and 2.18 for miR-20a-5p showed that APS patients with low microRNA expression had higher levels of IgM and IgG anticardiolipin antibodies than patients with high microRNA expression. In addition, APS patients with low microRNA expression had higher IgG anti-ß2 glycoprotein I antibody levels than their counterparts with high microRNA expression. Finally, miR-19b-3p and miR-20a-5p expression levels were significantly higher in APS patients using oral anticoagulants. Monocyte expression of miR-19b-3p and miR-20a-5p is low in APS, and patients with the lowest microRNA expression presented the highest levels of antiphospholipid antibodies.

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There are many simulation studies of mechanical properties of graphene nanoribbons (GNR), but there is a lack of agreement regarding elastic and plastic behavior. In this paper we aim to analyze mechanical properties of finite-size GNR, including elastic modulus and fracture, as a function of ribbon size. We present classical molecular dynamics simulations for three different empirical potentials which are often used for graphene simulations: AIREBO, REBO-scr and REAXFF. Ribbons with and without H-passivation at the borders are considered, and the effects of strain rate and different boundaries are also explored. We focus on zig-zag GNR, but also include some armchair GNR examples. Results are strongly dependent on the empirical potential employed. Elastic modulus under uniaxial tension can depend on ribbon size, unlike predictions from continuum-scale models and from some atomistic simulations, and fracture strain and progress vary significantly amongst the simulated potentials. Because of that, we have also carried out quasi-static ab-initio simulations for a selected size, and find that the fracture process is not sudden, instead the wave function changes from Blöch states to a strong interaction between localized waves, which decreases continuously with distance. All potentials show good agreement with DFT in the linear elastic regime, but only the REBO-scr potential shows reasonable agreement with DFT both in the nonlinear elastic and fracture regimes. This would allow more reliable simulations of GNRs and GNR-based nanostructures, to help interpreting experimental results and for future technological applications.

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RESUMEN Objetivo. Caracterizar genéticamente los ovinos criollos colombianos y sus relaciones con razas de origen europeo. Materiales y métodos. 261 muestras de sangre de las siguientes poblaciones, fueron colectadas: Criollos de Lana (CL), Mora Colombiana (MC), Criollo de Pelo (CP), mestizos (Mes), Hampshire (Hamp), Corriedale (Corr), Katahdin (Kath), Pelibuey (Pel), En 40 fincas de ocho departamentos (Córdoba, Magdalena, Cesar, Atlántico, Valle del Cauca, Nariño, Boyacá y Tolima) y 30 muestras de Merino Español (ME), Merino Precoz (MP), Merinofleischschaf (MF), Segureño (Seg) y Uda (UD) de Nigeria. Un total de 15 marcadores microsatélites fueron incluidos en este estudio. Resultados. En ovinos criollos, el número promedio de alelos encontrado fue 6.20±1.48 (CL), 7.27±1.39 (CP) y 3.60±1.55 (MC); hallándose también alta diversidad genética en ellos (heterocigosidades superiores al 75%), valores negativos en el FIS revelaron alto grado de introgresión; además el FST reveló estructura genética tanto en los grupos criollos (FST=0.02**), como en los departamentos muestreados (FST=0.039**). Según la distancia genética, los ovinos criollos colombianos presentan diferencias con los ovinos foráneos. Conclusiones. Los resultados obtenidos recomiendan proteger la ovinocultura criolla puesto que se encuentra amenazada por los constantes cruzamientos con razas foráneas, lo que conllevaría a pérdida de la identidad genética y de los rasgos de adaptación propios de los animales criollos.

ABSTRACT Ojective. genetical characterization the creole Colombian sheep and their relationships with breeds of European origins. Materials and methods. Blood samples of 261 sheeps from the following populations were collected: Criollos de Lana (CL), Mora Colombiana (MC), Criollo de Pelo (CP), criollos mestizos (Mes), Hampshire (Hamp), Corriedale (Corr), Katahdin (Kath), Pelibuey (Pel), in 40 farms of 8 departments (Córdoba, Magdalena, Cesar, Atlántico, Valle del Cauca, Nariño, Boyacá, Tolima) and 30 samples of Merino Spanish, Merino Precoz (MP), Merinofleischschaf (MF), Segureño (Seg) and Uda (UD) de Nigeria. A total of 15 microsatellites markers were included inthis study. Results. In creole sheep, the average number of alleles was found 6.20±1.48 (CL), 7.27±1.39 (CP) y 3.60±1.55 (MC); high genetic diversity found (high heterozygosities 75%), negative values in the FIS revealed high degree of introgression; furthermore the FST revealed genetic structure in both: Creole sheep (FST=0.02**) and departments (FST=0.039**).According to genetic distance, the creole Colombian sheep differs with outsider sheep. Conclusions. The results recommend protecting the Creole sheep production because it has been threatened by constant cross with foreign breeds, which would lead to the loss of genetic identity and adapting traits of creole sheep themselves.

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OBJECTIVE: To explore whether the IFNL3/4 rs12979860 genotype may influence serum levels or production of interferon-inducible protein-10 (IP-10) by peripheral blood mononuclear cells from patients with systemic lupus erythematosus (SLE). METHODS: Sixty-six patients with SLE and 22 healthy blood donors (controls) were included. The IFNL3/4 rs12979860 polymorphism was genotyped by real-time polymerase chain reaction. IP-10 levels in sera supernatants of IFNα stimulated peripheral blood mononuclear cells were measured by enzime-linked immunosorbent assay. RESULTS: Allelic frequencies were CC (29%), CT (52%) and TT (20%) in SLE, and CC (32%), CT (41%) and TT (27%) in healthy controls. Median serum IP-10 levels were higher in SLE patients than in controls (190.8 versus 118.1 pg/ml; p < 0.001), particularly in those with high disease activity (278.5 versus 177.2 pg/ml; p = 0.037). However, serum IP-10 levels were not influenced by IFNL3/4 genotypes. Higher IP-10 production by peripheral blood mononuclear cells was found in both SLE patients (median 519.3 versus 207.6 pg/ml; p = 0.012) and controls (median 454.0 versus 201.7 pg/ml; p = 0.034) carrying the IFNL3/4 C allele compared with carriers of the T allele. CONCLUSIONS: Although IFNL3/4 rs12979860 allele C does not appear to influence serum IP-10 levels in SLE, it plays an important role in the production of IP-10 by peripheral blood mononuclear cells after IFNα stimulation.

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Acute coronary syndrome (ACS) can be triggered by the presence of inflammatory factors which promote the activation of immune cells by costimulatory molecules such as CD40 and its ligand CD40L. Environmental and genetic factors are involved in the etiology of the ACS. The aim of this study was to explore the gene and protein expression associated with CD40 and CD40L genetic variants in ACS patients from the western Mexican population. A total of 620 individuals from western Mexico were recruited: 320 ACS patients and 300 individuals without a history of ischemic cardiopathy were evaluated. The genotype was determined using TaqMan SNP genotyping assays. CD40 and CD40L expressions at the mRNA level were quantified using TaqMan Gene Expression Assays. Soluble protein isoforms were measured by enzyme-linked immunosorbent assay. We did not find evidence of association between CD40 (rs1883832, rs4810485, and rs11086998) and CD40L (rs3092952 and rs3092920) genetic variants and susceptibility to ACS, although rs1883832 and rs4810485 were significantly associated with high sCD40 plasma levels. Plasma levels of sCD40L can be affected by gender and the clinical spectrum of acute coronary syndrome. Our results do not suggest a functional role of CD40 and CD40L genetic variants in ACS. However, they could reflect the inflammatory process and platelet activation in ACS patients, even when they are under pharmacological therapy. Due to the important roles of the CD40-CD40L system in the pathogenesis of ACS, longitudinal studies are required to determine if soluble levels of CD40 and CD40L could be clinically useful markers of a recurrent cardiovascular event after an ACS.

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Lettuce (Lactuca sativa L.) constitutes one the most important vegetable crops worldwide. Poultry litter is being applied as an economically suitable alternative to nitrogen fertilizers in lettuce cultivation. However, little is known about the effects of this practice over this fresh product safety that is usually consumed as a salad. The aim of this work was to determine the microbiological quality and the nitrate content in lettuce produced, under field conditions, using either raw or composted poultry litter, coming from the same original batch. Two experiments were conducted in the experimental field of Facultad de Ciencias Agrarias (UNL, Santa Fe, Argentina) to assess the effects of recently extracted poultry litter that consisted of broiler chicken manure plus rice husk, or composted for 12 mo. The application amounts were: 20 T ha-1 (T1); 40 T ha-1 (T2); and no application of manure (T). Increasing the applied quantities had also increased the health risk associated with lettuce consumption, due to higher nitrate levels and microbial contamination. However, these risks were reduced by composting the material. Even when lettuce contamination with faecal bacteria was mainly due to the use of poultry litter, the number and incidence of pathogens were reduced when properly composted manure was applied instead of raw one. Increasing the dose of poultry litter applied also increases the health risk in lettuce. Though, when the material is properly composted, its fertilizing capacity is maintained, giving proper yields with lower nitrate levels and microbial contamination by enterobacteria.

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We propose a generalization of the Su-Schrieffer-Heeger (SSH) model of the bipartite lattice, consisting of a periodic array of domain walls. The low-energy description is governed by the superposition of localized states at each domain wall, forming an effective mono-atomic chain at a larger scale. When the domain walls are dimerized, topologically protected edge states can appear, just like in the original SSH model. These new edge states are formed exclusively by soliton-like states and therefore, the new topological states are qualitatively different from the regular SSH edge states. They posses a much longer localization length and are more resistant to on-site disorder, in marked contrast to the standard SSH case.

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We studied the soft landing of Ni atoms on a previously damaged graphene sheet by means of molecular dynamics simulations. We found a monotonic decrease of the cluster frequency as a function of its size, but few big clusters comprise an appreciable fraction of the total number of Ni atoms. The aggregation of Ni atoms is also modeled by means of a simple phenomenological model. The results are in clear contrast with the case of hard or energetic landing of metal atoms, where there is a tendency to form mono-disperse metal clusters. This behavior is attributed to the high diffusion of unattached Ni atoms, together with vacancies acting as capture centers. The findings of this work show that a simple study of the energetics of the system is not enough in the soft landing regime, where it is unavoidable to also consider the growth process of metal clusters.

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BACKGROUND: Childhood obesity is a serious public health problem in Mexico. Adult gut microbiota composition has been linked to obesity, but few studies have addressed the role of gut microbiota in childhood obesity. OBJECTIVES: The aim of this study is to compare gut microbiota composition in obese and normal-weight children and to associate gut microbiota profiles with amino acid serum levels and obesity-related metabolic traits. METHODS: Microbial taxa relative abundance was determined by 16S rRNA sequencing in 67 normal-weight and 71 obese children aged 6-12 years. Serum amino acid levels were measured by mass spectrometry. Associations between microbiota composition, metabolic parameters and amino acid serum levels were tested. RESULTS: No significant differences in phyla abundances or Firmicutes/Bacteroidetes ratios were observed between normal-weight and obese children. However, Bacteroides eggerthii abundance was significantly higher in obese children and correlated positively with body fat percentage and negatively with insoluble fibre intake. Additionally, Bacteroides plebeius and unclassified Christensenellaceae abundances were significantly higher in normal-weight children. Abundance of both these species correlated negatively with phenylalanine serum levels, a metabolite also found to be associated with obesity in Mexican children. CONCLUSIONS: The study identified bacterial species associated with obesity, metabolic complications and amino acid serum levels in Mexican children.

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Alzheimer's disease (AD) is characterized by progressive memory loss and dementia. The strong correlation between cognitive decline and the loss of synapses supports the idea that synaptic damage is a relevant pathogenic mechanism underlying AD progression. It has been shown that amyloid beta oligomers (AßOs) induce synaptotoxicity ultimately leading to the reduction of dendritic spine density, which underlies cognitive damage. However, the signaling pathways connecting AßOs to synaptic dysfunction have not been completely elucidated. In this review, we have gathered evidence on AßOs receptors and the signaling pathways involved in synaptic damage. We make special emphasis on a new AßOs induced axis that involves the tyrosine kinase ephrin receptor A4 (EphA4) and c-Abl tyrosine kinase activation. EphA4 is a key player in homeostatic plasticity, mediating dendritic spine remodeling and retraction. AßOs aberrantly activate EphA4 leading to dendritic spine elimination. c-Abl is activated in AßOs exposed neurons and in AD patient's brain, and the inhibition of activated c-Abl ameliorates cognitive deficits in AD mouse model. The EphA4 receptor activates c-Abl intracellular signaling. Therefore EphA4 is an emerging AßOs receptor and the activation of the EphA4/c-Abl axis would explain the synaptic spine alterations found in AD.

Assuntos

Assuntos

RESUMO

Acute coronary syndrome (ACS) is considered one of the main causes of death worldwide. Contradictory findings concerning the impact of the angiotensin-converting enzyme (ACE) gene on cardiovascular diseases have been reported. Previous conclusions point out that the variability in results depends on ethnicity and genetic polymorphisms to determine the association of rs4340 polymorphisms of the ACE gene and ACE circulating levels in ACS. Genotyping of rs4340 polymorphisms was performed in a total of 600 individuals from Western Mexico divided into two groups: the ACS and the control group (CG). The polymorphisms were identified by polymerase chain reaction. Serum ACE concentration was determined by enzyme-linked immunosorbent assay. D/D carriers had higher ACE levels than I/I carriers (3.6 vs 2.8 ng/mL, P < 0.0021) in the CG. The D/D genotype of the rs4340 polymorphism is associated with higher ACE concentration levels; however, the polymorphism was not associated with ACS.

Assuntos

RESUMO

The black rat (Rattus rattus) is an invasive species and potential reservoir of significant pathogens of man, domestic animals and wildlife. During the 2012-2014 austral summers, 201 black rats were captured and examined on the uninhabited Guafo Island, in Northern Chilean Patagonia (43.593029°S, 74.713481°W). The mite Ornithonyssus bacoti caused lymphoplasmacytic and eosinophilic dermatitis in all infected rats (105/210, 52%), but no skin lesions were observed in rats infected with Nosopsyllus spp. and Plocopsylla spp. fleas. Eighty-eight rats (44%) had mild lymphoplasmacytic and eosinophilic enterocolitis and 61 of these rats were infected with the nematode Heterakis spumosa. In the liver, 63 animals (31%) had areas of necrosis with histiocytic and eosinophilic inflammation associated with multiple Calodium hepaticum eggs, and in 15 cases there was co-infection with several Taenia taeniaeformis strobilocerci. Mild interstitial lymphoplasmacytic sialadenitis with intranuclear inclusion bodies, suggesting cytomegalovirus infection, was observed in 28 rats (15%). In the lung, alveolar histiocytosis (69 rats, 34%) and perivascular lymphocytic infiltrates (46 rats, 23%) were the most common findings. There was mild to moderate lymphoplasmacytic interstitial nephritis in 52 rats (26%) and in 15% of these cases Leptospira spp. antigen was detected in the distal renal tubules. Some of the diseases of black rats on Guafo Island are likely to play a role in rat population dynamics. The endemic Guafo Island long-clawed mole mouse (Geoxus lafkenche), sea lions and fur seals may be at risk for infection by some of these rat pathogens.

Assuntos

RESUMO

Emerging evidence proposes a link between immune changes and pain, which is consistent with the inflammation theory and the increased incidence of neurodegenerative diseases. Flavonoids have long been used because of their anti-inflammatory potential activity and they are considered a promising alternative to alleviate neuropathic pain. The aim of this study was to investigate the antihyperalgesic effect of hesperidin and the presence of pro-inflammatory cytokines evaluated at peripheral and central levels in the chronic constriction injury as model of neuropathic pain in rats. Mechanical and thermal hyperalgesia were assessed in the aesthesiometer and plantar tests, respectively, as related to the presence of cytokines concentrations (TNF-α, IL-1ß and IL-6) in sciatic nerve and segments of the spinal cord after 15 days chronic constriction injury model in rats receiving vehicle or hesperidin. Antihyperalgesic response of hesperidin (100 mg/kg) was associated to the presence of cytokines mainly at several sections of the spinal cord suggesting not only peripheral but also its involvement in central sensitization in the experimental neuropathic pain.

Assuntos