Enfermedad de Alzheimer y degeneración macular asociada a la edad

[Resumen] Objetivos: Analizar diferentes factores de riesgo implicados en la aparición de la enfermedad de Alzheimer y de la degeneración macular asociada a la edad, tratando de establecer una relación de asociación entre ambas entidades. Métodos: Sobre una muestra de 57 sujetos, de los que 33 presentan demencia (casos) y 24 no (controles) se realiza estudio analítico a fin de establecer el grado de asociación entre la enfermedad de Alzheimer (EA) y la degeneración macular asociada a la edad (DMAE). Para ello, tras realizar anamnesis a todos los sujetos, se estudia el fondo de ojo mediante cámara no midriática tipo Topcon TRV-50VT. Resultados: De acuerdo a la hipótesis de trabajo planteada, aplicada la razón de productos cruzados o de disparidad (odds ratio) se obtuvo un resultado positivo que determina relación causa efecto, ya que el porcentaje de casos con DMAE (42,4%) es superior al de controles con DMAE (25%). Por otro lado mediante la Chi cuadrado de Pearson, aunque no se establecieron diferencias significativas, los datos obtenidos muestran protección en el grupo control de acuerdo al estadístico exacto de Fisher (p=0,649). Conclusiones: Existen evidencias suficientes para pensar que la EA y la DMAE podrían tener factores etiológicos y patogénicos comunes, y aunque en nuestro estudio no hemos podido establecer la relación significativa entre ambas patologías, posiblemente en base al tamaño de la muestra o a las diferencias de edades entre ambos grupos, creemos establecida la posible asociación como para plantear un futuro trabajo que pueda confirmar estos hallazgos.[Abstract] Objectives: We analysed different risk factors involved in the onset of both Alzheimer’s disease (AD) and age-related macular degeneration (ARMD). The putative relation between both disorders was studied. Methods: We studied 57 subjects to determine the correlation between AD and ARMD. Thirty-three of the subjects suffered dementia (cases), whereas 24 of them (controls) did not. Firstly, anamnesis was performed for all individuals. We then examined the macular area of the eye using a non-midriatic TRV-50VT fundus camera. Significant odds ratio (OR) results were used as a statistical tool to survey the putative link between AD and ARMD. Results: The OR test results showed that ARMD was associated with Alzheimer’s disease. The occurrence of ARMD was significantly higher for cases (42.4%) than for controls (25%). On this basis, we inferred a cause-effect relation linking both variables. Our dataset suggested that the control group was more protected against ARMD than the case group, as revealed by Fisher’s exact test (P = 0.649). However, such a difference between both groups was not strongly supported. Conclusions: We suggest that AD and ARMD may have common factors concerning etiology and pathogenesis. Our dataset did not allow us to show a significant relation between both disorders, which is likely due to sample size and/or to age differences in the two studied groups. Even so, we feel that the possibility of such an association is justified, and future surveys to test this possibility are warranted

Simulación de un lavado hidráulico en tuberías para el control del crecimiento de biopelicula

Este artículo presenta un problema actual y de gran importancia en los sistemas de acueducto, el cual es la biopelícula que se desarrolla al interior de las paredes de las tuberías y que puede presentar problemas en la calidad del agua y predisposición de los usuarios respecto al servicio público que se presta. Se presenta una revisión de los mecanismos físicos que la generan y el control de la biopelícula en tuberías mediante el Lavado Hidráulico. En este caso se hace una simulación hidráulica aplicada a una red que permite conocer si se tienen zonas propensas a la formación de la biopelícula, considerando parámetros de velocidad de flujo y tiempo de permanencia de la zona en condiciones críticas. Se puede estimar si las presiones y velocidades obtenidas están en el rango aceptado por el ente regulador del servicio. Además, se pueden definir criterios de simulación y operación en una red para el control de la biopelícula

Observaciones y comentarios biogeográficos sobre la avifauna del este de la provincia de San Juan, Argentina

New records and biogeographic comments on the avifauna of eastern San Juan Province (Argentina Republic). New data on the subtropical avifauna of the E region of San Juan Province are given. 18 of 35 species mentioned in this paper lack well documented previous records, and tbe information on the remaining 17 is scarce. Comparison of these results with available biogeographic literature allow us to confirm penetration in San Juan of a subtropical ornitogeographic flow, which follows xerophytic wood relics of Mountain and Western Chaco districts. This penetration occurs within a wide transition with Monte scrublands

Influence of the organic linker substituent on the catalytic activity of MIL-101(Cr) for the oxidative coupling of benzylamines to imines

[EN] MIL-101(Cr) having substituents at the terephthalate linker (X = H, NO2, SO3H, Cl, CH3 and NH2) promotes the aerobic oxidation of benzylamines to the corresponding N-benzylidene benzylamines at different rates. MIL-101(Cr)¿NO2 was the most active catalyst, about 6-fold more active than the parent MIL-101(Cr). MIL-101(Cr)¿NO2 does not deactivate significantly upon five consecutive reuses, does not leach the metal to the solution and maintains its crystallinity. MIL-101(Cr)¿NO2 is active for a wide range of benzylamines including para-substituted, heterocyclic benzylamines and di- and tribenzylamines.Financial support by the Spanish Ministry of Economy and Competitiveness (CTQ 2015-69153-CO2-1, CTQ2014-53292-R, Severo Ochoa) and Generalitat Valenciana (Prometeo 2013014) is gratefully acknowledged.Santiago-Portillo, A.; Blandez, JF.; Navalón Oltra, S.; Alvaro Rodríguez, MM.; García Gómez, H. (2017). Influence of the organic linker substituent on the catalytic activity of MIL-101(Cr) for the oxidative coupling of benzylamines to imines. Catalysis Science & Technology. 7(6):1351-1362. https://doi.org/10.1039/c6cy02577cS135113627

Deep XMM-Newton observation of the Eta Chamaleontis cluster

The members of the Eta Chamaleontis cluster are in an evolutionary stage in which disks are rapidly evolving. It also presents some peculiarities, such as the large fraction of binaries and accretion disks, probably related with the cluster formation process. Its proximity makes this stellar group an ideal target for studying the relation between X-ray emission and those stellar parameters. The main objective of this work is to determine general X-ray properties of the cluster members in terms of coronal temperature, column density, emission measure, X-ray luminosity and variability. We also aim to establish the relation between the X-ray luminosity of these stars and other stellar parameters, such as binarity and presence of accretion disks. A study of flare energies for each flare event and their relation with some stellar parameters is also performed. We used proprietary data from a deep XMM-Newton observation pointed at the core of the Eta Chamaleontis cluster. Specific software for the reduction of XMM-Newton data was used for the analysis of our observation. For the detection of sources, we used the wavelet-based code PWDetect. General coronal properties were derived from plasma model fitting. We also determined variability of the Eta Chamaleontis members in the EPIC field-of-view. A total of six flare-like events were clearly detected in five different stars. For them, we derived coronal properties during the flare events and pseudo-quiescent state separately. In our observations, stars that underwent a flare event have higher X-ray luminosities in the pseudo-quiescent state than cluster members with similar spectral type with no indications of flaring, independently whether they have an accretion disk or not. Observed flare energies are typical of both pre-main and main-sequence M stars. We detected no difference between flare energies of stars with and without an accretion disk.Comment: Accepted for publication in Astronomy and Astrophysics. 12 pages, 30 individual figure

Prevalence of daily family meals among children and adolescents from 43 countries

Prevalence studies about family meals, including large and representative samples of children and adolescents on this topic, are scarce. Therefore, the aim of this study was twofold: first, to determine the prevalence of daily family meals in large and representative samples of school‐going children and adolescents from 43 countries, and second, to identify the sex, age, socioeconomic status (SES), family structure, immigrant status and parental labour market status inequalities associated with this prevalence. Using data from the 2017/2018 wave of the Health Behaviour in School‐aged Children study, a total of 179,991 participants from 43 countries were involved in this cross‐sectional study. Family meals were assessed by the following question: ‘How often do you and your family usually have meals together?’. Participants had five different response options: ‘every day’, ‘most days’, ‘about once a week’, ‘less often’, and ‘never’. The meta package was utilized for conducting a meta‐analysis of single proportions, specifically applying the metaprop function. The analysis involved pooling the data using a random‐effects model and presenting the outcomes through a forest plot generated using the inverse variance method. Moreover, we applied generalized linear mixed models to explore the relationships between the studied sociodemographic factors as fixed effects, country as a random effect and the status of daily family meals as an outcome. Overall, the prevalence of daily family meals was 49.12% (95% confidence interval [CI]: 45.00–53.25). A greater probability of having daily family meals was identified for children aged 10–12 years (61.55%; 95% CI: 57.44%–65.49%), boys (61.55%, 95% CI: 57.44%–65.49%), participants with high SES (64.66%, 95% CI: 60.65%–68.48%), participants with both parents at home (65.05%, 95% CI: 61.16%–68.74%) and those with both unemployed parents (61.55%, 95% CI: 57.44%–65.49%). In the present study, which included large representative samples of school‐going children and adolescents from 43 countries, more than half of the participants did not have daily family meals

Effect of an organotin catalyst on the physicochemical properties and biocompatibility of castor oil-based polyurethane/cellulose composites

[EN] Polyurethane/cellulose composites were synthesized from castor-oil-derived polyols and isophorone diisocyanate using dibutyltin dilaurate (DBTDL) as the catalyst. Materials were obtained by adding 2% cellulose in the form of either microcrystals (20 lm) or nanocrystals obtained by acid hydrolysis. The aim was to assess the effects of filler particle size and the use of a catalyst on the physicochemical properties and biological response of these composites. The addition of the catalyst was found to be essential to prevent filler aggregations and to enhance the tensile strength and elongation at break. The cellulose particle size influenced the composite properties, as its nanocrystals heighten hydrogen bond interactions between the filler surface and polyurethane domains, improving resistance to hydrolytic degradation. All hybrids retained cell viability, and the addition of DBTDL did not impair their biocompatibility. The samples were prone to calcification, which suggests that they could find application in the development of bioactive materials.Universidad de La Sabana supported this work under Grant No. ING-176-2016. S.V.V. acknowledges the Universidad de La Sabana for the Teaching Assistant Scholarship for his master's studies. J.A.G.T. and A.V.L. acknowledge the support of the Spanish Ministry of Economy and Competitiveness (MINECO) through project DPI2015-65401-C3-2-R (including FEDER financial support). The authors acknowledge the assistance and advice of the Electron Microscopy Service of the UPV. CIBER-BBN is an initiative funded by the VI National R&D&I Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program. CIBER Actions are financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund.Villegas-Villalobos, S.; Diaz, L.; Vilariño, G.; Vallés Lluch, A.; Gómez-Tejedor, J.; Valero, M. (2018). 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Genetic variants in the PPARD-PPARGC1A-NRF-TFAM mitochondriogenesis pathway are neither associated with muscle characteristics nor physical performance in elderly

We studied the influence of genetic polymorphisms involved in the PPARD-PPARGC1A-NRF-TFAM mitochondriogenesis pathway (rs6949152, rs12594956, rs2267668, rs8192678, and rs1937) on muscle phenotypes (thigh muscles’ cross-sectional, maximal handgrip-strength and 30-second chair stand-test) and Barthel index in Caucasian (Spanish) community-dwelling old people (n=75, 21 men, 54 women; 71–94 years). We found no significant genetic associations with the studied phenotypes. Multiple, com- plex gene-environment and gene-gene interactions which are yet to be determined are likely to play a more determinant role