Testing the relevance of effective interaction potentials between highly charged colloids in suspension

Combining cell and Jellium model mean-field approaches, Monte Carlo together with integral equation techniques, and finally more demanding many-colloid mean-field computations, we investigate the thermodynamic behavior, pressure and compressibility of highly charged colloidal dispersions, and at a more microscopic level, the force distribution acting on the colloids. The Kirkwood-Buff identity provides a useful probe to challenge the self-consistency of an approximate effective screened Coulomb (Yukawa) potential between colloids. Two effective parameter models are put to the test: cell against renormalized Jellium models

Chocolate, Air Pollution and Children's Neuroprotection: What Cognition Tools should be at Hand to Evaluate Interventions?

Indexación: Web of ScienceMillions of children across the world are exposed to multiple sources of indoor and outdoor air pollutants, including high concentrations of fine particulate matter (PM2.5) and ozone (O-3). The established link between exposure to PM2.5, brain structural, volumetric and metabolic changes, severe cognitive deficits (1.5-2 SD from average IQ) in APOE 4 heterozygous females with >75 - <94% BMI percentiles, and the presence of Alzheimer's disease (AD) hallmarks in urban children and young adults necessitates exploration of ways to protect these individuals from the deleterious neural effects of pollution exposure. Emerging research suggests that cocoa interventions may be a viable option for neuroprotection, with evidence suggesting that early cocoa interventions could limit the risk of cognitive and developmental concerns including: endothelial dysfunction, cerebral hypoperfusion, neuroinflammation, and metabolic detrimental brain effects. Currently, however, it is not clear how early we should implement consumption of cocoa to optimize its neuroprotective effects. Moreover, we have yet to identify suitable instruments for evaluating cognitive responses to these interventions in clinically healthy children, teens, and young adults. An approach to guide the selection of cognitive tools should take into account neuropsychological markers of cognitive declines in patients with Alzheimer's neuropathology, the distinct patterns of memory impairment between early and late onset AD, and the key literature associating white matter integrity and poor memory binding performance in cases of asymptomatic familial AD. We highlight potential systemic and neural benefits of cocoa consumption. We also highlight Working Memory Capacity (WMC) and attention control tasks as opened avenues for exploration in the air pollution scenario. Exposures to air pollutants during brain development have serious brain consequences in the short and long term and reliable cognition tools should be at hand to evaluate interventions.http://journal.frontiersin.org/article/10.3389/fphar.2016.00232/ful

Insuficiente adherencia al ejercicio físico de universitarios. Una revisión sistemática

A sedentary lifestyle is one of the main problems for the health of the world population of the 21st century. Due to the sociocultural characteristics presented by university students, it is a suitable population for the study and promotion of physical activity (PA). The main aim of the present systematic review is to give a general view on the adherence to the practice of PA among the university population, as well as intervention programs aimed at promoting this practice, from 2007 to the present day. The methodology used has been guided by the PRISMA statement. As main conclusion, 100% of the studies of the first selection support the urgent need for the creation and implementation of intervention programs aimed at promoting the practice of PA among university students. Finally, the intervention programs studied obtained good results, achieving in most of them an increase in the adherence to the practice of PA of the population studied.El sedentarismo se constituye como uno de los principales problemas para la salud de la población mundial del siglo XXI. Debido a las características socioculturales que presentan los estudiantes universitarios, resulta una población idónea para el estudio y fomento de actividad física (AF). El objetivo principal de la presente revisión sistemática es dar una visión general sobre la adherencia a la práctica de AF entre la población universitaria, así como de los programas de intervención dirigidos a fomentar dicha práctica, desde el año 2007 hasta nuestros días. La metodología utilizada ha estado dirigida por la declaración PRISMA. Como principales conclusiones, el 100% de los estudios de la primera selección sostienen la urgente necesidad de la creación e implementación de programas de intervención dirigidos a fomentar la práctica de AF entre estudiantes universitarios. Finalmente, la mayoría de los programas de intervención estudiados consiguen incrementar la adherencia a la práctica de AF

Antinocicepción opioide del extracto metanólico del Chuchuhuasi (Maytenus krukovii) en un modelo de dolor visceral en ratón

Evaluamos la acción antinociceptiva del extracto metanólico del Chuchuhuasi (Maytenus krukovii), al 20%, administrado por vía oral, en ratones albinos, machos, raza Webster Suizo obtenidos del Centro Nacional de Producción de Biológicos del Ministerio de Salud del Perú, utilizando un modelo de dolor visceral, mediante la administración de ácido acético al 2%, vía intraperitoneal, a la dosis de 0,05 ml/10g de peso. Observamos una disminución del 50% del número de contorsiones abdominales, en relación al grupo control, sin prolongación del período de latencia de las mismas. El efecto analgésico observado, fue bloqueado por la naloxona, lo que sugeriría la participación de receptores opioides, o de opioides endógenos en el mecanismo de la acción analgésica. Los resultados fueron analizados estadísticamente mediante el programa estadístico SPSS versión 11.5

Small-spatial scale variations of nebular properties and the abundance discrepancy in three Galactic HII regions

We present results of long-slit spectroscopy in several slit positions that cover different morphological structures of the central parts of three bright Galactic HII regions: M8, M17 and NGC7635. We study the spatial distributions of a large number of nebular parameters such as the extinction coefficient, line fluxes, physical conditions and ionic abundances at the maximum spatial resolution attainable with our instrumentation. Particularly, our goal is to study the behaviour of the abundance discrepancy factor of O^{2+}, ADF(O^{2+}), defined as the logarithmic difference of the O^{2+} abundances derived from collisionally excited and recombination lines. We find that the ADF(O^{2+}) remains fairly constant along the slit positions of M8 and M17. In the case of NGC7635, we only detect the OII recombination lines in the integrated spectrum along the whole slit, where the ADF(O^{2+}) reaches a remarkably high value of about 0.59 dex. We compare our results with previous ones obtained for the Orion Nebula. We find several evidences that suggest the presence of a candidate to Herbig-Haro object in M8.Comment: 18 pages, 9 figures. Table A1 available only in the online version. Accepted for publication in MNRAS

Spatially resolved study of the physical properties of the ionized gas in NGC 595

We present Integral Field Spectroscopy (IFS) of NGC 595, one of the most luminous HII regions in M33. This type of observations allows studying the variation of the principal emission-line ratios across the surface of the nebula. At each position of the field of view, we fit the main emission-line features of the spectrum within the spectral range 3650-6990A, and create maps of the principal emission-line ratios for the total surface of the region. The extinction map derived from the Balmer decrement and the absorbed H-alpha luminosity show good spatial correlation with the 24 micron emission from Spitzer. We also show here the capability of the IFS to study the existence of Wolf-Rayet (WR) stars, identifying the previously catalogued WR stars and detecting a new candidate towards the north of the region. The ionization structure of the region nicely follows the H-alpha shell morphology and is clearly related to the location of the central ionizing stars. The electron density distribution does not show strong variations within the HII region nor any trend with the H-alpha emission distribution. We study the behaviour within the HII region of several classical emission-line ratios proposed as metallicity calibrators: while [NII]/Ha and [NII]/[OIII] show important variations, the R23 index is substantially constant across the surface of the nebula, despite the strong variation of the ionization parameter as a function of the radial distance from the ionizing stars. These results show the reliability in using the R23 index to characterize the metallicity of HII regions even when only a fraction of the total area is covered by the observations.Comment: 16 pages, 12 figures, published in MNRAS (replaced to match the journal version). Based on observations collected at the German-Spanish Astronomical Center, Calar Alto, (MPIA and IAA-CSIC

Reduced IgG anti-small nuclear ribonucleoprotein autoantibody production in systemic lupus erythematosus patients with positive IgM anti-cytomegalovirus antibodies

INTRODUCTION: Systemic lupus erythematosus is characterized by production of autoantibodies to RNA or DNA-protein complexes such as small nuclear ribonucleoproteins (snRNPs). A role of Epstein-Barr virus in the pathogenesis has been suggested. Similar to Epstein-Barr virus, cytomegalovirus (CMV) infects the majority of individuals at a young age and establishes latency with a potential for reactivation. Homology of CMV glycoprotein B (UL55) with the U1snRNP-70 kDa protein (U1-70 k) has been described; however, the role of CMV infection in production of anti-snRNPs is controversial. We investigated the association of CMV serology and autoantibodies in systemic lupus erythematosus. METHODS: Sixty-one Mexican patients with systemic lupus erythematosus were tested for CMV and Epstein-Barr virus serology (viral capsid antigen, IgG, IgM) and autoantibodies by immunoprecipitation and ELISA (IgG and IgM class, U1RNP/Sm, U1-70 k, P peptide, rheumatoid factor, dsDNA, beta2-glycoprotein I). RESULTS: IgG anti-CMV and IgM anti-CMV were positive in 95% (58/61) and 33% (20/61), respectively, and two cases were negative for both. Clinical manifestation and autoantibodies in the IgM anti-CMV+ group (n = 20) versus the IgM anti-CMV(-)IgG+ (n = 39) group were compared. Most (19/20) of the IgM anti-CMV+ cases were IgG anti-CMV+, consistent with reactivation or reinfection. IgM anti-CMV was unrelated to rheumatoid factor or IgM class autoantibodies and none was positive for IgM anti-Epstein-Barr virus-viral capsid antigen, indicating that this is not simply due to false positive results caused by rheumatoid factor or nonspecific binding by certain IgM. The IgM anti-CMV+ group has significantly lower levels of IgG anti-U1RNP/Sm and IgG anti-U1-70 k (P = 0.0004 and P = 0.0046, respectively). This finding was also confirmed by immunoprecipitation. Among the IgM anti-CMV(-) subset, anti-Su was associated with anti-U1RNP and anti-Ro (P < 0.05). High levels of IgG anti-CMV were associated with production of lupus-related autoantibodies to RNA or DNA-protein complex (P = 0.0077). CONCLUSIONS : Our findings suggest a potential role of CMV in regulation of autoantibodies to snRNPs and may provide a unique insight to understand the pathogenesis

Evaluación citológica y microbiológica de lavados uterinos en bovinos con problemas reproductivos (estudio preliminar)

RESUMEN Objetivo. Determinar las características citológicas y microbiológicas de lavados uterinosde bajo volúmen en hembras con problemas reproductivos en dos hatos del AltiplanoCundiboyacense. Materiales y métodos. Se evaluaron 21 muestras de lavados uterinosde vacas con historia de problemas reproductivos procedentes de dos hatos lecheros, enel primer hato ubicado en Sibaté (Cundinamarca) se muestrearon 10 animales y en elsegundo ubicado en Ventaquemada (Boyacá) se obtuvieron las 11 muestras restantes. Serealizó evaluación macroscópica y microscópica de cada uno de los lavados uterinos; parala evaluación citológica se utilizaron las tinciones de Gram y Wright. La determinación de laflora bacteriana se realizó mediante técnicas estándar en microbiología para la identificaciónde bacterias no exigentes, adicionalmente se realizaron pruebas de sensibilidad por latécnica de difusión de Kirby-bauer. Resultados. En la citología se observaron bacilosy cocos gram positivos, células epiteliales de descamación uterina (CEDU) y respuestainflamatoria (RI) mediada por polimorfonucleares (PMN). Los aislamientos bacterianoscorrespondieron a Lactobacillus sp como flora bacteriana normal del tracto genital (16.66%)y Klebsiella sp como flora acompañante (16.66%); adicionalmente se aislaron bacteriaspatógenas causantes de problemas reproductivos como Streptococcus sp. β hemolítico(33.33%), Streptococcus sp α hemolítico (50%) y Streptococcus sp. γ hemolítico (50%)y Arcanobacterium pyogenes (Corynebacterium-Actinomyces pyogenes) (16.66%); en un9.52% de las muestras se observaron espiroquetas. Conclusiones. Se observó una relacióndirecta entre el aspecto macroscópico de los lavados uterinos, la respuesta citológica y elaislamiento de bacterias

Molecular, morphological and acoustic identification of Eumops maurus and Eumops hansae (Chiroptera: Molossidae) with new reports from Central Amazonia

Eumops maurus and Eumops hansae are rarely captured Neotropical molossid bats for which information on taxonomy, natural history, and spatial distribution are scarce. This translates into a poor understanding of their ecology and limits the delimitation of useful characters for their identification. Here, we describe records of these two molossids from the Central Brazilian Amazon, providing data on their external and craniodental morphology, DNA barcode (COI) sequences complemented by acoustic data for the species. Morphological characters, DNA sequence data and phylogenetic relationships within the genus Eumops were consistent with those previously described for both species. Echolocation call characteristics did not differ significantly so as to be useful for separating E. maurus and E. hansae from other congeners. Our records are, respectively the first and the second for Central Amazonia as one individual previously attributed to Eumops amazonicus from Manaus may be considered a junior synonym for E. hansae. These new records increase the extent of the species’ known ranges, partially filling in previous existing gaps in their distribution in central South America. Our data further suggest that these molossid bats forage in a wider range of habitats than previously thought

Basal ganglia volume predicts speed processing performance in obese adolescents

La obesidad se ha relacionado con cambios estructurales en los ganglios basales y alteraciones en dominios transversales como la velocidad de procesamiento. El objetivo del presente estudio es investigar la relación entre velocidad de procesamiento y volumen de los ganglios basales en adolescentes con y sin obesidad. Treinta y tres participantes obesos y treinta y tres con peso normal fueron resonados (Siemens 3T Trio) y evaluados neuropsicológicamente. Se compararon los resultados de un índice de velocidad y la ratio de los ganglios basales controlando por edad, sexo y tamaño de la cabeza. Se realizaron regresiones lineales con las estructuras relacionadas con este índice. Se encontraron diferencias en el índice de velocidad, pero no en la ratio de los ganglios basales. El grupo con obesidad mostró una correlación positiva entre velocidad y ratio del globo pálido derecho (r= .41; p= .021). No hallamos relaciones significativas en el grupo normopeso. La ratio del globo pálido derecho predijo parte del rendimiento en velocidad en adolescentes obesos. Las diferencias en velocidad de procesamiento entre adolescentes con y sin obesidad podrían estar moderadas por el tamaño de estructuras subcorticales como el globo pálido.Obesity is related to structural changes in basal ganglia and alterations among transversal domains such as speed processing. The aim of the study is to address the relationship between speed processing and basal ganglia volumes in adolescents with and without obesity. Thirty-three obese and 33 normal-weight participants underwent MRI acquisition (Siemens 3T Trio) and neuropsychological assessment to obtain an index of speed processing. Speed processing index and basal ganglia ratios (VolBrain software) were compared controlling for age, sex and head size. Linear regressions were conducted in the structures related to such index. Groups differed for speed processing index, but did not differ for basal ganglia ratios. The obese group showed positive correlations between speed processing index and the right globus pallidum ratio (r= .41; p= .021). None relationship was found among normal-weight adolescents. Concretely, the right globus pallidum ratio predicted part of the performance in speed in obese participants. The differences in speed processing between adolescents with and without obesity might be mediated by the size of subcortical structures such as the globus pallidum