The effect of magnetic activity saturation in chromospheric flux-flux relationships

We present a homogeneous study of chromospheric and coronal flux-flux relationships using a sample of 298 late-type dwarf active stars with spectral types F to M. The chromospheric lines were observed simultaneously in each star to avoid spread due to long term variability. Unlike other works, we subtract the basal chromospheric contribution in all the spectral lines studied. For the first time, we quantify the departure of dMe stars from the general relations. We show that dK and dKe stars also deviate from the general trend. Studying the flux-colour diagrams we demonstrate that the stars deviating from the general relations are those with saturated X-ray emission and that those stars also present saturation in the H$\alpha$ line. Using several age spectral indicators, we show that they are younger stars than those following the general relationships. The non-universality of flux-flux relationships found in this work should be taken into account when converting between fluxes in different chromospheric activity indicators.Comment: Accepted for publication in the Monthly Notices of the Royal Astronomical Societ

Mast Cell Changes the Phenotype of Microglia via Histamine and ATP

Background/Aims: Microglia are the dynamic motile phagocytes of the brain considered the first line of defense against threats or disturbances to the Central Nervous System (CNS). Microglia help orchestrate the immunological response by interacting with others immune cells. Mast cells (MCs) are effector cells of the innate immune system distributed in all organs and vascularized tissues, brain included. Several molecular mechanisms for potential interactions between MCs and microglia have been determined. However, the effect of MCs on regulated exocytosis and phagocytic clearance in microglia has not been explored. Methods: Cocktails of MCs mediators (MCM) obtained at 37°C and 53°C were used to induce microglia activation. Changes in intracellular calcium [Ca2+]i and ATP release were studied by calcium and quinacrine fluorescence imaging. Fluorescent latex beads were used to assay phagocytosis in microglia after MCM treatment and compared to that measured in the presence of histamine, ATP and lipopolysaccharide (LPS). Iba-1 expression and area were quantified by immunofluorescence and histamine levels evaluated by ELISA techniques. Results: Local application onto microglia of the MC mediator cocktail elicited Ca2+ transients and exocytotic release associated with quinacrine dye de-staining. Ca2+ signals were mimicked by histamine and blocked by the H1 receptor (H1R) antagonist, cetirizine. Hydrolysis of ATP by apyrase also affected Ca2+ transients to a lesser extent. Iba-1 fluorescence, cell area and phagocytosis were enhanced by histamine through H1R. However, ATP prevented iba-1 expression and microglial phagocytosis. MCM showed combined effects of histamine and ATP, increasing the number of internalized microbeads per cell and area without raising iba1 expression. Conclusion: Our results highlight the relevance of MC-derived histamine and ATP in the modulation of secretory and phagocytic activities that would explain the heterogeneity of microglial responses in different pathological contexts.Agencia Estatal de Investigación/ProyectoJunta de Andalucí

A spectroscopy study of nearby late-type stars, possible members of stellar kinematic groups

Nearby late-type stars are excellent targets for seeking young objects in stellar associations and moving groups. The origin of these structures is still misunderstood, and lists of moving group members often change with time and also from author to author. Most members of these groups have been identified by means of kinematic criteria, leading to an important contamination of previous lists by old field stars. We attempt to identify unambiguous moving group members among a sample of nearby-late type stars by studying their kinematics, lithium abundance, chromospheric activity, and other age-related properties. High-resolution echelle spectra ($R \sim 57000$) of a sample of nearby late-type stars are used to derive accurate radial velocities that are combined with the precise Hipparcos parallaxes and proper motions to compute galactic-spatial velocity components. Stars are classified as possible members of the classical moving groups according to their kinematics. The spectra are also used to study several age-related properties for young late-type stars, i.e., the equivalent width of the lithium Li~{\sc i} \space 6707.8 \space \AA \space line or the $R'_{\rm HK}$ index. Additional information like X-ray fluxes from the ROSAT All-Sky Survey or the presence of debris discs is also taken into account. The different age estimators are compared and the moving group membership of the kinematically selected candidates are discussed. From a total list of 405 nearby stars, 102 have been classified as moving group candidates according to their kinematics. i.e., only $\sim$ 25.2 \% of the sample. The number reduces when age estimates are considered, and only 26 moving group candidates (25.5\% of the 102 candidates) have ages in agreement with the star having the same age as an MG memberComment: 39 pages, 11 figures. Accepted for publication in Astronomy \& Astrophysic

Thymidylate synthase gene variants as predictors of clinical response and toxicity to fluoropyrimidine-based chemotherapy for colorectal cancer

Abstract Background: Fluoropyrimidines form the chemotherapy backbone of advanced and metastatic colorectal cancer (CRC). These drugs are frequently associated with toxicity events that result in dose adjustments and even suspension of the treatment. The thymidylate synthase (TYMS) gene is a potential marker of response and toxicity to fluoropyirimidines as this enzyme is the molecular target of these drugs. Our aim was to assess the association between variants of TYMS with response and toxicity to fluoropyrimidines in patients with CRC in independent retrospective and prospective studies. Methods: Variants namely rs45445694, rs183205964, rs2853542 and rs151264360 of TYMS were genotyped in 105 CRC patients and were evaluated to define their association with clinical response and toxicity to fluoropyrimidines. Additionally, the relationship between genotypes and tumor gene expression was analyzed by quantitative polymerase chain reaction. Results: The 2R/2R (rs45445694) was associated with clinical response (p = 0.05, odds ratio (OR) = 3.45) and severe toxicity (p = 0.0014, OR = 5.21, from pooled data). Expression analysis in tumor tissues suggested a correlation between the 2R/2R genotype and low TYMS expression. Conclusions: The allele 2R (rs45445694) predicts severe toxicity and objective response in advanced CRC patients. In addition, the alleles G(rs2853542) and 6bp-(rs151264360) are independent predictors of response failure to chemotherapy. This is the first study made on a Latin American population that points out TYMS gene variants have predictive values for response and toxicity in patients with CRC treated with fluoropyrimidine-based chemotherapy

Cognitive impairment induced by delta9-tetrahydrocannabinol occurs through heteromers between cannabinoid CB1 and serotonin 5-HT2A receptors

Delta-9-tetrahydrocannabinol (THC), the main psychoactive compound of marijuana, induces numerous undesirable effects, including memory impairments, anxiety, and dependence. Conversely, THC also has potentially therapeutic effects, including analgesia, muscle relaxation, and neuroprotection. However, the mechanisms that dissociate these responses are still not known. Using mice lacking the serotonin receptor 5-HT2A, we revealed that the analgesic and amnesic effects of THC are independent of each other: while amnesia induced by THC disappears in the mutant mice, THC can still promote analgesia in these animals. In subsequent molecular studies, we showed that in specific brain regions involved in memory formation, the receptors for THC and the 5-HT2A receptors work together by physically interacting with each other. Experimentally interfering with this interaction prevented the memory deficits induced by THC, but not its analgesic properties. Our results highlight a novel mechanism by which the beneficial analgesic properties of THC can be dissociated from its cognitive side effects

Rotation, activity, and lithium abundance in cool binary stars

We have used two robotic telescopes to obtain time-series high-resolution spectroscopy and V I and/or by photometry for a sample of 60 active stars. Orbital solutions are presented for 26 SB2 and 19 SB1 systems with unprecedented phase coverage and accuracy. The total of 6,609 R=55,000 echelle spectra are also used to systematically determine effective temperatures, gravities, metallicities, rotational velocities, lithium abundances and absolute H{\alpha}-core fluxes as a function of time. The photometry is used to infer unspotted brightness, V - I and/or b - y colors, spot-induced brightness amplitudes and precise rotation periods. Our data are complemented by literature data and are used to determine rotation-temperature-activity relations for active binary components. We also relate lithium abundance to rotation and surface temperature. We find that 74% of all known rapidly-rotating active binary stars are synchronized and in circular orbits but 26% are rotating asynchronously of which half have Prot > Porb and e > 0. Because rotational synchronization is predicted to occur before orbital circularization active binaries should undergo an extra spin-down besides tidal dissipation. We suspect this to be due to a magnetically channeled wind with its subsequent braking torque. We find a steep increase of rotation period with decreasing effective temperature for active stars. For inactive, single giants with Prot > 100 d, the relation is much weaker. Our data also indicate a period-activity relation for H{\alpha} of the form RH{\alpha} \propto P - 0.24 for binaries and RH{\alpha} \propto P -0.14 for singles. Lithium abundances in our sample increase with effective temperature. On average, binaries of comparable effective temperature appear to exhibit 0.25 dex less surface lithium than singles. We also find a trend of increased Li abundance with rotational period of form log n(Li) \propto - 0.6 log Prot

Attitudes and burden in relatives of patients with schizophrenia in a middle income country

BACKGROUND: Most studies of family attitudes and burden have been conducted in developed countries. Thus it is important to test the generalizability of this research in other contexts where social conditions and extended family involvement may be different. The aim of this study was to assess the relationship between the attitudes of caregivers and the burden they experience in such a context, namely Arica, a town located in the northernmost region of Chile, close to the border with Peru and Bolivia. METHODS: We assessed attitudes towards schizophrenia (including affective, cognitive and behavioural components) and burden (including subjective distress, rejection and competence) in 41 main caregivers of patients with schizophrenia, all of whom were users of Public Mental Health Services in Arica. RESULTS: Attitude measures differed significantly according to socio-demographic variables, with parents (mainly mothers) exhibiting a more negative attitude towards the environment than the rest of the family (t = 4.04; p = 0.000).This was also the case for caregivers with a low educational level (t = 3.27; p < 0.003), for the oldest caregivers (r = 0.546; p = 0.000) and for those who had spent more time with the patient (r = 0.377; p = 0.015). Although attitudes had significant association with burden, their explanatory power was modest (R2 = .104, F = 4,55; p = .039). CONCLUSIONS: Similar to finding developed countries, the current study revealed a positive and significant relationship between the attitudes of caregivers and their burden. These findings emphasize the need to support the families of patients with schizophrenia in this social context

Clinical and tear cytokine profiles after advanced surface ablation refractive surgery: A six-month follow-up

Producción CientíficaNeuropathic dry eye is one of the most frequently seen complications after corneal refractive surgery, however, its incidence decreases in a significant manner along the first six months postoperative, reaching between 10 and 45% incidence. However, little is known on the inflammatory status of the ocular surface during this recovery process. We aim to analyze the clinical and tear molecule concentration changes along six months after advanced surface ablation for myopia correction, in a prospective study including 18 eyes of 18 subjects who bilaterally underwent advanced surface ablation corneal refractive surgery. Clinical variables (uncorrected distance visual acuity, symptoms, conjunctival hyperemia, tear osmolarity, tear stability, corneal fluorescein staining, conjunctival lissamine staining, Schirmer test, and corneal esthesiometry) and a panel of 23 pro and anti-inflammatory cytokines/chemokines concentration in tears preoperatively and at 1, 3 and 6 months postoperatively were evaluated. We found that uncorrected distance visual acuity improved significantly from baseline at 1-month visit, symptoms improved and tear osmolarity decreased significantly from baseline at 3-month visit and there was a decrease in mechanical corneal threshold between 1-month and 3- and 6-month visits. Regarding tear molecules, IL-4, IL-5, IL-6, IL-13, IL-17A, and IFN-γ tear levels were significantly increased at all the three visits, compared to preoperative levels at V0; IL-2 and VEGF were also significantly increased at 1-month and 6-month visits, but not at 3-month visit, whereas IL-9 IL-10 and IL-12 were only significantly increased at 6-month visit. Although we found that there is a recovery in clinical variables at 6 months postoperatively (i.e. neuropathic dry eye was not developed in the sample), ocular surface homeostasis is not completely restored, as it can be seen by the changes in concentration of some pro and anti-inflammatory molecules measured in tears.Partially supported by national grant (AES) from the Ministry of 465 Economy and Competitiveness, Madrid, Spain, SAF2016-77080 AEI/FEDER, U

The Generalife and the arabian ruins of its surroundings: an unknown chapter of the "Nuevos paseos" by Simón de Argote

Los Nuevos paseos (1806-1807) de Simón de Argote constituyen una de las obras más notables escritas sobre la Alhambra y suponen una respuesta ilustrada a las tergiversaciones sobre el pasado romano de Granada del clérigo y arabista Velázquez de Echeverría. Desgraciadamente la obra quedó incompleta porque no llegó a cumplir su objetivo de abarcar las “antigüedades árabes” ubicadas fuera de la ciudadela nazarí. En este artículo se presenta, con anotaciones críticas, un capítulo inédito dedicado al Generalife y a las ruinas de su entorno, el cual fue entregado por su autor al rey José Bonaparte durante su estancia en Granada y se conservó entre los papeles perdidos por el monarca en la batalla de Vitoria. A partir de documentación hallada en muy diversos archivos y publicaciones de la época se arroja luz sobre la mal conocida trayectoria de Simón de Argote y se profundiza en su relación con el general Horace Sebastiani, militar que por orden de Napoleón realizó labores de embajador en Estambul y en otras ciudades de Próximo Oriente, antes de gobernar el Reino de Granada.Simón de Argote’s Nuevos paseos (1806- 1807) is one of the most remarkable works written on the Alhambra. It offers an Enlightenment response to the distortions of the Roman past of Granada of the cleric and Arabist Velázquez de Echeverría. Unfortunately, the work was unfinished because it did not cover all the «Arabian antiques» located outside the Nasrid city. In this article, an unknown chapter about the Generalife and the ruins around is presented, accompanied with critical notes. It was given by the author to King Joseph Bonaparte during his stay in Granada and it was kept among the papers the king had lost at the Battle of Vitoria. The study of the documents found in different archives and publications of that time sheds some light on the mysterious personality of Simón de Argote and deepens in the knowledge of his relationship with General Horace Sebastiani, a military who was embassador in Istanbul and other cities of the Middle East under Napoleon’s order, before he ruled the Kingdom of Granada

Charge separation relative to the reaction plane in Pb-Pb collisions at sNN=2.76\sqrt{s_{\rm NN}}= 2.76 TeV

Measurements of charge dependent azimuthal correlations with the ALICE detector at the LHC are reported for Pb-Pb collisions at $\sqrt{s_{\rm NN}} = 2.76$ TeV. Two- and three-particle charge-dependent azimuthal correlations in the pseudo-rapidity range $|\eta| < 0.8$ are presented as a function of the collision centrality, particle separation in pseudo-rapidity, and transverse momentum. A clear signal compatible with a charge-dependent separation relative to the reaction plane is observed, which shows little or no collision energy dependence when compared to measurements at RHIC energies. This provides a new insight for understanding the nature of the charge dependent azimuthal correlations observed at RHIC and LHC energies.Comment: 12 pages, 3 captioned figures, authors from page 2 to 6, published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/286