Fluorine variations in the globular cluster NGC 6656 (M22): implications for internal enrichment timescales

Observed chemical (anti)correlations in proton-capture elements among globular cluster stars are presently recognized as the signature of self-enrichment from now extinct, previous generations of stars. This defines the multiple population scenario. Since fluorine is also affected by proton captures, determining its abundance in globular clusters provides new and complementary clues regarding the nature of these previous generations, and supplies strong observational constraints to the chemical enrichment timescales. In this paper we present our results on near-infrared CRIRES spectroscopic observations of six cool giant stars in NGC 6656 (M22): the main objective is to derive the F content and its internal variation in this peculiar cluster, which exhibits significant changes in both light and heavy element abundances. We detected F variations across our sample beyond the measurement uncertainties and found that the F abundances are positively correlated with O and anticorrelated with Na, as expected according to the multiple population framework. Furthermore, our observations reveal an increase in the F content between the two different sub-groups, s-process rich and s-process poor, hosted within M22. The comparison with theoretical models suggests that asymptotic giant stars with masses between 4 and 5 Msun are responsible for the observed chemical pattern, confirming evidence from previous works: the difference in age between the two sub-components in M22 must be not larger than a few hundreds Myr.Comment: Accepted for publication in The Astrophysical Journal, 10 pages, 10 figure

The cholesterol 24-hydroxylase activates autophagy and decreases mutant huntingtin build-up in a neuroblastoma culture model of Huntington’s disease

Objective Compromised brain cholesterol turnover and altered regulation of brain cholesterol metabolism have been allied with some neurodegenerative diseases, including Huntington’s disease (HD). Following our previous studies in HD, in this study we aim to investigate in vitro in a neuroblastoma cellular model of HD, the effect of CYP46A1 overexpression, an essential enzyme in cholesterol metabolism, on huntingtin aggregation and levels. Results We found that CYP46A1 reduces the quantity and size of mutant huntingtin aggregates in cells, as well as the levels of mutant huntingtin protein. Additionally, our results suggest that the observed beneficial effects of CYP46A1 in HD cells are linked to the activation of autophagy. Taken together, our results further demonstrate that CYP46A1 is a pertinent target to counteract HD progression.This work was supported by Brainvectis and E.rare: E-Rare Joint Transnational Call for Proposals 2017 “Transnational Research Projects for Innovative Therapeutic Approaches for Rare Diseases”. CN laboratory is supported by the French Muscular Dystrophy Association (AFM-Téléthon), the Ataxia UK, and the Fundação para a Ciência e Tecnologia (project ALG-01-0145-FEDER-29480 “SeGrPolyQ”). AM is supported by a Ph.D. fellowship from FCT (SFRH/BD/133192/2017)info:eu-repo/semantics/publishedVersio

Lifestyle, metabolic disorders and male hypogonadism - a one-way ticket?

Hypogonadism is more frequent among men with common metabolic diseases, notably obesity and type 2 diabetes. Indeed, endocrine disruption caused by metabolic diseases can trigger the onset of hypogonadism, although the underlying molecular mechanisms are not entirely understood. Metabolic diseases are closely related to unhealthy lifestyle choices, such as dietary habits and sedentarism. Therefore, hypogonadism is part of a pathological triad gathering unhealthy lifestyle, metabolic disease and genetic background. Additionally, hypogonadism harbors the potential to aggravate underlying metabolic disorders, further sustaining the mechanisms leading to disease. To what extent does lifestyle intervention in men suffering from these metabolic disorders can prevent, improve or reverse hypogonadism, is still controversial. Moreover, recent evidence suggests that the metabolic status of the father is related to the risk of inter and transgenerational inheritance of hypogonadism. In this review, we will address the proposed mechanisms of disease, as well as currently available interventions for hypogonadism.publishe

Construção e evidências iniciais de validade de uma escala brasileira de identificação nacional

Identidade social é parte do autoconceito de uma pessoa e é construída com base em caracte rísticas associadas a determinadas categorias sociais que o indivíduo faz parte. Atualmente, uma das mais salientes categorias de identidade social é a nacionalidade. O presente estudo apresenta uma nova medida de identificação nacional, desenvolvida para o contexto brasileiro. Para tanto, foram realizados dois estudos. O primeiro refere-se à construção do instrumento e à investigação de evidências iniciais de validade interna. Já o segundo estudo investigou novas evidências de validade interna e buscou evidências de validade com base nas relações com variáveis externas e teoricamente correlatas à identificação nacional. Os resultados de ambos os estudos indicaram evidências de validade de construto e de critério da escala. No entanto, outras evidências de validade ainda são necessárias para atestar a qualidade da escala de identificação nacional e sua real adequação para uso no contexto brasileiro

Assessment of ciprofloxacin photocatalysis by-products toxicity with Vibrio fischeri

The presence of pharmaceuticals in water has become a large concern due to the potential negative effects on humans and aquatic ecosystems. From these pharmaceuticals, antibiotics represent a serious problem since their overuse and misuse may lead to adverse environmental effects, in particular, toxicity to microflora and fauna and potential negative effects to humans [1]. Photocatalysis has become attractive to promote the degradation of contaminants in the aquatic environment since it allows their rapid and efficient removal from water, transforming them into by-products [2]. In order to evaluate toxicity of these by-products, several bio tests using bacteria (Vibrio fischeri) and algae (Daphnia spp.), among others, have been used [3]. In the present work a photocatalytic systems using commercial TiO2 and ZnO nanoparticles in suspension was used to degrade ciprofloxacin under UV radiation. Samples were withdraw over time in order to monitor degradation and toxicity. The luminescence of the bacteria Vibrio fischeri was used to test the toxicity of ciprofloxacin intermediate compounds, produced during the photocatalysis process. If a substance is toxic towards these bacteria, their normal luminescence decreases, as a consequence of a decreasing bacteria viability. Results (Figure 1) indicate that samples without ciprofloxacin degradation (t=0), in contact with bacteria (for 35 min), result in a higher luminescence than with completely degraded ciprofloxacin (t=15min). These results indicate that by products are responsible for low bacteria viability.FEDER through the COMPETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project PEST-C/FIS/UI607/2011 and project PTDC/CTM-NAN/121038/2010

Trypsin purification using magnetic azocasein composite

This contribution presents an inexpensive, simple and fast procedure to purify trypsin from fish viscera based on affinity binding onto magnetic particles of azocasein composite (MAzo). This casein derivative, nonspecific protease substrate, was magnetized by co-precipitation of Fe+2 and Fe+3 ions. Intestines of fish Nile tilapia (Oreochromis niloticus) were homogenized in 0.01 M Tris-HCl buffer, pH 8.0 (one gram of tissue/ml). Afterwards, the homogenate was partially purified with ammonium sulfate (20-40% of saturation), dialyzed and then incubated with MAzo. The adsorbed proteins were firstly extensively washed with 0.01 M Tris-HCl buffer, pH 8.0, and subsequently with 3 M NaCl by collecting the magnetic azocasein composite under a magnetic field. The fractions collected by these washings were used for protein and enzyme activity determinations as well as electrophoresis. The specific activity of the protein collected with 3 M NaCl (41.82 unit/mg) showed to be 220 times higher than that found for the crude extract (0.19 unit/mg). The SDS-PAGE showed that the size of the purified protein was approximately 24 kDa, agreeing with the previously reported for the Nile tilapia trypsin molecular weight. This procedure presents the advantages of magnetic azocasein compostite reuse and can be applied for trypsin purification from other sources

Expanding the potential of self-assembled silk fibroin as aerogel particles for tissue regeneration

A newly produced silk fibroin (SF) aerogel particulate system using a supercritical carbon dioxide (scCO2)-assisted drying technology is herein proposed for biomedical applications. Different concentrations of silk fibroin (3%, 5%, and 7% (w/v)) were explored to investigate the potential of this technology to produce size- and porosity-controlled particles. Laser diffraction, helium pycnometry, nitrogen adsorption–desorption analysis and Fourier Transform Infrared with Attenuated Total Reflectance (FTIR-ATR) spectroscopy were performed to characterize the physicochemical properties of the material. The enzymatic degradation profile of the SF aerogel particles was evaluated by immersion in protease XIV solution, and the biological properties by cell viability and cell proliferation assays. The obtained aerogel particles were mesoporous with high and concentration dependent specific surface area (203–326 m2/g). They displayed significant antioxidant activity and sustained degradation in the presence of protease XIV enzyme. The in vitro assessment using human dermal fibroblasts (HDF) confirm the particles’ biocompatibility, as well as the enhancement in cell viability and proliferation.info:eu-repo/semantics/publishedVersio

Clinicopathologic data of individuals with oral lichen planus : a Brazilian case series

The aim of the present series was to analyze the sociodemographic characteristics, clinicopathologic features, and oral health-related quality of life of 41 individuals with oral lichen planus (OLP). In a retrospective analysis (1998-2018), individuals with a clinical diagnosis of OLP from a referral service of Oral Medicine of Brazil were invited for follow-up. The individuals were assessed using the Oral Health Impact Profile-14 (OHIP-14) form. Histopathological data were reviewed according to the latest criteria proposed by the American Academy of Oral and Maxillofacial Pathology (AAOMP/2016). This series mainly consisted of females (70.7%) in their forties (31.7%). The buccal mucosa (68.2%) was the most commonly affected site. Reticular (56.1%) and erosive (34.3%) appearances were the most frequent. According to OHIP-14, individuals with OLP at multiple sites in the oral cavity showed worse values in the handicap domain and those who did not respond to corticosteroids showed a higher score on the psychological discomfort domain. The findings of the present study, using the AAOMP/2016 criteria, agree with case series and retrospective studies reported in the literature. Besides, OLP in its more severe clinical forms had an influence on patient quality of life

Optimization of plasma amplifiers

Plasma amplifiers offer a route to side-step limitations on chirped pulse amplification and generate laser pulses at the power frontier. They compress long pulses by transferring energy to a shorter pulse via the Raman or Brillouin instabilities. We present an extensive kinetic numerical study of the three-dimensional parameter space for the Raman case. Further particle-in-cell simulations find the optimal seed pulse parameters for experimentally relevant constraints. The high-efficiency self-similar behavior is observed only for seeds shorter than the linear Raman growth time. A test case similar to an upcoming experiment at the Laboratory for Laser Energetics is found to maintain good transverse coherence and high-energy efficiency. Effective compression of a 10 kJ , nanosecond-long driver pulse is also demonstrated in a 15-cm-long amplifier

a different view on light element anti correlations in globular clusters fluorine abundances in ngc 6656 m22

Observed chemical (anti)correlations in the light elements C, N, O, Na, Mg, and Al among globular cluster (GC) stars are presently recognised as the signature of self-pollution from previous generations of stars. This defines the multiple population scenario (MPS). Since fluorine is involved in the complete CNO cycle, determining its abundance in GCs provides new and complementary clues regarding the nature of these previous generations. In fact, along with the Na-O and Mg-Al anti-correlations, the MPS also predicts an anti-correlation between F and Na and a positive correlation between F and O. Furthermore, theoretical models suggest that low-mass (≲5Mȯ) asymptotic giant branch (AGB) stars are F producers (and are also responsible for C+N+O and s-process element variations). We present our results on near-infrared CRIRES spectroscopic observations of six giant stars in the metal-poor GC NGC 6656 (M22): we aim at inferring the F content and its (possible) variation in this GC, which exhibits a rather peculiar abundance pattern, with variations in both light (C, N, O, Na, Mg, Al) and heavy (Fe-peak and s-process) elements. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence