Chemical Composition and Cytoprotective Activities of Methanolic Extract of Asplenium adiantum-nigrum L. (Aspleniaceae)

Ferns can be a source of polyphenolic compounds, with the fronds being the main parts described in ethnopharmacological studies. The present study screened polyphenolic phytochemicals and evaluated in vitro activities of a methanolic extract of Asplenium adiantum-nigrum L. fronds (AAM), an Aspleniaceae fern collected from the Prades mountains (Tarragona, Spain). Phytocharacterization by HPLC-MS/MS confirmed that the major flavonoids isolated in AAM are flavanols while the major phytochemicals are phenol acids, with chlorogenic acid being the most representative one. Cytotoxicity, cytoprotection, cellular repair activity, and phototoxicity were determined in vitro in the presence of 0.01, 0.1, and 1 mg/mL of the extract. No cytotoxicity was obtained in any of the cell lines tested: non-tumoral (3T3 and HaCaT) and tumoral (HeLa, HepG2, and A549) cells. Additionally, the polyphenolic extract showed greater protective effect against H2O2 in 3T3 than HaCaT cells. Despite the low total phenolic content of AAM (1405.68 mg phenolic phytochemicals/kg dry extract), the cytoprotective activity of this extract could be associated with the synergistic antioxidant action of their polyphenolic profile. In addition, the extract did not present phototoxicity against the non-cytotoxic 1.8 J/cm2 dose of UVA light in both non-tumoral cell lines

The transition of medical students through residency: Effects on physical activity and other lifestyle-related behaviors

© 2016 Human Kinetics, Inc.Background: Little is known about lifestyle choices and preventive healthcare-seeking behaviors during the transition from medical school graduation to residency training, a period characterized by increased rates of stress and lack of free time due to demanding working conditions. All of these issues are likely to affect physical activity (PA) level. This study explored the evolution of PA and other lifestyle behaviors during this transition. Methods: A cross-sectional study and a cohort study were conducted with medical students (2010) and physicians before and after the first year of residency (2013 and 2014). A self-administered questionnaire assessed PA, health and lifestyle behaviors. Results: From a sample of 420 medical students and 478 residents, 74%comply with current PA guidelines. PA decreased by 16%during residency. Low levels of PA were found among (i) females and in respondents who reported (ii) poor self-perceived health and (iii) unhealthy body weight (P <.05). Low PA level was also significantly associated with poor mental health in first-year residents. Conclusions: The transition has a negative effect on physicians' PA level that may affect physicians' own health and patient care. Medical programs should encourage residents to engage in PA to assure physicians' personal and mental health

Mechanisms underlying cytotoxicity induced by engineered nanomaterials: a review of in vitro studies

Engineered nanomaterials are emerging functional materials with technologically interesting properties and a wide range of promising applications, such as drug delivery devices, medical imaging and diagnostics, and various other industrial products. However, concerns have been expressed about the risks of such materials and whether they can cause adverse effects. Studies of the potential hazards of nanomaterials have been widely performed using cell models and a range of in vitro approaches. In the present review, we provide a comprehensive and critical literature overview on current in vitro toxicity test methods that have been applied to determine the mechanisms underlying the cytotoxic effects induced by the nanostructures. The small size, surface charge, hydrophobicity and high adsorption capacity of nanomaterial allow for specific interactions within cell membrane and subcellular organelles, which in turn could lead to cytotoxicity through a range of different mechanisms. Finally, aggregating the given information on the relationships of nanomaterial cytotoxic responses with an understanding of its structure and physicochemical properties may promote the design of biologically safe nanostructures

Trapping and ground-state cooling of H2+H_2^+

We demonstrate co-trapping and sideband cooling of a $H_2^+ - ^9Be^+$ ion pair in a cryogenic Paul trap. We study the chemical lifetime of $H_2^+$ and its dependence on the apparatus temperature, achieving lifetimes of up to $11^{+6}_{-3} h$ at 10 K. We demonstrate cooling of translational motion to an average phonon number of 0.07(1), corresponding to a temperature of $22(1)\mu K$. Our results provide a basis for quantum logic spectroscopy experiments of $H_2^+$, as well as other light ions such as $HD^+$, $H_3^+$, and $He^+$

Physical activity level and lifestyle-related risk factors from Catalan physicians.

BACKGROUND: Physicians' own Physical Activity (PA) and other health-related habits influence PA promotion. The current study identifies the PA level, according to the current PA recommendations and other health-related habits of physicians from the Catalan Medical Council. METHODS: 2400 physicians (30-55 years) were randomly selected; each received a self-administered mailed questionnaire identifying medical specialization, work setting, health self-perception, body mass index (BMI), PA, and smoking habits. RESULTS: 762 physicians responded (52% female). Almost 1 in 2 (49.3%) exercised sufficiently, nearly all self-perceived good health, while 80.5% were nonsmokers. Almost 6 in 10 males reported overweight or obesity (56.9%) versus 18.2% of females. Active physicians dominated specific groups: (1) aged 45-55 years, (2) specializing either in primary care or surgery, (3) working in the private sector, (4) BMI < 25 kg/m2, (5) perceiving themselves in good health, or (6) having free leisure time. CONCLUSIONS: Only half of Catalan physicians met current PA recommendations; male physicians were particularly at risk for overweight/obesity. Overweight and under-exercise were associated with private workplaces and positive health perceptions, meaning that it is it is now possible to target inactive and/or overweight Catalan physicians in future interventions

Erythrocytes and cell line-based assays to evaluate the cytoprotective activity of antioxidant components obtained from natural sources

Oxidative stress can damage cellular components including DNA, proteins or lipids, and may cause several skin diseases. To protect from this damage and addressing consumer's appeal to natural products, antioxidants obtained from algal and vegetal extracts are being proposed as antioxidants to be incorporated into formulations. Thus, the development of reliable, quick and economic in vitro methods to study the cytoactivity of these products is a meaningful requirement. A combination of erythrocyte and cell line-based assays was performed on two extracts from Sargassum muticum, one from Ulva lactuca, and one from Castanea sativa. Antioxidant properties were assessed in erythrocytes by the TBARS and AAPH assays, and cytotoxicity and antioxidant cytoprotection were assessed in HaCaT and 3T3 cells by the MTT assay. The extracts showed no antioxidant activity on the TBARS assay, whereas their antioxidant capacity in the AAPH assay was demonstrated. On the cytotoxicity assays, extracts showed low toxicity, with IC50 values higher than 200 µg/mL. C. sativa extract showed the most favourable antioxidant properties on the antioxidant cytoprotection assays; while S. muticum and U. lactuca extracts showed a low antioxidant activity. This battery of methods was useful to characterize the biological antioxidant properties of these natural extracts

A normal genetic variation modulates synaptic MMP-9 protein levels and the severity of schizophrenia symptoms

Abstract Matrix metalloproteinase 9 (MMP‐9) has recently emerged as a molecule that contributes to pathological synaptic plasticity in schizophrenia, but explanation of the underlying mechanisms has been missing. In the present study, we performed a phenotype‐based genetic association study (PGAS) in > 1,000 schizophrenia patients from the Göttingen Research Association for Schizophrenia (GRAS) data collection and found an association between the MMP‐9 rs20544 C/T single‐nucleotide polymorphism (SNP) located in the 3′untranslated region (UTR) and the severity of a chronic delusional syndrome. In cultured neurons, the rs20544 SNP influenced synaptic MMP‐9 activity and the morphology of dendritic spines. We demonstrated that Fragile X mental retardation protein (FMRP) bound the MMP‐9 3′UTR. We also found dramatic changes in RNA structure folding and alterations in the affinity of FMRP for MMP‐9 RNA, depending on the SNP variant. Finally, we observed greater sensitivity to psychosis‐related locomotor hyperactivity in Mmp‐9 heterozygous mice. We propose a novel mechanism that involves MMP‐9‐dependent changes in dendritic spine morphology and the pathophysiology of schizophrenia, providing the first mechanistic insights into the way in which the single base change in the MMP‐9 gene (rs20544) influences gene function and results in phenotypic changes observed in schizophrenia patients

Radio data challenge the broadband modelling of GRB160131A afterglow

Context. Gamma-ray burst (GRB) afterglows originate from the interaction between the relativistic ejecta and the surrounding medium. Consequently, their properties depend on several aspects: radiation mechanisms, relativistic shock micro-physics, circumburst environment, and the structure and geometry of the relativistic jet. While the standard afterglow model accounts for the overall spectral and temporal evolution for a number of GRBs, its validity limits emerge when the data set is particularly rich and constraining, especially in the radio band. Aims. We aimed to model the afterglow of the long GRB160131A (redshift $z = 0.972$), for which we collected a rich, broadband, and accurate data set, spanning from $6\times10^{8}$ to $7\times10^{17}$ Hz in frequency, and from 330 s to 160 days post burst in time. Methods. We modelled the spectral and temporal evolution of this GRB afterglow through two approaches: the adoption of empirical functions to model optical/X-rays data set, later assessing their compatibility with the radio domain; the inclusion of the entire multi-frequency data set simultaneously through the Python package named sAGa (Software for AfterGlow Analysis), to come up with an exhaustive and self-consistent description of the micro-physics, geometry, and dynamics of the afterglow. Results. From deep broadband analysis (from radio to X-ray frequencies) of the afterglow light curves, GRB160131A outflow shows evidence of jetted emission. Moreover, we observe dust extinction in the optical spectra, and energy injection in the optical/X-ray data. Radio spectra are characterised by several peaks, that could be due to either interstellar scintillation (ISS) effects or a multi-component structure. Conclusions. The inclusion of radio data in the broadband set of GRB160131A makes a self-consistent modelling hardly attainable within the standard model of GRB afterglows.Comment: 36 pages, 16 figures, 8 tables, accepted by A&A; v2: updated Acknowledgement