95 research outputs found
Composition of bioactive secondary metabolites and mutagenicity of Sambucus nigra L. Fruit at different stages of ripeness
The relationship between the content of bioactive compounds and mutagenic activity of elderberry fruit at different stages of ripeness was investigated. Significant differences in the antioxidant profiles (TLC, HPLC with post-column derivatization) and antioxidant activity (ABTS, DPPH, and FC tests) were observed for studied elderberry extracts. The more ripen the fruit at the time of harvest were, the higher the content of anthocyanins (increase from 0 to 7.8 mg g−1d.w.) and antioxidant activity of the extracts (about 5-fold increase) were. Cyanogenic glycosides were not detected at any stage of ripeness. Accordingly, Ames MPF test (Xenometrix) did not reveal any mutagenicity. Our study suggests that instability of cyanogenic glycosides ensures safety of food/pharmaceutical products based on even not fully ripen elderberry fruit
The Council of Europe's Approach towards Ageism
In this chapter, I examine the degree of interest in ageism among Council of
Europe members, and the degree of interest in its elimination through the Council
of Europe forum. I also examine the interpretation of the concept of ageism by various
Council of Europe institutions. Finally, I explore the Council’s willingness and
ability to eliminate or at least mitigate ageism effect
Virulence factors of Enterococcus strains isolated from patients with inflammatory bowel disease
Author contributions: Golińska E performed the majority of the experiments, including the detection of gelatinase activity, measurement of hydrogen peroxide production and the determination of hydrogen peroxide decomposition, and wrote the manuscript; Tomusiak A collected and analysed the data; Gosiewski T performed PCR and multiplex PCR; Więcek G evaluated the adherence to human gut epithelium cells; Machul A and Mikołajczyk D evaluated the biofilm production; Heczko PB and Bulanda M supervised the experiments; and Strus M designed the experiments and supervised the project. Abstract AIM: To determine the features of Enterococcus that contribute to the development and maintenance of the inflammatory process in patients with inflammatory bowel disease (IBD). METHODS: Multiplex polymerase chain reaction (PCR) was applied to assess the presence of genes that encode virulence factors [surface aggregating protein (asa1 ), gelatinase (gelE ), cytolysin (cylA ), extracellular surface protein (esp ) and hyaluronidase (hyl )] in the genomic DNA of 28 strains of Enterococcus isolated from the intestinal tissues of children with IBD (n = 16) and of children without IBD (controls; n = 12). Additionally, strains with confirmed presence of the gelE gene were tested by PCR for the presence of quorum sensing genes (fsrA , fsrB , fsrC ) that control the gelatinase production. Gelatinase activity was tested on agar plates containing 1.6% gelatin. We also analysed the ability of Enterococcus strains to release and decompose hydrogen peroxide (using Analytical Merckoquant peroxide test strips) and tested their ability to adhere to Caco-2 human gut epithelium cells and form biofilms in vitro . RESULTS: A comparison of the genomes of Enterococcus strains isolated from the inflamed mucosa of patients with IBD with those of the control group showed statistically significant differences in the frequency of the asa1 gene and the gelE gene. Furthermore, the cumulative occurrence of different virulence genes in the genome of a single strain of Enterococcus isolated from the IBD patient group is greater than in a strain from the control group, although no significant difference was found. Statistically significant differences in the decomposition of hydrogen peroxide and adherence to the Caco-2 epithelial cell line between the strains from the patient group and control group were demonstrated. The results also showed that profuse biofilm production was more frequent among Enterococcus strains isolated from children with IBD than in control strains. CONCLUSION: Enterococcus strains that adhere strongly to the intestinal epithelium, form biofilms and possess antioxidant defence mechanisms seem to have the greatest influence on the inflammatory process
Pseudomonas aeruginosa biofilm is a potent inducer of phagocyte hyperinflammation
OBJECTIVE: Pseudomonas aeruginosa effectively facilitate resistance to phagocyte killing by biofilm formation. However, the cross talk between biofilm components and phagocytes is still unclear. We hypothesize that a biofilm provides a concentrated extracellular source of LPS, DNA and exopolysaccharides (EPS), which polarize neighbouring phagocytes into an adverse hyperinflammatory state of activation. METHODS: We measured the release of a panel of mediators produced in vitro by murine neutrophils and macrophages exposed to various biofilm components of P. aeruginosa cultures. RESULTS: We found that conditioned media from a high biofilm-producing strain of P. aeruginosa, PAR5, accumulated high concentrations of extracellular bacterial LPS, DNA and EPS by 72 h. These conditioned media induced phagocytes to release a hyperinflammatory pattern of mediators, with enhanced levels of TNF-α, IL-6, IL12p40, PGE2 and NO. Moreover, the phagocytes also upregulated COX-2 and iNOS with no influence on the expression of arginase-1. CONCLUSIONS: Phagocytes exposed to biofilm microenvironment, called by us biofilm-associated neutrophils/macrophages (BANs/BAMs), display secretory properties similar to that of N1/M1-type phagocytes. These results suggest that in vivo high concentrations of LPS and DNA, trapped in biofilm by EPS, might convert infiltrating phagocytes into cells responsible for tissue injury without direct contact with bacteria and phagocytosis
Catalogue of BRITE-Constellation targets I. Fields 1 to 14 (November 2013 - April 2016)
The BRIght Target Explorer (BRITE) mission collects photometric time series
in two passbands aiming to investigate stellar structure and evolution. Since
their launches in the years 2013 and 2014, the constellation of five BRITE
nano-satellites has observed a total of more than 700 individual bright stars
in 64 fields. Some targets have been observed multiple times. Thus, the total
time base of the data sets acquired for those stars can be as long as nine
years. Our aim is to provide a complete description of ready-to-use BRITE data,
to show the scientific potential of the BRITE-Constellation data by identifying
the most interesting targets, and to demonstrate and encourage how scientists
can use these data in their research. We apply a decorrelation process to the
automatically reduced BRITE-Constellation data to correct for instrumental
effects. We perform a statistical analysis of the light curves obtained for the
300 stars observed in the first 14 fields during the first ~2.5 years of the
mission. We also perform cross-identification with the International Variable
Star Index. We present the data obtained by the BRITE-Constellation mission in
the first 14 fields it observed from November 2013 to April 2016. We also
describe the properties of the data for these fields and the 300 stars observed
in them. Using these data, we detected variability in 64% of the presented
sample of stars. Sixty-four stars or 21.3% of the sample have not yet been
identified as variable in the literature and their data have not been analysed
in detail. They can therefore provide valuable scientific material for further
research. All data are made publicly available through the BRITE Public Data
Archive and the Canadian Astronomy Data Centre.Comment: accepted by Astronomy & Astrophysics, 13 pages main text, 22 pages of
appendi
Long-range corrected DFT calculations of charge-transfer integrals in model metal-free phthalocyanine complexes
An assessment of several widely used exchange--correlation potentials in computing charge-transfer integrals is performed. In particular, we employ the recently proposed Coulomb-attenuated model which was proven by other authors to improve upon conventional functionals in the case of charge-transfer excitations. For further validation, two distinct approaches to compute the property in question are compared for a phthalocyanine dimer
Catechol-O-Methyltransferase Val158Met Polymorphism Associates with Individual Differences in Sleep Physiologic Responses to Chronic Sleep Loss
Val158Met polymorphism was a novel marker in healthy adults of differential vulnerability to chronic partial sleep deprivation (PSD), a condition distinct from total sleep loss and one experienced by millions on a daily and persistent basis. allelic frequencies were higher in whites than African Americans.-related treatment responses and risk factors for symptom exacerbation
TESS Cycle 2 observations of roAp stars with 2-min cadence data
We present the results of a systematic search of the Transiting Exoplanet
Survey Satellite (TESS) 2-min cadence data for new rapidly oscillating Ap
(roAp) stars observed during the Cycle 2 phase of its mission. We find seven
new roAp stars previously unreported as such and present the analysis of a
further 25 roAp stars that are already known. Three of the new stars show
multiperiodic pulsations, while all new members are rotationally variable
stars, leading to almost 70 per cent (22) of the roAp stars presented being
CVn-type variable stars. We show that targeted observations of known
chemically peculiar stars are likely to overlook many new roAp stars, and
demonstrate that multi-epoch observations are necessary to see pulsational
behaviour changes. We find a lack of roAp stars close to the blue edge of the
theoretical roAp instability strip, and reaffirm that mode instability is
observed more frequently with precise, space-based observations. In addition to
the Cycle 2 observations, we analyse TESS data for all known roAp stars. This
amounts to 18 further roAp stars observed by TESS. Finally, we list six known
roAp stars that TESS is yet to observe. We deduce that the incidence of roAp
stars amongst the Ap star population is just 5.5 per cent, raising fundamental
questions about the conditions required to excite pulsations in Ap stars. This
work, coupled with our previous work on roAp stars in Cycle 1 observations,
presents the most comprehensive, homogeneous study of the roAp stars in the
TESS nominal mission, with a collection of 112 confirmed roAp stars in total.Comment: Accepted for publication in MNRAS. 32 Pages, 2 Tables, 77 Figure
Eating disorders: the current status of molecular genetic research
Anorexia nervosa (AN) and bulimia nervosa (BN) are complex disorders characterized by disordered eating behavior where the patient’s attitude towards weight and shape, as well as their perception of body shape, are disturbed. Formal genetic studies on twins and families suggested a substantial genetic influence for AN and BN. Candidate gene studies have initially focused on the serotonergic and other central neurotransmitter systems and on genes involved in body weight regulation. Hardly any of the positive findings achieved in these studies were unequivocally confirmed or substantiated in meta-analyses. This might be due to too small sample sizes and thus low power and/or the genes underlying eating disorders have not yet been analyzed. However, some studies that also used subphenotypes (e.g., restricting type of AN) led to more specific results; however, confirmation is as yet mostly lacking. Systematic genome-wide linkage scans based on families with at least two individuals with an eating disorder (AN or BN) revealed initial linkage regions on chromosomes 1, 3 and 4 (AN) and 10p (BN). Analyses on candidate genes in the chromosome 1 linkage region led to the (as yet unconfirmed) identification of certain variants associated with AN. Genome-wide association studies are under way and will presumably help to identify genes and pathways involved in these eating disorders. The elucidation of the molecular mechanisms underlying eating disorders might improve therapeutic approaches
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