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Role of AGAP2 in the profibrogenic effects induced by TGFβ in LX-2 hepatic stellate cells
Liver damage induces hepatic stellate cells (HSC) activation, characterised by a fibrogenic, proliferative and migratory phenotype. Activated HSC are mainly regulated by transforming growth factor β 1 (TGFβ1), which increases the production of extracellular matrix proteins (e.g. collagen-I) promoting the progression of hepatic fibrosis. AGAP2 (ArfGAP with GTPase domain, ankyrin repeat and PH domain 2) is a GTPase/GTP-activating protein involved in the actin remodelling system and receptor recycling. In the present work the role of AGAP2 in human HSC in response to TGFβ1 was investigated. LX-2 HSC were transfected with AGAP2 siRNA and treated with TGFβ1. AGAP2 knockdown prevented to some extent the proliferative and migratory TGFβ1-induced capacities of LX-2 cells. An array focused on human fibrosis revealed that AGAP2 knockdown partially prevented TGFβ1-mediated gene expression of the fibrogenic genes ACTA2, COL1A2, EDN1, INHBE, LOX, PDGFB, TGFΒ12, while favored the expression of CXCR4, IL1A, MMP1, MMP3 and MMP9 genes. Furthermore, TGFβ1 induced AGAP2 promoter activation and its protein expression in LX-2. In addition, AGAP2 silencing affected TGFβ1-receptor 2 (TGFR2) trafficking in U2OS cells, blocking its effective recycling to the membrane. AGAP2 silencing in LX-2 cells prevented the TGFβ1-induced increase of collagen-I protein levels, while its over-expression enhanced collagen I protein expression in the presence or absence of the cytokine. AGAP2 overexpression also increased focal adhesion kinase (FAK) phosphorylated levels in LX-2 cells. FAK and MEK1 inhibitors prevented the increase of collagen-I expression caused by TGFβ1 in LX-2 overexpressing AGAP2. In summary, the present work shows for the first time, that AGAP2 is a potential new target involved in TGFβ1 signalling, contributing to the progression of hepatic fibrosis
Impact of Liver Inflammation on Bile Acid Side Chain Shortening and Amidation
Bile acid (BA) synthesis from cholesterol by hepatocytes is inhibited by inflammatory cytokines. Whether liver inflammation also affects BA side chain shortening and conjugation was investigated. In human liver cell lines (IHH, HepG2, and HepaRG), agonists of nuclear receptors including the farnesoid X receptor (FXR), liver X receptor (LXR), and peroxisome proliferator-activated receptors (PPARs) did not affect the expression of BA-related peroxisomal enzymes. In contrast, hepatocyte nuclear factor 4? (HNF4?) inhibition down-regulated acyl-CoA oxidase 2 (ACOX2). ACOX2 was repressed by fibroblast growth factor 19 (FGF19), which was prevented by extracellular signal-regulated kinase (ERK) pathway inhibition. These changes were paralleled by altered BA synthesis (HPLC-MS/MS). Cytokines able to down-regulate cholesterol-7?-hydroxylase (CYP7A1) had little effect on peroxisomal enzymes involved in BA synthesis except for ACOX2 and bile acid-CoA:amino acid N-acyltransferase (BAAT), which were down-regulated, mainly by oncostatin M (OSM). This effect was prevented by Janus kinase (JAK) inhibition, which restored BA side chain shortening and conjugation. The binding of OSM to the extracellular matrix accounted for a persistent effect after culture medium replacement. In silico analysis of four databases (n = 201) and a validation cohort (n = 90) revealed an inverse relationship between liver inflammation and ACOX2/BAAT expression which was associated with changes in HNF4? levels. In conclusion, BA side chain shortening and conjugation are inhibited by inflammatory effectors. However, other mechanisms involved in BA homeostasis counterbalance any significant impact on the serum BA profile
Transferrin uptake may occur through detergent-resistant membrane domains at the cytopharynx of Trypanosoma cruzi epimastigote forms
Quantitative-spatial assessment of soil contamination in S. Francisco de Assis due to mining activity of the Panasqueira mine (Portugal)
Through the years, mining and beneficiation processes produces large amounts of As-rich mine wastes laid up in huge tailings and open-air impoundments
(Barroca Grande and Rio tailings) that are the main source of pollution in the surrounding area once they are exposed to the weathering conditions leading to
the formation of AMD and consequently to the contamination of the surrounding environments, in particularly soils. In order to investigate the environmental
contamination impact on S. Francisco de Assis (village located between the two major impoundments and tailings) agricultural soils, a geochemical survey was
undertaken to assess toxic metals associations, related levels and their spatial distribution, and to identify the possible contamination sources. According to
the calculated contamination factor, As and Zn have a very high contamination factor giving rise to 65.4 % of samples with a moderate to high pollution
degree; 34.6 % have been classified as nil to very low pollution degree. The contamination factor spatial distribution put in evidence the fact that As, Cd, Cu,
Pb, and Zn soils contents, downstream Barroca Grande tailing, are increased when compared with the local Bk soils. The mechanical dispersion, due to
erosion, is the main contamination source. The chemical extraction demonstrates that the trace metals distribution and accumulation in S. Francisco de Assis
soils is related to sulfides, but also to amorphous or poorly crystalline iron oxide phases. The partitioning study allowed understanding the local chemical
elements mobility and precipitation processes, giving rise to the contamination dispersion model of the study area. The wind and hydrological factors are
responsible for the chemical elements transport mechanisms, the water being the main transporter medium and soils as one of the possible retention media
A simple score to predict early severe infections in patients with newly diagnosed multiple myeloma
Accelerated inbreeding depression suggests synergistic epistasis for deleterious mutations in Drosophila melanogaster
Epistasis may have important consequences for a number of issues in quantitative genetics and evolutionary biology. In
particular, synergistic epistasis for deleterious alleles is relevant to the mutation load paradox and the evolution of sex and
recombination. Some studies have shown evidence of synergistic epistasis for spontaneous or induced deleterious mutations
appearing in mutation-accumulation experiments. However, many newly arising mutations may not actually be segregating
in natural populations because of the erasing action of natural selection. A demonstration of synergistic epistasis for naturally
segregating alleles can be achieved by means of inbreeding depression studies, as deleterious recessive allelic effects are
exposed in inbred lines. Nevertheless, evidence of epistasis from these studies is scarce and controversial. In this paper, we
report the results of two independent inbreeding experiments carried out with two different populations of Drosophila
melanogaster. The results show a consistent accelerated inbreeding depression for fitness, suggesting synergistic epistasis
among deleterious alleles. We also performed computer simulations assuming different possible models of epistasis and
mutational parameters for fitness, finding some of them to be compatible with the results observed. Our results suggest that
synergistic epistasis for deleterious mutations not only occurs among newly arisen spontaneous or induced mutations, but
also among segregating alleles in natural populationsWe acknowledge the support by Uvigo
Marine Research Centre funded by the “Excellence in Research
(INUGA)” Programme from the Regional Council of Culture, Education and Universities, with co-funding from the European Union
through the ERDF Operational Programme Galicia 2014-2020. This
work was funded by Agencia Estatal de Investigación (AEI) (CGL2016-75904-C2-1-P), Xunta de Galicia (ED431C 2016-037) and
Fondos Feder: “Unha maneira de facer Europa.” SD was founded by a
predoctoral (FPI) grant from Ministerio de Economía y
Competitividad, SpainS
On the Evolutionary Modification of Self-Incompatibility: Implications of Partial Clonality for Allelic Diversity and Genealogical Structure
Experimental investigations of homomorphic self-incompatibility (SI) have revealed an unanticipated level of complexity in its expression, permitting fine regulation over the course of a lifetime or a range of environmental conditions. Many flowering plants express some level of clonal reproduction, and phylogenetic analyses suggest that clonality evolves in a correlated fashion with SI in Solanum (Solanaceae). Here, we use a diffusion approximation to explore the effects on the evolutionary dynamics of SI of vegetative propagation with SI restricted to reproduction through seed. While clonality reduces the strength of frequency-dependent selection maintaining S-allele diversity, much of the great depth typical of S-allele genealogies is preserved. Our results suggest that clonality can play an important role in the evolution of SI systems, and may afford insight into unexplained features of allele genealogies in the Solanaceae
Physical Activity Patterns of the Spanish Population Are Mostly Determined by Sex and Age: Findings in the ANIBES Study
Background
Representative data for the Spanish population regarding physical activity (PA) behaviors
are scarce and seldom comparable due to methodological inconsistencies.
Aim
Our objectives were to describe the PA behavior by means of the standardized self-reported
International Physical Activity Questionnaire (IPAQ) and to know the proportion of the Spanish
population meeting and not meeting international PA recommendations.
Material and Methods
PA was assessed using the IPAQ in a representative sample of 2285 individuals (males,
50.4%) aged 9–75 years and living in municipalities of at least 2,000 inhabitants. Data were
analyzed according to: age groups 9–12, 13–17, 18–64, and 65–75 years; sex; geographical
distribution; locality size and educational levels.
Results
Mean total PA was 868.8±660.9 min/wk, mean vigorous PA 146.4±254.1 min/wk, and mean
moderate PA 398.1±408.0 min/wk, showing significant differences between sexes
(p<0.05). Children performed higher moderate-vigorous PA than adolescents and seniors
(p<0.05), and adults than adolescents and seniors (p<0.05). Compared to recommendations,
36.2%of adults performed <150 min/week of moderate PA, 65.4% <75 min/week of vigorous PA and 27.0%did not perform any PA at all, presenting significant differences
between sexes (p<0.05). A total of 55.4%of children and adolescents performed less than
420 min/week of MVPA, being higher in the later (62.6%) than in the former (48.4%). Highest
non-compliance was observed in adolescent females (86.5%).
Conclusion
Sex and age are the main influencing factors on PA in the Spanish population. Males
engage in more vigorous and light PA overall, whereas females perform more moderate
PA. PA behavior differs between age groups and no clear lineal increase with age could be
observed. Twenty-seven percent of adults and 55.4% of children and adolescents do not
meet international PA recommendations. Identified target groups should be addressed to
increase PA in the Spanish populationCoca-Cola Iberia through Spanish Nutrition Foundation (FEN)Coca-Cola Iberi
Study protocol for a pragmatic randomised controlled trial in general practice investigating the effectiveness of acupuncture against migraine
<p>Abstract</p> <p>Background</p> <p>Migraine is a chronic neurologic disease that can severely affect the patient's quality of life. Although in recent years many randomised studies have been carried out to investigate the effectiveness of acupuncture as a treatment for migraine, it remains a controversial issue. Our aim is to determine whether acupuncture, applied under real conditions of clinical practice in the area of primary healthcare, is more effective than conventional treatment.</p> <p>Methods/Design</p> <p>The design consists of a pragmatic multi-centre, three-armed randomised controlled trial, complemented with an economic evaluation of the results achieved, comparing the effectiveness of verum acupuncture with sham acupuncture, and with a control group receiving normal care only.</p> <p>Patients eligible for inclusion will be those presenting in general practice with migraine and for whom their General Practitioner (GP) is considering referral for acupuncture. Sampling will be by consecutive selection, and by randomised allocation to the three branches of the study, in a centralised way following a 1:1:1 distribution (verum acupuncture; sham acupuncture; conventional treatment). Secondly, one patient in three will be randomly selected from each of the acupuncture (verum or sham) groups for a brain perfusion study (by single photon emission tomography). The treatment with verum acupuncture will consist of 8 treatment sessions, once a week, at points selected individually by the acupuncturist. The sham acupuncture group will receive 8 sessions, one per week, with treatment being applied at non-acupuncture points in the dorsal and lumbar regions, using the minimal puncture technique. The control group will be given conventional treatment, as will the other two groups.</p> <p>Discussion</p> <p>This trial will contribute to available evidence on acupuncture for the treatment of migraine. The primary endpoint is the difference in the number of days with migraine among the three groups, between the baseline period (the 4 weeks prior to the start of treatment) and the period from weeks 9 to 12. As a secondary aspect, we shall record the index of laterality and the percentage of change in the mean count per pixel in each region of interest measured by the brain perfusion tomography, performed on a subsample of the patients within the real and sham acupuncture groups.</p> <p>Trial registration</p> <p>Current Controlled Trials ISRCTN98703707.</p
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