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101.
Hochdörfer T Kuhny M Zorn CN Hendriks RW Vanhaesebroeck B Bohnacker T Krystal G Huber M 《Cellular signalling》2011,23(5):866-875
Recognition of bacterial constituents by mast cells (MCs) is dependent on the presence of pattern recognition receptors, such as Toll-like receptors (TLRs). The final cellular response, however, depends on the influence of multiple environmental factors. In the current study we tested the hypothesis that the PI3K-activating ligands insulin-like growth factor-1 (IGF-1), insulin, antigen, and Steel Factor (SF) are able to modulate the TLR4-mediated production of proinflammatory cytokines in murine MCs. Costimulation with any of these ligands caused increased LPS-triggered secretion of IL-6 and TNF-α, but attenuated the production of IL-1β, though all three cytokines were produced in an NFκB-dependent manner. The pan-specific PI3K-inhibitor Wortmannin reverted the altered production of these cytokines. In agreement, MCs deficient for SHIP1, a negative regulator of the PI3K pathway, showed augmented secretion of IL-6/TNF-α and reduced production of IL-1β in response to LPS alone. The differential effects of IGF-1 on TLR4-mediated cytokine production were also observed in the context of TLR2 and IL-33 receptor-mediated MC activation. Importantly, these effects were seen in both bone marrow-derived and peritoneal MCs, suggesting general relevance for MCs. Using pharmacological and genetic tools, we could show that the p110δ isoform of PI3K is strongly implicated in SF-triggered suppression of LPS-induced IL-1β production. Costimulation with antigen was affected to a lesser extent. In conclusion, NFκB-dependent production of proinflammatory cytokines in MCs is differentially controlled by PI3K-activating ligand/receptor systems. 相似文献
102.
Aim The increasing number and availability of online databases of alien species beg a question of their comparability given most do not adopt standard criteria in the definition of species status or taxonomic treatment and vary in their comprehensiveness. In this study, we compare the consistency of two major European databases for the regions they have in common. We assess whether they use consistent terminology to classify species status, provide similar taxonomic classification and coverage, deliver comparable estimates of alien richness per country and identify comparable correlates of alien richness. Location Northern Europe. Methods Data on the total number of alien species as well as the number of established alien species were extracted from the online databases DAISIE and NOBANIS for 13 European countries and classified into comparable taxonomic groups. Analyses across countries examined trends in alien species richness, correlations among taxonomic groups and the explanatory power of population density, country area and per capita GDP on alien species richness. Results Alien species richness, intertaxon correlations and the significance of individual drivers of invasion were all strongly database dependent. Differences were more marked for total numbers of aliens than established aliens. Over all taxonomic groups, DAISIE had lower species richness and fewer significant intertaxon correlations but presented a greater number of significant explanatory models of alien species richness. Trends in species richness were not generally correlated between the two databases with human population density being a more important driver in DAISIE while country area had greater explanatory power in NOBANIS. Main conclusions Considerable caution should be applied when collating data from different databases because often their underlying structure and content may differ markedly. For Europe, the analysis indicates that having two contrasting databases is not an ideal basis for implementing invasive species policy and moves should be made soon to establish a central pan‐European database. 相似文献
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Analysis of historic changes in regional ecosystem service provisioning using land use data 总被引:2,自引:0,他引:2
Land use change has a major impact on goods and services that our environment supplies for society. While detailed ecological or biophysical field studies are needed to quantify the exact amount of ecosystem service supply at local scales, such a monitoring might be unfeasible at the regional scale. Since field scale monitoring schemes for ecosystem services or ecosystem functioning are missing, proxy based indicators can help to assess the historic development of ecosystem services or ecosystem functioning at the regional scale. We show at the example of the historic development (1964–2004) in the district of Leipzig/Germany how land use/land cover data can be used to derive regional scale indicators for ecosystem functions. We focus thereby on two hypotheses: (1) the ecosystem functioning has degraded over time and (2) changes in land use configuration play an important role in this degradation. The study focuses on indicators for ecosystem functions related to (i) water purification by riparian buffer strips, (ii) pollination, (iii) food production and (iv) outdoor recreation. Each indicator builds on the analysis of land use configuration and land use composition information and is tested on sensitivity/robustness with respect to parameters which had to be estimated based on expert knowledge. We show that land use composition is an important aspect in our ecosystem service assessment. Although our study region is faced with a maximum land use change of 11% in the major land use classes between 1964 and 2004, we see a decrease of ecosystem function indicators up to 23%. The regional assessment shows an overall trend for degradation of ecosystem functioning from 1964 to 1984. This trend is reversed between 1984 and 1994 but the process slowed down until 2004 without reaching the level of 1964. 相似文献
104.
von Ruesten A Steffen A Floegel A van der A DL Masala G Tjønneland A Halkjaer J Palli D Wareham NJ Loos RJ Sørensen TI Boeing H 《PloS one》2011,6(11):e27455
Objective
To investigate trends in obesity prevalence in recent years and to predict the obesity prevalence in 2015 in European populations.Methods
Data of 97 942 participants from seven cohorts involved in the European Prospective Investigation into Cancer and Nutrition (EPIC) study participating in the Diogenes project (named as “Diogenes cohort” in the following) with weight measurements at baseline and follow-up were used to predict future obesity prevalence with logistic linear and non-linear (leveling off) regression models. In addition, linear and leveling off models were fitted to the EPIC-Potsdam dataset with five weight measures during the observation period to find out which of these two models might provide the more realistic prediction.Results
During a mean follow-up period of 6 years, the obesity prevalence in the Diogenes cohort increased from 13% to 17%. The linear prediction model predicted an overall obesity prevalence of about 30% in 2015, whereas the leveling off model predicted a prevalence of about 20%. In the EPIC-Potsdam cohort, the shape of obesity trend favors a leveling off model among men (R2 = 0.98), and a linear model among women (R2 = 0.99).Conclusion
Our data show an increase in obesity prevalence since the 1990ies, and predictions by 2015 suggests a sizeable further increase in European populations. However, the estimates from the leveling off model were considerably lower. 相似文献105.
Elisabeth Schramm Moritz Elsaesser Carolin Jenkner Martin Hautzinger Sabine C. Herpertz 《World psychiatry》2024,23(2):257-266
Effect sizes of psychotherapies currently stagnate at a low-to-moderate level. Personalizing psychotherapy by algorithm-based modular procedures promises improved outcomes, greater flexibility, and a better fit between research and practice. However, evidence for the feasibility and efficacy of modular-based psychotherapy, using a personalized treatment algorithm, is lacking. This proof-of-concept randomized controlled trial was conducted in 70 adult outpatients with a primary DSM-5 diagnosis of major depressive disorder, a score higher than 18 on the 24-item Hamilton Rating Scale for Depression (HRSD-24), at least one comorbid psychiatric diagnosis according to the Structured Clinical Interview for DSM-5 (SCID-5), a history of at least “moderate to severe” childhood maltreatment on at least one domain of the Childhood Trauma Questionnaire (CTQ), and exceeding the cut-off value on at least one of three measures of early trauma-related transdiagnostic mechanisms: the Rejection Sensitivity Questionnaire (RSQ), the Interpersonal Reactivity Index (IRI), and the Difficulties in Emotion Regulation Scale-16 (DERS-16). Patients were randomized to 20 sessions of either standard cognitive-behavioral therapy alone (CBT) or CBT plus transdiagnostic modules according to a mechanism-based treatment algorithm (MoBa), over 16 weeks. We aimed to assess the feasibility of MoBa, and to compare MoBa vs. CBT with respect to participants’ and therapists’ overall satisfaction and ratings of therapeutic alliance (using the Working Alliance Inventory - Short Revised, WAI-SR), efficacy, impact on early trauma-related transdiagnostic mechanisms, and safety. The primary outcome for efficacy was the HRSD-24 score at post-treatment. Secondary outcomes included, among others, the rate of response (defined as a reduction of the HRSD-24 score by at least 50% from baseline and a score <16 at post-treatment), the rate of remission (defined as a HRSD-24 score ≤8 at post-treatment), and improvements in early trauma-related mechanisms of social threat response, hyperarousal, and social processes/empathy. We found no difficulties in the selection of the transdiagnostic modules in the individual patients, applying the above-mentioned cut-offs, and in the implementation of MoBa. Both participants and therapists reported higher overall satisfaction and had higher WAI-SR ratings with MoBa than CBT. Both approaches led to major reductions of depressive symptoms at post-treatment, with a non-significant superiority of MoBa over CBT. Patients randomized to MoBa were nearly three times as likely to experience remission at the end of therapy (29.4% vs. 11.4%; odds ratio, OR = 3.2, 95% CI: 0.9-11.6). Among mechanism-based outcomes, MoBa patients showed a significantly higher post-treatment effect on social processes/empathy (p<0.05) compared to CBT patients, who presented an exacerbation on this domain at post-treatment. Substantially less adverse events were reported for MoBa compared to CBT. These results suggest the feasibility and acceptability of an algorithm-based modular psychotherapy complementing CBT in depressed patients with psychiatric comorbidities and early trauma. While initial evidence of efficacy was observed, potential clinical advantages and interindividual heterogeneity in treatment outcomes will have to be investigated in fully powered confirmation trials. 相似文献
106.
Muntadher Al Zaidi Carmen Pizarro Carolin Bley Elena Repges Alexander Sedaghat Sebastian Zimmer Felix Jansen Vedat Tiyerili Georg Nickenig Dirk Skowasch Adem Aksoy 《Cell stress & chaperones》2022,27(5):561
Pulmonary arterial hypertension (PAH) is driven by vascular remodelling due to inflammation and cellular stress, including endoplasmic reticulum stress (ER stress). The main ER-stress chaperone, glucose-regulated protein 78 kDa (GRP78), is known to have protective effects in inflammatory diseases through extracellular signalling. The aim of this study is to investigate its significance in PAH. Human pulmonary arterial smooth muscle cells (PASMC) were stimulated with compounds that induce ER stress, after which the secretion of GRP78 into the cell medium was analysed by western blot. We found that when ER stress was induced in PASMC, there was also a time-dependent secretion of GRP78. Next, naïve PASMC were treated with conditioned medium (CM) from the ER-stressed donor PASMC. Incubation with CM from ER-stressed PASMC reduced the viability, oxidative stress, and expression of inflammatory and ER-stress markers in target cells. These effects were abrogated when the donor cells were co-treated with Brefeldin A to inhibit active secretion of GRP78. Direct treatment of PASMC with recombinant GRP78 modulated the expression of key inflammatory markers. Additionally, we measured GRP78 plasma levels in 19 PAH patients (Nice Group I) and correlated the levels to risk stratification according to ESC guidelines. Here, elevated plasma levels of GRP78 were associated with a favourable risk stratification. In conclusion, GRP78 is secreted by PASMC under ER stress and exhibits protective effects from the hallmarks of PAH in vitro. Circulating GRP78 may serve as biomarker for risk adjudication of patients with PAH.Graphical abstractProposed mechanism of ER-stress-induced GRP78 secretion by PASMC. Extracellular GRP78 can be measured as a circulating biomarker and is correlated with favourable clinical characteristics. Conditioned medium from ER-stressed PASMC reduces extensive viability, ROS formation, inflammation, and ER stress in target cells. These effects can be abolished by blocking protein secretion in donor cells by using Brefeldin A. Supplementary InformationThe online version contains supplementary material available at 10.1007/s12192-022-01292-y. 相似文献
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