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1.
The International Journal of Cardiovascular Imaging - Global longitudinal strain (GLS) has proven to be a powerful prognostic marker in various patient populations, but the prognostic value of...  相似文献   
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Reports on pediatric low-grade diffuse glioma WHO-grade II (DG2) suggest an impaired survival rate, but lack conclusive results for genetically defined DG2-entities. We analyzed the natural history, treatment and prognosis of DG2 and investigated which genetically defined sub-entities proved unfavorable for survival. Within the prospectively registered, population-based German/Swiss SIOP-LGG 2004 cohort 100 patients (age 0.8-17.8 years, 4% neurofibromatosis [NF1]) were diagnosed with a DG2. Following biopsy (41%) or variable extent of resection (59%), 65 patients received no adjuvant treatment. Radiologic progression or severe neurologic symptoms prompted chemotherapy (n = 18) or radiotherapy (n = 17). Multiple lines of salvage treatment were necessary for 19/35 patients. Five years event-free survival dropped to 0.44, while 5 years overall survival was 0.90 (median observation time 8.3 years). Extensive genetic profiling of 65/100 DG2 identified Histone3-K27M-mutation in 4, IDH1-mutation in 11, BRAF-V600-mutation in 12, KIAA1549-BRAF-fusions in 6 patients, while the remaining 32 tumor tissues did not show alterations of these genes. Progression to malignant glioma occurred in 12 cases of all genetically defined subgroups within a range of 0.5 to 10.8 years, except for tumors carrying KIAA1549-BRAF-fusions. Histone3-K27M-mutant tumors proved uniformly fatal within 0.6 to 2.4 years. The current LGG treatment strategy seems appropriate for all DG2-entities, with the exemption of Histone3-K27M-mutant tumors that require a HGG-related treatment strategy. Our data confirm the importance to genetically define pediatric low-grade diffuse gliomas for proper treatment decisions and risk assessment.  相似文献   
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Agri-environmental schemes (AES) aim to restore biodiversity and biodiversity-mediated ecosystem services in landscapes impoverished by modern agriculture. However, a systematic, empirical evaluation of different AES types across multiple taxa and functional groups is missing. Within one orthogonal design, we studied sown flowering AES types with different temporal continuity, size, and landscape context and used calcareous grasslands as seminatural reference habitat. We measured species richness of 12 taxonomic groups (vascular plants, cicadas, orthopterans, bees, butterflies, moths, hoverflies, flower visiting beetles, parasitoid wasps, carabid beetles, staphylinid beetles, and birds) representing 5 trophic levels. A total of 54,955 specimens were identified using traditional taxonomic methods, and bulk arthropod samples were identified through DNA metabarcoding, resulting in a total of 1,077 and 2,110 taxa, respectively. Species richness of most taxonomic groups, as well as multidiversity and richness of pollinators, increased with temporal continuity of AES types. Some groups responded to size and landscape context, but multidiversity and richness of pollinators and natural enemies were not affected. AES flowering fields supported different species assemblages than calcareous grasslands, but assemblages became more similar to those in seminatural grasslands with increasing temporal continuity. Our results indicate that AES flowering fields and seminatural grasslands function synergistically. Flowering fields support biodiversity even when they are relatively small and in landscapes with few remaining seminatural habitats. We therefore recommend a network of smaller, temporally continuous AES flowering fields of different ages, combined with permanent seminatural grasslands, to maximize benefits for biodiversity conservation and ecosystem service delivery in agricultural landscapes.

Human societies are facing a worldwide loss of biodiversity with alarming declines of insect diversity in temperate agricultural landscapes (1, 2). This loss of biodiversity is jeopardizing agricultural production as important ecosystem services ensuring crop yields are directly driven by biodiversity (3). Biodiversity, however, requires suitable habitats for species to persist, forage, nest, reproduce, and hibernate (4, 5). This challenge has been recognized and agri-environmental schemes (AES) have been introduced in the European Union and other regions to reverse biodiversity declines, to restore functional diversity, and to harness the benefits of ecosystem services, like pollination and pest control, in agricultural landscapes (68).An important component of AES to fulfill these goals is the establishing of habitats that provide limiting resources, such as food and shelter for a broad range of organisms. Typically, farmers are financially compensated on a per area basis, but the effectiveness of schemes is often unclear. Thus, compensations might not direct farmers’ decisions among different AES to the ecologically most meaningful ones (7). A variety of different habitats are created as AES, ranging from hedgerows to sown flower strips or flowering fields, with the latter being widely used due to their flexible applicability and public appreciation (4). Recent assessments, however, found that overall, European AES are not fulfilling their goals (6, 9). Particularly, the value of AES for securing biodiversity is under debate (10, 11). Beneficial effects previously reported focused on single taxonomic or trophic levels or ecosystem services and varied among study designs, taxa, or services assessed (1214). Conclusive multitaxa approaches assessing potential services and disservices in one design are missing (8). Furthermore, it is unclear how different properties of AES habitats (e.g., their temporal continuity or size) and varying landscape context affect biodiversity across multiple taxonomic groups.Temporal continuity is an important factor affecting biodiversity. Higher temporal continuity increases heterogeneity within a habitat and creates niches for more species (15, 16). Temporal continuity also enables weak dispersers and higher tropic levels to colonize a habitat, with the latter being dependent on established populations of lower trophic levels (15). In AES habitats, the influence and the effects of temporal continuity have so far been neglected. Newly established flowering fields were found to be more attractive to pollinators than older flowering fields, but pollination services in adjacent fields peak 2 y after initial sowing (14, 17). Older AES habitats could potentially also benefit rare and endangered species with specific habitat requirements, if species assemblages in AES habitats change toward those in permanent species-rich seminatural grasslands with time or increased temporal continuity (18).Apart from temporal continuity, size might be an important predictor for the conservation value of AES habitats. Increasing habitat size leads to an increased species richness as it is accompanied with the establishment of larger, more stable populations and allows higher trophic levels to persist (1921). It is unclear whether biodiversity in a landscape benefits more from few large habitats or a network of many small habitats (22, 23). Relationships between size and species richness might therefore be essential for the planning and strategic placement of AES habitats.Source habitats for biodiversity are needed in agricultural landscapes to build up local populations in newly established AES habitats from regional species pools (24). Seminatural habitats embedded in agricultural landscapes have been shown to support farmland diversity (25, 26), and thus AES habitats in complex landscapes with high proportions of seminatural habitats potentially host the highest diversity.Here, we investigate the effects of AES differing in temporal continuity, size, and surrounding landscape context over several years on multiple taxonomic groups within one study design. Different types of flowering fields are commonly established by farmers as part of AES to provide additional flower resources. These fields are sown with seed mixtures adapted to local soil properties and taken from regional species pools. After a certain timespan, often varying from 1 to 10 y, flowering fields are returned to crop production. The studied flowering fields differed in temporal continuity from: 1) Newly sown on arable land, over 2) refreshed (i.e., flower fields resown after 5 y) to 3) continuous, 6-y-old flowering fields. Species-rich calcareous grasslands were used as permanent control (Fig. 1 and Table 1). Calcareous grasslands are seminatural biodiversity hotspots in Europe and are preserved by low intensive mowing or grazing (27). We investigated species richness in these 4 AES types across 12 taxonomic groups belonging to 5 trophic levels, including pollinators (bees, butterflies, moths, flower visiting beetles, and hoverflies) and natural enemies (parasitoid wasps, carabid beetles, staphylinid beetles, and birds) as providers of important ecosystem services (3). Species were identified by classic taxonomic techniques (vascular plants, orthopterans, bees, butterflies, moths, flower visiting beetles, carabid beetles, staphylinid beetles, and birds) and DNA metabarcoding (cicadas, hoverflies, and parasitoid wasps). Repeated recordings of a subset of four taxonomic groups (plants, orthopterans, bees, and carabid beetles) within 2 y were performed to clarify whether short-term succession changed assemblages in newly established flowering fields toward those in seminatural calcareous grasslands. Apart from analyses for each taxonomic group, we performed a multidiversity analysis by calculating a diversity index across all taxa, pollinators, and natural enemies (28). Our study aims to judge which types of AES fulfill the goal of restoring biodiversity and ecosystem services in agricultural landscapes best, and should therefore be fostered. Such data are urgently needed to build the scientific basis for a successful transition of European Union and global policies to biodiversity-friendly and sustainable crop production.Open in a separate windowFig. 1.Study design on the landscape and site level. Biodiversity across 12 different taxonomic levels (from top to bottom: Vascular plants, orthopterans, cicadas, bees, butterflies, moths, flower visiting beetles, hoverflies, parasitoid wasps, carabid beetles, staphylinid beetles, birds) was recorded using a variety of classic methods (pan traps, pitfall traps, transect walks, light traps combined with taxonomic identification) as well as metabarcoding analyses (using samples collected with Malaise traps). The different types of flowering fields and calcareous grasslands were located along a gradient of temporal continuity (Table 1). All AES types covered independent gradients of seminatural habitat in the surrounding landscape and habitat size (purple, AES; yellow, arable land; light green, seminatural habitat; dark green, forest; gray, urban). Repeated recordings over 2 y were performed for vascular plants, orthopterans, bees, and carabid beetles to assess whether succession shifted assemblages in flowering fields toward those in seminatural calcareous grasslands.Table 1.Differences in temporal continuity
Habitat age, yLast soil disturbance, yTemporal continuityPrevious land useManagementVegetation
New sown flowering field11LowArable landNoneCustomary flower seed mixture; sown in the previous year
Refreshed sown flowering field>61Low–intermediateSown flowering field (5 y)NoneCustomary flower seed mixture; sown in the previous year
Continuous sown flowering field>6>6Intermediate–highSown flowering field (5 y)Mulching above ground once per year after JuneCustomary flower seed mixture sown >6 y ago; strongly shaped by succession
Calcareous grassland>>20>>20HighNAGrazing or mowing once per year after JuneSeminatural xerothermic grassland vegetation
Open in a separate windowDifferences in temporal continuity—resulting from habitat age and management—of the studied AES types in 2016 (first year of the study).We expected that: 1) Benefits of temporal habitat continuity differ among taxonomic groups, pollinators, and natural enemies; 2) temporal continuity and short-term succession alter species assemblages of sown flowering fields toward those in seminatural grasslands; and 3) multidiversity in sown flowering fields benefits most from the combination of temporal continuity, large habitat size, and high proportion of seminatural habitats in the landscape.  相似文献   
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Despite the high probability of cure of patients with acute promyelocytic leukemia (APL), mechanisms of relapse are still largely unclear. Mutational profiling at diagnosis and/or relapse may help to identify APL patients needing frequent molecular monitoring and early treatment intervention. Using an NGS approach including a 31 myeloid gene-panel, we tested BM samples of 44 APLs at the time of diagnosis, and of 31 at relapse. Mutations in PML and RARA genes were studied using a customized-NGS-RNA panel. Patients relapsing after ATRA-chemotherapy rarely had additional mutations (P = .009). In patients relapsing after ATRA/ATO, the PML gene was a preferential mutation target. We then evaluated the predictive value of mutations at APL diagnosis. A median of two mutations was detectable in 9/11 patients who later relapsed, vs one mutation in 21/33 patients who remained in CCR (P = .0032). This corresponded to a significantly lower risk of relapse in patients with one or less mutations (HR 0.046; 95% CI 0.011-0.197; P < .0001). NGS-analysis at the time of APL diagnosis may inform treatment decisions, including alternative treatments for cases with an unfavorable mutation profile.  相似文献   
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1. The utility of 1-aminobenzotriazole (ABT), incorporated in food, has been investigated as an approach for longer term inhibition of cytochrome P450 (P450) enzymes in mice.

2. In rats, ABT inhibits gastric emptying, to investigate this potential limitation in mice we examined the effect of ABT administration on the oral absorption of NVS-CRF38. Two hour prior oral treatment with 100?mg/kg ABT inhibited the oral absorption of NVS-CRF38, Tmax was 4?hours for ABT-treated mice compared to 0.5?hours in the control group.

3. A marked inhibition of hepatic P450 activity was observed in mice fed with ABT containing food pellets for 1?month. P450 activity, as measured by the oral clearance of antipyrine, was inhibited on day 3 (88% of control), week 2 (83% of control) and week 4 (80% of control).

4. Tmax values for antipyrine were comparable between ABT-treated mice and the control group, alleviating concerns about impaired gastric function.

5. Inclusion of ABT in food provides a minimally invasive and convenient approach to achieve longer term inhibition of P450 activity in mice. This model has the potential to enable pharmacological proof-of-concept studies for research compounds which are extensively metabolised by P450 enzymes.  相似文献   

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Glaucoma is the second leading cause of blindness worldwide. The purpose of this paper is to give a review on the epidemiology of the disease, on the importance and the consequences of glaucoma for people regarding their daily life, their ability to work, and quality of life.  相似文献   
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The incidence of drug-induced structural cardiotoxicity, which may lead to heart failure, has been recognized in association with the use of anthracycline anti-cancer drugs for many years, but has also been shown to occur following treatment with the new generation of targeted anti-cancer agents that inhibit one or more receptor or non-receptor tyrosine kinases, serine/threonine kinases as well as several classes of non-oncology agents. A workshop organized by the Medical Research Council Centre for Drug Safety Science (University of Liverpool) on 5 September 2013 and attended by industry, academia and regulatory representatives, was designed to gain a better understanding of the gaps in the field of structural cardiotoxicity that can be addressed through collaborative efforts. Specific recommendations from the workshop for future collaborative activities included: greater efforts to identify predictive (i) preclinical; and (ii) clinical biomarkers of early cardiovascular injury; (iii) improved understanding of comparative physiology/pathophysiology and the clinical predictivity of current preclinical in vivo models; (iv) the identification and use of a set of cardiotoxic reference compounds for comparative profiling in improved animal and human cellular models; (v) more sharing of data (through publication/consortia arrangements) on target-related toxicities; (vi) strategies to develop cardio-protective agents; and (vii) closer interactions between preclinical scientists and clinicians to help ensure best translational efforts.  相似文献   
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