Wpływy Helicobacter pylori poza przewodem pokarmowym

Związek przyczynowo-skutkowy zakażenia Helicobacter pylori (H. pylori) z rozwojem wielu chorób przewodu pokarmowego nie ulega dziś wątpliwości. Szerokie zainteresowanie badaczy budzą natomiast związki tego zakażenia ze schorzeniami spoza przewodu pokarmowego. Schorzeniami, w których związki te uznać można za wystarczająco silne, aby dokonać racjonalnej próby eradykacji zakażenia, są niedokrwistość z niedoboru żelaza, immunologiczna plamica małopłytkowa, niedobór witaminy B12. Zasadne wydaje się to także w trądziku różowatym oraz pokrzywce przewlekłej. Inne związki nieco szerzej omówione w artykule, jak choroba wieńcowa, udar niedokrwienny, choroby Parkinsona i Alzheimera, zespół metaboliczny, cukrzyca typu 2 czy fibromialgia wydają się, jak na razie, raczej w sferze domniemań i badań i eradykacja nie ma w nich racjonalnego uzasadnienia. Stosowaniu eradykacji w przypadku mało udokumentowanych związków zakażenia H. pylori z chorobami poza przewodem pokarmowym może doprowadzić do dramatycznego spadku skuteczności antybiotyków w innych znacznie niebezpieczniejszych zakażeniach (pneumokoki, meningokoki, pałeczki jelitowe itp.) na skutek wzrostu lekooporności bakterii

Trudności i odrębności postępowania diagnostyczno-leczniczego w nieswoistych chorobach zapalnych jelit u dzieci

Nieswosite choroby zapalne jelit (NChZJ) to narastający problem w pediatrii. U dzieci częściej niż u dorosłych obserwuje się aktywną postać choroby Leśniowskiego-Crohna (ChLC) i częściej konieczna jest immunosupresja. U 39% dzieci po 2 latach wzrasta rozległość zmian zapalnych, a u 24% po 4 latach pojawiają się zwężenia lub powikłania penetracyjne. U dzieci dominuje fenotyp panenteralny (43% v. 3%), rzadsze jest izolowane zajęcie ileum (2% v. 31%) i jelita grubego (15% v. 36%). We wrzodziejącym zapaleniu jelita grubego (WZJG) w chwili rozpoznania rozległość zmian jest większa u dzieci niż u dorosłych (82% v. 48%). U 46% obserwuje się progresję w kierunku pancolitis. Początek WZJG w dzieciństwie znacznie zwiększa ryzyko kolektomii. Zapalenie jelita grubego w dzieciństwie (0−19 lat) zwiększa ryzyko względne raka jelita grubego do prawie 44 razy. 80% dzieci z ChLC ma niedobory masy ciała i wzrostu, 75% dziewcząt ma menarche dopiero w 16. rż. lub później, częściej wystepują opóźnienie wieku szkieletowego i osteoporoza. Trudności diagnostyczne NChZJ u dzieci wynikają z ograniczeń w wykonywaniu rezonansu magnetycznego < 4. rż., ograniczeń w endoskopii kapsułkowej i enteroskopii dwubalonowej. Częściej u dzieci niejednoznaczna bywa histopatologia. U dzieci w indukcji remisji w ChLC szeroko stosuje się żywienie enteralne równoważne z kortykoterapią, a zdecydowanie bezpieczniejsze. U dzieci terapie standardowe są często mało skuteczne, dostęp do terapii biologicznych ograniczony, a steroidozależność w okresie rozwojowym czyni nieodwracalne spustoszenia. Pomimo różnic NChZJ u dzieci i dorosłych to te same choroby, choć ich dynamika i konsekwencje mogą się nieco różnić

Adjusting risk-taking to the annual cycle of long-distance migratory birds

International audienceLife-history theory predicts that current behaviour affects future reproduction, implying that animals should optimise their escape strategies to reflect fitness costs and benefits of premature escape. Both costs and benefits of escape may change temporally with important consequences for the evolution of escape strategies. Moreover, escape strategies of species may differ according to their positions on slow-fast pace of life gradients. We studied risk-taking in long-distance migratory animals, waders (Charadriiformes), during the annual cycle, i.e., breeding in Europe, stopover in the Middle East and wintering in tropical Africa. Phylogenetically informed comparative analyses revealed that risk-taking (measured as flight initiation distance, FID) changed significantly over the year, being lowest during breeding and peaking at stopover sites. Similarly, relationships between risk-taking and life-history traits changed among stages of the annual cycle. While risk-taking significantly decreased with increasing body mass during breeding, risk-taking-body mass relationship became marginally significant in winter and disappeared during migration. The positive trend of risk-taking along slow-fast pace of life gradient measured as adult survival was only found during breeding. The season-dependent relationships between risk-taking and life history traits suggest that migrating animals respond to fluctuating environments by adopting behavioural plasticity

Seiberg-Witten theory and matrix models

We derive a family of matrix models which encode solutions to the Seiberg-Witten theory in 4 and 5 dimensions. Partition functions of these matrix models are equal to the corresponding Nekrasov partition functions, and their spectral curves are the Seiberg-Witten curves of the corresponding theories. In consequence of the geometric engineering, the 5-dimensional case provides a novel matrix model formulation of the topological string theory on a wide class of non-compact toric Calabi-Yau manifolds. This approach also unifies and generalizes other matrix models, such as the Eguchi-Yang matrix model, matrix models for bundles over $P^1$, and Chern-Simons matrix models for lens spaces, which arise as various limits of our general result.Comment: 43 pages, 5 figures; typos corrected, references added, derivation of the curve in section 4.2 corrected; published versio

Impact of landscape configuration and composition on pollinator communities across different European biogeographic regions

IntroductionHeterogeneity in composition and spatial configuration of landscape elements support diversity and abundance of flower-visiting insects, but this is likely dependent on taxonomic group, spatial scale, weather and climatic conditions, and is particularly impacted by agricultural intensification. Here, we analyzed the impacts of both aspects of landscape heterogeneity and the role of climatic and weather conditions on pollinating insect communities in two economically important mass-flowering crops across Europe. MethodsUsing a standardized approach, we collected data on the abundance of five insect groups (honey bees, bumble bees, other bees, hover flies and butterflies) in eight oilseed rape and eight apple orchard sites (in crops and adjacent crop margins), across eight European countries (128 sites in total) encompassing four biogeographic regions, and quantified habitat heterogeneity by calculating relevant landscape metrics for composition (proportion and diversity of land-use types) and configuration (the aggregation and isolation of land-use patches). ResultsWe found that flower-visiting insects responded to landscape and climate parameters in taxon- and crop-specific ways. For example, landscape diversity was positively correlated with honey bee and solitary bee abundance in oilseed rape fields, and hover fly abundance in apple orchards. In apple sites, the total abundance of all pollinators, and particularly bumble bees and solitary bees, decreased with an increasing proportion of orchards in the surrounding landscape. In oilseed rape sites, less-intensively managed habitats (i.e., woodland, grassland, meadows, and hedgerows) positively influenced all pollinators, particularly bumble bees and butterflies. Additionally, our data showed that daily and annual temperature, as well as annual precipitation and precipitation seasonality, affects the abundance of flower-visiting insects, although, again, these impacts appeared to be taxon- or crop-specific. DiscussionThus, in the context of global change, our findings emphasize the importance of understanding the role of taxon-specific responses to both changes in land use and climate, to ensure continued delivery of pollination services to pollinator-dependent crops

Serotype-Specific Pneumococcal Status prior to PCV 13 Administration in Children and Adolescents with Inflammatory Bowel Disease

The aim of this study was to evaluate the serotype-specific pneumococcal status of children and adolescents with inflammatory bowel disease (IBD) who were naïve to pneumococcal vaccination before administering the 13-valent pneumococcal conjugate vaccine (PCV 13). This was an open, prospective study on children and adolescents aged 5–18 years who had IBD and were naïve to pneumococcal vac­cination. A single dose of PCV 13 was administered to each patient. The geometric mean concentrations (GMCs) were measured for all 13 serotypes. A total of 122 subjects completed the study. Prevaccination GMCs ranged from 0.55 μg/ml (serotype 4) to 4.26 μg/ml (sero­type 19A). Prior to the administration of PCV 13, high GMCs were detected in older children and adolescents who had IBD and were naïve to pneumococcal vaccination

Transforming European Water Governance? Participation and River Basin Management under the EU Water Framework Directive in 13 Member States

The European Union (EU) Water Framework Directive (WFD) requires EU member states to produce and implement river basin management plans, which are to be designed and updated via participatory processes that inform, consult with, and actively involve all interested stakeholders. The assumption of the European Commission is that stakeholder participation, and institutional adaptation and procedural innovation to facilitate it, are essential to the effectiveness of river basin planning and, ultimately, the environmental impact of the Directive. We analyzed official documents and the WFD literature to compare implementation of the Directive in EU member states in the initial WFD planning phase (2000–2009). Examining the development of participatory approaches to river basin management planning, we consider the extent of transformation in EU water governance over the period. Employing a mixed quantitative and qualitative approach, we map the implementation “trajectories” of 13 member states, and then provide a detailed examination of shifts in river basin planning and participation in four member states (Germany, Sweden, Poland and France) to illustrate the diversity of institutional approaches observed. We identify a general tendency towards increased, yet circumscribed, stakeholder participation in river basin management in the member states examined, alongside clear continuities in terms of their respective pre-WFD institutional and procedural arrangements. Overall, the WFD has driven a highly uneven shift to river basin-level planning among the member states, and instigated a range of efforts to institutionalize stakeholder involvement—often through the establishment of advisory groups to bring organized stakeholders into the planning process

Genomic Characterization of Cholangiocarcinoma in Primary Sclerosing Cholangitis Reveals Therapeutic Opportunities

Background and Aims Lifetime risk of biliary tract cancer (BTC) in primary sclerosing cholangitis (PSC) may exceed 20%, and BTC is currently the leading cause of death in patients with PSC. To open new avenues for management, we aimed to delineate clinically relevant genomic and pathological features of a large panel of PSC-associated BTC (PSC-BTC). Approach and Results We analyzed formalin-fixed, paraffin-embedded tumor tissue from 186 patients with PSC-BTC from 11 centers in eight countries with all anatomical locations included. We performed tumor DNA sequencing at 42 clinically relevant genetic loci to detect mutations, translocations, and copy number variations, along with histomorphological and immunohistochemical characterization. Regardless of the anatomical localization, PSC-BTC exhibited a uniform molecular and histological characteristic similar to extrahepatic cholangiocarcinoma. We detected a high frequency of genomic alterations typical of extrahepatic cholangiocarcinoma, such asTP53(35.5%),KRAS(28.0%),CDKN2A(14.5%), andSMAD4(11.3%), as well as potentially druggable mutations (e.g.,HER2/ERBB2). We found a high frequency of nontypical/nonductal histomorphological subtypes (55.2%) and of the usually rare BTC precursor lesion, intraductal papillary neoplasia (18.3%). Conclusions Genomic alterations in PSC-BTC include a significant number of putative actionable therapeutic targets. Notably, PSC-BTC shows a distinct extrahepatic morpho-molecular phenotype, independent of the anatomical location of the tumor. These findings advance our understanding of PSC-associated cholangiocarcinogenesis and provide strong incentives for clinical trials to test genome-based personalized treatment strategies in PSC-BTC.Peer reviewe

The Herschel-Heterodyne Instrument for the Far-Infrared (HIFI): instrument and pre-launch testing

This paper describes the Heterodyne Instrument for the Far-Infrared (HIFI), to be launched onboard of ESA's Herschel Space Observatory, by 2008. It includes the first results from the instrument level tests. The instrument is designed to be electronically tuneable over a wide and continuous frequency range in the Far Infrared, with velocity resolutions better than 0.1 km/s with a high sensitivity. This will enable detailed investigations of a wide variety of astronomical sources, ranging from solar system objects, star formation regions to nuclei of galaxies. The instrument comprises 5 frequency bands covering 480-1150 GHz with SIS mixers and a sixth dual frequency band, for the 1410-1910 GHz range, with Hot Electron Bolometer Mixers (HEB). The Local Oscillator (LO) subsystem consists of a dedicated Ka-band synthesizer followed by 7 times 2 chains of frequency multipliers, 2 chains for each frequency band. A pair of Auto-Correlators and a pair of Acousto-Optic spectrometers process the two IF signals from the dual-polarization front-ends to provide instantaneous frequency coverage of 4 GHz, with a set of resolutions (140 kHz to 1 MHz), better than < 0.1 km/s. After a successful qualification program, the flight instrument was delivered and entered the testing phase at satellite level. We will also report on the pre-flight test and calibration results together with the expected in-flight performance