45 research outputs found

    Terdiurnal signatures in midlatitude sporadic E layers occurrence rates

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    Global Positioning System radio occultation measurements by the FORMOsa SATellite mission-3/Constellation Observing System for Meteorology, Ionosphere and Climate satellites were used to analyse the behaviour of the signature of the terdiurnal tide in sporadic E (ES) layers at midlatitudes (43°N – 63°N). According to theory, the occurrence of ES is expected when the vertical zonal wind shear, which is mainly owing to solar tides, is negative. 4-year means, based on 3-monthly running mean zonal means from December 2006 - November 2010, were constructed for the terdiurnal oscillation in the occurrence frequency of ES. Comparison of the results with VHF meteor radar observations of the terdiurnal tide and the 8-hr oscillation in the vertical zonal wind shear at Collm, Germany (51.3°N, 13°E) shows a clear correspondence between the 8-hr Es and wind shear signature.Radiookultationsmessungen auf der Basis von GPS-Messungen der FORMOsa SATellite mission-3/Constellation Observing System for Meteorology, Ionosphere and Climate-Satelliten wurden verwendet, um die Signatur der 8-stündigen Gezeiten in den Auftrittsraten von sporadischen E (Es)-Schichten zu analysieren. Nach der allgemein anerkannten Windscherungstheorie treten Es-Schichten im Bereich negativer vertikaler Windscherung auf, welche in der unteren Thermosphäre hauptsächlich durch solare Gezeiten hervorgerufen werden. Speziell werden hier 4-jährige Mittelwerte saisonal gemittelter Auftrittsraten untersucht um die 8-stündige Signatur zu finden. Ein Vergleich mit Radarmessungen des Windes über Collm zeigt, dass die saisonale und tägliche Variabilität der 8-stündigen Komponente der Es-Raten sehr gut mit derjenigen der gemessenen Windscherung übereinstimmt

    Enhanced sporadic E occurrence rates during the Geminid meteor showers 2006-2010

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    Sporadic E (Es) layer occurrence rates derived from GPS radio occultation measurements during the Geminid meteor showers 2006-2010 are compared with meteor rates obtained with the Collm VHF meteor radar. In most years, Es rates increase after the shower, with a short delay of few days. This indicates a possible link between meteor influx and the production of metallic ions that may form Es. However, the correlation between Es rates and meteor flux varies from year to year, indicating that more processes significantly influence Es occurrence also during meteor showers

    Communication and signal exchange in the Rhizobium bradyrhizobium legume system

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    A new comprehensive communication concept in the Rhizobium/Bradyrhizobium legume symbiosis was developed. It includes a root zone specific flavonoid exudation, the differential activity of phenylpropane/acetate pathway derivatives on chemotaxis, nod-gene inducing activity and phytoalexin resistance induction on the microsymbiont side (Bradyrhizobium). Nod factor production from the microsymbiont affects the host plant in root hair curling and meristem induction. Phytoalexin production in the host plant is also an early response, however repressed to a low level after a few hours. Another strategy of the microsymbiont to overcome phytoalexin effects is degradation of phytoalexins in Rhizobium leguminosarum bv. vicieae. Competitiveness within the same infection group of the microsymbiont was studied with gus-gene fusion, using the blue coloured nodules to easily discriminate marked strains from unmarked competitors. New exopolysaccharide (EPS) mutants of Bradyrhizobium japonicum were reconstructed homologous with a DNA region to exoB gene of Rhizobium meliloti. Their clearly reduced competitiveness of nodulation, demonstrates that exopolysaccharides of Bradyrhizohium japonicum also have an important function during the early stages of this symbiotic interaction

    Palate Lung Nasal Clone (PLUNC), a Novel Protein of the Tear Film: Three-Dimensional Structure, Immune Activation, and Involvement in Dry Eye Disease (DED)

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    Citation: Schicht M, Rausch F, Beron M, et al. Palate lung nasal clone (PLUNC), a novel protein of the tear film: three-dimensional structure, immune activation, and involvement in dry eye disease (DED). Invest Ophthalmol Vis Sci. 2015;56:7312-7323. DOI:10.1167/iovs.15-17560 PURPOSE. Palate Lung Nasal Clone (PLUNC) is a hydrophobic protein belonging to the family of surfactant proteins that is involved in fluid balance regulation of the lung. Moreover, it is known to directly act against gram-negative bacteria. The purpose of this study was to investigate the possible expression and antimicrobial role of PLUNC at the healthy ocular surface and in tears of patients suffering from dry eye disease (DED). METHODS. Bioinformatics and biochemical and immunologic methods were combined to elucidate the structure and function of PLUNC at the ocular surface. Tissue-specific localization was performed by using immunohistochemistry. The PLUNC levels in tear samples from non-Sjögren's DED patients with moderate dry eye suffering either from hyperevaporation or tear deficiency were analyzed by ELISA and compared with tears from healthy volunteers. RESULTS. Palate Lung Nasal Clone is expressed under healthy conditions at the ocular surface and secreted into the tear film. Protein modeling studies and molecular dynamics simulations performed indicated surface activity of PLUNC. In vitro experiments revealed that proinflammatory cytokines and bacterial supernatants have only a slight effect on the expression of PLUNC in HCE and HCjE cell lines. In tears from DED patients, the PLUNC concentration is significantly increased (7-fold in evaporative dry eye tears and 17-fold in tears from patients with tear deficiency) compared with healthy subjects. CONCLUSIONS. The results show that PLUNC is a protein of the tear film and suggest that it plays a role in fluid balance and surface tension regulation at the ocular surface

    Establishing a Mental Health Surveillance in Germany: Development of a framework concept and indicator set

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    In the course of the recognition of mental health as an essential component of population health, the Robert Koch Institute has begun developing a Mental Health Surveillance (MHS) system for Germany. MHS aims to continuously report data for relevant mental health indicators, thus creating a basis for evidence-based planning and evaluation of public health measures. In order to develop a set of indicators for the adult population, potential indicators were identified through a systematic literature review and selected in a consensus process by international and national experts and stakeholders. The final set comprises 60 indicators which, together, represent a multidimensional public health framework for mental health across four fields of action. For the fifth field of action ‘Mental health promotion and prevention’ indicators still need to be developed. The methodology piloted proved to be practicable. Strengths and limitations will be discussed regarding the search and definition of indicators, the scope of the indicator set as well as the participatory decision-making process. Next steps in setting up the MHS will be the operationalisation of the single indicators and their extension to also cover children and adolescents. Given assured data availability, the MHS will contribute to broadening our knowledge on population mental health, supporting a targeted promotion of mental health and reducing the disease burden in persons with mental disorders

    Corneal Limbal Microenvironment Can Induce Transdifferentiation of Hair Follicle Stem Cells into Corneal Epithelial-like Cells

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    The aim of this study was to investigate the transdifferentiation potential of murine vibrissa hair follicle (HF) stem cells into corneal epithelial-like cells through modulation by corneal- or limbus-specific microenvironmental factors. Adult epithelial stem cells were isolated from the HF bulge region by mechanical dissection or fluorescence-activated cell sorting using antibodies to α6 integrin, enriched by clonal expansion, and subcultivated on various extracellular matrices (type IV collagen, laminin-1, laminin-5, fibronectin) and in different conditioned media derived from central and peripheral corneal fibroblasts, limbal stromal fibroblasts, and 3T3 fibroblasts. Cellular phenotype and differentiation were evaluated by light and electron microscopy, real-time reverse transcription-polymerase chain reaction, immunocytochemistry, and Western blotting, using antibodies against putative stem cell markers (K15, α6 integrin) and differentiation markers characteristic for corneal epithelium (K12, Pax6) or epidermis (K10). Using laminin-5, a major component of the corneo-limbal basement membrane zone, and conditioned medium from limbal stromal fibroblasts, clonally enriched HF stem and progenitor cells adhered rapidly and formed regularly arranged stratified cell sheets. Conditioned medium derived from limbal fibroblasts markedly upregulated expression of cornea-specific K12 and Pax6 on the mRNA and protein level, whereas expression of the epidermal keratinocyte marker K10 was strongly downregulated. These findings suggest that adult HF epithelial stem cells are capable of differentiating into corneal epithelial-like cells in vitro when exposed to a limbus-specific microenvironment. Therefore, the HF may be an easily accessible alternative therapeutic source of autologous adult stem cells for replacement of the corneal epithelium and restoration of visual function in patients with ocular surface disorders

    Prostaglandin E2 Synthesizing Enzymes in Rheumatoid Arthritis B Cells and the Effects of B Cell Depleting Therapy on Enzyme Expression

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    Introduction: B cells may play an important role in promoting immune activation in the rheumatoid synovium and can produce prostaglandin E-2 (PGE(2)) when activated. In its turn, PGE(2) formed by cyclooxygenase (COX) and microsomal prostaglandin E-2 synthase 1 (MPGES1) contributes to the rheumatoid arthritis (RA) pathological process. Therapeutic depletion of B cells results in important improvement in controlling disease activity in rheumatoid patients. Therefore we investigated the expression of PGE(2) pathway enzymes in RA B cells and evaluated the effects of B cell depleting therapy on their expression in RA tissue. Methods: B cells expressing MPGES1 and COX-2 were identified by flow cytometry in in vitro stimulated and control mononuclear cells isolated from synovial fluid and peripheral blood of RA patients. Synovial biopsies were obtained from 24 RA patients before and at two consecutive time points after rituximab therapy. Expression of MPGES1, COX-1 and COX-2, as well as interleukin (IL)-1 beta and IL-6, known inducers of MPGES1, was quantified in immunostained biopsy sections using computerized image analysis. Results: Expression of MPGES1 or COX-2 was significantly upregulated upon stimulation of B cells from blood and synovial fluid while control cells displayed no detectable enzymes. In synovial biopsy sections, the expression of MPGES1, COX-1 or COX-2 was resistant to rituximab therapy at 8 or 16 weeks after start of treatment. Furthermore expression of IL-1 beta in the synovial tissue remained unchanged, while IL-6 tended to decrease after therapy. Conclusions: Therapy with B cell depleting agents, although efficient in achieving good clinical and radiographic response in RA patients, leaves important inflammatory pathways in the rheumatoid synovium essentially unaffecte

    Assessing the costs and cost-effectiveness of ICare internet-based interventions (protocol)

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    Background: Mental health problems are common and place a burden on the individual as well as on societal resources. Despite the existence of evidence-based treatments, access to treatment is often prevented or delayed due to insufficient health care resources. Effective internet-based self-help interventions have the potential to reduce the risk for mental health problems, to successfully bridge waiting time for face-to-face treatment and to address inequities in access. However, little is known about the cost-effectiveness of such interventions. This paper describes the study protocol for the economic evaluation of the studies that form the ICare programme of internet-based interventions for the prevention and treatment of a range of mental health problems. Methods: An overarching work package within the ICare programme was developed to assess the cost-effectiveness of the internet-based interventions alongside the clinical trials. There are two underlying tasks in the ICare economic evaluation. First, to develop schedules that generate equivalent and comparable information on use of services and supports across seven countries taking part in clinical trials of different interventions and second, to estimate unit costs for each service and support used. From these data the cost per person will be estimated by multiplying each participant's use of each service by the unit cost for that service, taking both a public sector and a societal perspective. This individual level of cost data matches the level of outcome data used in the clinical trials. Following the analyses of service use and costs data, joint analysis of costs and outcomes will be undertaken to provide findings on the relative cost-effectiveness of the interventions. These analyses use a well-established framework, the Production of Welfare approach, and standard methods and techniques underpinned by economic theory. Discussion/conclusion: Existing research tends to support the effectiveness of internet-based interventions, but there is little information on their cost-effectiveness compared to ‘treatment as usual’. The economic evaluation of ICare interventions will add considerably to this evidence base

    Gene expression analysis of cell death induction by Taurolidine in different malignant cell lines

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    <p>Abstract</p> <p>Background</p> <p>The anti-infective agent Taurolidine (TRD) has been shown to have cell death inducing properties, but the mechanism of its action is largely unknown. The aim of this study was to identify potential common target genes modulated at the transcriptional level following TRD treatment in tumour cell lines originating from different cancer types.</p> <p>Methods</p> <p>Five different malignant cell lines (HT29, Chang Liver, HT1080, AsPC-1 and BxPC-3) were incubated with TRD (100 μM, 250 μM and 1000 μM). Proliferation after 8 h and cell viability after 24 h were analyzed by BrdU assay and FACS analysis, respectively. Gene expression analyses were carried out using the <it>Agilent </it>-microarray platform to indentify genes which displayed conjoint regulation following the addition of TRD in all cell lines. Candidate genes were subjected to <it>Ingenuity Pathways Analysis </it>and selected genes were validated by qRT-PCR and Western Blot.</p> <p>Results</p> <p>TRD 250 μM caused a significant inhibition of proliferation as well as apoptotic cell death in all cell lines. Among cell death associated genes with the strongest regulation in gene expression, we identified pro-apoptotic transcription factors (EGR1, ATF3) as well as genes involved in the ER stress response (PPP1R15A), in ubiquitination (TRAF6) and mitochondrial apoptotic pathways (PMAIP1).</p> <p>Conclusions</p> <p>This is the first conjoint analysis of potential target genes of TRD which was performed simultaneously in different malignant cell lines. The results indicate that TRD might be involved in different signal transduction pathways leading to apoptosis.</p

    Aufbau einer Mental Health Surveillance in Deutschland: Entwicklung von Rahmenkonzept und Indikatorenset

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    Im Zuge der Anerkennung psychischer Gesundheit als wesentlicher Bestandteil der Bevölkerungsgesundheit wird am Robert Koch-Institut eine Mental Health Surveillance (MHS) für Deutschland aufgebaut. Ziel der MHS ist die kontinuierliche Berichterstattung relevanter Kennwerte zum Zweck einer evidenzbasierten Planung und Evaluation von Public-Health- Maßnahmen. Zur Entwicklung eines Indikatorensets für die erwachsene Bevölkerung wurden potenzielle Indikatoren durch eine systematische Literaturrecherche identifiziert und in einem strukturierten Konsentierungsprozess durch internationale und nationale Expertinnen und Experten beziehungsweise Stakeholder ausgewählt. Das finale Set enthält 60 Indikatoren, die ein mehrdimensionales Public-Health-Rahmenkonzept psychischer Gesundheit in vier Handlungsfeldern abbilden. Im fünften Handlungsfeld „Gesundheitsförderung und Prävention“ besteht Bedarf der Indikatorenentwicklung. Die pilotierte Methodik erwies sich als praktikabel. Diskutiert werden Stärken und Limitationen der Recherche und Definition von Indikatoren, der Umfang des Indikatorensets sowie die partizipative Entscheidungsfindung. Nächste Schritte zur Etablierung der MHS bestehen in der Operationalisierung von Indikatoren und der Erweiterung unter anderem auf das Kindes- und Jugendalter. Bei gesicherter Datenverfügbarkeit wird die MHS zum Wissen über die Gesundheit der Bevölkerung beitragen und die gezielte Förderung psychischer Gesundheit sowie die Verringerung der Krankheitslast psychischer Störungen unterstützen
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