96 research outputs found

    Synergistic interaction of rickettsia and entomopathogenic nematodes in larvae of the cockchafer (Melolontha hippocastani)

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    Am Zoologischen Institut der Uni Heidelberg wurde bereits seit einigen Jahren an der Entwicklung einer biologischen Bekämpfungsstrategie gegen Maikäfer gearbeitet. Neben einem Bacillus thuringiensis-Stamm, der bei einigen Maikäfer-Verwandten wirksam ist (WAGNER & SCHNETTER 2001), wurde vor allem mit entomopathogenen Nematoden der Gattungen Steinernema und Heterorhabditis geforscht (BERNER & SCHNETTER 2001). Die Anfälligkeit der Larven sowohl des Feld- als auch des Waldmaikäfers gegenüber diesen Nematoden ist jedoch im Vergleich zu anderen Scarabaeiden, wie dem Gartenlaubkäfer (Phylloperta horticola), relativ gering (SULISTYANTO & EHLERS 1996), so dass auch die bisher durchgeführten Freilandversuche wenig Erfolg brachten (BERNER & SCHNETTER 2002). Neben der Suche nach möglichst infektiösen Nematodenarten und -stämmen ist für den Erfolg einer Nematodenapplikation im Freiland eine vorausgehende Systemanalyse des Standortes von entscheidender Bedeutung. Hierbei sind neben abiotischen Faktoren wie der Witterung und den Bodenverhältnissen auch biotische Faktoren wie dem Vorkommen von Pathogenen in der Engerling-Population zu erfassen. Insbesondere eine Vorinfektion der Engerling-Population kann einen falschen Wirkungsgrad der Nematoden vortäuschen, da unter diesen Bedingungen antagonistische oder synergistische Wechselwirkungen zwischen den latenten Pathogenen und den applizierten Nematoden zu erwarten sind. Ausgangspunkt der hier vorgestellten Arbeit war eine Engerling-Population des Waldmaikäfers (Melolontha hippocastani), die 1999 in der Nähe von Lorsch gefunden wurde und einen hohen Prozentsatz an Engerlingen aufwies, der mit Rickettsien (Rickettsiella popilliae) infiziert war. Aufgrund der hohen Dichte und der ausgeprägten Symptome der als „Lorscher Seuche“ bei Engerlingen bekannten Rickettsien-Infektion konnte die Krankheit bereits im Feld diagnostiziert werden (vgl. NIKLAS 1960).The work presented here investigates the efficiency of the entomopatogenic nematode Heterorhabditis bacteriophora against larvae of the cockchafer (Melolontha hippocastani) which were infected with rickettsia. This rickettsia causes the so called “Lorscher illness” of the white grubs. The results show that a pre-infection of the white grubs with rickettsia increases the efficiency of the nematodes about a factor of 3-6. The reproduction-rate of the nematodes in these white grubs was decreased about 50%. Nematodes which have reproduced in rickettsia-infected white grubs were less effective suggesting a decreased fitness and quality of them. We suppose a strong competition about the fat body of the white grub and a disturbed interaction of the nematodes and its symbiotic bacteria as the reason for this result. Those nematode dauerlarvae which were released from rickettsia-infected grubs were able to transport the rickettsia into the body of a health white grub but not to cause a real rickettsia infection of the grub because the efficiency and the development of the symbiotic bacteria of the nematodes are much faster. In summary we found a synergistic effect of both pathogens with regard to the efficiency and an antagonistic effect with regard to the reproduction and development of them

    Comparative Safety of the BNT162b2 Messenger RNA COVID-19 Vaccine vs Other Approved Vaccines in Children Younger Than 5 Years.

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    Importance SARS-CoV-2 vaccines are authorized for use in most age groups. The safety of SARS-CoV-2 vaccines is unknown in children younger than 5 years. Objective To retrospectively evaluate the safety of the BNT162b2 vaccine used off-label in children younger than 5 years compared with the safety of non-SARS-CoV-2 vaccines in the same sample. Design, Setting, and Participants This investigator-initiated retrospective cohort study included parents or caregivers who registered children for SARS-CoV-2 vaccination in outpatient care facilities in Germany. The study was performed as an authenticated online survey. A total of 19 000 email addresses were contacted from vaccination registration databases between April 14 and May 9, 2022. Inclusion criteria were child age younger than 5 years at the first BNT162b2 vaccination and use of a correct authentication code to prove invitation. Exposures Off-label BNT162b2 vaccination and on-label non-SARS-CoV-2 vaccinations. Main Outcomes and Measures Reported short-term safety data of 1 to 3 doses of 3 to 10 μg BNT162b2 in children from birth to younger than 60 months are presented. Coprimary outcomes were the frequencies of 11 categories of symptoms after vaccination with bivariate analyses and regression models adjusting for age, sex, weight, and height. Results The study included 7806 children (median age, 3 years [IQR, 2-4 years]; 3824 [49.0%] female) who were followed up of for a mean (SD) of 91.4 (38.8) days since first BNT162b2 vaccination (survey response rate, 41.1%). A 10-μg dosage was more frequently associated with local injection-site symptoms compared with lower dosages. In the active-comparator analysis, the probability of any symptoms (odds ratio [OR], 1.62; 95% CI, 1.43-1.84), local symptoms (OR, 1.68; 95% CI, 1.38-2.05), musculoskeletal symptoms (OR, 2.55; 95% CI, 1.32-4.94), dermatologic symptoms (OR, 2.18; 95% CI, 10.7-4.45), or otolaryngologic symptoms (OR, 6.37; 95% CI, 1.50-27.09) were modestly elevated after BNT162b2 compared with non-SARS-CoV-2 vaccines, whereas the probabilities of general symptoms (OR, 0.77; 95% CI, 0.63-0.95) and fever (OR, 0.42; 95% CI, 0.32-0.55) were lower after BNT162b2. Symptoms requiring hospitalization (n = 10) were reported only at BNT162b2 dosages above 3 μg. Conclusions and Relevance In this cohort study, the symptoms reported after BNT162b2 administration were comparable overall to those for on-label non-SARS-CoV-2 vaccines in this cohort of children younger than 5 years. The present data may be used together with prospective licensure studies of BNT162b2 efficacy and safety and could help guide expert recommendations about BNT162b2 vaccinations in this age group

    Above- and belowground biodiversity jointly tighten the P cycle in agricultural grasslands

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    Experiments showed that biodiversity increases grassland productivity and nutrient exploitation, potentially reducing fertiliser needs. Enhancing biodiversity could improve P-use efficiency of grasslands, which is beneficial given that rock-derived P fertilisers are expected to become scarce in the future. Here, we show in a biodiversity experiment that more diverse plant communities were able to exploit P resources more completely than less diverse ones. In the agricultural grasslands that we studied, management effects either overruled or modified the driving role of plant diversity observed in the biodiversity experiment. Nevertheless, we show that greater above- (plants) and belowground (mycorrhizal fungi) biodiversity contributed to tightening the P cycle in agricultural grasslands, as reduced management intensity and the associated increased biodiversity fostered the exploitation of P resources. Our results demonstrate that promoting a high above- and belowground biodiversity has ecological (biodiversity protection) and economical (fertiliser savings) benefits. Such win-win situations for farmers and biodiversity are crucial to convince farmers of the benefits of biodiversity and thus counteract global biodiversity loss

    The chemistry of sulfur and nitrogen species in a fog system A multiphase approach

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    Concentration and phase distribution of sulfur and nitrogen species during a particular fog episode in the Po Valley are experimentally described in this paper. Chemical measurements were carried out simultaneously at different heights within the fog layer, up to 50 m. Microphysical and meteorological parameters necessary for the description of the fog multiphase system were also concurrently measured as a function of height. The fog cycle (formation, evolution, dissipation) is described in terms of the total acidity of a unit volume of air containing gas species, interstitial aerosol particles and fog droplets. The fog system was not closed and input of acidic and basic components was observed during fog evolution. The driving force which determines the acidity of the fog multiphase atmospheric system was found to be the presence of NH 3 and its partitioning among the different phases. A strong decrease of fog water pH (from 5.6 down to 2.8) was observed during fog evolution and was attributed to a HNO 3 input to the system. These acidic and basic inputs are described in terms of a titration/back-titration process of the fog system. The SO 2 oxidation process in fog water was found to be of minor importance in determining the SO 4 = concentration within the fog system, due to both low SO 2 concentration and limited oxidant availability during the experiment. DOI: 10.1034/j.1600-0889.1992.t01-4-00005.

    Calcium carbonate veins in ocean crust record a threefold increase of seawater Mg/Ca in the past 30 Million years

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    Chemical (Sr, Mg) and isotopic (δ18O, 87Sr/86Sr) compositions of calcium carbonate veins (CCV) in the oceanic basement were determined to reconstruct changes in Sr/Ca and Mg/Ca of seawater in the Cenozoic. We examined CCV from 10 basement drill sites in the Atlantic and Pacific, ranging in age between 165 and 2.3 Ma. Six of these sites are from cold ridge flanks in basement <46 Ma, which provide direct information about seawater composition. CCV of these young sites were dated, using the Sr isotopic evolution of seawater. For the other sites, temperature-corrections were applied to correct for seawater–basement exchange processes. The combined data show that a period of constant/low Sr/Ca (4.46–6.22 mmol/mol) and Mg/Ca (1.12–2.03 mol/mol) between 165 and 30 Ma was followed by a steady increase in Mg/Ca ratios by a factor of three to modern ocean composition. Mg/Ca–Sr/Ca relations suggest that variations in hydrothermal fluxes and riverine input are likely causes driving the seawater compositional changes. However, additional forcing may be involved in explaining the timing and magnitude of changes. A plausible scenario is intensified carbonate production due to increased alkalinity input to the oceans from silicate weathering, which in turn is a result of subduction-zone recycling of CO2 from pelagic carbonate formed after the Cretaceous slow-down in ocean crust production rate

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    ABSTRACT. Objective. To summarize the work performed by the Outcome Measures in Rheumatology (OMERACT) Ultrasound (US) Working Group on the validation of US as a potential outcome measure in gout. Methods. Based on the lack of definitions, highlighted in a recent literature review on US as an outcome tool in gout, a series of iterative exercises were carried out to obtain consensus-based definitions on US elementary components in gout using a Delphi exercise and subsequently testing these definitions in static images and in patients with proven gout. Cohen&apos;s κ was used to test agreement, and values of 0-0.20 were considered poor, 0.20-0.40 fair, 0.40-0.60 moderate, 0.60-0.80 good, and 0.80-1 excellent. Results. With an agreement of &gt; 80%, consensus-based definitions were obtained for the 4 elementary lesions highlighted in the literature review: tophi, aggregates, erosions, and double contour (DC). In static images interobserver reliability ranged from moderate to almost perfect, and similar results were found for the intrareader reliability. In patients the intraobserver agreement was good for all lesions except DC (moderate). The Outcome Measures in Rheumatology (OMERACT) US Working Group (Appendix 1) developed a gout subgroup with the purpose of validating US as an imaging tool for gout. If this objective is achieved, US may be implemented as an outcome measure in gout. Is Ultrasound a Validated Outcome Measure in Gout? In 2013, a systematic literature review was published evaluating US as an outcome tool in gout and asymptomatic hyperuricemia 10 . The report found 18 out of 67 articles published since 1975 to be eligible for review. Described in the literature were 4 main pathologies related solely to gout: tophi, double contour sign (DC), soft tissue abnormalities, and bony lesions. The review highlighted that US was able to detect tophi using magnetic resonance imaging (MRI) as a gold standard, and this measure was found sensitive to change. The DC is an articular cartilage abnormality related to the deposition of crystals on the surface of the hyaline cartilage, which seemed specific to gout, with excellent inter-reader reliability and sensitive to change (the latter only in a very small patient population). Soft tissue pathology such as intrasynovial hyperechogenicity may be indicative of gout. US was less sensitive than MRI for diagnosing erosions (bony lesions) but more sensitive than conventional radiography, as is also known from rheumatoid arthritis studies Criterion and construct validity were assessed only for tophi, and overall there was a lack of consensus on the definitions of the 4 elementary lesions and their validity according to the OMERACT filter 13 . Current Limitations of US in Gout Assessment Despite clear interest in this imaging technique for the management of gout, the literature review clearly pointed to a lack of clear US definitions for the main 4 elementary lesions identified: tophi, DC, soft tissue hyperechogenicity (punctuate crystal aggregates), and bony lesions (erosions). This lack of consensus-based definitions impairs the ability to validate US according to the OMERACT filter and hampers widespread use of US in therapeutic clinical trials, due to the difficulty to measure the same phenomenon. In order to implement US in the management of patients with established or suspected gout the &quot;gout subgroup of the OMERACT US Working Group&quot; initiated a validation process. The first step was to obtain consensus-based definitions for the US elementary lesion as indicated by the literature review. This was accomplished by performing a Delphi exercise 14 . Thirty-five rheumatologists performing US and with an interest in gout were invited to participate, and 32 responded positively. After 3 Delphi rounds, &gt; 80% agreement was obtained for each definition Agreement was obtained to use the existing definitions for both synovitis and tenosynovitis 15 because these may be co-components in gout disease. Agreement could not be obtained to include synovitis (including Doppler activity) as an elementary lesion indicative of gout, because the presence of synovitis alone was not considered specific enough to define gout disease because it is a key component in other inflammatory arthropathies as well 14 . On the other hand, even if erosions may also be seen in other arthropathy conditions, since they may also be found extraarticularly in gout and may possibly have a slightly different appearance, it was decided to test, as part of the Delphi exercise, whether the existing definition worked also in gout. Perfect agreement was obtained to keep the definition close to the definition used for erosions in general. The second step was to test the reliability of the obtained definitions in a Web exercise consisting of static images of the elementary lesions. The Web exercise included 110 US images of the 4 lesions obtained from feet and knees and 20 of these images were shown twice in order to test both interand intrareader reliability. Twenty-seven of the 35 rheumatologists participating in the Delphi exercise participated in the reliability study. Cohen&apos;s κ was used to evaluate interand intrareader reliability. Κ values 0-0.20 were considered poor; 0.20-0.40 fair; 0.40-0.60 moderate; 0.60-0.80 good; and 0.80-1 excellent The third step was to test the agreement and reliability of the elementary lesions in a cohort of patients with gout. Sixteen of the rheumatologists previously involved in the first and second step participated in a workshop with 8 patients with crystal-proven gout. Both intra-and inter-reader reliability was assessed by scanning the patients twice within the same day. The areas of attention were the intercondylar region of the knee, the 1st metatarsophalangeal (MTP) joint, and the patellar tendon. Cohen&apos;s κ was used to evaluate inter-and intrareader reliability. Κ values of 0-0.20 were considered poor; 0.20-0.40 fair; 0.40-0.60 moderate; 0.60-0.80 good; and 0.80-1 excellen

    2023 EULAR recommendations on imaging in diagnosis and management of crystal-induced arthropathies in clinical practice

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    Objective: To formulate evidence-based recommendations and overarching principles on the use of imaging in the clinical management of crystal-induced arthropathies (CiAs). Methods: An international task force of 25 rheumatologists, radiologists, methodologists, healthcare professionals and patient research partners from 11 countries was formed according to the EULAR standard operating procedures. Fourteen key questions on the role of imaging in the most common forms of CiA were generated. The CiA assessed included gout, calcium pyrophosphate deposition disease and basic calcium phosphate deposition disease. Imaging modalities included conventional radiography, ultrasound, CT and MRI. Experts applied research evidence obtained from four systematic literature reviews using MEDLINE, EMBASE and CENTRAL. Task force members provided level of agreement (LoA) anonymously by using a Numerical Rating Scale from 0 to 10. Results: Five overarching principles and 10 recommendations were developed encompassing the role of imaging in various aspects of patient management: making a diagnosis of CiA, monitoring inflammation and damage, predicting outcome, response to treatment, guided interventions and patient education. Overall, the LoA for the recommendations was high (8.46-9.92). Conclusions: These are the first recommendations that encompass the major forms of CiA and guide the use of common imaging modalities in this disease group in clinical practice
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