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Species diversity depends on, often interfering, multiple ecological drivers. Comprehensive approaches are hence needed to understand the mechanisms determining species diversity. In this study, we analysed the impact of vegetation structure, soil properties and fragmentation on the plant species diversity of remnant calcareous grasslands, therefore, in a comparative approach. We determined plant species diversity of 18 calcareous grasslands in south eastern Germany including all species and grassland specialists separately. Furthermore, we analysed the spatial structure of the grasslands as a result of fragmentation during the last 150 years (habitat area, distance to the nearest calcareous grassland and connectivity in 1830 and 2013). We also collected data concerning the vegetation structure (height of the vegetation, cover of bare soil, grass and litter) and the soil properties (content of phosphorous and potassium, ratio of carbon and nitrogen) of the grassland patches. Data were analysed using Bayesian multiple regressions. We observed a habitat loss of nearly 80% and increasing isolation between grasslands since 1830. In the Bayesian multiple regressions the species diversity of the studied grasslands depended negatively on cover of litter and to a lower degree on the distance to the nearest calcareous grassland in 2013, whereas soil properties had no significant impact. Our study supports the observation that vegetation structure, which strongly depends on land use, is often more important for the species richness of calcareous grasslands than fragmentation or soil properties. Even small and isolated grasslands may, therefore, contribute significantly to the conservation of species diversity, when they are still grazed. [ABSTRACT FROM AUTHOR]

Abstract: In the course of this study, examinations were carried out to develop a PCR-based test which allows discrimination of Brucella species and biovars not targeted by the currently established gel-based PCR assays. Appropriate primers were designed based on specific deletions and insertions in the different Brucella genomes as determined by RAPD-PCR and whole-genome comparisons. After testing the specificity of the primers with a set of 22 Brucella reference strains of all species and biovars, they were used to supplement the existing PCR assays resulting in a 19-primer multiplex PCR. In addition to the commonly used PCR assays, the developed assay specifically identified B. neotomae, B. pinnipedialis, B. ceti, and B. microti. Furthermore, it differentiated B. abortus biovars 1, 2, 4 from biovars 3, 5, 6, 9, as well as between B. suis biovar 1, biovars 3, 4, and biovars 2 and 5. When tested in the multiplex assay, all Brucella type and reference strains and the majority of 118 field strains examined could be accurately identified by their respective banding patterns according to their previous typing. B. canis strains were subdivided into 2 groups, one exhibiting a unique pattern and the other one a banding pattern shared with B. suis biovars 3 and 4. Species of the closely related genus Ochrobactrum and several other clinically relevant bacteria showed no amplification product. Hence, the developed PCR assay is useful for rapid identification of Brucella at the species and at the biovar level. [Copyright &y& Elsevier]

Background: Specific immunotherapy acts to modify the underlying cause of allergic rhinoconjunctivitis. Addition of adjuvants, such as monophosphoryl lipid A (MPL), might allow for efficacious and safe treatment with only 4 injections administered preseasonally, which is in contrast to most available schedules requiring long injection courses. Objective: The primary objective was to assess the clinical efficacy of Ragweed MATA MPL (short ragweed pollen allergoid adsorbed to L-Tyrosine + MPL) versus placebo in reducing allergic rhinoconjunctivitis symptoms caused by ragweed pollen in an environmental exposure chamber (EEC) 3 weeks after treatment. Methods: This was a randomized, double-blind, placebo-controlled phase IIb study to evaluate the clinical efficacy and safety of Ragweed MATA MPL compared with placebo by using controlled ragweed pollen exposure in an EEC. Two hundred twenty-eight patients with a history of ragweed allergy and positive skin prick test responses to ragweed were randomized and received 4 weekly injections of active treatment or placebo. Total nasal and nonnasal symptom scores were obtained in the EEC before and after treatment. Results: Mean improvement in total symptom scores in the Ragweed MATA MPL group was statistically significantly greater than in the placebo group (relative mean improvement of active vs placebo, 48%; P < .05; median improvement, 82%). The majority of adverse events (AEs) experienced by subjects were mild injection-site reactions. No severe systemic AEs or serious AEs occurred during the study. Conclusion: This study demonstrated that an ultrashort course of Ragweed MATA MPL is efficacious in reducing allergy symptoms in patients with seasonal allergic rhinitis and that it is well tolerated. [Copyright &y& Elsevier]