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101.
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Ulrich Claussen Wanda Zevenboom Uwe Brockmann Dilek Topcu Peter Bot 《Hydrobiologia》2009,629(1):49-58
Eutrophication (nutrient enrichment and subsequent processes) and its adverse ecosystem effects have been discussed as main
issues over the last 20 years in international conferences and conventions for the protection of the marine environment such
as the North Sea Conferences and the 1992 OSPAR Convention (OSPAR; which combined and updated the 1972 Oslo Convention on
dumping waste at the sea and the 1974 Paris Convention on land-based sources of marine pollution). OSPAR committed itself
to reduce phosphorus and nitrogen inputs (in the order of 50% compared with 1985) into the marine areas and ‘to combat eutrophication
to achieve, by the year 2010, a healthy marine environment where eutrophication does not occur’. Within OSPAR, the Comprehensive
Procedure (COMPP) has been developed and used to assess the eutrophication status of the OSPAR maritime area in an harmonised
way. This is based on classification in terms of the following types of areas Non-Problem Areas (no effects), Potential Problem
Areas (not enough data to assess effects) and Problem Areas (effects due to elevated nutrients and/or due to transboundary
transport from adjacent areas). The COMPP consists of a set of harmonised assessment criteria with their area-specific assessment
levels and an integrated area classification approach. The criteria cover all aspects of nutrient enrichment (nutrient inputs,
concentrations and ratios) as well as possible direct effects (e.g. increased levels of nuisance and/or toxic phytoplankton
species, shifts and/or losses of submerged aquatic vegetation) and indirect effects (e.g. oxygen deficiency, changes and/or
death of benthos, death of fish, algal toxins). The COMPP also includes supporting environmental factors. It takes account
of synergies and harmonisation with the EC Water Framework Directive, and has formed a major basis for the EC eutrophication
guidance. Recently, additional components, such as total nitrogen, total phosphorus and transboundary transports have been
included in the assessment of, e.g. the German Bight. The second application of the COMPP resulting in an update of the eutrophication
status of the OSPAR maritime area will be finalised in 2008, and will include the agreed integrated set of Ecological Quality
Objectives (EcoQOs) with respect to eutrophication.
Guest editors: J. H. Andersen & D. J. Conley
Eutrophication in Coastal Ecosystems: Selected papers from the Second International Symposium on Research and Management of
Eutrophication in Coastal Ecosystems, 20–23 June 2006, Nyborg, Denmark 相似文献
104.
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Wanda Małek Sylwia Wdowiak-Wróbel Michał Bartosik Grażyna Konopa Magdalena Narajczyk 《Current microbiology》2009,59(2):187-192
Three lytic phages (ΦRP1, ΦRP2, and ΦRP3) specific for Robinia pseudoacacia rhizobia were isolated from the soil under black locust. They were characterized by their morphology, host range, and some
other properties including DNA molecular weights. Studied phages have been found to belong to Siphoviridae family that comprises viruses with long, and noncontractile tails. They had broad host ranges and effectively lysed not only
Robinia pseudoacacia microsymbionts but also different Mesorhizobium species. The phages were homogenous in latent periods (300 min) but heterogeneous in burst sizes (100–200 phage particles
per one infected cell) and rise periods (90–120 min). They showed a distinct adsorption rate to Robinia pseudoacacia rhizobia (70.4–93.94%). The molecular weights of phage DNAs estimated from restriction enzyme digests were in the range from
ca. 82 kb to ca. 105 kb. 相似文献
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107.
Margaret L. Van Keuren Galina B. Gavrilina Wanda E. Filipiak Michael G. Zeidler Thomas L. Saunders 《Transgenic research》2009,18(5):769-785
Transgenic mice are widely used in biomedical research to study gene expression, developmental biology, and gene therapy models.
Bacterial artificial chromosome (BAC) transgenes direct gene expression at physiological levels with the same developmental
timing and expression patterns as endogenous genes in transgenic animal models. We generated 707 transgenic founders from
86 BAC transgenes purified by three different methods. Transgenesis efficiency was the same for all BAC DNA purification methods.
Polyamine microinjection buffer was essential for successful integration of intact BAC transgenes. There was no correlation
between BAC size and transgenic rate, birth rate, or transgenic efficiency. A narrow DNA concentration range generated the
best transgenic efficiency. High DNA concentrations reduced birth rates while very low concentrations resulted in higher birth
rates and lower transgenic efficiency. Founders with complete BAC integrations were observed in all 47 BACs for which multiple
markers were tested. Additional founders with BAC fragment integrations were observed for 65% of these BACs. Expression data
was available for 79 BAC transgenes and expression was observed in transgenic founders from 63 BACs (80%). Consistent and
reproducible success in BAC transgenesis required the combination of careful DNA purification, the use of polyamine buffer,
and sensitive genotyping assays. 相似文献
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109.
Carla Maria P. Ribeiro Harry Hurd Yichao Wu Mary E. B. Martino Lisa Jones Brian Brighton Richard C. Boucher Wanda K. O'Neal 《PloS one》2009,4(6)
Prolonged macrolide antibiotic therapy at low doses improves clinical outcome in patients affected with diffuse panbronchiolitis and cystic fibrosis. Consensus is building that the therapeutic effects are due to anti-inflammatory, rather than anti-microbial activities, but the mode of action is likely complex. To gain insights into how the macrolide azithromycin (AZT) modulates inflammatory responses in airways, well-differentiated primary cultures of human airway epithelia were exposed to AZT alone, an inflammatory stimulus consisting of soluble factors from cystic fibrosis airways, or AZT followed by the inflammatory stimulus. RNA microarrays were conducted to identify global and specific gene expression changes. Analysis of gene expression changes revealed that the AZT treatment alone altered the gene profile of the cells, primarily by significantly increasing the expression of lipid/cholesterol genes and decreasing the expression of cell cycle/mitosis genes. The increase in cholesterol biosynthetic genes was confirmed by increased filipin staining, an index of free cholesterol, after AZT treatment. AZT also affected genes with inflammatory annotations, but the effect was variable (both up- and down-regulation) and gene specific. AZT pretreatment prevented the up-regulation of some genes, such as MUC5AC and MMP9, triggered by the inflammatory stimulus, but the up-regulation of other inflammatory genes, e.g., cytokines and chemokines, such as interleukin-8, was not affected. On the other hand, HLA genes were increased by AZT. Notably, secreted IL-8 protein levels did not reflect mRNA levels, and were, in fact, higher after AZT pretreatment in cultures exposed to the inflammatory stimulus, suggesting that AZT can affect inflammatory pathways other than by altering gene expression. These findings suggest that the specific effects of AZT on inflamed and non-inflamed airway epithelia are likely relevant to its clinical activity, and their apparent complexity may help explain the diverse immunomodulatory roles of macrolides. 相似文献
110.
Sherita Hill Golden Wendy L. Bennett Kesha Baptist-Roberts Lisa M. Wilson Bethany Barone Tiffany L. Gary Eric Bass Wanda K. Nicholson 《Gender Medicine》2009
Background: Women with a history of gestational diabetes mellitus (GDM) are at high risk for type 2 diabetes mellitus (T2DM).Objective: We reviewed prospective studies of antepartum glucose tolerance test results as risk factors for development of T2DM among women with a history of GDM.Methods: We searched 4 electronic databases and hand-searched 13 journals for literature published through January 2007. The search strategy consisted of medical subject headings and text words for GDM, T2DM, and other relevant terms. Articles were excluded for the following reasons: (1) not written in English; (2) no human data; (3) no original data; (4) <90% of sample was diagnosed with GDM without a separate analysis for women with GDM; (5) case report or series; (6) diagnosis of GDM not based on 3-hour 100-g oral glucose tolerance test (OGTT) or 2-hour 75-g OGTT; (7) T2DM not evaluated as outcome; (8) no relative measure of association or incidence reported; or (9) design did not address antepartum OGTT as a predictor of T2DM. Two investigators independently reviewed citations, performed serial data abstraction on full articles, and assessed the quality of each article. Data were abstracted for study participants and characteristics, T2DM diagnosis, length of follow-up, regression model covariates, and measures of association and variability.Results: Of 11,400 unique citations, we identified 11 articles that evaluated antepartum glucose testing and risk of T2DM in women with a history of GDM. Five studies found that the fasting blood glucose (FBG) on the antepartum diagnostic OGTT was a significant predictor of T2DM (odds ratio [OR] range: 11.1–21.0; relative risk [RR] range: 1.37–1.5; relative hazard [RH] = 2.47). Risk of incident T2DM was predicted by the antepartum 2-hour OGTT plasma glucose in 3 studies (OR range: 1.02–1.03; RR = 1.3) and by the antepartum OGTT glucose AUC in 3 other studies (OR range: 3.64–15; RH = 2.13). Overall, study quality was limited by high losses to follow-up (>20% in 6 studies) and short duration. Few studies adjusted for adiposity, an established diabetes risk factor.Conclusion: FBG, OGTT 2-hour blood glucose, and OGTT glucose AUC appeared to be strong and consistent predictors of subsequent T2DM among women who met diagnostic criteria for GDM using the OGTT. 相似文献