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91.
Sebastian Ocklenburg Wanda M. Gerding Maximilian Raane Larissa Arning Erhan Genç Jörg T. Epplen Onur Güntürkün Christian Beste 《Molecular neurobiology》2018,55(10):7691-7700
Molecular neurobiological factors determining corpus callosum physiology and anatomy have been suggested to be one of the major factors determining functional hemispheric asymmetries. Recently, it was shown that allelic variations in two myelin-related genes, the proteolipid protein 1 gene PLP1 and the contactin 1 gene CNTN1, are associated with differences in interhemispheric integration. Here, we investigated whether three single nucleotide polymorphisms that were associated with interhemispheric integration via the corpus callosum in a previous study also are relevant for functional hemispheric asymmetries. To this end, we tested more than 900 healthy adults with the forced attention dichotic listening task, a paradigm to assess language lateralization and its modulation by cognitive control processes. Moreover, we used the line bisection task, a paradigm to assess functional hemispheric asymmetries in spatial attention. We found that a polymorphism in PLP1, but not CNTN1, was associated with performance differences in both tasks. Both functional hemispheric asymmetries and their modulation by cognitive control processes were affected. These findings suggest that both left and right hemisphere dominant cognitive functions can be modulated by allelic variation in genes affecting corpus callosum structure. Moreover, higher order cognitive processes may be relevant parameters when investigating the molecular basis of hemispheric asymmetries. 相似文献
92.
Zinc and cadmium analysis in human prostate neoplasms 总被引:4,自引:0,他引:4
Magdalena Brys Agnieszka D. Nawrocka Eügeniüsz MlekoŚ Cezary Zydek Marek Foksinski Andrzej Barecki Wanda M. Krajewska 《Biological trace element research》1997,59(1-3):145-152
The objective of this study was to test the hypothesis that prostatic cancer is associated with the changes of zinc (Zn) and
cadmium (Cd) concentration. Normal prostate, benign prostatic hyperplasia (BPH), and prostatic carcinoma (PCA) were analyzed
for Zn and Cd by atomic absorption spectrometry. Cd level was measured using a graphite furnace and Zn level was measured
by flame mode. Metal content was assessed in whole tissues and in nuclear, plasma membrane, and cytosolic fractions. An increase
of Zn content in BPH, but a decrease in PCA as compared to normal tissue, was observed. Cd concentration appeared to be higher
in BPH and PCA than in normal tissue. No correlation between Zn and Cd level was found in BPH specimens obtained from the
same patients. Probability values ofp ≤0.05 were considered to indicate significant differences. Obtained results seem to support the hypothesis of Cd carcinogenicity
and preventing function of Zn in prostatic cancer. Plasma membrane fraction corresponding to lysosomal, mitochondrial, and
microsomal subcellular compartments are probably critical in Zn and Cd participation in human prostate neoplasms. 相似文献
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96.
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
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98.
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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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