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991.
Moritz F. Meyer Inga M. C. Seuthe Uta Drebber Oliver Siefer Matthias Kreppel Marcus O. Klein Stefanie Mikolajczak Jens Peter Klussmann Simon F. Preuss Christian U. Huebbers 《PloS one》2014,9(12)
Valosin-containing protein (VCP)/p97 has been shown to be associated with antiapoptotic function via activation of the nuclear factor-B (NFB) signaling pathway and with metastasizing of tumors in several studies. VCP is located on chromosome 9p13-p12, a region often deleted in oropharyngeal squamous cell carcinoma (OSCC). The clinical significance of VCP expression in OSCC however remains unclear. In this study, expression of VCP was determined in 106 patients (77 male (71.3%) and 31 female (28.7%); age-range: 34–79 years (mean age 57 years)) by immunohistochemistry and in a subset of 15 patients by quantitative PCR. HPV-DNA was detected by polymerase chain reaction and p16INK4a immunohistochemistry. The experimental findings were correlated with clinico-pathological data and survival parameters. 47.2% of all OSCC specimens were analyzed as negative or weak staining intensity for VCP. 52.8% of all specimens showed a high staining intensity for VCP. 73.1% of all patients were tested HPV-negative, 26.9% were HPV-positive. The 5-year disease-free and overall survival probabilities of all patients were 71.2% and 55.7%, respectively. No correlation could be found between HPV-status and VCP expression. VCP overexpression in HPV-negative patients was associated with significantly better 5-year disease-free survival (86.4% vs., 45.6%, p = 0.017). The level of VCP-intensity determined by immunohistochemistry could be an additional prognostic marker in HPV-negative OSCC. VCP expression seems not to correlate with the HPV-status. 相似文献
992.
Kirsten Falk Uta Friedrich Goddert von Oheimb Kerstin Mischke Konrad Merkle Hartmut Meyer Werner Härdtle 《Plant Ecology》2010,209(1):47-56
In the present study we analysed whether airborne N pollution may constitute one important driver for the encroachment of
Molinia caerulea in dry heathland ecosystems. Based on full-factorial field experiments (in 2006 and 2008) and complementary greenhouse experiments
(in 2008), we quantified growth responses of Molinia caerulea to N and P fertilisation (50 kg N ha−1 year−1, 20 kg P ha−1 year−1). Aboveground biomass production of Molinia
caerulea was limited by P in 2006, but by N in both experiments in 2008. In the greenhouse experiment, N addition caused a sixfold
increase of the biomass of vegetative tillers, and in all experiments the biomass and numbers of flowering tillers showed
a significant increase due to fertilisation. Our experiments indicated that growth of Molinia caerulea was primarily limited by N, but in dry heaths the kind of nutrient limitation may be mediated by other factors such as water
availability during the vegetative period. Shifts in biomass allocation patterns resulting from N fertilisation showed that
Molinia
caerulea encroachment in dry heaths is not only attributable to increased leaf biomass, but also due to higher investments in reproductive
tissue that allow for increased seed production and thus accelerated encroachment of seedlings in places where the dwarf shrub
canopy has been opened after disturbance. 相似文献
993.
Anna-Lisa Wrange Johanna Valero Lisbeth S. Harkestad Øivind Strand Susanne Lindegarth Helle Torp Christensen Per Dolmer Per Sand Kristensen Stein Mortensen 《Biological invasions》2010,12(5):1145-1152
The Pacific oyster (Crassostrea gigas) is an important aquaculture species world-wide. Due to its wide environmental tolerance and high growth rate, it has also
become a successful invader in many areas, leading to major ecosystem changes. Low water temperatures were previously believed
to restrict the establishment of Pacific oysters in Scandinavia. However, recent surveys reveal that the Pacific oyster is
now established in many areas in Scandinavia. We present data on the current distribution, abundance and age-structure in
Denmark, Sweden and Norway. The biomass of oysters in the Danish Wadden Sea increased from 1,056 to 6,264 tonnes between 2005
and 2007. Massive settlements were observed along the Swedish west coast in 2007, with densities >400 oysters per m−2. In Norway, populations are established on the southern coast, and specimens have been found as far north as 60°N. The potential
impacts and probable causes of this recent large-scale establishment are discussed. 相似文献
994.
Background: Studies indicate that differences in trait anxiety and trauma-related distress may mediate the gender differences observed in posttraumatic stress disorder (PTSD).Objective: We examined the contributions of gender, trait anxiety, and trauma-related distress to the development of PTSD after an industrial disaster.Methods: Three months after a massive explosion in a fireworks factory in Kolding, Denmark, in November 2004, residents in the surrounding area were asked to complete the Harvard Trauma Questionnaire, the General Health Questionnaire, and a questionaire designed for the present study. Using multivariable logistic regression with PTSD as the dependent variable, we examined 4 explanatory models: (1) gender; (2) gender and trait anxiety; (3) gender, trait anxiety, and perceived danger; and (4) gender, trait anxiety, perceived danger, perceived hostility, feeling isolated, depersonalization, and behavioral self-blame.Results: Fifty-one percent (N = 516; 265 women and 251 men) of the area residents participated in the study. The female-to-male ratio of PTSD was 2.4:1. Women experienced significantly more trait anxiety (P < 0.001), feelings of isolation (P < 0.005), and behavioral self-blame (P = 0.018), and less perceived danger (P = 0.034) than did men. In multivariable logistic regression analysis, gender alone predicted 3.7% of the variance in PTSD status (odds ratio [OR] = 2.40; 95% CI, 1.35-4.27; P < 0.005); however, in all other models, gender was not significant. The final model comprised trait anxiety (OR = 1.20; 95% CI, 1.11-1.30; P < 0.001), perceived danger (OR = 4.62; 95% Cl, 2.24-9.50; P < 0.001), perceived hostility (OR = 5.21; 95% CI, 1.93-14.09; P < 0.001), feeling isolated (OR = 3.34; 95% CI, 1.55-7.16; P < 0.002), depersonalization (OR = 2.49; 95% CI, 1.42-4.37; P < 0.001), and behavioral self-blame (OR = 0.46; 95% CI, 0.24-0.86; P = 0.015), explaining 48.9% of the variance in PTSD severity.Conclusion: This cross-sectional study found that gender was no longer associated with PTSD status when trait anxiety, perceived danger and hostility, feeling isolated, depersonalization, and behavioral selfblame were taken into account. 相似文献
995.
996.
Jens Wiegand Guido Aschan Uta Kraus Judith Piontek Joachim Mederer 《Soil & Sediment Contamination》2009,18(1):14-29
The presented study assessed the heavy metal contamination risk in a former sludge deposit field of the River Ruhr in Essen, Germany. Therefore, the temporal and spatial distribution in soils and plants, chemical fractionation, mobilization potential, and transfer characteristics have been investigated. Soil samples, roots and shoots of rushes (Juncus sp.), and stem wood disks of willows (Salix sp.) were analyzed for Zn, Cu, Pb, Ni, Cr, and Cd. Plant available and mobile heavy metal portions have been determined using a sequential extraction procedure. The results show that the soils and the rushes are highly contaminated, although there is a considerable decrease compared to initial concentrations some 20 years ago. The willows show only small heavy metal enrichment. pH induced mobilization potential in soil is high for Cd, Zn and Ni. Additionally, these elements contain high portions of plant-available fractions. High transfer rates from soil to roots and very high rates from roots to shoots of rushes have been determined for Cd and Zn, indicating an accumulation of these elements in shoots of rushes. The rushes reflect the temporal and spatial heavy metal distribution in soil and might thus be used as a bioindicator or for phytoremediation. 相似文献
997.
David A. Gunn Helle Rexbye Christopher E. M. Griffiths Peter G. Murray Amelia Fereday Sharon D. Catt Cyrena C. Tomlin Barbara H. Strongitharm Dave I. Perrett Michael Catt Andrew E. Mayes Andrew G. Messenger Martin R. Green Frans van der Ouderaa James W. Vaupel Kaare Christensen 《PloS one》2009,4(12)
The desire of many to look young for their age has led to the establishment of a large cosmetics industry. However, the features of appearance that primarily determine how old women look for their age and whether genetic or environmental factors predominately influence such features are largely unknown. We studied the facial appearance of 102 pairs of female Danish twins aged 59 to 81 as well as 162 British females aged 45 to 75. Skin wrinkling, hair graying and lip height were significantly and independently associated with how old the women looked for their age. The appearance of facial sun-damage was also found to be significantly correlated to how old women look for their age and was primarily due to its commonality with the appearance of skin wrinkles. There was also considerable variation in the perceived age data that was unaccounted for. Composite facial images created from women who looked young or old for their age indicated that the structure of subcutaneous tissue was partly responsible. Heritability analyses of the appearance features revealed that perceived age, pigmented age spots, skin wrinkles and the appearance of sun-damage were influenced more or less equally by genetic and environmental factors. Hair graying, recession of hair from the forehead and lip height were influenced mainly by genetic factors whereas environmental factors influenced hair thinning. These findings indicate that women who look young for their age have large lips, avoid sun-exposure and possess genetic factors that protect against the development of gray hair and skin wrinkles. The findings also demonstrate that perceived age is a better biomarker of skin, hair and facial aging than chronological age. 相似文献
998.
Lõivukene K Kermes K Sepp E Adamson V Mitt P Jürna M Mägi H Kallandi U Otter K Naaber P 《Antonie van Leeuwenhoek》2006,89(3-4):367-371
A total of 560 invasive and 1062 non-invasive isolates were collected. The antimicrobial susceptibility of invasive versus non-invasive Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae isolates were evaluated using the E-tests. The equal domination of Gram-negative among both invasive and non-invasive pathogens was estimated in our study if contaminants were excluded. The emergence trend of Gram-positive microbes especially of coagulase negative staphylococci may be proved only after application of exclusive algorithms. Due to similar susceptibility, the data of non-invasive Gram-negative pathogens can be useful to predict resistance of invasive ones. Also, the surveillance of invasive pathogens provides useful information about the general susceptibility of pathogens. 相似文献
999.
Huus K Havelund S Olsen HB Sigurskjold BW van de Weert M Frokjaer S 《Biochemistry》2006,45(12):4014-4024
The influence of ligand binding and conformation state on the thermostability of hexameric zinc-insulin was studied by differential scanning calorimetry (DSC). The insulin hexamer exists in equilibrium between the forms T6, T3R3, and R6. Phenolic ligands induce and stabilize the T3R3- and R6-states which are further stabilized by binding of certain anions that do not stabilize the T6-state. It was shown that the thermostability of the resorcinol-stabilized R6-state was significantly higher than that of the T6-state. Further analysis showed that phenol- and m-cresol-stabilized R6-hexamer loses three ligands before reaching the unfolding temperature and hence unfolds from the T3R3-state. The relative affinity of the four tested anionic ligands was found, by DSC, to be thiocyanate > or = 4-hydroxy-3-nitrobenzoate > p-aminobenzoate > chloride. The results correlate with other methods and demonstrate that DSC provides a general and useful method of evaluation of both phenolic and anionic ligand binding to insulin without the use of probes or other alterations of the system of interest. However, it is a prerequisite that the binding is strong enough to saturate the binding sites at temperatures around the unfolding transition. 相似文献
1000.
Cizmecioglu O Arnold M Bahtz R Settele F Ehret L Haselmann-Weiss U Antony C Hoffmann I 《The Journal of cell biology》2010,191(4):731-739
Both gain and loss of function studies have identified the Polo-like kinase Plk4/Sak as a crucial regulator of centriole biogenesis, but the mechanisms governing centrosome duplication are incompletely understood. In this study, we show that the pericentriolar material protein, Cep152, interacts with the distinctive cryptic Polo-box of Plk4 via its N-terminal domain and is required for Plk4-induced centriole overduplication. Reduction of endogenous Cep152 levels results in a failure in centriole duplication, loss of centrioles, and formation of monopolar mitotic spindles. Interfering with Cep152 function prevents recruitment of Plk4 to the centrosome and promotes loss of CPAP, a protein required for the control of centriole length in Plk4-regulated centriole biogenesis. Our results suggest that Cep152 recruits Plk4 and CPAP to the centrosome to ensure a faithful centrosome duplication process. 相似文献