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141.
Joanna Szkandera Michael Stotz Florian Eisner Gudrun Absenger Tatjana Stojakovic Hellmut Samonigg Peter Kornprat Renate Schaberl-Moser Wael AlZoughbi Anna Lena Ress Friederike Sophia Seggewies Armin Gerger Gerald Hoefler Martin Pichler 《PloS one》2013,8(11)
Background
With growing evidence on the role of inflammation in cancer biology, the presence of a systemic inflammatory response has been postulated as having prognostic significance in a wide range of cancer types. The derived neutrophil to lymphocyte ratio (dNLR), which represents an easily determinable potential prognostic marker in daily practise and clinical trials, has never been externally validated in pancreatic cancer (PC) patients.Methods
Data from 474 consecutive PC patients, treated between 2004 and 2012 at a single centre, were evaluated retrospectively. Cancer-specific survival (CSS) was assessed using the Kaplan-Meier method. To evaluate the prognostic relevance of dNLR, univariate and multivariate Cox regression models were applied.Results
We calculated by ROC analysis a cut-off value of 2.3 for the dNLR to be ideal to discriminate between patients’ survival in the whole cohort. Kaplan-Meier curve reveals a dNLR≥2.3 as a factor for decreased CSS in PC patients (p<0.001, log-rank test). An independent significant association between high dNLR≥2.3 and poor clinical outcome in multivariate analysis (HR = 1.24, CI95% = 1.01–1.51, p = 0.041) was identified.Conclusion
In the present study we confirmed elevated pre-treatment dNLR as an independent prognostic factor for clinical outcome in PC patients. Our data encourage independent replication in other series and settings of this easily available parameter as well as stratified analysis according to tumor resectability. 相似文献142.
Mucha Joanna Zadworny Marcin Helmisaari Heljä-Sisko Nihlgård Bengt Repo Tapani Żytkowiak Maciej Małek Stanisław Reich Peter B. Oleksyn Jacek 《Plant and Soil》2020,455(1-2):507-518
Plant and Soil - Any grouping of tree species concerned with SOC sequestration should include trees that are as homogeneous as possible in their carbon sequestration. We propose a classification of... 相似文献
143.
Muszyńska Bożena Kała Katarzyna Włodarczyk Anna Krakowska Agata Ostachowicz Beata Gdula-Argasińska Joanna Suchocki Piotr 《Biological trace element research》2020,194(2):614-615
Biological Trace Element Research - The original version of this article unfortunately contained a mistake. 相似文献
144.
Alexandra K. Fraik Mark J. Margres Brendan Epstein Soraia Barbosa Menna Jones Sarah Hendricks Barbara Schönfeld Amanda R. Stahlke Anne Veillet Rodrigo Hamede Hamish McCallum Elisa Lopez-Contreras Samantha J. Kallinen Paul A. Hohenlohe Joanna L. Kelley Andrew Storfer 《Evolution; international journal of organic evolution》2020,74(7):1392-1408
Landscape genomics studies focus on identifying candidate genes under selection via spatial variation in abiotic environmental variables, but rarely by biotic factors (i.e., disease). The Tasmanian devil (Sarcophilus harrisii) is found only on the environmentally heterogeneous island of Tasmania and is threatened with extinction by a transmissible cancer, devil facial tumor disease (DFTD). Devils persist in regions of long-term infection despite epidemiological model predictions of species’ extinction, suggesting possible adaptation to DFTD. Here, we test the extent to which spatial variation and genetic diversity are associated with the abiotic environment (i.e., climatic variables, elevation, vegetation cover) and/or DFTD. We employ genetic-environment association analyses using 6886 SNPs from 3287 individuals sampled pre- and post-disease arrival across the devil's geographic range. Pre-disease, we find significant correlations of allele frequencies with environmental variables, including 365 unique loci linked to 71 genes, suggesting local adaptation to abiotic environment. The majority of candidate loci detected pre-DFTD are not detected post-DFTD arrival. Several post-DFTD candidate loci are associated with disease prevalence and were in linkage disequilibrium with genes involved in tumor suppression and immune response. Loss of apparent signal of abiotic local adaptation post-disease suggests swamping by strong selection resulting from the rapid onset of DFTD. 相似文献
145.
The skin constitutes a formidable barrier against commensal and pathogenic bacteria, which permanently and transiently colonise the skin, respectively. Commensal and pathogenic species inhabiting skin both express proteases. Whereas proteases secreted by commensals contribute to homeostatic bacterial coexistence on skin, proteases from pathogenic bacteria are used as virulence factors, helping them colonise skin with breached integrity of the epithelial layer. From these initial sites of colonisation, pathogens can disseminate into deeper layers of skin, possibly leading to the spread of infection. Secreted bacterial proteases probably play an important role in this process and in the deterrence of innate defence mechanisms. For example, Staphylococcus aureus proteases are essential for changing the bacterial phenotype from adhesive to invasive by degrading adhesins on the bacterial cell surface. Secreted staphylococcal proteases mediate pathogen penetration by degrading collagen and elastin, essential components of connective tissue in the dermis. The activation of the contact system and kinin generation by Streptococcus pyogenes and S. aureus proteases contributes to an inflammatory reaction manifested by oedema, redness and pain. Kinin-enhanced vascular leakage might help bacteria escape into the circulation thereby causing possible systemic dissemination of the infection. The inflammatory reaction can also be fueled by the activation of protease-activated receptors on keratinocytes. Concomitantly, bacterial proteases are involved in degrading antimicrobial peptides, disarming the complement system and neutrophils and preventing the infiltration of the infected sites with immune cells by inactivation of chemoattractants. Together, this provides protection for colonising and/or invading pathogens from attack by antibacterial forces of the skin. 相似文献
146.
Małgorzata Jarmuz-Szymczak Kinga Pelinska Magdalena Kostrzewska-Poczekaj Ewa Bembnista Maciej Giefing Damian Brauze Marcin Szaumkessel Andrzej Marszalek Joanna Janiszewska Katarzyna Kiwerska Anna Bartochowska Reidar Grenman Witold Szyfter Krzysztof Szyfter 《Molecular biology reports》2013,40(7):4161-4171
We reinvestigated rearrangements occurring in region q13 of chromosome 11 aiming to: (i) describe heterogeneity of the observed structural alterations, (ii) estimate amplicon size and (iii) identify of oncogenes involved in laryngeal cancer progression as potential targets for therapy. The study included 17 cell lines derived from laryngeal cancers and 34 specimens from primary laryngeal tumors. The region 11q13 was analyzed by fluorescence in situ hybridization (FISH), array comparative genomic hybridization (aCGH) and gene expression microarray. Next, quantitative real time PCR was used for chosen genes to confirm results from aCGH and gene expression microarray. The observed pattern of aberrations allows to distinguish three ways, in which gain and amplification involving 11q13 region may occur: formation of a homogeneously staining region; breakpoints in/near 11q13, which lead to the three to sevenfold increase of the copy number of 11q13 region; the presence of additional copies of the whole chromosome 11. The minimal altered region of gain and/or amplification was limited to ~1.8 Mb (chr.11:69,395,184–71,209,568) and comprised mostly 11q13.3 band which contain 12 genes. Five, out of these genes (CCND1, ORAOV1, FADD, PPFIA1, CTTN) had higher expression levels in comparison to healthy controls. Apart from CCND1 gene, which has an established role in pathogenesis of head and neck cancers, CTTN, ORAOV1 and FADD genes appear to be oncogene-candidates in laryngeal cancers, while a function of PPFIA1 requires further studies. 相似文献
147.
148.
Edward J. O'Loughlin Phil Larese-Casanova Michelle Scherer Russell Cook 《Geomicrobiology journal》2013,30(3-4):211-230
Green rusts are mixed ferrous/ferric hydroxides that typically form under weakly acidic to alkaline conditions in suboxic environments. The recent identification of green rusts as products of the reduction of Fe(III) oxides and oxyhydroxides by Shewanella putrefaciens, a dissimilatory iron-reducing bacterium (DIRB), suggests that green rusts may play a role in the redox cycling of Fe in many aquatic and terrestrial environments. We examined the potential for green rust formation resulting from the bioreduction of lepidocrocite(γ -FeOOH) by a series of Shewanella species (S. alga BrY, S. amazonensis SB2B, S. baltica OS155, S. denitrificans OS217T, S. loihica PV-4, S. oneidensis MR-1, S. putrefaciens ATCC 8071, S. putrefaciens CN32, S. saccharophilia, and Shewanella sp. ANA-3). All Shewanella species, with the exception of S. denitrificans OS217T, were able to couple the oxidation of formate to the reduction of Fe(III) in lepidocrocite; however there were significant differences among species with respect to the rate and extent of Fe(II) production. Despite these differences, green rust was the only Fe(II)-bearing solid phase formed under our experimental conditions, as indicated by X-ray diffraction, Mössbauer spectroscopy, and scanning electron microscopy. The formation of green rust by Shewanella species isolated from a wide range of habitats and possessing varied metabolic capabilities suggests that under favorable conditions biogenic green rusts may be formed by a diverse array of DIRB. 相似文献
149.
Colin A. Chapman Tyler R. Bonnell Jan F. Gogarten Joanna E. Lambert Patrick A. Omeja Dennis Twinomugisha Michael D. Wasserman Jessica M. Rothman 《International journal of primatology》2013,34(1):1-14
Animals can play important roles in structuring the plant communities in which they live. Some species are particularly influential in that they modify the physical environment by changing, maintaining, and/or creating new habitats; the term ecosystem engineer has been used to describe such species. We here assess the two major foraging strategies of primates, frugivory and folivory, in terms of the potential for primates to function as ecosystem engineers. We argue that whereas the role of primates as seed dispersers has received a great deal of attention, the potential role that folivorous primates play in structuring their environment through herbivory has received much less attention. Further, while quantifying if frugivorous primates are ecosystem engineers through their seed dispersal has proved very difficult, it is not as difficult to ascertain whether folivorous primates are ecosystem engineers. We document situations in which folivorous primates act as ecosystem engineers by 1) eating the leaves and/or bark of trees to the extent that they kill trees, 2) feeding on trees to the degree that they slow their growth relative to nonpreferred tree species, 3) eating the flowers of species to the extent that it does not set fruit, or 4) feeding on plants in such a way as to increase their productivity and abundance. Because evidence from the literature is very limited, where possible we present new evidence of these processes from the colobus monkeys at our long-term field site in Kibale National Park, Uganda. We conclude by discussing promising research programs that could be established to refine our understanding of the role primates play in shaping the structure of plant communities, especially tropical forests. 相似文献
150.
Joanna Suliburska Paweł Bogdański Monika Szulińska 《Biological trace element research》2013,151(2):263-268
The aim of this study was to assess the metabolic and physiological changes in rats fed a diet high in fat, fructose, and salt, and with excess iron level. Mineral status was also estimated. Wistar rats were assigned to groups fed either a standard control diet (C) or a diet high in fat, fructose, and salt. The noncontrol diets contained either normal (M) or high level (MFe) of iron. After 6 weeks, the length and weight of the rats were measured, and the animals were euthanized. The kidneys and gonads were collected, and blood samples were taken. Serum levels of insulin, nitric oxide, and iron were measured. The iron, zinc, copper, and calcium concentrations of tissues were determined. It was found that the M diet led to a significant increase in the relative kidney mass of the rats compared with the control group. Among the rats fed the M diet, markedly higher serum level of iron and lower levels of zinc and copper were observed in tissues, while significantly higher calcium levels were found in the gonads. The MFe diet resulted in decreased obesity index, insulin level, and nitric oxide serum concentration in the rats, when compared with both the M and C diets. The high iron level in the modified diet increased the relative mass of the gonads. The excess iron level in the diet disturbed the zinc, copper, and calcium status of tissues. The decrease in insulin and nitric oxide in rats fed the diet high in iron, fat, fructose, and salt was associated with disorders of zinc, copper, and calcium status, as well as with an increase in the relative mass of the gonads. 相似文献