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61.
George Pentheroudakis Georgia Raptou Vassiliki Kotoula Ralph M. Wirtz Eleni Vrettou Vasilios Karavasilis Georgia Gourgioti Chryssa Gakou Konstantinos N. Syrigos Evangelos Bournakis Grigorios Rallis Ioannis Varthalitis Eleni Galani Georgios Lazaridis George Papaxoinis Dimitrios Pectasides Gerasimos Aravantinos Thomas Makatsoris Konstantine T. Kalogeras George Fountzilas 《PloS one》2015,10(5)
Background
Although host immune response is an emerging prognostic factor for colorectal cancer, there is no consensus on the optimal methodology, surrogate markers or tissue for study.Patients and Methods
Tumour blocks were prospectively collected from 344 patients with stage II/III colorectal cancer (CRC) treated with adjuvant chemotherapy. Whole section lymphocytic infiltration was studied along with mRNA expression of CD3Z, CD8, CD4, CXCL9, CXCL13, IGHM, FOXP3, SNAI2 and ESR1 by qRT-qPCR in tissue microarray (TMA) cores from the centre of tumour, invasive margin and adjacent normal mucosa.Results
Lymphocytic infiltration, deficient MMR (10.9%), KRAS (40.7%) and BRAF (4.9%) mutations or single mRNA gene expression were not prognostic. Tumour ESR1 gene expression (Hazard Ratio [HR] for relapse 2.33, 95% CI 1.35-4.02; HR for death 1.74, 95% CI 1.02-2.97) and absence of necrosis (HR for relapse 1.71, 95% CI 1.05-2.71; HR for death 1.98, 95% CI 1.14-3.43) were adverse prognostic features. We used CD3Z and CD8 expression in order to devise the mRNA-based Immune Score (mIS) and proceeded to partitioning analysis in 267 patients, with age, stage, tumour site (Right vs Left CRC), KRAS mutation and tumour mIS as input factors. Only in patients with stage III right-sided colon cancer, a low immune response was associated with inferior disease-free survival (mIS-low, HR for relapse 2.28, 95% CI 1.05-8.02). No prognostic significance was seen for tumour mIS in any other stage or site of CRC, or for a similar mIS score derived from adjacent normal mucosa. Independent adverse prognostic significance was retained in multivariable analysis for absence of necrosis, tumour ESR1 expression in all patients and low tumour mIS in stage III right-sided CRC.Conclusions
In localised CRC, mRNA-based CD3Z/CD8 profiling of tumour immune response may have stage, site and tissue-specific prognostic significance, along with ESR1 expression.Trial Registration
ANZCTR.org.au ACTRN12610000509066 相似文献62.
Vasileios Papadopoulos Ioannis Mitroulis Stavros Giaglis 《Molecular biology reports》2010,37(1):355-358
Turkey is one of the few countries in the world where Familial Mediterranean Fever (FMF), an autoinflammatory disease caused
by mutations in MEFV, the gene encoding pyrin, is not rare. Many interesting studies regarding the genetics of Familial Mediterranean Fever in
Turkey have been already published. Despite that different MEFV genetic profiles have been revealed for Turkish FMF patients, deriving from different regions of Turkey, a systematic population
genetics analysis has not been carried out yet. The present study aims to investigate the population genetics of MEFV in Turkish FMF patients so as to additionally facilitate the clinical interpretation of individualized genetic data. All
relevant studies have been recruited by searching PubMed with the terms “MEFV”, “FMF”, and “Turkey”. Seven of them, including
3,061 FMF patients, contained all necessary data concerning allelic and genotypic frequencies of the 4 commonest MEFV mutations in Turkey (M694V, V726A, M680I, E148Q). From all 6,122 MEFV alleles analyzed, the M694V mutation was recognized in 15.6–52.2% (mean 29.3%), the V726A in 1.5–9.7% (mean 4.8%), the M680I
in 1.5–15.5% (mean 7.6%), and the E148Q in 3.2–13.9% (mean 5.5%). Unidentified mutations ranged from 0–42.9% (mean 16.8%).
No mutations were found in 0–54.5% (mean 36.0%) of the patients. The allelic and genotypic frequencies of the most frequent
mutation (M694V) showed aberration of the Hardy–Weinberg law for all 7 populations studied. By application of the Arlequin
2.0 population genetics software, the Fixation index (F
ST) was found to be 0.09994, thus demonstrating that the observed variability is mainly within (90.006%) and not among (9.994%)
populations (P < 0.00001). Moreover, the global test of differentiation demonstrated that every population differs from each other (P < 0.00325). Finally, the Ewens–Watterson test of selective neutrality yielded to statistical significance in only 3 populations.
In conclusion, Turkish FMF patients are characterized by an increased genetic heterogeneity, explained by the intrapopulation
differentiation. Thus, the regional origin should be regarded as a determining factor in the diagnosis of FMF in Turkish patients. 相似文献
63.
Julian Lee Dongseon Lee Hahnbeom Park Evangelos A. Coutsias Chaok Seok 《Proteins》2010,78(16):3428-3436
Protein loops are often involved in important biological functions such as molecular recognition, signal transduction, or enzymatic action. The three dimensional structures of loops can provide essential information for understanding molecular mechanisms behind protein functions. In this article, we develop a novel method for protein loop modeling, where the loop conformations are generated by fragment assembly and analytical loop closure. The fragment assembly method reduces the conformational space drastically, and the analytical loop closure method finds the geometrically consistent loop conformations efficiently. We also derive an analytic formula for the gradient of any analytical function of dihedral angles in the space of closed loops. The gradient can be used to optimize various restraints derived from experiments or databases, for example restraints for preferential interactions between specific residues or for preferred backbone angles. We demonstrate that the current loop modeling method outperforms previous methods that employ residue‐based torsion angle maps or different loop closure strategies when tested on two sets of loop targets of lengths ranging from 4 to 12. Proteins 2010. © 2010 Wiley‐Liss, Inc. 相似文献
64.
Duyck PF Kouloussis NA Papadopoulos NT Quilici S Wang JL Jiang CR Müller HG Carey JR 《Biological journal of the Linnean Society. Linnean Society of London》2010,101(2):345-350
Variation in lifespan may be linked to geographic factors. While latitudinal variation in lifespan has been studied for a number of species, altitude variation has received much less attention, particularly in insects. We measured the lifespan of different populations of the Natal fruit fly Ceratitis rosa along an altitudinal cline. For the different populations we first measured the residual longevity of wild flies by captive cohort approach and compared F(1) generation from the same populations. We showed an increase in lifespan with higher altitude for a part of our data. For the field collected flies (F0) the average remaining lifespan increased monotonically with altitude for males but not for females. For the F(1) generation, longevity of both males and females of the highest-altitude population was longer than for the two other lower-altitude populations. This relationship between altitude and lifespan may be explained by the effects of temperature on reproduction. Reproductive schedules in insects are linked to temperature: lower temperature, characteristic of high-altitude sites, generally slows down reproduction. Because of a strong trade-off between reproduction and longevity, we therefore observed a longer lifespan for the high- altitude populations. Other hypotheses such as different predation rates in the different sites are also discussed. 相似文献
65.
Identification of the major constituents of Hypericum perforatum by LC/SPE/NMR and/or LC/MS 总被引:1,自引:0,他引:1
Tatsis EC Boeren S Exarchou V Troganis AN Vervoort J Gerothanassis IP 《Phytochemistry》2007,68(3):383-393
The newly established hyphenated instrumentation of LC/DAD/SPE/NMR and LC/UV/(ESI)MS techniques have been applied for separation and structure verification of the major known constituents present in Greek Hypericum perforatum extracts. The chromatographic separation was performed on a C18 column. Acetonitrile-water was used as a mobile phase. For the on-line NMR detection, the analytes eluted from column were trapped one by one onto separate SPE cartridges, and hereafter transported into the NMR flow-cell. LC/DAD/SPE/NMR and LC/UV/MS allowed the characterization of constituents of Greek H. perforatum, mainly naphtodianthrones (hypericin, pseudohypericin, protohypericin, protopseudohypericin), phloroglucinols (hyperforin, adhyperforin), flavonoids (quercetin, quercitrin, isoquercitrin, hyperoside, astilbin, miquelianin, I3,II8-biapigenin) and phenolic acids (chlorogenic acid, 3-O-coumaroylquinic acid). Two phloroglucinols (hyperfirin and adhyperfirin) were detected for the first time, which have been previously reported to be precursors in the biosynthesis of hyperforin and adhyperforin. 相似文献
66.
67.
Sacre SM Lundberg AM Andreakos E Taylor C Feldmann M Foxwell BM 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(4):2148-2154
TLR signal via Toll-IL-1R (TIR) homology domain-containing adaptor proteins. One of these adaptors, Toll-IL-1R domain-containing adaptor inducing IFN-beta-related adaptor molecule (TRAM), has been shown to be essential for TLR4 signaling in TRAM(-/-) mice and cell lines. Previously, we showed that MyD88 or Mal dominant-negative constructs did not inhibit LPS induction of cytokines in primary human M-CSF-derived macrophages. A possible explanation was redundancy of the adaptors during LPS signaling. TRAM is a suitable candidate to compensate for these adaptors. To investigate a potential role for TRAM in LPS signaling in human M-CSF-derived macrophages, we engineered an adenoviral construct expressing dominant-negative TRAM-C117H (AdTRAMdn). Synovial fibroblasts (SF) and human umbilical endothelial cells (HUVECs) were used as a nonmyeloid comparison. AdTRAMdn inhibited LPS-induced signaling in SFs and HUVECs, reducing NF-kappaB activation and cytokine production, but did not inhibit LPS signaling in M-CSF-derived human macrophages. Further investigation of other TLR ligands showed that AdTRAMdn was also able to inhibit signaling initiated by lipoteichoic acid, a TLR2 ligand, in SFs and HUVECs and lipoteichoic acid and macrophage-activating lipopeptide 2 signaling was also inhibited in TRAM(-/-) murine embryonic fibroblasts. We conclude that TRAM is an adaptor protein for both TLR4 and TLR2/6 signaling in SFs, HUVECs, and murine embryonic fibroblasts, but cannot demonstrate a role in human macrophages. 相似文献
68.
The protein that binds to DNA base J in trypanosomatids has features of a thymidine hydroxylase 下载免费PDF全文
Yu Z Genest PA ter Riet B Sweeney K DiPaolo C Kieft R Christodoulou E Perrakis A Simmons JM Hausinger RP van Luenen HG Rigden DJ Sabatini R Borst P 《Nucleic acids research》2007,35(7):2107-2115
Trypanosomatids contain an unusual DNA base J (beta-d-glucosylhydroxymethyluracil), which replaces a fraction of thymine in telomeric and other DNA repeats. To determine the function of base J, we have searched for enzymes that catalyze J biosynthesis. We present evidence that a protein that binds to J in DNA, the J-binding protein 1 (JBP1), may also catalyze the first step in J biosynthesis, the conversion of thymine in DNA into hydroxymethyluracil. We show that JBP1 belongs to the family of Fe(2+) and 2-oxoglutarate-dependent dioxygenases and that replacement of conserved residues putatively involved in Fe(2+) and 2-oxoglutarate-binding inactivates the ability of JBP1 to contribute to J synthesis without affecting its ability to bind to J-DNA. We propose that JBP1 is a thymidine hydroxylase responsible for the local amplification of J inserted by JBP2, another putative thymidine hydroxylase. 相似文献
69.
Beatriz A. J. Paranhos Paulo C. D. Mendes Nikos T. Papadopoulos Julio M. M. Walder 《Biocontrol Science and Technology》2007,17(4):375-385
We studied the dispersion patterns of the exotic endoparasitoid, Diachasmimorpha longicaudata (Ahsmed) (Hymenoptera: Braconidae), in 1999 (summer) and in 2000 (winter) in a citrus orchard in southeast Brazil. Different population densities of D. longicaudata were released in the centre of the orchard, and their dispersion was determined by using yellow, sticky, rectangular traps, placed in various distances and heights around the release point. Our results suggest that during summer, climatic conditions did not affect dispersion. However, in winter, dispersion rates were positively affected by temperature, and negatively by rainfall. Both estimated dispersal distance and surface were higher in summer than in winter for all release densities. Dispersion peaked at 2000 parasitoids ha?1 in summer and 8000 parasitoids ha?1 in winter. The importance of our results for the biological control of fruit flies by augmented or innoculative releases of D. longicaudata in southeast Brazil is discussed. 相似文献
70.
Kostomitsopoulos NG Paronis E Alexakos P Balafas E van Loo P Baumans V 《Journal of applied animal welfare science : JAAWS》2007,10(2):111-121
The improvement of housing conditions for mice by using environmental enrichment materials is of high concern for the scientific community. Plastic, autoclavable nest boxes are commercially available and ready to use for specific cases such as in individually ventilated cages, metabolic cages, or during toxicological studies. The aim of this study was to see if the location of the nest box within the cage could influence the mice to prefer and use it. Located on the cage floor or hung from the cage lid, a nest box (MPLEX, Otto Environmental, Milwaukee, Wisconsin), enriched the cages. The study concluded that the location of the nest boxes in the individually ventilated cage plays a significant role in the mice preferring to use it or to avoid it. It is also important to use environmental enrichment items that provide animals with the possibility of expressing their preferences and manipulating them in a way to cope better with their environmental conditions. 相似文献