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排序方式: 共有62条查询结果,搜索用时 19 毫秒
1.
Evita Athanasiou Antonios N. Gargalionis Fotini Boufidou Athanassios Tsakris 《International journal of molecular sciences》2021,22(5)
The role of certain viruses in malignant brain tumor development remains controversial. Experimental data demonstrate that human herpesviruses (HHVs), particularly cytomegalovirus (CMV), Epstein–Barr virus (EBV) and human herpes virus 6 (HHV-6), are implicated in brain tumor pathology, although their direct role has not yet been proven. CMV is present in most gliomas and medulloblastomas and is known to facilitate oncomodulation and/or immunomodulation, thus promoting cancer cell proliferation, invasion, apoptosis, angiogenesis, and immunosuppression. EBV and HHV-6 have also been detected in brain tumors and high-grade gliomas, showing high rates of expression and an inflammatory potential. On the other hand, due to the neurotropic nature of HHVs, novel studies have highlighted the engagement of such viruses in the development of new immunotherapeutic approaches in the context of oncolytic viral treatment and vaccine-based strategies against brain tumors. This review provides a comprehensive evaluation of recent scientific data concerning the emerging dual role of HHVs in malignant brain pathology, either as potential causative agents or as immunotherapeutic tools in the fight against these devastating diseases. 相似文献
2.
Christos L. Chochos Giannis K. Govaris Fotini Kakali Joannis K. Kallitsis Vasilis G. Gregoriou 《Polymer》2005,46(13):4654-4663
New copoly(arylether)s containing substituted terphenyl, quinquephenyl, fluorene and anthracene moieties with aromatic 1,3,4-oxadiazole units were prepared and the resulting copolymers are soluble in common organic solvents. Investigation of their optical properties revealed that they emit blue and yellow light. Moreover, their photovoltaic response was studied in blends with poly(3-hexylthiophene) (P3HT) as the electron donor. Despite the low power conversion efficiencies it was shown that photo-induced electron transfer does take place and the performances are higher than a single layer P3HT device. In addition, an anthracene-fluorene-oxadiazole main chain copolymer (PAFOXD) was also examined in a single layer photovoltaic device and gave one of the highest reported open-circuit voltage (Voc) values in the literature (0.89 V). Finally, a detailed morphological study of the blends and the PAFOXD surface using the atomic force microscopy (AFM) technique, revealed the effect of solvent selection to the preparation of thin films exhibiting the desired performance characteristics. 相似文献
3.
Athena Tsetsekou Fotini Petrakli M. G. Tsoutsouva Dimitris Sioulas 《Journal of the American Ceramic Society》2015,98(8):2366-2372
The processing of nanosized powders to produce dense components is a difficult task, mainly due to the strong agglomeration of nanoparticles. In this work, deagglomeration studies were carried out on sol–gel‐derived γ‐alumina suspensions through the addition of dispersant or dispersant in combination with ethylene glycol as binder and the proper wet ball‐milling. For this purpose, zeta‐potential, viscosity, and sedimentation studies were carried out, whereas dilatometric studies accompanied by XRD analyses were performed on the powders derived from the most stable suspensions. Sintering studies followed and the as received ceramics were evaluated by SEM. The optimum stabilization was achieved through the synergistic addition of 2.75 mg/g ammonium polymethacrylate with 1 wt% ethylene glycol. The respective powder, although it indicates a shift of the sintering start to higher temperature, leads to the densest ceramic with the finest (500 nm mean grain size) and the most homogeneous microstructure. 相似文献
4.
Consumer concern over the quality and safety of conventional food has intensified in recent years, and primarily drives the increasing demand for organically grown food, which is perceived as healthier and safer. Relevant scientific evidence, however, is scarce, while anecdotal reports abound. Although there is an urgent need for information related to health benefits and/or hazards of food products of both origins, generalized conclusions remain tentative in the absence of adequate comparative data. Organic fruits and vegetables can be expected to contain fewer agrochemical residues than conventionally grown alternatives; yet, the significance of this difference is questionable, inasmuch as actual levels of contamination in both types of food are generally well below acceptable limits. Also, some leafy, root, and tuber organic vegetables appear to have lower nitrate content compared with conventional ones, but whether or not dietary nitrate indeed constitutes a threat to human health is a matter of debate. On the other hand, no differences can be identified for environmental contaminants (e.g. cadmium and other heavy metals), which are likely to be present in food from both origins. With respect to other food hazards, such as endogenous plant toxins, biological pesticides and pathogenic microorganisms, available evidence is extremely limited preventing generalized statements. Also, results for mycotoxin contamination in cereal crops are variable and inconclusive; hence, no clear picture emerges. It is difficult, therefore, to weigh the risks, but what should be made clear is that 'organic' does not automatically equal 'safe.' Additional studies in this area of research are warranted. At our present state of knowledge, other factors rather than safety aspects seem to speak in favor of organic food. 相似文献
5.
Mann D.P. Pratt K.F.E. Paraskeva T. Parkin I.P. Williams D.E. 《IEEE sensors journal》2007,7(4):551-556
A novel method of improving the selectivity of metal oxide gas sensors has been developed by using catalytically active molecular sieve materials. They have been successfully introduced into a proprietary sensor array. The cracking patterns of linear alkanes over transition metal exchanged zeolite Y have been measured using a zeolite bed/GC/MS experimental set-up within a temperature range of 300degC to 400degC. Studies have been carried out regarding the effects of metal loading, zeolite type, material fabrication techniques, and operating temperature in relation to catalytic activity and selectivity. The composite sensors utilising the novel zeolite materials have been used in a custom built sensor rig that houses three dual electrode sensors and can measure real-time responses of these sensors to an introduced headspace generated from organic liquids 相似文献
6.
K. Stamatelatou A. Kopsahelis P.S. Blika C.A. Paraskeva G. Lyberatos 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(6):909-917
BACKGROUND: The combined treatment of olive mill wastewater (OMWW) by applying the anaerobic digestion process and further treatment in a system consisting of filters and membranes is presented. The anaerobic digestion of the OMWW took place in a high rate system, the periodic anaerobic baffled reactor (PABR). Application of the membrane system aimed at purifying the anaerobic effluent. RESULTS: An increase in the organic loading rate was achieved by increasing the influent chemical oxygen demand (COD) and alternatively by decreasing the hydraulic retention time (HRT). The first option caused process failure, since the volatile fatty acids accumulation resulted in negligible biogas production. In contrast, the second change (decrease in HRT) led to stable operation that permitted the reduction of the HRT to 3.75 d and increase of the organic loading rate to 8.9 g tCOD L?1 d?1 with satisfactory total COD removal (72%). Higher total COD removal (up to 80%) was observed at lower organic loading rates (<3.5 g tCOD L?1 d?1). Further purification in the membrane units resulted in a final permeate of less than 0.1 g tCOD L?1. The membrane systems proved to be more efficient on the anaerobic effluent than on the raw OMWW (the final permeate in that case contained 1g tCOD L?1). CONCLUSIONS: The anaerobic digestion of OMWW in a PABR was stable even at high organic loading rates. Filtering and membrane fractionation of the PABR effluent resulted in a final permeate stream of high quality, suitable for irrigation and/or reuse in the proposed operating scheme for diluting the OMWW prior to anaerobic digestion. Copyright © 2009 Society of Chemical Industry 相似文献
7.
8.
George TSIRPANLIS Fotini BOUFIDOU Margarita ZOGA George TRIANTAFYLLIS Alexandra FATOUROU Kyriaki STAMATELOU Aliki BLETA Christiana PETRIHOU Stylianos CHATZIPANAGIOTOU Chrysoula NICOLAOU 《Hemodialysis international. International Symposium on Home Hemodialysis》2009,13(2):197-204
Low and not high cholesterol seems to predict high mortality in hemodialysis (HD) patients. The confirmation of this reverse epidemiology as well as its possible interconnection with the increased inflammatory activity observed in this population is being explored in the present study. A group of 136 HD patients was prospectively studied for 2 years, and cardiovascular disease (CVD) as well as all-cause mortality and morbidity were recorded. Baseline lipid profile, inflammatory status, and patients' characteristics were studied as potential survival and hospitalization predictors. During the 24-month follow-up, 21 deaths (52.4% due to CVD) and 38 hospitalizations (55.3% due to CVD) were recorded. In multivariate Cox regression analysis, decreased interleukin-10 (IL-10) and decreased total serum cholesterol (TChol) were the only independent predictors of CVD mortality while C-reactive protein and decreased TChol predicted all-cause mortality. Interleukin-10 at baseline was 11.29 ± 21.49 vs. 5.51 ± 4.57 pg/mL (P<0.018) and TChol 167.37 ± 47.84 vs.122.04 ± 26.48 mg/dL (P<0.000) in survivors vs. nonsurvivors from CVD, while C-reactive protein at baseline was 9.37 ± 11.54 vs. 23.15 ± 18.76 mg/L (P<0.000) and TChol 169.26 ± 46.42 vs. 133.26 ± 46.33 mg/dL (P<0.003) in survivors vs. nonsurvivors from any cause of death. Using the same method of statistical analysis, IL-6 and decreased soluble gp130 (sgp130)—an antagonist of IL-6 action—were found to be the only independent prognostic factors for hospitalization due to CVD while decreased soluble gp130 remained the sole predictor of hospitalization due to any cause. In conclusion, reverse epidemiology regarding cholesterol is confirmed in the present study. Furthermore, inflammatory activity also predicts, independently of or in conjunction with low-cholesterol, CVD and all-cause morbidity and mortality in HD patients. 相似文献
9.
Molecular events including p53 and k-ras alterations in the in vitro progression of a human colorectal adenoma cell line to an adenocarcinoma 总被引:1,自引:0,他引:1
AC Williams SJ Browne WA Yeudal IC Paterson CJ Marshall DP Lane C Paraskeva 《Canadian Metallurgical Quarterly》1993,8(11):3063-3072
The aim of the current study was to identify genetic abnormalities in human colorectal adenoma and carcinoma derived cell lines, and to determine whether the genetic changes which occur in vitro are relevant to the in vivo situation. Loss of 1p(33-35) region was shown to be the most common chromosome 1 abnormality and loss of heterozygosity (LOH) of the DCC gene and/or adjacent sequences was detected in all adenoma derived cells as well as the carcinoma cell lines. The level of p53 protein was also investigated as increased cellular p53 protein had previously been associated with mutation of the p53 gene. A further aim was to investigate genetic changes in our in vitro model of tumour progression, where the adenoma derived PC/AA cell line has previously been converted in vitro to two distinct tumorigenic phenotypes, producing either an adenocarcinoma or a mucinous carcinoma in athymic nude mice. Progression to the adenocarcinoma phenotype was shown to involve a specific chromosome 1 rearrangement, loss of both normal copies of chromosome 18 (although DCC gene sequences were retained), loss of the remaining wild type allele of k-ras resulting in homozygosity for the k-ras codon 12 mutation and increased cellular p53 protein as detected by SDS-PAGE Western blotting. The increase in p53 protein was shown not to be due to the acquisition of a mutation in the p53 gene. Interestingly, progression of the adenoma derived PC/AA cell line to the mucinous malignant phenotype did not involve any of these molecular rearrangements, suggesting that different genetically distinct pathways are involved in colorectal carcinogenesis. These studies show that the genetic changes in our in vitro model of human colorectal tumour progression are similar to those observed in in vivo studies. 相似文献
10.
Evangelia A. Tsapou Fotini Drosou Elisabeth Koussissi Maria Dimopoulou Thalia Dourtoglou Vassilis Dourtoglou 《Journal of food science》2020,85(7):2069-2079
Triggered by the development of lactic acid bacteria (LAB) during the production of Scotch whisky, this study examined the influence of yeast and LAB inoculation on whisky flavor. Four new spirits were produced using the same process. LAB were added as a form of a Greek yogurt's live culture. In each category (barley and rye), one sample was fermented with Greek yogurt while the other was fermented without it. The spirits were matured and analyzed at five different points. Results from gas chromatography-mass spectrometry (GC-MS) analysis showed basic volatile compounds, along with some important extra compounds with yogurt culture. The most obvious differences were observed in the concentration of butanoic acid, a characteristic acid in spirits undergoing lactic acid fermentation: to identify esters such as ethyl butanoate, ethyl isobutanoate, isoamyl butanoate, and 2-phenylethyl butanoate, they are not typical compounds in whisky. 相似文献