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981.
Ioannis K Valavanis Stavroula G Mougiakakou Keith A Grimaldi Konstantina S Nikita 《BMC bioinformatics》2010,11(1):453
Background
Obesity is a multifactorial trait, which comprises an independent risk factor for cardiovascular disease (CVD). The aim of the current work is to study the complex etiology beneath obesity and identify genetic variations and/or factors related to nutrition that contribute to its variability. To this end, a set of more than 2300 white subjects who participated in a nutrigenetics study was used. For each subject a total of 63 factors describing genetic variants related to CVD (24 in total), gender, and nutrition (38 in total), e.g. average daily intake in calories and cholesterol, were measured. Each subject was categorized according to body mass index (BMI) as normal (BMI ≤ 25) or overweight (BMI > 25). Two artificial neural network (ANN) based methods were designed and used towards the analysis of the available data. These corresponded to i) a multi-layer feed-forward ANN combined with a parameter decreasing method (PDM-ANN), and ii) a multi-layer feed-forward ANN trained by a hybrid method (GA-ANN) which combines genetic algorithms and the popular back-propagation training algorithm. 相似文献982.
Letta Argyri Ioannis Dafnis Theodossis A. Theodossiou Donald Gantz Efstratios Stratikos Angeliki Chroni 《The Journal of biological chemistry》2014,289(18):12931-12945
The apolipoprotein (apo) E4 isoform has consistently emerged as a susceptibility factor for late-onset Alzheimer disease (AD), although the exact mechanism is not clear. A rare apoE4 mutant, apoE4[L28P] Pittsburgh, burdens carriers with an added risk for late-onset AD and may be a useful tool for gaining insights into the role of apoE4 in disease pathogenesis. Toward this end, we evaluated the effect of the L28P mutation on the structural and functional properties of apoE4. ApoE4[L28P] was found to have significantly perturbed thermodynamic properties, to have reduced helical content, and to expose a larger portion of the hydrophobic surface to the solvent. Furthermore, this mutant is thermodynamically destabilized and more prone to proteolysis. When interacting with lipids, apoE4[L28P] formed populations of lipoprotein particles with structural defects. The structural perturbations brought about by the mutation were accompanied by aberrant functions associated with the pathogenesis of AD. Specifically, apoE4[L28P] promoted the cellular uptake of extracellular amyloid β peptide 42 (Aβ42) by human neuroblastoma SK-N-SH cells as well as by primary mouse neuronal cells and led to increased formation of intracellular reactive oxygen species that persisted for at least 24 h. Furthermore, lipoprotein particles containing apoE4[L28P] induced intracellular reactive oxygen species formation and reduced SK-N-SH cell viability. Overall, our findings suggest that the L28P mutation leads to significant structural and conformational perturbations in apoE4 and can induce functional defects associated with neuronal Aβ42 accumulation and oxidative stress. We propose that these structural and functional changes underlie the observed added risk for AD development in carriers of apoE4[L28P]. 相似文献
983.
Chatzopoulou M Mamadou E Juskova M Koukoulitsa C Nicolaou I Stefek M Demopoulos VJ 《Bioorganic & medicinal chemistry》2011,19(4):1426-1433
Based on our previous work, we studied the effect of methoxy-substitution as well as the regioposition of the benzoyl-moiety of 4a [(1-(3,5-difluoro-4-hydroxyphenyl)-1H-pyrrol-3-yl)(phenyl)methanone]. On this basis, compounds 4b-c and 5a-c were synthesized and assayed for aldose and aldehyde reductase inhibitory activity. Furthermore, a 4,6-difluoro-5-hydroxyphenyl pattern (9) was studied, in order to verify the optimum position of the phenol-moiety. Compound 5b emerged as the most potent and selective inhibitor. Moreover, further assays proved 5b as a potent antioxidant and an inhibitor of sorbitol accumulation in isolated rat lenses. Combining the above attributes, 5b could serve as a lead compound targeted at long-term diabetes complications. 相似文献
984.
985.
The prospective of table olive debittering & washing Effluent (DWE) as feed stock wastewater for anaerobic digestion (AD) systems was investigated in batch and continuous systems together with cattle and pig manures. While DWE considered unsuitable for biological treatment methods due to its unbalanced nature, the co-digestion of the wastewaters resulted in a 50% increase in the methane production/gram volatile solidsadded (CH4/gVSadded), accompanied by 30% phenol reduction and 80% total organic carbon removal (TOC). pH increase during the co-digestion period was not identified as an inhibitory factor and all reactors were able to withstand this operational condition change. Moreover, no volatile fatty acid (VFA) accumulation was observed, indicating that the reactors were not operating under stress-overloading state. Under thermophilic conditions a 7% increase on the TOC removal efficiency was achieved when compared to the mesophilic systems while, under mesophilic conditions phenolic compounds reduction was 10% higher compared to the thermophilic systems. 相似文献
986.
Design, synthesis and antiproliferative activity of novel aminosubstituted benzothiopyranoisoindoles
Christodoulou A Kostakis IK Kourafalos V Pouli N Marakos P Trougakos IP Tsitsilonis OE 《Bioorganic & medicinal chemistry letters》2011,21(10):3110-3112
The synthesis of a number of new benzothiopyrano[4,3,2-cd]isoindole aminoderivatives designed as structural analogues of the key metabolite of the anticancer agent Ledacrine (nitracrine) and their in vitro cytotoxic activity evaluation against HCT-116, MES-SA, and MES-SA/Dx cancer cell lines is reported. The majority of the derivatives possessed noticeable cytotoxicity in a low μM range indicating an interesting structure-activity relationship. 相似文献
987.
Konstantinos Galanopoulos Zaphiris Abas Vassiliki Laga Ioannis Hatziminaoglou Jean Boyazoglu 《Small Ruminant Research》2011,100(1):1-7
Transhumance sheep and goat production have been a common and traditional practice in Greece, with its origins dating back to ancient times. Despite the diminishing number of transhumance farms, it remains an essential activity in less-favoured and mountainous areas of the country. This article applies DEA (Data Envelopment Analysis) in a sample of transhumance farms in Greece in order to assess the technical efficiency of sheep and goat transhumance flocks and determine the factors that affect their performance. The effect of EU subsidies on the technical efficiency of transhumance farms is assessed and the type of farms that benefit most is investigated. Results accrued reveal that the overall technical efficiency of transhumance farms in Greece is quite low and it is affected by herd size. EU subsidies have a significant impact on the technical efficiency of only the low-efficiency, small-sized farms. 相似文献
988.
Radak Z Bori Z Koltai E Fatouros IG Jamurtas AZ Douroudos II Terzis G Nikolaidis MG Chatzinikolaou A Sovatzidis A Kumagai S Naito H Boldogh I 《Free radical biology & medicine》2011,51(2):417-423
8-Oxo-7,8-dihydroguanine (8-oxoG) accumulates in the genome over time and is believed to contribute to the development of aging characteristics of skeletal muscle and various aging-related diseases. Here, we show a significantly increased level of intrahelical 8-oxoG and 8-oxoguanine-DNA glycosylase (OGG1) expression in aged human skeletal muscle compared to that of young individuals. In response to exercise, the 8-oxoG level was lastingly elevated in sedentary young and old subjects, but returned rapidly to preexercise levels in the DNA of physically active individuals independent of age. 8-OxoG levels in DNA were inversely correlated with the abundance of acetylated OGG1 (Ac-OGG1), but not with total OGG1, apurinic/apyrimidinic endonuclease 1 (APE1), or Ac-APE1. The actual Ac-OGG1 level was linked to exercise-induced oxidative stress, as shown by changes in lipid peroxide levels and expression of Cu,Zn-SOD, Mn-SOD, and SIRT3, as well as the balance between acetyltransferase p300/CBP and deacetylase SIRT1, but not SIRT6 expression. Together these data suggest that that acetylated form of OGG1, and not OGG1 itself, correlates inversely with the 8-oxoG level in the DNA of human skeletal muscle, and the Ac-OGG1 level is dependent on adaptive cellular responses to physical activity, but is age independent. 相似文献
989.
990.
Aikaterini Zgouridou Eirini Tripidaki Ioannis A. Giantsis John A. Theodorou Maria Kalaitzidou Dionysios E. Raitsos Athanasios Lattos Apostolia-Maria Mavropoulou Sarantis Sofianos Dimitrios Karagiannis Ilias Chaligiannis Andreas Anestis Nikos Papadakis Konstantinos Feidantsis Dionysia Mintza Alexandra Staikou Basile Michaelidis 《Environmental microbiology》2022,24(3):1012-1034
Global warming affects the aquatic ecosystems, accelerating pathogenic microorganisms' and toxic microalgae's growth and spread in marine habitats, and in bivalve molluscs. New parasite invasions are directly linked to oceanic warming. Consumption of pathogen-infected molluscs impacts human health at different rates, depending, inter alia, on the bacteria taxa. It is therefore necessary to monitor microbiological and chemical contamination of food. Many global cases of poisoning from bivalve consumption can be traced back to Mediterranean regions. This article aims to examine the marine bivalve's infestation rate within the scope of climate change, as well as to evaluate the risk posed by climate change to bivalve welfare and public health. Biological and climatic data literature review was performed from international scientific sources, Greek authorities and State organizations. Focusing on Greek aquaculture and bivalve fisheries, high-risk index pathogenic parasites and microalgae were observed during summer months, particularly in Thermaikos Gulf. Considering the climate models that predict further temperature increases, it seems that marine organisms will be subjected in the long term to higher temperatures. Due to the positive linkage between temperature and microbial load, the marine areas most affected by this phenomenon are characterized as ‘high risk’ for consumer health. 相似文献