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1.
Elena Bellou Maria Maraki Faidon Magkos Helena Botonaki Demosthenes B. Panagiotakos Stavros A. Kavouras Labros S. Sidossis 《PloS one》2013,8(3)
Background
Acute reduction in dietary energy intake reduces very low-density lipoprotein triglyceride (VLDL-TG) concentration. Although chronic dietary energy surplus and obesity are associated with hypertriglyceridemia, the effect of acute overfeeding on VLDL-TG metabolism is not known.Objective
The aim of the present study was to investigate the effects of acute negative and positive energy balance on VLDL-TG metabolism in healthy women.Design
Ten healthy women (age: 22.0±2.9 years, BMI: 21.2±1.3 kg/m2) underwent a stable isotopically labeled tracer infusion study to determine basal VLDL-TG kinetics after performing, in random order, three experimental trials on the previous day: i) isocaloric feeding (control) ii) hypocaloric feeding with a dietary energy restriction of 2.89±0.42 MJ and iii) hypercaloric feeding with a dietary energy surplus of 2.91±0.32 MJ. The three diets had the same macronutrient composition.Results
Fasting plasma VLDL-TG concentrations decreased by ∼26% after hypocaloric feeding relative to the control trial (P = 0.037), owing to decreased hepatic VLDL-TG secretion rate (by 21%, P = 0.023) and increased VLDL-TG plasma clearance rate (by ∼12%, P = 0.016). Hypercaloric feeding increased plasma glucose concentration (P = 0.042) but had no effect on VLDL-TG concentration and kinetics compared to the control trial.Conclusion
Acute dietary energy deficit (∼3MJ) leads to hypotriglyceridemia via a combination of decreased hepatic VLDL-TG secretion and increased VLDL-TG clearance. On the other hand, acute dietary energy surplus (∼3MJ) does not affect basal VLDL-TG metabolism but disrupts glucose homeostasis in healthy women. 相似文献2.
Xekouki P Nikolakopoulou NM Papageorgiou A Livadas S Voutetakis A Magiakou MA Chrousos GP Spiliotis BE Dacou-Voutetakis C 《Obesity (Silver Spring, Md.)》2007,15(4):860-869
Objective: The aim of our study was to determine the prevalence of impaired glucose tolerance (IGT) and type 2 diabetes (DM2) in obese children and adolescents of Greek origin and compare our data with pertinent literature findings in an attempt to uncover predictive, risk, and preventive factors. Research Methods and Procedures: A total of 117 obese children and adolescents 12.1 ± 2.7 years old underwent a 2‐hour oral glucose tolerance test (OGTT). Insulin resistance (IR) and β‐cell function were estimated using the homeostasis model assessment (HOMA)‐IR and the insulinogenic index, respectively. Results: A total of 17 patients (14.5%) had IGT, and none had DM2. The overall prevalence rates of both IGT and DM2 in our subjects were lower than those reported in a recent multiethnic U.S. study. Nevertheless, the difference between our IGT data and those of the U.S. study was due mostly to the prepubertal subjects (9% vs. 25.4%), whereas no difference was observed in the pubertal population (18% vs. 21%). Fasting glucose, insulin, and HOMA‐IR values were not predictive of IGT. The absolute value of insulin at 2 hours of the OGTT combined with the time‐integrated glycemia (AUCG) can strongly predict IGT, whereas higher area under the curve for insulin (AUCI) values were found to be protective. Discussion: In ethnic groups less prone to diabetes development, IGT or DM2 in obese subjects is more likely to develop at puberty than at the prepubertal stage. It is advisable that physicians caring for obese adolescents perform an OGTT for early detection of IGT because HOMA‐IR values, although higher in IGT subjects and indicative of IR, cannot predict IGT. 相似文献
3.
Nikoleta G. Tsvetanova Roshanak Irannejad Mark von Zastrow 《The Journal of biological chemistry》2015,290(11):6689-6696
Some G protein-coupled receptors (GPCRs), in addition to activating heterotrimeric G proteins in the plasma membrane, appear to elicit a “second wave” of G protein activation after ligand-induced internalization. We briefly summarize evidence supporting this view and then discuss what is presently known about the functional significance of GPCR-G protein activation in endosomes. Endosomal activation can shape the cellular response temporally by prolonging its overall duration, and may shape the response spatially by moving the location of intracellular second messenger production relative to effectors. 相似文献
4.
Anna Makri Stamatia Bellou Maria Birkou Konstantinos Papatrehas Dimitrios Bokas Seraphim Papanikolaou George Aggelis 《Engineering in Life Science》2011,11(1):52-58
Tetraselmis sp. and Nannochloropsis oculata, cultivated in industrial‐scale bioreactors, produced 2.33 and 2.44% w/w lipid (calculated as the sum of fatty acid methyl esters) in dry biomass, respectively. These lipids contained higher amounts of neutral lipids and glycolipids plus sphingolipids, than phospholipids. Lipids of Tetraselmis sp. were characterized by the presence of eicosapentaenoic acid (that was located mainly in phospholipids), and octadecatetraenoic acid (that was equally distributed among lipid fractions), while these fatty acids were completely absent in N. oculata lipids. Additionally, lipids produced by 16 newly isolated strains from Greek aquatic environments (cultivated in flask reactors) were studied. The highest percentage of lipids was found in Prorocentrum triestinum (3.69% w/w) while the lowest in Prymnesium parvum (0.47% w/w). Several strains produced lipids rich in eicosapentaenoic and docosahexaenoic acids. For instance, docosahexaenoic acid was found in high percentages in lipids of Amphidinium sp. S1, P. parvum, Prorocentrum minimum and P. triestinum, while lipids produced by Asterionella sp. (?) S2 contained eicosapentaenoic acid in high concentration. These lipids, containing ω‐3‐long‐chain polyunsaturated fatty acids, have important applications in the food and pharmaceutical industries and in aquaculture. 相似文献
5.
Panagiotis?AnastasiadisEmail author Achilleas?N?Anastasiadis Athanasia?Kotini Nikoleta?Koutlaki Photios?Anninos 《Biomagnetic research and technology》2006,4(1):3
Aim
To elucidate the hemodynamics of the uterine artery myomas by use of Doppler ultrasound and biomagnetic measurements.Method
Twenty-four women were included in the study. Sixteen of them were characterised with large myomas whereas 8 of them with small ones. Biomagnetic signals of uterine arteries myomas were recorded and analyzed with Fourier analysis. The biomagnetic signals were distributed according to spectral amplitudes as high (140–300 ft/√Hz), low (50–110 ft/√Hz) and borderline (111–139 ft/√Hz). Uterine artery waveform measurements were evaluated by use of Pulsatility Index (PI) (normal value PI < 1.45).Results
There was a statistically significant difference between large and small myomas concerning the waveform amplitudes (P < 0.0005) and the PI index (P < 0.0005). Specifically, we noticed high biomagnetic amplitudes in most large myomas (93.75 %) and low biomagnetic amplitudes in most small ones (87.5 %).Conclusion
It is suggested that the biomagnetic recordings of uterine artery myomas could be a valuable modality in the estimation of the circulation of blood cells justifying the findings of Doppler velocimetry examination.6.
7.
Nikoleta Karaiskou Maria Lappa Stefanos Kalomoiris George Oikonomidis Chariklia Psaltopoulou Theodore J. Abatzopoulos Costas Triantaphyllidis Alexander Triantafyllidis 《Conservation Genetics》2011,12(5):1299-1311
The ability to detect genetic differences both in space and time is crucial for conserving genetic variation. It can reveal
genetic diversity and genetic composition changes of declining native populations that are supported through stocking with
captive bred individuals. The present study was designed to analyse the temporal stability of a declining common carp (Cyprinus carpio) population from Lake Volvi (North Greece). Polymorphism was evaluated using seven microsatellite loci at two sampling time
points (separated by 12 years). The genetic variability of four additional populations (from two rivers and two lakes) in
Northern Greece was also investigated for comparison. Heterozygosity values (0.692–0.868) and allelic richness (8.530–11.148)
were high for all studied populations and comparable to other European populations. However, the analysis of temporal common
carp samples from Lake Volvi revealed a significant change in their genetic composition and admixture analysis demonstrated
significant introgression of stocked individuals into the native population. Both temporal and point estimate methods revealed
low effective size (Ne = 61–171.3) for this population, possibly a result of an ancient genetic bottleneck that led to population decline and/or
recent anthropogenic interventions. This low Ne has rendered the native population vulnerable to alteration of its genetic composition. Our study demonstrates that enhancement
programs should be applied cautiously, especially for small populations. Moreover, it underlines the need for temporal analyses,
which may contribute to the evaluation of previous management policies and to future decision making. 相似文献
8.
How does temperature affect splicing events? Isoform switching of splicing factors regulates splicing of LATE ELONGATED HYPOCOTYL (LHY) 下载免费PDF全文
9.
Children with steroid sensitive nephrotic syndrome (SSNS) is thought to have dysregulated type-1/type-2 cytokine network. Interleukin (IL)-18 is a cytokine, which may enhance both type-1 and type-2 responses, depending on the cytokines milieu. This prospective study aimed to assess type-1/type-2 cytokine synthesis and production profile in different stages of SSNS and define the potent involvement of IL-18. Twenty-three children with SSNS, aged 2.5-14 years, were studied; 23/23 both in active stage before treatment initiation and in remission still on steroids; 15/23 in remission off steroids as well. Data were compared with those obtained from 25 age-matched controls. The following parameters were assessed: Basic T cell populations, percentages of CD3+/CD69+/IFN-gamma+ and CD3+/CD69+/IL-4+ T cells as well as serum levels of IFN-gamma, IL-2, IL-4, IL-13 and IL-18. No difference in IL-2 levels was found between nephrotic children of all disease stages and controls (p>0.05). Percentage of CD3+/CD69+/IL-4+ T cells and serum levels of IL-4, IL-13 and IL-18 were significantly higher in the active stage of SSNS compared with the remission stages and controls (p<0.05). On the contrary, percentage of CD3+/CD69+/IFN-gamma+ T cells as well as serum IFN-gamma were significantly lower during active disease stage compared with remission stages and controls (p<0.05). In children with SSNS, of all disease stages, serum levels of IL-18 were significantly correlated with both IL-4 and IL-13 (r=0.628 and p<0.0001, r=0.71 and p<0.0001, respectively). It seems that a type-2 cytokine synthesis and production pattern prevails in children with active SSNS and IL-18 expression is significantly correlated with this type-2 immune response. 相似文献
10.
Stamatia Bellou Mohammed N. Baeshen Ahmed M. Elazzazy Dimitra Aggeli Fotoon Sayegh George Aggelis 《Biotechnology advances》2014
In the last few years, there has been an intense interest in using microalgal lipids in food, chemical and pharmaceutical industries and cosmetology, while a noteworthy research has been performed focusing on all aspects of microalgal lipid production. This includes basic research on the pathways of solar energy conversion and on lipid biosynthesis and catabolism, and applied research dealing with the various biological and technical bottlenecks of the lipid production process. In here, we review the current knowledge in microalgal lipids with respect to their metabolism and various biotechnological applications, and we discuss potential future perspectives. 相似文献