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421.
Georgiadis AN Papavasiliou EC Lourida ES Alamanos Y Kostara C Tselepis AD Drosos AA 《Arthritis research & therapy》2006,8(3):R82
We investigated lipid profiles and lipoprotein modification after immuno-intervention in patients with early rheumatoid arthritis (ERA). Fifty-eight patients with ERA who met the American College of Rheumatology (ACR) criteria were included in the study. These patients had disease durations of less than one year and had not had prior treatment for it. Smokers or patients suffering from diabetes mellitus, hypothyroidism, liver or kidney disease, Cushing's syndrome, obesity, familiar dyslipidemia and those receiving medications affecting lipid metabolism were excluded from the study. Sixty-three healthy volunteers (controls) were also included. Patients were treated with methotrexate and prednisone. Lipid profiles, disease activity for the 28 joint indices score (DAS-28) as well as ACR 50% response criteria were determined for all patients. The mean DAS-28 at disease onset was 5.8 +/- 0.9. After a year of therapy, 53 (91.3%) patients achieved the ACR 20% response criteria, while 45 (77.6%) attained the ACR 50% criteria. In addition, a significant decrease in the DAS-28, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were observed. ERA patients exhibited higher serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and triglycerides, whereas their serum high-density lipoprotein cholesterol (HDL-C) levels were significantly lower compared to controls. As a consequence, the atherogenic ratio of TC/HDL-C as well as that of LDL-C/HDL-C was significantly higher in ERA patients compared to controls. After treatment, a significant reduction of the atherogenic ratio of TC/HDL-C as well as that of LDL-C/HDL-C was observed, a phenomenon primarily due to the increase of serum HDL-C levels. These changes were inversely correlated with laboratory changes, especially CRP and ESR. In conclusion, ERA patients are characterized by an atherogenic lipid profile, which improves after therapy. Thus, early immuno-intervention to control disease activity may reduce the risk of the atherosclerotic process and cardiovascular events in ERA patients. 相似文献
422.
Papahatjis DP Nahmias VR Andreou T Fan P Makriyannis A 《Bioorganic & medicinal chemistry letters》2006,16(6):1616-1620
The compounds reported in this study are Delta(8)-THC analogues in which the C3 five-carbon linear side chain of Delta(8)-THC was replaced with aryl and 1',1'-cycloalkyl substituents. Of the compounds described here analogues 2d (CB(1), K(i)=11.7 nM. CB(2), K(i)=9.39 nM) and 2f (CB(1), K(i)=8.26 nM. CB(2), K(i)=3.86 nM) exhibited enhanced binding affinities for CB(1) and CB(2), exceeding that of Delta(8)-THC. Efficient procedures for the synthesis of these novel cannabinoid analogues are described. 相似文献
423.
Background
The three-dimensional shape of grain, measured as grain length, width, and thickness (GL, GW, and GT), is one of the most important components of grain appearance in rice. Determining the genetic basis of variations in grain shape could facilitate efficient improvements in grain appearance. In this study, an F7:8 recombinant inbred line population (RIL) derived from a cross between indica and japonica cultivars (Nanyangzhan and Chuan7) contrasting in grain size was used for quantitative trait locus (QTL) mapping. A genetic linkage map was constructed with 164 simple sequence repeat (SSR) markers. The major aim of this study was to detect a QTL for grain shape and to fine map a minor QTL, qGL7.Results
Four QTLs for GL were detected on chromosomes 3 and 7, and 10 QTLs for GW and 9 QTLs for GT were identified on chromosomes 2, 3, 5, 7, 9 and 10, respectively. A total of 28 QTLs were identified, of which several are reported for the first time; four major QTLs and six minor QTLs for grain shape were also commonly detected in both years. The minor QTL, qGL7, exhibited pleiotropic effects on GL, GW, GT, 1000-grain weight (TGW), and spikelets per panicle (SPP) and was further validated in a near isogenic F2 population (NIL-F2). Finally, qGL7 was narrowed down to an interval between InDel marker RID711 and SSR marker RM6389, covering a 258-kb region in the Nipponbare genome, and cosegregated with InDel markers RID710 and RID76.Conclusion
Materials with very different phenotypes were used to develop mapping populations to detect QTLs because of their complex genetic background. Progeny tests proved that the minor QTL, qGL7, could display a single mendelian characteristic. Therefore, we suggested that minor QTLs for traits with high heritability could be isolated using a map-based cloning strategy in a large NIL-F2 population. In addition, combinations of different QTLs produced diverse grain shapes, which provide the ability to breed more varieties of rice to satisfy consumer preferences. 相似文献424.
Yiannikouris A André G Poughon L François J Dussap CG Jeminet G Bertin G Jouany JP 《Biomacromolecules》2006,7(4):1147-1155
In a previous paper we reported that beta-D-glucans isolated from Saccharomyces cerevisiae could adsorb zearalenone, reduce its bioavailability in the digestive tract, and protect animals against its adverse effects. We have now investigated, in vitro, the kinetics of the interaction between other mycotoxins and beta-D-glucans from several sources at three pH values found along the digestive tract (3.0, 6.0, and 8.0). Acid and neutral conditions gave the highest affinity rates for aflatoxins B1 > deoxynivalenol > ochratoxin A and involved both the (1 --> 3)-beta-D-glucans and the (1 --> 6)-beta-D-glucans. Alkaline conditions, owing to their destructuring action on glucans, were favorable only for the adsorption of patulin. Using molecular mechanics, we found that hydroxyl, ketone, and lactone groups are involved in the formation of both hydrogen bonds and van der Waals interactions between aflatoxins B1, deoxynivalenol and patulin, and beta-D-glucans. Differences in the binding capacity of the mycotoxins are due to their specific physical and chemical characteristics. 相似文献
425.
Mokhtar Guerfel Alexandros Beis Tasos Zotos Dalenda Boujnah Mokhtar Zarrouk Angelos Patakas 《Acta Physiologiae Plantarum》2009,31(4):825-831
Differences in abscisic acid (ABA) accumulation between two olive cultivars were studied by enzyme-linked immunosorbent assay
in roots and leaves, leaf water potential (Ψl), stomatal conductance (g
s) as well as photosynthetic rate (A) were also determined in well-watered (WW) and water-stressed (WS) plants of two olive
cultivars ‘Chemlali’ and ‘Chetoui’. ‘Chemlali’ was able to maintain higher leaf CO2 assimilation rate and leaf stomatal conductance throughout the drought cycle when compared with ‘Chetoui’. Furthermore, leaf
water potential of ‘Chemlali’ decreased in lower extent than in Chetoui in response to water deficit. Interestingly, significant
differences in water-stress-induced ABA accumulation were observed between the two olive cultivars and reflect the degree
of stress experienced. Chemlali, a drought tolerant cultivar, accumulated lower levels of ABA in their leaves to regulate
stomatal control in response to water stress compared to the drought sensitive olive cultivar ‘Chetoui’ which accumulated
ABA in large amount. 相似文献
426.
Shalley N. Kudalkar Spyros P. Nikas Philip J. Kingsley Shu Xu James J. Galligan Carol A. Rouzer Surajit Banerjee Lipin Ji Marsha R. Eno Alexandros Makriyannis Lawrence J. Marnett 《The Journal of biological chemistry》2015,290(12):7897-7909
Cyclooxygenase-2 (COX-2) oxygenates arachidonic acid (AA) and the endocannabinoids 2-arachidonoylglycerol (2-AG) and arachidonylethanolamide to prostaglandins, prostaglandin glyceryl esters, and prostaglandin ethanolamides, respectively. A structural homodimer, COX-2 acts as a conformational heterodimer with a catalytic and an allosteric monomer. Prior studies have demonstrated substrate-selective negative allosteric regulation of 2-AG oxygenation. Here we describe AM-8138 (13(S)-methylarachidonic acid), a substrate-selective allosteric potentiator that augments 2-AG oxygenation by up to 3.5-fold with no effect on AA oxygenation. In the crystal structure of an AM-8138·COX-2 complex, AM-8138 adopts a conformation similar to the unproductive conformation of AA in the substrate binding site. Kinetic analysis suggests that binding of AM-8138 to the allosteric monomer of COX-2 increases 2-AG oxygenation by increasing kcat and preventing inhibitory binding of 2-AG. AM-8138 restored the activity of COX-2 mutants that exhibited very poor 2-AG oxygenating activity and increased the activity of COX-1 toward 2-AG. Competition of AM-8138 for the allosteric site prevented the inhibition of COX-2-dependent 2-AG oxygenation by substrate-selective inhibitors and blocked the inhibition of AA or 2-AG oxygenation by nonselective time-dependent inhibitors. AM-8138 selectively enhanced 2-AG oxygenation in intact RAW264.7 macrophage-like cells. Thus, AM-8138 is an important new tool compound for the exploration of allosteric modulation of COX enzymes and their role in endocannabinoid metabolism. 相似文献
427.
Dimitra Vasilaki Athina Bakopoulou Alexandros Tsouknidas Elaine Johnstone Konstantinos Michalakis 《Biophysical reviews》2021,13(3):339
During metastasis, tumor cells need to adapt to their dynamic microenvironment and modify their mechanical properties in response to both chemical and mechanical stimulation. Physical interactions occur between cancer cells and the surrounding matrix including cell movements and cell shape alterations through the process of mechanotransduction. The latter describes the translation of external mechanical cues into intracellular biochemical signaling. Reorganization of both the cytoskeleton and the extracellular matrix (ECM) plays a critical role in these spreading steps. Migrating tumor cells show increased motility in order to cross the tumor microenvironment, migrate through ECM and reach the bloodstream to the metastatic site. There are specific factors affecting these processes, as well as the survival of circulating tumor cells (CTC) in the blood flow until they finally invade the secondary tissue to form metastasis. This review aims to study the mechanisms of metastasis from a biomechanical perspective and investigate cell migration, with a focus on the alterations in the cytoskeleton through this journey and the effect of biologic fluids on metastasis. Understanding of the biophysical mechanisms that promote tumor metastasis may contribute successful therapeutic approaches in the fight against cancer. 相似文献
428.
Alexandros D. Diamantidis Nikos T. Papadopoulos & James R. Carey 《Entomologia Experimentalis et Applicata》2008,128(3):389-397
Insect populations may differ in several life history traits, including behavioural ones such as sexual signalling. We tested whether male Mediterranean fruit fly (medlfy), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), populations obtained from geographically isolated areas exhibit differences in quantitative and qualitative aspects of male sexual signalling. Male sexual signalling was studied in four medfly populations (originating from Brazil, Portugal, Kenya, and Greece) under identical laboratory conditions (25 °C, 60% r.h., and L14:D10). The four populations had been reared for one generation in the laboratory. Sexual signalling was studied in the F1 progeny that were fed one of two diets (yeast hydrolysate plus sugar or sugar only). On both diets, the four populations differed significantly in the progress of maturity (indicated by the average number of males exhibiting sexual signalling) and in the quantity of signalling after attaining maturity. Yeast availability significantly increased sexual signalling; however, it had a different impact on the quantity of signalling in the different populations. A bi-modal pattern of sexual signalling, with one peak at approximately 08:00–09:00 hours and the second at approximately 13:00–14:00 hours, was recorded for all populations and diets. However, quantitative differences among the populations within the 'sexually active' period of the day resulted in significant differences in the daily pattern of sexual signalling. The significance of these findings for understanding adaptations of geographically isolated medfly populations to different ecosystems, as well as its practical importance for the application of the sterile insect technique against C. capitata , is discussed. 相似文献
429.
Benoit Morel Alexey M Kozlov Alexandros Stamatakis Gergely J Szllsi 《Molecular biology and evolution》2020,37(9):2763
Inferring phylogenetic trees for individual homologous gene families is difficult because alignments are often too short, and thus contain insufficient signal, while substitution models inevitably fail to capture the complexity of the evolutionary processes. To overcome these challenges, species-tree-aware methods also leverage information from a putative species tree. However, only few methods are available that implement a full likelihood framework or account for horizontal gene transfers. Furthermore, these methods often require expensive data preprocessing (e.g., computing bootstrap trees) and rely on approximations and heuristics that limit the degree of tree space exploration. Here, we present GeneRax, the first maximum likelihood species-tree-aware phylogenetic inference software. It simultaneously accounts for substitutions at the sequence level as well as gene level events, such as duplication, transfer, and loss relying on established maximum likelihood optimization algorithms. GeneRax can infer rooted phylogenetic trees for multiple gene families, directly from the per-gene sequence alignments and a rooted, yet undated, species tree. We show that compared with competing tools, on simulated data GeneRax infers trees that are the closest to the true tree in 90% of the simulations in terms of relative Robinson–Foulds distance. On empirical data sets, GeneRax is the fastest among all tested methods when starting from aligned sequences, and it infers trees with the highest likelihood score, based on our model. GeneRax completed tree inferences and reconciliations for 1,099 Cyanobacteria families in 8 min on 512 CPU cores. Thus, its parallelization scheme enables large-scale analyses. GeneRax is available under GNU GPL at https://github.com/BenoitMorel/GeneRax (last accessed June 17, 2020). 相似文献
430.
A two-stage lab-scale UASB reactor, incorporating a selector-type UASB prior to the main reactor was operated at 37 °C with
an easily biodegradable food wastewater having a COD of 3,000 mg/L. Varying the hydraulic retention time from 25 to 5 h, the
removal of COD by the two-stage process was higher than 95%. Effluent soluble COD was consistently below 75 mg/L and the methane
production rate close to theoretical values. The selector UASB removed the majority of the organic load (70–90%) at high organic
loading rate, i.e. between 6 and 30 g/(Ld) and the granular sludge developed was characterized by dense microbial colonies,
high volatile suspended solids’ content and high substrate degradation efficiency. Design of a two-stage process, incorporating
a selector and a second UASB reactor, was able to achieve stable and complete substrate degradation at overall loading rates
of the order of ~10–15 g/(Ld). 相似文献