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101.
Pliatsika P Antoniou A Alexandrou A Panoulis C Kouskouni E Augoulea A Dendrinos S Aravantinos L Creatsa M Lambrinoudaki I 《Gynecological endocrinology : the official journal of the International Society of Gynecological Endocrinology》2012,28(8):655-660
Contradictory results have been reported regarding a relationship between serum lipid levels and bone mineral density. The purpose of this study was to further investigate a possible relationship between those parameters in Greek postmenopausal women. A total of 591 patients followed at a tertiary hospital were examined for seven different lipid factors in relation to dual-emission X-ray absorptiometry measurements at the lumbar spine. Lipoprotein-a was the only lipid measurement that univariately showed an almost significant trend of association with bone mass category (analysis of variance [ANOVA] p value 0.062 for Ln(Lipoprotein-a)). In multiple regression, it was noted that a non-significant negative trend of association of high density lipoprotein (HDL) cholesterol and Apolipoprotein AI with lumbar T-score (p value 0.058 and 0.075, respectively). In age subgroup analysis, Lipoprotein-a and Ln(Lipoprotein-a) presented a negative correlation with lumbar T-score for women with age ≥ 53 years (p value 0.043 and 0.070, respectively), while a negative correlation of HDL and Apolipoprotein AI levels with lumbar T-score remained in women with age < 53 years (p value 0.039 and 0.052, respectively). The findings do not support a strong relationship between lipid levels and bone mass measurements. 相似文献
102.
Christoforou CP Greer CE Challoner BR Charizanos D Ray RP 《Developmental biology》2008,313(2):519-532
Dystrophin and Dystroglycan are the two central components of the multimeric Dystrophin Associated Protein Complex, or DAPC, that is thought to provide a mechanical link between the extracellular matrix and the actin cytoskeleton, disruption of which leads to muscular dystrophy in humans. We present the characterization of the Drosophila ‘crossveinless’ mutation detached (det), and show that the gene encodes the fly ortholog of Dystrophin. Our genetic analysis shows that, in flies, Dystrophin is a non-essential gene, and the sole overt morphological defect associated with null mutations in the locus is the variable loss of the posterior crossvein that has been described for alleles of det. Null mutations in Drosophila Dystroglycan (Dg) are similarly viable and exhibit this crossvein defect, indicating that both of the central DAPC components have been co-opted for this atypical function of the complex. In the developing wing, the Drosophila DAPC affects the intercellular signalling pathways involved in vein specification. In det and Dg mutant wings, the early BMP signalling that initiates crossvein specification is not maintained, particularly in the pro-vein territories adjacent to the longitudinal veins, and this results in the production of a crossvein fragment in the intervein between the two longitudinal veins. Genetic interaction studies suggest that the DAPC may exert this effect indirectly by down-regulating Notch signalling in pro-vein territories, leading to enhanced BMP signalling in the intervein by diffusion of BMP ligands from the longitudinal veins. 相似文献
103.
Vasiliki Kousteni Paraskevi K. Karachle Persefoni Megalofonou 《Marine Biology Research》2017,13(2):161-173
The diet of the small-spotted catshark Scyliorhinus canicula, captured in the Aegean Sea by bottom-trawl from 2006 to 2012, was investigated with respect to sex, maturity condition, sampling location and season. The stomach contents of 432 specimens, measuring from 144 to 517?mm in total length, were analysed. The cumulative prey curve showed that the sample size was adequate to describe the species’ diet, which was quantified using the percentage gravimetric composition (%W). The identified prey items belonged to eight major groups: Teleostei, Chondrichthyes, Crustacea, Cephalopoda, Annelida, Echinodermata, phanerogams and macroalgae, with Teleostei, Crustacea and Cephalopoda being the most consumed in both females (%W?=?48.1, 16.0 and 31.4, respectively) and males (%W?=?33.9, 31.6 and 29.8, respectively). Higher diet diversity was observed in males than females, in immature individuals than mature ones, regardless of sex, as well as in spring in comparison to autumn and winter. Feeding intensity seemed to be influenced mainly by sex and maturity condition. No significant dietary overlap was observed for all possible combinations of the factors examined. Gut indices were compared between the two sexes with females showing statistically significantly higher median relative gut length, as well as a longer gut than males of the same length. Based on the diet composition, S. canicula can be considered a generalist predator consuming, with geographical differentiation, a wide variety of benthic taxa. The estimated fractional trophic level (τ?=?4.22) classified the species as a carnivore with a preference for Teleostei and Cephalopoda, thus confirming its key role in the food web. 相似文献
104.
Papoutsi Z Kassi E Fokialakis N Mitakou S Lambrinidis G Mikros E Moutsatsou P 《Steroids》2007,72(9-10):693-704
Deoxybenzoins are plant compounds with similar structure to isoflavones. In this study, we evaluated the ability of two synthesized deoxybenzoins (compound 1 and compound 2) (a) to influence the activity of the estrogen receptor subtypes ERalpha and ERbeta in HeLa cells co-transfected with an estrogen response element-driven luciferase reporter gene and ERalpha- or ERbeta-expression vectors, (b) to modulate the IGFBP-3 and pS2 protein in MCF-7 breast cancer cells, (c) to induce mineralization of KS483 osteoblasts and (d) to affect the cell viability of endometrial (Ishikawa) and breast (MCF-7, MDA-MB-231) cancer cells. Docking and binding energy calculations were performed using the mixed Monte Carlo/Low Mode search method (Macromodel 6.5). Compound 1 displayed significant estrogenic activity via ERbeta but no activity via ERalpha. Compound 2 was an estrogen-agonist via ERalpha and antagonist via ERbeta. Both compounds increased, like the pure antiestrogen ICI182780, the IGFBP-3 levels. Compound 2 induced, like 17beta-estradiol, significant mineralization in osteoblasts. The cell viability of Ishikawa cells was unchanged in the presence of either compound. Compound 1 increased MCF-7 cell viability consistently with an increase in pS2 levels, whereas compound 2 inhibited the cell viability. Molecular modeling confirmed the agonistic or antagonistic behaviour of compound 2 via ER subtypes. Compound 2, being an agonist in osteoblasts, an antagonist in breast cancer cells, with no estrogenic effects in endometrial cancer cells, makes it a potential selective estrogen receptor modulator and a choice for hormone replacement therapy. 相似文献
105.
The regional variability of sediment bacterial community composition and diversity was studied by comparative analysis of
four large 16S ribosomal DNA (rDNA) clone libraries from sediments in different regions of the Eastern Mediterranean Sea (Thermaikos
Gulf, Cretan Sea, and South lonian Sea). Amplified rDNA restriction analysis of 664 clones from the libraries indicate that
the rDNA richness and evenness was high: for example, a near-1:1 relationship among screened clones and number of unique restriction
patterns when up to 190 clones were screened for each library. Phylogenetic analysis of 207 bacterial 16S rDNA sequences from
the sediment libraries demonstrated that Gamma-, Delta-, and Alphaproteobacteria, Holophaga/Acidobacteria, Planctomycetales,
Actinobacteria, Bacteroidetes, and Verrucomicrobia were represented in all four libraries. A few clones also grouped with
the Betaproteobacteria, Nitrospirae, Spirochaetales, Chlamydiae, Firmicutes, and candidate division OPl 1. The abundance of
sequences affiliated with Gammaproteobacteria was higher in libraries from shallow sediments in the Thermaikos Gulf (30 m)
and the Cretan Sea (100 m) compared to the deeper South Ionian station (2790 m). Most sequences in the four sediment libraries
clustered with uncultured 16S rDNA phylotypes from marine habitats, and many of the closest matches were clones from hydrocarbon
seeps, benzene-mineralizing consortia, sulfate reducers, sulk oxidizers, and ammonia oxidizers. LIBSHUFF statistics of 16S
rDNA gene sequences from the four libraries revealed major differences, indicating either a very high richness in the sediment
bacterial communities or considerable variability in bacterial community composition among regions, or both. 相似文献
106.
Paraskevi N. Polymenakou Nikolaos Lampadariou Manolis Mandalakis Anastasios Tselepides 《Systematic and applied microbiology》2009
This study is the first culture-independent report on the regional variability of bacterial diversity in oxic sediments from the unexplored southern Cretan margin (SCM). Three main deep basins (water column depths: 2670–3603 m), located at the mouth of two submarine canyons (Samaria Gorge and Paximades Channel) and an adjacent slope system, as well as two shallow upper-slope stations (water column depths: 215 and 520 m), were sampled. A total of 454 clones were sequenced and the bacterial richness, estimated through five clone libraries using rarefaction analysis, ranged from 71 to 296 unique phylotypes. The average sequence identity of the retrieved Cretan margin sequences compared to the >1,000,000 known rRNA sequences was only 93.5%. A diverse range of prokaryotes was found in the sediments, which were represented by 15 different taxonomic groups at the phylum level. The phylogenetic analysis revealed that these new sequences grouped with the phyla Acidobacteria, Planctomycetes, Actinobacteria, Gamma-, Alpha- and Delta-proteobacteria. Only a few bacterial clones were affiliated with Chloroflexi, Bacteroidetes, Firmicutes, Gemmatimonadetes, Verrucomicrobia, Nitrospirae, Beta-proteobacteria, Lentisphaerae and Dictyoglomi. A large fraction of the retrieved sequences (12%) did not fall into any taxonomic division previously characterized by molecular criteria, whereas four novel division-level lineages, termed candidate division SCMs, were identified. Bacterial community composition demonstrated significant differences in comparison to previous phylogenetic studies. This divergence was mainly triggered by the dominance of Acidobacteria and Actinobacteria and reflected a bacterial community different from that currently known for oxic and pristine marine sediments. 相似文献
107.
Valasaki K Staikou A Theodorou LG Charamopoulou V Zacharaki P Papamichael EM 《Bioresource technology》2008,99(13):5804-5813
Two thermophilic extracellular proteases, designated Lmm-protease-Lh (29 kDa) and Hmm-protease-Lh (62 kDa), were purified from the Lactobacillus helveticus from kefir, and found active in media containing dithiothreitol; the activity of Lmm-protease-Lh was increased significantly in media containing also EDTAK2. Both novel proteases maintained full activity at 60 °C after 1-h incubation at 10 °C as well as at 80 °C, showing optimum kcat/Km values at pH 7.00 and 60 °C. Only irreversible inhibitors specific for cysteine proteinases strongly inhibited the activity of both novel enzymes, while they remained unaffected by irreversible inhibitors specific for serine proteinases. Both enzymes hydrolyzed the substrate Suc-FR-pNA via Michaelis–Menten kinetics; conversely, the substrate Cbz-FR-pNA was hydrolyzed by Lmm-protease-Lh via Michaelis–Menten kinetics and by Hmm-protease-Lh via substrate inhibition kinetics. Valuable rate constants and activation energies were estimated from the temperature-(kcat/Km) profiles of both enzymes, and useful results were obtained from the effect of different metallic ions on their Michaelis–Menten parameters. 相似文献
108.
Liraglutide,a human glucagon‐like peptide‐1 analogue,stimulates AKT‐dependent survival signalling and inhibits pancreatic β‐cell apoptosis
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109.
Paraskevi Karakosta Aleck H. Alexopoulos 《Computer methods in biomechanics and biomedical engineering》2013,16(5):514-526
A computational model for flow and particle deposition in a three-dimensional representation of the human nasal cavity is developed. Simulations of steady state and dynamic airflow during inhalation are performed at flow rates of 9–60 l/min. Depositions for particles of size 0.5–20 μm are determined and compared with experimental and simulation results from the literature in terms of deposition efficiencies. The nasal model is validated by comparison with experimental and simulation results from the literature for particle deposition under steady-state flow. The distribution of deposited particles in the nasal cavity is presented in terms of an axial deposition distribution as well as a bivariate axial deposition and particle size distribution. Simulations of dynamic airflow and particle deposition during an inhalation cycle are performed for different nasal cavity outlet pressure variations and different particle injections. The total particle deposition efficiency under dynamic flow is found to depend strongly on the dynamics of airflow as well as the type of particle injection. 相似文献
110.
Summary Usual immersion protocols in aldehyde solutions fail to fully preserve the fine structure of both exocarp and mesocarp cells of grape berries, especially for theveraison (onset of ripening) and post-veraison stages. In exocarp cells, fixative diffusion is hampered by the thick polysaccharide cell walls. In mesocarp cells, plasma membrane and tonoplast are disrupted before aldehyde crosslinking occurs, owing to the high osmotic pressure and cell wall texture. The fixative was therefore injected under pressure as small droplets in the outer and inner parts of the fruit, with limited changes in the steady-state organization of fruit tissues. Compared to a selective range of immersion protocols, a striking improvement in cell preservation was observed for all berry tissues, allowing new information on various compartments of grape berry cells. The preservation of organ integrity and local concentration of aldehyde molecules are the most critical parameters of improved fixation. This technique may be applicable to a large array of fleshy fruits containing mainly cells comprising a high volumetric proportion of vacuoles accumulating large amounts of organic acids and sugars and bounded by thick-walled exocarp cells. 相似文献