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11.
Ghrelin and obestatin are a single gene products and are a multiple functional peptides that regulates energy homeostasis, and food intake. In the present work, we studied the secretion of ghrelin and its co-secreted peptide obestatin in 44 patients with ischemic heart disease with that of 27 healthy matched controls. Here we first conducted using an immunohistochemistry assay to screen whether human salivary glands have any obestatin immunoreactivity. Then, serum and saliva obestatin and acylated ghrelin levels were determined by using Radioimmunoassay. Our immunohistochemical analysis demonstrated that obestatin was localized in the striated and excretory duct of human salivary gland. We also report for the first time that obestatin, like ghrelin, is present in human salivary gland and saliva. No evidence of the role of obestatin or ghrelin saliva levels in the context of ischemic heart disease was found. Salivary ghrelin and obestatin levels are correlated in controls with the blood levels. Determination of salivary values could represent a non-invasive alternative to serum ones that can be useful in clinical practice.  相似文献   
12.
The utility of Nordmann fir (Abies nordmanniana (Stev.) Spach. Subsp. nordmanniana) leaves from Eastern Black Sea region for the removal (sorption) of metal ions from aqueous solutions was investigated. For this, the optimum values of pH, time, metal concentration, leaf concentration, leaf particle size and adsorption capacity were determined. Also the recovery conditions of the metals from leaves were studied. Cd metal was selected because of its toxic properties. Freundlich isotherm model was used to describe the adsorption behaviour and the experimental results obtained for Cd(2+) adsorption, followed this model well. The utility of Nordmann fir leaves to remove toxic metals from aqueous solutions was proved. Hence, this study showed that the leaves of Nordmann fir can provide cheap source as biosorbents for toxic metal removal from natural or wastewaters.  相似文献   
13.
Although thermophilic members of the genus Bacillus are known to tolerate extreme environmental conditions, they appeared to be readily damaged upon mechanical manipulations. This fact was evidenced in genotyping of some strains of thermophilic Bacillus by pulsed field gel electrophoresis (PFGE). Consequently, a new procedure for the preparation of agarose plugs was developed. The procedure produced interpretable genomic DNA restriction profiles.  相似文献   
14.
Different types of genetic and epigenetic changes are associated with HNSCC. The molecular mechanisms of HNSCC carcinogenesis are still undergoing intensive investigation. WWOX gene expression is altered in many cancers and in a recent work reduced WWOX expression has been associated with miR-134 expression in HNSCC. In this study we investigated the WWOX messenger RNA expression levels in association with the promoter methylation of the WWOX gene and miR-134 expression levels in 80 HNSCC tumor and non-cancerous tissue samples. Our results show that WWOX expression is down-regulated especially in advanced-stage tumor samples or in tumors with SCC. This down-regulation was associated with methylation of the WWOX promoter region but not with miR-134 expression. There was an inverse correlation between the expression level and promoter methylation. We also analyzed whole exons and exon/intron boundries of the WWOX gene by direct sequencing. In our study group we observed 10 different alterations in the coding sequences and 18 different alterations in the non-coding sequences of the WWOX gene in HNSCC tumor samples. These results indicate that the WWOX gene can be functionally inactivated by promoter methylation, epigenetically or by mutations affecting the sequences coding for the enzymatic domain of the gene, functionally. We conclude that inactivation of WWOX gene contributes to the progression of HNSCC.  相似文献   
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16.
The synthesis of tetra- and octa-(7-oxy-3-methyl-4-phenylcoumarin)-substituted indium(III) phthalocyanine complexes obtained from 3-nitrophthalonitrile, 4-nitrophthalonitrile and 4,5-dichlorophthalonitrile substituted with 7-oxy-3-methyl-4-phenylcoumarin are described for the first time in this study. The new compounds have been characterized by elemental analysis, IR, 1H NMR, electronic spectroscopy and mass spectra. The photophysical and photochemical properties of the compounds are also studied in dimethylformamide (DMF). The effects of the number of the substitution and the position on the photophysical and photochemical parameters of the substituted indium(III) phthalocyanine complexes are also reported. Photophysical and photochemical properties of phthalocyanine complexes are very useful for photodynamic therapy (PDT) of cancer applications. In particular, high singlet-oxygen quantum yields are very important for Type II mechanisms. These complexes have good singlet-oxygen quantum yields and show potential as Type II photosensitizers.  相似文献   
17.
Previous studies suggest that endothelial progenitor cells (EPCs) contribute to vascular repair processes. In contrast, circulating microparticles (MPs) are reported to be part of a process that is damaging to vascular cells. Numerous studies suggest that the "balance" between EPCs and MPs is important for the integrity of vascular cells and preservation of endothelial function. In the present study, we assess the impact of acetylsalicylate (ASA) - which is, beside statins and physical exercise, a third basic column in the preventive therapy of coronary artery disease (CAD) - on EPCs and MPs in patients with CAD. We investigated the effect of treatment (8?weeks) with ASA (100?mg/d) on endothelial function (flow-mediated vasodilation, FMD), number of circulating EPCs, and endothelial- and platelet-derived microparticles (eMP, pMP) in 15 male patients (age 59.5?± 12.3?years) with CAD but nonsignificant stenosis. The number of pMPs and eMPs decreased by 62.7% (p?< 0.05) and 28.4% (p?< 0.05), respectively. The number of circulating EPCs (VEGFR2(+)CD34(+)), expressed as ‰ of circulating polymorphonuclear leukocytes, remained unchanged. Despite the reduced number of pMPs and eMPs in response to the ASA therapy, the FMD responses and the maximal dilator effects of nitroglycerin were unaffected. In a control experiment, patients (n = 6) treated with the selective COX-2 inhibitor etoricoxib (90?mg/day) for 8?weeks showed no changes in the number of pMPs, eMPs, and EPCs and in FMD. We report on a novel effect of ASA treatment on the number of circulating endothelial- and platelet-derived microparticles in patients with cardiovascular disease. The mechanism remains elusive, and appears not to be associated with the COX-2 pathway.  相似文献   
18.
Clathrin-mediated endocytosis (CME) regulates many cell physiological processes such as the internalization of growth factors and receptors, entry of pathogens, and synaptic transmission. Within the endocytic network, clathrin functions as a central organizing platform for coated pit assembly and dissociation via its terminal domain (TD). We report the design and synthesis of two compounds named pitstops that selectively block endocytic ligand association with the clathrin TD as confirmed by X-ray crystallography. Pitstop-induced inhibition of clathrin TD function acutely interferes with receptor-mediated endocytosis, entry of HIV, and synaptic vesicle recycling. Endocytosis inhibition is caused by a dramatic increase in the lifetimes of clathrin coat components, including FCHo, clathrin, and dynamin, suggesting that the clathrin TD regulates coated pit dynamics. Pitstops provide new tools to address clathrin function in cell physiology with potential applications as inhibitors of virus and pathogen entry and as modulators of cell signaling.  相似文献   
19.
The therapeutic effects of melatonin or vitamin E plus Se (vE + Se) on the restrain of the heroin withdrawal-induced oxidative stress were studied. For this, rats were divided into ten groups. The rats were injected by fixed or variable doses of heroin for 16 consecutive days, and naloxone was given 1 h after the last heroin injection. One hour after naloxone administration, some groups were treated with melatonin or vE + Se. After 1 h this, blood samples were taken, and the levels of malondialdehyde (MDA) and reduced glutathione (GSH) in whole blood, ascorbic acid, α-tocopherol, retinol, β-carotene, nitrite, nitrate, and ceruloplasmin levels in the serum were measured. Our findings showed that, naloxone administration precipitated the heroin withdrawal. This also increased the level of MDA and decreased the levels of GSH in blood. Melatonin or vE + Se administration prevented the rise in MDA levels and increased the GSH levels. On the other hand, there were some significant differences between α-tocopherol, retinol, β-carotene, nitrite, nitrate, and ceruloplasmin levels of experimental groups. Results of present study showed that heroin withdrawal increased the lipid peroxidation and depressed endogenous antioxidative systems. Additionally, melatonin or vE + Se administrations prevented lipid peroxidation and augmented endogenous antioxidant defense systems.  相似文献   
20.
A feeding trial was carried out to determine the effects of dietary protein and lipid levels on the growth performance and feed utilization of wild‐caught striped sea bream (Lithognathus mormyrus). The experimental fish were collected from a local lagoon (Çardak Lagoon, Çanakkale, Turkey), transferred to the Marine Net Cage Unit and fed by hand to apparent satiation with a commercial sea bream feed (Biomar; 42% crude protein, 16% crude lipid). Approximately 4 weeks were needed to acclimate the fish to farming conditions. No pathological signs were observed and no fish losses occurred during the adaptation period. For the test trials four test diets with different levels of protein and lipid were formulated [low protein and low lipid (LP:LL), low protein and high lipid (LP:HL), high protein and low lipid (HP:LL), and high protein and high lipid (HP:HL)] and fed to L. mormyrus (mean weight 85.0 ± 4.6 g SEM) in the net cages (Ø 2 m, depth 2.5 m) for 60 days. During the experiment water temperature varied between 21.1 and 26.4°C; dissolved oxygen 8.4–9.6 mg L?1; pH 7.2–8.6; and salinity 23.3–25.6‰. Growth performances of fish fed high protein diets were higher compared to fish fed low protein diets, irrespective of the dietary lipid level (P < 0.05). Feed conversion ratio (FCR) and protein efficiency ratio (PER) were not influenced by dietary protein or lipid levels (P > 0.05). Preliminary results indicate that striped sea bream can be easily adapted to farming conditions in net cages, and that a diet containing 50% crude protein and 15% crude lipid (HP:LL) levels with 23.0 g protein MJ?1 gross energy of protein/energy ratio would be suitable for striped sea bream growth.  相似文献   
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