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101.
Tasneem Gul Kazi Ghulam Abbas Kandhro Hassan Imran Afridi Naveed Kazi Jameel Ahmed Baig Mohammad Balal Arain Abdul Qadir Shah Nasreen Syed Sham Kumar Nida Fatima Kolachi Sumaira Khan 《Biological trace element research》2010,134(3):265-279
In many developing countries, men and women are at high risk of goiter and iron deficiency. The aim of the recent study is to assess the interaction of (Cu), with iron (Fe), iodine/iodide (I), and thyroid hormones in goitrous patients. Sixty goitrous male (GMPs) and 72 female patients (GFPs) were evaluated for the Cu, Fe, I, and thyroid hormones status in biological samples (serum and urine), and compared to non-goitrous subjects of both genders (M?=?106, F?=?120). The biological samples were analyzed for Cu and Fe concentration using atomic absorption spectrometer, while I was measured by the potentiometric method, prior to microwave-assisted acid digestion (MD). Quality control for the method was established with certified samples. Significantly higher mean values of Cu in serum, and urine samples of GMPs and GFPs, while lower value of Fe and I were observed as compared to control subjects (p?<?0.015), respectively. The mean values of free triiodothyronine (FT3) and free thyroxin (FT4) were found to be lower in goitrous patients of both genders than in the age-matched healthy controls (p?<?0.006 and 0.002), respectively, in contrast high mean values of thyroid-stimulating hormone (TSH) were detected in patients (p?<?0.009), as compared to non-goitrous subjects. It was observed that the deficiencies of Fe, I, and thyroid hormone in goitrous patients could be influenced by efficiency of Cu. 相似文献
102.
Putrescine accumulation confers drought tolerance in transgenic Arabidopsis plants over-expressing the homologous Arginine decarboxylase 2 gene 总被引:1,自引:0,他引:1
103.
104.
Terry Disz Sajia Akhter Daniel Cuevas Robert Olson Ross Overbeek Veronika Vonstein Rick Stevens Robert A Edwards 《BMC bioinformatics》2010,11(1):319
Background
The SEED integrates many publicly available genome sequences into a single resource. The database contains accurate and up-to-date annotations based on the subsystems concept that leverages clustering between genomes and other clues to accurately and efficiently annotate microbial genomes. The backend is used as the foundation for many genome annotation tools, such as the Rapid Annotation using Subsystems Technology (RAST) server for whole genome annotation, the metagenomics RAST server for random community genome annotations, and the annotation clearinghouse for exchanging annotations from different resources. In addition to a web user interface, the SEED also provides Web services based API for programmatic access to the data in the SEED, allowing the development of third-party tools and mash-ups. 相似文献105.
106.
Nina Korzeniewski Rolando Cuevas Anette Duensing Stefan Duensing 《Molecular biology of the cell》2010,21(22):3942-3951
The centrosome is the major microtubule-organizing center of most mammalian cells and consists of a pair of centrioles embedded in pericentriolar material. Before mitosis, the two centrioles duplicate and two new daughter centrioles form adjacent to each preexisting maternal centriole. After initiation of daughter centriole synthesis, the procentrioles elongate in a process that is poorly understood. Here, we show that inhibition of cellular proteolysis by Z-L3VS or MG132 induces abnormal elongation of daughter centrioles to approximately 4 times their normal length. This activity of Z-L3VS or MG132 was found to correlate with inhibition of intracellular protease-mediated substrate cleavage. Using a small interfering RNA screen, we identified a total of nine gene products that either attenuated (seven) or promoted (two) abnormal Z-L3VS–induced daughter centriole elongation. Our hits included known regulators of centriole length, including CPAP and CP110, but, interestingly, several proteins involved in microtubule stability and anchoring as well as centrosome cohesion. This suggests that nonproteasomal functions, specifically inhibition of cellular proteases, may play an important and underappreciated role in the regulation of centriole elongation. They also highlight the complexity of daughter centriole length control and provide a framework for future studies to dissect the molecular details of this process. 相似文献
107.
Cuevas P Díaz-González D García-Martín-Córdova C Sánchez I Lozano RM Giménez-Gallego G Dujovny M 《Journal of cellular and molecular medicine》2006,10(1):225-230
Fibroblast growth factors (FGFs) and their receptors, regularly expressed at high levels in gliomas, are further upregulated during the transition of the tumor from low- to high-grade malignancy, and are essential for glioma progression. FGFs induce upregulation of the mitogen-activated protein kinase (MAPK) signaling cascade in cultured glioma cells, which suggests that MAPK pathway participates in the FGF-dependent glioma development. Recently, it has been shown that dobesilate, an inhibitor of FGF mitogenic activity, shows antiproliferative and proapoptotic activities in glioma cell cultures. Accordingly, it should be expected this new synthetic FGF inhibitor to affect the activation levels of MAPK. Here we report that immunocytochemical and Western blot data unequivocally show that treatment of cell cultures with dobesilate causes a significant decrease of the intracellular levels of ERK1/2 activation, one of the components of the MAPK signalling cascade. This finding supports an important role for dobesilate in glioma growth, suggesting that dobesilate should be a treatment to be born in mind for glioma management. 相似文献
108.
Nadeem N Woodside JV Kelly S Allister R Young IS McEneny J 《The Journal of nutritional biochemistry》2012,23(7):845-851
BackgroundVitamin E and its derivatives, namely, the tocopherols, are known antioxidants, and numerous clinical trials have investigated their role in preventing cardiovascular disease; however, evidence to date remains inconclusive. Much of the in vitro research has focused on tocopherol's effects during low-density lipoprotein (LDL) oxidation, with little attention being paid to very LDL (VLDL) and high-density lipoprotein (HDL). Also, it is now becoming apparent that γ-tocopherol may potentially be more beneficial in relation to cardiovascular health.ObjectivesDo α- and γ-tocopherols become incorporated into VLDL, LDL and HDL and influence their oxidation potential in an in vitro and ex vivo situation?DesignFollowing (i) an in vitro investigation, where plasma was preincubated with increasing concentrations of either α- or γ-tocopherol and (ii) an in vivo 4-week placebo-controlled intervention with α- or γ-tocopherol. Tocopherol incorporation into VLDL, LDL and HDL was measured via high-pressure liquid chromatography, followed by an assessment of their oxidation potential by monitoring conjugated diene formation.ResultsIn vitro: Both tocopherols became incorporated into VLDL, LDL and HDL, which protected VLDL and LDL against oxidation. However and surprisingly, the incorporation into HDL demonstrated pro-oxidant properties. Ex vivo: Both tocopherols were incorporated into all three lipoproteins, protecting VLDL and LDL against oxidation; however, they enhanced the oxidation of HDL.ConclusionsThese results suggest that α- and γ-tocopherols display conflicting oxidant activities dependent on the lipoprotein being oxidized. Their pro-oxidant activity toward HDL may go some way to explain why supplementation studies with vitamin E have not been able to display cardioprotective effects. 相似文献
109.
Dr. Mehmet Beykaya Nida Nur Inkaya Elif Yorulmaz Onder Dr. Yeliz Kasko Arici Prof. Dr. Huseyin Sahin 《化学与生物多样性》2023,20(9):e202300881
This study analysed some physicochemical and quality parameters of 176 royal jelly (RJ) samples from different regions of Türkiye, collected over different years and seasons. According to the obtained results, the moisture percentage varied between 47.36 % and 69.58 %, with no statistically significant differences seen across various seasons and areas (p>0.05). The average value of 10-hydroxy-2-decenoic acid (10-HDA), which varies according to factors such as season, region, and year, was determined to be 2.32 %. It was also seen that this value was close to the international standard. The values of total acidity ranged from 28–58 mL 1 N NaOH/100 g. Furthermore, statistical significance (p<0.001) was observed for the year-region interaction in relation to 10-HDA and total acidity. The pH measurement results for all samples confirmed the acidic nature of the samples and resulted in a range between 3.45 and 3.80. And the pH variability was also found to be statistically significant for years (p=0.002) and regions (p=0.011). Finally, the correlation analysis between moisture (%), 10-HDA (%), total acidity, and pH revealed no statistically significant or strong differences. This comprehensive study, supported by statistical analyses, is thought to be a useful reference for future research on RJ. 相似文献
110.
Rajal Verónica B. Carrillo Leonor Cuevas Carlos M. 《World journal of microbiology & biotechnology》2002,18(7):713-714
A new Penicillium ulaiense strain showed carboxymethylcellulase, pectinase, protease on skim milk and naringinase activities, but no xylanase, cellulase, lipase, amylase, protease on gelatin, and ligninase activities. Studies in liquid medium showed low quantities of pectinases. No mycotoxins were detected. 相似文献