The Experts below are selected from a list of 789567 Experts worldwide ranked by ideXlab platform
Rachel Amir - One of the best experts on this subject based on the ideXlab platform.
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The Expression Level of threonine synthase and cystathionine-γ-synthase is influenced by the Level of both threonine and methionine in Arabidopsis plants
Transgenic Research, 2005Co-Authors: Tal Avraham, Rachel AmirAbstract:The biosynthesis pathways of the essential amino acids methionine and threonine diverge from O -phosphohomoserine, an intermediate metabolite in the aspartate family of amino acids. Thus, the enzymes cystathionine-γ-synthase (CGS) in the methionine pathway and threonine synthase (TS), the last enzyme in the threonine pathway, compete for this common substrate. To study this branching point, we overexpressed TS in sense and antisense orientation in Arabidopsis plants with the aim to study its effect on the Level of threonine but more importantly on the methionine content. Positive correlation was found not only between TS Expression Level and threonine content, but also between TS/threonine and CGS Expression Level. Plants expressing the sense orientation of TS showed a higher Level of threonine, increased Expression Level of CGS, and a significantly higher Level of S -methylmethionine, the transport form of methionine. By contrast, plants expressing the antisense form of TS showed lower Levels of threonine and of CGS Expression Level. In these antisense plants, the methionine Level increased up to 47-fold compared to wild-type plants. To study further the effect of threonine on CGS Expression Level, wild-type plants were irrigated with threonine and control plants were irrigated with methionine or water. While threonine increased the Expression Level of CGS but reduced that of TS, methionine reduced the Expression Level of CGS but increased that of TS. This data demonstrate that both methionine and threonine affect the two enzymes at the branching point, thus controlling not only their own Level, but also the Level of each other. This mechanism probably aids in keeping the Levels of these two essential amino acids sufficiently high to support plant growth.
Paul M. Sharp - One of the best experts on this subject based on the ideXlab platform.
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Predicting Gene Expression Level from Codon Usage Bias
Molecular Biology and Evolution, 2006Co-Authors: Ian Henry, Paul M. SharpAbstract:The "Expression measure" of a gene, E(g), is a statistic devised to predict the Level of gene Expression from codon usage bias. E(g) has been used extensively to analyze prokaryotic genome sequences. We discuss 2 problems with this approach. First, the formulation of E(g) is such that genes with the strongest selected codon usage bias are not likely to have the highest predicted Expression Levels; indeed the correlation between E(g) and Expression Level is weak among moderate to highly expressed genes. Second, in some species, highly expressed genes do not have unusual codon usage, and so codon usage cannot be used to predict Expression Levels. We outline a simple approach, first to check whether a genome shows evidence of selected codon usage bias and then to assess the strength of bias in genes as a guide to their likely Expression Level; we illustrate this with an analysis of Shewanella oneidensis.
Claus Hogdall - One of the best experts on this subject based on the ideXlab platform.
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Expression Level of wilms tumor 1 wt1 protein has limited prognostic value in epithelial ovarian cancer from the danish malova ovarian cancer study
Gynecologic Oncology, 2007Co-Authors: Estrid Hogdall, L Christensen, Susanne K Kjaer, Jan Blaakaer, I J Christensen, Simon A Gayther, Ian Jacobs, Claus HogdallAbstract:Abstract Objectives. To determine the WT1 Expression Level in tumor tissues from 774 women with an epithelial ovarian tumor. Secondly, to evaluate whether WT1 tissue Expression Levels correlate with clinico-pathological parameters and finally to investigate the prognostic value of WT1 Expression Levels in ovarian cancer (OC) patients. Methods. Using tissue array we analyzed the WT1 Expression Level in tissues from 186 women with Low Malignant Potential tumors (LMP) (160 stage I, 5 stage II and 21 stage III) and 560 OC patients (160 stage I, 60 stage II, 289 stage III and 51 stage IV). Results. Using 10% as cut-off Level for WT1 overExpression an overall of 19% LMPs and 17% carcinomas, respectively, were found positive. For both, a higher proportion of positive tumors was found in the serous subtype compared to other histological subtypes ( p Conclusion. In conclusion, based on our analyses we found that WT1 Expression in clinical settings may be of limited prognostic value in Danish OC patients.
Norman E Breslow - One of the best experts on this subject based on the ideXlab platform.
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high telomerase rna Expression Level is an adverse prognostic factor for favorable histology wilms tumor
Journal of Clinical Oncology, 2005Co-Authors: Jeffrey S Dome, Carol A Bockhold, Sierra M Li, Scott D Baker, Daniel M Green, Elizabeth J Perlman, Ashley D Hill, Norman E BreslowAbstract:Purpose A primary objective of the fifth National Wilms Tumor Study (NWTS-5) was to identify prognostic indicators for patients with favorable-histology Wilms' tumor. The prognostic significance of telomerase Expression Level in primary tumor samples was assessed. Patients and Methods A case-cohort study was conducted involving 291 NWTS-5 registrants. Telomerase activity was measured using the telomeric repeat amplification protocol (TRAP). Expression Levels of TERT mRNA (encoding the telomerase catalytic component) and TERC/hTR (the telomerase RNA template) were measured using quantitative real-time polymerase chain reaction. Results After excluding samples because of lack of viable tumor, RNA degradation, or insufficient clinical information, 244 patients remained for the final analysis (96 with relapse and 148 without relapse). Univariate analysis revealed a positive correlation between relative risk (RR) of relapse and Levels of TERT mRNA and TERC Expression. For each doubling in TERT mRNA and TERC le...
Yongqiang Wang - One of the best experts on this subject based on the ideXlab platform.
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The clinical significance of the SIRT2 Expression Level in the early stage of sepsis patients.
Annals of palliative medicine, 2020Co-Authors: Bin Wang, Huihong Zhang, Hongmei Gao, Yongqiang WangAbstract:BACKGROUND Sirtuin2 (SIRT2), one of the members of the sirtuins family, has been proven to be a conserved protein. SIRT2 is reported to be associated with infection and inflammation, and its Expression Level in some cells such as mice brain can be reduced by the stimulation of lipopolysaccharide (LPS). We surmise that the Expression Levels of SIRT2 may be a warning signal of sepsis in the human body. METHODS A total of 38 intensive care units (ICU) patients with a diagnosis of sepsis/septic shock were recruited within 24 h of entry into the ICU. Serum procalcitonin (PCT), hypersensitive C-reactive protein (hs-CRP), and SIRT2 measurements were performed on admission, and on the second and fourth therapy days. The mRNA Expression of SIRT2 was detected by real-time polymerase chain reaction (PCR). RESULTS We ascertained that the Expression Levels of SIRT2 mRNA in sepsis patients and septic shock patients were lower than those in the healthy volunteer control group (P
