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71.
Tian L Cai T Pfeffer MA Piankov N Cremieux PY Wei LJ 《Biostatistics (Oxford, England)》2009,10(2):275-281
Recently, meta-analysis has been widely utilized to combine information across comparative clinical studies for evaluating drug efficacy or safety profile. When dealing with rather rare events, a substantial proportion of studies may not have any events of interest. Conventional methods either exclude such studies or add an arbitrary positive value to each cell of the corresponding 2 x 2 tables in the analysis. In this article, we present a simple, effective procedure to make valid inferences about the parameter of interest with all available data without artificial continuity corrections. We then use the procedure to analyze the data from 48 comparative trials involving rosiglitazone with respect to its possible cardiovascular toxicity. 相似文献
72.
Huber S Uhlemann A Gamper N Duranton C Lang F Kremsner P 《Trends in parasitology》2002,18(8):346; author reply 346-346; author reply 347
73.
Khachik F Carvalho L Bernstein PS Muir GJ Zhao DY Katz NB 《Experimental biology and medicine (Maywood, N.J.)》2002,227(10):845-851
Recent epidemiological studies have suggested that the consumption of tomatoes and tomato-based food products reduce the risk of prostate cancer in humans. This protective effect has been attributed to carotenoids, which are one of the major classes of phytochemicals in this fruit. The most abundant carotenoid in tomato is lycopene, followed by phytoene, phytofluene, zeta-carotene, gamma-carotene, beta-carotene, neurosporene, and lutein. The distribution of lycopene and related carotenoids in tomatoes and tomato-based food products has been determined by extraction and high-performance liquid chromatography-UV/Visible photodiode array detection. Detailed qualitative and quantitative analysis of human serum, milk, and organs, particularly prostate, have revealed the presence of all the aforementioned carotenoids in biologically significant concentrations. Two oxidative metabolites of lycopene, 2,6-cyclolycopene-1,5-diols A and B, which are only present in tomatoes in extremely low concentrations, have been isolated and identified in human serum, milk, organs (liver, lung, breast, liver, prostate, colon) and skin. Carotenoids may also play an important role in the prevention of age-related macular degeneration, cataracts, and other blinding disorders. Among 25 dietary carotenoids and nine metabolites routinely found in human serum, mainly (3R,3'R,6'R)-lutein, (3R,3'R)-zeaxanthin, lycopene, and their metabolites were detected in ocular tissues. In this review we identified and quantified the complete spectrum of carotenoids from pooled human retinal pigment epithelium, ciliary body, iris, lens, and in the uveal tract and in other tissues of the human eye to gain a better insight into the metabolic pathways of ocular carotenoids. Although (3R,3'R,6'R)-lutein, (3R,3'R)-zeaxanthin, and their metabolites constitute the major carotenoids in human ocular tissues, lycopene and a wide range of dietary carotenoids have been detected in high concentrations in ciliary body and retinal pigment epithelium. The possible role of lycopene and other dietary carotenoids in the prevention of age-related macular degeneration and other eye diseases is discussed. 相似文献
74.
Vitalii Zemlianskii Ksenia Ermokhina Gabriela Schaepman-Strub Nadezhda Matveyeva Elena Troeva Igor Lavrinenko Mikhail Telyatnikov Igor Pospelov Natalia Koroleva Nadezhda Leonova Olga Khitun Donald Walker Amy Breen Nikita Kadetov Olga Lavrinenko Tatiana Ivleva Sergey Kholod Nataliia Petrzhik Yakov Gunin Maria Kurysheva Anna Lapina Denis Korolev Ekaterina Kudr Elena Plekhanova 《Global Ecology and Biogeography》2023,32(10):1699-1706
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76.
Dipali Rahane Tannu Dhingra Guruswami Chalavady Aishika Datta Bijoyani Ghosh Nikita Rana Anupom Borah Shailendra Saraf Pallab Bhattacharya 《Cell biochemistry and function》2024,42(2):e3940
Eukaryotic cells utilize oxygen for different functions of cell organelles owing to cellular survival. A balanced oxygen homeostasis is an essential requirement to maintain the regulation of normal cellular systems. Any changes in the oxygen level are stressful and can alter the expression of different homeostasis regulatory genes and proteins. Lack of oxygen or hypoxia results in oxidative stress and formation of hypoxia inducible factors (HIF) and reactive oxygen species (ROS). Substantial cellular damages due to hypoxia have been reported to play a major role in various pathological conditions. There are different studies which demonstrated that the functions of cellular system are disrupted by hypoxia. Currently, study on cellular effects following hypoxia is an important field of research as it not only helps to decipher different signaling pathway modulation, but also helps to explore novel therapeutic strategies. On the basis of the beneficial effect of hypoxia preconditioning of cellular organelles, many therapeutic investigations are ongoing as a promising disease management strategy in near future. Hence, the present review discusses about the effects of hypoxia on different cellular organelles, mechanisms and their involvement in the progression of different diseases. 相似文献
77.
Hattan SJ Marchese J Khainovski N Martin S Juhasz P 《Journal of proteome research》2005,4(6):1931-1941
Large-scale proteomic analyses frequently rely on high-resolution peptide separation of digested protein mixtures in multiple dimensions to achieve accuracy in sample detection and sensitivity in dynamic range of coverage. This study was undertaken to demonstrate the feasibility of MALDI MS/MS with off-line coupling to HPLC for the analysis of whole cell lysates of wild-type yeast by three different workflows: SCX-RPHPLC-MS/MS, high-pH SAX-RPHPLC-MS/MS and RP (protein)-SCX-RPHPLC-MS/MS. The purpose of these experiments was to demonstrate the effect of a workflow on the end results in terms of the number of proteins detected, the average peptide coverage of proteins, and the number of redundant peptide sequencing attempts. Using 60 microg of yeast lysate, minor differences were seen in the number of proteins detected by each method (800-1200). The most significant differences were observed in redundancy of MS/MS acquisitions. 相似文献
78.
Lior Shamir Nikita Orlov D Mark Eckley Tomasz Macura Josiah Johnston Ilya G Goldberg 《Source code for biology and medicine》2008,3(1):13
Background
Biological imaging is an emerging field, covering a wide range of applications in biological and clinical research. However, while machinery for automated experimenting and data acquisition has been developing rapidly in the past years, automated image analysis often introduces a bottleneck in high content screening. 相似文献79.
Anil Kumar Nalini Chandran Nikita Bhatnagar Bumki Kim Ki-Hong Jung 《Journal of Plant Biology》2016,59(6):639-647
Molecular understanding of morphological agronomic traits is very important to improve grain yield and quality. According to the literature information summarized in Overview of Functionally Characterized Genes in Rice online database, 430 genes related to these traits have been functionally characterized in rice, while the functions of other genes remain to be elucidated. Gene indexed mutants are available for at least half of the genes identified in the rice genome, and are very useful resources to study gene function. To suggest candidate genes for functional studies associated with morphological agronomic traits, we identified genes with tissue/organ-preferred expression patterns through meta-analysis of microarray data, and identified 781 genes for roots, 1,084 for leaves, 1,029 for calluses, 927 for anthers, 241 for embryos, and 343 for endosperms. Additionally, 4,243 genes expressed in all tissue types were allocated to a ubiquitously-expressed gene group (‘housekeeping’ genes). The estimated tissue/organ-preferred and housekeeping genes accounted for 40% of the characterized genes associated with morphological agronomic traits, indicating that identification of tissue/organ-preferred genes is an effective way to provide putative gene function. In this study, we reported the information of gene-indexed mutants for 84% of the identified candidate genes. Our candidate genes and relating indexed mutant resources can potentially be used to improve morphological agronomic traits in rice. 相似文献
80.
Dmitri Rozanov Anton Cheltsov Eduard Sergienko Stefan Vasile Vladislav Golubkov Alexander E. Aleshin Trevor Levin Elie Traer Byron Hann Julia Freimuth Nikita Alexeev Max A. Alekseyev Sergey P Budko Hans Peter B?chinger Paul Spellman 《PloS one》2015,10(6)
A high throughput screen for compounds that induce TRAIL-mediated apoptosis identified ML100 as an active chemical probe, which potentiated TRAIL activity in prostate carcinoma PPC-1 and melanoma MDA-MB-435 cells. Follow-up in silico modeling and profiling in cell-based assays allowed us to identify NSC130362, pharmacophore analog of ML100 that induced 65-95% cytotoxicity in cancer cells and did not affect the viability of human primary hepatocytes. In agreement with the activation of the apoptotic pathway, both ML100 and NSC130362 synergistically with TRAIL induced caspase-3/7 activity in MDA-MB-435 cells. Subsequent affinity chromatography and inhibition studies convincingly demonstrated that glutathione reductase (GSR), a key component of the oxidative stress response, is a target of NSC130362. In accordance with the role of GSR in the TRAIL pathway, GSR gene silencing potentiated TRAIL activity in MDA-MB-435 cells but not in human hepatocytes. Inhibition of GSR activity resulted in the induction of oxidative stress, as was evidenced by an increase in intracellular reactive oxygen species (ROS) and peroxidation of mitochondrial membrane after NSC130362 treatment in MDA-MB-435 cells but not in human hepatocytes. The antioxidant reduced glutathione (GSH) fully protected MDA-MB-435 cells from cell lysis induced by NSC130362 and TRAIL, thereby further confirming the interplay between GSR and TRAIL. As a consequence of activation of oxidative stress, combined treatment of different oxidative stress inducers and NSC130362 promoted cell death in a variety of cancer cells but not in hepatocytes in cell-based assays and in in vivo, in a mouse tumor xenograft model. 相似文献