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91.
Chidambaram Parameswari Rajasekaran Sripriya Karuppannan Veluthambi 《In vitro cellular & developmental biology. Plant》2010,46(5):395-402
In an analysis of 339 independent T
0 transgenic rice lines generated by Agrobacterium-mediated transformation, albino plants appeared in the T
1 generation in two single-copy transgenic lines, O54 and O36 and in one double-copy transgenic line, C18. While the T
0 plants of these three lines were green, albino and green plants emerged in a 1:3 ratio in the T
1 generation. The albino phenotype segregated as a monogenic recessive trait. Southern blot analysis of the green and albino
plants in the T
1 generation confirmed that the albino trait and the T-DNA insertion events were unlinked. Segregation of the albino trait
from the transgenic trait in the lines O54 and O36 was confirmed in T
2 and T
3 generations, respectively. Homozygous transgenic plants free from the albino trait were also identified. In the double-copy
transgenic line C18, we genetically separated the two transgenic loci, out-segregated the albino locus from both transgene
loci, and identified homozygous plants for each of the transgenic events by Southern blot analysis in the T
1 generation itself. Thus, we demonstrate that when an albino trait appears in the T
1 generation and is unlinked to a transgene locus, the albino locus can be segregated from the transgene locus and homozygous
transgenic lines free from albinos can be established. 相似文献
92.
Robert M. Tynebor Meng-Hsin Chen Swaminathan R. Natarajan Edward A. O’Neill James E. Thompson Catherine E. Fitzgerald Stephen J. O’Keefe James B. Doherty 《Bioorganic & medicinal chemistry letters》2010,20(9):2765-2769
The development and synthesis of potent p38α MAP kinase inhibitors containing a 2H-quinolizin-2-one platform is described. Evolution of the 2H-quinolizin-2-one series from an early lead to solving off target activity and pharmacokinetic issues is also discussed. 相似文献
93.
R. Prasanna A. Sood P. Jaiswal S. Nayak V. Gupta V. Chaudhary M. Joshi C. Natarajan 《Applied Biochemistry and Microbiology》2010,46(2):119-134
Cyanobacteria are a simple, but primitive and diverse group of microorganisms, with characteristics in common to both bacteria and algae. Their success as a group in a wide range of habitats has been attributed to their unique physiological characters and high adaptive ability under a wide range of environmental conditions. The potential of cyanobacteria as a source of a variety of compounds such as polysaccharides, lipids, proteins, vitamins, sterols, enzymes, pharmaceuticals and other fine chemicals is well recognized, and their demand is now on an increasing trend. This compilation reviews the salient advances in the discovery of bioactive compounds from cyanobacteria and their significance in agriculture and industry. 相似文献
94.
Thanemozhi G Natarajan Bhaskar V Kallakury Christine E Sheehan Margaret B Bartlett Natarajan Ganesan Anju Preet Jeffrey S Ross Kevin T FitzGerald 《Cancer cell international》2010,10(1):13
Background
MLL2, an epigenetic regulator in mammalian cells, mediates histone 3 lysine 4 tri-methylation (H3K4me3) through the formation of a multiprotein complex. MLL2 shares a high degree of structural similarity with MLL, which is frequently disrupted in leukemias via chromosomal translocations. However, this structural similarity is not accompanied by functional equivalence. In light of this difference, and previous reports on involvement of epigenetic regulators in malignancies, we investigated MLL2 expression in established cell lines from breast and colon tissues. We then investigated MLL2 in solid tumors of breast and colon by immunohistochemistry, and evaluated potential associations with established clinicopathologic variables. 相似文献95.
Outbred mice traditionally are considered to display high variability, thereby limiting their use in some studies. Researchers frequently are encouraged to use inbred strains of mice because of the greater homogeneity of these experimental animals. We compared the pulmonary inflammatory response of inbred BALB/cJ mice to that of outbred HSD-ICR mice by measuring multiple variables, including cytokines, chemokines, number of pulmonary inflammatory cells, and respiratory parameters. Cockroach allergens induced significant pulmonary inflammation in both BALB and ICR mice. Our comparisons of the coefficients of variance for 148 discrete data sets for each strain or stock indicated that BALB and ICR mice have roughly equivalent intrastrain or -stock variability in our model of asthma-like pulmonary inflammation. The average coefficient of variance, calculated as the ratio of the SD to the mean of a data set, was 0.35 ± 0.34 for BALB mice compared with 0.31 ± 0.32 for ICR mice. In conclusion, inbred BALB and outbred ICR mice have roughly equivalent intrastrain or -stock variability in a murine model of asthma-like pulmonary inflammation. 相似文献
96.
Gene function annotation remains a key challenge in modern biology. This is especially true for high-throughput techniques such as gene expression experiments. Vital information about genes is available electronically from biomedical literature in the form of full texts and abstracts. In addition, various publicly available databases (such as GenBank, Gene Ontology and Entrez) provide access to gene-related information at different levels of biological organization, granularity and data format. This information is being used to assess and interpret the results from high-throughput experiments. To improve keyword extraction for annotational clustering and other types of analyses, we have developed a novel text mining approach, which is based on keywords identified at the level of gene annotation sentences (in particular sentences characterizing biological function) instead of entire abstracts. Further, to improve the expressiveness and usefulness of gene annotation terms, we investigated the combination of sentence-level keywords with terms from the Medical Subject Headings (MeSH) and Gene Ontology (GO) resources. We find that sentence-level keywords combined with MeSH terms outperforms the typical 'baseline' set-up (term frequencies at the level of abstracts) by a significant margin, whereas the addition of GO terms improves matters only marginally. We validated our approach on the basis of a manually annotated corpus of 200 abstracts generated on the basis of 2 cancer categories and 10 genes per category. We applied the method in the context of three sets of differentially expressed genes obtained from pediatric brain tumor samples. This analysis suggests novel interpretations of discovered gene expression patterns. 相似文献
97.
D. Natarajan N. Nagamurugan A. Ramachandran C. Mohanasundari K. Srinivasan 《World journal of microbiology & biotechnology》2007,23(5):719-721
The present work demonstrates the screening of extracts of the rare medicinal herb Euphorbia fusiformis for antifungal activity. The main aim was to investigate its antifungal properties against Candida albicans and Cryptococcus neoformans, the causative agents of human candidiasis and cryptococcosis, respectively. Aqueous and organic solvent extracts from the
leaves and rootstock of the plant were tested against the fungi by the well-in-agar method. Almost all the organic solvent
extracts exhibited an inhibitory effect against C. albicans and to some extent on C. neoformans, except for the aqueous extracts, which had no effect. The combined formulations of the extracts also had better activity
against C. albicans than C. neoformans. This study thus concludes by demonstrating the antifungal properties of E. fusiformis and also the potential research in identifying the active principles, which may have future therapeutic value. 相似文献
98.
Hok S Natarajan A Balhorn R DeNardo SJ DeNardo GL Perkins J 《Bioconjugate chemistry》2007,18(3):912-921
Selective high-affinity ligands (SHALs) were synthesized as molecular targeting agents for HLA-DR10, a cell surface receptor upregulated on malignant B-cell lymphocytes in non-Hodgkin's lymphoma and leukemia. SHALs are designed to mimic the affinity and selectivity of Lym-1, an antibody that binds to the beta-subunit of HLA-DR10. To bind selectively to HLA-DR10, SHALs were constructed to bind to two adjacent pockets on the surface of the beta-subunit of HLA-DR10 located within an epitope recognized by the Lym-1 antibody. A series of multivalent SHALs with molecular masses of 1500-3000 Da were synthesized using solid/polymer-supported synthesis on chlorotrityl chloride resin in 50-80% yield. To enable their use as radionuclide carriers in mouse studies, SHALs were conjugated to DOTA in a solution-phase reaction with 70-100% yield. 57Co/CoCl2 titrations revealed that 50-60% of the DOTA in the DOTA-conjugated SHALs was available for radiometal chelation. These DOTA-SHALs were labeled with 111In and used to carry out pharmacokinetic studies in mice. Radiolabeling reactions of DOTA-SHALs, with exactly one DOTA entity per targeting SHAL molecule, yielded products with greater than 90% radiochemical purity and specific activities ranging from 97 to 150 muCi/mug. 相似文献
99.
Mendes KN Nicorici D Cogdell D Tabus I Yli-Harja O Guerra R Hamilton SR Zhang W 《Journal of proteome research》2007,6(7):2753-2767
Multiple signal transduction pathways play a crucial role in cancer development, progression, and response to different therapies. An important issue is whether common signal transduction pathways are ubiquitously altered in all cancer types and some unique pathways are involved in different cancer types. Another important issue is whether and how transduction signaling molecules are heterogeneously expressed and activated in different cancer cells within and between cancer cell types. METHODS: To gain insight into these issues, we assembled a protein lysate array with 90 different cell lines of 12 different cell types. Each sample is diluted 2-fold six times, and samples from the dilution series were printed three times on the array. We then measured the expression levels and phosphorylation status of 52 different signaling proteins with specific antibodies and carried out statistical hierarchical clustering analysis. RESULTS: The most significant finding based on the cluster analysis was that the cell lines did not group based on tumor types, suggesting that the signaling pathways studied were commonly activated in most of the tumor types cultured in vitro. As expected, related proteins associated with specific signaling pathways clustered together, and analysis of the 30 most differentially expressed proteins revealed the PI3-K signaling pathway was upregulated in several different tumor types and the VEGF-angiogenesis pathway was downregulated in hematopoetic cancers. Another important observation, with clinical implications was that EGFR was the most heterogeneous among all the cell lines. We also observed signaling pathways unique to specific types of cancers such as the inverse relationship between p16ink and Rb, and the EGFR mediated pathway activation characteristic of pancreatic cancers. CONCLUSIONS: Using reverse phase lysate array analysis in this study, we were able to determine potential relationships and signaling pathways, both common and unique, to different types of cancer using cell lines in vitro. This data could be utilized for mining information related to an individual cancer of interest and combined with morphological and genomic profiles would help in creating a combination of expression markers and/or functional signaling maps for specific cancer diagnosis and therapy. 相似文献
100.
Alhazzani Khalid Venkatesan Thiagarajan Natarajan Umamaheswari Algahtani Mohammad Alaseem Ali Alobid Saad Rathinavelu Appu 《Biotechnology letters》2022,44(5-6):787-801
Biotechnology Letters - Colorectal cancer (CRC) is the third most prevalent type of cancer in the United States. The treatment options for cancer include surgery, chemotherapy, radiation,... 相似文献