195 research outputs found
G2 cell cycle arrest and apoptosis are induced in Burkitt's lymphoma cells by the anticancer agent oracin
AbstractThe cytotoxic effect of the new potential intercalating anticancer drug oracin was studied on Burkitt's lymphoma cell line that overexpressed bcl-2 (BL bcl-2) and a control transfectant without the bcl-2 gene (BL SV2). Oracin showed a marked cytostatic effect on both BL SV2 and BL bcl-2 cells. IC50, as measured by the MTT assay, was approx. 5-times greater for BL bcl-2 cells (5.0 μmol/l) than for BL SV2 cells (1.0 μmol/l). There was no significant increase in apoptosis after 24 h of treatment with oracin (1.0 μmol/l) in both cell lines. However, after 48 h from the removal of oracin in BL SV2 culture the levels of apoptotic and secondary necrotic cells increased to 20 and 37%, respectively. In contrast, BL bcl-2 cells treated in a similar manner showed only basal levels of apoptotic and secondary necrotic cells. Analysis of the cell cycle profiles showed a significant increase of S and G2/M phases of the cell cycle in both cell lines after 6 h of drug treatment (1.0 μmol/l). The cells were arrested in G2/M phase of the cell cycle after 24 h, with no significant changes in cell viability. After 72 h, the viable BL SV2 cells were still in G2/M, however, the viability of this culture had fallen to approx. 5%. Flow cytometry analysis of the DNA content revealed the presence of a `sub-G2' region, which represented the apoptotic cells. The BL SV2 cells died after 72 h while they were in the G2/M phase. Although the treated BL bcl-2 cells were similarly arrested in the G2/M phase, they nevertheless remained with a relatively high viability (68%)
The 20th anniversary of EMBnet: 20 years of bioinformatics for the Life Sciences community
The EMBnet Conference 2008, focusing on 'Leading Applications and Technologies in Bioinformatics', was organized by the European Molecular Biology network (EMBnet) to celebrate its 20th anniversary. Since its foundation in 1988, EMBnet has been working to promote collaborative development of bioinformatics services and tools to serve the European community of molecular biology laboratories. This conference was the first meeting organized by the network that was open to the international scientific community outside EMBnet. The conference covered a broad range of research topics in bioinformatics with a main focus on new achievements and trends in emerging technologies supporting genomics, transcriptomics and proteomics analyses such as high-throughput sequencing and data managing, text and data-mining, ontologies and Grid technologies. Papers selected for publication, in this supplement to BMC Bioinformatics, cover a broad range of the topics treated, providing also an overview of the main bioinformatics research fields that the EMBnet community is involved in
Predicting promoters in phage genomes using machine learning models
The renewed interest in phages as antibacterial agents has led to the exponentially growing number of sequenced phage genomes. Therefore, the development of novel bioinformatics methods to automate and facilitate phage genome annotation is of utmost importance. The most difficult step of phage genome annotation is the identification of promoters. As the existing methods for predicting promoters are not well suited for phages, we used machine learning models for locating promoters in phage genomes. Several models were created, using different algorithms and datasets, which consisted of known phage promoter and non-promoter sequences. All models showed good performance, but the ANN model provided better results for the smaller dataset (92% of accuracy, 89% of precision and 87% of recall) and the SVM model returned better results for the larger dataset (93% of accuracy, 91% of precision and 80% of recall). Both models were applied to the genome of Pseudomonas phage phiPsa17 and were able to identify both types of promoters, host and phage, found in phage genomes.This study was supported by the Portuguese Foundation for Science andTechnology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and theProject POCI-01-0145-FEDER-029628. This work was also supported by BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fundunder the scope of Norte2020 - Programa Operacional Regional do Norte.info:eu-repo/semantics/publishedVersio
phiSITE: database of gene regulation in bacteriophages
We have developed phiSITE, database of gene regulation in bacteriophages. To date it contains detailed information about more than 700 experimentally confirmed or predicted regulatory elements (promoters, operators, terminators and attachment sites) from 32 bacteriophages belonging to Siphoviridae, Myoviridae and Podoviridae families. The database is manually curated, the data are collected mainly form scientific papers, cross-referenced with other database resources (EMBL, UniProt, NCBI taxonomy database, NCBI Genome, ICTVdb, PubMed Central) and stored in SQL based database system. The system provides full text search for regulatory elements, graphical visualization of phage genomes and several export options. In addition, visualizations of gene regulatory networks for five phages (Bacillus phage GA-1, Enterobacteria phage lambda, Enterobacteria phage Mu, Enterobacteria phage P2 and Mycoplasma phage P1) have been defined and made available. The phiSITE is accessible at http://www.phisite.org/
The 2010 Nucleic Acids Research Database Issue and online Database Collection: a community of data resources
The current issue of Nucleic Acids Research includes descriptions of 58 new and 73 updated data resources. The accompanying online Database Collection, available at http://www.oxfordjournals.org/nar/database/a/, now lists 1230 carefully selected databases covering various aspects of molecular and cell biology. While most data resource descriptions remain very brief, the issue includes several longer papers that highlight recent significant developments in such databases as Pfam, MetaCyc, UniProt, ELM and PDBe. The databases described in the Database Issue and Database Collection, however, are far more than a distinct set of resources; they form a network of connected data, concepts and shared technology. The full content of the Database Issue is available online at the Nucleic Acids Research web site (http://nar.oxfordjournals.org/)
Precision measurement of charged pion and kaon differential cross sections in electron-positron annihilation at Q = 10.52 GeV
Measurements of inclusive differential cross sections for charged pion and
kaon production in electron-positron annihilation have been carried out at a
center-of-mass energy of Q = 10.52 GeV. The measurements were performed with
the Belle detector at the KEKB electron-positron collider using a data sample
containing 113 million e+e- -> qqbar events, where q={u,d,s,c}. We present
charge-integrated differential cross sections d\sigma_h+-/dz for h+- = pi+-,
K+- as a function of the relative hadron energy z = 2*E_h / sqrt{s} from 0.2 to
0.98. The combined statistical and systematic uncertainties for pi+- (K+-) are
4% (4%) at z ~ 0.6 and 15% (24%) at z ~ 0.9. The cross sections are the first
measurements of the z-dependence of pion and kaon production for z > 0.7 as
well as the first precision cross section measurements at a center-of-mass
energy far below the Z^0 resonance used by the experiments at LEP and SLC.Comment: 7 pages, 3 figures. Ancillary file including all cross section and
uncertainty values with 10 pages, 5 figure
Targeting HIV-1 Env gp140 to LOX-1 Elicits Immune Responses in Rhesus Macaques.
Improved antigenicity against HIV-1 envelope (Env) protein is needed to elicit vaccine-induced protective immunity in humans. Here we describe the first tests in non-human primates (NHPs) of Env gp140 protein fused to a humanized anti-LOX-1 recombinant antibody for delivering Env directly to LOX-1-bearing antigen presenting cells, especially dendritic cells (DC). LOX-1, or 1ectin-like oxidized low-density lipoprotein (LDL) receptor-1, is expressed on various antigen presenting cells and endothelial cells, and is involved in promoting humoral immune responses. The anti-LOX-1 Env gp140 fusion protein was tested for priming immune responses and boosting responses in animals primed with replication competent NYVAC-KC Env gp140 vaccinia virus. Anti-LOX-1 Env gp140 vaccination elicited robust cellular and humoral responses when used for either priming or boosting immunity. Co-administration with Poly ICLC, a TLR3 agonist, was superior to GLA, a TLR4 agonist. Both CD4+ and CD8+ Env-specific T cell responses were elicited by anti-LOX-1 Env gp140, but in particular the CD4+ T cells were multifunctional and directed to multiple epitopes. Serum IgG and IgA antibody responses induced by anti-LOX-1 Env gp140 against various gp140 domains were cross-reactive across HIV-1 clades; however, the sera neutralized only HIV-1 bearing sequences most similar to the clade C 96ZM651 Env gp140 carried by the anti-LOX-1 vehicle. These data, as well as the safety of this protein vaccine, justify further exploration of this DC-targeting vaccine approach for protective immunity against HIV-1
- …