27 research outputs found

    The Cosmological Constant

    Get PDF
    This is a review of the physics and cosmology of the cosmological constant. Focusing on recent developments, I present a pedagogical overview of cosmology in the presence of a cosmological constant, observational constraints on its magnitude, and the physics of a small (and potentially nonzero) vacuum energy.Comment: 50 pages. Submitted to Living Reviews in Relativity (http://www.livingreviews.org/), December 199

    A multiple myeloma classification system that associates normal B-cell subset phenotypes with prognosis.

    Get PDF
    Despite the recent progress in treatment of multiple myeloma (MM), it is still an incurable malignant disease, and we are therefore in need of new risk stratification tools that can help us to understand the disease and optimize therapy. Here we propose a new subtyping of myeloma plasma cells (PCs) from diagnostic samples, assigned by normal B-cell subset associated gene signatures (BAGS). For this purpose, we combined fluorescence-activated cell sorting and gene expression profiles from normal bone marrow (BM) Pre-BI, Pre-BII, immature, naĂŻve, memory, and PC subsets to generate BAGS for assignment of normal BM subtypes in diagnostic samples. The impact of the subtypes was analyzed in 8 available data sets from 1772 patients' myeloma PC samples. The resulting tumor assignments in available clinical data sets exhibited similar BAGS subtype frequencies in 4 cohorts from de novo MM patients across 1296 individual cases. The BAGS subtypes were significantly associated with progression-free and overall survival in a meta-analysis of 916 patients from 3 prospective clinical trials. The major impact was observed within the Pre-BII and memory subtypes, which had a significantly inferior prognosis compared with other subtypes. A multiple Cox proportional hazard analysis documented that BAGS subtypes added significant, independent prognostic information to the translocations and cyclin D classification. BAGS subtype analysis of patient cases identified transcriptional differences, including a number of differentially spliced genes. We identified subtype differences in myeloma at diagnosis, with prognostic impact and predictive potential, supporting an acquired B-cell trait and phenotypic plasticity as a pathogenetic hallmark of MM

    Molecular targeting of prostate cancer cells by a triple drug combination down-regulates integrin driven adhesion processes, delays cell cycle progression and interferes with the cdk-cyclin axis

    Get PDF
    Background: Single drug use has not achieved satisfactory results in the treatment of prostate cancer, despite application of increasingly widespread targeted therapeutics. In the present study, the combined impact of the mammalian target of rapamycin (mTOR)-inhibitor RAD001, the dual EGFr and VGEFr tyrosine kinase inhibitor AEE788 and the histone deacetylase (HDAC)-inhibitor valproic acid (VPA) on prostate cancer growth and adhesion in vitro was investigated. Methods: PC-3, DU-145 and LNCaP cells were treated with RAD001, AEE788 or VPA or with a RAD-AEE-VPA combination. Tumor cell growth, cell cycle progression and cell cycle regulating proteins were then investigated by MTT-assay, flow cytometry and western blotting, respectively. Furthermore, tumor cell adhesion to vascular endothelium or to immobilized extracellular matrix proteins as well as migratory properties of the cells was evaluated, and integrin alpha and beta subtypes were analyzed. Finally, effects of drug treatment on cell signaling pathways were determined. Results: All drugs, separately applied, reduced tumor cell adhesion, migration and growth. A much stronger anti-cancer effect was evoked by the triple drug combination. Particularly, cdk1, 2 and 4 and cyclin B were reduced, whereas p27 was elevated. In addition, simultaneous application of RAD001, AEE788 and VPA altered the membranous, cytoplasmic and gene expression pattern of various integrin alpha and beta subtypes, reduced integrin-linked kinase (ILK) and deactivated focal adhesion kinase (FAK). Signaling analysis revealed that EGFr and the downstream target Akt, as well as p70S6k was distinctly modified in the presence of the drug combination. Conclusions: Simultaneous targeting of several key proteins in prostate cancer cells provides an advantage over targeting a single pathway. Since strong anti-tumor properties became evident with respect to cell growth and adhesion dynamics, the triple drug combination might provide progress in the treatment of advanced prostate cancer

    Coronary plaque burden in Turner syndrome a coronary computed tomography angiography study

    No full text
    Turner syndrome (TS) is associated with coronary artery disease (CAD), an important cause of premature death in TS. However, the determinants of CAD in women with TS remain unknown. In a cross-sectional study design, 168 women without clinical evidence of CAD (115 with TS and 53 without TS) were assessed for the presence and volume of subclinical CAD using coronary CT angiography. Karyotype, the presence of congenital heart defects and conventional cardiovascular risk factors were also registered. Comparative analyses were performed (1) between women with and without TS and (2) in the TS group, between women with and without subclinical CAD. The prevalence of CAD, in crude and adjusted analyses, was not increased for women with TS (crude prevalence: 40 [35%] in TS vs. 25 [47%] in controls, p = 0.12). The volume of atherosclerosis was not higher in women with TS compared with controls (median and interquartile range 0 [0–92] in TS vs. 0 [0–81]mm3 in controls, p = 0.29). Among women with TS, women with subclinical CAD were older (46 ± 13 vs. 37 ± 11 years, p < 0.001), had higher blood pressure (systolic blood pressure 129 ± 16 vs. 121 ± 16 mmHg, p < 0.05) and were more frequently diagnosed with type 2 diabetes (5 [13%] vs. 2 [3%], p < 0.05). Karyotype or congenital heart defects were not associated with subclinical CAD. Some women with TS show early signs of CAD, however overall, not more than women without TS. Conventional cardiovascular risk factors were the principal determinants of CAD also in TS, and CAD prevention strategies should be observed. ClinicalTrial.gov Identifier: NCT01678261 (https://clinicaltrials.gov/ct2/show/NCT01678261)

    Sensor combination and chemometric variable selection for online monitoring of Streptomyces coelicolor fed-batch cultivations

    No full text
    Fed-batch cultivations of Streptomyces coelicolor, producing the antibiotic actinorhodin, were monitored online by multiwavelength fluorescence spectroscopy and off-gas analysis. Partial least squares (PLS), locally weighted regression, and multilinear PLS (N-PLS) models were built for prediction of biomass and substrate (casamino acids) concentrations, respectively. The effect of combination of fluorescence and gas analyzer data as well as of different variable selection methods was investigated. Improved prediction models were obtained by combination of data from the two sensors and by variable selection using a genetic algorithm, interval PLS, and the principal variables method, respectively. A stepwise variable elimination method was applied to the three-way fluorescence data, resulting in simpler and more accurate N-PLS models. The prediction models were validated using leave-one-batch-out cross-validation, and the best models had root mean square error of cross-validation values of 1.02 g l(-1) biomass and 0.8 g l(-1) total amino acids, respectively. The fluorescence data were also explored by parallel factor analysis. The analysis revealed four spectral profiles present in the fluorescence data, three of which were identified as pyridoxine, NAD(P)H, and flavin nucleotides, respectively
    corecore