379 research outputs found

    Combined experimental and computational analysis of DNA damage signaling reveals context-dependent roles for Erk in apoptosis and G1/S arrest after genotoxic stress

    Get PDF
    Data-driven modeling was used to analyze the complex signaling dynamics that connect DNA repair with cell survival, cell-cycle arrest, or apoptosis. This analysis revealed an unexpected role for Erk in G1/S arrest and apoptotic cell death following doxorubicin-induced DNA damage

    Regulation of pituitary MT1 melatonin receptor expression by gonadotrophin-releasing hormone (GnRH) and early growth response factor-1 (Egr-1) : in vivo and in vitro studies

    Get PDF
    Copyright: © 2014 Bae et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Funding: This work was funded by the UK Biotechnology and Biological Sciences Research Council (BBSRC; grant BB/F020309/1; http://www.bbsrc.ac.uk/home/home.aspx). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

    Cost-effectiveness of total neoadjuvant therapy with short-course radiotherapy for resectable locally advanced rectal cancer

    Get PDF
    Importance: Short-course radiotherapy and total neoadjuvant therapy (SCRT-TNT) followed by total mesorectal excision (TME) has emerged as a new treatment paradigm for patients with locally advanced rectal adenocarcinoma. However, the economic implication of this treatment strategy has not been compared with that of conventional long-course chemoradiotherapy (LCCRT) followed by TME with adjuvant chemotherapy. Objective: To perform a cost-effectiveness analysis of SCRT-TNT vs LCCRT in conjunction with TME for patients with locally advanced rectal cancer. Design, Setting, and Participants: A decision analytical model with a 5-year time horizon was constructed for patients with biopsy-proven, newly diagnosed, primary locally advanced rectal adenocarcinoma treated with SCRT-TNT or LCCRT. Markov modeling was used to model disease progression and patient survival after treatment in 3-month cycles. Data on probabilities and utilities were extracted from the literature. Costs were evaluated from the Medicare payer\u27s perspective in 2020 US dollars. Sensitivity analyses were performed for key variables. Data were collected from October 3, 2020, to January 20, 2021, and analyzed from November 15, 2020, to April 25, 2021. Exposures: Two treatment strategies, SCRT-TNT vs LCCRT with adjuvant chemotherapy, were compared. Main Outcomes and Measures: Cost-effectiveness was evaluated using the incremental cost-effectiveness ratio and net monetary benefits. Effectiveness was defined as quality-adjusted life-years (QALYs). Both costs and QALYs were discounted at 3% annually. Willingness-to-pay threshold was set at 50 000/QALY.Results:Duringthe5−yearhorizon,thetotalcostwas50 000/QALY. Results: During the 5-year horizon, the total cost was 41 355 and QALYs were 2.21 for SCRT-TNT; for LCCRT, the total cost was 54 827andQALYswere2.12,resultinginanegativeincrementalcost−effectivenessratio(−54 827 and QALYs were 2.12, resulting in a negative incremental cost-effectiveness ratio (-141 256.77). The net monetary benefit was 69 300forSCRT−TNTand69 300 for SCRT-TNT and 51 060 for LCCRT. Sensitivity analyses using willingness to pay at 100 000/QALYand100 000/QALY and 150 000/QALY demonstrated the same conclusion. Conclusions and Relevance: These findings suggest that SCRT-TNT followed by TME incurs lower cost and improved QALYs compared with conventional LCCRT followed by TME and adjuvant chemotherapy. These data offer further rationale to support SCRT-TNT as a novel cost-saving treatment paradigm in the management of locally advanced rectal cancer

    Ecological conditions determine extinction risk in co-evolving bacteria-phage populations.

    Get PDF
    BACKGROUND: Antagonistic coevolution between bacteria and their viral parasites, phage, drives continual evolution of resistance and infectivity traits through recurrent cycles of adaptation and counter-adaptation. Both partners are vulnerable to extinction through failure of adaptation. Environmental conditions may impose unequal abiotic selection pressures on each partner, destabilising the coevolutionary relationship and increasing the extinction risk of one partner. In this study we explore how the degree of population mixing and resource supply affect coevolution-induced extinction risk by coevolving replicate populations of Pseudomonas fluorescens SBW25 with its associated lytic phage SBW25Đ€2 under four treatment regimens incorporating low and high resource availability with mixed or static growth conditions. RESULTS: We observed an increased risk of phage extinction under population mixing, and in low resource conditions. High levels of evolved bacterial resistance promoted phage extinction at low resources under both mixed and static conditions, whereas phage populations could survive when phage susceptible bacterial genotypes rose to high frequency. CONCLUSIONS: These findings demonstrate that phage extinction risk is influenced by multiple abiotic conditions, which together act to destabilise the bacteria-phage coevolutionary relationship. The risk of coevolution-induced extinction is therefore dependent on the ecological context

    A New Vaccine for Tuberculosis: The Challenges of Development and Deployment

    Get PDF
    Tuberculosis (TB) is one of the world’s leading causes of death due to infection and efforts to control TB would be substantially aided by the availability of an improved TB vaccine. There are currently nine new TB vaccines in clinical development, and the first efficacy trials are due to commence in 2009. There are many complex ethical issues which arise at all stages of TB vaccine development, from the need to conduct trials in developing countries to informed consent and the process of ethical review. While it is important that these issues are discussed, it may also be timely to consider the challenges which may arise if a vaccine in clinical development proves to be highly effective. We examine a number of scenarios where decisions on the deployment of a new TB vaccine may impact on the rights and liberty of the individual

    Lack of association between the chemokine receptor 5 polymorphism CCR5delta32 in rheumatoid arthritis and juvenile idiopathic arthritis

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The chemokine receptor CCR5 has been detected at elevated levels on synovial T cells, and a 32 bp deletion in the <it>CCR5 </it>gene leads to a non-functional receptor. A negative association between the <it>CCR5Δ32 </it>and rheumatoid arthritis (RA) has been reported, although with conflicting results. In juvenile idiopathic arthritis (JIA), an association with CCR5 was recently reported. The purpose of this study was to investigate if the <it>CCR5Δ32 </it>polymorphism is associated with RA or JIA in Norwegian cohorts.</p> <p>Methods</p> <p>853 RA patients, 524 JIA patients and 658 controls were genotyped for the <it>CCR5Δ32 </it>polymorphism.</p> <p>Results</p> <p>The <it>CCR5Δ32 </it>allele frequency was 11.5% in the controls vs. 10.4% in RA patients (OR = 0.90; <it>P </it>= 0.36) and 9.7% in JIA patients (OR = 0.85; <it>P </it>= 0.20). No decreased homozygosity was observed for <it>CCR5Δ32</it>, as previously suggested.</p> <p>Conclusion</p> <p>Our data do not support an association between the <it>CCR5Δ32 </it>allele and Norwegian RA or JIA patients. Combining our results with those from a recently published meta-analysis still provide evidence for a role for <it>CCR5Δ32 </it>in RA, albeit substantially weaker than the effect first reported.</p

    Trypacidin, a Spore-Borne Toxin from Aspergillus fumigatus, Is Cytotoxic to Lung Cells

    Get PDF
    Inhalation of Aspergillus fumigatus conidia can cause severe aspergillosis in immunosuppressed people. A. fumigatus produces a large number of secondary metabolites, some of which are airborne by conidia and whose toxicity to the respiratory tract has not been investigated. We found that spores of A. fumigatus contain five main compounds, tryptoquivaline F, fumiquinazoline C, questin, monomethylsulochrin and trypacidin. Fractionation of culture extracts using RP-HPLC and LC-MS showed that samples containing questin, monomethylsulochrin and trypacidin were toxic to the human A549 lung cell line. These compounds were purified and their structure verified using NMR in order to compare their toxicity against A549 cells. Trypacidin was the most toxic, decreasing cell viability and triggering cell lysis, both effects occurring at an IC50 close to 7 ”M. Trypacidin toxicity was also observed in the same concentration range on human bronchial epithelial cells. In the first hour of exposure, trypacidin initiates the intracellular formation of nitric oxide (NO) and hydrogen peroxide (H2O2). This oxidative stress triggers necrotic cell death in the following 24 h. The apoptosis pathway, moreover, was not involved in the cell death process as trypacidin did not induce apoptotic bodies or a decrease in mitochondrial membrane potential. This is the first time that the toxicity of trypacidin to lung cells has been reported
    • 

    corecore