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Interaction between cell surface integrin receptors and extracellular matrix (ECM) components plays an important role in cell survival, proliferation, and migration, including tumor development and invasion of tumor cells. Matrix metalloproteinases (MMPs) are a family of metalloproteinases capable of digesting ECM components and are important molecules for cell migration. Binding of ECM to integrins initiates cascades of cell signaling events modulating expression and activity of different MMPs. The aim of this study is to investigate fibronectin–integrin-mediated signaling and modulation of MMPs. Our findings indicated that culture of human cervical cancer cell (SiHa) on fibronectin-coated surface perhaps sends signals via fibronectin–integrin-mediated signaling pathways recruiting focal adhesion kinase (FAK) extracellular signal regulated kinase (ERK), phosphatidyl inositol 3 kinase (PI-3K), integrin-linked kinase (ILK), nuclear factor-kappa B (NF-κB), and modulates expression and activation of mainly pro-MMP-9, and moderately pro-MMP-2 in serum-free culture medium.  相似文献   
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Many studies have established gene expression-based prognostic signatures for lung cancer. All of these signatures were built from training data sets by learning the correlation of gene expression with the patients'' survival time. They require all new sample data to be normalized to the training data, ultimately resulting in common problems of low reproducibility and impracticality. To overcome these problems, we propose a new signature model which does not involve data training. We hypothesize that the imbalance of two opposing effects in lung cancer cells, represented by Yin and Yang genes, determines a patient’s prognosis. We selected the Yin and Yang genes by comparing expression data from normal lung and lung cancer tissue samples using both unsupervised clustering and pathways analyses. We calculated the Yin and Yang gene expression mean ratio (YMR) as patient risk scores. Thirty-one Yin and thirty-two Yang genes were identified and selected for the signature development. In normal lung tissues, the YMR is less than 1.0; in lung cancer cases, the YMR is greater than 1.0. The YMR was tested for lung cancer prognosis prediction in four independent data sets and it significantly stratified patients into high- and low-risk survival groups (p = 0.02, HR = 2.72; p = 0.01, HR = 2.70; p = 0.007, HR = 2.73; p = 0.005, HR = 2.63). It also showed prediction of the chemotherapy outcomes for stage II & III. In multivariate analysis, the YMR risk factor was more successful at predicting clinical outcomes than other commonly used clinical factors, with the exception of tumor stage. The YMR can be measured in an individual patient in the clinic independent of gene expression platform. This study provided a novel insight into the biology of lung cancer and shed light on the clinical applicability.  相似文献   
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Alzheimer’s disease (AD) is a progressive neurodegenerative disease with no cure till today. Aberrant activation of cell cycle regulatory proteins is implicated in neurodegenerative diseases including AD. We and others have shown that Cyclin dependent kinase 4 (Cdk4) is activated in AD brain and is required for neuron death. In this study, we tested the efficiency of commercially available Cdk4 specific inhibitors as well as a small library of synthetic molecule inhibitors targeting Cdk4 as neuroprotective agents in cellular models of neuron death. We found that several of these inhibitors significantly protected neuronal cells against death induced by nerve growth factor (NGF) deprivation and oligomeric beta amyloid (Aβ) that are implicated in AD. These neuroprotective agents inhibit specifically Cdk4 kinase activity, loss of mitochondrial integrity, induction of pro-apoptotic protein Bim and caspase3 activation in response to NGF deprivation. The efficacies of commercial and synthesized inhibitors are comparable. The synthesized molecules are either phenanthrene based or naphthalene based and they are synthesized by using Pschorr reaction and Buchwald coupling respectively as one of the key steps. A number of molecules of both kinds block neurodegeneration effectively. Therefore, we propose that Cdk4 inhibition would be a therapeutic choice for ameliorating neurodegeneration in AD and these synthetic Cdk4 inhibitors could lead to development of effective drugs for AD.  相似文献   
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The leaves of Ocimum gratissimum (Clocimum) exhibited strong volatile fungitoxicity against betelvine (Piper betle L.) pathogens—Alternaria alternata, Colletotrichum capsici and Sclerotium rolfsii. Fifteen compounds could be identified from the fungitoxic constituents—the essential oil. The oil at its minimum inhibitory concentrations of 50, 250 and 500 ppm against S. rolfsii, A. alternata and C. capsici, respectively, was fungistatic, although, fungicidal at higher concentrations. Eugenol was found to be the major fungitoxic principle in the oil. The oil was either equally effective or superior to synthetic commercial fungicides and was non-phytotoxic to the host plants. Thus, the oil can be used as a valuable indigenous and biodegradable agent against fungi that cause losses to the betelvine industry.  相似文献   
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Background

NVA237 is a once-daily dry-powder formulation of the long-acting muscarinic antagonist glycopyrronium bromide in development for the treatment of chronic obstructive pulmonary disease (COPD). The glycopyrronium bromide in COPD airways clinical study 1 (GLOW1) evaluated the efficacy, safety and tolerability of NVA237 in patients with moderate-to-severe COPD.

Methods

Patients with COPD with a smoking history of ≥ 10 pack-years, post-bronchodilator forced expiratory volume in 1 second (FEV1) < 80% and ≥ 30% predicted normal and FEV1/forced vital capacity < 0.70 were enrolled. Patients were randomized to double-blind treatment with NVA237 50 μg once daily or placebo for 26 weeks with inhaled/intranasal corticosteroids or H1 antagonists permitted in patients stabilized on them prior to study entry. The primary outcome measure was trough FEV1 at Week 12.

Results

A total of 822 patients were randomized to NVA237 (n = 552) or placebo (n = 270). Least squares mean (± standard error) trough FEV1 at Week 12 was significantly higher in patients receiving NVA237 (1.408 ± 0.0105 L), versus placebo (1.301 ± 0.0137 L; treatment difference 108 ± 14.8 mL, p < 0.001). Significant improvements in trough FEV1 were apparent at the end of Day 1 and sustained through Week 26. FEV1 was significantly improved in the NVA237 group versus placebo throughout the 24-hour periods on Day 1 and at Weeks 12 and 26, and at all other visits and timepoints. Transition dyspnoea index focal scores and St. George''s Respiratory Questionnaire scores were significantly improved with NVA237 versus placebo at Week 26, with treatment differences of 1.04 (p < 0.001) and-2.81 (p = 0.004), respectively. NVA237 significantly reduced the risk of first moderate/severe COPD exacerbation by 31% (p = 0.023) and use of rescue medication by 0.46 puffs per day (p = 0.005), versus placebo. NVA237 was well tolerated and had an acceptable safety profile, with a low frequency of cardiac and typical antimuscarinic adverse effects.

Conclusions

Once-daily NVA237 was safe and well tolerated and provided rapid, sustained improvements in lung function, improvements in dyspnoea, and health-related quality of life, and reduced the risk of exacerbations and the use of rescue medication.

Trial registration

ClinicalTrials.gov: NCT01005901  相似文献   
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