72 research outputs found

    Biased TAS2R Bronchodilators Inhibit Airway Smooth Muscle Growth by Downregulating Phosphorylated Extracellular Signal–regulated Kinase 1/2

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    Bitter taste receptor (TAS2R) agonists dilate airways by receptor-dependent smooth muscle relaxation. Besides their coupling to relaxation, we have found that human airway smooth muscle (HASM) cell TAS2Rs activate (phosphorylate) extracellular signal–related kinase 1/2 (ERK1/2), but the cellular effects are not known. In the present study, we show in HASM cells that TAS2R agonists initially stimulate phosphorylated ERK1/2 (pERK1/2) but by 24 hours cause a marked (50–70%) downregulation of pERK1/2 without a change in total ERK1/2. It was hypothesized that TAS2R agonists suppress cell growth through this pERK1/2 downregulation. Agonist-dependent inhibition of cell proliferation was indeed found in HASM cells derived from normal and asthmatic human lungs, as well as in an immortalized HASM cell line. pERK1/2 downregulation was linked to downregulation of the upstream kinase MEK1/2 (mitogen-activated protein kinase/extracellular signal–regulated kinase). Various structurally diverse TAS2R agonists evoked a range of inhibition of HASM proliferation, the magnitude of which directly correlated with the downregulation of pERK1/2 (R^2 = 0.86). Some TAS2R agonists were as effective as pharmacological inhibitors of Raf1 and MEK1/2 in suppressing growth. siRNA silencing of TAS2Rs (subtypes 10, 14, and 31) ablated the pERK1/2 and growth-inhibitory effects of TAS2R agonists. These phenotypes were attenuated by inhibiting the TAS2R G protein G_(αi) and by knocking down β-arrestin 1/2, indicating a dual pathway, although there may be additional mechanisms involved in this HASM TAS2R multidimensional signaling. Thus, TAS2R agonist structure can be manipulated to maintain the relaxation response and can be biased toward suppression of HASM growth. The latter response is of potential therapeutic benefit in asthma, in which an increase in smooth muscle mass contributes to airway obstruction

    Drug-Induced Regulation of Target Expression

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    Drug perturbations of human cells lead to complex responses upon target binding. One of the known mechanisms is a (positive or negative) feedback loop that adjusts the expression level of the respective target protein. To quantify this mechanism systems-wide in an unbiased way, drug-induced differential expression of drug target mRNA was examined in three cell lines using the Connectivity Map. To overcome various biases in this valuable resource, we have developed a computational normalization and scoring procedure that is applicable to gene expression recording upon heterogeneous drug treatments. In 1290 drug-target relations, corresponding to 466 drugs acting on 167 drug targets studied, 8% of the targets are subject to regulation at the mRNA level. We confirmed systematically that in particular G-protein coupled receptors, when serving as known targets, are regulated upon drug treatment. We further newly identified drug-induced differential regulation of Lanosterol 14-alpha demethylase, Endoplasmin, DNA topoisomerase 2-alpha and Calmodulin 1. The feedback regulation in these and other targets is likely to be relevant for the success or failure of the molecular intervention

    Spillway-Induced Salmon Head Injury Triggers the Generation of Brain αII-Spectrin Breakdown Product Biomarkers Similar to Mammalian Traumatic Brain Injury

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    Recent advances in biomedical research have resulted in the development of specific biomarkers for diagnostic testing of disease condition or physiological risk. Of specific interest are αII-spectrin breakdown products (SBDPs), which are produced by proteolytic events in traumatic brain injury and have been used as biomarkers to predict the severity of injury in humans and other mammalian brain injury models. This study describes and demonstrates the successful use of antibody-based mammalian SBDP biomarkers to detect head injury in migrating juvenile Chinook salmon (Oncorhynchus tshawytscha) that have been injured during passage through high-energy hydraulic environments present in spillways under different operational configurations. Mortality and injury assessment techniques currently measure only near-term direct mortality and easily observable acute injury. Injury-based biomarkers may serve as a quantitative indicator of subacute physical injury and recovery, and aid hydropower operators in evaluation of safest passage configuration and operation actions for migrating juvenile salmonids. We describe a novel application of SBDP biomarkers for head injury for migrating salmon. To our knowledge, this is the first documented cross-over use of a human molecular biomarker in a wildlife and operational risk management scenario

    Activation of NF-kB Pathway by Virus Infection Requires Rb Expression

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    The retinoblastoma protein Rb is a tumor suppressor involved in cell cycle control, differentiation, and inhibition of oncogenic transformation. Besides these roles, additional functions in the control of immune response have been suggested. In the present study we investigated the consequences of loss of Rb in viral infection. Here we show that virus replication is increased by the absence of Rb, and that Rb is required for the activation of the NF-kB pathway in response to virus infection. These results reveal a novel role for tumor suppressor Rb in viral infection surveillance and further extend the concept of a link between tumor suppressors and antiviral activity

    Modifying Ligand-Induced and Constitutive Signaling of the Human 5-HT4 Receptor

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    G protein–coupled receptors (GPCRs) signal through a limited number of G-protein pathways and play crucial roles in many biological processes. Studies of their in vivo functions have been hampered by the molecular and functional diversity of GPCRs and the paucity of ligands with specific signaling effects. To better compare the effects of activating different G-protein signaling pathways through ligand-induced or constitutive signaling, we developed a new series of RASSLs (receptors activated solely by synthetic ligands) that activate different G-protein signaling pathways. These RASSLs are based on the human 5-HT4b receptor, a GPCR with high constitutive Gs signaling and strong ligand-induced G-protein activation of the Gs and Gs/q pathways. The first receptor in this series, 5-HT4-D100A or Rs1 (RASSL serotonin 1), is not activated by its endogenous agonist, serotonin, but is selectively activated by the small synthetic molecules GR113808, GR125487, and RO110-0235. All agonists potently induced Gs signaling, but only a few (e.g., zacopride) also induced signaling via the Gq pathway. Zacopride-induced Gq signaling was enhanced by replacing the C-terminus of Rs1 with the C-terminus of the human 5-HT2C receptor. Additional point mutations (D66A and D66N) blocked constitutive Gs signaling and lowered ligand-induced Gq signaling. Replacing the third intracellular loop of Rs1 with that of human 5-HT1A conferred ligand-mediated Gi signaling. This Gi-coupled RASSL, Rs1.3, exhibited no measurable signaling to the Gs or Gq pathway. These findings show that the signaling repertoire of Rs1 can be expanded and controlled by receptor engineering and drug selection

    Steroids in kidney transplant patients

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    Any evaluation of steroids in kidney transplantation is hampered by individual variability in metabolism, the lack of clinically available steroid blood levels, and overall little attention to steroid exposure. Many feel that steroids were an essential part of chronic immunosuppression in past decades but may no longer be necessary in low-risk populations when our newer and more potent drugs are used. Potential differences in long-term outcome will be unapparent in short-term antibody induction studies in low-risk patients, particularly with low on steroid doses, as may have happened in the recent, well-done Astellas trial. In many studies, the evidence for the superiority of mycophenolate (MMF) and tacrolimus (TAC) was not as strong as the evidence for the benefit of steroids in the Canadian cyclosporine study. As the practice of steroid withdrawal has increased, we have not seen the improvement in long-term graft survival that many expected with our newer agents. Steroids have immunosuppressive effects even in doses that are low by historic standards, and side effects may not justify their abandonment

    Increased Mitochondrial Calcium Sensitivity and Abnormal Expression of Innate Immunity Genes Precede Dopaminergic Defects in Pink1-Deficient Mice

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    BACKGROUND: PTEN-induced kinase 1 (PINK1) is linked to recessive Parkinsonism (EOPD). Pink1 deletion results in impaired dopamine (DA) release and decreased mitochondrial respiration in the striatum of mice. To reveal additional mechanisms of Pink1-related dopaminergic dysfunction, we studied Ca²+ vulnerability of purified brain mitochondria, DA levels and metabolism and whether signaling pathways implicated in Parkinson\u27s disease (PD) display altered activity in the nigrostriatal system of Pink1⁻/⁻ mice. METHODS AND FINDINGS: Purified brain mitochondria of Pink1⁻/⁻ mice showed impaired Ca²+ storage capacity, resulting in increased Ca²+ induced mitochondrial permeability transition (mPT) that was rescued by cyclosporine A. A subpopulation of neurons in the substantia nigra of Pink1⁻/⁻ mice accumulated phospho-c-Jun, showing that Jun N-terminal kinase (JNK) activity is increased. Pink1⁻/⁻ mice 6 months and older displayed reduced DA levels associated with increased DA turnover. Moreover, Pink1⁻/⁻ mice had increased levels of IL-1β, IL-12 and IL-10 in the striatum after peripheral challenge with lipopolysaccharide (LPS), and Pink1⁻/⁻ embryonic fibroblasts showed decreased basal and inflammatory cytokine-induced nuclear factor kappa-β (NF-κB) activity. Quantitative transcriptional profiling in the striatum revealed that Pink1⁻/⁻ mice differentially express genes that (i) are upregulated in animals with experimentally induced dopaminergic lesions, (ii) regulate innate immune responses and/or apoptosis and (iii) promote axonal regeneration and sprouting. CONCLUSIONS: Increased mitochondrial Ca²+ sensitivity and JNK activity are early defects in Pink1⁻/⁻ mice that precede reduced DA levels and abnormal DA homeostasis and may contribute to neuronal dysfunction in familial PD. Differential gene expression in the nigrostriatal system of Pink1⁻/⁻ mice supports early dopaminergic dysfunction and shows that Pink1 deletion causes aberrant expression of genes that regulate innate immune responses. While some differentially expressed genes may mitigate neurodegeneration, increased LPS-induced brain cytokine expression and impaired cytokine-induced NF-κB activation may predispose neurons of Pink1⁻/⁻ mice to inflammation and injury-induced cell death

    Human malarial disease: a consequence of inflammatory cytokine release

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    Malaria causes an acute systemic human disease that bears many similarities, both clinically and mechanistically, to those caused by bacteria, rickettsia, and viruses. Over the past few decades, a literature has emerged that argues for most of the pathology seen in all of these infectious diseases being explained by activation of the inflammatory system, with the balance between the pro and anti-inflammatory cytokines being tipped towards the onset of systemic inflammation. Although not often expressed in energy terms, there is, when reduced to biochemical essentials, wide agreement that infection with falciparum malaria is often fatal because mitochondria are unable to generate enough ATP to maintain normal cellular function. Most, however, would contend that this largely occurs because sequestered parasitized red cells prevent sufficient oxygen getting to where it is needed. This review considers the evidence that an equally or more important way ATP deficency arises in malaria, as well as these other infectious diseases, is an inability of mitochondria, through the effects of inflammatory cytokines on their function, to utilise available oxygen. This activity of these cytokines, plus their capacity to control the pathways through which oxygen supply to mitochondria are restricted (particularly through directing sequestration and driving anaemia), combine to make falciparum malaria primarily an inflammatory cytokine-driven disease

    Feasibility of preoperative chemotherapy for locally advanced, operable colon cancer: The pilot phase of a randomised controlled trial

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    Summary: Background Preoperative (neoadjuvant) chemotherapy and radiotherapy are more eff ective than similar postoperative treatment for oesophageal, gastric, and rectal cancers, perhaps because of more eff ective micrometastasis eradication and reduced risk of incomplete excision and tumour cell shedding during surgery. The FOxTROT trial aims to investigate the feasibility, safety, and effi cacy of preoperative chemotherapy for colon cancer. Methods In the pilot stage of this randomised controlled trial, 150 patients with radiologically staged locally advanced (T3 with ≥5 mm invasion beyond the muscularis propria or T4) tumours from 35 UK centres were randomly assigned (2:1) to preoperative (three cycles of OxMdG [oxaliplatin 85 mg/m², l-folinic acid 175 mg, fl uorouracil 400 mg/m² bolus, then 2400 mg/m² by 46 h infusion] repeated at 2-weekly intervals followed by surgery and a further nine cycles of OxMdG) or standard postoperative chemotherapy (12 cycles of OxMdG). Patients with KRAS wild-type tumours were randomly assigned (1:1) to receive panitumumab (6 mg/kg; every 2 weeks with the fi rst 6 weeks of chemotherapy) or not. Treatment allocation was through a central randomisation service using a minimised randomisation procedure including age, radiological T and N stage, site of tumour, and presence of defunctioning colostomy as stratifi cation variables. Primary outcome measures of the pilot phase were feasibility, safety, and tolerance of preoperative therapy, and accuracy of radiological staging. Analysis was by intention to treat. This trial is registered, number ISRCTN 87163246. Findings 96% (95 of 99) of patients started and 89% (85 of 95) completed preoperative chemotherapy with grade 3–4 gastrointestinal toxicity in 7% (seven of 94) of patients. All 99 tumours in the preoperative group were resected, with no signifi cant diff erences in postoperative morbidity between the preoperative and control groups: 14% (14 of 99) versus 12% (six of 51) had complications prolonging hospital stay (p=0·81). 98% (50 of 51) of postoperative chemotherapy patients had T3 or more advanced tumours confi rmed at post-resection pathology compared with 91% (90 of 99) of patients following preoperative chemotherapy (p=0·10). Preoperative therapy resulted in signifi cant downstaging of TNM5 compared with the postoperative group (p=0·04), including two pathological complete responses, apical node involvement (1% [one of 98] vs 20% [ten of 50], p<0·0001), resection margin involvement (4% [ four of 99] vs 20% [ten of 50], p=0·002), and blinded centrally scored tumour regression grading: 31% (29 of 94) vs 2% (one of 46) moderate or greater regression (p=0·0001). Interpretation Preoperative chemotherapy for radiologically staged, locally advanced operable primary colon cancer is feasible with acceptable toxicity and perioperative morbidity. Proceeding to the phase 3 trial, to establish whether the encouraging pathological responses seen with preoperative therapy translates into improved long-term oncological outcome, is appropriate

    Food service management web platform based on XML specification and web services

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    Company’s importance and competitiveness is no longer just to enable automatic processes but also to fulfill needs of humans as we nowadays also live concerned with enjoyment and pleasure, in order to complement people's lives. Built from the decision to bring to market a fully customized product to the customer comes the Fragus Company. This company enables services of Personal Chef and Bartender aiming to bring convenience in one of life's greatest pleasures: eating. This publication aims at briefly describing a web platform of this company and its usefulness, which is to some extend provided by the use of structured data based on XML and related technologies, for better supporting the Company’s services and to enable an easy way for information storing and processing over the web, namely through web services.Aichi Science and Technology Foundation (PTDC/EME-GIN/102143/2008
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