247 research outputs found

    Uncertainty analysis of the use of a retailer fidelity card scheme in the assessment of food additive intake

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    International audienceThe feasibility of using a retailer fidelity card scheme to estimate food additive intake has been investigated in an earlier study. Fidelity card survey information was combined with information provided by the retailer on levels of the food colour Sunset Yellow (E110) in the foods to estimate a daily exposure to the additive in the Swiss population. As with any dietary exposure method the fidelity card scheme is subject to uncertainties and in this paper the impact of uncertainties associated with input variables including amounts of food purchased, levels of E110 in food, proportion of food purchased at retailer, rate of fidelity card usage, proportion of foods consumed outside of home and bodyweights and with systematic uncertainties has been assessed using a qualitative, deterministic and probabilistic approach. An analysis of the sensitivity of the results to each of the probabilistic inputs was also undertaken. The analysis was able to identify the key factors responsible for uncertainty within the model and demonstrate how the application of some simple probabilistic approaches can be used to quantitatively assess uncertainty

    Clinical Efficacy of Enzalutamide vs Bicalutamide Combined With Androgen Deprivation Therapy in Men With Metastatic Hormone-Sensitive Prostate Cancer: A Randomized Clinical Trial

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    Importance: Black patients have been underrepresented in prospective clinical trials of advanced prostate cancer. This study evaluated the efficacy of enzalutamide compared with bicalutamide, with planned subset analysis of Black patients with metastatic hormone-sensitive prostate cancer (mHSPC), which is a disease state responsive to androgen deprivation therapy (ADT). Objective: To compare the efficacy of enzalutamide vs bicalutamide in combination with ADT in men with mHSPC, with a subset analysis of Black patients. Design, Setting, and Participants: In this randomized clinical trial, a phase 2 screening design enabled a nondefinitive comparison of the primary outcome by treatment. Patients were stratified by race (Black or other) and bone pain (present or absent). Accrual of at least 30% Black patients was required. This multicenter trial was conducted at 4 centers in the US. Men with mHSPC with no history of seizures and adequate marrow, renal, and liver function were eligible. Data analysis was performed from February 2019 to March 2020. Interventions: Participants were randomized 1:1 to receive oral enzalutamide (160 mg daily) or bicalutamide (50 mg daily) in addition to ADT. Main Outcomes and Measures: The primary end point was the 7-month prostate-specific antigen (PSA) response (SMPR) rate, a previously accepted surrogate for overall survival (OS) outcome. Secondary end points included adverse reactions, time to PSA progression, and OS. Results: A total of 71 men (median [range] age, 65 [51-86] years) were enrolled; 29 (41%) were Black, 41 (58%) were White, and 1 (1%) was Asian. Thirty-six patients were randomized to receive enzalutamide, and 35 were randomized to receive bicalutamide. Twenty-six patients (37%) had bone pain and 37 patients (52%) had extensive disease. SMPR was achieved in 30 of 32 patients (94%; 95% CI, 80%-98%) taking enzalutamide and 17 of 26 patients (65%; 95% CI, 46%-81%) taking bicalutamide (P = .008) (difference, 29%; 95% CI, 5%-50%). Among Black patients, the SMPR was 93% (95% CI, 69%-99%) among those taking enzalutamide and 42% (95% CI, 19%-68%) among those taking bicalutamide (P = .009); among non-Black patients, the SMPR was 94% (95% CI, 74%-99%) among those taking enzalutamide and 86% (95% CI, 60%-96%) among those taking bicalutamide. The 12-month PSA response rates were 84% with enzalutamide and 34% with bicalutamide. Conclusions and Relevance: The findings of this randomized clinical trial comparing enzalutamide with bicalutamide suggest that enzalutamide is associated with improved outcomes compared with bicalutamide, in terms of the rate and duration of PSA response, in Black patients with mHSPC. Trial Registration: ClinicalTrials.gov Identifier: NCT02058706

    Molecular Modeling of Mechanosensory Ion Channel Structural and Functional Features

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    The DEG/ENaC (Degenerin/Epithelial Sodium Channel) protein family comprises related ion channel subunits from all metazoans, including humans. Members of this protein family play roles in several important biological processes such as transduction of mechanical stimuli, sodium re-absorption and blood pressure regulation. Several blocks of amino acid sequence are conserved in DEG/ENaC proteins, but structure/function relations in this channel class are poorly understood. Given the considerable experimental limitations associated with the crystallization of integral membrane proteins, knowledge-based modeling is often the only route towards obtaining reliable structural information. To gain insight into the structural characteristics of DEG/ENaC ion channels, we derived three-dimensional models of MEC-4 and UNC-8, based on the available crystal structures of ASIC1 (Acid Sensing Ion Channel 1). MEC-4 and UNC-8 are two DEG/ENaC family members involved in mechanosensation and proprioception respectively, in the nematode Caenorhabditis elegans. We used these models to examine the structural effects of specific mutations that alter channel function in vivo. The trimeric MEC-4 model provides insight into the mechanism by which gain-of-function mutations cause structural alterations that result in increased channel permeability, which trigger cell degeneration. Our analysis provides an introductory framework to further investigate the multimeric organization of the DEG/ENaC ion channel complex

    Residents' perceptions of a night float system

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    Background. A Night Float (NF) system has been implemented by many institutions to address increasing concerns about residents' work hours. The purpose of our study was to examine the perceptions of residents towards a NF system. Methods. A 115-item questionnaire was developed to assess residents' perceptions of the NF rotation as compared with a regular call month. The categories included patient care, education, medical errors, and overall satisfaction. Internal Medicine housestaff (post-graduate years 1-3) from three hospital settings at the University of Pittsburgh completed the questionnaire. Results. The response rate was 90% (n = 149). Of these, 74 had completed the NF rotation. The housestaff felt that the quality of patient care was improved because of NF (41% agreed and 18% disagreed). A majority also felt that better care was provided by a rested physician in spite of being less familiar with the patient (46% agreed and 21% disagreed). Most felt that there was less emphasis on education (65%) and more emphasis on service (52%) during NF. Overall, the residents felt more rested during their call months (83%) and strongly supported the 80-hour workweek requirement (77%). Conclusion. Housestaff felt that the overall quality of patient care was improved by a NF system. The perceived improved quality of care by a rested physician coupled with a perceived decrease in the emphasis on education may have significant implications in housestaff training. © 2009 Jasti et al; licensee BioMed Central Ltd

    Functional Modifications of Acid-Sensing Ion Channels by Ligand-Gated Chloride Channels

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    Together, acid-sensing ion channels (ASICs) and epithelial sodium channels (ENaC) constitute the majority of voltage-independent sodium channels in mammals. ENaC is regulated by a chloride channel, the cystic fibrosis transmembrane conductance regulator (CFTR). Here we show that ASICs were reversibly inhibited by activation of GABAA receptors in murine hippocampal neurons. This inhibition of ASICs required opening of the chloride channels but occurred with both outward and inward GABAA receptor-mediated currents. Moreover, activation of the GABAA receptors modified the pharmacological features and kinetic properties of the ASIC currents, including the time course of activation, desensitization and deactivation. Modification of ASICs by open GABAA receptors was also observed in both nucleated patches and outside-out patches excised from hippocampal neurons. Interestingly, ASICs and GABAA receptors interacted to regulate synaptic plasticity in CA1 hippocampal slices. The activation of glycine receptors, which are similar to GABAA receptors, also modified ASICs in spinal neurons. We conclude that GABAA receptors and glycine receptors modify ASICs in neurons through mechanisms that require the opening of chloride channels

    Predictors of inhospital mortality and re-hospitalization in older adults with community-acquired pneumonia: a prospective cohort study

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    <p>Abstract</p> <p>Background</p> <p>A better understanding of potentially modifiable predictors of in-hospital mortality and re-admission to the hospital following discharge may help to improve management of community-acquired pneumonia in older adults. We aimed to assess the associations of potentially modifiable factors with mortality and re-hospitalization in older adults hospitalized with community-acquired pneumonia.</p> <p>Methods</p> <p>A prospective cohort study was conducted from July 2003 to April 2005 in two Canadian cities. Patients aged 65 years or older hospitalized for community-acquired pneumonia were followed up for up to 30 days from initial hospitalization for mortality and these patients who were discharged alive within 30 days of initial hospitalization were followed up to 90 days of initial hospitalization for re-hospitalization. Separate logistic regression analyses were performed identify the predictors of mortality and re-hospitalization.</p> <p>Results</p> <p>Of 717 enrolled patients hospitalized for community-acquired pneumonia, 49 (6.8%) died within 30 days of hospital admission. Among these patients, 526 were discharged alive within 30 days of hospitalization of whom 58 (11.2%) were re-hospitalized within 90 days of initial hospitalization. History of hip fracture (odds ratio (OR) = 4.00, 95% confidence interval (CI) = (1.46, 10.96), P = .007), chronic obstructive pulmonary disease (OR = 2.31, 95% CI = (1.18, 4.50), P = .014), cerebrovascular disease (OR = 2.11, 95% CI = (1.03, 4.31), P = .040) were associated with mortality. Male sex (OR = 2.35, 95% CI = (1.13, 4.85), P = .022) was associated with re-hospitalization while vitamin E supplementation was protective (OR = 0.37 (0.16, 0.90), P = .028). Lower socioeconomic status, prior influenza and pneumococcal vaccinations, appropriate antibiotic prescription upon admission, and lower nutrition risk were not significantly associated with mortality or re-hospitalization.</p> <p>Conclusion</p> <p>Chronic comorbidities appear to be the most important predictors of death and re-hospitalization in older adults hospitalized with community-acquired pneumonia while vitamin E supplementation was protective.</p

    Suppression of uPA and uPAR Attenuates Angiogenin Mediated Angiogenesis in Endothelial and Glioblastoma Cell Lines

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    In our earlier reports, we showed that downregulation of uPA and uPAR inhibited glioma tumor angiogenesis in SNB19 cells, and intraperitoneal injection of a hairpin shRNA expressing plasmid targeting uPA and uPAR inhibited angiogenesis in nude mice. The exact mechanism by which inhibition of angiogenesis takes place is not clearly understood.In the present study, we have attempted to investigate the mechanism by which uPA/uPAR downregulation by shRNA inhibits angiogenesis in endothelial and glioblastoma cell lines. uPA/uPAR downregulation by shRNA in U87 MG and U87 SPARC co-cultures with endothelial cells inhibited angiogenesis as assessed by in vitro angiogenesis assay and in vivo dorsal skin-fold chamber model in nude mice. Protein antibody array analysis of co-cultures of U87 and U87 SPARC cells with endothelial cells treated with pU2 (shRNA against uPA and uPAR) showed decreased angiogenin secretion and angiopoietin-1 as well as several other pro-angiogenic molecules. Therefore, we investigated the role of angiogenin and found that nuclear translocation, ribonucleolytic and 45S rRNA synthesis, which are all critical for angiogenic function of angiogenin, were significantly inhibited in endothelial cells transfected with uPA, uPAR and uPA/uPAR when compared with controls. Moreover, uPA and uPAR downregulation significantly inhibited the phosphorylation of Tie-2 receptor and also down regulated FKHR activation in the nucleus of endothelial cells via the GRB2/AKT/BAD pathway. Treatment of endothelial cells with ruPA increased angiogenin secretion and angiogenin expression as determined by ELISA and western blotting in a dose-dependent manner. The amino terminal fragment of uPA down regulated ruPA-induced angiogenin in endothelial cells, thereby suggesting that uPA plays a critical role in positively regulating angiogenin in glioblastoma cells.Taken together, our results suggest that uPA/uPAR downregulation suppresses angiogenesis in endothelial cells induced by glioblastoma cell lines partially by downregulation of angiogenin and by inhibition of the angiopoietin-1/AKT/FKHR pathway

    Pore-opening mechanism in trimeric P2X receptor channels

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    The opening of ion channels in response to ligand binding, voltage or membrane stretch underlies electrical and chemical signalling throughout biology. Two structural classes of pore-opening mechanisms have been established, including bending of pore-lining helices in the case of tetrameric cation channels, or tilting of such helices in mechanosensitive channels. In this paper, we explore how the structure of the pore changes during opening in P2X receptors by measuring the modification of introduced cysteine residues in transmembrane helices by thiol-reactive reagents, and by engineering metal bridges. Our results are consistent with the X-ray structure of the closed state, and demonstrate that expansion of the gate region in the external pore is accompanied by a significant narrowing of the inner pore, indicating that pore-forming helices straighten on ATP binding to open the channel. This unique pore-opening mechanism has fundamental implications for the role of subunit interfaces in the gating mechanism of P2X receptors and points to a role of the internal pore in ion permeation

    Green Synthesis of Zinc Oxide Nanoparticles from Althaea officinalis Flower Extract Coated with Chitosan for Potential Healing Effects on Diabetic Wounds by Inhibiting TNF-&alpha; and IL-6/IL-1&beta; Signaling Pathways

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    Sammar Fathy Elhabal,1 Nashwa Abdelaal,2 Saeed Abdul Kareem Saeed Al-Zuhairy,3 Mohamed Fathi Mohamed Elrefai,4,5 Ahmed Mohsen Elsaid Hamdan,6 Mohamed Mansour Khalifa,7 Sandra Hababeh,8 Mohammad Ahmad Khasawneh,9 Gehad M Khamis,10 Jakline Nelson,11 Passant M Mohie,10 Rania A Gad,12 Amira Rizk,13 Soad L Kabil,14 Mohamed Kandeel El-Ashery,15,16 Bhaskara R Jasti,17 Nahla A Elzohairy,18,19 Tayseer Elnawawy,20 Fatma E Hassan,21,22 Mohamed A El- Nabarawi23 1Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Modern University for Technology and Information (MTI), Mokattam, Cairo, Egypt; 2Department of Integrative Physiology, Baylor College of Medicine, Houston, TX, USA; 3Department of Pharmacy, Kut University College, Kut, Wasit, Iraq; 4Department of Anatomy, Histology, Physiology and Biochemistry, Faculty of Medicine, The Hashemite University, Zarqa, Jordan; 5Department of Anatomy and Embryology, Faculty of Medicine, Ain Shams University, Cairo, Egypt; 6Department of Pharmacy Practice, Faculty of Pharmacy, University of Tabuk, Tabuk, Saudi Arabia; 7Department of Human Physiology, Faculty of Medicine, Cairo University, Cairo, Egypt; 8Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; 9Department of Chemistry, College of Science U.A.E. University, Al-Ain, United Arab Emirates; 10Department of Clinical Pharmacology, Faculty of Medicine, Alexandria University, Alexandria, Egypt; 11Department of Microbiology and Immunology, Faculty of Pharmacy, Nahda University, Beni-Suef, Egypt; 12Department of Pharmacology and Toxicology, Faculty of Pharmacy, Nahda University, Beni-Suef, Egypt; 13Food Science and Technology Department, Faculty of Agricultural, Tanta University, Tanta, Egypt; 14Department of Clinical Pharmacology, Faculty of Medicine, Zagazig University, Zagazig, Egypt; 15Pharmaceutical Chemistry Department, Faculty of Pharmacy, Cairo University, Cairo, Egypt; 16Medicinal Chemistry Department, Faculty of Pharmacy, King Salman International University, Ras-Sedr, South Sinai, Egypt; 17Department of Pharmaceutics and Medicinal Chemistry, Thomas J. Long School of Pharmacy, University of the Pacific, Stockton, CA, USA; 18Air Force Specialized Hospital, Cairo, Egypt; 19Department of Microbiology and Immunology, Faculty of Pharmacy, Modern University for Technology and Information (MTI), Mokattam, Cairo, Egypt; 20Department of Pharmaceutics, Egyptian Drug Authority, Cairo, Egypt; 21Medical Physiology Department, Faculty of Medicine, Cairo University, Giza, Egypt; 22General Medicine Practice Program, Department of Physiology, Batterjee Medical College, Jeddah, Saudi Arabia; 23Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Cairo, EgyptCorrespondence: Sammar Fathy Elhabal, Email [email protected]; [email protected]; Mohamed A El- Nabarawi, Email [email protected]: Diabetes Mellitus is a multisystem chronic pandemic, wound inflammation, and healing are still major issues for diabetic patients who may suffer from ulcers, gangrene, and other wounds from uncontrolled chronic hyperglycemia. Marshmallows or Althaea officinalis (A.O.) contain bioactive compounds such as flavonoids and phenolics that support wound healing via antioxidant, anti-inflammatory, and antibacterial properties. Our study aimed to develop a combination of eco-friendly formulations of green synthesis of ZnO-NPs by Althaea officinalis extract and further incorporate them into 2% chitosan (CS) gel.Method and Results: First, develop eco-friendly green Zinc Oxide Nanoparticles (ZnO-NPs) and incorporate them into a 2% chitosan (CS) gel. In-vitro study performed by UV-visible spectrum analysis showed a sharp peak at 390 nm, and Energy-dispersive X-ray (EDX) spectrometry showed a peak of zinc and oxygen. Besides, Fourier transforms infrared (FTIR) was used to qualitatively validate biosynthesized ZnO-NPs, and transmission electron microscope (TEM) showed spherical nanoparticles with mean sizes of 76 nm and Zeta potential +30mV. The antibacterial potential of A.O.-ZnO-NPs-Cs was examined by the diffusion agar method against Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Based on the zone of inhibition and minimal inhibitory indices (MIC). In addition, an in-silico study investigated the binding affinity of A.O. major components to the expected biological targets that may aid wound healing. Althaea Officinalis, A.O-ZnO-NPs group showed reduced downregulation of IL-6, IL-1β, and TNF-α and increased IL-10 levels compared to the control group signaling pathway expression levels confirming the improved anti-inflammatory effect of the self-assembly method. In-vivo study and histopathological analysis revealed the superiority of the nanoparticles in reducing signs of inflammation and wound incision in rat models.Conclusion: These biocompatible green zinc oxide nanoparticles, by using Althaea Officinalis chitosan gel ensure an excellent new therapeutic approach for quickening diabetic wound healing. Keywords: wound healing, antimicrobial, antioxidant, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, chitosan, wound concentration, wound incisio
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