The Pain–to–Well-Being Relationship in Patients Experiencing Chronic Orofacial Pain

ntroduction: Orofacial pain features may negatively influence a person's well-being and vice versa. Some aspects of well-being can be measured with axis II instruments that assess patients' psychosocial and behavioral status. The aim of this study was to investigate associations between pain features and psychosocial variables as indicators of well-being. Materials and Methods: Seven hundred ninety-nine anonymized datasets collected using the Web-based Interdisciplinary Symptom Evaluation (WISE) of patients reporting to the Interdisciplinary Orofacial Pain Unit, University of Zurich, between March 19, 2017 and May 19, 2019, were analyzed. Pain features including intensity, number of locations, impact, and duration were evaluated. Psychometric measures assessed pain-related catastrophizing and disability, illness perception, distress, anxiety, depression, injustice experience, dysmorphic concerns, and insomnia. Results: Most patients were between 30 and 59 years old (58.3%), female (69.8%), working (66.0%), and experienced pain for more than 6 months (68.5%). Pain intensities were higher in women than men and higher in disabled than working patients. Scores indicating elevated stress and depression were also observed in disabled patients. The sample prevalence rates of clinically relevant axis II instrument scores were as follows: Graded Chronic Pain Scale for the Head (GCPS-H), 27%; Patient Health Questionnaire 4 (PHQ4), 21%; PHQ9, 21%; Pain Catastrophizing Scale (PCS), 20%; General Anxiety Disorder 7 (GAD7), 15%; Insomnia Severity Index (ISI), 15%; Injustice Experience Questionnaire (IEQ), 14%; GCPS for the Body (GCPS-B), 13%; PHQ for Stress (PHQstr), 6%; and Dysmorphic Concern Questionnaire (DCQ), 2%. Noteworthy results of correlation analysis of the clinically relevant axis II scores and pain measures were as follows: the PHQstr had moderate associations (0.34-0.43) with the sum of pain intensity at rest and during function, number of pain locations, and typical pain intensity. The IEQ scores were moderately associated with typical pain intensity at 0.39. The DCQ scores were moderately associated with pain extension at 0.41. Conclusions: Moderate correlations of certain pain and well-being measures were found in patients reporting clinically relevant stress, injustice experience, and dysmorphic concern, all of which reflect impaired well-being. PHQ4 is suitable for routine distress screening in the clinical setting

Effects of Proteoliposome Composition and Draw Solution Types on Separation Performance of Aquaporin-Based Proteoliposomes:Implications for Seawater Desalination Using Aquaporin-Based Biomimetic Membranes

Aquaporins are a large family of water transport proteins in cell membranes. Their high water permeability and solute rejection make them potential building blocks for high-performance biomimetic membranes for desalination. In the current study, proteoliposomes were prepared using AquaporinZ from Escherichia coli cells, and their separation properties were characterized by stopped-flow measurements. The current study systematically investigated the effect of proteoliposome composition (lipid type, protein-to-lipid ratio (PLR), and the addition of cholesterol) on water permeability and NaCl retention. Among the various lipids investigated, 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)-based proteoliposomes were found to have excellent osmotic water permeability and NaCl reflection coefficient values. Increasing the PLR of DOPC proteoliposomes up to 1:200 increased their osmotic water permeability. However, further increase in the PLR reduced the osmotic water permeability probably due to the occurrence of defects in the proteoliposomes, whereas the addition of cholesterol improved their osmotic water permeation likely due to defects sealing. The current study also investigated the effect of major dissolved ions in seawater (e.g., Mg 2+ and SO4 2-) on the stability of proteoliposomes, and design criteria for aquaporin-based biomimetic membranes are proposed in the context of desalination. © 2013 American Chemical Society.link_to_subscribed_fulltex

Preparation of Tethered-Lipid Bilayers on Gold Surfaces for the Incorporation of Integral Membrane Proteins Synthesized by Cell-Free Expression

International audienceThere is an increasing interest to express and study membrane proteins in vitro. New techniques to produce and insert functional membrane proteins into planar lipid bilayers have to be developed. In this work, we produce a tethered lipid bilayer membrane (tBLM) to provide sufficient space for the incorporation of the integral membrane protein (IMP) Aquaporin Z (AqpZ) between the tBLM and the surface of the sensor. We use a gold (Au)-coated sensor surface compatible with mechanical sensing using a quartz crystal microbalance with dissipation monitoring (QCM-D) or optical sensing using the surface plasmon resonance (SPR) method. tBLM is produced by vesicle fusion onto a thin gold film, using phospholipid-polyethylene glycol (PEG) as a spacer. Lipid vesicles are composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-poly(ethyleneglycol)-2000-N-[3-(2-pyridyldithio)propionate], so-called DSPE-PEG-PDP, at different molar ratios (respectively, 99.5/0.5, 97.5/2.5, and 95/5 mol %), and tBLM formation is characterized using QCM-D, SPR, and atomic force technology (AFM). We demonstrate that tBLM can be produced on the gold surface after rupture of the vesicles using an α helical (AH) peptide, derived from hepatitis C virus NS5A protein, to assist the fusion process. A cell-free expression system producing the E. coli integral membrane protein Aquaporin Z (AqpZ) is directly incubated onto the tBLMs for expression and insertion of the IMP at the upper side of tBLMs. The incorporation of AqpZ into bilayers is monitored by QCM-D and compared to a control experiment (without plasmid in the cell-free expression system). We demonstrate that an IMP such as AqpZ, produced by a cell-free expression system without any protein purification, can be incorporated into an engineered tBLM preassembled at the surface of a gold-coated sensor