Objectives: CD4+ memory T cells facilitate long-termed adaptive immune responses while NK cells are predominately rapid effector cells with significant functions for both intestinal homeostasis and inflammation. We wanted to study both populations in health and pediatric inflammatory bowel disease (IBD) and correlate them with disease activity and medication.
Methods: We performed flow cytometric analyses of peripheral blood CD4 + CD45RO+ memory T cells and CD3-CD16 + CD56+ NK cells in 30 patients with IBD and 31 age-matched controls and correlated percentages of subsets with disease activity (PUCAI/PCDAI) and medication.
Objective: Endoscopic balloon dilatation (EBD) is a standard treatment for intestinal strictures in Crohn's disease (CD). No evidence-based guidelines exist regarding the balloon diameter or the balloon pressure to be used, with recent studies suggesting the use of a smaller diameter than classically used. We sought to analyze the factors associated with safety and efficacy of EBD in CD strictures, particularly looking at balloon diameter and dilatation pressure.
View Article and Find Full Text PDFWe report an easy, efficient and reproducible way to prepare Rapid-Freeze-Quench samples in sub-millimeter capillaries and load these into the probe head of a 275 GHz Electron Paramagnetic Resonance spectrometer. Kinetic data obtained for the binding reaction of azide to myoglobin demonstrate the feasibility of the method for high-frequency EPR. Experiments on the same samples at 9.
View Article and Find Full Text PDFWe report on a novel approach to the study of rates and short-lived intermediates of (bio)chemical reactions that involve paramagnetic species. Temperature-cycle Electron Paramagnetic Resonance (EPR) concerns the repeated heating of a reaction mixture in the cavity of an EPR spectrometer by pulsed irradiation with a near-infrared diode laser combined with intermittent characterization of the sample by 275 GHz EPR at a lower temperature at which the reaction does not proceed. The new technique is demonstrated for the reduction of TEMPOL with sodium dithionite in aqueous solution down to the sub-second time scale.
View Article and Find Full Text PDFCorrection for 'Conformation of bis-nitroxide polarizing agents by multi-frequency EPR spectroscopy' by Janne Soetbeer et al., Phys. Chem.
View Article and Find Full Text PDFRev Med Liege
January 2020
Proton pump inhibitors (PPI) are drugs frequently used for gastric acid-induced conditions. Their use is constantly increasing and due to the apparent absence of side-effects, the treatment is not reassessed, even for the elderly. However, there are many cases of misprescribing while concerns about some side-effects are rising.
View Article and Find Full Text PDFMulti-frequency EPR spectroscopy can provide high-level structural information on high-spin Fe sites in proteins and enzymes. Unfortunately, analysis of the EPR spectra of these spin systems is hindered by the presence of broad distributions in the zero-field-splitting (ZFS) parameters, which reflect conformational heterogeneity of the iron sites. We present the analysis of EPR spectra of high-spin Fe bound to human serum transferrin.
View Article and Find Full Text PDFAlcohol consumption is the main cause of development of chronic pancreatitis and the second etiology of acute pancreatitis. The mortality of acute pancreatitis depends on its necrotic haemorrhagic character and the initial inflammatory response, while pain, malnutrition and diabetes are the main issues in the management of chronic pancreatitis. As medical and endoscopic techniques progress, surgical indications have become increasingly rare but remain indispensable for some patients.
View Article and Find Full Text PDFBackground: Propofol use during sedation for colonoscopy can result in cardiopulmonary complications. Intravenous lidocaine can alleviate visceral pain and decrease propofol requirements during surgery. We tested the hypothesis that i.
View Article and Find Full Text PDFAcrophobia is characterized by intense fear in height situations. Virtual reality (VR) can be used to trigger such phobic fear, and VR exposure therapy (VRET) has proven effective for treatment of phobias, although it remains important to further elucidate factors that modulate and mediate the fear responses triggered in VR. The present study assessed verbal and behavioral fear responses triggered by a height simulation in a 5-sided cave automatic virtual environment (CAVE) with visual and acoustic simulation and further investigated how fear responses are modulated by immersion, i.
View Article and Find Full Text PDFThe chemical structure of polarizing agents critically determines the efficiency of dynamic nuclear polarization (DNP). For cross-effect DNP, biradicals are the polarizing agents of choice and the interaction and relative orientation of the two unpaired electrons should be optimal. Both parameters are affected by the molecular structure of the biradical in the frozen glassy matrix that is typically used for DNP/MAS NMR and likely differs from the structure observed with X-ray crystallography.
View Article and Find Full Text PDFThe incidence of pancreatic cancer is increasing, but proportion of resectable cases and survival do not increase. Then, our care strategies have to be optimized. Chemotherapy is the principal treatment of locally advanced pancreatic cancer.
View Article and Find Full Text PDFThe article has been withdrawn at the request of the authors and editor because of incorrect authorship, which is considered a form of unethical publication. The Publisher apologizes for any inconvenience this may cause.
View Article and Find Full Text PDFBackground And Study Aims: The current standard of care for resectable pancreatic ductal adenocarcinoma (PDAC) is surgery-first followed by adjuvant chemotherapy. We review our single center experience in a PDAC cohort managed by the surgery-first strategy. We then compare our data to those of Belgian and international literature.
View Article and Find Full Text PDFX-ray diffraction (XRD) and electron paramagnetic resonance spectroscopy (EPR) were combined to study the structural transformations induced by temperature, pressure and air humidity of the "breathing" metal-organic framework (MOF) MIL-53(Al), doped with paramagnetic V ions, after activation. The correlation between in situ XRD and thermogravimetric analysis measurements showed that upon heating this MOF in air, starting from ambient temperature and pressure, the narrow pore framework first dehydrates and after that makes the transition to a large pore state (lp). The EPR spectra of V[double bond, length as m-dash]O molecular ions, replacing Al-OH in the structure, also allow to distinguish the as synthesized, hydrated (np-h) and dehydrated narrow pore (np-d), and lp states of MIL-53(Al).
View Article and Find Full Text PDFInflammatory bowel diseases are chronic diseases whose long-term evolution depends on the depth of remission. Their clinical and endoscopic evaluation is imperfect. The development of confocal endomicroscopy allows microscopic images to be obtained in vivo.
View Article and Find Full Text PDFAtrial-esophageal fistula (AOF) after ablation in atrial fibrillation has a fatal outcome. Fully documented in 2004, AOF has never completely disappeared despite technological evolvements. Survival depends on early recognition and treatment.
View Article and Find Full Text PDFBackground/objectives: The epidemiology, natural history, complications, and therapeutic management of chronic pancreatitis (CP) are not well described at the national level. This multi-centre prospective observational study involving eight Belgian hospitals aimed to improve the understanding of these aspects of CP in Belgium.
Methods: All patients with a diagnosis of CP based on imaging were eligible for this study.
To understand the dynamic nuclear polarization (DNP) enhancements of biradical polarizing agents, the magnetic resonance parameters need to be known. We describe a tailored EPR approach to accurately determine electron spin-spin coupling parameters using a combination of standard (9 GHz), high (95 GHz) and ultra-high (275 GHz) frequency EPR. Comparing liquid- and frozen-solution continuous-wave EPR spectra provides accurate anisotropic dipolar interaction D and isotropic exchange interaction J parameters of the DNP biradical AMUPol.
View Article and Find Full Text PDFAppl Magn Reson
April 2016
Rapid freeze-quench (RFQ) in combination with electron paramagnetic resonance (EPR) spectroscopy at X-band is a proven technique to trap and characterize paramagnetic intermediates of biochemical reactions. Preparation of suitable samples is still cumbersome, despite many attempts to remedy this problem, and limits the wide applicability of RFQ EPR. We present a method, which improves the collection of freeze-quench particles from isopentane and their packing in an EPR tube.
View Article and Find Full Text PDFBasic steps of acute pancreatitis initial management are diagnostic assessment, severity prediction, search for concomitant abnormalities being part of the etiologic work up or requiring an early treatment. Adequate volume perfusion is certainly the most important therapeutic measure.
View Article and Find Full Text PDFSurgical resection followed by chemotherapy is the actual standard of care for localized, deemed resectable, pancreatic ductal adenocarcinoma. Despite a better selection of surgical candidates and the actual performance of expert teams, the proportion of patients with a prolonged survival has not been ameliorated during the last three decades. The morphological determinants of resectability are the subject of limitations.
View Article and Find Full Text PDFWe develop a theoretical description of Dynamic Nuclear Polarization (DNP) in solids under Magic Angle Spinning (MAS) to describe the magnetic field dependence of the DNP effect. The treatment is based on an efficient scheme for numerical solution of the Liouville-von Neumann equation, which explicitly takes into account the variation of magnetic interactions during the sample spinning. The dependence of the cross-effect MAS-DNP on various parameters, such as the hyperfine interaction, electron-electron dipolar interaction, microwave field strength, and electron spin relaxation rates, is analyzed.
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