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61.
62.
Kruidenier L Kuiper I Van Duijn W Mieremet-Ooms MA van Hogezand RA Lamers CB Verspaget HW 《The Journal of pathology》2003,201(1):17-27
Intestinal mucosal damage in the inflammatory bowel diseases (IBD) Crohn's disease (CD) and ulcerative colitis (UC) involves reactive oxygen metabolites (ROMs). ROMs are neutralized by endogenous antioxidant enzymes in a carefully balanced two-step pathway. Superoxide dismutases (SODs) convert superoxide anion to hydrogen peroxide (H(2)O(2)), which is subsequently neutralized to water by catalase (CAT) or glutathione peroxidase (GPO). Remarkably changed expression levels of the three isoforms of SOD in paired non-inflamed and inflamed mucosae from CD and UC patients have been previously reported in comparison to normal control mucosa. Most notable was the strong up-regulation of Mn-SOD in inflamed epithelium. It was hypothesized that in order to provide optimal protection against ROM-mediated damage, these changes should be coordinately counterbalanced by an increased H(2)O(2)-neutralizing capacity. Therefore, the same tissue samples were used to assess the levels, activities, and/or localization of the most prominent mucosal H(2)O(2)-related antioxidants CAT, GPO, glutathione (GSH), myeloperoxidase (MPO), and metallothionein (MT). Quantitative measurements showed that in both CD and UC patients, intestinal inflammation was associated with increased activities of CAT, GPO, and MPO, whereas the mucosal GSH content was unaffected and the concentration of MT was decreased. Despite this overall increase in mucosal H(2)O(2)-metabolizing enzyme capacity, immunohistochemical analysis revealed a differentially disturbed antioxidant balance in IBD epithelium and lamina propria. In the lamina propria, the risk of direct H(2)O(2)-mediated damage seemed to be restrained by the increasing numbers of CAT- and MPO-positive monocytes/macrophages and neutrophils that infiltrated the inflamed areas. On the other hand, MPO overexpression might increase the lamina propria levels of hypochlorous acid, a stable ROM with multiple pro-inflammatory effects. In the epithelium, the number of cells that expressed CAT remained unchanged during inflammation and GPO was found in only a very low and constant number of epithelial cells. In addition, the inflamed epithelium displayed decreased expression of the hydroxyl radical (OH(*)) scavenger MT. In view of the high epithelial SOD levels in inflamed IBD epithelium, it is speculated that the efficient removal of excess H(2)O(2) is hampered in these cells, thereby increasing not only the risk of detrimental effects of H(2)O(2) directly, but also those of its extremely reactive derivatives such as OH(*). Taken together, the results suggest an imbalanced and inefficient endogenous antioxidant response in the intestinal mucosa of IBD patients, which may contribute to both the pathogenesis and the perpetuation of the inflammatory processes. 相似文献
63.
Ojeleke Olabayo Groot Wim Pavlova Milena 《Zeitschrift fur Gesundheitswissenschaften》2022,30(3):747-762
Journal of Public Health - This study reviews the empirical evidence on care delivery in complex emergencies (CEs) to better understand ways of improving care delivery and mitigating inequity in... 相似文献
64.
Schuerwegen Alana Huys Wim Coppens Violette De Neef Nele Henckens Josée Goethals Kris Morrens Manuel 《Archives of sexual behavior》2021,50(3):1197-1206
Archives of Sexual Behavior - Despite the gaining popularity in mainstream media of the phenomenon that is BDSM, empirical research on the motives and underlying psychological mechanisms driving... 相似文献
65.
Van Drongelen W Koch H Marcuccilli C Pena F Ramirez JM 《Journal of neurophysiology》2003,90(3):1571-1580
Slices (n = 45) from the somatosensory cortex of mouse (P8-13) generated spontaneous bursts of activity (0.10 +/- 0.05 Hz) that were recorded extracellularly. Multiunit action potential (AP) activity was integrated and used as an index of population activity. In this experimental model, seizure-like activity (SLA) was evoked with bicuculline (5-10 microM) or N-methyl-d-aspartate (NMDA, 5 microM). SLA was an episode with repetitive bursting at a frequency of 0.50 +/- 0.06 Hz. To evaluate whether SLA was associated with a change in synchrony, we obtained simultaneous intracellular and extracellular recordings (n = 40) and quantified the relationship between individual cells and the surrounding population of neurons. During the SLA there was an increase in population activity and bursting activity was observed in neurons and areas that were previously silent. We defined synchrony as cellular activity that is consistently locked with the population bursts. Signal-averaging techniques were used to determine this component. To quantitatively assess change in synchronous activity at SLA onset, we estimated the entropy of the single cell's spike trains and subdivided this measure into network burst-related information and noise-related entropy. The burst-related information was not significantly altered at the onset of NMDA-evoked SLA and slightly increased when evoked with bicuculline. The signal-to-noise ratio determined from the entropy estimates showed a significant decrease (instead of an expected increase) during SLA. We conclude that the increased population activity during the SLA is attributed to recruitment of neurons rather than to increased synchrony of each of the individual elements. 相似文献
66.
James Cassidy Martin A. Graham Wim Ten Bokkel Huinink Cathy McDaniel Albert Setanoians Elaine M. Rankin David J. Kerr Stanley B. Kaye 《Cancer chemotherapy and pharmacology》1993,31(5):395-400
Summary LL-D491941 is a new cytotoxic antibiotic selected for clinical phase I study because of its impressive pre-clinical anti-tumour activity and its low toxicity profile in experimental animals. A total of 15 patients were treated in centres in Glasgow and Amsterdam at doses ranging from 0.25 to 4 mg/m2. One minor response was noted in a patient with colonic carcinoma. The study was suspended following the discovery of unexpected cardiotoxicity. As this toxicity was not consistent with the standard (EORTC) European Organisation for Research and Treatment of Cancer toxicology profile, we chose to investigate the pharmacokinetics of LL-D491941 in mice and humans in more detail to try to explain this phenomenon. A major difference in plasma protein binding was discovered between mice and patients, with a suggestion of non-linear kinetics being noted at higher doses in humans. It is likely that these differences in drug handling account for the unexpected and serious toxicity encountered in this trial. 相似文献
67.
Comparison of non-invasive approaches to red marrow dosimetry for radiolabelled monoclonal antibodies 总被引:1,自引:0,他引:1
Marian A. B. D. Plaizier Jan C. Roos Gerrit J. J. Teule Erik B. van Dieren Wim den Hollander Hidde J. Haisma Robert L. DeJager Arthur van Lingen 《European journal of nuclear medicine and molecular imaging》1994,21(3):216-222
Red marrow is usually the dose-limiting organ during radioimmunotherapy. Several non-invasive approaches to calculate the red marrow dose have been proposed. We compared four approaches to analyse the differences in calculated red marrow doses. The data were obtained from immunoscintigraphy of two antibodies with different red marrow kinetics [iodine-131-16.88 IgM and indium- 111-OV-TL-3 F(ab)2]. The approaches are based on, respectively, homogeneously distributed activity in the body, a red marrow-blood activity concentration ratio of 0.3, scintigraphic quantification, and a combination of the second and third approaches. This fourth approach may be more adequate because of its independence from the chosen antibody. In addition, the influence of activity accumulation in liver, kidneys or cancellous bone on red marrow dose was studied. The calculated red marrow dose varied between 0.14 and 0.42 mGy/MBq for 111 In-OV TL-3 and between 0.13 and 0.68 mGy/MBq for 131I-16-88. If the radiopharmaceutical shows high affinity for cancellous bone or another organ situated near the red marrow, the activity in these organs must be included in dose calculations. This study shows a large variation in calculated red marrow dose and selection of the definitive non-invasive approach awaits validation.
Correspondence to: M.A.B.D. Plaizier 相似文献
68.
Gerald W. Lucassen Lars O. Svaasand Wim Verkruysse Martin J. C. van Gemert 《Lasers in medical science》1995,10(4):231-234
Monte Carlo simulation of laser energy deposition in a port-wine stain (PWS) skin model and numerical solution of the thermal diffusion equation have been used to calculate threshold energies for thermal injury of PWS blood vessels for different vessel sizes and laser pulse durations. It has been assumed that an average vessel temperature rise of 65 C causes thermal injury to the blood vessel. The result is that for a certain combination of wavelength, pulse duration and incident energy density, only a limited range of blood vessel sizes can be injured optimally. Higher energy densities are required to injure smaller vessels with the same pulse duration, spot size and wavelength. This gives support to the mechanisms of selective photothermolysis suggested previously by Anderson and Parrish, although their model was based on the cooling behaviour of instantaneously heated vessels. The authors hypothesize that different laser parameter settings that match the individual PWS vessel anatomy during treatment will be used in the future, instead of many treatments with the same laser parameters. This could lead to less treatment sessions and to an improved predictability of clinical results. 相似文献
69.
Ormrod D Spencer CM 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》1999,11(6):431-438
black triangle Levosalbutamol is a chirally pure beta(2)-adrenoceptor agonist developed from racemic salbutamol. black triangle The therapeutically inactive (S)-enantiomer in racemic salbutamol may be associated with increased airway hyperreactivity in patients with asthma. Levosalbutamol aims to provide equivalent control of symptoms to salbutamol but without this potential unfavourable effect. black triangle The pharmacodynamic and pharmacokinetic profiles of levosalbutamol were similar to those of racemic salbutamol and no additional effects were reported. Levosalbutamol was bronchoprotective following a methacholine challenge. black triangle A large clinical study demonstrated that inhaled levosalbutamol, 0.625mg or 1.25mg 3 times daily, provided effective relief from the symptoms of asthma. Levosalbutamol 0.625mg was at least as effective as racemic salbutamol 2.5mg. black triangle Levosalbutamol was well tolerated in clinical trials and the risk/benefit ratio was reported to be superior to that of racemic salbutamol. 相似文献
70.
Wim P.J. Witjes Michel J. A.M. De Wildt Peter F.W.M. Rosier Christine T.M. Caris Frans M.J. Debruyne Jean J.M.C.H. De La Rosette 《The Journal of urology》1996,156(3):1026-1034