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31.
Wolschrijn CF Kik MJ Weijs WA 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,275(1):990-996
The present study describes cartilage-free areas on the ulnar trochlear notch and the humeral condyle of eight very young golden retrievers with otherwise healthy elbow joints. Remarkably, the youngest dog with full-thickness cartilage-free areas was only 8 weeks old. The younger dogs showed no macroscopic abnormalities on the locations that were affected in the older dogs. Two kinds of cartilage modifications were found. Cartilage-free areas at the edges of the articular cartilage layer were present on the humeral capitulum and on two locations of the ulna, (the medial and lateral at the base of the anconeal process, and the trochlear notch near the lateral coronoid process, which was fractured in two cases). Histological examination showed that these cartilage-free areas were filled with dense supportive tissue. Synovial cells covered this tissue as well as the surrounding hyaline cartilage. The synovial membrane covering the areas was macroscopically enlarged, but histological examination revealed no signs of inflammation. The second type of modification consisted of discoloration of the articular surface at the humeral trochlea. Histological examination revealed that in this area the articular surface was composed of fibrocartilage instead of hyaline cartilage. Apparently, there are locations within the elbow joint in which articular cartilage is not necessary for normal joint functioning. The presence of fibrocartilage on the articular surface of the humeral condyle is a surprising finding, for which no explanation has yet been found. 相似文献
32.
Wim H. J. P. Linssen Martin J. Van den Bent Han G. Brunner Petra J. E. Poels 《American journal of medical genetics. Part A》1994,51(1):81-82
We report on 3 sibs (2 males and one female) with sensorineural deafness. The presence of ovarian dysgenesis in the girl suggested a diagnosis of Perrault syndrome. In addition our patients have a sensory polyneuropathy and amelogenesis imperfecta. Two of the patients have mild mental retardation, fine choreatic movements, and dyspraxia. It is discussed whether these findings are part of a separate clinical entity or should be included within the spectrum of the Perrault syndrome. © 1994 Wiley-Liss, Inc. 相似文献
33.
Differential expression of FIZZ1 and Ym1 in alternatively versus classically activated macrophages 总被引:10,自引:0,他引:10
Raes G De Baetselier P Noël W Beschin A Brombacher F Hassanzadeh Gh G 《Journal of leukocyte biology》2002,71(4):597-602
Alternatively activated macrophages (aaMphi) display molecular and biological characteristics that differ from those of classically activated macrophages (caMphi). Recently, we described an experimental model of murine trypanosomosis in which the early stage of infection of mice with a Trypanosoma brucei brucei variant is characterized by the development of caMphi, whereas in the late and chronic stages of infection, aaMphi develop. In the present study, we used suppression subtractive hybridization (SSH) to identify genes that are expressed differentially in aaMphi versus caMphi elicited during infection with this T. b. brucei variant. We show that FIZZ1 and Ym1 are induced strongly in in vivo- and in vitro-elicited aaMphi as compared with caMphi. Furthermore, we demonstrate that the in vivo induction of FIZZ1 and Ym1 in macrophages depends on IL-4 and that in vitro, IFN-gamma antagonizes the effect of IL-4 on the expression of FIZZ1 and Ym1. Collectively, these results open perspectives for new insights into the functional properties of aaMphi and establish FIZZ1 and Ym1 as markers for aaMphi. 相似文献
34.
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
35.
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
36.
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
37.
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
38.
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
39.
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
40.
Rooyackers OE Soeters PB Saris WH Wagenmakers AJ 《Clinical nutrition (Edinburgh, Scotland)》1995,14(2):105-115
Glutamine is considered to be a conditionally essential amino acid during critical illness and has, therefore, been advocated to be included in nutritional support supplied in these situations. We investigated whether a diet containing a protein source rich in glutamine can restore depleted glutamine pools (plasma and muscle) and counteract muscle wasting, in a rat model of critical illness (intraperitoneal injection of zymosan). A glutamine-rich protein source was obtained by mixing a wheat protein hydrolysate (25% glutamine) with a whey protein isolate (to prevent essential amino acid deficiency). Feeding healthy control rats for 2 weeks with an adequate diet containing this protein source increased the two main glutamine pools (plasma and muscle). However, no effect was observed on the following zymosan-induced changes: 1) decreased glutamine and arginine concentrations (plasma and muscle), 2) wasting of muscle protein, and 3) decreased mitochondrial content in skeletal muscle. We conclude that a diet containing a glutamine-rich protein source can be used to increase plasma and muscle glutamine concentrations in healthy rats, but is of limited value to counteract wasting of skeletal muscle in zymosan-treated rats. 相似文献