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21.
Lymphocytes infiltrating the CNS during inflammation display a distinctive phenotype and bind to VCAM-1 but not to MAdCAM-1 总被引:3,自引:0,他引:3
Engelhardt Britta; Conley Frances K.; Kilshaw Peter J.; Butcher Eugene C. 《International immunology》1995,7(3):481-491
The nature of inflammatory lymphocytes recruited to the CNShas been studied in a model of chronic inflammation. Injectionof killed Corynebacterlum parvum into the cortex of the mousebrain produces a circumscribed inflammatory cellular infiltratearound the injection site, and recruited mononuclear inflammatorycells (IC) can be isolated for flow cytometric analysis. Themajority of IC were T cells. In comparison with the predominantnaive population of mesenteric lymph node T cells, IC T cellsexpress much higher levels of CD44, LFA-1 and ICAM-1, and lowerlevels of CD45RB, features commonly associated with memory (previouslyactivated) cells. In addition, in contrast to the L-selectin+6-integrinlow phenotype of naive lymph node T cells, IC T cellslacked L-selectin and were 6-integrin–. Mac-1, recentlyproposed as another marker of memory T cell differentation,was not displayed by IC T cells, suggesting that Mac-1 expressionmay be heterogeneous among memory T cell subsets. A subset ofmesenteric lymph node (MLN) T cells, probably representing activatedT cells undergoing the naive to memory transition, but not ofIC T cells, expressed high levels of 6-, ß7- and E-integrin.IC and MLN naive T cells expressed comparable levels of 4-integrin,but IC T cells stain poorly with anti-ß7 mAbs andwith mAb DATK 32, specific for the 4ß7 heterodimericlymphocyte homing receptor for the mucosal addressin MAdCAM-1,suggesting that these inflammatory cells express more 4ß1than 4ß7. Consistent with this, in in vitro adhesionassays, brain IC bound better than MLN cells to the 4ß1integrin ligand VCAM-1 and the LFA-1 ligand ICAM-1 but adheredvery poorly to the 4ß7 ligand MAdCAM-1. These findingsare consistent with and extend previous immunohistological studiesof T cells in murine experimental autoimmune encephalomyelitis,and demonstrate a distinctive phenotype for lymphocytes beingpresent in the chronically inflamed brain. 相似文献
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Kristina Elfhag Stephan R?ssner Britta Barkeling P?l Rooth 《Pharmacological research》2005,51(2):159-163
The aim of the study was to study the role of initial eating behaviour for subsequent weight loss in treatment with sibutramine (Reductil, Meridia) an anti-obesity drug enhancing satiety, and also to assess changes in mood during the treatment. The participants were 36 obese patients with a mean BMI of 39 kg m(-2). Eating behaviour was assessed with the three factor eating questionnaire (TFEQ), and depressive features with the comprehensive psychopathological rating scale (CPRS). Sibutramine (15 mg) was administered daily. The TFEQ restraint scale was negatively related to 6 months weight loss. In particular, strategic dieting behaviour and a more controlled attitude towards self-regulation were negatively related to weight loss. A positive non-placebo controlled change in mood was found already after 2 months treatment. The changes in mood were not related to the weight loss. Patients with more unrestrained eating seem to have reduced their amount of food intake more radically with enhanced satiety, manifested by greater weight loss. Physiologically enhanced satiety could have the greatest weight loss effect for patients whose eating is more governed by hunger drives and appetite rather that by conscious efforts and cognitive control. 相似文献
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Matthias Frank Holger Schönekeß Jörg Herbst Hans-Georg Staats Axel Ekkernkamp Thanh Tien Nguyen Britta Bockholdt 《International journal of legal medicine》2014,128(2):303-308
Medical literature abounds with reports on injuries and fatalities caused by airgun projectiles. While round balls or diabolo pellets have been the standard projectiles for airguns for decades, today, there are a large number of different airgun projectiles available. A very uncommon — and until now unique — discarding sabot airgun projectile (Sussex Sabo Bullet) was introduced into the market in the 1980s. The projectile, available in 0.177 (4.5 mm) and 0.22 (5.5 mm) caliber, consists of a plastic sabot cup surrounding a subcaliber copper-coated lead projectile in typical bullet shape. Following the typical principle of a discarding sabot projectile, the lightweight sabot is supposed to quickly loose velocity and to fall to the ground downrange while the bullet continues on target. These sabot-loaded projectiles are of special forensic interest due to their non-traceability and ballistic parameters. Therefore, it is the aim of this work to investigate the ballistic performance of these sabot airgun projectiles by high-speed video analyses and by measurement of the kinetic parameters of the projectile parts by a transient recording system as well as observing their physical features after being fired. While the sabot principle worked properly in high-energy airguns (E?>?17 J), separation of the core projectile from the sabot cup was also observed when discharged in low-energy airguns (E?<?7.5 J). While the velocity of the discarded Sussex Sabo core projectile was very close to the velocity of a diabolo-type reference projectile (RWS Meisterkugel), energy density was up to 60 % higher. To conclude, this work is the first study to demonstrate the regular function of this uncommon type of airgun projectile. 相似文献
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In systemic sclerosis, microvascular injury often precedes the development of fibrosis. Whereas the development of digital ulcers and skin fibrosis causes high morbidity, the affection of internal organs, in particular complications such as interstitial lung disease and pulmonary (arterial) hypertension, account for the high disease-associated mortality of these patients. Vascular animal models of systemic sclerosis are of utmost importance to study pathophysiological aspects, to identify molecular key players, and to perform interventional proof of concept-studies. So far, animal models of systemic sclerosis have mainly reflected the pro-fibrotic features of the human disease. The Fra-2 (Fos-related antigen-2) transgenic mouse model simultaneously displays both pro-fibrotic and vascular characteristics of human systemic sclerosis. 相似文献
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During multiple sclerosis or its animal model, experimental autoimmune encephalomyelitis, circulating immune cells enter the central nervous system (CNS) causing neuroinflammation. Extravasation from the blood circulation across the vessel wall occurs through a multistep process regulated by adhesion and signal transducing molecules on the immune cells and on the endothelium. Since the CNS is shielded by the highly specialized blood-brain barrier (BBB), immune cell extravasation into the CNS requires breaching this particularly tight endothelial border. Consequently, travelling into the CNS demands unique adaptations which account for the extreme tightness of the BBB. Modern imaging tools have shown that after arresting on BBB endothelium, in vivo or in vitro encephalitogenic effector/memory T cells crawl for long distances, possibly exceeding 150 μm along the surface of the BBB endothelium before rapidly crossing the BBB. Interestingly, in addition to the distance of crawling, the preferred direction of crawling against the flow is unique for T cell crawling on the luminal surface of CNS microvessels. In this review, we will summarize the cellular and molecular mechanisms involved in the unique T cell behavior that is obviously required for finding a site permissive for diapedesis across the unique vascular bed of the BBB. 相似文献
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Green JB Fricke B Chetty MC von Düring M Preston GF Stewart GW 《Blood cells, molecules & diseases》2004,32(3):411-422
The 32kD membrane protein stomatin was first studied because it is deficient from the red cell membrane in two forms of the class of haemolytic anaemias known as "hereditary stomatocytosis." The hallmark of these conditions is a plasma membrane leak to the monovalent cations Na+ and K+: the protein is missing only in the most severely leaky of these conditions. No mutation has ever been found in the stomatin gene in these conditions. Stomatin-like proteins have been identified in all three domains of biology, yet their function remains enigmatic. Although the murine knock-out is without phenotype, we have identified a family showing a splicing defect in the stomatin mRNA, in which affected children showed a catastrophic multisystem disease not inconsistent with the now-known wide tissue distribution of stomatin. We report here a study of strongly homologous stomatin-like genes in prokaryotes, which reveals a close connection with a never-studied gene erroneously known as "nfed." This gene codes for a hydrophobic protein with a probable serine protease motif. It is possible that these stomatin-like genes and those which are known as"nfed" form an operon, suggesting that the two protein products are aimed at a common function. The corollary is that stomatin could be a partner protein for a membrane-bound proteolytic process, in both prokaryotes and in eukaryotes generally: this idea is consistent with experimental evidence. 相似文献
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