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61.
Tibor T. Glant Katalin Mikecz Artin Arzoumanian A. Robin Poole 《Arthritis \u0026amp; Rheumatology》1987,30(2):201-212
Immunization with chondroitinase ABC–digested fetal human cartilage proteoglycan and Freund's complete adjuvant induced polyarthritis and ankylosing spondylitis in female BALB/c mice. The initial external symptoms of the joint inflammation were swelling and redness. This was associated with edema of the synovium and periarticular tissues and gross proliferation of cells, which reached a peak during weeks 7–9 of the experiment. Mononuclear cell infiltration, with perivascular concentration and occlusion of small vessels, was common. Synovitis increased in severity, villous pannus developed, and erosions of bone, articular cartilage, and occasionally, growth plate were observed. The lumbar spine and the proximal intervertebral discs of the tail also exhibited inflammatory and degenerative changes. As the arthritis progressed, sometimes with acute inflammatory exacerbations, more joints became involved and, by the sixteenth to the twentieth weeks of the experiment, a progressive polyarthritis, with gross joint deformities and restricted function, developed in the majority of the limb joints. Clinical and morphologic features of the disease correlated well with radiologic analysis and with an increased deposition of 99mTc–methylene diphosphonate (determined by radionuclide imaging). The development of this arthritis was accompanied by the expression of cell-mediated and humoral immunity to the immunizing antigen. However, this immunity was also observed, although it was generally less well developed, in mice that received the intact or digested proteoglycan without adjuvant. These mice did not usually develop arthritis. Control mice that received only adjuvant did not develop arthritis. 相似文献
62.
63.
Aberrations in the control of quadriceps muscle force in patients with knee osteoarthritis 总被引:10,自引:0,他引:10
OBJECTIVE: To characterize the distribution of error in knee joint proprioception, quadriceps force accuracy and steadiness, and muscle strength in patients with knee osteoarthritis (OA). Special attention was paid to eccentric strength. METHODS: We compared knee OA patients (n=20: 15 women, 5 men) with age- and sex-matched, symptom-free adults. Knee pain and mobility were assessed with standard tests. Knee joint proprioception was measured with a repositioning test. Quadriceps force accuracy and steadiness were determined during a force target-tracking task. Maximal voluntary quadriceps force was measured during eccentric, isometric, and concentric contractions. RESULTS: OA patients had knee pain, needed 67% more time to complete 4 functional tasks, and produced 82% more proprioception errors (all P < 0.05). About 80% of this error was due to overshooting the target and 68% of the overshooting error occurred at 2 of the 5 least flexed knee joint positions. OA patients had 89% more errors in accurately matching target forces during submaximal quadriceps contractions and in the same tasks, OA patients also produced these forces with 155% more variability (all P < 0.05). OA patients had especially weakened ability to produce maximal voluntary eccentric strength. CONCLUSION: Quadriceps dysfunction in knee OA includes impaired proprioception, especially in the more extended knee joint positions; impaired ability to accurately and steadily control submaximal force; and impaired eccentric strength. These results have implications for designing exercise and rehabilitation programs for patients with knee OA. 相似文献
64.
Prevention of type I diabetes transfer by glutamic acid decarboxylase 65 peptide 206-220-specific T cells 总被引:1,自引:0,他引:1 下载免费PDF全文
Kim SK Tarbell KV Sanna M Vadeboncoeur M Warganich T Lee M Davis M McDevitt HO 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(39):14204-14209
Glutamic acid decarboxylase (GAD) 65 is one of the major pancreatic antigens targeted by self-reactive T cells in type I diabetes mellitus. T cells specific for GAD65 are among the first to enter inflamed islets and may be important for the initiation of autoimmune diabetes. However, we previously reported that nonobese diabetic (NOD) mice transgenic for a T cell antigen receptor (TCR) specific for one of the immunodominant epitopes of GAD65, peptide 286-300 (G286), are protected from insulitis and diabetes. To examine whether other GAD65-reactive T cells share this phenotype, we have generated TCR transgenic NOD mice for a second immunodominant epitope of GAD65, peptide 206-220 (G206). As in G286 mice, G206 mice do not develop islet inflammation or diabetes. When adoptively transferred along with diabetogenic T cells, activated G206 T cells significantly delayed the onset of diabetes in NOD.scid recipients. Both G206 and G286 T cells produce immunoregulatory cytokines IFN-gamma and IL-10 at low levels when activated by cognate antigens. These data suggest that GAD65-specific T cells may play a protective role in diabetes pathogenesis by regulating pathogenic T cell responses. A better understanding of the functions of autoreactive T cells in type I diabetes will be necessary for choosing desirable targets for immunotherapy. 相似文献
65.
Comparison of pre‐ and post‐transplant sun‐safe behavior of kidney transplant recipients: What is needed to improve? 下载免费PDF全文
66.
Human milk contains elements that block binding of noroviruses to human histo-blood group antigens in saliva 总被引:4,自引:0,他引:4
Jiang X Huang P Zhong W Tan M Farkas T Morrow AL Newburg DS Ruiz-Palacios GM Pickering LK 《The Journal of infectious diseases》2004,190(10):1850-1859
Noroviruses (NVs) recognize human histo-blood group antigens (HBGAs) as receptors. We characterized the interaction of human milk samples with recombinant virus-like particles representing VA387, Norwalk, VA207, and MOH. Milk samples from 60 healthy women were tested for human HBGAs and for their ability to block the binding of NVs. Fifty-four women were secretors (Se+), and 6 were nonsecretors (Se-). No women had detectable A or B antigens in their milk samples. All 54 Se+ milk samples, but 0 of 6 Se- milk samples, blocked VA387 and Norwalk virus (Se+ binders) from binding to saliva samples. All 6 Lewis-positive Se- milk samples blocked binding to VA207, and variable blocking activities were exhibited by the Se+ milk samples. No milk samples blocked the binding of MOH to A and B antigens. Secretor and Lewis, but not A or B antigens, were present in human milk and were responsible for blocking NV binding to receptors and therefore are likely to be decoy receptors that protect breast-fed infants from NV infection. 相似文献
67.
Nam Michael Tran-Cong Attila Mndi Tibor Kurtn Werner E. G. Müller Rainer Kalscheuer Wenhan Lin Zhen Liu Peter Proksch 《RSC advances》2019,9(47):27279
The endophytic fungus Trichocladium sp. isolated from roots of Houttuynia cordata was cultured on solid rice medium, yielding a new amidepsine derivative (1) and a new reduced spiro azaphilone derivative (3) together with eight known compounds (4–11). Co-cultivation of Trichocladium sp. with Bacillus subtilis resulted in induction of a further new compound (2) and a 10-fold increase of 11 compared to the axenic fungal culture. Moreover, when the fungus was cultivated on peas instead of rice, a new sesquiterpene derivative (13) and two known compounds (12 and 14) were obtained. Addition of 2% tryptophan to rice medium led to the isolation of a new bismacrolactone (15). The structures of the new compounds were elucidated by HRESIMS, 1D and 2D NMR as well as by comparison with the literature. A combination of TDDFT-ECD, TDDFT-SOR, DFT-VCD and DFT-NMR calculations were applied to determine the absolute and relative configurations of 13 and 15. Compounds 7, 11 and 15 exhibited strong cytotoxicity against the L5178Y mouse lymphoma cell line with IC50 values of 0.3, 0.5 and 0.2 μM, respectively.The endophytic fungus Trichocladium sp. isolated from roots of Houttuynia cordata yielded fifteen compounds including five new ones through OSMAC and co-cultivation approaches. 相似文献
68.
Endothelial amine oxidase AOC3 transiently contributes to adaptive immune responses in the airways 下载免费PDF全文
Markus Ollert Helmut Fuchs Valerie Gailus‐Durner Martin Hrabě de Angelis Sirpa Jalkanen Tibor Z. Veres 《European journal of immunology》2014,44(11):3232-3239
Amine oxidase, copper containing 3 (AOC3, also known as vascular adhesion protein‐1 (VAP‐1)) is an endothelial adhesion molecule that contributes to the extravasation of neutrophils, macrophages, and lymphocytes to sites of inflammation. However, the role of AOC3/VAP‐1 in allergic responses remains unknown. Here, we studied eosinophil and CD4+ T‐cell recruitment to the airways using AOC3/VAP‐1‐deficient mice. In an OVA‐triggered asthma model, AOC3/VAP‐1 slightly contributed to the accumulation of leukocytes in lungs in an age‐dependent manner. We then established a new model to kinetically measure recruitment of OVA‐specific CD4+ T cells to different airway immune compartments during the priming and effector phases of an adaptive immune response. The results showed that in the absence of AOC3/VAP‐1, recruitment of antigen‐specific CD4+ T cells to draining bronchial lymph nodes is reduced by 89% on day 3 after tracheal allergen exposure, but this difference was not observed on day 6. The dispersal of effector cells to lung and tracheal mucosa is AOC3/VAP‐1 independent. Thus, in allergic airway reactions, AOC3/VAP‐1 transiently contributes to the antigen‐specific, CD4+ T‐cell traffic to secondary lymphatic tissues, but not to airway mucosa or lung parenchyma. Our results suggest a largely redundant function for AOC3/VAP‐1 in allergic inflammatory responses of the airways. 相似文献
69.
Coeli M. B. Lopes Tibor Rohács Gábor Czirják Tamás Balla Péter Enyedi Diomedes E. Logothetis 《The Journal of physiology》2005,564(1):117-129
Two-pore (2-P) domain potassium channels are implicated in the control of the resting membrane potential, hormonal secretion, and the amplitude, frequency and duration of the action potential. These channels are strongly regulated by hormones and neurotransmitters. Little is known, however, about the mechanism underlying their regulation. Here we show that phosphatidylinositol 4,5-bisphosphate (PIP2 ) gating underlies several aspects of 2-P channel regulation. Our results demonstrate that all four 2-P channels tested, TASK1, TASK3, TREK1 and TRAAK are activated by PIP2 . We show that mechanical stimulation may promote PIP2 activation of TRAAK channels. For TREK1, TASK1 and TASK3 channels, PIP2 hydrolysis underlies inhibition by several agonists. The kinetics of inhibition by the PIP2 scavenger polylysine, and the inhibition by the phosphatidylinositol 4-kinase inhibitor wortmannin correlated with the level of agonist-induced inhibition. This finding suggests that the strength of channel PIP2 interactions determines the extent of PLC-induced inhibition. Finally, we show that PIP2 hydrolysis modulates voltage dependence of TREK1 channels and the unrelated voltage-dependent KCNQ1 channels. Our results suggest that PIP2 is a common gating molecule for K+ channel families despite their distinct structures and physiological properties. 相似文献
70.
Kerényi M Allison HE Bátai I Sonnevend A Emödy L Plaveczky N Pál T 《Journal of clinical microbiology》2005,43(6):2965-2968
The association of a hemolytic phenotype with the carriage of the alpha-hemolysin gene (hlyA) and/or the silent hemolysin gene (sheA or clyA) among 540 extraintestinal clinical isolates of Escherichia coli and 110 fecal isolates from healthy individuals was investigated. Though HlyA is an important virulence factor in extraintestinal E. coli infection, the role of SheA is not completely clarified. Two hemolytic sheA+ E. coli strains that lacked hlyA and possessed no other hemolysin genes were identified. No hlyA+ sheA+ strains were identified, suggesting that there is possible incompatibility between hlyA and sheA in the chromosome of E. coli. 相似文献