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991.
Sigmundsdóttir H Johnston A Gudjónsson JE Valdimarsson H 《Clinical immunology (Orlando, Fla.)》2004,111(1):119-125
At both cutaneous and mucosal sites, interleukin (IL)-10, IL-12 and transforming growth factor (TGF)-beta are important regulators of chronic inflammatory disease, where cutaneous lymphocyte-associated antigen (CLA) and alphaE integrin (CD103) may be expressed. Stimulation with streptococcal pyrogenic exotoxin C (SpeC) increased the expression of CD103 by CD8+ but not CD4+ T cells. While adding IL-12 augmented the expression of CLA, superantigen-induced expression of CD103 was markedly suppressed by IL-12, which could be reversed by TGF-beta. Antibodies against TGF-beta inhibited, and a combination of anti-TGF-beta and IL-12 completely abrogated the induced CD103 expression. IL-10 strongly decreased the frequency of CLA+ and although not increasing the frequency of CD103+CD8+ T cells, the amount of CD103 expressed per cell was markedly increased. Thus, the expression of CLA and CD103 may be antagonistically regulated by IL-10 and IL-12 and the balance between these cytokines could influence the T cell migration of inflammatory cells into epithelial tissues. 相似文献
992.
Ishitsuka R Kobayashi T 《Anatomical science international / Japanese Association of Anatomists》2004,79(4):184-190
Sphingomyelin is a major sphingolipid species in animal cells and is a major lipid constituent of plasma membranes. Recent reports have established important roles for sphingomyelin and its metabolites as second messengers in signal transduction events during development and differentiation. Sphingomyelin is also a major component of sphingolipid, cholesterol-rich plasma membrane microdomains, known as 'lipid rafts'. However, little is known about the organization of sphingomyelin in biological membranes. Lysenin is a recently discovered sphingomyelin-specific toxin. In the present review, we summarize the current characterization of this protein and describe our recent attempt to elucidate the organization of sphingomyelin in cellular membranes using lysenin as a unique tool. 相似文献
993.
Transcranial magnetic stimulation: new insights into representational cortical plasticity 总被引:15,自引:5,他引:15
Siebner HR Rothwell J 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2003,152(1):1-16
In the last decade, transcranial magnetic stimulation (TMS) has been used increasingly as a tool to explore the mechanisms
and consequences of cortical plasticity in the intact human cortex. Because the spatial accuracy of the technique is limited,
we refer to this as plasticity at a regional level. Currently, TMS is used to explore regional reorganization in three different
ways. First, it can map changes in the pattern of connectivity within and between different cortical areas or their spinal
projections. Important examples of this approach can be found in the work on motor cortex representations following a variety
of interventions such as immobilization, skill acquisition, or stroke. Second, TMS can be used to investigate the behavioural
relevance of these changes. By applying TMS in its "virtual lesion" mode, it is possible to interfere with cortical function
and ask whether plastic reorganization within a distinct cortical area improves function. Third, TMS can be used to promote
changes in cortical function. This is achieved by using repetitive TMS (rTMS) to induce short-term functional reorganization
in the human cortex. The magnitude and the direction of rTMS-induced plasticity depend on extrinsic factors (i.e. the variables
of stimulation such as intensity, frequency, and total number of stimuli) and intrinsic factors (i.e. the functional state
of the cortex targeted by rTMS). Since conditioning effects of rTMS are not limited to the stimulated cortex but give rise
to functional changes in interconnected cortical areas, rTMS is a suitable tool to investigate plasticity within a distributed
functional network. Indeed, the lasting effects of rTMS offer new possibilities to study dynamic aspects of the pathophysiology
of a variety of diseases and may have therapeutic potential in some neuropsychiatric disorders.
Electronic Publication 相似文献
994.
It has been suggested for many years that the regulation of the immune system for the maintenance of peripheral tolerance may involve regulatory/suppressor T cells. In the past few years, several investigators have demonstrated that these cells can be generated in vitro. It has also been shown that they can inhibit the progression of various autoimmune disease models when infused into susceptible mice. We have generated two murine T cell lines in the presence of KLH-specific T cell clones from BALB/c or DBA2 mice. The lines are characterized by a low proliferative response to mitogens, the capacity to secrete high amounts of IL-10 and TGF-beta, and small amounts of IFN-gamma. Interestingly, these cells are unable to produce IL-2, IL-4 or IL-5. The study of the surface phenotype of both lines revealed CD4+, CD25high, CD44low and CTLA-4- cells. When injected intravenously in (CBy.D2) F1 mice, these cells were able to inhibit 50-100% of the TNP-specific antibody production, when the hapten was coupled to KLH. In the present study we offer another evidence for the existence of regulatory T cells in the T lymphocyte repertoire, suggesting that they can also regulate immune responses to foreign antigens. Furthermore, we demonstrate an alternative pathway to generate these cells different from approaches used thus far. 相似文献
995.
N. K. Isaev R. E. Uzbekov D. B. Zorov E. V. Stel'mashuk I. V. Viktorov 《Bulletin of experimental biology and medicine》1995,119(4):365-367
It is shown that treating rat cerebellum with glutamate in a neurocytotoxic concentration causes a drop of the mitochondrial
membrane potential in granule cells and leads to ultrastructural alterations of mitochondria in these neurons.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N
o
4, pp. 378–380, April, 1995.
Presented by the late Member of the Russian Academy of Medical Sciences 相似文献
996.
Analysis of gamma delta V region usage in normal and diseased human intestinal biopsies and peripheral blood by polymerase chain reaction (PCR) and flow cytometry. 总被引:1,自引:1,他引:1
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997.
Kazuyoshi Nishihara Masaki Takashima Toshiya Furuta Masaru Haraguchi Masazumi Tsuneyoshi 《Pathology international》1995,45(3):250-255
An 80 year old Japanese man had adenosquamous carcinoma of the gall-bladder characterized by an adenocarci-noma (AC) in the gall-bladder lumen and a squamous cell carcinoma (SCC) in the Invaded region of the liver. In the AC, the tumor cells consisted of atypical columnar epithelium with pseudostratification, mimicking gastric foveolar epithelium, while atypical signet-ting cells were scattered within the SCC. There was an abrupt transition between the AC and SCC areas. The tumor cells in the AC area were intensely positive for galactose oxidase-Schiff staining, and paradoxical concanavalin A staining revealed these tumor cells to have Class II mucins. lmmunohistochemically, the tumor cells in foveolar-type adenocarcinoma were diffusely positive for cathepsin D. Flow cytometrical analysis of DNA content showed the AC area to be diploid and the SCC area to be aneuploid. The Sphase fraction of the SCC area (46.9%) was larger than that of the AC area (19.5%). The positive rate of immunostaining for proliferating cell nuclear antigen in the SCC area (mean 50.627%) was larger than that of the AC area (mean 3.048%, P < 0.01). These resutts suggest that the AC area of this tumor, histochemically and immunohistochemically, showed gastric foveolar-type characteristics, the SCC component was squamous cell metaplasia of the preexisting AC, and that the SCC area had a greater proliferating capacity than the AC area. 相似文献
998.
Mireille Lahoud David Vremec Richard L. Boyd Ken Shortman 《Clinical & developmental immunology》1993,3(2):103-112
Thymic nurse cells (TNC), multicellular complexes consisting of lymphoid cells
enclosed within cortical epithelial cells, were isolated from mouse thymus by a modified
procedure allowing immunofluorescent labeling and flow cytometric analysis of their
lymphoid contents (TNC-L). Collagenase was the only protease used for tissue
digestion, to ensure that surface antigen markers remained intact. Zonal unit-gravity
elutriation was used to enrich the TNC on the basis of their high sedimentation rate,
followed by immunomagnetic bead depletion to remove residual mononuclear cell
contaminants and a density separation to remove debris. The TNC-L were then released
from inside TNC by a short period of culture. The measured contamination of TNC-L
with exogenous thymocytes was around 0.5%. Three-color immunofluorescent labeling
revealed that TNC-L included, as well as a maiority of immature CD4+8+3low thymocytes,
about 12% of apparently mature CD4+8-3high and CD4-8+3high thymocytes. TNC are
located in the cortex, where mature cells are rare; the occurrence of mature phenotype
cells within these structures suggests that they represent a microenvironment for the
selection and generation of mature T cells. 相似文献
999.
Detection of IgE-mediated respiratory sensitization in workers exposed to hexahydrophthalic anhydride 总被引:10,自引:0,他引:10
1000.