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101.
Buysmann S; Bemelman FJ; Schellekens PT; van Kooyk Y; Figdor CG; ten Berge IJ 《Blood》1996,87(1):404-411
We investigated the mechanism by which antihuman CD3 monoclonal antibodies of the isotypes IgG2a (eg, OKT3) and IgA (eg, IXA) can induce the rapid disappearance of virtually all circulating T lymphocytes. We hypothesize that upregulation of adhesion molecules on the lymphocyte membrane contributes to this effect. However, this hypothesis is difficult to test, because of the inherent lymphocytopenia and/or shifts in lymphocyte populations between intra and extra-vascular compartments. Therefore, studies in vitro were performed, as well. Analysis of peripheral blood lymphocytes isolated at several times after addition of OKT3 or IXA to whole blood of healthy individuals showed an immediate increase in the proportion of T cells expressing NKI-L16, an activation epitope on CD11a/CD18. Likewise, an increase in CD11b/CD18 expression occurred. In parallel experiments, a transiently increased adhesion of T cells to endothelial cell monolayers was observed. This adhesion could be completely blocked by anti-CD18 or anti-CD11a monoclonal antibodies and only partly by an anti-CD11b antibody. Our data indicate that upregulation of activation epitopes of CD11a/CD18, as well as increased expression of CD11b/CD18 on T lymphocytes, may result in increased adhesion of these cells to intercellular adhesion molecule-1 (ICAM-1) and ICAM-2 on vascular endothelium. This phenomenon may, at least, partly explain the rapidly occurring peripheral lymphocytopenia observed in vivo. 相似文献
102.
B lymphoblastoid cell lines with normal and defective O-glycosylation established from an individual with blood group Tn 总被引:2,自引:0,他引:2
Individuals with the Tn blood group contain terminal serine/threonine- linked N-acetylgalactosamine residues in their blood cells. This is due to lack of UDP-D-galactose: D-N-acetyl galactosamine beta-D-galactosyl transferase from part of their red cells and probably from their leukocytes. We have established B lymphoblastoid cell lines from such an individual by in vitro infection of his lymphocytes with Epstein- Barr virus. The original line contained a mixture of cells reactive and nonreactive with Helix pomatia lectin (Hp). These cells were subcloned after staining with fluorescent Hp by a fluorescence-activated cell sorter (FACS) into homogeneous, phenotypically stable lines of Hp- positive (Hp+) and Hp-negative (Hp-) cells. The molecular differences between the membrane glycoproteins were characterized by carbohydrate- specific surface labeling techniques, Hp affinity chromatography, polyacrylamide slab gel electrophoresis and glycopeptide/oligosaccharide analysis. The major O-glycosidic membrane glycoprotein (GP105) was retained on Hp-Sepharose columns only from Hp+ cells, whereas the common leukocyte antigen (GP160-200) was partially retained on Hp columns from both lines. These proteins were isolated by immune precipitation with monoclonal antibodies and characterized. The results show that the GP105 glycoprotein from Hp+ cells contains terminal N-acetylgalactosamine residues but also more complex oligosaccharides. The common leukocyte antigen showed different electrophoretic mobilities in Hp+ and Hp- cells. UDP-galactose D-N- acetyl galactosamine beta-galactosyl transferase was almost absent in the Hp+ cells. These cell lines are useful for studies on the functional role and regulation of the biosynthesis of O-glycosidic carbohydrates. 相似文献
103.
Xiaoban Xin Murilo Rodrigues Mahaa Umapathi Fabiana Kashiwabuchi Tao Ma Savalan Babapoor-Farrokhran Shuang Wang Jiadi Hu Imran Bhutto Derek S. Welsbie Elia J. Duh James T. Handa Charles G. Eberhart Gerard Lutty Gregg L. Semenza Silvia Montaner Akrit Sodhi 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(36):E3425-E3434
104.
Heiko Sailer Kei Shinoda Georgios Blatsios Konrad Kohler Lars Bondzio Eberhart Zrenner Florian Gekeler 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(8):1169-1178
Background Retinal implants are intended to replace photoreceptors in patients suffering from degenerative retinal diseases such as retinitis
pigmentosa. Data show that photodiodes in subretinal implants are not powerful enough to stimulate overlying retinal tissue
by simply transforming light energy into electrical energy. Therefore, infrared (IR) irradiation has been envisioned to supply
additional energy. While epiretinal implants mostly use induction coils for wireless energy transfer, IR irradiation seems
to be an additional option. This study investigated the feasibility of an IR energy supply for an active subretinal implant
by assessing thermal effects of IR irradiation onto the rabbit retina.
Methods Polyimide foil strips carrying an optical sensor as well as a thermal sensor were implanted into the subretinal space of the
eyes of nine rabbits using a transchoroidal surgical approach. The area of the thermal sensor was irradiated by an IR laser
(830 nm) focused on the device. The sensor provided simultaneous real-time measurements of absolute temperature and irradiation
density, allowing direct correlation of the temperature increase to different intensities of IR irradiation. Possible IR-related
damage to the retina was examined in histological sections. Temperature changes in living and dead animals were evaluated
as a function of IR irradiation power of between 0.1 mW and 40 mW (0.03 mW/mm2–12.7 mW/mm2).
Results We found an exponential relationship between IR irradiation power and temperature increase over the whole range (up to 12.7 mW/mm2) in the living animal. The maximum temperature increase caused by IR irradiation of 40 mW (12.7 mW/mm2) was 4.5°C. The ratio of temperature increase to IR irradiation density postmortem (i.e., without ocular blood flow) was
linear over the whole range, with 1.15°C per 1 mW/mm2. Thus, the cooling effect of ocular blood flow varied depending on IR irradiance density. In histological sections, no IR-induced
damage to the retina was detected.
Conclusions A temperature increase of 3.2°C in the living rabbit eye is to be expected when powering a subretinal implant with 15 mW (4.8 mW/mm2) IR power, the wattage used in an external power supply for an active implant with 1,500 electrodes. This appears to be a
tolerable increase for ocular tissue. 相似文献
105.
106.
Extranodal malignant lymphoma: detection with FDG PET versus CT 总被引:19,自引:0,他引:19
Moog F; Bangerter M; Diederichs CG; Guhlmann A; Merkle E; Frickhofen N; Reske SN 《Radiology》1998,206(2):475
107.
Stephan Kremmer Anja Eckstein Andreas Gal Eckart Apfelstedt-Sylla Heike Wedemann Klaus Rüther Eberhart Zrenuer 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1997,235(9):575-583
This report describes ocular findings obtained in four patients from three families with autosomal dominant retinitis pigmentosa (adRP) due to missense mutations in the rhodopsin gene. Phenotypes were characterized by standard ophthalmologic examinations, visual fields, electroretinography (ERG), dark adaptation, and two-color dark-adapted threshold perimetry. Two patients aged 38 and 45 years, respectively, from a family with the Cys110Phe mutation showed mild fundus changes without bone spicules as well as small arcuate scotomas in the inferior quadrants of their visual fields but displayed severe functional loss of rods and cones in the ERG. Two-color dark-adapted threshold perimetry revealed a regional type of degeneration. A 48-year-old patient with an Arg135Gly mutation had typical RP with concentrically narrowed visual fields and nondetectable ERG responses. Central visual functions were well preserved for a long time. Two-color dark-adapted threshold perimetry indicated a diffuse type of retinal degeneration. An 18-year-old patient with a GIn344stop mutation has been followed for 13 years. His ERG was clearly reduced at the age of 5 years; since that time, disease progression has been very slow. Currently, there are relatively mild alterations in visual acuity, rod sensitivity, and visual fields. Our findings confirm that there is a large phenotypic variety among patients with adRP and different rhodopsin mutations.This work was presented at the 93rd annual meeting of the Deutsche Ophthalmologische Gesellschaft, Mannheim, 23–26 September 1995 相似文献
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