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41.
The characteristics of synovial fluid obtained from 3 patients with drug-induced lupus erythematosus are described. Two patients had "inflammatory" counts of synovial leukocytes, in the range of 2,500-39,000/mm3, with mononuclear predominance in 1 patient and neutrophil predominance in the other. The third patient had "noninflammatory" fluid, with mononuclear predominance. Lupus erythematosus cells formed in vivo were observed in the synovial fluid of 2 of the patients. Biopsy of the synovium of 1 patient showed nonspecific chronic inflammatory changes. Our findings in these patients with drug-induced lupus are indistinguishable from those previously described in patients with idiopathic lupus erythematosus. 相似文献
42.
43.
Diehl P Hantke B Hennig M Tschesche H Mittelmeier W Schmitt M Muehlenweg B 《International journal of molecular medicine》2004,13(5):711-715
Matrix metalloproteinase 13 (MMP-13), urokinase type plasminogen activator (uPA), and plasminogen activator inhibitor type-1 (PAI-1) have been reported to be involved in aseptic loosening of artificial hip joints. This study for the first time presents the protein levels of all of these factors in synovial-like interfaces between bone and prosthesis and in pseudocapsular tissues surrounding the artificial joint in patients with aseptic loosening (n=17) measured by ELISA. No differences were observed in the antigen expression of MMP-13, uPA, and PAI-1, comparing interface and pseudocapsular tissue. Also, no significant correlation between the protein expression of these factors and years from arthroplasty to revision or to type of fixation (cemented vs. cementless) was observed. As control, MMP-13, uPA, and PAI-1 antigen levels were also determined in the synovium of patients with osteoarthritis (n=10). Yet, the antigen levels of MMP-13, uPA, and PAI-1 in tissue specimens from patients with aseptic loosening of artificial hip joints were significantly higher compared to their expression in synovial capsular tissues obtained from patients with osteoarthritis. In conclusion, this study shows that elevated protein levels of uPA, PAI-1, and MMP-13 in periprosthetic pseudocapsular and interface tissues from patients after total hip replacement due to aseptic loosening seem not to be associated with the patient outcome. 相似文献
44.
Adolf Dörge Franz X. Beck Roger Rick Wolfram Nagel Klaus Thurau 《Pflügers Archiv : European journal of physiology》1990,416(3):335-338
The role of mitochondria-rich cells (MR cells) in transepithelial Na transport was investigated by determining electrolyte concentrations and Rb uptake in individual cells of frog skin epithelium using electron microprobe analysis. Measurements were performed under control conditions and after blocking the transepithelial Na transport with amiloride. Under control conditions, Na and Cl concentrations of MR cells scattered much more than those of principal cells and ranged from a few up to more than 30 mmol/kg wet weight. Rb uptake from the basal side into individual MR cells also showed a large variation and was, on the average, much less pronounced than into the principal cells. In principal cells, amiloride reduced the Na concentration and Rb accumulation. In contrast, no effect was observed upon electrolyte concentration and Rb uptake of MR cells. Rb uptake was correlated to the Na concentration of MR cells both under control conditions and after amiloride. It is concluded that, in contrast to the principal cells, MR cells are not involved in amiloride-sensitive transepithelial Na transport and that their Na/K-pump activity is very low. 相似文献
45.
Automated extraction of genomic DNA from medically important yeast species and filamentous fungi by using the MagNA Pure LC system 总被引:5,自引:0,他引:5
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Loeffler J Schmidt K Hebart H Schumacher U Einsele H 《Journal of clinical microbiology》2002,40(6):2240-2243
A fully automated assay was established for the extraction of DNA from clinically important fungi by using the MagNA Pure LC instrument. The test was evaluated by DNA isolation from 23 species of yeast and filamentous fungi and by extractions (n = 28) of serially diluted Aspergillus fumigatus conidia (10(5) to 0 CFU/ml). Additionally, DNA from 67 clinical specimens was extracted and compared to the manual protocol. The detection limit of the MagNA Pure LC assay of 10 CFU corresponded to the sensitivity when DNA was extracted manually; in 9 of 28 runs, we could achieve a higher sensitivity of 1 CFU/ml blood, which was found to be significant (p 相似文献
46.
The Arabidopsis det3 mutant reveals a central role for the vacuolar H(+)-ATPase in plant growth and development 总被引:1,自引:0,他引:1
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Schumacher K Vafeados D McCarthy M Sze H Wilkins T Chory J 《Genes & development》1999,13(24):3259-3270
In all multicellular organisms growth and morphogenesis must be coordinated, but for higher plants, this is of particular importance because the timing of organogenesis is not fixed but occurs in response to environmental constraints. One particularly dramatic developmental juncture is the response of dicotyledonous seedlings to light. The det3 mutant of Arabidopsis develops morphologically as a light-grown plant even when it is grown in the dark. In addition, it shows organ-specific defects in cell elongation and has a reduced response to brassinosteroids (BRs). We have isolated the DET3 gene by positional cloning and provide functional and biochemical evidence that it encodes subunit C of the vacuolar H(+)-ATPase (V-ATPase). We show that the hypocotyl elongation defect in the det3 mutant is conditional and provide evidence that this is due to an alternative mechanism of V-ATPase assembly. Together with the expression pattern of the DET3 gene revealed by GFP fluorescence, our data provide in vivo evidence for a role for the V-ATPase in the control of cell elongation and in the regulation of meristem activity. 相似文献
47.
Prof. Dr. C. -P. Sodomann G. Maerker-Alzer K. Havemann C. Dienst H. Schultz D. Mitrenga K. Schumacher G. A. Martini 《Journal of molecular medicine (Berlin, Germany)》1979,57(17):893-903
Summary It is a clinically and experimentally well supported working hypothesis that infection with hepatitis B virus may result in chronic active hepatitis in patients with suspected immune deficiencies. On this basis, a pilot study was performed in order to evaluate the effect of specific transfer factor (TF) in the treatment of HBs-Ag-positive chronic active hepatitis. From the leukocytes of 500 ml venous blood each of 40 volunteers that had completely recovered from acute virus hepatitis B within the last 6 months, a unique TF pool (40 units of TF) was prepared according to the method of Lawrence. Preexaminations indicated that this preparation was able to enhance cellular immune reactions in vitro. Thirteen patients with HBs-antigenemia and chronic active hepatitis (i.e., two liver biopsies within the last 6 or more months with the histological criteria of chronic aggressive hepatitis according to de Groote, elevated serum levels of bilirubin, alkaline phosphatase, transaminase activities, and/or -globulines) were randomized: Seven received s.c. injections of two units of TF each on days 1 and 15, the other six saline. Conversion of skin reactions to some ubiquitous antigens occurred in the TF group, but no significant and constant drop of HBs-Ag serum titers was observed. Although some of the biochemical parameters seemed to ameliorate in the TF group, the differences versus the control group did not prove to be significant within the limited number of patients under observation. The in vitro reactivity of patients' lymphocytes to HBs-Ag, tested by means of the3H-thymidine uptake, was never found enhanced after TF application. In the used doses, specific TF was not effective in the treatment of HBs-Ag-positive chronic active hepatitis; unfavorable side-effects were not observed. 相似文献
48.
Herzog BA Ott PA Dittrich MT Quast S Karulin AY Kalbacher H Karges W Tary-Lehmann M Lehmann PV Boehm BO Durinovic-Belló I 《Journal of autoimmunity》2004,23(1):45-54
Active T cell recognition of islet antigens has been postulated as the pathogenic mechanism in human type 1 diabetes, but evidence is scarce. If T cells are engaged, they are expected to display increased clonal size and exhibit a T helper (Th)1/Th2 differentiation state. We used a peptide library that covers tyrosine phosphatase IA-2, a target antigen expressed in pancreatic beta cells, to probe 8 diabetic patients and 5 HLA-matched controls. When tested in a high resolution IFNgamma/IL-4 double color ELISPOT assay directly ex vivo, the number of IA-2-reactive IFNgamma producing cells was 17-fold higher in patients than in controls and IL-4 producing cells were not present. An average of 9 peptides was recognized in the patients vs. one in the controls. Determinant recognition primarily involved CD4+ cells and showed high variability among the patients. Furthermore, anti-CD28 antibody signal enhances quantitative assessment of effector T cells in T1D patients. In vitro expansion with peptides and IL-2 results in detection of responding cells in the controls and loss of disease specificity of the T cell response. Together these data provide strong evidence for the active targeting of IA-2 by Th1 memory effector cells in human type 1 diabetes. 相似文献
49.
Depolarization-induced retrograde synaptic inhibition in the mouse cerebellar cortex is mediated by 2-arachidonoylglycerol 总被引:3,自引:0,他引:3
Bela Szabo Michal J. Urbanski Tiziana Bisogno Vincenzo Di Marzo Aitziber Mendiguren Wolfram U. Baer Ilka Freiman 《The Journal of physiology》2006,577(1):263-280
Endocannabinoids acting on CB1 cannabinoid receptors are involved in short- and long-term depression of synaptic transmission. The aim of the present study was to determine which endocannabinoid, anandamide or 2-arachidonoylglycerol (2-AG), is involved in depolarization-induced suppression of inhibition (DSI) in the cerebellar cortex, which is the most widely studied form of short-term depression. Depolarization of Purkinje cells in the mouse cerebellum led to an increase in intracellular calcium concentration and to suppression of the inhibitory input to these neurons (i.e. DSI occurred). Orlistat and RHC80267, two blockers of sn -1-diacylglycerol lipase, the enzyme catalysing 2-AG formation, abolished DSI by acting downstream of calcium influx. In contrast, DSI occurred also in the presence of a phospholipase C inhibitor. Intact operation of the calcium-dependent messengers calmodulin and Ca2+ –calmodulin-dependent protein kinase II were necessary for DSI. DSI was potentiated by an inhibitor of the main 2-AG-degrading enzyme, monoacylglycerol lipase. Interference with the anandamide metabolizing enzyme, fatty acid amide hydrolase, did not modify DSI. Thus, three kinds of observations identified 2-AG as the endocannabinoid involved in DSI in the mouse cerebellum: DSI was abolished by diacylglycerol lipase inhibitors; DSI was potentiated by a monoglyceride lipase inhibitor; and DSI was not changed by an inhibitor of fatty acid amide hydrolase. Further experiments indicated that 2-AG is the endocannabinoid mediating short-term retrograde signalling also at other synapses: orlistat abolished DSI in the rat cerebellum, DSI in the mouse substantia nigra pars reticulata and depolarization-induced suppression of excitation in the mouse cerebellum. 相似文献
50.
Heparin-binding fragments of fibronectin are potent inhibitors of endothelial cell growth. 总被引:7,自引:1,他引:7
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G. A. Homandberg J. E. Williams D. Grant B. Schumacher R. Eisenstein 《The American journal of pathology》1985,120(3):327-332
Two heparin-binding proteolytic fragments of fibronectin--an amino-terminal 29-kd segment and a carboxyl-terminal 40-kd segment-are apparently specific, potent inhibitors of the growth of cultured bovine aortic endothelial cells and inhibit growth in a reversible, dose-dependent manner. In contrast, native fibronectin at higher dosages neither inhibits nor interferes with the effects of the 29-kd fragment. The data, therefore, suggest that fibronectin fragments may participate in the regulation of vascular growth. 相似文献