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981.
Gas Chromatographic-Mass Spectrometric Determination of myo-Inositol in Human Cerebrospinal Fluid 总被引:2,自引:2,他引:0
Carl-Gunnar Swahn 《Journal of neurochemistry》1985,45(2):331-334
The concentration of free myo-inositol in CSF was determined with a gas chromatographic-mass spectrometric method using deuterated myo-inositol as an internal standard after conversion to the hexa-O-acetyl derivative with acetic anhydride and pyridine. Twenty microliters of CSF is sufficient for the analysis which has a coefficient of variation of 9%. Identical analytical results were obtained on two different mass numbers. Schizophrenic patients were compared with healthy control persons. In addition, patients with rheumatoid arthritis or with neurological illnesses were studied. No consistent differences related to the illness could be found. The mean concentration of myo-inositol was about 25 micrograms/ml. Treatment of schizophrenic patients with chlorpromazine or sulpiride had no significant effect on the concentration of myo-inositol in CSF. 相似文献
982.
Polymorphonuclear leukocytes (PMNs) isolated from peripheral blood and synovial fluid of patients with rheumatoid arthritis and from peripheral blood of volunteers were stimulated with 12-Phorbol-13-myristate acetate (PMA). No significant differences in luminol-amplified chemiluminescence were found between different patients and control groups. However, two distinct patterns of native chemiluminescence were observed. Type I showed no, or only a small, increase in native chemiluminescence with integral counts over 30 min less than 3 × 105 cpm, and the majority of samples from volunteers were of this type. Type II was characterized by a burst of native chemiluminescence starting 8 to 15 min after cell stimulation. It was found in most PMN samples from patients with rheumatoid arthritis. Integral counts over 30 min were always higher than 106 cpm and as high as 108 cpm in some cases. A strong inhibition of the Type II native chemiluminescence was caused by desferal, catalase, thiourea, and glutathione. However, the luminol-amplified chemiluminescence remained unchanged or was only slightly decreased under the same experimental conditions. Sodium azide strongly inhibited both kinds of luminscence. Hydroxyl radicals, formed in a Fenton reaction, may be important intermediates in the Type II native chemiluminescence. 相似文献
983.
James J. Steinberg Soichiro Tsukamoto Clemente B. Sledge 《Biochimica et Biophysica Acta (BBA)/General Subjects》1983,757(1):47-58
Proteoglycan breakdown was studied in a coculture model which mimics the confrontation between synovium and cartilage that occurs in rheumatoid arthritis. Bovine nasal-septum cartilage discs radioactively labeled (35SO42? with or without [3H]glucosamine) and ‘chased’ in non-radioactive medium were cultured in contact with minced rheumatoid synovial membranes for intervals up to 8 days. Synovium-stimulated (2–3 fold) cartilage breakdown was unaffected by ascorbate supplementation. Labeled products (small molecules plus proteoglycan complexes) in culture media were characterized by chromatographic, sedimentation and enzymic digestion methods. Breakdown was dominated by the release of a range of proteoglycan products, fully disaggregated and incapable of reaggregation with added hyaluronate. Because constituent glycosaminoglycans were of uniform size, proteoglycan polydispersity was attributed to differences in core protein length. Hydrocortisone inhibited degradation and partially prevented the shift of proteoglycans to lower average molecular weight. An additional breakdown pattern occasionally noted during the initial 48 h of coculture was characterized by release of a subpopulation of low charge-density proteoglycan bearing shortened glycosaminoglycan chains, consistent with glycosidase action. We conclude that rheumatoid synovia exhibit two distinct cartilage degradative potencies in vitro that may be important in vivo: (a) A variable hyaluronidase-like activity at early culture times, and (b) a dominant proteolytic activity generating an array of disaggregated proteoglycann products that differ largely on the basis of their core lengths. The response to hydrocortisone is consistent with inhibition of proteolysis through the stabilization of cellular membranes. 相似文献
984.
985.
986.
987.
988.
In three patients with juvenile rheumatoid arthritis, serum IgA concentrations were within the normal limit at the onset of disease and before aspirin administration. After aspirin administration, their serum IgA levels gradually decreased. After discontinuation of aspirin, their serum IgA levels gradually increased. These results suggest that IgA deficiency may be due to aspirin administration in such patients. The IgA production in vitro of peripheral blood mononuclear cells from a patient taken 3 months of discontinuation of aspirin was markedly inhibited by preincubation with aspirin. Since the patients' serum IgG and IgM levels hardly changed the heavy chain class switching may be influenced by aspirin through some undefined mechanisms.Abbreviations CH
heavy chain constant region
-
3H-TdR
3H-thymidine
- Hepes
N-2-hydroxyethyl-piperazine-N-2-ethanesulfonic acid
- JRA
juvenile rheumatoid arthritis
- MEM
minimum essential medium
- PBMCs
peripheral blood mononuclear cells
- PBS
phosphate buffered saline
- PFCs
plaque forming cells
- PWM
pokeweed mitogen
- SI
stimulation index 相似文献
989.
990.
Bruce M. Rothschild 《Journal of medical primatology》1993,22(5):313-316
Sixty skeletons of Callithrix jacchus were examined to identify spondyloarthropathy. Erosive disease in Callithrix was confirmed as spondyloarthropathy on the basis of diagnostic sacroiliac erosions, syndesmophyte formation, and the nature and distribution of the peripheral joint erosions. 相似文献