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51.
Leo AB Joosten Erik Lubberts Monique MA Helsen Tore Saxne Christina JJ Coenen-de Roo Dick Heinegård Wim B van den Berg 《Arthritis research & therapy》1999,1(1):81-11
Destruction of cartilage and bone are hallmarks of human rheumatoid arthritis (RA), and controlling these erosive processes
is the most challenging objective in the treatment of RA. Systemic interleukin-4 treatment of established murine collagen-induced
arthritis suppressed disease activity and protected against cartilage and bone destruction. Reduced cartilage pathology was
confirmed by both decreased serum cartilage oligomeric matrix protein (COMP) and histological examination. In addition, radiological
analysis revealed that bone destruction was also partially prevented. Improved suppression of joint swelling was achieved
when interleukin-4 treatment was combined with low-dose prednisolone treatment. Interestingly, synergistic reduction of both
serum COMP and inflammatory parameters was noted when low-dose interleukin-4 was combined with prednisolone. Systemic treatment
with interleukin-4 appeared to be a protective therapy for cartilage and bone in arthritis, and in combination with prednisolone
at low dosages may offer an alternative therapy in RA. 相似文献
52.
53.
Fast folding of a prototypic polypeptide: the immunoglobulin binding domain of streptococcal protein G. 总被引:5,自引:6,他引:5 下载免费PDF全文
J. Kuszewski G. M. Clore A. M. Gronenborn 《Protein science : a publication of the Protein Society》1994,3(11):1945-1952
The folding of the small (56 residues) highly stable B1 immunoglobulin binding domain (GB1) of streptococcal protein G has been investigated by quenched-flow deuterium-hydrogen exchange. This system represents a paradigm for the study of protein folding because it exhibits no complicating features superimposed upon the intrinsic properties of the polypeptide chain. Collapse to a semicompact state exhibiting partial order, reflected in protection factors for ND-NH exchange up to 10-fold higher than that expected for a random coil, occurs within the dead time (< or = 1 ms) of the quenched flow apparatus. This is followed by the formation of the fully native state, as monitored by the fractional proton occupancy of 26 backbone amide groups spread throughout the protein, in a single rapid concerted step with a half-life of 5.2 ms at 5 degrees C. 相似文献
54.
55.
Subcellular localization of DNA-binding protein BA by immunofluorescence and immunoelectron microscopy 总被引:1,自引:2,他引:1 下载免费PDF全文
Nonhistone protein BA has been shown to decrease in amount in the chromatin of growth- stimulated normal rat liver (Yeoman et al. 1975. Cancer Res. 35:1249-1255) and in mitogen-stimulated normal human lymphocytes (Yeoman et al. 1976. Exp. Cell Res. 100:47- 55.). Subsequently, protein BA was purified and was shown to prefer to bind to double- stranded A-T-rich DNAs (Catino et al. 1978. Biochemistry. 17:983-987.). Immunization of rabbits with highly purified protein BA has resulted in the production of a specific antibody. A specific immunoreactivity for chromosomal protein BA has been demonstrated by immunoelectrophoresis and double antibody immunoprecipitation analysis with rabbit anti-BA immunoglobulin and IgG fractions. Light microscope examination of normal rat liver crysections by the indirect immunofluorescence procedure has demonstrated a cytoplasmic as well as a nuclear localization for protein BA with a pronounced perinucleolar fluorescence. Immunoelectron microscopy employing the peroxidase antiperoxidase method of antigen localization has confirmed the immunofluorescence data and has show a heterochromatin localization for protein BA. The relationship of the localization of protein BA to gene control in quiescent cells or to configurations of heterochromatin as well as the marked reduction in the amounts of protein BA which occur in stimulated growth states remains to be defined. 相似文献
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58.
JJ Malemba JM Mbuyi-Muamba J Mukaya X Bossuyt MP Emonds K Deiteren R Westhovens P Verschueren 《Arthritis research & therapy》2013,15(4):R89
Introduction
Little is known about rheumatoid arthritis in the black, particularly in Congolese, populations. Our objective was to describe the phenotype and genotype of rheumatoid arthritis (RA) in Congolese.Methods
All consecutive rheumatoid arthritis (RA) patients attending Kinshasa University Hospital in a three-year time period were included. Demographics, clinical features and tobacco consumption were noted. Disease Activity Score (DAS)-28 based on the erythrocyte sedimentation rate (ESR), Health Assessment Questionnaire (HAQ), anti-citrullinated peptide antibodies (CCP) antibodies and rheumatoid factor (RF) were determined. Radiographs were scored according to Sharp-van der Heijde. On a subset of patients and controls HLA-DRB1 typing was performed.Results
A total of 114 females and 14 males aged 51.2 ± 14.9 were included. Mean duration of symptoms was four years. Moderate tobacco consumption was reported in a minority of patients. DAS-28 at first visit was >5.1 and HAQ ≥0.5 in all patients. X-rays showed joint erosions and/or joint space narrowing, mostly of a moderate grade in 55.8% of patients. Anti-CCP and/or RF were present in 48.6% of patients with available data (n = 72) and in 3.0% of controls (n = 67). Radiographic changes and nodules were more frequent in RF or anti-CCP positive patients. One copy of the shared epitope was found in 13 patients (35.1%) and 3 controls (12.5%). Two copies were found in one patient (2.7%) and in one control (4.2%).Conclusion
Congolese patients with RA consult long after disease onset. Despite this delay, the majority presents without major damage and is RF, anti-CCP and SE negative. We put forward the hypothesis that besides different environmental factors there is probably also a particular genetic risk profile in Congolese patients, different from the HLA-DRB1 shared epitope. 相似文献59.
Using cultured cells from bovine and rat aortas, we have examined the possibility that endothelial cells might regulate the growth of vascular smooth muscle cells. Conditioned medium from confluent bovine aortic endothelial cells inhibited the proliferation of growth-arrested smooth muscle cells. Conditioned medium from exponential endothelial cells, and from exponential or confluent smooth muscle cells and fibroblasts, did not inhibit smooth muscle cell growth. Conditioned medium from confluent endothelial cells did not inhibit the growth of endothelial cells or fibroblasts. In addition to the apparent specificity of both the producer and target cell, the inhibitory activity was heat stable and not affected by proteases. It was sensitive flavobacterium heparinase but not to hyaluronidase or chondroitin sulfate ABC lyase. It thus appears to be a heparinlike substance. Two other lines of evidence support this conclusion. First, a crude isolate of glycosaminoglycans (TCA-soluble, ethanol-precipitable material) from endothelial cell-conditioned medium reconstituted in 20 percent serum inhibited smooth muscle cell growth; glycosaminoglycans isolated from unconditioned medium (i.e., 0.4 percent serum) had no effect on smooth muscle cell growth. No inhibition was seen if the glycosaminoglycan preparation was treated with heparinase. Second, exogenous heparin, heparin sulfate, chondroitin sulfate B (dermatan sulfate), chondroitin sulfate ABC, and hyaluronic acid were added to 20 percent serum and tested for their ability to inhibit smooth muscle cell growth. Heparin inhibited growth at concentrations as low as 10 ng/ml. Other glycosaminoglycans had no effect at doses up to 10 μg/ml. Anticoagulant and non- anticoagulant heparin were equally effective at inhibiting smooth muscle cell growth, as they were in vivo following endothelial injury (Clowes and Karnovsk. Nature (Lond.). 265:625-626, 1977; Guyton et al. Circ. Res. 46:625-634, 1980), and in vitro following exposure of smooth muscle cells to platelet extract (Hoover et al. Circ. Res. 47:578-583, 1980). We suggest that vascular endothelial cells may secrete a heparinlike substance in vivo which may regulate the growth of underlying smooth muscle cells. 相似文献
60.
Glycosylation sites and site-specific glycosylation in human Tamm- Horsfall glycoprotein 总被引:3,自引:1,他引:3
The N-glycosylation sites of human Tamm-Horsfall glycoprotein from one
healthy male donor have been characterized, based on an approach using
endoproteinase Glu-C (V-8 protease, Staphylococcus aureus ) digestion and a
combination of chromatographic techniques, automated Edman sequencing, and
fast atom bombardment mass spectrometry. Seven out of the eight potential
N-glycosylation sites, namely, Asn52, Asn56, Asn208, Asn251, Asn298,
Asn372, and Asn489, turned out to be glycosylated, and the potential
glycosylation site at Asn14, being close to the N-terminus, is not used.
The carbohydrate microheterogeneity on three of the glycosylation sites was
studied in more detail by high-pH anion-exchange chromatographic profiling
and 500 MHz1H-NMR spectroscopy. Glycosylation site Asn489 contains mainly
di- and tri-charged oligosaccharides which comprise, among others, the
GalNAc4 S (beta1-4)GlcNAc terminal sequence. Only glycosylation site Asn251
bears oligomannose-type carbohydrate chains ranging from Man5GlcNAc2to
Man8GlcNAc2, in addition to a small amount of complex- type structures.
Profiling of the carbohydrate moieties of Asn208 indicates a large
heterogeneity, similar to that established for native human Tamm-Horsfall
glycoprotein, namely, multiply charged complex-type carbohydrate
structures, terminated by sulfate groups, sialic acid residues, and/or the
Sda-determinant.
相似文献