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31.
Korstjens IJ Rouws CH van der Laarse WJ Van der Zee L Stienen GJ 《Journal of muscle research and cell motility》2002,23(1):93-102
In this study alterations are characterized which occur, in myocardial force development morphological appearance and protein composition, during the development of cardiac hypertrophy and heart failure in monocrotaline (MCT) treated rats. The transition from cardiac hypertrophy to heart failure was studied by comparing the results from control (CON) and two MCT groups (40 and 44 mg/kg body weight). The three experimental groups consisted of at least five animals each. Parameters studied were: body weight (measured daily), lung/body weight ratio, right ventricular wall volume and thickness, and force development in thin right ventricular trabeculae at 27°C, using different extracellular calcium concentrations and pacing frequencies. MCT injection resulted in marked right ventricular hypertrophy and heart failure as evidenced by an up to 2-fold increase in lung/body weight ratio and a 1.7-fold increase in wall volume. The MCT groups showed a negative force–frequency relation and maximum force was up to 2-fold less than in the CON group. Protein analysis by means of one- and two-dimensional gel electrophoresis revealed a marked (7-fold) up-regulation of the slow myosin heavy chain isoform as well as a 4.5-fold increase in the content of the cytoskeletal protein desmin, whereas the mitochondrial protein ATP-synthase content was reduced. Hence MCT-induced cardiac hypertrophy and heart failure result in altered cellular calcium handling, depression of maximum force output, an increase in the economy of myocardial contraction and changes in cytoskeletal structure and energy supply. 相似文献
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Cell-mediated immunity to proteoglycan antigens was assessed by leucocyte migration inhibition and by lymphocyte stimulation tests in patients with rheumatoid arthritis or with ankylosing spondylarthritis, in patients with relapsing synovitis after a single trauma to their knee joints, and in healthy donors. Both tests revealed a sensitization in most of the patients examined with various proteoglycan antigens derived from human cartilaginous tissues, rheumatoid synovial fluid, and species-common antigen of bovine nasal cartilage. Anybodies against proteoglycan antigens of human articular cartilage were detected by solid-phase radioimmunoassay in eleven out of twenty-nine sera from patients with rheumatoid arthritis and in four out of six rheumatoid synovial fluids. The results suggest that the cartilage antigenic components released by an inflammatory process or trauma may trigger a vicious circle of chronic inflammation and joint destruction. 相似文献
35.
Adding salmeterol to an inhaled corticosteroid reduces allergen-induced serum IL-5 and peripheral blood eosinophils 总被引:3,自引:0,他引:3
Koopmans JG Lutter R Jansen HM van der Zee JS 《The Journal of allergy and clinical immunology》2005,116(5):1007-1013
BACKGROUND: Adding a long-acting beta(2)-agonist to inhaled corticosteroids results in better symptomatic asthma control than increasing the dose of inhaled corticosteroids. OBJECTIVE: Investigating whether adding the long-acting beta(2)-agonist salmeterol to the inhaled corticosteroid fluticasone propionate has an effect on allergen-induced allergic inflammation in asthma. METHODS: Bronchial allergen challenges were performed in 26 patients with allergic asthma, pretreating them with a single dose of either fluticasone/salmeterol (100/50 microg) or fluticasone alone (100 microg), in a double-blind, randomized, cross-over design. Sputum and serum markers of bronchial inflammation were measured after allergen challenge, as well as lung function parameters. Primary outcomes were sputum eosinophil numbers and eosinophil cationic protein. RESULTS: Asthmatic responses after allergen challenge were significantly reduced after pretreatment with fluticasone/salmeterol relative to fluticasone alone. Sputum inflammatory markers after allergen challenge were not significantly affected by fluticasone/salmeterol pretreatment. By contrast, serum IL-5 was significantly reduced (geometric mean serum IL-5 [SEM]: 0.5 [0.3] vs 1.1 [0.3] pg/mL 1 hour and 0.6 [0.3] vs 1.1 [0.3] pg/mL 6 hours after challenge with fluticasone/salmeterol vs fluticasone alone pretreatment, respectively; P values < .05). Also, peripheral blood eosinophils were significantly reduced (geometric mean number x 10(6)/L [SEM]: 172 [0.1] vs 237 [0.1] at 6 hours and 271 [0.1] vs 351 [0.1] at 24 hours with fluticasone/salmeterol vs fluticasone alone pretreatment, respectively; P < .05). CONCLUSION: Adding salmeterol to fluticasone reduces allergen-induced serum IL-5 and peripheral blood eosinophils. This phenomenon may contribute to the improved clinical outcomes that result from adding a long-acting beta(2)-agonist to inhaled corticosteroids. 相似文献
36.
G. SZÜCS M. KÁVAI P. SURÁNYI E. KISS I. CSIPÖ G. SZEGEDI 《Scandinavian journal of immunology》1994,40(5):481-484
The expression of FcγRI, FcγRII, and FcγRIII (the IgG receptors CD64, CD32, CD16) as well as CR3 (the C3bi receptor, CD11b) on monocytes in the blood of patients with systemic lupus erythematosus (SLE) was investigated. The relationship between the receptor expression and the serum immune complex (IC) concentration was analysed. The decrease in mean fluorescence intensity (FI) of the FcγRII of patients' monocytes stained by specific monoclonal antibodies (MoAb IV3) was very close to statistical significance ( P = 0.052). The expression (FI) of CR3 (using MoAb OKM1) on monocytes of patients was also decreased, but not significantly. The detected decrease of FcγRII and CR3 was inversely correlated with the high circulating immune complex level in patients' sera. At the same time, FcγRI expression on SLE monocytes (using MoAb 32) was significantly elevated and this change was in parallel with the serum IC concentration. 相似文献
37.
Lehner T Bergmeier LA Wang Y Tao L Sing M Spallek R van der Zee R 《European journal of immunology》2000,30(2):594-603
Heat shock proteins (HSP) are widely distributed and highly immunogenic molecules. A novel property reported here is that stimulation with HSP70 of CD8-enriched T cells derived from naive non-human primates caused a dose-dependent increase in concentrations of the beta-chemokines RANTES, macrophage inflammatory protein (MIP)-1alpha or MIP-1beta. However, the concentrations of these beta-chemokines were greatly increased when the CD8 T cells derived from HSP70-immunized non-human primates were stimulated with HSP70. HSP linked to peptides or proteins combined generation of beta-chemokines with an adjuvant function by enhancing specific T cell proliferative responses and IgG and IgA antibodies. The beta-chemokine and adjuvant functions were also elicited by topical mucosal administration of HSP linked to an antigen. We postulate that microbial HSP can stimulate beta-chemokine production which may be responsible for innate adjuvanticity, as was found in cells eluted from normal rectal mucosal tissue, and constitutes a significant component of the mucosal-associated lymphoid system. Furthermore, stimulation of innate immunity may drive adaptive immunity and account for the protective effects of HSP against tumors and viruses. 相似文献
38.
Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献
39.
Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation. 相似文献
40.
Bioassay-guided fractionation of the aerial parts ofPilea mongolica (Urticaceae) afforded two cytotoxic triterpenoids, epi-oleanolic acid (I) and oxo-oleanolic acid (II). The structures of the compounds were confirmed by spectral and synthetic evidences. CompoundI and compoundII exhibited cytotoxicity against cultured human tumor cell lines, A549 (non small cell lung adenocarcinoma), SK-OV-3 (ovarian), SK-MEL-2 (skin melanoma), XF498 (CNS) and HCT15 (colon) with ED(50) values of 3.2 approximately 8.1 mug/ml and 0.7 approximately 6.8 mug/ml, respectively. 相似文献