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Many bilateral distal extension removable partial dentures possess insufficient guidance to control their dislodgement. When such a situation is observed, the tips of retentive clasps must be located in both an occlusogingival and mesiodistal (away from the denture base area) undercut. The specific location can be identified with a dental surveyor that has been adapted to function in two planes. Details of the adaptation process and use of the surveyor are described.  相似文献   

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BACKGROUND AND AIMS OF THE STUDY: Valve repair, where suitable, is the preferred option in patients who require mitral surgery. A number of studies have shown excellent long-term results, but most were undertaken in tertiary referral centers with a high throughput of patients. METHODS: We present our experience in 60 patients, aged 60 +/- 14 years, undergoing repair between 1984 and 1993. Most patients (83%) were in New York Heart Association (NYHA) class II or III at the time of surgery; 27% had concomitant ischemic heart disease. Almost all (98%) had posterior leaflet repair and 18% had anterior leaflet repair. Eight surgeons each performed a mean of 7.5 operations during this period. RESULTS: The 30-day mortality rate was 3.3%. There were seven late deaths. Five patients underwent reoperation for mitral regurgitation (two early, three late). At six years, 60% of patients were alive, or free of stroke or reoperation. Late follow up was obtained in 45 of 47 surviving patients: 95% were in NYHA class I or II; one-third were on anticoagulants for atrial fibrillation; 90% had mild (or less) mitral regurgitation on echocardiography. CONCLUSIONS: These data show that most patients have a very good outcome from valve repair surgery and encourage the trend towards operating earlier in the course of the disease. Adverse outcomes occurred mainly in patients who were highly symptomatic at the time of surgery. The high proportion of patients on postoperative anticoagulants underscores the importance of operating before atrial fibrillation becomes permanent.  相似文献   

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OBJECTIVE: To evaluate the effect of early 'aggressive' drug treatment on radiographic progression in patients with recent-onset rheumatoid arthritis (RA), compared to conventional stepwise increasing intensity of treatment. DESIGN: Prospective follow-up study with an experimental group and a historical control group both divided into a high-risk subgroup and a low-risk subgroup, based on prognostic factors. The effect of the 'aggressive' and the conventional treatment strategy was compared between both high-risk groups; the low-risk groups, both treated according to the conventional treatment strategy, were used to ensure internal consistency between the experimental and the historical groups. PATIENTS: A total of 228 consecutive patients with recent-onset RA (complaints < 1 yr at study entry). METHODS: The 'aggressive' drug treatment consisted of institution of relatively fast-acting disease-modifying anti-rheumatic drugs (DMARDs) (sulphasalazine, methotrexate) immediately after diagnosis, and rapid adjustment of dosage and/or drug in the case of insufficient response as measured by a change in C-reactive protein (CRP) level. Radiographic damage was assessed according to a modified version of Sharp's method and cumulative disease activity expressed as CRP-area under the curve (CRP-AUC). The occurrence of side-effects was also evaluated. RESULTS: After 2 yr of follow-up, comparison of the two high-risk subgroups showed the radiographic progression in the 'aggressively' treated subgroup to be significantly lower than that in the control group [Sharp score: median (range) 26 (0-100) vs 35 (1-188); P = 0.03]. Cumulative CRP values were also significantly lower than in the control high-risk subgroup [CRP-AUC: median (range) 1963 (212-8515) vs 3025 (46-15 632) mg.week/1; P = 0.002). This was achieved without an increase in the occurrence of side-effects. There was no difference between the two low-risk subgroups with regard to entry characteristics, CRP-AUC values or radiological progression, indicating comparability between the two groups. CONCLUSION: Early 'aggressive' drug treatment, using sulphasalazine and/or methotrexate, aimed at reduction of the CRP level, significantly reduces the (rate of) radiographic progression in RA.  相似文献   

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OBJECTIVE: Some chemokine receptors have been shown to be co-receptors for human immunodeficiency virus (HIV-1). A 32 base pair deletion allele in the CC chemokine receptor 5 gene (CCR5 delta32 allele) affects both transmission of HIV-1 and acquired immunodeficiency syndrome (AIDS)-free survival. Chemokines are suggested to be critical for establishment of inflammatory processes in autoimmune diseases such as rheumatoid arthritis (RA). We hypothesized that the defective allele may modulate the inflammatory process in RA. METHODS: Using polymerase chain reaction methods, we investigated the significance of the CCR5 delta32 allele in 163 Danish patients with RA and monitored clinical and paraclinical variables. RESULTS: The gene frequency of the CCR5 delta32 allele (0.10) did not deviate significantly from healthy controls and from that reported in healthy Caucasian populations, nor did the distribution deviate from the Hardy-Weinberg predictions (131 wild type, 30 heterozygous, 2 homozygous for the deletion allele; p = 0.85). However, a significantly increased proportion of those carrying the deletion allele were negative for IgM rheumatoid factor (RF) compared to those homozygous for the normal allele (29 vs 9%; p = 0.007). The proportion of CCR5 delta32 allele carriers with swollen joints was decreased compared to those homozygous for the normal allele (35 vs 58%, respectively; p = 0.03), as was the duration of morning stiffness (median 0 vs 60 min, respectively; p = 0.0002). CONCLUSION: The CCR5 delta32 allele seems to have some influence on RA variables including RF, which suggests that inhibition of chemokine receptors might be a potential target for disease modifying therapy in RA.  相似文献   

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The effect of an allelic polymorphism in the BV1S1 gene segment on recognition of major histocompatibility complex (MHC)-peptide complexes by a specific T cell receptor (TCR) was studied using RBL 2H3 cells transfected with TCR-CD3 zeta chimeric receptors. An HLA-A2-restricted human immunodeficiency virus (HIV) pol-specific cytotoxic T lymphocyte (CTL) clone utilizing the BV1S1A2 gene in combination with AV2S1A2 was identified and the extracellular domains of the TCR were fused to CD3 zeta. In degranulation assays RBL 2H3 transfectants expressing this receptor maintained the specificity of the parental CTL clone. The allelic variant BV1S1A1N1 containing a glutamine for histidine substitution at position 48 in the loop of the second complementarity-determining region was generated by site-directed mutagenesis. Transfection of this molecule as a CD3 zeta chimera together with the original AV2S1A2 CD3 zeta molecule resulted in cell surface expression of both chains but a loss of recognition of HLA-A2 HIV pol peptide-pulsed targets. The effect of this polymorphism on MHC-peptide recognition supports current models of TCR MHC-peptide interaction and provides evidence for a functional role for polymorphism in the TCRV genes.  相似文献   

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OBJECTIVE: To identify features of the T cell receptors (TCRs) present on clonally expanded T cells in the joints of patients with similar types of childhood rheumatic disease. Vbeta8 and Vbeta20 TCRs were selected as prototypic for polyarticular juvenile rheumatoid arthritis (JRA) and pauciarticular/juvenile spondylarthropathy (SpA), respectively. METHODS: The portion of the TCR beta chain involved in antigen recognition in the synovial tissue, synovial fluid, and peripheral blood from patients with JRA and juvenile SpA was cloned and sequenced. The frequency of expanded clonotypes, size of expansions, the Jbeta region, and sequence motifs were determined for >2,000 sequences. RESULTS: The majority of Vbeta20 and Vbeta8 clonal expansions were found in the joint rather than the peripheral blood. While instances of both Vbeta8 and Vbeta20 clonal expansion were detected in all disease types, the features of these expanded clonotypes were specific for disease type and Vbeta family. For example, Vbeta20 clonal expansion was characterized by many small expanded clonotypes in samples from patients with pauciarticular JRA and juvenile SpA while single large Vbeta8-specific expansions were found only in patients with polyarticular disease. Motifs specific to individual patients were identified, and for Vbeta20 clonotypes, a motif was found in synovial tissue samples. CONCLUSION: Identification of common TCR features in oligoclonal expansions within individual patients and between patients with the same type of JRA suggests the recognition of a common or limited group of antigens in these diseases.  相似文献   

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During T cell development the T cell receptor (TCR) beta chain is expressed before the TCR alpha chain. Experiments in TCR beta transgenic severe combined immune deficiency (SCID) mice have shown that the TCR beta protein can be expressed on the cell surface of immature thymocytes in the absence of the TCR alpha chain and that the TCR beta protein controls T cell development with regard to cell number, CD4/CD8 expression and allelic exclusion of the TCR beta chain. Subsequent experiments have shown that on the surface of thymocytes from TCR beta transgenic SCID mice the TCR beta protein can be expressed in a monomeric and dimeric form whereas only the dimeric form was found on the surface of a TCR beta-transfected, immature T cell line. The results presented here show that normal thymocytes from 16-day-old fetuses likewise express only the dimeric form and that the monomeric form on the surface of thymocytes from transgenic mice results from glycosyl phosphatidylinositol linkage. Our results show for the first time that under physiological conditions a TCR beta dimer can be expressed on the cell surface without the TCR alpha chain.  相似文献   

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The generation of a productive "in-frame" T cell receptor beta (TCR beta), immunoglobulin (Ig) heavy (H) or Ig light (L) chain variable region gene can result in the cessation of rearrangement of the alternate allele, a process referred to as allelic exclusion. This process ensures that most alphabeta T cells express a single TCR beta chain and most B cells express single IgH and IgL chains. Assembly of TCR alpha and TCR gamma chain variable region genes exhibit allelic inclusion and alphabeta and gammadelta T cells can express two TCR alpha or TCR gamma chains, respectively. However, it was not known whether assembly of TCR delta variable regions genes is regulated in the context of allelic exclusion. To address this issue, we have analyzed TCR delta rearrangements in a panel of mouse splenic gammadelta T cell hybridomas. We find that, similar to TCR alpha and gamma variable region genes, assembly of TCR delta variable region genes exhibits properties of allelic inclusion. These findings are discussed in the context of gammadelta T cell development and regulation of rearrangement of TCR delta genes.  相似文献   

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OBJECTIVE: To describe the longitudinal radiographic course of rheumatoid arthritis (RA), and to identify and quantitate predictors of radiographic progression. METHODS: This prospective, longitudinal study of radiographic progression and clinical predictors of RA involved 256 patients with RA who were seen within the first 2 years of disease (mean 0.77 years) and were followed up for up to 19 years. Participants underwent a total of 6,278 clinical assessments (mean 24.5) and 934 paired radiographs (mean 3.1, range 2-6). Clinical assessments at every visit included determination of the erythrocyte sedimentation rate (ESR), grip strength, pain scores, tender joint counts, and anxiety and depression measurements. Regression analyses utilized time-integrated predictors. RESULTS: Overall, radiographic progression rates, as measured by the summary Sharp scores, appeared constant over the course of RA. The strongest correlate of progression was the time-integrated ESR (rho=0.53). This association grew stronger with time. At 0-5 years, 5-10 years, 10-15 years, and 15-20 years, correlations were 0.40, 0.50, 0.65, and 0.74, respectively, and for the period 10-20 years, the correlation was 0.67. In multivariate models, the mean ESR, mean grip strength, rheumatoid factor positivity, and tender joint count were independent predictors of radiographic progression. CONCLUSION: Radiographic damage occurs at a constant rate in RA, and is not greater early in RA or reduced later in the course of the illness. Acute-phase reactants are, by far, the strongest determinants of progression.  相似文献   

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OBJECTIVE: To evaluate radiologic progression in patients with early rheumatoid arthritis (RA) receiving methotrexate (MTX) as the first slow acting drug. METHODS: An open, prospective study of 29 patients with RA (21 F, 8 M, mean age 48.5+/-15.4 yrs). The mean duration of RA was 6.6 (2-60) months; and rheumatoid factor was present in 11 cases. Clinical, biological, and radiographic evaluations were done before the start of MTX treatment and after 13+/-3.8 months. Radiographs of hands and wrists were blindly studied by 2 physicians, using Larsen's and modified Sharp's methods. There was a significant correlation for the scores of the 2 physicians evaluated by kappa coefficient. Radiographic evolution was defined as an increase of 15 points in the radiologic score by each method used. RESULTS: Patients showed significant clinical improvement after one year of MTX treatment. Despite clinical and biological improvement, significant mean radiographic progression was noted, with Larsen's method (p = 0.001) and Sharp's method (p = 0.034), without reaching the maximum score. However, using the definition of radiographic progression, the radiologic scores indicated stabilization in 23 patients with Larsen's method and in 24 patients with Sharp's method. CONCLUSION: This study revealed mild radiographic progression in early RA patients treated with MTX for one year. Further controlled studies are needed.  相似文献   

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Previous studies have shown that injection of galanin (GAL: 6.2 nmol/kg) causes prolonged inhibition of cardiac vagal action in anaesthetised cats. Stimulation of the cardiac sympathetic nerve (16 Hz for 5 min) also produces inhibition of cardiac vagal action, an effect which has been proposed to be due to the release of endogenous GAL from sympathetic nerves. In a previous study we tested galantide (M15) and in this study we compared galantide with two other GAL antagonists for their GAL antagonist activity in our experimental model. Each of these incorporate the N-terminal fragment GAL 1-13 and a C-terminal portion of another bioactive peptide and all are C-terminally amidated. GAL 1-13 Substance P 5-11 amide (galantide: M15: 62 nmol/kg and 156 nmol/kg), GAL 1-13 Spantide amide (C7: 156 nmol/kg) and GAL 1-13 NPY 24-36 amide (M32a: 62 nmol/kg) all significantly reduced the cardiac vagal inhibitory effect of exogenous GAL and also reduced the effect of sympathetic stimulation on subsequent cardiac vagal slowing, giving strong support to our hypothesis that GAL is involved in this phenomenon. No antagonist reduced the depressor effect of GAL. This study demonstrates the GAL antagonist properties of these agents on autonomic neuroeffector functions making them useful tools in elucidating further functions of endogenous GAL.  相似文献   

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Two aspects of T cell differentiation in T cell receptor (TCR)-transgenic mice, the generation of an unusual population of CD4-CD8-TCR+ thymocytes and the absence of gamma delta cells, have been the focus of extensive investigation. To examine the basis for these phenomena, we investigated the effects of separate expression of a transgenic TCR alpha chain and a transgenic TCR beta chain on thymocyte differentiation. Our data indicate that expression of a transgenic TCR alpha chain causes thymocytes to differentiate into a CD4-CD8-TCR+ lineage at an early developmental stage, depleting the number of thymocytes that differentiate into the alpha beta lineage. Surprisingly, expression of the TCR alpha chain transgene is also associated with the development of T cell lymphosarcoma. In contrast, expression of the transgenic TCR beta chain causes immature T cells to accelerate differentiation into the alpha beta lineage and thus inhibits the generation of gamma delta cells. Our observations provide a model for understanding T cell differentiation in TCR-transgenic mice.  相似文献   

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We sought to detect anti-Fc gamma receptor (Fc gamma R) autoantibodies and soluble Fc gamma R in the serum and synovial fluid (SF) from patients with rheumatoid arthritis (RA) and to correlate these serological abnormalities to the polymorphonuclear cell (PMN) activation state. Paired samples of blood and SF were obtained from 33 RA patients as well as blood from 25 normal adults from SF from 20 non-RA patients. Anti-Fc gamma R autoantibodies were assessed by an enzyme-linked immunosorbent assay (ELISA) using recombinant human Fc gamma R as the substrate. Soluble Fc gamma RIII was determined by an ELISA based on the combination of two monoclonal antibodies (MAb). The mean fluorescence intensity (MFI) of complement receptor 1 (CD35) and 3 (CD11b) and Fc gamma RIII (CD16) was evaluated by flow cytometry on the membrane of PMN. IgM anti-Fc gamma RIII activity was present in seven RA sera and five SF, and IgG in eight RA sera and six SF. The average concentration of soluble Fc gamma RIII was 1.80 +/- 3.50 micrograms/ml in RA patients and 0.33 +/- 0.06 micrograms/ml in normal adults (P < 0.05). This was elevated in the SF of 15 RA, while normal in that of all the non-RA patients. There was an inverse correlation between the CD16 MFI on the PMN and the serum/SF soluble Fc gamma RIII level, whereas the density of CD35 and CD11b was markedly augmented. Anti-Fc gamma RIII activity exists in RA patients, associated with soluble Fc gamma RIII. PMN activation could be due to these autoantibodies and thereby obviate the clearance of immune complexes.  相似文献   

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The repertoire of T cell receptor (TCR) V beta chain utilization was investigated in PL/J, CXJ-1, SJL/J and B10.S-->SJL/J chimeric mice in response to either myelin basic protein (MBP) or the strain-specific encephalitogenic peptide. Our analysis showed that there was an overlapping predominance in the TCR V beta gene utilization in the MBP-specific responses, which were independent of the major histocompatibility complex (MHC) class II haplotype present, and the immunodominant peptide region recognized in these different strains. In those mice having the TCR V beta b haplotype (PL/J, CXJ-1, and the B10.S-->SJL chimera) either the TCR V beta 4, 8, and 13 or the TCR V beta 4, 6, and 13 predominated. In contrast, in mice with TCR V beta a haplotype (SJL/J) V beta 4, 6, and 17a were found. However, the quantitative distribution of these preferentially utilized TCR V beta chains in each strain was defined by the MHC class II haplotype and the immunodominant peptide recognized. The expression of the V beta 8 gene product in the peripheral TCR repertoire did not always correlate with predominant V beta 8 utilization in the MBP-specific response.  相似文献   

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