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ID PMID Title PublicationDate abstract
19705121 Etanercept treatment in rheumatoid arthritis patients with chronic kidney failure on predi 2010 Sep Rheumatoid arthritis (RA) patients with chronic kidney failure are intolerant to most disease-modifying antirheumatic drugs (DMARDs) and NSAIDs due to their potential toxicities. Although the tumor necrosis factor (TNF) inhibitors have emerged as a highly effective treatment for RA, their safety and efficacy in RA patients with chronic kidney failure have not been well reported. We retrospectively evaluated the safety and efficacy of etanercept treatment in RA patients with chronic kidney failure. We describe three RA patients with chronic kidney failure who had been treated with DMARDs, steroids and NSAIDs, but were discontinued from these classical agents due to several side effects and nephrotoxicity. The patients were treated with 25 mg of etanercept once or twice a week. We evaluated disease activity and used decreasing renal function and increasing number of infections to monitor safety. All three patients improved after starting etanercept treatment and their steroid requirements were decreased. Linear relationships between Modification of Diet in Renal Disease study equation (MDRD) glomerular filtration rate (GFR) and time were observed. Thus, in all patients, the changes in GFR did not represent superimposed acute drug toxicity, but rather chronic progressive renal failure. These cases show that etanercept may be a safe and effective treatment option for RA patients with chronic kidney failure.
20574650 Elevated level of serum cystatin-C concentration is a useful predictor for myelosuppressio 2010 Dec Methotrexate (MTX) is indispensable for the treatment of rheumatoid arthritis (RA). However, a small number of patients treated with MTX occasionally encounter some life-threatening events, including myelosuppression. Renal insufficiency, one of risk factors for these events, is difficult to assess because the serum creatinine concentration level and estimated glomerular filtration rate are sometimes inaccurately determined in aged RA patients. As a better indicator to evaluate this pathology, we measured the serum cystatin-C (Cys-C) level in 78 RA patients ≥ 50 years who were treated with MTX and observed for a year. The measurement achieved successful screening of two patients with leukocytopenia, one with interstitial lung disease (ILD), and two with liver dysfunction. An additional four referral inpatients with MTX-induced adverse events (three with pancytopenia, one with ILD) were enrolled for analysis, amounting to 82 patients. The logistic regression analysis showed that a correlation was observed between myelotoxicity and serum Cys-C level (elevation per 0.1 mg/dl; odds ratio 2.34, 95% confidence interval 1.08-5.09, p = 0.03). In conclusion, elderly RA patients potentially have subclinical renal insufficiency detected by the serum Cys-C concentration level. The elevated level of serum Cys-C is a more sensitive indicator to predict MTX-induced myelotoxicity than that of serum creatinine.
18722089 Valued life activity disability played a significant role in self-rated health among adult 2009 Feb OBJECTIVE: Because self-rated health (SRH) is strongly associated with health outcomes, it is important to identify factors that individuals take into account when they assess their health. We examined the role of valued life activities (VLAs), the wide range of activities deemed to be important to individuals, in SRH assessments. STUDY DESIGN AND SETTING: Data were from three cohort studies of individuals with different chronic conditions--rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and chronic obstructive pulmonary disease (COPD). Each cohort's data were collected through structured telephone interviews. Logistic regression analyses identified factors associated with ratings of fair/poor SRH. All analyses included sociodemographic characteristics, general and disease-specific health-related factors, and general measures of physical functioning. RESULTS: Substantial portions of each group rated their health as fair/poor (RA 37%, SLE 47%, COPD 40%). In each group, VLA disability was strongly associated with fair/poor health (RA: OR=4.44 [1.86,10.62]; SLE: OR=3.60 [2.10,6.16]; COPD: OR=2.76 [1.30,5.85]), even after accounting for covariates. CONCLUSION: VLA disability appears to play a substantial role in individual perceptions of health, over and above other measures of health status, disease symptoms, and general physical functioning.
19969473 Detection of rheumatoid arthritis using non-specific contrast enhanced fluorescence imagin 2010 Mar RATIONALE AND OBJECTIVES: The aim of this study was to develop a new tool for the early detection of inflammatory joint diseases using fluorescence imaging in the near-infrared (NIR) spectral range following the intravenous administration of an unspecific contrast agent. MATERIALS AND METHODS: A laser-supported system for fluorescence imaging of finger joints was designed and constructed. Five patients and a corresponding number of volunteers were examined using 0.1 mg/kg by weight of indocyanine green as an unspecific contrast agent. Fluorescence images were acquired continuously over a period of 15 minutes. As a control, 1 day before optical imaging, all patients and volunteers underwent contrast-enhanced magnetic resonance imaging (MRI) at 0.2 T. On the basis of MRI findings, all examined joints were divided into four groups: no change and mild, moderate, and severe synovitis. The emitted fluorescence photons were quantified in different regions of interest covering the finger joints and finger tips. The normalized fluorescence intensity of contrast agents was compared with MRI findings as a proven standard. RESULTS: NIR dyes of the cyanine class are enriched in inflammatory joints and show a different kinetic behavior compared to normal joints after bolus injection. These findings demonstrate clearly the capability of contrast-enhanced fluorescence imaging to detect early changes caused by rheumatoid arthritis in finger joints. The NIR results were correlated with MRI findings (r = 0.84). CONCLUSION: Contrast-enhanced fluorescence imaging provides adequate information for the evaluation of inflammatory involvement of finger joints comparable to low-field MRI.
19492562 The cementless AGC 2000 knee prosthesis: 20-year results in a consecutive series. 2009 Apr One hundred and fourteen AGC 2000 porous-coated cementless total knee arthroplasties were performed in 102 patients between 1984 and 1986. We report their 20-year results with patient assessment, Hospital for Special Surgery knee score, weight-bearing radiographs done under fluoroscopic control and survivorship analyses. All patients could be accounted for. With prosthesis revision as a failure criterion, the cumulative survival rate of all prosthetic components at 20 years was 84.4%. The fall in success rate was primarily due to early tibial and late patellar component failure. The cumulative survival rate of the tibial component was 97.2% and that of the femoral component was 100% at 20 years.
20644041 Tumor necrosis factor inhibitor-associated dermatomyositis. 2010 Jul BACKGROUND: Dermatomyositis is an autoimmune disease of unknown etiology characterized by inflammation of the skin and muscles. Several medications have been implicated in the development of dermatomyositis; however, the disease has rarely been linked to the use of tumor necrosis factor (TNF) inhibitors. We report 4 cases of dermatomyositis that developed or were exacerbated by exposure to the TNF inhibitors etanercept and adalimumab. Observation Four patients with symptoms of inflammatory arthritis were treated with TNF inhibitors for a duration ranging from 2 months to 2 years. All 4 patients developed symptoms consistent with dermatomyositis, including inflammatory rash and muscle weakness. Their symptoms persisted after discontinuation of the treatment with the TNF inhibitors but responded to treatment with corticosteroids and immunosuppressive medications. CONCLUSIONS: Tumor necrosis factor inhibitors have been associated with the onset of a number of autoimmune disorders, most commonly vasculitis and a lupuslike syndrome. Rarely have they been associated with dermatomyositis. The 4 cases reported herein indicate that TNF inhibitor use can be associated with either induction or exacerbation of dermatomyositis.
19109154 Follistatin-like protein 1 promotes arthritis by up-regulating IFN-gamma. 2009 Jan 1 Follistatin-like protein-1 (FSTL-1) is a poorly characterized protein that is up-regulated in the early stage of collagen-induced arthritis and that exacerbates arthritis when delivered by gene transfer. The current study was designed to determine the mechanism by which FSTL-1 promotes arthritis. FSTL-1 was injected into mouse paws, resulting in severe paw swelling associated with up-regulation of IFN-gamma transcript and the IFN-gamma-induced chemokine, CXCL10. Mice depleted of T cells were protected. A central role for IFN-gamma was confirmed by the finding that mice deficient in IFN-gamma failed to exhibit paw swelling in response to injection of FSTL-1. Furthermore, IFN-gamma secretion from mouse spleen cells exposed to a weak TCR signal was increased 5-fold in the presence of FSTL-1. FSTL-1 could be induced by innate immune signals, including TLR4 agonists and the arthritogenic cytokine, IL-1beta, via an NFkappaB pathway. Finally, FSTL-1 was found to be overexpressed in human arthritis and its neutralization inhibited murine collagen-induced arthritis and suppressed IFN-gamma and CXCL10 production in arthritic joints. These findings demonstrate that FSTL-1 plays a critical role in arthritis by enhancing IFN-gamma signaling pathways and suggest a mechanism by which FSTL-1 bridges innate and adaptive immune responses.
19280940 [Therapeutic apheresis for rheumatic diseases]. 2009 Mar The main stream of treatment for rheumatic disease is pharmacotherapy. Corticosteroids, DMARDs, the immunosuppressive agents and biologics are the gold standard of the treatment. However, some cases showing resistance to these treatments exist, and the potential for side effects exists in all of these pharmacotherapies. Furthermore, there are cases in which pharmacotherapy cannot be effectively used due to organ derangement. Apheresis is totally different from pharmacotherapy as a concept, and it is a treatment to control disease activity by removing the factors which contribute to the pathogenicity. The synchronized therapy of apheresis and pharmacotherapy is the treatment that may result in a more beneficial effect of treatment. This review introduces the experiences as an overall approach to better, safer management for rheumatic diseases.
19416946 The decrease of soluble RAGE levels in rheumatoid arthritis patients following hormone rep 2009 Jul OBJECTIVE: The aim of the study was to prospectively investigate the effects of HRT on serum soluble receptor for advanced glycation end product (sRAGE) levels in RA patients and to determine whether sRAGE production is related to bone/cartilage metabolism. METHODS: Eighty-eight post-menopausal RA patients were randomized to receive vitamin D3 and calcium supplementation with or without HRT (oestradiol plus noretisterone acetate). The levels of total sRAGE in sera were measured before, 1 and 2 years after treatment initiation. Potential associations between sRAGE levels, bone/cartilage metabolic markers and BMD were investigated. RESULTS: Patients receiving HRT displayed significantly decreased levels of serum sRAGE at 1 and 2 years as compared with levels at study entry. The increase in serum oestradiol was associated with the decline in sRAGE levels. Importantly, sRAGE levels at baseline significantly correlated with bone/cartilage turnover markers including C-terminal propeptide of type I procollagen, carboxyterminal telopeptide of type I collagen and cartilage oligomeric matrix protein, and the decrease of sRAGE levels paralleled with diminished concentration of these molecules. BMD in hip and femoral neck and progression of Larsen score at 1 year were associated with baseline sRAGE levels. The decline in sRAGE levels significantly correlated with an increase in total BMD following 2 years of treatment in patients receiving HRT but not in the control group. CONCLUSION: Our findings suggest that HRT decreases the levels of endogenous sRAGE in post-menopausal RA patients implicating its role in sRAGE regulation. In addition, serum sRAGE was associated with BMD and markers of bone/cartilage metabolism. These data suggest that sRAGE is involved directly or indirectly in bone metabolism. Trial registration. Current Controlled Trials, ISRCTN46523456, http://www.controlled-trials.com/isrctn/search.html?srch=ISRCTN46523456.
19095172 Morphologic analysis of the medullary canal in rheumatoid elbows. 2009 Jan Total elbow arthroplasty is a standard approach for patients with arthritic elbows. To design appropriate stems for elbow prostheses, it is important to understand the shape of the medullary canals. The purpose of this study was to evaluate the shape and size of the medullary canals from normal cadavers and rheumatoid arthritis patients. These canals were measured based on geometric constructions of the 3-dimensional bone models generated from computed tomography images. The cross-sectional area of the medullary canals in rheumatoid arthritis patients decreased near the elbow joint as a result of morphologic changes after a long-standing inflammatory reaction. When designing the press-fit component of the humerus, an increase in the width of the transverse diameter of the intramedullary stem could increase stability in the canal. In contrast, for the ulnar component, such morphologic changes would impose difficulty in placing the press-fit model despite an anatomically designed stem. Therefore, a cement technique would be required for improved stabilization of the ulnar component.
19333921 Amphoteric liposomes enable systemic antigen-presenting cell-directed delivery of CD40 ant 2009 Apr OBJECTIVE: Mediation of RNA interference by oligonucleotides constitutes a powerful approach for the silencing of genes involved in the pathogenesis of inflammatory disease, but in vivo application of this technique requires effective delivery to immune cells and/or sites of inflammation. The aim of the present study was to develop a new carrier system to mediate systemic administration of oligonucleotides to rheumatoid arthritis (RA) joints, and to develop an antisense oligonucleotide (ASO)-based approach to interfere with CD40-CD154 interactions in an experimental model of RA. METHODS: A novel liposomal carrier with amphoteric properties, termed Nov038, was developed and assessed for its ability to systemically deliver an ASO directed against CD40 (CD40-ASO). Male DBA/1 mice with collagen-induced arthritis were treated with Nov038-encapsulated CD40-ASO, and the effects of treatment on various parameters of disease activity, including clinical score, paw swelling, lymph node responses, and inflammatory cytokine production in the joints, were assessed. RESULTS: Nov038 was well tolerated, devoid of immune-stimulatory effects, and efficacious in mediating systemic oligonucleotide delivery to sites of inflammation. In mice with collagen-induced arthritis, Nov038 enabled the therapeutic administration of CD40-ASO and improved established disease, while unassisted CD40-ASO was ineffective, and anti-tumor necrosis factor alpha (anti-TNFalpha) treatment was less effective in this model. Nov038/CD40-ASO efficacy was attributed to its tropism for monocyte/macrophages and myeloid dendritic cells (DCs), resulting in rapid down-regulation of CD40, inhibition of DC antigen presentation, and reduction in collagen-specific T cell responses, as well as decreased levels of TNFalpha, interleukin-6 (IL-6), and IL-17 in arthritic joints. CONCLUSION: Amphoteric liposomes represent a novel carrier concept for systemic and antigen-presenting cell-targeted oligonucleotide delivery with clinical applicability and numerous potential applications, including target validation in vivo and inflammatory disease therapeutics. Moreover, Nov038/CD40-ASO constitutes a potent alternative to monoclonal antibody-based approaches for interfering with CD40-CD40L interactions.
19877042 The relationship between synovial lymphocyte aggregates and the clinical response to infli 2009 Nov OBJECTIVE: Some patients with rheumatoid arthritis (RA) exhibit lymphocyte aggregates in the synovium. This study was undertaken to address whether the presence of lymphocyte aggregates before treatment could serve as a biomarker for the clinical response to tumor necrosis factor (TNF) blockade, and to confirm whether the aggregation of synovial lymphocytes is reversible after anti-TNF treatment. METHODS: Synovial tissue biopsy samples were obtained from 97 patients with active RA before the initiation of infliximab treatment. Lymphocyte aggregates in the synovial tissue were counted and also graded for size. Logistic regression analysis was performed to identify whether the presence of lymphocyte aggregates could be a predictor of the clinical response at week 16. Furthermore, the effects of TNF blockade on lymphocyte aggregates were compared between patients with RA and patients with psoriatic arthritis (PsA). RESULTS: Fifty-seven percent of RA synovial tissue samples contained lymphocyte aggregates, and 32% of the patients had large aggregates. Aggregates were found in 67% of clinical responders compared with 38% of nonresponders. The presence of aggregates at baseline was a highly significant predictor of the clinical response to anti-TNF treatment (R(2) = 0.10, P = 0.008). Positivity for lymphocyte aggregates increased the power to predict the clinical response (R(2) = 0.29), when analyzed in a prediction model that included baseline disease activity evaluated by the Disease Activity Score in 28 joints, anti-cyclic citrullinated peptide antibody positivity, and synovial TNFalpha expression. There was a reduction in lymphocyte aggregates after anti-TNF antibody therapy in both RA and PsA. CONCLUSION: RA patients with synovial lymphocyte aggregates have, on average, a better response to infliximab treatment than those with only diffuse leukocyte infiltration. Moreover, the aggregation of synovial lymphocytes is reversible after anti-TNF antibody treatment.
21080021 Can simple ultrasonography predict the clinical effect of intra-articular injection therap 2011 Jun To investigate whether ultrasonographic joint assessment can predict the clinical response to intra-articular injection therapy of the knee. Patients with persistent gonarthritis intra-articularly received in a randomized double-blinded crossover fashion radiation synovectomy or a glucocorticoid injection, both followed by clinical bed rest. Prior to treatment and 3 months afterwards, grey-scale ultrasonography (US) of the knee was performed, measuring synovial thickness and extent of effusion. The final clinical effect of these two treatments was assessed at 3 months and finally at 6 months using a composite index. Ninety-seven patients, mainly suffering from undifferentiated arthritis (40%) or rheumatoid arthritis (31%), received 165 injections (including crossovers). Clinical effect at 6 months was not related to the baseline ultrasonographic extent of effusion or synovial thickness, nor with ultrasonographic decrease of effusion after the first 3 months. Nevertheless, it was associated with ultrasonographic decrease of synovial thickness within the first 3 months. Simple baseline US measurements fail to predict the final clinical effect of intra-articular treatment of the knee at 6 months, in contrast to early US changes of synovial thickness 3 months after therapy.
19565496 Small ubiquitin-like modifier 1 [corrected] mediates the resistance of prosthesis-loosenin 2009 Jul OBJECTIVE: To study the expression of small ubiquitin-like modifier 1 (SUMO-1) in aseptic loosening of prosthesis implants and to investigate its role in regulating the susceptibility of prosthesis-loosening fibroblast-like synoviocytes (FLS) to Fas-induced apoptosis. METHODS: Specimens of aseptically loosened tissue were obtained at revision surgery, and the expression of SUMO-1 was analyzed by in situ hybridization. SUMO-1 levels in FLS were determined by quantitative polymerase chain reaction and Western blot analysis. Immunohistochemistry and confocal microscopy were used to study the subcellular localization of SUMO-1. The functional role of SUMO-1 in Fas-induced apoptosis of prosthesis-loosening FLS was investigated by small interfering RNA-mediated knockdown of SUMO-1 and by gene transfer of the nuclear SUMO-specific protease SENP1. RESULTS: SUMO-1 was expressed strongly in aseptically loosened tissue and was found prominently at sites adjacent to bone. Prosthesis-loosening FLS expressed levels of SUMO-1 similar to the levels expressed by rheumatoid arthritis (RA) FLS, with SUMO-1 being found mainly in promyelocytic leukemia protein nuclear bodies. Knockdown of SUMO-1 had no effect on spontaneous apoptosis but significantly increased the susceptibility of prosthesis-loosening FLS to Fas-induced apoptosis. Gene transfer of the nuclear SUMO-specific protease SENP1 reverted the apoptosis-inhibiting effects of SUMO-1. CONCLUSION: These data suggest that SUMO-1 is involved in the activation of both RA FLS and prosthesis-loosening FLS by preventing these cells from undergoing apoptosis. Modification of nuclear proteins by SUMO-1 contributes to the antiapoptotic effects of SUMO-1 in prosthesis-loosening FLS, providing evidence for the specific activation of sumoylation during their differentiation. Therefore, SUMO-1 may be an interesting target for novel strategies to prevent aseptic prosthesis loosening.
21031477 Proteolysis activity of IgM antibodies from rheumatoid arthritis patients' sera: evidence 2010 Nov The IgM antibodies from rheumatoid arthritis (RA) patients' sera were screened for peptide hydrolyzing activity. Recovery of structurally intact IgM antibodies (Abs), in a single step, was achieved using a weak anion-exchange methacrylate monolith disk. The IgM Abs from patients' sera hydrolyzed the Pro-Phe-Arg-4-methyl-coumaryl-7-amide (PFR-MCA) substrate appreciably compared to the healthy donors. The apparent K(m) values of IgM Abs from patients' sera were between 0.4 and 0.7 mM. Furthermore, IgM Abs displayed 5 to 10-folds greater proteolysis activity than IgG Abs, recovered from the same pathological serum. The proteolysis activity, as a function, was found to be independent of IgM-RF titer value. Affinity labeling approach targeted at the catalytic site histidine was studied, using a specific irreversible inhibitor, N-α-tosyl-L-lysine chloromethyl ketone (TLCK). Despite modification of catalytic His, observation of serine protease like activity suggest presence of an atypical catalytic framework in a few pathological IgM Abs.
20056455 Outcome of total elbow replacement for rheumatoid arthritis: single surgeon's series with 2010 Apr BACKGROUND: The reported outcome of total elbow replacement is inferior to hip and knee arthroplasty, and there might be an element of institutional bias. METHODS: We analyzed the outcome of Souter and Coonrad-Morrey total elbow prosthesis in rheumatoid elbow performed by a single surgeon from a center independent from standpoint of being involved in the designing or manufacturing of the implant. RESULTS: We had 44 Souter elbows with a mean follow-up of 108 months and 55 Coonrad-Morrey elbows with mean follow-up of 60 months. The Mayo Elbow Performance Score was comparable in both the groups with similar subjective satisfaction. Souter elbow showed a survivorship of 92.9% at 5 years and 76% at 10 years, with aseptic loosening rate of 18% and instability of 9% as main reasons for the failure. The Coonrad-Morrey elbow shows 100% survival at mean follow-up of 5 years in our series. CONCLUSION: We find high rate of instability and loosening of Souter prosthesis with an inferior 5-year survival compared to Coonrad-Morrey prosthesis.
19632436 Extracorporeal membrane oxygenation-assisted resection of goiter causing severe extrinsic 2009 Aug We report a case of a 51-year-old woman with a huge multi-nodular thyroid goiter extending down into the superior mediastinum and causing severe extrinsic airway compression. Also due to the reason of severe rheumatoid arthritis, her mouth could not open widely. Because the endotracheal intubation was unsuccessful, we performed a subtotal thyroidectomy with the institution of veno-arterial extracorporeal membrane oxygenation.
20601610 Anti-TNF therapy, from rationale to standard of care: what lessons has it taught us? 2010 Jul 15 In the mid-1980s, new molecular tools enabled the biology of cytokine expression and regulation to be studied. Our group uncovered a TNF-dependent cascade in active rheumatoid synovium, suggesting that TNF might be a therapeutic target; this concept was supported in an animal model of the disease. The proof of concept was a series of clinical trials, which have led to marked changes in the therapy of human rheumatoid arthritis and subsequently of other diseases. The work with TNF clearly demonstrated the importance of cytokines in medicine as well as the capacity of mAbs (or receptor fusion proteins) to be used long-term in large populations, thus changing the therapeutic landscape.
21137068 MS analysis of rheumatoid arthritic synovial tissue identifies specific citrullination sit 2010 May PURPOSE: Citrullination is a post-translational modification of arginine residues to citrulline catalyzed by peptidyl arginine deiminases. Induced expression of citrullinated proteins are frequently detected in various inflammatory states including arthritis; however, direct detection of citrullination in arthritic samples has not been successfully performed in the past. EXPERIMENTAL DESIGN: Citrullination of human fibrinogen, a candidate autoantigen in arthritis, was studied. Accurate identification of citrullinated fibrinogen peptides from rheumatoid arthritis synovial tissue specimens was performed using accurate mass and retention time analysis. RESULTS: A peptide with the sequence ESSSHHPGIAEFPSRGK corresponding to amino acids 559-575 of fibrinogen α-chain was identified to be citrullinated with an occupancy rate between 1.4 and 2.5%. Citrullination of the peptide KREEAPSLRPAPPPISGGGYRARPAK corresponding to amino acids 52-77 of the fibrinogen β-chain was identified with an occupancy rate of 1.2%. CONCLUSIONS AND CLINICAL RELEVANCE: We report a proof of principle study for the identification of citrullinated proteins and within them, identification of citrullination sites and quantification of their occupancies in synovial tissue from rheumatoid arthritis patients using high-resolution MS. Detailed studies on which molecules are citrullinated in arthritis can provide information about their role in immune regulation and serve as novel biomarkers and potentially even as therapeutic targets.
19822038 How did ankylosing spondylitis become a separate disease? 2009 Jul Individual patients whose disease in retrospect is compatible with a diagnosis of ankylosing spondylitis (AS) began to be described in the 19th century, at a time when "rheumatism" comprised an undefined conglomeration of ailments. In the 1890s, rheumatoid arthritis (RA) began to be extricated from rheumatic fever and gout. But what criteria should delimit the diagnosis of RA? The first assistance came with the introduction of radiology in the first decade of the new century. By the 1930s, objective radiologic distinctions between RA and A S were being made, beginning with the preferential involvement of the sacroiliac joints in AS. The first useful serologic test was developed in the 1950s: "rheumatoid factor" that eventually is present in about three-fourths of cases of RA, but is absent in AS. In the 1970s discovery of clinical associations with specific histocompatibility antigens finalized the distinction between RA and AS with the discovery that one antigen, B-27, is associated ten times as frequently with AS than with RA, while it occurs no more frequently with RA than in the general population. Associations between B-27 and certain radiologic appearances has further been mutually confirmatory of their diagnostic significance.