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T Bardin

Publications and source records attributed to T Bardin.

At least 37 records · Page 2Linked to original sources

New susceptibility locus for rheumatoid arthritis suggested by a genome-wide linkage study.

Rheumatoid arthritis (RA), the most common autoimmune disease, is associated in families with other autoimmune diseases, including insulin-dependent diabetes mellitus (IDDM). Its genetic component has been suggested by familial aggregation (lambdas = 5), twin studies, and segregation analysis. HLA, which is the only susceptibility locus known, has been estimated to account for one-third of this component. The aim of this paper was to identify new RA loci. A genome scan was performed with 114 European Caucasian RA sib pairs from 97 nuclear families. Linkage was significant only for HLA (P < 2.5.10(-5)) and nominal for 19 markers in 14 other regions (P < 0.05). Four of the loci implicated in IDDM potentially overlap with these regions: the putative IDDM6, IDDM9, IDDM13, and DXS998 loci. The first two of these candidate regions, defined in the RA genome scan by the markers D18S68-D18S61-D18S469 (18q22-23) and D3S1267 (3q13), respectively, were studied in 194 additional RA sib pairs from 164 nuclear families. Support for linkage to chromosome 3 only was extended significantly (P = 0.002). The analysis of all 261 families provided a linkage evidence of P = 0. 001 and suggested an interaction between this putative RA locus and HLA. This locus could account for 16% of the genetic component of RA. Candidate genes include those coding for CD80 and CD86, molecules involved in antigen-specific T cell recognition. In conclusion, this first genome scan in RA Caucasian families revealed 14 candidate regions, one of which was supported further by the study of a second set of families.

Arthritis, Rheumatoid↗

The spondylarthropathies: classification and diagnosis. Do we need new terminologies?

The present classification of a number of arthropathies linked to the B27 antigen under the term spondylarthropathy emphasises the frequent familial aggregation and clustering during follow-up of these diseases. This article is an attempt to review the progress elicited by the introduction of classification criteria for spondylarthropathy and the limitations of the concept. In particular, we address the continued need for better understanding of aetiology and pathogenesis. This makes it likely that we will need new classifications in the future and that this will evolve along with improvements in disease understanding. Working classifications that include the infectious triggers and features of the host response might be useful to guide new approaches.

Humans↗

Medico-economic analysis of diacerein with or without standard therapy in the treatment of osteoarthritis.

This 9-month pragmatic study compared 2 therapeutic regimens in the management of osteoarthritis of the hip and knee. Patients received either diacerein 100 mg/day plus standard osteoarthritic therapy for 6 months, followed by a 3-month monitoring period without diacerein, or standard therapy alone for the entire 9-month period. A total of 207 patients with osteoarthritis of the knee and hip were enrolled. Improvements in Lequense's functional index and quality-of-life scores (revised Arthritis Impact Measurement Scales Health Status Questionnaire and Nottingham Health Profile), and decreases in nonsteroidal anti-inflammatory drug and analgesic consumption were significantly greater with diacerein plus standard therapy than with standard therapy alone. The overall assessment of therapy by patients was good or excellent for 60% of those who received diacerein plus standard therapy, compared with 26% who received standard therapy alone. Medical and paramedical procedures carried out in addition to those stipulated in the protocol (medical consultations, physiotherapy, nursing, etc.), osteoarthritis-related, were fewer and less costly in the diacerein plus standard therapy group than in the standard therapy group. The average outpatient cost (in 1995 French francs) of osteoarthritis treatment in the standard therapy group was FF2272 compared with FF2360 in the diacerein plus standard therapy group. The cost-effectiveness ratios per point scored on Lequesne's index were FF1893 for the standard therapy group and FF1072 for the diacerein plus standard therapy group, leading to a saving of 43% with diacerein plus standard therapy. The marginal cost (additional cost corresponding to the clinical benefit obtained by adding diacerein to standard treatment) was FF88 per point scored on Lequesne's index.

Aged↗

Magnetic resonance appearance of monoclonal gammopathies of unknown significance and multiple myeloma. The GRI Study Group.

STUDY DESIGN: A prospective multicenter study. OBJECTIVES: To evaluate the use of magnetic resonance imaging, in the differentiation between monoclonal gammopathies of unknown significance and multiple myeloma. SUMMARY OF BACKGROUND DATA: Although multiple myeloma has been studied extensively with magnetic resonance imaging, to the authors' knowledge, no study has evaluated the clinical interest of magnetic resonance imaging in the differentiation between monoclonal gammopathies of unknown significance and multiple myeloma. METHODS: The magnetic resonance examinations of the thoracolumbar spine in 24 patients with newly diagnosed monoclonal gammopathies of unknown significance were compared with those performed in 44 patients with newly diagnosed nontreated multiple myeloma. RESULTS: All findings on magnetic resonance examination performed in patients with monoclonal gammopathies of unknown significance were normal, whereas findings on 38 (86%) of the 44 magnetic resonance examinations performed in patients with multiple myeloma were abnormal. CONCLUSION: Magnetic resonance imaging can be considered as an additional diagnostic tool in differentiating between monoclonal gammopathies of unknown significance and multiple myeloma, which may be helpful when routine criteria are not sufficient. An abnormal finding on magnetic resonance examination in a patient with monoclonal gammopathies of unknown significance should suggest the diagnosis of multiple myeloma after other causes of marrow signal abnormalities are excluded. Magnetic resonance imaging also may be proposed in the long-term follow-up of monoclonal gammopathies of unknown significance when a new biologic or clinical event suggests the diagnosis of malignant monoclonal gammopathy.

Bone Marrow↗

[Epidemiological aspects of osteoarticular tuberculosis in adults. Retrospective study of 206 cases diagnosed in the Paris area from 1980 to 1994].

OBJECTIVES: The aim of this study was to determine the epidemiologic features of bone and joint tuberculosis in the Paris area from 1980 to 1994. METHODS: This retrospective study included 206 cases of confirmed bone and joint tuberculosis (in situ specimen) diagnosed from 1980 to 1994 in 7 hospital units (mainly rheumatology clinics) in Paris and suburban areas. RESULTS: The number of cases increased by a mean 12 per year from 1980 to 1989 then by 17 cases per year from 1990 to 1994. In both 1993 and 1994 there were 21 cases per year. The percentage of immigrant patients was 53% from 1980 to 1989 then reached 74% for 1990-1994, predominantly in subjects from black Africa. Only one patient in the series had human immunodeficiency virus (HIV) infection. A favoring factor was found in 23% of the immigrant and in 45% of the native French patients. Mean age was 37 years in immigrants and 58 years in French patients. Compared with French patients, immigrants had a higher rate of multifocal bone and joint tuberculosis, peripheral osteitis and spondylitus. CONCLUSION: Our findings suggest that the incidence of bone and joint tuberculosis has increased in Paris in 1993 and 1994. Two populations are especially susceptible: the elderly and/or immunodepressed French population and immigrants coming from endemic zones. The role or HIV infection was minimal in this predominantly rheumatology series.

Adult↗

Association of rheumatoid arthritis with an amino acid allelic variation of the T cell receptor.

OBJECTIVE: To investigate allelic variations of T cell receptor residues for a contribution to rheumatoid arthritis (RA) susceptibility. METHODS: We conducted an RA case-control study involving 1,579 northwest Europeans: 766 patients with erosive and rheumatoid factor-positive disease and 813 control subjects. Productive changes of segments TCRAV6S1, TCRAV7S1, TCRAV8S1, TCRAV10S2, and TCRBV6S1, TCRBV6S7 were investigated by single-strand conformation polymorphisms. The TCRAV8S1 association was confirmed by restriction fragment length polymorphism. RESULTS: In the systematic study (77 patients and 119 controls), an increase in 1 TCRAV8S1 genotype was found in the RA patients (P = 0.0004). This finding was replicated in 2 further populations, one from France (212 patients and 254 controls) and the other from Britain (477 patients and 440 controls), with a similar odds ratio (OR), which allowed pooling of the data and confirmation of the association (OR 1.3 [95% confidence interval 1.1-1.7], P = 0.008). CONCLUSION: These findings show evidence that TCRA is an RA susceptibility locus.

Alleles↗

Cryocrystalglobulinemia as a cause of systemic vasculopathy and widespread erosive arthropathy.

This report describes the case of woman who was admitted to the hospital for highly destructive axial and peripheral arthropathy in association with acute malignant hypertension and skin purpura. Type I IgGkappa serum cryoglobulinemia was identified and was classified as a monoclonal gammopathy of unknown significance. Cryoglobulin was shown to crystallize in the serum and synovium fluid and was responsible for both granulomatous microcrystalline synovial inflammation and occlusive vasculopathy in the kidneys and skin. Cryocrystalglobulinemia pathogenicity and therapeutic implications are discussed.

Arthrography↗

Inhibition and prevention of monosodium urate monohydrate crystal-induced acute inflammation in vivo by transforming growth factor beta1.

OBJECTIVE: We investigated the effects of transforming growth factor beta 1 (TGF beta 1) on monosodium urate monohydrate (MSU) crystal-induced acute inflammation in vivo. METHODS: One hour after MSU crystal-induced acute inflammation was produced in the rat subcutaneous air pouch model, the effects of recombinant human TGF beta 1 (rHuTGF beta 1; 10-100 pg/animal) and ultrapure TGF beta 1 (UPTGF beta 1; 100 and 500 pg/animal) were assessed, based on absolute and differential white blood cell counts in the exudate. The effects of 10 pg of rHuTGF beta 1 preincubated with a specific anti-TGF beta antibody, and the effects of coinjection of crystals and rHuTGF beta 1, were also studied. RESULTS: UPTGF beta 1 and rHuTGF beta 1 markedly reduced MSU crystal-induced inflammation. Recombinant human TGF beta 1 also reduced inflammation when administered concomitantly with MSU crystals. Moreover, rHuTGF beta 1 and UPTGF beta 1, injected 1 hour after MSU crystal injection, reduced the inflammatory response in a dose-dependent manner. Injection of rHuTGF beta 1 (100 pg/animal) resulted in a > 90% reduction in the maximal white blood cell count, achieved 6 hours after crystal injection. Preincubation of rHuTGF beta 1 with a specific anti-TGF beta 1 antibody significantly (P < 0.01) reversed the inhibitory effect of rHuTGF beta 1 on the inflammatory response. Consistent with the regulation of inflammatory cell recruitment into the joint, the percentage of monocytes markedly decreased (P < 0.01) following local injection with rHuTGF beta 1 6 hours after MSU crystal injection. CONCLUSION: Exogenous TGF beta 1 prevents and inhibits MSU crystal-induced acute inflammation in vivo. Its role in the self-limitation of gouty attacks deserves consideration, among the various other factors involved.

Acute Disease↗

Variation in the inflammatory properties of basic calcium phosphate crystals according to crystal type.

OBJECTIVE: To determine the inflammatory potential of basic calcium phosphate (BCP) crystals, which have been identified in human joints. METHODS: Hydroxyapatite, carbonate apatite, whitlockite, and octacalcium phosphate crystals were injected in rat air pouches. Volume and cellularity of the exudate were measured. Physicochemical properties of the injected BCP crystals were determined, and correlations with the magnitude of induced inflammatory responses were sought. RESULTS: Significant differences were observed among the volumes and white blood cell (WBC) counts of the pouch exudates, based on the various crystal types used to induce inflammation. A strong correlation was demonstrated between the specific surface (SS) area of the injected crystals and the area under the curve for induced WBC count versus time (R2 = 0.88, P = 0.05). This correlation was observed for SS area values below 50 m2/gm, but when SS area increased further, this parameter plateaued. Another parameter of inflammatory response was obtained by dividing the area under the curve figuring WBC counts versus time by the corresponding SS area for each crystal type. This parameter increased linearly with the Ca:P ratio (R2 = 0.97, P = 0.0003). CONCLUSION: The inflammatory potential of BCP crystals appeared to vary according to crystal features. SS area and the Ca:P ratio (which correlates with crystal solubility) influenced inflammatory properties. These results could explain the variable clinical consequences of BCP deposits, and must be taken into account in the choice of apatite ceramics for use as biomaterials.

Animals↗

Dialysis arthropathy: outcome after renal transplantation.

PURPOSE: Patients treated by long-term maintenance hemodialysis frequently develop a form of chronic arthropathy that is strongly associated with beta 2-microglobulin amyloid deposition and related, at least in part, to beta 2-microglobulin retention. Successful renal transplantation is followed by a rapid fall in serum beta 2-microglobulin levels and might allow dissolution of amyloid deposits. The purpose of this work was to investigate the effects of renal transplantation on dialysis arthropathy. PATIENTS AND METHODS: Fourteen renal transplant recipients were selected on the basis of previous hemodialysis treatment for at least 10 years (mean 16) and a history of chronic joint pain prior to transplantation. They all received 10 to 17.5 mg/d of prednisone. Posttransplant rheumatologic manifestations were studied prospectively and compared to pretransplant rheumatologic manifestations recorded in medical charts and reported during patient interviews. Pretransplant and posttransplant articular roentgenograms were separately analyzed by three observers who were blinded to timing of the films. Beta 2-microglobulin amyloid was identified by Congo red staining and immunohistology. RESULTS: After a mean posttransplant interval of 54 months (range 12 to 121), the articular condition was improved in 10 patients, unchanged in 1, and worsened in 3, according to patients' assessments. The number of painful joints decreased significantly (P < 0.05) as compared to the pretransplant period. However, the number and size of subchondral bone erosions remained unchanged, destructive arthropathies generally worsened, and articular beta 2-microglobulin amyloid deposits were identified in 2 patients, 2 and 10 years after renal transplantation, respectively. CONCLUSION: Renal transplantation appeared to arrest progression of beta 2-microglobulin amyloid in dialysis patients, but it neither led to dissolution of deposits nor prevented progression of destructive arthropathies. Most articular symptoms were improved, probably as a result of corticosteroid therapy.

Adult↗

Destructive arthropathy of the hands in chronic hemodialysis patients. A report of seven cases with pathological documentation.

Destructive arthropathy of the hands is common in chronic hemodialysis patients. The clinical and histological features in seven cases are reported. There were five females and two males aged 45 to 78 years. Hemodialysis duration at the time of surgery was 48 to 228 months (mean 92 months). Four patients had arthrodesis, two had insertion of silastic implants and one had a diagnostic surgical biopsy. The site of the surgical procedure was a distal interphalangeal joint in three patients, a proximal interphalangeal joint in one, a trapeziometacarpal joint in two, and both a proximal and a distal interphalangeal joints in one. All seven patients had severe destructive arthropathy responsible for pain and instability. Roentgenograms showed joint space obliteration and subchondral erosions or lysis, without osteophytosis. Several finger joints were involved in six of the seven patients. Histologic studies of the synovial membrane (n = 7) and subchondral bone (n = 4) found no amyloid even in the three patients with clinical or roentgenographic evidence of amyloidosis at other sites. Electron microscopy studies were done in two patients and failed to disclose crystals or amyloid. Our findings demonstrate that destructive arthropathy of the hands in hemodialysis patients is not a manifestation of dialysis-related amyloidosis. The pathophysiology of the condition remains poorly understood.

Aged↗

Plasma kinetics of 125I-labelled amyloid P component in beta 2M amyloidosis: a possible approach to quantitate disease activity.

Dialysis amyloidosis is one of the most incapacitating complications of long-term dialysis treatment. Quantitative assessment of amyloid deposition using radiolabelled tracers has been recently proposed but convincing evidence of its validity in uraemic patients remains to be provided. We studied the plasma kinetics of i.v. administered 125I-labelled serum amyloid P component (125I-SAP) in 20 chronic haemodialysis patients compared with those of nine healthy volunteers and three non-dialysed patients with systemic amyloidosis. Plasma clearance of the tracer was abnormal in 17 of 20 dialysis patients in whom plasma radioactivity declined in a bi-exponential mode, in contrast to the single-exponential slope observed in all healthy controls. 125I-SAP plasma half-life of the second component, probably reflecting metabolic clearance, was significantly prolonged in these dialysis patients compared with the healthy controls (35.3 versus 24.6 h, P < 0.001). Among the long-term haemodialysis patients the calculated extravascular distribution of 125I-SAP was significantly greater in those with severe arthropathy than in asymptomatic patients. These findings demonstrate for the first time that SAP clearance is disturbed in haemodialysis patients due to both failing renal elimination and retention in extravascular sites. The extravascular diffusion is greatly enhanced in patients with clinical evidence of amyloidosis. Therefore the study of plasma 125I-SAP kinetics promises to be a valuable tool to quantitate the extent of amyloidosis.

Adult↗