bluuebunny/crossref_metadata_2025_split huggingface dataset:
H‐ras oncogene point mutations in arthritic synovium
Authors: Roivainen Anne , Jalava Jari , Pirilä Laura , Yli‐Jama Tuomas , Tiusanen Hannu , Toivanen Paavo 
Published: February 2007

AbstractObjective. To examine mutational activation of ras proto‐oncogenes in synovial tissue from patients with rheumatoid arthritis (RA) compared with synovial specimens from patients with osteoarthritis (OA) or other arthropathies. Synovial samples from cadavers, without any signs of joint disease, were used as control material.Methods. Using a combination of polymerase chain reaction (PCR) and automated sequencing of the amplified PCR product, regions around codons 12, 13, and 61 of the H‐, K‐, and N‐ras proto‐oncogenes were analyzed. Confirmation of mutations was based on restriction fragment length polymorphism analysis and/or oligonucleotide hybridization.Results. Four (6%) of 72 patients with RA, 2 (13%) of 16 with OA, and 1 (8%) of 12 with other arthropathies harbored mutant H‐ras proto‐oncogenes, and were heterozygous at codon 13 for the GGT→GAT (Gly→Asp) change. An unexpected mutation was found in the H‐ras gene, in which a heterozygous GTG→ATG (Val→Met) mutation was observed over codon 14. The incidence for this mutation was 39% (28 of 72) in RA patients, 94% (15 of 16) in OA patients, and 42% (5 of 12) in patients with other arthropathies. All samples carrying the codon 13 mutation of H‐ras were also codon 14‐mutated, i.e., double mutations existed. Identical point mutations were also detected in a few synovial specimens obtained from cadavers (n = 8), including a single case of double mutation. All specimens showed normal K‐ and N‐ras loci.Conclusion. Activation of proto‐oncogene H‐ras by point mutation in codons 13 and 14 occurred in the synovial tissue of patients with RA, OA, or other arthropathies, as well as, to some extent, in the control synovia, indicating that the phenomenon is not specific for RA. In codon 14, incidence of the H‐ras point mutation was highest in OA tissue. The possible significance of this codon 14‐mutated H‐ras gene needs to be clarified.
Collagenase‐3 (matrix metalloprotease 13) is preferentially localized in the deep layer of human arthritic cartilage in situ. In vitro mimicking effect by transforming growth factor β
Authors: Moldovan Florina , Pelletier Jean‐Pierre , Hambor John , Cloutier Jean‐Marie , Martel‐Pelletier Johanne 
Published: February 2007

AbstractObjective. To examine, by immunohistochemistry, the localization and distribution of human collagenase‐3 in normal, osteoarthritis (OA), and rheumatoid arthritis (RA) cartilage, and to investigate the effects of interleukin‐1β (IL‐1β) and transforming growth factor β (TGFβ) on the synthesis and distribution of collagenase‐3.Methods. Human cartilage specimens were obtained from tibial plateaus. In the first series of experiments, the OA specimens were excised from fibrillated and nonfibrillated areas of cartilage, and RA specimens were excised from lesional areas, including the cartilage‐pannus junction when present. In the second series, full strips of cartilage were processed for culture in the presence or absence of IL‐1β (100 units/ml) or TGFβ (150 ng/ml). Each specimen was processed for immunohistochemical analysis using a collagenase‐3 monoclonal antibody.Results. The number of cells that stained for collagenase‐3 in normal cartilage was very low (±3%). In OA cartilage, the percentage increased dramatically, and no difference was found between fibrillated and nonfibrillated areas. A statistically significant increase in the percentage of cells staining for collagenase‐3 was found in the deep layer compared with the superficial layer. This finding was noted in both the fibrillated areas (mean ± SEM 58.4 ± 1.6% and 40.1 ± 3.9%, respectively; P < 0.007) and the nonfibrillated areas (55.4 ± 3.2% and 43.2 ± 2.7%; P < 0.01). Similarly, RA cartilage showed a statistically significant (P < 0.001) increase in the level of chondrocytes staining positive for collagenase‐3 in the deep layers (46.4 ± 4.1%) compared with the superficial layers (26.2 ± 3.4%). In these RA specimens, the numbers of positively staining chondrocytes were similar both close to and at a distance from the pannus junction. Both IL‐1β and TGFβ increased the number of chondrocytes producing collagenase‐3. Interestingly, in normal specimens, TGFβ had a predominant effect in the deep layers, while IL‐1β had a greater effect on the superficial layers.Conclusion. This study demonstrates that, in situ, the increase in the level of chondrocytes synthesizing collagenase‐3 in arthritic cartilage is predominant in the deep layers. The results further indicate that TGFβ can up‐regulate the level of this enzyme and, in normal cartilage in vitro, can cause a mimicking of the in situ distribution observed in arthritic cartilage.
Testosterone suppresses anti‐DNA antibody production in peripheral blood mononuclear cells from patients with systemic lupus erythematosus
Authors: Kanda Naoko , Tsuchida Tetsuya , Tamaki Kunihiko 
Published: February 2007

AbstractObjective. To study the in vitro effect of testosterone on anti‐DNA antibody production in peripheral blood mononuclear cells (PBMC) from patients with systemic lupus erythematosus (SLE) in order to elucidate its regulatory role in SLE.Methods. PBMC from SLE patients were cultured with testosterone. IgG anti‐double‐stranded DNA (anti‐dsDNA) antibody, total IgG, and cytokine activity in the supernatants were measured by enzyme‐linked immunosorbent assay.Results. Testosterone suppressed both IgG anti‐dsDNA antibody and total IgG production in PBMC from SLE patients. Antibody production in B cells was also suppressed by testosterone, although the magnitude of its effect on B cells was lower than that on PBMC. Interleukin‐6 (IL‐6) partially restored the testosterone‐induced decrease in antibody levels in PBMC. Testosterone reduced IL‐6 production in monocytes.Conclusion. These results suggest that testosterone may directly suppress anti‐DNA antibody production in PBMC from SLE patients by inhibiting B cell hyperactivity and, indirectly, by down‐regulating IL‐6 production in monocytes. These results support the therapeutic effects of testosterone on SLE.
FAS/FAS ligand expression and induction of apoptosis in chondrocytes
Authors: Hashimoto Sanshiro , Setareh Morteza , Ochs Robert L. , Lotz Martin 
Published: February 2007

AbstractObjective. To examine the expression of Fas/Fas ligand and the role of this ligand/receptor interaction in the regulation of apoptosis in normal human articular chondrocytes and in osteoarthritis (OA) cartilage.Methods. Normal and OA human knee cartilage and cells isolated from these tissues were tested for Fas expression by flow cytometry. Induction of apoptosis by antibody to Fas was analyzed by DAPI staining and electron microscopy.Results. Treatment of freshly isolated normal human articular chondrocytes with an agonistic Fas antibody induced apoptosis in a subpopulation (‐20%) of the cells. Apoptosis induced by anti‐Fas was not dependent on nitric oxide (NO), and anti‐Fas also did not induce NO production. Analysis of isolated cells demonstrated similar levels of Fas expression on normal and OA chondrocytes (28% and 32%, respectively). In normal articular cartilage, Fas‐positive cells were located mainly in the superficial and midzones. In contrast, in fibrillated OA cartilage, surface layers were partially absent and Fas‐expressing cells were also detected in the deeper layers. Fas ligand messenger RNA was not detectable in resting or activated normal or OA chondrocytes. Analysis by electron microscopy showed the nuclear and cytoplasmic changes typical of apoptosis in cultures treated with antibody to Fas.Conclusion. A subpopulation of chondrocytes expresses Fas and is susceptible to Fas‐induced apoptosis. Fas‐mediated chondrocyte apoptosis may contribute to cartilage degradation in arthritis.
Posttranscriptional regulation of collagenase‐1 gene expression in synoviocytes by adenosine receptor stimulation
Authors: Boyle David L. , Han Zuoning , Rutter Joni L. , Brinckerhoff Constance E. , Firestein Gary S. 
Published: February 2007

AbstractObjective. To characterize the transcriptional and posttranscriptional regulation of collagenase‐1 by adenosine receptor stimulation in interleukin‐1 (IL‐1)‐stimulated fibroblast‐like synoviocytes (FLS).Methods. FLS were stimulated with IL‐1 and either the nonselective adenosine agonist 5′‐N‐ethylcarboxamidoadenosine (NECA) or the adenylate cyclase activator forskolin. Electrophoretic mobility shift assays were performed to determine AP‐1 and cAMP‐responsive element binding protein (CREB) activation. Transcriptional activation was determined by transfecting HS68 dermal fibroblasts with a collagenasechloramphenicol acetyltransferase construct. Finally, collagenase messenger RNA (mRNA) half‐life was determined by activating cells in the presence of IL‐1, IL‐1 + NECA, or IL‐1 + forskolin and culturing cells in the presence of actinomycin D.Results. NECA and forskolin had no effect on AP‐1 activation, c‐jun or c‐fos gene expression, or CREB phosphorylation. IL‐1 markedly increased collagenase promoter activity, and neither NECA nor forskolin blocked this action. Studies of mRNA half‐life showed that both NECA and forskolin decreased the half‐life of collagenase mRNA in IL‐1‐stimulated FLS and HS68 cells.Conclusion. The findings of this study demonstrate that NECA and forskolin decrease collagenase gene expression in FLS and dermal fibroblasts due to enhanced mRNA degradation.
A linkage study across the T cell receptor A and T cell receptor B loci in families with rheumatoid arthritis
Authors: Hall F. C. , Brown M. A. , Weeks D. E. , Walsh S. , Nicod A. , Butcher S. , Andrews L. J. , Wordsworth B. P. 
Published: February 2007

AbstractMethods. A linkage study was performed in 184 RA families from the UK Arthritis and Rheumatism Council Repository, each containing at least 1 affected sibpair. The microsatellites D14S50, TCRA, and D14S64 spanning the TCRA locus and D7S509, Vβ6.7, and D7S688 spanning the TCRB locus were used as DNA markers. The subjects were genotyped using a semiautomated polymerase chain reaction‐based method. Twopoint and multipoint linkage analyses were performed.Results. Nonparametric single‐marker likelihood odds (LOD) scores were 0.49 (P = 0.07) for D14S50, 0.65 (P = 0.04) for TCRA, 0.07 (P = 0.29) for D14S64, 0.01 (P = 0.43) for D7S509, 0.0 (P = 0.50) for Vβ6.7, and 0.0 (P = 0.50) for D7S688. By multipoint analysis, there was no evidence of linkage at TCRB (LOD score 0), and the maximum LOD score at the TCRA locus was 0.37 (at D14S50). The presence of a susceptibility locus (LOD score < −2.0) was excluded, with lambda ≥ 1.8 at TCRA and ≥ 1.4 at TCRB.Conclusion. These linkage studies provide no significant evidence of a major germline‐encoded TCRA or TCRB component of susceptibility to RA.
Increased nitric oxide production accompanied by the up‐regulation of inducible nitric oxide synthase in vascular endothelium from patients with systemic lupus erythematosus
Authors: Belmont H. Michael , Levartovsky David , Goel Archana , Amin Ashok , Giorno Ralph , Rediske John , Skovron Mary Louise , Abramson Steven B. 
Published: February 2007

AbstractObjective. To investigate whether systemic lupus erythematosus (SLE) is accompanied by increased serum nitrite levels, whether active compared with inactive disease is associated with greater nitric oxide (NO) production, and whether endothelial cells or keratinocytes serve as cellular sources of NO by virtue of their increased expression of either constitutive nitric oxide synthase (cNOS) or inducible NOS (iNOS).Methods. Fifty‐one serum samples (46 from patients with SLE) were analyzed for NO production by measuring nitrite levels in a calorimetric assay. Skin biopsy samples from 21 SLE patients and 11 healthy volunteers were evaluated immunohistochemically, using monoclonal antibodies, for endothelial cell and keratinocyte cNOS and iNOS expression.Results. Serum nitrite levels were significantly elevated in the 46 patients with SLE (mean ± SEM 37 ± 6 μM/liter) compared with controls (15 ± 7 μM/liter; P < 0.01), and were elevated in patients with active SLE compared with those with inactive disease (46 ± 7 μM/liter versus 30 ± 7 μM/liter; P < 0.01). Serum nitrite levels correlated with disease activity (r = 0.47, P = 0.04) and with levels of antibodies to doublestranded DNA (r = 0.35, P = 0.02). Endothelial cell expression of iNOS in SLE patients (mean ± SEM score 1.5 ± 0.2) was significantly greater compared with controls (0.6 ± 0.2; P < 0.01), and higher in patients with active disease compared with those with inactive SLE (1.7 ± 0.2 versus 1.2 ± 0.2; P < 0.01). Keratinocyte expression of iNOS was also significantly elevated in SLE patients (0.9 ± 0.1) compared with controls (0.4 ± 0.1; P < 0.001). With regard to expression of cNOS, there were no differences between patients with active SLE, those with inactive SLE, and normal controls in either the vascular endothelium or the keratinocytes.Conclusion. NO production is increased in patients with SLE, and 2 potential sources of excessive NO are activated endothelial cells and keratinocytes via up‐regulated iNOS.
Susceptibility to ankylosing spondylitis in twins the role of genes, HLA, and the environment
Authors: Brown Matthew A. , Kennedy L. Gail , Macgregor Alex J. , Darke Chris , Duncan Emma , Shatford Jane L. , Taylor Andrew , Calin Andrei , Wordsworth Paul 
Published: February 2007

AbstractObjective. To determine the relative effects of genetic and environmental factors in susceptibility to ankylosing spondylitis (AS).Methods. Twins with AS were identified from the Royal National Hospital for Rheumatic Diseases database. Clinical and radiographic examinations were performed to establish diagnoses, and disease severity was assessed using a combination of validated scoring systems. HLA typing for HLA‐B27, HLA‐B60, and HLA‐DR1 was performed by polymerase chain reaction with sequence‐specific primers, and zygosity was assessed using microsatellite markers. Genetic and environmental variance components were assessed with the program Mx, using data from this and previous studies of twins with AS.Results. Six of 8 monozygotic (MZ) twin pairs were disease concordant, compared with 4 of 15 B27‐positive dizygotic (DZ) twin pairs (27%) and 4 of 32 DZ twin pairs overall (12.5%). Nonsignificant increases in similarity with regard to age at disease onset and all of the disease severity scores assessed were noted in disease‐concordant MZ twins compared with concordant DZ twins. HLA‐B27 and B60 were associated with the disease in probands, and the rate of disease concordance was significantly increased among DZ twin pairs in which the co‐twin was positive for both B27 and DR1. Additive genetic effects were estimated to contribute 97% of the population variance.Conclusion. Susceptibility to AS is largely genetically determined, and the environmental trigger for the disease is probably ubiquitous. HLA‐B27 accounts for a minority of the overall genetic susceptibility to AS.
Clinical, laboratory, radiographic, and histopathologic features of methotrexate‐associated lung injury in patients with rheumatoid arthritis. A multicenter study with literature review
Authors: Kremer Joel M. , Alarcón Graciela S. , Weinblatt Michael E. , Kaymakcian Mari V. , Macaluso Maurizio , Cannon Grant W. , Palmer William R. , Sundy John S. , St. Clair E. William , Alexander Ronald W. , Smith G. J. Walker , Axiotis Constantine A. 
Published: February 2007

AbstractObjective. To describe the clinical, laboratory, radiologic, and histopathologic features of methotrexate (MTX)‐induced lung injury in a combined cohort of selected patients with rheumatoid arthritis (RA) and all cases reported in the English‐language literature.Methods. Retrospective combined cohort review and abstraction from the medical literature. Case reports were obtained from 6 centers that had 4 or more cases of potential MTX lung injury per site. RA patients who were seen between 1981 and 1993 and who satisfied predetermined criteria for the presence of MTX lung injury were identified.Results. Twenty‐seven patients satisfied the criteria for definite MTX lung injury, and 2 for probable MTX lung injury. Predominant clinical features of MTX lung injury included shortness of breath in 27 patients (93.1%), which was present for 23.5 ± 22.3 days (mean ± SD), cough in 24 (82.8%), present for 26.9 ± 28.5 days, and fever in 20 (69.0%), present for 10.4 ± 12.8 days. Five patients (17.2%) died, compared with 12 of 68 (17.6%) reported in the medical literature. Four of the 6 patients who were re‐treated with MTX after an initial pulmonary event developed recurrent lung toxicity, resulting in 2 deaths, compared with a recurrence rate of 3 of 6 in the literature.Conclusion. MTX lung injury is most often a subacute process, in which symptoms are commonly present for several weeks before diagnosis. Approximately 50% of the cases are diagnosed within 32 weeks from initiation of MTX treatment. A patient who recovers from MTX lung injury should not be re‐treated. Earlier recognition and drug withdrawal may avoid the serious and sometimes fatal outcome that has been observed in this and other studies.
Combination treatment of severe rheumatoid arthritis with cyclosporine and methotrexate for forty‐eight weeks. An open‐label extension study
Authors: Stein C. Michael , Pincus Theodore , Yocum David , Tugwell Peter , Wells George , Gluck Oscar , Kraag Gunnar , Torley Helen , Tesser John , McKendry Robert , Brooks Raye H. ,   The Methotrexate‐Cyclosporine Combination Study Group
Published: February 2007

AbstractObjective. To determine whether the clinical benefit and favorable safety profile previously noted with the combination of cyclosporine (CSA) and methotrexate (MTX) given for 24 weeks in patients with rheumatoid arthritis (RA) would be maintained for a further 24 weeks, and whether the addition of CSA in patients who had previously been randomized to receive placebo + MTX would result in clinical benefit.Methods. Eligible subjects from the initial study (weeks 0–24), in which the addition of placebo or CSA to MTX therapy was compared in patients with RA that was partially responsive to MTX, were enrolled. Patients who had received CSA + MTX continued this regimen for a further 24 weeks (weeks 24–48) (group 1; n = 48), and patients who had initially received placebo + MTX now received CSA + MTX for 24 weeks (weeks 24–48) (group 2; n = 44), in an open‐label extension study. The primary outcome measures were the number of tender joints, number of swollen joints, physician and patient global assessments, pain, functional disability as measured by the modified Health Assessment Questionnaire, and erythrocyte sedimentation rate.Results. Of the 92 patients enrolled, 80 (87%) completed the extension study. In patients in group 1, the clinically and statistically significant improvement in response outcomes previously noted at week 24, ranging from 25% to 50%, was maintained through week 48. In patients in group 2, the addition of CSA resulted in significant clinical improvement. By week 48, most outcome measures in group 2 patients were similar to those in group 1 patients. CSA treatment resulted in a small increase in serum creatinine levels, but only 1 patient was withdrawn from the study for this reason.Conclusion. The clinical improvement previously observed in patients treated with the CSA + MTX combination for 24 weeks was maintained for 24 subsequent weeks, without serious adverse effects, and was also observed in the patients whose treatment was switched from placebo + MTX to CSA + MTX.
Percutaneous needle muscle biopsy in the evaluation of patients with suspected inflammatory myopathy
Authors: Campellone Joseph V. , Lacomis David , Giuliani Michael J. , Oddis Chester V. 
Published: February 2007

AbstractObjective. To determine the usefulness of a unique method of percutaneous needle muscle biopsy (NMB) in patients with suspected idiopathic inflammatory myopathy (IIM).Methods. The yield of percutaneous NMB was studied in 55 patients who were found to have a combination of clinical, laboratory, or electromyographic features of IIM.Results. A diagnosis of IIM was confirmed histopathologically in 29 patients (53%), other specific myopathies were found in 5 (9%), nonspecific myopathic changes were present in 11 (20%), and a neurogenic process was diagnosed in 3 (5%). Nonspecific changes or no abnormalities were present in 7 patients (13%). Followup of the 18 patients with nonspecific histopathologic findings disclosed that only 3 had a subsequent disease course compatible with IIM.Conclusion. Percutaneous NMB is a safe, convenient, and relatively inexpensive method of muscle biopsy, with a high diagnostic yield for the pathologic confirmation of IIM. It should be considered as a primary method of acquiring muscle for histopathologic examination in the evaluation of suspected IIM.
Azathioprine‐induced severe pancytopenia due to a homozygous two‐point mutation of the thiopurine methyltransferase gene in a patient with juvenile HLA‐B27‐associated spondylarthritis
Authors: Leipold G. , Schütz E. , Haas J. P. , Oellerich M. 
Published: February 2007

AbstractSevere pancytopenia due to azathioprine (AZA) toxicity in patients with autoimmune diseases is not uncommon. We describe a 14‐year‐old girl with HLA‐B27+ spondylarthritis who was treated with AZA 3 mg/kg/day and who suddenly developed severe pancytopenia in the seventh week of treatment. Analysis of the catabolic pathway of AZA revealed a homozygous deficiency of thiopurine methyltransferase (TPMT) on the basis of a combined 2‐point mutation at nucleotide positions 460 and 719 in the gene for TPMT, causing a toxic level of the metabolic active 6‐thioguanine nucleotides (6‐TGN) (2,394 pmoles/8 × 108 red blood cells). The patient was transfusion dependent and finally recovered 8 weeks after the development of the pancytopenia. At that time, 6‐TGN had already returned to normal therapeutic levels. Family studies revealed another homozygous deficiency in the mother, while the other family members were heterozygous.