bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased expression of type I collagen induced by microfibril‐associated glycoprotein 2: Novel mechanistic insights into the molecular basis of dermal fibrosis in scleroderma
Authors: Lemaire Raphael , Korn Joseph H. , Shipley J. Michael , Lafyatis Robert 
Published: June 2005

AbstractObjectiveMutations in fibrillin 1, a key component of extracellular microfibrils, are associated with connective tissue disorders such as Marfan's syndrome or skin fibrosis in the tight skin mouse model of scleroderma. Previous studies have suggested that fibrillin 1 mediates skin fibrosis via its interface with associated microfibrillar proteins and type I collagen; in particular, microfibril‐associated glycoprotein 2 (MAGP‐2), an extracellular matrix protein that binds to fibrillins and the αvβ3 integrin, is increased in TSK mouse and human scleroderma skin. Because the function of MAGP‐2 in the biologic processes of the matrix remains unknown, this study investigated whether MAGP‐2 regulates type I collagen.MethodsFibroblast cultures conditionally overexpressing MAGP‐2 were developed. Cells were analyzed by Western blotting, Northern blotting, pulse‐chase analysis, and immunofluorescence to assess the effect of MAGP‐2 on type I collagen.ResultsCells overexpressing MAGP‐2 formed increased MAGP‐2 matrix and showed a 3‐fold increase in intracellular type I procollagen. This increase was associated with increased levels of type I collagen in the medium and matrix. Increased type I collagen colocalized with the MAGP‐2 matrix. MAGP‐2 overexpression had no effect on type I procollagen messenger RNA, but markedly increased the half‐life of type I procollagen. MAGP‐2 induced type I collagen even under conditions in which no MAGP‐2 matrix was detectable, and did not require the presence of the RGD motif of MAGP‐2 in its integrin‐binding site.ConclusionThis study shows that MAGP‐2 stabilizes type I procollagen, identifying an important function of MAGP‐2 in extracellular matrix homeostasis. It also suggests that MAGP‐2 might mediate skin fibrosis in TSK mice and in patients with scleroderma.
Association of CXCL13 and CCL21 expression with the progressive organization of lymphoid‐like structures in Sjögren's syndrome
Authors: Barone F. , Bombardieri M. , Manzo A. , Blades M. C. , Morgan P. R. , Challacombe S. J. , Valesini G. , Pitzalis C. 
Published: June 2005

AbstractObjectiveEctopic lymphoneogenesis can occur in the salivary glands of Sjögren's syndrome (SS) patients and is associated with local antigen‐driven B cell responses, autoantibody formation, and potential lymphomatous transformation. CXCL13 and CCL21 have been identified in salivary glands, but their role in ectopic lymphoneogenesis in SS remains unclear. This study aimed to evaluate the microanatomic association between CXCL13 and CCL21 expression and the acquisition of lymphoid features in periductal foci.MethodsSalivary glands from 37 SS patients and 9 chronic sialadenitis patients were analyzed by immunohistochemistry for T cell/B cell segregation, CD21+ follicular dendritic cell networks, and peripheral lymph node addressin (PNAd)–positive high endothelial venules (HEVs) in relationship to the size of the aggregates and the expression of CXCL13 and CCL21 within infiltrating cells, epithelium, and endothelium.ResultsGrade 1 aggregates (10–50 lymphocytes) demonstrated predominance of nonorganized CD3+ cells, while grade 2 (>50 lymphocytes) and grade 3 (>50 with germinal centers) showed a progressive increase in CD20+ B cells and T cell/B cell segregation. This higher degree of lymphoid organization was significantly related to an increased expression of CXCL13 within infiltrating cells and PNAd+ HEV–associated CCL21‐producing cells. Conversely, no association between lymphoid organization and lymphoid chemokine expression by epithelial cells was observed.ConclusionThe acquisition of lymphoid features by inflammatory foci in SS is critically associated with the enlargement of the inflammatory foci and with the expression of CXCL13 and CCL21 within the infiltrate, but is not associated with their expression by epithelial cells. These data strongly support an active participation of CXCL13 and CCL21 in regulating the progressive organization and maintenance of periductal foci.
Reduced capacity for the reactivation of glucocorticoids in rheumatoid arthritis synovial cells: Possible role of the sympathetic nervous system?
Authors: Schmidt Martin , Weidler Claudia , Naumann Heidrun , Anders Sven , Schölmerich Jürgen , Straub Rainer H. 
Published: June 2005

AbstractObjectiveCortisol, the biologically active glucocorticoid, is a major endogenous antiinflammatory factor in rheumatoid arthritis (RA). The aim of this study was to examine the local conversion of cortisol to biologically inactive cortisone and vice versa (the cortisol–cortisone shuttle) in RA and osteoarthritis (OA) patients.MethodsThin‐layer chromatography and phosphorimaging were used to examine the cortisol–cortisone shuttle in mixed synovial cells. Double immunohistochemistry was used to assess the key enzymes 11β‐hydroxysteroid dehydrogenase 1 (11β‐HSD1) and 11β‐HSD2 and their possible cellular locations.ResultsDouble immunohistochemistry demonstrated 11β‐HSD1/2+ macrophages in the sublining area. The ratio of 11β‐HSD2+ cells to 11β‐HSD1+ cells was significantly higher in RA than in OA patients. Cortisol was converted to inactive cortisone in mixed synovial cells from RA and OA patients, which was largely inhibited by carbenoxolone (11β‐HSD1 and 11β‐HSD2 inhibitor). Using metyrapone to inhibit the 11β‐HSD1 reducing reaction (cortisone → cortisol), we demonstrated that the capacity for reactivation of cortisone to cortisol was significantly higher in OA than in RA patients. Although the capacity for the cortisone–cortisol shuttle was higher in synovial cells from less‐inflamed OA tissue compared with inflamed RA tissue, it was obvious that synovial inflammation in RA, but not OA, was related positively to the reactivation of cortisone. This indicates that in RA, a cause other than typical inflammatory factors inhibits the reactivation of cortisone. Since isoproterenol and adenosine inhibited the cortisol–cortisone shuttle, the loss of sympathetic nerve fibers (loss of β‐adrenergic agonist and adenosine) may be the missing link that accounts for the increased cortisol–cortisone shuttle in RA.ConclusionThis study demonstrates a reduced capacity for local reactivation of cortisone in RA synovial cells. Since synthetic glucocorticoids also use this reactivation shuttle, the results also apply to therapeutic glucocorticoids. This defective reactivation of cortisone may be an important unrecognized pathophysiologic factor in RA.
Granzyme B is dispensable for immunologic tolerance to self in a murine model of systemic lupus erythematosus
Authors: Graham Kareem L. , Thibault Donna L. , Steinman Jonathan B. , Okeke Lance , Kao Peter N. , Utz Paul J. 
Published: June 2005

AbstractObjectiveProteolytic autoantigen cleavage by the serine protease granzyme B has been implicated in the development of systemic autoimmune disease; however, there has been no conclusive demonstration of a pathogenic role for granzyme B in autoimmunity. In this study, we evaluated the role of granzyme B in a murine model of autoimmunity.MethodsTo identify potential novel granzyme B substrates, complementary DNAs encoding nuclear factor 45 (NF45) and NF90 were used to generate 35S‐methionine–labeled proteins by coupled in vitro transcription/translation. Radiolabeled proteins were then incubated with purified recombinant granzyme B or caspases, and the cleavage products were analyzed by autoradiography. We also immunized granzyme B–deficient and granzyme B–intact mice with the mineral oil pristane. Production of autoantibodies directed against granzyme B substrates in response to pristane was evaluated by Western blotting, immunoprecipitation, and enzyme‐linked immunosorbent assay.ResultsThe double‐stranded RNA–binding protein NF90 was identified as a novel substrate for caspases and granzyme B, both in vitro and in vivo. NF90 is uniquely cleaved by granzyme B in vitro; however, pristane immunization still induced anti‐NF90 antibodies in granzyme B–deficient mice. Pristane‐treated granzyme B–deficient mice also produced antibodies directed against the U1–70‐kd antigen, a previously identified granzyme B substrate. Last, antibodies directed against U1–70 kd arose spontaneously in granzyme B–deficient mice.ConclusionThese results demonstrate that granzyme B is not required for the production of autoantibodies directed against antigens that are granzyme B substrates in vitro. The data also suggest a protective role for this proapoptotic protease in systemic autoimmunity.
Arthritogenic anti–type II collagen antibodies are pathogenic for cartilage‐derived chondrocytes independent of inflammatory cells
Authors: Amirahmadi S. Fatemah , Whittingham Senga , Crombie Duncan E. , Nandakumar Kutty Selva , Holmdahl Rikard , Mackay Ian R. , van Damme Marie‐Paule , Rowley Merrill J. 
Published: June 2005

AbstractObjectiveSome monoclonal antibodies (mAb) to type II collagen (CII) are arthritogenic upon passive transfer to mice. We undertook this study to investigate whether such mAb are pathogenic in the absence of mediators of inflammation.MethodsThe arthritogenic mAb CIIC1 and M2139, and the nonarthritogenic mAb CIIF4, each reactive with a distinct and well‐defined conformational epitope on CII, were compared with control mAb GAD6. Bovine chondrocytes were cultured with one of the mAb, and on days 3, 6, and 9, antibody binding by chondrocytes and newly synthesized extracellular matrix (ECM) was examined by immunofluorescence, morphologic effects were studied by electron microscopy, and synthesis of matrix components was determined by metabolic labeling with 3H‐proline for collagen and 35S‐sulfate for proteoglycans.ResultsAll 3 mAb to CII bound to the matrix. CIIC1 and M2139 adversely affected the cultures, whereas CIIF4 did not. CIIC1 caused disorganization of CII fibrils in the ECM without affecting chondrocyte morphology, and increased matrix synthesis. M2139 caused thickening and aggregation of CII fibrils in the ECM and abnormal chondrocyte morphology but matrix synthesis was unaffected.ConclusionThe unique arthritogenic capacity of particular anti‐CII mAb upon passive transfer could be explained by their adverse, albeit differing, effects in primary cultures of chondrocytes. Such effects occur independent of inflammation mediators and are related to the epitope specificity of the mAb. Interference with the structural integrity of CII could precede, and even initiate, the inflammatory expression of disease.
Regulation of arthritis by p53: Critical role of adaptive immunity
Authors: Šimelyte Egle , Rosengren Sanna , Boyle David L. , Corr Maripat , Green Douglas R. , Firestein Gary S. 
Published: June 2005

AbstractObjectiveThe p53 tumor‐suppressor protein is expressed in rheumatoid arthritis synovium, and loss of p53 function through somatic mutation can occur in longstanding disease. Previous studies demonstrated that p53 is protective in murine collagen‐induced arthritis (CIA). To determine if adaptive immune responses or synovial effector functions are responsible for this effect, passive models of arthritis were studied in p53 wild‐type and knockout mice.MethodsModels of passive CIA, passive K/BxN serum transfer arthritis, and active CIA were induced in DBA/1 p53−/− or p53+ mice. Hind paws were evaluated for histologic evidence of inflammation and joint destruction. Synovial interleukin‐6 and matrix metalloproteinases 3 and 13 gene expression was analyzed by real‐time quantitative polymerase chain reaction. To evaluate T cell function in p53−/− mice, draining lymph node (LN) cells from mice immunized with type II collagen (CII) were evaluated in vitro.ResultsIncreased disease severity in p53−/− mice was confirmed in the standard CIA model. However, clinical arthritis, joint destruction, and synovial gene expression in the passive CIA and K/BxN serum transfer arthritis models were similar in p53−/− and p53+ mice. To determine if the p53 effect was related to T cell function, LN cells from CII‐immunized mice were isolated and stimulated with antigen in vitro. CII‐stimulated T cell proliferation and interferon‐γ production were significantly higher in p53−/− mice. An independent assessment of Th1 function using the cutaneous delayed‐type hypersensitivity model confirmed that p53−/− mice have enhanced T cell responses in vivo.ConclusionAdaptive immune responses, rather than antibody‐mediated responses, in p53−/− mice account for increased disease severity in the active CIA model.
A comparative assessment of alignment angle of the knee by radiographic and physical examination methods
Authors: Kraus Virginia B. , Vail T. Parker , Worrell Ted , McDaniel Gary 
Published: June 2005

AbstractObjectiveTo compare the knee‐alignment angle from a full‐limb radiograph (mechanical axis) with the anatomic‐axis angle as measured by physical examination using a goniometer and by 2 other radiographic methods.MethodsThe knee‐alignment angle was measured in 114 knees of 57 subjects who had radiographic osteoarthritis (OA), with a Kellgren/Lawrence grade of ≥1 in at least one knee. The mechanical axis was defined as the angle formed by the intersection of 2 lines, one from the center of the head of the femur to the center of the tibial spines, and a second from the center of the talus to the center of the tibial spines. The anatomic axis was defined as the angle formed by 2 lines, each originating from a point bisecting the femur and tibia and converging at the center of the tibial spine tips. The anatomic‐axis angle was measured by 3 methods: 1) physical examination using a goniometer, 2) a posteroanterior (PA) fixed‐flexion knee radiograph (anatomicPA axis), and 3) an anteroposterior (AP) full‐limb radiograph (anatomicAP axis).ResultsSignificant correlations were found between the mechanical‐axis angle and the anatomic‐axis angle measured by each of the 3 methods: by goniometer (r = 0.70, P < 0.0001), by anatomicPA axis (r = 0.75, P < 0.0001), and by anatomicAP axis (r = 0.65, P < 0.0001). The anatomic axis was offset a mean 4.21° valgus from the mechanical axis (3.5° in women, 6.4° in men), which was consistent across all methods.ConclusionKnee alignment assessed clinically by goniometer or measured on a knee radiograph is correlated with the angle measured on the more cumbersome and costly full‐limb radiograph. These alternative measures have the potential to provide useful information regarding the risk of progression of knee OA when a full‐limb radiograph is not available.
Activation of the endoplasmic reticulum stress response in autoimmune myositis: Potential role in muscle fiber damage and dysfunction
Authors: Nagaraju Kanneboyina , Casciola‐Rosen Livia , Lundberg Ingrid , Rawat Rashmi , Cutting Shawna , Thapliyal Rachana , Chang Jason , Dwivedi Sunita , Mitsak Megan , Chen Yi‐Wen , Plotz Paul , Rosen Antony , Hoffman Eric , Raben Nina 
Published: June 2005

AbstractObjectiveThe etiology and pathogenesis of human inflammatory myopathies remain unclear. Findings of several studies suggest that the degree of inflammation does not correlate consistently with the severity of clinical disease or of structural changes in the muscle fibers, indicating that nonimmune pathways may contribute to the pathogenesis of myositis. This study was undertaken to investigate these pathways in myositis patients and in a class I major histocompatibility complex (MHC)–transgenic mouse model of myositis.MethodsWe examined muscle tissue from human myositis patients and from class I MHC–transgenic mice for nonimmune pathways, using biochemical, immunohistochemical, and gene expression profiling assays.ResultsUp‐regulation of class I MHC in skeletal muscle fibers was an early and consistent feature of human inflammatory myopathies. Class I MHC staining in muscle fibers of myositis patients showed both cell surface and a reticular pattern of internal reactivity. The pathways of endoplasmic reticulum (ER) stress response, the unfolded protein response (glucose‐regulated protein 78 pathway), and the ER overload response (NF‐κB pathway) were significantly activated in muscle tissue of human myositis patients and in the mouse model. Ectopic expression of wild‐type mouse class I MHC (H‐2Kb) but not degradable glycosylation mutants of H‐2Kb induced ER stress response in C2C12 skeletal muscle cells.ConclusionThese results indicate that the ER stress response may be a major nonimmune mechanism responsible for skeletal muscle damage and dysfunction in autoimmune myositis. Strategies to interfere with this pathway may have therapeutic value in patients with this disease.
The effects of vitamin C supplementation on serum concentrations of uric acid: Results of a randomized controlled trial
Authors: Huang Han‐Yao , Appel Lawrence J. , Choi Michael J. , Gelber Allan C. , Charleston Jeanne , Norkus Edward P. , Miller Edgar R. 
Published: June 2005

AbstractObjectiveReductions in serum uric acid levels are clinically relevant. Previous studies have suggested a uricosuric effect of vitamin C. Whether vitamin C reduces serum uric acid is unknown. We undertook this study to determine the effects of vitamin C supplementation on serum uric acid concentrations.MethodsThe study was a double‐blinded placebo‐controlled randomized trial conducted in research units affiliated with an academic institution. Study participants were 184 nonsmokers, randomized to take either placebo or vitamin C supplements (500 mg/day) for 2 months.ResultsAt the end of the study period, serum uric acid levels were significantly reduced in the vitamin C group (mean change −0.5 mg/dl [95% confidence interval −0.6, −0.3]), but not in the placebo group (mean change 0.09 mg/dl [95% confidence interval −0.05, 0.2]) (P < 0.0001). The same pattern of results was evident in subgroups defined by age, sex, race, body mass index, chronic illness, diuretic use, and quartiles of baseline serum ascorbic acid levels. In the subgroups, from the lowest to the highest quartile of baseline serum uric acid, net mean changes (95% confidence intervals) in serum uric acid with vitamin C supplementation were −0.4 (−0.8, 0.01), −0.5 (−0.9, −0.2), −0.5 (−0.8, −0.2), and −1.0 (−1.6, −0.4) mg/dl (P = 0.06, 0.005, 0.003, and 0.002, respectively). Compared with placebo, vitamin C increased the estimated glomerular filtration rate.ConclusionSupplementation with 500 mg/day of vitamin C for 2 months reduces serum uric acid, suggesting that vitamin C might be beneficial in the prevention and management of gout and other urate‐related diseases.
Violation of the intent‐to‐treat principle and rate of missing data in superiority trials assessing structural outcomes in rheumatic diseases
Authors: Baron Gabriel , Boutron Isabelle , Giraudeau Bruno , Ravaud Philippe 
Published: June 2005

AbstractObjectiveTo evaluate the methodologic quality of and identify methodologic issues in superiority trials assessing structural outcomes in rheumatic diseases.MethodsWe searched Medline and the Cochrane Central Register of Controlled Trials for reports of randomized controlled trials assessing structural outcomes in osteoarthritis (OA), rheumatoid arthritis (RA), and osteoporosis (OP) published between January 1994 and December 2003 in high–impact factor general medical and specialty journals. One reader extracted data (quality assessment, intent‐to‐treat analysis [ITT analysis], rate of missing data, and methods of handling missing data), using a standardized form.ResultsA total of 81 reports were included in the analysis (37 on OP, 34 on RA, and 10 on OA). The mean ± SD methodologic quality scores on the Jadad scale (possible range 0–5) and the Delphi list (possible range 0–9) were 2.9 ± 1.2 and 6.4 ± 1.3, respectively. Although it was reported in 54 articles (66.7%) that the analysis was done on an ITT basis, full ITT analysis was performed in only 6 of the studies (7.4%), modified ITT analysis in 11 (13.6%), and case‐complete analysis in 48 (59.3%); the analysis was unclear in 16 articles (19.8%). The rate of missing data on structural outcomes could be determined in only 63 articles (77.8%) and was >20% in approximately one‐third of these reports. Methods for handling missing data on structural outcomes were described in 19 articles (23.5%) and were, in general, inappropriate.ConclusionLack of ITT analysis and a high rate of missing data in superiority trials assessing structural outcomes may bias results from such trials. Our recommendations for improving these shortcomings may help researchers plan, analyze, and report the results of such trials.
Efficient and scalable method for scaling up cell free protein synthesis in batch mode
Authors: Voloshin Alexei M. , Swartz James R. 
Published: June 2005

AbstractA novel method for general cell free system scale‐up in batch mode was applied to expression of E. coli chloramphenicol acetyl transferase (CAT) and a GMCSF‐scFv fusion protein being developed as a B‐cell lymphoma vaccine candidate (GLH). Performance of two different E. coli based cell‐free systems was evaluated using the new scale‐up approach. Reaction volumes from 15 to 500 µL were tested for both products and both reaction systems. In each case, the new scale‐up method preserved total, soluble, and active volumetric yields of GLH and CAT at every reaction volume. At the 500 µL reaction volume, the PANOx SP system produced 560 ± 36 µg/mL of active CAT and 99 ± 10 µg/mL of active GLH protein using the new thin film approach whereas 500 µL test tube reactions produced 250 ± 42 µg/mL and 72 ± 7 µg/mL of active CAT and GLH respectively. Similarly, 500 µL cell‐free synthesis reactions with the Cytomim system produced 481 ± 38 µg/mL of active CAT and 109 ± 15 µg/mL active GLH respectively in thin films compared to 29 ± 7 µg/mL of active CAT and 5 ± 2 µg/mL of active GLH protein in 500 µL test tube reactions. The new thin film approach improves oxygen supply for the Cytomim system, and increases the availability of hydrophobic surfaces. Analysis suggests that these surfaces provide significant benefit for protein expression and folding. We believe that this approach provides a general reaction scale‐up technology that will be suitable for any protein target, cell free system, and reaction volume. © 2005 Wiley Periodicals, Inc.
Process optimization of continuous gluconic acid fermentation by isolated yeast‐like strains of Aureobasidium pullulans
Authors: Anastassiadis Savas , Aivasidis Alexander , Wandrey Christian , Rehm Hans‐Jürgen 
Published: June 2005

AbstractThis study was focused on the optimization of a new fermentation process for continuous gluconic acid production by the isolated yeast‐like strain Aureobasidium pullulans DSM 7085 (isolate 70). Operational fermentation parameters were optimized in chemostat cultures, using a defined glucose medium. Different optima were found for growth and gluconic acid production for each set of operation parameters. Highest productivity was recorded at pH values between 6.5 and 7.0 and temperatures between 29 and 31°C. A gluconic acid concentration higher than 230 g/L was continuously produced at residence times of 12 h. A steady state extracellular gluconic acid concentration of 234 g/L was measured at pH 6.5. 122% air saturation yielded the highest volumetric productivity and product concentration. The biomass‐specific productivity increased steadily upon raising air saturation. An intracellular gluconic acid concentration of about 159 g/L (0.83 mol) was determined at 31°C. This is to be compared with an extracellular concentration of 223 g/L (1.16 mol), which indicates the possible existence of an active transport system for gluconic acid secretion, or the presence of extracellular glucose oxidizing enzymes. The new process provides significant advantages over the traditional discontinuous fungi operations. The process control becomes easier, thus offering stable product quality and quantity. © 2005 Wiley Periodicals, Inc.