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ID PMID Title PublicationDate abstract
16136625 Documented tuberculin skin testing among infliximab users following a multi-modal risk com 2006 Jan PURPOSE: Following its licensure, tuberculosis (TB) was reported as a potential adverse effect of infliximab. Subsequently, the product circular was changed to recommend tuberculin skin testing before patients received infliximab, which was reinforced by several risk communication efforts. The aim of this study was to evaluate patterns and predictors of documented tuberculin skin testing in patients before and after manufacturer, federal, and academic risk communications. METHODS: Patients administered infliximab were identified from 11 health plans located throughout the United States, and claims data were examined to determine whether the patients had received a tuberculin skin test. Patients were divided into three cohorts depending on the timing of their first infliximab treatment in relation to the risk communication efforts. RESULTS: The overall tuberculin skin testing rate doubled from 15.4% in the first cohort to 30.9% in the last cohort, while the rate of pre-infliximab treatment testing increased from 0 to 27.7% (Chi-squared test for trend, p < 0.0001 for both). Tuberculin skin testing rates were significantly higher in women, those with a diagnosis of rheumatoid or psoriatic arthritis, and those with a rheumatologist as prescriber. After multivariable analysis, only rheumatologist remained significantly associated with tuberculin skin testing. CONCLUSIONS: Although the tuberculin skin testing rate was relatively low overall, tuberculin skin testing doubled over 30 months of ongoing risk communication efforts and under ascertainment likely occurred. We also found variation in the tuberculin skin testing rate associated with physician specialty. This study demonstrates a significant change in patient care following risk communication efforts.
17185325 Decreased B cell activating factor receptor expression on peripheral lymphocytes associate 2007 Jun OBJECTIVE: To analyse B cell activating factor (BAFF) receptor (BAFF-R) expression on peripheral lymphocytes from patients with primary Sjögren's syndrome (pSS) and systemic lupus erythematosus (SLE). PATIENTS AND METHODS: Peripheral blood mononuclear cells from 20 patients with pSS, 19 patients with SLE and 15 controls were examined by flow cytometry to investigate BAFF-R mean fluorescence intensity (MFI) on lymphocytes. BAFF-R mRNA level from isolated blood B cells of nine patients with pSS and eight controls was assessed by real-time quantitative reverse transcription-PCR. BAFF serum level was determined by ELISA. RESULTS: In all subjects, BAFF-R was expressed on all naïve CD27- and memory CD27+ B-cells and was present on <0.5% of T cells. The expression of BAFF-R on B cells was significantly decreased in patients with pSS as compared with controls (MFI = 7.8 vs 10.6, p = 0.001), and was intermediate in patients with SLE (MFI = 9.5). Serum BAFF level was inversely correlated with BAFF-R MFI (p = 0.007), but not because of competition between endogenous BAFF (at observed concentrations in patients) and the monoclonal antibody (11C1) detecting BAFF-R. BAFF-R mRNA levels did not differ between patients with pSS and controls (p = 0.48). BAFF-R MFI decreased after overnight culture with recombinant human BAFF (from 32.5 to 25.4, p = 0.03). Contrary to the serum BAFF level, BAFF-R expression was correlated with extraglandular involvement in pSS and SLE Disease Activity Index. CONCLUSIONS: BAFF-R expression is reduced on peripheral B cells of patients with pSS and SLE. This down-regulation occurs through a post-transcriptional mechanism and could be the consequence of chronic increase in BAFF. BAFF-R levels on B cells could be a novel activity biomarker in autoimmune diseases.
16287915 Ex vivo CD(+) T-cell cytokine expression from patients with Sjögren's syndrome following 2006 Apr OBJECTIVE: To assess ex vivo CD4(+) T-cell cytokine expression from patients with primary Sjögren's syndrome (SS) following in vitro stimulation to induce proliferation, as proliferation is closely related to differentiation of cytokine-producing cells. METHODS: Peripheral blood mononuclear cells (PBMCs) separated from primary SS patients (n = 28) and controls (n = 25) were analysed. PBMCs were stimulated with concanavalin A followed by phorbol 12-myristate 13-acetate and ionomycin. Intracellular interferon-gamma (IFN-gamma) and interleukin-4 (IL)-4 in proliferating CD4(+) T cells were assessed by flow cytometry. The proportion of cytokine-producing cells and proliferating cells in each division cycle was assessed using [5(and 6)-carboxyfluorescein diacetate, succinimidyl ester]-labelled CD4(+/-) T cells. RESULTS: The proportion of IFN-gamma+ proliferating CD4(+) T cells in each cell division cycle from extraglandular SS was increased in glandular SS patients compared glandular SS patients with controls (P<0.05 approximately 0.01). The percentage of IFN-gamma single positive proliferating CD4(+) T cells was greater in extraglandular SS patients (26.7+/-14.1%) compared with glandular SS (9.9 +/- 9.1%) (P<0.01) and controls (9.4 +/- 5.8%) (P<0.001). There was no significant difference in the percentages of IL-4(+) proliferating CD4(+) T cells among the groups. However, the proliferating response of CD4(+) T cells was significantly decreased in extraglandular SS patients (percentage of proliferating cells 38.4 +/- 18.6%) compared with that in glandular SS patients (64.2 +/- 17.2%) (P<0.05) and controls (63.1+/-10.6%) (P<0.01). CONCLUSIONS: CD4(+) T cells from extraglandular SS patients may have a predisposition for entry into the IFN-gamma-producing effector pathway as a result of the stimulations. These results are helpful for understanding the immunological difference between glandular and extraglandular SS and the mechanisms of disease progression.
16255056 Increased expression of the novel proinflammatory cytokine high mobility group box chromos 2005 Nov OBJECTIVE: To investigate the role of the novel cytokine high mobility group box chromosomal protein 1 (HMGB-1) in the pathogenesis of cutaneous lupus erythematosus (CLE). METHODS: Punch biopsy specimens of lesional and unaffected skin from 10 patients with CLE and 3 healthy control subjects were investigated. Immunohistochemical staining for HMGB-1, tumor necrosis factor alpha (TNFalpha), and interleukin-1beta (IL-1beta) was performed on consecutive sections. Analysis of single-nucleotide polymorphisms of -308 TNF was performed on DNA extracted from peripheral blood mononuclear cells. RESULTS: An altered expression of HMGB-1 was observed both in the epidermis and in the dermal infiltrates of lesional skin. Expression of HMGB-1 in the epidermis and dermis was increased (P < 0.01 and P < 0.001, respectively, versus unaffected skin), and translocation to the cytoplasm as well as the extracellular presence of secreted HMGB-1 were found. Increased levels of TNFalpha and IL-1beta were also observed in the dermal infiltrates of lesional skin (P < 0.01 and P < 0.05, respectively, versus unaffected skin). The carrier frequency of the -308A TNF polymorphism was 80% in patients with subacute CLE, but this was not related to higher expression of TNFalpha in biopsy specimens from the CLE group. CONCLUSION: The high amount of extracellular HMGB-1 observed in skin lesions indicates that HMGB-1 is involved in the inflammatory process of CLE. TNFalpha and IL-1beta may form a proinflammatory loop with HMGB-1, since they can induce the release of each other. The extracellular HMGB-1 observed by immunostaining of the epidermis indicates that keratinocytes may be an as yet unrecognized source of secreted HMGB-1, underscoring the role of the target organ in the rheumatoid autoimmune inflammatory process.
16996813 Eosinophil chemotactic factor-L (ECF-L) enhances osteoclast formation by increasing in ost 2007 Feb ECF-L is a novel autocrine stimulator of osteoclast (OCL) formation that enhances the effects of 1,25-(OH)2D3 and RANK ligand (RANKL) and is increased in inflammatory conditions such as rheumatoid arthritis. ECF-L acts at the later stages of OCL formation and does not increase RANKL expression. Thus, its mechanism of action is unclear. Therefore, RAW 264.7 cells and M-CSF-dependent murine bone marrow macrophage (MDBM) cells were treated with RANKL and/or with recombinant ECF-L expressed as a Fc fusion protein (ECF-L-Fc) to determine their effects on NF-kappaB, AP-1 and JNK activity, and on the expression of the adhesion molecules that have been implicated in OCL formation. These parameters were measured by semiquantitative and PCR and Western blot analysis. In addition, the role of ICAM-1 was further assessed by treating normal mouse marrow cultures with ECF-L-Fc and 10(-10) M 1,25-(OH)2D3 in the presence or absence of a blocking ICAM-1 antibody or treating marrow cultures from ICAM-1 knockout mice with ECF-L and 1,25-(OH)2D3. ECF-L-Fc by itself only modestly increased NF-kappaB binding and JNK activity in RAW 264.7 cells, which was further enhanced by RANKL. In contrast, ECF-L-Fc increased LFA-1alpha and ICAM-1 mRNA levels 1.8-fold in mouse marrow cultures, and anti-ICAM-1 almost completely inhibited OCL formation induced by 10(-10) M 1,25-(OH)2D3 and ECF-L. Furthermore, ECF-L did not increase OCL formation in marrow cultures from ICAM-1 knockout mice. Taken together, these results demonstrate that ECF-L enhances RANKL and 1,25-(OH)2D3-induced OCL formation by increasing adhesive interactions between OCL precursors through increased expression of ICAM-1 and LFA-1.
16707469 Histone deacetylase inhibitors suppress the inducibility of nuclear factor-kappaB by tumor 2006 May 15 Recently, the inhibition of histone deacetylase (HDAC) enzymes has attracted attention in the oncologic community as a new therapeutic opportunity for hematologic and solid tumors including non-small cell lung cancer (NSCLC). In hematologic malignancies, such as diffuse large B-cell lymphoma, the HDAC inhibitor (HDI), suberoylanilide hydroxamic acid (SAHA), has recently entered phase II and III clinical trials. To further advance our understanding of their action on tumor cells, we investigated the possible effect of HDI treatment on the functionality of the nuclear factor-kappaB (NF-kappaB) pathway in NSCLC. We found that in the NSCLC cell lines, A549 and NCI-H460, the NF-kappaB pathway was strongly inducible, for example, by stimulation with tumor necrosis factor-alpha (TNF-alpha). Incubation of several NSCLC cell lines with HDIs resulted in greatly reduced gene expression of TNF-alpha receptor-1. HDI-treated A549 and NCI-H460 cells down-regulated TNF-alpha receptor-1 mRNA and protein levels as well as surface exposure, and consequently responded to TNF-alpha treatment with reduced IKK phosphorylation and activation, delayed IkappaB-alpha phosphorylation, and attenuated NF-kappaB nuclear translocation and DNA binding. Accordingly, stimulation of NF-kappaB target gene expression by TNF-alpha was strongly decreased. In addition, we observed that SAHA displayed antitumor efficacy in vivo against A549 xenografts grown on nude mice. HDIs, therefore, might beneficially contribute to tumor treatment, possibly by reducing the responsiveness of tumor cells to the TNF-alpha-mediated activation of the NF-kappaB pathway. These findings also hint at a possible use of HDIs in inflammatory diseases, which are associated with the overproduction of TNF-alpha, such as rheumatoid arthritis or Crohn's disease.
15771433 Synthesis and discovery of pyrazine-pyridine biheteroaryl as a novel series of potent vasc 2005 Mar 24 Pathological angiogenesis is associated with disease states such as cancer, diabetic retinopathy, rheumatoid arthritis, endometriosis, and psoriasis. There is much evidence that direct inhibition of the kinase activity of vascular endothelial growth factor receptor-2 (VEGFR-2) will result in the reduction of angiogenesis and the suppression of tumor growth. Attempts to optimize a cyclin-dependent kinase-1 (CDK1) inhibitor by using palladium-catalyzed C-C bond, C-N bond formation reactions to assemble diverse biheteroaryl molecules led to the unexpected discovery of a pyrazine-pyridine biheteroaryl as a novel series of potent VEGFR-2 inhibitors. Compound 15, which had IC(50) = 0.084 microM at VEGFR-2, showed very modest selectivity against fibroblast growth factor receptor-2 (IC(50) = 0.21 microM), platelet-derived growth factor receptor (IC(50) = 0.36 microM), and glycogen synthase kinase-3 (IC(50) = 0.478 microM), while it exhibited more than 10-fold selectivity against epidermal growth factor receptor (IC(50) = 1.36 microM) and insulin-R kinase (IC(50) = 1.69 microM). On the other hand, compound 15 exhibited more than 100-fold selectivity against calmodulin kinase 2; casein kinase-1 and -2; CDK1 and -4; mitogen-activated protein kinase; and protein kinase A, Cbeta2, and Cgamma (IC(50) >10 microM). Compound 15 also displayed high inhibitory potency on VEGF-stimulated human umbilical vein endothelial cell (HUVEC) proliferation (IC(50) = 0.005 microM) and good selectivity against cell lines such as HUVEC, human aortic smooth muscle cells, and MRC5 lung fibroblasts. Molecular docking studies were conducted in an attempt to rationalize the unexpected high VEGFR-2 selectivity of 15.
16452391 A novel spleen tyrosine kinase inhibitor blocks c-Jun N-terminal kinase-mediated gene expr 2006 May Spleen tyrosine kinase (Syk) is a key regulator of cell signaling induced by cytokines or Fc receptor engagement. However, the role of Syk in rheumatoid arthritis (RA) is not known yet. We investigated the pathways activated by Syk in tumor necrosis factor-alpha (TNFalpha)-stimulated fibroblast-like synoviocytes (FLS) using the novel Syk inhibitor N4-(2,2-dimethyl-3-oxo-4H-pyrid[1,4]oxazin-6-yl)-5-fluoro-N2-(3,4,5-trimethoxyphenyl)-2,4-pyrimidinediamine (R406). Using immunohistochemistry, Syk was detected in RA synovial tissue (ST), primarily in the synovial intimal lining. Western blot analysis demonstrated significantly greater amounts of phospho-Syk expression in RA ST compared with osteoarthritis ST. The kinase was expressed and functionally activated by TNFalpha in FLS and was blocked by R406. Western blot analysis demonstrated that Syk inhibition by R406 markedly suppressed TNFalpha-induced c-Jun N-terminal kinase (JNK) phosphorylation in FLS, with a modest decrease in extracellular signal-regulated kinase phosphorylation. Surprisingly, p38 activation was not affected by R406. The Syk inhibitor also decreased TNFalpha-induced mitogen-activated protein kinase kinase (MKK) 4 phosphorylation but not MKK3 and MKK6 phosphorylation, which is consistent with its selective sparing of p38. The connection between Syk and JNK was confirmed by demonstrating decreased phospho-c-Jun protein expression and complete inhibition of JNK function in R406-treated cells. R406 also suppressed downstream actions of JNK, as determined by activator protein 1 binding, as well as matrix metalloproteinase 3 gene expression. These data demonstrate that Syk activation plays an essential role in TNFalpha-induced cytokine and matrix metalloproteinase production in RA FLS, especially by suppressing activation of the JNK pathway.
16194439 [Surgical treatment for disorders of the cervicothoracic junction region]. 2005 PURPOSE OF THE STUDY: The complex anatomy of the cervicothoracic junction region makes a reliable assessment of plain radiographs in lateral projection difficult or even impossible, which may result in failure to detect fracture or other pathology in this region of the spine. The aim of this study was to evaluate the patients with spinal disorders in the region of the seventh cervical to the third thoracic vertebrae treated at our department. MATERIAL: During the period from November 2001 to June 2004, 34 patients with disorders of the C7-T3 region were treated surgically at the Department of Spinal Surgery, Motol Teaching Hospital, which accounted for 2.1% of the 1537 patients treated for spinal diseases in this period. Instability of the cervicothoracic junction was caused by tumors in 15 and by injury in 14 patients. Other diagnoses included deformity associated with rheumatoid arthritis (RA) in two patients, spondylodiscitis in one, and hemivertebral deformity at C7 and T1, each in one patient. The group included 16 women and 18 men between 8 and 75 years, with the mean of 52.3 years (after excluding the two children with hemivertebral deformity aged 8 and 9 years, respectively). The trauma subgroup had a significantly lower mean age (43.6 years) than the tumor subgroup (59.9 years). METHODS: We placed the patients in three groups according to the etiology of cervicothoracic junction disorder, namely, 1. tumors and spondylodiscitis; 2. injuries; 3. others. Group 1 included 16 patients, 15 with tumors and one with spondylodiscitis. Two patients were treated by dorsal stabilization, one by ventral stabilization and the rest underwent combined surgery. Of 14 patients in group 2, three were treated from the posterior approach, six from the anterior approach and five by the combined approach. All group 3 patients underwent surgery from the posterior approach, with two patients being treated without instrumentation. RESULTS: Of the 34 patients, only 33 were included; one was lost to follow-up soon after the operation. In group 1, no excellent, five very good, five satisfactory and two unsatisfactory outcomes were recorded. No intraoperative complications such as injury to the major vessels or nerve structures occurred; in one patient, profuse bleeding from arteries supplying a metastatic tumor had to be arrested. Late complications included loosening of the dorsal instrumentation in two patients, who required repeat operations. In group 2, there were six excellent, four good, two satisfactory and one poor outcomes. Late complications in one patient included loosening of the ventral instrumentation, followed by repeat surgery. Group 3 showed two excellent and two satisfactory outcomes; the latter were in the RA patients. Late complications involved one loosening of the dorsal instrumentation requiring repeat surgery. No injury to the major vessels or nerve structures was recorded in either group 2 or group 3. No deep infection was recorded in any of the three groups. DISCUSSION: The results of our evaluation are in agreement with those of other authors and, similarly to them, we had to deal with the difficult issues of diagnosis. Currently, we prefer, in addition to conventional X-ray examination, CT scans including sagittal and frontal reconstruction, recently completed with magnetic resonance imaging, in all patients with cervicothoracic junction disorders. This policy allows us to avoid delays in making correct diagnosis and to provide conditions for effective treatment. In stabilization from the posterior approach we use rod-screw fixation that, in the majority of cases, is not combined with thoracic fixation. Previously, we have inserted screws in the articular processes at the C7 level, but now we prefer transpedicular fixation. Complicated anterior surgical procedures, such as complete or partial sternotomy, are always performed with the assistance of a thoracic surgeon. A noticeably high number of patients with neurological deficit was seen also in our group. Postoperative care is always provided in cooperation with the spinal unit of our hospital. Intensive inter-disciplinary cooperation has an important role in that our patients have a minimum of complications in comparison with the literature data. CONCLUSIONS: Injuries and diseases of the spine at the cervicothoracic junction present a complex issue with a high potential for mistakes and complications. The principle of success lies in a high-quality X-ray examination, CT scans with sagittal and frontal reconstruction, and magnetic resonance imaging of the region affected. The complex anatomy of that region requires demanding surgical procedures, which can be performed only by a highly qualified and specialized team with appropriate facilities.
15813652 Cyclo-oxygenase-2 inhibitors: when should they be used in the elderly? 2005 Chronic pain in the elderly is frequently a result of arthritic disorders, particularly osteoarthritis. The cyclo-oxygenase (COX)-2 inhibitors are as effective as standard NSAIDs for the relief of pain and for improving function in elderly patients with osteoarthritis and rheumatoid arthritis. COX-2 inhibitors increase the risk of serious gastroduodenal adverse reactions but there is evidence that they carry a lower risk for these adverse effects than standard NSAIDs, except when there is concurrent aspirin use. Since gastroduodenal disorders are the most frequently reported serious adverse effects of NSAIDs and these disorders occur more frequently in the elderly, COX-2 inhibitors offer an alternative to standard NSAIDs in this age group. However, they are not appropriate for many patients with cardiovascular and renal disease. The adverse reaction profile of the COX-2 inhibitors has confirmed the role of the COX-2 enzyme in renal function, salt and water homeostasis and the vascular endothelium. Thus, like standard NSAIDs, COX-2 inhibitors can cause renal failure, hypertension and exacerbation of cardiac failure. Of note is that these disorders are dose related. Thus, there are good reasons to avoid high doses of COX-2 inhibitors in the elderly. Clinical trials indicate that daily doses of rofecoxib 12.5 mg, celecoxib 100-200 mg, valdecoxib 10mg and etoricoxib 60 mg are the minimum effective doses of these agents. Data from the New Zealand Intensive Medicines Monitoring Programme indicate that celecoxib 200 mg/day and rofecoxib 25 mg/day are/were the most commonly prescribed doses and that 6% of patients had taken rofecoxib 50 mg/day for longer than recommended. Recent research indicates that COX-2 inhibitors have a thrombotic potential, especially in high doses and when use is prolonged, and this further limits the extent to which they can be used in the elderly. Important interactions with COX-2 inhibitors in the elderly include those with warfarin, which can result in loss of control of anticoagulation, and those with ACE inhibitors, angiotensin II type 1 receptor antagonists and diuretics, which can result in loss of control of blood pressure and cardiac failure and, in hypovolaemic conditions, renal failure. The clinical significance of an interaction between celecoxib and aspirin to reduce the antiplatelet effect of the latter drug is unknown. Preliminary information from spontaneous reporting systems indicates that there may be differences in the risk of cardiac failure and hypertension between standard NSAIDs and COX-2 inhibitors and between rofecoxib and celecoxib. More formal studies using equivalent doses are needed to test this observation. Use of COX-2 inhibitors may be considered in the elderly to reduce the risk of gastroduodenal complications associated with standard NSAIDs but only when consideration has first been given to use of less toxic medicines as alternatives or supplements, the appropriate dose of the COX-2 inhibitor or standard NSAID, the presence and possible impact of co-morbidities, and the implications of taking COX-2 inhibitors with any concomitant medications. Equally important is regular monitoring of the patient taking a COX-2 inhibitor for efficacy and adverse effects, and ensuring that the patient has a continuing need to keep taking the drug. Close attention also needs to be paid to intercurrent illnesses and new prescriptions that may reduce the safety of the COX-2 inhibitor. A standard NSAID plus a proton pump inhibitor may be equally effective as a COX-2 inhibitor in reducing the risk of gastroduodenal toxicity and if used the same prescribing advice applies. Current knowledge concerning the thrombotic potential of COX-2 inhibitors suggests that this combination, if tolerated, may be preferable to a COX-2 inhibitor, particularly where prolonged use is required. This knowledge also indicates that for patients with or at high risk of ischaemic heart disease or stroke, COX-2 inhibitors are contraindicated.
15701708 AGIX-4207 [2-[4-[[1-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1-methylethyl]thio] 2005 May The pathogenesis of chronic inflammatory diseases, including rheumatoid arthritis, is regulated, at least in part, by modulation of oxidation-reduction (redox) homeostasis and the expression of redox-sensitive inflammatory genes including adhesion molecules, chemokines, and cytokines. AGIX-4207 [2-[4-[[1-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1-methylethyl]thio]-2,6-bis(1,1-dimethylethyl)phenoxy]acetic acid] is a novel, orally active, phenolic antioxidant and anti-inflammatory compound with antirheumatic properties. To elucidate its anti-inflammatory mechanisms, we evaluated AGIX-4207 for a variety of cellular, biochemical, and molecular properties. AGIX-4207 exhibited potent antioxidant activity toward lipid peroxides in vitro and displayed enhanced cellular uptake relative to a structurally related drug, probucol. This resulted in potent inhibition of cellular levels of reactive oxygen species in multiple cell types. AGIX-4207 selectively inhibited tumor necrosis factor (TNF)-alpha-inducible levels of the redox-sensitive genes, vascular cell adhesion molecule-1 and monocyte chemoattractant protein-1, with less inhibition of E-selectin, and no effect on intracellular adhesion molecule-1 expression in endothelial cells. In addition, AGIX-4207 inhibited cytokine-induced levels of monocyte chemoattractant protein-1, interleukin (IL)-6, and IL-8 from endothelial cells and human fibroblast-like synoviocytes as well as lipopolysaccharide-induced release of TNF-alpha, IL-1beta, and IL-6 from human peripheral blood mononuclear cells. AGIX-4207 did not inhibit TNF-alpha-induced nuclear translocation of nuclear factor of the kappa-enhancer in B cells (NF-kappaB), suggesting that the mechanism of action is independent of this redox-sensitive transcription factor. Taken together, these results provide a mechanistic framework for understanding the anti-inflammatory and antirheumatic activity of AGIX-4207 and provide further support for the view that inhibition of redox-sensitive inflammatory gene expression is an attractive approach for the treatment of chronic inflammatory diseases.
16046111 MKK3/6-p38 MAPK negatively regulates murine MMP-13 gene expression induced by IL-1beta and 2005 Oct Matrix metalloprotease-13 (MMP-13) or collagenase-3 is involved in a number of pathologic processes such as tumor metastasis and angiogenesis, osteoarthritis, rheumatoid arthritis and periodontal diseases. These conditions are associated with extensive degradation of both connective tissue and bone. This report examines gene regulation mechanisms and signal transduction pathways involved in Mmp-13 expression induced by proinflammatory cytokines in periodontal ligament (PDL) fibroblasts. Mmp-13 mRNA expression was increased 10.7 and 9.5 fold after stimulation with IL-1beta (5 ng/mL) and TNF-alpha (10 ng/mL), respectively. However, inhibition of p38 MAPKinase with SB203580 resulted in significant (p<0.001) induction (23.2 and 18.1 fold, respectively) of Mmp-13 mRNA as assessed by real time PCR. Negative regulation of IL-1beta induced Mmp-13 expression was confirmed by inhibiting p38 MAPK gene expression with siRNA. Transient transfection of dominant negative forms of MKK3 and MKK6 also resulted in increased levels of Mmp-13 mRNA after IL-1beta stimulation. Mmp-13 mRNA expression induced by TNF-alpha was decreased by JNK and ERK inhibition. Western blot and zymogram analysis indicated that Mmp-13 protein expression induced by the proinflammatory cytokines were also upregulated by inhibition of p38 MAPK. Reporter gene experiments using stable cell lines harboring 660-bp sequence of the murine Mmp-13 proximal promoter indicated that transcriptional mechanisms were at least partially involved in this negative regulation of Mmp-13 expression by p38 MAPK and upstream MKK3/6. These results suggest a negative transcriptional regulatory mechanism mediated by p38 MAPK and upstream MKK3/6 on Mmp-13 expression induced by proinflammatory cytokines in PDL fibroblasts.
30000400 Methotrexate. 2006 Most sources consider breastfeeding to be contraindicated during maternal high-dose antineoplastic drug therapy with methotrexate. An abstinence period of at least 1 week after chemotherapy doses of methotrexate has been suggested.[1] Chemotherapy may adversely affect the normal microbiome and chemical makeup of breastmilk.[2] Women who receive chemotherapy during pregnancy are more likely to have difficulty nursing their infant.[3] Maternal doses of methotrexate up to 92 mg (1.12 mg/kg) produce low levels in milk, leading some authors to state that low single or weekly doses, such as those used for ectopic pregnancy or rheumatoid arthritis, are of low risk to the breastfed infant,[4-8] although some expert opinion warns against this use.[9-13] Withholding breastfeeding for 24 hours after a weekly low dose of methotrexate may decrease the infant's dose by 40%.[14-16] If breastfeeding during long-term, low-dose methotrexate use is undertaken, monitoring of the infant's complete blood count and differential could be considered.
16206346 Etanercept exerts beneficial effects on articular cartilage biomarkers of degradation and 2005 Oct OBJECTIVE: Anti-tumor necrosis factor-alpha (TNF-alpha) therapies are not only beneficial for reducing symptoms in rheumatoid arthritis (RA) but also for structural damage visible on plain radiographs and serological biomarkers of articular cartilage damage. It is not known if these therapies also prevent structural damage in ankylosing spondylitis (AS). The low sensitivity to change over time of plain radiographic instruments mandates a search for the effects of these therapies on possible biomarkers of cartilage damage. METHODS: We studied 2 populations of patients with AS: (1) patients recruited to a placebo controlled trial of etanercept in AS for 16 weeks; (2) an observational cohort receiving infliximab for disease refractory to conventional therapy. Clinical (morning stiffness, nocturnal pain, Bath AS Disease Activity Index) and laboratory [erythrocyte sedimentation rate (ESR), C-reactive protein (CRP)] assessments of disease activity were performed at baseline and at either 16 weeks (clinical trial cohort) or at 14 weeks (observational cohort). We measured serum matrix metalloproteinase-1 (MMP-1), MMP-3, human cartilage glycoprotein-39 (YKL-40), and cartilage oligomeric matrix protein by ELISA at the same timepoints. We also measured serum concentrations of 2 novel biomarker epitopes, C2C and 846, by competitive ELISA. The C2C assay detects a neoepitope at the carboxy terminus of the long three-quarter amino-terminal fragment generated following cleavage of type II collagen by collagenases. Aggrecan 846 epitope is a chondroitin sulfate epitope present on intact aggrecan molecules. Both these assays would detect products originating from both hyaline cartilages and intervertebral discs. RESULTS: There was a significant reduction in levels of C2C (p = 0.005) and a significant increase in the 846 epitope (p = 0.01) in patients who received etanercept compared to placebo controls. Changes in C2C correlated significantly with changes in ESR (r = 0.51, p = 0.04) and CRP (r = 0.48, p = 0.048). Significant changes in C2C were not evident in the infliximab observational cohort, although significant reductions were noted in levels of MMP-3 (p = 0.04) and MMP-1 (p = 0.02) at 14 weeks that were not observed in the etanercept group. Analysis of all baseline samples showed a significant correlation between levels of MMP-3 with CRP (r = 0.73, p < 0.0001), and YKL-40 (r = 0.71, p < 0.0001). No correlation was evident at baseline between levels of C2C or 846 epitope and either acute phase reactants or other biomarkers. CONCLUSION: Our data suggest that an anti-TNF-alpha agent, etanercept, may modify cartilage turnover. These include decreased degradation of type II collagen and increased turnover of aggrecan. Additional therapeutic properties of some anti-TNF-alpha agents in AS, such as infliximab, may be related to decreased expression of MMP. Additional studies in larger populations are therefore warranted.
16320341 Exposure and binding of selected immunodominant La/SSB epitopes on human apoptotic cells. 2005 Dec OBJECTIVE: Opsonization of apoptotic cells by autoantibodies bound to surface membrane-translocated La/SSB antigens may initiate tissue damage in the setting of congenital heart block. By injecting pregnant mice with human anti-La antibodies, we previously demonstrated the formation of IgG-apoptotic cell complexes in the developing mouse fetus; however, the binding of anti-La antibodies to human-specific epitopes could not be addressed. Accordingly, the objective of the current study was to delineate the epitope specificity of human La antibodies that are exposed on the surface of apoptotic cells. METHODS: We used fluorescence microscopy and flow cytometry to assess the binding of human anti-La antibodies affinity purified against immunodominant epitopes of La to human cells undergoing spontaneous apoptosis, in a murine xenograft model in vivo and in cultured human fetal cardiocytes rendered apoptotic in vitro, respectively. RESULTS: Anti-La antibodies bound to immunodominant epitopes of La within the NH(2)-terminus and the RNA recognition motif (RRM) region of apoptotic human cells, in both xenografts and fetal cardiocytes. In contrast, human antibodies affinity purified against the COOH-terminal La epitope did not bind apoptotic cells in either model. This defines the topology of redistributed La during apoptosis, with surface exposure of the NH(2)-terminus and RRM regions. The potential importance of anti-La NH(2)-terminal and anti-La RRM specificity was confirmed by detection of this reactivity in mothers of children with congenital heart block. CONCLUSION: These findings provide insight into both the molecular modification of the La autoantigen during apoptosis and the specificity of antibodies capable of binding to surface-exposed La. Subsequent formation of surface immune complexes may lead to tissue injury in patients with autoimmune diseases such as congenital heart block.
16207350 Primary and secondary autoimmune neutropenia. 2005 Antineutrophil antibodies are well recognized causes of neutropenia, producing both quantitative and qualitative defects in neutrophils and increased risk for infection. In primary autoimmune neutropenia (AIN) of infancy, a moderate to severe neutropenia is the sole abnormality; it is rarely associated with serious infections and exhibits a self-limited course. Chronic idiopathic neutropenia of adults is characterized by occurrence in late childhood or adulthood, greater prevalence among females than among males, and rare spontaneous remission. Secondary AIN is more commonly seen in adults and underlying causes include collagen disorders, drugs, viruses and lymphoproliferative disorders. In most patients with AIN, antibodies recognize antigens located on the IgG Fc receptor type 3b but other target antigens have been recently identified in secondary AIN. Granulocyte colony-stimulating factor is a proven treatment in patients with AIN of all types and is now preferred to other possible therapies.
16530759 Molecular mechanisms of lacrimal acinar secretory vesicle exocytosis. 2006 Jul The acinar epithelial cells of the lacrimal gland are responsible for the production, packaging and regulated exocytosis of tear proteins into ocular surface fluid. This review summarizes new findings on the mechanisms of exocytosis in these cells. Participating proteins are discussed within the context of different categories of trafficking effectors including targeting and specificity factors (rabs, SNAREs) and transport factors (microtubules, actin filaments and motor proteins). Recent information describing fundamental changes in basic exocytotic mechanisms in the NOD mouse, an animal model of Sjögren's syndrome, is presented.
16079392 Inhibition of cystine uptake disrupts the growth of primary brain tumors. 2005 Aug 3 Glial cells play an important role in sequestering neuronally released glutamate via Na+-dependent transporters. Surprisingly, these transporters are not operational in glial-derived tumors (gliomas). Instead, gliomas release glutamate, causing excitotoxic death of neurons in the vicinity of the tumor. We now show that glutamate release from glioma cells is an obligatory by-product of cellular cystine uptake via system xc-, an electroneutral cystine-glutamate exchanger. Cystine is an essential precursor for the biosynthesis of glutathione, a major redox regulatory molecule that protects cells from endogenously produced reactive oxygen species (ROS). Glioma cells, but not neurons or astrocytes, rely primarily on cystine uptake via system xc- for their glutathione synthesis. Inhibition of system xc- causes a rapid depletion of glutathione, and the resulting loss of ROS defense causes caspase-mediated apoptosis. Glioma cells can be rescued if glutathione status is experimentally restored or if glutathione is substituted by alternate cellular antioxidants, confirming that ROS are indeed mediators of cell death. We describe two potent drugs that permit pharmacological inhibition of system xc-. One of these drugs, sulfasalazine, is clinically used to treat inflammatory bowel disease and rheumatoid arthritis. Sulfasalazine was able to reduce glutathione levels in tumor tissue and slow tumor growth in vivo in a commonly used intracranial xenograft animal model for human gliomas when administered by intraperitoneal injection. These data suggest that inhibition of cystine uptake into glioma cells through the pharmacological inhibition of system xc- may be a viable therapeutic strategy with a Food and Drug Administration-approved drug already in hand.
15860146 [Our experience with revision total knee arthroplasty]. 2005 PURPOSE OF THE STUDY: In the period from 1990 and June 2003, 885 total knee replacements were performed at the orthopedic ward of the Ceske Budejovice Hospital. Of these, 19 (2.14 %) patients underwent revision surgery; in addition, 25 patients who had had primary surgery in other hospitals were operated on. Of these 44 patients, 25 were followed up and evaluated. The aim of the study was to evaluate the pre-operative treatment including examination for bacterial infection by cultivation, the selection of an optimal procedure (one- or two-stage operation, surgical approach and implantation technique) and postoperative therapy. MATERIAL: The 25 evaluated patients were followed up for an average of 34.5 months (range, 6-109 months) after reimplantation. Loosening occurred in most of the commonly used types of primary implants. The group comprised five men and 19 women; the average age at the time of reoperation was 70 years (range, 51-78 years). Ten patients had repeat surgery on the left and 14 on the right knee at an average of 43.5 months (range, 4-120 months) after primary surgery. Fourteen patients were treated by one-stage and 10 patients by two-stage surgery. The Genesis system (Smith Nephew) was used in 13 patients, Sigma PFC revision implant (Johnson and Johnson) in eight, Walter-Motorlet implant (reuse of the primary implant at the time when a revision system was not available) in one and external fixator in five patients. METHODS: Revision arthroplasty was indicated on the basis of clinical symptoms and X-ray, scintigraphic and biochemical (CRP, WBC, FW) examinations. The use of recently adopted methods (procalcitonin, orosomucoid, alpha-1-antitrypsin, beta-2- macroglobulin, ceruloplasmin, PCR and PET) was not evaluated because of short-term applications. Patients in whom infection or colonization of the implant was suspected were treated by two-stage reimplantation, using a canalized spacer with a stem and a patellar pelota made of antibiotic-loaded cement. The average time between implant removal and reimplantation was 108 days (range, 60-244 days). Each removed implant was placed in a culture medium for 5 to 7 days. This resulted in a high occurrence of positive cultivation results even in the patients who, on the basis of previous examination, were first considered to have had aseptic loosening and had undergone one-stage surgery. All patients with positive tests received long-term antibiotic therapy, usually a combination of ciprofloxacin and rifampicin, according to the cultivation results. RESULTS: Out of 14 one-stage reimplantations (indicated for by the negative results of all laboratory examinations), implant colonization was recorded in five cases, with a coagulase-negative staphylococcus being the most frequent infectious agent. No recurrent infection was found after the long-term antibiotic course. One patient with the implant infected with Staphylococcus aureus underwent primary arthrodesis. Out of 10 two-stage reimplantations (in patients with positive laboratory tests), recurrent infection was found in two cases and was caused by a pathogen different from the original one. The patients were treated by arthrodesis. Good outcomes, defined as a functional total knee replacement free from infection at least 6 months after reimplantation, were achieved in 79 % of the patients. Better functional results were obtained by onestage surgery. Patients with concomitant rheumatoid arthritis had aseptic loosening more frequently, and patients with impaired immunological status, due to diabetes mellitus, cytostatic drug or corticosteroid administration, more often showed septic loosening. DISCUSSION: The 2.14 % loosening of total knee arthroplasty in our patients (19 out of 885) can be considered a good result. A functional joint was achieved in all patients (100 %) with aseptic loosening and in 69 % of those with infected or colonized implants. The results of routine biochemical tests and bacteriological cultivation did not allow us to distinguish aseptic from septic loosening with certainty. Therefore, we adopted new screening markers (PCR and PET) and a new method of microbiological examination of the removed implant and collected tissue. However, we could evaluate the role of these specialized tests only on the basis of literature data, since we had only short-term experience with them ourselves. Our results with the treatment of early loosening of total knee arthroplasty suggest that patients benefit more from the two-stage procedure. CONCLUSIONS: We strongly emphasize the employment of all possible means to prevent loosening, i. e., to use an appropriate surgical technique for primary implantation, to observe aseptic principles and to administer antibiotic therapy in conditions suspected of bacteremia. The shorter the interval between the onset of complaints and the reimplantation, the better results. Early loosening should be treated by two-stage surgery. Our method of bacteriological examination gives good results. Because of complexity of the problem, patients with a loose knee prosthesis should be referred to orthopedic departments with experienced and skilled surgical teams and high-quality examination facilities.With the observation of appropriate procedures, there is a great chance of achieving good results. Arthrodesis is still regarded as a justified "salvage" operation, particularly in cases with pre-operative findings of Staphylococcus aureus. Procedures for repeat surgery following the failure of a reimplanted joint have so far yielded doubtful results and still await further development.
16142730 Localized scleroderma in childhood is not just a skin disease. 2005 Sep OBJECTIVE: Juvenile localized scleroderma is usually considered a disease that is confined to the skin and subcutaneous tissue. We studied the prevalence and clinical features of extracutaneous manifestations in a large cohort of children with juvenile localized scleroderma. METHODS: Data from a multinational study on juvenile scleroderma was used for this in-depth study. Clinical features of patients with extracutaneous manifestations were compared with those of patients who had exclusively skin involvement. RESULTS: Seven hundred fifty patients entered the study. One hundred sixty-eight patients (22.4%) presented with a total of 193 extracutaneous manifestations, as follows: articular (47.2%), neurologic (17.1%), vascular (9.3%), ocular (8.3%), gastrointestinal (6.2%), respiratory (2.6%), cardiac (1%), and renal (1%). Other autoimmune conditions were present in 7.3% of patients. Neurologic involvement consisted of epilepsy, central nervous system vasculitis, peripheral neuropathy, vascular malformations, headache, and neuroimaging abnormalities. Ocular manifestations were episcleritis, uveitis, xerophthalmia, glaucoma, and papilledema. In more than one-fourth of these children, articular, neurologic, and ocular involvements were unrelated to the site of skin lesions. Raynaud's phenomenon was reported in 16 patients. Respiratory involvement consisted essentially of restrictive lung disease. Gastrointestinal involvement was reported in 12 patients and consisted exclusively of gastroesophageal reflux. Thirty patients (4%) had multiple extracutaneous features, but systemic sclerosis (SSc) developed in only 1 patient. In patients with extracutaneous involvement, the prevalence of antinuclear antibodies and rheumatoid factor was significantly higher than that among patients with only skin involvement. However, Scl-70 and anticentromere, markers of SSc, were not significantly increased. CONCLUSION: Extracutaneous manifestations of juvenile localized scleroderma developed in almost one-fourth of the children in this study. These extracutaneous manifestations often were unrelated to the site of the skin lesions and sometimes were associated with multiple organ involvement. The risk of developing SSc was very low. This subgroup of patients with juvenile localized scleroderma should be evaluated extensively, treated more aggressively, and monitored carefully.