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Search Results: 1 - 10 of 2029 matches for " Valentina Calamia "
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Glucosamine affects intracellular signalling through inhibition of mitogen-activated protein kinase phosphorylation in human chondrocytes
Anna Scotto d'Abusco, Valentina Calamia, Claudia Cicione, Brunella Grigolo, Laura Politi, Roberto Scandurra
Arthritis Research & Therapy , 2007, DOI: 10.1186/ar2307
Abstract: The pharmacological treatment of osteoarthritis (OA), a joint disorder characterized by slow, progressive degradation of the cartilage, includes analgesic agents and nonsteroidal antinflammatory drugs. During recent years there has been growing interest in alternative treatments for OA, such as glucosamine. In particular, glucosamine was found to be effective in reducing joint space narrowing compared with placebo in clinical trials conducted over a period of 3 years [1-4]. It was also found to be effective in decreasing pain compared with analgesic agents in OA of the knee [5,6]. A recent trial showed that glucosamine was ineffective in reducing pain in patients with severe knee OA, but it was more effective when it was used in combination with chondroitin sulphate in patients with moderate-to-severe pain [7].Cartilage degradation in OA is due to an imbalance between synthesis and degradation of extracellular matrix components. Proinflammatory cytokines, such as IL-1β, which are produced in OA, trigger several biological effects by stimulating mitogen-activated protein kinase (MAPK) phosphorylation. The latter results in activation of transcription factors [8-10], which in turn upregulate the production of several molecules such as matrix metalloproteases (MMPs) and aggrecanases. Increased enzymatic activity of MMPs and aggrecanases is the major factor responsible for matrix degradation [11,12].Several studies have examined the effects of glucosamine on MMP expression and activity in stimulated chondrocytes, obtained from various sources. The addition of glucosamine to cells appears to decrease the activity of MMPs [13-19]. Moreover, most in vitro studies conducted to elucidate the molecular basis of the effect of glucosamine on cartilage cells [20-24] demonstrated an anti-inflammatory and chondroprotective role for this molecule. However, the mechanisms responsible for these activities are not entirely understood.To address whether glucosamine can inhibit producti
Hsp90β inhibition modulates nitric oxide production and nitric oxide-induced apoptosis in human chondrocytes
Valentina Calamia, Maria C de Andrés, Natividad Oreiro, Cristina Ruiz-Romero, Francisco J Blanco
BMC Musculoskeletal Disorders , 2011, DOI: 10.1186/1471-2474-12-237
Abstract: Human OA chondrocytes were isolated from cartilage obtained from patients undergoing joint replacement surgery, and primary cultured. Cells were stimulated with proinflammatory cytokines (IL-1β or TNF-α) and nitric oxide donors (NOC-12 or SNP). For Hsp90β inhibition, two different chemical inhibitors (Geldanamycin and Novobiocin) were employed, or siRNA transfection procedures were carried out. Gene expression was determined by real-time PCR, apoptosis was quantified by flow cytometry and ELISA, and nitric oxide (NO) production was evaluated by the Griess method. Indirect immunofluorescence assays were performed to evaluate the presence of Hsp90β in stimulated cells.Hsp90β was found to be increased by proinflammatory cytokines. Inhibition of Hsp90β by the chemicals Geldanamycin (GA) and Novobiocin (NB) caused a dose-dependent decrease of the NO production induced by IL-1β in chondrocytes, up to basal levels. Immunofluorescence analyses demonstrate that the NO donors NOC-12 and SNP also increased Hsp90β. Chemical inhibition or specific gene silencing of this chaperone reduced the DNA condensation and fragmentation, typical of death by apoptosis, that is induced by NO donors in chondrocytes.The present results show how Hsp90β modulates NO production and NO-mediated cellular death in human OA chondrocytes.Osteoarthritis (OA) is a slowly progressive degenerative disease characterized by the degradation of the extracellular matrix (ECM) and cell death, resulting in a gradual loss of articular cartilage integrity, intra-articular inflammation and changes in peri-articular and subchondral bone [1]. The chondrocyte is the only cell type present in mature cartilage and is responsible for repairing the cartilage tissue damaged by OA.Chondrocytes are key players in the control of cartilage matrix turnover through the production and secretion of collagens, proteoglycans, and enzymes affecting cartilage metabolism [2]. Chondrocyte metabolism is influenced by several cytokines an
TNF and anti-TNF agents in Beh?et's disease
KT Calamia
Arthritis Research & Therapy , 2003, DOI: 10.1186/ar981
Abstract: Hassard (2001) reported rapid and dramatic improvement in gastrointestinal and extraintestinal symptoms and findings of the disorder after treatment with infliximab. Similar response was seen in two other patients treated by Travis (2001). This experience was followed by the report of Robertson (2001) of a patient free of oral and genital ulcerations for the first time in 10 years after three infusions of infliximab. Remission of mucocutaneous symptoms for one year followed two infusions of infliximab in a patient previously uncontrolled by multiple immunosuppressive agents (Goossens, 2001). Mucocutaneous lesions remitted with infliximab in a patient with Beh?et's disease associated with rheumatoid arthritis (Rozenbaum, 2002). At EULAR 2002, Turkish investigators reported the results of the first double-masked, placebo-controlled study (n = 40) of anti-TNF therapy with etanercept in mucocutaneous Beh?et's disease (Melikoglu, 2002). This agent suppressed disease manifestations with resurgence after the drug was discontinued. Additional recent reports of anti-TNF therapies in Beh?et's disease were presented at several international meetings.The experience with anti-TNF-α treatments for the ocular manifestations of Beh?et's disease has been growing and very positive. Sfikakis (2001) reported the benefits of infliximab in five patients with panuveitis in Beh?et's disease. This included two patients treated with infliximab therapy without an increase in conventional treatment. At the ACR meeting in 2002 these Greek investigators reported successful monotherapy with infliximab in acute ocular inflammation in Beh?et's disease in 14 patients. The authors suggested that the dramatic and rapid response in these patients would favor the use of this agent over conventional therapy. Positive responses to anti-TNF agents in ocular Beh?et's disease have been documented in numerous case reports in the literature or presentations at international meetings.Significant differences exi
Premessa
Mario Calamia
Aestimum , 1989,
Abstract:
Sequential depletion of human serum for the search of osteoarthritis biomarkers
Fernández-Costa Carolina,Calamia Valentina,Fernández-Puente Patricia,Capelo-Martínez José-Luis
Proteome Science , 2012, DOI: 10.1186/1477-5956-10-55
Abstract: Background The field of biomarker discovery, development and application has been the subject of intense interest and activity, especially with the recent emergence of new technologies, such as proteomics-based approaches. In proteomics, search for biomarkers in biological fluids such as human serum is a challenging issue, mainly due to the high dynamic range of proteins present in these types of samples. Methods for reducing the content of most highly abundant proteins have been developed, including immunodepletion or protein equalization. In this work, we report for the first time the combination of a chemical sequential depletion method based in two protein precipitations with acetonitrile and DTT, with a subsequent two-dimensional difference in-gel electrophoresis (2D-DIGE) analysis for the search of osteoarthritis (OA) biomarkers in human serum. The depletion method proposed is non-expensive, of easy implementation and allows fast sample throughput. Results Following this workflow, we have compared sample pools of human serum obtained from 20 OA patients and 20 healthy controls. The DIGE study led to the identification of 16 protein forms (corresponding to 14 different proteins) that were significantly (p < 0.05) altered in OA when compared to controls (8 increased and 7 decreased). Immunoblot analyses confirmed for the first time the increase of an isoform of Haptoglobin beta chain (HPT) in sera from OA patients. Conclusions Altogether, these data demonstrate the utility of the proposed chemical sequential depletion for the analysis of sera in protein biomarker discovery approaches, exhibit the usefulness of quantitative 2D gel-based strategies for the characterization of disease-specific patterns of protein modifications, and also provide a list of OA biomarker candidates for validation.
Oligomerization of Sulfolobus solfataricus signature amidase is promoted by acidic pH and high temperature
Anna Scotto D’Abusco,Rita Casadio,Gianluca Tasco,Laura Giangiacomo,Anna Giartosio,Valentina Calamia,Stefania Di Marco,Roberta Chiaraluce,Valerio Consalvi,Roberto Scandurra,Laura Politi
Archaea , 2005, DOI: 10.1155/2005/543789
Abstract: The recombinant amidase from the hyperthermophylic archaeon Sulfolobus solfataricus (SSAM) a signature amidase, was cloned, purified and characterized. The enzyme is active on a large number of aliphatic and aromatic amides over the temperature range 60–95 °C and at pH values between 4.0 and 9.5, with an optimum at pH 5.0. The recombinant enzyme is in the form of a dimer of about 110 kD that reversibly associates into an octamer in a pH-dependent reaction. The pH dependence of the state of association was studied using gel permeation chromatography, analytical ultracentrifugation and dynamic light scattering techniques.
Pharmacoproteomic study of the effects of chondroitin and glucosamine sulfate on human articular chondrocytes
Valentina Calamia, Cristina Ruiz-Romero, Beatriz Rocha, Patricia Fernández-Puente, Jesús Mateos, Eulàlia Montell, Josep Vergés, Francisco J Blanco
Arthritis Research & Therapy , 2010, DOI: 10.1186/ar3077
Abstract: Chondrocytes obtained from three healthy donors were treated with GS 10 mM and/or CS 200 μg/mL, and then stimulated with interleukin-1β (IL-1β) 10 ng/mL. Whole cell proteins were isolated 24 hours later and resolved by two-dimensional electrophoresis. The gels were stained with SYPRORuby. Modulated proteins were identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF/TOF) mass spectrometry. Real-time PCR and Western blot analyses were performed to validate our results.A total of 31 different proteins were altered by GS or/and CS treatment when compared to control. Regarding their predicted biological function, 35% of the proteins modulated by GS are involved in signal transduction pathways, 15% in redox and stress response, and 25% in protein synthesis and folding processes. Interestingly, CS affects mainly energy production (31%) and metabolic pathways (13%), decreasing the expression levels of ten proteins. The chaperone GRP78 was found to be remarkably increased by GS alone and in combination with CS, a fact that unveils a putative mechanism for the reported anti-inflammatory effect of GS in OA. On the other hand, the antioxidant enzyme superoxide dismutase 2 (SOD2) was significantly decreased by both drugs and synergistically by their combination, thus suggesting a drug-induced decrease of the oxidative stress caused by IL-1β in chondrocytes.CS and GS differentially modulate the proteomic profile of human chondrocytes. This pharmacoproteomic approach unravels the complex intracellular mechanisms that are modulated by these drugs on IL1β-stimulated human articular chondrocytes.Osteoarthritis (OA) is becoming increasingly prevalent worldwide because of the combination of an aging population and growing levels of obesity. Despite the increasing number of OA patients, treatments to manage this disease are limited to controlling pain and improving function and quality of life while limiting adverse events [1]. Effective therapies to regene
Beh et’s disease: an update on pathogenesis, diagnosis and management of vascular involvement
Phaedon G. Kaklamanis,Kenneth T. Calamia
Rheumatology Reports , 2010, DOI: 10.4081/rr.2010.e2
Abstract: The objective of this review is to summarize reports of the prevalence, clinical presentation, diagnostic methodology and treatment of vasculitic manifestations of Beh et’s disease (BD). We performed a literature search on vasculitis in BD. Articles were selected which provided insight into the pathogenesis and clinical aspects of vasculitis. Vasculitis underlies many of the clinical features of BD. Small vessel vasculitis is often found in the pathology of the mucocutaneous manifestations of BD. Large vessel vasculitis has been reported in 15-40% of BD patients. Ultrasound, angiography and tomography are applied to confirm the diagnosis when venous involvement is suspected. Endothelial dysfunction plays a role in the pathogenesis of disease. Peripheral arterial involvement in BD occurs in the form of arterial occlusion or aneurysms. Pulmonary arterial involvement is often life-threatening. The cause of cardiac vascular involvement requires an aggressive diagnostic approach. Corticosteroids and immunosuppressive agents have been used successfully in the early stage of large vessel disease and should be used as an adjunct to surgery. An increasing amount of data is available regarding the role of anti-tumor necrosis factor (TNF) agents for the treatment of BD. Anticoagulant therapy may be hazardous in patients with aneurysmal dilatation of the pulmonary vascular tree and is not effective in the treatment of venous thrombosis. Inflammation of small and large vessels is very frequent in BD. Both arteries and veins may be involved. Early recognition and appropriate management of large vessel vasculitis in BD is essential to reduce associated morbidity and mortality.
Fast Time-Domain Edge-Diffraction Calculations for Interactive Acoustic Simulations
Calamia Paul T,Svensson U Peter
EURASIP Journal on Advances in Signal Processing , 2007,
Abstract: The inclusion of edge diffraction has long been recognized as an improvement to geometrical-acoustics (GA) modeling techniques, particularly for acoustic simulations of complex environments that are represented as collections of finite-sized planar surfaces. One particular benefit of combining edge diffraction with GA components is that the resulting total sound field is continuous when an acoustic source or receiver crosses a specular-zone or shadow-zone boundary, despite the discontinuity experienced by the associated GA component. In interactive acoustic simulations which include only GA components, such discontinuities may be heard as clicks or other undesirable audible artifacts, and thus diffraction calculations are important for high perceptual quality as well as physical realism. While exact diffraction calculations are difficult to compute at interactive rates, approximate calculations are possible and sufficient for situations in which the ultimate goal is a perceptually plausible simulation rather than a numerically exact one. In this paper, we describe an edge-subdivision strategy that allows for fast time-domain edge-diffraction calculations with relatively low error when compared with results from a more numerically accurate solution. The tradeoff between computation time and accuracy can be controlled with a number of parameters, allowing the user to choose the speed that is necessary and the error that is tolerable for a specific modeling scenario.
Fast Time-Domain Edge-Diffraction Calculations for Interactive Acoustic Simulations
Paul T. Calamia,U. Peter Svensson
EURASIP Journal on Advances in Signal Processing , 2007, DOI: 10.1155/2007/63560
Abstract: The inclusion of edge diffraction has long been recognized as an improvement to geometrical-acoustics (GA) modeling techniques, particularly for acoustic simulations of complex environments that are represented as collections of finite-sized planar surfaces. One particular benefit of combining edge diffraction with GA components is that the resulting total sound field is continuous when an acoustic source or receiver crosses a specular-zone or shadow-zone boundary, despite the discontinuity experienced by the associated GA component. In interactive acoustic simulations which include only GA components, such discontinuities may be heard as clicks or other undesirable audible artifacts, and thus diffraction calculations are important for high perceptual quality as well as physical realism. While exact diffraction calculations are difficult to compute at interactive rates, approximate calculations are possible and sufficient for situations in which the ultimate goal is a perceptually plausible simulation rather than a numerically exact one. In this paper, we describe an edge-subdivision strategy that allows for fast time-domain edge-diffraction calculations with relatively low error when compared with results from a more numerically accurate solution. The tradeoff between computation time and accuracy can be controlled with a number of parameters, allowing the user to choose the speed that is necessary and the error that is tolerable for a specific modeling scenario.
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