Synovial Fluid (synovial + fluid)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Assessment of Five Interleukins in Human Synovial Fluid as Possible Markers for Aseptic Loosening of Hip Arthroplasty

ARTIFICIAL ORGANS, Issue 7 2009
Alina Beraudi
Abstract One of the most important factors that seems to be involved in total hip replacement is periprosthetic osteolysis. As it is well documented that several interleukins (ILs) are triggered in periprosthetic osteolysis, this article investigates the role of five ILs in primary and replacement total hip arthroplasty, understanding if one of them can also predict hip implant loosening, secondary surgery, and prosthesis breakage. The levels of IL-1,, 1,, 6, 8, and 10 in synovial fluid were examined, using a high sensitivity enzyme-linked immunosorbent assay (ELISA) test kit (Pierce Biotechnology, Inc., Rockford, IL, USA) to determine whether these cytokines could be used as markers of enhanced periprosthetic osteolysis, leading to aseptic loosening of total/partial hip arthroplasty or revision surgery. Synovial fluid was harvested from 23 patients undergoing primary total hip arthroplasty and 35 patients undergoing total/partial hip revision due to aseptic loosening. In the revision group, four cases had suffered a prosthesis fracture and five were second revisions. ILs 6 and 8 were significantly higher in the revisions (305 and 817 pg/mL) compared with the primary arthroplasties (151 and 151 pg/mL), including cases with prosthesis fracture and those requiring a second revision. IL-10 levels were lower (not significantly) in second revision samples compared with those of revision samples. IL-1, levels were significantly higher in prosthesis fracture samples compared with those of all the other revision samples. No statistically significant differences in IL levels were found between osteoarthritis samples and those of other diseases. These results are a step forward to elucidating the complex network of events that are involved in loosening of hip implants. [source]


Evidence supporting an increased presence of reactive oxygen species in the diseased equine joint

EQUINE VETERINARY JOURNAL, Issue 5 2000
A. N. Dimock
Summary Reactive oxygen species (ROS) are capable of degrading many components of the joint in the presence of insufficient antioxidant defences, and as a result have been implicated in the pathogenesis of joint disease in horses. However, to our knowledge, evidence of ROS occurring in diseased joints of horses has not been reported. The objective of this experiment was to compare differences in synovial fluid protein carbonyl content (as a marker of oxidative modification of synovial fluid proteins by ROS) and the antioxidant status of synovial fluid between clinically normal and diseased equine joints. Synovial fluid was collected from the metacarpophalangeal, metatarsophalangeal, carpal and tarsal joints of 4 horses, age 2,5 years, as controls, and from diseased joints (metacarpophalangeal, metatarsophalangeal, carpal, tarsal and/or femoropatellar) of 61 horses, age 2,5 years. Synovial fluid protein carbonyl content was higher (P<0.01) in diseased joints as compared to controls. Antioxidant status of synovial fluid from diseased joints was higher, but not significantly, than that of controls (P = 0.0595). These findings require further study to determine their contribution to the overall disease process. [source]


Synovial fluid at microwave frequencies

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2007
Anil Lonappan
Abstract Arthritis is one of the most pervasive diseases that causes of disability. For most people arthritis pain and inflammation cannot be avoided as the body ages. The present communication reports the study on the synovial fluid has the main lubricant in joints collected from normal persons and those ailing from arthritis are subjected to the microwave study and the variations of the dielectric parameters are investigated. The in vitro measurements of synovial fluid samples are done using cavity perturbation technique in the frequency range of 2,3 GHz. It is observed that in this band, the dielectric constant of normal samples are higher than those of arthritis affected ones and conductivity of is higher in normal samples, which finds application in detecting arthritis using microwaves. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1700,1702, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22552 [source]


Inflammatory cytokine regulation of transgene expression in human fibroblast-like synoviocytes infected with adeno-associated virus

ARTHRITIS & RHEUMATISM, Issue 7 2006
Russell S. Traister
Objective An ideal gene transfer vector for chronic inflammatory diseases such as rheumatoid arthritis (RA) would provide local transgene expression only when the disease is active. To determine whether adeno-associated virus (AAV) possesses this ability, the effects of inflammatory cytokines on transgene expression were evaluated in human RA fibroblast-like synoviocytes (FLS). Methods Human FLS were infected with AAV in the presence or absence of inflammatory cytokines or synovial fluid obtained from patients with RA. Transgene expression was monitored by either enzyme-linked immunosorbent assay or flow cytometry. Transgene messenger RNA (mRNA) was measured by real-time quantitative reverse transcription,polymerase chain reaction. Results Inflammatory cytokines increased transgene expression in FLS by up to 60-fold. Synovial fluid from patients with RA, but not from patients without arthritis, was also able to increase expression in synoviocytes. Protein expression correlated with transgene mRNA levels. The enhanced expression required the continued presence of cytokines because, upon removal, transgene expression returned to baseline levels. Expression could be repeatedly reinduced by reexposure to cytokines. The effect was not promoter specific and was demonstrated to be phosphatidylinositol 3-kinase,dependent. Conclusion These results suggest that expression of a therapeutic transgene can be controlled by the presence of inflammation following AAV gene transfer, making it an attractive vector for chronic inflammatory diseases such as RA. [source]


Assessment of Five Interleukins in Human Synovial Fluid as Possible Markers for Aseptic Loosening of Hip Arthroplasty

ARTIFICIAL ORGANS, Issue 7 2009
Alina Beraudi
Abstract One of the most important factors that seems to be involved in total hip replacement is periprosthetic osteolysis. As it is well documented that several interleukins (ILs) are triggered in periprosthetic osteolysis, this article investigates the role of five ILs in primary and replacement total hip arthroplasty, understanding if one of them can also predict hip implant loosening, secondary surgery, and prosthesis breakage. The levels of IL-1,, 1,, 6, 8, and 10 in synovial fluid were examined, using a high sensitivity enzyme-linked immunosorbent assay (ELISA) test kit (Pierce Biotechnology, Inc., Rockford, IL, USA) to determine whether these cytokines could be used as markers of enhanced periprosthetic osteolysis, leading to aseptic loosening of total/partial hip arthroplasty or revision surgery. Synovial fluid was harvested from 23 patients undergoing primary total hip arthroplasty and 35 patients undergoing total/partial hip revision due to aseptic loosening. In the revision group, four cases had suffered a prosthesis fracture and five were second revisions. ILs 6 and 8 were significantly higher in the revisions (305 and 817 pg/mL) compared with the primary arthroplasties (151 and 151 pg/mL), including cases with prosthesis fracture and those requiring a second revision. IL-10 levels were lower (not significantly) in second revision samples compared with those of revision samples. IL-1, levels were significantly higher in prosthesis fracture samples compared with those of all the other revision samples. No statistically significant differences in IL levels were found between osteoarthritis samples and those of other diseases. These results are a step forward to elucidating the complex network of events that are involved in loosening of hip implants. [source]


Use of biodegradable urethane-based adhesives to appose meniscal defect edges in an ovine model: a preliminary study

AUSTRALIAN VETERINARY JOURNAL, Issue 6 2008
JR FIELD
Objective To evaluate the biological response to two urethane-based adhesives used to repair full thickness meniscal wounds created in the partially vascularised (red-white) zone. Design An ovine bilateral meniscal defect model was used to evaluate the initial biological response of the meniscal cartilage and synovium over a 1-month period. A 10-mm full-thickness defect was created in the medial meniscus of each femorotibial joint. The defects were either left untreated or repaired using the urethane-based adhesives. Synovial fluid, synovial membrane and the meniscal cartilages were retrieved at necropsy for cytological and histological assessment. Results The ovine model proved to be a suitable system for examining meniscal repair. Untreated defects showed no tissue apposition or cellular healing response, whereas all eight defects repaired with the two urethane-based adhesive formulations showed signs of repair and tissue regeneration with indications of cell infiltration and new collagen deposition in and around the polymer. No adverse cellular response to the adhesives was observed in the meniscal defect or in the synovial membrane and fluid. Conclusion Trauma to the knee commonly results in tears to the meniscal cartilage, with the majority of these occurring in the partially vascularised (red-white) or non-vascularised (white) zones of the meniscus. Repair, and subsequent healing, of these tears is poor because of the reduced vascularity and limited surgical access. The present data indicate that an ovine model is a suitable system for examining meniscal repair, and that development of urethane-based adhesives offers a strategy that may be clinically effective for the treatment of these injuries. [source]


CD13/aminopeptidase N,induced lymphocyte involvement in inflamed joints of patients with rheumatoid arthritis

ARTHRITIS & RHEUMATISM, Issue 9 2002
Teruki Shimizu
Objective We previously showed that CD13/aminopeptidase N (EC 3.4.11.2) induces chemotactic migration of T lymphocytes by its enzymatic activity. In this study, we examined the role of CD13/aminopeptidase N in lymphocyte involvement in rheumatoid arthritis (RA). Methods Synovial fluids were obtained from 27 RA patients and 6 osteoarthritis (OA) patients. Synovial tissue specimens were obtained from 3 RA patients and 3 OA patients. Protease activity of aminopeptidase in synovial fluids and synovial fibroblasts was assayed fluorometrically using the specific substrate. Expression of CD13/aminopeptidase N in synovial fibroblasts was determined by flow cytometry analyses, Western blotting, and reverse transcriptase,polymerase chain reaction (RT-PCR). Results The mean value of aminopeptidase activity in synovial fluid samples from RA patients was significantly higher than that in samples from OA patients. Increased enzymatic activity of aminopeptidase was detected on synovial fibroblasts from RA patients compared with those from OA patients. Flow cytometry showed that the expression of CD13/aminopeptidase N on synovial fibroblasts from RA patients was higher than the expression on synovial fibroblasts from OA patients, and Western blots and RT-PCR showed that synovial fibroblasts from RA patients contained a greater amount of CD13/aminopeptidase N. The activity of CD13/aminopeptidase N correlated significantly with lymphocyte counts in synovial fluids from RA patients. Synovial fluids from RA patients in which high aminopeptidase activity was detected contained considerable chemotactic activity for lymphocytes, and bestatin, a specific inhibitor of aminopeptidases, partially inhibited the chemotactic activity. Conclusion CD13/aminopeptidase N may participate in the mechanism of lymphocyte involvement in inflamed joints of RA patients as a lymphocyte chemoattractant. [source]


The BSCC Code of Practice , exfoliative cytopathology (excluding gynaecological cytopathology)

CYTOPATHOLOGY, Issue 4 2009
A. Chandra
Exfoliative cytopathology (often referred to as non-gynaecological cytology) is an important part of the workload of all diagnostic pathology departments. It clearly has a role in the diagnosis of neoplastic disease but its role in establishing non-neoplastic diagnoses should also be recognised. Ancillary tests may be required to establish a definitive diagnosis. Clinical and scientific teamwork is essential to establish an effective cytology service and staffing levels should be sufficient to support preparation, prescreening, on-site adequacy assessment and reporting of samples as appropriate. Routine clinical audit and histology/cytology correlation should be in place as quality control of a cytology service. Cytology staff should be involved in multidisciplinary meetings and appropriate professional networks. Laboratories should have an effective quality management system conforming to the requirements of a recognised accreditation scheme such as Clinical Pathology Accreditation (UK) Ltd. Consultant pathologists should sign out the majority of exfoliative cytology cases. Where specimens are reported by experienced biomedical scientists (BMS), referred to as cytotechnologists outside the UK, this must only be when adequate training has been given and be defined in agreed written local protocols. An educational basis for formalising the role of the BMS in exfoliative cytopathology is provided by the Diploma of Expert Practice in Non-gynaecological Cytology offered by the Institute of Biomedical Science (IBMS). The reliability of cytological diagnoses is dependent on the quality of the specimen provided and the quality of the preparations produced. The laboratory should provide feedback and written guidance on specimen procurement. Specimen processing should be by appropriately trained, competent staff with appropriate quality control. Microscopic examination of preparations by BMS should be encouraged wherever possible. Specific guidance is provided on the clinical role, specimen procurement, preparation and suitable staining techniques for urine, sputum, semen, serous cavity effusion, cerebrospinal fluid, synovial fluid, cyst aspirates, endoscopic specimens, and skin and mucosal scrapes. [source]


Evidence supporting an increased presence of reactive oxygen species in the diseased equine joint

EQUINE VETERINARY JOURNAL, Issue 5 2000
A. N. Dimock
Summary Reactive oxygen species (ROS) are capable of degrading many components of the joint in the presence of insufficient antioxidant defences, and as a result have been implicated in the pathogenesis of joint disease in horses. However, to our knowledge, evidence of ROS occurring in diseased joints of horses has not been reported. The objective of this experiment was to compare differences in synovial fluid protein carbonyl content (as a marker of oxidative modification of synovial fluid proteins by ROS) and the antioxidant status of synovial fluid between clinically normal and diseased equine joints. Synovial fluid was collected from the metacarpophalangeal, metatarsophalangeal, carpal and tarsal joints of 4 horses, age 2,5 years, as controls, and from diseased joints (metacarpophalangeal, metatarsophalangeal, carpal, tarsal and/or femoropatellar) of 61 horses, age 2,5 years. Synovial fluid protein carbonyl content was higher (P<0.01) in diseased joints as compared to controls. Antioxidant status of synovial fluid from diseased joints was higher, but not significantly, than that of controls (P = 0.0595). These findings require further study to determine their contribution to the overall disease process. [source]


A carbohydrate neoepitope that is up-regulated on human mononuclear leucocytes by neuraminidase treatment or by cellular activation

IMMUNOLOGY, Issue 2 2001
Mark T. Quinn
Summary The expression of cell-surface antigens can delineate specific leucocyte developmental or functional stages. For example, certain membrane glycoproteins are expressed selectively on leucocyte subsets only after activation. Leucocyte activation can also induce changes in carbohydrate epitopes expressed on surface antigens. In the present studies, we report on a novel monoclonal immunoglobulin M antibody (mAb 13.22) that recognizes a unique carbohydrate epitope expressed on human leucocyte membrane proteins. Characterization of mAb 13.22 specificity by immunoblotting showed that it recognized proteins of MW ,95 000 and 150 000, including both CD18 and CD11b. The mAb 13.22 epitope was removed by N -glycosidase F but not by endoglycosidase H or fucosidase, demonstrating that it is an N-linked carbohydrate antigen. Interestingly, immunoblot staining was enhanced after neuraminidase treatment, suggesting that the antibody epitope might also be partially masked by sialic acid. In resting leucocytes, the mAb 13.22 antigen was expressed strongly on neutrophils, while dull staining was present on monocytes, and no lymphocyte staining was observed. In marked contrast, treatment of leucocytes with neuraminidase resulted in exposure of a mAb 13.22 neoepitope on a subset of lymphocytes (primarily T lymphocytes and natural killer cells) as well as up-regulated staining more than 18-fold on monocytes. Activation of lymphocytes in culture with phytohaemagglutinin or concanavalin A also unmasked the mAb 13.22 neoepitope on ,37% of the CD45RO+ lymphocytes. Furthermore, analysis of leucocytes collected from the synovial fluid of patients with rheumatoid arthritis showed that ,18% of the lymphocytes present expressed the mAb 13.22 neoepitope. Taken together, our results suggest that the mAb 13.22 carbohydrate neoepitope could represent a physiologically relevant marker that is up-regulated on leucocyte subsets during the inflammatory response. [source]


Regulation of human neutrophil-mediated cartilage proteoglycan degradation by phosphatidylinositol-3-kinase

IMMUNOLOGY, Issue 1 2001
C. S. T. Hii
Summary The ability of neutrophils to degrade cartilage proteoglycan suggests that the neutrophils that accumulate in the joints of rheumatoid arthritis patients are mediators of tissue damage. The regulatory mechanisms which are relevant to the proteoglycan-degrading activity of neutrophils are poorly understood. Since phosphatidylinositol 3-kinase (PI3-K), protein kinase C (PKC), the extracellular signal-regulated protein kinase (ERK)1/ERK2 and cyclic adenosine monophosphate (cAMP) have been reported to regulate neutrophil respiratory burst and/or degranulation, a role for these signalling molecules in regulating proteoglycan degradation was investigated. Preincubation of human neutrophils with GF109203X (an inhibitor of PKC), PD98059 (an inhibitor of MEK, the upstream regulator of ERK1/ERK2) or with forskolin or dibutyryl cAMP, failed to suppress proteoglycan degradation of opsonized bovine cartilage. In contrast, preincubation of neutrophils with wortmannin or LY294002, specific inhibitors of PI3-K, inhibited proteoglycan degradation. Incubation of neutrophils with cartilage resulted in the activation of PI3-K in neutrophils, consistent with a role for PI3-K in proteoglycan degradation. Activation of PI3-K and proteoglycan degradation was enhanced by tumour necrosis factor-,. Degradation caused by neutrophils from the synovial fluid of rheumatoid arthritis patients was also inhibited by wortmannin. These data demonstrate that the proteoglycan degradative activity of neutrophils required PI3-K but not PKC or the ERK1/ERK2/ERK5 cascades and was insensitive to increases in intracellular cAMP concentrations. [source]


Lipid peroxidation, glutathione, vitamin E, and antioxidant enzymes in synovial fluid from patients with osteoarthritis

INTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 4 2009
Werasak SUTIPORNPALANGKUL
Abstract Aim:, To compare levels of lipid peroxidation and antioxidants in synovial fluid from primary knee osteoarthritis (OA) patients with severe cartilage damage undergoing total knee replacement with those in the synovial fluid from injured knee joint patients with intact cartilage undergoing knee arthroscopy. Methods:, Thirty-two OA patients and 10 injured knee joint patients were recruited. Lipid peroxidation (thiobarbituric acid reactive substances [TBARs]), iron and glutathione (GSH) were measured using a colorimetric method. Vitamin E was measured with high-performance liquid chromatography (HPLC). Activities of antioxidant enzymes (glutathione peroxidase [GPx], superoxide dismutase [SOD]) were analyzed with the use of a kinetic method. Results:, TBARs, iron and GSH levels in synovial fluid were not significantly different between OA patients and injured knee joint patients. Antioxidant enzymes such as GPx and SOD activities also indicated no significant difference. Only vitamin E level was significantly lower in the synovial fluid of OA patients than in that of the injured knee joint patients. Conclusions:, Oxidative stress may have a role in pathogenesis of knee osteoarthritis. Vitamin E supplementation may have a role in the management of patients. [source]


Epidermal growth factor stimulates proton efflux from chondrocytic cells

JOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2002
Kevin E.H. Lui
Proton efflux from chondrocytes alters the extracellular pH and ionic composition of cartilage, and influences the synthesis and degradation of extracellular matrix. Epidermal growth factor (EGF) promotes chondrocyte proliferation during skeletal development and accumulates in the synovial fluid in rheumatoid arthritis. The purpose of this study was to investigate the effect of EGF on proton efflux from chondrocytes. When monitored using a Cytosensor microphysiometer, EGF was found to rapidly activate proton efflux from CFK2 chondrocytic cells and rat articular chondrocytes. The actions of EGF were concentration-dependent with half-maximal effects at 0.3,0.7 ng/ml. Partial desensitization and time-dependent recovery of the response were observed following repeated exposures to EGF. EGF-induced proton efflux was dependent on extracellular glucose, and inhibitors of Na+/H+ exchange (NHE) markedly attenuated the initial increase in proton efflux. The response was diminished by inhibitors of phosphatidylinositol 3-kinase and phospholipase C, but not by inhibitors of MEK (MAPK/ERK kinase) or protein kinase A or C. Thus, EGF-induced proton efflux involves glucose metabolism and NHE, and is regulated by a discrete subset of EGF-activated signaling pathways. In vivo, proton efflux induced by EGF may lead to an acidic environment, enhancing turnover of cartilage matrix during development and in rheumatoid arthritis. © 2002 Wiley-Liss, Inc. [source]


Detection of periodontal bacterial DNA in serum and synovial fluid in refractory rheumatoid arthritis patients

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2009
Rita E. Martinez-Martinez
Abstract Aim: To identify periodontal bacterial DNA (PBDNA) by PCR in subgingival dental plaque (SDP), serum and synovial fluid (SF) of rheumatoid arthritis (RA) with periodontal disease (PD) patients and to explore the possible PBDNA transport pathways from mouth to joints. Methods: This cross-sectional prolective study involved 19 subjects with RA and PD. Informed consent, health and dental questionnaires were obtained. SDP, SF and serum samples were obtained, and leucocytes were isolated from blood. DNA was extracted and PCR assays to detect main PD species were carried out. Cultures on agar plates and broth, from each sample, were performed. Results: Hundred percentage of patients showed PBDNA in SDP and SF and 83.5% in serum. Prevotella intermedia (89.4% and 73.6%) and Porphyromonas gingivalis (57.8% and 42.1%) were the species most frequently detected in SDP and SF, respectively. In SDP, 4.05 different bacterial species were found followed by 1.19 in serum and 2.26 in SF. Culture onto agar plates and broth did not show any bacterial growth, leucocytes were not positive to PBDNA by PCR. Conclusion: This study suggests that PBDNA could have a role on the RA aetiology. The possible pathway of transport of PBDNA from mouth to joints could be via the free form of DNA. [source]


Kynurenine inhibits chondrocyte proliferation and is increased in synovial fluid of patients with septic arthritis

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 11 2010
Tim T. Lögters
Abstract Kynurenine, the major degradation product of tryptophan has been shown to directly damage various tissues. Its potential contribution to septic arthritis is unknown. In this study, we analyzed the putative diagnostic value of kynurenine for bacterial joint infection and its potential harmful effects on cartilage. In a prospective study 41 patients with a joint effusion who had undergone arthrocentesis were included. Tryptophan and kynurenine levels from synovial fluid were quantified by HPLC. Diagnostic value of kynurenine was evaluated and its effects on the proliferation of the chondrocyte cell line ATDC5 were determined. Synovial fluid kynurenine values from patients with septic arthritis (4.1,±,0.8,µmol/L, n,=,9) were significantly increased compared to patients with non-infectious inflammatory arthropathy (1.8,±,0.2,µmol/L, n,=,17) or osteoarthritis (1.2,±,0.1,µmol/L, n,=,15, p,<,0.01). At a cut-off value of 2.28,µmol/L kynurenine had a sensitivity of 0.89 and a specificity of 0.87. Further, kynurenine inhibited chondrocyte (ATDC5) cell proliferation in a dose-dependent manner. Septic arthritis is associated with significantly increased values of synovial kynurenine. Furthermore kynurenine inhibits proliferation of chondrocytes, which strongly suggests a pathophysiological effect of kynurenine on cartilage in inflammatory arthropathies. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1490,1496, 2010 [source]


Wear mechanisms in metal-on-metal bearings: The importance of tribochemical reaction layers

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2010
Markus A. Wimmer
Abstract Metal-on-metal (MoM) bearings are at the forefront in hip resurfacing arthroplasty. Because of their good wear characteristics and design flexibility, MoM bearings are gaining wider acceptance with market share reaching nearly 10% worldwide. However, concerns remain regarding potential detrimental effects of metal particulates and ion release. Growing evidence is emerging that the local cell response is related to the amount of debris generated by these bearing couples. Thus, an urgent clinical need exists to delineate the mechanisms of debris generation to further reduce wear and its adverse effects. In this study, we investigated the microstructural and chemical composition of the tribochemical reaction layers forming at the contacting surfaces of metallic bearings during sliding motion. Using X-ray photoelectron spectroscopy and transmission electron microscopy with coupled energy dispersive X-ray and electron energy loss spectroscopy, we found that the tribolayers are nanocrystalline in structure, and that they incorporate organic material stemming from the synovial fluid. This process, which has been termed "mechanical mixing," changes the bearing surface of the uppermost 50 to 200 nm from pure metallic to an organic composite material. It hinders direct metal contact (thus preventing adhesion) and limits wear. This novel finding of a mechanically mixed zone of nanocrystalline metal and organic constituents provides the basis for understanding particle release and may help in identifying new strategies to reduce MoM wear. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:436,443, 2010 [source]


MMP-mediated collagen breakdown induced by activated protein C in equine cartilage is reduced by corticosteroids

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2010
Elaine R. Garvican
Abstract The plasma serine protease activated protein C (APC) is synthesized by human chondrocytes at sites of pathological cartilage fibrillation. APC levels are increased in osteoarthritis (OA) synovial fluid, and in vitro APC has been shown to synergize with interleukin-1, (IL-1) to promote degradation from ovine cartilage. A model of equine cartilage degradation was established and used to explore corticosteroid activities. Intraarticular corticosteroids are a commonly prescribed treatment for joint disease, however their role in disease modification remains unclear. APC synergized with IL-1 or tumor necrosis factor-, (TNF,), promoting significant collagen degradation from equine cartilage explants within 4 days, but did not augment glycoaminoglycan (GAG) release. APC activated pro-matrix metalloproteinases (MMP)-2 but not pro-MMP-9, as assessed by gelatin zymography. APC did not directly activate pro-MMP-13. Dexamethasone, triamcinolone, and methylprednisolone acetate (MPA) were evaluated at concentrations between 10, 5M and 10,10M. High concentrations significantly increased GAG release from IL-1+APC,treated explants. With the exception of MPA at 10,10M, all concentrations of corticosteroids caused significant decreases in IL-1+APC-driven hydroxyproline loss. Treatment with corticosteroids suppressed expression of MMP-1, -3, and -13 mRNA. The collagenolysis associated with IL-1+APC synergy, and the inhibition of this effect by corticosteroids may involve gelatinase activation and downregulation of MMP expression, respectively. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:370,378, 2010 [source]


PRG4 exchange between the articular cartilage surface and synovial fluid

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 10 2007
G.E. Nugent-Derfus
Abstract The boundary lubrication function of articular cartilage is mediated in part by proteoglycan 4 (PRG4) molecules, found both in synovial fluid (SF) and bound to the articular cartilage surface. Currently the mechanism by which PRG4 binds to the articular surface is not well understood. The objectives of this study were to determine (1) the effect of bathing fluid contents on PRG4 concentration at the articular surface ([PRG4]cart), and (2) whether native PRG4 can be removed from the surface and subsequently repleted with PRG4 from synovial fluid. In one experiment, cylindrical cartilage disks were stored in solutions of various PRG4 concentrations, either in phosphate-buffered saline (PBS) or SF as the carrier fluid. In a separate experiment, cartilage disks were stored in solutions expected to remove native PRG4 from the articular surface and allow subsequent repletion with PRG4 from SF. [PRG4]cart was independent of PRG4 concentration of the bathing fluid, and was similar for both carrier fluids. PRG4 was removed from cartilage by treatment with hyaluronidase, reduction/alkylation, and sodium dodecyl sulphate, and was repleted fully by subsequent bathing in SF. These results suggest that the articular surface is normally saturated with tightly bound PRG4, but this PRG4 can exchange with the PRG4 in SF under certain conditions. This finding suggests that all tissues surrounding the joint cavity that secrete PRG4 into the SF may help to maintain lubrication function at the articular surface. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1269,1276, 2007 [source]


Myeloperoxidase and chlorinated peptides in osteoarthritis: potential biomarkers of the disease

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 9 2007
Marla J. Steinbeck
Abstract Osteoarthritis (OA) is a disabling condition in which multiple initiating events or conditions (heritable and nonheritable) result in eventual loss of articular cartilage. However, the etiology of OA remains poorly understood, and diagnosis of early disease is difficult due to the lack of specific identifiers. Recent literature suggests that a series of inflammatory processes may be involved in initiating and propagating OA. We hypothesized that products of neutrophils and macrophages, namely myeloperoxidase (MPO), a specific enzyme responsible for the production of both highly reactive hypochlorous acid (HOCl) and chlorine gas (Cl2) and chlorinated peptides, may be present in the synovial fluid of patients with OA. We examined the synovial fluid from 30 patients to identify and profile the presence of MPO. We divided the samples into three groups using radiographic and clinical assessment: (1) control, patients with acute knee injury with no history of OA and no radiographic evidence of OA; (2) early OA, patients with a mild OA based on radiographs; and (3) late OA, patients with a longstanding history of OA and with radiographic evidence of complete joint loss. Patients with early OA demonstrated significantly elevated levels of MPO. We also demonstrated the presence of HOCl and Cl2 modified proteins (Cl-peptides) in early OA synovial fluid samples by liquid chromatography and mass spectrometry. Patients in the control and advanced OA groups demonstrated little elevation in MPO levels and Cl-peptides were undetectable. These results indicate that MPO and Cl-peptides may serve as diagnostic markers for the detection of early OA. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1128,1135, 2007 [source]


The entrapment of corrosion products from CoCr implant alloys in the deposits of calcium phosphate: A comparison of serum, synovial fluid, albumin, EDTA, and water

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 8 2006
A. C. Lewis
Abstract Physical wear of orthopedic implants is inevitable. CoCr alloy samples, typically used in joint reconstruction, corrode rapidly after removal of the protective oxide layer. The behavior of CoCr pellets immersed in human serum, foetal bovine serum (FBS), synovial fluid, albumin in phosphate-buffered saline (PBS), EDTA in PBS, and water were studied using X-ray Photoelectron Spectroscopy (XPS) and Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS). The difference in the corrosive nature of human serum, water, albumin in PBS and synovial fluid after 5 days of immersion was highlighted by the oxide layer, which was respectively 15, 3.5, 1.5, and 1.5 nm thick. The thickness of an additional calcium phosphate deposit from human serum and synovial fluid was 40 and 2 nm, respectively. Co and Cr ions migrated from the bulk metal surface and were trapped in this deposit by the phosphate anion. This may account for the composition of wear debris from CoCr orthopedic implants, which is known to consist predominantly of hydroxy-phosphate compounds. Known components of synovial fluid including proteoglycans, pyrophosphates, phospholipids, lubricin, and superficial zone protein (SZP), have been identified as possible causes for the lack of significant calcium phosphate deposition in this environment. Circulation of these compounds around the whole implant may inhibit calcium phosphate deposition. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 24:1587,1596, 2006 [source]


An adenosine A2A receptor agonist reduces interleukin-8 expression and glycosaminoglycan loss following septic arthrosis,

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2005
Steven B. Cohen
Abstract The purpose of this study was to determine whether an adenosine A2A receptor agonist (ATL146e) might augment the current treatment regimen of antibiotics plus irrigation and debridement to prevent the arthritic effects associated with joint sepsis. Staphylococcus aureus bacteria were injected into knees of rabbits, which were divided into 4 treatment groups (12 rabbits per group): no treatment, ATL146e only, antibiotics only, or antibiotics plus ATL146e. Analysis at days 1, 3, and 7 consisted of gross joint appearance, synovial fluid, serum, histologic, immunohistochemical, and biochemical analysis. Synovial fluid cultures at day 7 were negative in all antibiotic and antibiotic plus ATL146e treated knees indicating clearance of bacteria. Average WBC counts from synovial fluid aspirates significantly decreased with treatment of antibiotics alone and antibiotics plus ATL146e. Treatment with antibiotics plus ATL146e significantly decreased the Interleukin-8 content when compared to other treatment groups (p < 0.001) indicating inflammatory response suppression. Histologic grading resulted in notably improved scores in the antibiotics plus ATL146e group compared to other treatment groups (p < 0.001). Glycosaminoglycan assay values were significantly greater in the ATL146e plus antibiotics group compared to the untreated control group (p < 0.04) indicating chondroprotection. The results of this study indicate that administration of an adenosine A2A agonist in combination with antibiotic therapy diminishes joint WBC chemotaxis and reduces joint inflammation, while not compromising the clearance of intraarticular bacteria in a rabbit model. Early bacterial clearance with modulation of the inflammatory response appears to prevent the early degradative effects of joint sepsis. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]


Repeated intraarticular injections of triamcinolone acetonide alter cartilage matrix metabolism measured by biomarkers in synovial fluid

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2005
Christophe Céleste
Abstract Although intraarticular (IA) corticosteroids are frequently used to treat joint disease, the effects of their repeated use on articular cartilage remains controversial. The aim of our study was to determine the effects of a clinically recommended dose of IA triamcinolone acetonide (TA), on synovial fluid (SF) biomarkers of cartilage metabolism. Ten adult horses, free of osteoarthritis (OA) in their radiocarpal joints, were studied. One radiocarpal joint of each horse was randomly chosen for treatment and the contralateral anatomically paired joint acted as the control. Aseptic arthrocentesis was performed weekly on both joints for 13 weeks. The initial results from the first 3 weeks of the experimental period established baseline untreated control marker levels for each joint, each being its own control. On weeks 3, 5, and 7, a sterile suspension of 12mg of TA was injected into the treated joint and an equivalent volume of sterile saline solution (0.9%) was injected into the control joint. SF was immunoassayed for biomarkers of aggrecan turnover (CS 846 & KS), types I and II collagen cleavage (C1,2C) and type II collagen synthesis (CPII). In treated joints, there was a significant increase in CS 846, KS, C1,2C and CPII epitope concentrations following IA TA injections when compared to baseline levels. There was also a significant increase in C1,2C and CPII epitope concentrations in the contralateral control joints following IA TA injections in the treated joint. Significant differences were observed between treated and control joints for all markers except CPII. These findings indicate that TA alters articular cartilage and collagen metabolism in treated and, interestingly, also in control joints, suggesting a systemic effect of the drug. Though intuitively the observed findings would favor the hypothesis that long-term IA TA treatment changes joint metabolism and this may have detrimental effects; further studies would be necessary to confirm this. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]


Expression of the CD44 variant isoform 5 in the human osteoarthritic knee joint: Correlation with radiological, histomorphological, and biochemical parameters

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2004
Susanne Fuchs
Abstract Purpose: The purpose of this study was to correlate expression of CD44v5 in osteoarthritic synovium, cartilage, and synovial fluid with radiographical, histomorphological, and biochemical data. Methods: Cartilage and synovia specimens of 27 patients with osteoarthritis were histomorphologically assessed according to Mankin and Pelletier, respectively. Extended weight-bearing antero-posterior radiographs were evaluated according to Kellgren and Ahlback. Expression of membrane-bound CD44v5 was analyzed by immunohistochemistry and levels of soluble CD44v5 were determined by ELISA. Results: Expression of CD44v5 in cartilage and synovia was detected in 67% and 59% of the patients, respectively. Immunohistochemical findings in cartilage correlated significantly with structural cartilage changes (p < 0.001), whereas no correlation was found between expression in synovia and inflammatory synovial changes. Additionally, no relationship was evident between CD44v5 expression and radiographical data, but expression in cartilage and synovium was significantly correlated with each other (p < 0.04). Surprisingly, expression of CD44v5 in both cartilage and synovia was negatively correlated with synovial fluid levels of TNF, (p < 0.03 and p < 0.02, respectively), and no association was evident with levels of IL-1,. Conclusions: The data demonstrate expression of CD44v5 in osteoarthritic cartilage and synovia, probably independent of joint inflammation. But more importantly, expression of this receptor variant in cartilage seems to be strongly related to the degree of cartilage destruction. © 2003 Published by Elsevier Ltd. on behalf of Orthopaedic Research Society. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]


Amelioration of disease severity by intraarticular hylan therapy in bilateral canine osteoarthritis

JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 3 2000
K. W. Marshall
Because of its high molecular weight, the glycosaminoglycan molecule hyaluronan is responsible for the viscoelastic properties of normal synovial fluid. In osteoarthritis, the concentration and molecular weight of hyaluronan in synovial fluid is diminished; this impairs the ability of synovial fluid to effectively lubricate joints, absorb loads, and exert anti-inflammatory effects. Using a bilateral anterior cruciateligament transection and partial neurectomy canine model of osteoarthritis, this study examined the effect of viscosupplementation with hylan G-F 20 as a treatment for osteoarthritis, this study examined the effect of viscosupplementation with hylan G-F 20 as a treatment for osteoarthritis. Twelve dogs underwent bilateral arthroscopic anterior cruciate-ligament transections and partial neurectomy of the knee joints. Beginning 1 week after the operation, six dogs received three weekly 500-,l injections of hylan G-F 20 in one knee and a sham injection of saline solution in the contralateral knee (early-treatment group). The remaining six animals underwent the same treatment 2 months following the procedure (late-treatment group). All dogs were killed at 8 months, and both knees were evaluated for gross pathology, histology, and proteoglycan content. In addition, with use of 500-MHz [1H] magnetic resonance spectroscopy, the synovial fluid from both knees was assessed for changes in metabolic profile. Differences in outcome were analyzed with paired t tests. Gross pathological and histological examination revealed significantly less severe changes of osteoarthritis in knees treated with hylan G-F 20 2 months after surgery than in the contralateral untreated knees. Magnetic resonance spectroscopy of the specimens in this late-treatment group showed significantly decreased glucose concentrations and significantly elevated isoleucine levels in the synovial fluid from knees treated with hylan G-F 20 compared with the controls. Previous magnetic resonance spectroscopy had shown that glucose concentrations increase with the onset of osteoarthritis and eventually diminish in end-stage osteoarthritis. The three injections of hylan were given after osteoarthritis was established, and the severity of the disease was ameliorated in the treated knees 6 months after treatment. This occurred although hylan G-F 20 is almost certainly cleared from joints by lymphatics within 4 weeks of injection, suggesting that hylan therapy can retard the progression of osteoarthritis for periods of time extending beyond the intraarticular residence time of the injected molecules and that hylan injections given at relatively early stages of osteoarthritis may have a chondroprotective effect. No changes in outcome were noted in the animals that received hylan G-F 20 immediately following surgery. [source]


Pharmacokinetics of intravenous ceftiofur sodium and concentration in body fluids of foals

JOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2009
S. MEYER
The objectives of this study were to determine pharmacokinetics of intravenous (i.v.) ceftiofur in foals, to compare ultra-high performance liquid chromatography tandem mass spectometry (UPLC-MS/MS) and microbiologic assay for the measurement of ceftiofur concentrations, and to determine the minimum inhibitory concentration (MIC) of ceftiofur against common equine bacterial pathogens. In a cross-over design, ceftiofur sodium was administered i.v. to six foals (1,2 days-of-age and 4,5 weeks-of-age) at dosages of 5 and 10 mg/kg. Subsequently, five doses of ceftiofur were administered i.v. to six additional foals between 1 and 5 days of age at a dose of 5 mg/kg q 12 h. Concentrations of desfuroylceftiofur acetamide (DCA), the acetamide derivative of ceftiofur and desfuroylceftiofur-related metabolites were measured in plasma, synovial fluid, urine, and CSF by use of UPLC-MS/MS. A microbiologic assay was used to measure ceftiofur activity for a subset of plasma samples. Following i.v. administration of ceftiofur at a dose of 5 mg/kg to 1,2 day-old foals, DCA had a t˝ of 7.8 ± 0.1 h, a body clearance of 74.4 ± 8.4 mL/h/kg, and an apparent volume of distribution of 0.83 ± 0.09 L/kg. After multiple i.v. doses at 5 mg/kg, DCA concentrations in CSF were significantly lower than concurrent plasma concentrations. Ceftiofur activity using a microbiologic assay significantly underestimated plasma concentrations of DCA. The MIC of ceftiofur required to inhibit growth of 90% of isolates of Escherichia coli, Pasteurella spp, Klebsiella spp, and ,-hemolytic streptococci was <0.5 ,g/mL. Intravenous administration of ceftiofur sodium at the rate of 5 mg/kg every 12 h would provide sufficient coverage for the treatment of susceptible bacterial isolates. [source]


Pharmacokinetics of oral doxycycline and concentrations in body fluids and bronchoalveolar cells of foals

JOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 3 2007
A. WOMBLE
The objective of this study was to determine the disposition of orally administered doxycycline in foals. Six healthy 4- to 8-week-old foals were used. Doxycycline was administered to each foal via the intragastric (IG) route at dosages of 10 and 20 mg/kg, in a cross-over design. After the first 10 mg/kg dose, five additional doses were administered at 12-h intervals. A microbiological assay was used to measure doxycycline activity in serum, urine, peritoneal fluid, synovial fluid, cerebrospinal (CSF), pulmonary epithelial lining fluid (PELF), and bronchoalveolar (BAL) cells. Following administration at 10 mg/kg, mean ± SD time to peak serum doxycycline activity (tmax) was 3.0 ± 1.2 h, maximum serum activity (Cmax) was 2.54 ± 0.27 ,g/mL, and terminal half-life (t1/2) was 8.5 ± 2.8 h. Administration at a dose of 20 mg/kg resulted in a significantly longer tmax (5.5 ± 1.8 h) as well as a tendency toward higher Cmax (2.89 ± 0.33 ,g/mL) and longer t1/2 (11.9 ± 2.6 h). After multiple IG doses, doxycycline activity in CSF was significantly lower than concurrent serum activity, whereas peritoneal fluid, synovial fluid, and BAL cell doxycycline activity was similar to concurrent serum activity. Doxycycline activity in urine and PELF was significantly higher than that found at other sites. Oral administration at a dosage of 10 mg/kg every 12 h would maintain serum, PELF, and BAL cell activity above the minimum inhibitory concentrations of Rhodococcus equi, , -hemolytic streptococci, and other susceptible bacterial pathogens for the entire dosing interval. [source]


Pharmacokinetics of amoxycillin in normal horses and horses with experimental arthritis

JOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 1 2001
J. O. Errecalde
The serum and synovial pharmacokinetics of amoxycillin (AMX) were studied after i.v. administration at a dosage of 40 mg/kg to normal horses and horses with induced aseptic carpal arthritis. The best estimates of serum and synovial pharmacokinetic parameters were calculated by mono or bivariable non-linear regression analysis. A biexponential equation was used to describe the concentration vs. time profiles in both normal and arthritic horses. There were no serum kinetic differences between normal and arthritic horses. There were, however, major synovial kinetic changes between these groups. The rate of penetration from serum to synovial fluid was larger in arthritic animals, indicating better penetration in this case. On the other hand, the rate of disappearance from synovial fluid was larger in normal horses, indicating more persistence of the drug in the diseased joint. Synovial AMX availability increased from 21% in normal horses to 79% in arthritic horses. These findings support the use of AMX for the treatment of infectious synovial joint disease produced by susceptible organisms in horses. [source]


Synovial fluid at microwave frequencies

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 7 2007
Anil Lonappan
Abstract Arthritis is one of the most pervasive diseases that causes of disability. For most people arthritis pain and inflammation cannot be avoided as the body ages. The present communication reports the study on the synovial fluid has the main lubricant in joints collected from normal persons and those ailing from arthritis are subjected to the microwave study and the variations of the dielectric parameters are investigated. The in vitro measurements of synovial fluid samples are done using cavity perturbation technique in the frequency range of 2,3 GHz. It is observed that in this band, the dielectric constant of normal samples are higher than those of arthritis affected ones and conductivity of is higher in normal samples, which finds application in detecting arthritis using microwaves. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1700,1702, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22552 [source]


Hydration and health: a review

NUTRITION BULLETIN, Issue 1 2010
B. Benelam
Summary Water is essential for life and maintaining optimal levels of hydration is important for humans to function well. Water makes up a large proportion of our body weight (60% on average), distributed between the intracellular (inside cells) and extracellular (water in the blood and in between cells) compartments. Water is the major component of body fluids, such as blood, synovial fluid (fluid in the joints), saliva and urine, which perform vital functions in the body. The concentration of solutes (osmolality) in body fluids is closely controlled, and even very small changes in osmolality trigger a physiological response; either to increase body water by reducing urinary output and stimulating thirst; or to excrete excess water as urine. Generally, body water is maintained within narrow limits. However, if water losses are not sufficiently replaced, dehydration occurs. Extreme dehydration is very serious and can be fatal. More mild dehydration (about 2% loss of body weight) can result in headaches, fatigue and reduced physical and mental performance. It is also possible to consume too much water and in rare cases this can result in hyponatraemia (low levels of sodium in the blood). We can get water from almost all drinks and from some foods in the diet. Food provides about 20% on average and this could vary widely depending on the types of food chosen. We also get water from all the drinks we consume, with the exception of stronger alcoholic drinks like wines and spirits. All these can contribute to dietary water, but also have other effects on health both positive and negative. The major concerns with regards to beverages are their energy content and their effect on dental health. With obesity levels continuing to increase it is important for many in the population to control their energy intake, and drinks as well as foods must be considered for their energy content. With regards to dental health, there are two concerns; dental caries and dental erosion. Dental caries are caused by a reduction in pH due to bacterial fermentation of carbohydrates, and so the frequency of consumption of drinks containing sugars is a concern for risk of caries. Dental erosion occurs at a lower pH and is caused by the consumption of acidic foods and drinks, in particular, citrus juices and soft drinks containing acids. Individual water needs vary widely depending on many factors including body size and composition, the environment and levels of physical activity. Thus it is very difficult to make generic recommendations about the amount of water to consume. The FSA currently recommends drinking about 1.2 litres per day (about 6,8 glasses). [source]


Septic arthritis in patients followed-up in neonatal intensive care unit

PEDIATRICS INTERNATIONAL, Issue 6 2002
Sevki Kabak
Abstract Background: Septic arthritis is an uncommon, but serious disorder in neonates. Most patients survive with permanent handicaps. Due to the rarity of this condition in neonates and paucity of signs and symptoms, the diagnosis of septic arthritis in newborns is more difficult than in older children. Methods: Septic arthritis or suppurative arthritis is an infection of the joint by a variety of microorganisms, including bacteria, viruses, mycobacteria and fungi. Purulent synovial fluid, positive culture and positive Gram stain were accepted as a gold standard for exact diagnosis. Fourteen neonates who were followed-up in a neonatal intensive care unit, with septic arthritis, were included in a study based on a review of medical reports and a long-term clinical and radiological follow-up. Clinical symptoms, bacteriology, risk factors and outcomes are discussed. Results: Staphylococcus aureus was the predominant causative organism. Risk factors for septic arthritis were prematurity (4/14), umbilical catheterization or venous catheterization (3/14), sepsis (3/14), perinatal asphyxia (2/14) and difficult birth (1/14). All cases of septic arthritis in neonates were improved without squealae except in two patients. One patient died and one patient had severe squealae. In these two patients, the duration of disease from clinical onset to initiation of therapy was long. Conclusion: The most important prognostic factor in predicting a favorable outcome in neonatal septic arthritis is early diagnosis and therapy. When appropriate treatment is delayed, catastrophic sequelae are inevitable. Early diagnosis of the condition and rapid removal of pus are mandatory for the survival of the joint. Long-term follow-up may reveal effects of epiphyseal damage, early degenerative changes and limitation of the range of motion. [source]