Calcium Crystals Research Articles

Electrolyte Imbalances and Nephrocalcinosis in Acute Phosphate Poisoning on Chronic Type 1 Renal Tubular Acidosis due to Sjögren's Syndrome

Although renal calcium crystal deposits (nephrocalcinosis) may occur in acute phosphate poisoning as well as type 1 renal tubular acidosis (RTA), hyperphosphatemic hypocalcemia is common in the former while normocalcemic hypokalemia is typical in the latter. Here, as a unique coexistence of these two seperated clinical entities, we report a 30-yr-old woman presenting with carpal spasm related to hypocalcemia (ionized calcium of 1.90 mM/L) due to acute phosphate poisoning after oral sodium phosphate bowel preparation, which resolved rapidly after calcium gluconate intravenously. Subsequently, type 1 RTA due to Sjögren's syndrome was unveiled by sustained hypokalemia (3.3 to 3.4 mEq/L), persistent alkaline urine pH (> 6.0) despite metabolic acidosis, and medullary nephrocalcinosis. Through this case report, the differential points of nephrocalcinosis and electrolyte imbalances between them are discussed, and focused more on diagnostic tests and managements of type 1 RTA.

Retropharyngeal Calcific Tendinitis Mimicking a Retropharyngeal Phlegmon

Background. Acute retropharyngeal tendinitis is a little known but not an uncommon condition. It was first described by Hartley in 1964 as an inflammation of the longus colli muscle secondary to calcium crystals deposition on its insertion. The calcifications are mostly located on the oblique portion of the muscle at the level of C1-C2. Methods. We will describe this disease through 4 cases that presented in our institution. Results. The most common symptoms are severe neck pain, odynophagia, and a painful restriction of neck movement. It is associated with mild fever and inflammatory lab findings such as a slight elevation of white blood cell count, erythrocyte sedimentation rate, and C-reactive protein. CT scan is recommended as the first-line imaging modality to establish a diagnosis. Treatments consist of NSAIDs and analgesics to accelerate the healing process. If symptoms are severe, a course of corticosteroids is required. Conclusion. Since the clinical and laboratory findings of this condition and those of a retropharyngeal abscess overlap, it is important to establish the right diagnosis in order to prevent more invasive procedures. A good knowledge of this clinical entity by otolaryngologists would prevent delays in hospital discharge and unnecessary anxiety.

Phosphocitrate Is Potentially a Disease-Modifying Drug for Noncrystal-Associated Osteoarthritis

Phosphocitrate (PC), a calcification inhibitor, inhibits the development of crystal-associated osteoarthritis (OA) in Hartley guinea pigs. However, the molecular mechanisms underlying its disease-modifying effect remain elusive. This study sought to test the hypothesis that PC has calcium crystal-independent biological activities which are, at least in part, responsible for its disease-modifying activity. We found that PC inhibited the proliferation of OA fibroblast-like synoviocytes in the absence of calcium crystals. Consistent with its effect on cell proliferation, PC downregulated the expression of numerous genes classified in cell proliferation. PC also downregulated the expression of many genes classified in angiogenesis and inflammatory response including prostaglandin-endoperoxide synthase 2, interleukin-1 receptor, type I, and chemokine (C-C motif) ligand 2. In contrast, PC upregulated the expression of many genes classified in musculoskeletal tissue development, including aggrecan, type I collagen, and insulin-like growth factor binding protein 5. These findings suggest that PC is not only a promising disease-modifying drug for crystal-associated OA but also for noncrystal-associated OA.

Biological Activities of Phosphocitrate: A Potential Meniscal Protective Agent

Phosphocitrate (PC) inhibited meniscal calcification and the development of calcium crystal-associated osteoarthritis (OA) in Hartley guinea pigs. However, the mechanisms remain elusive. This study sought to examine the biological activities of PC in the absence of calcium crystals and test the hypothesis that PC is potentially a meniscal protective agent. We found that PC downregulated the expression of many genes classified in cell proliferation, ossification, prostaglandin metabolic process, and wound healing, including bloom syndrome RecQ helicase-like, cell division cycle 7 homolog, cell division cycle 25 homolog C, ankylosis progressive homolog, prostaglandin-endoperoxide synthases-1/cyclooxygenase-1, and plasminogen activator urokinase receptor. In contrast, PC stimulated the expression of many genes classified in fibroblast growth factor receptor signaling pathway, collagen fibril organization, and extracellular structure organization, including fibroblast growth factor 7, collagen type I, alpha 1, and collagen type XI, alpha 1. Consistent with its effect on the expression of genes classified in cell proliferation, collagen fibril organization, and ossification, PC inhibited the proliferation of OA meniscal cells and meniscal cell-mediated calcification while stimulating the production of collagens. These findings indicate that PC is potentially a meniscal-protective agent and a disease-modifying drug for arthritis associated with severe meniscal degeneration.

The progressive ankylosis gene product ANK regulates extracellular ATP levels in primary articular chondrocytes

IntroductionExtracellular ATP (eATP) is released by articular chondrocytes under physiological and pathological conditions. High eATP levels cause pathologic calcification, damage cartilage, and mediate pain. We recently showed that stable over-expression of the progressive ankylosis gene product, ANK, increased chondrocyte eATP levels, but the mechanisms of this effect remained unexplored. The purpose of this work was to further investigate mechanisms of eATP efflux in primary articular chondrocytes and to better define the role of ANK in this process.MethodsWe measured eATP levels using a bioluminescence-based assay in adult porcine articular chondrocyte media with or without a 10 minute exposure to hypotonic stress. siRNAs for known ATP membrane transporters and pharmacologic inhibitors of ATP egress pathways were used to identify participants involved in chondrocyte eATP release.ResultseATP levels increased after exposure to hypotonic media in a calcium-dependent manner in monolayer and 3-dimensional agarose gel cultures (p < 0.001). A potent transient receptor potential vanilloid 4 (TRPV4) agonist mimicked the effects of hypotonic media. ANK siRNA suppressed basal (p < 0.01) and hypotonically-stressed (p < 0.001) ATP levels. This effect was not mediated by altered extracellular pyrophosphate (ePPi) levels, and was mimicked by the ANK inhibitor, probenecid (p < 0.001). The P2X7/4 receptor inhibitor Brilliant Blue G also suppressed eATP efflux induced by hypotonic media (p < 0.001), while ivermectin, a P2X4 receptor stimulant, increased eATP levels (p < 0.001). Pharmacologic inhibitors of hemichannels, maxianion channels and other volume-sensitive eATP efflux pathways did not suppress eATP levels.ConclusionsThese findings implicate ANK and P2X7/4 receptors in chondrocyte eATP efflux. Understanding the mechanisms of eATP efflux may result in novel therapies for calcium crystal arthritis and osteoarthritis.

Epigallocatechin-3-gallate reduces inflammation induced by calcium pyrophosphate crystals in vitro

Although osteoarthritis (OA) is defined as a cartilage disease, synovitis involving mononuclear cell infiltration and overexpression of proinflammatory mediators is common in early and late OA. Calcium crystals deposition is thought to be a factor that likely contributes to synovial inflammation. In recent years, significant interest has emerged in the beneficial health effects attributed to the green tea polyphenols and in particular to epigallocatechin-3-gallate (EGCG). It has been demonstrated that some of the actions of EGCG are linked to its ability to interfere with cell membranes. The objective of this study was to evaluate the influence of EGCG in some inflammatory aspects of OA and whether EGCG is able to interfere with membrane organization. We assessed the effect of EGCG on the production of proinflammatory cytokines and chemokines released by human fibroblast-like synoviocytes (FLS) and THP-1 cells stimulated with calcium pyrophosphate (CPP) crystals in presence of methyl-β-cyclodextrin (MβCD), a cholesterol-removing agent that disturbs lipid raft structures. The chemotactic effect of culture supernatants was also evaluated. EGCG inhibited interleukin (IL)-1β, transforming growth factor beta, IL-8, and chemokine (C–C motif) ligand 2 (CCL2) release by stimulated FLS and/or THP-1 cells in a dose-dependent manner. Supernatants of CPP-stimulated cells induced the migration of neutrophils and mononuclear cells which decreased in a dose-dependent manner in the presence of EGCG. EGCG increased cell viability when added to THP-1 cells treated with MβCD. Furthermore, MβCD enhanced the inflammatory response to CPP crystals increasing IL-8 and CCL2 secretion which was inhibited by EGCG in a dose-dependent manner. This study showed that EGCG is able to reduce the inflammatory response induced by CPP crystals in vitro. The identification of EGCG as dietary supplement capable of affording protection or modulating the inflammatory response to CPP crystals may have important implications in the prevention and treatment of OA and crystal-related arthropathies.

Arthropathies du rhumatisme à pyrophosphate de calcium (PPCa)

Calcium pyrophosphate deposition disease is a metabolic arthropathy caused by the deposition of calcium pyrophosphate (CPP) in and around joints, following or sometimes preceding cartilage calcification (chondrocalcinosis) which can be frequently observed in the cervical spine (70%) – including the craniocervical junction (tissues about the odontoid process), cervical intervertebral disks, facet joints, spinal ligaments and bursae – and in the temporomandibular joint. Deposition of calcium crystals is often a silent process. There is a variable constellation of signs and symptoms linked to this type of crystalline arthropathy, usually of acute onset (cervicalgia, neck stiffness, fever), sometimes of progressive onset (radiculalgia, cervical myelopathy) simulating a wide array of diseases (meningitis, infectious spondylitis, inflammatory. rheumatism, vertebral tumors): rheumatologists must be aware of its protean appearance on imaging (essentially computed tomography) and need to discuss the relationship between spinal alterations and symptoms, in order to avoid misdiagnoses and incorrect management.

John Anthony Clark Wilson

<h3>Background</h3> The role and the significance of calcium crystals (CC) in synovial inflammation and in Osteoarthritis (OA) progression is somewhat debated. Calcium pyrophosphate (CPP) and basic calcium phosphate (BCP) are...

Dynamics of scale regeneration in seawater- and brackish water-acclimated sea bass, Dicentrarchus labrax

Scale loss is a common occurrence in both wild fish and those in aquaculture production systems, and regeneration of scales has been described in several freshwater species. Relatively little information exists about this process in marine fish, and in the present study, the chronology of scale regeneration was characterized in juvenile sea bass Dicentrarchus labrax, maintained in full seawater (SW; 36‰, 11.2 mM Ca(2+)) or brackish water (BW; 3.5‰, 1.1 mM Ca(2+)). Despite the significant differences in plasma osmolality, plasma calcium (Ca) and phosphorus (P) were similar between SW and BW. Removal of scales (2.25 cm(2)) did not modify plasma osmolality but a significant reduction in plasma Ca occurred in sea bass in BW during early phases of scale regeneration. Scale Ca and P contents changed during regeneration in SW and BW fish, and in fully regenerated scales, their concentration was comparable to ontogenic scales which had a Ca/P ratio around 1.0. Regenerating scales were first visible at 3 days after removal, and by 6 days, the descaled area was covered with new scales in both SW and BW fish. From this stage onwards, while scale area and mass rose gradually, a rapid accretion of calcium crystals was observed over the basal plate, especially in SW, and Ca and P content per scale increased at a very high rate, decreasing only at the later stages, and between 21 and 30 days the newly formed scales had already ontogenic-like morphometric features. Scale tartrate-resistant acid phosphatase (TRAP) or alkaline phosphatase (ALP) activity was initially similar in SW and BW. However, during regeneration, TRAP was significantly higher in scales of sea bass in SW compared to those in BW where ALP predominated; these differences persisted at 30 days.

In vitro effect of Hordeum vulgare on the crystallization of calcium oxalate monohydrate (whewellite)

The recommended conservative treatment of hyperoxaluria is mainly based on hyperhydration and ingestion of inhibitors of crystallization. In accordance with this context, the aim of this study was to determine the in vitro effect of Hordeum vulgare on calcium oxalate crystallization oxalo-dependent. The crystallization of calcium oxalate monohydrate in supersaturated aqueous solution at 37 °C, was followed in a model turbidimetric continuous in a closed system. The proposed model is very good reproducibility (CV < 10%), crystallization was monitored continuously in the presence of Hordeum vulgare at different concentrations (0.0625 to 1 g/L). The comparison of turbidimetric parameters, that characterize the growth stage of monohydrated oxalate calcium crystals and observation of the crystals obtained at the end of crystallization into scanning electron microscopy, have been able to demonstrate the inducing effect of Hordeum vulgare to 0.0625 g/L and a slight inhibitory effect at the others concentrations.

Calcinose cutânea distrófica em adolescente: relato de caso

Calcinose cutânea é a precipitação de cristais de cálcio na pele. Pode ser dividida em quatro categorias: distrófica, metastática, iatrogênica e idiopática. A forma distrófica é a mais comum, com níveis séricos normais de cálcio e de fósforo. Relatamos caso de calcinose cutânea distrófica localizada e assintomática no joelho direito de um adolescente. Os exames clínico e laboratorias revelaram telangectasias periungueais e fator antinuclear positivo (títulomaior que 1/1280 de padrão nucleolar), o que sugere a associação da calcinose cutânea com uma colagenose

Bovine osteoblasts cultured on polyanionic collagen scaffolds: An ultrastructural and immunocytochemical study

Collagen is the most abundant protein in the body and is also the most important component of the extracellular matrix. Collagen has several advantages as a biomaterial such as lack of toxicity, biocompatibility, biodegradability, and easy reabsorption. In this study, we examined bovine osteoblasts cultured on native or anionic collagen scaffolds prepared from bovine pericardium after selective hydrolysis of glutamine and asparagine side chain amides for periods from 24 (BP24) and 48 h (BP48). The cells were cultured in control and mineralization medium at 37 °C in the presence of 5% CO(2). Transmission and scanning electron microscopy, energy dispersive spectroscopy, and an immunocytochemical marker were used for analysis. Cells with an irregular morphology forming a confluent multilayer were observed on matrices kept in control medium. Most of these cells presented a polygonal or elongated flattened morphology. Several spherical deposits of calcium crystal associated with phosphorus were observed on the native and BP48 matrices. Similar results were observed in samples kept in control medium except with lower calcium/phosphorus ratio. Vesicles actively expelled from the cell membrane were also seen (do this vesicles corresponds to calcium/phosphorus deposits). Osteocalcin was clearly visible on matrices kept in mineralization medium and was more expression on the surface of BP48 matrices. The results showed that anionic collagen is able to support osteoblastic differentiation, regardless of the medium used. Finally, the BP48 matrix promoted better osteoblast differentiation than the native matrix.

Response to 'Plasma proteins present in osteoarthritic synovial fluid can stimulate cytokine production via Toll-like receptor 4' - authors' reply

We thank Oliviero and colleagues for their interest in our recent publication [1] and for reporting their very interesting related experiments [2]. Th eir results strongly support the concept that extravascular plasma proteins may act as damage-associated molecular patterns, and specifi cally as Toll-like receptor 4 agonists. In addition, we note that the NALP-3 infl ammasome exhibits dependence on Toll-like receptor 4 or other mechanisms of priming of IL-1β transcription, thereby generating pro-IL-1β that can be converted to IL-1β by the activated infl ammasome [3]. Although biochemical measurement of plasma and serum were not performed, we suspect the enhanced eff ect of serum compared with plasma could be related to mediators generated in the clotting process or released by platelets during the clotting process (but not released in the generation of plasma) and not related to the removal of fi brinogen. Th e observation that fi brinogen is itself able to prime the response to calcium crystalinduced infl ammation further supports the role of fi brino gen as a Toll-like receptor 4 agonist [4,5], as demon strated by its ability to prime the infl ammasome for response to activation by calcium crystals. We thank Oliviero and colleagues for sharing their results and look forward to future studies elucidating the potentially critical role of plasma proteins as extravascular damage-associated molecular patterns.

ANTIINFLAMMATORY PROPERTIES OF PEPTIDE COMPLEX OBTAINED FROM THE COD LIVER (GADIDAE) ON THE MODEL OF ADJUVANT ARTHRITIS IN THE RAT

s. PHYTOPHARM 2012 M 94 Obzory po kliniceskoj farmacologii i lekarstvennoj terapii [Reviews of clinical pharmacology and drug therapy] ТОМ 10/2012/2 exist due to relatively high content of ferulic acid in sugar beet fibres (Table 1). Most of the phenolic substances in the additives were found in nonextractable fractions, which have been shown to possess significantly higher antioxidant activity than extractable fractions (Table 2). The obtained results suggest the possibility for upgrading the functionality of meat products with incorporated NTf and Tf additives, which is in line with the basic concept of ChANCE. RESEARCHES ON TANNINS CONTAINING MEDICINAL VEGETATIVE RAW MATERIALS STANDARDIZATION © Samylina I. A., Grinko E. N. Table 2. Antioxidant activity of extractable and nonextractable fractions, expressed as iC 50 (g sample/ml), (M ± m) CAf Tf NTR dPPh activity of extractable fraction 0.89 ± 0.11 1.93 ± 0.52 1.12 ± 0.18 dPPh activity of nonextractable fraction 0.02 ± 0.01 0.14 ± 0.01 0.07 ± 0.01 AOA activity of extractable fraction 2.45 ± 0.15 4.84 ± 0.69 3.21 ± 0.36 AOA activity of nonextractable fraction 0.80 ± 0.32 0.59 ± 0.06 0.34 ± 0.07 Reducing activity of extractable fraction 0.27 ± 0.01 1.01 ± 0.06 0.48 ± 0.01 Reducing activity of nonextractable fraction 0.03 ± 0.01 0.13 ± 0.01 0.06 ± 0.01 Chelating activity of extractable fraction 0.22 ± 0.07 0.47 ± 0.20 1.24 ± 0.19 Chelating activity of nonextractable fraction 0.29 ± 0.05 0.18 ± 0.06 1.13 ± 0.09 Means in each row followed by the same superscript are not significantly different, P < 0.05 First Moscow State Medical University I. M. Sechenov, Moscow, Russia Objective of the study was standartisation of medicinal vegetative raw material (MVRM) containing tannins. The objects of research were oak and viburnum bark; bistort, bergenia, tormentil and sanguisorba rhizomes; bilberry, bird cherry and alder fruit; sumag and smoke tree leaf. The microscopic, chromotographic, UV-, infraredand Raman-spectro-scopic characteristics of plant material were done. Tannins were determined by hPlC, UV-spectroscopy, potentiometric titration. The possibility of collagen 1 % solutions application as a tannins sedimentation reagent was investigated. The quantitative method of the tannins definition in plants material was developed and patented. UV-, infraredand Raman-spectroscopic characteristics for 11 types of MVRM and 8 standard samples (glucose, starch, fructose, tannin, pyrogallol, gallic and ellagic acids, rutine) were recorded and described. The spectra are recommended for identification of powders of raw materials. We’ve studied the diagnostic signs variability of MVRM at crushing. The anatomic and diagnostic signs of crushed and powdered raw materials were specified. The most variability elements (bunches and their parts, mechanical fibers, the oxalate calcium crystals chains; conglomerates of stony cages and fibers) were revealed and described: and also the signs, allowing to identify powders of similar types of raw materials.

A complex case of fatal calciphylaxis in a female patient with hyperparathyroidism secondary to end stage renal disease of graft and coexistence of haemolytic uremic syndrome

Calciphylaxis is a potentially fatal complication of persistent secondary hyperparathyroidism; its cause is still not clear. Unfortunately there is no close relation in severity of clinical picture, serological and pathological alteration. For this reason the prognosis is difficult to establish. Administration of sodium thiosulphate may reduce the precipitation of calcium crystals and improve the general clinical conditions before surgical parathyroidectomy, which seems the only therapeutic approach able to reduce the mortality risk in these patients. A 60 year old female patient suffering from End Renal Stage Disease, on haemodialysis from 2001 due to the onset of haemolytic uremic syndrome, underwent a kidney transplant in April 2008. After transplantation there was a recurrence of the haemolytic uremic syndrome, with temporary worsening of the graft. Six months later there was a definite loss of graft and return to dialysis treatment. On April 2010 a severe systemic calciphylaxis related to secondary hyperparathyroidism was diagnosed. The patient underwent parathyroidectomy but, because of the unimproved clinical picture, treatment with sodium thiosulphate was initiated. There was only improvement in cutaneous lesions. The worsening general clinical condition of the patient caused death due to general septic complications. The coexistence of haemolytic uremic syndrome and secondary hyperpathyroidism makes the prognosis poor and, in this case, therapy, which counteracts calcium crystals precipitation, has no effect. Preventive parathyroidectomy can be considered as the only possible treatment.

2073 DIETARY HYDROXYPROLINE INDUCES NEPHROLITHIASIS IN THE ADULT PORCINE MODEL

You have accessJournal of UrologyStone Disease: Basic Research I1 Apr 20122073 DIETARY HYDROXYPROLINE INDUCES NEPHROLITHIASIS IN THE ADULT PORCINE MODEL Sutchin R. Patel, Kristina L. Penniston, Thomas D. Crenshaw, and Stephen Y. Nakada Sutchin R. PatelSutchin R. Patel Lake Bluff, IL More articles by this author , Kristina L. PennistonKristina L. Penniston Madison, WI More articles by this author , Thomas D. CrenshawThomas D. Crenshaw Madison, WI More articles by this author , and Stephen Y. NakadaStephen Y. Nakada Madison, WI More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.2239AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Our previous studies have shown that a 10% hydroxyproline and gelatin diet can both lead to long-term hyperoxaluria in the adult porcine model. However, no studies have shown nephrolithiasis formation in the adult porcine model. The purpose of our study was to evaluate both diets in the sow model for histologic crystal deposition and gross formation of nephrolithiasis. METHODS Two sows were fed a control diet and six sows were fed a diet of either 10% hydroxyproline or gelatin for 7, 14 and 21 days. Catheters were placed in the sows for 24 hour urine collection prior to the sows being sacrificed at either the 7 day, 14 day or 21 day timepoint. Both kidneys were removed and evaluated for gross stone formation. Renal tissue was fixed in formalin, stained with H&E and von Kossa and evaluated under light microscopy for calcium crystal deposition. Urine was analyzed via ion chromatography for oxalate. RESULTS Mean urinary oxalate concentration for sows on the control diet was 74 mg/L. Urinary oxalate concentrations for the 10% HP diet were 147, 352 and 89 mg/L at 7, 14 and 21 days. Urinary oxalate concentrations for the gelatin diet were 46, 4 and 132 mg/L at 7, 14 and 21 days. Histology revealed calcium crystal formation in the distal collecting ducts and renal papillae in one kidney of the 21 day, 10% hydroxyproline diet sow. Gross pathology revealed 7 renal calculi and calcification at the papillary tips in the same kidney of the 21 day, 10% hydroxyproline diet sow. Chemical analysis of the calculi revealed a composition of 20% calcium oxalate monohydrate, 78% calcium oxalate dihydrate and 2% protein. CONCLUSIONS A long-term 10% hydroxyproline diet leads to calcium oxalate nephrolithiasis in the adult porcine model. This is the first reported case of calcium stone formation in the adult porcine model and has important implications in the development of a dietary porcine model for urolithiasis. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e836 Peer Review Report Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sutchin R. Patel Lake Bluff, IL More articles by this author Kristina L. Penniston Madison, WI More articles by this author Thomas D. Crenshaw Madison, WI More articles by this author Stephen Y. Nakada Madison, WI More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Schismatoglottis and Apoballis (Araceae: Schismatoglottideae): A new example for the significance of pollen morphology in Araceae systematics

Pollen characters in Araceae accord well with recent DNA-based phylogenies, and here we provide a new example of "compass needle" quality in Araceae on the basis of two closely related genera, Schismatoglottis and Apoballis. All investigated Schismatoglottis pollen is psilate (smooth pollen surface) with calcium crystals covering the pollen surface. By contrast, pollen of species transferred to recently resurrected Apoballis (Apoballis acuminatissima and A. mutata) is distinctively echinate (spiny). A unique layer covers the endexine of Schismatoglottis, and the whole pollen surface of Apoballis. Our findings strongly suggest that "Schismatoglottis" species with echinate pollen fall into the genus Apoballis. Moreover, all schismatoglottid taxa perform spathe movements during anthesis to control the movement of pollinators. The spathe movements of Apoballis acuminatissima clearly differ from those known in Schismatoglottis species, and indeed are so far unique for the entire family. This, together with differences in floral odour is strongly suggestive of differences in pollination ecology between the genera Schismatoglottis and Apoballis.

Metabolism of crystals within the joint

Monosodium urate (MSU), calcium pyrophosphate dihydrate (CPPD) and basic calcium phosphate (BCP) crystals deposit in joints and surrounding tissues causing acute inflammation and chronic cartilage damage. A number of endogenous substances and physicochemical conditions affect their precipitation, growth and even dissolution, regulating their metabolism and inflammatory activity. We review how MSU and calcium crystals form within the joints and the various factor which regulate their formation.

Response to 'Plasma proteins present in osteoarthritic synovial fluid can stimulate cytokine production via Toll-like receptor 4'

We would like to add some comments with regard to our own experimental data concerning the immunomodulatory effect of plasma on calcium crystal-induced inflammation to findings outlined by Sohn and colleagues. Our results show that healthy human plasma in THP1 cells is able to enhance the release of IL-1beta and IL-8 in a dose dependent manner but the effect is higher when plasma is replaced by serum. We noted that fibrinogen is able to increase the inflammatory action of crystals with a more marked effect on IL-8. Showing a direct effect both on cells and on crystals, fibrinogen has an overall effect on the modulation of the inflammatory response to calcium crystals.

Osteoarthritis: a look at pathophysiology and approach to new treatments: a review

Objective: To review old, current, emerging and potential pathophysiological mechanisms in osteoarthritis and its approach to new treatments. Data sources: Published original research work and reviews from 1995 till early 2008 were searched in English on subjects related to pathogenesis, pathophysiology and potential new approaches to treatment of osteoarthritis. Study design: Articles that emphasized the pathogenesis and pathophysiology and new treatment approaches to the management of osteoarthritis. Data extraction: Online and manual library searches. Data synthesis: Data added up and summarized. Conclusion: Although osteoarthritis is characterized by cartilage degeneration, changes also involve the synovial membrane and the subchondral bone. Evidence suggests the involvement of a number of factors in the pathogenesis of osteoarthritis, like the proteases,pro-inflammatory cytokines, nitrous oxide, calcium crystals, leptin, angiogenesis and T cells and in turn using some of these to formulate some of the potential for new treatments for osteoarthritis.