SEARCH · PubMed Health

Results for “Calcium Pyrophosphate”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 667 records · Page 37Linked to original sources

PubMed2005

Evaluation of dentin abrasion during professional tooth cleaning in an in vitro model.

OBJECTIVES: Professional tooth cleaning (PTC) may lead to loss of exposed dentin. The aim of the present study was to determine the absolute loss of dentin during PTC using various product combinations with an in vitro model. MATERIAL AND METHODS: Dentin specimens (72) were randomly assigned to nine groups. In four groups each, prophy brushes and prophy cups were used in combination with four different abrasives (calcium pyrophosphate, pumice, Hawe cleanic, Nupro coarse). In the ninth group, a rubber cup with embedded fluoride and abrasives was used (pasteless prophy cup). The treatment time was 37 s. Surface loss was determined by profilometry. RESULTS: The surface loss in the nine groups was as following: (1) brush/calcium pyrophosphate: 6.18 microm (a); (2) brush/pumice: 5.51 microm; (3) brush/Nupro coarse: 10.10 microm (b); (4) brush/Hawe cleanic: 1.88 (a, b); (5) prophy cup/calcium pyrophosphate 2.07 (c); (6) prophy cup/pumice: 6.07 microm; (7) prophy cup/Nupro coarse: 5.93 microm (c); (8) prophy cup/Hawe cleanic: 4.93 microm (c); (9) pasteless prophy cup: 11.86 microm (c). Groups with the same letter in parentheses are statistically significant different at p<0.05. In a pooled analysis, no statistically significant difference between brushes and prophy cups was found. CONCLUSION: In the present study, the surface loss of about eight PTC procedures was simulated. Hence, the dentin loss ranged between 0.24 and 1.48 microm per PTC. Therefore, PTC does not seem to be a main factor in dentin loss.

Acidulated Phosphate Fluoride↗

PubMed1999

What is the relation between crystals and osteoarthritis?

The nature of the relation between osteoarthritis and the various forms of calcium crystals that are found within osteoarthritic joints continues to challenge and confound researchers. The most basic question is whether such crystals are directly relevant to the development of osteoarthritis, or are merely a byproduct or marker of the disease itself. The past year has produced several studies that elucidate important aspects of the molecular and cellular mechanisms of calcium pyrophosphate dihydrate and apatite crystal formation. Such studies may yield novel targets for therapeutic intervention in crystal-associated osteoarthritis. Other recent studies have provided further understanding of the mechanisms by which crystals induce inflammation. Arthroscopic assessment of patients with knee osteoarthritis refractory to traditional therapy suggests that the combined absence of chondrocalcinosis on plain films and identifiable crystals on compensated polarized light microscopy of synovial fluid from arthrocentesis may not be adequate to exclude clinically relevant crystalline deposition and inflammation. Clinical criteria are needed to identify patients with occult crystalline disease who, by virtue of crystal-induced inflammation, require more aggressive anti-inflammatory therapy than those with noninflammatory osteoarthritis.

Animals↗

PubMed2005

Hypomagnesemia and chondrocalcinosis in short bowel syndrome.

Chondrocalcinosis is a result of deposition of calcium pyrophosphate dihydrate (CPPD) crystals in cartilage and fibrocartilage. Chondrocalcinosis is usually sporadic but has also been associated with a variety of metabolic diseases including hypomagnesemia. Reported cases of hypomagnesemia associated chondrocalcinosis were mostly due to renal genetic disorders such as Bartter's or Gitelman's syndrome. We describe 3 patients with chronic hypomagnesemia induced by short bowel syndrome who developed symptomatic chondrocalcinosis. CPPD crystals were identified by polarizing light microscopy in one patient. The underlying intestinal pathology was radiation enteritis in 2 patients and mesenteric arterial thrombosis in the third. Our observations strengthen the hypothesis of a role for magnesium in CPPD crystal deposition disease.

Aged↗

PubMed1998

Hyponatremia in a patient with chronic inflammatory disease.

A 66-year-old man was admitted with destructive arthropathy, and calcium pyrophosphate dihydrate was demonstrated in the synovial fluid specimen. He was found to have a hyponatremia. The serum sodium concentration was 121 mmol/l, plasma arginine vasopressin (AVP) 6.6 pmol/l, and serum interleukin (IL)-6 96 pg/l. The clinical findings suggest the diagnosis of syndrome of inappropriate secretion of antidiuretic hormone (SIADH). However, destructive arthropathy with increased values of C-reactive protein and IL-6 is the only background of SIADH in this patient. We suggest the possibility that IL-6 produced at inflammatory lesions may have stimulated an excessive release of AVP resulting in the hyponatremia and hypochloremia of SIADH.

Aged↗

PubMed1990

Amyloid in intervertebral discs of surgery and autopsy material. A new class of amyloid?

Intervertebral discs from 82 consecutive operations on herniation and 59 autopsies (one case with generalized amyloidosis) were studied. Amyloid deposits observed in surgical and autopsy specimens increased with age in both series. Degenerative changes were related to age and to amyloid deposits in autopsy, but not in surgical cases. Calcium pyrophosphate dihydrate deposits (often in proximity to amyloid deposits) were found in autopsy discs of six patients and in surgical specimens of three patients with previous operations on herniated discs. Antisera against amyloid fibril proteins of different types including AA-, A lambda-, A kappa, AF- and AB-types showed no reaction with disc amyloid. In one case with generalized A lambda-amyloidosis the disc amyloid was not of the A lambda-type. Based on our results, we suppose that disc amyloid is a form of localized senile amyloidosis - possibly representing a new class of amyloid limited to cartilage tissue.

Adult↗

PubMed2005

Molecular dynamics simulation studies of the effect of phosphocitrate on crystal-induced membranolysis.

In this study, following our earlier work on calcium pyrophosphate dihydrate (CPPD) crystal-induced membranolysis, we demonstrate, using the CHARMM method of molecular dynamics simulation, the protective role of phosphocitrate (PC) against solvated dimyristoyl phosphatidylcholine phospholipid bilayer disintegration on contact with the CPPD crystal. Our molecular dynamics simulations studies show that coverage of the CPPD crystal with a layer of phosphocitrate molecules results in the conservation of phospholipid bilayer integrity. We show that the rupture of the lipid bilayer in presence of CPPD and the protective effect of PC are primarily due to electrostatic interactions. The protective role of PC, which may also play an important and potentially therapeutic function against crystal-induced membranolysis is also discussed.

Animals↗

PubMed1984

Rat and human polymorphonuclear leukocyte derived lymphocyte stimulatory factors.

The kinetic release of lymphocyte activating factors by inflammatory rat polymorphonuclear leukocytes (PMNs) into culture fluid was studied. PMNs, collected from the pleural cavity of rats 4 hours after injection of either calcium pyrophosphate (CaPP) or normal plasma, released into the supernatant culture fluid, factors which enhanced the phytohaemagglutinin-induced proliferative response of normal lymph node cells or thymocytes, the optimal culture time being 24 hours. A major portion of these lymphocyte activating factors was found in the ultrafiltrates (less than 10,000 daltons) of PMN supernatants. The activities in both unfractionated supernatant and the ultrafiltrate were significantly enhanced if PMNs were exposed to Concanavalin A (Con A) or inflammatory exudate prior to supernatant production. Also, these were not species specific as rat PMN supernatant can stimulate the phytohaemagglutinin-induced response of human lymphocytes and, conversely, human PMN factors can stimulate rat thymocytes.

Animals↗

PubMed1981

A three-year study of the effect of a sodium fluoride-silica abrasive dentifrice on dental caries.

The purpose of this study was to determine if a 0.243% sodium fluoride-silica abrasive dentifrice provides greater anticaries efficacy than a 0.4% stannous fluoride-calcium pyrophosphate abrasive dentifrice. A sample of 1,824 schoolchildren was randomly assigned to either the sodium fluoride dentifrice or the stannous fluoride dentifrice and examined clinically and radiographically for dental caries initially and after one, two, and three years of dentifrice usage. Two examiners independently examined each of the subjects for dental caries. After three years of ad libitum dentifrice usage, the results for both examiners showed that the group brushing with the sodium fluoride dentifrice had significantly lower DMF tooth and DMF surface increments than the group brushing with the stannous fluoride dentifrice. The percent reductions for DMF teeth were 14.8% and 10.5%, and for DMF surfaces 16.4% and 13.1% for the two examiners, respectively.

Adolescent↗

PubMed1991

Kinetics of IL1 beta mRNA and protein accumulation in human mononuclear cells.

Interleukin 1 beta (IL1 beta) is an inducible polypeptide with many roles in host defence and homoeostasis. It has also been implicated as a mediator of infectious, inflammatory and autoimmune diseases, and the kinetics of its production are relevant to an understanding of the pathogenesis of these conditions. We report here the time-course of IL1 beta production in human adherent monocytes. Both IL1 beta protein and mRNA were measured following cell activation with bacterial endotoxin (lipopolysaccharide; LPS), and pro-inflammatory crystals of monosodium urate (MSU), which cause arthritis and kidney disease. We also tested other crystal types associated with arthritis, namely hydroxylapatite and calcium pyrophosphate dihydrate. IL1 was absent from unstimulated cells, but IL1 beta mRNA accumulated rapidly after LPS or MSU stimulation and was associated with the later appearance of intracellular IL1 beta protein which was subsequently released from the cells (60% at 9 h). The other crystals failed to induce significant IL1 production. Our findings support the view that production of IL1 beta in human mononuclear cells is based on rapid translation of an inducible pool of mRNA and that no pre-formed mRNA or intracellular protein exists in normal blood monocytes. Further, although IL1 beta is translated without a conventional leader sequence, it is translocated extracellularly with the kinetics of a secretory protein.

Blood Proteins↗

PubMed1985

Sodium diethyldithiocarbamate influences the early immunological changes evoked by an acute non-antigenic inflammation process.

Calcium pyrophosphate (CaPp) produces an acute local inflammatory process when administered intra-pleurally. It is the simplest model of an inflammation uncomplicated by pharmacological properties of the agent or the presence of an antigen. Spleen or lymph-node T- or B-cell numbers and activities, including NK activity, are modified within 2 h under these conditions. A treatment with sodium diethyldithiocarbamate (lmuthiol), already known as a T-cell augmenting agent, restores towards normal values both the inflammatory reaction and the modified immune parameters induced in mice by CaPp pleurisy. The use of lmuthiol as a non-toxic, non-steroidal antiinflammatory agent is therefore suggested.

Animals↗

PubMed1999

Ankylosing spondylitis with severe chondrocalcinosis: case report.

The term chondrocalcinosis is often used to describe the radiological or pathological features of calcified joint cartilage, and it usually indicates the deposition in cartilage of calcium pyrophosphate dihydrate. The prevalence of chondrocalcinosis increases with age, with dramatic increases occurring in the decades past age 60. In younger patients with chondrocalcinosis, either clinical evidence of associated metabolic diseases leading to the chondrocalcinosis or familial disease occurrence usually can be detected. We report a 42-year-old Chinese woman with ankylosing spondylitis and arthritis involving multiple peripheral joints. Severe chondrocalcinosis was detected incidentally in this patient, however, subsequent studies revealed no associated metabolic disease or familial susceptibility and the clinical features of this patient were different from those of ankylosing chondrocalcinosis (pseudoankylosing spondylitis). The cause of chondrocalcinosis in this patient remains unknown, but joint damage and repair could have been initiating or aggravating factors of the chondrocalcinosis.

Adult↗

PubMed1987

Crystal-induced inflammation in the rat subcutaneous air-pouch.

Monosodium urate (MSU) and calcium pyrophosphate dihydrate (CPPD) crystals initiated acute inflammatory reactions characterized by increased plasma extravasation and polymorphonuclear leukocyte (PMNL) accumulation in the rat subcutaneous air-pouch. Pretreatment of rats with colchicine (1 mg kg-1, s.c.) inhibited PMNL accumulation induced by either crystal type but had a greater inhibitory effect on MSU-induced plasma extravasation compared with that induced by CPPD crystals. Colchicine (1 mg kg-1, s.c.) did not reduce histamine-induced plasma extravasation in the air-pouch. The lipoxygenase product of arachidonic acid metabolism, leukotriene B4 (LTB4), was detected in MSU-induced exudates but not in CPPD-induced exudates. Pretreatment of rats with colchicine (1 mg kg-1, s.c.) inhibited LTB4 production in MSU-induced exudates.

Animals↗

PubMed1984

Direct and indirect in vivo stimulation of LAF-like production induced by acute nonspecific inflammatory processes.

Peritoneal macrophages harvested from animals undergoing an acute non-immunological inflammatory reaction induced by an injection of calcium pyrophosphate ( CaPP ) or dextran into the pleural cavity showed an enhanced level of production of a lymphocyte activating factor (LAF) like material. On the other hand, macrophages harvested from the site of inflammation did not show enhanced production of this activity when compared to macrophages derived from normal controls. This enhanced activity was observed for up to two/three days after initiation of the inflammatory reaction and was obtained in both the presence and absence of lipopolysaccharide (LPS) during in vitro cultivation. Thus these results demonstrate that the acute inflammatory reaction, initiated by a non-antigenic stimulus ( CaPP ), is able to stimulate macrophages remote from the inflammatory site to produce a factor which behaves like LAF in a standard LAF assay.

Animals↗

PubMed1985

Pseudogout presenting with low synovial fluid glucose: identification of crystals by gram stain.

A man developed acute monoarticular ankle arthritis caused by calcium pyrophosphate dihydrate (CPPD) crystals. The clinical syndrome resembled that of a pyogenic arthritis. Synovial fluid analysis revealed a glucose concentration of 13 mg/dL and 99,000 white blood cells/mm3. Only one other report of an extremely low synovial fluid glucose associated with pseudogout could be found. The diagnosis of pseudogout was initially suggested when rhomboidal forms were seen during synovial fluid Gram stain examination. Synovial fluid examination with polarized microscopy was initially negative, but revealed numerous CPPD crystals when repeated on the third hospital day. This case serves to illustrate how pseudogout can mimic pyogenic arthritis in both clinical presentation and low synovial fluid glucose concentration. The examination of Gram-stained synovial fluid can reveal the rhomboidal forms of CPPD crystals. The appearance of these crystals is documented in this report.

Arthritis, Infectious↗

PubMed1985

Modifications of host defence mechanisms by an acute non-immunological inflammatory reaction.

Mice developing an acute non-immunological inflammatory reaction were examined for modification of specific and non-specific defence mechanisms on the basis of previous observations that these animals displayed an increased resistance to bacterial and parasitic infections but an impaired resistance to neoplasia. Local acute inflammation was induced by injection into the pleural cavity of a non-antigenic, endotoxin-free irritant--calcium pyrophosphate microcrystals or low-molecular-weight dextran. Effector functions of macrophages at remote sites from the inflammatory focus were markedly stimulated. This was shown by: (a) an accelerated elimination of Listeria monocytogenes in the liver and spleen of mice with inflammation; (b) the acquisition of cytostatic activity for tumour cells by peritoneal macrophages; and (c) an enhancement of chemiluminescence emission and superoxide production in response to phagocytosis. Natural killer activity of spleen and peritoneal cells was stimulated in a biphasic manner. In contrast, cytolytic T cell differentiation upon in vitro immunization of spleen cells against allogeneic tumour cells was impaired. All these effects were observed very early (2 h) after the onset of inflammation and were still detectable at least 3 days after the inflammatory process had disappeared.

Animals↗

PubMed1988

Substance-P-like levels in inflammatory exudates.

Levels of SP-like immunoreactivity were assessed by enzyme immunoassay in exudates induced in the rat by intrapleural injection of either calcium pyrophosphate (CaPP) or carrageenan. SP-like levels increased during the first hour, up to approximately 2 ng/ml, and remained significantly higher than control values from 1 to 6 h after the induction of pleurisy by CaPP. With carrageenan as the irritant, SP-like levels rose during the first 4 h, up to 3 ng/ml, and remained significantly higher than control values from 4 to 24 h. In terms of the total volume of exudate induced by carrageenan, total amounts increased up to 8 ng/rat at 16 h after the beginning of the reaction. Our data demonstrate a detectable release of SP-like material in these pleural exudates and suggest its involvement in the inflammatory response, either directly, or through other mediators, or simply by acting on nociceptive fibers and inducing vascular changes.

Animals↗

PubMed1983

An ultrastructural study of articular chondrocalcinosis in cases of knee osteoarthritis.

A study was made by transmission electron microscopy of tissue specimens (cartilage, meniscus and synovial membrane) taken from 5 knees presenting radiological and anatomical signs of articular chondrocalcinosis and osteoarthritis. It was part of a broader study which included analysis of the same specimens by macroscopy and light microscopy as well as by X-ray diffraction of the mineral deposits. In cartilage and meniscus juxta-cellular calcium pyrophosphate dihydrate (CPPD) crystals of variable sizes were observed in the extracellular organic matrix, independent of the collagen fibrils. They occurred mainly in the superficial and middle zones but could also be seen intermingled with the apatite crystals in the cartilage calcified zone. In synovial membrane most of the CPPD crystals were extracellular but some of them could be seen in cytoplasmic phagocytic vacuoles. These observations are in agreement with those in the literature regarding the ultrastructural picture of chondrocalcinosis and support the thesis that the crystals originate in the cartilage and are phagocytized in the synovial membrane. Although the results of the present study do not provide direct evidence of a relationship between chondrocalcinosis and osteoarthritis, the data of the ultrastructural investigation appear nevertheless of great interest as a complement to the data furnished by light microscopy.

Adult↗

PubMed1989

Inflammatory microcrystals stimulate interleukin-6 production and secretion by human monocytes and synoviocytes.

Crystal-related joint diseases are often associated with systemic inflammatory manifestations, including increased levels of acute-phase proteins, leukocytosis, and fever. Recently, interleukin-6 (IL-6) has been identified as a pluripotent mediator of inflammatory and immunologic responses and the major hepatocyte-stimulating factor. In this study, we demonstrated that monosodium urate (MSU) and calcium pyrophosphate dihydrate (CPPD) crystals, and to a lesser extent, hydroxyapatite crystals, increased IL-6 production by synoviocytes and monocytes in vitro. Immunoprecipitation experiments showed that MSU and CPPD crystals, but not hydroxyapatite crystals, were able to increase the release of newly synthesized IL-6. Crystal-induced IL-6 stimulated acute-phase protein synthesis, immunoglobulin production, and hybridoma cell proliferation, which was neutralized by a specific antibody to IL-6. High levels of IL-6 were found in synovial fluid from patients with gout and pseudogout. These results demonstrate that MSU and CPPD crystals can induce IL-6 production in synoviocytes and monocytes, and that synovial fluid from patients with gout and pseudogout contains high levels of IL-6. Crystal-induced IL-6 is likely to be an important mediator of inflammatory responses in acute gout and pseudogout.

Calcium Pyrophosphate↗