Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PYROPHOSPHATES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 1,135 records · Page 63Linked to original sources
PubMed1987

Prognostic value and limitation of doughnut pattern of technetium-99m pyrophosphate myocardial uptake in acute anterior infarction.

The prognostic significance of the doughnut pattern of technetium-99m pyrophosphate myocardial uptake was evaluated in 140 patients with acute anterior infarction. There were significantly higher early complications, greater mortality and more severe hemodynamic abnormalities in the doughnut pattern group than in the non-doughnut pattern group. The former had a more depressed left ventricular ejection fraction and larger thallium-201 defect size (27.6 +/- 10.4 versus 40.0 +/- 13.5%, p less than 0.001 and 9.9 +/- 3.6 versus 5.6 +/- 3.3, p less than 0.001, respectively). There was, however, considerable overlap of the ranges of these variables for both groups. The patency rate of the infarct vessel during the acute phase of infarct in each group was similar (54.8 versus 45.2%). It is concluded that the prognostic value of the doughnut pattern may be limited to some extent by this overlapping and the presence of this pattern does not appear to correlate with the lack of residual blood flow to the infarcted area.

Cardiac Catheterization↗
PubMed1992

Effect of diltiazem on stunned myocardium evaluated with 99mTc-pyrophosphate imaging in canine heart.

The effect of diltiazem on stunned myocardium was evaluated by measuring the myocardial uptake of 99mTc-PYP (pyrophosphate) in open chest experiments with dogs. Myocardial stunning was induced by a 30 min ischemic occlusion of the anterior descending coronary artery. Regional wall motion was monitored by echocardiography of the epicardium for 2 h during reperfusion. After a 30 min occlusion of the coronary artery, it was reperfused and 99mTc-PYP was injected, followed by 201Tl 2 h later. The ischemic area was defined by Evans blue dye, and the infarct area by TTC staining. No dogs showed infarcts or 201Tl defects in this study group. Five dogs of the control-1 group (C1, ischemic area = 19.1 +/- 3.2%) showed decreased regional wall motion during occlusion (15.5 +/- 3.5% of control), and a slow recovery from depressed motion after 2 h of reperfusion (20.3 +/- 9.3%) with uptake ratio (compared to the non-ischemic area uptake) of 99mTc-PYP (4.96 +/- 2.28). In contrast, both groups with diltiazem infusion (20 micrograms/kg/min), started either 30 min before ischemia (D1 = 5 dogs) or just after reperfusion (D2 = 5 dogs), showed significantly better recovery after 2 h of reperfusion (D1:115.4 +/- 36.0%, D2:109.2 +/- 44.2%) than C1 (p less than 0.05), D1 and D2 groups also showed suppressed 99mTc-PYP uptake ratio (D1:1.06 +/- 0.33, D2:2.34 +/- 2.05, p less than 0.05 vs C1) in spite of comparable ischemic area. Four dogs with small ischemic area (C2:5.3 +/- 5.0%) did not show increased 99mTc-PYP uptake (1.15 +/- 0.35), and regional wall motion after 2 h of reperfusion was 96.1 +/- 24.1% of the control value (p less than 0.05 vs C1). Thus, diltiazem was effective in enhancing the suppression of 99mTc-PYP uptake in the stunned myocardium, and similar results were obtained for small ischemic areas. The protective effect of diltiazem appears to be strongly related to the mechanism of 99mTc-PYP uptake.

Animals↗
PubMed1999

New method of estimating myocardial infarct size using technetium-99m pyrophosphate and thallium-201 dual single photon emission computed tomography imaging.

A new method was devised to estimate infarct size using dual single photon emission computed tomography with thallium-201 and technetium-99m pyrophosphate. Designating the ratio of infarct area to whole myocardial volume as %MI, the correlation of %MI with other markers of left ventricular dysfunction was examined: peak creatine kinase, ejection fraction and left ventricular asynergy. As %MI correlated well with these markers, it is considered that %MI will be useful for estimating infarct size and predicting the severity of left ventricular dysfunction in the early stage of acute myocardial infarction.

Adult↗
PubMed1999

Deposition of calcium pyrophosphate in tissue after revision arthroplasty of the hip.

We reviewed histologically the incidence and pathogenesis of the deposition of calcium pyrophosphate dihydrate (CPPD) crystals in the pseudocapsule, femoral and acetabular membranes and periprosthetic tissue at revision of 789 cases of failed total hip replacement. In 13, periprosthetic tissues were found to have deposits of CPPD crystals in areas of cartilaginous metaplasia; four also showed evidence of localised deposition of amyloid. None of the patients had a history of chondrocalcinosis in the hip or other joints. Cartilaginous metaplasia and other changes in periprosthetic tissues may predispose to the deposition of CPPD and associated localised amyloid.

Acetabulum↗
PubMed2004

Thiamine pyrophosphate biosynthesis and transport in the nematode Caenorhabditis elegans.

Thiamine (vitamin B1) is required in the diet of animals, and thiamine deficiency leads to diseases such as beri-beri and the Wernicke-Korsakoff syndrome. Dietary thiamine (vitamin B1) consists mainly of thiamine pyrophosphate (TPP), which is transformed into thiamine by gastrointestinal phosphatases before absorption. It is believed that TPP itself cannot be transported across plasma membranes in significant amounts. We have identified a partial loss-of-function mutation in the Caenorhabditis elegans gene (tpk-1) that encodes thiamine pyrophosphokinase, which forms TPP from thiamine at the expense of ATP inside cells. The mutation slows physiological rhythms and the phenotype it produces can be rescued by TPP but not thiamine supplementation. tpk-1 functions cell nonautonomously, as the expression of wild-type tpk-1 in one tissue can rescue the function of other tissues that express only mutant tpk-1. These observations indicate that, in contrast to expectation from previous evidence, TPP can be transported across cell membranes. We also find that thiamine supplementation partially rescues the phenotype of partial loss-of-function mutants of the Na/K ATPase, providing genetic evidence that thiamine absorption, and/or redistribution from the absorbing cells, requires the full activity of this enzyme.

Adenosine Triphosphate↗
PubMed2000

Retro-odontoid massive calcium pyrophosphate crystal deposition--case report.

An 86-year-old male presented with progressive myelopathy due to retro-odontoid massive deposits of calcium pyrophosphate dihydrate (CPPD) crystals. Magnetic resonance imaging revealed a non-enhanced isointense extradural mass on the T1-weighted image and heterogeneously intense mass on the T2-weighted image. Computed tomography showed typical punctate and linear calcifications within the mass. The mass was resected via a lateral approach resulting in marked improvement of the symptoms. Histological examination revealed birefringent rhomboid crystals consistent with CPPD. CPPD deposition should be considered in the differential diagnosis of retro-odontoid extradural mass because surgical therapy is beneficial even for elderly patients.

Aged↗
PubMed1987

Sequential study of pleural peritoneal and blood cells in acute pleurisy induced by calcium pyrophosphate in the rat.

We studied the sequential cellular events that occur during nonspecific pleurisy induced by a nondiffusible, nonantigenic and endotoxin-free irritant, calcium pyrophosphate (CaPP). The study was conducted over 10 days and concerned not only the pleural cavity but also the peritoneal cavity and the blood. After injection of CaPP, the first cellular event in the pleural space was a "leukocyte disappearance reaction," followed by an important increase in the polymorphonuclear leukocytes (PMN) and then by an increase in the macrophages. This phase is also characterized by the appearance of submesothelial nodules composed of macrophages and numerous polymorphonuclear cells. All the cell populations returned to their normal value on day 10, although granulomatous submesothelial nodules were present. In the blood, the principal observation was an increased PMN count associated with a decreased lymphocyte count at 4 h. In the peritoneal cavity, it was remarkable that, although functional modifications have been reported in the same model, the different leukocyte populations did not vary during the reaction.

Animals↗
PubMed2001

Induction of matrix metalloproteinase-8 in human fibroblasts by basic calcium phosphate and calcium pyrophosphate dihydrate crystals: effect of phosphocitrate.

Although matrix metalloproteinase-8 (MMP-8) was regarded as the exclusive product of the neutrophils, recent studies have shown that it is also expressed in articular chondrocytes, rheumatoid synovial fibroblasts and endothelial cells. Our aim was to determine the expression of MMP-8 in human fibroblasts (HF) by reverse transcription/polymerase chain reaction (RT/PCR). Northern and Western blotting methods and MMP-8 activity assay. We have shown the expression of MMP-8 in HF and its dose-dependent upregulation by basic calcium phosphate (BCP) and calcium pyrophosphate dihydrate (CPPD) crystals which are markers of severe joint degeneration in osteoarthritis. These effects require new protein synthesis and are reversed by phosphocitrate (PC). The results also show that this fibroblast MMP-8 is distinct from the neutrophil MMP-8 and from the fibroblast MMP-1. These results indicate that MMP-8 may play a significant role in the pathogenic effects of the crystals in osteoarthritis.

Anti-Bacterial Agents↗
PubMed1980

Cervical radiculomyelopathy caused by deposition of calcium pyrophosphate dihydrate crystals in the ligamenta flava. Case report.

A case of cervical radiculomyelopathy caused by multiple calcified nodules in the ligamenta flava is presented. Roentgenological examination of the cervical spine showed radiopaque nodular lesions, 7 x 7 x 5 mm in size, located in the paramedian portion of the posterior spinal canal. The nodules were removed surgically and they were confirmed to be calcifications of ligamenta flava. Microscopic examination of the nodules with the polarized light revealed extensive deposition of crystals. By x-ray diffraction study, the crystal was determined as calcium pyrophosphate dihydrate (CPPD: Ca2P2O7 . 2H2O). Although CPPD deposition in the cartilage has been known as pseudo-gout syndrome, deposition in the ligament has been reported only in a few cases. This is the first case with radiopaque calcified nodules in the ligamenta flava causing spinal cord compression, the composition of which proved to be CPPD.

Calcium Pyrophosphate↗
PubMed1984

Calcium pyrophosphate dihydrate deposits in the cervical ligamenta flava causing myeloradiculopathy.

Three cases of cervical myeloradiculopathy associated with multiple calcified nodules containing identified calcium pyrophosphate dihydrate (CPPD) crystals in the ligamenta flava are described, with a comprehensive review of the 12 cases of this entity reported to date. The disease is characterized by: 1) oval or triangular areas of radiodensity in the posterior aspect of the cervical canal as seen in the lateral x-ray films and laminograms; 2) hemispherical areas of high density located almost symmetrically in the paramedial portion of the posterior spinal canal on computerized tomography scans; and 3) CPPD crystals in the nodules. It occurs independently or in association with cervical spondylosis or ossification of the posterior longitudinal ligament.

Aged↗
PubMed1992

Thiamin pyrophosphate binding mechanism and the function of the aminopyrimidine part.

Besides the pyrophosphate group, acting as the essential and primary binding function of TPP the N1-atom of the aminopyrimidine component functions as a second and also essential anchor to the protein component. Only if both of the contacts are formed the productive conformation of TPP within the active site of TPP enzymes is realized. A mechanism is proposed, which explains the results of our experiments with TPP-analogs.

Amines↗
PubMed1983

Phagocytosis of hydroxyapatite or calcium pyrophosphate dihydrate crystals by rabbit articular chondrocytes stimulates release of collagenase, neutral protease, and prostaglandins E2 and F2 alpha.

Synthetic hydroxyapatite (HA) and calcium pyrophosphate dihydrate (CPPD) microcrystals are phagocytosed by rabbit articular-cartilage chondrocytes in primary culture. The ingestion of crystals greatly stimulated the release of collagenase, neutral protease, and prostaglandins E2 and F2 alpha into the ambient medium. Lactate dehydrogenase was not released by either crystal despite electron microscopic evidence of cell damage by HA crystals (partial loss of phagolysosomal membrane and increased myelin figures). HA, but not CPPD crystals, stimulated release of beta-glucuronidase. HA crystal concentrations from 50 to 200 micrograms ml-1 induced a dose-dependent release of collagenase and of extracellular protein. Both phagocytosis and collagenase release were greatly attenuated when HA crystals were added to the chondrocyte monolayers in the absence of serum. As HA and CPPD crystals have been identified in human articular cartilage in association with degenerative changes, it is possible that the cell-crystal interaction described here may be pathogenetically important.

Animals↗
PubMed2003

Idiopathic calcium pyrophosphate dihydrate (CPPD) crystal deposition disease in a young male patient: a case report.

Calcium pyrophosphate dihydrate (CPPD) crystal deposition disease is a disease of the elderly and extremely rare in young individuals. If young people develop CPPD crystal deposition disease, it may be associated with metabolic diseases such as hemochromatosis, hyperparathyroidism, hypophosphatasia, hypomagnesemia, Wilson's disease, hypothyroidism, gout, acromegaly, and X-linked hypophosphatemic rickets. Therefore, in young-onset polyarticular CPPD crystal deposition disease, investigation for predisposing metabolic conditions is warranted. We report a case of a young male patient with idiopathic CPPD crystal deposition disease, who did not have any evidences of metabolic diseases after thorough evaluations. As far as we know, this is the first report of a young male patient presented with idiopathic CPPD crystal deposition disease.

Adult↗
PubMed1990

Calcium pyrophosphate dihydrate crystal deposition patterns in the triangular fibrocartilage complex.

To define the patterns of calcium pyrophosphate dihydrate (CPPD) crystal deposition in the triangular fibrocartilage complex (TFCC), we examined the wrists of five adult, fresh-frozen cadavers using light and scanning electron microscopy and the wrist radiographs of 10 patients with a clinical diagnosis of CPPD disease. The radiographs consistently showed mineral deposits near or on the proximal and distal surfaces of the radial half of the TFCC. Light and electron microscopy showed that CPPD crystals formed distinct clusters sharply demarcated from uninvolved fibrocartilage. The density of crystal packing within clusters varied with the sharpness of demarcation of the clusters from the surrounding tissue. TFCC defects were consistently found in the vicinity of CPPD crystals, and degeneration of the articular cartilage on the ulnar half of the proximal surface of the lunate was associated with CPPD crystal deposition in the radial half of the TFCC. These observations suggest that degenerative tears of the TFCC and degeneration of the articular cartilage of the lunate are associated with CPPD crystal deposits in the TFCC.

Adult↗
PubMed2000

Inhibition of TNF-alpha-induced neutrophil apoptosis by crystals of calcium pyrophosphate dihydrate is mediated by the extracellular signal-regulated kinase and phosphatidylinositol 3-kinase/Akt pathways up-stream of caspase 3.

The role of protein kinases in the inhibition of TNF-alpha associated apoptosis of human neutrophils by crystals of calcium pyrophosphate dihydrate (CPPD) (25 mg/ml) was investigated. We monitored the activities of the p44 extracellular signal-regulated kinase 1 (ERK1) and p42 ERK2 mitogen-activated protein (MAP) kinases and phosphatidylinositol 3-kinase (PI3-K)-regulated protein kinase B (Akt) in neutrophils incubated with TNF-alpha and CPPD crystals, separately and in combination, in parallel with the endogenous caspase 3 activity and DNA fragmentation. CPPD crystals were observed to induce a robust and transient activation of ERK1, ERK2, and Akt, whereas TNF-alpha produced only a modest and delayed activation of Akt. In the presence of TNF-alpha, Akt activity was enhanced, and CPPD crystal-induced activation of ERK1 and ERK2 was more sustained than with CPPD crystals alone, but TNF-alpha itself reduced the basal phosphotransferase activities of these MAP kinases. Preincubation with the MAP kinase kinase (MEK1) inhibitors PD98059 (20 ng/ml) and U0126 (250 nM), or the PI3-K inhibitors wortmannin (100 nM) and LY294002 (50 microM) repressed the activation of ERK1, ERK2, and Akt in association with CPPD crystal incubation, in the absence or presence of TNF-alpha. Furthermore, the inhibition of the Mek1/Mek2-->ERK1/ERK2 or PI3-K/Akt pathways reversed CPPD crystal-associated suppression of TNF-alpha-induced caspase 3 activation and neutrophil apoptosis. Together, these results indicate that CPPD crystals function to induce acute inflammatory responses through ERK1/ERK2 and PI3-K/Akt-mediated stimulation of neutrophil activation and repression of apoptosis.

Apoptosis↗
PubMed2005

TLR2 signaling in chondrocytes drives calcium pyrophosphate dihydrate and monosodium urate crystal-induced nitric oxide generation.

Microcrystals of calcium pyrophosphate dihydrate (CPPD) and monosodium urate (MSU) deposited in synovium and articular cartilage initiate joint inflammation and cartilage degradation in large part by binding and directly activating resident cells. TLRs trigger innate host defense responses to infectious pathogens, and the expression of certain TLRs by synovial fibroblasts has revealed the potential for innate immune responses to be triggered by mesenchymally derived resident cells in the joint. In this study we tested the hypothesis that chondrocytes also express TLRs and that one or more TLRs centrally mediate chondrocyte responsiveness to CPPD and MSU crystals in vitro. We detected TLR2 expression in normal articular chondrocytes and up-regulation of TLR2 in osteoarthritic cartilage chondrocytes in situ. We demonstrated that transient transfection of TLR2 signaling-negative regulator Toll-interacting protein or treatment with TLR2-blocking Ab suppressed CPPD and MSU crystal-induced chondrocyte release of NO, an inflammatory mediator that promotes cartilage degeneration. Conversely, gain-of-function of TLR2 in normal chondrocytes via transfection was associated with increased CPPD and MSU crystal-induced NO release. Canonical TLR signaling by parallel pathways involving MyD88, IL-1R-associated kinase 1, TNF receptor-associated factor 6, and IkappaB kinase and Rac1, PI3K, and Akt critically mediated NO release in chondrocytes stimulated by both CPPD and MSU crystals. We conclude that CPPD and MSU crystals critically use TLR2-mediated signaling in chondrocytes to trigger NO generation. Our results indicate the potential for innate immunity at the level of the articular chondrocyte to directly contribute to inflammatory and degenerative tissue reactions associated with both gout and pseudogout.

Adaptor Proteins, Signal Transducing↗
PubMed2000

Familial osteoarthritis and Milwaukee shoulder associated with calcium pyrophosphate and apatite crystal deposition.

OBJECTIVE: To characterize and define the phenotypes observed in a large Italo-Argentinean kindred with osteoarthritis, chondrocalcinosis, and Milwaukee shoulder (MS). METHODS: Seventy-five members were evaluated with a history, examination, and radiographs of shoulders, spine, hands, and knees. Superior subluxation of the glenohumeral joint was graded using shoulder radiographs and tomography and nuclear magnetic resonance imaging and 3 dimensional computed tomography was performed on selected members. In 31 family members peripheral blood DNA was utilized for genetic linkage analysis of several candidate gene loci previously linked to chondrocalcinosis phenotypes, as well as those implicated in the proper patterning of skeletal elements and cartilage differentiation. In addition, direct sequence analysis of type II collagen gene (COL2A1), the gene that codes for the major structural protein of cartilage, was undertaken in 3 affected and 3 unaffected members of the family. RESULTS: MS was seen in one member of the first generation and 6 members of the 2nd generation, while 8 members of the 3rd generation showed an incomplete form of MS. Isolated superior subluxation of the shoulder was seen in 16 other family members of the 3rd and 4th generations. Osteoarthritis of the spine and peripheral joints was seen in 31 affected members, while chondrocalcinosis was observed in 6 members of the first generation. Shoulder synovial fluid from 2 patients showed the presence of both apatite and calcium pyrophosphate dihydrate crystals. Direct analysis of the COL2A1 gene indicated no known disease determining mutations in affected members, thus excluding this gene as a candidate gene in this family. Genetic linkage to several candidate loci, including the chondrocalcinosis loci on chromosomes 5p and 8q, as well as loci for HOX A and C were also excluded. Linkage analyses of other loci for the HOX B and D genes and the PAX 1 and 9 genes were uninformative in this kindred. CONCLUSION: This kindred illustrates an unusual type of osteoarthritis with secondary intraarticular and periarticular calcification and MS in the most severely affected elderly members. A search for linkage to some potential candidate genes was either excluded or uninformative. Further linkage analysis to identify potential candidate genes is in progress.

Adult↗
PubMed2000

[Fever of unknown origin as a sign of calcium pyrophosphate deposition disease].

Calcium pyrophosphate dihydrate (CPPD) crystal deposition disease may manifest clinically as septic fever (40 degrees C), acute pseudogout attack of knee, wrist and shoulders, or as a variety of patterns of chronic inflammatory or degenerative joint disease. The association of pseudogout with fever is less widely recognised and may lead to over-investigation, delay in appropriate treatment and disproportionate costs. We report on a 67-year-old woman with a history of recurrent episodes of fever and polyarthritis every 2 months for the last 3 years. Because of this she was hospitalised several times, finally with suspected culture-negative endocarditis, and was treated for 6 weeks with gentamicin, rifampicin and vancomycin. During this therapy the patient again developed septic fever and acute arthritis of the right wrist. Radiographs of the wrist, knee and symphysis pubis revealed prominent chondrocalcinosis and destructive arthropathy.

Aged↗