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PubMed1983

Right ventricular myocardial infarction diagnosed by 99 m technetium pyrophosphate scintigraphy: clinical course and follow-up.

Out of 178 consecutive patients with acute inferior wall myocardial infarction submitted to technetium-99 m pyrophosphate scintigraphy, 49 (27.5%) were found to have concomitant right ventricular infarction. Gated blood pool scans showed right ventricular abnormalities in 21 out of 26 patients who were submitted to this investigation (right ventricular asynergy: 16 cases; right ventricular dilatation: eight cases; decreased right ventricular ejection fraction: 16 cases). Complications were common in the acute stage. Shock was noted in 19 cases (eight related to bradycardia, three related to relative hypovolaemia and eight instances of true cardiogenic shock). Atrial fibrillation (seven patients), ventricular fibrillation (eight patients) and severe atrioventricular conduction disorders (13 patients) were also frequent. In spite of this, the in-hospital mortality was low: three deaths occurred (6.1%), one from heart failure, two others from posterior septal rupture. All patients were followed up for one year or more. Six additional deaths were noted (three from left cardiac failure, two from recurrent anterior wall infarction and one from massive pulmonary embolism). Clinical assessment, haemodynamic measurements and gated blood pool scans showed significant improvement of right ventricular function with return to normal in those cases with small right ventricular infarcts as judged from technetium-99 m pyrophosphate scintigraphy. In spite of the complications seen in the initial period, patients with a right ventricular infarction have a good overall prognosis and the long-term outcome, primarily determined by the left-sided lesions, is often favourable.

Adult↗
PubMed1990

Synovial fluid calcium pyrophosphate dihydrate crystals and alizarin red positivity: analysis of 3000 samples.

Three thousand synovial fluids (1312 patients: chronic pyrophosphate arthropathy (CPA), 41%; osteoarthritis (OA), 12%; rheumatoid arthritis (RA), 16%) were examined for crystals, including calcium pyrophosphate dihydrate (CPPD), by polarized microscopy (score 0-3); calcific particles, by alizarin red positivity (ARP; 0-3); and total cell count. For 1150 fluids, local joint inflammation was assessed as 'active' or 'inactive' using a summated score of six clinical variables. CPPD and ARP scores did not correlate, but each showed positive correlation with age (P less than 0.01, P less than 0.02 respectively). Pseudogout had the highest mean CPPD score (P less than 0.001); intermittent CPPD positivity (range 8-100%) was seen in serially aspirated CPA joints, and there was no difference in CPPD positivity or score between active and inactive CPA. ARP was most frequent in OA subsets (72% of CPA, 46% of OA, 31% of RA; P less than 0.001). ARP was more frequent in active than inactive OA (P less than 0.05) but showed no association with inflammation in CPA or RA. Cell counts were higher in RA and pseudogout compared to OA and CPA, and in active compared to inactive RA. No correlation was found between ARP or CPPD scores and cell count. Cholesterol crystals were uncommon (0.2%) and showed no disease or joint predilection. In arthritic joints, CPPD and calcific particles particularly associate with the OA process and ageing. CPPD may contribute to acute and other calcific particles to chronic inflammation in OA.

Adolescent↗
PubMed1992

Tophaceous pyrophosphate deposition with extensor tendon rupture.

Tophaceous deposition of calcium pyrophosphate dihydrate (CPPD) crystals is considered unusual as is deposition within tendon sheaths. Associated tendon rupture is described but is rare. We report a lady with tophaceous CPPD deposition at the wrist, a previously unreported site. Contrary to previous cases, this occurred in the setting of symptomatic, polyarticular, pyrophosphate arthropathy. An additional point of interest was development of associated extensor tendon rupture with features favouring a non-inflammatory mechanism of tendon damage.

Aged↗
PubMed1993

Pyrophosphate arthropathy: a prospective study.

One hundred and four consecutive patients with pyrophosphate arthropathy were followed prospectively and re-studied at a mean of 4.6 years. Sixty-four patients (43F, 21M; mean age at review 71.2 years) completed the study (24 died of unrelated disease, 16 were unavailable for review). The knee had been the major presenting joint in 91%. Symptoms were improved in 41%, unchanged in 33% and had worsened in only 27%: 27% developed symptoms in new joints. Radiographic changes of arthropathy were unaltered in 50%: although 'worsening' of previously involved joints was seen in 16%, the most common change was increase in osteophyte with bone remodelling (31%). Despite dynamic changes in chondrocalcinosis in most patients (77%) there was no correlation between extent of calcification and progression of arthropathy. It is concluded that the outcome of pyrophosphate arthropathy is not necessarily progressive, patients presenting with acute attacks alone do particularly well.

Adult↗
PubMed1992

Effect of stannous pyrophosphate red blood cell gastrointestinal bleeding scan on subsequent Meckel's scan.

Both labeled RBC and Meckel's scans have been used to evaluate pediatric patients with gastrointestinal bleeding, sometimes sequentially in the same patient. Particularly in infants, from whom withdrawal of sufficient blood for in vitro RBC labeling is often not possible, in vivo labeling with stannous pyrophosphate is used. However, prior administration of stannous-containing agents is known to alter the in vivo distribution of Tc-99m pertechnetate and to interfere with the subsequent Meckel's scan. The authors report on a Meckel's scan performed on an infant 1 week after a GI bleeding study with Tc-99m and stannous pyrophosphate. The Meckel's scan shows abnormal tracer distribution with absent gastric uptake, rendering the scan uninterpretable. In pediatric patients with gastrointestinal bleeding, a Meckel's scan should be done before labeled RBC imaging.

Erythrocytes↗
PubMed2000

The importance of the five phosphoribosyl-pyrophosphate synthetase (Prs) gene products of Saccharomyces cerevisiae in the maintenance of cell integrity and the subcellular localization of Prs1p.

Phosphoribosyl-pyrophosphate synthetase (Prs) catalyses the synthesis of phosphoribosyl pyrophosphate (PRPP), an intermediate in nucleotide metabolism and the biosynthesis of the amino acids histidine and tryptophan. The Saccharomyces cerevisiae genome contains a family of five PRS genes, PRS1-PRS5. Using anti-peptide antisera directed against two different epitopes of Prs1p it was shown that Prs1p localizes to granular cytoplasmic structures. This localization was confirmed by living cell microscopy of strains expressing a functional green fluorescent protein (GFP)-tagged Prs1p. Analysis of Prs1p distribution in conditional secretory-deficient (sec) mutants suggested that the observed distribution of Prs1p is independent of the secretory pathway. Electron microscopy revealed that plasma membrane invaginations and accumulation of cytoplasmic vesicles were more frequent in strains which lack some of the PRS genes than in the wild-type. The fact that Deltaprs1 and Deltaprs3 are hypersensitive to caffeine and unable to recover from exposure to it as judged by the release of alkaline phosphatase points to a possible link between Prs and the maintenance of cell integrity.

Alkaline Phosphatase↗
PubMed2000

Structure of the beta form of calcium pyrophosphate tetrahydrate.

beta-Ca(2)P(2)O(7).4H(2)O is monoclinic, P2(1)/c, a = 12.287 (6), b = 7.511 (3), c = 10.775 (5) A, and beta = 112.54 (1) degrees. Five of the terminal O atoms from a pyrophosphate group bind to Ca atoms, together with O atoms from three of the water molecules. The fourth H(2)O forms only hydrogen bonds. Both Ca atoms have coordination number 7 and show characteristics between those of a capped octahedron and a pentagonal bipyramid. The analysis of coordination distortions suggests that regularity and volume efficiency of a Ca coordination polyhedron increases with the number of bound water O atoms. The structure is layered after ¿100¿, reflected also in the morphology of crystals which are formed as extremely thin plates. The central parts of the layers are formed by chains of Ca coordination polyhedra which run along the b axis and are interconnected by pyrophosphate groups. Water molecules form the surfaces of the layers. A peculiar auto-inhibition of growth from supersaturated solutions is supposed to be caused by a direct attachment of CaP(2)O(7)(2-) and P(2)O(7)(4-) to the water molecules on the surfaces of layers. Ca(2)P(2)O(7).4H(2)O is known in two polymorphs. The unit-cell volume of the beta form compared with that of alpha suggests that the former is a low-temperature modification.

Calcium Pyrophosphate↗
PubMed1993

Thiamine pyrophosphate effect and erythrocyte transketolase activity during severe alcohol withdrawal syndrome.

The thiamine pyrophosphate (TPP) effect and erythrocyte transketolase activity (ETKA) in a group of 28 patients admitted to a psychiatric emergency ward because of severe alcohol withdrawal syndrome were compared with the TPP effect and ETKA in a control group of 20 healthy nonalcoholic volunteers. The patients were treated with 300 mg thiamine 3 times daily as intramuscular injections, and the TPP effect and ETKA were measured after 1 and 4 days of treatment. No difference was found between the patient group and the control group with regard to the TPP effect and ETKA and no decline in the TPP effect was found in the patient group after 4 days of intensive treatment with thiamine. ETKA increased with intensive thiamine treatment, which suggests that ETKA is a sensitive indicator of thiamine deficiency. Serum magnesium, which is a cofactor for thiamine pyrophosphate, decreased significantly with the disappearance of alcohol from the blood in patients with high initial blood alcohol levels, but this shift did not interfere with biological thiamine activity.

Adult↗
PubMed1996

Thiamine pyrophosphate (TPP) negatively regulates transcription of some thi genes of Salmonella typhimurium.

In Salmonella typhimurium, thiamine is a required nutrient that is synthesized de novo. Labeling studies have demonstrated probable precursors for both the 4-amino-5-hydroxymethyl-2-methylpyrimidine pyrophosphate moiety and the 4-methyl-5-(beta-hydroxyethyl) thiazole monophosphate moiety. The isolation of thiamine auxotrophs with mutations in at least five different genetic loci is reported. The majority (22 of 25) of the mutants required only the thiazole moiety of thiamine to satisfy their growth requirement. Most (14 of 25) of the mutants were affected in the thi cluster at min 90 on the S. typhimurium genetic map. Data provided herein indicate that this cluster encodes an operon whose transcription is regulated by thiamine and suggest that thiamine pyrophosphate, or a molecule derived form it, is the effector molecule. Mutants with altered regulation of this operon were isolated, and we propose that they are defective in thiamine phosphate kinase, the product of the thiL gene.

Amino Acid Sequence↗
PubMed1977

Carpal instability in rheumatoid arthritis and calcium pyrophosphate deposition disease. Pathogenesis and roentgen appearance.

The roentgen appearance and pathogenesis of carpal instability are described in an evaluation of patients and cadavers with rheumatoid arthritis and calcium pyrophosphate deposition disease. Dorsiflexion (16%) and palmar flexion (8%) instability occurs in rheumatoid arthritis, particularly in patients with moderate to advanced disease. Navicular-lunate dissociation frequently accompanies dorsiflexion instability and results from involvement of the interosseous ligament between the two bones by rheumatoid pannus. Carpal instability and navicular-lunate dissociation also accompany pyrophosphate arthropathy, resulting from calcific deposition and cystic degeneration of ligamentous structures.

Adult↗
PubMed1984

Studies on the clearance of calcium pyrophosphate crystals from facsimile synovium.

Calcium pyrophosphate dihydrate crystals have been injected into the air pouch model of facsimile synovium. At various time intervals after crystal injection both infiltrating exudate cells and lining tissue were examined for the presence of crystalline material. The results show that the crystals are initially engulfed by mononuclear cells and to a lesser extent by polymorphonuclear cells in the exudate. Later, crystals became embedded in the lining tissue either within mononuclear cells or as crystal masses confined within granulomas. These studies suggest that the mesenchymal cells ( facsimile synovium) lining rat air pouches can clear calcium pyrophosphate dihydrate crystals from the air pouch cavity. It is therefore inferred that crystals found in the lining of human joint synovium may be incorporated therein by a similar mechanism.

Air↗
PubMed1991

Survival of calcium pyrophosphate crystals in stored synovial fluids.

Eleven synovial fluids containing calcium pyrophosphate dihydrate (CPPD) were examined repeatedly over an eight week period to assess whether storage conditions and duration influenced the number of crystals present. Aliquots of each fluid were stored at room temperature, 4 degrees C, and -70 degrees C. At -70 degrees C there was no change in crystal count after eight weeks' storage. At room temperature and 4 degrees C crystal counts declined slowly over the eight week period, though CPPD crystals were still readily apparent after eight weeks in 10/11 (4 degrees C) and 8/11 (room temperature) fluids. No change in crystal morphology was detected and, apart from one fluid kept at room temperature in which fungal hyphae were noted at six weeks, no new crystals were seen. Calcium pyrophosphate dihydrate crystals in synovial fluid can be maintained for prolonged periods by freezing.

Calcium Pyrophosphate↗
PubMed1984

Emission computed tomography with technetium-99m pyrophosphate for delineating location and size of acute myocardial infarction in man.

Emission computed tomography with technetium-99m pyrophosphate was used to delineate the location and estimate the size of myocardial infarcts in 20 patients with documented acute myocardial infarction. Tomography was performed after planar imaging within 2-5 days after the onset of infarction. A series of transaxial, frontal, and sagittal tomograms were reconstructed from 32 views imaged from the left side of the patient's chest with a rotating gammacamera. Infarct volume was measured from the tomographic images by computerised planimetry and was compared with the cumulative release of creatine kinase MB isoenzyme. The planar images showed discrete myocardial uptake in 13 of the 20 patients and diffuse uptake throughout the cardiac region in the remaining seven. In contrast, the tomographic images clearly delineated discrete myocardial uptake by avoiding confusion of myocardial activity with that of surrounding structures, particularly bones, in all patients. For the 10 patients whose infarct size was assessed by analysis of the creatine kinase MB curve there was a close correlation between infarct volume estimated by tomography and by cumulative creatine kinase MB release. Thus emission computed tomography can provide a three dimensional map of technetium-99m pyrophosphate distribution within the heart and is thus able accurately to localise and estimate the size of myocardial infarcts in man.

Adult↗
PubMed1988

Muscle necrosis in the extremities: evaluation with Tc-99m pyrophosphate scanning--a retrospective review.

A retrospective review was done of 34 extremities studied between 1981 and 1985 with technetium-99m pyrophosphate scanning; 22 were subsequently amputated. Results of detailed pathologic examination or immediate postoperative examination of the resected extremity were available in 16 cases. In these cases, scanning had allowed correct prediction of the level of amputation and of the specific areas of muscle infarction in 13 cases. In the one case in which amputation was performed for infection rather than muscle necrosis, the lack of necrosis was correctly predicted with the scan. The limited results of this study indicate that the Tc-99m pyrophosphate scan allows the location of necrotic muscle to be predicted accurately and may therefore be a useful adjunct in determining the best level for ultimate amputation. Special caution is required in those cases in which muscle necrosis is due to acute causes (e.g., traumatic thrombosis) rather than chronic vascular disease.

Amputation, Surgical↗
PubMed2005

Adult hypophosphatasia and a low level of red blood cell thiamine pyrophosphate.

OBJECTIVE: To report the first adult case of hypophosphatasia and absence of intestinal alkaline phosphatase (ALP) isoenzymes associated with a low level of red blood cell thiamine pyrophosphate. METHODS: We describe the clinical manifestation and laboratory findings in our patient and discuss underlying factors that potentially contribute to her condition. RESULTS: A 33-year-old Vietnamese-American female was referred for a long history of low levels of serum ALP and absence of intestinal ALP isoenzyme. She had a normal level of urinary phosphoethanolamine and a high level of plasma pyridoxal-5p-phosphate. She was found to have a low level of red blood cell thiamine pyrophosphate. CONCLUSION: Our adult case of hypophosphatasia presented with an absence of intestinal ALP isoenzyme that might result in decreasing the absorption of thiamine in the intestinal tract. Therefore, the thiamine level should be considered in hypophosphatasia with absence of intestinal ALP isoenzyme.

Adult↗
PubMed1983

Tibial stress fracture in pyrophosphate arthropathy.

Five elderly patients with chronic pyrophosphate arthropathy developed stress fractures of the tibia. All patients had deformed, painful knees with the result that their increasing symptoms were not readily attributed to a stress fracture. Such a possibility should be considered in patients with chronic pyrophosphate arthropathy since early recognition makes management of the stress fracture easier.

Aged↗
PubMed1986

Technetium-99m pyrophosphate imaging in acute renal failure associated with nontraumatic rhabdomyolysis.

Technetium-99m pyrophosphate (Tc-PYP) imaging was performed in five patients with acute renal failure associated with nontraumatic rhabdomyolysis. Four patients had phencyclidine intoxication and one had viral pneumonia. During the acute phase, marked uptake of pyrophosphate was seen in all patients in several muscle groups, but always in the thigh adductors. The results show that phencyclidine intoxication can result in diffuse muscle uptake of Tc-PYP without overt evidence of muscle injury. Tc-PYP imaging may provide a clue to the cause of acute renal failure in patients with suspected rhabdomyolysis in whom elevations of serum creatine phosphokinase concentrations are equivocal.

Acute Kidney Injury↗