Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CALCIFICATION”

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 937 records · Page 52Linked to original sources
PubMed1990

Pattern of cardiac calcification in tropical endomyocardial fibrosis.

Over a two-year period we investigated 55 patients with endomyocardial fibrosis, using two-dimensional echocardiography, color-coded echocardiography, and image intensifier fluoroscopy, to delineate the regional distribution of cardiac calcification. Thirty five patients (64%) were found to have calcification of the ventricular walls. Calcific deposits were seen in the right ventricle in 26(59%) patients and in the left ventricle in 16(44%) patients. All patients who showed calcification were in severe cardiac failure indicating late stage of the disease. When image intensifier fluoroscopy was taken as the gold standard, echocardiography had a sensitivity of 100% and a specificity of 98% in detecting cardiac calcification. The high incidence of calcification in the ventricular walls in the present study is apparently due to the systematic use of two-dimensional echocardiography and image intensifier fluoroscopy.

Adolescent↗
PubMed1990

Inhibition of ectopic calcification of glutaraldehyde crosslinked collagen and collagenous tissues by a covalently bound diphosphonate (APD).

Calcification of collagen-derived prosthesis, such as glutaraldehyde crosslinked porcine heart valves or heart valves assembled out of bovine pericardium, presents a major clinical problem. Their subcutaneous implantation into young rats provides us with a reproducible method of assessing this form of ectopic calcification. Long-term implantation is essential, since some materials which do not calcify within the first month frequently exhibit a delayed calcific response. Crosslinked pericardium is much more likely to calcify than crosslinked tendon or reconstituted crosslinked pepsin extracted bovine type I collagen. The covalent binding of a diphosphonate to collagen and collagen-rich tissues can prevent calcification. The binding of this diphosphonate and its ability to inhibit calcification can be enhanced by increasing the number of amino groups on the collagen molecule. The degree of calcification is inversely related to the number of diphosphonate molecules covalently bound to collagen. Under standard conditions, chemical modifications appear to occur primarily on the surface of the collagen fibrils, as evidenced by the relationship between the number of molecules of APD bound and fibril diameter. The bound diphosphonate seems to interfere with crystal growth and prevent the formation of highly insoluble hydroxyapatite on the surface and interstices of the collagen fibrils.

Animals↗
PubMed1990

Soft tissue calcification treated with local and oral magnesium therapy.

Eighty patients with soft tissue calcification were treated: 24 suffered from myositis ossificans traumatica, 23 from calcific bursitis (Duplay's disease), six from osteoarthropathy of elbow joint after severe craniocerebral trauma, nine from calcification around the elbow joint after local trauma, 13 from calcification around the hip joint, and five from calcification in ligaments and tendons. Using a new method of treatment about 75% of patients were cured. Calcifications disappeared or diminished substantially. Very good functional improvement followed in affected joints. The treatment involved local application of MgSO4 under local anaesthesia into calcified areas for 2-20 weeks, together with peroral administration of Mg lactate for 4-6 months. There were no complications or side effects of this treatment.

Administration, Oral↗
PubMed1989

[Correlation between the sites of mitral annular calcification and conduction disturbances: echocardiographic evaluation].

A clinical, electrocardiographic and echocardiographic (M-Mode, 2D) study was performed to explain the causal relationship between mitral annular calcification and cardiac conduction disturbances. Forty-seven patients, 28 women and 19 men (mean age 69) with mitral annular calcification were studied. In 18 patients A-V and/or intraventricular conduction disturbances were present. In this study we have found: a greater incidence of posterior than anterior mitral annular calcification; the anterior mitral annular calcification is often associated with aortic valve calcification and ultimately the common association between anterior mitral annular calcification and conduction disturbances.

Aged↗
PubMed1989

[Investigation on calcifications in the breast].

This article reported the result of analysis of 96 cases with heaps of calcifications in the breast all verified by operation. The calcifications, according to the appearances on X-ray film were classified into 4 patterns: club-shaped, fine sandy, fragmented stonelike and coalescent. A comprehensive analysis was made in regard to spatial distribution and amount of calcification and the presence of a mass. The results indicated that club-shaped calcification is highly suggestive of malignancy regardless of the amount of calcification and the presence or absence of a mass. Simple fine sandy calcification in the absence of a mass can not differentiate benign from malignancy because of wide range of overlapping, whereas simple fragmented stone and coalescent types, according to the authors opinion denote benign.

Adenofibroma↗
PubMed1989

[Radiographic examination of the thorax, fluoroscopy and echocardiography in cardiac calcification].

The value of radiographic examination of the thorax, fluoroscopy and echocardiography in demonstration and localization of intracardiac calcifications were compared in an investigation of 40 patients with valvular heart disease prior to planned cardiac catheterization or operation. Radiographic examination of the thorax revealed only the most severe calcifications. By means of echocardiography it proved possible to undertake a simple semi-quantitative characterisation of the calcified tissue with acceptable intra- and inter-observer variation. Echocardiography and fluoroscopy were found to be of equal value in demonstration of the degree of calcification of the heart. Echocardiography was, however, superior to fluoroscopy in fine localization of the calcifications. The relative and additive values of the methods could be illustrated employing Bayes' theorem and could be represented graphically provided that the observations carried out with the three methods could be considered independent of one another. It is concluded that radiographic examinations of the thorax is unsuitable for screening for cardiac calcifications. Fluoroscopy can no longer be considered to be the method of choice in assessing lesions of this type but should be employed in cases where echocardiography does not provide sufficient information or is not available. The greatest certainty in demonstration of calcifications is obtained with combined employment of fluoroscopy and echocardiography.

Adult↗
PubMed1989

[Unusual calcification in brain suspected to be caused by toxoplasmosis: a report of an autopsy case].

A very rare case of severe calcification in brain is reported. A 49-year-old man was hit and run by a motorcar in acrossing a road on foot, and he died 1 hour later in an emergency hospital. Medico-legal autopsy was done at 5 hours after his death. The cause of death was cerebral contusion caused by a struck on partieto-occipital region. Unusually severe calcification was observed in the right and left cerebral hemispheres, especially basal ganglia, in the border areas between grey and white matters of frontal, parietal and occipital lobes, as well as in the cerebellar nucleus, cortex and medulla. Histological examination showed severe multiple calcification in the brain tissue. Dispersed deposit of pseudocalcium-Ca and edema were observed around the calcifications. Proliferation of glia cells and decrease of nerve cells were also noted. In his past history, he began to speak distinctly and to stagger since 8 years ago. Three years ago, he collided with guardrail while driving his motorcycle, and he was hospitalized. Calcification in the brain was already revealed in the roentogenographic examination. In the laboratory findings, the data of serum calcium, serum phosphorus and Ellsworth-Haward test were normal. The antibody of toxoplasma, however, showed high level more than X 1,024. After he was discharged, dementia, instability of trunk and dysarthria still continued, and he used to across a crowded road unconcernedly. The cause of the calcification might be suspected to be toxoplasmosis, although neither trophozoites, cysts nor oocysts were found in the brain tissue.

Accidents, Traffic↗
PubMedDate not supplied

[Study of calcification of the mitral annulus. Importance of echocardiographic analysis].

Mitral annulus calcification is a common finding in old people. In order to know the association of mitral annulus calcification with other pathologic conditions, 25 patients were studied by echocardiography, 20 females and 5 males. No significant differences _ere observed with respect to sex. The average age was 67 +/- 15 years. Mitral annulus calcification was associated with aortic sclerosis in 100% of the cases, to arterial hypertension in 19 (76%), to obstructive pulmonary disease in 8 (32%), to diabetes mellitus in 5 (20%), and to peripheral arterial insufficiency in 5 (20%). Mitral regurgitation was found in 14 cases, atrial fibrillation in 2 (8%). Complete A-V block was not observed, but there was enlargement of the left ventricle in 23 (92%) and of the left atrium in 17 (68%). The chest X-ray showed mitral annulus calcification in 5 (20%) with a sensitivity of 25% and a specificity of 100%. The M-mode echocardiogram showed LA-Ao ratio of 1.4 +/- 0.3, the mitral valve D-E excursion was reduced 11.9 +/- 3.1 mm. and also the E-F slope 28.6 mm/seg +/- 16.7 with appearance of mitral stenosis, but the two-dimensional study demonstrated that this was false. In all patients the left ventricle was dilated and fractional shortening was diminished. Echocardiography not only is a good diagnostic method for mitral annulus calcification, it also allow us to evaluate the hemodynamic consequences of this pathology which occurs in older patients and is often associated with other common illnesses of advanced age. In our study 56% of mitral annulus calcification cases were associated with mitral regurgitation.

Aged↗
PubMed1987

The role of glutaraldehyde-induced cross-links in calcification of bovine pericardium used in cardiac valve bioprostheses.

Calcification is the principal cause of failure of tissue-derived cardiac valve replacements pretreated with glutaraldehyde (GLUT). The objective of this study was to determine the role of GLUT-induced cross-links in bovine pericardial tissue calcification. Various levels of 3H-GLUT incorporation were obtained by varying incubation pH, and protein modification was determined by amino acid analysis and resistance to collagenase digestion. Calcification of cross-linked tissue was studied using subdermal implants in rats. Low GLUT uptake (less than 150 nm/mg) resulted in minimal calcification (Ca2+, 12.8 micrograms/mg) and stability (4% residual weight following digestion) due to a limited crosslinking (lysine + hydroxylysine = 26.1 residues/1000 amino acids [AA]). In contrast, higher GLUT uptake induced more cross-links (Lys + Hyl = 8.2 residues/1000 AA) and consequent higher stability (95% residual wt); such tissues calcified severely (Ca2+, 93.5 micrograms/mg). Incorporation of GLUT two to three times beyond a critical level did not further enhance calcification. It is concluded that the amount of GLUT incorporated controls the extent of cross-links, which in turn directly determines tissue stability and calcification.

Aldehydes↗
PubMed1987

Prevention of leaflet calcification of bioprosthetic heart valves with diphosphonate injection therapy. Experimental studies of optimal dosages and therapeutic durations.

Ethanehydroxydiphosphonate therapy was studied for prevention of calcification of bioprosthetic heart valve cusps (from glutaraldehyde-preserved porcine aortic valves) implanted subcutaneously in 3-week-old male rats. Animals received daily subcutaneous injections of the drug (1, 5, 10, 15, or 25 mg/kg/24 hr) for 21 days with maximal inhibition of bioprosthetic heart valve calcification at a dosage of 15 mg/kg/24 hr (calcium level of diphosphonate-treated bioprostheses 3.5 +/- 0.5 micrograms/ml; calcium level of control bioprostheses, 161.2 +/- 5.0 micrograms/mg), but with irreversibly diminished bone and somatic growth. A dosage optimum was observed at 10 mg/kg/24 hr with significant inhibition of bioprosthetic heart valve calcification (at 21 days, the calcium level was 16.4 +/- 3.6 micrograms/mg) and an absence of adverse effects on epiphyseal development and overall growth. Bioprosthetic heart valves retrieved from animal receiving ethanehydroxydiphosphonate (15 mg/kg/24 hr) for only the first week after implantation had significantly more calcification after 21 days than did bioprostheses from animals treated for 2 or 3 weeks. Bioprostheses explanted after 110 days from animals receiving the drug (15 mg/kg/24 hr) for the first 3 weeks had calcification equivalent to that of untreated control rats. Diphosphonate (15 mg/kg/24 hr) was most efficacious when initiated within 48 hours of bioprosthesis implantation, but was totally ineffective if administered after 1 week. It is concluded that ethanehydroxydiphosphonate optimally prevents bioprosthesis calcification without significant adverse effects on epiphyseal development and overall somatic growth at a dosage of 10 mg/kg/24 hr in rat subdermal implants, but it must be administered by continuous daily injections beginning within 48 hours of the implantation; this approach should be pursued in further long-term circulatory experimental studies because of its possible clinical relevance.

Animals↗
PubMedDate not supplied

MR detection of intracranial calcification: a phantom study.

To make a comparative analysis of calcium detection between MR and CT, anhydrous, insoluble calcium carbonate spheres varying in size from 1.5-7.0 mm were embedded in three physiologic tissue phantoms: low-protein gelatin (3 gm%), high-protein gelatin (6 gm%), and heavy mineral oil. The calcium-containing phantoms were scanned by CT and MR, using both T1- and T2-weighted sequences, with a slice thickness varying from 5-7 mm. Partial volume artifacts were determined by abutting phantoms with and without calcium and by varying the slice position to include different proportions of the calcium- and noncalcium-containing phantoms. Contrast-detail curves, expressed as a ratio of contrast to noise, were determined for varying sizes of calcification and degrees of partial voluming. As expected, the CT conspicuity of calcification (positive contrast) markedly surpasses that of MR (negative contrast). The difference was two orders of magnitude. When the calcification filled more than half the slice on MR, the conspicuity depended on the contrast of the matrix material; i.e., increased matrix intensity caused increased conspicuity. However, as the size of the calcification decreased, partial volume effects increased; i.e., increased matrix intensity caused decreased conspicuity. Conspicuity of small calcifications is independent of matrix material, since contrast and partial volume effects balance. We conclude that CT is clearly the method of choice for identifying small foci of calcification.

Brain↗
PubMed1988

[Contribution of microradiography in search of calcifications of valvular bioprostheses].

Implantation of a valvular bioprosthesis is one of the best treatments for valvular disease, particularly in children. Unfortunately, their use is limited as calcifications develop over time. Prevention of these calcifications is still an unresolved problem that is under study by Professor Carpentier and coworkers. These investigators have developed an experimental model in which accelerated development of calcifications occurs: fragments of porcine valves implanted under the skin of rats become calcified in a few days. Prior to implantation, the fragments are pretreated in an attempt to delay or prevent the development of calcifications. Two, four, six and eight months after implantation, the fragments are removed and calcifications are looked for using microradiography. Two hundred fragments have been studied. The material and technique used in our study are described. Results are semi-quantitative, based on the volume of calcifications. We conclude that microradiography is faster and more reliable than histology (the only technique used up till now) as it allows to study the entire fragments.

Animals↗
PubMed1986

[Evaluation of intracranial calcification associated with aging by computerized tomography].

Computerized tomography (CT) scans of 450 standardized normal persons from 5000 consecutive patients were examined to study the relationship between the incidence of intracranial calcification and aging process. The 450 subjects were classified into 9 groups according to age. In people older than 30 years, calcification in the pineal region including pineal body and habenular commissure was found in about 70%. Calcified choroid plexus seems to be characteristic of aging process because the rate of its calcification increased in proportion to aging. Calcification of the falx cerebri was also found to increase in proportion to aging. Calcified cerebral arteries were observed in advanced-aged groups. The fact that people in the ninth decade had a smaller incidence in calcification of the cerebral artery than those in the eighth decade indicates the possibility that longer-lived people had less incidence of cerebral arterial calcification.

Adolescent↗
PubMed1985

Renal osteodystrophy and metastatic calcification in long-term continuous ambulatory peritoneal dialysis.

The biochemical data and drug histories related to bone disease were extracted from the case records of 47 patients who had been treated by continuous ambulatory peritoneal dialysis (CAPD) for more than two years. These data were reviewed in conjunction with the skeletal surveys done over the same period in all patients, with particular reference to secondary hyperparathyroidism, osteomalacia and non-visceral metastatic calcification. Paired bone biopsies were available in 20 of these patients and the histology was quantitated. In the majority of our patients secondary hyperparathyroidism was controlled or improved on CAPD. Osteomalacia also improved in two of the three patients in whom it was initially present and did not develop in any patient whilst on CAPD. We did, however, note a high incidence of non-visceral metastatic calcification. Small vessel calcification developed in 19.6 per cent of patients, large vessel calcification developed in 23.9 per cent and soft tissue calcification developed in 21.7 per cent of patients. We conclude that CAPD, as a form of treatment for end-stage renal disease, satisfactorily controls the osteodystrophy associated with renal failure in the majority of patients. The significance of the high incidence of non-visceral metastatic calcification remains to be established.

Adult↗
PubMed1985

Ectopic calcification. The role of parathyroid hormone.

In 42 uraemic patients radiological skeletal survey, biochemistry and bone histology were compared before and at 6-12 months (42 patients), 12-24 months (26 patients) or 24-48 months (12 patients) after parathyroidectomy. The presence of small vessel or non-visceral soft tissue calcification was not related to the age, sex, duration of end-stage renal failure treatment, total serum calcium, magnesium, phosphate, Ca x P product, alkaline phosphatase, ionised calcium, serum aluminium, iPTH, severity of radiological and histological osteitis fibrosa or parathyroid gland weight. Twenty-three patients (55%) had small vessel and 20 (48%) soft tissue calcification before parathyroidectomy. Despite a marked improvement in subperiosteal erosions (37 healed, 5 improved) and healing of osteitis fibrosa histologically, seven patients developed new and six developed increased peripheral arterial calcification while in 10 patients non-visceral soft tissue calcification disappeared and in two decreased. Successful parathyroidectomy improves non-visceral calcification but not arterial calcification despite reduction in Ca x P product and iPTH.

Adult↗
PubMed1985

[Metastatic pulmonary calcification in patients with chronic renal insufficiency].

Case reports on two patients with metastatic pulmonary calcification are presented. Both suffered from long standing chronic renal failure and received immunosuppressive therapy for a (non-functioning) renal transplant. Laboratory tests disclosed hyperphosphatemia and secondary hyperparathyroidism. In the first patient, who presented with "pulmonary edema", the course was rapidly fatal. Diffuse pulmonary calcification was diagnosed only post mortem. Transbronchial biopsy was diagnostic for calcification in the second patient, who had exertional dyspnea and bilateral, asymmetric, interstitial infiltrations on chest X-ray. In patients with chronic renal failure, metastatic calcifications are due not only to disturbances of calcium-phosphate homeostasis but also to other, mostly unknown factors. Diagnostic procedures include biopsy and 99m-technetium-diphosphonate scintigraphy. Prophylaxis of pulmonary calcifications through normalization of serum phosphate and, if indicated, subtotal parathyroidectomy is of the utmost importance as regression of established calcifications rarely occurs.

Calcinosis↗
PubMed1979

[The echocardiogram in mitral anulus calcification].

In agreement with the known high incidence of mitral anulus calcification in elderly patients, the authors have found corresponding calcifications in echocardiographic examinations in 61 patients as the single or additional cause of an abnormal systolic or diastolic murmur. The intracardiac calcifications were known of from the chest X-ray only in 6 patients. The echocardiograms served to locate and estimate the amount of the calcification. Calcifications of the aortic cusps, found in 75% of patients, may be of degenerative origin. The echocardiographic presentation of the degenerative calcifications can be misinterpreted either as postrheumatic valvular disease, posterior pericardial effusion or hypertrophic cardiomyopathy. Registration by continuous sector scan was necessary to differentiate these entities.

Aged↗
PubMed1977

Pituitary adenoma calcification.

Calcifications have been found in 9 of 137 different pituitary adenomas (6.6%) that have been examined with skull roentgenograms, light microscopy, and electron microscopy. Electron microscopy was most efficient because seven cases showed positive findings. Skull x-ray films showed calcification in four and light microscopy in only two cases. Six adenomas showed signs of increased prolactin production (either by direct determination or presence of galactorrhea). Two pateitns with calcifications on skull x-ray films and negative microscopic examinations did not show signs of any hormone secretion. The ultrastructural examination showed that the process of calcification started in single necrotic cells undergoing fibrillary transformation. No large areas of necrosis were present as seen in other forms of dystrophic calcification. The deposits consisted of dense accumulation of radially oriented hydroxyapatite crystals. The observations suggest that local factors and the type of hormone secreted may play an important role in the calcification pattern of pituitary adenomas.

Adenoma↗