Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bone histology, bone mineral content, and calcium absorption were evaluated in 10 patients with primary biliary cirrhosis and osteopenia, before and after 1 yr of treatment with oral 25-hydroxycholecalciferol. Before treatment, quantitative histomorphometric analysis of full-thickness iliac crest bone biopsy specimens with double-tetracycline labeling demonstrated that 9 of 10 patients had osteoporosis. None had osteomalacia. Fasting intestinal calcium absorption correlated well with trabecular bone volume (r = 0.85). Bone mineral content measured by 125I-photon absorption was low in 6 of 10 patients, and it correlated poorly with iliac crest trabecular bone volume. After 1 yr of treatment with oral 25-hydroxyvitamin D3, bone mineral content fell in all 8 patients who were restudied. Iliac crest trabecular bone volume increased in 3 patients, 2 of whom had the greatest pretreatment impairment in calcium absorption, but fell in 5. Bone fractures continued to occur in 3 of 5 patients who were alive after 1 yr and developed for the first time in a sixth patient. We conclude that 25-hydroxyvitamin D3 is ineffective in reversing the bone thinning in the majority of primary biliary cirrhosis patients, but it may be helpful in a few selected patients.
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PMID:Osteoporosis in primary biliary cirrhosis: effects of 25-hydroxyvitamin D3 treatment. 707 48

Ion etching and thinning using ionized argon beams have been used to prepare surfaces and thin sections of human and animal compact cortical bone for examination in both scanning and transmission modes of the electron microscope. Using these techniques the mineral component in bone is revealed as a continuous, vermiform microskeleton composed of spheroidal segments approximately 0.1 micrometer in diameter. Electron diffraction and micro-analysis have confirmed that the mineral segments contain calcium and phosphate ions arranged in a poorly crystallised form of hydroxyapatite.
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PMID:The spatial arrangement of bone mineral as revealed by ion bombardment. 732 18

We wished to determine whether prolonged therapy with the Ca2+ channel blocker verapamil has beneficial structural and functional cardiac effects. Nine hypertensive outpatients [systolic blood pressure (SBP) 164 +/- 4 and diastolic BP (DBP) 103 +/- 4 mm Hg: men and women, blacks and whites, mean age 48.6 years] received 240-480 mg slow-release verapamil (Calan-SR) a day. BP, left ventricle (LV) wall thickness and mass, and mitral flow characteristics on echocardiography, and plasma catechols and renin were determined at 0, 5, 10, and 15 months. Patients were compared with 10 normotensive controls, of similar group composition (SBP 130 +/- 3 and DBP 82 +/- 1 mm Hg; age 47.2 years). In the hypertensive patients, SBP and DBP decreased significantly (p < 0.05), by 14 and 12 mm Hg, respectively, but remained well above that of controls and > 140/90 mm Hg. Diastolic LV septal thickness decreased from 15.3 +/- 0.6 to 14.5 +/- 1.1 mm (not significant), while diastolic LV posterior wall thickness (PWTd) decreased significantly (p < 0.05) from 15.7 +/- 0.6 to 14.1 +/- 0.7 mm after 8 months, but not to the value of the controls. LV diastolic and systolic and left atrial dimensions remained constant. Normalized LV mass, initially 60% greater than the controls, decreased slightly (11%) but nonsignificantly and remained above that of controls. Neither LV mass nor LV posterior wall thinning was correlated with reduction in BP. Patient peak systolic wall stress was initially significantly lower than that of controls.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Structural and functional myocardial responses to chronic treatment with the Ca2+ blocker verapamil (Calan-SR) in hypertensive patients. 750 68

Manufacturing factors have seldom been implicated as a direct cause of structural deterioration of valvular bioprostheses; this phenomenon has generally been considered to be of a host-dependent origin. We analyzed the clinical and pathologic data from 12 Carpentier-Edwards mitral bioprostheses removed from 12 patients because of severe dysfunction and showing detachment of the porcine aortic wall from the stent in one commissure or more. These 12 prostheses were part of a group of 92 such valves that were explanted and displayed structural deterioration. They belong to a population of 405 Carpentier-Edwards bioprostheses implanted in the mitral position in our institution between May 1978 and November 1988. The patients included three men and nine women with a mean age of 54 +/- 13 years. One patient had a history of chronic renal failure, and two had systemic hypertension. Prosthesis sizes were 29, 31, and 33 mm (n = 4 for each size). The models of the valves were 6625 (n = 8) and 6650 (n = 4). Mean duration of implantation of the prostheses was 99 +/- 27 months (52 to 136 months) and did not differ depending on the model. There was no significant clustering of commissural detachments depending on valve size, year of implantation, or gender of the patient. No similar phenomenon was observed among 76 explanted aortic Carpentier-Edwards bioprostheses with structural deterioration from a population of 441 valves implanted during the same time frame. Native porcine aortic roots (n = 5) and aortic Carpentier-Edwards bioprostheses explanted because of structural deterioration (n = 4) were used as controls for comparison. Macroscopic examination showed single commissural dehiscence in 10 patients and double in two. Radiology disclosed no or mild mineralization in eight valves and no calcium in the area of aortic wall dehiscence, except for heavily calcified valves. Light microscopy evidenced a significant thinning of the aortic wall at the paracommissural level of mitral bioprostheses (351 +/- 68 microns) compared with either aortic bioprostheses (526 +/- 59 microns; p < 0.01) or control native porcine aortic roots (419 +/- 50 microns; p < 0.01). No difference was found in terms of aortic wall thickness between detached (322 +/- 42 microns) and intact (366 +/- 74 microns) commissures in mitral bioprostheses.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Commissural dehiscence of Carpentier-Edwards mitral bioprostheses. Explant analysis and pathogenesis. 756 35

The toxic effects of long-term administration of cadmium (Cd) on the kidneys, liver, and hind leg bones were studied histologically and roentgenologically in 29-day-old female ICR-strain mice separated into groups variously fed 1) a commercial (calcium [1.17%], vitamin D [220IU/100g], vitamin E [10mg/100g]) diet, 2) a low Ca (0.18% diet, 3) a low Ca and low D (50IU/100g) diet, and 4) a low Ca, low D and low E (5mg/100g) diet. Though the levels of vitamin D and vitamin E were designed to be low in each diet, their amounts fulfilled the nutritional requirements. Three subgroups in each category were fed Cd at dietary concentrations of 0, 20 or 40 ppm. After 12, 18 or 24 months on these diets the mice were sacrificed. 1) In the groups fed the commercial diet containing Cd, prominent swelling of the glomerulus and thickening of the basement membrane of glomerulus were observed. This did not occur in the groups fed the commercial diet without Cd. 2) In the groups fed the Cd-added low-Ca diet the following findings were more prominent compared with the low-Ca diet group. In the kidneys, swelling of the glomerulus, hyaline casts in tubular lumina and cellular infiltration of the interstitial tissue were present. In the liver, cellular infiltration on the interstitial tissue were present. In the liver, cellular infiltration of the interstitial tissue occurred. In the hind leg bones, thinning of trabeculae and ossification of the Achilles's tendon were seen. 3) In the Cd-added low-Ca, D diet groups, there was atrophy of glomerulus, thickening of basement membrane of glomerulus, and atrophy of tubular epithelial cells in the kidneys, while in the liver, binuclate cells, anisonucleosis and enlargement of Kupffer cells were seen. In the hind leg bones, thinning of the cortex and trabeculae were present. All of these findings were more prominent in this group than in the low-Ca, group. 4) In the Cd-added low-Ca, D, E, diet groups subjects the following findings were more prominent than in the low-Ca, D, E, diet group. In the kidneys, there was swelling of glomerulus and in the liver, there were binuclate cells, anisonucleosis, and cellular infiltration into interstitial tissue. In the hind leg bones, thinning of the cortex and trabeculae, a decrease of cartilage cells and a decrease of osteocytes were seen. These histological and roentgenological changes were seen to increase in a dose-dependent manner with the amount of dietary Cd.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[The effects of long-term intake of restricted calcium, vitamin D, and vitamin E and cadmium-added diets on various organs and bones of mice: a histological and the roentgenological study]. 763 34

Following prolonged ischemia, if not adequately reperfused, myocardium undergoes necrosis, scarring and thinning. The myocardium tends to dilate in the noninfarcted ventricular area, giving rise to ventricular remodelling. If the ischemic myocardium is adequately reperfused it can be saved and its temporarily depressed functions eventually be recuperated (viable myocardium). The extent of recovery of the postinfarction viable myocardium seems to affect ventricular remodelling. The integrity of the microcirculation of the non-contractile myocardium following prolonged ischemia is fundamental in maintaining a contractile reserve adequate enough for a functional recovery (myocardial viability). Protection of the microcirculation during ischemia-reperfusion is therefore of great importance for the role that the microcirculation plays in ensuring myocardial viability. Experimental studies and initial clinical observations showed that calcium-antagonists exert a beneficial effect in this respect. VAMI is a multicentre, randomized double-blind, placebo-controlled study whose aim is to ascertain the potentiality of verapamil in limiting regional functional damage in patients with acute myocardial infarction and undergoing early thrombolysis.
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PMID:[Myocardial viability in acute myocardial infarction and verapamil]. 763 65

This study was designed to test the effect of natural calcium on the bone loss induced by ovariectomy in rats. Thirty female four-month rats were divided into three groups: sham operated group (Sham), ovariectomized group (OVX) and ovariectomized with calcium supplementation group (OVX + CA). OVX + CA rats were treated with calcium at a dose of 50 mg/kg weight per day for 90 days after surgery. Blood biochemical analysis, bone pathology, bone histomorphometric measurement and bone weight were processed. OVX rats were characterized by thinning, wormerosion like loss of trabecular bones, decreased volume of cancellous bone, increases in osteoblast index and osteoclast index, decreases in wet, dry and ash weights of left femur, and decreases in contents of calcium and phosphorus of bones. Treatment of OVX + p6 rats with calcium provided complete protection against bone loss and significantly depressed bone turnover. Our results indicate that natural calcium is effective in prevention of osteopenia in ovariectomized rats. The authors believe that the main mechanism of calcium against bone loss exists in correction of minus calcium balance, and depression of high bone turnover, especially the absorption action of osteoclasts.
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PMID:[Effect of natural calcium against osteopenia in ovariectomized rats]. 765 44

Despite growing clinical use of transluminal balloon angioplasty (TBA) to treat cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH), the precise mechanism of action of balloon dilation on the cerebral arterial wall is unknown. In this experiment the authors examined the pharmacological and morphological changes in 10 normal and 12 vasospastic canine basilar arteries following in vitro silicone microballoon TBA. For the SAH group in which the double-hemorrhage model was used, vasospasm was confirmed by angiography and the animals were killed on Day 7 after the first SAH. In vitro TBA was performed on basilar arteries from normal and SAH dogs immediately after sacrifice and removal of the brain. The procedure was performed while the arteries were maintained in oxygenated Krebs buffer. In the pharmacological studies, potassium chloride, prostaglandin F2 alpha, serotonin, and noradrenaline were used as vasoconstrictors, and bradykinin and calcium ionophore A23187 were used to produce an endothelium-dependent dilation. In both normal and vasospastic groups, the pharmacological responses of dilated segments of basilar arteries were compared to those of nondilated segments of the same arteries. Vessels from all groups were examined using scanning electron microscopy (EM) and transmission EM. Scanning EM was used to study the intact vessel wall, the smooth-muscle cell layer obtained after digestion with hydrochloric acid, and the extracellular matrix obtained after digestion with bleach. Cross-sections of the vessel wall were examined using transmission EM. The most striking finding was that immediately after in vitro TBA of both normal and vasospastic canine basilar arteries, there was a significant reduction (p < 0.05) of responses to both vasoconstrictors and vasorelaxants. As revealed by scanning EM and transmission EM, both normal and vasospastic vessels dilated with TBA showed flattening and patchy denudation of the endothelium, and straightening and occasional rupturing of the internal elastic lamina. In addition, vasospastic vessels dilated with TBA showed decreased surface rippling and mild stretching and straightening of smooth-muscle cells, and mild thinning of the tunica media. There was no gross vascular disruption or obvious change in the extracellular matrix of the vessel walls of either normal or vasospastic arteries after TBA. These results suggest that functional impairment of vasoreactivity in the vessel wall as a result of mechanical stretching of the smooth-muscle layer plays a more important role than structural alteration, at least in the immediate dilation produced in vasospastic arteries by TBA.
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PMID:Pharmacological and morphological effects of in vitro transluminal balloon angioplasty on normal and vasospastic canine basilar arteries. 766 32

Eggshell formation and egg production in domestic fowl were studied following the administration of methyl mercury (two dose regimes: 5 mg daily for 6 consecutive days and 1 mg daily for 50 consecutive days). A daily oral dose of 5 mg of methyl mercury for 6 consecutive days induced significant eggshell thinning and deformation and inhibited egg production. Uptake of 45Ca and synthesis of prostaglandins by a homogenate of eggshell gland mucosa from methyl-mercury-treated birds were significantly reduced, as was the calcium content of blood plasma. A daily oral dose of 1 mg of methyl mercury administered for 50 consecutive days also induced eggshell deformation and thinning and reduced egg production. This dose did not, however, have significant effects on the following: 45Ca uptake and prostaglandin synthesis by a homogenate of the eggshell gland mucosa; 45Ca uptake by a homogenate of duodenal mucosa; the Ca content of the blood plasma, shell gland mucosa or shell gland lumen; the HCO3- content of the shell gland lumen or the specific gravity of tibia. Methyl mercury added in vitro to a homogenate of eggshell gland mucosa significantly stimulated the synthesis of prostaglandins PGF2 alpha and PGE2. Addition of mercury chloride to the same type of preparation stimulated the synthesis of PGF2 alpha at the expense of thromboxane (TxB2) synthesis. Administration of 5 mg methyl mercury for 6 consecutive days seemed to reduce the availability of calcium for eggshell formation. This effect could have been due to a direct inhibitory effect of methyl mercury on calcium uptake from the gastrointestinal tract and/or to mobilization of medullary bone.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effects of methyl mercury at different dose regimes on eggshell formation and some biochemical characteristics of the eggshell gland mucosa of the domestic fowl. 774 99

Aging and menopause are the two main determinants of osteoporosis, a rarifying osteopathy due to bone loss. Type I osteoporosis observed in post-menopausal women is characterized mainly by trabecular bone loss results from an unbalanced coupling between resorption and formation inducing a thinning of trabeculae and from an increased osteoclast activation resulting in irreversible trabecular perforation. Anti-osteoclastic drugs prevent trabecular and cortical bone loss. Drugs that stimulate osteoblastic proliferation thicken trabecular plates but do not restore the normal trabecular microarchitecture after complete destruction of a large number of trabeculae. In type II osteoporosis, cortical bone loss is favoured by secondary hyperparathyroidism and is responsible for hip fracture. Calcium and vitamin D supplementations decrease the risk of hip fractures by reducing the secondary hyperparathyroidism.
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PMID:[Mechanisms of bone loss in osteoporosis]. 779 29


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