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 and calcium metabolism was investigated in genetically obese, diabetic db/db mice and compared with that in a new hypoglycemic agent (AS-6) treated db/db mice and in their lean litter mates as controls. The 5-week-old db/db mice (serum Ca 9.88 +/- 0.22 mg/dl, glucose 258.6 +/- 13.3 mg/dl) were randomly divided into two groups. One group, together with their lean litter mates, was fed a commercial diet (CE-2). The other db/db group was fed CE-2 diet containing 0.1% of AS-6. Both groups were fed for 20 weeks. The serum glucose and calcium levels in db/db control groups (serum Ca 12.3 +/- 0.1 mg/dl, glucose 650.2 +/- 23.9 mg/dl) were higher than those in lean control groups (Ca 9.8 +/- 0.2 mg/dl, glucose 180.7 +/- 10.1 mg/dl). The wet, dry and ashed weights of the femur in db/db control were significantly lower and the length of femur in db/db control was significantly shorter than those of lean controls. These data suggest that retarded bone growth in db/db mice is related to progression of diabetes. Although, there was no change in Ca/P, Ca/ash and total perimeter in femurs, the cortical area in the femurs of db/db control mice (0.65 +/- 0.02 mm2) was significantly smaller than that of the femurs of lean control mice (0.74 +/- 0.02 mm2). The cortical bone thinning observed in the db/db control could have been caused by increased bone resorption. Treatment with AS-6 for 20 weeks resulted in a 48.6% decrease of serum glucose and 5.2% decrease of calcium as compared with db/db controls.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Altered bone metabolism in db/db mice]. 143 49

Some structurally related chlorinated hydrocarbons were investigated for their effects on the production of prostaglandins by the eggshell gland mucosa of ducks and domestic fowl. Formation of PGF2 alpha, PGE2 and TxB2 by homogenates of domestic fowl eggshell gland mucosa was significantly inhibited by in vitro addition of p,p'-DDE, Arochlor 1242 and, to a lesser extent, Arochlor 1260, but not by p,p'-DDT and o,p'-DDE. Comparatively, in duck eggshell gland mucosa homogenates, synthesis of the same prostaglandins was somewhat more sensitive to inhibition by 5 microM p,p'-DDE added in vitro. Eggshell gland mucosa synthesized significantly more PGF2 alpha, PGE2 and TxB2 than did the mucosa of the magnum and isthmus regions of the oviduct. Duck eggshell gland mucosa homogenates synthesized significantly more prostaglandins than similar homogenates from the domestic fowl, and, considering the former synthesis of PGF2 alpha was significantly higher when ducks were slaughtered at 08:00 than at 16:00 hours. In ducks, dietary administration of 40 ppm, p,p'-DDE for 45 days resulted in 21% eggshell thinning compared to the contemporary control values. This treatment also resulted in notable effects in homogenates of the eggshell gland mucosa, as compared to controls: Ca2+ uptake was reduced by 43%, synthesis of PGF2 alpha, PGE2 and TxB2 was reduced by 26%, 38% and 53%, respectively; the Ca content was increased to 145%. The role of p,p'-DDE in inhibiting prostaglandin formation in the eggshell gland is discussed as a mechanism of the eggshell thinning action of this chlorinated hydrocarbon.
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PMID:Effects of p,p'-DDE and some other chlorinated hydrocarbons on the formation of prostaglandins by the avian eggshell gland mucosa. 144 3

In young women chronic use of luteinizing hormone releasing hormone (LHRH) agonists such as buserelin to treat endometriosis leads to estrogen-deficiency bone loss. Tamoxifen citrate is an estrogen agonist/antagonist which protects the skeleton from osteopenia when ovarian hormones are depleted. The present study was undertaken to determine whether tamoxifen citrate (20 mg/kg body wt/week s.c.) could prevent the osteopenic effect of buserelin (25 micrograms/kg body wt/day s.c.). Four groups of rats with 45Ca-labelled bones were studied for 4 weeks: group A--placebo controls; group B--buserelin; Group C--tamoxifen; group D--buserelin+tamoxifen. Bone resorption was monitored by measuring the urinary excretion of 45Ca and hydroxyproline. Interestingly buserelin lowered both blood 17 beta-estradiol values and uterine weights in the presence and absence of tamoxifen. However, tamoxifen slowed bone breakdown and inhibited the bone-thinning effects of buserelin. Total body calcium values (mg; means +/- S.D.) were: 2227 +/- 137; 1926 +/- 124; 2233 +/- 94 and 2268 +/- 163, in groups A to D respectively. Osteopenia was thus present only in group B (P less than 0.001). Because tamoxifen inhibits estrogen-deficiency bone loss in buserelin-treated rats without depressing the hypoestrogenic actions of this LHRH-agonist, we suggest that use of tamoxifen to protect the skeleton during LHRH-agonist therapy in young women should be explored. Tamoxifen citrate might also help to prevent postmenopausal osteoporosis.
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PMID:Tamoxifen in the rat prevents estrogen-deficiency bone loss elicited with the LHRH agonist buserelin. 152 95

Bone loss associated with sustained administration of luteinising hormone releasing hormone (LHRH) agonists, such as buserelin, is attributed to estrogen deficiency. However, the possibility that the LHRH agonists themselves may contribute to the pathogenesis of bone thinning, has not been ruled out. The aim of the present study was to determine whether or not oral 17 beta-estradiol (300 micrograms/kg body wt/week) would fully prevent the osteopenic effect of buserelin (25 micrograms/kg body wt/day s.c.) in the rat. Four groups of animals with 45Ca-labelled skeletons were studied for 4 weeks: group 1, placebo controls; group 2, 17 beta-estradiol; group 3, buserelin; group 4, 17 beta-estradiol + buserelin. Buserelin alone lowered blood estradiol concentrations, increased bone resorption and reduced femur and total body calcium and 45Ca values. Total body calcium values (means +/- SD) were: (mg) 3405 +/- 176; 3250 +/- 282; 2813 +/- 133; 3156 +/- 452 in groups 1 to 4, respectively. Significant osteopenia was present only in group 3 (P less than 0.001). These results support the view that buserelin-mediated bone loss is due to estrogen deficiency. They do not indicate that LHRH agonists per se, play any role in causing bone thinning.
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PMID:17 beta-estradiol protects rats from osteopenia associated with administration of the luteinising hormone releasing hormone (LHRH) agonist, buserelin. 190 69

Two case reports from a high fluoride (10 ppm) rural community. They presented with severe degrees of dental fluorosis, hyper-sensitivity of teeth and skeletal fluorosis all arising from the ingestion of high amount of fluoride in water over a long period of time. Both cases had deformities of the upper and lower limbs. However, the deformities were more pronounced in the lower limbs than in the upper limbs, resulting in knock knee. Radiological finding showed osteosclerosis of the axial bones while the appendicular bones exhibited osteoporosis. There was marked change of bone structure observed as osteomalacia, and course trabecular bone pattern. Osteoporosis was also associated with cortical thinning. Periosteal bone apposition was observed in the bones: and genu valgum of the limbs. Biochemical tests revealed normal values for serum calcium and inorganic phosphate. However, the serum alkaline phosphatase was elevated. This may be an indication of a pathological condition where there are possible compensatory mechanisms to maintain normal levels of serum calcium and inorganic phosphate. One case which had undergone corrective surgical intervention of the lower limbs four years earlier, had continued to live in the same environment using drinking water with 10 ppmF after corrective surgery, and showed no improvement.
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PMID:Skeletal and dental fluorosis: two case reports. 191 81

To assess the effects of left ventricular chamber volume on the mechanism of changes in left ventricular developed pressure we performed phosphorous-31 nuclear magnetic resonance spectroscopy, hydrogen-1 nuclear magnetic resonance spectroscopy with a shift reagent, two-dimensional echocardiography, atomic absorption spectrophotometry, microsphere analysis, and surface fluorometry on isovolumic isolated perfused rat hearts with incremental intraventricular balloon volumes, while left ventricular pressure was concurrently monitored. A three-phasic response of developed pressure was noted: 0 to 100 microliters balloon volumes resulted in an increase in developed pressure, whereas developed pressure remained constant at 250 microliters and fell at 400 microliters. Oxygen consumption and [Ca2+]i transients followed the same pattern as developed pressure and coronary flow. Intraventricular volumes of 250 microliters or greater (a volume overload) caused endocardial ischemia, a greater decrease in extracellular versus intracellular water, thinning of the left ventricular free wall, and an increase in chamber size. Mechanical pressure on the tissue, induced by the volume overload, caused ischemia as further evidenced by (1) a negative effect on developed pressure, (2) a decrease in [Ca2+]i transients, (3) a [Ca2+]i overload, (4) a moderate decrease in the phosphorylation potential, and (5) an increase in the oxidation-reduction state (nicotinamide-adenine dinucleotide). The high intracellular calcium associated with volume overload may have been due to both compression and ischemia, which leads to an increased number of cross-bridges in rigor, a high end-diastolic pressure, and an increase in wall stress.
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PMID:Mechanism for depressed cardiac function in left ventricular volume overload. 199 Jul 59

To study the pathophysiology of bone disorder after gastrectomy, 320 patients and 40 Wistar male rats were used. Clinically, patients who had received gastrectomy 1-15 years previously, were examined for skeletal symptoms, serum biochemistry, microdensitometry of second metacarpal bone, and 20 of them were then studied in a calcium infusion test. Using microdensitometry, abnormality of bone metabolism was observed in 38% of the patients. In severe cases, a significant decrease of serum Ca. and increase of alkaline phosphatase were observed (p less than 0.05), 65% complained of joint pain. In the calcium infusion test, severe cases showed a low urinary excretion of Ca, like osteomalacia, and unlike osteoporosis. Experimentally, body weight & amount of food intake decreased and fatty diarrhea was observed in rats after total gastrectomy. Skeletal changes including thinning of the cortex, loss of medullary trabeculation & decrease of bone ash and biochemical changes such as low serum Ca. 25(OH)D3, 24, 25(OH)2D3 and high iPTH levels were observed. Also the bone formation rate was lower than control as detected by tetracycline double labelling method. As low food intake & fatty diarrhea after gastrectomy which result in Ca. & vit. D insufficiency may be the major etiology of bone disorder.
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PMID:[Bone disorder after gastrectomy--clinical & experimental studies]. 226 41

Prolonged depression of segmental systolic thickening after brief coronary artery occlusion may result principally from events during reperfusion rather than during the ischemic interval. Thus, cellular calcium overload at reperfusion may be a mediator of contractile dysfunction after brief ischemia, and reduction of calcium entry by diltiazem, a calcium channel antagonist, may enhance recovery of systolic thickening after brief periods of ischemia. Thirteen awake unsedated dogs instrumented with hemodynamic catheters, left anterior descending coronary artery occluders and five to six pairs of intramyocardial sonomicrometers underwent two 15 min coronary artery occlusions with 24 h reperfusion. The order of infusion of diltiazem (15 micrograms/kg per min) or saline solution was alternated. Systolic thickening, hemodynamic variables and regional myocardial blood flow were measured serially over 24 h. Despite equally severe ischemic dysfunction during coronary occlusion, diltiazem-treated segments with systolic thinning during ischemia recovered control segmental thickening significantly earlier than saline solution-treated segments (at 30 versus 180 min of reperfusion). Blood pressure was mildly decreased during diltiazem treatment; therefore, a second group of 10 dogs underwent a similar occlusion and reflow period during infusion of nitroprusside to lower mean arterial pressure equivalently. Decreases in blood pressure in this group resulted in some improvement in segmental systolic function; however, this did not reach statistical significance at any time. Regional myocardial blood flows were similar in the saline solution- and diltiazem-treated groups during ischemia and reflow. Thus, it is concluded that 1) diltiazem infusion significantly enhanced recovery of segmental systolic thickening after 15 min of ischemia and 24 h of reperfusion; 2) the enhancement in segmental systolic function could not entirely be attributed to decreased mean arterial pressure; 3) improvement in postischemic segmental ventricular function was seen only in those segments with systolic thinning during ischemia; thus, segments with the most severe ischemic dysfunction benefited most; and 4) there were no important differences in regional myocardial blood flow during ischemia and reperfusion between saline- and diltiazem-treated animals.
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PMID:Differential enhancement of postischemic segmental systolic thickening by diltiazem. 230 44

Measurements by scanning electron microscopy (SEM) of femoral hemisections confirmed and amplified results by single-photon absorptiometry that had shown a marked increase in lactation osteopenia in rats fed a low-calcium diet (LCD, 0.04% Ca) as compared with a medium-(adequate) calcium diet (ACD, 0.4% Ca). SEM of bones from rats at the end of lactation on either diet showed a large loss of trabecular bone, increased porosity of endosteal surfaces, and cortical thinning. These changes were much more striking in LCD rats than in ACD rats. Backscattered electron imaging of cross sections of the femora revealed marked cortical thinning at midshaft after lactation, especially in rats on the LCD; this method also showed a marked increase in newly formed, less dense diaphyseal bone on the endosteal surface when dietary calcium had been made available to the LCD rats after lactation ceased. Unlike the rats fed the ACD after lactation, the rats continued on the LCD for the first 3 weeks postlactation failed to recover bone mineral, even though there was a marked decrease in resorbing surfaces of the femora as revealed by morphologic examination. When the diet was changed from the LCD to the ACD for the second 3 weeks postlactation (week 4-6), the bone mineral increased substantially. Overall, these results demonstrate the marked loss of bone during lactation, especially severe in rats fed a low-calcium diet, and the rapid postlactational recovery of bone when adequate dietary calcium was made available, even if the recovery had been delayed for the first 3 weeks by feeding a diet very low in calcium.
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PMID:A scanning electron microscopic and photon absorptiometric study of the development, prolongation, and pattern of recovery from lactation-induced osteopenia in rats. 231

Spontaneous fractures were reported to be rare (less than 1%) in 1664 hospital admissions for hip fracture in the 1950s in Sweden. We report 11 fluoride-treated postmenopausal patients who developed spontaneous fractures of the femoral necks, all subcapital initially. In 7 patients who continued treatment there were later femoral neck or shaft fractures; in 6, these were bilateral (one followed a fall). In all there were 19 spontaneous fractures: 5 were asymptomatic, including 2 with deformity; 12 fractures required surgery. Five were incomplete (stress) fractures. All were treated with supplementary calcium 1 g daily; 10 had vitamin D supplementation. In all patients where the timing was known, the initial and subsequent fractures were preceded by, or associated with increased bone turnover as measured by plasma alkaline phosphatase (pAlP) (i.e., they were all "good responders"). Two had pretreatment hip fractures following falls. We compared these 11 (Group 1) and another identically treated group of 14 patients (Group 2), without spontaneous femoral fractures and not different in mean age, pretreatment vertebral fractures, years since menopause, fluoride dosage, and plasma creatinine. Group 1 had a lower (p less than 0.05) index of cortical bone in the femoral neck, as assessed by the ratio "calcar width/femoral neck minimum width." The 6 biopsied fluorotic patients from Group 1 had a higher (p less than 0.05) bone fluoride content than the 4 biopsied fluorotic patients from Group 2. Furthermore, histological cortical features of thinning, increased porosity, and advanced tunneling resorption characterized Group 1 posttreatment biopsies. There were no significant differences in peak pAlP responses in the two groups. Mild asymptomatic vitamin D excess may have been a contributing factor in three Group 1 patients. Two further treatment groups have been studied more recently by forearm single-photon absorptiometry (SPA) at two sites; a cyclic NaF group (Group 3) and a calcium +/- vitamin D group (Group 4). Neither showed significant changes in forearm cortical bone density on treatment for 2 and 1.5 years, respectively, but Group 3 showed a significant increase in density at an ultradistal (60% trabecular) site. The pAlP response in Group 3 was significantly less than in Group 1. Spontaneous femoral neck or shaft fractures did not occur in either Groups 3 or 4. Therefore, we recommend: (1) Avoidance of sodium fluoride (NaF) treatment if pretreatment femoral fracture or thin femoral neck cortices exist.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Spontaneous hip fractures in fluoride-treated patients: potential causative factors. 233 31


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