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1.
This study investigated whether hydroxyproline, deoxypyridinoline, or the carboxyterminal telopeptide of type I collagen could be used as markers to provide evidence of bone resorption during hypocalcemia of dairy cows. Serum concentrations of the amino-terminal propeptide of type III procollagen were also analyzed to study the effect of parturition on type III collagen, which is a component of soft connective tissues. Urine and blood samples were collected on d 1 to 5, on d 9, and d 14 after parturition from 18 cows with symptoms of periparturient paresis (group 1) and 19 healthy control cows without symptoms (group 2). Urine concentrations of hydroxyproline and deoxypyridinoline were measured with a colorimetric assay and an enzyme immunoassay, respectively. Serum concentrations of the amino-terminal propeptide of type III procollagen were measured using a commercially available radioimmunoassay. A radioimmunoassay was developed to analyze serum concentrations of the carboxyterminal telopeptide of bovine type I collagen. The mean corrected urinary hydroxyproline concentrations in group 1 increased from parturition to d 14; concentrations in group 1 were significantly higher for group 2 after d 5. Mean corrected deoxypyridinoline concentrations in urine increased after parturition to reach a peak at d 9, and serum concentrations of the carboxyterminal telopeptide of type I collagen peaked at d 5. However, mean concentrations of deoxypyridinoline and the carboxyterminal telopeptide of type I collagen did not differ significantly between groups. The variation in the behavior of the three markers is likely a reflection of the different phases and aspects of the bone collagen degradation. In conclusion, assays for urinary deoxypyridinoline and serum carboxyterminal telopeptide of type I collagen determinations are useful tools to follow the course of degradation of bone collagen in dairy cows.  相似文献   

2.
Previous studies on the relation between moderate physical activity and bone mass have observed conflicting results. Many of these studies have not dissociated the role of physical activity by age groups and in relation to the period of peak bone mass formation. Our cross-sectional analysis of the baseline data of a longitudinal study of 273 women aged 21-40 attempted to evaluate the role of moderate physical activity on bone mass around the period of peak bone mass attainment. The analyses were carried out separately for the two age groups--21-30 and 31-40--and had also taken into account the effects of age, dietary calcium intake, and lean body mass on bone mineral density (BMD). The total metabolic equivalent values (MET) of leisure time physical activity was based on the MET values for each activity and the reported time spent on each activity in the past year. The results indicated that among the younger group of women, high level of leisure time physical activity was associated with higher bone mass at both the spine and the hip. Additive effects of physical activity and dietary calcium intake on the spine and the hip BMD were observed. Together with age and lean body mass, physical activity and dietary calcium intake accounted for 19% of the variances of bone mineral at the spine and 9-11% at the hip. Among women aged 31-40, presumably after the peak bone mass formation, lean body mass as well as fat mass have independent strong association with BMD. Physical activity was not associated with bone mass in this age group.  相似文献   

3.
A case of measles in a 26-year-old Japanese man is reported. A skin specimen taken on the third eruptive day from a maculopapular eruption on his chest was immunohistopathologically and electron microscopically examined using a rabbit polyclonal antibody against the nucleocapsid protein of the measles virus. The measles virus antigen was found in the inner cells of the acrosyringium and hair follicles. The measles virus nucleocapsid was electron microscopically identified in the nuclei of the inner cells of the acrosyringium. The findings suggest that the sweat from skin lesions might contain the measles virus.  相似文献   

4.
Collagen type 1 represents more than 90% of bone matrix. Therefore, quantitation of collagen crosslinks, such as deoxypyridinoline, can provide information on bone resorption degree. An evaluation was made of deoxypyridinoline as well as other bone markets, such as alkaline phosphatase, tartrate resistant acid phosphatase, and hydroxyproline in patients with the diagnosis of osteoporosis. Paget's disease, hyperthyroidism, and chronic renal failure on haemodialysis or not. Deoxypyridinoline levels were significantly increased in patients with osteoporosis, Paget's disease, and hyperthyroidism. Hydroxyproline levels were increased in patients with Paget's disease, and tartrate resistant acid phosphatase was increased in all the entities studied. Deoxypyridinoline can be a more sensitive marker than hydroxyproline, with some advantages, such as its quantitation in a urine specimen and its high bone specificity. In patients with renal failure, tartrate resistant acid phosphatase was the only biochemical marker of bone resorption with increased levels.  相似文献   

5.
Data from the measurement of broadband ultrasonic attenuation (BUA) and speed of sound (SOS), using the Lunar Achilles ultrasonic densitometer, were collected for Caucasian women from five centres in the United Kingdom (Leeds, London, Nottingham, Lincoln and Sheffield). After correcting for machine variability at each site, the data were combined into a central reference database comprising 2087 women aged 16-93 years. The data are presented in 5-year bands and show a mean fall of 0.36% per year for BUA and 0.08% per year for SOS in the 60 years following the attainment of peak bone mass. This fall in BUA compares with that observed using dual energy X-ray absorptiometry studies of the lumbar spine and femoral neck of 0.32% per year and 0.44% per year, respectively, for the age range 25-65 years.  相似文献   

6.
7.
Although direct evidence of carcinogenic risk from mammography is lacking, there is a hypothetical risk from screening because excess breast cancers have been demonstrated in women receiving doses of 0.25-20 Gy. These high-level exposures to the breast occurred from the 1930s to the 1950s due to atomic bomb radiation, multiple chest fluoroscopies, and radiation therapy treatments for benign disease. Using a risk estimate provided by the Biological Effects of Ionizing Radiation (BEIR) V Report of the National Academy of Sciences and a mean breast glandular dose of 4 mGy from a two-view per breast bilateral mammogram, one can estimate that annual mammography of 100,000 women for 10 consecutive years beginning at age 40 will result in at most eight breast cancer deaths during their lifetime. On the other hand, researchers have shown a 24% mortality reduction from biennial screening of women in this age group; this will result in a benefit-to-risk ratio of 48.5 lives saved per life lost and 121.3 years of life saved per year of life lost. An assumed mortality reduction of 36% from annual screening would result in 36.5 lives saved per life lost and 91.3 years of life saved per year of life lost. Thus, the theoretical radiation risk from screening mammography is extremely small compared with the established benefit from this life-saving procedure and should not unduly distract women under age 50 who are considering screening.  相似文献   

8.
A study on the determinants of bone mass in young women is being carried out among 287 young Chinese women aged 21-40 years. The baseline cross-sectional data show that the mean dietary calcium intake, estimated from the quantitative food frequency method, was 448 mg/day (standard deviation = 219). About 50% of the calcium source was from vegetables and 22% from dairy products. Among women aged 21-30 years, those with a dietary calcium intake of at least 600 mg/day had a 4%-7% higher mean bone mineral density at the spine and femur when compared with those with a mean intake below 300 mg/day. In women aged 31-40 years, subjects belonging to the highest quartile of calcium density (> or = 35 mg/420 kJ) had a 3%-8% higher mean bone mineral density at the spine and femur when compared with those in the lowest quartile (< 20.8 mg/420 kJ). Favorable calcium intake is beneficial in this population of young women with habitual low dietary calcium intake.  相似文献   

9.
Multivariate analysis was used to determine which characteristics: sex of the proband, sibling sex, severity of the proband's defect or family history, are the best predictors of recurrence risk among siblings of individuals with non-syndromic cleft lip with or without cleft palate (CL +/- P). Sibling recurrence risks are not significantly related to the sex of the proband. Severity of the proband's defect, classified by the extent of the lip defect (unilateral versus bilateral), was found to be a significant predictor of sibling recurrence, whereas involvement of the palate in the proband's defect was not. A positive family history of clefting (i.e. at least one affected first-degree relative in addition to the proband) and the sex of the sibling were also found to be significant predictors of sibling recurrence. The associations between sibling risk and family history, and sibling risk and bilaterality of the proband's defect appear to be mildly confounded. After adjusting for the effects of family history, the risk to siblings of probands with bilateral lip defects is twice the risk to siblings of probands with unilateral defects (O.R. = 2.00; 95% C.I. 1.25-3.19). A positive family history of clefting increases the risk to siblings by greater than 4-fold (O.R. = 4.49; 95% C.I. 2.74-7.35), after adjusting for the extent of the proband's lip defect. These results provide a rational strategy for identifying subsets of the 'at risk' population which have markedly different recurrence risks. This information is important for genetic counseling, since it allows for more precise estimation of sibling recurrence risks in individual cases.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
All men and women aged 40-42 years in Norway (except in Oslo, the capital city) were invited to tuberculosis and cardiovascular screenings during the period 1963-95. Height and weight were measured. Men who attended the last screening in 1991-95 were on average 3.0 cm taller than the generation who attended the first screening (1963-75). Women who were measured in 1991-95 were 2.7 cm taller. Mean weight increased 5.6 kg for men and 1.3 kg for women, while body mass index (BMI) increased 0.9 kg/m2 for men and decreased 0.3 kg/m2 for women. BMI has increased steadily in men, but in women a U-shaped time trend was found with a somewhat lower level for the last time period. The proportion with BMI above 30 kg/m2 has doubled among men and is now 9.1%, while in women the proportion has become slightly lower in the last period, and is now 8.4%. The mean BMI was highest in ex-smokers and lowest in current smokers, with persons who had never smoked in the middle. The difference between ex-smokers and current smokers was 0.9 kg/m2 in men and 0.7 kg/m2 in women.  相似文献   

11.
BACKGROUND: The effects of different therapies on bone loss rate can be measured using biochemical markers of bone resorption such as urinary hydroxyproline. AIM: To study the effects of hormone replacement therapy on urinary hydroxyproline in postmenopausal women. PATIENTS AND METHODS: Eighty three postmenopausal women without hormone replacement therapy, 54 postmenopausal women receiving hormone replacement therapy and 16 premenopausal women (considered as the control group) were studied. Hydroxyproline was measured in an early morning urine sample, after one day of diet without meat or gelatin. RESULTS: Urinary hydroxyproline in premenopausal women was 33.7 +/- 7.9 mg/g creatinine. The figure for postmenopausal women with hormonal replacement therapy was 33.7 +/- 5.9 mg/g creatinine. Postmenopausal women without replacement therapy had an urinary hydroxyproline of 47.4 +/- 8.5 mg/g creatinine, significantly higher than that of premenopausal and supplemented women. In 21 postmenopausal women, hydroxyproline was measured before and after three months of replacement therapy, values decreased 35.5 +/- 11% in this period and there was a direct correlation between initial values and the degree of reduction (r = 0.69, p < 0.001). CONCLUSIONS: Postmenopausal women receiving hormone replacement therapy have a urinary hydroxyproline excretion similar to that of premenopausal women.  相似文献   

12.
The quantification of biochemical markers of bone formation and resorption with kinetic measures of bone turnover is an essential step in their validation. Some biochemical markers have been validated by quantification against formation and resorption rates measured by calcium kinetics in adults with bone disease. However, none has been validated in healthy individuals who are undergoing skeletal growth and bone consolidation. Therefore, we have measured biochemical markers of bone formation (serum osteocalcin [OC], bone-specific alkaline phosphatase [BAP], and total alkaline phosphatase [ALP]) and resorption (serum tartrate resistant acid phosphatase [TRAP], urinary cross-linked N teleopeptides of type I collagen/creatinine [NTx/Cr], and hydroxyproline/creatinine [OHP/Cr]) in healthy females aged 11-32 years (n = 31) after an overnight fast to determine their relationship with bone formation (Vo+) and bone resorption (Vo-) as measured by calcium kinetics and balance. All biochemical markers were highly intercorrelated (r > 0.6, p < 0.001) as were Vo+ and Vo- (r = 0.91, p < 0.001). Highly significant correlations were present between bone formation measured by calcium kinetics (Vo+) and serum levels of bone biochemical markers (OC, r = 0.82, p = 0.001; ALP, r = 0.92, p = 0.001; and BAP, r = 0.90, p = 0.001) and between bone resorption measured by calcium kinetics (Vo-) and fasting serum levels and urine creatinine ratios of biochemical markers (TRAP, r = 0.77, p < 0.001; OHP/Cr, r = 0.79, p < 0.001; and NTx/Cr, r = 0.70, p < 0.001). Thus, biochemical markers of bone formation and resorption can be used to predict calcium kinetic rates during skeletal growth and the early years of formation of peak bone mass, ages at which strategies to build peak bone mass are important. Biochemical markers of formation and resorption are equally useful in predicting either the bone formation rate or the resorption rate.  相似文献   

13.
We studied the effects of high intensity resistance exercise training on bone metabolism in 17 young adult Oriental males (23-31 years) by measuring sensitive biomarkers of bone formation and resorption. The subjects were assigned to a training group and a sedentary group. The training group followed a weight training program three times per week for 4 months. In the training group, serum osteocalcin concentration and serum bone-specific alkaline phosphatase activity were significantly increased within the first month after the beginning of resistance exercise training, and the elevated levels remained throughout the training period, while there was no significant change in plasma procollagen type-I C-terminal concentration. Urinary deoxypyridinoline excretion was transiently suppressed and returned to the initial value but was never stimulated during the 4 months. These results suggest that the resistance exercise training enhanced bone formation without prior bone resorption. In the sedentary group, there was no significant difference in bone metabolic markers except plasma procollagen type-I C-terminal, which continuously decreased during the experimental period. There were no significant changes in total and regional bone mineral density in either group. In conclusion, (1) resistance exercise training increased markers of bone formation, while it transiently suppressed a marker of bone resorption, and (2) such adaptive changes of bone metabolism to resistance exercise training occurred during the early period of the training, before changes in bone density were observable through densitometry.  相似文献   

14.
Although 40% of US women indicate they are currently trying to lose weight, the association between intentional weight loss and longevity is unknown. The authors analyzed prospective data from 43,457 overweight, never-smoking US white women aged 40-64 years who in 1959-1960 completed a questionnaire that included questions on weight change direction, amount, time interval, and intentionality. Vital status was determined in 1972. Proportional hazards regression was used to estimate mortality rate ratios for women who intentionally lost weight compared with women who had no change in weight. Women who died within the first 3 years of follow-up were excluded. Analyses were stratified by preexisting illness and adjusted for age, beginning body mass index, alcohol intake, education, physical activity, and health conditions. In women with obesity-related health conditions (n = 15,069), intentional weight loss of any amount was associated with a 20% reduction in all-cause mortality, primarily due to a 40-50% reduction in mortality from obesity-related cancers; diabetes-associated mortality was also reduced by 30-40% in those who intentionally lost weight. In women with no preexisting illness (n = 28,388), intentional weight loss of > or = 20 lb (> or = 9.1 kg) that occurred within the previous year was associated with about a 25% reduction in all-cause, cardiovascular, and cancer mortality; however, loss of < 20 lb (< 9.1 kg) or loss that occurred over an interval of > or = 1 year was generally associated with small to modest increases in mortality. The association between intentional weight loss and longevity in middle-aged overweight women appears to depend on their health status. Intentional weight loss among women with obesity-related conditions is generally associated with decreased premature mortality, whereas among women with no preexisting illness, the association is equivocal.  相似文献   

15.
Previous studies have shown that treatment with estrogen or calcium decreases bone turnover in older women. The mechanisms by which estrogen and calcium exert their effects are probably different. We therefore examined the possibility of an additive or synergistic effect of combined treatment with calcium and low dose estrogen on bone turnover in older women, using biochemical markers. Thirty-one healthy women over 70 yr of age were randomized to 12 weeks of treatment with either micronized 17beta-estradiol [0.5 mg/day Estrace (E2)] or 1500 mg/day elemental calcium, given as carbonate plus vitamin D (800 IU/day; Ca+D). At the end of the initial 12-week treatment period, both groups received both Ca+D and E2 for an additional 12 weeks. Eleven older women were followed for 36 weeks without any treatment and served as a control group. Serum and urine were collected at baseline, at 12 and 24 weeks on treatment, and at 12 weeks after treatment was terminated for measurement of biochemical markers of bone turnover. Markers of bone formation were bone alkaline phosphatase, osteocalcin, and type I procollagen peptide; markers of bone resorption were urinary cross-linked C-telopeptides and N-telopeptides of type I collagen, serum cross-linked N-telopeptides of type I collagen, urinary free deoxypyridinoline cross-links, and serum bone sialoprotein. Repeated measures ANOVA was used to determine changes in bone turnover measures over time by group. All markers of bone resorption decreased with initial treatment and decreased further with combination therapy (P < 0.001). Markers of bone formation decreased with Ca+D treatment, but not with E2 alone; there was no additional effect of combination therapy on formation markers compared to Ca+D alone. Neither markers of formation nor resorption changed in the control group. These results suggest that there is an additive effect of low dose estrogen and calcium on bone resorption, but not on bone formation, in older women. Thus, the combination of low dose estrogen plus calcium is likely to be more effective in older women than either treatment alone.  相似文献   

16.
The effect of 2 months of treatment with the oral growth hormone (GH) secretagogue MK-677 on markers of bone metabolism was determined in healthy obese male subjects. This was a randomized, double-blind, parallel, placebo-controlled study. Twenty-four healthy obese males, 19-49 years of age, with body mass index > 30 kg/m2 were treated with MK-677 (25 mg/day; n = 12) or placebo (n = 12) for 8 weeks. MK-677 increased markers of bone formation; a 23% increase in the carboxy-terminal propeptide of type I procollagen levels and a 28% increase in procollagen III peptide levels were seen with as little as 2 weeks of MK-677 treatment (p < 0.01 and p = 0.001 vs. placebo, respectively) while a 15% increase in serum levels of osteocalcin was not detected until 8 weeks of treatment (p < 0.01 vs. placebo). Markers of bone resorption were induced within 2 weeks of treatment with MK-677; serum levels of the carboxy-terminal cross-linked telopeptide of type I collagen were increased 26% at 8 weeks (p = 0.001 vs. placebo), and urine hydroxyproline/creatinine and calcium/creatinine ratios at 8 weeks were increased by 23% (p < 0.05 vs. placebo) and 46% (p < 0.05 vs placebo), respectively, MK-677 increased serum insulin-like growth factor binding protein-5 (IGFBP-5) by 43-44% after 2-8 weeks of treatment (p < 0.01 vs. placebo). Serum IGFBP-4 was increased by 25% after 2 weeks of treatment (p < 0.001 vs. placebo) but no significant change from baseline was observed after 8 weeks of treatment. Plasma interleukin-6 was not significantly changed by active treatment. In conclusion, short-term treatment of healthy obese male volunteers with the GH secretagogue MK-677 increases markers of both bone resorption and formation. Large increases in serum levels of IGF-1 and IGFBP-5 and a transient increase in serum IGFBP-4 were found. Future long-term studies are needed to investigate if prolonged treatment with MK-677 increases bone mass.  相似文献   

17.
BACKGROUND: Alendronate sodium (Fosamax, Merck, Sharp & Dohme, Whitehouse Station, NJ, USA) is an aminobisphosphonate that can inhibit osteoclast-mediated bone resorption activity to reduce bone turnover rate and improve progressive gains in bone mass. METHODS: This was a randomized, double-blind, placebo-controlled study comparing the effects on bone turnover markers between daily treatment with alendronate sodium 10 mg and placebo. Forty early postmenopausal women completed three months of treatment. The bone turnover rate was determined by measuring the biochemical markers at baseline, week 6 and at the end of the three-month treatment period. All adverse events were recorded during each follow-up visit. RESULTS: Patients receiving alendronate treatment had a significant decrease in urinary excretion of the bone resorption marker deoxypyridinoline (Dpd) as well as one of the bone formation markers, bone-specific alkaline phosphatase (AlkP-B). Patients receiving placebo tended to have increased urinary excretion of bone resorption and formation markers. At the end of three months, the mean percentage change of Dpd and AlkP-B from baseline in the group receiving 10 mg alendronate was 30.49% and 29.45% reduction, respectively. The placebo group had 2.39% and 1.52% increase, respectively. Overall, three biochemical markers (Dpd, AlkP-B and osteocalcin) differed significantly between the treatment and control groups after three months of treatment. The drug was well tolerated, without a significant increase in incidence of adverse effects such as gastrointestinal discomfort and esophageal irritation. CONCLUSIONS: Bone turnover rate decreased quickly following drug administration. The incidence of adverse effects did not differ significantly between the alendronate and placebo groups. Alendronate is, therefore, recommended as an effective nonhormonal treatment for postmenopausal osteoporosis.  相似文献   

18.
PROBLEM: To determine whether cultured human decidual cells and chorion cells produce interleukin-10 (IL-10) after incubation with purified bacterial products. METHOD OF STUDY: Decidual cell cultures and chorion cell cultures were established by standard techniques. With confluence, monolayers of each culture were incubated with purified bacterial products, including various concentrations of lipopolysaccharide (LPS), lipid A, and lipoteichoic acid (LTA) for 16 hr in quadruplicate. Culture supernatants were collected and assayed for immunodetectable IL-10 by enzyme-linked immunoadsorbent assay (ELISA). RESULTS: Both decidual cell cultures and chorion cell cultures produced significant quantities of IL-10 after stimulation with LPS, lipid A, and LTA. Cultures of decidual cells produced more IL-10 than did chorion cell cultures. CONCLUSIONS: Our data indicate that both maternal decidual cells and fetally derived chorion cells can produce IL-10 after incubation with bacterial virulence factors. This finding contrasts with our previous findings in which chorion cells did not produce IL-10 after stimulation with IL-1 beta, suggesting that chorion cell production after incubation with bacterial products is independent of IL-1 beta. We speculate that the contribution of anti-inflammatory IL-10 production by human gestational tissues to the inflammatory process in these tissues may be overcome or abrogated by the pro-inflammatory process.  相似文献   

19.
The induction of the his(-)-->his+ mutants in vegetative and spores of Bacillus subtilis wild-type cells irradiated with gamma rays and helium ions (LET = 20-80 keV/micron) has been investigated. It was shown that the dose dependence of the mutation induction in vegetative cells is described by a linear-quadratic function of dose in case of both gamma-rays and helium ions. RBE (LET) dependencies on the lethal and mutagenic effect of irradiation have a local maximum. The maximum of RBE (LET) dependence on the mutagenic assay is shifted at the low region of LET in comparison with the lethal effect of irradiation.  相似文献   

20.
Increased bone turnover has been suggested as a potential risk factor for osteoporotic fractures. We investigated this hypothesis in a prospective cohort study performed on 7598 healthy women more than 75 years of age. One hundred and twenty-six women (mean years 82.5) who sustained a hip fracture during a mean 22-month follow-up were age-matched with three controls who did not fracture. Baseline samples were collected prior to fracture for the measurement of two markers of bone formation and three urinary markers of bone resorption: type I collagen cross-linked N- (NTX) or C-telopeptide (CTX) and free deoxypyridinoline (free D-Pyr). Elderly women had increased bone formation and resorption compared with healthy premenopausal women. Urinary excretion of CTX and free D-Pyr, but not other markers, was higher in patients with hip fracture than in age-matched controls (p = 0.02 and 0.005, respectively). CTX and free D-Pyr excretion above the upper limit of the premenopausal range was associated with an increased hip fracture risk with an odds ratio (95% confidence interval) of 2.2 (1.3-3.6) and 1.9 (1.1-3.2), respectively, while markers of formation were not. Increased bone resorption predicted hip fracture independently of bone mass, i.e., after adjustment for femoral neck bone mineral density (BMD) and independently of mobility status assessed by the gait speed. Women with both a femoral BMD value of 2.5 SD or more below the mean of young adults and either high CTX or high free D-Pyr levels were at greater risk of hip fracture, with an odds ratio of 4.8 and 4.1, respectively, than those with only low BMD or high bone resorption. Elderly women are characterized by increased bone turnover, and some markers of bone resorption predict the subsequent risk of hip fracture independently of hip BMD. Combining the measurement of BMD and bone resorption may be useful to improve the assessment of the risk of hip fracture in elderly women.  相似文献   

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