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101.
Low birth weight increases the risk of developing adult onset cardiovascular and metabolic diseases. Recently being born small has also been identified as a risk factor for adverse bone growth, development and adult fracture risk. Evidence also suggests that accelerated growth in offspring of normal birth weight, following periods of slowed growth, can also independently program adult diseases. The aim of this study was to determine the relative roles of prenatal and postnatal growth restriction on adult bone characteristics and strength. Bilateral uterine vessel ligation (Restricted) or sham surgery (Control) was performed on gestational day 18 in WKY rats to induce fetal growth restriction. Control, Reduced (reduced Control litter size to match Restricted) and Restricted pups were cross-fostered onto different Control (normal lactation) or Restricted (impaired lactation) mothers 1 day after birth. Femur length, dimensions, strength, mineral content and density were quantified using DXA and pQCT analysis. Markers of bone turnover were measured in offspring at 6 months. Restricted pups were born lighter than Controls with males, not females, remaining smaller than Control-on-Control at 6 months (P < 0.05). Pups born of normal weight from a reduced litter suckling on a Restricted mother (Reduced-on-Restricted) grew slowly during lactation then quicker after weaning compared to Controls (P < 0.05). Cortical bone mineral content, dimensions and strength were lower in Restricted-on-Restricted and Reduced-on-Restricted offspring compared to Controls with lower density in Reduced-on-Restricted females (P < 0.05). The stress strain index of bone bending strength remained lower in the Restricted male offspring when body weight adjustments were made. Cross-fostering Restricted females, but not males, onto mothers with normal lactation (Restricted-on-Control) restored growth and bone parameters to Controls (P < 0.05). Being born small, or postnatal growth restriction for normal birth weight offspring followed by accelerated growth, programs bone content and strength deficits. Deficits were corrected by improving postnatal nutrition for females born small, highlighting sex specific programming outcomes and impact of postnatal nutrition. These findings suggest a link between growth restriction and adult bone health with additional studies needed to further explore this link in humans.  相似文献   
102.
K-ras mutation-positive (K-ras+) and -negative (K-ras-) colorectal adenomas may differ clinically and pathologically. As environmental compounds may cause mutations in the growth-related K-ras oncogene or affect clonal selection depending on mutational status, we evaluated whether the aetiology of K-ras+ and K-ras- adenomas differs. K-ras mutations in codons 12 and 13 were assessed in colorectal adenoma tissue (K-ras+: n = 81, K-ras-: n = 453). Dietary and lifestyle data were collected through questionnaires that were also administered to 709 polyp-free controls. Multiple logistic regression analyses showed that intake of vitamin B2 and monounsaturated fat were differently associated with risk of K-ras+ and K-ras- adenomas; vitamin B2 was inversely associated with K-ras- (highest vs. lowest tertile: odds ratio (OR) = 0.70, 95% confidence interval (CI) = 0.50-0.97, p trend = 0.020), but not with K-ras+ adenomas, and a positive association with monounsaturated fat was confined to K-ras- adenomas (OR = 1.57, 95% CI = 1.06-2.34, p trend = 0.029). Besides, potential, not statistically significant, differences in risk arose because red meat was distinctly positively associated with K-ras+ adenomas (OR = 1.70, 95% CI = 0.94-3.09, p trend = 0.061); total dietary and polyunsaturated fat tended to be inversely associated with risk of K-ras+ but not of K-ras- adenomas; inverse associations with dairy products, calcium, protein and tea were confined to K-ras- adenomas, and smoking was more markedly positively associated with K-ras- adenomas. No differences in risk of K-ras+ and K-ras- adenomas could be detected for other factors. In conclusion, dietary and lifestyle factors may influence risk of K-ras+ and K-ras- adenomas differently. However, epidemiological literature on diet, lifestyle and colorectal K-ras mutations is inconsistent.  相似文献   
103.
OBJECTIVE: The aim of this study was to assess the relative strength of the association of endogenous estradiol and androgens with bone loss at the lumbar spine and femoral neck during the menopausal transition. DESIGN: A longitudinal study of a population-based cohort of 159 Australian-born women who at baseline had a mean age of 50.0 years (SD=2.4) and had menstruated in the prior 3 months. BMD was measured by dual-energy X-ray absorptiometry at the lumbar spine and femoral neck on up to three occasions. RESULTS: Of the 159 participants, 50 had two BMD measurements and 109 had a third measure. The mean time between the first and final measures for the whole group was 39 months and at the time of the final measures 49% of the participants had become postmenopausal. The mean percentage change/year in lumbar spine BMD was -0.9% (95% CI, -1.1 to -0.6) and at the femoral neck, -0.5% (95% CI, -0.7 to -0.2). A highly significant association with estradiol at the final time point was found, whereas the contribution of estradiol at baseline was negligible. The variance explained by estradiol levels was 19% and 11% for change in BMD at the LS and FN, respectively. Excluding baseline estradiol values and using the average of change in BMD at the LS and FN, the final regression equation estimated that an estradiol level of 330 pmol/l (95% CI, 274 to 386) and 245 pmol/l (95% CI, 194 to 296) is required for preservation of LS and FN BMD, respectively. A stepwise linear regression model was used to assess the effect of age, BMI, estradiol, testosterone, DHEAS, SHBG, and free testosterone index on changes in BMD and found that only the final estradiol level had a significant association with change in BMD. CONCLUSION: Endogenous estradiol was the only hormone among those investigated to have a significant effect on bone mineral density during the menopausal transition.  相似文献   
104.
Patellar tendinopathy is often treated surgically after failure of conservative treatment but clinical experience suggests that results are not uniformly excellent. The aim of this review was to (i) identify the different surgical techniques that have been reported and compare their success rates, and (ii) critically assess the methodology of studies that have reported surgical outcomes. Twenty-three papers and two abstracts were included in the review. Surgical procedures were categorized and outcomes summarized. Using ten criteria, an overall methodology score was derived for each paper. Criteria for which scores were generally low (indicating methodological deficiency) concerned the type of study, subject selection process and outcome measures. We found a negative correlation between papers' reported success rates and overall methodology scores ( r =−0.57, P <0.01). There was a positive correlation between year of publication and overall methodology score ( r =0.68, P <0.001). We conclude that study methodology may influence reported surgical outcome. We suggest practical guidelines for improving study design in this area of clinical research, as improved study design would provide clinicians with a more rigorous evidence-base for treating patients who have recalcitrant patellar tendinopathy.  相似文献   
105.
Although hypnosis has been used for centuries, there are few reports of systematic, professional training. The most thorough codification of instructional content is the Standards of Training in Clinical Hypnosis (SOTCH) (Elkins & Hammond, 1994), endorsed by The American Society of Clinical Hypnosis (ASCH), and The Society of Clinical and Experimental Hypnosis (SCEH) for annual workshops. This curriculum is organized around two assumptions: training is presented to adult professional who know their own objectives; and each participant has a favorite learning style that should be accommodated. The workshop follows the content and time recommendations of the SOTCH. Some content is scheduled with spaced opportunity for practice. Concepts are organized in a spiral pattern, then presented and reviewed several times, each time in more detail, and in ways that accommodate different learning styles.  相似文献   
106.
Background: The aetiology of osteoporotic vertebral fracture is multifactorial and may be conceptualised using a systems framework. Previous studies have established several correlates of vertebral fracture including reduced vertebral cross-sectional area, weakness in back extensor muscles, reduced bone mineral density, increasing age, worsening kyphosis and recent vertebral fracture. Alterations in these physical characteristics may influence biomechanical loads and neuromuscular control of the trunk and contribute to changes in subregional bone mineral density of the vertebral bodies. Methods: This review discusses factors that have received less attention in the literature, which may contribute to the development of vertebral fracture. A literature review was conducted using electronic databases including Medline, Cinahl and ISI Web of Science to examine the potential contribution of trabecular architecture, subregional bone mineral density, vertebral geometry, muscle force, muscle strength, neuromuscular control and intervertebral disc integrity to the aetiology of osteoporotic vertebral fracture. Interpretation: A better understanding of factors such as biomechanical loading and neuromuscular control of the trunk may help to explain the high incidence of subsequent vertebral fracture after sustaining an initial vertebral fracture. Consideration of these issues may be important in the development of prevention and management strategies.  相似文献   
107.
MicroRNAs are endogenous, regulatory RNAs implicated in many biological processes including pigmentation. Software algorithms and in vitro experiments predict that microRNAs can target pigmentation pathway genes, but few have been tested in vivo. MiR‐128‐1, a microRNA within the strongly selected lactase locus in the human genome, has predicted pigmentation targets. To test the role of miR‐128‐1 in pigment regulation, we created C57BL/6 agouti miR‐128‐1 knockout mice and quantified melanin deposition in hair. MiR‐128‐1 knockout mice have no detectable hair pigmentation phenotype. We conclude that miR‐128‐1 does not play a significant regulatory role in hair pigmentation in mice.  相似文献   
108.
The age and developmental stage at which calcium supplementation produces the greatest bone effects remain controversial. We tested the hypothesis that calcium supplementation may improve bone accrual in premenarcheal females. Fifty-one pairs of premenarcheal female twins (27 monozygotic and 24 dizygotic; mean +/- sd age, 10.3 +/- 1.5 yr) participated in a randomized, single-blind, placebo-controlled trial with one twin of each pair receiving a 1200-mg calcium carbonate (Caltrate) supplement. Areal bone mineral density (aBMD) was measured at baseline and 6, 12, 18 and 24 months. There were no within-pair differences in height, weight, or calcium intake at baseline. Calcium supplementation was associated (P < 0.05) with increased aBMD compared with placebo, adjusted for age, height, and weight at the following time points from baseline: total hip, 6 months (1.9%), 12 months (1.6%), and 18 months (2.4%); lumbar spine, 12 months (1.0%); femoral neck, 6 months (1.9%). Adjusted total body bone mineral content was higher in the calcium group at 6 months (2.0%), 12 months (2.5%), 18 months (4.6%), and 24 months (3.7%), respectively (all P < 0.001). Calcium supplementation was effective in increasing aBMD at regional sites over the first 12-18 months, but these gains were not maintained to 24 months.  相似文献   
109.
Residents from high level (nursing homes) and low-level care facilities (hostel) being served the three common diet texture modifications (full diet, soft-minced diet and pureed diet) were assessed. Individual plate waste was estimated at three meals on one day. Fifty-six males and 156 females, mean age 82.9+/-9.5 (SD) years, of which 139 lived in nursing homes (NH) and 76 in hostels (H) were included. Mean total energy served from meals was 5.3 MJ/day, 5.1 to 5.6 MJ/day, 95% confidence intervals (CI), in NH which was less than in H, 5.9 MJ/day (CI 5.6 to 6.2 MJ/day) (P=0.007). Protein and calcium intakes were lower in NH, 44.5g (CI 41.5 to 47.5g), 359.0mg (CI 333.2 to 384.8mg), versus 50.5g (CI 46.6 to 54.3g), 480.5mg (CI 444.3 to 516.7mg) in H (P=0.017, P<0.001 respectively). There was no difference in nutrient/energy ratios, except for protein/energy, which was higher in NH 11.7 (CI 11.3 to 12.2) than in H 9.8 (CI 9.4 to 10.3) (P<0.001). Ability to self-feed had no significant effect on nutrient intakes in NH. The self fed group (N=63) had the following nutrient intakes: energy 4.0 MJ (CI 3.6 to 4.3 MJ), protein 44.6g (CI 40.3 to 48.9g), calcium 356.9mg (CI 316.3 to 397.4mg), fibre 14.9g (CI 13.2 to 16.5g). The assisted group (N=64) had the following nutrient intakes: energy 3.9MJ (CI 3.6 to 4.2MJ), protein 46.0g (CI 40.7 to 49.6), calcium 361.9mg (CI 327.8 to 396.1mg), fibre 14.9g (CI 13.2 to 16.1g). Of NH classified as eating impaired, 36% received no assistance with feeding and had lower intakes of protein 37.8g (CI 33.0 to 42.1g) compared to those receiving some assistance 46.1g (CI 41.3 to 50.9g) (P=0.026). Reduced energy intake accounted for the differences in nutrient intakes between nursing homes and hostels, except for protein. Strategies to effectively monitor nutrient intakes and to identify those with eating impairment are required in order to ensure adequate nutrition of residents in nursing homes and hostels.  相似文献   
110.
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