No description available.

No description available.

Weakness and subjective fatigue are common features of rheumatoid arthritis (RA). However, whether there is a true increase in the fatigability of rheumatoid skeletal muscle, in which fibre atrophy has been frequently reported, is unclear. Such factors may influence the ability to respond to exercise programmes. In this work, a reliable and sensitive technique for the objective measurement of forearm muscle fatigue during sustained grip was developed, using power spectral analysis of the surface myoelectric signal (SMES).The inter-relationships between grip force (hand function) and the activity and severity of the rheumatoid disease process with muscle fatigue (defined as the decline in the median frequency of the SMES with work, (MDFG)) and the initial median frequency of the SMES (IMF) were examined. It has been previously suggested that the IMF of the SMES may reflect the fibre type of the underlying muscle. The response to a 12-week progressive right hand grip strengthening programme in healthy females and those with RA was also evaluated. Potential predictors of outcome and the mechanisms of strength gain were examined. Forearm muscle fatigue in RA was not significantly greater than in healthy controls. However, higher levels of fatigue were associated with greater systemic disease activity and greater disease severity. The IMF of the SMES was shown to be stable over a wide range of grip forces for a given individual. It was significantly elevated in rheumatoid subjects, and showed a direct association with greater disease severity. Handgrip exercise was highly effective in improving hand function in females with RA. Strength gains were also demonstrated in healthy controls. Subjects with more severe disease and greater IMF of the SMES showed the greatest improvement in hand function. Greater systemic and local disease activity during the 12-week programme were limiting factors to improvement in grip. Local (right hand) disease activity remained stable or improved in the RA group overall, in spite of a trend towards deteriorating systemic and left handed disease activity. The two main potential mechanisms of strength gain (neural adaptation and gains in muscle mass) were assessed in both rheumatoid and healthy groups. The former was assessed by evaluation of the neuromuscular efficiency, derived from the relationship of the root mean square of the SMES at a given grip force. Gains in muscle mass were also assessed using this technique and by volumetric analysis of forearm musculature using magnetic resonance imaging. Although significant gains in muscle mass were demonstrated in the control group, no such gains were seen in the rheumatoid subjects. This indicates that neural adaptation was an effective method of strength gain in the rheumatoid group.

PhD, Faculty of Health Sciences, University of the Witwatersrand / Many studies have shown a negative effect of depot-medroxyprogesterone acetate (DMPA) hormonal contraception on bone mineral density (BMD) in women. There is limited information on the effect of norethisterone enanthate (NET-EN) on BMD and the effect of combined oral contraceptives (COCs) on BMD is inconclusive, however emerging evidence is showing that low-dose COCs maybe detrimental to BMD in young women. The aim of this research was to evaluate, in a 5-year follow-up study, the possible effect of DMPA, NET-EN and COCs on BMD among young (15-19 years) and older (40-49 years) South African women. Method: This prospective study was conducted at the Commercial City Family Planning clinic in Durban, South Africa between 2000 and 2007. In the adolescent group women with no history of hormonal contraception who were initiating use of DMPA (n=115), NET-EN (n=115) or COCs (n=116) and 144 nonuser controls were recruited. In the older group, one hundred and twenty seven users of DMPA, 102 NET-EN users and 106 COC users of at least one year were compared to 161 nonuser controls. BMD was measured at the distal radius and midshaft of the ulna using dual x-ray absorptiometry. In the crosssectional component of the study conducted at the end of the longitudinal phase, BMD was measured at the hip, spine and femoral neck in a sub-group of 96 of the younger women. Results: In the longitudinal study of adolescents, BMD increased in all four groups during follow-up (p<.001). There was evidence for lower BMD increases per annum in NET-EN (p=.050) and COC (p=.010) users compared to nonusers but no difference between DMPA and nonusers (p=.76). In 14 NET-EN discontinuers, an overall reduction of 0.61% per year BMD was followed, upon cessation, by an increase of 0.69% per year (p=.066). The cross-sectional sub-study found that young women in the injectables-only user group had lower BMDs compared to the non-user group after adjusting for BMI at the spine (p=0.042), hip (p=0.025), and femoral neck (p=0.023). The mixed COC/injectable user group BMD values were lower than controls; however, they were not significant at any of the three sites. In the older women, there was no significant difference in radius BMD between the contraceptive user groups and the non-user controls (p=.26) with and without adjustment for age at baseline, or after two and a half years of follow-up (p=0.52). Conclusion: This study suggests that BMD increases in adolescents may be less in NETEN and COC users; however, recovery of BMD in NET-EN users was found in the small sample of adolescents followed post-discontinuation. The cross-sectional sub-study showed similar findings in long-term injectable users, but not when women had mixed injectable and COC use. There was no evidence that long-term use of DMPA, NET-EN and COCs affected BMD in the older women.

Diss. (sammanfattning) Uppsala : Univ., 2001. / Härtill 4 uppsatser.

No description available.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 5 uppsatser.

Mahmood Ahmed. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1991. / Includes bibliographical references. / Title / Contents --- p.i-iii / Abstract --- p.2 / Introduction --- p.5 / Definitions : --- p.7 / Chapter - --- Bone --- p.7 / Chapter - --- Bone Cells --- p.9 / Chapter - --- Types of Bone & the Mineral Contents --- p.10 / Chapter - --- Composition of Bone Mass --- p.11 / Chapter - --- Bone Mass --- p.11 / Chapter - --- Factors Affecting The Bone Mass --- p.12 / Bone Minerals --- p.13 / Non Invasive Methods of Measurement of BMC : --- p.16 / Chapter - --- Radiograph --- p.16 / Chapter - --- Quantitative Morphometric --- p.16 / Chapter - --- Radiographic Photodensitometry --- p.16 / Chapter - --- Neutron Activation --- p.17 / Chapter - --- Quantitative Computed Tomography --- p.17 / Chapter - --- Bone Absorptiometery --- p.18 / Chapter - --- Transmission of Ultrasonics --- p.18 / Chapter - --- Dual Photon Absorptiometry --- p.19 / Chapter - --- Bone Scan --- p.19 / Chapter - --- Bone - Specific Biochemical Markers --- p.20 / Chapter - --- Summary --- p.20 / Effects of Drugs on Bone Mass: --- p.22 / Chapter - --- Alcohol --- p.22 / Chapter - --- Tetracycline --- p.22 / Chapter - --- Corticosteroid --- p.23 / Chapter - --- Antacids --- p.23 / Chapter - --- Estrogen --- p.24 / Chapter - --- Vitamins --- p.24 / Causes of Osteopenia in Children --- p.25 / Physical Activity and BMC --- p.28 / Bone Mineral Content - Reviews : --- p.30 / Chapter - --- In Neonates --- p.30 / Chapter - --- Normative Surveys in Children --- p.32 / Chapter - --- Skeletal Abnormalities --- p.35 / HK Chinese Children: / Chapter - --- A General View --- p.37 / Objectives of Study --- p.40 / Chapter - --- Determination of Normal Range --- p.40 / Chapter - --- Determination of Peak Bone Mass --- p.41 / Measurement of BMC : --- p.43 / Chapter - --- Material --- p.43 / Methods and Subjects --- p.46 / Chapter - --- Location of Scanning Site --- p.46 / Chapter - --- Recruitment of Subjects --- p.47 / Chapter - --- Statistical Analysis --- p.48 / Reproducibility of Measurement: --- p.56 / Chapter - --- The Means --- p.56 / Chapter - --- The Correlations --- p.57 / Results --- p.58 / Chapter - --- 6 months to 3 years --- p.58 / Chapter - --- 3 to 7 years --- p.60 / Chapter - --- 7 to 18 years --- p.61 / Chapter - --- 3 to 18 years --- p.62 / Chapter - --- Dual Energy X-Ray Absorptiometry versus Single Photon Absorptiometry --- p.66 / Graphs & Charts / Chapter - --- Age Distribution --- p.50 / Chapter - --- Dominance Distribution --- p.51 / Chapter - --- BMC from 0.6 to 2.9 years --- p.59 / Chapter - --- BMC Male & Female Difference --- p.63 / Chapter - --- BMC Dominance Difference --- p.64 / Chapter - --- BMC Predicted & Measured Value --- p.65 / Chapter - --- BMD by SPA vs DEXA --- p.67 / Discussions --- p.68 / Chapter - --- BMC & Total Body Calcium --- p.68 / Chapter - --- Age --- p.70 / Chapter - --- Handedness --- p.71 / Chapter - --- Bone Width --- p.72 / Chapter - --- Weight --- p.73 / Chapter - --- Sex --- p.73 / Chapter - --- Height --- p.74 / Chapter - --- "Nutritional Status, Calc. Intak" --- p.74 / Comparison --- p.75 / Chapter - --- BMC in Pathological Conditions --- p.75 / Chapter - --- Comparison with other series --- p.76 / Conclusion --- p.82 / Diagram --- p.45 / Chapter - --- Schematic Diagram of Equipment --- p.45 / Picture --- p.52 / Chapter - --- Single Photon Absorptiometry --- p.52 / Chapter - --- Dual Energy X-Ray Absorptiometry --- p.53 / Chapter - --- Single Photon Absorptiometry (Neonates) --- p.54 / Chapter - --- Photon Absorption Technique --- p.55 / Table --- p.78 / Chapter - --- Table I (Average yearly BMC & BMD) --- p.78 / Chapter - --- Table II(Average yearly Change in BMC) --- p.79 / Chapter - --- TableIII(BMC from 3 to 18 years) --- p.80 / Chapter - --- Table IV (Regression Analysis) --- p.81 / Appendix --- p.83 / Acknowledgements --- p.95 / References --- p.96-99

Thesis (M.S.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / Adults with Intellectual Disability (ID) are at an elevated risk of osteoporosis based on lower peak bone mass and medical characteristics. However, there is little data as to how the medical characteristics affect screening or at what ages people are being screened. Methods: A secondary cross-sectional data analysis of was conducted of 4777 adults witl1 Intellectual Disability to determine characteristics associated with an elevated risk for osteoporosis and receipt of bone density screening. Hypotheses were that increasing age, use of antiseizure medication, living in a 24 hour residential setting, and receiving a flu vaccine increased the likelihood of screening. Bivariate analyses were initially performed, tl1en data were stratified by gender and logistic regressions were performed. Findings: 22.2% of the sample in this study received bone density screening. Bivariate odds ratios identified each of the hypothesized variables as significantly associated with receiving screening. Additionally, many of the covariates analyzed identified significant associations with receiving screening.Data were then stratified by gender and evaluated in a logistic regression. In men, increasing age, tl1e use of antiepileptic medication (adjusted odds ratio (OR) 1.5; 95% confidence interval (CI) 1.2-2.0), and receiving the flu vaccine (adjusted OR 1.5; 95% CI 1.2-2.0) were associated witl1 an increased likelihood of screening, controlling for confounding. Living in a 24 hour residential setting was not significantly associated with screening (adjusted OR 1.2; 95% CI 0.91-1.6). In women, increasing age, the use of antiepileptic medication (adjusted OR 1.5; 95% CI 1.2-1.9), receiving the flu vaccine (adjusted OR 1.4; 95% CI 1.1-1.8), and living in a 24 hour residential setting (adjusted OR 1.4; 95% CI 1.1 -1.8) were all significantly associated with receiving screening. A history of Down syndrome, noted to increase risk of osteoporosis, was associated with a decreased likehl1ood of screening (adjusted OR 0.67; 95% CI 0.4 7-0. 94) in women, although it was not a significant association in men. Conclusions: While most variables related to osteoporosis are associated with an increased likelihood of screening, screening rates among in adults witl1 ID were low. Additionally, men and women have differences in variables related to screening. Better education and improved awareness may increase rates. / 2031-01-02

No description available.