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Karen Charlton Marijka Batterham Kelly Langford Jenna Lateo Erin Brock Karen Walton Philippa Lyons-Wall Katie Eisenhauer Nick Green Cameron McLean 《Nutrients》2015,7(9):7126-7142
Impaired strength adversely influences an older person’s ability to perform activities of daily living. A cross-sectional study of 117 independently living men and women (age = 73.4 ± 9.4 year; body mass index (BMI) = 27.6 ± 4.8 kg/m2) aimed to assess the association between body composition and: (1) upper body strength (handgrip strength, HGS); (2) lower extremity performance (timed up and go (TUG) and sit to stand test (STS)); and (3) endurance (6-minute walk (SMWT). Body composition (% fat; lean body mass (LBM)) was assessed using bioelectrical impedance. Habitual physical activity was measured using the Minnesota Leisure Time Physical Activity Questionnaire (MLTPA) and dietary macronutrient intake, assessed using 24 h recalls and 3-day food records. Regression analyses included the covariates, protein intake (g/kg), MLTPA, age and sex. For natural logarithm (Ln) of right HGS, LBM (p < 0.001) and % body fat (p < 0.005) were significant (r2 = 46.5%; p < 0.000). For left LnHGS, LBM (p < 0.000), age (p = 0.036), protein intake (p = 0.015) and LnMLTPA (p = 0.015) were significant (r2 = 0.535; p < 0.000). For SMW, % body fat, age and LnMLTPA were significant (r2 = 0.346; p < 0.000). For STS, % body fat and age were significant (r2 = 0.251; p < 0.000). LBM is a strong predictor of upper body strength while higher % body fat and lower physical activity are associated with poorer outcomes on tests of lower extremity performance. 相似文献
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Perry D Stewart N Benton N Robinson E Yeoman S Crabbe J McQueen F 《The Journal of rheumatology》2005,32(2):256-267
OBJECTIVE: To compare the detection and scoring of erosions in patients with rheumatoid arthritis (RA) using magnetic resonance (MR) and multidetector helical computerized tomographic (CT) scanning. METHODS: Comparative CT and MR scans of the dominant wrist were obtained from 9 patients with RA and clinical examination was performed to assess disease activity. MR and CT scans were scored for erosions and MR scans for bone edema by 2 radiologists using a validated system. Radiographs of the hands and feet were also scored for erosions using the modified Sharp score. RESULTS: In 117 of 135 (87%) sites there was concordance for erosions between MR and CT scans. At the remaining 18/135 sites (13%), erosions were identified by CT but not MR in 12/135 (9%) and by MR but not CT in 6/135 (4%). Partial volume artefacts on MR images and shifts in slice position were the most common reasons for erosion mismatch between MR and CT. The mean CT bone erosion score was significantly higher than the MR erosion score when individual bony sites were examined (p = 0.024), with the greatest difference being at the metacarpal bases. The total bone erosion score also tended to be higher on CT than MR [median scores of 20 (range 0-66) and 12 (0-51), respectively; p = 0.060]. MR and CT erosion scores correlated strongly with the total Sharp score (r = 0.93, p = 0.0002 and r = 0.94, p = 0.0002, respectively) and with the Disease Activity Score (MR: r = 0.77, p = 0.02; CT: r = 0.71, p = 0.03). CONCLUSION: Most erosions were detected using both modalities, but erosion scores were higher on CT than MR scans, especially at the metacarpal bases. It is possible that small erosions in some regions are more easily detected by CT because of its ability to clearly delineate cortical bony margins. 相似文献
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Ryan CE Elliott JH Middleton T Mijch AM Street AC Hellard M Crofts N Crowe SM Oelrichs RB 《AIDS research and human retroviruses》2004,20(12):1364-1367
The proportion of human immunodeficiency virus type 1 (HIV-1) among Vietnamese injecting drug users (IDUs) in Melbourne, Australia exceeds that of the background population. To investigate the molecular epidemiology of HIV-1 among this group, the C2-V4 region of the HIV-1 envelope was directly sequenced from 11 Vietnamese Australians and 19 non-Vietnamese Australian controls. A significant difference in the distribution of the HIV-1 subtypes was demonstrated, with greater than 50% of Vietnamese Australian IDU shown to be infected with CRF01_AE-the predominant subtype in Southeast Asia, rather than subtype B, which dominates the Australian epidemic and which was found in 89.5% of the non-Vietnamese controls. The genetic diversity of the CRF01_AE epidemic in Vietnamese Australian IDUs was substantially lower that that of the background subtype B, consistent with a more recent introduction of a limited number of viral strains from Vietnam. These results support public health policy targeting Australian IDUs of Vietnamese ethnicity as a distinct vulnerable population. 相似文献
76.
Bijsterveld NR Middeldorp S Berends F Büller HR 《Journal of thrombosis and thrombolysis》2000,9(3):263-269
Background: Lupus anticoagulant (antiphospholipid antibodies) is associated with venous and arterial thrombosis in patients with and without autoimmune disorders. Vitamin K antagonists are the treatment of choice in patients with thrombosis, of which the dose is titrated by INR monitoring. Several recent reports suggest that the presence of the lupus anticoagulant disturbs the INR test and may lead to unreliable results with a large variation in INR values, dependent on the reagents used.Methods: We studied 11 lupus anticoagulant positive patients and 11 lupus anticoagulant negative patients, all using vitamin K antagonists. The INR value was determined using seven different tests and the variation in INR values was compared between the two groups. The amidolytic Factor X levels were used as an phospholipid independent measure for intensity of warfarin therapy. Factor VII and X activity were measured to assess the stability of warfarin therapy.Results: The variation of the results with different INR tests within one patient was minimal and comparable in the two groups for INR's in the therapeutic range. The coefficient of variation for the cases and control group was 10.43 and 9.35, respectively. Variation in both groups increased at supratherapeutic levels of anticoagulation and when the anticoagulation was unstable (measured with Factor X/Factor VII ratio). The relationship between INR values and Factor X analysis revealed no influence of the lupus anticoagulant.Conclusions: In this study, lupus anticoagulant antibodies do not disturb INR laboratory tests. Differences in INR measurements are seen in patients with a high intensity of anticoagulation and in patients who either just started or in whom no stable anticoagulation has been achieved.Abbreviated Abstract. This study investigates the influence of lupus anticoagulant on INR determination tests in patients treated with warfarin. Eleven cases and eleven lupus anticoagulant negative control patients, also on warfarin therapy, were included. Seven INR results per patient were obtained using different laboratory tests. A factor X assay was performed to obtain an independent measure for the intensity of warfarin therapy.The variation of INR results between the cases and controls revealed no difference in these groups. In addition, the relationship between INR values and Factor X analysis indicated no influence of the lupus anticoagulant. What was observed was an increased difference in INR values in patients with a high intensity of anticoagulation and in patients who either just started or in whom no stable anticoagulation has been achieved 相似文献
77.
Matthew Richardson Nick Freemantle Melanie J Calvert John G F Cleland Luigi Tavazzi 《European heart journal》2007,28(15):1827-1834
AIMS: The cardiac resynchronization therapy in heart failure trial (CARE-HF) demonstrated that cardiac resynchronization therapy (CRT) reduces morbidity and mortality in patients with heart failure and cardiac dyssynchrony. The aim of this study was to develop a prognostic model to evaluate the relationship between prospectively defined patient characteristics and treatment on the trial primary outcome of death from any cause or unplanned hospitalization for a major cardiovascular event. METHODS AND RESULTS: A total of 813 patients were enrolled in the CARE-HF study and were followed for a mean of 29.4 months. A Cox Proportional Hazards Model was fitted to identify predictors of the primary outcome and any predictors that modified the effect of CRT. Ischaemic aetiology, more severe mitral regurgitation and increased N-terminal pro-brain natriuretic peptide, were associated with an increased risk of death or unplanned cardiovascular hospitalization irrespective of cardiac resynchronization [Hazard ratio (HR) 1.89, 95% CI 1.45-2.46, HR 1.71, 95% CI 1.38-2.12 and HR 1.31, 95% CI 1.17-1.47, respectively] and increasing systolic blood pressure with a decreasing risk of an event (HR 0.99, 95% CI 0.98-1.00). The benefits of cardiac resynchronization were modified by systolic blood pressure and interventricular mechanical delay (IVMD). Patients with increasing systolic blood pressure appear to receive reduced benefit from CRT (HR 1.02, 95% CI 1.00-1.03), whereas those patients with more severe IVMD appear to benefit more from treatment (HR 0.99, 95% CI 0.98-1.00). CONCLUSION: Patients with echocardiographic evidence of more severe cardiac dyssynchrony and low systolic blood pressure obtain greater benefit from CRT, although benefits were substantial across the range of subjects included in the trial. 相似文献
78.
Sean P. Saunders Christabelle S.M. Goh Sara J. Brown Colin N.A. Palmer Rebecca M. Porter Christian Cole Linda E. Campbell Marek Gierlinski Geoffrey J. Barton Georg Schneider Allan Balmain Alan R. Prescott Stephan Weidinger Hansjörg Baurecht Michael Kabesch Christian Gieger Young-Ae Lee Roger Tavendale Somnath Mukhopadhyay Stephen W. Turner Vishnu B. Madhok Frank M. Sullivan Caroline Relton John Burn Simon Meggitt Catherine H. Smith Michael A. Allen Jonathan N.W. N. Barker Nick J. Reynolds Heather J. Cordell Alan D. Irvine W.H. Irwin McLean Aileen Sandilands Padraic G. Fallon 《The Journal of allergy and clinical immunology》2013
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