519 resultados para Gerontology.


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Reaction between 5-(4-amino-2-thiabutyl)-5-methyl-3,7-dithianonane-1, 9-diamine (N3S3) and 5- methyl-2,2-bipyridine-5-carbaldehyde and subsequent reduction of the resulting imine with sodium borohydride results in a potentially ditopic ligand (L). Treatment of L with one equivalent of an iron( II) salt led to the monoprotonated complex [Fe(HL)](3+), isolated as the hexafluorophosphate salt. The presence of characteristic bands for the tris( bipyridyl) iron( II) chromophore in the UV/vis spectrum indicated that the iron( II) atom is coordinated octahedrally by the three bipyridyl (bipy) groups. The [Fe( bipy) 3] moiety encloses a cavity composed of the N3S3 portion of the ditopic ligand. The mononuclear and monomeric nature of the complex [Fe(HL)](3+) has been established also by accurate mass analysis. [Fe(HL)](3+) displays reduced stability to base compared with the complex [Fe(bipy)(3)](2+). In aqueous solution [Fe(HL)](3+) exhibits irreversible electrochemical behaviour with an oxidation wave ca. 60 mV to more positive potential than [Fe(bipy)(3)](2+). Investigations of the interaction of [Fe(L)](2+) with copper( II), iron( II), and mercury( II) using mass spectroscopic and potentiometric methods suggested that where complexation occurred, fewer than six of the N3S3 cavity donors were involved. The high affinity of the complex [Fe(L)](2+) for protons is one reason suggested to contribute to the reluctance to coordinate a second metal ion.

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Objective: To investigate the influence of age and preparation level on postural muscle activation and step completion time during a rapid step task. Design: Postural muscle onset times (EMG) and ground reaction forces were recorded from healthy young (n = 20, age 21 +/- 3 years) and older (n = 25, age 71 +/- 5 years) female adults during a choice reaction-time stepping paradigm. Main outcome measures: Onset times of six trunk and hip muscles, reaction time and components of the step (weight shift time, step time and task time) were recorded. Results: Muscle activation was delayed and movement time was lengthened in both young and older adults when poorly prepared for a stepping task. While reduced preparation did not influence older adults to a greater extent than young adults, the slowest step response and completion time was evident in older adults when poorly prepared to move. Conclusions: A late postural response when poorly prepared to move may be a contributing factor to an increased risk of overbalancing in older adults. Future assessment of and intervention to improve postural stability in older adults should be expanded to incorporate tasks performed at various levels of preparation.

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This study investigated the influence of a concurrent cognitive task on the compensatory stepping response in balance-impaired elders and the attentional demand of the stepping response. Kinetic, kinematic and neuromuscular measures of a forward recovery step were investigated in 15 young adults, 15 healthy elders and 13 balance-impaired elders in a single task (postural recovery only) and dual task (postural recovery and vocal reaction time task) situation. Results revealed that reaction times were longer in all subjects when performed concurrently with a compensatory step, they were longer for a step than an in-place response and longer for balance-impaired older adults compared with young adults. An interesting finding was that the latter group difference may be related to prioritization between the two tasks rather than attentional demand, as the older adults completed the step before the reaction time, whereas the young adults could perform both concurrently. Few differences in step characteristics were found between tasks, with the most notable being a delayed latency and reduced magnitude of the early automatic postural response in healthy and balance-impaired elders with a concurrent task. (C) 2002 Elsevier Science B.V. All rights reserved.

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Background and Purpose Previous research regarding the symmetry of trans-tibial amputees has examined weight distribution and various gait parameters between prosthetic and sound limbs. However, to date, no known research has determined if asymmetry is present in the strength of the hip abductor muscles or if correlations exist between these categories of symmetry. The purpose of the present study was, therefore, to document asymmetry present in stance, strength and gait measures, and to determine the relationship between these variables. Method Twenty-three elderly, unilateral trans-tibial amputees stood on two adjacent forceplates whilst the weight distribution and standard deviation (SD) of the anterior-posterior and the medio-lateral centre of pressure excursion (COPE) under each limb was recorded during four 40 s trials: quiet stance (QS), with eyes open and eyes closed; and even stance (ES), with eyes open and eyes closed. Gait measures (velocity, cadence, step and stride lengths, stance:swing ratio and period of double support) over 10 m of fast, yet safe walking and measures of the strength of hip abductor muscles were also obtained by use of a stride analyser and a dynamometer, respectively. Results No significant differences were found between QS and ES measures. However, significantly more weight was taken on the sound limb than on the amputated limb. Notably, more anterior-posterior movement occurred under the sound limb than the amputated limb, with this becoming more apparent with the eyes closed. Movement in the medio-lateral direction was found to be the same between sides. No differences in muscle strength or gait measures between limbs were demonstrated. However. strong hip abductor muscles were correlated with increased weight-bearing on the amputated limb, improved gait parameters and reduced medio-lateral COPE under the amputated limb. Conclusions This research confirms the asymmetrical nature of amputee stance and demonstrates symmetry of strength and gait measures between limbs. The correlations between hip abductor muscle strength, weight distribution and gait measures illustrates the importance of pre- and postoperative training of these muscles. Copyright © 2002 Whurr Publishers Ltd.

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The validity of a brief self-report screening measure for elder abuse was examined on a nationally representative sample of more than 12,000 older women it? the baseline survey of the Australian Longitudinal Study on Women's Health. The screening instrument was a modification Of the Hwalek-Sengstock Elder Abuse Screening Test. Construct validity was examined using factor analysis and correlation with a wide range of sociodemographic, psychological. and health-related variables. Four factors, each of three items, were identified representing the following domains: Vulnerability, Dependence, Dejection, and Coercion. The Vulnerability and Coercion factors had the highest face validity for abuse and demonstrated moderate to good construct validity. The six items comprising these factors may provide a simple screening tool for elder abuse The identified correlates of abuse indicators have the potential to enhance policy development, screening, intervention, and carer support programs.

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With evidence of increasing accident risk due to age-related declines in health and cognition affecting driver performance, there is a need for research promoting safe mobility of older people. The present study aimed to identify transport options and licensing issues for a group of older people in an Australian community. Ninety-five participants aged 75 and over were interviewed about their driving status and accident record and tested for cognitive ability. After stratification on cognitive level and driver status (current, ex-driver or non-driver), 30 were selected for further in-depth interviews concerning demographics, licence status and impact of change, travel options available and used, and travel characteristics. Considerable reliance on the motor vehicle as the mode of transport and the decision to cease driving were major quality-of-life issues. There was little evidence of planning and support in making the decision to stop driving. Some differences in transport decisions on the basis of cognitive level were evident; however, people with severely compromised cognitive ability (and, therefore, unable to give informed consent) had been excluded. The study suggested the need for resources to assist older people/carers/health professionals to plan for the transition from driver to non-driver and to manage alternative transport options more effectively

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The aim of this study was to assess the variation between neuropathologists in the diagnosis of common dementia syndromes when multiple published protocols are applied. Fourteen out of 18 Australian neuropathologists participated in diagnosing 20 cases (16 cases of dementia, 4 age-matched controls) using consensus diagnostic methods. Diagnostic criteria, clinical synopses and slides from multiple brain regions were sent to participants who were asked for case diagnoses. Diagnostic sensitivity, specificity, predictive value, accuracy and variability were determined using percentage agreement and kappa statistics. Using CERAD criteria, there was a high inter-rater agreement for cases with probable and definite Alzheimer's disease but low agreement for cases with possible Alzheimer's disease. Braak staging and the application of criteria for dementia with Lewy bodies also resulted in high inter-rater agreement. There was poor agreement for the diagnosis of frontotemporal dementia and for identifying small vessel disease. Participants rarely diagnosed more than one disease in any case. To improve efficiency when applying multiple diagnostic criteria, several simplifications were proposed and tested on 5 of the original 210 cases. Inter-rater reliability for the diagnosis of Alzheimer's disease and dementia with Lewy bodies significantly improved. Further development of simple and accurate methods to identify small vessel lesions and diagnose frontotemporal dementia is warranted.

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This study was conducted to determine the effect of increasing age on four shoulder movements and to explore the need for normative data for shoulder range of motion (ROM) in people aged 50 years and older. Forty-one participants were conveniently recruited according to four age categories: 50-59 years, 60-69 years, 70-79 years and 80 years and over. Goniometric measurement of bilateral active and passive ROM for flexion, abduction, internal rotation and external rotation was analysed using paired sample t-tests and compared with the norms of the American Academy of Orthopaedic Surgeons (AAOS) using one sample t-tests. Passive ROM was greater than active ROM for all movements (p

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Purpose: This study aimed to identify the constituents and conceptual characteristics of the quality of life (QOL) of Chinese elderly stroke survivors. living in the community in Hong Kong. Method: A triangulated approach was used to identify the QOL components for this population. This process involved a comparison of QOL components gathered from three different methods, namely, focus group interviews, review of the literature and the contents of the generic Hong Kong Chinese version of the World Health Organization Quality of Life Scale (CWHOQOL-HK). Five health professionals were involved in the comparison process. A percentage of inter-judge agreement was used to determine the reliability of the comparisons made between the judges. Results: This study identified 36 components considered to contribute to the QOL of Chinese elderly stroke survivors in Hona Kong. The conceptual characteristics of their QOL generally concurred with those identified in the literature. Conclusion: Both similarities and differences were found in the QOL components identified in this study when compared to those identified in studies of Western populations who are elderly and had a stroke. The contents of the CWHOQOL-HK scale were found to lack adequacy in representing the QOL of Chinese elderly stroke survivors in Hong Kong. Recommendations are given, based on the findings of this study, to overcome this limitation for its application as a QOL measure for this population.

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Objective: To determine item, subscale and total score agreement on the Frenchay Activities Index (FAI) between stroke patients and proxies six months after discharge from rehabilitation. Design: Prospective study design. Setting/subjects: Fifty patient-proxy pairs, interviewed separately, in the patient's residence. Main outcome measures: Modified FAI using 13 items. Individual FAI items, subscales and total score agreement as measured by weighted kappa and intraclass correlation coefficients (ICC). Results: Excellent agreement was found for the total FAI (ICC 0.87, 95% confidence interval (CI) 0.78-0.93), and domestic (ICC 0.85, 95% CI 0.73-0.91) and outdoor (ICC 0.87, 95% CI 0.78-0.95) subscales, with moderate agreement found for the work/leisure subscale (ICC 0.63, 95% CI 0.34-0.78). For the individual FAI items, good, moderate, fair and poor agreement was found for five, three, four and one item, respectively. The best agreement was for objective items of preparing meals, washing-up, washing clothes, shopping and driving. The poorest agreement was for participation in hobbies, social outings and heavy housework. Scoring biases associated with patient or proxy demographic characteristics were found. Female proxies, and those who were spouses, scored patients lower on domestic activities; male patients, and those who were younger, scored themselves higher on outdoor activities and higher patient FIM scores were positively correlated with higher FAI scores. Conclusions: While total and subscale agreement on the FAI was high, individual item agreement varied. Proxy scores should be used with caution due to bias.

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OTseeker (Occupational Therapy Systematic Evaluation of Evidence) is a new resource for occupational therapists that has been designed with the principle aim of increasing access to research to support clinical decisions. It contains abstracts of systematic reviews and quality ratings of randomized controlled trials (RCTs) relevant to occupational therapy. It is available, free of charge, at www.otseeker.com. This paper describes the OTseeker database and provides an example of how it may support occupational therapy practice.

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Compression amplification significantly alters the acoustic speech signal in comparison to linear amplification. The central hypothesis of the present study was that the compression settings of a two-channel aid that best preserved the acoustic properties of speech compared to linear amplification would yield the best perceptual results, and that the compression settings that most altered the acoustic properties of speech compared to linear would yield significantly poorer speech perception. On the basis of initial acoustic analysis of the test stimuli recorded through a hearing aid, two different compression amplification settings were chosen for the perceptual study. Participants were 74 adults with mild to moderate sensorineural hearing impairment. Overall, the speech perception results supported the hypothesis. A further aim of the study was to determine if variation in participants' speech perception with compression amplification (compared to linear amplification) could be explained by the individual characteristics of age, degree of loss, dynamic range, temporal resolution, and frequency selectivity; however, no significant relationships were found.

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Ageing results in a progressive, intrinsic and generalised imbalance of the control of regulatory systems. A key manifestation of this complex biological process includes the attenuation of the universal stress response. Here we provide the first global assessment of the ageing process as it affects the heat shock response, utilising human peripheral lymphocytes and cDNA microarray analysis. The genomic approach employed in our preliminary study was supplemented with a proteomic approach. In addition, the current study correlates the in vivo total antioxidant status with the age-related differential gene expression as well as the translational kinetics of heat shock proteins (hsps). Most of the genes encoding stress response proteins on the 4224 element microarray used in this study were significantly elevated after heat shock treatment of lymphocytes obtained from both young and old individuals albeit to a greater extent in the young. Cell signaling and signal transduction genes as well as some oxidoreductases showed varied response. Results from translational kinetics of induction of major hsps, from 0 to 24 It recovery period were broadly consistent with the differential expression of HSC 70 and HSP 40 genes. Total antioxidant levels in plasma from old individuals were found to be significantly lower by comparison with young, in agreement with the widely acknowledged role of oxidant homeostasis in the ageing process. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.

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