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1.
Conserv Biol ; 22(2): 417-27, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18402584

RESUMO

In recent centuries bird species have been deteriorating in status and becoming extinct at a rate that may be 2-3 orders of magnitude higher than in prehuman times. We examined extinction rates of bird species designated critically endangered in 1994 and the rate at which species have moved through the IUCN (World Conservation Union) Red List categories of extinction risk globally for the period 1988-2004 and regionally in Australia from 1750 to 2000. For Australia we drew on historical accounts of the extent and condition of species habitats, spread of invasive species, and changes in sighting frequencies. These data sets permitted comparison of observed rates of movement through the IUCN Red List categories with novel predictions based on the IUCN Red List criterion E, which relates to explicit extinction probabilities determined, for example, by population viability analysis. The comparison also tested whether species listed on the basis of other criteria face a similar probability of moving to a higher threat category as those listed under criterion E. For the rate at which species moved from vulnerable to endangered, there was a good match between observations and predictions, both worldwide and in Australia. Nevertheless, species have become extinct at a rate that, although historically high, is 2 (Australia) to 10 (globally) times lower than predicted. Although the extinction probability associated with the critically endangered category may be too high, the shortfall in realized extinctions can also be attributed to the beneficial impact of conservation intervention. These efforts may have reduced the number of global extinctions from 19 to 3 and substantially slowed the extinction trajectory of 33 additional critically endangered species. Our results suggest that current conservation action benefits species on the brink of extinction, but is less targeted at or has less effect on moderately threatened species.


Assuntos
Biodiversidade , Aves/fisiologia , Conservação dos Recursos Naturais/métodos , Extinção Biológica , Animais , Bases de Dados Factuais , Agências Internacionais , Dinâmica Populacional
2.
J Am Geriatr Soc ; 39(6): 549-54, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2037744

RESUMO

The extent to which exercise can delay the normal decline in physical performance associated with aging is unknown. We examined the impact of 2 years of supervised exercise on cardiovascular fitness, flexibility, and strength in a group of elderly (age 65-74) veterans. Seventy-five patients exercised 3 days/week for 90-minute sessions emphasizing aerobic, flexibility, and strength development. Thirty-six (47%) completed 2 years of a voluntary supervised exercise program (n = 25 with complete data). Over a 2-year follow-up period, cardiovascular outcome variables improved significantly: metabolic equivalents increased 20% (7.4 +/- 2.2 to 9.0 +/- 2.4, P less than 0.001) and submaximal heart rate decreased 7% (68.5 +/- 8.0 to 63.6 +/- 8.4 beats/minute, P = 0.02). Resting heart rate decreased 8% (131.4 +/- 14.8 to 121.0 +/- 18.5 beats/minute, P = 0.06), but this difference did not reach statistical significance. Flexibility, measured by hamstring length, improved 11% (57.5 +/- 15.1 to 64.0 +/- 11.1 degrees, P = 0.02). Strength variables did not improve. The study indicates that improvements in cardiovascular function and flexibility achieved by the elderly in the early stages of an exercise program can be maintained for at least 2 years.


Assuntos
Envelhecimento/fisiologia , Exercício Físico/fisiologia , Idoso , Idoso de 80 Anos ou mais , Assistência Ambulatorial , Índice de Massa Corporal , Peso Corporal/fisiologia , HDL-Colesterol/sangue , Feminino , Seguimentos , Frequência Cardíaca/fisiologia , Humanos , Masculino , Músculos/fisiologia
3.
J Am Geriatr Soc ; 39(10): 986-92, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1918786

RESUMO

The extent to which exercise can delay the normal decline in physical performance associated with aging is unknown. We examined the impact of 2 years of supervised exercise on cardiovascular fitness, flexibility, and strength in a group of elderly (age 65-74) veterans. Seventy-five patients exercised 3 days/week for 90-minute sessions emphasizing aerobic, flexibility, and strength development. Thirty-six (47%) completed 2 years of a voluntary supervised exercise program (n = 16-25 with complete data). Over a 2-year follow-up period, cardiovascular outcome variables improved significantly: metabolic equivalents increased 20% (7.4 +/- 2.2 to 9.0 +/- 2.4, P less than 0.001) and submaximal heart rate decreased 7% (131.4 +/- 14.8 to 121.0 +/- 18.5 beats/minute, P = 0.06). Resting heart rate decreased 8% (68.5 +/- 8.0 to 63.6 +/- 8.4 beats/minute, P = 0.02) but this difference did not reach statistical significance. Flexibility, measured by hamstring length, improved 11% (57.5 +/- 15.1 to 64.0 +/- 11.1 degrees, P = 0.02). Strength variables did not improve. The study indicates that improvements in cardiovascular function and flexibility achieved by the elderly in the early stages of an exercise program can be maintained for at least 2 years.


Assuntos
Exercício Físico/fisiologia , Aptidão Física/fisiologia , Veteranos , Idoso , Índice de Massa Corporal , Peso Corporal/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Colesterol/sangue , Feminino , Seguimentos , Frequência Cardíaca/fisiologia , Humanos , Masculino
4.
J Am Geriatr Soc ; 44(10): 1226-31, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8856003

RESUMO

OBJECTIVE: To examine 5-year trends in measures of physical performance, and the impact of disease upon performance, in three domains: cardiovascular fitness, musculo-skeletal strength, and flexibility among older adults participating in a medically supervised exercise program. DESIGN: Longitudinal analyses of data obtained in an observational cohort study. SETTING: Department of Veterans Affairs Medical Center in Durham, North Carolina. PARTICIPANTS: Seventy-three community-dwelling veterans between 64 and 90 years of age. INTERVENTION: Voluntary participation in a medically supervised outpatient exercise program meeting 3 days per week for 90 minutes per session. MAIN OUTCOME MEASURES: Changes over time in cardiovascular fitness, musculoskeletal strength, and flexibility. RESULTS: Forty-nine percent of the original study participants remained in the program for a full 5 years. They had lower baseline rates of cardiorespiratory and musculoskeletal diseases than did the dropouts. Dropouts were significantly more impaired in baseline measures of cardiovascular fitness (P = .038) and strength (P = .007). Changes over time for cardiovascular fitness and strength were similar. Only linear (P < .05) and quadratic time (P < .001) were significant. Only linear time was significant for measures of flexibility (P < .05). Baseline cardiorespiratory disease, baseline musculoskeletal disease, and interaction terms were not significant. Overall, measures of physical performance demonstrated gradual improvement for 2 to 3 years, followed by a gradual decline in performance irrespective of baseline disease status. CONCLUSION: Older adults who exercise regularly, including those with multiple chronic diseases, can achieve significant gains in measures of physical performance, and these gains can be sustained for 2 to 3 years.


Assuntos
Idoso de 80 Anos ou mais/fisiologia , Idoso/fisiologia , Exercício Físico , Aptidão Física , Doenças Cardiovasculares/prevenção & controle , Estudos de Coortes , Teste de Esforço , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Doenças Musculoesqueléticas/prevenção & controle , Fatores de Tempo , Veteranos
5.
J Am Geriatr Soc ; 37(4): 348-54, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2921457

RESUMO

Most studies that assess the effects of exercise in the elderly involve subjects who are in good health. The objective of this prospective longitudinal study was to examine the impact of exercise on cardiovascular fitness, flexibility, and strength in an elderly population that included chronically ill individuals. Patients were recruited initially from a population of veterans over 64 years of age who use a VA outpatient clinic as their regular source of care. The exercise intervention consisted of 90 minutes of exercise 3 days per week at 70% of the patient's maximal capacity. Activities included stationary cycling, stretching, weight training, and walking. Of 69 patients who began the program, 49 (71%) reached 4-month follow-up. Most patients completing follow-up (76%) had at least one chronic disease, such as arthritis, hypertension, or heart disease. Patients who dropped out were more likely to have multiple chronic illnesses than those who remained in the program. Average weekly attendance was 65% and was stable over time. Improvements in cardiovascular fitness at 4-month follow-up were significant: Metabolic equivalents increased from 7.1 +/- 2.3 to 8.3 +/- 2.6 (P less than .001), treadmill time increased from 8.5 +/- 3.8 to 11.2 +/- 4.2 minutes (P less than .001), submaximal heart rate decreased from 123.7 +/- 18.8 to 118.8 +/- 19.4 beats per minute (P less than .001) and resting heart rate decreased from 68.1 +/- 10.6 to 63.3 +/- 11.6 beats per minute (P = .005).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Idoso , Exercício Físico , Doença Crônica/epidemiologia , Metabolismo Energético , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Aptidão Física , Estudos Prospectivos
6.
J Gerontol A Biol Sci Med Sci ; 54(7): M335-42, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10462164

RESUMO

BACKGROUND: As exercise is associated with favorable health outcomes, impaired older adults may benefit from specialized exercise interventions to achieve gains in function. The purpose of this study was to determine the added benefit of a spinal flexibility-plus-aerobic exercise intervention versus aerobic-only exercise on function among community-dwelling elders. METHODS: We employed a randomized clinical trial consisting of 3 months of supervised exercise followed by 6 months of home-based exercise with telephone follow-up. A total of 210 impaired males and females over age 64 enrolled in this study. Of these, 134 were randomly assigned to either spinal flexibility-plus-aerobic exercise or aerobic-only exercise, with 116 individuals completing the study. Primary outcomes obtained at baseline, after 3 months of supervised exercise, and after 6 months of home-based exercise included: axial rotation, maximal oxygen uptake (VO2max); functional reach, timed-bed-mobility; and the Physical Function Scale (PhysFunction) of the Medical Outcomes Study SF-36. RESULTS: Differences between the two interventions were minimal. Overall change scores for both groups combined indicated significant improvement for: axial rotation (p=.001), VO2max (p=.0001), and PhysFunction (p=.0016). Secondary improvements were noted for overall health (p=.0025) and reduced symptoms (p=.0008). Differences between groups were significant only for VO2max (p=.0014) at 3 months with the aerobic-only group improving twice as much in aerobic capacity as the spinal flexibility-plus-aerobic group. Repeated measures indicated both groups improved during the supervised portion of the intervention but tended to return toward baseline following the home-based portion of the trial. CONCLUSIONS: Gains in physical functioning and perceived overall health are obtained with moderate aerobic exercise. No differential improvements were noted for the spinal flexibility-plus-aerobic intervention.


Assuntos
Exercício Físico , Coluna Vertebral/fisiologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio
7.
J Appl Gerontol ; 10(4): 469-85, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10115729

RESUMO

This study examined the impact of supervised exercise on the health status (measured by the Sickness Impact Profile [SIP]) and well-being (measured by the Psychological General Well-Being Index [PGWB]) of a sample of 43 elderly veterans. The intervention consisted of 90 minutes of exercise, 3 days per week at 70% of maximal capacity. Twenty-three (53%) participants completed a 1-year follow-up. The mean PGWB score increased significantly from 83.0 +/- 15.8 to 89.4 +/- 8.9 (p = .01). Cardiovascular fitness (measured by treadmill performance) increased significantly (p = .004). Baseline SIP scores were low (little dysfunction) and changed little. The study suggests that small but significant improvements in well-being accompany physiological benefits that the elderly experience with exercise.


Assuntos
Exercício Físico , Promoção da Saúde/métodos , Resultado do Tratamento , Veteranos/psicologia , Idoso , Atitude Frente a Saúde , Imagem Corporal , Coleta de Dados , Estudos de Avaliação como Assunto , Feminino , Nível de Saúde , Hospitais com 300 a 499 Leitos , Hospitais de Veteranos , Humanos , Masculino , North Carolina , Autoimagem
8.
J Interferon Res ; 1(2): 305-13, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6180061

RESUMO

Human lymphoblastoid cell-derived interferon-alpha has been purified by a combination of chromatography on controlled-pore glass 350, gel filtration on Ultrogel AcA 54 and hydrophobic chromatography on Phenyl-Sepharose CL-4B. Specific activities of greater than 10(7) units/mg have been obtained. Controlled-Pore Glass has the advantages of accommodating large volumes of induced medium in an "in-line" process giving high recoveries of interferon and removing most of any contaminating DNA.


Assuntos
Cromatografia em Gel/métodos , Interferons/isolamento & purificação , Células Cultivadas , DNA , DNA Viral , Eletroforese em Gel de Poliacrilamida , Humanos , Linfócitos , Simplexvirus/genética
9.
South Med J ; 87(5): S83-7, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8178209

RESUMO

In 1986 Gerofit, an exercise and health promotion program for older veterans, was established. This paper describes the program in detail by summarizing the patient assessment protocol, the exercise program, and program evaluation, as well as observational outcomes for up to 5 years of follow-up. Our data suggest that exercise provides older veterans with beneficial gains in function that are maintained for 5 years.


Assuntos
Exercício Físico , Promoção da Saúde/métodos , United States Department of Veterans Affairs/organização & administração , Idoso , Feminino , Seguimentos , Humanos , Masculino , Inovação Organizacional , Pacientes Desistentes do Tratamento , Estados Unidos , Veteranos
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