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1.
A reduction in muscle mass, with consequent decrease in strength and resistance, is commonly observed with advancing age. In this study we measured markers of oxidative damage to DNA, lipids and proteins, some antioxidant enzyme activities as well Ca2+ transport in sarcoplasmic reticulum membranes in muscle biopsies from vastus lateralis of young and elderly healthy subjects of both sexes in order to evaluate the presence of age- and sex- related differences. We found a significant increase in oxidation of DNA and lipids in the elderly group, more evident in males, and a reduction in catalase and glutathione transferase activities. The experiments on Ca2+ transport showed an abnormal functional response of aged muscle after exposure to caffeine, which increases the opening of Ca2+ channels, as well a reduced activity of the Ca2+ pump in elderly males. From these results we conclude that oxidative stress play an important role in muscle aging and that oxidative damage is much more evident in elderly males, suggesting a gender difference maybe related to hormonal factors.This revised version was published online in September 2005 with corrections to the Cover Date.  相似文献   
2.
The consequences of natural disasters on the social and health status of older people have not been deeply considered. The aim of this study was to evaluate the socioenvironmental and psychophysical conditions of an elderly population after a devastating earthquake. A randomly selected group of 332 older people (> or =64 years) was selected among 1548 eligible subjects living in the city of Nocera Umbra four months after an earthquake of 5.6 magnitude on the Richter scale. Three geriatricians evaluated the study subjects by means of a structured interview, and standardized scales, which considered physical and mental status, mood and anxiety, and self-perception of well-being, as well as the characteristics of family composition and social interactions. Of the study subjects, 11.1% lived alone, and 33.4% with the spouse only. Most were self-sufficient in the basic activities of daily life. Musculoskeletal diseases and hypertension were the most frequently observed pathologies in this geriatric population. In addition, 47.9% of the subjects lived in temporary houses; this group more frequently suffered from hypertension, and had a higher score of comorbidity as measured by Cumulative Illness Rating Scale (CIRS) compared to people who remained at home. People living in the pre-fabricated huts also showed a higher score on the Geriatric Depression Scale and the Hamilton scale for anxiety, and complained more often of their health status, evaluated as self-perception of well-being, when compared to the home dwellers. Although all the studied subjects suffered from the discomforts caused by the earthquake, the precariousness of living in temporary houses, whose structural characteristics do not take the needs of elderly subjects into account, could justify the higher distress experienced by persons housed in the huts. These observations suggest that, after natural disasters, emergency programs should be more adapted to elderly people, whose needs and expectations are often different from those of young adults.  相似文献   
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CONTEXT: A large body of experimental evidence suggests that in Alzheimer disease (AD) pathogenesis an important role is played by oxidative stress, but there is still a lack of data on in vivo markers of free radical-induced damage. OBJECTIVES: To evaluate levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative damage to DNA, in peripheral lymphocytes; to measure plasma concentrations of several nonenzymatic antioxidants; and to assess the relationships between any observed changes in lymphocyte DNA 8-OHdG content and plasma antioxidant levels in patients with AD and healthy aged control subjects. SUBJECTS: Forty elderly outpatients with AD and 39 healthy age- and sex-matched controls were studied. MAIN OUTCOME MEASURES: The level of 8-OHdG was determined in DNA extracted from lymphocytes and plasma levels of vitamin C, vitamin A, vitamin E, and carotenoids (zeaxanthin, beta-cryptoxanthin, lycopene, lutein, and alpha- and beta-carotene) were measured by high-performance liquid chromatography. RESULTS: Lymphocyte DNA 8-OHdG content was significantly higher and plasma levels of antioxidants (with the exception of lutein) were significantly lower in patients with AD compared with controls. In patients with AD, a significant inverse relationship between lymphocyte DNA 8-OHdG content and plasma levels of lycopene, lutein, alpha-carotene, and beta-carotene, respectively, was observed. CONCLUSIONS: Markers of oxidative damage are increased in AD and correlate with decreased levels of plasma antioxidants. These findings suggest that lymphocyte DNA 8-OHdG content in patients with AD reflects a condition of increased oxidative stress related to a poor antioxidant status.  相似文献   
5.
High-resolution real-time echotomography was used in a longitudinal study on 118 atherosclerotic plaques of the extracranial carotid tract with the aim of identifying those most likely to cause a cerebrovascular event. Seventy patients (average age 61 +/- 7 years), referred to our Clinical Vascular Laboratory because suffering from transient cerebral ischemic attacks (TIA), coronary heart disease (CHD, peripheral artery disease (PAD), or cervical bruits (CB), were followed up for two years. Medical treatment remained that of the referring physician. Ten patients suffered from clinical events caused by stroke, TIA, and/or carotid occlusion during the follow-up. The echostructural profile of the lesions most often correlated with the clinical event was characterized by a mixed or hard echogenic pattern, and irregular surface, and an initial vascular stenosis of more than 50%.  相似文献   
6.
BACKGROUND: Stroke is the third cause of death in older people living in Western countries. We tested the hypothesis that angiotensin-converting enzyme inhibitors (A-I) might affect short-term (30 day) mortality in older persons with severe acute ischemic stroke. METHODS: We analyzed data from a retrospective study including 475 consecutive older patients hospitalized for acute ischemic stroke. Mean age was 78.4 +/- 9.2 years; 58.2% were female. Stroke type was classified according to the Oxford Community Stroke Project (OCSP). RESULTS: Mortality rate was 28%. Thirty-two percent of patients were treated with A-I; mortality was 16.5% in patients treated compared with 33.3% in those not treated (chi(2) p =.001). The odds ratio for mortality in treated patients was: 0.47 (0.25-0.89) after full adjustment (age, sex, mean diastolic and systolic blood pressure, previous stroke and/or transient ischemic attack, congestive heart failure, atrial fibrillation, diabetes, hypertension, coronary heart disease, and previous treatment with A-I); 0.29 (0.09-0.89) in patients with altered level of consciousness after full adjustment; 0.60 (0.33-1.12) after adjustment for OCSP classification, age, and sex; and 0.30 (0.08-0.97) in total anterior circulation infarction stroke type after full adjustment. CONCLUSIONS: Our data suggest that treatment with A-I might reduce short-term mortality in older patients with acute ischemic stroke. Randomized clinical trials should confirm this possible specific effect of A-I.  相似文献   
7.
OBJECTIVE: To detect the main factors associated with the occurrence of specific geriatric syndromes (namely pressure sores, fecal incontinence, urinary incontinence and falls) in elderly patients during hospitalization. DESIGN: Observational prospective study. Setting: Eighty-one community and university hospitals throughout Italy. PARTICIPANTS: 13,729 patients aged 65 years and more, consecutively admitted to medical or geriatric acute wards during 20 months in the period between 1991 and 1998. MEASUREMENTS: Occurrence of pressure sores, fecal incontinence, urinary incontinence and falls during the stay in hospital. RESULTS: Pressure sores were already present in 3% of hospitalized subjects, fecal incontinence in 7.3%, while urinary incontinence, evaluated on a subgroup of total population (4,268 subjects), had a prevalence of 22.3%. During hospitalization (mean stay of 15 days), 74 subjects developed new pressure sores, 55 became fecal and 35 urinary incontinent, and 279 subjects had at least one episode of fall. In multivariate analyses, cognitive impairment, advanced age (85+ years), length of stay (more than 3 weeks) and severe disability were the main independent predictors of development of the four geriatric syndromes, with cognitive impairment as the most significant risk factor for all the four outcomes (OR 4.9, 95% CI 2.4-9.9 for pressure sores; OR 6.3, 95% CI 3.0-13.0 for fecal incontinence; OR 5.3, 95% CI 2.3-12.0 for urinary incontinence; OR 1.6, 95% CI 1.2-2.3 for falls). CONCLUSION: Very old people have a significant increased risk of several geriatric syndromes during the stay in hospital, particularly if it is long and they are cognitively impaired. A standardized comprehensive geriatric evaluation at admission could be helpful in detecting all subjects at risk and preventing the development of hospital-acquired geriatric syndromes.  相似文献   
8.
A large body of evidence supports a role of oxidative stress in Alzheimer disease (AD) and in cerebrovascular disease. A vascular component might be critical in the pathophysiology of AD, but there is a substantial lack of data regarding the simultaneous behavior of peripheral antioxidants and biomarkers of oxidative stress in AD and vascular dementia (VaD). Sixty-three AD patients, 23 VaD patients and 55 controls were included in the study. We measured plasma levels of water-soluble (vitamin C and uric acid) and lipophilic (vitamin E, vitamin A, carotenoids including lutein, zeaxanthin, beta-cryptoxanthin, lycopene, alpha- and beta-carotene) antioxidant micronutrients as well as levels of biomarkers of lipid peroxidation [malondialdehyde (MDA)] and of protein oxidation [immunoglobulin G (IgG) levels of protein carbonyls and dityrosine] in patients and controls. With the exception of beta-carotene, all antioxidants were lower in demented patients as compared to controls. Furthermore, AD patients showed a significantly higher IgG dityrosine content as compared to controls. AD and VaD patients showed similar plasma levels of plasma antioxidants and MDA as well as a similar IgG content of protein carbonyls and dityrosine. We conclude that, independent of its nature-vascular or degenerative-dementia is associated with the depletion of a large spectrum of antioxidant micronutrients and with increased protein oxidative modification. This might be relevant to the pathophysiology of dementing disorders, particularly in light of the recently suggested importance of the vascular component in AD development.  相似文献   
9.
The presence of a dense appearance of the horizontal part of the middle cerebral artery (the “dense middle cerebral artery sign”) was looked for on CT scans taken on admission in 90 consecutive patients with ischemic stroke in the carotid artery distribution. The outcome of the 14 patients with the sign was poorer than that of 76 patients without the sign (Odds ratio 4.3). We suggest that this sign could be a useful prognostic variable in the acute phase of an ischemic stroke.
Sommario è state ricercata retrospettivamente la presenza della immagine iperdensa del tratto orizzontale della cerebrale media (“dense middle cerebral artery sign”) negli esami TAC eseguiti in 90 pazienti consecutivi con sintomatologia riferibile ad ischemia acuta nel territorio del circolo carotideo. L'evoluzione clinica dei 14 pazienti in cui il segno della cerebrale media iperdensa è stato rilevato è stata peggiore degli altri 76 (Odds ratio 4.3). Gli autori suggeriscono che il rilievo di questo segno può rappresentare una utile indicazione prognostica precoce nei casi di ischemia cerebrale acuta.
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10.
The plasma levels and urinary excretions of (+/-) alpha-(benzoylamino)-4-[2-(diethylamino)ethoxy]-N, N-dipropyl-benzenepropanamide (tiropramide) and of some of its metabolites were studied in healthy volunteers after the following single-dose administrations of tiropramide hydrochloride: a) i.v. 50 mg, oral 100 mg or rectal 200 mg; b) i.v. 50 mg or i.m. 50 mg; c) oral 100, 200 or 400 mg. After i.v. bolus the plasma levels of tiropramide are consistent with a three-compartment open pharmacokinetic model. The steady-state volume of distribution is 221 l. The terminal elimination constant is 0.279 h-1 (t1/2 = 2.5 h). After i.m. injection the plasma levels increase rapidly (invasion t1/2 = 2 min) and then are similar to those found after i.v. bolus. After oral administration appreciable plasma levels are found after lag times of 18-27 min. They increase with an invasion t1/2 of 14-22 min. The peak is reached 1-1.7 h after administration and the elimination occurs with a constant of 0.20-0.23 h-1. After rectal administration appreciable plasma levels are found after a lag time of 11 min and increase with an invasion t1/2 of 6 min. The peak is reached at 2.2 h. The elimination constant is 0.21 h-1. Tiropramide and some of its metabolites can be determined in the urine by gas-liquid chromatography. The following percentages of the administered dose of tiropramide and tiropramide-related substances can be found in the 24-h urines. After i.v. bolus: 16.2; after i.m. injection: 17.0; after oral administration: 19.6; after rectal administration 13.1.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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