摘要:

Cerebral atrophy and the decrease in cerebral blood flow (CBF) progress with advancing age. Which of them takes first place, the changes in CBF or cerebral atrophy? We investigated longitudinal changes in CBF and cerebral atrophy in 14 patients with ischemic cerebrovascular disease (CVD): 11 patients with supratentorial lacunar infarction and 3 with carotid transient ischemia attack who were neurologically stable during the 1-3 years of observation. Cerebral atrophy was estimated by the brain atrophy index (BAI): one of the CT area measurement methods, and CBF was measured using the 133Xe inhalation technique. While significant progression of cerebral atrophy was observed, there was no significant change in CBF. Cerebral atrophy precedes the change in CBF and CVD.

ISSN:0304-324X    

DOI:10.1159/000213300

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The glutathione reductase activity was estimated in brain and liver of male mice of different age groups fed on butylated hydroxy anisole (BHA), propyl gallate (PG) and α-tocopherol (TP). A significant increase in glutathione reductase activity was observed with TP during all the phases (pre-reproductive, reproductive and post-reproductive). Antioxidants enhanced the enzyme activity in both the tissues with the exception of BHA in brain during reproductive and PG in liver during pre-reproductive phases respectively. The enhanced reducing potential of the cell in terms of added bioconversion of GSSG to GSH may account for increase in longevity on antioxidant treatment

ISSN:0304-324X    

DOI:10.1159/000213301

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The lead content of mouse femurs increased by 83% between 76 and 958 days of age with values ranging from 0.192 to 1.78 ng Pb/mg dry weight. These values are remarkably lower than in previous reports for the lead content of bone. The lead content of mouse liver showed no aging-related trend with values ranging from 0.00823 to 0.0149 ng/mg dry weight. Bone density, calcium and collagen content were not related to the lead content. We conclude that while bone lead content is very low in mice, it increases with aging but does not appear to be related to the osteopenia which develops in the C57BL/6J male mouse.

ISSN:0304-324X    

DOI:10.1159/000213302

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Mitochondnal abnormality in the skeletal muscles of 13 patients with myotonic dystrophy was analyzed by both histo-chemical and molecular biologic methods. Nine of 13 patients had ragged-red fibers (50 ± 116 per 10,000 muscle fibers, mean ± SD), and 10 patients had cytochrome c oxidase-negative fibers (41 ± 90 per 10,000 muscle fibers). Southern blot analysis detected no mitochondrial DNA deletions, while PCR revealed multiple mitochondrial DNA deletions in all the specimens. Direct sequencing of one of the deleted mitochondrial DNAs disclosed that the junctional sequence of a 3,460-bp deletion involved a 6-bp directly repeated sequence (5’-TA-GAAG-3’) flanked by C-rich regions located on the C03 gene and the ND5 gene. Quantitative analysis of PCR amplified deleted mitochondrial DNAs revealed that the amount of deleted mitochondrial DNAs had positive correlation both with the frequencies of ragged-red fibers and cytochrome c oxidase-negative fibers. Although deleted mitochondrial DNAs were observed even in controls above age 30, the mean amount of deleted mitochondrial DNAs in patients with myotonic dystrophy was significantly higher than in controls. Moreover, the increase of deleted mitochondrial DNAs with aging was more marked in myotonic dystrophy than in controls. These results suggest that increased mitochondrial DNA deletions and consequent impairment of mitochondrial function contribute to the pathophysiology of myotonic dys

ISSN:0304-324X    

DOI:10.1159/000213303

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

A mathematical model of survivorship kinetics is presented. It takes into account both deterministic and stochastic aspects of survival curves. Earlier reports [Piantanelli: Arch Gerontol Geriatr 1986;5:107–118; Piantanelli: Ann NY Acad Sci 1988; 521:99–109] described a model capable of making distinct predictions on the mean and standard deviation of an index of physiological function, fitting data even in the tail of survivorship curves, and accounting for the selection of the cohort at advanced ages. However, it contains four parameters whose biological interpretation is unclear. In the present paper we propose a modification of the model which maintains the main characteristics of the previous one and, in addition, results in two significant improvements. First, the number of free parameters is reduced to only two, making much easier both their estimation and interpretation, particularly when the model is applied to data from various animal groups manipulated in different ways. Second, it is possible to relate the parameters to well-defined deterministic and stochastic factors: specifically, a deterministic component describing the environmental and genetic influence on physiological functions, and a stochastic component representing the fluctuating interactions of the living organism and its environm

ISSN:0304-324X    

DOI:10.1159/000213304

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Two age groups – young (19–35) and elderly (70–91) – were compared with respect to natural killer (NK) cytotoxic activity. In both groups, low and high NK responders could be distinguished. Low NK responders constituted about 70% of all elderly and 40% of young individuals. The differences in the magnitude of NK activity among the young and elderly groups could only be observed when peripheral-blood mononuclear cells but not peripheral-blood lymphocytes were used as effector cells in a 51Cr release assay. Experiments with removal or addition of graded numbers of monocytes showed that these cells were responsible for the low level of NK activity in both the young and elderly low NK res

ISSN:0304-324X    

DOI:10.1159/000213305

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Spontaneous photon emission (chemiluminescence, CL) as a monitor of free radical evolution in Drosophila melanogaster which had been maintained at 25 or 30°C for 5 days after emergence was measured. When maintained at 30°C the fly CL intensity was stronger than at 25°C. Under the condition of the higher temperature, the fly life span was shorter (mean life span = 29 days at 30°C and 63 days at 25°C), and oxygen consumption (3.7 μl/mg·h at 25°C, 4.9 μl/mg·h at 30°C) and the mobility (movement distance = 25 mm/min at 25°C, 700 mm/min at 30°C) increased, together with augmentation of phospholipid hydroperoxide in the fly total lipids. The CL spontaneously emitted from fly homogenate was decreased by the free radical scavengers both in experimtens in vivo and in vitro. The hypothesis is proposed that as the oxygen metabolism grows active, the chemiluminescent reactions that involve oxygen-dependent free radical metabolism, including membrane phospholipid hydroperoxidation, contribute to the acceleration of senescence o

ISSN:0304-324X    

DOI:10.1159/000213306

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

Drosophila melanogaster flies climb up the sides of their vial after having been submitted to a mechanical stimulation; that ability is impaired at older ages. The climbing activity (CLI) of flies kept at various gravity levels (1,3 and 5 g) has been measured throughout life, in cross-sectional studies. Hypergravity had no effect on CLI at young age, but older flies kept in hypergravity displayed lower scores than flies kept at 1 g. Results are discussed in relation with the hypothesis of increased aging rate in hypergravity.

ISSN:0304-324X    

DOI:10.1159/000213307

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The paths of young, middle-aged and old Drosophila melanogaster flies, kept at various gravity levels (1–5 g) throughout life, have been recorded in a cross-sectional study. Aging flies exhibit more sinuous paths and do not move as far away from their release point as younger ones. These age-related changes in the patterns of movement are expressed at younger ages in flies submitted to hypergravity. As for the climbing activity experiment, the patterns of movement do not clearly vary with the gravity level at young age. Results are discussed in relation to the hypothesis of increased aging rate in hypergravity.

ISSN:0304-324X    

DOI:10.1159/000213308

出版商:S. Karger AG    

年代:1992

数据来源: Karger

摘要:

The spontaneous locomotor activity (SLA) of Drosophila melanogaster flies kept at various gravity levels (1–5 g) was recorded in both longitudinal and cross-sectional experiments. No gravity level effect could be detected in the longitudinal one, probably because these flies were allowed (for technical reasons) to rest at 1 g for 15 % of their life. By contrast, flies kept at 5 g in the cross-sectional experiment had lower SLA scores at middle and old age than both 1 and 3 g-kept flies. The results of this series of experiments on hypergravity (HG) effects on three forms of locomotor activity (climbing activity, patterns of movement and SLA) allow to conclude that aging is accelerated in HG, even if no longevity decrease could be detected in the 1–4 g range.

ISSN:0304-324X    

DOI:10.1159/000213309

出版商:S. Karger AG    

年代:1992

数据来源: Karger