摘要:

The intestinal permeability of aging rats to various molecular weight species of polyethylene glycol 400 (PEG 400) was studied. Animals received a bolus of PEG 400 by oral gavage and urine was collected for 6 h to assess its rate of absorption. Quantitation by gas liquid chromatography revealed that total urinary excretion of PEG 400 increased with aging. 34-week-old rats excreted 34.3% of the administrated dose while 43.6% was excreted in the urine by rats 133 weeks of age. This effect was more pronounced with the higher molecular weight PEG since excretion of the lower molecular weight PEG 282 decreased by 10.5 % while PEG 634 excretion increased by 11.4% with aging. The increased permeability of the intestinal tract to higher molecular weight species of PEG may indicate that the intestinal protective barrier to the absorption of potentially harmful environmental substances may be less efficient in aging animals. If similar findings are found in aging humans, they may indicate increased potential for absorption of large antigenic or carcinogenic compounds from the intestinal lumen.

ISSN:0304-324X    

DOI:10.1159/000212694

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Binding in 14 ligand membrane receptor pairs and choline acetyltransferase activity were studied at 4-hour intervals during a 24-hour cycle (12:12 light:dark). Cortex, hippocampus, cerebellum, striatum and brainstem were prepared from 3-, 12- and 24-month-old male rats. Cholinergic, α- and β-adrenergic, dopaminergic, serotonergic, gabaergic and opiate binding were determined. In the aged animals, the times of the binding maxima are no longer locked to the same time of the light:dark cycle, and the cycle phases themselves are shifted in comparison to those of the young and adult group. Cycle amplitudes were smallest in the 12-month-old rats, increasing significantly in the 24-month group. The age changes in the overall (24-hour) means fall into 4 different patterns, none of which shows a linear age-related decrease. This points out the great importance of including an adult group (12 months) in all ageing studies on small mammal

ISSN:0304-324X    

DOI:10.1159/000212695

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The predictive values of the equations of Moore et al. and Hume and Weyers and the measured values of body composition were compared in healthy, carefully selected aged and young subjects of both sexes. In the case of young subjects, these prediction equations seem to be adequate, even if this could not be affirmed with certainty by our results. The equations of Moore et al. were found not to be adequate for elderly males, while they were only suitable for the determination of intracellular components in elderly females.

ISSN:0304-324X    

DOI:10.1159/000212696

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The increase in autofluorescence (AF) of human skin fibroblasts during their in vitro ageing and growth inhibition was investigated by means of flow cytophotometry. The cellular AF of in vitro ageing cultures increased while the relative number of (3H)-thymidine incorporating cells decreased. Therefore, the rate of accumulation of cellular AF during in vitro ageing of the cultures is inversely related to the proliferation rate of the culture. The rates of increase of AF varied widely among the cell strains, being the highest in cells from patients with Werner’s syndrome. Upon growth inhibition in a confluent culture the net rates of increase of cellular AF were found to vary widely among the cell strains. The respective net rates of increase of AF of the cells from patients with Werner’s syndrome and the Spielmeyer-Vogt syndrome were within the range covered by the normal cell strains. The ultrastructure of the bright AF cells from patients with Werner’s syndrome and the Spielmeyer-Vogt syndrome differed from the ultrastructure of AF cells from control persons with regard to the morphology of their residual bodies, those from the patients contained more multilamellar and multivesicular structures. In sorted non-AF cells vitamin E was found to completely inhibit the accumulation of AF without affecting the formation of ‘residual bodies’. We infer that cellular AF is caused by lipid peroxidative reactions and that the accumulation of AF is due to a decrease in cellular prolifera

ISSN:0304-324X    

DOI:10.1159/000212697

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The effects of aging on active Na+ extrusion and oxygen consumption associated with it were studied in rat kidney cortex cells. It was found that (a) the active extrusion of Na+ undergoing Na/K exchange and the active extrusion of Na+ with Cl–– and water were diminished in old rats (24 months) as compared with young rats (3 months); (b) the oxygen consumption associated with each of the two active mechanisms of Na+ extrusion was also diminished in the old rats; (c) the calculated turnover rate of the Na/K pump was significantly lower for the old r

ISSN:0304-324X    

DOI:10.1159/000212698

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

100 consecutive endoscopies in elderly patients referred with symptoms after previous gastric surgery are reviewed. 57% showed positive findings, and the procedure was found particularly useful in making definitive diagnoses in patients presenting with dyspepsia and upper gastro-intestinal bleeding. The incidence of gastric carcinoma was low, and the findings did not support routine repeated endoscopies in elderly patients.

ISSN:0304-324X    

DOI:10.1159/000212699

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

These studies were undertaken to investigate the effect of acute bacterial infections on the absolute number of peripheral blood lymphocytes (PBL) in an elderly population and to evaluate the prognostic significance of a decreased number of PBL in critically ill aged patients. The results show that a significant lymphopenia develops in elderly patients during the course of an acute bacterial infection whereas the same type of acute illness has no effect on the PBL count of younger subjects. The lymphopenia is not related to a particular localization of the infection nor to the type of bacterial pathogen. The prognosis of the bacterial infection is closely linked to the severity of the lymphocyte depletion and its outcome can nearly be predicted by monitoring the variation of the number of circulating lymphocytes during the early course of the disease.

ISSN:0304-324X    

DOI:10.1159/000212700

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

We examined the presenting features, clinical course and prognosis in relation to age in 121 patients with primary biliary cirrhosis (PBC) for a mean follow-up of 4.6 years. 35 patients (29%) were over age 65 years at presentation/detection. There was a higher proportion of patients asymptomatic of liver disease in the older (over 65 years old) than younger (under 65 years old) group. The clinical features of PBC were less marked in the older patients both in number of symptoms (p < 0.05) and in progression of serum bilirubin, a marker of prognosis (p < 0.001). There was no difference in liver-related mortality between old and young patients during the follow-up period. Overall mortality in patients with PBC presenting over age 65 was no different from age- and sex-matched controls.

ISSN:0304-324X    

DOI:10.1159/000212701

出版商:S. Karger AG    

年代:1985

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000212702

出版商:S. Karger AG    

年代:1985

数据来源: Karger

ISSN:0304-324X    

DOI:10.1159/000212703

出版商:S. Karger AG    

年代:1985

数据来源: Karger