The pharmacological management of cognitive dysfunction in Alzheimer's disease.
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Acetylcholine↗
Biomedical subjects
M F Vandewoude
Publications and source records attributed to M F Vandewoude.
Effect of ageing and malnutrition on rat myocardium. I. The myocyte.
The effects of ageing and starvation on the rat myocardium were studied by morphometric methods. Since cardiac muscle is a tissue with a high level of anisotropy, methods based on the concept of vertical planes were used to describe quantitative alterations in the rat myocyte both at the cellular and ultrastructural level. During starvation rapid and important changes were noted, particularly in the transverse dimension of cells and organelles. The most striking change, however, was the immediate dilatation of the myocyte T-system, reflecting an adaptive interaction between the intra- and extracellular environment. At the same time exocytosis of intracellular components into the extracellular space of the T-system was observed. The ratio of mitochondria to myofibrils decreased progressively during starvation. Such a decrease, in general, may reach a point when cellular energy supply becomes compromised. A comparison between different regions of the heart showed no differences and it can be concluded that the morphological changes during starvation are the same, and equally distributed, in both ventricles. The changes described in the aged rat heart point in the direction of a hypertrophy of the aged myocyte. This leads to a lower ratio between surface and volume which finds its representation at the subcellular level in a more spherical shape of nuclei and mitochondria. Unlike what is seen in malnutrition, the mitochondrial/myofibril ratio is higher in the older rat. From the morphological point of view, the atrophy of malnutrition and the hypertrophy of ageing are opposed, but in both there is a change in the relationship of the myocyte to its environment which directly influences the substrate exchange capacity. This tends to protect the myocyte in starvation but jeopardizes the older cell.
Aging↗
Effect of ageing and malnutrition on rat myocardium. II. The microvasculature.
The modulating effects of ageing and malnutrition on rat myocardium were studied morphometrically with respect to the microvasculature. An increase in capillary density together with a decrease in capillary lumen cross-sectional area was noted during starvation. The important changes seen in the myocyte T-system were paralleled by a decreased diffusion distance for oxygen from the capillary lumen to the mitochondrion. The changes described in the aged rat heart point to an altered inter-relationship between parenchyma and vascularization with a lower capillary volume fraction and a greater diffusion distance from the capillary lumen to the mitochondrion; this is caused by hypertrophy of the aged myocyte. This reduction in capacity to exchange substrates is further reduced by the less developed T-system in the older myocyte.
Aging↗
Creatinine arm index as alternative for creatinine height index.
Nutritional assessment of elderly people is limited due to a lack of age-corrected standards. The objective of this study was to develop a new, more age-independent index for nutritional assessment by correcting the creatinine height index (CHI) for the age-induced changes in its variables. This might improve the differentiation between physiological reduction in muscle mass in elderly people and the changes induced by malnutrition. Seventy-four elderly and 100 young healthy volunteers were compared by anthropometric and biochemical-assessment variables. From the high correlation between total arm length and body length (r = 0.86; P less than 0.001) and the use of an alternative formula to calculate ideal body weight (IBW) from height and wrist circumference, a relatively age-independent estimate of IBW was determined. Creatinine arm index, as an adapted index of CHI, is proposed based on this age-independent IBW estimation and a specific creatinine coefficient for different age groups.
Adult↗
Open evaluation of amlodipine in the monotherapeutic treatment of systolic hypertension in the elderly.
The antihypertensive efficacy and safety of amlodipine (5-10 mg once daily for 10 weeks) was assessed in elderly patients with primary systolic hypertension (average sitting and standing systolic blood pressure > or = 160 mm Hg and diastolic blood pressure < or = 95 mm Hg). Interim analysis of data from 25 patients shows that amlodipine treatment produced significant decreases in sitting blood pressure (-26.8/-11.4 mm Hg; p < 0.05). Efficacy assessments after 8 weeks of therapy showed 15 of 21 (71.4%) evaluable patients were considered therapeutic successes with amlodipine (defined as a fall from baseline in sitting systolic blood pressure of > or = 20 mm Hg or to < or = 150 mm Hg with a fall of > or = 10 mm Hg). Of the six evaluable patients who were not considered therapeutic successes using this definition, three had clinically beneficial falls in systolic blood pressure of 16-18 mm Hg. Fourteen patients were considered therapy successes on the basis of assessments taken 48 h postdose at the end of the study. Investigators' overall impression of efficacy was excellent or good in 21 patients (84%). Amlodipine treatment had no significant effect on heart rate. Amlodipine was generally well tolerated, with no patients being withdrawn due to side effects. Investigators' evaluation of toleration was excellent or good in 22 patients (88%).
Aged↗
Blood viscosity parameters in coronary heart disease: effect of fish oil supplementation.
We have evaluated blood viscosity parameters in 20 men suffering from coronary heart disease (CHD) and in 15 control subjects. Whole blood viscosity at a standardized haematocrit of 45% was significantly increased in the CHD-patients, both at low (p less than 0.001) and high (p less than 0.05) shear rate. The increased whole blood viscosity in these patients was explained by an increased plasma viscosity (p less than 0.01), while the erythrocyte suspension viscosity values at a standardized haematocrit of 70%, reflecting erythrocyte deformability, were within the normal range. We have studied the effects of a daily supplementation of 1.5 g omega-3 polyunsaturated fatty acids on blood viscosity in the CHD patients. After 6 weeks of treatment whole blood viscosity, at low and high shear rate, and plasma viscosity were significantly improved (all p less than 0.05), although not normalized. There was no effect of the fish oil on erythrocyte deformability.
Aged↗
Malnutrition and the heart: a microscopic analysis.
The effect of starvation on heart morphology was studied in the rat after total caloric deprivation. Morphometric analysis in subendocardial and subepicardial regions in the left and right ventricle was performed before and after starvation. A progressive fall in body weight was noted together with a biphasic change in ventricular weight. The ratio heart/body weight showed a continuous rise initially but stabilized at high levels in the later stage of starvation (p less than or equal to 0.005). The observed changes were analogous in the right and left ventricle. After starvation a significant increase in myocyte volume fraction was noted (p less than or equal to 0.01), but no regional differences were observed with respect to subendocardial-subepicardial and right-left ventricular zone comparison. The change in the non-myocyte fraction is situated in the vascular space and connective tissue. The volume fraction of non-capillary interstitial connective tissue, however, is significantly greater in the right ventricle than in the left (p less than or equal to 0.005). We conclude that in total starvation, after an initial rapid decline in heart weight, the heart is relatively spared. This leads to a rising heart/body weight ratio, until the later stage of malnutrition when the heart undergoes a hypotrophy to the same extent as other organs. This hypotrophy gives rise to a relative increase in myocyte volume fraction and a parallel decrease in capillary volume without major changes in the interstitial non-capillary connective tissue compartment.
Animals↗
Vitamin E status in a normal population: the influence of age.
Plasma vitamin E levels and age have been positively correlated up to the sixth decade of life. Since antioxidants protect biomembranes in vivo against oxidative damage, it has been hypothesized that free radical scavengers such as vitamin E may have protective effects against aging. In the present study, plasma vitamin E and lipids were determined in 95 healthy volunteers [mean age (+/- S.D.) 55.9 +/- 24.5 yr]. Special attention was focused on vitamin E status in the elderly: 23 individuals were older than 80 years. A significant age effect (p less than 0.005) was observed for both vitamin E and cholesterol, both being increased in the middle-aged group (40-59 yr) and decreased in the elderly (greater than or equal to 80 yr). Since a high plasma cholesterol represents a major risk factor for ischemic heart disease, decreasing levels of plasma cholesterol with advancing age in a healthy population-sample appears to be the result of negative selection. Plasma vitamin E concentration was correlated (p less than 0.001) with total cholesterol, triglyceride, and total lipid. Since vitamin E is mainly transported by plasma lipoproteins, these strong correlations suggest that changes in vitamin E should be considered as an epiphenomenon of altered plasma transport capacity. The determination of plasma vitamin E is therefore a poor indicator of the real tissue vitamin E activity.
Adult↗
Erythrocyte-sorbitol levels in non-diabetic patients during a 2-week period of total parenteral nutrition.
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Blood Glucose↗
Perioperative parenteral nutrition in the stressed diabetic patient.
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Diabetes Complications↗
Bacterial contamination of enteral diets.
Enteral feeding solutions can be contaminated by bacterial micro-organisms already present in the ingredients, or introduced during preparation or transport, or in the hospital ward. During jejunostomy feeding without pump or filter, ascending bacterial invasion of the feeding bag is possible. In patients with lowered immune response contaminated feedings can cause serious septic clinical problems. The progressive loss of the nutritional value of the enteral feeding solution by bacterial contamination has to be considered for all patients.
Enteral Nutrition↗
Vitamin E status in normocholesterolemic and hypercholesterolemic diabetic patients.
The close relationship between vitamin E, lipid and prostaglandin metabolism stresses the need for an accurate definition of the status of vitamin E in a diabetic population. Plasma vitamin E and plasma lipids were determined in 34 type I and 21 type II normocholesterolemic and in 7 hypercholesterolemic diabetics. They were also measured in 62 age- and sex-matched controls, 34 normocholesterolemic controls for type I, 21 normocholesterolemic controls for type II and 7 hypercholesterolemic individuals. Plasma vitamin E levels were not significantly different in type I and type II diabetics as compared to their respective control groups. Vitamin E levels were significantly increased (p less than 0.001) in hypercholesterolemic individuals, both in diabetics and in non-diabetics. The vitamin E/cholesterol ratio in these subjects was, however, not different from that of normocholesterolemic. Plasma vitamin E was correlated with plasma lipids, especially with total and LDL-cholesterol (p less than 0.001). Since vitamin E is mainly transported by plasma lipoproteins, these strong correlations suggest that changes in plasma vitamin E should be considered as an epiphenomenon of altered plasma transport capacity.
Adult↗
A prospective analysis of elective upper gastrointestinal endoscopy in the elderly.
The effectiveness of esophagogastroduodenoscopy in the elderly was evaluated in a prospective study of 656 consecutive patients undergoing endoscopic examination of the upper gastrointestinal tract. Forty-six percent of the patients were younger than 65 years, and 13% were in the age group above 79 years. Initial complaints and final endoscopic diagnosis were related to sex and age. Statistically significant age-related differences in outcome diagnosis were found for gastritis in younger men (p less than 0.01) and negative examinations in younger women (p less than 0.01). Duodenitis (p less than 0.05) and duodenal ulcer disease (p less than 0.05) occurred more frequently in men, whereas hiatal hernia was more frequent in women (p less than 0.05). Older people presented with a more nonspecific pattern of complaints and symptoms, but, nevertheless, a good correlation was observed between complaints and endoscopic abnormalities in the elderly compared with a younger group. Since esophagogastroduodenoscopy was well tolerated and did not provoke a higher incidence of complications in the elderly, it was concluded that endoscopic evaluation of the upper gastrointestinal tract is a safe and effective examination for the investigation of upper abdominal complaints in a geriatric patient population.
Age Factors↗
Vitamin E status in patients on parenteral nutrition receiving Intralipid.
Low vitamin E levels have been found to be a frequent side effect in patients on total parenteral nutrition (TPN). In the present study, the vitamin E content of fat emulsions (Intralipid) was measured and the influence of the intravenously administered lipid emulsion on plasma vitamin E levels was investigated. The majority of vitamin E was provided in the beta + gamma-tocopherol fractions (68.7% of total tocopherol). Vitamin E levels in patients were significantly lower (p less than 0.05) as compared to age- and sex-matched normal controls. Although sufficient amounts of vitamin E (16.9 +/- 0.8 IU daily) were infused, according to RDA requirements, E-plasma levels decreased even further during the course of TPN. It was concluded that high amounts of biologically less active tocopherol isomers are not sufficient to maintain vitamin E plasma levels. Supplemental sources of alpha-tocopherol are needed and more attention should be paid to the different tocopherol isomers in the quantitation of the daily allowances of vitamin E.
Adolescent↗
Respiratory insufficiency in acid maltase deficiency: the effect of high protein diet.
A 27-yr-old woman with the myopathic form of acid maltase deficiency (AMD) developed severe respiratory insufficiency after a crash diet resulting in a 6-kg weight loss. While being maintained on home ventilation, an hypercaloric high-protein, low-carbohydrate diet (1800-2000 cal; 28% carbohydrates, 55% fat, 17% protein with 1.7 g protein/kg body weight) was instituted. This ameliorated her condition up to a level where useful life was possible and ventilation could be diminished.
Adult↗
Morphometric changes in microvasculature in rat myocardium during malnutrition.
BACKGROUND: Because the interrelationship between the parenchymal cell population and the microvasculature is critical in normal organ function, the effects of starvation on rat myocardium were studied morphometrically with respect to the microvasculature. METHODS: Morphometric analytical studies were performed on myocardium of adult, female Wistar rats (groups of 5-7 rats) on fasting days 0, 1, 2, 4, 6, 8 and 10. Since cardiac muscle is a tissue with a high level of anisotropy, methods based on the concept of vertical planes were used to describe quantitative alterations in the rat myocardium both at the cellular and ultrastructural level. RESULTS: Morphometric analysis of electromicrographs of myocardium showed an increase in capillary density together with a decrease in capillary lumen cross-sectional area during starvation (p < .05). There was no significant change in volume fraction of the capillaries but surface density of the myocytes increased significantly (p < .01) and the diffusion distance for oxygen from the capillary lumen to the mitochondrion decreased (p < .01). CONCLUSIONS: Malnutrition alters the interrelationship between parenchyma and vascularization in the heart. This leads to a significant decrease of the diffusion distance for metabolites. This decrease of diffusion distance may improve cellular energy supply and offers a relative protection of the metabolism in the malnourished myocyte.
Animals↗