THE JEJUNAL MUCOSA IN PATIENTS WITH NUTRITIONAL FOLATE DEFICIENCY AND MEGALOBLASTIC ANEMIA

Long-lived ames dwarf mice are resistant to chemical stressors

To probe the connection between longevity and stress resistance, we compared the sensitivity of Ames long-lived dwarf mice and control littermates with paraquat, diquat, and dobutamine. In young adult animals, 95% of male and 39% of female controls died after paraquat administration, but no dwarf animals died. When the experiment was repeated at an older age or a higher dosage of paraquat, dwarf mice still showed greater resistance. Dwarf mice also were more resistant to diquat; 80% of male and 60% of female controls died compared with 40% and 20% of dwarf mice, despite greater sensitivity of dwarf liver to diquat. Dwarf mice were also less sensitive to dobutamine-induced cardiac stress and had lower levels of liver and lung F(2)-isoprostanes. This is the first direct in vivo evidence that long-lived Ames dwarf mice have enhanced resistance to chemical insult, particularly oxidative stressors.

Morphologic changes in the small intestine after chronic alcohol consumption

The morphology of the small-intestinal mucosa was studied in 11 alcoholic patients admitted to hospital for detoxification. A first biopsy specimen from the small intestine was taken as soon as possible after admission and a second specimen after about 6 weeks of abstinence. The specimens were studied in the light microscope, in the scanning electron microscope, and by immunohistochemistry. Morphometrically, a slight reduction in villus height in relation to crypt depth was observed. One patient had a subtotal villus atrophy. After abstinence the villus height was increased in five of the six patients who accepted a second biopsy. No obvious changes were seen in the frequency and appearance of peptidergic nerves or endocrine cells. Ultrastructurally, pronounced alterations were seen in the surface ultrastructure of the enterocytes. In two specimens bacterial adhesion to the mucosal surface was also found. The ultrastructural changes were unaltered after abstinence. In serum the concentrations of zinc were reduced, and the levels of copper were elevated compared with a group of teetotallers. A recently developed marker of high alcohol consumption, carbohydrate-deficient transferrin, was as good an indicator as the other conventional biochemical markers.

Nutrition in the alcoholic

Effective management of nutritional problems in the alcoholic patient requires that the clinician understand the complex interaction of alcohol and nutrition. Nutritional deficiencies should be prevented and, if present, corrected. However, experimental, clinical, and epidemiological evidence indicates that despite adequate diets, ethanol has direct toxic effects on the digestion, absorption and activation of foodstuff. Furthermore, recent studies have shown that even in well nourished populations relatively small amounts of alcohol may have cirrhogenic potential. For these reasons, the overall approach to the management of the alcoholic must involve the control of alcohol intake as well as the prevention and correction of nutritional disturbances.

Structural and functional abnormalities of the small intestine due to nutritional folic acid deficiency in infancy

Structural abnormalities and disaccharidase deficiency were demonstrated in biopsies of duodenal mucosa from four infants who had symptoms of failure to thrive and chronic diarrhea associated with a megaloblastic anemia. Goat's milk was the main dietary constituent for each infant for six to eight months prior to presentation. The structural abnormalities consisted of villous blunting, crypt hypertrophy, megaloblastic changes in epithelial cells, and nuclear enlargement. All changes reverted to normal with the addition of folic acid to the diet. This study provides evidence that nutritional folic acid deficiency can cause structural and functional alterations of the small intestine in infants.

Partial villous atrophy in nutritional megaloblastic anaemia corrected by folic acid therapy

A patient with megaloblastic anaemia due to nutritional folate deficiency is described. Partial villous atrophy and malabsorption of xylose showed progressive improvement to normal with folic acid therapy.