Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042875 (vitamin E deficiency)
 916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acanthocytic red cells in patients with abetalipoproteinemia are morphologically similar to the red cells in spur cell anemia. Fluidity of membrane lipids is decreased in spur cells due to their excess cholesterol content. Acanthocyte membranes have an increased content of sphingomyelin and a decreased content of lecithin. To assess the effect of this abnormality of acanthocyte membrane lipid composition on membrane fluidity, we studied red cells from five patients with abetalipoproteinemia and four obligate heterozygote family members. Membrane fluidity was measured in terms of microviscosity ( eta) at 37 degrees C, assessed by means of the fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene. It was increased from 3.2+/-0.1 poise in normals to 4.01-4.14 poise in acanthocytes. This was associated with an increase in the sphingomyelin/lecithin ratio from 0.84+/-0.08 in normals in 1.45-1.61 in acanthocytes. The eta of acanthocyte membranes was not influenced by the degree of vitamin E deficiency. Similar changes in eta were observed in liposomes prepared from red cell lipids. Heterozygotes had normal sphingomyelin/lecithin ratios and normal values for eta. The flow activation energy for viscosity, a measure of the degree of order in the hydrophobic portion of the membrane, was decreased from 8.3 kcal/mole in normal red cells to 7.2 kcal/mole in acanthocytes, indicating that acanthocyte membrane lipids are more ordered. Variations in the sphingomyelin/lecithin mole ratio of liposomes prepared from brain sphingomyelin and egg lecithin with equimolar cholesterol caused similar changes in both eta and activation energy. The deformability of acanthocytes, assessed by means of filtration through 3-mum filters, was decreased. These studies indicate that the increased sphingomyelin/lecithin ratio of acanthocytes is responsible for their decreased membrane fluidity. As in spur cells and in red cells enriched with cholesterol in vitro, this decrease in membrane fluidity occurs coincidentally with an abnormality in cell contour and an impairment in cell deformability.
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PMID:Decreased fluidity of red cell membrane lipids in abetalipoproteinemia. 87 76

A 16-month-old infant with hepatic fibrosis, cholestasis, and chronic jaundice had signs of vitamin E deficiency, including mild acanthocytosis, thrombocytosis, increased peroxide haemolysis, and absent serum vitamin E. Abormal prothrombin consumption and platelet restocetin aggregation suggested the presence of defective platelet function, and correction studies indicated that this was due to a plasma defect. The abnormality was corrected by treatment with vitamin E, and the findings suggest a possible role of this vitamin in platelet reactions.
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PMID:Vitamin E deficiency and platelet functional defect in a jaundiced infant. 117 3

Pathological examination was carried out of the skeletal muscle of an 8-year-old boy with abetalipoproteinemia. The patient complained of diarrhea, and showed a deficiency of betalipoprotein, decreased fat-soluble vitamins, acanthocytosis and a mild increase in serum creatine kinase. The prominent histochemical finding was punctate deposits of acid phosphatase activity in most fibers. Ultrastructural lesions revealed a number of giant lysosomes. Although these pathological findings seemed to be related to vitamin E deficiency, other pathological findings such as concentric laminated bodies or filamentous bodies were also observed. The clinical course and the changes in the pathological findings in our patient after long-term vitamin E therapy need to be observed.
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PMID:Histochemical and ultrastructural pathology of skeletal muscle in a patient with abetalipoproteinemia. 831 Aug 5

Acanthocytosis occurs because of ultrastructural abnormalities of the erythrocyte membranous skeleton resulting in reduced membrane fluidity. At least three hereditary neurological conditions are associated with it, although as yet the pathogenesis of the neurological features is unknown. In abetalipoproteinaemia, an autosomal recessive condition, vitamin E deficiency results in a progressive spinocerebellar syndrome associated with peripheral neuropathy and retinitis pigmentosa. Neuroacanthocytosis is also probably an autosomal recessive condition and is characterised by chorea, orofaciolingual dyskinesia, dysarthria, areflexia, seizures and dementia. McLeod syndrome is an X-linked recessive disorder usually presenting in males as a benign myopathy with areflexia, in association with a particular abnormality of expression of Kell blood group antigens. However, occasionally the neurological features are more severe and indistinguishable from those of neuroacanthocytosis. Recent advances in molecular genetics may assist better understanding of the disease mechanisms and the search for more effective treatments.
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PMID:Acanthocytosis and neurological disorders. 1128 40

Abetalipoproteinemia is a rare metabolic disorder that causes disturbed lipid absorption with consequent hypocholesterolaemia and liposoluble avitaminosis. The broad spectrum of presentations includes malabsorption, failure to thrive and acanthocytosis in children, while later in life expected manifestations include coagulopathy, myopathy, retinitis pigmentosa, peripheral neuropathy, hyporeflexia and ataxia. These neurological complications stem from demyelination secondary to vitamin E deficiency. Another complication is reduced fertility in women. In the event of a successful conception, issues arise in vitamin supplementation, the mainstay of treatment of abetalipoproteinemia. The skilful clinician must master the delicate balance between the teratogenic effects on the fetus of over as well as under replacement of vitamins, pregnancy complications such as premature rupture of membranes and eclampsia, and, finally, maternal complications such as corneal ulcers. We describe the management of a patient ranging from pubertal growth to bearing a successful spontaneous pregnancy with an outcome of a completely healthy mother and child.
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PMID:A successful spontaneous pregnancy in abetalipoproteinemia: Amsterdam or the art of vitamin replacement? 2548 86