Thesis (Ph.D.)--Virginia Commonwealth University, 2009. / Prepared for: Dept. of Medicinal Chemistry. Title from title-page of electronic thesis. Bibliography: leaves 77-92.

Diss. (sammanfattning) Stockholm : Karol. inst., 2003. / Härtill 5 uppsatser.

Vitamin B-6 status was examined in a group of 46 elderly subjects who were selected from nursing home residents, hospital patients, and free living individuals in Denton County. Subjects were limited to men and women over 60 years of age. Erythrocyte aspartate aminotransferase stimulation with pyridoxal phosphate (in-vitro) was studied as the biochemical criterion of vitamin B-6 status. The pyridoxine status of these 46 subjects (the reference group) was measured in order to be able to identify people with a relatively poor B-6 status. A sub-group of the reference group was composed of 4 subjects who took B-6 supplements (supplemented group). There was no significant difference (0.05 level) in the basal activity, stimulated activity, percentage stimulation, or body weight, after treatment with 10 mg pyridoxine hydrochloride for 4 weeks, even though all 4 subjects had an improved B-6 status (based on percentage stimulation) after taking the supplement. The data indicated that of the 4 subjects tested, 2 showed a large change in the basal activity, stimulated activity, and percentage stimulation. The lack of significant difference (0.05 level) was probably due to a small sample size. One subject reported an increased appetite and body weight after treatment with pyridoxine.

Recently maternal intake of multivitamins has been associated with a reduced risk of orofacial clefts (OFC)in human epidemiologic studies. In the Philippines, vitamin B-6 deficiency was found to be associated with increased risk of OFCs. The birth prevalence of OFCs in the Philippines is among the highest known, but Filipino emigrants in the United States have lower rates, indicating that environmental factors may play an important role in causing OFCs in the Philippines. The prevalence and possible causes of vitamin B-6 deficiency were investigated through dietary and biochemical assessments in case-control study in Negros Occidental, Philippines. Mothers with OFC offspring (cases) were ascertained during a 2-week OFC surgical mission of Operation Smile in 1997, and mothers without OFC offspring (controls) were recruited at randomly selected neighborhood health centers. Sixty-three percent case-mothers and 41 percent control-mothers were vitamin B-6-deficient. Dietary vitamin B-6 intake was low in both cases and controls but lower in cases. Case-mothers consumed 9.4 percent fewer calories than the control-mothers. Rice was the major contribution of total energy, carbohydrate, and protein for both cases and controls. Both cases and controls consumed fruits, seafood, dairy, fats, and oils with similar frequency, but cases consumed grains and grain products, vegetables, meats, beans and bean products, and roots less frequently. The vitamin B-6 activity coefficient, an indicator of vitamin B-6 deficiency, was correlated positively with plasma homocystine and negatively with plasma and red cell folate in cases only. No significant correlations were found between vitamin B-6 status and maternal age, smoking, or drinking, in either cases or controls. Vitamin B-6 deficiency appears to be an important yet complex problem in Negros Occidental because it is widespread and strongly associated with the risk of OFC birth defects. This condition may be a consequence of 1) high polished rice consumption, 2) low vitamin B-6 intake from other food sources, 3) presence of glycosylated vitamin B-6 in plant foods, 4) high vitamin C-induced vitamin B-6 hydroxylation, or 5) a potential zinc deficiency.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2006. / Härtill 5 uppsatser.