Folic acid (folate) levels were measured in the serum of patients with various neurological diseases in Japan. Thirty-six patients showed decreased serum folate levels among 343 consecutive neurological patients (10.5%). Folate administration (15 mg/d) to folate-deficient patients improved neurological symptoms in 24 of 36 cases (67%). Serum folate levels were significantly lower in female than in male folate-deficient patients. Folate-deficient patients showed predominantly axonal neuropathy, which responded to folate sup-plementation more markedly. Male patients more frequently exhibited neuropathy, espe-cially demyelinating and motor-dominant neuropathy, than females. Anemia was corre-lated with male sex and low serum folate levels. Male patients were more responsive than fe-males to folate treatment. More male patients had taken excess alcohol or received gastrec-tomies than females. Neurological symptoms were more frequently improved by folate sup-plementation in patients with neuropathy than exclusive encephalopathy. Serum folate lev-els were lower in patients with encephalopathy, especially those with dementia, while folate therapy was more effective in neurological patients without dementia. Dysgeusia and ane-mia improved in all patients after folate administration. Neurological patients with malab-sorption or treated with continuous drip infusion were resistant to folate therapy. Since fo-late-responsive neuroencepahlopathies are not rare among patients with neurological dis-eases in Japan, the serum folate level would serve as a valuable indicator for folate supple-ment therapy.

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The effect of vitamin B₆-deficiency on the B₆-vitam.er concentrations, level of S-adenosylhomocysteine (SAH) and S-adenosylmethionine (SAM) were studied in rat tis-sues. The plasma pyridoxal 5'-phosphate (PLP) and, pyridoxal (PL) levels were lower in the B₆-deficient group compared to the control group. After 5 weeks of feeding the experimental diets, tissue PLP, pyridoxamine 5'-phosphate (PMP) and PL concentrations were signifi-cantly lower in the B₆-deficient group compared to the control and the pair-fed control groups. Thymus PLP and PL levels were lower in the B₆-deficient group. The concentration of SAM in the B₆-deficient group decreased to approximately 50% and 25% in liver and thy-mus, respectively. However SAH concentration was 3.5 and 2 fold higher compared to the control and the pair-fed control groups. Thus, the ratio of SAM/SAH was significantly de-creased in the B₆-deficient group compared to the control or the pair fed-control group. In addition, the S-adenosylhomocysteine hydrolase (EC 3.3.1.1) activity increased by 45% and 15% in liver and thymus, respectively, in the B₆-deficient group compared to the pair-fed control and the control groups. However, the activity of L-methionine S-adenosyltransferase (EC 2.5.1.6) was also unaffected. Concentrations of SAH and SAM, SAM/SAH ratio and ac-tivities of S-adenosylhomocysteine hydrolase and L-methionine S-adenosyltrasferase in rat brain were not affected by the B₆-deficiency. We infer that the alteration of B₆ metabolism, especially the reduction of PLP contents in liver and thymus, caused by the B₆ deficiency, re-sulted in accumulation of SAH as well as reduction of SAM and the SAM/SAH ratio. The re-duction of the SAM/SAH ratio was due to a block in the catabolism of methionine via the traps-sulfuration pathway. These may lead to inhibition of transmethylation reaction of DNA, RNA and protein, the synthesis and function of thymic lymphocyte and result in dam-age to tissues.

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This study investigated changes in Ca balance and BMD during pregnancy in female rats. During pregnancy, the intestinal Ca absorption increased significantly, and Ca accumulation was also markedly elevated. However, BMD values for the lumbar spine de-creased significantly during pregnancy. Twenty female SD rats, 10 weeks of age (Japan SLC Co., Shizuoka, Japan) were acclimated for 2 weeks. Then, the rats were divided into two groups; the control (no pregnancy) group (n=10) and the pregnant group (n=10). The rats in the pregnant group were kept in a cage with a male rat for 5 days at 12 weeks of age, and all 10 were successfully impregnated. During the pregnancy period, the values for intestinal Ca absorption and the rate of the intestinal Ca absorption in the pregnant group were signif-icantly greater than those of the control group. In addition, in spite of the significant in-crease in urinary Ca excretion in the pregnant group, the Ca accumulation was markedly elevated during the latter half of pregnancy. On the other hand, the BMD value in the lum-bar spine for the pregnant group significantly decreased during pregnancy. These findings suggest that pregnancy accelerated intestinal Ca absorption and Ca accumulation in female rats, while the lumbar spine BMD decreased during pregnancy.

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There are an overwhelming number of reports indicating the beneficial effects of fish oil supplements in human and animal nutrition. The purpose of this study, second in a series, was to evaluate the effects, particularly those that may be harmful, of high-dose, long-term consumption of fish oil concentrates (FOC) using male and female rats. One hun-dred and twenty male and 120 female rats were gavaged daily with oils and oil mixtures in a volume equal to 0.5% body weight (5 mL/kg/d) for 13 weeks. The administered oils were corn oil, pure menhaden oil (MO), pure MaxEPAR fish oil or different mixtures of corn oil with MO. The stability and the homogeneity of the dosing solutions were tested under study conditions. The animals received isocaloric and isonitrogenous diets throughout. Food and pure water were supplied ad libitum. At the end of the in-life phase of the study, the animals were anaesthetized with CO₂ and humanely killed by exsanguination. Blood and other tis-sues were prepared for various clinical, histopathological and laboratory tests. Some benefi-cial effects of FOC, such as reduction in total serum cholesterol, in rats were confirmed. However, we also observed a significant reduction in absolute amount of serum HDL and a significant increase in relative liver and spleen weights in both sexes with the high dose of FOC. High doses of FOC (5 mL/kg/d) reduced serum iron and vitamin E concentrations. A reduction in osmotic fragility of RBC as well as an increase in RBC deformity were also ob-served in rats treated with high doses of FOC. These rats showed a significant overall in-crease in WBC count. We conclude that in rats, subchronic consumption of high levels of FOC can be beneficial but may also be harmful because of induction of clinical abnormalities including increased red cell deformity, increased relative liver and spleen weights, and re-duced serum HDL, iron and vitamin E concentrations.

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Effects of tomato juice supplementation on the carotenoid concentration in lipoprotein fractions and the oxidative susceptibility of LDL were investigated in 31 healthy Japanese female students. These subjects were randomized to one of three treatment groups; Control, Low and High. The Control, Low and High groups consumed 480 g of a control drink, 160 g of tomato juice plus 320 g of the control drink, and 480 g of tomato juice, providing 0, 15 and 45 mg of lycopene, respectively, for one menstrual cycle. The in-gestion of tomato juice, rich in lycopene but having little β-carotene, increased both ly-copene and β-carotene. Sixty-nine percent of lycopene in plasma was distributed in the LDL fraction and 24% in the HDL fraction. In the Low group, the lycopene concentration in-creased 160% each in the VLDL+IDL, LDL and HDL fractions (p<0.01). In the High group, the lycopene concentration increased 270% each in the VLDL+IDL and LDL fractions, and 330% in the HDL fraction (p<0.01). β-Carotene also increased 120% and 180% in LDL fractions of the Low and the High groups, respectively. Despite these carotenoid increases in LDL, the lag time before oxidation was not prolonged as compared with that of the Control group. The propagation rate decreased significantly after consumption in the High group. Multiple regression analysis showed a positive correlation between lag time changes and changes in the α-tocopherol concentration per triglyceride in LDL, and a negative correla-tion between propagation rate changes and changes in the lycopene concentration per phospholipid in LDL. These data suggest that α-tocopherol is a major determinant in pro-tecting LDL from oxidation, while lycopene from tomato juice supplementaion may con-tribute to protect phospholipid in LDL from oxidation. Thus, oral intake of lycopene might be beneficial for ameliorating atherosclerosis.

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The aim of the present study is to investigate the validity of a new method to estimate the food intake of individual subjects by a household-based dietary survey. The new method is based on the combination of household-based food weighing and approxi-mating the proportions by which family members shared each dish or food in the house-hold, which has been one of the components of the National Nutrition Survey, Japan, since 1995. We analyzed two sets of data from 64 volunteers (female students taking a dietitian course and their mothers) in 32 households by the approximated proportion method (method A) and the individual-based food weighing method (B) as a reference measurement. Energy and macronutrient intake by individual subjects estimated by method A was highly correlated to the corresponding values by method B (Pearson's correlation coefficients; r=0.90-0, 92). Average energy intake was likely to be underestimated by method A com-pared with method B, being lower by 94 kcal (6.2% of the reference value in method B), at least in the young and middle-aged female adults that were the subjects of this study when intake of boiled rice was separately analyzed, underestimation of energy intake by method A was 44 kcal, which contributed to approximately 50% of the total magnitude of the under-estimation. The procedure manual for the National Nutrition Survey requests the partici-pants to individually weigh the amount of boiled rice taken by family members in the house-hold. However, this procedure is not observed in many actual settings. Therefore, following this procedure would be an effective measure to improve the accuracy of the dietary data.

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We have developed a method to quantitate hepatic apolipoprotein (apo) B, LDL receptor, 3-hyddroxy-3-methylglutary coenzyme A reductase (HMG-CoA reductase) and cholesterol 7α-hydroxylase mRNA expression in rats fed a cholesterol-enriched diet after long-term feeding using competitive RT-RCR. Rats (8 wk of age) fed a conventional diet were shifted to diets containing 10% perilla oil (PEO, oleic acid+linoleic acid+α-linolenic acid), borage oil (BRO, oleic acid+linoleic acid+γ-linolenic acid), evening primrose oil (EPO, linoleic acid+γ-linolenic acid), mixed oil (MIO, oleic acid+linoleic acid+γ-linolenic acid+α-linolenic acid), or palm oil (PLO, palmitic acid+oleic acid+linoleic acid) With 0.5% cholesterol for 15 wk. There were no significant differences in the food intake and body weight gain among the groups. The liver weight in the PEO and PLO groups was significantly higher than other groups. The serum total cholesterol and very low density lipoprotein (VLDL)+intermediate density lipoprotein (IDL)+low density lipoprotein (LDL)-cholesterol concentrations were consistently higher in PLO group than in the other groups. The serum high density lipoprotein cholesterol concentration was significantly lower in the PEO group than in the other groups. The liver cholesterol concentration group was significantly higher in the PEO than in the other groups. There were no significant differences in the hepatic LDL receptor mRNA level among the groups. Hepatic apo B, HMG-CoA reductase and cholesterol 7α-hydroxylase mRNA levels were not affected by the experimental conditions. However, hepatic cholesterol 7α-hydroxylase mRNA level in the PEO and MIO groups tended to be higher than in the other groups. The fecal cholesterol extraction was significantly higher in the MIO and PLO groups than in the PEO and EPO groups and the total bile acid extraction was significantly higher in the PEO and MIO groups than in the PLO group. The results of this study demonstrated that both n-6 fatty acid and n-3 fatty acids such as γ-linolenic acid and α-linolenic acid lowered serum total cholesterol and VLDL+IDL+LDL-cholesterol concentrations of rats in the presence of excess cholesterol in the diet compared with dietary saturated fatty acid.

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Long-term enteral feeding by tube has become a frequently used procedure in elderly patients. However, only a few studies dealing with the nutritional assessment of such patients are currently available. This study was designed to clarify this issue. Anthropometric and biochemical variables, energy expenditure and dietary intake were in-vestigated in 44 hospitalized bed-ridden patients with and without tube feeding over 65 years of age and 41 age-matched free-eating elders in a nursing home. All patients with tube feeding received enteral nutrition by nasogastric tube. The body weight, body mass index, mid-upper-arm circumference, arm muscle circumference and serum level of albu-min were significantly lower in the patients with and without tube feeding, compared with free-eating elders of both genders (p<0.05). Energy intakes of the patients with tube feeding were 1, 171±286 kcal/d (about 26 kcal/kg/d), which is comparable to the predicted total energy expenditure (1.2× basal energy expenditure). Protein intake was 44.9±13.1 g/d (about 1.0 g/kg/d) and the percentage of protein per total energy was 15%. These intakes are generally considered to be optimal for bed-ridden patients receiving tube feeding. However, the incidence of protein-malnutrition, as evidenced by decreased arm muscle cir-cumference (<80% of normal) and hypoalbuminemia (<35 g/L), in the patients with tube feeding was significantly higher than that in the healthy elders. In addition, the orally fed bed-ridden patients were also malnourished, suggesting that the bed-ridden patients easily became malnourished even if they were fed energy and protein which approximated calcu-lated predicted values. These findings raise a problem concerning nutritional management of bed-ridden patients.

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Eicosapentaenoic and docosahexaenoic acids were distributed mainly in the sn-1 and 3 positions of seal oil triacylglycerols and in the sn-2 position of fish oil triacylglyc-erols. Seal oil-rich or fish oil-rich fats having constant polyunsaturated (PUFAs)/monoun-saturated/saturated fatty acids and n-6/n-3 PUFAs ratios were fed to hamsters for 3 weeks. The control fat contained linoleic acid as the sole PUFA. The concentration of triacylglyc-erols in the liver was significantly lower in the fish oil group than in the control group. Phospholipid concentration in serum was lower and that in the liver was higher in the seal oil group compared with the fish oil group. The activities of fatty acid synthase (FAS), glu-cose-6-phosphate dehydrogenase (G6PDH), and the malic enzyme were significantly lower in both the fish and seal oil groups than in the control group. Dietary seal oil more effec-tively reduced arachidonic acid content in liver phosphatidylcholine and phos-phatidylethanolamine and serum phosphatidylcholine than fish oil. These results showed that different intramolecular distribution of n-3 PUFAs influenced glycerolipid metabolism and arachidonic acid content in serum and liver phospholipids of hamsters.

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For determination of selenium (Se) in biological materials, an improved method based on high performance liquid chromatographic determination of the fluo-rophore formed by reaction of selenite with 2, 3-diaminonapththalene was developed. The concentration detection limits were 0.5 ng/g in dried materials and 0.03 ng/mL in fluid ma-terials. In quadruplicate assays of 11 biological reference materials using the proposed method, measured Se concentrations were not significantly different from their certified val-ues, Thus, the proposed method is reliable and suitable for the determination of trace levels of Se in foods. Using the proposed method, Se concentrations in various kinds of tea were de-termined to assess the contribution of tea to daily Se intake in the Japanese population. Se concentration in the leaves of general black, green and oolong tea obtained in local retail stores was 33±19 ng/g (n=40). The leaves of a particular Chinese green tea sold under the name “high Se tea” were found to contain 455±184 ng/g (n=14) of Se. While the percent-age of Se extractable by infusion was less than 5% for the general teas, that in the high Se tea was more than 20%. These results indicated that intake of tea does not contribute to daily Se intake in the Japanese population. However, since infusions from high Se tea con-tained over 5 ng/mL of Se, consumption of over 1 L/d of tea derived from such high Se teas may increase the daily Se intake by close to 10%.

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We investigated dietary effects of cabbage fermentation extract (CFE) and young barley leaf powder (YBLP) on rat immune functions. Male Sprague-Dawley rats of 4 wk age were fed for 3 wk diets containing these samples at 0.1 or 1% level. After the feed-ing period, serum IgG level was significantly higher in the rats fed 1% CFE. IgG productivity of spleen lymphocytes was enhanced dose-dependently in both groups of CFE and YBLP. Furthermore, IgG productivity of mesenteric lymph node (MLN) lymphocytes was approxi-mately 2 times higher in the rats fed 1% CFE diet than in the control ones. IgA productivity of MLN lymphocytes tended to increase in both of CFE and YBLP groups. From these results, it was suggested that dietary CFE and YBLP reinforced Ig productivity in both systemic and intestinal immune systems. Moreover, CFE feeding tended to enhance the production of TNF-α by spleen lymphocytes. In spleen phospholipids, the level of arachidonic acid, a sub-strate for inflammatory lipid mediators, was not affected by CFE or YBLP feeding.

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L-Gulono-1, 4-lactone oxidase activity was detected in G. frondosa; therefore its properties were studied after purification. A 766-fold purified preparation of the enzyme from fresh fruit bodies was obtained by means of a seven-step procedure, the overall yield being 14%. The purified enzyme gave a single band on polyacrylamide gel electrophoresis and its absorption spectrum exhibited the characteristic of a flavoenzyme. The enzyme pro-duced L-ascorbic acid and H₂O₂, with L-gulono-l, 4-lactone (GL) as the substrate and oxygen as the electron acceptor, and was optimally active at around pH 7.0 and 45°C. Its molecular mass was determined to be 250 kDa on gel filtration, while the dissociated enzyme exhibited a molecular mass of 69 kDa on SDS-polyacrylamide gel electrophoresis, but the true molec-ular weight is unknown because of the trypsin treatment in the purification process. The apparent Km value for GL was 24±1 mi. Its substrate specificity was extremely high and, assuming that for GL to be 100, the following results were obtained, D-mannono-, 25: D-glu-cono-, 4; L-idono-, 3; L-galactono-l, 4-lactone, 2; and 15 other lactones tested, 0. It is pre-sumed that this enzyme is similar to animal GL-oxidase, ascomycetes D-arabinonolactone oxidase, etc.

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We reported that the growth promoting activity of di-n-butylphthalate (DBP) was observed when rats were fed with a niacin-free and tryptophan-limiting diet (Shibata et al., 1982. J Nutr Sci Vitaminol 28, 173-177). The present experiment was performed to in-vestigate whether this phenomenon is attributable to the increase in the conversion ratio of tryptophan to niacin. The weaning rats were fed with a 10% (low protein diet) or 20% pro-tein (conventional protein diet) diet with or without adding 1% DBP. The conversion ratio of tryptophan to niacin was significantly higher in the DBP group than in the control group; for 10% casein diets, it increased two-fold and for 20% casein diet, about five-fold. From these results, the previous finding is possibly explained by DBP increasing the conversion ratio of tryptophan to niacin.

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Effect of triacylglycerols containing medium- and long-chain fatty acids (TML) on body fat accumulation was studied in rats. Male Wistar rats were fed an experi-mental diet containing 25% soybean oil or TML for 6 weeks. The food intake for 6 weeks did not significantly differ between the two diet groups. However, the perirenal and mesenteric adipose tissue weight and carcass fat content were significantly lower in the TML diet group than in the soybean oil diet group. The epididymal adipose tissue weight and liver triacyl-glycerol content did not significantly differ between the two diet groups. The digestibility of dietary fat did not significantly differ between the two diet groups. These results suggest that an intake of TML decreases body fat accumulation compared to an intake of soybean oil in rats.

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The antibacterial activity of compounds obtained from licorice was measured against upper airway respiratory tract bacteria such as Streptococcus pyogenes, Kaemophilus irnfluenzae and Moraxella catarrhalis, Among the tested compounds, licoricidin exhibited the highest activity against all tested microorganisms with an MIC of 12.5, μg/mL. Three coumarin derivatives, glycyrol, glycyrin and glycycoumarin also showed antibacterial activ-ity.

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