Effects of 2, 3, 7, 8-tetrachlorodibenzo p-dioxin (TODD) on hepatic, renal, lung, and serum vitamin A levels were investigated in species/strains, which show highly variable susceptibility to TCDD toxicity. Young male Hartley guinea pigs, Sprague-Dawley rats, C57Bl/6 mice, DBA/2 mice, and Golden Syrian hamsters received single intraperitoneal doses, in the range 0.5-400μg TCDD/kg body weight, aimed to produce a similar toxic and limited lethal effect in all species. Animals were sacrificed 1, 7, 14, 28, 56, and 112 days after TCDD injection. The time-related increase in hepatic vitamin A storage was inhibited by TCDD in all species studied, but the doses required to produce the inhibition were considerably varied due to species. The duration of the inhibition was dependent both on dose and species. All species, except for the guinea pig, managed to increase the liver reserves of vitamin A at the end of the study, as compared to the amount present at the time of TCDD treatment. A marked increase in renal vitamin A content, related to TCDD exposure, was observed in the rats, as opposed to a slight decrease in the guinea pigs and no effect in mice or hamsters. All species tested, except for the C57B1/6 mouse, showed a marked TCDD-related decrease in pulmonary vitamin A. The rat was the only species which showed a consistent effect (a small increase) in serum vitamin A levels, as a result of exposure to TCDD. The effects of TCDD on the hepatic and pulmonary vitamin A contents correlated reasonably well with the observed toxic response in this study. However, the correlation could not be observed for the effects of TCDD on renal, and serum vitamin A levels.

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This paper describes the synthesis and structural assignment of novel ¹²⁵I-l α, 25-dihydroxyvitamin D₃ derivatives (1a) and (lb) labeled with ¹²⁵I-Bolton-Hunter reagent [N-succinimidyl 3-(4-hydroxy-3-iodo [¹²⁵I] phenyl)propionate] (1), which is known as a protein-labeling reagent, as tracers for radioimmunoassay (RIA). The radiospecific activities of these tracers (1a) and (lb) were calculated as 2, 200 Ci/mmol (81.4TBq/mmol).

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We studied the effect of pyridoxal-5'-phosphate (PAL-P) on protein glycosylation and diabetic nephropathy in NSY mice. In experiment 1, an in vitro model of the browning phenomenon involving the incubation of lysine and glucose was inhibited by PAL-P. In experiment 2, administration of PAL-P to congenitally diabetic NSY mice markedly reduced the thickening of the glomerular basement membrane. These results suggest that PAL-P has the potential to be used for reducing the nephrotic complications of diabetes mellitus.

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In 781 female college students, there were 41 cases of iron deficiency anemia, 209 of latent iron deficiency, 3 of other anemias, and 528 normal cases. Fifty-four volunteers recruited from the iron deficiency anemia and severe latent iron deficiency groups were randomly divided into 4 study groups. Groups I and III received 500 mg of vitamin C daily, and groups II and IV received ferric ammonium citrate (FeAC; equivalent to 6mg iron) in addition to vitamin C for 9 weeks. Groups I and II were loaded by aerobic exercise at 50% V0₂ max. Significant differences between groups were noted in serum ferritin (SF) in III/IV, hematocrit (Ht) in II/III and III/IV, and reticulocytes (RET) in I/II, I/IV, and III/IV. Hemoglobin (Hb) and other iron-related blood indices tended to normalize in groups II and IV when compared with the pre-values. VO₂ max was elevated in groups I and II regardless of iron treatment, but was augmented more in group II than group I.

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0-β-D-Galactopyranosyl-(1→4)-O-β-D-galactopyranosyl(1→4)-D-glucopyranose (designated as 4'GL) are produced from lactose with Cryptococcus laurentii OKN-4. Excretion and metabolism of 4'GL in rats were examined using a radioisotope technique. [U-¹⁴C]4'GL was synthesized from [U-14C]lactose by Cryptococcus laurentii OKN-4. The 14`02 in expired air was counted after oral administration of [U-¹⁴C]4'GL or [U-¹⁴C]lactose in conventional rats, rats treated with antibiotics and germ-free rats. The rate of ¹⁴CO₂ excretion from conventional rats given [U-¹⁴C]4'GL was slower than that from those administered [U-¹⁴C]lactose. When [U-¹⁴C]4'GL was orally administered to rats given antibiotics, there was a 2-h delay in ¹⁴C0₂ excretion, as compared to conventional rats. In germ-free rats, total excretion of ¹⁴C0₂ from [U-¹⁴C]4'GL decreased to about one-third of that of conventional rats during a 24-h period. Radioactivities in the serum, liver, and carcass of the [U-¹⁴C]4'GL oral administration group were lower than those of the [U-¹⁴C]lactose oral administration group. Radioactivities in the feces and urine however, were higher in [U-¹⁴C]4'GL group than in [U-¹⁴C] lactose group.

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An animal model of marginal zinc deficiency was tested in mice, and salt taste threshold and salt preference were investigated in the state of marginal zinc deficiency. Two experiments were conducted. In Experiment 1, four-week-old male ICR mice were fed diets of three different levels of zinc content (3.17, 9.27, or. 48.13μg Zn/g) for 60 days. Food intake, growth, zinc levels in tissues, hepatic metallothionein (MT) content, and activities of selected enzymes (hepatic and RBC δ-amino-levulinic acid dehydratase (ALAD) and plasma alkaline phosphatase (ALP)) did not differ among the groups throughout the experiment, and no overt signs of zinc deficiency were manifested in any group. In Experiment 2, four-week-old male ICR mice were fed a zinc-deficient diet (1.98μg Zn/g) or a zinc-adequate diet (49.14μg Zn/g) for 56 days. Food intake and growth did not differ between the two groups, and no overt signs of zinc deficiency were observed throughout the experiment. Zinc levels in the plasma and femur-but not those in the brain, kidneys, liver, and red blood cell (RBC)-and plasma ALP activities were significantly lower on Day 42 and Day 56 of the experiment in the mice fed the zinc-deficient diet (ZnD group) than in those fed the zinc-adequate diet (ZnA group). Hepatic MT contents were lower in the ZnD group than in the ZnA group on Day 56 only. Salt taste threshold was 0.05% in the ZnA group, while it was 0.1% in the ZnD group, between Day 30 and Day 38, and between Day 44 and Day 52 of the experiment. Preference for 0.9% NaCl solution was no different in the two groups when tested between Day 38 and Day 40 or between Day 52 and Day 54, but that for 1.6% NaCl solution was significantly higher in the ZnD group than in the ZnA group between Day 40 and Day 42, and between Day 54 and Day 56.

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Both thiamine hydrochloride and thiamine tetrahydrofurfuryl disulfide were added separately to table wines at concentrations equivalent to 0.3 and 1.5μg of free thiamine per kJ of caloric energy. The resultant mean increments in thiamine activity, measured by Lactobacillus fermenti microbiological assay after 21 months of storage, were in the range 55 to 103% of the added vitamin, indicative of high bioavailability of thiamine from this source.

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The behavior of L-ascorbic acid (AsA) in the healing process of wounds in guinea pigs was investigated by determining AsA and dehydroascorbic acid (DAsA) levels. Dorsal skin wounds of guinea pigs fed AsA-deficient diets for 10 days were surgically induced, and the animals were intraperitoneally supplemented with 0, 0.5, 5, 50mg/day of AsA for 4 days, respectively. The animals were sacrificed, and the amounts of AsA and DAsA in healing skin wound and intact skin were determined by high-performance liquid chromatography (HPLC). It was found that total AsA levels in the healing wound of the animals in AsA-supplemented groups were almost similar to those in intact skin, respectively. However, DAsA levels in the healing wounds on day 4 of the healing period are significantly higher than those not only in the intact skin but also in the completely regenerated skin on day 14 of the healing period. From these results, it was suggested that the wound healing process was accompanied by the oxidation of AsA, moreover, the reduction of DAsA to AsA did not sufficiently occur in vivo.

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