• Biomedical Science Letters
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• v.12 no.1
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• pp.23-27
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• 2006

The rate of metallothionein synthesis on cadmium-poisoned rats reflects the level of toxicity, and also it reduces the toxicity which is caused by the uptake of cadmium. Chlorella supplementation in the diets of the cadmium-poisoned rats decreased the concentration of cadmium in blood and urine compared with the control group. Although the liver and kidneys of rats are major target organs of cadmium and coherence of metallothionein and cadmium, no previous study has determined the correlation between the rate of metallothionein synthesis in the liver and kidneys of rats and dietary supplementation of chlorella with cadmium uptake. This study analyzed total metallothionein level on the tissue of the liver and kidneys, the concentration of cadmium bound to the metallothionein, and the total concentration of cadmium on the tissue of the liver and kidneys after dietary supplementation with 1%, 5%, and 10% dried chlorella and 40 ppm of cadmium to 46 male SD rats (mean weight: $150\pm20\;g$) for 4 weeks. According to the data analysis of the total rate of metallothionein synthesis in the liver and kidneys, the group of SD rats on the supplementation with 1% chlorella and 40 ppm of cadmium showed a rate of $93.2\pm8.9\;ng/g$, a significant decrease of 58.8% compared to that of the control group of SD rats on the supplementation with cadmium only, which showed a rate of $227.3\pm32.5 ng/g$ (P=0.0001). In contrast, no significant difference was observed through the changing of chlorella concentrations between 5% and 10% chlorella supplementation with cadmium. The group supplemented with 1% or greater chlorella levels represented a greater decrease in the total cadmium concentration of the kidney and liver tissues, the amount of total metallothionein synthesis, the amount of metallothionein with binding to cadmium, and the concentration of free cadmium without binding to metallothionein. Consequently, the supplementation of 1% and 5% chlorella was effective in reducing the synthesis of metallothionein for cadmium uptake, but increased the rate of binding of cadmium to metallothionein.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.702-710
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• 2000

A large portion of total energy expenditure associated with ruminant livestock production goes towards maintenance. Approximately 55% of whole body energy use is consumed by visceral tissues (including internal organs) with the majority of this going to the liver and gastrointestinal tract. Muscle and adipose tissues consume about 27% of total body energy expenditure. Metabolic components within the viscera responsible for the majority of energy consumption include ion transport, protein turnover, substrate cycling, and urea synthesis (liver). Within muscle tissue of growing animals ion transport and protein turnover account for most of the energy expenditure. Protein synthesis consumes approximately 23% of whole body energy use and visceral tissues account for proportionally more of whole body protein synthesis than skeletal muscle. Research efforts focused on improving energetic efficiency of the tissues and metabolic mechanisms responsible for the majority of whole animal energy expenditure should provide information leading to more efficient production of an edible product.

• YAKHAK HOEJI
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• v.35 no.6
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• pp.530-554
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• 1991

The synthetic methodologies for the preparation of C-nucleosides are divided into four categories, and each category is discussed in details. The chemical rections which lead to other C-nucleosides from preformed the natural product pseudouridine are described first, followed by synthesis of C-nucleosides by condensation of pre-formed heterocyclic base with sugar, and by construction of heterocyclic base from a carbohydrate intermediate that bear functional carbon fragment at the anomeric position. Finally, methods of total synthesis of C-nucleosides from carbohydrate and achiral starting materials are presented.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2959-2961
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• 2009

Total synthesis of (${\pm}$)-licochalcone E (1), an allyl retrochalcone isolated from roots of Glycyrrhiza inflata, has been achieved from 4-tetrahydropyranyloxyacetophenone (7) with (E)-2-methoxy-4-(2-methyl-2-butenyloxy)benzaldehyde (6) or (Z)-2-methoxy-4-(2-methyl-2-butenyloxy)-benzaldehyde (11) through a convergent strategy involving aldol condensation and Claisen rearrangement as key steps.

• Toxicological Research
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• v.9 no.1
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• pp.45-60
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• 1993

The present study was carried out to evaluate the cytotoxicity of cadmium on cultured rat fibroblasts. The colorimetric assays of neutral red and tetrazolium MTT, the lactatedehydrogenase activity, the amounts of total protein, the rate of DNA synthesis, the amounts of unscheduled DNA synthesis, the frequency of sister chromatid exchange, the releasing rate of intracellular calcium, and light and electron microscopic studies were performed on cultured rat fibroblasts maintained in the media containing various concentrations of cadmium. The results were as follows: The neutral red(NR) and MTT values were decreased dose-dependently by cadmium, and the NR90, NR50, MTT90 and MTT50 values of cadmium were 0.2mM, 21.5mM, 1.0Mm and 60.0Mm, respectively.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.345.3-346
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• 2002

In connection with the asymmetric synthesis of chiral l.2-diol. we report here the total synthesis of (＋)-frontalin using diastereoselective alkylation featuring tridentate chelation-controlled asymmetric alkylation of a-hydroxyketone, in which the chiral auxiliary is attached to the hydroxyl group as ether linkage. The starting D-glyceraldehyde acetonide was converted (S)- ［(4R)-2.2-dimethyH,3-dioxolan-4-yl］ (4-methoxyphenyl) methanol. (omitted)

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3249-3253
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• 2014

A novel triazole-functionalized phenolic resin was developed, and its thermal and flame-retardant properties were investigated. The triazole group was incorporated as a pendant unit on the phenolic resin via copper-mediated click chemistry between propargylated phenolic resin and benzyl azide. The newly-developed triazole-functionalized phenolic resin showed higher thermal stability and char yield, together with a reduced total heat release (THR), than the non-functionalized bare phenolic resin, indicating enhanced flame retardancy for the triazole-functionalized phenolic resin.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.566-570
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• 2011

An efficient and general synthesis of bibenzyl derivatives bearing pyranyl rings was achieved by ethylenediamine diacetate-catalyzed reactions of 3,5-dihydroxybibenzyl with ${\alpha},{\beta}$-unsaturated aldehydes in moderate yields. These reactions provided naturally occurring compounds 1 and 2 in single step reaction. As an application of this methodology, biologically interesting natural bauhinol D (8) was synthesized by a convergent sequence from readily available benzaldehyde and benzyl phosphonate.

• YAKHAK HOEJI
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• v.45 no.4
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• pp.328-333
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• 2001

Ginsenoside Rh$_2$, a minor glycoside constituent of the red ginseng is known as an unique antitumor compound. Several attempts to prepare it in a large scale including semisynthesis from betulafolientriol, an 3-epimer of 20(S)-protopanaxadiol, has been reported. We have previously reported a synthesis of ginsenoside Rh$_2$from 20(S)-protopanaxadiol obtained by alkaline hydrolysis of total ginsenoside. The regioselective synthesis of this compound was achieved by protection of 12-OH group.

• Bulletin of the Korean Chemical Society
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• v.30 no.10
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• pp.2201-2202
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• 2009