• Communications of the Korean Mathematical Society
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• v.11 no.3
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• pp.569-573
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• 1996

We study some special cases of Chow groups of a ramified complete regular local ring R of dimension n. We prove that (a) for codimension 3 Gorenstein ideal I, [I] = 0 in $A_{n-3}(R)$ and (b) for a particular class of almost complete intersection prime ideals P of height i, [P] = 0 in $A_{n-i}(R)$.

• Korean Circulation Journal
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• v.53 no.2
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• pp.92-102
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• 2023

Background and Objectives: YKL-40 is considered to be associated with cardiovascular disease (CVD). In this study, the effect of serum 25(OH) vitamin D [25(OH)VitD] differences between groups on YKL-40 was evaluated on a hypercholesterolemia rat model. Methods: Thirty-two male rats (wistar albino) were equally divided into 4 groups. The first group was the control group; the second group was high-cholesterol (H-CH) adequate vitamin D (VitD) group (H-Ade^VD). The third group was the H-CH deficient VitD group (H-Def^VD), and the last group was designed with the H-CH supplement VitD (H-Sup^VD). The feeding process consisted of 2 stages. At the first stage (5 months), the H-Def^VD group was fed on VitD deficient chow, while the other groups (control, H-Ade^VD, H-Sup^VD) were fed on standard chow. At the second stage (3 months), the H-Ade^VD and the H-Sup^VD groups were fed on the H-CH chow, whereas the H-Def^VD group was fed on the H-CH-VitD deficient chow. Moreover, the H-Sup^VD group was given 100 IU/kg/day VitD along with the H-CH chow. Results: Compared with the control group, interleukin-6 (IL-6), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), and YKL-40 values in the H-Def^VD groups increased significantly (p<0.001, p<0.001, p=0.009, p=0.005; sequentially). Conclusion: It can be concluded that VitD can suppress the YKL-40, thus, it will prevent CVD development in rat. Therefore, further clinical studies related with human will reveal the effect of VitD and YKL-40 on CVD development.

• Communications of the Korean Mathematical Society
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• v.17 no.2
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• pp.221-227
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• 2002

In this paper we will show that the followings ; (1) Let R be a regular local ring of dimension n. Then $A_{n-2}$(R) = 0. (2) Let R be a regular local ring of dimension n and I be an ideal in R of height 3 such that R/I is a Gorenstein ring. Then [I] = 0 in $A_{n-3}$(R). (3) Let R = V[[ $X_1$, $X_2$, …, $X_{5}$ ]]/(p+ $X_1$$^{t1}$ + $X_2$$^{t2}$ + $X_3$$^{t3}$ + $X_4$$^2$+ $X_{5}$ $^2$/), where p $\neq$2, $t_1$, $t_2$, $t_3$ are arbitrary positive integers and V is a complete discrete valuation ring with (p) = mv. Assume that R/m is algebraically closed. Then all the Chow group for R is 0 except the last Chow group.group.oup.

• Journal of Nutrition and Health
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• v.31 no.7
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• pp.1100-1111
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• 1998

The incorporation of docosahexaenoic acid(DHA) and arachidonic acid(AA) into brain and liver lipid has been compared in male pups from binth to 10 weeks old by feeding DHA-rich experimental diets or chow diets to dams from pregnancy in rats. The experimental DHA-rich diets contained 7g fish oil and 3g corn oil per 100g diet. There were three experimental groups, FO-I : Dams were fed DHA-rich diet during pregnancy and lactation, and their it pups fed the same diet until 10 weeks old. FO-II Dams fed chow diet during pregnancy and DHA-diet during lactation, and their pups fed the same DHA-diet until 10 weeks. FO-III : Dams fed chow diet during gestation and lactation, and then the pups fed DHA-diet after weaning. The relative % of DHA in hepatic lipid was about 12% with chow diets, but increased rapidly to 20-25% level when DHA-rich diets were supplied after weaning. The AA(%) of FO-III group was relatively high when a chow diet containing higher amount of linoleic acid was given, but there was no significant difference between the groups after feeding on a DHA-rich diet. When the DHA-rich diet was supplied from pregnancy(FO-I), the relative % of DHA in brain lipid was 13.7% at birth and continuously increased to a maximum level(17.2%) at 3-weeks and then was sustained until 5 weeks old. Similar levels of DHA incorporation were observed when DHA-rich diet was supplied from lactation(FO-II). However, the pups of FO-III group showed significantly lower levels of DHA incorporation(72%) at birth. These livels slowly increased and reached an 87% level of FO-I at 10 weeks when the pups ate DHA-rich diets after weaning. The relative % of AA in brain lipid was 10.4% in the FO-I group at birth, which was significantly lower than those of other groups, but there was no significant difference between groups after feeding DHA-rich diets in all groups. The Ah(%) level increased to maximum(11-12%) at 3-weeks and then was slightly reduced and was sustained at about 10% after S-weeks. Total amounts of DNA in the whole brain rapidly reached maximum level at 3-weeks and then was sustained at a constant level after S-weeks. DNA content was not significantly different between groups at birth, but it was significantly higher in FO-I and FO-II groups than in FO-III group at 3-weeks. However, DNA content in FO-III group was continuously increased to 80% level of FO-I at 10-weeks after feeding DHA-rich diet since weaning. In conclusion, the DHA(%) in whole brain was most effectively deposited when DHA-rich diet had been supplied during pregnancy and lactation in rats. However, DHA supplementation after weaning also improved the incorporaton of DHA into brain and content of DNA even though brain development was almost completed, which suggests that DHA supplementation might be necessary to improve brain development in humans during infancy as well as pregnancy and lactation. (Korean J Nutrition 31(7) 1100-1111, 1998)

• Korean Journal of Exercise Nutrition
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• v.13 no.2
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• pp.93-100
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• 2009

This study was conducted to investigate the effect of exercise training on blood and metabolic variances and genes expressions in hyperlipidemic rats. Three weeks-old male rats were randomly assigned into chow (n=7), high-fat diet (HF, n=7) and HF+exercise (HF+EX, n=7) groups. Exercise training consisted of the treadmill running 5 times per week during 8 weeks (0% grade, 30 min/time for first 4 weeks and 0% grade, 60 min/time the other 4weeks). The levels of triglyceride and total -cholesterol were increased in HF diet compared with chow group, and recovered to level of chow group by exercise training. Plasma glucose and insulin concentrations increased by 40 and 50%, respectively in HF diet compared with chow diet group, and these increases returned to the level of chow group by exercise training (p<.05). Body weight and abdominal fat mass were increased by high-fat diet compared with chow diet, and recovered to level of chow group by exercise training. Long-chain fatty acid oxidation rate and AMPK protein expression was not changed by HF diet, but increased by exercise training compared with high-fat diet (p<.05). UCP3 protein expression was not changed by either high-fat diet or exercise training compared with chow group. There was high correlation between plasma triglyceride and total cholesterol concentrations(p<.01). Plasma triglyceride or total cholesterol level showed correlation with following factors; plasma insulin and glucose levels, body weight, abdominal fat weight, UCP3 protein expression and long-chain fatty acid oxidation rate. These results showed that exercise training on the treadmill recovered hyperlipidemia, hyperglycemia and hyperinsulinemia induced by high-fat diet for 8 weeks. These exercise effects may be related with decreased body weight and abdominal fat mass, and increased long-chain fatty acid oxidation rate.

• Nutritional Sciences
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• v.8 no.3
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• pp.181-188
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• 2005

We investigated the effects of diet manipulation on pro- and macro-glycogen accumulation and mobilization during exercise in different kinds of muscle fiber and tissue. Thirty-two Sprague-Dawley rats were divided into groups representing one of two dietary conditions: high fat (HF, n=16) or standard chow (CHOW, n=16). Each dietary group was fm1her divided into control (REST, n=8) and exercise (EXE, n=8). After an eight-week dietary intervention period, the animals in EXE swam for 3 hours while the animals in REST remained at rest Skeletal muscle (soleus, red gastrocnemius and white gastrocnemius) and liver samples were then dissected out and used for analyses. 1here was no statistical difference in body weight between the animals in the HF and mow groups (p>.05). Three hours of exercise significantly increased plasma free fatty acid (FFA) concentration in the animals in the CHOW group but not in the animals in the HF group. Both citrate. synthase (CS) and $\beta$-hydroxyacyl dehydrogenase ($\beta$-HAD) activities in skeletal muscles were higher in the HF group than in the mow group. CS and $\beta$-HAD activities were also the highest in red gastrocnemius and the lowest in white gastrocnemius. At both time points (i.e., rest and immediately after exercise) intramuscular triglyceride (IMTG) and liver TG concentrations were significantly higher in the HF compared to the CHOW. IMTG and liver TG changed selectively in the CHOW. Except in white gastrocnemius muscle, there was no significant difference in total glycogen content between HF and mow at rest. Although exercise significantly lowered total glycogen content in all groups and tissues (p<.05), the degree of reduction was markedly greater in the mow than in the HF. Whereas changes in proglycogen concentration showed a trend similar to those of total glycogen, alterations in macroglycogen concentrations clearly differed from those of total glycogen. Specifically, the degree of reduction of macroglycogen following three hours of exercise was substantially greater in the CHOW than in the HF. These results suggest that metabolic alterations induced by a long-term high fat diet may be caused by macro-glycogen rather than pro-glycogen.

• Journal of the Korean Mathematical Society
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• v.54 no.6
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• pp.1841-1851
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• 2017

Motivated by the Bloch-Beilinson conjectures, Voisin has made a conjecture concerning zero-cycles on self-products of Calabi-Yau varieties. We reformulate Voisin's conjecture in the setting of $hyperk{\ddot{a}}hler$ varieties, and we prove this reformulated conjecture for one family of $hyperk{\ddot{a}}hler$ fourfolds.

• Journal of Nutrition and Health
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• v.40 no.3
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• pp.211-220
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• 2007

The purpose of this study was to investigate that the effect of dietary fatty acid composition on pro- and macro-glycogen utilization and resynthesis. The analyses were further extended for different muscle fibers (type I, type II, & type IIb) as well as tissues (i.e., liver & heart). Total one hundred sixty Sprague-Dawley rats were used, and rats were randomly allocated into four experimental groups: animals fed standard chow diet (n=40), animals fed saturated fatty acid diet (n=40), animals fed monounsaturated fatty acid (n=40), and animals fed polyunsaturated fatty acid (n=40). Animals in each groups were further divided into five subgroups: sacrificed at REST (n=8), sacrificed at immediately after 3 hr swim exercise (P-0HR, n=8), sacrificed at one hour after 3 hr swim exercise (P-1HR, n=8), sacrificed at four hour after 3 hr swim exercise (P-4HR, n=8), and sacrificed at twenty-four hour after 3 hr swim exercise (P-24HR, n=8). Soleus (type I), red gastrocnemius (type IIa), white gastrocnemius (type IIb), liver, and heart were dissected out at appropriated time point from all animals, and were used for analyses of pro- & macro-glycogen concentrations. After 8 weeks of dietary interventions, there was no significant difference in body mass in any of dietary conditions (p>.05). After 3 hr swim exercise, blood lactate level was higher compared to resting conditions in all groups, but it was returned to resting value after 1 hr rest (p<.05). Free fatty acid concentration was higher in all high fat fed groups(regardless of fatty acid composition) than CHOW consumed group. At rest, pro- & macro-glycogen concentration was not different from any of experimental groups (p>.05). Regardless of forms of glycogen, the highest level was observed in liver (p<.01), and most cases of supercompensation after 3hr exercise observed in this study were occurred in CHOW fed tissues. Except heart muscle, all tissues used in this study showed that pro- and macro-glycogen concentration was significantly decreased after 3 hr exercise. Based on these results, two conclusions were made: first, there is no different level of glycogen content in various tissues regardless of types of fatty acids consumed and second, the highest mobilization rate would be demonstrated from CHOW fed animals compare to animals that consumed any kinds of fatty acid diet if prolonged exercise is applied.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.6
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• pp.633-641
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• 2017

The aim of this study is to investigate the effects of intermittent ladder-climbing exercise training on mitochondrial biogenesis and ER stress of the cardiac muscle in high fat diet-induced obese middle-aged rats. We induced obesity over 6 weeks of period in 40 male Sprague-Dawley rats around 50 weeks old, and were randomly divided into four experimental groups: chow, HFD, exercise+HFD, and exercise+chow. The exercising groups underwent high-intensity intermittent training using a ladder-climbing and weight exercise 3 days/week for a total of 8 weeks. High-fat diet and concurrent exercise resulted in no significant reduction in body weight but caused a significant reduction in visceral fat weight (p<0.05). Expression of $PPAR{\delta}$ increased in the exercise groups and was significantly increased in the high-fat diet+exercise group (p<0.05). Among the ER stress-related proteins, the expression levels of p-PERK and CHOP, related to cardiac muscle damage, were significantly higher in the cardiac muscle of the high-fat diet group (p<0.05), and were significantly reduced by intermittent ladder-climbing exercise training (p<0.05). Specifically, this reduction was greater when the rats underwent exercise after switching back to the chow diet with a reduced caloric intake. Collectively, these results suggest that the combination of intermittent ladder-climbing exercise training and a reduced caloric intake can decrease the levels of ER stress-related proteins that contribute to cardiac muscle damage in obesity and aging. However, additional validation is required to understand the effects of these changes on mitochondrial biogenesis during exercise.

• Korean Journal of Exercise Nutrition
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• v.24 no.1
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• pp.19-23
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• 2020

[Purpose] Blood glucose and insulin resistance were lower following hypoxic exposure in previous studies. However, the effect of hypoxia as therapy in obese model has not been unknown. [Methods] Six-week-old mice were randomly divided into chow diet (n=10) and high-fat diet (HFD) groups (n=20). The chow diet group received a non-purified commercial diet (65 % carbohydrate, 21 % protein, and 14 % fat) and water ad libitum. The HFD group was fed an HFD (Research Diet, #D12492; 60% kcal from fat, 5.24 kcal/g). Both groups consumed their respective diet for 7 weeks. Subsequently, HFD-induced mice (12-weeks-old) were randomly divided into two treatment groups : HFD-Normoxia (HFD; n=10) and HFD-Hypoxia (HYP; n=10, fraction of inspired=14.6%). After treatment for 4 weeks, serum glucose, insulin and oral glucose tolerance tests (OGTT) were performed. [Results] Homeostatic model assessment values for insulin resistance (HOMA-IR) of the HYP group tended to be lower than the HFD group. Regarding the OGTT, the area under the curve was 13% lower for the HYP group than the HFD group. [Conclusion] Insulin resistance tended to be lower and glucose uptake capacity was significantly augmented under hypoxia. From a clinical perspective, exposure to hypoxia may be a practical method of treating obesity.