• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1326-1335
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• 2005

The main purpose of this study is to investigate the effects of dietary lysine deficiency on protein turnover of porcine muscles. There were 18 LYD three-breed-crossing postweanling barrows from six litters cannulated with gastric tubes through the esophagus at approximate 10 kg of body weight and allocated into three treatment groups. When their body weights reached over 12 kg, one group was sacrificed for determining the initial protein masses of m. masseter, m. longissimus dorsi, m. adductor and m. biceps femoris from the right body side. The others received a diet containing 100% or 61.4% (calculated values) of the lysine requirement (NRC, 1998) multiplied by 1.103 for a period of 17 days. Daily feed provision was computed for each pig according to body weight at the same day. All pigs were infused a flooding dose of $^2$H$_5$-phenylalanine to determine the fractional protein synthesis rates (FSR) of the aforementioned muscles in the end. Their four muscles from the right body side were also dissected for measuring the fractional rates of protein accretion (FAR). As for protein degradation, fractional rates (FDR) were calculated by differences between synthesis and accretion. Results showed that the lysine deficiency resulted in, significantly (p<0.05), lighter body weights, smaller muscles and a slower growth rate. The protein mass, accreted by the muscles, of the deficient group was only 54% averaged of the pigs fed adequately (p<0.05). The FAR of these muscles in the deficient group was significantly lower (p<0.05) and only achieved 61.1% averaged of the control; there was no significant difference (p>0.05), nevertheless, in the amino-acid composition of muscles between two groups. The lysine deficiency reduced significantly (p<0.05) the FSR of m. longissimus dorsi but did not influence its FDR. The m. biceps femoris also presented an inhibited FSR while its FDR reduced only exhibited a very high tendency (p = 0.055) compared to the adequately-fed pigs. As for the m. masseter and m. adductor, both of the FSR and FDR were depressed significantly (p<0.05) by the lysine deficiency, and changes in the FSR were severer than those in the FDR, so that their FAR were significantly slower (p<0.05) in comparison with the control group. The lysine deficiency also inhibited the RNA translation activity of the muscles while the effects on RNA capacity were not significant (p>0.05). In conclusion, the FAR of muscle protein was changed by the current lysine deficiency through the alterations in the FSR and/or FDR.

• Proceedings of the Botanical Society of Korea Conference
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• 1994.09a
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• pp.1-28
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• 1994

• The Korean Journal of Food And Nutrition
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• v.21 no.1
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• pp.71-78
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• 2008

This study examined the effects of mulberry-leaf powder Tofu(MPT) on the anthropometric measurements, bone mineral density(BMD), biochemical markers of bone turnover, serum lipid levels of and macrominerals status in 30 female university students living in Choongnam with low dietary Ca intake was low(mean daily $intake=524.66{\pm}21.47$ mg/day). The subjects received the MPT supplemented(100 g/day) for 4 weeks. The nutrient content per 100 g MPT was 84.10 kcal(energy), 8.98 g(protein), 0.53 mg(fiber), 211.33 mg(Ca) and 1.59 g(fat). Anthropometric measurements, 24-hour dietary recall, carpus BMD using DEXA, select BMD biomarckers(serum alkaline phophatase activity, osteocalcin, urinary deoxypyridinoline), serum protein levels, albumin, and glucose levels, lipid profiles(cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol) and serum macrominerals(Ca, Ca/P ratio, Mg) were analyzed before and after MPT supplementation. Following MPT supplementation, there was no significant differences in anthropometric measurements, nutrient intakes, carpus BMD, serum alkaline phosphatase activity, osteocalcin, and urinary deoxypyridinoline, serum levels of protein, albumin, and glucose or lipid profiles with AI, HTR, LHR and CRF. However, there were significant increases in dietary calcium as well as decreases in serum triglycerides with MPT supplementation. Although further research is needed, these results that regular intake MPT could prevent bone and cardiovascular diseases.

• Journal of Nutrition and Health
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• v.6 no.2
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• pp.1-16
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• 1973

Some effects of dietary conditions on the metabolism of nucleic acid and protein in organs of the Albino Rats have been studied. The young rats to be examined were fed on the control diet and the diets deprived of one component among protein, carbohydrate, and lipid, such as protein free diet (PF: 432 kcal/100g) carbohydrate free diet (CF: 432kcal/100g), and lipid free diet (LF: 392kcal/100g) for three, seven, and fifteen days, respectively. The contents of DNA and RNA in the liver and the brain, and also those of protein-nitrogen(PN) and nonprotein-nitrogen (NPN) in the live, the brain, and the serum have been measured. The results are as followe: 1. The contents of DNA per gram of liver were increased by feeding on protein free diet. It is concluded that the critical factor for the result is not the increase in the rates of DNA syntheses, but the decrease in the turnover rates of DNA. 2. The metabolism of DNA in the liver showed the normal status by feeding on carbohydrate free diet. On the other hand, the rates of DNA syntheses were increased by feeding on lipid free diet. 3. The rates of DNA syntheses in the brain were decreased by feeding on the unbalanced diet, such as protein free, carbohydrete free, and lipid free diet. 4. In the liver and the brain, the rates of DNA syntheses were decreased by feeding on protein free diet. But the rates showed the normal status by feeding on the carbohydrate free diet, and also showed the similar metabolism to that in the case of the control group by feeding on lipid free diet. 5. In the liver, the rates of protein syntheses were decreased, whereas the contents of nonprotein-nitrogen were increased by feeding on protein free diet. 6. In the liver and the brain, the protein syntheses showed the more increasing rates than the rates in the case of the control diet by feeding on lipid free diet. 7. In the serum, the contents of protein did not change in a short period, also the insufficient feeling on protein was examined. It is clear that in the liver the rates of protein syntheses are decreased and the rates of protein catabolism are increased, since the rates of nucleic acid syntheses are decreased by feeding on the protein free diet. On the other hand, it is considered that in the brain the turnover rates of protein does not have correlation with the rates of nucleic acid syntheses, also these are decreased by feeding on protein free diet. And also it is believed that the phenomena of homeostasis for carrying the normal metabolism of nucleic acid and protein in the liver and the brain are operated in a short period as possible, by feeding on carbohydrate free and lipid free diets.

• The Korean Journal of Zoology
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• v.30 no.2
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• pp.193-209
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• 1987

Patterns of amylase secretion in mouse pancreatic fragments were studied over a period of time after the tissue was stimulated by acetyicholine and MNNG. MNNG is known to activate guanylate cyclase and thus increase the cGMP concentration in the pancreatic acinar cell. These amylase secretion patterns were studied to investigate the role of cGMP in reaction cascade during secretion response of the tissues stimulated by acetyicholine. Cellular response of amylase secretion in the pancreas by acetyicholine was divided into two phases. During the first phase, zymogen granules which had existed in the cells were secreted by the action of $Ca^2$+ and calmodulin immediately after secretagogue administration, this being known as the initial response. When the tissue was stimulated by acetylcholine in a $Ca^2$+-deficient medium or one containing trifluoperazine as a calmodulin antagonist, this initial response was reduced. In the second phase, newly formed zymogen granules were secreted as sustained response after protein synthesis was triggered by secretagogue. This response was provoked by an activation of protein kinase C. When either cycloheximide as a protein synthesis inhibitor or dibucaine as a protein kinase C inhibitor were added to the incubation medium, this sustained response was remarkablely depressed in the pancreatic fragments stimulated with acetylcholine. In the pancreatic acinar cell, phosphatidylinositol turnover plays an important role in the secretion response and hexachlorocyclohexane inhibits this phosphatidylinositol turnover. The pancreatic tissue treated with the hexachlorocyclohexane exhibited inhibition on both initial and sustained responses of amylase secretion by acetylcholine. MNNG also accelerated amylase secretion from the tissue gradually along incubation time. The 22 minutes fraction of the pancratic secretion after administration of both acetylcholine and MNNG showed higher amylase activity than the neighboring fractions. Guanylate cyclase potentiated the sustained response. Even if it is experimented with an indirect method, guanylate cyclase was found responsible for activation of the sustained response of a step prior to the action of protein kinase C. As conclusion, it was considered that amylase secretion in mouse pancreatic fragments stimulated by acetylcholine is a three phasic response.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2081-2084
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• 2010

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.10
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• pp.1333-1339
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• 2010

The present study was conducted to determine plasma acetate, glucose and protein metabolism using dilution of isotopes [[1-$^{13}C$]Na acetate, [U-$^{13}C$]glucose and [1-$^{13}C$]leucine (Leu)] in sheep fed rice straw (Oriza japonica L.). Four sheep were assigned to either rice straw (RS-diet) or mixed hay (MH-diet) with a crossover design. Nitrogen (N) intake and N digestibility were lower (p = 0.002 and p = 0.02, respectively) for RS-diet than MH-diet, but N retention did not differ (p>0.10) between the diets. Concentrations of rumen acetate tended to be lower (p = 0.07), and propionate was higher (p = 0.02) for RS-diet than MH-diet. Concentrations of plasma lactate, non-esterified fatty acids, Leu and ${\alpha}$-ketoisocaproic acid did not differ (p>0.10) between the diets, but plasma glucose and urea concentrations were lower (p = 0.01 and p = 0.003, respectively) for RS-diet than MH-diet. Turnover rate of plasma acetate did not differ (p = 0.39) between the diets, and plasma glucose and Leu turnover rates were numerically lower (p = 0.15 and p = 0.14, respectively) for RS-diet than MH-diet. Whole body protein synthesis and degradation did not differ (p>0.10) between the diets. Thus it can be concluded that the intermediary metabolism of acetate, glucose and protein on rice straw is comparable to mixed hay in sheep.

• Korean Journal of Microbiology
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• v.31 no.1
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• pp.93-98
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• 1993

To investigate the organic matter transformation in aquatic environment, seasonal fluctuations of heterotrophic activity and microbia] extracellular enzyme activity were studied in Paldang Lake, Korea. The turnover time in the water column and the sediment at the station I fluctuated between 3 -I ,300 hrs and 17-170 hrs for glucose, 5 -1.900 hrs and 15-240 hrs for protein hydrolysate and 4-350 hrs and 15-230 hrs for acetic acid, respectively, indicating that the seasonal turnover time of organic substrates fluctuated drastically. The respiration ratios of glucose. protein hydrolysate and acetate were 23-32%, 38-41% and 22-28% in the water column and 34%, 61% and 41% in the sediment. respectively. These results showed that the respiration ratios in the sediment were higher than those in the water column regardless of kinds of organic substrates. The bacterial extracellular enzyme activities of $\alpha$-glucosidase. $\beta$-glucosidase, N-acetyl-$\beta$-D-glucosaminidase and aminopeptidase were 32-44%. 31-32%, 18-34% and 61-67% in the water column, and 34%. 40%, 23% and 65% in the sediment. respectively.

• International Journal of Industrial Entomology and Biomaterials
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• v.15 no.2
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• pp.165-169
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• 2007

A differential specific pattern of variation in the metabolism of protein and cholesterol was noticed in non -diapause and diapause eggs due to the significant differences in embryonic development. The rate of metabolism was different due to specific demands of such metabolites during active embryogenesis and maintenance of diapause respectively. In general, the metabolic rate was found to be accelerated in non- diapause eggs just after egg deposition, while it was very slow in diapause eggs. When the diapause eggs were treated with hydrochloric acid within 16-20 hrs, the rate of turnover was found to very similar to non- diapause eggs, though the base level of protein and cholesterol was recorded to be different.

• International Journal of Oral Biology
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• v.44 no.4
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• pp.125-129
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• 2019

Osteocalcin is the most abundant non-collagenous protein produced in bone. It has traditionally been regarded as a marker of bone turnover and is thought to act in the bone matrix to regulate mineralization. However, emerging knowledge regarding osteocalcin has expanded to include functions in energy metabolism, fertilization, and regulation of cognition. Fully carboxylated osteocalcin binds to hydroxyapatite, thereby modulating bone turnover, whereas undercarboxylated osteocalcin in the circulation binds to osteocalcin-sensing receptors and acts as a hormone that affects multiple physiological aspects. In this review, we summarize the current knowledge regarding the hormonal actions of osteocalcin in various organs and potential cellular downstream signaling pathway that may be involved.