• Journal of Nutrition and Health
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• v.22 no.4
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• pp.223-236
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• 1989

To evaluate the differences of the levels and sources of protein intake human protein metabolism, an 26-day metabolic balance study was conducted in 10 healthy Korean adult females. In the pre-study, the subjects recorded their own diets for 3 days. The metabolic balance study consisted of 6-day adaptation period, 10-day moderate protein period(60-65g/d) and 10-day high protein period(90-95g/d). During the moderate and high protein period, 5 subjects were fed the higher animal protein meals and the other 5 subjects were fed the high plant protein meals. Body weight, nitrogen balance and blood chemistries were monitored through out the study. The urine volume were sighificantly larger in the animal protein group and, the dietary fiber and fecal weights were significantly heavier in the plant protein diet group. But no statistically significant differences were found between the two dietary groups in apparent nitrogen digestability, urinary nitrogen excretion and nitrogen balance. Body weight, serum protein, albumin and HDL-cholesterol levels were not changed, but serum total cholesterol level in the animal protein diet group was elevated significantly from 143.8mg/dl on moderate potein diet to 173.0mg/dl on high proetin diet. In conclusion, from the observation of this short-term N balance study, plant diet on the adequate level of calorie and protein intake had almost the same effect of animal protein diet for protein maintenace in adults.

• Journal of Animal Science and Technology
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• v.47 no.5
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• pp.805-812
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• 2005

The aim of this study was to provide basic information to allow improved feeding management for velvet antler production by investigating the effects of dietary protein level on production and chemical composition of velvet antler in spotted deer(Cervus nippon). Eighteen male spotted deer of 5~6 years old were assigned to 3 unreplicated groups by production record of the previous year. Deer were fed on experimental diets at different protein level of 10%(T1), 15%(T2) and 20%(T3). Dry matter intake, crude protein intake and daily gain were increased with increasing the protein level in diets and there were significant differences(P<0.05) between groups. Although not significant, mean length of main beam tended to be longer in either left or right beam with increasing the protein level, and in girth at part of base of main beam, it was a similar pattern to the result of length. The velvet antler production was affected by dietary protein level and thus that was the smallest in T1 and the largest in T3(P<0.05). The content of crude protein in velvet antler was higher in T1 than in T3, whereas the content of crude ash in velvet antler was contrast to that of crude protein, however, there were no significant differences.

• Journal of Nutrition and Health
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• v.18 no.2
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• pp.98-114
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• 1985

In the previous studies, one of our author had observed the obligatory nitrogen losses through urine and feces in young Korean male adults, and utilization of whole egg protein in Korean young adults with ordinary intake of energy as a basic study for estimating protein requirements of Korean. This study has tried to determine the protein requirement and utilization when subjects ate the Korean mixed diet at the energy level of 45 kcal per Kg body weight per day. Six healthy Korean young female adults, college students, aged $20{\sim}25$ years old, and $45{\sim}61Kg$ of body weight participated as the study subjects. They were given isocaloric diets with four different protein levels for five days each successively. These diets contained protein levels of 0.45, 0.60, 0.75 and 0.90g per Kg of body weight per day, respectively. It was attempted to observe energy and protein intake, urinary and fecal nitrogen losses, true digestibility of protein, net protein utilization of protein in the body over last two days of period of eating each diet and nitrogen balances were calculated. The body weight change and hematological observation were also performed. The results obtained were summarized as follows ; 1) True digestibility of protein of Korean mixed diets ranged from 83.1% to 86.5% and the average of which was $84.7{\pm}1.7%$. 2) Net protein utilization rate of Korean mixed diets was range of 49% to 55% and the average of which was $52{\pm}3%.$ 3) The body weight of subjects were slightly increased and the values of hemoglobin and hematocrit of the blood were also little increased during the experimental periods of twenty days. 4) Protein requirements of Korean mixed diet with the energy level of 45 kcal/Kg body weight per day of Korean young female adults were estimated as 1.00g/Kg/day on this experimental condition.

• Journal of Dairy Science and Biotechnology
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• v.40 no.3
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• pp.134-142
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• 2022

Protein-enriched dairy powder is widely consumed to promote muscle synthesis. Recently, in Korea, elderly people have also begun consuming protein powder products to prevent muscle loss. However, these protein-enriched powders have poor flowability and hydration properties because of the fine particles of spray-dried milk protein powder. Therefore, in this study, the fluidized bed agglomeration process was used to solve these problems. The rheological and physical properties of milk protein isolate (MPI)/skim milk powder (SMP) mixtures were effectively improved via fluidized bed agglomeration. The particle size of the MPI/SMP mixtures significantly increased from 35.7-58 ㎛ to 118-136 ㎛, the flowability level improved from fair (21.4-26.3) to good (15.7-16.3), and the cohesiveness level changed from intermediate (1.27-1.36) to low (1.18-1.19) after fluidized bed agglomeration. In addition, the wetting time of the agglomerated MPI/SMP mixtures was effectively reduced to 4.67-58.3 s by fluidized bed agglomeration. These findings may be useful for manufacturing protein-enriched dairy powders with good instant properties.

• Journal of the Korean Home Economics Association
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• v.29 no.3
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• pp.47-59
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• 1991

This study wa performed to investigate the effects of dietary protein and fiber on the lead and protein metabolism in lead poisoning rats. Seventy male rats of Sprague-Dawley strain weighing 172$\pm$2g were blocked into 14 gropus according to body weight. Protein(casein) was given at levels of 15 or 40%, and fibers(pectin, cellulose and CMC) were given at levels of 0, 4 or 10%. The results are summarized as follows: 1. Food intake, weight gain and food efficiency ratio(FER) in groups fed high protein diets were higher than those in low protein groups. Liver weight in groups fed no dietary fiber was higher than that of animals fed fiber. Kidney and femur weights were greater in high protein groups. Tibia and femur lengths, and tibia weight were not significantly different among groups. 2. Hemoglobin content and hematocrit values showed no significant differance with dietary factors. 3. Total protein contents of serum and liver showed no significant difference, but tended to increase with increasing dietary protein level. Both daily urinary and fecal nitrogen excretions in high protein groups were higher than those in low protein groups. Especially daily fecal nitrogen excretions in high dietary fiber groups were significantly high. Body nitrogen absorption rate was the highest in animals fed no fiber. 4. Pb levels in blood, liver, kidney and bone tended to decrease with high dietary protein and fiber levels. Especially Pb level of kidney was high in all groups. Daily urinary Pb excretion showed no significant difference with dietary factors, but fecal Pb excretion increased significantly in high protein and fiber groups.

• Journal of Aquaculture
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• v.9 no.2
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• pp.167-168
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• 1996

Experiments were conducted to determine the activities of protease and carbohydrase in growing lensky sturgeon fed with three different diets containing various concentrations of protein and carbohydrate. Neutral pretense activity from growing lensky sturgeon the protein diet (predo-minary, almost $100\%$ protein) was lower then those from fish fed the other diets during the experimental period. The results may indicate that the level of pretense activity is inversely related to the level of protein in the diets.

• Journal of Nutrition and Health
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• v.19 no.5
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• pp.323-332
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• 1986

This study was performed to see the effects of lead poisoning and dietary protein levels(6, 15 and 40 % casein diets) on growth, protein and lipid metabolisms in growing rats. It was also investigated whether the high protein intake would alleviate lead toxicity by decreasing Pb absorption and/or increasing Pb excretion. The results obtained were summarized as follows ; 1) Weight gain, F.E.R liver weight, weight and length of bone in Pb-administered groups were lower than in Pb-free groups. However, these values in the 40% casein diet group with Pb were increased to the level in 15% casein diet group without Pb. 2) Hematocrt and hemoglobin content in blood were lower in Pb -adminstered groups than in Pb free groups. Especially, these levels were lower in 6% casein diet group with Pb than in any other group. 3) Plasma protein level in th e 40% casein casein diet group was the highest of all groups and those of Pb-administered groups tended to be lower than those of Pb-free groups. Plasma lipid and cholesterol levels were increased with decreasing dietary protein level, and these levels were higher in the animals exposed to Pb than in free groups.4) Total liver protein, lipid and cholesterol contents were increased with increasing dietary protein level, and these contents were lower in Pb-administered groups than in Pb free groups. 5) Fecal Pb excretion was not different between 6 and 40% casein diet groups. However, urinary Pb excretion was higher in the 40% casein diet group than in the 6% casein diet group. Above results suggest that, in exposing to the Pb pollution, sufficient protien intake must be recommended. High protein intake seemed to alleviate lead toxicity by increasing urinary Pb excretion.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1401-1406
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• 2013

This study tested the feasibility of observing H/D exchange of intact protein by top-down electron capture dissociation (ECD) mass spectrometry for the investigation of protein structure. Ubiquitin is selected as a model system. Local structural information was obtained from the deuteration levels of c and $z^{\cdot}$ ions generated from ECD. Our results showed that ${\alpha}$-helix region has the lowest deuteration level and the C-terminal fraction containing a highly mobile tail has the highest deuteration level, which correlates well with previous X-Ray and HDX/NMR analyses. We studied site-specific H/D exchange kinetics by monitoring H/D exchange rate of several structural motives of ubiquitin. Two hydrogen bonded ${\beta}$-strands showed similar HDX rates. However, the outer ${\beta}$-strand always has higher deuteration level than the inner ${\beta}$-strand. The HDX rate of the turn structure (residues 8-11) is lower than that of ${\beta}$-strands (residues 1-7 and residues 12-17) it connects. Although isotopic distribution gets broader after H/D exchange which results in a limited number of backbone cleavage sites detected, our results demonstrate that this method can provide valuable detailed structural information of proteins. This approach should also be suitable for the structural investigation of other unknown proteins, protein conformational changes, as well as protein-protein interactions and dynamics.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.3
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• pp.386-393
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• 2004

This study was conducted to investigate the effects of feeding dried leftover food (DLF) on growth, body composition and feed conversion of broiler chicks. One hundred ninety-six of one-day old Ross broiler chicks were assigned to 7 treatments in a completely randomized design. Each treatment had four replications with seven chicks per replication. The treatments groups included control without DLF, dietary 10% level of DLF, dietary 20% level of DLF and dietary 30% level of DLF, 5% higher protein level of diet containing 10% DLF, 10% higher protein level of diet containing 20% DLF and 15% higher protein level of diet containing 30% DLF than control diet. Body weight gain was slightly higher in control group than that of DLF-fed groups. However, there were no significant differences in body weight gain among those groups fed diets containing different levels of DLF. In general, increasing dietary level of DLF resulted in decreasing feed conversion. Content of crude protein in whole broiler body was slightly higher in control group although any significant difference was not found among treatments (p>0.05). Content of crude fat in whole broiler body was lowest in groups fed diets containing 30% DLF with 15% higher protein level than control diet, showing significant difference from groups fed diets containing 20% DLF (p<0.05). Contents of total cholesterol, free cholesterol, cholesterol ester and LDL- cholesterol in blood of broilers fed DLF-containing diets generally appeared to be higher compared with control group without significant difference (p>0.05). Fatty acid contents in broiler meat were higher in the order of oleic acid, palmitic acid and linoleic acid without significant differences among treatments. Content of DHA in broiler meat was higher in groups fed diets containing DLF than that of control group although there were no significant differences among treatments (p>0.05).

• Clinical and Experimental Pediatrics
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• v.59 no.10
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• pp.408-413
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• 2016

Purpose: This study investigated predictors of unresponsiveness to second-line intravenous immunoglobulin (IVIG) treatment for Kawasaki disease (KD). Methods: This was a single-center analysis of the medical records of 588 patients with KD who had been admitted to Asan Medical Center between 2006 and 2014. Related clinical and laboratory data were analyzed by univariate and multivariate logistic regression analyses. Results: Eighty (13.6%) of the 588 patients with KD were unresponsive to the initial IVIG treatment and received a second dose. For these 80 patients, univariate analysis of the laboratory results obtained before administering the second-line IVIG treatment showed that white blood cell count, neutrophil percent, hemoglobin level, platelet count, serum protein level, albumin level, potassium level, and C-reactive protein level were significant predictors. The addition of methyl prednisolone to the second-line regimen was not associated with treatment response (odds ratio [OR], 0.871; 95% confidence interval [CI], 0.216-3.512; P=0.846). Multivariate analysis revealed serum protein level to be the only predictor of unresponsiveness to the second-line treatment (OR, 0.160; 95% CI, 0.028-0.911; P=0.039). Receiver operating characteristic curve analysis to determine predictors of unresponsiveness to the second dose of IVIG showed a sensitivity of 100% and specificity of 72% at a serum protein cutoff level of <7.15 g/dL. Conclusion: The serum protein level of the patient prior to the second dose of IVIG is a significant predictor of unresponsiveness. The addition of methyl prednisolone to the second-line regimen produces no treatment benefit.