• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.6
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• pp.1017-1021
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• 2004

To isolate a mutant which overproduces threonine and tryptophan, mutants of Saccharomyces cerevisiae were screened after UV and EMS mutagenesis. Hydroxynorvaline, a Thr analogue was used for selection of a Thr-overproducing mutant after UV mutagenesis. Among 31 mutants, TC 5-1 was selected as the strain candidate, based on amino acid analysis. TC 5-1 was then treated by EMS mutagenesis for Trp overproduction. Eight mutants were selected using fluorotryptophan for Thr and Trp overproducing strains. Amino acid analysis results showed that TC 6-1 was the best strain since it had the highest amount of Thr and Trp among mutants.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.1
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• pp.69-76
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• 2014

This study was carried out to evaluate the relationship between threonine (Thr) efficiency and Thr dehydrogenase (TDG) activity as an indicator of Thr oxidation on chicks fed with levels of diets (CP [17.5% and 21.5%] and Thr [3.8 and 4.7 g/100 g CP]; glycine [Gly][0.64% and 0.98%] and true digestible Thr [dThr] [0.45% and 0.60%]). Calculation of the Thr efficiency was based on N-balance data and an exponential N-utilization model, and TDG activity was determined as accumulation of aminoacetone and Gly during incubation of hepatic mitochondria. This study found that in the liver of chicks who received a diet containing up to 0.79% Thr (4.7 g Thr/100 g of CP) in the 17.5% CP diet, no significant (p>0.05) effect on TDG activity was observed. However, significantly (p = 0.014) increased TDG activity was observed with a diet containing 21.5% CP (4.7 g Thr/100 g of CP) and the efficiency of Thr utilization showed a significant (p = 0.001) decrease, indicating the end of the Thr limiting range. No significant (p>0.05) effect on the total TDG activity and accumulation of Gly was observed with addition of Gly to a diet containing 0.45% dThr. In addition, addition of Gly to a diet containing 0.60% dThr also did not result in a change in accumulation of Gly. Due to an increase in accumulation of aminoacetone, an elevated effect on total TDG activity was also observed. No significant (p>0.05) reduction in the efficiency of Thr utilization was observed after addition of Gly at the level of 0.45% dThr. However, significantly (p<0.001) reduced efficiency of Thr utilization was observed after addition of Gly at the level of 0.60% dThr. Collectively, we found that TDG was stimulated not only by addition of Thr and protein to the diet, but also by addition of Gly, and efficiency of Thr utilization was favorably affected by addition of Gly at the level near to the optimal Thr concentration. In addition, no metabolic requirement of Gly through the TDG pathway was observed with almost the same accumulation of Gly and a slight increase in TDG activity by addition of Gly. Thus, our findings suggest that determination of TDG activity and parameter of efficiency of Thr utilization may be useful for evaluation of dietary Thr level.

• Journal of Biomedical Engineering Research
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• v.16 no.1
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• pp.25-32
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• 1995

Clinically, proximal bone resorption in the femur is frequently seen postoperatively on the follow up XI-rays after total hip replacement (THR). We developed the finite element model of cementless THR. The model is two dimensional side plate model, whereby the three dimensional structural integrity of the bone can be accounted for by a separate two dimensional mesh, a side plate. The subject of this article is the development and application of this two dimensional side plate FEM to study the reverse effect of the various degree of bone resorption of femur after THR. The results of this study indicates that 1) two dimensional side plate model is good and simple alternative to complex three dimensional model and 2) the severity of the proximal bone resorption has the effect of more increasing stress on the cortex at the level of femoral stem tip.

• Journal of Biomedical Engineering Research
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• v.15 no.2
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• pp.183-188
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• 1994

In clinical orthopaedics, bone resoption in the cortex is often seen post operatively on X-rays or bone densitometry after total hip replacement (THR) in the form of cortical osteoporosis or atropy. Stress shielding of bone occurs, when a load, normally carried by the bone alone, is shared with an implant as a result, the bone stresses are abnormal and with remodelling analysis this may cause extensive proximal bone resoption, possibly weakening the bone bed to the point of failure. The author made finite element models of the cemented and non-cemented type implanted femoral stem with bone resorption of the proximal medial femur and studied the feed back effect of the various degree of bone resoption to THR system by parametric analysis on the stress of the femoral stem and interface. The results of the present finite element analysis implied that the extent of proximal bone resorption has the effect of more increasing stress on the distal stem tip, cement mantle and interface in both type of femoral stem and this high distal stress possibly can cause the mechanical failure of loosening or failure after THR.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.10
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• pp.4599-4608
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• 2016

Background: The x-ray repair cross-complementing group 3 (XRCC3) encodes a protein involved in the homologous recombination repair (HRR) pathway for double-strand DNA repair. Associations of the XRCC3 Thr241Met polymorphism with various cancers have been widely reported. However, published data on links between XRCC3 Thr241Met and gastrointestinal (GI) cancer risk are inconsistent. Objective and Methods: A meta-analysis was conducted to characterize the relationship between XRCC3 Thr241Met polymorphisms and GI cancer risk. Pooled odds ratios (ORs) and 95.0% confidence intervals were assessed using random- or fixed- effect models for 28.0 relevant articles with 30.0 studies containing 7,649.0 cases and 11,123.0 controls. Results: The results of the overall meta-analysis suggested a borderline association between the XRCC3 Thr241Met polymorphism and GI cancer susceptibility (T vs. C: OR=1.18, 9 % CI=1.0-1.4, POR=0.04; TT vs. CT+CC: OR=1.3, 95 % CI=1.0-1.6, POR=0.04). After removing studies not conforming to Hardy-Weinberg equilibrium (HWE), however, this association disappeared (T vs. C: OR=1.00, 95 % CI=0.9-1.1, POR=0.96; TT vs. CT+CC: OR=0.9, 95 % CI=0.8-1.1, POR=0.72). When stratified by ethnicity, source of controls or cancer type, although some associations between XRCC3 Thr241Met polymorphism and GI cancer susceptibility were detected, these associations no longer existed after removing studies not conforming to HWE. Conclusion: Our meta-analysis suggests that the XRCC3 Thr241Met polymorphism is not associated with risk of GI cancer based on current evidence.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.2
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• pp.224-233
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• 2012

The limiting sequence and relative ratio of lysine (Lys), methionine (Met), and threonine (Thr) for calves about 2 mo of age fed milk replacers (MR) containing soy protein are not clearly defined. The objective of the study was to investigate the effect of supplementing MR containing 22% CP, half from soy protein concentrate (SPC, 40.56% CP, flour) and half from whey proteins, with Lys, Met, and Thr to estimate amino acid (AA) sequence and their relative ratio for calves about 2 mo of age. A method of partial deduction of AA was adopted. Twenty-four newborn calves (half males and half females, $40.7{\pm}0.9$ kg of BW) were fed 1 of 4 MR diets for 56 d (n = 6/diet). The diets were supplemented with all (positive control) or with 2 of the 3 AAs: Lys, Met and Thr, (i.e., PC (22% CP, 2.34% Lys, 0.72% Met and 1.80% Thr), PC-Lys (22% CP, 1.64% Lys, 0.72% Met and 1.80% Thr), PC-Met (22% CP, 2.34% Lys, 0.50% Met and 1.80% Thr), and PC-Thr (22% CP, 2.34% Lys, 0.72% Met and 1.26% Thr)). Calves were fed thrice daily; starter (20% CP, 1.03% Lys, 0.30% Met and 0.69% Thr), hay (3.23% CP, 0.29% Lys, 0.12% Met and 0.23% Thr) and water were offered free choice. Starter and hay were only offered beginning on d 36 (after 5 wk) and d 43 (after 6 wk), respectively. BW, body size and blood samples measures were taken every two weeks. Three-day total collection of feed refusals, feces, and urine were recorded starting at d 33 and d 54 of age, respectively. From the results, the limiting sequence and relative ratio between the 3 AAs in calves with different diet structures were calculated. The limiting sequence of the 3 AAs were ranked as Lys, Met and Thr; the proper ratio was 100:29:70 for MR-only diet and 100:30:60 for diets consisted of MR, starter and hay. Nitrogen digestion and utilization and nutrient digestibility were negatively affected by AA deletion treatments. From the evidence of this experiment, it did not appear that the AA limiting sequence was selectively altered by differences in diet structures such as would be encountered in practice. The relative ratio between the 3 AAs varied with the offer of starter and hay to calves, and the average ratio was 100:29.5:65 for calves during 2 to 10 wk of age.

• Journal of Aquaculture
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• v.15 no.3
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• pp.157-163
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• 2002

Thirteen groups, each consisting of 25 juveniles (0.64 g) of the Korean rockfish, Sebastes schlegeli were reared in aquaria after period of one week conditioning. Each group was fed with one of the 13 diets at the rate of 7~10% body weight (on a dry-matter basis) 2 times a day for 6 weeks. Each diet was supplemented with one of the following amino acids at 3g/kg diet: Alanine (Ala), Arginine (Arg), Glycine(Gly), Glutamate (Glu), Histidine (His), Isoleusine(Ile), Lysine (Lys), Methionine (Met), Phenylalanine (Phe), Proline (Pro), Threonine (Thr), Tryptophan (Trp) or Valine (Val). Groups fed with Pro, Thr, Met or Gly-supplemented diet showed significantly (p<0.05) higher weight gain and faster specific growth rate than the groups fed on other diets, while those fed Pro, Thr, Met or Gly were not significantly different each other(P>0.05). Feed efficiency (FE) of fish fed Pro was significantly higher than those fed the other diets except that fed Thr (P<0.05). However, there was no significant difference between FE of fish fed Pro and Thr, and among FE of fish fed Thr, Met and Gly (P>0.05). The requirement of rockfish is higher for Met and Thr. Extra Pro and/or Gly may also stimulate biosynthesis of the nucleic acids (IMP, GMP) which are known as the feed stimulant in fish.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.496-501
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• 2006

This study was to isolate a bacterium producing a alkaline protease from mud flats of the west seaside of Korea and to investigate the biochemical analysis of the alkaline protease producing from the isolate. The isolate was named as Gelidibacter sp. HK-1 based on 16S rRNA sequence, Gram staining and the photograph of electron microsceope. Optimum temperature for growth and pretense production of the isolate was $25^{\circ}C$. Growth of the isolate was reached at stationary phase after 10hrs followed by inoculation. Maximum activity of protease produced from the isolate was shown after 14hrs. Optimum temperature and pH for the protease activity were $45^{\circ}C$ and pH 9, respectively. Molecular weight of the pretense was about 50KD and the partial amino acid sequence of the pretense was Ala-Try-Ala-Leu-Asn-Thr-Ser-Val-Thr-Glu-Thr-Phe-Ala-Lys. The partial amino acid sequences of the protease showed significant homology with a pretense produced from Streptomyces avermitilis.

• Journal of Microbiology
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• v.39 no.4
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• pp.314-320
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• 2001

Macrophages stimulated by lipopolysaccharide(LPS) from gram negative bacteria undergo activation of a group of immediate early genes including Rantes. The mouse Rantes gene promoter region contains an LPS rsponsive element(LPE) We detected 3 specific bands termed B1, B2 and 3 formed by the interaction of the LPE and proteins found in LPS-stimulated RAW 367.7 cells. An additional band B4 was determined to be an Ap-1 binding protein. The B1 band appears within 1 hour of LPS nuclear extracts from LPS-stimulation, and this protein kinase enhances B1 and formation. The B1 band can be converted to band B2/B3 by adding specific heparin column fraction purified Ser/Thr specific protein phosphatases PP-1 and PP-2A can stimulate the same conversion to about the same extent. Thus, the formation of the LRE sequence binding complex appears to be regulated by Ser/Thr protein kinase and one or more Ser/Thr specific phosphatases. At least four proteins are involved in the trgulation of the LRE-dependent Rants experssion: two binding factors that bind directly to the target sequences. and two factors that control their binding. The future purification and characterization of these binding pro-teins will reveal in detail the mechanism of Rantes gene activation after LPS stimulation.

• Proceedings of the KOSOMBE Conference
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• v.1994 no.12
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• pp.75-78
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• 1994

Clinically, proximal bone resorption in the femur is frequently seen postoperatively on the follow up X-rays after total hip replacement(THR). We developed the finite element model of cementless THR. The model is two dimensional side plate model, whereby the three dimensional structural integrity of the bone can be accounted for by a separate two dimensional mesh, a side plate. The subject of this article is the development and application of this two dimensional side plate FEM to study the reverse effect of the various degree of bone resorption of femur after THR. The results of this study indicates that two dimensional side plate model is good and simple alternative to complex three dimensional model and the severity of the proximal bone resorption has the effect of more increasing stress on the cortex at the level of femoral stem tip.