• Journal of Microbiology
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• 제33권3호
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• pp.191-195
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• 1995

IciA protein has been shown as an inhibitor for the initiation of E. coli chromosomal DNA replication at oriC. IciA protein binds the AT-rich region in oriC and then blocks the initiation of chromosomal DNA replication. Two binding sites for IciA protein were identified in dnaA gene, encoding the initiator for the E. coli chromosomal replication, promoter region by gel-shift assay and DNase I footprinting, One, named as IciA site I, is located upstream of the dnaA promoter 1P. The other, named as IciA site II, is located downstream of the dnaA promoter 2P. The sequence comparison of the regions protected from the DNase I cleavage did not result in a clear consensus sequence for the binding of IciA protein, suggesting that IciA protein may be a member of multimeric complex dsDNA binding proteins. This study provided information about the binding mode of IciA protein. Even though the IciA site II and IciA binding site in oriC seem to be composed of two IciA binding units, one binding unit is likely enough to cause the binding of IciA protein to the IciA site I. The binding of IciA protein to the dna4 promoter implies that IciA protein may involve not only the control of the initiation of chromosomal DNA replication but also the control of the dna4 gene expression.

• 한국초지조사료학회지
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• 제28권3호
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• pp.255-264
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• 2008

본 연구는 반추위 보호 choline의 급여가 in vitro 반추위 발효특성과 착유우의 유생산성에 미치는 영향을 검토하기 위해 수행되었다. 시험구 배치는 기초사료 첨가구(T1), 기초사료 +23 g/일 보호처리를 하지 않은 choline과 부형제 첨가구(T2) 및 기초사료+ 25.56 g/일 보호 choline 첨가구(T3)의 3처리로 하였다. 보호 choline의 첨가가 in vitro 배양액의 pH에 미치는 영향은 3시간을 제외한 전 배양시간에서 없었으며, ammonia 농도에 대한 보호 choline의 영향도 배양 9시간을 제외한 전 배양시간에서 없었다. 보호 choline의 첨가가 acetate 및 total-VFA 농도에 미치는 영향은 없었으며, propionate 및 butyrate 농도의 경우 배양 6시간을 제외한 전 배양시간에서 보호 choline 첨가의 영향도 없었다. 보호 choline의 급여로 착유우의 산유량과 유지방 및 유당 함량이 증가되었으나(p<0.05), 보호 choline의 급여가 착유우의 유단백질, 무지고형분, 총고형물, MUN, 체세포 수 및 지방산에 미치는 영향은 없었다. 따라서 반추위 보호 choline은 in vitro 반추위 발효에 대한 별다른 영향 없이 산유량과 유지방 및 유당 함량을 증가시키는데 효과적인 것으로 판단된다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권9호
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• pp.1235-1238
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• 2000

Thirty-six Holstein dairy cows were used to evaluate the effect of a rumen protected methionine supplement (RPMet). The cows were divided into two groups of 18 each (control/experimental). The experimental group was given 15 g/d of RPMet (Mepron $^{(R)}$M85, Degussa) from the 4th to the 26th week postpartum. All cows were fed a similar amount of forage including alfalfa silage, corn silage and timothy silage. Concentrate mixture was offered in proportion to the milk yield of each cow. Sufficiency of major metabolizable AAs was checked. Milk yield and milk composition was monitored for each individual cow. A metabolic profile test (MPT) was carried out at the 7th, 11th and 21st week postpartum. Without supplement, both methionine and leucine fell short of the daily requirement. Supplementation with 15 g/d RPMet was calculated to be within a sufficient margin of safety. Milk yield tended to remain higher in the supplemented group than in the controls during supplementation with RPMet. The differences in weekly milk production at the 17th, 18th, 19th and 22nd weeks postpartum were significantly high in the RPMet group (p<0.05). The average 305-d milk yield and the percentages of milk fat, milk protein and solids-not-fat were not affected by the treatment. No differences were observed in either the somatic cell count in the milk or the reproductive status. Judging from MPT, all the cows were in good health during lactation.

• Animal Bioscience
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• 제36권11호
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• pp.1666-1684
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• 2023

Objective: Our objective was to examine the relationships of supplemental rumen-protected lysine (RPL) or lysine + methionine (RPLM) on lactational performance, plasma amino acids (AA) concentration, and nitrogen use efficiency of lactating dairy cows by using a meta-analysis approach. Methods: A total of 56 articles comprising 77 experiments with either RPL or RPLM supplementation were selected and analyzed using a mixed model methodology by considering the treatments and other potential covariates as fixed effects and different experiments as random effects. Results: In early lactating cows, milk yield was linearly increased by RPL (β₁ = 0.013; p<0.001) and RPLM (β₁ = 0.014; p<0.028) but 3.5% fat-corrected milk (FCM) and energy-corrected milk (ECM) (kg/d) was increased by only RPL. RPL and RPLM did not affect dry matter intake (DMI) but positively increased (p<0.05) dairy efficiency (Milk yield/DMI and ECM/DMI). As a percentage, milk fat, protein, and lactose were unchanged by RPL or RPLM but the yield of all components was increased (p<0.05) by feeding RPL while only milk protein was increased by feeding RPLM. Plasma Lys concentration was linearly increased (p<0.05) with increasing supplemental RPL while plasma Met increased (p<0.05) by RPLM supplementation. The increase in plasma Lys had a strong linear relationship (R² = 0.693 in the RPL dataset and R² = 0.769 in the RPLM dataset) on milk protein synthesis (g/d) during early lactation. Nitrogen metabolism parameters were not affected by feeding RPL or RPLM, either top-dress or when supplemented to deficient diets. Lactation performance did not differ between AA-deficient or AA-adequate diets in response to RPL or RPLM supplementation. Conclusion: RPL or RPLM showed a positive linear relationship on the lactational performance of dairy cows whereas greater improvement effects were observed during early lactation. Supplementing RPL or RPLM is recommended on deficient-AA diet but not on adequate-AA diet.

• Journal of Applied Biological Chemistry
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• 제65권4호
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• pp.307-312
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• 2022

A hair essence containing α-tocopheryl acetate, retinyl palmitate, and phytantriol (TRP-hair essence) was prepared. TRP-hair essence was excellent in thermal stability to the extent that it did not harden at all even at 210 ℃. TRP-hair essence potently protected the hair from heat stress, significantly reducing the protein leakage in heat-treated hair (p <0.001). Treatment of TRP-hair essence to dyed human hair significantly protected hair against heat stress (p <0.05) as well as improved hair cuticle and color persistence (p <0.05). In addition, as a result of directly treating human hair with TRP-hair essence, the cuticle and tensile strength of human hair were significantly improved (p <0.05). These results suggest that TRP-hair essence can be effective for hair protection and hair quality improvement.

• BMB Reports
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• 제30권3호
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• pp.211-215
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• 1997

A photoactive analog of ATP, 3'(2')-O-(p-azidobenzoyl)-adenosine 5-triphosphate (AB-ATP) was synthesized by chemically coupling N-hydroxysuccinimidyl-4-azidobenzoate (NHS-AB) and ATP. The utility of AB-ATP as an effective active-site-directed photoprobe was demonstrated using catalytic subunit of protein kinase A as a model enzyme. Photoincorporation of AB-ATP was saturated with apparent dissociation constant of $30{\mu}m$ and protected completely by $100{\mu}m$ of ATP. When the enzyme was covalently modified by photolysis in the presence of saturating amounts of photoprobe, about 60% inhibition of enzyme activity was observed. These results demonstrate that AB-ATP has potential application as a probe to characterize ATP-binding proteins including protein kinases.

• 생명과학회지
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• 제10권5호
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• pp.475-483
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• 2000

Normally, aerobic cells are protected from the damage of free radicals by antioxidative enzymes such as catalase, superoxide dismutase (SOD), glutathione (GSH) peroxidase and GSH-S-transferase. In this study, we have investigate the effect of egg yolk protein hydrolysates on antioxidative activity and the activity of antioxidative enzyme in cultured hepatocytes (Chang). Without the pretreatment with hydrolysate, about 50% of the hepatocytes were killed within 2h by 225$\mu$M tert-butyl hydroperoxide (t-BHP). By contrast, fewer than 20% of the 5 K hydrolysate (permeate from 5 kDa membrane and not passed through 1 kDa membrane)-pretreated hepatocytes were killed by the same concentrations of t-BHP. In addition, the activities of catalase, GSH peroxidase and GSH-transferase were significantly increasing with the treatment of 5 K hydrolysate. These results suggest that 5 K hydrolysate exerts antioxidative effect by increasing activity of antioxidative enzymes.

• 생약학회지
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• 제38권2호통권149호
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• pp.152-156
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• 2007

Protein-bound polysaccharide is derived from Acanthopananx senticosus by the cold water extraction. The aim of the study was to evaluate the effects of PS against weight loss and hematological change as a indication of toxicity produced by the treatment of cisplatin. PS protected the weight loss caused by cisplatin (6 mg/kg) and significantly recovered hematological change. Treatment of PS showed the recovery on the weight loss and hematological change as indicators of toxicity of cisplatin treatment. By increasing lymphocyte proliferation and cytokine production, PS may be highly effective in protecting against cisplatin-induced toxicity. The results suggest PS might have a role in reducing toxicity or permitting larger dose of cisplatin to be given.

• 한국자원식물학회지
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• 제23권3호
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• pp.207-213
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• 2010

Hovenia dulcis Thunb fruits were successively extracted with hot water, water, methanol, ethyl acetate, and chloroform. The crude extracts were investigated for potential antioxidant by measuring scavenging against DPPH free radicals, reducing power, superoxide radicals, and protection of protein damage and cultured cells from a lethal dose of hydrogen peroxide ($H_2O_2$). In all chemical assays used, the hot water extract of H. dulcis fruits, which contained $61.14{\pm}2.57$ (Tannic acid mg/g extract, n=3) of total phenolic compounds contents exhibited highest activity in in vitro models of DPPH free radical scavenging activity, reducing power assay, superoxide radical scavenging activity and protection of protein damage. In addition, the hot water extract protected cultured RAW 264.7 macrophages from a lethal dose of $H_2O_2$ and reduced reactive oxygen species level in RAW 264.7 cells.

• Animal Bioscience
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• 제36권11호
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• pp.1685-1692
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• 2023

Objective: This study was conducted to investigate the effects of rumen-protected biotin (RPB) on growth performance, nutrient digestibility, nitrogen utilization and plasma biochemical parameters of Liaoning cashmere goats during the cashmere fiber growing period. Methods: Sixteen 6-month-old Liaoning cashmere twin-doelings (24.8±1.20 kg) were allocated to 2 diet groups that were individually ad libitum fed 30% concentrate and 70% forage diet (dry matter [DM]) by a paired experimental design. Goats of the control group were fed the basal diet, while goats belonging to the RPB group were fed the basal diet with 10 mg RPB/d per animal. The duration of the experiment was 16 weeks with two 8-week periods. Digestibility was determined at weeks 7 and 15, and other measures were taken every four weeks. Results: Compared with the control group, the average daily gain of the RPB group increased by 10.94% (p<0.05), and the intake of neutral detergent fiber was increased (p = 0.045). There were some increasing tendencies for the intake of DM, acid detergent fiber and ether extract (p = 0.070, 0.088, and 0.070, respectively). The intake and digestibility of N tended to increase (p = 0.062 and 0.093, respectively), while the N fecal excretion percentage of N intake was decreased (p = 0.093) in the RPB compared with the control group. N retention tended to increase (p = 0.084) with the addition of adding RPB to the diet. Plasma total protein was increased (p = 0.037), whereas the urea-N concentration was decreased (p = 0.049) in the RPB diet group compared with the control diet group. The levels of propionyl-CoA carboxylase (p<0.001) and methylmalonyl-CoA (p = 0.013) were increased in the RPB group. Conclusion: Supplementation of rumen-protected biotin in the diet of cashmere goats can enhance the utilization of N and improve daily weight gain during cashmere fiber growing period.