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Growth Characteristics of a Pyruvate Decarboxylase Mutant Strain of Zymomonas mobilis (Pyruvate decarboxylase 돌연변이 Zymomonas mobilis 균주의 생장 특성 연구)

  • Xun, Zhao;Peter L., Rogers;Kwon, Eilhann E.;Jeong, Sang Chul;Jeon, Young Jae
    • Journal of Life Science
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    • v.25 no.11
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    • pp.1290-1297
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    • 2015
  • Studies of the inactivation of a gene encoding pyruvate decarboxylase, pdc, in an ethanol-producing bacterium, Zymomonas mobilis, identified a mutant strain with 50% reduced PDC activity. To evaluate the possibility of a carbon-flux shift from an ethanol pathway toward higher value fermentation products, including pyruvate, succinate, and lactate, fermentation studies were carried out. Despite attempts to silence pdc expression in the wild-type strain ZM4 using cat-inserted pdc and pdc-deleted homologs by electroporation, the strain isolated showed partial gene activation. Fermentation experiments with the PDC mutant strain showed that the reduced expression level of PDC activity resulted in decreased rates of substrate uptake and ethanol production, together with increased pyruvate accumulation of 2.5 g l-1 , although lactate and succinate concentrations were not significantly enhanced in these modified strains. Despite numerous attempts, no strains were isolated in which complete pdc inactivation occurred. This result indicates that the ethanol fermentation pathway of this bacterium is totally dependent on the activity of the PDC enzyme. To ensure a redox balance of intracellular NAD and NADH levels, other enzymes, such as lactate dehydrogenase for lactate, and enzymes involved in the production of succinic acid, such as pyruvate dehydrogenase (PDH) and malic enzymes, may be needed for their increased end-product production.

Apoptosis Induction by Methanol Extract of Prunus mume Fruits in Human Leukemia U937 Cells (인체 백혈병세포에서 매실 추출물에 의한 apoptosis 유도)

  • Chung, You-Jeong;Park, Cheol;Jeong, Yong-Kee;Choi, Yung-Hyun
    • Journal of Life Science
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    • v.21 no.8
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    • pp.1109-1119
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    • 2011
  • In the present study, the pro-apoptotic effects of methanol extract of Prunus mume fruits (MEPM) in human leukemia U937 cells were investigated. It was found that exposure to MEPM resulted in growth inhibition in a concentration-dependent manner by inducing apoptosis. The induction of apoptotic cell death in U937 cells by MEPM was correlated with a down-regulation of inhibitor of apoptosis protein (IAP) family, such as X-linked inhibitor of apoptosis protein (XIAP) and survivin, anti-apoptotic Bcl-2, up-regulation of FasL and cleavage of Bid. MEPM treatment also induced the proteolytic activation of caspase-3, caspase-8 and caspase-9, and degradation of caspase-3 substrate proteins, such as poly (ADP-ribose) polymerase (PARP) and ${\beta}$-catenin. In addition, apoptotic cell death induced by MEPM was significantly inhibited by z-DEVD-fmk, a caspase-3 specific inhibitor, which demonstrates the important role of caspase-3 in the apoptotic process by MEPM in U937 cells. Taken together, these findings suggest that P. mume extracts may be a potential chemotherapeutic agent for the control of human leukemia cells and further studies will be needed to identify the active compounds.

Environmental effects in the stellar populations of Compact Elliptical galaxies

  • Kim, Suk;Jeong, Hyunjin;Lee, Youngdae;Joo, Seok-Joo;Lee, Jaehyun;Sung, Eon-Chang
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.1
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    • pp.30.2-31
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    • 2017
  • Compact elliptical (cE) galaxies are in a rare class of stellar systems characterized by high stellar densities, small sizes, high velocity dispersion, and high metallicity corresponding to elliptical galaxies. cE galaxies have been observed around massive galaxies, so they could be formed under strong influences of tidal stripping and truncation. However, the recent discovery of isolated cE galaxies requires the need of new formation scenarios. We aim at finding cE galaxies in various environments using SDSS DR12, and studying stellar population of cEs as function of environments. Based on the typical properties of cE galaxies, we selected cE candidates by restricting that low-luminosity Mg > 19.5 mag, small sizes Re < 700 pc, and high velocity dispersions ${\sigma}$ > $60kms^{-1}$. Since effect radii of cE candidates are mostly smaller than the seeing size of SDSS photometry, we calculated the effective radius by fitting a Sersic profile. In addition, we assumed that host galaxies have brightness with Mr < -21 mag, and an environmental parameter is computed as distances between cE galaxies and host-galaxies. We found 112 cE galaxies at z < 0.05, which have high sersic indices (mean value is 5.2) similar to the typical massive elliptical galaxies. Mgb values of cE galaxies increase as the distances from the host galaxies decrease. Especially, for cEs close to the host galaxies (NcE; $D_{host}$ < 300 pc), the Mgb values are similar to those of massive elliptical galaxies, which is consistent with the previous studies. On the other hand, cE galaxies distant from the host galaxies (DcE; Dhost >300 pc) have lower Mgb values than the conventional cE. The Mgb values follow the ${\sigma}$-Mgb relation of elliptical galaxies, and are connected to its faint end. This can be explained as a result of different merger histories for differing environments. For example, NcE galaxies are formed by tidal stripping by massive galaxies as suggested by previous studies, but DcE galaxies could be linked with high-redshift spheroids (e.g. red nuggets) which have not evolved into present-day elliptical galaxies because of the environmental influences.

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Effect of liners and primers on tensile bond strength between zirconia and resin-based luting agent

  • Jo, Eun-Hye;Huh, Yoon-Hyuk;Ko, Kyung-Ho;Park, Chan-Jin;Cho, Lee-Ra
    • The Journal of Advanced Prosthodontics
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    • v.10 no.5
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    • pp.374-380
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    • 2018
  • PURPOSE. The effect of silica-based glass-ceramic liners on the tensile bond strength between zirconia and resin-based luting agent was evaluated and compared with the effect of 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primers. MATERIALS AND METHODS. Titanium abutments and zirconia crowns (n = 60) were fabricated, and the adhesive surfaces of the specimens were treated by airborne-particle abrasion. The specimens were divided into 5 groups based on surface treatment: a control group, 2 primer groups (MP: Monobond Plus; ZP: Z Prime Plus), and 2 liner groups (PL: P-containing Liner; PFL: P-free Liner). All specimens were cemented with self-adhesive resin-based luting agent. After 24-hour water storage and thermocycling (5,000 cycles, $5^{\circ}C/55^{\circ}C$), the tensile bond strength was measured using a universal testing machine. Failure mode analysis and elemental analysis on the bonding interface were performed. The data were analyzed using Kruskal-Wallis test, Dunn's post hoc test, and Fisher's exact test. RESULTS. The liner groups and primer groups showed significantly higher tensile bond strengths than that of the control group (P<.05). PFL showed a significantly higher tensile bond strength than the primer groups (P<.05). The percentage of mixed failure was higher in the primer groups than in the control group (P<.001), and all the specimens showed mixed failure in the liner groups (P<.001). A chemical reaction area was observed at the bonding interface between zirconia and liner. CONCLUSION. The application of liner significantly increased the tensile bond strength between zirconia and resin-based luting agent. PFL was more effective than MDP-containing primers in improving the tensile bond strength with the resin-based luting agent.

Genetic Contribution of Indigenous Yakutian Cattle to Two Hybrid Populations, Revealed by Microsatellite Variation

  • Li, M.H.;Nogovitsina, E.;Ivanova, Z.;Erhardt, G.;Vilkki, J.;Popov, R.;Ammosov, I.;Kiselyova, T.;Kantanen, J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.5
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    • pp.613-619
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    • 2005
  • Indigenous Yakutian cattle' adaptation to the hardest subarctic conditions makes them a valuable genetic resource for cattle breeding in the Siberian area. Since early last century, crossbreeding between native Yakutian cattle and imported Simmental and Kholmogory breeds has been widely adopted. In this study, variations at 22 polymorphic microsatellite loci in 5 populations of Yakutian, Kholmogory, Simmental, Yakutian-Kholmogory and Yakutian-Simmental cattle were analysed to estimate the genetic contribution of Yakutian cattle to the two hybrid populations. Three statistical approaches were used: the weighted least-squares (WLS) method which considers all allele frequencies; a recently developed implementation of a Markov chain Monte Carlo (MCMC) method called likelihood-based estimation of admixture (LEA); and a model-based Bayesian admixture analysis method (STRUCTURE). At population-level admixture analyses, the estimate based on the LEA was consistent with that obtained by the WLS method. Both methods showed that the genetic contribution of the indigenous Yakutian cattle in Yakutian-Kholmogory was small (9.6% by the LEA and 14.2% by the WLS method). In the Yakutian-Simmental population, the genetic contribution of the indigenous Yakutian cattle was considerably higher (62.8% by the LEA and 56.9% by the WLS method). Individual-level admixture analyses using STRUCTURE proved to be more informative than the multidimensional scaling analysis (MDSA) based on individual-based genetic distances. Of the 9 Yakutian-Simmental animals studied, 8 showed admixed origin, whereas of the 14 studied Yakutian-Kholmogory animals only 2 showed Yakutian ancestry (>5%). The mean posterior distributions of individual admixture coefficient (q) varied greatly among the samples in both hybrid populations. This study revealed a minor existing contribution of the Yakutian cattle in the Yakutian-Kholmogory hybrid population, but in the Yakutian-Simmental hybrid population, a major genetic contribution of the Yakutian cattle was seen. The results reflect the different crossbreeding patterns used in the development of the two hybrid populations. Additionally, molecular evidence for differences among individual admixture proportions was seen in both hybrid populations, resulting from the stochastic process in crossing over generations.

Surface Elevation Recovery Methods from Pressure Gage for Irregular Waves (불규칙파(不規則波에) 대한 압력식(壓力式) 파고계(波高計)의 적용성(適用性)에 관한 연구(研究))

  • Kwon, Jung Gon;Kang, Ju Bok
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.4_1
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    • pp.129-136
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    • 1992
  • A precedure for recovering surface displacement from a time series of pressure measured by a pressure gage in a shallow water (that is, FFTM, LCM. IWM) is investigated with respect to a proper cut-off-frequency of a frequency response function for the accurate recovery of wave height and period. The authors examined the applicability of above mentioned three transformation procedures through field observations and laboratory experiments and the following results are obtained. i) The cut-off-frequency of the frequency response function used in FFTM is deeply depend on both the frequency response of the pressure sensor and the water depth at the sensor. In this study, a relatively accurate surface displacement can be recovered when the frequency response function is cut off at the frequency corresponding to kh=3.0 where k is a wave number at the depth of h. The frequency response function in the region higher than the cut-off-frequency is set constant to be the value at the cut-off-frequency. ii) The transformed surface displacements by LCM are affected by the small waves of short periods included in the measured pressure. It is found that pressure variation whose local frequency is higher than kh=1.5 has to be neglected to recover surface displacement sufficiently. iii) In IWM, the linear pressure response function is usually utilized by multiplying a coefficient N which is a function of the frequency (or kh) and takes a value around unity. However, in this study, a constant value of N(=1.0) gives a relatively accurate recovery of surface displacements.

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Association of the A-G Polymorphism in Porcine Adiponectin Gene with Fat Deposition and Carcass Traits

  • Dai, L.H.;Xiong, Y.Z.;Deng, C.Y.;Jiang, S.W.;Zuo, B.;Zheng, R.;Li, F.E.;Lei, M.G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.6
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    • pp.779-783
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    • 2006
  • The adiponectin gene is known to be involved in the regulation of energy homeostasis involving food intake, carbohydrate and lipid metabolism. Human adiponectin gene polymorphisms have been recently reported to be associated with obesity, insulin sensitivity and the risk of type 2 diabetes. The present study was carried out to investigate the porcine adiponectin gene as a candidate gene for fat deposition and carcass traits. A mutation of A178G of the porcine adiponectin gene that resulted in substitution of the amino acid Isoleucine to Valine was identified. AcyI PCR-RFLP was used to detect the polymorphism of the genotypes in five different pig populations (Large White, Landrace, Duroc, Chinese breeds Meishan and Qingping). The A allele frequency was significantly higher among subjects from Chinsese lard type breeds, while the G allele was the only one present in those from Western lean type breeds. To determine if there was an association of the polymorphism with phenotypic variation, the mutation was tested in 267 pigs of the "Large $White{\times}Meishan$" F2 resource population. The results of association analyses showed significant associations of the genotypes with fat deposition and carcass traits. Allele G was significantly associated with increase in loin eye height, loin eye area and lean meat percentage and bone percentage, and decrease in fat mean percentage, ratio of lean to fat, shoulder fat thickness, 6-7 rib fat thickness, thorax-waist fat thickness and buttock fat thickness. The substitution of A178G (Ile60Val) happened to be located at amino acid 60 in the collagenous domain of porcine adiponectin which might affect the association into higher-order structures, and accordingly affect the posttranslational modifications and optimal biological activity of the multimeric forms. The identified functional polymorphism provides new evidence of adiponectin as an important candidate gene affecting fat deposition and carcass traits in pigs.

Prognostic Significance of Preoperative Serum Alpha-fetoprotein in Hepatocellular Carcinoma and Correlation with Clinicopathological Factors: a Single-center Experience from China

  • An, Song-Lin;Xiao, Ting;Wang, Li-Ming;Rong, Wei-Qi;Wu, Fan;Feng, Li;Liu, Fa-Qiang;Tian, Fei;Wu, Jian-Xiong
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.10
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    • pp.4421-4427
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    • 2015
  • Objectives: To investigate the prognosis significance of preoperative serum alpha-fetoprotein (AFP) and the correlation with clinicopathological factors of hepatocellular carcinoma (HCC) patients who underwent hepatectomy. Materials and Methods: Clinicopathological data of retrospective analysis were collected for 251 HCC patients undergoing hepatectomy in this study. According to preoperative AFP level, patients were categorized into AFP-negative (0-20ng/mL) and AFP-positive (>20 ng/mL) groups for Kaplan-Meier analysis and Cox proportional hazard regression modeling. Results: The results demonstrated that increased AFP was associated with longer prothrombin time (PTs), liver capsule invasion, low grade differentiation, and late Barcelona Clinic Liver Center (BCLC) stage. Moreover, the female patients had a greater prevalence of increased preoperative AFP than male patients [284.8 (3.975-3167.5) vs (3.653-140.65); Z-2.895, p=0.004]. The 1-, 3-, and 5-year recurrence-free survival (RFS) rates were 78.1, 57.5, and 40.6 % in the AFP-negative group and 61.8, 37.7, and 31.4 %, respectively, in the AFP-positive group (log-rank test 8.312, p=0.004). The 1-, 3-, and 5-year overall survival (OS) rates were 94.4, 83.8, and 62.3% in the AFP-negative group and 87.2, 60.0, and 36.7%, respectively, in the AFP-positive group. The difference was statistically significant (log-rank test, 16.884, p=0.000). Cox proportional-hazards model identified preoperative AFP to be an independent prognostic predictor of overall survival. Conclusions: Preoperative serum AFP is an independent predictor of prognosis among HCC patients following surgical resection. Female patients have a higher preoperative AFP than their male counterparts.

Physico-chemical Characteristics of Submicron Aerosol at West Inflow Regions in the Korean Peninsula III. Physical-Chemical Behavior and Long-range Transport of PM1 (한반도 서부유입권역에서 대기 중 에어로졸 성분의 물리·화학적 특성 연구 III. 화학적 거동 및 장거리 이동)

  • Park, Taehyun;Ahn, Junyoung;Choi, Jinsoo;Lim, Yongjae;Park, Jinsoo;Kim, Jeongho;Oh, Jun;Lee, Yonghwan;Hong, Youdeog;Hong, Jihyung;Choi, Yongjoo;Lee, Taehyoung
    • Journal of Korean Society for Atmospheric Environment
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    • v.33 no.2
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    • pp.124-138
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    • 2017
  • Physico-chemical measurement of non-refractory submicron particles($NR-PM_1$) was conducted in Baengnyeong Island, Korea using Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) from 2012 to 2014. Organics and ammoniated sulfate were dominant species in $NR-PM_1$. The organics was found to have similar fractions(approximate 40%) of $NR-PM_1$ during the summer and winter, while the sulfate fractions of $NR-PM_1$ were calculated to be approximately 47% and 31% for the summer and winter, respectively, suggesting the possibility that particles provide non-acidic surfaces for condensation of nitric acid in the winter. The nitrate fractions of approximate 4% and 20% of $NR-PM_1$ were observed in August (summer) and November (winter), respectively, resulting that the relatively low concentration of sulfate in $NR-PM_1$ provided a non-acidic surface for nitric acid condensation and formation of particulate ammoniated nitrate is favored thermodynamically in winter. The new particle formation (NPF) event and particle growth rate were analyzed for each month in 2014 using Scanning Mobility Particle Sizer(SMPS). The Percent of NPF events was the highest in winter, but NPF event was not observed during summer due to relatively high temperature and frequent rainfall. The average particle growth rate was 3.5 nm/h and the highest particle growth rate was 5.5 nm/h in May. We observed the long-range transport of the anthropogenic sulfate from the East Asia during the intensive monitoring period of November between Qingdao and Baengnyeong Island in 2013. The relatively high concentrations of m/z 60 measured in HR-ToF-AMS was observed in May and June at Baengnyeong Island, suggesting the possibility of the influence of biomass burning from the East Asia to the Korean Peninsula.

Crown Shape Control of Pinus koraiensis S et. Z. (III) - Crown Shape Types for Seed and Timber Production from the Trees under Age Class III - (잣나무의 수형(樹型) 조절(調節) (III) - III영급(齡級) 이하(以下) 인공림(人工林)에서 잣과 목재(木材) 생산(生産)을 위한 수형(樹型) -)

  • Yi, Jae-Seon;Song, Jeong-Ho;Park, Moon-Han;Han, Sang-Urk
    • Journal of Korean Society of Forest Science
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    • v.88 no.2
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    • pp.195-204
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    • 1999
  • To improve nut production and timber quality in a plantation, crown shape controls were suggested for Korean white pines (Pinus koraiensis) under age class III through the analyses of the crown shape controls for seed orchard trees in several species, of crown status of controlled and uncontrolled trees in a Korean white pine seed orchard, and of growth characteristics of plantation trees under age class III. For nut production from the small trees less than 8 m, modified leader type can be applied by cutting the central leader and all branches below 1 m and keeping 4~5 nodes with 3~4 whorled branches a node locating 1 m apart. Trees with a 4~8 m long trunk below the first living branch are shaped into trees for nut and timber production, which have a 4~8 m long knotless stem and a modified leader type crown with 4~5 nodes with 3~4 whorled branches a node at a distance of 1 m. Trees, showing the first living branch at or above 9 m from the surface, are pruned severely for timber production and result in a central leader type containing two fifths of the initial crown. It is advisable to remove the leader and the branches when collecting cones or after/during October to take advantage of easy labor and little resin while cutting. After stem cut, branches showing apical dominance are to be cut to control height when necessary. The removal of the uppermost node may be needed to control the crown shape several years after the initial stem-cut.

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