Simulation of single grid-based phase-contrast x-ray imaging (g-PCXI)

Lim, H.W.,Lee, H.W.,Cho, H.S.,Je, U.K.,Park, C.K.,Kim, K.S.,Kim, G.A.,Park, S.Y.,Lee, D.Y.,Park, Y.O.,Woo, T.H.,Lee, S.H.,Chung, W.H.,Kim, J.W.,Kim, J.G. Elsevier BV * North-Holland 2017 Nuclear Instruments & Methods in Physics Research. Vol. No.

<P><B>Abstract</B></P> <P>Single grid-based phase-contrast x-ray imaging (g-PCXI) technique, which was recently proposed by Wen et al. to retrieve absorption, scattering, and phase-gradient images from the raw image of the examined object, seems a practical method for phase-contrast imaging with great simplicity and minimal requirements on the setup alignment. In this work, we developed a useful simulation platform for g-PCXI and performed a simulation to demonstrate its viability. We also established a table-top setup for g-PCXI which consists of a focused-linear grid (200-lines/in strip density), an x-ray tube (100-μm focal spot size), and a flat-panel detector (48-μm pixel size) and performed a preliminary experiment with some samples to show the performance of the simulation platform. We successfully obtained phase-contrast x-ray images of much enhanced contrast from both the simulation and experiment and the simulated contract seemed similar to the experimental contrast, which shows the performance of the developed simulation platform. We expect that the simulation platform will be useful for designing an optimal g-PCXI system.</P> <P><B>Highlights</B></P> <P> <UL> <LI> It is proposed for the single grid-based phase-contrast x-ray imaging (g-PCXI) technique. </LI> <LI> We implemented for a numerical simulation code. </LI> <LI> The preliminary experiment with several samples to compare is performed. </LI> <LI> It is expected to be useful to design an optimal g-PCXI system. </LI> </UL> </P>

200 GeV/핵자 유황이온과 핵건판핵의 충돌에 의해 생성된 헬륨 파쇄핵의 극한파쇄 연구

김동철,송진섭,윤천실,정성헌,박인곤,김종오,김철수,김태연,이승희,조재희,천병구,김재률,김준원,김태익,박명렬,장한일,임인택 慶尙大學校 기초과학연구소 1992 基礎科學硏究所報 Vol.8 No.-

고에너지 중이온 원자핵과 핵건판의 충돌에서, 200GeV/핵자 유황이온에 의해 생성된 파쇄 헬륨핵(Z=2)의 실험실계의 방출각 분포는 표적핵에 무관한 회귀공식. dN=exp[a+k exp(η-y_b)]d[exp(η-y_b)]로 잘 표현된다. 여기에서 의사신속도 η=-ln[tan(θ/2)]이고, y_b는 실험실계의 입사입자(^32S)의 신속도이다. 이 공식에 의한 적합에서 k=-0.057±0.008로 얻어진다. 즉, 핵건판과 고에너지 중이온의 충돌에서 파쇄 헬륨핵의 exp(η-y_b)의 분포는 "극한파쇄" 현상을 잘 설명하고 있다. The angular distribution of emission angle θ of helium (Z=2) produced in the collisions of incident particles of 200 GeV/nucleon ^32S in nuclear emulsion is well expressed by dN=exp[a+k exp(η-y_b)]d[exp(η-y_b)] where the pseudorapidity is η=-ln[tan(θ/2)], the laboratory system primary rapidity is y_b, and k=-0.057+0.008. The shape of this frequency of occurrence distributions in terms of exp(η-y_b) attests to the validity of the concept of "limiting fragmentation" for helium projectile fragments produced in the projectile fragmentation regions of heavy ion collisions in nuclear emulsion.

The LIM-only transcription factor LMO2 determines tumorigenic and angiogenic traits in glioma stem cells

Kim, S-H,Kim, E-J,Hitomi, M,Oh, S-Y,Jin, X,Jeon, H-M,Beck, S,Jin, X,Kim, J-K,Park, C G,Chang, S-Y,Yin, J,Kim, T,Jeon, Y-j,Song, J,Lim, Y C,Lathia, J D,Nakano, I,Kim, H Macmillan Publishers Limited 2015 CELL DEATH AND DIFFERENTIATION Vol.22 No.9

Glioblastomas (GBMs) maintain their cellular heterogeneity with glioma stem cells (GSCs) producing a variety of tumor cell types. Here we interrogated the oncogenic roles of Lim domain only 2 (LMO2) in GBM and GSCs in mice and human. High expression of LMO2 was found in human patient-derived GSCs compared with the differentiated progeny cells. LMO2 is required for GSC proliferation both in vitro and in vivo, as shRNA-mediated LMO2 silencing attenuated tumor growth derived from human GSCs. Further, LMO2 is sufficient to induce stem cell characteristics (stemness) in mouse premalignant astrocytes, as forced LMO2 expression facilitated in vitro and in vivo growth of astrocytes derived from Ink4a/Arf null mice and acquisition of GSC phenotypes. A subset of mouse and human GSCs converted into vascular endothelial-like tumor cells both in vitro and in vivo, which phenotype was attenuated by LMO2 silencing and promoted by LMO2 overexpression. Mechanistically, the action of LMO2 for induction of glioma stemness is mediated by transcriptional regulation of Jagged1 resulting in activation of the Notch pathway, whereas LMO2 directly occupies the promoter regions of the VE-cadherin gene for a gain of endothelial cellular phenotype. Subsequently, selective ablation of human GSC-derived VE-cadherin-expressing cells attenuated vascular formation in mouse intracranial tumors, thereby significantly prolonging mouse survival. Clinically, LMO2 expression was elevated in GBM tissues and inversely correlated with prognosis of GBM patients. Taken together, our findings describe novel dual roles of LMO2 to induce tumorigenesis and angiogenesis, and provide potential therapeutic targets in GBMs.

Effects of Organic or Inorganic Acid Supplementation on Growth Performance, Nutrient Digestibility and White Blood Cell Counts in Weanling Pigs

D. Y. Kil,L. G. Piao,H. F. Long,J. S. Lim,M. S. Yun,C. S. Kong,W. S. Ju,H. B. Lee,Y. Y. Kim 아세아·태평양축산학회 2006 Animal Bioscience Vol.19 No.2

Four experiments were conducted to investigate the effect of organic or inorganic acid supplementation on the growth performance, nutrient digestibility, intestinal measurements and white blood cell counts of weanling pigs. In growth trial (Exp I), a total of 100 crossbred pigs ({Landrace횞Yorkshire}횞Duroc), weaned at 23짹2 days of age and 7.25짹0.10 kg average initial body weight (BW), were allotted to 5 treatments by body weight and sex in a randomized complete block (RCB) design. Three different organic acids (fumaric [FUA], formic [FOA] or lactic acid [LAA]) and one inorganic acid (hydrochloric acid [SHA]) were supplemented to each treatment diet. Each treatment had 5 replicates with 4 pigs per pen. During 0-3 wk, average daily gain (ADG), average daily feed intake (ADFI) and feed efficiency (G/F ratio) were not significantly different among treatments. However, pigs fed LAA or SHA diet showed improved ADG by 15 or 13% respectively and 12% greater ADFI in both treatments compared to CON diets. Moreover, compared to organic acid treatments, better ADG (p = 0.07) and ADFI (p = 0.09) were observed in SHA diet compared to pigs that were fed the diet containing organic acids (FUA, FOA or LAA). However, during 4-5 wk, no differences in ADG, ADFI and G/F ratio were observed among treatments. Overall, ADG, ADFI and G/F ratio were not affected by acidifier supplementation. Although it showed no significant difference, pigs fed LAA or SHA diets showed numerically higher ADG and ADFI than pigs fed other treatments. In metabolic trial (Exp II), 15 pigs were used to evaluate the effect of acidifier supplementation on nutrient digestibility. The digestibility of dry matter (DM), crude protein (CP), crude fat (CF), crude ash (CA), calcium (Ca) and phosphorus (P) was not improved by acidifier supplementation. Although the amount of fecal-N excretion was not different among treatments, that of urinary-N excretion was reduced in acidsupplemented treatments compared to CON group (p = 0.12). Subsequently, N retention was improved in acid-supplemented groups (p = 0.17). In anatomical trial (Exp III), the pH and Cl- concentrations of digesta in gastrointestinal (GI) tracts were not affected by acidifier supplementation. No detrimental effect of intestinal and lingual (taste bud) morphology was observed by acidifier supplementation particularly in inorganic acid treatment. In white blood cell assay (Exp IV), 45 pigs were used for measuring white blood cell (WBC) counts. In all pigs after LPS injection, WBC counts had slightly declined at 2 h and kept elevating at 8 h, then returned to baseline by 24 h after injection of lipopolysaccharide (LPS). However, overall WBC counts were not affected by acidifier supplementation. In conclusion, there was no difference between organic and inorganic acidifier supplementation in weanling pigs' diet, however inorganic acidifier might have a beneficial effect on growth performance and N utilization with lower supplementation levels. Furthermore, inorganic acidifier had no negative effect on intestinal measurements and white blood cell counts in weanling pigs. These results suggested that inorganic acidifier might be a good alternative to organic acidifiers in weanling pigs.

Five-year clinical outcomes in patients with significant coronary artery spasm: A propensity score-matched analysis

Choi, B.G.,Park, S.H.,Rha, S.W.,Park, J.Y.,Choi, S.Y.,Park, Y.,Xu, S.,Ngow, H.A.,Ali, J.,Li, H.,Kim, J.B.,Lee, S.,Na, J.O.,Choi, C.U.,Lim, H.E.,Kim, J.W.,Kim, E.J.,Park, C.G.,Seo, H.S.,Oh, D.J. Elsevier/North-Holland Biomedical Press 2015 INTERNATIONAL JOURNAL OF CARDIOLOGY Vol.184 No.-

Background: Coronary artery spasm (CAS) is known to be a risk factor of acute coronary syndrome and angina pectoris. However, there is no currently available data with larger study population regarding long-term clinical outcomes of CAS in real world clinical practice. Objectives: We evaluated the prevalence of CAS and the impact of CAS on 5-year clinical outcomes in a series of Asian CAS patients documented by intracoronary acetylcholine (Ach) provocation test. Methods: A total of 1413 consecutive patients without significant coronary artery disease (CAD) who underwent Ach provocation test between Nov. 2004 and Oct. 2008 were enrolled. Significant CAS was defined as >70% of narrowing by incremental intracoronary injection of 20, 50 and 100μg. Patients were divided into two groups based on the presence of significant CAS (the non-CAS group: n=640, the CAS group; n=773). To adjust potential confounders, a propensity score matched (PSM) analysis was performed using the logistic regression model. Results: A total of 54.7% (773/1413) patients were diagnosed as CAS documented by Ach provocation test. After PSM analysis, 2 propensity-matched groups (451 pairs, n=902, C-statistic=0.677) were generated. Despite of similar incidence of individual hard endpoints including mortality, myocardial infarction and revascularization, the CAS group showed the higher trend of recurrent angina requiring follow up angiography than the non-CAS group up to 5years (HR; 1.56, 95% C.I.; 0.99-2.46, p=0.054). Conclusions: The prevalence of CAS was 54.7%. Although the cumulative incidence of recurrent angina requiring follow up coronary angiography seems to be increased up to 5years in CAS patients, CAS patients was not associated with major individual and composite clinical outcomes such as mortality, MI, PCI, CVA with optimal medical therapy as compared with patients without CAS.

Letter to the Editor: Neuropathy, Ataxia, Retinitis Pigmentosa-like Phenotype Associated with a Mitochondrial G8363A Mutation in a Family

Kim, S. Y.,Han, J. Y.,Kim, H. A.,Lim, B. C.,Seo, J. E.,Choi, M.,Kim, K. J.,Lee, I. G.,Chae, J.-H. INSTITUTE FOR CLINICAL SCIENCE 2018 Annals of clinical and laboratory science Vol.48 No.4

Synthesis of 14-π nickel(Ⅱ) complexes with disubstituted benzoN₄macrocycles and electrochemical studies of 14-π nickel(Ⅱ) complexes with monosubstituted benzoN₄ macrocycles

Na, H.G.,Lee, D.C.,Lim, J.W.,Choi, J.H.,Byun, J.C.,Park, Y.C. 濟州大學校 基礎科學硏究所 2002 基礎科學硏究 Vol.15 No.2

The template reaction of a 1: 1 mixture of 4,5-disubstituted(2CH_(3) or 2C1)-1,2-phenylenediamine and alkylenediamine [NH_(2)- (CH_(2))_(n)-NH_(2); n = 2 or 3] with 2,4-pentanedione in the presence of a nickel(Ⅱ) salt gave a series of asymmetric 14-11 nickel(Ⅱ) complexes with disubstituted tetraazaannulene, [Ni(Me_(4)-X_(2)bzotetraaza[Y]ene] (X =CH_(3) and Cl, Y= 14 and 15), which were characterized by mass, infrared, ^(1)H and ^(13)C NMR spectra. The electronic effects of the disubstituent groups on the phenyl ring significantly affected the spectral properties of the complexes. The electrochemical behaviors of the nickel(Ⅱ) complexes with monosubstituted benzoN_(4) macrocycles, [Ni(Me_(4)-Xbzotetraaza[Ylene)] (X = H, NO_(3), CH3 and Cl, Y = 14 and 15) exhibited cyclic voltammograms characterized by, two irreversible, one electron, waves due to oxidation of the macrocycle (Mc); Mc^(+) → Mc^(2+) in the ranges of +0.06-+0.28 V for 14-X and t-0.01-+0.29 V for 15-X, and Mc^(+) → Mc^(2+) in the ranges of +0.58 to + 0.81V for 14-X and +0.36 to +0.79 V for 15-X versus Ag/Ag^(+) (0.01 M AgNO_(3) in 0.1 M tetraethylammonium perchlorate (TEAP) acetonitrile solution). In the reduction area only one reversible wave Ni^(2+)/Ni^(+) was detected at E_(1/2)= -1.65 to -2.65 V in DMSO. The relationships between the oxidation potentials (E_(ap) and σ_(p) were linear with a slopes of 0.23 V for 14-X and 0.18 or 0.23 V for 15-X (correlation coefficients of 0.99). The catalytic reduction of dioxygen by the electropolyrnerized glassy carhon electrodes (GCE) occurred at about 400 mV more positive than by the bared one. The catalytic reduction using 14-X occurred at potentials somewhat more positive than using 15-X.

Complete genome sequence of Bacillus velezensis G341, a strain with a broad inhibitory spectrum against plant pathogens

Lee, H.H.,Park, J.,Lim, J.Y.,Kim, H.,Choi, G.J.,Kim, J.C.,Seo, Y.S. Elsevier Science Publishers 2015 Journal of biotechnology Vol.211 No.-

Bacillus velezensis G341 can suppress plant pathogens by producing antagonistic active compounds including bacillomycin D, fengycin, and (oxy) difficidin. The complete genome sequence of this bacterium was characterized by one circular chromosome of 4,009,746bp with 3953 open reading frames. The genome contained 36 pseudogenes, 30 rRNA operons, and 95 tRNAs. This complete genome sequence provides an additional resource for the development of antimicrobial compounds.

지속적인 생균제의 첨가가 돼지의 성장, 영양소 이용율 혈중 요소태 질소 및 면역능력에 미치는 영향

길동용,임종선,전경철,김법균,김경수,김유용 한국동물자원과학회 2004 한국축산학회지 Vol.46 No.1

This experiment was conducted to investigate the effect of continuous feeding of probiotics on growth performance, nutrient digestibility, blood urea nitrogen(BUN) and immune responses in pigs. Treatments were 1) Control(basal diet), 2) P-0.1(basal diet + 0.1% probiotics) and 3) P-0.2(basal diet + 0.2% probiotics). In growth trial, a total of sixty pigs(6.17±0.45 ㎏ average body weight) weaned at 21 days of age were used. All pigs were assigned according to sex and body weight, and each treatment had 5 replicates of 4 pigs per pen in a randomized complete block(RCB) design. During 0~8 weeks, there was no significant difference in average daily gain(ADG), average daily feed intake(ADFI) and gain:feed ratio(G/F) among treatments. During 9~20 weeks, ADG was improved significantly in pigs fed P-0.1 or P-0.2 diets when compared to the pig fed control diet(P<0.05), but there was no significant difference in ADFI and G/F ratio. During overall period, ADG, ADFI and G/F ratio were not significantly different among treatments. In the first metabolic trial(17.93±1.45㎏ average body weight), apparent digestibility of DM, protein, fat in pigs fed P-0.1 and P-0.2 diets were greater than in pigs fed control diet(P<0.05) and ash digestibility in pigs fed P-0.2 diet was significantly higher than in pigs fed control diet(P<0.05). Calcium digestibility in pigs fed P-0.2 diet was significantly higher than in pigs fed control and P-0.1 diets(P<0.05). Fecal-N excretion was lower in pigs fed P-0.1 and P-0.2 diets than in pigs fed control(P<0.05). In the second metabolic trial(41.80±2.68㎏ average body weight), there was no significant difference among treatments in apparent digestibility of nutrients and N-retention. In blood assay for the BUN and immune responses investigations, there was no significant difference among treatments during overall period of experiment. Therefore, this experiment suggested that probiotics supplementation could improve growth performance and nutrient digestibility of pigs.

Roles of 14-3-3η in mitotic progression and its potential use as a therapeutic target for cancers

Lee, C G,Park, G-Y,Han, Y K,Lee, J H,Chun, S H,Park, H-Y,Lim, K-H,Kim, E-G,Choi, Y-J,Yang, K,Lee, C-W Macmillan Publishers Limited 2013 Oncogene Vol.32 No.12

14-3-3 proteins are involved in several cellular processes, including the G1/S and G2/M cell cycle transitions. However, their roles during mitosis are not well understood. Here, we showed that depletion of 14-3-3η, a 14-3-3 protein isoform, enhanced mitotic cell death, resulting in sensitization to microtubule inhibitors and inhibition of aneuploidy formation. The enhanced mitotic cell death by depletion of 14-3-3η appeared to be both caspase-dependent and independent. Furthermore, enhanced mitotic cell death and a reduction in aneuploidy following 14-3-3η depletion were independent of the mitotic checkpoint, which is thought to be the primary signaling event in the regulation of the cell death induced by microtubule inhibitors. When 14-3-3η depletion was combined with microtubule inhibitors in HCT116 and U87MG cells, it sensitized both cancer cell lines to microtubule inhibitors. These results collectively suggest that 14-3-3η may be required for mitotic progression and may be considered as a novel anti-cancer strategy in combination with microtubule inhibitors.