Neuroprotective Effect of Human Adipose Stem Cell-Derived Extract in Amyotrophic Lateral Sclerosis

Jeon, G. S.,Im, W.,Shim, Y. M.,Lee, M.,Kim, M. J.,Hong, Y. H.,Seong, S. Y.,Kim, M.,Sung, J. J. Springer Science + Business Media 2016 Neurochem Res Vol.41 No.4

<P>Amyotrophic lateral sclerosis (ALS) is a devastating human neurodegenerative disease. The precise pathogenic mechanisms of the disease remain uncertain, and as of yet, there is no effective cure. Human adipose stem cells (hASC) can be easily obtained during operative procedures. hASC have a clinically feasible potential to treat neurodegenerative disorders, since cytosolic extract of hASC contain a number of essential neurotrophic factors. In this study, we investigated effects of hASC extract on the SOD1 G93A mouse model of ALS and in vitro test. Administration of hASC extract improved motor function and prolonged the time until symptom onset, rotarod failure, and death in ALS mice. In the hASC extracts group, choline acetyltransferase immunostaining in the ventral horn of the lumbar spinal cord showed a large number of motor neurons, suggesting normal morphology. The neuroprotective effect of hASC extract in ALS mice was also suggested by western blot analysis of spinal cord extract from ALS mice and in vitro test. hASC extract treatment significantly increased expression of p-Akt, p-CREB, and PGC-1 alpha in SOD1 G93A mouse model and in vitro test. Our results indicated that hASC extract reduced apoptotic cell death and recovered mutant SOD1-induced mitochondrial dysfunction. Moreover, hASC extract reduced mitochondrial membrane potential. In conclusion, we have demonstrated, for the first time, that hASC extract exert a potential therapeutic action in the SOD1 G93A mouse model of ALS and in vitro test. These findings suggest that hASC hold promise as a novel therapeutic strategy for treating ALS.</P>

Structural, morphological, compositional, and optical properties of single step electrodeposited Cu₂ZnSnS₄ (CZTS) thin films for solar cell application

Lee, S.G.,Kim, J.,Woo, H.S.,Jo, Y.,Inamdar, A.I.,Pawar, S.M.,Kim, H.S.,Jung, W.,Im, H.S. Elsevier 2014 Current Applied Physics Vol.14 No.3

We fabricate a Cu<SUB>2</SUB>ZnSnS<SUB>4</SUB> (CZTS) absorber layer, by using single step electrodeposition of CZTS precursor, deposited at -1.05 V, followed by high temperature annealing in a sulfur atmosphere. X-ray diffraction pattern indicates that the as-grown sample is amorphous in nature, and polycrystalline CZTS thin films with kesterite crystal structure have been obtained by sulfurization from 450 to 580 <SUP>o</SUP>C. Surface morphologies of the as-grown sample show some voids with agglomerated particles. After sulfurization, the morphologies of the annealed samples become more uniform, and dense. EDAX study reveals that the sulfurized samples are nearly stoichiometric, being Cu-rich and S-deficient in composition. The band gaps of the annealed samples are found to be in the range from 1.9 to 1.5 eV.

Phase II study of preoperative chemoradiotherapy (CRT) with irinotecan plus S-1 in locally advanced rectal cancer

Shin, S.J.,Kim, N.K.,Keum, K.C.,Kim, H.G.,Im, J.S.,Choi, H.J.,Baik, S.H.,Choen, J.H.,Jeung, H.C.,Rha, S.Y.,Roh, J.K.,Chung, H.C.,Ahn, J.B. Elsevier Science Publishers 2010 Radiotherapy and oncology Vol.95 No.3

Background and purpose: The aim of this study is to evaluate the efficacy and safety of preoperative radiation therapy combined with S-1 and irinotecan (SI) in LARC. Materials and methods: Patients were considered LARC if they had a T3/T4 lesion or node positive. Weekly doses of 40mg/m<SUP>2</SUP> irinotecan were intravenously administered once per week during weeks 1-5 of radiotherapy. S-1 (70mg/m<SUP>2</SUP>) was given from Monday to Friday in all weeks of radiotherapy. 3-D conformal radiotherapy was given at daily fractions of 1.8Gy for 5days for a total dose of 50.4 (45+5.4)Gy. Surgery was performed 4-6weeks following the completion of chemoradiation. Results: Between June 2006 and November 2007, 43 pts were enrolled. The stage was: cT3 24 patients, cT4 6 patients; 28 patients were cN+. Forty-one patients completed the chemoradiation and 42 patients underwent operation: a low anterior resection was performed in 36 patients, a total colectomy in 1 patient, and an abdominal perineal resection in 5 patients. T downstaging was observed in 50%; 23 N+ patients became N- (55%). The complete pathological response was observed in 9 patients (21%). The 3-year locoregional failure rate, distant failure rate, disease-free survival, and overall survival were 9.5%, 18.6%, 72.1%, and 94.3%, respectively. Only three patients experienced G3 diarrhea; one had G3 sepsis and two had septic shock. Hematological toxicity (G3-G4) was observed in five patients. Conclusions: This study demonstrated the efficacy of preoperative CRT with S-1 and irinotecan with 21% of complete response. However, prompt recognition and management of infection is needed to use it in patients with locally advanced rectal cancer.

Roseovarius halotolerans sp. nov., isolated from deep seawater

Oh, Y.-S.,Lim, H.-J.,Cha, I.-T.,Im, W.-T.,Yoo, J.-S.,Kang, U. G.,Rhee, S.-K.,Roh, D.-H. Microbiology Society 2009 International journal of systematic and evolutiona Vol.59 No.11

<P>A Gram-reaction-negative, non-motile, aerobic bacterium, designated HJ50(T), was isolated from deep seawater of the East Sea, South Korea. Cells were ovoid to rod-shaped (0.5-0.8x1.3-3.0 mum), often with unequal ends, suggesting a budding mode of reproduction. The strain had an absolute requirement for sea salts and tolerated up to 20 % (w/v) sea salts. Propionate, dl-lactate, 2-ketogluconate, 3-hydroxybutyrate and rhamnose were used as growth substrates, but not mannitol, salicin, 4-hydroxybenzoate or acetate. The major fatty acid was summed feature 7 (C(18 : 1)omega7c/omega9t/omega12t) and the DNA G+C content was 59.0+/-0.1 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed that this strain was affiliated with the genus Roseovarius. Similarities between the 16S rRNA gene sequence of strain HJ50(T) (1430 nt) and those of type strains of members of the genus Roseovarius were 94.1-96.3 %. DNA-DNA relatedness values between strain HJ50(T) and the type strains of members of the genus Roseovarius were low (1.3-24.6 %). Physiological and biochemical differences support assignment of strain HJ50(T) to the genus Roseovarius as a representative of a novel species. The name Roseovarius halotolerans sp. nov. is proposed, with HJ50(T) (=KCTC 22224(T) =LMG 24468(T)) as the type strain.</P>

Pedobacter composti sp. nov., isolated from compost

Lee, H.-G.,Kim, S.-G.,Im, W.-T.,Oh, H.-M.,Lee, S.-T. Microbiology Society 2009 International journal of systematic and evolutiona Vol.59 No.2

<P>A Gram-negative, aerobic, rod-shaped, non-motile, non-spore-forming bacterial strain, designated TR6-06(T), was isolated from a compost sample in South Korea and characterized taxonomically by using a polyphasic approach. The organism grew optimally at 30 degrees C and pH 6.5-7.0. The isolate was positive for catalase and oxidase tests, but negative for gelatinase and urease and for indole and H(2)S production. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain TR6-06(T) was most closely affiliated with members of the genus Pedobacter of the family Sphingobacteriaceae. Strain TR6-06(T) exhibited 16S rRNA gene sequence similarity values of 89.9-93.5 % to the type strains of species of the genus Pedobacter. The G+C content of the genomic DNA of strain TR6-06(T) was 41.9 mol%. The predominant respiratory quinone was MK-7. The major fatty acids were iso-C(15 : 0), iso-C(17 : 0) 3-OH, C(16 : 1)omega7c and anteiso-C(15 : 0). These chemotaxonomic data support the affiliation of strain TR6-06(T) to the genus Pedobacter. However, on the basis of its phenotypic properties and phylogenetic distinctiveness, strain TR6-06(T) (=KCTC 12638(T)=LMG 23490(T)) should be classified as the type strain of a novel species, for which the name Pedobacter composti sp. nov. is proposed.</P>

Cytogenetic heterogeneity and their serial dynamic changes during acquisition of cytogenetic aberrations in cultured mesenchymal stem cells

Kim, J.A.,Im, K.O.,Park, S.N.,Kwon, J.S.,Kim, S.Y.,Oh, K.,Lee, D.S.,Kim, M.K.,Kim, S.W.,Jang, M.,Lee, G.,Oh, Y.M.,Lee, S.D.,Lee, D.S. Elsevier Science Publishers 2015 Mutation research Vol.777 No.-

To minimize the risk of tumorigenesis in mesenchymal stem cells (MSCs), G-banding analysis is widely used to detect chromosomal aberrations in MSCs. However, a critical limitation of G-banding is that it only reflects the status of metaphase cells, which can represent as few as 0.01% of tested cells. During routine cytogenetic testing in MSCs, we often detect chromosomal aberrations in minor cell populations. Therefore, we aimed to investigate whether such a minority of cells can expand over time or if they ultimately disappear during MSC passaging. We passaged MSCs serially while monitoring quantitative changes for each aberrant clone among heterogeneous MSCs. To investigate the cytogenetic status of interphase cells, which represent the main population, we also performed interphase FISH analysis, in combination with G-banding and telomere length determination. In human adipose tissue-derived MSCs, 4 types of chromosomal aberrations were found during culturing, and in umbilical cord MSCs, 2 types of chromosomal aberrations were observed. Sequential dynamic changes among heterogeneous aberrant clones during passaging were similar to the dynamic changes observed in cancer stem cells during disease progression. Throughout all passages, the quantitative G-banding results were inconsistent with those of the interphase FISH analysis. Interphase FISH revealed hidden aberrations in stem cell populations with normal karyotypes by G-banding analysis. We found that telomere length gradually decreased during passaging until the point at which cytogenetic aberrations appeared. The present study demonstrates that rare aberrant clones at earlier passages can become predominant clones during later passages. Considering the risk of tumorigenesis due to aberrant MSCs, we believe that our results will help to establish proper safety guidelines for MSC use. In particular, we believe it is critical to test for chromosomal aberrations using both G-banding and FISH to ensure the safety of human stem cells that are manufactured in vitro for clinical applications.

284 KINETICS OF OOCYTE MATURATION AND SUBSEQUENT DEVELOPMENT OF PARTHENOGENETIC PORCINE EMBRYOS AFTER MEIOTIC INHIBITION WITH ROSCOVITINE

Kim, D.H.,Kim, S.W.,Im, G.S.,Yang, B.C.,Lee, D.R.,Park, H.S.,Hwang, I.S.,S Seo, J.,Yang, B.S.,Chang, W.K. CSIRO Publishing 2005 Reproduction, fertility, and development Vol.17 No.1-2

<P> Maturation of mammalian oocytes is a very important process for subsequent embryo development after fertilization. Prolonged maturation time by meiotic inhibitors could be an effective method for improvement in the meiotic and developmental competence of mammalian oocytes. Roscovitine, a cyclin dependent kinase inhibitor, is known to specifically inhibit M-phase promoting factor (MPF) kinase activity and prevent the resumption of meiosis. The aim of this study was to examine the effect of roscovitine on the maturation and subsequent development of porcine oocytes. Ovaries were collected from slaughtered prepubertal gilts and COCs were aspirated from 2- to 5-mm antral follicles. In control, porcine cumulus oocyte complexes (COCs) were cultured in the maturation medium (TCM-199 supplemented with 0.3% BSA, 1 μg/mL FSH, 1 μg/mL LH, and 10 ng/mL EGF) for 44 h. In the experimental group, COCs were cultured in the inhibition medium (TCM-199 supplemented with 0.3% BSA and roscovitine) for 24 h, and then further cultured in the maturation medium for 44 h. Matured oocytes from both groups were activated by electrical pulse (1.2 kV/cm for 30 μs), and then cultured in PZM-3 medium for 6 days. Apoptotic cells in blastocysts were detected by TUNEL assay and total cell number was examined by propidium iodide (PI) counterstaining. Data were analyzed by chi-square and Student's t-test. The first experiment was conducted to determine the effect of roscovitine (0, 12.5, 25, 50, and 100 μM) on meiotic inhibition of GV oocytes. This effect was dose-dependent, and a concentration of 50 μM was sufficient to prevent meiotic resumption in 79.2% (76/96, 5 replicates) of the porcine oocytes after 24 h of culture when compared to 0 (15.4%, 15/97), 12.5 (32.1%, 36/112), 25 (57.4%, 54/94), and 100 μM (77.8%, 77/99). The second experiment was carried out to examine the kinetics of maturation of roscovitine-treated porcine oocytes. The concentration of roscovitine used was 50 μM. A total of 75.8% (50/66, 3 replicates) of roscovitine-treated oocytes reached metaphase II stage compared with 70.8% (46/65) of control. The third experiment was performed to compare embryo development between control and treated group after parthenogenetic activation. No differences (P > 0.05) were found between the control and the treated group in cleavage rate (77.2%, 132/171 vs. 68.0%, 115/169), blastocyst rate (26.9%, 46/171 vs. 17.8%, 30/169), and total (33.7 ± 12.4 vs. 35.1 ± 12.6) and apoptotic (2.2 ± 2.4 vs. 2.2 ± 1.2) cell number per blastocyst (4 replicates). The results suggest that roscovitine can be used to prolong maturation time of porcine oocytes without reducing meiotic maturation but also without significantly decreasing their subsequent developmental competence. Further studies are necessary to improve the developmental competence of porcine oocytes treated with roscovitine.</P>

Failure of a breakwater founded on a thick normally consolidated clay layer

Chung, S. G.,Kim, S. K.,Kang, Y. J.,Im, J. C.,Prasad, K. N. INSTITUTION OF CIVIL ENGINEERS 2006 Géotechnique Vol.56 No.6

Effects of heat and momentum losses on the stability of premixed flames in a narrow channel

Kang, S. H.,Baek, S. W.,Im, H. G. Taylor Francis 2006 COMBUSTION THEORY AND MODELLING Vol.10 No.4

<P> To understand fundamental characteristics of combustion in a small-scale device, the effects of the momentum and heat loss on the stability of laminar premixed flames in a narrow channel are investigated by two-dimensional high-fidelity numerical simulations. A general finding is that momentum loss promotes the Saffman-Taylor (S-T) instability, which is additive to the Darrieus-Landau (D-L) instabilities, while the heat loss effects result in an enhancement of the diffusive-thermal (D-T) instability. It is also found that heat loss amplifies the sensitivity of the growth rate to the Lewis number variation, and the critical Lewis number of neutral stability also increases with heat loss. The two competing effects between the heat and momentum losses play an intricate role in determining the overall instability and cell formation patterns. The simulations of multiple cell interactions revealed that D-T instability mechanism is primarily responsible for the splitting into smaller flame cells, while the D-L and S-T mechanisms favour larger flame cells through merging. The relative sensitivity of the flame instability to the momentum or heat loss effect is also examined by a numerical experiment for different Lewis number cases.</P>

Highly reliable hybrid nano-stratified moisture barrier for encapsulating flexible OLEDs

Jeong, E.G.,Han, Y.C.,Im, H.G.,Bae, B.S.,Choi, K.C. Elsevier Science 2016 ORGANIC ELECTRONICS Vol.33 No.-

<P>Herein, a novel thin-film encapsulation for flexible organic light-emitting diodes (FOLEDs) is proposed, and its long-term reliability in tensile stress conditions was tested. The hybrid nano-stratified moisture barrier consists of 2.5 dyads of an Al2O3/ZnO nano-stratified structure and a S-H nanocomposite organic layer. The nano-stratified structure is prepared by low-temperature atomic layer deposition and the S-H nanocomposite by spin-coating at a thickness of 30 and 120 nm, respectively. An optical transmittance of 89.05% was measured with the 2.5-dyad hybrid nano-stratified moisture barrier with a total thickness of 330 nm. A low water vapor transmission rate (WVTR) of 1.91 x 10(-5) g/m(2) day was recorded based on an electrical Ca test at 30 degrees C and 90% R.H. without losing its properties after a bending test. With this highly reliable hybrid nano-stratified moisture barrier, FOLEDs were successfully encapsulated. After 30 days under conditions of 30 degrees C and 90% R.H. with tensile stress, the J-V-L performances of the FOLEDs were comparable to those of the initial state without dark spots. These results suggest that this hybrid nanostratified moisture barrier is an excellent method for encapsulating FOLEDs. (C) 2016 Elsevier B.V. All rights reserved.</P>