• Title/Summary/Keyword: C1-2 fusion

Search Result 544, Processing Time 0.025 seconds

Protoplast Fusion Between Aspergillus oryzae and Aspergillus shirousamii (Aspergillus oryzae와 Aspergillus shirousamii간의 원형질체의 융합)

  • Shin, Dong-Bun;Ryu, Beung-Ho;Jin, Seung-Heun
    • Korean Journal of Food Science and Technology
    • /
    • v.25 no.4
    • /
    • pp.366-372
    • /
    • 1993
  • This study mainly designed to high quality of mirin production by using protopast fusion. In order to enhance the acid carboxypeptidase (ACPase) activity by the method of protoplast fusion. In order to enhance the acid carboxypeptidase (ACPase) activity by the method of protopalst fusion, the mutants, Aspergillus oryzae 9-12 and Aspergillus shirosamii IFO 6082-60 were selected by mutation among various mutants. Protoplast of Aspergillus oryzae 9-12 and Aspergillus shirousamii IFO 6082-60 were formed effectively by incubation of the mixtures of chitinase (10mg/ml), cellulase (10mg/ml) and zymolase 20T (5mg/ml). For protopalst fusion, the mixture of two mutant were fused to effective under the optimum conditions by solutions containing 30% PEG 6,000, 0.01M $CaCl_2\;2H_2O$, 0.6M KCl and 0.05M glycine. Fusion frequency was 0.71% and fusant, F-50 appeared ACPase activity of 20,800 unit/g which has 1.5 times higher than that of each mutants.

  • PDF

Temperature-dependent Structural and Magnetic Properties of Diamagnetic $HgI_2$

  • Park, C.I.;Jin, Zhenlan;Hwang, I.H.;Yeo, S.M.;Han, S.W.
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2013.08a
    • /
    • pp.291.1-291.1
    • /
    • 2013
  • We examined the temperature-dependent structural and magnetic properties of HgI2 in the temperature range of 300~400 K. HgI2 is a diamagnetic material and can be used for X-ray or γ-ray detectors. DCmagnetization measurements on HgI2 showed that there is a small but distinguishable change in its diamagnetic properties near 375 K. The magnetic property change is not expected because Hg and I are known as nonmagnetic elements. X-ray diffraction (XRD) measurements revealed a structural transition in the temperature of 350~400 K. Temperature-dependent x-ray absorption fine structure (XAFS) demonstrated that the chemical valence states of both Hg and I did not changed in the temperature range of 300~400 K. However, XAFS revealed that the bond-length disorder was slightly increased in the temperature range, particularly, near Hg atoms. The structural changes of HgI2 are likely related to its diamagnetic property change. We will discuss the relation between the diamagnetic properties and local structural properties of HgI2 in detail.

  • PDF

Acacetin-induced Apoptosis of Human Breast Cancer MCF-7 Cells Involves Caspase Cascade, Mitochondria-mediated Death Signaling and SAPK/JNK1/2-c-Jun Activation

  • Shim, Hye-Young;Park, Jong-Hwa;Paik, Hyun-Dong;Nah, Seung-Yeol;Kim, Darrick S.H.L.;Han, Ye Sun
    • Molecules and Cells
    • /
    • v.24 no.1
    • /
    • pp.95-104
    • /
    • 2007
  • The mechanism of acacetin-induced apoptosis of human breast cancer MCF-7 cells was investigated. Acacetin caused 50% growth inhibition ($IC_{50}$) of MCF-7 cells at $26.4{\pm}0.7{\mu}M$ over 24 h in the MTT assay. Apoptosis was characterized by DNA fragmentation and an increase of sub-G1 cells and involved activation of caspase-7 and PARP (poly-ADP-ribose polymerase). Maximum caspase 7 activity was observed with $100{\mu}M$ acacetin for 24 h. Caspase 8 and 9 activation cascades mediated the activation of caspase 7. Acacetin caused a reduction of Bcl-2 expression leading to an increase of the Bax:Bcl-2 ratio. It also caused a loss of mitochondrial membrane potential that induced release of cytochrome c and apoptosis inducing factor (AIF) into the cytoplasm, enhancing ROS generation and subsequently resulting in apoptosis. Pretreatment of cells with N-acetylcysteine (NAC) reduced ROS generation and cell growth inhibition, and pretreatment with NAC or a caspase 8 inhibitor (Z-IETD-FMK) inhibited the acacetin-induced loss of mitochondrial membrane potential and release of cytochrome c and AIF. Stress-activated protein kinase/c-Jun $NH_4$-terminal kinase 1/2 (SAPK/JNK1/2) and c-Jun were activated by acacetin but extracellular-regulated kinase 1/2 (Erk1/2) nor p38 mitogen-activated protein kinase (MAPK) were not. Our results show that acacetin-induced apoptosis of MCF-7 cells is mediated by caspase activation cascades, ROS generation, mitochondria-mediated cell death signaling and the SAPK/JNK1/2-c-Jun signaling pathway, activated by acacetin-induced ROS generation.

A Novel Multi-focus Image Fusion Scheme using Nested Genetic Algorithms with "Gifted Genes" (재능 유전인자를 갖는 네스티드 유전자 알고리듬을 이용한 새로운 다중 초점 이미지 융합 기법)

  • Park, Dae-Chul;Atole, Ronnel R.
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.9 no.1
    • /
    • pp.75-87
    • /
    • 2009
  • We propose in this paper a novel approach to image fusion in which the fusion rule is guided by optimizing an image clarity function. A Genetic Algorithm is used to stochastically select, comparative to the clarity function, the optimum block from among the source images. A novel nested Genetic Algorithm with gifted individuals found through bombardment of genes by the mutation operator is designed and implemented. Convergence of the algorithm is analytically and empirically examined and statistically compared (MANOVA) with the canonical GA using 3 test functions commonly used in the GA literature. The resulting GA is invariant to parameters and population size, and a minimal size of 20 individuals is found to be sufficient in the tests. In the fusion application, each individual in the population is a finite sequence of discrete values that represent input blocks. Performance of the proposed technique applied to image fusion experiments, is characterized in terms of Mutual Information (MI) as the output quality measure. The method is tested with C=2 input images. The results of the proposed scheme indicate a practical and attractive alternative to current multi-focus image fusion techniques.

  • PDF

Construction of Heat-Inducible Expression Vector of Corynebacterium glutamicum and C. ammoniagenes: Fusion of ${\lambda}$ Operator with Promoters Isolated from C. ammoniagenes

  • Park, Jong-Uk;Jo, Jae-Hyung;Kim, Young-Ji;Chung, So-Sun;Lee, Jin-Ho;Lee, Hyune-Hwan
    • Journal of Microbiology and Biotechnology
    • /
    • v.18 no.4
    • /
    • pp.639-647
    • /
    • 2008
  • The heat-inducible expression vectors for Corynebacterium glutamicum and C. ammoniagenes were constructed by using the ${\lambda}O_L1$ and the cryptic promoters, CJ1 and CJ4 that express genes constitutively in C. ammoniagenes. Although the promoters were isolated from C. ammoniagenes, CJ1 and CJ4 were also active in C. glutamicum. To construct vectors, the $O_L1$ from the ${\lambda}P_L$ promoter was isolated and fused to the CJ1 and CJ4 promoters by recombinant PCR. The resulting artificial promoters, CJ1O and CJ4O, which have one ${\lambda}O_L1$, and CJ1OX2, which has two successive ${\lambda}O_L1$, were fused to the green fluorescent protein (GFP) gene followed by subcloning into pCES208. The expression of GFP in the corynebacteria harboring the vectors was regulated successfully by the temperature-sensitive cI857 repressor. Among them, C. ammoniagenes harboring plasmid pCJ1OX2G containing GFP fused to CJ1OX2 showed more GFP than the other ones and the expression was tightly regulated by the repressor. To construct the generally applicable expression vector using the plasmid pCJ1OX2G, the His-tag, enterokinase (EK) moiety, and the MCS were inserted in front of the GFP gene. Using the vector, the expression of pyrR from C. glutamicum was tried by temperature shift-up. The results indicated that the constructed vectors (pCeHEMG) can be successfully used in the expression and regulation of foreign genes in corynebacteria.

Effect of Cell Cycle Stage on the Development of Embryos Produced by Cumulus Cell Nuclear Transfer in Hanwoo (Korean Cattle)

  • Im, G.S.;Yang, B.S.;Yang, B.C.;Chang, W.K.;Yi, Y.J.;Park, C.S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.14 no.6
    • /
    • pp.759-764
    • /
    • 2001
  • This study was carried out to investigate the effect of activation timing, cell cycle and passage on the development of embryos produced by cumulus cell nuclear transfer in Hanwoo (Korean cattle). Nuclear donor cumulus cells were cultured in Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum at $38.5^{\circ}C$ in a humidified atmosphere of 5% $CO_2$ in air. The 1~6 passages of serum deprived or actively dividing cumulus cells were isolated and used as donor cells. The in vitro matured oocytes were enucleated and then the isolated donor cells were introduced. One pulse of 180 volts for $15{\mu}s$ was applied to induce the fusion between karyoplast and cytoplast. The activation was done before or after the fusion. To activate, oocytes were treated with $10{\mu}M$ calcium ionophore for 5 min immediately followed by 2 mM 6-dimethylaminopurine for 3 h. The nuclear transfer embryos were cultured in $500{\mu}l$ of modified CRlaa supplemented with 3 mg/ml BSA in four well dish covered with mineral oil. After 3 days culture, culture medium was changed into modified CRlaa medium containing 1.5 mg/ml BSA and 5% FBS for 4 days. The incubation environment was 5% $CO_2$, 5% $O_2$, 90% $N_2$ at $38.5^{\circ}C$. There was no blastocyst formation when the nuclear transfer embryos were activated before the fusion, whereas, 29.9% of blastocyst formation was shown when the nuclear transfer embryos were activated after the fusion. When serum deprived and actively dividing cumulus cells were used as nuclear donor cells, the developmental rates to blastocyst were 38.5% and 40.6%, respectively. There was no significant difference between serum deprived and actively dividing cells in the developmental rates. The developmental rates to blastocyst according to 1~6 passages were 37.5~44.4%. However, there were no significant differences among passages. These results indicate that 1~6 passage cumulus cell irrespective of cell cycle could support development of nuclear transfer embryos activated after the fusion.

A study on the fracture toughness degradation in cryogenic structural material using single-specimen method (단일 시험편법에 의한 극저온용 구조재료의 파괴인성 저하에 관한 연구)

  • Kwon, Il-hyun
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.22 no.2
    • /
    • pp.343-351
    • /
    • 1998
  • This paper was investigated degradation of the fracture toughness caused by sensitizing heat-treatment of the cryogenic structural material JN1 base metal using unloading compliance method reported as useful a method in evaluating the elastic-plastic fracture toughness at cryogenic temperature. The specimens used in this paper were 20% side-grooved 0.5T-CT specimens which were machined in the JN1 base metal. Also, to investigate cryogenic fracture toughness of the fusion line region in the JN1 GTA weldments, it was also used 20% side-grooved 0.5T-CT specimens that was machined fusion line to located in the middle of the specimen. The cryogenic fracture toughness values of the JN1 base metal were significantly decreased with increasing the time and temperature of the heat treatment. The fracture toughness value obtained from the fusion line specimen was invalid, but it was lower value than that of the JN1 base metal. Especially, this value was approximately equal with that obtained from the JN1 650.deg. C-5h heat-treated material.

Expression of Polyhistidine-Containing Fusion Human HepG2 Type Glucose Transport Protein in Spodoptera Cells and Its Purification Using a Metal Affinity Chromatography

  • Lee, Chong-Kee
    • Biomedical Science Letters
    • /
    • v.16 no.3
    • /
    • pp.201-206
    • /
    • 2010
  • In order to develop procedures for the rapid isolation of recombinant sugar transporter in functional form from away from the endogenous insect cell transporter, gene fusion techniques were exploited. Briefly, BamH1-digested human HepG2 type glucose transport protein cDNA was first cloned into a transfer vector pBlueBacHis, containing a tract of six histidine residues. Recombinant baculoviruses including the human cDNA were then generated by allelic exchange following transfection of insect cells with wild-type BaculoGold virus DNA and the recombinant transfer vector. Plaque assay was then performed to obtain and purify recombinant viruses expressing the human transport protein. All the cell samples that had been infected with viruses from the several blue plaques exhibited a positive reaction in the immnuassay, demonstrating expression of the glucose transport protein. In contrast, no color development in the immunoassay was observed for cells infected with the wild-type virus or no virus. Immunoblot analysis showed that a major immunoreactive band of apparent Mr 43,000~44,000 was evident in the lysate from cells infected with the recombinant baculovirus. Following expression of the recombinant fusion protein with the metal-binding domain and enterokinase cleavage site, the fusion protein was recovered by competition with imidizole using immobilized metal charged resin. The leader peptide was then removed from the fusion protein by cleavage with porcine enterokinase. Final separation of the recombinant protein of the interest was achieved by passage over $Ni^{2+}$-charged resin under binding conditions. The expressed transport protein bound cytochalasin B and demonstrated a functional similarity to its human counterpart.

Phosphorylation of Transcriptional Factor by Mitogen-activated Protein (MAP) Kinase Purified from Nucleus (핵 내에서 분리한 Mitogen-Activated Protein (MAP) Kinase의 Transcription Factor에 대한 인산화)

  • 김윤석;김소영;김태우
    • Biomedical Science Letters
    • /
    • v.2 no.2
    • /
    • pp.175-185
    • /
    • 1996
  • The mitogen-activated protein(MAP) kinase signal transduction pathway represents an important mechanism by which mitogen, such as serum and PMA, regulate cell proliferation and differentiation. Target substrates of the MAP kinase are located within several compartments containing plasma membranes and nucleus. We now report that serum addition induces proliferation of the P388 murine leukemia cell, but PMA does not, while both serum and PMA treatment cause translocation of the MAP kinase, mainly p42$^{mapk}$ isoform, from cytosol into the nucleus, which was monitored by immunoblot analysis using polyclonal anti-ERK1 antibodies. We investigated whether the MAP kinase was capable of phosphorylating c-Jun protein and GST-fusion proteins, the P562$^{kk}$N-terminal peptides (1-77 or 1-123 domain) of the T cell tyrosine kinase, using the partially purified MAP kinase by SP-sephadex C-50, phenyl superose and Mono Q column chromatography. We found that the partially purified MAP kinase was able to phosphorylate c-Jun protein and the GST-fusion protein expressed using E.coli DH5$\alpha$ which is transformed with pGEX-3Xb plasmid vector carrying of p562$^{kk}$N-terminal peptide-encoding DNA. These results imply that tyrosine kinase receptor/Ras/Raf/MAP kinase pathway is a major mechanism for mitogen-induced cell proliferation in P388 murine leukemia cell and that the various MAP kinase isoforms may have their own target substrates located in distinct subcellular compartments.

  • PDF

The endoscopic transnasal approach to the lesions of the craniocervical junction: two case reports

  • Baraa Dabboucy;Wissem Lahiani;Damien Bresson;Nouman Aldahak
    • Journal of Yeungnam Medical Science
    • /
    • v.40 no.1
    • /
    • pp.96-101
    • /
    • 2023
  • The endoscopic endonasal approach (EEA) to the craniovertebral junction (CVJ) has recently been considered a safer alternative and less invasive approach than the traditional transoral approach because the complications associated with the latter are avoided or minimized. Here, we present two challenging cases of CVJ pathologies. The first case involved os odontoideum associated with anterior displacement of the occipitocervical junction where the EEA was used, followed by C0-C1-C2 fusion using a posterior approach to decompress the CVJ, and was complicated by rhinorrhea and Candida albicans meningitis. The second case involved basilar invagination with syringomyelia previously treated using a posterior approach, where aggravation of neuropathic symptoms required combined treatment with EEA and occipitocervical fusion of C0-C2-C3-C4, with the postoperative course challenged by operative site infection requiring drainage with debridement and antibiotic therapy. The EEA is an alternative approach for accessing the CVJ in well-selected patients. Knowledge of EEA complications is crucial for the optimal care of patients.