• Title/Summary/Keyword: Stability Agent

Search Result 625, Processing Time 0.031 seconds

Effects of Disulfide and Thioether Linkages on Stability and Cytotoxicity of Anti-CALLA Fab-Ricin A Immunotoxins

  • Lee, Jung-Tae;Woo, Byung-Ho;Lee, Kang-Choon
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 1996.04a
    • /
    • pp.277-277
    • /
    • 1996
  • Anti-CALLA Fab-RTA immunotoxins were constructed using two crosslinking agent, SMPT and SMCC, to generate a disulfide and a thioether bridge between Fab fragment of K269-65 MoAb and RTA toxin moieties, respectively. These immunotoxins were selectively immunoreative with CALLA$\^$+/ B-lineage Daudi cells. SMPT and SMCC mediated RTA immunotoxins were prepared with 49% and 53% of the RTA conjugation yields, respectively. SDS-PAGE analysis show that immunotoxins were constructed with major Fab-1 RTA (76kda), minor Fab-2RTA (106kda) and Fab-3RTA (136kda) compositions. The breakdown rates of immunotoxins were determined in the presence of glutathione by measuring the amount of reduced immunotoxins using size-exclusion HPLC. The SMCC immunotoxins were more resistant to the glutathione than SMPT immunotoxins. But, our data showed that the SMPT mediated disulfide bonded immunotoxins were much more active than the SMCC mediated thioether bonded immunotoxins to kill the target cells in vitro.

  • PDF

Molecular epidemiology of norovirus in South Korea

  • Lee, Sung-Geun;Cho, Han-Gil;Paik, Soon-Young
    • BMB Reports
    • /
    • v.48 no.2
    • /
    • pp.61-67
    • /
    • 2015
  • Norovirus is a major cause of viral gastroenteritis and a common cause of foodborne and waterborne outbreaks. Norovirus outbreaks are responsible for economic losses, most notably to the public health and food industry field. Norovirus has characteristics such as low infectious dose, prolonged shedding period, strong stability, great diversity, and frequent genome mutations. Besides these characteristics, they are known for rapid and extensive spread in closed settings such as hospitals, hotels, and schools. Norovirus is well known as a major agent of food-poisoning in diverse settings in South Korea. For these reasons, nationwide surveillance for norovirus is active in both clinical and environmental settings in South Korea. Recent studies have reported the emergence of variants and novel recombinants of norovirus. In this review, we summarized studies on the molecular epidemiology and nationwide surveillance of norovirus in South Korea. This review will provide information for vaccine development and prediction of new emerging variants of norovirus in South Korea.

Effect of DP Finishing Conditions on the Mechanical Properties and Hand of Cotton Fabrics (DP 가공조건이 면직물의 역학적 성질과 태에 미치는 영향)

  • 신윤숙
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.24 no.3
    • /
    • pp.440-447
    • /
    • 2000
  • The effects of DP finishing conditions including process technique and finishing agent on the mechanical properties and hand of cotton fabrics were investigated. 100% cotton fabrics were treated with NMA/DMDHEU and NMA/YF using wet-fixation and steam-fixation process. For comparison, conventional pad-dry-cure process was used with DMDHEU. After DP finishing, tensile and compressional resilience increased and bending hysteresis decreased, resulting in the improvement of dimensional stability of cotton fabric. WF and SF process rendered fabrics better shear properties, tensile energy, and compressional linearity and energy than PDC process. However, SF process produced fabrics with higher geometrical roughness than WF process. After DP finishing, primary hand values except Koshi increased, resulting in the increase of total hand value of cotton fabric.

  • PDF

Setting Properties of Disulfide-Crosslinked Silk Fiber (Disulfide 가교 견섬유의 Set 성)

  • ;;M. Sakamoto
    • Textile Coloration and Finishing
    • /
    • v.1 no.1
    • /
    • pp.1-6
    • /
    • 1989
  • The reaction of silk with a disulfide-containing crosslinking agent, i.e. bis($\beta$-isocyanatoethyl)disulfide(BIED), was studied in an attempt to obtain disulfide-crosslinked silk. The setting properties of disulfide-crosslinked silk fibers were studied. The permanent set values of single fibers were evaluated after the set fibers were relaxed in boiling water. When single fibers were set in boiling water or in boiling alkaline solution, the permanent set values of BIED-treated silk fibers were less than those of untreated silk fibers. When the fibers were treated with 2% thioglycolic acid solution at $60^\circ{C}$ followed by oxidation, settability of BIED-treated silk was better than that of untreated silk. The rearrangement of secondary bonds faciliated by cleavage of crosslinks as well as the rearrangement of crosslinks itself seems to be an important role in the set stability.

  • PDF

A Study on Iron Electrode of Ni/Fe Battery(II) (니켈/철 축전지의 철전극에 관한 연구(II))

  • 김운석;박성용;조원일;조병원;윤경석
    • Journal of Energy Engineering
    • /
    • v.2 no.3
    • /
    • pp.300-307
    • /
    • 1993
  • To develop high performance nickel-iron secondary battery, the characteristics of charge-discharge reaction of iron electrode were examined by cyclic voltammetry technique, SEM and XRD analysis. The capacity of the test electrodes was determined by the constant current charge-discharge method. It was found that the temperature and concentration of electrolyte were the major determinant factors of electrode capacity, and especially the 1st discharge capacity was increased with the increase of temperature. The effect of fore forming agent on the electrode capacity was negligible. The electrode capacity was above 350 ㎃h/g(36% utility) at 0.25C discharge rate. The stability of electrode was very good, but the activation occurred slowly.

  • PDF

1-Hydroxy-4-tosyloxy cyclohexane and 1,4-Ditosyloxy cyclohexane as Acid Amplifiers To Enhance the Photosensitivity of Positive-Working Photoresists (포지티브 포토레지스트의 감도 증진을 위한 산증식제로 1-Hydroxy-4-tosyloxy cyclohexane과 1,4-Ditosyloxy cyclohexane에 관한 연구)

  • 정연태;이은주;권경아
    • Journal of the Korean Graphic Arts Communication Society
    • /
    • v.20 no.1
    • /
    • pp.91-101
    • /
    • 2002
  • An acid amplifier is defined as an acid-generating agent which is decomposed autocatalytically to produce new strongly acidic molecules in a non-liner manner, The addition of the acid amplifiers to conventional chemically amplified photoresists consisting of photoacid generators and acid-sensitive polymers result in the improvement of photosensitivity due to the amplified generation of catalytic acid molecules as a result of the decomposition of acid amplifiers. We synthesized and evaluated 1-hydroxy-4-tosyloxy cyclohexane(AA-1) and 1,4-ditosyloxy cyclohexane(Ah-2) as novel acid amplifiers. The acid amplifiers(AA-1, AA-2) showed reasonable thermal stability for resist processing temperature. As estimated by the sensitivity curve, tort-butyl methacrylate homopolymer(ptBMA) film doped with AA-1 or 2 exhibited much higher photosensitivity than ptBMA film without AA-1 or 2. And AA-1 showed higher effect than AA-2 on enhancing photosensitivity of ptBMA film.

  • PDF

In-vitro and In-vivo Evaluation of the DTBP Crosslinked Collagen and Gelatin Coated Porous Spherical BCP Granules for Using as Granular Bone Substitutes

  • Kim, Yang-Hee;Lee, Byong-Taek
    • Proceedings of the Materials Research Society of Korea Conference
    • /
    • 2011.05a
    • /
    • pp.54.2-54.2
    • /
    • 2011
  • DTBP (dimethyl 3,3`-dithiobispropionimidate) was applied to collagen and gelatin coating on BCP granules and a crosslinking agent. The DTBP crosslinking was done for decreasing the solubility of the coating and hence increasing the stability. The nanostructure of collagen and gelatin coating surfaces were observed by SEM technique. Based on the DSC thermograms and FT-IR spectrums, the crosslinkings were confirmed between collagen molecules and gelatin molecules. The compressive strength was measured before crosslinking and after that. In-vitro study was carried out by measuring cell viability and observing cell morphology after DTBP crosslinking. Moreover, the proliferation ability of MG-63 osteoblast-like cells on the crosslinked BCP granules was evaluated by Western blot assay. The BCP granules were implanted into rabbit femur for 4 weeks and 12 weeks. The bone tissue formation was analyzed with micro-computed tomography (micro-CT) and histological analysis was also carried out by hematoxylin and eosin (H&E) staining for visualization of cells.

  • PDF

Luminescent Polynorbornene/Quantum Dot Composite Nanorods and Nanotubes Prepared from AAO Membrane Templates

  • Oh, Se-Won;Cho, Young-Hyun;Char, Kook-Heon
    • Macromolecular Research
    • /
    • v.17 no.12
    • /
    • pp.995-1002
    • /
    • 2009
  • Luminescent polynorbornene (PNB)/quantum dot (CdSe@ZnS; QD) composite nanorods and nanotubes were successfully prepared using anodic aluminum oxide (AAO) membranes of various pore sizes as templates. To protect QDs with high quantum yield from quenching during the phosphoric acid treatment used to remove the AAO templates, chemically stable and optically clear norbornene-maleic anhydride copolymers (P(NB-r-MA)) were employed as a capping agent for QDs. The amine-terminated QDs reacted with maleic anhydride moieties in P(NB-r-MA) to form PNB-grafted QDs. The chemical- and photo-stability of QDs encapsulated with PNB copolymers were investigated by photoluminescence (PL) spectroscopy. By varying the pore size of the AAO templates from 40 to 380 urn, PNB/QD composite nanorods or nanotubes were obtained with a good dispersion of QDs in the PNB matrix.

Studies of 8-Hydroxyquinoline Derivatives (Part II) Fe (II)-7-Nitroso-8-Hydroxyquinoline-5-Sulfonate (8-Hydroxyquinoline 誘導體에 關한 硏究 (第2報) Fe (II)-7-Nitroso-8-Hydroxyquinoline-5-Sulfonate 에 關하여)

  • Lee, Dong-Hyung
    • Journal of the Korean Chemical Society
    • /
    • v.9 no.1
    • /
    • pp.41-44
    • /
    • 1965
  • The properties of Fe(II)-7-nitrose-8-hydroxyquinoline-5-sulfonate have been studied spectrophotometrically at 700$m{\mu}$, $26^{\circ}C$. The absorbance of the complex shows a maximum at pH 6.0 and good thermal stability. Excess of the ligand and the reducing agent do not interfere the formation of the complex. The composition of the complex is found to be 3:1 ligand to metal species by molar ratio and continues variation methods. Calibration curve follow Beer's law over the range of concentratiion studied.

  • PDF

Antiviral Activity Enhancement through the SATE Prodrug of a 2'-Modified 5'-Norcarbocyclic Adenine Analogue

  • Li, Hua;Kim, Si-Wouk;Hong, Joon-Hee
    • Bulletin of the Korean Chemical Society
    • /
    • v.31 no.8
    • /
    • pp.2180-2184
    • /
    • 2010
  • We synthesized and tested the anti-HIV activity of the SATE prodrug of a 2'-methyl 5'-norcarbocyclic adenine analogue. The introduction of a methyl group in the 2'-position was performed by the addition of a carbonyl using isopropenyl magnesium bromide. The adenine base was efficiently coupled using the Mitsunobu reaction. The chemical stability study of the bis(SATE) derivative 18 was measured at neutral (pH 7.2) and slightly acid (milli-Q water, pH 5.5) pH, and compounds 16 and 18 were evaluated as potential anti-HIV-1 agents.