• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.894-905
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• 1992

Dioxygen binding and homogeneous catalytic oxidation of hydrazobenzene were investigated by employing tetradentate Schiff base Cobalt(II) complexes such as Co(II)(SED)$(Py)_2$, Co(II)(SOPD)$(Py)_2$ and Co(II)(SND)$(Py)_2$ in saturated oxygen methanol solvent. The major product of hydrazobenzene ($H_2$AB) oxidation by catalysts of superoxo type [Co(III)(SED)(Py)$O_2$] and [Co(III)(SOPD)(Py)$O_2$] complexes are trans-azobenzene (t-AB) and rate constants k for oxidation reaction was 7.692 ${\times}$ $10^{-2}$ M/sec for [Co(III)(SED)(Py)$O_2$] and 5.076 ${\times}$ $10^{-2}$ M/sec for [Co(III)(SOPD)(Py)$O_2$]. But cis-azobenzene (c-AB) are obtained as a major product with ${\mu}$-peroxo type [Co(III)(SED)(Py)]$_2O_2$ catalyst, and rate constant k is 1.266 ${\times}$ $10^{-2}$ M/sec. The rate constants of oxidation reaction has been studied spectrophotometrically and the rate law established. A mechanism involving a intermediate activated complexes of catalyst, hydrazobenzene and oxygen has been proposed. $H_2$AB + Co(II)(Schiff base)$(Py)_2$ + $O_2$ ${\rightleftharpoons}_{MeOH}^K$ Co(III)(Schiff base)(Py)$O_2$${\cdot}$$H_2$AB + Py $\longrightarrow^k$ Co(II)(Schiff base)$(Py)_2$ + t-AB + $H_2O_2$(Scchiff base : SED and SOPD). $H_2$AB + 2Co(II)(SND)$(Py)_2$ + $O_2$ ${\rightleftharpoons}_{MeOH}^K$ [Co(III)(SND)(Py)]$_2O_2$${\cdot}$H_2$AB + 2Py ${\longrightarrow}^k$ (Co(II)(SND)$(Py)_2$ + c-AB + $H_2O_2$.

• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1073-1079
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• 1998

The potential energy surface (PES) of the non-identical SN2 reactions, F- + CH3Cl → FCH3 + Cl and (H2O)F + CH3Cl → FCH3 + Cl-(H2O), were investigated with ab initio MO calculations. The ab initio minimum energy reaction path (MERP) of the F- + CH3Cl → FCH3 + Cl- was obtained and it was expressed with an intermediate variable t. The ab initio PES was obtained near around t. Analytical potential energy function (PEF) was determined as a function of the t in order to reproduce the ab initio PES. Based on Morse-type potential energy function, a Varying Repulsive Cores Model (VRCM) was proposed for the description of the bond forming and the bond breaking which occur simultaneously during the SN2 reaction. The MERP calculated with the PEF is well agreed with the ab initio MERP and PEF could reproduce the ab initio PES well. The potential parameters for the interactions between the gas phase molecules in the reactions and water were also obtained. ST2 type model was used for the water.

• Restorative Dentistry and Endodontics
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• v.36 no.4
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• pp.280-289
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• 2011

Objectives: The purpose of this study was to evaluate ${\mu}TBS$ (microtensile bond strength) of current dentin bonding adhesives which have different hydrophobicity with low-shrinkage silorane resin. Materials and Methods: Thirty-six human third molars were used. Middle dentin was exposed. The teeth were randomly assigned to nine experimental groups: Silorane self-etch adhesives (SS), SS + phosphoric acid etching (SS + pa), Adper easy bond (AE), AE + Silorane system bonding (AE + SSb), Clearfil SE bond (CSE), CSE + SSb, All-Bond 2 (AB2), AB2 + SSb, All-Bond 3 (AB3). After adhesive's were applied, the clinical crowns were restored with Filtek LS (3M ESPE). The 0.8 mm ${\times}$ 0.8 mm sticks were submitted to a tensile load using a Micro Tensile Tester (Bisco Inc.). Water sorption was measured to estimate hydrophobicity adhesives. Results: ${\mu}TBS$ of silorane resin to 5 adhesives: SS, 23.2 MPa; CSE, 19.4 MPa; AB3, 30.3 MPa; AB2 and AE, no bond. Additional layering of SSb: CSE + SSb, 26.2 MPa; AB2 + SSb, 33.9 MPa; AE + SSb, no bond. High value of ${\mu}TBS$ was related to cohesive failure. SS showed the lowest water sorption. AE showed the highest solubility. Conclusions: The hydrophobicity of adhesive increased, and silorane resin bond-strength was also increased. Additional hydrophobic adhesive layer did not increase the bond-strength to silorane resin except AB2 + SSb. All-Bond 3 showed similar ${\mu}TBS$ & water sorption with SS. By these facts, we could reach a conclusion that All-Bond 3 is a competitive adhesive which can replace the Silorane adhesive system.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2795-2798
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• 2012

Objective: This study is conducted to evaluate the effects of anti-HER-2${\times}$anti-CD3 bi-specific antibodies(BsAb) on HER-2/neuover-expressing human colorectal carcinoma cells. Methods: Growth was assessed by MTT assays after exposure of HCT-116 cells to Herceptin, anti-CD3 and BsAb antibodies. Immunocytochemistry was applied to test the HER-2 level of HCT-116. In a nude mouse model, HER-2${\times}$CD3 BsAb was combined with effector cells (peripheral blood lymph cells from normal human being) for observations on in Vivo growth of tumors. Results: Compared with the control group, using effector cells combined with anti-CD3 McAb, Herceptin or HER2${\times}$CD3 BsAb, tumor cell growth in vitro and in vivo was significantly inhibited (P<0.05), most remarkably in the HER2${\times}$CD3 BsAb case. The growth of xenografts with HER2${\times}$CD3 BsAb combined with effector cells was also significantly inhibited when compared with the anti-CD3 McAb or Herceptin groups (P<0.05). Conclusion: HER-2/neu might be a useful target for immunotherapy in colorectal carcinoma, anti-HER2${\times}$anti-CD3 BsAb exerting clear anti-tumor effects.

• Biomolecules & Therapeutics
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• v.31 no.6
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• pp.611-618
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• 2023

Rhizome of Alisma orientale has been used as a traditional medicine for treating kidney diseases in East Asian countries. Its inhibitory effects on hypersensitivity responses have been reported for methanol extracts, with alisol B 23-acetate (AB23Ac) being the most active constituent among six terpenes in inhibiting the direct passive Arthus reaction. However, whether AB23Ac has efficacy against allergic asthma has not been tested to date. The in vivo efficacy of AB23Ac in an ovalbumin (OVA)-induced allergic asthma mouse model was evaluated by administrating AB23Ac before OVA sensitization or OVA challenge in BALB/c mice. AB23Ac suppressed antigen-induced degranulation of RBL-2H3 mast cells in a concentration-dependent manner. The administration of AB23Ac both before OVA sensitization and OVA challenge greatly lowered pulmonary resistance and the increase in immune cell counts and inflammatory responses around the peribronchial and perivascular regions. In addition, the inflammatory cytokine levels of Th1/Th2/Th17 cells in the bronchoalveolar lavage fluid decreased in the AB23Ac-treated groups. AB23Ac reduced the number of PAS-stained cells in the lungs. Furthermore, a computer modeling study indicated that AB23Ac can bind tightly to spleen tyrosine kinase (Syk). These results suggest that AB23Ac may ameliorate allergic asthma by suppressing immune responses in dendritic cells during sensitization and in mast cells during challenge periods.

• Journal of Preventive Medicine and Public Health
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• v.30 no.1 s.56
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• pp.1-15
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• 1997

To investigate the association between hepatocellular carcinema(HCC) and infection of hepatitis B virus(HBV) and hepatitis C virus(HCV) in an HBV endemic area, a case-control study of 254 patients with HCC and of 1,270 age and sex matched health control subjects was done. Among the 254 HCC patients 166(65.4%) were positive for hepatitis B surface antigen(HBsAg), 49(19.3%) were positive for HCV antibody (anti-HCV Ab). The crude odd ratio of patients with HBsAg was 36.1(95% CI :22.4-58.2) and with anti-HCV Ab was 9.0(95% CI :5.5-14.6). In an analysis, which HBsAg(-), HBcAb(-), anti-HCV Ab(-) group was chosen as referent group, odd ratio of HBsAg(+) group was 14.4(95% CI: 7.2-28.9) and of anti- HCV Ab(+) was 10.7(95% CI: 2.9-40.0). odd ratio of anti-HCV Ab(+), HBsAg(+) group and anti-HCV Ab(+), HBsAg(-), HbcAb(+) group for HCC were elevated to 27.3(95% CI : 9.0-82.9), 15.9(95% CI:7.1-35.8) respectly, The odd ratio of anti-HCV Ab(-), HBsAg(-), HBcAb(+) group was 2.4(95% CI : 1.1-5.0). These result suggested that HBV and HCV were associated with HCC. In HBV endemic area patients with HBcAb alone should be considered risk group for HCC.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.179-181
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• 2003

$F(ab`)_2$-ELISA and direct antigen coating-ELISA (DAC-ELISA) were evaluated in the detection of purified Bombyx mori nuclear polyhedrosis virus (BmNPV) and nuclear polyhedrosis virus infection in silkworm larvae inoculated with BmNPV polyhedra. Although nanogram levels of BmNPV was detected in both DAC- and $F(ab`)_2$-ELISA, similar concentrations of antigen was detected in case of F(ab’)$_2$-ELISA even at higher dilution of antibody (up to 1 : 20 K). One hundred percent nuclear polyhedrosis infection was detected 6 hrs after inoculation in BmNPV infected silkworm larvae by $F(ab`)_2$-ELISA. On the other hand, detection of 100% infection was observed only three days after inoculation in DAC-ELISA. In this study, it was observed $F(ab`)_2$-ELISA was more sensitive than DAC-ELISA in the detection of purified BmNPV as well as nuclear polyhedrosis infection in silkworm larvae.

• Journal of the Korea Society of Computer and Information
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• v.25 no.1
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• pp.13-19
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• 2020

In this paper, we propose a multiplexer based scheme that performs modular AB² multiplication using redundant basis over finite field. Then we propose an efficient multiplexer based semi-systolic AB² multiplier using proposed scheme. We derive a method that allows the multiplexers to perform the operations in the cell of the modular AB² multiplier. The cell of the multiplier is implemented using multiplexers to reduce cell latency. As compared to the existing related structures, the proposed AB² multiplier saves about 80.9%, 61.8%, 61.8%, and 9.5% AT complexity of the multipliers of Liu et al., Lee et al., Ting et al., and Kim-Kim, respectively. Therefore, the proposed multiplier is well suited for VLSI implementation and can be easily applied to various applications.

• Journal of the Korea Society of Computer and Information
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• v.25 no.1
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• pp.37-43
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• 2020

In this paper, we propose an efficient AB² multiplication algorithm using SPB(shifted polynomial basis) over finite fields. Using the feature of the SPB, we split the equation for AB² multiplication into two parts. The two partitioned equations are executable at the same time, and we derive an algorithm that processes them in parallel. Then we propose an efficient semi-systolic AB² multiplier based on the proposed algorithm. The proposed multiplier has less area-time (AT) complexity than related multipliers. In detail, the proposed AB² multiplier saves about 94%, 87%, 86% and 83% of the AT complexity of the multipliers of Wei, Wang-Guo, Kim-Lee, Choi-Lee, respectively. Therefore, the proposed multiplier is suitable for VLSI implementation and can be easily adopted as the basic building block for various applications.

• Journal of the Korean Chemical Society
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• v.43 no.4
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• pp.393-400
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• 1999

Dendritic carbosilanes based on hyperbranched polycarbosilanes as core molecule have been prepared The core molecules were obtained by the use of hydrosilation of $HSiMe_{3-n}$$(CH_2CH=CH_2)_n$(n=2; $AB_2$,3;$AB_3$type). The hyperbranched core $AB_2\;and\; AB_3$ type polymers were generated to higher molecular dendritic carbosilanes Gn+1 by the use of hydrosilation and alkenylation sequence. The Gn+2P generations were not obtained as unified molecules by the use of hydrosilation with $HSiMeCl_2$. Gn and Gn+1 type polymers were produced to polysilol by the reaction of 9-BBN and alkali medium oxidation of hydroborated compounds. The degree for reaction has been controlled by the NMR spectroscopy.