• Journal of Integrative Natural Science
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• v.2 no.1
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• pp.18-23
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• 2009

This minireview provides the chosen examples of our recent discoveries in the polymerization of hydrosilanes, dihydrosilole, lactones, and vinyl derivatives using various catalysts. Hydrosilanes and lactones copolymerize to give poly(lactone-co-silane)s with $Cp_2MCl_2$/Red-Al (M = Ti, Zr, Hf) catalyst. Hydrosilanes (including dihydrosilole) reduce noble metal complexes (e.g., $AgNO_3$, $Ag_2SO_4$, $HAuCl_4$, $H_2PtCl_6$) to give nanoparticles along with silicon polymers such as polysilanes, polysilole, polysiloxanes (and silicas) depending on the reaction conditions. Interestingly, phenylsilane dehydrocoupled to polyphenylsilane in the inert nitrogen atmosphere while phenylsilane dehydrocoupled to silica in the ambient air atmosphere. $Cp_2M/CX_4$ (M = Fe, Co, Ni; X = Cl, Br, I) combination initiate the polymerization of vinyl monomers. In the photopolymerization of vinyl monomers using $Cp_2M/CCl_4$ (M = Fe, Co, Ni), the photopolymerization of MMA initiated by $Cp_2M/CCl_4$ (M = Fe, Co, Ni) shows while the polymerization yield decreases in the order $Cp_2Fe$ > $Cp_2Ni$ > $Cp_2Co$, the molecular weight decreases in the order $Cp_2Co$ > $Cp_2Ni$ > $Cp_2Fe$. For the photohomopolymerization and photocopolymerization of MA and AA, the similar trends were observed. The photopolymerizations are not living. Many exciting possibilities remain to be examined and some of them are demonstrated in the body of the minireview.

• Journal of the Microelectronics and Packaging Society
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• v.12 no.1 s.34
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• pp.47-52
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• 2005

Worldwide movement for prohibition of Pb usage drives imminent implementation of Pb-free solders in microelectronic packaging industry. Reliability information of Pb-free solders has not been completely constructed yet. One of the potential reliability concerns of Pb-free solders is allotropic transformation of Sn known as tin pest. Volume increase during the formation of tin pest could deteriorate the reliability of solder joints. It was also reported that the addition of soluble elements (i.e. Pb, Bi, and Sb) into Sn can effectively suppress the tin pest. However, the mechanical properties of the tin pest resistant alloys have not been studied in detail. In this study, lap shear creep test was conducted with Sn and Sn-0.7Cu based solder alloys doped with minor amount of Bi or Sb. Shear strain rates of the alloy were generally higher than those of Sn-3.5Ag based alloys. Rupture strains and corresponding Monkman- Grant products were largest for Sn-0.5Bi alloy and smallest for Sn-0.7Cu-0.5Sb alloy. Rupture surface Sn-0.5Bi alloy showed highly elongated $\beta$-Sn globules necked to rupture by shear stresses, while elongation of $\beta$-Sn globules of Sn-0.7Cu-0.5Sb alloy was relatively smaller.

• Biomedical Science Letters
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• v.5 no.1
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• pp.1-10
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• 1999

This study was attempted to generate a monoclonal antibody against human $\alpha$-fetoprotein (AFP) and to produce an immunoassay, recognizing AFP in plasma and amniotic fluid. AFP was purified from human amniotic fluid and used to immunize mice. Spleens were taken from the mice and the cells were fused with mouse myeloma cells (Sp2/0-Ag-14) for the production of monoclonal antibodies by employing the hybridoma technology. As a result, a hybridoma cell line producing anti-AFP monoclonal antibody was cloned out and designated as MabF22. From isotyping analysis, it was found that monoclonal antibody MabF22 was IgG type with IgG1 heavy chain and k light chain. The binding specificity of MabF22 was analyzed by immunoblotting as well as by ELISA. MabF22 was highly specific, reacting with only AFP-containing samples. The binding affinity was determined by ELISA (free-capture mode) and Scatchard analysis. As a result, the value of Kd was 0.8$\times$10$^{-10}$M. The validity of the MabF22 for AFP assay was examined by two kinds of ELISAs, i.e., non-competitive and competitive ELISA. Both assays revealed that MabF22 reacted well with AFP in sample in a concentration-dependent manner. Standard curve and antibody titration curve were obtained by using purified AFP and MabF22. These results indicate that the monoclonal antibody produced in this study would be useful not only for research purposes but also for further development of immune-diagnostic kit for the measurement of AEP concentration.

• Journal of Life Science
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• v.8 no.5
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• pp.582-588
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• 1998

The male reproductive system of Macrobrachium nipponense consists of a pair of lobulate testes enveloped within a mesenteric sheath extending the length of the carapace. The paired vasa deferentia originated from the mid-lateral region of each testis and extended to the genital pores at the base of the fifth walking legs. The vas deferens has four morphologically distinct regions, i.e., a short and slender proximal region, a long convoluted region, an elongate distal region and an ejaculatory duct that terminates at the genital pore. The sperm mass produced in the testes is surrounded by a basophilic matrix adjacent to the high columnar epithelium and an eosinophilic matrix adjacent to the simple columnar epithelium. The sperm cord is stored in the ejaculatory duct until it is ejaculated. Androgenic gland is found near the subterminal region of the ejaculatory duct between the muscles of the coxopodite of the last thoracic leg. The cell of the androgenic gland is about 6~8 $\mu$m in length, characterized by with extended chromatin in the large nucleus that stained weakly with hematoxylin and there is a large quantity of cytoplasm. The sperm of M. nipponense are typical of the palaemonid type, having a convex, cup shaped head and an elongated spike extending from the centre of the convex head. The spermatophore consisted of an eosinophilic matrix, a basophilic matrix and paired sperm masses which was surrounded by the basophilic matrix. It generally shows a bilaterally symmetrical structure.

• Journal of Mushroom
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• v.2 no.3
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• pp.127-139
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• 2004

Laccases are multicopper-containing enzymes which catalyze the oxidation of phenolic and nonphenolic compounds with the concomitant reduction of molecular oxygen. They often occur as isoenzymes, either constitutive or inducible, that oligomerize to multilateral complexes, what allow for penetration to the woody cell wall structure. White rot basidiomycete fungi may produce a number of laccase isoenzymes, some constitutively and others after induction. Fungal laccase is commonly induced by many ions, such as $Cu^{2+}$, $Cd^{2+}$ $Ca^{2+}$, $Li^+$, $Mn^{2+}$, $Ag^+$, $Hg^{2+}$, Mn and $Fe^{3+}$, phenolic compounds, some organic compounds, such as ethanol, isopropanol, cAMP, caffeine, p-anisidine, viscosinamide and paraquat, and nitrogens and even heat shock. A combination of Cu and pHB (p-hydroxybenzoic acid) made it possible to extend the inducible laccase activities over 30-fold. But the most effective inducer of laccase in the basidiomycete and other higher fungi is 2,5-xylidine, over 160-fold stimulation of laccase activity. The laccases are frequently encoded by gene families, as e.g. in Pycnoporus cinnabarinus, from which the lcc3-1 or the allelic form lac1 and lac3-2 have been cloned and sequenced. In the case of inducible forms the post-inductional laccase formation depends upon the synthesis of mRNA and the induction is due to the synthesis of a new protein.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.10
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• pp.1503-1508
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• 2005

The purpose of the present study was to evaluate the effect of Squalene, Alkoxy Glycerol, Batyl and Chimyl solutions on the production of nitric oxide (NO), tumor necrosis factor-alpha (TNF- $\alpha$ ) and interleukin-6 (IL-6) in RAW 264.7 macrophage cells after treatment of C.albicans. The cytotoxic effects was evaluated by the lactate dehydrogenase (LDH). All solutions did not affect on the LDH and NO production by itself. At 6th hour, the TNF- $\alpha$ and IL-6 production was not affected by each solutions. However, at 24th hour, the TNF- $\alpha$ and IL-6 production was affected by itself (p < 0.05). Each solution in the presence of C. albicans decreased the C. albicans-induced TNF- $\alpha$ and IL-6 production compared with C. albicans only (p < 0.05, p < 0.01). These results suggest that Squalene, Alkoxy Glycerol, Batyl and Chimyl solutions will increase the immune response on the C. albicans-induced damage.

• Restorative Dentistry and Endodontics
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• v.13 no.2
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• pp.221-235
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• 1988

The purpose of this study was to observe characteristic properties through the polarization curves and EMPA images from 4 different types of amalgam obtained by using the potentiostats (EG & G PARC) & EPMA (Jeol JSM-35), to investigate the degree of corrosion of each phase of amalgam on the oxidation peak, and to identify corrosion products from the corroded amalgam by use of X-ray diffractometer(Rigaku). After each amlgam alloy and Hg were triturated as the direction of the manufacturer by means of the mechanical amalgamator(Shofu), the triturated mass was inserted into the cylindrical metal mold which was 12mm in diameter and 10mm in height and was condensed by means of routine manner. The specimen was removed from the mold and stored at room temperature for about 7 days. The standard surface preparation was routinely carried out. Anodic polarization measurement was employed to compare the corrosion behaviours of the amalgams in 0.9% saline solution(pH6.8~7.0) and artificial saliva (pH6.8~7.0) at $37^{\circ}C$. The open circuit potential was determined after 30 minutes' immersion of specimen in electrolyte and the potential scan was begun at the potential of 100mV cathodic from the corrosion potential. The scan rate was 1mV/sec and the surface area of amalgam exposed to the solution was 0.64$cm^2$ for each specimen. All the potentials reported are with respect to a saturated calomel electrode (SCE). EPMA images on the determined oxidation peaks of each amalgam in artificial saliva were observed. X-ray diffraction patterns of each sample were recorded before and after polarization in artificial saliva (Aristaloy, Caulk Spherical, Dispersalloy and Tytin: at +770mV, +585mV, +8.10m V and +680m V respectively) by use of a recording diffractometer. Nickel filtered Cu $K_{{\alpha}_1}$ radiation was used and sample was scanned at $4^{\circ}(2{\theta})/min.$ from $25^{\circ}$ to $80^{\circ}$. The following results were obtained. 1. Oxidation peak potential in artificial saliva shifted to more anodic direction than that in saline solution. 2. The corrosion potential of high copper amalgam was more anodic than the potential of low copper amalgam. 3. The current density was lower in artificial saliva than in saline solution. 4. One of the corrosion products, AgCl was identified by X-ray diffraction analysis. 5. ${\gamma}_2$ phase was the most susceptible to corrosion and e phase was stable in low copper amalgam and ${\eta}$' phase and Ag-Cu eutectic were susceptible to corrosion in high copper amalgam.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.9
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• pp.1321-1327
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• 2011

The microorganism producing an invertase (E.C. 3.2.1.26) was isolated from wine and tentatively identified as Saccharomyces cerevisiae by cellular fatty acid analysis. The invertase was purified to homogeneity by ammonium sulfate precipitant, dialysis, ion-exchange chromatography on DEAE-Sephadex A-50, and gel chromatography on Sephadex G-200 from the culture supernatant of Saccharomyces cerevisiae JS59. The specific activity and the purification fold of the purified invertase were 7620.9 unit/mg protein and 13.9, respectively. The molecular weight of the purified invertase was estimated to be 38.5 kDa by SDS-PAGE. The optimum pH and temperature for the invertase activity were pH 5 and $55^{\circ}C$, respectively. The invertase activity was relatively stable at pH 4~6 and temperature $55^{\circ}C$. The activity of invertase was inhibited by $Ag^{2+}$ and $Hg^{2+}$, but on the contrary, activated by $Co^{2+}$ and $Mn^{2+}$. Michaelis constant ($K_m$) for invertase reaction in sucrose solution was 11.5 mM. TLC analysis of the products produced in sucrose solution during invertase reaction showed the progressive presence of glucose and fructose in accordance with sucrose hydrolysis.

• IMMUNE NETWORK
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• v.23 no.2
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• pp.17.1-17.16
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• 2023

Latent membrane protein 2A (LMP2A), a latent Ag commonly expressed in Epstein-Barr virus (EBV)-infected host cells, is a target for adoptive T cell therapy in EBV-associated malignancies. To define whether individual human leukocyte antigen (HLA) allotypes are used preferentially in EBV-specific T lymphocyte responses, LMP2A-specific CD8⁺ and CD4⁺ T cell responses in 50 healthy donors were analyzed by ELISPOT assay using artificial Ag-presenting cells expressing a single allotype. CD8⁺ T cell responses were significantly higher than CD4⁺ T cell responses. CD8⁺ T cell responses were ranked from highest to lowest in the order HLA-A, HLA-B, and HLA-C loci, and CD4⁺ T cell responses were ranked in the order HLA-DR, HLA-DP, and HLA-DQ loci. Among the 32 HLA class I and 56 HLA class II allotypes, 6 HLA-A, 7 HLA-B, 5 HLA-C, 10 HLA-DR, 2 HLA-DQ, and 2 HLA-DP allotypes showed T cell responses higher than 50 spot-forming cells (SFCs)/5×105 CD8⁺ or CD4⁺ T cells. Twenty-nine donors (58%) showed a high T cell response to at least one allotype of HLA class I or class II, and 4 donors (8%) had a high response to both HLA class I and class II allotypes. Interestingly, we observed an inverse correlation between the proportion of LMP2A-specific T cell responses and the frequency of HLA class I and II allotypes. These data demonstrate the allele dominance of LMP2A-specific T cell responses among HLA allotypes and their intra-individual dominance in response to only a few allotypes in an individual, which may provide useful information for genetic, pathogenic, and immunotherapeutic approaches to EBV-associated diseases.

• The Microorganisms and Industry
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• v.12 no.2
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• pp.2-13
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• 1986

Agrobacterium tumefaciens의 연구는 유전공학 시대를 맞이하여 많은 연구자들의 커다란 주목을 끌고있다. 식물세포내에 외부 유전자를 도입시키는, 확실히 믿을 수 있는 vector로 등장된 때문이다. 원래 이세균은 식물 줄기나 뿌리에 암종을 유발시키므로서 암발성 원인 구명 연구로 흥미를 끌게 되었다. 연구결과는 암발생 예방및 치료에 목적을 둠은 덩연할 것이다. 많은 약제가 시험되었으나 별로 진전을 보지 못하던중 비 원인성인 Agrobacterium radiobacter, strain 84에 의한 생물학적 방제의 성공으로 유일한 방제법을 갖게되었다. 뒤이어 암종발생 기작도 밝혀졌다. Agrobacterium의 세계는 온통 유전공학 기술로 채워져 있다. 암종발생에서 방제원리에 이르기까지 수없이 먼 옛날부터 이미 익혀오던 DNA 조작기술이었던가\ulcorner 암종을 유발시키는 agrocin84 plasmid를 갖는 비병원성 Agrobacterium을 찾아 생물학적 방제법을 확립하였다. 그후 병원성 Agrobacterium은 이에 대하여 어떻게 살아남을 것인가\ulcorner 실로 놀라운 일이라 아니할 수 있을까\ulcorner 이 병원성 Agrobacterium은 비 병원성 Agrobacterium 속에 있는 agrocin 84 plasmid을 탈취하여 자신이 agrocin84를 생성분비하며 암종 유발을 계소하여 간다. 아니면 비병원성 Agrobacterium이 병원성 Agrobacterium에게 agrocin 84 plasmid를 넘겨주었을까\ulcorner 왜 넘겨주었을까\ulcorner 공존을 위하여서일까\ulcorner 우리의 유전공학 기술은 이것을 막아줄수 있을까\ulcorner 생물학적 방제의 재성공을 위하여 논제의 연구는 왜 필요했던가\ulcorner 그 전후를 여기에 서술해 본다.닭이며 또한 제한된 지면에서 충분히 고찰하기는 어렵다. 우리나라에서 자주 거론되는 백신 및 종류에 국한하여 그 문제점과 앞으로의 전망을 고찰해 보기로 한다.ocking electrode를 제작하여 복합고분자 전해질과의 계면저항을 측정하였다.nm (1.2921eV)는 acceptor-bound exciton 인 I1(AO,X) 이고, 964.6nm(1.2853eV)는 donor-acceptor pair(DAP) 발광, 1341.9nm (0.9239eV)는 self activated(SA)에 기인하는 광발광 봉우리로 고찰되었다.가 높을수록 방출전류가 시간에 따라 급격히 감소하였다. 각 duty비에서 방출전류의 양이 1/2로 감소하는 시점을 에미터의 수명으로 볼 때 duty비 대 에미터 수명관계를 구해 높은 duty비에서 전계방출을 시킴으로써 실제의 구동조건인 낮은 duty비에서의 수명을 단시간에 예측할 수 있었다. 단속적으로 일어난 것으로 생각된다.리 폐 관류는 정맥주입 방법에 비해 고농도의 cisplatin 투여로 인한 다른 장기에서의 농도 증가 없이 폐 조직에 약 50배 정도의 고농도 cisplatin을 투여할 수 있었으며, 또한 분리 폐 관류 시 cisplatin에 의한 직접적 폐 독성은 발견되지 않았다이 낮았으나 통계학적 의의는 없었다[10.0%(4/40) : 8.2%(20/244), p>0.05]. 결론: 비디오흉강경술에서 재발을 낮추기 위해 수술시 폐야 전체를 관찰하여 존재하는 폐기포를 놓치지 않는 것이 중요하며, 폐기포를 확인하지 못한 경우와 이차성 자연기흉에 대해서는 흉막유착술에 더 세심한 주의가 필요하다는 것을 확인하였다. 비디오흉강경수술은 통증이 적고, 입원기간이 짧고, 사회로의 복귀가 빠르며, 고위험군에 적용할 수 있고, 무엇보다도 미용상의 이점이 크다는 면에서 자연기흉에 대해 유용한 치료방법임에는