N₂/ CH₄가스비에 따른 Hydrogenated Amorphous Carbon Nitride 박막의 특성

장홍규(H. K. Jang),김근식(G. S. Kim),황보상우(S. W. Whangbo),이연승(Y. S. Lee),황정남(C. N. Whang),유영조(Y. Z. Yoo),김효근(H. G. Kim) 한국진공학회(ASCT) 1998 Applied Science and Convergence Technology Vol.7 No.3

DC saddle-field-plasma-enhanced chemical-vapor deposition(PECVD) 장치를 이용하여 상온에서 p-type Si (100) 기판위에 hydrogenated amorphous carbon nitride [a-C:H(N)]박막을 증착하였다. 원료가스인 CH₄과 N₂의 전체압력은 90 mTorr로 고정하고 N₂/CH₄비를 0에서 4까지 변화하면서 제작한 a-C:H(N) 박막의 미세 구조의 변화를 연구하였다. 진공조의 도달 진공도는 1×10^(-6) Torr이고, 본 실험시 CH₄+N₂가스의 유량은 5 sc㎝으로 고정하고 배기량을 조절하여 진공조의 가스 압력을 90 mTorr로 고정하였으며 기판에 200 V의 직류 bias 전압을 인가하였다. α-step과 X-ray photoelectron spectroscopy(XPS)를 이용한 분석결과 N₂/CH₄비가 0에서 0.5로 증가함에 따라 박막 두께는 4840 Å에서 2600 Å으로 급격히 감소하였으며, 박막내의 탄소에 대한 질소함유량(N/C비)는 N₂/CH₄비가 4일때 최대 0.25로 증가하는 것을 확인하였다. 또한 XPS 스펙트럼의 fitting 결과 N₂/CH₄비가 증가할수록 CN결합이 증가하였다. Fourier Transformation Infrared (FT-IR) 분석결과 N₂/CH₄비가 증가함에 따라 박막내의 C-H 결합은 감소하고, N-H, C≡N 결합은 증가하였다. Optical bandgap 측정 결 과 N₂/CH₄비가 0에서 4로 증가함에 따라 a-C:H(N)박막의 bandgap 에너지는 2.53 eV에서 2.3 eV로 감소하는 것을 확인하였다. Hydrogenated amorphous carbon nitride[a-C:H(N)] films were deposited on p-type Si(100) at room temperature with substrate bias voltage of 200 V by DC saddle-field plasma-enhanced chemical vapor deposition. Effects of the ratio of N₂to CH₄(N₂/CH₄), in the range of 0 and 4 on such properties as optical properties, microstucture, relative fraction of nitrogen and carbon, etc. of the films have been investigated. The thickness of the a-C:H(N) film was abruptly decreased with the addition of nitrogen, but at N₂/CH₄> 0.5, the thickness of the film gradually decreased with the increase of the N₂/CH₄. The ratio of N to C(N/C) of the films was saturated at 0.25 with the increase of N₂/CH₄. N-H, C≡N bonds of the films increased but C-H bond decreased with the increase of N₂/CH₄. Optical band gap energy of the film decreased from 2.53 eV deposited with pure methane to 2.3 eV at the ratio of N₂/CH₄=4.

소 c-KIT Receptor 유전자의 다형성에 관한 연구

장요순,김태헌,윤두학,박응우,이혜원,이학교,정일정 한국동물자원과학회 2002 한국축산학회지 Vol.44 No.6

소의 흰 반점 관련 후보유전자로 c-KIT receptor 유전자를 선정하여, c-KIT receptor 유전자내의 변이를 탐색하고 변이가 흰반점 표현형과 연관성이 있는지를 분석하였다. 한우, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin 및 Simmental 등 8개 품종의 DNA 시료를 사용하여 c-KIT receptor 유전자의 intron 6번 영역에서 다형성을 조사하고 분석하였다. c-KIT receptor 유전자의 intron 6번 영역에서는 4개의 염기치환이 발견되어, MspⅠ, BsrBⅠ 및 NdeⅠ 제한효소를 이용하여 PCR-RFLP 분석을 실시하였다. Intron 6번을 포함하는 영역의 PCR 산물 크기는 2,440 bp 이었다. MspⅠ다형성은 PCR-RFLP 분석 결과 3개의 대립유전자가 존재하였으며, 한우품종에서는 3개의 대립유전자 모두가 발견되었고, CC 형태이 유전자형을 제외한 5개의 유전자형 (AA, AB, AC, BC 및 BB)을 확인하였다. Angus, Brown Swiss, Hereford, Holstein 및 Simmental 품종에서는 A 대립유전자만을 갖는 것으로 조사되었고, 한우는 44%만 AA 유전자형을 나타내었다. BsrBⅠ 다형성은 2개의 대립유전자로서 3개의 유전자형이 나타나는 것을 확인하였으며, Charolais 및 Hereford 품종이 다른 소 품종에 비하여 A 대립유전자의 빈도가 높게 나타났다. NdeⅠ 다형성을 분석한 결과 Brown Swiss 품종에서는 NdeⅠ에 의해 절단되는 형태인 A 대립유전자만 관찰되었으며, Holstein 품종은 92%, Simmental 품종은 72%가 절단되는 형태를 나타내어, 모색이 흰색을 띠는 소 품종에서 절단되는 형태가 많았다. 소 c-KIT receptor 유전자의 intron 6번 영역에서 확인된 4개의 염기치환은 품종에 따라 다른 빈도를 보였으나, 이들 염기치환과 흰 반점과의 연관성에 대한 증거는 발견하지 못하였다. 그러므로 소의 흰 반점과 c-KIT receptor 유전자 내의 변이와의 관련성은 다른 영역에 대한 추가적인 분석과, 이미 보고된 다른 모색관련 유전자의 다형성과의 연관성 분석 등과 같은 연구가 필요한 것으로 판단된다. We considered KIT gene as a candidate gene for the white-spotting pattern in cattle. This study was carried out to detect genetic variation of c-KIT receptor gene and to investigate association between the mutation and the white-spotting pattern in cattle. PCR-RFLP analysis within intron 6 of c-KIT receptor gene were performed with 8 cattle breeds including Hanwoo, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin and Simmental. When PCR product of approximately 2,440 bp including intron 6 of c-KIT receptor gene was sequenced, four nucleotide substitutions were found within intron 6 of the bovine c-KIT receptor gene. In PCR-RFLP analysis, three alleles (A, B and C), two alleles (A and B) and two alleles (A and B) at each locus were identified by Msp Ⅰ, BsrBⅠ and NdeⅠ, respectively. Although frequencies of allele at each locus were different among cattle breeds, we could not get any evidence related with white or white spotting phenotypes in these mutations on intron 6 of c-KIT receptor gene. However, we can not entirely exclude the possibility that c-KIT receptor gene is responsible for white spotting phenotype in cattle. Thus, further studies need to detect other mutations in c-KIT receptor gene and to test association of those mutations and coat color phenotypes in cattle.

Role of Leu188 in the Fatty Acid Hydroxylase Activity of CYP102A1 from Bacillus megaterium

Jang, H.H.,Shin, S.M.,Ma, S.H.,Lee, G.Y.,Joung, Y.H.,Yun, C.H. Elsevier 2016 Journal of molecular catalysis Enzymatic Vol.133 No.-

<P>P450 BM3 (CYP102A1) from Bacillus megaterium catalyzes the subterminal hydroxylation of fatty acids with 12-22 carbons at the omega-1, omega-2 and omega-3 positions. Several amino acids located at the substrate channel and active sites are known to be important for the catalytic activity of CYP102A1. The L188 residue at the C-terminus of alpha-helix F undergoes a large shift upon substrate binding and has frequently been found in different combinations of multiple mutations showing enhanced and altered activities. In this study, we examined the role of the L188 residue by comparing the catalytic activities of wild-type CYP102A1 and 19 mutants of L188. The mutants were made with site-directed mutagenesis and functionally expressed in Escherichia coll. The enzymatic properties of the mutants for a set of fatty acids (C-10-C-16) were compared to the properties of the wild-type. L188Q and L188 P mutants showed especially strong increases in hydroxylase activity toward C-10-C-13 fatty acids, although they did not have activity changes for C-14-C-16 fatty acids. Although most mutants showed very similar overall hydroxylation rates for myristic acid, 14 mutants showed apparent changes in the regioselectivity of hydroxylation with a preference for the omega-3 position over the omega-1 position. A possible role for the L188 residue has been discussed in the context of the structure and function of CYP102A1. (C) 2016 Elsevier B.V. All rights reserved.</P>

Experimental infection of mandarin duck with highly pathogenic avian influenza A (H5N8 and H5N1) viruses

Kang, H.M.,Lee, E.K.,Song, B.M.,Heo, G.B.,Jung, J.,Jang, I.,Bae, Y.C.,Jung, S.C.,Lee, Y.J. Elsevier Scientific Pub. Co 2017 Veterinary microbiology Vol.198 No.-

<P>A highly pathogenic avian influenza (HPAI) H5N8 virus was first detected in poultry and wild birds in South Korea in January 2014. Here, we determined the pathogenicity and transmissibility of three different clades of 1-15 viruses in mandarin ducks to examine the potential for wild bird infection. H5N8 (Glade 2.3.4.4) replicated more efficiently in the upper and lower respiratory tract of mandarin ducks than two previously identified H5N1 virus clades (clades 2.2 and 2.3.2.1). However, none of the mandarin ducks infected with H5N8 and H5N1 viruses showed severe clinical signs or mortality, and gross lesions were only observed in a few tissues. Viral replication and shedding were greater in H5N8-infected ducks than in H5N1-infected ducks. Recovery of all viruses from control duck in contact with infected ducks indicated that the highly pathogenic H5 viruses spread horizontally through contact. Taken together, these results suggest that H5N8 viruses spread efficiently in mandarin ducks. Further studies of pathogenicity in wild birds are required to examine possible long-distance dissemination via migration routes. (C) 2016 Elsevier B.V. All rights reserved.</P>

GENEDIA Multi Influenza Ag Rapid Test for detection and H1, H3, and H5 subtyping of influenza viruses

Jang, J.W.,Ko, S.Y.,Byoun, M.S.,Sung, H.W.,Lim, C.S. Elsevier Science 2015 Journal of clinical virology Vol.73 No.-

Background: Rapid identification and subtype determination of influenza virus is important in managing infected patients. Rapid influenza diagnostic tests (RIDTs) are widely used in this manner, but most can only detect influenza A and B viruses without subtyping. A new RIDT, GENEDIA Multi Influenza Ag Rapid Test (GENEDIA), was developed for detection of influenza A and B viruses and also subtyping of influenza A to H1, H3, H5 which has not been possible with other RIDTs. Objectives: Assess the performance of GENEDIA. Study design: Nasopharyngeal swabs were collected from 274 clinically suspected patients (influenza A/H1N½009 (n=50), influenza A/H3 (n=50), influenza B (n=73) and influenza-negative (n=101)) and analyzed with the real-time RT-PCR, GENEDIA, SD Bioline Influenza Ag, and Alere BinaxNow Influenza A&B Card. Also, 46 fecal specimens (H5N2 (n=3), H5N3 (n=3)) of spot-billed duck were analyzed with RT-PCR and GENEDIA. Results: Compared to real-time RT-PCR, the sensitivities of GENEDIA, SD Bioline Influenza Ag, and Alere BinaxNow Influenza A&B Card were 73.0%, 57.0%, 58.0% for influenza A, respectively, and 68.5%, 65.8%, 57.5% for influenza B, respectively. Specifically, the sensitivity of GENEDIA was 70.0% for influenza A/H1N½009 and 76.0% for influenza A/H3. From the avian influenza samples, GENEDIA detected all six H5 subtype without any cross-reactions. Conclusion: The GENEDIA Multi Influenza Ag Rapid Test was sensitive in detecting influenza viruses compared with other commercial RIDTs and also useful for rapid subtype determination of influenza A.

Conduritol F, the discriminant marker between C. wilfordii and C. auriculatum by ¹H NMR spectroscopy

Jang, H.S.,Jeong, B.,Choi, S.Y.,Jang, G.H.,Park, K.C.,Kwon, Y.S.,Yang, H. Academic Press 2017 Microchemical Journal Vol. No.

<P>Quantitative H-1 nuclear magnetic resonance (qNMR) spectroscopy is a powerful and versatile technique to enable the absolute quantification of specific components in a mixture with excellent reproducibility and robustness. In the present study, qNMR analysis was applied to conduritol F, a chemical marker with the potential to distinguish between C wilfordii and C auriculatum. We found that the signals of H-5 and H-6 of conduritol F were well-separated from others with purities sufficient to be used to distinguish between C wilfordii and C. auriculatum. This simple methodology can be applied to identify one or two species in products or powdered herbs widely distributed in the markets. (C) 2017 Elsevier B.V. All rights reserved.</P>

Gut-Specific Delivery of T-Helper 17 Cells Reduces Obesity and Insulin Resistance in Mice

Hong, C.P.,Park, A.,Yang, B.G.,Yun, C.H.,Kwak, M.J.,Lee, G.W.,Kim, J.H.,Jang, M.S.,Lee, E.J.,Jeun, E.J.,You, G.,Kim, K.S.,Choi, Y.,Park, J.H.,Hwang, D.,Im, S.H.,Kim, J.F.,Kim, Y.K.,Seoh, J.Y.,Surh, C. Elsevier North Holland [etc.] 2017 Gastroenterology Vol.152 No.8

<P>BACKGROUND & AIMS: Obesity and metabolic syndrome have been associated with alterations to the intestinal microbiota. However, few studies examined the effects of obesity on the intestinal immune system. We investigated changes in subsets of intestinal CD4(+) T-helper (T-H) cells with obesity and the effects of gut-tropic T(H)17 cells in mice on a high-fat diet (HFD). METHODS: We isolated immune cells from small intestine and adipose tissue of C57BL/6 mice fed a normal chow diet or a HFD for 10 weeks and analyzed the cells by flow cytometry. Mice fed a vitamin A-deficient HFD were compared with mice fed a vitamin A-sufficient HFD. Obese RAG1-deficient mice were given injections of only regulatory T cells or a combination of regulatory T cells and T(H)17 cells (wild type or deficient in integrin beta 7 subunit or interleukin 17 [IL17]). Mice were examined for weight gain, fat mass, fatty liver, glucose tolerance, and insulin resistance. Fecal samples were collected before and after T cell transfer and analyzed for microbiota composition by metagenomic DNA sequencing and quantitative polymerase chain reaction. RESULTS: Mice placed on a HFD became obese, which affected the distribution of small intestinal CD4(+) T-H cells. Intestinal tissues from obese mice had significant reductions in the proportion of T(H)17 cells but increased proportion of T(H)1 cells, compared with intestinal tissues from nonobese mice. Depletion of vitamin A in obese mice further reduced the proportion of T(H)17 cells in small intestine; this reduction correlated with more weight gain and worsening of glucose intolerance and insulin resistance. Adoptive transfer of in vitro-differentiated gut-tropic T(H)17 cells to obese mice reduced these metabolic defects, which required the integrin beta 7 subunit and IL17. Delivery of T(H)17 cells to intestines of mice led to expansion of commensal microbes associated with leanness. CONCLUSIONS: In mice, intestinal T(H)17 cells contribute to development of a microbiota that maintains metabolic homeostasis, via IL17. Gut-homing T(H)17 cells might be used to reduce metabolic disorders in obese individuals.</P>

Regioselective C-H hydroxylation of omeprazole sulfide by Bacillus megaterium CYP102A1 to produce a human metabolite

Jang, H. H.,Ryu, S. H.,Le, T. K.,Doan, T. T.,Nguyen, T. H.,Park, K. D.,Yim, D. E.,Kim, D. H.,Kang, C. K.,Ahn, T. Springer Science + Business Media 2017 Biotechnology letters Vol.39 No.1

<P>A highly efficient synthesis of 5'-OH omeprazole sulfide was developed using CYP102A1 from Bacillus megaterium as a biocatalyst.</P>

Single-tube nested PCR assay for the detection of avian botulism in cecal contents of chickens

Jang, I.,Lee, J.I.,Kwon, Y.K.,Kang, M.S.,Kim, H.R.,Park, J.Y.,Lee, S.H.,Lee, H.S.,Bae, Y.C. Academic Press 2015 Anaerobe Vol.35 No.2

This paper describes a novel diagnostic method for the detection of avian botulism caused by Clostridium botulinum type C and C/D, using single-tube nested PCR assay. This assay was developed to overcome the disadvantages of bioassays used in experiments with mice. Three primer pairs including an antisense primer were designed to target the N-terminal of the toxin gene from C. botulinum types C and C/D. The specificity of the PCR assay was confirmed by using 33 bacterial strains and chicken cecal contents from farms that experienced botulism outbreaks. The detection limit for purified DNA was 1.1 fg/μl, and for bacterial spores was 4.3 spores/200 mg of cecal contents. While checking for specificity of the PCR assay, the reactions with the templates form C. botulinum type C and C/D which were tested became positive, but the rest of the reactions turned negative. However, the results for all clinical samples (n = 8) were positive. The PCR assay results for cecal samples obtained from 300 healthy chickens (150 Korean native chickens and 150 broilers) were all negative. This assay is rapid and straightforward and evades ethical issues associated with mouse bioassay. Moreover, it is more economical than real-time PCR.

Growth behavior and improved water-vapor-permeation-barrier properties of 10-nm-thick single Al₂O₃ layer grown via cyclic chemical vapor deposition on organic light-emitting diodes

Park, C.Y.,An, J.S.,Jang, H.J.,Lee, J.H.,Choi, B.H. Elsevier Science 2014 Organic Electronics Vol.15 No.8

We have investigated the growth behavior and water vapor permeation barrier properties of cyclic chemical vapor deposition (C-CVD)-grown 10-nm-thick single layer of Al<SUB>2</SUB>O<SUB>3</SUB>. Al<SUB>2</SUB>O<SUB>3</SUB> layers grown by C-CVD showed a high density of 3.298g/cm<SUP>3</SUP> and were amorphous without grain boundaries. A deposition rate of 0.46nm/cycle was obtained. The C-CVD system was self-limiting, as in the case of atomic layer deposition, which enables precise control of the thickness of the Al<SUB>2</SUB>O<SUB>3</SUB> layer. A water vapor transmission rate of 1.51x10<SUP>-5</SUP>(g/m<SUP>2</SUP>)/day was obtained from a Ca degradation test performed at 85<SUP>o</SUP>C and 85% relative humidity. Moreover, the performance of organic light-emitting diodes, passivated by a C-CVD-grown 10-nm-thick Al<SUB>2</SUB>O<SUB>3</SUB> single layer, was not affected after 24,000h of turn-on time; this is strong evidence that C-CVD-grown Al<SUB>2</SUB>O<SUB>3</SUB> layers effectively prevent water vapor from diffusing into the active organic layer.