The H <small>i</small> environment of counter‐rotating gas hosts: gas accretion from cold gas blobs

Chung, Aeree,Bureau, Martin,van Gorkom, J. H.,Koribalski, Bä,rbel Blackwell Publishing Ltd 2012 Monthly notices of the Royal Astronomical Society Vol.422 No.2

<P><B>ABSTRACT</B></P><P>We probe the H <SMALL>i</SMALL> properties and the gas environments of three early‐type barred galaxies harbouring counter‐rotating ionized gas: NGC 128, NGC 3203 and NGC 7332. Each system has one or more optically identified galaxy at a similar or as yet unknown redshift within a 50‐kpc projected radius. Using H <SMALL>i</SMALL> synthesis imaging data, we investigate the hypothesis that the counter‐rotating gas in these galaxies has been accreted from their neighbours. In NGC 128 and NGC 3203, we find 9.6 × 10<SUP>7</SUP> and 2.3 × 10<SUP>8</SUP> M<SUB>⊙</SUB> of H <SMALL>i</SMALL>, respectively, covering almost the entire stellar bodies of dwarf companions that appear physically connected. Both the H <SMALL>i</SMALL> morphology and kinematics are suggestive of tidal interactions. In NGC 7332, we do not find any directly associated H <SMALL>i</SMALL>. Instead, NGC 7339, a neighbour of a comparable size at about 10 kpc, is found with 8.9 × 10<SUP>8</SUP> M<SUB>⊙</SUB> of H <SMALL>i</SMALL> gas. More recently in a single dish observation, however, another group discovered a large H <SMALL>i</SMALL> structure which seems to be an extension of NGC 7339’s H <SMALL>i</SMALL> disc and also covers NGC 7332. All these observations thus suggest that H <SMALL>i</SMALL> gas is being accreted in these three galaxies from their companions, which is likely responsible for the kinematically decoupled gas component present in their central region. In particular, the dynamical friction time‐scales of the nearest neighbours with H <SMALL>i</SMALL> gas of NGC 128 and NGC 3203 are comparable to their orbital time‐scales around the counter‐rotators, several ∼10<SUP>8</SUP> yr, implying that those neighbours will likely soon merge with the primary galaxies, fuelling them with gas. NGC 7332 also appears to be in the merging process with its neighbour through the common H <SMALL>i</SMALL> envelope. Besides, we find some other potential gas donors around NGC 128 and NGC 7332: two H <SMALL>i</SMALL>‐rich galaxies with <IMG src='/wiley-blackwell_img/equation/MNR_20679_mu1.gif' alt ='inline image'/> and 2.5 × 10<SUP>9</SUP> M<SUB>⊙</SUB> at a distance of ≈67 kpc from NGC 128 and two dwarf systems with <I>M</I><SUB>HI</SUB>= 3.9 × 10<SUP>7</SUP> and 7.4 × 10<SUP>7</SUP> M<SUB>⊙</SUB> at ≲100 kpc from NGC 7332. Among the seven H <SMALL>i</SMALL> features identified in this study, three of them are associated with dwarf galaxies, two of which have only been recently identified in a blind survey, while the third one is still not catalogued at optical wavelengths. Considering the incompleteness of existing studies of the faint dwarf galaxy population both in the optical and in H <SMALL>i</SMALL>, accretion from cold gas blobs, presumably gas‐rich dwarfs, is expected to occur even more frequently than what is inferred from such cases that have been observed to date.</P>

VP2 capsid domain of the H-1 parvovirus determines susceptibility of human cancer cells to H-1 viral infection

Cho, I-R,Kaowinn, S,Song, J,Kim, S,Koh, S S,Kang, H-Y,Ha, N-C,Lee, K H,Jun, H-S,Chung, Y-H Nature America, Inc. 2015 Cancer gene therapy Vol.22 No.5

Although H-1 parvovirus is used as an antitumor agent, not much is known about the relationship between its specific tropism and oncolytic activity. We hypothesize that VP2, a major capsid protein of H-1 virus, determines H-1-specific tropism. To assess this, we constructed chimeric H-1 viruses expressing Kilham rat virus (KRV) capsid proteins, in their complete or partial forms. Chimeric H-1 viruses (CH1, CH2 and CH3) containing the whole KRV VP2 domain could not induce cytolysis in HeLa, A549 and Panc-1 cells. However, the other chimeric H-1 viruses (CH4 and CH5) expressing a partial KRV VP2 domain induced cytolysis. Additionally, the significant cytopathic effect caused by CH4 and CH5 infection in HeLa cells resulted from preferential viral amplification via DNA replication, RNA transcription and protein synthesis. Modeling of VP2 capsid protein showed that two variable regions (VRs) (VR0 and VR2) of H-1 VP2 protein protrude outward, because of the insertion of extra amino-acid residues, as compared with those of KRV VP2 protein. This might explain the precedence of H-1 VP2 protein over KRV in determining oncolytic activity in human cancer cells. Taking these results together, we propose that the VP2 protein of oncolytic H-1 parvovirus determines its specific tropism in human cancer cells.

성장단계별 농후사료 (濃厚飼料) 급여수준이 한우 육성비육우의 (育成肥育牛) 사료효율 , 산육능력 및 육질에 미치는 영향

강수원(S . W . Kang),장선식(S . S . Jang),정연후(Y . H . Chung),신기준(K . J . Shin),손용석(Y . S . Son) 한국영양사료학회 1995 韓國營養飼料學會誌 Vol.19 No.6

Farnesyl transferase 억제제인 YH3938 및 YH3945에 의한 Ras 발암원성 억제

Myung-Ju Oh(오명주),Nong Yeon Kim(김농연),Su-Eun Lim(임수은),Young-Hwa Chung(정영화),Byung H Jhun(전병학) 한국생명과학회 2010 생명과학회지 Vol.20 No.2

Ras 유전자는 30%의 인간암에서 변이가 발견되며 세 종류의 isoform, H-Ras, K-Ras 및 N-Ras로 구성되어 있다. Ras 단백질의 CAAX motif에 farnesylation과 같은 번역 후 변형은 Ras의 활성에 필수 요소이다. 본 연구에서는 새로운 farnesyl transferase 억제제인 YH3938과 YH3945의 발암원성 H-Ras, K-Ras 및 N-Ras의 작용에 대한 영향을 조사하였다. YH3938과 YH3945는 발암원성 H-Ras에 의해 형질전환된 Rat2 세포의 증식과 형태 변화를 억제하였으나 K-Ras에 대해서는 효과가 없었다. N-Ras에 대해서는 약한 영향이 있었다. H-Ras와 N-Ras에 의한 SRE promoter 활성화는 YH3938과 YH3945에 의해 억제되었으나, K-Ras에는 영향이 없었다. Ras 단백질의 bandshift 분석을 통해 YH3938은 H-Ras와 N-Ras의 번역 후 변환을 억제하였으나, K-Ras에는 영향이 없었다. YH3945는 H-Ras의 변환에만 영향이 있었다. 결론적으로 YH3938과 YH3945는 H-Ras의 farnesylation을 억제하여 그 발암원성을 억제하며, YH3938은 N-Ras 작용을 농도의존적으로 억제하며, K-ras에 대해서는 영향이 없음을 알 수 있었다. Ras genes are responsible for up to 30% of human tumor mutations and are composed of three isoforms: H-Ras, K-Ras and N-Ras. The post-translational modification of the CAAX motif of the Ras protein is essential in Ras actions. In the present study, we studied the effects of novel farnesyl transferase inhibitors (FTIs), YH3938 and YH3945, on the actions of oncogenic mutants of H-Ras, K-Ras and N-Ras. YH3938 and YH3945 completely reverted the proliferation and morphology of oncogenic H-Ras-transformed Rat2 cells, but not of oncogenic K-Ras-transformed Rat2 cells. Oncogenic N-Rastransformed Rat2 cells were slightly affected. Activation of SRE promoters by oncogenic H-Ras and N-Ras, but not by K-Ras, were inhibited by treatment with YH3938 and YH3945. Using bandshift analysis, YH3938 suppressed the processing of oncogenic H-Ras and N-Ras, but not that of oncogenic K-Ras protein. YH3945 only inhibited the processing of H-Ras. From these results, we conclude that YH3938 and YH3945 specifically inhibit actions of oncogenic H-Ras through inhibition of its farnesylation, that YH3938 also inhibits N-Ras activity in a dose-dependent manner, and that these drugs have no effect on oncogenic K-Ras activity.

성장단계별 농후사료 (濃厚飼料) 급여수준이 한우 육성빈우의 (育成牝牛) 체중변화 및 번식능력에 미치는 영향

강수원(S . W . Kang),장선식(S . S . Jang),임석기(S . K . Im),정창화(C . H . Chung),신기준(K . J . Shin) 한국영양사료학회 1996 韓國營養飼料學會誌 Vol.20 No.2

H-FUZZY SEMITOPOGENOUS PREOFDERED SPACES

Chung, S.H. Korean Mathematical Society 1994 대한수학회논문집 Vol.9 No.3

Throughout this paper we will let H denote the complete Heyting algebra ($H, \vee, \wedge, *$) with order reversing involution *. 0 and 1 denote the supermum and the infimum of $\emptyset$, respectively. Given any set X, any element of $H^X$ is called H-fuzzy set (or, simply f.set) in X and will be denoted by small Greek letters, such as $\mu, \nu, \rho, \sigma$. $H^X$ inherits a structure of H with order reversing involution in natural way, by definding $\vee, \wedge, *$ pointwise (sam notations of H are usual). If $f$ is a map from a set X to a set Y and $\mu \in H^Y$, then $f^{-1}(\mu)$ is the f.set in X defined by f^{-1}(\mu)(x) = \mu(f(x))$. Also for $\sigma \in H^X, f(\sigma)$ is the f.set in Y defined by $f(\sigma)(y) = sup{\sigma(x) : f(x) = y}$ ([4]). A preorder R on a set X is reflexive and transitive relation on X, the pair (X,R) is called preordered set. A map $f$ from a preordered set (X, R) to another one (Y,T) is said to be preorder preserving (inverting) if for $x,y \in X, xRy$ implies $f(x)T f(y) (resp. f(y)Tf(x))$. For the terminology and notation, we refer to [10, 11, 13] for category theory and [7] for H-fuzzy semitopogenous spaces.

H-Y 에 대한 단일클론 항체의 생산 및 그 이용에 관한 연구 1 . H-Y 에 대한 단일클론항체의 생산

심호섭(H . S . Shim),김재화(J . H . Kim),이병철(B . C . Lee),김종배(J . B . Kim),박홍양(H . Y . Park),정길생(K . S . Chung) 한국축산학회 1988 한국축산학회지 Vol.30 No.7

Testis supernatant, a source of H-Y, obtained from BALB/c mice was used to immunize females of same strain. B lymphocytes of mouse producing antibodies to H-Y were fused with SP2/0-Ag 14 myeloma cells and distributed to 384 wells of 96-well microtiter plates. Eighty hybridoma colonies were formed, resulting in 20.8 percent of fusion efficiency. Three strong positive wells from hybridoma colonies were selected for cloning by ELISA and two of them were also found to be positive by indirect immunofluorescence test. Twelve wells of ELISA-positive were selected after cloning and 2D45D4 clones from them were confirmed to produce monoclonal antibodies to H-Y by indirect immunofluorescence test.

H-Y 항체에 의한 토끼배의 성조절에 관한 연구 1 . 배의 발달과 형광 발현에 의한 자 웅 수정란의 분리

이창규(C . K . Lee),정구민(K . M . Chung),김수헌(S . H . Kim),임경순(K . S . Im) 한국축산학회 1990 한국축산학회지 Vol.32 No.7

Antisera to histocompatibility (H-Y) antigen were used to immunologically presume the sex of rabbit embryos. H-Y antisera were prepared in inbred SD female rat by repeated immunization of spleen cells from males of same strain. The titre of H-Y antibody in antiserum was examined by mouse sperm cytotoxicity and biological tests. Experiments applied delaying ability of development of embryos in H-Y antiserum and binding ability of FITC labelled second antibody. After culture, embryos were observed their morphological characteristics under phase contrast microscope and detected fluorescence on embryos under fluorescence microscope. After detection of fluorescence, embryos were transfered to normal medium and observed their morphological characteristics. 1. When rabbit morula were treated with H-Y antiserum only, the rate of developed and delayed embryos was 47.2 and 52.8% respectively, and the rate of non-fluorescing and fluorescing embryos was 51.4 and 48.6%, respectively. 2. When rabbit morula were cultured in H-Y antiserum followed by complement, the rate of non-fluorescing and fluorescing embryos was 53.6 and 46.4%. respectively. 3. After detection of fluorescence, the embryos were cultured in normal medium. When embryos were treated with H-Y antiserum only, the rate of arrested and developed embryos was 20.8 and 79.2% respectively. However, when embryos were treated with H-Y antiserum followed by complement, the rate of arrested and developed embryos was 42.9 and 57.1% respectively.

PHF2 histone demethylase acts as a tumor suppressor in association with p53 in cancer

Lee, K-H,Park, J-W,Sung, H-S,Choi, Y-J,Kim, W H,Lee, H S,Chung, H-J,Shin, H-W,Cho, C-H,Kim, T-Y,Li, S-H,Youn, H-D,Kim, S J,Chun, Y-S Macmillan Publishers Limited 2015 Oncogene Vol.34 No.22

Plant homeodomain finger 2 (PHF2) has a role in epigenetic regulation of gene expression by demethylating H3K9-Me2. Several genome-wide studies have demonstrated that the chromosomal region including the PHF2 gene is often deleted in some cancers including colorectal cancer, and this finding encouraged us to investigate the tumor suppressive role of PHF2. As p53 is a critical tumor suppressor in colon cancer, we tested the possibility that PHF2 is an epigenetic regulator of p53. PHF2 was associated with p53, and thereby, promoted p53-driven gene expression in cancer cells under genotoxic stress. PHF2 converted the chromatin that is favorable for transcription by demethylating the repressive H3K9-Me2 mark. In an HCT116 xenograft model, PHF2 was found to be required for the anticancer effects of oxaliplatin and doxorubicin. In PHF2-deficient xenografts, p53 expression was profoundly induced by both drugs, but its downstream product p21 was not, suggesting that p53 cannot be activated in the absence of PHF2. To find clinical evidence about the role of PHF2, we analyzed the expressions of PHF2, p53 and p21 in human colon cancer tissues and adjacent normal tissues from patients. PHF2 was downregulated in cancer tissues and PHF2 correlated with p21 in cancers expressing functional p53. Colon and stomach cancer tissue arrays showed a positive correlation between PHF2 and p21 expressions. Informatics analyses using the Oncomine database also supported our notion that PHF2 is downregulated in colon and stomach cancers. On the basis of these findings, we propose that PHF2 acts as a tumor suppressor in association with p53 in cancer development and ensures p53-mediated cell death in response to chemotherapy.

선택적 촉매 산화 반응에 의한 황화 수소의 제거 Ⅱ . TiO2 / SiO2 촉매 상에서 황화 수소의 선택적 산화 반응

천승우,박대원,우희철,홍성수,정종식 ( S . W . Chun,D . W . Park,H . C . Woo,S . S . Hong,J . S . Chung ) 한국공업화학회 1996 공업화학 Vol.7 No.4

본 연구는 H₂S를 TiO₂/SiO₂촉매상에서 산소와의 직접 산화 반응을 통해 원소 황의 형태로 제거하는 반응에 관한 것이다. 순수한 TiS₂Ti(SO₄)_2를 사용한 반응 실험과 순수한 TiO₂에 대한 주기적 온도 조작 실험 결과로부터 TiO₂는 황 회수 공정에서 사용되는 촉매의 비활성화의 주원인으로 알려진 sulfation이나 salfidation에 대해 매우 안정한 것으로 나타났다. TiO₂/SiO₂촉매에서 TiO₂의 담지량이 증가함에 따라 H₂S 전화율이 증가하였고, 원소 황의 선택도는 아주 소폭으로 감소하였다. 반응 실험결과 O₂/H₂S의 비가 증가할수록 원소 황의 선택도는 크게 감소하였다. 10 wt.% TiO₂/SiO₂ 촉매는 화학 양론비의 조성(H₂S=5 vol.% O₂=2.5 vol.%)의 반응물에 10 vol.%의 수증기를 첨가한 경우 활성과 선택도가 감소하였으나 여전히 80% 이상의 원소 황 수율을 유지하고 있었다. Selective catalytic oxidation of H₂S to elemental sulfur using TiO₂/SiO₂ catalysts was investigated in this study. The reaction test with pure TiS₂and Ti(SO₄)₂and cyclic temperature operation revealed that TiO₂had a good resistance to sulfation and sulfidation, which are known as the main cause of catalytic deactivation in sulfur recovery process. With the increase of TiO₂loading amount in Tio₂/SiO₂catalysts, the conversion of H₂S increased and the selectivity of elemental sulfur was very slightly decreased. As the ratio of O₂/H₂S increased, the selectivity to elemental sulfur was drastically decreased. In the presence of 10 vol.% water vapor to a stoichiometric mixture of H₂S and O₂(H₂S =5 vol.% O=2.5 vol.%), both activity and selectivity of 10 wt.% TiO₂/SiO₂catalyst are decreased, but it still showed more than 80% of sulfur yield.