수소 Blistering 에 미치는 외부응력의 영향, 제2부

황인환,남수우,박동석 대한금속재료학회(대한금속학회) 1981 대한금속·재료학회지 Vol.19 No.4

Blisters and internal cracks below free surface of a prestrained ASE 4340 steel were observed after hydrogen was cathodically charged in the steel. It is hypothesized that blistering which is a result of the local plastic deformation is taking place due to a modified triaxial stress state around a void in which hydrogen molecules generate gas pressure. Triaxial stress state can be modified by the external or residual stress to generate the shear component which induces the plastic deformation. It was observed that the maximum depth of cracks was increased with the amount of cold working, such as tensile, rolling, and bending deformation. To see the possible effect of the microstructural change by the cold works on the crack depth, cold worked specimens were stress-relief annealed and then hydrogen was charged. In these cases, it was observed that the crack depths did not increase as much as those of cold worked specimens with residual stress developed due to cold work. These results give a confirmation of the proposed, hypothesis.

쥐의 자궁에서 아릴썰파타아제 A의 분리 및 그 성질에 관한 연구

황인환,양철학 ( In Hwan Hwang,Chul Hak Yang ) 생화학분자생물학회 1983 BMB Reports Vol.16 No.1

Arylsulfatase A (aryl sulfate sulfohydrolase; E.C. 3. 1. 6. 1) from rat uterus was highly purified by ammonium sulfate fractionation, DEAE-cellulose chromatography, Sephadex G-200 gel filtration. Conconavalin A-Sepharose affinity chramatography, and second gel filtration on Sephadex G-200. Arylsulfatase A was separated from arylsulfatases B and Bm by DEAE-cellulose column where arylsulfatase A was eluted at 0. 2 M of NaCl linear gradient. The enzyme was purified 207-fold with 8 % recovery, but disc polyacrylamide-gel electrophoresis showed that the purified preparation was not homogeneous. Arylsulfatase A showed the anomalous time-activity relationship. The K_m and V_(mas) were 6.8 mM and 15.6 nmol/min, respectively. Arylsulfatase A had two pH optima at pH 5. 2 and 5.6 for 10 min incubation time, and these optima shifted to pH 5.0 and 5.6 with incubation time of 60 min. SO₄^(2-), PO₄₃^(2-), and PO₄^(2-) were strong inhibitors with Ki values of 4.3×10^(-3)M, 6.6×10^(-5)M, and 3.0×10^(-6)M, respectively. Pyrophosphate and Cu^(2+) ion inhibited arylsulfatase A but Mn^(2+), Ca^(2+), Co^(2+), and ascorbic acid activated the enzyme activity. Siver and Cl- ion did not affect the enzyme activity. Enzyme activity was increased to 60 ℃ for 10 min and thermally stable at 60 ℃ for 70 min with 82 % of activity. By Sephadex G-200 gel filtration the molecular weight of arylsulfatase A was 120,000 at both pH 5.0 and 7.2.

족관절 삼과 골절과 동반된 장 비골건 탈구(1예 보고)

황인환,김광열,김형천,임문섭,이지훈,조성준,Hwang, In-Hwan,Kim, Kwang-Yul,Kim, Hyung-Chun,Lim, Moon-Sup,Lee, Ji-Hoon,Cho, Sung-Jun 대한족부족관절학회 2009 대한족부족관절학회지 Vol.13 No.2

Traumatic dislocation of the peroneus longus tendon is an often unrecognized injury which has been reported to occur most commonly during sports activity. Most acute cases with early detection can be treated by simple repair of the tendon or retinaculum using one of several procedures available. Accurate treatment through a comprehensive evaluation of the ankle injury prevents suboptimal and sometimes unrecorrectable outcomes. The authors experienced concomitantly the peroneus longus tendon dislocation associated with a trimalleolar fracture of the ankle. We report this case a brief review of the literature.

쥐의 자궁에서 아릴썰파타아제 B 및 Bm의 분리 및 그 효소의 특성에 관한 연구

황인환,양철학 ( In Hwan Hwang,Chul Hak Yang ) 생화학분자생물학회 1984 BMB Reports Vol.17 No.2

Arylsulphatases B and Bm (arylsulphate sulphohydrolase; E.C. 3.1.6.1) from rat uterus were purified and characterized. Arylsulphatases B and Bm were purified 286-fold and 112-fold with an overall recovery 23% and 5.4% respectively. On disc gel electrophoresis, both final preparations of arylsulphatases B and Bm showed one protein band. These enzymes showed normal time-activity relationship with p-nitrocatechol sulphate as substrate. The K_m and V_(max) values were 2.0×10^(-3) M and 20.8 nmol/min for arylsulphatase B and 3.9×10^(-3) M and 67 nmol/min for arylsulphatase Bm, respectively. Rat uterus contained significant quantities (16∼20% of total arylsulphatase) of an anionic form of arylsulphatase B (arylsulphatase Bm). The physico-chemical properties of arylsulphatase Bm were very similar to those of arylsulphatase B with respect to pH optimum, heat stability, the types of inhibition by sulphate, sulphite and phosphate ions, molecular weight, temperature optimum, and time-activity relationship.

Purification and Characterization of Arylsulfatase A from Rat Uterus

황인환,양철학,Hwang, In-Hwan,Yang, Chul-Hak 생화학분자생물학회 1983 한국생화학회지 Vol.16 No.1

$(NH_4)_2\;SO_4$, 분획분리, DEAE-셀룰로즈 크로마토그라피, Sephadex G-200젤 여과법, Con A-Sepharose 흡착크로마토그라피 및 Sephadex G-200젤 여과법등을 이용하여 쥐의 자궁에서 아럴썰파타아제 A를 거의 순수한 상태로 정제하였다. 아랄쎌파타아제 A는 DEAE-셀룰로즈 column에 의하여 아릴썰파타아제 B와 Bm으로부터 분리되어졌고, DEAE-셀룰로즈 column으로 부터 0.2M NaCl 선형 농도증가에 의해서 흘러나왔다. 이 효소는 마지막 단계의 회수율이 8%였으며, 207배 정제되어졌으나 Disc-폴리아크릴아마이드 젤 영동법에 의하여 단일 단백질로 정제되지는 않았다. 아릴쎌파다아제 A는 비정상적인 시간에 따른 활동도 곡선을 나다냈다. 아릴썰파타아제 A는 $37^{\circ}C$에서 10 분동안의 반응에서는 pH 적정점은 pH 5.2와 pH 5.6이었는데, 60분 동안의 반응에서는 pH 5.0과 pH 5.6으로 바뀌어졌다. ${SO_4}^{2-}$, ${SO_3}^{2-}$ 및 ${PO_4}^{2-}$는 강한 방해제로서 작용하며 그들의 Ki값은 각각 $4.3{\times}10^{-3}M$, $6.6{\times}10^{-5}M$ 및 $3.0{\times}10^{-5}M$이었다. $P_2{O_7}^{2-}$와 $Cu^{2+}$ 이온은 아릴쎌파다아제 A 활성도를 방해하였으나 $Mn^{2+}$, $Co^{2+}$, $Ca^{2+}$와 ascorbic acid는 활성도를 오히려 증가시켰다. 반면에 $Ag^+$와 $Cl^-$이온은 효소의 활동에 전혀 영향을 미치지 않았다. 효소의 활성도는 $60^{\circ}C$까지 온도의 증가에 따라 계속 증가되 었으며 70분 동안 $60^{\circ}C$에서 82%의 활동도를 유지하였다. Sephadex G-200젤 여과법에 의하여 아랄쎌파타아제 A의 분자량은 pH 5.0 과 pH 7.2에서 모두 120,000 daltons으로 나타났다. Arylsulfatase A (aryl sulfate sulfohydrolase; E.C. 3.1.6.1) from rat uterus was highly purified by ammonium sulfate fractionation, DEAE-cellulose chromatography, Sephadex G-200 gel filtration. Conconavalin A-Sepharose affinity chramatography, and second gel filtration on Sephadex G-200. Arylsulfatase A was separated from arylsulfatases B and Bm by DEAE-cellulose column where arylsulfatase A was eluted at 0.2 M of NaCl linear gradient. The enzyme was purified 207-fold with 8% recovery, but disc polyacrylamide-gel electrophoresis showed that the purified preparation was not homogeneous. Arylsulfatase A showed the anomalous time-activity relationship. The $K_m$ and $V_{max}$ were 6.8 mM and 15.6 nmol/min, respectively. Arylsulfatase A had two pH optima at pH 5.2 and 5.6 for 10 min incubation time, and these optima shifted to pH 5.0 and 5.6 with incubation time of 60 min. ${SO_4}^{2-}$, ${SO_3}^{2-}$, and ${PO_4}^{2-}$ were strong inhibitors with Ki values of $4.3{\times}10^{-3}M$, $6.6{\times}10^{-5}M$, and $3.0{\times}10^{-5}M$, respectively. Pyrophosphate and $Cu^{2+}$ ion inhibited arylsulfatase A but $Mn^{2+}$, $Co^{2+}$, $Ca^{2+}$, and ascorbic acid activated the enzyme activity. Siver and $Cl^-$ ion did not affect the enzyme activity. Enzyme activity was increased to $60^{\circ}C$ for 10 min and thermally stable at $60^{\circ}C$ for 70 min with 82% of activity. By Sephadex G-200 gel filtration the molecular weight of arylsulfatase A was 120,000 at both pH 5.0 and 7.2.

Arylsulphatases B and Bm from Rat Uterus: Their Purifications and Characterizations

황인환,양철학,Hwang, In-Hwan,Yang, Chul-Hak 생화학분자생물학회 1984 한국생화학회지 Vol.17 No.2

아릴썰파타아제 B 및 Bm(아렬썰페이트 썰포하이드롤라아제 ; E.C.3.1.6.1)이 쥐의 자궁으로부터 분리되고 그 특성이 연구되었다. 아릴썰파타아제 B는 286배로 정제되고 그 수율은 23%이었으며 Bm은 112배 정제되고 그 수율은 5.4%이었다. 통판 전기영동에 의해 마지막으로 얻어진 아릴썰파타아제 B 및 Bm은 하나의 단백질 띠로 나타났다. 이 효소들은 파라-나이트로카테콜썰페이트를 기질로 사용했을 때 정상적인 시간-활동도의 관계를 나타냈다. $K_m$과 $V_{max}$ 값은 아릴썰파타아제 B가 $2.0{\times}10^{-3}M$ 및 20.8 nmol/min 이었고 아릴썰파타아제 Bm은 $3.9{\times}10^{-3}M$ 및 67 nmol/min 이었다. 쥐의 자궁은 상당한 양의 음성형의 아릴썰파타아제 B(즉 아릴썰파타아제 Bm)를 함유하고 있었다. 아릴썰파타아제 Bm은 물리화학적 성질 가운데서 pH 적정점, 열에 대한 안정도, 썰페이트, 썰파이트 및 포스페이트에 대한 방해작용이나 시간-활동도의 관계에 있어 아릴썰파타아제 B와 거의 비슷한 결과를 나타냈다. Arylsulphatases B and Bm (arylsulphate sulphohydrolase; E.C.3.1.6.1) from rat uterus were purified and characterized. Arylsulphatases B and Bm were purified 286-fold and 1I2-fold with an overall recovery 23% and 5.4%, respectively. On disc gel electrophoresis, both final preparations of arylsulphatases B and Bm showed one protein band. These enzymes showed normal time-activity relationship with p-nitrocatechol sulphate as substrate. The $K_m$ and $V_{max}$ values were $2.0{\times}10^{-3}\;M$ and 20.8 nmol/min for arylsulphatase Band $3.9{\times}10^{-3}\;M$ and 67 nmol/min for arylsulphatase Bm, respectively. Rat uterus contained significant quantities (16~20% of total arylsulphatase) of an anionic form of arylsulphatase B (arylsulphatase Bm). The physico-chemical properties of arylsulphatase Bm were very similar to those of arylsulphatase B with respect to pH optimum, heat stability, the types of inhibition by sulphate, sulphite and phosphate ions, molecular weight, temperature optimum, and time-activity relationship.

'AKR2 유전자' 통해 엽록체 생성 기원 밝혔다

황인환,Hwang, In-Hwan 한국과학기술단체총연합회 2008 과학과 기술 Vol.41 No.2

이동 트랜잭션의 중복 데이터에 대한 낙관적 일치성 제어 기법 ( Optimistic Consistency Control of Replicated Data for Mobile Transaction : OCC / MT )

황인환,이종현 대한전자공학회 1997 대한전자공학회 학술대회 Vol.1997 No.1

사무용 건물의 에너지 절약설계수법

황인환,Hwang, In-Hwan 한국설비기술협회 1992 설비 : 공조ㆍ냉동ㆍ위생 Vol.9 No.7

조현병 환자의 입원 치료시 약물처방 경향의 변화 : 일 대학병원에서 1996~2000년과 2006~2010년의 차이 비교

황인환,김대호,오대영,Hwang, In-Hwan,Kim, Daeho,Oh, Dae-Young 대한생물정신의학회 2014 생물정신의학 Vol.21 No.2

Objectives Previous literature on the prescription change among patients with schizophrenia mainly focused on antipsychotics. This study investigated chronological change in the patterns of discharge medication among inpatients with schizophrenia at a psychiatric inpatient unit of a university-affiliated hospital. Methods All admission records at a psychiatric unit of Hanyang University Guri Hospital with discharge diagnosis of schizophrenia during two different five-year time frames (1996-2000 and 2006-2010) were reviewed including the demographic and clinical data and discharge medications. The data were gathered from a total of 207 patients (95 in 1990s and 112 in 2000s). Results The frequency in use of atypical antipsychotics (p < 0.01), antidepressants (p < 0.05), beta-blockers (p < 0.01), and benzodiazepine (p < 0.01) was significantly higher in 2000s. Anticholinergic drugs were less likely used in 2000s (p < 0.01). We did not find significant differences in the equivalent dose of antipsychotic drugs, the use of mood stabilizers and cholinergic drugs between two time frames. Conclusions Increased proportion of atypical antipsychotics and decreased use of anti-parkinsonian drugs are in line with literature. Our results show that more diverse classes of psychotic medications are used for schizophrenia in recent years. It is likely that psychiatrists are becoming more conscious of negative symptoms, anxiety, and depression in the pharmacotherapy of schizophrenia as well as positive symptoms of the illness.