Trypsin inhibitor 결여 大豆品種의 탐색 및 그의 遺傳育種學的 硏究 : I. Trypsin inhibitors의 전기영동 감정방법에 의한 대두 품종별 비교 및 DEAE-cellulose에 의한 분리 I. Soybean trypsin inhibitors: electrophoretic differences among varieties and their fractionation on DEAE-cellulose

金秀一,李錫河,李弘石,文亢植,羅志英 서울大學校 農科大學 1985 서울대농학연구지 Vol.10 No.1

대두의 단백추출액을 polyacrylamide gel 전기영동에 의하여 분류하고 trypsin inhibitor (T.I) band를 동정하였다. T.I. band는 전기영동한 gel을 trypsin으로 가수분해하거나 추출액에 trypsin을 처리한 후 전기영동하거나 발색기질을 이용하여 gel을 착색시키거나 또는 gel slice의 T.I.activity를 측정하는 등 네 가지 방법을 사용하여 검정하였다. 이중 추출액을 trypsin으로 처리한 후 전기영동하는 방법과 gel slice의 T.I.activity를 측정하는 방법이 가장 적합하였으며 두 방법의 결과를 비교하여 T.I.band를 검정하는 것이 보다 확실하였다. Sephadex G-75 Chromatography 에서 물로 추출한 대두 단백질은 3 fraction으로 분리하였고 T.I.activity는 제 2 fraction 에만 나타났다. Kunitz 및 Bowman-Birk형 inhibitor는 DEAE-cellulose column chromatography로 분리하였다. Kunitz형은 5개의 fraction으로, Bowman-birk형은 4개의 fraction으로 분리되었다. 단백질 추출액과 DEAE-cellulose chormatography에서 분리된 Kuniz 및 Bowman-Birk T.I.의 polyacryamide gel 전기영동 pattern을 비교하여 본 결과, 확실하게 동정된 T.I.band는 band3과 band4로서 각각 Orf등이 발표한 Ti¹과 Ti2에 해당하였으며, 그 외에 band 6과 band 10이 T.I.로 추정되었고 band 1,2,5,7,8,9는 T.I.가 아닌 것으로 판명되었다. trypsin inhibitor 함유량은 총 trypsin units inhibited 값(T.U.I)으로 볼 때 42품종에서 25에서 76까지 품종 간에 차이가 현저하였으며 시비 및 파종기의 영향은 나타나지 않았다. Ti¹ inhibitor 를 보유하고 있는 것은 37품종이었고, Ti²를 보유하는 것은 7품종이었으며, Ti¹과 Ti²를 같이 가지고 있는 품종은 발견되지 않았다. 이러한 품종의 Ti¹,Ti² 보유 pattern은 재배조건에 의해 변화되지 않았다. 2조합의 pattern은 재배조건에 의해 변화되지 않았다. 2조합의 정역교배에서 얻은 F₁ 종자의 전기영동 pattern을 비교해 본 결과, Ti¹품종끼리의 교배종자에서는 정역교배에 상관없이 Ti¹ inhibitor 만 나타났고 Ti¹품종과 Ti²품종의 교배종자에서는 Ti²를 모본으로 한 종자에서는 Ti¹과 Ti² 두 inhibitor가 검출되었으나 여교배에서는 모본의 Ti¹ inhibitor만 검출되었다. 여교배에서 Ti¹만 나타난 것은 분석시료 종자가 적었고 교배의 여부를 확인할 수 없어 모본의 세포질적 영향에 의한 것인지 또는 자가수정에 의한 것인지 분명치 않았다. The protein extracts from soybean seeds were examined by polyacrylamide gel electrophoresis and the trypsin inhibitor (T.I) bands were detected. The water-extractable protein was fractionated into three fractions by Sephadex G-75 gel filtration. The T.I activity was found only in the second fraction. Kunitz and Bowman-Birk inhibitors were fractionated by DEAE-cellulose chromatography into seven and six fractions, respectively. In kunitz inhibitor, 5 fractions were found to have T.I activity and 4 fractions in Bowman-Birk inhibitor. From the and patterns of the protein extracts and those of DEAE-cellulose chromatographic fractions, it was found that band 3 and 4 were T.I. band, corresponding to Ti¹ and Ti² band, respectively. In addition, band 6 and 10 were presumed to be T.I. band. Of the 42 varieties sampled, 35 revealed only Ti¹ band and 7 only Ti² band. The T.I. band patterns were not changed by the culture condition. The T.I. content, when expressed as the number of trypsin units inhibited (T.U.I), showed remarkable differences from 25 to 76 between varieties. The seedtime and fertilization condition had no effect on the T.I. content. Judged from the results of F ₁seeds analysis, we assumed that Ti¹ and Ti²band were controlled by codominant allele at a single locus.

방사성 동위원소옥소(131I)에 의한 갑상선질환의 임상적 연구

이정상,이문호,고창순,노흥규,구인서,서환조,이경자,이홍규 대한핵의학회 1970 핵의학 분자영상 Vol.4 No.2

서울대학교 의과대학 내과학교실 및 방사성 동위원소 진료실에서 1960년 5월부터 1969년 10월까지 진료한 2,658명의 각종 갑상선 질환 환자에 대하여 131I에 의한 각종 갑상선 기능 검사 및 기능 항진증 환자에 대한 131I의 치료 성적을 종합 검토하여 아래와 같은 결론을 얻었다. 1) 2,658명의 갑상선 질환 환자중 독성 미만성 선종이 929명(34.9%)으로 가장 많고 비중독성 미만성 선종 및 비중독성 결절성 선종이 각각 762명(28.7%), 699명(26.3%)이며 기능저하가 210명(7.9%), 독성 결절성 선종이 58명(2.2%)였다. 2) 갑상선 질환의 성별 발생 빈도는 남자 300명(11.4%), 여자 2,358명(88.6%)로서 그 비는 1:8였다. 3) 연령별 발생 빈도는 20∼49세에서 전체의 79.1%인 2,102명이며 기능 항진증의 경우는 79.0%에 달하였다. 4) 각종 갑상선 기능 검사중 131I 섭취율, 131I 혈청내 방사능 BMR치등에 대한 고찰을 하는 한편 기능항진 및 저하증때 나타내는 각종 자학증세를 관찰하였다. 5) 갑상선 기능 항진증 환자 867명에 대하여 131I 치료를 하고 그 중 579명에서 47.8%의 초회 치료율을 확인하였다. 6) 131I 투여 후의 합병증인 기능 저하증의 발생 빈도는 초회 투여에서 6.75%였다. 7) 갑상선의 $quot; A summary of the clinical data of the (131)^I-thyroid function tests and the therapeutic results of 1(31I)^ among the 2,658 patients of various thyroid diseases treated over the past 10 years from May 1960 to Oct. 1969 at the Radioisotope Clinci and Laboratory, SNUH were presented and discussed. 1) The patients examined consisted of 929 cases (34.9%) of diffuse toxic goiter, 762 cases (28.7%) of diffuse nontoxic goiter, 699 cases (26.3%) of nodular nontoxic goiter, 58 cases (2.2%) of nodular toxic goiter and 210 cases (7.9%) of hypothyroidism. 2) There were 300 (11.4%) male and 2358 (88.6%) female, showing a ratio of 1:8. 3) The majority of patients (79.1%) were in the 3rd-5th decade of their lives. 4) The normal ranges, diagnostic values of (131)^I uptake test, 48 hrs serum activity, BMR and main subjective symptoms of various thyroid diseases were discussed. 5) In the 579 patients among 867 cases with hyperthyroidism treated with (131)^I, 47.8% were confirmed to be cured completely after single therapeutic doses. 6) The complications of 131I therapy were discussed and myxedema had developed in 6.75% of our patients. 7) The results of (131)^I thyroid function tests were analysed among the 160 cases of thyroid diseases which were confirmed the diagnosis with histopathological measures.

Diagnostic usefulness of a T cell-based assay for latent tuberculosis infection in kidney transplant candidates before transplantation

Kim, S.-H.,Lee, S.-O.,Park, I.-A.,Park, S.J.,Choi, S.-H.,Kim, Y.S.,Woo, J.H.,Park, S.-K.,Park, J.S.,Kim, S.C.,Han, D.J. Blackwell Publishing Inc 2010 Transplant infectious disease Vol.12 No.2

<P>S.-H. Kim, S.-O. Lee, I.-A. Park, S.J. Park, S.-H. Choi, Y.S. Kim, J.H. Woo, S.-K. Park, J.S. Park, S.C. Kim, D.J. Han. Diagnostic usefulness of a T cell-based assay for latent tuberculosis infection in kidney transplant candidates before transplantation.Transpl Infect Dis 2010: <B>12:</B> 113–119. All rights reserved</P><P>Background</P><P>The presence of latent tuberculosis (TB) infection (LTBI) should be evaluated before kidney transplantation. Although a new T cell-based assay for diagnosing LTBI gave promising results, this assay has not yet been compared with the tuberculin skin test (TST) for diagnosing LTBI in renal transplant candidates before transplantation.</P><P>Patients and methods</P><P>All adult patients admitted to a single institute for renal transplantation over a 1-year period were prospectively enrolled. A clinically predictive risk of LTBI was defined as: (i) recent close contact with a person with pulmonary TB; (ii) abnormal chest radiography; (iii) a history of untreated or inadequately treated TB; or (iv) a new infection (i.e., a recent conversion of TST).</P><P>Results</P><P>Of 209 renal recipients, 47 (22%) had a positive TST≥5 mm, 21 (10%) had a positive TST≥10 mm, 65 (30%) had a positive T-SPOT.<I>TB</I> test, and 25 (12%) had an indeterminate T-SPOT.<I>TB</I> test. The induration size of TST was significantly associated with a high positivity rate on T-SPOT.<I>TB</I> (<I>P</I><0.001). Agreement between T-SPOT.<I>TB</I> test and TST≥10 mm was fair (<I>k</I>=0.24, 95% confidence interval 0.11–0.36). However, neither univariate nor multivariate analysis showed any association between the clinical risk for LTBI and positivity on T-SPOT.<I>TB</I> or TST.</P><P>Conclusion</P><P>T-SPOT.<I>TB</I> test was more frequently positive than TST in renal transplant candidates. However, further longitudinal studies are awaited to determine whether the ability of T-SPOT.<I>TB</I> assay to detect LTBI in renal transplant recipients can better predict the development of TB than can TST after transplantation.</P>

어류 병원세균, Listonella anguillarum에 대한 Pseudomonas aeruginosa MB I-3의 항균 효과

이수정,윤이나,김진도,이정식,김은희,Lee, Su-Jung,Youn, I Na,Kim, Jin-Do,Lee, Jung Sick,Kim, Eunheui 한국어병학회 2014 한국어병학회지 Vol.27 No.1

질병 치료를 위하여 사용되는 항균제는 효과적이고 사용이 편리한 장점이 있지만, 내성균 발생이나 항균물질 잔류와 같은 문제점들을 안고 있다. 따라서 어류 질병 치료 및 예방을 위해 어류와 인체에 안전한 생약제 개발과 함께 어류 질병 원인균의 과다 발생을 억제하며 어체의 건강을 유지시키기 위하여 유용 균주를 이용하고자 하는 연구가 다양하게 진행되고 있다. 본 연구는 이전 연구에서 분리되어 Listonella anguillarum에 대하여 생장 억제효과가 있는 것으로 밝혀진 Pseudomonas aeruginosa MB I-3 (MB I-3)를 이용하여 넙치의 비브리오병에 대한 생물학적 방제효과를 검토하였다. Double layered plate assay와 co-culture을 통하여 MB I-3의 L. anguillarum에 대한 생장 억제능력을 조사하였고, MB I-3 균주 배양액을 ethyl acetate로 추출하여 disk 확산법으로 추출물의 항균 효과를 확인하였다. 액체 및 고체 배양에서 생장이 억제된 L. anguillarum을 전자현미경으로 관찰하였으며, 넙치 치어 사육 수조에 L. anguillarum과 MB I-3 균주를 동시에 첨가하여 폐사율을 비교하였다. MB I-3는 8종의 병원성 비브리오균에 대하여 항균력을 나타내었으며, 96시간 동안 실시한 co-culture에서 L. anguillarum은 배양 후 9시간까지 생장 증가를 보였으나, 그 후 감소하는 경향을 보였다. 한편 MB I-3 배양액 추출물 또한 L. anguillarum에 항균활성을 보여 항균 물질이 ethyl acetate로 추출됨을 알 수 있었다. 전자현미경 관찰에서 L. anguillarum은 세포질의 밀도 감소 및 세포막의 swelling에 의한 세포 용해 현상을 보였다. 한편 MB I-3를 L. anguillarum과 함께 투여한 넙치 치어는 대조군에 비해 누적 폐사율이 약 20% 감소되는 결과를 보였으므로, MB I-3를 이용한 수산용 probiotics 개발 가능성을 시사하였다. To study the possible use of probiotics in fish farming, The in vitro and in vivo antibacterial effects of Pseudomonas aeruginosa MB I-3 (MB I-3) against the fish pathogenic bacterium Listonella anguillarum were evaluated. The inhibitory effects of MB I-3 against vibrios were investigated by the double layer method and the co-culture. The results showed that MB I-3 inhibited the growth of pathogenic vibrios including Listonella anguillarum, Vibrio alginolyticus, Vibrio cholerae, Vibrio fluvialis, Vibrio furnissii, Vibrio harveyi, Vibrio parahaemolyticus and Vibrio vulnificus. Extracellular substances obtained from the cultural supernatant of MB I-3 by ethyl acetate extraction showed inhibitory effects on L. anguillarum. The antibacterial substance of MB I-3 was evaluated to destroy the cell membrane of L. anguillarum in electron micrographs. The probiotic effects of MB I-3 was tested by exposing olive flounder (Paralichthys olivaceus) fry to L. anguillarum with or without MB I-3. The cumulative mortality of olive flounder fry infected with L. anguillarum was 24% in the group with MB I-3, while it was 46% in the control group without MB I-3. These results indicate that MB I-3 has potential applications as a probiotic for the control of fish pathogenic vibrios in fish rearing system.

Manganese-superoxide dismutase (MnSOD), a role player in seahorse (<i>Hippocampus abdominalis</i>) antioxidant defense system and adaptive immune system

Perera, N.C.N.,Godahewa, G.I.,Lee, Seongdo,Kim, Myoung-Jin,Hwang, Jee Youn,Kwon, Mun Gyeong,Hwang, Seong Don,Lee, Jehee Elsevier 2017 Fish & shellfish immunology Vol.68 No.-

<P><B>Abstract</B></P> <P>Manganese superoxide dismutase (MnSOD) is a metaloenzyme that catalyzes dismutation of the hazardous superoxide radicals into less hazardous H<SUB>2</SUB>O<SUB>2</SUB> and H<SUB>2</SUB>O. Here, we identified a homolog of MnSOD from big belly seahorse (<I>Hippocampus abdominalis</I>; <I>HaMnSOD</I>) and characterized its structural and functional features. HaMnSOD transcript possessed an open reading frame (ORF) of 672 bp which codes for a peptide of 223 amino acids. Pairwise alignment showed that HaMnSOD shared highest identity with rock bream MnSOD. Results of the phylogenetic analysis of HaMnSOD revealed a close proximity with rock bream MnSOD which was consistent with the result of homology alignment. The intense expression of <I>HaMnSOD</I> was observed in the ovary, followed by the heart and the brain. Further, immune related responses of <I>HaMnSOD</I> towards pathogenic stimulation were observed through bacterial and viral challenges. Highest <I>HaMnSOD</I> expression in response to stimulants <I>Edwardsiella tarda</I>, <I>Streptococcus iniae</I>, lipopolysaccharide (LPS), and polyinosinic-polycytidylic acid (Poly I:C) was observed in the late stage in the blood tissue. Xanthine/xanthine oxidase assay (XOD assay) indicated the ROS-scavenging ability of purified recombinant HaMnSOD (rHaMnSOD). The optimum conditions for the SOD activity of rHaMnSOD were pH 9 and the 25 °C. Collectively, the results obtained through the expressional analysis profiles and the functional assays provide insights into potential immune related and antioxidant roles of <I>HaMnSOD</I> in the big belly seahorse.</P> <P><B>Highlights</B></P> <P> <UL> <LI> MnSOD was identified from big belly seahorse (HaMnSOD). </LI> <LI> HaMnSOD was cloned and expressed to evaluate its distinct functional features. </LI> <LI> XOD (Xanthine oxidase) assay confirmed the superoxide scavenging ability of HaMnSOD. </LI> <LI> Transcriptional level of <I>HaMnSOD</I> was modulated by pathological stress. </LI> </UL> </P>

신생아 집중치료를 받은 극소저출생체중아 치료성적의 시기에 따른 변화

김성신,김문희,심재원,고선영,이은경,장윤실,강이석,박원순,이문향,이상일,이흥재,Kim, Shung Shin,Kim, Moon Hee,Shin, Jae Won,Ko, Sun Young,Lee, Eun Kyung,Chang, Yun Sil,Kang, I Seok,Park, Won Soon,Lee, Mun Hyang,Lee, Sang Il,Lee, Heung J 대한소아청소년과학회 2002 Clinical and Experimental Pediatrics (CEP) Vol.45 No.7

목 적: 출생 체중 1,500 그램 미만의 극소저출생체중아(very low birth weight infant, VLBWI)의 치료성적은 신생아 집중치료술 향상여부를 모니터 하는 주요한 지표로 이용되고 있다. 이에 본 연구자들은 개원이래 최근 7년간 삼성서울병원 신생아 중환자실의 VLBWI 치료성적의 변화양상을 기간별로 관찰 분석하였다. 방 법: 1994년 10월부터 2000년 12월까지 삼성서울병원 신생아 중환자실로 생후 3일 이내 입원한 VLBWI 374명을 대상으로 기간을 나누어(I기 : 이미 성적이 보고된 1994. 10-1996. 9, II기 : 1996. 10-1998. 12, III기 : 1999. 1-2000. 12) 각 기별, 출생체중별, 재태기간별, VLBWI의 발생빈도와 생존율, 유병률 및 생존기간 등에 관해 의무기록지를 통한 후향적조사를 실시하였다. 생존율은(생존아/총출생 VLBWI)${\times}100$으 로 산출하였고 생존아는 신생아 중환자실에서 생존하여 퇴원한 경우로 정의하였다. 결 과 : VLBWI의 발생빈도는 기간별로 차이가 없었고(I기 : 1.3%, II기 : 1.5%, III기 : 1.4%), 생존율은 III기에 의미 있게 향상되었다. 출생체중별 생존율에서 III기에서 750 gm 미만군(vs II기)과, 1,250-1,499 gm 군(vs I기)의 향상이, 1,000-1,249 gm 군에서는 II기(vs I기)의 향상이 의미 있었고 최저출생 생존아는 I기 624 gm($26^{+5}$주), II기 667 gm($25^{+6}$주), III기 480 gm($26^{+2}$주)였다. 재태기간별 생존율에서 III기의 25-26주군과 29-30군이 I, II기에 비해 의미 있게 향상되었고 최저출생 재태기간의 생존례는 I기 26주(970 gm), II기 $23^{+5}$주(791 gm), III기 $24^{+1}$주(740 gm)였다. VLBWI의 주요 유병률 중 III도 이상의 심한 뇌실 내 출혈의 빈도가 III기 5%로 I기 13%, II기 10.5%에 비해 의미 있게 감소되었고, 전체 사망 중 7일 이전 사망률이 III기(15.4%)에 I기(55.5%)에 비해 의의 있게 감소되었다. 결 론 : 최근 VLBWI의 생존율이 주요 유병률의 증가 없이 현저히 향상되었고, 특히 26주 이하, 750 gm 미만의 초극소미숙아의 생존율 향상이 두드러졌다. Purpose : The outcomes of infants weighing less than 1,500 gm(very low birth weight infant : VLBWI) reflect recent progress in neonatal intensive care. In this study, we analyzed changes over time in survival rate and morbidity of VLBWIs during the past seven years. Methods : A retrospective review of medical records was analyzed for VLBWIs admitted to the neonatal intensive care unit of Samsung Medical Center within three days from birth. We compared the outcomes of previous corresponding data(period I : Oct. 1994 to Sept. 1996), with the outcomes of period II(Oct. 1996 to Dec. 1998) and period III(Jan. 1999 to Dec. 2000). Results : As shown in Tables 1 and 3, the distribution of birth weight, gestational age(GA), gender, and inborn admissions did not change during the 7-year study. The overall survival rate of VLBWI increased significantly over time(period I : 72% vs period III : 88.3%, P<0.05). Between period I and period II, the birth weight-specific survival rate increased by 23.6%(75% vs 92.7%, P<0.05) for infants 1,000 to 1,249 gm. Between period II and period III, the birth weight-specific survival rate increased three times(20% vs 66.7%, P<0.05) for infants <750 gm. The survivors of lowest birth weight included infants at 624 gm(GA : $26^{+5}$ weeks), 667 gm(GA : $25^{+6}$ weeks) and 480 gm(GA : $26^{+2}$ weeks) in each period. The gestational age-specific survival rate in period III increased significantly in GA 25-26 weeks and 29-30 weeks(vs period I & period II, P<0.05). The survivors of lowest gestational age included infants at GA 26 weeks(970 gm), GA $23^{+5}$ weeks(791 gm) and GA $24^{+1}$ weeks(740 gm) in each period. The incidence of severe IVH(grade III, IV) and the early death rate(< seven days) decreased in period III(vs period I; P<0.05), reflecting improvements in neonatal intensive care. Conclusion : The survival rate of VLBWI continues to increase, particularly for BW < 750 gm, GA < 26 weeks. This increase in survival is not associated by any increase in major morbidities.

Two NF-κB inhibitor-alpha (IκBα) genes from rock bream (Oplegnathus fasciatus): Molecular characterization, genomic organization and mRNA expression analysis after immune stimulation

Lee, Y.,Umasuthan, N.,Whang, I.,Revathy, K.S.,Lee, S.,De Zoysa, M.,Oh, C.,Kang, D.H.,Noh, J.K.,Lee, J. Academic Press 2014 FISH AND SHELLFISH IMMUNOLOGY Vol.41 No.2

IκBα is a member of IκB family, which sequesters NF-κB in an inactivate form in the cytoplasm and blocks the translocation of NF-κB to nucleus. The IκBα paralogs of rock bream (OfIκBα-A and OfIκBα-B) encoded IκBα proteins with typical features including, highly conserved IκB degradation motif, six ankyrin repeats and a PEST sequence. However, their amino acid identity and similarity were only 55.6 and 69.7%, respectively suggesting that these two genes could be the two different isoforms of IκBα. The number and size of the exons of OfIκBα-A and OfIκBα-B were conserved well with all the compared vertebrate species, although they have significantly different genomic sizes. Phylogenetic analysis revealed that OfIκBα-A and OfIκBα-B proteins cluster with IκBα family members; however, they were grouped with different subclades in IκBα family. Tissue specific expression of OfIκBα mRNA was constitutively detected in all the tested tissues, and they showed the higher transcription level in heart, liver, gill and peripheral blood cells, respectively. The injection of flagellin stimulated the mRNA expression of OfIκBα paralogs in head kidney and intestine. Moreover, the OfIκBα mRNA expression in gill and liver was significantly up-regulated by LPS, poly I:C and Edwardsiella tarda challenges. The transcription of OfIκBα was up-regulated in early-phase of injection and then rapidly restored. These results suggest that the OfIκBα paralogs might be involved in rapid immune responsive reactions in rock bream against bacterial and viral pathogens.

Effects of dextrorotatory morphinans on brain Na⁺ channels expressed in Xenopus oocytes

Lee, J.H.,Shin, E.J.,Jeong, S.M.,Lee, B.H.,Yoon, I.S.,Lee, J.H.,Choi, S.H.,Kim, Y.H.,Pyo, M.K.,Lee, S.M.,Chae, J.S.,Rhim, H.,Oh, J.W.,Kim, H.C.,Nah, S.Y. North-Holland ; Elsevier Science Ltd 2007 european journal of pharmacology Vol.564 No.1

We previously demonstrated that dextromethorphan (DM; 3-methoxy-17-methylmorphinan) analogs have neuroprotective effects. Here, we investigated the effects of DM, three of its analogs (DF, 3-methyl-17-methylmorphinan; AM, 3-allyloxy-17-methoxymorphian; and CM, 3-cyclopropyl-17-methoxymorphinan) and one of its metabolites (HM; 3-methoxymorphinan), on Na<SUP>+</SUP> channel activity. We used the two-microelectrode voltage-clamp technique to test the effects of DM, DF, AM, CM and HM on Na<SUP>+</SUP> currents (I<SUB>Na</SUB>) in Xenopus oocytes expressing cRNAs encoding rat brain Nav1.2 α and β1 or β2 subunits. In oocytes expressing Na<SUP>+</SUP> channels, DM, DF, AM and CM, but not HM, induced tonic and use-dependent inhibitions of peak I<SUB>Na</SUB> following low- and high-frequency stimulations. The order of potency for the inhibition of peak I<SUB>Na</SUB> was AM-CM > DM=DF. The DM, DF, AM and CM-induced tonic inhibitions of peak I<SUB>Na</SUB> were voltage-dependent, dose-dependent and reversible. The IC<SUB>50</SUB> values for DM, DF, AM and CM were 116.7+/-14.9, 175.8+/-16.9, 38.6+/-15.5, and 42.5+/-8.5 μM, respectively. DM and its analogs did not affect the steady-state activation and inactivation voltages. AM and CM, but not DM and DF, inhibited the plateau I<SUB>Na</SUB> more effectively than the peak I<SUB>Na</SUB> in oocytes expressing inactivation-deficient I1485Q-F1486Q-M1487Q (IFMQ3) mutant channels; the IC<SUB>50</SUB> values for AM and CM in this system were 8.4+/-1.3 and 8.7+/-1.3 μM, respectively, for the plateau I<SUB>Na</SUB> and 43.7+/-5.9 and 32.6+/-7.8 μM, respectively, for the peak I<SUB>Na</SUB>. These results collectively indicate that DM and its analogs could be novel Na<SUP>+</SUP> channel blockers acting on the resting and open states of brain Na<SUP>+</SUP> channels.

Effect of intermittent pressure-assisted forward osmosis (I-PAFO) on organic fouling

Lee, J.,Kook, S.,Lee, C.,Kim, I.S. Elsevier 2017 Desalination Vol.419 No.-

This study investigated the feasibility of intermittent pressure-assisted forward osmosis (I-PAFO) operation for organic fouling mitigation, using sodium alginate as the model foulant. FO and PAFO were also operated to compare system performances in terms of water flux behavior, flux recovery by physical cleaning, fouling propensity, energy consumption, and membrane area required. Results showed that I-PAFO obtained higher water flux and flux recovery by physical cleaning than PAFO because of its lower fouling tendency. I-PAFO was able to reduce not only the accumulated foulant mass on the membrane surface, but also fouling layer compaction through the intermittent pressurization. Furthermore, it displayed benefits in terms of reducing membrane area required and operating energy compared to PAFO, due to its higher water productivity and sustainability. Therefore, I-PAFO can be a plausible option for saving membrane costs and operating energy when FO operations are concerned particularly in accordance with hybridization with RO (i.e. I-PAFO-RO hybrid process).

Power-efficient and high-performance block I/O framework for mobile virtualization systems

Lee, K.,Lee, D.,Lee, S.,Eom, Y. I. Kluwer Academic Publishers 2017 The Journal of supercomputing Vol.73 No.4

<P>A virtualized system generally suffers from low I/O performance, mainly caused by its inherent abstraction overhead and frequent CPU transitions between the guest and hypervisor modes. The recent research of polling-based I/O virtualization partly solved the problem, but excessive polling trades intensive CPU usage for higher performance. This article presents a power-efficient and high-performance block I/O framework for a virtual machine, which allows us to use it even with a limited number of CPU cores in mobile or embedded systems. Our framework monitors system status, and dynamically switches the I/O process mode between the exit and polling modes, depending on the amounts of current I/O requests and CPU utilization. It also dynamically controls the polling interval to reduce redundant polling. The highly dynamic nature of our framework leads to improvements in I/O performance with lower CPU usage as well. Our experiments showed that our framework outperformed the existing exit-based mechanisms by 10.8 % higher I/O throughput, maintaining similar CPU usage by only 3.1 % increment. In comparison to the systems solely based on the polling mechanism, ours reduced the CPU usage roughly down to 10.0 % with no or negligible performance loss.</P>