대학 교양으로서 일반생물학 수업에서 ‘기후 변화’ 교육

박돈하(Don Ha Park),장수철(Soo Chul Chang) 목원대학교 교양교육혁신연구센터 2024 지식과 교양 Vol.- No.14

기후변화는 인류 모두가 풀어야 할 급하고도 중요한 과제이다. 그래서 대학 교육, 특히 교양교육에서 기후변화 교육을 수행해야 함은 이론의 여지 없이 너무도 당연하다. 본 연구는 생물학에서 가능한 ‘기후변화’ 교육을 모색하였다. 이를 위해 교양교육 과정의 일반생물학 교과 내용을 분석하였고 수도권과 지방의 국공립과 사립 대학이 개설한 교양생물학 교과 주제를 조사, 분석하였다. 분석 결과, 지구 기후 이해를 위한 원리와 개념을 제공하는 생태학 교육은 매우 중요하므로 교양 교과로서 일반생물학 수업은 원칙적으로 반드시 교과 과정에 생태학 단원을 포함하여야 한다는 결론에 이르렀다. 그런데 대학들의 교과 주제를 분석한 결과, 대부분 대학은 일반생물학 교과목에 이 단원을 포함하지 않았다. 이에 대한 대책으로, 생태학 단원 전체를 한 학기 또는 두 학기 교과 과정에 포함하지 못하더라도 기후변화에 관련된 5~6 주제를 다른 단원에 연결하여 수업을 진행할 수 있을 것이다. 또는 몇몇 대학처럼 생태학 교과목을 따로 개설할 필요가 있다. 또는 기후변화를 포함하는 다른 과학 교과목을 개설할 수도 있다. 다만, 이 경우 학생들의 교과목 수강 지도가 필요한데, 수강 지도를 담당하는 교원을 위한 기후변화 교육이 필요한 점은 과제로 남게 된다. 더불어 생물학뿐만이 아닌 자연과학과 인문사회과학을 포함한 여러 교양교육 교과들이 이러한 시도를 함으로써 기후변화라는 과제를 푸는 데에 도움을 제공하여야 한다. 더불어 교양기초교육원에서 제정한 ‘교양기초교육의 목적’에 기후변화에 관한 내용을 추가할 것을 제안한다. Climate change is an urgent and important problem that all humanity must solve. Therefore, it is indisputable that climate change education should be provided in universities, especially as part of liberal education. This study explored possible climate change education in biology. For this purpose, we analyzed the contents of the general biology curriculum in the general education curriculum and investigated and analyzed the topics of the general biology curriculum offered by public and private universities in the metropolitan area and local regions. As a result we came to the conclusion that general biology classes as a liberal arts subject must, in principle, include an ecology unit in the curriculum. However, most universities in Korea do not include this unit in their general biology curriculum. As a countermeasure, even if the entire ecology unit cannot be included in the curriculum for one or two semesters, the class can connect five to six topics related to climate change to other units. Otherwise, like some universities, there is a need to open a separate ecology course. Alternatively, other science courses that include climate change could be offered. In this case, though, guidance is needed for students to take the courses, and the need for climate change education for teachers in charge of course guidance remains an issue. In addition, various other liberal arts education subjects, including not only biology but also natural sciences, humanities, and social sciences, should also make such attempts to help solve the problem of climate change. Moreover, we propose adding content on climate change to the ‘Purpose of Liberal Education’ statement established by the Korea National Institute for General Education.

심근 수축빈도수 변형에 따른 심근 세포내 Ca^(+)섭취의 변동에 대한 연구 : and Experimental study on die

고창만,하윤 연세대학교 원주의과대학 1993 원주의대논문집 Vol.6 No.1

Prednisolone 投與로 因한 家兎中樞淋巴組織의 形態學的硏究

河在昌,李東久,洪錫宰 啓明大學校 醫科大學 1982 계명의대학술지 Vol.1 No.1

成熟家兎를 實驗動物로 하여 prednisolone 을 5㎎ 및 10㎎ 씩 1日 1回 連 3日間 注射하고 中樞淋巴組織인 胸腺과 蟲垂淋巴組織에 惹起되는 變化를 機能的組織構造에 따라 光學 및 電子顯微鏡的으로 檢索한 結果를 要約하면 다음과 같다. 組織學的으로 胸腺에 있어서는 小葉皮質에서 淋巴球의 甚한 消失과 細綱細胞 및 大食細胞의 顯著한 增加를 볼 수 있었으나 隨質에서는 淋巴球가 거의 減少되지 않았다. 蟲垂淋巴組織은 dome, corooa 및 follicle에서 다같이 大小淋巴球의 甚한 消失과 大食細胞의 著明한 增加를 볼 수 있었으며 TDA에서는 淋巴球가 極히 輕한 程度로 減少하였을 뿐으로서 거의 正常한 狀態로 보였다. 電子顯微鏡的으로 胸腺皮質의 淋巴球는 核邊綠의 不規則, 核膜의 消失 및 核破壞 等의 甚한 變性 내지 壞死性變化가 惹起되었으며 細綱細胞 및 大食細胞에서는 空胞의 養性擴張, mitochondria의 종신 및 cristae의 消失 그리고 破壞된 淋巴球의 탐식 等이 5㎎ 注射群보다는 10㎎ 群에서 좀 더 顯著하게 나타났다. 그러나 隨質에서는 몇몇 淋巴球에서 核濃縮과 核邊綠의 不規則性이 있을뿐 著明한 變性變化는 없었다. 蟲垂淋巴組織에서도 dome, corona 및 follicle의 淋巴球는 甚한 壞死性變化를 보였으며 TDA에서는 그 變化가 極히 輕하였다. Dome 및 follicle의 大食細胞에서는 破壞된 淋巴球가 가끔 탐식되어 있었다. 以上의 成績으로 보아 一般的으로 cortiosteroid의 中樞淋巴組織에 對한 影響은 胸腺에서는 皮質의 淋巴球에 그리고 蟲垂淋巴組織에서는 주로 B淋巴球領域의 淋巴球에 일어나며 그 變化는 非可逆性 壞死까지도 誘發하는 것으로 推定된다. This study was carried out to investigate morphological changes in the central lymphoid tissue of thymus gland and appendix of 12 healthy adult rabbits treated with injecting prednisolone of 5 and 10mg each to the animals once per day 3 consecutive days. The results were as follows: Light microscopically, a considerable loss of lymphocytes in lobular cortex of thymus gland, along with noticeable increase of macrophages and reticulum cells, were found. However, no significant decrease of lymphocytes in its medulla persent. Significant loss of large and small lymphocytes and considerable increased macrophages in the areas of dome, corona, and follicles of appendiceal lymphoid tissue were noted. However, very meagre decrease of lymphocytes in thymus dependent area only was noticed. Electron microscopically marked degeneration and necrotic changes of lymphocytes, such as irregularity of nulear margin, loss of nuclear membrane, and destruction of lymphocytes in the cortex of thymus gland occured. in reticulum cells and macrophages, cystic degeneration of vesicles, swelling of mitochondria, loss of cristae, and phagocytosis of destructed lymphocytes were prominent in the group of 10mg injection than in that of 5mg. Nevertheless, nuclear condensations and irregularities of nuclear margin of some lymphocytes were noticed in medulla with no clear degenerative changes. In appendiceal lymphoid tissue, a severe nocrotic changes of lymphocytes of dome, corona and follicles were observed. However, its changes in thymus dependent area were very little. In macrophages of dome and follicles, destructed lymphocytes were seen to be occasionally phagocytosed. It may be summarized that the effects of corticosteroid on the central lymphoid tissue take place in lymphocytes in cortex of thymus gland and in lymphocytes of B lymphocytical area of appendiceal lymphoid tissue. It may also be assumed that the changes aforementioned can include irreversible necrosis.

수피 돈분 부산물 비료의 부숙단계별 분광학적 특성 변화

박창진,김정규,김정제,박용하,신명교,양재의,최문헌 한국환경농학회 1999 한국환경농학회지 Vol.18 No.4

본 연구는 수피 부산물 비료의 돈분 부산물 비료의 부숙단계별 시료의 유기물 분획의 함량 변화, Δlog K값과 RF값 등의 분광학적 특성 변화, 원형여지 chromatograp의 변화를 측정하여, 부숙도의 판정 기준 설정을 위한 기초 자료로 활용하는데 그 목적이 있다. 그 결과를 요약하면 다음과 같다. 수피와 돈분 부산물빌 중 HA-C와 FA-C의 함량은 대체로 부숙이 진행됨에 따라 감소하는 경향이었고, HA-C/FA-C 비는 증가하였다. 수피와 돈분 부산물 비료의 Δlog K값은 부숙이 진행됨에 따라 감소하였으며, RF값은 증가하였다. 생수피의 부식산 형태는 R_p 형태였으나, B형태를 거쳐 120일경과 후 A형태로 변화하여 거의 완숙상태에 도달하였으며, 돈분 부산물 비료의 경우 40일경과 후에도 B형태로 나타나 유기물질의 부숙이 진행중인 것으로 판단되었다. 수피부산물 비료의 원형여지 chromatograph는 120일경과 후에 규칙적인 톱니 모양을 하고 있어 완숙단계에 이른 것으로 판단할 수 있었으나, 돈분 부산물의 경우는 40일이 경과한 후에도 부분적으로 불규칙적인 모양을 하고 있어 부숙이 진행되고 있는 상태인 것으로 판단할 수 있었다. Changes of the spectroscopic characteristics of the organic matter fractions and circular filter paper chromatograph were assessed for the bark and piggery manure composts during the composting. as an approach to base the criteria of the compost maturity evaluation. Contents of humic acid-C (HA-C) and fulvic acid-C (FA-C) in both bark and piggery manure composts were decreased as the composting got closer to maturity, but the ratios of HA-C/FA-C were increased. During the composting. Δlog K values were decreased, but RF values were increased. Humic acid of the mature bark compost after 120 days of composting was A-type, as compared to Rp-type for the raw bark and B-type for the immature compost. However. humic acid of the mature piggery manure composts after 40 days of composting was B-type, indicating the humification of the organic matter fractions continued at this stage. Circular filter paper chromatograph of the mature bark compost exhibited the regular sawteeth pattern at the edge, but that of the mature piggery manure showed an irregular sawteeth pattern. Results demonstrated that spectroscopic characteristics and circular filter paper chromatograph of the organic by-product composts might be employed for the compost stability assessment.

인터넷과 시민운동의 변화

하승창(Seung-Chang Ha) 한국비영리학회 2002 한국비영리연구 Vol.1 No.2

인터넷은 이미 과거 전화가 다가 온 것처럼 아니 그 이상으로 우리 생활의 일부가 되고 있다 인터넷이 일반화된 것은 그리 오래 되지 않으나, 시민운동 진영에게 인터넷이 익숙해진 것은 2000년 총선시민연대 활동을 거치면서 부터이다 1999년의 안티닉스사이트의 경우나 함께하는 시민행동의 경우, 혹은 그 이전의 진보넷처럼 일부 앞선 경험이 있기는 하나 본격적인 흐름이 형성된 것은 2000년부터라 할 것이다 이를 전후로 하여인터넷은 시민운동에게도 변화를 가져오기 시작하였다 시민운동에 있어서 인터넷은 우선 운동방식의 변화를 가져 왔다 새로운 시위양식도 생겨났고, 항의의 방식도 전자적 방식이 사용되었다 홍보에 있어서도 홈페이지의 위력은 과거의 잡지에 비해 훨씬 신속하고 광범한 것이었다 인터넷은 시민운동단체들의 운영방식에도 변화를 가져올 것을 예고하고 있는 데 이미 이메일을 사용한 연락과 회의는 점차 보편화되기 시작하고 있고, 함께 하는 시민행동처럼 온라인으로 총회를 치르는 단체도 나타나기 시작하였다 그러나 여전히 시민단체들 대다수는 인터넷이 주로 검색과 자신의 단체를 홍보하는 수준에 머물러 있으며 인터넷 사용을 일상화하기 위해 필요한 재정이나 훈련된 인력의 부족을 호소하고 있다 이들은 향후 시민단체 상호간의 격차가 정보화를 거치면서 더욱 커질 것으로 예측하고 있다 따라서 시민단체의 균형적 발전을 위해서는 시민단체 상호간의 정보격차를 줄이는 것도 중요한 일이 될 것이다 Internet cannot be separated from our daily life like telephone couldn't in the past. The influence of Internet, if anything, is bigger than that of telephone. It is not a long time since wide use of internet NGOs have been accustomed to internet since 2000 Citizen Solidarity for General Election. Strictly speaking, there was some case in which internet was used as a means of movement by NGOs or was the field of issue of them The cases of web site against Anti-Nics in 1999 and of Citizen's Action Network are examples of the cases The case of Jinbonet, which is prior to those case, is same But it may be said that the year 2000 was the time the use of internet by NGOs has begun in earnest. Since that time, internet has changed the act of NGOs. Above all, internet changed the process of NGO's activities. New method of demonstration appeared, and electronic method of protest was used by them. The effect of Web Page is superior to paper megazine in the point of the promptitude and extension of PR And it is expected that Internet will make the management of NGOs changed. E-mail meeting and communication is already widely used. Moreover, such NGOs as Citizen's Action Network have held a general meeting. But, most NGOs cannot go beyond using internet as a means of searching and PR, yet And they lack funds and human resource which they need in order to expand the range of usingS internet They expect that information and communication technology will reinforce the existing gap among NGOs Therefore, the valanced development among NGOs require to bridge the digital divide among them

Bloodstream Infections and Clinical Significance of Healthcare-associated Bacteremia: A Multicenter Surveillance Study in Korean Hospitals

Son, Jun Seong,Song, Jae-Hoon,Ko, Kwan Soo,Yeom, Joon Sup,Ki, Hyun Kyun,Kim, Shin-Woo,Chang, Hyun-Ha,Ryu, Seong Yeol,Kim, Yeon-Sook,Jung, Sook-In,Shin, Sang Yop,Oh, Hee Bok,Lee, Yeong Seon,Chung, Doo The Korean Academy of Medical Sciences 2010 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.25 No.7

<P>Recent changes in healthcare systems have changed the epidemiologic paradigms in many infectious fields including bloodstream infection (BSI). We compared clinical characteristics of community-acquired (CA), hospital-acquired (HA), and healthcare-associated (HCA) BSI. We performed a prospective nationwide multicenter surveillance study from 9 university hospitals in Korea. Total 1,605 blood isolates were collected from 2006 to 2007, and 1,144 isolates were considered true pathogens. HA-BSI accounted for 48.8%, CA-BSI for 33.2%, and HCA-BSI for 18.0%. HA-BSI and HCA-BSI were more likely to have severe comorbidities. <I>Escherichia coli</I> was the most common isolate in CA-BSI (47.1%) and HCA-BSI (27.2%). In contrast, <I>Staphylococcus aureus</I> (15.2%), coagulase-negative <I>Staphylococcus</I> (15.1%) were the common isolates in HA-BSI. The rate of appropriate empiric antimicrobial therapy was the highest in CA-BSI (89.0%) followed by HCA-BSI (76.4%), and HA-BSI (75.0%). The 30-day mortality rate was the highest in HA-BSI (23.0%) followed by HCA-BSI (18.4%), and CA-BSI (10.2%). High Pitt score and inappropriate empirical antibiotic therapy were the independent risk factors for mortality by multivariate analysis. In conclusion, the present data suggest that clinical features, outcome, and microbiologic features of causative pathogens vary by origin of BSI. Especially, HCA-BSI shows unique clinical characteristics, which should be considered a distinct category for more appropriate antibiotic treatment.</P>

Audiologic Results of Ossiculoplasty Using Malleus Footplate Assembly: The Comparison between Autologous Incus and Hydroxyapatite

Sun O Chang,Sue Jean Mun,Joo Hyun Park,Chang Myeon Song,Kyu-Hee Han,이준호,Seung Ha Oh 대한청각학회 2011 Journal of Audiology & Otology Vol.15 No.3

Introduction A disruption of the ossicular chain of the middle ear causes conductive hearing loss. Ossicular reconstruction is performed to restore hearings in those patients with congenital ossicular chain anomaly or ossicular chain disruption caused by chronic otitis media or cholesteatoma. A study from Japan with 52 auditory ossicular malformation revealed that 44% of the patients had a fixation of the stapes, 40% had incudostapedial joint defects followed by fixation of the malleus and/or incus and defects in the incudostapedial joint with a fixation of the stapes.1) One of the most common ossicular chain anomalies in Korea was a stapes footplate fixation (54.5%) followed by a mobile stapes footplate with other anomalies (19.7%) including a stapes without suprastructure and an incus long process, stapes without anterior crus and an incus long process.2) One of the most common ossicular chain anomalies is the absence of an incus with or without an intact stapes suprastructure. In incudostapedial deformed ears, ossiculoplasty is mandatory to restore the hearing process. Ossiculoplasty is also needed in cases with incus long process erosion with inflammation. As the most vulnerable ossicles, one report said that incus erosion is found in 80% of the chronic otitis media.3) Austin-Kartush classified ossicular chain disruptions into four categories after 1,151 operation on chronic otitis media. Group A ears with an intact malleus handle and a stapes suprastructure was found in 59.2% followed by group B ears with an intact malleus handle but an eroded stapes suprastructure group.4) In the group of a tympanic membrane and malleus preserved but a stapes suprastructure eroded, ossicular continuity can be restored between the stapes footplate and manubrium of the malleus with the method of malleus footplate assembly (MFA) using either the incus body or if the incus is unavailable, a biocompatible material such as hydroxyapatite (HA).5,6,7) Until now, MFA has proven to be the safe and effective way to restore hearings in such patients.8,9,10,11,12)Though successful results using MFA with either incus body or biocompatible material are reported world widely, there were a few reports on audiologic results after MFA ossiculoplasty in Korea. Authors reviewed our procedure and report hearing results of ossiculoplasty with MFA using either incus or HA. In this paper, a single-surgeon series of 32 MFA operations was analyzed. The cases were limited to autologous interposition grafts performed on Austin-Kartush group B ears in order to provide consistency within the analysis. Subjects and Methods Data collection A retrospective evaluation has been carried out on patients who underwent MFA ossiculoplasty between September 2001 and March 2010 in Seoul National University Hospital. A total of 55 patients with Austin-Kartush type B defect repaired with incus body or HA were identified. Of those, 20 were excluded due to a failure to recover operation records or a lack of no more than 1 year postoperative audiograms. Three patients who had undergone MFA with a homologous incus were excluded in order to provide consistency within the analysis. Finally, 32 cases were enrolled into the study. All procedures were conducted by a single surgeon. All data including previous operations, follow-up duration, age, sex, etiology, materials which were used in the operation, combined mastoidectomy, complications, and revision operations were analyzed. Eustachian tube function was analyzed according to the results of the Eustachian tube test. The status of the middle ear mucosa was described as either 'healthy' or 'inflamed' according to the operation records. Demographic data are presented in Table 1. Analysis of audiologic data Preoperative and postoperative hearing results were evaluated according to the guidelines of the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology-Head Neck Surgery Foundation13) an... Background and Objectives: Absence of incus is one of the most common ossicular anomalies and also frequently found in chronic otitis media or chornic otitis media with cholesteatoma. Ossiculoplasty with malleus footplate assembly (MFA) can be an excellent option in the above situations. We reviewed our procedures and evaluated the hearing results of ossiculoplasty using the MFA. Subjects and Methods: This study retrospectively reviews a series of 32 patients who underwent MFA ossiculoplasty between September 2001 and March 2010 in an academic tertiary referral center. The autologous incus or hydroxyapatite (HA) was used as materials for reconstruction. Results: Thirteen of 32 patients (40.6%) had ossicular chain anomaly, 9 patients (28.1%) had congenital cholesteatoma and 8 patients (25.0%) had chronic otitis media with cholesteatoma and 2 patients (6.3%) had chronic otitis media. The patients with ossicular chain anomaly showed the greatest air-bone gap (ABG) closure. Overall, postoperative ABG was 17.7±11.7 dB at postoperative 6 months and 19.7±14.3 dB at postoperative 1 year, compared with preoperative ABG of 37.9±9.3 dB. There was no statistical difference of ABG at postoperative 12 months, 24 months between MFA using incus (n=17) and HA (n=15)(p=0.300, and p=0.563). There was no meaningful difference of postoperative ABG between the patients with combined mastoidectomy (n=10) and those without mastoidecmoy (n=22)(p=0.555). No extrusions occurred.

자연재난과 젠더 : 개도국 양성평등 제고 가능성과 한국의 성인지적 재난관리정책을 위한 시사점

장은하(Eun-Ha Chang) 한국여성정책연구원 2015 여성연구 Vol.88 No.-

Since 1990s, the magnitude and frequency of mega disasters around the globe are on the rapid rise. The destructive impact of natural disasters is vast. They not only destroy personal life, health and wellbeing but also devastates livelihoods, social services and environments. Disasters are also gender discriminatory. Due to their biological/physiological characteristics and unequal status in social, economic and political life, women's vulnerability increases when disaster occurs. Despite such destructiveness however, disasters sometimes act as an opportunity for change towards a more gender-equal society. The demise of existing infrastructure and influx of external resources may create a positive opportunity for a change. Against this backdrop, this study examines whether fundamental changes toward gender equality can take place during the reconstruction phase of a disaster in developing countries, and also examines implications for the disaster management policy of South Korea. The author examines several cases studies, using Caroline Moser's gender planning theory, focusing on practical gender needs and strategic gender needs. The case studies reveal that post-disaster reconstruction programs work towards satisfying both practical and strategic gender needs, and the effect is greater when the assistance organization has high gender sensitiveness. Nonetheless, taking a strategic gender approach did not directly resulted in more fundamental or structural change. In some cases negative results were observed. In addition, the existence of women's organization, men's resistance, trauma therapy were identified as importance factors to be considered for an effective change. This study concludes by suggesting several implications for South Korea’s gender-conscious disaster management policy. 1995년 일본 한신 대지진, 2004년 인도양 쓰나미, 2010년 아이티 대지진, 20011년 일본 쓰나미 등 1990년도 이후 전 세계적으로 대형 자연재난의 빈도와 강도가 급속하게 증가하고 있다. 재난은 사망, 부상, 질병 등의 물리적 인명 피해 뿐 아니라, 생계기반을 파괴하고, 사회 서비스를 마비시키며, 사회경제적 혼란, 환경파괴를 불러오는 등 개인과 사회의 전 영역에 심각한 영향을 끼친다. 이러한 재난의 영향력은 또한 성차별적이다. 여성들은 생물학적/생리학적 특성과 한 사회 내에서 차지하는 사회, 경제, 정치적으로 불평등한 위치와 차별로 인해 재난 발생 시 취약성이 증가한다. 그러나 이러한 파괴력에도 불구하고 재난은 양성평등적 변화를 촉진하기도 한다. 재난으로 인한 기존 질서의 붕괴와 복구 과정에서의 자원의 유입은 해당 사회의 여성의 지위 향상과 양성평등을 위한 긍정적인 변화의 기회로 작용할 수 있기 때문이다. 이러한 논의를 배경으로 본 연구는 자연재난 복구 과정을 통해서 양성평등을 위한 근본적이고도 구조적인 변화가 일어날 수 있는지를 개도국의 사례에 비추어 고찰하고 한국에의 시사점을 도출하는 것을 그 목적으로 한다. 양성평등적 변화를 위해서는 모저(Moser)의 실제적 젠더 요구(practical gender needs, PGN)와 전략적 젠더 요구(strategic gender needs, SGN) 모두 충족되어야 하나, 보다 구조적인 변화를 위해서는 전략적 젠더 요구가 충족되어야 할 것으로 보았다. 연구 결과로는 검토한 대부분 사례에서 여성의 실제적 젠더 요구와 전략적 젠더 요구에 부응하는 지원이 이루어 진 것으로 관찰되었으며 특히 지원 단체의 젠더 민감도가 높은 경우 전략적 젠더 요구가 효과적으로 충족되는 것으로 나타나났다. 그러나 전략적 젠더 요구 충족을 위한 접근이 시도되었다고 해서 이것이 바로 구조적이고도 근본적인 변화로 이어지는 것은 아니라는 것을 확인 할 수 있었으며, 오히려 부정적인 변화가 일어난 경우도 있었다. 또한 보다 구조적인 양성평등적 변화를 달성하기 위해서는 재난 복구 시기에서의 여성조직의 역할, 남성의 저항에 대한 대응, 트라우마 치료 등의 중요성을 확인하였다. 아울러 양성평등 제고를 위한 내재적, 외재적 요인들을 분석함으로써 향후 한국의 성인지적 재난관리정책을 위한 시사점을 도출하였다.

Enhancement of bio-stability and mechanical properties of hyaluronic acid hydrogels by tannic acid treatment

Lee, Ho-Yong,Hwang, Chang-Ha,Kim, Hyoun-Ee,Jeong, Seol-Ha Elsevier 2018 Carbohydrate Polymers Vol.186 No.-

<P><B>Abstract</B></P> <P>Hyaluronic acid (HA) has been widely investigated because of its excellent biocompatibility and its ability to form hydrogels with various chemical modifications. However, HA hydrogels undergo rapid degradation and exhibit poor mechanical stability under physiological conditions. Tannic acid (TA), a naturally occurring polyphenol found in plants and fruits, has recently attracted interest as a crosslinking agent because of its abundant hydroxyl groups. In this study, we prepared HA hydrogels chemically crosslinked by polyethylene glycol diglycidyl ether (PEGDE) and treated with TA in an attempt to enhance the physical properties of HA hydrogels. TA acts as a physical crosslinker owing to the strong hydrogen bonding between TA and PEGDE, resulting in improved mechanical properties that support both cell attachment and proliferation without any sign of cytotoxicity. The enzymatic stability of the HA–TA hydrogels was significantly enhanced with the addition of TA, which was attributed to the hyaluronidase inhibition activity of TA. Additionally, the antioxidant potential of TA resulted in good resistance to degradation by reactive oxygen species, which can be generated in human tissues.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Crosslinking strategy of hyaluronic acid by using polyethylene glycol and tannic acid is proposed. </LI> <LI> Superior bio-stability and mechanical properties of hyaluronic acid hydrogels are obtained. </LI> <LI> Enhanced biological responses of hyaluronic acid- tannic acid hydrogel are achieved. </LI> </UL> </P>

척수손상후 운동 유발전위와 지각 유발전위의 비교

지철,이재수,하영수,최창락,송진언 대한신경외과학회 1987 Journal of Korean neurosurgical society Vol.16 No.4

Electrical monitoring of the nervous system offers the potential for the detection of injury, intraoperatively. The relationship of MEP(Motor Evoked Potential) and SEP(Sensory Evoked Potential) taken in 30 rats before and after spinal cord injury is reported. MEP was obtained from distal portion to the site of spinal cord injury by electrical stimulation of the cerebral motor cortex after insertion of a ball electrode in the cerebral motor cortex. SEP was collected at the cerebral somatosensory cortex during the sciatic nerve stimulation. Experimental animals were divided into a 20g㎝ spinal cord-trauma group and 50g㎝ spinal cord-trauma group. Changes of cardiopulmonary function after cerebral motor cortex stimulation and pre-and post-injury MEP and SEP were obtained at constant time interval. The results were follows : 1) Significant changes in blood pressure, pulse rate, and respiratory rate were noted to be elevated after stimulation of cerebral motor cortex and these were returned to normal in 10 minutes after stimulation. 2) MEP in control group showed that the latency was 8.6±1.54msec and the amplitude was 20.60±3.2㎶. In MEP of 20g㎝ spinal cord trauma group, the latency was increased to 30% (11.26±1.76msec) compared to control group at 10 minutes after the injury and the amplitude was decreased to 29% (14.60±2.99㎶). The latency was slowly decreased with the passage of time, to 21% increase. (10.42±1.84msec) at 1 hour after injury but the amplitude was not changed. In 50 g㎝ spinal cord-trauma group the latency was decreased to 75%(4.9±1.52㎶) compared to control group. With the passage of time, no change was revealed in latency but amplitude was decreased. The amplitude was decreased to 80%(4.00±1.49㎶) compared to control group. Change of MEP was marked in 50g㎝ spinal cord-trauma group. With the passage of time MEP was slightly improved in 20g㎝ spinal cord-trauma group but deteriorated in 50g㎝ spinal cord-trauma group. 3) The latency of SEP in control group was 12.22±0.7msec and the amplitude of those was 20.00±2.21㎶. No significant statistical change was recorded in the SEP of each spinal cord-trauma group compared to control group. MEP might be more important indicator than SEP in estimation and evaluation of the functional change of spinal cord injury.