Preparation of Thermo-Responsive and Injectable Hydrogels Based on Hyaluronic Acid and Poly(N-isopropylacrylamide) and Their Drug Release Behaviors

Ha Dong In,Lee Sang Bong,Chong Moo Sang,Lee Young Moo,Kim So Yeon,Park Young Hoon The Polymer Society of Korea 2006 Macromolecular Research Vol.14 No.1

Copolymers composed of hyaluronic acid (HA) and poly(N-isopropylacrylamide) (PNIPAAm) were prepared to create temperature-sensitive injectable gels for use in controlled drug delivery applications. Semi-telechelic PNIPAAm, with amino groups at the end of each main chain, was synthesized by radical polymerization using 2-aminoethanethiol hydrochloride (AESH) as the chain transfer agent, and was then grafted onto the carboxyl groups of HA using carbodiimide chemistry. The result of the thermo-optical analysis revealed that the phase transition of the PNIPAAm-grafted HA solution occurred at around 30$\∼$33$^{circ}C$. As the graft yield of PNIPAAm onto the HA backbone increased, the HA-g-PNIPAAm copolymer solution exhibited sharper phase transition. The short chain PNIPAAm-grafted HA ($M_{w}$=6,100) showed a narrower temperature range for optical turbidity changes than the long chain PNIPAAm-grafted HA ($M_{w}$=13,100). PNIPAAm-grafted HA exhibited an increase in viscosity above 35$^{circ}C$, thus allowing the gels to maintain their shape for 24 h after in vivo administration. From the in vitro riboflavin release study, the HA-g-PNIPAAm gel showed a more sustained release behavior when the grafting yield of PNIPAAm onto the HA backbone was increased. In addition, BSA released from the PNIPAAm-g-HA gels showed a maximum concentration in the blood 12 h after being injected into the dorsal surface of a rabbit, followed by a sustained release profile after 60 h.

Effect of Non-animal-Derived Nitrogen Sources on the Production of Hyaluronic Acid by Streptococcus sp. KL0188

Lee, Gil-Yong,Ha, Suk-Jin,Jung, Jong-Hyun,Seo, Dong-Ho,Park, Jong-Yul,Kim, Su-Rin,Park, Nam-Woo,Kweon, Dong-Keon,Park, Sang-Hoo,Park, Cheon-Seok The Korean Society for Applied Biological Chemistr 2009 Applied Biological Chemistry (Appl Biol Chem) Vol.52 No.3

Hyaluronic acid (HA) is a linear high-molecular-weight polysaccharide with useful biomedical applications. Streptococcus zooepidemicus, a typical HA-producing bacterium, requires an animal-derived nitrogen source such as tryptone, peptone or sheep blood as a nutrient. Sixteen non-animal-derived (NAD) nitrogen sources were tested as a replacement for the expensive animal-derived nitrogen sources, which may have safety issues. Among the sixteen tested NAD nitrogen sources, a yeast-derived nitrogen source (YE 0251) showed the highest HA productivity, which was equivalent to the control HA production medium containing tryptone in a 5-L jar and in 3,000-L industrial fermentations. In the 3,000-L fermentation, YE 0251 increased cell mass (dry cell weight) and HA production by 11% and 8%, respectively, compared with the control HA production medium. The fmal specific volumetric productivity (0.41 g/L h) was improved by about 70% after reducing the fermentation time from 20 h to 12 h, compared to the conventional production medium.

남산의 소나무림, 신갈나무림, 아까시나무림의 낙엽생산과 토양유기탄소 동태

정헌모 ( Heon Mo Jeong ),김해란 ( Hae Ran Kim ),신동훈 ( Dong Hoon Shin ),이경미 ( Kyoung Mi Lee ),이승혁 ( Seung Hyuk Lee ),한영섭 ( Young Sub Han ),장래하 ( Rae Ha Jang ),이상경 ( Sang Kyeong Lee ),김태규 ( Tae Kyu Kim ),유영한 한국환경생물학회 2013 환경생물 : 환경생물학회지 Vol.31 No.2

남산의 소나무림, 신갈나무림 그리고 아까시나무림에서 2008년 1월부터 2009년 12월까지의 월별 낙엽생산량과 토양의 유기탄소량을 조사하였다. 소나무림은 2008년과 2009년 모두 10월에 낙엽생산량이 가장 많았으며, 2008년 1월과 2009년 12월에 낙엽생산량이 가장 적었다. 신갈나무림은 2008년과 2009년 모두 11월에 낙엽생산량이 가장 많았으며, 2월에 낙엽생산량이 가장 적었다. 아까시나무림은 2008년 11월과 2009년 10월에 낙엽생산량이 가장 많았으며, 2008년 1월과 2009년 12월에 낙엽생산량이 가장 적었다. 이것은 한반도 중부에서 상록성의 소나무림이 낙엽성의 참나무숲 보다 더 일찍 낙엽이 진다는 것을 의미한다. 소나무림과 신갈나무림, 아까시나무림의 2년 평균의 낙엽생산량은 7.07, 6.36, 5.02 ton ha-1로 소나무가 가장 많았다. 소나무림과 신갈나무림, 아까시나무림의 2년 평균의 토양유기탄소량은 76.2, 68.6, 72.5 ton C ha-1로 소나무림에서 가장 많았다. 이처럼 소나무숲에서 높게 나타난 것은 남산에서 신갈나무나 아까시나무를 벌목하여 임목밀도가 줄었기 때문이다. The objective of this study was to estimate dynamics of litter production and soil organic carbon of Pinus densiflora forest, Quercus mongolica forest, and Rhobina pseudo-acasia forest at Mt. Nam as a part of Korea National Long-Term Ecological Research (KNLTER) from 2008 to 2009. Litter production of P. densiflora forest was the highest in October 2008, 2009 and the lowest in January 2008 and December 2009. Litter production of Q. mongolica forest was the highest in November and the lowest in February in 2008 and 2009. Litter production of R. pseudo-acacia forest was the highest in November in 2008 and October in 2009 and the lowest in January in 2008 and December in 2009. It means that leaves of P. densiflora forest shed earlier than deciduous oak forests in Korean central region. An average of litter production for 2 years was 7.07, 6.36, 4.66 ton ha-1 in P. densiflora forest, Q. mongolica forest, R. psuedo-acacia forest, respectively. An average of soil organic carbon matter for 2 years was 88.3, 76.5, 84.2 ton ha-1 in P. densiflora forest, Q. mongolica forest, R. psuedo-acacia forest, respectively.

감초로부터 Glycyrrhizin 추출

이진휘,장향동,최하영,서동호,이성미,김경하 서울産業大學校 1998 논문집 Vol.47 No.1

Glycyrrhiza uralensis계의 원감초 뿌리에서 추출도는 감초는 여러가지 질병의 약제로 널리 이용되어 왔다. 그 주성분인 gliycyrrhizin은 항염증 활성 및 anti-allergic activity를 갖고 있으며 이러한 생리활성은 aglycone β-gliycyrrhetinic acid 의 활성에 의한 것으로 알려져 있고, β-gliycyrrhetinic acid는 steroid 구조와 유사하며, 면역조절 특성을 갖는 것으로 인식되고 있다. 이러한 β-gliycyrrhetinic acid 의 면역조절 활성에 기여하는 인자와 그 경로에 대하여 조사된 바 있다 Glycyrrhizin은 감초뿌리의 주성분중 하나이며, 그외에도 surgars(14%), starches(30%), flavonoids, saponoids, amonoacids, gums 및 essential oil 등을 포함하고 있다. Licorice, the root extract of Glycyrrhiza uralensis, is used as a medicine for various diseases. Antiinflammatory as well as anti-allergic activities have been attributed to one of its main constituents, glycyrrhizin. These activities are mainly ascribed to the action of the aglycome β-glycyrrhetinic acid. βGlyeyrrhetinic acid has a steroid-like structure and is believed to have immunomodulatory properties, To determine whether interference with complement functions may contribute to the immunomdulatory activity of β-glycyrrbetinic acid. its effect on the classical and alternative activation pathways of human complement were investigated. The main constituent found in the root is glycyrrhizin. The plant also contains various sugars(14%), starches(30%), flavonoids, saponoids, aminoacids, gums, and essential oil etc.

정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

A Systematic Review and Meta-Analysis of Arthroscopic Meniscus Repair in Young Patients: Comparison of All-Inside and Inside-Out Suture Techniques

Dong­Geun Kang,Young­Jin Park,Jae­Ha Yu,Jong­Byung Oh,Dong-Yeong Lee 대한슬관절학회 2019 대한슬관절학회지 Vol.31 No.1

Purpose: The purposes of the present study were to review published studies that investigated arthroscopic meniscus repair to treat meniscus injury in young patients and to compare all­inside and inside­out suture techniques.Methods: Various electronic databases were queried for published articles, and this search was updated in August 2017 for evaluating the outcomes of arthroscopic meniscus surgery in young patients. Data search, extraction, analysis, and quality assessment were performed according to the Cochrane Collaboration guidelines, and the clinical outcomes were evaluated using various outcome values in young patients according to suture techniques.Results: Three randomized controlled trials and three prospective comparative studies were included in this systematic review and meta­analysis. There were no significant differences in clinical outcomes such as meniscus healing rate (risk ratio [RR], 1.11; 95% confidence interval [CI], 0.90 to 1.37; I2=39%) and perioperative complications (RR, 0.62; 95% CI, 0.23 to 1.72; I2=43%) between all­inside and inside­out techniques for meniscus repair.Conclusions: The present study shows favorable results for clinical outcomes such as meniscus healing rate and perioperative complications in young patients. Furthermore, based on our results, both all­inside and inside­out meniscal suture techniques are equally effective in these patients.

콩의 동화기관과 수용기관의 능력평가

Suk Ha Lee,Yeul Gue Seung,Seok Dong Kim 韓國作物學會 1995 Korean journal of crop science Vol.40 No.2

콩의 수량에 대한 광합성 기관(source)과 광합성생물 수용기관(sink)이 미치는 영향을 살펴 보고자, 꼬투리의 크기에 비하여 종실 건물면적이 불량한 수집검정콩인 강릉재래 밀 금릉재래, 꼬투리의 비대가 충실한 백운콩 및 수원 168호를 공시하였다. 두 수준의 재식밀도(ha당 55,000, 110,000 개체)와 개화기 이후 등숙 기간 중 차광막을 설치하여 광합성 능력에 관여하는 환경요인을 변화시킴으로써 나타나는 건물중분배 및 개체수량 반응을 분석한 결과를 요약하면 다음과 같다. 1. 지상부 및 종실건물중의 품종간 광합성능력 변화를 위한 재식밀도 및 차광시 처리간 유의적인 차이가 인정되었고 품종 및 처리간 유의적인 상호작용 효과도 있었다. 2. 지상부 총건물중에 대한 종실건물중 비율은 품종간 차이가 인정되어, 수원 168호가 가장 높았으며, 광합성 능력을 변화시키기 위한 처리 가운데 극히 광이 부족한S2 를 제외한 나머지 세 처리간 차이는 없었다. 3. 등숙기간중에수량을 위한 source와 sink 능력을 광합성 기관 제한정도(source limitation value)에 의하여 품종간 비교하여 보면, 꼬투리에 종실이 충분히 면적되는 수원 168호는 source가, 수집검정콩인 강릉재래나 금릉재래는 sink의 기능이 수량에 있어서 제한요인으로 작용하였다

흰물떼새(Charadrius alexandrinus)의 번식 성공에 대한 환경 요인의 영향

이동윤 ( Dong-yun Lee ),이주현 ( Ju-hyun Lee ),성하철 ( Ha-cheol Sung ) 한국환경생태학회 2021 한국환경생태학회 학술대회지 Vol.2021 No.2

The nest fate of plovers have been affected from around environmental factors such as vegetation, sediment grain size and others, because these factors correlate with the camouflage and consistent temperature of nest. The Kentish plover (Charadrius alexandrinus) is known to select nest site where vegetation cover is low to easily detect predators. However, recent studies show that their nest successes positively correlate with vegetation cover rate, because vegetation can hide incubating parents from predators. Therefore, in this study, we investigated the relationships between vegetation cover and nest fate, and between breeding success and other environmental factors (such as, sand, shell etc.). This study was carried out from early March to late July in 2020 at Saemangeum, specifically (1) Mangyeong estuary, Gunsan, Jellabuk-do; (2) Dongjin estuary, Buan, Jellabuk-do. The study area is reclaimed land with sandy coastal environment, and the size of Mangyeong estuary was about 1,011 ha, Dongjin estuary was about 893 ha. Sedges (family Cyperaceae) were the major vegetation in these locations. We analyzed the effect of environmental factors on the breeding success of Kentish plovers. First, we measured five variables in field: nest diameter (cm), nest height (cm), nest slope (°), distance from nest to the nearest vegetation (m), and the height of the nearest vegetation (cm). Then, we obtained the coordinate of each nest with a GPS and measured distance from nest to water resource (m) using satellite map (Kakao map). We also estimated the cover of environmental factors using 1m² quadrat. The quadrat photos were taken by two ways for each nest: 1) centered on the nest within a 1m²; 2) randomly selected two points in 10m distance from a nest. On the analysis of variables in quadrat photo, we measured the 11 variables. First, we measured the cover of nest area (mm²) and the cover of five environmental factors (dry vegetation, vegetation, sand (grain size < 2 mm), shell and other object; mm²) on the quadrat photos of centered on the nest within a 1m². Second, we also measured the cover of five environmental factors in each photo and calculated the average of two photos on the each factor on the quadrat photos of randomly selected two points in 10m distance from a nest. For statistical analysis, we translated variables using “X = log10 (x + 1); X = translated value; x = origin value” before modelling and analyzed using Generalized Linear Model (GLM). The model criteria was Akaike Criteria Information (AIC). Then, we used Mann-Whitney U test to compared variables between successful and failed nests in the best model. All statistical analysis had a significant effect at p < 0.05. We analyzed 285 quadrat photos (95 photos within a 1m² quadrat centered on each nest; 190 photos on the randomly selected points within 10m area from each nest) from 95 nests: 60 nests in Mangyeong (35 successful nests and 25 failed nests); 35 nests in Dongjin (28 successful nests and 7 failed nests). As the results of GLM, the best model was composed not environmental factors, but three nest factors: nest area, nest diameter and nest slope. In this model, nest area and nest diameter were significant (p < 0.05). However, according to Mann-Whitney test, these factors did not differ between successful and failed nests (p > 0.05). Therefore, when researchers studied the effect of nest factors on the breeding success, nest area and nest diameter should be considered together. On the effect of environmental factors, all factors, which included vegetation and dry vegetation cover, did not affect breeding success. Thus, the other environmental factors should be studied to reveal which one affects the breeding success of Kentish plovers.

몬순기후와 복잡지형의 특성을 갖는 광릉 산림유역의 물과 탄소순환에 대한 교차규모 연구로부터의 교훈

이동호 ( Dong Ho Lee ),김준 ( Joon Kim ),김수진 ( Su Jin Kim ),문상기 ( Sang Ki Moon ),이재석 ( Jae Seok Lee ),임종환 ( Jong Hwan Lim ),손요환 ( Yo Whan Son ),강신규 ( Sin Kyu Kang ),김상현 ( Sang Hyun Kim ),김경하 ( Kyong Ha Kim 한국농림기상학회 2007 한국농림기상학회지 Vol.9 No.2

광릉 슈퍼사이트에서 대기와 식생간의 에너지와 물질교환 규명은 지형과 식생의 복잡성으로 인해 많은 기술적인 어려움에 직면하고 있다. 따라서 KoFlux 연구에서는 상호보완적인 다중 분야의 연구를 통해 이러한 어려움을 극복하기 위한 시도를 해 오고 있다. 본 논문에서는 현재 진행중인 KoFlux 연구의 예비결과 중 특히 광릉사이트에서의 물/탄소수지, 물과 탄소순환의 상호관련성 그리고 몬순기후하의 생태계에서 탄소순환에 미치는 수문학적 요인의 중요성에 대해 중점적으로 논의하고자 한다. 광릉낙엽활엽수림의 순생태생산량 (NEP)은 광범위한 생태학적 연구결과에 따르면 약 ~2.6 t C/ha/y로 예상된다. 이를 미기상 플럭스 관측 결과와 함께 고려할 때 광릉 산림은 탄소의 중요한 육상흡원으로서 기능함을 예상할 수 있다. 다양한 생태수문 관측에 의해 규명된 유역단위 물수지에 의하면 연단위 전체강수량의 약 30-40%가 증발산 (ET)에 해당함을 나타내고 있다. 광릉산림의 대표적인 수종인 졸참과 서어나무의 잎에서 얻어진 탄소 안정동위 원소 조성에 근거하여 계산된 식물 성장기간의 평균 물 이용효율(WUE)은 약 ~12 μmol CO2/mmol H2O에 해당된다. 얻어진 증발산량과 물이용효율은 유역단위의 생태계 생산량을 산출하는데 이용될 수 있다. 나이테 성장량과 토양호흡량의 연단위 변화는 강수량과 강수의 패턴에 의해 크게 영향을 받음을 보이고, 이는 몬순기후에 영향을 받는 동아시아 지역 생태계에서 탄소 순환과정이 수문학적 조건과 밀접한 상관관계를 가짐을 지시한다. 연구지역의 공간적 특성을 정량화하기 위해 관측지의 구조 및 기능적 단위를 규명하기 위한 연구가 진행되고 있고 이를 통해 서로 다른 시공간 규모에서 진행되고 있는 연구의 결과물을 체계적으로 연결 통합하고 나아가 보다 광역적인 규모에서 대표적인 물/탄소 수지를 산출하기 위한 연구가 시도되고 있다. KoFlux Gwangneung Supersite comprises complex topography and diverse vegetation types (and structures), which necessitate complementary multi-disciplinary measurements to understand energy and matter exchange. Here, we report the results of this ongoing research with special focuses on carbon/water budgets in Gwangneung forest, implications of inter-dependency between water and carbon cycles, and the importance of hydrology in carbon cycling under monsoon climate. Comprehensive biometric and chamber measurements indicated the mean annual net ecosystem productivity (NEP) of this forest to be ~2.6 t C ha-1 y-1. In conjunction with the tower flux measurement, the preliminary carbon budget suggests the Gwangneung forest to be an important sink for atmospheric CO2. The catchment scale water budget indicated that 30~40% of annual precipitation was apportioned to evapotranspiration (ET). The growing season average of the water use efficiency (WUE), determined from leaf carbon isotope ratios of representative tree species, was about 12 μmol CO2/mmol H2O with noticeable seasonal variations. Such information on ET and WUE can be used to constrain the catchment scale carbon uptake. Inter-annual variations in tree ring growth and soil respiration rates correlated with the magnitude and the pattern of precipitation during the growing season, which requires further investigation of the effect of a monsoon climate on the catchment carbon cycle. Additionally, we examine whether structural and functional units exist in this catchment by characterizing the spatial heterogeneity of the study site, which will provide the linkage between different spatial and temporal scale measurements.

건전지의 본질안전 방폭성 평가에 관한 연구

지승욱,이광식,이동인,박원주,이춘하,김하호 嶺南大學校 工業技術硏究所 1997 工業技術硏究所論文集 Vol.25 No.1

Ignitability of explosive gas mixture by spark of dry cell in case of short circuit by accident was studied for the purpose of evaluation of intrinsically safe characteristics of dry cell that manufactured in Korea. IEC type spark test apparatus, 21±2[vol%] of hydrogen-air mixture, and dry cell that produced in Korea was used for the experiment. The result of this research could be used for design, manufacturing and using the intrinsically safe electrical apparatus.