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.

Valuation of ecosystem services in the organic carbon of the Pinus densiflora forest at Mt. Namsan, Seoul Metropolitan City

Lee, Eung-Pill,Lee, Soo-In,Jeong, Heon-Mo,Han, Young-Sub,Lee, Seung-Yeon,Park, Jae-Hoon,Jang, Rae-Ha,Hong, Youg-Sik,Jung, Young-Ho,Kim, Eui-Joo,Lee, Sang-Hun,You, Young-Han The Ecological Society of Korea 2019 Journal of Ecology and Environment Vol.43 No.4

Background: Standing biomass, litter production, rate of litter decomposition, amount of litter on forest floor, and amount of soil organic carbon distribution were investigated from March 2016 to November 2018 in order to evaluate the ecosystem value through organic carbon distribution in the Pinus densiflora forest at Namsan, Seoul Metropolitan City. Results: The amount of organic carbon in the Pinus densiflora forest was 261.09 ton C ha^-1 during the research period, and fixed organic carbon in plant through net photosynthesis was 3.2 ton C ha^-1 year^-1. The organic carbon in plant was 62.77 ton C ha^-1 (24.04%), in litter on the forest floor was 3.65 ton C ha^-1 (1.40%), and in soil was 194.67 ton C ha^-1 (74.56%). The value of plant, litter on forest floor, and soil organic carbon distribution were each 6,277,000 won ha^-1, 365, 000 won ha^-1, and 19,467,000 won ha^-1. The value per ton of fixed organic carbon in plant through net photosynthesis was 320,000 won ha^-1 year^-1 and the value of ecosystem services stored in carbon in the Namsan forest ecosystem was about 26.1 million won ha^-1 for 3 years. Conclusions: The results of this study suggest that the pine forests of Namsan rapidly decompose leaves due to the high atmospheric temperature and accumulate a large amount of organic carbon in the soil to provide climate control regulatory service function.

Proliferation Effect of Conditioned Medium Produced by Lymph Node Stromal Cells

Lee, Sang-Han,Moon, Sung-Hoon,Ha, Sang-Chul,Ma, Jin-Yeul,Kim, Min-Sook,Lee, Jin-Man,Kwon, O-Yu Korean Society of Life Science 2002 Journal of Life Science Vol.12 No.1

CS21 lymphoma cells that preferentially metastasize to lymph nodes after s.c. inoculation into BALB/c mice were grown in vitro in the presence of CA12 stromal cells isolated from lymph nodes. To obtain fundamental data on identification and characterization of the soluble factor(s) produced by CA12 stromal cells, we investigated the biological profile of the conditioned medium produced by CAl2 stromal cells. CAl2 conditioned medium has no affinity with Con A. CAl2 conditioned medium is associated with the proliferation of splenic T- and thymic T-cells with-out adding mitogen, although the conditioned medium cannot induce the differentiation of thymocytes. Additionally, we showed that H-7, not HA-1004 inhibits CS21 cell proliferation. These results suggest that CAl2 conditioned medium has a specific soluble factor(s) produced by lymph node stromal cells.

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>

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.

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.

상하악 전치부 치열궁 형태에 대한 새로운 접근 : 한국성인 정상교합자 모델에서

하만희,손우성,양훈철 대한치과교정학회 2001 대한치과교정학회지 Vol.31 No.3

상하악 전치부 치열은 치아의 형태 변위, 선천결손 등에 의해 종종 교합관계나 심미성에 문제점을 나타내게 된다. 이러한 문제점을 극복하기 위해 임상의는 전치부 비율을 진단시 이용하게 되나, 치열중 형태, 견치간 폭경(intercanine width), 치열궁 장경(segment depth)과 치열중 둘레(arch perimeter)에 따른 전치부 비율의 변화로 인해 이러한 비율을 전치부 교합관계 예측에 직접 적용하는데는 한계가 있다. 이에 본 연구에서는 한국성인 정상교합자 모델(남자 : 20쌍, 여자 : 20쌍)에서 상하악 전치부 치열궁 형태를 least square method로 조사하였다. 한국인 정상교합자의 상하악 전치부 치열궁 형태는 다항 함수(polynomial function), 베타 함수(beta function), 하이퍼볼릭 코사인 함수(hyperbolic cosine function) 순으로 곡선 접합(curve fitting)하였으며, 이러한 곡선 접합도는 남녀, 상하악에 관계없이 일정하였다. 또한 곡선접합(curve fitting)된 치열궁 형태를 바탕으로 견치간 폭경(intercanine width), 치열궁 장경(segment depth)과 치열궁 둘레(arch perimeter)간의 상관관계를 구하였다. 이러한 상관관계는 견치간 폭경에 따른 치열궁 형태 예측과 보다 정확한 전치부 비율에 대한 정보를 제공할 것이다. (주요 단어 : 전치부 치열궁 형태, 전치부 비율) Maxillary and mandibular anterior dental arches often have the problems of occlusal relation and esthetics by malformations of teeth, congenital missing, et at. Though the clinician usually use the anterior ratio to overcome this problems, he has the limitation of a direct application this ratio to the prediction of anterior occlusal relationship by the change of anterior ratio as dental arch form, intercanine width, segment depth and arch perimeter. So this study examine maxillary and mandibular anterior dental arch forms by least square method using Korean normal occlusion models(man : 20 casts, woman : 20 casts), Maxillary and mandibular anterior dental arches of Korean normal occlusion models are curve fitted to polynomial function, beta function, hyperbolic cosine function in order. And this accuracy of curve fitting is constant regardless of man/woman and maxilla/mandible. The relationships between intercanine width, segment depth, and arch perimeter based on this curve fitted dental arch form are acquired. This relationships will give the prediction of anterior dental arch form and the information of more accurate anterior ratio according to intercanine width. Key words : Anterior dental arch form, Anterior ratio

3차원 재구성법을 이용한 수복물의 정량적 미세누출도 측정

하상윤,신동훈 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.5

Established microleakage tests have their own disadvantages. In this study, 3D reconstruction method was tried to overcome these disadvantages. Four types of microleakage tests were used and relationships among them were estimated: penetrated dye volume: marginal adaptability: degree of dye penetration and relative penetrated length to cavity wall. Twenty-four Class V cavities were bulk filled with composite (Esthet X) following surface treatments: N group (no treatment): E group (etching only): T group (etching + Prime & Bond NT). 50% silver nitrate was used as a dye solution after thermocycling (5℃ & 55℃, 1.000 times). Teeth were serially ground with a thickness of 0.2 mm. Volume of dye penetration was estimated from a three-dimensionally reconstructed image with a software (3D-DOCTOR). Percentage of margin without gap was estimated from SEM and degree of dye penetration and the relative length of dye penetration to overall cavity wall were also estimated. ANOVA and Scheffe test for dye volume, Kruskal-Wallis and Mann-Whitney test for marginal quality, Spearman's rho test for checking of relationships among methods were used. The results were as follows: 1. Dye penetration could be seen from several directions, furthermore, its volumetric estimation was possible. 2. Reverse relationship was found between dye volume and marginal quality (r = -0.881/ p = 0.004). 3. Very low relationship was seen between dye volume and two-dimensional tests (degree of dye penetration and relative length). However, 2D evaluation methods showed high relationship (p = 0.002-0.054) each other. 4. Three times vertical section could be recommended as a 2D test.

응급의학과 의사가 시행한 상복부 초음파의 정확성

하영록,김훈,유승,정성필,김승환,유인술 대한응급의학회 2002 대한응급의학회지 Vol.13 No.4

Purpose: The purpose of this study is to determine for upper abdominal pain, the accuracy of emergency abdominal ultrasonography (EAU) performed by emergency physicians with limited training. Methods: Two PGY-3 emergency physicians, who had received 2 hours of hands-on training, including the normal anatomy of a biliary system, liver, kindney, spleen, and pancreas, and who had studied the pathologic findings for another month were the subjects of this study. They used a Sonosite 180? to perform EAU on patients with upper abdominal pain within 2 months after training. We determined the agreement between the radiologist’s abdominal ultrasonography(RAU) and EAU by using Kappa statistics. Results: A total of 59 patients were enrolled. The agreement between the EAU and the RAU findings was 0.97, 0.88, 0.79, 0.73, 0.62, and 0.57 for gall bladder (GB) distension, cholelithiasis, GB wall thickening, duct dilatation, choledocholithiasis, and pericholecystic fluid, respectively (p<0.05). Conclusion: The results of EAU, performed by emergency physician with limited training on patients suffering from upper abdominal pain had a significant agreement with the RAU. However, more educations and cautions are warranted for diagnosing pericholecystic fluid and choledocholithiasis.

급성 연쇄상구균 감염후 사구체 신염에 동반된 고혈압 뇌증 1례

하태선,차상훈,이경은,엄정민 충북대학교 의과대학 충북대학교 의학연구소 1999 忠北醫大學術誌 Vol.9 No.2

고혈압성 뇌병증은 고혈압 환자에서 고혈압과 관련된 두통, 경련, 시각장애 및 다른 신경학적 장애를 동반하는 증후군이다. 증례는 13세 여자환아로 급성 연쇄상구균 감염후 사구체 신염에 동반된 고혈압성 뇌병증 환자였다. 내원시 혈압은 150/110 mmHg 였고 내원당시 검사소견상 단백뇨, 혈뇨, C3의 감소 소견을 보였다. 내원 2일째 자기공명영상을 시행하였고 스핀에코 T2 강조영상에서 양 후두엽과 후 측두엽에 고신호의 이상 부위들이 발견되었다. 치료후 실시한 자기공명영상은 정상 소견을 보였다. 본 저자들은 급성 사구체 신염 환자에서 자기공명영상으로 고혈압성 뇌병증을 진단하고 치료한 1례를 문헌고찰과 함께 보고하는 바이다. Hypertensive encephalopathy is a syndrome consisting of headache, seizures, visual changes, and other neurologic disturbances in patients with elevated systemic blood pressure. We experienced a 13-year-old girl who presented with the manifestations of hypertensive encephalopathy in acute post-streptococcal glomerulonephritis. She visited our hospital because of generalized tonic-clonic seizure after severe headache. On admission her blood pressure was 150/110 mmHg and initial laboratory findings revealed proteinuria, hematuria and decreased C3 level and, T2-weighted MR image showed increased T2 signal in both occipital lobes, suggesting cerebral edema. On follow-up MRI, pathologic lesions were improved. We described a case of hypertensive encephalopathy in acute post-streptococcal glomerulonephritis diagnosed by MRI with a brief review of some related literatures.