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.

계면활성제의 친수·소수성 그룹의 부분전하와 CMC 특성 (양이온 및 양쪽성 계면활성제)

하윤식,서무룡 한국환경과학회 2000 한국환경과학회지 Vol.9 No.5

On the basis of theory of Bratsch's electronegativity equalization, the electronegativity equalization, the group electronegativities and the group partial charges for cationic and amphoteric surfactants could be calculated using Pauling's electronegativity parameters. From calculated output, we have investigated relationships between CMC(critical micelle concentration) and partial charge and group electronegativity of hydrophilic and hydrophobic groups, structural stability of micelle for cationic and amphoteric surfactants. As a result, CMC depends upon partial charge and electronegativity of hydrophilic and hydrophobic groups for surfactants. In case of cationic surfactant, as the increment of carbon number in hydrophilic group, partial charge of hydrophilic group is increased, but CMC and electronegativity of hydrophilic group is decreased. With increasing the carbon number of hydrophilic group for cationic surfactant, its partial charge is increased, but CMC and its electronegativity are decreased. With increasing the carbon number of hydrophobic group for cationic and amphoteric surfactant, its partial charge is increased, but CMC and its electronegativity are decreased

環境的 아이덴티티의 認知次元에 관한 硏究

河在明,崔武革 慶北大學校 1991 論文集 Vol.51 No.-

This thesis aims at studying one of the ways which grasps exactly environmental qualities. For this purpose, this paper examines the cognitive dimensions of environmental identity which is the identity that a person or group has with his environment, in particular when he is experiencing it as an insider. There are two important dimensions: the vertical dimension and the horizontal dimension. The vertical dimension is classified by the degree of relationship between the observer and the environment. The horizontal dimension is classified by the scale of the environment concerned with its users.

炎症性 치간조직의 Immunoglobulin濃度

曺武鉉,鄭雲夏 慶北大學校 齒科大學 1984 慶北齒大論文集 Vol.1 No.1

The purpose of this study is to research the immunoglobulin concentrations in the gingiva and the relationship between in immunoglobulin concentrations in periodontal disease. The patients, who came to the Dept. of Periodontics of Kyungpook National University Hospital, were selected for samples. They were suffering from gingivitis and periodontitis through the survey of clinical and radiological examination. Author divided all of them who participated in the experiment into 3 groups: control group, gingivitis group and periodontitis group. Maxillary and mandibular facial gingival specimens were obtained from the three groups of patients during routine treatments. After resection of the gingival tissue (5 x 3 x 3mm), homogenized it with Potter-Elvehjem teflon pestle glass homogenized it and performed the measurement of it's weight to 1/ 100㎎. After that, performed the radial immunodiffusion assay. The results were as follows: In healthy gingiva, IgG concentration was average 8.76㎍/㎎ dry tissue and IgA concentration was average 2.33㎍/㎎ dry tissue. In gingivitis, IgG concentration was average 10.33㎍/㎎ dry tissue and IgA concentration was average 3.58㎍/㎎ dry tissue. was In periodontitis, IgG concentration was average 10.14㎍/㎎ dry tissue and IgA concentration was average 4.56㎍/㎎ dry tissue. IgG concentration in gingiva was increased in gingivitis. IgA concentration in gingiva was increased in periodontitis. IgM was detected two or three of the 16 specimens in healthy and inflamed gingiva.

일가족에 발생한 Microsporum canis 감염증

서무규,성열오,윤기상,하경임 동국대학교 경주대학 1996 東國論集 Vol.15 No.-

Microsporum (M.)canis 감염은 애완용으로 기르는 고양이나 개가 주된 감염원이며 두부 백선, 안면백선 및 체부 백선 등의 피부질환을 일으킨다. 특히 M. canis 가족감염예는 M. canis 감염증중 비교적 드물다. 저자들은 전형적인 임상 및 균학적 양상을 보인 고양이로부터 감염된 M. canis 가족예를 경험하고 문헌고찰과 함께 보고한다. Microsporum canis Infections Occurring in a Family Departments of Dermatology & Clinical Pathology, College of Medicine, Dongguk University Moo Kyu Suh M.D., Yeol Oh Sung M.D., Ki Seong Yoon M.D., Gyoung Yim Ha M.D." We report a case of Microsporum (M.) canis infections occurring in a family. The mother, a son and a daughter had multiple, wen defined, round, scaly erythematous patches on the scalp & face, face & trunk, and face & chest respectively. Culture from skin lesion of patients and an infected kitten on Sabouraud dextrose agar showed M. canis. After 15 days to one month administration of itraconazole, the lesins healed leaving a slight hypopigmentation.

전자선 조사에 의한 국내산 신선돈육의 이화학적 특성 변화

이무하 서울대학교 농업개발연구소 1999 농업생명과학연구 Vol.3 No.-

This study was carried out to examine the effects of electron-beam irradiation on the shelf life of pork loins. The pork loins were aerobically packed by polyethylene films and exposed to an absorbed dose of 0, 05, 1 and 2kGy of electron-beam irradiation at ambient temperature. The irradiated samples were stored together with the nonirradiated samples at 4±2℃. Nonirradiated pork loin began to putrefy after 10 days, while 2kGy irradiated one showed 106 CFU/cm2 after 12 days at 4℃. As the irradiation dose increased, effects of the treatments increased in total plate count, lactic acid bacteria and psychrotrophs. TBA values were apt to increase as the storage period and the irradiation dose increased. VBN value of nonirradiated pork loin was increased rapidly after 7days and that of irradiated treatments increased slowly during the storage period. Redness(a value) and yellowness(b value) of 2kGy irradiated treatment were lower than those of other treatments as the storage period increased. pH value of nonirradiated pork loin showed the increase slow during the storage period. The results of triangle test showed that the degrees of difference were significant between 0.5kGy irradiated treatments and 1kGy irradiated treatments(P 〈0.05) in the cooked pork loin. In the fresh pork loin, degrees of difference were significant between nonirradiated treatment and 0.5kGy irradiated treatment(P 〈0.05) and between nonirradiated treatment and 1kGy irradiated treatment(P〈0.01). In the descriptive analysis with scaling for fresh and cooked pork loin, it was observed that the nonirradiated pork loin scored higher in acceptability than the irradiated. In the fresh pork loin, off-flavor was detected more in 2kGy irradiated treatment than in others.

Ethylenediamine-N, N'-di-α-isobutyric Acid의 Cobalt(Ⅲ) 착물의 합성

전무진,박장우,최승락,박광하 연세대학교 자연과학연구소 1987 學術論文集 Vol.18 No.-

주게전자가 ONNO인 네자리 리간드, ethylenediamine-N, N'-di-α-isobutyric acid(eddib)를 합성하고 이 리간드의 디클로로 코발트(Ⅲ) 착물을 공기산화법에 의하여 합성하였으며 이 착물의 uns-cis이성체와 s-cis이성체를 이온 교환 크로마토그래피법에 의하여 분리하였다. 그리고 eddib의 디클로로 코발트(Ⅲ) 착물을 용액중에서 Co(eddib)L^n+(L=Cl·H_2O,CO_3^2-, (H_2O)_2)로 치환반응을 시켰을때 이들의 전자흡수 스펙트럼의 흡수띠 위치가 분광학적 계열과 일치함을 알 수 있었다. A new flexible N_2O_2-type tetradentate ligand, ethylendiamine-N, N'-di-α-isobutyric acid (eddib), has been synthesized, and dichloro cobalt (Ⅲ) complex of eddib has been prepared via the airation method. The geometric isomers of the complex, s-cis and uns-cis isomers, have been separated through ion exchange chromatographic method. Aseries of cobalt (Ⅲ) complexes of eddib, [Co(eddib)L]^n+ (L=Cl. (H_2O), Co_3^2-, (H_2O)^2) have been prepared in solution. In their electronic absorption spectra, the absorption maxima and their intensities of the above series of complexes are on the ordinary line of the spectrochemical and hyperchromic series. Elemental analysis, IR, NMR and electronic absorption spectra have been used to characterize the complex and geometries of the complex.

浸透水에 의한 모래層의 破壞에 관한 硏究

權武男,李相昊,柳泰夏 慶北大學校 1991 論文集 Vol.51 No.-

In order to investigate seepage failure of sand layer and analyze the effect of the loaded filter constructed on the top of the layer, small scale laboratory tests were carried out on 6 kinds of grain sized sand layers with and without loaded filter of variations of thickness. The results obtained are as follows; 1. The relationship between critical velocity and critical gradient had positive correlation and appears to be linear equation regardless of grain size of the sand. 2. The critical velocity had a trend to increase linearly as grain size of the sand get to be bigger. And the critical velocity in the effective size of 10mm appeared to be about 15 times of that of the 0.2㎜ effective size. 3. The critical velocity was increased according to increase the thickness of loaded filter. And the critical velocity in the 8㎝ thick of loaded filter showed to be 2 times as comparison to the case of no loaded filter. In virtue of the conclusion above, the seepage force can fail sand layer seriously but the stability of sand layers will be able to improve remarkably by construction of loaded filter on the top of the sand layer.

Ethylenediamine-N,N'-di-α-Butyric Acid의 로디움(Ⅲ) 착물

전무진,한창윤,박장우,최승락,박광하 연세대학교 자연과학연구소 1985 學術論文集 Vol.15 No.-

네자리 리간드인 ethylenediamine--N,N'-di-α-butyric acid(eddb)의 디클로로 로디움(Ⅲ)착물을 합성하고 크로마토그래피법으로 분리하였다. Eddb리간드가 로디움(Ⅲ) 이온에 배위될 때 s-cis와 uns-cis기하 이성체가 형성됨이 관찰되었다. 합성된 착물의 구조는 적외선 분광분석법, 핵자기 공명 및 흡수 스펙트럼으로 확인되었다. Dichloro rhodium(Ⅲ) complex of a flexible tetradentate ligand of ethylenediamine-N,N'-di-α-butyric acid(eddb) has been prepared and separated by the chromatographic method. S-cis and uns-cis geometric isomers have been yielded during the preparation of complex. IR, PMR and electronic absorption spectra have been used to characterize the complex.

AO Synthes 금속판을 이용한 전방 경추 유합술후 발생한 지연성 식도 천공

송하헌,김태균,심대무 圓光大學校 醫科學硏究所 1999 圓光醫科學 Vol.15 No.1

Esophageal perforation after anterior cervical discectomy operation has a rare incidence. Also Delayed Esophageal perforation after anterior cervical discectomy has a very rare incidence. Esophageal perforaton is usually characterized as being due to the surgical exposure, metallic implant, bone graft, fractured vertebrae and polymethylmethacrylate. Esophageal perforaton result in fatal mediastinitis, which may lead to die from sepsis. The mortality rate continues to be more than 20%. Factors that adversely affect the outcome include the location and severity of the esophageal injury] associated injuries and delayed diagnosis and treatment. The purpose of this report is to present the our case of a patient who had delayed esophageal perforation by irritation of metallic screw and 3 weeks post operatively, and to know how can we get a early diagnosis and treatment in delayed esophageal perforation.