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.

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.

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

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.

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.

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.

Rhizopus suinus의 原形質體 融合에 關하여

이영하,김무송,최영길 충남대학교 자연과학연구소 1984 忠南科學硏究誌 Vol.11 No.2

The protoplast fusion of Rhizopus suinus was studied to develope a new method for strain improvement in Rhizopus species. High yields of protoplasts from 12hr-age of germlings were obtained by using an enzyme system containing Bacillus HD 2 chitosanase and commercial Driselase with 0.5M mannitol as osmotic stabilizer. The optimum temperature for mycelium digestion was 25℃ and the optimum pH was 6.0. The reversion frequency of these protoplasts on minimal and complete agar medium was 0.39 and 0.45%, respectively. In the presence of polyethylene glycol (PEG), intraspecific hybrids were aquired by the protoplast fusion between protoplasts of UV induced auxotrophs. Thirty percent of PEG (pH 6.0) was found to be most effective and the efficiency of PEG was enhanced by the addition of 10-50 mM CaCl_2. The average fusion frequency under optimum condition was 0.42%.

濕과 體液의 關係에 對한 實驗的 硏究 : 水液의 腹腔注射와 濕狀態의 比較 硏究 Comparative study on the relations between the abdominal injection of water and damp state in rats

洪茂昌,金完熙,河兌炫 慶熙大學校韓醫科大學韓醫學硏究所 1995 慶熙韓醫大論文集 Vol.18 No.2

Dampness and dryness are the relative concepts of the state which decided by humidity. In the view of Oriental physiology they are the ambient factor stimulate a living body and the phenomenal state decided by the metabolism of body water; pathogenic factors and some kinds of syndrome pathologically. This study attempted to examine whether the damp state(濕狀態) of body can be expressed by bodyfluid volume. 7 weeks old, 280±5g, Sprague-Dawley rats were divided into three groups: normal, sample 1 and sample 2. 0.9% (sample 1) and 0.45% (sample 2) NaCl water solution were injected into the abdomen of each sample group. As the indices of adaptation for the internal environmental changes, blood Hct, serum osmotic pressure and serum electrolytes levels were investigated every 15 min. for an hour. The results were as follows: Serum ?? concentration was increased in sample 1 at 15 and 30 min. after the injection and decreased in sample 2 at 15min.; Serum osmotic pressure appears no change in sample 1, while decreased in sample 2 from 15 to 60 min. From above, it can be concluded the state induced from abdominal injection of 0.45% NaCl ws was more similar to the damp state than the state from 0.95% NaCl ws. The changes were most prominent at 15 and 30 min. and living body appears quick accommodation to these, and thus it recovered almost normally at 60 min. after the injection.

가토의 하악골 연장시 Sodium fluoride 투여가 골형성에 미치는 영향

김용하,설정현,변우목,김정철,우상현,강무석 大韓成形外科學會 1999 Archives of Plastic Surgery Vol.26 No.4

The purpose of this study was to improve bone formation and shorten the period involved in distraction osteogenesis using sodium fluoride (NaF). This has been used in managing osteoporosis for several decades. This study was carried out on 40 New Zealand white rabbits. Twenty animals were used for a control group (no medication) and 20 for the experimental group. NaF 1 mg/kg/day was administered to each experimental animal via drinking water beginning 4 weeks prior to surgery and continued until sacrifice for examination. A distraction device was applied to the left mandible along a plane perpendicular to the direction of osteotomy. After a 5-day latent period, the mandibles were lengthened at 1 mm per 24 hours for 10 days. Five rabbits from each group were sacrificed on the 1st day, 2nd week, 4th week and 8th week of the consolidation period. After lengthening, all the rabbits developed a severe cross-bite. By the 4th week, cortical continuity was seen. Bone densities at the site of bony lengthening were measured by quantitative computer tomography (QCT) and dual X-ray absorptiometry (DXA). The results were as follows: the measurements of the experimental group were significantly higher than of the control group by the 1st day of the consolidation period (p<0.05) and insignificantly higher after the 2nd week. Histologically, in the experimental group, there were more osteoblasts, increased and thickened trabeculae and more mature lamellar bones than in the control group. This study showed that osteogenesis of the experimental group was significantly higher during and immediately after distraction. Our study suggested that the use of NaF could improve bone formation and decrease the period of distraction osteogenesis if a safe dose and method of fluoride administration can be determined for growing humans.

가토의 하악골 연장에서 잠복기간 단축의 영향

김용하,설정현,최준혁,강무석 大韓成形外科學會 1999 Archives of Plastic Surgery Vol.26 No.5

To evaluate the effect of shortening the latent period for distraction osteogenesis, the authors experimented with distraction osteogenesis for a 24-hour latent period in the mandibles of rabbits. This study was carried out on 32 New Zealand white rabbits, each weighting 2000 to 2500 gm. Twenty animals were used for the control group and 12 for the experimental group. A unilateral external fixation device was applied to the left mandible. The mandibles were lengthened at 1 mm per 24 hours for 10 days. Five rabbits from the control group and three from the experimental group by random selection were sacrificed on the first day, and at the second, fourth and eighth week of the consolidation period. After lengthening bone densities at the site of the left mandibular bony lengthening were measured by quantitative computer tomography (QCT) and dual energy x-ray absorptiometry (DXA). As a result, the DXA value showed no difference compared to the control group after two week's consolidation. The trabeculae were thicker and had begun to be surrounded by lamellar bone both in the control and experimental groups histologically. In conclusion, the results of this study indicate that the osteogenetic effect in the experimental group was nearly the same as in the control group. If stable fixation and minimal periosteal dissection were performed during the procedure, the latent period would not be an important factor in distraction osteogenesis of membranous bone.