Rheology of Decamethylceclopentasiloxane (cyclomethicone) W/O Emulsion System

Choi, Min-Hyung,Jeong, So-Ra,Nam, Sang-In,Shim, Sang-Eun,Chang, Yoon-Ho The Polymer Society of Korea 2009 Macromolecular Research Vol.17 No.12

A highly dispersed W/O emulsion of silicone oil (cyclomethicone)/water system was prepared with a nonionic surfactant. The surface and interfacial tension between the oil and water were characterized in terms of the droplet size distribution and viscosity change of the emulsion. When the dispersed phase concentration was relatively high, the viscosity of the emulsion was rapidly increased and the droplet size of the emulsion was decreased. The rheological behavior of the emulsion system showed non-Newtonian and shear thinning phenomena depending upon the content of the dispersed phase. The droplet size of the emulsion was decreased with increasing surfactant content and water concentration. The relative viscosity of the emulsion was better predicted with the Choi-Schowalter model than with the Taylor model. The value of the complex modulus increased with increasing surfactant concentration. The linear viscoelastic region was expanded with a dispersed phase concentration. According to the change in the viscosity, the behavior was classified into three distinct regions: [I] linear viscoelastic, [II] partially viscoelastic, and [III] viscous. The creep/recovery behaviors in each region were characterized.

(±)-Camphor가 ICR 마우스 수컷의 간 cytochrome P450 효소 활성에 미치는 영향

오은경,박형건,배기현,최옥진,최은경,최창근,한진희,정태천 한국환경독성학회 2002 환경독성보건학회지 Vol.17 No.4

Effects of (±)-camphor on liver cytochrome P450 enzymes were investigated in male ICR mice. Mice were treated intraperitoneally with 0, 200, 400 and 800 mg/kg of (±) -camphor in corn oil for 3 consecutive days. Twenty four hr after the final treatment, the animals were subjected to necropsy. The activities of serum aspartate aminotransferase and serum alanine aminotransferase were slightly changed by the treatment with (±)-camphor at the doses used. Administration o(±)-camphor to mice significantly induced the hepatic activities of pentoxyresorufin O-depentylase and benzyloxyresorufin O-debenzylase and weakly induced ethoxyresorufin O-deethylase in dose-dependent manners. The present results suggested that (±)-camphor might act as a relatively specific inducer of hepatic cytochrome P450 213 in male ICR mice.

Effects of Phenytoin and Diazepam on the Seizure Activity in the Cortical Dysplasia Animal Models

Kim, Si-Hyung,Choi, In-Sun,Cho, Jin-Hwa,Park, Eun-Ju,Jang, Il-Sung,Choi, Byung-Ju,Kim, Hyun-Jung,Kim, Young-Jin,Nam, Soon-Hyeun The Korean Academy of Oral Biology 2006 International Journal of Oral Biology Vol.31 No.2

Dysplasia-associated seizure disorders are markedly resistant to pharmacological intervention. Relatively little research has been conducted studying the effects of antiepileptic drugs(AEDs) on seizure activity in a rat model of dysplasia. We have used rats exposed to methylazoxymethanol acetate(MAM) in utero, an animal model featuring nodular heterotopia, to investigate the effects of AEDs in the dysplastic brain. Pilocarpine was used to induce acute seizure in MAM-exposed and age-matched vehicle-injucted control animals. Field potential recordings were used to monitor amplitude and numbers population spikes, and paired pulse inhibition in response to stimulation of commissural pathway. Two commonly used AEDs were tested: diazepam 5, 2.5mg/kg;phenytoin 40, 60mg/kg. Diazepam(DZP) and phenytoin(PHT) reduced the amplitude of population spike in control and MAM-exposed rats. However, the amplitude of population spike was nearly eliminated in control rats as compared to the MAM-exposed rats. Pharmaco-resistance was tested by measuring seizure latencies in awake rats after pilocarpine administration(320mg/kg, i.p.) with and without pretreatment with AEDs. Pre-treatment with PHT 60 mg prolonged seizure latency in control rats, but not in MAM-exposed animals. The main findings of this study are that acute seizures initiated in MAM-exposed rats are relatively resistant to standard AEDs assessed in vivo. These data suggest that animal model with cortical dysplasia can be used to screen the effects of potential AEDs.

다발성 간종괴의 형태로 나타난 특발성 과호산구 증후군 치험1예

최승오,연규민,이승민,김순제,왕준호,박형석,이재동,진춘조,이창훈,신현준,김정은 건국대학교 의과학연구소 2004 건국의과학학술지 Vol.14 No.-

Hypereosinophilic syndrome is characterized by persistent blood eosinophilia of 1,500/ul or more in the absence of known causes and multiorgan dysfunction by eosinophil-related tissue damage. In Korea, some cases of hypereosinophilic syndrome with hepatic involvement have been described with prolonged benign clinical courses. Most of them were diffuse or multifocal lesions in imaging studies, and a few case presenting as a single mass has been described. Here we report a case of hypereosinophilic syndrome with hepatic involvement in a 65-year-old man who presented with multifocal mass lesions. By abdominal US and CT scan, multiple, ill-defined nodules were detected in throughout the liver. Liver biopsy revealed severe eosinophilic hepatitis, suggestive of hypereosinophilic syndrome. Hepatic mass lesions improved after steroid administration for several weeks.

수평 매복된 상악 견치의 교정적 견인

최형준,이종은,이제호,이종갑 大韓小兒齒科學會 2003 大韓小兒齒科學會誌 Vol.30 No.4

치아 매복은 구강점막이나 악골내에서 치아의 맹출이 중지된 상태를 의미하며, 제 3구대구치와 상악 견치에서 호발한다. 상악 견치의 매복은 주로 측절치가 상실되거나 왜소한 경우와 연관성이 높지만 치배의 위치 이상과 같이 유전적인 요소와도 관련될 수 있다. 매복치는 심미적, 기능적으로 여러 가지 문제점을 야기하므로 조기에 진단하여 치료하는 것이 중요하며, 매복치의 상태에 따라서 치료 방법을 적절하게 선택하여야 한다. 본 증례는 11세 여아에서 구개측으로 수평 매복된 상악 우측 견치의 치료를 보고한 것으로, 매복치는 외과적 수술을 동반한 교정적 견인 방법을 사용하여 기능적, 심미적으로 회복되었다. 견인 치료는 매복 견치의 맹출 공간을 확보하면서 이루어졌으며, 치료 종료 후 매복 견치는 치근 흡수와 같은 합병증 없이 적절한 부착치은을 확보하여 양호하게 위치되었다. Tooth impaction is defined as a cessation of the eruption of a tooth at the level of the oral mucosa or alveolar bone. Maxillary canines are the most frequently impacted teeth next to the third molar. Maxillary canine impaction is associated with congenital missing of lateral incisors, peg lateralis and genetic factors such as ectopic positioning of a tooth germ. The clinicians have an important role in early detectionof tooth impaction for prevention of esthetic and functional problems. There are specific methods to treat impacted tooth for different conditions. In this case, an 11-year-old girl with a horizontally impacted maxillary right canine in a palatal position was treated through orthodontic traction along with surgical button attachment procedure. On regaining of eruption space, canine traction was performed. At the completion of treatment, the canine was positioned fairly within the arch with proper keratinized gingiva and complications such as root resorption were not observed.

호흡율 측정기를 이용한 폐수의 외부탄소원 이용가능성 평가

최은희,고주형,임정훈,부경민,김창원 부산대학교 환경문제연구소 2000 環境硏究報 Vol.18 No.-

In this research, we measured Readily Biodegradable COD(Ss) using respiration meter which measured OUR and calculated respiration rate due to calculate organic matter portion of external carbon sources because known organic matter analysis methods i.e. COD, BOD did not measure amount of organic matter which was used in denitrification. Based on the experimental results, leather wastewater had 40.3% Ss in TCOD and food fermentation liquid, alcoholic wastewater and petrochemical wastewater was 38%, 38% and 28.3% respectively. However in case of considering of flowrate and concentration, flood fermentation and alcoholic wastewater was revealed that they were effective external carbon sources

폐모세포종 : 1례보고 A Case Report

최영호,서홍주,임영혁,김정중,박성강,이석기,임진수,김은규 조선대학교 2001 The Medical Journal of Chosun University Vol.26 No.2

Pulmonary blastoma is a very rare primary neoplasm of the lung. We experienced a case of pulmonary blastoma in a 40 years old man. The mediobasal segmentectomy of the right lower lobe was performed. The patient was discharge on the postoperative days 6. There is no evidence of recurrence or metastasis on followup study during 7 months period after operation.

2-Bromopropane이 암컷 골든 햄스터의 생식기능에 미치는 영향

최돈찬,최형재,박창은 龍仁大學校 2000 용인대학교 논문집 Vol.18 No.-

Ovarian dysfunction induced by 2-bromopropane(2-BP) has been described in female factory workers and experimental animals. However, the underlying mechanism is still unclear. 2-BP is the possible causative chemical for reproductive and hematopoietic toxicity. To clarify the effect of 2-BP on the female reproductive function, repeated doses of 2-BP were administered to female golden hamsters for 24 days. Following 2 completed estrous cycles, animals received subcutaneously vehicle(corn oil), 80mg/kg, 400mg/kg, 2000mg/kg of 2-BP for 8 days. The females were then mated with males. The treatment continued for a gestation period(16 days). Dams treated with 2-BP showed a significant decrease in body weight. 2-BP decreased the fertility and tended to decrease the number of pups born and the rate of pregnancy, depending on the dose. The eccentric pyknotic cells, shrinkage of oocyte, and scattered cells were appealed in the middle and higher dose groups. The results indicate that reproductive toxicity induced by 2-BP was dose-dependent in that the higher doses exhibited more severe toxicity than the lower doses in our 24-day repeated dose experiments. Thus, 2-BP as a endocrine disrupter affects female reproductive activity to cause the destruction of primordial follicle and its oocyte in the ovary.

간흡충 감염증의 진단에서 피내반응 검사의 유용성 검토

최재철,오승환,정해진,신정환,박기형,이은엽,장철훈 대한임상미샐물학회 2003 Annals of clinical microbiology Vol.6 No.2

수컷 골든 햄스터에서 광주기에 따른 Gonadotropin Releasing Hormone 유전자 발현

최돈찬,박창은,최형재 용인대학교 자연과학연구소 2000 自然科學硏究所論文誌 Vol.5 No.1

The sexual activity of golden hamsters is controlled by photoperiod(light/day), being active in summer and inactive in winter. Adult hamsters in a short day(SD, ≤12 hours of light/day) show gonadal regression at about 8 week regardless of sex. The regressed testes display remarkably lowered follicle-stimulating hormone and luteinizing hormone levels in blood. The synthesis and release of gonadotropins are well established to be regulated by the gonadotropin releasing hormone(GnRH). Thus, it is thought that SD curtails the release of GnRH. Removal of pineal gland always sustains the sexual activity. A proper treatment of melatonin, a major hormone secreting from the pineal gland, suppresses the sexual function, indicating the mediation by melatonin. Thus the expression of GnRH gene was examined in the hypothalamus depending on photoperiods in male golden hamsters. As results, GnRH gene was partially identified and detected concurrently in the preoptic area and mediobasal hypothalamus. Thus, photoperiod appeared not to affect the expression of GnRH gene. But the effects of SD was blocked by the removal of pineal gland. These results suggest that photoperiod and pineal gland do not affect the experession of GnRH gene but may affect the releasing mechanism of GnRH from hypothalamus of male golden hamsters.