• 한국환경성돌연변이발암원학회지
• /
• 제21권2호
• /
• pp.77-81
• /
• 2001

Kamijadowhan (KMD), an oriental herbal medicine used for anti-angiogenic effect, was extracted with 80% ethanol from mixture of source materials and lyophilized. KMD was orally administered to plugpositive pregnant rats from gestational days 12 to 20, dividing into three groups including vehicle-treated control, 0.5 g/kg or 3 g/kg KMD-treated groups. Dam weight during gestation and post-gestation, weight of pre- and post-weaning offsprings in male and female, and reproductive and developmental endpoints including incisor eruption, eye opening and testes descent were measured. No significant alterations in development of physical landmarks in offspring, maternal weight gain during gestation and post-gestation, and offspring weight were observed in KMD-treated group. The measurement of organ weight at post-gestational days 21 was not changed in dams. In 0.5 g/kg KMD-treated rats, kidney weights in male and female offsprings were significantly increased, and the body weight in male offspring was also increased. Liver and brain weights were not changed. Taken together, these data suggest that KMD may not significantly cross the placenta and produce no reproductive and developmental toxicity at maternally non-toxic dosages.

• Toxicological Research
• /
• 제21권1호
• /
• pp.23-29
• /
• 2005

A developmental study of CONP01, a new antiarthritic agent, was conducted in Sprague-Dawley rats. Dosage of CONP01 0, 111, 333, and 1000 mg/kg/day were administered to dams orally from day 6 to day 16 of gestation. Two-third of dams per group were subjected to caesarean section on day day 20 of pregnancy for examination of their fetuses, and the remaining one-third of dams per group were allowed to deliver naturally for postnatal examination of their offspring. There was no change in the dams body weights, food consumptions, specific clinical sings and gross findings. There was significant decrease only in the absolute and relative weights of right ovary in 111 mg/kg treatment group, when compared with the vehicle control, whereas other organ weights were not changed. Moreover, no increase in the frequencies of external, visceral and skeletal malformation of fetuses were observed in the treated groups. These results suggest that the oral NOAEL (no observed adverse effect level) of CONP01 may be over 1,000 mg/kg in dams and fetuses of rats.

• 대한수의학회지
• /
• 제48권4호
• /
• pp.413-421
• /
• 2008

It was previously found that PG102, a water-soluble extract derived from Actinidia arguta, was able to modulate Th1/Th2 pathways and suppress IgE production resulting in dramatic amelioration of atopic dermatitis in NC/Nga mouse and hairless rat models. In order to evaluate the subacute toxicity of PG102, female and male SD rats were daily fed with various doses of PG102 for 4 weeks. Six week old SD rats were randomly divided into 4 groups and orally administrated with 100-, 300-, and 1,000- mg/kg of PG102 as well as the vehicle only. At the end of the study, no significant differences in the body and organ weights were observed between control and treated rats of both genders. Hematological and blood chemical analysis showed little differences between the animal groups. Neither gross abnormalities nor histopathological changes were found. PG102 produced little or no subacute toxicity and could be used as a safe nutraceutical for the treatment of individuals with allergic diseases including atopic dermatitis.

• Composites Research
• /
• 제18권6호
• /
• pp.19-25
• /
• 2005

본 논문에서는 하이브리드 복합재 틸팅차량 차체에 대한 시험적 연구를 수행하였다. 시험에 적용된 하이브리드 복합재 틸팅차량 차체는 길이가 23m이며 40mm두께의 알루미늄 하니콤 코어와 2mm의 직조된 탄소/에폭시 면재로 구성된 샌드위치 구조물이다. 하이브리드 복합재 틸팅차량 차체의 구조적 거동과 안전성을 규명하기 위해 수직하중- 차단압축하중, 비틀림하중 및 3점지지 하중조건하에서 정적인 하중시험을 수행하였다. 시험은 JIS E 7105규격에 근거하여 수행되었다. 시험을 통해 수직하중하에서 최대처짐은 최대 12.3mm이며 굽힘강성은 $0.81\times10^{14}\;kgf{\cdot}mm^2$로 도시철도차량성능기준을 만족하고 있었다. 또한 강도 측면에서도 탄소/에폭시 면재의 파단변형률의 $20\%$ 이내로 안전도를 만족하였다.

• 한국산학기술학회논문지
• /
• 제12권3호
• /
• pp.1091-1097
• /
• 2011

본 논문은 자동차용 시트의 내부에 설치되어 탑승자의 등 부위를 지지하여 편안한 승차감을 제공하는 자동차용 시트의 플라스틱 서스펜션 어셈블리 개발에 관한 것이다. 운전자의 허리를 균등하게 지지하여 주는 구조를 갖도록 설계하고 시트 백 프레임과 플라스틱 서스펜션이 원활하게 조합될 수 있는 구조로 개발하고자 한다. 체압 분포 특성을 고려하여 서스펜션의 단품을 설계하고 기능성을 평가하였다. 또한 실제와 동일한 사이즈의 서스펜션을 모델링하고 구조해석을 수행하였다. 기존 스프링 서스펜션과 새로 개발된 플라스틱 서스펜션의 해석결과 및 실제 측정값이 유사함을 확인하고 최적의 해석 및 설계를 확립하였다.

• 한국응급구조학회지
• /
• 제17권3호
• /
• pp.9-20
• /
• 2013

Purpose: This research project addressed the need to designing more safe and efficient interior of the future ambulance in Korea. Methods: The study sample contained 760 paramedics in 4 districts. Data was collected by using a revised and complemented questionnaire based on literature review. Results: In relation to the efficacy and safety of work, answers related to storage closet showed to be the highest, and the most difficult part of paramedic work in an ambulance was lurching. CPR is the most frequently used emergency care inside an ambulance, but 66% of the paramedics responded that accurate CPR is not possible during vehicle transfer. Safety belts are not worn for 82.8% of the time, because of discomfort (51.3%). 13.8% of the paramedics responded that stretchers are unstable, 29.5% had an experience of having patients fall off the stretcher inside an ambulance. There were comments on installing equipments to prevent noise, and assist communication. Conclusion: The suggested practical layout contains five main modifications 1. Developing specially designed belt is needed for paramedic safety & efficient work. 2. The seats are molded to be ergonomically friendly. 3. Equipments to secure the body and safety devices for CPR are needed. 4. System improvement for communication between the driver seat and paramedics is needed. 5. The stretchers are molded to be maximize efficiency and minimize injury.

• 대한한의학회지
• /
• 제33권2호
• /
• pp.1-10
• /
• 2012

Objectives: This study was aimed to investigate the effect of Bojungikgitang-gagambang (BJIG) on longitudinal bone growth in rats. Methods: The BJIG treated group (300 mg/kg) and the control group (vehicle) were administered orally twice daily for 4 days. To investigate the effects of BJIG we measured body weight gain. The bone growth effect was analyzed by measuring between fluorescent lines marked with tetracycline, which plays the role of fluorescent dye on the surface of the tibia. Tetracycline was intraperitoneally injected. The height of growth plates in the epiphyseal plate was measured. The expression of bone morphogenetic protein-2 (BMP-2) and insuline-like growth factor-1 (IGF-1) was investigated by immunohistochemistry. Results: BJIG caused a significant acceleration of longitudinal bone growth of $349.7{\pm}15.9{\mu}m/day$ compared to control ($319.8{\pm}21.4{\mu}m/day$). The height of overall growth plate was not significantly more compared to the control, but the size of cells in the proliferative zone and hypertrophic zone were. In the immunohistochemistry, BMP-2 and IGF-1 were expressed markedly in the proliferative or hypertrophic zone, respectively. Conclusions: BJIG stimulated the chondrocyte hypertrophy and chondrogenesis in the growth plate and directly increased the longitudinal tibia length of rats.

• BMB Reports
• /
• 제47권9호
• /
• pp.506-511
• /
• 2014

We investigated the effects of high calorie and low calorie diets on skeletal integrity, and whether ${\beta}$-adrenergic blockade (BB) attenuates bone loss induced by dietary calorie alteration. Male 6-week-old C57BL/6 mice were assigned to either an ad-lib fed control diet (CON), a high calorie diet (HIGH), or a low calorie diet (LOW) group. In each diet group, mice were treated with either vehicle (VEH) or propranolol, a ${\beta}$-adrenergic antagonist. Over 12-weeks, ${\beta}$-blockade mitigated body weight and fat mass increases induced by the high calorie diet. Femoral trabecular bone mineral density and the expression levels of osteogenic marker genes in bone marrow cells were reduced in HIGHVEH and LOWVEH mice, and BB significantly attenuated this decline only in HIGH mice. In summary, the magnitude of bone loss induced by low calorie diet was greater than that caused by high calorie diet in growing mice, and ${\beta}$-blockade mitigated high calorie diet-induced bone loss.

• 대한기계학회논문집A
• /
• 제35권3호
• /
• pp.235-240
• /
• 2011

모함에 연결되어 통신 케이블의 가이드 역할을 하는 탄성 호스는 모함의 운동 조건을 결정하는 중요한 인자이다. 길이가 수 십 미터에 달하는 탄성 호스를 실제 상황에서 실험을 하기에는 어려움이 있으므로 해석을 통해 거동 특성을 분석하고자 한다. 탄성 호스는 곡률 반경에 대한 변형뿐만 아니라 축 방향에 대한 변형도 발생하므로, 축 방향에 대한 변형 구배가 좌표계에서 유도되는 절대 절점 좌표계로 모델링하였으며, 연속체 역학 개념을 도입함으로써 대변형 효과를 표현하도록 하였다. 탄성 호스의 끝 단에 연결된 모함은 강체 모델로 표현하였고, 조향각에 의해 운동이 결정되도록 하였다. 또한, 수중에서 호스가 거동할 때 발생하는 유체 저항력을 고려함으로써 수중에서의 탄성 호스 거동 특성을 분석 하였다.

• 생약학회지
• /
• 제40권4호
• /
• pp.339-344
• /
• 2009

Diabetic cataract is a major complication of diabetes mellitus. Excess accumulation of sorbitol plays an important role in the pathogenesis of diabetic complications such as cataract formation. In this study, we investigated the inhibitory effect of the extract of the aerial parts of Aster koraiensis (AK) on diabetic cataractogenesis. To examine this further, we evaluated sorbitol accumulation during cataract development using streptozotocin-induced diabetic rat, an animal model of type 1 diabetes. Diabetic rats were treated orally with AK (100 mg/kg and 200 mg/kg body weight) once a day orally for 9 weeks. In vehicle-treated diabetic rats, lens opacity was increased, and lens fiber swelling and membrane rupture were observed. In addition, sorbitol accumulation in diabetic lens was markedly enhanced. However, AK treatment delayed the progression of diabetic cataract through the inhibition of sorbitol accumulation, and prevented lens fiber degeneration in a dose-dependent manner. These observations suggest that AK treatment can delay the progression of lens opacification in the diabetic rats during the early diabetic cataractogenesis.