• The Korean Journal of Nuclear Medicine
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• v.38 no.2
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• pp.161-170
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• 2004

Molecular Nuclear Neuro-Imaging in "CNS" drug discovery and development tan be divided into four categories that are clearly inter-related.(1) Neuroreceptor mapping to examine the involvement of specific neurotransmitter system in CNS diseases, drug occupancy characteristics and perhaps examine mechanisms of action;(2) Structural and spectroscopic imaging to examine morphological changes and their consequences;(3) Metabolic mapping to provide evidence of central activity and "CNS fingerprinting" the neuroanatomy of drug effects;(4) Functional mapping to examing disease-drug interactions. In addition, targeted delivery of therapeutic agents could be achieved by modifying stem cells to release specific drugs at the site of transplantation('stem cell pharmacology'). Future exploitation of stem cell biology, including enhanced release of therapeutic factors through genetic stem cell engineering, might thus constitute promising pharmaceutical approaches to treating diseases of the nervous system. With continued improvements in instrumentation, identification of better imaging probes by innovative chemistry, molecular nuclear neuro-imaging promise to play increasingly important roles in disease diagnosis and therapy.

• The Journal of Korean Medicine
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• v.30 no.5
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• pp.102-114
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• 2009

Objectives: HMCO5 is an extract obtained from 8 different herbal mixtures. We undertook a safety evaluation of HMCO5 for a dose range finding (DRF) toxicity test in specific pathogen free (SPF) Sprague-Dawley (SD) male and female rats. Methods: The male and female rats were divided into 4 groups, respectively; G(0), treated with distilled water: G(1), treated with 222 mg/kg HMC05: G(2), treated with 667 mg/kg HMC05, and G(3), treated with 2,000 mg/kg HMC05; HMC05 was administered orally for 4 weeks. The safety evaluation examined clinical signs, mortality, body weight, food consumption, water consumption, ophthalmic findings, urinalysis, hematological values, absolute & relative organ weights, and necropsy findings during the tests. Results: There were no changes in clinical signs, mortality, body weight, food consumption, water consumption, and ophthalmic findings examined during the test periods. In serum biochemical values, triglyceride was increased in male group G(3) and Na$^+$ decreased significantly in male groups G(2), G(3) and G(4). In male group G(4), spleen weight decreased relatively and increases of absolute & relative left ovary weights were found. In addition, an adhesion of liver to diaphragm was found in male group G(2). However, we could not find any dose-interrelationships in these changes. Conclusions: These results indicate that HMC05 extract did not show any toxicity in the DRF toxicity study. Therefore, it suggests that establishment of 1,000, 333 and 111 mg/kg dosages are moderate in a repeated dose 26-week oral toxicity study of HMC05.

• Journal of Korean Ophthalmic Optics Society
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• v.7 no.1
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• pp.75-78
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• 2002

Thirty three layer $TiO_2/SiO_2$ coating mirrors with high reflectance through a 620~820nm wavelength range have been designed and fabricated by electron beam evaporation method. Multilayer films were deposited on glass(BK7) and sequentially. The high reflector design is based on alternating high and low refractive index layers. $n_H$ and $n_L$ such that a "stopband"(or area of high reflectivity) is created that is centered around the design wavelength. ${\lambda}_0$. The measured transmittance spectrum with an incident wavelength at an incident angle of $40^{\circ}{\pm}7^{\circ}$ exhibited a reflectance of 99.9% at the wavelength of 620~820nm but high peak transmittance in the wavelength region from 700 to 740nm.

• Korean Journal of Pharmacognosy
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• v.49 no.2
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• pp.124-131
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• 2018

Phytolaccae Radix has long been used as a traditional indigenous medicine to cure edema and rheumatism. However, there is insufficient background information on toxicological evaluation of Phytolaccae Radix extract to support the safe use. Therefore, we conducted a series of standardized, OECD and KFDA guidelines compliant in vivo study, to find a dose levels for the 13 weeks toxicity study. The extract of Phytolaccae Radix was administered orally to F344 rats at dose levels of 0, 500, 1000 and 2000 mg/kg/day for 2 weeks. Each group was composed to five male and five female rats. In the result, there were no test article-related adverse changes in clinical signs, body weight, food consumption, ophthalmology, hematology, clinical chemistry, gross finding at necropsy and organ weight examination. Therefore, we recommend that 2000 mg/kg/day is a highest treatment group in 13-week exposure study.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.221-233
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• 1996

This experiment was carried out to study the toxic effect of solublized methylcellulose (MC). Sprague-Dawley rats were dosed with 1%(w/v) MC in 0.9% saline by gavage at a dose of 10ml/kg b.w/day or by intravenous injection at a dose of 5ml/kg b.w/day for 28 days. Clinical signs were observed once a day. Body weights, water and food consumptions were measured and urinalysis was performed several times during the experiment. Rats were sacrificed on days 3, 7, 15 and 28 for hematology, blood chemistry, organ weights and histopathology. The relative weight of the spleen and foamy cells of the spleen were increased in the gavage group. Body weight gain, food consumptions, the values of RBC, Hb, MCH, Hct, serum proteins, glucose, bilirubin, AST, and ALP were decreased in I.V. treatment group. On the other hand, water consumptions, the values of serum cholesterol, creatinine, and BUN were increased. Microscopic findings were granulomas, distended sinusoids, and hypertrophy of Kupffer cells with vacuoles in the liver. Spleen exhibited granuloma, increased extramedullary hematopoiesis, and congestion. Kidney exhibited foamy cells in the glomeruli, distension of the tubules. The findings appeared more severe when the treatment was extended. In conclusion, MC solution is not a safe vehicle for intravenous administration because of the toxic effects on the liver, kidney and spleen. In addition, a long-term and large dosage of oral administration of MC appears to be unsafe also and needs to be investigated further.

• Journal of the Korean Society of Food Culture
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• v.34 no.6
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• pp.801-809
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• 2019

Abeliophyllum distichum Nakai is a deciduous shrub of a flowering plant in Oleaceae. It is an important plant resource and consists of only one species in the entire world. A. distichum Nakai is well known an edible, medicinal herb in its habitat districts, but the toxicological evaluation for the safe use of its extract is still insufficient. The study characterized the toxicity of an Abeliophyllum distichum Nakai ethanol extract in Sprague-Dawley (SD) rats and determined the safe dosage levels in a 13 weeks toxicity study. Abeliophyllum distichum Nakai ethanol extract was orally administered once daily for 2 weeks at 0, 500, 1,000 and 2,000 mg/kg/day to male and female SD rats. while recording the clinical signs of toxicity, body weight, food intake/consumption, eye test and urine analysis. Only the total protein frequency in the urine of male SD rats (p<0.05), the right ovary of the 500 mg/kg group (p<0.01) and the right adrenal gland of the 1,000 mg/kg group (p<0.05) in the female rats showed statistically significant changes. But no toxic effects were noted from repeated-dose administration of the Abeliophyllum distichum Nakai ethanol extract in the SD rats during the observation period. The post-mortem examinations showed no test substance-mediated changes. The hematological analysis and clinical blood chemistry data demonstrated no toxic effects from repeated-dose administration of Abeliophyllum distichum Nakai ethanol extract in the SD rats during the observation period. Based on these results, this data suggests that a dose of 1,000 mg/kg/day is a highest treatment to administer when conducting a further 13 weeks toxicity study.

• Korean Journal of Veterinary Research
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• v.49 no.1
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• pp.23-34
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• 2009

This study was performed to evaluate repeated-dose oral toxicities of Chelidonium majus extract in Fischer 344/N rats. Chelidonium majus extract was administered orally to rats at dose levels of 0, 25, 74, 222, 666 and 2,000 mg/kg/day. Each group consisted of 10 rats of each gender. The Chelidonium majus extract was given once a day, 5 times a week, for 90 day repeatedly. This study was conducted in accordance with the Protocol of Korea National Toxicology Program (issued by National Institute of Toxicological Research) and The Standards of Toxicity Study for Medicinal Products (issued by Korea Food and Drug Administration). In the present study, There were no toxicologically significant changes in mortality, clinical signs, body weight gains, ophthalmoscopy, urine analysis, hematology, serum biochemistry, necropsy findings, organ weights, histopathology, estrus cycle and sperm examination of all animals treated with Chelidonium majus extract. These results suggest that the oral no observed adverse-effect level of the test item, Chelidonium majus extract, in rats is higher than 2,000 mg/kg/day in both genders. The target organs were not established.

• The Korea Journal of Herbology
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• v.32 no.1
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• pp.63-68
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• 2017

Objectives : HT042 is a combination of three herbal extracts from the roots of Astragalus membranaceus, the stems of Eleutherococcus senticosus and the roots of Phlomis umbrosa, which has been demonstrated to increase longitudinal bone growth rate. The aim of this study was to assess the safety of HT042 after repeated oral administration. Methods : A 14-day repeated oral dose toxicity study was conducted using male and female Sprague-Dawley rats. HT042 was administered orally at repeated doses of 500, 1,000 and 2,000 mg/kg/day for 14 days. Clinical signs and mortality were observed daily, whereas body weight and food consumption were recorded weekly throughout the experiment. At the end of the study, blood was taken from the posterior vena cava for hematology and serum biochemistry. All organs of the body surface, subcutis, head, thoracic cavity, and abdominal cavity were observed grossly. Then, the internal organs were removed and weighed. Results : No death occurred and no significant changes in clinical sign, body weight, food consumption and serum biochemistry parameters were observed in male and female rats over the study period. Although there were some alterations in hematologic and necropsy findings, and organ weights, these changes were not considered toxicologically significant. Conclusions : These results suggest that the 14-day repeated administration of HT042 does not produce any significant oral toxicity at doses of up to 2,000 mg/kg/day in male and female rats under the present experimental conditions.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.640-644
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• 2010

하천, 호소 등에서 공사 시 준설작업으로 인해 고탁수가 발생되며 이러한 탁수의 이송 확산은 수환경에 변화를 초래한다. 탁수는 준설작업 시 커터헤드(cutter head)가 해저면에 닿는 순간부터 작동을 멈출 때까지 계속하여 발생하며, 이러한 과정들이 반복되면서 많은 양의 부유토사가 발생하게 되고 고탁수현상이 일어난다. 이렇게 발생한 탁수는 수체흐름에 따라 이송 및 확산된다. 탁수발생은 수중의 빛 투과를 감소시켜 일차 생산자인 부유성 및 부착조류의 생육을 저해하고, 이들의 생산성 감소와 군집구성의 변화는 수서생태계의 먹이사슬을 통해 이들을 먹이로 하는 저서무척추동물과 어류의 현존량 감소와 종 구성에 영향을 미치고, 고농도의 현탁 입자는 어류 아가미에 염증을 유발하거나 점막의 파괴와 감염을 유발하여 치사시킬 수도 있다. 또한 과도한 부유 입자는 하류로 침강되어 하천 바닥에 서식하는 부착조류, 무척추 동물 및 곤충의 생육에 피해를 주고, 이것은 어류의 먹이에 영향을 미쳐 어류 개체수를 감소시키거나 산란된 물고기 알을 매몰시키거나 질식시키는 등 여러 가지 방법으로 수서생물상에 영향을 미치게 된다.(낙동강수계관리위원회, 2005) 따라서 준설작업에 있어 탁수의 이송 확산범위를 사전에 예측하고 국내 실정과 환경여건에 알맞게 적용되고, 실용화될 수 있는 수치모델링에 대한 기반핵심 기술개발이 필요하다. 현재 낙동강에서 진행되고 있는 준설현장에서 발생하는 부유탁수의 이송 확산과정을 이차원 흐름해석모형인 RAM2 모형과 오염물 이송 확산해석모형인 RAM4 모형을 이용하여 수치해석을 하고 분석함으로써 수치해석에 의한 부유탁수의 이송 확산모의 결과가 환경영향 범위를 예측하는 데에 적용될 수 있는지를 알아보고자 한다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.179-179
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• 2006

산업기술의 고도화에 따른 IT 산업의 급속한 발전으로 각종 전자, 정보통신기기에 대해 더욱 소형화 고성능화를 요구하고 있다. 이와 같은 경향에 따라 더욱 향상된 기능을 가지고 각종 소자 부품의 개발과 동시에 유독 물질 발생이 없는 청정생산기술 개발에 대한 요구가 끊임없이 제기 되어 왔다. 이러한 요구에 부응하여 기술들이 개발되고 있으며 그 중의 하나로 잉크젯 프린팅 기술이 연구되고 있다. 특히 Dod(Drop on Demand) 방식의 잉크젯은 가정용 프린터로 개발되어 널리 보급된 기술이지만, 이 기술을 PCB 제조기술에 전용하면 친환경 생산공정으로 부품 성장밀도를 증대 시킬 수 있다. 기존의 PCB 제조기술은 전극과 신호 패턴을 형성시키기 위하여 노광공정과 에칭공정을 반복적으로 사용하고 있는데, 노광공정에서 쓰이는 마스크와 유틸리티 설비 유지 비용의 문제가 대두되고 있다. 노즐로부터 분사된 잉크 액적들의 집합으로 기판위에 점/선/면의 인쇄이미지를 구현하게 된다. 그러므로 인쇄 해상도는 잉크액적 및 인쇄 방법, 기판과의 상호작용에 크게 의존하게 된다. 잉크 액적과 기판의 상호작용에 영향을 미치는 요소로는 잉크의 물리화학적 물성(밀도, 점도, 표면장력), 잉크 액적의 충돌 조건(액적 지름, 부피, 속도), 그리고 기판의 특성(친수/소수성, Porous/Nonporous, 표면조도 등)을 들 수 있겠다. 우선적으로 노즐을 통과해서 분사되는 액적의 크기에 따라 기판위에 형성되는 라인의 두께 및 폭이 결정된다. 떨어진 액적이 기판위에서 퍼지는 것을 UV 조사를 통한 가경화 과정을 통해서 최종적으로 라인의 투께 및 폭을 조절하려고 한다. 따라서 선폭 $75{\mu}m$의 일정한 미세 배선을 형성시키기 위해 액적 크기 조절과 탄착 resist 액적 표면의 UV 가경화 조건으로 구현하려고 한다. 또한 DPI(Dot Per Inch) 조절을 통한 인쇄로 탄착 resist의 두께 확보 후 에칭시 박리되는 현상을 억제 시키려 한다.