• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2004년도 추계학술발표회 발표논문집
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• pp.1135-1135
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• 2004

• Toxicological Research
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• 제4권2호
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• pp.181-188
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• 1988

This study was carried out to investigate whether the use of the high endotoxin-sensitive or the low endotoxin-sensitive rabbits (New Zealand White strain) are more suited for the pyrogen test regulated by the Korean Pharmacopeia and United State Pharmacopeia. The results obtained were as follows. 1. The ferbrile responese were increased according to increased endotoxin doses used (i.e., 0.1, 1, 5, 10ng/kg) and the febrile responses reached to its maximum between 90 mins and 120 mins after the intravenous injection of endotoxin.

• 한국콘텐츠학회논문지
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• 제12권10호
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• pp.340-348
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• 2012

흉부영역에서 토모신테시스 검사의 유용성 평가를 위하여 흉부단순검사와 저 선량 CT, 토모신테시스를 실시하여 흡수선량을 비교하고 영상을 평가하였다. 흉부단순검사의 흡수선량은 $0.33{\pm}0.27$ mGy 이었으며, 저 선량 CT는 $1.26{\pm}0.56$ mGy, 토모신테시스는 $0.55{\pm}0.02$ mGy로 검사별 흡수선량 간에 유의한 차이를 보였다(p<0.001). 영상의 평가결과 단순검사 점수는 각각 $1.66{\pm}0.72$, $1.61{\pm}0.63$, $1.57{\pm}0.73$ 이었으며 저 선량 CT는 $2.92{\pm}0.26$, $2.91{\pm}0.29$, $2.88{\pm}0.32$ 이었고, 토모신테시스는 $2.69{\pm}0.51$, $2.76{\pm}0.43$, $2.66{\pm}0.61$로 검사에 따라 통계적으로 유의한 차이를 보였으나(p<0.001), 저 선량 CT와 토모신테시스 사이에는 유의한 차이를 보이지 않았다. 토모신테시스는 흉부영역의 검사 시 환자의 피폭선량을 최소화하고 진단의 효과를 높일 수 있는 유용한 검사라고 생각된다.

• Biomolecules & Therapeutics
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• 제7권4호
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• pp.322-328
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• 1999

In this study, it was tested whether the changes of catecholamines and its metabolites are related with the changes of blood pressure(BP) induced by different levels of lead exposure. Adult male SD rats were exposed to lead by giving drinking water containing 50(low doses), 200 and 1,000 ppm(high doses) of lead(as lead acetate) or sodium acetate(for control groups, supplying an identical amount of acetate) for 7 or 16 weeks. The systolic BP was measured in the unanesthetized state by the tail-cuff technique. Levels of catecholamines and its metabolites in urine were measured by HPLC-ECD. Rats receiving 200 and 1,000 ppm developed an elevation of systolic BP at 3 and 7 weeks compared with week 0, but blood pressure levels at 16 weeks returned to normal. For the 50 ppm lead treated group, systolic BP increased significantly at 7 weeks and 16 weeks. The concentrations of norepinephrine and VMA in the urine of lead exposed rats changed similarly to the changes of blood pressure, but blood viscosity levels in all lead treated rats increased continuously during all lead treatment periods. This result suggests that the changes of catecholamines and its metabolites in urine by lead intoxication may influence the changes of blood pressure.

• Toxicological Research
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• 제16권1호
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• pp.83-87
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• 2000

This study was carriet out to evaluate the acute intravenous toxicity and antigenicity of Guamerin, newly developed by Mogam Biotechnology Research Institute (MBRI). In acute intravenous toxicity test, ICR mice were administered intravenously with single dose of 1,000mg/kg, and body weights and clinical signs were observed for 14 days. No dead animal, clinical signs, body weight change and abnormal autopsy findings were found in control and Gumerin treated group. Therefore, the 50% lethoal dose (LD50) of Guamerin for ICR mice was more than 1,000mg/kg on intravenous route for male and female. And the antigenic potential of Guamerin was examined by active systemic anaphylaxis(ASA) and passive cutaneous anaphylaxis(PCA) tests. In the ASA test, low and high doses (10 and 100ug/animal, respectiwely) of Guamerin were administed subcutaneously to guinea pigs for 9 times 3 weeks. All experimental groups showed negative responses whereas the positive control group given ovalbumin plus Freunds complete adjuvant (FCA) showed severe anaphylactic responses. PCA test using rats with mice anti-serum against Guamerin, low and high doses(10 and 100 ug/animal, respectively) of Guamerin were administered to mice for 9 times in 3 weeks. The anti-serum against Guamerin was administed intradermally at the back of rats, however, any positive responses were not detected in the experimental groups. These results strongly indicate that Guamerin does not induce IgE production and is not a PCA reaction inducer under these experimental conditions.

• Biomolecules & Therapeutics
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• 제6권2호
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• pp.165-170
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• 1998

Antigenic potential of DW-116, a newly synthesized fluoroquinolone, was examined by conduc-ting active systemic anaphylaxis (ASA), passive cutaneous anaphylaxis (PCA) and passive hemagglutination (PHA) tests. In ASA test, mild to moderate signs of anaphylactic responses were observed in the groups sensitized with low (2 mg/body) and high (10 mg/body) doses of DW-116 alone and the group sensitized with DW-116 plus adjuvant. Some moderate to severe anaphylactic reactions were observed in the group sensitized with a DW-116-bovine serum albumin (BSA) conjugate plus adjuvant when challenged with a DW-116-guinea pig senHn albumin (GSA) conjugate. However these reactions were considered to be a cross-reaction between BSA and GSA since similar reactions were induced when challenged by GSA alone. In heterologous PCA test using mice and rats, positive responses were not detected in any of the experimental groups. In PHA test, positive responses were observed in the groups sensitized with low and high doses of DW-116 alone and the group sensitized with DW-116 plus adjuvant. However, these responses were not considered to be drug-specific because some positive responses were also seen in the negative control group. From these results, it was concluded that DW-116 is not likely to have specific antigenic potential in clinical use.

• Molecular & Cellular Toxicology
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• 제1권3호
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• pp.203-208
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• 2005

Thioacetamide (TA) is potent haptotoxincant that requires metabolic activation by mixed-function oxidases. Micrcarray technology, which is massive parallel gene expression profiling in a single hybridization experiment, has provided as a powerful molecular genetic tool for biological system related toxicant. In this study we focus on the use of toxicogenomics for the determination of gene expression analysis associated with hepatotoxicity in rat liver epithelial cell line WB-F344 (WB). The WB cells was used to assess the toxic effects of TA. WB cells were exposed to two concentrations of TA-doses which caused 20% and 50% cell death were chosen and the cells exposed for periods of 2 and 24 h. Our data revealed that following the 2-h exposure at the both of doses and 24-h exposure at the low doses, few changes in gene expression were detected. However, after 24-h exposure of the cells to the high concentration, multiple changes in gene expression were observed. TA treatment gave rise predominantly to up-regulation of genes involved in cell cycle and cell death, but down-regulation of genes involves in cell adhesion and calcium ion binding. Exposure of WB cells to higher doses of the TA gave rise to more changes in gene expression at lower exposure times. These results show that TA regulates expression of numerous genes via direct molecular signaling mechanisms in liver cells.

• Asian-Australasian Journal of Animal Sciences
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• 제23권1호
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• pp.13-16
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• 2010

The effect of exogenous administration of tamoxifen (TAM) on hormonal profile and sexual maturity in Indian native Kadaknath (KN) fowl was investigated. Day-old chicks from the same hatch were randomly divided into 15 groups with 20 chicks in each group (5 treatments${\times}$3 replicates). The chicks were placed in battery brooders with wire-mesh floors and reared under uniform husbandry conditions (14 h light/d, 25-32${^{\circ}C}$) on a standard basal diet. At the age of two weeks (wk), birds from the control group ($T_{1}$) were injected with maize oil intramuscularly (I/M), whereas the other four experimental groups $T_{2}$, $T_{3}$, $T_{4}$ and $T_{5}$ were given tamoxifen (I/M) dissolved in maize oil at the rate of 0.5 mg (0.5 TAM), 1.0 mg (1.0 TAM), 2.5 mg (2.5 TAM) and 5.0 mg (5.0 TAM)/kg body weight, respectively, up to 30 wks on every alternate day. At every 6-wk interval, blood samples were collected from nine birds of each treatment group for estimation of estrogen and progesterone. The same birds were sacrificed for determination of the weight of ovary, oviduct, liver and adipose tissue. There was no significant difference in egg production traits except onset of lay and egg number. Low doses of TAM ($T_{3}$) advanced the onset of egg laying by 15 days over the control. Tamoxifen influenced the hormonal profile (estrogen and progesterone) in a dose dependent manner. However, higher doses of TAM suppressed ovary and oviductal growth. From this study, it may be concluded that lower doses of TAM enhanced sexual maturity while higher doses suppressed ovary and oviductal growth.

• Imaging Science in Dentistry
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• 제40권1호
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• pp.9-14
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• 2010

Purpose : We evaluated the absorbed doses to the organs and calculated the effective doses when using the digital panoramic radiography. Materials and Methods : The absorbed dose averages in major organs of oral and maxillofacial region were measured using the Dental head phantom (CIRS Co., USA), $^nLi_2B_4O_7$ TLD chip and UD-716AGL dosimeter (Matsushita Electric Industrial Co., JPN) when performing indirect and direct digital panoramic radiography. Effective doses were calculated from correspond to ICRP 2007 recommendations for two panoramic radiography. Results : The absorbed dose average on indirect and direct digital panoramic radiography was highest in parotid glands as measured 1259.6 mGy and 680.7 mGy respectively. Absorbed dose average in another organs were high in order of esophagus, submandibular gland, tongue and thyroid gland on both types of digital panoramic radiography. The absorbed dose average was higher on indirect type than direct one (p<0.05). The effective dose was higher on indirect type than direct one as measured 13.28 mSv and 8.70 mSv respectively. Conclusion : The absorbed doses in salivary gland and oral mucosa were high. However, thyroid gland also demands the attention on radiography due to high tissue weighting factor in spite of the low absorbed dose.

• 대한치과의사협회지
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• 제52권3호
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• pp.153-163
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• 2014

3-dimensional information for anatomic stucture plays a role as integral part in clinical aspect of dental practice. CBCT(cone beam computed tomography) has been accepted as useful diagnostic tool offering Volume data and images for evaluating teeth and jaws in lower radiation dose than conventional CT. CBCT equipment is essential for the quality assurance of it to ensure continued satisfactory performance and result of adequate images. Dental practitioner and oral and maxillofacial radiologist should have a responsibility and critical thinking to deliver this technology to patients in a responsible way, so that diaganostic value is maximised and radiation doses kept as low as resonably achievable. CBCT imaging modality should be used only after a review of the patient's health and imaging history and the completion of a thorough clinical examination. Clinical guidelines are systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances Dental practitioners should prescribe CBCT imaging only when they expect that the diagnostic yield will benefit patient care, enhance patient safety or improve clinical outcomes significantly. Knowledge of patient dose is essential for clinicians who are making the decision regarding the justification of the exposure. There are some limitation in the measurement of patient dose in CBCT for the approval and adaptation of conventinal methodolgy in CT. It is also important to ensure that doses are optimised and in line with any national and international guidelines. The higher radiation doses of CBCT compared with conventional radiography, mean that high standards must be maintained. The Quality Assurance(QA) programme should entail surveys and checks that are performed according to a regular timetable. QA programme should be maintained by staff to ensure adherence to the programme and to raise its importance among staff.