• IMMUNE NETWORK
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• 제2권3호
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• pp.150-157
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• 2002

Background: Although Tat plays a role as a potent transactivator in the viral gene expression from the Human Immunodeficiency Virus type 1 long terminal repeat (HIV-1 LTR), it does not function efficiently in rodent cells implying the absence of a human specific factor essential for Tat-medicated transactivation in rodent cells. In previous experiments, we demonstrated that one of chimeric forms of TAR (transacting responsive element) of HIV-1 LTR compensated the restriction in rodent cells. Methods: To characterize the nature of the compensation, we tested the effects of several upstream binding factors of HIV-1 LTR by simple substitution, and also examined the role of the configuration of the upstream binding factor(s) indirectly by constructing spacing mutants that contained insertions between Sp1 and TATA box on Tat-mediated transactivation. Results: Human Sp1 had no effect whereas its associated factors displayed differential effects in human and rodent cells. In addition, none of the spacing mutants tested overcame the restriction in rodent cells. Rather, when the secondary structure of the chimeric HIV-1 TAR construct was destroyed, the compensation in rodent cells was disappeared. Interestingly, the proper interaction between Sp1 and TATA box binding proteins, which is essential for Tat-dependent transcription, was dispensable in rodent cells. Conclusion: This result suggests that the human-specific Tat cofactor acts to allow Tat to interact effectively in a ribonucleoprotein complex that includes Tat, cellular factors, and TAR RNA, rather than be associated with the HIV-1 LTR upstream DNA binding factors.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1994년도 교수 연수회(환경)
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• pp.431-438
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• 1994

As currently conducted, standard rodent bioassays do not provide sufficient information to assess carcinogenic risk to humans at doses thousands of times below the maximum tolerated dose. Recent analyses indicate that measures of carcinogenic potency from these tests are restricted to a narrow range about the maximum tolerated dose and that information on shape of the dose-response is limited in experiments with only two doses and a control. Extrapolation from high to low doses should be based on an understanding of the mechanisms of carcinogenesis. We have postulated that administration of the maximum tolerated dose can increase mitogenesis which, in turn. increases rates of mutagenesis and, thus, carcinogenesis. The animal data are consistent with this mechanism, because about half of all chemicals tested are indeed rodent carcinogens, and about 40% of the positives are not detectably mutagenic. Thus, at low doses where cell killing does not occur, the hazards to humans of rodent carcinogens may be much lower than commonly assumed. In contrast, for high-dose exposures in the workplace, assessment of hazard requires comparatively little extrapolation. Nevertheless. permitted workplace exposures are sometimes close to the tumorigenic dose-rate in animal tests. Regulatory policy to prevent human cancer has primarily addressed synthetic chemicals, yet similar proportions of natural chemicals and synthetic chemicals test positive in rodent studies as expected from an understanding of toxicological defenses, and the vast proportion of human exposures are to natural chemicals. Thus, human exposures to rodent carcinogens are common. The natural chemicals are the control to evaluate regulatory strategies, and the possible hazards from synthetic chemicals should be compared to the possible hazards from natural chemicals. Qualitative extrapolation of the carcinogenic response between species has been investigated by comparing two closely related species: rats and mice. Overall predictive values provide moderate confidence in interspecies extrapolation; however, knowing that a chemical is positive at any site in one species gives only about a 50% chance that it will be positive at the same site in the other species.

• 한국기계가공학회지
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• 제15권4호
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• pp.30-39
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• 2016

There have been many cases of deaths from crushing caused by dense crowds. Numerous studies about pedestrian flow have performed various simulations, but the experimental data to prove the simulations are still not enough. In this paper, the evacuation of pedestrians for proving pedestrian flow simulation is observed. Due to the possibility of real casualties, it is difficult to experiment with humans directly. Therefore, ten C57BL/6NCrSIc mice have been used. It is assumed that C57BL/6NCrSIc mice act like humans in panic situations. Electrical Stimulus Experiments on mice are conducted for exits with various angles. ICY software is applied in this paper. As a result, the mice escape fast at a proper angle of 45 to 60 degrees.

• 한국환경성돌연변이발암원학회지
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• 제19권1호
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• pp.39-45
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• 1999

Human Carcinogenic Potency (HCP) can be estimated based on human daily exposure dose to carcinogen (Dh), body weight (Wh), 10% tumorigenic dose (TD10), and slope factor at TD10 (Q10) from 2-yr bioassay data. This approach is more relevant to humans generally exposed to low doses of carcinogens and can reduce more of extrapolation errors from high dose in animal experiments to low dose in humans than HERP (human exposure dose/rodent potency dose) proposed by Ames et al. (Science, 236, 271-280, 1987). TD50 and HERP have been routinely used to compare rodent carcinogenic potency and human carcinogenic potency, but those approaches have had limitations in extrapolation of high dose to low dose in humans. The advantages of HCP are to estimate human exposure dose (Dh) by human monitoring instead of environmental monitoring, to consider slope factor (Q10) which reflects the tendency of curve at low dose, and to use TD10 which represents much lower dose thant TD50 or HERP. HCP will be a useful parameter for the estimation of human carcinogenic potency in risk assessment and management of carcinogens.

• 한국기계가공학회지
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• 제20권3호
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• pp.8-15
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• 2021

Despite advances in technology, crushing accidents still occur during emergency evacuations of crowded public spaces. To prevent crushing accidents, it is necessary to understand the flow of pedestrians during evacuation scenarios through experiments. Since experiments with humans can generate real accidents, we performed experiments on rodents to approximate human behavior. To trigger an emergency evacuation response, we applied electrical stimulation to the feet of the rodents. Although electrical stimulation has been applied to mice in many experiments, studies on the intensity and pattern of electric stimulation required to evoke a rapid evacuation response in mice is still lacking. In this study, we experimentally investigated how the evacuation flow of mice changes according to the amplitude, event, and duration of electric stimulation.

• Journal of Korean Neurosurgical Society
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• 제61권5호
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• pp.539-547
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• 2018

Traumatic spinal cord injury (SCI) research has recently focused on the use of rat and mouse models for in vivo SCI experiments. Such small rodent SCI models are invaluable for the field, and much has been discovered about the biologic and physiologic aspects of SCI from these models. It has been difficult, however, to reproduce the efficacy of treatments found to produce neurologic benefits in rodent SCI models when these treatments are tested in human clinical trials. A large animal model may have advantages for translational research where anatomical, physiological, or genetic similarities to humans may be more relevant for pre-clinically evaluating novel therapies. Here, we review the work carried out at the University of British Columbia (UBC) on a large animal model of SCI that utilizes Yucatan miniature pigs. The UBC porcine model of SCI may be a useful intermediary in the pre-clinical testing of novel pharmacological treatments, cell-based therapies, and the "bedside back to bench" translation of human clinical observations, which require preclinical testing in an applicable animal model.

• 한국임상수의학회지
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• 제27권6호
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• pp.663-667
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• 2010

본 연구는 설치모델 동물에서 봉독의 항통각 효과를 평가하고, 한국산 봉독과 미국산 봉독의 항통각 효과를 비교하는 것이 주된 관심이다. 한국산 봉독은 특별히 고안된 봉독 추출기를 사용하여 일벌 (Apis mellifera L.)에 전기충격을 가하여 생봉독을 수집하였으며, 수집된 생봉독은 봉독 건조기를 이용하여 봉독을 건조하였다. 미국산 봉독은 미국 시그마회사에서 상업적으로 판매되는 건조 봉독을 이용하였다. 한국산 봉독과 미국산 건조봉독을 생리식염수에 희석하여 체중 kg당 6 mg과 0.6 mg, 0.06 mg을 마우스와 랫드에 피하로 투여하여 항진통 효과를 조사하였다. 항통각 효과는 한국산 봉독과 미국산 봉독은 서로 비슷하였으며, 봉독의 용량이 많을수록 항통각 효과가 크게 나타났다. 이상의 결과에서 한국산 건조 봉독은 통증 치료에 사용될 수 있을 것으로 생각된다.

• 한국가축번식학회지
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• 제26권4호
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• pp.321-328
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• 2002

The hormone resistin is associated with type II diabetes mellitus in rodent model. Resistin impairs glucose tolerance and insulin action. A new class of anti-diabetic drugs were called thiazolidinediones (TZDs) downreguates a resistin. Resistin gene expression is induced during adipocyte differentiation and resistin polypeptide is secreted by adipocytes. But, the correlation between increased adiposity and resistin remains unknown. The objectives of this study was to clone a mouse resistin CDNA and to generate transgenic mice overexpressing mouse resistin gene. The pCMV-mus/resistin gene was prepared from previous recombinant pTargeT$^{TM}$-mus/resistin by digestion of Bgl II, and has used for microin- jection into pronuclei of one cell embryos. Mouse resistin expression was detected in transgenic F$_1$mice by RT-PCR. The transgenic mouse with resistin gene expression has heavier body weight which was measured higher level of plasma glucose than that of normal mouse. And in diet-induced experiments, in fasting group, resistin expression was higher than that of re-feeding group. This result demonstrates that the resistin gene overexpressing mice may be became to obesity and be useful as an animal disease model to be diabetes caused by insulin resistance of resistin.n.

• 셀메드
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• 제5권1호
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• pp.6.1-6.10
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• 2015

Fumaria indica Linn. (Syn: Fumaria parviflora, Fumariaceae) is a wildly grown weed, mentioned and recommended in classical Ayurvedic texts for treatments of variety of ailments including dermatological diseases, topical diseases, cardiovascular complaints, circulatory disease, fever and headache etc. The present pilot study was designed to experimentally verify the possibility that fumarates are the major bioactive principles of Fumaria indica extracts involved in their stress response modulating activities, and to estimate pharmacologicallyactive dose ranges of fumarates and standardized methanolic extract of Fumaria indica (MFI). Effect of single, 5 and 10 daily oral doses of pure fumaric acid (FA), monomethyl fumarate (MMF), dimethyl fumarate (DMF) and MFI was quantified in well validated rodent models viz. apomorphine induced cage climbing, stress induced hyperthermia, and elevated plus-maze tests. Obtained results reveal high efficacy of MFI and pure fumarates possess qualitatively analogous activity profiles in all the three tests. There were no significant difference in the potencies of pure FA, MMF and DMF in the three tests, whereas efficacy of MFI in the elevated plus maze test for anxiolytics was higher than in the other two tests. Efficacies of all the four test agents in all the three tests increased with increasing number of days of oral treatments. Results of these pilot experiments should be helpful for more rational selections of pharmacologically interesting dose ranges and treatment regimens of fumarates and Fumaria indica extracts for further more holistic explorations of their diverse therapeutic potentials.

• 복식
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• 제57권3호
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• pp.14-22
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• 2007

This study is about the excavated costume representing fundamental "Conservation and Restoration". It's not a report of a specific case, but it is a guideline that contains the costume and textile of museum collection. It is not research based on experiments; however, this paper is basically consists of various reported-documents. Followings are the conclusions of this study 1. These are the factors that we have to know to prevent the causes of fabric's degradation. -Light, -Humidity and temperature, -Microscopic organism, -Insect and rodent animal, -Air pollution, -Ph, -Handling 2. Basic principles of conservation and restoration follows are: -Select the Reversible method, -Represent the easily distinguishable repaired place, -Should be acted by an expert or people with experience, -Before the restoration, accurate and specified records should be completed, -Procedure, treatment method, and materials used should be recorded prior to restoration, -Should be cared minimally, -Be cautious when using the conservation materials, -When caring, make sure nothing is against the principle of aesthetic, historic, and form of preservation 3. The types of restoration are type of straight or curve, type of hole, type of without warp or weft, type of special part damage something like sleeve, collar, type of form that is severely damaged, and type of separated pieces. 4. The method of restoration is sewing, stitching, and the combination of sewing and stitching. 5. The restoration seams are welt seam, plain seam, flat felled seam, french seam etc. And there are kinds of used-sewing, such as, broad stitching, backstitch, half backstitch, basking, hemming, saddle stitching etc.