• Title/Summary/Keyword: Experimental animals

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CB6F1-Tg rasH2 Mouse Carrying Human Prototype c-Ha-ras Gene As an Alternative Model For Carcinogenicity Testing For Pharmaceuticals

  • Usui, T.;Urano, K.;Suzuki, S.;Hioki, K.;Maruyama, Ch.;Tomisawa, M.;Ohnishi, Y.;Suemizu, H.;Yamamoto, S.
    • Toxicological Research
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    • v.17
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    • pp.293-297
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    • 2001
  • The international pharmaceutical and regulatory communities had been recognizing the limited utility of conventional rodent carcinogenicity study particularly on the second species, mouse, after intense investigation of carcinogenicity data base worldwide, and a new scheme for carcinogenicity testing for pharmaceuticals was proposed at the Expert Working Group on Safety in the International Conference on Harmonization (ICH) in 1996. CB6F 1-Tg rasH2 mouse carrying human prototype c-Ha-ras gene with its own promoter/enhancer is one oj the new carcinogenicity assay model for human cancer risk assessment. Studies have been conducted since 1992 to validate the transgenic (Tg) mice for rapid carcinogenicity test-ing, short term (26 weeks) studies with genotoxic (by Salmonella), non-genotoxic carcinogens, genotoxic non-carcinogens, non-genotoxic non-carcinogens revealed relatively high concordance oj the response of the Tg mouse with classical bioassay across classes of carcinogenic agents. Mechanistic basis for carcinogensis in the model are being elucidated in terms of the role of overexpression and/or point mutation of the transgene. This report review the initial studies of validation of the model and preliminary results of on-going ILSI HESI ACT project will be presented.

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Social Isolation Selectively Increases Anxiety in Mice without Affecting Depression-like Behavior

  • Kwak, Chul-Jung;Lee, Sue-Hyun;Kaang, Bong-Kiun
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.5
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    • pp.357-360
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    • 2009
  • It is hypothesized that a number of environmental factors affect animals' behavior. Without controlling these variables, it is very hard for researchers to get not only reliable, but replicable data from various behavioral experiments testing animals' cognitive as well as emotional functions. For example, laboratory mice which had restricted environment showed different synaptic potentiation properties with wild mice (Zhao MG et al., 2009). While performing behavioral experiments, however, it is sometimes inevitable that the researcher changes the animals' environments, as by switching the cages in which experimental animals are housed and separating animals raised together into small experimental groups. In this study, we investigated the effect of environmental changes on mice's emotional behaviors by socially isolating them or reducing the size of their cage. We found that social isolation selectively increases the animals' levels of anxiety, while leaving depression-like behaviors unchanged. On the other hand, alteration of the housing dimensions affected neither their anxiety levels nor their depression-like behaviors. These results suggest that environmental variables may have a prominent impact on experimental animals' emotional behaviors and possibly their psychological states, leading to bias in the behavioral data produced from experiments.

Changes in Plasma Lipid Pattern in Streptozotocin-Induced Diabetic Rats: A Time Course Study (스트렙토토신-당뇨쥐의 유병기간에 따른 혈중지질패턴의 경시적 변화)

  • 이수자
    • Journal of Nutrition and Health
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    • v.32 no.7
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    • pp.767-774
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    • 1999
  • This study was carrid out to examine a part of the mechanism for the etiology of diabetic complications. Thirty normal and forty streptozotocin(STZ)-induced diabetic rats were used as the animal models. Animals were sacrificed at the time points of 3 days, 1, 2, 4 and 6 weeks after STZ-injection and time course in body weight and organ weight, the levels of blood glucose, plasma lipid patterns, and atherogenic index were measured during 6 weeks. The STZ-diabetic animals showed 63% survival rate and fsting blood glucose levels of the diabetic animals measured in the range of 230-410mg/dL during the experimental period. The body weigh of diabetic animals decreased significantly throughout the experimental period and the relative weights of organs to body weight were significantly higher than the normal control ones. The enlargement of the kidney in the diabetic animals was especially remarkable. Plasma triglyceride concentration in diabetic rats substancially increased from the first week of onset of diabetes mellitus and maintained higher levels than the control ones throughout the whole experimental period. The plasma total cholesterol level and atherogenic index in the diabetic rats were significantly higher than the normal ones from the third day after STZ injection and showed a gradual increase with the duration of the disease. Throughout the experiment, the diabetic rats consistently showed a slightly lower HDL-cholesterol level compared to the normal animals. From the results of this study, it appears that the significant changes in blood lipid pattern in STZ-diabetic animals start from the first week after STZ injection.

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A Survey on the Laboratory Animals in Korea (우리나라 실험동물 실태에 관한 조사)

  • Kim, Jae-Yeon
    • Journal of environmental and Sanitary engineering
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    • v.4 no.2 s.7
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    • pp.33-45
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    • 1989
  • The survey was conducted on the actual conditions of species, the facilities, a establishment of regulation concerning laboratory animals and the related problems on users and suppliers of laboratory animals in Korea. The questionnaires were sent to 430 and received from 107$(24.9\%)$ places. The results obtained were as follows : 1. Experimental animals used at the 107 places were 21 species: mouse(90\;places,\;84.1\%)$, rat $(61,\;57.0\%)$, rabbit$(76,\;71.0\%)$, guineapig$(42,\; 39.3\%)$ etc. 2. The main organizations using laboratory animals were university $46(43.0\%)$, institute $32(29.9\%)$ and pharmaceutical company $27(25.2\%)$ etc. 3. Most the laboratory animal facilities in Korea have been conventional system without environmental controls, but a few places have been recently established barrier system. 4. To get a good experimental result, a regular genetic and microbiological monitoring of laboratory animals should be done. 5. It was required that a educational facilities and a quality test agency for laboratory animals should be established. 6. It was also required that a regulation for breeding and using of laboratory animals should 'be enacted.

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Swimming Performance of Aquatic-animals and Their Morphological Adaptation (수중동물의 헤엄침 성능과 형태학적 적응)

  • Sohn, Myong-Hwan;Lee, Seung-Hee;Han, Cheol-Heui
    • Journal of the Korea Institute of Military Science and Technology
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    • v.12 no.6
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    • pp.796-807
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    • 2009
  • The swimming abilities of aquatic-animals are of vital importance to their ecology. The relationship between outer shapes and the swimming ability has been focused just a few centuries ago by engineering community. Present paper surveys the recent studies of the aquatic-animals' swimming performance in the morphological point of view. Also an experimental study is performed in order to investigate the effect of the tail fin's shape on the propulsive performance. The result showed that the morphological study provided valuable data for exploring the secrets of the aquatic-animals' swimming performance.

Effects of repeated tuberculin skin testings on immune responses in experimental monkeys

  • Min, Fangui;Wang, Jing;Yuan, Wen;Kuang, Huiwen;Zhao, Weibo
    • Journal of Animal Science and Technology
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    • v.56 no.8
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    • pp.32.1-32.4
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    • 2014
  • Though many alternative methods to tuberculin skin testing (TST) have been established and evaluated in recent years, sensitivities and specificities of most methods could not meet the requirements of golden standards. In this study, we sought to identify whether repeated TSTs could affect the immune responses in experimental monkeys. Nine natural tuberculosis (TB) monkeys receiving repeated TSTs biweekly were used to demonstrate the effect on TST responsiveness. Two healthy monkeys were administrated with repeated TSTs to analyze the immune response profiling. Intrapalpebral reactions in TB infections gradually weakened or presented intermittent positive reactions. The leukocyte counts, cytokine responses, and antibody responses to all antigens except Old tuberculin (OT) and MPT64L showed no specific changes for TB in healthy monkeys. Positive antibody responses to OT and MPT64L emerged during the first half experimental period, which may cause by their cross-reactivity with mycobacterial species. Results showed that repeated TSTs had no significant effects on immune responses in healthy monkeys but a progressive reduction in TST responsiveness in TB infections.

The Change of Soil Animals by Forest Ecosystem Restoration Types (산림생태계 복원유형별 토양동물 변화)

  • Kang, Hyun-Mi;Song, Jae-Tak;Choi, Song-Hyun;Kim, Dong-Hyo
    • Korean Journal of Environment and Ecology
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    • v.31 no.1
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    • pp.62-71
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    • 2017
  • In this study, in order to examine the change of soil animals by vegetation restoration types, experimental sites with biotope restoration method, forest topsoil paving method, small diameter trees planting method and multi-layer community planting method were applied and the control site was selected. The naturalness of soil animals was analysed by studying the change of soil animals. It was confirmed that the control site has a high level of the naturalness of soil animals as it includes a mixture of fauna sensitive and insensitive to environment distributed widely over the site. The experimental site with biotope restoration method showed a similar level of the naturalness of soil animals as the control site. Furthermore, the naturalness of soil animals in the experimental sites with small diameter trees planting method and multi-layer community planting method also showed a progressive restoration although the level of the naturalness of soil animals is lower than the experimental site with the biotope restoration method. Therefore, it is confirmed that the experimental site with biotope restoration method shows a faster recovery of soil animal than other sites. This is because this method uses the portion of topsoil and subsoil that were dug from the intact forest during transplantation.

Pathological Studies on Experimental Poisoning of Organic Phosphate Insecticide (유기인제 중독에 관한 병리학적 연구)

  • Lee, Cha Soo;Lim, Chang Hyeong
    • Korean Journal of Veterinary Research
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    • v.15 no.1
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    • pp.39-45
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    • 1975
  • The authors believe that farm livestok will be greatly affected by the marked increasing use of organic phosphate. This study was carried out to observe the clinical signs and histopathological changes of mouse, guinea pig, hamster and rabbit that were orally administered with diazinon used usually as agricultural insecticide, and cholinesterase (ChE) activity was histochemically examined in the liver, heart, kidney, adrenal gland, duodenum and salivary gland of these experimental animals administered with diazinon. The results obtained were as follows: 1. Clinical signs such as dullness, severe salivation, ataxia, dyspnea, irregular slight convulsion and inappetance and as the histopathological changes cloudy swelling, congestion and hemorrhage of parenchymal organs, catarrh or local necrsois of the gastrointestinal tract, congestion or hemorrhage of the other organs were observed. Especially, hemorrhage of adrenal glands (rabbit, guinea pig) and pulmonary congestion and hemorrhage were necessarily constant. 2. In the histochemical study, ChE activity appeared intensely in the liver, heart, medulla of adrenal glands and salivary glands (submaxillary and parotid) of control animals, but ChE activity was negative or markedly decreased in experimental animals administered with diazinon. There was no marked difference between the control and experimental animals in ChE activity of the kidney. 3. Histochemical observation of ChE activity was helpful to explain the clinical signs and histopathological changes and was regarded as a diagnostic method for organic phosphate poisoning.

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Studies on Piroplasmosis Infection and Morphological Development of Piroplasma in Experimental Animals (피로풀라스마병(病)에 관(關)한 연구(硏究) 실험동물(實驗動物)에 대(對)한 감염시험(感染試驗) 및 그 형태학적(形態學的) 변화(變化)에 대(對)하여)

  • Han, T.W.
    • Korean Journal of Veterinary Research
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    • v.8 no.2
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    • pp.98-109
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    • 1968
  • The small type piroplasma which is known to be prevailing in Korean cattle was injected to un-susceptible hosts such as mice, guinea pigs, rats, rabbits, fowls and developing chicken eggs by i.v., i.p, and intra C.A.M. routes, and its morphological development in each animal species was observed. 1. The small type piroplasma of cattle did not produce any pathogenicity in the experimental animals such as mice, guinea pigs, rats, rabbits, fowls and developing chicken embryos. However, only a partial sign for developing cycle of the organism was observed in the peritoneal fluid. The schizogony of protozoa was not detected in any organs of the inoculated animals. 2. In the animals inoculated, the parasites of I-III types, relative to the process of time in the host, have changed their shapes into IV-VI types and then VI-X types however, the type X was not restored to the type I. In guinea pigs, more grape type was detected then X type in number, and in process of time, the shape was changed from round to elliptic, and the pointed end of the organism appeared in flesh color. 3. None of the organisms were found from the blood stream of inoculated animals excepts only a few piroplasma as were found in the experimental mice shortly after inoculation or i.v. route, No protozoa was also found in the organs of the animals autopsied. 4. The form change of protozoa was more clear in these animals than that in susceptible host. The most piroplasmas have changed their forms into VI-X types 30 hours after inoculation and were dispersed from R.B.C. Tracing of piroplasrna beyond this stage was not attempted. 5. The small type piroplasma comprises in I. X types and it is further believed that VII-X types which were freed from one cell proceeded to invade others. The from of development resembles to the small type of piroplasma which is prevailing in Japan.

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Animal Experiments Using Rotator Cuff

  • Chung, Seok Won;Kim, Sae Hoon;Oh, Joo Han
    • Clinics in Shoulder and Elbow
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    • v.17 no.2
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    • pp.84-90
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    • 2014
  • In conducting animal studies using rotator cuff, researchers should select the appropriate types of animals and experimental models. This should also be followed by complete understanding of the selected experimental animals as well as the methods for evaluating the results. Thus, researchers could minimize errors and failure in conducting animal experimental studies. Further, this will provide a basis of establishing new idea and theory about rotator cuff diseases.