• Title/Summary/Keyword: Animal studies

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MicroSPECT and MicroPET Imaging of Small Animals for Drug Development

  • Jang, Beom-Su
    • Toxicological Research
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    • v.29 no.1
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    • pp.1-6
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    • 2013
  • The process of drug discovery and development requires substantial resources and time. The drug industry has tried to reduce costs by conducting appropriate animal studies together with molecular biological and genetic analyses. Basic science research has been limited to in vitro studies of cellular processes and ex vivo tissue examination using suitable animal models of disease. However, in the past two decades new technologies have been developed that permit the imaging of live animals using radiotracer emission, X-rays, magnetic resonance signals, fluorescence, and bioluminescence. The main objective of this review is to provide an overview of small animal molecular imaging, with a focus on nuclear imaging (single photon emission computed tomography and positron emission tomography). These technologies permit visualization of toxicodynamics as well as toxicity to specific organs by directly monitoring drug accumulation and assessing physiological and/or molecular alterations. Nuclear imaging technology has great potential for improving the efficiency of the drug development process.

Differences and Similarity in Anxiety between Animal and Human (동물과 인간의 불안 : 차이와 공통점)

  • Chae Jeong-Ho
    • Anxiety and mood
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    • v.1 no.1
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    • pp.3-6
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    • 2005
  • Several contributing factors have been proposed for expression of excessive anxiety. Behavioral inhibition, activation of amygdala, and genetic vulnerability interchangeably affect each other. Only few studies have addressed the differences and similarities in anxiety between animal and human. The consensus is that individual vulnerability is a main factor for the expression of anxiety, although the interaction of environmental stressors and biological characteristics is involved in the presentation of anxiety. Further work is required to investigate how the interaction between stress and diathesis can affect responsiveness of stress and anxiety in animal and human. Here, the author reviews the findings regarding differences and similarities in both animal and human studies. Knowing the reciprocal relationship between the environment (stressors) and individual vulnerability or resilience, the proper understanding of anxiety and anxiety disorders would be possible.

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The Effect of Oral Administration at Herbal Medicines in Animal Models on Obesity: A Review of Animal Study Reports Published in Korea after 2010 (동물실험에서 한약제재 경구투여가 비만에 미치는 영향에 대한 국내 연구보고 고찰 - 2010년 이후 발표된 논문을 중심으로)

  • Kim, Jung-Min;Choi, Soo-Min;Yang, Doo-Hwa;An, Hee-Duk
    • Journal of Korean Medicine Rehabilitation
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    • v.27 no.3
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    • pp.13-32
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    • 2017
  • Objectives This study is to review the effect of herbal medicines on obesity in animal models reported in Korean domestic journals after 2010. Methods The Databases (Koreantk, KISS, NDSL) are searched with terms as obesity, and animal study reports on obesity with herbal medicines after 2010 were reviewed. Animal model, intervention, and obesity indicator were extracted. Results 69 articles were reviewed. 57 studies used high fat diet to induce obesity. 56 studies used complex herbal medicines. Most used herbal material for anti-obesity effect is Ephedrae Herba. Each study shows significant changes of obesity indicators. Conclusions These results suggest that herbal medicine is effective treatment to obesity. But we need continuously agonize and research more effective and safe herbal medicine.

Kisspeptin regulates the development of caprine primordial follicles in vitro

  • Magamage, Manjula Priyantha Sumith;Sathagopam, Sriravali;Avula, Kiran;Madushanka, Di Neththi Nimesh;Velmurugan, Sathya
    • Journal of Animal Reproduction and Biotechnology
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    • v.36 no.1
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    • pp.51-58
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    • 2021
  • Kisspeptin, a neuropeptide and the master controller of reproductive axis upstream to GnRH neurons, and its receptor are also expressed in extra-hypothalamic tissues, such as ovaries. As systemic kisspeptin has been shown to modulate follicular dynamics in cattle, we hypothesized that kisspeptin has direct actions on the ovarian follicular development. We also hypothesized that kisspeptin regulation of primordial follicle development is via modulation of VEGF expression. In order to test these hypotheses, we cultured caprine ovarian cortical strips in vitro for 7 days with supplementation of kisspeptin at 1, 10 and 100 µM concentration and observed the development of primordial follicles into intermediate, primary and secondary follicles. We also studied the alteration in the expression profile of VEGF and VEGF transcript variant 2 mRNA during follicular development in the presence of kisspeptin. We confirmed the presence of GPR54 in goat ovaries in our preliminary studies. Supplementation of kisspeptin at 1 and 10 µM concentration facilitated the development of primordial follicles into intermediate, primary and secondary follicles with less number of degenerated follicles while the same at 100 µM resulted in degeneration of follicles. We observed a drastic increase in the expression profile of VEGF and VEGF transcript variant 2 mRNA upon culture which was independent of kisspeptin treatment. In conclusion, our studies show that kisspeptin facilitates ovarian primordial development in vitro.

Suppressing breast cancer by exercise: consideration to animal models and exercise protocols

  • Lee, Jea Jun;Beak, Suji;Ahn, Sang Hyun;Moon, Byung Seok;Kim, Jisu;Lee, Kang Pa
    • Korean Journal of Exercise Nutrition
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    • v.24 no.2
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    • pp.22-29
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    • 2020
  • [Purpose] Exercise is thought to have a significant effect on chemotherapy, and previous studies have reported that exercise can increase patient survival. Thus, in this review, we aimed to summarize various animal models to analyze the effects of exercise on breast cancer. [Methods] We summarized types of breast cancer animal models from various reports and analyzed the effects of exercise on anti-cancer factors in breast cancer animal models. [Results] This review aimed to systematically investigate if exercise could aid in suppressing breast cancer. Our study includes (a) increase in survival rate through exercise; (b) the intensity of exercise should be consistent and increased; (c) a mechanism for inhibiting carcinogenesis through exercise; (d) effects of exercise on anti-cancer function. [Conclusion] This review suggested the necessity of a variety of animal models for preclinical studies prior to breast cancer clinical trials. It also provides evidence to support the view that exercise plays an important role in the prevention or treatment of breast cancer by influencing anticancer factors.

Experimental Animal Models of Coronavirus Infections: Strengths and Limitations

  • Mark Anthony B. Casel;Rare G. Rollon;Young Ki Choi
    • IMMUNE NETWORK
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    • v.21 no.2
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    • pp.12.1-12.17
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    • 2021
  • Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Since the emergence of SARS-CoV-2 in the human population in late 2019, it has spread on an unprecedented scale worldwide leading to the first coronavirus pandemic. SARS-CoV-2 infection results in a wide range of clinical manifestations from asymptomatic to fatal cases. Although intensive research has been undertaken to increase understanding of the complex biology of SARS-CoV-2 infection, the detailed mechanisms underpinning the severe pathogenesis and interactions between the virus and the host immune response are not well understood. Thus, the development of appropriate animal models that recapitulate human clinical manifestations and immune responses against SARS-CoV-2 is crucial. Although many animal models are currently available for the study of SARS-CoV-2 infection, each has distinct advantages and disadvantages, and some models show variable results between and within species. Thus, we aim to discuss the different animal models, including mice, hamsters, ferrets, and non-human primates, employed for SARS-CoV-2 infection studies and outline their individual strengths and limitations for use in studies aimed at increasing understanding of coronavirus pathogenesis. Moreover, a significant advantage of these animal models is that they can be tailored, providing unique options specific to the scientific goals of each researcher.

Review of Database Configuration of Manure Characteristics, Analysis Methods, Bio-methane Potential Test for High Solid Manure Recycling (고상 가축 분뇨 자원화를 위한 데이터베이스 구성에 따른 분뇨특성, 분석방법 및 바이오가스 평가 방법에 대한 고찰)

  • Choi, Yong-Jun;Lee, Sang-Rak
    • Journal of Animal Environmental Science
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    • v.21 no.1
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    • pp.9-20
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    • 2015
  • The livestock manure recycling have been performed worldwide because of its environmental and economic benefits. However, domestic standard protocol was nothing for high solid manure. Therefore, This paper was conducted to review database configuration of manure characteristics, analysis methods, bio-methane potential test for high solid manure recycling. In American society of agricultural engineers standard, manure characteristics indicated about sort of thirty types. This is important information to determine for manure recycling method. Furthermore, in order to determine exact manure characteristics recommended that synchronized chemical analysis method among studies. Bio-methane potential tests are widely performed in studies about estimation of organic substrates methane production. Although various methods and parameters were used, was no standard protocol and guideline in domestic. Bio-methane potential test methods and parameters were reviewed through various researches. Consequently, this paper is expected that assist to additional studies and manure characteristic database.

Preliminary Study on the Use of Bacillus sp., Vibrio sp. and Egg White to Enhance Growth, Survival Rate and Resistance of Penaeus monodon Fabricius to White Spot Syndrome Virus

  • Yusoff, F.M.;Shariff, M.;Lee, Y.K.;Banerjee, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.10
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    • pp.1477-1482
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    • 2001
  • Research in low cost feeds with high nutritional value and immunogenicity is important to reduce production cost and increase yields in the shrimp industry. In this study, immunostimulants of bacterial origin (peptidoglycan and lipopolysaccharides) and egg white were incorporated in shrimp diets as feed additives to determine the growth, survival and tolerance of Penaeus monodon to white spot syndrome virus (WSSV). Although the results obtained were not statistically significant (p>0.05) among the treatments, shrimp fed with bacterial additives and egg white showed higher weight gain, specific growth rate and survival than those fed on commercial shrimp diet. Shrimp fed with artificial diet showed 100% mortality when challenged with WSSV. However, shrimp fed on peptidoglycan supplemented diet had higher survival than their counterpart, whereas shrimp fed on egg white supplemented diet had a higher specific growth rate and better tolerance when challenged with WSSV. Further studies are required to determine the effectiveness and optimization of bacterial strains and egg white as feed additives to increase production and enhance the shrimp immune response to diseases.

Effects of dietary fiber in gestating sow diets - A review

  • Hyunwoong Jo;Beob Gyun Kim
    • Animal Bioscience
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    • v.36 no.11
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    • pp.1619-1631
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    • 2023
  • The objective of this review was to provide an overview of the effects of dietary fiber (DF) on reproductive performance in gestating sows. Dietary fibers have been suggested to modulate microbiota in the intestine and the immune system of gestating sows and to improve gut health. Thus, DF may help alleviate the adverse effects of the stressful production cycle of gestating sows. These benefits may subsequently result in improved reproductive performance of sows. Previous studies have reported changes in microbiota by providing gestating sows with DF, and the responses of microbiota varied depending on the source of DF. The responses by providing DF to gestating sows were inconsistent for antioxidative capacity, hormonal response, and inflammatory response among the studies. The effects of DF on reproductive performance were also inconsistent among the previous studies. Potential reasons contributing to these inconsistent results would include variability in reproductive performance data, insufficient replication, influence of other nutrients contained in the DF diets, characteristics of DF, and experimental periods. The present meta-analysis suggests that increasing the total DF concentration by 10 percentage units (e.g., 12% to 22% as-fed basis) in gestating sow diets compared to the control group improves the litter born alive by 0.49 pigs per litter. However, based on the present review, questions remain regarding the benefits of fibers in gestating sow diets. Further research is warranted to clarify the mode of action of fibers and the association with subsequent reproductive performance in gestating sows.

Validation of Methods for Isolation and Culture of Alpaca Melanocytes: A Novel Tool for In vitro Studies of Mechanisms Controlling Coat Color

  • Bai, Rui;Sen, Aritro;Yu, Zhihui;Yang, Gang;Wang, Haidong;Fan, Ruiwen;Lv, Lihua;Lee, Kyung-Bon;Smith, George W;Dong, Changsheng
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.4
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    • pp.430-436
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    • 2010
  • The objective of the present studies was to develop and validate a system for isolation, purification and extended culture of pigment-producing cells in alpaca skin (melanocytes) responsible for coat color and to determine the effect of alpha melanocyte stimulating hormone treatment on mRNA expression for the melanocortin 1 receptor, a key gene involved in coat color regulation in other species. Skin punch biopsies were harvested from the dorsal region of 1-3 yr old alpacas and three different enzyme digestion methods were evaluated for effects on yield of viable cells and attachment in vitro. Greatest cell yields and attachment were obtained following dispersion with dispase II relative to trypsin and trypsin-EDTA treatment. Culture of cells in medium supplemented with basic fibroblast growth factor, bovine pituitary extract, hydrocortisone, insulin, 12-O-tetradecanolphorbol-13-acetate and cholera toxin yielded highly pure populations of melanocytes by passage 3 as confirmed by detection of tyrosinase activity and immunocytochemical localization of melanocyte markers including tyrosinase, S-100 and micropthalmia-associated transcription factor. Abundance of mRNA for tyrosinase, a key enzyme in melanocyte pigment production, was maintained through 10 passages showing preservation of melanocyte phenotypic characteristics with extended culture. To determine hormonal responsiveness of cultured melanocytes and investigate regulation of melanocortin 1 receptor expression, cultured melanocytes were treated with increasing concentrations of ${\alpha}$-melanocyte stimulating hormone. Treatment with ${\alpha}$-melanocyte stimulating hormone increased melanocortin receptor 1 mRNA in a dose dependent fashion. The results demonstrated culture of pure populations of alpaca melanocytes to 10 passages and illustrate the potential utility of such cells for studies of intrinsic and extrinsic regulation of genes controlling pigmentation and coat color in fiber-producing species.