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The Status of Laboratory Animal Production and Visions in the 21st Century - Review -

  • Gartner, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.7
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    • pp.1142-1151
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    • 1999
  • Today, laboratory animal production has decreased world-wide to half the number estimated in 1970 of more than 100 Mio. This is due to the cell-biological assays which replaced animal experimentation as a first allround method to solve biomedical problems. Animal experimentation remains the most significant experimental method for the study of higher organized physiological systems and their multifactorial connections. This requires maximal uniformity of all quantitative traits among the animals used for such studies (mainly mice and rats) and stability of these traits for reproducing such studies at any time world-wide. The success of the developed methods for the standardization of laboratory animals was analyzed and were found only partly be acceptable. Getting a higher degree of uniformity among standardized inbred animals is blocked by "intangible variance". This is caused by influences of ooplasm, shown by experimental twin and clone studies. Manipulation of this component of variance is essential in the future. - Genetic drifts impair the necessary stability of biological traits. There are a few disadvantages associated with the cryopreservation of embryos and other methods are required. - Dogs and cats were replaced by pigs as laboratory animals. A new line of animal production will evolve over the next 25 years with similarities to the present laboratory animal production, because in future pigs were used as donors for xenotransplants for men.

Effect of Rhizoma gastrodiae on glucose oxydase induced neurotoxicity in cultured mouse spinal dorsal root ganglion neurons

  • Park, Seung-Taeck;Park, Yang-Kyu;Park, Jae-Hwang;Cho, Kwang-Ho;Ryu, Do-Gon;Jeon, Byung-Hoon;Shin, Min-Kyo;Han, Du-Seok;Cho, Nam-Su;Shin, Dong-Min
    • Advances in Traditional Medicine
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    • v.1 no.1
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    • pp.64-70
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    • 2000
  • Effects of Rhizoma gastrodiae on glucose oxidase-induced neurotoxicity was investigated in cultured newborn mouse spinal dorsal root ganglion(DRG) neurons that were treated in the media with or without glucose oxidase. In addition, the protective effect of Rhizoma gastrodiae extract against glucose oxidase-induced neurotoxicity was examined. Cytotoxic values were expressed as a percentage of number of living cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. In this paper, exposure of neurons to glucose oxidase resulted in a significant call death in a dose- and time-dependent manners in DRG neuron cultures. The decrease in cell viability induced by the glucose oxidase was blocked by Rhizoma gastrodiae extract. These results indicate that the neuroprotective effect of Rhizoma gastrodiae extract against glucose oxidase-induced neurotoxicity may result from a prevention or attenuation of oxidative damage induced by glucose oxidase.

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The Effect of Poria cocos Extract to Inhibit Enterovirus Replication (적복령 추출물의 심근염 유발 엔테로바이러스 증식 억제 효과)

  • Han, Jae-Young;Kim, Jin Hee;Lim, Byung-Kwan
    • Korean Journal of Pharmacognosy
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    • v.47 no.2
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    • pp.137-142
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    • 2016
  • Enterovirus is a common cause of several severe diseases such as myocarditis, hand-foot-mouth disease, and meningitis in children and adult. There are many try to develop new antiviral drug for direct treatment in virus infection. However, synthetic chemical antiviral drug is not working. To overcome this limitation, we examined plant extracts. The antiviral effect of plant extracts was screened by HeLa cell survival assay in coxsackievirus B3 (CVB3) infection. We observed a strong antiviral effect of Poria cocos extract in a dose-dependent manner (1 mg/ml~0.01 mg/ml). P. cocos extract (1 mg/ml) treatment was dramatically decreased virus protease 2A induced eIF4G-I cleavage and virus capsid protein VP1 production. CVB3 positive and negative strand RNA amplification were significantly reduced in P. cocos extract treatment. P. cocos extract completely blocked early time activation of ERK and AKT activity in CVB3 infection. Taken together these data indicate that the treatment of P. cocos extract strongly inhibit CVB3 replication. Poria cocos extract may possible to developed as a therapeutic agent for enterovirus.

Control of Parturition Time on Pig II. Effect of Sympathetic Nerve and Adrenergic Agonist on Uterine Smooth Muscle Motility (돼지 분만 시기의 조절에 관하여 II. 자궁 평활근의 운동성에 대한 교감신경과 Adrenergic Agonist의 영향)

  • 심철수;이양성;임종옥
    • Korean Journal of Veterinary Service
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    • v.17 no.3
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    • pp.255-263
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    • 1994
  • To elucidate the action of the adrenergic nerve on the isolated uterine smooth muscle of the pig, effects of electrical transmural nerve stimulation and norepinephrine were investigated on the pretreatment of phentolamine ; non-selective ${\alpha}$-adrenoceptor blocker, propranolol ; ${\beta}$-adrenoceptor blocker and the yohimbine;${\alpha}_2$-selective adrenoceptor blocker from physiograph. 1. The relaxation response induced by norepinephrine was the concentration of $10^{-6}$ M at first and maximum response was concentration of $10^{-4}$M. 2. The relaxation response induced by norepinephrine was not effected by the pretreatment with non-selective $\alpha$-adrenoceptor blocker, phentolanune ($10^{-6}$ M) but was completely blocked by the pretreatment with ${\beta}$-adrenoceptor blocker, propranolol($10^{-6}$ M). 3. The contractile response induced by electrical transmural nerve stimulation(20V, 10Hz, 0.5msec, 20sec ) was inhibited by the pretreatment with non-selective ${\alpha}$-adrenoceptor blocker, phentolamine($10^{-6}$ M) but was not inhibited and rather increased by the pretreatment ${\beta}$-adrenoceptor blocker, propranolol($10^{-6}$ M), and was not approximately effected by the pretreatment with ${\alpha}_2$-adrenoceptor blocker, yohimbine($10^{-6}$ M). These finding suggest that it was excitatory action by ${\alpha}_1$-adrenergic nerve and inhibitory action by ${\alpha}_2$-adrenergic, ${\beta}$-adrenergic nerve on uterine smooth muscle of the pig.

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MiR-150-5p Suppresses Colorectal Cancer Cell Migration and Invasion through Targeting MUC4

  • Wang, Wei-Hua;Chen, Jie;Zhao, Feng;Zhang, Bu-Rong;Yu, Hong-Sheng;Jin, Hai-Ying;Dai, Jin-Hua
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.15
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    • pp.6269-6273
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    • 2014
  • Growing evidence suggests that miR-150-5p has an important role in regulating genesis of various types of cancer. However, the roles and the underlying mechanisms of miR-150-5p in development of colorectal cancer (CRC) remain largely unknown. Transwell chambers were used to analyze effects on cell migration and invasion by miR-150-5p. Quantitative real-time PCR (qRT-PCR), Western blotting and dual-luciferase 3' UTR reporter assay were carried out to identify the target genes of miR-150-5p. In our research, miR-150-5p suppressed CRC cell migration and invasion, and MUC4 was identified as a direct target gene. Its effects were partly blocked by re-expression of MUC4. In conclusiomn, miR-150-5p may suppress CRC metastasis through directly targeting MUC4, highlighting its potential as a novel agent for the treatment of CRC metastasis.

Overload Detection and Control for Switching Systems using Fuzzy Rules

  • Rhee, Chung-Hoon;Rhee, Byung-Ho;Cho, Sung-Ho
    • The Journal of the Acoustical Society of Korea
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    • v.17 no.4E
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    • pp.28-34
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    • 1998
  • In most switching system, the processing unit is designed to work efficiently even at relatively high loads, but when the offered traffic exceeds a particular level, the rate of completed calls can fall drastically. A single call handled by the switching system consists of a sequence of events or messages that has to be processed by the control unit. The control unit is not only incapable of handling all of the offered calls, but also its call handling capability can drop as the offered load increases. The real time available for call processing is a critical resource that requires careful management. Therefore, the overloading of this resource must be detected by a subscriber in the from of a dial tone delay or an uncompleted call which is either blocked or mishandled. The subscriber may respond by either dialing prematurely or by re-attempting a call. This action can further escalate the processors load, which is spent for uncompleted calls. Unless a proper control is used, the switching system can finally break down. In this paper, we paper, we propose a fuzzy overload detection and control method for switching systems, which can by generating fuzzy rules via fuzzy aggregation networks. Simulation results involving a switching system is given.

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Losartan Inhibits Vascular Smooth Muscle Cell Proliferation through Activation of AMP-Activated Protein Kinase

  • Kim, Jung-Eun;Choi, Hyoung-Chul
    • The Korean Journal of Physiology and Pharmacology
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    • v.14 no.5
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    • pp.299-304
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    • 2010
  • Losartan is a selective angiotensin II (Ang II) type 1 ($AT_1$) receptor antagonist which inhibits vascular smooth muscle cells (VSMCs) contraction and proliferation. We hypothesized that losartan may prevent cell proliferation by activating AMP-activated protein kinase (AMPK) in VSMCs. VSMCs were treated with various concentrations of losartan. AMPK activation was measured by Western blot analysis and cell proliferation was measured by MTT assay and flowcytometry. Losartan dose- and time-dependently increased the phosphorylation of AMPK and its downstream target, acetyl-CoA carboxylase (ACC) in VSMCs. Losartan also significantly decreased the Ang II- or 15% FBS-induced VSMC proliferation by inhibiting the expression of cell cycle associated proteins, such as p-Rb, cyclin D, and cyclin E. Compound C, a specific inhibitor of AMPK, or AMPK siRNA blocked the losartan-induced inhibition of cell proliferation and the $G_0/G_1$ cell cycle arrest. These data suggest that losartan-induced AMPK activation might attenuate Ang II-induced VSMC proliferation through the inhibition of cell cycle progression.

Dynamic Reverse Route for On-Demand Routing Protocol in MANET

  • Zuhairi, Megat;Zafar, Haseeb;Harle, David
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.5
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    • pp.1354-1372
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    • 2012
  • Route establishment in Mobile Ad Hoc Network (MANET) is the key mechanism to a successful connection between a pair of source and destination nodes. An efficient routing protocol constructs routing path with minimal time, less routing overhead and capable of utilizing all possible link connectivity. In general, most on-demand MANET routing protocols operates over symmetrical and bidirectional routing path, which is infeasible due to the inherent heterogeneous properties of wireless devices. Simulation results show that the presence of unidirectional links on a network severely affect the performance of a routing protocol. In this paper, a robust protocol independent scheme is proposed, which enable immediate rediscovery of alternative route for a path blocked by a unidirectional link. The proposed scheme is efficient; route rediscovery is locally computed, which results in significant minimization of multiple route packets flooding. Nodes may exploit route information of immediate neighbors using the local reply broadcast technique, which then redirect the control packets around the unidirectional links, therefore maintaining the end-to-end bidirectional connection. The proposed scheme along with Ad Hoc On-demand Distance Vector (AODV) and AODV-Blacklist routing protocol is investigated over three types of mobility models. Simulation results show that the proposed scheme is extremely reliable under poor network conditions and the route connectivity can be improved by as much as 75%.

Throughput Analysis of Right Turn Shared Lane with Lane Width Change (차로폭에 따른 우회전 공용차로의 통과교통량분석)

  • 김동녕;김경환
    • Journal of Korean Society of Transportation
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    • v.21 no.2
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    • pp.17-31
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    • 2003
  • This study is about throughput analysis of the shared right turn lane at signalized intersection with lane width change. It is expected that the increased width of the right turn shared lane causes to increase the volume of right turn on red(RTOR) In this study, the throughput computation is designed to take into account the lost time which is caused by the blocked right turn due to the stop of through traffic. The saturation flow rate of right turn using the rest of lane after through traffic stops is included as well. Results show that the different RTOR volume levels due to the various shared lane width leads to a difference in throughput. For the shared right turn lanes. throughput capacity for various lane widths is bigger than that of the KHCM as much as from 1.1 to 2.1 times.

A Study on the Early Response System Subway Cabin Arson Fire (지하철 차량 방화사고 초기대응에 관한 연구)

  • Roh, Sam-Kew;Ham, Eun-Gu;Kim, Si-Gon
    • Fire Science and Engineering
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    • v.20 no.2 s.62
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    • pp.21-30
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    • 2006
  • Since Daegu subway arson fire disaster in 2003, there have been several copycat crimes such as at Seoul Metro line number seven and Hongkong Chuiwan line cases. Oil and gas were used for fire propagation in most cases as in Daegu case and such fire could be expanded to a whole subway cabin within several minutes. The fire may eventually cause the whole subway system stop. Fire damage can be minimized when fire occurrence and diffusion are blocked by stages or isolated rapidly. This study suggests an effective early response system that separates passengers from fire and a real-time fire extinguishment program by stages. Based on the subway arson case studies, the early response scenario has been structured by three stages, i.e., confirmation of fire and damage, early fire extinguishment, and information dissemination and passengers evacuation.