• Title/Summary/Keyword: Number of neurons

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Postembryonic Changes of Locustatachykinin I-immunoreactive Neurons in the Brains of the Moth Spodoptera litura

  • Kang, Hyun-O;Lee, Jeong-Oon;Lee, Bong-Hee
    • Animal cells and systems
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    • v.1 no.3
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    • pp.475-482
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    • 1997
  • The antiserum against locustatachykinin I, originally isolated from brain and retrocerebral complex of the locust Locusta migratoria, has been used to investigate changes in number, localization, and structure of locustatachykinin I-immunoreactive (LomTK I-IR) neurons in the brains of the common cutworm, Spodoptera Iitura, during postembryonic development. These neurons are found at larval, pupal, and adult stages. In the larval stages, the first instar larva shows the first appearance of about 8 LomTK I-IR neurons. These neurons gradually increase in number from the second to fourth instar larvae which have the largest number of about 92 in all postembryonic stages. Thereafter, these neurons decrease to about 28 in number in the 5-day-old pupa. However, they begin to rise again from the 7-day-old pupal stage, eventually reaching to about 90 in the l-day-old adult. The developing larval brains contain cell bodies of these neurons in most neuromeres. After the metamorphosis of larva to pupa and adult, localization of these neuronal cell bodies is confined to the specific cerebral neuromeres. The 7-day-old pupal brain shows the location of these neuronal cell bodies in pars intercerebralis, pars lateralis of protocerebrum, deutocerebrum, tritocerebrum, optic lobe-near region, and subesophageal ganglion. In the l-day-old adult, however, the brain has these cell bodies only in some neuromeres of protocerebrum, deutocerebrum, and subesophageal ganglion. Throughout the postembryonic life, changes in structure of these neurons coincide with changes in number and localization of these neurons. These findings suggest that changes in number, localization, and structure of these neurons reflect differentiation of these neurons to adult type.

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A Method for Optimizing the Structure of Neural Networks Based on Information Entropy

  • Yuan Hongchun;Xiong Fanlnu;Kei, Bai-Shi
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2001.01a
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    • pp.30-33
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    • 2001
  • The number of hidden neurons of the feed-forward neural networks is generally decided on the basis of experience. The method usually results in the lack or redundancy of hidden neurons, and causes the shortage of capacity for storing information of learning overmuch. This research proposes a new method for optimizing the number of hidden neurons bases on information entropy, Firstly, an initial neural network with enough hidden neurons should be trained by a set of training samples. Second, the activation values of hidden neurons should be calculated by inputting the training samples that can be identified correctly by the trained neural network. Third, all kinds of partitions should be tried and its information gain should be calculated, and then a decision-tree correctly dividing the whole sample space can be constructed. Finally, the important and related hidden neurons that are included in the tree can be found by searching the whole tree, and other redundant hidden neurons can be deleted. Thus, the number of hidden neurons can be decided. In the case of building a neural network with the best number of hidden units for tea quality evaluation, the proposed method is applied. And the result shows that the method is effective

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Effects of GR89696 on parvalbumin positive neurons after cerebral ischemia in the Mongolian gerbil (몽고리안 저빌에서 뇌허혈시 GR89696이 parvalbumin 발현 신경세포에 미치는 영향)

  • Kwon, Young-bae;Yang, Il-suk;Lee, Jang-hern
    • Korean Journal of Veterinary Research
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    • v.39 no.1
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    • pp.34-44
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    • 1999
  • Ischemic damage in the selectively vulnerable populations of neurons is thought to be caused by an abnormal accumulation of intracellular calcium. It has been reported that the neurons, expressing specific calcium binding proteins, might effectively control intracellular calcium concentrations because of a high capacity to buffer intracellular calcium in the brain ischemic condition. It is uncertain that parvalbumin, one of the calcium binding proteins, can protect the neurons from the cerebral ischemic damage. Recently, treatment of kappa opioid agonists increased survival rate, improved neurological function, and decreased tissue damage under the cerebral ischemic condition. Many evidences indicate that these therapeutic effects might result from regulation of calcium concentration. This study was designed to analyze the changes of number in parvalbumin-positive neurons after cerebral ischemic damage according to timepoints after cerebral ischemic induction. In addition, we evaluated the effect of GR89696 (kappa opioid agonist) or naltrexone(non selective opioid antagonist) on the changes of number in parvalbumin expressing neurons under ischemic condition. Cerebral ischemia was induced by occluding the common carotid artery of experimental animals. The hippocampal areas were morphometrically analyzed at different time point after ischemic induction(1, 3, 5 days) by using immuno-histochemical technique and imaging analysis system. The number of parvalbumin-positive neurons in hippocampus was significantly reduced at 1 day after ischemia(p<0.05). Furthermore, the number of parvalbumin-immunoreactive neurons was dramatically reduced at 3 and 5 days after cerebral ischemic induction(p<0.05) as compared to 1 day group after ischemia, as well as sham control group. Significant reduction of parvalbumin positive neurons in CA1 region of hippocampus was observed at 1 day after cerebral ischemic induction. However, significant loss of MAP2 immunoreactivity was observed at 3 day after cerebral ischemia. The loss of parvalbumin-positive neurons and MAP2 immunoreactivity in CA1 region was prevented by pre-administration of GR89696 compared to that of saline-treated ischemic group. Furthermore, protective effect of GR89696 partially reversed by pre-treatment of naltrexone. These data indicate that parvalbumin-positive neurons more sensitively responded to cerebral ischemic damage than MAP2 protein. Moreover, this loss of parvalbumin-positive neurons was effectively prevented by the pretreatment of kappa opioid agonist. It was also suggested that the changes of number in parvalbumin-positive neurons could be used as the specific marker to analyze the degree of ischemic neuronal damage.

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Effects of Panax ginseng Radix herb-acupuncture on c-fos expression in the hippocampus of ethanol-intoxicated Sprague-Dawley rats (인삼(人蔘) 약침(藥鍼)이 에탄올 중독 흰쥐의 해마에서 c-fos 생성에 미치는 영향)

  • Kim, Min-soo;Lee, Eun-yong
    • Journal of Acupuncture Research
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    • v.20 no.3
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    • pp.131-140
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    • 2003
  • Objective : The purpose of this study is to investigate the effect of Panax ginseng Radix herb-acupuncture on c-fos expression in each area of the hippocampus of acutely ethanol-intoxicated rats. Methods : Twenty-four male Sprague-Dawley tats were divided into untreated(normal), ethanol-treated(control), Panax ginseng Radix-treated(sample A), ethanol-and Panax gingseng Radix-treated(sample B) groups. Each group was evaluated by the changes of c-fos-positive neurons in each area of the hippocampus by using and image analyzer and microscope. Results : 1. In the CA1 area, the number of c-fos-positive neurons in the control group was diminished compared with the normal group. The number of c-fos-positive neurons in the sample B group had no marked difference from the control group. 2. In the CA2-3 area, the number of c-fos-positive neurons in the control group was diminished compared with the normal group, The number of c-fos-positive neurons in the sample B group was increased compared with the control group. 3. In the Dentate gyrus area, the number of c-fos-positive neurons in the control group was diminished compared with the normal group. The number of c-fos-positive neurons in the sample B group was increased compared with the control group. Conclusions : These results indicate that, c-fos expression in each area of the hippocampus was reduced in ethanol-intoxicated group. Treatment of Panax ginseng Radix herb-acupuncture increased this diminution. Panax ginseng Radix could be able to effect on the prevention of the amnesia and learning disability in alcoholism.

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Postembryonic Development of Leucokinin I-Producing Neurons in the Brain of Insect Spldoptera litura

  • Kang, Hyu-No;Lee, Bong-Hee
    • Animal cells and systems
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    • v.1 no.1
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    • pp.107-113
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    • 1997
  • Antisera against the myotropic neuropeptide leucokinin I, originally isolated from head extracts of the cockroach Leucophaea maderae, have been used to investigate the distribution of the leucokinin I-immunoreactive (LK I-IR) neurons in the brain of the common cutworm, Spodoptera Iitura, during postembryonic development. The LK I-IR neurons are found at the larval stages (excluding first instar larval stage), pupal stages, and adult stage, of which the brains have been examined in this experiment. The number of the LK I-IR neurons in the brain increases from the second instar larva to the fifth instar larva which has about 32, the largest number in all postembryonic stages. Thereafter, the LK I-IR neurons begin to decrease in number. During the pupal stages, smaller number of LK I-IR neurons persist in the brains; 6 or 4. At adult stage the brain contains 8 LK I-IR neurons. The LK I-IR cell bodies are distributed in each dorsal cortex of both cerebral hemispheres in the second instar larva and through all the neuromeres of the brain during later larval stages, despite of being a large number of the LK I-IR cell bodies in dorsolateral neuromeres. At pupal stages, most of the LK I-IR cell bodies are found in the pars intercerebralis. Extremely small number of the LK I-IR cell bodies are localized in the pars lateral is. Adult brain contains the LK I-IR cell bodies in the pars intercerebralis and the middle cortex of the posterior brain. The LK I-IR nerve processes can be easily found in the neuropils of almost all the neuromeres in the brains of third, fourth, fifth and sixth instar larvae. Most of the LK I-IR nerve fibers in those brains are originated from the LK I-IR cell bodies located in the brains. The LK I-IR cell bodies which have very weak reactivities to the antisera do not show projection of the LK I-IR nerve processes in the brains.

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Effect of the bee venom aqua-acupuncture on the neuronal activities of catecholaminergic system in brainstem (봉독약침자극이 Catecholamine성 신경세포의 활성변화에 미치는 영향)

  • Kim, Hye-Nam;Nam, Sang-Soo;Lee, Yun-Hoo;Choi, Yong-Tae
    • Journal of Pharmacopuncture
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    • v.3 no.1
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    • pp.65-87
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    • 2000
  • This study was designed to evaluate the effect of the bee venom(BV) aqua-acupuncture on the neuronal activities of catecholaminergic(tyrosine hydroxylase : TH, dopamine ${\beta}$ hydroxylase : D${\beta}$H) system in the brainstem. After the BV aqua-acupuncture was applied on Chok-Samni(ST36) and the gluteal part(Blank locus) in rats. Also, the number of colocalization between catecholamine containing neurons and Fos immunoreactive neurons were analyzed by using the double immunohistochemical technique. The results of the experiments were summarized as follows : 1. In DR and LC, Chok-Samni group and the Blank locus group showed more significant increase in the number of colocalization between TH containing neurons and Fos immunoreactive neurons than the control group. Furthermore, Chok-Samni group showed more significant increase than the Blank locus group. Also, in Arc, Chok-Samni group showed more significant increase than the Blank locus group and the control group. 2. In LC, Chok-Samni group showed more significant increase in the number of colocalization between D${\beta}$H containing neurons and Fos immunoreactive neurons than the Blank locus group and the control group. Also, in A5, Chok-Samni group and the Blank locus group showed more significant increase than the control group. Chok-Samni group showed more significant increase than the Blank locus group. However, there was no significant change in A7. Consequently, the BV aqua-acupuncture increased more potent the number of Fos immunoreactive neurons and the activity of catecholaminergic neurons. Furthermore, the BV aqua-acupuncture was more effective on Chok-Samni than Blank locus group. These results indicate that the BV aqua-acupuncture is very effective therapy to control pain. The therapeutic effect of BV aqua-acupunture may associated with the endogenous modulatory system such as catecholamine. Those data from the study can be applied to establish the effective treatment of the BV for pain control in the clinical field.

Immunocytochemical Localization of Glutamatergic Neurons in the Lateral Reticular Nucleus Projecting to Ansiform (Crus I and II) and Paramedian Cerebellar Lobules of the Rat

  • Lee, Hyun-Sook
    • Animal cells and systems
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    • v.2 no.1
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    • pp.139-144
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    • 1998
  • I examined the projection of glutamatergic neurons in the lateral reticular nucleus into ansiform (crus l and ll) and paramedian lobules in the rat cerebellum using immunocytochemical methods with antiserum against glutamate combined with WGA-HRP histochemistry. The projections of glutamatergic neurons from the lateral reticular nucleus to crus l were most extensive in number among the three injection cases and the majority of projections originated at the dorsal to dorsomedial region of the ipsilateral magnocellular nucleus. Glutamate-immunoreactive cells projecting to crus ll were less extensive in number than those projecting to crus l and were mainly localized at the dorsomedial portion of the ipsilateral magnocellular nucleus. Double-labelled neurons projecting to crus l or crux ll were also located at ipsilateral subtrigeminal as well as contralateral magnocellular nuclei. Glutamatergic neurons projecting to paramedian lobules were moderate in number and mainly located at the dorsal area of the ipsilateral magnocellular nucleus. A few double-labelled cells were also found at ipsilateral subtrigeminal or contralateral magnocellular nuclei. The present study suggests that glutamate-immunoreactive neurons at the dorsal to dorsomedial magnocellular division of the lateral reticular nucleus may participate in the excitatory control of target neuronal activities at ipsilateral, posterior hemispheric lobules of the rat cerebellum.

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Ginsenosides Have a Suppressive Effect on c-Fos Expression in Brain and Reduce Cardiovascular Responses Increased by Noxious Stimulation to the Rat Tooth

  • Jung, Ji-Yeon;Seong, Kyung-Joo;Moon, In-Ohk;Cho, Jin-Hyoung;Kim, Sun-Hun;Kim, Won-Jae
    • The Korean Journal of Physiology and Pharmacology
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    • v.17 no.2
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    • pp.121-125
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    • 2013
  • The purpose of this study is to investigate the antinociceptive effects of ginsenosides on toothache. c-Fos immunoreactive (IR) neurons were examined after noxious intrapulpal stimulation (NS) by intrapulpal injection of 2 M KCl into upper and lower incisor pulps exposed by bone cutter in Sprague Dawley rats. The number of Fos-IR neurons was increased in the trigeminal subnucleus caudalis (Vc) and the transitional region between Vc and subnucleus interpolaris (Vi) by NS to tooth. The intradental NS raised arterial blood pressure (BP) and heart rate (HR). The number of Fos-IR neurons was also enhanced in thalamic ventral posteromedial nucleus (VPMN) and centrolateral nucleus (CLN) by NS to tooth. The intradental NS increased the number of Fos-IR neurons in the nucleus tractus solitarius (NTS) and rostral ventrolateral medulla (RVLM), hypothalamic supraoptic nucleus (SON) and paraventricular nucleus (PVN), central cardiovascular regulation centers. Ginsenosides reduced the number of c-Fos-IR increased by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Naloxone, an opioid antagonist, did not block the effect of ginsenoside on the number of Fos-IR neurons enhanced by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Ginsenosides ameliorated arterial BP and HR raised by NS to tooth and reduced the number of Fos-IR neurons increased by NS to tooth in the NTS, RVLM, hypothalamic SON, and PVN. These results suggest that ginsenosides have an antinociceptive effect on toothache through non-opioid system and attenuates BP and HR increased by NS to tooth.

Improving LTC using Markov Chain Model of Sensory Neurons and Synaptic Plasticity (감각 뉴런의 마르코프 체인 모델과 시냅스 가소성을 이용한 LTC 개선)

  • Lee, Junhyeok
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2022.10a
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    • pp.150-152
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    • 2022
  • In this work, we propose a model that considers the behavior and synaptic plasticity of sensory neurons based on Liquid Time-constant Network (LTC). The neuron connection structure was experimented with four types: the increasing number of neurons, the decreasing number, the decreasing number, and the decreasing number. In this study, we experimented using a time series prediction dataset to see if the performance of the changed model improved compared to LTC. Experimental results show that the application of modeling of sensory neurons does not always bring about performance improvements, but improves performance through proper selection of learning rules depending on the type of dataset. In addition, the connective structure of neurons showed improved performance when it was less than four layers.

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The Effects of Chungpesagan-Tang Extracts on Reversible Forebrain Ischemia in Sprague-Dawley Rats (청폐사간탕(淸肺瀉肝湯)이 중대뇌동맥 폐쇄 후 재관류에 미치는 영향)

  • Oh, Yean-Hwan;Park, In-Sick;Shin, Gil-Cho;Lee, Won-Chul;Jeong, Sung-Hyun
    • The Journal of Internal Korean Medicine
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    • v.22 no.2
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    • pp.161-174
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    • 2001
  • Objectives : The purpose of this investigation is to evaluate the effect of Chungpesagan-Tang Extracts on reversible forebrain ischemia in Sprague-Dawley rats. Methods : the volume of cerebral infarction and edema, the pathohistological change of neurons, the number of survived neurons, neurotransmitters through immunohistochemical methods, proteins connected with neurotransmitters through immunohistochemical methods and the pathohistological change of neurons through electro-microscopy were investigated. From these reseach data, the protection of neurons and the activity of brain cells were examined. Results : 1. The infaction volume of the control group was 23.9%, and that of the sample group was 16%. 2. The brain edema volume of the control group increased by 17% compared to the normal group and that of the sample group increased by 10%. 3. The light microscopy revealed that the neurons in the ischemia-induced area and CA1 area of hippocampus were most heavily damaged and that the sample group was less damaged compared with the control group. Most pyramidal neurons died in 7 days when brain ischemia was induced. 4. The number of survived pyramidal neurons in the CA1 area of the hippocampus were studied. The normal group had 93 neurons/mm, survived the control group(after 3 days) had 21/mm, the control group(after 7 days) had 3/mm and the sample group 33/mm. 5. The immunohistochemical methods revealed that: (1) In the control group, the sensitivity of GABA, NOS, DBH were increased, and those of Synapsin, eEF-$1{\alpha}$ decreased. NOS and DBH had positive reactions in the control group, but negative in the normal group. (2) In thd sample group, the sensitivity of GABA, NOS, DBH were attenuated, and those of NPY, Synapsin, CaMKII, eEF-$1{\alpha}$ increased when compared to the control group. 6. The electro-microscopy revealed that most neurons died by necrosis and some neurons died by apoptosis. Several imflammation cells appeared in the injured area of neurons. The number of neurons in the sample group that died by ischemia decreased. But, the number that died by apoptosis did not significantly change. Conclusions : The data shows that the effect of Chungpesagan-Tang Extracts on reversible forebrain ischemia in Sprague-Dawley rats is significant.

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