• Animal cells and systems
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• 제2권1호
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• pp.65-69
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• 1998

The hippocampus and prefrontal cortex are regarded as the highest-order association cortices. The hippocampus has been proposed to store "cognitive maps" of external environments, and the prefrontal cortex is known to be involved in the planning of behavior, among other functions. Considering the prominent functional roles played by these structures, it is not surprising to find direct monosynaptic projections from the hippocampus to the prefrontal cortex. Rhythmic stimulation of this projection patterned after the hippocampal EEG theta rhythm induced stable long-term potentiation of field potentials in the prefrontal cortex. Comparison of behavioral correlates of hippocampal and prefrontal cortical neurons during an a-arm radial maze, working memory task shows a striking contrast. Hippocampal neurons exhibit clear place-specific firing patterns, whereas prefrontal cortical neurons do not show spatial selectivity, but are correlated to different stages of the behavioral task. These data lead to the hypothesis that the role of hippocampal projection to the prefrontal cortex is not to impose spatial representations upon prefrontal activity, but to provide a mechanism for learning the spatial context in which particular behaviors are appropriate.propriate.

• 한국멀티미디어학회논문지
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• 제15권12호
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• pp.1449-1455
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• 2012

This paper has developed a system for early diagnosis of senile dementia and mild cognitive impairment (MCI) by developing software to measure the volume of hippocampus. This software consists of two parts; segmentation and analysis. The segmentation part uses ROI and region growing to segment hippocampus region. On the other hand, the analysis part creates a volume rendering of hippocampus. This software is expected contribute in these research fields for dementia diagnosis and its medication planning.

• 한국어류학회지
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• 제25권1호
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• pp.42-45
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• 2013

거문도 연안에서 채집된 해마속의 어류를 근거로 Hippocampus sindonis를 한국에서의 미기록종으로 보고하였다. 본 종은 등지느러미 기조수 15개, 가슴지느러미 기조수 14개이며, 10개의 몸통 체륜과, 37개의 꼬리 체륜 등을 가지는 특징에 의해 국내의 유사종과 구별되며, 국명은 "신도해마"로 명명하였다.

• 한국멀티미디어학회논문지
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• 제17권5호
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• pp.566-572
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• 2014

The hippocampus has been known as one of the most important structure related to many neurological disorders, such as Alzheimer's disease. This paper presents the snake model to segment hippocampus from brain MRI. The snake model or active contour model is widely used in medical image processing fields, especially image segmentation they look onto nearby edge, localizing them accurately. We applied a snake model on brain MRI. Then we compared our results with an active shape approach. The results show that hippocampus was successfully segmented by the snake model.

• Kidney Research and Clinical Practice
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• 제37권4호
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• pp.315-322
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• 2018

The high mortality rates associated with acute kidney injury are mainly due to extra-renal complications that occur following distant-organ involvement. Damage to these organs, which is commonly referred to as multiple organ dysfunction syndrome, has more severe and persistent effects. The brain and its sub-structures, such as the hippocampus, are vulnerable organs that can be adversely affected. Acute kidney injury may be associated with numerous brain and hippocampal complications, as it may alter the permeability of the blood-brain barrier. Although the pathogenesis of acute uremic encephalopathy is poorly understood, some of the underlying mechanisms that may contribute to hippocampal involvement include the release of multiple inflammatory mediators that coincide with hippocampus inflammation and cytotoxicity, neurotransmitter derangement, transcriptional dysregulation, and changes in the expression of apoptotic genes. Impairment of brain function, especially of a structure that has vital activity in learning and memory and is very sensitive to renal ischemic injury, can ultimately lead to cognitive and functional complications in patients with acute kidney injury. The objective of this review was to assess these complications in the brain following acute kidney injury, with a focus on the hippocampus as a critical region for learning and memory.

• BMB Reports
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• 제44권5호
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• pp.306-311
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• 2011

Although NCX-3 is highly expressed in the brain, the distribution of NCX-3 in the epileptic hippocampus is still controversial. Therefore, to assess the distribution and pattern of NCX-3 expression in epileptic hippocampus, we performed a comparative analysis of NCX-3 immunoreactivities in the hippocampus of seizure-resistant (SR) and seizure-sensitive (SS) gerbils. In SR gerbils, NCX-3 immunoreactivity was higher than pre-seizure SS gerbils, particularly in the pavalbumin (PV)-positive interneurons. Three h post-ictal, NCX-3 immunoreactivity in the SS gerbil hippocampus was markedly elevated to the level of SR gerbils. Six h post-ictal, the expression of NCX-3 was reduced to the level of pre-seizure SS gerbils. Therefore, the results of the present study suggest that down-regulation of NCX-3 expression in the SS gerbil hippo-campus may be involved in the hyperexcitability of SS gerbils due to an imbalance of intracellular $Na^+/Ca^{2+}$ homeostasis and $Ca^{2+}$ concentration.

• 대한한방내과학회지
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• 제24권2호
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• pp.337-347
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• 2003

This study investigated the effect of Yanggyuksanhwa-tang on cerebral ischemia of the rats. Considering age-related impact on cerebral ischemia, aged rats (18 months old) were used for this study. Ischemic damage was induced by the transient occlusion of bilateral common carotid arteries(BCAO) under the hypotension. Yanggyuksanhwa-tang was administered twice orally. Then changes of immunohistochemical expression of c-fos and c-jun in ischemic damaged hippocampus were observed. The BCAO in aged rats led significant increase of c-fos expression in CA1 and DG of hippocampus. While the treatment of Yanggyuksanhwa-tang significantly attenuated the increase of c-fos expression in CA1 hippocampus following BCAO ischemia. Depending on changes of the normalized optical density(NOD) of immunohistochemical c-fos expression, the treatment of Yanggyuksanhwa-tang significantly attenuated the increase of NOD in CA1 and DG of hippocampus. And there was not changes in CA2 and CA3 hippocampus with respect to the control BCAO group. The BCAO in aged rats led significant increase of c-jun expression in CA1 hippocampus. While the treatment of Yanggyuksanhwa-tang significantly attenuated the increase of c-jun expression in CA1 hippocampus following BCAO ischemia. Depending on changes of the NOD of immunohistochemical c-jun expression, the treatment of Yanggyuksanhwa-tang significantly attenuated the increase of NOD in CA1 hippocampus. And there was not changes in CA2, CA3 and DG of hippocampus with respect to the control BCAO group.

• The Korean Journal of Physiology and Pharmacology
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• 제8권3호
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• pp.141-146
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• 2004

Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) proteins, composed of two presynaptic membrane proteins [synaptosomal-associated protein of 25 kDa (SNAP-25) and syntaxin] and a presynaptic vesicular protein [vesicle-associated membrane protein (VAMP)], serve as a core of exocytotic fusion machinery, which can be affected by ischemia. Synaptic protein in core region, striatum and cortex has been shown to alter after focal ischemia, however, little is known in hippocampus. Hippocampus is remote from ischemic core, but it is one of the most vulnerable regions. Using immunohistochemistry, the present study was undertaken to investigate the alteration of expression of SNAP-25, syntaxin, and VAMP in the hippocampus of rats which were subjected to middle cerebral artery occlusion (MCAO) for 2h and allowed to reperfuse. At 2 weeks of reperfusion, the SNAP-25 and syntaxin immunoreactivity was increased in the stratum oriens of the CA1 and the stratum lucidum of the CA3 in the ipsilateral hippocampus. However, VAMP immunoreactivity didn't show significant change. These results demonstrate that the level of the presynatpic plasma membrane proteins (SNAP-25 and syntaxin) in the rat hippocampus is more sensitively affected by focal ischemia than that of the synaptic vesicle protein (VAMP).

• Journal of Nutrition and Health
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• 제35권1호
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• pp.24-29
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• 2002

본 연구에서는 녹차 건분 식이가 뇌 조직에서 알코올에 의한 산화적 스트레스 감소효과를 나타내는 지를 규명하고 자, 생후 9개월령 Sprague-Dawley에게 1% 녹차 건분식이를 4주간 공급하고 희생 12시간 전메 급성으로 알코올을 투여한 후 뇌 조직을 cortex, cerebellum, striatum, hippocampus로 나누어 malondialdehyde(MDA)의 함량과 catalase. superoxide dismutase(SOD), glutathione peroxidase(GSH-Px)의 활성을 측정하였다. 본 실험 결과를 종합하여 볼 때. 1%녹차 건분 식이의 공급은 striatum과 hippocampus 내 MDA 함량을 유의적으로 낮추고 알코올에 따른 hippocampus 내 catalase 활성 증가를 유의적으로 억제하였다. 이러한 곁과는 녹차 건분의 공급이 알코올로 산화적 stress를 가한 동물에서 일부 뇌 조직의 지질 산화를 감소시키고 알코올에 의한 뇌 조직 손상으로부터 보호할 수 있음을 보여준다.

• Genomics & Informatics
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• 제4권1호
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• pp.23-32
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• 2006

In order to investigate the molecular basis of the aging process in brain, we have employed high-density oligonucleotide microarrays providing data on 10,108 gene clusters to define transcriptional patterns in three brain regions, cerebral cortex, cerebellum, and hippocampus. Comparison of the expression patterns between young (6-week-old) and aged (17-month-old) C57BL/6 male micerevealed that about ten percent (1098) of the genes showed a significant change in the expression level in at least one of the three tissues. Among them, 23 genes were upregulated and 62 genes were downregulated in all three tissues of the old mice. The number of genes upregulated exclusively in hippocampus (337) was much larger compared to other tissues. Gene ontology-based analysis showed the genes related with signal transduction or molecular transports are more likely to be upregulated than downregulated in the aging process of hippocampus. These data may provide some useful means for elucidating the molecular aspect of aging in hippocampus and other regions in brain.