• Korean Journal of Radiology
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• 제25권3호
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• pp.314-318
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• 2024

• 대한전자공학회논문지SP
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• 제43권2호
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• pp.57-64
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• 2006

본 논문에서는 해마신경망(HCNN:HippoCampal Neural Network)을 이용하여 사용자 친화적인 객체 기반 멀티미디어 검색시스템을 제안한다. 내용 기반 검색(Content-based Retrieval)에 관한 대부분의 기존의 질의 방법은 입력 영상에 의한 질의 또는 컬러(color), 형태(shape), 질감(texture)등과 같은 low-level의 특징을 사용한다. 본 논문에서 제안하는 방법은 MPEG 기반의 압축 비디오 스트림으로부터 장면 전환 검출을 수행하여 샷을 검출한다. 이 샷 프레임에서 컬러 객체의 자동 추출을 위하여 similar colorization과 ACE(Adaptive Circular filter and Edge) 알고리즘을 사용한다. 그리고 이렇게 추출된 특징을 해마 신경망을 통하여 학습한 후 멀티미디어 검색 시스템을 구성한다. 제안하는 해마 신경망은 호감도 조정에 의해서 입력되는 영상패턴의 특징들을 흥분학습과 억제학습을 이용하여 불필요한 특징은 억제시키고 중요한 특징은 흥분학습을 통해 장기기억 시켜서 적응성 있는 실시간 검색 시스템을 구현한다.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• 제30권9호
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• pp.1350-1357
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• 2017

Objective: The present study aimed to investigate whether the long-lasting, recurrent restricting of sows leads to the physiological and psychological reaction of discomfort. Methods: Sows (Large White) that had experienced restricting for about 0.5 or 3 years and agematched sows kept in a group housing system (loose sows) were compared. Pupillary light reflex parameters were measured at the weaning stage. Immediately after slaughter, blood samples were taken to measure serum cortisol levels, and the brain was dissected, gene expression in the hippo-campus, frontal cortex and hypothalamus was analyzed. Results: The serum cortisol levels were higher in the confined sows than in the loose sows. The full maturity, but not the young adolescent, confined sows had longer latency time in the onset of pupil constriction than their loose counterparts. Real-time polymerase chain reaction analyses revealed an increased expression of interleukin 6 mRNA in the hippocampus and decreased expression of brain derived neurotrophic factor mRNA in hippocampus and hypothalamus and to a lesser extent in the frontal cortex of the full maturity confined sows, compared with the full maturity loose sows. Conclusion: Taken together, these data indicated that recurrent restricting stress in full maturity sows leads to the physiological and psychological reaction of discomfort.

• The Korean Journal of Physiology and Pharmacology
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• 제8권1호
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• pp.1-5
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• 2004

Transient forebrain ischemia results in the delayed neuronal death in the CA1 area of the hippo-campus. The present study was performed to determine effects of aminoguanidine, a selective iNOS inhibitor, on the generation of peroxynitrite and delayed neuronal death occurring in the hippocampus following transient forebrain ischemia. Transient forebrain ischemia was produced in the conscious rats by four-vessel occlusion for 10 min. Treatment with aminoguanidine (100 mg/kg or 200 mg/kg, i.p.) or saline (0.4 ml/100 g, i.p.) was started 30 min following ischemia-reperfusion and the animals were then injected twice daily until 12 h before sacrifice. Immunohistochemical method was used to detect 3-nitrotyrosine, a marker of peroxynitrite production. Posttreatment of aminoguanidine (200 mg/kg) significantly attenuated the neuronal death in the hippocampal CA1 area 3 days, but not 7 days, after ischemia-reperfusion. 3-Nitrotyrosine immunoreactivity was enhanced in the hippocampal CA1 area 3 days after reperfusion, which was prevented by the treatment of aminoguanidine (100 mg/kg and 200 mg/kg). Our findings showed that (1) the generation of peroxynitrite in the hippocampal CA1 area 3 days after ischemia-reperfusion was dependent on the iNOS activity; (2) the postischemic delayed neuronal death was attenuated in the early phase through the prevention of peroxynitrite generation by an iNOS inhibitor.

• Applied Microscopy
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• 제38권1호
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• pp.29-34
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• 2008

본 연구자는 Zinc Selenium autometallography ($ZnSe^{AMG}$) (Danscher et al., 1997) 염색법을 중심으로 중추신경계통 내 zinc ($Zn^{2+}$)의 분포와 이들을 함유하고 있는 신경종말, 소위 ZEN(zinc-enriched) terminals의 미세구조에 관하여 보고한 바 있다. 이번 연구에서는 다른 몇 가지, 즉 Neo-Timm staining (Danscher, 1982), TSQ fluorescence staining (Frederickson et al.,1987), Zinc transporter-3 Immunohistochemistry ($ZnT3^{IHC}$) (Palmiter et at., 1997) 염색법으로 흰쥐 해마복합체에 분포하는 $Zn^{2+}$를 염색한 후 이들의 염색패턴에서 차이점을 밝히고자 하였다. $ZnSe^{AMG}$ 염색법은 $Zn^{2+}$에 대한 특이성은 다소 떨어지나 광학 및 전자현미경하에서 관찰이 가능하며, 반영구적인 표본으로 보관이 가능하다는 장점이 있었고, TSQ는 $Zn^{2+}$에 대한 특이성이 매우 높을 뿐 아니라 그 염색법이 매우 간단하다는 장점이 있는 반면 형광물질의 안정성과 표본보관이 용이하지 않다는 단점이 있다. 그 외 Neo-Timm 염색법은 TSQ형광염색법과 유사한 염색 패턴을 보였으며, $ZnT3^{IHC}$염색법은 오히려 $ZnSe^{AMG}$에 가까운 염색의 결과를 보였다. 본 연구의 결과는 중추신경계통 내 $Zn^{2+}$에 관한 형태학적 연구에서 기초자료로 활용될 수 있을 것이다.