• Journal of Korean Neurosurgical Society
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• 제55권3호
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• pp.131-135
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• 2014

Objective : With the growing interests of bacteria as a targeting vector for cancer treatment, diverse genetically engineered Salmonella has been reported to be capable of targeting primary or metastatic tumor regions after intravenous injection into mouse tumor models. The purpose of this study was to investigate the capability of the genetically engineered Salmonella typhimurium (S. typhimurium) to access the glioma xenograft, which was monitored in mouse brain tumor models using optical bioluminescence imaging technique. Methods : U87 malignant glioma cells (U87-MG) stably transfected with firefly luciferase (Fluc) were implanted into BALB/cAnN nude mice by stereotactic injection into the striatum. After tumor formation, attenuated S. typhimurium expressing bacterial luciferase (Lux) was injected into the tail vein. Bioluminescence signals from transfected cells or bacteria were monitored using a cooled charge-coupled device camera to identify the tumor location or to trace the bacterial migration. Immunofluorescence staining was also performed in frozen sections of mouse glioma xenograft. Results : The injected S. typhimurium exclusively localized in the glioma xenograft region of U87-MG-bearing mouse. Immunofluorescence staining also demonstrated the accumulation of S. typhimurium in the brain tumors. Conclusion : The present study demonstrated that S. typhimurium can target glioma xenograft, and may provide a potentially therapeutic probe for glioma.

• Archives of Pharmacal Research
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• 제8권1호
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• pp.45-48
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• 1985

The amount of norepinephrine and dopamine in the brain of the mouse fed with normal diet or protein deficient diet with supplement of the saponin fraction of ginseng were determined by the sluorometric method. THe amount of norepinephrine in mouse brain was vivider in the case of protein deficiency. The increase amount of dopamine was observed only in the case of mouse fed with normal diet with supplement of the saponin fraction normal diet with supplement of the saponin fraction of ginseng for 8 weeks.

• 대한수의학회지
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• 제44권3호
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• pp.335-341
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• 2004

This study was undertaken to examine the developmental expression of osteopontin(OPN) in the mouse brain. In Western blotting analysis, the expression of OPN was noted initially at embryonic stage and increased gradually after birth and decreased at postnatal day 60(P60). In immunohistochemistry, OPN expression was found in the interstitial nucleus Cajal and the substantia nigra reticularis in anterior part of the brain and in the inferior olivary complex, the parabrachial nucleus, the facial nucleus, the gigantocellular reticular nucleus, the trigeminal nucleus and the anterior interposed nucleus in posterior part of the brain at P31 and P60. In addition, OPN expression in widespread neurons appeared during the period of neuronal differentiation, increased just after birth and decreased with maturation. These results suggest that OPN contributes to developmental processes, including the differentiation and maturation of specific neuronal populations.

• Toxicological Research
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• 제13권4호
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• pp.417-421
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• 1997

Synaptobrevin is a kind of vesicle associated membrane proteins (VAMPs) which plays a secretary role in the neuronal synapse and was recently known as the biochemical target of botulinum neurotoxin type B. The structural gene of the synaptobrevin was cloned from mouse brain using RT-PCR technique and was seqrtenced. The deduced amino acid sequence showed that the synaptobrevin protein from mouse brain is exactly the same with that of the rat brain in the amino acid level. The synaptobrevin gene was subcloned into pET3a vector and expressed in E. coli. The molecular weight of the recombinant protein was 19 kDa as expected. Moreover, when the recombinant synaptobrevin protein was incubated with the native neurotoxin of Clostridium botulinum type B, it was cleaved by the toxin in a time dependent manner. This implies that the recombinant synaptobrevin protein and the native toxin are reacted in the same way as the native synaptobrevin did in the neuronal cells.

• Toxicological Research
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• 제17권4호
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• pp.303-308
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• 2001

The potential for a given anticholinesterase pesticide to exhibit age-related toxicity is essential information for an accurate and proper risk assessment of that compound. This investigation was designed to study the age-related toxicity of active metabolites of four organophosphates using in vitro detoxification measurement. The blood samples were collected from 1 month and 18 months old rats. The $IC_{50}$ values of mouse brain recombinant AChE of chlorpyrifos-oxon, diazoxon, malaoxon and paraoxon were 10.35, 112.84, 151.28 and 18.43 nM, respectively. When the plasma of young rats, and $CaCI_2$were added, the $IC_{50}$ values of mouse brain recombinant AChE of chlorpyrfos-oxon, diazoxon, malaoxon and paraoxon were 31.89, 164.25, 139.94 and 16.36 nM, respectively. The $IC_{50}$ values of mouse brain recombinant AChE of chlorpyrifos-oxon, diazoxon, malaoxon and paraoxon were changed to 136.840, 1244.45, 654.54 and 52.66 nM by A-esterases In adult rats. These results suggest that four organophosphates have a potential toxicity to exhibit age-related sensitivity.

• Journal of Ginseng Research
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• 제14권3호
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• pp.399-403
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• 1990

This study was undertaken to investigate the effect of ginseng total sapoin (GTS) on locomotor activity that had been increased by caffeine. Catecholamines, noradrenaline and dopamine, possible mediators for the locomotor activity, were measllred in the mouse whole brain, cortex and the re- mainder. The locomotor activity was measured in circlllar activity cages equipped with six light sources and photocells. The catecholamine contents in the mollse brain were determined by HPLC-fluorescence detection. GTS (50 and 100 mg/kg) reduced the increased locomotor activity by caffeine (25 mg/kg) dose-devendently. Caffeine increased the norevinephrint and dopamine in mouse whole brain and cortex dose-dependently. GTS reduced the norevinevhrine in the remainder, and reduced the dopamine in the cortex which had been increased by caffeine.

• 생명과학회지
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• 제8권1호
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• pp.109-117
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• 1998

The synthesis and methylation in vivo of myleline basic protein(MBP) during the mouse brain devlopment was found to be the highest in youngest brain and declined progressively in mature brains. The relative rate of protein synthesis and methylation was a maximal ration in the youngest brain, This high ratio was wdll correlated with the higher protein methylase I (PM I) activity in younger brains. The jimpy mouse is the most severely affected dysmyelinating mutant and is characterized by failure to incorporate MBP into myelin. sheath. The MBP-specific PM I activity in 15-, 18-, and 21-days old hemizygous jimpy mice(jp/y)brains decreased by 20, 50 and 75%, respectively. Myelin fraction with different degrees of compaction were isolated from bovine brain, the most compact myelin fraction exhibited higher methylaccepting activity than the less compact dense fractions.

• Journal of Radiation Protection and Research
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• 제38권4호
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• pp.166-171
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• 2013

While high-dose ionizing radiation results in long term cellular cytotoxicity, chronic low-dose (<0.2 Gy) of X- or ${\gamma}$-ray irradiation can be beneficial to living organisms by inducing radiation hormesis, stimulating immune function, and adaptive responses. During chronic low-dose-rate radiation (LDR) exposure, whole body of mice is exposed to radiation, however, it remains unclear if LDR causes changes in gene expression of the whole brain. Therefore, we aim to investigate expressed genes (EGs) and signaling pathways specifically regulated by LDR-irradiation ($^{137}Cs$, a cumulative dose of 1.7 Gy for total 100 days) in the whole brain. Using microarray analysis of whole brain RNA extracts harvested from ICR and AKR/J mice after LDR-irradiation, we discovered that two mice strains displayed distinct gene regulation patterns upon LDR-irradiation. In ICR mice, genes involved in ion transport, transition metal ion transport, and developmental cell growth were turned on while, in AKR/J mice, genes involved in sensory perception, cognition, olfactory transduction, G-protein coupled receptor pathways, inflammatory response, proteolysis, and base excision repair were found to be affected by LDR. We validated LDR-sensitive EGs by qPCR and confirmed specific upregulation of S100a7a, Olfr624, and Gm4868 genes in AKR/J mice whole brain. Therefore, our data provide the first report of genetic changes regulated by LDR in the mouse whole brain, which may affect several aspects of brain function.

• 인지과학
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• 제21권2호
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• pp.309-338
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• 2010

본 논문에서는 사지가 마비되어 신체를 움직이지 못하지만 뇌의 기능은 살아있는 장애인들을 위하여, 생각만으로 외부의 장치를 제어할 수 있도록 하는 뇌-컴퓨터 인터페이스(BCI: Brain-Computer Interface) 기술을 연구하였다. 신경생리학 분야에서의 연구 결과에 의하면, 신체를 움직이는 상상을 할 경우, 뇌의 운동/감각 피질 영역에서는 $\beta$파(14-26 Hz)와 $\mu$파(8-12 Hz)가 억제/증가되는 ERD/ERS(Event-Related Desynchronization / Synchronization) 현상이 발생한다고 알려져 있다. 본 연구에서는 이를 기반으로 혀, 발, 왼손, 오른손의 동작 상상을 자극으로 이용하여 변화하는 뇌 신호 패턴을 실시간으로 분석하여 피험자의 생각을 읽을 수 있도록 하였으며, 상 하 좌 우의 네 방향으로 이동할 수 있도록 하는 마우스 제어 인터페이스를 구현하였다. 동작 상상 시 발생하는 뇌 신경 활동의 변화를 관측하기 위해서 뇌에 손상을 주지 않으면서도 높은 시간 해상도로 측정이 가능한 비침습적 뇌전도(EEG: ElectroEncephaloGraphy)를 이용하였다. 그러나 뇌전도 신호는 특성상 신호의 크기가 미약하고, 잡음의 영향을 많아 분석이 어렵다. 따라서 이를 극복하기 위해 통계적 방법을 기반으로 한 기계학습 기법인 CSP(Common Spatial Pattern)와 선형판별 분석(Linear Discriminant Analysis)을 이용하여 서로 다른 동작 상상에 의해 발생하는 뇌 신호들 간의 분산이 최대가 되도록 신호를 변환하여 인식 성능을 높일 수 있었다. 또한 분석된 뇌 신호의 시각화를 통해, 기존에 알려진 뇌의 해부학적, 신경생리학적 지식과 일치하는 ERD/ERS 현상이 발생하는 것을 확인할 수 있었다.

• The Korean Journal of Physiology and Pharmacology
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• 제17권1호
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• pp.89-97
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• 2013

Developing an animal model for a specific disease is very important in the understanding of the underlying mechanism of the disease and allows testing of newly developed new drugs before human application. However, which of the plethora of experimental animal species to use in model development can be perplexing. Administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) is a very well known method to induce the symptoms of Parkinson's disease in mice. But, there is very limited information about the different sensitivities to MPTP among mouse strains. Here, we tested three different mouse strains (C57BL/6, Balb-C, and ICR) as a Parkinsonian model by repeated MPTP injections. In addition to behavioral analysis, endogenous levels of dopamine and tetrahydrobiopterin in mice brain regions, such as striatum, substantia nigra, and hippocampus were directly quantified by liquid chromatography-tandem mass spectrometry. Repeated administrations of MPTP significantly affected the moving distances and rearing frequencies in all three mouse strains. The endogenous dopamine concentrations and expression levels of tyrosine hydroxylase were significantly decreased after the repeated injections, but tetrahydrobiopterin did not change in analyzed brain regions. However, susceptibilities of the mice to MPTP were differed based on the degree of behavioral change, dopamine concentration in brain regions, and expression levels of tyrosine hydroxylase, with C57BL/6 and Balb-C mice being more sensitive to the dopaminergic neuronal toxicity of MPTP than ICR mice.