• 대한수의학회지
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• 제39권1호
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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.

• 재활치료과학
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• 제6권1호
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• pp.35-43
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• 2017

목적 : 양측성 상지 활동의 대칭적, 비대칭적 양측성 상지훈련이 상지기능회복에 미치는 영향을 알아보고자 하였다. 연구방법 : 원주에 소재한 ${\bigcirc}{\bigcirc}$병원의 연구 뇌졸중 환자 15명을 무작위로 대칭적 움직임훈련 그룹과 비대칭적 움직임 훈련 그룹으로 나누었다. 중재는 하루 30분, 주5회, 4주 동안, 총 20회기를 받았다. 결과 : 양측 상지의 실제 사용량은 대칭적 움직임 훈련은 건측, 환측 모두 유의한 변화를 보였으며, 비대칭 움직임 훈련도 환측에서 유의한 변화를 보였다. 또한 환측에서 그룹 간 유의한 변화차이가 있었다. 두 훈련 그룹 모두 수행도와 만족도, 상지기능 변화는 그룹 내 유의미한 변화가 있었지만 그룹 간 차이는 없었다. 결론 : 대칭적 움직임 훈련은 비대칭 움직임 훈련보다 대칭적 움직임은 비대칭적 움직임 보다 운동수행에서의 향상을 보였지만, 보다 명확한 차이를 얻기 위해서는 fMRI와 같은 뇌신경학적 평가도구를 사용하는 것이 필요할 것이라 판단되며, 보다 명확한 훈련 프로토콜이 필요하고, 보다 많은 뇌졸중 환자를 대상으로 한 후속연구의 필요성이 제시된다.

• 한국임상수의학회지
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• 제28권3호
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• pp.323-327
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• 2011

8개월령, 수컷 진도개가 오른쪽 후지 파행으로 의뢰되었다. 이 개는 방사선 검사를 통하여 오른쪽 대퇴골의 단순 골절로 진단되었다. 대퇴골절의 수술적 교정 이후, 술 후 진통제로 합성 아편계 유사 약물인 트라마돌이 정맥 내 주사로 투여되었다. 트라마돌의 투여 직후 발작이 시작되었다. 집중적인 환자 관리에도 불구하고 투여 약 17시간 후 이 개는 폐사하였다. 폐사를 하게 된 원인과 관련하여 트라마돌의 투여에 의한 발작이 연관되어 있을 것으로 추측할 수 있었다. 부검을 실시한 결과 조직병리학적 분석에 따라 본 환자는 괴사성 수막뇌염(NME)으로 진단되었다. 괴사성 수막뇌염을 가진 개에서 트라마돌의 투여가 폐사를 일으킨 발작의 유발과 관련되어 있을 것으로 생각되었다. 본 증례를 통해 트라마돌이 통증 관리에 있어 안전하고 효과적인 약물로 알려져 있으나 뇌염, 뇌수두증, 뇌병증 등의 신경계질환이 있는 환자에서는 주의 깊게 사용되어야 한다는 것을 알 수 있었다.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2000년도 International Meeting 2000
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• pp.23-36
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• 2000

Japanese encephalitis virus (JEV) is the causative agent of a mosquito-borne encephalitis and is transmitted to human via persistently infected mosquito vectors. Although the virus is known to cause only acute infection, there were reports that showed neurological sequelae, latent infection in peripheral mononuclear cells, and recurrence of the disease after acute encephalitis. Innate resistance of certain cell lines, abnormal SN1 expression of the virus, and anti-apoptotic effect of cullular bcl-2 have been suggested as probable causes of JEV persistence even in the absence of defective interfering (DI) particles. Although possible involvement of DI particles in JEV persistence was suggested, neither has a direct evidence for DI presence nor its molecular characterization been made. Two questions asked in this study are whether the DI virus plays any role in JEV persistent infection if it is associated with and what type of change(s) can be made in persistently infected cells to avoid apoptosis even with the continuous virus replication, DI-free standard stock of JEV was infected in BHK-21, Vero, and SW13 cells and serial high multiplicity passages were performed in order to generate DI particles. There different-sized DI RNA species which were defective in both structural and nonstructural protein coding genes. Rescued ORFs of the DI genome maintained in-frame and the presence of replicative intermediate or replicative form RNA of the DI particles confirmed their replication competence. On the other hand, several clones with JEV persistent infection were established from the cells survived acute infections during the passages. Timing of the DI virus generation during the passages seemed coincide to the appearance of persistently infected cells. The DI RNAs were identified in most of persistently infected cells and were observed throughout the cell maintenance. One of the cloned cell line maintained the viral persistence without DI RNA coreplication. The cells with viral persistence released the reduced but continuous infectious JEV particle for up to 9 months and were refractory to homologous virus superinfection but not to heterologous challenges. Unlike the cells with acute infection these cells were devoid of characteristic DNA fragmentation and JEV-induced apoptosis with or without homologous superinfection. Therefore, the DI RNA generated during JEV undiluted serial passage on mammalian cells was shown to be biologically active and it seemed to be responsible, at least in part, for the establishment and maintenance of the JEV persistence in mammalian cells. Viral persistence without DI RNA coreplication, as in one of the cell clones, supports that JEV persistent infection could be maintained with or without the presence of DI particles. In addition, the fact that the cells with JEV persistence were resistant against homologous virus superinfection, but not against heterologous one, suggests that different viruses have their own and independent pathway for cytopathogenesis even if viral cytopathic effect could be converged to an apoptosis after all.

• Investigative Magnetic Resonance Imaging
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• 제19권4호
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• pp.231-236
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• 2015

A 17-year-old girl presented with complaints of headache and decreasing vision of one month's duration, without any history of fever, weight loss, or any evidence of an immuno-compromised state. Her neurological examination was normal, except for papilledema. Laboratory investigations were within normal limits, except for a slightly increased Erythrocyte Sedimentation Rate (ESR). Non-contrast computerized tomography of her head revealed complex mass in left frontal lobe with a concentric, slightly hyperdense, thickened wall, and moderate perilesional edema with mass effect. Differential diagnoses considered in this case were pilocytic astrocytoma, metastasis and abscess. Magnetic resonance imaging (MRI) obtained in 3.0 Tesla (3.0T) scanner revealed a lobulated outline cystic mass in the left frontal lobe with two concentric layers of T2 hypointense wall, with T2 hyperintensity between the concentric ring. Moderate perilesional edema and mass effect were seen. Post gadolinium study showed a markedly enhancing irregular wall with some enhancing nodular solid component. No restricted diffusion was seen in this mass in diffusion weighted imaging (DWI). Magnetic resonance spectroscopy (MRS) showed increased lactate and lipid peaks in the central part of this mass, although some areas at the wall and perilesional T2 hyperintensity showed an increased choline peak without significant decrease in N-acetylaspartate (NAA) level. Arterial spin labelling (ASL) and dynamic susceptibility contrast (DSC) enhanced perfusion study showed decrease in relative cerebral blood volume at this region. These features in MRI were suggestive of brain abscess. The patient underwent craniotomy with excision of a grayish nodular lesion. Abundant acid fast bacilli (AFB) in acid fast staining, and epithelioid cell granulomas, caseation necrosis and Langhans giant cells in histopathology, were conclusive of tubercular abscess. Tubercular brain abscess is a rare manifestation that simulates malignancy and cause diagnostic dilemma. MRI along with MRS and magnetic resonance perfusion studies, are powerful tools to differentiate lesions in such equivocal cases.

• 한국식품위생안전성학회지
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• 제29권2호
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• pp.85-91
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• 2014

Deoxynivalenol (DON) and related trichothecene mycotoxins are extensively distributed in the cereal-based food and feed stuffs worldwide. Recent climate changes and global grain trade increased chance of exposure to more DON and related toxic metabolites in poorly managed production systems. Monitoring the biological and environmental exposures to the toxins are crucial in protecting human and animals from toxicities of the hazardous contaminants in food or feeds. Exposure biomarkers including urine DON itself are prone to shift to less harmful metabolites by intestinal microbiota and liver metabolic enzymes. De-epoxyfication of DON by gut microbes such as Eubacterium strain BBSH 797 and Eubacterium sp. DSM 11798 leads to more fecal secretion of DOM-1. By contrast, most of plant-derived DON-glucoside is also easily catabolized to free DON by gut microbes, which produces more burden to body. Phase 2 hepatic metabolism also contributes to the glucuronidation of DON, which can be useful urine biomarkers. However, chemical modification could be very typical depending on the anthropologic or genetic background, luminal bacteria, and hepatic metabolic enzyme susceptibility to the toxins in the diet. After toxin exposure, effect biomarkers are also important in estimating the linkage and mechanisms of foodborne diseases in human and animal population. Most prominent adverse effects are demonstrated in the DON-induced immunological and behavioral disorders. For instance, acutely elevated interleukin-8 from insulted gut exposed to dietaty DON is a dominant clinical biomarker in human and animals. Moreover, subchronic exposure to the toxins is associated with high levels of serum IgA, a biological mediator of IgA nephritis. In particular, anorexia monitoring using mouse models are recently developed to monitor the biological activities of DON-induced feed refusal. It is also mechanistically linked to alteration of serotoin and peptide YY, which are promising biomarkers of neurological disorders by the toxins. As animal-alternative biomonitoring, huamn enterocyte-based assay has been developed and more realistic gut mimetic models would be useful in monitoring the effect biomarkers in resposne to toxic contaminants in the future investigations.

• 생명과학회지
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• 제29권5호
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• pp.564-569
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• 2019

최근 알코올 소비량이 증가함에 따라 과량의 에탄올을 섭취하는 경우 또한 늘어나고 있다. 이런 과도한 에탄올 섭취는 ${\gamma}$-aminobutyric acid (GABA) 수용체의 활성화와 glutamate 수용체의 활성 억제를 통해 신경계를 교란시켜 단기 기억 형성을 방해 한다. 알코올에 의한 인지기능의 저하는 알코올성 black out을 유도할 수 있으며, 반복될 경우 알코올성 치매로 이어질 수 있기 때문에 black out을 예방하는 치료제의 개발이 필요하다. 따라서 본 연구자는 해당 연구를 통하여 Cassia obtusifolia seeds 에탄올 추출물(COE)이 가진 black out 예방제로써의 가능성을 평가하였다. 본 연구에서는 에탄올에 의해 유도된 기억 장애에 대한 COE의 효과를 확인하였다. 실험 동물의 기억력을 측정하기 위하여 수동 회피 실험과 Y자 미로 실험을 수행하였고, 마우스 해마 절편을 사용하여 에탄올이 기억의 형성과 관련하여 장기 강화(long term potentiation; LTP)에 어떠한 영향을 끼치는지 전기생리학을 통해 확인하였다. 또한 ${\alpha}$-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid 수용체 길항제인 NBQX ($50{\mu}M$)를 사용하여 에탄올에 의한 인지기능 장애와 관련이 있다고 알려진 N-Methyl-D-aspartate (NMDA) 매개 field 흥분성 시냅스 후 전위를 측정하였다. 결과적으로, COE는 에탄올에 의한 기억력의 손상을 방지하였고, 해마 절편에서 에탄올에 의해 감소된 LTP와 NMDA 매개 흥분성 시냅스 후 전위를 대조군과 비슷한 수준까지 회복시켰다.

• 재활치료과학
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• 제8권2호
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• pp.67-78
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• 2019

목적 : 본 연구에서는 말소리장애 아동과 일반 아동을 대상으로 어휘인출 시 단순 손동작(hand tapping)을 반복하게 하는 것이 조음정확도와 유창성에 어떠한 영향을 미치는지에 대해 알아보았다. 손동작을 반복하면서 어휘를 산출하는 것은 주의를 분산시키는 이중과제에 해당하기 때문에, 주의력 저하가 보고된 말소리장애 아동의 경우 일반 아동과 다른 행동 양상을 보이는지를 파악하고자 하였다. 연구방법 : 4, 5, 6세의 말소리장애 아동 15명과 일반 아동 15명이 본 연구에 참여하였다. 조음복잡성이 높은 어휘와 낮은 어휘를 각각 15개씩, 총 30개를 선정하여, 이에 대한 대면이름대기 과제를 실시하였다. 첫 번째 실험조건에서는 단순 손동작을 반복하지 않고, 두 번째 실험조건에서는 손바닥으로 책상을 두드리면서 그림 이름을 말하도록 하였다. 대상자의 반응에 대해 자음정확도, 비유창성 정도, 정확성 변화와 유창성 변화의 상관관계를 측정하여, 두 실험조건에 따른 두 집단 간 수행력을 비교하였다. 결과 : 첫째, 말소리장애 집단과 일반 집단 모두 손동작 반복 과제와 손동작 비반복 과제 간 자음정확도에는 유의한 차이가 없었다. 둘째, 일반 집단은 손동작 반복 과제에서 비유창성이 유의하게 증가하였으나, 말소리장애 집단은 차이가 없었다. 셋째 손동작 반복에 따른 자음정확도 변화와 비유창성 변화는 일반집단의 경우 유의한 양의 상관관계가 있었으나 말소리장애 집단은 아무런 상관을 보이지 않았다. 결론 : 본 연구에서 주의력 분산을 위해 사용한 단순 손동작 반복은 결과적으로 집단에 따라 대상자의 목표행동에 방해가 될 수도, 혹은 그 반대로 도움이 될 수도 있었다. 어휘인출에 대한 손동작 반복의 영향이 두 집단 간 다른 양상으로 나타난 만큼 이에 대한 심층적 논의가 필요할 것이다.

• Journal of Korean Neurosurgical Society
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• 제64권1호
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• pp.78-87
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• 2021

Objective : Intraoperative neurophysiological monitoring (IONM) has been widely used during spine surgery to reduce or prevent neurologic deficits, however, its application to the surgical management for cervical myelopathy remains controversial. This study aimed to assess the success rate of IONM in patients with cervical myelopathy and to investigate the factors associated with successful baseline monitoring and the effect of increasing the stimulation intensity by focusing on motor evoked potentials (MEPs). Methods : The data of 88 patients who underwent surgery for cervical myelopathy with IONM between January 2016 and June 2018 were retrospectively reviewed. The success rate of baseline MEP monitoring at the initial stimulation of 400 V was investigated. In unmonitorable cases, the stimulation intensity was increased to 999 V, and the success rate final MEP monitoring was reinvestigated. In addition, factors related to the success rate of baseline MEP monitoring were investigated using independent t-test, Wilcoxon rank-sum test, chi-squared test, and Fisher's exact probability test for statistical analysis. The factors included age, sex, body mass index, diabetes mellitus, smoking history, symptom duration, Torg-Pavlov ratio, space available for the cord (SAC), cord compression ratio (CCR), intramedullary increased signal intensity (SI) on magnetic resonance imaging, SI length, SI ratio, the Medical Research Council (MRC) grade, the preoperative modified Nurick grade and Japanese Orthopedic Association (JOA) score. Results : The overall success rate for reliable MEP response was 52.3% after increasing the stimulation intensity. No complications were observed to be associated with increased intensity. The factors related to the success rate of final MEP monitoring were found to be SAC (p<0.001), CCR (p<0.001), MRC grade (p<0.001), preoperative modified Nurick grade (p<0.001), and JOA score (p<0.001). The cut-off score for successful MEP monitoring was 5.67 mm for SAC, 47.33% for the CCR, 3 points for MRC grade, 2 points for the modified Nurick grade, and 12 points for the JOA score. Conclusion : Increasing the stimulation intensity could significantly improve the success rate of baseline MEP monitoring for unmonitorable cases at the initial stimulation in cervical myelopathy. In particular, the SAC, CCR, MRC grade, preoperative Nurick grade and JOA score may be considered as the more important related factors associated with the success rate of MEP monitoring. Therefore, the degree of preoperative neurological functional deficits and the presence of spinal cord compression on imaging could be used as new detailed criteria for the application of IONM in patients with cervical myelopathy.

• Journal of Ginseng Research
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• 제46권4호
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• pp.515-525
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• 2022

Background: The incidence of ischemic cerebrovascular disease is increasing in recent years and has been one of the leading causes of neurological dysfunction and death. Ginsenoside Rg1 has been found to protect against neuronal damage in many neurodegenerative diseases. However, the effect and mechanism by which Rg1 protects against cerebral ischemia-reperfusion injury (CIRI) are not fully understood. Here, we report the neuroprotective effects of Rg1 treatment on CIRI and its possible mechanisms in mice. Methods: A bilateral common carotid artery ligation was used to establish a chronic CIRI model in mice. HT22 cells were treated with Rg1 after OGD/R to study its effect on [Ca²⁺]_i. The open-field test and poleclimbing experiment were used to detect behavioral injury. The laser speckle blood flowmeter was used to measure brain blood flow. The Nissl and H&E staining were used to examine the neuronal damage. The Western blotting was used to examine MAP2, PSD95, Tau, p-Tau, NOX2, PLC, p-PLC, CN, NFAT1, and NLRP1 expression. Calcium imaging was used to test the level of [Ca²⁺]_i. Results: Rg1 treatment significantly improved cerebral blood flow, locomotion, and limb coordination, reduced ROS production, increased MAP2 and PSD95 expression, and decreased p-Tau, NOX2, p-PLC, CN, NFAT1, and NLRP1 expression. Calcium imaging results showed that Rg1 could inhibit calcium overload and resist the imbalance of calcium homeostasis after OGD/R in HT22 cells. Conclusion: Rg1 plays a neuroprotective role in attenuating CIRI by inhibiting oxidative stress, calcium overload, and neuroinflammation.