• 제목/요약/키워드: Brain- based Research

검색결과 682건 처리시간 0.03초

완전삽입형 인공망막 구현을 위한 인공망막모듈 개발 (Development of Retinal Prosthesis Module for Fully Implantable Retinal Prosthesis)

  • 이강욱;카이호 요시유키;후쿠시마 타카후미;타나까 테츠;고야나기 미쯔마사
    • 대한의용생체공학회:의공학회지
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    • 제31권4호
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    • pp.292-301
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    • 2010
  • To restore visual sensation of blind patients, we have proposed a fully implantable retinal prosthesis comprising an three dimensionally (3D) stacked retinal chip for transforming optical signal to electrical signal, a flexible cable with stimulus electrode array for stimulating retina cells, and coupling coils for power transmission. The 3D stacked retinal chip is consisted of several LSI chips such as photodetector, signal processing circuit, and stimulus current generator. They are vertically stacked and electrically connected using 3D integration technology. Our retinal prosthesis has a small size and lightweight with high resolution, therefore it could increase the patients` quality of life (QOL). For realizing the fully implantable retinal prosthesis, we developed a retinal prosthesis module comprising a retinal prosthesis chip and a flexible cable with stimulus electrode array for generating optimal stimulus current. In this study, we used a 2D retinal chip as a prototype retinal prosthesis chip. We fabricated the polymide-based flexible cable of $20{\mu}m$ thickness where 16 channels Pt stimulus electrode array was formed in the cable. Pt electrode has an impedance of $9.9k{\Omega}$ at 400Hz frequency. The retinal prosthesis chip was mounted on the flexible cable by an epoxy and electrically connected by Au wire. The retinal prosthesis chip was cappted by a silicone to pretect from corrosive environments in an eyeball. Then, the fabricated retinal prosthesis module was implanted into an eyeball of a rabbit. We successfully recorded electrically evoked potential (EEP) elicited from the rabbit brain by the current stimulation supplied from the implanted retinal prosthesis module. EEP amplitude was increased linearly with illumination intensity and irradiation time of incident light. The retinal prosthesis chip was well functioned after implanting into the eyeball of the rabbit.

Functional characterization of $P_{2X}/P_{2Y}$ receptor in isolated swine renal artery

  • Kim, Joo-heon;Jeon, Je-cheol;Lee, Sang-kil;Lee, Su-jin;Lee, Younggeon;Won, Jinyoung;Kang, Jae seon;Hong, Yonggeun
    • 대한수의학회지
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    • 제47권4호
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    • pp.371-378
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    • 2007
  • To understand the role of $PM_{2X}/P_{2Y}$ receptor in cortex region of kidney and renal artery, molecular and functional analysis of $PM_{2X}/P_{2Y}$ receptor by pharmacophysiological skill in conventional swine tissues were performed. In functional analysis of $P_{2Y}$ receptor for vascular relaxation, 2-methylthio adenosine triphosphate, a strong agonist of $P_{2Y}$ receptor, induced relaxation of noradrenaline (NA)-precontracted renal artery in a dose-dependent manner. Strikingly, relaxative effect of ATP, 2-msATP, agonists of $P_{2Y}$ receptor, abolished by treatment of reactive blue 2, a putative $P_{2Y}$ receptor antagonist. In contrast, no significant differences of gene encoding $PM_{2X}/P_{2Y}$ and protein expression in immortalized suprachiasmatic nucleus from brain, primary isolated vascular smooth muscle cells from renal artery of pigs and HEK293 from human embryonic kidney under with/without adenosine triphosphate were observed. Taken together, the relationship between molecular and functional characteristic of $PM_{2X}/P_{2Y}$ receptors in conventional pig should be considered that they are another important factor which regulate the kidney function in swine. Based on this study, we propose the purinergic receptor as well as adrenergic and cholinergic receptors is an essential component of the renal homeostasis.

Identification of intracerebral hematoma using ultrasonography in a dog

  • Jung, Dong-In;Park, Chul;Kang, Byeong-Teck;Yoo, Jong-Hyun;Kim, Ju-Won;Kim, Ha-Jung;Lim, Chae-Young;Lee, So-Young;GU, Su-Hyun;Heo, Ra-Young;Jeon, Hyo-Won;Kim, Jung-Hyun;Eom, Ki-Dong;Park, Jong-Im;Park, Hee-Myung
    • 대한수의학회지
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    • 제47권1호
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    • pp.127-129
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    • 2007
  • A 3-month-old male Maltese dog was presented with generalized trembling, ataxia, and seizure.The patient had traumatic injury on history takings. Physical examination revealed dome shaped craniumwith open fontanelle, nasal hemorrhage, and blepharoedema with hemorhage on the left side. On serumbiochemical profiles, creatine phosphokinase was severely elevated. There was no remarkable findingon radiography. Ultrasound images of brain were obtained via a persistence bregmatic fontanelle, andbilateraly dilated lateral ventricles with a hyperechoic mass on the left temporal lobe were detected.Based on clinical signs, history, physical examination, laboratory findings, and ultrasonographic findings,we suspected this intracranial mass to intracerebral hematoma induced by head trauma. Methylprednisoloneh after initial diagnosis. We performed necropsy and confirmed intracerebral hematoma. This case reportdescribes the identification of intracerebral hematoma using ultrasonography.

Expression of BrD1, a Plant Defensin from Brassica rapa, Confers Resistance against Brown Planthopper (Nilaparvata lugens) in Transgenic Rices

  • Choi, Man-Soo;Kim, Yul-Ho;Park, Hyang-Mi;Seo, Bo-Yoon;Jung, Jin-Kyo;Kim, Sun-Tae;Kim, Min-Chul;Shin, Dong-Bum;Yun, Hong-Tai;Choi, Im-Soo;Kim, Chung-Kon;Lee, Jang-Yong
    • Molecules and Cells
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    • 제28권2호
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    • pp.131-137
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    • 2009
  • Plant defensins are small (5-10 kDa) basic peptides thought to be an important component of the defense pathway against fungal and/or bacterial pathogens. To understand the role of plant defensins in protecting plants against the brown planthopper, a type of insect herbivore, we isolated the Brassica rapa Defensin 1 (BrD1) gene and introduced it into rice (Oryza sativa L.) to produce stable transgenic plants. The BrD1 protein is homologous to other plant defensins and contains both an N-terminal endoplasmic reticulum signal sequence and a defensin domain, which are highly conserved in all plant defensins. Based on a phylogenetic analysis of the defensin domain of various plant defensins, we established that BrD1 belongs to a distinct subgroup of plant defensins. Relative to the wild type, transgenic rices expressing BrD1 exhibit strong resistance to brown planthopper nymphs and female adults. These results suggest that BrD1 exhibits insecticidal activity, and might be useful for developing cereal crop plants resistant to sap-sucking insects, such as the brown planthopper.

나노 은을 이용한 전자파 차폐 직물이 뇌파에 미치는 영향 (A Study on the Effects of Electroencephalogram of Blocking Electromagnetic Wave Materials by useing the Nano Silver)

  • 이수정;이태일
    • 한국의류산업학회지
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    • 제6권6호
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    • pp.810-814
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    • 2004
  • This study is one of the fundamental researches for the development of future smart clothing and textile products using silver(Ag) nano powder. Our study was focused on the blocking or insulating effects of nano-processed textiles from electromagnetic waves. Also, for the surveying of the actual effect to human body, we measure the variation of electroencephalogram which is an indication of human physical symptoms. Among various textiles in this experiment, nano silver processed case has shown the best blocking performance from the electromagnetic waves, which decreases depending on the distance. As a reference model of working environment, we setup the visual stimuli object on the computer that is a source of electromagnetic wave. The power spectrum distribution and the incidence of electroencephalogram was measured. The analysed data has shown that, with nano-processed textiles, ${\beta}$ wave does not appear very often where ${\beta}$ wave appears only to illustrate the stable states of human's body. However, as for the materials without nano processing, the ratio of ${\gamma}$ waves in the total level of electroencephalogram becomes higher in spite of short exposure to visual stimuli in work environment, which shows that the worker becomes stressed. The ${\beta}$ wave electroencephalogram of all materials is drawn in calcarine fissure of occipital lobe to show the convergent distribution, and stronger with block-processed Nano Silver Silk(NSS). The study based on the potential risks of human diseases such as physical fatigue by electromagnetic waves, and has shown that the application of Nano Silver textile for human uses require a proper particle size of it which would not penetrate cellular tissues, and a proper binder and binding treatment for it. However, it is highly required for back-up researches to verify various aspects in applying nano silver to textile products.

Identification of Three Competitive Inhibitors for Membrane­Associated, $Mg^{2+}-Dependent$ and Neutral 60 kDa Sphingomyelinase Activity

  • Kim Seok Kyun;Jung Sang Mi;Ahn Kyong Hoon;Jeon Hyung Jun;Lee Dong Hun;Jung Kwang Mook;Jung Sung Yun;Kim Dae Kyong
    • Archives of Pharmacal Research
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    • 제28권8호
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    • pp.923-929
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    • 2005
  • Methanol extracts of domestic plants of Korea were evaluated as a potential inhibitor of neutral pH optimum and membrane-associated 60 kDa sphingomyelinase (N-SMase) activity. In this study, we partially purified N-SMase from bovine brain membranes using ammonium sulfate. It was purified approximately 163-fold by the sequential use of DE52, Butyl-Toyopearl, DEAE-Cellulose, and Phenyl-5PW column chromatographies. The purified N-SMase activity was assayed in the presence of the plant extracts of three hundreds species. Based on the in vitro assay, three plant extracts significantly inhibited the N-SMase activity in a time- and concentration-dependent manner. To further examine the inhibitory pattern, a Dixon plot was constructed for each of the plant extracts. The extracts of Abies nephrolepis, Acer tegmentosum, and Ginkgo biloba revealed a competitive inhibition with the inhibition constant (Ki) of $11.9 {\mu}g/mL,\;9.4{\mu}g/mL,\;and\;12.9{\mu}g/mL$, respectively. These extracts also inhibited in a dose-dependent manner the production of ceramide induced by serum deprivation in human neuroblastoma cell line SH-SY5Y.

두부충동 검사 (Head Thrust Test)

  • 최광동;오선영;김지수
    • Annals of Clinical Neurophysiology
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    • 제8권1호
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    • pp.1-5
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    • 2006
  • The head thrust maneuver is a simple bedside test of the higher frequency vestibulo-ocular reflex, which is based on Ewald's second law. It is performed by grasping the patient's head and applying a brief, small-amplitude, high-acceleration head turn, first to one side and then to the other. The patient fixates on the examiner's nose and the examiner watches for corrective rapid eye movements (saccades), which are a sign of decreased vestibular response. The "catch-up" saccades after a head thrust in one direction indicate a peripheral vestibular lesion on that side (in the labyrinth or the $8^{th}$ nerve including the root's entry zone in the brain stem). An individual pair of vertical semicircular canals can also be stimulated by turning the head to the right or left by $45^{\circ}$ and then by rotating the head in the pitch plane relative to the body. Recent studies have suggested that assessment of individual semicircular canal function by head thrust test may provide useful information for anatomical and functional details of a variety of peripheral vestibulopathies and for predicting the prognosis of vestibular neuritis. In central vestibulopathy, the head thrust test may also be valuable sign to determine dysfunction of the central pathways from individual semicircular canals and its role for the development of diverse central nystagmus.

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CGE와 TRFGE 기법으로 얻은 뇌기능 영상에서 혈류효과와 자화율 효과의 해석 (Analysis of Inflow and Susceptibility Effects in fMRI Obtained by CGE and TRFGE Techniques)

  • 노용만;정순철;조장희
    • 대한의용생체공학회:의공학회지
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    • 제16권4호
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    • pp.431-438
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    • 1995
  • Tailored RF 경사자계 영상법을 이용하여 혈류효과를 배제한 자화율 효과만의 뇌기능 영상을 얻을수 있었다. 일반적인 RF를 이용한 경사자계 뇌기능 영상법은 빠른 경사자계 영상법으로 인해 정맥뿐만 아니라 동맥에서의 혈류효과와 $T2^{*}$ 효과가 합쳐진 영상을 얻게되는 반면, tailored RF를 이용한 경사자계 영상법은 산소소모와 관계된 자화율 변화에 의한 뇌기능 영상을 얻을 수 있었다. 본 논문에서 tailored RF를 이용하여 뇌기능 영상에서 자화율효과와 혈류효과를 명확히 구분할 수 있음을 보였다. 그리고 실험결과로 얻은 신호는 충분히 크고 산소 소모의 변화를 보다 더 정확히 표현하므로 지금까지 다른 경사자계 영상법으로는 어려웠던 뇌기능 영상에서 정량화된 산소 신진대사 연구의 가능성을 보여주었다.

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아동의 발열에 대한 부모의 인식 및 대처방법 (Parent's Knowledge and Cope of Their Child Fever)

  • 정용선;이용화;박기원;이자형
    • 부모자녀건강학회지
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    • 제11권2호
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    • pp.105-114
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    • 2008
  • Purpose: The purpose of this study was to identify parent's knowledge and cope with their child's fever. Confirmed data provide source and it based on parent's education program and nursing intervention. Method: The research design was a descriptive study by questionnaire. Data were collected from July, 16, 2007 to August, 6, 2007. A total 165 parents who visited the children's hospital in Gwangju. Data were analysed using the SPSS WIN 12.0 program. Results: The results of this study were as follows: 1. Fever was major cause which to visit hospital among children(50.3%). 2. Parents main concerned by child fever were convulsion(52.7%) and brain injury(46.7%). 3. When cause fever most parents checking interval are 30 minutes (38.8%), the most fever management was used antipyretics with tepid water massage(59.4%). 4. Antipyretics used interval was 4hours(56.4%). 5. When visit to hospital by fever, most treatment was antipyretics. 6. The method to get fever information, first by doctor(68.5%), second by family-relative(41.8%) and last by nurse(22.4%). Conclusion: It is necessary to provide information about management of fever. Development and distribution for effective education program for child fever at home are also necessary. Therefore we suggest the education program on the internet.

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Chronic dietary ginseng extract administration ameliorates antioxidant and cholinergic systems in the brains of aged mice

  • Lee, Mi Ra;Ma, Jin Yeul;Sung, Chang Keun
    • Journal of Ginseng Research
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    • 제41권4호
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    • pp.615-619
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    • 2017
  • Background: Black ginseng has a more potent biological activity than non-steamed ginseng. We investigated the effects of long-term intake of dietary black ginseng extract (BG) on antioxidant activity in aged mice. We also compared the effects of BG on cognitive deficits with those of white ginseng extract (WG) and red ginseng extract (RG). Methods: Ten-month-old mice were fed an AIN-93G-based diet containing 10 g/kg (low dose, L) or 30 g/kg (high dose, H) WG powder, RG powder, or BG powder for 24 wk. We measured serum lipids, the activities of antioxidant enzymes, and malondialdehyde levels. Additionally, the protein expression levels of choline acetyltransferase and vesicular acetylcholine transporter, which are presynaptic cholinergic markers in the cortex and hippocampus of the brain, were measured by western blotting. Results: Triglyceride levels were reduced in all the extract-treated mice, except those in the LBG group. High-density lipoprotein cholesterol levels in the HBG group were higher than those in the control group. Total cholesterol levels were reduced in the LBG group. Additionally, glucose levels in the HBG group were significantly reduced by 41.2%. There were lower levels of malondialdehyde in the LBG group than in the control group. Furthermore, glutathione reductase activity increased in the HWG group and the HRG group. The protein expression levels of choline acetyltransferase and vesicular acetylcholine transporter significantly increased in all the ginseng-treated groups. Conclusion: The results suggest that supplementation with the tested ginseng extracts may suppress the cognitive decline associated with aging, via regulation of the cholinergic and antioxidant defense systems.