• The Korean Journal of Physiology and Pharmacology
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• 제15권4호
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• pp.189-194
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• 2011

ATP-sensitive $K^+$ channels ($K_{ATP}$) are major component of preventing ischemia-reperfusion injury. However, there is little information regarding to the expressional difference of $K_{ATP}$ and its function between left and right ventricles. In this study, we measured the lactate dehydrogenase release of rabbit heart slices in vitro and determined the difference of the $K_{ATP}$ expression at the both ventricles by measuring the level of $K_{ATP}$-forming Kir6.2 (OcKir6.2) mRNA using in situ hybridization. The hearts were preconditioned with 15 min hypoxia and reoxygenated for 15 min before a hypoxic period of 60 min, followed by reoxygenation for 180 min. With hypoxic preconditioning (100% $N_2$) with 15 min, left ventricles (LV) showed higher release of LDH comparing with right ventricles (RV). Adding $K_{ATP}$ blocker glibenclamide ($10{\mu}M$) prior to a hypoxic period of 60 min, hypoxic preconditioning effect of RV was more abolished than LV. With in situ hybridization, the optical density of OcKir6.2 was higher in RV. Therefore, we suggest that different $K_{ATP}$ expression between LV and RV is responsible for the different response to hypoxia and hypoxic preconditioning of rabbit hearts.

• 대한수의학회지
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• 제42권3호
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• pp.429-436
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• 2002

Hydrocepbalus may be an acquired or a congenital condition. We have studied the macroscopic and microscopic changes in the hydrocephalus of an inbred Sprague-Dawley rat at postnatal week 8. The animal suspected with the hydrocephalus showed clinical syndromes such as depression, severe ataxia, eye abnormalities, dome-shaped head, and persistent fontanelle. With the postmortem examination, the suspected animal was clearly revealed as a severe internal hydrocephalus. In this animal, severe ventriculomegaly was limited to the third and lateral ventricles, and cortical thining was most apparent in the parieto-occipital region. With the routine histological examination, brain tissue showed aqueductal obstruction, thinning of the cerebral cortex, severe ependymal damage, subependymal edema, damage of choroid plexus of fourth ventricle, enlarged cortical vessels, and expanded ventricles. Aqueductal obstruction was observed with the appearance of simple stenosis at the level of rostral colliculus. Subsequently, the other structures of brain such as septal nucleus, caudate nucleus, and hippocampus etc. were abnormally reconstructed by hydrocephalus. This study suggests that the hydrocephalus can be taken place by primary aqueductal obstruction and this type of hydrocephalus is classified as uncommunicating type. Though the mechanism of aqueductal obstruction is not clear, the morphological studies of this case may be helpful for the further study of hydrocephalus.

• Journal of Korean Neurosurgical Society
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• 제57권1호
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• pp.68-71
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• 2015

We report a case of non communicating hydrocephalus due to membranous obstruction of Magendie's foramen. A 37-year-old woman presented with intracranial hypertension symptoms caused by the occlusion of Magendie's foramen by a membrane probably due to arachnoiditis. As far as the patient's past medical history is concerned, an Epstein-Barr virus infectious mononucleosis was described. Fundoscopic examination revealed bilateral papilledema. Brain magnetic resonance imaging demonstrated a significant ventricular dilatation of all ventricles and turbulent flow of cerebelospinal fluid (CSF) in the fourth ventricle as well as back flow of CSF through the Monro's foramen to the lateral ventricles. The patient underwent a suboccipital craniotomy with C1 laminectomy. An occlusion of Magendie's foramen by a thickened membrane was recognized and it was incised and removed. We confirm the existence of hydrocephalus caused by fourth ventricle outflow obstruction by a membrane. The nature of this rare entity is difficult to demonstrate because of the complex morphology of the fourth ventricle. Treatment with surgical exploration and incision of the thickened membrane proved to be a reliable method of treatment without the necessity of endoscopic third ventriculostomy or catheter placement.

• 대한의용생체공학회:의공학회지
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• 제38권2호
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• pp.82-88
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• 2017

Enlargement of the lateral ventricles have been identified as a surrogate marker of neurological disorders. Quantitative measure of the lateral ventricle from MRI would enable earlier and more accurate clinical diagnosis in monitoring disease progression. Even though it requires an automated or semi-automated segmentation method for objective quantification, it is difficult to define lateral ventricles due to insufficient contrast and brightness of structural imaging. In this study, we proposed a fully automated lateral ventricle segmentation method based on a graph cuts algorithm combined with atlas-based segmentation and connected component labeling. Initially, initial seeds for graph cuts were defined by atlas-based segmentation (ATS). They were adjusted by partial volume images in order to provide accurate a priori information on graph cuts. A graph cuts algorithm is to finds a global minimum of energy with minimum cut/maximum flow algorithm function on graph. In addition, connected component labeling used to remove false ventricle regions. The proposed method was validated with the well-known tools using the dice similarity index, recall and precision values. The proposed method was significantly higher dice similarity index ($0.860{\pm}0.036$, p < 0.001) and recall ($0.833{\pm}0.037$, p < 0.001) compared with other tools. Therefore, the proposed method yielded a robust and reliable segmentation result.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.126-130
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• 1997

In the development of the totally implantable artificial heart (TAH), the information of the preload condition is important to ind appropriate condition or the automatic control of the heart. Our TAH configuration consists of two artificial ventricles, and brushless DC motor within actuator. The pressure between ventricles could indicate the preload condition during the TAH operation. If we can measure accurately inspite of the noise induced from TAH and environmental condition. We suggested integrating a feedback loop to remove an unexpected DC drift. NPI 19-series Nova sensor was used which could measure pressure in gas and liquid. This method and sensor enabled us to develop the pressure transducer compact so (that) the systems can be implanted with TAH into patient. This system has been verified in vitro and in vivo test. This results showed that the output waveform of this system was stable irrespective of animal condition.

• Molecules and Cells
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• 제38권5호
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• pp.426-431
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• 2015

Odin has been implicated in the downstream signaling pathway of receptor tyrosine kinases, such as the epidermal growth factor and Eph receptors. However, the physiologically relevant function of Odin needs to be further determined. In this study, we used Odin heterozygous mice to analyze the Odin expression pattern; the targeted allele contained a ${\beta}$-geo gene trap vector inserted into the 14t intron of the Odin gene. Interestingly, we found that Odin was exclusively expressed in ependymal cells along the brain ventricles. In particular, Odin was highly expressed in the subcommissural organ, a small ependymal glandular tissue. However, we did not observe any morphological abnormalities in the brain ventricles or ependymal cells of Odin null-mutant mice. We also generated BAC transgenic mice that expressed the PTB-deleted Odin (dPTB) after a floxed GFP-STOP cassette was excised by tissue-specific Cre expression. Strikingly, Odin-dPTB expression played a causative role in the development of the hydrocephalic phenotype, primarily in the midbrain. In addition, Odin-dPTB expression disrupted proper development of the subcommissural organ and interfered with ependymal cell maturation in the cerebral aqueduct. Taken together, our findings strongly suggest that Odin plays a role in the differentiation of ependymal cells during early postnatal brain development.

• Korean Circulation Journal
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• 제48권11호
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• pp.1014-1024
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• 2018

Background and Objectives: Intense exercise (IE) induced myocardial fibrosis (MF) showed contradictory findings in human studies, making the relationship between IE and the development of MF unclear. This study aims to demonstrate exercise induced MF is associated with cardiac damage, and inflammation is essential to the development of exercise induced MF. Methods: Sprague-Dawley rats were submitted to daily 60-minutes treadmill exercise sessions at vigorous or moderate intensity, with 8-, 12-, and 16-week durations; time-matched sedentary rats served as controls. Enzyme-linked immunosorbent assay (ELISA) was used to measure serum cardiac troponin I (cTnI) concentration. After completion of the exercise protocol rats were euthanized. Biventricular morphology, ultrastructure, and collagen deposition were then examined. Protein expression of interleukin $(IL)-1{\beta}$ and monocyte chemotactic protein (MCP)-1 was evaluated in both ventricles. Results: After IE, right but not left ventricle (LV) MF occurred. Serum cTnI levels increased and right ventricular damage was observed at the ultrastructure level in rats that were subjected to long-term IE. Leukocyte infiltration into the right ventricle (RV) rather than LV was observed after long-term IE. Long-term IE also increased protein expression of proinflammation factors including $IL-1{\beta}$ and MCP-1 in the RV. Conclusions: Right ventricular damage induced by long-term IE is pathological and the following inflammatory response is essential to the development of exercise induced MF.

• 대한수의학회지
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• 제28권1호
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• pp.125-135
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• 1988

Attempts of these studies were made to investigate the nonspecific congenital focal accumulation of ectodermal glial cells in the brain of normal piglets. The brain samples were taken from 1-,10-,20-,35-,45- and 70-day-old piglets from a SPF-pig farm and three model pig farms. Occurrences of neuroglial cell foci (NCF) on the brain were observed with light microscope. Appearance degrees of the congenital NCF on 10 to 16 cross section slides per a piglets brain were tentatively designed on a scale from degree+ to ⧻by NCF number: +, less than 20 of NCF number; ⧺, 21-40 of NCF number: ⧻, more than 41 of NCF number. The results obtained were as follows: 1. NCF in the brain were observed mainly on the cerebrum. Regions of higher frequencies on the cerebrum were ordered as subependymal layers of the lateral ventricles, peripheral regions of lateral ventricles in the white matter and some neuron layers under the molecular layer of the gray matter. But NCF were not observed in the cerebellum, pons, medulla oblongata and spinal cords. 2. On the subependymal layers of the lateral ventricles, NCF were observed in 100% of 27 piglets, and appearance degree of ⧻ was observed in 10 piglets(37.0%), ⧺ in 10 piglets(37.0%) and + in 7 Piglets(26.0%) of 27 piglets, respectively. 3. On the white matter of the cerebrum, NCF were observed in 25 piglets(92.6%) of 27 piglets, and appearance degree of ⧻ was observed in 3 piglets(11.1%), ⧺ in 13 piglets(48.2%), + in 9 piglets(33.3%) and - in 2 piglets(7.4%) of 27 piglets, respectively. 4. On the gray matter of the cerebrum, NCF were observed in 21 piglets(77.8%) of 27 piglets, and appearance degree of ⧻ was not observed, appearance degree of ⧺ was observed in 6 piglets(22.2%), + in 15 Piglets(55.6%) and - in 6 piglets(22.2%) of 27 Piglets, respectively. 5. NCF tended to be converged appearance on some regions and tended to be decreased markedly from 35th day after birth, and the shapes of NCF were: global or oval forms crowded by analogous shaped and stained cells in the empty spaces of the brain substrate or on one side of the blood vessels.

• 한국임상수의학회지
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• 제28권1호
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• pp.7-12
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• 2011

본 실험은 서로 다른 세 품종의 소형견인 요크셔테리어, 말티즈, 시쮸 견 각각 30두 에서 컴퓨터단층촬영 검사를 이용하여 뇌실의 크기와 대칭성을 평가하고자 실시되었다. 측뇌실의 크기는 뇌의 시신경수준, 뇌실사이구멍수준, 그리고 악관절 수준에서 뇌실 높이와 너비 그리고 뇌반구의 높이 및 너비가 측정되었다. 뇌실의 크기는 뇌반구의 높이(Bh)와 뇌실의 높이(Vh)의 비율(Vh/Bh)로 평가하였고, 뇌실의 좌우 대칭성은 좌측과 우측의 뇌실 높이의 비(rVh)로 표시하였으며, 각각 정상 (rVh < 1.5), 경미한 확장 (1.5 < rVh < 2), 또는 심한 확장 (2.0 < rVh)로 구분하였다. 실험 결과 임상적으로 유의적이지 않은 뇌실 확장이 세 소형견종에서 흔히 관찰되었다. 그러나, 심각한 뇌실의 비대칭성은 거의 관찰되지 않는 것으로 나타났다. 또한, 측정 결과에 기초하여 약 11 mm의 뇌실 크기가 소형견종에서 정상적으로 나타날 수 있는 뇌실 확장의 상한치로 적용할 수 있을 것으로 생각된다.

• Investigative Magnetic Resonance Imaging
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• 제12권2호
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• pp.170-177
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• 2008

목적 : 순차적인 뇌초음파 검사 후 신생아 중환자실을 퇴원하는 고위험 환아에서 시행한 자기 공명 영상의 유용성을 알아보고자 하였다. 대상 및 방법 : 총 121명의 신생아에서 시행한 412 초음파와 121 자기공명 영상을 후향적으로 분석하여 초음파 검사에서 발견된 뇌병변과 자기 공명영상에서 발견된 병변을 비교하였다. 뇌병변은 배아기질 출혈 및 뇌실 내 출혈, 그 밖의 여러 출혈과 뇌실질 손상을 중심으로 비교 분석하였다. 결과 : 총 242개의 측뇌실 중 30뇌실의 배아기질 출혈 (GMH)을 초음파로 진단하였고 자기공명영상으로 7개의 GMH를 추가로 진단할 수 있었으며 46개 뇌실의 출혈 (IVH)을 추가로 진단하였다. 출혈의 1/2/3/4 등급은 초음파에서 각각 24/8/13/0 뇌실에서 진단하였고 자기공명영상에서 3/49/10/2 뇌실에서 진단하였다. 그 외에 자기공명영상에서 대뇌 출혈 (4예), 소뇌 출혈(4예), 경막하 및 지주막하 출혈 (8예), 미만성 백질 신호강도 변화 (72예), 조직손실이 없는 작은 실질 병변 (4예), 뇌연화증 (2예), 그리고 뇌실확장 (5예)이 추가로 발견되었다. 결론 : 자기공명영상은 초음파 검사 후 두개강내 출혈과 뇌실질 손상을 추가적으로 진단하는 유용한 검사였으며 특히 뇌실 출혈과 백질 손상의 진단에 우수한 반면 배아기질 출혈은 초음파 추적검사가 더 유용할 것으로 생각한다.