파킨슨씨병 환자에서 편측 담창구파괴술의 효과

조우진,이경진,지철,박성찬,박해관,조정기,조경근,나형균,강준기,최창락,Cho, Woo Jin,Lee, Kyung Jin,Ji, Cheul,Park, Sung Chan,Park, Hea Kwan,Jo, Jung Ki,Cho, Kyung Keun,Rha, Hyung Kyun,Kang, Joon Ki,Choi, Chang Rak 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.8

Objectives : For Parkinsonian patients who had not reacted favorably on drug therapy are good candidate for ventroposterolateral pallidotomy, although not curative. We studied these patients after unilateral pallidotomy, to confirm the effectiveness and safety of this procedure. Methods : We evaluated the 17 patients with idiopathic Parkinson's diesease who had undergone unilateral posteroventral pallidotomy. All patients responded to levodopa initially. Mean age was 55 years(38-75years), and mean duration of disease was 9.8 years(3-20years). Pre-and postoperative evaluation at 3 month intervals included Unified Parkinson's Disease Rating scale(UPDRS) scoring, Hoehn and Yahr(H & Y) staging, and neuropsychological examinations. Results : Pallidotomy significantly improved parkinsonian symptom(tremor, rigidity, bradykinesia, dyskinesia, sensory symptom). Nine of 10 patients who showed dyskinesia preoperatively significant improvement. The mean dose of levodopa in 9 patients was lowered. The mean H & Y score and UPDRS score were improved in on and/or off time in 15 patients. Among patients who were not improved, one patient worsened, and the others showed no change. The mean overall UPDRS off score changed from 76 preoperatively to 44(33%) at 6 months and from 70 to 52(25%) at 1 year. Transient surgical morbidity was showen in four patients and included dysarthria, hypotonia and confusion. Conclusion : We conclude that pallidotomy is safe and effective in patients who have levodopa-reponsive parkinsonism with severe symptom fluctuation. Unilateral pallidotomy also considered helpful to ipsilateral symptom. Unilateral pallidotomy can improve all of parkinsonian's symptom and allow to reduce the levodopa medication. Most of patients show satisfactory results.

중성자 보안검색 장치를 위한 신경망 기반의 γ-스펙트럼 분류 방법

최창락(Chang-Rak Choi),김지수(Ji-Soo Kim),김수형(Soo-Hyung Kim),심철무(Cheul-Muu Sim) 한국정보과학회 2007 한국정보과학회 학술발표논문집 Vol.34 No.2C

본 논문은 한국 원자력 연구소 중성자 스펙트럼 패턴을 분류하는 시스템에 신경망(Neural Networks)을 적용하였다. 중성자 스펙트럼 분석시 3개의 신경망을 하나로 결합하여 각 신경망의 인식률을 확인하였다. 신경망1은 폭발물 판별을, 신경망2는 폭발물의 종류를, 신경망3은 비 폭발물 종류를 구별하도록 시스템을 설계하였다. 중성자 스펙트럼을 통해 실험한 결과 신경망1은 83.48%를, 신경망2는 84.6%를, 신경망3은 91.67%의 인식률을 얻어 본 논문에서 제안한 시스템의 우수성을 입증하였다.

중성자 보안검색 장치를 위한 신경망 분류기 비교 연구

최창락 ( Chang-rak Choi ),김지수 ( Ji-soo Kim ),김수형 ( Soo-hyung Kim ),심철무 ( Cheul-muu Sim ) 한국정보처리학회 2007 한국정보처리학회 학술대회논문집 Vol.14 No.2

현재 우리나라는 원자력 발전에 대한 의존도가 매우 높고 그 기술 또한 우수하다. 그러나 중성자 스펙트럼을 사용하여 폭발물 탐지를 위한 시스템 개발 기술은 미흡한 실정이다. 본 논문은 신경망(Neural Networks)을 한국 원자력 연구소 중성자 스펙트럼 패턴을 분류하는 시스템에 적용하였다. 데이터 획득 방법을 달리하여 두 개의 신경망을 구현하였고 그 결과를 분석하여 보았다. 먼저 폭발물에 다량 포함되어 있는 C(Carbon), N(Nitrogen), O(Oxygen) 3개의 물질을 중심으로 중성자 스펙트럼을 분석하였다. 다른 하나는 중성자 스펙트럼을 전체 영역으로 획득한 데이터를 바탕으로 신경망을 구현하여 인식률을 확인하였다. 실험결과 전자의 경우 62.5%의 인식률을, 후자의 경우 신경망은 83.48%의 인식률을 나타내었다.

가정 부문에서의 에너지 소비 실측과 절약 행위에 따른 전기에너지 절감 효과 분석

최창락(Chang Rak, Choi),이영준(Young Jun, Lee),이중호(Jung Ho, Lee),김준혁(Jun Hyeok, Kim),윤종호(Jong Ho, Yoon) 한국생태환경건축학회 2019 한국생태환경건축학회 학술발표대회 논문집 Vol.19 No.2

구리배플을 이용한 수소액화기의 Cold-Box 단열성능에 관한 실험적 연구

김태현(Tae Hyun Kim),최창락(Chang Rak Choi),이정민(Jung Min Lee),한동원(DongWon Han),김서영(Seo Young Kim) 대한설비공학회 2021 대한설비공학회 학술발표대회논문집 Vol.2021 No.6

경막하 수종으로 오인된 중두개와 지주막 낭종을 동반한 대뇌궁륭부 지주막 낭종 - 증 례 보 고 -

김성림,박해관,박성찬,나형균,강준기,최창락,Kim, Seong-Rim,Park, Hae Kwan,Park, Sung Chan,Rha, Hyung Kyun,Kang, Joon Ki,Choi, Chang Rak 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.2

Arachnoid cysts are defined as duplicated arachnoids and their splitting with congenital, intra-arachnoid, and leptomeningeal malformations. They are most commonly located in the middle cranial fossa followed by suprasellar and quadrigeminal cisterns, posterior fossa, and very rare in cerebral convexities. They are often ruptured by trauma or spontaneously and cause subdural hygroma or subdural hematoma. Authors report a case of a 32-year-old woman with a convexity arachnoid cyst mimicking subdural hygroma associated with a separate middle fossa arachnoid cyst. Preoperatively, the convexity arachnoid cyst was misinterpreted as subdural hygroma resulted from a ruptured middle fossa cyst. The patient underwent craniotomy and cyst fenestration into the basal cistern. Two separate arachnoid cysts were found in the cerebral convexity and middle cranial fossa during the operation. Finally, cysts were resolved and she was discharged without any complication.

구심로 차단 동통에서의 미세 후근 진입부 절제술

김성림,이경진,조정기,나형균,박해관,강준기,최창락,Kim, Seong-Rim,Lee, Kyung Jin,Cho, Jeong Gi,Rha, Hyung Kyun,Park, Hae Kwan,Kang, Joon Ki,Choi, Chang Rak 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.1

Objective : DREZotomy is effective for the treatment of deafferentation pain as a consequence of root avulsion, postparaplegic pain, posttraumatic syrinx, postherpetic neuralgia, spinal cord injury, and peripheral nerve injury. We performed microsurgical DREZotomy to the patients with deafferentation pain and relieved pain without any serious complication. The purpose of this study is to evaluate the usefulness of the microsurgical DREZotomy for deafferentation pain. Methods : We evaluated 4 patients with deafferntation pain who were intractable to medical therapy. Two of them were brachial plexus injury with root avulsion owing to trauma, one was axillary metastasis of the squamous cell carcinoma of the left forearm, and the last was anesthesia dolorosa after surgical treatment(MVD and rhizotomy) of trigeminal neuralgia. Preoperative evaluation was based on the neurologic examination, radiologic imaging, and electrophysiological study. In the case of anesthesia dolorosa, we produced two parallel lesions in cephalocaudal direction, 2mm in distance, from the C2 dorsal rootlet to the 5mm superior to the obex including nucleus caudalis, after suboccipital craniectomy and C1-2 laminectomy, with use of microelectrode. In the others, we confirmed lesion site with identification of the nerve root after hemilaminectomy. We performed arachnoid dissection along the posterolateral sulcus and made lesion with microsurgical knife and microelectrocoagulation, 2mm in depth, 2mm in distance, to the direction of 30-45 degrees in the medial portion of the Lissauer's tract and the most dorsal layers of the posterior horn at the one root level above and below the lesion. Results : Compared with preoperative state, microsurgical DREZotomy significantly diminished dosage of the drugs and relieved pain meaningfully. One patient showed tansient ipsilateral ataxia, but recovered soon. There was not any serious complication. Conclusion : It may be concluded that microsurgical DREZotomy is very useful and safe therapeutic modality for deafferentation pain, especially segmentally distributed intermittent or evoke pain. Complete preoperative evaluation and proper selection of the patients and lesion making device are needed to improve the result.

신경외과 영역에서의 미세혈관 문합술

나형균,이경진,조경근,박성찬,박해관,조정기,지철,최창락,Rha, Hyoung-Kyun,Lee, Kyung-Jin,Cho, Kyung-Keun,Park, Sung-Chan,Park, Hae-Kwan,Cho, Jung-Ki,Ji, Chul,Choi, Chang-Rak 대한미세수술학회 1999 Archives of reconstructive microsurgery Vol.8 No.2

Objective : Extracranial-intracranial(EC-IC) microvascular anastomosis was performed in 18 patients with hemodynamic cerebral ischemia and traumatic cerebral aneurysm, the aim of this retrospective study was to assess its value in neurosurgical field. Method : Of 18 cases, 17 case were hemodynamic cerebral ischemia and one was traumatic cerebral aneurysm. There were 14 superficial temporal artery(STA)-to-middle cerebral artery(MCA) anastomosis, 3 saphenous vein graft bypass(2 external carotid artery(ECA)-to-MCA, 1main trunk of the STA-to-MCA) and 1 radial artery bypass(ECA-to-MCA). Results : Bypass patency was confirmed by postoperative angiography in all cases except for two cases, postoperative cerebral blood flow of ischemic brain showed significant increased in all cases with good patency through bypass. Conclusion : Revascularization by EC-IC microvascular anastomosis to the ischemic brain eliminated ischemia and was associated with excellent good outcome and good patency rates.

The Relationship between Intracellular Protein Kinase C Concentration and Invasiveness in U-87 Malignant Glioma Cells

지철,조경근,이경진,박성찬,조정기,강준기,최창락,Ji, Cheol,Cho, Kyung-Keun,Lee, Kyung Jin,Park, Sung Chan,Cho, Jung Ki,Kang, Joon Ki,Choi, Chang Rak The Korean Neurosurgical Society 2001 Journal of Korean neurosurgical society Vol.30 No.3

교모세포종은 비교적 흔한 원발성 뇌종양이며 생물학적 특성상 빠른 성장률을 보이는 것 외에 침습성이 강하여 종양과 인접한 부분을 파괴 시킬 뿐 아니라 직접접촉하지 않는 부분의 파괴도 일어나게 되어 그 결과 치료 예후가 매우 불량한 것으로 되어 있다. 이러한 불량한 예후를 개선 시키기 위해서는 이들 종양의 침습에 대한 기전의 정확한 이해가 필요하며 이를 이용한 새로운 치료방법이 요구된다할 것이다. Protein kinase C(PKC)는 세포내 신호전달체제 과정에서 매우 중요한 역할을 하는 효소로 세포막 수용체 신호를 핵으로 전달하는 역할을 하며 세포내 여러 생물학적 작용이 알려져 있다. 본 실험은 종양침습과 연관하여 세포내 PKC가 어떠한 작용을 하는지에 대해서 악성교종 세포를 대상으로 하여 알아보고자 하였다. 따라서 PKC가 종양침습에 중요한 역할을 할 것이라는 가설을 세웠고 이 가설을 증명하기 위해 세포내 PKC농도를 길항제 및 촉진제를 이용하며 높고 낮게 조절함으로써 그에 따른 침습성의 변화를 살펴보았다. 방법으로는 교모세포종 세포주인 U-87 세포를 약제로 처리한 후 인위적으로 조절된 세포내의 PKC에 대해 효소의 활성도를 측정하였고 침습성은 matrigel artificial basement membrane assay 및 tumor spheroid fetal rat brain aggregate(FRBA) confrontation assay를 이용하여 측정하였다. 결과로 PKC의 길항제인 tamoxifen과 hypericin으로 처치한 세포는 PKC의 활성과 침습도가 모두 감소하였으며 이는 약제농도에 비례하여 나타났다. 반면 PKC 자극제인 TPA로 처치된 세포는 증가된 PKC 활성도나 침습도을 보이지 않았다. 이러한 결과를 종합해 보았을 때 PKC는 종양세포의 침습성에 중요한 역할을 함을 알 수 있었으며 PKC의 길항제는 종양 치료에 유용한 화학 요법 제가 될 수 있을 것으로 사료된다. Objective : Glioblastomas, the most common type of primary brain tumors, are highly invasive and cause massive tissue destruction at both the tumor invading edges and in areas that are not in direct contact with glioma cells. As a result, patients with high-grade gliomas are faced with a poor prognosis. Such grim statistics emphasize the need to better understand the mechanisms that underlie glioma invasion, as these may lead to the identification of novel targets in the therapy of high grade gliomas. Protein kinase C(PKC) is a family of serine/threonine kinases and an important signal transduction enzyme that conveys signals generated by ligand-receptor interaction at the cell surface to the nucleus. PKC appears to be critical in regulating many aspects of glioma biology. The purpose of this study was to assess accurately the role of PKC in the invasion regulation of human gliomas based on hypothesis that protein kinase C(PKC) is functional in the process of glial tumor cell invasion. Method : To test this hypothesis, U-87 malignant glioma cell line intracellular PKC levels were up and down regulated and their invasiveness was tested. Intracellular PKC level was characterized using PKC activity assays. Invasion assays including barrier migration and spheroid confrontation were used to study the relationship between PKC concentration and invasiveness. Result : The cell line which were treated by PKC inhibitor tamoxifen and hypericin exhibited decreased PKC activity and decreased invasive abilities dose dependently both in matrigel invasion assay and tumor spheroid fetal rat brain aggregates(FRBA) confrontation assay. However, the cell line that was treated by PKC activator 12-O-tetradecanylphorbol-13acetate(TPA) did not exhibit increases in either PKC activity or invasive ability. Conclusion : These studies suggest that PKC may be a useful molecular target for the chemotherapy of glioblastoma and other malignancies and that a therapeutic approach based on the ability of PKC inhibitors may be helpful in preventing invasion.

실험관 및 생체내에서 U-87 교모세포종 세포주의 광역학 치료 효과에 대한 연구

조우진,조경근,지철,박성찬,박해관,강준기,최창락,Cho, Woo Jin,Cho, Kyung-Keun,Ji, Cheol,Park, Sung Chan,Park, Hea Kwan,Kang, Joon Ki,Choi, Chang Rak 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.5

Objective : The objective of this study was to determine the photodynamic therapeutic response of U-87 human glioma cell in vitro as well as in the nude rat xenograft model using photofrin as photosensitizer. Material and Method : U-87 cells were cultured on 96-well culture plates, photofrin(Quadralogic Technologies Inc., Vancouver, Canada) was added into the cell culture medium at concentration of $1{\mu}g/ml$, $2.5{\mu}g/ml$, $5{\mu}g/ml$, $10{\mu}g/ml$ and $20{\mu}g/ml$. 24 hour after drug treatment, cells were treated with optical(632nm) irradiation of $100mJ/cm^2$, $200mJ/cm^2$ and $400mJ/cm^2$. Photofrin(12.5mg/kg, i.p.) was administered to 28 nude rats containing intracerebral U-87 human glioma as well as 26 normal nude rats. 48 hours after administration, animals were treated with optical irradiation(632nm) of $35J/cm^2$, $140J/cm^2$ and $280J/cm^2$ to exposed tumor and normal brain. The photofrin concentration was measured in tumor and normal brain in a separate population of animals. Results : By MTT assay, there was 100% cytotoxicity at any dose of photofrin with optical irradiation of $200mJ/cm^2$ and $400mJ/cm^2$. But at the optical irradiation of $100mJ/cm^2$ cells were killed in dose dependent manner 28.5%, 49.1%, 54.4%, 78.2%, and 84.6% at concentration of $1{\mu}g/ml$, $2.5{\mu}g/ml$, $5{\mu}g/ml$, $10{\mu}g/ml$ and $20{\mu}g/ml$, respectively. Dose dependent PDT lesions in both tumor and normal brain were observed. In the tumor lesion, only superficial tissue damage was found with optical irradiation of $35J/cm^2$. However, in the optical irradiation group of $140J/cm^2$ and $280J/cm^2$ the volume of lesions was measured of $7.2mm^3$ and $14.0mm^3$ for treatment at $140J/cm^2$ and $280J/cm^2$, respectively. The U-87 bearing rats showed a photofrin concentration in tumor tissue of $6.53{\pm}2.16{\mu}g/g$, 23 times higher than that found in the contralateral hemisphere of $0.28{\pm}0.15{\mu}g/g$. Conclusion : Our data indicate that the U-87 human glioma in vitro and in the xenografted rats is responsive to PDT. At these doses, a reproducible injury can be delivered to human glioma in this model. Strategies to spare the normal brain collateral damage are being studied.