두개외 경동맥 및 두개내 협착과 베타 아밀로이드 침착 및 신경 퇴화와의 연관성: 임상 단계별 접근법

학위논문 (박사) -- 서울대학교 대학원 : 의과대학 의학과, 2021. 2. 손철호.Background: Although accumulating evidence suggests that cerebrovascular disease may contribute to the development of Alzheimer’s disease (AD), it remains unclear whether atherosclerosis of the carotid and intracranial arteries is related to the AD pathology in vivo. Thus, we investigated the associations of carotid and intracranial artery stenosis with in vivo cerebral beta-amyloid (Aβ) deposition and neurodegeneration in middle- and old-aged individuals. Given the differential progression of Aβ deposition and neurodegeneration across clinical stages of AD, we focused separately on cognitively normal (CN) and cognitively impaired (CI) groups. Methods: A total of 281 CN and 199 CI (mild cognitive impairment and AD dementia) subjects underwent comprehensive clinical assessment, [11C] Pittsburgh Compound B-positron emission tomography, and magnetic resonance (MR) imaging including MR angiography. We evaluated extracranial carotid and intracranial arteries for the overall presence, severity (i.e. number and degree of narrowing) and location of stenosis. Results: There were no associations between carotid and intracranial artery stenosis and cerebral Aβ burden in either CN or CI group. In terms of neurodegeneration, exploratory univariable analyses showed some associations between the presence and severity of stenosis and regional neurodegeneration biomarkers (i.e. reduced hippocampal volume [HV] and cortical thickness in the AD-signature regions) in both CN and CI groups. In confirmatory multivariable analyses controlling for demographic covariates and diagnosis, the association between number of stenotic intracranial arteries ≥ 2 and reduced HV in the CI group remained significant. Conclusions: Neither carotid nor intracranial artery stenosis appears to be associated with brain Aβ burden, while intracranial artery stenosis is related to amyloid-independent neurodegeneration, particularly hippocampal atrophy. These observations support the importance of proper management of intracranial artery stenosis for delaying the progression of AD neurodegeneration and related cognitive decline.서론: 뇌 혈관 질환이 알츠하이머 병 (AD)의 발병에 기여할 수 있음을 시사하는 증거들이 축적되고 있지만, 경동맥 및 두개내 동맥의 죽상 동맥 경화증이 생체 내 AD 병리와 관련이 있는지 여부는 명확하지 않다. 경동맥과 두개내 혈관의 협착이 알츠하이머병 병리와 관련이 있는지를 알아보기 위해, 대뇌 베타 아밀로이드 침착과 신경퇴행성 변화와 경동맥 및 두개내 혈관 협착과의 관계를 중년 및 노년 인구에서 조사하였다. 인지 기능 상태에 따라 AD 병리에 차이가 있음에 고려하여 인지기능 정상군과 인지기능 저하군에서 각각 연구를 시행하였다. 방법: 281명의 인지기능 정상군과 199명의 인지기능 저하군이 임상 평가를 받고, [11C] Pittsburgh compound B-양전자단층촬영, 자기공명혈관조영술을 포함한 자기공명영상을 시행하였다. 경동맥과 두개내 혈관의 협착 유무, 협착의 심각성(협착 수와 협착된 정도), 그리고 협착의 위치를 평가하였다. 결과: 두 군에서 모두 경동맥과 두개내 혈관의 협착과 대뇌 베타 아밀로이드 침착간의 관련성은 없었다. 신경퇴행성 변화에 대한 탐색적 단변수 분석에서 두 군 모두 협착의 유무 및 심각성과 지역적 신경퇴행성 바이오마커 (해마 부피 감소, 알츠하이머병 특정 부위의 피질 두께 감소)간에 관련성이 있었다. 인구학적 변수와 진단명을 통제한 확증적 다변수 분석에서는 인지기능 저하군에서, 협착이 있는 두개내 혈관의 수가 2군데 이상인 것과 해마 부피 감소가 관련성이 있었다. 결론: 경동맥과 두개내 혈관의 협착 모두 대뇌 베타 아밀로이드 침착과 관련이 없는 반면, 두개내 혈관의 협착은 인지기능 저하군에서 해마위축으로 나타나는 신경퇴행성 변화와 관련이 있었으며, 이는 아밀로이드 침착과는 독립적이었다. 본 연구는 AD의 치료에 뇌혈관질환의 조절이 신경퇴행성변화를 지연하는데 중요한 역할을 할 것임을 시사한다.Abstract i Contents.. iii List of tables.. iv List of figures....vi Introduction . 1 Materials and Methods.. 3 Results 12 Discussion.. 33 References.. 38 Abstract in Korean 43Docto

Gel phantom study with HIFU: Influence of metallic stent containing either air or fluid

학위논문 (석사)-- 서울대학교 대학원 : 의학과(영상의학전공), 2014. 2. 이재영.Purpose: We aimed to investigate whether a cylindrical structure containing either air or fluid and with or without a metallic stent affects the volume and density of cavitation produced by high-intensity focused ultrasound (HIFU) via a gel phantom study. Materials and Methods: Sixteen phantoms with a cylindrical hole were divided into 4 groups of 4 phantoms with air in the holes (Group 1), 4 phantoms with fluid in the holes (Group 2), 4 phantoms with air-containing metallic stents (Group 3), and 4 phantoms with fluid-containing metallic stents (Group 4). The VIFU-2000 small animal HIFU unit (ALPINION Medical Systems, Seoul, Korea) was used with acoustic power (100W), exposure time (36 sec.), duty cycle (50%) and pulse repetition frequency (40 Hz). The focus of the HIFU beam was placed at the posterior wall of the hole in the phantom. The size of cavitation on x-, y-, and z-axis was measured, and the volume of cavitation and coagulation was calculated using the formula for the volume of an elliptical cone. The density of cavitation was measured in the tissue phantom anterior to the hole with 1cm x1cm square region of interest. For statistical analysis, Kruskal-Wallis test and Mann-Whitney U test were used. Results: The volume of anterior cavitations of Groups 1 and 3 were significantly larger than those of Groups 2 and 4 (P .05). The size on all axes and volumes of anterior cavitations were significantly larger than those of posterior cavitations only in Groups 1 and 3 (all P < .05). Regarding the density, anterior cavitations of Groups 1 and 3 were significantly denser than that of Groups 2 and 4. (P < .05). Conclusion: Phantoms with air-containing holes developed larger and denser cavitations anterior to the focus without unnecessary coagulation posterior to the focus, regardless of the presence of stents. The result of this study might be applied to maximize cavitation to enhance drug delivery into tumors before air-containing duct or stent.Abstract i Contents iii List of tables and figures iv List of abbreviations. v Introduction 1 Material and Methods 3 Results 8 Discussion 12 References 15 Abstract in Korean 19Maste

重金屬이 Cyanobacterium synechocystis sp. PCC 6803의 生長과 蛋白質 合成에 미치는 影響

학위논문(석사)--서울大學校 大學院 :科學敎育科 生物專攻,1997.Maste

Phylogenetic analysis of Korean cellular slime molds based on ribosomal DNA sequences and development of inquiry experimental materials using cellular slime molds

학위논문(박사)--서울대학교 대학원 :과학교육과 생물 전공,2001.Docto

Equilibrium Between Pollutant Load and Self-purification in Forest Ecosystem

The purpose of this study is to investigate equilibrium between pollutant load and self-purification in forest ecosystem. The results are as follows. In the coniferous forest, the load of organic matter was 152-828 g/m²/year, and the load of holocellulose, 52~284 g/m²/year; in the oak forest, 249~1,028 g/m²/year and 44-211 g/m²/year, respectively. This result showed that the load of the oak forest was higer than that of the coniferous forest. The self-purification coefficients of organic matter and holocellulose were 0.10~0.26 and 0.17~0.42 in the coniferous forest, and 0.17~0.28 and 0.56~0.71 in the oak forest. The self-purification coefficient of holocellulose was higher than that of organic matter in both forests, and the value of organic matter and holocellulose in the oak forest was about two times in coniferous forest. Filter papers buried in the humus layer of Rigida forest were decomposed about two times faster than Pinus rigida leaves. The self-purification coefficients decreased as the altitude and latitude increase, and they were high in the south and the south-east and lowest in the north