Leigh Syndrome: Subgroup Aanalysis according to Mitochondrial DNA Mutation

Purpose: Leigh syndrome (LS) is a rare, progressive neurodegenerative disorder with characteristic abnormalities in the central nervous system. Such patients present with heterogeneous clinical symptoms and genetic abnormalities; thus, prognosis is difficult to anticipate. The present study investigates whether distinct patient characteristics are associated with mitochondrial DNA (mtDNA) mutation in LS patients. Methods: : We retrospectively analyzed data from patients diagnosed with LS at our hospital who were assessed using genomic sequencing of mtDNA. A subgroup analysis was performed to divide patients according to the mtDNA sequencing results. Results: Among the 85 patients enrolled, 18 had mtDNA mutations. Most patients had lactic acidosis and a lactate/pyruvate ratio above 20, indicating respiratory chain abnormalities. In the subgroup analysis, the mutation group had a significantly higher female-to-male ratio, alanine level, ocular involvement, and midbrain and medulla abnormalities on magnetic resonance imaging (MRI). Conclusion: The subgroup analysis indicates that mtDNA sequencing is recommended for female patients, or those who exhibit ocular involvement, high alanine levels, or MRI findings with lesions in the midbrain and medulla.ope

학교 내 대안교실 사례를 중심으로

학위논문(석사) -- 서울대학교대학원 : 사범대학 교육학과(교육학전공), 2021.8. 유성상.This study aims to identify the process in which students who are maladjusted at school, maintain their school lives through ‘an alternative classroom in school,’ and to see how teachers perceive the school-adjustment process and make it meaningful. The study started with raising a question of whether it is fair to distinguish between students who are non-maladjusted and maladjusted according to the standards prescribed by society and schools and to ask for change from individuals who are maladjusted. To solve this problem, this study conducted interview-driven qualitative research on teachers in charge of alternative classrooms by selecting the cases that are operated separately from ordinary classes for students who are maladjusted at schools. The results of this study are summarized as follows. The teachers perceived the purpose of alternative classrooms as ‘for graduation’, ‘for maintenance of school life’ and ‘providing alternative educational opportunities.’ Also, they viewed the characteristics of students who fail to adjust themselves to alternative classrooms as causing problems that are apparently noticeable, refusing classes, and being silent because they do not fit the school system. Students who exhibit these maladjustment characteristics are found mainly through the teacher’s continuous observation. Furthermore, a process of persuading those students to participate in an alternative classroom operates, when it is judged that they need help. Alternative classroom activities are encouraged by teachers to give options to participating students who are maladjusted and find activities that they want to do independently rather than pre-determined. The alternative classroom consists of a variety of subject-oriented activities in a free and flexible manner. Meanwhile, school members’ perceptions of alternative classrooms and students where are maladjusted were mostly negative. The purpose and operation of these alternative classes served as a ‘school life maintenance system’ for students who were maladjusted at school. The teachers perceived the main changes in students who were maladjusted through alternative classes as adjustment’ and ‘maintenance’ of school life. In other words, this can be seen as ‘an improved attitude in class’ before participating in alternative classes or ‘a change in maintaining school life without leaving school.’ However, it was followed by opinions that such changes in students who were maladjusted are only seen for a while, and thus, the fundamental problem of maladaptation could not be seen as gone. That is, the existing schools and classrooms where students lived are still the same, and the environment that was inappropriate has not changed, so the phenomenon of maladjustment can reappear at any time. The reason why alternative classes can only serve as a temporary school life maintenance system for students who are maladjusted at school was because it was the limitations of the standardized curriculum and assessment system as well as the expected student image in class. Furthermore, the expected student image in class which sustains such a reproduction structure, allows maladjusted students to be marginalized in school. Alternative classes were intended to provide ‘Alternative Education in Public Education’ opportunities for students who are maladjusted at school, but behind this, they were operated mainly for the prevention of academic interruptions through national intervention. In addition, through the ambiguous distinction between non-alternative classes and alternative classes, the method of ‘inclusive control’ was chosen, rather than complete isolation of students who are maladjusted. Using the marginalized (separated) space and time of alternative classrooms, the scope of school adjustment standards and school education is expanded, and thus it looks like that the previously maladjusted individuals have changed and coexist in schools together. As such, maladjusted students were clearly recognized in school in the past, and today it seems that they coexist together, but as this study confirmed, they remain maladjusted and are becoming ambiguously marginalized.본 연구는 학교부적응 학생이 ‘학교 내 대안교실’을 통해 학교생활을 지속하는 과정을 파악하고, 교사는 이들의 학교적응과정을 어떻게 인식하고 의미화하는지 살펴보는 것을 목적으로 한다. 이 연구는 사회와 학교에서 규정하는 기준에 따라 일반학생과 부적응학생을 구분 짓고, 부적응한 개인에게 변화를 요구하는 것이 과연 정당한 것인가에 대한 문제 제기로부터 시작하였다. 이를 위해 본 연구에서는 학교부적응 학생을 대상으로 일반학급과 구분하여 운영하는 대안교실 사례를 선택하여, 대안교실 담당교사들을 대상으로 면담 중심의 질적 연구를 진행하였다. 본 연구의 결과와 논의를 요약하면 다음과 같다. 대안교실 담당교사들은 대안교실의 목적을 ‘졸업’과 ‘학교생활 유지’, 그리고 ‘대안적인 교육의 기회 제공’으로 인식하였다. 또한, 대안교실에 참여하는 학교부적응 학생의 특징으로 눈에 띄는 문제를 일으키거나, 수업을 거부하고, 학교 시스템에 맞지 않아 침묵하는 것으로 보았다. 이러한 부적응 특징을 보이는 학생은 주로 교사의 지속적인 관찰을 통해 발견되었다. 더 나아가, 도움이 필요한 수준이라고 판단될 때 대안교실에 참여하도록 해당 학생을 설득하는 과정을 거친다. 대안교실 활동은 교사가 미리 정하기보다 참여하는 부적응학생에게 선택권을 주고, 주체적으로 하고 싶은 활동을 찾도록 권장한다. 그리고 자유롭고 유연한 방식으로 다양한 주제 중심의 활동이 구성된다. 한편, 대안교실과 부적응학생에 대한 학교구성원들의 인식은 대부분 부정적인 것으로 나타났다. 이러한 대안교실의 목적과 운영과정은 학교부적응 학생의 ‘학교생활 유지기제’ 역할을 하였다. 교사들은 대안교실을 통한 부적응학생의 주된 변화를 학교생활의 ‘적응’과 ‘유지’로 인식하고 있었다. 다시 말해, 대안교실 참여 전보다 ‘수업 태도가 좋아졌거나’, ‘학교를 그만두지 않고 학교생활을 유지하게 된 것’을 부적응학생의 변화라고 인식하였다. 그러나 이러한 변화는 잠시 그렇게 보이는 것일 뿐 근본적인 부적응 문제가 사라진 것으로 볼 수 없다는 의견이 뒤따랐다. 즉, 학생이 생활하던 기존의 학교와 교실은 여전히 그대로이고 부적응하던 환경은 변화된 것이 없으므로 부적응 현상은 언제든 다시 나타날 수 있다는 것이다. 이처럼 대안교실이 부적응학생의 일시적인 학교생활 유지 기제 역할밖에 할 수 없는 이유는 교실 안에서 기대하는 학생의 모습과 표준화된 교육과정 및 평가 시스템의 한계였다. 그리고 이러한 구조를 유지하게 하는 학교 안 개인은 부적응학생이 학교 안에서 주변화되도록 하였다. 대안교실은 학교부적응 학생을 대상으로 ‘공교육 내 대안교육’ 기회를 제공하고자 하였으나, 그 이면에는 국가적 개입을 통한 학업중단 예방 목적을 중심으로 운영되었다. 또한, 일반학급과 대안교실의 애매한 구분짓기를 통해 부적응학생의 완전한 격리가 아닌 ‘끌어안는 통제’ 방식을 선택하였다. 대안교실이라는 주변화된(분리된) 공간과 시간을 이용하여 학교부적응의 기준과 학교교육의 범위를 넓혀보니, 예전에는 부적응했던 개인이 변화하여 학교 안에 함께 공존하는 것처럼 보인다. 이처럼 과거에는 학교 안 부적응학생이 명확하게 인식되었다면, 지금은 함께 공존하는 듯하지만, 여전히 부적응한 상태로 애매한 주변화가 되어 있는 것을 확인할 수 있다.제 1 장 연구의 필요성 및 목적 1 제 2 장 선행연구 및 이론적 배경 5 제 1 절 ‘학교부적응’ 개념과 특징 5 1. 학교부적응의 개념 5 2. 학교부적응 특징 7 3. 학교부적응 원인 8 제 2 절 학교부적응에 대한 정책적 접근 11 1. 비행행위로서의 학교부적응 12 2. 학업중단 원인으로서의 학교부적응 13 3. 학업중단 예방정책 16 제 3 절 학교부적응 선행연구 현황 및 한계 20 1. 학교부적응 선행연구 유형 20 2. 학교부적응 문제에 대한 관점 24 제 3 장 연구방법 26 제 1 절 연구 참여자의 선정 27 1. 연구 사례 27 2. 연구 참여자 소개 30 제 2 절 자료 수집 및 분석 34 1. 면담 34 2. 면담자료 분석 36 제 4 장 학교부적응 학생을 위한 ‘또 다른 교육’: 학교 내 대안교실 39 제 1 절 학교 내 대안교실의 목적 39 1. 졸업: “무사히 졸업할 수 있도록 도와주는 거죠” 39 2. 학교생활 유지: “잠시 숨 쉴 수 있는 시간을 주는 거죠” 42 3. 학교 경험의 다양화 시도: “학교에서 또 다른 결들을 제시해주는 거죠” 44 제 2 절 학교부적응으로 보이는 학생 선별 48 1. 교사가 인식하는 학교부적응 학생의 특징 48 2. 대안교실 참여학생 선정과정 56 제 3 절 학교부적응 학생을 위한 대안교실 활동 62 1. 교육의 주체성 회복: ‘뭐 하고 싶니?’를 물어보는 것 62 2. 대안교실 활동구성의 유연성 64 3. 대안교실 활동 주제 68 제 4 절 대안교실에 대한 인식 75 1. ‘문제 있는 애들’이 가는 곳: “대안교실에 가는 게 당연해” 75 2. 학습결손에 대한 우려: “그래도 수업시간에 엎드려 있을 바에” 77 3. 예산과 에너지 낭비: “굳이 이 돈을 쟤네한테? 왜 쟤네들만?” 80 4. 역차별에 대한 우려: “선생님, 저도 부적응 할래요” 82 5. 부적응학생에 대한 교사들의 인식: “이해할 수 없는 존재들” 84 제 5 장 학교부적응과 학교적응과정의 의미 87 제 1 절 학교생활 유지기제로서의 대안교실 87 1. 학교생활 적응: “태도가 조금씩 바뀌어요” 87 2. 잠시 유예된 부적응: “그 환경으로 돌아가면 언젠가 부적응은 또 발생해요” 91 제 2 절 학교부적응과 변하지 않은 학교 94 1. 학교가 요구하는 기준과 주변화된 부적응 95 2. 기존 틀을 유지하려는 교사 102 제 3 절 종합논의 105 1. 학교의 기능을 유지하기 위한 대안교실의 모순 105 2. 부적응학생의 일시적인 학교생활 유지기제 110 제 6 장 요약 및 결론 113 제 1 절 요약 113 제 2 절 결론 115 참고문헌 117 Abstract 129석

유전경직성하반신마비 단백질인 Spartin에 의한 시냅스 성장과 신경세포 생존의 조절

학위논문 (박사)-- 서울대학교 대학원 : 치의과학과 신경생물학 전공, 2013. 8. 이승복.Troyer 증후군은 complicated HSP의 한 종류로써, 지금까지 Troyer 증후군과 관련된 원인 유전자는 spartin (SPG20)이 밝혀져 있다. 본 연구는 초파리를 동물 모델로 이용하여, Spartin의 시냅스 전 말단에서의 기능과 Troyer 증후군의 병리기전을 규명하였다. Spartin은 시냅스 막과 early endosome에서 특이적으로 발현되며, endocytic adaptor 단백질인 Eps15와 상호작용을 통해 시냅스 성장과 기능을 조절함을 밝혔다. Spartin은 시냅스 전 말단에 존재하는 BMP 수용체인 Wishful Thinking (Wit)의 endocytic degradation을 유도하여 BMP 신호전달을 억제함으로써 시냅스 성장을 저해하며, 이러한 Spartin/BMP 신호전달은 Drosophila fragile X mental retardation protein (dFMRP)-Futsch 신호전달과정을 통하여 미세소관의 안정성을 유도함으로써 시냅스 성장을 억제함을 규명하였다. 시냅스의 기능과 더불어 spartin의 결손과 BMP 신호전달의 과도한 활성은 HSP 환자들에서 보고된 age-dependent한 운동장애가 관찰되었다. 또한 돌연변이 성체 뇌에서 neurodegeneration에 의한 vacuole 형성이 확인되었으며 이러한 vacuole 형성은 신경세포의 사멸에 의해 유도됨을 규명하였다. 특히 spartin 돌연변이에서 관찰된 시냅스의 과 성장과 성체 뇌의 neurodegeneration에 의한 이상은 미세소관의 안정성을 저해하는 약물인 Vinblastine (VB)에 의해 모두 회복됨을 관찰하였다. Spartin이 BMP-dFMRP-Futsch 신호전달을 억제하여 미세소관 안정성을 조절하며, 이를 통해 시냅스 성장과 신경 세포 사멸을 억제함를 밝힌 본 연구는 미세소관의 비정상적인 안정성 조절이 Troyer 증후군이 유발되는 핵심기전임을 제시한다.Troyer syndrome is a hereditary spastic paraplegia caused by human spartin (SPG20) gene mutations. I have generated a Drosophila disease model showing that Spartin functions presynaptically with endocytic adaptor Eps15 to regulate synaptic growth and function. Spartin inhibits bone morphogenetic protein (BMP) signaling by promoting endocytic degradation of BMP receptor Wishful Thinking (Wit). Drosophila Fragile X Mental Retardation Protein (dFMRP) and Futsch/MAP1B are downstream effectors of Spartin and BMP signaling in regulating microtubule stability and synaptic growth. Loss of Spartin or elevation of BMP signaling induces age-dependent progressive defects resembling hereditary spastic paraplegias, including motor dysfunction and brain neurodegeneration. Null spartin phenotypes are prevented by administration of the microtubule-destabilizing drug vinblastine. Together, these results demonstrate that Spartin regulates both synaptic development and neuronal survival by controlling microtubule stability via the BMP-FMRP-Futsch pathway, suggesting that impaired regulation of microtubule stability is a core pathogenic component in Troyer syndrome.CONTENTS ABSTRACT CONTENTS LIST OF FIGURES ABREVIATIONS I. Introduction 1. Retrograde Bone Morphogenetic Protein (BMP) Signaling in Synapse Development 2. Troyer Syndrome, Is an Autosomal Recessive Form of Hereditary Spastic Paraplegia that Is Caused by Loss-of-Function Mutations in the spartin Gene (SPG20) 3. The Drosophila Neuromuscular Junction (NMJ) and Adult Brain 4. Rationale and Outline of the Thesis Experiments II. Materials and Methods 1. Drosophila Stocks and Transgenes 2. Molecular Biology 3. Cell Culture and Double-Stranded RNA Interference 4. Generation of Anti-Spartin Antibody and Western Blot Analysis 5. Immunohistochemistry and Imaging of Larval NMJs 6. Electrophysiology and FM1-43 Uptake Assays 7. Histology, Immunostaining, and TUNEL Staining of Adult Brains 8. Adult Behavioral Analysis 9. Statistical Analysis III. Results 1. Generation of spartin Null Mutant 2. Spartin Is Localized Presynaptically at the NMJ 3. Spartin Is Required Presynaptically for Normal Synaptic Growth 4. Spartin Is Required Presynaptically for NMJ Neurotransmission 5. Spartin Interacts with Eps15 to Regulate Synaptic Growth and Synaptic Endocytosis 6. Spartin Inhibits BMP Signaling by Endocytic Downregulation of the Type II BMP Receptor Wit 7. Spartin Regulates Synaptic Growth by Modulating Microtubule Stability through Futsch 8. Spartin and BMP Signaling Regulate the Expression of dFMR1, a Negative Regulator of Futsch 9. Loss of spartin Function in Neurons Causes Movement Defects and Progressive Neurodegeneration 10. Spartin/BMP-Mediated Regulation of Microtubule Stability Is Critical for Neuronal Survival IV. Discussion V. References ABSTRACT IN KOREANDocto

Interactions between Shh, Sostdc1 and Wnt signaling and a new feedback loop for spatial patterning of the teeth

Each vertebrate species displays specific tooth patterns in each quadrant of the jaw: the mouse has one incisor and three molars, which develop at precise locations and at different times. The reason why multiple teeth form in the jaw of vertebrates and the way in which they develop separately from each other have been extensively studied, but the genetic mechanism governing the spatial patterning of teeth still remains to be elucidated. Sonic hedgehog (Shh) is one of the key signaling molecules involved in the spatial patterning of teeth and other ectodermal organs such as hair, vibrissae and feathers. Sostdc1, a secreted inhibitor of the Wnt and Bmp pathways, also regulates the spatial patterning of teeth and hair. Here, by utilizing maternal transfer of 5E1 (an anti-Shh antibody) to mouse embryos through the placenta, we show that Sostdc1 is downstream of Shh signaling and suggest a Wnt-Shh-Sostdc1 negative feedback loop as a pivotal mechanism controlling the spatial patterning of teeth. Furthermore, we propose a new reaction-diffusion model in which Wnt, Shh and Sostdc1 act as the activator, mediator and inhibitor, respectively, and confirm that such interactions can generate the tooth pattern of a wild-type mouse and can explain the various tooth patterns produced experimentally.ope

Comparison of Postoperative Gastrointestinal Motility of Sugammadex and Neostigmine in Patients Undergoing Robotic Thyroidectomy: A Retrospective Study

Postoperative bowel dysfunction poses difficulty to patients during their recovery from surgery, and reversal agents may affect bowel function. This study aimed to investigate and compare the effects of sugammadex and a neostigmine/glycopyrrolate combination on postoperative bowel movement in patients undergoing robotic thyroidectomy. The electronic medical records of 122 patients, who underwent robotic thyroidectomy between March 2018 and December 2020, were retrospectively reviewed. Demographic, clinical, and laboratory findings and the first gas-passing time after surgery were assessed. The number of patients with a first gas emission time over 24 h was significantly higher in the neostigmine group than in the sugammadex group (p = 0.008). Multivariate logistic regression analysis indicated that sugammadex was a prognostic factor for the first gas-passing time within 24 h (odds ratio = 4.60, 95% confidence interval 1.47-14.36, p = 0.005). Although postoperative bowel motility, based on the first gas emission time, was comparable, the number of patients with a first gas emission time within 24 h was significantly higher in the sugammadex group than in the neostigmine group. This shows that the use of sugammadex did not affect the delayed recovery of postoperative bowel motility after robotic thyroidectomy.ope

Effects of hyaluronan on carrageenan-induced synovitis in rat TMJ

Nitric oxide is one of many proinflammatory mediators that are involved in temporomandibular joint (TMJ) inflammatory disorder and is synthesized by inducible nitric oxide synthase (iNOS). iNOS is transcriptionally regulated by nuclear factor-kappaB (NF-kappaB) in cases of inflammation, proliferation, and apoptosis. It has also been reported that nitric oxide is positively regulated by carrageenan and negatively regulated by hyaluronan in the knee joint. The aim of this study was to histologically evaluate how inflammation and cell proliferation of the synovial membrane are affected by the exogenous administration of carrageenan and hyaluronan in the rat TMJ by investigating iNOS, NF-kappaB, and anti proliferating cell nuclear antigen (PCNA) immunoreactivity. As results, immunoreactive cells to iNOS, NF-kappaB, and PCNA were normally localized only in the synovial membrane of wild type TMJs. The numbers of immunoreactive cells were extensively larger in the carrageenan-injected synovial membranes exhibiting excessive folding, and smaller in the hyaluronan-injected synovial membranes showing a few folds. These results indicate that a carrageenan injection induced inflammation and cell proliferation especially in the synovial membrane and that hyaluronan relieved the inflammation by decreasing inflammatory molecules in the synovial membrane.ope

Green Urine after Propofol Infusion in the Intensive Care Unit

Urine discoloration occurs in the intensive care unit (ICU) due to many causes such as medications, metabolic disorders, and infections. Propofol is advocated as one of the first line sedatives in the ICU, but it is not well known to the intensivists that propofol can induce urine color change. We experienced two cases of green urine after propofol infusion. Propofol should be warranted as the cause of urine discoloration during ICU stay.ope

Ihh and Runx2/Runx3 signaling interact to coordinate early chondrogenesis: a mouse model

Endochondral bone formation begins with the development of a cartilage intermediate that is subsequently replaced by calcified bone. The mechanisms occurring during early chondrogenesis that control both mesenchymal cell differentiation into chondrocytes and cell proliferation are not clearly understood in vertebrates. Indian hedgehog (Ihh), one of the hedgehog signaling molecules, is known to control both the hypertrophy of chondrocytes and bone replacement; these processes are particularly important in postnatal endochondral bone formation rather than in early chondrogenesis. In this study, we utilized the maternal transfer of 5E1 to E12.5 in mouse embryos, a process that leads to an attenuation of Ihh activity. As a result, mouse limb bud chondrogenesis was inhibited, and an exogenous recombinant IHH protein enhanced the proliferation and differentiation of mesenchymal cells. Analysis of the genetic relationships in the limb buds suggested a more extensive role for Ihh and Runx genes in early chondrogenesis. The transfer of 5E1 decreased the expression of Runx2 and Runx3, whereas an exogenous recombinant IHH protein increased Runx2 and Runx3 expression. Moreover, a transcription factor Gli1 in hedgehog pathway enhances the direct induction of both Runx2 and Runx3 transcription. These findings suggested that Ihh signaling plays an important role in chondrocyte proliferation and differentiation via interactions with Runx2 and Runx3ope

An Immune-compromised Method for Tooth Transplantation Using Adult Bone Marrow Stromal Cells and Embryonic Tooth Germ

Tooth transplantation using autogenic adult teeth or embryonic tooth germs is the one of best treatments for replacement of missing teeth, but there are limitations in the accessibility. Isogenic or xenogenic tooth transplantation has been failed because of the immune rejection response occurring in the periodontal ligament of transplanted tooth. In this study, by utilizing the recombination between mouse embryonic tooth germ and mouse adult bone marrow stromal cells, we tried to replace the periodontal tissues such as periodontal ligament and alveolar bone with adult bone marrow stromal cells. At four weeks after the transplantation of the recombinant into a kidney, adult bone marrow-derived cells cells were observed in the periodontal ligament and alveolar bone. This result indicates that adult bone marrow stromal cells can participate in the formation of periodontal tissues. If these tooth and periodontal tissues are transplanted into host who donates adult bone marrow stromal cells, adult bone marrow-derived cells will be regarded as host cells, and immune rejection response will not occur in these cells. Therefore, it is suggested that recombination between adult bone marrow stromal cells and embryonic tooth germ is a good candidate method using xenogenic tooth germ for replacement of missing teeth in human by replacing cells in periodontal tissues with human adult bone marrow stromal cells.ope