Annual Report 2012–13

24 開拓人類知識的版圖 糖核酸），如果不能正確傳送遺傳密碼， 會導致這不治之症。 人體內有數以萬計的蛋白質，每一個都有特 定的結構和功能，以調節人體機能。 RNA 指 示核糖體把各個氨基酸合成，以形成蛋白 質。陳教授與來自生物化學、遺傳學、細胞 生物學和神經科學的研究人員組成團隊， 以果蠅及小鼠為研究模型，並研究病患者 細胞樣本，發現某些具毒性的小腦萎縮症 RNA 分子，會阻止名為「核仁素」的蛋白質 在核仁（細胞核內負責製造核糖體的特殊 區域）內與染色質結合，這種稱為「核仁應 激」的現象，最終會引發小腦內出現過度的 細胞凋亡，引致小腦萎縮症。 研究結果刊載於 2012 年 8 月 14 日的全球權威 科學期刊《美國國家科學學院院刊》。 靈魂之窗窺探隱患 賽馬會公共衞生及基層醫療學院副院長兼 生物統計學部主任徐仲 金 英教授開發出一套 演算法，供評估腦血管情況和中風風險的自 動診斷系統之用。與徐教授共同研發的，包 括專長財經和生物資訊的生物統計學家李 作為博士，以及徐教授指導的博士研究生、 致力透過檢查血管病變防範中風的眼科醫 生李青。 患糖尿病達十年以上的人，超過八成會有 糖尿病視網膜病變，即俗稱「糖尿上眼」。 現時，糖尿病視網膜病變篩查屬於常規檢 查，但由於專科人手不足，醫生判斷互異， 等候結果時間太長，成本高昂，成效受到 影響。 研究團隊戮力尋找方法，把視網膜的模擬 影像轉換成可量化及可分析的數據。首先要 解決的是找出視神經盤（俗稱「盲點」，感 光的神經節細胞軸突匯集成視神經，並由 該處離開眼球連接大腦）的準確位置。團隊 也研發了一套比現成辦法更切合本身需要 的方法。 team have unveiled that the failure of RNA (Ribonucleic acid), a form of nucleic acid that has the essential roles of transmitting genetic information contained in DNA (Deoxyribonucleic acid) and to synthesize proteins, to transmit genetic code properly is a cause of this incurable disease. There are tens of thousands of proteins in the human body, each with their own structures and functions that regulate bodily functions. RNA provides instructions for ribosomes to combine individual amino acids to form proteins. Professor Chan and his team of collaborators from such diverse fields as biochemistry, genetics, cell biology, and neuroscience have been working diligently to answer the question using both experimental models, including fruit fly and mouse, and SCA patient cell samples. They discovered that certain toxic SCA RNA molecules would prevent a protein named ‘nucleolin’ from binding with ‘chromatin’ inside the nucleolus, a special region in the cell nucleus responsible for producing ribosomes. Known as ‘nucleolar stress’, this phenomenon eventually triggers excessive apoptosis (i.e., programmed cell death) in the cerebellum and leads to the development of SCAs. His findings were published in the 14 August 2012 issue of the Proceedings of the National Academy of Sciences of the United States of America . Automatic Retinal Image Analysis System Professor Benny Zee, associate director and professor at the Jockey Club School of Public Health and Primary Care and head of the Division of Biostatistics, CUHK, has developed an algorithm for an automatic diagnostic system for cerebral vessel conditions and evaluation of the risk of stroke. This grew out of a collaboration with Dr. Jack Lee, a biostatistician, and Dr. Li Qing, an ophthalmologist and a PhD student of Professor Zee’s who set out to identify vascular diseases before stroke happens. Up to 80% of all diabetics of over 10 years would develop diabetic retinopathy (DR) which is damage to the retina caused by diabetes mellitus, with a concomitant higher chance of suffering stroke at a later stage. DR screening has become a standard procedure in diabetic care but its effectiveness is hampered by several factors: not enough specialists to administer the screening, human variability in diagnosis, long waiting time for the result, and high cost.