Newsletter No. 279

EYE CAMPUS Killing Mosquitoes by Luring Them to Lay Eggs T h e University's luxuriant campus is something to be proud of yet lush I greenery also provides optimal breeding grounds for mosquitoes. Mosquitoes are not only a nuisance; they are the prime culprits for spreading diseases such as Dengue fever and malaria. To protect the health of campus members, the University is committed to combating these potentially lethal creatures. Beginning in mid-2005, ovitraps have been placed throughout the campus to identify mosquito breeding black spots for the sake of fighting mosquitoes more strategically. The University Safety and Environment Office is responsible for placing ovitraps and processing the data received. Mr. Lam Shi-kai, safety manager of the office, said, 'We place ovitraps at 15 different locations on campus, for seven days at a stretch. We then tally the number of pupae and change locations monthly.' The ovitraps are provided by the Department of Food and Environmental Hygiene. They are black cylinders of 200 ml each and come with a brown paddle. The paddle is dipped in water to lure female mosquitoes to lay eggs. Mosquito pupae usually take nine days to develop so the ovitraps are retrieved after seven days. Mr Lam said, 'Ovitraps are placed at black spots where Aedes pupae or pupae of other mosquitoes have been found. We will continue to place ovitraps to monitor the situation; at the same time, we will notify staff of the Estates Management Office to keep grass short and trimmed, clear away stagnant water and spray insecticide.' He added that it is hard to distinguish between Aedes and other mosquitoes. His office has sent a staff member who is on loan from the Department of Microbiology to undergo training at the Department of Food and Environmental Hygiene to learn how to differentiate Aedes from regular mosquitoes. 'Aedes mosquitoes are characterized by white stripes on their bodies but these are barely visible to the naked eye. Ovitraps also attract other insects to lay eggs. Therefore we have to magnify the larvae under a stereomicroscope for proper identification.' Reviewing the data of the past year, Mr. Lam remarked. The campus is inhabited by many species of mosquitoes. It is hard to say which predominate but luckily the Culex mosquito which transmits Japanese encephalitis is rarely found. Most pupae were recorded in August and September. These were also the busiest months for EMO staff. During the orientation camp for new students, especially, measures for eliminating mosquitoes were stepped up.' Mr. Lam calls upon members of the University to notify the EMO by phone at 2609 6666 If they ever stumble upon favourite mosquito haunts or puddles of stagnant water. 'A Tooth for an Eye' New Hope for Corneal Blindness O steo-Odonto Keratoprosthesis (OOKP) or ' To o t h - i n - Ey e ', pioneered by Prof. Benedetto Strampelli in Italy in the 1960s, is a procedure which aims at restoring sight to patients with the most severe type of corneal and ocular surface diseases, for whom other treatments would not be useful. It involves creating a support for an artificial cornea from the patient's own tooth and the surrounding bone. Prof. Giancarlo Falcinelli of Italy, a student of Prof. Strampelli, has refined and improved the procedure. The results have been encouraging and many patients can still keep their vision since their operations more than 20 years ago. Due to its complexity, the procedure is at present performed by fewer than 10 centres in the world. The Department of Ophthalmology and Visual Sciences of The Chinese University has started this procedure in Hong Kong and in Shantou at the Joint Shantou International Eye Centre of Shantou University and The Chinese University of Hong Kong (JSIEC) in April 2005, with the help of Prof. Falcinelli and his son Dr. Johnny Falcinelli. Like the lens of a camera, the cornea is transparent and can focus light rays on the retina. Degeneration, trauma, chemical burn, infection, inflammation, and allergy are some of the common conditions that can affect the cornea, resulting in scarring and opacities, which result in poor vision. In some s i t ua t i ons, med i cal treatments (e.g. with eye-drops) are enough to clear cloudy vision. However, in ce r t a in cases whe re med i cal treatments fail, surgery is the next step —corneal transplantation. Yet, in some eyes, the damage is so severe that corneal transplantation does not work. To p r o v i de the pa t i ent w i t h useful vision, an artificial cornea or 'keratoprosthesis' is used. The artificial cornea is made of hard plastic. To fix the plastic prosthesis in place, tissues from the patient's own body are used. The tooth is ideal because it has a hard part to which the cylinder can be fixed and also it resides in the mouth where it co- exists with soft tissues, as in the eye. OOKP has a success rate of 80-90%. Since April 2005, five patients have completed both the stage-one and stage- two procedures. 'We estimate that the list of patients would be more than a hundred in Hong Kong and thousands in China,' said Prof. Dennis Lam, cha i rman of the Depa r tment of Ophthalmology and Visual Sciences. For more information on the above, please call the Hong Kong hotline 2637 1343 or the mainland hotline 86-0754- 8393575 during office hours. (From left) Dr. Johnny Falcinelli, Prof. Giancarlo Falcinelli, Prof. Srinivas K. Rao, Prof. Dennis Lam, Dr. LeeKwing-hong ,and Dr. Alvin L. Young SUPPORT FOR F o u r RESEARCH-RELATEDEVENTS T he following four research-related events undertaken by faculty members of the University have succeeded in attracting funding support from the Croucher Foundation: • Opportunities and Challenges for Physicists in Quantitative and Systemic Biology (HK$600,000) Person responsible: Prof. Emily Ching Shuk-chi (Department of Physics) • The 4th International UPPSALA Conference on Electron Capture and Transfer Dissociation Mass Spectrometry — Fundamentals and Applications (HK$100,000) Person responsible: Prof. Dominic Chan (Department of Chemistry) • The 3rd Workshop on Network, Coding, and Applications (NetCod 2007) (HK$100,000) Persons responsible: Prof. Raymond Yeung and Prof. Robert Li (Department of Information Engineering) • Conference on Public Health and Evidence-based Decision Making (HK$100,000) Person responsible: Prof. Sian Griffiths (School of Public Health) Vitamin B12 and Folic Acid Prevent Heart Disease and Stroke, Study Finds A therosclerosis (heart attack and stroke) is the most worrying health problem in modern societies. Preventive strategies are currently focused on healthy lifestyles and dietary habits or medications for optimal control of atherosclerosis risk factors including smoking, hypertension, diabetes mellitus, high cholesterol and obesity. Supplementation remains a debatable subject in the prevention of the disease. In a series of studies starting from 1998, Prof. Woo Kam-sang, professor of med i c i ne and t he r apeu t i cs of the University, discovered that long-term vegetarians in Hong Kong and rural Chinese in Shanxi, despite a better blood cholesterol profile, are deficient in vitamin B12 and/or folic acid (micronutrients) and have worse atherosclerosis surrogate markers (endothelial function and intima- media thickness) compared to non- vegetarians or southern Chinese. The research was conducted in collaboration with scholars in mainland China. The research team then conducted a randomized, double-blind and placebo s u p p l eme n t a t i on t r i a l, under the Leungkitwah project, on 180 Yu County farmers or coal-miners in 2004—06, using oral vitamin B12 and folic acid for a year. Co r r e c t i on of such m i c r o n u t r i e nt deficiency was found to significantly improve these atherosclerotic markers. The research team explained the results of the study and how vitamin B12 or folic acid supplementation can prove to be a safe, affordable and cost-effective strategy for primary atherosclerosis prevention in China at a press conference held on 6th May at the Postgraduate Education Centre of the Prince of Wales Hospital. 2 No. 279 19th May 2006