Bulletin Autumn‧Winter 2004

The Department of Clinical Oncology set up in 2003 a service dedicated to the prevention and management of lymphedema in breast cancer. The service takes a multidisciplinary approach and comprises regular arm exercise, a patient support g r o u p, and a L ymp h e d ema C l i n ic for those requiring complex physical therapy. The department has also begun research studies on the risk factors of lymphedema and the quality of life of patients undergoing breast cancer t r e a t me n t. H e a l th i n f o r m a t i on on Chinese populations w i l l be collected to provide relevant data for d e v e l o p i ng an evidence-based a nd feasible model of prevention and management. Medical Research Researchers Solve Mystery of Long-term Memory R esearchers at the Chinese University, i n collaboration w i th the National Institutes of Health (NIH) and Cornell University in the US, found that a protein called brain-derived neurotrophic factor (BDNF) is crucial to the formation of long-term memory. BDNF is well k n own as a trophic factor for neuron survival. The d i s c o v e ry s o l v ed the l o n g - s t a n d i ng mystery of what converts short-term memory to l o n g - t e rm memo r y. The results we re published in Science on 15th October 2004. The researchers of the study, by applying electrophysiological techniques on normal and gene k n o c k - o ut m i c e, s h ow that i n the h i p p o c amp u s, a b r a in area i mp o r t a nt for memo ry f o rma t i on, BDNF is the on ly key protein required for the f o rma t i on of long- t e rm memo r y. T h ey also f o u n d that the synthesis of the active f o r m of B D NF is critically dependent on a seemingly unrelated enzyme system k n own as tPA/plasmin. This may have implications for further research on the mechanism of long-term memory function. The study was mainly carried out by Ms. Petti Pang (photo) who, at the time, was a Ph.D. student at the Department of Physiology at CUHK, under the supervision of Prof. Yung Wing Ho, associate professor in the Department of Physiology and one of the study's authors. Ms. Pang used only 12 months to solve the mystery of long-term memory formation. The f i n d i n gs also ha ve i n t e r e s t i ng implications for the mechanism of forgetting — the reverse of memorization. The research team is n ow studying specific hypotheses on this issue. Important Breakthrough in Research on Sperm Maturation Prof. Chan Hsiao Chang announcing the mystery of sperm maturation on 3rd May 2004 S perms do not intrinsically possess the ability to sw im or fertilize eggs. They acquire these abilities t h r o u gh a process called sperm ma t u r a t i on i n the epididymis situated next to the testes. H o w sperm matures in the epididymis has been puzzling to scientists despite nearly four decades of research. A recent study conducted by the University's Epithelial Cell Biology Research Centre in collaboration w i th the Shanghai Institute of Biochemistry and Cell Biology of the Chinese Academy of Sciences reveals the first secret of sperm maturation. It has been f o u nd that Bin1b, a β -defensin gene f o u nd i n the head region of the epididymis, can attach itself to the sperm head and induce progressive sperm motility in originally immotile immature sperm. News in Brief 71