[Glial fibrillary acidic protein mutation in a Chinese girl with infantile Alexander disease].

OBJECTIVE: To investigate the molecular basis of infantile Alexander disease in a Chinese patient, which may yield useful information for further genetic counseling. METHODS: DNA sequencing analysis and restriction endonuclease analysis were used to detect the mutation of glial fibrillary acidic protein (GFAP) gene in a patient with clinically diagnosed Alexander disease, in her parents and in 50 healthy controls. RESULTS: A 249C>T (R79C) mutation was identified in the exon 1 of the GFAP gene but not in her parents and the controls. CONCLUSION: The study on mutation of GFAP gene in Chinese patients with Alexander disease has never been reported previously. The mutation analysis of GFAP gene can provide valuable information for the diagnosis of Alexander disease and can serve as a reliable method of prenatal diagnosis for the family.

[Development of self-generating lower body negative pressure device].

OBJECTIVE: To develop a kind of self-generating lower body negative pressure device. METHOD: The device consists of a flexible bellows, reinforced by several steel rings and sealed by gasproof adhesive plaster. An adjustable valve, a one-way flap valve, shoulder straps and handles are incorporated on the top of the bellows. The user's lower body was contained in the bellows. As the user's legs were extended, the bellows was elongated and the air pressure in it decreased. RESULT: Negative pressures of -58, -46, -38 and -26 mm-Hg respectively was created with the adjustable inlet valve completely closed, one-quarter open, half open, or fully open. CONCLUSION: This self-generating lower body negative pressure device combines exercise and LBNP into one thing and is safe and easy to use. It might be used in preventing cardiovascular deconditioning during spaceflight or for anti-G training of pilots.