This paper describes the value of positron emission tomography(PET) in diagnosis and staging of lung cancer. Current status and prospect of positron emission tomography in mainland of China were briefly discussed: PET examination cost has not been covered by national health care system at present. Numbers of PET should be increased within limits and its development should keep balance with economic and social development level. It is necessary to have more nuclear medicine physicians training and cooperation between PET physicians and clinical referring physicians.

Objective To investigate the expression of glucose transporter 3(GLUT 3) transcription level at different ischemic time in rats' focal cerebral ischemic penumbra and core of cortices.Methods Focal ischemic models of middle cerebral artery occlusion (MCAO) in rats were made by inserting nylon surgical thread. Brain samples were harvested from ischemic penumbra and core of cortices. The change of GLUT 3 mRNA was assessed by RT PCR.Results GLUT 3 mRNA in the penumbra regions slightly increased at 3 h after ischemia, and reached a peak at 24 h, in 96h following ischemia it came back to the normal level. As for ischemic core regions, GLUT 3 mRNA had a short time increase at 3 h after ischemia, and then rapidly decrease to the low level. Conclusion GLUT 3 mRNA expression was notably up regulated in the penumbra regions after focal cerebral ischemia,it may be a protective reaction against ischemic injury.

BACKGROUNDOwing to the limitation of monolayer tumour cells or transplanted tumor in radiation biology, multicellular spheroid (MTS) as a model of entity tumor had a wide range of application. This research aims to study the growth characteristics of A549 lung adenocarcinoma MTS so as to choose the best ones to perform experiments.

METHODS1.75×10⁷ A549 cells in 35mL were transfered into the 100mm incubator sealed with 2% agarose to have a rotating culture with 60r/min. After 40 hours every MTS was transfered into each of the 96 wells of multi-well plates coated with 2% agarose to have a static culture.

RESULTSDuring the rotation stage the MTS was round, the size was uniform, and the conjunction between cells was loose. After about 10 days of static culture, when the diameter of MTS at 429 to 570 μm the conjunction was close. After 26.5 days of static culture, the diameter of MTS became 1358.5 μm which could not be used for experiment. Observed under electron microscopy the cells in the MTS grew well without any apoptosis and necrosis. The cell cycle of MTS was dominated by G0 and G1 stage.

CONCLUSIONSCombination of rotating and static culture is a simple method to produce MTS which has similar growth characteristics with entity tumor and is best suitable for experiment research when the diameter is about 500 μm.