SARS is associated with epithelial-cell proliferation and an increase in macrophages in the lung. The presence of haemophagocytosis supports the contention that cytokine dysregulation may account, at least partly, for the severity of the clinical disease. The case definition of SARS should acknowledge the range of lung pathology associated with this disease.

PC extracts at 8 g/kg/day might cause fetal toxicity and maternal liver damage in mice, although it did not cause typical malformation and ESC's cytotoxicity in this experiment. Our data suggested that high dosage and long-term administration of PC preparations may not be safe for pregnant women.