The regulatory effects of niacinamide (Nia) on intervertebral disc (IVD) aggrecanin vitro was investigated. Chiba's 10 ng/mL interleukin-1 (IL-1)-induced rabbit IVD degeneration modelin vitro was established. 0. 5, 0. 25 and 0. 05 mg/mL Nia was added to normal and degenerated IVDs for intervention. On the first and second week after intervention, safranin O-fast green staining intensity and glycosaminoglycan (GS) content were measured. The expression of aggrecan core protein was detected by RT-PCR. The results showed: (1) After treatment with 0.5 mg/mL Nia for one week, the GS content in nucleus pulposus (NP) was increased by 44.8%, as compared with control group (P<0.01); The GS content in IL-1 induction groups was increased with the increase of Nia concentrations: After treatment with 0.5 mg/mL for one week, the GS content in NP was increased by 68.3 % as compared with control group (P<0.01). After two weeks, GS content in NP and fibrous rings was still higher than in control group at the same period (P<0.01) and untreated group (P<0.01). (2) Safranin O-fast green staining revealed that with the increase of Nia concentrations staining density in NP and fibrous rings was increased and histological structure damage to IVDs by IL-1β was alleviated. (3) RT-PCR showed that the expression of core protein gene in IL-1β-induced degenerated IVDS was increased with the increase of Nia concentrations. It was concluded that under conditionsin vitro, Nia could up-regulate the expression of aggrecan in IVDs and protect IVDs from IL-1β-induced degeneration at least partially, which offers a potential choice for IVD degeneration clinical therapy.

An experimental animal model of malignant soft-tissue tumor was established to investigate the applied value of multi-slice spiral CT perfusion imaging preliminarily. Ten New Zealand white rabbits which were implanted with VX₂ tumor in either proximal thigh were subjected to CT plain scan and perfusion scan two weeks later respectively, the the original perfusion images were transmitted to AW4.0 Workstation. The functional maps and perfusion parameters including blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface (PS) were computed and analyzed. All the values of BF, BV and PS in VX₂ soft-tissue tumors were obviously higher while the MTT-values were lower than those in the normal muscular tissues significantly. It was suggested that multi-slice spiral CT perfusion imaging is an accurate, convenient and relatively safe functional imaging technique, and can give a quantitative assessment to angiogenesis and blood perfusion of soft-tissue tumors.