Objective To analyze CT features of the pulmonary segment lesions.Methods The CT findings of 88 patients with pulmonary segment lesions were reviewed.The diseases included chronic pneumonitis(n=30),tuberculosis(n=24),lung cancer(n=34),all proved pathologically.Results Wedge-shape or cone-shape of lesions was demonstrated in most of cases.In chronic pneumonitis,the border of lesion was depression or straight without hilar mass and bronchus obstructed.Most lesion was isodensity and the air bronehogram could be found in some cases.In tuberculosis,the border was irregular or hazy with different density inside the lesion(cavity,calcification,bronchieetasis).Satellite-lesion and thickening of the pleura nearby were found commonly.In lung cancer,the hilar mass and pot obstructed bronchus were the characteristic,with the border evagination in some cases.According to the above,82% of the cases were diagnosed correctly.Conclusions Some relative specific CT manifestation existed in the pulmonary segment lesions caused by chronic pneumonitis,tuberculosis and lung cancer.But the CT of some patients were similar to each other,of which diagnosis must be based on pathology.

Objective To analyze the image findings of renal tuberculosis and evaluate the merits and disad vantages of various imaging diagnostic methods, then choose the most sensitive one. Methods The KUB, IVP, AP and CT findings of 48 patients with renal tuberculosis which had been convinced by operations were evaluated and compared. Results The diagnosis rates of KUB and IVP were 41.7% (20/48), AP of 62.5 % (10/16), CT of 100 % (48/48). The characteristic findings of CT were multiple low density lesions, with "flower petals" shape gath-ered in sections. Conclusion CT has a great value for diagnosing renal tuberculosis.

Objective To investigate the effects of lowdose ionizing radiation (LDIR) on oxidative stress and damage repair in human bronchial epithelial (HBE) cells. Methods HBE cells were divided into 0, 50, 100, and 200 mGy groups, and cultured for 24 and 48 h after X-ray irradiation, respectively. The cell viability, levels of glutathione (GSH), malondialdehyde (MDA), and 8-hydroxy-2’-deoxyguanosine (8-OHdG), and transcriptional levels of DNA damage repair genes PPP2R2D and TP53 were measured. Results At 24 h after irradiation, there was no significant difference in the cell viability between the dose groups and the control group (P > 0.05); all dose groups had significantly increased MDA level, dose-dependently decreased GSH level, dose-dependently increased 8-OHdG level, and significantly increased mRNA level of PPP2R2D gene (all P < 0.05); the mRNA expression level of TP53 gene was significantly increased in the 50 mGy group (P < 0.05). At 48 h after irradiation, there were the highest cell viability, significantly decreased MDA and 8-OHdG levels, and significantly increased mRNA expression levels of PPP2R2D and TP53 genes in the 50 mGy group compared with the control group (all P < 0.05); the GSH level in the 100 mGy group was significantly increased (P < 0.05). Conclusion LDIR, especially radiation at 50 mGy, can affect the oxidative-antioxidant level in HBE cells and the transcript-level differential expression of DNA damage repair genes.

Background Radiation-induced liver damage is a major complication for primary liver cancer and other upper abdominal tumors during radiation therapy. The early biological effects of radiation-induced liver damage at different doses of radiation and its mechanisms of action have not yet been elucidated. Objective To establish X-ray-induced radioactive mouse liver damage model and explore the level of oxidative stress and its correlation with nuclear factor-κB (NF-κB) and transforming growth factor-β1 (TGF-β1). Methods A total of 24 male C57BL/6J mice aged 6 weeks were randomly divided into 4 groups (control, 0.8 Gy, 1.6 Gy, and 4 Gy), with 6 mice in each group. X-rays irradiated the whole body of mice singly in each dose group. At 24 h after radiation, histopathological changes in mouse liver were evaluated; peripheral blood cell count, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, as well as liver tissue superoxide dismutase (SOD) activity, malondialdehyde (MDA) level, reduced glutathione (GSH) level, and 8-hydroxy-2′-deoxyguanosine (8-OHdG) level were measured; real-time fluorescence quantitative PCR was used to detect liver tissue NF-κB p65 and TGF-β1 mRNA expression levels; the correlations of oxidative stress indicators with NF-κB p65 and TGF-β1 mRNA expression levels were analyzed by Pearson correlation. Results Compared with the control group, at 24 h after different doses of X-ray radiation, early injury-related histopathological changes were observed in liver, and the serum levels of AST and ALT were significantly increased in the 4 Gy group (P<0.05); the numbers of peripheral blood leukocytes and lymphocytes were decreased in the radiation exposure groups (P<0.05), showing a decreasing trend with increasing radiation doses; the levels of liver oxidative stress indicators (MDA, SOD, and GSH) in exposed mice were significantly increased (P<0.05), showing an increasing trend with increasing radiation doses. The liver 8-OHdG were significantly increased in the 1.6 Gy and 4 Gy groups compared with the control and the 0.8 Gy groups, respectively (P<0.05). The NF-κB p65 and TGF-β1 mRNA expression levels in the liver of mice were significantly increased in the 1.6 Gy and 4 Gy groups compared with the control group (P<0.05). The TGF-β1 mRNA expression level also exhibited an increasing trend with increasing radiation doses. The results of correlation analysis showed that the levels of MDA, SOD, GSH, and 8-OHdG in liver tissues were significantly and positively correlated with the expression levels of NF-κB p65 and TGF-β1 mRNA (P<0.05). Conclusion X-rays of various doses can affect the degree of liver injury, peripheral blood cell count, serum levels of AST and ALT, and liver oxidative stress levels in mice. The level of oxidative stress induced by X-ray is positively correlated with NF-κB and TGF-β1 in liver tissues, and it may participate in the process of radiation-induced liver injury.