Objective To investigate the radiation induced pulmonary fibrosis with a dose-response mouse model, based on the CT image changes of pulmonary fibrosis.Methods Female C57BL6 mice aged 8-10 weeks were randomly divided into 20 Gy or escalated doses of X-ray whole thoracic irradiation ( WTI) groups. CT scan was performed at different time points before and after radiation. The average lung density and lung volume changes were obtained by three-dimensional segmentation algorithm. After gene chip and pathological validation, the parameters of CT scan were subject to the establishment of logistic regression model. Results At the endpoint of 24 weeks post-irradiation, the lung density in the 20 Gy irradiation group was (-289.81± 12.06) HU, significantly increased compared with (-377.97± 6.24) HU in the control group ( P<0.001) . The lung volume was ( 0.66±0.01) cm3 in the control group, significantly larger than ( 0.44±0.03) cm3 in the irradiated mice ( P<0.001) . The results of quantitative imaging analysis were in accordance with the findings of HE and Mason staining, which were positively correlated with the fibrosis-related biomarkers at the transcriptional level ( all R2=0.75, all P<0.001) . The ED50 for increased lung density was found to be ( 13.64± 0.14) Gy ( R2=0.99, P<0.001) and ( 16.17± 4.36) Gy ( R2=0.89, P<0.001) for decreased lung volume according to the logistic regression model. Conclusions Quantitative CT measurement of lung density and volume are reliable imaging parameters to evaluate the degree of radiation-induced pulmonary fibrosis in mouse models. The dose-response mouse models with pulmonary fibrosis changes can provide experimental basis for comparative analysis of high-dose hypofractioned irradiation-and half-lung irradiation-induced pulmonary fibrosis.

Obesity is a global public health problem that imposes a heavy economic burden on society. The current main strategies for treating obesity include lifestyle interventions, pharmacological treatments, endoscopic treatments and metabolic surgery. With the development of medical technology, weight reduction by intragastric occupancy devices represented by intragastric balloons and intragastric capsules are gradually emerging. Intragastric balloons are used to reduce weight by occupying the volume of the stomach with balloons filled with different volumes of gas or liquid, among which ReShape, Orbera, Obalon, Elipse and Spatz balloons are gradually used in patients with mild to moderate obesity due to their non-invasive, high safety and reusable advantages. Intragastric capsules are recommended in overweight and obese patients for weight loss through hydrogels with transient superabsorbent swelling properties and completely noninvasive. Both approaches achieve weight loss by limiting gastric volume, increasing satiety and reducing food intake. Despite the presence of adverse gastrointestinal events associated with nausea, vomiting, and abdominal distention, they offer new ideas for the non-invasive clinical treatment of obesity.
Humans ; Capsules ; Weight Loss ; Obesity/surgery* ; Overweight ; Stomach/surgery*