The Application Value of Gemstone Spectral Imaging (GSI) Combined with an 80 mm Wide-body Detector in Head-neck CTA.

OBJECTIVE: This study aims to investigate the value of gemstone spectral imaging (GSI) combined with an 80 mm wide-body detector in head-neck CTA. METHODS: Ninety patients with head-neck CTA were prospectively selected and randomly divided into a control group and a test group, with 45 patients in each group. The control group was scanned conventionally. With a tube voltage of 100 kVp and detector width of 40 mm, a 70 ml contrast agent was injected at a flow rate of 5.0 ml/s. The test group used GSI. With a tube current fixed of 445 mAs and a detector width of 80 mm, the contrast agent was injected at a flow rate of 3.5 ml/s and 0.6 ml/kg body weight, and the 55 keV virtual monoenergetic images (VMIs) were automatically reconstructed. Finally, the target vessel CT values, background noise (BN), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), subjective scores, contrast agent dose, CT dose index volume (CTDIvol), and dose length product (DLP) were recorded. The DLP was converted to the effective dose (ED). RESULTS: The target vessel CT values, BN, SNR, CNR, and subjective scores of the two groups were not statistically significant (all P > 0.05), and the image quality of both groups was the same and met the diagnostic requirements. The contrast agent dose and effective dose (ED) in the test group were approximately 44% and 26% lower than that of the control group, respectively (all P < 0.05). CONCLUSION: In head-neck CTA examination, the Revolution CT GSI combined with an 80 mm wide-body detector can reduce the contrast agent dose and radiation dose while ensuring image quality.

Chronic exposure to ammonia induces oxidative stress and enhanced glycolysis in lung of piglets.

Ammonia is one of the major environmental pollutants in the pig industry that seriously affects the airway health of pigs. In this study, we aimed to investigate the metabolic profiling changes of piglets' lung tissue after the exposure of 0 ppm (CG), 20 ppm (LG) and 50 ppm (HG) ammonia for 30 days. Compared with the control group, the obvious lung lesions were observed in HG, including interstitial thickening, inflammatory cell infiltration and focal hemorrhage. The significantly increased content of malondialdehyde in HG, combined with the significantly decreased mRNA expression of antioxidase and inflammatory-regulators in exposure groups, implied that ammonia exposure induced oxidative stress and diminished the anti-inflammatory response in lung tissues. Metabolomic analyses of lung tissues revealed 15 significantly altered metabolites among the three groups including multiple amino acids, carbohydrates and lipids. The accumulation of succinic acid, linoleic acid and phosphorylethanolamine and consumption of glucose, quinolinic acid and aspartic acid in ammonia exposure groups, indicated that energy supply from glucose aerobic oxidation was suppressed and the glycolysis and lipolysis were activated in lung tissues induced by chronic ammonia exposure.