Objective To investigate the effect of PEP-1-heme oxygenase-1 (PEP-1-HO-1) fusion protein transduction on hypoxia-reoxygenation (H/R) injury in rat H9c2 cells. Methods After construction of the prokaryotic expression plasmid pET15b-PEP-1-hHO-1 containing the human heme oxygenase-1 gene, it was then transformed to make PEP-1-HO-1 fusion protein express. The H9c2 cells were cultured in high-glucose Dulbecco's modified Eagle's medium (DMEM) supplemented with 15% fetal bovine serum and randomly divided into 4 groups (n = 4 each): control group (group C), H/R group, low-concentration fusion protein group (group L-HO), and high-concentration fusion protein group (group H-HO). The cells were exposed to 22 h of hypoxia followed by 8 h of reoxygenation. PEP-1-HO-1 fusion protein was added to the culture medium with a final concentration of 1.0 μ mol/L (group L-HO) or 2.0 μmol/L (group H-HO) before hypoxia. The cells and supernatant of the culture medium were collected after reoxygenation to determine the activity of lactate dehydrogenase (LDH) in the supernatant and the content of malondialdehyde (MDA) and activity of superoxide dismutase (SOD) in the cells. Results The SOD activity was significantly lower, while the MDA content and LDH activity were significantly higher in group H/R, L-HO and H-HO than in group C (P ＜0.05). The SOD activity was significantly higher, while MDA content and LDH activity were significantly lower in group L-HO and H-HO than in group H/R, and in group H-HO than in group L-HO ( P ＜ 0.05). Conclusion PEP-1-HO-1 fusion protein transdution can protect H9c2 cells against H/R injury in rats.

Objective To evaluate the effects of heme oxygenase-1 (HO-1) mediated by cell penetrating peptide PEP-1 on liverinjury induced by intestinal ischemia/reperfusion (I/R) in rats.Methods Twenty-four male Sprague-Dawley rats,aged 7-9 weeks,weighing 210-260 g,were randomly divided into 3 groups (n =8 each):sham operation group (group S),intestinal I/R group (group I/R) and PEP-1/HO-1 group (group HO).To establish a model of intestinal I/R,intestines were exteriorized and the superior mesenteric artery was exposed and occluded for 45 min ischemia,and then the clamp was removed for 120 min reperfusion.The PEP-1/HO-1 fusion protein 0.5 mg was injectedvia ihe left iliac vein 30 min prior to ischemia in group HO.The superior mesenteric artery was only exposed but not occluded in group S.At the end of reperfusion,blood samples were collected from the right common carotid artery for measurement of serum aspartate aminotransferase (AST),alanine aminotransferase (ALT) activities.The rats were then sacrificed and livers were removed for microscopic examination and for determination of malondialdehyde (MDA) content and superoxide dismutase (SOD) activity in livertissues.Results Compared with group S,serum AST and ALT activities and MDA content in liver tissues were significantly increased,while SOD activity in liver tissues was decreased in groups I/R and HO (P ＜ 0.05).Compared with group I/R,serum AST and ALT activities and MDA content in liver tissues were significantly decreased,while SOD activity in liver tissues was increased in group HO (P ＜0.05).Liver injury induced by intestinal I/R was significantly attenuated in group HO compared with group I/R (P ＜ 0.05).Conciusioon HO-1 protein mediated by cell penetrating peptide PEP-1 can attenuate liver injury induced by intestinalI/R in rats.

Objective To investigate the effects of heme oxygenase-1 (HO-1) transduced by cell penetrating peptide PEP-1 on renal ischemia/reperfusion (I/R) injury in rats.Methods Eighteen male Sprague-Dawley rats,aged 7-9 weeks,weighing 210-260 g,were randomly divided into 3 groups (n =6 each):sham operation group (group S),renal I/R injury group (group I/R) and fusion protein PEP-1/HO-I + I/R group (group HO).I/R injury was produced by occluding bilateral renal arteries for 45 min followed by reperfusion for 6 h.The fusion protein PEP-1/HO-1 was injected via the left iliac vein 30 min prior to ischemia in group HO.Bilateral renal arteries were only exposed but not occluded in group C.Blood samples were collected from the right common carotid artery at 6 h of reperfusion for determination of serum blood urea nitrogen (BUN) and creatinine (Cr) concentrations.The malondialdehyde (MDA) content,superoxide dismutase (SOD) activity and HO-1 expression in renal tissues were measured.Results Compared with group S,the levels of MDA,serum BUN and Cr were significantly increased,the SOD activity was decreased,and HO-1 expression was up-regulated in groups I/R and HO (P ＜0.05).Compared with group I/R,the levels of MDA,serum BUN and Cr were significantly decreased,the SOD activity was increased,and HO-1 expression was up-regulated in group HO (P ＜ 0.05).Conclusion HO-1 protein can be successfully transduced into renal tissues by PEP-1 and transduced HO-1 protein reduces renal I/R injury by inhibiting lipid peroxidation response.

Objective To investigate the protective effects of heme oxygenase-1 (HO-1) mediated by cell penetrating peptide PEP-1 on myocardium against ischemia/reperfusion (IR) injury in isolated rat hearts. Methods Healthy male SD rats weighing 220-280 g were anesthetized with intraperitoneal pentobarbital. Their hearts were excised and perfused in a Langendorff apparatus with K-H solution saturated with 95%O2-5% CO2 at 37 ℃. Eighteen isolated rat hearts were randomly divided into 3 groups ( n = 6 each): Ⅰ group sham operation (group S);Ⅱ group IR and Ⅲ group PEP-1/HO-1 + IR (group HO-1). The isolated rat hearts were perfused with an oxygena-ted (95% O2-5% CO2 ) K-H solution at 37 ℃ in a Langendorff apparatus and were subjected to 40 min of global ischemia followed by 50 min of reperfusion after 30 min of stabilization. In group Ⅲ (group HO- 1 ) the isolated hearts were perfused with 50 μmol/L PEP-1/HO-1 for 15 min before ischemia. After 50 min of reperfusion, HO-1expression, MDA content and SOD activity in myocardial tissues were determined. The activities of creatine kinase (CK) and lactic dehydrogenase (LDH) in coronary effluent fluid were measured. Results The HO- 1 expression was significanfly higher in HO-1 group than in group IR. IR induced significant increase in MDA content and decrease in SOD activity in myocardium and CK and LDH activities in coronary effluent in group Ⅱ compared with group S. PEP-1/HO-1 significantly attenuated IR-induced changes. Conciusion HO-1 mediated by PEP-1 has protective effects on myocardium ngainst IR injury in rats.

Objective:To investigate the value of chest CT quantitative index in clinical classification and lung injury severity evaluation of COVID-19.Methods:The current study retrospectively analyzed the clinical and CT data of 438 patients with COVID-19 between January 2020 and March 2020 in Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology. The clinical types included common type ( n=146), severe type ( n=247) and critical type ( n=45). The chest CT indexes of all patients were quantitatively analyzed by artificial intelligence (AI) deep learning, including whole lung volume, CT lung opacification, ground glass opacification volume (GGO volume; CT value<-300 HU), solid opacification volume (SO volume; CT value ≥-300 HU) and the ratio of volume to the whole lung volume, the ratio of SO volume to GGO volume (SO volume/GGO volume). Kruskal-Wallis test was used to conduct statistical analysis of the differences in quantitative parameters among clinical types, and multiple ordered logistic regression was used to analyze the correlation between quantitative parameters and clinical types. Results:Among the 438 patients diagnosed with COVID-19, severe and critical patients were older ( P<0.05), and most of the critical patients were male ( P<0.05). The main clinical manifestations of all clinical types were fever, followed by cough, fatigue, chest tightness, dyspnea, gastrointestinal symptoms and so on. GGO volume was the main CT manifestation of all the three clinical subtypes. The whole-lung opacification volume, GGO volume, SO volume and their proportions in whole-lung volume significantly increased from common, severe to critical types (all P<0.05). SO volume/GGO volume increased with the severity of clinical type [common type 0.12 (0.03, 0.34), severe type 0.29 (0.11, 0.59), critical type 0.61 (0.39, 0.97)]. Multiple ordered logistic regression analysis showed that whole-lung opacification volume (OR=1.009), SO volume/GGO volume (OR=1.866), GGO volume (OR=1.008) and SO volume (OR=1.016) had a significant positive effect on the severity of clinical typing ( P<0.01). Conclusion:Quantitative indicators of chest CT based on deep learning algorithm (SO volume, GGO volume, SO volume/GGO volume) are closely related to the clinical severity of COVID-19.

Objective:To explore the feasibility of cardiac T 2 weighted dark blood sequence (T 2W-DB) based on artificial intelligence assisted compression-sensing(ACS) in clinical cardiac MR examination, compared with the conventional cardiac fast spin-echo T 2W-DB sequence. Methods:A total of 38 patients referred for cardiac MR examination in Tongji Hospital were enrolled prospectively from August to December 2021. The conventional T 2W-DB scan and the single-shot ACS T 2W-DB scan were acquired at continuous short-axial slices covering the whole left ventricle in all patients, and the acquisition time of each scan was recorded. The image quality of the two sequences was evaluated by the objective quantitative parameters and the subjective scoring methods, respectively. The signal to noise ratio (SNR), the contrast to noise ratio of the interventricular septum to blood pool (CNR), and the sharpness of the images were calculated. The subjective scoring was to evaluate the overall image quality, the effect of blood pool suppression, the visibility of right ventricular free wall, left ventricular free wall, and interventricular septum with a 5-point Likert scale. The intraclass correlation coefficient and Kendall W were calculated to evaluate the interobserver agreement of the objective quantitative parameters and subjective scoring. The paired t-test or Wilcoxon test was used to compare the difference in acquisition time, objective quantitative parameters and subjective scoring between the conventional T 2W-DB and the single-shot ACS T 2W-DB. Results:The inter-observer agreement between the single-shot ACS T 2W-DB and conventional T 2W-DB was good in all the objective quantitative parameters and subjective scoring of image quality ( P<0.05 for all). Compared with conventional T 2W-DB, acquisition time of single-shot ACS T 2W-DB was remarkably shortened [(85.8±14.7) s vs. (16.9±3.0) s, t=35.42, P<0.001]. Compared with SNR (66.4±29.0) and CNR(61.8±28.6) of conventional T 2W-DB, single-shot ACS T 2W-DB had significantly higher SNR(110.8±36.8, t=-8.13, P?0.001) and CNR(88.2±31.1, t=-5.89, P?0.001). Compared with conventional T 2W-DB, single-shot ACS T 2W-DB had better blood pool inhibition effect (4.6±0.6 vs. 4.7±0.5, Z=-2.64, P=0.008). There was no significant difference in overall image quality, visibility of right ventricular free wall, left ventricular free wall, and interventricular septum between the two sequences( P>0.05 for all). Conclusions:In cardiac MR examination, compared with the conventional T 2W-DB sequence, the single-shot ACS T 2W-DB sequence can significantly shorten the acquisition time and obtain better image quality.