Objective To evaluate the effect of remifentanil preconditioning ( RP ) on intestinal is?chemia?reperfusion ( I∕R) injury in rats and its relationship with opioid receptors. Methods Seventy?two Sprague?Dawley rats, aged 6-7 weeks, weighing 250-280 g, were randomly divided to 9 groups ( n=8 each): sham operation group (S), intestinal I∕R group (group I∕R), RP group, different opioid receptor antagonists groups (N, BNI and CTOP groups), and opioid receptor antagonists + RP groups (N+RP, BNI+RP and CTOP+RP groups) . Intestinal I∕R was produced by clamping the superior mesenteric artery for 1 h followed by 2 h reperfusion in all the groups except group S. RP was induced by 3 cycles of 5 min infusion of remifentanil 0?2 μg·kg-1 ·min -1 followed by 5 min infusion of normal saline before ischemia. Naltrindole (δ?receptor antagonist, 5 mg∕kg) , nor?binaltorphimine (κ?receptor antagonist, 5 mg∕kg) and CTOP (μ?receptor antagonist, 1 mg∕kg) were administered before RP. At 2 h of reperfusion, blood sam?ples were collected from the cardiac apex for determination of serum diamine oxidase ( DAO) activity. Intes? tinal tissues were then removed for microscopic examination. Intestinal damage was assessed and scored ac?cording to Chiu. Apoptosis in intestinal mucosal epithelial cells was detected using TUNEL assay, and ap?optosis index was calculated. The expression of activated caspase?3 in intestinal mucosal epithelial cells was measured by Western blot. Results Compared with group S, the serum DAO activity, Chiu′s score, and apoptosis index were significantly increased, and the expression of activated caspase?3 was up?regulated in I∕R and RP groups ( P<0?05) . Compared with group I∕R, the serum DAO activity, Chiu′s score, and ap?optosis index were significantly decreased, and the expression of activated caspase?3 was down?regulated in RP, BNI+RP and CTOP groups (P<0?05), and no significant change was found in the parameters men?tioned above in N, N+RP, BNI and CTOP+RP groups (P>0?05). Compared with group RP, the serum DAO activity, Chiu′s score, and apoptosis index were significantly increased, and the expression of activa?ted caspase?3 was up?regulated in N+RP and CTOP+RP groups ( P<0?05) , and no significant change was found in the parameters mentioned above in group BNI+RP ( P>0?05) . Conclusion RP can mitigate in?testinal I∕R injury in rats, and the mechanism is related to the anti?apoptotic effect mediated by activation ofδ?and μ?opioid receptors, but not κ?opioid receptors.

Objective To investigate the influence of electrocardiogram(ECG)-controlled dose modulation on exposure dosage and image quality of cardiac CT imaging in a cardiac phantom with simulated fluctuant heart rate.Methods The basal heart rate of the cardiac pulsating phantom was set as 60 bpm.the experimental situations were divided as 6 groups according to different heart rates.The cardiac imaging was performed on the cardiac phantom when the ECG-controlled dose modulation was firstly turned off.The exposure dosage of each scan sequence was documented.The standard deviation of the CT values of the phantom was measured on the central slice after coronal reformation of the raw data.The quality of 2D and 3D images were scored.Thell cardiac imaging was performed when ECG modulation was on and set as four groups according to different modulation parameters.All the data were documented as before.The results from the five groups with and without ECG modulation current were analyzed bv F test and comparative rank sum test using the statistical software SPSS 10.0.Results Statistical analysis showed no significant difference(P＞0.05)between the SNR of images(SD value was 27.78 and 26.30)from the groups that full mA output at wide reconstruction phase(69%～99%)when the heart rate was fluctuant(≥7.5 bpm).There was also no significant difference(P＞0.05)between the quality of the 2D and 3D images.But there was a significant difference(P＜0.01)between the SNR of images(SD value was 26.78 and 29.90)that full mA was only used at 85%reconstruction phase when the heart rate Was fluctuant(≥7.5 bpm).The exposure dosage was remarkably reduced when the ECG modulated current was on than when it Was off under fluctuant heart rate.Furthermore.there were significant difierence(P＜0.01)among the difierent ECG modulated current parameter groups.The exposure dosage can be reduced by 44.7%under the situation that the heart rate was fluctuant.Whell the fluctuation of the heart rate was≤12.5 bpm,there wag no obvious relationship between the fluctuation of the heart rate and the exposure dosage (the variation was from 0.1 to 1.1 mSv),but if the heart rate fluctuation was＞12.5 bpm,the exposure dosage would increase obviously (from 0.6 to 1.7 mSv).Conclusion For cardiac imaging with 16-slice row CT,the application of ECG modulated current can effectively reduce the exposure dosage without compromising the image quality even if heart rate was fluctuant.

Objective:To compare surgery-related indicators, patient recovery status, perioperative complications and risk factors affecting the occurrence of postoperative grade Ⅲ or higher complications in patients undergoing laparoscopic gastric mesenchymal tumor surgery with different visceral fat areas.Methods:Clinical data of 116 patients with gastric interstitial tumor in Shaanxi Provincial People′s Hospital from April 2014 to June 2020 were retrospectively analyzed, including 44 male patients and 72 female patients, with patient aged from 25 to 88 years old and the mean age was (61.8±10.7) years, including 54 patients in the high VFA group and 62 patients in the low VFA group. SPSS 23.0 was used for statistical analysis, and t-test and χ2 test were applied to compare and analyze the patients′ surgery-related indexes, postoperative recovery status, complications within 30 d after surgery and differences in Clavien-Dindo classification of complications, while univariate and multifactorial analyses were used to study the factors affecting the occurrence of postoperative grade Ⅲ or higher complications. Results:Patients in the high VFA group had a higher body mass index than in the low VFA group, and the difference was statistically significant ( t=4.48, P<0.001); patients in the high VFA group had longer operative time ( t=2.88, P=0.005), more intraoperative bleeding ( t=2.17, P=0.032), longer period of fasting ( t=2.73, P=0.008), longer time for defecation ( t=4.46, P<0.001) and bowel movement ( t=4.62, P<0.001), and longer postoperative hospital stay ( t=3.43) compared with those in the low VFA group ( t=2.73, P=0.001), prolonged defecation ( t=4.46), prolonged bowel movement ( t=4.62), and prolonged postoperative hospitalization ( t=3.43), with statistically significant differences ( P<0.05); the incidence of postoperative complications was significantly higher in the high VFA group (31.4%) compared with the low VFA group (14.5%) ( χ2=4.78, P=0.029); among them, the incidence of postoperative pulmonary infection was significantly higher in patients in the high VFA group (12.9%) compared with those in the low VFA group (1.6%), and the difference between them was statistically significant ( χ2=4.16, P<0.05); while the differences in postoperative incision-related complications, anastomotic fistula, lower limb venous thrombosis, and intestinal obstruction were not statistically significant ( P>0.05). The incidence of postoperative complications above grade Ⅲ of the Clavien-Dindo complication classification was significantly higher in patients in the high VFA group (16.7%) compared with those in the low VFA group (4.8%), and the difference between the two was statistically significant ( χ2=4.35, P<0.05); univariate analysis revealed that operative time ≥300 min and increased VFA were the risk factors for postoperative grade Ⅲ or higher complications, while VFA was not an independent risk factor. Conclusion:Larger visceral fat area increases the difficulty of laparoscopic gastric mesenchymal tumor surgery operation, and also affects patients′ postoperative recovery, leading to increased postoperative complications, but VFA is not an independent risk factor affecting the occurrence of postoperative grade Ⅲ or higher complications in patients with gastric mesenchymal tumor.