Objective To evaluate the effect of advanced age on sepsis-caused heterogeneity of nicotinic acetylcholine receptors (nAChR) in the cytomembrane of skeleton muscle in rats.Methods Twenty SPF adult rats (aged 4-5 months,weighing 250-280 g) and 20 aged male Sprague-Dawley rats (aged 18-20 months,weighing 550-600 g),were obtained from the Experimental Animal Centre of Chongqing Medical University.The adult rats were randomly divided into control group (CAd group,n =10) and sepsis group (SAd group,n =10).The aged rats were randomly divided into control group (CAg group,n =10) and sepsis group (SAg group,n =10).Sepsis was produced by cecal ligation and puncture.The specimens of anterior tibial muscle were obtained at 24 h after operation for determination of the expression of neuronal nAChR (α7-nAChR) and fetal nAChR (γ-nAChR) using immunohistochemistry and Western blot.Results The expression of γ-nAChR and α7-nAChR in the cytomembrane of anterior tibial muscle was significantly higher in CAg and SAd groups than in CAd group,and in SAg group than in CAg and SAd groups.Conclusion Advanced age can aggravate sepsis-induced heterogeneity of nAChR in the cytomembrane of skeleton muscle in rats.

We introduced the tutorial system in anesthesiology resident standardization training plan and management,and through the strict tutor qualification,strengthening tutor training mechanism,carrying out the tutor assessment mechanism and the cultivation of residents' comprehensive ability for medical treatment,scientific research and teaching,we improved the comprehensive quality of anesthesia resident physicians and the training quality.

Aim To investigate the anti-apoptotic effect of NGF on H9 c2 cardiac myocytes in a hypoxia / reox-ygenation injury model and its mechanism. Methods The H9 c2 cardiac myocytes were randomly divided into five groups:control group ( C group) , hypoxia/reoxy-genation group ( H/R group) , NGF group ( N group) , NGF+LY294002 group ( N+L group) and LY294002 group( L group) . Each group received the correspond-ing treatment. Cell survival rate was tested by cell counter kit-8 methods. Apoptotic rate was evaluated by propidium iodide ( PI ) staining and flow cytometry (FCM). The levels of Caspase-12, p-Akt/Akt were e-valuated by Western blot. Results The NGF group could significantly protect the H9 c2 cardiac myocytes under the hypoxia / reoxygenation injury with increased cell survival rate. It also decreased the apoptotic per-centage, upregulated the level of p-Akt/Akt and inhib-ited the expression of Caspase-12 . As the specific in-hibitor of PI3k receptor, LY294002 decreased the level of p-Akt. Conclusion NGF has the effect of anti-ap-optosis on H9 c2 cardiac myocytes exposed to hypoxia /reoxygenation injury via PI3k-Akt signal pathway.

Objective To evaluate the effect of electroconvulsive therapy (ECT) on the expression of phosphorylated glutamate receptor 1 (p-GluR1) and Ca2+/calmodulin-dependent protein kinase Ⅱ α (p-CaMK Ⅱ α) under small dose ketamine combined with propofol anesthesia in the depressed rats.Methods Forty healthy adult male Sprague-Dawley rats,weighing 200-250 g,aged 2-3 months,were used in this study.Mental depression was induced by exposing the animals to chronic unpredictable mild stress (CUMS).Forty mentally depressed rats were divided randomly into 5 groups (n =8 each) using a random number table:M0-4 groups.Propofol 80 mg/kg and ketamine 10 mg/kg were injected intraperitoneally in M0-4 groups.After disappearance of righting reflex,M1-4 groups received ECT of 60,120,180 and 240 mC once a day for 7 consecutive days,respectively,by means of a current (frequency 50 Hz,sine-wave,pulse width 0.7 ms,1-s duration) delivered via ear-clip electrodes,while group M0 received ECT of no quantity of electric charge via ear-clip electrodes.Before CUMS,at 1 day after CUMS and at 1 day after ECT,sucrose preference test was applied to evaluate the depressive behavior.The sucrose preference percentage (SPP) was calculated.At 4 days after CUMS and 4 days after ECT,the learning and memory function was assessed using Morris water maze test.The rats were then sacrificed,and hippocampi were isolated to detect the expression of GluR1,p-GluRl,CaMK Ⅱ α and p-CaMK Ⅱ α by Western blot.Results The SPP was significantly lower after CUMS than before CUMS in M0-4 groups (P＜0.05).Compared with that after CUMS,the SPP was significantly increased,the escape latency was shortened,and the space exploration time was prolonged after ECT in M1-4 groups (P＜0.05).There was no significant difference in SPP after ECT between M1-4 groups (P＞0.05).Compared with group M0,the SPP was significantly increased,and the expression of pGluR1 and p-CaMK Ⅱ α was up-regulated in M1-4groups (P＜0.05).Compared with group M2,the escape latency was significantly prolonged,the space exploration time was shortened,and the expression of pGluR1 and p-CaMK Ⅱ α was down-regulated after ECT in the other groups (P＜0.05).There was no significant difference in GluR1 and CaMK Ⅱ α expression after ECT between the five groups (P＞ 0.05).Conclusion ECT can induce cognitive decline when applied for anti-depression under small dose ketamine combined with propofol anesthesia,and the mechanism is related to increased phosphorylation of GluR1 and CaMK Ⅱ α expression in rats.

OBJECTIVETo study the value of clinical application and distribution character of regional pulmonary ventilation of patients with various type of pneumoconiosis.

METHODS132 patients with various type of pneumoconiosis were observed by electric impedance pneumograph(EIPV) and routine lung function test. The results were compared with the measured value of 100 healthy cases.

RESULTSThe regional pulmonary ventilation of the three kinds of pneumoconiosis(founder's pneumoconiosis, silicosis and asbestosis) was increased in both side of upper pulmonary region and decreased in both of lower pulmonary region. The ventilation distribution showed that the right pulmonary ventilation increased predominantly, accounted for 53.03% (70/132) of total lung ventilation. There was significant difference(P < 0.01) compared with the normal healthy men's EIPV, but no difference(P > 0.05) among various type of pneumoconiosis. There was also no difference(P > 0.05) between pneumoconiosis patients with normal ventilation function and various type of ventilation obstacle of pneumoconiosis. One silicosis patient complicated by atelectasis of the left upper lobe, another silicosis patient complicated by lung cancer and their EIPV accorded with their chest X-rays.

CONCLUSIONEIPV could not be measured by routine lung function test. It may be the supplement to latter parameter and as a substitute for radio imaging of pulmonary ventilation in pneumoconiosis complicated by other regional pulmonary disorder.

Objective To explore the effect of low-dose ketamine combined with propofol anesthesia on expres?sion of glutamine receptor subunit 1 (GluR1) and 2 (GluR2) in the hippocampus of depressed rats after electroconvulsive therapy. Methods Healthy adult male Sprague-Dawley rats, weighing 200~250 g, were used in this study. Mental depres?sion was induced by chronic unpredictable mild stress. Thirty-two depressed rats were randomly divided into 4 groups (n=8): metal depression group (group A), ECT group (group B), ECT+propofol group (group C) and ECT+propofol+ket?amine group (group D). Eight normal rats served as control group. Control group received no treatment. Group A received intraperitoneal injection of normal saline 8 mL/kg plus sham ECT. Group B, C and D received ECT once a day for 7 con?secutive days following intraperitoneal injection of normal saline 8 mL/kg, propofol 80 mg/kg and propofol 80 mg/kg +ketamine 10mg/kg, respectively. Sucrose preference test and Morris water maze were performed to assess depressed be?havior and learning and memory function, respectively. RT-PCR and Western-blot assay were used to detect the expres?sion of GluR1 , GluR2 and their mRNA expression. Results After ECT, compared with control group and group A, changes of SPP in group B, C and D were obvious. The change of SPP in group D was much higher than all other groups (P<0.05). Rats in group B showed prolonged escape latency and shortened space exploration time, which were significantly different from all other groups (P<0.05). Rats in group D showed the most shortened escape latency and prolonged space exploration time (P<0.05). The expression of GluR1 was significantly increased in group B, C and D compared with group A (P<0.05). The expression of GluR2 and mRNA was significantly decreased in group B and C (P<0.05). The difference in GluR2 and mRNA expression was not significant among group A, D and control group (P>0.05). Conclusion Low-dose ketamine combined with propofol anesthesia exert effective antidepressive action and improve learning and memory function of depressed rats after electroconvulsive therapy. The beneficial effects of the ketamine combined with propofol anesthesia may be related to up-regulation expression of GluR1 and GluR2 in hippocampus.

Objective To evaluate the effects of exendin-4 on glial brillary acidic protein (GFAP ) and interleukin-1β(IL-1β) expression in hippocampi of aged rats .Methods Forty-eight healthy male Sprague-Dawley rats ,aged 22-24 weeks ,weighing 500-700 g ,were randomly divided into 4 groups (n=12 each) using a random number table:control group (group C ) ,exendin-4 group (group E ) ,operation group (group O ) and exendin-4 plus operation group (group OE) .The rats were anesthetized with intraperitoneal fentanyl and droperidol .Groups C and E did not receive anesthesia or splenectomy .In O and OE groups ,splenectomy was carried out .In E and OE groups , exendin-4 5 μg/kg was injected intraperitoneally at 30 min before skin incision and 12 h after operation .C and O groups received the equal volume of normal saline instead of exendin-4 .Learning and memory function was assessed using Morris water maze test (escape latency (EL) and total swimming distance (TSD) at 1 day before operation (T0 ) .The fasting blood glucose was measured after anesthesia (T1 ) ,at the end of operation (T2 ) and on postoperative day 1 (T3 ) .The rats were sacrificed after assessment of the cognitive function at T 3 and the hippocampi were removed for determination of the expression of GFAP (by immuno-histochemistry ) and IL-1β(by Western blot ) .Results There was no significant difference in the EL and TSD at T0 between the four groups ( P>0.05) .Compared with group C ,the EL and TSD were significantly prolonged at T3 and fasting blood glucose was increased at T2 ,3 ,and the expression of IL-1βand GFAP was up-regulated at T3 in O and OE groups ( P<0.05) .Compared with group O ,the EL and TSD were significantly prolonged at T3 and fasting blood glucose was decreased at T2 ,3 ,and the expression of IL-1βand GFAP was down-regulated at T3 in group OE ( P<0.05) . Conclusion Exendin-4 can improve the postoperative cognitive function of aged rats by inhibiting inflammatory responses in hippocampi and maintaining stable perioperative blood glucose .

Objective To develop a predictive model for postoperative acute kidney injury(AKI)in elderly patients using machine learning methods.Methods The preoperative information and postopera-tive follow-up information of elderly patients who underwent surgery from June 2019 to July 2020 were col-lected,and the laboratory examination results were extracted.A total of 115 preoperative variables were in-cluded.A model of postoperative AKI was constructed using five methods:extreme gradient boosting(XGB),gradient boosting machine(GBM),random forest(RF),support vector machine(SVM),and elastic net logistic regression(ELA).The performance of the model was evaluated using area under the re-ceiver operating characteristic curve(AUROC),area under the precision recall curve(AUPRC),and Brier score.To simplify the model for clinical application,the original model was obtained and some varia-bles with low correlation were removed,and the model was evaluated again using the above method.Results This study ultimately included 5 929 elderly patients,3 359 males(56.7％)and 2 570 females(43.3％),aged 65-99 years.Among them,154 patients(2.6％)experienced postoperative AKI.Among the prediction models constructed using five machine learning methods,XGB has the highest AUROC and AU-PRC,with values of 0.798(95％CI 0.705-0.888)and 0.230(95％CI 0.079-0.374),respectively.Its Brier score is the lowest among all models,the score is 0.023(95％CI 0.014-0.029).After simplifying the XGB model,72 variables were retained.The AUROC of the simplified model was 0.790(95％CI 0.711-0.861),slightly lower than that of the original model.The AUPRC was 0.176(95％CI 0.070-0.313),and the Brier score was 0.024(95％CI 0.017-0.033),and there was no significant statistical difference,indicating that there was no significant difference in the predictive ability of the simplified model compared to the original model.Conclusion Among the five machine learning methods used to construct postoperative AKI prediction models,XGB has the best predictive performance.The simplified XGB predic-tion model still retains high predictive performance and is easier to be promoted in clinical practice.

Objective:To evaluate the relationship between preoperative pain threshold and chronic postsurgical pain (CPSP) in the patients undergoing thoracoscopic pneumonectomy.Methods:One hundred patients of both sexes, aged 18-75 yr, with body mass index of 18-35 kg/m 2, of American Society of Anesthesiologists Physical Status classification Ⅰ or Ⅱ, scheduled for thoracoscopic pneumonectomy at West China Hospital of Sichuan University from December 2019 to February 2020, were selected. The pain threshold was measured using Pain Vision at 1 day before surgery. Telephone follow-up was implemented by a pain questionnaire to assess CPSP (numerical rating scale score ≥1) at 3 months after surgery. Multivariate logistic regression was used to identify the risk factors for CPSP, and the receiver operating characteristic curve was used to evaluate the accuracy of preoperative pain threshold in predicting CPSP. Results:Ninety-four patients were finally enrolled, of which 38 cases (40%) developed CPSP. The results of multivariate logistic regression analysis showed that low preoperative pain threshold was an independent risk factor for CPSP ( OR=0.899, 95% confidence interval 0.854-0.946, P<0.001). The area under the receiver operating characteristic curve was 0.882 (95% confidence interval 0.804-0.960), Youden Index was 0.673, the sensitivity was 0.816, and the specificity was 0.857. Conclusions:Low preoperative pain threshold is an independent risk factor for CPSP, and preoperative pain threshold can predict the occurrence of CPSP in the patients undergoing thoracoscopic pneumonectomy.

Objective:To investigate the value of delta radiomics based on longitudinal changes of dynamic contrast enhanced MRI (DCE-MRI) in predicting pathological complete response (pCR) after neoadjuvant therapy (NAT) for breast cancer.Methods:The clinicopathological and imaging data of 117 patients with breast cancer confirmed by surgical pathology from April 2019 to November 2021 at Jiangxi Cancer Hospital were analyzed retrospectively. All patients were female with 23?74 (48±10) years old. The patients were randomly divided into training (81 cases) and test sets (36 cases) at the ratio of 7∶3 according to the number of random seeds in the software. All patients underwent DCE-MRI before and after early NAT (2 courses). The maximum diameter relative regression value of breast tumors before and after early NAT (D%) was calculated and used to construct a conventional imaging model. The delta radiomic features were extracted based on pre-NAT and early-NAT (2 courses) DCE-MRI and selected by redundancy analysis and least absolute shrinkage and selection operator algorithm. A ten-fold cross-validation method was used to construct the delta radiomic model and Radscore was calculated for each patient. All patients were classified into pCR group and non-pCR group according to the surgical pathology after NAT. Significant clinicopathological variables were selected by univariate analysis and stepwise regression method. They were integrated with D% and Radscore to build the combined model and nomogram. The model performance in predicting pCR after NAT in breast cancer was evaluated by the receiver operating characteristic curve and the area under the curve (AUC), and the clinical utility of the models was compared by using clinical decision curves.Results:The combined model had the best diagnostic performance among the three models, with an AUC of 0.90 in the training set and 0.87 in the test set. The Radscore had the highest weight in the nomogram. In the training set, the diagnostic performance of the combined model and delta radiomics model were better than that of the conventional imaging model ( Z=?3.48, P=0.001; Z=2.54, P=0.011). The clinical decision curves showed an overall greater clinical benefit of the combined model compared with the conventional imaging model and delta radiomic model. Conclusions:The addition of significant clinicopathological variables and Radscore of delta radiomic model which represents the longitudinal changes in tumor heterogeneity to the conventional imaging model may improve the predictive ability of pCR. The delta radiomic may serve as a noninvasive biomarker for early prediction of NAT response.