Objective:To explore the protective effect of vagus nerve stimulation (VNS) on the prognosis of rats suffering from cardiac arrest/cardiopulmonary resuscitation (CA/CPR) under different treatment timings.Methods:The method of percutaneous epicardial electrical stimulation was used to establish CA model of rat. Fifty-three male SD rats were randomly (random number) divided into the sham group ( n=5), CPR group ( n=12), PRE group ( n=12), POST5 group ( n=12) and POST30 group ( n=12). The sham group did not experience CA/CPR. VNS treatment was started at 30 min before CA (PRE group, n=12), 5 min after recovery of spontaneous circulation (ROSC) (POST5 group, n=12), and 30 min after ROSC (POST30 group, n=12) in different VNS-treated group, respectively. The electrical stimulation was applied to the vagus nerve for 30 min with a unified parameter. The neurological deficit scores at 24, 48, and 72 h after ROSC were recorded, and the survival rate in each group was observed. TUNEL staining was used to detect the apoptosis of cortical area and the expression of α7 nicotinic acetylcholine receptor (α7nAChR) in brain tissue was measured by immunofluorescence at 72 h after ROSC. Variables were compared with one-way analysis of variance, and survival for Kaplan-Meier curves were tested with the log-rank test. A P value less than 0.05 was considered statistically significant. Results:Compared with the CPR group (survival rate 33.33%), both pre-treatment (survival rate 75%) and post-treatment of VNS (POST5 group survival rate 75% and POST30 group survival rate 83.33%) significantly improved the 72 h survival rate after CPR ( P<0.05), mitigated neurological deficits after ROSC, reduced the positive rate of apoptosis neurons, and up-regulated the expression of α7nAChR in cerebral cortex. There was no significant difference among the VNS-treated groups (all P>0.05). Conclusions:Both pre-treatment and post-treatment of VNS can play a protective role in rats after CA/CPR, which may be related to the activation of α7nAChR-mediated anti-inflammatory and anti-apoptosis effects.

Objective:To investigate the application of digital teaching system in the teaching of onlay abutment teeth preparation for trainees receiving standardized residency training of stomatology (abbreviated as "resident trainees").Methods:The digital simulation teaching system unit was established by using the tissue morphology memory characteristics of 3Shape Trios oral scanner and Geomagic Control X 3D imaging design software. Eighteen resident trainees from the Daping Hospital were randomly divided into two groups, nine in the control group, preparing the onlay resin tooth model independently after taking the routine PPT + demonstration operation teaching; the other nine in the test group, preparing onlay model after learning digitization teaching system unit. All resident trainees prepared on three models respectively. After the teaching, the amounts of preparation and polymerization degree were compared between the two groups, making a summary teaching evaluation. Amounts of preparation, polymerization degree and teaching satisfaction were tested by independent-samples t-test with software SPSS 21.0. Results:Compared with the resident trainees in control group, the t values of width difference of buccal shoulder, lingual shoulder, proximal middle shoulder and distal middle shoulder, height difference of functional cusp and the lowest part of the proximal middle fossa, and degree of buccal polymerization, lingual polymerization and distal polymerization were 6.21, 6.12, 3.83, 4.73, 3.73, 4.79, 8.35, 4.35, and 6.69 respectively , while P values were respectively as <0.001, <0.001, <0.001, <0.001, 0.001, <0.001, <0.001, <0.001, and <0.001, with statistical difference ( P<0.05) . The t values of height difference of non-functional cusp, the lowest part of the distal middle fossa and degree of proximal polymerization were 1.02, 1.97, and 1.43, while P values were respectively 0.312, 0.054, and 0.158, with no statistical difference ( P>0.05). All indicators of teaching satisfaction were statistically significant ( P<0.05). Conclusions:The application of digital teaching system is conducive to improving the onlay abutment teeth preparation level of residents with high teaching satisfaction, which is worth promoting in clinical practice.

The traditional diagnosis of neuropsychiatric disorders mainly depends on the subjective evaluation of specialists,neuropsychological test,biochemical examination and other methods,which lacks objective,accurate and intelligent biomarkers.With the rapid development of neuroimaging and artificial intelligence technology,unsupervised learning has been widely used in the auxiliary diagnosis of neuropsychiatric disorders for it has the advantages of independence of external labels,high model generalization,and automatic feature extraction.Compared with the traditional supervised learning methods,unsupervised learning is more capable of achieving objective,accurate and intelligent diagnosis of neuropsychiatric disorders.Herein an overview on the applications of unsupervised learning in the auxiliary diagnosis of neuropsychiatric disorders is provided,summarizing the findings of unsupervised learning in Alzheimer's disease,schizophrenia,major depressive disorder,and autism spectrum disorder,and discussing the research challenges such as insufficient image processing capability,small sample size,insufficient biochemical index data.The corporation with neural network,multi-site large sample size,and deep fusion of multidimensional data are the development trends of unsupervised learning method.

Objective:To investigate the possible mechanism of ultrasound therapy in the rat model of sepsis.Methods:Seventy-eight male Sprague-Dawley (SD) rats were randomly divided into Sham group ( n = 12), septic model group ( n = 22), ultrasound treatment group ( n = 22), methyllycaconitine citrate (MLA) combined with ultrasound treatment group ( n = 22). In the Sham group, only the abdomen was opened, the cecum was found to be free, without cecal ligation and puncture (CLP). In the septic model group, CLP was used to replicate the septic rat model. After operation, each group of rats were subcutaneously injected with preheated 37 ℃ normal saline. The rats in the ultrasound treatment group were treated with ultrasound [Philips IU22 L9-3 ultrasound instrument and 9 MHz probe were used to break the sequence in the spleen area once every 6 seconds, with 1 second for each time, the mechanical index (MI) was 0.72, and the treatment time was 10 minutes]. In the MLA combined with ultrasound treatment group, α7 nicotinic acetylcholine receptor (α7nAChR) specific blocker MLA 4 mg/kg was injected intraperitoneally 30 minutes before operation, and ultrasound treatment was performed 2 hours after operation. The levels of tumor necrosis factor-α (TNF-α) and interleukin (IL-1β, IL-6) in serum of each group were measured by enzyme-linked immunosorbent assay (ELISA) at 24 hours after operation. The 10-day survival rate of each group was recorded, and the symptoms of each group were evaluated by clinical disease score (CDS). The histopathological changes of lung and colon were observed under light microscope. Results:Compared with the Sham group, the 10-day survival rate of rats in the septic model group was decreased significantly [40% (4/10) vs. 100% (6/6)], the CDS was (10.73±2.19 vs. 6.17±0.58) and the levels of TNF-α, IL-6, and IL-1β were increased significantly at 24 hours after operation [TNF-α (ng/L): 42.00±8.92 vs. 13.16±3.19, IL-6 (ng/L): 129.37±25.04 vs. 63.99±12.92, IL-1β(ng/L): 254.98±67.27 vs. 76.83±25.39, all P < 0.01]. Compared with the septic model group, the survival rate in the ultrasound treatment group was improved [70% (7/10) vs. 40% (4/10)], but there was no significant difference ( P > 0.05). The CDS (7.64±2.68 vs. 10.73±2.19) and the expressions of TNF-α, IL-6, and IL-1β were significantly reduced at 24 hours after operation [TNF-α(ng/L): 16.93±6.02 vs. 42.00±8.92, IL-6 (ng/L): 73.65±24.38 vs. 129.37±25.04, IL-1β(ng/L): 111.86±14.08 vs. 254.98±67.27, all P < 0.01]. Compared with the ultrasound treatment group, the survival rate in the MLA combined with ultrasound treatment group was reduced [60% (6/10) vs. 70% (7/10)], but the difference was not statistically significant ( P > 0.05). CDS was significantly increased (9.55±2.72 vs. 7.64±2.68), and the levels of TNF-α, IL-6 and IL-1β were significantly increased at 24 hours after operation [TNF-α(ng/L): 34.61±7.89 vs. 16.93±6.02, IL-6 (ng/L): 112.92±10.42 vs. 73.65±24.38, IL-1β(ng/L): 212.57±32.16 vs. 111.86±14.08, all P < 0.01]. Microscopically, in the septic model group, the alveolar septum was thickened, a large number of inflammatory cells infiltrated, normal pulmonary reticular structure disappeared, and pulmonary interstitium showed obvious hemorrhage and edema, meanwhile, the structure of colonic villi was obviously abnormal, with cells were edema and inflammatory cell infiltration, and the arrangement was disordered, so that the subepithelial space and the top of it fell off. After ultrasound treatment, the thickness of the alveolar interval in rats was similar to that in Sham group, without obvious inflammatory cell infiltration, and the pulmonary reticular structure was relatively intact. At the same time, the morphology of colonic villi was basically normal and orderly, the edema of cell was not obvious, and subcutaneous space and tip fall off were not obvious. After being antagonized by MLA, the rat lung tissue showed thickened alveolar septum, inflammatory cell infiltration, incomplete pulmonary network structure, hemorrhage and edema in the interstitium. The villi structure of the colon was faintly visible, with obvious cell edema and inflammatory cell infiltration, and the arrangement was abnormal. Conclusion:Ultrasound treatment improves the prognosis of septic rats, MLA can reverse the anti-inflammatory effect of ultrasound therapy by antagonizing α7nAChR, suggesting that the protective mechanism of ultrasound in sepsis may be related to activating the cholinergic anti-inflammatory pathway mediated by α7nAChR.