Objective:To evaluate the effect of short-chain fatty acid(SCFA) on perioperative cognitive dysfunction in aged rats through mitogen-activated protein kinase p38(p38 MAPK)/nuclear factor-κB p65(NF-κB p65) pathway.Methods:According to random number table method, 32 healthy SPF-grade male SD rats, aged 16 months and weighing 520~620 g, were divided into control group, short-chain fatty acid group (SCFA group), perioperative cognitive dysfunction group (PCD group) and perioperative cognitive dysfunction+ short-chain fatty acid group (SCFA+ PCD group), with 8 rats in each group. The perioperative cognitive dysfunction model was established by sevoflurane anesthesia plus internal fixation of tibial fractures. Rats in SCFA group and SCFA+ PCD group freely drank water added with SCFA for 28 days. On the 29th day, rats in SCFA+ FCD group underwent tibial fracture internal fixation surgery. Morris water maze test was performed on the 7th day after surgery to evaluate the cognitive function of rats. The Nissl bodies of hippocampus were observed by Nissl's staining. The hippocampus tissue was collected to analyze the expressions of interleukin-1β (IL-1β), interleukin-6 (IL-6), p38 MAPK, phosphorylated p38 MAPK, NF-κB p65 and phosphorylated NF-κB p65 by Western blot.The SPSS 27.0 software was used for statistical analysis. One-way ANOVA was used for comparison among multiple groups, and LSD- t test was used for further pairwise comparison. Results:(1) The results of Morris water maze test showed that the times of crossing the original platform, the escape latency and the residence time in the original platform quadrant were statistically significant among the four groups on the 7th day after surgery ( F=13.80, 47.80, 6.46, all P<0.05). The escape latencies of the SCFA+ PCD group and PCD group were both longer than that in the control group (both P<0.05). The times of crossing the original platform in SCFA+ PCD group and PCD group were less than that of control group (both P<0.05). The residence time in the original platform quadrant in SCFA+ PCD group and PCD group was shorter than that of control group (both P<0.05).Compared with PCD group, the escape latency was shorter, the times of crossing the original platform were more and the residence time in the original platform quadrant was longer in SCFA+ PCD group (all P<0.05). (2) The expression levels of IL-1β, IL-6, phosphorylated p38 MAPK and phosphorylated NF-κB p65 were statistically significant among the four groups ( F=184.28, 139.27, 19.40, 58.47, all P<0.05). The expression levels of IL-1β, IL-6, phosphorylated p38 MAPK and phosphorylated NF-κB p65 were higher in SCFA+ PCD group (0.49±0.10, 0.60±0.05, 0.489±0.012, 0.435±0.005) and PCD group (0.85±0.05, 1.12±0.08, 0.519±0.028, 0.473±0.008) than those in control group (0.13±0.02, 0.42±0.10, 0.437±0.010, 0.362±0.013)(all P<0.05). The expression levels of IL-1β, IL-6, phosphorylated p38 MAPK and phosphorylated NF-κB p65 were lower in SCFA+ PCD group than PCD group (all P<0.05). (3) The average gray value of Nissl bodies was statistically significant different among the four groups ( F=14.65, P<0.05). The average gray value of Nissl bodies was lower in SCFA+ PCD group (193.2±8.1) and PCD group (160.5±14.1) than that of control group (221.2±14.8) (both P<0.05). The average gray value of Nissl bodies was higher in SCFA+ PCD group than that in PCD group( P<0.05). Conclusion:Short-chain fatty acid attenuates cognitive dysfunction, which may be related with inhibiting p38 MAPK/NF-κB p65 pathway and reducing the neuroinflammation.

Objective:To evaluate the role of meningeal γδ T cell-derived interleukin-17A (IL-17A) in postoperative cognitive dysfunction (POCD) in aged mice.Methods:Forty healthy male C57BL/6N mice, aged 18 months, weighing 30-40 g, were divided into 4 groups ( n=10 each) using a table of random numbers: control group (group C), anti-γδ T cell receptor antibody (Anti-TCR γδ) group, POCD group (group P), and POCD+ Anti-TCR γδ group (group P+ Anti-TCR γδ). Anesthesia was induced with 8% sevoflurane and maintained with 3% sevoflurane, and the internal fixation for tibial fracture was performed to establish the mouse model of POCD in P and P+ Anti-TCR γδ groups. Anti-TCR γδ antibody 2.5 μg was infused into the occipital cistern on postoperative day 4 in P+ Anti-TCR γδ and Anti-TCR γδ groups. The open field test, novel object recognition test and Y-maze test were conducted sequentially at 7th day after surgery. The total distance traveled in the open field and the number of entries into the central area were recorded, and the novel object recognition index and preference index for exploring the novel arm were calculated. The mice were sacrificed at the end of the behavioral testing, the meninges were obtained for detection of the expression of IL-17A in γδ T cells by flow cytometry, and the hippocampal tissues were harvested for determination of the expression of vesicular glutamate transporter1 (VGLUT1), glutamate receptor 1 (GluR1), and IL-17A receptor (IL-17AR) (by Western blot). Results:There was no statistically significant difference in the total distance traveled in the open field test or the number of entries into the central area among the four groups ( P>0.05). Compared with group C, the novel object recognition index and preference index for novel arm exploration were significantly decreased, the expression of meningeal γδ T cells and IL-17AR in hippocampal tissues was up-regulated, and the expression of VGLUT1 and GluR1 was down-regulated in group P and group P+ Anti-TCR γδ ( P<0.05), and no significant change was found in the aforementioned parameters in group Anti-TCR γδ ( P>0.05). Compared with group P, the novel object recognition index and preference index for novel arm exploration were significantly increased, the expression of meningeal γδ T cells and IL-17AR was down-regulated, and the expression of VGLUT1 and GluR1 was up-regulated in group P+ Anti-TCR γδ ( P<0.05). Conclusions:Increased meningeal γδ T cell-derived IL-17A can up-regulate the expression of IL17AR in the hippocampus and down-regulate the expression of VGLUT1 and GluR1, thus involving in the development of POCD in aged mice.

Objective:To evaluate the effect of short-chain fatty acid(SCFA) on perioperative cognitive dysfunction in aged rats through mitogen-activated protein kinase p38(p38 MAPK)/nuclear factor-κB p65(NF-κB p65) pathway.Methods:According to random number table method, 32 healthy SPF-grade male SD rats, aged 16 months and weighing 520~620 g, were divided into control group, short-chain fatty acid group (SCFA group), perioperative cognitive dysfunction group (PCD group) and perioperative cognitive dysfunction+ short-chain fatty acid group (SCFA+ PCD group), with 8 rats in each group. The perioperative cognitive dysfunction model was established by sevoflurane anesthesia plus internal fixation of tibial fractures. Rats in SCFA group and SCFA+ PCD group freely drank water added with SCFA for 28 days. On the 29th day, rats in SCFA+ FCD group underwent tibial fracture internal fixation surgery. Morris water maze test was performed on the 7th day after surgery to evaluate the cognitive function of rats. The Nissl bodies of hippocampus were observed by Nissl's staining. The hippocampus tissue was collected to analyze the expressions of interleukin-1β (IL-1β), interleukin-6 (IL-6), p38 MAPK, phosphorylated p38 MAPK, NF-κB p65 and phosphorylated NF-κB p65 by Western blot.The SPSS 27.0 software was used for statistical analysis. One-way ANOVA was used for comparison among multiple groups, and LSD- t test was used for further pairwise comparison. Results:(1) The results of Morris water maze test showed that the times of crossing the original platform, the escape latency and the residence time in the original platform quadrant were statistically significant among the four groups on the 7th day after surgery ( F=13.80, 47.80, 6.46, all P<0.05). The escape latencies of the SCFA+ PCD group and PCD group were both longer than that in the control group (both P<0.05). The times of crossing the original platform in SCFA+ PCD group and PCD group were less than that of control group (both P<0.05). The residence time in the original platform quadrant in SCFA+ PCD group and PCD group was shorter than that of control group (both P<0.05).Compared with PCD group, the escape latency was shorter, the times of crossing the original platform were more and the residence time in the original platform quadrant was longer in SCFA+ PCD group (all P<0.05). (2) The expression levels of IL-1β, IL-6, phosphorylated p38 MAPK and phosphorylated NF-κB p65 were statistically significant among the four groups ( F=184.28, 139.27, 19.40, 58.47, all P<0.05). The expression levels of IL-1β, IL-6, phosphorylated p38 MAPK and phosphorylated NF-κB p65 were higher in SCFA+ PCD group (0.49±0.10, 0.60±0.05, 0.489±0.012, 0.435±0.005) and PCD group (0.85±0.05, 1.12±0.08, 0.519±0.028, 0.473±0.008) than those in control group (0.13±0.02, 0.42±0.10, 0.437±0.010, 0.362±0.013)(all P<0.05). The expression levels of IL-1β, IL-6, phosphorylated p38 MAPK and phosphorylated NF-κB p65 were lower in SCFA+ PCD group than PCD group (all P<0.05). (3) The average gray value of Nissl bodies was statistically significant different among the four groups ( F=14.65, P<0.05). The average gray value of Nissl bodies was lower in SCFA+ PCD group (193.2±8.1) and PCD group (160.5±14.1) than that of control group (221.2±14.8) (both P<0.05). The average gray value of Nissl bodies was higher in SCFA+ PCD group than that in PCD group( P<0.05). Conclusion:Short-chain fatty acid attenuates cognitive dysfunction, which may be related with inhibiting p38 MAPK/NF-κB p65 pathway and reducing the neuroinflammation.

Objective:To evaluate the role of meningeal γδ T cell-derived interleukin-17A (IL-17A) in postoperative cognitive dysfunction (POCD) in aged mice.Methods:Forty healthy male C57BL/6N mice, aged 18 months, weighing 30-40 g, were divided into 4 groups ( n=10 each) using a table of random numbers: control group (group C), anti-γδ T cell receptor antibody (Anti-TCR γδ) group, POCD group (group P), and POCD+ Anti-TCR γδ group (group P+ Anti-TCR γδ). Anesthesia was induced with 8% sevoflurane and maintained with 3% sevoflurane, and the internal fixation for tibial fracture was performed to establish the mouse model of POCD in P and P+ Anti-TCR γδ groups. Anti-TCR γδ antibody 2.5 μg was infused into the occipital cistern on postoperative day 4 in P+ Anti-TCR γδ and Anti-TCR γδ groups. The open field test, novel object recognition test and Y-maze test were conducted sequentially at 7th day after surgery. The total distance traveled in the open field and the number of entries into the central area were recorded, and the novel object recognition index and preference index for exploring the novel arm were calculated. The mice were sacrificed at the end of the behavioral testing, the meninges were obtained for detection of the expression of IL-17A in γδ T cells by flow cytometry, and the hippocampal tissues were harvested for determination of the expression of vesicular glutamate transporter1 (VGLUT1), glutamate receptor 1 (GluR1), and IL-17A receptor (IL-17AR) (by Western blot). Results:There was no statistically significant difference in the total distance traveled in the open field test or the number of entries into the central area among the four groups ( P>0.05). Compared with group C, the novel object recognition index and preference index for novel arm exploration were significantly decreased, the expression of meningeal γδ T cells and IL-17AR in hippocampal tissues was up-regulated, and the expression of VGLUT1 and GluR1 was down-regulated in group P and group P+ Anti-TCR γδ ( P<0.05), and no significant change was found in the aforementioned parameters in group Anti-TCR γδ ( P>0.05). Compared with group P, the novel object recognition index and preference index for novel arm exploration were significantly increased, the expression of meningeal γδ T cells and IL-17AR was down-regulated, and the expression of VGLUT1 and GluR1 was up-regulated in group P+ Anti-TCR γδ ( P<0.05). Conclusions:Increased meningeal γδ T cell-derived IL-17A can up-regulate the expression of IL17AR in the hippocampus and down-regulate the expression of VGLUT1 and GluR1, thus involving in the development of POCD in aged mice.

Objective:To evaluate the effect of transcutaneous auricular vagus nerve stimulation (taVNS) on tourniquet-induced hypertension (TIH) in the patients undergoing anterior cruciate ligament reconstruction.Methods:Seventy-four patients of either sex, aged 18-60 yr, of American Society of Anesthesiologists Physical Status classification I or II, with body mass index of 18-30 kg/m 2, undergoing elective anterior cruciate ligament reconstruction under general anesthesia combined with preoperative femoral nerve block, were divided into 2 groups ( n=37 each) using a random number table method: sham stimulation group (group SS) and group taVNS. Group SS received stimulation on the ear lobe and the tail of the helix of the left ear. Group taVNS received stimulation on the cymba concha and the earlobe of the left ear. Both groups received stimulation from 1 h before induction of anesthesia until the end of the procedure (frequency of 30 Hz, pulse width of 300 μs, and amplitude of the strongest current that could be tolerated by the patient in the absence of pain). The tourniquet inflation pressure was 280 mmHg, with an inflation time of 60-90 min. Systolic blood pressure, diastolic blood pressure and heart rate were recorded before tourniquet inflation to assess the development of intraoperative TIH. The consumption of intraoperative propofol, remifentanil, nitroglycerin, esmolol, norepinephrine and atropine was recorded, and the occurrence of postoperative nausea and vomiting, skin itching and headache and dizziness was also recorded. Results:Compared with group SS, the incidence of TIH and the number of patients used nitroglycerin were significantly reduced ( P<0.05), and no significant changes were found in the other parameters in group taVNS ( P>0.05). Conclusions:taVNS can decrease the occurrence of TIH in the patients undergoing anterior cruciate ligament reconstruction.

Objective:To evaluate the effect of short-chain fatty acids on microglial synapse engulfment in aged rats with postoperative cognitive dysfunction (POCD).Methods:Forty-eight healthy male Sprague-Dawley rats, aged 18 months, weighing 520-650 g, were divided into 4 groups ( n=12 each) using a random number table method: control group (group C), short-chain fatty acids group (group S), POCD group (group P), and POCD+ short-chain fatty acids group (group PS). Rats received short-chain fatty acids (sodium propionate 25.9 mmol/L, sodium butyrate 40 mmol/L and sodium acetate 67.5 mmol/L) in the free drinking water for 28 days in S and PS groups. On day 29, anesthesia was induced with 4%-5% sevoflurane and maintained with 3% sevoflurane, and the tibial fracture internal fixation was performed to prepare a rat model of POCD in P group and PS group. Morris water maze test was performed at day 7 after surgery. The escape latency, times of crossing the original platform, mean swimming speed and time spent in the original platform quadrant were recorded. The rats were sacrificed at the end of Morris water maze test, and the brains were collected to analyze the number and density of dendritic spines in the hippocampal CA1 region (by Golgi staining) and to determine the expression of postsynaptic density 95 (PSD95) and complement 1q (C1q) in the hippocampal CA1 region (by immunofluorescence). Results:Compared with group C, the times of crossing the original platform were significantly decreased, the time spent in the original platform quadrant was shortened, the escape latency was prolonged, the number and density of dendritic spines and the number of intersection points between dendrites and concentric circles were decreased, the expression of PSD95 was down-regulated, and the expression of C1q was up-regulated in P and PS groups ( P<0.05). Compared with group P, the times of crossing the original platform were significantly increased, the time spent in the original platform quadrant was prolonged, the escape latency was shortened, the number and density of dendritic spines and the number of intersection points between dendrites and concentric circles were increased, the expression of PSD-95 was up-regulated, and the expression of C1q was down-regulated in group PS ( P<0.05). Conclusions:The mechanism by which short-chain fatty acids attenuates POCD is related to decreased microglial engulfment of synapses in aged rats.

Objective:Based on the Delphi method, the electronic intelligent kanban system for general ward nursing was constructed, and its clinical application was studied.Methods:This study was the quasi experimental research, 39 nursing staff working in the experimental ward of electronic intelligent kanban in general surgery of Zhongshan Hospital Fudan University in November 2021 and November 2022 were selected, Delphi expert consultation was used to develop the menus and detailed contents of general ward nursing electronic intelligent kanban system, and it was used in clinical practice. We used the Chinese version of the Nursing Assessment of Shift Report to evaluate the effect of nursing staff before and after the application.Results:The authority coefficients of the two rounds of expert consultation were 0.868 and 0.886 respectively, and the Kendall coordination coefficients of expert consultation were 0.068 and 0.076 respectively (all P<0.01). Finally, the electronic intelligent kanban consisted of 4 first-level menus, 8 second-level menus and 13 third-level menus. After the application of electronic intelligent kanban, the score of Nursing Assessment of Shift Report increased from (79.62 ± 7.64) to (83.51 ± 2.47), with a statistically significant difference ( t=-3.03, P<0.05). Conclusions:The constructed nursing electronic intelligent kanban system was scientific and reliable, which will be beneficial to improve the the effect of nurse shift handover.

Objective:To evaluate the effect of pre-injection of young rat plasma on cognitive dysfunction after cerebral ischemia-reperfusion (I/R) in aged rats and the role of phosphatidylinositol 3-kinase/serine threonine protein kinase (PI3K/Akt) signaling pathway.Methods:Seventy-two SPF-grade healthy male Sprague-Dawley rats, aged 18 months, weighing 600-650 g, were divided into 4 groups ( n=18 each) by the random number table method: control group (group C), cerebral I/R group (group IR), pre-injection of young rat plasma group (group P) and PI3K inhibitor LY294002 group (group LY). In group P and group LY, young rat plasma 100 μl/time was injected via the tail vein. In group C and group IR, the equal volume of normal saline was injected via the the tail vein, 2 times a week for 4 weeks. Then the model of cerebral I/R injury was developed under sevoflurane anesthesia in IR, P and LY groups. LY294002 0.3 mg/kg was injected through the tail vein at 1 h before anesthesia in LY group. The neurological deficit score (Longa score) was performed at 24 h after reperfusion, and then 6 rats were randomly sacrificed, and brain tissues were obtained to determine the cerebral infarct volume. Spontaneous mobility and anxiety-like behavior were assessed by the open field test at day 29 of reperfusion, and cognitive function was assessed by the novel object recognition test at day 30 of reperfusion. At the end of the behavioral test, rats were sacrificed, hippocampal tissues were isolated for determination of the expression of phosphorylated PI3K (p-PI3K), phosphorylated Akt (p-Akt), postsynaptic dense protein-95 (PSD-95) and synaptic vesicle protein (SYN) (by Western blot), and the dendritic length and dendritic spine density of neurons in the hippocampal CA1 region. Results:There was no significant difference in motor speed, distance traveled, and time of staying at the center of the open field among the four groups ( P>0.05). Compared with group C, the Longa score and cerebral infarct volume were significantly increased, the percentage of novel object exploration and discrimination index were decreased, the expression of p-PI3K, p-Akt, PSD-95 and SYN in hippocampal tissues was down-regulated, and the dendritic length and dendritic spine density of hippocampal neurons were decreased in IR, P and LY groups ( P<0.05). Compared with group IR, Longa score and cerebral infarct volume were significantly decreased, the percentage of novel object exploration and discrimination index were increased, the expression of p-PI3K, p-Akt, PSD-95 and SYN in hippocampal tissues was up-regulated, and the dendritic length and dendritic spine density of hippocampal neurons were increased in group P ( P<0.05), and no significant change was found in the parameters mentioned above in group LY ( P>0.05). Compared with group P, Longa score and cerebral infarct volume were significantly increased, the percentage of novel object exploration and discrimination index were decreased, the expression of p-PI3K, p-Akt, PSD-95 and SYN in hippocampal tissues was down-regulated, and the dendritic length and dendritic spine density of hippocampal neurons were decreased in group LY ( P<0.05). Conclusions:Pre-injection of young rat plasma can attenuate cognitive dysfunction after cerebral I/R in aged rats, and the mechanism is related to activation of hippocampal PI3K/Akt signaling pathway and improvement in synaptic plasticity.

Objective:To evaluate the effect of esketamine on hippocampal neuronal necroptosis in aged rats with postoperative cognitive dysfunction.Methods:One hundred and twenty SPF-grade healthy male Sprague-Dawley rats, aged 22 months, weighing 550-600 g, were divided into 4 groups ( n=30 each) using a random number table method: control group (group C), postoperative cognitive dysfunction group (group P), postoperative cognitive dysfunction+ esketamine group (group PE), and esketamine group (group CE). Rats received exploratory laparotomy under sevoflurane anesthesia, and esketamine 10 mg/kg and the equal volume of 0.9% sodium chloride were intraperitoneally injected at the end of surgery once a day for 6 consecutive days in group P and group PE, respectively. Rats received no anesthesia and surgery, and esketamine 10 mg/kg and the equal volume of 0.9% sodium chloride were intraperitoneally injected at the end of surgery once a day for 6 consecutive days in group CE and group C, respectively. Morris water maze test was performed at 7th day after surgery. The escape latency, times of crossing the original platform and time spent in the original platform quadrant were recorded. The rats were sacrificed at the end of Morris water maze test, and the hippocampal tissues were collected for determination of the rate of necroptosis and cytosolic Ca 2+ concentrations (by flow cytometry) and expression of mixed lineage kinase domain-like protein (MLKL), phosphorylated MLKL (p-MLKL), receptor-interacting protein kinase-3 (RIPK3), phosphorylated RIPK3 (p-RIPK3), receptor-interacting protein kinase-1 (RIPK1) and phosphorylated RIPK1 (p-RIPK1) (by Western blot). Results:Compared with group C, the escape latency was significantly prolonged, the times of crossing the original platform were decreased, the time spent in the original platform quadrant was shortened, the necroptosis rate of hippocampal neurons and cytosolic Ca 2+ concentrations were increased, and the expression of MLKL, p-MLKL, RIPK3, p-RIPK3, RIPK1 and p-RIPK1 was up-regulated in group P and group PE ( P<0.05). Compared with group P, the escape latency was significantly shortened, the times of crossing the original platform were increased, the time spent in the original platform quadrant was prolonged, the necroptosis rate of hippocampal neurons and cytosolic Ca 2+ concentrations were decreased, and the expression of MLKL, p-MLKL, RIPK3, p-RIPK3, RIPK1 and p-RIPK1 was down-regulated in group PE ( P<0.05). Conclusions:The mechanism by which esketamine attenuates postoperative cognitive dysfunction may be related to inhibition of necroptosis in hippocampal neurons of aged rats.

Objective:To evaluate the role of brain-derived neurotrophic factor (BDNF)/tropomyosin-related kinase B (TrkB) signaling pathway in pre-injection of young rat plasma-induced reduction of sevoflurane-caused cognitive dysfunction in aged rats.Methods:Eighty SPF healthy male Sprague-Dawley rats, aged 18 months, weighing 550-650 g, were divided into 4 groups ( n=20 each) using a random number table method: control group (group C), sevoflurane anesthesia group (group S), young rat plasma group (group Y) and BDNF/TrkB signaling pathway inhibitor K252a group (group K). The plasma 100 μl obtained from 3-month-old young rats was injected via the tail vein in group Y and group K, while the equal volume of normal saline was given via the tail vein in group C and group S, twice a week, for 4 weeks.In S, Y and K groups, 3% sevoflurane was inhaled for 3 h starting from the end of treatment, and BDNF/TrkB signaling pathway inhibitor K252a was injected via the tail vein before anesthesia in group K. The open field test and Morris water maze test were performed at 3 days after anesthesia to assess the spontaneous motor ability and cognitive function.Then the rats were sacrificed, and the hippocampal tissues were isolated for determination of the expression of BDNF, phosphorylated TrkB (p-TrkB), postsynaptic dense protein-95 (PSD-95) and synaptic vesicle protein (SYN) (by Western blot), dendritic length and dendritic ridge density of neurons in hippocampal CA1 area (by Golgi staining), and the number of synapses and length of synaptic active area (with a transmission electron microscope). Results:Compared with group C, the escape latency was significantly prolonged, the number of crossing the original platform was reduced, the expression of p-TrkB, BDNF, PSD-95 and SYN was down-regulated, and the dendritic length, dendritic ridge density, the number of synapses and length of synaptic active area were decreased in group S ( P<0.05). Compared with group S, the escape latency was significantly shortened, the number of crossing the original platform was increased, the expression of p-TrkB, BDNF, PSD-95 and SYN was up-regulated, and the dendritic length, dendritic ridge density, the number of synapses and length of synaptic active area were increased in group Y ( P<0.05). Compared with group Y, the escape latency was significantly prolonged, the number of crossing the original platform was reduced, the expression of p-TrkB, BDNF, PSD-95 and SYN was down-regulated, and the dendritic length, dendritic ridge density, the number of synapses and length of synaptic active area were decreased in group K ( P<0.05). Conclusions:The mechanism by which pre-injection of young rat plasma reduces sevoflurane-induced cognitive dysfunction is related to activation of BDNF/TrkB signaling pathway and improvement in synaptic plasticity in the hippocampus of aged rats.