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Objective:To make a new simple respirator and observe the oxygen therapy effect of the respirator on patients with severe and critical coronavirus disease 2019 (COVID-19).Methods:Based on the infectivity and hospital requirements of COVID-19, a new simple respirator was designed by the medical staff of the Department of Anesthesiology of the Second Affiliated Hospital of Nanchang University, which was applied on the 22 patients with severe and critical COVID-19 who needed oxygen therapy admitted to the Cancer Center of Tongji Medical College of Huazhong University of Science and Technology from February 15th to March 15th in 2020. The new simple respirator contained two National Utility Model Patents (a respirator: ZL 2015 2 0410623.6, a fluid switch and oxygen suction device: ZL 2017 2 0873509.6), which was mainly composed of anesthesia mask and filter, L-shaped connecting tube, soft breathing bladder, connecting tube and elastic fixing belt. When in use, the anesthesia mask was fixed to the patient's mouth and nose with elastic straps, the connecting tube was inserted into the oxygen meter interface, the oxygen flow was adjusted to 6-10 L/min, and the L-shaped connecting tube was opened immediately after the soft breathing bag was full. The carbon dioxide and excess oxygen in the body was discharged from exhaust port. The oxygen flow was lowered to 2-3 L/min, the patient's respiratory rate (RR) was observed through the soft breathing bag fluctuations, and the oxygen flow was adjusted at any time. The changes of pulse oxygen saturation (SpO 2), RR and heart rate (HR) before and after application of new simple respirator were observed, and the blood gas test results of part of the patients were collected. Results:Twenty-two patients with severe and critical COVID-19 had significantly higher SpO 2 at 10 minutes after application of the new simple ventilator than before application (0.994±0.007 vs. 0.952±0.017, P < 0.01), and RR was significantly lower than that before application (times/min: 27.59±3.63 vs. 29.64±3.81, P < 0.01); after 1 day of application, each index was further improved. All 13 patients who received blood gas analysis indicated no carbon dioxide accumulation. Conclusions:The new simple respirator can significantly improve the oxygen therapy effect of patients with severe and critical COVID-19. At the same time, 2019 novel coronavirus (2019-nCoV) can be filtered through the filter to reduce the formation of aerosol and protect the medical staff and patients.
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Objective To evaluate the effect of preoperative sleep deprivation on hippocampal Tolllike receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway in aged mice with postoperative cognitive dysfunction.Methods Sixty clean-grade healthy male C57BL/6J mice,aged 16 months,weighing 28-36 g,were divided into 4 groups (n=15 each) using a random number table method:control group (group C),surgery group (group S),sleep deprivation group (group SD) and sleep deprivation plus surgery group (group SD+S).Mice were fed a common diet in group C.Mice were sleep-deprived for 24 h in group SD.Tibial fracture internal fixation was performed in group S.Tibial fracture internal fixation was performed after 24-h sleep deprivation in group SD+S.Cognitive function was assessed using the contextual fear conditioning test at days 3 and 7 after operation.The animals were sacrificed at day 7 after operation,brains were removed and hippocampi were isolated for determination of tumor necrosis factor-alpha (TNF-α) content (by enzyme-linked immunosorbent assay) and expression of TLR4 and p-NF-κB p65 (by Western blot).Results Compared with group C,the percentage of time spent freezing induced by condition and percentage of time spent freezing induced by context were significantly decreased at days 3 and 7 after operation,the content of TNF-α was increased,and the expression of TLR4 and p-NF-κB p65 was up-regulated in S,SD and SD+S groups (P<0.05).Compared with group S and group SD,the percentage of time spent freezing induced by condition and percentage of time spent freezing induced by context were significantly decreased at days 3 and 7 after operation,the content of TNF-α was increased,and the expression of TLR4 and p-NF-κB p65 was up-regulated in group SD+S (P<0.05).Conclusion Preoperative sleep deprivation further accentuates postoperative cognitive dysfunction,and the mechanism is related to activating TLR4/NF-κB signaling pathway and inducing inflammatory responses of aged mice.
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BACKGROUND:Hydroxyapatite (HA) is a good scaffold material, and recombinant human bone morphogenetic protein-2 (rhBMP-2) possesses a strong osteogenic ability, therefore, by which preparing a novel composite material wil be helpful for bone repair. OBJECTIVE:To explore the effects of the hol ow HA/rhBMP-2 microspheres on the osteogenesis and biomechanics of rabbit bone defects. METHODS:Forty-eight male healthy adult New Zealand white rabbits were randomly divided into three groups (n=16 per group), including composite, single and control groups. Radical defect models were prepared, and the hol ow HA/rhBMP-2 and hol ow HA scaffolds were implanted into the composite and single groups, respectively. The control group received no treatment. At the 1st day of 4, 8, 12, and 16 weeks after implantation, the level of serum alkaline phosphatase was detected, and the bone healing was assessed through X-ray, three-dimensional CT, radionuclide bone scan and biomechanics testing, respectively. RESULTS AND CONCLUSION:The level of serum alkaline phosphatase, X-ray scale scores, osteogetic effect, region of interest volume, three-dimensional CT and biomechanical strength in the composite group were superior to those in the single group. In the meanwhile, the bone healing was unsatisfactory in the control group. Our findings indicate that the hol ow HA/rhBMP-2 artificial bone exhibits a good osteogenic ability and mechanical strength, contributing to bone healing.
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Objective To compare the effectiveness of postoperative analgesia and early rehabil-itation between the wound infiltration combined with intravenous analgesia and epidural analgesia after hepatectomy.Methods Forty-eight patients with liver carcinoma,37 males and 1 1 females,aged 40-65 years,ASA physical status Ⅰ or Ⅱ,were randomly divided into two groups.Patients in group T were given 0.375% ropivacaine 30 ml for incision infiltration before closing the abdomen and intrave-nous analgesia.Patients in group E were given 0.2% ropivacaine 100 ml for epidural analgesia. Pareoxib sodium 40 mg was injected intravenously 30 min toward the end of the operation.Pain scores were assessed by VAS at postoperative 2,6,12,24 and 48 h.Postoperative activity distance was re-corded on 1st,2nd,3th day after surgery;the time first getting off bed and hospital stay were recor-ded.Finally,the complications were also recorded.Results Compared with group T,VAS scores at rest and in activity 12,24 and 48 h postoperatively were significantly lower (P <0.05 ).Compared with group E,postoperative activity distance on 1st,2nd and 3th day after surgery in group T were shorter.Furthermore,the time first getting off bed and the hospital stay in group T were shorter than those in group E (P <0.05).The incidence of adverse reactions between the two groups had no sta-tistical significance.Conclusion The wound infiltration combined with intravenous analgesia is benefi-cial to early recovery and shorter hospital stay.
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Objective To evaluate the role of p38 MAPK signal transduction pathway in dexmedetomidine against neurotoxicity induced by bupivacaine.Methods Seventy-two adult male SD rats,successfully implanted with intrathecal catheter without complications,were randomly divided into 6 groups: control group (group C);p38MAPK inhibitor group(group SB);dexmedetomidine group (group D);bupivacaine group (group B);dexmedetomidine and bupivacaine group (group DB);p38MAPK inhibitor and bupivacaine group (group SBB).DMSO 20 μl were injected intrathecally in group C;p38MAPK inhibitor 30 μg and 5% bupivacaine were respectively injected intrathecally in group SB and B;group DB and SBB were respectivel pretreated with dexmedetomidine 75 μg/kg intraperitoneally and p38MAPK inhibitor 30 μg intrathecal injection 20 min before intrathecally injected 5% bupivacaine.Dexmedetomidine 75 μg/kg was injected intraperitoneally in group D.Mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were measured before intrathecal catheter was implanted (T0),before intrathecal administration (T1) and at 4,8 and 12 h and on 1,2,3,4,5 and 6 days after intrathecal administration (T2-T10).At 24 h after intrathecal administration,6 rats were randomly chosen from each group and sacrificed.The lumbar segment (L4-5) of the spinal cord was removed for detecting neuronal apoptosis (by TUNEL) and phosporylated p38MAPK(p-p38MAPK) expression (by Western blot).Results Compared with T0,MWT was significantly increased and TWL was prolonged at T2-T9 in group B,MWT at T2-T7 was significantly increased and TWL at T2-T6 was prolonged in group DB,MWT was significantly increased and TWL was prolonged at T2-T5 in group SBB (P<0.05).Compared with group C,no significant difference was found in MWT,TWL,the apoptotic index and expression of p-p38MAPK in groups D and SB.MWT was significantly increased and TWL was prolonged at T2-T9 in group B,the apoptotic index and expression of p-p38MAPK were significantly increased in group B (P<0.05).Compared with group B,MWT and TWL at T2-T9,the apoptotic index and expression of p-p38MAPK were significantly decreased in groups DB and SBB (P<0.05).Conclusion Dexmedetomidine can inhibit spinal neurotoxicity induced by bupivacaine in rats via inhibiting apoptosis in spinal cord,and inhibition of p38 MAPK signal transduction pathway may be involved in the underlying mechanism.
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Objective To investigate the effects of ulinastatin with parecoxib sodium on early cellular immunology function and cognitive function in elderly patients undergoing total hip replacement.Methods One hundred patients (aged 65-80 years,ASA grade Ⅱ) undergoing elective total hip replacement were randomly assigned into 4 groups: group W(n=25),group P(n=25),group WP(n=25) and group C(n=25).The patients in group W received intravenous injection of ulinastatin with a dose of 5 000 U/kg before skin incision and at the moment of the end of operation.Patients in group P accepted intravenous injection of parecoxib sodium of 40 mg before anesthesia and at a 12 h intervals for six times.Patients in group WP accepted intravenous injection of ulinastatin with a dose of 5 000 U/kg before skin incision and at the moment of the end of operation,and accepted intravenous injection of parecoxib sodium with a dose of 40 mg before anesthesia and at a 12 h interval for six times.Patients in group C were given normal saline at the same time as placebo.The operation time,the volume of bleeding and autologous blood receiving and the intraoperative fentanyl consumption were recorded in four groups.Blood samples were obtained before induction (T0),at the end of operation (T1),on 6 h (T2),24 h (T3),72 h (T4) after operation for determination of plasma concentration of S100β protein,neuron-specific enolase(NSE),IL-6,TNF-α.The percentages of T lymphocyte subsets (CD3+,CD4+,CD8+) and CD4+/CD8+ ratio were detected with flow cytometry.The Mini-Mental State Examination (MMSE) was used to test the cognitive function of the patients at T0,T4 and 7 d after operation (T5).Results Compared with T0,the percentages of CD3+,CD4+ cells and CD4+/CD8+ in groups C,W and P were significantly decreased,the plasma concentrations of IL-6 and TNF-α significantly increased at T1-T4,concentration of NSE and S100 protein were significantly increased at T2 and T3 (P<0.05).the percentages of CD3+,CD4+T lymphocyte and CD4+/CD8+ ratio in groups W and P at T2,T3 and group WP at T1-T4 was significantly higher than that of group C,the concentration of IL-6,TNF-α,NSE and S100β protein content was significantly lower than in group C (P<0.05);the percentages of CD3+,CD4+T lymphocyte and CD4+/CD8+ ratio in group WP was significantly higher than those of groups W and P,the concentrations of TNF-α,IL-6,NSE and S100β protein content was significantly lower than those of group W and P at T2,T3 (P<0.05).Compared with T0,MMSE score in group C was significantly lower at T4,T5 (P<0.05).MMSE score of groups W,P and WP was significantly higher than that of group C at T4 (P<0.05).MMSE score of group WP was significantly higher than those of groups W and P at T4 (P<0.05).Conclusion Ulinastatin combined with parecoxib sodium ameliorates early cellular immunology function and cognitive function in elderly patients undergoing total hip replacement,and it is more effective than using ulinastatin or parecoxib sodium alone.
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Objective To study the effect of electroacupuncture pretreatment on cognitive function in aged rats and its possible mechanism. Methods 60 healthy male SD rats were randomly divided into 3 groups(n =20):control group (group C),simple operation group (S group),operation + electroacupuncture stimulation group (E Group),E group in the preoperative electroacupuncture stimulation Baihui、Neiguan、Qu pool and Zusanli,1 d,continuous stimulation 7 d. Group S and E were treated with hepatic ischemia-reperfusion. The water maze test (MWN)was performed at 1d before operation and 1,3,5 d and 7 d after operation,and the escape latency and swimming distance were recorded. The expression of Wnt protein ,β-catenin and phosphorylated glycogen synthase kinase-3β(p-GSK-3β) in cerebrospinal fluid were measured. Results Compared with group C ,the escape latency and swimming distance were significantly prolonged in group S and E at 1-7d(P<0.05),and the contents of Aβand p-tau-181 in S and E group were increased(P<0.05),the contents of Wnt protein,β-catenin protein and p-GSK-3β protein in group E were significantly increased (P < 0.05),and the contents of Wnt protein ,β-catenin and p-GSK-3βprotein in group S were significantly decreased(P<0.05);Compared with group S,the escape latency and swimming distance were significantly shortened in group E (P < 0.05),the levels of Aβ and p-tau-181 protein in group E were decreased(P<0.05),and Wnt protein andβ-catenin protein in group E were significantly lower than those in group E (P < 0.05),and p-GSK-3β protein were significantly increased (P <0.05). Conclusion Pretreatment with electroacupuncture can significantly improve the cognitive function of aged rats,the mechanism may be related to the activation of Wnt/β-catenin signaling pathway.
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Objective To study the effect of electroacupuncture pretreatment on cognitive function in aged rats and its possible mechanism. Methods 60 healthy male SD rats were randomly divided into 3 groups(n =20):control group (group C),simple operation group (S group),operation + electroacupuncture stimulation group (E Group),E group in the preoperative electroacupuncture stimulation Baihui、Neiguan、Qu pool and Zusanli,1 d,continuous stimulation 7 d. Group S and E were treated with hepatic ischemia-reperfusion. The water maze test (MWN)was performed at 1d before operation and 1,3,5 d and 7 d after operation,and the escape latency and swimming distance were recorded. The expression of Wnt protein ,β-catenin and phosphorylated glycogen synthase kinase-3β(p-GSK-3β) in cerebrospinal fluid were measured. Results Compared with group C ,the escape latency and swimming distance were significantly prolonged in group S and E at 1-7d(P<0.05),and the contents of Aβand p-tau-181 in S and E group were increased(P<0.05),the contents of Wnt protein,β-catenin protein and p-GSK-3β protein in group E were significantly increased (P < 0.05),and the contents of Wnt protein ,β-catenin and p-GSK-3βprotein in group S were significantly decreased(P<0.05);Compared with group S,the escape latency and swimming distance were significantly shortened in group E (P < 0.05),the levels of Aβ and p-tau-181 protein in group E were decreased(P<0.05),and Wnt protein andβ-catenin protein in group E were significantly lower than those in group E (P < 0.05),and p-GSK-3β protein were significantly increased (P <0.05). Conclusion Pretreatment with electroacupuncture can significantly improve the cognitive function of aged rats,the mechanism may be related to the activation of Wnt/β-catenin signaling pathway.
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Objective To investigate the effects of different duration hypotension thresholds on p-Tau-181 and Aβ-42 protein expression and cognition in rats. Methods Thirty-nine healthy male SD rats were randomly di-vided into 4 groups:the control group(group C,n=9),the hypotension group(groupA1、A2、A3 ,n=10). The blood pressure of groupA1、A2、A3 was measured in different time of 2 h、4 h、6 h ,for 5 days. The antihyperten-sive group of mean arterial pressure(MAP)were maintained in the 50~55 mmHg safe range. Morris water maze was used to detect the spatial learning and memory ability of rats. The levels of Aβ42 and p-Tau-181 were detected by ELISA. Results There was no significant difference in mortality of rats in each group (P > 0.05). Compared with the group C,the escape latency and swimming distance of A2 group and A3 group were increased(P<0.05). In 3~7 days after operation,the cerebrospinal fluid P-Tau-181 and Aβ42 protein expression increased in the A2 group and A3 group compared with the A1 group(P<0.05). The escape latency and swimming distance of the A2 group and the A3 group were significantly longer than those in the control group. Aβ42 and p-Tau-181 were signifi-cantly increased in A3 group(P < 0.05). Compared with the A2 group,the increase of Aβ42 and p-Tau-181 in the A3 group was not significant(P<0.05). Conclusion Long-term controlled hypotension may lead to postoper-ative cognitive dysfunction which may relate to the increase of Aβ42 and p-Tau-181 protein expression.
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Objective To investigate the effects of Saikosaponin A (SSA)on cognitive function and cAMP/CREB signaling pathway and expression of BDNF in mice after traumatic brain injury. Methods Sixty SD male mice were randomized into three groups:shame operation group (group S, n =20),trauma group (group T,n =20)and SSA treatment group (group A,n =20).Mice received an administration of SSA 5 mg/kg (group A)or equal volume saline (group S,group T)immediately and once daily for 5 consecutive days after trauma.The cognitive function was detected by Morris wa-ter maze test on day 1,3,7 and 14 after trauma.The hippocampal tissues were harvested after be-havioral tests and homogenized for measuring the levels of brain derived neurophic factor (BDNF)and cyclic AMP (cAMP)by ELISA as well as the levels of cAMP-response element binding protein (CREB)and phosphorylation-cAMP-response element binding protein (pCREB)by western bolt. Results Compared with group S,the escape latency and swimming distance were significantly pro-longed in group T on day 1,3,7 and 14 and group A on day 1,3 after trauma (P <0.05 );while compared with group T,they were significantly shorter in group A on day 7,14 after trauma (P <0.05).Compared with group S,the levels of BDNF,cAMP,CREB and pCREB were significantly de-creased in group T(P < 0.05 ).Compared with group T,the levels of BDNF,cAMP,CREB and pCREB were significantly increased in group A (P <0.05).Conclusion SSA can significantly improve cognitive dysfunction in mice after traumatic brain injury,and the mechanism may be related to the activation of cAMP/CREB signaling pathway and up-regulation of BDNF.
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Objective To investigate the effects of enhanced recovery after surgery (ERAS) pathway on early cognitive function of post-hepatectomy patients after hepatectomy.Methods Ninety-six patients undergoing elective hepatectomy for liver cancer were randomly assigned into two groups:group ERAS,n =48 and group C,n =48.patients in group ERAS accepted perioperative and anaes-thetic optimization of enhanced recovery after surgery pathway,and patients in group C received peri-operative and anaesthetic management of normal surgery concept.The mini-mental state examination (MMSE)was used to test the cognitive function of the patients one day before operation (T0 ),one day after operation (T4 ),three days after operation (T5 )and seven days after operation (T6 ),and the blood levels of S100βprotein,neuron-specific enolase(NSE),IL-1β,IL-6,and TNF-α were de-tected at T0 ,30 minutes after operation (T1 ),6 hours after operation (T2 ),12 hours after operation (T3 )and T4 .Results Compared with group C,MMSE scores in group ERAS were increased at T4 ,T5 , the blood levels of S100βprotein,IL-1βand IL-6 in group ERAS were decreased at T1 ,T2 ,the blood levels of NSE in group ERAS were decreased at T2 ,T3 ,the blood levels of TNF-αin group ERAS were decreased at T1-T3 ;Compared with the baseline value at T0 ,MMSE scores were decreased at T4 ,T5 in group C and decreased at T4 in group ERAS,the blood levels of S100 βprotein in two groups were increased at T1-T3 , the blood levels of NSE in two groups were increased at T2-T4 ,the blood levels of IL-1β,IL-6,and TNF-αin two groups were increased at T1-T4 ;and the postoperative length of stay in group ERAS were decreased. Conclusion Enhanced recovery after surgery pathway is helpful in improving early postoperative cognitive function of patients after hepatectomy,and the mechanism may be related to decreased the blood levels of S100βprotein,NSE,IL-1β,IL-6 and TNF-α.
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Objective To explore the similarities and differences between finger photoplethysmogram (PPG) and CSI in monitoring the depth of anaesthesia in Chinese adults under general anaesthesia. Methods Ninety-three patients, ASA ⅠorⅡ, aged 20-67, under general anaesthesia were enrolled. Anaesthesia was induced with target-controlled infusion (TCI) of propofol. The initial TCI concentration of propofol was set at 0.5 mg·L-1 followed by increments of 0.5 mg·L-1 at 3-min interval until the score of Modified Observer's Assessment of Alertness/Sedation Scale (MOAAS)reached 0. PPG and CSI were continuously monitored and their values were recorded every 2-4 seconds. MOAAS was recorded every 30 seconds to evaluate the sedation level in the study period. ResultsFor the periodfrom pre-induction to pre-intubation, the difference of photoplethysmogram amplitudevalues had statistical significance between level 4 and level 3, level 3 and level 2 of MOAAS (P<0.05). CSIvalues declined along with the decrease of MOAAS levels and were statistically different between every two neighboring levels of MOAAS (P < 0.05). Photoplethysmogram amplitude (PPGA) and pulse beat interval (PBI) values showed significant differences before and after intubation, pre- and post-incision (P < 0.05). Conclusions PPGA and PBI appear to be suitable to monitor the nociceptive component of balanced general anesthesia , while the CSI exhibits a good performance in monitoring the sedation or hypnotic component of balanced general anesthesia , thusthe combination of PPGA and CSI would benefit the monitoring of the adequacy of depth of anaesthesia.
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Objective To investigate the role of AKT/GSK3β/mTOR signaling molecule in myocardial protection of sevoflurane postconditioning.Methods Thirty-nine male Sprague-Dawley rats,weighing 200-250 g,installed in vivo myocardial ischemia-reperfusion model by left anterior de-scending coronary occlusion for 30 min.Rat hearts were randomly divided into 3 groups (n = 13 ):sham control group (group Sham),purely ischemia-reperfusion group (group IR),sevoflurane post-conditioning group (group SPC).With the exception of group Sham,each group was subjected to oc-clusion for 30 min followed by 2 h reperfusion.Group SPC was subjected to sevoflurane postcondi-tioning:2.4% sevoflurane was inhaled for 1 5 min starting from the end of ischemia until 1 5 min after beginning of reperfusion,while 33% oxygen was inhaled in the other groups.At the end of 2 h reper-fusion,cardiac function was evaluated by two-dimensional echocardiography,myocardial infarction size was measured by using 1% 2,3,5-triphenyltetrazolium chloride triazole (TTC),myocardial ultra-structural alterations was detected by transmission electron microscopy (TEM),cardiomyocytes ap-optosis was examined by terminal deoxynucleotidyl nickend labeling (TUNEL),the expressions of p-AKT/t-AKT, p-GSK3β/t-GSK3β, p-mTOR/t-mTOR,Bcl-2 and Bax proteins was measured by Western blot.Results Compared with group Sham,cardiac function was deteriorated,myocardial in-farct size was increased,cardiomyocyte mitochondrial damage was increased,positive apoptotic car-diomyocyte was increased,the expression of Bcl-2 was down-regluated,and the expressions of p-AKT/t-AKT,p-GSK3β/t-GSK3β,p-mTOR/t-mTOR and Bax were up-regluated in group IR (P <0.05).Compared with group IR,cardiac function was improved,myocardial infarct size was de-creased,cardiomyocyte mitochondrial damage was decreased,positive apoptotic cardiomyocyte was decreased,the expression of Bax was down-regluated,and the expressions of p-AKT/t-AKT,p-GSK3β/t-GSK3β,p-mTOR/t-mTOR and Bcl-2 were up-regluated in group SPC (P < 0.05 ). Conclusion Sevoflurane postconditioning can mitigate ischemia-reperfusion injury to in vivo rat hearts,decreased cardiomyocyte mitochondrial damage,inhibited cardiomyocyte apoptosis,and its mechanism was related to the activation of AKT/GSK3β/mTOR signaling molecule.
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Objective To evaluate the role of C-Jun N-Terminal kinase (JNK) signaling pathway in dexmedetomidine-induced reduction of spinal neurotoxicity induced by lidocaine in rats.Methods Seventy-two adult male Sprague-Dawley rats, weighing 280-320 g, in which intrathecal catheters were successfully implanted without complications, were randomly divided into 6 groups (n =12 each) using a random number table: control group (group C);SP600125 (JNK signaling pathway blocker) group (group SP);dexmedetomidine group (group D);lidocaine group (group L);dexmedetomidine + lidocaine group (group DL);SP600125+lidocaine group (group SPL).Dimethyl sulfoxide (DMSO) 20 μl was injected intrathecally in group C.SP600125 30 μg and 10% lidocaine 20 μl were injected intrathecally in SP and L groups, respectively.At 20 min after intrathecal injection of 10% lidocaine, dexmedetomidine 75 μg/kg was injected intraperitoneally in group DL, and SP600125 30 μg was injected intrathecally in group SPL.Dexmedetomidine 75 μg/kg was injected intraperitoneally in group D.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawal latency (TWL) were measured before intrathecal catheters were implanted (T0), before intrathecal administration (T1), and at 4, 8 and 12 h and 1, 2, 3, 4, 5 and 6 days after intrathecal administration (T2-10).At 24 h after intrathecal administration, 6 rats randomly selected from each group were sacrificed.The lumbar segment (L4-5) of the spinal cord was removed for detection of cell apoptosis (by TUNEL) and phosphorylated JNK (p-JNK) expression (by Western blot).The apoptotic index was calculated.Results Compared with group C, no significant change was found in the MWT, TWL, apoptotic index and expression of p-JNK in SP and D groups (P>0.05), the MWT at T2-8 in group L, at T2-6 in group DL and at T2-5 in group SPL were significantly increased, the TWL at T2-8 in group L, at T2-5 in group DL and at T2-4 in group SPL were prolonged, and the apoptotic index and expression of p-JNK were increased in DL, SPL and L groups (P<0.05).Compared with group L, the MWT was significantly decreased, and the TWL was shortened at T2-8, and the apoptotic index and expression of p-JNK were decreased in DL and SPL groups (P<0.05).Conclusion The mechanism by which dexmedetomidine mitigates spinal neurotoxicity induced by lidocaine is related to inhibited activation of JNK signaling pathway in rats.
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Objective To investigate the effects of lithium chloride pretreatnent on cognitive function after laparotomy in aged rats. Methods Forty-eight male SD rats aged 18 months, weighing 550-700 g were randomly divided into 3 groups (n = 16 each): group Ⅰ control (group C); group Ⅱ operation (group O) and group Ⅲ lithium chloride preconditioning (group L). In group L lithium chloride 2 mmol/kg was injected intraperitoneally (IP) once a day for 7 consecutive days before exploratory laparotomy. In group C and group O equal volume of normal saline was injected instead of lithium chloride. The animals were anesthetized with IP 2 % pentobarbital 0.25 ml/100 g. Morris water-maze (MWM) test was performed at day 4-6 after operation in 8 animals in each group. Another 8 animals were killed at 24 h after operation and their brains were immediately removed for determination of IL-1β content and expression of total glycogen synthase kinase-3β (GSK-3β) and p-GSK-3β in hippocampus by ELISA and Western blot respectively. Results Compared with group C the escape latency and swimming distance were both significantly prolonged at day 4-6 after operation in group O, while in group L only swimming distance was prolonged at day 4 after operation. The IL-1β content in hippocampus was significantly higher and the expression of p-GSK-3β was significantly lower in group O than in group C and L. There was no significant difference in total GSK-3β among the 3 groups. Conclusion Lithium chloride pretreatment can improve the cognitive function after laparotomy in aged rats by inhibiting GSK-3β activity and attenuating inflammatory response in hippocampus.
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Objective To investigate the effect of oleanolic acid pretreatment on hepatic ischemiareperfusion (I/R) injury in rats. Methods One hundred and twenty-eight male SD rats weighing 230-250 g were randomly divided into 4 groups (n = 32 each): sham operation group (group S), I/R group, 0.5% sodium carboxymethyl cellulose group (group CMC) and oleanolic acid preconditioning (group OA). Partial liver ischemia was produced by clamping hepatic portal vein and hepatic arteries for 60 min with atraumatic mini-clamp, followed by 12 h of reperfusion in group I/R, CMC and OA. Oleanolic acid suspension 100 mg/kg was infused intragastrically in group OA, while the equal volume of 0.5% CMC-Na (in group CMC) and drinking water (in group S and I/R) was infused intragastrically instead once a day for 7 days, and then hepatic I/R was performed at day 8. The left liver was removed and blood sample was taken from inferior vena cava at 0, 3, 6 and 12 h ofreperfusion for determination of serum alanine amino transferase (ALT) activity, superoxide dismutase (SOD)activity, malondialdehyde (MDA) and glutathione (GSH) content, and expression of phospho-phosphatidylinositol3-kinase (p-PI3K), Akt, p-Akt, Bcl-2, Bax, p-Bad and Bad in the liver, and microscopic examination. Results Serum ALT activity and MDA content in the liver were significantly increased, SOD activity and GSH content in the liver were significantly decreased, expression of p-PI3K, p-Akt, Bax, Bad and p-Bad was up-regulated, and Bcl-2 expression was down-regulated during reperfusion in group I/R, CMC and OA as compared with group S (P <0.05). Compared with group I/R, serum ALT activity and MDA content in the liver were significantly decreased, SOD activity and GSH content in the liver were significantly increased, expression of p-PI3K, p-Akt,Bcl-2 and p-Bad was up-regulated, and expression of Bad and Bax was down-regulated during reperfusion in group OA (P < 0.05), but no significant change was found in the indexes mentioned above in group CMC (P > 0.05).Serum ALT activity and MDA content in the liver were significantly lower, SOD activity and GSH content in the liver were significantly higher, expression of p-PI3K, p-Akt, Bcl-2 and p-Bad was significantly higher, and expression of Bad and Bax was significantly lower during reperfusion in group OA than in group CMC (P < 0.05).The pathological changes in the liver were milder in group OA than in group I/R. Conclusion Oleanolic acid pretreatment can alleviate hepatic I/R injury by activating PI3K/Akt signaling pathway and inhibiting apoptosis.