Objective:To evaluate the effect of dexmedetomidine on the viability of dopaminergic neurons in the ventral tegmental area (VTA) of morphine-addicted mice.Methods:Experiment Ⅰ Thirty SPF healthy adult male C57BL/6 mice, aged 8 weeks, weighing 20-25 g, were divided into 3 groups ( n=10 each) using the random number table method: normal saline group (NS group), dexmedetomidine 50 μg/kg group (DEX50 group), and dexmedetomidine 100 μg/kg group (DEX100 group). A morphine addiction model was established by intraperitoneal injection of increasing doses of morphine (10, 20, 30, 40, 50 and 50 mg/kg) for 6 consecutive days in mice. After the successful establishment of the model, dexmedetomidine 50 and 100 μg/kg were intraperitoneally injected for 14 consecutive days in group DEX50 and group DEX100 respectively, while normal saline was given instead in group C. The conditioned place preference (CPP) experiment was conducted every other day. Experiment Ⅱ Thirty SPF healthy adult male C57BL/6 mice, aged 8 weeks, weighing 20-25 g, were divided into 3 groups ( n=10 each) by the random number table method: control group (C group), morphine group (Mor group) and dexmedetomidine 50 μg/kg group (DEX50 group). Normal saline was intraperitoneally injected for 10 consecutive days in group C. Morphine with increasing doses was intraperitoneally injected for 6 days, and then normal saline was intraperitoneally injected for 4 consecutive days in group Mor. Morphine with increasing doses was intraperitoneally injected for 6 days, and then dexmedetomidine 50 μg/kg was intraperitoneally injected for 4 consecutive days in group DEX50. The mice were anesthetized at 90 min after the last intraperitoneal injection, brain tissues were harvested, and the corresponding brain slices of the VTA were selected for c-Fos immunofluorescence staining. Experiment Ⅲ Ten dopamine transporter-Cre recombinase mice were divided into 2 groups ( n=5 each) by the random number table method: morphine group (Mor group) and morphine+ dexmedetomidine 50 μg/kg group (Mor+ DEX group). Stereotaxic viral injection was performed in the brain. rAAV-EF1α-DIO-GCaMP6s was injected into the VTA and an optical fiber was implanted. Three weeks later, a morphine addiction model was established based on Experiment Ⅰ for the CPP experiment, morphine was intraperitoneally injected in group Mor, and morphine and dexmedetomidine were intraperitoneally injected in group Mor+ DEX. The viral fluorescence signals were recorded at 5 min before and 20 min after the drug administration in the three groups. Results:Experiment Ⅰ There was no statistically significant difference in the CPP scores after developing the morphine addiction model among the three groups ( P>0.05). Compared with group NS, the CPP scores were significantly decreased at 4-14 days of the continuous administration in group DEX50 and group DEX100 ( P<0.05). Experiment Ⅱ Compared with group C, the number of c-Fos positive cells in the VTA was significantly increased in group Mor ( P<0.05). Compared with group Mor, the number of c-Fos positive cells in the VTA was significantly decreased in group DEX ( P<0.05). Experiment Ⅲ Compared with that before administration, the calcium signals of dopaminergic neurons in the VTA were significantly enhanced in group Mor ( P<0.05), and no statistically significant difference was found in the calcium signals of dopaminergic neurons in the VTA in group Mor+ DEX ( P>0.05). Compared with group Mor, no statistically significant difference was found in the calcium signals of dopaminergic neurons in the VTA before drug administration ( P>0.05), and the calcium signals of dopaminergic neurons in the VTA were significantly weakened after administration in group Mor+ DEX ( P<0.05). Conclusions:The mechanism by which dexmedetomidine promotes the extinction of morphine addiction is related to the inhibition of the viability of dopaminergic neurons in the VTA of mice.

Objective To observe the effect of resveratrol on intestinal ischemia reperfusion(IIR)inju-ry and its correlation with ferroptosis.Methods The mice IIR injury model was constructed.The mice were divided into the sham operation group(group S),IIR injury group(group D),IIR injury+resveratrol group(group R),IIR injury+ferroptosis inducer group(group F),IIR injury treatment+resveratrol+ferropto-sis inducer group(group R+F).The various groups adopted different drug doses and methods.The intestinal tissue sections were taken for performing the HE staining and the pathological changes were observed by the light microscope.ELISA was used to detect the levels of malondialdehyde(MDA),ferrous ion(Fe2+),gluta-thione(GSH)and super oxide dismutase(SOD).Western blot was used to detect the expression levels of glu-tathione peroxidase 4(GPX4)and acyl-coasynthetasling-chain family member 4(ACSL4)protein.Results Com-pared with the group S,the small intestine tissue damage in the group D,R,F and R+F was aggravated,the Chiu's score,MDA and Fe2+level s were increased,GSH and SOD levels were decreased(P＜0.05),the AC-SL4 protein expression was up-regulated,GPX4 protein expression was down-regulated,and the differences were statistically significant(P＜0.05).Compared with the group D,the small intestine tissue in the group R appeared subapical villous injury,Chiu's score,MDA and Fe2+levels were decreased,the GSH and SOD levels were increased,the ACSL4 protein expression was down-regulated and GPX4 protein expression was up-regu-lated,and the differences were statistically significant(P＜0.05);the small intestine tissue in the group F ap-peared villi fall off accompanied by bleeding and ulcer formation,Chiu's score,MDA level and Fe2+level were increased,GSH and SOD levels were decreased,ACSL4 protein expression level was up-regulated,GPX4 pro-tein expression was down-regulated,and the differences were statistically significant(P＜0.05).Compared with the R group,the small intestine tissue in the R+F group appeared a large number of villi and lamina pro-pria,which were damaged and fell off,Chiu's score,MDA and Fe2+levels were increased,GSH and SOD lev-els were decreased,ACSL4 protein expression was up-regulated and GPX4 protein expression was down-regu-lated,and the differences were statistically significant(P＜0.05).Conclusion Resveratrol may alleviate intes-tinal injury caused by IIR through antioxidation action and inhibiting ferroptosis.

Objective:To evaluate the effect of dexmedetomidine on the viability of dopaminergic neurons in the ventral tegmental area (VTA) of morphine-addicted mice.Methods:Experiment Ⅰ Thirty SPF healthy adult male C57BL/6 mice, aged 8 weeks, weighing 20-25 g, were divided into 3 groups ( n=10 each) using the random number table method: normal saline group (NS group), dexmedetomidine 50 μg/kg group (DEX50 group), and dexmedetomidine 100 μg/kg group (DEX100 group). A morphine addiction model was established by intraperitoneal injection of increasing doses of morphine (10, 20, 30, 40, 50 and 50 mg/kg) for 6 consecutive days in mice. After the successful establishment of the model, dexmedetomidine 50 and 100 μg/kg were intraperitoneally injected for 14 consecutive days in group DEX50 and group DEX100 respectively, while normal saline was given instead in group C. The conditioned place preference (CPP) experiment was conducted every other day. Experiment Ⅱ Thirty SPF healthy adult male C57BL/6 mice, aged 8 weeks, weighing 20-25 g, were divided into 3 groups ( n=10 each) by the random number table method: control group (C group), morphine group (Mor group) and dexmedetomidine 50 μg/kg group (DEX50 group). Normal saline was intraperitoneally injected for 10 consecutive days in group C. Morphine with increasing doses was intraperitoneally injected for 6 days, and then normal saline was intraperitoneally injected for 4 consecutive days in group Mor. Morphine with increasing doses was intraperitoneally injected for 6 days, and then dexmedetomidine 50 μg/kg was intraperitoneally injected for 4 consecutive days in group DEX50. The mice were anesthetized at 90 min after the last intraperitoneal injection, brain tissues were harvested, and the corresponding brain slices of the VTA were selected for c-Fos immunofluorescence staining. Experiment Ⅲ Ten dopamine transporter-Cre recombinase mice were divided into 2 groups ( n=5 each) by the random number table method: morphine group (Mor group) and morphine+ dexmedetomidine 50 μg/kg group (Mor+ DEX group). Stereotaxic viral injection was performed in the brain. rAAV-EF1α-DIO-GCaMP6s was injected into the VTA and an optical fiber was implanted. Three weeks later, a morphine addiction model was established based on Experiment Ⅰ for the CPP experiment, morphine was intraperitoneally injected in group Mor, and morphine and dexmedetomidine were intraperitoneally injected in group Mor+ DEX. The viral fluorescence signals were recorded at 5 min before and 20 min after the drug administration in the three groups. Results:Experiment Ⅰ There was no statistically significant difference in the CPP scores after developing the morphine addiction model among the three groups ( P>0.05). Compared with group NS, the CPP scores were significantly decreased at 4-14 days of the continuous administration in group DEX50 and group DEX100 ( P<0.05). Experiment Ⅱ Compared with group C, the number of c-Fos positive cells in the VTA was significantly increased in group Mor ( P<0.05). Compared with group Mor, the number of c-Fos positive cells in the VTA was significantly decreased in group DEX ( P<0.05). Experiment Ⅲ Compared with that before administration, the calcium signals of dopaminergic neurons in the VTA were significantly enhanced in group Mor ( P<0.05), and no statistically significant difference was found in the calcium signals of dopaminergic neurons in the VTA in group Mor+ DEX ( P>0.05). Compared with group Mor, no statistically significant difference was found in the calcium signals of dopaminergic neurons in the VTA before drug administration ( P>0.05), and the calcium signals of dopaminergic neurons in the VTA were significantly weakened after administration in group Mor+ DEX ( P<0.05). Conclusions:The mechanism by which dexmedetomidine promotes the extinction of morphine addiction is related to the inhibition of the viability of dopaminergic neurons in the VTA of mice.

This study aims to gain insight into the DNA-specific recognition mechanism of c-Myb transcription factor during the regulation of cell early differentiation and proliferation. Therefore, we chose the chicken myeloid gene, mitochondrial import protein 1 (mim-1), as a target to study the binding specificity between potential dual-Myb-binding sites. The c-Myb-binding site in mim-1 is a pseudo-palindromic sequence AACGGTT, which contains two AACNG consensuses. Simulation studies in different biological scenarios revealed that c-Myb binding with mim-1 in the forward strand (complex F) ismore stable than that inthereverse strand (complex R). The principal component analysis (PCA) dynamics trajectory analyses suggested an opening motion of the recognition helices of R2 and R3 (R2R3), resulting in the dissociation of DNA from c-Myb in complex R at 330 K, triggered by the reduced electrostatic potential on the surface of R2R3. Furthermore, the DNA confirmation and hydrogen-bond interaction analyses indicated that the major groove width of DNA increased in complex R, which affected on the hydrogen-bond formation ability between R2R3 and DNA, and directly resulted in the dissociation of DNA from R2R3. The steered molecular dynamics (SMD) simulation studies also suggested that the electrostatic potential, major groove width, and hydrogen bonds made major contribution to the DNA‍-specific recognition. In vitro trials confirmed the simulation results that c-Myb specifically bound to mim-1 in the forward strand. This study indicates that the three-dimensional (3D) structure features play an important role in the DNA-specific recognition mechanism by c-Myb besides the AACNG consensuses, which is beneficial to understanding the cell early differentiation and proliferation regulated by c-Myb, as well as the prediction of novel c-Myb-binding motifs in tumorigenesis.
Molecular Dynamics Simulation ; Consensus ; DNA ; Hydrogen

Objective:To assess the accuracy and practicability of HaiMed refractory wound artificial intelligence assisted system in wound measurement.Methods:Twenty patients with chronic wounds who were diagnosed and treated from January 2019 to August 2019 in the Plastic Surgery Department of Peking University Third Hospital, including 12 males and 8 females, aged 20-76 years old. The cases included 9 poorly healed wounds, 6 diabetic foot wounds, 4 cases of pressure sores, and 1 case of tumor wounds. The traditional transparent film method and HaiMed system were used to measure the wound area of 20 cases. A paired t-test was performed on the measurement result of the two groups of wound area, and the accuracy and stability of the HaiMed system were statistically analyzed by Spearman simple correlation analysis, Bland-Altman evaluation and coefficient of variation. P<0.05 indicated that the difference was statistically significant. Results:Compared with traditional measurement tools, HaiMed system had no statistically significant difference in wound area measurement ( t=1.997, P=0.060). The Spearman correlation coefficient ( r=0.998) of the two method was consistent. Bland-Altman’s evaluation showed that all scattered points fell within the 95% consistency limit, and the HaiMed system was accurate and reliable. The minimum coefficient of variation of the transparent film hem method group was 0.41%, the maximum was 4.03%, and the average was 1.67%; the coefficient of variation of the HaiMed group was minimum 0.15%, the maximum was 2.31%, and the average was 0.60%. The two had good consistency, and the HaiMed system had higher stability than traditional measurement method. Conclusions:HaiMed system measures the wound area with high accuracy and good stability, especially for superficial wounds. It can be easily and quickly evaluated. HaiMed system is a new and reliable wound measurement tool.

Objective:To assess the accuracy and practicability of HaiMed refractory wound artificial intelligence assisted system in wound measurement.Methods:Twenty patients with chronic wounds who were diagnosed and treated from January 2019 to August 2019 in the Plastic Surgery Department of Peking University Third Hospital, including 12 males and 8 females, aged 20-76 years old. The cases included 9 poorly healed wounds, 6 diabetic foot wounds, 4 cases of pressure sores, and 1 case of tumor wounds. The traditional transparent film method and HaiMed system were used to measure the wound area of 20 cases. A paired t-test was performed on the measurement result of the two groups of wound area, and the accuracy and stability of the HaiMed system were statistically analyzed by Spearman simple correlation analysis, Bland-Altman evaluation and coefficient of variation. P<0.05 indicated that the difference was statistically significant. Results:Compared with traditional measurement tools, HaiMed system had no statistically significant difference in wound area measurement ( t=1.997, P=0.060). The Spearman correlation coefficient ( r=0.998) of the two method was consistent. Bland-Altman’s evaluation showed that all scattered points fell within the 95% consistency limit, and the HaiMed system was accurate and reliable. The minimum coefficient of variation of the transparent film hem method group was 0.41%, the maximum was 4.03%, and the average was 1.67%; the coefficient of variation of the HaiMed group was minimum 0.15%, the maximum was 2.31%, and the average was 0.60%. The two had good consistency, and the HaiMed system had higher stability than traditional measurement method. Conclusions:HaiMed system measures the wound area with high accuracy and good stability, especially for superficial wounds. It can be easily and quickly evaluated. HaiMed system is a new and reliable wound measurement tool.

Objective To summarize our experience with tubular gastric elongation surgery for management of insufficient gastric length for high esophageal-gastric anastomosis following esophageal carcinoma resection. Methods From September, 2015 to October 2016, 5 patients with esophageal cancer were treated in our department, including two with cervical esophageal cancer and 3 with thoracic esophageal cancer. The patients with cervical esophageal cancer underwent pharyngeal resection, total laryngectomy, esophageal varus extubation and gastric oropharyngeal anastomosis, and the patients with thoracic esophageal cancer underwent esophageal cancer resection with incisions on the left neck, the right chest and the median abdomen. During the surgery, the length of the stomach was found insufficient to allow routine oropharyngeal anastomosis, and tubular gastric elongation was conducted to extend the tubular stomach to enable successful completion of the surgery. Results All the patients recovered smoothly after the surgery and were discharged after 2-3 weeks. Conclusion Tubular gastric elongation surgery can be a good choice for high esophageal-gastric anastomosis after resection of esophageal cancer in cases of insufficient tubular stomach length or high tension at the anastomosis.

Objective To summarize our experience with tubular gastric elongation surgery for management of insufficient gastric length for high esophageal-gastric anastomosis following esophageal carcinoma resection. Methods From September, 2015 to October 2016, 5 patients with esophageal cancer were treated in our department, including two with cervical esophageal cancer and 3 with thoracic esophageal cancer. The patients with cervical esophageal cancer underwent pharyngeal resection, total laryngectomy, esophageal varus extubation and gastric oropharyngeal anastomosis, and the patients with thoracic esophageal cancer underwent esophageal cancer resection with incisions on the left neck, the right chest and the median abdomen. During the surgery, the length of the stomach was found insufficient to allow routine oropharyngeal anastomosis, and tubular gastric elongation was conducted to extend the tubular stomach to enable successful completion of the surgery. Results All the patients recovered smoothly after the surgery and were discharged after 2-3 weeks. Conclusion Tubular gastric elongation surgery can be a good choice for high esophageal-gastric anastomosis after resection of esophageal cancer in cases of insufficient tubular stomach length or high tension at the anastomosis.

Aim To establish the adherence of H pylori to MKN45 cell model for screening and evaluating anti-adhesive drugs.Methods H pylori suspension was incubated with FITC solution in different conditions(FITC concentration and incubation time)to optimize the labeling conditions.At the same time,Gram staining was used to determine the optimal adhesion time of H pylori to MKN45 cells.Results H pylori suspension(1?106 cuf?ml-1)incubating with FITC(5 mg?L-1)for 1 h could achieve the optimal effect for FITC-labeling H pylori.Besides,Gram staining indicated that the optimal adhesion time for H pylori to MKN45 cells was 1 h.Based on the model,the crude Aloe polysaccharide was evaluated for its anti-adhesive activity and the results showed it could significantly reduce the adherence of H pylori to MKN45 cells at the concentration of 1 g?L-1(P