Objective:To prepare the nanodrug paclitaxel dimer(PTX2)-loaded nanoparticles(NPs)using the block copolymer 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-polyethylene glycol 2000,(DSPE-PEG2000),and to explore the killing effect of PTX2 NPs on the human lung cancer A549 cells and its influence on apop to tis.Methods:The PTX2 NPs were prepared using nanoprecipitation method.Dynamic light scattering(DLS)was employed to determine the particle size distribution,and transmission electron microscope(TEM)was used to observe the ultrastructure of the nanoparticles.After treatment of 0 and 10 mmol·L-1 dithiothreitol(DTT),dialysis method was used to evaluate the in vitro drug release profile of PTX2 NPs.The cell counting kit-8(CCK-8)method was used to assess the survival rates of the A549 cells after treated with PTX2 and PTX2 NPs with different concentrations(0.000 1,0.001 0,0.010 0,0.100 0,and 1.000 0 μmol·L-1).The A549 cells were divided into control group,PTX2 group,and PTX2 NPs group.Live/dead staining method was used to detect the survival of the A549 cells in various groups,and flow cytometry was used to detect the apoptotic rates of the A549 cells in various groups.Results:The mean hydrodynamic diameter of PTX2 NPs was determined to be 144.7nmbyDLS.TheTEM imaging confirmed uniform spherical morphology of PTX2 NPs.In a reductive environment,the PTX2 NPs exhibited continuous drug release with total paclitaxel(PTX)release of 84％within 72 h.The results of CCK-8 method showed that both PTX2 and PTX2 NPs inhibited the proliferation of A549 cells in a dose-dependent manner.When the concentrations of PTX＜0.01 μmol·L-1,compared with PTX2 group,the survival rates of A549 cells in PTX2 NPs group were significantly decreased(P＜0.01 or P＜0.001).The live/dead staining results showed that compared with PTX2 group,the number of red fluorescence-labeled dead cells in PTX2 NPs group was increased.The flow cytometry results demonstrated that compared with control group and PTX2 group,the apoptotic rates of the A549 cells in PTX2 NPs group were significantly increased(P＜0.05 orP＜0.01).Conclusion:The PTX2-loaded nanoparticles PTX2 NPs are successfully prepared which exhibits responsive drug release and demonstrates a more significant killing effect on the human lung cancer A549 cells compared to PTX2.

Objective:To prepare the bacterial outer membrane vesicles(OMV)that can express programmed death ligand 1(PD-L1)nanobody on surface,and to discuss its structural characteristics,cell compatibility,intracellular distribution,and its blocking effect on the programmed cell death protein-1(PD-1)/PD-L1 signaling axis.Methods:The pET28a-ClyA-PD-L1nb prokaryotic expression vector was constructed and transformed into Escherichia coli BL21(DE3)competent cells;the OMV was isolated from the BL21(DE3)monoclonal colonies transformed with the PD-L1nb expression vector by ultracentrifugation;the protein purification was performed using the histidine(His)tag;transmission electron microscope and nanoparticle size analyzer were used to analyze and identify the OMV;the OMV isolated from the BL21(DE3)monoclonal colonies transformed with the PD-L1nb expression vector was used as experimental group;the OMV isolated from the untransformed BL21(DE3)monoclonal colonies was used as control group;Western blotting method was used to detect the expression levels of ClyA-PD-L1nb fusion protein in the OMV in two groups;cell counting kit-8(CCK-8)assay was used to detect the activities of mouse macrophage RAW 264.7 cells,mouse triple-negative breast cancer 4T1 cells,and human embryonic kidney HEK293T cells after treated with OMV;fluorescence imaging technology was used to observe the tumor cell endocytosis of OMV;flow cytometry was used to detect the binding effect of OMV to the PD-L1 on surface of the tumor cells in PBS group,OMV-PD-L1nb group,and aPD-L1+OMV-PD-L1nb group.Results:The sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)results showed that after induction of Escherichia coli,significantly thickened protein bands appeared near the predicted relative molecular mass(about 49 000),and after purification,no obvious impurity proteins existed in the lanes;the OMV-PD-L1nb with a size of about 120 nm was isolated by ultracentrifugation,and it presented a uniform spherical structure under transmission electron microscope;the Western blotting results showed that the specific band of ClyA-PD-L1nb was detected in the OMV in experimental group;the CCK-8 assay results showed that after treated with different concentrations of OMV,the viabilities of the RAW 264.7 cells,4T1 cells,and HEK293T cells were all close to 100％;the fluorescence imaging results showed that OMV-PD-L1nb was endocytosed by 4T1 cells and dispersed in the cytoplasm;compared with OMV-PD-L1nb group,the average fluorescence intensity in the cells in aPD-L1+OMV-PD-L1nb group was significantly decreased(P＜0.001).Conclusion:The OMV surface-displaying PD-L1nb,OMV-PD-L1nb,is successfully prepared and isolated;OMV-PD-L1nb shows good compatibility on mouse macrophage cells,tumor cells,and human embryonic kidney cells,can be endocytosed by tumor cells,and successfully blocks the PD-1/PD-L1 signaling pathway.

Objective To explore the impact of pre positioned nasopharyngeal airway combined with high head pre inhalation of oxygen on lung oxygenation and blood gas analysis indicators in morbid obese patients undergoing laparoscopic weight loss surgery.Methods 100 morbid obesity patients from January 2020 to April 2022 planned to undergo elective laparoscopic weight loss surgery were selected as the study subjects.All the patients were divided into two groups according to the random number table method:group A with a head height of 25° and a pre installed nasopharyngeal airway;group B with a head height of 25° and no pre installed nasopharyngeal airway,with 50 patients in each group.Two groups were pre oxygenated for 3 min before undergoing intravenous anesthesia to induce tracheal intubation.Observe and record the pH value,partial pressure of oxygen in arterial blood(PaO2),partial pressure of carbon dioxide(PCO2),partial pressure of oxygen in arterial blood/fractional concentration of inspiratory oxygen(PaO2/FiO2)as well as the ratio of arterial pressure to alveolar oxygen partial pressure(a/APO2)of the two groups of patients who breathed air(T0)after entering the room,ventilated with mask positive pressure for 3 min(T1),and intubated with trachea for 3 min(T2).Record plateau pressure(Pplat),peak airway pressure(Ppeak),and dynamic lung compliance(Cdyn)at T1,T2,and 5 min after pneumoperitoneum(T3).Record the time for percutaneous arterial oxygen saturation(SpO2)to decrease to 92.0%under different artificial ventilation after tracheal intubation,the time for SpO2 to recover to 96.0%after resumption of ventilation,and the occurrence of adverse reactions.Results Compared with Group B,at time point T1,Group A showed a decrease in PCO2 and an increase in PaO2,with statistically significant differences(all P<0.05);Compared with T0,at time points T1 and T2,PaO2/FiO2 and PCO2 in the two groups were increased,while a/APO2 decreased(all P<0.05).At T1 time point,Pplat and Ppeak in Group A were lower than those in Group B,while Cdyn was higher than that in Group B,with statistical significance(P<0.05);Compared with T1 time point,at T2 and T3 time point,Pplat and Ppeak in Group A increased,while Cdyn decreased,with statistically significant differences(all P<0.05);Compared with T1,Ppeak increased in B groups at T2 time point(P<0.05),while Pplat and Ppeak increased in T3 time point,and Cdyn decreased in B group,with statistical significance(all P<0.05).Compared with Group B,Group A had a longer time for SpO2 to decrease to 92.0%and a shorter time for SpO2 to recover to 96.0%(P<0.01).Conclusion The combination of pre positioned nasopharyngeal airway and high head pre inhalation of oxygen can effectively improve acute respiratory obstruction during induction of general anesthesia insertion in morbid obesity patients,and extend the duration of no ventilation.

OBJECTIVE: Exploring the effectiveness of using EEG linear and nonlinear features for accessing mental workload in different tasks. METHODS: Working memory tasks with different information types and various mental loads were designed based on N-Back paradigm. EEG signals from 18 normal adults were acquired when tasks were being performed. Linear and nonlinear features of EEGs were then extracted. Indices that can effectively reflect mental workload levels were selected by using multivariate analysis of variance statistical approach. RESULTS: With the increment of task load, power of frontal Theta, Theta/Alpha ratio, and sample entropies (scales>10) in parietal regions increased significantly first and decreased slightly then, while the power of central-parietal Alpha decreased significantly first and increased slightly then. No difference in power of frontal Theta, central-parietal Alpha, and sample entropies (scales>10) of parietal regions were found between verbal and object tasks, as well as between two spatial tasks. No difference of frontal Theta/Alpha ratio was found in all the four tasks. CONCLUSIONS The results can provide evidence for the mental workload evaluation in tasks with different information types.
Electroencephalography ; Memory, Short-Term ; Workload

The complexity of oral ulcerations poses considerable diagnostic and therapeutic challenges to oral specialists. The expert consensus was conducted to summarize the diagnostic work-up for difficult and complicated oral ulcers, based on factors such as detailed clinical medical history inquiry, histopathological examination, and ulceration-related systemic diseases screening. Not only it can provide a standardized procedure of oral ulceration, but also it can improve the diagnostic efficiency, in order to avoid misdiagnosis and missed diagnosis.
Consensus ; Humans ; Oral Ulcer/therapy*

Objective: To observe the clinical effect of thumbtack needles combined with pediatric Tuina (Chinese therapeutic massage) for constipation in children caused by liver depression and Qi stagnation.Methods: A total of 60 children with constipation caused by liver depression and Qi stagnation were randomly divided into a combined group and a Tuina group, with 30 cases in each group. The cases in the Tuina group were treated with pediatric Tuina, while those in the combined group were treated with additional thumbtack needle therapy. We observed the clinical efficacy and the change in the number of spontaneous bowel movements per week before and after treatment. Results: After treatment, the cure rate and the total effective rate in the combined group were higher than in the Tuina group, showing statistical significance (P<0.05). Compared with the same group before treatment, the number of spontaneous bowel movements per week in both groups increased after treatment (P<0.05). With the progression of treatment, the number of spontaneous bowel movements per week increased in both groups, and the number in the combined group was more than that in the Tuina group, showing statistical significance (P<0.01). Conclusion: Thumbtack needles combined with pediatric Tuina is more effective than pediatric Tuina alone in the treatment of constipation in children caused by liver depression and Qi stagnation.

OBJECTIVETo investigate changes in clinicopathological features and survival of patients with gastrectomy at a single institution in China.

METHODSFrom January 1990 to December 2009, clinicopathological data of 2518 cases of gastric cancer patients who underwent surgical resection in the Sun Yat-sen University Cancer Center were analyzed retrospectively. The overall survival rate was determined using Kaplan-Meier method and log-rank test was used to determine significance. The prognosis was analyzed using univariate analysis and multivariate analysis by Cox proportional hazards model. Clinical features, pathological findings and survival differences were compared in this cohort between two consecutive periods(1990-1999 and 2000-2009).

RESULTSThe 5-year survival rates for the whole cohort and those undergoing radical resection was 48.1% and 53.7%, respectively. In the first period, the 5-year survival rate for the whole cohort and for patients undergoing radical resection was 40.1% and 45.7%. In the second period, the 5-year survival rates for whole cohort and for patients undergoing radical resection was 51.5% and 57.1%, respectively. For those who underwent radical resection, the mean number of lymph node dissection was significantly higher in the recent period (20.1±8.3 vs. 9.5±6.0, P<0.01). On multivariate analysis by means of the Cox proportional hazard model, age, location, tumor size, histological type, radical resection, lymphatic/venous invasion, depth of invasion, nodal status, number of retrieved lymph nodes, and treatment period were independent factors (P<0.05). The constitution, number of retrieved lymph nodes, and survival rate were all improved between the two intervals (P<0.05).

CONCLUSIONThe overall survival rate has gradually increased in gastric cancer patients over the past 20 years.

Gastrectomy ; Humans ; Lymph Node Excision ; Lymph Nodes ; Lymphatic Metastasis ; Multivariate Analysis ; Neoplasm Staging ; Prognosis ; Proportional Hazards Models ; Retrospective Studies ; Stomach Neoplasms ; pathology ; surgery ; Survival Rate

Objective To study the differentiation of bone marrow mesenchymal stem cells in artery tissue under different calcification environments.Methods We made a vascular calcification model using warfarin,vitamin K1 and vitamin D3.After the model was successfully made,we took artery tissue of normal SD rat arteries and calcified arteries co-cultured with MSC,which were divided into three groups.The normal group included normal artery tissue with MSC; calcified inducers group included calcified inducers (dexamethasone with β-glycerophosphate and ascorbic acid),normal arterial tissue and MSC; calcification group included calcified artery tissue and MSC.Each group was cultured for 3 weeks.On the 10th day of the experiment,osteoprotegerin (OPG) protein secretion was detected by ELISA.After three weeks,changes of cell morphology were observed using inverted microscope,and total protein content and alkaline phosphatase (ALP) activity were detected by ELISA.In additional,the Ror2 (receptor tyrosine kinase-like orphan receptor 2) mRNA expression was detected by using RT-PCR method.Results MSC in calcification group spontaneously proliferated and differentiated to osteoblast-like cells.Compared with normal group,calcification group showed that the total protein content,ALP activity of bone metabolism markers,OPG were significantly elevated,while Ror2 mRNA expression was significantly decreased.MSCs in calcified inducers group did not differentiate to osteoblast-like cells,and the total protein content and OPG were increased,while ALP activity had no significant difference as compared with the normal group.However,Ror2 mRNA expression was lower in calcified inducers group than in normal group,while was higher than that in calcification group.Conclusions MSCs proliferate into bone-like differentiation in vascular calcification environment and aggravate the vascular calcification.And in normal vascular with calcified inducers environment,MSCs proliferate into smooth muscle cell differentiation and rehabilitate the vascular calcification.These phenomenons may be related to the Ror2 expression in artery.

Objective To observe the contents of hypersensitive C-reactive protein (hs-CRP) and homocysteine before and after cluster needling at scalp acupoints in patients with acute cerebral infarction, and to discuss its significance in clinic. Method Sixty patients with acute cerebral infarction were randomized into a treatment group and a control group, 30 in each group. The control group was intervened by regular medication, while the treatment group was intervened by cluster needling at scalp acupoints in addition to the treatment given to the control group. The contents of serum hs-CRP and homocysteine were observed before and after intervention, to objectively evaluate the cluster needling at scalp acupoints in patients with acute cerebral infarction. Result The contents of serum hs-CRP and homocysteine were significantly changed after intervention in both groups (P＜0.05); there were significant differences in comparing the contents of serum hs-CRP and homocysteine between the two groups after intervention (P＜0.01). Conclusion Cluster needling at scalp acupoints can decline the contents of hs-CRP and homocysteine in patients with acute cerebral infarction.

Objective To investigate the effect of nerve growth factor (NGF) on recuperate of optic nerve after contusion by clamping in adult rabbits. Methods Sixteen adult rabbits were randomly divided into NGF and the control group with 8 rabbits in each group. After the optic nerve of the right eyes was clamped,tissue engineering nerve containing (0.06 ml) NGF(concentration: 5?10~(-4) g/L, NGF group) and 0.06 ml of PBS (control group) was immediately transplanted into the injured eyes respectively, and 0.02 ml NGF(concentration: 5?10~(-4) g/L, NGF group)and 0.02 ml of PBS (control group) were injected into the vitreous of right eyes respectively. Flash visual evoked potential (FVEP) test was performed on the eyes 1 day, 2 weeks and 8 weeks after the injury. The number of retinal ganglion cells (RGCs) and changes of optic nerves were observed by light microscopy and electron microscopy at the 8th week after contusion,and a computer-image-analysis system was used to count the optic nerve axons. Results The ratio of amplitude of FVEP of the injured and healthy eyes was 0.765?0.150 in NGF group and 0.494?0.108 in the control at the 2th week after injury with a significant difference between the two groups (P