Objective To explore the value of dynamic nomogram constructed by multi spiral computed tomography(MSCT)features combined with inflammatory indicators in predicting the status of microvascular invasion(MVI)of hepatocellular carcinoma(HCC)before surgery.Methods The clinical and imaging data of 137 patients with postoperative pathologically confirmed HCC were analyzed retrospectively.According to the status of the MVI,they were divided into positive group(44 cases)and negative group(93 cases).Multivariate logistic regression analysis was used to screen independent risk factors for predicting the MVI status of HCC patients,and a joint prediction model was constructed,which was displayed in the form of a dynamic nomogram.The receiver operating characteristic(ROC)curve,calibration curve and Hosmer-Lemeshow test were used to evaluate the diagnostic efficiency,calibration and goodness of fit of the model,Akaike information criterion(AIC)and Bayesian information criterion(BIC)were used for comparison between the models,and a 5-fold cross-validation and decision curve analysis(DCA)were also used to evaluate the stability and clinical applicability of the model.Results Multivariate logistic regression analysis showed that necrosis and delayed-phase enhancement(DEd),and alkaline phosphatase to lymphocyte ratio(ALR)were independent risk factors for predicting MVI status in HCC patients.The area under the curve(AUC)of the dynamic nomogram was 0.721,with the sensitivity of 0.705 and the specificity of 0.656.The AIC and BIC values were 152.372 and 158.212,respectively.The calibration curve and the Hosmer-Lemeshow test showed that the model had a high degree of calibration and goodness of fit(χ2=2.372,P=0.967),the average AUC of the 5-fold cross-validation was 0.787,and the DCA showed that the nomogram model had a good clinical applicability.Conclusion The dynamic nomogram model constructed by MSCT features combined with inflammatory indicators is feasible to predict the MVI status of HCC patients before surgery,and the dynamic nomogram can directly generate the prediction results of different individuals.

BACKGROUND:The research of dental stem cells in the fields of regenerative medicine and tissue engineering has been deepening,bringing hope for the repair of tooth-related tissues and the treatment of systemic diseases.However,there is a lack of systematic research and analysis on the biological characteristics of dental stem cells in different age groups. OBJECTIVE:To explore the biological characteristics of the human deciduous tooth and permanent tooth pulp stem cells cultured in umbilical cord blood platelet lysate to provide a reliable basis for human platelet lysates to replace fetal bovine serum. METHODS:The pulp tissues of deciduous teeth,juvenile permanent teeth and adult permanent teeth were taken out and cultured in DMEM/F-12 medium supplemented with 10%fetal bovine serum or different concentrations(5%,10%and 15%)of human platelet lysates.Cell proliferation in the four groups was detected by cytometry.The optimal concentration of human platelet lysates was selected for subsequent experiments.Under the optimal concentration of human platelet lysates,human deciduous tooth and juvenile and adult permanent tooth pulp stem cells were cultured in vitro.The cell growth status was observed under the microscope.The specific antigen on the cell surface was detected by flow cytometry.The cell proliferation ability was tested by the cell counting method and CCK-8 assay.The cell differentiation ability in vitro was observed by a three-line differentiation assay. RESULTS AND CONCLUSION:(1)The cell proliferation rate of the 10%human platelet lysate group was the highest.(2)In all three groups,fusiform fibrous cells grew and expanded from around the tissue block.There was no significant difference between deciduous teeth and juvenile permanent tooth cells,but the adult permanent tooth cells were larger than the deciduous and juvenile permanent tooth cells of the same generation.(3)The results of flow cytometry showed that deciduous teeth,juvenile permanent teeth and adult permanent teeth conformed to the phenotypic characteristics of mesenchymal stem cells.(4)The proliferative capacity of adult permanent dental pulp stem cells was significantly lower than those of deciduous teeth and juvenile permanent dental pulp stem cells(P<0.01).(5)mRNA expressions of osteoblast-related genes alkaline phosphatase and bone morphogenetic protein 2,lipoprotein lipase and peroxisome proliferator-activated receptor γ2,mRNA expressions of chondroblast related gene type II collagen α1 and cartilage oligomeric matrix protein in adult pulp stem cells of permanent teeth were significantly lower than those of deciduous teeth and juvenile permanent teeth pulp stem cells(P<0.01).(6)Compared with adult dental pulp stem cells,human deciduous teeth and juvenile permanent teeth dental pulp stem cells have the stronger proliferative capacity and multidirectional differentiation potential,and are more suitable for clinical research and disease treatment.

Objective To establish a method for quantitative analysis of tiny amounts of tritium in hydrogen below the detection limit of isotope ratio mass spectrometer. Methods Hydrogen was oxidized to produce water in a self-developed catalytic oxidation device filled with platinum hydrophobic catalyst. The effects of different experimental conditions on hydrogen conversion rate were investigated. The tritium concentration in the synthetic water was measured using a liquid scintillation counter. The tritium concentration in hydrogen was calculated according to the measurement of the synthetic water. Results When the flow rate of hydrogen was fixed, the conversion rate of hydrogen increased with the increase of the reaction temperature but increased and then decreased with the increase of the flow rate of oxygen. Hydrogen could be completely converted under optimal experimental conditions. The hydrogen samples with volumetric tritium concentrations in the range of 1 × 10⁻⁷ to 2 × 10⁻¹⁴ were converted to water at the reaction temperature of 110 ℃ and hydrogen/oxygen flow rate of 100 mL/min. The resulting water was measured using a liquid scintillation counter. The measurement accuracy was better than 2%. Conclusion This method can be used to measure hydrogen samples with tiny amounts of tritium below the detection limit of isotope ratio mass spectrometer. Our results provide data support for the calculation of the separation capacity of cryogenic distillation process.

Neck dissection(ND)is one of the main treatment methods for oral and maxillofacial malignancies.Although ND type is in con-stant improvement,but intraoperative peal-pull-push injury of the accessory nerve,muscle,muscle membrane,fascia and ligament induced shoulder syndrome(SS)is still a common postoperative complication,combined with the influence of radiochemotherapy,not only can cause pain,stiffness,numbness,limited dysfunction of shoulder neck and arm,but also may have serious impact on patient's life quality and phys-ical and mental health.At present,there is still a lack of a systematic evaluation and rehabilitation management program for postoperative SS of oral and maxillofacial malignant tumors.Based on the previous clinical practice and the current available evidence,refer to the relevant lit-erature at home and abroad,the experts in the field of maxillofacial tumor surgery and rehabilitation were invited to discuss,modify and reach a consenusus on the etiology,assessment diagnosis,differential diagnosis,rehabilitation strategy and prevention of SS,in order to provide clinical reference.

Objective:We examined the levels of Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)signaling in head and neck squamous cell carcinoma(HNSCC)and their influence on chemotherapy sensitization.Methods:Sixty patients with HNSCC who were treated at Tianjin Medical University Cancer Institute&Hospital,between January 2018 and December 2022,were included in the study.Levels of expressed JAK2,p-STAT3Y705,c-Myc,and Ki-67 in HNSCC tissues were evaluated using immunohistochemical staining,and correlation analysis was performed.The viability of UM-SCC1 cells treated with fedratinib,a JAK2 inhibitor,combined with cisplatin(DDP)and paclitaxel(PTX)was determined using the CCK8 assay.Western blot was performed to detect p-STAT3Y705 expression in tumor tissues and HNSCC cell lines.SCC15 and UM-SCC1 cell lines stably transfected with JAK2 or STAT3 vectors were constructed and verified.Cell activity and cell proliferation capacity were measured to evaluate the detrimental impact of STAT3 overexpression on chemotherapy with fedratinib using Western blot,CCK8,and plate cloning assays.Results:JAK2 expression in HNSCC positively correlated with p-STAT3Y705(r=0.43,P<0.000 1)and c-Myc(r=0.48,P<0.01)expression.High p-STAT3Y705 expression positively correlated with AJCC stage(P<0.000 1)and Ki-67 expression(P<0.05).High STAT3 and p-STAT3 levels were associated with poor prognosis in patients with HNSCC.In vitro,the JAK2 inhibitor fedratinib inhibited HNSCC cell proliferation and enhanced tumor cell sensitivity to DDP and PTX.JAK2 activation promotes STAT3 phosphorylation,and STAT3 overexpression reverses the effects of fedratinib on HNSCC sensitivity to chemotherapy.Conclusions:JAK2/STAT3 signaling is elev-ated in patients with HNSCC.Targeting the JAK2/STAT3 pathway is a potential method for increasing the sensitivity of HNSCC to chemotherapy.

Traumatic supraorbital fissure syndrome (TSOFS) is a symptom complex caused by nerve entrapment in the supraorbital fissure after skull base trauma. If the compressed cranial nerve in the supraorbital fissure is not decompressed surgically, ptosis, diplopia and eye movement disorder may exist for a long time and seriously affect the patients′ quality of life. Since its overall incidence is not high, it is not familiarized with the majority of neurosurgeons and some TSOFS may be complicated with skull base vascular injury. If the supraorbital fissure surgery is performed without treatment of vascular injury, it may cause massive hemorrhage, and disability and even life-threatening in severe cases. At present, there is no consensus or guideline on the diagnosis and treatment of TSOFS that can be referred to both domestically and internationally. To improve the understanding of TSOFS among clinical physicians and establish standardized diagnosis and treatment plans, the Skull Base Trauma Group of the Neurorepair Professional Committee of the Chinese Medical Doctor Association, Neurotrauma Group of the Neurosurgery Branch of the Chinese Medical Association, Neurotrauma Group of the Traumatology Branch of the Chinese Medical Association, and Editorial Committee of Chinese Journal of Trauma organized relevant experts to formulate Chinese expert consensus on the diagnosis and treatment of traumatic supraorbital fissure syndrome ( version 2024) based on evidence of evidence-based medicine and clinical experience of diagnosis and treatment. This consensus puts forward 12 recommendations on the diagnosis, classification, treatment, efficacy evaluation and follow-up of TSOFS, aiming to provide references for neurosurgeons from hospitals of all levels to standardize the diagnosis and treatment of TSOFS.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective To evaluate the process risk of the implementation of prevention and control measures for surgical site infection(SSI)after colorectal surgery,and explore the application effect of failure mode and effects analysis(FMEA)based on action priority.Methods FMEA based on action priority was adopted to evaluate the whole process of the implementation of prevention and control measures for SSI after colorectal surgery.Prioritiza-tion ranking was conducted according to whether optimized measures were taken.Standard-reaching rate of comp-liance to SSI prevention and control measures as well as SSI incidence before and after the implementation of FMEA were compared.Results After evaluation,there were 7 high-priority and 22 medium-priority prevention and control measures for SSI.The control of medium-priority measures was strengthened,with a focus on developing further preventive and detectable measures for high-priority measures.The re-evaluation results after improvement showed that 7 high-priority measures have been downgraded to medium priority,and 16 medium-priority measures have been downgraded to low priority.Standard-reaching rate of compliance to SSI prevention and control measures in-creased from 77.15％(2 566/3 326)to 92.47％(3 096/3 348),and SSI incidence decreased from 6.04％(58/960)to 2.54％(60/2 364).Conclusion Application of FMEA based on action priority can effectively evaluate the risk of prevention and control process of SSI after colorectal surgery,and adopting preventive risk control measures accord-ing to the current situation can reduce the incidence of SSI after colorectal surgery.

Objective To understand the change in distribution and antimicrobial resistance of bacteria isolated from blood specimens of Hunan Province,and provide for the initial diagnosis and treatment of clinical bloodstream infection(BSI).Methods Data reported from member units of Hunan Province Antimicrobial Resistance Survei-llance System from 2012 to 2021 were collected.Bacterial antimicrobial resistance surveillance method was imple-mented according to the technical scheme of China Antimicrobial Resistance Surveillance System(CARSS).Bacteria from blood specimens and bacterial antimicrobial susceptibility testing results were analyzed by WHONET 5.6 soft-ware and SPSS 27.0 software.Results A total of 207 054 bacterial strains were isolated from blood specimens from member units in Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021,including 107 135(51.7％)Gram-positive bacteria and 99 919(48.3％)Gram-negative bacteria.There was no change in the top 6 pathogenic bacteria from 2012 to 2021,with Escherichia coli(n=51 537,24.9％)ranking first,followed by Staphylococcus epidermidis(n=29 115,14.1％),Staphylococcus aureus(n=17 402,8.4％),Klebsiella pneu-moniae(17 325,8.4％),Pseudomonas aeruginosa(n=4 010,1.9％)and Acinetobacter baumannii(n=3 598,1.7％).The detection rate of methicillin-resistant Staphylococcus aureus(MRSA)decreased from 30.3％in 2015 to 20.7％in 2021,while the detection rate of methicillin-resistant coagulase-negative Staphylococcus(MRCNS)showed an upward trend year by year(57.9％-66.8％).No Staphylococcus was found to be resistant to vancomy-cin,linezolid,and teicoplanin.Among Gram-negative bacteria,constituent ratios of Escherichia coli and Klebsiella pneumoniae were 43.9％-53.9％and 14.2％-19.5％,respectively,both showing an upward trend(both P＜0.001).Constituent ratios of Pseudomonas aeruginosa and Acinetobacter baumannii were 3.6％-5.1％and 3.0％-4.5％,respectively,both showing a downward trend year by year(both P＜0.001).From 2012 to 2021,resistance rates of Escherichia coli to imipenem and ertapenem were 1.0％-2.0％and 0.6％-1.1％,respectively;presenting a downward trend(P＜0.001).The resistant rates of Klebsiella pneumoniae to meropenem and ertapenem were 7.4％-13.7％and 4.8％-6.4％,respectively,presenting a downward trend(both P＜0.001).The resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannii to carbapenem antibiotics were 7.1％-15.6％and 34.7％-45.7％,respectively.The trend of resistance to carbapenem antibiotics was relatively stable,but has de-creased compared with 2012-2016.The resistance rates of Escherichia coli to the third-generation cephalosporins from 2012 to 2021 were 41.0％-65.4％,showing a downward trend year by year.Conclusion The constituent ra-tio of Gram-negative bacillus from blood specimens in Hunan Province has been increasing year by year,while the detection rate of carbapenem-resistant Gram-negative bacillus remained relatively stable in the past 5 years,and the detection rate of coagulase-negative Staphylococcus has shown a downward trend.

Objective To investigate changes in the distribution and antimicrobial resistance of bacteria isolated from cerebrospinal fluid(CSF)specimens in Hunan Province,and provide reference for correct clinical diagnosis and rational antimicrobial use.Methods Data reported by member units of Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021 were collected according to China Antimicrobial Resistance Surveillance Sys-tem(CARSS)technical scheme.Data of bacteria isolated from CSF specimens and antimicrobial susceptibility tes-ting results were analyzed with WHONET 5.6 and SPSS 20.0 software.Results A total of 11 837 bacterial strains were isolated from CSF specimens from member units of Hunan Province Antimicrobial Resistance Surveillance Sys-tem from 2012 to 2021.The top 5 strains were coagulase-negative Staphylococcus(n=6 397,54.0％),Acineto-bacter baumannii(n=764,6.5％),Staphylococcus aureus(n=606,5.1％),Enterococcus faecium(n=465,3.9％),and Escherichia coli(n=447,3.8％).The detection rates of methicillin-resistant coagulase-negative Staphyloco-ccus(MRCNS)and methicillin-resistant Staphylococcus aureus(MRSA)were 58.9％-66.3％and 34.4％-62.1％,respectively.No Staphylococcus spp.were found to be resistant to vancomycin,linezolid,and teicoplanin.The de-tection rate of Enterococcus faecium was higher than that of Enterococcus faecalis,and the resistance rates of En-terococcus f aecium to penicillin,ampicillin,high concentration streptomycin and levofloxacin were all higher than those of Enterococcus faecalis(all P=0.001).Resistance rate of Streptococcus pneumoniae to penicillin was 85.0％,at a high level.Resistance rate of Escherichia coli to ceftriaxone was＞60％,while resistance rates to enzyme inhibitors and carbapenem antibiotics were low.Resistance rate of Klebsiella pneumoniae to ceftriaxone was＞60％,to en-zyme inhibitors piperacillin/tazobactam and cefoperazone/sulbactam was＞30％,to carbapenem imipenem and me-ropenem was about 30％.Resistance rates of Acinetobacter baumannii to most tested antimicrobial agents were＞60％,to imipenem and meropenem were 59.0％-79.4％,to polymyxin B was low.Conclusion Among the bac-teria isolated from CSF specimens,coagulase-negative Staphylococcus accounts for the largest proportion,and the overall resistance of pathogenic bacteria is relatively serious.Bacterial antimicrobial resistance surveillance is very important for the effective treatment of central nerve system infection.