BACKGROUND:Apoptosis plays an important role in secondary brain injury.Therefore,to explore the pathophysiological mechanism of promoting nerve cell survival after traumatic brain injury provides a new direction and theoretical basis for the prevention and treatment of traumatic brain injury. OBJECTIVE:To explore the expression changes of Lnx1 molecule in mammalian cortical neurons after brain injury and the possible mechanism involved in secondary brain injury. METHODS:Eighty adult SD rats were divided into 20 male and 20 female mice in sham operation group and 20 male and 20 female mice in traumatic brain injury group.The traumatic brain injury rat model was established by heavy falling method.At 6,12,24,48,and 72 hours after brain injury,the expression of related molecules in damaged cortical neurons was analyzed by RT-qPCR,western blot assay,and immunofluorescence staining. RESULTS AND CONCLUSION:(1)The brain tissue of traumatic brain injury group was bleeding and obvious tissue injury could be observed.Water content of brain tissue increased after traumatic brain injury.(2)Compared with the sham operation group,the expression of Lnx1 in cortical neurons after traumatic brain injury increased significantly at 24 hours after injury.(3)After traumatic brain injury,the expression of PBK and BCR protein decreased,and the pro-survival factor ctgf increased.(4)These findings suggest that after traumatic brain injury,the expression of Lnx1 is up-regulated in neurons,which may be due to the decrease of the expression of its target molecules PBK and BCR,and further promote the expression of living factor ctgf,which has a protective effect on the damaged neurons.

Objective: To investigate the current status and trends of depressive symptoms among middle school and college students in Hunan Province, and to explore the primary related factors of depressive symptoms, so as to provide a scientific basis for strengthening mental health among students. Methods: A total of 279 382 students in Hunan Province were selected through a stratified cluster random sampling method from 2021 to 2023. National Survey Questionnaire on Common Diseases and Health Influencing Factors among Students was adopted for the survey, and the Center for Epidemiological Studies Depression Scale was used to assess their depressive symptoms. The χ 2 test and trend χ 2 test were used to analyze depressive symptoms prevalence and trends, and multivariable Logistic regression was used to analyze the related factors of depressive symptoms. Results: The prevalence of depressive symptoms among students in Hunan Province from 2021 to 2023 were 19.66%, 20.17% and 21.47%, respectively, showing an upward trend ( χ 2 trend =9.07, P <0.01). In addition, the results of the multivariable Logistic regression analysis showed that students with healthy diet ( OR=0.43, 95%CI =0.40-0.45), adequate sleep ( OR=0.88, 95%CI =0.86-0.90), and acceptable screen time ( OR=0.61, 95%CI =0.60-0.62) had lower risks in depressive symptoms detection, while students with smoking ( OR= 1.95, 95%CI =1.88-2.02), secondhand smoke exposure ( OR=1.33, 95%CI =1.30-1.36) and Internet addiction ( OR= 4.19 , 95%CI =4.05-4.34) had higher risks in depressive symptoms detection, with differences in the degree of association among different genders, educational stages and urban rural groups ( OR=0.40-6.04, Z =-12.69-11.98) ( P <0.05). Conclusions There is an increasing trend of depressive symptoms among middle school and college students in Hunan Province from 2021 to 2023.Targeted depression prevention measures should be taken for students with different demographic characteristics to promote their mental health.

ObjectiveThe U6 promoter is an essential element for driving sgRNA expression in the clustered regularly interspaced short palindromic repeat sequences/CRISPR-associated protein 9（CRISPR/Cas9）gene editing system in dicotyledonous plants. Endogenous U6 promoters typically exhibit higher transcriptional activity， which can significantly improve gene editing efficiency. This study aims to identify endogenous U6 promoters in Artemisia annua to optimize its CRISPR/Cas9 gene editing system， which holds significant importance for its molecular breeding. MethodsOn the basis of the highly conserved U6 snRNA sequences in Arabidopsis thaliana， endogenous U6 promoters were screened in the A. annua genome. Expression vectors were constructed with candidate AaU6 promoter driving the firefly luciferase （LUC） reporter gene， and then transiently transformed into Nicotiana benthamiana. Transcriptional activities of the promoters were measured and compared by in vivo imaging and the Dual Luciferase Reporter assay. ResultsEight endogenous U6 promoters were successfully cloned from A. annua. Sequences alignment revealed that all these promoters contained the two conserved cis-acting elements， upstream sequence element （USE） and TATA-box， which affected their transcriptional activity. Dual-luciferase activity assays indicated that the transcriptional activities of AaU6-3， AaU6-1， and AaU6-5 were significantly higher than that of the Arabidopsis AtU6-26 promoter， with AaU6-3 exhibiting the highest activity. ConclusionThis study identified three endogenous AaU6 promoters with high transcriptional activity in A. annua， providing key functional elements for establishing an efficient gene editing system in A. annua. These findings will contribute to advancing precision molecular breeding and high-quality germplasm innovation in A. annua.

Objective To explore the research progress, research hotspot and development trend of tigecycline resistance based on the quantitative analysis and visualization function of CiteSpace. Methods The data were collected from 4,263 Chinese and English articles on tigecycline resistance in CNKI, Wanfang, VIP and Web of Science (WOS) databases from 2012 to 2022. CiteSpace 5.8.R3 software was used to analyze the cooperative network of authors, the cooperative network of countries and institutions, the total citation times of journals, and keywords included in the literature, to reveal the hotspots and trends of tigecycline resistance research. Results The number of articles published in English literature was higher than that in Chinese literature. China had the largest number of published documents, showing a significant international academic influence in this research field. Countries all over the world were concerned about the resistance of tigecycline, but Chinese literatures focused more on the clinical infection and prevention of tigecycline resistance, while English literatures placed special emphasis on the research about the drug resistance mechanism of tigecycline. Conclusion The research direction at home and abroad is basically the same, but the research focus has gradually shifted from the clinical treatment and monitoring of tigecycline to the molecular level of drug resistance mechanism.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, which is manifested by symptoms such as difficulties in social interaction and communication, stereotypical repetitive behaviors, and narrow areas of interests.At present, the intervention methods for ASD mainly include behavioral intervention, pharmacological intervention, physical intervention, exercise intervention, complementary and alternative medicine intervention.With the progress of science and technology and in-depth research, the intervention methods of ASD will develop in the direction of personalized intervention, deep learning technology, gene therapy and neurofeedback technology.These new intervention methods would hopefully improve the treatment effect and the quality of life of patients.

Objective:The emergence of polymyxin-resistant Klebsiella pneumoniae(KPN)in clinical settings necessitates an analysis of its antibiotic resistance characteristics,epidemiological features,and risk factors for its development.This study aims to provide insights for the prevention and control of polymyxin-resistant KPN infections. Methods:Thirty clinical isolates of polymyxin-resistant KPN were collected from the Third Xiangya Hospital of Central South University.Their antibiotic resistance profiles were analyzed.The presence of carbapenemase KPC,OXA-48,VIM,IMP,and NDM was detected using colloidal gold immunochromatography.Hypervirulent KPN was initially screened using the string test.Biofilm formation capacity was assessed using crystal violet staining.Combination drug susceptibility tests(polymyxin B with meropenem,tigecycline,cefoperazone/sulbactam)were conducted using the checkerboard method.Polymyxin-related resistance genes were detected by PCR.Multi-locus sequence typing(MLST)was performed for genotyping and phylogenetic tree construction.The study also involved collecting data from carbapenem-resistant(CR)-KPN polymyxin-resistant strains(23 strains,experimental group)and CR-KPN polymyxin-sensitive strains(57 strains,control group)to analyze potential risk factors for polymyxin-resistant KPN infection through univariate analysis and multivariate Logistic regression.The induction of resistance by continuous exposure to polymyxin B and colistin E was also tested. Results:Among the 30 polymyxin-resistant KPN isolates,28 were CR-KPN,all producing KPC enzyme.Four isolates were positive in the string test.Most isolates showed strong biofilm formation capabilities.Combination therapy showed additive or synergistic effects.All isolates carried the pmrA and phoP genes,while no mcr-1 or mcr-2 genes were detected.MLST results indicated that ST11 was the predominant type.The phylogenetic tree suggested that polymyxin-resistant KPN had not caused a hospital outbreak in the institution.The use of two or more different classes of antibiotics and the use of polymyxin were identified as independent risk factors for the development of polymyxin-resistant strains.Continuous use of polymyxin induced drug resistance. Conclusion:Polymyxin-resistant KPN is resistant to nearly all commonly used antibiotics,making polymyxin-based combination therapy a viable option.No plasmid-mediated polymyxin-resistant KPN has been isolated in the hospital.Polymyxin can induce resistance in KPN,highlighting the need for rational antibiotic use in clinical settings to delay the emergence of resistance.

Objective To observe the feasibility and safety of CT-guided fine-needle assisted localization for puncturing difficult lung or liver lesions.Methods Data of 30 patients with single difficult lung or liver lesion,i.e.lesion located at difficult part for puncturing or deep lesion with diameter of 0.5-2.0 cm who underwent CT-guided 22G needle assisted localization before puncturing were retrospectively analyzed.The success rate of fine-needle assisted localization,the success rate of the first-time puncturing and the occurrence of complications were recorded.Results Among 30 difficult lesions,there were 27 lung lesions and 3 hepatic lesions,with a mean diameter of(1.0±0.4)cm.Assisted localization of difficult lesions were successfully performed with 22G needle under CT guidance at the edge of lesion,1 cm adjacent to lesion or at the puncture path,with success rate of fine-needle assisted localization of 100%,and no obvious complication happened.The followed operations included preoperative localization of 14 lung nodules,biopsy of 10 lung nodules and 3 liver nodules,as well as microwave ablation of 3 liver nodules,with the success rate of the first-time puncturing of 100%.Mild pneumothorax was observed in 3 cases(3/27,11.11%)of difficult lung lesions after biopy.No other obvious complication occurred.Conclusion CT-guided fine-needle assisted localization for percutaneous puncturing difficult lung or liver lesions was feasible and safe.

Despite significant achievements of deep learning in medical image segmentation,there are challenges for brain tumor segmentation using deep learning,such as insufficient receptive field,excessive redundant information,and information loss.To address these issues,a novel brain tumor segmentation network model(EAU-Net)is proposed based on encoder-decoder structure.EAU-Net incorporates an effective receptive field expansion block and an attention fusion module to minimize the adverse effects caused by insufficient receptive field and excessive redundant information which often occurred in the current brain tumor segmentation network.Additionally,a bottleneck resampling module based on inverted residual structure is introduced to effectively avoid information loss during upsampling and downsampling,while deep convolutions are used to reduce computational complexity.Experimental results on the BraTS2020 dataset reveal that EAU-Net achieves the highest segmentation accuracy,demonstrating its feasibility and effectiveness for brain tumor segmentation.

Phenylalanine ammonia-lyase (PAL) is the key entry enzyme of plant phenylpropanoid pathway. It plays an important role in the biosynthesis of podophyllotoxin, an anti-tumor lignan that is currently produced from its main natural source Sinopodophyllum hexandrum (Royle) Ying. In this study, we cloned the gene ShPAL encoding phenylalanine ammonia-lyase by RT-PCR from the root of S. hexandrum ecotype inhabited in the Aba' district, Sichuan, based on its public SRA transcriptome data-package. Bioinformatics analyses showed that the ShPAL-encoded protein is composed of 711 amino acids, contains the conserved domains of PAL, and has the signature motif within the active center of aromatic ammonia-lyases. Moreover, ShPAL protein was predicted to have a secondary structure mainly composed of α-helix and random coil, a typical 'seahorse' shape monomer tertiary structure, and a homologous tetramer three-dimensional structure by Swiss-Modelling. The phylogenetic lineage analysis indicated ShPAL was of the highest sequence identity and the shortest evolutionary distance with the PAL of Epimedium sagittatum from the same Berberidaceae family. Subcellular localization experiments showed that ShPAL protein was mainly distributed in the cytoplasm, despite of a minority on the endoplasmic reticulum membrane. Furthermore, ShPAL protein was recombinantly expressed in Escherichia coli and purified by histidine-tag affinity chromatography. Its enzymatic activity was determined up to 20.91 U/mg, with the optimum temperature of 41 ℃ and pH of 9.0. In contrast, the enzyme activity of its F130H mutant decreased by about 23.6%, yet with the same trends of change with temperature and pH, confirming that phenylalanine at this position does affect the substrate specificity of PAL. Both the wild type and the mutant have relatively poor thermostability, but good pH-stability. These results may help to further investigate the regulatory role of PAL in the process of podophyllotoxin biosynthesis and advance the heterologous synthesis of podophyllotoxin to protect the germplasm resource of S. hexandrum. They also demonstrate that ShPAL has a potential application in biochemical industry and biomedicine.
Phenylalanine Ammonia-Lyase/metabolism* ; Podophyllotoxin ; Phylogeny ; Cloning, Molecular

ObjectiveTo summarize the modeling methods, test indicators, and evaluation methods of the animal models of urticaria and provide a basis for the subsequent research on urticaria models. MethodWith the keywords of "urticaria" and "animal model" and the time interval from inception to July 13, 2022, relevant articles were retrieved from CNKI, Wanfang Data, VIP, CBM, Web of Science, Embase, and PubMed. Two evaluators independently screened the articles and extracted the publishing time, sources, animal conditions, modeling methods, modeling time, and test indicators from the articles meeting the inclusion criteria to establish a data library for quantitative statistics and analysis. ResultA total of 116 articles were included, involving 129 animal experiments (102 in Chinese and 27 in English) of urticaria. In the last three years, the studies about the animal models of urticaria presented an obvious upward trend, and the articles were dominated by dissertations. KM mice and SD rats of both females and males were mainly used for the modeling of urticaria, and the models were mainly established by passive sensitization of skin for 14-16 days. The models were mainly evaluated based on apparent indicators such as blue-stained lesion area and ear swelling, supplemented by the pathological indicators of the skin and serum. ConclusionAlthough the experimental studies of urticaria are increasing, the modeling methods lack unified modeling standards and have low coincidence with clinical symptoms. Therefore, this paper analyzed the modeling elements and evaluation criteria of urticaria animal models, and proposed that both male and female KM mice (6-8 weeks old) or SD rats (8-10 weeks old) of SPF grade should be preferentially selected for modeling. Active and passive sensitization can be combined for the modeling, and the specific modeling elements such as modeling time and sensitization times need to be further explored. The model evaluation should include four aspects of behavior, appearance, pathology, and immunity.