In recent years, the bacteriophage Φ29 (Phi29) DNA polymerase has garnered increasing attention due to its high-fidelity amplification capacity at constant temperatures. To advance the industrial application of this type of isothermal polymerases, this study mined and characterized new enzymes from the microbial metagenome based on the known Phi29 DNA polymerase sequence. The results revealed that a new enzyme, Php29 DNA polymerase, was identified in the microbial metagenome with plants as the hosts. This enzyme exhibited higher strand displacement activity, with a 59.5% similarity to bacteriophage Φ29. Experimental validation demonstrated that the enzyme had 3'→5' exonuclease activity, and its amplification products can serve as substrates for further catalytic reactions. The discovery and validation of Php29 DNA polymerase gives insights into the future industrial application of isothermal polymerases.
DNA-Directed DNA Polymerase/metabolism* ; Bacillus Phages/genetics* ; Metagenome

Objective To investigate the relationship between peripheral blood composite inflammatory in-dexes[systemic immune inflammatory index(SII),lymphocyte to monocyte ratio(LMR),eosinophil to neu-trophil ratio(ENR),neutrophil to lymphocyte ratio(NLR)]and the severity of respiratory adenovirus(AdV)infection and concurrent wheezing in children.Methods A total of 154 children with respiratory AdV infec-tion(study group)who were admitted to the hospital from June 2022 to May 2024 and 154 healthy children who underwent physical examinations(control group)were selected.Children with respiratory AdV infection were divided into mild group(86 cases)and severe group(68 cases)according to the pediatric sequential or-gan failure assessment(p-SOFA),and children were divided into wheezing group(79 cases)and non-wheezing group(75 cases)according to whether wheezing occurred in children with respiratory AdV infection.The pe-ripheral blood SII,LMR,ENR and NLR in each group were detected and compared,the correlation between peripheral blood SII,LMR,ENR,NLR and the severity of respiratory AdV infection in children was analyzed by Pearson method.The factors affecting wheezing in children with respiratory AdV infection were analyzed by univariate and multivariate Logistic regression analysis.The diagnostic value of peripheral blood composite inflammatory indexes for the severity of respiratory AdV infection and concurrent wheezing in children was e-valuated by drawing the receiver operating characteristic curve.Results The peripheral blood SII,ENR and NLR in severe group were higher than those in mild group and control group(P＜0.05),while the peripheral blood SII,ENR and NLR in mild group were higher than those in control group(P＜0.05).The peripheral blood LMR in severe group was lower than those in mild group and control group(P＜0.05),while the pe-ripheral blood LMR in mild group was lower than that in control group(P＜0.05).The p-SOFA in severe group was higher than that in mild group(P＜0.05).Peripheral blood SII,ENR and NLR in children with re-spiratory AdV infection were positively correlated with p-SOFA(r=0.512,0.439,0.507,P＜0.05),and LMR was negatively correlated with p-SOFA(r=-0.436,P＜0.05).The area under the curve(AUC)of the single detection of SII,LMR,ENR and NLR for diagnosing severe respiratory AdV infection were 0.785,0.809,0.784 and 0.834 respectively,and the AUC of combined detection was 0.916,which was larger than those of single detection(P＜0.05).SII,ENR and NLR in wheezing group were higher than those in non-wheezing group(P＜0.05),and LMR was lower than that in non-wheezing group(P＜0.05).Small airway disease,high SII,high ENR and high NLR were risk factors for wheezing in children with respiratory AdV in-fection(P＜0.05),and high LMR was a protective factor(P＜0.05).The AUC of the single detection of SII,LMR,ENR and NLR for diagnosing wheezing in children with respiratory AdV infection were 0.778,0.771,0.757 and 0.805 respectively,and the AUC of combined diagnosis was 0.884,which was larger than those of single detection(P＜0.05).Conclusion The peripheral blood SII,ENR and NLR in children with respiratory AdV infection increase,and the LMR decreases,which are closely related to the aggravation of the severity of the disease and the concurrent wheezing.The combined detection of four indexes has high value in the diagno-sis of the severity of the disease and the risk of concurrent wheezing.

On plateaus,the low-oxygen and low-pressure environment is likely to lead to cognitive impairments,negatively impacting individuals newly exposed to high altitudes.This paper reviews how high-altitude environments impair cognitive functions and explores protective strategies in terms of oxygen-enriched and pressurization technologies,neuroregulation techniques,and approaches to endogenous protection.It is recommended that future research focus on personalized cognitive protection and training,the construction of integrated protection systems based on multi-technology convergence,and the investigation of long-term effectiveness and sustainability.These efforts are expected to result in more comprehensive strategies for cognitive protection and enhancement in high-altitude operations.

ObjectiveTo analyze the scores of the second-tier assessment on theory of competency of Traditional Chinese Medicine （TCM） physicians based on cognitive diagnostic model， and to provide a reference for cognitive diagnostic studies of large-scale medical examinations. MethodsCognitive diagnostic analyses were conducted by selecting the responses of 16，310 candidates who took the theory examination of the second-tier assessment on the competency of TCM physicians in 2023. The degree of fit between the topological deterministic input noise and gate model （G-DINA model） and the examination data was examined； item parameter analysis and reliability analysis were conducted under the cognitive diagnostic framework； the candidates' mastery of cognitive attributes was comprehensively analysed at different levels. ResultsThe mean score of 16，310 candidates in this study was （189.76 ± 40.86）， and a total of 9，994 candidates passed this examination， with a pass rate of 61.28 %. The total number of questions in the examination was 300， and among the five modules， the frequency of assessment of TCM fundamentals was the highest （132 questions， 44%）， followed by TCM clinic （87 questions， 29%）， Western medicine fundamentals （60 questions， 20%）， and TCM classics （12 questions， 4%） and medical humanities （9 questions， 3%） was less. The results of the model fit index showed that the area under the curve （AUC） of the G-DINA model was 0.98， indicating that the model fit the study data excellently. The results of item parameter analysis showed that all the discriminations of the cognitive diagnostic model for the 300 test questions were greater than 0， with an average discrimination of 0.25， and the overall performance of the question discriminations was good. The results of the reliability analysis showed that the test level classification accuracy was 0.75， and the attribute level classification accuracy was 0.83 to 0.99， indicating that the G-DINA model has high attribute classification accuracy. The results of the cognitive diagnostic analyses showed that the proportion of candidates who had passed the exam was higher for the cognitive attributes of each module compared to those who had not passed the exam. ConclusionThe analysis of large-scale TCM examinations based on cognitive diagnosis can provide support for improving the quality of TCM talent education and cultivation.

Background The threshold limit values (TLVs) established and regularly updated by the American Conference of Governmental Industrial Hygienists (ACGIH) are widely adopted and referenced globally, serving as a crucial reference for China's occupational exposure limits (OELs). It is necessary to track it regularly and compare it with China's OELs. Objective To compare the OELs stipulated in Occupational exposure limits for hazardous agents in the workplace—Part 1: Chemical hazardous agents (GBZ 2.1—2019) and the ACGIH TLVs (2024) and to provide references for subsequent formulation and revision of OELs in China. Methods The OELs specified in GBZ 2.1—2019 and the TLVs issued by ACGIH were used to establish a database using Microsoft Excel 2019 software. Cross verification was conducted through matching Chemical Abstracts Service Registry Numbers (CAS Rn) and both Chinese and English names to ensure accuracy. Then, comparisons and analyses were carried out based on the type of limit values, which were matched as follows: permissible concentration-time weighted average (PC-TWA) with threshold limit value-time weighted average (TLV-TWA), permissible concentration-short term exposure limit (PC-STEL) with threshold limit value-short term exposure limit (TLV-STEL), and maximum allowable concentration (MAC) with threshold limit value-ceiling (TLV-C). Comparisons included types, quantities, and sizes of limits. Results The GBZ 2.1—2019 OELs and the ACGIH TLVs (2024) were generally consistent in terms of types and definitions, but there were differences in the number and size of the limits. In terms of the number of limits, GBZ 2.1—2019 specified 365 OELs for 358 chemical hazardous agents, while ACGIH TLVs (2024) included 316 corresponding limits. Among these, 148 (46.9%) limits were consistent, 38 (12.0%) were basically consistent, and 130 (41.1%) were inconsistent. In terms of the size of the limits, out of the 130 inconsistent limits, 51 OELs were lower than the corresponding TLVs, 67 OELs were higher than the corresponding TLVs, and 12 were under different limit types. For some chemical hazardous agents, their OELs were significantly lower or higher than their TLVs. Conclusion Some of the OELs for chemical hazardous agents specified in GBZ 2.1—2019 are significantly lower or higher than the TLVs. For these chemical hazardous factors, it is recommended to prioritize their inclusion in research projects and to complete the revisions as soon as possible based on the latest scientific evidence.

With the continuous development of medical science and the widespread use of antibiotics,the problem of bacterial resistance is increasing,especially the increasing carbapenem-resistant Enterobacteriaceae(CRE)infection,and the high mortality rate,which brings great challenges to clinical treatment.In this paper,the mechanism of drug resistance,existing antibac-terial drugs,and exploratory treatment options for CRE are reviewed,and the research progress in treating CRE infection is dis-cussed to provide more reliable evidence and a theoretical basis for clinical practice.

Objective To investigate the relationship between polymorphism of resistin(RETN)gene and metabolic associated fatty liver disease(MAFLD)in type 2 diabetes mellitus(T2DM)patients in middle and high altitude areas.Methods A total of 400 patients with T2DM in Qinghai area were recruited and divided into simple T2DM group(T2DM,n=200)and T2DM combined with MAFLD group(T2DM+ MAFLD,n=200)according to liver ultrasonography.Healthy individuals confirmed by physical examination were selected as the normal control group(NC,n=180).Plasma resistin levels were measured by ELISA.The polymorphism of RETN-420C/G and +299G/A genes were detected by PCR sequencing.Results By comparing the polymorphism of RETN-420C/G gene in each group,it was found that the frequencies of G/G genotype and G allele frequency in T2DM+MAFLD group were higher than those in NC group and T2DM group(P<0.05),while the frequencies of C/C genotype and C allele frequency were lower than those in NC group and T2DM group(P<0.05).The risk of MAFLD increased by 1.571,2.126 and 1.537 times respectively in T2DM patients with C/G,G/G genotype and G allele.Logistic regression analysis showed that G/G genotype was a risk factor for MAFLD in T2DM patients.By comparing the polymorphism of RETN+299G/A gene in each group,it was found that A allele frequency in T2DM+MAFLD group was higher than that in NC group and T2DM group,while G allele frequency was lower than that in NC group and T2DM group(P<0.05).The allele A increased the risk of MAFLD in T2DM patients by 1.432 times compared to allele G.Conclusion RETN gene-420C/G locus G/G genotype increases the risk of T2DM combined with MAFLD in middle and high altitudeareas.

As the continuation of the left ventricle,the left atrium and left ventricle interact and play an important role in the function of the whole heart.At present,there are many techniques to evaluate the atrial structure and function,but the left atrial structure is complex and the myocardium is thin,which brings some challenges to the relevant evaluation.This paper introduces the parameters,precautions and relevant clinical applications in the process of left atrial evaluation from the aspects of myocardial strain and delayed enhancement.

Objective To observe the effect of ultrasound-guided anterior quadratus lumborum block at lateral supra-arcuate ligament(QLB-LSAL)and transversus abdominis plane block(TAPB)on analgesia and recovery quality after laparoscopic partial hepatectomy(LPH).Methods Fifty-eight patients underwent elective LPH were selected and divided into the quadratus lumborum group or the transversus abdominis group randomly,with 29 patients in each group.The quadratus lumborum group received bilateral QLB-LSAL,and the transversus abdominis group received bilateral subcostal TAPB block before surgery.Both groups received 20 mL of 0.33%ropivacaine on each side.All patients used patient-controlled intravenous analgesia(PCIA)postoperatively.The numeric rating scale(NRS)scores for rest and movement were recorded at 2,4,6,12,24 and 48 hours postoperatively,as well as the Quality of Recovery-15(QoR-15)scores at 1 day preoperatively,1 and 3 days postoperatively.The perioperative anesthetic agent consumption,PCIA pressing frequency,remedial analgesia use in 48 h,postoperative nausea and vomiting(PONV)incidence and time of first out-of-bed mobilization were also recorded.Results Compared with the transversus abdominis group,the quadratus lumborum group had lower movement NRS scores at 2,4,6,12,24 and 48 hours postoperatively,and lower rest NRS scores at 2,4,6,12 and 24 hours postoperatively(P＜0.05).The quadratus lumborum group had higher QoR-15 scores at 1 and 3 days postoperatively(P＜0.05).Patients in the quadratus lumborum group had reduced perioperative remifentanil and sufentanil consumption,postoperative 48-hour rescue analgesia use,PCIA pressing frequency,PONV incidence and time of first out-of-bed mobilization(P＜0.05).Conclusion QLB-LSAL block provides superior analgesic effects and recovery quality compared to TAPB block after LPH.

ObjectiveTo investigate whether paeonol exerts a protective effect on mice with alcoholic liver injury by regulating the takeda G-protein-coupled receptor 5 （TGR5）/protein kinase A （PKA）/cAMP response binding element （CREB） signaling pathway mediated by Eubacterium. MethodC57BL/6 mice were randomly divided into five groups： normal group， model group， paeonol group （480 mg·kg^-1）， antibiotic group （Abs group）， and antibiotic + paeonol group. Lieber-DeCarli liquid was used to feed C57BL/6 mice on the second day of modeling for 10 days. The blood lipids， liver function， inflammatory factors， and oxidative stress levels in mice were measured. Hematoxylin-eosin staining （HE） and oil red O staining were used to observe the morphological changes and fat accumulation in liver tissue. 16S rDNA sequencing was used to detect the diversity of intestinal microbiota in the blank， model， and paeanol groups. Western blot was used to detect the effect of paeonol on the expression levels of protein related to the signaling pathway of atresia band protein 1 （ZO-1）， Claudin-1， and TGR5/PKA/CREB in mouse ileal tissue. ResultCompared with those in the blank group， the blood lipids， liver function， oxidative stress levels， and the expression of inflammatory factors in the model group increased （P<0.01）， and the liver fat vacuoles were obvious. The ileal mucosa was seriously damaged， and the protein contents of ZO-1， Claudin-1， and TGR5/PKA/CREB in the ileal tissue decreased significantly （P<0.01）. The intestinal microbiota changed， and the proteobacteria phylum increased significantly. The ratio of Bacteroidetes to Firmicutes decreased. The relative abundance of Dubosiella newyorkensis， Lactobacillus， Bifidobacterium， and other genera decreased， while the relative abundance of Escherichia-Shigella， Morganella， Providencia， and Proteus increased significantly. Compared with the model group， paeonol significantly reduced the blood lipids， liver function， oxidative stress levels， and expression of inflammatory factors in mice with alcohol diet-induced liver injury （P<0.05）， decreased liver fat vacuoles， improved and restored the ileal intestinal barrier， and restored the normal structure of hepatocytes and ileal cells. The intestinal microbiota disorder caused by alcohol was improved， and the relative abundance of beneficial bacteria such as Eubacterium spp. was increased. The protein expression levels of ZO-1， Claudin-1， and TGR5/PKA/CREB in ileal tissue were increased （P<0.05）. ConclusionPaeonol has a protective effect on alcoholic liver injury in mice， and the mechanism of action is achieved by regulating the Eubacterium-mediated TGR5/PKA/CREB signaling pathway to ensure anti-inflammatory effect and improve the intestinal barrier.