ObjectiveTo identify the rate， population characteristics， and vaccination history of repeat infections among previously infected people in the current epidemic based on the rate of repeat infection and population characteristics of different mutant strains at different times in Pudong New Area of Shanghai， and to provide reference for the prevention and control strategies of novel coronavirus repeat infections. MethodsA total of 9 250 investigated subjects were randomly selected from the new cases of asymptomatic infection and confirmed cases reported by Pudong New Area from March to May 2022. The investigation mainly focused on demographic characteristics， nucleic acid or antigen test results， and symptoms after infection. The repeat infection rates among different populations were compared， and logistic regression was used to analyze the impact of gender， age， and vaccination status on repeat infections. ResultsThe survey sample of 9 250 people had a response rate of 81.85%. There were 4 043 males （53.40%） and 3 528 females （46.60%）， with a median age of 34 years old （P₂₅， P₇₅： 7， 61）. The overall vaccine uptake rate was 59.44% （4 500/7 571）. In December of 2022， there were 563 cases of repeat infection， with an infection rate of 7.44%. The lowest rate of repeat infection was seen in the 3‒ year-old group （2.86%） and the highest rate in the 30‒ year-old group （12.42%）， with significant differences between different age groups. The repeated infection rate for those who had completed their vaccinations was significantly lower （6.57%） compared to those who had not （7.11%）. The age groups of 3‒ years， 70‒79 years， as well as individuals who completed full vaccination and received booster shots were protective factors against repeat infections. ConclusionThe overall rate of reinfection among the infected in Shanghai during the spring of 2022 was low in the outbreak of the Omicron variant， and the rate of reinfection in the 3‒ year-old group was significantly lower than in other age groups. Completing the full course of vaccination significantly reduces the risk of reinfection. Although the reinfection rate is high in individuals who received booster shots， it remains a mitigating factor compared to those who do not receive the vaccine. It is recommended to continue monitoring reinfections in key populations and further strengthen immunization efforts.

This study aims to investigate the effect of salvianolic acid B (Sal B), the active ingredient of Salvia miltiorrhiza, on H9C2 cardiomyocytes injured by oxygen and glucose deprivation/reperfusion (OGD/R) through regulating mitochondrial fission and fusion. The process of myocardial ischemia-reperfusion injury was simulated by establishing OGD/R model. The cell proliferation and cytotoxicity detection kit (cell counting kit-8, CCK-8) was used to detect cell viability; the kit method was used to detect intracellular reactive oxygen species (ROS), total glutathione (t-GSH), nitric oxide (NO) content, protein expression levels of mitochondrial fission and fusion, apoptosis-related detection by Western blot. Mitochondrial permeability transition pore (MPTP) detection kit and Hoechst 33342 fluorescence was used to observe the opening level of MPTP, and molecular docking technology was used to determine the molecular target of Sal B. The results showed that relative to control group, OGD/R injury reduced cell viability, increased the content of ROS, decreased the content of t-GSH and NO. Furthermore, OGD/R injury increased the protein expression levels of dynamin-related protein 1 (Drp1), mitofusions 2 (Mfn2), Bcl-2 associated X protein (Bax) and cysteinyl aspartate specific proteinase 3 (caspase 3), and decreased the protein expression levels of Mfn1, increased MPTP opening level. Compared with the OGD/R group, it was observed that Sal B had a protective effect at concentrations ranging from 6.25 to 100 μmol·L^-1. Sal B decreased the content of ROS, increased the content of t-GSH and NO, and Western blot showed that Sal B decreased the protein expression levels of Drp1, Mfn2, Bax and caspase 3, increased the protein expression level of Mfn1, and decreased the opening level of MPTP. In summary, Sal B may inhibit the opening of MPTP, reduce cell apoptosis and reduce OGD/R damage in H9C2 cells by regulating the balance of oxidation and anti-oxidation, mitochondrial fission and fusion, thereby providing a scientific basis for the use of Sal B in the treatment of myocardial ischemia reperfusion injury.

Objective To summarize the experience and practical value of living donor kidney harvesting in Bama miniature pigs with six gene modified. Methods The left kidney of Bama miniature pigs with six gene modified was obtained by living donor kidney harvesting technique. First, the ureter was occluded, and then the inferior vena cava and abdominal aorta were freed. During the harvesting process, the ureter, renal vein and renal artery were exposed and freed in sequence. The vascular forceps were used at the abdominal aorta and inferior vena cava, and the renal artery and vein were immediately perfused with 4℃ renal preservation solution, and stored in ice normal saline for subsequent transplantation. Simultaneously, the donor abdominal aorta and inferior vena cava gap were sutured. The operation time, blood loss, warm and cold ischemia time, postoperative complications and the survival of donors and recipients were recorded. Results The left kidney of the genetically modified pig was successfully harvested. Intraoperative bleeding was 5 mL, warm ischemia time was 45 s, and cold ischemia time was 2.5 h. Neither donor nor recipient pig received blood transfusion, and urinary function of the kidney transplanted into the recipient was recovered. The donor survived for more than 8 months after the left kidney was resected. Conclusions Living donor kidney harvesting is safe and reliable in genetically modified pigs. Branch blood vessels could be processed during kidney harvesting, which shortens the process of kidney repair and the time of cold ischemia. Living donor kidney harvesting contributes to subsequent survival of donors and other scientific researches.

Objective To explore the correlation between healthcare-associated infection(HAI)and partial inde-xes in the diagnosis-related groups(DRGs)of patients in thoracic surgery intensive care unit(ICU).Methods DRGs,case mix index(CMI),relative weight(RW),and HAI of patients in thoracic surgery ICU and four subspe-cialty departments(pulmonary surgery group,esophageal surgery group,mediastinum group[mainly thymic sur-gery],and trachea group)in a tertiary chest hospital in Shanghai from January to December 2022 were retrospec-tively analyzed and compared through DRGs index grouping.Results A total of 1 429 patients in the department of thoracic surgery ICU were analyzed,including 59 HAI cases,with a HAI rate of 4.13％.The incidences of HAI in pulmonary surgery group,esophageal surgery group,mediastinum group and trachea group were 3.74％(30/803),5.84％(25/428),1.27％(2/157)and 4.88％(2/41),respectively.There was no statistically significant differ-ence in the incidences of HAI among different subspecialty groups(P＞0.05).A total of 35 DRGs were involved,with CMI of 2.75,3.41,2.35 and 1.25 in pulmonary surgery group,esophageal surgery group,mediastinum group and trachea group,respectively,and RW ranged from 0.53 to 12.62.In the pulmonary surgery group,inci-dence of HAI in male patients was higher than that in female patients.Higher RW score level was associated with higher incidence of HAI.Differences were all statistically significant(all P 0.05).Among patients in the esophageal surgery group,the age of HAI group was higher than that of the non-HAI group(P＜0.05).Higher RW score level was associated with higher incidence of HAI(P＜0.05).Among patients in the mediastinum sur-gery group,the age of patients in the infected group was higher than that in the non-infected group(P＜0.05).Among the 59 HAI cases,31 were infected with MDROs.Conclusion Focusing on CMI and RW in the DRGs in-dex system,analyzing HAI from the perspectives of disease complexity and overall technical difficulties of medical services can provide reference for the precise management of HAI in the new era.

ObjectiveTo investigate the effects of Aconiti Coreani Radix and Typhonii Rhizoma on the urinary metabolites of gerbils with stroke by non-targeted metabolomics technique， and then to clarify the mechanism of the two， as well as their similarities and differences. MethodTwenty-four gerbils were randomly divided into control group（CG）， model group（MG）， Aconiti Coreani Radix group（RA） and Typhonii Rhizoma group（RT）. Except for the CG， ischemic stroke model was constructed using right unilateral ligation of gerbil carotid artery in the remaining groups. Except for the CG and MG， rats in the other groups received whole powder suspension（0.586 mg·g^-1） was administered for 14 days. The neurological deficit in each group was scored by Longa scoring on days 0， 3， 7 and 14. After the end of administration， the serum， brain tissue and urine of gerbils in each group were collected， and the rate of cerebral infarction was detected by 2，3，5-triphenyltetrazolium chloride（TTC）， and the levels of interleukin（IL）-6， tumor necrosis factor（TNF）-α， malondialdehyde（MDA）， superoxide dismutase（SOD）， glutathione（GSH）， and nitric oxide（NO） in serum and brain tissue were determined by enzyme-linked immunosorbent assay（ELISA）. The urine metabolomics of gerbils in each group was studied by ultra performance liquid chromatography-quadrupole-electrostatic field orbitrap high resolution mass spectrometry（UPLC-Q-Orbitrap-MS）， and the data were processed by multivariate statistical analysis， and differential metabolites were screened based on value of variable importance in the projection（VIP） of the first principal component>1 and t-test P<0.05. Metabolic pathway analysis of the screened differential metabolites was performed using Kyoto Encyclopedia of Genes and Genomes（KEGG） database and Metaboanalyst 5.0. ResultCompared with the CG， the neurological deficit score was significantly increased in the MG（P<0.05）， compared with the MG， the neurological deficit scores in the RA and RT were significantly reduced after 7 d and 14 d（P<0.05）. Compared with the CG， the rate of cerebral infarction was significantly increased in the MG（P<0.05）， compared with the MG， the rates of cerebral infarction in the RA and RT were significantly reduced（P<0.05）. Compared with the CG， the levels of IL-6， TNF-α， and MDA in the serum and brain tissue of gerbils from the MG were significantly increased（P<0.05）， and the levels of SOD， GSH and NO were significantly reduced（P<0.05）. Compared with the MG， Aconiti Coreani Radix and Typhonii Rhizoma could down-regulate the levels of IL-6， TNF-α and MDA， and up-regulated the levels of SOD， GSH and NO. A total of 112 endogenous differential metabolites were screened by urine metabolomics， of which 16 and 26 metabolites were called back by Aconiti Coreani Radix and Typhonii Rhizoma， and could be used as potential biomarkers for both treatments in stroke gerbils， respectively. The results of the pathway analysis showed that both Aconiti Coreani Radix and Typhonii Rhizoma had regulatory effects on arginine and proline metabolism， pyrimidine metabolism， and aminoacyl-tRNA biosynthesis. In addition， Aconiti Coreani Radix could also regulate riboflavin metabolism， Typhonii Rhizoma could also regulate purine metabolism， glycine， serine and threonine metabolism， arachidonic acid metabolism， biosynthesis of pantothenate and coenzyme A， and β-alanine metabolism. ConclusionBoth Aconiti Coreani Radix and Typhonii Rhizoma have better therapeutic effects on stroke， with Aconiti Coreani Radix having stronger effects. From the metabolomics results， the main metabolic pathways regulated by Aconiti Coreani Radix involve amino acid metabolism， oxidative stress and so on， while Typhonii Rhizoma mainly involve amino acid metabolism， lipid metabolism， energy metabolism， etc.

Objective To evaluate the pharmacokinetic characteristics and safety of single and multiple oral azvudine tablets in healthy young and elderly Chinese subjects.Methods This was a open-label and parallel-group study.The trial consisted of two groups:healthy young subjects group and healthy elderly subjects group,with 12 subjects in each group.Enrolled subjects were first given a single dose,fasting oral azvudine tablet 5 mg,after a 3-day cleansing period entered the multiple dose phase,fasting oral azvudine tablet 5 mg·d-1 for 7 days.Results After a single dose of azvudine 5 mg,Cmax and AUC0-∞ were(4.76±2.12)ng·mL-1,(6.53±2.20)ng·mL-1·h,and Tmax,t1/2 were 0.75,1.87 h in young subjects;Cmax and AUC0-∞ were(6.40±3.25)ng·mL-1,(9.50±3.70)ng·mL-1·h,and Tmax,t1/2 were 0.63,2.66 h in elderly subjects.After a multiple dose of azvudine 5 mg·d-1 for 7 d,Cmax and AUC0-∞ were(3.26±1.61)ng·mL-1,(5.38±2.19)ng·mL-1·h,and Tmax,ss,t1/2,ss were 0.88,2.13 h in young subjects;Cmax,ss and AUC0-∞,ss were(3.97±2.09)ng·mL-1,(6.71±3.26)ng·mL-1·h,and Tmax,ss,t1/2,ss were 0.75,2.56 h in elderly subjects.Elderly/young geometric mean ratios and 90％CIs were 128.37％(88.23％-186.76％),139.93％(105.42％-185.72％),140.03％(106.33％-184.41％)for azvudine Cmax,AUC0-t,AUC0-∞ after a single dose,and were 118.66％(80.83％-174.20％),118.41％(83.60％-167.69％),118.95％(84.78％-166.89％)for azvudine Cmax,AUC0-t,AUC0_∞ after a multiple dose of azvudine 5 mg·d-1 for 7 d.Conclusion After single and multiple oral administration of azvudine tablets,systemic exposure to azvudine was higher in healthy elderly subjects compared with healthy young subjects.After taking azvudine tablets,the types,severity and incidence of adverse events and adverse drug reactions in healthy elderly people were not significantly different from those in healthy young subjects.Azvudine was found to be safe and well tolerated in healthy elderly subjects.

Objective To investigate the effect of dihydromyricetin(DMY)on myocardial oxidative damage in exhaustive exercise mice.Methods C57BL/6 mice were divided into control group,model group,positive control group and low,medium and high dose experimental groups and with 10 mice in each group.Mice in control group and model group were intragastricated with distilled water;20,40 and 80 mg·kg-1 dihydromyricetin were given by gavage in low,medium and high dose experimental groups,while mice in positive control group were intragastricated with 100 mg·kg-1 Vitamin C once a day for 4 weeks.After administration,superoxide dismutase(SOD),malondialdehyde(MDA)and lactate dehydrogenase(LDH)were detected by the kit.The expression of nuclear factor E2-related factor 2(Nrf2)and heme oxygenase-1(HO-1)protein were detected by Western blot.Results SOD levels in control group,model group and low,medium,high dose experimental groups and positive control group were(57.81±6.92),(26.85±2.74),(33.68±4.52),(39.74±3.95),(48.97±4.26)and(39.22±3.54)U·mg-1;MDA were(4.72±0.36),(10.48±1.68),(8.75±0.82),(6.43±0.71),(5.11±0.48)and(6.36±0.64)nmol·mg-1;LDH were(268.71±23.94),(726.58±81.26),(621.32±47.59),(479.12±50.24),(337.91±34.99)and(486.15±50.98)U·L-1;Nrf2 protein expression were 0.75±0.06,0.19±0.02,0.30±0.04,0.47±0.05,0.63±0.06 and 0.49±0.06;the protein expression of HO-1 were 0.83±0.08,0.27±0.05,0.39±0.04,0.52±0.03,0.77±0.07 and 0.55±0.06,respectively.There were statistically significant differences between control group and model group(all P＜0.05);there were statistically significant differences in the above indexes between model group and positive control group,low dose experimental group,medium dose experimental group,high dose experimental group(all P＜0.05).Conclusion Dihydromyricetin can delay myocardial oxidative injury in exhaustive exercise mice,which may be related to Nrf2/HO-1 pathway.

Objective To establish a new animal model of filum terminale traction tethered cord syndrome to explore its pathogenesis.Methods Sixteen New Zealand white rabbits were randomly divided into the traction group and the sham group,with 8 rabbits in each group.The traction group used silk thread to establish a model of filum terminale traction tethered cord syndrome,while the sham group only cut the filum terminale without traction.After 8 weeks,the behavioral Talov score,lumbosacral MRI examination,somatosensory evoked potential detection,urodynamic index test and pathological analysis were completed.Results At the 8th week after surgery,the hindlimb injury was obvious in the traction group,and the Talov scores at the 4th and 8th weeks after operation were lower than those in the sham group(P<0.001).The lumbosacral MRI results at 8 weeks after surgery showed that the distal filum terminale was pulled by silk thread,with bladder abnormal enlargement in sagital MRI in the traction group,while axial MRI showed the spinal cord within the spinal canal was subjected to mechanical forces in the downward and dorsal directions;the sagittal and axial MRI of the sham group showed that the spinal cord was located in the middle of the spinal canal and the bladder size was normal.At the 8th week after surgery,the amplitude in the traction group was significantly lower than that in the sham group(P<0.001),and the amplitude decreased by more than 50% .The overall latency period in the traction group was slightly longer than that in the sham group(P<0.05).The results of urodynamic examination showed that the maximum bladder capacity in the traction group was significantly higher than that in the sham group(Z=-3.361,P<0.001),the bladder pressure was significantly lower than that in the sham group(Z=-3.361,P<0.001),and the bladder compliance was significantly higher than that in the sham group(P<0.001).Pathological staining showed that the traction of the filum terminale on the spinal cord led to nerve tissue damage and degeneration of bladder epithelial cells.Conclusion This study successfully established a model of filum terminale traction tethered cord syndrome of New Zealand white rabbits,which can provide reference for exploring the pathogenesis of tethered cord and understanding the pathological process of spinal cord injury.

Objective:To compare the patient-reported outcomes and short-term clinical outcomes between robotic-assisted and laparoscopic-assisted radical gastrectomy for locally advanced gastric cancer.Methods:This single-center prospective randomized controlled trial was conducted in the Department of Gastrointestinal Surgery, Affiliated Hospital of Qingdao University from October 2020 to August 2022. Patients with locally advanced gastric cancer who were to undergo radical gastrectomy were selected and randomly divided into two groups according to 1∶1, and received robotic surgery and laparoscopic surgery, respectively. Patient-reported outcomes and short-term clinical outcomes (including postoperative complications, surgical quality and postoperative short-term recovery) were compared between the two groups by independent sample t test, Mann-Whitney U test, repeated ANOVA, generalized estimating equation, χ2 test and Fisher′s exact test. Results:A total of 237 patients were enrolled for modified intention-to-treat analysis (120 patients in the robotic group, 117 patients in the laparoscopic group). There were 180 males and 59 females, aged (63.0±10.2) years (range: 30 to 85 years). The incidence of postoperative complications was similar between the robotic group and laparoscopic group (16.7% (20/120) vs. 15.4% (18/117), χ2=0.072, P=0.788). The robotic group had higher patient-reported outcomes scores in general health status, emotional, and social domains compared to the laparoscopic group, differences in time effect, intervention effect, and interaction effect were statistically significant (general health status: χ2 value were 275.68, 3.91, 6.38, P value were <0.01, 0.048, 0.041; emotional: χ2 value were 77.79, 6.04, 6.15, P value were <0.01, 0.014, 0.046; social: χ2 value were 148.00, 7.57, 5.98, P value were <0.01, 0.006, 0.048). However, the financial burden of the robotic group was higher, the differences in time effect, intervention effect and interaction effect were statistically significant ( χ2 value were 156.24, 4.08, 36.56, P value were <0.01, 0.043,<0.01). Conclusion:Compared to the laparoscopic group, the robotic group could more effectively relieve postoperative negative emotions and improve recovery of social function in patients.

DNA replication is a fundamental DNA metabolism process in living organisms. In human cells, thousands of DNA replication origins are activated simultaneously within the chromatin environment to initiate the replication process and eventually complete genome duplication. This process is regulated by the chromatin environment and coordinated with other chromatin metabolism events, ensuring accurate inheritance of genomic and epigenetic information. With the rapid development of research techniques and the massive accumulation of research data, the systematic understanding of DNA replication in eukaryotic cells, especially in mammals, within complex chromatin environments is a future research trend. Here, we review the multilayered regulatory modes of DNA replication from initiation to termination in the chromatin environment, offering insights for future research.