Objective: To evaluate the performance of 5T magnetic resonance imaging (MRI) in visualizing dental pulp and periodontal ligament (PDL) tissues in vivo in the young adult population, thereby providing a basis for the application of high-field MRI technology in clinical oral examinations. Methods: The study was approved by the Ethics Committee of the hospital. A total of 15 healthy volunteers (413 permanent teeth altogether) were recruited and underwent full-mouth 5T MRI scans. Among them, six volunteers (168 permanent teeth) also received both 3T MRI and cone-beam computed tomography (CBCT) scans. Two dental specialists independently evaluated the imaging quality of the dental pulp and PDL on the images using a 5-point Likert scale and recorded the number of detectable root canals for each tooth. Inter-rater agreement was assessed using weighted kappa statistics and intraclass correlation coefficient (ICC). Non-parametric tests were employed to compare differences in imaging performance among different tissue structures, tooth positions, and imaging modalities. Results: 5T MRI can achieve in vivo imaging for most dental pulp tissues and partial periodontal membrane structures. There was a high level of agreement between the two raters in their imaging scores for the dental pulp and PDL (dental pulp κ = 0.934, PDL κ = 0.737). The imaging scores for dental pulp were significantly higher than those for PDL (P < 0.001), and the scores for molar dental pulp were lower than those for premolars and anterior teeth. In the multimodal comparison involving six volunteers, the raters showed good consistency in scoring dental pulp and PDL imaging across 5T MRI, 3T MRI, and CBCT, as well as in root canal counts (5T MRI for dental pulp κ = 0.971, 3T MRI for dental pulp κ = 0.933, CBCT for dental pulp κ = 0.964; 5T MRI for PDL κ = 0.625, 3T MRI for PDL κ = 0.667, CBCT for PDL κ = 0.571; ICC for root canal counts all ≥ 0.990). The imaging scores for dental pulp and PDL using 5T MRI were significantly higher than those using 3T MRI (dental pulp: P < 0.001; PDL: P = 0.022), but there was no statistically significant difference in the detection rate of the number of root canals between the two (P > 0.05). Although the imaging scores for dental pulp and PDL as well as the detection rate of the number of root canals with 5T MRI were inferior to those with CBCT (dental pulp: P < 0.001; PDL: P = 0.02; number of root canals: P < 0.05), 5T MRI can truly achieve "direct imaging" of these two soft tissues. Conclusion 5T MRI enables effective in vivo direct imaging of dental pulp and PDL tissues in the young adult population, indicating its potential clinical application value in the diagnosis and treatment of pulp and periodontal diseases.

Objective To construct a uricase-deficient mouse model with stable inheritance using the CRISPR/Cas9 system,and evaluate its ability to simulate the disease characteristics of patients with hyperuricemia.Methods Double single guide RNAs(sgRNAs)were designed on both sides of exon 2～4 of the Uox gene.sgRNA and Cas9 mRNA for gene knockout were microinjected into the fertilized eggs of mice.After culture for 2～4 h,the embryos were transferred to surrogate mother mice to produce an F0 generation.Uox-knockout mice were identified by polymerase chain reaction and sequencing analysis.Positive mice were then mated with wild-type(WT)mice to produce an F1 generation,and heterozygous female and male F1 mice were then selected to obtain homozygous F2 mice.Serum and urine levels of uric acid,creatinine,and urea,and serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)levels were detected and compared between homozygous and wild-type mice.Pathological changes in kidney and liver tissues were observed by hematoxylin and eosin and Masson staining.Results Urine levels of serum uric acid(male:(4116.8±1928.1)μmol/L,P＜0.001;female:(2998.0±547.7)μmol/L,P＜0.01)and serum levels of uric acid(male:(478.4±114.6)μmol/L,P＜0.001;female:(507.7±129.6)μmol/L,P＜0.001),creatinine((91.8±55.6)μmol/L,P＜0.001),urea((28.6±13.9)mmol/L,P＜0.05),ALT((53.3±23.3)U/L,P＜0.01),and AST((203.3±70.3)U/L,P＜0.001)were significantly increased in Uox-/-mice compared with WT mice.Histopathological examination showed moderate hepatocyte degeneration in the liver,moderate-to-severe tubular cystic dilation,degeneration,and fibrosis in the kidney,glomerular hypertrophy and hyperplasia,small-vessel dilation and congestion,and infiltration of stromal monocytes and lymphocytes in Uox-/-mice.Conclusions We successfully established a homozygous uricase-deficient mouse strain using CRISPR/Cas9 technology,as a suitable animal model for research in the field of hyperuricemia.

Objective To assist drug and pharmaceutical packaging material manufacturers in understanding and utilizing the functionality evaluation methods for prefilled syringe with Luer conical fittings,thereby scientifically specifying product quality.Methods By comparing the standards status both domestically and internationally,and in conjunction with the product characteristics,production,and actual usage situation of prefilled syringe with Luer conical fittings,the test contents and key points of related functionality evaluation methods were analyzed.Results The functionality evaluation methods for prefilled syringe with Luer conical fittings represent improvements and supplements to domestic standard,appropriate methods should be selected based on the product type.Conclusion Developing functionality evaluation methods for prefilled syringe with Luer conical fittings will provide guidance to standardized quality control for drug and pharmaceutical packaging material manufacturers.It will also better meet the requirements for market regulation,and is an effective way to promote the overall development of the industry.

OBJECTIVE To observe the clinical efficacy of Zhenshi Burn Ointment on postoperative wound healing of simple anal fistula and explore its potential mechanism of action.METHODS A total of 60 patients with low-position simple anal fistula of damp-heat pouring downward type admitted to the Department of Anorectum,Nanjing Hospital of Chinese Medicine Affiliated to Nan-jing University of Chinese Medicine from May to December 2023 were selected as the research subjects and randomly divided into an experimental group and a control group,with 30 cases in each group.After surgery,the control group was given sterilized vaseline gauze for external application,and the experimental group was given Zhenshi Burn Ointment for external application.The course of treatment for both groups was 30 d.After treatment,the postoperative wound healing time,wound healing rate,pain score,wound granulation growth and secretion,and changes in TCM syndrome score were compared between the two groups.The pathological sec-tions of wound granulation tissue were compared 14 d after surgery.The transcription levels of COL1A1,type Ⅲ collagen(COL3A1),epidermal growth factor(EGF),and fibroblast growth factor(FGF2)in granulation tissue were detected by qPCR.The expression lev-els of proteins related to MEK/ERK signaling pathway were detected by Western blot.RESULTS Compared with the control group,the wound healing rates of the experimental group were significantly increased at 7,14,21,and 30 d after surgery(P<0.01),and the wound healing time was significantly shortened(P<0.01).At 7 d after surgery,the pain score of the experimental group was signifi-cantly lower than that of the control group(P<0.05).At 7 and 14 d after surgery,the granulation growth score of the wound in the ex-perimental group was significantly lower than that of the control group(P<0.01).At 14 d after surgery,the secretion score of the ex-perimental group was significantly lower than that of the control group(P<0.01).At 14 and 30 d after surgery,the total score of TCM syndrome in the experimental group was significantly better than that in the control group(P<0.05).At 14 d after surgery,the patho-logical improvement of granulation tissue in the wound in the experimental group was better than that in the control group,and the con-tent of collagen fiber and type I collagen(Collagen I)was significantly higher than that in the control group(P<0.01).The mRNA contents of COL1A1,COL3A1,EGF,and FGF2 were significantly higher than those in the control group(P<0.05,P<0.01);the levels of p-MEK1/2 and p-ERK1/2 proteins were higher than those in the control group(P<0.05).CONCLUSION Zhenshi Burn Ointment has a good effect on promoting postoperative anal fistula wound healing,which may be related to upregulating growth factor expression,promoting collagen regeneration,and activating MEK/ERK pathway.

Objective To study the plasma metabolomics of mice poisoned by different dosage of the combination of diazepam and ethanol,and to reveal the toxicological mechanisms of combined poisoning of diazepam and ethanol.Methods Female Kunming mice were randomly divided into blank group,single and combined poisoning group(n=6),Based on the LD50 of diazepam co-administered with graded ethanol doses,mice in the single-drug and combined groups received oral gavage at 1/2,1,and 2 × LD50.Retro-orbital blood samples(～500 μL)were collected within 24 hours post-administration and analyzed by UPLC-QE-MS technology.Principal component analysis and orthogonal partial least squares discriminant analysis were used to identify differential metabolites and associated metabolic pathways.Results A total of 387 differential metabolites were identified in the combined poisoning group of diazepam and ethanol implicating the key pathways including tryptophan metabolism,phenylalanine metabolism,arginine and proline metabolism,Glycerophospholipid metabolism,phenylalanine,tyrosine and tryptophan biosynthesis.Conclusion Combined diazepam and ethanol poisoning exerts significant systemic effects by disrupting neurotransmitters conduction,exacerbating oxidative stress response and dysregulating energy metabolism.

Aim To study the diastolic effect and mechanism of farrerol on isolated pulmonary arteries of C57BL/6J mice.Methods After anesthesia,mouse lung tissue was quickly removed and placed into the 4 ℃ K-H buffer,pulmonary arteries were isolated under the microscope and cut into 2 mm long vascular rings for spare use.(1)The effect of farrerol on the resting tension of isolated mouse pulmonary arteries:in the resting state,the active mouse pul-monary artery rings were treated with different concentrations of farrerol(10-6,3×10-6,10-5,3×10-5 and 10-4 mol/L).(2)Farrerol relaxed mouse pulmonary artery experiment:pulmonary arteries were contracted using phenylephrine(PE,1 μmol/L)or KCl(60 mmol/L),and when the contraction reached the platform,different concentrations of farrerol(10-6,3×10-6,10-5,3×10-5 and 10-4 mol/L)was added.(3)Farrerol inhibited pulmonary artery contraction experi-ment:under conditions with or without the addition of farrerol,pulmonary arteries were contracted using different concen-trations of PE(10-9,3×10-9,10-8,3 × 10-8,10-7,3×10-7 and 10-6 mol/L)or KCl(20,30,40,60,80 and 120 mmol/L),and the pulmonary artery muscle tension was recorded.(4)Calcium free and recalcification experiments:under conditions with or without the addition of farrerol,the changes of isolated mouse pulmonary artery tension were meas-ured in the state of calcium free or recalcification { 2.5 mmol/L[Ca2+]ex }.(5)The relationship between farrerol in-duced relaxation of isolated mouse pulmonary arteries and potassium ion channels:firstly,60 mmol/L KCl solution was used to contract the mouse pulmonary arteries until the platform.Then,3 mmol/L aminopyridine(4-AP),2 mmol/L tet-raethylammonium(TEA),30 μmol/L BaCl2,and 10 μmol/L glibenclamide(Gli)were added and treated for 15 min.Subsequently,the pulmonary arteries were relaxed using a concentration gradient of farrerol.Results Farrerol had no significant effect on the mouse pulmonary arteries in the resting state,but had a concentration-dependent relaxing effect on the mouse pulmonary arteries pre-contracted with PE and KCl.While the pretreatment of 3×10-5 mol/L farrerol could sig-nificantly reduce the maximum contraction of mouse pulmonary arteries induced by PE and KCl(P＜0.01),as well as sig-nificantly reduce the contraction of mouse pulmonary arteries induced by KCl under calcium free or recalcification conditions(P＜0.01).Addition of the voltage-dependent potassium ion channel blocker 4-AP significantly reduced the maximum diastolic rate of mouse pulmonary arteries induced by farrerol(P＜0.01),while addition of the high conductivity calcium activated potassium ion channel blocker TEA,inward rectifying potassium ion channel blocker BaCl2,or ATP sensitive po-tassium ion channel blocker Gli had no significant effect on the vasodilation effect of farrerol(P＞0.05).Conclusion Farrerol has a relaxing effect on isolated mouse pulmonary arteries,and its mechanism may be related to open voltage-de-pendent potassium ion channels.

International studies have established that electrons, X-rays, protons, and heavy ions can all be utilized in ultra-high dose-rate radiotherapy. Among these modalities, megavoltage X-ray ultra-high dose-rate radiotherapy holds particularly broad clinical promise. With its long-term expertise in high-intensity pulsed radiation sources, the Institute of Applied Electronics at the China Academy of Engineering Physics has pioneered global solutions for generating and measuring megavoltage X-rays ultra-high dose-rate radiotherapy, positioning China at the forefront of this field. Herein, we review the development history, current status, and future trends in ultra-high dose-rate X-ray generation, measurement, and protection. The insights provided aim to serve as a reliable reference for clinical and preclinical research, equipment development, and standardization, thereby enabling more precise and reliable megavoltage ultra-high dose-rate X-ray production and measurement. We hope this work will significantly support further research and clinical translation of ultra-high dose-rate radiotherapy technology.

Objective:To establish a rapid and precise dose measurement method with EBT4 film and ensure its measurement accuracy to be within the required range through strict operational procedures for the purpose of addressing the two essential issues of poor measurement accuracy and timeliness of EBT film under FLASH conditions.Methods:After storing under different humidity conditions for a certain period of time, the film was exposed to radiation for analyzing the influence of air humidity on the intrinsic performance of EBT film. By means of repeated scanning operations and the film angle rotation, the influences of repeated scanning and film placement angle were analuzed. Parabolic correction method was used to reduce the spatial position influence during the scanning process. By analying the relationship between net optical density (netOD) and absorbed dose through the comparison of three fitting method, the optimal fitting curve was selected. After irradiation of the same batch of films for 5 min and 24 h, the film doses were calibrated and then compared with ionization chamber-measured result. The rapid and precise film dosimetry method was used to measure both the percentage depth dose from X-rays at ultra-high dose rate and the dose distribution at a depth of 2 cm in water.Results:Air humidity had the greatest influence on the intrinsic performance of EBT film (approximately 20%). The average deviation of repeated scans is within 0.5%. The angle at which the film is placed significantly affected the readouts of the film with the maximum influence approximately 70%. The net optical density combined with polynomial fitting can control the fitting residuals of 1-16 Gy within 3%. The change rate of light channels at 5 min already mostly met the requirements of the rapid mode (< 0.5%). Compared with the measurement result obtained using the reference ionization chamber, the deviations of the 5 min or 24 h dose calibration curves were all within 2%.Conclusions:The EBT4 film can be employed as a precise dosimeter to quickly measure the FLASH radiation dose. Rapid and precise FLASH dose measurements can meet the stringent requirements of both preclinical and clinical FLASH research.

Objective To construct a uricase-deficient mouse model with stable inheritance using the CRISPR/Cas9 system,and evaluate its ability to simulate the disease characteristics of patients with hyperuricemia.Methods Double single guide RNAs(sgRNAs)were designed on both sides of exon 2～4 of the Uox gene.sgRNA and Cas9 mRNA for gene knockout were microinjected into the fertilized eggs of mice.After culture for 2～4 h,the embryos were transferred to surrogate mother mice to produce an F0 generation.Uox-knockout mice were identified by polymerase chain reaction and sequencing analysis.Positive mice were then mated with wild-type(WT)mice to produce an F1 generation,and heterozygous female and male F1 mice were then selected to obtain homozygous F2 mice.Serum and urine levels of uric acid,creatinine,and urea,and serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)levels were detected and compared between homozygous and wild-type mice.Pathological changes in kidney and liver tissues were observed by hematoxylin and eosin and Masson staining.Results Urine levels of serum uric acid(male:(4116.8±1928.1)μmol/L,P＜0.001;female:(2998.0±547.7)μmol/L,P＜0.01)and serum levels of uric acid(male:(478.4±114.6)μmol/L,P＜0.001;female:(507.7±129.6)μmol/L,P＜0.001),creatinine((91.8±55.6)μmol/L,P＜0.001),urea((28.6±13.9)mmol/L,P＜0.05),ALT((53.3±23.3)U/L,P＜0.01),and AST((203.3±70.3)U/L,P＜0.001)were significantly increased in Uox-/-mice compared with WT mice.Histopathological examination showed moderate hepatocyte degeneration in the liver,moderate-to-severe tubular cystic dilation,degeneration,and fibrosis in the kidney,glomerular hypertrophy and hyperplasia,small-vessel dilation and congestion,and infiltration of stromal monocytes and lymphocytes in Uox-/-mice.Conclusions We successfully established a homozygous uricase-deficient mouse strain using CRISPR/Cas9 technology,as a suitable animal model for research in the field of hyperuricemia.

Objective To analyze the basic characteristics of patients with acute myocardial infarction in a tertiary hospi-tal from 2014 to 2023,and provide references for the prevention,treatment,management,and quality control of this disease.Methods Based on the data from the medical records of patients with acute myocardial infarction admitted to a tertiary hospital from January 1,2014,to December 31,2023,the basic characteristics of hospitalized patients and trends in hospitalization costs were analyzed to summarize the development patterns.Results Over the past decade,the number of hospitalized patients with a-cute myocardial infarction has been increasing,while the average length of hospital stay,average cost per hospitalization,and mortality rate have been decreasing.Among the 19 937 patients,there were 16 037 male patients(80.44％)and 3 900 female patients(19.56％),with a male-to-female ratio of 4.11∶1.The median age for male patients was 60 years,while for female patients it was 68 years,indicating that males tend to develop the disease approximately 10 years earlier than females.Among pa-tients aged 60 and above,the mortality rate is positively correlated with age,while among patients below 60,the mortality rate is negatively correlated with age.The decision to undergo surgery has a significant impact on hospitalization costs.From the per-spective of cost structure,the proportion of consumables has decreased from 69.81％to 54.60％in the past decade but remains relatively high.Conclusion With the advancement of hospital management and medical insurance policies,the diagnosis,treat-ment,and quality of care for acute myocardial infarction have significantly improved.However,consumables management remains a key focus.Men and individuals aged 50 and above should be given special attention.During the diagnosis and treatment process,greater attention should also be given to younger or older patients and female patients to reduce the mortality rate.