Cataract is the world's leading cause of blindness, and surgery is the most effective treatment for cataract. With the development of femtosecond laser technology and ophthalmic surgical equipment, the application of femtosecond laser systems in cataract surgery is becoming increasingly widespread. It can be used in cataract surgery for corneal incisions, anterior capsulotomy, lens fragmentation, arcuate incisions and other key operations. Compared to traditional surgery, femtosecond laser assisted cataract surgery(FLACS)offers significant advantages in precision, safety and postoperative visual outcomes. Its clinical benefits have garnered growing recognition among ophthalmologists. However, the key technologies and high-precision equipment for FLACS remain predominantly controlled by Western countries. In China, the research in this field began later. This article reviews the technological advancements in FLACS, with a focus on femtosecond laser technology, optical coherence tomography(OCT), artificial intelligence, and clinical application progress. The objective is to provide theoretical foundations and practical insights for the development of ophthalmic medical technology in China.

BACKGROUND:Transcranial direct current stimulation(tDCS),as a non-invasive brain stimulation technique,can enhance human muscle strength or improve single-leg landing stability instantly,but no relevant research has demonstrated this yet. OBJECTIVE:To investigate the effect of tDCS on the stability of single-leg landings in human subjects. METHODS:Male undergraduate students from Wuhan Sports University were recruited as study participants.They were divided into two groups,A(n=6)and B(n=5),using a random number table.Group A underwent a sham stimulation session followed by a 3-day washout period,after which they received tDCS.Conversely,Group B received tDCS initially,followed by a 3-day washout period,and subsequently underwent the sham stimulation session.Following the respective stimulation sessions,an immediate single-leg landing test was administered to assess and collect biomechanical parameters.Data resulting from the tDCS intervention were aggregated and analyzed as the experimental group dataset,whereas data stemming from the sham stimulation were consolidated as the control group dataset. RESULTS AND CONCLUSION:Regarding core stability,the tDCS intervention showed a significant interaction with landing height on the maximal trunk flexion angle(P＜0.05).A paired comparison of the data showed a significant decrease in the maximum trunk flexion angle following true stimulation compared to sham stimulation at a 30-cm landing height.Additionally,the tDCS intervention had a significant main effect on the maximum trunk lateral bending angle and the mean trunk lateral bending angular velocity(P＜0.05).Following true stimulation,there was a significant decrease in the maximum trunk lateral bending angle and the mean trunk lateral bending angular velocity compared to sham stimulation.In terms of lower limb joint stability,the tDCS intervention had a significant main effect on the maximum dynamic ankle valgus angle(P＜0.05).This resulted in a significant decrease in the angle following true stimulation compared to sham stimulation.In addition,the tDCS intervention had a significant main effect on the peak muscle activation of the lateral head of the gastrocnemius lateralis(P＜0.05).This showed a significant increase after true stimulation compared to sham stimulation.An interaction between the tDCS intervention and landing height was observed for the peak muscle activation of the tibialis anterior(P＜0.05).Paired comparison analyses revealed a significant increase in muscle activation after true stimulation specifically at a 60-cm landing height.Regarding center of pressure stability,there were no significant interactions or main effects of the tDCS intervention on the mean lateral displacement,mean lateral displacement velocity,mean anterior-posterior displacement,or mean anterior-posterior displacement velocity at the center of pressure(P＞0.05).Furthermore,the tDCS intervention had no significant main effects on any of the center of pressure indicators(P＞0.05).In conclusion,tDCS can immediately improve core stability and lower limb joint stability during single-leg landing,making it an effective warm-up technique for improving single-leg landing stability and reducing the risk of lower limb injuries.

Objective To compare the therapeutic effects of manual reduction and machine reduction in patients with benign paroxysmal positional vertigo(BPPV)at different ages.Methods Randomly select 300 patients clinically diagnosed with BPPV who visited the Hearing Center of the First Affiliated Hospital of Wenzhou Medical University from April 2022 to December 2023.They were divided into young and middle-aged group of 170 cases(18-59 years old)and elderly group of 130 cases(≥60 years old)according to age.Each group was further divided equally into experimental group and control group based on the diagnosis and treatment methods adopted by the patients.The experimental group patients were treated with a benign paroxysmal positional vertigo diagnosis and treatment system(model/specification:SRM-Ⅳ)for machine reduction.The control group patients were treated with manual reduction.Compare the effective rate of reduction,reduction frequency,incidence of residual dizziness symptoms,and duration of each group.Results In young and middle-aged patients,the incidence and duration of residual dizziness symptoms after reduction in experimental group were significantly lower than those in control group(P<0.05),and there was no statistically significant difference in the effective rate and number of reductions(P>0.05).In elderly group,the reduction efficiency of experimental group was significantly higher than that of control group,and the reduction frequency was lower than that of the control group(P<0.05).There was no statistically significant difference in the incidence and duration of residual dizziness symptoms after reduction(P>0.05).Conclusion Machine reduction can significantly improve the reduction efficiency of elderly BPPV patients,significantly shorten the duration of residual dizziness after reduction treatment in young and middle-aged patients,and reduce its incidence.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period，9 035 strains of Gram-negative bacteria were collected from 51 hospitals，of which 7 895（87.4%）were Enterobacteriaceae and 1 140（12.6%）were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli（ n=4 510，49.9%）， Klebsiella pneumoniae（ n=2 340，25.9%）， Pseudomonas aeruginosa（ n=534，5.9%）， Acinetobacter baumannii complex（ n=405，4.5%）and Enterobacter cloacae（ n=327，3.6%）. The ESBLs-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus spp. were 47.1%（2 095/4 452），21.0%（427/2 033）and 41.1%（58/141），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（58/4 510）and 13.1%（307/2 340）；62.1%（36/58）and 9.8%（30/307）of CREC and CRKP were resistant to ceftazidime/avibactam combination，respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 59.5%（241/405），while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 18.4%（98/534）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions，with statistically significant differences in the prevalence of CRKP and CRPA（ χ2=20.489 and 20.252， P<0.001）. The prevalence of CREC，CRKP，CRPA，CRAB，ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals（ χ2=11.953，81.183，10.404，5.915，12.415 and 6.459， P<0.01 or <0.05），while the prevalence of CRPA was higher in economically developed regions（per capita GDP ≥ 92 059 Yuan）than that in economically less-developed regions（per capita GDP <92 059 Yuan）（ χ2=6.240， P=0.012）. Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend，and Escherichia coli is ranked in the top，while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different，and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.

Objective:To compare the clinical effects between the homodigital radial flap of the dorsal cutaneous branch of radial palmar proper digital artery (PPDA) and the homodigital reverse island flap of the ulnar dorsal digital artery (DDA) on reconstruction of defects in thumb-tip or thumb-pulp.Methods:The retrospective case-control study method was used. From January 2016 to August 2022, a total of 65 thumb-tip or thumb-pulp defects were treated in the Department of Hand Surgery of the Second Hospital of Tangshan. Thirty-five defects of thumbs were reconstructed with the homodigital radial flap pedicled with dorsal cutaneous branch of radial PPDA (PPDA group) and the other 30 thumbs were treated by the homodigital ulnar reverse island flap pedicled with ulnar DDA (DDA group). Sizes of the wounds and flaps in PPDA group were 1.9 cm×1.5 cm to 2.9 cm×2.4 cm and 2.1 cm× 1.7 cm to 3.1 cm×2.6 cm, respectively, and the dimensions of the wounds and flaps in DDA group were 2.0 cm× 1.7 cm to 2.9 cm×2.5 cm and 2.2 cm×1.9 cm to 3.2 cm×2.8 cm, respectively. The wounds of donor site in both groups were all directly closed. Survival of the flaps and wound healing of donor sites were observed in both groups. The time of surgery and duration of follow-up of the 2 groups were recorded. Postoperative follow-up included outpatient clinic visits, telephone reviews and WeChat video-clips. At the final follow-up, record of total active motion (TAM) of the injured thumbs, angle of first web of the affected hands, static TPD of the flaps, patient satisfaction of the appearance of flaps and donor sites were taken. According to the Michigan Hand Function Questionnaire (MHQ) evaluation criteria, the patient satisfaction of the appearance of flaps and donor sites were evaluated. The measurement and count data acquired from both groups were compared by independent sample t-test and χ2 tests or Fisher's exact test, respectively. P<0.05 was considered statistically significant. Results:All 35 flaps in PPDA group and 26 flaps in DDA group survived primarily, except 4 flaps in the DDA group that showed blisters and healed with dressing changes. The primary survival rate of flap in PPDA group (100%) was higher than that of DDA group (87%), and the difference was statistically significant ( P<0.05). Donor sites of both groups healed primary. The time of surgery and duration of follow-up in PPDA and DDA groups were 59.11 minutes±5.42 minutes and 15.37 months±3.32 months, and 61.27 minutes±5.96 minutes and 16.17 months±3.60 months, respectively. There was no statistically significant difference between the 2 groups ( P>0.05). At the final follow-up, the thumb TAM and angle of thumb web in PPDA and DDA groups were 135.14°±10.04° and 90.29°±4.36° and 132.17°±11.04° and 89.00°±4.81°, respectively. There was no statistically significant differences between the 2 groups ( P>0.05). The static TPD, patient satisfaction of the appearance of flaps and donor sites in PPDA group were 7.11 mm±1.21 mm, 4.69 point±0.47 point and 4.43 point±0.50 point, which were better than DDA group [8.20 mm±1.47 mm, 4.40 point±0.50 point and 4.13 point±0.57 point, respectively] with a statistically significant difference ( P<0.05). Conclusion:The homodigital radial flap of the dorsal cutaneous branch of radial PPDA and the homodigital ulnar reverse island flap of the ulnar DDA are both suitable for reconstruction of defects in thumb-tip or thumb-pulp. Compared with the homodigital reverse island flap with the DDA, a homodigital radial flap with the dorsal cutaneous branch of PPDA has advantages in higher primary survival rate, better flap sensation and appearance at both of recipient and donor sites.

Objective To analyze the risk of return to sport in athletes using their gait data following anterior cruciate ligament re-construction(ACLR). Methods From May to June,2023,39 athletes after ACLR were recruited in Wuhan Sports University.Their data on sta-ble gait and tandem gait were recorded using a three-dimensional motion capture system,surface electromyogra-phy and a three-dimensional ergometer table.Additionally,return-to-sport scores were calculated using the K-STARTS test.The relationship between each gait indicator and the total score of the K-STARTS test was ana-lyzed with Pearson correlation analysis.Furthermore,the key indicators related to the risk of return to sport were analyzed using linear regression. Results In the stable gait test,the step time was negatively correlated with the total score of K-STARTS(r=-0.479,P=0.002),and the peak amplitude symmetry index of rectus femoris(r=0.448,P=0.004)and vastus lateralis(r=0.595,P=0.001)were positively correlated with the total score of K-STARTS.In the tandem gait test,the lateral displacement distance of the center of gravity was negatively correlated with the total score of K-STARTS(r=-0.341,P=0.034),and the time symmetry index of peak amplitude of vastus lateralis was positively correlated with the total score of K-STARTS(r=0.320,P=0.047).Regression analysis showed that the interpretation of the model based on stable gait(F=15.818,P=0.001,R2=0.650)was better than that based on tandem gait(F=7.692,P=0.001,R2=0.397). Conclusion In stable gait,gait rhythm variability and symmetry are correlated with return to sport risk.In tandem gait,gait balance and symmetry indexes are correlated with return-to-sport risk.Compared with tandem gait,the inter-pretation of return-to-sport risk assessment model based on stable gait information is better,and may be more suitable as a simple return-to-sport risk test method.

AIM:To investigate the role of ClC-3 chloride channel in the promotion of radio sensitization of na-sopharyngeal carcinoma CNE-2Z cells by dihydroartemisinin(DHA).METHODS:MTT was used to detect the inhibito-ry effect of DHA on the viability of CNE-2Z cells and normal nasopharyngeal epithelial NP69-SV40T cells,the radio sensi-tization effect of DHA on CNE-2Z cells was detected by cloning assay,the expression of ClC-3 protein was detected by Western blot,the expression of ClC-3 protein was down-regulated by siRNA technology,and the chlorine current of cells was recorded by whole cell patch-clamp technology.RESULTS:(1)Compared with NP69-SV40T cells,DHA selective-ly inhibited the proliferation of CNE-2Z cells,with IC10 values of(13.020±4.831)μmol/L and(5.244±1.050)μmol/L,respectively(P＜0.01).(2)The results of clonal formation experiments showed that DHA had a radio sensitizing effect on CNE-2Z cells,with a radio sensitization ratio of 1.9.(3)DHA could activate the chlorine channel of CNE-2Z cells and produce an outward chlorine current,but had no effect on the chlorine channel of NP69-SV40T cells.(4)DHA promoted the expression of ClC-3 chloric channel protein in CNE-2Z cells(P＜0.01).(5)Chlorine channel blocker NPPB could in-hibit the radio sensitizing effect of DHA on CNE-2Z cells by 1.84 times,and also inhibited the chlorine current activated by DHA.(6)the down-regulation of CNE-2Z ClC-3 protein could inhibit the radio sensitization effect of DHA on CNE-2Z cells by 4.19 times,and the activation of chlorine current by DHA on CNE-2Z cells was no longer produced.CONCLU-SION:DHA has a radio sensitizing effect on nasopharyngeal carcinoma CNE-2Z cells,which is likely to be related to the activation of ClC-3 chloride channel.

Objective:To compare the prognostic values of different classification by using transpulmonary pressure gradient (TPG), diastolic pressure gradient (DPG) and pulmonary vascular resistance (PVR) in patients with pulmonary hypertension due to left heart disease (PH-LHD), and investigated hemodynamic and clinical factors associated with mortality in patients with PH-LHD.Methods:This was a single-center prospective cohort study. In-hospital patients diagnosed with PH-LHD via right heart catheterization at the Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, from September 2013 to December 2019 were enrolled. Patients were divided according to TPG (cutoff value 12 mmHg; 1 mmHg=0.133 kPa), DPG (cutoff value 7 mmHg), PVR (cutoff value 3 Wood Units), and the combination of TPG and PVR. Baseline characteristic was recorded. All patients were followed up until the occurrence of endpoint event, defined as all-cause death that occurred during the follow-up period, or until April 18, 2022. Receiver operating characteristic curves were used to compare the predictive value of 3 classification methods for all-cause death in PH-LHD patients. The optimal cutoff values were calculated using Jorden index. Survival analysis was performed using Kaplan-Meier analysis, and log-rank test was used to compare the predictive efficacy of classification methods based on optimal cutoff values or guidance-recommended thresholds for the survival of PH-LHD patients. Variables showing statistical significance in the univariate analysis were incorporated into multivariate Cox regression model to analyze the independent risk factors for all-cause mortality.Results:A total of 243 patients were enrolled, aged (54.9±12.7) years old, including 169 (69.5%) males. During a median follow-up of 57 months, there were 101 (41.6%) deaths occurred. Grouping results were as follows: (1) TPG: TPG≤12 mmHg group 115 patients, TPG>12 mmHg group 128 patients; (2) DPG: DPG<7 mmHg group 193 patients, DPG≥7 mmHg group 50 patients; (3) PVR: PVR≤3 Wood Units group 108 patients, PVR>3 Wood Units group 135 patients; (4) TPG and PVR: TPG≤12 mmHg and PVR≤3 Wood Units group 89 patients, TPG>12 mmHg and PVR>3 Wood Units group 109 patients. PVR ( AUC=0. 698,95% CI:0.631-0.766) had better predictive value for all-cause mortality than TPG ( AUC=0.596, 95% CI: 0.523-0.669) and DPG ( AUC=0.526, 95% CI: 0.452-0.601) (all P<0.05). The optimal cutoff values for TPG, DPG, and PVR were13.9 mmHg, 2.8 mmHg, and 3.8 Wood Units, respectively. Kaplan-Meier analysis based on the optimal cutoff values or guidance-recommended thresholds showed that PVR and TPG were the predictors of survival ( P<0.05), while DPG did not showed significance ( P>0.05). Multivariate Cox regression analysis showed that age, PVR and log 2N-terminal pro-B-type natriuretic peptide were independent risk factors for all-cause mortality in PH-LHD patients (all P<0.05). Conclusion:Classification according to PVR was most valuable in predicting all-cause death in PH-LHD patients, while TPG showed moderate predictive ability and DPG had no predictive value.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective To compare the effects of six composite fixatives on paraffin sections of golden hamster retinal tissue, and to optimize the fixation methods for retinal tissue paraffin sections of golden hamsters. Methods Eighteen male SPF grade golden hamsters were taken and randomly divided into six groups of three animals each. After each animal was anesthetized by intraperitoneal injection of sodium pentobarbital, cardiac perfusion was performed using 4% paraformaldehyde, Bouin's, Carnoy, Davidson's, Zenker, and Helly fixatives, respectively. The eye tissues of each animal were taken out to make eye cups and put into the corresponding compound fixative solution for fixation, and then taken out for paraffin embedding after 48 h. The embedded blocks were sliced using microtome, and then stained with hematoxylin and eosin (HE). The morphological characteristics of retinal tissue cells were observed under a light microscope and scored in a double-blind method to statistically analyze the fixation effect and staining quality of various composite fixative solutions. ResultsRetinal sections fixed with Davidson's fixative exhibited intact morphology without breaks, clear structural layers, well-morphosed nuclei, and tight adhesion between the retina, sclera, and uvea. In contrast, sections fixed with 4% paraformaldehyde, Bouin's, and Carnoy fixatives showed varying degrees of retinal breaks and detachment from the sclera. Sections fixed with Zenker and Helly fixatives demonstrated the poorest quality, characterized by pronounced detachment, large fissures, unclear cell layers, and pale staining. Statistical analysis using SPSS 27.0 software revealed significant differences in mean scores among the six fixatives (P<0.001). The fixation quality ranking was as follows: Davidson's fixative > 4% paraformaldehyde > Bouin's fixative > Carnoy fixative > Helly fixative > Zenker fixative. Zenker and Helly fixatives showed significantly lower scores than the other fixatives (P<0.001), while no significant differences were observed among the remaining fixatives (P>0.05). Conclusion Davidson's fixative provides the best fixation and staining results, followed by 4% paraformaldehyde and Bouin's fixative. Carnoy fixative exhibits suboptimal performance, while Zenker and Helly fixatives result in the poorest outcomes. Therefore, Davidson's fixative is recommended as the optimal fixative for golden hamster retinal tissue, with 4% paraformaldehyde, Bouin's and Carnoy fixatives as alternative options.