Corneal alkali burns are a common form of corneal trauma, and their treatment has been a challenge in ophthalmology. Traditional treatments include anti-inflammatory, immunosuppressive, and corneal transplantation, with limited results. This review focuses on the research progress of mesenchymal stem cells(MSCs)and their derived extracellular vesicles(MSCs-EVs)in the treatment of corneal alkali burns. MSCs have the ability of self-renewal, multidirectional differentiation, and immunomodulation, and the MSCs-EVs inherit its function from MSCs. MSCs-EVs inherit the functions of MSCs and has lower immunogenicity and better biocompatibility, which provides a new avenue for ophthalmic treatment. In addition, bioscaffolds are used as scaffolds or drug delivery systems in tissue engineering to promote tissue regeneration due to their excellent biocompatibility and degradability. This article reviews the mechanism of action and research progress of MSCs-EVs and combined bioscaffolds in the treatment of corneal alkali burns, and explores their potential in promoting the repair of corneal alkali burns and improving vision. These findings provide new strategies for the treatment of corneal alkali burns and are expected to improve the prognosis of patients.

Corneal alkali burns are a common form of corneal trauma, and their treatment has been a challenge in ophthalmology. Traditional treatments include anti-inflammatory, immunosuppressive, and corneal transplantation, with limited results. This review focuses on the research progress of mesenchymal stem cells(MSCs)and their derived extracellular vesicles(MSCs-EVs)in the treatment of corneal alkali burns. MSCs have the ability of self-renewal, multidirectional differentiation, and immunomodulation, and the MSCs-EVs inherit its function from MSCs. MSCs-EVs inherit the functions of MSCs and has lower immunogenicity and better biocompatibility, which provides a new avenue for ophthalmic treatment. In addition, bioscaffolds are used as scaffolds or drug delivery systems in tissue engineering to promote tissue regeneration due to their excellent biocompatibility and degradability. This article reviews the mechanism of action and research progress of MSCs-EVs and combined bioscaffolds in the treatment of corneal alkali burns, and explores their potential in promoting the repair of corneal alkali burns and improving vision. These findings provide new strategies for the treatment of corneal alkali burns and are expected to improve the prognosis of patients.

BACKGROUND:Traditional surgery for lumbar disc herniation involves extensive excision of tissue surrounding the nerve for decompression and removal of protruding lumbar intervertebral discs,which poses various risks and complications such as nerve damage causing paralysis,lumbar instability,herniation recurrence,intervertebral space infection,and adjacent vertebral diseases. OBJECTIVE:To propose the symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous technique for lumbar spine symmetrically decompression,showing the induced resorption of herniated nucleus pulpous phenomenon and early clinical efficacy,and then analyze its decompression mechanism. METHODS:214 patients with lumbar disc herniation at Department of Orthopedics,First Affiliated Hospital of Zhengzhou University from March 2021 to May 2023 were enrolled in this study.Among them,81 patients received conservative treatment as the control group,and 133 patients received symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous treatment as the trial group.Before surgery,immediately after surgery(7-14 days),and early after surgery(over 1 year),MRI images were used to measure the volume changes of lumbar disc herniation.CT images were used to measure the posterior displacement distance of the lumbar spinous process ligament complex,as well as the width and height of the lateral recess.Japanese Orthopaedic Association scores were used to evaluate the patient's neurological function recovery. RESULTS AND CONCLUSION:(1)Control group:81 patients with lumbar disc herniation were treated conservatively,with a total of 171 herniated lumbar discs.The average follow-up time was(22.7±23.1)months.The first and second MRI measurements of 171 herniated lumbar discs showed herniated lumbar disc volumes of(551.6±257.9)mm3 and(792.2±330.4)mm3,respectively,with an average volume increase rate of(53.2±44.4)%,showing statistically significant differences(P<0.001).Out of 171 herniated lumbar discs,4 experienced natural shrinkage,with an absorption ratio of 2.3%(4/171)and an absorption rate of(24.5±9.9)%.(2)Trial group:133 patients with lumbar disc herniation had a total of 285 herniated lumbar discs.(1)Immediately after surgery:All patients were followed up immediately after surgery.229 out of 285 herniated lumbar discs experienced retraction,with an absorption ratio of 80.3%(229/285)and an average absorption rate of(21.5±20.9)%,with significant and complete absorption accounting for 6.5%.There were a total of 70 herniated lumbar discs in the upper lumbar spine,with an absorption ratio of 85.7%(60/70),an average absorption rate of(23.1±19.5)%,and a maximum absorption rate of 86.6%.There were 215 herniated lumbar discs in the lower lumbar spine,with an absorption ratio of 78.6%(169/215),an average absorption rate of(21.0±21.3)%,and a maximum absorption rate of 83.2%.Significant and complete absorption of the upper and lower lumbar vertebrae accounted for 5.7%and 6.5%,respectively,with no statistically significant difference(P>0.05).The average distance of posterior displacement of the spinous process ligament complex immediately after surgery was(5.2±2.8)mm.There were no significant differences in the width and height of the left and right lateral recess before and immediately after surgery(P>0.05).The Japanese Orthopaedic Association score immediately after surgery increased from(10.1±3.4)before surgery to(17.0±4.8),and the immediate effective rate after surgery reached 95.6%.(2)Early postoperative period:Among them,46 patients completed the early postoperative follow-up.There were 101 herniated lumbar discs,with an absorption ratio of 94%(95/101)and an average absorption rate of(36.9±23.7)%.Significant and complete absorption accounted for 30.6%,with a maximum absorption rate of 100%.Out of 101 herniated lumbar discs,3 remained unchanged in volume,with a volume invariance rate of 2.97%(3/101).Out of 101 herniated lumbar discs,3 had an increased volume of herniated lumbar discs,with an increase ratio of 2.97%(3/101)and an increase rate of(18.5±18.4)%.The Japanese Orthopaedic Association score increased from preoperative(9.3±5.1)to(23.5±4.0),with an excellent and good rate of 93.4%.(3)The early postoperative lumbar disc herniation absorption ratios of the control group and trial group were 2.3%and 85.9%,respectively,with statistically significant differences(P<0.001).(4)Complications:There were two cases of incision exudation and delayed healing in the trial group.After conservative treatment such as dressing change,no nerve injury or death occurred in the incision healing,and no cases underwent a second surgery.(5)It is concluded that symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous is a new method for treating lumbar disc herniation that can avoid extensive excision of the"ring"nerve and achieve satisfactory early clinical efficacy.It does not damage the lumbar facet joints or alter the basic anatomical structure of the lateral recess,fully preserves the herniated lumbar discs,and can induce significant or even complete induced resorption of herniated nucleus pulpous.Symmetrically adduction of lumbar decompression induced resorption of herniated nucleus pulpous provides a new basis and method for the clinical treatment of lumbar disc herniation.

Objective: To explore the efficacy and surgical techniques of ultrasound-assisted transurethral flexible ureteroscopic holmium laser incision and internal drainage in the treatment of special renal cystic diseases，so as to provide reference for the diagnosis and treatment of such diseases. Methods: The clinical data of 48 patients with special renal cystic diseases treated during Jan.2019 and May 2023 were retrospectively analyzed.The diagnosis was made by computed tomography urography (CTU) and three dimensional urinary tract reconstruction before operation.All patients received the abovementioned surgery in semisupine lithotomy position.The general information，clinical data，and incidence of complications were analyzed. Results: There were 27 males and 21 females，with an average age of (48.0±7.5) years，including 22 cases of parapelvic cysts，6 cases of endogenic simple renal cysts with an average diameter of (5.0±1.0) cm，and 20 cases of renal calyceal diverticulum with stones，with an average diameter of (2.5±1.3) cm for the diverticulum and an average diameter of (1.5±1.0) cm for the stones，which were located in the upper or middle calyces.In 7 cases，ureteroscopic localization was difficult，and the surgery was completed with percutaneous renal puncture needle assisted localization.Ureteral stenosis was detected in 2 cases during surgery，and surgery was performed 4 weeks after double J tubes were placed.The remaining operations were successfully completed.The average operation time was (42.0±14.5) minutes，and average hospital stay was (2.0±0.5) days.During the follow-up of (12.0±8.5) months，lumbar pain improved in 27 cases (100%)，renal cysts disappeared in 23 cases (82.1%,23/28)，cysts significantly reduced by ≥50% in 4 cases (14.3%,4/28)，slightly reduced by <50% in 1 case (3.6%,1/28)，and the renal calyx diverticulum disappeared in 20 cases (100%).Gross hematuria and lower back pain occurred in 2 cases，and no other complications developed. Conclusion: Ultrasound-guided transurethral flexible ureteroscopic holmium laser incision and internal drainage is a safe and effective treatment for special benign renal cystic diseases.When ultrasound-guided flexible ureteroscope localization is difficult to perform，percutaneous renal puncture needle may be applied.

AIM: To understand the current status and differences in visual acuity of children of the same age from different regions of Xi'an, and to take an effective basis for the prevention of children's myopia.METHODS: Random stratified sampling was used to select the uncorrected distance visual acuity and computed dioptric data of 41 285 children aged 6-12 from 6 towns, 10 urban and rural areas and 112 country schools screened by Xi'an Central Hospital in December 2022.RESULTS: The myopia detection rate in different regions of Xi'an is 47.16% in towns, 38.59% in urban and rural areas, and 32.29% in the country, and the total myopia rate is 37.50%. The myopia rate of 6-12 years old in towns is higher than that in urban and rural areas, and that of urban and rural areas is higher than that of country; the myopia rate of girls is higher than that of boys; myopia rate increases with age; mild myopia: the myopia rate in towns is significantly higher than that of the urban and rural areas and the country; high myopia: the myopia rate in the country is significantly higher than that of the towns and the urban and rural areas. The total rate of deficient hyperopia reserves in different regions of Xi'an is 92.08% in towns, 93.67% in urban and rural areas, and 90.92% in the country, and the total rate of deficient hyperopia reserves is 92.09%. The rate of deficient hyperopia reserves at the age of 6-12 is higher in the urban and rural areas than in the towns, and higher in the towns than in the country; the total rate of deficient hyperopia reserve is higher in girls than in boys; it is the peak period of the development of hyperopia reserve rate before the age of 8.CONCLUSION: The total myopia rate and the total vision reserve deficiency rate of 6-12 years old in different regions of Xi'an are different, and 8-9 years old is the accelerated period of myopia development, and the peak of deficient hyperopia reserve is before the age of 8 years old. With the growth of age, the myopia rate shows a certain growth trend, and the rate of deficient hyperopia reserve shows a decreasing trend after reaching the peak. The total myopia rate and insufficient acuity reserve rate of girls are higher than those of boys.

Objective:To evaluate the short-term efficacy and safety of 3D printing patient-matched artificial vertebral body in clinical research and application.Methods:A total of 12 patients with spinal tumors were enrolled 7 males (58.33%) and 5 females (41.67%), aged from 18 to 65 years old in The First Affiliated Hospital of Air Force military Medical University (hereinafter referred to as Xijing Hospital) and Peking University people's Hospital from September 2021 to July 2022. The spinal vertebra defect were restored by using 3D printing patient-matched artificial vertebral body after tumor resection. All patients who accepted TES and 3D printing patient-matched artificial vertebral body implantation were included according to the inclusion and exclusion criteria. The bone interface fusion was evaluated by the imaging fusion criteria of Brantigan and Steffee at 3 and 6 months after operation, the curative effect was evaluated by comparing Japanese Orthopaedic Association (JOA) score at 3 and 6 months after operation, visual analogue scale (VAS) 3 months after operation and intervertebral height at 3 and 6 months after operation with those before operation, and the safety was evaluated by adverse event recording.Results:All 12 patients completed the operation successfully, and the operation sites were thoracic vertebrae in 6 cases (50%), thoracolumbar in 3 cases (25%) and lumbar vertebrae in 3 cases (25%). All patients were followed up. The mean follow-up time was 23.92±3.23 months (range, 19-29 months). No tumor recurrence or metastasis was observed during this period. All patients were followed up at 15 days, 3 months and 6 months after operation. During the 6-month follow-up, X ray results showed that interface of bone and the vertebral body were fused in all of the 12 patients, and the effective rate of fusion was 100%. The 95% confidence interval is calculated to be (75.6%-100%). Six months after operation, the improvement rate of JOA score was excellent in 10 cases, good in 1 case, poor in 1 case, and the excellent and good rate was 91.66%. The preoperative VAS score was 4.08 ±2.47, and during the 3-month follow-up, the VAS score was improved to 1.83 ±1.59. Compared with the preoperative VAS score, the difference was statistically significant ( t=2.635, P=0.023). The intervertebral height before operation, 15 days after operation, 3 months after operation and 6 months after operation were 32.75 (25.94, 68.20), 41.09 (30.55, 70.20), 40.70 (30.23, 67.83) and 40.74 (30.23, 67.08), respectively, and there was no statistically significant difference (χ 2=0.768, P=0.857). No implant-related adverse events occurred after operation. Conclusion:The 3D printing patient-matched artificial vertebral body used in this study has satisfactory short-term efficacy and safety in the reconstruction of spinal stability after spinal tumor resection.

Objective To investigate the level of coagulation factor Ⅺ(FⅪ)in patients with venous thrombosis of lower limbs and its correlation with recurrence risk.Methods A total of 220 pa-tients with deep vein thrombosis(DVT)admitted in our hospital from February 2018 to February 2019 were enrolled as the study group,and another 50 healthy individuals taking physical exami-nation during same period served as the control group.After a 3 years followed,the study group ultimately included 197 cases,according to the results of restricted cubic spline(RCS),the study group was divided into low(FⅪ＜10.3 U/L,94 cases),medium-(10.3-12.1 U/L,52 cases)and high-level groups(＞12.1 U/L,51 cases).The plasma level of FⅪ was detected in the study group 1 month after the end of anticoagulant therapy,and the results were compared with those of the control group during physical examination.Cox model was used to analyze the influence of FⅪ on the recurrence of DVT,and RCS was employed to analyze the relationship between DVT recur-rence and FⅪ level.Kaplan-Meier curve was plotted to analyze the recurrence risk of DVT with different FⅪ levels.The patients from the study group were followed up for 3 years.Results The FⅪ level was significantly higher in the study group than the control group(P＜0.05).During fol-low-up period,33 patients(16.75％)had DVT recurrence.The Cox model analysis after adjust-ment of sex and age showed that FⅪ level was a risk factor for DVT recurrence(P＜0.05).When the FⅪ level was set into tertile and the risk ratio was calculated after adjustment,FⅪ＜10.3 U/L,and the average FⅪ level at this stage was 9.2 U/L,the risk ratio was 0.82(95％CI:0.673-0.984);Patients with FⅪ between 10.3 and 12.1 U/L,and the average FⅪ at this stage was 11.4 U/L,the risk ratio of 1.04(95％CI:0.813-1.432).The those with FⅪ＞12.1 U/L,and the average FⅪ at this stage was 13.8 U/L,hazard ratio of 1.38(95％CI:0.921-1.563).Kaplan-Meier curve analysis showed that the recurrence risk was 28.62％(95％CI:25.633-31.609),30.10％(95％CI:27.594-32.606)and 38.06％(95％CI:34.306-41.371),respectively for the low-,medium-,and high-level groups,with significant correlation among the three groups(x2=6.631,P=0.036).Conclusion Compared with healthy individuals,plasma FⅪ level is at a high level in the DVT patients.With the increment of FⅪ level,the risk of DVT recurrence increases.Two FⅪ levels,10.3 U/L and 12.1 U/L,can be used as reference points for the obvious increase of DVT recur-rence rate.

Objective:To investigate the association between congenital hypothyroidism (CH) and the adverse outcomes during hospitalization in very low birth weight infants (VLBWI).Methods:This prospective, multicenter observational cohort study was conducted based on the data from the Sino-northern Neonatal Network (SNN). Data of 5 818 VLBWI with birth weight <1 500 g and gestational age between 24-<37 weeks that were admitted to the 37 neonatal intensive care units from January 1 st, 2019 to December 31 st, 2022 were collected and analyzed. Thyroid function was first screened at 7 to 10 days after birth, followed by weekly tests within the first 4 weeks, and retested at 36 weeks of corrected gestational age or before discharge. The VLBWI were assigned to the CH group or non-CH group. Chi-square test, Fisher exact probability method, Wilcoxon rank sum test, univariate and multivariate Logistic regression were used to analyze the relationship between CH and poor prognosis during hospitalization in VLBWI. Results:A total of 5 818 eligible VLBWI were enrolled, with 2 982 (51.3%) males and the gestational age of 30 (29, 31) weeks. The incidence of CH was 5.5% (319 VLBWI). Among the CH group, only 121 VLBWI (37.9%) were diagnosed at the first screening. Univariate Logistic regression analysis showed that CH was associated with increased incidence of extrauterine growth retardation (EUGR) ( OR=1.31(1.04-1.64), P<0.05) and retinopathy of prematurity (ROP) of stage Ⅲ and above ( OR=1.74(1.11-2.75), P<0.05). However, multivariate Logistic regression analysis showed no significant correlation between CH and EUGR, moderate to severe bronchopulmonary dysplasia, grade Ⅲ to Ⅳ intraventricular hemorrhage, neonatal necrotizing enterocolitis in stage Ⅱ or above, and ROP in stage Ⅲ or above ( OR=1.04 (0.81-1.33), 0.79 (0.54-1.15), 1.15 (0.58-2.26), 1.43 (0.81-2.53), 1.12 (0.70-1.80), all P>0.05). Conclusion:There is no significant correlation between CH and in-hospital adverse outcomes, possibly due to timely diagnosis and active replacement therapy.

The tendon-bone interface is where the tendons or ligaments are connected with the bones. A spectrum of injuries may happen to the "soft-to-hard" tissue interface, including those to the rotator cuff-bone and cruciate ligament-bone interfaces, which are often precipitated by a combination of degenerative changes on the tendon-bone interface and acute or chronic injuries, thus severely impairing the patients′ motor function. In recent years, with the deepening of the interdisciplinary researches in biomechanics, mechanobiology, and sports medicine, the role of mechanical factors in the repair of tendon-bone interface injuries has attracted more and more attention and becomes a focus of the edge-cutting researches on the tendon-bone interface injuries. To this end, the authors proposed the concept of "tendon-bone interface mechanomedicine" based on an overview of the relevant researches at home and abroad. The mechanical properties of the tendon-bone interface and the effects of mechanical stimuli on its biological behavior were elucidated from the four aspects: biomechanics, mechanobiology, mechanodiagnostics, and mechanotherapy, aiming to explore the diagnostic and therapeutic strategies for tendon-bone interface injuries from the angle of mechanics and provide new perspectives and methodologies for the field of tendon-bone interface injury repair.

In order to isolate Mycoplasma hyopneumoniae(Mhp)and select virulent strains with high growth titer from the isolates to acclimate at high temperature to obtain attenuated strains.Forty lung and trachea tissues were aseptically collected from pigs suspected of Mhp in several farms in Nanyang City.A total of 6 strains of Mhp were isolated through pathogen isolation,colony observation,PCR identification and sequencing.For each isolate,round colonies with neat edges,dewdrop like particles and ridges in the center were observed on solid medium.PCR could amplify the target gene bands of each isolated P36.After sequencing,the amplified products were compared with the gene sequences of ATCC 25934 reference strain(J strain)P36 registered in NCBI,and the homology was more than 99％.The growth titer of TH-1 strain measured by CCU experiment could reach 1011 CCU/mL,which showed a high growth titer.TH-1 strain was selected for continu-ous passage at high temperature(40 ℃)in vitro to obtain different passages(P50,P1 00,P1 50).TH-1 P150 still had a higher growth titer(1010 CCU/mL)at 40 ℃ growth temperature.TH-1 P1,P50,P100 and P150 were injected into the trachea to infect 25-day-old weaned piglets,and the re-sults of virulence evaluation showed that 4 pigs(4/5)in the P1 infection group had typical"meat or shrimp meat"lesions,and serious monocyte and lymphocyte infiltration were found in the lung HE pathological sections,and the cilia were clutter-tangled,shortened and exfoliated.P150 infec-tion group did not show typical Mhp characteristic lesions,lung HE and tracheal scan sections did not show microscopic pathological changes,indicating that TH-1 was a virulent strain,but its viru-lence was continuously decreased after continuous in vitro passage,and TH-1 P150 was a low-viru-lence strain.TH-1 P150 strain,as a attenuated vaccine strain,has good immunogenicity,and the av-erage reduction rate of pneumonia disease after immune challenge was 83.3％.In conclusion,a low-virulence strain with high growth titer(TH-1 P150)was obtained by continuous passage at high temperature in vitro for the first time,and its immunogenicity was good,which laid the foundation for further research and development of Mhp attenuated vaccine.