BACKGROUND:Currently,numerous experiments delve into the intricate anatomy and biomechanical behavior of distinct segments of the supraspinatus muscle.However,the impact of shoulder joint stress resulting from damage to various regions of this muscle remains a scarcely explored domain.Understanding the repercussions of supraspinatus muscle injuries across different regions on the stress distribution and magnitude of articular cartilage and the glenoid is crucial for providing some theoretical support for clinical diagnosis and treatment. OBJECTIVE:To ascertain the maximum stress values by simulating different degrees of supraspinatus muscle rupture on the humeral cartilage surface,glenoid lip,and glenoid cartilage joint surface using three-dimensional finite element software. METHODS:Normal and healthy shoulder joint CT or MRI scans were processed through Mimics and Geomagic to extract molds.Subsequently,models were constructed via Solidworks.Varying degrees of supraspinatus muscle damage were simulated for each model to mimic fractures in different regions.Finally,Ansys,mechanical software,was employed for three-dimensional finite element biomechanical analysis,calculating stress values for the humeral cartilage surface,glenoid lip,and glenoid cartilage joint surface. RESULTS AND CONCLUSION:(1)With worsening degrees of supraspinatus muscle injury,the stress on the shoulder joint cartilage surface and glenoid lip escalated.(2)Among various regions,the anterior part of the supraspinatus muscle exhibited paramount significance.(3)While supraspinatus muscle fractures of differing degrees impacted the magnitude of cartilage stress on the glenoid labial surface,the stress distribution remained constant.(4)It is indicated that during the initial stages of horizontal abduction of the shoulder joint,the anterior region assumes a pivotal role,followed by the posterior deep region.Injury to the anterior part of the supraspinatus muscle leads to a significant surge in stress within the shoulder joint's soft tissue,potentially causing damage to the top of the glenoid lip and the anterior part of the glenoid cartilage.

Objective:To investigate the protective effects of resveratrol (RSV) on human sperm cryopreservation and explore its underlying protective mechanisms.Methods:A total of 165 normal fresh semen samples were collected from the Reproductive Medicine Center, Department of Obstetrics and Gynecology and Human Sperm Bank of the First Affiliated Hospital of Anhui Medical University between December 2022 and December 2024. Among them, 65 samples were used to obtain semen parameters before and after conventional freezing. Each sample of the other 104 samples was mixed at a 2∶1 volume ratio with cryoprotectant containing 0, 10 -?, 10 -?, or 10 -? mol/L RSV, followed by cryopreservation in liquid nitrogen for 24 h. Post-thaw assessments included routine sperm parameters, sperm DNA fragmentation index (DFI) evaluated by sperm chromatin dispersion assay, reactive oxygen species (ROS) levels measured via flow cytometry, RSV and nuclear factor erythroid 2-related factor 2 (NRF2) interactions examined by molecular docking and cellular thermal shift assay (CETSA), NRF2 protein contents analyzed by immunofluorescence and Western blotting, mRNA levels of NRF2 and downstream antioxidant proteins Heme Oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1) quantified by qRT-PCR and effects of NRF2 inhibitor ML385 on sperm parameters. Results:Compared with fresh samples, conventional cryopreservation significantly reduced sperm motility (all P<0.001). The addition of 10 -? mol/L RSV significantly improved the percentage of forward motile sperm after freezing (26.98%±8.98% vs. 19.61%±8.03%, P<0.001) while reducing DFI (9.84%±3.81% vs. 15.06%±4.22%, P<0.001) and ROS levels ( P<0.001) compared with the post-freezing group without the addition of RSV. Both molecular docking analysis and CETSA confirmed that RSV interacted with NRF2. Notably, sperm cryopreserved with 10 -? mol/L RSV exhibited significantly higher contents of NRF2 and its downstream effectors HO-1 and NQO1 compared with the post-freezing group without the addition of RSV (all P<0.001). This protective effect was markedly attenuated by co-treatment with the NRF2 inhibitor ML385, as evidenced by a significant decline in sperm motility ( P<0.001). Conclusion:RSV exerts cryoprotective effects likely through NRF2-mediated antioxidant pathways, reducing oxidative stress and enhancing post-thaw sperm quality.

Objective:To explore the association between the use of tetracyclines during pregnancy and congenital malformations, with the aim of providing evidence-based guidance for the rational use of antibiotics during pregnancy.Methods:Data from the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) and the Canada Vigilance Adverse Reaction (CVAR) database from January 2015 to September 2024 were collected. Five methods including Tree-based scan statistic (TreeScan), proportional reporting ratio (PRR), reporting odds ratio (ROR), the UK Medicines and Healthcare Products Regulatory Agency (MHRA) comprehensive standard, and the Bayesian confidence propagation neural network (BCPNN) were used to detect signals of risk for congenital malformations in offspring following maternal use of tetracyclines during pregnancy. A signal that met the threshold criteria of all above 5 methods was considered as a risk signal. Based on population-based cohort of the drug exposures and adverse pregnancy outcomes (DEEP) data from January 2013 to December 2021 in Xiamen City, propensity score matching (PSM)-based Poisson regression was applied to evaluate the association between the first-trimester tetracyclines exposure and congenital malformations in offspring. Adjusted relative risk (a RR) and its 95% confidence interval ( CI) were calculated. Sensitivity analysis was conducted to validate the reliability of the results. Results:A total of 304 098 reports of adverse events during pregnancy were obtained from the FAERS and CVAR databases. Among them, 5 028 reports were related to tetracyclines, including 1 026 reports of congenital malformations in offspring, involving congenital malformations of musculoskeletal system, other digestive system, and other congenital malformations. Signal detection results suggested that tetracyclines may be a risk signal for above congenital malformations in offspring. The DEEP data included 411 936 pregnant women. After PSM, 240 pregnant women exposed to tetracyclines were included. The results showed no significant association between the first-trimester tetracyclines exposure and congenital malformations in offspring (a RR=0.75, 95% CI: 0.26-2.17), sensitivity analysis also showed no correlation. Conclusions:Data mining from the FAERS and CVAR databases suggests a potential association between tetracyclines use during pregnancy and congenital malformations in offspring. However, the DEEP data study shows no significant correlation.

Objective To explore the influence of different surgical methods on the stress of knee me-niscus and patellofemoral joint surface of simulated episodic patellar dislocation using three-dimension-al finite element software under different flexion conditions.Methods The knee joint CT and MRI of pa-tients with episodic patellar dislocation were acquired and imported into Mimics and Geomagic to ex-tract the model,followed by the 0°,30°,60°,90° and 120° buckling construction using the Soild-works software.For each model,medial patellofemoral ligament reconstruction,medial retinaculum pli-cation,lateral retinaculum release,medial patellofemoral and patellotibial ligament reconstruction,as well as medial patellofemoral ligament reconstruction and lateral retinaculum release were conducted re-spectively.Finally,they were imported into the mechanical software Ansys for biomechanical analysis,and the stress results of knee meniscus and patellofemoral joint surface were output.Results The medi-al patellofemoral and patellotibial ligament reconstruction had the smallest meniscus peak stress com-pared with other methods.Moreover,it also exerted the smaller peak stress on the patellofemoral joint surface,along with the medial patellofemoral ligament reconstruction and the lateral retinaculum re-lease.Conclusion The medial patellofemoral and patellotibial ligament reconstruction can provide good patellofemoral contact stress and meniscus stress,effectively restore the stability of the knee joint.How-ever,medial patellofemoral ligament reconstruction and lateral retinaculum release can also provide bet-ter patellofemoral joint stress,but the meniscus stress is slightly higher,so we should be alert to the complications related to the meniscus after surgery.

Objective:To investigate the protective effects of resveratrol (RSV) on human sperm cryopreservation and explore its underlying protective mechanisms.Methods:A total of 165 normal fresh semen samples were collected from the Reproductive Medicine Center, Department of Obstetrics and Gynecology and Human Sperm Bank of the First Affiliated Hospital of Anhui Medical University between December 2022 and December 2024. Among them, 65 samples were used to obtain semen parameters before and after conventional freezing. Each sample of the other 104 samples was mixed at a 2∶1 volume ratio with cryoprotectant containing 0, 10 -?, 10 -?, or 10 -? mol/L RSV, followed by cryopreservation in liquid nitrogen for 24 h. Post-thaw assessments included routine sperm parameters, sperm DNA fragmentation index (DFI) evaluated by sperm chromatin dispersion assay, reactive oxygen species (ROS) levels measured via flow cytometry, RSV and nuclear factor erythroid 2-related factor 2 (NRF2) interactions examined by molecular docking and cellular thermal shift assay (CETSA), NRF2 protein contents analyzed by immunofluorescence and Western blotting, mRNA levels of NRF2 and downstream antioxidant proteins Heme Oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1) quantified by qRT-PCR and effects of NRF2 inhibitor ML385 on sperm parameters. Results:Compared with fresh samples, conventional cryopreservation significantly reduced sperm motility (all P<0.001). The addition of 10 -? mol/L RSV significantly improved the percentage of forward motile sperm after freezing (26.98%±8.98% vs. 19.61%±8.03%, P<0.001) while reducing DFI (9.84%±3.81% vs. 15.06%±4.22%, P<0.001) and ROS levels ( P<0.001) compared with the post-freezing group without the addition of RSV. Both molecular docking analysis and CETSA confirmed that RSV interacted with NRF2. Notably, sperm cryopreserved with 10 -? mol/L RSV exhibited significantly higher contents of NRF2 and its downstream effectors HO-1 and NQO1 compared with the post-freezing group without the addition of RSV (all P<0.001). This protective effect was markedly attenuated by co-treatment with the NRF2 inhibitor ML385, as evidenced by a significant decline in sperm motility ( P<0.001). Conclusion:RSV exerts cryoprotective effects likely through NRF2-mediated antioxidant pathways, reducing oxidative stress and enhancing post-thaw sperm quality.

The diagnostic value of Mycobacterium tuberculosis(MTB)complex and rifampicin resistance test kits(fluorescence PCR method)in detecting for MTB complex and rifampicin resistancein sputum samples was evaluated.A total of 271 patients with suspected tuberculosis were prospectively and consecutively enrolled at Hunan Chest Hospital between April 1,2024,and November 30,2024.Of these,229 patients were confirmed to have tuberculosis,whereas 42 patients were not-tuberculosis samples were col-lected from all patients and subjected to fluorescence PCR,Xpert MTB/RIF(abbreviated as Xpert),and MGIT 960 culture and drug sensitivity testing.Clinical diagnosis and MTB culture results served as reference standards for TB diagnosis,whereas phenotypic drug susceptibility testing and Xpert served as reference standards to for assessment of rifampicin resistance.The sensitivity,specificity,positive predictive value,and negative predictive value of the fluorescence PCR method were analyzed.Kappa tests were performed to analyze the concordance between detection techniques.With clinical diagnosis as the gold standard,the sensitivity and specificity of the fluorescence PCR method for the diagnosis of TB were 65.1%(149/229)and 97.6%(41/42),and the consistency test for the fluo-rescence PCR and Xpert methods showed high consistency(Kappa value=0.993).With the MGIT 960 liquid culture as the reference standard,the positive detection rate of the fluorescence PCR method for the detection of patients with positive cultures was 91.9%(102/111,95%CI:85.2%-96.2%),and the positive detection rate for 147 patients with sputum culture-negative TB was 27.9%(41/147,95%CI:21.3%-35.6%).With the phenotypic drug sensitivity test as the gold standard,the sensitivity and specificity of the fluo-rescence PCR method for the detection of rifampicin resistance were 100.0%(31/31)and 96.6%(28/29)respectively,and the consis-tency between tests was high(Kappa value=0.967).With Xpert as the gold standard,the sensitivity and specificity of fluorescence PCR for the detection of rifampicin resistance were 95.8%(46/48)and 99.0%(99/100),respectively,and the consistency between tests was high(Kappa value=0.953).Finally,samples with rifampicin resistance detected with the fluorescence PCR method had a clear rpoB gene mutation type according to one-generation sequencing.In conclusion,the fluorescence PCR method showed high sen-sitivity in detecting MTB complex groups and rifampicin resistance,and had high concordance with Xpert.Therefore,this technique can serve a rapid test for TB diagnosis to increase the rate of positive TB pathology and detection of rifampicin resistance.This method is particularly suitable for use in lower-income countries and economically disadvantaged grassroots communities.

BACKGROUND:The"inflammatory storm"induced by microglia is an important pathological factor causing the death of neuronal cells after spinal cord injury,which is extremely unfavorable for the recovery after spinal cord injury.Dihydroquercetin belongs to the vitamin P group and has excellent biological activity.It has good anti-inflammatory,anti-lipid peroxidation and neuroprotective effects on spinal cord injury.The mechanism by which it promotes the repair of spinal cord injury needs to be further clarified.OBJECTIVE:To investigate whether dihydroquercetin can ameliorate the inflammatory state induced after spinal cord injury through its anti-inflammatory and antioxidant properties for the purpose of protection against spinal cord injury.METHODS:Forty-eight Sprague-Dawley rats were divided into sham operation group,spinal cord injury group,low-dose dihydroquercetin group,and high-dose dihydroquercetin group according to the random number table method.The sham operation group only underwent laminectomy and was given intraperitoneal injection of normal saline after the operation.Animal models of spinal cord injury were made in the latter three groups.After the operation,normal saline,30 mg/kg,and 50 mg/kg dihydroquercetin were given by intraperitoneal injection respectively,and samples were collected 4 weeks after the operation.The Basso-Beatte-Bresnahan(BBB)limb motor function score and mechanical paw withdrawal threshold were used to evaluate the limb motor function and pain recovery of rats.Hematoxylin-eosin staining was used to observe the pathological changes of spinal cord tissue;Nissl staining was used to observe the number of Nissl bodies and the morphology of neurons.The activity of superoxide dismutase in spinal cord tissue was detected.Immunofluorescence was used to detect the expression of reactive oxygen species and microglia Iba1.Western blot was used to detect the protein expression of Iba1 and interleukin-1β,interleukin-6,interleukin-10,tumor necrosis factor-α,and p38 mitogen-activated protein kinase in the spinal cord.RESULTS AND CONCLUSION:(1)In the behavioral test,the BBB limb motor function score showed that since 14 days after the operation,the BBB limb motor function score of the high-dose dihydroquercetin group was significantly better than that of the spinal cord injury group(P<0.01);the mechanical paw withdrawal threshold was significantly lower in the high-dose dihydroquercetin than the spinal cord injury group at 21 days after the operation(P<0.05),and the former group showed better motor function.(2)Hematoxylin-eosin staining and Nissl staining showed that compared with the spinal cord injury group,the high-dose dihydroquercetin group showed slightly swollen but structurally intact and clearer neuron morphology in the spinal cord tissue,and the number of Nissl bodies increased.(3)Superoxide dismutase detection:Compared with the spinal cord injury group,the activity of superoxide dismutase in the spinal cord tissue of the high-dose dihydroquercetin increased significantly(P<0.05).(4)Reactive oxygen species immunofluorescence detection:Compared with the spinal cord injury group,the high-dose dihydroquercetin could significantly reduce the accumulation of reactive oxygen species after spinal cord injury(P<0.05).(5)Detection of microglial marker Iba1:Compared with the spinal cord injury group,the high-dose dihydroquercetin could significantly reduce the expression of microglial marker Iba1 after spinal cord injury(P<0.01).(6)Western blot detection results showed that compared with the spinal cord injury group,the expressions of inflammatory factors(interleukin-1β,interleukin-6,and tumor necrosis factor-α)and phosphorylated p38 mitogen-activated protein kinase in the high-dose dihydroquercetin group decreased significantly(P<0.01),while the expression of anti-inflammatory factor interleukin-10 increased significantly(P<0.01).These findings indicate that dihydroquercetin can effectively reverse the expression changes of multiple inflammatory markers induced after spinal cord injury in rats,thereby exerting neuroprotective effects and improving motor function.

Objective To explore the influence of different surgical methods on the stress of knee me-niscus and patellofemoral joint surface of simulated episodic patellar dislocation using three-dimension-al finite element software under different flexion conditions.Methods The knee joint CT and MRI of pa-tients with episodic patellar dislocation were acquired and imported into Mimics and Geomagic to ex-tract the model,followed by the 0°,30°,60°,90° and 120° buckling construction using the Soild-works software.For each model,medial patellofemoral ligament reconstruction,medial retinaculum pli-cation,lateral retinaculum release,medial patellofemoral and patellotibial ligament reconstruction,as well as medial patellofemoral ligament reconstruction and lateral retinaculum release were conducted re-spectively.Finally,they were imported into the mechanical software Ansys for biomechanical analysis,and the stress results of knee meniscus and patellofemoral joint surface were output.Results The medi-al patellofemoral and patellotibial ligament reconstruction had the smallest meniscus peak stress com-pared with other methods.Moreover,it also exerted the smaller peak stress on the patellofemoral joint surface,along with the medial patellofemoral ligament reconstruction and the lateral retinaculum re-lease.Conclusion The medial patellofemoral and patellotibial ligament reconstruction can provide good patellofemoral contact stress and meniscus stress,effectively restore the stability of the knee joint.How-ever,medial patellofemoral ligament reconstruction and lateral retinaculum release can also provide bet-ter patellofemoral joint stress,but the meniscus stress is slightly higher,so we should be alert to the complications related to the meniscus after surgery.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Objective: To investigate the characteristics and risk factors of an outbreak of acute hemorrhagic conjunctivitis (AHC) in a boarding middle school in Guangdong Province, in order to provide a scientific evidence for effective prevention and control of campus AHC outbreaks. Methods: From September 1st to 28th 2023, case identification was conducted among 559 students and 60 faculty members using standardized definition. Descriptive analysis was conducted on the three distrubution patterns of the outbreak. Questionnaires were designed, and a case-control study was adopted to analyze the possible risk factors of the disease transmission. The propensity score matching (PSM) method was used to control the difference of baseline data. Results: A total of 269 cases of AHC were identified, with an attack rate of 43.46%. The pathogen was confirmed as Coxsackie virus A24 variant (CA24v). Among these, 264 cases were students (attack rate of 47.23%) and 5 were staff (attack rate of 8.33%). A total of 153 pairs of PSM were successfully matched. After PSM matching, there were no statistically significant differences in gender, grade and class between the case group and the control group ( χ 2=0.12, 5.41, 11.24, P >0.05). The results of multivariate Logistic regression analysis showed that middle school students whose towels contacted with others ( OR =1.81), and direct contact with other AHC cases recently ( OR =4.89) were more likely to have AHC; while wearing glasses ( OR =0.43) and frequent use of hand sanitizer ( OR = 0.37 ) were less likely to have AHC ( P <0.05). Conclusion The outbreak of AHC is caused by CA24v, demonstrating rapid spread and extensive impact within the school setting.