Biomechanical effects of femoral prosthesis misalignment on the structure of the lateral compartment during medial unicompartmental knee arthroplasty in osteoporotic patients.

BACKGROUND: This study aims to investigate the impact of varying coronal alignments of femoral prostheses on stress and strain distributions within the lateral compartment following unicompartmental knee arthroplasty (UKA) in patients with normal bone density and osteoporosis using finite element analysis. Additionally, it examines the relationship between osteoporosis and the progression of osteoarthritis in the lateral compartment postoperatively. METHODS: UKA models were developed for both normal bone and osteoporotic conditions using a validated finite element model of the knee. Seven alignment conditions for the femoral prosthesis were simulated: 0° (neutral alignment), varus angles of 3°, 6°, and 9°, and valgus angles of 3°, 6°, and 9°, resulting in a total of 14 scenarios. Stress and strain distributions in the meniscus, tibial cartilage, and femoral cartilage of the lateral compartment were evaluated. RESULTS: The results indicated that stress and strain in the meniscus, tibial cartilage, and femoral cartilage of the lateral compartment increased with greater varus alignment and decreased with greater valgus alignment in both normal and osteoporotic models. At equivalent alignment angles, stress and strain were consistently higher in the osteoporotic model (M2) compared to the normal bone model (M1), although the peak equivalent stress in the tibial cartilage was lower in the M2 model than in the M1 model. CONCLUSIONS: In patients with osteoporosis undergoing fixed-bearing medial UKA, varus malalignment of the femoral prosthesis can lead to increased stress and strain in the lateral compartment's meniscus, tibial cartilage, and femoral cartilage. These findings suggest that osteoporosis may contribute to abnormal stress and strain distributions in the lateral compartment following UKA, potentially accelerating the progression of osteoarthritis in this region postoperatively.

Persistence of Lugol-unstaining is associated with an increased risk of progression to malignancy in the esophagus.

BACKGROUND AND AIMS: To investigate the persistence of Lugol-unstained lesions (LULs) in the esophagus detected by chromoendoscopy and explore its association with progression to malignancy. METHODS: We enrolled 647 participants from a population-based screening trial who had biopsied LULs at the baseline chromoendoscopy and underwent a chromoendoscopy reexamination after a median of 4.39 years. Cases of persistent LUL were defined as those in whom a visible LUL was observed during reexamination at the documented location (±2cm) where a LUL was detected at baseline chromoendoscopy. Logistic regression was applied to explore risk factors for the persistence of LULs. The primary outcome was clinical-stage esophageal squamous cell carcinoma (ESCC) identified over 6.78 years of follow-up and the secondary outcome was reexamination-detected severe dysplasia and above lesions (SDA). The cumulative incidence was calculated to assess the progression risk associated with the persistence of LULs. RESULTS: The proportion of participants with persistent LULs was 81.92%. Dysplasia (adjusted OR=6.16, 95%CI: 2.70 to 17.80), large LULs (adjusted OR=1.90, 95%CI: 1.18 to 3.15), and irregularly shaped LULs (adjusted OR=1.63, 95%CI: 1.03 to 2.56) at baseline were associated with an increased risk of LUL persistence. Eleven clinical-stage ESCC cases and 31 SDAs detected during reexamination were identified, all of which originated from patients with persistent LULs (Pclinical-stageESCC =0.136, Preexamination-detected SDA =0.015). CONCLUSION: The persistence of LULs is associated with progression to malignancy in the esophagus, even in individuals without dysplastic lesions. Based on this, a more efficient post-screening surveillance strategy could be established.

Urinary alkylresorcinol metabolites, biomarkers of whole grain wheat and rye intake, are beneficially associated with liver fat and other fat measures.

Aims: Epidemiological studies that use dietary biomarkers to investigate the association between whole grain intake and the risk of obesity are sparse. We assessed the association between urinary alkylresorcinol metabolites including 3-(3,5-dihydroxyphenyl)-1-propanoic acid (DHPPA) and 3,5-dihydroxybenzoic acid (DHBA), biomarkers of whole grain wheat and rye intake, and body fat measures. Methods: We measured urinary excretion of DHPPA and DHBA, body weight, height, and circumferences of the waist and hip at the baseline and again after 1-year in a representative sample of 306 community-dwelling adults in Huoshan, China. We also measured liver fat accumulation [indicated by the controlled attenuation parameter (CAP)] and other body composition after 1 year. Multivariate-adjusted linear models and linear mixed-effects models were used to analyze single measurement and repeated measurements, respectively. Results: Each 1 µg g-1 creatinine increase in urinary DHPPA levels was associated with 0.21%, 0.23%, 3.64%, and 4.80% decrease in body weight, body mass index (BMI), body fat mass (BFM) and visceral fat level (VFL), respectively (all P < 0.05). Higher DHBA levels were inversely associated with CAP (percentage difference per 1 µg g-1 creatinine increment: -1.98%, P < 0.05). Higher total urinary alkylresorcinol metabolite (DHPPA + DHBA) levels were associated with lower body weight, BMI, BFM, VFL, and CAP, with the percentage differences per 1 µg g-1 creatinine increment of -0.27%, -0.27%, -3.79%, -5.12%, and -2.24%, respectively (all P < 0.05). Conclusions: Our findings suggest that the intake of whole grain wheat and rye, reflected by urinary DHPPA and DHBA, is favorably associated with liver fat and other fat measures.

Dynamics of Long-Term Quality of Life After Treatment for Esophageal Cancer: A Community-Based Patient Study.

PURPOSE: To characterize the pattern of post-treatment quality of life (QoL) for esophageal cancer (EC) survivors and construct models predicting their long-term QoL. METHODS: On the basis of a randomized trial in an EC high-risk region in China, we interviewed 363 EC survivors and 25,245 permanent residents matched with the survivors on age, sex, and township as the baseline. QoL was measured using three-level version of European Quality of Life 5-Dimensions instrument. We constructed piecewise mixed models estimating the QoL of EC survivors that varied by age, sex, patient type, hospital level, and therapy to ascertain QoL determinants. RESULTS: The post-treatment QoL of EC survivors dropped by 15.7% within the first year and recovered by 9.3% between 1 and 9 years compared with the baseline. Therapy was found to be a determinant of QoL, and a series of therapy-specific models were fitted accordingly, which all showed the pattern of decreasing rapidly and recovering gradually. Endoscopic treatment had the least impact on post-treatment QoL (7.5% drop within 5 years) compared with esophagectomy (12.2% drop within 1 year) and chemoradiotherapy (37.8% drop within 2 years). The usual activities dimension showed the greatest impairment among those patients (34.4% drop within 1 year). CONCLUSION: This community-based study described the long-term QoL trajectory for EC survivors after different therapeutic modalities and constructed models to predict therapy-specific QoL at different time points after treatment. It provided new insights into decision making in treatment for EC from the perspective of QoL protection, offering a convenient tool for estimating quality-adjusted life-years.

Synergistic promotion of antimony transformation in the interaction of Acidithiobacillus ferrooxidans and pyrite by driving the formation of reactive oxygen species and secondary minerals.

As one of the important microorganisms in the mining area, the role of iron-sulfur oxidizing microorganisms in antimony (element symbolized as Sb) migration and transformation in mining environments has been largely neglected for a long time. Therefore, the processes of the typical iron-sulfur oxidizing bacterium Acidithiobacillus ferrooxidans (A. ferrooxidans) and pyrite interaction coupled with the migration and transformation of Sb were investigated in this paper. The bio-oxidation process of pyrite by A. ferrooxidans not only accelerates the oxidation rate of Sb(III) to Sb(V) (62.93% of 10 mg L-1 within 4 h), but also promotes the adsorption and precipitation of Sb (32.89 % of 10 mg L-1 within 96 h), and changes in the dosage of minerals, Sb concentration, and pH value affect the conversion of Sb. The characterization results show that the interaction between A. ferrooxidans and pyrite produces a variety of reactive species, such as H2O2 and •OH, resulting in the oxidation of Sb(III). In addition, A. ferrooxidans mediates the formation of stereotyped iron-sulfur secondary minerals that can act as a major driver of Sb (especially Sb(V)) adsorption or co-precipitation. This study contributes to the further understanding of the diversified biogeochemical processes of iron-sulfur oxidizing bacteria-iron-sulfur minerals-toxic metals in mining environments and provides ideas for the development of in-situ treatment technologies for Sb.

CO2/H2 Separation by Synergistic Enhanced Hydrate Method with SDS and R134a.

The synergistic effect of thermodynamic promoter tetrafluoroethane (R134a) and kinetic promoter sodium dodecyl sulfate (SDS) can significantly improve the phase equilibrium conditions required for CO2 hydrate formation and promote rapid generation of CO2 hydrate. Based on this, this study investigates the influence of SDS and R134a synergy on the separation of CO2/H2 mixed gas using the hydrate method. The research reveals that without SDS addition, R134a hydrate forms first at the gas-liquid interface before CO2 hydrate induction, hindering gas-liquid exchange. The addition of SDS can inhibit the formation of the hydrate film, enhance the initiator effect of R134a in the CO2 hydrate formation process, accelerate the nucleation of CO2 hydrate, and thus synergistically strengthen the separation of CO2/H2 mixed gases. Hydrate formation can be achieved at a concentration of 100 ppm of SDS solution, and the synergistic growth effect of R134a and CO2 hydrate becomes more significant with increasing SDS concentration. Optimal separation efficiency and maximum H2 concentration are achieved at 500 ppm of SDS, with 42.29 and 54.88% separation efficiency and H2 concentration, respectively. Decreasing the initial charge temperature has little impact on separation efficiency but significantly reduces the induction time, reducing it to 3 min at 12 °C. This study improved the separation efficiency of CO2 and H2 mixed gas, providing a better reference for hydrogen purification by the hydrate method.

Construction and validation of serum Metabolic Risk Score for early warning of malignancy in esophagus.

Using noninvasive biomarkers to identify high-risk individuals prior to endoscopic examination is crucial for optimization of screening strategies for esophageal squamous cell carcinoma (ESCC). We conducted a nested case-control study based on two community-based screening cohorts to evaluate the warning value of serum metabolites for esophageal malignancy. The serum samples were collected at enrollment when the cases had not been diagnosed. We identified 74 differential metabolites and two prominent perturbed metabolic pathways, and constructed Metabolic Risk Score (MRS) based on 22 selected metabolic predictors. The MRS generated an area under the receiver operating characteristics curve (AUC) of 0.815. The model performed well for the within-1-year interval (AUC: 0.868) and 1-to-5-year interval (AUC: 0.845) from blood draw to diagnosis, but showed limited ability in predicting long-term cases (>5 years). In summary, the MRS could serve as a potential early warning and risk stratification tool for establishing a precision strategy of ESCC screening.

Emerging concepts in alcohol, infection & immunity: A summary of the 2023 alcohol and immunology research interest group (AIRIG) meeting.

On December 8th 2023, the annual Alcohol and Immunology Research Interest Group (AIRIG) meeting was held at the University of Colorado Anschutz Medical Campus in Aurora, Colorado. The 2023 meeting focused broadly on how acute and chronic alcohol exposure leads to immune dysregulation, and how this contributes to damage in multiple tissues and organs. These include impaired lung immunity, intestinal dysfunction, autoimmunity, the gut-Central Nervous System (CNS) axis, and end-organ damage. In addition, diverse areas of alcohol research covered multiple pathways behind alcohol-induced cellular dysfunction, including inflammasome activation, changes in miRNA expression, mitochondrial metabolism, gene regulation, and transcriptomics. Finally, the work presented at this meeting highlighted novel biomarkers and therapeutic interventions for patients suffering from alcohol-induced organ damage.

Effectiveness of Endoscopic Screening on Esophageal Cancer Incidence and Mortality: A 9-Year Report of the Endoscopic Screening for Esophageal Cancer in China (ESECC) Randomized Trial.

PURPOSE: To evaluate the effectiveness of endoscopic screening against incidence of and mortality from esophageal squamous cell carcinoma (ESCC). METHODS: From January 2012 to September 2016, we conducted a community-based cluster randomized controlled trial involving permanent residents age 45-69 years in a high-risk region for ESCC in northern China. A total of 668 targeted villages were randomly assigned in a 1:1 ratio to the screening group (offered Lugol's chromoendoscopy) or control group (no screening). Intention-to-treat and per-protocol analyses were performed to compare esophageal cancer (EC) incidence and mortality between the two groups. The per-protocol analysis adjusted for nonadherence to the screening procedure. RESULTS: A total of 33,847 participants were included in the analysis: 17,104 in the screening group, 15,165 (88.7%) of whom underwent screening, and 16,743 in the control group. During a maximum follow-up of 9 years, EC incidence in the screening and control groups were 60.9 and 72.5 per 100,000 person-years, respectively; mortality in the screening and control groups were 29.7 and 32.4 per 100,000 person-years, respectively. Compared with the control group, the incidence and mortality of the screening group reduced by 19% (adjusted hazard ratio [aHR], 0.81 [95% CI, 0.60 to 1.09]) and 18% (aHR, 0.82 [95% CI, 0.53 to 1.26]), respectively, in the intention-to-treat analysis; and by 22% (aHR, 0.78 [95% CI, 0.56 to 1.10]) and 21% (aHR, 0.79 [95% CI, 0.49 to 1.30]), respectively, in the per-protocol analysis. CONCLUSION: With a 9-year follow-up, our trial suggests that chromoendoscopic screening induces modest reductions in EC incidence and mortality. A more efficient strategy for EC screening and subsequent patient management should be established to guarantee the effectiveness of endoscopic screening.

Development and external validation of a quantitative diagnostic model for malignant gastric lesions in clinical opportunistic screening: A multicenter real-world study.

BACKGROUND: Clinical opportunistic screening is a cost-effective cancer screening modality. This study aimed to establish an easy-to-use diagnostic model serving as a risk stratification tool for identification of individuals with malignant gastric lesions for opportunistic screening. METHODS: We developed a questionnaire-based diagnostic model using a joint dataset including two clinical cohorts from northern and southern China. The cohorts consisted of 17,360 outpatients who had undergone upper gastrointestinal endoscopic examination in endoscopic clinics. The final model was derived based on unconditional logistic regression, and predictors were selected according to the Akaike information criterion. External validation was carried out with 32,614 participants from a community-based randomized controlled trial. RESULTS: This questionnaire-based diagnostic model for malignant gastric lesions had eight predictors, including advanced age, male gender, family history of gastric cancer, low body mass index, unexplained weight loss, consumption of leftover food, consumption of preserved food, and epigastric pain. This model showed high discriminative power in the development set with an area under the receiver operating characteristic curve (AUC) of 0.791 (95% confidence interval [CI]: 0.750-0.831). External validation of the model in the general population generated an AUC of 0.696 (95% CI: 0.570-0.822). This model showed an ideal ability for enriching prevalent malignant gastric lesions when applied to various scenarios. CONCLUSION: This easy-to-use questionnaire-based model for diagnosis of prevalent malignant gastric lesions may serve as an effective prescreening tool in clinical opportunistic screening for gastric cancer.

Surgical quality determines the long-term survival superiority of right over left thoracic esophagectomy for localized esophageal squamous cell carcinoma patients: a real-world multicenter study.

OBJECTIVE: The objective was to compare the long-term overall survival (OS) of right versus left thoracic esophagectomy, and to evaluate whether surgical quality impacts comparison result. BACKGROUND: Controversy regarding the optimal thoracic esophagectomy approach persists for esophageal squamous cell carcinoma (ESCC). No study has assessed the effect of surgical quality in comparison between right and left approaches. METHODS: The authors consecutively recruited 5556 operable ESCC patients from two high-volume centers in China, of whom 2220 and 3336 received right and left thoracic esophagectomy, respectively. Cumulative sum was used to evaluate the learning curve for operation time of right approach, as the indicator of surgical proficiency. RESULTS: With a median follow-up of 83.1 months, right approach, harvesting more lymph nodes, tended to have a better OS than left approach (Mean: 23.8 vs. 16.7 nodes; adjusted hazard ratio (HR)=0.93, 95% CI: 0.85-1.02). Subset analysis by the extent of lymphadenectomy demonstrated that right approach with adequate lymphadenectomy (≥15 nodes) resulted in statistically significant OS benefit compared with left approach (adjusted HR=0.86, 95% CI: 0.77-0.95), but not with limited lymphadenectomy. Subset analysis by surgical proficiency showed that proficient right approach conferred a better OS than left approach (adjusted HR=0.75, 95% CI: 0.64-0.88), but improficient right approach did not have such survival advantage. CONCLUSIONS: Surgical quality plays a crucial role in survival comparison between surgical procedures. Right thoracic esophagectomy performed with adequate lymphadenectomy and surgical proficiency, conferring more favorable survival than left approach, should be recommended as the preferred surgical procedure for localized ESCC.

The dynamic recruitment of LAB proteins senses meiotic chromosome axis differentiation in C. elegans.

During meiosis, cohesin and meiosis-specific proteins organize chromatin into an axis-loop architecture, coordinating homologous synapsis, recombination, and ordered chromosome segregation. However, how the meiotic chromosome axis is assembled and differentiated with meiotic progression remains elusive. Here, we explore the dynamic recruitment of two long arms of the bivalent proteins, LAB-1 and LAB-2, in Caenorhabditis elegans. LAB proteins directly interact with the axis core HORMA complexes and weak interactions contribute to their recruitment. LAB proteins phase separate in vitro, and this capacity is promoted by HORMA complexes. During early prophase, synapsis oppositely regulates the axis enrichment of LAB proteins. After the pachytene exit, LAB proteins switch from a reciprocal localization pattern to a colocalization pattern, and the normal dynamic pattern of LAB proteins is altered in meiotic mutants. We propose that LAB recruitment senses axis differentiation, and phase separation of meiotic structures helps subdomain establishment and accurate segregation of the chromosomes.

Integrating Surrounding Vehicle Information for Vehicle Trajectory Representation and Abnormal Lane-Change Behavior Detection.

The detection of abnormal lane-changing behavior in road vehicles has applications in traffic management and law enforcement. The primary approach to achieving this detection involves utilizing sensor data to characterize vehicle trajectories, extract distinctive parameters, and establish a detection model. Abnormal lane-changing behaviors can lead to unsafe interactions with surrounding vehicles, thereby increasing traffic risks. Therefore, solely focusing on individual vehicle perspectives and neglecting the influence of surrounding vehicles in abnormal lane-changing behavior detection has limitations. To address this, this study proposes a framework for abnormal lane-changing behavior detection. Initially, the study introduces a novel approach for representing vehicle trajectories that integrates information from surrounding vehicles. This facilitates the extraction of feature parameters considering the interactions between vehicles and distinguishing between different phases of lane-changing. The Light Gradient Boosting Machine (LGBM) algorithm is then employed to construct an abnormal lane-changing behavior detection model. The results indicate that this framework exhibits high detection accuracy, with the integration of surrounding vehicle information making a significant contribution to the detection outcomes.

Postoperative serum squamous cell carcinoma antigen and carcinoembryonic antigen predict overall survival in surgical patients with esophageal squamous cell carcinoma.

Background: Tumor markers are routinely used in clinical practice. However, for resectable patients with esophageal squamous cell carcinoma (ESCC), they are applied infrequently as their prognostic significance is incompletely understood. Methods: This historical cohort study included 2769 patients with resected ESCC from 2011 to 2018 in a high-risk area in northern China. Their clinical data were extracted from the Electronic Medical Record. Survival analysis of eight common tumor markers was performed with multivariable Cox proportional hazards regressions. Results: With a median follow-up of 39.5 months, 901 deaths occurred. Among the eight target markers, elevated postoperative serum SCC (Squamous cell carcinoma antigen) and CEA (Carcinoembryonic antigen) predicted poor overall survival (SCC HRadjusted: 2.67, 95% CI: 1.70-4.17; CEA HRadjusted: 2.36, 95% CI: 1.14-4.86). In contrast, preoperative levels were not significantly associated with survival. Stratified analysis also demonstrated poorer survival in seropositive groups of postoperative SCC and CEA within each TNM stage. The above associations were generally robust using different quantiles of concentrations above the upper limit of the clinical normal range as alternative cutoffs. Regarding temporal trends of serum levels, SCC and CEA were similar. Their concentrations fell rapidly after surgery and thereafter remained relatively stable. Conclusion: Postoperative serum SCC and CEA levels predict the overall survival of ESCC surgical patients. More importance should be attached to the use of these markers in clinical applications.

Lugol-unstained lesions location in the esophagus affects the detection rate of malignancy: a population-based study.

INTRODUCTION: This study aimed to evaluate the impact of Lugol-unstained lesion (LUL) location on the detection yield, which may help the endoscopist select targets for biopsy. METHODS: We enrolled 1064 subjects who had LULs at the baseline screening of a population-based randomized controlled trial. There were 1166 LULs with recorded location and pathologic diagnosis, and these were used for analysis. The detection rate of severe dysplasia and above (SDA) was calculated as the number of LULs identified as SDA divided by the number of LULs biopsied. Logistic regression with a generalized estimating equation was applied to evaluate the association between the location of a given LUL and the risk of the LUL being SDA. RESULTS: The detection rate of SDA for LULs located in the lower, middle, and upper esophagus increased from 5.9% and 10.9% to 16.7%. LUL location was significantly associated with having SDA (adjusted odds ratio (OR)upper vs. lower  = 2.88, 95% confidential interval (CI) = 1.48-5.60; adjusted ORmiddle vs. lower  = 1.63, 95% CI = 0.96-2.76), and the association was stronger in subgroups with a family history of esophageal squamous cell carcinoma (ESCC) (adjusted ORupper vs. lower  = 9.72, 95% CI = 2.57-36.69; adjusted ORmiddle vs. lower  = 3.76, 95% CI = 0.93-15.21). CONCLUSIONS: Our results suggest that more attention should be paid by endoscopists to LULs in the upper and middle esophagus, particularly for individuals with a family history of ESCC.

How should extra-large Lugol-unstained lesions of the esophagus be treated? Results from a population-based cohort study.

BACKGROUND: Current guidelines recommend only severe dysplasia and above (SDA) lesions of the esophageal squamous epithelium for clinical intervention. However, the histopathologic diagnosis derived from tissue biopsies may be subject to underestimation of severity. METHODS: 1073 participants from whom biopsies were taken at baseline chromoendoscopic examination in a population-based screening trial were enrolled in this study. The size of the Lugol-unstained lesions (LULs) was mainly analyzed. The outcome was defined as SDA lesions either identified at baseline screening, or during follow-up, collectively referred to as the cumulative risk of SDA. Multivariable logistic regression models were used to evaluate the cumulative risk of SDA. RESULTS: One hundred and forty-six SDA cases were identified in the study period. Participants with large LULs had a high cumulative incidence of SDA (cumulative incidence16-20mm : 55.88%; cumulative incidence>20mm : 76.92%) in the median of 7-year duration. LULs of large size were significantly associated with a higher cumulative risk of SDA, regardless of the pathologic diagnosis (adjusted OR16-20mmvs.≤5mm = 21.02, 95% CI: 7.56-58.47; adjusted OR>20mmvs.≤5mm = 33.62, 95% CI: 11.79-95.87). CONCLUSIONS: Results from this study suggest physician-patient shared decision-making regarding clinical treatment or intensive surveillance should be carried out for LULs >20 mm in the esophagus, regardless of the histologic diagnosis. For those with LULs of 16-20 mm, intensive surveillance would also best be considered.

Absence of Lugol staining indicates initiation of esophageal squamous cell carcinoma: A combined genomic and epidemiologic study.

The genomic characteristics during the carcinogenic process of esophageal squamous cell carcinoma (ESCC) remain largely unknown. We report here the genomic characteristics of 106 esophageal tissues of various stages from a population-based screening cohort in China ("Endoscopic Screening for Esophageal Cancer in China" trial) and 57 ESCC tissues from a local hospital. A significant increase in somatic mutation and copy number alterations is observed in the non-dysplastic Lugol unstaining lesions (ND-LULs). Extensive clonal expansion has emerged in the ND-LULs to an extent similar to that in higher-stage lesions. The burden of genomic alterations correlates with the size of LULs in the ND-LULs. 8-year follow-up shows that ND-LULs harbor an increased risk of progression to ESCC (adjusted IRR6-10 mm vs. none = 4.66, adjusted IRR>10 mm vs. none = 40.70), and the risk is correlated with LUL size for both non-dysplastic and dysplastic lesions. Lugol unstaining can be the initial stage in the carcinogenic process of ESCC.

[Effect of Kartogenin combined with adipose-derived stem cells on tendon-bone healing after anterior cruciate ligament reconstruction].

Objective: To investigate the effect of Kartogenin (KGN) combined with adipose-derived stem cells (ADSCs) on tendon-bone healing after anterior cruciate ligament (ACL) reconstruction in rabbits. Methods: After the primary ADSCs were cultured by passaging, the 3rd generation cells were cultured with 10 µmol/L KGN solution for 72 hours. The supernatant of KGN-ADSCs was harvested and mixed with fibrin glue at a ratio of 1∶1; the 3rd generation ADSCs were mixed with fibrin glue as a control. Eighty adult New Zealand white rabbits were taken and randomly divided into 4 groups: saline group (group A), ADSCs group (group B), KGN-ADSCs group (group C), and sham-operated group (group D). After the ACL reconstruction model was prepared in groups A-C, the saline, the mixture of ADSCs and fibrin glue, and the mixture of supernatant of KGN-ADSCs and fibrin glue were injected into the tendon-bone interface and tendon gap, respectively. ACL was only exposed without other treatment in group D. The general conditions of the animals were observed after operation. At 6 and 12 weeks, the tendon-bone interface tissues and ACL specimens were taken and the tendon-bone healing was observed by HE staining, c-Jun N-terminal kinase (JNK) immunohistochemical staining, and TUNEL apoptosis assay. The fibroblasts were counted, and the positive expression rate of JNK protein and apoptosis index (AI) were measured. At the same time point, the tensile strength test was performed to measure the maximum load and the maximum tensile distance to observe the biomechanical properties. Results: Twenty-eight rabbits were excluded from the study due to incision infection or death, and finally 12, 12, 12, and 16 rabbits in groups A-D were included in the study, respectively. After operation, the tendon-bone interface of groups A and B healed poorly, while group C healed well. At 6 and 12 weeks, the number of fibroblasts and positive expression rate of JNK protein in group C were significantly higher than those of groups A, B, and D (P<0.05). Compared with 6 weeks, the number of fibroblasts gradually decreased and the positive expression rate of JNK protein and AI decreased in group C at 12 weeks after operation, with significant differences (P<0.05). Biomechanical tests showed that the maximum loads at 6 and 12 weeks after operation in group C were higher than in groups A and B, but lower than those in group D, while the maximum tensile distance results were opposite, but the differences between groups were significant (P<0.05). Conclusion: After ACL reconstruction, local injection of a mixture of KGN-ADSCs and fibrin glue can promote the tendon-bone healing and enhance the mechanical strength and tensile resistance of the tendon-bone interface.

Different internal fixation methods for Hoffa-like fractures of the tibial plateau: a finite element analysis.

Due to the low incidence of posteromedial tibial plateau fractures and limited clinical data available, the optimal treatment for this type of fracture remains to be established. This type of fracture, also known as Hoffa-like fracture of the tibial plateau, shares a similar mechanism of injury with the Hoffa fracture of the femoral condyle. In the field of orthopedics, finite element analysis is considered a valuable method to guide clinical decision-making. In this study, four methods used for internal fixation of Hoffa-like fractures of the tibial plateau were compared using computer simulation and applying a finite element method (FEM). The methods compared were lateral L-plate fixation alone (Model A); lateral L-plate combined with posterior anti-slip plate (reconstruction plate/T-plate) fixation (Model B); lateral L-plate combined with posterior hollow nail fixation of the fracture block (Model C); and lateral L-plate combined with anterior hollow nail fixation of the fracture (Model D). The maximum displacement of the model and the maximum stress of the internal fixation material were analyzed by applying an axial load of 2,500 N. The results showed that, in the normal bone model, the maximum displacement of the fracture in Model A was 0.60032 mm, with improved stability through the addition of posterior lateral plate fixation in Model B and reduction of the displacement to 0.38882 mm. The maximum displacement in Model C and Model D was comparable, amounting to 0.42345 mm and 0.42273 mm, respectively. Maximum stress was 1235.6 MPa for Model A, 84.724 MPa for Model B, 99.805 MPa for Model C, and 103.19 MPa for Model D. In the internal fixation analysis of the osteoporotic fracture model, we observed patterns similar to the results of the normal bone model. The results indicated that Model B yielded the overall best results in the treatment of Hoffa-like fractures of the tibial plateau. The orthopedic surgeon may wish to implement these insights into the perioperative algorithm, thereby refining and optimizing clinical patient care. In addition, our findings pave the way for future research efforts.