Comparison of the medial midline and the anterolateral portal in ankle arthroscopy for the treatment of osteochondral lesions of the medial talus.

PURPOSE: To compare the clinical efficacy and complication rates between the medial midline and anterolateral portals in ankle arthroscopy for treating medial osteochondral lesions of the talus (OLTs). METHODS: We retrospectively analyzed patients with medial OLTs who underwent either a dual medial approach (via the medial midline and anteromedial portal) or a traditional approach (via the anterolateral and anteromedial portal) between June 2017 and January 2023. The degree of injury was evaluated by radiographs, computed tomography, and magnetic resonance imaging. Clinical outcomes were assessed using the visual analog scale (VAS), the American Orthopaedic Foot and Ankle Society (AOFAS) score, and the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) scoring system. The incidence of postoperative complications, including superficial peroneal nerve (SPN) injury, was evaluated in all patients. RESULTS: There were 39 patients in total; 16 patients underwent the dual medial approach, and 23 patients underwent the traditional approach. The mean age was 39.4 ± 9.0 years, and the mean follow-up duration was 18.7 ± 6.4 months. The clinical outcomes improved significantly in both groups (*P < 0.05), but there was no significant difference between the two groups (P > 0.05). Postoperative complications were mainly SPN injury. The incidence of SPN injury was 13.0% in the traditional approach group and 0% in the dual medial approach group, with no significant difference between the two groups (P > 0.05), but a trend of reduction in SPN injury was observed in the dual medial approach group. CONCLUSION: The dual medial approach can also treat medial OLTs well, providing clear visualization and more convenient operation and reducing the possibility of injury to the SPN compared with the traditional approach. Therefore, we consider that the MM portal would be a good alternative to the anterolateral portal in treating medial OLTs.

Associations of long-term exposure to air pollution with prevalence of pulmonary nodules: A cross-sectional study in Shijiazhuang, China.

A complete understanding of the associations of ambient air pollution with prevalence of pulmonary nodule is lacking. We aimed to investigate the associations of ambient air pollutants with prevalence of pulmonary nodule. A total of 9991 health examination participants was enrolled and 3166 was elected in the final in Shijiazhuang between April 1st, 2018, and December 31st, 2018. 107 participants were diagnosed in pulmonary nodule while 3059 participants were diagnosed in non-pulmonary (named control). The individual exposure of participants was evaluation by Empirical Bayesian Kriging model according to their residential or work addresses. The pulmonary nodules were found and diagnosed by health examination through chest x-ray detection. Our results suggested that there were positive associations between prevalence of pulmonary nodules and PM2.5 (OR = 1.06, 95% CI: 1.02, 1.11) as well as O3 (OR = 1.49, 95% CI: 1.35, 1.66) levels. The platelet count (PLT) acted as the mediator of pulmonary nodules related with the PM2.5 exposure, while the neutrophil-to-lymphocyte ratio (NLR) as well as platelet-to-lymphocyte ratio (PLR) were the mediators of pulmonary nodules related with the O3 exposure. This study suggests that long-term exposure to PM2.5 and O3 may significantly associated with prevalence of pulmonary nodules, and the above associations are mediated by PLT, NLR and PLR.

FDX1 regulates leydig cell ferroptosis mediates PM2.5-induced testicular dysfunction of mice.

Epidemiological studies have established an association between chronic exposure to PM2.5 and male infertility. However, the underlying mechanisms were not fully revealed. In this study, we established mice models exposed to PM2.5 for 16 weeks, and a significant decrease in sperm quality accompanied by an increase in testosterone levels were observed after PM2.5 exposure. Moreover, treatment with ferrostatin-1 (Fer-1), a specific ferroptosis inhibitor, effectively mitigated PM2.5-induced testicular dysfunction in mice. And lipid peroxidation and ferritin accumulation were found to be significantly increased in Leydig cells of testes with a PM2.5-dose dependent manner. Further investigations revealed that TM-3 cells, a mouse Leydig cell line, were prone to ferroptosis after PM2.5 exposure, and the cell viability was partly rescued after the intervention of Fer-1. Furthermore, our results supported that the ferroptosis of TM-3 cells was attributed to the upregulation of ferredoxin 1 (FDX1), which was the protein transferring electrons to cytochrome P450 family 11 subfamily A member 1 to aid lysing cholesterol to pregnenolone at initial of steroidogenesis. Mechanically, PM2.5-induced FDX1 upregulation resulted in cellular ROS elevation and ferrous iron overload, which together initiated an autoxidation process of polyunsaturated fatty acids in the cell membrane of Leydig cells until the accumulated lipid peroxides triggered ferroptotic cell death. Simultaneously, upregulation of FDX1 promoted steroidogenesis and let to an increased level of testosterone. In summary, our work suggested that FDX1, a mediator involving steroidogenesis, was a key regulator in PM2.5-induced Leydig cells ferroptosis.

Gas6-Axl signal promotes indoor VOCs exposure-induced pulmonary fibrosis via pulmonary microvascular endothelial cells-fibroblasts cross-talk.

Volatile organic compounds (VOCs) as environmental pollutants were associated with respiratory diseases. Pulmonary fibrosis (PF) was characterized by an increase of extracellular matrix, leading to deterioration of lung function. The adverse effects on lung and the potential mechanism underlying VOCs induced PF had not been elucidated clearly. In this study, the indoor VOCs exposure mouse model along with an ex vivo biosensor assay was established. Based on scRNA-seq analysis, the adverse effects on lung and potential molecular mechanism were studied. Herein, the results showed that VOCs exposure from indoor decoration contributed to decreased lung function and facilitated pulmonary fibrosis in mice. Then, the whole lung cell atlas after VOCs exposure and the heterogeneity of fibroblasts were revealed. We explored the molecular interactions among various pulmonary cells, suggesting that endothelial cells contributed to fibroblasts activation in response to VOCs exposure. Mechanistically, pulmonary microvascular endothelial cells (MPVECs) secreted Gas6 after VOCs-induced PANoptosis phenotype, bound to the Axl in fibroblasts, and then activated fibroblasts. Moreover, Atf3 as the key gene negatively regulated PANoptosis phenotype to ameliorate fibrosis induced by VOCs exposure. These novel findings provided a new perspective about MPVECs could serve as the initiating factor of PF induced by VOCs exposure.

Experimental study on repair of cartilage defects in the rabbits with GelMA-MSCs scaffold prepared by three-dimensional bioprinting.

Cartilage damage is a common orthopedic disease, which can be caused by sports injury, obesity, joint wear, and aging, and cannot be repaired by itself. Surgical autologous osteochondral grafting is often required in deep osteochondral lesions to avoid the later progression of osteoarthritis. In this study, we fabricated a gelatin methacryloyl-marrow mesenchymal stem cells (GelMA-MSCs) scaffold by three-dimensional (3D) bioprinting. This bioink is capable of fast gel photocuring and spontaneous covalent cross-linking, which can maintain high viability of MSCs and provide a benign microenvironment to promote the interaction, migration, and proliferation of cells. In vivo experiments, further, proved that the 3D bioprinting scaffold can promote the regeneration of cartilage collagen fibers and have a remarkable effect on cartilage repair of rabbit cartilage injury model, which may represent a general and versatile strategy for precise engineering of cartilage regeneration system.

Site-specific Atg13 methylation-mediated autophagy regulates epithelial inflammation in PM2.5-induced pulmonary fibrosis.

Fine particulate matters (PM2.5) increased the risk of pulmonary fibrosis. However, the regulatory mechanisms of lung epithelium in pulmonary fibrosis remained elusive. Here we developed PM2.5-exposure lung epithelial cells and mice models to investigate the role of autophagy in lung epithelia mediating inflammation and pulmonary fibrosis. PM2.5 exposure induced autophagy in lung epithelial cells and then drove pulmonary fibrosis by activation of NF-κB/NLRP3 signaling pathway. PM2.5-downregulated ALKBH5 protein expression promotes m6A modification of Atg13 mRNA at site 767 in lung epithelial cells. Atg13-mediated ULK complex positively regulated autophagy and inflammation in epithelial cells with PM2.5 treatment. Knockout of ALKBH5 in mice further accelerated ULK complex-regulated autophagy, inflammation and pulmonary fibrosis. Thus, our results highlighted that site-specific m6A methylation on Atg13 mRNA regulated epithelial inflammation-driven pulmonary fibrosis in an autophagy-dependent manner upon PM2.5 exposure, and it provided target intervention strategies towards PM2.5-induced pulmonary fibrosis.

Genetic instability of lung induced by carbon black nanoparticles is related with Plk1 signals changes.

As a possible carcinogen, carbon black has threatened public health. However, the evidences are insufficient and the mechanism of carcinogenesis is still not specified. Thirty rats were randomly divided into 3 groups, namely 0, 5 and 30 mg/m3 Carbon Black nanoparticles (CBNPs) groups, respectively. Rats were treated with CBNPs by nose-only inhalation for 28 days, 6 h/day. The human bronchial epithelial (16HBE) cells were treated with 0, 50, 100 and 200 µg/mL CBNPs for 24 h. Polo-like kinase 1 (PLK1) overexpression cell line was established by pcDNA3.1-PLK1 stable transfection. Our results showed that CBNPs exposure could induce DNA damage and genetic changes as well as apoptosis in vivo and in vitro. The DNA repair ability increased after CBNPs exposure. Cell cycle process was retarded at the G2/M phases in 16HBE cells after CBNPs treatment. The PLK1, ChK2 GADD45α and XRCC1 expression levels changed in rat lung and 16HBE cells after CBNPs treatment. Compared with NC 16HBE cells, DNA damage and repair, numbers of apoptotic cells and micronucleus (MN) rates, as well as the ChK2, GADD45α, XRCC1 expression levels decreased, whereas cytokinesis block proliferation index (CBPI) and replicative index (RI) increase in PLK overexpression (PLK+/+) cells after CBNPs treatment. This study highlighted that PLK1 related with the genetic toxicity of CBNPs in vitro and in vivo. Our results provided evidences supporting reclassification of carbon black as a human possible carcinogen.

Expression Profile of Long Noncoding RNAs and Circular RNAs in Mouse C3H10T1/2 Mesenchymal Stem Cells Undergoing Myogenic and Cardiomyogenic Differentiation.

BACKGROUND: Currently, a heterogeneous category of noncoding RNAs (ncRNA) that directly regulate the expression or function of protein-coding genes is shown to have an effect on the fate decision of stem cells. However, the detailed regulatory roles of ncRNAs in myogenic and cardiomyogenic differentiation of mouse C3H10T1/2 mesenchymal stem cells (MSCs) are far from clear. METHODS: In this study, 5-azacytidine- (5-AZA-) treated C3H10T1/2 cells were differentiated into myocyte-like and cardiomyocyte-like cells. Next, ncRNA associated with myogenic and cardiomyogenic differentiation was identified using high-throughput RNA sequencing (RNA-seq) data. Bioinformatics analysis was conducted to identify the differentially expressed ncRNAs and the related signaling pathways. RESULTS: Myotube-like structure was formed after 5-AZA treatment of C3H10T1/2 cells. In addition, myogenic and cardiomyogenic differentiation-related genes like GATA4, cTnt, MyoD, and Desmin were upregulated significantly after the 5-AZA treatment. Totally, 1538 differentially expressed lncRNAs and 3398 differentially expressed mRNAs were identified, including 1175 upregulated and 363 downregulated lncRNAs and 2429 upregulated and 969 downregulated mRNAs. In addition, 46 differentially expressed circRNAs were identified, including 25 upregulated and 21 downregulated circRNAs. Moreover, the differentially expressed mRNAs were enriched into 5 significant pathways, including those for focal adhesion, ECM-receptor interaction, PI3K-AKT signaling pathway, PPAR signaling pathway, and Tyrosine metabolism. CONCLUSIONS: A systematic view of the expression of ncRNAs in myogenic and cardiomyogenic differentiation of MSCs was provided in the study.

Electrohydrodynamic 3D Printing Scaffolds for Repair of Achilles Tendon Defect in Rats.

Tissue engineering (TE) studies for Achilles tendon (AT) defects are a difficult and popular field in orthopedic medical practice. In this study, we applied electrohydrodynamic three-dimensional (3D) printing technology to construct scaffolds made of poly-(ɛ-ɛ-caprolactone) (PCL) and Pluronic F127 (F127) with different mass-volume ratios. The fibers and porous capabilities of the scaffolds were controlled using this technology. We found that F127 improved the hydrophilicity and degradation of PCL in vitro. The PCL scaffolds with 5% F127 were mostly favorable for cell adhesion and growth, suggesting that the scaffolds had good biocompatibility in vitro. Scaffolds with 5% F127 seeded with C3H10T1/2 cells were transplanted into AT defects in rats. A histological analysis indicated that the TE scaffolds were beneficial for the accumulation and arrangement of collagen fibers. Thus, this study provides fundamental experimental data for future clinical applications regarding TE for ATs. Impact statement Electrohydrodynamic three-dimensional (3D) printing can be used to construct tissue-engineered scaffolds with controllable fibers and good porosity. Pluronic-F127 (F127) improved the hydrophilicity and degradation of the poly-(ɛ-ɛ-caprolactone) (PCL), and a better microscale structure was obtained. The scaffolds with 5% F127, with good pore structures, were favorable for C3H10T1/2 cell growth and cellular morphology, indicating that they had good biocompatibility. In vivo transplantation experiments showed that scaffolds with 5% F127 improved the arrangement of collagen fibers, encouraging their potential application in the construction of future tissue-engineered tendons.

TiO2 Nanoparticles Caused DNA Damage in Lung and Extra-Pulmonary Organs Through ROS-Activated FOXO3a Signaling Pathway After Intratracheal Administration in Rats.

INTRODUCTION: Because of the increased production and application of manufactured Nano-TiO2 in the past several years, it is important to investigate its potential hazards. TiO2 is classified by IARC as a possible human carcinogen; however, the potential mechanism of carcinogenesis has not been studied clearly. The present study aimed to investigate the mechanism of DNA damage in rat lung and extra-pulmonary organs caused by TiO2nanoparticles. METHODS: In the present study, SD rats were exposed to Nano-TiO2 by intratracheal injection at a dose of 0, 0.2, or 1 g/kg body weight. The titanium levels in tissues were detected by ICP-MS. Western blot was used to detect the protein expression levels. The DNA damage and oxidative stress were detected by comet assay and ROS, MDA, SOD, and GSH-Px levels, respectively. RESULTS: The titanium levels of the 1 g/kg group on day-3 and day-7 were significantly increased in liver and kidney as well as significantly decreased in lung compared to day-1. ROS and MDA levels were statistically increased, whereas SOD and GSH-Px levels were statistically decreased in tissues of rats in dose-dependent manners after Nano-TiO2 treatment. PI3K, p-AKT/AKT, and p-FOXO3a/FOXO3a in lung, liver, and kidney activated in dose-dependent manners. The levels of DNA damage in liver, kidney, and lung in each Nano-TiO2 treatment group were significantly increased and could not recover within 7 days. GADD45α, ChK2, and XRCC1 in liver, kidney, and lung of rats exposed to Nano-TiO2 statistically increased, which triggered DNA repair. CONCLUSION: This work demonstrated that Ti could deposit in lung and enter extra-pulmonary organs of rats and cause oxidative stress, then trigger DNA damage through activating the PI3K-AKT-FOXO3a pathway and then promoting GADD45α, ChK2, and XRCC1 to process the DNA repair.

Ambient PM2.5 caused cardiac dysfunction through FoxO1-targeted cardiac hypertrophy and macrophage-activated fibrosis in mice.

Plenty of epidemiological evidences have shown that ambient particulate matter (PM2.5) exposure increased the prevalence of cardiovascular disease, but the potential mechanism has not been known clearly. We established mice models by ambient PM2.5 exposure system to explore the adverse effects of PM2.5 on cardiac function in mice. Forty-eight C57BL/6 mice were randomly divided into 3 groups and exposed to filtered air (FA), unfiltered air (UA) and concentrated PM2.5 air (CA) for 8 or 16 weeks, 6 hours per day, 7 days per week, respectively. The changes of cardiac structure and function, histological analysis and related mechanism were investigated. The main manifestations of cardiac structure were cardiac hypertrophy and fibrosis in a dose- and time-dependent manner after PM2.5 exposure, which led to the decrease of cardiac systolic function. Cardiac hypertrophy in mice might be regulated by PI3K/Akt/FoxO1 signal. Cardiac fibrosis might be attributed to inflammatory infiltration caused by macrophage activation. Consequently, our data indicated that cardiac hypertrophy and fibrosis might be important factors of PM2.5-induced cardiac dysfunction in mice.

Pulmonary toxicities from a 90-day chronic inhalation study with carbon black nanoparticles in rats related to the systemical immune effects.

Background: Recent years, there occurs heavy haze pollution in northern China during wintertime. The potential influence of airborne particulate matter (PM) on human health attracts great concern. The fuel-derived PM in the inhalable size range is dominated by aggregates of nanoparticles of Carbon black (CB). However, there are still lack of evidences especially regarding long-term exposure to explain the chronic effects of nanoscaled CB and the relative mechanism. Purpose: The objective of this study was to identify the potential mechanism of chronic effects of nanoscale CB. The systemic toxicity, immune suppression or activity and local toxicity were evaluated. Methods: 32 rats were divided into 2 groups: 30 mg/m3 CB exposure (nose only, 90 d, 6h/d) and control (clean air). Half of rats were scarified after exposure and another half of rats recovered for 14 days. Eight rats in each group were executed the lung function tests using a ventilated bias flow whole body plethysmograph (WBP). SDS-PAGE protocol was used to detect the deposition and retention of CB in lung of rats. HE staining was used to observe the changes of histopathology. Cell apoptosis was examined by TUNEL assay or flow cytometry. The levels of IL-6, IL-8, IL-17 and TNF-α in serum and lung tissue were evaluated with commercially available ELISA kit. The peripheral blood cell counts were detected by Auto 5-diff hematology analyzer. Results: The lung burden of CB was 16 mg in lung of rats after a 90-day exposure by MPPD. Fourteen percentages of the amount of CB accumulated at the end of the exposure period was cleared from the lung during the 14 dys recovery period. The lung function was significantly decreased and could not recover after a short time recovery. The fibroblasts and granuloma formation were found in lung. The levels of apoptosis and DNA damages were significantly increased in lung cells after CB inhalation. The cytokines levels in lung but not in serum were significantly increased in CB exposure group. The cell counts of WBC, monocytes and neutrophils had 1.72, 3.13, and 2.73-fold increases after CB exposure, respectively. The percentages of CD4+ lymphocytes and the rates of CD4+/CD8+ were statistically increased after CB exposure. The stimulation indexes of the peripheral blood lymphocytes were significantly decreased after CB exposure. In the CB exposure group, the disrupted histomorphology of thymus and spleen were found as well as the early apoptotic thymocytes had a 2.36-fold increase. Conclusion: CB induced the localized or direct toxicity and systemic immune toxicity. The direct and systemic immune responses had a combined effect on the lung damages caused by CB.