Tannic Acid-Modified Decellularized Tendon Scaffold with Antioxidant and Anti-Inflammatory Activities for Tendon Regeneration.

Tendon regeneration is greatly influenced by the oxidant and the inflammatory microenvironment. Persistent inflammation during the tendon repair can cause matrix degradation, tendon adhesion, and excessive accumulation of reactive oxygen species (ROS), while excessive ROS affect extracellular matrix remodeling and tendon integration. Herein, we used tannic acid (TA) to modify a decellularized tendon slice (DTS) to fabricate a functional scaffold (DTS-TA) with antioxidant and anti-inflammatory properties for tendon repair. The characterizations and cytocompatibility of the scaffolds were examined in vitro. The antioxidant and anti-inflammatory activities of the scaffold were evaluated in vitro and further studied in vivo using a subcutaneous implantation model. It was found that the modified DTS combined with TA via hydrogen bonds and covalent bonds, and the hydrophilicity, thermal stability, biodegradability, and mechanical characteristics of the scaffold were significantly improved. Afterward, the results demonstrated that DTS-TA could effectively reduce inflammation by increasing the M2/M1 macrophage ratio and interleukin-4 (IL-4) expression, decreasing the secretion of interleukin-6 (IL-6) and interleukin-1ß (IL-1ß), as well as scavenging excessive ROS in vitro and in vivo. In summary, DTS modified with TA provides a potential versatile scaffold for tendon regeneration.

Decellularized tendon scaffolds loaded with collagen targeted extracellular vesicles from tendon-derived stem cells facilitate tendon regeneration.

Stem cell-based treatment of tendon injuries remains to have some inherent issues. Extracellular vesicles derived from stem cells have shown promising achievements in tendon regeneration, though their retention in vivo is low. This study reports on the use of a collagen binding domain (CBD) to bind extracellular vesicles, obtained from tendon-derived stem cells (TDSCs), to collagen. CBD-extracellular vesicles (CBD-EVs) were coupled to decellularized bovine tendon sheets (DBTS) to fabricate a bio-functionalized scaffold (CBD-EVs-DBTS). Our results show that thus obtained bio-functionalized scaffolds facilitate the proliferation, migration and tenogenic differentiation of stem cells in vitro. Furthermore, the scaffolds promote endogenous stem cell recruitment to the defects, facilitate collagen deposition and improve the biomechanics of injured tendons, thus resulting in functional regeneration of tendons.

Relationship between lung injury extent and phenotype manifested in non-contrast CT and cardiac injury during acute stage of COVID-19.

PURPOSE: This study evaluated the diagnostic values of the extent of lung injury manifested in non-contrast enhanced CT (NCCT) images, the inflammatory and immunological biomarkers C-reactive protein (CRP) and lymphocyte for detecting acute cardiac injury (ACI) in patients with COVID-19. The correlations between the NCCT-derived parameters and arterial blood oxygen level were also investigated. METHODS: NCCT lung images and blood tests were obtained in 143 patients with COVID-19 in approximately two weeks after symptom onset, and arterial blood gas measurement was also acquired in 113 (79%) patients. The diagnostic values of normal, moderately and severely abnormal lung parenchyma volume relative to the whole lungs (RVNP, RVMAP, RVSAP, respectively) measured from NCCT images for detecting the heart injury confirmed with high-sensitivity troponin I assay was determined. RESULTS: RVNP, RVMAP and RVSAP exhibited similar accuracy for detecting ACI in COVID-19 patients. RVNP was significantly lower while both RVMAP and RVSAP were significantly higher in the patients with ACI. All of the NCCT-derived parameters exhibited poor linear and non-linear correlations with PaO2 and SaO2. The patients with ACI had a significantly higher CRP level but a lower lymphocyte level compared to the patients without ACI. Combining one of these two biomarkers with any of the three NCCT-derived parameter further improved the accuracy for predicting ACI in patients with COVID-19. CONCLUSION: The NCCT-delineated normal and abnormal lung parenchmyma tissues were statistically significant predictors of ACI in patients with COVID-19, but both exhibited poor correlations with the arterial blood oxygen level. The incremental diagnostic values of lymphocyte and CRP suggested viral infection and inflammation were closely related to the heart injury during the acute stage of COVID-19.

[Characteristics and Removal Mechanism of an Electro-Hybrid Ozonation-Coagulation System in the Treatment of Organic Matters].

To improve the removal efficiency of dissolved organic matter in wastewater treatment plant (WWTP) effluent, electro-hybrid ozonation-coagulation (E-HOC) is proposed and the treatment characteristics and removal mechanism for WWTP effluent and ibuprofen (IBP) are investigated. The E-HOC process has a better removal effect on dissolved organic matter in WWTP effluent, achieving 46.4%, 20.0%, 19.4%, 36.1%, and 49.7% higher removal than EC, ozonation, pre-ozonation-EC, electrocoagulation-ozonation, and chemical coagulation, respectively. To determine the mechanism of the E-HOC process, quenching experiments and electron paramagnetic resonance (EPR) were conducted, which confirmed that metal coagulants can be used as a catalyst to effectively increase the generation of the hydroxyl radical (·OH). Synergistic effects between ozone and the coagulants (SOC) were also found to be involved. Fourier-transform infrared spectroscopy (FT-IR) illustrated that the surface hydroxyl groups of the coagulant (hydrolyzed species produced by Al anode electrolysis) were the active sites for the generation of·OH in the SOC reaction. Based on a kinetics analysis of organic matter removal in the E-HOC system, SOC effects and ozonation played dominant roles in the E-HOC process. Additionally, the SOC created a new pathway for·OH formation.

[Study on UHPLC fingerprint and determination of eight phenolic components of Tetrastigma hemsleyanum leaves].

A novel method combining ultra-high performance liquid chromatography (UHPLC) fingerprint and simultaneous quantitative analysis of eight phenolic components was developed and validated for quality evaluation of Tetrastigma hemsleyanum leaves. For fingerprint analysis, 15 peaks were selected as the common peaks to evaluate the similarities among 41 batches of T. hemsleyanum leaves collected from different regions. Additionally, simultaneous quantification of eight markers, including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, isoorientin, orientin, vitexin-2-O-rhamnoside,vitexin and isovitexin, was performed and the obtained data demonstrated that our method has achieved desired linearity, precision and accuracy. Clustering statistical analysis was further application in T. hemsleyanum leaves from different regions. The results indicated that new approach conbine ultra-high performance liquid chromatography (UHPLC) fingerprint and simultaneous quantitative analysis of eight phenolic components was applicable in quality control of T. hemsleyanum leaves.