Functional biomaterials for modulating the dysfunctional pathological microenvironment of spinal cord injury.

Spinal cord injury (SCI) often results in irreversible loss of sensory and motor functions, and most SCIs are incurable with current medical practice. One of the hardest challenges in treating SCI is the development of a dysfunctional pathological microenvironment, which mainly comprises excessive inflammation, deposition of inhibitory molecules, neurotrophic factor deprivation, glial scar formation, and imbalance of vascular function. To overcome this challenge, implantation of functional biomaterials at the injury site has been regarded as a potential treatment for modulating the dysfunctional microenvironment to support axon regeneration, remyelination at injury site, and functional recovery after SCI. This review summarizes characteristics of dysfunctional pathological microenvironment and recent advances in biomaterials as well as the technologies used to modulate inflammatory microenvironment, regulate inhibitory microenvironment, and reshape revascularization microenvironment. Moreover, technological limitations, challenges, and future prospects of functional biomaterials to promote efficient repair of SCI are also discussed. This review will aid further understanding and development of functional biomaterials to regulate pathological SCI microenvironment.

Bionic Bilayer Scaffold for Synchronous Hyperthermia Therapy of Orthotopic Osteosarcoma and Osteochondral Regeneration.

Large osseous void, postsurgical neoplastic recurrence, and slow bone-cartilage repair rate raise an imperative need to develop functional scaffold in clinical osteosarcoma treatment. Herein, a bionic bilayer scaffold constituting croconaine dye-polyethylene glycol@sodium alginate hydrogel and poly(l-lactide)/hydroxyapatite polymer matrix is fabricated to simultaneously achieve a highly efficient killing of osteosarcoma and an accelerated osteochondral regeneration. First, biomimetic osteochondral structure along with adequate interfacial interaction of the bilayer scaffold provide a structural reinforcement for transverse osseointegration and osteochondral regeneration, as evidenced by upregulated specific expressions of collagen type-I, osteopontin, and runt-related transcription factor 2. Meanwhile, thermal ablation of the synthesized nanoparticles and mitochondrial dysfunction caused by continuously released hydroxyapatite induce residual tumor necrosis synergistically. To validate the capabilities of inhibiting tumor growth and promoting osteochondral regeneration of our proposed scaffold, a novel orthotopic osteosarcoma model simulating clinical treatment scenarios of bone tumors is established on rats. Based on amounts of in vitro and in vivo results, an effective killing of osteosarcoma and a suitable osteal-microenvironment modulation of such bionic bilayer composite scaffold are achieved, which provides insightful implications for photonic hyperthermia therapy against osteosarcoma and following osseous tissue regeneration.

Targeting Nanomotor with Near-Infrared/Ultrasound Triggered-Transformation for Polystage-Propelled Cascade Thrombolysis and Multimodal Imaging Diagnosis.

Nowadays, cardiovascular and cerebrovascular diseases caused by venous thromboembolism become main causes of mortality around the world. The current thrombolytic strategies in clinics are confined primarily due to poor penetration of nanoplatforms, limited thrombolytic efficiency, and extremely-low imaging accuracy. Herein, a novel nanomotor (NM) is engineered by combining iron oxide/perfluorohexane (PFH)/urokinase (UK) into liposome nanovesicle, which exhibits near-infrared/ultrasound (NIR/US) triggered transformation, achieves non-invasive vein thrombolysis, and realizes multimodal imaging diagnosis altogether. Interestingly, a three-step propelled cascade thrombolytic therapy is revealed from such intelligent NM. First, the NM is effectively herded at the thrombus site under guidance of a magnetic field. Afterwards, stimulations of NIR/US propel phase transition of PFH, which intensifies penetration of the NM toward deep thrombus dependent on cavitation effect. Ultimately, UK is released from the collapsed NM and achieves pharmaceutical thrombolysis in a synergistic way. After an intravenous injection of NM in vivo, the whole thrombolytic process is monitored in real-time through multimodal photoacoustic, ultrasonic, and color Doppler ultrasonic imagings. Overall, such advanced nanoplatform provides a brand-new strategy for time-critical vein thrombolytic therapy through efficient thrombolysis and multimodal imaging diagnosis.

Circulating mir-199-3p screens the onset of type 2 diabetes mellitus and the complication of coronary heart disease and predicts the occurrence of major adverse cardiovascular events.

BACKGROUND: Coronary heart disease (CHD) is a major complication of type 2 diabetes mellitus (T2DM), which causes an adverse prognosis. There is an urgent need to explore effective biomarkers to evaluate the patients' adverse outcomes. OBJECTIVE: This study aimed to identify a novel indicator for screening T2DM and T2DM-CHD and predicting adverse prognosis. MATERIALS AND METHODS: The study enrolled 52 healthy individuals, 85 T2DM patients, and 97 T2DM patients combined with CHD. Serum miR-199-3p levels in all study subjects were detected with PCR, and its diagnostic significance was evaluated by receiver operating curve (ROC) analysis. The involvement of miR-199-3p in disease development was assessed by the Chi-square test, and the logistic regression analysis was performed to estimate the risk factor for major adverse cardiovascular events (MACE) in T2DM-CHD patients. RESULTS: Significant downregulation of miR-199-3p was observed in the serum of both T2DM and T2DM-CHD patients, which discriminated patients from healthy individuals and distinguished T2DM and T2DM-CHD patients. Reduced serum miR-199-3p was associated with the increasing blood glucose, glycated hemoglobin (HbA1c), and homeostasis model assessment-insulin resistance index (HOMA-IR) of T2DM patients and the increasing triglycerides (TG), low-density lipoprotein (LDL), fibrinogen, and total cholesterol (TC) and decreasing high-density lipoprotein (HDL) of T2DM-CHD patients. miR-199-3p was also identified as a biomarker predicting the occurrence of MACE. CONCLUSION: Downregulated miR-199-3p could screen the onset of T2DM and its complication with CHD. Reduced serum miR-199-3p was associated with the severe development of T2DM and T2DM-CHD and predicted the adverse outcomes of T2DM-CHD patients.

Global, Regional, and National Advances Toward the Management of Rheumatic Heart Disease Based on the Global Burden of Disease Study 2019.

Background Population growth, aging, and major alterations in epidemiologic trends inadvertently modulate the status of rheumatic heart disease (RHD) epidemiology. This investigation predicted RHD burden pattern and temporal trends to provide epidemiologic evidence. Methods and Results Prevalence, mortality, and disability-adjusted life-years data for RHD were obtained from the GBD (Global Burden of Disease) study. We performed decomposition analysis and frontier analysis to assess variations and burden in RHD from 1990 to 2019. In 2019, there were >40.50 million RHD cases worldwide, along with nearly 0.31 million RHD-related deaths and 10.67 million years of healthy life lost to RHD. The RHD burden was commonly concentrated within lower sociodemographic index regions and countries. RHD primarily affects women (22.52 million cases in 2019), and the largest age-specific prevalence rate was at 25 to 29 years in women and 20 to 24 years in men. Multiple reports demonstrated prominent downregulation of RHD-related mortality and disability-adjusted life-years at the global, regional, and national levels. Decomposition analysis revealed that the observed improvements in RHD burden were primarily due to epidemiological alteration; however, it was negatively affected by population growth and aging. Frontier analysis revealed that the age-standardized prevalence rates were negatively linked to sociodemographic index, whereas Somalia and Burkina Faso, with lower sociodemographic index, showed the lowest overall difference from the frontier boundaries of mortality and disability-adjusted life-years. Conclusions RHD remains a major global public health issue. Countries such as Somalia and Burkina Faso are particularly successful in managing adverse outcomes from RHD and may serve as a template for other countries.

Dual-Modal Imaging and Synergistic Spinal Tumor Therapy Enabled by Hierarchical-Structured Nanofibers with Cascade Release and Postoperative Anti-adhesion.

Most treatments for spinal cancer are accompanied by serious side effects including subsequent tumor recurrence, spinal cord compression, and tissue adhesion, thus a highly effective treatment is crucial for preserving spinal and neurological functionalities. Herein, trilayered electrospun doxorubicin@bovine serum albumin/poly(ε-caprolactone)/manganese dioxide (DOX@BSA/PCL/MnO2) nanofibers with excellent antiadhesion ability, dual glutathione/hydrogen peroxide (GSH/H2O2) responsiveness, and cascade release of Mn2+/DOX was fabricated for realizing an efficient spinal tumor therapy. In detail, Fenton-like reactions between MnO2 in the fibers outermost layer and intra-/extracellular glutathione within tumors promoted the first-order release of Mn2+. Then, sustained release of DOX from the fibers' core layer occurred along with the infiltration of degradation fluid. Such release behavior avoided toxic side effects of drugs, regulated inflammatory tumor microenvironment, amplified tumor elimination efficiency through synergistic chemo-/chemodynamic therapies, and inhibited recurrence of spinal tumors. More interestingly, magnetic resonance and photoacoustic dual-modal imaging enabled visualizations of tumor therapy and material degradation in vivo, achieving rapid pathological analysis and diagnosis. On the whole, such versatile hierarchical-structured nanofibers provided a reference for rapid and potent theranostic of spinal cancer in future clinical translations.

Osteoimmunity-Regulating Biomimetically Hierarchical Scaffold for Augmented Bone Regeneration.

Engineering a proper immune response following biomaterial implantation is essential to bone tissue regeneration. Herein, a biomimetically hierarchical scaffold composed of deferoxamine@poly(ε-caprolactone) nanoparticles (DFO@PCL NPs), manganese carbonyl (MnCO) nanosheets, gelatin methacryloyl hydrogel, and a polylactide/hydroxyapatite (HA) matrix is fabricated to augment bone repair by facilitating the balance of the immune system and bone metabolism. First, a 3D printed stiff scaffold with a well-organized gradient structure mimics the cortical and cancellous bone tissues; meanwhile, an inside infusion of a soft hydrogel further endows the scaffold with characteristics of the extracellular matrix. A Fenton-like reaction between MnCO and endogenous hydrogen peroxide generated at the implant-tissue site triggers continuous release of carbon monoxide and Mn2+ , thus significantly lessening inflammatory response by upregulating the M2 phenotype of macrophages, which also secretes vascular endothelial growth factor to induce vascular formation. Through activating the hypoxia-inducible factor-1α pathway, Mn2+ and DFO@PCL NP further promote angiogenesis. Moreover, DFO inhibits osteoclast differentiation and synergistically collaborates with the osteoinductive activity of HA. Based on amounts of data in vitro and in vivo, strong immunomodulatory, intensive angiogenic, weak osteoclastogenic, and superior osteogenic abilities of such an osteoimmunity-regulating scaffold present a profound effect on improving bone regeneration, which puts forward a worthy base and positive enlightenment for large-scale bone defect repair.

Phase-locking dynamics of a 2D VCSEL hexagonal array with an integrated Talbot cavity.

In this paper, phase-locking dynamics of 2D VCSEL hexagonal array with an integrated Talbot cavity are numerically investigated based on rate equations aiming at achieving high brightness output. The processes of wavelength synchronization and phase locking under different fill factors ff and fractional Talbot cavity lengths L were addressed comprehensively. Different supermodes of phase-locked VCSEL array were then analyzed from both near-field and far-field pattern, and proved to be well matched with the results of coupled-mode theory. With appropriate configuration the Talbot-VCSEL system can operate in a full in-phase mode eventually, which is beneficial for determining the parameter interval corresponding to the most expected single narrow-lobe far-field pattern. Furthermore, the simulation results also indicate that, considering the parametric interactions the distribution of optical feedback from the fractional Talbot cavity should be consistent as much as possible to facilitate the realization of phase-locked state. Our study could provide a theoretical support to obtain the full in-phase coupled VCSEL array with high performance.

Stimuli-Responsive Nanoparticles for Controlled Drug Delivery in Synergistic Cancer Immunotherapy.

Cancer immunotherapy has achieved promising clinical progress over the recent years for its potential to treat metastatic tumors and inhibit their recurrences effectively. However, low patient response rates and dose-limiting toxicity remain as major dilemmas for immunotherapy. Stimuli-responsive nanoparticles (srNPs) combined with immunotherapy offer the possibility to amplify anti-tumor immune responses, where the weak acidity, high concentration of glutathione, overexpressions of enzymes, and reactive oxygen species, and external stimuli in tumors act as triggers for controlled drug release. This review highlights the design of srNPs based on tumor microenvironment and/or external stimuli to combine with different anti-tumor drugs, especially the immunoregulatory agents, which eventually realize synergistic immunotherapy of malignant primary or metastatic tumors and acquire a long-term immune memory to prevent tumor recurrence. The authors hope that this review can provide theoretical guidance for the construction and clinical transformation of smart srNPs for controlled drug delivery in synergistic cancer immunotherapy.

A mussel-inspired supramolecular hydrogel with robust tissue anchor for rapid hemostasis of arterial and visceral bleedings.

In recent years, the developed hemostatic technologies are still difficult to be applied to the hemostasis of massive arterial and visceral hemorrhage, owing to their weak hemostatic function, inferior wet tissue adhesion, and low mechanical properties. Herein, a mussel-inspired supramolecular interaction-cross-linked hydrogel with robust mechanical property (308.47 ± 29.20 kPa) and excellent hemostatic efficiency (96.5% ± 2.1%) was constructed as a hemostatic sealant. Typically, we combined chitosan (CS) with silk fibroin (SF) by cross-linking them through tannic acid (TA) to maintain the structural stability of the hydrogel, especially for wet tissue adhesion ability (shear adhesive strength = 29.66 ± 0.36 kPa). Compared with other materials reported previously, the obtained CS/TA/SF hydrogel yielded a lower amount of blood loss and shorter time to hemostasis in various arterial and visceral bleeding models, which could be ascribed to the synergistic effect of wound closure under wet state as well as intrinsic hemostatic activity of CS. As a superior hemostatic sealant, the unique hydrogel proposed in this work can be exploited to offer significant advantages in the acute wound and massive hemorrhage with the restrictive access of therapeutic moieties.