Frontiers in Bioengineering and Biotechnology最新文献

Humerus greater tuberosity (HGT) avulsion fracture is one of the most common types of proximal humerus fractures. The presence of motion and gap lead to the failure of implants, due to the force pulling from the supraspinatus. In this work, electrospinning technology was applied to fabricate PCL-PEG/CS/AST nanofiber with superior biocompatibility and mechanical property. Furthermore, PCL-PEG/CS/AST nanofiber could promote proliferation and osteogenic differentiation of bone mesenchymal stem cells (BMSCs) in vitro. We believe that this work indicates a promising way to promote the union of HGT avulsion fractures by using PCL-PEG/CS/AST nanofiber.

Background: Diabetic peripheral neuropathy (DPN) is a common complication of diabetes. Proactive treatment options remain limited, which is exacerbated by a lack of sensitive and convenient diagnostics, especially early in disease progression or specifically to assess small fiber neuropathy (SFN), the loss of distal small diameter axons that innervate tissues and organs.

Methods: We designed, fabricated, tested, and validated a first-of-its-kind medical diagnostic device for the functional assessment of transdermal small fiber nerve activity. This device, the Detecting Early Neuropathy (DEN), is an electrically conductive needle array designed to record nerve electrical activity in the skin and subdermal tissues, as a feature of a broader theragnostic platform.

Results: DEN recordings were validated across a time course of diet-induced PN in mice, using statistical and computational analyses and compared to other SFN measures. Based on these preclinical mouse data, the device design was adapted to obtain recordings in human with a flexible printed circuit board to mold to the leg or other skin regions. The DEN successfully recorded various types of neural activity in mouse and human, with or without stimulation, including validated action potentials and electromyography signals.

Conclusion: New functional diagnostic tools like DEN offer a promising outlook for patients needing an earlier or more sensitive diagnosis of DPN/SFN, to allow for earlier and more effective treatment options, especially as more become available in the clinic in future years.

Artificially designed, functional nanostructured surfaces, called metasurfaces, are an emerging platform for biosensing. Two major types of metasurface biosensors have been reported: one is based on resonant-wavelength shift and the other is specialized for fluorescence (FL) detection. The all-dielectric metasurfaces that composed of periodic arrays of silicon nanocolumns have a series of optical magnetic-mode resonances, some of which were found to significantly enhance capability for FL detection of diverse target biomolecules, ranging from nucleic acid to antigens and antibodies. Here, we mainly address the recent advances in productive metasurface FL biosensors, provide an overview of the pivotal results, and discuss the future prospects, including artificial-intelligence-driven big data analysis for the next-generation healthcare services.

The number of metal-containing waste streams resulting from electronic end-of life products, metallurgical by-products, and mine tailings to name but a few, is increasing worldwide. In recent decades, the potential to exploit these waste streams as valuable secondary resources to meet the high demand of critical and economically important raw materials has become more prominent. In this review, fundamental principles of bio-based metal recovery technologies are discussed focusing on microbial metabolism-dependent and metabolism-independent mechanisms as sustainable alternatives to conventional chemical metal recovery methods. In contrast to previous reviews which have partially addressed this topic, a special focus will be given on how fundamental principles of bio-based recovery technologies can influence the selectivity and specificity of metal recovery. While conventional methods for metal recovery show benefits in terms of economic affordability, bio-based recovery technologies offer advantages in terms of efficiency and environmentally friendliness. Modifications and adaptations in the processes of biosorption, bioaccumulation and bioelectrochemical systems are highlighted, further emphasizing the application of metal-binding peptides and siderophores to increase selectivity in the recovery of metals. Single metal solutions or mixtures with a low complexity have been the focus of previous studies and reviews, but this does not reflect the nature of complex industrial effluents. Therefore, key challenges that arise when dealing with complex polymetallic solutions are addressed and the focus is set on optimizing bio-based technologies to recover metals efficiently and selectively from bio-leachates or liquid waste streams.

This study evaluated the growth performance of Tetradesmus obliquus and Chlorella vulgaris microalgae cultivated in diluted liquid digestate supplemented with CO₂, comparing their efficiency to that of a conventional synthetic media. The presence of an initial concentration of ammonium of 125 mg N-NH₄ ⁺.L^-1 combined with the continuous injection of 1% v/v CO₂ enhanced the optimal growth responses and bioremediation potential for both strains in 200-mL cultures. In 6-L flat panel reactors, T. obliquus exhibited superior biomass production, achieving a final biomass concentration of 1.29 ± 0.06 g.L^-1, while C. vulgaris reached only 0.36 ± 0.02 g.L^-1. Both strains effectively contributed to the bioremediation of the digestate-based culture media, with up to 100% of N-NH₄ ⁺, 50% of COD, and 55% of P-PO₄ ^3- removals. The high nitrogen levels in the digestate-based medium significantly increased protein content, with 46.21% ± 3.98% dry weight (DW) for T. obliquus and 44.17% ± 2.24% DW for C. vulgaris as compared to the microalgae cultivated in commercial media. Additionally, the metal content of the microalgal biomass was analyzed to assess its potential use as biostimulants in compliance with European regulations. While chromium concentrations slightly exceeded regulatory thresholds in both strains, the levels of other metals remained within permissible limits.

Background: Microfracture drilling is a surgical technique that involves creating multiple perforations in areas of cartilage defects to recruit stem cells from the bone marrow, thereby promoting cartilage regeneration in the knee joint. Increasing the exposed bone marrow surface area (more holes in the same area) can enhance stem cell outflow. However, when the exposed area is large, it may affect the mechanical strength of the bone at the site of the cartilage defect. The purpose of this study is to use the finite element method to analyze the effects of drilling diameter, hole spacing, and drilling depth during microfracture surgery on the stability of the bone structure at the cartilage defect site.

Methods: In this study, a normal knee joint model was selected for solid modeling, and a model of a femoral medial condyle cartilage defect was constructed. Microfracture holes with different diameters (1.0 mm, 2.0 mm, 3.0 mm), depths (10 mm, 30 mm), and spacings (1.0 mm, 2.0 mm, 3.0 mm) were created in the femoral medial condyle cartilage defect model. Using Ansys software, the knee joint's loading conditions in the standing position were simulated, and the structural stability of the model was analyzed. The holes in areas of stress concentration were selected for more detailed mechanical analysis.

Results: The Von Mises stresses for all the drilling parameters did not exceed the yield strength of the bone. Changes in the drilling parameters did not affect the bone structure around the holes. When smaller diameter drilling tools with closer spacing were used, the average maximum Von Mises stress and the average Von Mises stress on the holes were the lowest.

Conclusion: Although the optimal combination of drilling parameters was not determined, this study provides a mechanical reference for the effects of drilling parameters on bone quality. It demonstrates that using smaller diameter drilling tools with closer spacing in areas of the same defect size results in a greater number of holes, with a lesser impact on bone stability. This study provides a mechanical reference for microfracture drilling.

Cancer is a major killer threatening modern human health and a leading cause of death worldwide. Due to the heterogeneity and complexity of cancer, traditional treatments have limited effectiveness. To address this problem, an increasing number of researchers and medical professionals are working to develop new ways to treat cancer. Bacteria have chemotaxis that can target and colonize tumor tissue, as well as activate anti-tumor immune responses, which makes them ideal for biomedical applications. With the rapid development of nanomedicine and synthetic biology technologies, bacteria are extensively used as carriers for drug delivery to treat tumors, which holds the promise of overcoming the limitations of conventional cancer treatment regimens. This paper summarizes examples of anti-cancer drugs delivered by bacterial carriers, and their strengths and weaknesses. Further, we emphasize the promise of bacterial carrier delivery systems in clinical translation.

Fermentation of ginseng extract is limited by the low concentration of compound K (CK), a bioactive ginsenoside. In this study, a novel approach combining Aspergillus tubingensis fermentation with Aspergillus niger cellulase conversion was used to enhance CK production from high concentrations of American ginseng extract (AGE). The reaction conditions, including the feeding rate and concentrations of carbon source, enzyme type, AGE and enzyme concentrations, temperature, pH, and timing of enzyme addition, were optimized. Under optimized conditions, this combined method achieved an enhanced CK production of 8.06 g/L (13.0 mM) after 168 h, with a productivity of 48 mg/L/h. This approach led to a 2.0-fold increase in concentration and a 1.7-fold increase in productivity when compared with traditional fermentation using the same strain. The findings of this study demonstrate the synergistic effect of combining fermentation with enzyme conversion to improve CK production.

Introduction: Artificial vascular scaffolds can mimic the structure of natural blood vessels and replace the damaged vessels by implanting them at the injury site to perform the corresponding functions. Electrospinning technology can perfectly combine biological signals and topographical cues to synergistically induce directed cell migration and growth.

Methods: In this study, poly (caprolactone) (PCL) nanofibers, PCL nanofibers uniformly coated with the extracellular matrix derived from endothelial cells (ECd), and bi-directional linear gradient ECd-coated PCL nanofibers were prepared by electrospinning and electrospray techniques to evaluate their effects on the proliferation and migration of Human umbilical vein endothelial cells (HUVECs) and rapid endothelialization.

Results: The results showed that HUVECs could successfully adhere to the surface of these three nanofibers and maintain high viability. The migration results indicated that the bidirectional linear gradient coating could accelerate the migration of HUVECs and the endothelialization process. On this basis, three types of bionic vascular scaffolds, including PCL vascular scaffold, uniform ECd-coated PCL vascular scaffold, and bi-directional linear gradient ECd-coated PCL vascular scaffold, were further prepared. The results showed that the topology and biological signal of the bi-directional linear gradient ECd-coated PCL vascular scaffold synergistically promoted the migration of HUVECs more effectively.

Discussion: This provides a new way to clinically promote the structural and functional recovery of damaged vessels and develop personalized or universal artificial vascular scaffolds, which is of great importance in cardiovascular regenerative medicine.

Myocardial infarction (MI) is the leading cause of morbidity and mortality worldwide. Curcumin has been observed to significantly reduce pathological processes associated with MI. Its clinical application is limited due to its low bioavailability, rapid degradation, and poor solubility. Advancements in nanotechnology can be used to enhance its therapeutic potentials in MI. Curcumin nano-formulation enhances its solubility, stability, and bioavailability, allowing more precise delivery to ischemic cardiac tissue. Curcumin nanoparticles have been observed to successfully reduce infarct size, maintain heart function by modulating essential molecular pathways in MI. Its liposomal formulations provide sustained release and higher tissue penetration with improved pharmacokinetics and enhanced therapeutic efficacy. Preclinical studies revealed that nanocurcumin drastically lower oxidative stress indicators, inflammatory cytokines, and cardiac damage. Micelles composed of polymers have demonstrated high biocompatibility and targeting capabilities with increased cardio-protective effects. Research and clinical trials are essential for comprehensive analysis and efficacy of curcumin-based nano-therapeutics in cardiovascular condition and lowering risk of MI.