Mechanisms Of Regeneration Research Articles

Designable Electrochemiluminescence Patterning for Renewable and Enhanced Bioimaging

Electrochemical imaging enables an in‐depth analysis of the interface heterogeneity and reaction kinetics of single entities. However, electrode passivation during electrochemical reactions decreases the active sites and harms the long‐term stability. Here, we introduce a method using laser‐induced photothermal effects to restore the electrochemical activity, which is particularly displayed as enhanced micrometric patterns in electrochemiluminescence (ECL) microscopy. By co‐localization characterization and X‐ray photoelectron spectroscopy, the mechanism of active site regeneration is validated as the removal of the oxide film for restoring the local surface ECL reactivity under laser irradiation. The surface‐confined and voltage‐dependent features of ECL allows for easy pattern erasure and rewriting, and it shows good reversibility and anti‐counterfeiting potential. This approach overcomes the passivation processes, evidently improves the image quality of single biological entities including Shewanella bacteria and cells, and makes the subtle contour structures more distinct. The renewable electrode interface also enhances the ECL signal of model bead‐based bioassays. This approach not only showcases precise control in fabricating micron patterns but also holds promise for enhancing the sensitivity in electrochemical immunoassays and bioimaging.

Designable Electrochemiluminescence Patterning for Renewable and Enhanced Bioimaging

Electrochemical imaging enables an in‐depth analysis of the interface heterogeneity and reaction kinetics of single entities. However, electrode passivation during electrochemical reactions decreases the active sites and harms the long‐term stability. Here, we introduce a method using laser‐induced photothermal effects to restore the electrochemical activity, which is particularly displayed as enhanced micrometric patterns in electrochemiluminescence (ECL) microscopy. By co‐localization characterization and X‐ray photoelectron spectroscopy, the mechanism of active site regeneration is validated as the removal of the oxide film for restoring the local surface ECL reactivity under laser irradiation. The surface‐confined and voltage‐dependent features of ECL allows for easy pattern erasure and rewriting, and it shows good reversibility and anti‐counterfeiting potential. This approach overcomes the passivation processes, evidently improves the image quality of single biological entities including Shewanella bacteria and cells, and makes the subtle contour structures more distinct. The renewable electrode interface also enhances the ECL signal of model bead‐based bioassays. This approach not only showcases precise control in fabricating micron patterns but also holds promise for enhancing the sensitivity in electrochemical immunoassays and bioimaging.

Unraveling the Nexus: The Role of Collapsin Response Mediator Protein 2 Phosphorylation in Neurodegeneration and Neuroregeneration

AbstractNeurodegenerative disease characterized by the progressive damage of the nervous system, and neuropathies caused by the neuronal injury are both led to substantial impairments in neural function and quality of life among geriatric populations. Recovery from nerve damage and neurodegenerative diseases present a significant challenge, as the central nervous system (CNS) has limited capacity for self-repair. Investigating mechanism of neurodegeneration and regeneration is essential for advancing our understanding and development of effective therapies for nerve damage and degenerative conditions, which can significantly enhance patient outcomes. Collapsin response mediator protein 2 (CRMP2) was first identified as a key mediator of axonal growth and guidance is essential for neurogenesis and neuroregeneration. Phosphorylation as a primary modification approach of CRMP2 facilitates its involvement in numerous physiological processes, including axonal guidance, neuroplasticity, and cytoskeleton dynamics. Prior research on CRMP2 phosphorylation has elucidated its involvement in the mechanisms of neurodegenerative diseases and nerve damage. Pharmacological and genetic interventions that alter CRMP2 phosphorylation have shown the potential to influence neurodegenerative diseases and promote nerve regeneration. Even with decades of research delving into the intricacies of CRMP2 phosphorylation, there remains a scarcity of comprehensive literature reviews addressing this topic. This absence of synthesis and integration of findings hampers the field’s progress by preventing a holistic understanding of CRMP2’s implications in neurobiology, thereby impeding potential advancements in clinical treatments and interventions. This review intends to compile investigations focused on the role of CRMP2 phosphorylation in both neurodegenerative disease models and injury models to summarizing impacts and offer novel insight for clinical therapies.

THE ROLE OF INTRACELLULAR SIGNALING PATHWAYS IN THE DEVELOPMENT OF TROPHIC PATHOLOGIES OF THE LOWER EXTREMITIES AND THEIR REGENERATION UNDER TYPE 2 DIABETES (PART 1)

Introduction. This review article addresses the critical issue of the development and regeneration of chronic trophic ulcers in the context of type 2 diabetes. This pathological process is associated with inhibited cell proliferation, impaired differentiation of various cell types, and disrupted mechanisms that regulate cell death. An analysis of recent scientific literature also highlights the involvement of key intracellular signaling pathways in the development of chronic ulcerative pathologies of the lower extremities, as observed in both experimental animal models and patients with type II diabetes. Despite advancements, this issue remains insufficiently explored in both theory and practice, underscoring its ongoing relevance. The aim of this study is to identify the roles of key signaling pathways—transforming growth factor β (TGF-β), phosphatidylinositol 3-kinase/serine-threonine kinase (PI3K/Akt), and Wnt/β-catenin—in the inflammatory response, regenerative mechanisms, and healing processes of soft tissue damage and trophic ulcers in experimental animals and patients with type II diabetes. Materials and Methods. This study is based on an analysis of current scientific literature that addresses this topic. Results. It has been found out that changes in the content and activity of key molecules of signaling pathways lead to disruption of carbohydrate homeostasis and the occurrence of structural and functional dysfunction in damaged tissues against the background of type II diabetes. These include TGF-β, PI3K, Akt and β-catenin. Analysis of experimental data demonstrated that both under the conditions of type II diabetes development and in the occurrence of chronic ulcers of the lower extremities, against the background of this endocrine disease, there is an increase in the level of TGF-β. At the same time the activity of the PI3K/Akt signaling pathway in the above-mentioned studied groups was reduced. The relationship between the development of type II diabetes and the Wnt/β-catenin signaling pathway has been established. Suppression of its activity was accompanied by impaired regeneration of chronic trophic ulcers in type II diabetes. Conclusion. Thus, the mechanism of type II diabetes and chronic peptic ulcer disease, in the same pathology, is associated with a impaired activity of signaling cascades. This concerns the following cellular systems such as TGF-β, PI3K/Akt and Wnt/β-catenin. They can be considered as potential therapeutic targets for the development of newest methods for the treatment of chronic trophic ulcers in type II diabetes in order to accelerate the recovery process of volumetric tissue damage of the lower extremities.

A 4D time-lapse morphometry method to quantify bone formation and resorption during distraction osteogenesis.

Distraction osteogenesis (DO) is widely utilized for treating limb length discrepancy, nonunion, bone deformities and defects. This study sought to develop a 4D time-lapse morphometry method to quantify bone formation and resorption in mouse femur during DO based on image registration of longitudinal in vivo micro-CT scans. Female C57BL/6 mice (n = 7) underwent osteotomy, followed by 5 days of latency, 10 days of distraction and 35 days of consolidation. The mice were scanned with micro-CT at Days 5, 15, 25, 35, 45, and 50. Histological sectioning and Movat Pentachrome straining were performed at Day 50. After registration of two consecutive micro-CT images of the same bone (day x and day y), the spatially- and temporally-linked sequences of formation, resorption and quiescent bones at the distraction gap were identified and bone formation and resorption rates (BFRdayx-y and BRRdayx-y) were calculated. The overall percentage error of the registration method was 2.98% ± 0.89% and there was a strong correlation between histologically-measured bone area fraction and micro-CT-determined bone volume fraction at Day 50 (r = 0.89, p < 0.05). The 4D time-lapse morphometry indicated a rapid bone formation during the first 10 days of the consolidation phase (BFRday15-25 = 0.14 ± 0.05 mm3/day), followed by callus reshaping via equivalent bone formation and resorption rates. The 4D time-lapse morphometry method developed in this study allows for a continuous quantitative monitoring of the dynamic process of bone formation and resorption following distraction, which may offer a better understanding of the mechanism for mechano-regulated bone regeneration and aid for development of new treatment strategies of DO.

A self-regenerative heat pump based on a dual-functional relaxor ferroelectric polymer.

Electrocaloric (EC) cooling presents a promising approach to efficient and compact solid-state heat pumps. However, reported EC coolers have complex architectures and limited cooling temperature lift. In this work, we introduce a self-regenerative heat pump (SRHP) using a cascade of EC polymer film stacks, which have electrostrictive actuations in response to an electric field that are directed to realize efficient heat transfer, eliminating the need for additional transportive or regenerative mechanisms. The SRHP demonstrates a cooling of 8.8 kelvin below ambient temperature in 30 seconds and delivers a maximum specific cooling power of 1.52 watts per gram. The temperature lift of the SRHP is 14.2 kelvin. These results underscore the potential of the compact solid-state cooling mechanism to address the increasing need for localized thermal management.

Molecular model and its evolution during secondary regeneration of asphalt based on molecular dynamics

With the use of recycled asphalt pavement, numerous recycled pavements will suffer from damages which needs to be regenerated for the second time (i.e. secondary regeneration). The mechanism and impact of secondary regeneration may diverge from those observed during primary regeneration. To study the aging and regeneration mechanism of secondary regenerated asphalt, the molecule models of regenerant and asphalts under different aging states were established through the molecular dynamics (MD). The double-layer diffusion models were constructed to examine the fusion behavior of new and aged asphalts. Based on this, the dynamic viscosity, rotational viscosity, bulk modulus, and shear modulus of secondary regenerated asphalt were predicted. The findings indicate that the established molecular models have a strong correlation with real asphalt molecules. During secondary regeneration, the deepening of asphalt aging reduces the fusion velocity and efficiency between aged and new asphalts. The introduction of regenerant can enhance the diffusion velocity between the aged and new asphalts, yet it does not necessarily improve their fusion degree. During the process of secondary regeneration, the shear modulus of secondary aged asphalt can be effectively restored by adding regenerant, but the recovery of dynamic viscosity, rotational viscosity and bulk modulus presents poor trends when compared to the primary regeneration.

The Potential Applications of Stem Cell Conditioned Medium Secretome in Knee Cartilage Regeneration: A Systematic Review

Background: Articular cartilage injuries often result from trauma, genetic predisposition, and degeneration. These injuries lack inherent regeneration mechanisms due to the absence of blood vessels and limited progenitor cell entry. Osteoarthritis is characterized by gradual cartilage deterioration. Mesenchymal stem cells (MSCs), particularly their secretome including exosomes, hold promise as a regenerative therapy. This review explores the application of MSCs and their secretome to address cartilage defects.Methods: This review was conducted based on PRISMA guidelines. Animal model studies focusing on the use of stem cell secretomes for cartilage regeneration were explored. The search, encompassing PubMed, MEDLINE, the Cochrane Library, Scopus, Web of Science, and Science Direct from January 10, 2023, to July 27, 2023, was conducted utilizing Google Chrome as the search engine. Studies with outcomes based on OARSI or ICRS scores, as well as any additional outcomes related to MSC secretome utilization, cartilage regeneration, and proliferation, were included.Results: Our systematic review identified six studies using MSCs in vivo and in vitro. Synovial membrane-derived MSCs significantly enhanced cartilage regeneration by elevating chondrogenic capabilities. Hydrogel-based systems techniques and 3D-printed scaffolds have emerged for innovative delivery. Specific microRNAs, such as miR-92a-3p, have been recognized for enhancing cartilage regeneration. Strategies for the effective targeting of MSC exosomes to the precise cartilage damage site have been explored.Conclusions: The studies demonstrate the potential of MSC-derived secretomes and exosomes for knee cartilage regeneration in animal models. Further research and clinical trials are needed to refine these approaches for practical application.

Tail Tales: What We Have Learned About Regeneration from Xenopus Laevis Tadpoles

This review explores the regenerative capacity of Xenopus laevis, focusing on tail regeneration, as a model to uncover cellular, molecular, and developmental mechanisms underlying tissue repair. X. laevis tadpoles provide unique insights into regenerative biology due to their regeneration-competent and -incompetent stages and ability to regrow complex structures in the tail, including the spinal cord, muscle, and skin, after amputation. The review delves into the roles of key signaling pathways, such as those involving reactive oxygen species (ROS) and signaling molecules like BMPs and FGFs, in orchestrating cellular responses during regeneration. It also examines how mechanotransduction, epigenetic regulation, and metabolic shifts influence tissue restoration. Comparisons of regenerative capacity with other species shed light on the evolutionary loss of regenerative abilities and underscore X. laevis as an invaluable model for understanding the constraints of tissue repair in higher organisms. This comprehensive review synthesizes recent findings, suggesting future directions for exploring regeneration mechanisms, with potential implications for advancing regenerative medicine.

Magnetically oriented nanosheet interlayer for dynamic regeneration in lithium metal batteries

Lithium (Li) metal has been recognized as a promising anode to advance the energy density of current Li-based batteries. However, the growth of the solid-electrolyte interphase (SEI) layer and dendritic Li microstructure pose significant challenges for the long-term operation of Li metal batteries (LMBs). Herein, we propose the utilization of a suspension electrolyte with dispersed magnetically responsive nanosheets whose orientation can be manipulated by an external magnetic field during cell operation for realizing in situ regeneration in LMBs. The regeneration mechanism arises from the redistribution of the ion flux and the formation of an inorganic-rich SEI for uniform and compact Li deposition. With the magnetic-field-induced regeneration process, we show that a Li||Li symmetric cell stably operates for 350 h at 2 mA cm-2 and 2 mA h cm-2, ~5 times that of the cell with the pristine electrolyte. Furthermore, the cycling stability can be significantly extended in the Li||NMC full cell of 3 mA h cm-2, showing a capacity retention of 67% after 500 cycles at 1C. The dynamic Li metal regeneration demonstrated here could bring useful design considerations for reviving the operating cells for achieving high-energy, long-duration battery systems.

Single-cell resolution of intestinal regeneration in pythons without crypts illuminates conserved vertebrate regenerative mechanisms

Canonical models of intestinal regeneration emphasize the critical role of the crypt stem cell niche to generate enterocytes that migrate to villus ends. Burmese pythons possess extreme intestinal regenerative capacity yet lack crypts, thus providing opportunities to identify noncanonical but potentially conserved mechanisms that expand our understanding of regenerative capacity in vertebrates, including humans. Here, we leverage single-nucleus RNA sequencing of fasted and postprandial python small intestine to identify the signaling pathways and cell-cell interactions underlying the python's regenerative response. We find that python intestinal regeneration entails the activation of multiple conserved mechanisms of growth and stress response, including core lipid metabolism pathways and the unfolded protein response in intestinal enterocytes. Our single-cell resolution highlights extensive heterogeneity in mesenchymal cell population signaling and intercellular communication that directs major tissue restructuring and the shift out of a dormant fasted state by activating both embryonic developmental and wound healing pathways. We also identify distinct roles of BEST4+ enterocytes in coordinating key regenerative transitions via NOTCH signaling. Python intestinal regeneration shares key signaling features and molecules with mammalian gastric bypass, indicating that conserved regenerative programs are common to both. Our findings provide different insights into cooperative and conserved regenerative programs and intercellular interactions in vertebrates independent of crypts which have been otherwise obscured in model species where temporal phases of generative growth are limited to embryonic development or recovery from injury.

Epimorphic regeneration of mammalian digit tip

The article presents lecture materials on regeneration mechanisms from the textbook “Lectures on Regenerative Medicine”. An example of epimorphic regeneration in mammals is considered — the cellular mechanisms of tissue restoration of the fingertip after amputation. This model is a relevant object of research, since it allows us to study the mechanisms of both the formation of a specialized temporary structure of the blastema and subsequent morphogenesis, which ends with the full restoration of all amputated tissues.

Shear-driven magnetic buoyancy in the solar tachocline: Dependence of the mean electromotive force on diffusivity and latitude

Abstract The details of the dynamo process that is responsible for driving the solar magnetic activity cycle are still not fully understood. In particular, whilst differential rotation provides a plausible mechanism for the regeneration of the toroidal (azimuthal) component of the large-scale magnetic field, there is ongoing debate regarding the process that is responsible for regenerating the Sun’s large-scale poloidal field. Our aim is to demonstrate that magnetic buoyancy, in the presence of rotation, is capable of producing the necessary regenerative effect. Building upon our previous work, we carry out numerical simulations of a local Cartesian model of the tachocline, consisting of a rotating, fully compressible, electrically conducting fluid with a forced shear flow. An initially weak, vertical magnetic field is sheared into a strong, horizontal magnetic layer that becomes subject to magnetic buoyancy instability. By increasing the Prandtl number we lessen the back reaction of the Lorentz force onto the shear flow, maintaining stronger shear and a more intense magnetic layer. This in turn leads to a more vigorous instability and a much stronger mean electromotive force, which has the potential to significantly influence the evolution of the mean magnetic field. These results are only weakly dependent upon the inclination of the rotation vector, i.e. the latitude of the local Cartesian model. Although further work is needed to confirm this, these results suggest that magnetic buoyancy in the tachocline is a viable poloidal field regeneration mechanism for the solar dynamo.

New "conservative" treatments for Peyronie's disease-real alternatives or expensive pastime?

Conservative treatment of Peyronie's disease (induratio penis plastica, IPP) remains largely unsuccessful despite decades of research, as the exact disease pathogenesis remains unclear. Currently, IPP is understood as abenign, localized, progressive connective tissue disorder of the tunica albuginea, in which repetitive microtrauma triggers an inflammatory process leading to fibrosis formation. The new "conservative" treatment approaches focus on immune-modulatory and regenerative mechanisms, but significant therapeutic success is still lacking. Treatments such as extracorporeal shockwave therapy, platelet-rich plasma (PRP), stem cell therapy, hyaluronic acid, and botulinum toxin are promising theoretical approaches, but their efficacy is often contradictory and they remain disputed and inadequately supported by studies. Research on these therapeutic approaches is often limited by extremely high costs and the regulations for clinical studies according to the Medicines Act, albeit necessary to further evaluate their effectiveness.

Green regeneration and recycling technology for spent graphite in lithium batteries: Biofilm coating-heat treatment repair process

With the explosive growth in graphite demand and the blowout retirement of lithium-ion batteries (LIBs), the recycling of spent graphite (SG) in anode materials has gradually become a hotspot due to its potential for achieving economic and environmental benefits, as well as contributing to the sustainable development of LIBs industry. An innovative green regeneration technology of SG based on bio-cycle leaching is proposed, and its repair and regeneration mechanism is discussed. The results show that bio-cycle leaching can effectively remove and enrich the metal impurities from SG while utilizing the extracellular polymeric substances secreted by strains to mediate and aggregate strong adhesion of strains on the surface, forming a biofilm to coat graphite and smooth its surface. Heat treatment can repair the crystal structure of SG while breaking down the biofilm into amorphous carbon to create a carbon core-shell structure. Under the optimal conditions, the regenerated graphite exhibits electrochemical properties similar to commercial graphite, with the initial charge capacity, initial coulomb efficiency, and cyclic capacity stability after 100 cycles at 0.1 C rate of 329.11 mAh/g, 92.9 %, and 96.4 %, respectively. This study represents a new thinking in SG recycling and contributes to realizing a complete closed-loop LIB recycling process.

Piperazine-Based Mixed Solvents for CO2 Capture in Bubble-Column Scrubbers and Regeneration Heat

This work used piperazine (PZ) as a base solvent, blended individually with five amines, which were monoethanolamine (MEA), secondary amines (DIPAs), tertiary amines (TEAs), stereo amines (AMPs), and diethylenetriamine (DETA), to prepare mixed solvents at the desired concentrations as the test solvents. A continuous bubble-column scrubber with one stage (1 s) was first used for the test. Six parameters were selected, including the type of mixed solvent (A), the ratio of mixed solvents (B), the solvent feed rate (C), the gas flow rate (D), the concentration of the mixed solvents (E), and the liquid temperature (F), each one having five levels. Using the Taguchi experimental design, only 25 runs were required. The outcome data, such as the absorption efficiency (EF), the absorption rate (RA), the overall mass-transfer coefficient (KGa), and the absorption factor (φ), could be determined under steady-state conditions. The optimal mixed solvents were found to be A1 (PZ + MEA) and A2 (PZ + DIPA). The parameter importance and optimal conditions for EF, RA, KGa, and ϕ were determined separately; the verification of all optimal conditions was successful. This analysis found that the importance of the parameters was D &gt; C &gt; A &gt; E &gt; B &gt; F, and the gas flow rate (D) was the most important factor. Subsequently, multiple-stage scrubbers were used to capture CO2. Comparing 1 s and 3 s (three-stage scrubber), EF, RA, KGa, and φ increased by 33%, 29%, 22%, and 38%, respectively. The desorption tests for the four optimal scrubbed solutions, including multiple stages, showed that the heat of regeneration for the three scrubbers was 3.57–8.93 GJ/t, in the temperature range of 110–130 °C, while A2 was the best solvent. Finally, the heat regeneration mechanism was also discussed in this work.

7877 Adipose Depot Differences In Regenerative Properties Of Exosomes Derived From Human Adipose Stem Cells

Abstract Disclosure: M.A. Krause-Hauch: None. R. Patel: None. B. Osborne: None. P. Albear: None. N.A. Patel: None. Many patients struggle with chronic recalcitrant wounds that are the result of delayed healing. Underlying inflammation is one major risk factor for impaired dermal wound healing that may lead to pathologies such as infection and scarring. Adult human adipose stem cells (hASCs) have shown tremendous potential in regenerative medicine. The regenerative potential of hASCs is dependent on secreted bioactive material which is packaged and released in extracellular exosomes. We previously showed that hASC exosomes from the subcutaneous depot (sc) promoted repair in human dermal fibroblasts using in vitro assays. In this study, we evaluated exosomes derived from the omental depot (om) of hASC and compared its efficacy with sc-hASC. Our results show differences in levels of the long noncoding RNA (lncRNA) cargo between om-hASCexo and sc-hASCexo. Next, we evaluated their repair potential in a wound model in vivo. Male and female F344 rats were dorsally wounded via punch biopsy and silicone scaffolding was attached to prevent contraction. The wounds were then either not treated (control) or treated with 50μg om-hASCexo or sc-hASCexo every alternate day when each wound size was measured for 1 week to monitor healing progress. After 7 days, wounds treated with either om-hASCexo and sc-hASCexo closed significantly faster than untreated control wounds. While no difference was observed in closure percentage after 7 days for wounds treated with either om-hASCexo and sc-hASCexo, sc-hASCexo appeared to act faster earlier (1-2 days post wound) in the wound healing process while om-hASCexo acts faster during later stages (2-4 days post wound) of wound healing. The wound tissue was collected for biochemical and histological analysis. qPCR analysis on day 7 revealed that both om-hASCexo and sc-hASCexo treatment resulted in increased levels of Collagen 1 &amp; 3 and MMP9, while levels of TGF-β decreased with treatment. These results indicate that om-hASCexo and sc-hASCexo enhanced the wound healing process while decreasing inflammation of the wound. To determine the differences between om-hASCexo and sc-hASCexo treatments on wound healing pathways, RNAseq was performed. Results show specificity in pathway activation and gene expression between the om-hASCexo and sc-hASCexo treatments. In conclusion, we have demonstrated that the regenerative mechanisms differ between the hASC depots from which exosomes are secreted. At a broader level, this finding may shed light on the body’s organ health and repair processes in normal or disease states. Presentation: 6/3/2024

Comparative proteomic analysis of regenerative mechanisms in mouse retina to identify markers for neuro-regeneration in glaucoma

The retina is part of the central nervous system (CNS). Neurons in the CNS and retinal ganglion cells lack the ability to regenerate axons spontaneously after injury. The intrinsic axonal growth regulators, their interaction and roles that enable or inhibit axon growth are still largely unknown. This study endeavored to characterize the molecular characteristics under neurodegenerative and regenerative conditions. Data-Independent Acquisition Mass Spectrometry was used to map the comprehensive proteome of the regenerative retina from 14-day-old mice (Reg-P14) and adult mice after lens injury (Reg-LI) both showing regrowing axons in vitro, untreated adult mice, and retina from adult mice subjected to two weeks of elevated intraocular pressure showing degeneration. A total of 5750 proteins were identified (false discovery rate < 1%). Proteins identified in both Reg-P14 and Reg-LI groups were correlated to thyroid hormone, Notch, Wnt, and VEGF signaling pathways. Common interactors comprising E1A binding protein P300 (EP300), CREB binding protein (CBP), calcium/calmodulin dependent protein kinase II alpha (CaMKIIα) and sirtuin 1 (SIRT1) were found in both Reg-P14 and Reg-LI retinas. Proteins identified in both regenerating and degenerative groups were correlated to thyroid hormone, Notch, mRNA surveillance and measles signaling pathways, along with PD-L1 expression and the PD-1 checkpoint pathway. Common interactors across regenerative and degenerative retinas comprising NF-kappa-B p65 subunit (RELA), RNA-binding protein with serine-rich domain 1 (RNPS1), EP300 and SIN3 transcription regulator family member A (SIN3A). The findings from our study provide the first mapping of regenerative mechanisms across postnatal, mature and degenerative mouse retinas, revealing potential biomarkers that could facilitate neuro-regeneration in glaucoma.

Enhancing the Regeneration Performance of Methylene Blue Saturated Biochar in H2O2 System via Fe‐Doping

AbstractTo improve the regeneration efficiency of methylene blue (MB) saturated biochar in H2O2 system, biochar was modified by Fe‐doped by using FeSO4 and Fe(NO3)3 as iron sources. The effects of Fe‐doped on its microstructure were characterized by XRD, SEM, and BET. The adsorption and regeneration performance of biochar before and after Fe‐doped were compared through adsorption and regeneration experiments. X‐ray photoelectron spectroscopy, electron spin resonance, and quenching experiments were used to explore the regeneration mechanism. The results show that Fe‐doped biochar (SP‐GBC) prepared from FeSO4 maintains a high specific surface area of 1205.9 m2/g and a high adsorption capacity of 375.43 mg·g−1 for MB. After adsorption, the MB‐saturated SP‐GBC exhibits excellent regeneration performance in the H2O2 system, in which the regeneration efficiencies for five consecutive cycles are 85.76%, 83.92%, 94.01%, 99.24%, and 100.79%, respectively. The synergistic effect of H2O2 desorption and degradation is the main regeneration mechanism for MB‐saturated SP‐GBC. The zero valent iron and Fe (II) on the surface of SP‐GBC are the main active sites for H2O2 activation, while 1O2 and HO· are the main oxidation species. In summary, this work provides a simple and feasible method for the design and synthesis of adsorbents with highly efficient regeneration performance.

Pulmonary epithelial wound healing and the immune system. Mathematical modelling and bifurcation analysis of a bistable system

Respiratory diseases such as asthma, acute respiratory distress syndrome (ARDS), influenza or COVID-19 often directly target the epithelium. Elevated immune levels and a ‘cytokine storm’ are directly associated with defective healing dynamics of lung diseases such as COVID-19 or ARDS. The infected cells leave wounded regions in the epithelium which must be healed for the lung to return to a healthy state and carry out its main function of gas-exchange. Due to the complexity of the various interactions between cells of the lung epithelium and surrounding tissue, it is necessary to develop models that can complement experiments to fully understand the healing dynamics. In this mathematical study we model the mechanism of epithelial regeneration. We assume that healing is exclusively driven by progenitor cell proliferation, induced by a chemical activator such as epithelial growth factor (EGF) and cytokines such as interleukin-22 (IL22). Contrary to previous studies of wound healing, we consider the immune system, specifically the T effector cells TH1, TH17, TH22 and Treg to strongly contribute to the healing process, by producing IL22 or regulating the immune response. We therefore obtain a coupled system of two ordinary differential equations for the epithelial and immune cell densities and two functions for the levels of chemicals that either induce epithelial proliferation or recruit immune cells. These functions link the two cell equations. We find that to allow the epithelium to regenerate to a healthy state, the immune system must not exceed a threshold value at the onset of the healing phase. This immune threshold is supported experimentally but was not explicitly built into our equations. Our assumptions are therefore sufficient to reproduce experimental results concerning the ratio TH17/Treg cells as a threshold to predict higher mortality rates in patients. This immune threshold can be controlled by parameters of the model, specifically the base-level growth factor concentration. This conclusion is based on a mathematical bifurcation analysis and linearization of the model equations. Our results suggest treatment of severe cases of lung injury by reducing or suppressing the immune response, in an individual patient, assessed by their disease parameters such as course of lung injury and immune response levels.