Impact of Collared Peccaries Dycotiles tajacu (Artiodactyla: Tayassuidae) on understory vegetation in the tropical rainforest of the Nogal-La Selva Biological Corridor, Costa Rica / Impacto del pecarí de collar, Dycotiles tajacu (Artiodactyla: Tayassuidae) en la vegetación del sotobosque del bosque tropical húmedo del Corredor Biológico Local Nogal-La Selva, Costa Rica

Abstract Introduction: Evidence suggests that herbivores, such as peccaries, shape vegetation structure and diversity through predation, trampling, dispersal, and rooting behavior. Objective: To evaluate the impact of peccaries (Dycotiles tajacu) on the understory vegetation of the tropical rainforest in the Nogal-La Selva Local Biological Corridor, Costa Rica, comparing a site with the absence of peccaries to another with the presence of these animals. Methodology: From June to November 2021, 20 experimental exclusions and 20 free access plots, each measuring 2 m2 were used to quantify herbivory, the number of leaf blades, damaged leaves, healthy leaves, sapling height, and fallen biomass at both sites. Results: A higher sapling density was found in the Nogal Reserve, but a lower sapling diversity, while in La Selva there was a higher sapling diversity, but a lower density of seedlings. Herbivory and sapling height in La Selva exceeded those in Nogal. The exclusion of peccaries reduced seedling damage but did not affect the dynamics of fallen biomass. Conclusion: For the design, implementation, and evaluation of the effectiveness of biological corridors, it is crucial to consider plant-animal interactions to enhance the flow of ecological processes through functional and structural connectivity, analyzed from interactions such as those presented in this paper.

Resumen Introducción: Existe evidencia que herbívoros, como los saínos, dan forma a la estructura y diversidad de la vegetación a través del comportamiento de depredación, pisoteo, dispersión y enraizamiento. Objetivo: Evaluar el impacto de los saínos (Dycotiles tajacu) en la vegetación del sotobosque del bosque tropical húmedo en el Corredor Biológico Local Nogal-La Selva, Costa Rica, en un sitio con ausencia y en otro con presencia de saínos. Métodos: De junio a noviembre de 2021 se utilizaron 20 exclusiones experimentales y 20 parcelas de acceso libre de 2 m2, se cuantifico la herbivoría, número de láminas foliares, hojas dañadas, hojas sanas, altura de brinzales y biomasa caída en ambos sitios. Resultados: Se encontró una mayor densidad de brinzales en Reserva Nogal pero una menor diversidad, contrario en La Selva donde se encontró una mayor diversidad de brinzales, pero una menor densidad de plántulas. La herbivoría y la altura de brinzales en La Selva fue mayor que en Nogal. La exclusión de los saínos disminuyó el daño a las plántulas, pero no afectó la dinámica de la biomasa caída. Conclusión: Es necesario contemplar para el diseño, implementación y evaluación de la efectividad de corredores biológicos, las interacciones planta-animal, para potencializar el flujo de procesos ecológicos mediante la conectividad funcional y estructural, analizada a partir de interacciones como las presentadas en este trabajo.

Exploring the Efficacy of Biologics in Knee Osteoarthritis: Ultrasound Evaluation of Cartilage Regeneration Effects.

Introduction: Biologics like growth factors, stem cells, and platelet-rich plasma show potential in stimulating cartilage regrowth and reducing inflammation. By synthesizing preclinical and clinical studies, this study offers insights into how these biologics work and their effectiveness in treating knee osteoarthritis. Methods and Materials: Twenty-four participants with knee osteoarthritis (Kellgren - Lawrence grade II or III) were enrolled after obtaining consent. They received three doses of 2 ml intraarticular platelet-rich plasma at 1 month intervals. The clinical assessment involved the oxford knee score (OKS) and visual analogue scale (VAS) for pain on Days 0, 90, and 180. Ultrasound measured femoral and trochlear cartilage thickness pre- (Day 0) and post-PRP (Day 90-180). Results: Before treatment, the average pain score was 7.2 (p = 1.03). On Day 90 post-PRP, it decreased to 5 (p = 0.81), and by Day 180, it further reduced to 4.5 (p = 0.97). The initial total OKS was 33.5 (p = 1.76), which increased to 36 (p = 1.71) on Day 90 and 38.5 (p = 1.89) on Day 180. The femoral and trochlear cartilage thickness also showed improvement from baseline (0.92) to Day 90 (0.96) and Day 180 (1.01), indicating significant cartilage healing post-PRP administration. Conclusion: Our study highlights the probability of PRP in treating knee OA, highlighting their ability to alleviate symptoms, enhance joint function, and promote articular cartilage regeneration.

IL-4-induced SOX9 confers lineage plasticity to aged adult lung stem cells.

Wound healing in response to acute injury is mediated by the coordinated and transient activation of parenchymal, stromal, and immune cells that resolves to homeostasis. Environmental, genetic, and epigenetic factors associated with inflammation and aging can lead to persistent activation of the microenvironment and fibrosis. Here, we identify opposing roles of interleukin-4 (IL-4) cytokine signaling in interstitial macrophages and type II alveolar epithelial cells (ATIIs). We show that IL4Ra signaling in macrophages promotes regeneration of the alveolar epithelium after bleomycin-induced lung injury. Using organoids and mouse models, we show that IL-4 directly acts on a subset of ATIIs to induce the expression of the transcription factor SOX9 and reprograms them toward a progenitor-like state with both airway and alveolar lineage potential. In the contexts of aging and bleomycin-induced lung injury, this leads to aberrant epithelial cell differentiation and bronchiolization, consistent with cellular and histological changes observed in interstitial lung disease.

Baf155 controls hematopoietic differentiation and regeneration through chromatin priming.

Chromatin priming promotes cell-type-specific gene expression, lineage differentiation, and development. The mechanism of chromatin priming has not been fully understood. Here, we report that mouse hematopoietic stem and progenitor cells (HSPCs) lacking the Baf155 subunit of the BAF (BRG1/BRM-associated factor) chromatin remodeling complex produce a significantly reduced number of mature blood cells, leading to a failure of hematopoietic regeneration upon transplantation and 5-fluorouracil (5-FU) injury. Baf155-deficient HSPCs generate particularly fewer neutrophils, B cells, and CD8+ T cells at homeostasis, supporting a more immune-suppressive tumor microenvironment and enhanced tumor growth. Single-nucleus multiomics analysis reveals that Baf155-deficient HSPCs fail to establish accessible chromatin in selected regions that are enriched for putative enhancers and binding motifs of hematopoietic lineage transcription factors. Our study provides a fundamental mechanistic understanding of the role of Baf155 in hematopoietic lineage chromatin priming and the functional consequences of Baf155 deficiency in regeneration and tumor immunity.

Enhancing miR-19a/b induced cardiomyocyte proliferation in infarcted hearts by alleviating oxidant stress and controlling miR-19 release.

Fully restoring the lost population of cardiomyocytes and heart function remains the greatest challenge in cardiac repair post myocardial infarction. In this study, a pioneered highly ROS-eliminating hydrogel was designed to enhance miR-19a/b induced cardiomyocyte proliferation by lowering the oxidative stress and continuously releasing miR-19a/b in infarcted myocardium in situ. In vivo lineage tracing revealed that ∼20.47 % of adult cardiomyocytes at the injected sites underwent cell division in MI mice. In MI pig the infarcted size was significantly reduced from 40 % to 18 %, and thereby marked improvement of cardiac function and increased muscle mass. Most importantly, our treatment solved the challenge of animal death--all the treated pigs managed to live until their hearts were harvested at day 50. Therefore, our strategy provides clinical conversion advantages and safety for healing damaged hearts and restoring heart function post MI, which will be a powerful tool to battle cardiovascular diseases in patients.

Bioactive Polymer Composite Scaffolds Fabricated from 3D Printed Negative Molds Enable Bone Formation and Vascularization.

Scaffolds for bone defect treatment should ideally support vascularization and promote bone formation, to facilitate the translation into biomedical device applications. This study presents a novel approach utilizing 3D-printed water-dissolvable polyvinyl alcohol (PVA) sacrificial molds to engineer polymerized High Internal Phase Emulsion (polyHIPE) scaffolds with microchannels and distinct multiscale porosity. Two sacrificial mold variants (250 µm and 500 µm) were generated using fused deposition modeling, filled with HIPE, and subsequently dissolved to create polyHIPE scaffolds containing microchannels. In vitro assessments demonstrated significant enhancement in cell infiltration, proliferation, and osteogenic differentiation, underscoring the favorable impact of microchannels on cell behavior. High loading efficiency and controlled release of the osteogenic factor BMP-2 were achieved, with microchannels facilitating release of the growth factor. Evaluation in a mouse critical-size calvarial defect model revealed enhanced vascularization and bone formation in microchanneled scaffolds containing BMP-2. This study not only introduces an accessible method for creating multiscale porosity in polyHIPE scaffolds but also emphasizes its capability to enhance cellular infiltration, controlled growth factor release, and in vivo performance. The findings suggest promising applications in bone tissue engineering and regenerative medicine, and are expected to facilitate the translation of this type of biomaterial scaffold. STATEMENT OF SIGNIFICANCE: This study holds significance in the realm of biomaterial scaffold design for bone tissue engineering and regeneration. We demonstrate a novel method to introduce controlled multiscale porosity and microchannels into polyHIPE scaffolds, by utilizing 3D-printed water-dissolvable PVA molds. The strategy offers new possibilities for improving cellular infiltration, achieving controlled release of growth factors, and enhancing vascularization and bone formation outcomes. This microchannel approach not only marks a substantial stride in scaffold design but also demonstrates its tangible impact on enhancing osteogenic cell differentiation and fostering robust bone formation in vivo. The findings emphasize the potential of this methodology for bone regeneration applications, showcasing an interesting advancement in the quest for effective and innovative biomaterial scaffolds to regenerate bone defects.

Morphometric analysis and functional insights into the serotonergic system of Girardia tigrina (Tricladida, Platyhelminthes).

Using immunocytochemistry, serotonergic nerve elements were documented in the nervous system of the planarian Girardia tigrina. Serotonin-immunopositive components were observed in the brain, ventral, dorsal and longitudinal nerve cords, transverse nerve commissures connecting the nerve cords, and in the nerve plexus. Whole-mount preparations of G. tigrina were analyzed by fluorescent and confocal laser scanning microscopy. An essential quantitative morphometric measurement of serotonin-immunopositive structures was conducted in three body regions (anterior, middle, and posterior) of the planarian. The number of serotonin neurons was maximal in the head region. The ventral nerve cords gradually decreased in thickness from anterior to posterior body ends. Physiological action of exogenously applied serotonin was studied in G. tigrina for the first time. It was found that serotonin (0.1 and 1 µmol L-1) accelerated eye regeneration. The transcriptome sequencing performed for the first time for the planarian G. tigrina revealed the transcripts of the tryptophan hydroxylase (trph), amino acid decarboxylase (aadc) and serotonin transporter (sert) genes. The data obtained indicate the presence of the components of serotonin pathway in G. tigrina. The identified transcripts can take part in serotonin turnover and participate in the realization of biological effects of serotonin in planarians, associated with eyes regeneration and differentiation.

Resolvin D2-induced reparative dentin and pulp stem cells after pulpotomy in a rat model.

Introduction: Vital pulp therapy (VPT) is performed to preserve dental pulp. However, the biocompatibility of the existing materials is of concern. Therefore, novel materials that can induce pulp healing without adverse effects need to be developed. Resolvin D2 (RvD2), one of specialized pro-resolving mediators, can resolve inflammation and promote the healing of periapical lesions. Therefore, RvD2 may be suitable for use in VPT. In the present study, we evaluated the efficacy of RvD2 against VPT using in vivo and in vitro models. Methods: First molars of eight-week-old male Sprague-Dawley rats were used for pulpotomy. They were then divided into three treatment groups: RvD2, phosphate-buffered saline, and calcium hydroxide groups. Treatment results were assessed using radiological, histological, and immunohistochemical (GPR18, TNF-α, Ki67, VEGF, TGF-ß, CD44, CD90, and TRPA1) analyses. Dental pulp-derived cells were treated with RvD2 in vitro and analyzed using cell-proliferation and cell-migration assays, real-time PCR (Gpr18, Tnf-α, Il-1ß, Tgf-ß, Vegf, Nanog, and Trpa1), ELISA (VEGF and TGF-ß), immunocytochemistry (TRPA1), and flow cytometry (dental pulp stem cells: DPSCs). Results: The formation of calcified tissue in the pulp was observed in the RvD2 and calcium hydroxide groups. RvD2 inhibited inflammation in dental pulp cells. RvD2 promoted cell proliferation and migration and the expression of TGF-ß and VEGF in vitro and in vivo. RvD2 increased the number of DPSCs. In addition, RvD2 suppressed TRPA1 expression as a pain receptor. Conclusion: RvD2 induced the formation of reparative dentin, anti-inflammatory effects, and decreased pain, along with the proliferation of DPSCs via the expression of VEGF and TGF-ß, on the pulp surface in pulpotomy models.

In silico modeling the potential clinical effect of growth factor treatment on the metabolism of human nucleus pulposus cells.

Background: While growth factors have the potential to halt degeneration and decrease inflammation in animal models, the literature investigating the effect of dosage on human cells is lacking. Moreover, despite the completion of clinical trials using growth differentiation factor-5 (GDF-5), no results have been publicly released. Aims: The overall objective was to quantitatively assess the effect of three clinically relevant concentrations of GDF-5 (0.25, 1, and 2 mg) as a therapeutic for disc regeneration. Materials and methods: Firstly, this work experimentally determined the effects of GDF-5 concentration on the metabolic and matrix synthesis rates of human nucleus pulposus (NP) cells. Secondly, in silico modeling was employed to predict the subsequent regenerative effect of different GDF-5 treatments (± cells). Results: This study suggests a trend of increased matrix synthesis with 0.25 and 1 mg of GDF-5. However, 2 mg of GDF-5 significantly upregulates oxygen consumption. Despite this, in silico models highlight the potential of growth factors in promoting matrix synthesis compared to cell-only treatments, without significantly perturbing the nutrient microenvironment. Discussion: This work elucidates the potential of GDF-5 on human NP cells. Although the results did not reveal statistical differences across all doses, the variability and response among donors is an interesting finding. It highlights the complexity of human response to biological treatments and reinforces the need for further human research and personalized approaches. Furthermore, this study raises a crucial question about whether these potential biologics are more regenerative in nature or better suited as prophylactic therapies for younger patient groups. Conclusion: Biological agents exhibit unique characteristics and features, demanding tailored development strategies and individualized assessments rather than a one-size-fits-all approach. Therefore, the journey to realizing the full potential of biological therapies is long and costly. Nonetheless, it holds the promise of revolutionizing spinal healthcare and improving the quality of life for patients suffering from discogenic back pain.

Enhancing clinical safety in bioengineered-root regeneration: The use of animal component-free medium.

Background: Most studies used animal serum-containing medium for bioengineered-root regeneration, but ethical and safety issues raised by animal serum are a potentially significant risk for clinical use. Thus, this study aimed to find a safer method for bioengineered-root regeneration. Methods: The biological properties of human dental pulp stem cells (hDPSCs) cultured in animal component-free (ACF) medium or serum-containing medium (5%, 10% serum-containing medium, SCM) were compared in vitro. hDPSCs were cultured in a three-dimensional (3D) environment with human-treated dentin matrix (hTDM). The capacity for odontogenesis was compared using quantitative real-time PCR (qPCR) and Western blot. Subsequently, the hDPSCs/hTDM complexes were transplanted into nude mice subcutaneously. Histological staining was then used to verify the regeneration effect in vivo. Results: ACF medium promoted the migration of hDPSCs, but slightly inhibited the proliferation of hDPSCs in the first three days of culture compared to SCM. However, it had no significant effect on cell aging and apoptosis. After 7 days of 3D culture in ACF medium with hTDM, qPCR showed that DMP1, DSPP, OCN, RUNX2, and ß-tubulin III were highly expressed in hDPSCs. In addition, 3D cultured hDPSCs/hTDM complexes in ACF medium regenerated dentin, pulp, and periodontal ligament-like tissues similar to SCM groups in vivo. Conclusion: ACF medium was proved to be an alternative medium for bioengineered-root regeneration. The strategy of using ACF medium to regenerate bioengineered-root can improve clinical safety for tooth tissue engineering.

Weighted Gene Co-expression Network Analysis (WGCNA) of Wnt Signaling Related to Periodontal Ligament Formation: A Bioinformatics-Based Analysis.

Introduction The Wnt signaling pathway is crucial for tooth development, odontoblast differentiation, and dentin formation. It interacts with epithelial cadherin (E-cadherin) and beta-catenin in tooth development and periodontal ligament (PDL) formation. Dysregulation of Wnt signaling is linked to periodontal diseases, requiring an understanding of therapeutic interventions. Weighted gene co-expression network analysis (WGCNA) can identify co-expressed gene modules. Our study aims to identify hub genes in WGCNA analysis of Wnt signaling-based PDL formation. Methods The study used a microarray dataset GSE201313 from the National Center for Biotechnology Information (NCBI) Gene Expression Omnibus to analyze the impact of DMP1 expression on XLH dental pulp cell differentiation and PDL formation. The standardized dataset was used for WGCNA analysis, which generated a co-expression network by calculating pairwise correlations between genes and constructing an adjacency matrix. The topological overlap matrix (TOM) was transformed into a hierarchical clustering tree and then cut into modules or clusters of highly interconnected genes. The module eigengene (ME) was calculated for each module, and the genes within this module were identified as hub genes. Gene ontology (GO) and KEGG pathway enrichment analysis were performed to gain insights into the biological functions of the hub genes. The integrated Differential Expression and Pathway analysis (iDEP) tool (http://bioinformatics.sdstate.edu/idep/; South Dakota State University, Brookings, USA) was used for WGCNA analysis. Results The study used the WGCNA package to analyze 1,000 differentially expressed genes, constructing a gene co-expression network and generating a hierarchical clustering tree and TOM. The analysis reveals a scale-free topology fitting index R2 and mean connectivity for various soft threshold powers, with an R2 value of 5. COL6A1, MMP3, BGN, COL1A2, and FBN2 are hub genes implicated in PDL development. Conclusion The study identified key hub genes, including COL6A1, MMP3, BGN, and FBN2, crucial for PDL formation, tissue remodeling, and cell-matrix interactions, guiding future therapeutic strategies.

TMEM16A regulates satellite cell mediated skeletal muscle regeneration by ensuring a moderate level of caspase 3 activity.

It has been documented that caspase 3 activity is necessary for skeletal muscle regeneration, but how its activity is regulated is largely unknown. Our previous report shows that intracellular TMEM16A, a calcium activated chloride channel, significantly regulates caspase 3 activity in myoblasts during skeletal muscle development. By using a mouse line with satellite cell (SC)-specific deletion of TMEM16A, we examined the role of TMEM16A in regulating caspase 3 activity in SC (or SC-derived myoblast) as well as skeletal muscle regeneration. The mutant animals displayed apparently impaired regeneration capacity in adult muscle along with enhanced ER stress and elevated caspase 3 activity in Tmem16a-/- SC derived myoblasts. Blockade of either excessive ER stress or caspase 3 activity by small molecules significantly restored the inhibited myogenic differentiation of Tmem16a-/- SCs, indicating that excessive caspase 3 activity resulted from TMEM16A deletion contributes to the impaired muscle regeneration and the upstream regulator of caspase 3 was ER stress. Our results revealed an essential role of TMEM16A in satellite cell mediated skeletal muscle regeneration by ensuring a moderate level of caspase 3 activity.

Highly regenerative species-specific genes improve age-associated features in the adult Drosophila midgut.

BACKGROUND: The remarkable regenerative abilities observed in planarians and cnidarians are closely linked to the active proliferation of adult stem cells and the precise differentiation of their progeny, both of which typically deteriorate during aging in low regenerative animals. While regeneration-specific genes conserved in highly regenerative organisms may confer regenerative abilities and long-term maintenance of tissue homeostasis, it remains unclear whether introducing these regenerative genes into low regenerative animals can improve their regeneration and aging processes. RESULTS: Here, we ectopically express highly regenerative species-specific JmjC domain-encoding genes (HRJDs) in Drosophila, a widely used low regenerative model organism. Surprisingly, HRJD expression impedes tissue regeneration in the developing wing disc but extends organismal lifespan when expressed in the intestinal stem cell lineages of the adult midgut under non-regenerative conditions. Notably, HRJDs enhance the proliferative activity of intestinal stem cells while maintaining their differentiation fidelity, ameliorating age-related decline in gut barrier functions. CONCLUSIONS: These findings together suggest that the introduction of highly regenerative species-specific genes can improve stem cell functions and promote a healthy lifespan when expressed in aging animals.

The effect of salidroside in promoting endogenous neural regeneration after cerebral ischemia/reperfusion involves notch signaling pathway and neurotrophic factors.

BACKGROUND: Salidroside is the major bioactive and pharmacological active substance in Rhodiola rosea L. It has been reported to have neuroprotective effects on cerebral ischemia/reperfusion (I/R). However, whether salidroside can enhance neural regeneration after cerebral I/R is still unknown. This study investigated the effects of salidroside on the endogenous neural regeneration after cerebral I/R and the related mechanism. METHODS: Focal cerebral I/R was induced in rats by transient middle cerebral artery occlusion/reperfusion (MCAO/R). The rats were intraperitoneally treated salidroside once daily for 7 consecutive days. Neurobehavioral assessments were performed at 3 days and 7 days after the injury. TTC staining was performed to assess cerebral infarct volume. To evaluate the survival of neurons, immunohistochemical staining of Neuronal Nuclei (NeuN) in the ischemic hemisphere were conducted. Also, immunofluorescence double or triple staining of the biomarkers of proliferating neural progenitor cells in Subventricular Zone (SVZ) and striatum of the ischemia hemisphere were performed to investigate the neurogenesis. Furthermore, reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) were used to detect the expression of neurotrophic factors (NTFs) brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). Expression of Notch1 and its target molecular Hes1 were also analyzed by western-blotting and RT-PCR. RESULTS: Salidroside treatment ameliorated I/R induced neurobehavioral impairment, and reduced infarct volume. Salidroside also restored NeuN positive cells loss after I/R injury. Cerebral I/R injury significantly increased the expression of 5-Bromo-2'-Deoxyuridine (BrdU) and doublecotin (DCX), elevated the number of BrdU/Nestin/DCX triple-labeled cells in SVZ, and BrdU/Nestin/glial fibrillary acidic protein (GFAP) triple-labeled cells in striatum. Salidroside treatment further promoted the proliferation of BrdU/DCX labeled neuroblasts and BrdU/Nestin/GFAP labeled reactive astrocytes. Furthermore, salidroside elevated the mRNA expression and protein concentration of BDNF and NGF in ischemia periphery area, as well. Mechanistically, salidroside elevated Notch1/Hes1 mRNA expression in SVZ. The protein levels of them were also increased after salidroside administration. CONCLUSIONS: Salidroside enhances the endogenous neural regeneration after cerebral I/R. The mechanism of the effect may involve the regulation of BDNF/NGF and Notch signaling pathway.

Infection-Sensitive SPION/PLGA Scaffolds Promote Periodontal Regeneration via Antibacterial Activity and Macrophage-Phenotype Modulation.

Inflammation caused by a bacterial infection and the subsequent dysregulation of the host immune-inflammatory response are detrimental to periodontal regeneration. Herein, we present an infection-sensitive scaffold prepared by layer-by-layer assembly of Feraheme-like superparamagnetic iron oxide nanoparticles (SPIONs) on the surface of a three-dimensional-printed polylactic-co-glycolic acid (PLGA) scaffold. The SPION/PLGA scaffold is magnetic, hydrophilic, and bacterial-adhesion resistant. As indicated by gene expression profiling and confirmed by quantitative real-time reverse transcription polymerase chain reaction and flow cytometry analysis, the SPION/PLGA scaffold facilitates macrophage polarization toward the regenerative M2 phenotype by upregulating IL-10, which is the molecular target of repair promotion, and inhibits macrophage polarization toward the proinflammatory M1 phenotype by downregulating NLRP3, which is the molecular target of anti-inflammation. As a result, macrophages modulated by the SPS promote osteogenic differentiation of bone marrow mesenchymal stromal cells (BMSCs) in vitro. In a rat periodontal defect model, the SPION/PLGA scaffold increased IL-10 secretion and decreased NLRP3 and IL-1ß secretion with Porphyromonas gingivalis infection, achieving superior periodontal regeneration than the PLGA scaffold alone. Therefore, this antibacterial SPION/PLGA scaffold has anti-inflammatory and bacterial antiadhesion properties to fight infection and promote periodontal regeneration by immunomodulation. These findings provide an important strategy for developing engineered scaffolds to treat periodontal defects.

Polyphenol-Reinforced Glycocalyx-Like Hydrogel Coating Induced Myocardial Regeneration and Immunomodulation.

Although minimally invasive interventional occluders can effectively seal heart defect tissue, they still have some limitations, including poor endothelial healing, intense inflammatory response, and thrombosis formation. Herein, a polyphenol-reinforced medicine/peptide glycocalyx-like coating was prepared on cardiac occluders. A coating consisting of carboxylated chitosan, epigallocatechin-3-gallate (EGCG), tanshinone IIA sulfonic sodium (TSS), and hyaluronic acid grafted with 3-aminophenylboronic acid was prepared. Subsequently, the mercaptopropionic acid-GGGGG-Arg-Glu-Asp-Val peptide was grafted by the thiol-ene "click" reaction. The coating showed good hydrophilicity and free radical-scavenging ability and could release EGCG-TSS. The results of biological experiments suggested that the coating could reduce thrombosis by promoting endothelialization, and promote myocardial repair by regulating the inflammatory response. The functions of regulating cardiomyocyte apoptosis and metabolism were confirmed, and the inflammatory regulatory functions of the coating were mainly dependent on the NF-kappa B and TNF signaling pathway.

Degradation and regeneration inhibition of PCDD/Fs in incineration fly ash by low-temperature thermal technology.

Low-temperature thermal degradation of PCDD/Fs for incineration fly ash (IFA), as a novel and emerging technology approach, offers promising features of high degradation efficiency and low energy consumption, presenting enormous potential for application in IFA resource utilization processes. This review summarizes the concentrations, congener distributions, and heterogeneity characteristics of PCDD/Fs in IFA from municipal, medical, and hazardous waste incineration. A comparative analysis of five PCDD/Fs degradation technologies is conducted regarding their characteristics, industrial potential, and applicability. From the perspective of low-temperature degradation mechanisms, pathways to enhance PCDD/Fs degradation efficiency and inhibit their regeneration reactions are discussed in detail. Finally, the challenges to achieve low-temperature degradation of PCDD/Fs for IFA with high-efficiency are prospected. This review seeks to explore new opportunities for the detoxification and resource utilization of IFA by implementing more efficient and viable low-temperature degradation technologies.

Restoration of cone-circuit functionality in the regenerating adult zebrafish retina.

Unlike humans, teleosts like zebrafish exhibit robust retinal regeneration after injury from endogenous stem cells. However, it is unclear if regenerating cone photoreceptors regain physiological function and integrate correctly into post-synaptic circuits. We used two-photon calcium imaging of living adult retina to examine photoreceptor responses before and after light-induced lesions. To assess functional recovery of cones and downstream outer retinal circuits, we exploited color opponency; UV cones exhibit intrinsic Off-response to blue light, but On-response to green light, which depends on feedback signals from outer retinal circuits. Accordingly, we assessed the presence and quality of Off- vs. On-responses and found that regenerated UV cones regain both Off-responses to short-wavelength and On-responses to long-wavelength light within 3 months after lesion. Therefore, physiological circuit functionality is restored in regenerated cone photoreceptors, suggesting that inducing endogenous regeneration is a promising strategy for human retinal repair.

Synthesis and characterization of injectable thermosensitive hydrogel based on Pluronic-grafted silk fibroin copolymer containing hydroxyapatite nanoparticles as potential for bone tissue engineering.

Injectable hydrogels are promising for bone tissue engineering due to their minimally invasive application and adaptability to irregular defects. This study presents the development of pluronic grafted silk fibroin (PF-127-g-SF), a temperature-sensitive graft copolymer synthesized from SF and modified PF-127 via a carbodiimide coupling reaction. The PF-127-g-SF copolymer exhibited a higher sol-gel transition temperature (34 °C at 16 % w/v) compared to PF-127 (23 °C), making it suitable for injectable applications. It also showed improved flexibility and strength, with a yielding point increase from <10 % to nearly 30 %. Unlike PF-127 gel, which degrades within 72 h in aqueous media, the PF-127-g-SF copolymer maintained a stable gel structure for over two weeks due to its robust crosslinked hydrogel network. Incorporating hydroxyapatite nanoparticles (n-HA) into the hydrogel reduced pore size and decreased swelling and degradation rates, extending structural stability to four weeks. Increasing n-HA concentration from 0 % to 20 % reduced porosity from 80 % to 66 %. Rheological studies indicated that n-HA enhanced the scaffold's strength and mechanical properties without altering gelation temperature. Cellular studies with MG-63 cells showed that n-HA concentration influenced cell viability and mineralization, highlighting the scaffold's potential in bone tissue engineering.

A 3D-printed acinar-mimetic silk fibroin-collagen-astragalus polysaccharide scaffold for tissue reconstruction and functional repair of damaged parotid glands.

Salivary glands are the principal organs responsible for secreting saliva in the oral cavity. Tumors, trauma, inflammation, and other factors can cause functional or structural damage to the glands, leading to reduced saliva secretion. In this study, we innovatively prepared a acinar-mimetic silk fibroin-collagen-astragalus polysaccharide (SCA) scaffold using low-temperature three-dimensional (3D) printing and freeze-drying techniques. We evaluated the material properties and cell compatibility of the scaffold in vitro and implanted it into the damaged parotid glands (PG) of rats to assess its efficacy in tissue reconstruction and functional repair. The results demonstrated that the SCA scaffold featured a porous structure resembling natural acini, providing an environment conducive to cell growth and orderly aggregation. It exhibited excellent porosity, water absorption, mechanical properties, and biocompatibility, fulfilling the requirements for tissue engineering scaffolds. In vitro, the scaffold facilitated adhesion, proliferation, orderly polarization, and spherical aggregation of PG cells. In vivo, the SCA scaffold effectively recruited GECs locally, forming gland-like acinar structures that matured gradually, promoting the regeneration of damaged PGs. The SCA scaffold developed in this study supports tissue reconstruction and functional repair of damaged PGs, making it a promising implant material for salivary gland regeneration.