High Regenerative Capacity Research Articles

Peri-implant bone regeneration in pigs.

To review the current literature to answer the focused question: in the experimental pig model (population), which types of peri-implant bone defects (exposure) have been used evaluate different modes of therapy and what is their capacity for spontaneous healing and regeneration (outcome)? Following PRISMA guidelines, electronic databases were searched for studies reporting peri-implant bone defects in the maxillae or mandibles of pigs. Those studies which reported a control group of untreated defects with assessment of spontaneous regeneration [new bone area (BA)] and/or re-osseointegration [new bone-to-implant contact (BIC)] via quantitative radiography or histomorphometry were included in a random effects meta-analysis for the outcomes BA and BIC. Overall, 21 studies, mostly performed in the mandibles of minipigs, were included. Most studies reported 'acute' intrabony (circumferential and/or dehiscence; n = 12) or supra-alveolar defects (horizontal; n = 4). Five studies attempted to induce 'chronic' peri-implantitis lesions using ligatures with conflicting results. Meta-analyses revealed pooled estimates (with 95% confidence intervals) of 48.07% BIC (30.14-66%) and 64.31% BA (42.71-85.91%) in intrabony defects, and 52.09% BIC (41.83-62.35%) and 28.62% BA (12.97-44.28%) in supra-alveolar defects. Heterogeneity in the meta-analysis was high (I2 > 90%). Current evidence for peri-implant bone regeneration in pigs is mainly based on acute intrabony defects, which demonstrate a high capacity for spontaneous regeneration and re-osseointegration. The evidence for chronic peri-implantitis is limited and does not clearly indicate a spontaneous progression of the disease in this animal model.

Novel nerve regeneration assessment method using adult zebrafish with crush spinal cord injury.

Zebrafish (Danio rerio), an alternative to rodents, are widely used in neurological, genetic, and toxicology research. The zebrafish larval spinal cord injury model has been used in neural mechanistic analyses owing to its high regenerative capacity and throughput; however, it also had several limitations in imitating rodents. Therefore, we investigated the use of adult zebrafish as an alternative model to rodents for evaluating nerve regeneration. Here, we established a novel spinal cord regeneration evaluation method, which was based on the maximum swimming speed of adult zebrafish in a custom-built hydrodynamic-based aquarium. The spinal cords of adult male zebrafish were crushed using forceps, and maximum swimming speed and histological spinal cord regeneration were evaluated. Spinal cord-injured zebrafish showed a significant decline in motor function, followed by recovery at 3weeks postoperatively, accompanied by histological regeneration. Spinal cord regeneration can be indirectly assessed by monitoring maximum swimming speed. They were also fed a diet containing fig extract, which can promote peripheral nerve regeneration; they were fed daily starting 1week before the operation. Maximum swimming speed was measured time-dependently until 3weeks postoperatively. Fig-consuming fish showed improved recovery of maximum swimming speed compared to the controls, which was consistent with the histological analysis. In summary, we established a spinal cord regeneration assessment system using adult zebrafish in a customized aquarium, which enables researchers to evaluate spinal cord regeneration in adult zebrafish similar to that of rodent experiments, contributing to faster and easier screening of neuroregenerative technology.

Graphitic carbon nitride-modified cerium ferrite: an efficient photocatalyst for the degradation of ciprofloxacin, ampicillin, and erythromycin in aqueous solution

Incomplete removal of antibiotics by most known wastewater treatment plants is a global challenge. Therefore, graphitic carbon nitride-modified cerium ferrite (CeFe2O4@g-C3N4) was synthesized to remove antibiotics (ampicillin, ciprofloxacin and erythromycin) from water. CeFe2O4@g-C3N4 showed activity in the visible light with a Tauc plot revealing the bandgap energy (2.46 eV). The scanning electron micrograph (SEM) result revealed the surface of CeFe2O4@g-C3N4 to be heterogeneous, while the transmission electron micrograph (TEM) image confirmed a flaky with rod and oval shaped surface (average particle size of 42.22 nm). CeFe2O4@g-C3N4 exhibited a 100% removal of all the studied antibiotics from aqueous solution in a photocatalytic degradation that is described by pseudo-1st-order kinetics. CeFe2O4@g-C3N4 demonstrated a high regeneration capacity, which is above 90% at the 12th cycle of treatment without any observable changes in its phase structure which suggests a promising chemical stability and reusability. CeFe2O4@g-C3N4 compared favourably with some selected antibiotic degradable photocatalysts suggesting the economic viable of CeFe2O4@g-C3N4 as photocatalyst for the purification of antibiotics-contaminated water.Graphical

Selection and validation of reference genes for quantitative expression analysis of regeneration-related genes in Cheilomenes sexmaculata by real-time qRT-PCR.

Regeneration is a fascinating phenomenon that has intrigued scientists for a long time. Cheilomenes sexmaculata (Fabricius), a zig-zag ladybird beetle, possesses a high capacity for limb regeneration. The molecular mechanics of the zig-zag ladybird beetle are under-explored. Current research trends are focused on uncovering functional genes associated with limb regeneration. Most of these investigations involve quantitative real-time PCR (qRT-PCR) for their rapid and accurate analysis of gene expression levels. Hence, a stable and suitable reference gene is required to normalize the gene expression data. In this study, five housekeeping genes were selected from the transcriptomics data (in-house unpublished data) of C. sexmaculata (Fabricius). The expression stabilities of the selected genes were evaluated under different time intervals post-amputation using geNorm, normFinder, and refFinder software. Actin was revealed to be the most stable housekeeping gene, along with elongation factor 2 and glyceraldehyde-3-phosphate dehydrogenase. A target gene named engrailed (an important segment-forming gene) was used to validate the selected reference genes. The expression levels were found to be consistent with the transcriptomics results. According to our study, actin, along with elongation factor 2 and glyceraldehyde-3-phosphate dehydrogenase, serve as the most stable reference genes and are suitable for regeneration-related research. This study is a groundbreaking effort to identify the most stable reference gene for limb regeneration in C. sexmaculata (Fabricius), and the findings can be applied to other related insect species.

Regeneration of the caudal fin of the evolutionary ancient tropical gar Atractosteus tropicus

BackgroundThe tropical gar (Atractosteus tropicus), a member of the Lepisosteidae family, is native to regions extending from southeastern Mexico to southern Costa Rica. This species serves as a unique bridge between tetrapods and teleosts due to its phylogenetic position, slow evolutionary rate, dense genetic map, gene similarities with humans, and ease of laboratory cultivation. As a taxonomic sister group to teleosts like the zebrafish (Danio rerio), known for its high regenerative capacity, it remains unclear whether the tropical gar shares a similar ability for regeneration.ResultsThis study aims to elucidate the caudal fin regeneration process in tropical gar through skeletal and histological staining methods. Juvenile specimens were observed over a two-month period, during which they were fed brine shrimp, and anesthetized with 1% eugenol for caudal fin amputation. Samples were collected at various days post-amputation (dpa). Alcian blue and alizarin red staining were used to highlight skeletal regeneration, particularly the formation of new cartilage, while histological staining with hematoxylin and eosin was performed to observe tissue regeneration at the amputation site.ConclusionsThe findings reveal a remarkable ability for caudal fin regeneration in juvenile tropical gar. Given the Garfish evolutionary relationship with teleosts, this opens new avenues for research into tissue regeneration across different groups of Actinopterygii.

LRRK2 kinase activity is necessary for development and regeneration in Nematostella vectensis

BackgroundThe starlet sea anemone, Nematostella vectensis, is an emerging model organism with a high regenerative capacity, which was recently found to possess an orthologue to the human Leucine Rich Repeat Kinase 2 (LRRK2) gene. Mutations in this gene are the most common cause of inherited Parkinson’s Disease (PD), highlighting the importance of understanding its function. Despite two decades of research, however, the function of LRRK2 is not well established.MethodsTo investigate the function of LRRKs in Nematostella vectensis, we applied small molecule inhibitors targeting the kinase activity of LRRK2 to examine its function in development, homeostasis and regeneration in Nematostella vectensis.ResultsIn vivo analyses inhibiting the kinase function of this enzyme demonstrated a role of nvLRRK2 in development and regeneration of N. vectensis. These findings implicate a developmental role of LRRK2 in Nematostella, adding to the expanding knowledge of its physiological function.ConclusionsOur work introduces a new model organism with which to study LRRK biology. We report that LRRK kinase activity is necessary for the development and regeneration of Nematostella. Given the short generation time, genetic trackability and in vivo imaging capabilities, this work introduces Nematostella vectensis as a new model in which to study genes linked to neurodegenerative diseases such as Parkinson’s.

An Exosome-Laden Hydrogel Wound Dressing That Can Be Point-of-Need Manufactured in Austere and Operational Environments.

Skin wounds often form scar tissue during healing. Early intervention with tissue-engineered materials and cell therapies may promote scar-free healing. Exosomes and extracellular vesicles (EV) secreted by mesenchymal stromal cells (MSC) are believed to have high regenerative capacity. EV bioactivity is preserved after lyophilization and storage to enable use in remote and typically resource-constrained environments. We developed a bioprinted bandage containing reconstituted EVs that can be fabricated at the point-of-need. An alginate/carboxymethyl cellulose (CMC) biomaterial ink was prepared, and printability and mechanical properties were assessed with rheology and compression testing. Three-dimensional printed constructs were evaluated for Young's modulus relative to infill density and crosslinking to yield material with stiffness suitable for use as a wound dressing. We purified EVs from human MSC-conditioned media and characterized them with nanoparticle tracking analysis and mass spectroscopy, which gave a peak size of 118 nm and identification of known EV proteins. Fluorescently labeled EVs were mixed to form bio-ink and bioprinted to characterize EV release. EV bandages were bioprinted on both a commercial laboratory bioprinter and a custom ruggedized 3D printer with bioprinting capabilities, and lyophilized EVs, biomaterial ink, and thermoplastic filament were deployed to an austere Arctic environment and bioprinted. This work demonstrates that EVs can be bioprinted with an alginate/CMC hydrogel and released over time when in contact with a skin-like substitute. The technology is suitable for operational medical applications, notably in resource-limited locations, including large-scale natural disasters, humanitarian crises, and combat zones.

Antibody-mediated rejection in post-liver transplant clinical care: Are we there yet for timely diagnosis and treatment?

With improvements in medical management and surgical technique in the field of solid organ transplantation, many historically prominent causes of liver allograft injury have been ameliorated or, in the case of Hepatitis C virus, eliminated altogether. In this transformed clinical landscape, antibody-mediated rejection (AMR) has emerged as a defining barrier to maintenance of long-term liver allograft function. The liver's unique anatomy, high regenerative capacity, and tolerogenic immunological environment tend to mitigate the severest AMR manifestations. Consequently, the clinical importance of AMR in the liver has been recognized more slowly than for other solid organ allografts. Significant strides have been made in elucidating clinical and histopathologic features of acute and chronic liver AMR, with the Banff 2016 criteria among the most notable. However, current histopathologic definitions of AMR are lacking in sensitivity and specificity. C4d staining is an imperfect biological surrogate for antibody-mediated injury, and suffers from significant technical limitations. The frequent co-occurrence of T cell mediated rejection and non-immunologic allograft damage (including recurrence of primary disease) also hinders definitive identification of AMR and results in misattribution of its effects. The goal of this review is to summarize the current understanding of AMR in the context of liver transplantation, including risk factors, pathogenesis, and current diagnostic and treatment strategies. Potential directions of future research are also addressed.

Comparative transcriptomic profiling reveals a role for Olig1 in promoting axon regeneration

The regenerative potential of injured axons displays considerable heterogeneity. However, the molecular mechanisms underlying the heterogeneity have not been fully elucidated. Here, we establish a method that can separate spinal motor neurons (spMNs) with low and high regenerative capacities and identify a set of transcripts revealing differential expression between two groups of neurons. Interestingly, oligodendrocyte transcription factor 1 (Olig1), which regulates the differentiation of various neuronal progenitors, exhibits recurrent expression in spMNs with enhanced regenerative capabilities. Furthermore, overexpression of Olig1 (Olig1 OE) facilitates axonal regeneration in various models, and down-regulation or deletion of Olig1 exhibits an opposite effect. By analyzing the overlapped differentially expressed genes after expressing individual Olig factor and functional validation, we find that the role of Olig1 is at least partially through the neurite extension factor 1 (Nrsn1). We therefore identify Olig1 as an intrinsic factor that promotes regenerative capacity of injured axons.

A photocatalyst coupled amphiphobic membrane with enhanced antifouling and self-regenerating properties for oily aerosol filtration

Oily aerosols as the most adhesive particles in the air can cause irreversible fouling of filters. Amphiphobic surface of filters can to some extent reduce membrane fouling, but complex oil fouling will still adhere to the membrane surface, leading to a decrease in membrane separation performance over long-term use. Herein, a silicon carbide (SiC) membrane with amphiphobic properties and catalytic functions was developed to collaboratively combat pollution. Low surface free energy 1H,1H,2H,2H perfluorooctyltrichlorosilane (FOTS) monomer and TiO2 nanoparticles were individually applied to the SiC membrane. PDMS was utilized to protect the monomer from degradation by the catalyst. The membrane exhibits good anti-adhesion and photocatalysis performance for oily aerosols. The membrane exhibits excellent oily aerosol filtration efficiency (98.6 %) with a comparative low filtration resistance of 6.4 kPa, as well as a high capacity for regeneration. Under UV light, the membrane can degrade oily fouling to recover its amphiphobic property. After 5 cycles of filtration, it still maintains good repeatability for oily matter separation and degradation. This study offers a practical approach to designing a membrane that enables long-term and efficient cleaning of oily aerosols.

Single high-dose intravenous injection of Wharton’s jelly-derived mesenchymal stem cell exerts protective effects in a rat model of metabolic syndrome

BackgroundMetabolic syndrome (MetS) is a significant epidemiological problem worldwide. It is a pre-morbid, chronic and low-grade inflammatory disorder that precedes many chronic diseases. Wharton’s jelly-derived mesenchymal stem cells (WJ-MSCs) could be used to treat MetS because they express high regenerative capacity, strong immunomodulatory properties and allogeneic biocompatibility. This study aims to investigate WJ-MSCs as a therapy against MetS in a rat model.MethodsTwenty-four animals were fed with high-fat high-fructose (HFHF) diet ad libitum. After 16 weeks, the animals were randomised into treatment groups (n = 8/group) and received a single intravenous administration of vehicle, that is, 3 × 106 cells/kg or 10 × 106 cells/kg of WJ-MSCs. A healthy animal group (n = 6) fed with a normal diet received the same vehicle as the control (CTRL). All animals were periodically assessed (every 4 weeks) for physical measurements, serum biochemistry, glucose tolerance test, cardiovascular function test and whole-body composition. Post-euthanasia, organs were weighed and processed for histopathology. Serum was collected for C-reactive protein and inflammatory cytokine assay.ResultsThe results between HFHF-treated groups and healthy or HFHF-CTRL did not achieve statistical significance (α = 0.05). The effects of WJ-MSCs were masked by the manifestation of different disease subclusters and continuous supplementation of HFHF diet. Based on secondary analysis, WJ-MSCs had major implications in improving cardiopulmonary morbidities. The lungs, liver and heart show significantly better histopathology in the WJ-MSC-treated groups than in the untreated CTRL group. The cells produced a dose-dependent effect (high dose lasted until week 8) in preventing further metabolic decay in MetS animals.ConclusionsThe establishment of safety and therapeutic proof-of-concept encourages further studies by improving the current therapeutic model.

Emilin2 marks the target region for mesenchymal cell accumulation in bone regeneration

BackgroundRegeneration of injured tissue is dependent on stem/progenitor cells, which can undergo proliferation and maturation processes to replace the lost cells and extracellular matrix (ECM). Bone has a higher regenerative capacity than other tissues, with abundant mesenchymal progenitor cells in the bone marrow, periosteum, and surrounding muscle. However, the treatment of bone fractures is not always successful; a marked number of clinical case reports have described nonunion or delayed healing for various reasons. Supplementation of exogenous stem cells by stem cell therapy is anticipated to improve treatment outcomes; however, there are several drawbacks including the need for special devices for the expansion of stem cells outside the body, low rate of cell viability in the body after transplantation, and oncological complications. The use of endogenous stem/progenitor cells, instead of exogenous cells, would be a possible solution, but it is unclear how these cells migrate towards the injury site.MethodsThe chemoattractant capacity of the elastin microfibril interface located protein 2 (Emilin2), generated by macrophages, was identified by the migration assay and LC–MS/MS. The functions of Emilin2 in bone regeneration were further studied using Emilin2–/– mice.ResultsThe results show that in response to bone injury, there was an increase in Emilin2, an ECM protein. Produced by macrophages, Emilin2 exhibited chemoattractant properties towards mesenchymal cells. Emilin2–/– mice underwent delayed bone regeneration, with a decrease in mesenchymal cells after injury. Local administration of recombinant Emilin2 protein enhanced bone regeneration.ConclusionEmilin2 plays a crucial role in bone regeneration by increasing mesenchymal cells. Therefore, Emilin2 can be used for the treatment of bone fracture by recruiting endogenous progenitor cells.

#2145 Sexual dimorphism in kidney regenerative capacity decline and in progressive tubular cell polyploidization during aging

Abstract Background and Aims Aging is characterized by a progressive kidney function decline, resulting in chronic kidney disease (CKD), which is steeper in men than in women. However, sex-related differences in mechanisms underpinning CKD development during aging still remain to be clarified. In most organs regenerative capacity declines overtime from a pool of resident stem cells leading to tissue aging. In the kidney, we have revealed that two adaptive responses co-exist to recover kidney function after injury. On one hand a population of renal progenitors (RPC), which is interspersed among parietal epithelial cells of Bowman's capsule and tubular cells (TC) of nephron segments, proliferate and generate new podocytes and TC to recover structural integrity during the regenerative processes occurring in glomerular and tubular diseases. On the other, TC enter the alternative cell cycles to become polyploid in order to increase their functional capacity and maintain the residual kidney function after injury. However, a continuous TC polyploidization comes with the long term trade-offs (fibrosis and senescence), driving CKD. Here, we aimed to investigate the role of sexual dimorphism in these two different adaptive responses during aging. Method To trace RPC (Pax2+cells) we used the inducible Pax2/Confetti or Pax2/mTmG mice (RPC are randomly labelled by one of the four fluorescent reporter genes or with GFP respectively). To study polyploid TC, we used the inducible Pax8/FUCCI2aR mice (polyploid TC are identified by expression of cell cycle fluorescent proteins in combination with DNA content analysis). Mice were analyzed at 2, 5, 12 and 20 months of age. scRNA sequencing was performed at 2 and 20 months of age. Results Pax2/Confetti mice revealed that the number of Pax2+RPC either of the Bowman's capsule or in tubules was higher in female than in male mice at all ages. Specifically, tracing analysis during aging showed that in females Pax2+RPC of the Bowman's capsule generated new podocytes, resulting in glomeruli with a better integrity of the slit-diaphragm compared with aged males. Moreover, tubular Pax2+RPC in females clonally expanded, generating a higher number of clones, which were longer than those in males. scRNAseq analysis on kidneys showed that females were endowed with a greater number of Pax2+RPC with a higher expression of Pax2 than males, suggesting that RPC in females kept a higher regenerative capacity than males during aging. Simultaneously, analysis of tubular polyploidy demonstrated that, whereas in females the polyploid fraction progressively increased, it was drastically reduced in males during aging. These results suggested that whereas in females the increase of polyploid TC provided a better maintenance of kidney function overtime, loss of polyploid response in males made them more susceptible to develop CKD. Indeed, aged male mice showed a higher percentage of polyploid TC undergoing further cycles of polyploidization, which were associated with fibrosis and senescence. In agreement with these findings, we observed a progressive kidney function decline along with an increase of glomerulosclerosis, interstitial fibrosis and blood pressure, which were significantly greater in males than in females. Conclusion Female mice showed a higher regenerative and polyploid response compared to male mice, aimed likely to cope kidney function decline during aging. These results reveal the intriguing role of a new kidney adaptive response, which may explain the higher susceptibility of males to develop a more premature CKD during aging.

Amyloid fibril–bacterial cellulose nanohybrid membrane cartridge for efficient removal of heavy metal from industrial wastewater

ABSTRACT Worldwide, the harmful ion contamination of water has become a serious problem because of unregulated industry, energy production, and mining, which greatly increase the concentration of pollutants in water. The novel membranes through adsorbent self-assembly, such as protein amyloids, were explored for wastewater treatment. Herein, we report amyloid fibril (AF)-embedded bacterial cellulose nanohybrid membrane for efficient removal of heavy metal from industrial effluent. AFs are synthesized by heat treatment using bovine serum albumin and embedded with bacterial cellulose nanomembrane (BCN). The AF-embedded BCN (AF/BCN) was characterized using microscopy and spectroscopic methods. In addition, the well-ordered multi-layered AF/BCN filtration assembly was fabricated in the commercial cartridge and validated for the removal of heavy metals (Pb2+ and Hg2+) from wastewater and treatment of industrial wastewater sample containing heavy metals. Our multi-layered filtration assembly removed Hg2+ and Pb2+ with efficiency of 95 and 78.34%, respectively. A computational study using molecular docking has also been performed for the identification of metal entrapment sites. Moreover, our AF/BCN filtration assembly showed high regeneration capacity up to four cycles. The isotherm model also revealed a strong fit and good adsorption behaviour. This makes potential filtration assembly for low-cost, high-efficiency for the removal of heavy metal from wastewater.

Recovery status of coastal vegetation in Mozambique: Insights from floristic composition and soil organic carbon analysis

The growing demand for land for slash-and-burn cultivation, driven by human population growth, has led to the creation of scattered cultivated fields and a mosaic of fallow areas in various stages of regeneration. While tropical forests have demonstrated the ability to rebound regarding tree species diversity and forest structure following disturbances, the extent of recovery in coastal vegetation in southern Africa remains uncertain and poorly understood. To address this knowledge gap, our study collected biophysical data from smallholder fields, fallow land, and forests to evaluate the structure and functioning of coastal vegetation in Gaza province, southern Mozambique. We established 90 sample plots of 0.1 ha each at different stages of plant succession using opportunistic sampling approach. Within these plots, we recorded the diameter at breast height, total height, and species name of all trees and shrubs. Litter and soil samples were collected in 1 m² quadrats embedded within the main plot. Our findings indicate a high capacity for regeneration following the disturbance caused by slash-and-burn cultivation. Species composition varied significantly across different stages of succession, with 52 species identified in forests (FL), 34 in old fallow (OF), 29 in middle fallow (MF), 28 in initial fallow (IF), and 15 in cropland (CL). Richness and diversity increased over time after the practice of slash-and-burn cultivation, with a noticeable enhancement from the initial fallow stage. We observed a gradual recovery of soil carbon stocks in young fallow areas, while litter biomass decreased throughout the recovery phase of the fallow lands. Our study highlights that areas abandoned after agriculture can regenerate in terms of structure, floristic composition, and tree carbon content.

Amelioration of NAFLD by sleeve gastrectomy-triggered hepatocyte regeneration in mice - experimental research.

Sleeve gastrectomy (SG) is known to alleviate non-alcoholic fatty liver disease (NAFLD) and restore liver function; however, its underlying mechanism remains unclear. We investigated the effect of SG on the metabolic phenotype of diet-induced obese (DIO) mice. Postoperative stained liver images were analyzed to determine the hepatocyte proliferation phenotype. Single-cell RNA sequencing was used to characterize the regeneration signals of the liver after SG in DIO mice, and qRT PCR was performed to verify the above results. We employed Olink proteomics to capture serum element changes and investigated the role of Yes1 protein in liver regeneration and carcinogenesis through the Hippo-YAP pathway. DIO mice were treatment with YAP inhibitor verteporfin after SG mice to clarify whether SG-induced liver regeneration is related to the YAP signaling pathway. SG significantly reduced NAFLD-associated dysfunction in hepatocytes and replaced them with fully functional hepatocytes, which have a high regenerative capacity across the entire liver. SG also enhanced the hepatic regenerative capacity, as demonstrated by SG combined with hepatic lobectomy in healthy mice. Yes1 protein was identified as the signaling molecule most closely related to classical regeneration signals. Our study showed that SG-enhanced proliferation and improved metabolism did not depend on YAP signaling. SG can enhance hepatic regenerative capacity and improve liver metabolism. This study provides a better understanding of the mechanisms underlying SG-induced metabolic improvements.

A group-targeting biosensor for sensitive and rapid detection of quinolones in water samples

BackgroundQuinolones (QNs) widely exist in the environment due to their wide range of applications and poor metabolic properties, resulting in the generation and spread of resistance genes, posing a potential threat to human health. Traditional analytical methods cannot detect all broad ranges of QNs simultaneously. The development of facile, efficient and reliable method for quantification and assessment of the total QNs is a long-lasting challenge. ResultsWe hereby provide a simple, sensitive and instantaneous group-targeting biosensor for the detection of total QNs in environmental water samples. The biosensor is based on a group-specific antibodies with high affinity against QNs. Fluorescent labeled antibodies bound to the coated antigen modified on the surface of the transducer, and excited by the evanescent waves. The detected fluorescent signal is inversely proportional to the QNs concentration. This biosensor exhibited excellent performance with detection limits lower than 0.15 μg L−1 for all five QNs variants, and even lower than 0.075 μg L−1 for ciprofloxacin (CIP) and ofloxacin (OFL). Environmental water samples can be detected after simple pretreatment, and all detection steps can be completed in 10 min. The transducer has a high regenerative capacity and shows no significant signal degradation after two hundred detection cycles. The recoveries of QNs in a variety of wastewater range from 105 to 119%, confirming its application potential in the measurement of total QNs in reality. SignificanceThe biosensor can realize rapid and sensitive detection of total QNs in water samples by simple pretreatment, which overcomes the disadvantage of the traditional methods that require complex pretreatment and time-consuming, and pave the groundwork for expansive development centered around this technology.

Regeneration of alveolar bone defects in the experimental pig model: A systematic review and meta-analysis.

Pigs are emerging as a preferred experimental invivo model for bone regeneration. The study objective was to answer the focused PEO question: in the pig model (P), what is the capacity of experimental alveolar bone defects (E) for spontaneous regeneration in terms of new bone formation (O)? Following PRISMA guidelines, electronic databases were searched for studies reporting experimental bone defects or extraction socket healing in the maxillae or mandibles of pigs. The main inclusion criteria were the presence of a control group of untreated defects/sockets and the assessment of regeneration via 3D tomography [radiographic defect fill (RDF)] or 2D histomorphometry [new bone formation (NBF)]. Random effects meta-analyses were performed for the outcomes RDF and NBF. Overall, 45 studies were included reporting on alveolar bone defects or extraction sockets, most frequently in the mandibles of minipigs. Based on morphology, defects were broadly classified as 'box-defects' (BD) or 'cylinder-defects' (CD) with a wide range of healing times (10 days to 52 weeks). Meta-analyses revealed pooled estimates (with 95% confidence intervals) of 50% RDF (36.87%-63.15%) and 43.74% NBF (30.47%-57%) in BD, and 44% RDF (16.48%-71.61%) and 39.67% NBF (31.53%-47.81%) in CD, which were similar to estimates of socket-healing [48.74% RDF (40.35%-57.13%) and 38.73% NBF (28.57%-48.89%)]. Heterogeneity in the meta-analysis was high (I2 > 90%). A substantial body of literature revealed a high capacity for spontaneous regeneration in experimental alveolar bone defects of (mini)pigs, which should be considered in future studies of bone regeneration in this animal model.

Gene-expression patterns during regeneration of the multi-organ complex after evisceration in the sea cucumber Eupentacta quinquesemita

Many species of sea cucumbers (Echinodermata, Holothuroidea) perform evisceration, i.e., ejection of internal organs including digestive tracts when responding to environmental stresses. After evisceration, they also show a high regenerative capacity, in which all the eviscerated organs regenerate. Especially in anterior evisceration species, the oral complex structure consisting of multiple organs, including the digestive tract and central nervous system, are reconstructed. The detailed developmental mechanisms underlying the process remains unclear, and therefore, in this study, focusing on Eupentacta quinquesemita, gene expression analyses in the regenerating tissues were carried out. For the formation of the gut tube, genes involved in mesenchymal-epithelial transition were upregulated consistently with the histological changes. Upregulation of Hox and Parahox genes along the anterior-posterior axis was observed, implying the involvement of these genes in the spatial differentiation of the digestive tract. In addition, the expression of otx, six and pax, i.e., transcription factors patterning anterior nervous tissues, was upregulated during the regeneration of the central nervous system. Taken together, these results suggest that conserved genes are co-opted to the internal organ regeneration after evisceration in sea cucumbers.

Adsorption of high-temperature CO2 by Ca2+/Na+-doped lithium orthosilicate: characterization, kinetics, and recycle.

High-temperature solid adsorbent Li4SiO4 has received broad attention due to its high theoretical adsorption capacity, high regeneration capacity, and wide range of raw materials for preparation. In this paper, a Li4SiO4 adsorbent was prepared by MCM-48 as the silica precursor and modified by doping with metal ions (Ca2+ and Na+) for high-temperature capture of low-concentration CO2. The results showed that the surface of the Ca-doped (or Na-doped) Li4SiO4 adsorbent developed some particles that are primarily composed by Li2CaSiO4 (or Li3NaSiO4). Furthermore, the grains of the adsorbents became finer, effectively increasing the specific surface area and enhancing adsorption performance. Under 15 vol% CO2, the maximum CO2 adsorption was 25.63 wt% and 32.86 wt% when the Ca2+ doping amount was 0.06 and the Na+ doping amount was 0.12, respectively. These values were both higher than the adsorption capacity before the metal ion doping. After 10 adsorption/desorption cycles, the adsorption capacity of Na-doped Li4SiO4 increased by 9.68 wt%, while that of Ca-doped Li4SiO4 decreased by 7.98 wt%. This difference could be attributed to the easy sintering of the Ca-containing adsorbent. Furthermore, a biexponential model was used to fit the CO2 adsorption curve of the adsorbent in order to study the adsorption kinetics. Compared to the conventional Li4SiO4, the Ca/Na-doped adsorbent offers several advantages, such as a high CO2 adsorption capacity and stable cycling ability.