Pro-angiogenic photo-crosslinked silk fibroin hydrogel: a potential candidate for repairing alveolar bone defects

Objective: This study aimed to develop a pro-angiogenic hydrogel with in situ gelation ability for alveolar bone defects repair. Methodology: Silk fibroin was chemically modified by Glycidyl Methacrylate (GMA), which was evaluated by proton nuclear magnetic resonance (1H-NMR). Then, the photo-crosslinking ability of the modified silk fibroin was assessed. Scratch and transwell-based migration assays were conducted to investigate the effect of the photo-crosslinked silk fibroin hydrogel on the migration of human umbilical vein endothelial cells (HUVECs). In vitro angiogenesis was conducted to examine whether the photo-crosslinked silk fibroin hydrogel would affect the tube formation ability of HUVECs. Finally, subcutaneous implantation experiments were conducted to further examine the pro-angiogenic ability of the photo-crosslinked silk fibroin hydrogel, in which the CD31 and α-smooth muscle actin (α-SMA) were stained to assess neovascularization. The tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were also stained to evaluate inflammatory responses after implantation. Results: GMA successfully modified the silk fibroin, which we verified by our 1H-NMR and in vitro photo-crosslinking experiment. Scratch and transwell-based migration assays proved that the photo-crosslinked silk fibroin hydrogel promoted HUVEC migration. The hydrogel also enhanced the tube formation of HUVECs in similar rates to Matrigel®. After subcutaneous implantation in rats for one week, the hydrogel enhanced neovascularization without triggering inflammatory responses. Conclusion: This study found that photo-crosslinked silk fibroin hydrogel showed pro-angiogenic and inflammation inhibitory abilities. Its photo-crosslinking ability makes it suitable for matching irregular alveolar bone defects. Thus, the photo-crosslinkable silk fibroin-derived hydrogel is a potential candidate for constructing scaffolds for alveolar bone regeneration

Progress of carbon sequestration in urban green space based on bibliometric analysis

To understand the development progress and relevant Frontier research of urban green space carbon sequestration, based on the core databases such as Web of Science, CiteSpace software, and bibliometric analysis methods were used to analyze the research status. The results showed that the number of papers on urban green space carbon sequestration research was on the rise. China and the United States had closer cooperation from the perspective of international cooperation institutions. Peking University, the Chinese Academy of Sciences, and the US Forest Service made the greatest contributions to this research field. Analyzing the keywords and the literature co-citation map, it was inferred that the hot keywords of future urban green space carbon sequestration research include carbon sequestration, ecosystem services, and climate change. It was found that carbon sequestration of urban green space ecosystems research primarily focuses on the correlation between urban green space and ecosystem services, and UGS carbon sequestration accounting and urban green space management. Finally, two perspectives were proposed: 1) Urban green spaces diversified ecological benefits are achieved through the function of carbon sequestration, and 2) Urban green space carbon sequestration accounting and urban green space management promote the development of urban green space. An overview of the international progress and basic state of urban green spaces and carbon sequestration theme research is presented in this paper, Additionally, it provides valuable references for future research and helps gain a comprehensive understanding of this field of research

Image1_Curcumin-primed periodontal ligament stem cells-derived extracellular vesicles improve osteogenic ability through the Wnt/β-catenin pathway.pdf

Introduction: Curcumin has broad application prospects in the prevention and treatment of periodontal diseases. Periodontal ligament stem cell-derived extracellular vesicles (PDLSC-EV) can effectively promote periodontal tissue regeneration and possess good drug delivery capability. Superior pharmacological effects can be exerted using PDLSC-EV as a curcumin carrier.Methods: In the present study, we constructed curcumin-primed PDLSCs-derived extracellular vesicles (Cur-PDLSC-EV) from cell culture supernatants of curcumin-pretreated PDLSCs by ultracentrifugation and investigated their effects on the proliferation, migration, and osteogenic ability of PDLSCs and the corresponding downstream molecular pathways.Results: Both Cur-PDLSC-EV and PDLSC-EV promoted osteoblast proliferation and migration. Compared with PDLSC-EV, Cur-PDLSC-EV possessed a more potent pro-osteogenic ability. Moreover, the improved osteogenesis of Cur-PDLSC-EV was related to the activation of the Wnt/β-catenin signaling pathway.Conclusion: This study suggests that Cur-PDLSC-EV can promote osteogenic differentiation by activating Wnt/β-catenin, providing reference bases for the treatment of periodontal diseases.</p

Evaluation of the Effectiveness of a Nutrient Inhibitor Applied to High Cadmium-Risk Double-Cropped Rice Fields

【Objective】The study aimed to address the conspicuous problem of excessive cadmium (Cd) in rice by developing and applying a nutrient inhibitor in the field to evaluate its effectiveness in reducing Cd uptake by rice and improving soil nutrients.【Method】One about 3.33 hm2, high-risk, double-cropped rice field was selected as a demonstration area in each of three cities in the Pearl River Delta. The nutrient inhibitor was applied to the soil before rice seedling transplanting in both the early and late cropping seasons. Its impact on the mass fraction of Cd in brown rice from different rice varieties over both cropping seasons were studied and assessed, as well as its influence on soil properties.【Result】The results showed that the nutrient inhibitor did not significantly impact the early or late cropping season rice yields in any of the three demonstration areas. However, it did reduce the mass fraction of Cd in brown rice, with reduction ranging from 8.43% to 72.5%. The nutrient inhibitor influenced soil properties differently. Compared to the control area, the nutrient inhibitor increased the pH of the soil in the double-cropped rice fields of the three demonstration areas by 0.10~0.42 units. The nutrient inhibitor increased the mass fractions of soil exchangeable calcium (Ca), magnesium (Mg), and available silicon (Si) which reached peak increases of 66.2%, 109%, and 53.0% respectively. However, the nutrient inhibitor did not noticeably change the mass fraction of soil hydrolytic nitrogen (N). In the demonstration area Ⅰ and Ⅱ, the inhibitor improved the mass fractions of available phosphorus (P) and available potassium (K) with peak increases of 78.3% and 24.6%, respectively, while in the demonstration area Ⅲ, the inhibitor insignificantly changed them. The nutrient inhibitor significantly reduced the mass fraction of available Cd in the soil in the demonstration area Ⅰ by 4.9%~7.3%, but it had no significant effect on that in the demonstration area Ⅱ and Ⅲ.【Conclusion】The nutrient inhibitor has ability to decrease the Cd accumulation in brown rice, and its impact on soil macro and moderate nutrients, and Cd bioavailability differentiates along with some conditions, while the inhibitor does not adversely affect soil properties or rice yields. Therefore, the nutrient inhibitor has the potential for safe and effective application to high-risk Cd-contaminated rice fields in the Pearl River Delta region

Interleukin-20 Acts as a Promotor of Osteoclastogenesis and Orthodontic Tooth Movement

Objectives. Bones constitute organs that are engaged in constant self-remodelling. Osteoblast and osteoclast homeostasis during remodelling contribute to overall skeletal status. Orthodontics is a clinical discipline that involves the investigation and implementation of moving teeth through the bone. The application of mechanical force to the teeth causes an imbalance between osteogenesis and osteogenesis in alveolar bone, leading to tooth movement. Osteoimmunology comprises the crosstalk between the immune and skeletal systems that regulate osteoclast–osteoblast homeostasis. Interleukin- (IL-) 20, an IL-10 family member, is regarded as a proinflammatory factor for autoimmune diseases and has been implicated in bone loss disease. However, the mechanism by which IL-20 regulates osteoclast differentiation and osteoclastogenesis activation remains unclear. This study investigated the effects of IL-20 on osteoclast differentiation in a rat model; it explored the underlying molecular mechanism in vitro and the specific effects on orthodontic tooth movement in vivo. Methods. For in vitro analyses, primary rat bone marrow-derived macrophages (BMMs) were prepared from Sprague–Dawley rats for osteoclast induction. After BMMs had been treated with combinations of recombinant IL-20 protein, siRNA, and plasmids, the expression levels of osteoclast-specific factors and signalling pathway proteins were detected through real-time polymerase chain reaction, western blotting, and immunofluorescence staining. For in vivo analyses, IL-20 was injected into the rat intraperitoneal cavity after the establishment of a rat orthodontic tooth movement (OTM) model. OTM distance was detected by Micro-CT and HE staining; the expression levels of protein were detected through immunofluorescence staining. Results. In vitro analyses showed that a low concentration of IL-20 promoted preosteoclast proliferation and osteoclastogenesis. However, a high concentration of IL-20 inhibited BMM proliferation and osteoclastogenesis. IL-20 knockdown decreased the expression of osteoclast specific-markers, while IL-20 overexpression increased the expression of osteoclast specific-markers. Furthermore, IL-20 regulated osteoclast differentiation through the OPG/RANKL/RANK pathway. Overexpression of IL-20 could significantly upregulate RANKL-mediated osteoclast differentiation and osteoclast specific-marker expression; moreover, RANKL/NF-κB/NFATc1 acted as downstream signalling molecule for IL-20. In vivo analysis showed that OTM speed was significantly increased after intraperitoneal injection of IL-20; additionally, mechanical stress sensing proteins were markedly activated. Conclusions. IL-20 augments osteoclastogenesis and osteoclast-mediated bone erosion through the RANKL/NF-κB/NFATc1 signalling pathway. IL-20 inhibition can effectively reduce osteoclast differentiation and diminish bone resorption. Furthermore, IL-20 can accelerate orthodontic tooth movement and activate mechanical stress sensing proteins

Inhibitory effects of the nanoscale lysate derived from xenogenic dental pulp stem cells in lung cancer models

Abstract Background Lung cancer is a highly prevalent malignancy and has the highest mortality rate among all tumors due to lymph node metastasis. Bone marrow and umbilical cord-derived mesenchymal stem cells (MSCs) have demonstrated tumor-suppressive effects on lung cancer. This study investigated the effects of DPSC lysate on proliferation, apoptosis, migration and invasion of cancer cells were studied in vivo and in vitro. Methods The proliferation, apoptosis, and migration/metastasis were evaluated by cell counting kit-8 assay, Annexin-V and propidium iodide staining, and the transwell assay, respectively. The expression levels of apoptosis-, cell cycle-, migration-, and adhesion-related mRNA and proteins were measured by qRT-PCR and western blot. The level and mRNA expression of tumor markers carcino embryonic antigen (CEA), neuron-specific enolase (NSE), and squamous cell carcinoma (SCC) were measured by Enzyme-linked immunosorbent assay (ELISA) and qRT-PCR. Finally, a tumor-bearing mouse model was constructed to observe the tumor-suppressive effect of DPSC lysate after intraperitoneal injection. Results DPSC lysate decreased the viability of A549 cells and induced apoptosis in lung cancer cells. Western blot confirmed that levels of Caspase-3, Bax, and Bad were increased, and Bcl-2 protein levels were decreased in A549 cells treated with DPSC lysate. In addition, DPSC lysate inhibited the migration and invasion of A549 cells; downregulated key genes of the cell cycle, migration, and adhesion; and significantly suppressed tumor markers. Xenograft results showed that DPSC lysate inhibited tumor growth and reduced tumor weight. Conclusions DPSC lysate inhibited proliferation, invasion, and metastasis; promoted apoptosis in lung cancer cells; and suppressed tumor growth- potentially providing a cell-based alternative therapy for lung cancer treatment. Graphical Abstrac

Transition from Plasmon Coupling to Plasmon-Microcavity Hybridization

International audienc

Smart ring resonator–based sensor for multicomponent chemical analysis via machine learning

We demonstrate a smart sensor for label-free multicomponent chemical analysis using a single label-free ring resonator to acquire the entire resonant spectrum of the mixture and a neural network model to predict the composition for multicomponent analysis. The smart sensor shows a high prediction accuracy with a low root-mean-squared error ranging only from 0.13 to 2.28 mg/mL. The predicted concentrations of each component in the testing dataset almost all fall within the 95% prediction bands. With its simple label-free detection strategy and high accuracy, the smart sensor promises great potential for multicomponent analysis applications in many fields.Ministry of Education (MOE)National Research Foundation (NRF)Published versio