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Hydrogels are extracellular-matrix-like biomimetic materials that have wide biomedical applications in tissue engineering and drug delivery. However, most hydrogels cannot simultaneously fulfill the mechanical and cell compatibility requirements. In the present study, we prepared a semi-interpenetrating network composite gel (CG) by incorporating short chain chitosan (CS) into a covalent tetra-armed poly(ethylene glycol) network. In addition to satisfying physicochemical, mechanics, biocompatibility, and cell affinity requirements, this CG easily encapsulated acetylsalicylic acid (ASA) via electrostatic interactions and chain entanglement, achieving sustained release for over 14 days and thus promoting periodontal ligament stem cell (PDLSC) proliferation and osteogenic differentiation. In vivo studies corroborated the capacity of PDLSCs and ASA-laden CG to enhance new bone regeneration in situ using a mouse calvarial bone defect model. This might be attributed to PDLSCs and host mesenchymal stem cells expressing monocyte chemoattractant protein-1, which upregulated M2 macrophage recruitment and polarization in situ, indicating its appealing potential in bone tissue engineering., Graphical abstract Image 1, Highlights • A facile method to prepare the composite gels with advantages of easy operation, good biocompatibility and biodegradability. • Composite gels can simultaneously fulfill the mechanical strength and cell-compatibility requirements. • Composite gels can achieve the loading and sustained release of acetylsalicylic acid via electrostatic interaction and chain entanglement. • Acetylsalicylic-acid-encapsulated composite gel is paramount to promote PDLSCs-mediated bone regeneration. • The underlying mechanism might be associated with upregulation of MCP-1 and macrophage M2 polarization.

Zenghou Yi Tomb (433 BC) in the early Warring States Period of China is a very important archaeological discovery. Lots of lacquerware was unearthed here, typically representative of that from Chu in the Warring States Period. This article presents analyses of the lacquered inner coffin and a lacquered zither from the tomb, and their surface is red lacquer, supplemented by additional black and yellow patterns. Yellow painted lacquerware remains relatively rare from this period and therefore deserves further study. Numerous methods including three-dimensional (3D) video microscopy and scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), pyrolysis-gas chromatography/mass spectroscopy (Py-GC/MS), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy as well as enzyme-linked immunoassay (ELISA) were adopted to analyze the lacquer and pigments from the two artifacts. The results of this study reveal that lacquer samples from both the two artifacts have multilayered structures and contained added eggs and oil. The red pigment on the lacquer surface was made of cinnabar mixed with lacquer, the black one was carbon black mixed with lacquer, while the yellow one was pararealgar mixed with gelatin. These differences may explain the relative rarity of yellow painted lacquerware from early periods.

Bone defects caused by injury, disease, or congenital deformity remain a major health concern, and efficiently regenerating bone is a prominent clinical demand worldwide. However, bone regeneration is an intricate process that requires concerted participation of both cells and bioactive factors. Mimicking physiological bone healing procedures, the sustained release of bioactive molecules plays a vital role in creating an optimal osteogenic microenvironment and achieving promising bone repair outcomes. The utilization of biomaterial scaffolds can positively affect the osteogenesis process by integrating cells with bioactive factors in a proper way. A high water content, tunable physio-mechanical properties, and diverse synthetic strategies make hydrogels ideal cell carriers and controlled drug release reservoirs. Herein, we reviewed the current advancements in hydrogel-based drug sustained release systems that have delivered osteogenesis-inducing peptides, nucleic acids, and other bioactive molecules in bone tissue engineering (BTE).

RNA interference (RNAi) is an efficient post-transcriptional gene modulation strategy mediated by small interfering RNAs (siRNAs) and microRNAs (miRNAs). Since its discovery, RNAi has been utilized extensively to diagnose and treat diseases at both the cellular and molecular levels. However, the application of RNAi therapies in bone regeneration has not progressed to clinical trials. One of the major challenges for RNAi therapies is the lack of efficient and safe delivery vehicles that can actualize sustained release of RNA molecules at the target bone defect site and in surrounding cells. One promising approach to achieve these requirements is encapsulating RNAi molecules into hydrogels for delivery, which enables the nucleic acids to be delivered as RNA conjugates or within nanoparticles. Herein, we reviewed recent investigations into RNAi therapies for bone regeneration where RNA delivery was performed by hydrogels.

Divanillic acid, the dimer of vanillic acid, has been widely used as an aromatic building block of bio-based polymers. In this study, a series of homo- and copolyesters composed of a methylated dialkoxydivanillic acid monomer with an alkoxy side-chain length of 1 or 4 carbon units, cyclohexanedimethanol, and an alkanediol with a chain length of 6, 8, or 12 carbon units was synthesized. The polyesters obtained exhibited high weight-average molecular weights in the range of 4.4 × 104 to 20 × 104 g/mol and degradation temperatures higher than 380 °C. Thermo-pressed films were prepared from all the polyesters. Their glass transition temperature and elongation-at-break values could be tuned from −1 to 120 °C and 3% to 1500%, respectively, by changing the lengths of the alkoxy side chain and the alkanediol as well as the composition of the copolyester.

Divanillic acid (DVA)–based monomers with different side-chains (R = -(CH2)n-1-CH3, n = 1, 4, 8) were synthesized from methyl vanillate. Polycondensation of these monomers with various aromatic diamines yielded a series of aromatic biomass-based polyamides with weight-average molecular weights (Mw) ranging from 50,000 to 110,000 g/mol. Thermogravimetric analysis (TGA) of the polyamides found decomposition temperatures ranging from 378 to 420 °C. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) revealed an amorphous structure. The polyamides with methyl or butyl side chains exhibited a glass transition temperature (Tg) of 221–322 °C, which indicated high heat resistance and thermal stability, while the Tgs of the polyamides with octyl side chains were about 180 °C. The DVA polyamides showed good solubility in common polar organic solvents; their cast films were prepared from dimethylformamide (DMF) solution. Thermo-pressed films of some polyamides were prepared at temperatures over the Tg, revealing maximum tensile strengths of about 63 MPa.

A new and simple method was established to prepare polyamides with a chelating feature through Michael addition and polycondensation. A piperazine-diester monomer, that is, N,N´-bis(methyl propanoate) piperazine (BMPZ), was synthesized through a Michael addition of piperazine and methyl acrylate. Three polyamides containing piperazine rings (PIP-PAs) were synthesized via melt polycondensation from BMPZ and different diamines. PIP-PAs were modified by chelating Co2+, and several PIP-PA-Co2+ complexes were obtained. The structure of BMPZ and PIP-PAs was characterized by FT-IR and 1H NMR spectra. DSC and wide angle X-ray diffraction verified the crystallizable feature of PIP-PAs. They possessed Tm from 81 °C to 171 °C, tensile strength up to 31 MPa, and good toughness. Chelating PIP-PAs with Co2+ was accompanied by color change and the loss of crystallization. The effect of chelation on Tg, tensile strength, and Young's modulus was investigated. Polyamide complexes with good mechanical property and solvatochromic feature were synthesized successfully.

In this paper, we demonstrated ytterbium-doped mode-locked fiber lasers based on saturable absorbers (SAs) made of few-layer black phosphorus (BP) with all normal dispersion. The few-layer BP was prepared with the liquid phase exfoliation method and was deposited onto fiber facets by an optically driven process. By incorporating the BP-SA into an ytterbium-doped fiber cavity, stable mode-locking laser operation in all-normal dispersion region was achieved with a repetition rate of 46.3 MHz. The laser spectrum was centered at 1030.6 nm with a 3 dB bandwidth of 0.11 nm. Maximum output power of 32.5 mW was achieved and showing no signs of saturation.

Bone defects, massive bone defects in particular, is still an issue clinically. Acetylsalicylic acid (ASA), also known as aspirin, has been proven to be conducive for mesenchymal stem cells osteogenic differentiation, which may be benefited for bone regeneration. In order to achieve a more appealing prognosis of bone defect, here we develop a well-defined tetra-PEG hydrogel sealant with rapid gelation speed, strong tissue adhesion, and high mechanical strength. After in-situ encapsulation of aspirin, this drug-loaded tetra-PEG hydrogel possessed a sustained release, anti-inflammation, and osteoinductive properties. In vitro experiments showed that the cell proliferation was slightly facilitated, and the osteogenic differentiation was notably augmented when periodontal ligament stem cells (PDLSCs) were co-incubating with the hydrogel materials. Moreover, in vivo study manifested that the aspirin sustained release system significantly facilitated the PDLSCs mediated bone defect regeneration. Overall, tetra-PEG hydrogel-based aspirin sustained release system is applicable not only for enhancing the osteogenesis capacity of PDLSC but also providing a new thought of bone regenerative therapy.

The p53 pathway is a highly complex signaling network including several key regulators. HAUSP is a critical component of the p53 pathway acting as a deubiquitinase for both p53 and its key repressor Mdm2. Here, we identified a novel HAUSP-interacting protein, HLA-B-associated transcript 3 (Bat3) and found it to be capable of inducing p53 stabilization and activation via a HAUSP-dependent mechanism, resulting in cell growth inhibition. Surprisingly, the deubiquitylating enzymatic activity of HAUSP was not required for this phenomenon. Co-immunoprecipitation showed that p53 coexisted in a complex with Bat3 and HAUSP in vivo, and HAUSP may serve as a binding mediator to enhance the interaction between p53 and Bat3. Further studies revealed that formation of this three-protein complex interfered with the binding of p53 to its proteasome receptor S5a and promoted the accumulation of p53 in nucleus. Notably, Mdm2 protein abundance is also regulated by Bat3 in the presence of HAUSP. Overexpression of Bat3 and HAUSP increases Mdm2 protein levels without influencing the p53–Mdm2 interaction and Mdm2-mediated p53 ubiquitination, indicating that Bat3–HAUSP-mediated protein stabilization is not specific to p53 and different mechanisms may be involved in Bat3-mediated regulation of p53–Mdm2 pathway. Together, our study unravels a novel mechanism by which p53 is stabilized and activated by HAUSP-mediated interaction with Bat3 and implies that Bat3 might function as a tumor suppressor through the stabilization of p53.

This work synthesized a series of symmetrical methylated dialkoxydivanillic acid monomers (Me-RDVAs) with different side-chain lengths (meaning the number of carbons, n, in alkoxy groups, where n = 1, 2, 3 or 4) and methyl (Me), ethyl, propyl or butyl R groups. Homopolyesters were obtained from Me-RDVAs and 1,4-benzenedimethanol, 1,4-cyclohexanedimethanol and 4,4ʹ-biphenyldimethanol, with the aim of producing improved thermal properties. Copolyesters composed of Me-MeDVA together with aliphatic linear diols and cyclic diols were also synthesized. The weight average molecular weights of the resulting polyesters ranged from 1.5 to 11.0 × 104 g/mol and all were thermally stable. Glass transition temperatures varied from 58 to 134 °C. A semi-crystalline polyester with a high melting point of 220 °C was obtained from Me-MeDVA and trans-1,4-cyclohexanedimethanol, and was assessed using polarized optical microscopy and one-dimensional wide-angle X-ray diffraction. Self-standing films of several high molecular weight polyesters were prepared and their mechanical properties assessed.

This review article comprehensively discusses the recent development of various environmental applications of Zinc Oxide (ZnO) semiconductor materials. The synthesis of various nano/micro structured ZnO using different methods and the influence of various preparation conditions on ZnO morphology are discussed. The environmental applications of nano/micro structured zinc oxide as an adsorbent, photocatalyst, and catalyst in catalytic ozonation processes are discussed. The adsorption of various organic pollutants and metal ions on the ZnO surface at different conditions are discussed. The ZnO assisted photocatalytic degradation of pollutants, water splitting, and disinfection under various conditions are reported on. Ozonation in the presence of zinc oxide and its influence on the removal of pollutants are also included.

In this paper, polyaniline-coated silver phosphate has been successfully prepared via a facile chemisorption method in order to improve the stability of Ag3PO4 under light irradiation. The crystalline phase, band gap energy, and microstructure of the obtained PANI/Ag3PO4 composites were characterized by X-ray diffraction, UV–vis diffuse reflection spectroscopy, scanning electron microscopy, and transmission electron microscopy, respectively. The photocatalytic degradation of methlylene blue was performed to test the activities of PANI/Ag3PO4 composites with different coating amounts and the results indicate that the stabilities of PANI/Ag3PO4 composites were successfully enhanced. The correlation between photocatalytic performance and the properties of PANI/Ag3PO4 composites is discussed in detail.

Nano-sized BiPO 4 has been successfully synthesized via a novel designed two-steps solvothermal route using ethylene glycol as solvent. Comparing with traditional hydrothermal method, the novel approach could readily prepare BiPO 4 with shorter time. The photocatalytic activity of prepared BiPO 4 has been tested via degradation of methylene blue (MB) under light irradiation. The experimental results show that the BiPO 4 prepared by novel route had enhanced photocatalytic activity and the synthetic parameters also impact the reaction rate meaningfully. Finally, the obtained samples have been widely characterized by means of powder X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area, scanning electron microscopy (SEM), UV–vis diffuse reflectance spectra (DRS) and Fourier transformed infrared (FTIR) spectra. BiPO 4 prepared by this novel approach have a particles size below 100 nm, which is a big improvement by comparing with previous works (few micrometer). The effect of EG during the formation of BiPO 4 has been discussed and a possible formation mechanism is proposed.

Visible light-activated photocatalyst calcium indate (CaIn2O4) has been successfully prepared by a new approach with lower temperature calcinations. The sub-micrometer-sized samples were characterized by X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and UV-vis diffuse reflectance spectroscopy. High-purity CaIn2O4 particles were synthesized by controlling the sintering temperature and their photocatalytic performance were evaluated. Under visible light irradiation, 10 ppm of methylene blue solution was effectively degraded in 3.0 h. The excellent photocatalytic activity of CaIn2O4 is attributed to the high purity, small particle size, and large surface area because of lower sintering temperature by thermal decomposition of metal oxalate precursor.

The photocatalytic mineralization of phenol was investigated in the presence of BiPO4 prepared by hydrothermal method. The crystal structure and morphology of synthesized sample was inspected with powder X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The photocatalytic activity of BiPO4 was evaluated by the degradation of phenol in a batch reactor under UV-C irradiation. In order to investigate the influence of catalyst dosage, pH value, initial concentration and additives on mineralization behavior, these key operating parameters were systematically changed during the photocatalytic process. The findings confirmed that the phenol was degraded by BiPO4 under UV-C irradiation, and the TOC (Total Organic Carbon) analysis proved that the mineralization was efficient under the optimized conditions. It is also found that the intermediate process between photocatalytic degradation and mineralization is negligibly short.

In this work we introduce recently developed silicon-paste-enabled p-type doping for silicon. Boron-doped silicon nanoparticles are synthesized by a plasma approach. They are then dispersed in solvents to form silicon paste. Silicon paste is screen-printed at the surface of silicon wafers. By annealing, boron atoms in silicon paste diffuse into silicon wafers. Chemical analysis is employed to obtain the concentrations of boron in silicon nanoparticles. The successful doping of silicon wafers with boron is evidenced by secondary ion mass spectroscopy (SIMS) and sheet resistance measurements.

This study analyzed the influence of substance P (SP) on growth factors related to wound healing in mice in the presence of infectious keratitis.Naturally resistant mice were injected intraperitoneally with SP or phosphate-buffered saline and infected with Pseudomonas aeruginosa, and corneal messenger RNA (mRNA) levels of growth factors and apoptosis genes were tested. Enzyme-linked immunosorbent assay determined the protein levels, whereas immunohistochemistry tested the distribution, macrophage phenotype, and cell quantitation. In vitro, macrophages were stimulated with lipopolysaccharide (LPS; with or without SP) and mRNA levels of proinflammatory and antiinflammatory cytokines and apoptosis genes were tested.After SP, epidermal growth factor mRNA and protein levels were disparately regulated early, with no differences later in the disease. Hepatocyte growth factor and fibroblast growth factor-7 mRNA and protein levels were increased after SP treatment. Enumerating dual-labeled stromal cells revealed no difference between SP-treated versus phosphate-buffered saline-treated groups in the percentage of epidermal growth factor-labeled fibroblasts or macrophages, but there were significant increases in both hepatocyte growth factor- and fibroblast growth factor-7-labeled cells. Type 2 (M2) macrophages and caspase-3 mRNA levels were decreased, whereas B-cell lymphoma-2 mRNA expression was increased after SP treatment. In vitro, mRNA levels of several proinflammatory cytokines and B-cell lymphoma-2 were elevated, whereas transforming growth factor β was decreased after macrophage stimulation with SP (with LPS) over LPS alone. (Mice: n = 105 control; 105 experimental.)These data show that treatment with SP in infectious keratitis elevates growth factors but also adversely affects the disease by enhancing the inflammatory response and its sequelae.

PURPOSE: Apoptosis was examined after Pseudomonas aeruginosa corneal infection in C57BL/6 (B6, susceptible) and BALB/c (resistant) mice. METHODS: TUNEL staining, real-time RT-PCR, polymorphonuclear neutrophils (PMNs) and macrophage (Mphi) depletion, and immunostaining were used. RESULTS: Intense TUNEL staining was seen in BALB/c versus B6 cornea at 1 versus 3 days after infection (PI) and correlated with mRNA levels for caspase-3. TUNEL staining (with or without PMN depletion) and PMN immunostaining revealed the PMN as the major apoptotic cell for both groups. Next, B6 mice with high corneal levels of the antiapoptosis neuropeptide, substance P (SP), were treated with the SP antagonist, Spantide I (with/without Mphi depletion), resulting in earlier apoptosis and diminished disease only when M(phi)s were present. SP interactions with M(phi)s were explored further by eliciting cells from both groups and stimulating them with lipopolysaccharide (LPS), with or without SP. LPS with SP treatment decreased the number of apoptotic M(phi)s in B6 but not BALB/c mice and correlated with reduced mRNA expression of NK-1R (major SP receptor) on BALB/c cells. In addition, mRNA expression for IL-12 was upregulated in LPS-stimulated B6 M(phi)s, although cells from BALB/c mice expressed more IL-10. CONCLUSIONS: These studies provide evidence that PMN apoptosis is delayed in the cornea of B6 versus BALB/c mice after bacterial infection; that in B6 mice, blocking SP interaction with the NK-1R promotes earlier apoptosis and improves disease outcome; that M(phi)s regulate PMN apoptosis; and that M(phi)s from B6 versus BALB/c mice differ in expression of the NK-1R and cytokines produced after LPS challenge.

Purpose To determine the effects of blocking substance P (SP) interactions with its major receptor (NK1-R) using the antagonist spantide I in susceptible mice infected with Pseudomonas aeruginosa. Methods Immunohistochemistry and enzyme immunosorbent assay (EIA) tested levels of SP in the cornea of B6 and BALB/c mice. B6 mice were treated with spantide, and after infection, slit lamp examination; clinical score; bacterial counts; and myeloperoxidase (MPO), RT-PCR, ELISA, and polymorphonuclear (PMN) cell chemotaxis assays were performed. Results SP corneal levels were significantly elevated constitutively and after infection in the B6 more than in BALB/c mice. Spantide treatment of B6 mice significantly decreased the number of perforated corneas, bacterial counts, and PMNs. mRNA levels for type I cytokines (e.g., IFN-gamma) as well as MIP-2, IL-6, TNF-alpha, and IL-1beta (mRNA and protein) also were significantly reduced after spantide treatment. The type II cytokine IL-10 (mRNA and protein) was elevated, whereas TGF-beta mRNA levels were unchanged after spantide treatment. PMN chemotaxis was induced by SP and other neuropeptides in vitro, but was not affected by spantide I. mRNA for neurokinin-1-receptor-1 (NK-1R) was detected in the normal and infected corneas and on macrophages (Mphis), but not on PMNs (unstimulated or stimulated with endotoxin [LPS]). Spantide treatment of Mphis reduced IL-1beta after LPS+SP treatment but not after either alone. Conclusions The SP antagonist Spantide provides a novel approach to reduce type 1 and enhance the type 2 cytokine IL-10 in the infected cornea of B6 mice, leading to a significant reduction in corneal perforation and improved disease outcome.

Purpose Studies have shown that blocking substance P (SP) binding to neurokinin 1 receptor with spantide I prevents Pseudomonas aeruginosa-induced corneal perforation in susceptible C57BL/6 mice. This study tested the effect of SP injection on the resistance response (cornea heals) of BALB/c mice. Methods The day before infection, mice were injected intraperitoneally with SP or PBS. Disease was graded by clinical score, slit lamp, plate count, real-time RT-PCR, and ELISA assays, and polymorphonuclear neutrophils (PMNs) were quantitated using a myeloperoxidase assay. In additional experiments, BALB/c mice were injected intraperitoneally with vasoactive intestinal peptide (VIP) antagonist and similarly analyzed. Results Mice injected with SP exhibited worsened disease on days 1 to 7 after infection compared with controls. SP injection resulted in elevated PMN levels and viable bacterial counts in the cornea 3 and 5 days after infection. mRNA expression for NFkappaB and type 1 cytokines (e.g., IFN-gamma), as well as for TNF-alpha, MIP-2, IL-18, IL-6, and IL-1beta, were significantly elevated, whereas VIP and cytokines TGF-beta and IL-10 were significantly reduced. Differences in mRNA expression were selectively confirmed at the protein level by ELISA for NFkappaB, IL-1beta, and IL-10. VIP antagonist treatment also resulted in exacerbated disease scores, elevated proinflammatory mediators, and reduced anti-inflammatory mediators. Conclusions These data provide evidence that the neuropeptide SP, among its broad systemic effects, is a potent neuroimmunoregulator that promotes susceptibility in the resistant BALB/c mouse by overcoming the anti-inflammatory effects of VIP and IL-10 and that a balance between SP and VIP levels may be critical in disease resolution.

Background Zinc plays important roles in maintaining normal function of the prostate and in development of prostate malignancy. It has been demonstrated that prostate malignant epithelial cells contain much less cellular zinc than the surrounding normal epithelial cells. However, the pathway(s) which leads to lower zinc accumulation in malignant prostate epithelial cells is poorly understood. In this study, the zinc homeostatic features of two human prostate epithelial cell lines (non-tumorigenic, RWPE1, and tumorigenic, RWPE2) were investigated. Effects of over-expression of ZIP1 in RWPE2 on cell proliferation and apoptosis were also studied. Results RWPE2 accumulated less intracellular zinc than RWPE1 due to the decreased zinc uptake activity. The mRNA expression of ZIP1 and ZIP3 in RWPE1 and RWPE2 was comparable. However, the protein expression of ZIP1 in RWPE2 was lower than that in RWPE1. ZIP3 was detected in a lysosomal compartment of RWPE2 while no ZIP3 was detected in the same compartment of RWPE1. Over-expression of ZIP1 in RWPE2 resulted in an elevation of intracellular zinc concentration and suppression of cell growth of RWPE2 due to the increased apoptosis. Conclusion These findings suggest that tumorigenic prostate epithelial cells accumulated less intracellular zinc than non-tumorigenic prostate epithelial cells. The reduction in capacity for accumulation of intracellular zinc in tumorigenic prostate epithelial cells may be caused by the decrease in the ZIP1 protein expression and the intracellular redistribution of ZIP3 in RWPE2. RWPE1 and RWPE2 are excellent cellular models to study the association of intracellular zinc levels with prostate cancer progression.