ZnO nanoparticle-based seed priming modulates early growth and enhances physio-biochemical and metabolic profiles of fragrant rice against cadmium toxicity.

BACKGROUND: Cadmium (Cd) is amongst the most toxic heavy metals that severely affects crop growth, whereas application of nanoparticles (NPs) to negate the toxic effects of heavy metals could be an effective management approach. In the present study, the seeds of two fragrant rice varieties i.e., Yuxiangyouzhan and Xiangyaxiangzhan under normal and Cd stress conditions i.e., 0 and 100 mg L- 1 applied with four levels of ZnO NPs i.e., 0, 25, 50, and 100 mg L- 1. RESULTS: Seed priming with ZnO NPs had no significant effect on the seed germination (p > 0.05) however, it substantially improved the seedling growth and other related physiological attributes under the Cd stress. The mean fresh weight of the shoot, and whole seedling was increased by 16.92-27.88% and by 16.92-27.88% after ZnO NPs application. The root fresh weight, root-shoot length was also substantially improved under ZnO NPs treatment. Moreover, application of ZnO NPs induced modulations in physiological and biochemical attributes e.g., the superoxide dismutase (SOD) activity in root and shoot, the peroxidase (POD) activity and metallothionein contents in root were increased under low levels of ZnO NPs. The α-amylase and total amylase activity were improved by ZnO NPs application under Cd Stress. Besides, modulation in Zn concentration and ZnO NPs uptake in the seedling were detected. The metabolomic analysis indicated that various pathways such as alanine, aspartate and glutamate metabolism, phenylpropanoid biosynthesis, and taurine and hypotaurine metabolism were possibly important for rice response to ZnO NPs and Cd. CONCLUSION: Overall, application of ZnO NPs substantially improved the early growth and related physio-biochemical attributes in rice. Our findings provide new insights regarding the effects of ZnO NPs on seed germination, and early growth of rice, and its potential applications in developing crop resilience against Cd contaminated soils.

Sequentially activating macrophages M1 and M2 phenotypes by lipopolysaccharide-containing Mg-Fe layered double hydroxides coating on the Ti substrate.

As cells of innate immunity, macrophages are a class of innate immune cells existing in almost all tissues and play a crucial role in bone repair. However, it remains a challenge to modulate the sequential activation of the deferent phenotypes in macrophage when designing the titanium (Ti) implants. In this study, the Mg-Fe layered double hydroxides (LDHs) was coated on Ti substrate through hydrothermal treatment. Further on lipopolysaccharide (LPS) was introduced onto the LDHs through adsorption and ions exchange. The adsorption efficiency of the coating on LPS reached 72.8% in 24 h due to the anion exchange and electrostatic interactions between the LPS and the LDH layers in deionized water. The LDHs-LPS coating released a large amount of LPS in the early stage, which induced macrophages into M1 phenotype via activating TLR-4 → MyD88 and TLR-4 → Ticam-1/2 signal pathways. Subsequently, the M1 macrophages were transformed into M2 phenotype by regulating the integrin α5ß1 of cells by the nanostructures, wetting angle and Mg2+ of the coating. The LDHs-LPS coating endows Ti with the ability of stage immunomodulation, indicating the positive osteoimmunomodulatory property.

Highly water-stable bimetallic organic framework MgCu-MOF74 for inhibiting bacterial infection and promoting bone regeneration.

As a typical metal-organic framework (MOF), Mg-MOF74 can release biocompatible Mg2+when the framework is degraded, and it has the potential to be used as filler in the field of bone tissue engineering. However, Mg-MOF74 has poor stability in aqueous environment and limited antibacterial ability, which limit its further development and applications. In this work, MgCu-MOF74 particles with different Cu content were synthesized through a facile one-step hydrothermal method. The physicochemical properties and water stability of the synthesized powders were characterized. The osteogenic potential of the MgCu-MOF74 particles on human osteogenic sarcoma cells (SaOS-2) was evaluated. The hybrid MgCu-MOF74 exhibited favorable water stability. These results indicated that MgCu-MOF74 enhanced cellular viability, alkaline phosphatase levels, collagen (COL) synthesis and osteogenesis-related gene expression. Moreover, the samples doped with Cu2+were more sensitive to the acidic microenvironment produced by bacteria, and exhibited stronger antibacterial ability than Mg-MOF74. In conclusion, MgCu-MOF-74 with good water stability, osteogenic ability and antibacterial ability, which could be attributed to the doping of Cu2+. Hence, MgCu-MOF74 shows great potential as a novel medical bio-functional fillers for the treatment of bone defects.

Preparing Sr-containing nano-structures on micro-structured titanium alloy surface fabricated by additively manufacturing to enhance the anti-inflammation and osteogenesis.

The development of additive manufacturing technology has made it possible to customize joint implants. However, the fibrous tissue caused by long-term chronic inflammation delays bone regeneration. Moreover, the discovery of micro/nano-structure on the natural bone makes the study of implant surface morphology meaningful. In this study, a Sr-containing nano-structure on micro-structured titanium alloy surface was fabricated to enhanced the anti-inflammatory and osteogenic properties of implants. Ti6Al4V (TC4) alloys with micro-structured surface prepared by additive manufacturing were used as the material base model. Subsequently, spherical SrTiO3 particles were fabricated on the TC4 surfaces by hydrothermal treatment. The anti-inflammatory and osteogenic performance of smooth surface, micro-structured surface, Sr-containing nano-structured surface and Sr-containing micro/nano-structured surface were investigated. In vitro results exhibited that the macrophages cultured on micro/nano-structured surface were polarized to anti-inflammatory M2 phenotype and enhanced the expression of osteogenic growth factors. The Sr-containing micro/nano-structured surface effectively upgraded the proliferation and differentiation of SaOS-2 cells compared with other surfaces. Sr2+ and micro/nano-structure effectively enhanced the anti-inflammatory and osteogenic properties of titanium alloys. This finding suggested that the micro/nano-structured surface doped with bioactive elements is expected to broaden the horizons of biomedical materials. DATA AVAILABILITY: The raw/processed data required to reproduce these findings cannot be shared at this time as the data also forms part of an ongoing study.

Simultaneously stimulated osteogenesis and anti-bacteria of physically cross-linked double-network hydrogel loaded with MgO-Ag2O nanocomposites.

Hydrogels, with a three-dimensional network of water-soluble polymer and water, could simulate the critical properties of extracellular matrix, which has been widely used in bone tissue engineering. However, most of conventional hydrogels for bone regeneration are fragile and have poor osteogenic activity, which restricts their applications. In this work, a novel nanoparticle-hydrogel composite consisting of physically cross-linked double-network loaded with MgO-Ag2O nanocomposites was developed by the sol-gel method. The Mg2+ released from MgO-Ag2O nanocomposites was used as an ionic cross-linking site of sodium alginate (SA), while the hydrophobic micelles in the polyacrylamide (PAAM) network is acted as another crosslinking point. The results indicated that the novel nanoparticle-hydrogel composites had good self-recovery ability and excellent mechanical properties compared with the conventional sodium alginate (SA)/polyacrylamide (PAAM) hydrogels. Additionally, it showed a slow release of Mg and Ag ions due to the dual function of the embedding effect of hydrogels and the increasing pH of the solution induced by the hydrolysis of sodium alginate. In terms of in vitro tests, the nanoparticle-hydrogel composites showed significantly stimulatory effects on the proliferation and differentiation of SaOS-2 cells. In addition, the antibacterial effects of the nanoparticle-hydrogel composites were gradually enhanced with the increase of MgO-Ag2O content.

Sequential activation of M1 and M2 phenotypes in macrophages by Mg degradation from Ti-Mg alloy for enhanced osteogenesis.

BACKGROUND: Even though the modulatory effects of Magnisum (Mg) and its alloys on bone-healing cells have been widely investigated during the last two decades, relatively limited attention has been paid on their inflammation-modulatory properties. Understanding the activation process of macrophages in response to the dynamic degradation process of Mg as well as the relationship between macrophage phenotypes and their osteogenic potential is critical for the design and development of advanced Mg-based or Mg-incorporated biomaterials. METHODS: In this work, a Ti-0.625 Mg (wt.%) alloy fabricated by mechanical alloying (MA) and subsequent spark plasma sintering (SPS) was employed as a material model to explore the inflammatory response and osteogenic performance in vitro and in vivo by taking pure Ti as the control. The data analysis was performed following Student's t-test. RESULTS: The results revealed that the macrophages grown on the Ti-0.625 Mg alloy underwent sequential activation of M1 and M2 phenotypes during a culture period of 5 days. The initially increased environmental pH (~ 8.03) was responsible for the activation of M1 macrophages, while accumulated Mg2+ within cells contributed to the lateral M2 phenotype activation. Both M1 and M2 macrophages promoted osteoblast-like SaOS-2 cell maturation. In vivo experiment further showed the better anti-inflammatory response, regenerative potentiality and thinner fibrous tissue layer for the Ti-0.625 Mg alloy than pure Ti. CONCLUSION: The results highlighted the roles of Mg degradation in the Ti-0.625 Mg alloy on the sequential activation of macrophage phenotypes and the importance of modulating M1-to-M2 transition in macrophage phenotypes for the design and development of inflammation-modulatory biomaterials.

The response of macrophages and their osteogenic potential modulated by micro/nano-structured Ti surfaces.

Current understanding on the interactions between micro/nano-structured Ti surfaces and macrophages is still limited. In this work, TiO2 nano-structures were introduced onto acid-etched Ti surfaces by alkali-heat treatment, ion exchange and subsequent heat treatment. By adjusting the concentration of NaOH during alkali-heat treatment, nano-flakes, nano-flakes mixed with nano-wires or nano-wires could formed on acid-etched Ti surfaces. The micro- and micro/nano-structured Ti surfaces possessed similar surface chemical and phase compositions. In vitro results indicate that the morphology of macrophages was highly dependent on the morphological features of nano-structures. Nano-flakes and nano-wires were favorable to induce the formation of lamellipodia and filopodia, respectively. Compared to micro-structured Ti surface, micro/nano-structured Ti surfaces polarized macrophages to their M2 phenotype and enhanced the gene expressions of osteogenic growth factors in macrophages. The M2 polarized macrophages promoted the maturation of osteoblasts. Compared to that with nano-flakes or nano-wires, the surface with mixed features of nano-flakes and nano-wires exhibited stronger anti-inflammatory and osteo-immunomodulatory effects. The findings presented in the current work suggest that introducing micro/nano-topographies onto Ti-based implant surfaces is a promising strategy to modulate the inflammatory response and mediate osteogenesis.

Using MgO nanoparticles as a potential platform to precisely load and steadily release Ag ions for enhanced osteogenesis and bacterial killing.

Bio-functional fillers including bio-ceramic, degradable metallic and composite particles are commonly introduced into bone tissue engineering (BTE) scaffolds to endow the materials with specific biological functions for enhanced bone defect therapy. In this work, MgO nanoparticles (NPs) were employed as a potential platform for precise loading and sustained release of Ag+. The results showed that MgO NPs possessed strong adsorption capacity (almost 100%) towards Ag+ in AgNO3 solutions with different concentrations (0.1, 1 and 10 mM). After the adsorption of Ag+ in AgNO3 solutions, cube-shaped MgO NPs transformed to lamella-structured nano-composites (NCs) composed of Mg(OH)2 and Ag2O, which were referred as MgO-xAg (x = 0.1, 1 or 10) NCs depending on the employed concentration of AgNO3 solution. After being suspended in distilled water, as-prepared positively charged NCs underwent a fast degradation process during the initial 4 days. From day 4 and 14, steady release behaviors of Mg2+ and/or Ag+ from the NCs were noticed. With the lowest loading amount of Ag+, MgO-0.1Ag NCs did not exhibit significant modulatory effect on SaOS-2 cell response. On the contrary, MgO-10Ag NCs loaded with the highest amount of Ag+ showed significant cyto-toxicity towards SaOS-2 cells. With appropriate amount of Ag+ loading, MgO-1Ag NCs showed significantly stimulatory effects on SaOS-2 cell proliferation and differentiation. This is evidenced by the enhanced cell viability, alkaline phosphatase (ALP) activity and collagen (COL) production as well as the gene expressions of ALP, COL and osteoprotegerin (OPG) in MgO-1Ag group. Moreover, MgO-1Ag exhibited strong bactericidal capacity against both Escherichia coli and Staphylococcus aureus. Together, the results indicate that MgO could be employed as a potential platform for precise loading and sustained release of Ag+. MgO-1Ag NCs are promising to be used as bio-functional fillers in BTE scaffolds for simultaneously promoted osteogenesis and bacterial killing.

Stimulation of in vitro and in vivo osteogenesis by Ti-Mg alloys with the sustained-release function of magnesium ions.

Magnesium (Mg) is well-known for its bioactivity and degradability. However, due to its low evaporation temperature and limited solubility in titanium (Ti), the fabrication of Ti-Mg alloys remains a huge challenge. In this study, Ti-xMg (x = 0.312, 0.625, 1.25 and 2.5 wt.%) alloys were fabricated by the combination of mechanical alloying (MA) and spark plasma sintering (SPS). Mg mainly existed as a solid solute element in the Ti matrix, while it also existed as second-phase particles due to its precipitation and dispersion during the SPS process. At a low content of 0.625 wt.%, Mg could increase the mechanical strength of Ti by the solid solution strengthening. However, it was detrimental to material mechanical properties when the Mg content increased to 1.25 wt.%. Being immersed in phosphate buffered solution (PBS), Ti-Mg alloys exhibited a burst Mg2+ release behavior within the first day, and then the rates of Mg2+ release gradually decreased within the following 27 days. The results suggested that the cell viability was dependent on the content of Mg in the Ti-Mg alloys. The high Mg content (2.5 wt.%) in the Ti-Mg alloys could lead to significant cytotoxicity. However, appropriate Mg content (0.312∼0.625 wt.%) could promote cell attachment, proliferation and differentiation. The Ti-0.625Mg alloy exhibited the best in vitro biological performance among all groups. In vivo results obtained by implanting the Ti-0.625Mg alloy in the femurs of rats further revealed its enhanced regenerative potential and osteointegration compared to pure Ti implants.

Light and water treatment during the early grain filling stage regulates yield and aroma formation in aromatic rice.

The effect of light and water on aromatic rice remain largely unclear. A pot experiment was conducted to investigate the influences of light-water treatments (CK: natural light and well-watered conditions, WS: natural light and water-stressed conditions, LL: low light and well-watered conditions, LL-WS: low light and water-stressed treatment) on yield and 2-acetyl-1-pyrroline (2AP) formation in aromatic rice. Compared with CK, the light-water treatments decreased grain yield (10.32-39.19%) due to reductions in the filled grain percentage and total dry weight, in the regulation of biomass distribution, and in the attributes of gas exchange and antioxidant response parameters. The 2AP content in grains increased in the LL treatment (5.08-16.32%) but decreased in the WS treatment compared with that in CK. The changes in 2AP were associated with changes in 2AP formation-related traits and element content. Low light and water stress led to yield declines in aromatic rice, but low light alleviated the decrease in 2AP content caused by water stress.

The prognostic significance of fibroblast activation protein-α in human lung adenocarcinoma.

BACKGROUND: Fibroblast activation protein (FAP) is a type II cell surface-bound integral serine protease, which is an important biomarker of cancer-associated fibroblasts. FAP-α performs several biological activities, including remolding extracellular matrix and acting as an immunosuppressor in the tumor microenvironment. However, the proliferation role of FAP-α in human lung adenocarcinoma has not been fully elucidated. METHODS: The expression of FAP-α in 94-paired human lung adenocarcinoma tissues was identified by immunohistochemistry test. The effect of FAP on cell proliferation was examined by CCK-8 assay. RNA-sequencing and bioinformatics analysis were utilized to investigate the underlying mechanism. Western blot analysis, quantitative polymerase chain reaction (qPCR), and nude mice experiments, were also conducted for further validation. RESULTS: The proliferation rates of human fibroblast strains FAP-HFF and FAP-BJ, and human lung adenocarcinoma cell line FAP-SPC-A-1 were higher than those of controls. The nude mice experiment also showed that FAP could promote the proliferation of SPC-A-1 cell line in vivo. qPCR and Western blot analysis indicated that CCNB1 was upregulated by the overexpression of FAP in the lung adenocarcinoma cell line. The expression of FAP-α was higher in both the cytoplasm and stroma of lung adenocarcinoma than in adjacent normal tissues. Survival analysis indicated that patients with higher expression of FAP-α in tumor stroma had a poor prognosis (P=0.019). The Cancer Genome Atlas Program (TCGA) data also showed that the expression of FAP within tumor tissues was higher (in both cytoplasm and stroma) compared with that in normal tissues (P<0.05). CONCLUSIONS: Our study indicates that FAP-α could facilitate the proliferation of lung adenocarcinoma cells and can be a prognostic marker in human lung adenocarcinoma.

Up-regulation of S100A4 expression by HBx protein promotes proliferation of hepatocellular carcinoma cells and its correlation with clinical survival.

BACKGROUND: Hepatocellular carcinoma is one of the most common cancers worldwide. HBV-related HCC has characteristics of faster progression and worse prognosis. Previous studies have confirmed that HBx protein plays numbers of important roles in development of HBV-HCC. However, the molecular mechanism of carcinogenicity of HBx is still not well documented. METHODS: Firstly, a HCC cell line over-expressing HBx was established and its function was verified. Subsequently, the differentially expressed genes were detected by transcriptome sequencing technology and use the Western Blot technology to detect the up-regulated genes in HBx overexpressed cells, and the functional correlation of the genes was analyzed. Finally, tissue microarray was used to correlate up-regulated gene with clinical follow-up data to verify correlation with clinical prognosis. RESULTS: Over-expression of HBx could promote cell proliferation, and over-expression of HBx could up-regulate the expression of S100A4 protein. ShRNA experiments showed that HBx promoted cell proliferation by upregulating the expression of S100A4. IFN-α2b can down-regulate the expression of S100A4 and inhibit the proliferation of HCC cells. The expression of S100A4 in cancer was significantly up-regulated compared with adjacent tissues, and was also significantly associated with tumors volume, the expression of PD-L1 and the survival time of patients with HCC. CONCLUSION: In general, S100A4 may be an effective therapeutic target for HBV-HCC. And the connection between S100A4 and HBV are not clear yet. This study may play a guiding role in the future clinical treatment of HCC.

Powder metallurgical Ti-Mg metal-metal composites facilitate osteoconduction and osseointegration for orthopedic application.

In this work, Ti-Mg metal-metal composites (MMCs) were successfully fabricated by spark plasma sintering (SPS). In vitro, the proliferation and differentiation of SaOS-2 cells in response to Ti-Mg metal-metal composites (MMCs) were investigated. In vivo, a rat model with femur condyle defect was employed, and Ti-Mg MMCs implants were embedded into the femur condyles. Results showed that Ti-Mg MMCs exhibited enhanced cytocompatibility to SaOS-2 cells than pure Ti. The micro-computed tomography (Micro-CT) results showed that the volume of bone trabecula was significantly more abundant around Ti-Mg implants than around Ti implants, indicating that more active new-bone formed around Ti-Mg MMCs implants. Hematoxylin-eosin (H&E) staining analysis revealed significantly greater osteointegration around Ti-Mg implants than that around Ti implants.

The glucose-6-phosphate dehydrogenase Mahidol variant protects against uncomplicated Plasmodium vivax infection and reduces disease severity in a Kachin population from northeast Myanmar.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common red cell disorders in the world. The aim of this study was to investigate whether the G6PD Mahidol variant and haplotype 1311 T/93C, which are prevalent in the Kachin ethnic population along the China-Myanmar border area, offer protection against Plasmodium vivax infection. Malaria was monitored in nine villages near the Laiza township, Kachin State, Myanmar, where 258 cases of uncomplicated P. vivax were identified in 2013-2017. From the same villages, 250 unrelated, malaria-free participants were recruited to serve as the control cohort. Quantitative enzyme activity analysis in 100 healthy individuals identified that both male hemizygotes and female heterozygotes of the G6PD Mahidol variant had on average ~40% lower enzyme activity relative to the wild-type individuals. Compared with the overall prevalence of 25.2% in the control cohort, the G6PD Mahidol variant had a significantly lower prevalence (7.0%) among the 258 vivax patients (P <  .0001, χ2 test). Logistic regression analysis of G6PD genotypes stratified by sex showed that the individuals with the Mahidol 487A allele had dramatically reduced odds of having acute vivax malaria (adjusted odds ratio = 0.213 for male 487A hemizygotes, P < .0001, and 0.248 for female 487GA heterozygotes, P < .001). Furthermore, both 487A hemizygous male and 487GA heterozygous female patients had significantly lower asexual parasitemias than the wild-type patients, suggesting a potential effect on alleviating disease severity. In contrast, the silent mutation haplotype 1311 T/93C was highly prevalent (49.6%) in the study population, but it was not associated with altered G6PD enzymatic activities nor did it seem to provide protection against vivax infection or disease severity. Taken together, this study provided evidence that the Mahidol G > A mutation offers protection against P. vivax infection and potentially reduces disease severity in a Kachin population.