Alendronate promotes the gene expression of extracellular matrix mediated by SP-1/SOX-9

BACKGROUND AND PURPOSE

Osteoarthritis (OA) is a disease with significant degenerative changes of articular cartilage, which is reported to be closely related to the integrity of chondrocytes extracellular matrix (ECM). Alendronate belongs to the family of bisphosphonates with promising cartilage repair function. In the present study, the effects of Alendronate on the gene expression of chondrocytes ECM and the potential mechanism will be investigated to explore the potential therapeutic property of Alendronate on OA.

METHODS

Human SW1353 chondrocytes were stimulated with 1 and 2 μM Alendronate for 12 h. The gene expression of Col2α1, COL9α2, and Acan in the treated chondrocytes was determined by qRT-PCR. QRT-PCR and western blot analysis were used to evaluate the expression level of SOX-9 in the treated chondrocytes. The expression level of SP-1 was checked by qRT-PCR and immunostaining. SiRNA against SP-1 was transfected into chondrocytes to knockdown the expression of SP-1. The levels of p-ERK1/2 and total ERK1/2 were examined using western blot analysis. TNF-α was used to induce an OA-like in vitro model in the chondrocytes for therapeutic evaluations.

RESULTS

Treatment with Alendronate increased the levels of ECM related genes (Col2α1, COL9α2, and Acan) in a dose-dependent manner through increasing the expression of SOX-9, a central regulator of ECM genes. Additionally, our findings demonstrate that the effects of Alendronate in the expression of SOX-9 are mediated by SP-1 as silencing of SP-1 abolished these effects. Notably, Alendronate increased the phosphorylation of ERK1/2 and inhibition of ERK1/2 using its specific inhibitor U0126 blocked the expression of SP-1. Finally, we found that treatment with Alendronate could rescue TNF-α-induced reduction of Col2α1, COL9α2, Acan and SOX-9.

CONCLUSION

Our data indicated that Alendronate might promote the gene expression of extracellular matrix through SOX-9 mediated by the ERK1/2/SP1 signaling pathway.

Investigating the co-firing characteristics of bamboo wastes and coal through cone calorimetry and thermogravimetric analysis coupled with Fourier transform infrared spectroscopy

To evaluate the combustion characteristics of raw or torrefied bamboo wastes and coal blends, the co-firing process determined by cone and pollutant emission was investigated by thermogravimetric analysis coupled with Fourier transform infrared spectroscopy. The results showed that torrefaction improved the fuel properties of bamboo wastes. Torrefied bamboo had a lower volatile fuel ratio, H/C and O/C ratios, pollutant emission and a higher heating value. They further affected the co-firing process of raw or torrefied bamboo and coal. All blends had a lower ignition temperature and a more stable flame than coal. Torrefied bamboo and coal blends had a lower percentage of quality loss, a higher heat release rate (HRR), total heat release (THR) and total smoke release (TSR). With an increase in the proportion of torrefied bamboo in the blends, the HRR, THR, TSR and percentage of quality loss increased. The main pollutant emissions included CO₂, CO, SO₂ and NO_x. All blends of torrefied bamboo and coal had a lower pollutant emission. The optimum blend suggested was 20% torrefied bamboo/80% coal.

Nitrogen Self-Doped Activated Carbons Derived from Bamboo Shoots as Adsorbent for Methylene Blue Adsorption

Bamboo shoots, a promising renewable biomass, mainly consist of carbohydrates and other nitrogen-related compounds, such as proteins, amino acids and nucleotides. In this work, nitrogen self-doped activated carbons derived from bamboo shoots were prepared via a simultaneous carbonization and activation process. The adsorption properties of the prepared samples were evaluated by removing methylene blue from waste water. The factors that affect the adsorption process were examined, including initial concentration, contact time and pH of methylene blue solution. The resulting that BSNC-800-4 performed better in methylene blue removal from waste water, due to its high specific surface area (2270.9 m² g⁻¹), proper pore size (2.19 nm) and relatively high nitrogen content (1.06%). Its equilibrium data were well fitted to Langmuir isotherm model with a maximum monolayer adsorption capacity of 458 mg g⁻¹ and a removal efficiency of 91.7% at methylene blue concentration of 500 mg L⁻¹. The pseudo-second-order kinetic model could be used to accurately estimate the carbon material’s (BSNC-800-4) adsorption process. The adsorption mechanism between methylene blue solution and BSNC-800-4 was controlled by film diffusion. This study provides an alternative way to develop nitrogen self-doped activated carbons to better meet the needs of the adsorption applications.

Investigating pyrolysis characteristics of moso bamboo through TG-FTIR and Py-GC/MS

This study was carried out to investigate pyrolysis characteristics of moso bamboo (Phyllostachys pubescens), including outer layer (OB), middle layer (MB) and inner layer (IB) and bamboo leaves (BL), through TG-FTIR and Py-GC/MS. The results showed that 70% of weight loss occurred at rapid pyrolysis stage with temperature of 200-400 °C. With increase in heating rate, pyrolysis process shifted toward higher temperature. IB, OB, MB and BL had a different activation energy at different conversion rates. BL had a higher activation energy than IB, OB and MB. The volatiles of bamboo was complicated with 2-30 of C atoms. IB, OB and MB mainly released benzofuran, hydroxyacetaldehyde and 2-Pentanone. BL released furan, acetic acid and phenol. The main pyrolysis products included H₂O, CH₄, CO₂, CO, carboxylic acids, NO, NO₂. Pyrolysis products of IB was the most and that of BL was the lowest. MB had the lowest pyrolysis temperature.

Investigating co-combustion characteristics of bamboo and wood

To investigate co-combustion characteristics of bamboo and wood, moso bamboo and masson pine were torrefied and mixed with different blend ratios. The combustion process was examined by thermogravimetric analyzer (TGA). The results showed the combustion process of samples included volatile emission and oxidation combustion as well as char combustion. The main mass loss of biomass blends occurred at volatile emission and oxidation combustion stage, while that of torrefied biomass occurred at char combustion stage. With the increase of bamboo content, characteristic temperatures decreased. Compared with untreated biomass, torrefied biomass had a higher initial and burnout temperature. With the increase of heating rates, combustion process of samples shifted to higher temperatures. Compared with non-isothermal models, activation energy obtained from isothermal model was lower. The result is helpful to promote development of co-combustion of bamboo and masson pine wastes.

Antimicrobial Bamboo Materials Functionalized with ZnO and Graphene Oxide Nanocomposites

Bamboo materials with improved antibacterial performance based on ZnO and graphene oxide (GO) were fabricated by vacuum impregnation and hydrothermal strategies. The Zn2+ ions and GO nanosheets were firstly infiltrated into the bamboo structure, followed by dehydration and crystallization upon hydrothermal treatment, leading to the formation of ZnO/GO nanocomposites anchored in the bulk bamboo. The bamboo composites were characterized by several techniques including scanning electron microscopy (SEM), Fourier transform infrared spectra (FTIR), and X-ray diffraction (XRD), which confirmed the existence of GO and ZnO in the composites. Antibacterial performances of bamboo samples were evaluated by the bacteriostatic circle method. The introduction of ZnO/GO nanocomposites into bamboo yielded ZnO/GO/bamboo materials which exhibited significant antibacterial activity against Escherichia coli (E. coli, Gram-negative) and Bacillus subtilis (B. subtilis, Gram-positive) bacteria and high thermal stability. The antimicrobial bamboo would be expected to be a promising material for the application in the furniture, decoration, and construction industry.

Investigating pyrolysis and combustion characteristics of torrefied bamboo, torrefied wood and their blends

Bamboo and masson pine was torrefied with 300°C of temperature for 2.0h of residence time using GSL 1600X tube furnace in the argon atmosphere. Torrefied bamboo and masson pine particles were uniform mixed with different weight ratios. Pyrolysis and combustion characteristics were investigated through thermogravimetry (TGA). The results showed that pyrolysis and combustion process of all samples included three steps even though their characteristics were different. Torrefied biomass had a higher pyrolysis and combustion temperature, due to moisture and volatile removal and thermal decomposition of hemicelluloses, cellulose and lignin during torrefaction process. Torrefaction also increased high heating value, ash content and C/H and C/O ratio of biomass. The synergy of torrefied bamboo and torrefied mason pine was not found during pyrolysis and combustion process of blends. The results from this research will be very important and helpful to develop and utilize the wastes of masson pine and bamboo for energy products.

Fouling and long-term durability of an integrated forward osmosis and membrane distillation system

An integrated forward osmosis (FO) and membrane distillation (MD) system has great potential for sustainable wastewater reuse. However, the fouling and long-term durability of the system remains largely unknown. This study investigates the fouling behaviour and efficiency of cleaning procedures of FO and MD membranes used for treating domestic wastewater. Results showed that a significant decline in flux of both FO and MD membranes were observed during treatment of wastewater with organic foulants. However, shear force generated by the increased cross-flow physically removed the loosely attached foulants from the FO membrane surface and resulted in 86-88% recovery of flux by cleaning with tap water. For the MD membrane, almost no flux recovery was achieved due to adsorption of organic foulants on the hydrophobic membrane surface, thus indicating significant irreversible fouling/wetting, which may not be effectively cleaned even with chemical reagents. Long-term (10 d) tests showed consistent performance of the FO membrane by rejecting the contaminants. However, organic foulants reduced the hydrophobicity of the MD membrane, caused wetting problems and allowed contaminants to pass through. The results demonstrate that combination of the FO and MD processes can effectively reduce irreversible membrane fouling and solve the wetting problem of the MD membrane.

A Nozaki-Hiyama-Kishi Ni(II)/Cr(II) coupling approach to the phomactins

[reaction: see text] Through a unified synthetic strategy, appropriately functionalized bicyclic starting materials can be elaborated via Ni(II)/Cr(II) macrocylization to [9.3.1] bicycles. Elaboration of these core structures allows access to phomactin C/D analogues and establishes the first synthetic approach to phomactin A affording an intact octahydrochromene/macrocyclic ring system.