Evidences suggest that tumor microenvironment may play an important role in cancer drug resistance. Sphingosine kinase 2 (SphK2) is proposed to be the key regulator of sphingolipid signaling. This study is aimed to investigate whether the combination of molecular targeting therapy using a specific inhibitor of SphK2 (ABC294640), with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can enhance the apoptosis of non-small cell lung cancer (NSCLC) cells. Our results revealed that NSCLC cells' sensitivity to TRAIL is correlated with the level of SphK2. Compared with TRAIL alone, the combination therapy enhanced the apoptosis induced by TRAIL, and knockdown of SphK2 by siRNA presented a similar effect. Combination therapy with ABC294640 increased the activity of caspase-3/8 and up-regulated the expression of death receptors (DR). Additional investigations revealed that translocation of DR4/5 to the cell membrane surface was promoted by adding ABC294640. However, expression of anti-apoptosis proteins such as Bcl(-)2 and IAPs was not significantly modified by this SphK2 inhibitor. Overall, this work demonstrates that SphK2 may contribute to the apoptosis resistance in NSCLC, thus indicating a new therapeutic target for resistant NSCLC cells.

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Biomass plays a crucial role in mitigating the concerns associated with increasing fossil fuel combustion. Among various types of biomass, forest biomass has attracted considerable attention given its abundance and variations. In this work, an overview is presented on different pathways available to convert forest biomass into bioenergy. Direct use of forest biomass could reduce carbon dioxide emissions associated with conventional energy production systems. However, there are certain drawbacks to the direct use of forest biomass, such as low energy conversion rate and soot emissions and residues. Also, lack of continuous access to biomass is a severe concern in the long-term sustainability of direct electricity generation by forest biomass. To solve this problem, co-combustion with coal, as well as pelletizing of biomass, are recommended. The co-combustion of forest biomass and coal could reduce carbon monoxide, nitrogen oxides, and sulfide emissions of the process. Forest biomass can also be converted into various liquid and gaseous biofuels through biochemical and thermochemical processes, which are reviewed and discussed herein. Despite the favorable features of forest biomass conversion processes to bioenergy, their long-term sustainability should be more extensively scrutinized by future studies using advanced sustainability assessment tools such as life cycle assessment, exergy, etc.

Aqueous polyurethane dispersion (PUD) has attracted increasing attention in a wide range of industrial applications because of their versatile properties as well as ecofriendly nature. In this study, the aqueous PUD used in warp-knitted vamp printing was characterized by Fourier transform infrared spectra, dynamic light scattering, and laser Doppler electrophoresis. The mean diameter and zeta potential are 206.6 nm and −18.3 mV, respectively. The rheological behavior of aqueous PUD as a function of shear rate, temperature, and solid content was investigated experimentally. Besides, a new correlation model was proposed based on the Carreau equation and Arrhenius relation. The resulting model has high accuracy in viscosity estimation under complex conditions according to the prediction interval of 95%. Furthermore, the reasonable ranges of parameters were proposed theoretically for successful printing.

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