Autophagy of hepatic stellate cell induced by Clonorchis sinensis.

BACKGROUND: Clonorchis sinensis was a food-borne zoonotic parasite in the worldwide and also an important risk factor of hepatic fibrosis. Excretory/secretion products of C. sinensis (CsESPs) are involved in parasite-host interactions and contribute to the development of hepatic damage. The aim of the present study was to investigate whether CsESPs and CsTP (adult protein) could induce autophagy of hepatic stellate cells (HSCs) and further activate HSCs so as to participate in the pathogenesis of hepatic fibrosis. METHODS AND RESULTS: The human hepatic stellate cell line LX-2 was stimulated by CsESPs and CsTP. CsESPs showed the effect on cell proliferation in methyl thiazolyl tetrazolium (MTT) assay while CsTP failed. Autophagosomes and autolysosomes were observed after the transmission mRFP-EGFP-LC3 plasmid into the LX-2 cells. CsESPs had more powerful to induce the accumulation of autophagosomes and autolysosomes to enhance autophagic flux compared with CsTP. Western-blotting analysis confirmed that the ratio of LC3-II/I in LX-2 cells was up-regulated after CsESPs treatment for 6 h, which further proved that CsESPs could induce autophagy in LX-2 cells. Meanwhile, q-PCR results showed that the mRNA levels of collagen I, collagen III and α-SMA decreased in LX-2 cells after treatment with autophagy inhibitor chloroquine, whereas they increased when combination with CsESPs. CONCLUSIONS: These results suggested that CsESPs-induced autophagy might be involved in the activation of HSCs, and consequently participate in the pathogenesis of hepatic fibrosis caused by C. sinensis infection.

Carbon-coated nickel phosphide enhances efficiently electron transfer of cadmium sulfide for photocatalytic hydrogen production.

The capacitance of a co-catalyst can be likened to a "double-edged sword". Α co-catalysts with high capacitance can store photoexcited electrons, thereby facilitating charge separation within the host catalyst. However, this property simultaneously restricts electron release. Both effects are enhanced with an increasing capacitance value, implying that excessively high capacitance can significantly hinder the photocatalytic hydrogen (H2) production reaction. Herein, we have designed a metal-organic framework (MOF) -derived carbon-coated nickel phosphide (C-Ni5P4) as the co-catalyst of cadmium sulfide (CdS). When C-Ni5P4 and CdS are closely interconnected, electrons spontaneously migrate from CdS to C-Ni5P4 under irradiation due to the higher work function (WF) of C-Ni5P4 compared to CdS. Most importantly, although the WF of C-Ni5P4 is 0.1 eV lower than that of Ni5P4, its specific capacitance (1.2 mF/cm2) is also lower than that of Ni5P4 (1.3 mF/cm2). This difference dramatically promotes electron release. Thereby exerting a strong positive effect on capacitance catalysis. Therefore, 7% C-Ni5P4/CdS exhibits exceptional cyclic stability and has a remarkably high activity level of 12283 µmol/h/g and 3.8 times as many as 3.0 %Ni5P4/CdS. This study provides a theoretical basis for the advancement of photocatalysts with high efficiency in H2 production and is expected to be applied in other fields of photocatalysis.

Molybdenum-Based Co-catalysts in Photocatalytic Hydrogen Production: Categories, Structures, and Roles.

Photocatalytic hydrogen production by using solar energy has attracted great interest around the world. The main challenges are the high costs of the photocatalysts and the low efficiency of photocatalytic hydrogen production. Co-catalysts, as crucial components of photocatalysts, are usually used to stimulate photoexcited electron transfer from the light absorber to the surface, and they also catalyze the proton-reduction reaction to form H2 in water. However, most co-catalysts used in photocatalytic hydrogen production are noble metals, which are expensive and contradict the low-costs demanded by industry. Therefore, the development of earth-abundant and cheap co-catalysts to replace noble metals is necessary for photocatalytic H2 production. This account highlights the performance and roles of molybdenum-based non-noble metal co-catalysts in photocatalytic hydrogen production. We developed a series of inexpensive and efficient molybdenum-based co-catalysts. We demonstrated that more H2 could be produced by loading Mo-based co-catalysts on CdS by using the co-precipitation method than by using traditional Pt/CdS same under the same photocatalytic conditions. The molybdenum-based co-catalysts were able to form heterojunctions, which served as bridges to facilitate the transport and separation of photogenerated charges; moreover, the molybdenum-based co-catalysts were able to accept and store photoexcited electrons owing to their large specific capacitance. The stored photoelectrons could then be released according to proton-reduction processes to form H2 . Furthermore, the molybdenum-based co-catalysts were found to have metastable state structures and multiple valence states, which provided more active sites and effectively catalyzed the production of H2 and inhibited the reverse reaction. The discovery of Mo-based co-catalysts with superior properties will provide guidance for the design of new co-catalysts.

Fast and safe synthesis of micron germanium in an ammonia atmosphere using Mo2N as catalyst.

Here, we reported a new method for fast and safe synthesis of a micron germanium (Ge) semiconductor. The Ge was successfully prepared from mixed GeO2 with a low amount of MoO3 by the NH3 reduction method at 800 °C for an ultra-short time of 10 min. XRD patterns show that the Ge has a tetragonal structure. SEM images show that the size of the Ge particles is from 5 µm to 10 µm, and so it is on the micron scale. UV-visible diffuse reflectance spectroscopy shows that the Ge has good light absorption both in the ultraviolet and visible regions. The formation of Ge mainly goes through a two-step conversion in the NH3 flow. Firstly, GeO2 is converted to Ge3N4, and then Ge3N4 is decomposed to generate Ge. The comparison experiments of MoO3 and Mo2N demonstrate that Mo2N is the catalyst for the Ge synthesis which improves the Ge3N4 decomposition. The presented fast and safe synthesis method of Ge has great potential for industrialization and the proposed Mo2N boosting the Ge3N4 decomposition has provided significant guidance for other nitride decomposition systems.

Mo2 C as Non-Noble Metal Co-Catalyst in Mo2 C/CdS Composite for Enhanced Photocatalytic H2 Evolution under Visible Light Irradiation.

Co-catalysts are a major factor to enhance photocatalytic H2 activity; they are mainly composed of expensive noble metals. Here, we reported a new non-noble-metal co-catalyst Mo2 C that efficiently improves the photocatalytic H2 evolution of CdS under visible light irradiation. Mo2 C is prepared by temperature-programmed reaction with molybdenum oxide as precursor, and the Mo2 C/CdS composite is prepared by deposition of CdS on Mo2 C. The optimum composite 2.0 % Mo2 C/CdS shows a high H2 evolution rate of 161 µmol h(-1) , which is ten times higher than that of CdS alone and 2.3 times higher than the optimum for 1.0 % Pt/CdS. Moreover, the Mo2 C/CdS is stable for 50 h. This study presents a new low-cost non-noble-metal co-catalyst as a photocatalyst to achieve highly efficient H2 evolution.

Comparison between liquid and solid acids catalysts on reducing sugars conversion from furfural residues via pretreatments.

Liquid sulphuric acid is adopted and compared with carbon-based sulfonated solid acids (coal tar-based and active carbon-based) for furfural residues conversion into reducing sugars. The optimum hydrolysis conditions of liquid acid are at 4% of sulphuric acid, 25:1 of liquid and solid ratio, 175°C of reaction temperature and 120 min of reaction time. The reducing sugar yields are reached over 60% on liquid acid via NaOH/H2O2, NaOH/microwave and NaOH/ultrasonic pretreatments, whereas only over 30% on solid acids. The TOFs (turnover number frequency) via NaOH/H2O2 pretreatments are 0.093, 0.020 and 0.023 h(-1) for liquid sulphuric acid, coal tar-based and active carbon-based solid acids catalysts, respectively. Considering the efficiency, cost and environment factors, the liquid and solid acids have their own advantages of potential commercial application values.