[Expression of Tregs and IL-35 in Peripheral Blood of Patients with Newly Diagnosed Acute Myeloid Leukemia].

OBJECTIVE: To explore the expression of regulatory T cells (Tregs) and interleukin-35 (IL-35) in peripheral blood of patients with newly diagnosed acute myeloid leukemia (AML). METHODS: Peripheral blood samples were collected from 33 newly diagnosed AML patients and 40 healthy volunteers. The levels of innate and adaptive immune cells and Tregs were detected by flow cytometry. Plasma IL-35 level was detected by enzyme-linked immunosorbent assay (ELISA). The expression levels of P35 and EBI3 mRNA were detected by RT-PCR. The correlation between the levels of Tregs and IL-35 was analyzed. RESULTS: The proportion of CD4+T cells, CD8+T cells, B cells and NK cells in peripheral blood of newly diagnosed AML patients were significantly lower than those of control group (P<0.05). The levels of Tregs, IL-35, and the expression of P35 mRNA and EBI3 mRNA were significantly higher than that of healthy control group (P<0.01). The Tregs level was positively correlated with plasma IL-35 level (r=0.668,P<0.01). CONCLUSION: AML patients have a deficiency in immune function, which is characterized by the high levels of Tregs and IL-35 in peripheral blood, and it might be a new target for the treatment of AML.

Metatranscriptomic evidence for classical and RuBisCO-mediated CO2 reduction to methane facilitated by direct interspecies electron transfer in a methanogenic system.

In a staged anaerobic fluidized-bed ceramic membrane bioreactor, metagenomic and metatranscriptomic analyses were performed to decipher the microbial interactions on the granular activated carbon. Metagenome bins, representing the predominating microbes in the bioreactor: syntrophic propionate-oxidizing bacteria (SPOB), acetoclastic Methanothrix concilii, and exoelectrogenic Geobacter lovleyi, were successfully recovered for the reconstruction and analysis of metabolic pathways involved in the transformation of fatty acids to methane. In particular, SPOB degraded propionate into acetate, which was further converted into methane and CO2 by M. concilii via the acetoclastic methanogenesis. Concurrently, G. lovleyi oxidized acetate into CO2, releasing electrons into the extracellular environment. By accepting these electrons through direct interspecies electron transfer (DIET), M. concilii was capable of performing CO2 reduction for further methane formation. Most notably, an alternative RuBisCO-mediated CO2 reduction (the reductive hexulose-phosphate (RHP) pathway) is transcriptionally-active in M. concilii. This RHP pathway enables M. concilii dominance and energy gain by carbon fixation and methanogenesis, respectively via a methyl-H4MPT intermediate, constituting the third methanogenesis route. The complete acetate reduction (2 mole methane formation/1 mole acetate consumption), coupling of acetoclastic methanogenesis and two CO2 reduction pathways, are thermodynamically favorable even under very low substrate condition (down to to 10-5 M level). Such tight interactions via both mediated and direct interspecies electron transfer (MIET and DIET), induced by the conductive GAC promote the overall efficiency of bioenergy processes.

Shaping microbial consortia in coupling glycerol fermentation and carboxylate chain elongation for Co-production of 1,3-propanediol and caproate: Pathways and mechanisms.

Glycerol is presently being generated in surplus with the rapid growth of the biodiesel industry and seeks ways to be upcycled, rather than to be treated with costs. Glycerol for the co-production of 1,3-propanediol (1,3-PDO) and caproate has a great prospect. Yet, its technical difficulty lies in the enhancement of caproate productivity, which requires the presence of ethanol as a co-substrate and necessitates the co-existence of functional microbes for glycerol fermentation and chain elongation. This study successfully achieved 6.38 mM C 1,3-PDO d-1 and 2.95 mM C caproate d-1 in a 2-L mixed-cultured semi-continuous fermenter with a glycerol-ethanol-acetate stoichiometric ratio of 4:3:1. Such conversions were mainly facilitated by a microbial community of Eubacterium limosum, Clostridium kluyveri and Massilibacterium senegalense. With such a synergistic microbiome, the co-production of 1,3-PDO and caproate was achieved from glycerol without ethanol addition. Based on metagenomics, E. limosum is capable of converting glycerol to 1,3-PDO, ethanol and H2, and also redirecting the electron potential of H2 into acetate via the Wood-Ljungdahl pathway, which is then used for chain elongation. C. kluyveri worked synergistically with E. limosum by consuming ethanol and acetate for caproate production. M. senegalense encodes for ethanol oxidation to acetate and butyrate, facilitating the generation of these intermediates for C. kluyveri elongation to caproate. During the transition between fermentation and elongation, an unexpected observation of poly-ß-hydroxybutyrate (PHB) formation and reutilization by M. senegalense may be associated with butyrate formation for further caproate generation. The knowledge gleaned from the substrate constitute, microbial consortium and their synergetic metabolism demonstrates a resource upgrade potential for crude glycerol or glycerol-containing wastewater generated from the biodiesel industry.

A review on the bioenergetics of anaerobic microbial metabolism close to the thermodynamic limits and its implications for digestion applications.

The exploration of the energetics of anaerobic digestion systems can reveal how microorganisms cooperate efficiently for cell growth and methane production, especially under low-substrate conditions. The establishment of a thermodynamically interdependent partnership, called anaerobic syntrophy, allows unfavorable reactions to proceed. Interspecies electron transfer and the concentrations of electron carriers are crucial for maintaining this mutualistic activity. This critical review summarizes the functional microorganisms and syntroph partners, particularly in the metabolic pathways and energy conservation of syntrophs. The kinetics and thermodynamics of propionate degradation to methane, reversibility of the acetate oxidation process, and estimation of microbial growth are summarized. The various routes of interspecies electron transfer, reverse electron transfer, and Poly-ß-hydroxyalkanoate formation in the syntrophic community are also reviewed. Finally, promising and critical directions of future research are proposed. Fundamental insight in the activities and interactions involved in AD systems could serve as a guidance for engineered systems optimization and upgrade.

Aminosilane-Assisted Electrodeposition of Gold Nanodendrites and Their Catalytic Properties.

A promising alternative route for the synthesis of three-dimensional Au dendrites was developed by direct electrodeposition from a solution of HAuCl4 containing 3-aminopropyltriethoxysilane (APTS). Ultraviolet-visible spectroscopy, fourier transform infrared spectroscopy and isothermal titration calorimetry were used to study the interaction of APTS in electrolyte. The effect of APTS on the formation of the hierarchical structure of Au dendrites was investigated by cyclic voltammetry, rotating disk electrode, electrochemical impedance spectroscopy and quartz crystal microbalance. The growth directions of the trunks and branches of the Au dendrites can be controlled by sweep-potential electrodeposition to obtain more regular structures. The efficacy of as-synthesised Au dendrites was demonstrated in the enhanced electro-catalytic activity to methanol electro-oxidation and the high sensitivity of glucose detection, which have potential applications in direct-methanol fuel cells and non-enzymatic electrochemical glucose biosensors, respectively.

Thermodynamic and physiological study of caproate and 1,3-propanediol co-production through glycerol fermentation and fatty acids chain elongation.

An alternative process for anaerobic wastewater treatment with methane recovery is to elongate the carbon chain of volatile fatty acids (VFAs) with a formation of medium chain carboxylic acids (MCCAs), e.g. n-caproic acid with higher monetary value. A potential electron donor is glycerol as a surplus byproduct from the rapid growth of waste-derived biodiesel industry. In the current approach, an industrial chemical, 1,3-propanediol (1,3-PDO) is produced from crude glycerol along with a formation of other soluble byproducts including ethanol and volatile fatty acids (VFAs), which necessitates a significant amount of energy input for separation and purification. To circumvent the energy sink requirement and upcycle both the wastewater treatment process and the biodiesel industry, it is highly beneficial to produce a valuable secondary product from the byproducts. This pioneer study reports on thermodynamic and physiological insights gained into the co-production of 1,3-PDO and caproate from glycerol. Thermodynamics analysis demonstrated that a higher pH range is more favorable when either glycerol or ethanol acting as an electron donor, whereas a high partial pressure (27% at 1 atm) and a low pH (≤5.5) are advantageous for caproate formation with hydrogen. With the glycerol-to-acetate molar ratio of 4 and pH of 7, the physiological experiments achieved a co-production of 1,3-PDO and caproate. However, the caproate yield was low and found to be kinetic-limited. Caproate formation was significantly increased by the intermediate ethanol addition with the optimal mono-caproate formation obtained at the ethanol-to-acetate molar ratio of 3. A synergistic relationship was evinced through microbial characterization, resulting in Clostridium kluyveri and some bacteria with function of converting glycerol to VFAs. This study demonstrates that sufficient ethanol produced as an intermediate is capable of enhancing caproate formation in a synergistic pathway along with 1,3-PDO. The knowledge gleaned paves new avenues for the biodiesel industry by upcycling the byproduct crude glycerol into 1,3-PDO and caproate.