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Effects of high temperature pretreatment and inoculation of Bacillus coagulans were determined relative to the physicochemical properties and bacterial community of aerobic composting of chicken manure. Chicken manure was pretreated with high temperature for 0 h (CJ), 0.5 h (T-0.5h), 1.0 h (T-1.0h), 1.5 h (T-1.5h), and 2.0 h (T-2.0h) and then inoculated with B. coagulans. Chicken manure without high temperature pretreatment was included as control (CK). The results showed that the temperature of manure in CJ, T-0.5h, T-1.0h, T-1.5h, and T-2.0h groups was 2.2 to 8.4 °C higher than the chicken manure in CK within 1 day. On day 3, the chicken manure temperature reached a peak, which was 1.5 to 7.7 °C higher than that in the CK (56.8 °C). Both inoculation of B. coagulans and high temperature pretreatment increased the abundance and diversity of the bacterial community. The abundance of Firmicutes in T-1.5h was significantly higher than that in CJ. In the temperature decreasing period, the abundance of Bacillus in T-1.5h group was significantly higher than that in the CK and CJ. Overall, it was concluded that high temperature pretreatment and B. coagulans inoculation can accelerate the temperature elevation, increase the temperature of compost, and regulate the structure of bacterial community.

In order to evaluate the effect of biochar-based microbial agent on promoting the maturity of aerobic composting of cow dung, a composting experiment was conducted with cow dung as raw material and self-made biochar-based microbial agent for 34 days, and the changes of physical and chemical indexes and microbial communities during composting were studied with pure cow drug as blank control. The results show that after adding biochar-based microbial agents, the composting temperature could reach 53 ℃ within 1 day, and the highest composting temperature is 717 ℃, which is 46 ℃ higher than that of the control group, and the high temperature period is prolonged for 3 days. By the end of composting, the moisture content, E4/E6 and GI of treatment group and control group are 29% and 33%, 15 and 19, 1455% and 1276%, respectively. Through the correlation analysis, it is found that the correlation value of accumulated temperature, moisture content, pH value and other physiochemical indicators increases by 67%, and the correlation value with bacterial phylum level increases by 56%. Therefore, the addition of 01%(w/w) biochar-based microbial agent could accelerate the decomposition process, improve microbial diversity, accelerate the succession of microbial communities and the catabolism of materials, and promote the compost maturity process, which provides theoretical basis for the application of biochar-based microbial agents in aerobic composting.

Abstract Background Patients with acute lung injury (ALI) have increased levels of pro-inflammatory mediators, which impair endothelial progenitor cell (EPC) function. Increasing the number of EPC and alleviating EPC dysfunction induced by pro-inflammatory mediators play important roles in suppressing ALI development. Because the high density lipoprotein reverse-D-4F (Rev-D4F) improves EPC function, we hypothesized that it might repair lipopolysaccharide (LPS)-induced lung damage by improving EPC numbers and function in an LPS-induced ALI mouse model. Methods LPS was used to induce ALI in mice, and then the mice received intraperitoneal injections of Rev-D4F. Immunohistochemical staining, flow cytometry, MTT, transwell, and western blotting were used to assess the effect of Rev-D4F on repairment of lung impairment, and improvement of EPC numbers and function, as well as the signaling pathways involved. Results Rev-D4F inhibits LPS-induced pulmonary edema and decreases plasma levels of the pro-inflammatory mediators TNF-α and ET-1 in ALI mice. Rev-D4F inhibited infiltration of red and white blood cells into the interstitial space, reduced lung injury-induced inflammation, and restored injured pulmonary capillary endothelial cells. In addition, Rev-D4F increased numbers of circulating EPC, stimulated EPC differentiation, and improved EPC function impaired by LPS. Rev-D4F also acted via a PI3-kinase-dependent mechanism to restore levels of phospho-AKT, eNOS, and phospho-eNOS suppressed by LPS. Conclusions These findings indicate that Rev-D4F has an important vasculoprotective role in ALI by improving the EPC numbers and functions, and Rev-D4F reverses LPS-induced EPC dysfuncion partially through PI3K/AKT/eNOS signaling pathway.

Sphingosine-1-phosphate (S1P), a bioactive sphingolipid, is recognized as a critical regulator in physiological and pathophysiological processes of atherosclerosis (AS). However, the underlying mechanism remains unclear. As the precursor cells of endothelial cells (ECs), endothelial progenitor cells (EPCs) can prevent AS development through repairing endothelial monolayer impaired by proatherogenic factors. The present study investigated the effects of S1P on the biological features of mouse bone marrow-derived EPCs and the underlying mechanism. The results showed that S1P improved cell viability, adhesion, and nitric oxide (NO) release of EPCs in a bell-shaped manner, and migration and tube formation dose-dependently. The aforementioned beneficial effects of S1P on EPCs could be inhibited by the phosphatidylinositol 3-kinase (PI3K) inhibitor of LY294002 and nitric oxide synthase (NOS) inhibitor of N’-nitro-L-arginine-methyl ester hydrochloride (L-NAME). The inhibitor of LY294002 inhibited S1P-stimulated activation of phosphorylated protein kinase B (AKT) (p-AKT) and endothelial nitric oxide synthase (eNOS) (p-eNOS), and down-regulated the level of eNOS significantly. The results suggest that S1P improves the biological features of EPCs partially through PI3K/AKT/eNOS/NO signaling pathway.