This study investigates the leaching kinetics of gold-bearing pyrite in the potassium peroxydisulphate system and the potassium peroxydisulphate-ferrous sulphate combined system, using potassium peroxydisulphate as an oxidizing agent. Experimental results indicate that the pyrite leaching rate is roughly proportional to the potassium sulphate concentration. The pyrite leaching rate also increases with temperature, and is 48.19% faster at 70°C than at 30°C. Additionally, the pyrite leaching rate is inversely proportional to the particle size; the leaching rate of < 0.038 mm particles is 44.31% greater than that of 0.180-0.120 mm particles. At 70°C, the concentration of ferrous sulphate has no effect. However, at the more typical leaching temperature of 30°C, the addition of ferrous sulphate and hydrogen peroxide can increase the rate of leaching. Therefore, the kinetics of pyrite leaching in the potassium peroxydisulphate system at 70°C and in the potassium peroxydisulphate-ferrous sulphate combined system at normal temperatures were investigated in detail. Pyrite leaching kinetics follows the formula kt = 1 - 2/3x - (1 - x)²'³ where solid film diffusion is the limiting process. The effective activation energy of pyrite leaching in the temperature range 30-70°C was 65.30 kJ/mol. Pyrite had a regular crystal habit prior to leaching, but exhibited faviform holes after leaching. These results provide a basis for effective leaching of gold from gold-bearing pyrite ores using the advanced oxidative leaching system.

Cardiomyocyte apoptosis plays key roles in the pathogenesis of heart diseases such as myocardial infarction. MicroRNAs are important regulators of gene expression, which are also involved in the regulation of cardiomyocyte apoptosis. However, cardiomyocyte apoptosis regulated by microRNA (miR)-122 is largely unexplored. The aim of this study focused on the role of miR-122 in cardiomyocyte apoptosis. Cardiomyocytes were isolated from neonatal mice and primarily cultured. MiR-122 mimic and inhibitor were transfected to cardiomyocytes and verified by qRT-PCR. Cell viability and apoptosis post-transfection were assessed by MTT assay and flow cytometry, respectively. Changes in expression of caspase-8 were quantified by qRT-PCR and western blot. Results showed that miR-122 mimic and inhibitor successfully induced changes in miR-122 levels in cultured cardiomyocytes (P<0.01). MiR-122 overexpression suppressed viability and promoted apoptosis of cardiomyocytes (P<0.05), and miR-122 knockdown promoted cell viability and inhibited apoptosis (P<0.05). The mRNA and protein levels of caspase-8 were elevated by miR-122 overexpression (P<0.01) and reduced by miR-122 knockdown (P<0.001). These results suggest an inductive role of miR-122 in cardiomyocyte apoptosis, which may be related to its regulation on caspase-8.

We aimed to investigate the potential role and mechanism of microRNA-30c (miR-30c) in the pathological development of chronic hepatitis B (CHB). The serum levels of miR-30c in hepatitis B virus (HBV) carrier Xinjiang Uygur patients with inactive, low-replicative, high-replicative and HBe antigen-positive CHB were investigated. HepG2 cells were co-transfected with pHBV1.3 and miR-30c mimic or inhibitor or scramble RNA. The effects of miR-30c dysregulation on HBV replication and gene expression, cell proliferation and cell cycle were then investigated. miR-30c was down-regulated in Xinjiang Uygur patients with CHB compared to healthy controls and its expression level discriminated HBV carrier patients with inactive, low-replicative, high-replicative and HBe antigen-positive risk for disease progression. Overexpression of miR-30c significantly inhibited HBV replication and the expressions of HBV pgRNA, capsid-associated virus DNA and Hbx in hepatoma cells. Moreover, overexpression of miR-30c significantly inhibited cell proliferation and delayed G1/S phase transition in hepatoma cells. Opposite effects were obtained after suppression of miR-30c. Our results indicate that miR-30c was down-regulated in Xinjiang Uygur patients with CHB, and miR-30c levels could serve as a marker for risk stratification of HBV infection. Down-regulation of miR-30c may result in the progression of CHB via promoting HBV replication and cell proliferation.

The present study screened potential genes related to lung adenocarcinoma, with the aim of further understanding disease pathogenesis. The GSE2514 dataset including 20 lung adenocarcinoma and 19 adjacent normal tissue samples from 10 patients with lung adenocarcinoma aged 45-73 years was downloaded from Gene Expression Omnibus. Differentially expressed genes (DEGs) between the two groups were screened using the t-test. Potential gene functions were predicted using functional and pathway enrichment analysis, and protein-protein interaction (PPI) networks obtained from the STRING database were constructed with Cytoscape. Module analysis of PPI networks was performed through MCODE in Cytoscape. In total, 535 upregulated and 465 downregulated DEGs were identified. These included ATP5D, UQCRC2, UQCR11 and genes encoding nicotinamide adenine dinucleotide (NADH), which are mainly associated with mitochondrial ATP synthesis coupled electron transport, and which were enriched in the oxidative phosphorylation pathway. Other DEGs were associated with DNA replication (PRIM1, MCM3, and RNASEH2A), cell surface receptor-linked signal transduction and the enzyme-linked receptor protein signaling pathway (MAPK1, STAT3, RAF1, and JAK1), and regulation of the cytoskeleton and phosphatidylinositol signaling system (PIP5K1B, PIP5K1C, and PIP4K2B). Our findings suggest that DEGs encoding subunits of NADH, PRIM1, MCM3, MAPK1, STAT3, RAF1, and JAK1 might be associated with the development of lung adenocarcinoma.

Propofol is one of the most commonly used intravenous anesthetic agents during cancer resection surgery. A previous study has found that propofol can inhibit invasion and induce apoptosis of ovarian cancer cells. However, the underlying mechanisms are not known. miR-9 has been reported to be little expressed in ovarian cancer cells, which has been related to a poor prognosis in patients with ovarian cancer. Studies have also demonstrated that propofol could induce microRNAs expression and suppress NF-κB activation in some situations. In the present study, we assessed whether propofol inhibits invasion and induces apoptosis of ovarian cancer cells by miR-9/NF-κB signaling. Ovarian cancer ES-2 cells were transfected with anti-miR-9 or p65 cDNA or p65 siRNA for 24 h, after which the cells were treated with different concentrations of propofol (1, 5, and 10 μg/mL) for 24 h. Cell growth and apoptosis were detected using MTT assay and flow cytometry analysis. Cell migration and invasion were detected using Transwell and Wound-healing assay. Western blot and electrophoretic mobility shift assay were used to detect different protein expression and NF-κB activity. Propofol inhibited cell growth and invasion, and induced cell apoptosis in a dose-dependent manner, which was accompanied by miR-9 activation and NF-κB inactivation. Knockdown of miR-9 abrogated propofol-induced NF-κB activation and MMP-9 expression, reversed propofol-induced cell death and invasion of ES-2 cells. Knockdown of p65 inhibited NF-κB activation rescued the miR-9-induced down-regulation of MMP-9. In addition, overexpression of p65 by p65 cDNA transfection increased propofol-induced NF-κB activation and reversed propofol-induced down-regulation of MMP-9. Propofol upregulates miR-9 expression and inhibits NF-κB activation and its downstream MMP-9 expression, leading to the inhibition of cell growth and invasion of ES-2 cells.

A 9-year field micro-plot experiment was conducted to investigate the use efficiency, residual effect, and fate of 15N-labelled ryegrass green manure in soil-crop system, so as to offer useful information for reasonable application of green manures on meadow burozem. Results showed that high application rate (600g per plot) of 15N-labelled ryegrass green manure resulted in reduction of percent recovery (PR)15Nplant and PR15Nsoil by 25.0% and 12.8%, respectively, and elevation of percent loss (PL)15N by 31.2%, as compared with low application rate. The 15N utilization and loss could be divided into three phases, i.e., high uptake and fast loss in the first and second growth seasons, low uptake and slow loss in the following four growth seasons, and little change in the last three growth seasons. This suggested that the green manure N had a long residual effect but its loss was faster at early phase, and thus, rational application of green manure was of considerable importance to reduce its N loss while improve its N use efficiency.