The risk assessment of rockburst intensity in the highway tunnel based on the variable fuzzy sets theory.

Rockbursts have important influences on construction safety, so the risk assessment of rockburst intensity has great significance. Firstly, the depth of the rockburst, the uniaxial compressive strength, the stress concentration coefficients, the brittleness coefficients, and the elastic energy index are selected as the evaluation index. Secondly, an assessment model is developed based on the fuzzy variable theory. And the model is proposed to assess the rockburst intensity in the highway tunnel. Finally, the results demonstrate that the results derived from the proposed model are consistent with the current specifications; the accurate rate comes to 100%. The method can determine the risk level of rockburst intensity and provide an alternative scheme. Hence, the study can accurately present a new approach to assess the rockburst intensity in the future.

A novel ent-kaurane diterpenoid analog, DN3, selectively kills human gastric cancer cells via acting directly on mitochondria.

Targeting mitochondria using proper pharmacological agents is considered an attractive strategy for cancer control and management. Herein, we report a newly synthetic triazole analog of Jaridonin, DN3, which exhibits more potent antitumor activity via acting directly on mitochondria. DN3 potently reduced viabilities of gastric cancer cell lines HGC-27 and MGC-803 through inducing apoptosis and cell cycle arrest. But, normal human gastric epithelial cell line GES-1 is more resistant to the growth inhibition by DN3 compared with gastric cancer cells. DN3 induced mitochondrial membrane potential (MMP) decrease and cytochrome c release in intact gastric cancer cell lines. Meanwhile, the DN3 treatment also caused the release of cytochrome c from mitochondria isolated from cancer cell lines in a mitochondrial permeability transition pore complex (PTPC) mediated manner, but not from mitochondria isolated from normal gastric epithelial cell. The induction of mitochondrial PTPC proteins voltage-dependent anion channel (VDAC) and cyclophilin D (CypD) were also observed in DN3-treated cells. More interestingly, DN3 mediated MMP decrease, release of cytochrome c, the expression of VDAC and CypD and apoptosis were blocked by the pretreatment of VDAC1 inhibitor (4, 4'-diisothiocyanatostilbene-2,2'-disulfonic acid, DIDS) and CypD inhibitor (cyclosporine A, CsA). In a mouse xenograft model of human gastric cancer, the treatment of 5 mg/kg DN3 led to significant tumor regression without affecting body weight. In conclusion, our findings indicate that DN3 is a potential agent for the treatment of gastric cancer through acting directly on mitochondria, and would be useful for us to design more and better anti-cancer compounds.

Clinical application and importance of one-step human CYP2C19 genotype detection.

BACKGROUND: To directly achieve cytochrome P450 2C19 gene ( CYP2C19) classification using one-step real-time fluorescent PCR detection and to verify the capabilities of this method with nucleic acid extracted from whole blood samples. METHODS: A human CYP2C19 genotyping kit based on one-step real-time fluorescent PCR detection was used to analyze whole blood or genomic DNA samples. This method was compared with pyrosequencing and another quantitative (q)PCR kit for its accuracy, repeatability, detection range analysis, sensitivity, specificity, and anti-interference analysis. RESULTS: The one-step real-time PCR method achieved a 100% accuracy rate compared with pyrosequencing and the other qPCR kit. When detecting different concentrations of known genes, concentrations of each sample ranging from 0.2 to 125 ng/µL could be correctly detected. The genotypes of samples treated with anticoagulants, including EDTA and sodium citrate, and chyle blood samples could be correctly detected. CONCLUSION: The one-step detection method demonstrated high accuracy and a wide detection range. It also had high levels of repeatability, sensitivity, and specificity for the assessment of genomic DNA test samples.

[Effect of methamphetamine exposure on S-nitrosylation of protein disulphide isomerase in PC12 cells].

OBJECTIVE: To study the effect of methamphetamine (METH) exposure on S-nitrosylation of protein disulphide isomerase and the neurotoxicity of METH in PC12 cells. METHODS: PC12 cells were exposed to different concentrations of METH, and the cell viability was assessed using the cell-counting kit-8. PC12 cells exposed to METH in the presence of the NOS inhibitor N-nitro-L-arginine (L-NNA) were examined for cell viability and S-nitrosylation of protein disulphide isomerase using the biotin-switch method, and the changes in cell morphology were examined with HE staining. RESULTS: METH exposure obviously decreased the cell viability and increased S-nitrosylation of protein disulphide isomerase, and the effect of METH was obviously inhibited by L-NNA treatment. CONCLUSION: METH can cause obvious neurotoxicity and promote S-nitrosylation of protein disulphide isomerase in PC12 cells.

S-Nitrosylating protein disulphide isomerase mediates α-synuclein aggregation caused by methamphetamine exposure in PC12 cells.

Methamphetamine (METH) belongs to Amphetamine-type stimulants, METH abusers are at high risk of neurodegenerative disorders, including Parkinson's disease (PD). However, there are still no effective treatments to METH-induced neurodegeneration because its mechanism remains unknown. In order to investigate METH's neurotoxic mechanism, we established an in vitro PD pathology model by exposing PC12 cells to METH. We found the expression of nitric oxide synthase (NOS), nitric oxide (NO) and α-synuclein (α-syn) was significantly increased after METH treatment for 24h, in addition, the aggregattion of α-syn and the S-nitrosylation of protein disulphideisomerase(PDI) were also obviously enhanced. When we exposed PC12 cells to the NOS inhibitor N-nitro-L-arginine(L-NNA) with METH together, the L-NNA obviously inhibited these changes induced by METH. While when we exposed PC12 cells to the precursor of NO L-Arginine together with METH, the L-Arginine resulted in the opposite effect compared to L-NNA. And when we knocked down the PDI gene, the L-NNA did not have this effect. Therefore, PDI plays a significant role in neurological disorders related to α-syn aggregation, and it suggests that PDI could be as a potential target to prevent METH-induced neurodegeneration.