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Cytochrome P450 enzymes (CYPs), encoded by Halloween genes, mediate the biosynthesis of molting hormone, ecdysteroids, in arthropods. In this report, the effect of heavy metal cadmium (Cd) stress on the expression of cytochrome P450 genes in the wolf spider Pardosa pseudoannulata was analyzed. The results showed the expression levels of genes encoding for Cd transporters including ABC transporters, zinc transporters, calcium channel proteins and calcium binding proteins were inhibited or induced by Cd stress. In addition, the increase in metallothionein (MT) content and glutathione peroxidase (GPX) activity and decrease in total acetylcholine esterase (AChE) activity were also detected. Apparently, these detoxification methods did not completely protect the spider from the cytotoxicity of Cd stress. Increased mortality of P. pseudoannulata was observed when they were under Cd tress. In total 569 CYP genes belonging to 62 CYP subfamilies were obtained from P. pseudoannulata RNA-seq databases. BlaxtX analysis showed that 150, 161, 11, and 40 CYP genes were similar to the genes dib, phm, sad and shd, respectively, which are thought to catalyze the biosynthesis of ecdysteroids. Gene expression analysis suggested that 25 dib encoding genes, 27 phm encoding genes, 2 sad encoding genes, and 6 shd encoding genes were differentially expressed in TS2 vs. S2 comparison (Cd-treated 2nd instar spider vs. 2nd instar spider), respectively. There were 70 dib, 70 phm and 19 shd encoding genes either upregulated or downregulated, while 3 sad encoding genes were upregulated in TS5 vs. S5 (Cd-treated 5nd instar spider vs. 5nd instar spider). Genes related to heme binding and essential for activating the CYPs were also differentially expressed. Expression levels of cuticle related genes were significant differentially expressed, implying the changes in activities of chitin synthases and chitinase. Therefore we assume that unsuccessful molting process may occur on P. pseudoannulata due to influenced ecdysteroids levels, thus increasing mortality of spider.

In this paper, a new shock model is proposed to fit the situation that the damage process of the component is accelerated with the increase of the degree of damage in shock environments. Shocks with the same magnitude may have more serious consequences as the component gets worse and component states are divided into different stages according to the degree of damage. Reliability indexes of a series system which consists of two components with the above characteristics are derived by using a Markov renewal process. Then, an opportunistic maintenance strategy is proposed for the system and an optimization model is constructed to obtain the optimal maintenance solutions. Finally, a numerical example for a two-rolling bearing system of a wind turbine is presented to illustrate the proposed shock model and maintenance strategy. Sensitivity analysis of maintenance costs is also discussed in order to improve the reliability of the proposed model. This study is of reference value and application significance for similar series systems.

The practical application of elevated carbohydrate antigen 125 (CA125) to predict clinical outcome in chronic heart failure (CHF) is under debate. The mechanism for this CA125 elevation remains unknown. We hypothesize that mechanical stress on mesothelial cells initiates CA125 synthesis.A total of 191 patients suffering from edema and/or dyspnea were enrolled. 109 patients were diagnosed as CHF, and 82 patients without CHF were assigned as control group. Echocardiography, CA125, N-terminal pro-brain natriuretic peptide (NT-proBNP), and other biochemical parameters were measured. All enrolled patients underwent heart function classification.Patients with serous cavity effusion (SCE) demonstrated higher serum CA125 than patients without SCE (82.91 (61.90-103.92) vs. 44.98 (29.66-60.30) U/mL, P0.001). In the absence of SCE, CA125 levels in CHF patients were slightly higher than non-CHF patients (52.37 (34.85-69.90) vs. 35.15 (23.81-46.49) U/mL, P=0.017). Additionally, compared with non-CHF patients, CHF patients had higher levels of high-sensitivity C-reactive protein (hsCRP) and lower superoxide dismutase (SOD). In all enrolled patients, CA125 levels were negatively correlated with SOD concentrations (r=-0.567, P0.001), and positively correlated with hsCRP levels (r=0.608, P0.001). Receiver operating characteristic curve analysis showed that CA125 was better in predicting SCE than NT-proBNP, while NT-proBNP was more suitable for predicting CHF than CA125. The in vitro study demonstrated that MUC16, the CA125 coding gene, was up-regulated by mechanical stretch on human mesothelial cell line (MeT-5A).CA125 elevation in CHF was associated with SCE. Mechanical extension of mesothelial cells from SCE plays an important role in CA125 increase.