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Due to the large number of sensors in some power grids and the lack of networking capability, a solution of arranging relay nodes to collect sensor information and networking relay nodes is proposed. For the networking of relay nodes, a clustering routing algorithm (LEACH-WGR-SSA) is proposed, which rotates the gateway of relay node network or the root node – Wireless gateway. Furthermore, Sparrow search algorithm is introduced to optimize the election of adjacent nodes and location information are considered for the election of Wireless gateway and cluster heads. Simulation results show that the LEACH-WGR-SSA algorithm prolongs the life cycle of the network, balances the energy consumption and effectively improves the convergence speed.

PACRG (Parkin co-regulated gene) shares a bi-directional promoter with the Parkinson’s disease-associated gene Parkin, but the physiological roles of PACRG have not yet been fully elucidated. Recombinant expression methods are indispensable for protein structural and functional studies. In this study, the coding region of PACRG was cloned to a conventional vector pQE80L, as well as two cold-shock vectors pCold II and pCold-GST, respectively. The constructs were transformed into Escherichia coli (DE3), and the target proteins were overexpressed. The results showed that the cold-shock vectors are more suitable for PACRG expression. The soluble recombinant proteins were purified with Ni2+ chelating column, glutathione S-transferase (GST) affinity chromatography and gel filtration. His6 pull down assay and LC-MS/MS were carried out for identification of PACRG-binding proteins in HEK293T cell lysates, and a total number of 74 proteins were identified as potential interaction partners of PACRG. GO (Gene ontology) enrichment analysis (FunRich) of the 74 proteins revealed multiple molecular functions and biological processes. The highest proportion of the 74 proteins functioned as transcription regulator and transcription factor activity, suggesting that PACRG may play important roles in regulation of gene transcription.

A polymerase chain reaction (PCR) assay combined with immunomagnetic separation (IMS) was established to detect a virulence plasmid harbored by the bacterium Vibrio parahaemolyticus which can cause acute hepatopancreatic necrosis disease (AHPND). The outer membrane protein OmpU, a conserved antigen among Vibrio species, was evaluated as a novel capture target for the immunomagnetic separation to capture and concentrate V. parahaemolyticus from environmental sources. A PCR assay targeting pirA- (284 bp) and pirB- (392 bp) like genes was used for screening AHPND V. parahaemolyticus. Immunomagnetic beads (IMBs), coated with anti-VpOmpU antibodies, presented high capture efficiency (> 90%) for V. parahaemolyticus within 60 min. When PCR assay was combined with IMS (IMS-PCR), the detection limit was 101 CFU/mL in pure cultures and was unaffected by the presence of 105 CFU/mL of competing microflora. When applied in artificially contaminated environmental samples, the IMS-PCR could also detect as few as 101 CFU/mL AHPND V. parahaemolyticus within 4–5 h. These results suggest that the IMS-PCR approach could be a rapid and effective method for the detection of AHPND V. parahaemolyticus in shrimp and water samples from environmental sources.

To the memory of Prof. Grigori Mints, Stanford UniversityBorn: June 7, 1939, St. Petersburg, RussiaDied: May 29, 2014, Palo Alto, California

Aims. The prognosis of colorectal cancer (CRC) remains poor. This study aimed to develop and validate DNA methylation-based signature model to predict overall survival of CRC patients. Methods. The methylation array data of CRC patients were retrieved from The Cancer Genome Atlas (TCGA) database. These patients were divided into training and validation datasets. A risk score model was established based on Kaplan-Meier and multivariate Cox regression analysis of training cohort and tested in validation cohort. Results. Among total 14,626 DNA methylation candidate markers, we found that a three-DNA methylation signature (NR1H2, SCRIB, and UACA) was significantly associated with overall survival of CRC patients. Subgroup analysis indicated that this signature could predict overall survival of CRC patients regardless of age and gender. Conclusions. We established a prognostic model consisted of 3-DNA methylation sites, which could be used as potential biomarker to evaluate the prognosis of CRC patients.

Mangrove is a complex ecosystem often affected by anthropogenic activities and receiving various antibiotics and antibiotic resistance genes (ARGs). In this study, profiles of antibiotics and ARGs of seven National Mangrove Reserves in south China were investigated. Fourteen antibiotics belonging to five categories were detected by LC-MS and twelve gene families of ARGs were evaluated by GeoChip assay. Each antibiotic category, including sulfonamides, tetracyclines, fluoroquinolones, macrolides and chloramphenicols, could be detected in all seven mangroves. In the surface sediment, the detection frequency of fourteen antibiotics was higher than 85%, except for chlorotetracycline (57%). The total antibiotic concentrations were at a high level (>250 ng/g) in the mangrove sediment of Fangchenggang (501 ng/g), Hong Kong (368 ng/g), Zhanjiang (311 ng/g) and Shenzhen (268 ng/g). High concentrations of fluoroquinolones (ciprofloxacin, norfloxacin, ofloxacin and enrofloxacin) were observed in Fangchenggang (227.7 ng/g), Beihai (85.7 ng/g), Zhanjiang (108.8 ng/g), Shenzhen (119.2 ng/g), Hongkong (126.6 ng/g) and Yunxiao (93.0 ng/g). The results suggest a widespread of antibiotic pollution in these mangroves. All ARGs families were detected in all mangroves investigated in this study. The major ARGs were multidrug resistance genes (MRGs), which accounted for more than 90% of the total ARGs abundance. These MRGs, including MATE, MFS, SMR, Mex and ATR, are families of multidrug transporters related to the transport of various antibiotics. Actinobacteria and Proteobacteria were the dominant microbial clades of the hosts for major ARGs in these mangroves. The concentration of ciprofloxacin was positively correlated with the abundance of relevant ARGs (quinolone resistance determinant). This work provides a profile of antibiotics and ARGs for further study on prevalence and proliferation of these pollutants in the mangrove ecosystems.