Genetic Diversity of the ORF5 Gene of Porcine Reproductive and Respiratory Syndrome Virus Isolates in Southwest China from 2007 to 2009

To gain insight into the molecular epidemiology and possible mechanisms of genetic variation of porcine reproductive and respiratory syndrome (PRRS) in Yunnan Province of China, the ORF5 gene of 32 PRRSV isolates from clinical samples collected from 2007 to 2009 were sequenced and analyzed. Nucleotide and amino acid analyses were carried out on 32 isolates and representative strains of the North American genotype, European genotype and two representative Chinese isolates. Results revealed that these isolates share 86.9–99.0% nucleotide and 87.5–98.0% amino acid identity with VR-2332 the prototypical North American PRRSV, 61.7–62.9% and 54.3–57.8% with Lelystad virus (LV) the representative strain of European genotype, 91.2–95.4% and 90.0–94.5% with CH-1a that was isolated in mainland China in 1996, 88.1–99.3% and 85.5–99.0% with JX-A1 the representative strain of High pathogenic PRRSV in China, and 86.2–99.8% and 85.5–100.0% between isolated strains of different years, respectively. Phylogenetic analysis revealed that all 32 PRRSV isolates belonged to the North American genotype and were further divided into two different subgenotypes. Subgenotype 1 comprised twenty two Yunnan isolates which divided into two branches. Subgenotype 2 comprised ten isolates which closely related to the RespPRRS vaccine and its parent strain VR-2332. The functional domains of GP5 such as the signal peptide, ectodomain, transmembrane regions and endodomain were identified and some motifs in GP5 with known functions, such as primary neutralizing epitope (PNE) and decoy epitope were also further analyzed. Our study shown the great genetic diversity of PRRSV in southwest China, rendering the guide for control and prevention of this disease

Photo-electric capacitive deionization enabled by solar-driven nano-ionics on the edges of plasma-made vertical graphenes

Unimpeded ion traffic in carbon materials with ionic selectivity remains a challenge in electrochemical energy storage and chemical purifications represented by capacitive deionization (CDI) of potable and industrial water. In this work, a new concept of solar nano-ionics is developed to directly feed solar energy into photocarriers and localized electric fields near the edges of graphene nanostructures that enable effective, mobility-based ion transport with high mass exchange rates and selectivity. This concept is applied to demonstrate the new approach for CDI, namely the photo-electric capacitive deionization (PECDI), enabled by the solar-enhanced ionic transport. Materialized by edge-enhanced vertical graphenes (eVG), the photocarriers are localized along the edge nano-antennas of eVG to boost the edge-localized electric fields by two orders of magnitude, as confirmed by near-field photo-induced force microscopy. The localized photo-electric fields control and restructure the nano-ionic flows leading to selective transport of ions with different mobility and dramatically enhanced kinetics, as validated by in situ electrochemical quartz crystal microbalance measurements and molecular dynamics simulations. With the photo-enhanced ionic transport kinetics, an average adsorption capacity of 33 mg g−1 at 200 mg L–1 (165 mg g−1 at 5000 mg L–1), a fast adsorption/desorption response and the impressive efficiency are achieved. This work opens a new avenue for solar-enhanced nano-ionic manipulation, which can be extended for a broad range of chemical engineering, energy, and environmental applications.</p

In vitro inhibition of porcine reproductive and respiratory syndrome virus replication by short antisense oligonucleotides with locked nucleic acid modification

Abstract Background Porcine reproductive and respiratory syndrome virus (PRRSV) causes porcine reproductive and respiratory syndrome (PRRS), which is currently insufficiently controlled. From a previous small-scale screen we identified an effective DNA-based short antisense oligonucleotide (AS-ON) targeting viral NSP9, which could inhibit PRRSV replication in both Marc-145 cells and pulmonary alveolar macrophages (PAMs). The objective of this study was to explore the strategy of incorporating locked nucleic acids (LNAs) to achieve better inhibition of PRRSV replication in vitro. Methods The effective DNA-based AS-ON (YN8) was modified with LNAs at both ends as gap-mer (LNA-YN8-A) or as mix-mer (LNA-YN8-B). Marc-145 cells or PAMs were infected with PRRSV and subsequently transfected. Results Compared with the DNA-based YN8 control, the two AS-ONs modified with LNAs were found to be significantly more effective in decreasing the cytopathic effect (CPE) induced by PRRSV and thus in maintaining cell viability. LNA modifications conferred longer lifetimes to the AS-ON in the cell culture model. Viral ORF7 levels were more significantly reduced at both RNA and protein levels as shown by quantitative PCR, western blot and indirect immunofluorescence staining. Moreover, transfection with LNA modified AS-ON reduced the PRRSV titer by 10-fold compared with the YN8 control. Conclusion Taken together, incorporation of LNA into AS-ON technology holds higher therapeutic promise for PRRS control

Analysis and comparison of amino acid mutations in ORF5 gene of 32 Chinese isolates and 9 reference strains.

<p>Dots (.) indicate the same amino acids as in VR2332 and substitutions are indicated by the amino acid letter codes. The functional domains indicated by color boxes are reported according to Zhou et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0033756#pone.0033756-Zhou1" target="_blank">[11]</a>.</p

Phylogenetic relationship of PRRSVs.

<p>A neighbor-joining tree was constructed based on sequences of the ORF5 gene of PRRSV, with bootstrap values calculated from 1,000 replicates. Subgroups are marked with different colors and the strains isolated in this study are indicated in bold.</p

Analysis of nucleotide and amino acid identity of ORF5 among 32 PRRSV isolates and with represent PRRSV isolates LV, VR-2332, RespPRRSV, Ch-1a, and highly pathogenic strain JX-A1.

<p>Analysis of nucleotide and amino acid identity of ORF5 among 32 PRRSV isolates and with represent PRRSV isolates LV, VR-2332, RespPRRSV, Ch-1a, and highly pathogenic strain JX-A1.</p

Representative PRRSV Strains used in the phylogenetic and sequence analyses.

*<p>JX-A1 is the representative strain of HP-PRRSV in China since 2006;</p>#<p>Ch-1a is the first PRRSV isolate in mainland China in 1996.</p

Factors influencing platelet isolation: a prospective multicenter study from Western China

Tumor-educated platelets (TEPs) have been widely reported to have promising application potential; nonetheless, platelet isolation from peripheral blood is an important but neglected step in TEPs research for platelet-based liquid biopsy. In this article, we discussed some common influence factors for platelet isolation. To investigate the factors involved in platelet isolation, a prospective multicenter study was conducted on healthy Han Chinese adults (18 to 79 years of age). A total of 208 individuals were included in the final statistical analysis out of the 226 healthy volunteers who were prospectively enrolled from four hospitals. The primary study metric was the platelet recovery rate (PRR). The similar pattern was observed in the four hospitals, The PRR at room temperature (23°C±2°C) was slightly higher than the PRR at cold temperature (4°C±2°C). Moreover, the PRR gradually decreased as the storage time increased. The PRR for samples within 2 hours of storage is significantly higher than for samples beyond 2 hours (p < .05). Additionally, PRR was also affected by the equipment used in different centers. This study confirmed several factors that influence platelet isolation. In our study, we indicated that platelet isolation should be performed within two hours of peripheral blood draw and held at room temperature until isolation, and that centrifuge models should be fixed during the extraction process, which will further improve the research progress of platelet-based liquid biopsy in cancer