Simple and rapid detection of swine hepatitis E virus by reverse transcription loop-mediated isothermal amplification.

Hepatitis E virus (HEV) is an enteric pathogen of humans and animals, and pigs have been considered an important reservoir of this virus. Recent evidence has indicated the cross-species transmission of hepatitis E virus (HEV) from pigs to humans, causing zoonosis, mostly via consumption of uncooked or undercooked animal meat/viscera. In this study, we have developed a one-step RT-LAMP assay for rapid detection of swine HEV. Specific primer sets targeting the ORF3 gene were designed. The sensitivity of the RT-LAMP assay was 10(1) copies/µl of RNA template, which was tenfold higher than that of RT-nPCR. The specificity of this assay was demonstrated by the lack of amplification of DNA/RNA from other swine viruses. Furthermore, a total of 41 bile samples were subjected to RT-LAMP and RT-nPCR. Eighteen positive samples were detected by RT-nPCR, while 36 positive samples were detected by RT-LAMP, indicating that the sensitivity of the RT-LAMP assay was higher than that of the conventional RT-nPCR assay. The RT-LAMP assay reported here may be used for diagnosis of swine HEV, not only in laboratories but also under field conditions.

Complete Genome Sequence of a Novel Avian-Like H3N2 Swine Influenza Virus Discovered in Southern China.

We report here the complete genomic sequence of a novel avian-like H3N2 swine influenza virus containing an H5N1 highly pathogenic avian influenza virus segment that was obtained from swine in southern China. Phylogenetic analysis indicated that this virus might originate from domestic aquatic birds. The sequence information provided herein suggests that continuing study is required to determine if this virus can be established in the swine population and pose potential threats to public health.

Genetic characterization of H1N2 influenza a virus isolated from sick pigs in Southern China in 2010.

In China H3N2 and H1N1 swine influenza viruses have been circulating for many years. In January 2010, before swine were infected with foot and mouth disease in Guangdong, some pigs have shown flu-like symptoms: cough, sneeze, runny nose and fever. We collected the nasopharyngeal swab of all sick pigs as much as possible. One subtype H1N2 influenza viruses were isolated from the pig population. The complete genome of one isolate, designated A/swine/Guangdong/1/2010(H1N2), was sequenced and compared with sequences available in GenBank. The nucleotide sequences of all eight viral RNA segments were determined, and then phylogenetic analysis was performed using the neighbor-joining method. HA, NP, M and NS were shown to be closely to swine origin. PB2 and PA were close to avian origin, but NA and PB1were close to human origin. It is a result of a multiple reassortment event. In conclusion, our finding provides further evidence about the interspecies transmission of avian influenza viruses to pigs and emphasizes the importance of reinforcing swine influenza virus (SIV) surveillance, especially before the emergence of highly pathogenic FMDs in pigs in Guangdong.

Isolation and Phylogenetic Analysis of H1N1 Swine Influenza Virus from Sick Pigs in Southern China.

Two swine influenza (SI) H1N1 virus was isolated from a pig during a severe outbreak of respiratory disease in south China. The two H1N1 influenza viruses were classical SI virus. A/swine/Guangdong/L6/09 is classical SI virus of recent years, which is of the main SI virus in China. Howere, A/swine/Guangdong/L3/09 was closet to A/swine/Iowa/1931, which was the first isolated SI virus and had demonstrated significant pathogenicity in animal models. The results of phylogenetic analysis of A/swine/Guangdong/L3/09 showed a close relationship with the 1918 pandemic virus. The results suggested that the previous SI virus appeared again. Whether, it brought a new pandemic to pigs deserves more attention.

Can the positive aromatic ring be as π-electron donor in π-halogen bond? A MP2 theoretical investigation on the unusual π-halogen bond interaction between three-membered ring (BNN)3⁺ and X1X2 (X1, X2 = F, Cl, Br).

The unusual π-halogen bond interactions are investigated between (BNN)3⁺ and X1X2 (X1, X2 = F, Cl, Br) employing MP2 at 6-311 + G(2d) and aug-cc-pVDZ levels according to the "CP (counterpoise) corrected potential energy surface (PES)" method. The order of the π-halogen bond interactions and stabilities of the complexes are obtained to be (BNN)3⁺... F2 < (BNN)3⁺... ClF < (BNN)3⁺... Cl2 < (BNN)3⁺... BrCl < (BNN)3⁺... Br2 < (BNN)3⁺ ... BrF. at MP2/aug-cc-pVDZ level. The analyses of the Mulliken charge transfer, natural bond orbital (NBO), atoms in molecules (AIM) theory and electron density shifts reveal that the nature of the π-halogen bond interaction in the complexes of ClF, BrF and BrCl might partly be charge transfer from the delocalized π-HOMO orbital of (BNN)3⁺ to X1X2. This result suggests that the positive aromatic ring (BNN)3⁺ might act as a π-electron donor to form the π-halogen bond.

[Quality assessment for Coptis chinensis with different cultivating system].

OBJECTIVE: To evaluate the quality of Coptis chinensis planted with four kinds of cultivating system. METHOD: The samples, which were planted below the artificial shading, the forest of Chinese ceder wood, Mmulbery wood, Magnolia officinal wood were chosen respectivley, UV and HPLC were used to determine of total alkaloids and berberine of samples. RESULT: There was no significant difference among four kinds of cultivating system on the contents of total alkaloids and berberine. The contents of total alkaloids and berberine were obviously higher than in the criterion of Chinese Pharmacopoeia. CONCLUSION: The roots of C. chinensis planted in the four kinds of planting system can be used as medicinal material of high quality.