Determination of the complete genome sequence of infectious hematopoietic necrosis virus (IHNV) Ch20101008 and viral molecular evolution in China.

This study determined the complete genomic sequence of the infectious hematopoietic necrosis virus (IHNV) strain Ch20101008 isolated from farmed brook trout (Salvelinus fontinalis) that died from a disease caused by the virus in northeast China. The sequence was determined from 10 overlapping clones obtained through RT-PCR amplification. The whole genome length of Ch20101008 comprised 11,129 nucleotides (nt), and the overall organization was typical of that observed for all other IHNV strains. The phylogenetic analysis results of the 65 IHNV glycoprotein genes and 47 IHNV partial nucleoprotein genes presented five major genogroups (J, U, L, E and M). The J genogroup included the J Nagano and J Shizuoka subgroups. The IHNV Ch20101008 strain belonged to the J Nagano subgroup of the J genogroup and was significantly related to other Chinese IHNV strains. All Chinese IHNV isolates are monophyletic, with a recent common ancestor, except for the BjLL strain. The N, P, M, G, NV and L genes of Ch20101008 were compared with the available IHNV sequences in GenBank. The results indicated that 198 nt were substituted, 53 of which exhibited amino acid change in the Ch20101008 genome. An adenine nucleotide deletion was found at position 4959 of the 5' UTR of the L gene. In the G gene, specific nucleotides and amino acid variations of the Chinese IHNV strains were observed when compared with 23 isolates from other countries. Of the 15 nucleotide sites that changed, seven resulted in amino acid substitution. The data further demonstrated that the J genogroup IHNV was introduced to and evolved in salmon farm environments in China.

Characterization of the complete genome sequence of pike fry rhabdovirus.

The complete genome sequence of pike fry rhabdovirus (PFRV), consisting of 11,097 nucleotides, was determined. The genome contains five genes, encoding the nucleoprotein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G), and RNA-dependent RNA polymerase (L) protein in the order 3'-N-P-M-G-L-5'. 3' leader- and 5' trailer-sequences in the PFRV genome show inverse complementarity. The PFRV proteins share the highest homology to the proteins of spring viremia of carp virus (SVCV), ranging from 55.3 to 91.4%. Phylogenetic analysis of the five proteins showed that PFRV clusters with SVCV and is closely related to the mammalian vesiculoviruses, 903/87, STRV and SCRV.

Low molecular weight heparin microcapsule coated occluder for atrial-septal defects.

BACKGROUND: Whether the low molecular weight heparin microcapsule coated occluder is helpful to endothelialization in atrial-septal defect models is uncertain. This study aimed to investigate the best conditions for low molecular weight heparin coated NiTi alloy occluder and provide the evidence of the efficacy and safety of atrial-septal defect occluders in vivo. METHODS: Low molecular weight heparin microcapsules were investigated using gelatin as microcapsule material. The prepared low molecular weight heparin gelatin particles were subjected to nickel and titanium alloy occluder coating by sodium hyaluronate. A dog model of atrial septal defects was established after treatment with low molecular weight heparin microcapsule coated occluder (n = 4) and uncoated occluder (n = 4). Endotheliocytes and fibroblastic cells in occluders were observed. And the rate of endothelialization was detected. RESULTS: When the concentration of gelatin was 1%, the diameters of particles were mostly about 100 microm, and the particle size was uniform. The envelope efficiency of low molecular weight heparin microcapsule was about 80%. The endothelialization of occluder in the model was more obvious in the coated group than in the uncoated group (P < 0.0001). CONCLUSIONS: Low molecular weight heparin can be prepared into microcapsules with their particle size in nanometric grade. The antithrombotic properties are kept in the nickel and titanium alloy occluder successfully coated with sodium hyaluronate. The endothelialization after the interventional occlusion in the coated group is obvious, indicating that low molecular weight heparin is helpful to the growth of endothelial cells in the occlude and the healing after the interventional occlusion.

[Comparison of characteristics of SVCV strains isolated in China and in Europe].

In the nationwide epidemiological investigation, SVCV-741 was for the first time isolated in Beijing region, China in 2003, and designated as SVCV Asian strain. In this paper, we compared SVCV-741 (Asian strains isolated in China) with SVCV-10/3 (Europe reference strain) on their physico-chemical, biological and morphological characteristics. The results indicated that there were no distinct differences between two SVCV strains on phycico-chemical and morphological characteristics. The main existing differences were: (1) The stability of SVCV-741 to temperature in cell culture was higher than that of SVCV-10/3, which might have some evolutionary and biological implication of SVCV; (2) No SVC outbreak ever occurred caused by SVCV-741;Furthermore we found that both SVCV-741 and SVCV-10/3 grew faster and produced higher virus titer in CO cells than other cell lines. It indicated that CO cell lines might be useful tool for SVCV research.