Genetic analysis of ORF5 porcine reproductive and respiratory syndrome virus isolated in Vietnam

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most economically important swine pathogens because it is highly infectious and causes economic losses due to decreased pig productivity. In this study, the 603 bp complete major envelope protein encoding gene (ORF5) of 32 field PRRSV isolates from Vietnam collected during 2008–2012 were sequenced and analyzed. Multiple nucleotide (nt) and deduced amino acid (aa) alignments of ORF5 were performed on the 32 isolates: the representative strains (European and North American genotypes), Chinese strains available in GenBank and vaccine strains licensed for use in Vietnam. The results showed 94.8–100.0% nt identity and 94.0–100% aa similarity among the 32 isolates. These isolates shared similarities with the prototype of the North American PRRSV strain (VR‐2332; nt 87.8–89.3%, aa 87.5–90.0%), and Lelystat virus, the prototype of the European PRRSV strain (LV; nt 61.1–61.9%, aa 55.1‐57.0%). There was greater similarity with QN07 (nt 96.5‐98.5%, aa 96.0‐99.0%) from the 2007 PRRS outbreak in QuangNam Province, CH‐1a (nt 93.2–95.1%, 91.5–93.5%) isolated in China in 1995 and JXA1 (nt 96.5–98.6%, aa 95.0–98.0%), the highly pathogenic strain from China isolated in 2006. The Vietnamese isolates were more similar to JXA1‐R (nt 96.5–98.6%, aa 95.0–98.0%), the strain used in Chinese vaccines, than to Ingelvac MLV/BSL‐PS (nt 87.2–89.0%, aa 86.0–89.0%). Phylogenetic analysis showed that the 32 isolates were of the North American genotype and classified into sub‐lineage 8.7. This sub‐lineage contains highly pathogenic Chinese PRRSV strains. This study documents genetic variation in circulating PRRSV strains and could assist more effective use of PRRS vaccines in Vietnam.     

Liposomal Delivery Systems for Encapsulation of Ferrous Sulfate: Preparation and Characterization

Liposomal delivery systems for water-soluble bioactives were prepared using the pro-liposome and the microfluidization technologies. Iron, an essential micronutrient as ferrous sulfate and ascorbic acid, as an antioxidant for iron were encapsulated in the liposomes. Liposomes prepared by the microfluidization technology using 6% (w/w) concentration of the lipid encapsulated with ferrous sulfate and ascorbic acid had particle size distributions around 150 to 200 nm, whereas liposomes from the pro-liposome technology resulted in particle sizes of about 5 μm. The encapsulation efficiency of ferrous sulfate was 58% for the liposomes prepared by the microfluidization using 6% (w/w) lipid and 7.5% of ferrous sulfate concentrations, and it was 11% for the liposomes from pro-liposome technology using 1.5% (w/v) lipid and 15% of ferrous-sulfate concentration. Both the liposomes exhibited similar levels of oxidative stability, demonstrating the feasibility of microfluidization-based liposomal delivery systems for large-scale food/nutraceutical applications.     

3 Origins and evolution of the translation machinery

The protein synthesis machinery largely evolved prior to the last common ancestor and hence its study can provide insight to early events in the origin of life, including the transition from the hypothetical RNA world to living systems as we know them. By utilizing information from primary sequences, atomic resolution structures, and functional properties of the various components, it is possible to identify timing relationships (Hsiao et al., 2009; Fox, 2010). Taken together, these timing events are used to develop a preliminary time line for major evolutionary events leading to the modern protein synthesis machinery. It has been argued that a key initial event was the hybridization of two or more RNAs that created the peptidyl transferase center, (PTC), of the ribosome (Agmon et al. 2005). The PTC, left side of figure, contains a characteristic cavity/pore that serves as the entrance to the exit tunnel and is thought to be essential to the catalysis (Fox et al., 2012). This cavity is distinct from typical RNA pores (right side of figure) in that the nitrogenous bases face towards the lumen of the pore and thus are available for hydrogen bonding interactions. In typical RNA pores, the bases carefully avoid the lumen region. In support of Agmon et al. 2005), it is argued that this key difference reflects the fact the pore was created by an early hybridization event rather than normal RNA folding.     

Revisiting the Asian second-generation advantage

Asian Americans comprise 6.4% of the US population, but account for over 20% of the country’s elite Ivy League students. While researchers have studied mechanisms that promote an “Asian second-generation advantage” in education, including immigrant hyper-selectivity, few have examined whether this advantage extends into the labour market. Focusing on the five largest Asian groups – Chinese, Indians, Filipinos, Vietnamese, and Koreans – we revisit the thesis of Asian second-generation advantage. We argue that how we define advantage – as outcomes or mobility, in education or in occupations – matters. Our analyses reveal that all five second-generation Asian groups attain exceptional educational outcomes, but vary in intergenerational mobility. Second-generation Vietnamese exhibit the greatest intergenerational gains, followed by second-generation Chinese and Koreans; second-generation Indians and Filipinos experience none. Moreover, this advantage disappears in the labour market for all groups, except for Chinese, revealing the domain-specific nature of the Asian second-generation advantage.     

The Src Homology 3 Domain-containing Guanine Nucleotide Exchange Factor Is Overexpressed in High-grade Gliomas and Promotes Tumor Necrosis Factor-like Weak Inducer of Apoptosis-Fibroblast Growth Factor-inducible 14-induced Cell Migration and Invasion via Tumor Necrosis Factor Receptor-associated Factor 2

Glioblastoma (GB) is the highest grade of primary adult brain tumors, characterized by a poorly defined and highly invasive cell population. Importantly, these invading cells are attributed with having a decreased sensitivity to radiation and chemotherapy. TNF-like weak inducer of apoptosis (TWEAK)-Fn14 ligand-receptor signaling is one mechanism in GB that promotes cell invasiveness and survival and is dependent upon the activity of multiple Rho GTPases, including Rac1. Here we report that Src homology 3 domain-containing guanine nucleotide exchange factor (SGEF), a RhoG-specific guanine nucleotide exchange factor, is overexpressed in GB tumors and promotes TWEAK-Fn14-mediated glioma invasion. Importantly, levels of SGEF expression in GB tumors inversely correlate with patient survival. SGEF mRNA expression is increased in GB cells at the invasive rim relative to those in the tumor core, and knockdown of SGEF expression by shRNA decreases glioma cell migration in vitro and invasion ex vivo. Furthermore, we showed that, upon TWEAK stimulation, SGEF is recruited to the Fn14 cytoplasmic tail via TRAF2. Mutation of the Fn14-TRAF domain site or depletion of TNF receptor-associated factor 2 (TRAF2) expression by siRNA oligonucleotides blocked SGEF recruitment to Fn14 and inhibited SGEF activity and subsequent GB cell migration. We also showed that knockdown of either SGEF or RhoG diminished TWEAK activation of Rac1 and subsequent lamellipodia formation. Together, these results indicate that SGEF-RhoG is an important downstream regulator of TWEAK-Fn14-driven GB cell migration and invasion.     

Cloning and Expression of Genes Encoding F107-C and K88-1NT Fimbrial Proteins of Enterotoxigenic Escherichia coli from Piglets

We cloned two genes coding F107-C and K88-1NT fimbrial subunits from strains E. coli C and 1NT isolated from Thua Thien Hue province, Vietnam. The mature peptide of faeG gene from strain E. coli 1NT (called faeG-1NT) is 100 % similarity with faeG gene, while the CDS of fedA gene from strain C (called fedA-C) has a similarity of 97 % with the fedA gene. Expression of the faeG-1NT and fedA-C genes in E. coli BL21 Star™ (DE3) produced proteins of ~31 and 22 kDa, respectively. The effect of IPTG concentration on the K88-1NT and F107-C fimbriae production was investigated. The results showed that 0.5 mM IPTG is suitable for higher expression of K88-1NT subunit, while 0.75 mM IPTG strongly stimulated expression of F107-C subunit. The optimal induction time for expression was also examined. Generally, highest expression of K88-1NT subunit occurred after 6 h of induction, while that of F107-C subunit is after 14 h.     

Partitioning of oxygen uptake and cost of surfacing during swimming in the air-breathing catfish Pangasianodon hypophthalmus

Though air-breathing has probably evolved mainly as a response to hypoxia, it may provide an important oxygen supplement when metabolism is elevated, as for example during swimming. Due to the increased travelling distance involved when an air-breathing fish swims to and from the surface, and the increased drag when the surface is breached, it can be proposed that air-breathing results in a rise in the apparent cost of transport. In order to investigate this hypothesis, it is necessary to use a fish that is able to swim equally well with and without access to air. The striped catfish Pangasianodon hypophthalmus has been shown to have a sufficiently high capacity for aquatic oxygen uptake in normoxia, to allow for such a comparison. Here, we measured the partitioning of oxygen uptake ( $ \dot{M}{\text{O}}_{2} $ ) during swimming and recovery, and calculated the apparent cost of transport with and without access to air, under normoxic conditions. Aerial $ \dot{M}{\text{O}}_{2} $ constituted 25–40 % of the total $ \dot{M}{\text{O}}_{2} $ during swimming and less than 15 % during recovery. The net cost of transport was 25 % lower in fish that did not air-breathe compared to fish that did, showing that the cost of surfacing can be substantial. This is the first study to measure partitioning in an air-breathing fish during swimming at velocities close to the critical swimming speed.     

Context-dependent role of ATG4B as target for autophagy inhibition in prostate cancer therapy

ATG4B belongs to the autophagin family of cysteine proteases required for autophagy, an emerging target of cancer therapy. Developing pharmacological ATG4B inhibitors is a very active area of research. However, detailed studies on the role of ATG4B during anticancer therapy are lacking. By analyzing PC-3 and C4-2 prostate cancer cells overexpressing dominant negative ATG4B^C74Ain vitro and in vivo, we show that the effects of ATG4B^C74A are cell type, treatment, and context-dependent. ATG4B^C74A expression can either amplify the effects of cytotoxic therapies or contribute to treatment resistance. Thus, the successful clinical application of ATG4B inhibitors will depend on finding predictive markers of response.     

Inhibitory effect on NO production of triterpenes from the fruiting bodies of Ganoderma lucidum

Four new lanostane triterpenes, butyl lucidenate P (1), butyl lucidenate D₂ (2), butyl lucidenate E₂ (3) and butyl lucidenate Q (4) along with 11 known compounds (5–15) were isolated from the fruiting bodies of Ganoderma lucidum. Their chemical structures were established mainly by 1D and 2D NMR techniques and mass spectrometry. Their anti-inflammatory activity was evaluated against LPS-induced NO production in macrophage RAW 264.7 cells. Compounds 1, 3, 4, 9, 10 and 15 showed inhibitory potency with IC₅₀ values of 7.4, 6.4, 4.3, 9.4, 9.2 and 4.5 μM, respectively. Compounds 1, 3 and 15 dose-dependently reduced the LPS-induced iNOS expressions. Preincubation of cell with 1, 3 and 15 significantly suppressed LPS-induced expression of COX-2 protein.