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Flavokawains are chalcones that can be found in the root extracts of the kava-kava (Piper methysticum) plant. Flavokawain A and flavokawain B are known to possess potential anti-inflammation and anti-cancer activities. Nevertheless, the effects of both these compounds on the normal function of the host have not been studied. There is a need to find agents that can enhance the functionality of the immune system without disturbing the homeostatic balance. This study aimed to determine the toxicity and immunomodulatory effects of flavokawain A and flavokawain B on Balb/c mice. Several assays were conducted, the MTT viability assay, cytokine detection (IL-2 and TNF-), immunophenotyping of important immune markers, serum biochemical analysis and detection of nitric oxide levels. Based on our results, flavokawain A and B did not cause mortality and all mice were observed normal after the treatment period. Both flavokawains stimulated splenocyte proliferation, the secretion of IL-2 and TNF-α and raised the population of T cell subsets without significantly altering the level of several serum biochemical parameters. Overall, flavokawain A and B could serve as potential immune-modulator drugs without causing any toxicity, however further in vivo evidence is needed.

Base usage and dinucleotide frequency have been extensively studied in many eukaryotic organisms and bacteria, but not for viruses. In this paper, a comprehensive analysis of these aspects for infectious bursal disease virus (IBDV) was presented. The analysis of base usage indicated that all of the IBDV genes possess equivalent overall nucleotide distributions. However when the base usage at each codon positions was analysed by using cluster analysis, the VP5 open reading frame (ORF) formed a different cluster isolated from the other genes. The unusual base usage of VP5 ORF may indicate that the gene was originated by the virus "overprinting strategy", a strategy in which virus may create novel gene by utilizing the unused reading frames of its existing genes. Meanwhile, the GC content of the IBDV genes and the chicken's coding sequences was comparable; suggesting the virus imitation of the host to increase its translational efficiency. The analysis of dinucleotide frequency indicated that IBDV genome had dinucleotide bias: the frequencies of CpG and TpA were lower and the TpG was higher than the expected. Classical methylation pathway, a process where CpG converted to TpG, may explain the significant correlation between the CpG deficiency and TpG abundance. "Principal component analysis of the dinucleotide frequencies" (DF-PCA) was used to analyse the overall dinucleotide frequencies of IBDV genome. DF-PCA on the hypervariable region and polyprotein (VPX-VP4-VP3) gene showed that the very virulent IBDV (vvIBDV) was segregated from other strains; which meant vvIBDV had a unique dinucleotide pattern. In summary, the study of base usage and dinucleotide frequency had unravelled many overlooked genomic properties of the virus.

Background Salmonella enterica serovar Typhimurium persists as one of the most frequent food-borne zoonoses, causing a major public health concern worldwide. Furthermore, Salmonella infection has a large economic impact. Globally, the main sources of infection for humans include the consumption of contaminated poultry meat and eggs. In animals however, Salmonella transmission usually occurs horizontally from infected birds and contaminated environments. Hence, to delve further on how the impact of this disease can be lessened, an epidemiological study needs to be performed. It is vital to determine the genomic sequences of microorganisms to understand their biology and functional characterization. Thus, we determined the whole-genome sequence and virulence profile of S. enterica serovar Typhimurium strain UPM 260 isolated from Perak, Malaysia. Whole genome sequencing (WGS) using paired-end sequencing generated 107 contigs with a total genome size of 4.9 Mbp and 52% G+C content. The contigs were annotated for phylogenetic and functional analysis. Results Through the analysis, it is revealed that the genome were resistant to a number of antimicrobial drug classes including aminoglycoside, fluoroquinolone, tetracycline and phenicol. Also found in UPM 260 genome were three intact prophages (Fels-1, Gifsy-2 and one unique prophage, mEp390). The genome housed four types of restriction-modification systems (RMS) and Type I-E subtype of CRISPR-Cas system. Two metal resistance operons (mer and cop) and six pathogenicity islands (SPIs) were also discovered in UPM 260 genome. The SPIs contributed mostly to the bacterial virulence properties since 1054 CDS were reported to be homologous to the virulence factors in the database VFDB. Conclusion This study benefits us specifically in the field of genome engineering where gene-based genetic manipulations can be applied in reducing the prevalence and pathogenicity in Salmonella.

The current method to detect antibody titre against infectious bursal disease virus (IBDV) in chickens is based on enzyme-linked immunosorbent assay (ELISA) using whole virus as coating antigen. Coating the ELISA plates requires a purified or at least semi-purified preparation of virus as antigen, which needs special skills and techniques. In this study, instead of using whole virus, recombinant protein of hexahistidine tag (His 6 tag) and VPX protein of IBDV expressed in E. coli was used as an alternative antigen to coat the ELISA plates. There was a good correlation coefficient (R 2 = 0.972) between the results of the ELISA using plates coated with monoclonal antibody against His 6 tag and those of the commercial IBDV ELISA kit. Hence, His 6 tag and VPX recombinant protein expressed in E. coli has the potential for the development of ELISA for the measurement of IBDV-specific antibody.