Several loop-mediated isothermal amplification (LAMP) assays have been developed to detect common causative pathogens of bacterial meningitis (BM). However, no LAMP assay is reported to detect Streptococcus agalactiae and Streptococcus suis, which are also among common pathogens of BM. Moreover, it is laborious and expensive by performing multiple reactions for each sample to detect bacterial pathogen. Thus, we aimed to design and develop a single-tube LAMP assay capable of detecting multiple bacterial species, based on the nucleotide sequences of the 16S rRNA genes of the bacteria. The nucleotide sequences of the 16S rRNA genes of main pathogens involved in BM were aligned to identify conserved regions, which were further used to design broad range specific LAMP assay primers. We successfully designed a set of broad range specific LAMP assay primers for simultaneous detection of four species including Staphylococcus aureus, Streptococcus pneumoniae, S. suis and S. agalactiae. The broad range LAMP assay was highly specific without cross-reactivity with other bacteria including Haemophilus influenzae, Neisseria meningitidis and Escherichia coli. The sensitivity of our LAMP assay was 100-1000 times higher compared with the conventional PCR assay. The bacterial species could be identified after digestion of the LAMP products with restriction endonuclease DdeI and HaeIII.

The process of enzyme assisted extraction of essential oil from the leaves and branches of the Vietnamese aromatic plant Cinnamomum cassia was studied and optimized using a Box-Wilson central composite design consisting of 05 independent variables (pH, temperature T, time τ, concentration of the enzyme Laccase, and concentration of the enzyme Cellic Htec2) and two dependent variables (reducing sugar and yield of essential oil). Second-order polynomial equations were obtained for the responses, which fitted well with the experimental data. Optimal conditions for oil yield were found at pH = 5.2; T = 440C; τ = 5h30'; Laccase = 0.42 ml/g, and Cellic Htec2 = 1.15%. The experimental value (0.982% oil yield) was close to the predicted value (0.978%). The application of enzyme assisted extraction  in combination with optimization using response surface methodology substantially improved the oil yield as compared with traditional method.

Two new guaiane sesquiterpene lactones, vulgarolides A and B (1 and 2), were isolated from Artemisia vulgaris aerial parts using various chromatographic separations. The structure elucidation was performed by combination of spectroscopic experiments including 1D and 2D NMR, HR ESI MS, and CD. Their in vitro cytotoxic activities against five human cancer cell lines were also evaluated using SRB method.

In this paper we firstly proved that Mobile IP protocols are designed for mobility but not for session continuity. In contradiction, mSCTP (mobile Stream Control Transmission Protocol) appears to be the best protocol with regard to session continuity support, however it does not support location management mechanisms, thus context-aware QoS as well as other mechanisms based on knowledge of location are hardly accommodated. On the other hand, the standardized IP Multimedia Subsystem (IMS) solution initially introduced by 3GPP adopts the policy-based QoS model to map user's subscription to a pre-defined QoS level, to apply service-based charging and to prevent Theft-of-Service. In this article we propose a new approach that integrates mSCTP into IMS networks to facilitate session continuity and to provide mechanisms for service control. It is realized by a proxy based on mSCTP (mobile Stream Control Transmission Protocol) that acts as an anchor point for soft vertical handover of mobile nodes, which have multiple physical interfaces (e.g., WLAN/UMTS). The mSCTP-based proxy also supports QoS provisioning and adaptation for the mobile nodes when moving in a heterogeneous wireless environment. Results show that the signaling cost for handover in our approach can be up to 23 times smaller than that in the conventional approach.

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