Highly pathogenic avian influenza (H5N1) in Myanmar, 2006-2010

Highly pathogenic avian influenza (HPAI) virus subtype H5N1 was first reported in Myanmar in 2006. In this study, we have characterized 6 HPAI (H5N1) viruses recovered from 2007-2010 as well as three additional available nucleotide sequences representing Myanmar AI outbreaks. Phylogenetic analysis showed that the Myanmar viruses belong to HPAI (H5N1) clades 7, 2.3.2 and 2.3.4. The result suggested that the HPAI (H5N1) viruses recovered from Myanmar had been introduced into the country by multiple introductions. Genetic analysis of the viruses confirmed the HPAI characteristics of the viruses.     

Transfollicular enhancement of methyl myristate loaded in cationic niosomes incorporated in hair lotion

Hair lotion containing methyl myristate loaded in cationic niosomes (HL-MMnio) composed of Brij72/cholesterol/DDAB at 7:3:0.65 molar ratio was developed. The remaining percentages of MM loaded in cationic niosomes in hair lotion were higher than free MM in hair lotion of about 1.2 times. The cumulative amounts in porcine skin and the receiver compartment of MM loaded in cationic niosomes incorporated in hair lotion were higher than those of free MM in hair lotion of 1.45 and 1.32 times, respectively. HL-MMnio showed very slightly irritation on rabbit skin, which was disappeared after 4 d. For melanogenesis induction in C57BL/6 mice with aged-induced grey body coat hairs, the highest pigmentation scores of HL-MMnio applied on the dorsal area were observed after 21 days, while hair lotion containing the free MM indicated after 35 days. This study has suggested that HL-MMnio was the high potential formulation for canities treatment.     

Potent Melanin Production Enhancement of Human Tyrosinase Gene by Tat and an Entrapment in Elastic Cationic Niosomes: Potential Application in Vitiligo Gene Therapy

Potent melanin production enhancement of human tyrosinase plasmid (pAH7/Tyr, P) in mouse melanoma cells (B₁₆F₁₀) by Tat peptide (T) and an entrapment in elastic cationic niosomes (E) was described. The E composed of Tween 61/cholesterol/dodecyl dimethyl ammonium bromide at 1:1:0.5 molar ratio was prepared by freeze‐dried emptying liposomes method. PE at P/E ratio of 1:160 w/w and TPE at T/P/E ratio of 0.125:1:160, 0.25:1:160, and 0.5:1:160 w/w/w were prepared. The final concentration of the plasmid in the study was 4 ng/μL. By sulforhodamine B assay, PE and TPE complexes showed slight or no cytotoxic effect. The cells transfected with TPE (0.5:1:160) exhibited the highest enhancement of tyrosinase enzyme activity of 11.82‐, 7.67‐, 5.07‐, and 6.29‐folds of control, P, PE, and TP (0.5:1) and melanin production of 13.03‐, 8.46‐, 5.36‐, and 6.58‐folds of control, P, PE, and TP (0.5:1), respectively. The elastic cationic niosomes demonstrated an increase in thermal stability of P at 4 ± 2, 25 ± 2, and 45 ± 2 °C. The vesicular size and the zeta potential values of PE and TPE complexes were slightly increased but still in the range of stable dispersion (out of ±30 mV). These results indicated the high potential application of the TPE complexes for further investigation for vitiligo gene therapy.     

Enhancement of gene expression and melanin production of human tyrosinase gene loaded in elastic cationic niosomes

Objectives Disturbance in the synthesis of tyrosinase might be one of the major causes of vitiligo. The enhancement of tyrosinase gene expression and melanin production by loading the plasmid in elastic cationic niosomes was investigated in tyrosinase gene knocked out human melanoma (M5) cells and in tyrosine‐producing mouse melanoma (B₁₆F₁₀) cells. Methods Niosomes composed of Tween 61/cholesterol/dimethyl dioctadecyl ammonium bromide at 1 : 1 : 0.5 molar ratio were prepared by the freeze‐dried empty liposomes method. The thin lipid film was redissolved in distilled water or 25% ethanol to obtain the non‐elastic or elastic cationic niosomes, respectively. Key findings The maximum loading of the plasmid in non‐elastic and elastic niosomes was 130 and 100 µg per 16 mg of the niosomal contents, respectively. The plasmid‐loaded elastic cationic niosomes exhibited high specific tyrosinase activity of 1.66 and 1.50 fold in M5 cells and 6.81 and 4.37 fold in B₁₆F₁₀ cells compared with the free plasmid and the plasmid‐loaded non‐elastic cationic niosomes, respectively. Conclusions This study has demonstrated not only the enhancement of the expression of human tyrosinase gene by loading in elastic cationic niosomes, but also the potential application of this gene delivery system for the further development of vitiligo gene therapy.     

Genetic characterization of influenza A virus subtype H12N1 isolated from a watercock and lesser whistling ducks in Thailand

Monitoring of influenza A virus (IAV) was conducted in wild bird species in central Thailand. Four IAV subtype H12N1 strains were isolated from a watercock (order Gruiformes, family Rallidae) (n = 1) and lesser whistling ducks (order Anseriformes, family Anatidae) (n = 3). All H12N1 viruses were characterized by whole-genome sequencing. Phylogenetic analysis of all eight genes of the Thai H12N1 viruses indicated that they are most closely related to the Eurasian strains. Analysis of the HA gene revealed the strains to be of low pathogenicity. This study is the first to report the circulation of IAV subtype H12N1 in Thailand and to describe the genetic characteristics of H12N1 in Eurasia. Moreover, the genetic information obtained on H12N1 has contributed a new Eurasian strain of H12N1 to the GenBank database.     

Anti-proliferative activities on HeLa cancer cell line of Thai medicinal plant recipes selected from MANOSROI II database

Ethnopharmacological relevance

The Thai/Lanna medicinal plant recipe database “MANOSROI II” contained the medicinal plant recipes of all regions in Thailand for the treatment of various diseases including anti-cancer medicinal plant recipes.

Aim of the study

To investigate anti-proliferative activity on HeLa cell lines of medicinal plant recipes selected from the Thai/Lanna medicinal plant recipe database “MANOSROI II”.

Materials and methods

The forty aqueous extracts of Thai/Lanna medicinal plant recipes selected from the Thai/Lanna medicinal plant recipe database “MANOSROI II” were investigated for anti-proliferative activity on HeLa cell line by SRB assay. The apoptosis induction by caspase-3 activity and MMP-2 inhibition activity by zymography on HeLa cell line of the three selected aqueous extracts, which gave the highest anti-proliferative activity were determined. Phytochemicals and anti-oxidative activities including free radical scavenging activity, inhibition of lipid peroxidation and metal chelating inhibition activities were also investigated.

Result

Sixty percentages of the medicinal plant recipes selected from “MANOSROI II” database showed anti-proliferative activity on HeLa cell line. The recipes of N031(Albizia chinensis (Osbeck) Merr, Cassia fistula L., and Dargea volubilis Benth.ex Hook. etc.), N039 (Nymphoides indica L., Peltophorum pterocarpum (DC.), and Polyalthia debilis Finet et Gagnep etc.) and N040 (Nymphoides indica L. Kuntze, Sida rhombifolia L., and Xylinbaria minutiflora Pierre. etc.) gave higher anti-proliferative activity than the standard anti-cancer drug, cisplatin of 1.25, 1.29 and 30.18 times, respectively. The positive relationship between the anti-proliferative activity and the MMP-2 inhibition activity and metal chelating inhibition activity was observed, but no relationship between the anti-proliferative activity and apoptosis induction, free radical scavenging activity and lipid peroxidation inhibition activity. Phytochemicals found in these extracts were alkaloids, flavonoids, tannins and xanthones, but not anthraquinones and carotenoids. The recipe N040 exhibited the highest anti-proliferative and MMP-2 inhibition on HeLa cancer cell line at 30 and threefolds of cisplatin, respectively (p<0.05), while recipe N031 gave the highest caspase-3 activity (1.29-folds over the control) (p<0.05).

Conclusion

This study has demonstrated that recipe N040 selected from MANOSROI II database appeared to be a good candidate with high potential for the further development as an anti-cancer agent.     

Transdermal Absorption Enhancement of N-Terminal Tat–GFP Fusion Protein (TG) Loaded in Novel Low-Toxic Elastic Anionic Niosomes

Elastic anionic niosomes (Tween 61/cholesterol/dicetyl phosphate at 1:1:0.05 molar ratio of 20 mM) with various concentrations of ethanol and edge activators sodium cholate (NaC) and sodium deoxycholate (NaDC) showed larger vesicular size (171.94 ± 63.52 – 683.17 ± 331.47 nm) and higher negative zeta potential (?6.45 ± 2.76 to ? 17.40 ± 2.51 mV) than the nonelastic anionic niosomes. The elasticity (deformability index) and entrapment efficiency of all elastic vesicles except the NaDC vesicles were higher than the nonelastic vesicles. The morphology, under transmission electron microscope, of elastic and nonelastic niosomes loaded and not loaded with Tat–green fluorescent protein fusion protein (TG) were in large unilamellar structure. TG loaded in elastic (1 mol% NaC) anionic niosomes gave the highest cell viability both in HT-29 (92.32 ± 3.82%) and KB cells (96.62 ± 5.96%), the highest cumulative amounts (62.75 ± 2.68 μg/cm²) and fluxes (10.46 ± 3.45 μg/cm²h) in receiving chamber in rat skin transdermal study by Franz diffusion cells. This study has not only indicated the synergistic enhancement effects of the Tat peptide and the niosomal delivery system on the cellular uptake and transdermal absorption of TG but also 1 mol% NaC as an edge activator to obtain a novel low-toxic elastic anionic niosomes for topical use of therapeutic macromolecules such as proteins, as well.     

Pandemic (H1N1) 2009 Virus on Commercial Swine Farm, Thailand

A swine influenza outbreak occurred on a commercial pig farm in Thailand. Outbreak investigation indicated that pigs were co-infected with pandemic (H1N1) 2009 virus and seasonal influenza (H1N1) viruses. No evidence of gene reassortment or pig-to-human transmission of pandemic (H1N1) 2009 virus was found during the outbreak.