The Influence of Surface Charge on the Antiviral Effect of Curcumin Loaded in Nanocarrier System.

BACKGROUND: Curcumin is a well-documented bioactive compound present in Curcuma sp., a tropical, medicinal plant. This substance exhibits broad-spectrum biological activities, including antivirus. Despite the lack of pharmaceutical properties of curcumin limits its clinical use. OBJECTIVE: This study aims to produce curcumin nanoemulsion with different surface charge (curcumin (+) nanoemulsion and curcumin (-) nanoemulsion) and to evaluate its physical characteristics, in vitro cell cytotoxicity, and antiviral activity against dengue virus (DENV) 1 and 2. METHODS: Two forms of nanoemulsion were prepared, which were differed from their surface charge through spontaneous procedure resulting in similar characteristics except for the zeta potential value. Cytotoxicity was determined using the RT-PCR method in the A549 cell line, and anti- DENV properties were determined by calculation of inhibitory concentration 50 (IC50) value. RESULTS: The positive charge of curcumin-loaded nanoemulsion showed a better effect in reducing the viral replication represented by a lower IC50 value. In addition, DENV-1 was more sensitive and responsive to curcumin as compared to DENV-2. CONCLUSION: Positive surface charge of curcumin-loaded nanoemulsion improves the antiviral effect of the curcumin, suggesting a promising approach for alternative treatment for dengue virus infection.

Heterogeneity of Mycobacterium tuberculosis strains in Makassar, Indonesia.

SETTING: Patients with suspected pulmonary tuberculosis (TB) visiting government TB diagnostic and treatment centres in Makassar City, South Sulawesi Province, Indonesia, from February to October 2008 were included in the study. OBJECTIVE: To determine the distribution of Mycobacterium tuberculosis genotypes in Makassar. DESIGN: Cross-sectional study. Spoligotyping, mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) and principal genetic grouping (PGG) were used to genotype the M. tuberculosis clinical isolates. RESULTS: Among 179 isolates derived from pulmonary TB patients, distribution of spoligotypes comprised the East Africa-Indian (30.2%), T (17.9%), H (12.3%) and Beijing (9.5%) lineages. Other lineages found in smaller proportions were the Latin American-Mediterranean, MANU, S and X lineages. Nineteen isolates (10.6%) could not be grouped into any of the reported lineages or shared types. Single nucleotide polymorphism analysis of katG(463) and gyrA(95) grouped these isolates primarily into PGG1 (9/19, 47%). CONCLUSION: Only a few genetically identical clustered isolates were identified within the 9-month study period, and most isolates were genetically diverse. Furthermore, 15 spoligopatterns identified in our study have not been reported previously. To our knowledge, this is the first comprehensive study describing genotypes of M. tuberculosis clinical isolates in Sulawesi.