Baumann Skin Type in the Korean Male Population.

BACKGROUND: Research into the Baumann skin type (BST) has recently expanded, with growing interest in the development of an efficient and effective skin type classification system for better understanding of this skin condition. OBJECTIVE: We aimed to identify male-specific skin type characteristics with investigation into the distribution of BST by age and region in the Korean male population and to determine the intrinsic and extrinsic factors related to skin type. METHODS: A questionnaire was administered to collect information about age, region, working behavior, drinking behavior, smoking behavior, usual habit of sun protection, medical history, and the BST which consisted of four parameters; oily (O) or dry (D), sensitive (S) or resistant (R), pigmented (P) or non-pigmented (N), and wrinkled (W) or tight (T). RESULTS: We surveyed 1,000 Korean males aged between 20 and 60 years who were divided equally by age and region. Of the total respondents, OSNW type accounted for the largest percentage and ORPW type the lowest. In terms of Baumann parameters, O type was 53.5%, S type was 56.1%, N type was 84.4% and W type was 57.5%. Several behavioral factors were found to have various relationships with the skin type. CONCLUSION: The predominant skin type in the Korean male respondents was OSNW type, and the distribution of skin types with regards to age and region was reported to be distinct. Therefore, skin care should be customized based on detailed skin types considering the various environmental factors.

Inhibition of P-glycoprotein by natural products in human breast cancer cells.

Multidrug resistance (MDR) is one of the most significant obstacles in cancer chemotherapy. One of the mechanisms involved in the development of MDR is the over-expression of P-glycoprotein (P-gp). It is widely known that natural compounds found in vegetables, fruits, plant-derived beverages and herbal dietary supplements not only have anticancer properties, but may also modulate P-gp activity. Therefore, the purpose of this investigation was to examine the effects of naturally occurring products on P-gp function in human breast cancer cell lines, MCF-7 (sensitive) and MCF-7/ADR (resistant). The accumulation of daunomycin (DNM), a P-gp substrate, was greater in the sensitive cells compared to the resistant cells, while the efflux of DNM was higher in the resistant cells compared to the sensitive cells over a period of 2 h. The IC50 value of DNM in the resistant cells was about 22 times higher than that in the sensitive cells, indicating an over-expression of P-gp in the resistant cells, MCF-7/ADR. All of the compounds tested, with the exception of fisetin, significantly decreased the IC50 value of DNM. Biochanin A showed the greatest increase in [3H]-DNM accumulation, increasing by 454.3 +/- 19.5% in the resistant cells, whereas verapamil, the positive control, increased the accumulation by 229.4 +/- 17.6%. Also, the accumulation of [3H]-DNM was increased substantially by quercetin and silymarin while it was reduced by fisetin. Moreover, biochanin A, silymarin, and naringenin significantly decreased DNM efflux from MCF-7/ADR cells compared with the control. These results suggest that some flavonoids such as biochanin A and silymarin may reverse MDR by inhibiting the P-gp function.

Immunoliposomes carrying plasmid DNA: preparation and characterization.

The objective of this study was to characterize immunoliposomes carrying plasmid DNA with optimal encapsulation efficiency and antibody density. Plasmid DNA was encapsulated by the freezing/thawing method into liposomes composed of POPC (1-palmitoyl-2-oleoyl-sn-glycerol-3-phosphocholine), DDAB (didodecyl dimethyl ammonium bromide), DSPE-PEG 2000 (distearoyl phosphatidyl ethanolamine polyethylene glycol 2000) and DSPE-PEG 2000-maleimide. The liposomes carrying plasmid DNA were extruded through two stacked polycarbonate filters, of different pore size, to control the liposome size. Then, rat IgG molecules were conjugated to the liposomes. The immunoliposomes containing plasmid DNA were separated from the free plasmid DNA and unconjugated IgG by Sepharose CL-4B column chromatography. The DNA amount encapsulated was affected by DDAB (cationic lipid) concentration, the initial amount of plasmid DNA between 10 microg and 200 microg, the total lipid amount and plasmid DNA size, but not significantly by liposome size. By varying the ratio of DSPE-PEG 2000-maleimide to IgG, the number of IgG molecules per liposome was changed significantly.