Alleviation of hand-skin roughness after use of alcohol-based hand rub with inhibitory effects on Staphylococcus aureus-producing δ-toxin.

INTRODUCTION: Staphylococcus aureus colonizes rough regions of the skin of the hand. Healing of S. aureus-mediated wounds is promoted by the application of RNA III inhibiting peptide, which inhibits the production of S. aureus virulence factors, including δ-toxin. Herein, we investigated the level of hand-skin roughness in healthcare professionals after they used an alcohol-based hand rub containing polyoxyethylene lauryl ether (formulation E), which inhibits S. aureus δ-toxin production. METHODS: The inhibition rate of S. aureus δ-toxin production by hand rubs, including formulation E, was calculated by quantifying S. aureus δ-toxin concentration in culture medium using high-performance liquid chromatography. Healthcare professionals used formulations E or S (reference alcohol-based hand rub) for 4 weeks. The surface evaluation of the scaliness (SEsc) value was used as an indicator of hand skin roughness. The ΔSEsc value was calculated by subtracting the SEsc value before using the alcohol-based hand rub from the SEsc value 4 weeks after use. RESULTS: The inhibition rates of S. aureus δ-toxin production by formulations E and S were 43% and 10%, respectively. Formulation E significantly reduced ΔSEsc. The difference in ΔSEsc values after using formulations E and S was significant. CONCLUSIONS: The inhibitory effect on S. aureus δ-toxin production was higher with formulation E than with formulation S. Compared to formulations S, formulation E was effective at reducing scaliness and alleviating hand-skin roughness. Furthermore, the inhibitory effect of formulation E on S. aureus δ-toxin production could be associated with a reduction in scaliness and alleviation of hand-skin roughness.

Effects of Polypropylene Glycol at Very Low Concentrations on Rheological Properties at the Air-Water Interface and Foam Stability of Sodium Bis(2-ethylhexyl)sulfosuccinate Aqueous Solutions.

The present study investigates the effects of very low concentrations of polypropylene glycol (PPG) on the rheological properties of sodium bis(2-ethylhexyl)sulfosuccinate (AOT) aqueous solutions at the surface for the precise control of foam properties. Langmuir trough experiments and Brewster angle microscopy (BAM) of the AOT monolayer on the surfaces of PPG aqueous solutions indicated that a very low concentration of PPG increased the number of AOT molecules at the surface. Viscoelastic behaviors at the surface and surface tension isotherms in mixed aqueous solutions of AOT and PPG revealed that AOT interacted with PPG in the surface and bulk phase. A modified Ross-Miles method was performed to assess the foam stabilities of AOT aqueous solutions with and without PPG. The stabilization of foam by PPG was attributed to the rheological properties of AOT aqueous solutions at the surface.

Evaluation of repetitive-PCR and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for rapid strain typing of Bacillus coagulans.

In order to establish rapid and accurate typing method for Bacillus coagulans strains which is important for controlling in some canned foods and tea-based beverages manufacturing because of the high-heat resistance of the spores and high tolerance of the vegetative cells to catechins and chemicals, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and repetitive-PCR (rep-PCR) were evaluated. For this purpose, 28 strains of B. coagulans obtained from various culture collections were tested. DNA sequence analyses of the genes encoding 16S rRNA and DNA gyrase classified the test strains into two and three groups, respectively, regardless of their phenotypes. Both MALDI-TOF MS and rep-PCR methods classified the test strains in great detail. Strains classified in each group showed similar phenotypes, such as carbohydrate utilization determined using API 50CH. In particular, the respective two pairs of strains which showed the same metabolic characteristic were classified into the same group by both MALDI-TOF MS and rep-PCR methods separating from the other strains. On the other hand, the other strains which have the different profiles of carbohydrate utilization were separated into different groups by these methods. These results suggested that the combination of MALDI-TOF MS and rep-PCR analyses was advantageous for the rapid and detailed typing of bacterial strains in respect to both phenotype and genotype.