The ratios of the zwitterion form to the uncharged form of glycine, KD=[NH3+CH2COO−]/[NH2CH2COOH], were determined in mixtures of water with methanol, ethanol, t-butyl alcohol, dimethyl sulfoxide, acetonitrile, 1,4-dioxane, N,N-dimethylformamide, and tetrahydrofuran. The value of In KD decreases and, therefore, ΔG298° increases, with the increase in the mole fractions of the organic solvents. The plots of ΔG° vs. reciprocal of the dielectric constants of the alcoholic mixtures are simply linear indifferent to the kind of alcohols, indicating that this relation obeys the Scatchard equation and that the free energy change of the process of the intramolecular protonation in glycine is controlled mainly by electrostatic interaction, especially by the entropy change associated with the preferential solvation around the charged amino and carboxyl groups.
Dialkyl ethers and alkyl fluoroalkyl ethers are obtained in excellent yields by the reaction of alcohols and carbonyl compounds in the presence of Pd/C under the atmospheric pressure of hydrogen, when water produced by the reaction is continuously removed by bubbling hydrogen through the reaction mixture.
The relationship between lip roughness and the CER profile was clarified for the first time. The results suggest that not only the level of total CERs but also the specific CER species and their carbon numbers affect the maintenance of SC function.
Age-related changes with regard to SC functions, viscoelasticity and color of the lips have been clarified for the first time, and it is clear that these changes are related to problems of the lips. Compared with the cheeks, differences with the lips are more apparent.
OBJECTIVE: Since skin on the lips has a lower water content in the stratum corneum (SC) and a higher transepidermal water loss (TEWL) value than skin on the cheek, the lips are usually very dry and rough areas. Therefore, a lip balm approach to increase occlusivity of the lips is generally used to reduce water loss. Although there have been reports of an improvement effect on lip roughness by specific care agents, differences in the effects due to the occlusivity of a formulation without a specific care agent have not been reported. The purpose of this study was to clarify the improvement effect on dryness and roughness of the lips by a highly occlusive formulation consisting of a combination of common oil and wax, not by a specific care agent. METHODS: Twenty Japanese female subjects with normal skin (age range 20-39 years; mean 28.1) were enrolled in this study. A 4-week continuous use test was conducted using samples with low and high occlusivity. The degree of lip roughness and wrinkles was scored, the hollow index was assessed using ANTERA 3D images, and values of capacitance and TEWL were measured. RESULTS: The hollow index was significantly correlated with both the appearance roughness score and the wrinkle score. The sample with high occlusivity showed significant improvement in the appearance roughness score, wrinkle score, the hollow index and capacitance of the SC. In a comparison between the groups of samples with different occlusive properties, a significant improvement effect in rough appearance was seen in subjects using the highly occlusive formulation. CONCLUSION: The hollow index assessed by ANTERA 3D imaging allowed the objective evaluation of the improvement in appearance. In the case of continuous use of the highly occlusive formulation, an improvement of capacitance in the SC, which is most correlated with lip roughness, was obtained after 2 and 4 weeks. These results demonstrate for the first time that a highly occlusive formulation is effective in improving the roughness of the lips, and this effect is due to the difference in the occlusive property not by a specific care agent.
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