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Metallothioneins (MTs) are small proteins that coordinate d‐block metal ions in sulfur‐metal clusters to control metal ion concentrations within the cell. Here we study metal cluster formation in the MT of the periwinkle Littorina littorea (LlMT) by nuclear magnetic resonance (NMR). We demonstrate that the three Cd2+ ions in each domain are taken up highly cooperatively, that is, in an all‐or‐none fashion, with a four‐ to six‐fold higher affinity for the C‐terminal domain. During the transfer of metal ions from Cd2+‐loaded MT to apo MT, Cd2+ is most efficiently transferred from the metalated protein to the apo C‐terminal domain. This behavior might be connected to unique structural motifs in the C‐terminal domain, such as two double‐CXC motifs and an increased proportion of positively charged residues. In Cd2+/Zn2+ metal exchange experiments, the N‐terminal domain displayed the most efficient inter‐molecular metal exchange. Amide hydrogen exchange reveals fewer protected amides for the N‐terminal domain, suggesting the structure might more easily "open up" to facilitate metal exchange. Experiments with a physical separation of donor and acceptor species demonstrate that metal exchange and transfer require protein–protein contacts. These findings provide insights into the mechanism of metal uptake and metal transfer, which are important processes during metal detoxification in snail MTs. [ABSTRACT FROM AUTHOR]

The article describes the use of naturally derived styling polymers with heat protection properties for hair cosmetic products. Ashland's protected Styleze ™ es polymer line offers an excellent sustainability profile and performance profile. The polymers protect the hair from daily styling damage and enable the development of products for unique individual hairstyles. A new technology called Styleze es-forza is introduced, which not only allows for weather-resistant styling but also has thickening properties and can reduce the use of additional thickeners. The data shows that the hair can be protected from the negative effects of high-temperature styling devices through the use of this technology. [Extracted from the article]

As more and more consumers make eco-conscious decisions, demand for sustainable, biodegradable cosmetics is increasing, and hair care is no exception. Hair styling products are performance-driven, with customers expecting the eco-friendly product offerings to deliver equal or superior performance as their traditional synthetic counterparts. Ashland’s proprietary Styleze™ es (eco-styler) polymer line is plant-derived with an exceptional performance and sustainability profile. These polymers deliver an outstanding styling and sensorial experience, giving formulators the ability to create products for unique and personalized hair styles, that protect hair from the everyday grooming damage. [ABSTRACT FROM AUTHOR]

Metallothioneins (MTs) are small proteins that coordinate d-block metal ions in sulfur-metal clusters to control metal ion concentrations within the cell. Here we study metal cluster formation in the MT of the periwinkle Littorina littorea (LlMT) by nuclear magnetic resonance (NMR). We demonstrate that the three Cd 2+ ions in each domain are taken up highly cooperatively, that is, in an all-or-none fashion, with a four- to six-fold higher affinity for the C-terminal domain. During the transfer of metal ions from Cd 2+ -loaded MT to apo MT, Cd 2+ is most efficiently transferred from the metalated protein to the apo C-terminal domain. This behavior might be connected to unique structural motifs in the C-terminal domain, such as two double-CXC motifs and an increased proportion of positively charged residues. In Cd 2+ /Zn 2+ metal exchange experiments, the N-terminal domain displayed the most efficient inter-molecular metal exchange. Amide hydrogen exchange reveals fewer protected amides for the N-terminal domain, suggesting the structure might more easily "open up" to facilitate metal exchange. Experiments with a physical separation of donor and acceptor species demonstrate that metal exchange and transfer require protein-protein contacts. These findings provide insights into the mechanism of metal uptake and metal transfer, which are important processes during metal detoxification in snail MTs., (© 2024 The Author(s). Protein Science published by Wiley Periodicals LLC on behalf of The Protein Society.)

In this study, digital photography in combination with image analysis was used to measure the luster of several lipstick formulations containing varying amounts and types of polymers. A weighed amount of lipstick was applied to a mannequin's lips and the mannequin was illuminated by a uniform beam of a white light source. Digital images of the mannequin were captured with a high-resolution camera and the images were analyzed using image analysis software. Luster analysis was performed using Stamm (L(Stamm)) and Reich-Robbins (L(R-R)) luster parameters. Statistical analysis was performed on each luster parameter (L(Stamm) and L(R-R)), peak height, and peak width. Peak heights for lipstick formulation containing 11% and 5% VP/eicosene copolymer were statistically different from those of the control. The L(Stamm) and L(R-R) parameters for the treatment containing 11% VP/eicosene copolymer were statistically different from these of the control. Based on the results obtained in this study, we are able to determine whether a polymer is a good pigment dispersant and contributes to visually detected shine of a lipstick upon application. The methodology presented in this paper could serve as a tool for investigators to screen their ingredients for shine in lipstick formulations.