16 documents found, page 1 of 2

Changing human hair fibre colour and shape from the follicle

Introduction: Natural hair curvature and colour are genetically determined human traits, that we inten tionally change by applying thermal and chemical treatments to the fibre. Presently, those cosmetic methodologies act externally and their recurrent use is quite detrimental to hair fibre quality and even to our health. Objectives: This work represents a disruptive concept to modify natural hair colour and cur...

Peptideprotein interactions within human hair keratins

We selected 1235 decapeptides from human hair proteins encoded by human genes of keratins and keratin associated proteins. The peptides were linked to glass arrays and screened for their affinity towards a solution of human hair extracted keratin fraction. Based on the physicochemical properties of the peptides, ten variables were studied: content of different types of amino acid side chains (cysteine, hydropho...

Hair keratin molecular dynamics studies

[Excerpt] The keratin is a key element of the hair, nails and skin in vertebrates. Understand the keratin features such its assembling in the mentioned structures, its interactions with some compounds or mechanical properties is of great interest in the fight against some diseases or in the development and optimization of cosmetic products. Although molecular dynamics (MD) simulations provides unique informatio...

Straighten curly hair with keratin peptides

[Excerpt] Chemical straightening curly human hair fibres involves the use of strong reducing agents at alkaline pHs. These treatments damage the hair fibre, reduce the cross‐linking density and decrease hair’s  physico mechanical properties [1]. Human hair is made of keratin and the fixation of fibres shape involve the reduction and reformation of new disulphide bonds between keratin molecules. t is known that ...

Understanding the molecular basis behind hair morphology: development of new st...

Effect of a peptide in cosmetic formulations for hair volume control

Objective The capacity of hair to absorb water causes changes in its physical and cosmetic properties under different environmental conditions. Hence, the control of hair volume in variable relative humidity settings is an important topic in cosmetics. The behaviour of two types of hair, Caucasian and Asian, was studied regarding their volume change in different relative humidity conditions. The ability of a pe...

Changing the shape of hair with keratin peptides

Chemical straightening of curly human hair fibres involves the use of strong reducing agents at alkaline pH. Human hair is made of keratin, and the fixation of fibre shape involves the reduction and reformation of new disulphide bonds between keratin molecules. Here, we propose an alternative and green methodology using keratin peptide sequences (10-13 residues) derived from the human genome. In a previous stud...

Human hair and the impact of cosmetic procedures: a review on cleansing and sha...

Hair can be strategically divided into two distinct parts: the hair follicle, deeply buried in the skin, and the visible hair fiber. The study of the hair follicle is mainly addressed by biological sciences while the hair fiber is mainly studied from a physicochemical perspective by cosmetic sciences. This paper reviews the key topics in hair follicle biology and hair fiber biochemistry, in particular the ones ...

Assessment of liposome disruption to quantify drug delivery in vitro

Efficient liposome disruption inside the cells is a key for success with any type of drug delivery system. The efficacy of drug delivery is currently evaluated by direct visualization of labeled liposomes internalized by cells, not addressing objectively the release and distribution of the drug. Here, we propose a novel method to easily assess liposome disruption and drug release into the cytoplasm. We propose ...

Insights on the mechanical behavior of keratin fibrils

A computational molecular model of a truncated keratin protofibril (8 chains of hair keratin, PDB provided in Supplementary Material) was used, to run a series of steered molecular dynamics simulations obtaining strain-stress curves. These results were compared with experimental mechanical data on hair fibers. Our data demonstrate that the molecular dynamics simulations can model hair mechanical properties. Sim...