Changing human hair fibre colour and shape from the follicle.

INTRODUCTION: Natural hair curvature and colour are genetically determined human traits, that we intentionally 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 curvature. We aim to model the fibre phenotype as it is actively produced in the follicle through the topical delivery of specific bioactive molecules to the scalp. METHODS: Transcriptome differences between curly and straight hairs were identified by microarray. In scalp samples, the most variable transcripts were mapped by in situ hybridization. Then, by using appropriate cellular models, we screened a chemical library of 1200 generic drugs, searching for molecules that could lead to changes in either fibre colour or curvature. A pilot-scale, single-centre, investigator-initiated, prospective, blind, bilateral (split-scalp) placebo-controlled clinical study with the intervention of cosmetics was conducted to obtain a proof of concept (RNEC n.92938). RESULTS: We found 85 genes transcribed significantly different between curly and straight hair, not previously associated with this human trait. Next, we mapped some of the most variable genes to the inner root sheath of follicles, reinforcing the role of this cell layer in fibre shape moulding. From the drug library screening, we selected 3 and 4 hits as modulators of melanin synthesis and gene transcription, respectively, to be further tested in 33 volunteers. The intentional specific hair change occurred: 8 of 14 volunteers exhibited colour changes, and 16 of 19 volunteers presented curvature modifications, by the end of the study. CONCLUSION: The promising results obtained are the first step towards future cosmetics, complementary or alternative to current methodologies, taking hair styling to a new level: changing hair from the inside out.

Peptide-protein 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, hydrophobic, polar, basic, acidic, aromatic rings, amide, alcohol side chains), isoelectric point, and net charge. We found differences statistically significant on the binding affinity of peptides based on their content of cysteine, hydrophobic and polar amino acids, mainly containing alcohols. These results point to the formation of hydrophobic interactions and disulfide bonds between small peptides and human hair keratins as the main driving forces for the interaction of possible cosmetic peptides, namely designed to strength human hair. As so, our results enlighten the nature of the interaction of keratin based materials with human hair, which are claimed to enhance hair fiber strength, and enable a more directed and sustained hair care peptide design.

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. Simulations done in vacuum showed a better agreement with experimental Young's Modulus (YM) values. The role of hydrogen bonds and the secondary structure of keratin on the mechanical properties was evaluated in detail. The incubation with a fragment of one surfactant protein, the SPD-2 peptide (QAAFSQ), showed the improvement of YM of the hair keratin either by simulations and experimental data. For the first, our research provides mechanistic insights on mechanical microscopic properties of keratin protofibrils through molecular dynamics simulations.

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 the encapsulation of the cationic dye Hoechst 34580 to detect an increase in blue fluorescence due to its specific binding to negatively charged DNA. For that, the dye needs to be released inside the cell and translocated to the nucleus. The present approach correlates the intensity of detected fluorescent dye with liposome disruption and consequently assesses drug delivery within the cells.

Prevalência de casos de Mycoplasma hominis e Ureaplasma urealyticum nas secreções endocervicais e urinas de primeiro jato em Laboratório de Análises Clínicas de Brusque - SC / Prevalence of cases Mycoplasma hominis and Ureaplasma urealyticum in endocervical secretions and first jet of urine in a laboratory of clinic analysis in Brusque - SC

Mycoplasma hominis e Ureaplasma urealyticum são os menores e mais simples procariontes que conseguem ter vida livre na natureza; desprovidos de parede celular, possuem apenas uma membrana lipoprotéica. Podem ser isolados do trato geniturinário de homens e mulheres assintomáticos como comensais mas, também, podem ser considerados agentes de uretrites, prostatites, epididimites, vaginoses, doença inflamatória pélvica, abortos, partos prematuros, corioamnionites, salpingites, febre puerperal, infertilidade, pielonefrites e infecções no recém-nascido. O presente trabalho visou estabelecer a prevalência de M. hominis e U. urealyticum em secreções endocervicais e urinas de primeiro jato no Laboratório Hoffmann de Análises Clínicas de Brusque, Santa Catarina, no período de agosto a dezembro de 2003. Foram analisadas 62 secreções endocervicais e 32 urinas de primeiro jato; utilizando o Kit para Micoplasma (Newprov), que permite identificação, quantificação e crescimento de colônias. Desenvolveram crescimento 25,8% das secreções endocervicais e 28,1% das urinas de primeiro jato, foi verificada presença de abundantes leucócitos em um número significativo de amostras e encontrou-se, nas secreções endocervicais, associação dos micoplasmas com outras patologias. Os resultados obtidos revelaram que o M. hominis e o U. urealyticum são patógenos importantes e devem ser pesquisados, identificados e quantificados como exames de rotina nos laboratórios de análises clínicas.

Mycoplasma hominis and Ureaplasma urealyticum are the smallers and the simplest procariont that achieves having a life free in the nature, without cellular wall, owning only a lipoprotein membrane. They can be alone in men and women geniturinariun treatment bringing no symptoms as comensals, but they can be considered uretrits agents, prostatits, epididimits, vaginoses, pelvic inflammation illness, abortion, premature chilbirth, corioamnionits, salpingits, puerperal fever, no possibility of having children, pielonefrits and infections in babies that have just borned. This present article tried to estabilish the prevalence of Mycoplasma hominis and Ureaplasma urealyticum in endocervical secretions and first jet of urine in the Hoffmann laboratory of clinic analysis located in Brusque, Santa Catarina, during the period from August to December of 2003. We analyzed 62 endocervical secretions and 32 first jet of urine, using the Kit for “Micoplasma” (Newprov), that permited the identification, qualification and the colonies growth. 25,8% of the endocervical secretions and 28,1% of the first jet of urine desenvolved a growth, which was noticed the appearance of abundats white cells in a meaningful number of samples and was found, in the endocervical secretions, the association of micoplasm with others pathologies. The results gotten, exposed that M. hominis and U. Urealyticum are impostants pathogen and should be searched, identified and qualidified as daly exams in laboratorys of clinic analysis.