What is a Caucasian 'fine' hair? Comparing instrumental measurements, self-perceptions and assessments from hair experts.

OBJECTIVE: To determine the various factors contributing to what Caucasian women describe as 'fine hair'. METHODS: Three complementary approaches were used, namely self-evaluation by the volunteer, assessment by a sensorial expert and instrumental measurements, in order to determine some of the possible parameters taken into account by Caucasian women when they describe the notion of fine hair. One hundred fifty one women of Caucasian origin participated in the study. They varied in age, and varied in that some considered themselves as having fine hair, and others not. The instrumental measurements carried out included hair diameter measurements, hair density measurements, hair breakage force, hair flexibility and scalp sebum levels. RESULTS: From six parameters defined initially, four parameters were found to be in common with the three approaches: hair abundance (density), hair thickness, hair resistance and the volume of the hair on the head. The commonly used term 'body' was only common to self and expert evaluation, whereas the influence of curliness was only common to expert evaluation and instrumental measurements. CONCLUSIONS: This study has shown close agreement between sensorial and instrumental findings, and also illustrates how the women participating can subtly and adequately describe their own hair. It is important to note that the words 'fine hair' describes a lot more than just physically thin hair fibres. Ageing is an additional factor that clearly impacts certain parameters associated with 'fine hair' among the volunteers.

In situ hybridization and cytofluorometric analysis of cytokine mRNA during in vitro activation of human T cells.

We present an original method for in situ hybridization (ISH) using non isotopic probes and flow cytometry analysis that permits rapid detection of lymphokine transcripts at single cell level in an in vitro activated human Jurkat T cell line and in peripheral blood T cell subsets. After PMA and either ionomycin or ConA stimulation, cells were fixed and hybridized with digoxigenin (DIG)-labelled RNA antisense or sense probes specific for IL-2 and IFN-gamma. The level of cytokine gene expression in individual cells was visualised using FITC-conjugated anti-DIG antibody, and the resultant signal was analysed by flow cytometry. IL-2 mRNA was first detected in activated Jurkat T cells. Addition of cycloheximide 4 hours after the beginning of stimulation increased both the frequency of labelled cells and the amount of mRNA per cell, as determined by the mean fluorescence intensity. The specificity and sensitivity of IL-2 mRNA detection were tested by comparison with Northern blot analysis and in situ hybridization (ISH) with immuno-cytochemical staining. IL-2 and IFN-gamma mRNA were detectable in PBMC as early as 3 hours after in vitro stimulation with PMA and ionomycin. The frequency of positive cells and the amount of mRNA per cell peaked at 6-8 hours, when the percentages of IL-2 and IFN-gamma mRNA-containing cells reached 30-40% and 15-20%, respectively. The two lymphokines were expressed in both CD4+ and CD8+ T cells, but the frequency of IL-2 expressing cells and the amount of IL-2 mRNA per cell were higher in CD4+ (60%) than in CD8+ T cells (25%), whereas IFN-gamma were preferentially transcribed by CD8+ T cells (40%). The results obtained by this method were in accordance with the data obtained by Northern blot analysis, with cellular protein content estimated by immuno-fluorescence staining, and with IL-2 titration by bioassay. We compared the performance of this method with ISH using radioactive probes.