Variations of scalp, pubic and axillary hair.
01 Jan 2012-Anthropologischer Anzeiger (Anthropol Anz)-Vol. 69, Iss: 1, pp 117-125
TL;DR: It is envisaged that variability in histomorphological and quantitative traits in different areas of human could be one of the important criteria for personal identification in forensic research.
Abstract: Hair examinations and comparisons conducted by forensic scientists often provide investigative and associative information. Apart from its length and its natural color, hair displays a morphologic diversity both macroscopically and microscopically. Pseudogenization of
TL;DR: In literature, there are various studies about hair that take into consideration different aspects within many fields of science, including biology, dermatology, cosmetics, forensic sciences, and medicine.
Abstract: Background Hair is a unique character of mammals and has several functions, from protection of the skin to sexual and social communication. In literature, there are various studies about hair that take into consideration different aspects within many fields of science, including biology, dermatology, cosmetics, forensic sciences, and medicine. Methods We carried out a search of studies published in PubMed up to 2013. Results In this review, we summarized the principal anatomical and physiological aspects of the different types of human hair, and we considered the clinical significance of the different structures and the distribution of the hair in the human body. Conclusion This review could be the basis for improvement and progression in the field of hair research.
TL;DR: The evolution of human hair types is discussed, focusing in particular on afro‐textured hair, and the different methods employed to straighten this hair type, including chemical straightening are discussed.
Abstract: The culturally engrained practice of 'relaxing' afro-textured hair has been linked with hair and scalp disorders. Herein, we discuss the evolution of human hair types, focusing in particular on afro-textured hair. We explore the biological features of this hair type, and discuss the different methods employed to straighten afro-textured hair, focusing in particular on chemical straightening. We also examine clinical, anthropological, and psychological issues associated with this latter practice. Examples of common scalp pathologies associated with chronic hair relaxing, such as alopecia, hair breakage, caustic burns and irritant contact dermatitis, are also highlighted. The data presented herein should enable clinicians to engage in culturally appropriate discussions with their patients about issues of appearance and conformity.
TL;DR: A modeling approach to the investigation of human hair perception using computer-generated, virtual (rendered) human hair is presented, suggesting that hair is a salient feature of human physical appearance, which contributes to the perception of beauty.
Abstract: The social significance of physical appearance and beauty has been documented in many studies. It is known that even subtle manipulations of facial morphology and skin condition can alter people’s perception of a person’s age, health and attractiveness. While the variation in facial morphology and skin condition cues has been studied quite extensively, comparably little is known on the effect of hair on social perception. This has been partly caused by the technical difficulty of creating appropriate stimuli for investigations of people’s response to systematic variation of certain hair characteristics, such as colour and style, while keeping other features constant. Here, we present a modelling approach to the investigation of human hair perception using computer-generated, virtual (rendered) human hair. In three experiments, we manipulated hair diameter (Experiment 1), hair density (Experiment 2), and hair style (Experiment 3) of human (female) head hair and studied perceptions of age, health and attractiveness. Our results show that even subtle changes in these features have an impact on hair perception. We discuss our findings with reference to previous studies on condition-dependent quality cues in women that influence human social perception, thereby suggesting that hair is a salient feature of human physical appearance, which contributes to the perception of beauty.
TL;DR: Hair keratin K37 may be ideally suited to serve as a pathfinder for the elucidation of an altered androgen metabolism not only in occipital hairs follicles but also in follicles of other scalp regions.
Abstract: morphology nor the growth rate of the cultured follicles (Fig. 2a,b). In contrast, DHT but not testosterone led to a statistically significant 10 1-fold upregulation of the KRT37 gene, while the gene expression of KRT25 and KRT31 was not affected by the androgens. Indeed, the gene expression of SRD5A1 and SRD5A2 remained lower in cultured occipital hair follicles regardless of androgens (average DCt against RPLP0 by quantitative PCR was 6 2 and 15 2, respectively) (Fig. 2c). Accordingly, at the protein level, a significant K37 induction was clearly demonstrable in the medulla of DHT-treated but not testosterone-treated follicles (compare Fig. 2d, e1–e4, f1, f2), while the constitutive medullar keratin K75 remained insensitive to DHT (Fig. 2g, h1, h2). In line with findings in DHTexposed cultured dermal papilla cells from occipital hair follicles as well as in human beard hair follicles, IIF revealed a slight upregulation of AR expression in the nuclei of cells of the dermal papilla and the lower medulla of DHT-treated hair follicles (Fig. 2i–j′). Taken together, we describe two principal differences between the medulla of androgen-independent occipital and androgen-dependent sexual hairs. Firstly, occipital hairs do not contain genuine cortex cells within their medulla – a feature which is most probably related to the smaller diameter of the occipital hair shaft and its medulla. Secondly, occipital hairs exhibit the same complex keratin pattern as sexual hairs except for the expression of medullar keratin K37. Considering, however, that K37 expression can be induced in medulla cells in vitro through external DHT but not testosterone supply, this suggests that the androgen-insensitivity of occipital hair follicles in vivo goes back to the low expression of 5a-reductases, which results in the inability to synthesize DHT from its precursor testosterone in their dermal papilla and medulla cells. Hair keratin K37 may therefore be ideally suited to serve as a pathfinder for the elucidation of an altered androgen metabolism not only in occipital hairs follicles but also in follicles of other scalp regions.
TL;DR: This case serves as a reminder that the presence of cutaneous lesions elsewhere, while a useful clue, may also mislead the unwary when diagnosing cicatricial alopecias.
Abstract: diagnosis simpler despite the history of DLE of the scalp. Difficulty would arise if a patient presented with scarring alopecia due to LPP, rather than typical FFA, which may go unrecognized due to diagnostic overshadowing given a history of DLE. Similarly, a patient with known LP presenting with scarring alopecia should not be assumed to have LP-induced hair loss. This case serves as a reminder that the presence of cutaneous lesions elsewhere, while a useful clue, may also mislead the unwary when diagnosing cicatricial alopecias. A comprehensive clinical and pathological assessment proforma has been published which may be of use in aiding diagnosis and management of patients with challenging cicatricial alopecias.