Hair Coverage Research Articles

Gene loss in keratinization programs accompanies adaptation of cetacean skin to aquatic lifestyle.

Gene loss in keratinization programs accompanies adaptation of cetacean skin to aquatic lifestyle.

A sustainable slashing industry using biodegradable sizes from modified soy protein to replace petro-based poly(vinyl alcohol).

Biodegradable sizing agents from triethanolamine (TEA) modified soy protein could substitute poly(vinyl alcohol)(PVA) sizes for high-speed weaving of polyester and polyester/cotton yarns to substantially decrease environmental pollution and impel sustainability of textile industry. Nonbiodegradable PVA sizes are widely used and mainly contribute to high chemical oxygen demand (COD) in textile effluents. It has not been possible to effectively degrade, reuse or replace PVA sizes so far. Soy protein with good biodegradability showed potential as warp sizes in our previous studies. However, soy protein sizes lacked film flexibility and adhesion for required high-speed weaving. Additives with multiple hydroxyl groups, nonlinear molecule, and electric charge could physically modify secondary structure of soy protein and lead to about 23.6% and 43.3% improvement in size adhesion and ability of hair coverage comparing to unmodified soy protein. Industrial weaving results showed TEA-soy protein had relative weaving efficiency 3% and 10% higher than PVA and chemically modified starch sizes on polyester/cotton fabrics, and had relative weaving efficiency similar to PVA on polyester fabrics, although with 3- 6% lower add-on. In addition, TEA-soy sizes had a BOD5/COD ratio of 0.44, much higher than 0.03 for PVA, indicating that TEA-soy sizes were easily biodegradable in activated sludge.

Why care about linear hair growth rates (LHGR)? a study using in vivo imaging and computer assisted image analysis after manual processing (CAIAMP) in unaffected male controls and men with male pattern hair loss (MPHL).

The words "hair growth" frequently encompass many aspects other than just growth. Report on a validation method for precise non-invasive measurement of thickness together with linear hair growth rates of individual hair fibres. To verify the possible correlation between thickness and linear growth rate of scalp hair in male pattern hair loss as compared with healthy male controls. To document the process of validation of hair growth measurement from in vivo image capturing and manual processing, followed by computer assisted image analysis. We analysed 179 paired images obtained with the contrast-enhanced-phototrichogram method with exogen collection (CE-PTG-EC) in 13 healthy male controls and in 87 men with male pattern hair loss (MPHL). There was a global positive correlation between thickness and growth rate (ANOVA; p<0.0001) and a statistically significantly (ANOVA; p<0.0005) slower growth rate in MPHL as compared with equally thick hairs from controls. Finally, the growth rate recorded in the more severe patterns was significantly (ANOVA; P ≤ 0.001) reduced compared with equally thick hair from less severely affected MPHL or controls subjects. Reduced growth rate, together with thinning and shortening of the anagen phase duration in MPHL might contribute together to the global impression of decreased hair volume on the top of the head. Amongst other structural and functional parameters characterizing hair follicle regression, linear hair growth rate warrants further investigation, as it may be relevant in terms of self-perception of hair coverage, quantitative diagnosis and prognostic factor of the therapeutic response.

Tumor Directed, Scalp Sparing Intensity Modulated Whole Brain Radiotherapy for Brain Metastases.

Despite significant technical advances in radiation delivery, conventional whole brain radiation therapy (WBRT) has not materially changed in the past 50 years. We hypothesized that IMRT can selectively spare uninvolved brain and scalp with the goal of reducing acute and late toxicity. MRI/CT simulation image registration was performed. We performed IMRT planning to simultaneously treat the brain tumor(s) on MRI + 5 mm margin to 37.5 Gy in 15 fractions while limiting the uninvolved brain + 2 mm margin to 30 Gy in 15 fractions and the mean scalp dose to #18 Gy. Three field IMRT plans were compared to conventional WBRT plans. Symptomatic patients were started on conventional WBRT for 2 to 3 fractions while IMRT planning was performed. Seventeen consecutive patients with brain metastases with RPA class I and II disease with no leptomeningeal spread were treated with IMRT WBRT. Compared to conventional WBRT, IMRT reduced the mean scalp dose (26.2 Gy vs. 16.4 Gy, p < 0.001) and the mean PTV30 dose (38.4 Gy vs. 32.0 Gy, p < 0.001) while achieving similar mean PTV37.5 doses (38.3 Gy vs. 38.0 Gy, p = 0.26). Using Olsen hair loss score criteria, 4 of 15 assessable patients preserved at least 50% of hair coverage at 1 to 3 months after treatment while 6 patients preserved between 25 and 50% hair coverage. At a median follow-up of 6.8 months (range: 5 to 15 months), the median overall survival was 5.4 months. Four patients relapsed within the brain, one within the PTV37.5 and three outside the PTV37.5. Tumor directed, scalp sparing IMRT is feasible, achieves rational dose distributions and preserves partial hair coverage in the majority of patients. Further studies are warranted to determine whether the increased utilization of resources needed for IMRT are appropriate in this setting.

Comparative hair restorer efficacy of medicinal herb on nude (Foxn1nu) mice.

Eclipta alba (L.) Hassk, Asiasarum sieboldii (Miq.) F. Maek (Asiasari radix), and Panax ginseng C. A. Mey (red ginseng) are traditionally acclaimed for therapeutic properties of various human ailments. Synergistic effect of each standardized plant extract was investigated for hair growth potential on nude mice, as these mutant mice genetically lack hair due to abnormal keratinization. Dried plant samples were ground and extracted by methanol. Topical application was performed on the back of nude mice daily up to completion of two hair growth generations. The hair density and length of Eclipta alba treated mice were increased significantly (P > 0.001) than control mice. Hair growth area was also distinctly visible in Eclipta alba treated mice. On the other hand, Asiasari radix and Panax ginseng treated mice developing hair loss were recognized from the abortive boundaries of hair coverage. Histomorphometric observation of nude mice skin samples revealed an increase in number of hair follicles (HFs). The presence of follicular keratinocytes was confirmed by BrdU labeling, S-phase cells in HFs. Therefore, Eclipta alba extract and/or phytochemicals strongly displayed incomparability of hair growth promotion activity than others. Thus, the standardized Eclipta alba extract can be used as an effective, alternative, and complementary treatment against hair loss.

Greying of the human hair: a worldwide survey, revisiting the ‘50’ rule of thumb

While numerous papers have reported on the biological mechanisms of human hair pigmentation and greying, epidemiological descriptions of both natural hair colour and the greying process, worldwide, remain scarce. To assess hair colour and greying in a large world sample of human subjects, and to revisit the validity of the 50/50/50 rule of thumb, which states that 'at age 50 years, 50% of the population has at least 50% grey hair'. The natural hair colour of 4192 healthy male and female volunteers was assessed using a sensorial expert evaluation through the comparison of each volunteer's hair with standard swatches. Hair colour was studied according to age, gender and ethnic or geographical origin. Overall we observed that between 45 and 65 years of age, 74% of people were affected by grey hair with a mean intensity of 27%. Men harboured significantly more grey hair than women. Both age at onset and rate of greying with age appeared to be clearly linked to ethnic/geographical origin. Subjects of Asian and African descent showed less grey hair than those of caucasian origin, at comparable ages, confirming previously reported data. Calculating the percentage of people showing at least 50% grey hair coverage at age 50 years leads to a global range of 6-23%, according to ethnic/geographical origin and natural hair colour: well below that expressed by the '50' rule of thumb.

Tactile and thermal detection thresholds of the scalp skin

The tactile and thermal sensitivity of diverse regions of the human body have been documented extensively, with one exception being the scalp. Additionally, sensory changes may accompany the hair loss from the scalp in androgen-related alopecia (ARA), but formal quantitative sensory testing (QST) has not been reported in respect of this. Therefore, light touch detection thresholds were obtained at nine scalp sites and one forehead site, using Semmes–Weinstein filaments (Von Frey hairs), and for warming and cooling from skin baseline temperature, using 28 and 256 mm2 thermodes. Affective, thermal, and nociceptive sensations experienced at thermal detection threshold were quantified. Thirty-two male participants were recruited, 10 of whom had normal hair coverage, 12 of whom had shaved scalp but with potentially normal hair coverage, and 10 of whom exhibited ARA to some extent. The scalp was relatively insensitive to tactile and thermal stimulation at all tested sites, especially so along the midline and near the apex of the skull. Threshold level warm stimuli were rated less pleasant, the less sensitive the test site. After correction for age-related changes in sensitivity, bald scalp sites were found more sensitive to cooling than the same sites when shaved, consistent with prior informal reports of increased sensitivity for some scalp sensations in ARA. QST on hair-covered sites was subject to methodological issues that render such testing non-ideal, such as bias in measurement of resting skin temperatures, and the near impossibility of delivering filament stimuli to the scalp skin without disturbing neighboring hairs.

An easy, low-cost method for achieving adequate facial hair coverage for surgeons

An easy, low-cost method for achieving adequate facial hair coverage for surgeons

An easy, low-cost method for achieving adequate facial hair coverage for surgeons

An easy, low-cost method for achieving adequate facial hair coverage for surgeons

An easy low-cost method for achieving adequate facial hair coverage for surgeons

An easy low-cost method for achieving adequate facial hair coverage for surgeons

Vitamin D3 synthesis in the entire skin surface of dairy cows despite hair coverage

How hair-coated animals such as dairy cows synthesize endogenous vitamin D3 during exposure to summer sunlight has been unclear since vitamin D3 and its relation to sunlight was discovered. The fur of fur-bearing animals is thought to be comparable to clothing in humans, which prevents vitamin D3 synthesis in the skin during exposure to sunlight. Different scenarios have been suggested but never tested in cows; for example, that vitamin D3 is synthesized from sebum on the hair and ingested by cows during grooming or that body areas such as the udder and muzzle that have scant hair exclusively produce the vitamin. To test different scenarios, 16 Danish Holstein dairy cows were subjected to 4 degrees of coverage of their bodies with fabric that prevented vitamin D3 synthesis in the covered skin areas. The treatments were horse blanket (cows fitted with horse blankets), udder cover (cows fitted with udder covers, horse blanket+udder cover (cows fitted with both horse blankets and udder covers), and natural (cows without any coverage fitted). The cows were let out to pasture daily between 1000 and 1500h for 4 wk in July and August 2009. Blood samples were collected 15 times during the study and analyzed for content of 25-hydroxyvitamin D3 [25(OH)D3] indicative of the animals’ vitamin D3 status. Results showed that uncovered cows had a higher 25(OH)D3 concentration in plasma after 28 d of access to sunlight compared with covered cows and that the plasma concentration of 25(OH)D3 was strongly inversely correlated to the body surface area covered. These results are consistent with findings in humans, wherein the vitamin D3 status of different individuals was inversely proportional to the amount of clothing worn during exposure to artificial sunlight. Hence, it appears that human clothing and cow hair are not comparable with respect to prevention of vitamin D3 synthesis and that cows, like humans, synthesize vitamin D3 evenly over their body surface. That vitamin D3 should be synthesized from sebum on the hair and obtained by cows as a result of grooming is not supported by the findings in the present study either, because large differences were found between the treatment groups. If grooming were the source of vitamin D3, then a relatively even 25(OH)D3 concentration between treatments would be expected, because covered cows would obtain vitamin D3 by grooming uncovered herdmates.

Hypothesis: hair cover can protect against invasive melanoma on the head and neck (Australia).

The anatomic distribution of cutaneous melanoma reflects people’s levels and patterns of sun exposure. While examining trends of incident invasive melanomas by site in recent decades in Australia we noted significant increases in incidence on the ears but not the face or any other site in women younger than 40 years, by 6% (95% confidence interval [CI] 2–10%) per year, and 40–59 years by 7% (95% CI 4–10%) per year. Men of the same age showed no corresponding changes in ear melanoma. However incidence rates of ear melanoma in general were fourfold higher in males than females in Australia. Further, using data from the National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) Program, rates of invasive melanoma on the ear were found to be sevenfold higher in males than females in the US population in the same period. Higher rates of scalp and neck melanomas were also seen in men and women in both populations. We therefore speculated that the isolated rises of ear melanoma in younger women in Australia, and the higher overall rates of ear, scalp and neck melanoma in men compared with women, reflect differences in hair coverage. We tested the specific hypothesis that hair cover reduces sun exposure of the ears using experimental manikins and found that hair cover of the ear reduced solar ultraviolet-B exposure by 81% [SE ±8] compared with uncovered ears. We conclude that hair cover can protect against invasive melanoma on the ear and may similarly protect on the scalp and neck. When discretionary, hair may be an important additional factor to be considered for melanoma prevention.

Clinical comparison of four hair removal lasers and light sources

Background and objective: There are few clinical studies directly comparing the efficacy of multiple hair removal systems in the same individual. This study evaluates the efficacy of four highly popular systems for laser hair removal. Methods: In this prospective comparison study, 10 subjects underwent treatment of unwanted hair on the back or thigh. Subjects were skin types I–III, aged 18–55 years. All were treated twice with (1) an intense pulsed light with a red filter; (2) an intense pulsed light with a yellow filter; (3) an 810 nm diode laser; and (4) a 755 nm alexandrite laser. Four treatment areas, using commonly accepted parameters for permanent hair reduction, as well as a control non‐treated area were selected. Each treatment area was evaluated with a camera system specifically designed for hair counts at 1, 3, and 6 months after the second treatment by a blinded non‐treating physician. Clinical results and adverse events were also noted. Results: Evaluation of photographs at 1, 3, and 6 months revealed a significant decrease in hair counts (∼50%) and hair coverage (∼55%). In the hairs that remained after two treatments, no statistical difference was noted in hair length or diameter. There was no statistical difference in efficacy between the four different light devices. Minimal transient adverse effects were noted from all systems. The cryogen spray‐based alexandrite laser showed the highest pain scores. Conclusion: Although hair removal with commonly used systems is, as expected, highly effective, treatment with light‐based devices can cause less pain, yet show efficacy similar to laser systems.

Genetic parameters in Finnish blue fox population: Pelt character and live animal grading traits

Finnish blue fox farmers breed for increased litter size and pelt size, and improved fur quality. Some farmers select pelt size and fur quality indirectly using live animal evaluations (grading traits). In order to be able to define breeding goals properly, heritabilities and genetic correlations were estimated for size traits and fur quality traits. There were four pelt character traits (pelt size, pelt colour darkness, pelt colour clarity and pelt quality) measured on dried skins, and six grading traits (animal size, grading colour darkness, grading colour clarity, underfur density, guard hair coverage and grading quality). The data included 54,680 animals born during the years 1987–2002, originating from seven farms. The heritabilities were high for pelt colour darkness and grading colour darkness, moderate for pelt size and low for other traits. In general, heritability of a pelt character trait was higher than its corresponding grading trait. Genetic correlations within the pelt character traits were low (∼0.11) and within the grading traits mainly moderate or high (∼0.44). There was high genetic correlation between pelt darkness and grading darkness, pelt quality and grading density, pelt size and animal size; between pelt quality and grading quality and between pelt colour darkness and grading guard hair coverage. This suggests that selection of pelt character traits via grading traits in most cases is relatively effective.

Male androgenetic alopecia

Male pattern hair loss is the most common cause of balding. The pathogenesis involves androgen, and in particular dihydrotestosterone, binding to androgen receptors in the dermal papilla of sensitive hair follicles. Hair follicle sensitivity is genetically determined and shows regional specificity. Androgen stimulation of scalp dermal papilla cells induces transforming growth factor beta (TGF-B) and results in cyclical miniaturization of the entire hair follicle. The resulting hair produced from that follicle is shorter and finer and provides less complete scalp coverage. In contrast androgen stimulation of beard dermal papilla cells produces insulin growth factor -2 (IGF-2) and results in cyclical enlargement of the entire hair follicle. The resulting hair produced from that follicle is longer and thicker and provides more complete facial skin coverage. Some degree of androgenetic alopecia is universal among ageing men, especially bitemporally, however less than half become bald in the Hippocratic sense. Although scalp hair coverage has little functional importance, it has cosmetic significance. Baldness changes the facial appearance of affected men. When that change is perceived as adverse it has the potential to produce emotional morbidity.

Restoration of hair growth in mice with an alopecia areata-like disease using topical anthralin.

Anthralin is a widely used topical anti-psoriatic drug that may have an immunomodulating effect on alopecia areata (AA) as it does in psoriasis. The aims of the present study were to investigate the effects of anthralin on hair growth in balding C3H/HeJ mice affected by an AA-like disease and to study the underlying mechanisms. Affected C3H/HeJ mice were treated daily for 10 weeks on half of the dorsal skin with 0.2% anthralin and the contra-lateral side was treated with the vehicle ointment. The percentage of surface hair coverage and hair density was graded weekly for both sides and hair growth indices were calculated using these two variables. Hair regrowth was observed in 9/14 mice on the treated sides. Four mice displayed near complete replacement of normal density and length hairs. All the vehicle-treated sides showed either no change or continued hair loss. An RNase protection assay (RPA) showed that expression of tumor necrosis factor-alpha (TNF-alpha) and -beta were inhibited by anthralin upon successful treatment. It appears that anthralin may be an effective therapy for C3H/HeJ mice with AA and certain cytokines may be involved in the therapeutic effects of anthralin on restoring hair regrowth in AA-affected C3H/HeJ mice.

Histopathologycal and topical immunologycal changes in alopeciae

Male pattern hair loss is the most common cause of balding. The pathogenesis involves androgen, and in particular dihydrotestosterone, binding to androgen receptors in the dermal papilla of sensitive hair follicles. Hair follicle sensitivity is genetically determined and shows regional specificity. Androgen stimulation of scalp dermal papilla cells induces transforming growth factor beta (TGF-B) and results in cyclical miniaturization of the entire hair follicle. The resulting hair produced from that follicle is shorter and finer and provides less complete scalp coverage. In contrast androgen stimulation of beard dermal papilla cells produces insulin growth factor -2 (IGF-2) and results in cyclical enlargement of the entire hair follicle. The resulting hair produced from that follicle is longer and thicker and provides more complete facial skin coverage. Some degree of androgenetic alopecia is universal among ageing men, especially bitemporally, however less than half become bald in the Hippocratic sense. Although scalp hair coverage has little functional importance, it has cosmetic significance. Baldness changes the facial appearance of affected men. When that change is perceived as adverse it has the potential to produce emotional morbidity.

Hair Transplantation Update

Since the first published description in 1959, hair transplantation has progressed tremendously. This article provides an overview of hair transplantation and a discussion of selected controversies in hair transplantation. A review of the literature was undertaken to identify current controversies. Hair transplantation has been refined considerably since it was first performed. As new methods are described, controversies arise. In hair transplantation, these include use of various forms of anaesthesia, the planning of the recipient site, method of harvesting the donor area, megatransplant sessions, isolated frontal forelock transplantation, and use of lasers in hair transplantation. Hair transplantation is a time-tested, highly effective, permanent and natural method of improving male-pattern baldness and female alopecia. Improvements in technique continue to be developed, requiring one to keep abreast of changes in the field in order to provide patients with the best hair coverage possible while maintaining a natural appearance.

25—CROSS-BREEDING STUDIES WITH SELECTED FLEECE LINES OF SCOTTISH BLACKFACE SHEEP

This paper presents the results of an investigation of the fleeces of sheep that were the offspring of crosses (HF) between a hairy line (HH) of the Scottish Blackface breed that had been selected for 20 years for hairiness and a fine line (FF) that had been selected for fine fleeces. Other crosses investigated were between each of the selected lines and an unselected Control (CC) line (HC and FC), and with the Wensleydale breed (WH and WF). The lines had been selectively bred on an index of wool-fibre medullation determined from an eight-week-lamb coat sample, and there was some evidence of heterosis in the index of HC lambs, the values being closer to the value in hairy lambs than the mid-parent value. Fibre-type array (FTA) determined at the same age showed that HC and HF animals were more hairy than Controls, while FC lambs had finer arrays. The Wensleydale-cross lambs had considerably reduced hair coverage and lower hair densities than the Blackface, and FTAs showed a shift from the 100% Plateau arra...