Hair Width Research Articles

Comparative analysis of low-dose oral minoxidil with spironolactone versus finasteride or dutasteride in female androgenetic alopecia management.

LDOM has enhanced treatment options for female AGA, yet its combined efficacy with therapies such as spironolactone, finasteride, or dutasteride remains inadequately explored. This study aims to compare the efficacy and safety of LDOM in combination with spironolactone versus LDOM with finasteride or dutasteride in women with AGA. Our analysis revealed that both combination therapies produced similar improvements in hair growth and had comparable safety profiles. Although the LDOM with finasteride/dutasteride group showed a greater average increase in hair width and density, these differences were not statistically significant. These results endorse the use of LDOM in combination with either spironolactone or finasteride/dutasteride for female AGA, and underscore the necessity for further research to validate these findings and assess long-term treatment outcomes.

The effect of a helmet type, home-use low-level light therapy device for chemotherapy-induced alopecia: study protocol for a randomized controlled trial

BackgroundAlopecia is one of the most common adverse effects of chemotherapy. It reduces the patient’s self-esteem and quality of life and the effect of therapy. Scalp cooling is the only verified current method for prevention but success is not guaranteed, particularly after receiving anthracycline-based combinations.Low-level light therapy has been clinically proven to inhibit the progress of androgenic alopecia. A previous study using human subjects shows limited benefits for low-level light therapy for patients who suffer chemotherapy-induced alopecia but an increase in the number of probes and the optimization of light sources may improve the efficacy. This study determines the efficacy of low-level light therapy for the prevention of chemotherapy-induced hair loss for patients with breast cancer using a randomized controlled trial.MethodsOne hundred six eligible breast cancer patients were randomly distributed into a low-level light therapy group and a control group, after receiving chemotherapy. Subjects in the low-level light therapy group received 12 courses of intervention within 4 weeks. Subjects in the control group received no intervention but were closely monitored.The primary outcome is measured as the difference in the hair count in a target area between the baseline and at the end of week 4, as measured using a phototrichogram (Sentra scalp analyzer). The secondary outcomes include the change in hair count at the end of week 1, week 2, and week 3 and hair width at the end of week 1, week 2, week 3, and week 4, as measured using a phototrichogram, and the change in distress, the quality of life, and self-esteem due to chemotherapy-induced alopecia, at the end of week 4, as measured using a questionnaire.DiscussionThis study improves cancer patients’ quality of life and provides clinical evidence.Trial registrationRegistered at ClinicalTrials.gov—NCT05397457 on 1 June 2022.

Efficacy of paxman scalp cooling system at lower temperatures for prevention of anthracycline associated chemotherapy induced alopecia.

12108 Background: Chemotherapy induced alopecia (CIA) significantly impairs QoL. Scalp cooling devices typically used at -5°C decrease CIA. However, there is still room to improve efficacy with anthracycline therapy. This prospective study was performed to evaluate the safety, tolerability, and efficacy of the Paxman Scalp Cooling System (PSCS)® when used at cooler temperatures of -7.5°C and -10°C. Methods: Patients with stage I-III breast cancer receiving anthracycline chemotherapy at Memorial Sloan Kettering Cancer Center from 12/23/2019 – 10/12/2022 were enrolled on this IRB-approved study. They were evaluated for hair loss at baseline, weeks 4, 8 (primary endpoint), end of treatment, and 24 weeks post treatment using clinical photography and trichoscopy, which measures hair width and count. Degree of hair loss was graded using the Common Terminology Criteria for Adverse Events (CTCAE) v4. Successful hair preservation is indicated by alopecia grades 0 and 1. Results: 34 patients (mean age 44) used the PSCS at cooler temperatures with no DLTs. 7 patients received scalp cooling at -7.5°C and 27 patients at -10°C. 19 women (55.9%) were included in the final analysis; 7 patients withdrew or were taken off study prior to the primary endpoint and 8 patients did not successfully complete photographic or trichoscopic follow-up assessments. At the baseline visit, 95% of patients had grade 0 alopecia (n = 18) and 5.3% had grade 1 alopecia (n = 1). At week 8 (primary endpoint) 53% of patients had grade 1 alopecia and 47% had grade 2 alopecia. At completion of therapy, 7% of patients had grade 0 alopecia, 36% had grade 1 alopecia, 7% are pending and 50% had grade 2 alopecia. At 24 weeks post treatment completion, 23% of patients had grade 0 alopecia (n = 3), 31% had grade 1 alopecia (n = 4), and 46% of patients are pending results (n = 6). At baseline, the average hair count was 149.0 per cm2 (n = 19) and the average hair width was 68.9μm (n = 19). At week 4 and 8, there was a -27% and -8.9% change in hair count and -8.6% and -9.3 percent change in hair width (n = 18) respectively. By end of treatment, percent change was -37.8 and -11.6 for hair count and hair width, respectively (n = 14). At 24 weeks post treatment completion, both the average hair count and hair width for patients were higher compared to their baseline (hair count = 242 per cm2 and hair width = 70.7μm (n = 13; 6 patients pending). Conclusions: Overall, use of the PSCS for successful hair preservation is effective, safe, and tolerable at lower temperatures for patients being treated with anthracycline chemotherapy. 43% of patients had hair preservation at the completion of the study. At 24 weeks post treatment, the average hair count and width was higher than the values at baseline indicating thicker, full hair regrowth. None of the patients displayed grade 2 alopecia at 24 weeks post treatment, allowing patients to avoid the use of a wig to hide resulting CIA. Clinical trial information: NCT04180579 .

“Time Meant Nothing”: A New Reading of Pietro di Donato's Three Circles of Light beyond Autobiography and Stereotypes

“Time Meant Nothing”: A New Reading of Pietro di Donato's <i>Three Circles of Light</i> beyond Autobiography and Stereotypes

Splitting hairs: differentiating juvenile from adult deer (Odocoileus virginianus) by hair width

Abstract Ungulates are a main component in carnivore diets but determining consumption of juveniles is difficult. Past studies have used size of prey remains such as small hooves or bones to classify scat samples as containing content attributable to juveniles. Hair thickness and color may also be used, but seasonality could influence the coat of an adult by developing thinner hairs in summer that more closely resemble those from juveniles. Given this uncertainty, we aimed to quantitatively determine a hair diameter threshold to categorize the age-class of ungulate hair in scats. We obtained hair samples from captive (n = 133) and vehicle-killed (n = 5) white-tailed deer (Odocoileus virginianus) from Georgia and Virginia. We used microphotography image analysis to measure the width of hairs and their cuticular casts. We used a linear model to assess differences among body locations, age-classes, and locations along the hair strand. We also analyzed the change in hair width of juveniles as they aged. Hair diameter of adults, but not juveniles, differed significantly depending on body location, yet adult hairs were always significantly wider than those from juveniles. Juvenile hairs significantly increased in width after mid-September, when they molt into adult coats in our study area. We identified 104.2 µm measured at either 1/8 or 1/4 distance from the follicle as a threshold width to distinguish adult from juvenile hairs, with 95.3% accuracy. Our findings indicate that juvenile white-tailed deer can be distinguished from adults based on the width of hairs found in carnivore scats up until juveniles are 5 months old. More broadly, our results demonstrate that hair width may be used to classify juvenile versus adult prey remains in carnivore diet studies in other predator–prey systems.

AIRE Deficiency Leads to the Development of Alopecia Areata‒Like Lesions in Mice

Alopecia areata (AA) is an autoimmune hair loss disorder with no cure. Patients with sequence variation in AIRE are 15 times more likely to develop AA than the general population, yet the roles of AIRE in AA pathogenesis are unknown. In this study, we report that 62% of C57BL/6J female Aire‒/‒ mice spontaneously developed persistent AA-like lesions that displayed several hallmarks of human AA. Lesional Aire‒/‒ skin exhibited hair follicle (HF) dystrophy as determined by a reduced number of anagen HFs, decreased anagen HF proliferation, hair pigmentary changes, and decreased hair width and length. Inflammatory infiltrate comprising CD8+ T cells, CD4+ T cells, CD68+ macrophages, and mast cells was prominent in lesional Aire‒/‒ HFs. From gene expression analyses, we found lesional Aire‒/‒ skin to have significantly increased expression of human AA signature genes, including H2-Ab1, Ifnγ, IFN-γ‒induced chemokines (Ccl5, Cxcl9‒11), γc family cytokine receptor Il2RA, and JAK‒signal transducer and activator of transcription (STAT) signaling components (Stat1, Stat2, Stat4). By immunostaining, lesional Aire‒/‒ HFs also show upregulated major histocompatibility complex class I and downregulated α-melanocyte-stimulating hormone, signifying immune privilege collapse, and increased STAT1 activation in HF keratinocytes. Our study highlights a role for AIRE in HF biology and shows that Aire‒/‒ mice may serve as a valuable model system to study AA pathogenesis.

708 Aire deficiency induces upregulation of JAK-STAT signaling in keratinocytes and results in alopecia areata-like lesions in mice

Alopecia areata (AA) is an autoimmune hair loss disorder with no cure. We report here that C57BL/6J female mice with germline deficiency in autoimmune regulator (Aire-/-) spontaneously developed AA-like lesions (n=61/98; 62%). Aire-/- lesions exhibited AA hallmarks such as miniaturized hair follicles (HFs), decreased hair width (-29%, p<0.0173) and length (-27%, p=0.0002), and increased lymphocytic infiltrate at the hair bulb (+191% in CD8+ T cells, p=0.0546) relative to body site matched Aire+/+ tissue.

Interaction of OsRopGEF3 Protein With OsRac3 to Regulate Root Hair Elongation and Reactive Oxygen Species Formation in Rice (Oryza sativa).

Root hairs are tip-growing cells that emerge from the root epidermis and play a role in water and nutrient uptake. One of the key signaling steps for polar cell elongation is the formation of Rho-GTP by accelerating the intrinsic exchange activity of the Rho-of-plant (ROP) or the Rac GTPase protein; this step is activated through the interaction with the plant Rho guanine nucleotide exchange factor (RopGEFs). The molecular players involved in root hair growth in rice are largely unknown. Here, we performed the functional analysis of OsRopGEF3, which is highly expressed in the root hair tissues among the OsRopGEF family genes in rice. To reveal the role of OsRopGEF3, we analyzed the phenotype of loss-of-function mutants of OsRopGEF3, which were generated using the CRISPR-Cas9 system. The mutants had reduced root hair length and increased root hair width. In addition, we confirmed that reactive oxygen species (ROS) were highly reduced in the root hairs of the osropgef3 mutant. The pairwise yeast two-hybrid experiments between OsRopGEF3 and OsROP/Rac proteins in rice revealed that the OsRopGEF3 protein interacts with OsRac3. This interaction and colocalization at the same subcellular organelles were again verified in tobacco leaf cells and rice root protoplasts via bimolecular functional complementation (BiFC) assay. Furthermore, among the three respiratory burst oxidase homolog (OsRBOH) genes that are highly expressed in rice root hair cells, we found that OsRBOH5 can interact with OsRac3. Our results demonstrate an interaction network model wherein OsRopGEF3 converts the GDP of OsRac3 into GTP, and OsRac3-GTP then interacts with the N-terminal of OsRBOH5 to produce ROS, thereby suggesting OsRopGEF3 as a key regulating factor in rice root hair growth.

Hairs of wild Felis silvestris silvestris and domestic Felis catus – are they distinctive after all? (Carnivora: Felidae)

This study addressed the question whether it is possible to clearly differentiate between wild and tabby domestic cats on the basis of hairs (guard hairs in particular). The colour banding pattern of individual hairs is studied in this context for the first time. Also, hair length and width, as well as parameters of the hair cuticle were checked for differences, as it is well known that wild cats have long hairs and a fine, silky fur. Several banding patterns were observed, some shared between both cat forms, but with different frequencies. But this is not enough for species differentiation and more specimens need to be studied to get a better idea of the variation in this trait. The cuticle pattern even in the same region of the hairs (medium and shield-free part of the hair shaft) varies considerably and statistically significant differences were found only for few measured parameters: hair length, hair width and scale perimeter. Nevertheless, even most of them are not sufficient to determine wild or domestic cats. However, as expected, the hairs of wild cats are statistically significantly longer than those of tabby domestic cats, and hairs longer than 50 mm can be clearly attributed to wild cats.

Preliminary study on morphometric analysis of the human scalp hair for discrimination of ethnic Malay and ethnic Chinese in Malaysia

BackgroundHair is one of the most frequently encountered trace evidence in crime scenes. It has been used for differentiating races or identifying species of animals. An understanding of intra- and inter-variation of human scalp hair may enable discrimination based on ethnicity. This study aims to discriminate the ethnic Malays and ethnic Chinese in Malaysia based on three morphometric measurements of the human scalp hair.MethodThe sample group was composed of 100 Malaysians, 50 each (i.e. 25 males and 25 females) from ethnic Malays and ethnic Chinese. Each subject has provided 20 strands of hair. The hair width (HW), scale layer difference (SLD), and medullary index (MI) of each hair were determined using a compound microscope. Following that, the inter-variation of hair was evaluated according to (a) head regions, (b) sex, and (c) ethnic groups and assessed using descriptive and inferential statistics, i.e. independent t test and Wilcoxon’s rank-sum test.ResultsResults show that Malays and Chinese are different in all the three morphometries. However, Malay males are different from females only in terms of SLD, and Chinese males and females could be discriminated using MI. Next, hair originating from upper and lower head regions, regardless of ethnicity and sex, are not significantly different.ConclusionIn conclusion, Malays and Chinese could be discriminated based on morphometric measurements of scalp hair. The finding sheds new light on the feasibility of differentiating ethnic groups using physical measurements alone.

Linking root traits to superior phosphorus uptake and utilisation efficiency in three Fabales in the Core Cape Subregion, South Africa.

In the low-P soil of the fynbos biome, plants have evolved several morphological and physiological P acquisition and use mechanisms, leading to variable uptake and use efficiencies. We expected that plants grown in low-P soils would exhibit greater P acquisition traits and hypothesised that Aspalathus linearis (Burm. f.) R. Dahlgren, a cluster-root-forming species adapted to drier and infertile soils, would be the most efficient at P acquisition compared with other species. Three fynbos Fabales species were studied: A. linearis and Podalyria calyptrata (Retz.) Willd, both legumes, and Polygala myrtifolia L., a nonlegume. A potted experiment was conducted where the species were grown in two soil types with high P (41.18mgkg-1) and low P (9.79mgkg-1). At harvest, biomass accumulation, foliar nutrients and P acquisition mechanisms were assessed. Polygala myrtifolia developed a root system with greater specific root length, root hair width and an average root diameter that exuded a greater amount of citrate and, contrary to the hypothesis, exhibited greater whole-plant P uptake efficiency. However, P. calyptrata had higher P use efficiency, influenced by N availability through N2 fixation. Specific root length, root length and root:shoot ratio were promising morphological traits for efficient foraging of P, whereas acid phosphatase exudation was the best physiological trait for solubilisation of P.

890 Impact of a stimulating cream shampoo treatment on the penetration of minoxidil through hair follicles

Androgenetic alopecia (AGA) presents clinically with reduced hair density and hair width due to shortening of the hair cycle in genetically predisposed scalp areas. The effectiveness of Minoxidil in AGA has been demonstrated in numerous randomized controlled trials. However, there is a need to enhance its bioavailability in hair follicles. Our laboratory developed a stimulating cream shampoo that prepares the scalp to reactivate its vital functions and those of the hair. This shampoo can be used before application of Minoxidil in order to help the penetration of Minoxidil. The aim of this study was to investigate this hypothesis evaluating the difference of Minoxidil penetration through hair follicles following topical application with and without pre-treatment with the stimulating cream shampoo. The skin penetration study was realized at finite conditions (10μl/cm2) on human scalp. The scalp was mounted on dynamic cells using radiolabelled compounds (3H-Minoxidil). 3H-Minoxidil was quantified in the different compartments of the skin (surface, SC, hair follicles, skin and receptor fluid) by scintillation counting. The mass balance was in accordance with guidelines (100 ± 15%) and permits to validate the study. After 10 min, significant higher quantities of Minoxidil were recovered into the hair follicles and scalp after pre-treatment with the stimulating cream shampoo. Indeed, the quantity of Minoxidil recovered into the hair follicles was 1.41 μg and 0.29μg, with and without shampoo pretreatment. In the scalp, Minoxidil quantity reached 32.02 μg and 6.62μg, with and without shampoo, respectively. The data obtained permits to conclude on the enhancing effect of the stimulating cream shampoo on Minoxidil penetration and help to target the hair follicles.

Effect of minoxidil topical foam on frontotemporal and vertex androgenetic alopecia in men: a 104-week open-label clinical trial.

Topical minoxidil formulations have been shown to be effective in treating androgenetic alopecia (AGA) for 12months. Efficacy and safety in both frontotemporal and vertex regions over longer application periods have not been studied so far. To evaluate the effect of 5% minoxidil topical foam (5% MTF) in the frontotemporal and vertex areas in patients with moderate AGA over 104weeks. An 80-week, open-label extension phase was performed, following a 24-week randomized, double-blind, placebo-controlled study in men with AGA grade IIIvertex to VI. Group 1 (n=22) received ongoing 5% MTF for 104weeks, Group 2 (n=23) received placebo topical foam (plaTF) until week 24, followed by 5% MTF until week 104 during the extension phase. Frontotemporal and vertex target area non-vellus hair counts (f-TAHC, v-TAHC) and cumulative hair width (f-TAHW, v-TAHW) were assessed at baseline and at weeks 24, 52, 76 and 104. In Group 1, f-TAHW and f-TAHC showed a statistically significant increase from baseline to week 52 and week 76, respectively, returning to values comparable to baseline at week 104. No significant differences were found between baseline and week 104 in v-TAHC in Group 1 as well as f-TAHC, v-TAHC, f-TAHW and v-TAHW values in Group 2. 5% MTF is effective in stabilizing hair density, hair width and scalp coverage in both frontotemporal and vertex areas over an application period of 104weeks, while showing a good safety and tolerability profile with a low rate of irritant contact dermatitis.

A Single-Centre, Randomized, Double-Blind, Placebo-Controlled Clinical Trial to Investigate the Efficacy and Safety of Minoxidil Topical Foam in Frontotemporal and Vertex Androgenetic Alopecia in Men

Background: 5% minoxidil formulations twice daily are effective in treating vertex male androgenetic alopecia (AGA); however, efficacy and safety data in frontotemporal regions are lacking. Objectives: To assess the efficacy of 5% minoxidil topical foam (5% MTF) in the frontotemporal region of male AGA patients after 24 weeks of treatment compared to placebo treatment and to the vertex region. Methods: Seventy males with moderate AGA applied 5% MTF or placebo foam (plaTF) twice daily for 24 weeks in frontotemporal and vertex regions. Target area non-vellus hair count (TAHC) was the primary end point. Results: Frontotemporal and vertex TAHC and target area cumulative non-vellus hair width (TAHW) showed similar responses to 5% MTF with significant increases up to week 16 compared to baseline (p < 0.001). After 24 weeks of treatment, frontotemporal TAHW increased significantly in the 5% MTF group compared to the plaTF group (p = 0.017), while TAHC showed a similar non-significant increase from baseline in both regions. At 24 weeks, 5% MTF users rated a significant improvement in scalp coverage for the frontotemporal (p = 0.016) and vertex areas (p = 0.027). Conclusions: 5% MTF twice a day promotes hair density and width in both frontotemporal and vertex regions in men with moderate stages of AGA.

A New Era of 5α-Reductase Inhibitors for Androgenetic Alopecia

In addition to these therapies, a new oral drug dutasteride has been reported to be efficient for AGA in a large-scale (n=917) randomized controlled trial (RCT) [2]. This reagent is a 5α-reductase inhibitor similarly to finasteride. Importantly, dutasteride suppresses both type I and II 5α-reductases while finasteride significantly suppresses only type II. Therefore, dutasteride is referred as a “dual inhibitor”. In the RCT the effect for hair growth in AGA was compared between 0.5mg/day dutasteride and 1mg/day finasteride. As a result, dutasteride significantly increased hair count and width and hair photographic assessment compared with finasteride [2]. Additionally, dutasteride improved the global photography in Korean men with AGA recalcitrant to finasteride [3]. On the other hand, a meta-analysis study indicated no significant difference in efficacy for AGA between these two drugs [4]. Collectively, it is still controversial whether there is significant difference in clinical efficiency by dutasteride and finasteride.

Characteristics of nonbalding scalp zones of androgenetic alopecia in East Asians.

Hair is known to persist on the occipital and part of the temporal scalp in patients with androgenetic alopecia (AGA), but no quantified data about the follicular changes in such areas exist. To evaluate the hair characteristics in nonbalding scalp areas in East Asian patients with AGA. In total, 265 participants [211 patients with AGA and 50 healthy controls (HCs)] were enrolled. The patients were divided by the Basic and Specific (BASP) classification [four basic types (L, M, C, and U) and two special types (V and F)], and the hair in the occipital region and two sites of the temporal region were analysed by computer-assisted phototrichography. Hair density, hair width, number of each follicular unit, ratio of single to compound hairs and ratio of terminal to vellus hairs were examined. In the temporal region, a statistically significant (P<0.05) decrease in hair density was observed in patients with C, U or F subtypes, and a significant (P<0.05) decrease in hair thickness was observed in patients with the U subtype compared with HCs. In the mastoid and occipital areas, both hair density and hair thickness was significantly (P<0.05) decreased in patients with the U subtype compared with HCs. Within each classification, hairs became generally thinner as the hair loss progressed. Hair density and hair thickness of known nonbalding scalp regions showed some differences depending on the severity and the BASP subtypes in East Asian people with male pattern baldness.

Photons on Demand

Optik & PhotonikVolume 8, Issue 4 p. 20-20 Research & TechnologyFree Access Photons on Demand Extremely compact optical chips, a hair's width in size, delivering one photon at a time First published: 09 December 2013 https://doi.org/10.1002/opph.201390077AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume8, Issue4December 2013Pages 20-20 ReferencesRelatedInformation

The Transplanted Hairline

The large caliber of head hair in hair transplantation imparts a coarse hairline, whereas natural hairlines are typically softer. In hirsute individuals, transplantation of leg hair to the hairline may result in a superior aesthetic appearance. A total of 1025 leg hair follicles in 1 patient were grafted to an area 0.5 to 1.0 cm in front of and 0.5 to 1.0 cm internal to the vanguard hair of the original hairline and temporal recesses; the other patient received approximately 1000 leg hairs and 600 head hairs to advance and soften his hairline and to create a custom widow's peak. Transplantation resulted in a fully grown and soft-looking hairline after 9 months in the first patient, with growth of 75% to 80% of the transplanted leg hair. The mean length of the transplanted leg hair was longer than the length of the original leg hair, with less curliness but similar hair width. Transplanted leg hair width was significantly finer compared with existing head hair width. After 4 years, results were sustained, minimizing concerns that subsequent hair loss might result from leg hair cycle variations. In the second patient, similar results were observed at 3 years. The use of leg hair in transplantation provides additional options in patients with hairlines that need to be refined.

A randomized, single-blind trial of 5% minoxidil foam once daily versus 2% minoxidil solution twice daily in the treatment of androgenetic alopecia in women

Although twice-daily application of propylene glycol-containing 2% minoxidil topical solution (MTS) stimulates new hair growth, higher concentrations of minoxidil in a once-daily, propylene glycol-free formulation may improve efficacy and reduce unpleasant side effects. We sought to compare the efficacy, safety, and acceptability and to show noninferiority of once-daily 5% minoxidil topical foam (MTF) with twice-daily 2% MTS in women with androgenetic alopecia. A total of 113 women with androgenetic alopecia were randomized to 24 weeks of treatment with 5% MTF or 2% MTS. The primary efficacy parameter was change from baseline in nonvellus target area hair count at week 24. Secondary end points included change in nonvellus target area hair width, overall efficacy by global photographic review as assessed by treatment-blinded evaluators and the subject herself, adverse events, and participants' assessment of product aesthetics. After 24 weeks, women randomized to 5% MTF once daily showed noninferior target area hair count and target area hair width and experienced greater, but nonsignificant, improvements in target area hair count, target area hair width, and overall efficacy by global photographic review than those randomized to 2% MTS used twice daily. 5% MTF was significantly superior to 2% MTS in participants' agreement with "the treatment does not interfere with styling my hair" (P= .002). Women randomized to 5% MTF experienced significantly lower rates of local intolerance (P= .046) especially in pruritus and dandruff compared with 2% MTS. Because of differences in the formulations tested, study participants were not blinded to treatment. Once-daily 5% MTF is noninferior and as effective for stimulating hair growth as twice-daily 2% MTS in women with androgenetic alopecia and is associated with several aesthetic and practical advantages.

Can hair width and scale pattern and direction of dorsal scapular mammalian hair be a relatively simple means to identify species?

Hair width and surface scale patterns (morphological characteristics) of hair from 21 selected species representing seven orders of mammals from the western United States were studied using scanning electron microscopy (SEM). The orders studied were Artiodactyla, Carnivora, Chiroptera, Didelphimorphia, Insectivora, Lagomorpha and Rodentia. Hair width, scale length and height, scale patterns, and scale position in relation to the shaft were used to characterize differences in morphology for both the species and orders. Specimens were taken from the dorsal scapular region and the centres of hair shafts of mature mammals were used for images. A key (identification chart) was created to characterize each species. These studies suggest that morphological differences in guard hair and underfur could provide a useful atlas for forensics, taxonomy and archaeology.