Hairstyling Practices to Prevent Hair Damage and Alopecia in Women of African Descent.

Highly textured hair has been found to be more susceptible to breakage than other hair types due to an increased proportion of spirals and relatively fewer elastic fibers anchoring the hair follicles to the dermis. Women of African descent frequently employ hairstyles and hair treatments for ease of management and as a form of self-expression, but a number of these practices have been implicated as risk factors for alopecia. Herein, we provide an overview of hairstyles for patients with highly textured hair so that physicians may better identify high-risk hairstyles, provide individualized recommendations for safer alternatives, and manage and stop the progression of hair loss before it becomes permanent.

Comparative Graft Survival Study of Follicular Unit Excision Grafts With or Without Minor Injury.

BACKGROUND: Various types of follicular trauma occur during follicular unit excision (FUE). However, the effects of different types of follicular injury on graft survival have not been reported. OBJECTIVE: This study was performed to evaluate the differences in hair follicle survival by the type of follicular injury, including paring, fracture, and bulb injury. METHODS: Seven healthy patients who underwent hair transplant surgery by FUE were enrolled in the study. For each patient, 10 single-hair follicular unit grafts per injury group (paring, fracture, bulb injury, or intact) were differentiated. Using sharp implanters, 10 grafts of each of the 4 injury types were transplanted into mice, and the mice were sacrificed 5 months after transplantation. The skin was excised at each of the 4 locations, and newly formed follicular units were counted and photographed under a microscope. RESULTS: Of 70 hair follicles in each group, the number of successfully engrafted follicles was 50 (71.43%) in the intact group, 36 (51.43%) in the paring injury group, 9 (12.86%) in the fracture injury group, and 31 (44.29%) in the bulb injury group. CONCLUSION: Grafts with minor injury had a lower survival rate than intact grafts. Fractured follicles showed the lowest survival rate.

Effect of surgeon's workload on rate of transection during follicular unit excision/extraction (FUE).

OBJECTIVES: To compare the transection rate at the start and at the end of the FUE procedure. MATERIALS AND METHODS: The study was conducted in a private setup in patients undergoing first session of FUE surgery over 2000 grafts. Six areas of 1 cm2 were marked, two in midline and two on either side. All the procedures were undertaken by the single surgeon to avoid any bias. At the start of the surgery, the extraction of hair was performed in areas A1, A2, and A3. All the excised hair and transected hair were counted. The surgery was then completed but the remaining three areas (B1, B2, and B3) were left intact. Later, FUE was done in these areas. The excised hair and transected hair were counted. All the data were analyzed statistically by paired t test. RESULTS: A total of 25 patients were included in the study. The mean age of the patients was 35.2 years. The transection rate was 5.3/cm2 in mid-zone, 4.4/cm2 on right side, and 5.7/cm2 on left side at the start and 27.7/cm2 in mid-zone, 25.6/cm2 on right side, and 24.2/cm2 on left side at the end. The transection rate increased from 5.03 to 6.0/cm2 for FUS <2500 but increased from 4.83 to 6.6/cm2 with FUs over 2500 and increased from 5.5 to 6.67/cm2 when FUs were over 3000. CONCLUSION: The surgeon's workload increases the hair transection during FUE.

Hairpulling causing vision loss: a case report.

Subperiosteal extension of a subgaleal hematoma (SGH) to the orbit is a reported, but rare complication of trauma. This report details a 13-year-old African-American male who originally presented to the emergency department after trauma with headache and was found on CT imaging to have a contained subgaleal hemorrhage. He presented 2 days later with increased pain and proptosis of the left eye with findings of decreased visual acuity, elevated intraocular pressure, proptosis, and complete external ophthalmoplegia. Repeat imaging revealed enlargement of the SGH with subperiosteal extension into the left orbit. He required an emergent lateral canthotomy with inferior and superior cantholysis, followed by surgical drainage of the subperiosteal and SGH. Hematologic workup for coagulopathy was negative. The authors urge point-of-care providers to consider ophthalmic evaluation for patients with large SGHs where orbital extension and vision loss may occur. Furthermore, SGH causing orbital compartment syndrome may develop in patients who have normal blood work and clotting factors.

Single-Cell Transcriptomics of Traced Epidermal and Hair Follicle Stem Cells Reveals Rapid Adaptations during Wound Healing.

Epithelial tissues, such as the skin, rely on cellular plasticity of stem cells (SCs) from different niches to restore tissue function after injury. How these molecularly and functionally diverse SC populations respond to injury remains elusive. Here, we genetically labeled Lgr5- or Lgr6-expressing cells from the hair follicle bulge and interfollicular epidermis (IFE), respectively, and monitored their individual transcriptional adaptations during wound healing using single-cell transcriptomics. Both Lgr5 and Lgr6 progeny rapidly induced a genetic wound signature that, for Lgr5 progeny, included the remodeling of receptors to permit interactions with the wound environment, a property that Lgr6 progeny possessed even before wounding. When contributing to re-epithelialization, Lgr5 progeny gradually replaced their bulge identity with an IFE identity, and this process started already before Lgr5 progeny left the bulge. Altogether, this study reveals how different SCs respond and adapt to a new environment, potentially explaining cellular plasticity of many epithelial tissues.

Hidden Transection of Follicular Unit Extraction in Donor Site.

BACKGROUND: When calculating the transection rate in follicular unit extraction (FUE), many surgeons did not consider damages that may arise in the donor site through FUE punching. OBJECTIVE: The authors investigated what changes and/or damages are happened to the hair follicles surrounding a punched hole. MATERIALS AND METHODS: Two to 4 study boxes were marked on the donor strip and 8 follicular units were harvested using FUE from each study box. Follicular unit extraction was performed by the expert for 10 patients and by the beginner for 10 patients. After the strip harvesting, each study box was separated. Then, the 2 cross sections along the punched line and follicular units obtained from each study box were analyzed under a 20-power digital microscope. RESULTS: The authors found various transections through this analysis. Among them, some transections were hidden under the scalp surface, keeping the shaft alignment. The authors named this occurrence "hidden transection." Although 2 surgeons harvested with similar transection rate, there was a significant difference in hidden transection rate: 2% for the expert and 8% for the beginner. CONCLUSION: The main finding of this study is that a correct way to calculate the real-transection rate in FUE is to consider both extracted follicular transection and hidden transection.

Is paradoxical hair growth caused by low-level radiant exposure by home-use laser and intense pulsed light devices?

INTRODUCTION AND OBJECTIVES: This qualitative review of paradoxical hair growth, following professional treatments reviews, clarifies whether low fluence is the most probable cause of unwanted hair regrowth after at home light-based treatments. MATERIALS AND METHODS: The proposed causes of unexpected hair regrowth are examined, and our scientific understanding of absorption and scattering of light in turbid tissue is reviewed. Published reports of paradoxical hair growth are assessed. RESULTS: Early laser hair removal studies failed to record the occurrence of hair induction despite the significant numbers of subjects treated. Neither published paradoxical hair growth studies following home-based laser or intense pulsed light (IPL) hair removal treatments, nor randomised or controlled studies documenting paradoxical hair growth following professional treatments could be found. Several authors directly proposed inflammatory response to be the primary cause of hair growth induction. CONCLUSIONS: It is unlikely that hair regrowth several centimetres or more away from the irradiated tissue can be attributed to the laser or IPL used. In many cases of paradoxical hair growth, other causes may be responsible for the unexpected hair growth. The primary cause of instances of 'true' paradoxical hair growth is probably limited to darker phototypes with one or more other characteristics including polycystic ovarian syndrome or other androgen hormonal irregularities following high energy treatments with the corresponding inflammatory sequelae.

Hair follicle and interfollicular epidermal stem cells make varying contributions to wound regeneration.

Upon wounding, multiple stem cell populations in the hair follicle (HF) and interfollicular epidermis (IFE) converge at the site of injury. Although these cells can contribute permanently to the regenerating epithelium, it remains unclear whether these contributions vary among cells originating from diverse compartments in the skin. By comparing the fates of several keratinocyte lineages, we observed here an initial decrease in both HF- and IFE-derived cells within the transient acanthotic layers of the regenerating epithelium. At the same time, the relative abundance of early-arriving IFE-derived cells specifically in the wound basal layer declined as later-arriving HF-derived cells entered the site of injury. Although laggard bulge-derived cells were typically constrained at the regenerative periphery, these cells persisted in the wound basal layer. Finally, suppressing Notch enabled IFE-derived cells to out-compete HF-derived cells. Taken together, these findings indicate that IFE-, HF- and bulge-derived cells make distinct contributions to regeneration over time. Furthermore, we speculate that extrinsic, non-genetic factors such as spatial constraint, distance from the wound, and basal versus suprabasal position may largely determine whether a cell ultimately persists.

Restorative effect of hair follicular dermal cells on injured human hair follicles in a mouse model.

No model is available for examining whether in vivo-damaged human hair follicles (hu-HFs) are rescued by transplanting cultured hu-HF dermal cells (dermal papilla and dermal sheath cells). Such a model might be valuable for examining whether in vivo-damaged hu-HFs such as miniaturized hu-HFs in androgenic alopecia are improvable by auto-transplanting hu-HF dermal cells. In this study, we first developed mice with humanized skin composed of hu-keratinocytes and hu-dermal fibroblasts. Then, a 'humanized scalp model mouse' was generated by transplanting hu-scalp HFs into the humanized skin. To demonstrate the usability of the model, the lower halves of the hu-HFs in the model were amputated in situ, and cultured hu-HF dermal cells were injected around the amputated area. The results demonstrated that the transplanted cells contributed to the restoration of the damaged HFs. This model could be used to explore clinically effective technologies for hair restoration therapy by autologous cell transplantation.

Traction alopecia: how to translate study data for public education--closing the KAP gap?

Traction alopecia (TA) affects up to 32% of women and 22% of high school girls with Afro-textured hair but can start in the preschool years. Traction induces inflammation and follicle damage. The risk of TA increases with symptomatic traction and combined hairstyles. To influence the practice of hairdressers and at risk individuals and help narrow the knowledge, attitudes, and practices (KAP) gap, scientific data should be translated into simple messages like "tolerate pain from a hairstyle and risk hair loss" and "no braids or weaves on relaxed hair". With appropriate education and public awareness, TA could potentially be eradicated.

Optimal graft growth.

Excellent surgical results and high patient satisfaction with hair transplantation depend on attaining optimal growth. Unfortunately, even experienced surgeons acknowledge that graft survival often is not as high as is commonly stated. Hair transplant surgeons should be thoroughly familiar with the many variables that affect graft survival and refine their surgical techniques accordingly. This article provides a brief overview of the key factors that most significantly influence graft survival, including graft trauma, vascular/oxygenation factors, and biochemical injury.

Direct migration of follicular melanocyte stem cells to the epidermis after wounding or UVB irradiation is dependent on Mc1r signaling.

During wound healing, stem cells provide functional mature cells to meet acute demands for tissue regeneration. Simultaneously, the tissue must maintain a pool of stem cells to sustain its future regeneration capability. However, how these requirements are balanced in response to injury is unknown. Here we demonstrate that after wounding or ultraviolet type B irradiation, melanocyte stem cells (McSCs) in the hair follicle exit the stem cell niche before their initial cell division, potentially depleting the pool of these cells. We also found that McSCs migrate to the epidermis in a melanocortin 1 receptor (Mc1r)-dependent manner and differentiate into functional epidermal melanocytes, providing a pigmented protective barrier against ultraviolet irradiation over the damaged skin. These findings provide an example in which stem cell differentiation due to injury takes precedence over stem cell maintenance and show the potential for developing therapies for skin pigmentation disorders by manipulating McSCs.

Hairy tale of signaling in hair follicle development and cycling.

Hair follicles (HFs) is an appendage from the vertebrate skin epithelium, and is critical for environmental sensing, animal appearance, and body heat maintenance. HFs arise from the embryonic ectoderm and regenerate cyclically during adult life. Distinct morphological and functional stages from development through homeostasis have been extensively studied for the past decades to dissect the critical molecular mechanisms. Accumulating work suggests that different signaling cascades, such as Wnt, Bmp, Shh, and Notch, together with specific combinations of transcription factors are at work at different stages. Here we provide a comprehensive review of mouse genetics studies, which include lineage tracing along with knockout and over-expression of core genes from key signaling pathways, to paint an updated view of the molecular regulatory network that govern each stage of hair follicle development and adult cycling.

Histomorphometric analysis and regional variations of full thickness skin grafts in dogs.

OBJECTIVE: To (1) compare thickness of the epidermis and dermis of anatomically different donor sites in dogs, and (2) evaluate hair follicle damage during full thickness skin grafts (FTSG) preparation from anatomically different donor sites. Another objective was to compare the extent of agreement between gross and histologic quality of graft preparation. STUDY DESIGN: Ex vivo study. ANIMALS: Healthy Beagle dogs (n = 12). METHODS: Skin samples were harvested from fresh cadavers free of gross dermatopathology and FTSG prepared. Regional, epidermal and dermal thickness, and hair follicle density in intact skin and FTSG specimens from different regions were determined by histomorphometric analysis. Hair follicle density in intact skin and FTSG specimens, and skin thickness measurements were compared among regions. RESULTS: Mean epidermis and dermis thickness of the dorsal lumbar and lateral neck regions were significantly greater when compared with other sites. Total hair follicle (superficial and deep dermis) densities were significantly less in prepared FTSG versus intact skin specimens. The dorsal lumbar region had the highest hair follicle density. CONCLUSIONS: Thickness of the epidermis and dermis is dependent on body region. Hair follicle density in the FTSG specimens was decreased compared with intact skin specimens, which may affect hair regrowth in FTSG.

The use of polyethylenimine-DNA to topically deliver hTERT to promote hair growth.

The present study investigates the efficacy of polyethylenimine (PEI)-DNA complex that expressed human telomerase reverse transcriptase (hTERT) to transfect hair follicle stem cells and produce sufficient hTERT to stimulate hair growth. Transfection with pLC-hTERT-DNA-PEI complex (D+P group) in vitro induced expression of proliferating cell nuclear antigen in 35.8% of the purified stem cell population, suggesting enhanced cell proliferation. In vivo transfection efficiency of rat dorsal skin was determined by staining for ß-gal activity. Cells positive for ß-gal were located in the bulge region and dermal sheath of hair follicles. The follicles in the hTERT-transfected region entered anagenon day 15 after transfection, whereas non-transfected (Neg) controls remained in telogen. The similar effect was observed in 50-day-old rat dorsal skin. D+P group displayed a specific expression of hTERT and sufficient to initiate a transition to the anagen phase and promote new hair synthesis 18 days after the transfection. hTERT promoted follicle neogenesis following wounding. In all, 60 days after wounding, tissues of the D+P group showed more newly regenerating hair follicles (83±52 regenerated follicles per rat) in contrast to control group tissues (15±15 regenerated follicles per rat). These studies provide a potential approach for gene therapy of skin disease.

Characterization and quantification of wound-induced hair follicle neogenesis using in vivo confocal scanning laser microscopy.

BACKGROUND: In vivo confocal scanning laser microscopy (CSLM) is a recently developed non-invasive technique for visualizing microscopic structures with the skin. CSLM has been used to characterize proliferative and inflammatory skin diseases, neoplastic skin lesions and pigmented lesions. OBJECTIVE: Here, we assessed the ability of CSLM to evaluate the formation of neogenic hair follicles after a full-thickness wound in mice. METHODS: Full-thickness wounds were made on the dorsal skin of 3-week-old mice. After scab detachment (SD), the number, width, length, space and volume of neogenic hair follicles were analyzed using CSLM. The results were compared with those from conventional methods, including staining for alkaline phosphatase (AP) and keratin 17 (K17) as well as histology. RESULTS: Quantification of neogenic hair follicles using CSLM compared favorably with the results from direct measurements on isolated epidermal tissue after immunostaining for K17, a marker for the epithelial portion of new hair follicles. CSLM detected 89% of K17-stained follicles. CSLM more accurately quantified the number of new follicles compared with AP staining, which detects the dermal portion of the new follicle. The width and length measurement from CSLM and histology were very close and correlated with each other. The minimum length of a neogenic hair follicle that could be detected by CSLM was 21 µm. The space between neogenic hair follicles was decreased in histological sections compared with CSLM. CONCLUSION: CSLM is an accurate and valuable method for counting and measuring neogenic hair follicles non-invasively. CSLM produces images similar to histology in mice. Measurements of microstructures using CSLM more accurately reflect actual sizes as this technique avoids fixation artifacts. In vivo visualization of developing follicles with CSLM allows the detection of serial changes in hair follicle formation, thus conserving the numbers of mice required for studies and improving the detection of temporal changes in developing hair follicles.

Traction alopecia in two adolescent Sikh brothers-an underrecognized problem unmasked by migration.

Traction alopecia denotes an often permanent hair loss resulting from prolonged physical damage to the hair shaft. We report on two adolescent Sikh brothers who wore a turban since early childhood and developed a band-like scarring alopecia at the frontal hairline. Awareness of this condition may help in preventing irreversible hair loss by early modification of the daily hair care routine.

Paradoxical hypertrichosis after laser therapy: a review.

BACKGROUND: Laser hair removal is a safe and effective procedure for the treatment of unwanted body hair but is not exempt from side effects. A rare but significant adverse effect with this treatment modality is paradoxical hypertrichosis. OBJECTIVE: To evaluate the potential etiologies, risk factors, related laser types, and treatment options for the development of excess hair after laser therapy. MATERIALS AND METHODS: An analysis of previously published case studies and review articles along with our own experience was used to gather information regarding this phenomenon. RESULTS: Paradoxical hypertrichosis has a low incidence, ranging from 0.6% to 10%, and most commonly occurs on the face and neck. All laser and light sources have the potential to cause hair induction, especially in individuals with darker skin types (III-VI); with dark, thick hair; and with underlying hormonal conditions. Possible causes include the effect of inflammatory mediators and subtherapeutic thermal injury causing induction of the hair cycle. Treatment for paradoxical hypertrichosis is laser therapy of the affected area. CONCLUSIONS: Paradoxical hypertrichosis is a rare side effect of laser hair removal; the pathogenesis of this event remains widely unknown. We recommend further large-scale studies to investigate this effect. The authors have indicated no significant interest with commercial supporters.

Effect of liposomes containing antioxidant, phospholipid, and amino acid on skin regeneration after chemical burn.

Liposomes containing natural flavonoid dihydroquercetin, phospholipid lecithin, and zwitterionic amino acid glycine were used for the therapy of glacial acetic acid-induced chemical burn. No inflammatory reaction was observed in the region of wound. The area of postburn injury did not increase in time. Planimetry and histological studies showed that improved skin regeneration was accompanied by repair of hair follicles and sebaceous glands.