BACKGROUND There are different stem cell pools located in the hair follicle. OBJECTIVE To try to determine whether follicular units can survive a partial extraction and whether this partial extracted follicular unit can regenerate new hairs. METHODS From five individuals, between 100 and 150 grafts were harvested from the occipital area of the scalp. Suitable grafts were implanted into the ...

MicroRNAs (miRNAs) regulate the expression of many mammalian genes and play key roles in embryonic hair follicle development; however, little is known of their functions in postnatal hair growth. We compared the effects of deleting the essential miRNA biogenesis enzymes Drosha and Dicer in mouse skin epithelial cells at successive postnatal time points. Deletion of either Drosha or Dicer during...

In previous communications we reported that under certain experimental conditions systemic cortisone administration accelerated the occurrence of chemically induced epidermal tumors in mice (15-17, 30, ~6). The results were confirmed by Spain, Molomut, and Novikoff (95). We postulated that this effect is caused by an inhibitory influence of the steroid on hair follicular growth (15-17, 34). Thi...

Objectives: This study was designed to investigate the potential Phyllanthus niruri extracts in promotion of hair growth. Materials and Methods: Here, we studied the hair growth promoting activity of petroleum ether extract of P. niruri following its topical administration. Alopecia was induced in albino rats by subcutaneous administration of testosterone for 21 days. Evaluation of hair loss in...

Panfolliculoma is a distinctive and unusual benign follicular neoplasm. It shows differentiation towards all components of the hair follicle, including the upper and the lower segments. We report two cases of this rare disease. The first patient presented with a painful nodule on the scalp and the second patient had an asymptomatic skin-colored nodule on his left eyebrow. Histopathologic examin...

This simple idea may not seem like a radical approach to hair transplantation, but when viewed in the context of how the surgery has been performed over the past forty years (when the very existence of the follicular unit went generally unrecognized), it is radical indeed. At present, the majority of hair transplant surgeons will, at times, combine several follicular units or split them up, as ...

AIMS Follicular drug delivery is the prerequisite for an effective treatment of androgenetic alopecia or other reasons of premature hair loss. METHODS The follicular penetration of caffeine, applied topically in a shampoo formulation for 2 min, was measured with highly sensitive surface ionization in combination with mass spectroscopy, a selective method for the detection of very small quanti...

We analyzed changes of growth and apoptotic cell death in human hair follicles. In anagen hair follicles, terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate-biotin nick labeling-positive cells were observed in the keratogenous zone of the upper bulb matrix, the inner root sheath, and the companion layer of the outer root sheath. DNA ladder formation was also detected in ana...

Hair transplantation is a continuously evolving field. Since 1959, when Orentreich described the phenomenon of donor dominance in androgenic alopecia, thus paving the way for body-hair transplants, new techniques have not ceased to appear. During the last 15 years, the perception of hair transplantation as an aggressive technique with an artificial result has finally disappeared thanks to the u...

The “follicular-melanin unit” is residing in the “immune privileged” proximal hair bulb [3]. This follicular-melanin unit consists of one melanocyte for every five keratinocytes in the hair bulb as a whole; the ratio is 1:1 in the basal epithelial layer next to the dermal papilla [4]. Hair bulb melanogenic melanocytes differ from epidermal melanocytes in being larger, with longer and more exten...