Pilomatrixoma (Epitelioma Calcificante de Malherbe) da região temporal - relato de caso / Pilomatricoma (calcifying epithelioma of Malherbe) of the temporal region - a case report

O pilomatrixoma constitui uma neoplasia benigna incomum de folículos pilosos, observado mais frequentemente em crianças. O tumor apresenta-se como um nódulo solitário e firme, recoberto com epiderme normal. É relatado o caso de uma paciente feminina de 26 anos com lesão na região temporal. Nos cortes histológicos, observou-se uma proliferação expansiva de ilhotas de células epiteliais configuradas de forma irregular, mostrando na área central sombra de núcleos perdidos (células- fantasma). O pilomatrixoma deve ser considerado no diagnóstico diferencial de nódulos cutâneos, especialmente aqueles de cabeça, pescoço e membros superiores.

Pilomatricoma is an uncommon benign neoplasm of hair follicles, most commonly seen in children. The tumor appears as a solitary and firm nodule, covered with normal epidermis. We report the case of a 26-year-old woman with a lesion in the temporal region. In histological sections, there was an expansive proliferation of islets of epithelial cells configured irregularly, showing the shadow of lost nuclei (ghost cells) in the central area. Pilomatricoma should be considered in the differential diagnosis of skin nodules, especially those of the head, neck, and upper limbs

NANOG Alleviates the Damage of Human Hair Follicle Mesenchymal Stem Cells Caused by H2O2 through Activation of AKT Pathway / 生物医学与环境科学（英文）

OBJECTIVE@#To explore the protective effect of NANOG against hydrogen peroxide (H2O2) -induced cell damage in the human hair follicle mesenchymal stem cells (hHF-MSCs).@*METHODS@#NANOG was expressed from a lentiviral vector, pLVX-IRES-ZsGreen. NANOG hHF-MSCs and vector hHF-MSCs were treated with 400 μmol/L hydrogen peroxide (H2O2) for 2 h, the cell survival rate, cell morphology, ROS production, apoptosis and expression of AKT, ERK, and p21 were determined and compared.@*RESULTS@#Our results showed that NANOG could activate AKT and upregulate the expression of p-AKT, but not p-ERK. When treated with 400 μmol/L H2O2, NANOG hHF-MSCs showed higher cell survival rate, lower ROS production and apoptosis, higher expression of p-AKT, higher ratio of p-AKT/AKT.@*CONCLUSION@#Our results suggest that NANOG could protect hHF-MSCs against cell damage caused by H2O2 through activating AKT signaling pathway.

MiR-214 Regulates the Human Hair Follicle Stem Cell Proliferation and Differentiation by Targeting EZH2 and Wnt/β-Catenin Signaling Way In Vitro

miR-214 plays a major role in the self-renewal of skin tissue. However, whether miR-214 regulates the proliferation and differentiation of human hair follicle stem cells (HFSCs) is unknown. Primary HFSCs were isolated from human scalp skin tissue, cultured, and identified using flow cytometry. An miR-214 mimic and inhibitor were constructed for transfection into HFSCs. The MTS and colony formation assays examined cell proliferation. Immunofluorescence detected the localization and expression levels of TCF4, β-catenin, and differentiation markers. Luciferase reporter and TOP/FOP Flash assays investigated whether miR-214 targeted EZH2 and regulated the Wnt/β-catenin signaling pathway. Western blot determined the expression levels of enhancer of zeste homolog 2 (EZH2), Wnt/β-catenin signaling-related proteins, and HFSC differentiation markers in cells subjected to miR-214 transfection. miR-214 expression was remarkably decreased during the proliferation and differentiation of HFSCs into transit-amplifying (TA) cells. Downregulation of miR-214 promotes the proliferation and differentiation of HFSCs. Overexpression of miR-214 led to decreased expression of EZH2, β-catenin, and TCF-4, whereas downregulation of miR-214 resulted in increased expression of EZH2, β-catenin, and TCF-4 as well as TA differentiation markers. Immunofluorescence assay revealed that inhibiting miR-214 triggered the entry of β-catenin and TCF-4 into the nucleus. The luciferase reporter and TOP/FOP Flash assays demonstrated that miR-214 directly targets EZH2 and affects Wnt/β-catenin signaling. The miR-214/EZH2/β-catenin axis could be considered a candidate target in tissue engineering and regenerative medicine for HFSCs.

Progress in the mechanisms of keratoacanthoma regression / 实用肿瘤学杂志

Keratoacanthoma ( KA) is an epithelial neoplasm occurring in sun -exposed skin of the elder-ly.Two striking features of KA are its clinical behavior with spontaneous regression after rapid growth and its nos -ological position on the border between benignity and malignancy .The regression of KA may be associated with the hair follicle cycle,apoptosis and immune function of organism .This article summarizes physiological mecha-nisms such as Wnt/retinoic acid signalling cross -talk,the function of p53,bcl-2,bcl-xL and bak in apopto-sis,and the mechanism of action of several immune -related cells,that drives KA regression .It can provide theo-retical basis for us to select the method as well as time of the treatment in KA .

Dynamic life of a skin keratinocyte: An intimate tryst with the master regulator p63.

Skin keratinocytes form a tightly knit and layered epithelium at the surface of the body protecting the body from the outside environment. The formation and maintenance of skin epidermis is governed by dynamic and well-coordinated processes of cell proliferation, differentiation, and self-renewal. Such important cell fate decisions are made possible in part by transcription factors, which activate and repress unique sets of genes in a temporal and spatial pattern. The Tp63 gene encodes for multiple isoforms for one such transcription factor that serves as a key regulator of epidermal development and differentiation. The crucial function of p63 is epitomized by the phenotype of p63 knockout mice – in the absence of p63, there is a profound block in the development of skin epidermis and all related appendages such as hair follicles. Human syndromes resulting from Tp63 gene mutations phenocopy the p63 knockout phenotype, highlighting the evolutionarily conserved function of this factor in epithelial biology. Although the function of p63 as an important hub in transcriptional and signaling networks of keratinocytes is well established, the underlying molecular mechanisms of p63 action is continually redefined with the development of new genetic models and more extensive biochemical analysis. In this review the biological role of Np63, the predominant isoform that is expressed in skin keratinocytes has been described. Results from transgenic animal models that have shed new information on the function of Np63 in the epidermis and hair follicles have been discussed. Further, the molecular mechanisms that maintain the fine-tuned expression of Np63 in skin keratinocytes are also described.

Effect of topical tacrolimus on xenogeneic hair follicle transplantation / 中华医学美学美容杂志

Objective To study the effect of topical tacrolimus (FK506) on the survival of the xenogeneic transplanted hair follicles from human scalp to Wistar rats. Methods In our study, Wistar rats were used as recipients and human as donor. The black hair follicles of human scalp were harvested, and then the xenogeneic grafts were transplanted to white Wistar rats on the back. 20 couples of rats were divided in 2 groups: topical tacrolimus group (group A), and blank control group (group B). After operaton, we compared the survival time of hair follicles and their histologic outcomes in order to verify the practicability of xenogeneic transplantion of hair follicles, and the topical application of tacrolimus results.Results The mean survival time of group A was longer [(49. 9 ±7. 1) days] as compared to group B [(13. 1±1. 2) days]. The longest survival time was 65 days in group A and 14 days in group B, respectively. By comparison of the results we found that topical tacrolimus prolonged the survival time of the xenotransplanted hair follicles significantly and that tropical medication could not avoid rejection. Conclusions The immune privilege function dependent on the hair follicle anagen and axillary topical tacrolimus, can prolong the survival time of the xenogeneic transplanted hair follicles in rats significantly.

Effect of Wnt-3a signaling on aggregative growth of dermal papilla cells:a pilot study / 中华皮肤科杂志

Objective To investigate the influence of Wnt-3a signaling on aggregative growth of dermal papilla cells.Methods Recombinant adenovirus pAdEasy-1/Wnt-3a was constructed at first,and used to transfect cultured dermal papilla cells(DPCs).Then,the growth pattem of DPCs was observed by inverse microscopy;laser confocal microscopy and Western blot were utilized to detect the expressions of Wnt-3a,β-catenin and versican in low-passage DPCs,high-passage DPCs and transfected high-passage DPCs.Results The over-expression of Wnt-3a protein could effectively induce the aggregative growth of DPCs.Laser confocal microscopy showed that the fluorescence intensity of β-catenin and versican increased from 34.16±9.62 and 18.81±9.59 in high-passage DPCs to 87.35±17.28 and 92.18±18.39 in transfected high-passage DPCs(t=11.98,17.88,both P＜0.0 1),respectively.Also,Western blot proved a significant increase of expression intensity of β-catenin(15.27±2.17 vs 60.09±7.24,t=10.10,P＜0.01)and versican(19.32±2.46 vs 58.46±2.78,t=20.63,P＜0.01)in transfected high-passage DPCs compared with untransfected high-passage DPCS.ConclusionsWnt-3a signaling plays an important role in modulating aggregative growth of DPCs,which is mainly through the classical pathway with β-catenin as the key protein.As an important downstream gene of Wnt signaling,vesican is an indispensable part for the modulation of aggregative growth of DPCs.

Color-dilution alopecia in dogs

Color-dilution alopecia is a relatively uncommon hereditary skin disease seen in "Blue" and other color-diluted dogs. This syndrome is associated with a color-dilution gene. The initial clinical signs are the gradual onset of a dry, dull and poor hair coat quality. Hair shafts and hair regrowth are poor, and follicular papules may develop and progress to frank comedones. Hair loss and comedo formation are usually most severe on the trunk, especially color-diluted area on the skin. Six cases of color-dilution alopecia are reported in 3 months to 10 years old dogs. The breeds of dogs are blue Doberman Pinscher, Miniature Pinscher, Dachshund, and Schnauzer. Grossly, extensive partial hair loss was seen on the skin. Histopathologically, the epidermis is relatively normal but may be hyperplastic. Hair follicles are characterized by atrophy and distortion. Heavily clumped melanin is present in the epidermis, dermis and hair follicles.

A Case of Rabies Diagnosis by Skin Biopsy Including Hair Follicles on the Posterior Neck / 대한피부과학회지

Rabies is a fatal infection of the central nervous system acquired most often through a virus transmitted in saliva by a rabid animal. It is important to rapidly and accurately identify the rabies virus so that appropriate rabies preventive measures can be initiated to the general population. However, the diagnosis of clinical rabies is difficult and is often not made until after death of the patient. Early in the course of illness, the most reliable diagnostic test is a nuchal skin biopsy including hair follicles with fluorescent antibody staining or with PCR. We report a case of rabies diagnosis with hair follicle from a patient suspected of having the infection. It is the first case reported in Korea that the diagnosis of rabies was made on a skin biopsy.

A Clinical and Pathologic Study on Becker' s Melanosis / 대한피부과학회지

BACKGROUND: Becker's mealanosis is not an uncommon entity, and many cases are probably not reported because the diagnosis is usually made clinically and the condition is benign with cosmetic significance only. the etiology remains obscure. OBJECTIVE: The purpose of this study is to establish the clinicopathologic characteristics of Becker's melanosis in Korean. METHODS: Thirty-six patients with Becker's melanosis were retrospectively studied. RESULTS: The clinical and histopathologic findings observed in our cases were similar to previous reports except for the following. Nine patients(25%) had abnormal findings in their hair follicles : dilatation of the infundibular portion filled with abnormal keratin, Pityrosporum orbiculare and bacteria(19.4%); formation of intrafollicular cyst(5.6%). Three patients(8.3%) had granulomatous infiltration. Twenty-two patients(61.1%) had increased smooth muscle bundles. CONCLUSION: The findings associated with dermal hair follicles may be related to the pathogenesis of Becker's melanosis.

Two cases of trichofolliculoma / 대한피부과학회지

Trichofolliculoma is an adnexal tumor of hair follicle oriyin, considered to be of intermediate differentiation between a hair follicle nevus, a simple hyperolasia of the hair follicle, and trichoepithelioma, Which usually lacks mature hair follicles. Grossly the tumor usually appears on the head or neck as a 0.5 to 1.0cm solitary white to pearly papule, Many lesions show a cental pore, and occasionally woolly or cottony hairs may protrude from this pore. Histologically, trichofolliculomas are characterized by a central dilated follicle filled with keratin or hair. Radiating from this primary hair follicle are numerous secndary hair follicles of varying degrees of maturation. An organized fibro-vascular stroma surrounds these epithelial structure, giving it a well-defined nodular appearance. We presented here two case of trichofolliculoma with typical clnical and histopathological findings, one in a 65 year-old female and the other a 56 year-old males.

Two cases of trichofolliculoma / 대한피부과학회지

Trichofolliculoma is an adnexal tumor of hair follicle oriyin, considered to be of intermediate differentiation between a hair follicle nevus, a simple hyperolasia of the hair follicle, and trichoepithelioma, Which usually lacks mature hair follicles. Grossly the tumor usually appears on the head or neck as a 0.5 to 1.0cm solitary white to pearly papule, Many lesions show a cental pore, and occasionally woolly or cottony hairs may protrude from this pore. Histologically, trichofolliculomas are characterized by a central dilated follicle filled with keratin or hair. Radiating from this primary hair follicle are numerous secndary hair follicles of varying degrees of maturation. An organized fibro-vascular stroma surrounds these epithelial structure, giving it a well-defined nodular appearance. We presented here two case of trichofolliculoma with typical clnical and histopathological findings, one in a 65 year-old female and the other a 56 year-old males.