RESUMO
Transforming Growth Factor Beta 1 (TGFß1) is a multifunctional cytokine that regulates proliferation, apoptosis, and epithelial-mesenchymal transition of epithelial cells. While its role in cancer is well studied, less is known about TGFß1 and regulation of epithelial development. To address this, we deleted TGFß1 in basal keratinocytes of stratified squamous epithelia. Newborn mice with a homozygous TGFß1 deletion had significant defects in proliferation and differentiation of the epidermis and oral mucosa, and died shortly after birth. Hair follicles were sparse in TGFß1 depleted skin and had delayed development. Additionally, the Wnt pathway transcription factor LEF1 was reduced in hair follicle bulbs and nearly absent from the basal epithelial layer. Hemizygous knockout mice survived to adulthood but were runted and had sparse coats. The skin of these mice had irregular hair follicle morphology and aberrant hair cycle progression, as well as abnormally high melanin expression and delayed melanocyte migration. In contrast to newborn TGFß1 null mice, the epidermis was hyperproliferative, acanthotic and inflamed. Expression of p63, a master regulator of stratified epithelial identity, proliferation and differentiation, was reduced in TGFß1 null newborn epidermis but expanded in the postnatal acanthotic epidermis of TGFß1 hemizygous mice. Thus, TGFß1 is both essential and haploinsufficient with context dependent roles in stratified squamous epithelial development and homeostasis.
Assuntos
Carcinoma de Células Escamosas , Queratinócitos , Animais , Carcinoma de Células Escamosas/metabolismo , Diferenciação Celular , Epiderme/metabolismo , Epitélio/metabolismo , Folículo Piloso , Melanócitos , CamundongosRESUMO
BACKGROUND: Formaldehyde is a common preservative used to prevent microbial growth in water. It can be found in personal care products and household cleaning products, including laundry detergents. Formaldehyde has frequently been recognised as a cause of allergic contact dermatitis, but whether it remains present in textiles washed with formaldehyde-containing laundry detergents is unknown. OBJECTIVES: This study aimed to utilise the chromotropic acid method (CAM) to assess formaldehyde release from textiles washed with a laundry detergent known to contain formaldehyde. MATERIALS AND METHODS: Textiles were laundered with a detergent containing calcium formate at four concentrations (0×, 0.5×, 1× and 5× the recommended amount per manufacturer label) and kept wet or allowed to dry. Select textiles were subjected to an additional rinse cycle. Textiles were then tested utilising the CAM. A sample of the pure laundry detergent was also tested using the CAM. RESULTS: The CAM was positive only for wet textiles washed at 5× the recommended concentration of detergent and pure detergent. All dry textiles were negative. CONCLUSIONS: Formaldehyde release was not detected from any textiles washed following the manufacturer's recommendations. Once dry, it is likely safe for formaldehyde-allergic patients to wear textiles washed with formaldehyde-containing detergents.
Assuntos
Dermatite Alérgica de Contato , Detergentes , Humanos , Sabões , Alérgenos , Formaldeído , TêxteisRESUMO
Platelet α-granules release growth factors (GFs) that promote healing and tissue regeneration. Platelet-rich plasma (PRP) is shown to be beneficial in treating alopecia, and however, clinical response can be inconsistent. Due to several fold enrichment of platelets secreting large quantities of GFs following PRP injections, heterogeneity in amounts of GFs secreted by platelets may contribute to inconsistent clinical responses. Herein, we evaluated factors that could potentially contribute to heterogeneous secretion of GFs by platelets. We measured platelet secretion of transforming growth factor beta1 (TGFß1), platelet-derived growth factor (PDGF-BB), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF2) in aliquots of de-identified PRP samples from female patients undergoing therapy in the hair disease clinic. Although secretion of GFs by platelets was comparable in PRP samples of patients with non-cicatricial and cicatricial alopecia, a Shapiro-Wilk test for normal distribution indicated significant variability across all patient samples. The amount of GF secreted by platelets was comparable when PRP prepared from two FDA-cleared devices with distinct techniques were compared. We provide evidence of platelets secreting heterogeneous amounts of GFs within each sample as high and low secretion of random factors could be simultaneously detected. These results suggest inherent heterogeneity in secretion of GFs by platelets in patient samples that are not influenced by the device used to prepare PRP. Since some GFs could have antagonistic effects on hair growth, a balance between amounts of growth promoting and inhibiting factors may be crucial in determining clinical response to PRP therapy.
Assuntos
Alopecia/sangue , Plaquetas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Plasma Rico em Plaquetas/metabolismo , Adulto , Idoso , Alopecia/terapia , Becaplermina/genética , Becaplermina/metabolismo , Separação Celular/instrumentação , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto JovemRESUMO
BACKGROUND: Popularity of eyelash enhancements has increased dramatically. Eyelash enhancements are available as an over-the-counter consumer product with glue included and as a professional product where proprietary glues are typically used. Both types of eyelash extension glues may release formaldehyde despite not being declared as an ingredient. Although formaldehyde is a carcinogen and may cause allergic contact dermatitis, few studies have assessed its presence in eyelash glues. OBJECTIVE: The aim of the study was to evaluate professional and consumer eyelash glues for the presence of formaldehyde using the chromotropic acid method (CAM). METHODS: A total of 37 eyelash glues were evaluated: 17 consumer eyelash glues (2 of which declared formaldehyde) and 20 professional eyelash glues (none of which declared formaldehyde) were purchased and analyzed with the CAM of testing. RESULTS: For consumer eyelash glues, the 2 glues that declared formaldehyde were positive on CAM testing as well as 2 glues (13.3% [2/15]) that did not declare formaldehyde. Of the 20 professional eyelash glues, 15 (75.0%) were positive for formaldehyde. CONCLUSIONS: Some consumer eyelash glues and most professional eyelash glues released formaldehyde when evaluated with CAM. Patients and clinicians should be aware that both consumer and professional eyelash glues can be sources of formaldehyde.
Assuntos
Dermatite Alérgica de Contato , Formaldeído , Humanos , Formaldeído/efeitos adversos , Naftalenossulfonatos , Dermatite Alérgica de Contato/etiologiaRESUMO
BACKGROUND: Aerosolized liquid (e-liquid) of electronic cigarettes can be toxic. Beyond the solvent (propylene glycol, vegetable glycerin) and nicotine, little is known about the liquid composition. Formaldehyde, a carcinogen and source of contact dermatitis, has been reported in the vaporized e-liquid, but no studies have assessed the actual e-liquid. OBJECTIVE: The aim of the study was to evaluate e-liquid products for the presence of formaldehyde. METHODS: Sixteen e-liquid products were purchased and analyzed for the release of formaldehyde using the chromotropic acid method of detection. RESULTS: Of the 16 e-liquids purchased, 4 (25%) were positive for the presence of formaldehyde; 2 were flavored and 2 were nonflavored. All positive e-liquids were in pods or disposable electronic cigarette devices, and 2 were purchased from local vape shops. The average nicotine content in the positive e-liquids was 3.85% versus 4.03% in the negative e-liquids. CONCLUSIONS: The e-liquid products contain toxic chemicals not declared on product labels, as shown in this study with 25.0% of e-liquids containing formaldehyde. All positive e-liquids were within pods or disposable devices. Continued analysis of e-liquids and increased product regulation are needed.