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1.
J Am Acad Dermatol ; 89(2S): S9-S15, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37591567

RESUMEN

Trichoscopy is currently regarded as an essential part of the hair loss consultation. It allows visualization of morphologic structures that are not obvious to the naked eye, including peri- and interfollicular skin surface abnormalities and changes to hair shaft thickness and shape. In this paper, we aim to discuss current knowledge on trichoscopy of the most common forms of scarring and nonscarring alopecias.


Asunto(s)
Alopecia , Cicatriz , Humanos , Cicatriz/diagnóstico por imagen , Alopecia/diagnóstico por imagen , Cabello/diagnóstico por imagen , Instituciones de Atención Ambulatoria , Derivación y Consulta
2.
Skin Res Technol ; 29(4): e13203, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37113095

RESUMEN

BACKGROUND: The removal of hair and ruler marks is critical in handcrafted image analysis of dermoscopic skin lesions. No other dermoscopic artifacts cause more problems in segmentation and structure detection. PURPOSE: The aim of the work is to detect both white and black hair, artifacts and finally inpaint correctly the image. METHOD: We introduce a new algorithm: SharpRazor, to detect hair and ruler marks and remove them from the image. Our multiple-filter approach detects hairs of varying widths within varying backgrounds, while avoiding detection of vessels and bubbles. The proposed algorithm utilizes grayscale plane modification, hair enhancement, segmentation using tri-directional gradients, and multiple filters for hair of varying widths. We develop an alternate entropy-based processing adaptive thresholding method. White or light-colored hair, and ruler marks are detected separately and added to the final hair mask. A classifier removes noise objects. Finally, a new technique of inpainting is presented, and this is utilized to remove the detected object from the lesion image. RESULTS: The proposed algorithm is tested on two datasets, and compares with seven existing methods measuring accuracy, precision, recall, dice, and Jaccard scores. SharpRazor is shown to outperform existing methods. CONCLUSION: The Shaprazor techniques show the promise to reach the purpose of removing and inpaint both dark and white hair in a wide variety of lesions.


Asunto(s)
Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/patología , Dermoscopía/métodos , Cabello/diagnóstico por imagen , Cabello/patología , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos
3.
Skin Pharmacol Physiol ; 36(2): 67-75, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36470219

RESUMEN

BACKGROUND: Trichoscopy is a simple, noninvasive procedure practiced in the diagnosis of a multitude of scalp and hair disorders. Hair shaft abnormalities usually represent a diagnostic challenge to dermatologists. OBJECTIVES: The aim of the study was to determine the practicality, versatility, and value of using the handheld dermoscope in the assessment of hair shaft abnormalities and the diagnosis of different hair/scalp disorders. METHODS: Eight hundred and seven patients of both sexes, aged from 1 to 76 years, with complaints pertaining to scalp and hair, were the subjects of the study. All patients were examined by the handheld dermoscope, and 400 were additionally examined by the folliscope, digital dermoscope, or their hairs mounted for light microscopy. RESULTS: Based on trichoscopic findings, more than half the patients demonstrated thinned terminal hairs and a predominance of single-haired scalp pilosebaceous units (57% and 55.5%, respectively). Over a quarter of the patients showed hair diameter heterogeneity, upright regrowing hairs, and increased vellus hairs (37%, 31%, and 25%, respectively). Other trichoscopic findings included scalp scaling (19%), hair weathering (12%), thinned wavy hairs (10.5%), brush-like hair fractures (9%), exclamation mark hairs (9%), and longitudinal cleavage (trichoptilosis) (8%). The clinical diagnostic spectrum was topped by the following diagnoses in order of frequency: female pattern hair loss, telogen effluvium, traction alopecia, and trichotillomania. Trichodynia appeared to be significantly associated with numerous hair shaft abnormalities. CONCLUSION: Most hair shaft abnormalities can be reliably diagnosed with high accuracy using a handheld dermoscope in an office setting. Skillful knowledge of dermoscopy is an important aid in the diagnosis of hair and scalp disorders.


Asunto(s)
Alopecia Areata , Dermoscopía , Masculino , Humanos , Femenino , Estudios Transversales , Dermoscopía/métodos , Cabello/diagnóstico por imagen , Cuero Cabelludo
4.
J Digit Imaging ; 36(2): 526-535, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36385676

RESUMEN

Hair and ruler mark structures in dermoscopic images are an obstacle preventing accurate image segmentation and detection of critical network features. Recognition and removal of hairs from images can be challenging, especially for hairs that are thin, overlapping, faded, or of similar color as skin or overlaid on a textured lesion. This paper proposes a novel deep learning (DL) technique to detect hair and ruler marks in skin lesion images. Our proposed ChimeraNet is an encoder-decoder architecture that employs pretrained EfficientNet in the encoder and squeeze-and-excitation residual (SERes) structures in the decoder. We applied this approach at multiple image sizes and evaluated it using the publicly available HAM10000 (ISIC2018 Task 3) skin lesion dataset. Our test results show that the largest image size (448 × 448) gave the highest accuracy of 98.23 and Jaccard index of 0.65 on the HAM10000 (ISIC 2018 Task 3) skin lesion dataset, exhibiting better performance than for two well-known deep learning approaches, U-Net and ResUNet-a. We found the Dice loss function to give the best results for all measures. Further evaluated on 25 additional test images, the technique yields state-of-the-art accuracy compared to 8 previously reported classical techniques. We conclude that the proposed ChimeraNet architecture may enable improved detection of fine image structures. Further application of DL techniques to detect dermoscopy structures is warranted.


Asunto(s)
Melanoma , Enfermedades de la Piel , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/patología , Redes Neurales de la Computación , Algoritmos , Dermoscopía/métodos , Cabello/diagnóstico por imagen , Cabello/patología , Procesamiento de Imagen Asistido por Computador/métodos
5.
Skin Res Technol ; 28(5): 689-694, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35726958

RESUMEN

BACKGROUND: Vellus hair is the fine, wispy hair found over most of the body surface, and the arrector pili muscles (hair muscle) serve to raise these hairs. Hair muscles are also critical for skin regeneration, contributing to the maintenance of stem cells in epidermis and hair follicles. However, little is known about their fundamental properties, especially their structure, because of the limitations of conventional two-dimensional histological analysis. OBJECTIVES: We aimed to quantitatively characterize the structure of vellus hair muscles by establishing a method to visualize the 3D structure of hair muscle. METHODS: We observed young female abdominal skin specimens by means of X-ray micro CT and identified hair muscles in each cross-sectional CT image. We then digitally reconstructed the 3D structure of the hair muscles on computer (digital-3D skin), and numerically evaluated their structural parameters. RESULTS: Vellus hair muscles were clearly distinguished from the surrounding dermal layer in X-ray micro CT images and were digitally reconstructed in 3D from those images for quantification of the structural parameters. The mean value of number of divisions of vellus hair muscles was 1.6, mean depth was 943.6 µm from the skin surface, mean angle to the skin surface was 28.8 degrees, and mean length was 1657.9 µm. These values showed relatively little variation among subjects. The mean muscle volume was approximately 20 million µm3 but showed greater variability than the other parameters. CONCLUSION: Digital-3D skin technology is a powerful approach to understand the tiny but complex 3D structure of vellus hair muscles. The fundamental nature of vellus hair muscles was characterized in terms of their 3D structural parameters, including number of divisions, angle to the skin surface, depth, and volume.


Asunto(s)
Folículo Piloso , Cabello , Femenino , Cabello/diagnóstico por imagen , Folículo Piloso/diagnóstico por imagen , Folículo Piloso/patología , Humanos , Músculo Liso , Piel/diagnóstico por imagen , Tomografía Computarizada por Rayos X
6.
J Clin Immunol ; 41(5): 1064-1071, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33675005

RESUMEN

Cartilage-hair hypoplasia is a syndromic immunodeficiency with short stature, chondrodysplasia, and variable degree of immune dysfunction. Patients with cartilage-hair hypoplasia are prone to recurrent respiratory tract infections, and the prevalence of bronchiectasis ranges from 29 to 52%. Pulmonary complications contribute significantly to the mortality; therefore, regular lung imaging is essential. However, the optimal schedule for repeated lung imaging remains unestablished. We determined the rate and correlates of progression of structural lung changes in a prospectively followed cohort of 16 patients with cartilage-hair hypoplasia. We analyzed clinical, laboratory, and pulmonary functional testing data and performed lung magnetic resonance imaging at a median interval of 6.8 years since previous imaging. Imaging findings remained identical or improved due to disappearance of inflammatory changes in all evaluated patients. Patients with subtle signs of bronchiectasis on imaging tended to have low immunoglobulin M levels, as well as suffered from pneumonia during the follow-up. In conclusion, our results suggest slow if any development of bronchiectasis in selected subjects with cartilage-hair hypoplasia.


Asunto(s)
Bronquiectasia/diagnóstico por imagen , Cabello/anomalías , Enfermedad de Hirschsprung/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Osteocondrodisplasias/congénito , Enfermedades de Inmunodeficiencia Primaria/diagnóstico por imagen , Adolescente , Adulto , Anciano , Bronquiectasia/sangre , Femenino , Cabello/diagnóstico por imagen , Enfermedad de Hirschsprung/sangre , Humanos , Inmunoglobulina M/sangre , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteocondrodisplasias/sangre , Osteocondrodisplasias/diagnóstico por imagen , Neumonía/sangre , Neumonía/diagnóstico por imagen , Enfermedades de Inmunodeficiencia Primaria/sangre , Estudios Prospectivos , Adulto Joven
7.
Opt Express ; 29(20): 32179-32195, 2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-34615295

RESUMEN

Full-field swept-source optical coherence tomography (FF-SS-OCT) is an emerging technology with potential applications in ophthalmic imaging, microscopy, metrology, and other domains. Here we demonstrate a novel method of multiplexing FF-SS-OCT signals using carrier modulation (CM). The principle of CM could be used to inspect various properties of the scattered light, e.g. its spectrum, polarization, Doppler shift, or distribution in the pupil. The last of these will be explored in this work, where CM was used to acquire images passing through two different optical pupils. The two pupils contained semicircular optical windows with perpendicular orientations, with each window permitting measurement of scattering anisotropy in one dimension by inducing an optical delay between the images formed by the two halves of the pupil. Together, the two forms of multiplexing permit measurement of differential scattering anisotropy in the x and y dimensions simultaneously. To demonstrate the feasibility of this technique our carrier multiplexed directional FF-OCT (CM-D-FF-OCT) system was used to acquire images of a microlens array, human hair, onion skin and in vivo human retina. The results of these studies are presented and briefly discussed in the context of future development and application of this technique.


Asunto(s)
Luz , Dispersión de Radiación , Tomografía de Coherencia Óptica/métodos , Anisotropía , Artefactos , Estudios de Factibilidad , Análisis de Fourier , Cabello/diagnóstico por imagen , Humanos , Interferometría , Cebollas , Retina/diagnóstico por imagen , Células Fotorreceptoras Retinianas Conos/fisiología , Semiconductores , Tomografía de Coherencia Óptica/instrumentación , Tomografía de Coherencia Óptica/tendencias
8.
Skin Res Technol ; 27(2): 201-207, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33128476

RESUMEN

BACKGROUND: Hair loss is a common problem in dermatological patients. Its diagnosis is based on selected non-invasive and invasive tests. Searching for new diagnostic methods, especially non-invasive ones, aims to accelerate the correct diagnosis in the least invasive way possible. The aim of our study was to establish the characteristics of ultrasound images in healthy individuals and to compare them to selected trichoscopic parameters. MATERIALS AND METHODS: Eighteen healthy adults (10 women and 8 men) underwent trichoscopy and high-frequency ultrasound (HF-USG) with 20 MHz DermaScan transducer on the parietal region of the scalp. Selected parameters were compared in relation to sex and the research method used. RESULTS: HF-USG of the parietal area in all examined patients revealed hyperechogenic entrance echo and less echogenic layer corresponding to the dermis with well-defined hypoechoic follicular structures (FS). The number of hair units in trichoscopy and the number of FS in HF-USG did not differ significantly, while the differences in the studied distances between structures were statistically significant. The width of FS in HF-USG was significantly higher than hair shafts thickness in trichoscopy. CONCLUSIONS: HF-USG (20MHz) due to the possibility of visualization of FS can be a valuable complement to the range of non-invasive diagnostic procedures used in evaluation of the scalp.


Asunto(s)
Dermoscopía , Cuero Cabelludo , Adulto , Alopecia , Femenino , Cabello/diagnóstico por imagen , Humanos , Masculino , Cuero Cabelludo/diagnóstico por imagen , Ultrasonografía
9.
J Drugs Dermatol ; 20(1): 55-61, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33400421

RESUMEN

Hair loss is a complex and multi-factorial problem that is associated with significant psychological morbidity in women. Menopausal women represent a significant percentage of those affected, since the menopausal hormonal transition can be a contributing factor. A novel nutraceutical supplement has been specifically formulated with phytoactives to improve hair growth and quality in menopausal women (Nutrafol® Women’s Balance Capsules). The objective of this 6-month, randomized, double-blind, placebo-controlled study was to assess the safety and efficacy of this oral supplement to promote hair growth in perimenopausal, menopausal, and postmenopausal women with self-perceived thinning. Subjects were randomized to the study supplement (n=40) or placebo (n=30). The primary endpoint was a statistically significant increase in the number of terminal and vellus hairs based on phototrichogram analysis. Daily intake of the nutraceutical supplement resulted in progressive and significant increase in terminal and total hair counts on days 90 (P<0.01) and 180 (P<0.01) compared to placebo. The vellus hair counts significantly increased for the active treatment group (P<0.05) by day 180 while significantly decreasing for the placebo group subjects. Hair shedding progressively and significantly decreased for the active group compared to placebo, culminating in a reduction of 32.41% by day 180 (P<0.01). The study supplement was well-tolerated. ClinicalTrials.gov Identifier: NCT04048031 J Drugs Dermatol. 2021;20(1):55-61. doi:10.36849/JDD.5701 THIS ARTICLE HAD BEEN MADE AVAILABLE FREE OF CHARGE. PLEASE SCROLL DOWN TO ACCESS THE FULL TEXT OF THIS ARTICLE WITHOUT LOGGING IN. NO PURCHASE NECESSARY. PLEASE CONTACT THE PUBLISHER WITH ANY QUESTIONS.


Asunto(s)
Alopecia/tratamiento farmacológico , Suplementos Dietéticos/efectos adversos , Cabello/efectos de los fármacos , Menopausia/fisiología , Fitoquímicos/administración & dosificación , Administración Oral , Adulto , Anciano , Alopecia/diagnóstico , Alopecia/fisiopatología , Dermoscopía/métodos , Método Doble Ciego , Femenino , Cabello/diagnóstico por imagen , Cabello/crecimiento & desarrollo , Humanos , Persona de Mediana Edad , Fotograbar , Fitoquímicos/efectos adversos , Placebos/administración & dosificación , Encuestas y Cuestionarios , Resultado del Tratamiento
10.
Dev Psychobiol ; 63(6): e22147, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34105766

RESUMEN

Socioeconomic disadvantage has been linked to increased stress exposure in children and adults. Exposure to stress in childhood has been associated with deleterious effects on cognitive development and well-being throughout the lifespan. Further, exposure to stress has been associated with differences in brain development in children, both in cortical and subcortical gray matter. However, less is known about the associations among socioeconomic disadvantage, stress, and children's white matter development. In this study, we investigated whether socioeconomic disparities would be associated with differences in white matter microstructure in the cingulum bundle, as has been previously reported. We additionally investigated whether any such differences could be explained by differences in stress exposure and/or physiological stress levels. White matter tracts were measured via diffusion tensor imaging in 58 children aged 5-9 years. Results indicated that greater exposure to stressful life events was associated with higher child hair cortisol concentrations. Further, physiological stress, as indexed by hair cortisol concentrations, were associated with higher fractional anisotropy in the cingulum bundle. These results have implications for better understanding how perceived and physiological stress may alter neural development during childhood.


Asunto(s)
Hidrocortisona , Sustancia Blanca , Adulto , Encéfalo , Niño , Preescolar , Imagen de Difusión Tensora , Cabello/química , Cabello/diagnóstico por imagen , Humanos , Hidrocortisona/análisis , Factores Socioeconómicos , Sustancia Blanca/diagnóstico por imagen
11.
Exp Dermatol ; 29(3): 223-230, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-30307062

RESUMEN

BACKGROUND: Diffuse alopecia areata (DAA) often leads to a complete hair shedding within a few months. OBJECTIVE: To explore features and mechanisms underlying DAA. MATERIALS AND METHODS: Scalp and hair root dermoscopy were conducted on 23 DAA patients throughout the disease process, 20 patchy Alopecia areata patients, 23 acute telogen effluvium (ATE) patients and 10 normal controls. Histopathology was also evaluated. RESULTS: We found almost all hair roots were anagen in early stage DAA in 18 patients (18/23, 78.3%) within the first 4-8 weeks after hair loss onset. Anagen effluvium (~4 weeks) was followed by catagen (~4 weeks) and then telogen/exogen (~8 weeks) effluvium with overlap. Hair root and proximal hair shaft depigmentation was more prominent in later DAA disease stages. Black dots, exclamation mark hairs and inconsistent thickness of hair shafts were found more often in early than later DAA (Ps < 0.01). Early DAA histopathology revealed more prominent inflammation and hair follicle regression than that observed in the later stages. Patchy alopecia areata patients showed mixed anagen, catagen and telogen hair roots while ATE patients showed increased exogen and mildly decreased hair root pigmentation. CONCLUSION: Sequential cyclic staging of shed hairs in DAA indicates the insult may be hair-cycle specific. We suggest that DAA is initially an anagen effluvium disease involving an intense inflammatory insult, later progressing to a brief catagen effluvium, and then to telogen effluvium with premature exogen, in later stages of DAA.


Asunto(s)
Alopecia Areata/diagnóstico por imagen , Dermoscopía/métodos , Folículo Piloso/diagnóstico por imagen , Cabello/diagnóstico por imagen , Adolescente , Adulto , Alopecia/patología , Biopsia , Estudios de Casos y Controles , Femenino , Humanos , Inflamación , Masculino , Persona de Mediana Edad , Pigmentación , Cuero Cabelludo/patología , Adulto Joven
12.
Appl Opt ; 59(29): 9169-9173, 2020 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-33104628

RESUMEN

We report the demonstration of imaging of a single human hair with a terahertz quantum cascade laser (THz-QCL) source based on intracavity difference-frequency generation. A single human hair whose diameter was about 100 µm was detected using the THz-QCL source operating at 240 K, of which the THz beam had a linear polarization. The results show that the THz image of a human hair clearly depends on the polarization direction of the THz beam. The THz QCL sources that are capable of room temperature operation will be useful for detection of small foreign objects like human hairs.


Asunto(s)
Cabello/diagnóstico por imagen , Láseres de Semiconductores , Teoría Cuántica , Radiación Terahertz , Espectroscopía de Terahertz/instrumentación , Humanos
13.
J Drugs Dermatol ; 19(5): 515-518, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32484620

RESUMEN

BACKGROUND: Photoepilation by a single-wavelength laser device is being commonly used for hair removal. Whether emitting multiple laser wavelengths to induce hair unit damage would be beneficial is yet to be established. OBJECTIVE: To evaluate the safety and efficacy of hair reduction using a novel simultaneous multi-wavelength laser device. PATIENTS AND METHODS: A retrospective cohort study was carried out among adult males. Hairy sites were treated by a simultaneous triple-wavelength (755nm, 810nm and 1064nm) laser device (Soprano Titanium. Caesarea, Israel: Alma Lasers Ltd). Treatment parameters were: fluence of 7-9J/cm2, pulse frequency of 9-10Hz and spot sizes of 2cm2 or 4cm2. Participants underwent up to 6 treatments at 6-8 weeks intervals and were followed for 4-6 months. Clinical photography before and after treatment was documented. Treatment efficacy was assessed using Global Aesthetic Improvement Scale (GAIS; scale of 0 [no improvement] to 4 [excellent improvement; Over 75% hair reduction]) by two independent dermatologists. Participants’ satisfaction was rated on a scale of 1 (not satisfied) to 5 (very satisfied). Pain perception and adverse events were recorded as well. RESULTS: A total of 27 treatment sites among 11 participants, with Fitzpatrick skin type III-V, were included. Mean hair reduction was 3.4 out of 4 in the GAIS. Participants' satisfaction rate was high (mean, 4.8). No adverse events were recorded. CONCLUSION: Simultaneous triple-wavelength laser device is a safe and effective hair removal modality. J Drugs Dermatol. 2020;19(5): doi:10.36849/JDD.2020.4735.


Asunto(s)
Remoción del Cabello/instrumentación , Cabello/efectos de la radiación , Láseres de Semiconductores/efectos adversos , Adulto , Estudios de Seguimiento , Cabello/diagnóstico por imagen , Remoción del Cabello/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Fotograbar , Estudios Retrospectivos , Resultado del Tratamiento
14.
J Drugs Dermatol ; 19(5): 498-503, 2020 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32484632

RESUMEN

OBJECTIVES: To evaluate long term effectiveness and safety with the use of a combined radiofrequency and optical home hair removal device in all skin types and over both facial and body areas. METHODS: A combined intense pulsed light (IPL) and radiofrequency (RF) home device was used for hair removal. Two separate study designs were evaluated. In the first design, bilateral body areas were treated with 7 weekly procedures and then unilateral areas received up to 12 monthly maintenance treatments while the corresponding other side received no further therapy. For the second design, facial areas received 4 procedures in 2 to 5 days visits, followed by 2 weekly, and then 6 biweekly procedures. All patients in both study designs had hair count evaluations up to 12 months post their last procedure. The highest energy used was 4 J/cm². RESULTS: In the first design, 58 subjects participated of which 15% were skin types V-VI. A total of 188 anatomical sites were treated. Hair reduction at 6 and 12 months post the last procedure was 56% and 52% respectively for the maintenance side and 47% and 37% for the non-maintenance side. For the second design, 19 subjects had 59 facial sites treated. Fifteen percent were skin types V –VI. The overall hair reduction at the end of receiving their procedures was 45%. At 12 months post the last procedure, the hair reduction was 42%. Aside for transient mild erythema, there were no adverse effects noted. CONCLUSIONS: Long term persistent hair reduction was achieved using an RF/IPL home-use hair reduction device. The combination of RF and optical energies allowed for the effective application of low energy usage. All skin types and both facial and body anatomical regions tolerated the procedures very well. J Drugs Dermatol. 2020;19(5):498-503. doi:10.36849/JDD.2020.4741.


Asunto(s)
Eritema/diagnóstico , Remoción del Cabello/instrumentación , Cabello/efectos de la radiación , Luz/efectos adversos , Ondas de Radio/efectos adversos , Adolescente , Adulto , Anciano , Eritema/etiología , Femenino , Estudios de Seguimiento , Cabello/diagnóstico por imagen , Remoción del Cabello/efectos adversos , Remoción del Cabello/métodos , Humanos , Masculino , Persona de Mediana Edad , Fotograbar , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
15.
Opt Lett ; 44(7): 1634-1637, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30933109

RESUMEN

All-optical photoacoustic microscopy (AOPAM) facilitates high-sensitivity, wide-bandwidth, volumetric imaging without coupling media. However, the rapid divergence of the Gaussian beam restricts the stability and depth-of-field in typical Gaussian AOPAM (G-AOPAM). Here we report an extended depth-of-field AOPAM using a dual non-diffracting Bessel beam (B-AOPAM). Benefiting from the designing, the B-AOPAM has the unique advantages of increasing depth resolving ability and improving photoacoustic detection sensitivity. The proposed scheme shows optimal lateral resolution of 2.4 µm and a long depth-of-focus of 635 µm, which is 10-fold larger than that of the G-AOPAM. The scattering phantoms and in vivo animal experiments demonstrated the imaging feasibility and capability of the B-AOPAM, which can provide noncontact, high spatial resolution imaging of non-flat tissue and contribute to future clinical applications.


Asunto(s)
Microscopía/métodos , Técnicas Fotoacústicas/métodos , Cabello/diagnóstico por imagen , Humanos , Modelos Teóricos , Distribución Normal
16.
Exp Dermatol ; 28(1): 76-79, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30417461

RESUMEN

Thioglycolate is a potent depilatory agent. In addition, it has been proposed to be useful as a penetration enhancer for transepidermal drug delivery. However, the effects on hair structure and stress responses it elicits in epidermal keratinocytes have not been fully characterised. We have used label-free confocal and fluorescence lifetime imaging supported by electron microscopy to demonstrate how thioglycolate damages hair cuticle cells by generating breakages along the endocuticle and leading to swelling of cortex cells. Maleimide staining of free SH-groups and a decrease in the average fluorescence lifetime of endogenous fluorophores demonstrate a specific change in protein structure in both hair cuticle and cortex. We found that the thioglycolate damages cornified envelopes isolated from the stratum corneum of the epidermis. However, thioglycolate-treated epidermal equivalent cultures recover within 48 hours, which highlights the reversibility of the damage. HaCaT keratinocytes respond to thioglycolate by increased proliferation, onset of differentiation and expression of the chaperone protein Hsp 70, but not Hsp 27. Up-regulation of involucrin can be blocked by an application of c-Jun N-terminal kinase (JNK) inhibitor, but the up-regulation of Hsp 70 takes place regardless of the presence of the JNK inhibitor.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Fármacos Dermatológicos/farmacología , Cabello/efectos de los fármacos , Queratinocitos/fisiología , Tioglicolatos/farmacología , Línea Celular , Femenino , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas HSP70 de Choque Térmico/metabolismo , Cabello/diagnóstico por imagen , Cabello/ultraestructura , Remoción del Cabello , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Microscopía Confocal , Microscopía Electrónica , Microscopía Fluorescente , Inhibidores de Proteínas Quinasas/farmacología , Precursores de Proteínas/antagonistas & inhibidores , Precursores de Proteínas/metabolismo
17.
Br J Dermatol ; 181(5): 1046-1051, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-30844082

RESUMEN

BACKGROUND: Specific trichoscopic signs of tinea capitis (TC) were first described in 2008. The accuracy of this diagnostic tool has not been evaluated. OBJECTIVES: To assess the diagnostic accuracy of trichoscopy. METHODS: A prospective, multicentre study was done between March 2015 and March 2017 at the dermatology departments of four French university medical centres. Patients with a presumed diagnosis of TC were included. Trichoscopy was considered to be positive if at least one specific trichoscopic sign was observed. Trichoscopy results were compared with the gold standard for diagnosis of TC (mycological culture). RESULTS: One hundred patients were included. Culture was positive for 53 patients and negative for 47. The sensitivity of trichoscopy was 94% [95% confidence interval (CI) 88-100], specificity was 83% (95% CI 72-94), positive predictive value was 92% and negative predictive value was 86%. Comma hairs, corkscrew hairs, zigzag hairs, Morse-code-like hairs and whitish sheath were significantly more frequent in patients with a positive mycological culture (P < 0·001). Comma hairs were more frequent in patients with Trichophyton TC (P = 0·026), and zigzag hairs were more frequent in patients with Microsporum TC (P < 0·001). Morse-code-like hair was not observed in any patients with Trichophyton TC and therefore appears to be highly specific for Microsporum TC. CONCLUSIONS: The presence of a single trichoscopic finding is predictive of TC. Trichoscopy is a useful, rapid, painless, highly sensitive tool for the diagnosis of TC - even for dermoscopists with little experience of trichoscopy. It enhances physicians' ability to make treatment decisions. What's already known about this topic? Tinea capitis (TC) must be confirmed by a mycological culture that may take up to 6 weeks, delaying treatment. Specific trichoscopic signs of TC were first described in 2008, but the accuracy of trichoscopy for diagnosing TC has not previously been evaluated. What does this study add? The present series is the largest yet on the use of trichoscopy in the diagnosis of TC. Our results demonstrated that the presence of a single feature (comma hair, corkscrew hair, zigzag hair, Morse-code-like hair or whitish sheath) is predictive of TC. Trichoscopy is painless and highly sensitive. Morse-code-like hair appears to be highly specific for Microsporum TC.


Asunto(s)
Dermoscopía , Cabello/diagnóstico por imagen , Microsporum/aislamiento & purificación , Tiña del Cuero Cabelludo/diagnóstico , Trichophyton/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Diagnóstico Diferencial , Estudios de Factibilidad , Femenino , Cabello/microbiología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Técnicas de Tipificación Micológica , Valor Predictivo de las Pruebas , Estudios Prospectivos , Cuero Cabelludo , Tiña del Cuero Cabelludo/microbiología , Adulto Joven
18.
J Am Acad Dermatol ; 80(3): 694-700, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30287324

RESUMEN

BACKGROUND: Promising results with platelet-rich plasma (PRP) in androgenetic alopecia that could be associated with platelet number and growth factor levels were described. OBJECTIVE: Analyze the platelet countand growth factor levels in PRP and their correlation with hair growth parameters evaluated by using the TrichoScan (Tricholog GmbH, Freiburg, Germany). METHODS: A total of 26 patients were randomized to receive 4 subcutaneous injections of PRP or saline. Hair growth, hair density, and percentage of anagen hairs were evaluated by using the TrichoScan method before injection, 15 days after the last injection, and again 3 months after the last injection. Growth factors (platelet-derived growth factor, epidermal growth factor, and vascular endothelial growth factor) were measured by the Luminex method (Millipore, Bedford, MA). RESULTS: We demonstrated a significant increase in hair count (P = .0016), hair density (P = .012) and percentage of anagen hairs (P = .007) in the PRP group versus in the control group, without correlation with platelet counts or quantification of the growth factors in PRP. LIMITATIONS: Other growth factors that could be related to response to PRP were not evaluated. CONCLUSION: Our data favor the use of PRP as a therapeutic alternative in the treatment of androgenetic alopecia. The lack of association between platelet count, platelet-derived growth factor, epidermal growth factor, and vascular endothelial growth factor levels and clinical improvement suggest that other mechanisms could be involved in this response.


Asunto(s)
Alopecia/terapia , Cabello/crecimiento & desarrollo , Péptidos y Proteínas de Señalización Intercelular/análisis , Recuento de Plaquetas , Plasma Rico en Plaquetas/química , Plasma Rico en Plaquetas/citología , Adulto , Dermoscopía , Método Doble Ciego , Factor de Crecimiento Epidérmico/análisis , Cabello/diagnóstico por imagen , Humanos , Masculino , Factor de Crecimiento Derivado de Plaquetas/análisis , Resultado del Tratamiento , Factor A de Crecimiento Endotelial Vascular/análisis , Adulto Joven
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