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1.
Dermatol Clin ; 31(1): 155-66, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23159184

RESUMEN

Primary cicatricial alopecias refer to a group of rare, idiopathic, inflammatory scalp disorders that result in permanent hair loss. Primary cicatricial alopecias comprise a diverse group of inflammatory diseases and can be classified via different approaches, such as clinical presentation, histopathologic findings, or both. Primary cicatricial alopecias are rare scalp disorders. Whiting found a prevalence of 7.3% in all patients who sought advice for hair and scalp problems at the Baylor Hair Research and Treatment Center in Dallas between 1989 and 1999.


Asunto(s)
Alopecia/clasificación , Cicatriz/clasificación , Alopecia/patología , Alopecia/terapia , Cicatriz/patología , Cicatriz/terapia , Diagnóstico Diferencial , Cabello/crecimiento & desarrollo , Humanos
2.
Dermatol Ther ; 24(3): 320-5, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21689241

RESUMEN

Of the world population, 1.7% is suffering from alopecia areata at some point in their lives. The exact etiology of this disease is still unknown, and the course of the disease is unpredictable. Effective treatments, especially for severe multifocal alopecia areata, alopecia areata totalis, and alopecia areata universalis, are lacking. The present article will discuss side effects and relapse rates of different systemic agents for treatment of severe and rapid progressive alopecia areata.


Asunto(s)
Alopecia Areata/tratamiento farmacológico , Glucocorticoides/uso terapéutico , Inmunosupresores/uso terapéutico , Adulto , Alopecia Areata/patología , Animales , Progresión de la Enfermedad , Femenino , Glucocorticoides/efectos adversos , Glucocorticoides/farmacología , Humanos , Inmunosupresores/efectos adversos , Inmunosupresores/farmacología , Masculino , Persona de Mediana Edad , Recurrencia , Índice de Severidad de la Enfermedad
3.
Br J Clin Pharmacol ; 72(5): 768-74, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21599723

RESUMEN

AIMS: The aim of this study was to define the underlying relative penetration of caffeine through hair follicles and through intact stratum corneum with time in vivo through pharmacokinetic modelling. METHODS: Caffeine plasma concentration-time profiles after topical application into skin with or without hair follicle blocking were modelled using the Wagner-Nelson method or a compartmental model with first order absorption and elimination. Pharmacokinetic parameters describing absorption rate and extent of absorption through hair follicles or the stratum corneum were determined separately and compared with each other. RESULTS: The obtained pharmacokinetic parameters from the two methods were similar. The absorption rate constant of caffeine for hair follicles was nearly 10 times higher than that for the stratum corneum and the percentage of absorption from hair follicles was more than half of that of the stratum corneum. In addition, the absorption from the stratum corneum showed an approximately 10 min delay while there was no delay for absorption from hair follicles. All caffeine absorbed by hair follicles occurs within 30 min of application and accounts for 10.5 to 33.8% of the total amount absorbed across the skin for all subjects, whereas absorption of caffeine through the stratum corneum can occur over several hours. CONCLUSION: Hair follicles contribute significantly to percutaneous absorption of caffeine after topical application in man in vivo only at times soon after application.


Asunto(s)
Cafeína/farmacocinética , Estimulantes del Sistema Nervioso Central/farmacocinética , Folículo Piloso/metabolismo , Absorción Cutánea/fisiología , Piel/metabolismo , Solventes/metabolismo , Administración Tópica , Humanos , Masculino , Modelos Teóricos , Factores de Tiempo
4.
Br J Clin Pharmacol ; 68(2): 181-6, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19694736

RESUMEN

AIMS: Due to ethical reasons, in vivo penetration studies are not applicable at all stages of development of new substances. Therefore, the development of appropriate in vitro methods is essential, as well as the comparison of the obtained in vivo and in vitro data, in order to identify their transferability. The aim of the present study was to investigate the follicular penetration of caffeine in vitro and to compare the data with the in vivo results determined previously under similar conditions. METHODS: The Follicular Closing Technique (FCT) represents a method to investigate the follicular penetration selectively. In the present study, FCT was combined with the Franz diffusion cell in order to differentiate between follicular and intercellular penetration of caffeine into the receptor medium in vitro. Subsequently, the results were compared with the data obtained in an earlier study investigating follicular and intercellular penetration of caffeine in vivo. RESULTS: The comparison of the data revealed that the in vitro experiments were valuable for the investigation of the follicular penetration pathway, which contributed in vivo as well as in vitro to approximately 50% of the total penetration, whereas the kinetics of caffeine penetration were shown to be significantly different. CONCLUSIONS: The combination of FCT with the Franz diffusion cell represents a valuable method to investigate follicular penetration in vitro. Nevertheless, in vivo experiments should not be abandoned as in vitro, structural changes of skin occur and blood flow and metabolism are absent, probably accounting for reduced penetration rates in vitro.


Asunto(s)
Cafeína/farmacocinética , Folículo Piloso/metabolismo , Administración Cutánea , Adulto , Cromatografía Líquida de Alta Presión , Femenino , Folículo Piloso/efectos de los fármacos , Humanos , Persona de Mediana Edad , Modelos Biológicos , Permeabilidad/efectos de los fármacos , Absorción Cutánea/fisiología
7.
J Am Acad Dermatol ; 61(3): 512-5, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19700017

RESUMEN

Uncombable hair syndrome is a relatively rare anomaly of the hair shaft, with less than 100 cases reported to date, that results in a disorganized, unruly hair pattern that is impossible to comb flat. The characteristic longitudinal grooves along the hair shaft, along with the triangular or kidney-shaped cross section allows this condition to be diagnosed microscopically. The majority of cases are inherited in an autosomal-dominant manner with either complete or incomplete penetrance. There is no definitive treatment, and most cases improve with the onset of puberty.


Asunto(s)
Displasia Ectodérmica/genética , Displasia Ectodérmica/patología , Enfermedades del Cabello/patología , Cabello/patología , Adolescente , Niño , Preescolar , Femenino , Genes Dominantes , Cabello/ultraestructura , Enfermedades del Cabello/genética , Preparaciones para el Cabello , Humanos , Microscopía Electrónica
9.
J Biomed Opt ; 14(2): 021001, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19405714

RESUMEN

Liposomes in the nanosize range have been recognized as a versatile drug delivery system of both hydrophilic and lipophilic molecules. In order to develop a liposome-based topical vaccination strategy, five different types of liposomes were tested as a putative vaccine delivery system on pig ear skin. The investigated liposomes mainly varied in size, lipid composition, and surface charge. Using hydrophilic and hydrophobic fluorescent dyes as model drugs, penetration behavior was studied by means of confocal laser scanning microscopy of intact skin and histological sections, respectively. Follicular penetration of the liposomes was measured in comparison to a standard, nonliposomal formulation at different time points. Dependent on time but independent of their different characters, the liposomes showed a significantly higher penetration depth into the hair follicles compared to the standard formulation. The standard formulation reached a relative penetration depth of 30% of the full hair follicle length after seven days, whereas amphoteric and cationic liposomes had reached approximately 70%. Penetration depth of negatively charged liposomes did not exceed 50% of the total follicle length. The fluorescence dyes were mainly detected in the hair follicle; only a small amount of dye was found in the upper parts of the epidermis.


Asunto(s)
Portadores de Fármacos/química , Liposomas/química , Nanomedicina/métodos , Nanopartículas/administración & dosificación , Nanopartículas/química , Absorción Cutánea/fisiología , Vacunas/administración & dosificación , Administración Tópica , Animales , Diseño de Fármacos , Técnicas In Vitro , Ensayo de Materiales , Nanopartículas/ultraestructura , Tamaño de la Partícula , Porcinos
11.
Dermatol Ther ; 21(4): 238-44, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18715292

RESUMEN

Folliculitis decalvans is a rare inflammatory scalp disorder. The present paper gives a practical approach to diagnosis and patient management and reviews possible pathogenetic factors and treatment options. Folliculitis decalvans is classified as primary neutrophilic cicatricial alopecia and predominantly occurs in middle-aged adults. Staphylococcus aureus and a deficient host immune response seem to play an important role in the development of this disfiguring scalp disease. Lesions occur mainly in the vertex and occipital area. Clinically, the lesions present with follicular pustules, lack of ostia, diffuse and perifollicular erythema, follicular tufting, and, oftentimes, hemorrhagic crusts and erosions. Histology displays a mainly neutrophilic inflammatory infiltrate in early lesions and additionally lymphocytes and plasma cells in advanced lesions. Treatment is focused on the eradication of S. aureus anti-inflammatory agents.


Asunto(s)
Foliculitis/tratamiento farmacológico , Diagnóstico Diferencial , Foliculitis/diagnóstico , Foliculitis/etiología , Humanos
12.
Dermatol Ther ; 21(4): 279-94, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18715298

RESUMEN

Various nonfollicular scalp conditions can cause secondary scarring or permanent alopecia. Possible causes are congenital defects, trauma, inflammatory conditions, infections, and neoplasms (rarely drugs). Associated signs and symptoms and other diagnostic procedures such as histopathology may aid in the diagnosis. Detection of the underlying disorder may be difficult in end-stage lesions. Treatment is specific for active conditions. Surgery and hair transplantation are options for localized scars.


Asunto(s)
Alopecia/etiología , Cicatriz/etiología , Alopecia/diagnóstico , Alopecia/patología , Cicatriz/diagnóstico , Cicatriz/patología , Humanos
13.
Dermatol Ther ; 21(4): 249-56, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18715294

RESUMEN

Lichen planopilaris is a chronic scarring alopecia characterized by follicular hyperkeratosis, perifollicular erythema, and loss of follicular orifices. The scalp lesions may be single or multiple and commonly involve the vertex and parietal area. The hair follicles at the margin of the alopecic patches reveal perifollicular erythema. Anagen hairs can be pulled out easily in active lesions. Associated cutaneous, nail, and mucous membrane lichen planus may be present. Commonly encountered symptoms and signs are increased hair shedding, itching, scaling, burning, and tenderness. Differentiation from other cicatricial alopecia can be performed through meticulous evaluation of the clinical, histopathologic, and immunohistopathologic findings. Treatment strategies depend on the disease activity and physician expertise. Although there are no definitive curative modalities, some new discoveries and conceptual advances continue to broaden our treatment options of this complex condition.


Asunto(s)
Alopecia/tratamiento farmacológico , Cicatriz/tratamiento farmacológico , Liquen Plano/tratamiento farmacológico , Alopecia/diagnóstico , Alopecia/etiología , Alopecia/patología , Cicatriz/diagnóstico , Cicatriz/etiología , Cicatriz/patología , Diagnóstico Diferencial , Humanos , Liquen Plano/diagnóstico , Liquen Plano/etiología , Liquen Plano/patología
14.
Dermatol Ther ; 21(4): 257-63, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18715295

RESUMEN

Pseudopelade of Brocq (PPB) is a rare, idiopathic, slowly progressive hair disorder, resulting in cicatricial alopecia. It typically presents in Caucasian adult patients as small, smooth, flesh-toned and slightly depressed alopecic patches with irregular outlines. It primarily involves the parietal and vertex portions of the scalp with a chronic prolonged course. Controversial opinions still exist as to whether PPB is a single entity or an end stage of several cicatricial alopecic disorders. A practical approach to diagnosis of PPB and therapeutic update are discussed in this review.


Asunto(s)
Alopecia/patología , Cicatriz/patología , Alopecia/tratamiento farmacológico , Alopecia/etiología , Cicatriz/tratamiento farmacológico , Cicatriz/etiología , Diagnóstico Diferencial , Humanos
15.
J Biomed Opt ; 13(1): 014003, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18315361

RESUMEN

Excisional biopsies and routine histology remains the gold standard for the histomorphologic evaluation of normal and diseased skin. However, there is increasing interest in the development of noninvasive optical technologies for evaluation, diagnosis, and monitoring of skin disease in vivo. Fluorescent confocal microscopy is an innovative optical technology that has previously been used for morphologic evaluation of live human tissue. We evaluate the clinical applicability of a fluorescent confocal laser scanning microscope (FLSM) for a systematic evaluation of normal and diseased skin in vivo and in correlation with routine histology. A total of 40 patients were recruited to participate in the study. Skin sites of 10 participants with no prior history of skin disease served as controls and to evaluate topographic variations of normal skin in vivo. Thirty patients with a suspected diagnosis of nonmelanoma skin cancer were evaluated, whereby FLSM features of actinic keratoses (AK) and basal cell carcinoma (BCC) were recorded in an observational analysis. Selected BCCs were monitored for their skin response to topical therapy using Imiquimod as an immune-response modifier. A commercially available fluorescence microscope (OptiScan Ltd., Melbourne, Australia) was used to carry out all FLSM evaluations. Common FLSM features to AK and BCC included nuclear pleomorphism at the level of the granular and spinous layer and increased vascularity in the superficial dermal compartment. Even though the presence of superficial disruption and mere atypia of epidermal keratinocytes was more indicative of AK, the nesting of atypical basal cells, increased blood vessel tortuosity, and nuclear polarization were more typical for BCC. All diagnoses were confirmed by histology. FLSM allowed a monitoring of the local immune response following therapy with Imiquimod and demonstrated a continuous normalization of diseased skin on repeated evaluations over time. This study illustrates potential applications of FLSM in clinical dermatology for the evaluation of dynamic skin conditions and monitoring of cutaneous response to noninvasive therapies. The findings are of preliminary nature and warrant further investigations in the future.


Asunto(s)
Dermoscopía/métodos , Melanoma/patología , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Neoplasias Cutáneas/patología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Skinmed ; 7(2): 78-83, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18326998

RESUMEN

The second part of this 2-part article reviews clinical features, histology, management, and treatment of neutrophilic primary cicatricial alopecias (folliculitis decalvans and dissecting folliculitis) and mixed primary cicatricial alopecias (acne keloidalis, acne necrotica, and erosive pustular dermatosis).


Asunto(s)
Alopecia/diagnóstico , Alopecia/tratamiento farmacológico , Humanos
17.
Skinmed ; 7(1): 19-26, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18174797

RESUMEN

In this 2-part article, the authors review the primary cicatricial alopecias. Primary cicatricial alopecia can be defined as predominantly lymphocytic, neutrophilic, or mixed based on the nature of the follicular infiltrate that is present around affected hair follicles. Lymphocytic primary cicatricial alopecias include chronic cutaneous lupus erythematosus (discoid lupus erythematosus), lichen planopilaris, classic pseudopelade of Brocq, central centrifugal cicatricial alopecia, alopecia mucinosa, and keratosis follicularis spinulosa decalvans. In this first part, the authors summarize the classification, epidemiology, diagnostic approach, and patient management of lymphocytic cicatricial alopecias. In part II, the authors will focus on neutrophilic cicatricial alopecias and mixed cicatricial alopecias.


Asunto(s)
Alopecia/diagnóstico , Alopecia/tratamiento farmacológico , Alopecia/clasificación , Alopecia/etiología , Humanos , Cuero Cabelludo/patología
18.
Br J Clin Pharmacol ; 65(4): 488-92, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18070215

RESUMEN

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: * In recent years, it has been suggested that hair follicles represent important shunt routes into the skin for drugs and chemicals [1-3]. * In vitro studies have shown the importance of skin appendages for skin penetration by hydrophilic compounds [4]. Investigation of follicular penetration in vivo has been difficult due to the absence of appropriate analytical methods or suitable animal model systems. * Recently, a new method was described that quantifies follicular penetration in vivo by using selective closure of hair follicles [5]. * Caffeine is frequently used in skin penetration experiments as a model for highly water-soluble compounds. Occlusion [6] and skin thickness [7] seem to have little influence on the penetration of caffeine. However, percutaneous absorption rates for caffeine exhibit regional skin differences in humans in vivo[1]. WHAT THIS STUDY ADDS: * The results of the present study demonstrate that a fast drug delivery of caffeine occurs through shunt routes. Therefore, hair follicles are considerable weak spots in our protective sheath against penetration into the body by hydrophilic substances. * We showed that there is a quantitative distinction between follicular penetration and interfollicular diffusion of caffeine in vivo. * These findings are of importance for the development and optimization of topically applied drugs and cosmetics. In addition, such properties must be considered in the development of skin protection measures. AIMS: The skin and its appendages are our protective shield against the environment and are necessary for the maintenance of homeostasis. Hypotheses concerning the penetration of substances into the skin have assumed diffusion through the lipid domains of the stratum corneum. It is believed that while hair follicles represent a weakness in the shield, they play a subordinate role in the percutaneous penetration processes. Previous investigation of follicular penetration has mostly addressed methodical and technical problems. Our study utilized a selective closure technique of hair follicle orifices in vivo, for the comparison of interfollicular and follicular absorption rates of caffeine in humans. METHODS: Every single hair follicle within a delimited area of skin was blocked with a microdrop of a special varnish-wax-mixture in vivo. Caffeine in solution was topically applied and transcutaneous absorption into the blood was measured by a new surface ionization mass spectrometry (SI/MS) technique, which enabled a clear distinction to be made between interfollicular and follicular penetration of a topically applied substance. RESULTS: Caffeine (3.75 ng ml(-1)) was detected in blood samples, 5 min after topical application, when the follicles remained open. When the follicles were blocked, caffeine was detectable after 20 min (2.45 ng ml(-1)). Highest values (11.75 ng caffeine ml(-1)) were found 1 h after application when the follicles were open. CONCLUSIONS: Our findings demonstrate that hair follicles are considerable weak spots in our protective sheath against certain hydrophilic drugs and may allow a fast delivery of topically applied substances.


Asunto(s)
Cafeína/farmacocinética , Estimulantes del Sistema Nervioso Central/farmacocinética , Folículo Piloso/metabolismo , Absorción Cutánea/efectos de los fármacos , Administración Cutánea , Adulto , Cafeína/administración & dosificación , Cafeína/sangre , Estimulantes del Sistema Nervioso Central/administración & dosificación , Estimulantes del Sistema Nervioso Central/sangre , Sistemas de Liberación de Medicamentos , Folículo Piloso/efectos de los fármacos , Humanos , Masculino , Absorción Cutánea/fisiología , Resultado del Tratamiento
19.
Ger Med Sci ; 6: Doc08, 2008 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-19675735

RESUMEN

BACKGROUND: Water-filtered infrared-A (wIRA) irradiation has been shown to enhance penetration of clinically used topically applied substances in humans through investigation of functional effects of penetrated substances like vasoconstriction by cortisone. AIM OF THE STUDY: Investigation of the influence of wIRA irradiation on the dermatopharmacokinetics of topically applied substances by use of optical methods, especially to localize penetrating substances, in a prospective randomised controlled study in humans. METHODS: The penetration profiles of the hydrophilic dye fluorescein and the lipophilic dye curcumin in separate standard water-in-oil emulsions were determined on the inner forearm of test persons by tape stripping in combination with spectroscopic measurements. Additionally, the penetration was investigated in vivo by laser scanning microscopy. Transepidermal water loss, hydration of the epidermis, and surface temperature were determined. Three different procedures (modes A, B, C) were used in a randomised order on three separate days of investigation in each of 12 test persons. In mode A, the two dyes were applied on different skin areas without water-filtered infrared-A (wIRA) irradiation. In mode B, the skin surface was irradiated with wIRA over 30 min before application of the two dyes (Hydrosun radiator type 501, 10 mm water cuvette, orange filter OG590, water-filtered spectrum: 590-1400 nm with dominant amount of wIRA). In mode C, the two dyes were applied and immediately afterwards the skin was irradiated with wIRA over 30 min. In all modes, tape stripping started 30 min after application of the formulations. Main variable of interest was the ratio of the amount of the dye in the deeper (second) 10% of the stratum corneum to the amount of the dye in the upper 10% of the stratum corneum. RESULTS: The penetration profiles of the hydrophilic fluorescein showed in case of pretreatment or treatment with wIRA (modes B and C) an increased penetration depth compared to the non-irradiated skin (mode A): The ratio of the amount of the dye in the deeper (second) 10% of the stratum corneum to the amount of the dye in the upper 10% of the stratum corneum showed medians and interquartile ranges for mode A of 0.017 (0.007/0.050), for mode B of 0.084 (0.021/0.106), for mode C of 0.104 (0.069/0.192) (difference between modes: p=0.0112, significant; comparison mode A with mode C: p<0.01, significant). In contrast to fluorescein, the lipophilic curcumin showed no differences in the penetration kinetics, in reference to whether the skin was irradiated with wIRA or not. These effects were confirmed by laser scanning microscopy. Water-filtered infrared-A irradiation increased the hydration of the stratum corneum: transepidermal water loss rose from approximately 8.8 g m(-2) h(-1) before wIRA irradiation to 14.2 g m(-2) h(-1) after wIRA irradiation and skin hydration rose from 67 to 87 relative units. Skin surface temperature increased from 32.8 degrees C before wIRA to 36.4 degrees C after wIRA irradiation. DISCUSSION: The better penetration of the hydrophilic dye fluorescein after or during skin irradiation (modes B and C) can be explained by increased hydration of the stratum corneum by irradiation with wIRA. CONCLUSIONS: As most topically applied substances for the treatment of patients are mainly hydrophilic, wIRA can be used to improve the penetration of substances before or after application of substances - in the first case even of thermolabile substances - with a broad clinical relevance as a contact free alternative to an occlusive dressing.

20.
Endocrinol Metab Clin North Am ; 36(2): 379-98, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17543725

RESUMEN

Androgenetic alopecia (AGA), or male pattern hair loss, affects approximately 50% of the male population. AGA is an androgen-related condition in genetically predisposed individuals. There is no treatment to completely reverse AGA in advanced stages, but with medical treatment (eg, finasteride, minoxidil, or a combination of both), the progression can be arrested and partly reversed in the majority of patients who have mild to moderate AGA. Combination with hair restoration surgery leads to best results in suitable candidates. Physicians who specialize in male health issues should be familiar with this common condition and all the available approved treatment options.


Asunto(s)
Alopecia/etiología , Andrógenos/fisiología , Alopecia/diagnóstico , Alopecia/epidemiología , Alopecia/terapia , Comorbilidad , Finasterida/uso terapéutico , Humanos , Masculino , Minoxidil/uso terapéutico , Modelos Biológicos , Prevalencia , Factores de Riesgo , Cirugía Plástica
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