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1.
Br J Dermatol ; 160(3): 482-501, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19183169

RESUMEN

Primary cicatricial alopecias (PCAs) are a rare, but important, group of disorders that cause irreversible damage to hair follicles resulting in scarring and permanent hair loss. They may also signify an underlying systemic disease. Thus, it is of paramount importance that clinicians who manage patients with hair loss are able to diagnose these disorders accurately. Unfortunately, PCAs are notoriously difficult conditions to diagnose and treat. The aim of this review is to present a rational and pragmatic guide to help clinicians in the professional assessment, investigation and diagnosis of patients with PCA. Illustrating typical clinical and histopathological presentations of key PCA entities we show how dermatoscopy can be profitably used for clinical diagnosis. Further, we advocate the search for loss of follicular ostia as a clinical hallmark of PCA, and suggest pragmatic strategies that allow rapid formulation of a working diagnosis.


Asunto(s)
Alopecia/diagnóstico , Cicatriz/diagnóstico , Algoritmos , Alopecia/complicaciones , Alopecia/patología , Biopsia , Cicatriz/etiología , Cicatriz/patología , Diagnóstico Diferencial , Folículo Piloso/patología , Humanos
2.
Br J Dermatol ; 159(1): 1-22, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18489608

RESUMEN

Primary cicatricial alopecias (PCAs) are a poorly understood group of disorders that result in permanent hair loss. Clinically, they are characterized not only by permanent loss of hair shafts but also of visible follicular ostia along with other visible changes in skin surface morphology, while their histopathological hallmark usually (although not always) is the replacement of follicular structures with scar-like fibrous tissue. As hair follicle neogenesis in adult human scalp skin is not yet a readily available treatment option for patients with cicatricial alopecias, the aim of treatment, currently, remains to reduce symptoms and to slow or stop PCA progression, namely the scarring process. Early treatment is the key to minimizing the extent of permanent alopecia. However, inconsistent terminology, poorly defined clinical end-points and a lack of good quality clinical trials have long made management of these conditions very challenging. As one important step towards improving the management of this under-investigated and under-serviced group of dermatoses, the current review presents evidence-based guidance for treatment, with identification of the strength of evidence, and a brief overview of clinical features of each condition. Wherever only insufficient evidence-based advice on PCA management can be given at present, this is indicated so as to highlight important gaps in our clinical knowledge that call for concerted efforts to close these in the near future.


Asunto(s)
Alopecia/terapia , Cicatriz/terapia , Erupciones Acneiformes/complicaciones , Erupciones Acneiformes/terapia , Alopecia/diagnóstico , Antibacterianos/uso terapéutico , Cicatriz/diagnóstico , Enfermedad de Darier/complicaciones , Enfermedad de Darier/terapia , Medicina Basada en la Evidencia , Folículo Piloso/trasplante , Humanos , Lupus Eritematoso Discoide/complicaciones , Lupus Eritematoso Discoide/terapia , Enfermedades Cutáneas Vesiculoampollosas/complicaciones , Enfermedades Cutáneas Vesiculoampollosas/terapia
3.
Dermatol Ther ; 21(4): 264-7, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18715296

RESUMEN

Central centrifugal cicatricial alopecia (CCCA) is a common but poorly understood cause of hair loss in African American women. A photographic scale was developed that captures the pattern and severity of the central hair loss seen with CCCA in order to help identify this problem in the general community and to potentially correlate clinical data with hair loss. The utility and reproducibility of this photographic scale was determined in a group of 150 African American women gathered for a health and beauty day who were evaluated by both four investigators experienced in the diagnosis of hair disorders and by the subjects themselves.


Asunto(s)
Alopecia/patología , Negro o Afroamericano , Femenino , Humanos , Fotograbar
4.
FEBS Lett ; 468(2-3): 243-6, 2000 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-10692595

RESUMEN

Epithiospecifier protein (ESP), a ferrous ion dependent protein, has a potential role in regulating the release of elemental sulphur, nitriles, isothiocyanates and cyanoepithioalkanes from glucosinolates. Two classes of ESP polypeptides were purified with molecular masses of 39 and 35 kDa, and we show that the previously reported instability was conditionally dependent. The 39 kDa polypeptide was made up of two distinct isozymes (5.00, 5.14) whilst several were present for the 35 kDa form of ESP (5.40-5.66). An anti-ESP antibody reacted with both the 39 and 35 kDa ESP forms in Brassica napus and strongly with a polypeptide corresponding to the 35 kDa ESP form in Crambe abyssinica, but did not detect any ESP in Sinapis alba or Raphanus sativus. A cytochrome P-450 mediated iron dependent epoxidation type mechanism is suggested for ESP.


Asunto(s)
Brassica/metabolismo , Glucosinolatos/metabolismo , Oximas/metabolismo , Proteínas de Plantas/metabolismo , Cromatografía en Gel , Cromatografía por Intercambio Iónico , Isoenzimas/química , Isoenzimas/aislamiento & purificación , Isoenzimas/metabolismo , Peso Molecular , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Especificidad por Sustrato , Azufre/metabolismo
5.
Arch Dermatol ; 128(11): 1486-9, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1444502

RESUMEN

BACKGROUND AND DESIGN: Intralesional recombinant interferon alfa-2b has been shown to be effective in the treatment of actinic keratoses and basal cell carcinomas. This open-label study was designed to evaluate the effectiveness and cosmetic result of this therapy on actinically induced, primary cutaneous squamous cell carcinomas. Thirty-six squamous cell carcinomas (28 invasive lesions and 8 in situ lesions) ranging in size from 0.5 to 2.0 cm in the longest dimension were treated with interferon alfa-2b 1.5 million units injected intralesionally three times per week for 3 weeks. Eighteen weeks following therapy, the treatment sites were excised and examined for histologic evidence of remaining tumor. RESULTS: Thirty-three (97.1%) of 34 evaluable lesions revealed an absence of squamous cell carcinoma histologically after therapy, although three biopsy specimens (8.8%) obtained after treatment showed actinic keratoses, for an overall complete response rate of 88.2%. The lesion not eliminated after treatment was an invasive squamous cell carcinoma. The investigators and patients independently judged 93.9% of cases to have a very good or excellent cosmetic result. Adverse reactions were limited to those influenzalike symptoms well recognized to occur with interferon therapy and these were well tolerated. Only one patient discontinued therapy due to side effects. CONCLUSIONS: This trial demonstrates that intralesional interferon is effective in the treatment of small sun-induced squamous cell carcinomas with well-tolerated side effects and a highly acceptable cosmetic result.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Interferón-alfa/uso terapéutico , Neoplasias Cutáneas/terapia , Adulto , Anciano , Carcinoma in Situ/patología , Carcinoma in Situ/terapia , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Estética , Femenino , Fibroma/patología , Fibroma/terapia , Humanos , Inyecciones Intralesiones , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Interferón-alfa/efectos adversos , Queratosis/patología , Queratosis/terapia , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Proteínas Recombinantes , Inducción de Remisión , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/cirugía
6.
Arch Dermatol ; 117(8): 482-5, 1981 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6455095

RESUMEN

Eleven institutions participated in an eight-week controlled clinical study to evaluate treatment of acne vulgaris with topical clindamycin hydrochloride and clindamycin phosphate. Three hundred fifty-eight patients with comparable baseline pustule, papule, and nodule counts applied 1%, clindamycin hydrochloride, 1% clindamycin phosphate, or a hydroalcoholic vehicle twice daily. Every two weeks, lesions were counted, and patients' evaluations of their acne conditions were scored. By week 8, pustule and papule counts in the groups who were receiving clindamycin were significantly lower than those in the group receiving placebo. Also, more patients who were receiving clindamycin thought their acne improved by week 8 (with significantly higher change-in-acne scores) than did the patients receiving placebo. Patients receiving clindamycin reported 12 episodes of diarrhea; only one episode was considered to be treatment related. These results substantiate the clinical impression that topical clindamycin is effective treatment for acne.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Clindamicina/análogos & derivados , Clindamicina/administración & dosificación , 1-Propanol/administración & dosificación , Administración Tópica , Adolescente , Adulto , Niño , Ensayos Clínicos como Asunto , Método Doble Ciego , Femenino , Humanos , Masculino , Compuestos Organofosforados/administración & dosificación , Placebos , Propilenglicol , Glicoles de Propileno/administración & dosificación , Distribución Aleatoria
7.
Dermatol Clin ; 14(4): 723-31, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9238330

RESUMEN

Chronic telogen effluvium is not uncommon. It is a form of diffuse hair loss affecting the entire scalp for which no obvious cause can be found. It usually affects women of 30 to 60 years of age who generally have a full head of hair prior to the onset of shedding. The onset is usually abrupt, with or without a recognizable initiating factor. The degree of shedding is usually severe in the early stages and the hair may come out in handfuls. Chronic telogen effluvium has distinctive clinical and histologic features that are usually diagnostic. Chronic telogen effluvium contrasts with classic acute telogen effluvium by its persistence and its tendency to fluctuate for a period of years. Patients are particularly troubled by the continuing hair loss and fear total baldness. Repeated reassurance that the condition represents shedding rather than actual hair loss and does not cause complete baldness is necessary. Chronic telogen effluvium does appear to be self-limiting in the long run.


Asunto(s)
Alopecia/diagnóstico , Adulto , Alopecia/etiología , Alopecia/terapia , Enfermedad Crónica , Femenino , Humanos
8.
Eur J Dermatol ; 11(4): 332-4, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11399540

RESUMEN

Finasteride is a type 2 5a-reductase inhibitor and therefore mimics the biochemical profile of inherited type 2 5a-reductase deficiency in men. It was developed to grow hair in androgenetic alopecia and shrink benign prostatic hyperplasia. Various clinical trials of finasteride have confirmed its beneficial effects in androgenetic alopecia in males, but not in females. It can produce visible hair growth in up to 66% of men with mild to moderate alopecia, but importantly can stop hair loss in 91% of patients. In long-term finasteride studies, placebo patients were characterized by significant and progressive hair loss. It can be concluded that finasteride prevents further hair loss by actually continuing to grow enough hair to preserve scalp coverage. This is confirmed by the loss of hair following withdrawal of finasteride in such cases. The proven preservative effect of finasteride, in addition to its restorative effect, is a strong indication for prescribing it in early cases of androgenetic alopecia before much hair has been lost.


Asunto(s)
Inhibidores de 5-alfa-Reductasa , Alopecia/tratamiento farmacológico , Finasterida/uso terapéutico , Ensayos Clínicos como Asunto , Inhibidores Enzimáticos/uso terapéutico , Humanos
9.
J Pharm Pharmacol ; 45(3): 166-70, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8097772

RESUMEN

The interaction of glutathione (GSH) with coumarin, or one of a series of compounds related to coumarin, was assessed in the absence and presence of liver microsomes (direct reaction and indirect reaction, respectively) to determine the structural requirements for direct and mono-oxygenase-mediated reaction of cyclic alpha,beta-unsaturated carbonyls with GSH. Acrolein was used as a positive control for the direct reaction, and produced complete or nearly complete depletion of GSH under all assay conditions. 5,6-Dihydro-2H-pyran-2-one and 2-cyclohexen-1-one also produced substantial depletion of GSH in the direct reaction, which was not increased by the addition of liver microsomes. Coumarin, 2H-pyran-2-one and precocene I (a substituted pyran lacking the 2-one structure) were not substrates for the direct reaction but did cause depletion of GSH when incubated in the presence of rat or human liver microsomes. These depletions were dependent on a functioning mono-oxygenase system as judged by the effects of omission of cofactors, addition of competitive or inactivating inhibitors of cytochrome P450, and induction. Dihydrocoumarin, delta-valerolactone, cyclohexanone and 4H-pyran-4-one were not substrates for either the direct or indirect reaction. These findings are rationalized on the basis of a direct nucleophilic attack of GSH on the alpha,beta-centre of the alpha,beta-unsaturated carbonyl compounds, which is hindered by benzenoid resonance in coumarin and 2H-pyran-2-one, for which enzyme-mediated reaction with GSH, probably via a 3,4-epoxide, is the favoured mechanism.


Asunto(s)
Cumarinas/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Glutatión/metabolismo , Anciano , Animales , Cumarinas/química , Sistema Enzimático del Citocromo P-450/química , Femenino , Glutatión/química , Humanos , Técnicas In Vitro , Hígado/enzimología , Hígado/metabolismo , Masculino , Metirapona/farmacología , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , Microsomas Hepáticos/metabolismo , Ratas , Ratas Wistar
10.
Cutis ; 40(3): 247-50, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3308336

RESUMEN

Alopecia areata has an unpredictable course that is not easily altered by treatment. Different treatments will provoke regrowth of terminal hair to a variable extent but may not prevent further hair loss. Corticosteroids are the most popular form of treatment and can be given topically, intralesionally, or, in rare cases, systemically; they work best by intralesional injection of long-acting steroid suspensions. Minoxidil has had limited success in stimulating hair regrowth without altering the course of alopecia areata. Short-contact anthralin therapy has also showed promise, especially in children. Other forms of treatment described herein include contact sensitizers, phototherapy, and immunomodulators such as inosiplex, cyclosporine, and nitrogen mustard.


Asunto(s)
Alopecia Areata/terapia , Humanos
11.
J Forensic Sci ; 46(4): 844-53, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11451065

RESUMEN

Analysis of mitochondrial DNA (mtDNA) sequence from human hairs has proven to be a valuable complement to traditional hair comparison microscopy in forensic cases when nuclear DNA typing is not possible. However, while much is known about the specialties of hair biology and mtDNA sequence analysis, there has been little correlation of individual information. Hair microscopy and hair embryogenesis are subjects that are sometimes unfamiliar to the forensic DNA scientist. The continual growth and replacement of human hairs involves complex cellular transformation and regeneration events. In turn, the analysis of mtDNA sequence data can involve complex questions of interpretation (e.g., heteroplasmy and the sequence variation it may cause within an individual, or between related individuals. In this paper we review the details of hair developmental histology, including the migration of mitochondria in the growing hair, and the related interpretation issues regarding the analysis of mtDNA data in hair. Macroscopic and microscopic hair specimen classifications are provided as a possible guide to help forensic scientists better associate mtDNA sequence heteroplasmy data with the physical characteristics of a hair. These same hair specimen classifications may also be useful when evaluating the relative success in sequencing different types and/or forms of human hairs. The ultimate goal of this review is to bring the hair microscopist and forensic DNA scientist closer together, as the use of mtDNA sequence analysis continues to expand.


Asunto(s)
Dermatoglifia del ADN , ADN Mitocondrial/genética , Cabello/química , Cabello/crecimiento & desarrollo , Diferenciación Celular , Medicina Legal/métodos , Cabello/ultraestructura , Humanos , Pigmentación
17.
Br J Dermatol ; 157(5): 1013-6, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17714535

RESUMEN

Recent articles on hair follicle stem cells have summarized the current state of knowledge of what has been termed the hair follicle 'bulge'. During the course of immunohistological studies aimed at characterizing the expression of selected extracellular matrix proteins in the - as yet insufficiently characterized - niche of human bulge hair follicle stem cells, we have recently come across a largely forgotten, peculiar epithelial protrusion of the outer root sheath, which was visible in only a minority of all examined hair follicles. The morphology and immunoreactivity patterns of this structure, the 'follicular trochanter', are described herein.


Asunto(s)
Folículo Piloso/citología , Proteínas de la Matriz Extracelular/biosíntesis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuero Cabelludo , Células Madre , Terminología como Asunto
18.
West J Med ; 131(6): 551-7, 1979 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-161830

RESUMEN

The cause of acne is still obscure, but genetic predisposition, sebaceous overactivity, overgrowth of bacterial flora and exposure to comedogenic substances are all significant factors. Acne lesions occur mainly in sebaceous follicles, which are characterized by deep follicular canals and large sebaceous glands. The associated seborrhea is not due to a circulatory excess of androgens but may be caused by a local amplification of androgenic activity. This, in turn, may be due to large numbers of androgen receptors and a high concentration of enzymes such as 17beta-hydroxysteroid dehydrogenase, within the sebaceous gland itself. Hyperkeratosis of the retention type in the pilary infrainfundibulum obstructs the outflow of sebum and keratin flakes. This favors the proliferation of Propionibacterium acnes which may initiate inflammation in microcomedos and lead to formation of pustules, papules or nodules. Topical therapy with tretinoin, benzoyl peroxide and antibiotics such as clindamycin is widely used today. Oral tetracyclines and other chemotherapeutic agents remain necessary in severe cases.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Acné Vulgar/clasificación , Acné Vulgar/etiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Vitamina A/uso terapéutico
19.
J Am Acad Dermatol ; 16(1 Pt 1): 1-25, 1987 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3805378

RESUMEN

Abnormalities of the hair shaft are varied and often confusing. They do require accurate recognition, which can be helpful in the diagnosis and management of a hair disorder, or in the detection of underlying disease. A reliable evaluation of hair shaft abnormality is dependent on familiarity with the vast structural variations in normal hair, the hair growth cycle, and the changes produced by weathering. These structural abnormalities can be congenital or acquired, and some are associated with hair fragility. The classification used here has the advantage of simplicity and is keyed to easy recognition of the abnormalities under the light microscope. The four major types of abnormality are fractures, irregularities, twisting, and extraneous matter affecting the hair shaft. The diagnostic features of the different hair shaft abnormalities are outlined.


Asunto(s)
Enfermedades del Cabello/patología , Cabello/anomalías , Infecciones por Corynebacterium/diagnóstico , Cabello/ultraestructura , Humanos , Infestaciones por Piojos/diagnóstico , Microscopía Electrónica de Rastreo , Piedra/diagnóstico , Cuero Cabelludo , Tiña del Cuero Cabelludo/diagnóstico
20.
J Am Acad Dermatol ; 45(3 Suppl): S81-6, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11511857

RESUMEN

In androgenetic alopecia, or pattern hair loss, follicles undergo miniaturization, shrinking from terminal to vellus-like hairs. Traditionally, this process is thought to progress gradually over a number of follicular cycles. However, it is unlikely that miniaturization can be explained only by a series of progressively shorter anagen cycles. Simple calculations show that this process would take too long for significant miniaturization to occur secondary to shorter anagen cycles alone, especially in view of the latent lag period seen in pattern hair loss that occurs between the loss of a telogen hair and the appearance of an anagen hair. Evidence is presented to support a new concept that miniaturization is an abrupt, large-step process that also can be reversed in 1 hair cycle, as has been shown clinically, with confirmatory histologic evidence, in patients with pattern hair loss responding to finasteride treatment. It is hypothesized that the miniaturization seen with pattern hair loss may be the direct result of reduction in the cell number and, hence, size of the dermal papilla.


Asunto(s)
Alopecia/fisiopatología , Folículo Piloso/fisiopatología , Humanos
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