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1.
Br J Dermatol ; 174(5): 1096-1097, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26616160

RESUMEN

The effect of sex hormones on pyoderma gangrenosum (PG) has not been reported. We report the case of a 34-year-old woman with chronic PG leg ulcers who was found to have recurring, premenstrual flares of PG. Her PG flares were controlled with the use of ethinyl estradiol/drospirenone.

2.
Br J Dermatol ; 165(4): 751-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21668434

RESUMEN

Human skin is colonized by bacteria. The development of new genomic microbiological techniques has revealed that the bacterial ecology of human skin is far more complex than previously imagined and includes many fastidious or noncultivable bacterial species which are found on both normal and diseased skin. In nature, the predominant bacterial phenotype on epithelial surfaces is that of organisms organized within a biofilm. This contrasts with the widely held belief that bacteria are planktonic, i.e. free-floating single cells. Biofilms are sessile bacterial communities encased in an extracellular matrix that have a well-developed communication system and can regulate bacterial growth and metabolism, confer resistance to antimicrobials and to host inflammatory cells, and alter host metabolism. Biofilms have been observed on healthy skin and in a number of dermatological conditions, including some that were previously thought not to have an infectious aetiology. Here we review the concept of biofilms and their role in cutaneous health and disease.


Asunto(s)
Biopelículas , Enfermedades Cutáneas Bacterianas/microbiología , Piel/microbiología , Acné Vulgar/microbiología , Antibacterianos/uso terapéutico , Dermatitis Atópica/microbiología , Forunculosis/microbiología , Humanos , Impétigo/microbiología , Pruebas de Sensibilidad Microbiana , Miliaria/microbiología , Onicomicosis/microbiología , Piel/lesiones , Enfermedades Cutáneas Bacterianas/tratamiento farmacológico
3.
Clin Microbiol Infect ; 16(12): 1762-9, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21077984

RESUMEN

Chronic wounds cause substantial morbidity and disability. Infection in chronic wounds is clinically defined by routine culture methods that can take several days to obtain a final result, and may not fully describe the community of organisms or biome within these wounds. Molecular diagnostic approaches offer promise for a more rapid and complete assessment. We report the development of a suite of real-time PCR assays for rapid identification of bacteria directly from tissue samples. The panel of assays targets 14 common, clinically relevant, aerobic pathogens and demonstrates a high degree of sensitivity and specificity using a panel of organisms commonly associated with chronic wound infection. Thirty-nine tissue samples from 29 chronic wounds were evaluated and the results compared with those obtained by culture. As revealed by culture and PCR, the most common organisms were methicillin-resistant Staphylococcus aureus (MRSA) followed by Streptococcus agalactiae (Group B streptococcus) and Pseudomonas aeruginosa. The sensitivities of the PCR assays were 100% and 90% when quantitative and qualitative culture results were used as the reference standard, respectively. The assays allowed the identification of bacterial DNA from ten additional organisms that were not revealed by quantitative or qualitative cultures. Under optimal conditions, the turnaround time for PCR results is as short as 4-6 h. Real-time PCR is a rapid and inexpensive approach that can be easily introduced into clinical practice for detection of organisms directly from tissue samples. Characterization of the anaerobic microflora by real-time PCR of chronic wounds is warranted.


Asunto(s)
Bacterias Aerobias/clasificación , Bacterias Aerobias/aislamiento & purificación , Infecciones Bacterianas/diagnóstico , Técnicas de Tipificación Bacteriana , Reacción en Cadena de la Polimerasa/métodos , Heridas y Lesiones/microbiología , Bacterias Aerobias/genética , Infecciones Bacterianas/microbiología , Recuento de Colonia Microbiana , Medios de Cultivo , ADN Bacteriano/análisis , ADN Bacteriano/aislamiento & purificación , Humanos , Sensibilidad y Especificidad , Factores de Tiempo
4.
Acad Med ; 73(10): 1107-13, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9795630

RESUMEN

PURPOSE: To assess the state of managed care knowledge and attitudes and to evaluate the effects of a two-day course on participants' knowledge, attitudes, and behavioral intentions. METHOD: In 1996, the University of California, Davis, Medical School invited all medical students, residents, faculty, and administrators to participate in one of two sessions of a two-day course on managed care. Participants in the first session were given both pre- and post-course questionnaires. Participants in the second session were given only post-course questionnaires. The questionnaires measured objective knowledge, attitudes, and behavioral intentions. Participants (other than administrators) who completed the questionnaires also received a follow-up questionnaire six months after the seminar. RESULTS: The two sessions were attended by 818 UC Davis medical students, residents, faculty, and administrators: after excluding 33 non-physician administrators, 428 completed survey packets (55%) were available for full analysis. Before the course, participants in the first session correctly answered on average only 46% of 32 questions about managed care knowledge. Course attendance was associated with significant gains in knowledge (to 67% correct, p < .001) and a marked increase in appreciation for the cost-control effectiveness of managed care (from 3.35 to 3.98 on a five-point scale, p < .001). Knowledge gains were greatest among medical students; changes in attitudes and behavioral intentions were least among residents. Among respondents to a follow-up survey, the changes were partially sustained six months later. CONCLUSION: Within this academic medical center, baseline levels of managed care knowledge were low among faculty as well as among trainees, and attitudes reflected a blend of negativism and wishful thinking. An intensive two-day educational program effectively increased knowledge and changed selected attitudes among critical academic constituencies. Other academic medical centers may wish to consider presenting similar programs in order to orient their faculties and trainees to the economic realities of the foreseeable future.


Asunto(s)
Actitud del Personal de Salud , Educación Continua , Docentes Médicos , Programas Controlados de Atención en Salud/organización & administración , Estudiantes de Medicina , Centros Médicos Académicos , Adulto , California , Femenino , Humanos , Masculino , Desarrollo de Personal , Encuestas y Cuestionarios
5.
Br J Dermatol ; 136(2): 190-6, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9068730

RESUMEN

We report on dominantly inherited epidermal acantholysis in three dogs, a sire and two female offspring. The skin lesions were characterized by hairless, hypertrophic plaques. Histopathologically, these lesions showed epidermal hyperplasia with individual enlargement of keratinocytes, extensive acantholysis and minimal dyskeratosis. Ultrastructural analysis revealed that attachment plaques of desmosomes were still intact while some tonofilaments were detached from them in early lesions; there were well-developed microvilli at dissociated cell surfaces. The data imply that these animals have undergone a process similar to human benign familial chronic pemphigus (BFCP). Immunohistochemical examination revealed that staining for E-cadherin and actin variably remained in dissociated keratinocytes. Focal intracellular staining for desmosomal glycoproteins and desmosomal proteins were observed within the dissociated keratinocytes. This dominantly inherited acantholytic disease in dogs could be a useful animal model for investigating the pathogenesis of BFCP in humans.


Asunto(s)
Acantólisis/veterinaria , Modelos Animales de Enfermedad , Enfermedades de los Perros/genética , Pénfigo Familiar Benigno/genética , Acantólisis/genética , Acantólisis/patología , Animales , Enfermedades de los Perros/metabolismo , Enfermedades de los Perros/patología , Perros , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Masculino , Microscopía Electrónica , Linaje , Piel/metabolismo , Piel/ultraestructura
6.
J Dermatol ; 23(11): 769-72, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8990699

RESUMEN

Human mast cells contain large quantities of chymotryptic and tryptic proteinases. In human skin, mast cells contain both chymase and tryptase, whereas, in the mucosa of the gastrointestinal tract, mast cells contain primarily tryptase. By contrast, submucosal mast cells in the gastrointestinal tract are of the connective tissue type because they contain both chymase and tryptase. Chymase has a broad array of biological functions which include; activation of angiotensin, cleavage of basement membrane through the lamina lucida, activation of IL1 beta, and potentiation of histamine. Chymase may play a significant role in the control of a variety of biological phenomena. Urticaria pigmentosa is a disease characterized by deposition of "normal" connective tissue mast cells within the skin. The source of these mast cells is the bone marrow and mast cells appear to be deposited within other internal organs in almost all cases. Excretion of histamine and prostaglandin metabolites correlates with the deposition of mast cells in extracutaneous sites. High potency steroids under occlusion for six week results in long-lasting clearing of the cutaneous lesions with minimal side effects.


Asunto(s)
Mastocitosis , Serina Endopeptidasas/metabolismo , Enfermedades de la Piel , Quimasas , Diagnóstico Diferencial , Humanos , Mastocitosis/diagnóstico , Mastocitosis/fisiopatología , Mastocitosis/terapia , Piel/patología , Piel/fisiopatología , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/enzimología , Enfermedades de la Piel/fisiopatología
7.
J Pathol ; 178(3): 290-6, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8778334

RESUMEN

The plasminogen activators, tissue type and urokinase type (tPA and uPA, respectively), have been identified in various malignancies and have been implicated in both local growth and metastatic spread. To characterize plasminogen activator expression more fully in human basal cell carcinoma, the localization of uPA and tPA mRNAs was evaluated by in situ hybridization. Nodular basal cell carcinomas demonstrated uPA expression in most cases, whereas the non-nodular subtypes were negative. Message for uPA was identified within tumour islands (11/12 cases), scattered fibroblast-like stromal cells (6/12 cases), and the basal layer of the overlying epidermis (10/12 cases). In addition, signal for uPA was elevated and pronounced in areas where the epidermis merged into invasive basal cell carcinoma in the superficial papillary dermis in some cases. Message for uPA was often associated with ulceration or erosion of the overlying epithelium. Expression of tPA was noted in the epidermis (3/12 cases) and in tumour cells (4/12 cases), but tended to be focal and sparse. These results suggest that complex interactions involving uPA expression occur between the tumour, the stroma, and the overlying epidermis. Both the stroma and the epidermis may contribute to local spread of the tumour through production of uPA and consequent plasmin-mediated activation of collagenases and metalloproteinases.


Asunto(s)
Carcinoma Basocelular/química , Activadores Plasminogénicos/análisis , Neoplasias Cutáneas/química , Epidermis/química , Epitelio/química , Humanos , Hibridación in Situ , Activador de Tejido Plasminógeno/análisis , Activador de Plasminógeno de Tipo Uroquinasa/análisis
8.
J Am Acad Dermatol ; 34(2 Pt 1): 204-8, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8642083

RESUMEN

BACKGROUND: Chronic venous insufficiency may be associated with lipodermatosclerosis or atrophie blanche. Coagulation abnormalities may be related to these cutaneous disorders. OBJECTIVE: Our purpose was to determine whether fibrinolytic abnormalities exist in patients with lipodermatosclerosis or atrophie blanche. METHODS: A case control study of patients with venous disease and atrophie blanche or lipodermatosclerosis was performed. Plasma levels of tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) in a resting and venous occluded state were measured. RESULTS: Plasma levels of PAI-1 were different between the two groups of patients. The lipodermatosclerosis group had significantly higher levels of PAI-1 in both the resting and venous occluded states (p < 0.001). Patients with atrophie blanche had milder elevations of PAI-1 in the resting and venous occluded state (p = 0.06). CONCLUSION: Fibrinolytic abnormalities are present in patients with venous disease. These abnormalities are different between patients with lipodermatosclerosis and patients with atrophie blanche.


Asunto(s)
Fibrinólisis , Esclerodermia Localizada/fisiopatología , Enfermedades Cutáneas Vasculares/fisiopatología , Piel/patología , Insuficiencia Venosa/fisiopatología , Anciano , Análisis de Varianza , Atrofia , Trastornos de la Coagulación Sanguínea/fisiopatología , Estudios de Casos y Controles , Femenino , Fibrinólisis/fisiología , Humanos , Masculino , Persona de Mediana Edad , Inhibidor 1 de Activador Plasminogénico/sangre , Descanso , Esclerodermia Localizada/sangre , Enfermedades Cutáneas Vasculares/sangre , Telangiectasia/sangre , Telangiectasia/fisiopatología , Tromboflebitis/sangre , Tromboflebitis/fisiopatología , Activador de Tejido Plasminógeno/sangre , Úlcera Varicosa/sangre , Úlcera Varicosa/fisiopatología , Insuficiencia Venosa/sangre
9.
Dev Biol ; 170(2): 289-98, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7649363

RESUMEN

Plasminogen activator enzymes have been implicated in the regulation of growth, migration, and differentiation which occur continually in normal epidermis and cyclically in the hair follicle. To elucidate further the importance of plasminogen activation in epidermal physiology, studies were conducted using mice transgenic for human plasminogen activator inhibitor 1 (PAI-1). The epidermis of the newborn (4-7 days) transgenic mice was flaky and showed delayed hair growth compared to that of their control littermates. Histologic analyses revealed a greatly thickened stratum corneum in the transgenics. By 2 weeks after birth, no differences in epidermal morphology were apparent between transgenic and control littermates. Using in situ hybridization, immunocytochemistry, and in situ reverse zymography techniques, epidermal PAI-1 expression was correlated temporally with the aberrant epidermal morphology. These data implicate plasminogen activator activity in the regulation of epidermal shedding and follicular neogenesis.


Asunto(s)
Inhibidor 1 de Activador Plasminogénico/genética , Anomalías Cutáneas , Piel/metabolismo , Animales , Animales Recién Nacidos , Cabello/anomalías , Cabello/metabolismo , Humanos , Ratones , Ratones Transgénicos , Activadores Plasminogénicos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo
10.
J Cell Physiol ; 163(2): 257-65, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7706370

RESUMEN

Autocrine activation of the epidermal growth factor (EGF) receptor on keratinocytes has been recognized as an important growth regulatory mechanism involved in epithelial homeostasis, and, possibly, hyperproliferative diseases. Insulin-like growth factor (IGF)-1 and insulin have been shown to be paracrine keratinocyte mitogens that bind to the type I IGF receptor which is expressed on actively proliferating keratinocytes in situ. In this report, we demonstrate that IGF-1/insulin induced production of keratinocyte-derived autocrine growth factors that bind to the EGF receptor. Increased steady-state mRNA levels for transforming growth factor alpha (TGF-alpha) and for amphiregulin (AR) were observed upon incubation of keratinocytes with mitogenic concentrations of IGF-1. IGF-1 also induced production and secretion of TGF-alpha and AR proteins as detected by immunoassays. An EGF receptor antagonistic monoclonal antibody abolished the mitogenic effect of IGF-1 on cultured keratinocytes. These results suggest that stimulation of keratinocyte growth of IGF-1 requires activation of an EGF receptor-mediated autocrine loop.


Asunto(s)
Receptores ErbB/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Insulina/farmacología , Péptidos y Proteínas de Señalización Intercelular , Queratinocitos/metabolismo , Anfirregulina , Anticuerpos/inmunología , División Celular/efectos de los fármacos , Familia de Proteínas EGF , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/inmunología , Glicoproteínas/metabolismo , Sustancias de Crecimiento/metabolismo , Humanos , Ligandos , Factor de Crecimiento Transformador alfa/metabolismo
12.
Arch Dermatol ; 130(12): 1539-42, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7986128

RESUMEN

Managed care is the predominant method of health care delivery in Sacramento, Calif; the effect on our academic medical center is profound. The lessons we are learning in the development of a university-based health care network have applicability to dermatology. The future of dermatology demands that all practicing dermatologists have an understanding of the challenges and that they participate in the design of appropriate cost-effective strategies for the future.


Asunto(s)
Dermatología/tendencias , Educación Médica/tendencias , Programas Controlados de Atención en Salud , Centros Médicos Académicos , California
13.
Wound Repair Regen ; 2(3): 165-70, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17156107

RESUMEN

Chronic wounds represent a worldwide problem. For laboratory and clinical research to adequately address this problem, a common language needs to exist. This language should include a system of wound classification, a lexicon of wound descriptors, and a description of the processes that are likely to affect wound healing and would healing end points. The report that follows defines wound, acute wound, chronic wound, healing and forms of healing, wound assessment, wound extent, wound burden, and wound severity. The utility of these definitions is demonstrated as they relate to the healing of a skin wound, but these definitions are broadly applicable to all wounds.

14.
Exp Dermatol ; 3(2): 85-8, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7921656

RESUMEN

Keratinocytes propagated in low calcium (30 microM CaCl2) serum-free media grow in a monolayer and exhibit morphologic and biosynthetic phenotypes most similar to those of keratinocytes in the basal layer of the normal epidermis. When the calcium in the media is elevated to 1 mM, the cells stratify and differentiate. The effects of calcium on human foreskin keratinocyte expression of urokinase type (uPA) and tissue type (tPA) plasminogen activator enzymes and plasminogen activator inhibitor 1 and 2 (PAI-1, PAI-2) were assessed by Northern analyses. Our data show that keratinocytes, cultured in the presence of low and high CaCl2 concentrations, express transcripts for uPA and PAI-2. Message levels for uPA were dramatically reduced in cultures stimulated with calcium, whereas those for PAI-2 were only slightly decreased. Little PAI-1 mRNA and no tPA mRNA were detected, independent of calcium levels. Actin mRNA levels were not modulated consequent to calcium stimulation. Hybridizations to 28S ribosomal RNA confirmed that equal amounts of RNA were analyzed from cells grown under low and high calcium conditions. These data demonstrate that keratinocytes, propagated in serum-free media under low and high calcium conditions, are similar to normal human epidermis with respect to their expression of regulators of plasminogen activation. Additionally, they suggest that the ratio of PAI-2 to uPA increases with keratinocyte differentiation.


Asunto(s)
Calcio/farmacología , Queratinocitos/citología , Inhibidor 2 de Activador Plasminogénico/fisiología , Activador de Plasminógeno de Tipo Uroquinasa/fisiología , Northern Blotting , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Medios de Cultivo Condicionados/farmacología , Humanos , Queratinocitos/química , Queratinocitos/fisiología , Masculino , Inhibidor 2 de Activador Plasminogénico/análisis , Inhibidor 2 de Activador Plasminogénico/genética , ARN Mensajero/análisis , ARN Mensajero/genética , Activador de Plasminógeno de Tipo Uroquinasa/análisis , Activador de Plasminógeno de Tipo Uroquinasa/genética
15.
Arch Dermatol ; 130(4): 489-93, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8166487

RESUMEN

BACKGROUND: Chronic wounds represent a worldwide problem. For laboratory and clinical research to adequately address this problem, a common language needs to exist. OBSERVATION: This language should include a system of wound classification, a lexicon of wound descriptors, and a description of the processes that are likely to affect wound healing and wound healing end points. CONCLUSIONS: The report that follows defines wound, acute wound, chronic wound, healing and forms of healing, wound assessment, wound extent, wound burden, and wound severity. The utility of these definitions is demonstrated as they relate to the healing of a skin wound, but these definitions are broadly applicable to all wounds.


Asunto(s)
Úlcera por Presión/diagnóstico , Piel/lesiones , Cicatrización de Heridas , Heridas y Lesiones/diagnóstico , Enfermedad Aguda , Enfermedad Crónica , Humanos , Guías de Práctica Clínica como Asunto , Índice de Severidad de la Enfermedad , Terminología como Asunto , Heridas y Lesiones/clasificación
16.
J Immunol ; 152(8): 4062-9, 1994 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-8144971

RESUMEN

This study establishes the primary structure of human skin chymase and provides further evidence for the presence of a cathepsin G-like proteinase within human mast cells. The amino acid sequence of human skin chymase was established by protein methods and by analysis of PCR amplification products obtained with cDNA-derived from urticaria pigmentosa (UP) lesions. UP is a disease characterized by skin lesions containing high numbers of mast cells. Proteolytic digests of human chymase purified from normal skin yielded 10 resolvable peptides that were sequenced by automated Edman degradation. The amino acid sequences for these peptides combined with the sequence obtained for the protein's NH2-terminal region (35 residues) accounted for 137 residues of the human skin chymase sequence. This partial amino acid sequence corresponded to the sequence of human heart chymase, a proteinase isolated from heart tissue with immunologic and hydrolytic properties similar to skin chymase. PCR amplification of UP-derived cDNA with primers based on the cDNA structure of heart chymase demonstrated a single amplification product of expected size which was subcloned and sequenced. The amino acid sequence (135 residues) deduced from this product was identical to that of heart chymase in the region between the primers. This sequence, along with that established for the purified protein, constituted 99% of the heart chymase primary structure, strongly indicating that human skin and heart chymases have identical primary structures. Amplification of the same UP-cDNA with primers coding for the NH2- and COOH-terminal sequences of human neutrophil cathepsin G also produced a specific amplification product which was sequenced. The deduced amino acid sequence between the primers was identical to that reported for neutrophil cathepsin G, indicating that the protein of cutaneous mast cells previously shown to be immunologically cross-reactive with neutrophil cathepsin G has a comparable amino acid sequence. UP-cDNA demonstrating amplification products for cathepsin G did not demonstrate amplification products for human neutrophil elastase, suggesting that the cathepsin G PCR amplification product was not derived from neutrophils or monocytes possibly contaminating the lesion. These studies provide further evidence that human skin mast cells contain two different chymotrypsin-like proteinases.


Asunto(s)
Catepsinas/química , Mastocitos/enzimología , Serina Endopeptidasas/química , Urticaria Pigmentosa/enzimología , Secuencia de Aminoácidos , Secuencia de Bases , Catepsina G , Catepsinas/metabolismo , Quimasas , Clonación Molecular , Cartilla de ADN/química , Expresión Génica , Humanos , Datos de Secuencia Molecular , Miocardio/enzimología , ARN Mensajero/genética , Serina Endopeptidasas/metabolismo , Piel/enzimología
17.
J Invest Dermatol ; 102(3): 333-8, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8120416

RESUMEN

The plasminogen activators, tissue type and urokinase type (tPA and uPA, respectively) have been identified in human skin under normal conditions and in various inflammatory dermatoses, including psoriasis. By Northern blot analyses, mRNA for uPA, but not for tPA, has been previously identified in epidermal extracts from normal skin, whereas in psoriasis, mRNA for tPA is readily detected. To further characterize uPA and tPA expression in psoriasis, the localization of uPA and tPA mRNAs was evaluated by in situ hybridization. Studies were conducted using lesional and nonlesional skin of patients with psoriasis as well as normal skin. Additionally, in situ zymography using casein gel overlays was utilized to assess enzymatic activity. In psoriatic lesional skin, both uPA and tPA mRNAs were demonstrated by in situ hybridization. Message for tPA was observed throughout the epidermis with areas of accentuation in the superficial stratum spinosum. Message for uPA was more focal and was localized primarily in the basal layer. Zymography showed tPA activity was coordinately increased in psoriatic lesions. Uninvolved skin of psoriatic patients was similar to that of normal skin with respect to expression of plasminogen activators. In normal epidermis, neither tPA nor uPA mRNA could be detected by in situ hybridization. Activity for uPA, but not tPA, was observed by zymography. These studies suggest that alterations in plasminogen activators expression may contribute to the pathogenesis of psoriasis.


Asunto(s)
Psoriasis/enzimología , Piel/enzimología , Activador de Tejido Plasminógeno/fisiología , Activador de Plasminógeno de Tipo Uroquinasa/fisiología , Humanos , Inmunohistoquímica , Hibridación in Situ
18.
J Clin Invest ; 92(5): 2401-7, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8227357

RESUMEN

Pemphigus vulgaris is an autoimmune blistering disease that is induced by binding of antibodies to a 130/85-kD protein complex on epidermal keratinocytes. An in vivo experimental model of this disease was developed by reconstituting severe combined immunodeficiency (SCID) mice with 1-10 x 10(7) PBL from patients with naturally occurring pemphigus vulgaris. Of 49 reconstituted mice, 34 (69%) produced human IgG levels of > 0.1 mg/ml. Circulating anti-pemphigus antibodies were found in 20 of the 34 successfully reconstituted mice; 44% of these animals had deposits of human IgG in their own skin after it was traumatized by either heat or cold. Spontaneous pemphigus vulgaris-like blisters associated with human IgG deposits were rarely found in mouse skin. By contrast, allogeneic human skin grafted to 10 to 12 mice before reconstitution with patients' PBL developed pemphigus vulgaris-like lesions containing human IgG deposits. These results demonstrate that SCID mice can serve as a model of an antibody-mediated human autoimmune skin disease.


Asunto(s)
Transfusión de Linfocitos , Ratones SCID/inmunología , Pénfigo/inmunología , Trasplante de Piel/inmunología , Adulto , Animales , Autoanticuerpos/sangre , Vesícula/inmunología , Vesícula/patología , Humanos , Inmunoglobulinas/biosíntesis , Recién Nacido , Ratones , Pénfigo/patología , Especificidad de la Especie
19.
J Cell Physiol ; 156(3): 487-96, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8360256

RESUMEN

The involvement of protein kinase C (PKC) in epidermal growth factor (EGF)-induced human keratinocyte migration was studied with the phagokinetic assay. It was concluded that PKC activation does not mediate, but rather inhibits, EGF-induced keratinocyte migration. The following experimental observations support these conclusions: 1) The PKC inhibitor H-7 did not inhibit EGF-induced migration but instead led to a modest enhancement. 2) PKC activators such as phorbol-12-myristate-13-acetate (PMA), phorbol-12,13-dibutyrate (PDBu), and 1,2-dioctanoly-sn-glycerol inhibited migration, but biologically inactive 4 alpha-PMA had no effect. 3) PMA did not inhibit keratinocyte attachment and spreading but blocked migration almost immediately after addition. 4) Migration of PKC-depleted cells, which were produced by prolonged treatment with PDBu, was enhanced similarly to normal cells by EGF. 5) PKC-depleted cells were not susceptible to the inhibitory effects of phorbol esters on migration. Additional experiments, in which cells were preactivated with EGF, suggested that PKC inhibits the EGF effect at a post-receptor level. The inhibitory effect of PKC on keratinocyte migration was not restricted to EGF-induced migration; PKC activation also inhibited keratinocyte migration induced by bovine pituitary extract, insulin, insulin-like growth factor-1, and keratinocyte growth factor.


Asunto(s)
Queratinocitos/fisiología , Proteína Quinasa C/metabolismo , Tirfostinos , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina , Catecoles/farmacología , Movimiento Celular/efectos de los fármacos , Sinergismo Farmacológico , Activación Enzimática , Factor de Crecimiento Epidérmico/farmacología , Receptores ErbB/efectos de los fármacos , Sustancias de Crecimiento/farmacología , Humanos , Isoquinolinas/farmacología , Nitrilos/farmacología , Ésteres del Forbol/farmacología , Piperazinas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores
20.
Br J Dermatol ; 129(3): 270-4, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8286223

RESUMEN

Patients with venous leg ulcers have a readily recognized clinical syndrome of shallow ulcers, oedema, leg pain, venous ankle blush, lipodermatosclerosis, varicose veins, hyperpigmentation, and atrophie blanche, and they are assumed to have venous abnormalities. We examined 43 patients with venous leg ulcers, and compared those with obvious venous abnormalities (defined as historical or clinical evidence of deep venous thrombosis or varicose veins) with those with presumed venous abnormalities (defined as lacking any such evidence), to see if they presented with different clinical features. We found that both groups had similar clinical features, with the exception that lipodermatosclerosis was present more frequently in those patients with obvious venous abnormalities (94 vs. 36%, P < 0.001). Most patients with presumed venous abnormalities had musculoskeletal conditions which might cause calf pump dysfunction (91%). Using air plethysmography, we were unable to confirm that all patients with presumed venous abnormalities did have intrinsic venous abnormalities. We propose that ulcers occurring in this clinical syndrome be designated as calf pump dysfunction ulcers (CPD ulcers), rather than venous ulcers.


Asunto(s)
Úlcera Varicosa/etiología , Arteriosclerosis/complicaciones , Arteriosclerosis/patología , Atrofia , Edema , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dolor/etiología , Úlcera Varicosa/patología , Venas/patología
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