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1.
Eur Endod J ; 6(1): 90-97, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33762534

RESUMO

OBJECTIVE: To define surface, mechanical, microstructural and metallurgical features of conventional One-Shape (OShape) and heat-treated OneCurve (OCurve) nickel-titanium instruments. METHODS: Instruments were analysed by scanning electron microscopy (SEM) on new instruments and after simulated clinical use (SCU). Cyclic fatigue testing was performed and the number of cycles to fracture (NCF) and the length of the fractured instruments were measured (Mann-Whitney test). Fractured instruments during cyclic fatigue testing were then inspected by SEM fractographic analysis. Field emission gun scanning scanning electron microscopy (FEG-SEM), energy-dispersive X-ray spectroscopy (EDX) and micro-Raman spectroscopy were used to assess alloy surface chemistry. Focused ion beam (FIB) was performed to analyse the oxide layer on the surface of OCurve before and after SCU. X-Ray diffraction (XRD), metallographic evaluation and differential scanning calorimetry (DSC) were used to determine martensitic/austenitic phase transformation temperatures. RESULTS: SEM observations on new instruments revealed a smooth regular surface with flattened milling grooves. No wear features were detected after SCU. OCurve exhibited a higher cyclic fatigue resistance (P<0.05), slower crack propagation and a surface layer of TiO2. Metallographic analysis and XRD showed the prevalence of martensitic grains on OCurve instruments that were stable at body temperature as confirmed by DSC analysis. Furthermore, DSC demonstrated a shift in the temperature transformation ranges suggesting an increase of martensite phase in autoclaved OCurve instruments. CONCLUSION: Heat treatment processes were confirmed as a valid enhancement of the properties of the new generation NiTi instruments. OCurve presented a significant improvement over OShape regarding both mechanical and metallurgical characteristics.


Assuntos
Temperatura Alta , Preparo de Canal Radicular , Teste de Materiais , Metalurgia , Microscopia Eletrônica de Varredura
2.
Materials (Basel) ; 13(17)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32847048

RESUMO

To evaluate the properties of two nickel-titanium (NiTi) reciprocating endodontic instruments (commercially known as Procodile and Reziflow), a total of 40 size 25 and 0.06 taper new Procodile and Reziflow instruments (n = 20) were subjected to cyclic fatigue tests (60° angle of curvature, 5-mm radius) at 20 °C and 37 °C and a torsional test based on ISO 3630-1. The fracture surface of each fragment was examined. The morphological, mechanical, chemical, thermal, and phase composition characteristics of the files were investigated by field-emission gun scanning electron microscopy (FEG-SEM) equipped with an energy-dispersive X-ray (EDX) detector, focused ion beam analysis (FIB), micro-Raman spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Auger electron spectroscopy (AES). Reziflow showed higher cyclic fatigue resistance than Procodile at 37 °C (p < 0.05). The maximum torsional strength of Procodile was lower than that of Reziflow (p < 0.05). No difference was found between their angular rotations to fracture (p > 0.05). SEM, FIB, Micro-Raman, and AES analyses revealed the presence of an Nb/Nb2O5 coating on the Procodile surface. DSC and XRD analysis confirmed that both files consist of an almost austenitic phase structure at 37 °C. The cyclic fatigue resistance of Procodile and Reziflow significantly decreases upon exposure to body temperature.

4.
J Am Acad Dermatol ; 67(4): 617-22, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22243765

RESUMO

BACKGROUND: Rituximab induces depletion of B cells and has shown efficacy in antibody-mediated autoimmune disorders. In studies on small series of patients with pemphigus, rituximab administration results in significant improvement. However, differences in inclusion criteria, treatment protocols, and follow-up make it difficult to derive uniform conclusions. OBJECTIVES: We sought to test the efficacy and tolerability of rituximab as adjuvant therapy to corticosteroids in the treatment of pemphigus. METHODS: In all, 42 patients with pemphigus were treated with rituximab and followed up for up to 5 years. No additional immunosuppressive agents were used. Steroids were rapidly tapered. Outcomes were the proportion of patients who achieved a complete response on or off therapy, the rate of discontinuation of corticosteroid within 6 months, length of remission, time to relapses, and occurrence of adverse events. RESULTS: In all, 36 of 42 patients (86%; 95% confidence interval 75%-96%) achieved a complete response on or off therapy and discontinued steroids within 6 months from induction therapy. Six patients had a complete response off therapy with an additional infusion of rituximab 6 months after initial treatment. Twenty patients experienced a total of 34 relapses; the time to relapse was 8 to 64 months. Every relapse was treated with rituximab (500 mg) without corticosteroids, which induced a new complete response. No serious adverse events were observed. LIMITATIONS: Lack of a control group is a limitation. CONCLUSIONS: Rituximab therapy induces prolonged clinical remission in patients with pemphigus. Coadministration of other immunosuppressive agents is not necessary. Relapses can be managed with additional infusions administered on demand.


Assuntos
Anticorpos Monoclonais Murinos/administração & dosagem , Glucocorticoides/administração & dosagem , Fatores Imunológicos/administração & dosagem , Pênfigo/tratamento farmacológico , Prednisona/administração & dosagem , Adulto , Idoso , Anticorpos Monoclonais Murinos/efeitos adversos , Quimioterapia Combinada/métodos , Feminino , Seguimentos , Humanos , Fatores Imunológicos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Pênfigo/imunologia , Recidiva , Indução de Remissão , Rituximab , Resultado do Tratamento
7.
Arch Dermatol ; 143(8): 1033-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17709662

RESUMO

BACKGROUND: Treatment of pemphigus vulgaris can be challenging. Systemic steroids associated with other immunosuppressant agents are the mainstay of therapy and have dramatically reduced morbidity and mortality from pemphigus vulgaris. In some patients, however, these agents are not able to control the disease or have severe adverse effects. Rituximab (MabThera; Roche, Basel, Switzerland), a chimeric monoclonal anti-CD20 antibody, induces depletion of B cells in vivo and has shown efficacy in patients with refractory antibody-mediated autoimmune disorders. We report 10 cases of pemphigus vulgaris and 2 cases of pemphigus foliaceous treated with rituximab--to our knowledge the largest series of patients so far--and review the existing literature on the topic. OBSERVATION: The 12 patients were selected for treatment with the anti-CD20 antibody. Rituximab was administered intravenously at a dosage of 375 mg/m(2) once weekly for 4 weeks. The treatment was well tolerated, and all 12 patients showed a good clinical response during an 18-month follow-up period, along with a consensual decline of the serum antidesmoglein titers. No infectious complications were observed. CONCLUSIONS: Rituximab is able to induce a prolonged clinical remission in patients with both pemphigus vulgaris and pemphigus foliaceous after a single course of 4 treatments. The preliminary experiences worldwide make rituximab a promising therapeutic option for patients with autoimmune diseases. The high costs and the limited knowledge of long-term adverse effects, however, limit its use to selected patients with treatment-resistant or life-threatening disease.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Fatores Imunológicos/uso terapêutico , Pênfigo/tratamento farmacológico , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Estudos de Coortes , Esquema de Medicação , Feminino , Humanos , Fatores Imunológicos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Pênfigo/patologia , Rituximab , Índice de Gravidade de Doença
8.
J Dermatolog Treat ; 17(4): 244-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16971322

RESUMO

Pemphigus foliaceus induced by ionizing radiation therapy is a rare condition. We describe the case of a 70-year-old female who developed pemphigus foliaceus after X-ray treatment for an adenocarcinoma of the left breast. The eruption started at the portal of irradiation and only subsequently spread to other cutaneous areas. Mucosal membranes were not affected. Skin lesions were completely responsive to dapsone therapy.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Dapsona/uso terapêutico , Pênfigo/tratamento farmacológico , Pênfigo/etiologia , Radioterapia/efeitos adversos , Adenocarcinoma/radioterapia , Idoso , Neoplasias da Mama/radioterapia , Feminino , Humanos
9.
Melanoma Res ; 14(5): 367-73, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15457092

RESUMO

Although the long experience acquired with the widespread use of dermoscopy has allowed the establishment of criteria for the recognition of benign and malignant skin lesions, very few data are available on cutaneous melanoma metastases. As the characteristic clinical aspects are multiform and even histological evaluation may sometimes be difficult, we have studied and characterized the patterns of cutaneous melanoma metastases in dermoscopy. In this paper, we report dermoscopic data on 130 histologically confirmed metastases observed in 32 patients affected by melanoma, with particular emphasis on dermoscopic features. Nine dermoscopic elements (homogeneous, saccular, amelanotic, polymorphic and vascular patterns, colour, perilesional erythema, pigmentary halo, peripheral grey spots) were studied in 130 cutaneous melanoma metastases and compared with those of 350 melanomas, 150 common naevi, 40 blue naevi, 40 haemangiomas and 50 basal cell carcinomas. The saccular and vascular patterns (especially polymorphic atypical vessels and winding vessels), as well as pigmentary halo and peripheral grey spots, seem to be the most significant elements suggestive of cutaneous melanoma metastases. The interest in and importance of the dermoscopic aspects of cutaneous melanoma metastases cannot be neglected if the American Joint Committee has determined that microsatellitosis and micrometastases are fundamental in the new TNM staging classification for cutaneous melanoma.


Assuntos
Dermoscopia/métodos , Melanoma/diagnóstico , Melanoma/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Nevo/patologia , Pele/patologia , Dermatopatias/diagnóstico , Dermatopatias/patologia
11.
Clin Cancer Res ; 10(6): 1881-6, 2004 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-15041702

RESUMO

BACKGROUND: Differential diagnosis of melanoma from melanocytic nevi is often not straightforward. Thus, a growing interest has developed in the last decade in the automated analysis of digitized images obtained by epiluminescence microscopy techniques to assist clinicians in differentiating early melanoma from benign skin lesions. PURPOSE: The aim of this study was to evaluate diagnostic accuracy provided by different statistical classifiers on a large set of pigmented skin lesions grabbed by four digital analyzers located in two different dermatological units. EXPERIMENTAL DESIGN: Images of 391 melanomas and 449 melanocytic nevi were included in the study. A linear classifier was built by using the method of receiver operating characteristic curves to identify a threshold value for a fixed sensitivity of 95%. A K-nearest-neighbor classifier, a nonparametric method of pattern recognition, was constructed using all available image features and trained for a sensitivity of 98% on a large exemplar set of lesions. RESULTS: On independent test sets of lesions, the linear classifier and the K-nearest-neighbor classifier produced a mean sensitivity of 95% and 98% and a mean specificity of 78% and of 79%, respectively. CONCLUSIONS: In conclusion, our study suggests that computer-aided differentiation of melanoma from benign pigmented lesions obtained with DB-Mips is feasible and, above all, reliable. In fact, the same instrumentations used in different units provided similar diagnostic accuracy. Whether this would improve early diagnosis of melanoma and/or reducing unnecessary surgery needs to be demonstrated by a randomized clinical trial.


Assuntos
Melanoma/diagnóstico , Diagnóstico por Computador , Diagnóstico Diferencial , Análise Discriminante , Estudos de Viabilidade , Humanos , Melanoma/classificação , Nevo Pigmentado/diagnóstico , Reprodutibilidade dos Testes , Neoplasias Cutâneas/diagnóstico
12.
J Am Acad Dermatol ; 49(6): 1029-36, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14639381

RESUMO

BACKGROUND: Lichenoid dermatoses are composed of a wide spectrum of disorders with a common histopathologic interface pattern but diverse causes and pathophysiology. OBJECTIVE: We describe a series of young patients with a peculiar annular lichenoid dermatitis, the clinical appearance of which initially suggested diagnoses of morphea, mycosis fungoides, or annular erythema. RESULTS: The study involved 23 patients (median age 10 years; age range 5-22 years). Lesions consisted of persistent asymptomatic erythematous macules and round annular patches with a red-brownish border and central hypopigmentation, mostly distributed on the groin and flanks. Histology revealed a peculiar lichenoid dermatitis with massive necrosis/apoptosis of the keratinocytes limited to the tips of rete ridges, in the absence of dermal sclerosis and epidermotropism of atypical lymphocytes. The infiltrate was composed mainly of memory CD4(+) CD30(-) T cells with few B cells and macrophages. Analysis of T-cell receptor-gamma-chain gene rearrangement in skin biopsy specimens revealed polyclonality in all the 15 cases studied. Topical and systemic corticosteroids or phototherapy were effective in most patients with relapse after treatment withdrawal. CONCLUSIONS: We suggest that this is a distinctive inflammatory condition, and we propose to term it "annular lichenoid dermatitis of youth."


Assuntos
Dermatite/patologia , Erupções Liquenoides/patologia , Adolescente , Adulto , Criança , Pré-Escolar , Dermatite/tratamento farmacológico , Dermatite/genética , Feminino , Rearranjo Gênico , Genes Codificadores dos Receptores de Linfócitos T/genética , Humanos , Imuno-Histoquímica , Erupções Liquenoides/tratamento farmacológico , Erupções Liquenoides/genética , Masculino , Prednisona/uso terapêutico
13.
Curr Drug Targets Inflamm Allergy ; 2(1): 81-94, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14561178

RESUMO

Cell migration is mediated by a group of chemotactic cytokines called chemokines: low molecular weight molecules that have been shown as important leukocyte chemical attractants to sites of inflammation and infection. Eotaxin-1, also called CCL11, was first described in 1994, as a highly specific eosinophils chemokine. Many cell types including lymphocytes, macrophages, bronchial smooth muscle cells, endothelial cells and eosinophils, are able to produce this chemokine, predominantly after cytokine stimulation, however little is known about its expression in human skin in vivo. Eotaxin-1 also regulates the chemiotaxis and, in some conditions, activation of basophils, mast cells and T lymphocytes. Chemokine receptors are named from their ligand families, thus the CC chemokine eotaxin-1 binds to the CCR3 receptor which is expressed on eosinophis, mast cells, Th2 type lymphocytes and even on keratinocytes. It seems that eotaxin-1 is one of the most important cytokines involved in tissue inflammation playing a central role in the pathogenesis of allergic airway diseases (asthma and rhinitis), in inflammatory bowel disease and gastrointestinal allergic hypersensitivity and recently it has been proposed as a therapeutical target for these conditions. Our group has studied the role of eotaxin-1 in the pathogenesis of two skin conditions: dermatitis herpetiformis and AIDS-associated eosinophilic folliculitis, demonstrating that this chemokine, together with Th2 type cytokines (IL-13 and IL-4) is important in cell recruitment, inflammation and tissue damage; moreover eotaxin has proven to paly an important role in other skin conditions such as, bullous pemphigoid, pemphigoid gestationis, atopic dermatitis and allergic drug reactions Recent advances in the understanding of eotaxin-1-mediated mechanisms of chemotaxis in allergic and inflammatory conditions may predict that therapeutic antagonism is achievable. This paper will focus on the role that eotaxin and its receptor play in the pathogenetical mechanism in a number of dermatologic diseases, some of which, like atopic dermatitis, may benefit from the introduction of novel and more selective therapeutic options.


Assuntos
Quimiocinas CC/fisiologia , Dermatite/imunologia , Receptores de Quimiocinas/fisiologia , Animais , Quimiocina CCL11 , Quimiocina CCL24 , Quimiocina CCL26 , Dermatite/metabolismo , Dermatite Alérgica de Contato/imunologia , Dermatite Alérgica de Contato/metabolismo , Humanos , Receptores CCR3 , Receptores de Quimiocinas/antagonistas & inibidores
14.
Eur J Dermatol ; 13(2): 177-82, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12695135

RESUMO

Measuring patient satisfaction is regarded as one of the principal methods for obtaining patients' evaluation of services they receive. During the last decades more interest has been devoted to inpatients' preferences and needs. Surveys on patient satisfaction may provide information to hospitals about areas where improvement is needed. In this survey, 648 questionnaires were completed by dermatological inpatients and were analyzed for overall satisfaction and seven satisfaction determinants. Background factors and clinical parameters were considered. Emotional support was recognized as a critical area. "Coordination of care" and "information and education" were identified as the most relevant determinants for overall patient satisfaction. The Hospital Management, taking into account the results, planned training in order to improve personnel's communication skills. This study confirms that patient satisfaction analysis is a useful instrument also among dermatological inpatients, and satisfaction is a valid measure of quality of health care.


Assuntos
Dermatologia/normas , Assistência ao Paciente/normas , Satisfação do Paciente , Adolescente , Adulto , Idoso , Humanos , Pacientes Internados/psicologia , Itália , Masculino , Pessoa de Meia-Idade , Qualidade da Assistência à Saúde/normas , Inquéritos e Questionários
15.
Eur J Dermatol ; 12(6): 600-2, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12459540

RESUMO

Eosinophilic folliculitis (EF) is a rare follicular pruritic papular eruption observed in association with human immunodeficiency virus (HIV). The diagnosis of eosinophilic folliculitis is based on the histologic findings consisting of a sterile inflammatory infiltrate rich in eosinophils involving hair follicles. EF in HIV patients is believed to be an immunoinflammatory response directed either at follicular or skin flora antigens in the late-stage of HIV infection. In this stage, immune response is characterized by a shift from a Th1- to a Th2-dominant cytokine profile and an increased secretion of interleukin-4 and interleukin-5, both known to promote eosinophilia. We describe a case of HIV-associated eosinophilic folliculitis in a 30-year-old black woman referred to us for a pruritic follicular eruption without any other clinical symptom related to the acquired immunodeficiency syndrome. HIV infection presenting with EF has been rarely reported and its occurrence in women is also very rare.


Assuntos
Eosinofilia/patologia , Foliculite/patologia , Infecções por HIV/diagnóstico , Adulto , Biópsia por Agulha , Diagnóstico Diferencial , Eosinofilia/diagnóstico , Feminino , Foliculite/diagnóstico , Soropositividade para HIV , Humanos , Imuno-Histoquímica , Prurido/diagnóstico , Medição de Risco , Dermatopatias Vesiculobolhosas/diagnóstico
16.
Acta Derm Venereol ; 82(3): 200-3, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12353712

RESUMO

Fibroblastic rheumatism is a rare syndrome characterized by the association of multiple cutaneous nodules with symmetric polyarthritis. We report on a patient who presented a 4-year history of pink to skin-coloured nodular lesions symmetrically localized at para-articular sites without evident rheumatological symptoms. Histopathology of a skin nodule led to the diagnosis of fibroblastic rheumatism showing a poorly circumscribed dermal proliferation of spindle and stellate fibroblast-like cells embedded in thickened collagen bundles with a marked reduction of elastic fibres. X-rays of both hands and feet showed metacarpophalangeal, metatarsalphalangeal and interphalangeal erosions, unexpected by patient history. This case of fibroblastic rheumatism appears unique in view of the absence of any clinical manifestation of polyarthritis at 7 years from appearance of skin lesions.


Assuntos
Artrite/patologia , Fibroblastos/patologia , Doenças Reumáticas/patologia , Dermatopatias/patologia , Adulto , Diagnóstico Diferencial , Tecido Elástico/patologia , Fibroblastos/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica , Pele/ultraestrutura , Síndrome
17.
J Invest Dermatol ; 119(3): 670-7, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12230511

RESUMO

To explore the expression and gain more information on the function of transglutaminase 5 enzyme in normal and defective human epidermis, we generated a rat antihuman transglutaminase 5 antiserum elicited against a purified active recombinant protein expressed in the baculovirus system. By use of Western blotting and immunofluorescence methods, the immunospecificity of the antibodies for transglutaminase 5 was tested; no crossreactivity with other transglutaminases (types 1, 2, and 3) was observed, thus allowing histochemistry studies. By indirect immunofluorescence analysis the antibodies decorated the upper layers of normal human epidermis, with consistent staining in the spinous and granular layers. We evaluated transglutaminase 5 expression in comparison with proliferating (keratin 14) and differentiating (transglutaminase 3) markers in different diseases, such as psoriasis, ichthyosis vulgaris, lamellar ichthyosis, and Darier's disease. We observed that transglutaminase 5 contributes, as a secondary effect, to the hyperkeratotic phenotype in ichthyosis (both vulgaris and lamellar) and in psoriasis. In Darier's disease, transglutaminase 5 expression, as well as transglutaminase 3, is completely missregulated, being overexpressed or totally absent in different areas of the same lesion.


Assuntos
Epiderme/enzimologia , Epiderme/patologia , Hiperceratose Epidermolítica/metabolismo , Transglutaminases/análise , Transglutaminases/genética , Especificidade de Anticorpos , Reações Cruzadas , Técnica Indireta de Fluorescência para Anticorpo , Regulação Enzimológica da Expressão Gênica , Humanos , Hiperceratose Epidermolítica/patologia , Ictiose Vulgar/metabolismo , Ictiose Vulgar/patologia , Queratinócitos/enzimologia , Queratinócitos/patologia , Fenótipo , Psoríase/metabolismo , Psoríase/patologia , Transfecção , Transglutaminases/imunologia
19.
Free Radic Res ; 36(4): 471-7, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12069113

RESUMO

Skin surface lipids (SSL), a very complex mixture of sebum mixed to small amounts of epidermal lipids, mantle the human epidermis, thus representing the outermost protection of the body against exogenous oxidative insults. The present work is a systematic and quantitative analysis of upper-chest SSL and their content in antioxidants in 100 healthy volunteers, divided into five age groups using TLC, HPLC, and GC-MS methods. Further, the effect of exposing SSL in vitro to increasing doses of UV irradiation was examined. Straight monounsaturated and diunsaturated as well as branched monounsaturated fatty acids of triglycerides and pooled fractions were found to be higher at maturity than in childhood and in advancing age. Diunsaturated fatty acids were below 3% of the total and constituted exclusively of C18:2delta5,8, C20:2delta7,10, C18:2delta9,12. Squalene, vitamin E (vit. E) and Coenzyme Q10 (CoQ10) were found to increase from childhood to maturity to decrease again significantly in old age. Vitamin E and CoQ10 were the only known lipophilic antioxidants present in SSL. In spite of their low levels they were found to synergically inhibit the UV induced depletion of squalene, cholesterol and of unsaturated fatty acids of SSL. In fact, exposure of SSL to increasing amounts of UV irradiation led preferentially to lowering of the levels of vit. E and CoQ10. Four minimal erythema dose (MED) (5.6J/cm2) were able to deplete 84% vit. E and 70% ubiquinone, and only 13% squalene. Diunsaturated and monounsaturated fatty acids as well as cholesterol were unaffected even following 10 MED UV exposures, which produced a 26% loss of squalene. The same UV dose when applied in the absence of vit. E and CoQ10 produced a 90% decrease of squalene.


Assuntos
Antioxidantes/metabolismo , Metabolismo dos Lipídeos , Sebo/metabolismo , Envelhecimento da Pele/fisiologia , Pele/metabolismo , Ubiquinona/análogos & derivados , Administração Tópica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Disponibilidade Biológica , Criança , Colesterol/metabolismo , Coenzimas , Citoproteção , Ácidos Graxos/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/efeitos da radiação , Esqualeno/metabolismo , Triglicerídeos/metabolismo , Ubiquinona/metabolismo , Raios Ultravioleta , Vitamina A/metabolismo , Vitamina E/metabolismo
20.
Arch Dermatol Res ; 293(11): 552-9, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11876523

RESUMO

Chemokines are important mediators of immune-mediated skin diseases. Allergic contact dermatitis (ACD) is the most thoroughly investigated T cell-mediated disorder because of the ability to easily reproduce the lesions in humans and the availability of an excellent mouse model. Migration of dendritic cells from the skin to lymph nodes is absolutely required for induction of hapten sensitization, and depends upon expression of CCR7 by mature dendritic cells and SLC in the lymph nodes. During expression of ACD, recruitment of T lymphocytes is driven by chemokines exposed on the surface of endothelial cells or released by activated resident skin cells such as mast cells, fibroblasts and keratinocytes. Chemokines are produced in a coordinated and sequential manner, with IL-8 and RANTES induced by TNF-alpha during early stages, and MCP-1, IP-10, Mig, I-TAC, I-309 and MDC induced by IFN-gamma during later stages. Infiltrating monocytes, dendritic cells and T cells are additional sources of chemokines for further leukocyte accumulation. Distinct T cell subsets express different chemokine receptors, with type 2 cells mostly attracted by eotaxin, MDC, TARC and I-309, and type 1 cells sensitive to IP-10, Mig, I-TAC, RANTES and MIP-1beta. MCP-1 is effective on both subsets. T regulatory cells, which inhibit dendritic cell function and are probably involved in the termination of ACD, are sensitive to MCP-1, MIPs and TARC, but express high levels of CCR8 and are more specifically attracted by I-309. Targeting chemokines and chemokine receptors may offer new opportunities for therapeutic interventions in ACD and other chronic inflammatory skin diseases.


Assuntos
Quimiocinas/metabolismo , Dermatite de Contato/metabolismo , Animais , Humanos , Subpopulações de Linfócitos/metabolismo , Receptores de Quimiocinas/metabolismo , Pele/metabolismo
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