Methotrexate for refractory adult atopic dermatitis leads to alterations in cutaneous IL-31 and IL-31RA expression

Abstract Background: Methotrexate (MTX) is an alternative treatment for patients with moderate/severe atopic dermatitis (AD). Objective: The authors evaluated the effect of MTX on the cutaneous expression of cytokines and chemokines that are involved in the inflammatory response in adult AD patients who received treatment with methotrexate for 24 weeks. Methods: The authors conducted a prospective single-institution cohort study with 12 adults with moderate/severe AD who received oral MTX (15 mg/wk for 24 wks) and 10 non-atopic matched controls. The comparison was made of skin biopsies of lesional and non-lesional skin, pre- and post MTX treatment. The authors analyzed mean epidermal thickness and expression of IL-31, IL-31RA, OSMR, TSLP, Ki67, IL-4 mRNA, IL-6, IL-10, TNF-α, IFN-γ, TARC, and CCL-22. Results: There was a reduction in mean epidermal thickness (p = 0.021), an increase in IL-31RA expression (immunohistochemistry) in the epidermis (p = 0.016) and a decrease in IL-31 gene expression (p = 0.019) on lesional AD skin post-MTX treatment. No significant changes in the cutaneous expression of the other evaluated markers were identified. Study limitations: Small sample size and limited length of follow-up. Conclusions: Treatment with MTX in adults with moderate/severe AD reduced epidermal hyperplasia and changed the cutaneous expression of inflammatory cytokines and receptors that are mainly related to pruritus, including IL-31 and IL-31RA.

Leprosy: clinical and immunopathological characteristics

Abstract Leprosy, a disease caused by Mycobacterium leprae, has polymorphic neurocutaneous manifestations strongly correlated with the host immune response. Peripheral neural damage can lead to sensory and motor losses, as well as deformities of the hands and feet. Both innate and acquired immune responses are involved, but the disease has been classically described along a Th1/Th2 spectrum, where the Th1 pole corresponds to the more limited presentations and the Th2 to the multibacillary ones. The aim of this review is to discuss this dichotomy in light of the current knowledge of the cytokines, T helper subpopulations, and regulatory T cells involved in each presentation of leprosy. The text will also address leprosy reactions related to increased inflammatory activity in both limited and multibacillary presentations, leading to exacerbation of chronic signs and symptoms and/or the development of new ones. Despite the efforts of many research groups around the world, there is no standardized serological test/biological marker for diagnosis so far, even in endemic areas, which could contribute to the eradication of leprosy.

Update on vasculitis: overview and relevant dermatological aspects for the clinical and histopathological diagnosis - Part II

Abstract Vasculitis is a group of several clinical conditions in which the main histopathological finding is fibrinoid necrosis in the walls of blood vessels. This article assesses the main dermatological aspects relevant to the clinical and laboratory diagnosis of small- and medium-vessel cutaneous and systemic vasculitis syndromes. The most important aspects of treatment are also discussed.

Update on vasculitis: an overview and dermatological clues for clinical and histopathological diagnosis - part I

Abstract The term vasculitis refers to the inflammation of vessel walls. It may range in severity from a self-limited disorder in one single organ to a life-threatening disease due to multiple organ failure. It has many causes, although they result in only a few histological patterns of vascular inflammation. Vessels of any type and in any organ can be affected, a fact that results in a broad variety of signs and symptoms. Different vasculitides with indistinguishable clinical presentations have quite different prognosis and treatments. This condition presents many challenges to physicians in terms of classification, diagnosis, appropriate laboratory workup, and treatment. Moreover, it compels a careful follow-up. This article reviews the Chapel-Hill 2012 classification, etiology, recent insights in pathophysiology, some important dermatological clues for the diagnosis and summarizes treatment of some of these complex vasculitis syndromes.

Upregulation of intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 in renal tissue in severe dengue in humans: Effects on endothelial activation/dysfunction

Abstract INTRODUCTION: Dengue is an important mosquito-borne disease in tropical and subtropical regions. Adhesion molecules have not been systematically characterized in the renal tissue of patients with severe dengue (SD). The objective of this study was to detect viral antigens in samples from patients that evolved with SD, correlating with the expression of ICAM-1, VCAM-1, VE-cadherin, and E-selectin to contribute to a better understanding of the pathophysiology of SD. METHODS: Kidney specimens from patients with SD were selected according to clinical and laboratorial data and submitted to histological and immunohistochemistry analysis. A semiquantitative evaluation was performed considering positive immunostaining in 20 glomeruli. RESULTS: Viral antigens were mainly detected in distal tubules. The intense immunostaining of VCAM-1 and ICAM-1 was observed. The expression of E-selectin was discrete, and VE-cadherin expression varied from mild to moderate. VCAM-1 was slightly intense in the glomerular capsule; the expression of ICAM-1 was diffuse. E-selectin was diffuse, and VE-cadherin varied from mild to moderate. The most frequent histological findings were glomerular congestion, mild glomerulitis, acute renal injury, and glomerular atrophy. CONCLUSIONS: The results appear to demonstrate an imbalance between vascular endothelial permeability regulating events in renal lesions in SD. The increase in the expression of ICAM-1 and VCAM-1 is an in-situ indicator of higher permeability with a consequent influx of cells favoring the inflammation of the endothelium. These molecules are important in the pathophysiology of the disease and provide the possibility of developing new markers for the evaluation, clinical follow-up, and therapeutic response of patients with SD.

Toll-like recepoors (tlr) 2 and 4 expression ofkeratinocytes from patients witth localized and disseminated dermatopyytosis / Expressão de receptores do tipo Toll 2 e 4 nos queratinócitos de pacientes com dermatofitose localizada e disseminada

There are few studies on the role of innate immune response in dermatophytosis. An investigation was conducted to define the involvement of Toll-Like Receptors (TLRs) 2 and 4 in localized (LD) and disseminated (DD) dermatophytosis due to T. rubrum. Fifteen newly diagnosed patients, eight patients with LD and seven with DD, defined by involvement of at least three body segments were used in this study. Controls comprised twenty skin samples from healthy individuals undergoing plastic surgery. TLR2 and TLR4 were quantified in skin lesions by immunohistochemistry. A reduced expression of TLR4 in the lower and upper epidermis of both LD and DD patients was found compared to controls; TLR2 expression was preserved in the upper and lower epidermis of all three groups. As TLR4 signaling induces the production of inflammatory cytokines and neutrophils recruitment, its reduced expression likely contributed to the lack of resolution of the infection and the consequent chronic nature of the dermatophytosis. As TLR2 expression acts to limit the inflammatory process and preserves the epidermal structure, its preserved expression may also contribute to the persistent infection and limited inflammation that are characteristic of dermatophytic infections.

A literatura sobre o papel da resposta imune inata em dermatofitose é escassa. Este estudo se propôs a investigar a participação dos receptores do tipo Toll 2 e 4 (TLRs) 2 e 4 em pacientes com dermatofitose localizada (LD) e disseminada (DD, definida como lesões em pelo menos três segmentos corpóreos distintos), causadas por Trichophyton rubrum. Foram analisados cortes histológicos de 15 pacientes recém-diagnosticados, oito com LD e sete com DD. O grupo controle foi composto por 20 amostras de pele de indivíduos saudáveis submetidos a cirurgia plástica. TLR-2 e TLR-4 foram quantificados em lesões cutâneas por imunohistoquímica. Encontramos uma expressão reduzida de TLR-4 na epiderme superior e inferior nos dois grupos, LD e DD, quando comparados com o grupo controle; a expressão de TLR-2 foi preservada na epiderme superior e inferior de todos os três grupos. Como a sinalização por TLR-4 induz produção de citocinas inflamatórias e recrutamento de neutrófilos, a menor expressão desta molécula provavelmente contribui para a não resolução da infecção e conseqüente natureza persistente da dermatofitose. Como a sinalização via TLR-2 tem sido descrita como fator de regulação do processo inflamatório e de preservação da estrutura epidérmica, a sua expressão inalterada nas lesões dos pacientes com DD e DL pode contribuir também para a persistência da infecção e do reduzido processo inflamatório que são característicos das infecções por dermatófitos.

Immunoelectron microscopy study of superficial skin nerves in drug-induced acute urticaria / Estudo de microscopia imunoeletrônica dos nervos superficiais da pele na urticária aguda induzida por medicamentos

BACKGROUND: Few studies have evaluated the ultrastructure of the superficial skin nerves in urticaria. OBJECTIVE: The objective of this study was to describe findings in superficial skin nerves in cases of drug-induced acute urticaria. METHODS: Seven patients with drug-induced acute urticaria were included in the study. Skin biopsies were obtained from the urticarial lesion and from the apparently normal skin. The 14 fragments collected were processed for immunogold electron microscopy using single stains for antitryptase and anti-FXIIIa antibodies, as well as double immunogold labeling for both. RESULTS: Some sections showed mast cells in the process of degranulation. Following double immunogold staining, 10 nm (FXIIIa) and 15 nm (Tryptase) gold particles were found together throughout the granules in mast cells, indicating that tryptase and FXIIIa are located inside each one of the granules of these cells. Interestingly, we found strong evidence of the presence of tryptase and factor XIIIa in the superficial skin nerves of these patients, both in cases of urticarial lesions (wheals) and in the apparently normal skin. CONCLUSIONS: Tryptase and FXIIIa are present in the superficial nerves of the skin in drug-induced acute urticaria. This is the first report of tryptase and FXIIIa expression in the superficial skin nerves of patients with urticaria. Tryptase may be participating in neural activation in these patients, while FXIIIa may be present in the nerves to guarantee the functional integrity of structures.

FUNDAMENTOS: Poucos autores têm estudado a ultraestrutura dos nervos superficiais na urticária. OBJETIVO: Descrever os achados nos nervos cutâneos superficiais em casos de urticária aguda induzida por medicamentos. MÉTODOS: Sete pacientes com urticária aguda induzida por medicamentos foram incluídos no estudo. Foram obtidas biopsias da pele da lesão urticariforme e da pele aparentemente normal. Os 14 fragmentos coletados foram processados usando imunomarcação com ouro para anticorpos anti-triptase e anti-FXIIIa separadamente, além da dupla imunomarcação com ambos anticorpos. A seguir as amostras foram submetidas à análise por microscopia imunoeletrônica. RESULTADOS: Alguns cortes demonstraram mastócitos em processo de degranulação. Após a imunomarcação dupla, partículas de ouro de 10 nm (FXIIIa) e partículas de ouro de 15 nm (Triptase) apresentavam-se juntas em grânulos de mastócitos indicando que a triptase e o FXIIIa se localizam dentro de cada um dos grânulos dessas células. Curiosamente, foi encontrada uma forte evidência da presença da triptase e do fator XIIIa nos nervos superficiais dos pacientes avaliados, tanto em lesões urticadas, como na pele aparentemente normal. CONCLUSÕES: A triptase e o FXIIIa estão presentes nos nervos superficiais da pele na urticária aguda medicamentosa. Este é o primeiro relato da expressão de triptase e de FXIIIa nos nervos superficiais na urticária. A triptase poderia estar participando da ativação neural nos pacientes estudados. O FXIIIa poderia estar presente nos nervos, com a finalidade de manter a integridade funcional dessas estruturas.

Vasculopatia livedoide: uma doença cutânea intrigante / Livedoid vasculopathy: an intringuing cutaneous disease

A vasculopatia livedoide é uma afecção cutânea oclusiva dos vasos sanguíneos da derme, de caráter pauci-inflamatório ou não-inflamatório. Caracteriza-se pela presença de lesões maculosas ou papulosas, eritêmato-purpúricas, nas pernas, especialmente nos tornozelos e pés, as quais produzem ulcerações intensamente dolorosas, que originam cicatrizes atróficas esbranquiçadas, denominadas "atrofia branca". Nesta revisão, abordamos os estudos e relatos de caso da literatura médica referentes às associações etiopatogênicas da doença, particularmente as que se referem aos estados de trombofilia, seus achados histopatológicos e abordagens terapêuticas empregadas na difícil condução clínica destes casos.

Livedoid vasculopathy is a skin disease that occludes the blood vessels of the dermis. It has a pauciinflammatory or non-inflammatory nature. It is characterized by the presence of macular or papular, erythematous-purpuric lesions affecting the legs, especially the ankles and feet, and producing intensely painful ulcerations, which cause white atrophic scars called "atrophie blanche". This review includes studies and case reports found in the medical literature regarding the etiopathogenic associations of the disease, particularly those related to thrombophilia, their histopathological findings and the therapeutic approaches used in the difficult clinical management of these cases.

Nevo da epidermólise bolhosa: aspectos clínicos, dermatoscópicos e histológicos em um caso de portador da forma distrófica recessiva / Epidermolysis bullosa nevi: clinical, dermatoscopical and histological features in a case of recessive dystrofic form

As lesões melanocíticas adquiridas podem apresentar aspecto clínico não-usual em pacientes portadores de epidermólise bolhosa hereditária. Essas lesões são conhecidas como "nevos EB" e, muitas vezes, constituem um desafio diagnóstico ao dermatologista por apresentarem características clínicas, dermatoscópicas e histopatológicas semelhantes às encontradas no melanoma. Não são exclusivas de nenhuma forma de epidermólise bolhosa e têm sua frequência aumentada na infância. Relata-se o caso de um doente do sexo masculino, de 6 meses de idade, portador da forma distrófica recessiva da doença, com lesão pigmentada de rápido crescimento na coxa esquerda. Optou-se por seguimento clínico da lesão, considerando que os aspectos clínicos, dermatoscópicos e histológicos eram compatíveis com a descrição de outros casos de nevo EB previamente descritos.

Acquired melanocytic lesions may present unusual clinical features in all forms of hereditary epidermolysis bullosa. These lesions are known as "EB nevi", and often pose a diagnostic challenge for dermatologists given their resemblance - clinically, dermoscopically and histologically - to melanoma. The lesions have been reported in all types of hereditary EB, most of them in childhood. We report the case of a 6-month-old boy suffering from recessive dystrophic epidermolysis bullosa (RDEB) that presented as a large pigmented lesion on his left thigh. We decided to monitor the lesion closely since we considered that the clinical and pathological aspects of the lesion were compatible with the description of other previously reported cases of EB nevi.

Actinic lesions in fishermen's lower lip: clinical, cytopathological and histopathologic analysis

INTRODUCTION: Actinic cheilitis (AC) is considered to be a pre-malignant lesion or an incipient and superficial form of lip squamous cell carcinoma. It is commonly found in individuals whose occupational activities are related to chronic sun exposure and the definitive diagnosis is performed with biopsy. Althoug Exfoliative cytology has been used as a screening procedure to evaluate cancer of the oral cavity no studies have proposed the use of exfoliative cytologic analysis to evaluate and diagnose AC. OBJECTIVE: The purpose of this study was to evaluate lower lip lesions on fishermen related to chronic solar exposure using clinical, cytologic and histopathologic analyses. PATIENTS AND METHODS: Smears taken from the vermilion of the lower lips of 125 fishermen and 30 control individuals were subjected to cytologic analysis. RESULTS: The harvested cells were sufficient for cytologic analysis in 83.2 percent of the samples. Sixteen fishermen exhibited prominent lower lip lesions that justified biopsy and histological studies. In total, 4 specimens were malignant (3.2 percent), and 12 displayed epithelial dysplasia, demonstrating that the prevalence of epithelial dysplasia and malignant lesions was high among the fishermen population. These conditions were strongly associated with infiltration and blurring of the vermilion margin of the lower lip. CONCLUSION: The cytologic analysis was not useful for detecting epithelial dysplasia or malignant alterations.

Vasculites dos médios e grandes vasos: [revisão] / Medium and large vessel vasculitis: [revision]

As vasculites são constituídas por um grande grupo de síndromes caracterizadas por inflamação e necrose da parede dos vasos sangüíneos, resultando em estreitamento ou oclusão do lúmen. A distribuição dos vasos envolvidos varia consideravelmente e serve de base para a classificação das síndromes vasculíticas: grandes vasos (arterite de Takayasu, arterite temporal); pequenos e médios vasos (poliarterite nodosa, síndrome de Churg-Strauss, granulomatose de Wegener, vasculites nas doenças reumáticas); e pequenos vasos (vasculite de hipersensibilidade, púrpura de Henoch-Schonlein, poliangeíte microscópica, crioglobulinemia). Este artigo revisa as vasculites dos médios e grandes vasos e opções terapêuticas atuais; além de oferecer orientação sobre abordagem diagnóstica e tratamento dos pacientes com suspeita de vasculite cutânea.

Vasculitis comprises a broad group of syndromes characterized by inflammation and necrosis on thewalls of blood vessels, resulting in narrowing or occlusion of the lumen. The distribution of involved blood vesselvaries considerably and serves as the basis for one classification of vasculitic syndromes: large vessels (Takayasu arteritis, giant cell arteritis); medium and small muscular arteries (polyarteritis nodosa, Churg-Strausssyndrome, Wegener's granulomatosis, vasculitis in rheumatic diseases); and small vessels ("hypersensitivity" vasculitis, Henoch-Schonlein purpura, microscopic polyangiitis, cryoglobulinemia). This article reviews medium and large vessel vasculitis and current treatment options; it also presents a comprehensive approach to diagnosing and treating patients with suspected cutaneous vasculitis.

Cytokine profile in Montenegro skin test of patients with localized cutaneous and mucocutaneous leishmaniasis / Perfil de citocinas na intradermorreação de Montenegro em doentes de leishmaniose cutânea localizada e cutâneo-mucosa

American tegumentary leishmaniasis presents as two major clinical forms: localized cutaneous leishmaniasis (LCL) and mucocutaneous leishmaniasis (MCL). The immune response in leishmaniasis is efficiently evaluated by the response to Leishmania antigen through the Montenegro skin test (MST). Both LCL and MCL present positive response to MST, indicating that the patients present cell-mediated immunity against the parasite - Leishmania. In spite of the presence of immunity in MCL, this is not sufficient to stop disease progression and prevent resistance to treatment. In this study we demonstrated interleukin (IL) 2, 4, 5 and interferon (IFN) gamma expression in biopsies of MST of ten patients with American tegumentary leishmaniasis. The obtained results were compared between LCL (n = 5) and MCL (n = 5) patients. The MST of MCL patients displayed a higher expression of IL-2, IL-4 and IL-5, in comparison to LCL. There was no significant difference in IFN-gamma expression between groups. The obtained results suggest the role of IL-4 and IL-5 in the maintenance of the immunopathogenic mechanism of the destructive lesions that characterize MCL.

A leishmaniose tegumentar americana apresenta duas formas clínicas mais comuns: a leishmaniose cutânea localizada e a leishmaniose cutâneo-mucosa. A imunidade da leishmaniose é avaliada pela resposta ao antígeno Leishmania através da Intradermorreação de Montenegro. Estas duas formas apresentam resposta positiva, indicando que o paciente apresenta imunidade celular contra o parasita Leishmania. Apesar da presença da imunidade celular na leishmaniose cutâneo-mucosa, esta não é suficiente para barrar a progressão da doença e a resistência ao tratamento. Neste estudo, detectamos quatro citocinas por imunohistoquímica, IL-2, IL-4, IL-5 e IFN-gama nas biópsias da intradermorreação de Montenegro de pacientes com leishmaniose tegumentar americana (n = 10), cinco com leishmaniose cutânea e cinco com cutâneo-mucosa. Os resultados mostraram uma alta expressão significativa de IL-2, IL-4, IL-5 na leishmaniose cutâneo-mucosa comparada com a leishmaniose cutânea localizada, mas sem diferença significante na expressão do IFN-γ entre os grupos. Estes resultados sugerem a importância da participação da citocina IL-4 e IL-5 na manutenção do mecanismo imunopatogênico das lesões destrutivas da forma cutâneo-mucosa.

Vasculite cutânea de pequenos vasos: subtipos e tratamento - Parte II / Small vessel cutaneous vasculitis: subtypes and treatment - Part II

Vasculite cutânea de pequenos vasos refere-se a grupo de doenças geralmente caracterizado por púrpura palpável, causada por vasculite leucocitoclástica das vênulas pós-capilares. Vasculites podem variar em gravidade, podendo manifestar-se como doença autolimitada, com acometimento de único órgão, ou como doença sistêmica, acometendo múltiplos órgãos, e evoluir para quadro de falência de múltiplos órgãos e sistemas. Esse grupo de doenças apresenta-se como desafio para o dermatologista, incluindo classificação e diagnóstico, avaliação laboratorial, tratamento e a necessidade de seguimento cuidadoso. Neste artigo são revistos os subtipos de vasculites cutâneas dos pequenos vasos e as opções atuais de tratamento; apresenta-se também abordagem detalhada para o diagnóstico e o tratamento do paciente com suspeita de vasculite cutânea e sistêmica.

Small vessel cutaneous vasculitis refers to a group of disorders usually characterized by palpable purpura, caused by leukocytoclastic vasculitis of postcapillary venules. Vasculitis can range in severity from a self-limited single-organ disorder to a life-threatening disease with the prospect of multiple-organ failure. This group of diseases presents many challenges to the dermatologist, including classification and diagnosis, laboratory workup, treatment, and the need for careful follow-up. This article reviews the subtypes of small vessel cutaneous vasculitis and current treatment options; it also presents a comprehensive approach to diagnosing and treating the patient with suspected cutaneous and systemic vasculitis.

Vasculite cutânea de pequenos vasos: etiologia, patogênese, classificação e critérios diagnósticos - Parte I / Small vessel cutaneous vasculitis: etiology, pathogenesis, classification and diagnostic criteria - Part I

Vasculite é a inflamação da parede dos vasos. Pode variar em gravidade desde doença autolimitada de um único órgão até doença grave com risco de morte por falência de múltiplos órgãos. Existem várias causas, embora só se apresente por poucos padrões histológicos de inflamação vascular. Vasos de qualquer tipo e em qualquer órgão podem ser afetados, resultando em ampla variedade de sinais e sintomas. Diferentes vasculites com apresentações clínicas indistinguíveis têm evolução e tratamento muito diferentes. Essa condição representa desafio para o médico, incluindo classificação, diagnóstico, exames laboratoriais pertinentes, tratamento e seguimento adequado. Neste artigo são revistos a classificação, a etiologia, a patogênese e os critérios diagnósticos das vasculites cutâneas.

Vasculitis is an inflammation of vessel walls. It may range in severity from a self-limited disorder in one single organ to a life-threatening disease due to multiple-organ failure. It has many causes, although they result in only a few histological patterns of vascular inflammation. Vessels of any type in any organ can be affected, a fact that results in a broad variety of signs and symptoms. Different vasculitides with indistinguishable clinical presentations have very different prognosis and treatments. This condition presents many challenges to physicians in terms of classification, diagnosis, appropriate laboratory workup, treatment, and the need for careful follow-up. This article reviews the classification, etiology, pathology and diagnostic criteria of cutaneous vasculitis.

Estudo genético do gene p16 pela técnica de PCR-SSCP e expressão de proteína p16 em melanomas de mucosa oral e melanomas cutâneos / Genetic analysis of p16 gene by PCR-SSCP technique and protein p16 expression in oral mucosa and skin melanomas

FUNDAMENTOS: A deleção e mutação do gene CDKN2a que codifica um inibidor específico da ciclina dependente de quinase 4, a proteína p16, têm sido implicadas na tumorigênese do melanoma cutâneo. Entretanto, pouco se conhece sobre essas alterações genéticas em melanomas de mucosa oral. OBJETIVOS: Verificar a presença de alterações no gene p16 e sua expressão protéica em melanomas esporádicos orais e cutâneos. MATERIAL E MÉTODOS: Avaliaram-se 36 espécimes de melanoma primário (sete orais e 29 cutâneos). Analisaram-se três exons do gene p16, pela técnica da reação em cadeia da polimerase/polimorfismo conformacional de fita simples do DNA.Verificou-se a expressão tecidual de proteína p16 por técnica imuno-histoquímica. Relacionaram-se os resultados com a espessura dos melanomas cutâneos. RESULTADOS: Cinco dos sete melanomas orais e 17 dos 29 melanomas cutâneos apresentaram indício de alteração no gene p16. Alterações do exon 2 foram as mais freqüentes, sendo 19 casos nos produtos obtidos com o mesmo iniciador. Observou-se expressão tecidual de p16 em apenas um melanoma oral, em 10/13 (76,9 por cento) casos de melanoma cutâneo de espessura até 1mm e em sete de oito (87,5 por cento) casos de espessura superior a 1mm. CONCLUSÃO: A freqüência de indícios de alteração na análise genética de p16 nos melanomas de mucosa oral foi de 71,42 por cento e de 58,6 por cento nos cutâneos. É possível sugerir a participação de alterações do gene p16 na patogenia do melanoma esporádico de mucosa oral. Não houve relação da sugestão de alteração genética do gene p16 e de sua expressão tecidual com a espessura dos melanomas cutâneos de diferentes subtipos histológicos.

BACKGROUND: Deletion and mutation of gene CDKN2a, which encodes a specific inhibitor of cyclin-dependent kinase 4 (CDK4), the protein p16, has been regarded as related to cutaneous melanoma tumorigenesis. However, little is known about those alterations in oral mucosa melanomas. OBJECTIVES: To verify possible p16 gene mutations and its protein expression in sporadic melanomas in oral mucosa and skin. MATERIALS AND METHODS: 36 primary sporadic melanoma paraffin-embedded specimens (seven oral mucosa and 29 skin lesions) were subjected to molecular analysis of exons 1, 2 and 3 of p16 gene using polymerase chain reaction/single strand conformational polymorphism technique. p16 protein expression was demonstrated by an immunohistochemical technique. Data obtained were correlated with tumor thickness. RESULTS: Five out of seven oral melanomas, and 17 out of 29 skin lesions displayed signs of alteration in p16 gene molecular analysis. Alterations in exon 2 of p16 gene were the most frequent. Protein p16 expression was observed in only one oral melanoma and in 10/13 (76.9 percent) skin melanomas up to 1.0 mm-thick and in 7/8 (87.5 percent) lesions thicker than 1.0 mm. CONCLUSIONS: Frequency of alterations disclosed by p16 gene molecular analysis in oral mucosa melanomas was 71.42 percent and 58.6 percent in cutaneous lesions. The obtained data suggest that p16 gene alterations play a role in the pathogenesis of sporadic melanoma of the oral mucosa. Neither protein p16 expression, nor p16 gene alteration had correlation with tumor thickness.

Ação da pentoxifilina nos dendrócitos dérmicos FXIIIa de placas de psoríase / Effects of pentoxifylline on dermaldendrocytes FXIIIa using psoriasis plaques as a model

FUNDAMENTOS: Não há consenso sobre o papel dos dendrócitos dérmicos (DD) nos eventos fisiopatológicos nos períodos de exacerbação e de acalmia da doença. A pentoxifilina (PTX) é uma metilxantina que inibe vários mecanismos inflamatórios. OBJETIVO: Estudar os efeitos da PTX sobre os dendróticos dérmicos de placas de psoríase com técnicas imuno-histoquímicas. MATERIAL E MÉTODOS: Trinta biópsias de placas de psoríase antes e após oito semanas de uso oral diário de 1.200mg de PTX foram incubadas com anticorpo primário de coelho antiFator XIIIa e anticorpo de ligação conjugado com fosfatase alcalina. RESULTADOS: As células imunomarcadas Fator XIIIa+ foram proeminentes com morfologia dendrítica arborescente na derme papilar formando linha celular logo abaixo da epiderme e exibindo arranjo nodular ao redor dos vasos. Após tratamento, as células apresentaram-se com morfologia dendrítica e fusiforme, distribuídas ao redor dos vasos da derme papilar e predominantemente fusiformes dispostas paralelamente à junção dermoepidérmica retificada. CONCLUSÕES: A PTX promove aumento do fluxo sangüíneo e diminuição da adesividade endotelial, com aumento dos mastócitos e DD FXIIIa. A PTX inibe o TNF-alfa, que implica a diminuição da expressão de receptores pelos DDs, como CCR7 e a manutenção do estímulo tecidual para sinalização e migração dos precursores, uma vez que os processos etiopatogenéticos não são afetados pela droga.

BACKGROUND: There is no consensus about dermal dendrocytes (DD) function on physiopathological events on psoriasis. Pentoxifylline (PTX) is a methylxanthine that inhibits many inflammatory mechanisms. OBJECTIVE: The aim was to evaluate PTX effect on DD proliferation of psoriasis through immunohistochemical techniques. MATERIAL AND METHODS: Thirty psoriatic skin specimens before and 8 weeks after 1200mg/day PTX were incubated with primary rabbit antibody anti-factor XIIIa and binding antibody conjugated with alkaline phosphatasis. RESULTS: Factor XIIIa+ DD were prominent with large cytoplasm and markedly dendritic morphology. They were present in a diffuse manner in the papillary dermis and around vessels. After PTX they became oval with scarce cytoplasm, showed no dendritic extensions, and were only present in some papillary bodies. CONCLUSION: PTX pharmacological action promotes vessel flow enhancement, endothelial cell adhesivity decrease, and mast cells and DD factor XIIIa+ increase. PTX has an inhibitory action on TNF alpha, which could imply in a decrease of DD receptor expression, as CCR7, and maintenance of the tissular stimulus to signalization and migration of precursors, since the etiopathogenic processes would not be affected by the drug.

Dendrócitos dérmicos fator XIIIa positivos na resposta tecidual cutânea da leishmaniose tegumentar americana / Factor XIIIa positive dermal dendrocytes in american tegumentary leishmaniasis cutaneous tissue response

Para verificar a participação dos dendrócitos dérmicos fator XIIIa positivos (DDFXIIIa+) na patogenia da leishmaniose tegumentar americana (LTA) fez-se a sua demonstração por técnica imuno-histoquímica em lesões de pele de 47 doentes e comparação de sua população com a de grupo controle normal. Verificou-se a interação dos DDFXIIIa+ com os parasitas por técnica imuno-histoquímica de dupla marcação com os anticorpos anti-fator XIIIa e anti-Leishmania. Os DDFXIIIa+ eram hipertróficos e numerosos nas lesões de LTA quando comparados a pele normal. Evidenciou-se parasitismo de DDFXIIIa+ em 11 de 22 casos. Os resultados sugerem a participação dos DDFXIIIa+ no mecanismos patogenéticos da LTA como célula - alvo, efetora e/ou apresentadora de antígenos / In order to verify factor XIIIa positive dermal dendrocyte (FXIIIa+DD) involvement in american tegumentary leishmaniasis pathogenesis, 47 patients skin lesions were subjected to immunohistochemistry technique, quantified and compared to a normal skin group sample. Interaction of FXIIIa+DD and parasites was disclosed by double-staining technique with anti-factor XIIIa and anti- Leishmania antibodies. FXIIIa+DD were hypertrofic and numerous in leishmaniasis skin lesions. FXIIIa+DD harboring Leishmania were observed in 11 of 22 biopsies. The results obtained suggest the participation of FXIIIa+DD in the pathogenesis of tegumentary leishmaniasis skin lesions as host cell, immune effector and/or antigen-presenting cell...