RESUMO
An elegant, efficient, and highly regioselective approach for the synthesis of novel methyl 5-amino-3-(methylthio)-1-differently substituted-1H-pyrazole-4-carboxylates is reported. The procedure involves the cyclocondensation of α-oxeketene S, S-dimethyl acetal building blocks with different alkyl, aryl, and heterocyclic acid hydrazides. The novel molecules were obtained in good yields and their identities confirmed by NMR and HRMS spectrometry.
Assuntos
Acetais/química , Etilenos/química , Hidrazinas/química , Cetonas/química , Nitrogênio/química , Pirazóis/química , Pirazóis/síntese química , Técnicas de Química Sintética , EstereoisomerismoRESUMO
BACKGROUND: Hypopigmented mycosis fungoides (HMF) is a rare subtype of mycosis fungoides (MF). We compared patients with exclusive hypopigmented lesions with a group of MF patients with concomitant different lesions. METHODS: 20 patients with HMF only and 14 patients with hypopigmented lesions concomitant with other types of lesions (mixed MF, MMF) were selected. Clinical-epidemiological analysis as well as histological and immunohistochemical studies were performed. RESULTS: HMF and MMF preserve some similarities, like predilection for dark-skinned persons and slow progression, but they also present differences: the exclusive variant is associated with early onset and a clear CD8+ immunophenotype, whereas MMF patients tend to present a predominance of CD4+ cell infiltrates. Histological analysis revealed similar findings; relapsing courses were common. CONCLUSION: Whether patients are suffering from exclusive HMF or MMF, the presence of hypopigmented lesions can be considered a marker of good prognosis in MF, since both groups presented similar data, such as staging and disease duration.
Assuntos
Hipopigmentação/patologia , Micose Fungoide/patologia , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Idoso , Biópsia por Agulha , Criança , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Hipopigmentação/diagnóstico , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Micose Fungoide/diagnóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Neoplasias Cutâneas/diagnóstico , Estatísticas não Paramétricas , Adulto JovemRESUMO
BACKGROUND: Hypopigmentation in hypopigmented mycosis fungoides (MF) is thought to result from the action of CD8+ cells on melanocytes. Here, we investigated the immunophenotype and melanocytic markers in hypopigmented MF lesions. METHODS: Specimens of hypopigmented lesions and normal skin from 18 patients with hypopigmented MF and specimens of non-hypopigmented lesions from 8 patients with classic/conventional MF were subjected to neoplastic immunophenotyping and melanocyte immunostaining with Melan-A, tyrosinase, stem cell factor receptor (CD117) and microphthalmia-associated transcription factor (MiTF). RESULTS: The CD8+ immunophenotype was more common in hypopigmented MF lesions (14/18) than in conventional MF lesions (1/8, p = 0.0033). There was a main effect of specimen type (hypopigmented MF lesion, hypopigmented MF normal skin, conventional MF lesion) on the number of melanocytes stained with Melan-A (median number/mm basal membrane, 1.97 vs. 4.77 vs. 5.42, respectively, p = 0.0046), tyrosinase (2.19 vs. 4.02 vs. 5.26, p = 0.0114), CD117 (4.29 vs. 7.81 vs. 5.45, p = 0.0064), and MiTF (2.75 vs. 4.43 vs. 4.98, p = 0.005). CONCLUSIONS: These results confirm previous findings of fewer melanocytes and CD117-positive melanocytes in hypopigmented MF and showed reduced MiTF identification, which is crucial for the function and survival of melanocytes. Thus cytotoxic CD8+ cell action may determine CD117/MiTF dysfunction, causing hypopigmentation.