Linfoma burkitt-like em um lactente: relato de caso

Os linfomas não Hodgkin da infância, incluindo os linfomas de Burkitt e Burkitt-like são raros em lactentes. Um caso de linfoma não Hodgkin B em uma lactente de 13 meses de idade é descrito. Ao diagnóstico a paciente apresentava extenso comprometimento abdominal associado à ascite, derrame pleural e síndrome de lise tumoral. A análise imunofenotípica mostrou um fenótipo compatível com células linfóides oriundas do centro germinativo e a origem clonal dessas células foi demonstrada por reação em cadeia da polimerase. Não foi demonstrada associação do linfoma com infecção pelo vírus Epstein-Barr e/ou virus da imunodeficiência adquirida. O caso apresentado enfatiza a necessidade de considerar o diagnóstico de linfoma mesmo em lactentes.Childhood non-Hodgkin's lymphomas, including Burkitt and Burkitt-like, are rarely diagnosed in infants. A case of B-cell lymphoma in a 13-month-old girl with extensive abdominal disease, ascites, pleural effusion, and tumor lysis syndrome is reported. Phenotypic analysis showed a germinal center B-cell phenotype, and a B-cell clonality was confirmed by polymerase chain reaction. There was no evidence of Epstein-Barr and HIV infection. The case herein reported emphasizes the need for considering the diagnosis of lymphoma even in very young children

p53 gene analysis in childhood B non - Hodgkin's lymphoma

CONTEXTO: Alterações do gene supressor de tumor p53, como mutações e deleções, são lesões genéticas encontradas com maior freqüência nas neoplasias humanas, incluindo câncer de mama, pulmão e cólon. Entre as malignidades hematológicas, o gene 53 é freqüentemente mutado no linfoma de Burkitt, sendo detectadas mutações em 30-40% das amostras tumorais e em 70% das linhagens celulares. OBJETIVO: Analisar as alterações do gene p53 em crianças com linfoma não-Hodgkin de origem B. TIPO DE ESTUDO: Estudo descritivo. LOCAL: Centro de Oncologia Terciário. PARTICIPANTES: O estudo analisou 12 pacientes com linfoma não-Hodgkin B classificados como linfoma de Burkitt. A análise de possíveis mutações do gene p53 foi realizada pela técnica de PCR-SSCP dos exons 5, 6 ,7 e 8/9 do gene. RESULTADOS: Um padrão anormal de migração foi observado em quatro pacientes (33.3%), em um paciente no exon 6 e em três no exon 7. Os casos positivos incluíam dois pacientes que evoluíram para o óbito por progressão da doença. CONCLUSÃO: Esses resultados preliminares sugerem que as alterações do gene p53 são freqüentes em crianças com linfoma de Burkitt e podem contribuir para patogênese ou progressão da doença.CONTEXT: Mutations or deletions in the tumor-suppressor gene p53 are among the commonest genetic changes found in human neoplasms including breast, lung and bowel cancers. In hematological malignancies, p53 is most often mutated in Burkitt's lymphoma, with p53 mutations present in 30 to 40% of tumor samples and in 70% of cell lines. OBJECTIVE: To analyze the p53 gene alterations in child patients with B non-Hodgkin's lymphoma. DESIGN: Descriptive study. SETTING: Tertiary oncology care center. PARTICIPANTS: The study investigated 12 patients with childhood B non-Hodgkin's lymphoma (Burkitt's lymphoma). Screening for p53 mutations was done by polymerase chain reaction - single strand conformational polymorphism (PCR-SSCP) analysis of exon 5 to 8/9 of the gene. RESULTS: Abnormal polymerase chain reaction - single strand conformational polymorphism migration pattern was observed in 4 patients (33.3%), one on exon 6 and three on exon 7. Positive cases included 2 patients who died from disease. CONCLUSION: These preliminary results suggest that p53 mutations are quite frequent in children with Burkitt's lymphoma and may play a role in lymphoma genesis or disease progression

p53 gene analysis in childhood B non - Hodgkin's lymphoma

CONTEXT: Mutations or deletions in the tumor-suppressor gene p53 are among the commonest genetic changes found in human neoplasms including breast, lung and bowel cancers. In hematological malignancies, p53 is most often mutated in Burkitt's lymphoma, with p53 mutations present in 30 to 40% of tumor samples and in 70% of cell lines. OBJECTIVE: To analyze the p53 gene alterations in child patients with B non-Hodgkin's lymphoma. DESIGN: Descriptive study. SETTING: Tertiary oncology care center. PARTICIPANTS: The study investigated 12 patients with childhood B non-Hodgkin's lymphoma (Burkitt's lymphoma). Screening for p53 mutations was done by polymerase chain reaction - single strand conformational polymorphism (PCR-SSCP) analysis of exon 5 to 8/9 of the gene. RESULTS: Abnormal polymerase chain reaction - single strand conformational polymorphism migration pattern was observed in 4 patients (33.3%), one on exon 6 and three on exon 7. Positive cases included 2 patients who died from disease. CONCLUSION: These preliminary results suggest that p53 mutations are quite frequent in children with Burkitt's lymphoma and may play a role in lymphoma genesis or disease progression

The Synthetic Peptide LyeTx I mn∆K, Derived from <i>Lycosa erythrognatha</i> Spider Toxin, Is Active against Methicillin-Resistant <i>Staphylococcus aureus</i> (MRSA) In Vitro and In Vivo

The urgent global health challenge posed by methicillin-resistant Staphylococcus aureus (MRSA) infections demands effective solutions. Antimicrobial peptides (AMPs) represent promising tools of research of new antibacterial agents and LyeTx I mn∆K, a short synthetic peptide based on the Lycosa erythrognatha spider venom, is a good representative. This study focused on analyzing the antimicrobial activities of LyeTx I mn∆K, including minimum inhibitory and bactericidal concentrations, synergy and resensitization assays, lysis activity, the effect on biofilm, and the bacterial death curve in MRSA. Additionally, its characterization was conducted through isothermal titration calorimetry, dynamic light scattering, calcein release, and finally, efficacy in a mice wound model. The peptide demonstrates remarkable efficacy against planktonic cells (MIC 8–16 µM) and biofilms (>30% of inhibition) of MRSA, and outperforms vancomycin in terms of rapid bactericidal action and anti-biofilm effects. The mechanism involves significant membrane damage. Interactions with bacterial model membranes, including those with lysylphosphatidylglycerol (LysylPOPG) modifications, highlight the versatility and selectivity of this compound. Also, the peptide has the ability to sensitize resistant bacteria to conventional antibiotics, showing potential for combinatory therapy. Furthermore, using an in vivo model, this study showed that a formulated gel containing the peptide proved superior to vancomycin in treating MRSA-induced wounds in mice. Together, the results highlight LyeTx I mnΔK as a promising prototype for the development of effective therapeutic strategies against superficial MRSA infections