Glucocerebrosidase deficiency in zebrafish affects primary bone ossification through increased oxidative stress and reduced Wnt/\u3b2-catenin signaling.

Loss of lysosomal glucocerebrosidase (GBA1) function is responsible for several organ defects, including skeletal abnormalities in type 1 Gaucher disease (GD). Enhanced bone resorption by infiltrating macrophages has been proposed to lead to major bone defects. However, while more recent evidences support the hypothesis that osteoblastic bone formation is impaired, a clear pathogenetic mechanism has not been depicted yet. Here, by combining different molecular approaches, we show that Gba1 loss of function in zebrafish is associated with defective canonical Wnt signaling, impaired osteoblast differentiation and reduced bone mineralization. We also provide evidence that increased reactive oxygen species production precedes the Wnt signaling impairment, which can be reversed upon human GBA1 overexpression. Type 1 GD patient fibroblasts similarly exhibit reduced Wnt signaling activity, as a consequence of increased \u3b2-catenin degradation. Our results support a novel model in which a primary defect in canonical Wnt signaling antecedes bone defects in type 1 G

T-cell large granular lymphocytic leukemia: treatment experience with fludarabine

OBJECTIVES: The aim of this retrospective study was to investigate the results of T-cell large granular lymphocytic leukemia treatment with fludarabine by assessing the complete hematologic response, the complete molecular response, progression-free survival, and overall survival. METHODS: We evaluated the records of six patients with T-cell large granular lymphocytic leukemia who were treated with fludarabine as a first-, second-, or third-line therapy, at a dose of 40 mg/m(2), for three to five days per month and 6 to 8 cycles. RESULTS: Of the six patients investigated with T-cell large granular lymphocytic leukemia who were treated with fludarabine, five (83.3%) were female, and their median age was 36.5 years (range 18 to 73). The median lymphocyte level was 3.4×10(9)/L (0.5 to 8.9). All patients exhibited a monoclonal T-cell receptor gamma gene rearrangement at diagnosis. Two (33.3%) patients received fludarabine as first-line treatment, two (33.3%) for refractory disease, one (16.6%) for relapsed disease after the suspension of methotrexate treatment due to liver toxicity, and one (16.6%) due to dyspesia. A complete hematologic response was achieved in all cases, and a complete molecular response was achieved in five out six cases (83.3%). During a mean follow-up period of 12 months, both the progression-free survival and overall survival rates were 100%. CONCLUSION: T-cell large granular lymphocytic leukemia demonstrated a high rate of complete hematologic and molecular response to fludarabine, with excellent compliance and tolerability rates. To confirm our results in this rare disease, we believe that fludarabine should be tested in clinical trials as a first-line treatment for T-cell large granular lymphocytic leukemia

Outcomes of HIV-associated Burkitt Lymphoma in Brazil: high treatment toxicity and refractoriness rates – a multicenter cohort study

Although the increased use of combined antiretroviral therapy (cART) has decreased the incidence of lymphomas HIV-associated, Burkitt lymphoma (BL) incidence remains stable. Reported outcomes on HIV-associated BL from developed countries seem to corroborate that the regimens do not need to be tailored to the HIV-positive population. Materials and methods: This is a retrospective multicenter cohort study from Brazil, including HIV-positive patients aged 15 years and above diagnosed with BL. Results: A total of 54 patients were included. Median age was 39 years (range, 15–64). At diagnosis, advanced disease was found in 86% and 52% had a CD4+ count lower than 200 cells/mm3. Five patients died before starting any regimen. Among the remaining 49 patients, most were treated with Hyper-CVAD (53%) and CODOX-M IVAC (18%). Rituximab was used in frontline in only 16% of the patients. Primary refractory disease was found in 14%. A treatment-related mortality of 38.7% and a complete response rate of 44.9% were found. At 4 years, estimated overall survival (OS) was 39.8%. All relapsed and primary refractory patients eventually died. Remaining patients died from infections (24/34), despite antimicrobial prophylaxis and associated cART. Conclusion: Early mortality and toxicity were higher in our cohort than in developed countries. A faster diagnosis, better understanding of the biology of the disease, establishment of low toxicity regimens, inclusion of rituximab and improvement of supportive care may decrease the mortality of HIV-associated BL in developing countries89sem informaçãosem informaçã

Linfoma primário de células T no líquido cefalorraquidiano de cão: relato de caso

Relata-se o diagnóstico de linfoma primário no sistema nervoso central em um cão Labrador Retrievier, de 10 anos de idade, que apresentava episódios convulsivos, incoordenação nos membros posteriores, head tilt, ataxia e sensibilidade diminuída no lado esquerdo. Constataram-se alterações laterais esquerdas, como ausências de propriocepção e de posicionamento tátil, alterações posteriores nas provas de carrinho de mão e de reação ao pulo e diminuição da extensão da postura e hemilocomoção. No líquido cefalorraquidiano (LCR), houve predomínio de linfócitos atípicos, caracterizados pela presença de anisocitose e anisocariose, nucléolos evidentes e anisonucleose, basofilia e microvacuolização citoplasmáticas, mitoses atípicas e corpúsculos linfoglandulares, compatíveis com linfoma, confirmado pelo exame histológico e imunocitoquímico, o qual revelou origem T, com expressão CD3+ e CD79-. A tomografia computadorizada não foi conclusiva e evidenciou diversas áreas hipodensas e intensificação de contraste na região de sulcos e giros do parênquima encefálico. A coleta do LCR foi essencial na rapidez do diagnóstico definitivo, indicando a natureza rara desta lesão primária