Action time and feed frequency of Lactobacillus plantarum for Nile tilapia / Tempo de ação e frequência alimentar do Lactobacillus plantarum para tilápia-do-nilo

O objetivo desta pesquisa foi avaliar o tempo de ação do Lactobacillus plantarum no trato intestinal, assim como em qual frequência esse probiótico deve ser oferecido para tilápia-do-nilo (Oreochomis niloticus). Quarenta e oito tilápias foram alimentadas com ou sem probiótico, durante 14 dias. Após esse período, os peixes foram esviscerados, e amostras do trato intestinal foram semeadas em ágar TCBS, cetrimide e MRS. Esse procedimento foi repetido dois, quatro e seis dias após o 14º dia. Depois disso, 252 tilápias foram divididas em quatro tratamentos, peixes alimentados com probiótico suplementado em 100%, 50%, 25% e 0% (controle) das alimentações. Após nove semanas, os índices zootécnicos foram avaliados. No dia zero, verificou-se maior concentração de bactérias ácido-lácticas e menor concentração de Vibrios spp. e de Pseudomonas spp. no trato intestinal dos alevinos alimentados com probiótico. Peixes alimentados com 100% e 50% das alimentações suplementadas com probiótico apresentaram melhores índices zootécnicos que os peixes alimentados com 25% de suplementação e sem suplementação. O L. plantarum atuou por quatro dias após a última alimentação, e, para obter os melhores índices, essa cepa deve ser suplementada em 50% das alimentações por dia para tilápia-do-nilo (O. niloticus).(AU)

FANCD2 Western blot as a diagnostic tool for Brazilian patients with Fanconi anemia

Fanconi anemia is a rare hereditary disease showing genetic heterogeneity due to a variety of mutations in genes involved in DNA repair pathways, which may lead to different clinical manifestations. Phenotypic variability makes diagnosis difficult based only on clinical manifestations, therefore laboratory tests are necessary. New advances in molecular pathogenesis of this disease led researchers to develop a diagnostic test based on Western blot for FANCD2. The objective of the present study was to determine the efficacy of this method for the diagnosis of 84 Brazilian patients with Fanconi anemia, all of whom tested positive for the diepoxybutane test, and 98 healthy controls. The FANCD2 monoubiquitinated isoform (FANCDS+/FANCD2L-) was not detected in 77 patients (91.7 percent). In 2 patients (2.4 percent), there was an absence of both the monoubiquitinated and the non-ubiquitinated proteins (FANCD2S-/FANCD2L-) and 5 patients (5.9 percent) had both isoforms (FANCD2S+/FANCD2L+). This last phenotype suggests downstream subtypes or mosaicism. All controls were diepoxybutane negative and were also negative on the FANCD2 Western blot. The Western blot for FANCD2 presented a sensitivity of 94 percent (79/84) and specificity of 100 percent (98/98). This method was confirmed as an efficient approach to screen Brazilian patients with deleterious mutations on FANCD2 (FANCD2S-/FANCD2L-) or other upstream genes of the FA/BRCA pathway (FANCDS+/FANCD2L-), to confirm the chromosome breakage test and to classify patients according to the level of FA/BRCA pathway defects. However, patients showing both FANCD2 isoforms (FANCD2S+/FANCD2L+) require additional studies to confirm mutations on downstream Fanconi anemia genes or the presence of mosaicism.

Allogeneic hematopoietic stem cell transplantation from an alternative stem cell source in Fanconi anemia patients: analysis of 47 patients from a single institution

We transplanted 47 patients with Fanconi anemia using an alternative source of hematopoietic cells. The patients were assigned to the following groups: group 1, unrelated bone marrow (N = 15); group 2, unrelated cord blood (N = 17), and group 3, related non-sibling bone marrow (N = 15). Twenty-four patients (51 percent) had complete engraftment, which was not influenced by gender (P = 0.87), age (P = 0.45), dose of cyclophosphamide (P = 0.80), nucleated cell dose infused (P = 0.60), or use of anti-T serotherapy (P = 0.20). Favorable factors for superior engraftment were full HLA compatibility (independent of the source of cells; P = 0.007) and use of a fludarabine-based conditioning regimen (P = 0.046). Unfavorable factors were > or = 25 transfusions pre-transplant (P = 0.011) and degree of HLA disparity (P = 0.007). Intensity of mucositis (P = 0.50) and use of androgen prior to transplant had no influence on survival (P = 0.80). Acute graft-versus-host disease (GVHD) grade II-IV and chronic GVHD were diagnosed in 47 and 23 percent of available patients, respectively, and infections prevailed as the main cause of death, associated or not with GVHD. Eighteen patients are alive, the Kaplan-Meyer overall survival is 38 percent at ~8 years, and the best results were obtained with related non-sibling bone marrow patients. Three recommendations emerged from the present study: fludarabine as part of conditioning, transplant in patients with <25 transfusions and avoidance of HLA disparity. In addition, an extended family search (even when consanguinity is not present) seeking for a related non-sibling donor is highly recommended.

Frequency of Fanconi anemia in Brazil and efficacy of screening for the FANCA 3788-3790del mutation

Fanconi anemia (FA) is an autosomal recessive genetic disease characterized by progressive bone marrow failure, susceptibility to cancer and multiple congenital anomalies. There is important clinical variability among patients and the knowledge of factors which might predict outcome would greatly help the decision making regarding the choices of treatment and the appropriate time to start it. Future studies of the possible correlation between specific mutations with specific clinical presentations will provide the answer to one of these factors. At our Center we standardized a rapid and precise screening test using a mismatch PCR assay for a specific mutation (3788-3790del in exon 38 of gene FANCA) in Brazilian FA patients. We present the results obtained after screening 80 non-consanguineous FA patients referred from all regions of Brazil with a clinical diagnosis of FA supported by cellular hypersensitivity to diepoxybutane. We were able to detect the 3788-3790del allele in 24 of the 80 (30 percent) FA patients studied. Thirteen of the 80 (16.25 percent) were homozygotes and 11 of the 80 (13.75 percent) were compound heterozygotes, thus confirming the high frequency of the FANCA 3788-3790del mutation in Brazilian FA patients. The identification of patients with specific mutations in the FA genes may lead to a better clinical description of this condition, also providing data for genotype-phenotype correlations, to a better understanding of the interaction of this specific mutation with other mutations in compound heterozygote patients, and ultimately to the right choices of treatment for each patient with improvement of the prognosis on future studies.