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Based on morphological and molecular phylogenetic markers and the fertility of sexual crosses, two novel species of Fusarium associated with Dactylopius opuntiae (Hemiptera: Dactylopiidae) and Aleurocanthus woglumi (Hemiptera: Aleyrodidae) from northeastern Brazil are described as Fusarium caatingaense and F. pernambucanum. Partial sequences of five loci were generated for 29 entomopathogenic Fusarium isolates. Multilocus phylogenetic analyses demonstrated that F. caatingaense and F. pernambucanum belong to the Incarnatum clade of the Fusarium incarnatum-equiseti species complex (FIESC). These species displayed common morphological characters such as the production of various types of aerial conidia formed on monophialides and polyphialides and differ from each other mainly in the dimensions and morphology of their sporodochial conidia. Mating type polymerase chain reaction (PCR) revealed 17 MAT1-1 isolates and 12 MAT1-2 isolates, all of them heterothallic. Fertile perithecia were produced in 4.2% of infraspecific crosses of F. caatingaense and in 13.3% of infraspecific crosses of F. pernambucanum after 2-3 wk. Crosses between F. caatingaense and F. pernambucanum did not result in fertile perithecia. We demonstrate the existence of a sexual stage in species of the Incarnatum clade and describe the morphological characters of these sexual morphs for the first time. These results suggest that previously unknown sexual cycles contribute to the high genetic diversity within FIESC.

Fusarium tupiense, the main causal agent of mango malformation in Brazil, is described through a combination of morphological, biological and molecular markers. This new species belongs to the Gibberella fujikuroi species complex (GFSC) and has an anamorph morphologically similar to Fusarium mangiferae and F. sterilihyphosum. F. tupiense can be differentiated from other species in the G. fujikuroi species complex on the basis of sexual crosses, amplified fragment length polymorphism (AFLP) markers and partial sequences of the tef1 and tub2 genes. Female fertility for field isolates of F. tupiense appears to be low. PCR with primers specific for the mating type (MAT) alleles and sexual crosses identified this species as heterothallic with two idiomorphs. Female-fertile tester strains were developed for the identification of field strains of this species through sexual crosses.

We examined the influence of the glutathione S-transferase mu 1 (GSTM1), theta 1 (GSTT1), and pi 1 (GSTP1) polymorphisms, which are involved in the metabolism of alkylating agents and anthracyclines, on the outcome of patients with Hodgkin lymphoma (HL) treated with conventional chemotherapy. Genomic DNA from 125 consecutive cases was analyzed by polymerase chain reaction and enzymatic digestion for polymorphism determination. The GSTM1 undeleted genotype was associated with more advanced tumor stage and worse disease-free survival. The GSTT1 undeleted genotype was associated with higher recurrence rate. In contrast, higher toxicity of chemotherapy was attributed to absence of the GSTT1 gene. Concerning overall survival, lower tumor stage (p = 0.006) and International Prognostic Score (p = 0.02), lower peripheral leukocyte count (p = 0.0003), higher serum albumin level (p = 0.08), and GSTT1 undeleted genotype (p = 0.04) were predictive of a better outcome of patients. In multivariate analysis comparing staging and GST polymorphism, only tumor stage and GSTT1 genotype remained in the model. Our results suggest that the GSTT1 polymorphism influences the outcome of Brazilian patients with HL. However, studies of toxicity, pharmacokinetics, and protein function may clarify whether carriers of the distinct genotypes should receive different doses of chemotherapeutic agents.

We tested in this study whether the polymorphisms of the glutathione S-transferase Mu1 (GSTM1), glutathione S-transferase Theta 1 (GSTT1) and glutathione S-transferase Pi 1 (GSTP1), involved in metabolism of chemical agents, cell proliferation and cell survival, alter the risk for Hodgkin lymphoma (HL). Genomic DNA from 110 consecutive patients with HL and 226 controls was analysed by polymerase chain reaction and restriction digestion for the polymorphism analyses. Similar frequencies of the GSTM1 and GSTT1 genotypes were seen in patients and controls. In contrast, the frequency of the GSTP1 wild genotype (59.1%versus 36.3%, P = 0.004) was higher in patients than in controls. Individuals with the wild genotype had a 2.68 (95%CI: 1.38-5.21)-fold increased risk for the disease than others. An excess of the GSTP1 wild genotype was also observed in patients with tumors of stages III + IV when compared with those with tumors of stages I + II (39.1%versus 20.0%, P = 0.03). These results suggest that the wild allele of the GSTP1 gene is linked to an increased risk and high aggressiveness of the HL in our cases but they should be confirmed by further studies with larger cohorts of patients and controls.

Introduction: Angiotensin-converting enzyme inhibitors (ACEi) have been successfully used for patients with cardiac dysfunction after myocardial infarction., Objective: The aim of the present study was to investigate cardiac effects of ACEi in sickle cell disease (SCD) patients, as there are no previous reports regarding these effects., Methods: Enalapril was administered to 9 SCD patients with microalbuminuria. Nine SCD patients without microalbuminuria, matched according to age, diagnosis and levels of haemoglobin, haematocrit and foetal haemoglobin did not receive enalapril and were followed up as the control group during the same period of study. Echocardiograms were performed before the study entry and after 36 months of follow-up., Results: At 36 months of follow-up, significant increases in left ventricular mass, left ventricular mass index, posterior left ventricular wall thickness in end-diastole, interventricular septal wall thickness in end-diastole, and aortic root diameter values were seen in untreated, but not in enalapril-treated patients. No major changes were seen in left ventricular systolic diameter, diastolic dimension and ejection fraction, and left atrial diameter, in both groups, along the observational period., Conclusion: The results of this study suggest that enalapril prevents cardiac remodelling in SCD patients. However, a large trial concerning the response to enalapril in patients with SCD should be carried out to further clarify this issue.

Point mutations affecting codons 12, 13 (exon 1) and 61 (exon 2) of the N-RAS gene and codons 12 and 13 (exon 1) of the K-RAS gene are identified in approximately 30.0% and 10.0%, respectively, of multiple myeloma (MM) patients living in the northern hemisphere. To date, there are no reports about the prevalence of RAS gene mutations in MM Brazilian patients, and this comprised the aim of the present study. DNA from bone marrow aspirates of 252 patients with MM (139 males and 113 females; aged 59.33 +/- 11.95 years) were investigated for whole exons 1 and 2 of the N-RAS gene and whole exon 1 of the K-RAS gene by direct sequencing of DNA amplified in vitro by the polymerase chain reaction. Fifty-three out of 252 (21.03%) MM patients presented RAS mutations. Heterozygous mutations at codons 4, 10 (exon 1), 61 and 65 (exon 2) of the N-RAS gene were identified in seven out of 252 (2.78%) patients. K-RAS heterozygous mutations at codons 7, 12, 13 (exon 1) were seen in 46 out of 252 (18.25%) patients. To the best of our knowledge, the mutation at codon 7 of K-RAS gene is reported for the first time in MM. Taken together, these results suggest that Brazilian MM patients are characterized by: (i) a low prevalence of RAS mutation and (ii) RAS mutations located at distinct regions of the critical codons of the N-RAS and K-RAS genes.

The role of apoptosis in the pathobiology of myelodysplastic syndromes (MDS) remains controversial. We studied the expression of CD95 and CD95L in CD34+ cells of patients with newly diagnosed MDS by flow cytometry, and examined the relation between this expression and FAB and WHO types, total number of CD34+ bone marrow (BM) cells and the degree of peripheral cytopenias. The patients with refractory anemia (RA) and sideroblastic anemia showed CD34+ cells in numbers comparable to normal donors, but had a higher percentage of CD95/CD34 and CD95L/CD34 positive cells. An inverse correlation was found between these cells and the total CD34+ cells. This was also observed when only patients with RA were analyzed. In RAEB, however, CD95/CD95L expression correlated with CD34+ cells but not with the percentage of BM blasts. After classification by the WHO proposal, the patients with refractory cytopenias with multilineage dysplasia showed features intermediary between RA and RAEB. No significant correlation was seen between the expression of CD95/CD95L and the peripheral blood counts. These results are in keeping with the hypothesis that, as the number of MDS precursors increases during disease progression they become less succeptible to apoptosis.

Inactivation of tumor suppressor genes, whose products exert an inhibitory influence on cell cycle progression, can lead to neoplastic transformation. In acute myeloid leukemia (AML), the frequency of p53 gene mutations ranges from 4 to 15% in populations from USA and Europe. In an attempt to investigate the frequency of point mutations in the p53 gene in AML Brazilian patients, DNA samples of 35 patients were studied using PCR-SSCP techniques, screening exons 4-10. Mutations were identified in bone marrow DNA in 5 of the 35 AML patients (14.3%), a frequency similar to those reported for Northern American and European populations. The overall survival of patients with mutations in the p53 gene was significantly shorter than for patients without mutations.

The frequency of ras gene mutations varies from 11 to 27% in AML populations from the United States and Europe but it seems that there is no study regarding the frequency of mutated N-ras gene in patients with AML in South America. In order to study the frequency of N-ras gene mutations (exons 1 and 2) in Brazilian patients with AML and to evaluate the possible correlation between the presence of the mutation and clinical features, 40 patients were analyzed. N-ras mutations were identified in DNA samples from eight of 40 AML patients (20%). No significant correlation was found between N-ras mutation and age, sex, race, response to therapy, FAB subtype or occupational exposure. However, the overall survival and AML-free survival were significantly shorter in patients with N-ras mutations than in those without these abnormalities.