The Denys-Drash syndrome is characterised by a typical nephropathy, genital abnormalities and also predisposes to the development of Wilms' tumor. These patients eventually go into end stage renal failure. A candidate Wilms' tumor gene, WT1, from the 11p13 chromosome region has recently been cloned. We have analysed the DNA sequence in constitutional cells from eight patients and have shown heterozygous mutations in six of them. Four of the mutations were in exon 9, all resulting in missense mutations. Three were at nucleotide position 1180 resulting in an arg > trp amino acid change. The other was at position 1186 converting an asp > asn in the predicted resultant protein. One patient had a missense mutation in exon 8, converting an arg > his. A single base pair insertion at nucleotide position 821 in exon 6 resulted in the generation of a premature stop codon in the last patient. We were unable to find a mutation in one patient despite complete sequencing of the genomic sequence of the gene. The last patient carried a constitutional deletion of the 11p13 region and no additional mutation was found. There was no obvious correlation between the type of mutation and phenotypic expression. These results further demonstrate that the WT1 gene is important in both the development of the kidney and the genito-urinary system.

The high proportion of indeterminate results of the screening test for human T-lymphotropic virus (HTLV) infection has been a challenge worldwide. In this study, 60 persons with seroindeterminate results for HTLV were followed until their serological status was defined. At least two independent serological tests (EIA and WB) from sequential samples were performed at an average interval of 4.4 years, totaling 141 serum samples tested. Seroconversion occurred in 12 individuals (reactive by EIA, positive by WB and PCR), and 48 were classified as false reactions (non-reactive EIA and negative PCR, but indeterminate WB). The seroconverter group had epidemiological features similar to those seen in HTLV-1 carriers, and the average time of follow-up for seroconversion was 4 years. In the group with false reactions, the most frequent indeterminate WB pattern in the samples was the presence of p24 alone. This pattern was absent in the seroconverter group, suggesting that p24 alone is an indicator of false reactivity. In contrast, the presence of p19 and p24 seems to be an indicator of true reactivity, since this pattern was frequent (66.7%) among the seroconverters and much less common (10.4% of the first samples) among the individuals with false reactions (P = 0.0001). Thus, HTLV infection may be suspected when reactivity to p19 and p24 is observed. Individuals with an indeterminate WB pattern should be followed-up and retested. The improvement of the HTLV algorithm screening of blood donors has been necessary to reduce inconclusive results and to avoid unnecessary follow-up to define the status of infection.

BackgroundEscherichia coli is a normal inhabitant of the gut which upon acquiring virulence factors becomes potentially able to cause diseases. Although E. coli population augments in Crohn’s disease (CD), the reason of this proliferation is not yet clear. CD associated E. coli shows features of extraintestinal pathogenic categories (ExPEC), and eventually the ability to invade cultured epithelial cells, a property observed among diarrheagenic E. coli (DEC). In this work, data on the characterization of an E. coli isolate from a CD patient reveal that, besides invasiveness, CD associated E. coli may harbor other typical DEC markers, namely those defining enterohemorragic (EHEC) and enteroaggregative (EAEC) pathotypes.ResultsThe studied strain, detected both in an ileum biopsy and stools, belonged to the B2 E. coli reference collection (EcoR) phylogroup and harbored the intimin, Shiga cytotoxin 1, and AggR transcriptional activator encoding genes (eae, stx1, aggR, respectively); displayed aggregative adherence to Hep-2 cells and an ability to enter Caco-2 cells four times as high as that of EIEC reference strain and half of invasiveness of AIEC LF82. It was able to enter and replicate in J774 macrophages with invasiveness 85 times as high as that of LF82, but with only one sixth of the intracellular proliferation ability of the later. Extracellular products with cytotoxic activity on Vero cells were detected in strain’s cultures. Preliminary analysis indicated similarity of this strain’s genome with that of O104:H4/2011C-3493.MethodsFollowing its isolation from a resected CD patient, the strain was characterized by in vitro adhesion and invasion assays to Hep-2, invasion to Caco-2 cells and to J774 macrophages and tested for the ability to form biofilm and to produce Shiga cytotoxins. PCRs were carried out to identify virulence genetic markers and for EcoR phylogrouping. The strain’s genome was sequenced by means of Ion torrent PGM platform.ConclusionThe detection, in a CD patient, of an E. coli combining virulence features of multiple DEC pathotypes seems not only to stress the relevance of E. coli to CD etiopathogenesis but also to indicate the existence of new and potentially more virulent strains putatively associated with this disease.

Background: Infections with Human Papillomavirus (HPV) are the main cause of cervical cancer. Since 2014, the HPV vaccine was introduced in the Brazilian National Vaccination Calendar. The purpose of this study was to assess the knowledge of adolescent girls and their mothers/guardians about HPV and HPV vaccine, identify the factors associated with this knowledge, and evaluate immunization dropout rate. Methods: This was a cross-sectional study involving adolescent girls and their mothers/guardians. Participants underwent an interview that addressed sociodemographic data, sexual and gynecological history, and knowledge about HPV, HPV vaccine and cervical cancer. The third quartile of the total score was established as a cutoff for assessing knowledge. Adolescents who correctly answered more than four questions and mothers/guardians who obtained more than five correct responses were categorized into high knowledge. Poisson regression analysis was performed to identify variables associated with low knowledge. Vaccination records were used to assess immunization dropout rates. Any adolescent who did not complete the two-dose vaccination schedule was considered dropout. Results: A total of 666 adolescent girls and 623 mothers/guardians were interviewed. Low knowledge was observed in 76.7% of adolescents and 79.8% of mothers/guardians. Most were unaware of the causal relationship between HPV and cervical cancer, signs and symptoms of HPV infection, and had limited knowledge about the HPV vaccine. Factors associated with low knowledge of adolescents were aged 12 years [IRR 1.2 (95% CI 1. 1-1.3)] or less [IRR 1.3 (95% CI (1. 2-1.4)]; household income lower than US$750 [IRR 1.7 (95% CI 1. 1-2.6)] and household income between US$751 and US$1500 [IRR 1.6 (95% CI 1.0-2.6)]. Among mothers/guardians, low knowledge was related to having completed elementary school or less [IRR 1.5 (95% CI 1. 2-2.0)]; and household income lower than US$750 [IRR 1.2 (95% CI 1.0-1.4)]. Knowledge of adolescents and mothers/guardians was not associated with vaccine uptake. HPV immunization dropout rate was considered high (32.3%).