Quantitative Detection of Enterotoxigenic Bacteroides fragilis Subtypes Isolated from Children with and without Diarrhea

A rapid real-time PCR ( RT-PCR) approach was developed to detect the bft gene subtypes in Bacteroides fragilis isolated from fecal samples. DNA obtained from diarrhea (110) and nondiarrhea (150) samples was evaluated. Subtype 1 was observed in 9 (8.2%) diarrhea and 7 (4.7%) nondiarrhea samples. Subtype 2 was not detected in any DNA samples, and subtype 3 was observed in only 1 diarrhea sample. The presence of the bft-1 gene did not show any statistically significant differences between the groups of children. This technique could be used to evaluate a possible correlation between disease and the presence of B. fragilis enterotoxin.

Balanoposthitis caused by Pseudomonas aeruginosa co-producing metallo-beta-lactamase and 16S rRNA methylase in children with hematological malignancies

Balanoposthitis is defined as the inflammation of the glans penis and its foreskin. In the presence of other underlying medical conditions, this localized infection may spread systemically, serving as a source of fever and bacteremia in neutropenic males. Two rare cases of balanoposthitis caused by a clonally related Pseudomonas aeruginosa isolate co-producing the SPM-1 metallo-beta-lactamase and the novel 16S rRNA methylase RmtD are described. Four multidrug-resistant (MDR) P. aeruginosa isolates were successively recovered from glans/foreskin swabs and urine cultures from two uncircumcised pediatric patients, one with Burkitt`s non-Hodgkin`s lymphoma and one with acute lymphoblastic leukemia. Clinically, preputial colonization by MDR P. aeruginosa evolved to severe balanoposthitis with glans/foreskin lesions as a source of fever. Combination therapy of ciprofloxacin and/or aztreonam (systemic) plus polymyxin B (topical) was effective once reversion of the neutropenic condition was achieved. Although P. aeruginosa remains an unusual cause of balanoposthitis, these cases should alert the physician to the potential pathogenicity of this bacterium. Furthermore, co-production of metallo-beta-lactamase and 16S rRNA methylase has a potential impact on the empirical management of complicated infections caused by P. aeruginosa. Crown Copyright (C) 2009 Published by Elsevier Ltd on behalf of International Society for Infectious Diseases. All rights reserved.

Permanence of stability for a class of system of differential equations with two delays

The paper studies a class of a system of linear retarded differential difference equations with several parameters. It presents some sufficient conditions under which no stability changes for an equilibrium point occurs. Application of these results is given. (c) 2007 Elsevier Ltd. All rights reserved.

Corpus callosum in maltreated children with posttraumatic stress disorder: A diffusion tensor imaging study

Contrary to expectations derived from preclinical studies of the effects of stress, and imaging studies of adults with posttraumatic stress disorder (PTSD), there is no evidence of hippocampus atrophy in children with PTSD. Multiple pediatric studies have reported reductions in the corpus callosum - the primary white matter tract in the brain. Consequently, in the present study, diffusion tensor imaging was used to assess white matter integrity in the corpus callosum in 17 maltreated children with PTSD and 15 demographically matched normal controls. Children with PTSD had reduced fractional anisotropy in the medial and posterior corpus, a region which contains interhemispheric projections from brain structures involved in circuits that mediate the processing of emotional stimuli and various memory functions - core disturbances associated with a history of trauma. Further exploration of the effects of stress on the corpus callosum and white matter development appears a promising strategy to better understand the pathophysiology of PTSD in children. (C) 2007 Elsevier Ireland Ltd. All rights reserved.