Targeted exhaled breath analysis for detection of Pseudomonas aeruginosa in cystic fibrosis patients

Background: Pseudomonas aeruginosa (PA) is an important respiratory pathogen for cystic fibrosis (CF) patients. Routine microbiology surveillance is time-consuming, and is best performed on expectorated sputum. As alternative, volatile organic compounds (VOCs) may be indicative of PA colonisation. In this study, we aimed to identify VOCs associated with PA in literature and perform targeted exhaled breath analysis to recognize PA positive CF patients non-invasively. Methods: This study consisted of 1) a literature review to select VOCs of interest, and 2) a cross-sectional CF study. Definitions used: A) PA positive, PA culture at visit/chronically; B) PA free, no PA culture in ≥12 months. Exhaled VOCs were identified via quadrupole MS. The primary endpoint was the area under the receiver operating characteristics curve (AUROCC) of individual VOCs as well as combined VOCs against PA culture. Results: 241 VOCs were identified in literature, of which 56 were further evaluated, and 13 could be detected in exhaled breath in our cohort. Exhaled breath of 25 pediatric and 28 adult CF patients, PA positive (n=16) and free (n=28) was available. 3/13 VOCs were significantly (p<0.05) different between PA groups in children; none were in adults. Notably, a composite model based on 5 or 1 VOC(s) showed an AUROCC of 0.86 (CI 0.71–1.0) and 0.87 (CI 0.72–1.0) for adults and children, respectively. Conclusions: Targeted VOC analysis appears to discriminate children and adults with and without PA positive cultures with clinically acceptable sensitivity values

Targeted exhaled breath analysis for detection of Pseudomonas aeruginosa in cystic fibrosis patients

Background Pseudomonas aeruginosa (PA) is an important respiratory pathogen for cystic fibrosis (CF) patients. Routine microbiology surveillance is time-consuming, and is best performed on expectorated sputum. As alternative, volatile organic compounds (VOCs) may be indicative of PA colonisation. In this study, we aimed to identify VOCs associated with PA in literature and perform targeted exhaled breath analysis to recognize PA positive CF patients non-invasively. Methods This study consisted of 1) a literature review to select VOCs of interest, and 2) a cross-sectional CF study. Definitions used: A) PA positive, PA culture at visit/chronically; B) PA free, no PA culture in ≥12 months. Exhaled VOCs were identified via quadrupole MS. The primary endpoint was the area under the receiver operating characteristics curve (AUROCC) of individual VOCs as well as combined VOCs against PA culture. Results 241 VOCs were identified in literature, of which 56 were further evaluated, and 13 could be detected in exhaled breath in our cohort. Exhaled breath of 25 pediatric and 28 adult CF patients, PA positive (n=16) and free (n=28) was available. 3/13 VOCs were significantly (p<0.05) different between PA groups in children; none were in adults. Notably, a composite model based on 5 or 1 VOC(s) showed an AUROCC of 0.86 (CI 0.71–1.0) and 0.87 (CI 0.72–1.0) for adults and children, respectively. Conclusions Targeted VOC analysis appears to discriminate children and adults with and without PA positive cultures with clinically acceptable sensitivity values

Composition of the Lecointea clade (Leguminosae, Papilionoideae, Swartzieae), a re-evaluation based on combined evidence from morphology and molecular data

We investigated morphological and DNA sequence data for studying the composition and phylogenetic relationships of the Lecointea clade sensu Herendeen and for testing its monophyly. Twenty nine representing 14 genera were analyzed, including all members of the Lecointea clade and some species of the genera Acosmium, Luetzelburgia, Sweetia, Vatairea and Pataireopsis. Ateleia herbert-srnithii, Bocoa mollis, and Myrocarpus frondosus were included as outgroup. Matrices were analyzed using maximum parsimony. Analyses of morphological data, chloroplast DNA trnL sequence data, and combined datasets resulted in similar tree topologies. The Lecointea clade sensu Herendeen, with the additional inclusion of Uribea, is monophyletic in all analyses. Exostyles and Harleyodendron belong to the Lecointea clade and not to the Vatairea clade as recently proposed by Pennington al.5341007101

Effect of Milk and Soy-based Infant Formulas on In Situ Demineralization of Human Primary Enamel

Purpose: The effect of infant formulas sweetened or not with sucrose on primary enamel demineralization and dental biofilm is not known. This study's purpose was to evaluate the effect of infant formula and sucrose association on demineralization of primary enamel and dental biofilm formed. Methods: A cross-over, split-mouth, and blind in situ study was conducted during 3 phases, each of 10 days duration, during which 11 volunteers wore palatal appliances containing slobs of human primary enamel. The dental slabs were extraorally subjected 8 times a day to 6 groups of treatment: distilled and deionized water; 10% sucrose solution; and milk-based and soy-based formula with or without 10% sucrose added. After each phase, the acidogenicity, biochemical and microbiological composition of dental biofilm formed was analyzed, and enamel demineralization was assessed by microhardness. Results: Both formulas induced significant enamel mineral loss, which increased when sucrose was added. Both formulas were fermented, resulting in a decrease of biofilm pH, irrespective of sucrose addition. Also, lactobacilli counts were higher in biofilm formed in the presence of both formulas when compared to the water group. Conclusions: Milk and soy-based formulas present potential to induce demineralization in primary enamel, which increased when sweetened with sucrose. (Pediatr Dent 2010;32:35-40) Received August 20, 2008 I Last Revision January 22, 2009 I Revision Accepted January 25, 2009321354