17 research outputs found
Sensing and inactivation of Bacillus anthracis Sterne by polymer–bromine complexes
We report on the performance of brominated poly(N-vinylpyrrolidone) (PVP-Br), brominated poly(ethylene glycol) (PEG-Br), and brominated poly(allylamine-co-4-aminopyridine) (PAAm-APy-Br) for their ability to decontaminate Bacillus anthracis Sterne spores in solution while also allowing for the sensing of the spores. The polymers were brominated by bromine using carbon tetrachloride or potassium tribromide as solvents, with bromine loadings ranging from 1.6 to 4.2Â mEq/g of polymer. B. anthracis Sterne spores were exposed to increasing concentrations of brominated polymers for 5Â min, while the kinetics of the sporicidal activity was assessed. All brominated polymers demonstrated spore log-kills of 8 within 5Â min of exposure at 12Â mg/mL aqueous polymer concentration. Sensing of spores was accomplished by measuring the release of dipicolinic acid (DPA) from the spore using time-resolved fluorescence. Parent, non-brominated polymers did not cause any release of DPA and the spores remained viable. In contrast, spores exposed to the brominated polymers were inactivated and the release of DPA was observed within minutes of exposure. Also, this release of DPA continued for a long time after spore inactivation as in a controlled release process. The DPA release was more pronounced for spores exposed to brominated PVP and brominated PEG-8000 compared to brominated PAAm-APy and brominated PEG-400. Using time-resolved fluorescence, we detected as low as 2500 B. anthracis spores, with PEG-8000 being more sensitive to low spore numbers. Our results suggest that the brominated polymers may be used effectively as decontamination agents against bacterial spores while also providing the sensing capability.Defense Threat Reduction Agency (DTRA
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Neurophysiological differences between patients clinically at high risk for schizophrenia and neurotypical controls – first steps in development of a biomarker
Background: Schizophrenia is a severe, disabling and prevalent mental disorder without cure and with a variable, incomplete pharmacotherapeutic response. Prior to onset in adolescence or young adulthood a prodromal period of abnormal symptoms lasting weeks to years has been identified and operationalized as clinically high risk (CHR) for schizophrenia. However, only a minority of subjects prospectively identified with CHR convert to schizophrenia, thereby limiting enthusiasm for early intervention(s). This study utilized objective resting electroencephalogram (EEG) quantification to determine whether CHR constitutes a cohesive entity and an evoked potential to assess CHR cortical auditory processing. Methods: This study constitutes an EEG-based quantitative neurophysiological comparison between two unmedicated subject groups: 35 neurotypical controls (CON) and 22 CHR patients. After artifact management, principal component analysis (PCA) identified EEG spectral and spectral coherence factors described by associated loading patterns. Discriminant function analysis (DFA) determined factors’ discrimination success between subjects in the CON and CHR groups. Loading patterns on DFA-selected factors described CHR-specific spectral and coherence differences when compared to controls. The frequency modulated auditory evoked response (FMAER) explored functional CON–CHR differences within the superior temporal gyri. Results: Variable reduction by PCA identified 40 coherence-based factors explaining 77.8 % of the total variance and 40 spectral factors explaining 95.9 % of the variance. DFA demonstrated significant CON–CHR group difference (P <0.00001) and successful jackknifed subject classification (CON, 85.7 %; CHR, 86.4 % correct). The population distribution plotted along the canonical discriminant variable was clearly bimodal. Coherence factors delineated loading patterns of altered connectivity primarily involving the bilateral posterior temporal electrodes. However, FMAER analysis showed no CON–CHR group differences. Conclusions: CHR subjects form a cohesive group, significantly separable from CON subjects by EEG-derived indices. Symptoms of CHR may relate to altered connectivity with the posterior temporal regions but not to primary auditory processing abnormalities within these regions
Young children with psychotic symptoms and risk for suicidal thoughts and behaviors: a research note
Abstract Objective Suicidal thoughts and behaviors (STBs) are prevalent among youth with psychotic disorders (PD) relative to the general population. Recent research now suggests that STBs may present during the prodromal phase of the disease, or the clinical high risk (CHR) state. While this knowledge is important for the development of suicide prevention strategies in adolescent and adult populations, it remains unclear whether risk for suicide extends to children with or at risk for psychosis. The current study is an extension of previous work assessing STBs in youth across the psychosis continuum. We examine STBs in 37 CHR and PD children ages 7–13 years old, and further explore the prodromal symptom correlates of STB severity among CHR children. Results CHR and PD children endorsed STBs with a frequency and severity similar to what is observed in older CHR and PD populations. A number of children had never previously vocalized their suicidal plans or intent. Among CHR children, Social Anhedonia and Odd Behavior or Appearance were significantly correlated with STB severity. These findings underscore the importance of screening for STBs even in young children presenting with psychotic symptoms
De novo variant of TRRAP in a patient with very early onset psychosis in the context of non-verbal learning disability and obsessive-compulsive disorder: a case report
Abstract Background TRRAP encodes a multidomain protein kinase that works as a genetic cofactor to influence DNA methylation patterns, DNA damage repair, and chromatin remodeling. TRRAP protein is vital to early neural developmental processes, and variants in this gene have been associated with schizophrenia and childhood disintegrative disorder. Case presentation Here, we report on a patient with a de novo nonsynonymous TRRAP single-nucleotide variant (EST00000355540.3:c.5957G > A, p.Arg1986Gln) and early onset major depression accompanied by a psychotic episode (before age 10) that occurred in the context of longer standing nonverbal learning disability and a past history of obsessions and compulsions. Conclusions The de novo variant and presentation of very early onset psychosis indicate a rare Mendelian disorder inheritance model. The genotype and behavioral abnormalities of this patient are reviewed