Identification of type II toxin-antitoxin modules in Burkholderia pseudomallei

© 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reservedThis is an open access article that is freely available in ORE or from the publisher's web site. Please cite the published version.Type II toxin-antitoxin (TA) systems are believed to be widely distributed amongst bacteria although their biological functions are not clear. We have identified eight candidate TA systems in the genome of the human pathogen Burkholderia pseudomallei. Five of these were located in genome islands. Of the candidate toxins, BPSL0175 (RelE1) or BPSS1060 (RelE2) caused growth to cease when expressed in Escherichia coli, whereas expression of BPSS0390 (HicA) or BPSS1584 (HipA) (in an E. coli ΔhipBA background) caused a reduction in the number of culturable bacteria. The cognate antitoxins could restore growth and culturability of cells.Wellcome Trus

Feasibility, usability and clinical value of intensive longitudinal diary assessments in older persons with cognitive impairment and depressive symptoms

OBJECTIVES: To evaluate the feasibility, usability and clinical value of daily diary assessments combined with actigraphy in older persons with cognitive impairment.METHODS: For 63 days, patients ≥60 years with cognitive impairments filled out a daily diary (including standardized questionnaires and cognitive test battery), and wore an actiwatch (sleep). After the study, participants and clinicians received personal feedback about patterns and daily triggers of depressive symptoms, sleep and cognitive performance. We assessed feasibility (participation rate, compliance and subjective burden), usability (variability and floor- or ceiling effects) and clinical value for patients and their clinicians (questionnaires).RESULTS: Of 96 eligible patients, 13 agreed to participate (13.5%). One patient dropped out after 2 days, another after 37 days, and another did not complete the cognitive test battery. Compliance rate was high (6.7-10% missing values). Subjective burden was relatively low. Time-series data showed sufficient variability and no floor- or ceiling effects, except for one relevant ceiling effect on the One Back task. The personal feedback report was considered insightful by 4 out of 11 participants and 5 out of 7 clinicians.CONCLUSION: Daily assessments are suitable for a minority of cognitively impaired older persons, but is helpful to increase insight into their symptoms.</p

Techno‐economic assessment and comparison of different plastic recycling pathways: A German case study

Greenhouse gas (GHG) emissions need to be reduced to limit global warming. Plastic production requires carbon raw materials and energy that are associated today with predominantly fossil raw materials and fossil GHG emissions. Worldwide, the plastic demand is increasing annually by 4%. Recycling technologies can help save or reduce GHG emissions, but they require comparative assessment. Thus, we assess mechanical recycling, chemical recycling by means of pyrolysis and a consecutive, complementary combination of both concerning Global Warming Potential (GWP) [CO2e], Cumulative Energy Demand (CED) [MJ/kg], carbon efficiency [%], and product costs [€] in a process‐oriented approach and within defined system boundaries. The developed techno‐economic and environmental assessment approach is demonstrated in a case study on recycling of separately collected mixed lightweight packaging (LWP) waste in Germany. In the recycling paths, the bulk materials polypropylene (PP), polyethylene (PE), polyvinylchloride (PVC), and polystyrene (PS) are assessed. The combined mechanical and chemical recycling (pyrolysis) of LWP waste shows considerable saving potentials in GWP (0.48 kg CO2e/kg input), CED (13.32 MJ/kg input), and cost (0.14 €/kg input) and a 16% higher carbon efficiency compared to the baseline scenario with state‐of‐the‐art mechanical recycling in Germany. This leads to a combined recycling potential between 2.5 and 2.8 million metric tons/year that could keep between 0.8 and 2 million metric tons/year additionally in the (circular) economy instead of incinerating them. This would be sufficient to reach both EU and German recycling rate targets (EC 2018). This article met the requirements for a gold‐silver JIE data openness badge described at http://jie.click/badges

Spin and interaction effects on charge distribution and currents in one-dimensional conductors and rings within the Hartree-Fock approximation

Using the self--consistent Hartree-Fock approximation for electrons with spin at zero temperature, we study the effect of the electronic interactions on the charge distribution in a one-dimensional continuous ring containing a single $\delta$ scatterer. We reestablish that the interaction suppresses the decay of the Friedel oscillations. Based on this result, we show that in an infinite one dimensional conductor containing a weak scatterer, the current is totally suppressed because of a gap opened at the Fermi energy. In a canonical ensemble of continuous rings containing many scatterers, the interactions enhance the average and the typical persistent current.Comment: 5 pages, 4 figure

A Stakeholder-Based Assessment Model (SAM) for Resource -Efficiency Measures in the Construction Industry

In recent decades, the shortage of natural resources like primary raw materials has increasingly shifted into the focus of public discussion and research. Especially in the resource-intensive construction sector the implementation of a circular economy can strongly contribute to a reduction of primary resource demand. Positive developments can be noticed already, but the desired goal of an effective circular economy is still not being reached. For instance, the usage of recycled raw materials as substitutes for primary resources could be significantly higher. In order to implement the protection of resources in the construction sector, it is essential to assess resource-saving measures and their impact on conservations as well as stakeholders motivation to implement them. For this purpose, a Stakeholder-based Assessment Model (SAM) is introduced to provide recommendations for political actions and potent measures to foster the circular economy in the construction sector that lead to increased reuse and recycling of construction materials. In the SAM, relevant actors are identified and their characteristics and preferences as well as the level of influence on each other are modelled and validated for Germany. Moreover, available resource-conserving measures concerning the construction sector are identified and related measures are grouped together. Thereupon the influence of measures on stakeholders and their willingness to take positive actions in terms of a circular economy have been investigated and modelled. Relevant model data has been gathered by intensive literature review, surveys and expert interviews. The results show that measures regarding lifecycle oriented planning of buildings as well as the development of stakeholder cooperation are the most effective ones to save resources and to reduce the disposal of construction material. Furthermore the results demonstrate that a leading role of public authorities is crucial to foster a circular economy

Exact calculation of the skyrmion lifetime in a ferromagnetic Bose condensate

The tunneling rate of a skyrmion in ferromagnetic spin-1/2 Bose condensates through an off-centered potential barrier is calculated exactly with the periodic instanton method. The prefactor is shown to depend on the chemical potential of the core atoms, at which level the atom tunnels. Our results can be readily extended to estimate the lifetime of other topological excitations in the condensate, such as vortices and monopoles.Comment: 16 pages, 4 figures, to appear Phys. Rev.

Rapid initial decline in BCR-ABL1 is associated with superior responses to second-line nilotinib in patients with chronic-phase chronic myeloid leukemia

BACKGROUND: We evaluated BCR-ABL1 kinetics in patients treated with nilotinib and analyzed whether a dynamic model of changes in BCR-ABL1 levels over time could be used to predict long-term responses. METHODS: Patients from the nilotinib registration trial (CAMN107A2101; registered at http://www.clinicaltrials.gov as NCT00109707) who had imatinib-resistant or -intolerant Philadelphia chromosome–positive (Ph+) chronic myeloid leukemia (CML) in chronic phase (CP) or accelerated phase with BCR-ABL1 > 10% (on the international scale [IS]) at baseline and, in the first 6 months, had at least three BCR-ABL1 transcript measurements and an average daily dose of at least 720 mg were included in this analysis (N = 123). RESULTS: More than half of patients (65/123; 53%) had a slow monophasic response and the remainder (58/123; 47%) had a biphasic response, in which patients had a rapid initial decrease in BCR-ABL1 transcripts followed by a more gradual response. The biphasic response type strongly correlated with improved event-free survival (EFS). Data in the first 6 months of follow-up were sufficient to predict EFS at 24 months. CONCLUSIONS: Unlike newly diagnosed patients with Ph+ CML-CP—in whom the majority had a biphasic response—approximately half of patients with imatinib-resistant or -intolerant CML had a slower, monophasic response. Second-line patients who did have a biphasic response had an EFS outlook similar to that of newly diagnosed patients treated with imatinib. Our model was comparable to using BCR-ABL1 (IS) ≤ 10% at 6 months as a threshold for predicting EFS

Structural variation, dynamics, and catalytic application of palladium(II) complexes of di-N-heterocyclic carbene-amine ligands

A series of palladium(II) complexes incorporating di-NHC-amine ligands has been prepared and their structural, dynamic and catalytic behaviour investigated. The complexes [trans-(k(2)-(CN)-C-tBu(Bn)CN(Bn)C-tBu)PdCl2] (12) and [trans-(kappa(2)-(CN)-C-Mes(H)C-Mes)PdCl2] (13) do not exhibit interaction between the amine nitrogen and palladium atom respectively. NMR spectroscopy between - 40 and 25 degrees C shows that the di-NHC-amine ligand is flexible expressing C-s symmetry and for 13 rotation of the mesityl groups is prevented. In the related C-1 complex [(kappa(3)-(CN)-C-tBu(H)C-tBu)PdCl][CI] (14) coordination of NHC moieties and amine nitrogen atom is observed between -40 and 25 degrees C. Reaction between 12 - 14 and two equivalents of AgBF4 in acetonitrile gives the analogous complexes [trans-(kappa(2)-(CN)-C-tBu(Bn)C-tBu)PdCl2] (12) and [trans-(kappa(CN)-C-2Mes(H)C-Mes)PdCl2] (13) do not exhibit interaction between the amine nitrogen and palladium atom respectively. NMR spectroscopy between -40 ans 25 degrees C shows the di-NHC-amine ligand is flexible expressing C-s symmetry and for 13 rotation of the mesityl groups is prevented. In the related C-1 complex [kappa(3)-(CN)-C-tBu(H)C-tBu)PdCI][CI] (14) coordination of NHC moieties and amine nitrogen atom is observed between -40 and 25 degrees C.Reaction between 12-14 and two equivalents of AgBF4 in acetonitrile gives the analogous complexes [trans-(kappa(2)-(CN)-C-tBu(H)(CPd)-Pd-tBu(MeCN)(2)][BF4](2) (15), [trans-(kappa(CN)-C-2Mes(H)C-Mes)Pd(MeCN)(2)[BF4](2 (16)) and [(kappa(3)-(CN)-C-tBu(H)C-tBu)Pd(MeCN)][BF4](2) (17) indicating that ligand structure determines amine coordination. The single crystal X-ray structures of 12, 17 and two ligand imidazolium salt precursors C-tBu(H)N(Bn)C(H) (tBu)][CI](2) (2) and [C-tBu(H) N(H)C(H)(tBu)][BPh4](2) (4) have been determined. Complexes 12-14 and 15-17 have been shown to be active precatalysts for Heck and hydroamination reactions respectively

Genomic analysis reveals key aspects of prokaryotic symbiosis in the phototrophic consortium "<em>Chlorochromatium aggregatum</em>"

BACKGROUND: ‘Chlorochromatium aggregatum’ is a phototrophic consortium, a symbiosis that may represent the highest degree of mutual interdependence between two unrelated bacteria not associated with a eukaryotic host. ‘Chlorochromatium aggregatum’ is a motile, barrel-shaped aggregate formed from a single cell of ‘Candidatus Symbiobacter mobilis”, a polarly flagellated, non-pigmented, heterotrophic bacterium, which is surrounded by approximately 15 epibiont cells of Chlorobium chlorochromatii, a non-motile photolithoautotrophic green sulfur bacterium. RESULTS: We analyzed the complete genome sequences of both organisms to understand the basis for this symbiosis. Chl. chlorochromatii has acquired relatively few symbiosis-specific genes; most acquired genes are predicted to modify the cell wall or function in cell-cell adhesion. In striking contrast, ‘Ca. S. mobilis’ appears to have undergone massive gene loss, is probably no longer capable of independent growth, and thus may only reproduce when consortia divide. A detailed model for the energetic and metabolic bases of the dependency of ‘Ca. S. mobilis’ on Chl. chlorochromatii is described. CONCLUSIONS: Genomic analyses suggest that three types of interactions lead to a highly sophisticated relationship between these two organisms. Firstly, extensive metabolic exchange, involving carbon, nitrogen, and sulfur sources as well as vitamins, occurs from the epibiont to the central bacterium. Secondly, ‘Ca. S. mobilis’ can sense and move towards light and sulfide, resources that only directly benefit the epibiont. Thirdly, electron cycling mechanisms, particularly those mediated by quinones and potentially involving shared protonmotive force, could provide an important basis for energy exchange in this and other symbiotic relationships