Two-stage tuberculosis diagnostics: combining centrifugal microfluidics to detect TB infection and Inh and Rif resistance at the point of care with subsequent antibiotic resistance profiling by targeted NGS.

Globally, tuberculosis (TB) remains the deadliest bacterial infectious disease, and spreading antibiotic resistances is the biggest challenge for combatting the disease. Rapid and comprehensive diagnostics including drug susceptibility testing (DST) would assure early treatment, reduction of morbidity and the interruption of transmission chains. To date, rapid genetic resistance testing addresses only one to four drug groups while complete DST is done phenotypically and takes several weeks. To overcome these limitations, we developed a two-stage workflow for rapid TB diagnostics including DST from a single sputum sample that can be completed within three days. The first stage is qPCR detection of M. tuberculosis complex (MTBC) including antibiotic resistance testing against the first-line antibiotics, isoniazid (Inh) and rifampicin (Rif). The test is automated by centrifugal microfluidics and designed for point of care (PoC). Furthermore, enriched MTBC DNA is provided in a detachable sample tube to enable the second stage: if the PCR detects MTBC and resistance to either Inh or Rif, the MTBC DNA is shipped to specialized facilities and analyzed by targeted next generation sequencing (tNGS) to assess the complete resistance profile. Proof-of-concept testing of the PoC test revealed an analytical sensitivity of 44.2 CFU ml-1, a diagnostic sensitivity of 96%, and a diagnostic specificity of 100% for MTBC detection. Coupled tNGS successfully provided resistance profiles, demonstrated for samples from 17 patients. To the best of our knowledge, the presented combination of PoC qPCR with tNGS allows for the fastest comprehensive TB diagnostics comprising decentralized pathogen detection with subsequent resistance profiling in a facility specialized in tNGS.

Development and Characterization of a 96-Well Exposure System for Safety Assessment of Nanomaterials.

In this study, a 96-well exposure system for safety assessment of nanomaterials is developed and characterized using an air-liquid interface lung epithelial model. This system is designed for sequential nebulization. Distribution studies verify the reproducible distribution over all 96 wells, with lower insert-to-insert variability compared to non-sequential application. With a first set of chemicals (TritonX), drugs (Bortezomib), and nanomaterials (silver nanoparticles and (non-)fluorescent crystalline nanocellulose), sequential exposure studies are performed with human lung epithelial cells followed by quantification of the deposited mass and of cell viability. The developed exposure system offers for the first time the possibility of exposing an air-liquid interface model in a 96-well format, resulting in high-throughput rates, combined with the feature for sequential dosing. This exposure system allows the possibility of creating dose-response curves resulting in the generation of more reliable cell-based assay data for many types of applications, such as safety analysis. In addition to chemicals and drugs, nanomaterials with spherical shapes, but also morphologically more complex nanostructures can be exposed sequentially with high efficiency. This allows new perspectives on in vivo-like and animal-free approaches for chemical and pharmaceutical safety assessment, in line with the 3R principle of replacing and reducing animal experiments.

A New Type of Valence Tautomerism in Cobalt Dioxolene Complexes - Temperature-Induced Transition from a Cobalt(III) Catecholate to a Low-Spin Cobalt(II) Semiquinonate State.

The synthesis and characterization of the monocationic cobalt(III) catecholate complex [Co(L-N4 t Bu2 )(Cl2 cat)]+ (L-N4 t Bu2 =N,N'-Di-tert.-butyl-2,11-diaza[3.3](2,6)pyridinophane, Cl2 cat2- =4,5-dichlorocatecholate) are presented. The complex exhibits valence tautomeric properties in solution; but, in contrast to the usually observed conversion from a cobalt(III) catecholate to a high-spin cobalt(II) semiquinonate state, valence tautomerism of [Co(L-N4 t Bu2 )(Cl2 cat)]+ leads to the formation of a low-spin cobalt(II) semiquinonate complex upon raising the temperature. This new type of valence tautomerism for a cobalt dioxolene complex has been unambiguously established by a detailed spectroscopic investigation using variable-temperature NMR, IR and UV-Vis-NIR spectroscopy. Determination of the enthalpies and entropies characterizing the valence tautomeric equilibria in various solutions shows that the influence of the solvent is almost exclusively entropic.

Fluorescence Labeling of Cellulose Nanocrystals-A Facile and Green Synthesis Route.

Efficient chemical modification of cellulose nanocrystals (CNCs) by grafting commonly involves aprotic solvents, toxic reactants, harsh reaction conditions, or catalysts, which have negative effects on the particle character, reduced dispersibility and requires further purification, if products are intended for biomedical applications. This work, in contrast, presents a robust, facile, and green synthesis protocol for the grafting of an amino-reactive fluorophore like fluorescein isothiocyanate (FITC) on aqueous CNCs, combining and modifying existent approaches in a two-step procedure. Comparably high grafting yields were achieved, which were confirmed by thermogravimetry, FTIR, and photometry. The dispersive properties were confirmed by DLS, AF4-MALS, and TEM studies. The presented route is highly suitable for the introduction of silane-bound organic groups and offers a versatile platform for further modification routes of cellulose-based substrates.

[Impaired recognition of environmental sounds in patients with dementia : I can hear but I do not understand]. / Störung des Erkennens von Umweltgeräuschen bei Demenz : Ich höre aber ich verstehe nicht.

BACKGROUND: Impairment of central auditory processing is a well-known symptom of neurodegenerative dementia; however, whilst numerous studies have examined verbal processing impairment, to date few have attempted to describe impairments of non-verbal, environmental sound recognition in patients with dementia. As these impairments may have direct implications on patient support and care, such studies are urgently necessary. AIM OF THE STUDY: The aim of the study was to determine whether the recognition of meaningful environmental sounds is impaired in patients with mild or early stage neurodegenerative dementia. PATIENTS AND METHODS: We developed a test of non-verbal sound recognition consisting of 16 sound sequences from the familiar and unfamiliar environments. We included 18 patients with mild cognitive impairment and mild dementia caused by Alzheimer's disease and frontotemporal dementia, as well as 20 cognitively healthy controls. RESULTS: Patients and controls were given the test of recognizing 16 meaningful sounds from the familiar and unfamiliar environments. Patients with dementia performed significantly worse in comparison to cognitively healthy controls. Whilst healthy controls correctly recognized on average 12.1 ± 2.2 out of 16 sounds, cognitively impaired patients recognized 9.2 ± 2.5. Correlation analysis showed that the mini mental state examination (MMSE) scores were positively correlated with the number of correctly recognized sounds (MMSE: r = 0.556, p = 0.017). DISCUSSION: The fact that even in mild stages of Alzheimer's disease or frontotemporal dementia patients either do not recognize or misinterpret environmental sounds must be taken into consideration not only in everyday life but in particular when patients need to leave their familiar living environment, whether temporarily (e. g. hospitalization) or permanently (e. g. nursing home admission).

Molecular characterization of an Enterovirus 71 causing neurological disease in Germany.

Enterovirus 71 (EV71) is mainly known as a cause of hand-foot-and-mouth disease (HFMD) but sometimes associated with neurological disease, even as fatal brainstem encephalitis. In Europe, EV71 infections are extremely rare, in contrast to the worldwide situation. This is the first report of molecular characterization of an EV71 strain isolated in Europe that had caused neurological disease. The german strain is closest related to sublineage B2 strains isolated in the United States, which where mainly associated with neurological disease. Phylogenetic analysis also showed that the strain must have been imported to Germany several years ago, and continues to circulate since then.