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Longitudinal studies regarding the reproducibility of Interferon-gamma release assay (IGRA) T-SPOT.TB for the diagnosis of Mycobacterium tuberculosis (M. tb) infection in serial testing are limited. We retrospectively analysed results of serially tested subjects in a medical laboratory in Germany over a time period of 14 years. From October 2004 to December 2018, a total of 5440 subjects were identified with a second T-SPOT.TB test after a median time interval of 258 days (interquartile range [IQR] 62-665). Consistently negative (n = 4520) or positive results (n = 682) were observed in 5202 (95.6%) subjects, indicating a high degree of concordance in serial testing (κ = 0.83). Test conversions occurred in 101 of 4621 (2.2%) subjects with initially negative tests. Of 819 subjects with initially positive test results, 137 (16.7%) had a test reversion which was associated with low spot numbers of the first test. Of 529 subjects retested within 1 year, only 60 (11.3%) displayed a test reversion. In subjects retested after more than 1 year, 77 of 290 (26.6%) tests reverted. This significantly higher rate of test reversions after more than 1 year was age-dependent and only observed in subjects above the age of 40 years. In the medical laboratory, the T-SPOT.TB test demonstrates a high reproducibility in serial testing.

Increasing antimicrobial resistance compels the search for next-generation inhibitors with differing or multiple molecular targets. In this regard, energy conservation in Mycobacterium tuberculosis has been clinically validated as a promising new drug target for combatting drug-resistant strains of M. tuberculosis. Here, we show that HM2-16F, a 6-substituted derivative of the FDA-approved drug amiloride, is an anti-tubercular inhibitor with bactericidal properties comparable to the FDA-approved drug bedaquiline (BDQ; Sirturo®) and inhibits the growth of bedaquiline-resistant mutants. We show that HM2-16F weakly inhibits the F1Fo-ATP synthase, depletes ATP, and affects the entry of acetyl-CoA into the Krebs cycle. HM2-16F synergizes with the cytochrome bcc-aa3 oxidase inhibitor Q203 (Telacebec) and co-administration with Q203 sterilizes in vitro cultures in 14 days. Synergy with Q203 occurs via direct inhibition of the cytochrome bd oxidase by HM2-16F. This study shows that amiloride derivatives represent a promising discovery platform for targeting energy generation in drug-resistant tuberculosis.

The following paper describes an approach to process modeling and simulation of the gas phase in an electric arc furnace (EAF). The work presented represents the continuation of research by Logar, Dovžan, and Skrjanc on modeling the heat and mass transfer and the thermochemistry in an EAF. Due to the lack of off-gas measurements, Logar et al. modeled a simplified gas phase under consideration of five gas components and simplified chemical reactions. The off-gas is one of the main continuously measurable EAF process values and the off-gas flow represents a heat loss up to 30 pct of the entire EAF energy input. Therefore, gas phase modeling offers further development opportunities for future EAF optimization. This paper presents the enhancement of the previous EAF gas phase modeling by the consideration of additional gas components and a more detailed heat and mass transfer modeling. In order to avoid the increase of simulation time due to more complex modeling, the EAF model has been newly implemented to use an efficient numerical solver for ordinary differential equations. Compared to the original model, the chemical components H2, H2O, and CH4 are included in the gas phase and equilibrium reactions are implemented. The results show high levels of similarity between the measured operational data from an industrial scale EAF and the theoretical data from the simulation within a reasonable simulation time. In the future, the dynamic EAF model will be applicable for on- and offline optimizations, e.g., to analyze alternative input materials and mode of operations.

Nucleolar channel systems (NCSs), micron-sized organelles specific to nuclei of human endometrial epithelial cells (EECs), are robust markers of the midluteal phase under the apparent control of progesterone. To gain further insight into the role of progesterone in NCS formation, we quantitatively assessed their sensitivity to oral contraceptive pills (OCPs) using immunofluorescence-based detection of NCSs. Comparison of endometrial biopsies and serum progesterone levels on cycle day (CD) 10 and 20 (LH +6/7) of 6 naturally cycling women and 6 OCP users demonstrated that OCPs interfered with NCS formation on CD20, their natural peak presence. Although this confirmed prior observation based on electron microscopic sampling, OCPs unexpectedly induced limited but distinct amounts of NCSs already on CD10, when they are never present in natural cycles. Thus, OCPs can cause secretory changes in the endometrium during the proliferative phase. In a novel finding, robust NCS formation on CD20 was dependent on a 4 ng/mL progesterone threshold but did not correlate linearly with serum progesterone levels. Given the threshold being close to that serving as evidence for ovulation, NCSs can serve as ovulation markers.

The aim of this study was to investigate the efficacy of idebenone on neurological function as assessed by ICARS and FARS neurological rating scales in pediatric Friedreich's ataxia (FRDA) patients. Sixty-eight pediatric patients were enrolled in an open-label extension study (IONIA-E) where patients received idebenone (Catena(®), 150 mg film-coated tablets) at a weight-adjusted dose of 1,350/2,250 mg/day for 12 months after patients had completed a double-blind, randomized, placebo-controlled study (IONIA) receiving either idebenone at a weight-adjusted dose of 450/900 or 1,350/2,250 mg/day or placebo for 6 months. Changes in ICARS and FARS total scores and subscores were recorded for the 12-month IONIA-E study and for the 18-month combined IONIA and IONIA-E study period. Data analyzed by a mixed-model repeated-measures ANCOVA relative to baseline resulted in least square means for the change in ICARS for the IONIA-E study of +0.98 points (SEM 0.73; p = 0.180), indicating a trend for worsening. However, combined with the IONIA study the change was -1.03 ± 0.68 points (p = 0.132), indicating a trend for improvement in neurological function over the 18-month period. Importantly, patients who received idebenone 1,350/2,250 mg/day over this period significantly improved in neurological function (change in ICARS: -3.02 ± 1.22, p = 0.014). The improvement in neurological function over time was best seen when the posture and stance subscore was excluded from the analysis. Comparable data were obtained with the FARS. The findings of the open-label IONIA-E study combined with the double-blind IONIA study indicate that idebenone at a dose of 1,350/2,250 mg/day may offer a therapeutic benefit to pediatric FRDA patients by stabilizing the overall neurological function and improving fine motor skills and speech.

Based on the spherical cavity expansion (SCE) problem, Cudmani and Osinov (Can Geotech J 38:622–638, 2001), Osinov and Cudmani (Int J Numer Anal Method Geomech 25:473–495, 2001) developed a semi-empirical method of interpretation of CPT for coarse-grained soils (sand, gravel) using a hypoplastic constitutive model. Using a material-independent shape factor, the cone penetration resistance was related to the limit pressure required to expand a spherical cavity. The shape factor was observed to be a function of the soil state only, in particular the pressure-dependent relative density. This paper presents an analogous interpretation technique for CPT in fine-grained soils using the shape factor concept, Cavity Expansion approach, and a hypoplastic constitutive model. Relations for the shape factor and the limit pressure have been proposed based on the parameters affecting these quantities. A validation of the proposed interpretation technique with experimental results has also been performed.

Continental lithosphere can undergo pervasive internal deformation, often distributed over broad zones near plate boundaries. However, because of the paucity of observational constraints on three-dimensional movement at depth, patterns of flow within the lithosphere remain uncertain. Endmember models for lithospheric flow invoke deformation localized on faults or deep shear zones or, alternatively, diffuse, viscous-fluid-like flow. Here we determine seismic Rayleigh-wave anisotropy in the crust and mantle of the Aegean region, an archetypal example of continental deformation. Our data reveal a complex, depth-dependent flow pattern within the extending lithosphere. Beneath the northern Aegean Sea, fast shear wave propagation is in a North-South direction within the mantle lithosphere, parallel to the extensional component of the current strain rate field. In the south-central Aegean, where deformation is weak at present, anisotropic fabric in the lower crust runs parallel to the direction of palaeo-extension in the Miocene. The close match of orientations of regional-scale anisotropic fabric and the directions of extension during the last significant episodes of deformation implies that at least a large part of the extension in the Aegean has been taken up by distributed viscous flow in the lower crust and lithospheric mantle.

The microscopic mechanism of coupled c-ring rotation and ion translocation in F(1)F(o)-ATP synthases is unknown. Here we present conclusive evidence supporting the notion that the ability of c-rings to rotate within the F(o) complex derives from the interplay between the ion-binding sites and their nonhomogenous microenvironment. This evidence rests on three atomic structures of the c(15) rotor from crystals grown at low pH, soaked at high pH and, after N,N'-dicyclohexylcarbodiimide (DCCD) modification, resolved at 1.8, 3.0 and 2.2 Å, respectively. Alongside a quantitative DCCD-labeling assay and free-energy molecular dynamics calculations, these data demonstrate how the thermodynamic stability of the so-called proton-locked state is maximized by the lipid membrane. By contrast, a hydrophilic environment at the a-subunit-c-ring interface appears to unlock the binding-site conformation and promotes proton exchange with the surrounding solution. Rotation thus occurs as c-subunits stochastically alternate between these environments, directionally biased by the electrochemical transmembrane gradient.

Over the last 25 years mining-induced seismicity in the Ruhr area has continuously been monitored by the Ruhr-University Bochum. About 1,000 seismic events with local magnitudes between 0.7 ≤ ML ≤ 3.3 are located every year. For example, 1,336 events were located in 2006. General characteristics of induced seismicity in the entire Ruhr area are spatial and temporal correlation with mining activity and a nearly constant energy release per unit time. This suggests that induced stresses are released rapidly by many small events. The magnitude–frequency distribution follows a Gutenberg–Richter relation which is a result from combining distributions of single longwalls that themselves show large variability. A high b-value of about 2 was found indicating a lack of large magnitude events. Local analyses of single longwalls indicate that various factors such as local geology and mine layout lead to significant differences in seismicity. Stress redistribution acts very locally since differences on a small scale of some hundreds of meters are observed. A regional relation between seismic moment M0 and local magnitude ML was derived. The magnitude–frequency distribution of a single longwall in Hamm was studied in detail and shows a maximum at ML = 1.4 corresponding to an estimated characteristic source area of about 2,200 m2. Sandstone layers in the hanging or foot wall of the active longwall might fail in these characteristic events. Source mechanisms can mostly be explained by shear failure of two different types above and below the longwall. Fault plane solutions of typical events are consistent with steeply dipping fracture planes parallel to the longwall face and nearly vertical dislocation in direction towards the goaf. We also derive an empirical relation for the decay of ground velocity with epicenter distance and compare maximum observed ground velocity to local magnitude. This is of considerable public interest because about 30 events larger than ML ≥ 1.2 are felt each month by people living in the mining regions. Our relations, for example, indicate that an event in Hamm with a peak ground velocity of 6 mm/s which corresponds to a local magnitude ML between 1.7 and 2.3 is likely to be felt within about 2.3 km radius from the event.

The crystal structure of the c-ring from the proton-coupled F1Fo ATP synthase from Spirulina platensis is shown at 2.1-A resolution. The ring includes 15 membrane-embedded c subunits forming an hourglass-shaped assembly. The structure demonstrates that proton translocation across the membrane entails protonation of a conserved glutamate located near the membrane center in the c subunit outer helix. The proton is locked in this site by a precise hydrogen bond network reminiscent of that in Na+-dependent ATP synthases. However, the structure suggests that the different coordination chemistry of the bound proton and the smaller curvature of the outer helix drastically enhance the selectivity of the H+ site against other cations, including H3O+. We propose a model for proton translocation whereby the c subunits remain in this proton-locked state when facing the membrane lipid. Proton exchange would occur in a more hydrophilic and electrostatically distinct environment upon contact with the a subunit interface.

This paper presents the numerical simulation of a creeping slope in Upper Austria, using a visco-hypoplastic material law which describes the mechanical behavior of cohesive soils allowing for viscous effects, i.e. creep and relaxation. The method consists of: (1) determination of the parameters of the material law, based on laboratory tests on soil samples taken from the slope; (2) simulation of the laboratory tests with an element test program in which the used material law was implemented, in order to test whether the model holds for the soils studied; and (3) simulation of slope movements at different sections along the slope, assuming an infinite slope. The simulation results fit well with the field measurements. This demonstrates that despite strongly simplified boundary conditions and limited availability of subsurface data (e.g. density) the visco-hypoplastic law is a promising tool for predicting creep movements.

Reagentless, oxygen-independent glucose biosensors based on an Os-complex-modified polypyrrole matrix and on soluble PQQ-dependent glucose dehydrogenase from Acinetobacter calcoaceticus are described.

The subcellular location of several nonribosomal nucleolar proteins was examined at various stages of mitosis in synchronized mammalian cell lines including HeLa, 3T3, COS-7 and HIV-1 Rev-expressing CMT3 cells. Nucleolar proteins B23, fibrillarin, nucleolin and p52 as well as U3 snoRNA were located partially in the peripheral regions of chromosomes from prometaphase to early telophase. However, these proteins were also found in large cytoplasmic particles, 1-2 microm in diameter, termed nucleolus-derived foci (NDF). The NDF reached maximum numbers (as many as 100 per cell) during mid- to late anaphase, after which their number declined to a few or none during late telophase. The decline in the number of NDF approximately coincided with the appearance of prenucleolar bodies and reforming nucleoli. The HIV-1 Rev protein and a mutant Rev protein defective in its nuclear export signal were also found in the NDF. The mutant Rev protein precisely followed the pattern of localization of the above nucleolar proteins, whereas the wild-type Rev did not enter nuclei until G1 phase. The nucleolar shuttling phosphoprotein Nopp140 did not follow the above pattern of localization during mitosis: it dispersed in the cytoplasm from prometaphase through early telophase and was not found in the NDF. Although the NDF and mitotic coiled bodies disappeared from the cytoplasm at approximately the same time during mitosis, protein B23 was not found in mitotic coiled bodies, nor was p80 coilin present in the NDF. These results suggest that a class of proteins involved in preribosomal RNA processing associate with chromosome periphery and with NDF as part of a system to conserve and deliver preexisting components to reforming nucleoli during mitosis.

Monoclonal antibodies (MAbs) are used to investigate molecules that are expressed during embryonic muscle differentiation and that may be involved in muscle pioneer and muscle attachment site formation. MAb F2A5 immunoreactivity appears in all muscle pioneers as soon as they extend processes, and continues in all muscle precursors. MAb 4H1 immunoreactivity is strongly expressed only after mesodermal cells have fused with the muscle pioneers; then it is concentrated at their growth-cone-like ends near developing attachment sites. During later embryonic development, MAb F2A5 and MAb 4H1 immunoreactivity become associated with the myofibrillar network. Biochemical experiments indicate that MAb 4H1 recognises a 47 kDa antigen, and MAb F2A5 recognises an 80 kDa antigen.

Antibodies against horseradish peroxidase (HRP) recognize a neural-tissue-specific carbohydrate moiety that is expressed on a complex set of developmentally regulated antigens in grasshopper, Drosophila and other insects. The functional role of the neural-specific carbohydrate has been investigated by mutant analysis in Drosophila where subtle defects in wing sensory axon projections have been reported. Here we extend the analysis of this neural-specific carbohydrate to the single cell level by focusing on identified brain interneurons in the grasshopper embryo. Immunological blocking experiments carried out in embryo culture show that the neural-specific carbohydrate is essential for correct axonal guidance of the identified interneurons. Functional block of the carbohydrate epitope causes major aberrations in growth cone guidance and axonal outgrowth in approximately 40% of the cases studied. This analysis reveals an important role of neural-specific glycoconjugate for correct axonal guidance of individual identified neurons.