Decreased expression of breast cancer resistance protein in the duodenum in patients with obstructive cholestasis

Background/Aims: The expression of transporters involved in bile acid homeostasis is differentially regulated during obstructive cholestasis. Since the drug efflux transporter breast cancer resistance protein (BCRP) is known to transport bile acids, we investigated whether duodenal BCRP expression could be altered during cholestasis. Methods: Using real-time RT-PCR analysis we determined mRNA expression levels in duodenal tissue of 19 cholestatic patients. Expression levels were compared to 14 healthy subjects. BCRP protein staining was determined in biopsies of 6 cholestatic and 6 healthy subjects by immunohistochemistry. Results: We found that in patients with obstructive cholestasis mean duodenal BCRP mRNA levels were significantly reduced to 53% and mean protein staining was reduced to 57%. Conclusions: BCRP, a transporter for bile acids and numerous drugs, appears to be down-regulated in the human duodenum during cholestasis. The clinical impact of these results has to be investigated in further studies. Copyright (c) 2006 S. Karger AG, Basel

Solare Wasserbehandlung mittels SOWARLA-Technik

Das Deutsche Zentrum für Luft- und Raumfahrt entwickelt zusammen mit den mittelständischen Firmen Hirschmann Laborgeräte GmbH und KACO Gerätetechnik GmbH solare Kollektoren und Anlagensteuerungen zur photokatalytischen Reinigung von Wasser mittels Sonnenlicht. Das Prinzip der solaren Wasserreinigung ist insbesondere für biologisch nicht behandelbare Wässer interessant und kann sowohl zur Vorbehandlung als auch zur vollständigen Behandlung eingesetzt werden

Volume Navigation with Contrast Enhanced Ultrasound and Image Fusion for Percutaneous Interventions: First Results

Percutaneous biopsies and drainages, even of small lesions involving complex access pathways, can be accomplished with a high success rate by using 3D real time image fusion together with real time needle tracking

Large tunable valley splitting in edge-free graphene quantum dots on boron nitride

Coherent manipulation of binary degrees of freedom is at the heart of modern quantum technologies. Graphene offers two binary degrees: the electron spin and the valley. Efficient spin control has been demonstrated in many solid state systems, while exploitation of the valley has only recently been started, yet without control on the single electron level. Here, we show that van-der Waals stacking of graphene onto hexagonal boron nitride offers a natural platform for valley control. We use a graphene quantum dot induced by the tip of a scanning tunneling microscope and demonstrate valley splitting that is tunable from -5 to +10 meV (including valley inversion) by sub-10-nm displacements of the quantum dot position. This boosts the range of controlled valley splitting by about one order of magnitude. The tunable inversion of spin and valley states should enable coherent superposition of these degrees of freedom as a first step towards graphene-based qubits

Polarization state of the optical near-field

The polarization state of the optical electromagnetic field lying several nanometers above complex dielectric structures reveals the intricate light-matter interaction that occurs in this near-field zone. This information can only be extracted from an analysis of the polarization state of the detected light in the near-field. These polarization states can be calculated by different numerical methods well-suited to near--field optics. In this paper, we apply two different techniques (Localized Green Function Method and Differential Theory of Gratings) to separate each polarisation component associated with both electric and magnetic optical near-fields produced by nanometer sized objects. The analysis is carried out in two stages: in the first stage, we use a simple dipolar model to achieve insight into the physical origin of the near-field polarization state. In the second stage, we calculate accurate numerical field maps, simulating experimental near-field light detection, to supplement the data produced by analytical models. We conclude this study by demonstrating the role played by the near-field polarization in the formation of the local density of states.Comment: 9 pages, 11 figures, accepted for publication in Phys. Rev.

Doubling the mobility of InAs/InGaAs selective area grown nanowires

Selective area growth (SAG) of nanowires and networks promise a route toward scalable electronics, photonics, and quantum devices based on III-V semiconductor materials. The potential of high-mobility SAG nanowires however is not yet fully realised, since interfacial roughness, misfit dislocations at the nanowire/substrate interface and nonuniform composition due to material intermixing all scatter electrons. Here, we explore SAG of highly lattice-mismatched InAs nanowires on insulating GaAs(001) substrates and address these key challenges. Atomically smooth nanowire/substrate interfaces are achieved with the use of atomic hydrogen (a-H) as an alternative to conventional thermal annealing for the native oxide removal. The problem of high lattice mismatch is addressed through an InxGa1-xAs buffer layer introduced between the InAs transport channel and the GaAs substrate. The Ga-In material intermixing observed in both the buffer layer and the channel is inhibited via careful tuning of the growth temperature. Performing scanning transmission electron microscopy and x-ray diffraction analysis along with low-temperature transport measurements we show that optimized In-rich buffer layers promote high-quality InAs transport channels with the field-effect electron mobility over 10 000 cm2 V-1 s-1. This is twice as high as for nonoptimized samples and among the highest reported for InAs selective area grown nanostructures.The project was supported by Microsoft Quantum, the European Research Council (ERC) under Grant No. 716655 (HEMs-DAM), and the European Union Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant No. 722176. The authors acknowledge Dr. Keita Ohtani for technical support and fruitful discussions. D.V.B. is grateful to Dr. Juan-Carlos Estrada Saldaña for careful reading of the manuscript. The authors thank Francesco Montalenti, Marco Albani and Leo Miglio for scientific discussions. ICN2 acknowledges funding from Generalitat de Catalunya 2017 SGR 327. ICN2 is supported by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706) and is funded by the CERCA Programme/Generalitat de Catalunya. Part of the present work has been performed in the framework of Universitat Autònoma de Barcelona Materials Science Ph.D. program. The HAADF-STEM microscopy was conducted in the Laboratorio de Microscopias Avanzadas at Instituto de Nanociencia de Aragon-Universidad de Zaragoza. M.C.S. has received funding from the European Unionâs Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Grant Agreement No. 754510 (PROBIST). The funding agency is Consejo Superior de Investigaciones Científicas (CSIC) and the project reference is “Research Platform on Quantum Technologies PTI-001”

Hospitalized patients dying with SARS-CoV-2 infection—an analysis of patient characteristics and management in ICU and general ward of the LEOSS registry

BACKGROUND: COVID-19 is a severe disease with a high need for intensive care treatment and a high mortality rate in hospitalized patients. The objective of this study was to describe and compare the clinical characteristics and the management of patients dying with SARS-CoV-2 infection in the acute medical and intensive care setting. METHODS: Descriptive analysis of dying patients enrolled in the Lean European Open Survey on SARS-CoV-2 Infected Patients (LEOSS), a non-interventional cohort study, between March 18 and November 18, 2020. Symptoms, comorbidities and management of patients, including palliative care involvement, were compared between general ward and intensive care unit (ICU) by univariate analysis. RESULTS: 580/4310 (13%) SARS-CoV-2 infected patients died. Among 580 patients 67% were treated on ICU and 33% on a general ward. The spectrum of comorbidities and symptoms was broad with more comorbidities (≥ four comorbidities: 52% versus 25%) and a higher age distribution (>65 years: 98% versus 70%) in patients on the general ward. 69% of patients were in an at least complicated phase at diagnosis of the SARS-CoV-2 infection with a higher proportion of patients in a critical phase or dying the day of diagnosis treated on ICU (36% versus 11%). While most patients admitted to ICU came from home (71%), patients treated on the general ward came likewise from home and nursing home (44% respectively) and were more frequently on palliative care before admission (29% versus 7%). A palliative care team was involved in dying patients in 15%. Personal contacts were limited but more often documented in patients treated on ICU (68% versus 47%). CONCLUSION: Patients dying with SARS-CoV-2 infection suffer from high symptom burden and often deteriorate early with a demand for ICU treatment. Therefor a demand for palliative care expertise with early involvement seems to exist

Diffusion of peroxides through dentine in vitro with and without prior use of a desensitizing varnish

Different bleaching regimens are used in dentistry possibly penetrating the dentine and affecting the pulp. The aim of the present study was to investigate peroxide diffusion through dentine pre-treated with a desensitizing varnish (Vivasens®) in a standardized in vitro setup during application of different bleaching materials. The penetration was tested using 1.3-mm-thick bovine dentine slabs. The following bleaching materials were tested with and without prior application of the desensitizing varnish on the external side of the dentine slabs: Vivastyle, Whitestrips, Simply White, Opalescence (external bleaching), and sodium perborate (internal bleaching, only tested without varnish; n = 8 samples per subgroup). The penetration of peroxides was measured photometrically using 4-aminoantipyrin as a substrate, the penetration of peroxides was monitored over 240 min. All bleaching agents yielded a diffusion of peroxides through the dentine, the kinetics of penetration were approximately linear for all materials tested. The significantly highest diffusion of peroxides was observed with Opalescence, the lowest with sodium perborate. The adoption of the desensitizing varnish reduced the diffusion of peroxides significantly for all external bleaching materials. Peroxides penetrated the dentine during application of bleaching materials; the penetration of peroxides can be reduced by application of a desensitizing agent

Dynamics of urinary and respiratory shedding of Severe acute respiratory syndrome virus 2 (SARS-CoV-2) RNA excludes urine as a relevant source of viral transmission

PURPOSE To investigate the expression of the receptor protein ACE-2 alongside the urinary tract, urinary shedding and urinary stability of SARS-CoV-2 RNA. METHODS Immunohistochemical staining was performed on tissue from urological surgery of 10 patients. Further, patients treated for coronavirus disease (COVID-19) at specialized care-units of a university hospital were assessed for detection of SARS-CoV-2 RNA in urinary samples via PCR, disease severity (WHO score), inflammatory response of patients. Finally, the stability of SARS-CoV-2 RNA in urine was analyzed. RESULTS High ACE-2 expression (3/3) was observed in the tubules of the kidney and prostate glands, moderate expression in urothelial cells of the bladder (0-2/3) and no expression in kidney glomeruli, muscularis of the bladder and stroma of the prostate (0/3). SARS-CoV-2 RNA was detected in 5/199 urine samples from 64 patients. Viral RNA was detected in the first urinary sample of sequential samples. Viral RNA load from other specimen as nasopharyngeal swabs (NPS) or endotracheal aspirates revealed higher levels than from urine. Detection of SARS-CoV-2 RNA in urine was not associated with impaired WHO score (median 5, range 3-8 vs median 4, range 1-8, p = 0.314), peak white blood cell count (median 24.1 × 1000/ml, range 5.19-48.1 versus median 11.9 × 1000/ml, range 2.9-60.3, p = 0.307), peak CRP (median 20.7~mg/dl, 4.2-40.2 versus median 11.9~mg/dl, range 0.1-51.9, p = 0.316) or peak IL-6 levels (median: 1442~ng/ml, range 26.7-3918 versus median 140~ng/ml, range 3.0-11,041, p = 0.099). SARS-CoV-2 RNA was stable under different storage conditions and after freeze-thaw cycles. CONCLUSIONS SARS-CoV-2 RNA in the urine of COVID-19 patients occurs infrequently. The viral RNA load and dynamics of SARS-CoV-2 RNA shedding suggest no relevant route of transmission through the urinary tract