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The aim of this study was to test the removability of fully covered self-expandable metal stents (FCSEMS) in patients with a benign common bile duct (CBD) stricture. A FCSEMS was inserted in six patients with a CBD stricture due to chronic pancreatitis who were considered to be unfit for surgery, and stent removal was attempted after predefined intervals of 4 and 6 months. FCSEMS were successfully placed in all patients (100?% placement success) and stent extraction was accomplished in four patients (66?% removal rate), all of whom achieved stricture resolution (66?% resolution rate). In one patient a recurrent stenosis developed after 6 months (recurrence rate 25?%). Proximal stent migration occurred in two patients. In conclusion, FCSEMS removal was possible in the majority of patients and results regarding stricture dilation were promising. Nevertheless, before FCSEMS can become an acceptable treatment option for benign CBD strictures, innovative stent design modifications are necessary and removability must be ascertained. [ABSTRACT FROM AUTHOR]

Pancreatic exocrine insufficiency (PEI) is defined as a reduction in pancreatic exocrine secretion below the level that allows the normal digestion of nutrients. Pancreatic disease and surgery are the main causes of PEI. However, other conditions and upper gastrointestinal surgery can also affect the digestive function of the pancreas. PEI can cause symptoms of nutritional malabsorption and deficiencies, which affect the quality of life and increase morbidity and mortality. These guidelines were developed following the United European Gastroenterology framework for the development of high-quality clinical guidelines. After a systematic literature review, the evidence was evaluated according to the Oxford Center for Evidence-Based Medicine and the Grading of Recommendations Assessment, Development, and Evaluation methodology, as appropriate. Statements and comments were developed by the working groups and voted on using the Delphi method. The diagnosis of PEI should be based on a global assessment of symptoms, nutritional status, and a pancreatic secretion test. Pancreatic enzyme replacement therapy (PERT), together with dietary advice and support, are the cornerstones of PEI therapy. PERT is indicated in patients with PEI that is secondary to pancreatic disease, pancreatic surgery, or other metabolic or gastroenterological conditions. Specific recommendations concerning the management of PEI under various clinical conditions are provided based on evidence and expert opinions. This evidence-based guideline summarizes the prevalence, clinical impact, and general diagnostic and therapeutic approaches for PEI, as well as the specifics of PEI in different clinical conditions. Finally, the unmet needs for future research are discussed., (© 2024 The Author(s). United European Gastroenterology Journal published by Wiley Periodicals LLC on behalf of United European Gastroenterology.)

Proteins are attractive as functional components in molecular junctions. However, controlling the electronic charge transport via proteins, held between two electrodes, requires information on their frontier orbital energy level alignment relative to the electrodes' Fermi level (E F ), which normally requires studies of UV Photoemission Spectroscopy (UPS) with HeI excitation. Such excitation is problematic for proteins, which can denature under standard measuring conditions. Here high-sensitivity soft UV photoemission spectroscopy (HS-UPS) combined with Constant Final State Yield Spectroscopy (CFS-YS) is used to get this information for electrode/protein contacts. Monolayers of the redox protein Azurin, (Az) and its Apo-form on Au substrates, have HOMO onset energies, obtained from CFS-YS, differ by ≈0.2 eV, showing the crucial role of the Cu redox centre in the electron transport process. It is found that combined HS-UPS/CFS-YS measurements agree with the Photoelectron Yield Spectroscopy (PYS), showing potential of the HS-UPS + CFS-YS as a powerful tool to characterize and map the energetics of a protein-electrode interfaces, which will aid optimizing design of devices with targeted electronic properties, as well as for novel applications., (© 2024 Wiley‐VCH GmbH.)

The (opto)electronic behavior of semiconductors depends on their (quasi-)free electronic carrier densities. These are regulated by semiconductor doping, i.e., controlled "electronic contamination". For metal halide perovskites (HaPs), the functional materials in several device types, which already challenge some of the understanding of semiconductor properties, this study shows that doping type, density and properties derived from these, are to a first approximation controlled via their surfaces. This effect, relevant to all semiconductors, and already found for some, is very evident for lead (Pb)-HaPs because of their intrinsically low electrically active bulk and surface defect densities. Volume carrier densities for most polycrystalline Pb-HaP films (<1 µm grain diameter) are below those resulting from even < 0.1% of surface sites being electrically active defects. This implies and is consistent with interfacial defects controlling HaP devices in multi-layered structures with most of the action at the two HaP interfaces. Surface and interface passivation effects on bulk electrical properties are relevant to all semiconductors and are crucial for developing those used today. However, because bulk dopant introduction in HaPs at controlled ppm levels for electronic-relevant carrier densities is so difficult, passivation effects are vastly more critical and dominate, to first approximation, their optoelectronic characteristics in devices., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Self-healing materials can become game changers for developing sustainable (opto)electronics. APbX 3 halide (=X - ) perovskites, HaPs, have shown a remarkable ability to self-heal damage. While we demonstrated self-healing in pure HaP compounds, in single crystals, and in polycrystalline thin films (as used in most devices), HaP compositions with multiple A + (and X - ) constituents are preferred for solar cells. We now show self-healing in mixed A + HaPs. Specifically, if at least 15 atom % of the methylammonium (MA + ) A cation is substituted for by guanidinium (Gua + ) or acetamidinium (AA + ), then the self-healing rate after damage is enhanced. In contrast, replacing MA + with dimethylammonium (DMA + ), comparable in size to Gua + or AA + , does not alter this rate. Based on the times for self-healing, we infer that the rate-determining step involves short-range diffusion of A + and/or Pb 2+ cations and that the self-healing rate correlates with the strain in the material, the A + cation dipole moment, and H-bonding between A + and I - . These insights may offer clues for developing a detailed self-healing mechanism and understanding the kinetics to guide the design of self-healing materials. Fast recovery kinetics are important from the device perspective, as they allow complete recovery in devices during operation or when switched off (LEDs)/in the dark (photovoltaics)., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The fundamental question of "what is the transport path of electrons through proteins?" initially introduced while studying long-range electron transfer between localized redox centers in proteins in vivo is also highly relevant to the transport properties of solid-state, dry metal-protein-metal junctions. Here, we report conductance measurements of such junctions, Au-( Azurin monolayer ensemble)-Bismuth (Bi) ones, with well-defined nanopore geometry and ~10 3 proteins/pore. Our results can be understood as follows. (1) Transport is via two interacting conducting channels, characterized by different spatial and time scales. The slow and spatially localized channel is associated with the Cu center of Azurin and the fast delocalized one with the protein's polypeptide matrix. Transport via the slow channel is by a sequential (noncoherent) process and in the second one by direct, off-resonant tunneling. (2) The two channels are capacitively coupled. Thus, with a change in charge occupation of the weakly coupled (metal center) channel, the broad energy level manifold, responsible for off-resonance tunneling, shifts, relative to the electrodes' Fermi levels. In this process, the off-resonance (fast) channel dominates transport, and the slow (redox) channel, while contributing only negligibly directly, significantly affects transport by intramolecular gating., Competing Interests: Competing interests statement:The authors declare no competing interest.

The term defect tolerance (DT) is used often to rationalize the exceptional optoelectronic properties of halide perovskites (HaPs) and their devices. Even though DT lacked direct experimental evidence, it became a "fact" in the field. DT in semiconductors implies that structural defects do not translate to electrical and optical effects (e.g., due to charge trapping), associated with such defects. We present pioneering direct experimental evidence for DT in Pb-HaPs by comparing the structural quality of 2-dimensional (2D), 2D-3D, and 3D Pb-iodide HaP crystals with their optoelectronic characteristics using high-sensitivity methods. Importantly, we get information from the materials' bulk because we sample at least a few hundred nanometers, up to several micrometers, from the sample's surface, which allows for assessing intrinsic bulk (and not only surface-) properties of HaPs. The results point to DT in 3D, 2D-3D, and 2D Pb-HaPs. Overall, our data provide an experimental basis to rationalize DT in Pb-HaPs. These experiments and findings will help the search for and design of materials with real DT., Competing Interests: Competing interests statement:The authors declare no competing interest.

Research in prehospital and in-hospital emergency medicine is essential to the development of this discipline. By calling certain practices into question (thrombolysis for minor strokes, use of coagulation factors for patients with severe polytrauma), providing access to new technologies (video-laryngoscopy, POCT troponins in pre-hospital care) or questioning new practices (double defibrillation, pulmonary US in pneumonia), research enables emergency physicians to adapt their day-to-day practice., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêts en relation avec cet article.

A key conundrum of biomolecular electronics is efficient electron transport (ETp) through solid-state junctions up to 10 nm, often without temperature activation. Such behavior challenges known charge transport mechanisms, especially via nonconjugated molecules such as proteins. Single-step, coherent quantum-mechanical tunneling proposed for ETp across small protein, 2-3 nm wide junctions, but it is problematic for larger proteins. Here we exploit the ability of bacteriorhodopsin (bR), a well-studied, 4-5 nm long membrane protein, to assemble into well-defined single and multiple bilayers, from ∼9 to 60 nm thick, to investigate ETp limits as a function of junction width. To ensure sufficient signal/noise, we use large area (∼10 -3 cm 2 ) Au-protein-Si junctions. Photoemission spectra indicate a wide energy separation between electrode Fermi and the nearest protein-energy levels, as expected for a polymer of mostly saturated components. Junction currents decreased exponentially with increasing junction width, with uniquely low length-decay constants (0.05-0.5 nm -1 ). Remarkably, even for the widest junctions, currents are nearly temperature-independent, completely so below 160 K. While, among other things, the lack of temperature-dependence excludes, hopping as a plausible mechanism, coherent quantum-mechanical tunneling over 60 nm is physically implausible. The results may be understood if ETp is limited by injection into one of the contacts, followed by more efficient charge propagation across the protein. Still, the electrostatics of the protein films further limit the number of charge carriers injected into the protein film. How electron transport across dozens of nanometers of protein layers is more efficient than injection defines a riddle, requiring further study.