Sedimentation of large, soluble proteins up to 140 kDa for 1H-detected MAS NMR and 13C DNP NMR - practical aspects.

Solution NMR is typically applied to biological systems with molecular weights < 40 kDa whereas magic-angle-spinning (MAS) solid-state NMR traditionally targets very large, oligomeric proteins and complexes exceeding 500 kDa in mass, including fibrils and crystalline protein preparations. Here, we propose that the gap between these size regimes can be filled by the approach presented that enables investigation of large, soluble and fully protonated proteins in the range of 40-140 kDa. As a key step, ultracentrifugation produces a highly concentrated, gel-like state, resembling a dense phase in spontaneous liquid-liquid phase separation (LLPS). By means of three examples, a Sulfolobus acidocaldarius bifurcating electron transfer flavoprotein (SaETF), tryptophan synthases from Salmonella typhimurium (StTS) and their dimeric ß-subunits from Pyrococcus furiosus (PfTrpB), we show that such samples yield well-resolved proton-detected 2D and 3D NMR spectra at 100 kHz MAS without heterogeneous broadening, similar to diluted liquids. Herein, we provide practical guidance on centrifugation conditions and tools, sample behavior, and line widths expected. We demonstrate that the observed chemical shifts correspond to those obtained from µM/low mM solutions or crystalline samples, indicating structural integrity. Nitrogen line widths as low as 20-30 Hz are observed. The presented approach is advantageous for proteins or nucleic acids that cannot be deuterated due to the expression system used, or where relevant protons cannot be re-incorporated after expression in deuterated medium, and it circumvents crystallization. Importantly, it allows the use of low-glycerol buffers in dynamic nuclear polarization (DNP) NMR of proteins as demonstrated with the cyanobacterial phytochrome Cph1.

The metaphorical swiss army knife: The multitude and diverse roles of HEAT domains in eukaryotic translation initiation.

Biomolecular associations forged by specific interaction among structural scaffolds are fundamental to the control and regulation of cell processes. One such structural architecture, characterized by HEAT repeats, is involved in a multitude of cellular processes, including intracellular transport, signaling, and protein synthesis. Here, we review the multitude and versatility of HEAT domains in the regulation of mRNA translation initiation. Structural and cellular biology approaches, as well as several biophysical studies, have revealed that a number of HEAT domain-mediated interactions with a host of protein factors and RNAs coordinate translation initiation. We describe the basic structural architecture of HEAT domains and briefly introduce examples of the cellular processes they dictate, including nuclear transport by importin and RNA degradation. We then focus on proteins in the translation initiation system featuring HEAT domains, specifically the HEAT domains of eIF4G, DAP5, eIF5, and eIF2Bϵ. Comparative analysis of their remarkably versatile interactions, including protein-protein and protein-RNA recognition, reveal the functional importance of flexible regions within these HEAT domains. Here we outline how HEAT domains orchestrate fundamental aspects of translation initiation and highlight open mechanistic questions in the area.

Osmotically Delaminated Silicate Nanosheet-Coated NCM for Ultra-Stable Li+ Storage and Chemical Stability Toward Long-Term Air Exposure.

To ensure the safety and performance of lithium-ion batteries (LIBs), a rational design and optimization of suitable cathode materials are crucial. Lithium nickel cobalt manganese oxides (NCM) represent one of the most popular cathode materials for commercial LIBs. However, they are limited by several critical issues, such as transition metal dissolution, formation of an unstable cathode-electrolyte interphase (CEI) layer, chemical instability upon air exposure, and mechanical instability. In this work, coating fabricated by self-assembly of osmotically delaminated sodium fluorohectorite (Hec) nanosheets onto NCM (Hec-NCM) in a simple and technically benign aqueous wet-coating process is reported first. Complete wrapping of NCM by high aspect ratio (>10 000) nanosheets is enabled through an electrostatic attraction between Hec nanosheets and NCM as well as by the superior mechanical flexibility of Hec nanosheets. The coating significantly suppresses mechanical degradation while forming a multi-functional CEI layer. Consequently, Hec-NCM delivers outstanding capacity retention for 300 cycles. Furthermore, due to the exceptional gas barrier properties of the few-layer Hec-coating, the electrochemical performance of Hec-NCM is maintained even after 6 months of exposure to the ambient atmosphere. These findings suggest a new direction of significantly improving the long-term stability and activity of cathode materials by creating an artificial CEI layer.

Performance-Based Screening of Porous Materials for Carbon Capture.

Computational screening methods have changed the way new materials and processes are discovered and designed. For adsorption-based gas separations and carbon capture, recent efforts have been directed toward the development of multiscale and performance-based screening workflows where we can go from the atomistic structure of an adsorbent to its equilibrium and transport properties at different scales, and eventually to its separation performance at the process level. The objective of this work is to review the current status of this new approach, discuss its potential and impact on the field of materials screening, and highlight the challenges that limit its application. We compile and introduce all the elements required for the development, implementation, and operation of multiscale workflows, hence providing a useful practical guide and a comprehensive source of reference to the scientific communities who work in this area. Our review includes information about available materials databases, state-of-the-art molecular simulation and process modeling tools, and a complete catalogue of data and parameters that are required at each stage of the multiscale screening. We thoroughly discuss the challenges associated with data availability, consistency of the models, and reproducibility of the data and, finally, propose new directions for the future of the field.

Indole Diketopiperazine Alkaloids from the Marine Sediment-Derived Fungus Aspergillus chevalieri against Pancreatic Ductal Adenocarcinoma.

A new prenylated indole diketopiperazine alkaloid, rubrumline P (1), was isolated along with six more analogues and characterized from the fermentation culture of a marine sediment-derived fungus, Aspergillus chevalieri, collected at a depth of 15 m near the lighthouse in Dahab, Red Sea, Egypt. In the current study, a bioassay-guided fractionation allowed for the identification of an active fraction displaying significant cytotoxic activity against the human pancreatic adenocarcinoma cell line PANC-1 from the EtOAc extract of the investigated fungus compared to the standard paclitaxel. The structures of the isolated compounds from the active fraction were established using 1D/2D NMR spectroscopy and mass spectrometry, together with comparisons with the literature. The absolute configuration of the obtained indole diketopiperazines was established based on single-crystal X-ray diffraction analyses of rubrumline I (2) and comparisons of optical rotations and NMR data, as well as on biogenetic considerations. Genome sequencing indicated the formation of prenyltransferases, which was subsequently confirmed by the isolation of mono-, di-, tri-, and tetraprenylated compounds. Compounds rubrumline P (1) and neoechinulin D (4) confirmed preferential cytotoxic activity against PANC-1 cancer cells with IC50 values of 25.8 and 23.4 µM, respectively. Although the underlying mechanism-of-action remains elusive in this study, cell cycle analysis indicated a slight increase in the sub-G1 peak after treatment with compounds 1 and 4.

Thick-Layer Lead Iodide Perovskites with Bifunctional Organic Spacers Allylammonium and Iodopropylammonium Exhibiting Trap-State Emission.

The nature of the organic cation in two-dimensional (2D) hybrid lead iodide perovskites tailors the structural and technological features of the resultant material. Herein, we present three new homologous series of (100) lead iodide perovskites with the organic cations allylammonium (AA) containing an unsaturated C═C group and iodopropylammonium (IdPA) containing iodine on the organic chain: (AA)2MAn-1PbnI3n+1 (n = 3-4), [(AA)x(IdPA)1-x]2MAn-1PbnI3n+1 (n = 1-4), and (IdPA)2MAn-1PbnI3n+1 (n = 1-4), as well as their perovskite-related substructures. We report the in situ transformation of AA organic layers into IdPA and the incorporation of these cations simultaneously into the 2D perovskite structure. Single-crystal X-ray diffraction shows that (AA)2MA2Pb3I10 crystallizes in the space group P21/c with a unique inorganic layer offset (0, <1/2), comprising the first example of n = 3 halide perovskite with a monoammonium cation that deviates from the Ruddlesden-Popper (RP) halide structure type. (IdPA)2MA2Pb3I10 and the alloyed [(AA)x(IdPA)1-x]2MA2Pb3I10 crystallize in the RP structure, both in space group P21/c. The adjacent I···I interlayer distance in (AA)2MA2Pb3I10 is ∼5.6 Å, drawing the [Pb3I10]4- layers closer together among all reported n = 3 RP lead iodides. (AA)2MA2Pb3I10 presents band-edge absorption and photoluminescence (PL) emission at around 2.0 eV that is slightly red-shifted in comparison to (IdPA)2MA2Pb3I10. The band structure calculations suggest that both (AA)2MA2Pb3I10 and (IdPA)2MA2Pb3I10 have in-plane effective masses around 0.04m0 and 0.08m0, respectively. IdPA cations have a greater dielectric contribution than AA. The excited-state dynamics investigated by transient absorption (TA) spectroscopy reveal a long-lived (∼100 ps) trap state ensemble with broad-band emission; our evidence suggests that these states appear due to lattice distortions induced by the incorporation of IdPA cations.

AInSn2S6 (A = K, Rb, Cs)─Layered Semiconductors Based on the SnS2 Structure.

RbInSn2S6 and CsInSn2S6 are yellow two-dimensional (2D) semiconductors featuring anionic SnS2-type layers of edge-sharing (In/Sn)S6 octahedra. These structures are directly derived from the parent structure of SnS2 by replacement of Sn4+ atoms with A+ and In3+ atoms. The compounds crystallize, isotypic to the ion-exchange material KInSn2S6. They adopt the triclinic space group R3̅m (no. 166). The compounds have similar indirect optical band gaps of 2.31(5) eV for Rb and 2.47(5) eV Cs. The measured work functions for each material are ∼5.38 eV. The density functional theory-calculated effective mass values exhibit strong anisotropy due to the 2D nature of the crystal structures and in the case of CsInSn2S6 for hole carriers along the a, b, and c crystallographic directions are 0.30 m0, 0.34 m0, and 2.54 m0, respectively, while for electrons are 0.06 m0, 0.07 m0, and 0.47 m0, respectively.

[Medical Necessity: A Notoriously Fuzzy and Therefore Dispensable Concept?] / Medizinische Notwendigkeit: Ein entbehrlicher, da notorisch unscharfer Begriff?

The concept of a 'medical necessity' (medN) of interventions is used as a dichotomous attribute with steering and orientating function in various contexts without, however, being precisely defined. We see this lack as a virtue if medN is understood as the dynamic result of transparent, trustworthy, and coherent deliberative procedures on both facts and norms. We suggest using the medN concept relative to health care systems, but independent of economic aspects.

PaOctß2R: Identification and Functional Characterization of an Octopamine Receptor Activating Adenylyl Cyclase Activity in the American Cockroach Periplaneta americana.

Biogenic amines constitute an important group of neuroactive substances that control and modulate various neural circuits. These small organic compounds engage members of the guanine nucleotide-binding protein coupled receptor (GPCR) superfamily to evoke specific cellular responses. In addition to dopamine- and 5-hydroxytryptamine (serotonin) receptors, arthropods express receptors that are activated exclusively by tyramine and octopamine. These phenolamines functionally substitute the noradrenergic system of vertebrates Octopamine receptors that are the focus of this study are classified as either α- or ß-adrenergic-like. Knowledge on these receptors is scarce for the American cockroach (Periplaneta americana). So far, only an α-adrenergic-like octopamine receptor that primarily causes Ca2+ release from intracellular stores has been studied from the cockroach (PaOctα1R). Here we succeeded in cloning a gene from cockroach brain tissue that encodes a ß-adrenergic-like receptor and leads to cAMP production upon activation. Notably, the receptor is 100-fold more selective for octopamine than for tyramine. A series of synthetic antagonists selectively block receptor activity with epinastine being the most potent. Bioinformatics allowed us to identify a total of 19 receptor sequences that build the framework of the biogenic amine receptor clade in the American cockroach. Phylogenetic analyses using these sequences and receptor sequences from model organisms showed that the newly cloned gene is an ß2-adrenergic-like octopamine receptor. The functional characterization of PaOctß2R and the bioinformatics data uncovered that the monoaminergic receptor family in the hemimetabolic P. americana is similarly complex as in holometabolic model insects like Drosophila melanogaster and the honeybee, Apis mellifera. Thus, investigating these receptors in detail may contribute to a better understanding of monoaminergic signaling in insect behavior and physiology.

Comparative analysis of sustainability measures in the apparel industry: An empirical consumer and market study in Germany.

The pressure on the apparel industry to make its products more sustainable is growing. Concrete measures have hardly been taken so far, also because they aim to avoid consumption which reduces profits. Studies mostly examine impacts on the environment, but not how the market volume can remain at a maximum for producers. To uncover direct market effects from sustainability approaches, this study asked 500 German consumers about their willingness-to-pay and preference order for three different measures, namely "slowing in consumption", "recyclability of petrochemical clothing" or its "production from bioplastics". An outdoor trekking jacket served as test object, and influences from sociodemographic and latent variables, as sportiness and environmental awareness, were measured. The results were mapped in a market model from which the output volume was derived. It was found that interest in the topic of plastics-containing outdoor clothing was rather determined by the application. This increased with the sportiness of the respondents (r = 0.13; p = 0.003), but not with their personal environmental awareness. Consent to bioplastics use did not depend on the level of experience, but older consumers appreciated this option more (p = 0.027). Only 20% of the respondents favoured slowing, 26% bioplastics, but 53% recycling of petroplastics. Therefore, research should investigate recyclability, policy should support this measure, and companies should practice take-back and reuse in new clothing. Consumers can maintain fast consumption and would even accept higher prices.

Layered and Cubic Semiconductors AGaM'Q4 (A+ = K+, Rb+, Cs+, Tl+; M'4+ = Ge4+, Sn4+; Q2- = S2-, Se2-) and High Third-Harmonic Generation.

Eighteen new quaternary chalcogenides AGaM'Q4 (A+ = K+, Rb+, Cs+, Tl+; M'4+ = Ge4+, Sn4+; Q2- = S2-, Se2-) have been prepared by solid-state syntheses and structurally characterized using single-crystal X-ray diffraction techniques. These new phases crystallize in a variety of layered structure types. The tin analogues also adopt an extended three-dimensional network structure as polymorphs. The polymorphism and phase-stability in these cases were studied by thermal analysis and high-temperature in situ X-ray powder diffraction. All compounds are semiconductors with the colored selenides absorbing light in the infrared-green region (1.8 eV < Eg < 2.3 eV) and the mostly white sulfides absorbing light in the blue-ultraviolet range (2.5 eV < Eg < 3.6 eV). Based on third-harmonic generation (THG) measurements, the third-order nonlinear optical (NLO) susceptibilities χ(3) of the new and previously reported AGaM'Q4 compounds were determined. These measurements revealed an apparent correlation between the THG response of the sample and its band gap, rather than the crystal structure type. While low-gap materials possess higher nonlinearity in general, we found that layered orthorhombic RbGaGeS4 exhibits an impressive χ(3) value (about four times larger than that of AgGaS2) even with a large band gap and shows stability under ambient conditions with no significant irradiation damage.

MAS NMR detection of hydrogen bonds for protein secondary structure characterization.

Hydrogen bonds are essential for protein structure and function, making experimental access to long-range interactions between amide protons and heteroatoms invaluable. Here we show that measuring distance restraints involving backbone hydrogen atoms and carbonyl- or α-carbons enables the identification of secondary structure elements based on hydrogen bonds, provides long-range contacts and validates spectral assignments. To this end, we apply specifically tailored, proton-detected 3D (H)NCOH and (H)NCAH experiments under fast magic angle spinning (MAS) conditions to microcrystalline samples of SH3 and GB1. We observe through-space, semi-quantitative correlations between protein backbone carbon atoms and multiple amide protons, enabling us to determine hydrogen bonding patterns and thus to identify ß-sheet topologies and α-helices in proteins. Our approach shows the value of fast MAS and suggests new routes in probing both secondary structure and the role of functionally-relevant protons in all targets of solid-state MAS NMR.

pH-Dependent Protonation of Surface Carboxylate Groups in PsbO Enables Local Buffering and Triggers Structural Changes.

Photosystem II (PSII) catalyzes the splitting of water, releasing protons and dioxygen. Its highly conserved subunit PsbO extends from the oxygen-evolving center (OEC) into the thylakoid lumen and stabilizes the catalytic Mn4 CaO5 cluster. The high degree of conservation of accessible negatively charged surface residues in PsbO suggests additional functions, as local pH buffer or by affecting the flow of protons. For this discussion, we provide an experimental basis, through the determination of pKa values of water-accessible aspartate and glutamate side-chain carboxylate groups by means of NMR. Their distribution is strikingly uneven, with high pKa values around 4.9 clustered on the luminal PsbO side and values below 3.5 on the side facing PSII. pH-dependent changes in backbone chemical shifts in the area of the lumen-exposed loops are observed, indicating conformational changes. In conclusion, we present a site-specific analysis of carboxylate group proton affinities in PsbO, providing a basis for further understanding of proton transport in photosynthesis.

Spatial Variations in Femtosecond Field Dynamics within a Plasmonic Nanoresonator Mode.

Plasmonic resonators can be designed to support spectrally well-separated discrete modes. The associated characteristic spatial patterns of intense electromagnetic hot-spots can be exploited to enhance light-matter interaction. Here, we study the local field dynamics of individual hot-spots within a nanoslit resonator by detecting characteristic changes of the photoelectron emission signal on a scale of ∼12 nm using time-resolved photoemission electron microscopy (TR-PEEM) and by excitation with the output from a 20 fs, 1 MHz noncollinear optical parametric amplifier (NOPA). Surprisingly, we detect apparent spatial variations of the Q-factor and resonance frequency that are commonly considered to be global properties for a single mode. By using the concept of quasinormal modes we explain these local differences by crosstalk of adjacent resonator modes. Our findings are important in view of time-domain studies of plasmon-mediated strong light-matter coupling at ambient conditions.

Nonclassical Optical Properties of Mesoscopic Gold.

Gold nanostructures have important applications in nanoelectronics, nano-optics, and in precision metrology due to their intriguing optoelectronic properties. These properties are governed by the bulk band structure but to some extent are tunable via geometrical resonances. Here we show that the band structure of gold itself exhibits significant size-dependent changes already for mesoscopic critical dimensions below 30 nm. To suppress the effects of geometrical resonances and grain boundaries, we prepared atomically flat ultrathin films of various thicknesses by utilizing large chemically grown single-crystalline gold platelets. We experimentally probe thickness-dependent changes of the band structure by means of two-photon photoluminescence and observe a surprising 100-fold increase of the nonlinear signal when the gold film thickness is reduced below 30 nm allowing us to optically resolve single-unit-cell steps. The effect is well explained by density functional calculations of the thickness-dependent 2D band structure of gold.

[Medical Methods: What Makes them Necessary? Part I: Medical Methods, medical Necessity and its Main Criteria]. / Medizinische Behandlungsmethoden: Was macht sie medizinisch notwendig? Teil I: Medizinische Methoden, medizinische Notwendigkeit und ihre Hauptkriterien.

OBJECTIVES: "Medical necessity" (MedN) is a fuzzy term. Our project aims at concretising the concept between medical ethics, social law, and social medicine to support health care regulation, primarily within Germany's statutory health insurance system. In a previous publication we identified MedN as a tripartite predicate: A specific clinical condition requires a specific medical intervention to reach a specific medical goal. Our two-part text searches for and discusses criteria to classify medical methods as generally medically necessary (medn), provided a non-trivial clinical condition and a relevant, legitimate, and reachable goal actually exist. In this paper we present the first part of our results. METHODS: Based on an extensive ethical, sociolegal and sociomedical body of literature, and starting with an non-controversial case vignette (thrombolysis in acute stroke), we generally followed a critical reconstructive approach. First we defined the term "medical method". In several interdisciplinary rounds, we then collected and discussed criteria from three sources: methods to develop clinical practice guidelines as compendia of indication rules, the National Model of Prioritisation in Swedish Health Care, and the HTA Core Model of the European Network for Health Technology Assessment as an instrument of political counselling. RESULTS: We identified general clinical efficacy and benefit as the 2 main "medical" criteria of MedN. As a third - epistemic - criterion, the corresponding bodies of evidence are always to be considered. Since clinical and prioritising guidelines grade their recommendations, the question arises whether MedN should be conceptualised as a dichotomous or finer graded predicate. In accord with German social law we advocate for the binary form. Further discussions focused on multifactorial MedN-configurations, the range of the term, and the variability of evidence requirements. CONCLUSIONS: No matter how the content of MedN is conceptualised, it seems impossible to include its criteria in an algorithm. So deliberative effort is indispensable at any stage of developing a programme to classify medical methods as medically necessary.

[Medical Methods: What Makes them Medically Necessary? Part II: Further Criteria, Overuse, Moving Thresholds, and Grey Zones]. / Medizinische Behandlungsmethoden: Was macht sie medizinisch notwendig? Teil II: Weitere Kriterien, Übermaßverbot, wandernde Grenzen und Grauzonen.

OBJECTIVES: "Medical necessity" (MedN) is a fuzzy term. Our project aims at concretising the concept between medical ethics, social law, and social medicine to support health care regulation, primarily within Germany's statutory health insurance system. In Part I, we identified efficacy, (net)benefit, and the corresponding bodies of evidence as obligatory criteria of MedN. This is the second part suggesting and discussing further criteria. METHODS: See Part I RESULTS: (Part II): As further MedN-criteria we critically assessed a method's effectiveness and acceptance in routine care, its potential beneficiaries, theoretical fundament, cost, and being without alternative as well as patients' self-responsibility, cooperation, and preferences. Since MedN has both lower and upper bounds, we had to consider certain cases of mis- and overuse, due for instance to "indication creep" or "disease mongering". CONCLUSIONS: The additional criteria neither establish MedN (when met singly or together) nor exclude it (when not met). If MedN is rejected in view of the 3 obligatory criteria then further information does not overturn the verdict. If a method is already assessed as being medn then further criteria do not make it "more or less necessary". Though we advocated for a binary MedN-concept (Part I) we are nonetheless convinced that not all medical methods deemed medn are equally medically relevant. Respective differences within the range of MedN could be assessed by techniques to prioritise medical conditions, methods, and aims.

In Situ X-ray Diffraction Study of the Thermal Decomposition of Selenogallates Cs2[Ga2(Se2)2- xSe2+ x] ( x = 0, 1, 2).

The selenogallates CsGaSe3 and Cs2Ga2Se5 release gaseous selenium upon heating. An in situ high-temperature X-ray powder diffraction analysis revealed a two-step degradation process from CsGaSe3 to Cs2Ga2Se5 and finally to CsGaSe2. During each step, one Se22- unit of the anionic chains in Cs2[Ga2(Se2)2- xSe2+ x] ( x = 0, 1, 2) decomposes, and one equivalent of selenium is released. This thermal decomposition can be reverted by simple addition of elemental selenium and subsequent annealing of the samples below the decomposition temperature. The influence of the diselenide units in the anionic selenogallate chains on the optical properties and electronic structures was further studied by UV/vis diffuse reflectance spectroscopy and relativistic density functional theory calculations, revealing increasing optical band gaps with decreasing Se22- content.

Unnecessary abdominal interventions in patients with hereditary angioedema.

BACKGROUND: Hereditary angioedema (HAE) is a rare genetic disorder that leads to recurrent development of mucosal and dermal swelling. It is mediated by bradykinin, and can affect virtually any part of the human body, including the gastrointestinal tract, the extremities, and the laryngeal and pharyngeal regions. Safe and potent drugs are available for acute and prophylactic treatment of HAE. Owing to its unspecific symptoms and unique manifestations, HAE is often misdiagnosed and treated incorrectly. Abdominal edema in particular can resemble appendicitis or cholecystitis, and is therefore often treated with unnecessary surgical procedures. We performed a questionnaire study to quantify this issue. PATIENTS AND METHODS: We designed questionnaires for HAE patients and probands without HAE. The patient-control ratio was chosen at 1 : 2. RESULTS: Compared with the general population, HAE patients are subject to a significantly greater number of invasive diagnostic and therapeutic interventions. Our study showed that the HAE patients were 2.5 times more likely to undergo abdominal surgery (including gynecological and urological procedures) than the individuals without HAE (p = 0.007). The number of operations per patient correlated with the period (number of years) between the onset of symptoms and diagnosis (correlation coefficient 0.511; Spearman). Furthermore, twice as many appendectomies were performed on HAE patients (18.9 % vs. 37.7 %). Our results also showed that the HAE patients were 2.3 times more likely to undergo a gastroscopy than the control group without HAE (p = 0.003). CONCLUSIONS: Patients with rare diseases such as HAE not only suffer from the effects of the disease itself. The conditions are often misdiagnosed for years owing to the general lack of knowledge about such diseases and unspecific manifestations. This leads not only to erroneous and ineffective treatment, but also to needless invasive diagnostic and therapeutic medical procedures. It is therefore important to increase the general knowledge and awareness of orphan diseases such as HAE with a view to improving diagnosis and treatment, minimizing the patients' suffering and enhancing their quality of life.

[Placebo Nocebo Ethics in Communicating with Patients How Anaesthesiologists Should Handle the Psychosomatic Dimension of Briefing]. / Placebo-Nocebo-Ethik für die Patientenkommunikation.

The briefing of patients is part of the daily routine of clinical anaesthesiologists and a central element for justification of medical treatment. It is increasingly apparent that such conversations can significantly affect the success of treatment by eliciting placebo and nocebo effects. Placebo effects are psychosocially caused clinical improvements, mediated by neurobiological mechanisms, which would be omitted in the case of hidden application. Nocebo effects are deteriorations, caused by the same mechanism. Anesthesiologists can make use of the knowledge about placebo and nocebo effects to increase positive impact on the outcome of treatment and to reduce negative effects at the same time. To do so legitimately, physicians have to balance the respect for patients' autonomy, the benevolence, and the non-maleficence for their patients. Patient's autonomy remains the supreme principle of the briefing about treatment and is institutionalized by the informed consent paradigm. Positive and negative expectations are to be handled by patient-oriented communication, but hard paternalistic deceptions and omissions are ethically unjustifiable. We will examine the practical strategies that could be used to deal with the imminent conflict between profound information and optimising placebo and nocebo responses. One key stone of these strategies is the pilot model. It helps to shape briefings as individually required and to promote the wellbeing and autonomy of our patients at the very same time.