Is There a "Dead-Anyway" Effect in Willingness to Pay for Risk Reduction?

In einem neueren Beitrag diskutieren Pratt and Zeckhauser (JPE, 1996), welches Maß der marginalen Zahlungsbereitschaft (WTP) von Individuen für die Reduktion ihrer Sterbewahrscheinlichkeit bei öffentlichen Entscheidungen über gefahrenerhebliche Projekte verwendet werden sollte. Sie schlagen vor, die gemessene WTP um den so genannten "Dead-anyway"-Effekt zu berichtigen, der besagt, dass die WTP mit dem Ausgangswert des Risikos zunimmt, dem das befragte Individuum ausgesetzt ist. Dieser Effekt beruht allerdings auf der Abwesenheit vollkommener Märkte für bedingte Güter. Wir diskutieren zunächst die theoretischen Grundlagen des "Dead-anyway"-Effekts und schlagen dann einen neuen empirischen Test mittels der Beziehung zwischen Vermögen, Sterberisiko und Lebenszufriedenheit vor. Eine Anwendung des Tests an Hand zweier Sätze von Umfragedaten aus Deutschland und Australien ergibt keine Bestätigung für den von Pratt und Zeckhauser behaupteten Effekt. In a recent paper, Pratt and Zeckhauser (JPE, 1996) discuss the measure of individuals' willingness to pay (WTP) for the reduction of risks to their lives which should be used for public decisions on risk-reducing projects. They suggest to correct observed WTP for the "dead-anyway" effect, which says that WTP increases with the level of risk to which the individual is exposed - an effect which is due to the imperfection of contingent-claims markets. We first discuss the theoretical foundations of the asserted effect and then propose a new empirical test based on the relationship between wealth, life satisfaction and exposure to risk of dying. Application of the test using two sets of survey data from Germany and Australia.yields no support for the asserted dead-anyway effect.value of statistical life, mortality risk, contingent-claims markets

Influence of molecular temperature on the coherence of fullerenes in a near-field interferometer

We study C70 fullerene matter waves in a Talbot-Lau interferometer as a function of their temperature. While the ideal fringe visibility is observed at moderate molecular temperatures, we find a gradual degradation of the interference contrast if the molecules are heated before entering the interferometer. A method is developed to assess the distribution of the micro-canonical temperatures of the molecules in free flight. This way the heating-dependent reduction of interference contrast can be compared with the predictions of quantum theory. We find that the observed loss of coherence agrees quantitatively with the expected decoherence rate due to the thermal radiation emitted by the hot molecules.Comment: 11 pages, 9 figure

Prognostic relevance of MMP-2 (72-kD collagenase IV) in gastric cancer

The association of MMP-2 (matrix metalloproteinase 2, 72-kD collagenase IV) with invasive and metastatic capacity of tumor cells has implicated a potential role in the prognosis for cancer patients. However, no larger study has been done to prove this hypothesis. The present study was therefore designed to investigate the prognostic impact of MMP-2 in a prospective series of 203 gastric cancer patients. MMP-2 expression was measured immunohistochemically and scored semiquantitatively (score 0-3) in carcinoma cells, and results were correlated with clinicopathological tumor parameters and parameters of the urokinase-type plasminogen activator (uPA) system. Survival analyses were done using the Kaplan-Meier method (log-rank statistics) and multivariate Cox analysis. Significant correlations were found for MMP-2 and Lauren's classification, M stage and proteases/inhibitors of the uPA system in the primary tumor. Kaplan-Meier analysis revealed an association of increasing MMP-2 expression with worse prognosis. This was especially seen in patients with a parallel high expression of uPA receptor. However, differences in survival probabilities between low and high MMP-2 levels were not significant. In a separate analysis of diffuse-type cancers, MMP-2 was significantly associated with disease-free (p = 0.0056) and overall survival (p = 0.0426). Multivariately, MMP-2 was not an independent parameter. Our results demonstrate that there is an association of immunohistochemical detection of MMP-2 with prognosis of cancer patients. For diffuse gastric cancers, it is a significant prognostic parameter, however, not of independent impact. The study further suggests that consideration of interrelated tumor-associated proteases like uPA receptor in combination with MMP-2 may improve its prognostic power

Lower alpha frequency of intraoperative frontal EEG is associated with postoperative delirium: A secondary propensity-matched analysis.

BACKGROUND Postoperative delirium (POD) is a serious complication of surgery, especially in the elderly patient population. It has been proposed that decreasing the amount of anesthetics by titrating to an EEG index will lower POD rate, but clear evidence is missing. A strong age-dependent negative correlation has been reported between the peak oscillatory frequency of alpha waves and end-tidal anesthetic concentration, with older patients generating slower alpha frequencies. We hypothesized, that slower alpha oscillations are associated with a higher rate of POD. METHOD Retrospective analysis of patients` data from a prospective observational study in cardiac surgical patients approved by the Bernese Ethics committee. Frontal EEG was recorded during Isoflurane effect-site concentrations of 0.7 to 0.8 and peak alpha frequency was measured at highest power between 6 and 17 Hz. Delirium was assessed by chart review. Demographic and clinical characteristics were compared between POD and non-POD groups. Selection bias was addressed using nearest neighbor propensity score matching (PSM) for best balance. This incorporated 18 variables, whereas patients with missing variable information or without an alpha oscillation were excluded. RESULT Of the 1072 patients in the original study, 828 were included, 73 with POD, 755 without. PSM allowed 328 patients into the final analysis, 67 with, 261 without POD. Before PSM, 8 variables were significantly different between POD and non-POD groups, none thereafter. Mean peak alpha frequency was significantly lower in the POD in contrast to non-POD group before and after matching (7.9 vs 8.9 Hz, 7.9 vs 8.8 Hz respectively, SD 1.3, p < 0.001). CONCLUSION Intraoperative slower frontal peak alpha frequency is independently associated with POD after cardiac surgery and may be a simple intraoperative neurophysiological marker of a vulnerable brain for POD. Further studies are needed to investigate if there is a causal link between alpha frequency and POD

Association between Serum Thyroid-Stimulating Hormone Levels and Visceral Adipose Tissue: A Population-Based Study in Northeast Germany

Background: Abdominal obesity is a major driver for adverse medical conditions. While an interaction between adipose tissue and thyroid function is thought to exist, to our knowledge, no study has examined the effect of thyroid-stimulating hormone (TSH) on visceral adipose tissue (VAT) in a population-based context. Objective: We determined an association between serum TSH levels and VAT. Methods: A sample of 1,021 female and 956 male adults aged 20-79 years was drawn from registry offices in the cross-sectional, population-based Study of Health in Pomerania Trend (SHIP Trend) in Northeast Germany from 2008 to 2012. Our main exposure was serum TSH levels. Our main outcome was VAT measured using magnetic resonance imaging. The possibly mediating role of leptin on the TSH-VAT association was also assessed. Results: A total of 1,719 participants (87.9%) had serum TSH levels within the reference range. The mean volume of VAT was 5.33 liters for men and 2.83 liters for women. No association between TSH and VAT (β = 0.06, 95% CI: -0.02, 0.14) was observed, and there were no differences detected between sexes. VAT was strongly associated with leptin with a greater effect in women than in men. Leptin was strongly associated with TSH. Conclusions: No association between TSH and VAT was observed. Other biomarkers such as leptin may play a role in the relationship between thyroid function and metabolic risk

The Effect of Perioperative Auditory Stimulation with Music on Procedural Pain: A Narrative Review.

PURPOSE OF REVIEW Music therapy has seen increasing applications in various medical fields over the last decades. In the vast range of possibilities through which music can relieve suffering, there is a risk that-given its efficacy-the physiological underpinnings are too little understood. This review provides evidence-based neurobiological concepts for the use of music in perioperative pain management. RECENT FINDINGS The current neuroscientific literature shows a significant convergence of the pain matrix and neuronal networks of pleasure triggered by music. These functions seem to antagonize each other and can thus be brought to fruition in pain therapy. The encouraging results of fMRI and EEG studies still await full translation of this top-down modulating mechanism into broad clinical practice. We embed the current clinical literature in a neurobiological framework. This involves touching on Bayesian "predictive coding" pain theories in broad strokes and outlining functional units in the nociception and pain matrix. These will help to understand clinical findings in the literature summarized in the second part of the review. There are opportunities for perioperative practitioners, including anesthesiologists treating acute pain and anxiety in emergency and perioperative situations, where music could help bring relieve to patients

Analgesia for the Bayesian Brain: How Predictive Coding Offers Insights Into the Subjectivity of Pain.

PURPOSE OF REVIEW In order to better treat pain, we must understand its architecture and pathways. Many modulatory approaches of pain management strategies are only poorly understood. This review aims to provide a theoretical framework of pain perception and modulation in order to assist in clinical understanding and research of analgesia and anesthesia. RECENT FINDINGS Limitations of traditional models for pain have driven the application of new data analysis models. The Bayesian principle of predictive coding has found increasing application in neuroscientific research, providing a promising theoretical background for the principles of consciousness and perception. It can be applied to the subjective perception of pain. Pain perception can be viewed as a continuous hierarchical process of bottom-up sensory inputs colliding with top-down modulations and prior experiences, involving multiple cortical and subcortical hubs of the pain matrix. Predictive coding provides a mathematical model for this interplay

In Situ Monitoring of the Catalytic Activity of Cytochrome c Oxidase in a Biomimetic Architecture

AbstractCytochrome c oxidase (CcO) from Paracoccus denitrificans was immobilized in a strict orientation via a his-tag attached to subunit I on a gold film and reconstituted in situ into a protein-tethered bilayer lipid membrane. In this orientation, the cytochrome c (cyt c) binding site is directed away from the electrode pointing to the outer side of the protein-tethered bilayer lipid membrane architecture. The CcO can thus be activated by cyt c under aerobic conditions. Catalytic activity was monitored by impedance spectroscopy, as well as cyclic voltammetry. Cathodic and anodic currents of the CcO with cyt c added to the bulk solution were shown to increase under aerobic compared to anaerobic conditions. Catalytic activity was considered in terms of repeated electrochemical oxidation/reduction of the CcO/cyt c complex in the presence of oxygen. The communication of cyt c bound to the CcO with the electrode is discussed in terms of a hopping mechanism through the redox sites of the enzyme. Simulations supporting this hypothesis are included

Comprehensive metabolic profiling of chronic low-grade inflammation among generally healthy individuals.

BACKGROUND: Inflammation occurs as an immediate protective response of the immune system to a harmful stimulus, whether locally confined or systemic. In contrast, a persisting, i.e., chronic, inflammatory state, even at a low-grade, is a well-known risk factor in the development of common diseases like diabetes or atherosclerosis. In clinical practice, laboratory markers like high-sensitivity C-reactive protein (hsCRP), white blood cell count (WBC), and fibrinogen, are used to reveal inflammatory processes. In order to gain a deeper insight regarding inflammation-related changes in metabolism, the present study assessed the metabolic patterns associated with alterations in inflammatory markers. METHODS: Based on mass spectrometry and nuclear magnetic resonance spectroscopy we determined a comprehensive panel of 613 plasma and 587 urine metabolites among 925 apparently healthy individuals. Associations between inflammatory markers, namely hsCRP, WBC, and fibrinogen, and metabolite levels were tested by linear regression analyses controlling for common confounders. Additionally, we tested for a discriminative signature of an advanced inflammatory state using random forest analysis. RESULTS: HsCRP, WBC, and fibrinogen were significantly associated with 71, 20, and 19 plasma and 22, 3, and 16 urine metabolites, respectively. Identified metabolites were related to the bradykinin system, involved in oxidative stress (e.g., glutamine or pipecolate) or linked to the urea cycle (e.g., ornithine or citrulline). In particular, urine 3'-sialyllactose was found as a novel metabolite related to inflammation. Prediction of an advanced inflammatory state based solely on 10 metabolites was well feasible (median AUC: 0.83). CONCLUSIONS: Comprehensive metabolic profiling confirmed the far-reaching impact of inflammatory processes on human metabolism. The identified metabolites included not only those already described as immune-modulatory but also completely novel patterns. Moreover, the observed alterations provide molecular links to inflammation-associated diseases like diabetes or cardiovascular disorders

N-Acetylmuramic Acid (MurNAc) Auxotrophy of the Oral Pathogen Tannerella forsythia: Characterization of a MurNAc Kinase and Analysis of Its Role in Cell Wall Metabolism

Tannerella forsythia is an anaerobic, Gram-negative oral pathogen that thrives in multispecies gingival biofilms associated with periodontitis. The bacterium is auxotrophic for the commonly essential bacterial cell wall sugar N-acetylmuramic acid (MurNAc) and, thus, strictly depends on an exogenous supply of MurNAc for growth and maintenance of cell morphology. A MurNAc transporter (Tf_MurT; Tanf_08375) and an ortholog of the Escherichia coli etherase MurQ (Tf_MurQ; Tanf_08385) converting MurNAc-6-phosphate to GlcNAc-6-phosphate were recently described for T. forsythia. In between the respective genes on the T. forsythia genome, a putative kinase gene is located. In this study, the putative kinase (Tf_MurK; Tanf_08380) was produced as a recombinant protein and biochemically characterized. Kinetic studies revealed Tf_MurK to be a 6-kinase with stringent substrate specificity for MurNAc exhibiting a 6 × 104 - fold higher catalytic efficiency (kcat/Km) for MurNAc than for N-acetylglucosamine (GlcNAc) with kcat values of 10.5 s−1 and 0.1 s−1 and Km values of 200 µM and 116 mM, respectively. The enzyme kinetic data suggest that Tf_MurK is subject to substrate inhibition (Ki[S] = 4.2 mM). To assess the role of Tf_MurK in the cell wall metabolism of T. forsythia, a kinase deletion mutant (1Tf_murK::erm) was constructed. This mutant accumulated MurNAc intracellularly in the exponential phase, indicating the capability to take up MurNAc, but inability to catabolize MurNAc. In the stationary phase, the MurNAc level was reduced in the mutant, while the level of the peptidoglycan precursor UDP-MurNAc-pentapeptide was highly elevated. Further, according to scanning electron microscopy evidence, the 1Tf_murK::erm mutant was more tolerant toward low MurNAc concentration in the medium (below 0.5 µg/ml) before transition from healthy, rod-shaped to fusiform cells occurred, while the parent strain required > 1 µg/ml MurNAc for optimal growth. These data reveal that T. forsythia readily catabolizes exogenous MurNAc but simultaneously channels a proportion of the sugar into peptidoglycan biosynthesis. Deletion of Tf_murK blocks MurNAc catabolism and allows the direction of MurNAc solely to peptidoglycan biosynthesis, resulting in a growth advantage in MurNAc-depleted medium. This work increases our understanding of the T. forsythia cell wall metabolism and may pave new routes for lead finding in the treatment of periodontitis