Money and trust among strangers

What makes money essential for the functioning of modern society? Through an experiment, we present evidence for the existence of a relevant behavioral dimension in addition to the standard theoretical arguments. Subjects faced repeated opportunities to help an anonymous counterpart who changed over time. Cooperation required trusting that help given to a stranger today would be returned by a stranger in the future. Cooperation levels declined when going from small to large groups of strangers, even if monitoring and payoffs from cooperation were invariant to group size. We then introduced intrinsically worthless tokens. Tokens endogenously became money: subjects took to reward help with a token and to demand a token in exchange for help. Subjects trusted that strangers would return help for a token. Cooperation levels remained stable as the groups grew larger. In all conditions, full cooperation was possible through a social norm of decentralized enforcement, without using tokens. This turned out to be especially demanding in large groups. Lack of trust among strangers thus made money behaviorally essential. To explain these results, we developed an evolutionary model. When behavior in society is heterogeneous, cooperation collapses without tokens. In contrast, the use of tokens makes cooperation evolutionarily stable.     

Economic repercussions of fisheries-induced evolution

Fish stocks experiencing high fishing mortality show a tendency to mature earlier and at a smaller size, which may have a genetic component and therefore long-lasting economic and biological effects. To date, the economic effects of such ecoevolutionary dynamics have not been empirically investigated. Using 70 y of data, we develop a bioeconomic model for Northeast Arctic cod to compare the economic yield in a model in which life-history traits can vary only through phenotypic plasticity with a model in which, in addition, genetic changes can occur. We find that evolutionary changes toward faster growth and earlier maturation occur consistently even if a stock is optimally managed. However, if a stock is managed optimally, the evolutionary changes actually increase economic yield because faster growth and earlier maturation raise the stock’s productivity. The optimal fishing mortality is almost identical for the evolutionary and nonevolutionary model and substantially lower than what it has been historically. Therefore, the costs of ignoring evolution under optimal management regimes are negligible. However, if fishing mortality is as high as it has been historically, evolutionary changes may result in economic losses, but only if the fishery is selecting for medium-sized individuals. Because evolution facilitates growth, the fish are younger and still immature when they are susceptible to getting caught, which outweighs the increase in productivity due to fish spawning at an earlier age.     

Malignant gastric outlet obstruction managed by endoscopic stenting: a prospective single-centre study

Objective. Endoscopic stenting for malignant gastric outlet obstruction was chosen as the primary strategy by which to palliate this complication, which is dominated by weight loss and anorexia. Advanced upper gastrointestinal tract cancers present late and life expectancy is limited. Only smaller multicentre studies point to endoscopic stenting as superior to surgery in terms of clinical outcome and cost. Material and methods. Forty-five consecutive patients with gastric outlet obstruction as a result of advanced upper GI-tract malignancy were enrolled in accordance with the intention-to-treat principle. All patients were offered endoscopic stenting. Oral intake before and after stenting was assessed using the gastric outlet obstruction score system (GOOSS). Various lengths of duodenal Hanaro® self-expanding nitinol stents were delivered through a therapeutic endoscope. Outcome criteria were successful deployment, clinical effect, length of stay in hospital, survival, need for re-intervention and complications. Results. Forty-one patients (91%) were successfully stented. The mean pre-procedure GOOSS improved significantly from 0.39 (95% CI 0.22–0.56) to 2.29 (95% CI 2.01–2.58) after stenting (p<0.0001). Twenty-six patients (63%) improved GOOSS at least one point, whereas 5 patients (12%) did not change GOOSS at all. Mean length of hospital stay was 13 days (95% CI 9–17 days). Mean survival was 121 days (95% CI 62–181 days). Two patients (4%; numbers 6 and 19) sustained perforation without fatalities. Three patients (7%) had stent migration. Procedure-related mortality was zero. Conclusions. Palliative stenting for advanced malignant upper GI-tract tumours at a tertiary Hepato-Pancreato-Biliary Unit is a safe, feasible and effective alternative to surgical bypass with a short hospital stay and prompt improvement of food intake.     

13C-methacetin and 13C-galactose breath tests can assess restricted liver function even in early stages of primary biliary cirrhosis

Objective. The ¹³C-methacetin breath test quantitatively evaluates cytochrome P450-dependent liver function. The ¹³C-galactose breath test non-invasively measures the galactose oxidation capacity of the liver. The aim of this study was to find out whether these breath tests are sensitive parameters also in non-cirrhotic patients with primary biliary cirrhosis.

Material and methods. Nineteen patients with early-stage primary biliary cirrhosis (no cirrhotic alterations in the liver biopsy, Ludwig stage I–III) and 20 healthy controls underwent the ¹³C-methacetin and ¹³C-galactose breath tests.

Results. Patients with primary biliary cirrhosis metabolized less ¹³C-methacetin than controls (cumulative recovery within 30 min 7.5±2.4% versus 14.0±2.6%; p<0.001). When a cut-off?>?9.8% was used for the cumulative recovery after 30 min, the methacetin breath test reached 84.2% sensitivity and 95.0 specificity. In the ¹³C-galactose breath test, the percentage recovery at 60 min in patients was 3.1±1.3%/h, and 6.3±1.1%/h in controls (p<0.001). Using a cut-off?>?4.7%/h, the galactose breath test reached 89.5% sensitivity and 95.0 specificity.

Conclusions. In non-cirrhotic, early-stage, primary biliary cirrhosis the ¹³C-methacetin breath test and the ¹³C-galactose breath test reliably indicate decreased liver function. The ¹³C-galactose breath test can also predict the histological score.     

Pre-clinical studies in cough research: Role of Transient Receptor Potential (TRP) channels

Cough is a protective reflex and defence mechanism in healthy individuals, which helps clear excessive secretions and foreign material from the lungs. Cough often presents as the first and most persistent symptom of many respiratory diseases and some non-respiratory disorders, but can also be idiopathic, and is a common respiratory complaint for which medical attention is sought. Chronic cough of various aetiologies is a regular presentation to specialist respiratory clinics, and is reported as a troublesome symptom by a significant proportion of the population. Despite this, the treatment options for cough are limited. The lack of effective anti-tussives likely stems from our incomplete understanding of how the tussive reflex is mediated. However, research over the last decade has begun to shed some light on the mechanisms which provoke cough, and may ultimately provide us with better anti-tussive therapies. This review will focus on the in vitro and in vivo models that are currently used to further our understanding of the sensory innervation of the respiratory tract, and how these nerves are involved in controlling the cough response. Central to this are the Transient Receptor Potential (TRP) ion channels, a family of polymodal receptors that can be activated by such diverse stimuli as chemicals, temperature, osmotic stress, and mechanical perturbation. These ion channels are thought to be molecular pain integrators and targets for novel analgesic agents for the treatment of various pain disorders but some are also being developed as anti-tussives.     

Effect of Psychosocial Interventions on Quality of Life in Patients With Chronic Heart Failure: A Meta-analysis of Randomized Controlled Trials

BackgroundPatients with chronic heart failure (CHF) usually experience poor quality of life (QoL). Psychosocial interventions tend to affect QoL in CHF. The aim of this study was to explore: 1) the effectiveness of psychosocial interventions on patients' QoL; 2) the magnitude of this effect; and 3) factors that appear to moderate the reported effect on QoL.Methods and ResultsMeta-analysis of the data of 1,074 intervention patients and 1,106 control patients from 16 randomized controlled trials (RCTs) that reported QoL measures in treatment and control groups before and after a psychosocial intervention. Subgroup analyses were conducted between: 1) face-to-face versus telephone interventions; 2) interventions that included only patients versus those that included patients and their caregivers; and 3) interventions conducted by a physician and a nurse only, versus those conducted by a multidisciplinary team. Psychosocial interventions improved QoL of CHF patients (standardized mean difference 0.46, confidence interval [CI] 0.19–0.72; P < .001). Face-to-face interventions showed greater QoL improvement compared with telephone interventions (χ² = 5.73; df = 1; P < .02). Interventions that included caregivers did not appear to be significantly more effective (χ² = 1.12; df = 1; P > .29). A trend was found for multidisciplinary team approaches being more effective compared with nonmultidisciplinary approaches (χ² = 1.96; df = 1; P = .16).ConclusionsA significant overall QoL improvement emerged after conducting psychosocial interventions with CHF patients. Interventions based on a face-to-face approach showed greater benefit for patients' QoL compared with telephone-based approaches. No significant advantage was found for interventions conducted by a multidisciplinary team compared with a physician and nurse approach, or for psychosocial interventions which included patients' caregivers compared with patient-only approaches.     

BCL11B,FLT3, NOTCH1 and FBXW7 mutation status in T-cell acute lymphoblastic leukemia patients

T‐cell acute lymphoblastic leukemia is a heterogeneous malignancy originating from developing lymphocyte precursors likely due to mutations in genes regulating thymocyte differentiation. Here, we characterized mutation status of BCL11B and FLT3 genes, presumably involved in T-ALL, together with FBXW7 and NOTCH1 as known players in T-ALL in 65 pediatric T-cell acute lymphoblastic leukemia patients. We also aimed at the assessment of prognostic value of NOTCH1 and FBXW7 mutations in ALL-IC BFM 2002 protocol.FLT3 and BCL11B mutations were detected in 3% and 2% of patients, respectively. FBXW7 mutations were observed in 8% of patients, while NOTCH1 was mutated in 40%. No correlation was found between NOTCH1 and FBXW7 mutations and traditionally used clinical factors or molecular features. In total we have detected nine mutations, which have not been previously described by others. Eight of them were found in NOTCH1 and one in BCL11B gene.Observed frequencies of NOTCH1 and FBXW7 are in line with previous reports, thus confirming postulated participation of these two genes in T-ALL pathomechanism. Moreover, we report on mutation frequency of FLT3 and BCL11B, not extensively studied in T-ALL so far. Finally, we suggest a putative role of BLC11B as an oncogene in T-ALL pathogenesis.