[The elective planetary health: Climate, environment and health at the faculty of medicine in Würzburg: Concept, didactic methods and evaluation results]

BACKGROUND

The connections between climate, environment, and health as well as the concept of planetary health need to be integrated into the education of health professionals, as is increasingly demanded both internationally and nationally. Planetary health education should also aim to foster transformative action for climate protection and sustainability. In recent years, innovative teaching formats and objective catalogues have emerged internationally. In Germany, these topics have not yet been integrated into medical education everywhere. Since 2021, the Faculty of Medicine in Würzburg has offered an elective course as a first step of a longitudinal curriculum currently in development. The design, content, structure, and results of the evaluation are discussed in this article and will be used for quality assurance as well as the (further) development of this kind of educational interventions elsewhere.

METHODOLOGY

We developed an elective course for students in their second to tenth semester with 30 onsite and online face-to-face teaching units and an additional project phase. We used an innovative mix of didactic methods with online simulations, training in climate-sensitive health counselling, and interdisciplinary climate communication as well as local sustainability projects in small groups, with a large amount of peer-teaching. A quantitative and qualitative evaluation was done immediately after the teaching units through feedback rounds and online with the evaluation software Evasys®, using closed and open-ended questions exploring learning progress (summer semester) and achievement of learning objectives (winter semester), motivation to participate, acceptance of teaching methods, attitudes, relevance, and further interest. The evaluation questionnaire was slightly modified for the winter semester.

RESULTS

In the summer and winter semester of 2021/2022, a total of 34 students (17 per semester) participated in the elective course; of these, 33 participated in the written evaluation. The evaluation in the summer semester (n = 17) showed a significant increase in self-assessed learning gain, the evaluation in the winter semester (n = 16) indicated a substantial achievement of learning objectives (mean = 3.96 of a 5-point Likert scale). Participants of both semesters (n = 33) regarded peer-teaching as a suitable method (mean = 4.2) and well-implemented (mean = 4.3). The topics were considered highly relevant but not adequately integrated into the main curriculum. There was a high level of interest in local impacts of climate and environmental changes and local measures for climate protection and sustainability. The specific projects in small groups may serve as examples of how transformative action can be promoted in education.

DISCUSSION

In the current dynamic development of the widely demanded integration of planetary health education into curricula, this elective course shows a possible and well-accepted example with a combination of various innovative didactic methods aiming at the levels of knowledge, attitudes, skills, and self-efficacy (or confidence) alike. The positive evaluation by the students and the high interest in local sustainability projects show the potential for future integration into the main curriculum.

CONCLUSION

The elective can serve as an inspiration to tackle the challenge of taking the steps from knowledge to action in planetary health education. While an elective cannot replace the integration of all relevant aspects of planetary health into the main curriculum, it can serve as a space for piloting of future curricular educational interventions and offer opportunities for developing transformative competencies.

Concept and implementation of the longitudinal mosaic curriculum planetary health at the Faculty of Medicine in Würzburg, Germany

Background of the project

Stakeholders in healthcare and science increasingly demand the rapid integration of teaching content on planetary health (PIH) into the curricula of all the healthcare professions. In medical education, such topics are currently only covered inadequately and are mostly limited to elective courses.

Why was the project initiated?

In order to reach all medical students in the sense of a learning spiral and promote an interdisciplinary understanding of planetary health, a longitudinal mosaic curriculum is being developed that introduces aspects of planetary health throughout the entire course of study. We share the first experiences of the start of this project as an example to inspire similar activities elsewhere.

Implementation of the project

We mapped all the courses at the Faculty of Medicine in Würzburg and compared them with existing learning objectives on planetary health topics from the National Competency-Based Catalog of Learning Objectives for Medical Education. We then identified curricular injection points and held consultations with teaching staff and course coordinators from 26 different specialities in order to integrate the respective contents into the courses and, if necessary, develop new content. An overview of all curricular injection points with the corresponding topics, learning objectives, and teaching and examination methods is under development.

Evaluation of the project

The lecturers exchanged ideas with the project team of the teaching clinic of the Faculty of Medicine; further networking meetings to coordinate a learning spiral are to follow. The lecturers were asked to provide structured learning objectives in the categories "knowledge", "attitudes", "skills", and "confidence" on the topics integrated into the courses. Oral as well as written evaluations using Evasys^® questionnaires among students and lecturers are planned.

Final overall assessment outlook

Planetary Health topics have been introduced in several courses following our intervention. In the context of a learning spiral, teaching staff from further medical disciplines will be contacted so that more perspectives can be highlighted at different points in the curriculum. In addition, interdisciplinary teaching formats will be developed in order to take the complexity of the interrelationships into account.

Initiatives promoting planetary health education in Germany: An overview

Planetary health education focuses on the climate and ecological crises and their adverse health effects. Given the acceleration of these crises, nationwide integration of planetary health education into undergraduate and graduate education, postgraduate training and continuing education for all health professionals has repeatedly been called for. Since 2019, planetary health education has been promoted by several national initiatives in Germany that are summarized in this commentary: 1. National Working Group Planetary Health Education, 2. Manual for planetary health education, 3. Catalog of National Planetary Health Learning Objectives in the National Competency-Based Catalog of Learning Objectives for Medical Education, 4. Working Group Climate, Environment and Health Impact Assessment at the Institute for Medical and Pharmaceutical Examinations, 5. Planetary Health Report Card, and 6. PlanetMedEd study: planetary health education in medical schools in Germany. We hope these initiatives promote collaboration across institutions involved in educating and training health professionals, inter-professional cooperation as well as rapid implementation of planetary health education.

Facilitators and barriers to centre- and home-based exercise training in breast cancer patients - a swiss tertiary centre experience

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swiss Cancer Research

Background

Exercise is an effective therapy for cancer patients to reduce fatigue and to improve health-related quality of life and physical function. Yet, cancer patients often do not meet physical activity guidelines.

Purpose

To understand why recommendations are not met, we aimed at identifying facilitators and barriers to supervised, centre-based exercise within a cardio-oncologic rehabilitation (CORE) programme and to unsupervised, home-based exercise as well as strategies used to manage these barriers.

Methods

Breast cancer patients who had completed a CORE programme at a Swiss tertiary centre were recruited. Semi-structured interviews were conducted with subsequent thematic analysis.

Results

Of 37 eligible breast cancer patients, 19 patients (mean age 48.9±9.7 years) participated to our invitation. Facilitators for centre-based exercise were social support, committedness and provision of structured exercise. Barriers towards centre-based exercise included physical and environmental barriers, while psychological barriers were reported predominantly for home-based exercise. Strategies to manage barriers included the adaptation of training circumstances, behaviour change strategies and strategies to deal with side effects.

Conclusions

Our results support the importance of providing CORE programmes and suggest that a special focus should be directed at the transition from supervised to self-organized exercise in order to enhance long-term exercise participation.

BaSAlt - A mixed-methods study protocol on setting-based physical activity promotion and counseling in nursing homes

Introduction

Physical activity (PA) is a major contributor to healthy aging. However, physical inactivity is prevalent among the elderly in Germany, particularly in institutionalized settings such as nursing homes. This paper aims to describe the study objectives, design, methods, assessment types, collection schedules and considerations for analyzing the data within the BaSAlt study on facilitators and barriers for PA promotion in nursing homes.

Methods

We designed the BaSAlt study as a participatory intervention study with multiple measurement points in six to eight nursing homes with a total of approx. 200 residents using four main modules: (1) setting-level analysis of physical activity patterns, physical activity-related climate and physical activity-related interaction with ‘significant others,’ and organizational facilitators and barriers to physical activity, (2) physical-activity related individual-level analysis of objective and self-reported physical activity and sedentary behavior, a geriatric assessment with established procedures, assessment of people's activity and health biographies (biographical mapping) as well as their motivational, subjective well-being and distress status, and (3) a counseling module that integrates counseling at the setting level as well as individual physical activity counseling for residents. In module (4) evaluation, the effects of integrated counseling with regard to the implementation of PA promotion strategies are analyzed.

Discussion

This study will extend our knowledge of physical activity promotion in German nursing homes. Its findings will inform governmental authorities, care professionals, and academics on how to reach a particular group, characterized by inactivity, multimorbidity, and a high prevalence of dementia, residing in nursing homes, a setting that will gain further relevance in the future.

P2614Comparison of global longitudinal strain and ejection fraction in correlation to NT-proBNP in ischemic and non-ischemic heart failure

Background

In chronic heart failure (CHF) NT-proBNP and left ventricular ejection fraction (LVEF) by echocardiography are standard diagnostic as well as follow-up markers and are known to correlate with prognosis. Speckle-tracking echocardiography is a more recent technique to quantify myocardial deformation as a measurement of left ventricular function with potential benefits over LVEF.

Purpose

The purpose of this investigation was to analyse the cross-sectional relationship between 2D speckle tracking-derived global longitudinal strain (GLS) and NT-proBNP plasma levels in a prospective cohort of ischemic and non-ischemic CHF patients.

Methods

We enrolled 205 patients with chronic heart failure. Major inclusion criteria were age over 18 years, stable disease with absence of unplanned hospitalization or change in medication or device therapy in the previous month or major surgery in the previous 3 months. CHF treatment had to be according to the recommendations of the ESC CHF guidelines 2016 and LVEF had to be below 50%.

Patient history, physical examination and an extensive echocardiography exam were performed. Lab results included NT-proBNP. Manual longitudinal strain was calculated using EchoPAC (General Electric Medical Systems, Horten, Norway) by a single and blinded examiner. LVEF was measured using Simpson's biplane method.

Results

205 patients included in the study. The baseline characteristics included mean age 65.0 years and 75% male. Mean GLS was −9.6% (SD ±4.5%) and median NT-proBNP 1269.5 (IQR 379.5–2759.5) ng/ml. The CHF aetiology was 70.0% ischemic vs 30.0% non-ischemic.

There was a significant negative correlation between GLS and NT-proBNP (Pearson r=0.239, p=0.029), this was not significant for LVEF and NT-proBNP (Pearson r=0.149, p=0.228).In a multivariate regression analysis adjusted for age, sex, NYHA classification and HF aetiology, GLS remained significantly correlated with NT-proBNP (adjusted beta-coefficient= 0.289, p=0.011). Furthermore, in contrast to LVEF, GLS showed a significant correlation to NT-proBNP in patients with ischemic (Pearson r=0.266, p=0.049) as well as non-ischemic aetiology of heart failure (Pearson r=0.434, p=0.034).

Conclusion

Global longitudinal strain, not LVEF, was significantly correlated with NT-proBNP in patients with CHF, independently of age, sex, symptoms or heart failure aetiology. This shows that speckle-tracking might be superior to LVEF for the assessment of left ventricular function in CHF.

Effects of Vitamin D3 on asymmetric- and symmetric dimethylarginine in arterial hypertension

BACKGROUND AND AIMS

Accumulating evidence has proposed a correlation between vitamin D (25(OH)D) insufficiency and cardiovascular (CV) disease. Vitamin D associated effects on endothelial function have been suggested to be a possible culprit. The present study investigated the association of vitamin D3 treatment on markers of endothelial dysfunction in patients with arterial hypertension.

METHODS AND RESULTS

The Styrian Vitamin D Hypertension Trial is a double-blind, placebo-controlled, single-centre study conducted at the Medical University of Graz, Austria. A total of 200 study participants with arterial hypertension and 25(OH)D levels below 30ng/mL were enrolled. The study participants were randomized to receive 2800 IU of vitamin D3 per day as oily drops (n=100) or placebo (n=100) for a duration of eight weeks. The present study uses an analysis of covariance (ANCOVA) to investigate the effect of vitamin D3 treatment on symmetric (SDMA) and asymmetric dimethylarginine (ADMA). A total of 187 participants (mean [SD] age 60.0 [11.3] years; 47% women; 25(OH)D 21.2 [5.6]ng/mL; mean systolic blood pressure of 131.4 [8.9] mmHg on a median of 2 antihypertensive drugs) completed the trial. Mean treatment effect was -0.004 (95%CI [-0.03 to 0.04]; P=0.819) on ADMA and 0.001 (95%CI [-0.05 to 0.05]; P=0.850) on SDMA. In the subgroup analysis patients with a 25(OH)D concentration <20ng/mL had a significant increase in their log l-arginine/ADMA ratio (mean treatment effect 18.4 95%CI [1.84-34.9]μmol/L/μmol/L; P=0.030). ClinicalTrials.gov Identifier: NCT02136771 EudraCT number: 2009-018125-70 CONCLUSIONS: Vitamin D3 supplementation in hypertensive patients with low 25-hydroxyvitamin D has no significant effect on ADMA and SDMA.

Effects of maternal high-fat diet and sedentary lifestyle on susceptibility of adult offspring to ozone exposure in rats

Epidemiological and experimental data suggest that obesity exacerbates the health effects of air pollutants such as ozone (O₃). Maternal inactivity and calorically rich diets lead to offspring that show signs of obesity. Exacerbated O₃ susceptibility of offspring could thus be manifested by maternal obesity. Thirty-day-old female Long-Evans rats were fed a control (CD) or high-fat (HF) (60% calories) diet for 6 wks and then bred. GD1 rats were then housed with a running wheel (RW) or without a wheel (SED) until parturition, creating four groups of offspring: CD-SED, CD-RW, HF-SED and HF-RW. HF diet was terminated at PND 35 and all offspring were placed on CD. Body weight and %fat of dams were greatest in order; HF-SED > HF-RW > CD-SED > CD-RW. Adult offspring were exposed to O₃ for two consecutive days (0.8 ppm, 4 h/day). Glucose tolerance tests (GTT), ventilatory parameters (plethysmography), and bronchoalveolar fluid (BALF) cell counts and protein biomarkers were performed to assess response to O₃. Exercise and diet altered body weight and %fat of young offspring. GTT, ventilation and BALF cell counts were exacerbated by O₃ with responses markedly exacerbated in males. HF diet and O₃ led to significant exacerbation of several BALF parameters: total cell count, neutrophils and lymphocytes were increased in male HF-SED versus CD-SED. Males were hyperglycemic after O₃ exposure and exhibited exacerbated GTT responses. Ventilatory dysfunction was also exacerbated in males. Maternal exercise had minimal effects on O₃ response. The results of this exploratory study suggest a link between maternal obesity and susceptibility to O₃ in their adult offspring in a sex-specific manner.

Photoinactivation of Legionella Rubrilucens by Visible Light

In this study, the photoinactivation of Legionella by visible light is investigated. The success of this approach would offer new prospects for technical water disinfection and maybe even for therapeutic measures in cases of Legionella infections. Therefore, Legionella rubrilucens was dispensed on buffered charcoal yeast extract medium agar plates and illuminated with different doses of violet light generated by 405 nm light-emitting diodes (LEDs). A strong photoinactivation effect was observed. A dose of 125 J/ cm² reduced the bacterial concentration by more than 5 orders of magnitude compared to Legionella on unirradiated agar plates. The necessary dose for a one log-level reduction was about 24 J/cm². These results were obtained for extracellular L. rubrilucens, but other Legionella species may exhibit a similar behavior.

Effects of vitamin D supplementation on glycated haemoglobin and fasting glucose levels in hypertensive patients: a randomized controlled trial

AIM

To investigate the efficacy of vitamin D supplementation on glycaemic control.

METHODS

The Styrian Vitamin D Hypertension Trial was a single-centre, double-blind, placebo-controlled study conducted between 2011 and 2014 at the Medical University of Graz, Austria. We enrolled 200 people with arterial hypertension and 25-hydroxyvitamin D [25(OH)D] concentrations <30 ng/mL. Study participants were randomized to receive either 2800 IU of vitamin D or placebo per day for 8 weeks. The present study was a post hoc analysis that incorporated an analysis of covariance (ancova) approach, while adjusting for baseline differences.

RESULTS

A total of 185 participants [mean ± standard deviation age, 60.1 ± 11.3 years; 47% women; mean 25(OH)D 21.2 ± 5.6 ng/mL, mean glycated haemoglobin (HbA1c) 44.8 ± 11.8 mmol/mol and mean body mass index 30.4 ± 5.4 kg/m(2) ] completed the trial. ancova showed a mean treatment effect [95% confidence interval (CI)] on HbA1c of -3.52 (-6.7 to -0.34) mmol/mol (p = .045). There was no difference in fasting glucose -4.7 mg/dL (95% CI -16.3 to 6.9; p = .426).

CONCLUSIONS

Vitamin D supplementation in obese hypertensive patients with low 25(OH)D reduces HbA1c levels. This finding warrants further investigation into potential vitamin D effects on glucose homeostasis.

Resolving the Extragalactic γ-Ray Background above 50 GeV with the Fermi Large Area Telescope

The Fermi Large Area Telescope (LAT) Collaboration has recently released a catalog of 360 sources detected above 50 GeV (2FHL). This catalog was obtained using 80 months of data re-processed with Pass 8, the newest event-level analysis, which significantly improves the acceptance and angular resolution of the instrument. Most of the 2FHL sources at high Galactic latitude are blazars. Using detailed Monte Carlo simulations, we measure, for the first time, the source count distribution, dN/dS, of extragalactic γ-ray sources at E>50  GeV and find that it is compatible with a Euclidean distribution down to the lowest measured source flux in the 2FHL (∼8×10^{-12}  ph cm^{-2} s^{-1}). We employ a one-point photon fluctuation analysis to constrain the behavior of dN/dS below the source detection threshold. Overall, the source count distribution is constrained over three decades in flux and found compatible with a broken power law with a break flux, S_{b}, in the range [8×10^{-12},1.5×10^{-11}]  ph cm^{-2} s^{-1} and power-law indices below and above the break of α_{2}∈[1.60,1.75] and α_{1}=2.49±0.12, respectively. Integration of dN/dS shows that point sources account for at least 86_{-14}^{+16}% of the total extragalactic γ-ray background. The simple form of the derived source count distribution is consistent with a single population (i.e., blazars) dominating the source counts to the minimum flux explored by this analysis. We estimate the density of sources detectable in blind surveys that will be performed in the coming years by the Cherenkov Telescope Array.

Imaging of single cell responses to ER stress indicates that the relative dynamics of IRE1/XBP1 and PERK/ATF4 signalling rather than a switch between signalling branches determine cell survival

An accumulation of misfolded proteins in the endoplasmic reticulum (ER) triggers the unfolded protein response (UPR) mediated via the activation of three transmembrane proteins IRE1, PERK and ATF6. Signalling through these proteins is aimed at enhancing the ER folding capacity and reducing the folding load. If these processes fail to re-establish protein homeostasis within the ER, then cell death prevails via apoptosis. How the shift from pro-survival to pro-apoptotic signalling is regulated remains unclear with both IRE1 and PERK signalling associated with pro-survival as well as pro-apoptotic signalling. To investigate the temporal activation of IRE1 and PERK in live cells and their relationship to cellular fate, we devised single cell reporters for both ER stress signalling branches. SH-SY5Y neural cells stably expressing these fluorescent protein reporter constructs to monitor IRE1-splicing activity and PERK-mediated ATF4-translation were imaged using single cell and high content time lapse live cell microscopy. We could correlate an early onset and attenuation of XBP1 splicing in the IRE1-reporter cells as cytoprotective. Indeed, silencing of IRE1 expression using shRNA inhibited splicing of XBP1 resulting in an early onset of cell death. In contrast, in the PERK-reporter cells, we observed that a slow rate of ATF4-translation and late re-initiation of general translation coincided with cells which were resistant to ER stress-induced cell death. Interestingly, whereas silencing of PERK did not affect overall levels of cell death in response to ER stress, it did increase sensitivity to ER stressors at early time points following treatment. Our results suggest that apoptosis activation in response to ER stress is not caused by a preferential activation of a single UPR branch, or by a switch from one branch to the other. Rather, our data indicated that the relative timing of IRE1 and PERK signalling determines the shift from cell survival to apoptosis.

Are there sex differences in placebo analgesia during visceral pain processing? A fMRI study in healthy subjects

BACKGROUND

We explored sex differences in the neural mechanisms mediating placebo analgesia in an established visceral pain model involving painful rectal distensions in healthy volunteers.

METHODS

N = 15 men and N = 15 women underwent three consecutive functional magnetic resonance imaging sessions during which cued painful rectal distensions were delivered. After an adaptation session, positive expectations were induced with deceptive instructions regarding administration of an analgesic drug (placebo session). In the other session (control), truthful information about an inert substance was given. Sex differences in placebo-induced modulation of neural activation during anticipation and pain were analyzed along with ratings of expected and perceived pain intensity.

KEY RESULTS

Placebo-induced reductions in pain ratings were comparable between men and women. At the level of the brain, group comparisons with respect to differences between the placebo and control conditions revealed greater modulation of the posterior insula (regions-of-interest analysis: pFWE < 0.05) and dorsolateral prefrontal cortex (whole-brain analysis: p < 0.001, uncorrected) during pain anticipation in women. During pain, placebo-induced down-regulation of the insula was altered in women compared to men (ROI analysis: pFWE < 0.05).

CONCLUSIONS & INFERENCES

Our data provide first evidence supporting sex differences in pain-induced neural modulation during visceral placebo analgesia despite similar placebo-induced reductions in perceived pain intensity. These preliminary findings might contribute to elucidating mechanisms mediating placebo effects in clinical conditions associated with chronic abdominal pain such as in irritable bowel syndrome.

Aldosterone to active Renin ratio as screening test for primary aldosteronism: reproducibility and influence of orthostasis and salt loading

Measurement of the aldosterone to active renin ratio (AARR) is the recommended screening test for primary aldosteronism (PA), but several sampling conditions impact on the AARR. We aimed to evaluate the reproducibility and the influence of orthostasis and salt loading on the AARR. The Graz Endocrine Causes of Hypertension (GECOH) study is a diagnostic accuracy study among hypertensive patients at a tertiary care centre in Graz, Austria. With a median interval of 4 weeks we determined the AARR under standardized sampling conditions twice in the sitting position, after 1h in the supine position, and after a salt infusion test (SIT). We identified 9 patients with PA and 151 patients with essential hypertension (EH). The Pearson correlation coefficient between both AARR measurements in the sitting position was 0.79 (p<0.001). In EH, recumbency was associated with a significant decrease of aldosterone and, to a lesser extent, of renin, thus lowering the AARR as compared to the sitting position (p<0.001 for all). In PA, recumbency had only minor effects, but it increased the rate of false negative AARR. SIT suppressed the AARR and its components in EH, whereas in PA only renin was slightly decreased. AARR has a good intra-individual reproducibility and decreases during recumbency. These results suggest that a single AARR determination in the sitting position is a reliable screening tool for PA.

Identification of circulating microRNAs in HNF1A-MODY carriers

AIMS/HYPOTHESIS

HNF1A-MODY is a monogenic form of diabetes caused by mutations in the HNF1A gene. Here we identify, for the first time, HNF1A-MODY-associated microRNAs (miRNAs) that can be detected in the serum of HNF1A-MODY carriers.

METHODS

An miRNA array was carried out in rat INS-1 insulinoma cells inducibly expressing the common human Pro291fsinsC-HNF1A frame shift mutation. Differentially expressed miRNAs were validated by quantitative real-time PCR. Expression of miRNAs in the serum of HNF1A-MODY carriers (n = 31), MODY-negative family members (n = 10) and individuals with type 2 diabetes mellitus (n = 17) was quantified by absolute real-time PCR analysis.

RESULTS

Inducible expression of Pro291fsinsC-HNF1A in INS-1 cells caused a significant upregulation of three miRNAs (miR-103, miR-224, miR-292-3p). The differential expression of two miRNAs (miR-103 and miR-224) was validated in vitro. Strongly elevated levels of miR-103 and miR-224 could be detected in the serum of HNF1A-MODY carriers compared with MODY-negative family controls. Serum levels of miR-103 distinguished HNF1A-MODY carriers from HbA1c-matched individuals with type 2 diabetes mellitus.

CONCLUSIONS/INTERPRETATION

Our study demonstrates that the pathophysiology of HNF1A-MODY is associated with the overexpression of miR-103 and miR-224. Furthermore, our study demonstrates that these miRNAs can be readily detected in the serum of HNF1A-MODY carriers.

How positive and negative expectations shape the experience of visceral pain: an experimental pilot study in healthy women

BACKGROUND

In order to elucidate placebo and nocebo effects in visceral pain, we analyzed the effects of positive and negative expectations on rectal pain perception, rectal pain thresholds, state anxiety and cortisol responses in healthy women.

METHODS

Painful rectal distensions were delivered at baseline, following application of an inert substance combined with either positive instructions of pain relief (placebo group, N = 15), negative instructions of pain increase (nocebo group, N = 17), or neutral instructions (control, N = 15). Perceived pain intensity, unpleasantness/aversion and urge-to-defecate, state anxiety and serum cortisol were determined at baseline, immediately following group-specific instructions and on a second study day after the same instructions (test day). Rectal pain thresholds were determined at baseline and on the test day.

KEY RESULTS

Whereas perceived pain intensity was significantly decreased in the placebo group, the nocebo group revealed significantly increased pain intensity ratings, along with significantly greater anticipatory anxiety on the test day (all P < 0.05 vs controls). Cortisol concentrations were significantly increased in the nocebo group following treatment but not on the test day.

CONCLUSIONS & INFERENCES

The experience of abdominal pain can be experimentally increased or decreased by inducing positive or negative expectations. Nocebo effects involve a psychological stress response, characterized by increased anticipatory anxiety. These findings further underscore the role of cognitive and emotional factors in the experience of visceral pain, which has implications for the pathophysiology and treatment of patients with chronic abdominal complaints.

Highly tolerant tunable waveguide polarization rotator scheme

Integrated polarization rotators are known to exhibit stringent fabrication tolerances, which severely handicap their practical application. Here we present a general polarization rotator scheme that enables both the compensation of fabrication errors and wavelength tunability. The scheme is described analytically, and a condition for perfect polarization conversion is established. Simulations of a silicon-on-insulator polarization rotator show polarization extinction ratios in excess of 40  dB even in the presence of large fabrication errors that in a conventional rotator configuration degrade the extinction ratio to below 5  dB. Additionally, wavelength tuning over ±30  nm is shown.

A morphological change in the fungal symbiont Neotyphodium lolii induces dwarfing in its host plant Lolium perenne

The endophytic fungus Neotyphodium lolii forms symbiotic associations with perennial ryegrass (Lolium perenne) and infection is typically described as asymptomatic. Here we describe a naturally occurring New Zealand N. lolii isolate that can induce dwarfing of L. perenne and suppress floral meristem development in the dwarfed plants. Further to this we demonstrate that the observed host dwarfing correlates with a reversible morphological change in the endophyte that appears associated with colony age. Mycelium isolated from normally growing plants had a typical cottony appearance in culture whereas mycelium from dwarfed plants appeared mucoid. Cottony colonies could be induced to turn mucoid after prolonged incubation and seedlings inoculated with this mucoid mycelium formed dwarfed plants. Mucoid colonies on the other hand could be induced to form cottony colonies through additional further incubation and these did not induce dwarfing. The reversibility of colony morphology indicates that the mucoid dwarfing phenotype is not the result of mutation. Ten isolates from other locations in New Zealand could also undergo the reversible morphological changes in culture, induce dwarfing and had the same microsatellite genotype as the original isolate, indicating that a N. lolii genotype with the ability to dwarf host plants is common in New Zealand.

Outbreak of acute gastroenteritis due to a washwater-contaminated water supply, Switzerland, 2008

An operating error in a sewage treatment plant led to severe drinking water contamination in a well-defined district of a suburban municipality of Zurich, Switzerland. Despite the alert issued to the local population on the same day advising people not to consume the contaminated water, cases of acute gastroenteric diseases were subsequently observed. Considerable faecal contamination was detected the day after the incident in water samples taken up to 500 m from the sewage plant. In a retrospective epidemiological study involving 240 persons living in the affected area, 126 cases of acute gastrointestinal illness were documented. The epidemic curve revealed a peak incidence two days after the event. Stool samples from 11 of 20 patients were positive for noroviruses or Campylobacter jejuni. Although these microorganisms were not detected in the contaminated water, the subsequently conducted case-control study among the surveyed population showed that consumption of contaminated drinking water was associated with gastrointestinal illness (odds ratio 29.1; 95% confidence interval: 9.8-86.4; p = 0.001). The study also revealed the very probable time period of infection. We present the dimension and chronology of this outbreak and discuss the reasons for its localised and temporary spread.

The influence of cholesterol on the motility of cochlear outer hair cells and the motor protein prestin

CONCLUSIONS

We provide evidence that cholesterol reduces electromotility in a dose-dependent matter. The data show that cholesterol modulates electromotility mainly by influencing the motor protein prestin, less by affecting the passive membrane properties.

OBJECTIVES

Elevated serum cholesterol is linked to inner ear disorders and may influence hearing by altering membrane properties of outer hair cells (OHCs) and by affecting the motor protein prestin. In this study we wanted to determine whether cholesterol modulates the electromotility of OHCs and if this modulation results from effects on the membrane properties or on the motor protein prestin.

MATERIALS AND METHODS

The motile responses of 12 isolated OHCs were investigated at increasing concentrations of 0, 0.1, and 1 mM extracellular cholesterol using the patch clamp technique and continuous video image analysis. To study effects on prestin, experiments were performed in 12 cells with half activated protein function and concentrations of 0 and 1 mM cholesterol.

RESULTS

Cholesterol at a concentration of 0.1 mM had no effect on motility. A concentration of 1 mM reduced maximal evoked shortening significantly by 29% in the depolarizing and by 9% in the hyperpolarizing direction. Investigating half activated motor proteins, 1 mM cholesterol reduced movements significantly by 18%, elongations decreased nonsignificantly by 5%.

Optional strategies for reduced metabolism in gray mouse lemurs

Among the order of primates, torpor has been described only for the small Malagasy cheirogaleids Microcebus and Cheirogaleus. The nocturnal, gray mouse lemur, Microcebus murinus (approx. 60 g), is capable of entering into and spontaneously arousing from apparently daily torpor during the dry season in response to reduced temperatures and low food and water sources. Mark-recapture studies indicated that this primate species might also hibernate for several weeks, although physiological evidence is lacking. In the present study, we investigated patterns of body temperature in two free-ranging M. murinus during the austral winter using temperature-sensitive data loggers implanted subdermally. One lemur hibernated and remained inactive for 4 weeks. During this time, body temperature followed the ambient temperature passively with a minimum body temperature of 11.5 degrees C, interrupted by irregular arousals to normothermic levels. Under the same conditions, the second individual displayed only short bouts of torpor in the early morning hours but maintained stable normothermic body temperatures throughout its nocturnal activity. Reduction of body temperature was less pronounced in the mouse lemur that utilized short bouts of torpor with a minimum value of 27 degrees C. Despite the small sample size, our findings provide the first physiological confirmation that free-ranging individuals of M. murinus from the humid evergreen littoral rain forest have the option to utilize short torpor bouts or hibernation under the same conditions as two alternative energy-conserving physiological solutions to environmental constraints.

Pseudomonas aeruginosa transmission is infrequent in New Zealand cystic fibrosis clinics

Pseudomonas aeruginosa is an important pathogen in cystic fibrosis (CF). Although most patients harbour unique P. aeruginosa isolates, some clinics report patients sharing common strains. The overall importance of person-to-person transmission in P. aeruginosa acquisition and whether routine patient segregation is necessary remains uncertain. The present authors therefore investigated the extent of P. aeruginosa transmission in New Zealand CF clinics. New Zealand's seven major CF centres were assessed, combining epidemiological data with computer-assisted SalI DNA fingerprinting of 496 isolates from 102 patients. One cluster of related isolates was significantly more prevalent in the largest clinic than expected by chance. The seven patients with isolates belonging to this cluster had more contact with each other than the remaining patients attending this centre. No other convincing evidence of transmission was found in any of the other smaller clinics. Three P. aeruginosa strains believed to be transmissible between patients in Australian and British CF clinics are present in New Zealand, but there was no definite evidence they had spread. Pseudomonas aeruginosa transmission is currently infrequent in New Zealand cystic fibrosis clinics. This situation could change rapidly and ongoing surveillance is required. The current results confirm that computer-assisted SalI DNA fingerprinting is ideally suited for such surveillance.

Epigenetic inactivation of secreted Frizzled-related proteins in acute myeloid leukaemia

The Wnt signalling pathway has a key function in stem cell maintenance and differentiation of haematopoietic progenitors. Secreted Frizzled-related protein genes (SFRPs), functioning as Wnt signalling antagonists, have been found to be downregulated by promoter hypermethylation in many tumours. To analyse epigenetic dysregulation of SFRPs in acute myeloid leukaemia (AML), we examined the promoter methylation status of SFRP1, -2, -4 and -5 in AML cell lines by methylation-specific polymerase chain reaction (MSP). Aberrant CpG island methylation was found for all four SFRP genes. By real-time reverse transcription-PCR, corresponding transcriptional silencing for SFRP1 and -2 was demonstrated and treatment of cell lines with 5-aza-2'-deoxycytidine resulted in re-expression. The methylation status of the SFRP genes was analysed in 100 specimens obtained from AML patients at diagnosis. The frequencies of aberrant methylation among the patient samples were 29% for SFRP1, 19% for SFRP2, 0% for SFRP4 and 9% for SFRP5. For SFRP2, a correlation between promoter hypermethylation and transcriptional downregulation was found in primary AML samples. Among AML cases with a favourable karyotype, hypermethylation of SFRP genes was restricted to patients with core binding factor (CBF) leukaemia, and aberrant methylation of the SFRP2 promoter was an adverse risk factor for survival in CBF leukaemia.