Specimen collection is essential for modern science

Natural history museums are vital repositories of specimens, samples and data that inform about the natural world; this Formal Comment revisits a Perspective that advocated for the adoption of compassionate collection practices, querying whether it will ever be possible to completely do away with whole animal specimen collection.

Extremal states and coupling properties in electroelasticity

Electroelastic materials possess properties most attractive for the design of smart devices and systems such as actuators and sensors. Typical polymers show changes in shape under the action of an electric field, and vice versa, together with fast actuation times, high strain levels and low elastic moduli. This paper deals with an Ogden model inspired framework for large deformation electroelasticity which, as a special case, can also be reduced to the modelling of transversely isotropic elasticity. Extremal (local) states are elaborated based on a coaxiality analysis, i.e. extremal states of energy are considered at fixed deformation and changing direction of electric field, respectively, fixed electric field and changing principal directions of deformation. This analysis results in extremal states when stresses and strain commutate, respectively, dielectric displacements and electric field are aligned. In order to further elaborate electromechanical coupling properties, the sensitivity of stresses with respect to electric field is analysed. This sensitivity is represented by a third-order tensor which, in general, depends on deformation and electric field. To illustrate this third-order tensor, a decomposition into deviators is adopted. Related norms of these deviators, together with the electromechanical coupling contribution to the augmented energy, are investigated for different states under homogeneous deformation and changing electric field direction. The analysis is considered to contribute to a better understanding of electromechanical coupling properties and extremal states in large deformation electroelasticity and by that, as a long-term goal, may contribute to the improved design of related smart devices and systems. This article is part of the theme issue 'The Ogden model of rubber mechanics: Fifty years of impact on nonlinear elasticity'.

Early mortality and complications following first-time catheter ablation of atrial fibrillation in a nationwide cohort

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) is the most common clinical arrhythmia. Pulmonary vein isolation (PVI) by catheter ablation has become a cornerstone in the treatment of AF. Serious complications to PVI have been reported to be at an acceptable level and risk of death after AF ablation is low.

Purpose

In a contemporary nationwide cohort of patients undergoing first-time PVI by catheter ablation, we wanted to investigate the 30-day mortality after ablation, and to examine risk and potential risk factors of PVI-related complications.

Methods

Population-based cohort study in patients who underwent first-time PVI by catheter ablation between 2011-2018 identified from the National Danish Ablation Registry. Primary outcome was early post-procedural mortality, defined as death of any cause within 30 days of index PVI procedure, or in connection to a hospitalization started within 30 days. Secondary outcomes were all-cause rehospitalization and complication, including postoperative infection, cardiac, vascular, neurological, vascular, and pulmonary complications within 30 days. Data on mortality and complications were collected from national health and administrative registries. Binary regression was used to estimate risk ratio (RR) with 95% confidence intervals (CI) for association between selected predictors and any complication, and adjusted gender, age, BMI, prior ablation, calendar period (ablation from 2011-2013, 2014-2016, and >2016).

Results

We included 8560 patients. Median age was 62, 66% were men, 12% had a history of heart failure, and median CHA2DS2VASc score was 1 (Interquartile range [IQR]; 1-2). Charlton Comorbidity index (CCI) was none in 66%, moderate in 29% and severe in 5%. A total of 10 (0.12%) patients died within 30 days of ablation, of which 4 patients died during initial hospitalization. Median time to death was 20 (IQR, 12 to 29) days. Patients who died were more likely to have experienced a procedure-related complication (40% vs. 4%, P<0.001). Procedure-related complications occurred in 298 (3.5%), and the risk was 4.4%, 3.0% and 3.3% in the time periods between 2011-2013, 2014-2016 and >2016, respectively. Most common complications were postoperative infection (26%), cardiac complication (26%), and vascular complications (18%). Complication risk was increased in patients with higher age (aRR, 65-74 year; 1.67 [1.32-2.11] and >74 years; 2.48 [1.60-3.84]), moderate CCI (aRR 1.45 [1.14-1.83]), cardiovascular disease (aRR 1.52 [1.09-2.11]) and antithrombotic treatment (aRR 1.41 [1.05-1.89]). After first-time PVI, 1.963 (23%) patients were re-hospitalized within 30 days, and most common primary discharge diagnoses were AF (87%) and direct cardioversion was performed in 765 (39%) patients.

Conclusion

In a nationwide cohort of patients who underwent first-time PVI, number of deaths within 30 days of ablation was low (0.12%). Risk of complication was low and 23% of the patients were re-hospitalized within 30 days.

Engaging men and boys in gender equity programs in humanitarian settings: A scoping review

Background

Engaging men and boys in interventions designed to achieve gender equity has demonstrated positive impact on reducing gender-based violence (GBV) and improving women's and girls' health. This scoping review describes the content of published gender equity programs that engage men/boys in humanitarian settings.

Methods

We searched five databases for peer-reviewed articles of GBV programs implemented with men/boys in humanitarian settings (published between Jan 2000 and Dec 2019). From each article, we extracted information on program evaluation strategies, theoretical frameworks, and modes of adaptation to the humanitarian setting.

Results

Of 21 published articles of GBV programs with men/boys (implemented in 17 countries), the majority utilized a psychosocial (attitudes) or structural (feminism) theory and only seven were not theoretically based. As to evaluation, nine programs employed quantitative methods whilst the rest employed qualitative or mixed methods; outcome evaluation data were gathered from both men only or men and women. In most articles, authors described how they developed the program taking into account the humanitarian setting and incorporated practical delivery components to overcome contextual barriers.

Conclusions

In describing the content of published GBV interventions that include men/boys in humanitarian settings, this scoping review can guide future efforts to improve women's/girls' health. Such programs can help realize SDG5 to “achieve gender equality and empower all women and girls.”

Key messages

Including men in interventions designed to improve women’s/girls’ health in humanitarian settings is critical. A scoping review of the published literature can identify existing knowledge and guide future programs.

Phylogeny and sex chromosome evolution of palaeognathae

Many paleognaths (ratites and tinamous) have a pair of homomorphic ZW sex chromosomes in contrast to the highly differentiated sex chromosomes of most other birds. To understand the evolutionary causes for the different tempos of sex chromosome evolution, we produced female genomes of 12 paleognathous species and reconstructed the phylogeny and the evolutionary history of paleognathous sex chromosomes. We uncovered that Palaeognathae sex chromosomes had undergone stepwise recombination suppression and formed a pattern of "evolutionary strata". Nine of the 15 studied species' sex chromosomes have maintained homologous recombination in their long pseudoautosomal regions extending more than half of the entire chromosome length. We found that in older strata, the W chromosome suffered more serious functional gene loss. Their homologous Z-linked regions, compared with other genomic regions, have produced an excess of species-specific autosomal duplicated genes that evolved female-specific expression, in contrast to their broadly expressed progenitors. We speculate the "defeminization" of Z chromosome with underrepresentation of female-biased genes and slow divergence of sex chromosomes of paleognaths might be related to their distinctive mode of sexual selection targeting females that evolved in their common ancestors.

[Breathing: Ambient Air Pollution and Health - Part III]

The third part of the DGP statement introduces the current body of knowledge on less studied health outcomes associated with exposure to ambient air pollution: the negative impact on metabolism leading to impaired glucose tolerance and diabetes as well as contribution to the development of neurodegenerative disorders and delayed cognitive function in children. Furthermore, prenatal exposure and adverse effects on mother and child are addressed. Finally, the currently discussed biological mechanisms underlying various health effects associated with exposure to air pollution are described.Differing, but often complementary biological mechanisms create the basis for the diverse health outcomes caused by air pollution. Oxidative stress and a subclinical inflammatory response in the lungs and on a systemic level ("low-grade systemic inflammation") are considered to be key mechanisms. They promote secondary alterations in the body, such as vascular or metabolic processes, and may also result in the currently studied epigenetic phenomena or neuroinflammation. In this context, the health significance of soluble particulate matter and the role of ultrafine particles translocated across biological membranes into blood vessel and transported via the circulation to secondary target organs, such as liver, brain or the fetus, are intensively discussed.Diabetes is one of the leading chronic diseases worldwide, with a prevalence of almost 14 % in Germany. Although lifestyle factors are the main causes, current evidence suggests that long-term exposure to air pollution may additionally increase the risk for type 2 diabetes. Supporting evidence for a causal role of air pollution is provided by studies addressing the regulation of the blood glucose levels in metabolically healthy participants, insulin sensitivity, or pregnancy-related diabetes. Experimental studies provide further support for plausible biological mechanisms. However, prospective studies are needed to gain more evidence, taking multiple lifestyle and environmental factors, such as green space and noise, and an improved individual exposure assessment into account.The aging population has an increased risk of neurodegenerative diseases. First studies point towards a contribution of chronic exposure to air pollution, specifically by particulate matter. Several studies report its association with decreased neurocognitive capacity or an increased prevalence of dementia or Alzheimer's disease in adults. However, the studies are inhomogeneous regarding design, exposure and outcome, leading to inconsistent results. With respect to the influence on neurocognitive development of children, first studies suggest an association between the level of air pollution, e. g. at school, and delayed cognitive development.Even though the evidence for the different biological endpoints during pregnancy is still heterogeneous, the studies generally point towards an adverse impact of air pollution on the maternal and fetal organisms. The strongest evidence exists for low birth weight, with small effect sizes of only some grams, and for a higher incidence of reduced birth weight (< 2500 g). An increased risk for gestational hypertension and preeclampsia underscores the possible impact of exposure to air pollution on the maternal organism. However, the current body of evidence does not yet allow a final conclusion on the influence of intrauterine exposure to air pollution regarding early childhood lung function and development of allergies, particularly in light of the fact that it is hard to distinguish in epidemiological studies between the effects of pre- and postnatal exposure.

[Breathing: Ambient Air Pollution and Health - Part II]

The second part of the DGP-statement on adverse health effects of ambient air pollution provides an overview of the current ambient air quality in Germany and its development in the past 20 years. Further, effects of air pollution on the cardiovascular system und underlying pathophysiological mechanisms are introduced. Air pollutants form a highly complex and dynamic system of thousands of organic and inorganic components from natural and anthropogenic sources. The pollutants are produced locally or introduced by long-range transport over hundreds of kilometers and are additionally subjected to local meteorological conditions. According to air quality regulations ambient air quality is monitored under uniform standards including immission of particulate matter, up to 2.5 µm (PM_2.5) or 10 µm (PM₁₀) in aerodynamic diameter, and of nitrogen dioxide (NO₂) or ozone (O₃). The clean air measures of recent years led to a continuous decline of air pollution in the past 20 years in Germany. Accordingly, the focus is nowadays directed at population-related health hazards caused by low concentrations of air pollution. Exceeded limits for sulfur dioxide, carbon monoxide, benzene and lead are not detected anymore. Also the number of days with increased ozone concentration declined, although the annual mean concentration is unaltered. Decreasing concentrations of particulate matter and NO₂ have been observed, however, about 40 % of the monitoring stations at urban traffic sites still measure values exceeding current limits for NO₂. Moreover, the stricter, solely health-based WHO-standards for PM_2.5, PM₁₀ and NO₂ are still not met so that an optimal protection from air pollution-related health hazards is currently not given for the German population. In recent years, the findings of numerous cross-sectional and longitudinal studies underscored adverse effects of air pollution on the cardiovascular system, especially for particulate matter, although the level of evidence still varies for the different health outcomes. Further, the studies show that cardiovascular health hazards on the population level are of higher relevance than those for the respiratory system. The existing evidence for cardiovascular mortality, hospitalization, ischemic heart diseases, myocardial infarction and stroke can be regarded as strong, while that for heart failure is rather moderate. While the evidence for air pollution-related short-term alteration of the cardiac autonomic balance can be considered as sufficient, long-term effects are still unclear. Likewise, the heterogeneous findings on air pollution-related arrhythmia do currently not allow a distinct conclusion in this regard. A large number of studies support the observation that both, short- and long-term air pollution exposure contribute to increased blood pressure, may impair vascular homeostasis, induce endothelial dysfunction and promote the progression of atherosclerotic lesions. These effects provide reasonable biological explanation for the fatal events associated with exposure to air pollution. Short-term exposure may not pose a significant risk on healthy individuals but may be considered as precursor for fatal events in susceptible populations, while repetitive or long-term exposure may contribute to the development of cardiovascular diseases even in healthy subjects.

[Breathing: Ambient Air Pollution and Health - Part I]

Die Exposition gegenüber Luftschadstoffen wird von der Weltgesundheitsorganisation weltweit als eine führende Gesundheitsgefährdung und als der wichtigste umweltbedingte Risikofaktor mit besonders hoher Krankheitslast in Ländern mit niedrigem und mittlerem Einkommen angesehen.

Die Luftschadstoffbelastung besteht aus hochkomplexen Gemischen verschiedenster organischer und anorganischer Bestandteile natürlichen oder anthropogenen Ursprungs, die lokal entstehen oder durch Ferntransport über hunderte von Kilometern regional eingebracht werden können. Zusätzlich wird die Schadstoffkonzentration durch die regionalen, meteorologischen Verhältnisse beeinflusst. Dementsprechend können Schadstoffkonzentration und Zusammensetzung an einem Ort deutlich variieren, zeigen aber typischerweise einen Tages-, Wochen- und Jahresgang.

Mittels gesetzlicher Grenzwerte wie in der „Air Quality Directive“ der Europäischen Union festgelegt, soll eine Gesundheitsgefährdung der Bevölkerung durch die Schadstoffe minimiert werden. Allerdings weichen die Grenzwerte der Europäischen Union von den Empfehlungen der WHO insbesondere für Feinstaub deutlich nach oben ab.

Zur Abschätzung der Luftschadstoffbelastung wird auf einzelne Indikatoren zurückgegriffen, die die partikuläre, wie Feinstaub bis 2,5 µm (PM2.5) bzw. bis 10 µm aerodynamischen Durchmesser (PM10), und die gasförmige Belastung, wie Stickstoffdioxid (NO2) und Ozon (O3), charakterisieren. Für die meisten Luftschadstoffe wurden über die letzten Jahrzehnte in der westlichen Welt abfallende Konzentrationen beobachtet, sodass hier v. a. die Gesundheitsgefährdung bei geringerer Schadstoffbelastung im Vordergrund steht. Insbesondere Ballungsgebiete in Deutschland leiden aber noch unter erhöhter Luftverschmutzung.

Zahlreiche Studien haben in den letzten Jahrzehnten schädliche Auswirkungen von Luftschadstoffen auf die Gesundheit der Bevölkerung belegt. Die Auswirkungen betreffen v. a. den Atemtrakt und das kardiovaskuläre System und reichen von unspezifischen Atemwegs- und kardiovaskulären Symptomen über Beeinträchtigungen der Lungenfunktion, vermehrter Medikamenteneinnahme und akuter Exazerbation von vorbestehenden Lungenerkrankungen, Herzinfarkten und Schlaganfällen bis hin zu Todesfällen. Neuere Studien weisen auf weitere Gesundheitsendpunkte, wie z. B. Atherosklerose, Einschränkungen des fetalen Wachstums, der kognitiven Funktion und neuronalen Entwicklung, Diabetes mellitus sowie auf ein verbessertes Verständnis der zugrundeliegenden pathophysiologischen Mechanismen hin.

In der „Global Burden of Disease Study“ von 2015 wird die Bedeutung der Luftschadstoffbelastung für Mortalität und Morbidität v. a. durch chronische Erkrankungen quantifiziert. Bei der vorzeitigen Mortalität, v. a. aufgrund von kardiovaskulären Todesursachen, lag PM2.5 in der Außenluft weltweit auf Rang 5, unmittelbar hinter den allgemeinen Risikofaktoren erhöhter Blutdruck, Rauchen sowie erhöhte Glukose- und Cholesterinwerte. In Deutschland liegt die Krankheitslast durch Luftverschmutzung an zehnter Stelle der Risikofaktoren und ist damit auch hierzulande der wichtigste umweltbezogene Risikofaktor. Entsprechend zeigen Studien, dass der Einfluss von Luftschadstoffen die Sterblichkeit in Europa erhöht und die mittlere Lebenserwartung um etwa ein Jahr reduzieren kann.

In dem hier vorgestellten Positionspapier fasst die Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin den aktuellen Wissensstand zu den Gesundheitseffekten von Luftschadstoffen zusammen und leitet daraus Empfehlungen für einen umweltbezogenen Gesundheitsschutz ab. Der hier vorgestellte erste Teil fokussiert sich auf allgemeine Grundlagen und die Wirkungen im Atemtrakt.

Changes in cold-related mortalities between 1995 and 2016 in South East England

Objective

The aim of the study was to examine trends in cold-related mortalities between 1995 and 2016.

Study design

This is a longitudinal mortality study.

Methods

For men and women aged 65–74 years or those older than 85 years in South East England, the relationship between daily mortality (deaths per million population) and outdoor temperatures below 18 °C, with allowance for influenza epidemics, was assessed by linear regression on an annual basis. The regression coefficients were expressed as a percentage of the mortality at 18 °C to adjust for changes in mortality through health care. Trends in ‘specific’ cold-related mortalities were then examined over two periods, 1977–1994 and 1995–2016.

Results

In contrast to the early period, annual trends in cold-related specific mortalities showed no decline between 1995 and 2016. ‘Specific’ cold-related mortality of women, but not men, in the age group older than 85 years showed a significant increase over the 1995–2016 period, which was different from the trend over the earlier period (P < 0.01).

Conclusion

Despite state-funded benefits to help alleviate fuel poverty and public health advice, very elderly women appear to be at increasing risk of cold-related mortality—greater help may be necessary.

•

In contrast to 1977-94, a reduction of excess winter mortality from all causes did not take place between 1995 and 2016.

•

Similar trends are seen in mortality from ischaemic heart, cerebrovascular and respiratory diseases.

•

Excess winter mortality from all causes rose over this period in women older than 85 years.

Wartelistenführung und Organvermittlung zur Lungentransplantation 2018 – Aktuelles für den Pneumologen

Die gesetzliche Grundlage der Allokation und Wartelistenführung zur Lungentransplantation wurde 2017 novelliert. Durch die aktuelle Richtlinie ergeben sich für die Transplantationszentren wichtige Änderungen. Wesentliche Neuerungen der Richtlinie betreffen die Transplantationskonferenz, die Indikationen zum Verfahren und die Führung der Warteliste zur Organtransplantation. In bestimmten klinischen Konstellationen ist die Aufnahme von Patienten nun beschränkt, und es gibt neue Regeln zur Größenkompatibilität von Spenderlunge und Empfänger. Zudem wird im Detail beschrieben, wie die Parameter, die dem Lung Allocation Score (LAS) zugrunde liegen, definiert sind inkl. der Durchführung der hierfür notwendigen Untersuchungen. Darüber hinaus gibt der vorliegende Artikel einen Überblick über die Organzuteilung durch die Vermittlungsstelle.

Cluster structures influenced by interaction with a surface

Systematic investigation of how cluster structures change upon interaction with a surface, using global structure optimization by evolutionary algorithms.

[Position Paper: Significance of the Forced Vital Capacity in Idiopathic Pulmonary Fibrosis]

Spirometry is a highly standardized method which allows to measure the forced vital capacity (FVC) with high precision and reproducibility. In patients with IPF FVC is directly linked to the disease process which is characterized by scaring of alveoli and shrinkage of the lungs. Consequently, there is ample evidence form clinical studies that the decline of FVC over time is consistently associated with mortality in IPF. As for the first time effective drugs for the treatment of IPF are available it becomes obvious that in studies which could demonstrate that the drug reduces FVC decline, a numerical effect on mortality was also observed, while in one study where a significant effect on FVC decline was missed, there was also no change in mortality. Based on these studies FVC decline is a validated surrogate of mortality in IPF. It is concluded that FVC decline is not only accepted as an endpoint of clinical treatment trials in IPF but is also valid as a patient related outcome parameter which should be considered for the assessment of the efficacy of an IPF drug.

Introduction of the lung allocation score in Germany

The aim of this study was to assess performance of the new lung allocation system in Germany based on lung allocation score (LAS). Retrospective analysis of waitlist (WL) outflow, lung transplantation (LTx) activity and 3-month outcomes comparing 1-year pre- and post-LAS introduction on December 10, 2011 was performed. Following LAS introduction, WL registrations remained constant, while WL mortality fell by 23% (p = 0.04). Reductions in WL mortality occurred in patients with cystic fibrosis (CF; -52%), emphysema (chronic obstructive pulmonary disease [COPD]; -49%) and pulmonary hypertension (PH; -67%), but not idiopathic pulmonary fibrosis (IPF; +48%). LTx activity increased by 9% (p = 0.146). Compared to pre-LAS, more patients with IPF (32% vs. 29%) and CF (20% vs. 18%) underwent transplantation and comparatively fewer with COPD (30% vs. 39%). Median LAS among transplant recipients was highest in PH (53) and IPF (49) and lowest in COPD (34). Transplantation under invasive respiratory support increased to 13% (in CF 28%, +85%, p = 0.017). Three-month survival remained unchanged (pre: 96.1% and post: 94.9%, p = 0.94). Following LAS implementation in Germany, reductions in waiting list size and WL mortality were observed. Composition of transplant recipients changed, with fewer COPD and more IPF recipients. Transplantation under invasive respiratory support increased. Reductions in WL mortality were most pronounced among CF and PH patients.

Endogenous-peptide-dependent alloreactivity: new scientific insights and clinical implications

T-cell alloreactivity is generated via immune responsiveness directed against allogeneic (allo) human leucocyte antigen (HLA) molecules. Whilst the alloresponse is of extraordinary potency and frequency, it has often been assumed to be less peptide-specific than conventional T-cell reactivity. Recently, several human studies have shown that both alloreactive CD8(+) and CD4(+) T cells exhibit exquisite allo-HLA and endogenous peptide specificity that has also underpinned tissue-specific allorecognition. In this review, we summarize former and recent scientific evidence in support of endogenous peptide (self-peptide)-dependence of T-cell alloreactivity. The clinical implications of these findings will be discussed in the context of both solid organ transplantation and haematopoietic stem cell transplantation (HSCT). Insights into the understanding of the molecular basis of T-cell allorecognition will probably translate into improved allograft survival outcomes, lower frequencies of graft vs host disease and could potentially be exploited for selective graft vs leukaemia effect to improve clinical outcomes following HSCT.

[German guideline for diagnosis and management of idiopathic pulmonary fibrosis]

Idiopathic pulmonary fibrosis is a fatal lung disease with a variable and unpredictable natural history and limited treatment options. Since publication of the ATS-ERS statement on IPF in the year 2000 diagnostic standards have improved and a considerable number of randomized controlled treatment trials have been published necessitating a revision. In the years 2006 - 2010 an international panel of IPF experts produced an evidence-based guideline on diagnosis and treatment of IPF, which was published in 2011. In order to implement this evidence-based guideline into the German Health System a group of German IPF experts translated and commented the international guideline, also including new publications in the field. A consensus conference was held in Bochum on December 3rd 2011 under the protectorate of the "Deutsche Gesellschaft für Pneumologie und Beatmungsmedizin (DGP)" and supervised by the "Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften" (AWMF). Most recommendations of the international guideline were found to be appropriate for the german situation. Based on recent clinical studies "weak negative" treatment recommendations for pirfenidone and anticoagulation were changed into "weak positive" for pirfenidone and "strong negative" for anticoagulation. Based on negative results from the PANTHER-trial the recommendation for the combination therapy of prednisone plus azathiorpine plus N-acetlycsteine was also changed into strong negative für patients with definite IPF. This document summarizes essential parts of the international IPF guideline and the comments and recommendations of the German IPF consensus conference.