University of Fribourg

Conservation measures require accurate estimates of density and abundance and population trend assessments. The bonobo (Panpaniscus) is considered Endangered in the IUCN Red List. This classification assumes that available population data are representative. However, with only 30% of the bonobo’s historic geographical range surveyed, reliable information is needed to assess the species' population status. Here, we use information from 13 surveys conducted between 2002 and 2018 in an area of 42,000 km², representing ~27% of bonobo-suitable habitat: Salonga National Park and its corridor, Democratic Republic of the Congo (DRC). Using 8310 km of reconnaissance and transect walks and 27,045 days of camera trapping, we: (1) provide updated estimates of bonobo population density and distribution (42,000 km²; ~5,000 km² of which, to the best of our knowledge, have not been surveyed before by scientists), (2) assess population trends (15,758 km²; 2002–2008 vs 2012–2018), (3) compare estimates obtained with different methods, and (4) assess the factors driving bonobo density and distribution. Although we detected a non-significant population decline, our study suggests that Salonga is a bonobo stronghold, with a population ranging between 8244 and 18,308 mature individuals (density: 0.31 individuals/km²). Standing crop nest counts returned non-significantly lower density estimates than camera trap distance sampling. Nest count-estimates were higher in areas with Marantaceae understorey and those farther away from rivers, while camera trap-estimates were higher in areas with lower human presence. Regardless of the method, bonobos were rarer in proximity to villages. They occurred more often in areas of dense forest cover and in proximity to ranger posts. Our results point towards a declining bonobo population in Salonga, but do not provide sufficient evidence to confirm this statistically. Consequently, the continued monitoring of the bonobo population and preservation of the integrity of Salonga, considering its biological and cultural heritage, will be crucial in the preservation of this stronghold of wild bonobos.

Background Peripheral levels of brain-derived neurotrophic factor (BDNF) are often used as a biomarker for the rapid plasticity-promoting effects of ketamine, psychedelics, and other psychoplastogens in humans. However, studies analyzing peripheral BDNF after psychoplastogen exposure show mixed results. In this meta-analysis, we aimed to test whether the rapid upregulation of neuroplasticity seen in preclinical studies is detectable using peripheral BDNF in humans. Methods This analysis was pre-registered (PROSPERO ID: CRD42022333096) and funded by the University of Fribourg. We systematically searched PubMed, Web of Science, and PsycINFO to meta-analyze the effects of all available psychoplastogens on peripheral BDNF levels in humans, including ketamine, esketamine, LSD, psilocybin, ayahuasca, DMT, MDMA, scopolamine, and rapastinel. Risk of bias was assessed using Cochrane Risk of Bias Tools. Using meta-regressions and mixed effects models, we additionally analyzed the impact of several potential moderators. Results We included 29 studies and found no evidence that psychoplastogens elevate peripheral BDNF levels in humans (SMD = 0.024, p = 0.64). This result was not affected by drug, dose, blood fraction, participant age, or psychiatric diagnoses. In general, studies with better-controlled designs and fewer missing values reported smaller effect sizes. Later measurement timepoints showed minimally larger effects on BDNF. Conclusion These data suggest that peripheral BDNF levels do not change after psychoplastogen administration in humans. It is possible that peripheral BDNF is not an informative marker of rapid changes in neuroplasticity, or that preclinical findings on psychoplastogens and neuroplasticity may not translate to human subjects. Limitations of this analysis include the reliability and validity of BDNF measurement and low variation in some potential moderators. More precise methods of measuring rapid changes in neuroplasticity, including neuroimaging and stimulation-based methods, are recommended for future studies attempting to translate preclinical findings to humans.

The ToxiLaus study aims at evaluating the impact of environmental toxic species on health and diseases’ onset and development. Specifically, the ubiquitous presence of trace elements (TEs) in the environment urges for a better characterization of their influence on human organism. In its primary phase, the ToxiLaus study focused on measuring the urinary concentrations of 23 TEs in the baseline samples from the CoLaus|PsyCoLaus population-based cohort, using inductively coupled plasma mass spectrometry (ICP-MS). Statistical analyses were carried out on 5866 participants, investigating links between TEs concentrations and smoking status, metabolic syndrome and body mass index (BMI). Smoking status was associated with Cd, Zn, Pb, Mo and Hg (respectively OR = 3.64, 1.42, 1.20, 0.69 and 0.58) while metabolic syndrome was associated with Zn and Cd (OR = 1.81 and 1.24 respectively). Concentrations of Zn, Hg, Co, Ni, Cu, Mo, As, Sn, Tl, Fe where significantly different (p < 0.0001) between BMI groups (Normal, Overweight, Obese). Finally, this study provides an overview of the distribution of trace elements in a cohort large sample of the general population, as well as their main associations with cardiovascular risk factors. Theses relations will be further analysed in subsequent phases of the study. Supplementary Information The online version contains supplementary material available at 10.1038/s41598-024-81544-2.

Inkjet printing technology achieves the precise deposition of liquid-phase materials via the digitally controlled formation of picoliter-sized droplets. Beyond graphical printing, inkjet printing has been employed for the deposition of separated drops on surfaces or the formation of continuous layers, which allows to construct materials gradients or periodic features that provide enhanced functionalities. Here, we explore the use of multinozzle, drop-on-demand piezoelectric inkjet technology for the manufacturing of mechanochromic materials, i.e., materials that change their color or fluorescence in response to mechanical deformation. To accomplish this, suitable polyurethane polymers of differing hardness grades were tested with a range of organic solvents to formulate low-viscosity, inkjet-printable solutions. Following their rhe-ological characterization, two solutions comprising "soft" and "hard" polyurethanes were selected for in-depth study. The solutions were imbibed with a mechanochromic additive to yield fluorescent inks, which were either dropcast onto polymeric substrates or printed to form checkerboard patterns of alternating hardness using a laboratory-built, multimaterial inkjet platform. Fluorescence imaging and spectroscopy were used to identify different hardness grades in the dropcast and printed materials, as well as to monitor the responses of these gradient materials to mechanical deformation. The insights gained in this study are expected to facilitate the development of inkjet-printable, mechanochromic polymer materials for a wide range of applications.

A male patient in his early 60s was referred to the cardiology department for evaluation of a persistent apical ventricular thrombus following a myocardial infarction. Transthoracic echocardiography could not rule out the presence of an apical thrombus, leading to the intravenous administration of the contrast agent sulphur hexafluoride (SonoVue). The patient quickly exhibited signs of anaphylaxis accompanied by haemodynamic shock, resulting in cardiac arrest. He was successfully resuscitated with no significant secondary neurological impairment. According to the European Medicines Agency, anaphylactic reactions to the contrast agent sulphur hexafluoride (SonoVue) occur in approximately 1 in 10 000 cases. To our knowledge, this represents the first case of hypersensitivity to sulphur hexafluoride (SonoVue) confirmed by positive in vitro testing.

Melatonin (MT) (N-acetyl-5-methoxytryptamine) is an indoleamine recognized primarily for its crucial role in regulating sleep through circadian rhythm modulation in humans and animals. Beyond its association with the pineal gland, it is synthesized in various tissues, functioning as a hormone, tissue factor, autocoid, paracoid, and antioxidant, impacting multiple organ systems, including the gut-brain axis. However, the mechanisms of extra-pineal MT production and its role in microbiota-host interactions remain less understood. This review provides a comprehensive overview of MT, including its production, actions sites, metabolic pathways, and implications for human health. The gastrointestinal tract is highlighted as an additional source of MT, with an examination of its effects on the intestinal microbiota. This review explores whether the microbiota contributes to MT in the intestine, its relationship to food intake, and the implications for human health. Due to its impacts on the intestinal microbiota, MT may be a valuable therapeutic agent for various dysbiosis-associated conditions. Moreover, due to its influence on intestinal MT levels, the microbiota may be a possible therapeutic target for treating health disorders related to circadian rhythm dysregulation.

The unicellular parasitic protozoan Trichomonas vaginalis causes trichomoniasis, the most prevalent nonviral sexually transmitted disease globally. T. vaginalis evades host immune responses by producing homologs of host proteins, including cytokines such as macrophage migration inhibitory factor. T. vaginalis macrophage migration inhibitory factor ( Tv MIF) helps to facilitate the survival of T. vaginalis during nutritional stress conditions, increases prostate cell proliferation and invasiveness, and induces inflammation-related cellular pathways, thus mimicking the ability of human MIF to increase inflammation and cell proliferation. The production, crystallization and three structures of N-terminally hexahistidine-tagged Tv MIF reveal a prototypical MIF trimer with a topology similar to that of human homologs (hMIF-1 and hMIF-2). The N-terminal tag obscures the expected pyruvate-binding site. The similarity of Tv MIF to its human homologs can be exploited for structure-based drug discovery.

Purpose Overproduction of the intrinsic chromosomally-encoded AmpC β-lactamase is one of the main mechanisms responsible for broad-spectrum β-lactam resistance in Pseudomonas aeruginosa. Our study aimed to evaluate the in-vitro activity of anti-pseudomonal β-lactam molecules associated with the recently-developed and commercially-available β-lactamase inhibitors, namely avibactam, relebactam and vaborbactam, against P. aeruginosa isolates overproducing their AmpC. Methods MIC values of ceftazidime, cefepime, meropenem, imipenem and ceftolozane with or without β-lactam inhibitor were determined for 50 AmpC-overproducing P. aeruginosa clinical isolates. MIC breakpoints for resistance were retained at 8 mg/L for β-lactams and β-lactam/β-lactamase inhibitor combinations containing ceftazidime, cefepime and meropenem, while 4 mg/L was used for those containing imipenem and ceftolozane. The concentration of all β-lactamases inhibitors was fixed at 4 mg/L, except for vaborbactam (8 mg/L). Results The rates of isolates not being resistant to ceftazidime, cefepime, meropenem, imipenem and ceftolozane were found at 12%, 22%, 34%, 8% and 74%, respectively. When combined with avibactam, those rates increased to 60%, 62%, 60%, 46%, and 80%, respectively. The highest rates were found with relebactam-based combinations, being 76%, 64%, 66%, 76% and 84%, respectively. By contrast, associations with vaborbactam did not lead to significantly increased “non-resistance” rates. Conclusion Our results showed that all combinations including relebactam led to higher “non-resistance” rates against AmpC-overproducing P. aeruginosa clinical isolates. The best activity was achieved by combining ceftolozane and relebactam, that might therefore be considered as an excellent clinical alternative against AmpC overproducers.

We answer the following question: if the occupied (or vacant) set of a planar Poisson Boolean percolation model contains a crossing of an 𝑛×𝑛 square, how wide is this crossing? The answer depends on whether we consider the critical, sub-, or super-critical regime, and is different for the occupied and vacant sets.

Introduction Malleolar fractures are the most common ankle fractures and a major risk factor for ankle osteoarthritis in the long-term. Little is known about modifiable risk factors for a satisfactory outcome. This study aimed to assess the long-term clinical, functional and radiological outcomes in patients after osteosynthesis. Methods In this retrospective single center study, we assessed the difference in patients who underwent surgical intervention for malleolar fractures sustained between 2007 and 2014. The reduction was assessed on the first postoperative radiograph. At follow-up patients completed a questionnaire, including the European Foot and Ankle Society (EFAS) and Short Form-12 (SF-12) scores to evaluate patient-reported outcomes and quality of life. Ankle osteoarthritis was assessed using the Kellgren and Lawrence classification. Results One hundred seventeen patients, 102 with anatomic reduction and 15 with malreduction, were reached at mean follow-up at 11.4 years and 10.9 years. The mean EFAS score was 18,0 for anatomic and 16,1 for nonanatomic reduction and 6.1 and 4.5 for the sport component. The rate of satisfaction with the result was 8.2 in anatomic reduction and 7.5 in the malreduction. There was no significant difference in the SF-12 group between the two groups. Anatomic reduction is a protective facture for a satisfactory outcome in the univariate model with the hazard ratio of 5.94. Conclusion Anatomic reduction is one of the strongest protective factors for satisfactory outcome after malleolar fractures in a follow-up of more than 10 years.

The field of evolutionary and speciation genomics has been revolutionised by the ubiquity and availability of genomic data even for non-model organisms. The capability to sequence long-fragment DNA has particularly spurred trans-national initiatives to generate publicly available chromosome-resolved reference genomes across the Tree of Life. Initiatives such as the Darwin Tree of Life (The Darwin Tree of Life Project Consortium et al. 2022) or the European Genome Atlas (ERGA; Mazzoni, Ciofi, and Waterhouse 2023) enable researchers around the globe to address unresolved questions and pursue novel lines of research. The role of chromosomal rearrangements (CRs) in driving evolution has been a long-standing question in evolutionary biology (Berdan et al. 2023; Dobzhansky and Sturtevant 1938; King 1995; Robertson 1916; Wellenreuther and Bernatchez 2018; White 1978). CRs comprise an array of rearrangements that reorganise the linear sequence of the genome, ranging from local structural variants (SVs) such as inversions or duplications, to large-scale karyological changes, including chromosomal fusions and fissions (Berdan et al. 2023; Lucek et al. 2023). Current genomic data have already highlighted that CRs are much more common and diverse across taxa than previously thought (e.g., Damas et al. 2022; Weissensteiner et al. 2020). While CRs can now more easily be mapped within and across taxa, their potential role for evolution and species diversification has often remained enigmatic, and theoretical explorations exist for only a few types of CR (Berdan et al. 2023). At the dawn of broad genome availability for model and non-model organisms alike, our special issue aims to provide a genomic update on the evolutionary impact of various types of CRs. Specifically, our special issue asks what causes the evolution and establishment of CRs and whether these causes differ among taxa? Are CRs randomly distributed across the genome, and do they cause other chromosomal rearrangements? How can CRs promote diversification and how do they potentially lead to speciation? Is the evolutionary impact of CRs the same among different types of CRs? Finally, do CRs have a different evolutionary impact depending on whether autosomes or sex chromosomes are involved?

Richard Wagner's theoretical writings were intended to institute a tradition of interpretation that has had a major impact on the musical world from 1870 to the present day, in Europe and in the United States. In this essay, I concentrate on excerpts concerning conducting and singing practices, highlighting their interrelation in Wagner's view. I then turn to Cosima Wagner's reinterpretation of her late husband's theories and her attempt to codify this Wagnerian tradition of interpretation, contributing to provide a reassessment of the much-debated “Bayreuth style” of performance.

Across diverse ecosystems, bacteria and their hosts engage in complex relationships having negative, neutral, or positive interactions. However, the specific effects of leaf-associated bacterial community functions on plant growth are poorly understood. Although microbes can promote plant growth through various biochemical mechanisms, investigating the community’s functional contributions to plant growth remains to be explored. To address this gap, we characterized the relationships between bacterial community function and host plant growth in the purple pitcher plant ( Sarracenia purpurea ). The main aim of our research was to investigate how different bacterial community functions affect the growth and nutrient content in the plant. Previous research has suggested that microbial communities aid in prey decomposition and subsequent nutrient acquisition in carnivorous plants, including S. purpurea . However, the specific functional roles of bacterial communities in plant growth and nutrient uptake are not well known. In this study, sterile, freshly opened pitchers were inoculated with three functionally distinct, pre-assembled bacterial communities. Bacterial community composition and function were measured over 8 weeks using physiological assays, metagenomics, and metatranscriptomics. Distinct community functions affected plant traits; a bacterial community enriched in decomposition was associated with larger leaves with almost double the biomass of control pitchers. Physiological differences in bacterial communities were supported by metatranscriptomics; for example, the bacterial community with the highest chitinase activity had greater expression of transcripts associated with chitinase enzymes. The relationship between bacterial community function and plant growth observed here indicates potential mechanisms, such as chitinase activity, for host-associated bacterial functions to support pitcher plant growth. IMPORTANCE This study addresses a gap in understanding the relationships between bacterial community function and plant growth. We inoculated sterile, freshly opened pitcher plant leaves with three functionally distinct bacterial communities to uncover potential mechanisms through which bacterial functions support plant health and growth. Our findings demonstrate that distinct community functions significantly influence plant traits, with some bacterial communities supporting more plant growth than in control pitchers. These results highlight the ecological roles of microbial communities in plants and thus ecosystems and suggest that nutrient cycling is an important pathway through which microbes support host plant health. This research provides valuable insights into plant-microbe interactions and the effects of diverse microbial community functions.

The behaviour of mountain glaciers on decadal time scales is a useful indicator for assessing climate change. Although less monitored and studied than the ice sheet, local glaciers and ice caps along the coast of Greenland are substantial contributors to meltwater runoff and sea level rise. This study analyses the cumulative area, ice mass and Equilibrium Line Altitude (ELA) change that occurred on 4100 glaciers and ice caps in West Greenland from 1985 to approximately 2020, using remotely sensed data and including glaciers smaller than 1 km ² in the calculations. The glaciers involved in the study decreased in area by 1774 ± 229 km ² which corresponds to almost −15%. Their surface elevation decreased on average by 20.6 ± 3.9 m, corresponding to a rate of −0.5 ± 0.1 m w.e. a ⁻¹ . The ELA shows a median regional rise of 150 m with marked local variability and higher median rise in the northern part of the study area. Strong regional gradients in ELA of individual glaciers are found, both towards the ice sheet and in areas where local orography affects precipitation. The observed high spatial variability of changes suggests that more monitoring on sub-regional level is needed.

In their study, Stavropoulos et al. (2023) capitalized on supervised machine learning and a longitudinal design and reported that the User-Avatar Bond could be accurately employed to detect Gaming Disorder (GD) risk in a community sample of gamers. The authors suggested that the User-Avatar Bond is a “digital phenotype” that could be used as a diagnostic indicator for GD risk. In this commentary, our objectives are twofold: (1) to underscore the conceptual challenges of employing User-Avatar Bond for conceptualizing and diagnosing GD risk, and (2) to expound upon what we perceive as a misguided application of supervised machine learning techniques by the authors from a methodological standpoint.