Search

The information system PANGAEA provides targeted support for research data management as well as long-term data archiving and publication. PANGAEA is operated as an open access library for archiving, publishing, and distributing georeferenced data from earth and environmental sciences. It focuses on observational and experimental data. Citability, comprehensive metadata descriptions, interoperability of data and metadata, a high degree of structural and semantic harmonization of the data inventory as well as the commitment of the hosting institutions ensures the long-term usability of archived data. PANGAEA is a pioneer of FAIR and open data infrastructures to enable data intensive science and an integral component of national and international science and technology activities. This paper provides an overview of the recent organisational, structural, and technological advancements in developing and operating the information system. [ABSTRACT FROM AUTHOR]

Intestinal microbiota dysbiosis can initiate overgrowth of commensal Candida species – a major predisposing factor for disseminated candidiasis. Commensal bacteria such as Lactobacillus rhamnosus can antagonize Candida albicans pathogenicity. Here, we investigate the interplay between C. albicans, L. rhamnosus, and intestinal epithelial cells by integrating transcriptional and metabolic profiling, and reverse genetics. Untargeted metabolomics and in silico modelling indicate that intestinal epithelial cells foster bacterial growth metabolically, leading to bacterial production of antivirulence compounds. In addition, bacterial growth modifies the metabolic environment, including removal of C. albicans' favoured nutrient sources. This is accompanied by transcriptional and metabolic changes in C. albicans, including altered expression of virulence-related genes. Our results indicate that intestinal colonization with bacteria can antagonize C. albicans by reshaping the metabolic environment, forcing metabolic adaptations that reduce fungal pathogenicity. Commensal bacteria such as Lactobacillus rhamnosus can inhibit the pathogenicity of the fungus Candida albicans. Here, Alonso-Roman et al. investigate the interplay between C. albicans, L. rhamnosus and intestinal epithelial cells, showing that changes in the metabolic environment, induced by the bacteria, trigger adaptations in C. albicans that reduce fungal pathogenicity. [ABSTRACT FROM AUTHOR]

Ultrastructural analysis of autopsy samples from COVID-19 patients usually suffers from significant structural impairment possibly caused by the rather long latency between death of the patient and an appropriate sample fixation. To improve structural preservation of the tissue, we obtained samples from ventilated patients using a trans-bronchial "cryobiopsy" within 30 min after their death and fixed them immediately for electron microscopy. Samples of six COVID-19 patients with a documented histopathology were systematically investigated by thin section electron microscopy. The different samples and areas inspected revealed the ultrastructural correlates of the different phases of diffuse alveolar damage, including detachment of the alveolar epithelium, hyperplasia of type 2 cells, exudates, and accumulation of extracellular material, such as the hyaline membranes and fibrin. Macrophages and neutrophilic granulocytes were regularly detected. Structural integrity of endothelium was intact in regions where the alveolar epithelium was already detached. Aggregates of erythrocytes, leukocytes with fibrin, and thrombocytes were not observed. Coronavirus particles were only found in and around very few cells in one of the six patient samples. The type and origin of these cells could not be assessed although the overall structural preservation of the samples allowed the identification of pulmonary cell types. Hence, the observed alveolar damage is not associated with virus presence or structural impairment due to ongoing replication at later stages of the disease in fatal cases, which implies that the lung damage in these patients is at least propagated by alternative mechanisms, perhaps, an inappropriate immune or stress response. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 is the causative of the COVID-19 disease, which has spread pandemically around the globe within a few months. It is therefore necessary to collect fundamental information about the disease, its epidemiology and treatment, as well as about the virus itself. While the virus has been identified rapidly, detailed ultrastructural analysis of virus cell biology and architecture is still in its infancy. We therefore studied the virus morphology and morphometry of SARS-CoV-2 in comparison to SARS-CoV as it appears in Vero cell cultures by using conventional thin section electron microscopy and electron tomography. Both virus isolates, SARS-CoV Frankfurt 1 and SARS-CoV-2 Italy-INMI1, were virtually identical at the ultrastructural level and revealed a very similar particle size distribution with a median of about 100 nm without spikes. Maximal spike length of both viruses was 23 nm. The number of spikes per virus particle was about 30% higher in the SARS-CoV than in the SARS-CoV-2 isolate. This result complements a previous qualitative finding, which was related to a lower productivity of SARS-CoV-2 in cell culture in comparison to SARS-CoV. [ABSTRACT FROM AUTHOR]

Rationale: Peripheral immune responses can be modified by associative learning procedures. Less is known, however, whether and to what extent neuroendocrine parameters can be classically conditioned. Objectives: In this randomized double-blind study, we modified an established paradigm to behaviorally condition endocrine responses in humans. Methods: Thirty-one healthy male participants received a distinctively flavored green drink as the conditioned stimulus (CS) and intravenous injections of corticotropin-releasing hormone (CRH) (CRH group, N = 17) or NaCl (placebo group, N = 14) as the unconditioned stimulus (US) during two subsequent acquisition trials. Plasma levels of cortisol and noradrenaline, heart rate, and psychological parameters were analyzed before and 15, 30, 60, 120, and 180 min after injection. The two acquisition trials were followed by two evocation trials, during which participants underwent the same procedure but now receiving NaCl injections. Results: CRH administration induced pronounced increases in cortisol and noradrenaline plasma concentrations, heart rate, and anxiety levels. However, re-exposure to the CS during evocations trials did not provoke conditioned increases in neuroendocrine parameters. Median split of the CRH group based on the cortisol baseline level into 'cort-high' and 'cort-low' subgroups showed that the 'cort-high' subgroup displayed a significantly increased cortisol production on evocation days compared to the 'cort-low' subgroup and the placebo group. Conclusion: This taste-endocrine paradigm employing CRH injection as the US in healthy male volunteers failed to induce a behaviorally conditioned cortisol release as a learned endocrine response. Future studies should clarify a possible role of higher baseline cortisol levels in perhaps facilitating a conditioned cortisol response. [ABSTRACT FROM AUTHOR]

During the last glacial cycle, greenhouse gas concentrations fluctuated on decadal and longer timescales. Concentrations of methane, as measured in polar ice cores, show a close connection with Northern Hemisphere temperature variability, but the contribution of the various methane sources and sinks to changes in concentration is still a matter of debate. Here we assess changes in methane cycling over the past 160,000 years by measurements of the carbon isotopic composition δ13C of methane in Antarctic ice cores from Dronning Maud Land and Vostok. We find that variations in the δ13C of methane are not generally correlated with changes in atmospheric methane concentration, but instead more closely correlated to atmospheric CO2 concentrations. We interpret this to reflect a climatic and CO2-related control on the isotopic signature of methane source material, such as ecosystem shifts in the seasonally inundated tropical wetlands that produce methane. In contrast, relatively stable δ13C values occurred during intervals of large changes in the atmospheric loading of methane. We suggest that most methane sources-most notably tropical wetlands-must have responded simultaneously to climate changes across these periods. [ABSTRACT FROM AUTHOR]

The Gram-positive bacterium Listeria monocytogenes occurs ubiquitously in the environment and infects humans upon ingestion. It encodes four PadR-like repressors, out of which LftR has been characterized previously and was shown to control gene expression in response to the antibiotic aurantimycin produced by other environmental bacteria. To better understand the PadR regulons of L. monocytogenes, we performed RNA-sequencing with mutants of the other three repressors LadR, LstR and Lmo0599. We show that LadR is primarily responsible for the regulation of the mdrL gene, encoding an efflux pump, while LstR and Lmo0599 mainly regulate their own operons. The lstR operon contains the lmo0421 gene, encoding a homolog of the RodA/FtsW protein family. However, this protein does not possess such functionality, as we demonstrate here. The lmo0599 operon contains two additional genes coding for the hypothetical trans-membrane proteins lmo0600 and lmo0601. A striking phenotype of the lmo0599 mutant is its impaired growth at refrigeration temperature. In light of these and other results we suggest that Lmo0599 should be renamed and propose LltR (listerial low temperature regulator) as its new designation. Based on the nature of the PadR target genes we assume that these repressors collectively respond to compounds acting on the cellular envelope. [ABSTRACT FROM AUTHOR]