Prey Nutritional Quality Interacts With Chemical Defenses to Affect Consumer Feeding and Fitness

Numerous studies have assessed the individual effects of prey nutritional quality or chemical defenses on consumer feeding behavior. However, little is known about how these traits interact to affect consumer feeding and performance. We tested the separate and interactive effects of prey chemical defenses and nutritional quality on the feeding behavior and fitness of six sympatric crustacean mesograzers. Natural concentrations of diterpene alcohols (dictyols) from the brown alga Dictyota menstrualis were incorporated, or not incorporated, into lower quality and higher quality foods to create artificial diets mimicking prey of variable value and defense. Five amphipods (Ampithoe longimana, A. valida, Cymadusa compta, Gammarus mucronatus, and Elasmopus levis) and one isopod (Paracerceis caudata), representing a continuum of closely to distantly related organisms, were fed intact algae or lower and higher quality diets containing or lacking dictyols. All six mesograzers preferred the green alga Enteromorpha intestinalis to the dictyol producing alga Dictyota menstrualis. In assays allowing consumers to choose between simultaneously available foods, dictyols deterred feeding by all five amphipods, but not the isopod; this occurred for both lower and higher quality foods. In no-choice assays, where consumers were confined with only one of our four treatment diets, effects on feeding became more complex. Nutritional quality alone affected feeding by five of the six species. These grazers compensated for lower quality by increasing consumption. Dictyols suppressed feeding for four of the six species. More interestingly, there were significant dictyol X quality interactions for three species. Dictyols decreased feeding more when placed in lower quality foods than higher quality foods. Two amphipods deterred by dictyols in the choice assays readily consumed dictyol-containing foods in no-choice situations and suffered few negative effects of doing so. Although all amphipods were deterred by dictyols in choice assays, dictyols decreased fitness (survivorship, growth, or reproduction) for only four of the five species. These effects included large and immediate decreases in survivorship, dramatic effects on reproduction, and modest effects on female growth. Dictyols enhanced survivorship of the isopod. Thus, the effects of secondary metabolites on feeding in choice situations vs. fitness in long-term assays were inconsistent. For three amphipods, certain effects of food quality, dictyols, or their interaction were detected only for females. In general, negative effects of dictyols on fitness were greater in lower than in higher quality foods, suggesting that prey nutritional value may counteract the effects of defensive metabolites. For example, when G. mucronatus consumed dictyols in lower quality foods, mortality was \u3e80% by day 5; for dictyols in higher quality foods, 80% mortality took 28 days to develop. Lower quality foods alone significantly decreased growth for the isopod, three of the amphipods, and the females of a fourth amphipod, concomitantly reducing fecundity for four of the five amphipods studied. The effects of both chemical defenses and nutritional quality were unrelated to consumer phylogeny; responses of congeners varied as much, or more, than responses of more distantly related consumers. Understanding mechanisms and consequences of food selection requires that the interactive effects of both chemical defenses and prey nutritional characteristics be considered explicitly

Complications in pulmonary vein isolation in the Netherlands Heart Registration differ with sex and ablation technique

Aims Pulmonary vein isolation (PVI) has become a cornerstone of the invasive treatment of atrial fibrillation. Severe complications are reported in 1-3% of patients. This study aims to compare complications and follow-up outcome of PVI in patients with atrial fibrillation. Methods and results The data were extracted from the Netherlands Heart Registration. Procedural and follow-up outcomes in patients treated with conventional radiofrequency (C-RF), multielectrode phased RF (Ph-RF), or cryoballoon (CB) ablation from 2012 to 2017 were compared. Subgroup analysis was performed to identify variables associated with complications and repeat ablations. In total, 13 823 patients (69% male) were included. The reported complication incidence was 3.6%. Patients treated with C-RF developed more cardiac tamponades (C-RF 0.8% vs. Ph-RF 0.3% vs. CB 0.3%, P Conclusion The reported complication rate during PVI was low. Patients treated with C-RF ablation were more likely to develop cardiac tamponades and vascular complications. Female sex was associated with more cardiac tamponade and bleeding complications

High prevalence of non-accidental trauma among deceased children presenting at Level I trauma centers in the Netherlands

PURPOSE: Between 0.1—3% of injured children who present at a hospital emergency department ultimately die as a result of their injuries. These events are typically reported as unnatural causes of death and may result from either accidental or non-accidental trauma (NAT). Examples of the latter include trauma that is inflicted directly or resulting from neglect. Although consultation with a forensic physician is mandatory for all deceased children, the prevalence of fatal inflicted trauma or neglect among children is currently unclear. METHODS: This is a retrospective study that included children (0–18 years) who presented and died at one of the 11 Level I trauma centers in the Netherlands between January 1, 2014, and January 1, 2019. Outcomes were classified based on the conclusions of the Child Abuse and Neglect team or those of forensic pathologists and/or the court in cases referred for legally mandated autopsies. Cases in which conclusions were unavailable and there was no clear accidental cause of death were reviewed by an expert panel. RESULTS: The study included 175 cases of childhood death. Seventeen (9.7%) of these children died due to inflicted trauma (9.7%), 18 (10.3%) due to neglect, and 140 (80%) due to accidents. Preschool children (< 5 years old) were significantly more likely to present with injuries due to inflicted trauma and neglect compared to older children (44% versus 6%, p < 0.001, odds ratio [OR] 5.80, 95% confidence interval [CI] 2.66–12.65). Drowning accounted for 14 of the 18 (78%) pediatric deaths due to neglect, representing 8% of the total cases. Postmortem radiological studies and autopsies were performed on 37 (21%) of all cases of childhood death. CONCLUSION: One of every five pediatric deaths in our nationwide Level I trauma center study was attributed to NAT; 44% of these deaths were the result of trauma experienced by preschool-aged children. A remarkable number of fatal drownings were due to neglect. Postmortem radiological studies and autopsies were performed in only one-fifth of all deceased children. The limited use of postmortem investigations may have resulted in missed cases of NAT, which will result in an overall underestimation of fatal NAT experienced by children. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12024-021-00416-7

ICDP workshop on the Lake Tanganyika Scientific Drilling Project: a late Miocene–present record of climate, rifting, and ecosystem evolution from the world's oldest tropical lake

The Neogene and Quaternary are characterized by enormous changes in global climate and environments, including global cooling and the establishment of northern high-latitude glaciers. These changes reshaped global ecosystems, including the emergence of tropical dry forests and savannahs that are found in Africa today, which in turn may have influenced the evolution of humans and their ancestors. However, despite decades of research we lack long, continuous, well-resolved records of tropical climate, ecosystem changes, and surface processes necessary to understand their interactions and influences on evolutionary processes. Lake Tanganyika, Africa, contains the most continuous, long continental climate record from the mid-Miocene (∼10 Ma) to the present anywhere in the tropics and has long been recognized as a top-priority site for scientific drilling. The lake is surrounded by the Miombo woodlands, part of the largest dry tropical biome on Earth. Lake Tanganyika also harbors incredibly diverse endemic biota and an entirely unexplored deep microbial biosphere, and it provides textbook examples of rift segmentation, fault behavior, and associated surface processes. To evaluate the interdisciplinary scientific opportunities that an ICDP drilling program at Lake Tanganyika could offer, more than 70 scientists representing 12 countries and a variety of scientific disciplines met in Dar es Salaam, Tanzania, in June 2019. The team developed key research objectives in basin evolution, source-to-sink sedimentology, organismal evolution, geomicrobiology, paleoclimatology, paleolimnology, terrestrial paleoecology, paleoanthropology, and geochronology to be addressed through scientific drilling on Lake Tanganyika. They also identified drilling targets and strategies, logistical challenges, and education and capacity building programs to be carried out through the project. Participants concluded that a drilling program at Lake Tanganyika would produce the first continuous Miocene–present record from the tropics, transforming our understanding of global environmental change, the environmental context of human origins in Africa, and providing a detailed window into the dynamics, tempo and mode of biological diversification and adaptive radiations.© Author(s) 2020. This open access article is distributed under the Creative Commons Attribution 4.0 License

Quantifying system disturbance and recovery from historical mining-derived metal contamination at Brotherswater, northwest England

The final publication is available at Springer via https://doi.org/10.1007/s10933-016-9907-1Metal ore extraction in historical times has left a legacy of severe contamination in aquatic ecosystems around the world. In the UK, there are ongoing nationwide surveys of present-day pollution discharged from abandoned mines but few assessments of the magnitude of contamination and impacts that arose during historical metal mining have been made. We report one of the first multi-centennial records of lead (Pb), zinc (Zn) and copper (Cu) fluxes into a lake (Brotherswater, northwest England) from point-sources in its catchment (Hartsop Hall Mine and Hogget Gill processing plant) and calculate basin-scale inventories of those metals. The pre-mining baseline for metal contamination has been established using sediment cores spanning the past 1,500 years and contemporary material obtained through sediment trapping. These data enabled the impact of 250 years of local, small-scale mining (1696 – 1942) to be quantified and an assessment of the trajectory towards system recovery to be made. The geochemical stratigraphy displayed in twelve sediment cores show strong correspondence to the documented history of metal mining and processing in the catchment. The initial onset in 1696 was detected, peak Pb concentrations (>10,000 µg g-1) and flux (39.4 g m-2 y-1) corresponded to the most intensive mining episode (1863-1871) and 20th century technological enhancements were reflected as a more muted sedimentary imprint. After careful evaluation, we used these markers to augment a Bayesian age-depth model of the independent geochronology obtained using radioisotope dating (14C, 210Pb, 137Cs and 241Am). Total inventories of Pb, Zn and Cu for the lake basin during the period of active mining were 15,415 kg, 5,897 kg and 363 kg, respectively. The post-mining trajectories for Pb and Zn project a return to pre-mining levels within 54-128 years for Pb and 75-187 years for Zn, although future remobilisation of metal-enriched catchment soils and floodplain sediments could perturb this recovery. We present a transferable paleolimnological approach that highlights flux-based assessments are vital to accurately establish the baseline, impact and trajectory of mining-derived contamination for a lake catchment

The nucleophilic amino group of lysine is central for histone lysine methyltransferase catalysis

Contains fulltext : 208586.pdf (publisher's version ) (Open Access

Structure-Activity Relationship Studies on (R)-PFI-2 Analogues as Inhibitors of Histone Lysine Methyltransferase SETD7

Contains fulltext : 193974.pdf (Publisher’s version ) (Open Access

Quantification of the Emetic Toxin Cereulide in Food Products by Liquid Chromatography-Mass Spectrometry Using Synthetic Cereulide as a Standard▿

Bacillus cereus produces the emetic toxin cereulide, a cyclic dodecadepsipeptide that can act as a K+ ionophore, dissipating the transmembrane potential in mitochondria of eukaryotic cells. Because pure cereulide has not been commercially available, cereulide content in food samples has been expressed in valinomycin equivalents, a highly similar cyclic potassium ionophore that is commercially available. This research tested the biological activity of synthetic cereulide and validated its use as a standard in the quantification of cereulide contents in food samples. The synthesis route consists of 10 steps that result in a high yield of synthetic cereulide that showed biological activity in the HEp-2 cell assay and the boar sperm motility assay. The activity is different in both methods, which may be attributed to differences in K+ content of the test media used. Using cereulide or valinomycin as a standard to quantify cereulide based on liquid chromatography-mass spectrometry (LC-MS), the concentration determined with cereulide as a standard was on average 89.9% of the concentration determined using valinomycin as a standard. The recovery experiments using cereulide-spiked food products and acetonitrile as extraction solute showed that the LC-MS method with cereulide as a standard is a reliable and accurate method to quantify cereulide in food, because the recovery rate was close to 100% over a wide concentration range

Complete Deracemization of Proteinogenic Glutamic Acid Using Viedma Ripening on a Metastable Conglomerate

Viedma ripening is a process in which a compound that forms a stable racemic conglomerate can be converted to an enantiomerically pure solid state. Combining this deracemization process with Ostwald’s rule of stages, allows Viedma ripening to be extended to a racemic compound for which the conglomerate exists only in a metastable form. This is demonstrated for glutamic acid, a proteinogenic amino acid. Since Ostwald ripening is one of the processes occurring during Viedma ripening, we thus make use of Ostwald twice