Circumstances and causes of sudden circulatory arrests in the Dutch province of Limburg and the involvement of citizen rescuers

Background

Recently we showed that a citizen volunteer system using text message alerts improves survival of out-of-hospital sudden circulatory arrest (OHCA). It is important to characterise the OHCA population encountered by the volunteers regarding circumstances and causes of the arrests.

Methods and Results

Eligible for this study were 968 OHCAs that occurred between April 2012 and April 2014 in the Dutch province of Limburg. The distribution of causes of OHCA, patient characteristics and resuscitation settings were compared between 492 arrests wherein volunteers were notified and 476 arrests where the dispatcher decided not to do so.In case of notification, the cause of OHCA was known in 345 cases and of cardiac origin (treatable) in 83.2% (287/345). About 41% of the cardiac arrests were caused by acute or chronic coronary artery disease. OHCA occurred within the home environment in about 84%. The OHCA was witnessed in 75% of the cases. In 60.9% of the cases a witness or bystander had already started basic life support. However, in approximately 18% of the OHCAs the volunteer was the first to start basic life support before arrival of the ambulance. In about 75% of the OHCAs the ambulance arrived at 6 minutes or later after time of notification by the dispatch centre.

Conclusion

The volunteer system is predominantly activated in situations for which it was developed; cases with cardiac aetiology (58%) and cases in the home environment (84%). The majority of patients encountered by the volunteers had ‘hearts too good to die’, underscoring the benefit of deploying citizen rescuers in programs to improve survival of OHCA.

     

Substrate-Induced Regulation of Gene Expression in the Pancreas

Synthesis and secretion rates of pancreatic proteins, particularly of the (pro)enzymes, have been studied under different conditions and in several animal systems. This brief overview will focus on the levels of mRNA, the rates of protein synthesis and protein secretion in the pancreas under controlled dietary regimens.     

Pathways of unauthorized fish introductions and types of management responses

The study of the relationships among environmental factors, primary production, zooplankton community, and feeding behavior of fish species represents a key aspect to obtain a deeper knowledge of biological processes acting at ecosystem level. In this context, oceanographic data and biological samples were collected in two different surveys, carried out during late June 2011 and early July 2015 in the Strait of Sicily (Central Mediterranean Sea). Differences in abundance, biomass, and assemblage structure of zooplankton and anchovy (Engraulis encrasicolus Linnaeus, 1758) population were observed between the two surveys. Still, zooplankton biomass was significantly correlated to longitude, chlorophyll a recorded during the surveys (as a proxy of primary production), and oxygen concentrations. Such differences affected the isotopic composition of anchovy, which showed changes in δ¹⁵N and δ¹³C values between the two surveys. Mixing models identified different contributions of food sources in the two sampling periods, i.e., major consumption on large copepods and euphausiids in 2015 with respect to 2011, which was consistent with a greater availability of these preys in the environment in 2015. The obtained results evidenced that E. encrasicolus may be affected by any environmental change that influences the plankton community, which is the basis of the diet of these fishes. Such findings highlighted the importance to further investigate the trophic relationships among different compartments of the food web, as well as the possible environmental influences, in order to obtain a more complete picture of ecosystem functioning and also in the light of an ecosystem-based approach to fisheries management.     

Host persistence or extinction from emerging infectious disease: insights from white-nose syndrome in endemic and invading regions

Predicting species'' fates following the introduction of a novel pathogen is a significant and growing problem in conservation. Comparing disease dynamics between introduced and endemic regions can offer insight into which naive hosts will persist or go extinct, with disease acting as a filter on host communities. We examined four hypothesized mechanisms for host–pathogen persistence by comparing host infection patterns and environmental reservoirs for Pseudogymnoascus destructans (the causative agent of white-nose syndrome) in Asia, an endemic region, and North America, where the pathogen has recently invaded. Although colony sizes of bats and hibernacula temperatures were very similar, both infection prevalence and fungal loads were much lower on bats and in the environment in Asia than North America. These results indicate that transmission intensity and pathogen growth are lower in Asia, likely due to higher host resistance to pathogen growth in this endemic region, and not due to host tolerance, lower transmission due to smaller populations, or lower environmentally driven pathogen growth rate. Disease filtering also appears to be favouring initially resistant species in North America. More broadly, determining the mechanisms allowing species persistence in endemic regions can help identify species at greater risk of extinction in introduced regions, and determine the consequences for disease dynamics and host–pathogen coevolution.     

Comparative experimental taphonomy of eight marine arthropods indicates distinct differences in preservation potential

Global biodiversity patterns in deep time can only be understood fully when the relative preservation potential of each clade is known. The relative preservation potential of marine arthropod clades, a diverse and ecologically important component of modern and past ecosystems, is poorly known. We tackled this issue by carrying out a 205‐day long comprehensive, comparative, taphonomic experiment in a laboratory by scoring up to ten taphonomic characters for multiple specimens of seven crustacean and one chelicerate species (two true crabs, one shrimp, one lobster, one hermit crab, one stomatopod, one barnacle and one horseshoe crab). Although the results are preliminary because we used a single experimental setup and algal growth partially hampered observations, some parts of hermit crabs, stomatopods, swimming crabs and barnacles decayed slowly relative to other parts, implying differential preservation potentials within species, largely consistent with the fossil record of these groups. An inferred parasitic isopod, manifested by a bopyriform swelling within a hermit crab carapace, decayed relatively fast. We found limited variation in the decay rate between conspecifics, and we did not observe size‐related trends in decay rate. Conversely, substantial differences in the decay rate between species were seen after c. 50 days, with shrimps and stomatopods decaying fastest, suggesting a relatively low preservation potential, whereas the lobster, calico crabs, horseshoe crabs and barnacles showed relatively slow decay rates, suggesting a higher preservation potential. These results are supported by two modern and fossil record‐based preservation potential metrics that are significantly correlated to decay rate ranks. Furthermore, we speculate that stemward slippage may not be ubiquitous in marine arthropods. Our results imply that diversity studies of true crabs, lobsters, horseshoe crabs and barnacles are more likely to yield patterns that are closer to their true biodiversity patterns than those for stomatopods, shrimps and hermit crabs.