Biological invasions are a population-level rather than a species-level phenomenon.

Biological invasions pose a rapidly expanding threat to the persistence, functioning and service provisioning of ecosystems globally, and to socio-economic interests. The stages of successful invasions are driven by the same mechanism that underlies adaptive changes across species in general-via natural selection on intraspecific variation in traits that influence survival and reproductive performance (i.e., fitness). Surprisingly, however, the rapid progress in the field of invasion science has resulted in a predominance of species-level approaches (such as deny lists), often irrespective of natural selection theory, local adaptation and other population-level processes that govern successful invasions. To address these issues, we analyse non-native species dynamics at the population level by employing a database of European freshwater macroinvertebrate time series, to investigate spreading speed, abundance dynamics and impact assessments among populations. Our findings reveal substantial variability in spreading speed and abundance trends within and between macroinvertebrate species across biogeographic regions, indicating that levels of invasiveness and impact differ markedly. Discrepancies and inconsistencies among species-level risk screenings and real population-level data were also identified, highlighting the inherent challenges in accurately assessing population-level effects through species-level assessments. In recognition of the importance of population-level assessments, we urge a shift in invasive species management frameworks, which should account for the dynamics of different populations and their environmental context. Adopting an adaptive, region-specific and population-focused approach is imperative, considering the diverse ecological contexts and varying degrees of susceptibility. Such an approach could improve and refine risk assessments while promoting mechanistic understandings of risks and impacts, thereby enabling the development of more effective conservation and management strategies

Taming the terminological tempest in invasion science

Standardized terminology in science is important for clarity of interpretation and communication. In invasion science — a dynamic and quickly evolving discipline — the rapid proliferation of technical terminology has lacked a standardized framework for its language development. The result is a convoluted and inconsistent usage of terminology, with various discrepancies in descriptions of damages and interventions. A standardized framework is therefore needed for a clear, universally applicable, and consistent terminology to promote more effective communication across researchers, stakeholders, and policymakers. Inconsistencies in terminology stem from the exponential increase in scientific publications on the patterns and processes of biological invasions authored by experts from various disciplines and countries since the 1990s, as well as publications by legislators and policymakers focusing on practical applications, regulations, and management of resources. Aligning and standardizing terminology across stakeholders remains a prevailing challenge in invasion science. Here, we review and evaluate the multiple terms used in invasion science (e.g. 'non-native', 'alien', 'invasive' or 'invader', 'exotic', 'non-indigenous', 'naturalized, 'pest') to propose a more simplified and standardized terminology. The streamlined framework we propose and translate into 28 other languages is based on the terms (i) 'non-native', denoting species transported beyond their natural biogeographic range, (ii) 'established non-native', i.e. those non-native species that have established self-sustaining populations in their new location(s) in the wild, and (iii) 'invasive non-native' — populations of established non-native species that have recently spread or are spreading rapidly in their invaded range actively or passively with or without human mediation. We also highlight the importance of conceptualizing 'spread' for classifying invasiveness and 'impact' for management. Finally, we propose a protocol for classifying populations based on (1) dispersal mechanism, (2) species origin, (3) population status, and (4) impact. Collectively and without introducing new terminology, the framework that we present aims to facilitate effective communication and collaboration in invasion science and management of non-native species

Total brain tissue sialic acid levels due to glutathione effect in experimental epilepsy

PubMedID: 17917923Epilepsy can be described as a group of neurological disorders, characterized by recurrent episodes of convulsive seizures, loss of consciousness, sensory disturbances, abnormal behavior, or all of these. Altered glutathione metabolism in association with increased oxidative stress has been implicated in the pathogenesis of many diseases such as seizures. It is therefore reasonable to propose that sialic acid levels can be affected by this pathological state or, alternately, by seizures. The present study showed that the sialic acid levels were significantly different between the experimental groups as well as in the subgroup analysis. The results suggest that glutathione may have a neuroprotective effect by decreasing sialic acid levels in mice brain. Copyright © 2007 Informa Healthcare USA, Inc

Effects of progesterone on total brain tissue adenosine deaminase activity in experimental epilepsy

PubMedID: 19125374Single seizure and epilepsy is one of the most commonly encountered neurologic disorders in elderly individuals, arising as a result of complex and often multiple acquired underlying pathologies. Adenosine, acting at A1 receptors, exhibits anticonvulsant effects in experimental epilepsy and inhibits progression to status epilepticus. Adenosine deaminase is the enzyme for the regulation of adenosine levels. Therefore any change in adenosine deaminase levels will reflect to adenosine levels. Adenosine deaminase levels were decreased in the groups that were given progesterone. Progesterone may have an antiseizure effect with the additional finding decreased levels of adenosine deaminase that would have resulted in increased adenosine levels that exerts anticonvulsant effect via GABA-A receptors. Further studies are needed to evaluate the role of progesterone effects on adenosine deaminase levels and its mechanism(s) in the pathogenesis. Copyright © 2009 Informa Healthcare USA, Inc

Changes in adenosine nucleotides in the heart tissue of rats following different types of death

Forty-eight Sprague-Dawley rats were killed by cervical dislocation, electric shock and drowning to investigate the correlations between types of death and levels of adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) in heart tissue after death. The hearts were taken out after death and ATP, ADP and AMP levels in the heart muscle were measured

The effect of progesterone on total brain tissue sialic acid levels in experimental epilepsy

PubMedID: 18041609Epilepsy, the most common neurological disorder worldwide, changing cellular interactions and connectivity may have effects on sialic acid levels. A total of 80 mice were separated into 8 groups: the sham, control, pentylentetrazole (PTZ), PTZ plus progesterone, five dose progesterone, single dose progesterone, kindling, and kindling plus progesterone groups. Brains of each mice were extracted and were divided into five parts. The sialic acid levels were significantly different between the groups and also in the subgroups. The results suggested that progesterone may have an anti-seizure effect by decreasing sialic acid levels in mice. Further studies are needed to evaluate the role of progesterone on sialic acid levels and its role in the epilepsy pathogenesis. Copyright © 2008 Informa Healthcare USA, Inc

The association of serum procalcitonin level with the no-reflow phenomenon after a primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction

Objective The no-reflow phenomenon is associated with adverse outcomes in patients with acute ST-elevation myocardial infarction (STEMI) treated by a primary percutaneous coronary intervention (PPCI). Procalcitonin (PCT) is a marker of systemic inflammatory states and an elevated serum PCT concentration is related to an increased risk of cardiovascular events. We aimed to assess whether serum PCT level at admission is an independent predictor of no-reflow in patients with STEMI treated with PPCI