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1.
Ecol Evol ; 14(4): e11202, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38571798

RESUMEN

Understanding the diet preferences and food selection of invasive species is crucial to better predict their impact on community structure and ecosystem functioning. Limnomysis benedeni, a Ponto-Caspian invasive mysid shrimp, is one of the most successful invaders in numerous European river and lake ecosystems. While existing studies suggest potentially strong trophic impact due to high predation pressure on native plankton communities, little is known of its food selectivity between phyto- and zooplankton, under different food concentrations. Here, we therefore investigated the feeding selectivity of L. benedeni on two commonly occurring prey organisms in freshwaters, the small rotifer zooplankton Brachionus calyciflorus together with the microphytoplankton Cryptomonas sp. present in increasing densities. Our results demonstrated a clear shift in food selection, with L. benedeni switching from B. calyciflorus to Cryptomonas sp. already when the two prey species were provided in equal biomasses. Different functional responses were observed for the two food types, indicating somewhat different foraging mechanisms for each food type. These findings provide experimental evidence on the feeding flexibility of invasive mysid shrimps and potential implications for trophic interactions in invaded ecosystems.

2.
Front Cardiovasc Med ; 11: 1338066, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38450368

RESUMEN

Introduction: Kinetics of stress-related biological parameters were determined in acute coronary syndrome (ACS) patients undergoing complex cardiovascular rehabilitation. Methods: We determined platelet functionality in the absence/presence of a selective alpha-2 adrenergic receptor inhibitor, atipemazole parallel with salivary cortisol levels at enrolment, and at 3- and 12-months follow-up in 75 ACS patients with percutaneous coronary intervention. Results: Pharmacological/non-pharmacological secondary prevention methods have been efficiently applied. Baseline aggregometry indicated platelet hyperactivity, decreasing gradually and being significantly reduced late, at 12 months (p < 0.05). Cortisol levels followed similar kinetics (p < 0.05). Baseline epinephrine-induced aggregations (EIA) significantly correlated with most of the other platelet agonists, even at subsequent time-points. Patients with upper-quartile EIA at enrolment (EIA-UQ) had significantly higher ADP- and collagen-induced aggregations at enrolment, at 3- and 12-months follow-up as well, indicating that high adrenergic response in the acute phase is accompanied by general platelet hyperactivity and predicts sustained platelet activation. In the EIA-UQ group higher cardiac biomarker release, elevated C-reactive protein and cortisol levels, and lower baseline left ventricular ejection fraction were detected.Atipemazole significantly reduced platelet aggregation induced by several platelet agonists, being most potent and comparable to full in vitro P2Y12 inhibition on collagen-induced aggregations (p < 0.05), indicating that catecholamines might serve as promt/long-term modulators of platelet function. Discussion: Despite effective CCR programme and dual antiplatelet therapy, prolonged activation of sympathetic neuroendocrine system and general platelet hyperactivity can be detected up to one year in ACS patients with high adrenergic platelet activity. Moreover, initial high adrenergic activity is accompanied by clinical parameters associated to increased cardiovascular risk, therefore early identification of these patients might support complex optimal long-term therapy.

3.
Proc Biol Sci ; 291(2016): 20231917, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38320606

RESUMEN

Understanding the spatial scales at which organisms can adapt to strong natural and human-induced environmental gradients is important. Salinization is a key threat to biodiversity, ecosystem functioning and the provision of ecosystem services of freshwater systems. Clusters of naturally saline habitats represent ideal test cases to study the extent and scale of local adaptation to salinization. We studied local adaptation of the water flea Daphnia magna, a key component of pond food webs, to salinity in two contrasting landscapes-a dense cluster of sodic bomb crater ponds and a larger-scale cluster of soda pans. We show regional differentiation in salinity tolerance reflecting the higher salinity levels of soda pans versus bomb crater ponds. We found local adaptation to differences in salinity levels at the scale of tens of metres among bomb crater pond populations but not among geographically more distant soda pan populations. More saline bomb crater ponds showed an upward shift of the minimum salt tolerance observed across clones and a consequent gradual loss of less tolerant clones in a nested pattern. Our results show evolutionary adaptation to salinity gradients at different spatial scales, including fine-tuned local adaptation in neighbouring habitat patches in a natural landscape.


Asunto(s)
Ecosistema , Tolerancia a la Sal , Animales , Biodiversidad , Daphnia , Agua Dulce , Salinidad
4.
Sci Rep ; 13(1): 3243, 2023 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-36828901

RESUMEN

Temporary ponds are among the most sensitive aquatic habitats to climate change. Their microbial communities have crucial roles in food webs and biogeochemical cycling, yet how their communities are assembled along environmental gradients is still understudied. This study aimed to reveal the environmental drivers of diversity (OTU-based richness, evenness, and phylogenetic diversity) and community composition from a network of saline temporary ponds, soda pans, in two consecutive spring seasons characterized by contrasting weather conditions. We used DNA-based molecular methods to investigate microbial community composition. We tested the effect of environmental variables on the diversity of prokaryotic (Bacteria, Cyanobacteria) and microeukaryotic functional groups (ciliates, heterotrophic flagellates and nanoflagellates, fungi, phytoplankton) within and across the years. Conductivity and the concentration of total suspended solids and phosphorus were the most important environmental variables affecting diversity patterns in all functional groups. Environmental conditions were harsher and they also had a stronger impact on community composition in the dry spring. Our results imply that these conditions, which are becoming more frequent with climate change, have a negative effect on microbial diversity in temporary saline ponds. This eventually might translate into community-level shifts across trophic groups with changing local conditions with implications for ecosystem functioning.


Asunto(s)
Cianobacterias , Ecosistema , Filogenia , Cadena Alimentaria , Aguas Salinas , Biodiversidad
5.
Ecology ; 103(6): e3683, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35307820

RESUMEN

In metacommunity ecology, a major focus has been on combining observational and analytical approaches to identify the role of critical assembly processes, such as dispersal limitation and environmental filtering, but this work has largely ignored temporal community dynamics. Here, we develop a "virtual ecologist" approach to evaluate assembly processes by simulating metacommunities varying in three main processes: density-independent responses to abiotic conditions, density-dependent biotic interactions, and dispersal. We then calculate a number of commonly used summary statistics of community structure in space and time and use random forests to evaluate their utility for inferring the strength of these three processes. We find that (i) both spatial and temporal data are necessary to disentangle metacommunity processes based on the summary statistics we test, and including statistics that are measured through time increases the explanatory power of random forests by up to 59% compared to cases where only spatial variation is considered; (ii) the three studied processes can be distinguished with different descriptors; and (iii) each summary statistic is differently sensitive to temporal and spatial sampling effort. Including repeated observations of metacommunities over time was essential for inferring the metacommunity processes, particularly dispersal. Some of the most useful statistics include the coefficient of variation of species abundances through time and metrics that incorporate variation in the relative abundances (evenness) of species. We conclude that a combination of methods and summary statistics is probably necessary to understand the processes that underlie metacommunity assembly through space and time, but we recognize that these results will be modified when other processes or summary statistics are used.


Asunto(s)
Biodiversidad , Ecosistema , Ecología
6.
Langenbecks Arch Surg ; 407(5): 1839-1850, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35233644

RESUMEN

BACKGROUND: Laparoscopic gastric plication (LGP) often requires reoperative bariatric surgery (RBS) due to complications and insufficient weight loss. The aim of our study was to assess perioperative morbidity and weight loss during follow-up in patients undergoing RBS after primary LGP for morbid obesity. METHODS: A search of PubMed, Web of Science, Cochrane Library, and Google Scholar was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines using ("conversion"OR "revision*""OR "reoperat*")AND("gastric"OR "curvatur*")AND "plication." Studies were deemed eligible if data on RBS after LGP were provided. For each study, data were extracted and analyzed. RESULTS: In the literature review, 291 articles were screened and 7 included. The studies covered a total of 367 patients, of whom 119 received a sleeve gastrectomy (SG), 85 a Roux-en-y gastric bypass (RYGB), 75 a one anastomosis-gastric bypass (OAGB), 45 a re-LGP, and 25 a jejuno-ileal bypass. After RBS, excess weight loss was 50.8 ± 6.5% at 6 months, 71.0 ± 7.7% at 12 months, and 89.0 ± 7.8% at 24 months. Operative time was 101.3 ± 14.6 min. Postoperatively, 18/255 patients (7.1%) had a complication, and leakage and reoperations were reported in 6/255 (2.4%) and 5/255 (2.0%) patients, respectively. Length of hospital stay was 3.1 ± 2.4 days. The quality of evidence was rated as "very low." CONCLUSIONS: Despite limitations, this systematic review and meta-analysis showed that RBS after LGP has an acceptable rate of complications and is effective in terms of excess weight loss during follow-up. No specific operation (e.g., SG, RYGB, OAGB) can be suggested over another due to the lack of evidence.


Asunto(s)
Cirugía Bariátrica , Derivación Gástrica , Laparoscopía , Obesidad Mórbida , Gastrectomía/efectos adversos , Derivación Gástrica/efectos adversos , Humanos , Laparoscopía/efectos adversos , Obesidad Mórbida/cirugía , Reoperación/efectos adversos , Estudios Retrospectivos , Resultado del Tratamiento , Pérdida de Peso
7.
Trends Ecol Evol ; 37(5): 440-453, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35058082

RESUMEN

The widespread salinisation of freshwater ecosystems poses a major threat to the biodiversity, functioning, and services that they provide. Human activities promote freshwater salinisation through multiple drivers (e.g., agriculture, resource extraction, urbanisation) that are amplified by climate change. Due to its complexity, we are still far from fully understanding the ecological and evolutionary consequences of freshwater salinisation. Here, we assess current research gaps and present a research agenda to guide future studies. We identified different gaps in taxonomic groups, levels of biological organisation, and geographic regions. We suggest focusing on global- and landscape-scale processes, functional approaches, genetic and molecular levels, and eco-evolutionary dynamics as key future avenues to predict the consequences of freshwater salinisation for ecosystems and human societies.


Asunto(s)
Ecosistema , Agua Dulce , Biodiversidad , Evolución Biológica , Cambio Climático , Humanos
8.
Sci Rep ; 11(1): 22866, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34819546

RESUMEN

Pleistocene glaciations had a tremendous impact on the biota across the Palaearctic, resulting in strong phylogeographic signals of range contraction and rapid postglacial recolonization of the deglaciated areas. Here, we explore the diversity patterns and history of two sibling species of passively dispersing taxa typical of temporary ponds, fairy shrimps (Anostraca). We combine mitochondrial (COI) and nuclear (ITS2 and 18S) markers to conduct a range-wide phylogeographic study including 56 populations of Branchinecta ferox and Branchinecta orientalis in the Palaearctic. Specifically, we investigate whether their largely overlapping ranges in Europe resulted from allopatric differentiation in separate glacial refugia followed by a secondary contact and reconstruct their postglacial recolonization from the inhabited refugia. Our results suggest the existence of distinct refugia for the two species, with genetic divergence among intraspecific lineages consistent with late Pleistocene glacial cycles. While B. ferox lineages originated from Mediterranean refugia, the origin of B. orientalis lineages was possibly located on the Pannonian Plain. We showed that most dispersal events predominantly happened within 100 km, coupled with several recent long-distance events (> 1000 km). Hence the regional habitat density of suitable habitats in Central Europe is possibly a key to the co-existence of the two species. Overall, our study illustrates how isolation in combination with stochastic effects linked to glacial periods are important drivers of the allopatric differentiation of Palaearctic taxa.


Asunto(s)
Anostraca/genética , ADN Mitocondrial/genética , Evolución Molecular , Variación Genética , Animales , Ecosistema , Flujo Genético , Haplotipos , Modelos Genéticos , Filogenia , Filogeografía , Estanques , Dinámica Poblacional , Procesos Estocásticos
9.
Sci Rep ; 10(1): 19871, 2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-33199773

RESUMEN

Astatic soda pans of the Pannonian Steppe are unique environments with respect to their multiple extreme physical and chemical characteristics (high daily water temperature fluctuation, high turbidity, alkaline pH, salinity, polyhumic organic carbon concentration, hypertrophic state and special ionic composition). However, little is known about the seasonal dynamics of the bacterial communities inhabiting these lakes and the role of environmental factors that have the main impact on their structure. Therefore, two soda pans were sampled monthly between April 2013 and July 2014 to reveal changes in the planktonic community. By late spring in both years, a sudden shift in the community structure was observed, the previous algae-associated bacterial communities had collapsed, resulting the highest ratio of Actinobacteria within the bacterioplankton (89%, with the dominance of acIII-A1 lineage) ever reported in the literature. Before these peaks, an extremely high abundance (> 10,000 individuum l-1) of microcrustaceans (Moina brachiata and Arctodiaptomus spinosus) was observed. OTU-based statistical approaches showed that in addition to algal blooms and water-level fluctuations, zooplankton densities had the strongest effect on the composition of bacterial communities. In these extreme environments, this implies a surprisingly strong, community-shaping top-down role of microcrustacean grazers.


Asunto(s)
Actinobacteria/clasificación , Cladóceros/microbiología , Copépodos/microbiología , Lagos/microbiología , Fitoplancton/microbiología , Zooplancton/microbiología , Actinobacteria/genética , Actinobacteria/crecimiento & desarrollo , Animales , ADN Bacteriano/genética , Ambientes Extremos , Pradera , Herbivoria , Filogenia , Fitoplancton/clasificación , Salinidad , Estaciones del Año , Análisis de Secuencia de ADN , Zooplancton/clasificación
10.
Ecol Lett ; 23(9): 1314-1329, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32672410

RESUMEN

The metacommunity concept has the potential to integrate local and regional dynamics within a general community ecology framework. To this end, the concept must move beyond the discrete archetypes that have largely defined it (e.g. neutral vs. species sorting) and better incorporate local scale species interactions and coexistence mechanisms. Here, we present a fundamental reconception of the framework that explicitly links local coexistence theory to the spatial processes inherent to metacommunity theory, allowing for a continuous range of competitive community dynamics. These dynamics emerge from the three underlying processes that shape ecological communities: (1) density-independent responses to abiotic conditions, (2) density-dependent biotic interactions and (3) dispersal. Stochasticity is incorporated in the demographic realisation of each of these processes. We formalise this framework using a simulation model that explores a wide range of competitive metacommunity dynamics by varying the strength of the underlying processes. Using this model and framework, we show how existing theories, including the traditional metacommunity archetypes, are linked by this common set of processes. We then use the model to generate new hypotheses about how the three processes combine to interactively shape diversity, functioning and stability within metacommunities.


Asunto(s)
Ecosistema , Modelos Biológicos , Biota , Ecología , Dinámica Poblacional
11.
Oecologia ; 193(2): 489-502, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32504109

RESUMEN

Growing evidence suggests that global climate change promotes the dominance of mixotrophic algae especially in oligotrophic aquatic ecosystems. While theory predicts that mixotrophy increases trophic transfer efficiency in aquatic food webs, deleterious effects of some mixotrophs on consumers have also been reported. Here, using a widespread mixotrophic algal genus Dinobryon, we aimed to quantify how colonial taxa contribute to secondary production in lakes. We, therefore, studied the dietary effects of Dinobryon divergens on Cladocera (Daphnia longispina) and Copepoda (Eudiaptomus gracilis), representing two main taxonomic and functional groups of zooplankton. In feeding experiments, we showed that Dinobryon was largely grazing resistant and even inhibited the uptake of the high-quality reference food in Daphnia. Eudiaptomus could to some extent compensate with selective feeding, but a negative long-term food quality effect was also evident. Besides, Eudiaptomus was more sensitive to the pure diet of Dinobryon than Daphnia. Low lipid content and high C:P elemental ratio further supported the low nutritional value of the mixotroph. In a stable isotope approach analysing a natural plankton community, we found further evidence that carbon of Dinobryon was not conveyed efficiently to zooplankton. Our results show that the increasing dominance of colonial mixotrophs can result in reduced dietary energy transfer to consumers at higher trophic levels. In a wider perspective, global climate change favours the dominance of some detrimental mixotrophic algae which may constrain pelagic trophic transfer efficiency in oligotrophic systems, similarly to cyanobacteria in eutrophic lakes.


Asunto(s)
Ecosistema , Zooplancton , Animales , Cadena Alimentaria , Calidad de los Alimentos , Lagos
12.
Ecol Lett ; 22(6): 1019-1027, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30932319

RESUMEN

When habitats are lost, species are lost in the region as a result of the sampling process. However, it is less clear what happens to biodiversity in the habitats that remain. Some have argued that the main influence of habitat loss on biodiversity is simply due to the total amount of habitat being reduced, while others have argued that fragmentation leads to fewer species per site because of altered spatial connectance among extant habitats. Here, we use a unique data set on invertebrate species in ponds spanning six decades of habitat loss to show that both regional and local species richness declined, indicating that species loss is compounded by habitat loss via connectivity loss, and not a result of a sampling process or changes in local environmental conditions. Overall, our work provides some of the clearest evidence to date from a longitudinal study that habitat loss translates into species loss, even within the remaining habitats.


Asunto(s)
Biodiversidad , Ecosistema , Estudios Longitudinales , Estanques
13.
Freshw Biol ; 63(4): 380-391, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29937596

RESUMEN

Species diversity is affected by processes operating at multiple spatial scales, although the most relevant scales that contribute to compositional variation and the temporal shifts of the involved mechanisms remain poorly explored. We studied spatial patterns of phytoplankton, rotifers and microcrustacean diversity across scales in a river floodplain system of the Danube in Austria under contrasting hydrological conditions (post-flood versus low water level).The species turnover between water sections (ß2) and between wetlands (ß3) was the major components of regional diversity for all studied groups, with species turnover between habitats (ß1) as a minor contributor. ß1 diversity and ß2 diversity were lower than expected by chance in most cases, suggesting that communities are more homogeneous than expected at these scales. ß3 diversity was higher than expected by chance in many cases, indicating more distinct communities at the wetland level. Patterns were highly similar under different hydrological conditions, indicating no major immediate effect of flood events.Local environmental and spatial factors were similarly important in structuring phytoplankton, rotifer and microcrustacean communities in both hydrological conditions. Relevant environmental factors were spatially structured in post-flood conditions especially between sections, suggesting flood-driven homogenisation within the wetlands. Under low water level, spatial structuring of environment decreased and pure environmental factors gained relevance for phytoplankton and rotifers.Our results suggest that although ß2 diversity between water sections is a major component of regional diversity, long-term spatial processes responding to connectivity across the wetland structure phytoplankton, rotifer and microcrustacean communities. Aquatic sections within the limited spatial extent of the remaining floodplain areas appear more homogeneous than expected probably due to flood recurrence over the years.These results highlight that adequate planning of restoration and conservation strategies of floodplain wetlands should consider environmental heterogeneity together with long-term spatial processes.

14.
Inland Waters ; 7(1): 3-13, 2017 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-28824797

RESUMEN

Lakes in the Alps represent a considerable fraction of nutrient-poor lakes in Central Europe, with unique biodiversity and ecosystem properties. Although some individual lakes are well studied, less knowledge is available on large-scale patterns essential to general understanding of their functioning. Here, we aimed to describe crustacean zooplankton communities (Cladocera, Copepoda) and identify their environmental drivers in the pelagic zone of 54 oligotrophic lakes in the montane region of the Alps (400-1200 m) in Austria, Germany, and Switzerland, covering a spatial scale of 650 km. Moreover, we aimed to provide data on the distribution and ecological requirements of the North American invader Bythotrephes longimanus in its Central European native range. Communities were mainly dominated by widespread species typical of lowland habitats, and only a few true specialists of oligotrophic alpine lakes were present. The most frequent taxa were the Daphnia longispina complex and Eudiaptomus gracilis, with 48 and 45 occurrences, respectively. Species richness decreased with altitude and increased with lake area. The main structuring factors of community composition were chlorophyll a concentration and depth, which drove an apparent separation of mesotrophic and oligotrophic communities. Bythotrephes had 13 occurrences, showing a preference for deep oligotrophic lakes. Its presence was not coupled with lower crustacean species richness, as was repeatedly observed in North America. Additionally, it frequently co-occurred with the other large predatory cladoceran, Leptodora kindtii. B. longimanus might be considered a truly montane species in Central Europe, given its absence in lowland and alpine lakes.

15.
Inland Waters ; 7(1): 3-13, 2017 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-28649318

RESUMEN

Lakes in the Alps represent a considerable fraction of nutrient-poor lakes in Central Europe, with unique biodiversity and ecosystem properties. Although some individual lakes are well-studied, less knowledge is available on large-scale patterns essential to generalise the understanding of their functioning. Here, we aimed to describe crustacean zooplankton communities (Cladocera, Copepoda) and identify their environmental drivers in the pelagic zone of 54 oligotrophic lakes in the montane region of the Alps (400-1200 m) in Austria, Germany, and Switzerland, covering a spatial scale of 650 km. Moreover, we aimed to provide data on the distribution and ecological requirements of the North American invader Bytotrephes longimanus in its Central European native range. Communities were mainly dominated by widespread species typical of lowland habitats, and only a few true specialists of oligotrophic alpine lakes were present. The most frequent taxa were the Daphnia longispina complex and Eudiaptomus gracilis, with 48 and 45 occurrences, respectively. Species richness decreased with altitude and increased with lake area. The main structuring factors of community composition were chlorophyll a concentration and depth, which drove an apparent separation of mesotrophic and oligotrophic communities. Bytotrephes had 13 occurrences, showing a preference for deep oligotrophic lakes. Its presence was not coupled with lower crustacean species richness as it was repeatedly observed in North America. Additionally, it frequently co-occurred with the other large predatory cladoceran, Leptodora kindtii. B. longimanus might be considered a truly montane species in Central Europe, given its absence in lowland and alpine lakes.

16.
Limnologica ; 62: 38-46, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28572691

RESUMEN

Soda lakes and pans represent saline ecosystems with unique chemical composition, occurring on all continents. The purpose of this study was to identify and characterise the main environmental gradients and trophic state that prevail in the soda pans (n=84) of the Carpathian Basin in Central Europe. Underwater light conditions, dissolved organic matter, phosphorus and chlorophyll a were investigated in 84 pans during 2009-2010. Besides, water temperature was measured hourly with an automatic sensor throughout one year in a selected pan. The pans were very shallow (median depth: 15 cm), and their extremely high turbidity (Secchi depth median: 3 cm, min: 0.5 cm) was caused by high concentrations of inorganic suspended solids (median: 0.4 g L-1, max: 16 g L-1), which was the dominant (>50%) contributing factor to the vertical attenuation coefficient in 67 pans (80%). All pans were polyhumic (median DOC: 47 mg L-1), and total phosphorus concentration was also extremely high (median: 2 mg L-1, max: 32 mg L-1). The daily water temperature maximum (44 °C) and fluctuation maximum (28 °C) were extremely high during summertime. The combination of environmental boundaries: shallowness, daily water temperature fluctuation, intermittent hydroperiod, high turbidity, polyhumic organic carbon concentration, high alkalinity and hypertrophy represent a unique extreme aquatic ecosystem.

17.
Biol Conserv ; 209: 253-262, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28529346

RESUMEN

Considering the ongoing loss of aquatic habitats, anthropogenic ponds are gaining importance as substitute habitats. It is therefore important to assess their functioning in comparison to their natural precursors. Here we assess the biodiversity value of sodic bomb crater ponds by comparing their gamma diversity to that of natural reference habitats, astatic soda pans, and assess their importance on the landscape level by studying alpha and beta diversity. We studied aquatic organisms ranging from algae to vertebrates in a dense cluster of 54 sodic bomb crater ponds in Central Europe. Despite the overall small area of the pond cluster, gamma diversity was comparable to that found in surveys of natural habitats that encompassed much wider spatial and temporal scales. We also found a considerable number of species shared with reference habitats, indicating that these anthropogenic habitats function as important refuge sites for several species that are associated with the endangered soda pans. Moreover, we found a number of regionally or worldwide rare species. Among the components of beta diversity, species replacement dominated community assembly. Individual ponds contributed similarly to beta diversity in terms of replacement, being equally important for maintaining high gamma diversity and emphasising the role of the pond network rather than individual ponds. This pattern was seen in all studied groups. Bomb crater ponds therefore acted as important contributors to aquatic biodiversity. Considering the tremendous losses of ponds throughout Europe, anthropogenic ponds should be taken into consideration in nature conservation, especially when occurring in pond networks.

18.
Eur J Prev Cardiol ; 24(11): 1148-1156, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28438028

RESUMEN

Background Acute coronary syndrome is associated with platelet hyperactivity, which in its persistent form, promotes recurrent thrombotic events. Complex cardiac rehabilitation after acute coronary syndrome improves clinical outcome; however, its effect on platelet hyperactivity is unknown. Design and methods We enrolled 84 acute coronary syndrome patients on dual antiplatelet therapy, who underwent a new complex cardiac rehabilitation programme (NovaCord physiotherapy, lifestyle counselling, strict diet, stress management and regular coaching) and 51 control acute coronary syndrome patients with traditional cardiac rehabilitation. Platelet functionality was determined at enrolment and at three months follow-up by aggregometry, serum platelet-derived growth factor levels, total- and platelet-derived microvesicle counts (PMV; CD41a+/CD61+, CD62P+). Results Platelet aggregation parameters and platelet-derived growth factor levels were significantly decreased in the complex cardiac rehabilitation group at three months (1 µg/ml collagen, median (interquartile range): 22 (10-45) vs 14 (7.5-25.5)%, p = 0.0015; 2 µg/ml collagen: 36 (22-60) vs 26.5 (16-37)%, p = 0.0019; 1.25 µM adenosine-diphosphate: 4.5 (1-10) vs 1 (0-3)%, p = 0.0006; 5 µM adenosine-diphosphate: 27 (16-38) vs 22 (12-31)%, p = 0.0078; epinephrine: 33 (15-57) vs 27 (12-43)%, p = 0.01; platelet-derived growth factor: 434.6 (256.0-622.7) vs 224.8 (148.5-374.1) pg/ml, p = 0.0001). In contrast, these changes were absent or did not reach statistical significance in the traditional cardiac rehabilitation group. Platelet-derived microvesicle counts were significantly decreased in both groups, while total microvesicle count was significantly reduced only in the complex cardiac rehabilitation group (median (interquartile range): 3945.5 (2138-5661) vs 1739 (780-2303) count/µl; p = 0.0001). Conclusions Platelet hyperactivity three months after acute coronary syndrome significantly decreased in patients undergoing complex cardiac rehabilitation. Besides dual antiplatelet therapy, effective management and comprehensive control of cardiovascular risk factors might represent a new, non-pharmacological approach to influence platelet functionality.


Asunto(s)
Síndrome Coronario Agudo/rehabilitación , Plaquetas/fisiología , Rehabilitación Cardiaca/métodos , Dietoterapia/métodos , Estilo de Vida Saludable , Modalidades de Fisioterapia , Agregación Plaquetaria/fisiología , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Sobrevivientes/estadística & datos numéricos , Síndrome Coronario Agudo/sangre , Femenino , Estudios de Seguimiento , Humanos , Integrina alfa2/sangre , Integrina beta3/sangre , Masculino , Persona de Mediana Edad , Selectina-P/sangre , Pruebas de Función Plaquetaria , Estudios Prospectivos
19.
Clin Chim Acta ; 463: 138-144, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27794429

RESUMEN

The effect of invasive percutaneous coronary procedures on complement activation has not been elucidated. We enrolled stable angina patients with elective percutaneous coronary intervention (SA-PCI, n=24), diagnostic coronary angiography (CA, n=52) and 23 patients with ST segment elevation myocardial infarction and primary PCI (STEMI-PCI). Complement activation products (C1rC1sC1inh, C3bBbP and SC5b-9) were measured on admission, 6 and 24h after coronary procedures. The alternative pathway product, C3bBbP significantly and reversibly increased 6h after elective PCI (baseline: 7.81AU/ml, 6h: 16.09AU/ml, 24h: 4.27AU/ml, p<0.01, n=23) and diagnostic angiography (baseline: 6.13AU/ml, 6h: 12.08AU/ml, 24h: 5.4AU/ml, p<0.01, n=52). Six hour C3bBbP values correlated with post-procedural CK, creatinine level and the applied contrast material volume (r=0.41, r=0.4, r=0.3, p<0.05, respectively). In STEMI-PCI, baseline C3bBbP level was higher, compared to SA-PCI or CA patients (11.33AU/ml vs. 7.81AU/ml or 6.13AU/ml, p<0.001). Similarly, the terminal complex (SC5b-9) level was already elevated at baseline compared to SA-PCI group (3.49AU/ml vs. 1.87AU/ml, p=0.011). Complement pathway products did not increase further after primary PCI. Elective coronary procedures induced transient alternative complement pathway activation, influenced by the applied contrast volume. In STEMI, the alternative complement pathway is promptly activated during the atherothrombotic event and PCI itself had no further detectable effect.


Asunto(s)
Angina de Pecho/inmunología , Angina de Pecho/cirugía , Procedimientos Quirúrgicos Cardíacos , Activación de Complemento , Vía Alternativa del Complemento/inmunología , Infarto del Miocardio/inmunología , Infarto del Miocardio/cirugía , Enfermedad Aguda , Angina de Pecho/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre
20.
Ecography ; 39(8): 726-732, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28529408

RESUMEN

Directional dispersal by wind and other dispersal agents may generate spatial patterns in passively dispersing metacommunities which cannot be detected by classical eigenvector methods based on Euclidean distances. We analysed zooplankton communities (Rotifera, Cladocera, Copepoda) in a cluster of soda pans distributed over a short spatial scale of 18 km and tested explicitly for directional signals in their spatial configuration. The study area is exposed to a prevailing northwestern wind direction. By applying asymmetric eigenvector maps (AEM), we were able to identify corresponding directionality in the spatial structure of communities. Furthermore, the match between community composition and environmental conditions exhibited a spatial pattern consistent with the prevailing wind corridor, with best match found downwind the dominant wind direction. We also found that classical eigenvector methods based on Euclidean distances underestimated the role of spatial processes in our data. Our study furthermore shows that dispersal limitation may constrain community assembly in highly mobile organisms even at spatial scales below 5 km.

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