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Background After cranioplasty, in many cases a not negligible soft tissue defect remains in the temporozygomatical area, also referred to as a hollowing defect of the temple. Objective To assess the precise localization and volume of the hollowing defect, to optimize future cranioplasties. Methods CT data of patients who received craniectomy and conventional CAD cranioplasty in our institution between 2012 and 2018 were analyzed. CT datasets prior to craniectomy and after cranioplasty were subtracted to quantify the volume and localization of the defect. Results Out of 91 patients, 21 had suitable datasets. Five cases had good cosmetic results with no defect visible, 16 patients had an apparent hollowing defect. Their average defect volume was 5.0 cm3 ± 4.5 cm3. The defect localizations were in the area behind the zygomatic process and just below the superior temporal line, covering an area of app. 3x3 cm2. Surgical attempts of temporal muscle restoration were more often found in reports of good results (p Conclusion This work supplies evidence for the indication of a surgical corrective during cranioplasty in the small but cosmetically relevant area of the “frontozygomatic shadow”. Based on our 3D data analysis, future focused surgical strategies may obtain better aesthetical results here.

Excessive inputs of nitrogen from anthropogenic activities in watersheds can cause detrimental effects to aquatic ecosystems, but these effects can be difficult to determine based solely on nitrogen concentrations because of their temporal variability and the need to link human activities to ecological responses. Here, we (1) tested the use of stable isotopes of nitrogen (δ15N) and carbon (δ13C) in benthic organic matter (BOM) as proxies for isotope ratios of filter feeding bivalves in lakes and estuaries, which can be used as indicators but are harder to sample and often spatially sparse, and (2) evaluated if stable isotope ratios in benthic organic matter could be used to assess impacts from anthropogenic land development of watersheds. The δ15N in BOM isolated from surficial sediment (δ15NBOM) was significantly correlated with δ15N in filter feeding unionid mussels (Elliptio complanata, δ15NUN) from lakes and with hard-shell clams (Mercenaria mercenaria, δ15NMM) from estuaries. In lakes, δ13CBOM was significantly correlated with δ13CUN, but δ13CBOM was not significantly correlated with δ13CMM in estuaries. Values of δ15NBOM and δ15NUN were significantly and positively correlated with increasing amounts of impervious surface, urban land cover, and human populations in watersheds surrounding lakes. In estuaries, δ15NBOM was only significantly and positively correlated with greater percent impervious surface in the watersheds. Correlations of δ13CBOM in lakes and estuaries, δ13CUN, and δ13CMM with land use and human population were mostly non-significant or weak. Overall, these results show that δ15NBOM can serve as a proxy for δ15N of filter feeding bivalves in lakes and estuaries and is useful for assessing anthropogenic impacts on aquatic systems and resources. Our study area was limited in size, but our results support further studies to test the application of this sediment stable isotope-based technique for assessing and ranking aquatic resources across broad geographical areas.

Estimating the trophic position of predators in food webs using stable isotopes requires establishing a “baseline”, typically served by bivalves or snails. However, the frequent absence of such organisms in lakes leaves researchers in a difficult situation. Here we test the hypothesis that trophic position (TP) of largemouth bass (LB; Micropterus salmoides) in lakes can be estimated from δ15N of benthic organic material (BOM) in littoral surficial sediment. δ15NLB as a function of δ15NBOM was significant across 51 lakes with an R2 of 0.84, supporting our hypothesis. In a subset of six lakes, the mean TPLB did not differ significantly when calculated using baselines of δ15N in BOM, unionid mussels (UN), gastropods (SN), or from a stable isotope mixing model. In a subset of 26 lakes, mean TPLB calculated from δ15NBOM and δ15NUN baselines were not significantly different, but TPLB calculated using δ15NBOM was not significantly correlated with TPLB calculated using δ15NUN. Although δ15NBOM should not be used interchangeably with δ15NUN as a baseline for estimating TPLB, δ15NBOM can be useful as a separate baseline where estimates of fish TP are needed in all study lakes given that mussels are frequently absent and BOM is always available for collection.

Our understanding of how ecosystems function has changed from an equilibria-based view to one that recognizes the dynamic, fluctuating, nonlinear nature of aquatic systems. This current understanding requires that we manage systems for resilience. In this review, we examine how resilience has been defined, measured and applied in aquatic systems, and more broadly, in the socioecological systems in which they are embedded. Our review reveals the importance of managing stressors adversely impacting aquatic system resilience, as well as understanding the environmental and climatic cycles and changes impacting aquatic resources. Aquatic resilience may be enhanced by maintaining and enhancing habitat connectivity as well as functional redundancy and physical and biological diversity. Resilience in aquatic socioecological system may be enhanced by understanding and fostering linkages between the social and ecological subsystems, promoting equity among stakeholders, and understanding how the system is impacted by factors within and outside the area of immediate interest. Management for resilience requires implementation of adaptive and preferably collaborative management. Implementation of adaptive management for resilience will require an effective monitoring framework to detect key changes in the coupled socioecological system. Research is needed to (1) develop sensitive indicators and monitoring designs, (2) disentangle complex multi-scalar interactions and feedbacks, and (3) generalize lessons learned across aquatic ecosystems and apply them in new contexts.

1. Fatty acids are essential to macroinvertebrate growth and reproduction and can indicate food web structure and nutritional quality of basal resources. However, broad-scale examinations of how catchment land cover and associated stressors affect the proportions of fatty acids (FAs) in stream food webs are few. 2. Here, we: (1) examine relationships among proportions of FAs among benthic periphyton and macroinvertebrate collector/gatherers, shredders, and predators; and (2) test if relationships between periphytic and macroinvertebrate FAs were altered due to the intensity of urban development in catchments. 3. Proportions of the ≥20-C eicosapentaenoic acid (EPA 20:5ω3), arachidonic acid (ARA 20:4ω6), and docosahexaenoic acid (22:6ω3) indicated collector/gatherers had a diet richer in periphyton than in shredders, which had significantly lower proportions of these FAs. Collector/gatherers were in turn likely to be high-quality sources of ω3 and ≥ 20-C FAs for predators, which also had significantly greater EPA and ARA proportions than those in shredders. Linoleic (18:2ω6) and α-linolenic acid (18:3ω3) comprised the greatest proportions of FAs in shredders, which suggested a diet dominated by leaf litter and associated hyphomycetes. 4. As catchment urbanisation increased, proportions of total ω3 FAs and EPA in periphyton were significantly greater. This pattern also was seen through macroinvertebrate consumers and predators, given that proportions of these FAs in macroinvertebrates also were significantly correlated with factors associated with catchment urbanisation. The significant increase in total ω3 FAs and EPA proportions within shredders indicated that periphyton growth, and their FAs, increased on leaf litter, probably due to greater nutrient concentrations associated with catchment urbanisation. Proportions of total ω6 FAs in biota were not significantly correlated with factors associated with urban development, which could indicate that they were of sufficient abundance for consumers regardless of urban intensity or possible changes in their sources. 5. Our study provides an informative first step that identified notable differences in proportions of FAs among macroinvertebrates in urban streams and an increase in proportions of total ω3 FAs and EPA in periphyton, consumers, and predators as catchment urbanisation increases. Identifying how FA relationships within food webs change in response to catchment alterations and stressors could inform land use and management decisions by linking environmental changes to measures important to ecosystem outcomes.

Narragansett Bay is an urban estuary that historically has been impacted by long-term discharge of sanitary wastewater (WW) effluents. High-density water sampling was conducted in Narragansett Bay, RI, USA, in an effort to understand the distribution and behavior of sucralose, an artificial sweetener that has shown utility as a sanitary wastewater tracer. Water samples were collected at sixty-seven sites and analyzed for sucralose, whose performance was compared to other tracers present in wastewater effluents. Concentrations of sucralose were much higher than the other tracers measured, carbamazepine and caffeine, ranging from 18 to 3180 ng/L and corresponded well with salinity (r2 = 0.88), demonstrating conservative behavior throughout the Bay. Mapped interpolation data using an empirical bayesian kriging model clearly show the spatial trends of WW and how estuarine processes influence dilution and dispersion throughout the Bay. These findings provide further evidence of the efficacy of sucralose as a wastewater tracer in large urban estuaries where continuous high-volume discharge of WW occur.

Watershed integrity, the capacity of a watershed to support and maintain ecological processes essential to the sustainability of services provided to society, can be influenced by a range of landscape and in-stream factors. Ecological response data from four intensively monitored case study watersheds exhibiting a range of environmental conditions and landscape characteristics across the United States were used to evaluate the performance of a national level Index of Watershed Integrity (IWI) at regional and local watershed scales. Using Pearson’s correlation coefficient (r), and Spearman’s rank correlation coefficient (rs), response variables displayed highly significant relationships and were significantly correlated with IWI and ICI (Index of Catchment Integrity) values at all watersheds. Nitrogen concentration and flux-related watershed response metrics exhibited significantly strong negative correlations across case study watersheds, with absolute correlations (|r|) ranging from 0.48 to 0.97 for IWI values, and 0.31 to 0.96 for ICI values. Nitrogen-stable isotope ratios measured in chironomids and periphyton from streams and benthic organic matter from lake sediments also demonstrated strong negative correlations with IWI values, with |r| ranging from 0.47 to 0.92, and 0.35 to 0.89 for correlations with ICI values. This evaluation of the performance of national watershed and catchment integrity metrics and their strong relationship with site level responses provides weight-of-evidence support for their use in state, local and regionally focused applications.

Watershed development and anthropogenic sources of nitrogen are among leading causes of negative impacts to aquatic ecosystems around the world. The δ15N of aquatic biota can be used as indicators of anthropogenic sources of nitrogen enriched in 15N, but this mostly has been done at small spatial extents or to document effects of point sources. In this study, we sampled 77 sites along a forest to urban land cover gradient to examine food webs and the use of δ15N of periphyton and macroinvertebrate functional feeding groups (FFGs) as indicators of watershed development and nitrogen effects on streams. Functional feeding groups had low δ15N variability among taxa within sites. Mean absolute differences between individual taxa and their respective site FFG means were < 0.55‰, whereas site means of δ15N of FFGs had ranges of approximately 7-12‰ among sites. The δ15N of periphyton and macroinvertebrate FFGs distinguished least disturbed streams from those with greater watershed urbanization, and they were strongly correlated with increasing nitrogen concentrations and watershed impervious cover. Nonmetric multidimensional scaling, using δ15N of taxa, showed that changes in macroinvertebrate assemblages as a whole were associated with forest-to-urban and increasing nitrogen gradients. Assuming an average +3.4‰ per trophic level increase, δ15N of biota indicated that detrital pathways likely were important to food web structure, even in streams with highly developed watersheds. We used periphyton and macroinvertebrate FFG δ15N to identify possible management goals that can inform decisions affecting nutrients and watershed land use. Overall, the δ15N of periphyton and macroinvertebrates were strong indicators of watershed urban development effects on stream ecosystems, and thus, also could make them useful for quantifying the effectiveness of nitrogen, stream, and watershed management efforts.

The radiographic finding of gastric emphysema with portal venous gas is classically an ominous finding, associated with a high rate of mortality. Although classically the case, this imaging finding must be quickly correlated with the overall clinical picture, allowing for the essential differentiation between the highly lethal emphysematous gastritis and the much more benign gastric emphysema, each of which has drastically different management strategies. We report a case of gastric emphysema with portal venous gas likely attributable to a gastric outlet obstruction and gastric mucosal defect in a 17-year-old girl with a chief complaint of syncope that was diagnosed in the emergency department and treated conservatively.

Watershed management and policies affecting downstream ecosystems benefit from identifying relationships between land cover and water quality. However, different data sources can create dissimilarities in land cover estimates and models that characterize ecosystem responses. We used a spatially balanced stream study (1) to effectively sample development and urban stressor gradients while representing the extent of a large coastal watershed (>4400 km(2)), (2) to document differences between estimates of watershed land cover using 30-m resolution national land cover database (NLCD) and

The cnidarian freshwater polyp Hydra sp. exhibits an unparalleled regeneration capacity in the animal kingdom. Using an integrative transcriptomic and stable isotope labeling by amino acids in cell culture proteomic/phosphoproteomic approach, we studied stem cell-based regeneration in Hydra polyps. As major contributors to head regeneration, we identified diverse signaling pathways adopted for the regeneration response as well as enriched novel genes. Our global analysis reveals two distinct molecular cascades: an early injury response and a subsequent, signaling driven patterning of the regenerating tissue. A key factor of the initial injury response is a general stabilization of proteins and a net upregulation of transcripts, which is followed by a subsequent activation cascade of signaling molecules including Wnts and transforming growth factor (TGF) beta-related factors. We observed moderate overlap between the factors contributing to proteomic and transcriptomic responses suggesting a decoupled regulation between the transcriptional and translational levels. Our data also indicate that interstitial stem cells and their derivatives (e.g., neurons) have no major role in Hydra head regeneration. Remarkably, we found an enrichment of evolutionarily more recent genes in the early regeneration response, whereas conserved genes are more enriched in the late phase. In addition, genes specific to the early injury response were enriched in transposon insertions. Genetic dynamicity and taxon-specific factors might therefore play a hitherto underestimated role in Hydra regeneration.

Recently, three ion channel subunits of the degenerin (DEG)/epithelial Na(+) channel (ENaC) gene family have been cloned from the freshwater polyp Hydra magnipapillata, the Hydra Na(+) channels (HyNaCs) 2-4. Two of them, HyNaC2 and HyNaC3, co-assemble to form an ion channel that is gated by the neuropeptides Hydra-RFamides I and II. The HyNaC2/3 channel is so far the only cloned ionotropic receptor from cnidarians and, together with the related ionotropic receptor FMRFamide-activated Na(+) channel (FaNaC) from snails, the only known peptide-gated ionotropic receptor. The HyNaC2/3 channel has pore properties, like a low Na(+) selectivity and a low amiloride affinity, that are different from other channels of the DEG/ENaC gene family, suggesting that a component of the native Hydra channel might still be lacking. Here, we report the cloning of a new ion channel subunit from Hydra, HyNaC5. The new subunit is closely related to HyNaC2 and -3 and co-localizes with HyNaC2 and -3 to the base of the tentacles. Coexpression in Xenopus oocytes of HyNaC5 with HyNaC2 and -3 largely increases current amplitude after peptide stimulation and affinity of the channel to Hydra-RFamides I and II. Moreover, the HyNaC2/3/5 channel has altered pore properties and amiloride affinity, more similarly to other DEG/ENaC channels. Collectively, our results suggest that the three homologous subunits HyNaC2, -3, and -5 form a peptide-gated ion channel in Hydra that could contribute to fast synaptic transmission.

We used recent developments in theoretical population ecology to construct basic models of common loon (Gavia immer) demography and population dynamics. We parameterized these models using existing survival estimates and data from long-term monitoring of loon productivity and abundance. Our models include deterministic, 2-stage, density-independent matrix models, yielding population growth-rate estimates (λ) of 0.99 and 1.01 for intensively studied populations in our Wisconsin, USA, and New Hampshire, USA, study areas, respectively. Perturbation analysis of these models indicated that estimated growth rate is extremely sensitive to adult survival, as expected for this long-lived species. Also, we examined 20 years of count data for the 2 areas and evaluated support for a set of count-based models of population growth. We detected no temporal trend in Wisconsin, which would be consistent with fluctuation around an average equilibrium state but could also result from data limitations. For New Hampshire, the model set included varying formulations of density dependence and partitioning of stochasticity that were enabled by the annual sampling resolution. The best model for New Hampshire included density regulation of population growth and, along with the demographic analyses for both areas, provided insight into the possible importance of breeding habitat availability and the abundance of nonbreeding adults. Based on these results, we recommend that conservation organizations include nonbreeder abundance in common loon monitoring efforts and that additional emphasis be placed on identifying and managing human influences on adult loon survival.

The Cassini Imaging Science Subsystem (ISS) acquired 377 high-resolution images ( http://ciclops.org/maps ).

Chemical transmitters are either low molecular weight molecules or neuropeptides. As a general rule, neuropeptides activate only slow metabotropic receptors. To date, only one exception to this rule is known, the FMRFamide-activated Na(+) channel (FaNaC) from snails. Until now FaNaC has been regarded as a curiosity, and it was not known whether peptide-gated ionotropic receptors are also present in other animal groups. Nervous systems first evolved in cnidarians, which extensively use neuropeptides. Here we report cloning from the freshwater cnidarian Hydra of a novel ion channel (Hydra sodium channel, HyNaC) that is directly gated by the neuropeptides Hydra-RFamides I and II and is related to FaNaC. The cells expressing HyNaC localize to the base of the tentacles, adjacent to the neurons producing the Hydra-RFamides, suggesting that the peptides are the natural ligands for this channel. Our results suggest that neuropeptides were already used for fast transmission in ancient nervous systems.

The goal of this study was to evaluate human epiphyseal chondroprogenitor cells (ECPs) as a potential new cell source for cartilage regeneration. ECPs were compared to human bone marrow stromal cells (MSCs) and human adult articular chondrocytes (ACs) for their chondrogenic potential and phenotypic stability in vitro and in vivo. The cells were seeded in Optimaix-3D scaffolds at 5 × 10

The development of effective gene-therapeutic applications for cardiovascular disorders is in part limited by the lack of appropriate delivery systems. In an attempt to overcome this deficiency, we investigated the ability of baculoviral vectors to transduce human cardiovascular cells, for which data are missing in literature. Additionally, baculovirus ability to transduce target cells was compared to that of an adenoviral vector, a well characterized and widely used viral vector. Transduction experiments, performed using baculo/adenoviral vectors expressing the enhanced green fluorescence protein, revealed that, under the experimental condition considered, baculoviruses but not adenoviruses efficiently transduce human coronary smooth muscle cells (hCSMC); an opposite behavior was noticed for human coronary endothelial cells (hCEC). Thus, baculoviral vectors are potentially indicated as transfer system in the treatment of coronary restenosis, where growth inhibitory genes should reach hCSMC but not hCEC. When used to transduce human cardiomyocytes and fibroblasts, both vectors behaved similarly. Finally, studies on cellular DNA replication revealed a more prolonged and pronounced negative effect on cells transduced by adenoviral compared to baculoviral vectors. Our data indicate that baculoviruses represent an attractive alternative to adenoviruses as transfer vectors in cardiovascular cells and that baculovirus have the potential to be used as gene transfer system in cardiovascular diseases such as restenosis.

We obtained a water sample containing broken pieces of a tropical coral reef decor that was suspected of causing fish toxicity in a major aquarium. A toxicity identification and evaluation (TIE) was performed using three species: a mysid shrimp, Americamysis bahia; inland silverside Menidia beryllina; and an amphipod, Ampelisca abdita. Initial tests indicated that only the shrimp was sensitive to the unknown toxicant. The first phase of the TIE indicated that the toxicity to the shrimp could be eliminated by either the addition of EDTA or manipulation of the cation exchange column. Elevated concentrations of Cd were detected by inductively coupled plasma analysis, and metal toxicity was confirmed when the cation exchange column treatment successfully isolated the toxic metal. Analysis of affected fish tissue indicated Cd levels ranging from less than 0.3 ng/g in the muscle to 200 μg/g in the liver. This study demonstrates a unique application of TIE methods to diagnose toxicity problems in aquari...

Die Restenose bleibt die wesentliche Limitierung verschiedener interventioneller Therapiemassnahmen, auch der Stentimplantation. Dies erklart das unverandert grose Interesse an ihren zugrundeliegenden Pathogenesemechanismen und -faktoren. Ziel der vorliegenden Arbeit war es, Lokalisation und Expressionsmaxima von Bcl-2, einem zentralen anti-apoptotischen Protoonkogen, und von Hitzeschockprotein 47 (HSP47), einem Marker fruher Kollagensynthese, im Kontext mit der Formierung hyperplastischer Neointima und parallelen transmuralen Umbauprozessen nach Angioplastie zu untersuchen. 0, 4, 24 und 48 Stunden, 4, 7 und 14 Tage nach Ballontrauma wurden am Modell der A. carotis der Ratte einzelne Gefasswandkompartimente hinsichtlich Flache, Zelldichte sowie Bcl-2- bzw. HSP47-Expression (immun-)histochemisch und morphometrisch evaluiert, erganzt durch Elektronenmikroskopie (TEM). Neointimale Zellakkumulation war bereits 4 Tage nach Angioplastie nachweisbar, ausgewiesen durch Adhasion luminaler Zellen an die Lamina elastica interna, assoziiert mit maximaler Bcl-2- sowie HSP47-Expression von 49% bzw. 41% aller gezahlten Zellen. Mit zunehmender Neointima demarkierte sich eine lumennahe Pravalenz beider Zieldeterminanten mit abnehmender Expression zu basalen Arealen. In der Media fand sich eine temporare, lediglich 48 Stunden nach Trauma signifikant verminderte Zelldichte. Die konstitutive HSP47-Expression der Media war im gesamten Beobachtungszeitraum konstant, wahrend fur Bcl-2 nach Angioplastie wenige Signale nachweisbar waren mit Maximalwerten von 3% am Tag 2 und 5% am Tag 14. Die Adventitia wies eine transiente strukturelle Zweiteilung zwischen Tag 4 und 7 auf mit einer inneren, extrem zellarmen Schicht und einer auseren Schicht bei sehr hoher Zelldichte sowie ausgepragter Neovaskularisation. In dieser auseren Adventitia waren hohe Signaldichten von Bcl-2 und HSP47 bis zu 29% bzw. 57% nachweisbar. Komplementare TEM-Untersuchungen ergaben keine Hinweise auf die transmurale Migration adventitialer Zellen und stutzen somit eine fruhe Neointimaformierung durch luminale Zellrekrutierung bei hoher Co-Expression des anti-apoptotischen Bcl-2 und des Matrix-generierenden HSP47 als wichtige Uberlebensfaktoren. Klinische Implikationen dieser Befunde konnten in der Integration befristet pro-apoptotischer Substanzen zur Restenosepravention, z.B. in beschichteten Stents, liegen.

Ten-day acute mortality of the benthic amphipod Ampelisca abdita is used in a number of regulatory, research, and monitoring programs to evaluate chemical contamination of marine sediments. Although this endpoint has proven to be valuable for characterizing the relative toxicities of sediments, the significance of acute mortality with respect to population viability has not yet been established. In this study, population modeling along with empirical extrapolation were used to describe a relationship between acute mortality and population-level response of A. abdita. The research involved the performance of a standard 10-d sediment toxicity bioassay and a 70-d full life-cycle chronic population (including reproduction) bioassay exposing A. abdita to sediments spiked with concentrations of the divalent metal cadmium (normalized to acid volatile sulfide) expected to produce a range of biological effects. These data provided age-specific schedules of survival and fecundity that were used to parameterize an age-classified projection matrix model for A. abdita. Measured exposure data and population growth rate estimates, obtained using the demographic information collected during the 70-d assay, were used to develop exposure—response models. These data were also used to develop an empirical relationship between population growth rate (λ) and acute mortality. This relationship describes how acute data may be used to predict concentrations that produce population-level effects. Model manipulations permit extrapolation of early life-stage mortality (the acute endpoint) to changes in population growth rate. These relationships were used to evaluate a range of ecologically acceptable acute mortality for A. abdita.

The identification of toxicants affecting aquatic benthic systems is critical to sound assessment and management of our nation's waterways. Identification of toxicants can be useful in designing effective sediment remediation plans and reasonable options for sediment disposal. Knowledge of which contaminants affect benthic systems allows managers to link pollution to specific dischargers and prevent further release of toxicant(s). In addition, identification of major causes of toxicity in sediments may guide programs such as those developing environmental sediment guidelines and registering pesticides, while knowledge of the causes of toxicity which drive ecological changes such as shifts in benthic community structure would be useful in performing ecological risk assessments. To this end, the US Environmental Protection Agency has developed tools (toxicity identification and evaluation (TIE) methods) that allow investigators to characterize and identify chemicals causing acute toxicity in sediments and dredged materials. To date, most sediment TIEs have been performed on interstitial waters. Preliminary evidence from the use of interstitial water TIEs reveals certain patterns in causes of sediment toxicity. First, among all sediments tested, there is no one predominant cause of toxicity; metals, organics, and ammonia play approximately equal roles in causing toxicity. Second, within a single sediment there are multiple causes of toxicity detected; not just one chemical class is active. Third, the role of ammonia is very prominent in these interstitial waters. Finally, if sediments are divided into marine or freshwater, TIEs perforMed on interstitial waters from freshwater sediments indicate a variety of toxicants in fairly equal proportions, while TIEs performed on interstitial waters from marine sediments have identified only ammonia and organics as toxicants, with metals playing a minor role. Preliminary evidence from whole sediment TIEs indicates that organic compounds play a major role in the toxicity of marine sediments, with almost no evidence for either metal or ammonia toxicity. However, interpretation of these results may be skewed because only a small number of interstitial water (n = 13) and whole sediment (n = 5) TIEs have been completed. These trends may change as more data are collected.

Background It is generally the case that fast transmission at neural synapses is mediated by small molecule neurotransmitters. The simple nervous system of the cnidarian Hydra, however, contains a large repertoire of neuropeptides and it has been suggested that neuropeptides are the principal transmitters of Hydra. An ion channel directly gated by Hydra-RFamide neuropeptides has indeed been identified in Hydra – the Hydra Na+ channel (HyNaC) 2/3/5, which is expressed at the oral side of the tentacle base. Hydra-RFamides are more widely expressed, however, being found in neurons of the head and peduncle region. Here, we explore whether further peptide-gated HyNaCs exist, where in the animal they are expressed, and whether they are all gated by Hydra-RFamides. Results We report molecular cloning of seven new HyNaC subunits – HyNaC6 to HyNaC12, all of which are members of the DEG/ENaC gene family. In Xenopus oocytes, these subunits assemble together with the four already known subunits into thirteen different ion channels that are directly gated by Hydra-RFamide neuropeptides with high affinity (up to 40 nM). In situ hybridization suggests that HyNaCs are expressed in epitheliomuscular cells at the oral and the aboral side of the tentacle base and at the peduncle. Moreover, diminazene, an inhibitor of HyNaCs, delayed tentacle movement in live Hydra. Conclusions Our results show that Hydra has a large variety of peptide-gated ion channels that are activated by a restricted number of related neuropeptides. The existence and expression pattern of these channels, and behavioral effects induced by channel blockers, suggests that Hydra co-opted neuropeptides for fast neuromuscular transmission. Electronic supplementary material The online version of this article (doi:10.1186/s12915-014-0084-2) contains supplementary material, which is available to authorized users.

Animal evolution is closely linked to the emergence of the nervous system. At present it is unknown how the basic mechanisms of neural induction and formation of central nervous systems evolved. We addressed this question in Nematostella vectensis, a member of cnidarians, the ancient sister group of bilaterians. We found that β-catenin signalling is crucial for the early induction of the embryonic nervous system. β-Catenin activity at the blastopore induces specific neurogenic genes required for development of the oral nervous system. β-Catenin signalling induces also Bmp signalling, which, at later larval stages, becomes indispensible for the maintenance and asymmetric patterning of the oral nervous system along the primary and secondary (directive) axes. We hypothesize that the consecutive and functionally linked involvement of β-catenin and Bmp signalling in the formation of the cnidarian oral nervous system reflects an ancestral mechanism that evolved before the cnidarian/bilaterian split., The bilaterian central nervous system is thought to have evolved from a cnidarian-like ancestor, but the mechanisms of neural induction in cnidarians are largely unknown. Here the authors study the cnidarian Nematostella vectensis and show that β-catenin signalling is crucial for the early induction of its embryonic nervous system, suggesting evolutionary roots for this pathway.

The Hydra Sodium Channel (HyNaC), a member of the DEG/ENaC ion channel family, is a peptide gated cation channel from the fresh water polyp Hydra magnipapillata. Four HyNaC subunits, HyNaC2 - HyNaC5, have already been characterized. It has been shown that HyNaCs 2, 3 and 5 assemble into a functional heterotrimeric channel, HyNaC2/3/5, which is activated with high affinity (EC50 ∼3.5 µM) by the endogenous neuropeptide Hydra-RFamide I.Here we report cloning of a new HyNaC subunit, HyNaC7. When expressed heterologously with HyNaC2 and 3, HyNaC7 increases apparent peptide affinity 20-40 times compared with HyNaC2/3/5 (EC50 ∼0.2 µM). Like HyNaC2/3/5, HyNaC2/3/7 is an unselective cation channel with a high calcium conductance and low apparent affinity for amiloride.By systematically swapping domains between HyNaC5 and HyNaC7 and functionally characterizing resulting chimeras, we identified the second transmembrane domain (TM2) and adjacent amino acids, located upstream as well as downstream of TM2, that determined the higher peptide affinity of HyNaC2/3/7. Currently, we investigate the influence of individual amino acids for ligand affinity.Together, our results show, that TM2 and C-terminal as well as N-terminal adjacent amino acids determine differences in ligand binding affinity of HyNaC2/3/7 and HyNaC2/3/5.

Toxicity identification evaluation (TIE) methods are being developed for use with whole sediments. Although a phase I TIE method has been developed to characterize ammonia toxicity in aqueous samples using the marine macroalga Ulva lactuca, the relationship between amphipod and mysid mortality and uptake by U. lactuca of bedded sediment ammonia had not been explored. Additionally, it was not known how interactions in whole sediments between metal and organic contaminants with U. lactuca and ammonia would affect TIE interpretation. The current study showed that ammonia toxicity to amphipods and mysids was reduced significantly in marine sediments in the presence of U. lactuca. The alga slightly affected metal concentrations but did not alter the concentration of organic contaminants in either overlying or interstitial waters. Conversely, ammonia uptake by U. lactuca was not affected by the presence of metal or organic contaminants in the sediments. When used with other TIE manipulations, U. lactuca can be utilized in a whole-sediment, phase I TIE to remove toxicity due to ammonia.

Proliferation of vascular smooth muscle cells is generally accepted as a key event in the development of restenosis following percutaneous transluminal angioplasty. To prevent human restenosis, we have designed a molecular strategy based on hammerhead ribozymes targeted against the mRNA of cyclin E and E2F1, two proteins relevant in cell cycle progression whose regulation is interconnected by a positive feedback loop. Following the identification of accessible ribozyme target sites by RNase H mapping, several hammerhead ribozymes were generated that cleave with comparable efficiency two different splice forms of cyclin E mRNA and the full-length and a truncated form of E2F1 RNA, respectively. The most active ribozymes were tested in vitro under single-turnover conditions yielding k(react)/K(m) ratios between 36 and 73 x 10(4) M(-1) min(-1), which places them in the top range ribozymes targeted against long and structured substrates. In addition, we show that the most active ribozyme selected in vitro reduces specifically and significantly (p < 0.0028) proliferation of cultured human vascular smooth muscle cells (VSMC).

An age-classified projection matrix model has beendeveloped to extrapolate the chronic (28–35 d) demographic responses of Americamysis bahia (formerly Mysidopsis bahia) to population-level response. This study was conducted to evaluate the efficacy of this model for predicting the population behavior of A. bahia held (for more than three generations) under controlled laboratory exposure conditions. The research involved the performance of a standard life-cycle test and a multigenerational (greater than three mysid generations, 55 d) assay using A. bahia to experimentally evaluate model predictions regarding population-level risks of chemical exposure. The organic compound para-nonylphenol was chosen as the chemical stressor in these assays. This compound is a ubiquitous contaminant and suspected endocrine disruptor. Utilizing data obtained during the standard life-cycle test, aggregate estimates of population growth rate (λ) and measured p-nonylphenol concentration were used to develop an exposure-response model of population-level effects. These estimates provided the basis of predictions for the long-term dynamics of mysid populations exposed to p-nonylphenol. The veracity of the mysid population model was evaluated through quantitative comparisons of model predictions based on the life-cycle test with dynamics of the experimental populations (multigenerational assay results). The results indicate that the population model was able to project within a few micrograms per liter the concentration where population-level effects would begin to occur (projected 16 μg/L from the model vs measured 19 μg/L from the multigenerational assay).

We investigated polymorphisms in the variable number of tandem repeat polymorphisms (VNTR) regions of the ACAN gene in 154 patients with pectus excavatum that required surgery. To our knowledge, this is the first study to examine correlation of a functional VNTR genotype of cartilage with pectus excavatum. Patients, non-affected family members, and controls were genotyped by PCR and the number of VNTRs identified. We observed that patients had significantly more 27 repeats, and significantly less 25 repeats, than controls and parents. We examined VNTRs with severity of disorder and found no correlation between ACAN genotype, repeat numbers, and severity. Subgroups in the pectus population were observed. There were a number of unique differences in these subgroups, especially in patients with a Marfan clinical phenotype, where there was a correlation of increased number of VNTRs with phenotype. Conversely, in the affected females, there was an inverse correlation between ACAN VNTRs and gender. Females also tended to present with a more severe phenotype compared to males. This is the first description of genetic polymorphisms in a candidate gene for pectus excavatum. Overall, there are observed associations between the VNTR regions of ACAN, a potential candidate gene, with pectus excavatum.

A multiagency effort is underway to develop whole sediment toxicity identification evaluation (TIE) methods. Whole sediment TIE methods will be critical tools for characterizing toxicity at hazardous waste sites (e.g., Superfund sites) and in the conduct of environmental risk assessments. The research approach is based on the predominance of three classes of toxicants in sediments: ammonia, nonpolar organic chemicals, and metals. Here we describe a procedure for characterizing acute toxicity caused by metals in whole marine sediments. The procedure involves adding a chelating resin to sediments, resulting in the sequestration of bioavailable metal while not stressing testing organisms. Within the testing chambers, the presence of resin resulted in statistically significant reductions in the overlying and interstitial water concentrations of five metals (cadmium, copper, nickel, lead, and zinc) generally by factors of 40 and 200. Toxicity to both the amphipod Ampelisca abdita and mysid Americamysis bahia (formerly Mysidopsis bahia) of sediments spiked with the five metals was decreased by approximately a factor of four when resin was present. While very effective at reducing the concentrations and toxicity of metals, the resin has only minor ameliorative effects on the toxicity of ammonia and a representative nonpolar toxicant (Endosulfan). Resin and accumulated metal were easily isolated from the testing system following exposures allowing for the initiation of phase II TIE (identification) procedures. This procedure using the addition of a chelating resin provides an approach for determining the importance of metals to the toxicity of marine sediments. Work is continuing to validate the method with environmentally contaminated sediments.

The7-d test measuring survival, growth, and fecundity of Americamysis bahia (formerly Mysidopsis bahia) was developed for estimating the chronic toxicity of effluents and associated receiving waters for National Pollutant Discharge Elimination System permits. Currently, this test and its derivatives are also used in toxicity identification evaluation (TIE), risk assessment, and other applications. To evaluate the relative sensitivity of three measurement endpoints (survival, growth, and fecundity), we analyzed results from 115 tests with effluents, organic or inorganic chemicals, and receiving waters suspected of being toxic. Controls for 78 of these (68%) achieved acceptable survival and growth. Fifty of these 78 tests (64%, i.e., 43% of the total tests) also achieved acceptable control fecundity. In the 47 tests with significant effects, survival was the most sensitive response in 57%, fecundity in 30%, and growth in 30%. There was little duplication in responses. Improving pretest holding conditions by decreasing the maximum density from ∼20 to 10 animals/L and increasing the temperature from ∼26°C to a range of 26 to 27°C improved the growth and fecundity in controls. Although the percentage of tests achieving acceptable control survival (>80%) and growth (>0.20 mg) decreased from 93 to 86%, the percentage achieving acceptable fecundity in controls (>50%) increased from 60 to 97%. Seasonal differences in fecundity were detected among control groups. Although variable, fecundity is often the most sensitive measure of response. The 7-d mysid test estimates the chronic toxicity of effluents most effectively when all three endpoints are used.

Ulva lactuca (sea lettuce) is a cosmopolitan marine attached green seaweed capable of sequestering high environmental levels of ammonia. Ammonia can be acutely toxic to marine organisms and is often found in dredged sediments from highly industrial areas or from areas with high carbon inputs. For the purposes of dredged sediment disposal as well as in determining causes of toxicity in complex mixtures, it is important to distinguish ammonia toxicity from the toxicity of other compounds. The use of U. lactuca to selectively remove ammonia from waters and sediments as part of a toxicity identification and evaluation (TIE) procedure was evaluated. Ulva lactuca lowered concentrations of total ammonia from 75 to 17 mg/L in

Entry into mitosis is accompanied by a global repression of transcription. To investigate the molecular mechanisms which shut-down rRNA synthesis during mitosis, we have compared RNA polymerase I (Pol I) transcription in extracts from asynchronous and mitotic HeLa cells. We show by several experimental approaches that phosphorylation by cdc2/cyclin B inactivates the TBP-containing factor SL1 and thus abrogates Pol I transcription during mitosis. This finding links the cell's cycle with the transcriptional activity of Pol I and suggests a common mechanism for mitotic silencing of all three classes of nuclear RNA polymerases, i.e. reversible inactivation of the respective TBP-TAF complexes by (a) mitotic kinase(s).

Phototoxicity resulting from photoactivated polycyclic aromatic hydrocarbons (PAHs) has been reported in the literature for a variety of freshwater organisms. The magnitude of increase in PAH toxicity often exceeds a factor of 100. In the marine environment phototoxicity to marine organisms has not been reported for individual or complex mixtures of PAHs. In this study, larvae and juveniles of the bivalve, Mulinia lateralis, and juveniles of the mysid shrimp, Mysidopsis bahia, were exposed to individual known phototoxic PAHs (anthracene, fluoranthene, pyrene), as well as the water-accommodated fractions of several petroleum products (Fuel Oil #2, Arabian Light Crude, Prudhoe Bay Crude, Fuel Oil #6) containing PAHs. Phototoxicity of individual PAHs was 12 to >50,000 times that of conventional toxicity. Three of the petroleum products demonstrated phototoxicity while the lightest product, Fuel Oil #2, was not phototoxic at the concentrations tested. The phototoxicity of petroleum products appears to be dependent on the composition and concentrations of phototoxic PAHs present: lighter oils have fewer multiple aromatic ring, phototoxic compounds while heavier oils have higher levels of these types of molecules. This study shows that phototoxicity can occur in marine waters to marine species. Further, the occurrence of oil in marine waters presents the additional risk of phototoxicity not routinely assessed for during oil spills.

In phase I of a standard toxicity identification evaluation (TIE) six manipulations are used to characterize toxicity. The ethylenediaminetetraacetic acid addition manipulation is most often used to indicate toxicity caused by divalent metals. An alternative approach for characterizing/identifying metal toxicity is the use of cation-exchange chromatography. In this study, five cation-exchange media were compared to develop a method for using cation-exchange chromatography as part of a marine TIE. To be considered useful the cation-exchange media must meet the following criteria: (1) consistently (with minimal variability) extract and elute toxic concentrations of a mixture of metals spiked into seawater, (2) demonstrate negligible blank acute toxicity, and (3) function effectively with environmental samples. Two solid-phase extraction media met the criteria: Supelco's LC-WCX column and Alltech's Extract-Clean IC-Chelate column. In general, these columns were able to remove 80 to 100% of five metals (Cd, Cu, Ni, Pb, Zn) from spiked seawater, and 85 to 100% of metals could be eluted back into solution (except copper for which recovery was 65–75%). Columns functioned effectively with seawater spiked with metals concentrations approaching 600 μg/L and showed low intercolumn variability (coefficient of variation = 1.0–14%). For actual environmental samples, once column breakthrough was assessed, both columns reduced toxicity and metal concentrations in postcolumn samples. Further, reconstituted column eluates were as toxic as whole samples. The methodology described can be used to assist in the TIE characterization and identification of toxic metals in environmental samples.

New Bedford Harbor (NBH) is a marine Superfund site contaminated with high concentrations of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and metals. Experiments were conducted to determine the causal toxic agent(s) in pore waters from New Bedford Harbor sediments to amphipods and mysid shrimp. Chemical manipulations to characterize toxicity revealed that pore-water toxicity was organic in nature. Fractionation and subsequent mass spectral identification of peaks in the toxic fraction indicated that PCBs, PAHs, and unknown compounds were present. Comparisons of PAH LC50s and PAH concentrations in this fraction indicated that the toxicity was not due to PAHs because the PAH concentrations were much lower than the reported PAH LC50s. One unknown peak was positively identified as bis(2-ethylhexyl) phthalate, and the other tentatively identified as pyrazole. Toxicity tests and comparison of toxicity in the blank and toxic fractions eliminated the two “unknowns” as toxic causal agents. We determined the range of PCB LC50s to fall between 10 and 110 ppb for Mysidopsis bahia and Ampelisca abdita. Concentrations of PCBs for the toxic fractions ranged from 12 to 27 ppb. This range falls within our observed PCB LC50s for M. bahia and A. abdita. Based upon these PCB concentrations, we concluded that PCBs were the acute toxic agents in NBH pore waters. Other compounds in the toxic fractions, or compounds that coeluted and were undistinguished from PCBs had minor contributions to the measured toxicity.

Toxicity Identification Evaluation (TIE) methods have proven very useful in characterizing, identifying and confirming toxicants in environmental samples. This report describes the characterization of toxicants present in two effluents, industrial and municipal, discharged into the marine environment. A toxicity characterization consists of dividing an effluent sample into several relatively unique chemical fractions. Manipulations used to generate these fractions include aeration, filtration, chelation, oxidant reduction, reverse phase chromatography, and graduated pH adjustments. Marine toxicity tests used include mysids (Mysidopsis bahia), fish (Menidia beryllina and Cyprinodon variegatus), macroalga (Champia parvula) and sea urchins (Arbacia punctulata). Results of this TIE demonstrated that both effluents contained toxicity predominantly due to metals and organic contaminants. Ammonia toxicity in the municipal effluent was sample dependent. This study illustrates that the use of marine toxicity tests, TIE procedures and historical data can be combined to better understand the nature of toxicity discharged to the marine environment.

The nucleolar factor UBF is phosphorylated by casein kinase II (CKII) at serine residues within the C-terminal acidic domain which is required for transcription activation. To investigate the biological significance of UBF modification, we have compared the trans-activating properties of cellular UBF and recombinant UBF expressed in Escherichia coli. Using a variety of assays we demonstrate that unphosphorylated UBF is transcriptionally inactive and has to be phosphorylated at multiple sites to stimulate transcription. Examination of cDNA mutants in which the serine residues within the C-terminal domain were altered by site-directed mutagenesis demonstrates that CKII-mediated phosphorylations of UBF contribute to, but are not sufficient for, transcriptional activation. Besides CKII, other cellular protein kinases phosphorylate UBF at distinct sites in a growth-dependent manner. The marked differences in the tryptic peptide maps of UBF from growing and serum-starved cells suggest that alterations in the degree of UBF phosphorylation may modulate rRNA synthetic activity in response to extracellular signals.

Common Loon (Gavia immer) is considered an emblematic and ecologically important example of aquatic-dependent wildlife in North America. The northern breeding range of Common Loon has contracted over the last century as a result of habitat degradation from human disturbance and lakeshore development. We focused on the state of New Hampshire, USA, where a long-term monitoring program conducted by the Loon Preservation Committee has been collecting biological data on Common Loon since 1976. The Common Loon population in New Hampshire is distributed throughout the state across a wide range of lake-specific habitats, water quality conditions, and levels of human disturbance. We used a multiscale approach to evaluate the association of Common Loon and breeding habitat within three natural physiographic ecoregions of New Hampshire. These multiple scales reflect Common Loon-specific extents such as territories, home ranges, and lake-landscape influences. We developed ecoregional multiscale models and compared them to single-scale models to evaluate model performance in distinguishing Common Loon breeding habitat. Based on information-theoretic criteria, there is empirical support for both multiscale and single-scale models across all three ecoregions, warranting a model-averaging approach. Our results suggest that the Common Loon responds to both ecological and anthropogenic factors at multiple scales when selecting breeding sites. These multiscale models can be used to identify and prioritize the conservation of preferred nesting habitat for Common Loon populations. RESUME. Le Plongeon huard (Gavia immer) est considere comme un representant emblematique et ecologiquement important de la faune dependante du milieu aquatique en Amerique du Nord. L’aire de reproduction du Plongeon huard a subi une contraction depuis le siecle passe en raison de la degradation de son habitat consecutive au derangement humain et a l’augmentation de l’occupation humaine sur les bords de lacs. Nous avons choisi le cas du New Hampshire, E.-U., car il y existe un programme de suivi a long terme effectue par le Loon Preservation Committee, qui collige les donnees biologiques sur l’espece depuis 1976. La population du Plongeon huard est repartie partout dans cet Etat, selon une grande variete de milieux lacustres, de conditions de qualite d’eau et de degres de derangement humain. Nous avons utilise une approche multi-echelles afin d’evaluer la relation entre le Plongeon huard et son habitat de nidification, dans trois ecoregions physiographiques naturelles au New Hampshire. Ces differentes echelles refletent d’autres caracteristiques relatives au Plongeon huard, comme les territoires, les domaines vitaux et les influences lac-paysage. Nous avons elabore des modeles multi-echelles ecoregionaux et les avons compares a des modeles tenant compte d’une seule echelle pour evaluer leur performance a distinguer correctement l’habitat de nidification du Plongeon huard. D’apres les criteres de la theorie de l’information, les observations empiriques soutiennent les modeles multi-echelles tout comme les modeles a une seule echelle, dans les trois ecoregions, resultat qui justifie une approche fondee sur la moyenne des modeles. Nos resultats U.S. Environmental Protection Agency, Atlantic Ecology Division, SRA International Inc., The Loon Preservation Committee, BioDiversity Research Institute, University of Rhode Island Department of Natural Resources Coastal Institute in Kingston Avian Conservation and Ecology 6(1): 4 http://www.ace-eco.org/vol6/iss1/art4/ laissent croire qu’au moment de selectionner son site de nidification, le Plongeon huard reagit tout autant aux facteurs ecologiques qu’aux facteurs anthropiques, a differentes echelles. Il est possible d’utiliser ces modeles multi-echelles pour determiner l’habitat de nidification de predilection des populations de Plongeon huard et pour en prioriser la conservation.