Vignette 15: Eelgrass Variations Ties to Sea Level Variations

This vignette shares an overview of the process and results of a long-term eelgrass monitoring effort at the mouth of Sequim Bay. Coupling these local long-term findings with research and monitoring across the Salish Sea and the globe will help better understand the longer-term effects of global warming and perhaps other human and natural-derived pressures on coastal ecosystems, and provide clues on how to make these systems more resilient to pressures

Eelgrass (Zostera marina) biomass models for predicting restoration potential in Puget Sound

We developed a biomass model to support the Puget Sound Partnership’s goal of increasing the area of eelgrass (Zostera marina) in Puget Sound by 20% by 2020. The model has helped with the identification of potential restoration sites by predicting eelgrass growth based upon inputs of light, temperature, salinity and water depth. We built upon a tropical seagrass model first adapted to Z. marina by the US EPA Western Ecology Division. We made further adaptations for Puget Sound, using data on the effects of light, temperature, and salinity on photosynthesis and respiration collected in Sequim Bay and our laboratory. To predict the potential for eelgrass growth, we ran the model using water elevation, temperature, and salinity output from a 3D hydrodynamic model of Puget Sound. Data on turbidity are scarce; we used marine water quality monitoring data to characterize light attenuation for regions with particular water quality characteristics. We found that model predictions were improved by using functions and parameters developed from the local eelgrass population. The model reasonably predicted a ten-week time series of biomass data collected in Sequim Bay. When used as an index of habitat suitability, the model predicted eelgrass cover fairly well in some areas of Puget Sound (e.g. river deltas, Northern Puget Sound) and less well in others (South Sound, highly developed areas of Central Puget Sound). Model results were used to locate sites for test plantings towards identifying restoration sites. Future applications include estimating restoration potential within smaller regions using local monitoring data. The model would benefit from additional data, including physiological data over a broader range of environmental conditions, subpopulations, and seasons. In addition, improved information on light attenuation is necessary for spatially and temporally comprehensive predictions in areas as complex and variable as Puget Sound

Restoration action effectiveness: employing the concept of net ecosystem improvement

The mission statement of the Northwest Straits Initiative includes ‘improving ecosystem health’ of the Strait of Juan de Fuca and Northern Puget Sound by restoring and protecting natural habitats and resources. For the Initiative, and many other programs, defining ‘ecosystem health’ and developing relevant and measureable health metrics is problematic, and yet critical to both assessing program action effectiveness as well as justifying investments. The Initiative is exploring utilizing the concept of net ecosystem improvement (NEI) to summarize results of actions and couch the results in a broader ecosystem perspective. Net improvement is defined as following development; there is an increase in the size and natural functions of an ecosystem or natural components of the ecosystem (Thom et al. 2005. Restoration Ecol. v. 13). Conceptual models are used to summarize knowledge and guide actions to improve the ecosystem. NEI is calculated by estimating the change in function times the change in area over which this change in function occurred including both temporal and spatial aspects. For example, the anchor out zone project managed by the Jefferson County Marine Resources Committee in Port Townsend protects 21.6ha (52 acres) of eelgrass. Without this protection most if not all of the eelgrass would be lost. Using data from other areas, we estimated that 3,998 - 66,077 Dungeness crab (primarily juveniles) and net production by eelgrass of 2,083 metric tons wet wt y-1, are protected. Based on WDNR monitoring (Christiaen et al. 2017), this area of eelgrass protected amounts to 0.5 – 0.8% of the total eelgrass area in the Straits, and 0.5% of the Puget Sound Partnership 2020 eelgrass recovery goal of ~4000ha. Estimating NEI and placing the results in a broader ecosystem perspective is possible for many actions taken by the Initiative’s Marine Resource Committees, and may be appropriate for other programs

Is local adaptation a factor in planning eelgrass restoration? Initial assessment of responses to temperature by eelgrass growing across a stressor gradient

Large-scale eelgrass restoration in an environment as complex as the Salish Sea requires estimating the effects of a wide range of environmental conditions (e.g. temperature, salinity, turbidity) on the effectiveness of restoration actions in different locations. We have developed a spatial model of eelgrass growth in response to environmental drivers, based on physiological data collected in Sequim Bay, WA, to aid in identifying restoration sites. However, field tests suggest that the model underestimates the capability of eelgrass to grow in conditions more stressful than Sequim Bay. A critical uncertainty is the extent of localized genotypic and/or phenotypic adaptations by eelgrass to high temperature and light limitation, which would affect our ability to predict restoration success over large scales with a single model. We have conducted an initial set of experiments to explore the physiological response of eelgrass collected from multiple locations across a temperature stress gradient. We collected eelgrass samples from two high-stress locations (South Sound and Hood Canal), and one low-stress location (Sequim Bay) and measured photosynthesis and respiration rates of cleaned, healthy leaf sections via instantaneous oxygen flux in light and dark bottles across a range of temperatures. The samples had notable differences in morphology and epiphytes. We found that respiration and photosynthesis did not differ between sites across the temperature treatments. Counter to expectations, eelgrass from more stressful locations had higher respiration rates, though the difference was not statistically significant. We observed significantly higher gross and net productivity at 25° C for eelgrass from Hood Canal. The results suggest that eelgrass populations throughout Puget Sound may not be as differentially adapted to temperature as we expected, despite discrepancies between modeling and field observations. We hope to extend this study with additional data collection, including moderate- to long-term common garden growth experiments for multiple stressors

Structural imaging biomarkers of sudden unexpected death in epilepsy.

Sudden unexpected death in epilepsy is a major cause of premature death in people with epilepsy. We aimed to assess whether structural changes potentially attributable to sudden death pathogenesis were present on magnetic resonance imaging in people who subsequently died of sudden unexpected death in epilepsy. In a retrospective, voxel-based analysis of T1 volume scans, we compared grey matter volumes in 12 cases of sudden unexpected death in epilepsy (two definite, 10 probable; eight males), acquired 2 years [median, interquartile range (IQR) 2.8] before death [median (IQR) age at scanning 33.5 (22) years], with 34 people at high risk [age 30.5 (12); 19 males], 19 at low risk [age 30 (7.5); 12 males] of sudden death, and 15 healthy controls [age 37 (16); seven males]. At-risk subjects were defined based on risk factors of sudden unexpected death in epilepsy identified in a recent combined risk factor analysis. We identified increased grey matter volume in the right anterior hippocampus/amygdala and parahippocampus in sudden death cases and people at high risk, when compared to those at low risk and controls. Compared to controls, posterior thalamic grey matter volume, an area mediating oxygen regulation, was reduced in cases of sudden unexpected death in epilepsy and subjects at high risk. The extent of reduction correlated with disease duration in all subjects with epilepsy. Increased amygdalo-hippocampal grey matter volume with right-sided changes is consistent with histo-pathological findings reported in sudden infant death syndrome. We speculate that the right-sided predominance reflects asymmetric central influences on autonomic outflow, contributing to cardiac arrhythmia. Pulvinar damage may impair hypoxia regulation. The imaging findings in sudden unexpected death in epilepsy and people at high risk may be useful as a biomarker for risk-stratification in future studies

Eelgrass (Zostera marina) restoration in Puget Sound: restoration tools, successes and challenges

Eelgrass (Zostera marina) is one of 25 Vital Signs to track the health of Puget Sound and restoration of this critical nearshore habitat is part of the overall regional recovery strategy. Eelgrass restoration will provide a multitude of benefits, ranging from habitat for species to ameliorating the effects of climate change. Since 2013, the Washington State Department of Natural Resources has led regional evaluation of potential eelgrass restoration sites and transplanting in Washington State. Through collaborations we have developed and tested strategies to enhance transplant success and restore natural processes. We developed an eelgrass transplant suitability model to identify potential restoration sites using key variables essential for seagrass production and long-term resilience in a changing environment. Eelgrass was planted at five sites for initial model verification with an additional 81 test sites planted between 2013 and 2017 to identify areas suitable for large scale restoration. Eelgrass test transplant results varied and 15 sites with the highest success were selected for large-scale transplantation. A comparison of standard transplant methods was performed and preliminary results suggest that proper method selection plays an important role in transplant success. Long-term monitoring is scheduled with an emphasis on the success of specific donor stocks, the recovery of donor sites, and the effect seagrass restoration has on water chemistry. The restoration process has endured challenges that ranged from permitting issues to anthropogenic and environmental stressors. However, issue specific solutions and adaptive management allowed the restoration process to progress and contribute valuable information towards strategies to recover this valuable habitat in the region

Altered Amygdala Volumes and Microstructure in Focal Epilepsy Patients With Tonic-Clonic Seizures, Ictal, and Post-convulsive Central Apnea

Objectives Sudden unexpected death in epilepsy (SUDEP) is a leading cause of death for patients with epilepsy; however, the pathophysiology remains unclear. Focal‐to‐bilateral tonic–clonic seizures (FBTCS) are a major risk factor, and centrally‐mediated respiratory depression may increase the risk further. Here, we determined the volume and microstructure of the amygdala, a key structure that can trigger apnea in people with focal epilepsy, stratified by the presence or absence of FBTCS, ictal central apnea (ICA), and post‐convulsive central apnea (PCCA). Methods Seventy‐three patients with focal impaired awareness seizures without FBTC seizures (FBTCneg group) and 30 with FBTCS (FBTCpos group) recorded during video electroencephalography (VEEG) with respiratory monitoring were recruited prospectively during presurgical investigations. We acquired high‐resolution T1‐weighted anatomic and multi‐shell diffusion images, and computed neurite orientation dispersion and density imaging (NODDI) metrics in all patients with epilepsy and 69 healthy controls. Amygdala volumetric and microstructure alterations were compared between three groups: healthy subjects, FBTCneg and FBTCpos groups. The FBTCpos group was further subdivided by the presence of ICA and PCCA, verified by VEEG. Results Bilateral amygdala volumes were significantly increased in the FBTCpos cohort compared to healthy controls and the FBTCneg group. Patients with recorded PCCA had the highest increase in bilateral amygdala volume of the FBTCpos cohort. Amygdala neurite density index (NDI) values were decreased significantly in both the FBTCneg and FBTCpos groups relative to healthy controls, with values in the FBTCpos group being the lowest of the two. The presence of PCCA was associated with significantly lower NDI values vs the non‐apnea FBTCpos group (p = 0.004). Significance Individuals with FBTCpos and PCCA show significantly increased amygdala volumes and disrupted architecture bilaterally, with greater changes on the left side. The structural alterations reflected by NODDI and volume differences may be associated with inappropriate cardiorespiratory patterns mediated by the amygdala, particularly after FBTCS. Determination of amygdala volumetric and architectural changes may assist identification of individuals at risk

Evaluating Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2009

This is the sixth annual report of a seven-year project (2004 through 2010) to evaluate the cumulative effects of habitat restoration actions in the lower Columbia River and estuary (LCRE). The project, called the Cumulative Effects Study, is being conducted for the U.S. Army Corps of Engineers Portland District (USACE) by the Marine Sciences Laboratory of the Pacific Northwest National Laboratory (PNNL), the Pt. Adams Biological Field Station of the National Marine Fisheries Service (NMFS), the Columbia River Estuary Study Taskforce (CREST), and the University of Washington. The goal of the Cumulative Effects Study is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the 235-km-long LCRE. Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. From 2005 through 2009, annual field research involved intensive, comparative studies paired by habitat type (tidal swamp versus marsh), trajectory (restoration versus reference site), and restoration action (tidegate replacement vs. culvert replacement vs. dike breach)

Targeting LIF-mediated paracrine interaction for pancreatic cancer therapy and monitoring.

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis largely owing to inefficient diagnosis and tenacious drug resistance. Activation of pancreatic stellate cells (PSCs) and consequent development of dense stroma are prominent features accounting for this aggressive biology1,2. The reciprocal interplay between PSCs and pancreatic cancer cells (PCCs) not only enhances tumour progression and metastasis but also sustains their own activation, facilitating a vicious cycle to exacerbate tumorigenesis and drug resistance3-7. Furthermore, PSC activation occurs very early during PDAC tumorigenesis8-10, and activated PSCs comprise a substantial fraction of the tumour mass, providing a rich source of readily detectable factors. Therefore, we hypothesized that the communication between PSCs and PCCs could be an exploitable target to develop effective strategies for PDAC therapy and diagnosis. Here, starting with a systematic proteomic investigation of secreted disease mediators and underlying molecular mechanisms, we reveal that leukaemia inhibitory factor (LIF) is a key paracrine factor from activated PSCs acting on cancer cells. Both pharmacologic LIF blockade and genetic Lifr deletion markedly slow tumour progression and augment the efficacy of chemotherapy to prolong survival of PDAC mouse models, mainly by modulating cancer cell differentiation and epithelial-mesenchymal transition status. Moreover, in both mouse models and human PDAC, aberrant production of LIF in the pancreas is restricted to pathological conditions and correlates with PDAC pathogenesis, and changes in the levels of circulating LIF correlate well with tumour response to therapy. Collectively, these findings reveal a function of LIF in PDAC tumorigenesis, and suggest its translational potential as an attractive therapeutic target and circulating marker. Our studies underscore how a better understanding of cell-cell communication within the tumour microenvironment can suggest novel strategies for cancer therapy