Natural climate solutions provide robust carbon mitigation capacity under future climate change scenarios

Natural climate solutions (NCS) are recognized as an important tool for governments to reduce greenhouse gas emissions and remove atmospheric carbon dioxide. Using California as a globally relevant reference, we evaluate the magnitude of biological climate mitigation potential from NCS starting in 2020 under four climate change scenarios. By mid-century NCS implementation leads to a large increase in net carbon stored, flipping the state from a net source to a net sink in two scenarios. Forest and conservation land management strategies make up 85% of all NCS emissions reductions by 2050, with agricultural strategies accounting for the remaining 15%. The most severe climate change impacts on ecosystem carbon materialize in the latter half of the century with three scenarios resulting in California ecosystems becoming a net source of carbon emissions under a baseline trajectory. However, NCS provide a strong attenuating effect, reducing land carbon emissions 41-54% by 2100 with total costs of deployment of 752-777 million USD annually through 2050. Rapid implementation of a portfolio of NCS interventions provides long-term investment in protecting ecosystem carbon in the face of climate change driven disturbances. This open-source, spatially-explicit framework can help evaluate risks to NCS carbon storage stability, implementation costs, and overall mitigation potential for NCS at jurisdictional scales.

Btbd11 supports cell-type-specific synaptic function

Synapses in the brain exhibit cell-type-specific differences in basal synaptic transmission and plasticity. Here, we evaluated cell-type-specific specializations in the composition of glutamatergic synapses, identifying Btbd11 as an inhibitory interneuron-specific, synapse-enriched protein. Btbd11 is highly conserved across species and binds to core postsynaptic proteins, including Psd-95. Intriguingly, we show that Btbd11 can undergo liquid-liquid phase separation when expressed with Psd-95, supporting the idea that the glutamatergic postsynaptic density in synapses in inhibitory interneurons exists in a phase-separated state. Knockout of Btbd11 decreased glutamatergic signaling onto parvalbumin-positive interneurons. Further, both in vitro and in vivo, Btbd11 knockout disrupts network activity. At the behavioral level, Btbd11 knockout from interneurons alters exploratory behavior, measures of anxiety, and sensitizes mice to pharmacologically induced hyperactivity following NMDA receptor antagonist challenge. Our findings identify a cell-type-specific mechanism that supports glutamatergic synapse function in inhibitory interneurons-with implications for circuit function and animal behavior.

FMRI study of implicit emotional face processing in patients with MDD with melancholic subtype

Introduction

The accurate perception of facial expressions plays a vital role in daily life, allowing us to select appropriate responses in social situations. Understanding the neuronal basis of altered emotional face processing in patients with major depressive disorder (MDD) may lead to the appropriate choice of individual interventions to help patients maintain social functioning during depressive episodes. Inconsistencies in neuroimaging studies of emotional face processing are caused by heterogeneity in neurovegetative symptoms of depressive subtypes. The aim of this study was to investigate brain activation differences during implicit perception of faces with negative and positive emotions between healthy participants and patients with melancholic subtype of MDD. The neurobiological correlates of sex differences of MDD patients were also examined.

Methods

Thirty patients diagnosed with MDD and 21 healthy volunteers were studied using fMRI while performing an emotional face perception task.

Results

Comparing general face activation irrespective of emotional content, the intensity of BOLD signal was significantly decreased in the left thalamus, right supramarginal gyrus, right and left superior frontal gyrus, right middle frontal gyrus, and left fusiform gyrus in patients with melancholic depression compared to healthy participants. We observed only limited mood-congruence in response to faces of differing emotional valence. Brain activation in the middle temporal gyrus was significantly increased in response to fearful faces in comparison to happy faces in MDD patients. Elevated activation was observed in the right cingulate for happy and fearful faces, in precuneus for happy faces, and left posterior cingulate cortex for all faces in depressed women compared to men. The Inventory for Depressive Symptomatology (IDS) score was inversely correlated with activation in the left subgenual gyrus/left rectal gyrus for sad, neutral, and fearful faces in women in the MDD group. Patients with melancholic features performed similarly to controls during implicit emotional processing but showed reduced activation.

Discussion and conclusion

This finding suggests that melancholic patients compensate for reduced brain activation when interpreting emotional content in order to perform similarly to controls. Overall, frontal hypoactivation in response to implicit emotional stimuli appeared to be the most robust feature of melancholic depression.

Blimp-1/PRDM1 and Hr3/RORβ specify the blue-sensitive photoreceptor subtype in Drosophila by repressing the hippo pathway

During terminal differentiation of the mammalian retina, transcription factors control binary cell fate decisions that generate functionally distinct subtypes of photoreceptor neurons. For instance, Otx2 and RORβ activate the expression of the transcriptional repressor Blimp-1/PRDM1 that represses bipolar interneuron fate and promotes rod photoreceptor fate. Moreover, Otx2 and Crx promote expression of the nuclear receptor Nrl that promotes rod photoreceptor fate and represses cone photoreceptor fate. Mutations in these four transcription factors cause severe eye diseases such as retinitis pigmentosa. Here, we show that a post-mitotic binary fate decision in Drosophila color photoreceptor subtype specification requires ecdysone signaling and involves orthologs of these transcription factors: Drosophila Blimp-1/PRDM1 and Hr3/RORβ promote blue-sensitive (Rh5) photoreceptor fate and repress green-sensitive (Rh6) photoreceptor fate through the transcriptional repression of warts/LATS, the nexus of the phylogenetically conserved Hippo tumor suppressor pathway. Moreover, we identify a novel interaction between Blimp-1 and warts, whereby Blimp-1 represses a warts intronic enhancer in blue-sensitive photoreceptors and thereby gives rise to specific expression of warts in green-sensitive photoreceptors. Together, these results reveal that conserved transcriptional regulators play key roles in terminal cell fate decisions in both the Drosophila and the mammalian retina, and the mechanistic insights further deepen our understanding of how Hippo pathway signaling is repurposed to control photoreceptor fates for Drosophila color vision.

VeVaPy, a Python Platform for Efficient Verification and Validation of Systems Biology Models with Demonstrations Using Hypothalamic-Pituitary-Adrenal Axis Models

In order for mathematical models to make credible contributions, it is essential for them to be verified and validated. Currently, verification and validation (V&V) of these models does not meet the expectations of the system biology and systems pharmacology communities. Partially as a result of this shortfall, systemic V&V of existing models currently requires a lot of time and effort. In order to facilitate systemic V&V of chosen hypothalamic-pituitary-adrenal (HPA) axis models, we have developed a computational framework named VeVaPy-taking care to follow the recommended best practices regarding the development of mathematical models. VeVaPy includes four functional modules coded in Python, and the source code is publicly available. We demonstrate that VeVaPy can help us efficiently verify and validate the five HPA axis models we have chosen. Supplied with new and independent data, VeVaPy outputs objective V&V benchmarks for each model. We believe that VeVaPy will help future researchers with basic modeling and programming experience to efficiently verify and validate mathematical models from the fields of systems biology and systems pharmacology.

OR16-1 How Strong and Sustained Activation of the Estrogen Receptor-mediated Anticipatory Unfolded Protein Response Kills Breast and Ovarian Cancer Cells

In orthotopic xenografts and a PDX, our anticancer drug ErSO eradicates primary and metastatic therapy-resistant estrogen receptor alpha (ERα) positive breast cancer, and induces near-complete regression of ovarian cancer. The mechanism by which ErSO induces necrosis and kills ER positive cancer cells was unknown. From genome-wide CRISPR-Cas9 screens in MCF-7 and T47D cells with negative selection against first-generation BHPI and second-generation ErSO, and follow-on experiments, we identified the Ca2+ activated, plasma membrane Na+ channel TRPM4 as the executioner protein that BHPI and ErSO use to induce necrosis. Notably, in 6 ERα+ breast and ovarian cancer cell lines, knockout of TRPM4 completely abolished the ability of ErSO to induce death of cancer cells. Moreover, TRPM4 mRNA and protein were dramatically down-regulated in breast cancer cells selected for resistance to BHPI and ErSO. Furthermore, in a mouse xenograft, while ErSO induced near complete regression of orthotopic MCF-7-ERY537S-luciferase tumors, ErSO had no effect on the TRPM4 knockout tumors, which continued their robust growth. Since necrosis, but not most other death pathways, activates immune cells, inducing immunogenic cell death, this provides a new avenue for enhancing cancer immunotherapy. Importantly, medium from ErSO-treated wild type MCF-7 cells, but not medium from TRPM4 knockout cells, robustly activates human THP-1 monocytes and greatly increases their migration. BHPI and ErSO-induced initial anticipatory unfolded protein response (a-UPR) activation results in elevated cytosolic Ca2+, opening the plasma membrane TRPM4 channel, eliciting a rapid influx of external Na+, accompanying Cl- to balance the charge, and water to maintain osmolality. This swells the cells, causing osmotic stress. Importantly, it is the osmotic stress that sustains UPR hyperactivation, leading to ATP depletion, which contributes to membrane rupture and rapid necrotic cell death and to near complete inhibition of protein synthesis that ultimately kills any surviving cancer cells . Suggesting a broad role of TRPM4 in the actions of necrosis inducing anticancer drugs, TRPM4 knockout also inhibited necrosis induced by unrelated anticancer therapies, the mitochondrial targeting oncolytic peptide, LTX-315 and the Ca2+ channel targeting agent, Englerin A. Since increasing expression TRPM4 by viral transduction results in progressively increased sensitivity of ER positive breast cancer cells to killing by ErSO, this enables identification of breast cancer patients whose elevated TRPM4 levels make them most likely to benefit from this novel therapy. The TRPM4 pathway is a new mechanism for sustained lethal activation of the UPR and for targeting ER positive breast and ovarian cancer.

Presentation: Sunday, June 12, 2022 11:00 a.m. - 11:15 p.m.

Long drives and red tape: mapping rural veteran access to primary care using causal-loop diagramming

Background

Rural veterans experience more challenges than their urban peers in accessing primary care services, which can negatively impact their health and wellbeing. The factors driving this disparity are complex and involve patient, clinic, health system, community and policy influences. Federal policies over the last decade have relaxed requirements for some veterans to receive primary care services from community providers through their VA benefits, known as community care.

Methods

We used a participatory systems mapping approach involving causal-loop diagramming to identify interrelationships between variables underlying challenges to veteran access to primary care and potential opportunities for change—known as leverage points in systems science. Our methods involved a secondary analysis of semi-structured qualitative interviews with rural veterans, VA staff, non-VA clinic staff and providers who serve rural veterans, and veteran service officers (VSOs) in the Northwest region of the US, followed by a two-part participatory modeling session with a study advisory board. We then applied Meadows’s leverage point framework to identify and categorize potential interventions to improve rural veteran access to primary care.

Results

The final model illustrated challenges at the veteran, clinic, and system levels as experienced by stakeholders. Main components of the diagram pertained to the choice of VA or non-VA primary care, veteran satisfaction with the VA, enrollment in VA benefits and other insurance, community care authorization, reimbursement of non-VA care, referrals to specialty care, record sharing and communication between VA and non-VA providers, institutional stability of the VA, and staffing challenges. Fourteen interventions, including administrative and communications changes, were identified by analyzing the model using the leverage points framework.

Conclusions

Our findings illustrate how challenges rural veterans face accessing health care are interconnected and persist despite recent changes to federal law pertaining to the VA health care system in recent years. Systems mapping and modeling approaches such as causal-loop diagramming have potential for engaging stakeholders and supporting intervention and implementation planning.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-08318-2.

Assessing trace-elements as indicators of marine finfish aquaculture across three distinct Canadian coastal regions

Several trace-elements have been identified as indicators of finfish aquaculture organic enrichment. In this study, sediment sampling at finfish farms was completed as part of an Aquaculture Monitoring Program in three distinct Canadian regions. Despite diverse datasets, multivariate analyses show a consistent clustering of known direct (Cu and Zn) and indirect (Cd, Mo and U) tracers of aquaculture activities with sediment organic matter (OM) and/or total dissolved sulfides concentrations. OM content was also a predictor of Cu, Zn, Mo and U concentrations according to decision tree analyses. Distance from cages did not emerge as a strong driver of differences among sampling points; however, a tendency towards negative associations is clear especially for Zn. Enriched stations as determined after geochemical normalization were mostly localized within 150 m of net-pens. Selected trace-elements (in particular Zn) can be useful indicators of aquaculture organic enrichment in different ecosystems and valuable tools for monitoring programs.

Liver x receptor alpha drives chemoresistance in response to side-chain hydroxycholesterols in triple negative breast cancer

Triple negative breast cancer (TNBC) is challenging to treat successfully because targeted therapies do not exist. Instead, systemic therapy is typically restricted to cytotoxic chemotherapy, which fails more often in patients with elevated circulating cholesterol. Liver x receptors are ligand-dependent transcription factors that are homeostatic regulators of cholesterol, and are linked to regulation of broad-affinity xenobiotic transporter activity in non-tumor tissues. We show that LXR ligands confer chemotherapy resistance in TNBC cell lines and xenografts, and that LXRalpha is necessary and sufficient to mediate this resistance. Furthermore, in TNBC patients who had cancer recurrences, LXRalpha and ligands were independent markers of poor prognosis and correlated with P-glycoprotein expression. However, in patients who survived their disease, LXRalpha signaling and P-glycoprotein were decoupled. These data reveal a novel chemotherapy resistance mechanism in this poor prognosis subtype of breast cancer. We conclude that systemic chemotherapy failure in some TNBC patients is caused by co-opting the LXRalpha:P-glycoprotein axis, a pathway highly targetable by therapies that are already used for prevention and treatment of other diseases.

L-methylfolate augmentation of selective serotonin reuptake inhibitors (SSRIS) for major depressive disorder: Results of two randomized, double-blind trials

Introduction

Two randomized, controlled trials of L-methylfolate augmentation of SSRIs for major depressive disorder (MDD) were conducted using a novel study design (sequential parallel comparison design- SPCD).

Objectives/aims

To evaluate the efficacy of L-methylfolate augmentation using the Hamilton Depression Rating Scale.

Methods

In study one (TRD-1), 148 outpatients with SSRI-resistant MDD were enrolled in a 60-day, SPCD study, divided into two 30-day periods (phases 1 and 2). Patients were randomized 2:3:3 to receive L-methylfolate (7.5mg/d in phase 1, 15mg/d in phase 2), placebo in phase 1 followed by L-methylfolate 7.5mg/d in phase 2, or placebo for both phases. Study two (TRD-2) involved 75 patients and was identical in design to TRD-1 except for the dose of L-methylfolate (15mg only).

Results

In the TRD-1 Study, L-methylfolate 7.5 mg/d was not found to be more effective than placebo. In phase 1 of the TRD-2 Study, 37% of patients on L-methylfolate 15mg/d responded and 18% of placebo patients responded, while in phase 2 among placebo non-responders, the response rates were 28% on L-methylfolate 15mg/d and 9.5% on placebo. When phases 1 and 2 were pooled according to the SPCD model, the difference in response rates was statistically significant in favor of L-methylfolate (p = 0.0399). The rates of spontaneously reported AEs and rates of study discontinuation appear r comparable between L-methylfolate and placebo in both studies. Rates of study discontinuation were also comparable

Conclusions

These studies suggest that L-methylfolate 15 mg/d may be a safe and effective augmentation strategy for inadequate response to SSRIs.

Genome sequence and description of Blautia brookingsii SG772 sp. nov., a novel bacterial species isolated from human faeces

An anaerobic isolate SG772 belonging to the genus Blautia was isolated from a healthy human faecal sample. When compared using 16s rRNA sequence identity, SG772 showed only 94.46% similarity with its neighbour species Blautia stercoris. As strain SG772 showed both phenotypic and genomic differences from other members of the type species within the genus Blautia, we propose the designation of SG772 as novel species 'Blautia brookingsii SG772^T'.

Autologous Adipose Tissue-Derived Mesenchymal Stem Cells Introduced by Biliary Stents or Local Immersion in Porcine Bile Duct Anastomoses

Biliary complications (strictures and leaks) represent major limitations in living donor liver transplantation. Mesenchymal stem cells (MSCs) are a promising modality to prevent biliary complications because of immunosuppressive and angiogenic properties. Our goal was to evaluate the safety of adipose-derived MSC delivery to biliary anastomoses in a porcine model. Secondary objectives were defining the optimal method of delivery (intraluminal versus extraluminal) and to investigate MSC engraftment, angiogenesis, and fibrosis. Pigs were divided into 3 groups. Animals underwent adipose collection, MSC isolation, and expansion. Two weeks later, animals underwent bile duct transection, reanastomosis, and stent insertion. Group 1 received plastic stents wrapped in unseeded Vicryl mesh. Group 2 received stents wrapped in MSC-seeded mesh. Group 3 received unwrapped stents with the anastomosis immersed in an MSC suspension. Animals were killed 1 month after stent insertion when cholangiograms and biliary tissue were obtained. Serum was collected for liver biochemistries. Tissue was used for hematoxylin-eosin and trichrome staining and immunohistochemistry for MSC markers (CD44 and CD34) and for a marker of neoangiogenesis (CD31). There were no intraoperative complications. One pig died on postoperative day 3 due to acute cholangitis. All others recovered without complications. Cholangiography demonstrated no biliary leaks and minimal luminal narrowing. Surviving animals exhibited no symptoms, abnormal liver biochemistries, or clinically significant biliary stricturing. Group 3 showed significantly greater CD44 and CD34 staining, indicating MSC engraftment. Fibrosis was reduced at the anastomotic site in group 3 based on trichrome stain. CD31 staining of group 3 was more pronounced, supporting enhanced neoangiogenesis. In conclusion, adipose-derived MSCs were safely applied to biliary anastomoses. MSCs were locally engrafted within the bile duct and may have beneficial effects in terms of fibrosis and angiogenesis.

Health Education Training Embedded in a Microfinance Platform Associated with Safer Sexual Behavior in Haitian Women

Sexual health education interventions have generally yielded modest impact, but may be more successful when integrated into programs designed to alleviate poverty and empower women. Between December 2017 and February 2018, we interviewed 304 Haitian female microfinance clients, 75 of whom had received health education training delivered within their regular meetings. Participants reported six key sexual health outcomes. We used log-binomial models to estimate the association between health education training and each outcome, and tested for interaction by age and literacy status. Women with health education training reported more condom use with unfaithful partners [PR (95% CI) 1.78 (1.04, 3.02)], more HIV testing [PR (95% CI) 1.56 (1.28, 1.90)], and fewer STI symptoms [PR (95% CI) 0.37 (0.19, 0.73)], compared to women with no training. Some of the associations were stronger among older women [e.g. HIV testing: PR (95% CI) 2.09 (1.49, 2.82)] and illiterate women [e.g. condom use: PR (95% CI) 3.46 (1.05, 11.38)]. These findings add to the growing body of evidence demonstrating the potential to use microfinance programs as platforms for health education delivery, and provide the first evidence for the association in Haiti.

Individual- and county-level determinants of high breast cancer incidence rates

Background

Age-adjusted breast cancer rates vary across and within states. However, most statistical models inherently identify either individual- or area-level determinants to explain geographic disparities in breast cancer rates and ignore the effects of the other level of determinants. We present a micro-macro modelling approach that incorporates both levels of determinants to better explain this variability and to discover opportunities to reduce breast cancer rates.

Methods

Individual-level data about breast cancer risk factors from eligible Arkansas Rural Community Health (ARCH) study participants (n=13,554) was supplemented with publicly available county-level data using a novel micro-macro statistical approach. This model uses individual-level data to account for aggregation-induced biases, to predict county-level breast cancer incidence rates across Arkansas.

Results

County-level breast cancer incidence rates ranged from 80.9 to 161.6 per 100,000 population. The best-fit model, which included individual-level predicted risk based on the Gail/CARE models, county-level population density (log transformed), and lead exposure (log transformed), explained 14.1% of the county variance.

Conclusions

Our results support theoretical models that maintain that area-level determinants of breast cancer incidence are key risk factors in addition to established individual risks.

SAT-332 ERRα Modulates Genes of Importance to Macrophage Biology and Breast Cancer Progression

Breast cancer is a leading cause of death among women in the US with mortality most often due to metastasis. Bone is a common primary site of metastasis, and it is known that local bone quality dictates the susceptibility of this tissue to colonization. Estrogen-related receptor alpha (ERRα) is a nuclear receptor expressed in a variety of tissues and is involved in development, metabolic regulation, bone physiology, and immune cell differentiation. ERRα is expressed in macrophages, and there is a growing body of literature suggesting that macrophages are involved in both bone physiology as well as metastatic progression. Therefore, we hypothesized that the activity of this receptor within macrophages would have important patho-physiological consequences. Using RAW264.7 cells as a model, we first explored the expression of genes key to macrophage function. RAW264.7 cells polarized into the ‘M1’ state with lipopolysaccharide and IFNγ for 24hrs. Interestingly, when ERRα was overexpressed in these cells, we observed a significant reduction in interleukin 6 (IL-6) and RANKL expression, but an increase in the classic M1 markers, NOS2 and CD82. Conversely, when cells were treated with XCT-790, a small molecule antagonist and degrader of ERRα, IL-6 mRNA was increased, while NOS2 and CD86 were reduced. IL-6 and RANKL are known to be involved in bone resorption, and IL-6 has been implicated in cancer cell migration and the promotion of tumor progression. Furthermore, the production of nitric oxide by NOS2 can impair T cell expansion thus facilitating immune-escape by cancer cells. Thus, we speculated that macrophage activation of ERRα may promote breast cancer metastasis to the bone. We first confirmed that the bone-tropic MDA-MB-231 breast cancer cells migrate towards macrophages. We found that this migration was attenuated when IL-6 was depleted. Cholesterol has recently been identified as an agonist for ERRα. Therefore, we placed mice on a normal or high cholesterol diet and grafted with MDA-MB-231 cells. Contrary to our data indicating that ERRα activation would be protective, mice on a high cholesterol diet developed significantly more bone lesions. Hence, the effects of cholesterol on promoting breast cancer metastasis to the bone could not be explained solely by its ERRα activity. In conclusion, we have found that ERRα functions to attenuate cytokine release and decrease NOS2 expression in M1 polarized macrophages. Although cholesterol has been described as an ERRα agonist, a high cholesterol diet increased metastasis to the bone, contrary to what would be expected based on the ERRα inhibition of IL-6 and NOS2. Our data suggest that further studies are required to better elucidate the role of ERRα, prior to developing this nuclear receptor as a therapeutic target.

SAT-340 27-Hydroxycholesterol Acts on Myeloid Cells to Inhibit T Cell Expansion

Breast cancer is the most commonly diagnosed cancer and among the leading causes of death among women in the United States. Our previous work has found that a metabolite of cholesterol, 27-hydroxycholesterol (27HC) promotes breast cancer metastasis in preclinical models. 27HC is a ligand of both the estrogen receptor (ER) and liver X receptor (LXR). Intriguingly, the pro-metastatic effects of 27HC require the presence of myeloid-immune cells. This cell type has been implicated in suppressing acquired immunity, allowing cancer cells to escape immune surveillance. Therefore, we hypothesized that 27HC suppresses the immune system to promote metastasis. To elucidate the immunomodulatory capacity of 27HC, we co-cultured vehicle- or 27HC-treated bone marrow-derived macrophages (BMDMs) with T cells. In support of our hypothesis, we found that 27HC-treated BMDMs inhibited T cell expansion in a dose-dependent manner. Additionally, co-cultured BMDMs treated with 27HC resulted in decreased granzyme B in CD8+ cytotoxic T cells, potentially reducing their capacity to kill cancer cells. The immunosuppressive effect of 27HC-treated BMDMs persisted even without a direct contact between BMDMs and T cells, suggesting that the T cell inhibition is unlikely due to 27HC’s modulation of macrophages’ cell surface markers, in particular MHCII and CD80/86, which are commonly used for BMDM-T cell communication. In order to determine the mechanisms by which 27HC-treated BMDMs suppress T cell proliferation, we first evaluated the relative contributions of two receptors known to bind 27HC: the ERs and LXRs. To this end, BMDMs were exposed to pharmacologic antagonists of, or siRNA against the ERs or LXRs. These BMDMs were subsequently co-cultured with activated T cells to study their impact on T cell proliferation. Interestingly, 27HC’s immunosuppressive capacity required LXR in BMDMs, but not ER, as both siRNA knockdown and pharmacological inhibition of LXR significantly rescued the BMDM-inhibited T cell expansion. A subsequent cytokine array indicated that 27HC treatment could induce the secretion of anti-inflammatory cytokines, potential mediators of the observed decrease in T cell expansion. Therefore, our results suggest that 27HC affects the microenvironment of breast cancer by altering the activity of antigen-presenting cells through the modulation of LXR. This in turn reduces the expansion of T cell function, ultimately resulting in immune escape and tumor progression. Our ongoing work is aimed at elucidating the 27HC-induced LXR signaling pathway in BMDMs and further identifying the downstream targets of 27HC involved in mediating this immunosuppressive phenotype. Our work is of considerable importance given the prevalence of hypercholesterolemia as well as metastatic breast cancer. This work was supported by the grants from the NCI and DOD-BCRP to ERN (R00CA172357, BC171214).

Correction: The distributional impact of a green payment policy for organic fruit

[This corrects the article DOI: 10.1371/journal.pone.0211199.].

Self-stigma of antidepressant users through secondary analysis of PhotoVoice data

Introduction:

Aspects of self-stigma and medication-related stigma among individuals with depressive disorders remain largely unexplored. The primary objective of this study is to highlight and characterize self-stigma and medication-related stigma experiences of antidepressant users.

Methods:

This is a secondary analysis of data obtained from PhotoVoice studies examining psychotropic medication experiences. Transcripts of reflections from 12 individuals self-reporting a depressive disorder diagnosis and receipt of a prescription for an antidepressant were included. A directed content analysis approach based on expansion of the Self-Stigma of Depression Scale and an iterative process of identification of medication-stigma and stigma-resistance were used. Total mentions of self-stigma, stigma resistance, medication stigma, and underlying themes were tallied and evaluated.

Results:

Self-stigma was mentioned a total of 100 times with at least 2 mentions per participant. Self-blame was the most prominent construct of self-stigma and was mentioned nearly twice as often as any other self-stigma construct. Most participants also made mentions of self-stigma resistance. Half of the individual participants mentioned stigma resistance more times than they mentioned self-stigma, which suggests some surmounting of self-stigma. Medication-related stigma was also prominent, denoting negativity about the presence of medications in one's life.

Discussion:

Self-stigma related to self-blame may be problematic for antidepressant users. Identification and measurement of stigma resistance, especially in peer interactions, may represent a promising concept in overcoming self-stigma. Future work should explore emphasizing self-blame aspects when designing interventions to reduce self-stigma among individuals with depressive disorders and explore development of tools to measure stigma resistance.

Abstract TP190: Incongruence Between Survivors and Family Caregivers About Survivor Function is Associated With Poor Outcomes for Both Members of the Dyad

Introduction: Stroke survivors (SS) and their family caregivers (CG) often disagree about how well the survivor is regaining function. This disagreement (or “incongruence”) may contribute to poor outcomes. This study explored the extent to which incongruence: (1) Differs by survivor function domain (memory/thinking, communication, IADLs, mobility, social participation); (2) Increases or decreases over time without intervention, and; (3) Is associated with emotional distress, subjective stress, and depressive symptoms in both SS and CG.

Methods: Structured survey interviews based on valid measures were conducted with 31 SS and CG separately, at 3 and 6 months post-stroke (enrollment and follow-up). Paired sample t-tests were used to examine incongruence in each domain, at enrollment and follow-up, as well as changes in incongruence over time. Bivariate correlations were used to examine the association between incongruence at enrollment and SS and CG outcomes at follow-up. A less stringent alpha (p=.10) was used due to the exploratory nature of the study.

Results: SS generally perceived their function as better than CG perceived it at each time point, with significant differences in the memory/thinking (p<.05) and communication (p<.05) domains. Incongruence did not change naturally over time, except for social participation incongruence which showed a marginal increase (p<.10). For SS: IADL incongruence at enrollment was associated with follow-up emotional distress (p<.05) and depressive symptoms (p<.10). For CG: IADL incongruence at enrollment was associated with follow-up emotional distress (p<.10), stress (p<.01), and depressive symptoms (p<.01); communication incongruence was associated with emotional distress (p<.10) and stress (p<.10); and mobility incongruence was associated with depressive symptoms (p<.10).

Conclusions: This study supports previous research showing that SS and CG often have incongruent perceptions about survivor function. Additionally, it demonstrates that incongruence generally does not improve by itself and that it may be detrimental for both SS and CG outcomes. Further research with larger samples should be directed at the mitigation of incongruence and strategies to improve outcomes for both SS and CG.

Serological evidence for the co-circulation of two lineages of influenza D viruses in equine populations of the Midwest United States

Influenza D virus (IDV) is a newly described influenza type of the Orthomyxoviridae virus family that was first isolated from diseased swine in 2011 and has subsequently been detected in cattle around the world in 2014. In addition, serological evidence for IDV infection in humans has been recently established. Despite all the progress, the full range of susceptible hosts for this novel virus has yet to be determined, but includes swine, bovine, small ruminants and human. This study was designed to determine if equine is a possible host to this newly emerging influenza virus. Three hundred and sixty-four equine serum samples were collected in 2015 from 141 farms within the Midwestern United States. Serum samples were examined using hemagglutination inhibition (HI) assay against two established IDV lineages (D/OK and D/660) and one IDV-related human ICV lineage (C/JHB). Results of this study showed 44 (44 of 364, 12%) samples positive for antibodies against D/OK, 39 (39 of 364, 11%) samples positive for antibodies against D/660, and 41 (41 of 364, 11%) samples positive for antibodies against C/JHB. A subset of these samples was further confirmed via microtitre neutralization (MN) assay. Our data demonstrated that horses are susceptible to two lineages of IDV, and that these viruses were present in equine populations throughout multiple Midwestern states of the United States. These findings continue to support the need for further surveillance of IDV viruses in agricultural species to work towards a better understanding of the full host range and natural reservoirs of influenza D virus.

Geographic variability in gestational weight gain: a multilevel population-based study of women having term births in Florida (2005-2012)

PURPOSE

We examined the extent of geographic variability in gestational weight gain (GWG), identified areas where women have suboptimal GWG, and evaluated whether individual- and area-level factors account for such variability.

METHODS

We conducted a population-based cohort study including 1,385,574 women delivering term, singleton, and live births in Florida. We used a Bayesian, structured additive regression with a spatial function to analyze data from Florida's birth certificates (2005-2012) and ZIP code tabulation areas (ZCTAs; 2010 Census).

RESULTS

The prevalence of insufficient (7.7%-42.9%) and excessive (17.1%-82.4%) GWG varied widely within Florida. Geographic variability was not explained by risk factors under study. Clusters in Orlando, Tampa, and Miami exhibited increased likelihood of insufficient GWG, whereas clusters in the Northwest of Florida exhibited increased likelihood of excessive GWG.

CONCLUSIONS

We identified areas in Florida with high likelihood of suboptimal GWG that policy-makers should prioritize in the implementation of programs for optimizing GWG.

Blunted amygdala functional connectivity during a stress task in alcohol dependent individuals: A pilot study

BACKGROUND

Scant research has been conducted on neural mechanisms underlying stress processing in individuals with alcohol dependence (AD). We examined neural substrates of stress in AD individuals compared with controls using an fMRI task previously shown to induce stress, assessing amygdala functional connectivity to medial prefrontal cortex (mPFC).

MATERIALS AND METHODS

For this novel pilot study, 10 abstinent AD individuals and 11 controls completed a modified Trier stress task while undergoing fMRI acquisition. The amygdala was used as a seed region for whole-brain seed-based functional connectivity analysis.

RESULTS

After controlling for family-wise error (p = 0.05), there was significantly decreased left and right amygdala connectivity with frontal (specifically mPFC), temporal, parietal, and cerebellar regions. Subjective stress, but not craving, increased from pre-to post-task.

CONCLUSIONS

This study demonstrated decreased connectivity between the amygdala and regions important for stress and emotional processing in long-term abstinent individuals with AD. These results suggest aberrant stress processing in individuals with AD even after lengthy periods of abstinence.

Abstract P2-10-05: PowerPIINC trial: Changes in tumor proliferation index and quality of life with 7 days of preoperative tamoxifen

BACKGROUND: A decrease in Ki67 has been shown to be a predictor of response to tamoxifen. Previous trials have shown a decreased Ki67 proliferation index in breast tumors with as little as 2 weeks of preoperative tamoxifen. However, shortening the preoperative treatment time in window of opportunity studies increases patient acceptance for trial participation. The POWERPIINC trial examined the effect of 7 days of preoperative tamoxifen on breast tumor proliferation and patient symptoms.

METHODS: Adult women with untreated stage I or II invasive breast cancer that was ER positive (&gt;1%) planning on breast surgery with no contraindications to tamoxifen were enrolled. Women received 20mg of tamoxifen for 7 days up to the day of surgery and for 14 days afterwards. Proliferation was assessed by Ki67 immunohistochemistry before and after 7 days of tamoxifen. The proliferation genes from the PAM50 were also assessed by RT-PCR. Symptoms and QOL were assessed by the FACT-ES, MENQoL, and BMQ.

RESULTS: 52 women were enrolled, and 44 were evaluable for Ki67. The median age was 58.5 years, and the median tumor diameter was 1.2cm. Most women (73%) were post-menopausal. Most tumors were PR positive (88%). Only 8% of tumors were HER2-positive. The Ki67 decreased by a geometric mean of 40% (95% CI 29%-63%), and 73% (95% CI 57%-85%) of women had tumors with decreased proliferation after 7 days of tamoxifen (p=0.0001 by paired t-test). No correlation was seen between the change in Ki-67 and change in FACT-ES or MENQoL scores. Women reported minimal to no bother from psychosocial or physical symptoms at baseline or on the day of surgery. Expression level of individual proliferation genes did not change after 7 days of tamoxifen.

CONCLUSION: Seven days of tamoxifen showed a similar relative decrease in the Ki67 proliferation index as that reported for longer courses. Therefore, short window of opportunity trials can be informative.

Citation Format: Cohen AL, Factor RE, Mooney K, Wade M, Serpico V, Salama M, Nelson E, Porretta J, Matsen C, Ostrander E, Bernard P, Boucher K, Neumayer L. PowerPIINC trial: Changes in tumor proliferation index and quality of life with 7 days of preoperative tamoxifen [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-10-05.

Quality specifications in postgraduate medical e-learning: an integrative literature review leading to a postgraduate medical e-learning model

BACKGROUND

E-learning is driving major shifts in medical education. Prioritizing learning theories and quality models improves the success of e-learning programs. Although many e-learning quality standards are available, few are focused on postgraduate medical education.

METHODS

We conducted an integrative review of the current postgraduate medical e-learning literature to identify quality specifications. The literature was thematically organized into a working model.

RESULTS

Unique quality specifications (n = 72) were consolidated and re-organized into a six-domain model that we called the Postgraduate Medical E-learning Model (Postgraduate ME Model). This model was partially based on the ISO-19796 standard, and drew on cognitive load multimedia principles. The domains of the model are preparation, software design and system specifications, communication, content, assessment, and maintenance.

CONCLUSION

This review clarified the current state of postgraduate medical e-learning standards and specifications. It also synthesized these specifications into a single working model. To validate our findings, the next-steps include testing the Postgraduate ME Model in controlled e-learning settings.

Obesity Management: Clinical Review and Update of the Pharmacologic Treatment Options

The toolbox of medications available for medical weight management is more robust than ever and includes a wide variety of mechanisms of actions and options for patients.

Gender effects in alcohol dependence: an fMRI pilot study examining affective processing

BACKGROUND

Alcohol dependence (AD) has global effects on brain structure and function, including frontolimbic regions regulating affective processing. Preliminary evidence suggests alcohol blunts limbic response to negative affective stimuli and increases activation to positive affective stimuli. Subtle gender differences are also evident during affective processing.

METHODS

Fourteen abstinent AD individuals (8 F, 6 M) and 14 healthy controls (9 F, 5 M), ages 23 to 60, were included in this facial affective processing functional magnetic resonance imaging pilot study. Whole-brain linear regression analyses were performed, and follow-up analyses examined whether AD status significantly predicted depressive symptoms and/or coping.

RESULTS

Fearful Condition-The AD group demonstrated reduced activation in the right medial frontal gyrus, compared with controls. Gender moderated the effects of AD in bilateral inferior frontal gyri. Happy Condition-AD individuals had increased activation in the right thalamus. Gender moderated the effects of AD in the left caudate, right middle frontal gyrus, left paracentral lobule, and right lingual gyrus. Interactive AD and gender effects for fearful and happy faces were such that AD men activated more than control men, but AD women activated less than control women. Enhanced coping was associated with greater activation in right medial frontal gyrus during fearful condition in AD individuals.

CONCLUSIONS

Abnormal affective processing in AD may be a marker of alcoholism risk or a consequence of chronic alcoholism. Subtle gender differences were observed, and gender moderated the effects of AD on neural substrates of affective processing. AD individuals with enhanced coping had brain activation patterns more similar to controls. Results help elucidate the effects of alcohol, gender, and their interaction on affective processing.

Inhibition of Wild-Type p53-Expressing AML by the Novel Small Molecule HDM2 Inhibitor CGM097

The tumor suppressor p53 is a key regulator of apoptosis and functions upstream in the apoptotic cascade by both indirectly and directly regulating Bcl-2 family proteins. In cells expressing wild-type (WT) p53, the HDM2 protein binds to p53 and blocks its activity. Inhibition of HDM2:p53 interaction activates p53 and causes apoptosis or cell-cycle arrest. Here, we investigated the ability of the novel HDM2 inhibitor CGM097 to potently and selectively kill WT p53-expressing AML cells. The antileukemic effects of CGM097 were studied using cell-based proliferation assays (human AML cell lines, primary AML patient cells, and normal bone marrow samples), apoptosis, and cell-cycle assays, ELISA, immunoblotting, and an AML patient-derived in vivo mouse model. CGM097 potently and selectively inhibited the proliferation of human AML cell lines and the majority of primary AML cells expressing WT p53, but not mutant p53, in a target-specific manner. Several patient samples that harbored mutant p53 were comparatively unresponsive to CGM097. Synergy was observed when CGM097 was combined with FLT3 inhibition against oncogenic FLT3-expressing cells cultured both in the absence as well as the presence of cytoprotective stromal-secreted cytokines, as well as when combined with MEK inhibition in cells with activated MAPK signaling. Finally, CGM097 was effective in reducing leukemia burden in vivo. These data suggest that CGM097 is a promising treatment for AML characterized as harboring WT p53 as a single agent, as well as in combination with other therapies targeting oncogene-activated pathways that drive AML.

Future fire emissions associated with projected land use change in Sumatra

Indonesia has experienced rapid land use change over the last few decades as forests and peatswamps have been cleared for more intensively managed land uses, including oil palm and timber plantations. Fires are the predominant method of clearing and managing land for more intensive uses, and the related emissions affect public health by contributing to regional particulate matter and ozone concentrations and adding to global atmospheric carbon dioxide concentrations. Here, we examine emissions from fires associated with land use clearing and land management on the Indonesian island of Sumatra and the sensitivity of this fire activity to interannual meteorological variability. We find ~80% of 2005-2009 Sumatra emissions are associated with degradation or land use maintenance instead of immediate land use conversion, especially in dry years. We estimate Sumatra fire emissions from land use change and maintenance for the next two decades with five scenarios of land use change, the Global Fire Emissions Database Version 3, detailed 1-km2 land use change maps, and MODIS fire radiative power observations. Despite comprising only 16% of the original study area, we predict that 37-48% of future Sumatra emissions from land use change will occur in fuel-rich peatswamps unless this land cover type is protected effectively. This result means that the impact of fires on future air quality and climate in Equatorial Asia will be decided in part by the conservation status given to the remaining peatswamps on Sumatra. Results from this article will be implemented in an atmospheric transport model to quantify the public health impacts from the transport of fire emissions associated with future land use scenarios in Sumatra.

Speciation and localization of Zn in the hyperaccumulator Sedum alfredii by extended X-ray absorption fine structure and micro-X-ray fluorescence

Differences in metal homeostasis among related plant species can give important information of metal hyperaccumulation mechanisms. Speciation and distribution of Zn were investigated in a hyperaccumulating population of Sedum alfredii by using extended X-ray absorption fine structure and micro-synchrotron X-ray fluorescence (μ-XRF), respectively. The hyperaccumulator uses complexation with oxygen donor ligands for Zn storage in leaves and stems, and variations in the Zn speciation was noted in different tissues. The dominant chemical form of Zn in leaves was most probably a complex with malate, the most prevalent organic acid in S. alfredii leaves. In stems, Zn was mainly associated with malate and cell walls, while Zn-citrate and Zn-cell wall complexes dominated in the roots. Two-dimensional μ-XRF images revealed age-dependent differences in Zn localization in S. alfredii stems and leaves. In old leaves of S. alfredii, Zn was high in the midrib, margin regions and the petiole, whereas distribution of Zn was essentially uniform in young leaves. Zinc was preferentially sequestered by cells near vascular bundles in young stems, but was highly localized to vascular bundles and the outer cortex layer of old stems. The results suggest that tissue- and age-dependent variations of Zn speciation and distribution occurred in the hyperaccumulator S. alfredii, with most of the Zn complexed with malate in the leaves, but a shift to cell wall- and citric acid-Zn complexes during transportation and storage in stems and roots. This implies that biotransformation in Zn complexation occurred during transportation and storage processes in the plants of S. alfredii.

Upregulation of IGF1R by mutant RAS in leukemia and potentiation of RAS signaling inhibitors by small-molecule inhibition of IGF1R

PURPOSE

Activating mutations in the RAS oncogene occur frequently in human leukemias. Direct targeting of RAS has proven to be challenging, although targeting of downstream RAS mediators, such as MEK, is currently being tested clinically. Given the complexity of RAS signaling, it is likely that combinations of targeted agents will be more effective than single agents.

EXPERIMENTAL DESIGN

A chemical screen using RAS-dependent leukemia cells was developed to identify compounds with unanticipated activity in the presence of an MEK inhibitor and led to identification of inhibitors of IGF1R. Results were validated using cell-based proliferation, apoptosis, cell-cycle, and gene knockdown assays; immunoprecipitation and immunoblotting; and a noninvasive in vivo bioluminescence model of acute myeloid leukemia (AML).

RESULTS

Mechanistically, IGF1R protein expression/activity was substantially increased in mutant RAS-expressing cells, and suppression of RAS led to decreases in IGF1R. Synergy between MEK and IGF1R inhibitors correlated with induction of apoptosis, inhibition of cell-cycle progression, and decreased phospho-S6 and phospho-4E-BP1. In vivo, NSG mice tail veins injected with OCI-AML3-luc+ cells showed significantly lower tumor burden following 1 week of daily oral administration of 50 mg/kg NVP-AEW541 (IGF1R inhibitor) combined with 25 mg/kg AZD6244 (MEK inhibitor), as compared with mice treated with either agent alone. Drug combination effects observed in cell-based assays were generalized to additional mutant RAS-positive neoplasms.

CONCLUSIONS

The finding that downstream inhibitors of RAS signaling and IGF1R inhibitors have synergistic activity warrants further clinical investigation of IGF1R and RAS signaling inhibition as a potential treatment strategy for RAS-driven malignancies.

Crucial role of Plexin C1 for pulmonary inflammation and survival during lung injury

Acute pulmonary inflammation during lung injury is initiated by the migration of neutrophils into the alveolar space. The severity of these inflammatory changes within the pulmonary tissue determines the severity of lung injury and ultimately patient outcome. Recent work has demonstrated that the guidance protein Semaphorin 7A propagates the infiltration of neutrophils into an hypoxic tissue site, yet the role of its target receptor Plexin C1 (PLXNC1) during lung injury is to date unknown. We demonstrate here that PLXNC1(+) neutrophils are present within the alveolar space and that PLXNC1 is induced in vitro and in vivo during lung injury. In a model of high-pressure ventilation PLXNC1(-/-) animals show decreased signs of alveolar inflammation and improved survival compared with wild-type controls. Studies employing chimeric animals identified the hematopoietic expression of PLXNC1 to be of crucial importance for the observed results. Functional inhibition of PLXNC1 resulted in improved survival and ameliorated the signs of inflammation within the lung. Furthermore, the injection of a peptide binding to PLXNC1 resulted in improved survival and attenuated pulmonary inflammation. As such we demonstrate here, that previously unknown PLXNC1 holds significant importance for degree of pulmonary inflammation and determines outcome during experimental lung injury.

Identification of Wee1 as a novel therapeutic target for mutant RAS-driven acute leukemia and other malignancies

Direct targeting of rat sarcoma (RAS), which is frequently mutated, has proven to be challenging, and inhibition of individual downstream RAS mediators has resulted in limited clinical efficacy. We designed a chemical screen to identify compounds capable of potentiating mammalian target of rapamycin (mTOR) inhibition in mutant RAS-positive leukemia, and identified a Wee1 inhibitor. Synergy was observed in both mutant neuroblastoma RAS viral oncogene homolog (NRAS)- and mutant kirsten RAS viral oncogene homolog (KRAS)-positive acute myelogenous leukemia (AML) cell lines and primary patient samples. The observed synergy enhanced dephosphorylation of AKT, 4E-binding protein 1 and s6 kinase, and correlated with increased apoptosis. The specificity of Wee1 as the target of MK-1775 was validated by Wee1 knockdown, as well as partial reversal of drug combination-induced apoptosis by a cyclin-dependent kinase 1 (CDK1) inhibitor. Importantly, we also extended our findings to other mutant RAS-expressing malignancies, including mutant NRAS-positive melanoma, and mutant KRAS-positive colorectal cancer, pancreatic cancer and lung cancer. We observed favorable responses with combined Wee1/mTOR inhibition in human cancer cell lines from multiple malignancies, and inhibition of tumor growth in in vivo models of mutant KRAS lung cancer and leukemia. The present study introduces for the first time Wee1 inhibition combined with mTOR inhibition as a novel therapeutic strategy for the selective treatment of mutant RAS-positive leukemia and other mutant RAS-expressing malignancies.

Abstract OT3-2-02: PreOperative window of endocrine therapy provides information to increase compliance: POWER PIINC: A feasibility study

Background: The addition of systemic therapy to the surgical treatment of breast cancer has improved survival of patients. A mainstay of systemic therapy in the setting of hormone receptor positive breast cancer is endocrine therapy. Despite the known advantages, the compliance with short and long term systemic endocrine therapy is less than ideal. Several studies report significant rates of non-compliance with endocrine therapy, either in patients never starting the medication or not completing the recommended multi-year course. It is estimated that as many as 10% of patients per year discontinue their therapy. We wondered why women would forgo such an important part of their treatment and how we might intervene to improve compliance. Using information gleaned from POWER PIINC, we hope to design a behavioral intervention study to see if the patient knowing her tumor's preoperative response to endocrine therapy will improve long term compliance. In order to do such a study we would need to define the minimal length of preoperative endocrine therapy needed to detect measurable changes in the tumor.

After 14 days of endocrine therapy, significant decreases in Ki67 can be seen in most hormone sensitive breast cancers. In fact two current studies are using this information (POETIC and ADAPT trials). Both of these trials are being conducted outside of the U.S. where operative therapy does not typically occur within a week or two of seeing the surgeon. POWER PIINC is a feasibility study to determine if we can detect changes in Ki67 with only 7 days of therapy. The results of POWER PIINC will inform the behavioral intervention trial.

Trial Design: This is a prospective, single-arm feasibility study. Participants take tamoxifen for 7 days prior to surgery. Ki67 is measured pre (core biopsy) and post (surgical specimen) tamoxifen.

Eligibility critieria: Non-pregnant women age 18 or older with a hormone positive (&gt;1% ER or PR) clinical Stage 1 or 2 breast cancer who are candidates for surgical therapy of their breast cancer. No concurrent CYP2D6 inhibitors or other contraindications to tamoxifen.

Specific Aims:

Primary Objective:

Demonstrate a significant reduction in Ki67 expression in tumors with 7 days of pre-surgical tamoxifen.

Secondary Objectives:

- Evaluate symptom patterns from baseline through 18 months of follow-up (presence, severity, and bother)

-Evaluate 18-month endocrine therapy adherence

-Evaluate change in attitude regarding endocrine therapy

-Evaluate correlation between changes in Ki67 expression and symptom scores

-Evaluate additional changes in proliferative markers (subset of PAM 50)

Statistical Methods: A one-sample t-test will be applied to the log-ratio of Ki67 at resection to pre therapy. If this ratio is not normally distributed we will use a non-parametric Wilcoxon test. Secondary objectives will be analyzed using a variety of appropriate statistical tests.

Accrual: Target accrual is 52 patients over 18 months. We opened this study in August of 2012. To date (9 months) we have accrued 23 patients.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT3-2-02.

Evaluating the return in ecosystem services from investment in public land acquisitions

We evaluate the return on investment (ROI) from public land conservation in the state of Minnesota, USA. We use a spatially-explicit modeling tool, the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST), to estimate how changes in land use and land cover (LULC), including public land acquisitions for conservation, influence the joint provision and value of multiple ecosystem services. We calculate the ROI of a public conservation acquisition as the ratio of the present value of ecosystem services generated by the conservation to the cost of the conservation. For the land scenarios analyzed, carbon sequestration services generated the greatest benefits followed by water quality improvements and recreation opportunities. We found ROI values ranged from 0.21 to 5.28 depending on assumptions about future land use change, service values, and discount rate. Our study suggests conservation is a good investment as long as investments are targeted to areas with low land costs and high service values.

Abstract 1376: Exercise alters breast cancer phenotype through distinct reductions in host-derived proinflammatory growth factor ligands

It is becoming increasingly recognized that host (systemic) and tumor cell release of proinflammatory growth factors are critical determinants of cancer progression and therapeutic response in patients with solid tumors. Thus, strategies that can attenuate systemic and/or tumor production of proinflammatory growth factors may offer an effective approach to improve therapeutic outcomes following a cancer diagnosis. The present study tests the central hypothesis that exercise modulates systemic levels of key growth factor ligands that, in turn, inhibit the activity of critical downstream cell signaling pathways to effectively inhibit tumor progression. To address this question, we took advantage of sera collected from a clinical trial examining the efficacy of supervised exercise training, relative to sedentary control, in patients with early or advanced solid tumors. Multiplex ELISA analysis showed that exercising patients (N=23) had significant reductions in circulating concentrations of interleukin (IL)-4, MIP1-β (macrophage inflammatory protein-1β), vascular endothelial growth factor (VEGF), tumor necrosis factor-alpha (TNF-α), and hepatocyte growth factor (HGF) in comparison with patients randomized to sedentary control (N=21). Exposure of estrogen receptor positive (ER+) and Triple-Negative (ER-/PR-/HER2-) distinct human breast cancer cell lines (MCF-7 and MDA-MB-231) to serum from exercised breast cancer patients led to marked alterations in cellular phenotype as shown by increases in proliferation, migration, and apoptosis, compared with exposure to serum from control patients. In vitro ‘add-back’ experiments using recombinant growth factors in concentrations consistent with that observed in the clinical trial, revealed that HGF produced similar alterations in tumor proliferation and apoptosis as that observed with serum from exercising patients. Co-culturing of human breast cancer cells with exercise serum and a neutralizing antibody against HGF, led to increases in proliferation and decreases in apoptosis in comparison to exercise serum alone. These results suggest that growth factor ligand deprivation may play a critical role in mediating the effects of exercise on tumor cellular phenotype. As such, our findings may provide initial insight into the potential mechanisms underlying recent observations showing higher levels of exercise correlate with more favorable disease outcomes in early breast cancer patients. More generally, this study indicates the widespread potential of exercise to modulate growth factor-driven signaling and by extension, tumor progression and possibly innate or acquired resistance to therapy.

Citation Format: Oliver Glass, Brant A. Inman, Kerry S. Courneya, John R. Mackey, Erik Nelson, Zachary Hartman, Lee W. Jones. Exercise alters breast cancer phenotype through distinct reductions in host-derived proinflammatory growth factor ligands. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1376. doi:10.1158/1538-7445.AM2013-1376

L-methylfolate as adjunctive therapy for SSRI-resistant major depression: results of two randomized, double-blind, parallel-sequential trials

OBJECTIVE

The authors conducted two multicenter sequential parallel comparison design trials to investigate the effect of L-methylfolate augmentation in the treatment of major depressive disorder in patients who had a partial response or no response to selective serotonin reuptake inhibitors (SSRIs).

METHOD

In the first trial, 148 outpatients with SSRI-resistant major depressive disorder were enrolled in a 60-day study divided into two 30-day periods. Patients were randomly assigned, in a 2:3:3 ratio, to receive L-methylfolate for 60 days (7.5 mg/day for 30 days followed by 15 mg/day for 30 days), placebo for 30 days followed by L-methylfolate (7.5 mg/day) for 30 days, or placebo for 60 days. SSRI dosages were kept constant throughout the study. In the second trial, with 75 patients, the design was identical to the first, except that the l-methylfolate dosage was 15 mg/day during both 30-day periods.

RESULTS

In the first trial, no significant difference was observed in outcomes between the treatment groups. In the second trial, adjunctive L-methylfolate at 15 mg/day showed significantly greater efficacy compared with continued SSRI therapy plus placebo on both primary outcome measures (response rate and degree of change in depression symptom score) and two secondary outcome measures of symptom severity. The number needed to treat for response was approximately six in favor of adjunctive L-methylfolate at 15 mg/day. L-Methylfolate was well tolerated, with rates of adverse events no different from those reported with placebo.

CONCLUSIONS

Adjunctive L-methylfolate at 15 mg/day may constitute an effective, safe, and relatively well tolerated treatment strategy for patients with major depressive disorder who have a partial response or no response to SSRIs.