Biodegradation of Surfactant Chemicals in Estuarine and Near Shore Marine Environments of North Carolina

Estuaries are among the most diverse and productive ecosystems on earth. Estuarine and near shore marine environments receive nearly one-third of anthropogenic discharges to surface waters; however, very little is known about the fate of these chemicals in estuarine environments. The fate of cationic, anionic, and nonionic surfactants was studied in estuaries of coastal North Carolina. Radiolabeled chemicals were used to assess respiration, cellular uptake, and residual material in sewage impacted and unimpacted estuaries, and along the horizontal salinity gradient of the estuary. Respiration was the major fate of all compounds, with little incorporation into biomass. Adaptation of the microbial community through previous exposure to the chemicals appears important only for Linear Alkylbenzene Sulfonate; a chemical which also appears not to degrade significantly in marine waters. In some samples, metabolism resulted in a plateau in degradation extent instead of complete or near complete mineralization, which may be the result of formation of recalcitrant metabolic intermediates.Master of Science in Public Healt

Neighborhood Features and Physiological Risk: An Examination of Allostatic Load

Poor neighborhoods may represent a situation of chronic stress, and may therefore be associated with health-related correlates of stress. We examined whether lower neighborhood income would relate to higher allostatic load, or physiological well-being, through psychological, affective, and behavioral pathways. Using data from the Biomarker Project of the Midlife in the United States (MIDUS) study and the 2000 Census, we demonstrated that people living in lower income neighborhoods have higher allostatic load net of individual income. Moreover, findings indicate that this relation is partially accounted for by anxious arousal symptoms, fast food consumption, smoking, and exercise habits

Neighborhood Cohesion and Daily Well-Being: Results from a Diary Study

Neighborly cohesiveness has documented benefits for health. Furthermore, high perceived neighborhood cohesion offsets the adverse health effects of neighborhood socioeconomic adversity. One potential way neighborhood cohesion influences health is through daily stress processes. The current study uses participants (n = 2022, age 30–84 years) from The Midlife in the United States II and the National Study of Daily Experiences II, collected between 2004 and 2006, to examine this hypothesis using a within-person, daily diary design. We predicted that people who perceive high neighborhood cohesion are exposed to fewer daily stressors, such as interpersonal arguments, lower daily physical symptoms and negative affect, and higher daily positive affect. We also hypothesized that perceptions of neighborhood cohesion buffer decline in affective and physical well-being on days when daily stressors do occur. Results indicate that higher perceived neighborhood cohesion predicts fewer self-reported daily stressors, higher positive affect, lower negative affect, and fewer physical health symptoms. High perceived neighborhood cohesion also buffers the effects of daily stressors on negative affect, even after adjusting for other sources of social support. Results from the present study suggest interventions focusing on neighborhood cohesion may result in improved well-being and may minimize the adverse effect of daily stressors

In vivo γ-tocopherol supplementation decreases systemic oxidative stress and cytokine responses of human monocytes in normal and asthmatic subjects

We have recently reported that gamma tocopherol (γT) reduces allergen and zymosan-induced inflammation using rodent models. As an initial step in extending these observations to humans, we conducted an open-label, Phase I dosing study of two doses (one or two capsules/daily for one week) of a gamma tocopherol rich preparation containing 623mg of γ tocopherol, 61.1mg of d-α-tocopherol, 11.1 mg of d-β-tocopherol (11.1mg), and 231 mg of d-σ-tocopherol per capsule. Endpoints for this study include serum levels of 5-nitro-gamma tocopherol, as a marker of oxidative stress, and changes in serum gamma, alpha and delta tocopherol and γ-2′-carboxyethyl-6-hydroxychroman (CEHC) six and 24 hours after the first dose and after 1 week of treatment. To assess biological activity of this treatment, we obtained peripheral blood mononuclear cells at baseline and after 1 week of treatment with 2 capsules of a gamma tocopherol rich preparation/day, and examined the inflammatory cytokine response of these cells in culture to ex-vivo endotoxin/LPS (0.01 ng/ml) challenge. We also monitored a number of safety endpoints to examine how well this preparation is tolerated in 8 normal volunteers (4 allergic and 4 non-allergic) and 8 allergic asthmatics. We further obtained human monocytes from a subset of these volunteers and treated them ex vivo with γT, αT,γ-CEHC and α-CEHC and assessed their actions on LPS induced degradation of IkBα, and JNK signaling and ROS generation. As detailed herein, this open label study demonstrates that gamma tocopherol enriched supplementation decreased systemic oxidative stress, increased serum levels of gamma tocopherol, and inhibited monocyte responses to LPS without any adverse health effects. Further,in vitro treatment of human monocytes with γ-CEHC and α-CEHC inhibits ROS generation and LPS-induced degradation of IκB and JNK activation

Photoaffinity labeling combined with mass spectrometric approaches as a tool for structural proteomics

Protein chemistry, such as crosslinking and photoaffinity labeling, in combination with modern mass spectrometric techniques, can provide information regarding protein-protein interactions beyond that normally obtained from protein identification and characterization studies. While protein crosslinking can make tertiary and quaternary protein structure information available, photoaffinity labeling can be used to obtain structural data about ligand-protein interaction sites, such as oligonucleotide-protein, drug-protein and protein-protein interaction. In this article, we describe mass spectrometry-based photoaffinity labeling methodologies currently used and discuss their current limitations. We also discuss their potential as a common approach to structural proteomics for providing 3D information regarding the binding region, which ultimately will be used for molecular modeling and structure-based drug design

Perceived Neighborhood Cohesion Buffers COVID-19 Impacts on Mental Health in a United States Sample

Objective This study examined whether perceived neighborhood cohesion (the extent to which neighbors trust and count on one another) buffers against the mental health effects of the 2020 COVID-19 pandemic. Methods The XXX University National COVID-19 and Mental Health Study surveyed US adults (N = 3965; M age = 39 years), measuring depressive symptoms, staying home more during than before the 2020 pandemic, and perceived neighborhood cohesion. Results A series of linear regressions indicated that perceiving one\u27s neighborhood as more cohesive was not only associated with fewer depressive symptoms, but also attenuated the relationship between spending more time at home during the pandemic and depressive symptoms. These relationships persisted even after taking into account several individual-level sociodemographic characteristics as well as multiple contextual features, i.e., median household income, population density, and racial/ethnic diversity of the zip codes in which participants resided. Conclusions Neighborhood cohesion may be leveraged to mitigate pandemic impacts on depressive symptoms

Primary structure and cellular localization of callinectin, an antimicrobial peptide from the blue crab

We report the complete amino acid sequence of callinectin, a 32 amino acid, proline-, arginine-rich AMP with four cysteines and having the sequence WNSNRRFRVGRPPVVGRPGCVCFRAPCPCSNY-amide. The primary structure of callinectin is highly similar to arasins, AMPs recently identified in the small spider crab (Hyas araneus). Callinectin exists in three isomers that vary in the functional group on the tryptophan (W) residue. The most prevalent isomer had a hydroxy-N-formylkynurenine group, while the other two isomers had either N-formylkynurenine or hydroxy-tryptophan. Using a sequence highly similar to native callinectin, we chemically synthesized a peptide which we called callinectin-like peptide (CLP). Via immunoelectron microscopy, affinity-purified rabbit antibodies raised to CLP successfully localized the site of callinectin in blue crab hemocytes to the large electron-dense granules that are found primarily in large granule hemocytes

Slate Literary Magazine, 2012-2013

Trinity College\u27s Literary Magazine - student works.https://digitalrepository.trincoll.edu/slate/1000/thumbnail.jp

Combination Treatment with High-Dose Vitamin C and Alpha-Tocopherol does not Enhance Respiratory-Tract Lining Fluid Vitamin C Levels in Asthmatics

Oxidative stress plays a significant role in allergic airway inflammation. Supplementation with alpha-tocopherol (alone or combined with ascorbate/vitamin C) has been assessed as an intervention for allergic airway diseases with conflicting results. Enhancing levels of airway antioxidants with oral supplements has been suggested as an intervention to protect individuals from the effect of inhaled oxidants, although it is unclear whether supplementation changes tocopherol or vitamin C levels in both serum and airway fluids. Our objective was to obtain pilot safety and dosing data from 14 allergic asthmatic volunteers examining the effect of daily combination oral therapy with 500 mg alpha-tocopherol (αT) and 2 g vitamin C for 12 wk. We examined serum and airway fluid and cellular levels of alpha- and gamma-tocopherol (γT) and vitamin C to plan for future studies of these agents in asthma and allergic rhinitis. Six volunteers completed 12 wk of active treatment with αT and vitamin C and 8 completed placebo. Blood and sputum samples were obtained at baseline and at 6 wk and 12 wk of therapy and were analyzed for αT, γT, and vitamin C levels in the serum, sputum supernatant, and sputum cells. Combination treatment increased serum vitamin C and significantly decreased sputum αT and serum γT levels. No changes were found in sputum supernatant or sputum cell vitamin C or serum αT levels in the active treatment group. In conclusion, supplementation with αT and high-dose vitamin C does not augment vitamin C levels in the respiratory-tract lining fluid

TREM2 Lipid Sensing Sustains the Microglial Response in an Alzheimer’s Disease Model

SummaryTriggering receptor expressed on myeloid cells 2 (TREM2) is a microglial surface receptor that triggers intracellular protein tyrosine phosphorylation. Recent genome-wide association studies have shown that a rare R47H mutation of TREM2 correlates with a substantial increase in the risk of developing Alzheimer’s disease (AD). To address the basis for this genetic association, we studied TREM2 deficiency in the 5XFAD mouse model of AD. We found that TREM2 deficiency and haploinsufficiency augment β-amyloid (Aβ) accumulation due to a dysfunctional response of microglia, which fail to cluster around Aβ plaques and become apoptotic. We further demonstrate that TREM2 senses a broad array of anionic and zwitterionic lipids known to associate with fibrillar Aβ in lipid membranes and to be exposed on the surface of damaged neurons. Remarkably, the R47H mutation impairs TREM2 detection of lipid ligands. Thus, TREM2 detects damage-associated lipid patterns associated with neurodegeneration, sustaining the microglial response to Aβ accumulation