A neoteric antibacterial ceria-silver nanozyme for abiotic surfaces.

Community-associated and hospital-acquired infections caused by bacteria continue to yield major global challenges to human health. Bacterial contamination on abiotic surfaces is largely spread via high-touch surfaces and contemporary standard disinfection practices show limited efficacy, resulting in unsatisfactory therapeutic outcomes. New strategies that offer non-specific and broad protection are urgently needed. Herein, we report our novel ceria-silver nanozyme engineered at a molar ratio of 5:1 and with a higher trivalent (Ce3+) surface fraction. Our results reveal potent levels of surface catalytic activity on both wet and dry surfaces, with rapid, and complete eradication of Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin resistant S. aureus, in both planktonic and biofilm form. Preferential electrostatic adherence of anionic bacteria to the cationic nanozyme surface leads to a catastrophic loss in both aerobic and anaerobic respiration, DNA damage, osmodysregulation, and finally, programmed bacterial lysis. Our data reveal several unique mechanistic avenues of synergistic ceria-Ag efficacy. Ag potentially increases the presence of Ce3+ sites at the ceria-Ag interface, thereby facilitating the formation of harmful H2O2, followed by likely permeation across the cell wall. Further, a weakened Ag-induced Ce-O bond may drive electron transfer from the Ec band to O2, thereby further facilitating the selective reduction of O2 toward H2O2 formation. Ag destabilizes the surface adsorption of molecular H2O2, potentially leading to higher concentrations of free H2O2 adjacent to bacteria. To this end, our results show that H2O2 and/or NO/NO2-/NO3- are the key liberators of antibacterial activity, with a limited immediate role being offered by nanozyme-induced ROS including O2•- and OH•, and likely other light-activated radicals. A mini-pilot proof-of-concept study performed in a pediatric dental clinic setting confirms residual, and continual nanozyme antibacterial efficacy over a 28-day period. These findings open a new approach to alleviate infections caused by bacteria for use on high-touch hard surfaces.

A Multifunctional Therapeutic Strategy Using P7C3 as A Countermeasure Against Bone Loss and Fragility in An Ovariectomized Rat Model of Postmenopausal Osteoporosis.

By 2060, an estimated one in four Americans will be elderly. Consequently, the prevalence of osteoporosis and fragility fractures will also increase. Presently, no available intervention definitively prevents or manages osteoporosis. This study explores whether Pool 7 Compound 3 (P7C3) reduces progressive bone loss and fragility following the onset of ovariectomy (OVX)-induced osteoporosis. Results confirm OVX-induced weakened, osteoporotic bone together with a significant gain in adipogenic body weight. Treatment with P7C3 significantly reduced osteoclastic activity, bone marrow adiposity, whole-body weight gain, and preserved bone area, architecture, and mechanical strength. Analyses reveal significantly upregulated platelet derived growth factor-BB and leukemia inhibitory factor, with downregulation of interleukin-1 R6, and receptor activator of nuclear factor kappa-B (RANK). Together, proteomic data suggest the targeting of several key regulators of inflammation, bone, and adipose turnover, via transforming growth factor-beta/SMAD, and Wingless-related integration site/be-catenin signaling pathways. To the best of the knowledge, this is first evidence of an intervention that drives against bone loss via RANK. Metatranscriptomic analyses of the gut microbiota show P7C3 increased Porphyromonadaceae bacterium, Candidatus Melainabacteria, and Ruminococcaceae bacterium abundance, potentially contributing to the favorable inflammatory, and adipo-osteogenic metabolic regulation observed. The results reveal an undiscovered, and multifunctional therapeutic strategy to prevent the pathological progression of OVX-induced bone loss.

Sphingolipid-Induced Bone Regulation and Its Emerging Role in Dysfunction Due to Disease and Infection.

The human skeleton is a metabolically active system that is constantly regenerating via the tightly regulated and highly coordinated processes of bone resorption and formation. Emerging evidence reveals fascinating new insights into the role of sphingolipids, including sphingomyelin, sphingosine, ceramide, and sphingosine-1-phosphate, in bone homeostasis. Sphingolipids are a major class of highly bioactive lipids able to activate distinct protein targets including, lipases, phosphatases, and kinases, thereby conferring distinct cellular functions beyond energy metabolism. Lipids are known to contribute to the progression of chronic inflammation, and notably, an increase in bone marrow adiposity parallel to elevated bone loss is observed in most pathological bone conditions, including aging, rheumatoid arthritis, osteoarthritis, and osteomyelitis. Of the numerous classes of lipids that form, sphingolipids are considered among the most deleterious. This review highlights the important primary role of sphingolipids in bone homeostasis and how dysregulation of these bioactive metabolites appears central to many chronic bone-related diseases. Further, their contribution to the invasion, virulence, and colonization of both viral and bacterial host cell infections is also discussed. Many unmet clinical needs remain, and data to date suggest the future use of sphingolipid-targeted therapy to regulate bone dysfunction due to a variety of diseases or infection are highly promising. However, deciphering the biochemical and molecular mechanisms of this diverse and extremely complex sphingolipidome, both in terms of bone health and disease, is considered the next frontier in the field.

Young people's priorities for the self-management of distress after stoma surgery due to inflammatory bowel disease: A consensus study using online nominal group technique.

INTRODUCTION: The aim of this study was to gain consensus among young people with a stoma due to inflammatory bowel disease (IBD) on the priorities for the content of an intervention for the self-management of stoma-related distress. The current identification and management of distress in young people with a stoma is often suboptimal in clinical settings and there is a need for improved support resources. METHODS: Two consensus group meetings were carried out via online video conferencing, using nominal group technique. Participants generated, rated on a Likert scale and discussed, topics for inclusion in a future self-management intervention. RESULTS: Nineteen young people, aged 19-33, with a stoma due to IBD took part in one of two group meetings. Participants were located across England, Scotland, and Northern Ireland. Twenty-nine topics were generated by participants, seven of which reached consensus of ≥80%, that is, a mean of ≥5.6 on a 7-point Likert scale. These were: receiving advice from young people with lived experience of stoma surgery; advice on/addressing concerns about romantic relationships, sex and intimacy; information about fertility and pregnancy related to stoma surgery; stoma 'hacks', for example, useful everyday tips regarding clothing, making bag changes easier and so forth; reflecting on and recognising own emotional response to surgery; tips on managing the stoma during the night; and processing trauma related to the illness and surgery journey. CONCLUSIONS: Findings extend previous research on young people's experiences of stoma surgery, by generating consensus on young people's priorities for managing distress related to surgery and living with a stoma. These priorities include topics not previously reported in the literature, including the need for information about fertility and pregnancy. Findings will inform the development of a self-management resource for young people with an IBD stoma and have relevance for the clinical management of stoma-related distress in this population. PATIENT OR PUBLIC CONTRIBUTION: Three patient contributors are co-authors on this paper, having contributed to the study design, interpretation of results and writing of the manuscript. The study's Patient and Public Involvement and Engagement advisory group also had an integral role in the study. They met with the research team for four 2-h virtual meetings, giving input on the aims and purpose of the study, recruitment methods, and interpretation of findings. The group also advised on the age range for participants. The views of young people with a stoma are the central component of the study reported in this paper, which aims to gain consensus among young people with an IBD stoma on their priorities for the content of a resource to self-manage distress related to stoma surgery.

Extracellular Proteins Isolated from L. acidophilus as an Osteomicrobiological Therapeutic Agent to Reduce Pathogenic Biofilm Formation, Regulate Chronic Inflammation, and Augment Bone Formation In Vitro.

Periprosthetic joint infection (PJI) is a challenging complication that can occur following joint replacement surgery. Efficacious strategies to prevent and treat PJI and its recurrence remain elusive. Commensal bacteria within the gut convey beneficial effects through a defense strategy named "colonization resistance" thereby preventing pathogenic infection along the intestinal surface. This blueprint may be applicable to PJI. The aim is to investigate Lactobacillus acidophilus spp. and their isolated extracellular-derived proteins (LaEPs) on PJI-relevant Staphylococcus aureus, methicillin-resistant S. aureus, and Escherichia coli planktonic growth and biofilm formation in vitro. The effect of LaEPs on cultured macrophages and osteogenic, and adipogenic human bone marrow-derived mesenchymal stem cell differentiation is analyzed. Data show electrostatically-induced probiotic-pathogen species co-aggregation and pathogenic growth inhibition together with LaEP-induced biofilm prevention. LaEPs prime macrophages for enhanced microbial phagocytosis via cathepsin K, reduce lipopolysaccharide-induced DNA damage and receptor activator nuclear factor-kappa B ligand expression, and promote a reparative M2 macrophage morphology under chronic inflammatory conditions. LaEPs also significantly augment bone deposition while abating adipogenesis thus holding promise as a potential multimodal therapeutic strategy. Proteomic analyses highlight high abundance of lysyl endopeptidase, and urocanate reductase. Further, in vivo analyses are warranted to elucidate their role in the prevention and treatment of PJIs.

Evaluation of a person-centred, nurse-led model of care delivering hepatitis C testing and treatment in priority settings: a mixed-methods evaluation of the Tasmanian Eliminate Hepatitis C Australia Outreach Project, 2020-2022.

INTRODUCTION: Australia has experienced sustained reductions in hepatitis C testing and treatment and may miss its 2030 elimination targets. Addressing gaps in community-based hepatitis C prescribing in priority settings that did not have, or did not prioritise, hepatitis C testing and treatment care pathways is critical. METHODS: The Tasmanian Eliminate Hepatitis C Australia Outreach Project delivered a nurse-led outreach model of care servicing hepatitis C priority populations in the community through the Tasmanian Statewide Sexual Health Service, supported by the Eliminating Hepatitis C Australia partnership. Settings included alcohol and other drug services, needle and syringe programs and mental health services. The project provided clients with clinical care across the hepatitis C cascade of care, including testing, treatment, and post-treatment support and hepatitis C education for staff. RESULTS: Between July 2020 and July 2022, a total of 43 sites were visited by one Clinical Nurse Consultant. There was a total of 695 interactions with clients across 219 days of service delivery by the Clinical Nurse Consultant. A total of 383 clients were tested for hepatitis C (antibody, RNA, or both). A total of 75 clients were diagnosed with hepatitis C RNA, of which 95% (71/75) commenced treatment, 83% (62/75) completed treatment and 52% (39/75) received a negative hepatitis C RNA test at least 12 weeks after treatment completion. CONCLUSIONS: Providing outreach hepatitis C services in community-based services was effective in engaging people living with and at-risk of hepatitis C, in education, testing, and care. Nurse-led, person-centred care was critical to the success of the project. Our evaluation underscores the importance of employing a partnership approach when delivering hepatitis C models of care in community settings, and incorporating workforce education and capacity-building activities when working with non-specialist healthcare professionals.

Healthcare professionals' priorities for training to identify and manage distress experienced by young people with a stoma due to inflammatory bowel disease: a consensus study using online nominal group technique.

OBJECTIVES: Young people with a stoma due to inflammatory bowel disease (IBD) commonly experience distress; however, this is not always well managed in clinical settings. More effective support may/is likely to reduce the possibility of individuals experiencing sustained distress, which may engender depression or anxiety. This study aimed to gain consensus among a multidisciplinary group of healthcare professionals (HCPs) on priorities for training in the identification and management of distress in this population. One of the authors is a young person with a stoma. DESIGN: Participants were recruited through Twitter (X) and the researchers' clinical/research contacts. Two consensus group meetings were conducted using Nominal Group Technique, involving participants generating, discussing and rating on a Likert scale, topics for inclusion in an HCP training package. SETTING: Online video conferencing. Participants were located across England, with one based in the USA. PARTICIPANTS: Nineteen HCPs participated: three general practitioners, three stoma nurses, two IBD nurses, nine clinical psychologists and two gastroenterologists. RESULTS: Twenty-five topics were generated by participants; 19 reached consensus of ≥80%, that is, a mean of ≥5.6 on a 7-point Likert scale. These included: recognising and validating different levels of, and variation in, distress; tackling stigma and normalising having a stoma; everyday practicalities of stoma management, including food and sleep; opening and holding conversations about stoma-related distress; considering the impact of different cultural beliefs on adaptation after stoma surgery; training in simple techniques for gauging the patient's distress during clinical encounters; having conversations about body image; and myth-busting common fears, such as odour. CONCLUSIONS: This study is the first to identify HCP training priorities for managing stoma-related distress in young people. Consensus was reached for 19 topics, reflecting the varied needs of young people with a stoma. Findings will inform development of a training package for HCPs treating young people with IBD and a stoma.

How Could Sensor-Based Measurement of Physical Activity Be Used in Cardiovascular Healthcare?

Physical activity and cardiovascular disease (CVD) are intimately linked. Low levels of physical activity increase the risk of CVDs, including myocardial infarction and stroke. Conversely, when CVD develops, it often reduces the ability to be physically active. Despite these largely understood relationships, the objective measurement of physical activity is rarely performed in routine healthcare. The ability to use sensor-based approaches to accurately measure aspects of physical activity has the potential to improve many aspects of cardiovascular healthcare across the spectrum of healthcare, from prediction, prevention, diagnosis, and treatment to disease monitoring. This review discusses the potential of sensor-based measurement of physical activity to augment current cardiovascular healthcare. We highlight many factors that should be considered to maximise the benefit and reduce the risks of such an approach. Because the widespread use of such devices in society is already a reality, it is important that scientists, clinicians, and healthcare providers are aware of these considerations.

Self-directed self-management interventions to prevent or address distress in young people with long-term physical conditions: A rapid review.

BACKGROUND: Comorbid distress in adolescents and young adults with physical long-term conditions (LTCs) is common but can be difficult to identify and manage. Self-directed self-management interventions to reduce distress and improve wellbeing may be beneficial. It is unknown, however, which intervention characteristics are successful in supporting young people. This rapid review aimed to identify characteristics of self-directed self-management interventions that aimed, in whole or part, to address distress, wellbeing or self-efficacy in this population. METHODS: A systematic search was conducted for relevant controlled studies in six databases. Data on study settings, population, intervention characteristics, outcome measures, process measures and summary effects were extracted. The risk of bias was assessed using the Cochrane Risk of Bias tool v1, and the strength of evidence was rated (informed by Grading of Recommendations, Assessment, Development and Evaluations). Patient and public involvement members supported the review process, including interpretation of results. The rapid review was registered with PROSPERO (ID: CRD42021285867). RESULTS: Fourteen studies were included, all of which were randomised trials. Heterogeneity was identified in the health conditions targeted; type of intervention; outcome measures; duration of intervention and follow-up. Three had distress, wellbeing or self-efficacy as their primary outcome. Four modes of delivery were identified across interventions-websites, smartphone applications, text messages and workbooks; and within these, 38 individual components. Six interventions had a significant benefit in mental health, wellbeing or self-efficacy; however, intervention characteristics were similar for beneficial and non-beneficial interventions. CONCLUSIONS: There is a paucity of interventions directly targeting distress and wellbeing in young people with physical LTCs. In those identified, the heterogeneity of interventions and study design makes it difficult to identify which characteristics result in positive outcomes. We propose the need for high-quality, evidence-based self-management interventions for this population; including (1) more detailed reporting of intervention design, content and delivery; (2) robust process evaluation; (3) a core outcome set for measuring mental health and wellbeing for self-management interventions and (4) consistency in follow up periods. PUBLIC CONTRIBUTION: Seven young people with an LTC were involved throughout the rapid review, from the development of the review protocol where they informed the focus and aims, with a central role in the interpretation of findings.

The interRAI COVID-19 vulnerability screener: Results of a health surveillance initiative for vulnerable adults in the community during the COVID-19 pandemic.

During the pandemic, the interRAI COVID-19 Vulnerability Screener (CVS) was used to identify community-dwelling older adults or adults with disabilities at risk of negative outcomes and facilitate triage for follow-up with health/social services. The interRAI CVS, a standardized self-report instrument administered virtually by a lay-person, includes COVID-19-related items and psychosocial and physical vulnerability. Our objective was to describe those assessed and identify sub-groups at highest risk of adverse outcomes. Seven community-based organizations in Ontario, Canada, implemented the interRAI CVS. We used descriptive statistics to report results and created a priority indicator for monitoring and/or intervention based on possible COVID-19 symptoms and psychosocial/physical vulnerabilities. We used logistic regression to examine the association between priority level and risk of poor outcomes using fair/poor self-rated health as a proxy measure. The sample included 942 adults assessed (April-November 2020; mean age=79). About 10% of individuals reported potential COVID-19 symptoms and <1% had a positive COVID-19 test/diagnosis. Of those with psychosocial/physical vulnerabilities (73.1%), most common were depressed mood (20.9%), loneliness (21.6%), and limited access to food/medications (7.5%). Overall, 45.7% had a recent doctor or nurse practitioner visit. Odds of fair/poor self-reported health were highest among those who reported both possible symptoms of COVID-19 and psychosocial/physical vulnerabilities (OR 10.9, 95% CI 5.96-20.12) compared to those with neither symptoms nor psychosocial/physical vulnerabilities. The sample represents a population largely unaffected by COVID-19 itself but with identified vulnerabilities. The interRAI CVS allows community providers to stay connected and obtain a better understanding of vulnerable individuals' needs during the pandemic.

Building blocks of biofilms - an engaging and hands-on microbiology outreach activity for school children and the general public.

Biofilms are naturally occurring communities of micro-organisms, attached to a surface and often embedded in a matrix of self-produced polymeric substances. Biofilms are widely implicated in human infections, particularly on prostheses and medical implants. Such biofilms are difficult to eradicate, often leading to replacement of the prosthesis and resulting in a significant burden to healthcare. Here we present a fun and engaging interactive activity targeted toward primary school/early secondary school children, introducing the concept of natural and healthcare-associated biofilms, using dental plaque as an archetypal example. Dental plaque forms as a result of poor oral/dental hygiene, and develops according to a typical series of defined stages: attachment and adherence to the surface, followed by colonization and maturation of the biofilm structure, and eventually, dispersal. This activity uses dental disclosing tablets to visualize real biofilms (plaque) on the participants teeth, and uses interlocking building-blocks to represent microorganisms, where children build three-dimensional 'biofilms' of varying shapes and structural integrities. Each of the stages of development are discussed in detail, and after building the biofilms, balls of different shapes, sizes and weights can be used as 'antimicrobials' to disrupt the biofilm structure. The outcomes of the activity are to enhance knowledge and general understanding of biofilms; their ubiquitous presence in the natural environment, development, implications in healthcare, and challenges of treatment. The various 'antimicrobial' balls also provide a basis to introduce and discuss drug selection for infections, and the importance of using the correct antimicrobial for different infections to avoid development of resistance.

Promising applications of D-amino acids in periprosthetic joint infection.

Due to the rise in our aging population, a disproportionate demand for total joint arthroplasty (TJA) in the elderly is forecast. Periprosthetic joint infection (PJI) represents one of the most challenging complications that can occur following TJA, and as the number of primary and revision TJAs continues to rise, an increasing PJI burden is projected. Despite advances in operating room sterility, antiseptic protocols, and surgical techniques, approaches to prevent and treat PJI remain difficult, primarily due to the formation of microbial biofilms. This difficulty motivates researchers to continue searching for an effective antimicrobial strategy. The dextrorotatory-isoforms of amino acids (D-AAs) are essential components of peptidoglycan within the bacterial cell wall, providing strength and structural integrity in a diverse range of species. Among many tasks, D-AAs regulate cell morphology, spore germination, and bacterial survival, evasion, subversion, and adhesion in the host immune system. When administered exogenously, accumulating data have demonstrated that D-AAs play a pivotal role against bacterial adhesion to abiotic surfaces and subsequent biofilm formation; furthermore, D-AAs have substantial efficacy in promoting biofilm disassembly. This presents D-AAs as promising and novel targets for future therapeutic approaches. Despite their emerging antibacterial efficacy, their role in disrupting PJI biofilm formation, the disassembly of established TJA biofilm, and the host bone tissue response remains largely unexplored. This review aims to examine the role of D-AAs in the context of TJAs. Data to date suggest that D-AA bioengineering may serve as a promising future strategy in the prevention and treatment of PJI.

Myocarditis following COVID-19 mRNA vaccination.

Messenger RNA vaccines are the main COVID-19 vaccines authorized for use in the United States. Side effects are typically minor and transient. We report a case series of four subjects with an acute myocarditis-like illness following mRNA COVID-19 vaccination who were hospitalized at our hospital in Lubbock, Texas. Three patients were young men who presented with acute chest pain after the second dose of the mRNA-1273 vaccine. Another patient was a 53-year-old white woman who presented with acute left arm pain 3 days after the first dose of the mRNA-1273 vaccine. She was later found to have acute decompensated heart failure, and endomyocardial biopsy revealed eosinophilic injury-mediated myocarditis.

SARS-CoV-2 Positivity in a Combat Sports Bubble.

OBJECTIVE: The objective of this report is to describe a SARS-CoV-2 protocol and subsequent positivity rate for athletes and staff participating in combat sports events. BACKGROUND: Combat sports are among the most challenging to protect against the transmission of communicable diseases. Sports neurologists are often called on to take a leadership role in the safe management of these events. Our team was asked to provide a plan for pre-fight SARS-CoV-2 testing during the recent pandemic. As a result, we were able to successfully host 28 major combat sports events at a single venue with minimal exposure for staff and participants. DESIGN/METHODS: Athletes and staff were tested for the SARS-CoV-2 virus with a PCR method. Samples were obtained via nasal swab upon arrival at the host hotel. All participants were then quarantined until the results were available. Those with negative tests were allowed to resume training in isolated pods. All participants were retested within 72 hours of the event. Those who were positive were quarantined off site for up to 2 weeks. Consultation was provided with an infectious disease specialist via telemedicine. RESULTS: A total of 8,135 tests were performed from July 1, 2020 until April 30, 2021 for the purpose of maintaining a safe venue. A total of 1,649 subjects were tested. There were 42 positive tests that resulted in an overall SARS-CoV-2 positivity rate of 0.516% for these events. CONCLUSIONS: Our sports neurology team was able to design and implement an effective plan to protect combat sports athletes and staff during the SARS-CoV-2 pandemic. This allowed the safe continuation of 28 events. This protocol design can be implemented when dealing with future outbreaks of communicable diseases.

A guide to epidural management.

Epidural analgesia is a key component in the management of inpatient pain relief, particularly in surgical and trauma patients, and those with comorbidities. When used appropriately epidurals can decrease a patient's opiate consumption, as well as reducing the risk of adverse cardiorespiratory outcomes. To non-anaesthetists, or those not versed in their usage, epidurals can appear complex and intimidating, and the potential complications, although rare, can be catastrophic if not picked up on in a timely fashion. This article demystifies the epidural for hospital clinicians, looking at the anatomy and pharmacology, helping to identify patients who may benefit from epidural analgesia, highlighting some common pitfalls and questions posed by nursing staff, and providing a framework via which junior clinicians can detect, manage and appropriately escalate epidural-related problems and complications. Epidural analgesia is an invasive and high-risk intervention; as such it should always be managed by a multidisciplinary team, including anaesthesia and acute pain services.

Development of pharmacy resident leadership skills through creation of a regional ambulatory care forum.

BACKGROUND AND PURPOSE: Action-based leadership activities help refine leadership skills. This paper describes an experiential, longitudinal leadership experience for post-graduate year two (PGY2) pharmacy residents in ambulatory care. EDUCATIONAL ACTIVITY AND SETTING: As part of a leadership and advocacy rotation, two PGY2 ambulatory care pharmacy residents collaborated with a state association, North Carolina Association of Pharmacists, to co-chair a newly formed regional ambulatory care forum in the western part of the state. The residents developed charges for the group, directed and organized the leadership team meetings, moderated the member events of approximately 30 participants, and served as liaisons to the state association and its members. Two residency preceptors who supervised the academic and leadership experiences for the residency program provided oversight for the residents with the forum. Residents completed written and oral self-reflections, received formative feedback from the forum's leadership team and leadership preceptor, participated in a 360-degree leadership evaluation, and received quarterly summative evaluations. FINDINGS: Skills developed included leading a group, event planning, advocacy, networking, communication, professional writing, creating a shared vision, teamwork, and collaboration. SUMMARY: Serving in leadership roles within professional organizations can provide PGY2 pharmacy residents with practical hands-on leadership opportunities to help prepare them for positional and non-positional leadership roles in the future.

Prioritization of Contaminants of Emerging Concern in Wastewater Treatment Plant Discharges Using Chemical:Gene Interactions in Caged Fish.

We examined whether contaminants present in surface waters could be prioritized for further assessment by linking the presence of specific chemicals to gene expression changes in exposed fish. Fathead minnows were deployed in cages for 2, 4, or 8 days at three locations near two different wastewater treatment plant discharge sites in the Saint Louis Bay, Duluth, MN and one upstream reference site. The biological impact of 51 chemicals detected in the surface water of 133 targeted chemicals was determined using biochemical endpoints, exposure activity ratios for biological and estrogenic responses, known chemical:gene interactions from biological pathways and knowledge bases, and analysis of the covariance of ovary gene expression with surface water chemistry. Thirty-two chemicals were significantly linked by covariance with expressed genes. No estrogenic impact on biochemical endpoints was observed in male or female minnows. However, bisphenol A (BPA) was identified by chemical:gene covariation as the most impactful estrogenic chemical across all exposure sites. This was consistent with identification of estrogenic effects on gene expression, high BPA exposure activity ratios across all test sites, and historical analysis of the study area. Gene expression analysis also indicated the presence of nontargeted chemicals including chemotherapeutics consistent with a local hospital waste stream. Overall impacts on gene expression appeared to be related to changes in treatment plant function during rain events. This approach appears useful in examining the impacts of complex mixtures on fish and offers a potential route in linking chemical exposure to adverse outcomes that may reduce population sustainability.

An integrated approach for identifying priority contaminant in the Great Lakes Basin - Investigations in the Lower Green Bay/Fox River and Milwaukee Estuary areas of concern.

Environmental assessment of complex mixtures typically requires integration of chemical and biological measurements. This study demonstrates the use of a combination of instrumental chemical analyses, effects-based monitoring, and bio-effects prediction approaches to help identify potential hazards and priority contaminants in two Great Lakes Areas of Concern (AOCs), the Lower Green Bay/Fox River located near Green Bay, WI, USA and the Milwaukee Estuary, located near Milwaukee, WI, USA. Fathead minnows were caged at four sites within each AOC (eight sites total). Following 4d of in situ exposure, tissues and biofluids were sampled and used for targeted biological effects analyses. Additionally, 4d composite water samples were collected concurrently at each caged fish site and analyzed for 132 analytes as well as evaluated for total estrogenic and androgenic activity using cell-based bioassays. Of the analytes examined, 75 were detected in composite samples from at least one site. Based on multiple analyses, one site in the East River and another site near a paper mill discharge in the Lower Green Bay/Fox River AOC, were prioritized due to their estrogenic and androgenic activity, respectively. The water samples from other sites generally did not exhibit significant estrogenic or androgenic activity, nor was there evidence for endocrine disruption in the fish exposed at these sites as indicated by the lack of alterations in ex vivo steroid production, circulating steroid concentrations, or vitellogenin mRNA expression in males. Induction of hepatic cyp1a mRNA expression was detected at several sites, suggesting the presence of chemicals that activate the aryl hydrocarbon receptor. To expand the scope beyond targeted investigation of endpoints selected a priori, several bio-effects prediction approaches were employed to identify other potentially disturbed biological pathways and related chemical constituents that may warrant future monitoring at these sites. For example, several chemicals such as diethylphthalate and naphthalene, and genes and related pathways, such as cholinergic receptor muscarinic 3 (CHRM3), estrogen receptor alpha1 (esr1), chemokine ligand 10 protein (CXCL10), tumor protein p53 (p53), and monoamine oxidase B (Maob), were identified as candidates for future assessments at these AOCs. Overall, this study demonstrates that a better prioritization of contaminants and associated hazards can be achieved through integrated evaluation of multiple lines of evidence. Such prioritization can guide more comprehensive follow-up risk assessment efforts.