Publications by authors named "Ann Smith"

164 Publications

The association between obesity and weight loss after bariatric surgery on the vaginal microbiota.

Microbiome 2021 05 28;9(1):124. Epub 2021 May 28.

IRDB, Department of Metabolism, Digestion and Reproduction - Surgery and Cancer, Hammersmith Campus, Imperial College London, W12 0NN, London, UK.

Background: Obesity and vaginal microbiome (VMB) dysbiosis are each risk factors for adverse reproductive and oncological health outcomes in women. Here, we investigated the relationship between obesity, vaginal bacterial composition, local inflammation and bariatric surgery.

Methods: Vaginal bacterial composition assessed by high-throughput sequencing of bacterial 16S rRNA genes and local cytokine levels measured using a multiplexed Magnetic Luminex Screening Assay were compared between 67 obese and 42 non-obese women. We further assessed temporal changes in the microbiota and cytokines in a subset of 27 women who underwent bariatric surgery.

Results: The bacterial component of the vaginal microbiota in obese women was characterised by a lower prevalence of a Lactobacillus-dominant VMB and higher prevalence of a high diversity (Lactobacillus spp., and Gardnerella- spp. depleted) VMB, compared with non-obese subjects (p<0.001). Obese women had higher relative abundance of Dialister species (p<0.001), Anaerococcus vaginalis (p=0.021), and Prevotella timonensis (p=0.020) and decreased relative abundance of Lactobacillus crispatus (p=0.014). Local vaginal IL-1β, IL-4, IL-6, IL-8, IFNγ, MIP-1α and TNFα levels were all higher among obese women, however, only IL-1β and IL-8 correlated with VMB species diversity. In a subset of obese women undergoing bariatric surgery, there were no significant overall differences in VMB following surgery; however, 75% of these women remained obese at 6 months. Prior to surgery, there was no relationship between body mass index (BMI) and VMB structure; however, post-surgery women with a Lactobacillus-dominant VMB had a significantly lower BMI than those with a high diversity VMB.

Conclusions: Obese women have a significantly different vaginal microbiota composition with increased levels of local inflammation compared to non-obese women. Bariatric surgery does not change the VMB; however, those with the greatest weight loss 6-month post-surgery are most likely to have a Lactobacillus-dominant VMB. Video abstract.
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http://dx.doi.org/10.1186/s40168-021-01011-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8164250PMC
May 2021

Symptomatic Diaphragmatic Hernia after Thoracofemoral Bypass.

Ann Vasc Surg 2021 Apr 5. Epub 2021 Apr 5.

Department of Surgery, Divisions of Vascular, VA Boston Healthcare System, West Roxbury, Massachusetts. Electronic address:

Despite its relative underutilization in the primary management of aortoiliac occlusive disease, thoracofemoral bypass is an attractive extra-anatomic surgical option in select patients. Thoracofemoral bypass classically entails passing a graft from the left chest into the retroperitoneal space through a small opening created in the diaphragm. While theoretically possible that this maneuver may predispose to a peri-graft diaphragmatic hernia, currently there are no cases of this complication reported in the literature, nor has its surgical repair been described. This case illustrates the rare complication of symptomatic diaphragmatic hernia following a thoracobifemoral bypass.
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http://dx.doi.org/10.1016/j.avsg.2021.01.106DOI Listing
April 2021

Development and Validation of a Measure of Birth-Related PTSD for Fathers and Birth Partners: The City Birth Trauma Scale (Partner Version).

Front Psychol 2021 3;12:596779. Epub 2021 Mar 3.

Perinatal Mental Health Service, West London NHS Trust, St Bernard's Hospital, London, United Kingdom.

Research suggests that some fathers and birth partners can experience post-traumatic stress disorder (PTSD) after witnessing a traumatic birth. Birth-related PTSD may impact on many aspects of fathers' and birth partners' life, including relationship breakdown, self-blame and reducing plans for future children. Despite the potential impact on birth partners' lives there is currently no measure of birth-related PTSD validated for use with birth partners. The current study therefore adapted the City Birth Trauma Scale for use with birth partners. The City Birth Trauma Scale (Partner version) is a 29-item questionnaire developed to measure birth-related PTSD according to DSM-5 criteria: stressor criteria (A), symptoms of re-experiencing (B), avoidance (C), negative cognitions and mood (D), and hyperarousal (E), as well as duration of symptoms (F), significant distress or impairment (G), and exclusion criteria or other causes (H). A sample of 301 fathers/birth partners was recruited online and completed measures of birth-related PTSD, bonding, and demographic details. Results showed the City Birth Trauma Scale (Partner version) had good reliability (α = 0.94) and psychometric and construct validity. The fathers/birth partners version has the same two-factor structure as the original scale: (1) general symptoms and (2) birth-related symptoms, which accounted for 51% of the variance. PTSD symptoms were associated with preterm birth and maternal and infant complications. Overall, the City Birth Trauma Scale (Partner version) provides a promising measure of PTSD following childbirth that can be used in research and clinical practice.
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http://dx.doi.org/10.3389/fpsyg.2021.596779DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7966709PMC
March 2021

-Depleted Vaginal Microbiota in Pregnant Women Living With HIV-1 Infection Are Associated With Increased Local Inflammation and Preterm Birth.

Front Cell Infect Microbiol 2020 11;10:596917. Epub 2021 Feb 11.

Department of Metabolism, Digestion, and Reproduction, March of Dimes Prematurity Research Centre, Division of the Institute of Reproductive and Developmental Biology, Faculty of Medicine, Imperial College London, London, United Kingdom.

Background: Pregnant women living with HIV-1 infection (PWLWH) have an elevated risk of preterm birth (PTB) of unknown aetiology, which remains after successful suppression of HIV. Women at high risk for HIV have a common bacterial profile which has been associated with poor birth outcomes. We set out to explore factors associated with gestational age at delivery of PWLWH in a UK population.

Methods: Prospective study of PWLWH (n = 53) in whom the vaginal microbiota and cervicovaginal cytokine were assessed using metataxonomics and multiplexed immunoassays, respectively. Cross-sectional characterisation of vaginal microbiota in PWLWH were compared with 22 HIV uninfected pregnant women (HUPW) at a similar second trimester timepoint. Within PWLWH the relationships between bacterial composition, inflammatory response, and gestational age at delivery were explored.

Findings: There was a high rate of PTB among PWLWH (12%). In the second trimester the vaginal microbiota was more diverse in PWLWH than in HUPW (Inverse Simpson Index, p = 0.0004 and Species Observed, p = 0.009). PWLWH had a lower prevalence of dominant vaginal microbiota group (VMB I, 15 vs 54%) than HUPW and higher prevalence of dominant (VMB III, 36 vs 9% and VMB IIIB, 15 vs 5%) and mixed anaerobes (VMB IV, 21 vs 0%). Across the second and third trimesters in PWLWH, VMB III/IIIB and IV were associated with PTB and with increased local inflammation [cervicovaginal fluid (CVF) cytokine concentrations in upper quartile]. High bacterial diversity and anaerobic bacterial abundance were also associated with CVF pro-inflammatory cytokines, most notably IL-1β.

Interpretation: There is an association between local inflammation, vaginal dysbiosis and PTB in PWLWH. Understanding the potential of antiretroviral therapies to influence this cascade will be important to improve birth outcomes in this population.
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http://dx.doi.org/10.3389/fcimb.2020.596917DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7905210PMC
June 2021

Using next-generation sequencing to develop a Shigella species threshold and profile faecal samples from suspected diarrhoea cases.

Authors:
Ann Smith

Folia Microbiol (Praha) 2021 Jun 10;66(3):399-410. Epub 2021 Feb 10.

Faculty of Health and Applied Sciences, University of the West of England, Bristol, UK.

Globally, it is estimated that there are 2 billion cases of diarrhoeal disease each year, with 525,000 children under the age of 5 years, dying from diarrhoea. This also affects 1 in 5 people in the UK each year. Rapid diagnosis, appropriate treatment and infection control measures are, therefore, particularly important. Currently, Public Health Wales and England Microbiology Division test for five key bacterial gastrointestinal pathogens, i.e. Escherichia coli O157 (VTEC), Shigella dysenteriae, Salmonella spp., Campylobacter spp. and Clostridioides difficile. There is, however, a poor success rate with identification of these pathogens, leaving the patient at risk from untreated infections. This study has developed effective and reliable tools with a high positive outcome for diagnosis of diarrhoeal infection. The study blindly analysed 592 samples, with the most abundant species being Shigella sonnei at 15%, and the top genus Bacteroides at 26%. Campylobacter spp. had an abundance of 4%, Clostridium difficile 3%, and Salmonella spp. 0.2%. There were also significant differences in abundance at genus level, between the Flemish Gut project and diarrhoea samples, with respect to Shigella (0.2%) and Campylobacter (0.1%). The project introduced a novel Shigella spp. (Escherichia) threshold of 5.32% to determine (Escherichia) a healthy or unhealthy community. A DMBiome model was developed to integrate the 5.32% threshold of Shigella spp., the Public Health laboratory tested pathogens, and two emerging enteropathogens. The overall positive outcome was that 89% of all samples were diagnosed with diarrhoea infections, leaving 11% unknown.
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http://dx.doi.org/10.1007/s12223-020-00846-wDOI Listing
June 2021

Grant application outcomes for biomedical researchers who participated in the National Research Mentoring Network's Grant Writing Coaching Programs.

PLoS One 2020 9;15(11):e0241851. Epub 2020 Nov 9.

Department of Family and Preventive Medicine, University of Utah School of Medicine, Salt Lake City, Utah, United States of America.

Background: A diverse research workforce is essential for catalyzing biomedical advancements, but this workforce goal is hindered by persistent sex and racial/ethnic disparities among investigators receiving research grants from the National Institutes of Health (NIH). In response, the NIH-funded National Research Mentoring Network implemented a Grant Writing Coaching Program (GCP) to provide diverse cohorts of early-career investigators across the United States with intensive coaching throughout the proposal development process. We evaluated the GCP's national reach and short-term impact on participants' proposal submissions and funding outcomes.

Methods: The GCP was delivered as six similar but distinct models. All models began with an in-person group session, followed by a series of coaching sessions over 4 to 12 months. Participants were surveyed at 6-, 12- and 18-months after program completion to assess proposal outcomes (submissions, awards). Self-reported data were verified and supplemented by searches of public repositories of awarded grants when available. Submission and award rates were derived from counts of participants who submitted or were awarded at least one grant proposal in a category (NIH, other federal, non-federal).

Results: From June 2015 through March 2019, 545 investigators (67% female, 61% under-represented racial/ethnic minority, URM) from 187 different institutions participated in the GCP. Among them, 324 (59% of participants) submitted at least one grant application and 134 (41% of submitters) received funding. A total of 164 grants were awarded, the majority being from the NIH (93, 56%). Of the 74 R01 (or similar) NIH research proposals submitted by GCP participants, 16 have been funded thus far (56% to URM, 75% to women). This 22% award rate exceeded the 2016-2018 NIH success rates for new R01s.

Conclusion: Inter- and intra-institutional grant writing coaching groups are a feasible and effective approach to supporting the grant acquisition efforts of early-career biomedical investigators, including women and those from URM groups.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0241851PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7652313PMC
January 2021

Heme-Induced Oxidation of Cysteine Groups of Myofilament Proteins Leads to Contractile Dysfunction of Permeabilized Human Skeletal Muscle Fibres.

Int J Mol Sci 2020 Oct 31;21(21). Epub 2020 Oct 31.

HAS-UD Vascular Biology and Myocardial Pathophysiology Research Group, Hungarian Academy of Sciences, H-4032 Debrecen, Hungary.

Heme released from red blood cells targets a number of cell components including the cytoskeleton. The purpose of the present study was to determine the impact of free heme (20-300 µM) on human skeletal muscle fibres made available during orthopedic surgery. Isometric force production and oxidative protein modifications were monitored in permeabilized skeletal muscle fibre segments. A single heme exposure (20 µM) to muscle fibres decreased Ca-activated maximal (active) force (F) by about 50% and evoked an approximately 3-fold increase in Ca-independent (passive) force (F). Oxidation of sulfhydryl (SH) groups was detected in structural proteins (e.g., nebulin, α-actinin, meromyosin 2) and in contractile proteins (e.g., myosin heavy chain and myosin-binding protein C) as well as in titin in the presence of 300 µM heme. This SH oxidation was not reversed by dithiothreitol (50 mM). Sulfenic acid (SOH) formation was also detected in the structural proteins (nebulin, α-actinin, meromyosin). Heme effects on SH oxidation and SOH formation were prevented by hemopexin (Hpx) and α1-microglobulin (A1M). These data suggest that free heme has a significant impact on human skeletal muscle fibres, whereby oxidative alterations in structural and contractile proteins limit contractile function. This may explain and or contribute to the weakness and increase of skeletal muscle stiffness in chronic heart failure, rhabdomyolysis, and other hemolytic diseases. Therefore, therapeutic use of Hpx and A1M supplementation might be effective in preventing heme-induced skeletal muscle alterations.
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http://dx.doi.org/10.3390/ijms21218172DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7663642PMC
October 2020

Early conscious prone positioning in patients with COVID-19 receiving continuous positive airway pressure: a retrospective analysis.

BMJ Open Respir Res 2020 09;7(1)

Department of Respiratory Medicine, Bristol Royal Infirmary, Bristol, UK

The global pandemic of COVID-19 has challenged the management of hypoxaemic respiratory failure and strained intensive care unit resources. While prone positioning (PP) is an established therapy in mechanically ventilated patients with acute respiratory distress syndrome (ARDS), its role in conscious patients is less well defined. We retrospectively reviewed our experience of implementing early PP in a cohort of 24 patients with acute hypoxaemic respiratory failure due to COVID-19 who required support with continuous positive airway pressure (CPAP). The use of PP alongside CPAP significantly increased both the ROX index and arterial oxygen pressure:fractional inspired oxygen (PaO:FiO) ratio from baseline values (ROX index: 7.0±2.5 baseline vs 11.4±3.7 CPAP+PP, p<0.0001; PaO:FiO ratio: 143±73 mm Hg baseline vs 252±87 mm Hg CPAP+PP, p<0.01), and the changes to both the ROX index and PaO:FiO ratio remained significant 1 hour after cessation of proning. The mean duration of PP in the first 24 hours was 8±5 hours. Few complications were observed and PP was continued for a mean of 10±5 days. From our experience in a dedicated COVID-19 respiratory high care unit, PP alongside CPAP therapy was feasible, tolerated, safe and improved oxygenation. The use of conscious PP in ARDS warrants further investigation in randomised controlled trials.
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http://dx.doi.org/10.1136/bmjresp-2020-000711DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7476421PMC
September 2020

Development and Validation of WeCares, a Survey Instrument to Assess Hospitalized Patients' and Family Members' "Willingness to Engage in Your Care and Safety".

Jt Comm J Qual Patient Saf 2020 10 26;46(10):565-572. Epub 2020 Jul 26.

Background: Patient engagement is recognized as a method to improve care quality and safety. A research team developed WeCares (Willingness to Engage in Your Care and Safety), a survey instrument assessing patients' and families' engagement in the safety of their care during their hospital stay. The objective of this study is to establish the preliminary construct validity and internal consistency of WeCares.

Methods: WeCares was distributed to patients and families. With the survey responses, exploratory factor analysis (EFA) was performed to identify the factorial structure of WeCares. The internal consistency was assessed using Cronbach's alpha. Descriptive and comparative analysis was also performed to summarize patients' and families' responses.

Results: A total of 247 patients and families responded to the WeCare survey, of which 224 were used for EFA. EFA resulted in a 13-item, four-factor structure, including (1) comfortable sharing concerns, (2) responsibility for preventing errors, (3) perception of care team members' attitude, and (4) patients'/families' role in preventing errors. The Cronbach alphas were 0.716-0.866, indicating acceptable internal consistency. Overall, patients and families were comfortable sharing concerns with clinicians but preferred to remain anonymous. They believed that the care team members hold most responsibility for error prevention, however, and agreed on their ability to help prevent errors.

Conclusion: WeCares was developed to assess patients' and families' willingness to engage. WeCares can also be used to facilitate conversation about safety concerns and shared responsibility. The study team believes this would lead to patient activation in guarding their own care and ultimately improve patient outcomes and safety.
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http://dx.doi.org/10.1016/j.jcjq.2020.07.002DOI Listing
October 2020

De Novo KAT5 Variants Cause a Syndrome with Recognizable Facial Dysmorphisms, Cerebellar Atrophy, Sleep Disturbance, and Epilepsy.

Am J Hum Genet 2020 09 20;107(3):564-574. Epub 2020 Aug 20.

Sainte-Justine Hospital Research Center, University of Montreal, Montreal, QC H3T 1C5, Canada. Electronic address:

KAT5 encodes an essential lysine acetyltransferase, previously called TIP60, which is involved in regulating gene expression, DNA repair, chromatin remodeling, apoptosis, and cell proliferation; but it remains unclear whether variants in this gene cause a genetic disease. Here, we study three individuals with heterozygous de novo missense variants in KAT5 that affect normally invariant residues, with one at the chromodomain (p.Arg53His) and two at or near the acetyl-CoA binding site (p.Cys369Ser and p.Ser413Ala). All three individuals have cerebral malformations, seizures, global developmental delay or intellectual disability, and severe sleep disturbance. Progressive cerebellar atrophy was also noted. Histone acetylation assays with purified variant KAT5 demonstrated that the variants decrease or abolish the ability of the resulting NuA4/TIP60 multi-subunit complexes to acetylate the histone H4 tail in chromatin. Transcriptomic analysis in affected individual fibroblasts showed deregulation of multiple genes that control development. Moreover, there was also upregulated expression of PER1 (a key gene involved in circadian control) in agreement with sleep anomalies in all of the individuals. In conclusion, dominant missense KAT5 variants cause histone acetylation deficiency with transcriptional dysregulation of multiples genes, thereby leading to a neurodevelopmental syndrome with sleep disturbance, cerebellar atrophy, and facial dysmorphisms, and suggesting a recognizable syndrome.
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http://dx.doi.org/10.1016/j.ajhg.2020.08.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7477011PMC
September 2020

The vaginal microbiota associates with the regression of untreated cervical intraepithelial neoplasia 2 lesions.

Nat Commun 2020 04 24;11(1):1999. Epub 2020 Apr 24.

Institute for Reproductive and Developmental Biology, Imperial College, Hammersmith Hospital Campus, London, W12 0NN, UK.

Emerging evidence suggests associations between the vaginal microbiota (VMB) composition, human papillomavirus (HPV) infection, and cervical intraepithelial neoplasia (CIN); however, causal inference remains uncertain. Here, we use bacterial DNA sequencing from serially collected vaginal samples from a cohort of 87 adolescent and young women aged 16-26 years with histologically confirmed, untreated CIN2 lesions to determine whether VMB composition affects rates of regression over 24 months. We show that women with a Lactobacillus-dominant microbiome at baseline are more likely to have regressive disease at 12 months. Lactobacillus spp. depletion and presence of specific anaerobic taxa including Megasphaera, Prevotella timonensis and Gardnerella vaginalis are associated with CIN2 persistence and slower regression. These findings suggest that VMB composition may be a future useful biomarker in predicting disease outcome and tailoring surveillance, whilst it may offer rational targets for the development of new prevention and treatment strategies.
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http://dx.doi.org/10.1038/s41467-020-15856-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7181700PMC
April 2020

A Novel Tablet-Based Approach for Hearing Screening of the Pediatric Population, 516-Patient Study.

Laryngoscope 2020 09 29;130(9):2245-2251. Epub 2019 Oct 29.

ENT Department, Children's Hospital of the Chongqing Medical University, Chongqing, China.

Objective: Assess a tablet hearing game as a screening instrument for pediatric hearing loss.

Methods: All children age 3 to 13 presenting to the ENT clinic of a tertiary hospital clinic over a 3-month period were eligible for study. Five hundred sixteen were entered by completing the tablet screen with calibrated tablet/headphones. All had full standard audiometry or otoacoustic emission testing to assess hearing status. Tablet game data was analyzed to find the best correlation to the air conduction audiogram. The appropriate pass threshold of the tablet game was established and the statistical accuracy of the tablet game versus the air conduction audio was assessed.

Results: The overall rate of hearing loss was 29.7% (153 subjects). Conductive hearing loss predominated and was present in 128 children. The tablet game pure tone average from 500- 4000 Hz correlated best with the air conduction audiogram, and was most predictive of hearing loss. Setting the pass level at 20 dB for the tablet screen prioritized detection of hearing loss, yielding a sensitivity of 91% and corresponding specificity of 73.5% for ages 4 and older. Specificity progressively improved with increasing age and was over 90% for all ages 7 and older.

Conclusion: Tablet game audiometry as a screening tool performs well in a controlled setting. Based on these results, it can be considered as a reliable screening method for school-age children and to monitor resolution of otitis media.

Level Of Evidence: 4, case series Laryngoscope, 130:2245-2251, 2020.
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http://dx.doi.org/10.1002/lary.28329DOI Listing
September 2020

What Is Next in This "Age" of Heme-Driven Pathology and Protection by Hemopexin? An Update and Links with Iron.

Pharmaceuticals (Basel) 2019 Sep 24;12(4). Epub 2019 Sep 24.

Department of Biochemistry & Molecular Biology, School of Biological & Chemical Sciences, University of Missouri-Kansas City, MO 64110, USA.

This review provides a synopsis of the published literature over the past two years on the heme-binding protein hemopexin (HPX), with some background information on the biochemistry of the HPX system. One focus is on the mechanisms of heme-driven pathology in the context of heme and iron homeostasis in human health and disease. The heme-binding protein hemopexin is a multi-functional protectant against hemoglobin (Hb)-derived heme toxicity as well as mitigating heme-mediated effects on immune cells, endothelial cells, and stem cells that collectively contribute to driving inflammation, perturbing vascular hemostasis and blood-brain barrier function. Heme toxicity, which may lead to iron toxicity, is recognized increasingly in a wide range of conditions involving hemolysis and immune system activation and, in this review, we highlight some newly identified actions of heme and hemopexin especially in situations where normal processes fail to maintain heme and iron homeostasis. Finally, we present preliminary data showing that the cytokine IL-6 cross talks with activation of the c-Jun N-terminal kinase pathway in response to heme-hemopexin in models of hepatocytes. This indicates another level of complexity in the cell responses to elevated heme via the HPX system when the immune system is activated and/or in the presence of inflammation.
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http://dx.doi.org/10.3390/ph12040144DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6958331PMC
September 2019

'If I die, I die, I don't care about my health': Perspectives on self-care of people experiencing homelessness.

Health Soc Care Community 2020 01 6;28(1):160-172. Epub 2019 Sep 6.

College of Pharmacy, Qatar University, Doha, Qatar.

Self-care, which refers to what people do to prevent disease and maintain good health, can alleviate negative health consequences of people experiencing homelessness. The aim of the study was to apply a theoretically informed approach in exploring engagement of people experiencing homelessness in self-care and to identify factors that can be targeted in future health and social care interventions. Qualitative semi-structured interviews were conducted with 28 participants opportunistically recruited from a specialist homelessness healthcare centre of North East Scotland, the United Kingdom (UK). An interview schedule was developed based on the theoretical domains framework (TDF). Interviews were audio-recorded and transcribed verbatim. Six aspects of self-care were explored, including (a) self-awareness of physical and mental health, (b) health literacy, including health seeking behaviour, (c) healthy eating, (d) risk avoidance or mitigation, (v) physical activity and sleep and (e) maintaining personal hygiene. Thematic analysis was conducted by two independent researchers following the Framework Approach. Participants described low engagement in self-care. Most of the barriers to engagement in self-care by participants were related to 'environmental context and resources' domain of TDF. Participants often resorted to stealing or begging for food. Many perceived having low health literacy to interpret health-related information. Visits to churches and charities to get a shower or to obtain free meals were commonplace. Participants expressed pessimism that there was 'nothing' they could do to improve their health and described perceived barriers often too big for them to overcome. Alienation, lack of social support and the perception that they had done irreversible damage to their health prevented their involvement in self-care. The theme of 'social circle' held examples of both enabler and barriers in participants' uptake of risky behaviours. Health and social services should work with persons experiencing homelessness in designing and delivering targeted interventions that address contextual barriers, multi-morbidity, health literacy and self-efficacy.
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http://dx.doi.org/10.1111/hsc.12850DOI Listing
January 2020

Molecular community profiling of the bacterial microbiota associated with denture-related stomatitis.

Sci Rep 2019 07 15;9(1):10228. Epub 2019 Jul 15.

Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, UK.

Denture-associated stomatitis (DS) affects over two-thirds of denture-wearers. DS presents as erythema of the palatal mucosa in areas where denture-surface associated polymicrobial biofilms containing the fungus Candida albicans exist. The contribution of the oral bacterial microbiota toward the infection is unknown. Therefore, this study characterised the bacterial microbiota of sites within the oral cavity to identify potential associations with occurrence of DS. Denture-wearing patients were recruited (denture stomatitis (DS) n = 8; non-denture stomatitis (NoDS) n = 11) and the oral bacterial microbiota of the tongue, palate and denture-fitting surface was characterised using next-generation sequencing. Operational taxonomic units (OTUs) were identified to bacterial genera and species, and presence/absence and relative abundances were examined. A significant (P = 0.007) decrease in the number of OTUs and thus, diversity of the microbiota was observed in tongue samples of DS patients (vs non-DS). The microbiota of denture-fitting surfaces and palatal mucosae were similar. Large differences in the abundance of bacterial genera and species were observed at each sample site, and unique presence/absence of bacteria was noted. Presence/absence and relative abundance of specific bacteria associated with DS warrants further in vitro and in vivo evaluation, particularly as our previous work has shown C. albicans virulence factor modulation by oral bacteria.
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http://dx.doi.org/10.1038/s41598-019-46494-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6629705PMC
July 2019

Psychometric Evaluation of a Tool for Assessment of Clinical Development in Newly Licensed Registered Nurses.

J Nurs Meas 2019 04;27(1):E1-E16

Richardson Independent School District, Richardson, TX.

Background And Purpose: For effective evaluation of clinical development, established psychometric properties of reliability and validity are essential. The Clinical Development Assessment (CDA) tool was developed within a 12-month pediatric nurse residency program. Benner's novice-to-expert model framed the development of the CDA.

Methods: Data from 129 nurse residents and their preceptors were used to evaluate internal consistency reliability and face, content, and construct validity. Nine elements were assigned a six-point Likert scale scored as (a) unsafe, (b) novice, (c) advanced beginner, (d) competent, (e) proficient, and (f) expert.

Results: Moderately strong reliability was found. Using exploratory factor analysis, a single factor accounted for 68% of the variance in clinical development. Face and content validity were confirmed.

Conclusions: This study identified a brief, valid, and reliable tool to evaluate clinical development in newly licensed registered nurses.
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http://dx.doi.org/10.1891/1061-3749.27.1.E1DOI Listing
April 2019

Enhanced Microbial Bile Acid Deconjugation and Impaired Ileal Uptake in Pregnancy Repress Intestinal Regulation of Bile Acid Synthesis.

Hepatology 2019 07 21;70(1):276-293. Epub 2019 May 21.

Division of Women and Children's Health, King's College London, London, United Kingdom.

Pregnancy is associated with progressive hypercholanemia, hypercholesterolemia, and hypertriglyceridemia, which can result in metabolic disease in susceptible women. Gut signals modify hepatic homeostatic pathways, linking intestinal content to metabolic activity. We sought to identify whether enteric endocrine signals contribute to raised serum bile acids observed in human and murine pregnancies, by measuring fibroblast growth factor (FGF) 19/15 protein and mRNA levels, and 7α-hydroxy-4-cholesten-3-one. Terminal ileal farnesoid X receptor (FXR)-mediated gene expression and apical sodium bile acid transporter (ASBT) protein concentration were measured by qPCR and western blotting. Shotgun whole-genome sequencing and ultra-performance liquid chromatography tandem mass spectrometry were used to determine the cecal microbiome and metabonome. Targeted and untargeted pathway analyses were performed to predict the systemic effects of the altered metagenome and metabolite profiles. Dietary CA supplementation was used to determine whether the observed alterations could be overcome by intestinal bile acids functioning as FXR agonists. Human and murine pregnancy were associated with reduced intestinal FXR signaling, with lower FGF19/15 and resultant increased hepatic bile acid synthesis. Terminal ileal ASBT protein was reduced in murine pregnancy. Cecal bile acid conjugation was reduced in pregnancy because of elevated bile salt hydrolase-producing Bacteroidetes. CA supplementation induced intestinal FXR signaling, which was not abrogated by pregnancy, with strikingly similar changes to the microbiota and metabonome as identified in pregnancy. Conclusion: The altered intestinal microbiota of pregnancy enhance bile acid deconjugation, reducing ileal bile acid uptake and lowering FXR induction in enterocytes. This exacerbates the effects mediated by reduced bile acid uptake transporters in pregnancy. Thus, in pregnant women and mice, there is reduced FGF19/15-mediated hepatic repression of hepatic bile acid synthesis, resulting in hypercholanemia.
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http://dx.doi.org/10.1002/hep.30661DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6619257PMC
July 2019

Twenty-four-hour motor activity and body temperature patterns suggest altered central circadian timekeeping in Smith-Magenis syndrome, a neurodevelopmental disorder.

Am J Med Genet A 2019 02;179(2):224-236

Division of Intramural Research at the National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland.

Smith-Magenis syndrome (SMS) is a contiguous gene syndrome linked to interstitial microdeletion, or mutation of RAI1, within chromosome 17p11.2. Key behavioral features of SMS include intellectual disability, sleep-disturbances, maladaptive, aggressive and self-injurious behaviors, hyperactivity, and sudden changes in mood. A distinguishing feature of this syndrome is an inverted pattern of melatonin characterized by elevated daytime and low nighttime melatonin levels. As the central circadian clock controls the 24-hr rhythm of melatonin, we hypothesized that the clock itself may contribute to the disrupted pattern of melatonin and sleep. In this report, 24-hr patterns of body temperature, a surrogate marker of clock-timing, and continuous wrist activity were collected to examine the links between body temperature, sleep behavior, and the circadian clock. In addition, age-dependent changes in sleep behavior were explored. Actigraphy-estimated sleep time for SMS was 1 hr less than expected across all ages studied. The timing of the 24-hr body temperature (Tb-24) rhythm was phase advanced, but not inverted. Compared to sibling (SIB) controls, the SMS group had less total night sleep, lower sleep efficiency, earlier sleep onset, earlier final awake times, increased waking after sleep onset (WASO), and increased daytime nap duration. The timing of wake onset varied with age, providing evidence of ongoing developmental sleep changes from childhood through adolescence. Clarification of the circadian and developmental factors that contribute to the disrupted and variable sleep patterns in this syndrome will be helpful in identifying more effective individualized treatments.
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http://dx.doi.org/10.1002/ajmg.a.61003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6699156PMC
February 2019

Establishment of vaginal microbiota composition in early pregnancy and its association with subsequent preterm prelabor rupture of the fetal membranes.

Transl Res 2019 05 27;207:30-43. Epub 2018 Dec 27.

Imperial College Parturition Research Group, Division of the Institute of Reproductive and Developmental Biology, Imperial College London, London, UK; March of Dimes European Preterm Birth Research Centre, Imperial College London, London, UK. Electronic address:

Vaginal bacterial community composition influences pregnancy outcome. Preterm prelabor rupture of the fetal membranes (PPROM), which precedes 30% of all spontaneous preterm births, is associated with high vaginal bacterial diversity prior to rupture. The point at which vaginal bacterial diversity is established before PPROM is unknown. In this study, we use metataxonomics to longitudinally characterize the vaginal bacterial composition from as early as 6 weeks of gestation in women at high (n = 38) and low (n = 22) risk of preterm birth who subsequently experience PPROM and in women delivering at term without complications (n = 36). Reduced Lactobacillus spp. abundance and high diversity was observed prior to PPROM in 20% and 26% of women at low and high risk of preterm births respectively, but in only 3% of women who delivered at term. PPROM was associated with instability of bacterial community structure during pregnancy and a shift toward higher diversity predominately occurring during the second trimester. This was characterized by increased relative abundance of potentially pathogenic species including Prevotella, Peptoniphilus, Streptococcus, and Dialister. This study identifies reduced Lactobacillus spp. abundance and increasing vaginal bacterial diversity as an early risk factor for PPROM and highlights the need for interventional studies designed to assess the impact of modifying vaginal bacterial composition for the prevention of preterm birth.
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http://dx.doi.org/10.1016/j.trsl.2018.12.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6489901PMC
May 2019

Early career biomedical grantsmanship self-efficacy: validation of an abbreviated self-assessment tool.

Ann N Y Acad Sci 2019 06 5;1445(1):17-26. Epub 2018 Dec 5.

Department of Family and Preventative Medicine, University of Utah, Salt Lake City, Utah.

A hallmark of success for early career biomedical researchers is the acquisition of research funding. There are marked disparities among principal investigators who submit grants and the likelihood of receiving national funding. The National Research Mentoring Network was funded by the National Institutes of Health to diversify the biomedical research workforce and included grantsmanship training for early career researchers. Self-efficacy in developing research grant applications is significantly improved over time with training and experience. We created a 19-item self-efficacy assessment inventory. Our aims were to confirm the internal consistency of a three-factor solution for grantsmanship confidence and to test the likelihood that self-efficacy influences grant proposal submission timing. We gathered data from 190 diverse biomedical trainees who completed NRMN grantsmanship training between August 2015 and June 2017. Findings revealed high internal consistency for items in each of three factors. There was a statistically significant association between self-efficacy mean scores and grant submission timing predicting that, for every one-point increase in the mean score, the odds of submitting a grant 6 months post-training increased by 69%. An abbreviated inventory of grantsmanship skills self-efficacy is a promising tool for monitoring changes over time in early career researchers and for promoting tailored grantsmanship interventions.
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http://dx.doi.org/10.1111/nyas.13995DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6551308PMC
June 2019

Heme Induces Endoplasmic Reticulum Stress (HIER Stress) in Human Aortic Smooth Muscle Cells.

Front Physiol 2018 20;9:1595. Epub 2018 Nov 20.

HAS-UD Vascular Biology and Myocardial Pathophysiology Research Group, Hungarian Academy of Sciences, Debrecen, Hungary.

Accumulation of damaged or misfolded proteins resulted from oxidative protein modification induces endoplasmic reticulum (ER) stress by activating the pathways of unfolded protein response. In pathologic hemolytic conditions, extracellular free hemoglobin is submitted to rapid oxidation causing heme release. Resident cells of atherosclerotic lesions, after intraplaque hemorrhage, are exposed to heme leading to oxidative injury. Therefore, we raised the question whether heme can also provoke ER stress. Smooth muscle cells are one of the key players of atherogenesis; thus, human aortic smooth muscle cells (HAoSMCs) were selected as a model cell to reveal the possible link between heme and ER stress. Using immunoblotting, quantitative polymerase chain reaction and immunocytochemistry, we quantitated the markers of ER stress. These were: phosphorylated eIF2α, Activating transcription factor-4 (ATF4), DNA-damage-inducible transcript 3 (also known as C/EBP homology protein, termed CHOP), X-box binding protein-1 (XBP1), Activating transcription factor-6 (ATF6), GRP78 (glucose-regulated protein, 78kDa) and heme responsive genes heme oxygenase-1 and ferritin. In addition, immunohistochemistry was performed on human carotid artery specimens from patients who had undergone carotid endarterectomy. We demonstrate that heme increases the phosphorylation of eiF2α in HAoSMCs and the expression of ATF4. Heme also enhances the splicing of XBP1 and the proteolytic cleavage of ATF6. Consequently, there is up-regulation of target genes increasing both mRNA and protein levels of CHOP and GRP78. However, TGFβ and collagen type I decreased. When the heme binding proteins, alpha-1-microglobulin (A1M) and hemopexin (Hpx) are present in cell media, the ER stress provoked by heme is inhibited. ER stress pathways are also retarded by the antioxidant N-acetyl cysteine (NAC) indicating that reactive oxygen species are involved in heme-induced ER stress. Consistent with these findings, elevated expression of the ER stress marker GRP78 and CHOP were observed in smooth muscle cells of complicated lesions with hemorrhage compared to either atheromas or healthy arteries. In conclusion, heme triggers ER stress in a time- and dose-dependent manner in HAoSMCs. A1M and Hpx as well as NAC effectively hamper heme-induced ER stress, supporting their use as a potential therapeutic approach to reverse such a deleterious effects of heme toxicity.
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http://dx.doi.org/10.3389/fphys.2018.01595DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6255930PMC
November 2018

Using a Virtual Community (the Health Equity Learning Collaboratory) to Support Early-Stage Investigators Pursuing Grant Funding.

Int J Environ Res Public Health 2018 10 30;15(11). Epub 2018 Oct 30.

Department of Physiology, Morehouse School of Medicine, Atlanta, GA 30310, USA.

Junior investigators often have limited access to networks of scientific experts and resources that facilitate competitive grant submissions. Since environments in which scientists are trained are critically important for long-term success, we built and tested a virtual environment for early-stage investigators (ESIs) working on grant proposals. The aim of this study was to evaluate the virtual community's influence on grant submission patterns among participants from underrepresented groups. As part of a grant writing coaching model, junior investigators were recruited into a professional development program designed to develop competitive grantsmanship skills. Designed by the Research Resources and Outreach Core (RROC) of the National Research Mentoring Network (NRMN), the Health Equity Learning Collaboratory (EQ-Collaboratory) provided a virtual community for social support, accountability, constructive feedback, and access to peer networks to help investigators overcome barriers to grant submission. This study assessed differences in outcomes for participants who completed the training within the EQ-Collaboratory compared to those who did not. The analyzed data revealed a statistically significant difference in the average time to submission for participants enrolled in the EQ-Collaboratory. EQ-Collaboratory ESIs submitted proposals 148.6 days earlier, ( < 0.0001). The results suggest that a supportive virtual environment can help investigators more quickly overcome barriers to grant submission.
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http://dx.doi.org/10.3390/ijerph15112408DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6265982PMC
October 2018

Concept Inventory Development Reveals Common Student Misconceptions about Microbiology.

J Microbiol Biol Educ 2017 30;18(3). Epub 2017 Oct 30.

Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706.

Misconceptions, or alternative conceptions, are incorrect understandings that students have incorporated into their prior knowledge. The goal of this study was the identification of misconceptions in microbiology held by undergraduate students upon entry into an introductory, general microbiology course. This work was the first step in developing a microbiology concept inventory based on the American Society for Microbiology's Recommended Curriculum Guidelines for Undergraduate Microbiology. Responses to true/false (T/F) questions accompanied by written explanations by undergraduate students at a diverse set of institutions were used to reveal misconceptions for fundamental microbiology concepts. These data were analyzed to identify the most difficult core concepts, misalignment between explanations and answer choices, and the most common misconceptions for each core concept. From across the core concepts, nineteen misconception themes found in at least 5% of the coded answers for a given question were identified. The top five misconceptions, with coded responses ranging from 19% to 43% of the explanations, are described, along with suggested classroom interventions. Identification of student misconceptions in microbiology provides a foundation upon which to understand students' prior knowledge and to design appropriate tools for improving instruction in microbiology.
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http://dx.doi.org/10.1128/jmbe.v18i3.1319DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5976041PMC
October 2017

Development, Validation, and Application of the Microbiology Concept Inventory.

J Microbiol Biol Educ 2017 5;18(3). Epub 2017 Oct 5.

Sam Houston State University, Huntsville, TX 77340.

If we are to teach effectively, tools are needed to measure student learning. A widely used method for quickly measuring student understanding of core concepts in a discipline is the concept inventory (CI). Using the American Society for Microbiology Curriculum Guidelines (ASMCG) for microbiology, faculty from 11 academic institutions created and validated a new microbiology concept inventory (MCI). The MCI was developed in three phases. In phase one, learning outcomes and fundamental statements from the ASMCG were used to create T/F questions coupled with open responses. In phase two, the 743 responses to MCI 1.0 were examined to find the most common misconceptions, which were used to create distractors for multiple-choice questions. MCI 2.0 was then administered to 1,043 students. The responses of these students were used to create MCI 3.0, a 23-question CI that measures students' understanding of all 27 fundamental statements. MCI 3.0 was found to be reliable, with a Cronbach's alpha score of 0.705 and Ferguson's delta of 0.97. Test item analysis demonstrated good validity and discriminatory power as judged by item difficulty, item discrimination, and point-biserial correlation coefficient. Comparison of pre- and posttest scores showed that microbiology students at 10 institutions showed an increase in understanding of concepts after instruction, except for questions probing metabolism (average normalized learning gain was 0.15). The MCI will enable quantitative analysis of student learning gains in understanding microbiology, help to identify misconceptions, and point toward areas where efforts should be made to develop teaching approaches to overcome them.
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http://dx.doi.org/10.1128/jmbe.v18i3.1320DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5976036PMC
October 2017

Nitrate-responsive oral microbiome modulates nitric oxide homeostasis and blood pressure in humans.

Free Radic Biol Med 2018 08 25;124:21-30. Epub 2018 May 25.

College of Life and Environmental Sciences, University of Exeter, Exeter EX1 1TE, UK.

Imbalances in the oral microbial community have been associated with reduced cardiovascular and metabolic health. A possible mechanism linking the oral microbiota to health is the nitrate (NO)-nitrite (NO)-nitric oxide (NO) pathway, which relies on oral bacteria to reduce NO to NO. NO (generated from both NO and L-arginine) regulates vascular endothelial function and therefore blood pressure (BP). By sequencing bacterial 16S rRNA genes we examined the relationships between the oral microbiome and physiological indices of NO bioavailability and possible changes in these variables following 10 days of NO (12 mmol/d) and placebo supplementation in young (18-22 yrs) and old (70-79 yrs) normotensive humans (n = 18). NO supplementation altered the salivary microbiome compared to placebo by increasing the relative abundance of Proteobacteria (+225%) and decreasing the relative abundance of Bacteroidetes (-46%; P < 0.05). After NOsupplementation the relative abundances of Rothia (+127%) and Neisseria (+351%) were greater, and Prevotella (-60%) and Veillonella (-65%) were lower than in the placebo condition (all P < 0.05). NO supplementation increased plasma concentration of NO and reduced systemic blood pressure in old (70-79 yrs), but not young (18-22 yrs), participants. High abundances of Rothia and Neisseria and low abundances of Prevotella and Veillonella were correlated with greater increases in plasma [NO] in response to NO supplementation. The current findings indicate that the oral microbiome is malleable to change with increased dietary intake of inorganic NO, and that diet-induced changes in the oral microbial community are related to indices of NO homeostasis and vascular health in vivo.
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http://dx.doi.org/10.1016/j.freeradbiomed.2018.05.078DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6191927PMC
August 2018

Mixed-Methods Evaluation of Real-Time Safety Reporting by Hospitalized Patients and Their Care Partners: The MySafeCare Application.

J Patient Saf 2020 06;16(2):e75-e81

Healthcare Systems Engineering Institute, Northeastern University.

Objective: The aims of the study were to evaluate the amount and content of data patients and care partners reported using a real-time electronic safety tool compared with other reporting mechanisms and to understand their perspectives on safety concerns and reporting in the hospital.

Methods: This study used mixed methods including 20-month preimplementation and postimplementation trial evaluating MySafeCare, a web-based application, which allows hospitalized patients/care partners to report safety concerns in real time. The study compared MySafeCare submission rates for three hospital units (oncology acute care, vascular intermediate care, medical intensive care) with submissions rates of Patient Family Relations (PFR) Department, a hospital service to address patient/family concerns. The study used triangulation of quantitative data with thematic analysis of safety concern submissions and patient/care partner interviews to understand submission content and perspectives on safety reporting.

Results: Thirty-two MySafeCare submissions were received with an average rate of 1.7 submissions per 1000 patient-days and a range of 0.3 to 4.8 submissions per 1000 patient-days across all units, indicating notable variation between units. MySafeCare submission rates were significantly higher than PFR submission rates during the postintervention period on the vascular unit (4.3 [95% confidence interval = 2.8-6.5] versus 1.5 [95% confidence interval = 0.7-3.1], Poisson) (P = 0.01). Overall trends indicated a decrease in PFR submissions after MySafeCare implementation. Triangulated data indicated patients preferred to report anonymously and did not want concerns submitted directly to their care team.

Conclusions: MySafeCare evaluation confirmed the potential value of providing an electronic, anonymous reporting tool in the hospital to capture safety concerns in real time. Such applications should be tested further as part of patient safety programs.
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http://dx.doi.org/10.1097/PTS.0000000000000493DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6204117PMC
June 2020

Emissions of organic compounds from produced water ponds I: Characteristics and speciation.

Sci Total Environ 2018 Apr 29;619-620:896-905. Epub 2017 Nov 29.

Wyoming Department of Environmental Quality, 200 West 17th St., Cheyenne, WY, USA.

We measured fluxes of methane, a suite of non-methane hydrocarbons (C2-C11), light alcohols, and carbon dioxide from oil and gas produced water storage and disposal ponds in Utah (Uinta Basin) and Wyoming (Upper Green River Basin) United States during 2013-2016. In this paper, we discuss the characteristics of produced water composition and air-water fluxes, with a focus on flux chamber measurements. In companion papers, we will (1) report on inverse modeling methods used to estimate emissions from produced water ponds, including comparisons with flux chamber measurements, and (2) discuss the development of mass transfer coefficients to estimate emissions and place emissions from produced water ponds in the context of all regional oil and gas-related emissions. Alcohols (made up mostly of methanol) were the most abundant organic compound group in produced water (91% of total volatile organic concentration, with upper and lower 95% confidence levels of 89 and 93%) but accounted for only 34% (28 to 41%) of total organic compound fluxes from produced water ponds. Non-methane hydrocarbons, which are much less water-soluble than methanol and less abundant in produced water, accounted for the majority of emitted organics. C6-C9 alkanes and aromatics dominated hydrocarbon fluxes, perhaps because lighter hydrocarbons had already volatilized from produced water prior to its arrival in storage or disposal ponds, while heavier hydrocarbons are less water soluble and less volatile. Fluxes of formaldehyde and other carbonyls were low (1% (1 to 2%) of total organic compound flux). The speciation and magnitude of fluxes varied strongly across the facilities measured and with the amount of time water had been exposed to the atmosphere. The presence or absence of ice also impacted fluxes.
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http://dx.doi.org/10.1016/j.scitotenv.2017.11.161DOI Listing
April 2018

Emissions of organic compounds from produced water ponds III: Mass-transfer coefficients, composition-emission correlations, and contributions to regional emissions.

Sci Total Environ 2018 Jun 3;627:860-868. Epub 2018 Feb 3.

Wyoming Department of Environmental Quality, 200 West 17th St., Cheyenne, WY, USA.

A common method for treating the aqueous phase (produced water) brought to the surface along with oil and natural gas is to discharge it into surface impoundments, also known as produced water ponds. Here we analyze data on the concentration of organic compounds in the water and on the flux of the same compounds into the atmosphere. Flux data extending from about 5 × 10 to 10 mg m h are consistent with mass-transfer laws given by the WATER9 semi-empirical algorithm, although empirical data display a noise level of about one order of magnitude and predictions by WATER9 are biased high. The data suggest partitioning between hydrocarbons in aqueous solution and in suspension, especially at higher overall concentrations. Salinity of the produced water does not have a detectable effect on hydrocarbon fluxes. Recently impounded waters are stronger emitters of hydrocarbons, while emissions of older waters are dominated by CO. This aging effect can be explained by assuming, first, poor vertical mixing in the ponds, and second, gradual oxidation of hydrocarbons to CO. Our measurements account for about 25% of the produced water ponds in the Uinta Basin, Eastern Utah, and when extrapolated to all ponds in the basin, account for about 4% to 14% of all organic compound emissions by the oil and natural gas sector of the basin, depending on the emissions inventory, and about 13% and 58%, respectively, of emissions of aromatics and alcohols.
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http://dx.doi.org/10.1016/j.scitotenv.2018.01.242DOI Listing
June 2018
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