Danielle Wallace

Dr. Danielle Wallace


Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 March 2017 in Marine Drugs
Verified
Journal Article
Open access
PDF file
MFMelissa Friedman
Melissa Friedman
MFMercedes Fernandez
Mercedes Fernandez
LBLorraine Backer
Lorraine Backer
RDRobert W. Dickey
Robert W. Dickey
JBJeffrey Bernstein
Jeffrey Bernstein
LFLora Fleming
Lora Fleming
Ciguatera Fish Poisoning (CFP) is the most frequently reported seafood-toxin illness in the world. It causes substantial human health, social, and economic impacts. The illness produces a complex array of gastrointestinal, neurological and neuropsychological, and cardiovascular symptoms, which may last days, weeks, or months. This paper is a general review of CFP including the human health effects of exposure to ciguatoxins (CTXs), diagnosis, human pathophysiology of CFP, treatment, detection of CTXs in fish, epidemiology of the illness, global dimensions, prevention, future directions, and recommendations for clinicians and patients. It updates and expands upon the previous review of CFP published by Friedman et al. (2008) and addresses new insights and relevant emerging global themes such as climate and environmental change, international market issues, and socioeconomic impacts of CFP. It also provides a proposed universal case definition for CFP designed to account for the variability in symptom presentation across different geographic regions. Information that is important but unchanged since the previous review has been reiterated. This article is intended for a broad audience, including resource and fishery managers, commercial and recreational fishers, public health officials, medical professionals, and other interested parties.

23 August 2023 in SLEEP
Verified
Journal Article
Closed access
PDF file
DWDanielle Wallace
Danielle Wallace
DJDayna A Johnson
Dayna A Johnson
SRSusan Redline
Susan Redline
TSTamar Sofer
Tamar Sofer
JKJoe Kossowsky
Joe Kossowsky
Study Objectives: Rest-activity rhythms (RAR) may mark development, aging, and physical and mental health. Understanding how they differ between people may inform intervention and health promotion efforts. However, RAR characteristics across the lifespan have not been well-studied. Therefore, we investigated the association between RAR measures with demographic and lifestyle factors in a US nationally representative study. Methods: RAR metrics of interdaily stability (IS), intradaily variability (IV), relative amplitude (RA), and mean amplitude and timing of high (M10) and low (L5) activity were derived from 2011 to 2012 and 2013 to 2014 National Health and Nutrition Examination Survey (NHANES) actigraphy data. Population-weighted linear and logistic regression models were fit to examine the associations of age, gender, smoking, alcohol, season, body mass index (BMI), income-to-poverty ratio, and race/ethnicity with RAR. Significance was based on a false-discovery rate-corrected P-value of <0.05. Results: Among n = 12 526 NHANES participants (3–≥80 years), IS (higher = greater day-to-day regularity) and RA (higher = greater rhythm strength) generally decreased with age and were lower among males, whereas IV (higher = greater rhythm fragmentation) increased with age (p < 0.05). Dynamic changes in RAR trajectories were observed during childhood and adolescence. Income, BMI, smoking, and alcohol use were associated with RAR metrics, as well as season among children and teenagers (p < 0.05). RAR also differed by race/ethnicity (p < 0.05), with trajectories initially diverging in childhood and continuing into adulthood. Conclusions: RAR differed by demographic and health-related factors, representing possible windows for public health intervention and sleep health promotion. RAR differences by race/ethnicity begin in childhood, are evident in early adolescence, and persist throughout adulthood.

18 June 2018 in Systems Biology in Reproductive Medicine
Verified
Journal Article
Closed access
ASAlyse N. Steves
Alyse N. Steves
ATAdam Turry
Adam Turry
BGBrittany Gill
Brittany Gill
DWDanielle Wallace
Danielle Wallace
JBJoshua M. Bradner
Joshua M. Bradner
Charles EasleyCharles Easley
Charles Easley
Per- and polyfluoroalkyl substances (PFASs) represent a highly ubiquitous group of synthetic chemicals used in products ranging from water and oil repellents and lubricants to firefighting foam. These substances can enter and accumulate in multiple tissue matrices in up to 100% of people assessed. Though animal models strongly identify these compounds as male reproductive toxicants, with exposed rodents experiencing declines in sperm count, alterations in hormones, and DNA damage in spermatids, among other adverse outcomes, human studies report conflicting conclusions as to the reproductive toxicity of these chemicals. Using an innovative, human stem-cell-based model of spermatogenesis, we assessed the effects of the PFASs perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and a mixture of PFOS, PFOA, and PFNA for their impacts on human spermatogenesis in vitro under conditions relevant to the general and occupationally exposed populations. Here, we show that PFOS, PFOA, PFNA, and a mixture of PFOS, PFOA, and PFNA do not decrease in vitro germ cell viability, consistent with reports from human studies. These compounds do not affect mitochondrial membrane potential or increase reactive oxygen species generation, and they do not decrease cell viability of spermatogonia, primary spermatocytes, secondary spermatocytes, or spermatids in vitro under the conditions examined. However, exposure to PFOS, PFOA, and PFNA reduces expression of markers for spermatogonia and primary spermatocytes. While not having direct effects on germ cell viability, these effects suggest the potential for long-term impacts on male fertility through the exhaustion of the spermatogonial stem cell pool and abnormalities in primary spermatocytes. Abbreviations: CDC: Centers for Disease Control; DMSO: dimethyl sulfoxide; GHR: growth hormone receptor; hESCs: human embryonic stem cells; PFASs: per- and polyfluoroalkyl substances; PFCs: perfluorinated compounds; PFNA: perfluorononanoic acid; PFOS: perfluorooctanesulfonic acid; PFOA: perfluorooctanoic acid; PLZF: promyelocytic leukemia zinc finger; ROS: reactive oxygen species; HILI: RNA-mediated gene silencing 2; SSC: spermatogonial stem cell

16 June 2023 in Sleep Medicine Reviews
Verified
Journal Article
Closed access
DWDanielle Wallace
Danielle Wallace
JGJayden Pace Gallagher
Jayden Pace Gallagher
SPShenita R. Peterson
Shenita R. Peterson
SNSeyni Ndiaye-Gueye
Seyni Ndiaye-Gueye
KFKathleen Fox
Kathleen Fox
DJDayna A. Johnson
Dayna A. Johnson

26 April 2019 in PLOS ONE
Verified
Journal Article
Open access
PDF file
DWDanielle Wallace
Danielle Wallace
TETodd M Everson
Todd M Everson
MDMaya A Deyssenroth
Maya A Deyssenroth
ABAmber A Burt
Amber A Burt
KHKaren E Hermetz
Karen E Hermetz
CMCarmen J Marsit
Carmen J Marsit
Circadian disruption is a common environmental and occupational exposure with public health consequences, but not much is known about whether circadian disruption affects in utero development. We investigated whether maternal circadian disruption, using night shift work as a proxy, is associated with variations in DNA methylation patterns of placental tissue in an epigenome-wide association study (EWAS) of night shift work. Here, we compared cytosine-guanosine dinucleotide (CpG) specific methylation genome-wide of placental tissue (measured with the Illumina 450K array) from participants (n = 237) in the Rhode Island Child Health Study (RICHS) who did (n = 53) and did not (n = 184) report working the night shift, using robust linear modeling and adjusting for maternal age, pre-pregnancy smoking, infant sex, maternal adversity, and putative cell mixture. Statistical analyses were adjusted for multiple comparisons and results presented with Bonferroni or Benjamini and Hochberg (BH) adjustment for false discovery rate. Night shift work was associated with differential methylation in placental tissue, including CpG sites in the genes NAV1, SMPD1, TAPBP, CLEC16A, DIP2C, FAM172A, and PLEKHG6 (Bonferroni-adjusted p<0.05). CpG sites within NAV1, MXRA8, GABRG1, PRDM16, WNT5A, and FOXG1 exhibited the most hypomethylation, while CpG sites within TDO2, ADAMTSL3, DLX2, and SERPINA1 exhibited the most hypermethylation (BH q<0.10). Functional analysis indicated GO-terms associated with cell-cell adhesion and enriched GWAS results for psoriasis. Night shift work was associated with differential methylation of the placenta, which may have implications for fetal health and development. This is the first study to examine the epigenetic impacts of night shift exposure, as a proxy for circadian disruption, on placental methylation in humans, and, while results should be interpreted with caution, suggests circadian disruption may have epigenetic impacts.

1 May 2018 in iScience
Verified
Journal Article
Open access
ASAlyse N. Steves
Alyse N. Steves
JBJoshua M. Bradner
Joshua M. Bradner
KFKristen L. Fowler
Kristen L. Fowler
DWDanielle Wallace
Danielle Wallace
BGBrittany J. Gill
Brittany J. Gill
Charles EasleyCharles Easley
Charles Easley
Sperm counts have rapidly declined in Western males over the past four decades. This rapid decline remains largely unexplained, but exposure to environmental toxicants provides one potential explanation for this decline. Flame retardants are highly prevalent and persistent in the environment, but many have not been assessed for their effects on human spermatogenesis. Using a human stem cell-based model of spermatogenesis, we evaluated two major flame retardants, hexabromocyclododecane (HBCDD) and tetrabromobisphenol A (TBBPA), under acute conditions simulating occupational-level exposures. Here we show that HBCDD and TBBPA are human male reproductive toxicants in vitro. Although these toxicants do not specifically affect the survival of haploid spermatids, they affect spermatogonia and primary spermatocytes through mitochondrial membrane potential perturbation and reactive oxygen species generation, ultimately causing apoptosis. Taken together, these results show that HBCDD and TBBPA affect human spermatogenesis in vitro and potentially implicate this highly prevalent class of toxicants in the decline of Western males' sperm counts.