Family history of dementia and brain health in childhood and middle age: a prospective community-based study.

We aimed to determine the association of family history of dementia with structural brain measures and cognitive performance in childhood and mid-life adulthood. We studied 1,259 parents (mean age: 47.3 years, range 31.9-67.4) and 866 of their children (mean age [range] at brain MRI: 9.9 years [8.8-11.9], and for cognition: 13.5 years [12.6-15.8]) of the population-based Generation R Study. Parents filled in a questionnaire on family history, and both parents and children underwent cognitive assessment and neuroimaging. Of all participants, 109 parents (8.6%) reported a parental family history of dementia and 73 children (8.4%) had a grandparental history of dementia with mean age of dementia diagnosis in those affected 75 years (± 7.3). We observed no associations of dementia family history with cognitive ability in either parents or their children, except for worse Purdue pegboard in parents with a parental history of dementia, compared to those without (mean difference [95%CI]: -1.23 [-2.15; -0.31], test range: 21-52). In parents and children, neuroimaging measures did not differ significantly by family history. Results did not depend on age, sex, and APOE genotype. Family history of dementia was associated with worse manual dexterity in mid-life adulthood, but not with any other measures of cognitive ability or subclinical brain health in childhood and mid-life. These findings suggest that the association of family history with dementia risk is due chiefly to neurodegenerative rather than neurodevelopmental processes, and might first present with reduced motor skills.

Bladder inflation to reduce hemorrhage secondary to a pelvic fracture.

Bladder inflation may be a temporizing measure to tamponade pelvic bleeding in select trauma cases to bridge the patient to definitive interventions. Ultrasonographic confirmation of an intact bladder with an adjacent pelvic haematoma in a shocked adult with pelvic fracture is used for subject selection. An illustrative example of physiologic and interventional radiological control of pelvic bleeding following bladder inflation with sterile saline is presented.

First Constraints on the Epoch of Reionization Using the Non-Gaussianity of the Kinematic Sunyaev-Zel'dovich Effect from the South Pole Telescope and Herschel-SPIRE Observations.

We report results from an analysis aimed at detecting the trispectrum of the kinematic Sunyaev-Zel'dovich (kSZ) effect by combining data from the South Pole Telescope (SPT) and Herschel-SPIRE experiments over a 100 deg^{2} field. The SPT observations combine data from the previous and current surveys, namely SPTpol and SPT-3G, to achieve depths of 4.5, 3, and 16 µK-arcmin in bands centered at 95, 150, and 220 GHz. For SPIRE, we include data from the 600 and 857 GHz bands. We reconstruct the velocity-induced large-scale correlation of the small-scale kSZ signal with a quadratic estimator that uses two cosmic microwave background (CMB) temperature maps, constructed by optimally combining data from all the frequency bands. We reject the null hypothesis of a zero trispectrum at 10.3σ level. However, the measured trispectrum contains contributions from both the kSZ and other undesired components, such as CMB lensing and astrophysical foregrounds, with kSZ being sub-dominant. We use the agora simulations to estimate the expected signal from CMB lensing and astrophysical foregrounds. After accounting for the contributions from CMB lensing and foreground signals, we do not detect an excess kSZ-only trispectrum and use this nondetection to set constraints on reionization. By applying a prior based on observations of the Gunn-Peterson trough, we obtain an upper limit on the duration of reionization of Δz_{re,50}<4.5 (95% confidence level). We find these constraints are fairly robust to foregrounds assumptions. This trispectrum measurement is independent of, but consistent with, Planck's optical depth measurement. This result is the first constraint on the epoch of reionization using the non-Gaussian nature of the kSZ signal.

Joint self-supervised and supervised contrastive learning for multimodal MRI data: Towards predicting abnormal neurodevelopment.

The integration of different imaging modalities, such as structural, diffusion tensor, and functional magnetic resonance imaging, with deep learning models has yielded promising outcomes in discerning phenotypic characteristics and enhancing disease diagnosis. The development of such a technique hinges on the efficient fusion of heterogeneous multimodal features, which initially reside within distinct representation spaces. Naively fusing the multimodal features does not adequately capture the complementary information and could even produce redundancy. In this work, we present a novel joint self-supervised and supervised contrastive learning method to learn the robust latent feature representation from multimodal MRI data, allowing the projection of heterogeneous features into a shared common space, and thereby amalgamating both complementary and analogous information across various modalities and among similar subjects. We performed a comparative analysis between our proposed method and alternative deep multimodal learning approaches. Through extensive experiments on two independent datasets, the results demonstrated that our method is significantly superior to several other deep multimodal learning methods in predicting abnormal neurodevelopment. Our method has the capability to facilitate computer-aided diagnosis within clinical practice, harnessing the power of multimodal data. The source code of the proposed model is publicly accessible on GitHub: https://github.com/leonzyzy/Contrastive-Network.

Assessing the association between necrotizing enterocolitis and the type of initial central venous access in preterm infants.

AIM: Umbilical venous catheters (UVC) have been associated with an increased risk of necrotizing enterocolitis (NEC). We aimed to assess the relationship between the type of initial central venous access in preterm infants and NEC. METHODS: Using the Canadian Neonatal Network database, we identified preterm infants <30 weeks gestation born between 2014 and 2021 in one of 32 participating centres who had a peripherally inserted central catheter (PICC) as initial vascular access. These infants were matched in a 1:1 ratio based on gestational age, sex and birth weight to infants in two other groups: (i) those who initially had an UVC and (ii) those who had an UVC followed by a PICC. RESULTS: A total of 497 infants were included in this study: 165 in the PICC group, 164 in the UVC group and 165 in the UVC + PICC group. There was no association between the type of initial central venous access and NEC. CONCLUSION: Although this retrospective study did not find an association between the type of initial central venous access and NEC, larger prospective studies are required to evaluate this association.

The intergroup dynamics of political cynicism: how perceived discrimination, outsiderness, and social capital relate to political cynicism among Moroccan and Turkish Belgians.

Introduction: This study examines how intergroup dynamics shape political cynicism among Belgians of Turkish and Moroccan descent. Concretely, we examine whether perceptions of discrimination, feelings of ethnic outsiderness and social capital (in terms of associational membership) can explain minorities' belief that political elites are selfish, incompetent, and immoral. Methods: We analyse data from the Belgian Ethnic Minorities Election Study 2014. Results: Arguing that political cynicism includes blame attribution towards the political establishment, we distinguish between perceived group discrimination by the government, on the labor market, and in everyday life. As expected, political cynicism is closely related to perceptions of government discrimination, with no observed correlation with discrimination in the other domains. Next, we show that perceived ethnic outsiderness is also strongly related to increased feelings of political cynicism, further reinforcing the argument that cynics are concerned with their ethnic group's excluded status and position in society. Finally, associational membership is only related to lower political cynicism when it is generated exclusively within ethnic boundaries; there was no relationship with cross-ethnic social capital. Discussion: Our findings show that intergroup indicators are highly relevant for understanding minorities' political cynicism, but that the intergroup dynamics operate in complex and nuanced ways.

A Large Percentage of Excision Specimens Show Residual Basal Cell Carcinoma: A Retrospective Chart Review.

BACKGROUND: Treatment of basal cell carcinoma (BCC) is recommended. However, patients often note that the biopsy site appears resolved and inquire about the need for additional treatment. OBJECTIVE: This study aims to determine the rate of residual BCC on excision specimens after initial shave biopsy to aid in decision-making on the necessity of further treatment. METHODS AND MATERIALS: A retrospective chart review was conducted that reviewed excision specimen pathology reports of previously biopsy-proven basal cell carcinomas for the presence of residual tumor between 2012 and 2022 at a single institution. RESULTS: Two thousand one hundred seventeen cases met inclusion criteria. Overall, 39.4% of patients had residual BCC after an initial shave biopsy. Using an odds ratio and 95% confidence interval, a significant relationship was found between larger lesions, longer time between biopsy and excision, and lesions on high-risk body sites with increased odds of residual BCC. A significant relationship was found between negative or not specified margins on shave biopsy with decreased odds of residual BCC. CONCLUSION: The results show that a large percentage of patients have residual BCC following initial biopsies. These results should be included in physician-patient discussions about treatment options for BCC.

Oral microbial diversity in 18th century African individuals from South Carolina.

As part of the Anson Street African Burial Ground Project, we characterized the oral microbiomes of twelve 18th century African-descended individuals (Ancestors) from Charleston, South Carolina, USA, to study their oral health and diet. We found that their oral microbiome composition resembled that of other historic (18th-19th century) dental calculus samples but differed from that of modern samples, and was not influenced by indicators of oral health and wear observed in the dentition. Phylogenetic analysis of the oral bacteria, Tannerella forsythia and Pseudoramibacter alactolyticus, revealed varied patterns of lineage diversity and replacement in the Americas, with the Ancestors carrying strains similar to historic period Europeans and Africans. Functional profiling of metabolic pathways suggested that the Ancestors consumed a diet low in animal protein. Overall, our study reveals important insights into the oral microbial histories of African-descended individuals, particularly oral health and diet in colonial North American enslavement contexts.

The association between maternal immune activation and brain structure and function in human offspring: a systematic review.

Maternal immune activation (MIA) during pregnancy, as a result of infectious or inflammatory stimuli, has gained increasing attention for its potential role in adverse child neurodevelopment, with studies focusing on associations in children born preterm. This systematic review summarizes research on the link between several types of prenatal MIA and subsequent child structural and/or functional brain development outcomes. We identified 111 neuroimaging studies in five MIA areas: inflammatory biomarkers (n = 13), chorioamnionitis (n = 18), other types of infections (n = 18), human immunodeficiency virus (HIV) (n = 42), and Zika virus (n = 20). Overall, there was large heterogeneity in the type of MIA exposure examined and in study methodology. Most studies had a prospective single cohort design and mainly focused on potential effects on the brain up to one year after birth. The median sample size was 53 participants. Severe infections, i.e., HIV and Zika virus, were associated with various types of cerebral lesions (e.g., microcephaly, atrophy, or periventricular leukomalacia) that were consistently identified across studies. For less severe infections and chronic inflammation, findings were generally inconsistent and mostly included deviations in white matter structure/function. Current findings have been mainly observed in the infants' brain, presenting an opportunity for future studies to investigate whether these associations persist throughout development. Additionally, the inconsistent findings, encompassing both regions of interest and null results, call into question whether prenatal exposure to less severe infections and chronic inflammation exerts a small effect or no effect on child brain development.

Tyrp1 is the mendelian determinant of the Axolotl (Ambystoma mexicanum) copper mutant.

Several dozen Mendelian mutants have been discovered in axolotl (Ambystoma mexicanum) populations, including several that affect pigmentation. Four recessive mutants have been described in the scientific literature and genes for three of these have been identified. Here we describe and genetically dissect copper, a mutant with an albino-like phenotype known only from the pet trade. We performed a cross segregating copper and wildtype color phenotypes and used bulked segregant RNA-Seq to identify a region on chromosome 6 that was enriched for single-nucleotide polymorphisms (SNPs) between the color phenotypes. This region included Tyrosinase-like Protein 1 (Tyrp1), a melanin synthesis protein that when mutated, is associated with lighter than black melanin coloration in animal models and oculocutaneous albinism in humans. Inspection of RNA-Seq reads identified a single nucleotide deletion that is predicted to change the coding frame, introduce a premature stop codon in exon 6 and yield a truncated Tyrp1 protein in copper individuals. Using CRISPR-Cas9 editing, we show that wildtype Tyrp1 crispants exhibit copper pigmentation, thus confirming Tyrp1 as the copper locus. Our results suggest that commercial and hobbyist axolotl populations may harbor useful mutants for biological research.

Structural and spectroscopic characterization of the peridinin-chlorophyll a-protein (PCP) complex from Heterocapsa pygmaea (HPPCP).

Light harvesting proteins are optimized to efficiently collect and transfer light energy for photosynthesis. In eukaryotic dinoflagellates these complexes utilize chlorophylls and a special carotenoid, peridinin, and arrange them for efficient excitation energy transfer. At the same time, the carotenoids protect the system by quenching harmful chlorophyll triplet states. Here we use advanced spectroscopic techniques and X-ray structure analysis to investigate excitation energy transfer processes in the major soluble antenna, the peridinin chlorophyll a protein (PCP) from the free living dinoflagellate Heterocapsa pygmaea. We determined the 3D-structure of this complex at high resolution (1.2 Å). For better comparison, we improved the reference structure of this protein from Amphidinium carterae to a resolution of 1.15 Å. We then used fs and ns time-resolved absorption spectroscopy to study the mechanisms of light harvesting, but also of the photoprotective quenching of the chlorophyll triplet state. The photoprotection site was further characterized by Electron Spin Echo Envelope Modulation (ESEEM) spectroscopy to yield information on water molecules involved in triplet-triplet energy transfer. Similar to other PCP complexes, excitation energy transfer from peridinin to chlorophyll is found to be very efficient, with transfer times in the range of 1.6-2.1 ps. One of the four carotenoids, the peridinin 614, is well positioned to quench the chlorophyll triplet state with high efficiency and transfer times in the range of tens of picoseconds. Our structural and dynamic data further support, that the intrinsic water molecule coordinating the chlorophyll Mg ion plays an essential role in photoprotection.

Risk factors for cardiometabolic health in Ghana: Cardiometabolic Risks Study Protocol-APTI Project.

Introduction: Cardiometabolic diseases are rapidly becoming primary causes of death in developing countries, including Ghana. However, risk factors for these diseases, including obesity phenotype, and availability of cost-effective diagnostic criteria are poorly documented in an African-ancestry populations in their native locations. The extent to which the environment, occupation, geography, stress, and sleep habits contribute to the development of Cardiometabolic disorders should be examined. Purpose: The overall goal of this study is to determine the prevalence of undiagnosed diabetes, prediabetes, and associated cardiovascular risks using a multi-sampled oral glucose tolerance test. The study will also investigate the phenotype and ocular characteristics of diabetes and prediabetes subgroups, as well as determine if lifestyle changes over a one-year period will impact the progression of diabetes and prediabetes. Methods and analysis: The study employs a community-based quasi-experimental design, making use of pre- and post-intervention data, as well as a questionnaire survey of 1200 individuals residing in the Cape Coast metropolis to ascertain the prevalence and risk factors for undiagnosed diabetes and prediabetes. Physical activity, dietary habits, stress levels, sleep patterns, body image perception, and demographic characteristics will be assessed. Glucose dysregulation will be detected using oral glucose tolerance test, fasting plasma glucose, and glycated hemoglobin. Liver and kidney function will also be assessed. Diabetes and prediabetes will be classified using the American Diabetes Association criteria. Descriptive statistics, including percentages, will be used to determine the prevalence of undiagnosed diabetes and cardiovascular risks. Inferential statistics, including ANOVA, t-tests, chi-square tests, ROC curves, logistic regression, and linear mixed model regression will be used to analyze the phenotypic variations in the population, ocular characteristics, glycemic levels, sensitivity levels of diagnostic tests, etiological cause of diabetes in the population, and effects of lifestyle modifications, respectively. Additionally, t-tests will be used to assess changes in glucose regulation biomarkers after lifestyle modifications. Ethics and dissemination: Ethics approval was granted by the Institutional Review Board of the University of Cape Coast, Ghana (UCCIRB/EXT/2022/27). The findings will be disseminated in community workshops, online learning platforms, academic conferences and submitted to peer-reviewed journals for publication.

Testing of rapid evaporative mass spectrometry for histological tissue classification and molecular diagnostics in a multi-site study.

BACKGROUND: While REIMS technology has successfully been demonstrated for the histological identification of ex-vivo breast tumor tissues, questions regarding the robustness of the approach and the possibility of tumor molecular diagnostics still remain unanswered. In the current study, we set out to determine whether it is possible to acquire cross-comparable REIMS datasets at multiple sites for the identification of breast tumors and subtypes. METHODS: A consortium of four sites with three of them having access to fresh surgical tissue samples performed tissue analysis using identical REIMS setups and protocols. Overall, 21 breast cancer specimens containing pathology-validated tumor and adipose tissues were analyzed and results were compared using uni- and multivariate statistics on normal, WT and PIK3CA mutant ductal carcinomas. RESULTS: Statistical analysis of data from standards showed significant differences between sites and individual users. However, the multivariate classification models created from breast cancer data elicited 97.1% and 98.6% correct classification for leave-one-site-out and leave-one-patient-out cross validation. Molecular subtypes represented by PIK3CA mutation gave consistent results across sites. CONCLUSIONS: The results clearly demonstrate the feasibility of creating and using global classification models for a REIMS-based margin assessment tool, supporting the clinical translatability of the approach.

Survival Analysis and Recurrence Patterns in 555 Patients with Colorectal Peritoneal Metastases Treated by Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy.

BACKGROUND: The presence at diagnosis, or development of, colorectal peritoneal metastases (CPM) is common in colorectal cancer. Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) show promising results in selected patients with CPM. The current study aimed to describe oncologic outcomes of patients with CPM, focusing on recurrence patterns and risk factors for adverse events. METHODS: We conducted a retrospective review of patients with CPM treated by CRS and HIPEC at a single institution between 2000 and 2021. RESULTS: A total of 555 patients were included, of whom 480 (86.5%) had complete cytoreduction, with a median age of 59 years and median Peritoneal Cancer Index (PCI) of 6. Following complete cytoreduction, 5-year overall survival (OS) and disease-free survival (DFS) were 51% and 31%, respectively. In multivariable Cox regression, PCI >6 (hazard ratio [HR] 2.25), pathological node positivity (pN+; HR 1.94), and perineural invasion (HR 1.85) were associated with decreased OS, while PCI >6, pN+, and previous systemic metastases resulted in reduced DFS. Overall, 284 (62%) patients developed recurrence, of whom 97 (34%) had local recurrence (LR), 100 (35%) had systemic recurrence (SR), and 87 (31%) had combined recurrence (5-year OS: 49.3%, 46%, and 37.4%, respectively). Mutated KRAS (mKRAS) was associated with lower 5-year OS (55.8%) and DFS (27.9%) compared with wild-type KRAS (wtKRAS; 70.7% and 37.6%, respectively). In multivariable analyses, mKRAS was related to decreased OS (HR 1.82), DFS (HR 1.55), and SR (OS 1.89), but not to LR. CONCLUSIONS: Complete cytoreduction results in good survival outcomes for patients with CPM. Burden of peritoneal disease and tumor biology are the main predictors of survival. Patients with mKRAS are a high-risk cohort, with increased probability of SR and reduced survival.

Mapping prenatal predictors and neurobehavioral outcomes of an epigenetic marker of neonatal inflammation - A longitudinal population-based study.

BACKGROUND: DNA methylation levels at specific sites can be used to proxy C-reactive protein (CRP) levels, providing a potentially more stable and accurate indicator of sustained inflammation and associated health risk. However, its use has been primarily limited to adults or preterm infants, and little is known about determinants for - or offspring outcomes of - elevated levels of this epigenetic proxy in cord blood. The aim of this study was to comprehensively map prenatal predictors and long-term neurobehavioral outcomes of neonatal inflammation, as assessed with an epigenetic proxy of inflammation in cord blood, in the general pediatric population. METHODS: Our study was embedded in the prospective population-based Generation R Study (n = 2,394). We created a methylation profile score of CRP (MPS-CRP) in cord blood as a marker of neonatal inflammation and validated it against serum CRP levels in mothers during pregnancy, as well as offspring at birth and in childhood. We then examined (i) which factors (previously associated with sustained inflammation) explain variability in MPS-CRP at birth, including a wide range of prenatal lifestyle and clinical conditions, pro-inflammatory exposures, as well as child genetic liability to elevated CRP levels; and (ii) whether MPS-CRP at birth associates with child neurobehavioral outcomes, including global structural MRI and DTI measures (child mean age 10 and 14 years) as well as psychiatric symptoms over time (Child Behavioral Checklist, at mean age 1.5, 3, 6, 10 and 14 years). RESULTS: MPS-CRP at birth was validated with serum CRP in cord blood (cut-off > 1 mg/L) (AUC = 0.72). Prenatal lifestyle pro-inflammatory factors explained a small part (i.e., < 5%) of the variance in the MPS-CRP at birth. No other prenatal predictor or the polygenic score of CRP in the child explained significant variance in the MPS-CRP at birth. The MPS-CRP at birth prospectively associated with a reduction in global fractional anisotropy over time on mainly a nominal threshold (ß = -0.014, SE = 0.007, p = 0.032), as well as showing nominal associations with structural differences (amygdala [(ß = 0.016, SE = 0.006, p = 0.010], cerebellum [(ß = -0.007, SE = 0.003, p = 0.036]). However, no associations with child psychiatric symptoms were observed. CONCLUSION: Prenatal exposure to lifestyle-related pro-inflammatory factors was the only prenatal predictor that accounted for some of the individual variability in MPS-CRP levels at birth. Further, while the MPS-CRP prospectively associated with white matter alterations over time, no associations were observed at the behavioral level. Thus, the relevance and potential utility of using epigenetic data as a marker of neonatal inflammation in the general population remain unclear. In the future, the use of epigenetic proxies for a wider range of immune markers may lend further insights into the relationship between neonatal inflammation and adverse neurodevelopment within the general pediatric population.

Three-Month Follow-Up of the Post-COVID Syndrome after Admission to a Specialised Post-COVID Centre-A Prospective Study Focusing on Mental Health with Patient Reported Outcome Measures (PROMs).

BACKGROUND AND OBJECTIVE: The impairments and duration of PASC (post-acute sequelae of COVID-19) symptoms in mental health have, to date, not been comprehensively examined. Our objective is to provide longitudinal data on the mental health of Post-COVID patients and to identify risk and protective factors associated with a severe or prolonged course. METHODS: The mental health of 265 Post-COVID patients of the outpatient Post-COVID centre of the University Hospital Erlangen was assessed 17.1 (T0) and 22.5 months after infection (T1). An online survey with validated questionnaires for Post-COVID symptoms (Post-COVID Syndrome Score), depression (Patient Health Questionnaire-9), somatic symptoms (Patient Health Questionnaire-15), anxiety (Generalized Anxiety Disorder-7), fatigue (Fatigue Severity Scale) and Post-Exertional Malaise (PEM) (DePaul Post-Exertional Malaise Screening) was conducted in the home environment. RESULTS: In total, 80% of patients experienced severe PASC at follow-up. Clinically relevant symptoms of depression, persistent somatic symptoms, anxiety and fatigue were reported by 55.8%, 72.5%, 18.9% and 89.4% of patients, respectively. Depressive, anxiety and somatic symptom severity decreased significantly over time; fatigue and PEM remained at an unchanged high level. The risk factor for higher depression scores was older age; prior psychiatric illness treated with psychotherapy was associated with more severe depressive, somatic, anxiety and PASC symptoms. PEM symptoms were significantly associated with longer duration between acute infection and initial presentation in the Post-COVID centre. CONCLUSIONS: Our findings align with previous research, claiming severe mental health symptoms in PASC syndrome, lasting for months after infection. In-depth assessment of risk and protective factors for the mental health implications of PASC is needed for the planning of health services and disease prevention.

Chem4Energy: a consortium of the Royal Society Africa Capacity-Building Initiative.

The Africa Capacity-Building Initiative is a Royal Society programme funded by the former UK Department for International Development to develop collaborative research between scientists in sub-Saharan Africa and the UK. Initially, four institutions were involved in the Chem4Energy consortium: Cardiff University in the UK and three African partners, the Kwame Nkrumah University of Science and Technology, Ghana, the University of Namibia and the University of Botswana, soon also including the Botswana International University of Science and Technology. The Chem4Energy research programme focused on 'New materials for a sustainable energy future: linking computation with experiment', aiming to deploy the synergy between state-of-the-art computational and experimental techniques to design and optimize new catalysts and semiconductor materials for renewable energy applications, based on materials that are abundant and readily available in African countries. The Chem4Energy consortium has achieved ambitious research goals, graduated seven PhD students and delivered a high-quality cross-disciplinary training programme in materials science and simulation techniques relevant to renewable energy applications. Since 2021, the extended consortium, including North-West University and the Centre for High-Performance Computing in South Africa, has remained active through an annual Chem4Energy conference series, with the sixth meeting taking place in Namibia in April 2025.

Developing an Agent-Based Model that Predicts Listeria spp. Transmission to Assess Listeria Control Strategies in Retail Stores.

Contamination of fresh produce with Listeria monocytogenes can occur throughout the supply chain, including at retail, where Listeria spp., including L. monocytogenes, may be introduced and spread via various routes. However, limited tools are available for retailers to assess practices that can enhance control of Listeria transmission to fresh produce. Therefore, we developed an agent-based model that can simulate Listeria transmission in retail produce sections to optimize environmental sampling programs and evaluate control strategies. A single retail store was used as a model environment, in which various routes of Listeria introduction into and transmission between environmental surfaces were modeled. Model prediction (i.e., Listeria prevalence) was validated using a published longitudinal study for all surfaces that were included in both the model and the validation data. Sensitivity analysis using the Partial Rank Correlation Coefficient showed that (i) initial Listeria concentration from incoming produce, (ii) transfer coefficient from produce to employee's hands, and (iii) transfer coefficient from consumer to produce were the top three parameters that were significantly (p < 0.0018) associated with the mean Listeria prevalence across all agents, suggesting that the accuracy of these parameters are important for prediction of overall Listeria prevalence at retail. Cluster analysis grouped agents with similar contamination patterns into six unique clusters; this information can be used to optimize the sampling plans for retail environments. Scenario analysis suggested that (i) more stringent supplier control as well as (ii) practices reducing Listeria transmission via consumer's hands may have the largest impact on reducing finished product contamination. Overall, we show that an agent-based model can serve as a foundational tool to help with decision-making on Listeria control strategies at retail.