Scholarly Works, Virginia Tech Carilion School of Medicine (VTCSOM)

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Research articles, presentations, and other scholarship

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Medial Femoral Condyle (MFC) Bone Flap
Capito, Anthony E. (2024-12-07)
Stablyx Hemiarthroplasty Implant Survivorship in Thumb Carpometacarpal Arthritis
Gray, Kelsey M.; Novikova, Camden; Peterman, Nick; McCarthy, Micheala; Apel, Peter; Capito, Anthony E. (2025-01-15)
Reinforcement learning processes as forecasters of depression remission
Bansal, Vansh; McCurry, Katherine L.; Lisinski, Jonathan; Kim, Dong-Youl; Goyal, Shivani; Wang, John M.; Lee, Jacob; Brown, Vanessa M.; LaConte, Stephen M.; Casas, Brooks; Chiu, Pearl H. (Elsevier, 2024-09-11)
Background: Aspects of reinforcement learning have been associated with specific depression symptoms and may inform the course of depressive illness. Methods: We applied support vector machines to investigate whether blood‑oxygen-level dependent (BOLD) responses linked with neural prediction error (nPE) and neural expected value (nEV) from a probabilistic learning task could forecast depression remission. We investigated whether predictions were moderated by treatment use or symptoms. Participants included 55 individuals (n = 39 female) with a depression diagnosis at baseline; 36 of these individuals completed standard cognitive behavioral therapy and 19 were followed during naturalistic course of illness. All participants were assessed for depression diagnosis at a follow-up visit. Results: Both nPE and nEV classifiers forecasted remission significantly better than null classifiers. The nEV classifier performed significantly better than the nPE classifier. We found no main or interaction effects of treatment status on nPE or nEV accuracy. We found a significant interaction between nPE-forecasted remission status and anhedonia, but not for negative affect or anxious arousal, when controlling for nEV-forecasted remission status. Limitations: Our sample size, while comparable to that of other studies, limits options for maximizing and evaluating model performance. We addressed this with two standard methods for optimizing model performance (90:10 train and test scheme and bootstrapped sampling). Conclusions: Results support nEV and nPE as relevant biobehavioral signals for understanding depression outcome independent of treatment status, with nEV being stronger than nPE as a predictor of remission. Reinforcement learning variables may be useful components of an individualized medicine framework for depression healthcare.
Stabilizing milk-derived extracellular vesicles (mEVs) through lyophilization: a novel trehalose and tryptophan formulation for maintaining structure and Bioactivity during long-term storage
Dogan, Alan B.; Marsh, Spencer R.; Tschetter, Rachel J.; Beard, Claire E.; Amin, Md R.; Jourdan, L. Jane; Gourdie, Robert G. (2025-01-13)
Extracellular vesicles (EVs) are widely investigated for their implications in cell-cell signaling, immune modulation, disease pathogenesis, cancer, regenerative medicine, and as a potential drug delivery vector. However, maintaining integrity and bioactivity of EVs between Good Manufacturing Practice separation/filtration and end-user application remains a consistent bottleneck towards commercialization. Milk-derived extracellular vesicles (mEVs), separated from bovine milk, could provide a relatively low-cost, scalable platform for large-scale mEV production; however, the reliance on cold supply chain for storage remains a logistical and financial burden for biologics that are unstable at room temperature. Herein, we aim to characterize and engineer a freeze-dried, mEV formulation that can be stored at room temperature without sacrificing structure/bioactivity and can be reconstituted before delivery. In addition to undertaking established mEV assays of structure and function on our preparations, we introduce a novel, efficient, high throughput assay of mEV bioactivity based on Electric Cell Substrate Impedance Sensing (ECIS) in Human dermal fibroblast monolayers. By adding appropriate excipients, such as trehalose and tryptophan, we describe a protective formulation that preserves mEV bioactivity during long-term, room temperature storage. Our identification of the efficacy of tryptophan as a novel additive to mEV lyophilization solutions could represent a significant advancement in stabilizing small extracellular vesicles outside of cold storage conditions.
Impact of Post-Traumatic Epilepsy on Mental Health and Multidimensional Outcome and Quality of Life: An NIDILRR TBIMS Study
Awan, Nabil; Weppner, Justin; Kumar, Raj; Juengst, Shannon; Dams-O'Connor, Kristen; Sevigny, Mitch; Zafonte, Ross; Walker, William; Szaflarski, Jerzy; Wagner, Amy (Mary Ann Liebert, 2025-01-06)
Traumatic brain injury (TBI) and subsequent post-traumatic epilepsy (PTE) often impair daily activities and mental health (MH), which contribute to long-term TBI-related disability. PTE also affects driving capacity, which impacts functional independence, community participation, and satisfaction with life (SWL). However, studies evaluating the collective impact of PTE on multidimensional outcomes are lacking. Thus, we generated a model to investigate how PTE after moderate-to-severe (ms)TBI affects TBI-associated impairments, limits activities and participation, and influences SWL. Of 5108 participants with msTBI enrolled into the National Institute for Disability, Independent Living, and Rehabilitation Research TBI Model Systems between 2010 and 2018 and with seizure-event data available at year-1 post-TBI, 1214 had complete outcome data and 1003 had complete covariate data used for analysis. We constructed a conceptual framework illustrating hypothesized interrelationships between year-1 PTE, driving status, functional independence measure (FIM), depression and anxiety, as well as year-2 participation, and SWL. We performed univariate and multivariable linear and logistic regressions. A covariate-adjusted structural equation model (SEM), using the lavaan package (R), assessed the conceptual framework’s suitability in establishing PTE links with outcomes 1-2 years post-injury. Multiple parameters were evaluated to assess SEM fit. Year-1 PTE was correlated with year-1 FIM motor (standardized coefficient, βstd = −0.112, p = 0.007) and showed a trend level association with year-1 FIM cognition (βstd = −0.070, p = 0.079). Individuals with year-1 PTE were less likely to drive independently at year 1 (βstd = −0.148, p < 0.001). In addition, FIM motor (βstd = 0.323, p < 0.001), FIM cognition (βstd = 0.181, p = 0.012), and anxiety (βstd = −0.135, p = 0.024) influenced driving status. FIM cognition was associated with year-1 depression (βstd = 0.386, p < 0.001) and year-1 anxiety (βstd = 0.396, p < 0.001), whereas year-1 FIM motor (βstd = 0.186, p = 0.003), depression (βstd = −0.322, p = 0.011), and driving status (βstd = 0.233, p < 0.001) directly affected year-2 objective life participation metrics. Moreover, year-1 depression (βstd = −0.382, p = 0.001) and year-2 participation (βstd = 0.160, p < 0.001) had direct effects on year-2 SWL. SWL was influenced indirectly by year-1 variables, including functional impairment, anxiety, and driving status—factors that impacted year-2 participation directly or indirectly, and consequently year-2 SWL, forming a complex relationship with year-1 PTE. A sensitivity analysis SEM showed that the number of MH disorders was associated with participation and SWL (p < 0.001), and this combined MH variable was directly related to driving status (p < 0.02). Developing PTE during year-1 after msTBI affects multiple aspects of life. PTE effects extend to motor and cognitive abilities, driving capabilities, and indirectly, to life participation and overall SWL. The implications underscore the crucial need for effective PTE management strategies during the first year post-TBI to minimize the adverse impact on factors influencing multidimensional year-2 participation and SWL outcomes. Addressing transportation barriers is warranted to enhance the well-being of those with PTE and msTBI, emphasizing a holistic approach. Further research is recommended for SEM validation studies, including testing causal inference pathways that might inform future prevention and treatment trials.
Emotional words evoke region- and valence-specific patterns of concurrent neuromodulator release in human thalamus and cortex
Batten, Seth R.; Hartle, Alec E.; Barbosa, Leonardo S.; Hadj-Amar, Beniamino; Bang, Dan; Melville, Natalie; Twomey, Tom; White, Jason P.; Torres, Alexis; Celaya, Xavier; McClure, Samuel M.; Brewer, Gene A.; Lohrenz, Terry; Kishida, Kenneth T.; Bina, Robert W.; Witcher, Mark R.; Vannucci, Marina; Casas, Brooks; Chiu, Pearl; Montague, P. Read; Howe, William M. (Elsevier, 2025-01-28)
Words represent a uniquely human information channel—humans use words to express thoughts and feelings and to assign emotional valence to experience. Work from model organisms suggests that valence assignments are carried out in part by the neuromodulators dopamine, serotonin, and norepinephrine. Here, we ask whether valence signaling by these neuromodulators extends to word semantics in humans by measuring sub-second neuromodulator dynamics in the thalamus (N = 13) and anterior cingulate cortex (N = 6) of individuals evaluating positive, negative, and neutrally valenced words. Our combined results suggest that valenced words modulate neuromodulator release in both the thalamus and cortex, but with regionand valence-specific response patterns, as well as hemispheric dependence for dopamine release in the anterior cingulate. Overall, these experiments provide evidence that neuromodulator-dependent valence signaling extends to word semantics in humans, but not in a simple one-valence-per-transmitter fashion.
Molecular Basis of Oncogenic PI3K Proteins
Sheng, Zhi; Beck, Patrick; Gabby, Maegan; Habte-Mariam, Semhar; Mitkos, Katherine (MDPI, 2024-12-30)
The dysregulation of phosphatidylinositol 3-kinase (PI3K) signaling plays a pivotal role in driving neoplastic transformation by promoting uncontrolled cell survival and proliferation. This oncogenic activity is primarily caused by mutations that are frequently found in PI3K genes and constitutively activate the PI3K signaling pathway. However, tumorigenesis can also arise from nonmutated PI3K proteins adopting unique active conformations, further complicating the understanding of PI3K-driven cancers. Recent structural studies have illuminated the functional divergence among highly homologous PI3K proteins, revealing how subtle structural alterations significantly impact their activity and contribute to tumorigenesis. In this review, we summarize current knowledge of Class I PI3K proteins and aim to unravel the complex mechanism underlying their oncogenic traits. These insights will not only enhance our understanding of PI3K-mediated oncogenesis but also pave the way for the design of novel PI3K-based therapies to combat cancers driven by this signaling pathway.
Rural-Urban Differences in the Determinants of Subjective Well-Being Among X/Twitter Users in the United States
Jiang, Wenting; Zhang, Mengxi; Wu, Connor Y. H.; Dong, Weichuan (Wiley, 2024-12)
Twitter Sentiment Geographical Index (TSGI) has been proposed to complement traditional surveys to measure subjective well-being (SWB) at the US county level. Our study aims to investigate determinants of TSGI-measured SWB in rural and urban US counties. Using the Classification and Regression Tree, we identified phenotypes or county-level characteristics associated with high SWB. Counties with newer homes were the top characteristic of high SWB in both urban and rural areas. Counties of the identical phenotypes tend to concentrate geographically, with the most favorable phenotypes clustered in the South. Random Forest analysis identified additional characteristics of high SWB, including higher population density in rural areas and lower real estate tax ratio in urban areas. Our results yield a comprehensive understanding of determinants of SWB at the local level, guiding evidence-based policy decisions and community initiatives to improve well-being in target populations.
Hyperammonemia and Ornithine Transcarbamylase Deficiency after Bariatric Surgery: A Retrospective Study
Pardo Lameda, Ivanesa L.; Wang, Eugene; Sharbaugh, Matthew; Lovette, Anyea; Shope, Timothy R.; Koch, Timothy R. (Mary Ann Liebert, 2024-07-17)
Background: The number of bariatric surgeries has risen in the past decades. Hyperammonemia related to ornithine transcarbamylase (OTC) deficiency is a potentially lethal disorder in patients with neurological symptoms. The apparent prevalence of OTC deficiency and potential predictors of mortality was examined in patients after bariatric surgery. Methods: This is a retrospective study of postoperative patients who developed hyperammonemia in a large, urban teaching hospital. Urinary orotic acid levels were ordered in individuals with elevated plasma ammonia. Results: Between January 2012 and August 2017, 1597 bariatric surgical procedures were performed. Seven women hospitalized with consistent symptoms had a mean peak plasma ammonia level of 155 umol/L (range: 57 to 273) and mean urinary orotic acid excretion of 3.3 mmol/mol creatinine (range: 1.6–7.9) after vertical sleeve gastrectomy, duodenal switch, or gastric bypass surgery, and there were four mortalities (57%). The apparent postoperative prevalence of OTC deficiency is 0.31%. Peak lactic acid (p = 0.011) level is a predictor of mortality. Conclusions: Hyperammonemia is associated with a high mortality rate predicted by high lactic acid levels. Postoperative prevalence of OTC deficiency is higher than the general population. Further investigations should examine potential mechanisms for its development.
Utility of the Non-Alcoholic Fatty Liver Disease Fibrosis Score in the Evaluation of Individuals with Medically-Complicated Obesity: A Retrospective Study
Nath, Anand; Shope, Timothy R.; Pardo Lameda, Ivanesa L.; Koch, Timothy R. (Bentham Science Publishers, 2024-10-02)
Background: Individuals with high body mass index (BMI) are at risk for chronic liver disease. Liver biopsy is a gold standard for the diagnosis of liver disease, as well as for determining the NAFLD activity score and fibrosis stage. Blood alanine aminotransferase (ALT) can support the presence of steatohepatitis, while the non-alcoholic fatty liver disease (NAFLD) fibrosis score (using clinical features and blood testing) may predict fibrosis. Based on prior studies, it is not clear whether the NAFLD fibrosis score is predictive of the NAFLD activity score or fibrosis stage. Aims: The aim was to examine whether clinical features and blood testing can identify the risk of chronic liver disease in those individuals with high BMI. Objective: Individuals with high BMI who may benefit from bariatric surgery were examined for the prevalence of steatohepatitis and for potential relationships between the NAFLD fibrosis score and the NAFLD activity score and fibrosis stage. Methods: This was a retrospective study of 593 consecutive individuals evaluated for bariatric surgery who underwent blood testing. Seventy individuals with a mean BMI of 49.9 kg/m2 underwent liver biopsy at surgery. Results: Elevated ALT was present in 102 subjects (17.2%). The correlation coefficient (R: 0.025; p = 0.83) between the NAFLD fibrosis score and NAFLD activity score was not significant, but there was a weak correlation between the NAFLD fibrosis score and fibrosis stage (R = 0.262; p = 0.28). Two individuals (3%) had cirrhosis. Conclusion: Elevated ALT may support the presence of liver disease in individuals with high BMI. There is a weak correlation between the NAFLD fibrosis score and the fibrosis stage. Further work is required to determine whether specific blood and clinical findings can be useful in making clinical decisions with regards to bariatric surgery in those individuals with high BMI.
Impact of Obesity Subtypes on Short-Term Weight Loss Following Vertical Sleeve Gastrectomy
Shah, Raj A.; Nath, Anand; Shope, Timothy R.; Pardo Lameda, Ivanesa L.; Brebbia, John S.; Koch, Timothy R. (BP International, 2024-11-27)
Background: Temporal prevalence studies of worldwide obesity have confirmed that this epidemic continues to worsen and investigators have suggested that the scope of this problem may indeed be underestimated. The pathogenesis of the condition is multifactorial and complex, and it has been suggested that early life exposure to environmental chemicals (termed obesogens) may be a major cause of this epidemic. Aims: Vertical sleeve gastrectomy has become the most common surgical intervention for medically-complicated obesity. This study was designed to examine the distribution of clinical subtypes of obesity (e.g. psychosocial factors, genetic risk, or obesogens) and to identify the best candidates for vertical sleeve gastrectomy based on clinical subtype. Study Design: This is a retrospective cohort study in a large, urban teaching hospital. Place and Duration of Study: Center for Advanced Laparoscopic & Bariatric Surgery, MedStar Washington Hospital Center Washington, DC between October 2018 and June 2019. Methodology: Consecutive new individuals (n=225) with medically-complicated obesity were evaluated preoperatively in an outpatient bariatric gastroenterology clinic. Subjects (n=17) were excluded. Eighty-four individuals underwent sleeve gastrectomy with a minimum of 6 months of postoperative follow up.
Combination Therapy Is Not Associated with Decreased Mortality in Infectious Endocarditis: A Systematic Review and Meta-Analysis
Farahani, Parisa; Ruffin, Felicia; Taherahmadi, Mohammad; Webster, Maren; Korn, Rachel E.; Cantrell, Sarah; Wahid, Lana; Fowler, Vance G.; Thaden, Joshua T. (MDPI, 2024-11-02)
Untreated infective endocarditis (IE) is uniformly fatal. The practice of combination antibiotic therapy for IE is recommended by treatment guidelines but largely unsupported by high-quality evidence. This study aimed to assess the efficacy of combination antibiotic therapy compared to monotherapy in IE through a systematic review and meta-analysis. We systematically searched MEDLINE, Embase, Cochrane, Web of Science, and CINAHL from inception to 29 July 2024. Studies reporting mortality outcomes of combination therapy versus monotherapy in adult patients with IE were included. Non-English papers and studies with less than 10 patients in the combination therapy group were excluded. Two reviewers independently assessed the studies and extracted relevant data. Summaries of odds ratios (ORs) with 95% confidence intervals (CIs) were evaluated using random-effects models. Out of 4545 studies identified, 32 studies (involving 2761 patients) met the inclusion criteria for the meta-analysis. There was no significant difference in the risk of all-cause mortality between the monotherapy and combination therapy groups (OR = 0.90; 95% CI = 0.67–1.20). Similar results were observed in subgroup analyses based on mortality time points, bacterial species, publication date, and type of study. Studies conducted in Europe reported a statistically significant decrease in overall mortality risk with combination therapy (OR = 0.67; 95% CI = 0.51–0.89), though this result was driven entirely by a single outlier study. Combination antibiotic therapy in patients with IE was not associated with reduced mortality.
Post-Operative Urinary Tract Infections After Radical Cystectomy: Incidence, Pathogens, and Risk Factors
Sandberg, Maxwell; Vancavage, Rachel; Refugia, Justin M.; Underwood, Gavin; Ye, Emily; Marie-Costa, Claudia; Rodriguez, Rainer; Prokopiou, Nicos; Bissette, Randall; Davis III, Ronald; Hemal, Ashok; Rodriguez, Alejandro R. (MDPI, 2024-11-12)
Background: The incidence of urinary tract infections (UTIs) after radical cystectomy (RC) with urinary diversion (UD), the typical pathogens, and associated patient risk factors have not been well documented. In this study, we examined the incidence of post-op UTIs after RC to identify associated risk factors. Methods: Single-center, retrospective case series of 386 patients with bladder cancer who underwent RC with UD between 2012 and 2024. The primary objective was UTI incidence, defined by the frequency of patients with urine culture with >10⁵ colony-forming units per high-powered field, spanning from post-op day 0 (POD0) to 90 days after discharge. Isolated pathogens were reported. Risk factors for UTIs were assessed. Results: The average age was 69 years old at surgery, and patients were predominantly male (80%). The cumulative incidence of post-op UTIs was 14%, among which 12 patients had more than one UTI. The UTI incidence was 2%, 8%, and 7% during the immediate post-op period, within 30 days, and within 31–90 days, respectively. Isolated pathogens included Escherichia coli (26%), Enterococcus faecalis (24%), Klebsiella pneumoniae (21%), and Pseudomonas species (21%). In the immediate post-op period, female sex was the only significant risk factor. At 31 to 90 days, cutaneous ureterostomy UD was the predominant risk factor for UTIs. For ileal conduit patients, those with a Wallace ureteral anastomosis were associated with UTI 31–90 days from discharge for RC. Conclusions: Our retrospective data suggests the incidence of UTIs and their causative pathogens after RC differ based on post-operative time points and vary according to different patient risk factors.
Assessing the impact of COVID-19 on outpatient psychiatric population well-being and symptomology utilizing COVID-19 Events Checklist (CEC) and Measurement Based Care
Jones, Sydney B.; Ko, Hayoung; Gatto, Alyssa J.; Kablinger, Anita S.; Sharp, Hunter D.; Cooper, Lee D.; Tenzer, Martha M.; O’Brien, Virginia C.; McNamara, Robert S. (2024-11-21)
Background: This study examines the impact of SARS-CoV-2 (i.e., coronavirus, COVID, COVID-19) using data from a measurement-based care (MBC) system utilized in an outpatient psychiatric clinic providing telemedicine care. A novel Patient Rated Outcome Measure (PROM), the COVID-19 Events Checklist (CEC) was administered in a hospital system based ambulatory clinic beginning April 2020 to track COVID-19-19’s impact on patients’ mental, emotional, and health-related behaviors during the pandemic. The study (1) provides descriptive CEC data, and (2) compares CEC results with PROMs evaluating anxiety (Generalized Anxiety Disorder-7; GAD-7), depression (Patient Health Questionnaire; PHQ-9), and psychological distress (Brief Adjustment Scale-6; BASE-6). Methods: This retrospective observational study included patient intake data collected from April 2020 to March 2021. Patient (N = 842) reports on the CEC’s five domain questions were aggregated to calculate average reports of COVID-19 related impacts at intake over the initial 12 months of the pandemic. Trends in COVID-19 related impacts were examined, and non-aggregated scores on the PHQ-9, GAD-7, and BASE-6 were compared to primary dichotomous (yes/no) CEC survey questions via Wilcoxon rank- sum testing. Results: Results capture the relationship between COVID-19 exposure, COVID-19- related sequelae and behaviors, and psychological symptom severity. Specifically, Wilcoxon rank-sum tests indicate that social determinants of health (SDOH), negative mental health impacts, and positive coping skill use were significantly associated with psychological symptomatology including overall psychological functioning via the BASE-6, anxiety via the GAD-7, and depressive symptoms via the PHQ-9. Results regarding SDOH were as follows: BASE-6 (w = 44,005, p < 0.001), GAD-7 (w = 44,116, p < 0.001), and PHQ-9 (w = 43,299, p < 0.001). Regarding negative mental health outcomes, the results were: BASE-6 (w = 38,374, p < 0.001), GAD-7 (w = 39,511, p < 0.001), and PHQ-9 (w = 40,154, p < 0.001). As the initial year of the pandemic elapsed, incoming patients demonstrated increased rates of suspected or confirmed exposure to COVID-19, (+2.29%, t = 3.19, p = 0.01), reported fewer negative impacts of COVID-19 on SDOH (−3.53%, t= −2.45, p = 0.034), and less engagement in positive coping strategies (−1.47%, t = −3.14, p = 0.010). Conclusions: Psychosocial factors related to COVID-19 are discussed, as well as opportunities for further research on the relationship between psychological symptomatology and the impact of COVID-19 on health-related behaviors.
The Off-Table Technique Increases Operating Room Efficiency in Direct Anterior Hip Replacement
Owen, Trevor M.; Hornberg, John V.; Corton, Kristoff; Moskal, Joseph T. (Elsevier, 2022-05-18)
Background: When performing a total hip arthroplasty via the direct anterior approach (DAA), many orthopedic surgeons utilize an orthopedic traction table. This technique requires an expensive table, time for positioning, staff to operate the table, and time-consuming transitions when preparing the femur. Some surgeons advocate for an “off-table” technique to avoid these difficulties. In this paper, we compare operating room efficiency between on-table and off-table techniques. Material and methods: We retrospectively reviewed patients undergoing total hip arthroplasty by a single surgeon across the transition from on-table to off-table DAA technique. Three cohorts were defined; the last 40 on-table hips, the first 40 off-table hips, followed by the second 40 hips. Timestamps from the operative record were recorded to calculate setup, surgical, takedown, and total room time. Implant fixation, patient demographic data, comorbidities, and complications were recorded. Results: From cohort 1 to 2, there was a 7-minute (14.44%, P = .0002) improvement in setup time but no change in total room time. From cohort 2 to 3, there was an additional 7-minute (15.47%, P < .0001) improvement in setup time, 32-minute (25.88%, P < .0001) improvement in surgical time, and 40-minute (21.96%, P < .0001) improvement in total room time yielding cumulative changes from cohort 1 to 3 of 15 minutes (27.68%, P < .0001), 28 minutes (23.11%, P < .0001), and 43 minutes (23.37%, P < .0001), respectively. There was no correlation between height, weight, or body mass index and time at any interval. Conclusion: Conversion to an off-table DAA technique offers an improvement in operating room efficiency. This is seen in setup, operative, and total room time. Implementation could allow for an additional case each day.
An evaluation of a new rapid qPCR test for the detection of 2019-novel coronavirus nucleocapsid (N1) gene in wastewater in Roanoke and Salem VA sewersheds
Lehrer, Lia W.; Lewis, Anna; Tolliver, Susan A.; Degen, Marcia; Singh, Rekha; Houser, Sara R.; Rao, Jayasimha (IWA Publishing, 2024-08)
The COVID-19 pandemic initiated public interest in wastewater-based epidemiology (WBE). Public and private entities responded to the need to produce timely and accurate data. LuminUltra and Hach partnered to provide a rapid, field-based quantitative polymerase chain reaction (qPCR) test for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in wastewater. This study evaluates the Hach GeneCount SARS-CoV-2 Wastewater RT-qPCR Assay Kit and LuminUltra GeneCount® Q-16 RT-PCR instrument. The Hach LuminUltra methods were compared to the Promega Wizard® Enviro Total Nucleic Acid kit and Bio-Rad CFX Opus 96 Real-time PCR Detection System. Over a 12-week period, wastewater samples were collected weekly from seven locations in the Roanoke/Salem, VA sewersheds. Concentration and extraction of the viral RNA were followed by qPCR analysis. The target gene for detection was the nucleocapsid gene (N1) of the SARS-CoV-2 virus. Costs, ease of use, time to produce results, sample preparation, and data comparisons were considered. The comparison determined that the Hach LuminUltra method and instrument were more affordable, consumed less time, and required less technical expertise. While the new method was specific, it had low sensitivity. This evaluation suggests the Hach LuminUltra method should be reserved for limited situations requiring onsite field analysis where data accuracy is not essential.
The absence of nosemosis in eastern bumblebees (Bombus impatiens Cresson) from regions of Roanoke and New River Valley
Samarasinghe, Binuk; Ausburne, Thomas; Blankenship, Christopher; Lin, Kaung; Linsenman, Kathleen; Rao, Jayasimha; Bhatta, Chet (2023-12-01)
In a study of 220 eastern bumblebee specimens collected from the Roanoke and New River Valley areas, PCR analysis of the gut lumen revealed the absence of Nosema spp. infections, challenging prevailing assumptions about their prevalence in bumblebee populations. The outcome underscores the need for further research to determine the factors contributing to this absence, including the unique ecological context of the study area. These findings highlight the significance of host susceptibility and survivability, emphasizing the complexity associated with parasite-host interactions within bumblebees.
Is Collagenase Worth the Costs?
Capito, Anthony E. (2024-10-19)
A Novel Outpatient Mental Health Clinic Addressing Patient Access, Teaching, and Team-Based Care
O'Brien, Virginia C.; Kurdila, Laura; Martin, Rachel K.; Nayani, Huma (2024-10-17)
Navigating Disparities in Dental Health—A Transit-Based Investigation of Access to Dental Care in Virginia
Kim, Junghwan; Karki, Shashank; Brickhouse, Tegwyn; Vujicic, Marko; Nasseh, Kamyar; Wang, Changzhen; Zhang, Mengxi (2024-10-30)
Objective: To identify vulnerable areas and populations with limited access to dental care in Virginia, the study aimed (1) to calculate travel time and accessibility scores to dental care in Virginia using a transit-based accessibility model for all dental clinics and dental clinics participating in the Medicaid dental program and (2) to estimate factors associated with accessibility to dental clinics participating in the Medicaid dental program in Virginia. Methods: The study used building footprints as origins of transit trips to dental care services (or destinations). The study then computed transit-based origin–destination travel time matrices based on the detailed trip information, including in-vehicle and out-of- vehicle travel time. Accessibility scores were calculated by counting the number of dental clinics that can be reached within 60 min. Regression analysis was used to measure factors associated with accessibility scores to dental clinics participating in Medicaid. Results: Residents in smaller regions spent longer travel time to dental clinics by public transit compared with those who resided in larger regions. Medicaid participants also faced longer travel time compared with the general population. Residents spent more than three-fourths of the time waiting for public transit and walking to clinics regardless of where they live and what type of insurance they have. Associations between sociodemographic factors and accessibility scores to dental clinics participating in the Medicaid dental program varied across regions. Conclusions: Disparities in dental care accessibility exist depending on the size of regions and Medicaid participation in Virginia. The disparities in transit-based access to dental clinics and a disproportionate amount of time spent waiting for public transit and walking to dental clinics could be improved through tailored interventions taking into account the sociodemographic and geographic characteristics of each region.

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