bluuebunny/crossref_metadata_2025 huggingface dataset:
Severe Diaphragm Fiber Weakness And Normal Response To Intraoperative Phrenic Stimulation In An ECMO‐Dependent Adult Receiving Lung Transplant
Authors: Smith Barbara K. , Machuca Tiago N. , Bresciani Guilherme , Mankowski Robert T. , Wohlgemuth Stephanie , Rackauskas Mindaugas , Pipkin Mauricio , Arnaoutakis George J. , Martin Tomas D. , Leeuwenburgh Christiaan , Ferreira Leonardo F. , Martin Daniel , Beaver Thomas M.
Published: May 2022

Introduction

Prolonged mechanical ventilation (MV) places patients at an increased risk for ventilator‐induced diaphragm dysfunction (VIDD), which can delay weaning from MV. We previously reported that intraoperative phrenic stimulation may preserve diaphragm fiber contractile function in those undergoing cardiac surgeries, but benefits are unclear in those with significant pulmonary disease who require extracorporeal membrane oxygenation (ECMO) support.

Case Description

A 55‐year‐old male with end‐stage pulmonary fibrosis underwent bilateral lung transplantation (LTX) after a two‐week pre‐operative hospitalization that included ECMO support. Phrenic stimulation commenced upon initial surgical exposure of the diaphragm, and supramaximal twitch stimulations were administered every 30 minutes to one hemidiaphragm over 136 minutes. The contralateral side served as an inactive control. Diaphragm biopsies of the LTX patient were acquired after 5 stimulations. Maximal single‐fiber diaphragm twitch force was then compared to nine male participants (56 (12) years) admitted for cardiac bypass or valvuloplasty surgery, who underwent 6 (1) bouts of unilateral intraoperative stimulation followed by diaphragm biopsy. In each subject, we tested maximal single‐fiber force on an average of 22 (4) slow‐ and 22 (3) fast‐twitch fibers.

Compared to cardiac surgical patients, the LTX subject had increased slow fiber cross‐sectional area (CSA) (Control side, cardiac: slow 5166 (1645) mm2; fast 6792 (732) mm2; LTX: slow 6827 (1504) mm2; fast 6159 (1173) mm2). Diaphragm fiber CSA of the stimulated side trended higher in the LTX patient (slow: 8588 (1908) mm2, p=0.080 vs control side; fast: 7232 (1976) mm2, p=0.094 vs control). Specific force (absolute force normalized to fiber CSA) in LTX was reduced by ~32% in slow fibers and ~30% in fast fibers (Table), as compared to cardiac patients. Specific force of stimulated fibers trended higher for slow‐ but not fast‐twitch fibers in LTX; response to stimulation resembled that of cardiac surgical patients. The patient was extubated 26 hours post‐LTX, as compared to 12 (7) hours in the cardiac patients.

Impact (Novelty and Importance)

This novel model of functional electrical stimulation suggests that phrenic stimulation preserved fiber CSA in an ECMO‐dependent adult with pulmonary fibrosis. Phrenic stimulation increased maximal specific force in slow‐twitch fibers, but responding forces remained well below expected values. These findings suggest that critically ill adult recipients of LTX may require additional duration and volume of diaphragm training, whether through voluntary or evoked contractions, to recover functional inspiratory muscle strength post‐operatively.
Changes to the Neurospora crassa metabolome as a result of defects in arginine catabolism
Authors: Urbanek Alexandra , McCollum Liam , Pollock Elizabeth
Published: May 2022

Arginine is a secondary source of nitrogen in many plant and fungal species. Non‐lethal mutations that impact arginine catabolism could cause secondary impacts on the metabolome as cells adjust to the lack of nitrogen availability via arginine. In this study, 1H nuclear magnetic resonance spectroscopy (NMR) was used to compare the metabolomes of Neurospora crassa grown in either minimal medium or arginine‐supplemented medium. A strain deficient in the arginase enzyme responsible for catalyzing the first step of arginine catabolism were metabolically distinct from wild‐type or urease strains grown under the same conditions. Arginase knock‐out strains also exhibited small changes in the composition of the amino acid pool, particularly alanine, when grown in minimal medium.
Left ‐ Right Asymmetry of the Jugular Foramen in Multisuture Syndromic Craniosynostosis
Authors: Woolridge Katherine , Mussell Jason C.
Published: May 2022

Introduction

Apert and Crouzon syndromes are among the most common craniosynostosis syndromes found in children. Mutations have been found in the fibroblast growth factor receptor 2 (FGFR2) gene in both syndromes. Although different mutations, the common mutated receptor raises suspicion for its involvement in the cranial morphogenesis found in these syndromic craniosynostosis patients.

The shapes of these children’s skulls have long been thought to be the result of early fusion of the synchondroses. The syndromic morphology of the skulls in these patients, in particular Apert, results from a combination of abnormal development of the skull base, neural tissue, and calvaria. Investigations of these effects has led multiple studies to find decreased volumes of the posterior fossa in craniosynostosis patients and effects on the basicranial foramina of the skull, in particular the jugular foramen.

Craniosynostotic children develop elevated intracranial pressure (ICP), as well as, other complications such as hydrocephalus and tonsillar herniation related to this increased pressure and skull dysmorphology. Narrowing of the jugular foramen is a potential cause of venous hypertension and may contribute to the ICP.

This study analyzes the size of the jugular foramina in an effort to relate the severity of the foraminal stenosis to timing of synchondroses fusion, seen earlier in Crouzon patients. Additionally, as right jugular foramina have been found to be larger than left in the general population, our study analyzes the right and left jugular foramen sizes in relationship to each other in each Apert and Crouzon patient.

Methods

Twelve preoperative CT scans of individuals diagnosed with either Apert or Crouzon syndrome were individually segmented and volume of the right and left jugular foramina estimated in Avizo. Volumes were analyzed using Wilcoxon Rank Sum and Kruskal‐Wallis one‐way ANOVA tests in SPSS. Scatter plots of the ratio of right to left foraminal volumes were created using Excel. This study was conducted under LSUHSC IRB #920.

Results and Discussion

Initial results found no significant differences between right and left jugular foramina, however, absolute measurement of volumes most often recorded larger volumes on the left, contrary to that seen in the normal population. Scatter plots revealed two distinct clusters based on ratio of left‐right asymmetry which may reflect a difference in diagnosis.
Systemic and local administration of vasopressin differently affect hemodynamic and respiratory parameters in normotensive and hypertensive rats
Authors: Proczka Michal , Trzciński Adam , Żera Tymoteusz
Published: May 2022

Introduction

Upregulation of vasopressinergic system and increased chemoreflex activity contribute to essential hypertension. Vasopressin (AVP) V1a receptors (V1aRs) were found in the brain stem structures involved in the control of breathing and in the carotid bodies (CBs). It has also been shown that in normotensive rats intravenous (i.v.) and local (intra‐carotid, i.a.) AVP administration results in different hemodynamic and respiratory response.

Purpose

We aimed at finding out how systemic (i.v.) and local (i.a.) administration of AVP affects cardiorespiratory system via V1aRs in normo‐ and hypertensive rats and if V1aRs are expressed in CBs in spontaneously hypertensive (SHR) and normotensive Wistar‐Kyoto (WKY) rats.

Methods

The study was performed on urethane‐anesthetized adult male WKY (n=7) and SHR rats (n=7). Animals were implanted with vascular catheters into femoral vein (i.v. infusions), femoral artery (hemodynamic parameters) and external carotid artery (local infusions), as well as the tracheal tube (respiratory parameters) and subcutaneous ECG electrodes. After obtaining baseline parameters, the arterial chemoreflex was triggered with i.v. administration of potassium cyanide (KCN) (30 μg/100 μL). Bolus of AVP was given i.v. (10 ng/100 μL) and i.a. (5 ng/50 μL). After stabilization of hemodynamic and respiratory parameters, V1a receptor was blocked by administration of V1aR antagonist (d(CH2)51,Tyr(Me)2,Arg8)‐Vasopressin; 5 μg/100 μL) and AVP and KCN infusions were repeated. After measurements, carotid bodies (CBs) were collected and immunostained for V1aRs and visualized with confocal microscopy.

Results

Resting mean arterial blood pressure (MABP), heart rate (HR) and minute ventilation (MV) were significantly higher in SHR rats than in WKY control. In both groups hemodynamic and respiratory response to pharmacological trigger of the reflex occurred, however increase in MABP and MV were significantly greater in SHR than in WKY rats. Intravenous AVP administration caused an increase in MABP, but ventilatory inhibition only in SHR rats. Intra‐arterial AVP infusion caused a modest increase in MABP in both groups, but inhibition of ventilation only in SHR rats. Blockade of V1aR abolished the effects of both systemic and local AVP administration. Furthermore, V1aR antagonist decreased the pressor component of the chemoreflex, however it did not influence ventilatory response. Immunostaining revealed V1aRs in CBs in both groups.

Conclusions

Our findings show that enhanced cardiorespiratory responses to activation of arterial chemoreflex and augmented pressor and ventilatory effects of systemic and local administrations of AVP are present in hypertensive rats and depend on V1aRs. Presence of V1aRs in CBs suggests that AVP may control cardiorespiratory system via arterial chemoreceptors.
The Genomics Education Partnership As A Model of Course‐Based Undergraduate Experience (CURE) that Promotes Growth Mindset
Authors: Tsotakos Nik , Hark Amy T. , Merkhofer Evan , Santisteban Maria , Lopatto David , Reed Laura
Published: May 2022

The Genomics Education Partnership (GEP) is a community of practice aiming to integrate genomics research into undergraduate curriculum while providing support to faculty in the process. It consists of more than 200 members in over 180 undergraduate institutions across the United States. Following training, faculty can claim annotations from one or more distinct projects (F element, Pathways, Parasitoid Wasps, Puerto Rican parrot) to integrate in their classes. Students participating in these projects annotate previously unstudied genomes, which are then used in analyses to answer specific scientific questions by the project lead faculty. Each of these projects is facilitated by curated curricula and customized online Bioinformatics tools. This approach has several advantages, including enabling faculty to scale research experiences to whole classrooms (unlike the wet lab apprentice model), the lack of safety issues, and the ease of transition to online delivery. Importantly, mistakes in annotations are not costly, and students can revisit their annotations to correct them. This makes the research amenable to peer instruction. While students may initially experience some frustration, they can consult with their faculty, their peers, and/or virtual teaching assistants to amend their errors. Thus, the GEP model allows for learning gains through a growth mindset, where abilities are developed through the research process. Faculty report that struggles are beneficial to the students, and that they are more likely to allow students to fail in a GEP research project than in wet lab/field work. Student outcomes are routinely assessed by a pre/post quiz and survey. While positive outcomes are observed overall, our current research indicates that these can be enhanced by early interventions that reinforce the nature of science and the agency of individual student researchers. The GEP always looks to grow its network of faculty and increase the diversity of the community.
Aggregated Alpha‐Synuclein Activates Pro‐Inflammatory NFKB Signaling Pathways Through TLR‐Dependent and Independent Mechanisms in Peripheral Monocytic Cells
Authors: Bearoff Frank , Dhavale Dhruva , Kotzbauer Paul , Kortagere Sandhya
Published: May 2022

Toll‐like receptors (TLRs) are pattern recognition molecules that induce inflammatory signaling cascades upon recognition of pathogen or damage associated molecules. In addition to peripheral immune cells including monocytes, TLRs are broadly expressed on cells of the central nervous system (CNS) including microglia, astrocytes, and neurons and their activation induces production of pro‐inflammatory mediators inducing neuroinflammation and neurodegeneration in the chronic state. Prolonged neuroinflammation in the substantia nigra (SN) leading to accumulation of alpha‐synuclein fibril (α‐syn) containing Lewy‐bodies (LBs) and ultimately death of dopaminergic neurons is a pathological hallmark of Parkinson’s disease (PD) and is thought to be a major mechanism driving disease progression. TLRs are an integral component of the feed‐forward neuroinflammatory loop where damage from neurodegeneration generates TLR ligands that further amplify the inflammatory circuit. Importantly, aggregate fibrillar α‐syn can interact with TLRs on microglia in the brain, of which TLR2 and 4 are best characterized; however, the extent to which fibrillar α‐syn interacts with peripheral immune cells including monocytes is poorly understood. Peripheral inflammation may play a causal role in inducing and perpetuating neuroinflammation and accumulation of fibrillar α‐syn has been reported at several peripheral sites including the gut and liver in PD. To model the peripheral immune response to fibrillar α‐syn we exposed THP‐1 monocytic cells in vitro to determine inflammatory signaling pathways altered by α‐syn. Compared to monomeric α‐syn, preformed‐fibrillar (PFF) α‐syn displays overt inflammatory gene upregulation and pathway activation as assessed by RNA‐Seq. Both MyD88 and TRIF mediated TLR signaling pathways were broadly overrepresented in the PFF condition as well as RNAK/RANKL signaling supported by large increases in NFKB signaling and pro‐inflammatory cytokine production including TNF and IL‐1B. These results indicate that α‐syn may act broadly across all TLRs and other pro‐inflammatory receptors such as RANK.
Modeling macrophage response to periodontal infections in vitro
Authors: Pandruvada Subramanya , Farrar Nico , Al‐Kakhan Waleed , Emecen‐Huja Pinar , Yilmaz Ozlem
Published: May 2022

Periodontal disease (PD) is a chronic inflammatory disorder characterized by the destruction of connective tissue, tooth loss and systemic infections. Numerous virulence factors derived from chronic opportunistic pathogens such as Porphyromonas gingivalis are responsible for enhanced microbial colonization, stimulation of inflammatory responses, and suppression of host defense response. Individuals with PD present with a complex array of inflammatory mediators, and cellular infiltration by neutrophils, lymphocytes and monocytes/macrophages. Although macrophages comprise 5–30% of cells in the cellular infiltrate of human periodontal lesions, how macrophage skewing contributes to PD, and more specifically in the downstream development of a macrophage immune response to oral bacteria are unclear. We, including others have investigated the activation of monocytes/macrophages, and discovered the means of type I vs. type II inflammatory activation vs. deactivation of macrophages both in vitro and in vivo. We have shown previously that P. gingivalis infection induces M1 macrophage formation, whereas opsonized‐P. gingivalis challenge was able to switch to M2‐like phenotype demonstrating macrophage plasticity. However, the mechanism of modulation and kinetics of macrophage inflammatory reactions during the process is unclear. Prior research in the field has failed to appreciate that it is the same monocyte/macrophage cell population which is initially polarized towards an effector “inflammatory” program and subsequently re‐polarized to the deactivation program not just in PD but in any inflammation. The overarching goal of our research is to understand how macrophage skewing contributes to PD, and the downstream development of immune response to PD‐associated bacteria towards development of new macrophage‐based therapeutics. Since macrophage polarization dynamics cannot be studied in an animal model, a reliable in vitro system is needed to provide fundamental insights into macrophage biology. We have developed an in vitro model that recapitulates different phases of the inflammatory response (recruitment, initiation, development and resolution), based on purified human peripheral blood monocytes exposed to a battery of microenvironmental cues mimicking macrophage polarization/depolarization in vivo and we have created a kinetic profile of polarization by RNA analysis. Further we have applied our model to macrophage/gingival fibroblast coculture system to study kinetics of polarization. And by comparing gene clusters that are differentially expressed in M1 and M2, we have successfully recapitulated the macrophage polarization kinetics of acute inflammatory and resolution phases during periodontal inflammation and validated the key inflammatory and transcriptional factors using RT‐PCR at different phases. In conclusion, we developed an in vitro model which can be further employed to test novel macrophage‐based therapeutics to treat periodontal disease.
Chronic Stress exacerbates Tau production in the 3xTg Alzheimer’s Disease Mice
Authors: Prabhu Saina , Burrage Emily , Simpkins James , Kelley Eric , Chantler Paul
Published: May 2022

Alzheimer’s disease (AD) is the most prevalent type of dementia linked with progressive cognitive decline and behavioral impairment in humans. Currently, an estimated 6.2 million Americans are living with AD, and it is ranked as the 6th leading cause of death in the United States. AD is a multifactorial disorder associated with protein alterations, oxidative stress and neuroinflammation. A cumulative of these factors drive the AD pathogenesis stimulating neurons to produce excessive amounts of β‐amyloid protein (Aβ1‐42) and hyperphosphorylated tau proteins. The complex interplay among the abnormal Aβ1‐42and tau proteins lead to the development of senile plaques and neurofibrillary tangles in the hippocampus of the brain. Chronic psychosocial stress is a risk factor of dementia and is mediated by a pro‐oxidative microenvironment, a fundamental process associated with dementia. We have shown that the xanthine oxidase pathway plays a key role in the chronic stress‐induced cerebrovascular pathology. Thus, we test the hypothesis that chronic stress, using the unpredictable chronic mild stress (UCMS) model, will exacerbate tau pathology and thus, accelerate the early progression of AD. Further, we tested the hypothesis that blocking the xanthine oxidase pathway with febuxostat (Feb) will prevent this accelerated progression of AD.

At 4 months‐of‐age, 3xTg mice were separated into 4 groups; AD control, AD control+Feb, AD+UCMS, AD+UCMS+Feb. UCMS was performed for 8 weeks, with or without Feb treated water (50mg/L). Mice were euthanized at 6 months‐of‐age and the harvested brains were flash frozen and stored at ‐80°C. Brains were homogenized to extract soluble and insoluble fractions of tau proteins using Western blot (WB) and normalized to GAPDH or B‐actin.

At 6 months‐of‐age, UCMS accelerated total and phosphorylated tau protein expression by 83% (p<0.05) and 350% (p<0.001), respectively, compared to AD controls. Febuxostat prevented the increased expression of phosphorylated tau and lowered the total tau protein expression in the UCMS group. However, total tau protein expression remained higher compared to AD control levels. Thus, overall, these data suggests that chronic stress accelerates tau pathology in 3xTg mice partly through the xanthine oxidase pathway. We will further explore Aβ1‐42and xanthine oxidase in 3xTg brain homogenates at 6 and 9 months‐of‐age, to better understand how stress accelerates AD pathology.
Segmental variability in the regulation of NKCC1 by aldosterone in rat proximal and distal colon
Authors: Nickerson Andrew J. , Rajendran Vazhaikkurichi M.
Published: May 2022

The corticosteroid hormone, aldosterone, markedly enhances K+ secretion throughout the colon – a mechanism critical to its role in maintaining overall K+ balance. Previous studies from our lab have demonstrated that basolateral Na+‐K+‐2Cl‐ cotransporter 1 (NKCC1) is transcriptionally up‐regulated by aldosterone in the distal colon specifically to support large conductance K+ (BK) channel‐mediated K+ secretion. This function is distinct from the more well‐established role of NKCC1 in supporting luminal Cl‐ secretion throughout the gastrointestinal tract. However, considerable segmental variability exists between proximal and distal colonic ion transport processes, especially concerning their regulation by corticosteroids. Although active K+ secretion has also been described in the proximal colon, the molecular identity of the K+ channel(s) that mediates aldosterone‐induced K+ secretion in the proximal colon is not known, nor is the involvement of NKCC1 in the process. Experiments were therefore designed to test the hypothesis that aldosterone up‐regulates NKCC1 in the proximal colon to support BK channel‐mediated K+ secretion, congruent with its effects in the distal colon. Using dietary Na+‐depletion as a model of secondary hyperaldosteronism in rats, we found that NKCC1 protein expression in the proximal colonic mucosa was enhanced 2‐fold (p < 0.05) by Na+ depletion (i.e., aldosterone), whereas mRNA abundance was unaffected (p = 0.32). Surprisingly, electrogenic K+ secretion was not detectable by short‐circuit current (ISC) measurements, in response to either basolateral bumetanide (NKCC1 inhibitor) or luminal Ba2+ (non‐selective K+ channel blocker), despite enhanced K+ secretion in Na+‐depleted vs. normal rats, as measured by 86Rb+ fluxes under voltage‐clamped conditions (net K+ secretion = ‐2.1 ± 0.6 vs ‐0.4 ± 0.2 mEq/cm2.hr; p < 0.05). Expression of both BK and intermediate conductance K+ (IK) channels was also found to be unaltered by dietary Na+ depletion, at both the protein and mRNA level. However, basal ISC (146.7 ± 16.8 vs. 93.7 ± 8.7 mA/cm2; p < 0.05), as well as bumetanide‐sensitive, Ca2+‐ and cAMP‐stimulated ISC (i.e., Cl‐ secretion) were significantly enhanced by dietary Na+ depletion (ΔISC = 239.6 ± 5.6 vs. 105.7 ± 33.5 and 154.3 ± 8.7 vs. 115.3 ± 8.7 mA/cm2 for Ca2+ and cAMP, respectively; p < 0.05 for both). In parallel to this was an increase in cystic fibrosis transmembrane conductance regulator (CFTR) Cl‐ channel protein expression (~1.7‐fold; p < 0.05). We therefore reject our original hypothesis and conclude that NKCC1‐dependent secretory pathways are differentially regulated by aldosterone in proximal and distal colon, where they are biased toward Cl‐ and K+ secretion, respectively. Development of therapeutic strategies in treating pathologies related to aberrant or altered colonic K+/Cl‐ transport – such as pseudo‐obstruction, ulcerative colitis, or end‐stage renal disease (ESRD) – may benefit from these findings.
A Preliminary Report on the Variation of Respiratory Blood Pressure during Sleep in Patients with Hypertension
Authors: Wang Jinan , Sun Xingguo , Tai Wenqi , Zhou Qingqing , Zhang Yanfang
Published: May 2022

Objective

Explore whether the blood pressure of hypertensive patients changes periodically with respiration.

Methods

This study analyzed 8 patients with hypertension without sleep apnea who performed cardiopulmonary exercise testing (CPET), polysomnography (PSG), continuous fingertip pulse wave and electrocardiogram (ECG), and compared with 8 normal subjects evaluated in the same period. Calculate the number of respiratory cycles (Bn), average respiratory cycle time (Bn‐T) and other respiratory parameters as well as systolic blood pressure (SBP), diastolic blood pressure (DBP), blood pressure variation cycles (BPV‐n), average blood pressure variation cycle time (BPV‐T) and other blood pressure variability parameters. Continuous variables within and between groups were compared by independent‐sample t test, and data calculated by different methods in the same group were compared by paired‐sample t test.

Results

The core parameters of CPET such as peak oxygen uptake (72.82±10.07%Pred) and anaerobic threshold (59.69±6.66%Pred) of hypertensive patients without sleep apnea were significantly lower than those of normal subjects (P<0.05). The fingertip pulse wave calculation of SBPV‐n (7000.25±1404.78) and DBPV‐n (6949.25±1407.98) in hypertensive patients were basically the same, similar to the results of normal subjects, and there was no statistically significant difference between the two groups (P>0.05); SBPV‐T, DBPV‐T, SBPV rate and DBPV rate (4.34±0.72 s, 4.37±0.70 s, 14.22±2.39 bpm, 14.10±2.34 bpm) were not statistically different from normal subjects (P>0.05); Bn/SBPV‐n (1.00±0.03) and Bn/DBPV‐n (1.01±0.02) are basically the same as normal subjects (P>0.05), and both are close to 1.SBPV‐n (2464.75±1318.38) and DBPV‐n (936.00±132.18) calculated based on pulse transit time during sleep were significantly lower than the fingertip pulse wave calculation parameter (P<0.01). The systolic blood pressure variation amplitude (2.96±0.83 mmHg) and diastolic blood pressure variation amplitude (2.57±0.38 mmHg) were greater than those of normal subjects, but the difference was not statistically significant.

Conclusion

The variability of blood pressure during sleep in hypertensive patients without sleep apnea is similar to variability of respiration, and the change trend is consistent with normal subjects, both blood pressure variability is caused by respiration.
Metabolic Effects of Sodium Fluorocitrate and Potential Treatments on Saccharomyces Cerevisiae: Changes in Oxygen Consumption
Authors: Racine Michelle , DeLey Cox Vanessa E. , Pueblo Erin , Jennings Laura , Tressler Justin , McCranor Bryan
Published: May 2022

Sodium fluoroacetate (1080) is a colorless, odorless, tasteless, water‐soluble metabolic poison. In the body, fluoroacetate is converted to fluorocitrate (FC) which blocks the citric acid cycle and drastically decreases ATP production. Symptoms of exposure include nausea, vomiting, abdominal pains, salivation, irrational fear, weakness, tachypnea, cyanosis, sweating, increased temperature, and death. Signs and symptoms of 1080 poisoning are nonspecific, further complicating the diagnosis. 1080 is tightly regulated within the United States, but it is commonly used in Australia, New Zealand, Mexico, Japan, South Korea, and Israel as a rodenticide to control invasive and predatory species. An eco‐terrorist scare in New Zealand (2015) and findings reported by the CIA (2007) have led 1080 to being identified as a potential terrorist weapon.

To identify potential countermeasures against 1080 poisoning, a Saccharomyces cerevisiae (yeast) model was selected to assess the impact of FC on cellular respiration and to screen candidate therapeutics. In response to FC, yeast showed depressed mitochondrial activity as measured by oxygen consumption rate (OCR). Potential treatments, thonzonium bromide, nifuroxazide, pyrvinium pamoate, menadione, mefloquine, clemastine fumarate, bisacodyl, L‐ascorbic acid, thiethylperazine and vinpocitine, were examined in this study. All treatments are approved by the Food and Drug Administration. Toxicity of each treatment was also assessed.

Assays were performed in yeast extract peptone galactose media, a metabolically restrictive media. To assess the effect of FC on OCR, cells were exposed to 50 µM, 100 µM, and 200 µM FC in liquid culture for 1, 4, or 24 hours. After incubation, mitochondrial respiration was assessed via the MitoXpress assay (Agilent), a fluorescence‐based assay that measures OCR. Once established as a viable model, yeasts were then used to screen therapeutics to improve cellular respiration. Yeast was co‐incubated with fluorocitrate (200 µM), and potential treatments at three increasing concentrations for 4 hours and the effects on mitochondrial respiration were assessed via the MitoXpress assay.

Following the decreased OCR in yeast exposed to FC, 6 of the 10 treatments successfully restored the mitochondrial function of yeast as demonstrated by an increase in OCR. As a result, the compounds nifuroxazide, pyrvinium pamoate, vinpocitine, clemastine fumarate, bisacodyl, and L‐ascorbic acid are moving forward for further testing in cardiomyocytes and hepatic spheroids, with potential in vivo assessment, to characterize their effectiveness against 1080 poisoning. Future studies will continue to use yeast as a valuable screening method to identify other potential treatments for sodium fluoroacetate.
Effects of Systemic Hypoxia on Motor Control Performance and Brain Blood Flow in Healthy, Young Humans
Authors: Kompa Paige , Reissman Megan , Reissman Timothy , Crecelius Anne R.
Published: May 2022

The brain is an oxygen dependent organ of the human body and adequate blood flow is imperative. To maintain adequate perfusion, in response to stimuli like hypoxia, vasodilation occurs. Fine motor control skills are essential, particularly for in‐flight piloting. Despite the possibility of encountering hypoxia in flight conditions, there is a lack of data on how motor control may be impacted by hypoxia and the corresponding changes in brain blood flow. We hypothesized that motor control would be impaired during hypoxia, despite increased cerebral blood flow. A group of seven subjects between the ages of 20 to 22 performed a motor control task in two counterbalanced conditions, the control (21% O2, 0.03% CO2, nitrogen balance) and the hypoxic exposure (10% O2 with nitrogen balance mix). The motor control task consisted of lateral joystick movements to adjust the angle of a computer visual beam to roll and stop a ball into one of 4 targets (40 targets total in MATLAB). Throughout each trial, heart rate (HR; 3‐lead ECG), beat‐beat arterial blood pressure (MAP; finger photoplethysmography), end‐tidal CO2 (sampling line) and bilateral middle cerebral artery velocity (MCAv; transcranial doppler), an indicator of cerebral blood flow (CBF), were measured. The motor control program recorded the time to target, beam angle, and ball velocity. In poikilocapnic conditions, hypoxic and normoxic gas mixtures were delivered via facemask and on average the subjects desaturated to an SpO2value of 84.1 ± 4.9%. Contrary to our hypothesis, hypoxia had minimal impact on motor control based on time to task completion for both individual trials and overall task (188.9 ± 21.9 s vs 194.7 ± 19.9 s p=0.613). Physiologically, as anticipated, hypoxia increased heart rate significantly in the transition from normoxic to hypoxic stimulus (86.1 ± 4.6 vs 75.7 ± 7.3 bpm; p<0.001) but was not significantly greater in hypoxic motor control (82.7 ± 9.0 bpm) than hypoxia alone (p=0.180). During the motor control task, MCAv (average of both sides) was similar in normoxic (51.6 ± 7.7 cm/sec) and hypoxic conditions (54.2 ± 8.7 cm/sec; p=0.414). However, MCA during hypoxic motor control was higher than that in hypoxic rest (49.1±10.3 cm/sec; p=0.025), whereas motor control during normoxia did not significantly increase MBV from rest (49.7 ± 7.4; p=0.17). Results were similar when analyzed based on cerebral vascular conductance (MBV/MAP). The present results suggest that mild systemic hypoxia does not impact performance in a simple motor control task, and this may be because of an increase in brain blood flow.
Curbing High‐Fat Induced Perturbations in Aortic Perivascular Adipose Tissue in Adolescent Male Sprague‐Dawley Rats: Soil as Therapy?
Authors: Mohr Alex E. , Sweazea Karen L.
Published: May 2022

Directly attached to the outer wall of blood vessels, perivascular adipose tissue (PVAT) is a unique variant of fat that is an important paracrine modulator of vascular physiology. Due to the proximity and endocrine‐like characteristics of this tissue, PVAT can contribute to the regulation vascular contractility and endothelial function. PVAT can also assume several properties of brown adipose tissue, including increased vascularization, small lipid droplet formation, mitochondrial density, and production of cardiometabolic signaling intermediates. Importantly, these properties promote the metabolic activity of this tissue which appear to be associated with improved vascular health. However, such properties may be diminished by chronic deleterious stimuli such as a high‐fat diet (HFD) and disease conditions like metabolic syndrome. Under such pressures, PVAT may serve a more insidious role in vascular dysfunction and promote the development of cardiovascular disease. Chronic diet‐induced changes in the vasculature and associated tissues like PVAT may be occurring early in the life cycle, promoting degeneration and disease‐associated remodeling. Currently, examination of these tissues early in life remain relatively unexplored and may offer important insight into the identification of prevention strategies and therapeutic targets. Previously, our lab identified increased expression of genes in the aorta of HFD fed adolescent Sprague‐Dawley rats, highlighting potential pathways and signaling intermediates that may impact the development of early vascular dysfunction. Moreover, we have demonstrated that an organic mineral complex (OMC) derived from plant and soil fractions prevented symptoms of metabolic syndrome in these animals. OMC is a complex of minerals, trace elements, organic acids (particularly fulvic acid), nitrates, and various microbial degradation products from plant and animal origins. The objective of the current study is to investigate the effects of a HFD and OMC on the expression of key proteins in aortic PVAT that play a role in adipose beiging, metabolism, and mitochondrial biogenesis, and are thus expected to provide critical insight into early mitigation of vascular disease progression. Six‐week‐old male Sprague‐Dawley rats (n = 36) were divided into two dietary groups: Chow or HFD fed for 10 weeks. Animals were further divided (n = 6/group) and administered 0, 0.6, or 3.0 mg/mL OMC in their drinking water. After the 10‐week intervention PVAT surrounding the aorta was extracted from the animals and Western blot analyses were performed using antibodies for the proteins UCP1, SDHA, PI3K, GLUT4, and b‐actin (as a loading control). Overall, we hypothesize that OMC supplementation will minimize decreases in these key proteins involved in health associated PVAT metabolism and function.
Exploration of Cytochrome P450 Structure and Function in In Silico Assays for Toxicity
Authors: Afolabi Joy
Published: May 2022

Cytochrome P450 (CYP or P450) enzymes are known for their role in detoxifying xenobiotics and may at times cause toxicity. CYP1A1gene polymorphisms have been linked to susceptibility risks of various cancers and neoplasms, including bladder cancer. The aim of the study was to use bioinformatics tools to examine structural differences in CYP1A1 wild type and isoforms 2 and 3. Protein sequences of selected CYPs were retrieved from the NCBI protein databank and GenPept. Sequence homologies were searched for by BLAST, and by multiple sequence alignments. Protein structural characteristics such as ligand binding and secondary structure prediction were analyzed by Phyre. The CYPIA1 wild type and isoforms had 33 % variation in their amino acid residues and binding sites. The predicted binding sites for the first 6 amino acid residues were similar between the wild type and isoform two; however, the average distances from the ligands differed. The predicted secondary structure of the CYP1A1 isoform 3 exhibited the widest difference from the wild type in the percentage of disordered helix (17%), alpha helix (66%), beta strand (3%) and trans‐membrane domains (12%). Differences in nucleotide sequence between the CYP1A1 wild type and isoforms caused a change in the protein structure which further altered the trans‐membrane topology and ligand binding potential of the protein. These findings indicate structural deficits among the three Cytochrome P450 isoforms, suggesting the possible conferment of risks to toxicity and associated diseases.
Investigating the Transition of the Core Centromeric Nucleosome Complex from Interphase to Mitosis using Chemical Biology Tools
Authors: Allu Praveen Kumar , Lackner Rachel M. , Chenoweth David M. , Black Ben E.
Published: May 2022

Centromeres are the location on each chromosome where kinetochores form in mitosis to connect to spindle microtubules that physically separate sister chromatids to the daughter cells. A 16‐subunit complex termed the constitutive centromere associated network (CCAN) is bound to nucleosomes harboring the histone variant, CENP‐A, and is essential for assembling the mitotic kinetochore. The core centromere nucleosome complex (CCNC) consists of CENP‐A nucleosomes and CCAN subunits, CENP‐C and CENP‐N. In prior studies, we proposed that the CCNC undergoes an alteration at mitotic onset where one of two copies of CENP‐N is lost. This model indicates that there would remain only one CENP‐A nucleosome surface with both CENP‐N and CENP‐C that is competent to recruit the CCAN and, in turn, assemble the kinetochore. We hypothesize that the asymmetric surfaces on CENP‐A nucleosomes provide a level of organization of centromeric chromatin that is important for chromosome segregation. We are developing a system to study these functional relationships in cells using chemical biology approaches. We have created a cell line with complementary SNAP and HALO tags on the CCNC components and employed the SNAP‐HALO cross linker, HaXS8, to tether CCNC components (CENP‐A with CENP‐N) irreversibly on nucleosomes. Initial experiments indicate that this system is able to retain CENP‐N at high levels on mitotic centromeres in an HaXS8 concentration‐dependent fashion. This provides additional support for the model of a centromeric chromatin transition as cells enter mitosis, and our system holds promise to test predictions that arise from it.
Unequal and Unique contribution of Different Adverse Childhood Experiences to Metabolic Disease Risk in a Multiracial Cohort
Authors: Leachman Jacqueline R. , Heier Kory , Lei Feitong , Ahmed Nermin , Dalmasso Carolina , Duncan Meredith S. , Loria Analia S.
Published: May 2022

Adverse childhood experiences (ACEs) are an independent risk factor for chronic disease, including obesity and metabolic syndrome. Therefore, we sought to determine the association of ACEs with BMI and plasma metabolic biomarkers affecting a multiracial cohort. Total ACE score was calculated in 38,353 non‐Hispanic Black and White men and women who participated in the second follow‐up of the Southern Community Cohort Study (2012‐2015). We used regression analyses to assess whether total ACE score or individual ACE components were associated with BMI and included interaction terms to evaluate if the association differed by sex or race, and for female participants, we accounted for menopause status. Total ACE score was associated with BMI (non‐linear p‐value=0.0026) and differed by sex and race (interaction p‐value<0.0001), but not menopause status. BMI steadily increased with cumulative ACEs among Black women. Among White women, BMI sharply increased from 0 to 1 ACEs, and steadily increased thereafter. In White men, BMI increased as ACEs increased from 0 to 3 and remained relatively stable among individuals with >4 ACEs. In Black men, BMI decreased with cumulative ACEs. Among Black women, emotional and sexual abuse were associated with higher BMI (p<0.05). Including both Black women and men, having an incarcerated family member was associated with lower BMI. Physical abuse was associated with increased BMI in Black and White men, while emotional neglect was associated with increased BMI in White women (p<0.05). In addition, regression analysis revealed an association between total ACE score and waist circumference, total

cholesterol, the ratio of leptin to adiponectin, HbA1c, and insulin. Furthermore, with increasing number of ACEs, Black men were the most affected in waist circumference, showing a 6 cm overall increase; however, they showed reduced BMI. This data indicates increased visceral fat deposition which is an indicator of metabolic syndrome and insulin resistance. Using a mouse model of postnatal neglect, and in line with this data, we have found that female mice, and not male mice, develop exacerbated adiposity. Specifically, female mice display increased whitening of adipose tissue via the actions of the mineralocorticoid receptor on lipid storage and adipocyte differentiation. Overall, ACEs are associated with BMI, but each ACE component has a unique contribution to this effect that varies based on sex and race. Future pre‐clinical studies should aim to model sex‐ and race‐specific effect of ACE on the development of obesity to provide insights on potential personalized therapies for people undergoing these health disparities.
Chronic Exposure to Sublethal Concentrations of Aquatic Nitrite Change Nose and Gut Morphology and Associated Microbiomes in Channel Catfish
Authors: Franklin Ashley , Ortiz Whitney , Matthews Michael , Prangnell David , Carlos‐Shanley Camila , Huertas Mar
Published: May 2022

Nitrite is a common pollutant that can enter waterways via agricultural runoff or build up in aquaculture ponds when nitrogenous waste is converted to nitrite. Preliminary studies by the Huertas lab found that exposure to sublethal concentrations of aquatic nitrite alters the microbiome of goldfish and bioaccumulates in the olfactory epithelia, gills and brain. These studies also showed a negative impact on the olfactory tissue of exposed fish, which could lead to higher susceptibility to nasal pathogens. Our objective is to assess nitrite bioaccumulation in tissues and the alteration of the microbiome in the key aquaculture species channel catfish (Ictalurus punctatus). We hypothesize that the relative abundance and diversity of bacteria in the nose and gut microbiomes of channel catfish will be altered due to elevated nitrite exposure and that nitrite will bioaccumulate in tissues.

Channel catfish were exposed to 0 mM (control), 0.2 mM, and 2 mM concentrations of nitrite. A total of six 500 liter tanks were used in a two‐phase experiment. For phase one, 16 fish per tank were placed into three 0 mM nitrite tanks and three 2 mM nitrite tanks. The 2 mM fish were kept for 12 hours before sampling. For phase two, 24 of the phase one control fish were placed into three 0.2 mM tanks and the remaining 24 control fish were left in the three control tanks for a total of 8 fish per tank. Phase two lasted 30 days with sub‐samplings at day five and 30. All fish were sampled for nose, gut, muscle, gill, brain, blood, liver, and kidney tissues for biochemical, microbial, or histological analysis. Upon dissection, fish from the 2 mM tanks exhibited marked methemoglobinemia due to nitrite‐induced oxidation of hemoglobin. The mortality rates were 0.04%, 0.08%, and 92% for the control, 0.2 mM, and 2 mM treatments respectively. The nose and gut microbiomes will be sequenced using whole genome shotgun sequencing to determine the microbial composition and measure changes in relative abundance. Histological analysis showed oxidative damage in all tissues from individuals exposed to 2 mM and partial damage in tissues of the 0.2 mM treatment.

Because the microbiome is a powerful barrier against pathogens, disruption of the microbiome could lead to higher rates of disease infection and transmission in fish. Alteration of the nasal microbiome may increase mortality from the bacteria that cause septicemia in catfish, Edwardsiella ictaluri, whose common routes of infection are the nose or gut. Changes to the microbiome could be the missing link between nitrite and increased susceptibility to E. ictaluri infections in intensive farming. In the long term, this research aims to provide guidelines for water quality management in order to decrease the rate of bacterial infection and transmission in aquaculture systems.
The Effects of Acute Cannabidiol on Autonomic Balance
Authors: Razanouski Zachary , Corcoran Andrea
Published: May 2022

A recent poll indicates that at least one third of Vermont state’s population has used hemp‐based products such as Cannabidiol (CBD). This non‐psychoactive compound is one of 700 chemicals derived from the Cannabis sativa plant and is both legal and widespread for distribution in the state of Vermont, however very little work has been done to investigate its physiological effects at recreationally‐relevant doses. We hypothesized that in apparently healthy adults, acute CBD favorably affects the autonomic nervous system and that this would be evident by an increase in heart rate variability (HRV). HRV is a non‐invasive method used to analyze autonomic balance. Though scientific studies are lacking, anecdotal reports of athletes self‐administering CBD have indicated a positive effect on HRV. Using a randomized, double‐blind, placebo‐controlled crossover study, we examined a narrow age range of adults (average 20.9 ± 0.3 yrs), administered varying acute recreationally‐relevant doses of CBD (0, 25mg, 50mg, 200mg), and characterized baseline cardiovascular variables (heart rate, blood pressure, HRV) at rest. Results indicate that such doses do not affect resting heart rate or blood pressure, however increasing dose appears to increase standard deviation of interbeat intervals (SDNN) and root mean square of successive differences (RMSSD). Such changes reflect an increase in HRV, indicative of elevated parasympathetic activity. This work contributes to the framework of understanding potential therapeutic uses and/or risk factors of CBD, particularly as it relates to healthy individuals.
Effects of cinnamon extract on sirtuin activity: potential for metabolic regulation blood glucose control
Authors: Stockert Amy , Speck Cecilia , Smith Courtney
Published: May 2022

Sirtuins (SIRTs) are a family of enzymes that are involved in several metabolic and inflammatory pathways in diseases. Sirtuins are histone‐deacetylase enzymes which remove an acetyl group from lysine residues in histone proteins. Acetylation of histones plays a role in epigenetic regulation of gene expression. Recent studies demonstrate that SIRT enzymes can regulate fasting glucose, concentration of circulating insulin, insulin resistance, pancreatic activity, and inflammation. Metabolic parameters, like glucose homeostasis and chronic inflammation, contribute to the development of diseases like type 2 diabetes mellitus (T2DM). Increasing expression of SIRT can aid in the regulation of these metabolic parameters and may be involved in diseases like T2DM. Our research aims to analyze the activity of HDACs and SIRT in 3T3L‐1 cells. 3T3L‐1 cells were grown in bovine calf serum and nuclear extracts were collected using a nuclear extraction kit. Nuclear extracts were then analyzed for protein concentration and added to the Epigenase™ Universal SIRT Activity/Inhibition Assay Kit. The data collected suggests that cinnamon does alter the activity of SIRT and further research will be explored to determine the extent to which this effect proves useful in the treatment of T2DM.