bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Live‐Firefighting on Ventricular‐Vascular Coupling in Middle‐Aged Firefighters
Authors: Hibner Brooks Aaron , Schroeder Elizabeth C. , Lefferts Wesley K. , Lane-Cordova Abbi D. , Horn Gavin P. , Smith Denise L. , Fernhall Bo 
Published: April 2020

IntroductionCardiovascular events are a leading cause of line of duty‐related death among firefighters. Increased risk potentially manifests from detrimental changes in ventricular function, vascular load, or their interaction defined as ventricular‐vascular coupling (VVC). Young firefighters exhibit ventricular‐vascular uncoupling after live firefighting, however it is unknown whether higher‐risk, middle‐aged firefighters respond similarly.PurposeDetermine the effect of live fire‐firefighting on ventricular function, vascular load, and VVC in middle‐aged firefighters (40–60 yr).MethodsEighteen middle‐aged male firefighters (48±5 years, 28±4.9 kg·m−2) underwent hemodynamic and cardiac measures before and 10 minutes after an 18‐minute bout of intermittent, high intensity live‐firefighting activities in personal protective equipment. Blood pressure (BP), left ventricular function (ejection fraction [EF]), ventricular elastance (Elv: end systolic pressure [ESP]/end systolic volume [ESV]), and vascular load, defined as arterial elastance (Ea: [ESP]/stroke volume [SV]) were measured. VVC quantified as the ratio of Ea to Elv.ResultsFollowing a single bout of high intensity, intermittent live‐firefighting activities, mean arterial pressure and ESP decreased while heart rate increased (see table
). EF, Elv and Ea were maintained, and VVC was preserved.ConclusionApparently healthy middle‐aged firefighters maintained the balance between ventricular function and vascular load following a single bout of live‐firefighting. Therefore, impaired VVC may not be related to the increased cardiovascular risk during a single bout of live‐firefighting in apparently healthy middle‐aged firefighters. Further investigations should examine the effect of an extended firefighting bout on ventricular function, vascular load, and VVC in individuals with cardiovascular disease risk factors.
Changes in cardiovascular parameters pre/post firefighting activity.

Pre

Post

p

SBP (mmHg)

132 ± 11

123 ± 10

<0.01

DBP (mmHg)

81 ± 6

79 ± 6

0.06

MAP (mmHg)

98 ± 7

94 ± 6

<0.01

HR (bpm)

65 ± 10

85 ± 11

<0.01

SV (ml)

85 ± 18

76 ± 15

0.11

EDV (ml)

126 ± 29

122 ± 27

0.40

ESV (ml)

43 ± 16

46 ± 17

0.40

ESP (mmHg)

102.6 ± 8.9

97.7 ± 6.7

<0.01

EF (%)

66.1 ± 6.9

63.0 ± 7.1

0.12

Ea (mmHg/ml)

1.3 ± 0.3

1.4 ± 0.2

0.24

Ely (mmHg/ml)

2.8 ± 1.0

2.5 ± 0.8

0.33

VVC

0.5 ± 0.1

0.6 ± 0.2

0.08

SBP: systolic blood pressure, DBP: diastolic blood pressure, MAP: mean arterial pressure, HR: heart rate, SV: stroke volume, EDV: end diastolic volume, ESV: end systolic volume, ESP: end systolic pressure, EF: ejection fraction, Ea: arterial elastance, Elv: ventricular elastance, VVC: ventricular‐vascular coupling
Translational Regulation of Cyclooxygenase‐2 (COX2) by Cyclin‐Dependent Kinase 7 (CDK7) in Endothelial Cells
Authors: Shetty Shruthi , Spaulding Amelia M. , Baker Cassadie , Baine Stephen H. , Hoyt Dale G. 
Published: April 2020

Endothelial cell prostaglandins modulate the response to inflammatory stimuli. Combined treatment with E. coli endotoxin and interferon‐γ (LPS/IFN) induces cyclooxygenase‐2 (COX2) mRNA and protein. Modulation of COX2 expression may be therapeutically useful in different inflammatory states. Given the induction of COX2 mRNA by LPS/IFN, it was hypothesized that depletion of the transcription‐stimulating enzyme, cyclin‐dependent kinase 7 (CDK7), would antagonize induction of COX2. Here, mouse aortic endothelial cells were treated with CDK7 or non‐targeted siRNA, followed by LPS/IFN. Contrary to our expectations, knocking down CDK7 super‐induced the expression of COX2, without affecting mRNA or turnover of the protein. This suggested that CDK7 depletion increased protein synthesis. Here, signaling mechanisms known to regulate translation were investigated. CDK7 knockdown increased phosphorylation at Serine 209 of the mRNA cap‐binding translation initiation factor, eIF4E. Knockdown also increased cap‐binding activity of eIF4E. CDK7 depletion increased phosphorylation of the eIF4E repressor, 4EBP1, and decreased its association with eIF4E. Finally, increased phosphorylation of ribosomal protein S6 (RPS6), a component of the 40S ribosomal subunit, was also seen in the absence of CDK7, indicating increased translation. The results suggest that CDK7 represses COX2 expression by limiting translation through effects on RPS6, eIF4E and/or 4EBP1. CDK7 may serve as a target for the manipulation of COX2 expression in endothelial cells.Support or Funding InformationSupport was received from the Popat Patil Fellowship (SS).
APC Controls Wnt‐Induced β‐catenin Destruction Complex Recruitment in Human Colonocytes
Authors: Parker Taybor William , Neufeld Kristi Lynn 
Published: April 2020

Wnt signaling is essential for intestinal homeostasis and is aberrantly activated in the majority of colorectal cancers (CRC). In over 80% of CRC, the tumor suppressor Adenomatous Polyposis Coli (APC) is mutated, resulting in expression of a truncated protein product. APC is a key component of the β‐catenin destruction complex, which maintains low cellular levels of β‐catenin but is inhibited following Wnt ligand presentation. The precise mechanism underlying β‐catenin destruction complex inhibition is not clear, nor is the exact role of APC in the complex. APC is primarily considered a core component of the destruction complex but has been shown to have other roles involving β‐catenin nuclear import/export and cytoskeletal functions. Here, we use Wnt3a beads to study the response of endogenous Wnt components to a local Wnt cue. Using three CRC cell lines, each with a different Wnt pathway status, we demonstrate that localized Wnt redistributes pathway components toward the Wnt source in the presence of full‐length, but not truncated APC. Further, use of the Wnt3a‐beads to perform protein pull‐down demonstrates that APC and β‐catenin both associate with the Wnt‐beads. APC depletion in nontransformed human colon epithelial cells diminishes this Wnt‐induced redistribution. Our results suggest revision of the current model as follows. In response to Wnt, the β‐catenin destruction complex: 1) maintains composition and binding to β‐catenin, 2) translocates to the plasma membrane, and 3) requires full‐length APC for this membrane trafficking. Currently, work is being performed to uncover mechanistic insights into the role of APC in destruction complex reorientation to a Wnt3a signal.Support or Funding InformationThis study was supported by the National Science Foundation [grant number IOS‐1456538] and by the National Institutes of Health [P30CA168524].
Essential Anatomy for Neurology and Psychiatry in the Undergraduate Medical Curriculum
Authors: Harmon Derek , Harrell Kelly , Keim Sarah , Topping Daniel , Sanky Charles , Laitman Jeffrey , Reidenberg Joy S. , Farias Anna , Lopez Lisa , Zumwalt Ann , Mork Amy , Wineski Lawrence , Cotter Megan , Brooks William , Davies David , Royer Danielle , Marzban Hassan , Notebaert Andrew , Martindale Jim , Hankin Mark 
Published: April 2020

Introduction. To prepare medical students for clinical training and practice, it is critical to understand the anatomical knowledge considered most important for different clinical specialties.Aim. To address this issue, a consortium of anatomists in the US and Canada is collecting data from clinical educators in Neurology and Psychiatry clerkships and electives to identify the anatomy they consider essential.Methods. An IRB‐approved, online survey (Qualtrics, Seattle, WA) was used to assess the importance of 98 anatomical topics in seven body regions. The study first examined the percentage of Neurology and Psychiatry clinical educators (clerkship/elective directors and attending physicians) that considered each anatomical region important to their specialty. Second, the study examined the rank assigned to each anatomical topic using an ordinal scale from 1 (not important) to 4 (essential).Results. At the time of abstract submission, data had been collected from 39 Neurology clinical educators at 11 medical schools and 19 Psychiatry clinical educators at 9 medical schools. The percentage of clinical educators that considered each anatomical region important to their specialty were (highest‐to‐lowest): Neurology – Back (97%), Upper Limb (97%), Lower Limb (97%), Head & Neck (97%), Thorax (54%), Pelvis & Perineum (46%), and Abdomen (31%); Psychiatry – Head & Neck (89%), Back (47%), Abdomen (37%), Thorax (32%), Upper Limb (26%), Lower Limb (26%), Pelvis & Perineum (16%). Further data analysis has identified the highest ranked anatomical topics in each body region for the Neurology and Psychiatry clerkships/electives.Discussion and Conclusion. This database provides detailed information regarding the most clinically relevant anatomical topics as identified by Neurology and Psychiatry clinical educators. This information can aid in focusing preclinical learning to best prepare medical students for success in their undergraduate and graduate clinical experiences.
Connections between the RNAPII degradation, DNA damage response, and mRNA processing
Authors: Hofler Alex , Skidders Morgan , Moore Claire , Nazeer Fathima 
Published: April 2020

Eukaryotic cells have evolved multiple mechanisms to deal with DNA damage in order to prevent disease. In the presence of helix distorting DNA damage, RNA polymerase II (RNAPII) blockage at damage sites can lead to RNAPII degradation and activation of the DNA damage response (DDR), if the damage is not repaired promptly. Our hypothesis is that proteins involved in RNAPII degradation, such as Elc1, Def1 and Rpb9 in yeast, are also involved in regulating the DDR and other related cellular processes like mRNA maturation in response to DNA damage. Our data suggest that Def1 and Rpb9 could be involved in activating the DNA damage response through Rad53 (a protein involved in DNA damage signaling) while Elc1 is involved in blocking mRNA maturation after UV‐type DNA damage. We are currently exploring the role of Rpb9 and Def1 in regulating mRNA maturation following helix distorting DNA damage, using a PCR based assay. We will present these unexpected interconnections between RNAPII degradation, the DNA damage response, and mRNA processing.Support or Funding InformationKilmer Grant for AH. Presidential Scholars Funding for AH. Kilmer Grant for MS. Research Grant and Sponsorship for FN.
Indoxyl Sulfate Exposure inhibits Vascular Smooth Muscle Cell migration and Potentiates Vascular Injury
Authors: Carr Sean , Okon Imoh , Zou Ming-hui 
Published: April 2020

IntroductionChronic Kidney Disease (CKD) has been implicated in cardiovascular complications. CKD results in decreased filtration and a concomitant increase in uremic toxins. Uremic toxins are a by‐product of organic molecules, including two prominent amino acid derivatives, namely Indoxyl sulfate (IS) obtained from tryptophan and p‐Cresyl sulfate from tyrosine. Of these uremic toxins, IS has been shown to be highly potent, and implicated in exacerbation of multiple cardiovascular diseases. However, the effect of IS during vascular injury and specific contributions of Vascular Smooth Muscle Cells (VSMCs) remain unclear.MethodsTranswell migration and cell attachment assays were employed to examine the phenotypic effects of IS on VSMCs. Western blot analysis, gene silencing, and Immunofluorescence microscopy were utilized to examine the effects of IS on focal adhesion and actin related proteins.ResultsExposure of VSMCs to IS resulted in the formation of stress fibers and cytoskeletal disorganization. In the presence or absence of chemoattractants, we observed decreased migration of IS‐treated cells. Additionally, a noticeable reduction in cell area and cell attachment was evident. This led to investigation of focal adhesion, and actin‐related proteins due to their established roles in cell migration. It was determined that Focal Adhesion Kinase (FAK) and Paxillin were significantly decreased after prolonged exposure to IS. Immunofluorescence microscopy confirmed decreased FAK and Paxillin intensity at the cell periphery of IS‐treated cells. To determine whether FAK or Paxillin were the main effectors of decreased cell migration instigated by IS, gene silencing was performed. Relative to Paxillin, loss of FAK expression correlated with a reduction VSMC migration.ConclusionThese data suggest that IS contributes to alterations to focal adhesion related proteins, which in turn attenuates cell migration. IS induced loss of FAK potentiates reduced migration. Thus, IS‐induced inhibition of vascular repair may contribute to secondary complications in a subset of CVD patients.Support or Funding InformationNational Institutes of Health
The Search Continues: Determination of a Lipid Raft Targeting Motif in Cytochromes P450
Authors: Fuchs Robert , Reed James , Backes Wayne 
Published: April 2020

Cytochromes P450 play an essential role in metabolism of both xenobiotics and endogenous compounds. The liver P450s responsible for drug metabolism are predominantly expressed in hepatocytes, where they closely associate with the endoplasmic reticulum (ER). This membranous organelle is mostly composed of phospholipids, which can assemble into disordered regions (ld) or ordered regions (lo, “lipid rafts”).Our group previously showed that different P450 species show strong preference for either ordered or disordered regions. When expressed in human embryonic kidney (HEK) cells, we demonstrated that CYP1A2 is found in ordered (raft) regions, and that CYP1A1 exhibits a strong preference for the disordered region. This pattern was striking, as the two P450 species have over 70% sequence homology. We then showed that a chimeric CYP1A2 construct containing the first 107 amino acids of CYP1A1 no longer localized in the ordered regions, but mobilized to the disordered region. These findings indicate that a P450 raft targeting sequence exists within the first 107 amino acids of CYP1A2.The length and composition of this motif remain unclear. We hypothesize that a 5–9 amino acid sequence within the first 107 amino acids is responsible for the localization of CYP1A2 into the ordered domains, and that substitution of the corresponding region of CYP1A1 can mobilize full‐length CYP1A2 to the disordered region. To test this, we generated 5‐ to 30‐amino acid chimeras using overhang PCR cloning and expressed these constructs in HEK cells. The disordered membrane regions from these cells were solubilized using Brij98, with the ordered regions remaining in the membrane. The ordered membranes were isolated as a pellet after centrifugation at 100,000 x g for 1 h. We found that insertion of the first 28 amino acids of CYP1A1 into CYP1A2 led to its partial relocation into the disordered regions, and that the first 30 amino acids led to more complete relocation of the chimeric protein. We then generated smaller chimeras in an effort to identify the minimum amino acid segment responsible for membrane relocation. Substitution of amino acids 28–30 led to relocation of CYP1A2 from the ordered to disordered regions. These results demonstrate that a raft‐targeting sequence resides within the first 30 N‐terminal amino acids of CYP1A2 and, when eliminated, permits mobilization of the P450.Support or Funding InformationSupported by NIH GM123253 and ES013648 and by a predoctoral fellowship from the PhRMA Foundation.
“Smac”ing the Life out of XIAP
Authors: Greig James , Akteke Elfin , Doshi Sarah , He Eva , Fujikawa Kento , Lawrence Katya , Feberova Natalie , Hayashi Miwa , Jia Rizhe , Jin Maggie , Leha Emily , Powter Morgan , Shen Delphine Jiameng , Walker Samuel , Korneluk Robert 
Published: April 2020

X‐linked inhibitor of apoptosis protein (XIAP) is a key prosurvival protein that blocks apoptosis by inhibiting both the intrinsic and extrinsic pathways. Released by the mitochondria when under stress, XIAP is a homodimer, with 2 sets of repeating type I and type II baculoviral IAP domains: BIR1, BIR2 and BIR3, and RING. XIAP has a capacity to block apoptosis by directly inhibiting caspases 3,7 and 9. Second mitochondria‐derived activator of caspases (Smac) is a 184 amino acid chain. Smac antagonizes XIAP by attaching to the BIR3 domain inhibiting the binding of caspase‐9. Synthetic Smac mimetics (SMs) have been designed to duplicate the N‐terminal tetrapeptide (AVPI) or the IAP‐binding motif (IBM). Our model aims to show two BIR3 domain of a homodimer XIAP, bound to the IAP‐binding motif (IBM) of a Smac dimer. Selective antagonism of XIAP, specifically the BIR3 by Smac/SMs or monotherapy is not enough to kill cancer cells, however, it could be combined with immunotherapy, specifically virotherapy. This tricks the immune system to think that the cancer cells have a virus, which stimulates the immune antiviral response and creates an overproduction of immune cells known as a “cytokine storm”, to kill cancer cells.Support or Funding InformationThe Ashbury College MSOE Center for BioMolecular Modeling SMART Team used 3D modeling and printing technology to examine structure‐function relationships between Smac and BIR3 of XIAP.
The Effects of XIAP on Alzheimer's Disease
Authors: MacGillivray Brendan Cameron , Cobo Nicolas Alonso , Bai Kathleen , Efraim Margaret , Fu Celine , Fu Henry , Fujikawa Ayaka , Goodall Lauchlann , Han Brian , He Lucy , Hernandez-Oviedo Isabela , Ilianu Richard , Muscant Rebecca , Niu Catherina , Ramirez Victoria , Samad Hana , Ticala Iza , Wang Oscar , Wong Andrew , Korneluk Robert 
Published: April 2020

Inhibitor of apoptosis proteins (IAPs) prevents programmed cell death by interfering with the activation of caspases that cleave cytoskeleton fibres. X‐chromosome‐linked inhibitor of apoptosis protein (XIAP) is believed to be the most potent natural apoptosis inhibitor in the IAP family, as it effectively suppresses both intrinsic and extrinsic pathways of apoptosis. XIAP is characterized by three Baculoviral IAP Repeat (BIR) domains, a ubiquitin‐associated (UBA) domain, and one Really Interesting New Gene (RING) domain. The BIR‐2 domain binds with caspases 3 and 7, whereas the BIR‐3 domain binds with caspase 9.XIAP is closely associated with several neurodegenerative disorders, including Alzheimer’s Disease (AD), which affects over 44 million individuals worldwide. AD is characterized by the formation of ß‐amyloid plaques and tau tangles, which obstruct nutrients from reaching the nerve cells and result in cell death. Caspases cleave tau proteins that consequently collapse into tangles. Since XIAP prevents the activation of caspases, a lower level of XIAP leads to the acceleration of nerve cell death and cognitive impairment. While XIAP is unable to arrest tangle formation, an increase of XIAP will lessen cognitive decline.Support or Funding InformationThe Ashbury MSOE Center for BioMolecular Modeling SMART Team used 3D modelling and printing technology to examine the effects of the XIAP BIR‐3 and BIR‐2 domains on the caspases that interact with the Alzheimer’s pathway.
Does lysine acetylation affect water permeability of the collecting duct?
Authors: Hyndman Kelly Anne , Davis Parker , Mendoza Luciano Deven 
Published: April 2020

We recently reported that there are > 400 proteins in the inner medullary collecting duct that are post‐translationally lysine acetylated (ac‐K). Although historically, ac‐K proteins were thought to be predominantly histone proteins in the nucleus, we now know that all cellular compartments are enriched with ac‐K proteins. Pathway analyses determined that ac‐K proteins are enriched in various physiological processes such as glycolysis and vasopressin‐mediated water reabsorption. We recently identified the basolateral water channel, aquaporin‐3 (AQP3), as undergoing lysine acetylation (AQP3 K282). Thus, the purpose of this study was to determine if ac‐K AQP3 affects water permeability. We developed antibodies to specifically detected ac‐K AQP3 or total AQP3. In both male and female mice, ac‐K AQP3 was expressed in the basolateral membrane of the cortical and outer medullary collecting duct. However, following 24 h of water deprivation, ac‐K AQP3 was also found in the inner medullary collecting duct. Next, we developed AQP3 K point mutation plasmids, with K282Q representing an acetylated mimic, and K282 representing a deacetylated mimic. These constructs were stably expressed in vasopressin‐responsive mouse cortical collecting duct cells (AQP3mpkCCDs). Using the cell volume sensitive dye, calcein, water permeability of these mutant cells was determined following an osmotic stimulus. We found the acetylated mimic (K282Q) had the highest water permeability followed by the AQP3 wild type K282 cells and the deacetylated mimic (K282R). Finally, using CRISPR/CAS we engineered whole body point mutation mice. The K282Q mutant mice and littermate controls (K282) all developed normally. As adults, K282Q mice presented with elevated plasma osmolality (307 ± 2 mOsm/Kg H2O vs 298 ± 4 mOsm/kg H2O, P = 0.04) at baseline. Following 3 days of hydration with 5% sucrose water, K282Q produced twice as much urine as controls during their active period (2.16 ± 0.5 ml/12h vs 0.88 ± 0.2, P = 0.03). Moreover, when challenged with a 2 ml sterile water i.p., K282Q mice excreted majority of the water load within the first 3 h, while controls reached peak urine flow after 3 h. Finally, we quantified AQP2 (the apical water channel) and AQP3 mRNA expression and protein abundance. AQP2, AQP3 and AQP4 mRNA expression was similar between control and mutant mice. Surprisingly, K282Q mutant mice presented with significantly less AQP2 and AQP3 protein abundance compared to controls. Thus, mutating K282 in vivo resulted in a loss of AQP3 (a potentially AQP2) stability, and highlights the importance of this lysine residue. To conclude, lysine acetylation of AQP3 is a novel posttranslational modification that may regulate AQP function and water permeability in the collecting duct.Support or Funding InformationK01DK105038, R03DK120503, the University of Alabama at Birmingham Pittman Scholarship, NIH P30 DK074038