bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resting Sympathetic Transduction in Young Healthy non‐Hispanic Black Women: Potential Race and Sex Differences
Authors: Stephens Brandi Y. , Young Benjamin E. , Nandadeva Damsara , Skow Rachel J. , Grotle Ann‐Katrin , Vranish Jennifer R. , Greaney Jody L. , Brothers R. M. , Fadel Paul J. 
Published: May 2022

BackgroundThe prevalence of hypertension (HTN) is highest in the non‐Hispanic Black (BL) population. Notably, BL women have an equal or greater HTN prevalence compared to BL men; however, limited studies have included women. Heightened sympathetic nervous system reactivity has been proposed as a potential mediator of elevated HTN risk in the BL population. In this regard, our laboratory previously demonstrated exaggerated sympathetic transduction at rest in young normotensive BL men compared to their non‐Hispanic white (WH) counterparts. Whether similar responses are present in BL women is not known. Furthermore, whether there are sex differences in sympathetic transduction in young BL adults remains unclear.HypothesisWe hypothesized that BL women would exhibit elevated resting sympathetic transduction compared to WH women, and that sympathetic transduction would be comparable between BL women and men.MethodsSix young healthy BL women (age: 20 ± 1 years), six WH women (age: 21 ± 1 years) and six BL men (age: 21 ± 1 years) were studied. Heart rate (ECG), muscle sympathetic nerve activity (MSNA; peroneal microneurography) and beat‐to‐beat blood pressure (BP; Finometer) were continuously measured under resting conditions for 19 ± 1 min. Sympathetic transduction was quantified as peak changes in mean arterial pressure (MAP) and the nadir of total vascular conductance (TVC) over 10 cardiac cycles following spontaneous bursts of MSNA using signal‐averaging. All data are expressed as mean ± SEM.ResultsResting BP and heart rate were not different between groups (all P > 0.05). Likewise, BL women had similar MSNA burst frequency (BL women: 12 ± 2 vs. WH women: 14 ± 1 bursts/min; P = 0.475) and burst incidence (BL women: 21 ± 2 vs. WH women: 24 ± 2 bursts/100 cardiac cycles; P = 0.477) compared to WH women, and BL men (13 ± 1 bursts/min, 21 ± 1 bursts/100 cardiac cycles; P = 0.539). For peak increases in MAP following MSNA bursts, there were no differences between BL and WH women (BL women: Δ+2.3 ± 0.4 vs. WH women: Δ+2.1 ± 0.2 mmHg; P = 0.741). Peak reductions in TVC were also not different in women (BL women: Δ‐2.1 ± 0.3 vs. WH women Δ‐2.4 ± 0.6 mL/min/mmHg; P = 0.966). However, in comparison to BL men, BL women had lower MAP (women: Δ+2.3 ± 0.4 vs. men: Δ+5.5 ± 1.1 mmHg; P = 0.011) and TVC (P = 0.036) responses.ConclusionContrary to our hypothesis, these preliminary data suggest similar beat‐to‐beat sympathetic transduction at rest in BL and WH women. Interestingly, sympathetic transduction at rest was lower in BL women compared to BL men highlighting a potential differential effect of sex on BP regulation in young BL adults. Collectively, these findings suggest that augmented sympathetic transduction is not likely an early contributor to the greater prevalence of HTN in BL women.
Development of Tumor‐selective Transmembrane Peptides to Promote the Activity of the Receptor Protein Tyrosine Phosphatase J by Disrupting its Homodimerization
Authors: Rizzo Sophie , Sikorski Eden , Hart Will , Gerristen Jacqueline , Lazzarra Matthew , White Forest , Thévenin Damien 
Published: May 2022

Receptor Protein Tyrosine Phosphatases (RPTPs) are one of the most important regulators of receptor tyrosine kinases (RTKs) and therefore play a crucial role in mammalian signal transduction. But our still‐incomplete understanding of the structural aspects of their regulation and the lack of selective agonists have hampered efforts to understand their roles in downstream signaling regulation, and to pursue them as potential therapeutic targets. However, the reported ability of RPTP homodimerization to antagonize their catalytic activity presents potential opportunities to develop unique strategies to modulate the activity of RPTPs.We recently reported (Block et al., JBC, 2019; doi:10.1074/jbc.RA119.010229) that the homodimerization of a representative member of the RPTP family (protein tyrosine phosphatase receptor J or PTPRJ; also known as DEP1) is regulated by specific transmembrane (TM) residues, and that these interactions are essential in regulating its enzymatic activity and substrate access in cells.Building on these new insights and in response to the lack of selective agonists, we present here the design and testing of a novel class of tumor‐selective peptide capable of binding to the TM domain of PTPRJ and disrupting its homodimerization. By doing so, it promotes PTPRJ TM‐mediated access to EGFR, reduces the phosphorylation of EGFR (a known substrate) and other downstream signaling effectors, and antagonizes EGFR‐driven cancer cell phenotypes.This class of peptide represents a novel allosteric and a possibly orthogonal way to target the activity of PTPRJ and RTKs phosphorylation. It could therefore be used not only as probes to tease out PTPRJ regulating mechanisms but also for therapeutic purposes via the attenuation of signaling by dysregulated RTKs.
Investigating the Role of PKC‐delta in Voltage‐Independent Contractile Pathways in Mouse Resistance Arteries
Authors: Haghbin Nadia , Richter David M. , Kim Michelle S. , Welsh Donald G. 
Published: May 2022

Vascular smooth muscle cells (VSMCs) tune blood flow delivery through G protein‐coupled receptor (GPCR) associated signaling pathways and two general contractile mechanisms. The first, electromechanical coupling ties membrane potential (VM) to cytosolic [Ca2+] via voltage‐sensitive L‐type Ca2+ channels. The second—independent of voltage—centers on mechanisms of Ca2+ sensitization via Rho kinase and Protein Kinase C (PKC). While untested, agonists presumably activate both, with their relative contribution remaining static across concentration range. We hypothesize that voltage‐dependent mechanisms proceed voltage‐independent, and this order is contingent on the mode of agonist application.Mouse mesenteric/cerebral arteries mounted in a pressure myograph (60 mmHg) were globally or focally exposed to GPCR agonists (U46619 and Phenylephrine) and vasomotor responses, intercellular [Ca2+] levels, and VM monitored. Global application of either agonists increased arterial tone in a concentration dependent manner. Subsequent Nifedipine (L‐type Ca2+ channel blocker) application attenuated constrictive responses, particularly at the lower agonist concentrations. The remaining voltage‐independent constriction was blocked by Calphostin C (PKC inhibitor). While these findings highlight a hierarchical arrangement (voltage‐dependent preceding voltage‐independent), this order is not static. Stimulating a reduced number of VSMCs through focal agonist application, induces localized vasomotor responses that do not conduct across the arteriole or alter intercellular [Ca2+] or VM. Such focal responses could bypass electromechanical coupling owing to insufficient charge to change VM. Thus, this response is heavily dependent on Ca2+ sensitization mechanisms. Western blot analysis indicates that PKCα and PKCδ are likely the key regulatory isoforms in agonist‐induced constriction. Ongoing work is focused on translocation of PKCα and PKCδ and phosphorylation state of their key downstream targets including MYPT1, CPI‐17, Caldesmon, and HSP27.In summary, our findings reveal a hierarchical but malleable contractile arrangement in VSMCs whereby voltage‐dependent signaling precedes voltage‐independent, as long as sufficient smooth muscle cells are activated. These findings are of particular translational value to the pathobiology/management of cerebral vasospasm.
Determining Biomarkers of Myosteatosis for Sarcopenia and Cachexia Using MRI and Ultrasound
Authors: Rush Benjamin , Lortie Jevin , Osterbauer Katie , Garlapati Sujay , Campbell Toby , Traynor Anne , Leal Ticiana , Lee Kenneth , Reeder Scott B. , Kuchnia Adam 
Published: May 2022

BackgroundLung cancer patients have low survival rates resulting in over 131,000 deaths in the US in 2021. Muscle health decline from sarcopenia and cachexia increases the risk of death among patients with lung cancer. Though muscle mass is often used for sarcopenia diagnosis and non‐tissue specific weight loss is typically used for cachexia diagnosis, both conditions have no consensus definitions. Therefore, the need for quantitative biomarkers that reflect muscle health changes due to aging and weight loss is critical to mitigate sarcopenia and cachexia. We propose using highly accurate MRI‐based proton density fat fraction (PDFF) as a reference measure of muscle health to develop bedside ultrasound measures as biomarkers of muscle health. We hypothesized that PDFF is associated with ultrasound‐based echointensity (EI) and shear wave elastography (SWE), and that all three modalities are sensitive to muscle health differences between healthy young, healthy older, and older adults undergoing treatment for lung cancer.MethodsWe compared muscle health operationalized as myosteatosis in the mid‐thigh of the rectus femoris using ultrasound‐based brightness‐mode for EI, ultrasound‐based SWE for tissue elasticity, and MRI‐based PDFF for percent fat, which was the reference measure. We compared the 3 measures among young healthy (n=10), older healthy (n=10), and older adults with non‐small cell lung cancer (n=10) in a cross‐sectional pilot study. We also compared non‐myosteatosis measures including subcutaneous adipose tissue thickness and rectus femoris thickness via ultrasound, whole‐leg cross‐sectional area via MRI, and BMI between groups and between myosteatosis measures. We used ANOVAs with Tukey post‐hoc comparisons to assess muscle health between groups and Pearson correlations to determine muscle health measure associations between imaging modalities.ResultsWe found young healthy adults had significantly lower PDFF than older healthy adults and older adults with lung cancer (0.33% vs 2.83% vs 2.93%, respectively; p=0.001). Young adults also had significantly lower EI than older healthy adults, but not older adults with cancer (48.58 vs 81.81 vs 75.35; p=0.008). When comparing between measures, PDFF was highly associated with EI (r=0.62, p<0.001) and moderately inversely associated with SWE (r=‐0.41, p=0.025) but not BMI, rectus femoris thickness, or rectus femoris cross‐sectional area.ConclusionPDFF was sensitive to myosteatosis differences between young and both older adult groups. EI was less sensitive to myosteatosis differences between groups, yet EI was highly associated with PDFF unlike BMI. Our results suggest that the ultrasound measures could serve to determine muscle health at the bedside and are more sensitive to muscle health differences than BMI, which could improve interventions for cachexia and patient outcomes.
Integrated Streaming of Anatomy Dissection during Lecture Hours
Authors: Nonabur Venkatesh , Weitzel Sarah E. , Rarey Kyle E. 
Published: May 2022

Streaming of live faculty anatomy dissections was utilized to teach clinically relevant gross anatomy to first‐year Physician Assistant students during the summer of 2021 to correlate lecture with relevant dissection part. The online anatomy dissections by faculty were integrated with PowerPoint presentations before onsite dissection laboratory periods by the students.MATERIAL AND METHODSThe PA students viewed the dissections via zoom sessions during lecture hours coordinated by lecture presenter. During their six weeks of study, each session was scheduled for one hour lecture, followed by 3 hours of dissections. At the beginning of each session, ten quiz questions relative to prior sessions were asked to enhance students’ retention and recall. Following the daily online practical quizzes, students watched step by step dissection and power point lecture integrated with relevant slides and/or cross‐sections. During three hour laboratory time of each daily session, students were divided into small groups to dissect anatomy region for that day assisted by faculty member. Sixty four percent of the PA Class of 2023 completed an anonymous electronic survey at the conclusion of the course.The online survey of the enrolled PA students (n=40) in their first‐year training identified that the online dissections and the teaching format were extremely beneficial to their learning. Ninety seven percent of the students strongly agreed or agreed that the streaming of anatomy dissections was helpful in learning the assigned anatomy. Ninety five percent of the students strongly agreed or agreed that integrated power point presentations were beneficial, and Ninety five percent of the students strongly agreed or agreed that daily integrated quizzes (self‐assessment modules) were beneficial for their retention and recall. Although setting up online dissections and integrating the streaming dissections with relevant power points were time‐intensive, the teaching faculty viewed the online teaching experiences as effective means to further develop students’ knowledge base of anatomy education.
Measurement of Betaine‐Homocysteine Methyltransferase Activity via Fluorescent Detection of Free Thiols
Authors: Spiegelberg Bryan D. , Robinson Zaria 
Published: May 2022

High concentrations of homocysteine correlate with early onset heart disease and other disorders. The enzyme betaine‐homocysteine methyltransferase (BHMT) consumes homocysteine by transferring a methyl group from betaine to the free thiol group of homocysteine to form methionine. BHMT activity in turn can cause an imbalance of betaine, leading to other health issues like fatty liver and digestive disorders. Clearly, then, understanding the activity and regulation of BHMT can lead to insights into several key health problems. Unfortunately, currently available in vitro BHMT enzyme assays include the use of NMR or HPLC and thus are either slow or not readily scalable.Our goals are to create a new high throughput in vitro assay to measure BHMT activity and to implement this assay to better understand the enzyme’s regulation. This new assay utilizes the dye monobromobimane (mBBr), which becomes fluorescent upon conjugation to a free thiol group. The free thiol of BHMT substate homocysteine is consumed upon methylation; mBBr fluorescence, then, serves as a quantitative reporter of the progress of the BHMT reaction. We have confirmed that mBBr detects the model thiol, L‐cysteine, in a 96‐well plate format, and we can detect sub‐nanomolar amounts of homocysteine deprotected from commercially available DL‐homocysteine thiolactone. This assay has been used to follow the progress of BHMT activity and to investigate the effects of several potential inhibitors. The development of a simple fluorescent assay will enhance the speed of study of this and related enzymes and could spur high throughput searches for small molecule modulators.
Distinct Responses in the Brain Compared to Lung in a Rat Model of Fat Embolism Syndrome
Authors: Gibson Lilian , Mittal A. , Qureshi F. , Neerumpa S. , Hamidpour S. , Mateescu V. , Salzman G. , Molteni A. , Monaghan Nicholas P. , Poisner A. 
Published: May 2022

Fat embolism syndrome (FES) caused by release of emboli into the bloodstream after surgery or injury, can lead to severe neurological complications. We have previously shown that FES induced in rats by intravenous injection of triolein (T) causes pulmonary pathology after 48 hours that persists up to 10 weeks. Elevated expression of markers in the Renin Angiotensin System (RAS) are associated with pulmonary damage, and RAS inhibitors reduce pulmonary damage 1‐4. All components of the system (renin/ACE/AngII/AT1R) have been reported in the Central Nervous System and shown to be involved in neuroinflammation and eventual neurodegeneration5. To investigate the role of the brain RAS in response to FES, brains of T treated, and control rat models were examined for markers of RAS and neural pathology.Methodology24 rats received intravenous 200ul of T or Saline (S). Organs were processed at 48 hours or 10 weeks, sectioned, and immunostained with antibodies to Renin and Prorenin receptors in RAS; Glial Fibrillar Acidic Protein and Ib1a to identify makers of inflammation; Parp1 and Phospohistone S10 to identify cell death and proliferation respectively. Images were coded, blinded and quantified and statistically compared using GraphPad software.ResultsAs previously reported, lungs exhibited inflammation, vasculitis, and fibrosis at 48 hours and 10 weeks1,2. A significant increase in fat emboli was observed in the brain at 48 hours with persistence of micro‐emboli up to 10 weeks (S, N=6, relative emboli proportion (REP) = 7.2; FES N=5, REP = 11.0, p<0.001). Contrary to the lung, vasculitis was not observed in the brain after 48 hours or 10 weeks (S, vs FES, 48 hours, p<0.25; 10 weeks p<0.35). Regional differences (hippocampus, cerebellum, cerebral cortex, hypothalamus) in expression of markers of RAS and markers of inflammation were observed in T versus S samples at 48 hours and 10 weeks.ConclusionThis study highlights differences in organ responses to FES and identifies distinct regions in the brain that may be susceptible to FES. Adaptations of components of brain RAS have been linked to increased oxidative stress through activation of NADPH oxidase and production of reactive oxygen species in the brain5. Release of reactive oxygen species and activation of inflammatory mediators is shown to be associated with progression of neurodegeneration and cognitive dysfunction5. Understanding the acute and long‐term impacts of FES on localized brain RAS, could provide further insight into the susceptibility and resistance of other organs RAS response.References1. McIff et al., (2010). J. Orthop. Res., 28: 191‐197.2. Poisner et al., J Trauma Acute Care Surg. 2012 Apr;72(4):992‐8.3. McIff et al., J Trauma. 2011 May;70(5):1186‐1191.4. Fletcher et al., (2017). J Trauma Acute Care Surg. 2017 Feb;82(2):338‐344.5. Abiodun et al., Saudi Journal of Biological Sciences, (2020), 27: 905–912.
Implication of integrins in eptifibatide interference with platelet stimulation of ovarian cancer
Authors: Isingizwe Zitha Redempta , Kennedy Amy L. , Sjoelund Virginie , Benbrook Doris M. 
Published: May 2022

SignificanceA third of ovarian cancer patients have high platelet counts at diagnosis resulting in reduced survival compared to patients with low/normal platelet counts. Current studies suggest that platelets and ovarian cancer induce each other in a feed‐forward loop.Objective and HypothesisThe objectives were to: 1) evaluate differences in platelet counts and aggregation between healthy and newly‐diagnosed ovarian cancer patients; 2) develop an experimental model of the pathological interactions between platelets and ovarian cancer spheroids; and 3) identify pathways affected by these interactions and ways to intervene. Our hypothesis is that high platelet counts of ovarian cancer patients are associated with hypercoagulability, and inhibiting platelet aggregation reduces platelet‐mediated effects on ovarian cancer spheroids.Materials and MethodsComplete blood count was evaluated between healthy controls and newly‐diagnosed ovarian cancer patients before treatment. A platelet aggregation assay was performed to assess platelet physiology between the two groups. The molecular mechanism of platelet effects on ovarian cancer spheroid properties was evaluated using mass spectrometry and bioinformatics analysis of a magnetic 3D cancer spheroid assay, in the presence and absence of eptifibatide, a potent platelet inhibitor.ResultsWhile ovarian cancer patients had significantly higher platelet counts than healthy controls, platelet aggregation profiles and parameters were similar between the two groups. Incubation of platelets with cancer spheroids altered spheroid size and density in an eptifibatide‐sensitive manner. Co‐incubation of platelets with ovarian cancer spheroids activated the LXR/RXR pathway, a known down‐stream effector of the integrin receptor that eptifibatide targets.ConclusionPlatelet count does not predict platelet hypercoagulability in ovarian cancer patients. Pathological interaction between platelets and cancer cells can be mimicked in co‐culture, and eptifibatide inhibits these pathological interactions, suggesting that eptifibatide is a candidate drug for prevention of ovarian cancer and thrombosis in ovarian cancer patients. The LXR/RXR pathway is a likely mediator of the eptifibatide interference in platelet‐cancer interaction, and represents a candidate target for reducing platelet‐mediated adverse events in ovarian cancer patients.
Tumor Microenvironment Characterization using a Spatial Multiomic Assay to Simultaneously Profile Protein and Gene Expression in FFPE Tumors
Authors: Chew Jennifer , Uytingco Cedric , Anaparthy Naishitha , Chiang Jun , Galonska Christina , Ganapathy Karthik , Hatori Ryo , Hermes Alexander , Katiraee Layla , Katsori Anna‐Maria , Nitsch William , Roelli Patrick , Shuga Joe , Spalinkas Rapolas , Turkekul Mesruh , Veire Benton , Walker Dan , Sheldon Jyoti , Weisenfeld Neil , Williams Stephen , Bent Zachary , Stoeckius Marlon 
Published: May 2022

The tumor microenvironment (TME) is composed of highly heterogeneous structures and cell types that dynamically influence and communicate with each other. The constant interaction between a tumor and its microenvironment plays a critical role in how the cancer develops, progresses, and responds to therapies. Traditionally, Hematoxylin and Eosin (H&E) and immunohistochemistry staining have been used to annotate and characterize tissues and associated pathologies. Recent single analyte approaches spatially interrogate targeted or transcriptome‐wide expression of RNA in tissue sections, while others capture phenotypes using a limited number of protein markers. However, for a more comprehensive understanding of the unique characteristics of cell types, cell states, and cell‐cell interactions within the TME, analysis of multiple analytes is necessary.Here we demonstrate a novel, streamlined multiomic spatial assay that integrates histological staining and imaging with simultaneous transcriptome‐wide gene expression and highly multiplexed protein expression profiling from the same formalin‐fixed paraffin embedded (FFPE) tissue section. In short, tissue sections from archived FFPE samples were placed on slides containing arrayed capture oligos with unique positional barcodes. The H&E stained tissues were then imaged, followed by incubation with transcriptome‐wide probes and a high‐plex DNA‐barcoded antibody panel containing intra‐ and extracellular markers. Transcriptome probes and antibody‐barcodes were then spatially captured on the slide and converted into sequencing‐ready libraries. Our data analysis and interactive visualization software enable interrogation of all data layers (H&E morphology, RNA, protein) from the same tissue section.We apply this method to simultaneously measure gene and protein expression within the TME of human breast cancer and melanoma FFPE samples using whole transcriptome probes and an immune‐oncology antibody panel. The data enables comparison and correlation of multiple analytes and their patterns within the same sample section. In addition, this simultaneous detection enables marker‐guided regional selection and differential gene expression analysis on the defined areas. Taken together, our data demonstrates that a spatially resolved, multiomic approach provides a more comprehensive understanding of cellular behavior in and around tumors, yielding new insights into disease progression, predictive biomarkers, drug response and resistance, and therapeutic development.