bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative study of Single Crystal (SC)-Diamond and 4H-SiC bulk radiation detectors for room temperature alpha spectroscopy
Authors: Mohapatra S. , Abhangi M. , Vala S. , Kumar Sahu P. , Rath S. , Narasimha Murty N.V.L.
Published: June 2021

In this work, the fabrication, electrical characterization
and alpha spectral characterization of single-crystal (SC) diamond
bulk radiation detector have been carried out. The performance
metrics of the SC-diamond bulk detector such as the leakage current
density, charge collection efficiency, spectral resolution and
polarization effects are studied and are compared with a bulk
detector fabricated using High-Pure Semi-Insulating (HPSI)
4H-SiC. It is found that the SC-diamond detector exhibits lower
leakage current density, higher μτ product, better spectral
resolution and no polarization effects in comparison to the HPSI
4H-SiC detector. The time response analysis of the SC-diamond
detector is carried out to study the effect of alpha particles on
the operation of the SC-diamond detector. Accordingly, the stability
of the SC-diamond detector is tested by evaluating the total counts
versus real time and the performance of the diamond detector is
found to be stable during the alpha-time spectroscopy. Hence,
diamond bulk detectors using commercially available electronic grade
diamond may be better suited for alpha particle spectroscopy
compared to HPSI 4H-SiC of nearly equivalent thickness.
Quantifying nitrogen loss hotspots and mitigation potential for individual fields in the US Corn Belt with a metamodeling approach
Authors: Kim Taegon , Jin Zhenong , Smith Timothy M , Liu Licheng , Yang Yufeng , Yang Yi , Peng Bin , Phillips Kathryn , Guan Kaiyu , Hunter Luyi C , Zhou Wang
Published: June 2021

The high productivity in the US Corn Belt is largely enabled by the consumption of millions of tons of manufactured fertilizer. Excessive application of nitrogen (N) fertilizer has been pervasive in this region, and the unrecovered N eventually escaped from croplands in forms of nitrous oxide (N2O) emission and N leaching. Mitigating these negative impacts is hindered by a lack of practical information on where to focus and how much mitigation potential to expect. At a large scale, process-based crop models are the primary tools for predicting variables required by decision making, but their applications are prohibited by expensive computational and data storage costs. To overcome these challenges, we built a series of metamodels to learn the key mechanisms regarding the carbon (C) and N cycle from a well-validated process-based biogeochemical model, ecosys. The trained metamodel captures over 98% of the variability of the ecosys simulated outputs for 99 randomly selected counties in Iowa, Illinois, and Indiana. To identify hotspots with high mitigation potential, we introduce net societal benefit (NSB) as an indicator for synthesizing the loss in yield and social benefits through emissions and pollutants avoided. Our results show that reducing N fertilizer by 10% leads to 9.8% less N2O emissions and 9.6% less N leaching at the cost of 4.9% more SOC depletion and 0.6% yield reduction over the study region. The estimated total annual NSB is $395 M (uncertainty ranges from $114 M to $1271 M), including $334 from social benefits (uncertainty ranges from $46 M to $1076 M), $100 M from saving fertilizer (uncertainty ranges from $13 M to $455 M), and −$40 M due to yield changes (uncertainty ranges from −$261 M to $69 M). For the median scenario, we noted that 20% of the study area accounts for nearly 50% of the NSB, and thus represent hotspot locations for targeted mitigation. Although the uncertainty range suggests that developing such a high-resolution framework is not yet settled and the scenario based estimations are not appropriate to inform the management practices for individual farmers, our efforts shed light on the new generation of analytical tools for life cycle assessment.
Quantitation of Cabozantinib in Human Plasma by LC–MS/MS
Authors: Jones Reyna , Holleran Julianne , Parise Robert A , Rudek Michelle A , Chan Jennifer , Wen Yujia , Gobburu Joga , Lewis Lionel D , Beumer Jan H
Published: June 2021

To support a phase III randomized trial of the multi-targeted tyrosine kinase inhibitor cabozantinib in neuroendocrine tumors, we developed a high-performance liquid chromatography mass spectrometry method to quantitate cabozantinib in 50 μL of human plasma. After acetonitrile protein precipitation, chromatographic separation was achieved with a Phenomenex synergy polar reverse phase (4 μm, 2 × 50 mm) column and a gradient of 0.1% formic acid in acetonitrile and 0.1% formic acid in water over a 5-min run time. Detection was performed on a Quattromicro quadrupole mass spectrometer with electrospray, positive-mode ionization. The assay was linear over the concentration range 50–5000 ng/mL and proved to be accurate (103.4–105.4%) and precise (<5.0%CV). Hemolysis (10% RBC) and use of heparin as anticoagulant did not impact quantitation. Recovery from plasma varied between 103.0–107.7% and matrix effect was −47.5 to −41.3%. Plasma freeze–thaw stability (97.7–104.9%), stability for 3 months at −80°C (103.4–111.4%), and stability for 4 h at room temperature (100.1–104.9%) were all acceptable. Incurred sample reanalysis of (N = 64) passed: 100% samples within 20% difference, −0.7% median difference and 1.1% median absolute difference. External validation showed a bias of less than 1.1%. This assay will help further define the clinical pharmacokinetics of cabozantinib.
Staying-at-Home with Tragedy: Self-expansion Through Narratives Promotes Positive Coping with Identity Threat
Authors: Khoo Guan-Soon , Oh Jeeyun , Nah Soya
Published: June 2021

The COVID-19 pandemic created a historic opportunity to study the link between identity threat and individuals’ temporary expansion of the boundaries of the self (TEBOTS) through stories. Concurrently, the relationship between eudaimonic entertainment processes and self-expansion, particularly feeling moved and self-awareness, was examined. A quasi-experiment was conducted with an online sample (N = 172) that was randomly assigned to watch either a tragic drama or comedy. Results showed that key TEBOTS predictions were largely confirmed for boundary expansion and the outcomes of narrative engagement and entertainment gratifications. Although identity threat was negatively associated with positive coping with the pandemic, this relationship turned positive when mediated by boundary expansion. Further, exposure to tragedy raised feelings of “being moved,” which, in turn, was linked to self-perceptual depth and expanded boundaries of the self downstream. The present findings suggest that self-expansion through story consumption could benefit viewers’ positive reframing of challenging life experiences.
Coordinated pyruvate kinase activity is crucial for metabolic adaptation and cell survival during mitochondrial dysfunction
Authors: Zhou Xiaoshan , Mikaeloff Flora , Curbo Sophie , Zhao Qian , Kuiper Raoul , Végvári Ákos , Neogi Ujjwal , Karlsson Anna
Published: June 2021

Deoxyguanosine kinase (DGUOK) deficiency causes mtDNA depletion and mitochondrial dysfunction. We reported long survival of DGUOK knockout (Dguok−/−) mice despite low (<5%) mtDNA content in liver tissue. However, the molecular mechanisms enabling the extended survival remain unknown. Using transcriptomics, proteomics and metabolomics followed by in vitro assays, we aimed to identify the molecular pathways involved in the extended survival of the Dguok−/− mice. At the early stage, the serine synthesis and folate cycle were activated but declined later. Increased activity of the mitochondrial citric acid cycle (TCA cycle) and the urea cycle and degradation of branched chain amino acids were hallmarks of the extended lifespan in DGUOK deficiency. Furthermore, the increased synthesis of TCA cycle intermediates was supported by coordination of two pyruvate kinase genes, PKLR and PKM, indicating a central coordinating role of pyruvate kinases to support the long-term survival in mitochondrial dysfunction.
Gallstone extraction from a back abscess resulting from spilled gallstones during laparoscopic cholecystectomy: a case report
Authors: Mehmood Saqib , Singh Sohail , Igwe Chukwuemeka , Obasi Chekwas O , Thomas Rhys L
Published: June 2021

Laparoscopic cholecystectomy is a routinely performed surgery nowadays. However, it is associated with certain complications. Gall bladder perforation during the procedure can result in spilled and lost gallstones. Lost gallstones most commonly cause intra-abdominal infection. However, very rarely, they can be associated with troublesome retroperitoneal abscess formation. We present a case where a lost gallstone caused a retroperitoneal abscess formation and was retrieved from a back abscess in the right paraspinal region.
Selection on Phalanx Development in the Evolution of the Bird Wing
Authors: de Bakker Merijn A G , van der Vos Wessel , de Jager Kaylah , Chung Wing Yu , Fowler Donald A , Dondorp Esther , Spiekman Stephan N F , Chew Keng Yih , Xie Bing , Jiménez Rafael , Bickelmann Constanze , Kuratani Shigeru , Blazek Radim , Kondrashov Peter , Renfree Marilyn B , Richardson Michael K
Published: June 2021

The frameshift hypothesis is a widely accepted model of bird wing evolution. This hypothesis postulates a shift in positional values, or molecular-developmental identity, that caused a change in digit phenotype. The hypothesis synthesized developmental and paleontological data on wing digit homology. The “most anterior digit” (MAD) hypothesis presents an alternative view based on changes in transcriptional regulation in the limb. The molecular evidence for both hypotheses is that the MAD expresses Hoxd13 but not Hoxd11 and Hoxd12. This digit I “signature” is thought to characterize all amniotes. Here, we studied Hoxd expression patterns in a phylogenetic sample of 18 amniotes. Instead of a conserved molecular signature in digit I, we find wide variation of Hoxd11, Hoxd12, and Hoxd13 expression in digit I. Patterns of apoptosis, and Sox9 expression, a marker of the phalanx-forming region, suggest that phalanges were lost from wing digit IV because of early arrest of the phalanx-forming region followed by cell death. Finally, we show that multiple amniote lineages lost phalanges with no frameshift. Our findings suggest that the bird wing evolved by targeted loss of phalanges under selection. Consistent with our view, some recent phylogenies based on dinosaur fossils eliminate the need to postulate a frameshift in the first place. We suggest that the phenotype of the Archaeopteryx lithographica wing is also consistent with phalanx loss. More broadly, our results support a gradualist model of evolution based on tinkering with developmental gene expression.
French Grammars
Authors: Abeillé Anne
Published: June 2021

This article focuses on the 20th and 21st centuries, which have seen a growing number of grammars devoted to the French language. Some aim at a scholastic audience, while others aim at a wider public. Some are prescriptive, usually based on literary texts; others are descriptive, incorporating spoken and informal uses; and still others are theoretically oriented, using French as an illustration of the theory advocated. Some are mostly devoted to morphology and syntax while others integrate semantics and discourse. Some include comparisons between French and other languages. Most French grammars started with a terminology inherited from Latin grammars, and both the list of terms and the analyses have evolved thanks to the development of linguistic theories and also to consider colloquial uses and spoken French. Particular points of interest are descriptions of determination (with the category “determiner” appearing only after 1960), negation, the pronominal system, and relative clauses.
Reliability of the AR-CALUX®In Vitro Method Used to Detect Chemicals with (Anti)Androgen Activity: Results of an International Ring Trial
Authors: Milcamps Anne , Liska Roman , Langezaal Ingrid , Casey Warren , Dent Matthew , Odum Jenny
Published: June 2021

The AR-CALUX® in vitro method is a reporter gene-based transactivation method where endocrine active chemicals with androgenic or anti-androgenic potential can be detected. Its primary purpose is for screening chemicals for further prioritization and providing mechanistic (endocrine mode of action) information, as defined by the Organisation of Economic Cooperation and Development (OECD) conceptual framework for the testing and assessment of endocrine-disrupting chemicals. This article describes the conduct and results of an international ring trial with 3 EU-NETVAL laboratories and the test method developer. It was organized by EURL ECVAM to validate the method by testing 46 chemicals. A very good reproducibility within and between laboratories was concluded (94.7–100% and 100% concordance of classification) with low within and between laboratory variability (less than 2.5% CV on EC50 values). Moreover, the variability is within the range of other validated, mechanistically similar methods. In comparison to the AR-reference list compiled by ICCVAM, an almost 100% concordance of classifications was obtained. This method allows the detection of the agonist and antagonist properties of a chemical. A specificity control test was developed during the validation study and added to the antagonist assay rendering the assay more specific. A comparison is made with the mechanistically similar methods AR-EcoScreen™ and 22Rv1/MMTV GR-KO TA. The AR-CALUX® method was approved for inclusion in the recently updated OECD test guideline TG458 which incorporates all 3 methods.
The Effect of Temperature on Disease Severity and Growth ofFusarium oxysporumf. sp.apiiRaces 2 and 4 in Celery
Authors: Kaur Sukhwinder , Barakat Radwan , Kaur Jaskirat , Epstein Lynn
Published: June 2021

Fusarium oxysporum f. sp. apii race 4, which is in F. oxysporum species complex (FOSC) Clade 2, causes a new Fusarium wilt of celery. We compared F. oxysporum f. sp. apii race 4 with race 2, which causes Fusarium yellows of celery and is in FOSC Clade 3. Optimal temperatures for celery yield are 16 to 18°C. Soil temperatures in California celery production areas can range up to 26°C, and the maximal rate of hyphal extension of F. oxysporum f. sp. apii races 2 and 4 in culture are 25 and 28°C, respectively. Here, we compared the effect of temperatures from 16 to 26°C on growth of F. oxysporum f. sp. apii races 4 and 2 in two celery cultivars: Challenger, which is resistant to F. oxysporum f. sp. apii race 2 and susceptible to race 4; and Sonora, which is susceptible to both F. oxysporum f. sp. apii races 2 and 4. Based on linear regressions, as temperature increases, there is an increase in the log of F. oxysporum f. sp. apii race 4 DNA concentration in celery crowns and in the reduction in plant height. Based on logistic regressions, as temperature increases, the incidence of vascular discoloration increases in celery with either F. oxysporum f. sp. apii race 2 or 4 infection. In both cultivars, temperatures of 22°C and above resulted in a significantly (α = 0.05) greater concentration of F. oxysporum f. sp. apii race 4 than race 2 in planta. The concentration of F. oxysporum f. sp. apii race 2 in crowns in ‘Challenger’ is temperature-independent and comparatively low; consequently, ‘Challenger’ is, at least partly, resistant rather than tolerant to F. oxysporum f. sp. apii race 2.
Endosomal lipids in trafficking and signaling
Authors: Gruenberg Jean
Published: June 2021

During endocytosis, cell surface components including housekeeping receptors and activated signaling receptors are delivered to early endosomes, where they are sorted to be either reutilized via recycling pathways or transported towards late endosomes and then lysosomes for degradation. In the latter case, down‐regulated receptors and other molecules destined for the lysosomes are incorporated into lumenal invaginations of the early endosome membrane, which are pinched off as free cargo‐containing vesicles. These multivesicular regions detach and become multivesicular endosomes, which are transported to and fuse with late endosomes. Eventually, intralumenal vesicles (ILVs) and their cargo are delivered to lysosomes and degraded. Alternatively, ILVs can also be released extracellularly as exosomes, upon fusion of multivesicular endosomes with the plasma membrane. Low‐density lipoproteins (LDL) that have been endocytosed are eventually delivered to multivesicular late endosomes. There, cholesteryl esters are deesterified so that free cholesterol can be released and exported to other cellular destinations. The export mechanisms remain ill defined, but it is clear that disruption of the process has profound consequences for cellular sterol homeostasis and can result in the neurodegenerative disease Niemann‐Pick C (NPC). Our previous studies suggest that the fate of LDL‐derived cholesterol is linked to the unconventional phospholipid lysobisphosphatidic acid (LBPA) that is abundant in late endosome intralumenal membranes, since interfering with LBPA functions phenocopies NPC at the cellular level. Our approaches to study the mechanisms of ILV formation and endosomal cholesterol transport will be discussed, including biochemical strategies and unbiased high content image‐based screens.

Support or Funding Information

Swiss National Science Foundation; Swiss National Centre of Competence in Research Chemical Biology; LipidX from the Swiss SystemsX.ch initiative

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Complex interplay of kinetic factors governs the synergistic properties of HIV‐1 entry inhibitors
Authors: Ahn Koree , Root Michael
Published: June 2021

The homotrimeric HIV‐1 envelope glycoprotein (Env) undergoes receptor‐triggered structural changes that mediate viral entry through membrane fusion. This process is inhibited by chemokine receptor antagonists (CoRAs) that block Env–receptor interactions and by fusion inhibitors (FIs) that disrupt Env conformational transitions. Synergy between CoRAs and FIs has been attributed to a CoRA‐dependent decrease in the rate of viral membrane fusion that extends the lifetime of the intermediate state targeted by FIs. Here, we demonstrated that the magnitude of CoRA/FI synergy unexpectedly depends on FI‐binding affinity and the stoichiometry of chemokine receptor binding to trimeric Env. For C‐peptide FIs (clinically represented by enfuvirtide), synergy waned as binding strength decreased until inhibitor combinations behaved additively. Curiously, this affinity dependence on synergy was absent for 5‐Helix‐type FIs. We linked this complex behavior to the CoRA dependence of Env deactivation following FI binding. For both FI classes, reducing chemokine receptor levels on target cells or eliminating competent chemokine receptor‐binding sites on Env trimers resulted in a loss of synergistic activity. These data imply that the stoichiometry required for CoRA/FI synergy exceeds that required for HIV‐1 entry. Our analysis suggests two distinct roles for chemokine receptor binding, one to trigger formation of the FI‐sensitive intermediate state and another to facilitate subsequent conformational transitions. Together, our results could explain the wide variety of previously reported activities for CoRA/FI combinations. These findings also have implications for the combined use of CoRAs and FIs in antiviral therapies and point to a multifaceted role for chemokine receptor binding in promoting HIV‐1 entry.

Support or Funding Information

R01 GM066682 to MJR

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Six2 regulates palate development by inhibiting palatal bone formation during development
Authors: Sweat Yan Yan , Sweat Mason , Mansaray Maurisa , Saadi Irfan , Lachke Salil , Butali Azeez , Amendt Brad
Published: June 2021

Cleft lip with or without cleft palate (CL/P) is the most common congenital craniofacial defect, with a frequency of 1 in 500 to 1 in 2500 live births depending on the population, and lifelong care can cost more than $100,000. In mice, secondary palate development occurs from E11.5 to E17.5, and consists of outgrowth, elevation, extension and fusion processes. At any stage during palatogenesis, the disruption of these processes could cause cleft palate, and these processes are all regulated in part by palatal mesenchyme.

Objective

To examine Six2, a transcription factor previously shown to play a role in craniofacial and kidney development, for a role in clefting predicted by the SYSFACE tool.

Methods

Six2 knockout mice were generated and examined for clefting at different embryonic stages and P0 and craniofacial developmental defects.

Results

We demonstrate that ablation of Six2 contributes to palatogenesis. We have characterized the clefting phenotype in Six2−/− embryos, demonstrating that the palate shelves fail to extend to the midline and contain premature ossified tissue compared to wild‐type (WT) littermates. The expression of Runx2 and its target Osx were higher in Six2−/− palates and surrounding maxilla with cleft than in control littermates. Histochemistry and immunohistochemistry experiments demonstrate premature ossification by specific cells in the Six2−/− palate.

Conclusions

Six2 is a regulator of palate development and it acts by negatively regulating the ossification of palatal mesenchyme. In Six2−/− mice, ectopic ossification prevents the extension of the palate shelves causing cleft.

Support or Funding Information

The University of Iowa, College of Dentistry

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Course Evaluations ‐ Are We Gaining Insight, or Feeding Egos? Using Novel Evaluations to Uncover Value
Authors: Brewer‐Deluce Danielle , Palombella Andrew , Rockarts Jasmine , Wainman Bruce C.
Published: June 2021

Assessment is generally the evaluation of student learning and competency. But, when the roles are reversed, and we ask students for their perspective, assessment has the potential to improve a course. Unfortunately in practice however, there are some limitations. In particular, asking students to rate their experience on ubiquitous Likert scale evaluations imposes a ceiling effect, which limits utility. So while top notch evaluations feel great, and often support tenure, promotion and hiring decisions, constructive change seldom results.

Over the past 7 years the Education Program in Anatomy at McMaster University has focussed on understanding learner profiles in an interprofessional education (IPE)/anatomy dissection course using multiple evaluation strategies. By employing Likert‐scales, qualitative ratings and Q method, students were asked about what they valued in the course. Specifically through Q method's factor analysis, individuals were grouped based on similarities in their rankings of common preferences/viewpoints: three previously unknown independent learner groups (Anatomy IPE Enthusiasts, Practical IPE Advocates and Skeptical IPE Anatomists) were identified for which common challenges could be addressed. Conversely, qualitative and Likert‐based analyses provided less granular information which was not directly useful for course evolution.

With the above study serving as an exemplary template, we will challenge value of current course evaluation practices, and further explore Q methodology as a viable and valuable alternative. In all, session attendees can expect to learn methods for better understanding the types of students in our classrooms which will support strategies for more refined student‐centred learning.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Growth Factor Expression by Cardiac Tissues in the Leopard Gecko (Eublepharis macularius)
Authors: Jacyniak Kathy , Vickaryous Matthew Kenneth
Published: June 2021

Tissue homeostasis is a dynamic process involved in the maintenance of tissue structure and function in response to physiological fluctuations in biochemistry, metabolism, and physical conditions. Despite the profound role that growth factors play in homeostasis of organs such as the heart, constitutive patterns of expression are only known for a handful of species. Here, we investigated growth factor expression in the heart of a representative reptile, the leopard gecko (Eublepharis macularius; hereafter, ‘gecko’). We focused our investigation on three major classes known to be expressed by mammalian cardiac tissues: transforming growth factor β (TGFβ); vascular endothelial growth factor A (VEGF); and basic fibroblast growth factor (FGF‐2). Similar to other squamates (snakes and lizards), geckos have a three‐chambered heart with two atria and one ventricle. The ventricular myocardium includes a trabeculated or spongy‐like inner compartment, and a thin, compact cortical layer. We determined that cardiac cells in both compartments of the gecko myocardium (trabeculated and compact) constitutively express a diverse panel of growth factor ligands and receptors commonly associated with wound healing and repair, including: TGFβ1, activin‐βA, and phosphorylated SMAD2; FGF‐2; and VEGF, VEGF receptor 1 (VEFGR1), VEGFR2, and phosphorylated VEGFR2. Using double immunofluorescence, we observed co‐localization of VEGF/VEGFR2 and VEGFR1/VEGFR2, indicating that – similar to mammals – reptilian cardiomyocytes may use paracrine and autocrine signalling. Taken together, these findings indicate a homeostatic role for these growth factors in the heart that is conserved across reptiles and mammals.

Support or Funding Information

Natural Sciences and Engineering Research Council (NSERC) Discovery Grant 400358 (to MV); Ontario Veterinary College Scholarship (to KJ)

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Sex‐specific Conditions Affecting Vascular Tone, Cerebral Blood Flow and Cognition
Authors: Barnes Jill N.
Published: June 2021

There are sex and sex‐hormone specific differences in autonomic nervous system control of blood pressure. The sympathetic nerve fibers of the autonomic nervous system innervate skeletal muscle blood vessels, initiating vasoconstriction, and thus regulate blood flow and vascular tone. This regulation of vascular tone is different between men and women, such that estrogen increases the activity of the b2‐adrenergic receptor activity (causing vasodilation) which offset sympathetically‐mediated vasoconstriction and results in lower blood pressure values in young women. Higher sympathetic nerve activity is associated with greater augmented aortic blood pressure in young men, but lower augmented aortic blood pressure in young women. Such differences in blood pressure regulation will likely have effects that extend beyond blood pressure, affecting blood flow, and ultimately tissue structure and function. For example, higher aortic blood pressure and greater arterial stiffness of the central arteries are associated with white matter hyperintensity fraction in normotensive postmenopausal women and older adults. In addition, there are conditions unique to women, menopause and pregnancy, that further affect blood pressure and blood flow regulation. Pregnancy constitutes a stress that challenges the regulation of blood pressure and blood flow in women. Hypertensive conditions of pregnancy, such as preeclampsia, carry life‐long risk for developing cardiovascular and cerebrovascular diseases. We evaluated the influence of pregnancy history in postmenopausal women on vascular function, cerebral blood flow, and cognition 35 years after pregnancy. Aortic blood pressure was associated with lower cognitive function scores in women with a history of preeclampsia. Additionally, women with a history of preeclampsia had lower cerebral blood flow responses to a vasodilatory stimulus and this was associated with greater intravascular cellular activation. Furthermore, women with a history of preeclampsia and with late‐life hypertension had atrophy in specific regions of the brain, suggesting that pregnancy history may later impact brain structure. Therefore, conditions that a woman may experience during pregnancy may be informative for future risk of disease. In summary, understanding sex‐specific physiological mechanisms, and how this may change over the lifespan is crucial for identification and treatment of individuals at accelerated risk of cardiovascular and cerebrovascular disease.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Sex Differences in Remodeling of the Failing Heart
Authors: Kararigas Georgios
Published: June 2021

Heart failure (HF) is a leading cause of hospitalization and death and can be characterized by either reduced or preserved ejection fraction. Cardiomyopathies like Takotsubo and HF manifest differently between men and women. More men have maladaptive remodeling underlain by higher induction of pro‐fibrotic pathways, while women repress inflammatory pathways. Sex and menopause‐related differences in the incidence and the prognosis of cardiovascular disease have pointed to the sex hormone 17β‐estradiol (E2) and its receptors (ER α and β). Employing the transverse aortic constriction model in mice to study E2‐ and sex‐specific regulation of pressure overload‐induced left ventricular hypertrophy and HF, the E2/ER axis is considered cardioprotective in females. In contrast, E2 exerts deleterious effects in male hearts and cardiac cells. Detailed characterization of the regulation of cardiac (patho)physiology by sex and E2 and elucidation of the underlying mechanisms may lead to the identification of novel therapeutic targets, which may have a wide implication in the development of new and personalized therapies.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Stem Cell Biology of Airway Submucosal Glands during Development and Disease
Authors: Engelhardt John F.
Published: June 2021

Lineage‐tracing studies in the mouse lung suggest that multiple region‐specific progenitors contribute to regenerative plasticity of the airway epithelium. Airway submucosal glands (SMGs) are thought to house stem cell niches for the surface airway epithelium; however, the phenotype of the SMG‐derived progenitor cells remains unclear. SMGs are tubuloacinar structures embedded within the mesenchyme beneath the surface of all cartilaginous airways in humans and the proximal trachea of mice. These structures secrete important factors that regulate airway clearance and maintain sterility at homeostasis and in response to injury and infection. Secretory functions of SMGs are severely affected in cystic fibrosis, a genetic disease caused by mutation in the cystic fibrosis transmembrane conductance regulator, and disease‐associated alterations in neuropeptide (CGRP) expression alter the slowly cycling stem cell niches of SMGs. In this context, CGRP acts as both a secretagogue to stimulate gland secretion following injury—a response defected in cystic fibrosis—and a mitogen of glandular progenitor cells. To better define the contribution of SMG stem cells in airway regeneration and abnormalities to these processes in cystic fibrosis, we have dissected Wnt‐regulated mechanism that control both the formation of glandular stem cell niches during development and lineage‐commitment of glandular stem cells during airway regenerative responses following injury. Using lineage tracing in mice, we demonstrate that multipotent glandular myoepithelial cells form very early during SMG development in a Wnt/TCF‐dependent manner. In the adult mouse trachea, SMG myoepithelial cells can give rise to seven cell types in the proximal airway following severe injury. Similar to the stem cell program adopted during SMG development, Wnt/TCF signals appear to control self‐renewal and lineage commitment of glandular myoepithelial stem cells following injury. These studies clarify important stem cell targets for therapy in the cystic fibrosis lung.

Support or Funding Information

NIDDK

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Myofascial Pathologies, Their Treatment, and the Importance of Patient Education
Authors: Schabacker Kara
Published: June 2021

The importance of healthcare provider understanding and patient education in the foundational principles governing the fascia of the human body cannot be overstated. What the fascia is, what it does, and what purpose it serves (i.e., What's the point of this vast structural framework?) versus what patients usually “think” is going on in their bodies are often vastly different. There exists a myriad of fascial pathologies in which the fascia goes awry and results in people ending up on the clinical massage therapy table. These include long term and chronic physical issues, short term injuries, and even emotional stress. There are techniques through which the fascia can be manipulated and released to alleviate the physical, emotional, and mental stressors and the patterns behind them. This presentation will elaborate on exactly how the fascial system stores, processes, and (with intervention) releases these holding patterns either with self care or the help of a licensed massage therapist. It will include vignettes from the clinician perspective including humans of all life stages and activity levels (from infant to elderly, from sedentary to professional athlete) and other animal models such as dogs and horses. The emphasis of this presentation will be on the practical and real‐world application of interventions focused on fascia and it's roles in both containment and communication within the body.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Precisely heterogeneous ‐ the making of N‐glycoproteins
Authors: Aebi Markus
Published: June 2021

Two dedicated organelles, the Endoplasmic Reticulum (ER) and the Golgi contain the synthetic machinery that generates N‐linked glycans, the most divers modification of proteins. The ER pathway generates a structurally highly conserved oligosaccharide that is transferred to selected asparagine residues of nascent polypeptide chains. These oligosaccharides are essential for the folding and the quality control process of glycoproteins. The subsequent trimming and remodeling of N‐linked glycans in the Golgi compartment follows a completely different regime and generates a heterogeneous assembly of N‐glycans in a species‐, protein‐ and site‐specific manner.

We have established MS‐based analytical systems for the site‐specific quantification of N‐linked glycans and combined it with expression systems of model glycoproteins (such as IgG) in different cell lines. We quantified the site‐specific glyco‐heterogeneity and showed that the interaction of the glycan with the protein surface defined the processing in a given setting of hydrolases and glycosyltransferases. We hypothesized that this site‐dependent processing requires a kinetic control of glycan remodeling in the Golgi, which, in turn, is the cause for the well‐known microheterogeneity of N‐glycans.

We have experimentally addressed this concept of glycan processing and followed the time‐course of intracellular N‐glycan processing in vivo using time‐resolved SILAC experiments. In addition, we assessed site‐specific N‐glycan processing in vitro using purified glycosyltransferases and hydrolases. We conclude that the compartmentalization of glycosyltransferases and hydrolases in the different Golgi stacks is a prerequisite for site‐specific N‐glycan processing. The lamellar structures of the Golgi cisternae is necessary to provide the high concentration of processing enzymes that can act only for a short time on secreted substrates.

Support or Funding Information

Supported by the Swiss National Science Foundation and ETH Zurich

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Mapping the O‐GlcNAc‐Cytoprotective network
Authors: Zachara Natasha , Groves Jennifer , Guo Chenxu , Martinez Marissa , Fahie Kamau , McKen Cathrine , Maduka Austin , O'Meally Robert , Cole Robert
Published: June 2021

In the 30 years since the discovery of nucleocytoplasmic glycosylation, O‐GlcNAc has been demonstrated to regulate protein function by modulating characteristics that include protein folding, localization, degradation, activity, post‐translational modifications, and interactions. The cell coordinates these molecular events, on thousands of cellular proteins, in concert with environmental and physiological cues to fine‐tune epigenetics, transcription, translation, signal transduction, the cell cycle, and metabolism. The cellular stress response is no exception: diverse forms of injury result in dynamic changes to the O‐GlcNAc sub‐proteome that promote survival. To date, the majority of studies have focused on identifying proteins and pathways regulated by O‐GlcNAc that combat cytotoxicity. Currently, little is known about the regulation of the two enzymes that write and erase the O‐GlcNAc‐modification, the O‐GlcNAc transferase (OGT) and the O‐GlcNAcase (OGA). To provide insight into the regulation of OGA, the enzyme that catalyzes the removal of O‐GlcNAc, proximity biotin ligation (BioID) in combination with Stable Isoptope Labeling of Amino Acids in Cell Culture (SILAC) was used to define the basal and stress‐induced interactome of OGA. This analysis revealed 90 interaction partners of OGA, many of which exhibited increased binding to OGA upon stress. The associations of OGA with fatty acid synthase, OGT, heat shock cognate 70 kDa protein (HSC70), filamin‐A, and heat shock protein 27 (HSP27) were confirmed by co‐immuno‐precipitation. Furthermore, the pool of OGA bound to FAS demonstrated a substantial reduction in specific activity (~85%), suggesting that FAS is a novel protein inhibitor of OGA. Consistent with these observations, overexpression of FAS augmented O‐GlcNAcylation of a subset of cellular proteins. Collectively, these data support a model in which protein interactors of OGA, such as FAS, regulate its local activity and thus lead to remodeling of the O‐GlcNAc‐sub proteome in a manner consistent with cell survival.

Support or Funding Information

This work was supported by grants from the NIH National Heart, Lung, and Blood Institute (P01HL107153), the NIH National Institute on Aging (F31AG047724), and the NIH National Institute of General Medical Sciences (MARC U‐STAR; T34GM008663). Core Facility support was provided NIH Grant S10 RR024550 ‐ Research Resources (JHUSOM Microscope Facility) and NIH Grant 2P30 CA006973 ‐ National Cancer Institute (JHUSOM Mass Spectrometry and Proteomics Facility).

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Corralling Pancreatic Cancer through Epigenetic Reprogramming
Authors: Evans Ronald M. , Antal C. , Truitt M. , Liang G. , Sherman M. , O'Dwyer P. , Drebin J. , Downes M. , Tuveson D.
Published: June 2021

Pancreatic ductal adenocarcinoma (PDAC) occurs in the context of an exuberant desmoplastic response that produces a ‘living chimera’ of tumor and activated stromal components. We have shown that the vitamin D receptor (VDR) is expressed at high levels in activated human pancreatic stellate cells (PSCs) and, in response to ligand, reprograms PSCs to the quiescent state. In vivo, a synthetic VDR agonist (Cal) similarly remodels tumor stroma, enhancing the anti‐tumor effects of gemcitabine and reducing tumor growth.

We will describe the use of a three‐dimensional culture system to dissect the adaptive impact of the stromal secretome on the cancer cell. This integrative approach identified the rapid mobilization of more than a dozen gene networks (cell cycle, steroid biosynthesis, metabolic pathways, DNA replication, etc.), as well as a commensurate adaptive metabolome.

In examining chromatin adaptation, our work uncovers a molecular ‘and‐gate’ such that tumor activation is the consequence of mutant Ras and the TME. To mediate this molecular handshake, we find that BRD2 (but not BRD4) in the epithelial compartment transduces stromal cues at the genomic level. This response is blocked by the BET bromodomain inhibitor JQ1 and reduces pancreatic tumor growth in vivo. Collectively, we describe a novel molecular connection between the stroma and a driver oncogene that offers new insights into the role of the TME in the treatment of ras‐driven tumor.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Metabolism, Inflammation, and Tumor Progression
Authors: Simon M. Celeste
Published: June 2021

Altered tumor cell metabolism is now firmly established as a hallmark of human cancer. Downstream of oncogenic events, metabolism is re‐wired to support cellular energetics and supply the building blocks for biomass. Rapid, uncontrolled proliferation results in tumor growth beyond the reach of existing vasculature and triggers cellular adaptations to overcome limiting nutrient and oxygen delivery. However, oncogenic activation and metabolic re‐programming also elicit cell intrinsic stresses, independent of the tumor microenvironment. To ensure metabolic robustness and stress resistance, pro‐growth signals downstream of oncogene activation or tumor suppressor loss simultaneously activate homeostatic processes. Here, I will summarize adaptive mechanisms co‐opted by common oncogenes, including mTOR, MYC, and RAS. Recurrent themes include: (1) coordination of oncogene‐induced changes in protein and lipid metabolism to sustain endoplasmic reticulum homeostasis, (2) maintenance of mitochondrial functional capacity to support anabolic metabolism, (3) adaptations to sustain intracellular metabolite concentrations required for growth, and (4) prevention of oxidative stress. Ultimately, an understanding of the adaptations required by both tumor cells and recruited inflammatory cells could reveal targetable metabolic vulnerabilities.

Support or Funding Information

R35 CA197602 (Outstanding Investigator Award)Title: “Metabolic Tumor Suppressors in Renal Cancer: Unprecedented Roles in Disease Progression”3 P01 CA 104838Title: “Cancer Cell Adaptation to Metabolic Stress”

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Dynamic mechanisms of Xist RNA localization in female lymphocytes: a new form of X‐chromosome Inactivation maintenance
Authors: Anguera Montserrat C. , Syrett Camille
Published: June 2021

Females mount stronger immune responses and clear pathogens faster than males, yet they are more susceptible to autoimmune and inflammatory disorders. One important biological factor underlying this sex bias is the X‐chromosome, which is enriched for immunity‐related genes. Female mammals use X‐Chromosome Inactivation (XCI) to generate a transcriptionally silent inactive X‐chromosome enriched with heterochromatic modifications and the long noncoding RNA Xist, which equalizes gene expression between the sexes. We have discovered that XCI is maintained differently in female lymphocytes from mice and humans, where Xist RNA and heterochromatic modifications dynamically associate with the inactive X‐chromosome. Mature naïve B cells are missing Xist RNA and heterochromatin marks on the inactive X, and these marks return to most cells with in vitro stimulation. We found that the chromatin of the inactive X changes during early B cell commitment, at the pro‐B cell stage, initiated by the loss of Xist RNA localization. In mature lymphocytes, we found evidence of biallelic expression and increased dosage of immunity‐related X‐linked genes including TLR7 and CXCR3, in support of relaxed transcriptional silence from the inactive X. During B cell activation, Xist RNA is relocalized to the inactive X by the transcription factor YY1, in a novel two‐step process unique to B cells. YY1‐mediated relocalization of Xist RNA during B cell stimulation is necessary for enrichment of heterochromatin modifications and maintenance of X‐linked gene silencing. Furthermore, we examined lymphocytes from patients with systemic lupus erythematosus, an autoimmune disorder with a strong female bias, and observed mislocalized XIST RNA transcripts and evidence of biallelic expression of immunity‐related genes from both X‐chromosomes. We propose that the Xi in female lymphocytes is predisposed to become partially reactivated and to overexpress immunity‐related genes, providing the first mechanistic evidence for the female‐specific enhanced immune responses and increased susceptibility for autoimmunity.

Support or Funding Information

R21 AI124084

5K12 HD085848‐03

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Aging photoreceptors: light, stress and transcription
Authors: Weake Vikki M.
Published: June 2021

Aging is associated with functional decline of neurons and increased incidence of both neurodegenerative and ocular disease. Photoreceptor neurons in Drosophila melanogaster provide a powerful model for studying the molecular changes involved in functional senescence of neurons since decreased visual behavior precedes retinal degeneration. Flies show decreased phototaxis by day 40 without any significant retinal degeneration. We have identified gene expression changes that correlate with this functional decline in visual behavior during aging. By profiling the nuclear transcriptome of genetically‐labeled photoreceptors over a 40 day time course, we identified increased expression of genes involved in stress and DNA damage response, and decreased expression of genes required for neuronal function. These age‐regulated genes share specific sequence motifs and genomic features suggesting that both transcription factors and epigenetic mechanisms contribute to these expression changes. In addition, we have identified age‐regulated splicing events in photoreceptors, and shown that these differentially spliced genes are enriched for visual function and phototransduction. Indeed, proper splicing is necessary for visual behavior in young flies because photoreceptor‐specific RNAi against multiple splicing factors reduces phototaxis. To identify the environmental factors that drive the age‐related changes in gene expression and splicing, we have developed a blue light stress model that induces oxidative stress and eventual retinal degeneration. Using this light stress model, we have shown that there is a strong correlation between the gene expression changes in photoreceptors that are induced by light and during aging. However, there are also some significant differences suggesting that there are other factors that are involved in the age‐related gene expression changes. Current research focuses on identifying the transcription factors and epigenetic regulators that contribute to age‐related changes in gene expression and visual behavior.

Support or Funding Information

The authors thank the Ralph W. and Grace M. Showalter Research Trust, National Institutes of Health R01EY024905 to VW, Purdue University Center for Cancer Research (American Cancer Society Institutional Research Grant, IRG #58‐006‐53; NIH P30 CA023168), and shared Instrumentation Grant, NCRR 1 S10 RR023734‐01A1 for funding to support this work.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.