bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Comparison of Epinephrine, Esmolol, and the Combination of Both in Reperfusion Injury After Murine Myocardial Ischemia
Authors: Blaskowsky Justin , Eckle Tobias 
Published: June 2021

Current research suggests that epinephrine, when used during cardiac arrest, pulseless electrical activity, or ventricular fibrillation, may contribute to reperfusion injury. Esmolol, a short acting cardioselective beta‐blocker, has recently been shown to help mitigate this effect. The objective of this study is to demonstrate the possible cardio‐protective effects esmolol has on murine myocardium. The study was done using 24 C57/BL6 six‐month‐old mice randomized into four experimental groups. Ischemia was induced using the hanging weight system described by Eckle et. al. The mice were exposed to ischemia for one hour and subsequently reperfused with either saline, epinephrine, esmolol, or a combination of epinephrine and esmolol for two hours. After the reperfusion period, blood was drawn to measure troponin levels, and staining with Evans Blue (EB) was performed on the murine hearts. Sectioning and subsequent staining with triphenyltetrazolium chloride (TTC) was done to provide contrast against the EB stain. Infarct size was defined as the ratio of ischemic viable versus non‐viable tissue. The infarct size for each heart was calculated with ImageJ, and later MATLAB was used to provide an automated analysis of infarct area. A full murine heart model was then generated using MATLAB to visually demonstrate differences in infarct size.Preliminary results have indicated a statistically significant reduction of infarct size in the esmolol group when compared to epinephrine, and ongoing analysis shows similar results. The future goals of this study are to provide additional evidence of esmolol as a cardio‐protective drug, and to demonstrate a simple computerized way to identify myocardial infarct area in an animal model.Support or Funding InformationResearch was supported through the University of Colorado Anschutz Medical Campus and the Master of Science in Modern Human Anatomy Program.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Midline Episiotomy May Pose Less Risk of Nerve Damage Than Mediolateral Episiotomy: A Cadaveric Anatomical Study
Authors: Patel Akash , Hung Jun , Castro Monica , Plochocki Jeffrey H. , Hall Margaret I. 
Published: June 2021

Episiotomy, the surgical incision of the perineum to assist during vaginal delivery, can be classified into two main approaches, midline and mediolateral. While use of surgical episiotomies is in a decline, clinicians throughout the world continue to commonly utilize episiotomy. However, current literature provides insufficient anatomic evidence as to which of the two approaches is preferable. Many clinicians utilize a mediolateral approach, arguing that this incision ensures the safety of the external anal sphincter and therefore will not endanger maternal fecal continence postpartum. Other clinicians prefer a midline approach, arguing that incising the perineal body will endanger fewer anatomical structures. In this study, we utilize human cadaveric dissection to identify and understand which anatomical structures are damaged through the use of the two episiotomy approaches to justify a preferential episiotomy procedure. We performed a midline and one of four mediolateral episiotomy incisions using blunt scissors on 15 female cadavers used for medical education at Midwestern University. The posterior minor labia in the midline provided a zero‐degree axis from which angles of incision were calculated to either 60, 45, 30, or 20 degrees from midline using digital calipers and a protractor. After incision, dissection revealed structure damage. All dissections revealed that mediolateral episiotomy damaged the ipsilateral bulb of the vestibule and the overlying bulbospongiosus muscle. The superficial perineal nerve was damaged in 20% of the cadavers, and the anterior labial nerve was damaged in 13% of the cadavers. However, we suspect that during birth when the region is engorged with blood and the vaginal orifice pulled inferiorly and anteriorly, mediolateral episiotomy could result in nerve damage more often than in cadaveric dissection. Based on these results, we suggest that a midline approach might be preferable. Possible denervation to perineal structure may outweigh the potential risks to the external anal sphincter, which would likely heal within weeks postpartum with its nerve supply intact.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Characterization of the roles of connexin 32 in zebrafish vascular development
Authors: Chen Yi‐Ting 
Published: June 2021

The process of vascular development in vertebrates are mainly divided into vasculogenesis and angiogenesis. We previously identified the transcription factors Islet2 (isl2) and Nr2f1b required for the growth of intersegmental vessels (ISV) and caudal vein plexus (CVP) in zebrafish. Microarray analysis showed Connexin 32 is regulated by Isl2/Nr2f1b. Gap junction protein Connexins32 (Cx32) has been shown functions on the blood vessels in injury mice and enhances angiogenesis in cell‐based study, however, there is no reference on the vascular development in animal study. In addition, signal pathways related to cx32 and angiogenesis have not yet been clarified. In this study, we first showed cx32 mRNA is expressed is expressed in developing vessels from 18S to 30 hpf stages, suggesting its roles in vasculature. Knockdown of cx32 by morpholino injection causes vascular defects in ISV and CVP, suggesting the role of cx32 in vascular growth. TUNEL assay showed that vascular defects do not caused by cell death, but likely due to the impairment of endothelial cell proliferation and migration. Consistent with vascular growth defects, loss of cx32 affects the expression of the vascular markers flt4, mrc1, flk, stabilin, and ephrinb2. Furthermore, the overexpression of cx32 does not impair the vascular growth, but rescue the cx32 morphant, suggesting the specificity of morpholino knockdown. Finally, we examine the interaction between cx32 and multiple signals and observed that cx32 is regulated by VEGF signals for ISV growth and BMP signals for CVP patterning.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Using Electric Cell‐substrate Impedance Sensing (ECIS) Technology as a Tool for Mathematical Analysis of the Effects of Glucose on Bone‐like Osteosarcoma Cells (UMR 106‐01 BSP)
Authors: Choi Jeannie , Hernandez Bryan , Joseph Eugene 
Published: June 2021

Mathematical modeling has been useful in studies of the progression of type II diabetes. However, not many studies have been done using electric cell‐substrate impedance sensing (ECIS) technology to validate mathematical modeling in bone cells exposed to high concentrations of glucose. In this study we hypothesized that ECIS technology can be used as a predictive tool to evaluate the effects of glucose on cell membrane impedance in UMR cell cultures by mathematical analysis through predictive mathematical modeling. Briefly, UMR cells were plated at 2.5 × 105 cells/mL in eight‐well (8W) ECIS array plates. Designated wells were treated with different concentrations of glucose (10, 5, and 3 mM). Cell cultures were incubated in a humidified chamber at 37° C with infusion of 5% CO2. Membrane resistance, time of attachment and rate of spreading of the cells were monitored and measured in vitro, using the ECIS machine. Based on the data generated by the ECIS machine, a mathematical formula was derived to predict the resistance of the UMR cell membrane for any concentration of glucose used. The formula was tested based on the generated data. F test ANOVA was employed to compare variances between all experimental trials; all values in the results are expressed as means ±SD. The results show that the highest concentration of glucose caused a decreased time of attachment, rate of spreading and an increased cell membrane resistance in the UMR cells. The following formulas were derived based on the ECIS data: dR/dt=kR0ekt and R[G]=R0e+sG (where dR/dt=rate of spreading, k=rate constant, R0=initial resistance, t=time, [G]=glucose concentration, and s=rate constant (1/[glucose]). The formulas were found to be of predictive value. The results suggest that the ECIS technology is a potentially useful tool in the mathematical analysis of physiological phenomena in bone‐like cells in vitro.Support or Funding InformationThis work was supported by the Ryckman Endowment Student Research Fund of the Biology Department at La Sierra University in Riverside, CA.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Calcium and lipid exchange machinery in Sertoli cells
Authors: Adams Arlo , Yoo David , Vogl A. Wayne 
Published: June 2021

Sperm production (spermatogenesis) takes place in the seminiferous tubules of the testis. Specialized junction complexes termed ‘ectoplasmic specializations' (ESs) in the seminiferous epithelium have several key functions. ESs between Sertoli cells disassemble during the movement of early spermatogenic cells towards the apex of the epithelium and those ESs between a Sertoli cell and late stage spermatids disassemble during sperm release. There is evidence that structures called ‘Tubulobulbar Complexes' (TBCs) are endocytic structures responsible for the internalization and eventual degradation of junctions associated with ESs, allowing for early spermatocyte translocation from the basal epithelium and release of late spermatids from the apical epithelium. One key feature of both ESs and TBCs is their extensive association with peripheral ER. ESs are tripartite in structure consisting of Sertoli cell plasma membrane (PM), a layer of actin bundles, and an overlying leaflet of ER. TBCs are double membrane invaginations that appear as ESs are beginning to break down. They are long, endocytic in‐growths, with a swelled bulb region that contains an extensive ER‐PM contact site. TBC bulbs eventually ‘bud’, fuse, and become endosomes. Little is understood about the function of the ER at both ESs and TBCs, though it is well established that ER contact sites in other cells function in both calcium signalling and lipid exchange. If ER in ESs and ER‐TBC contacts function in calcium and lipid exchange, then known calcium signalling machinery and lipid exchange proteins should be localized to these structures. Using confocal imaging, we localized the CACNA1H voltage gated calcium channel to the PM of apical ESs, and the VAPA integral ER protein, which is associated with lipid synthesis and exchange machinery, to the apical ER as well as the ER in basal regions known to contain ESs. This data adds further weight to the hypothesis that calcium exchange is integral to regulation of ES and TBC structure, as well as begins our exploration into the possible role of lipid exchange at these sites.Support or Funding InformationThis work was supported by the Natural Sciences and Engineering Research Council (NSERC) of Canada (155397‐2013 to A. Wayne Vogl)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Upregulation Of Eicosanoid Signalling In Lung Following Fipronil And Endotoxin Interaction
Authors: Sethi Ram Saran , Pandit Arif Ahmad , Gandham Ravi Kumar , Verma Ramneek , Singh Baljit 
Published: June 2021

It is estimated that nearly 1.8 billion people worldwide use pesticides to minimize the crop damage in efforts to increase food production to feed the growing world population. Exposures to lower concentartion of various pesticides such as fipronil and phenylpyrazole can result in fatal poisonings as well as airway inflammation. Inhalation of endotoxins, which are frequently present in the agricultural buildings, also induces lung inflammation. Animals exposed to both fipronil and endotoxin may demonstrate enhanced lung inflammation. There, however, are limited data available on the molecular mechanisms underlying the toxicity induced by fipronil alone or in combination with endotoxin. Hence, we employed a comprehensive microarray approach in a mouse model to identify the molecular mechanism involved in the lung inflammation by exposing the mice to fipronil (1/20th of LD50/d orally for 90 d) followed by intranasal E. coli LPS (80μg/mouse) or normal saline (N=10 each). Fipronil with or without LPS significantly (p<0.05) increased the total histopathological score suggesting lung damage. Ingenuity Pathway Analysis (IPA) software analysis predicted eicosanoid signalling among the top 5 canonical pathways involved in airway inflammation. Eicosanoid signalling plays important role in pulmonary inflammation and immune response via cytokine production, cell proliferation, antibody formation and antigen presentation. Fipronil alone caused 3‐fold increase in Phospholipase A2G5 (PLA2G5), which hydrolyses the membrane phospholipids to generate various eicosanoids. PLA2G5 showed 1.63 and 4.34 fold increase following exposure to endotoxin alone or in combination with fipronil, respectively. RT‐qPCR and immunohistochemistry analysis validated the microarray data for the PLA2G5. The data taken together indicate up‐regulation of functionally relevant PLA2G5 during fipronil or/and endotoxin induced lung inflammation, which may also play a role in lung inflammation associated with fipronil exposure.Support or Funding InformationGADVASU, LudhianaThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Non‐Canonical DNA in the c‐Myc Hotspot Region
Authors: Long Kimberly , Kerwin Sean M. , David Wendi 
Published: June 2021

G‐quadruplexes and H‐DNA are non‐canonical or non‐B form DNA structures. G‐quadruplexes are three dimensional structures formed by planar stacking of guanine quartets in the DNA. H‐DNA structures form at inverted repeats consisting of poly(purine)•poly(pyrimidine) sequences, in which the poly(purine) portion of one half of the repeat forms a Pu•Py‐Pu triplex by binding to the duplex form of the other half. Genetic “hotspots” are regions of DNA that are especially susceptible to double strand breaks. It has been shown that the structural conformation of DNA could be the cause for some of these breaks in “hotspot” regions. In particular, the well‐known transpositions involving the c‐Myc oncogene in Burkitt Lymphoma involves a “hotspot” region of the gene that is proposed to form two non‐canonical structures, a G‐quadruplex and H‐DNA structure, which are in competition which each other.Surface plasmon resonance (SPR) was used to detect H‐DNA or G‐quadruplex DNA formation in c‐MYC. An immobilized single‐stranded DNA construct encompassing the c‐MYC hotspot region was probed with short oligonucleotides complementary to different regions of the putative H‐DNA and G‐quadruplex DNA structures. These studies demonstrated that both the duplex portion of the putative H‐DNA as well as the poly(purine) track displayed limited hydridization to complement probes, commensurate with formation of an H‐DNA structure.Spectroscopic methods such as UV/vis melting, Förster resonance energy transfer (FRET), and circular dichroism (CD) have been used in previous studies to detect and characterize G‐quaduplexes. Using these spectroscopic methods, we were able to characterize the formation of non‐canonical DNA structure from an oligonucleotide comprised of the entire poly(purine) tract from the c‐MYC hotspot. These studies demonstrate that this poly(purine) sequence adopts a stable intermolecular G‐quadruplex in preference to the intramolecular G‐qaudruplex predicted earlier. This means that the H‐DNA in c‐MYC is likely not in competition for formation with the intramolecular G‐quadruplex suspected to form from this same region.Support or Funding InformationCancer Prevention and Research Institute of TexasThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Long and Short of Synaptonemal Complex Assembly: Investigating the genesis and functional relevance of a smaller Zip1 isoform
Authors: Shames Alexander , MacQueen Amy J. 
Published: June 2021

The proper segregation of homologous chromosomes (homologs) during meiosis is a paramount task for living cells. Homologs successfully disjoin from one another on the meiosis I spindle so long as they have undergone prior alignment and have formed at least one crossover attachment. The Zip1 protein promotes an intimate alignment between homologs during budding yeast meiosis through its role as a building block of the synaptonemal complex (SC), a proteinaceous structure that assembles along the full length of aligned partner chromosomes. Independent of its role in building SC, Zip1 also plays a critical role in promoting interhomolog crossover recombination, although the molecular underpinnings of this activity are unclear. Through a structure‐function study to identify residues that are essential for Zip1's crossover recombination or SC assembly functions, we identified two zip1 mutants that produce an unexpectedly smaller form of Zip1. In meiotic cells that express either a zip1 allele in which six contiguous residues are changed to alanine, or an allele in which only two of the aforementioned six residues are changed to alanine, a large fraction of Zip1 migrates on a protein gel as if it has lost ten kilodaltons of its wild‐type molecular weight. The change in apparent molecular weight of Zip1 observed in our mutants raises the unanticipated possibility that most Zip1 proteins within the wild‐type meiotic cell are constitutively modified, perhaps by a ten kilodalton protein, and that this post‐translational modification is dependent on the residues that are altered in our two zip1 mutant alleles. Here we describe the results of two experiments designed to ask whether Zip1 in wild‐type meiotic nuclei is constitutively modified by the SUMO protein. First, we will examine the apparent size of Zip1 protein when two SUMO ligase proteins, Siz1 and Siz2, are simultaneously removed. Second, we will determine whether Zip1's molecular weight appears increased in a strain that expresses a larger molecular weight version of SUMO, 3xHA‐SUMO. Finally, we will examine SC assembly and crossover recombination in the two zip1 mutant strains that produce the putative unmodified form of Zip1, in order to determine a function for this potential post‐translational modification.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Molecular insights into replication‐associated genome instabilities caused by CST deficiency
Authors: Chai Weihang 
Published: June 2021

The RPA‐like ssDNA binding protein complex CTC1/STN1/TEN1 (CST) has recently been implicated in promoting genome stability under replications stress. Deficiency in CST genes cause the Coats plus syndrome, a complex genetic disorder affecting multiple systems including brain, retina, bone, gastrointestine, and other parts of the body. Yet the precise role of CST in countering replications stress is unclear. Recently we have reported that CST is enriched at GC‐rich and repetitive fragile sequences genome‐wide in response to hydroxyurea (HU)‐induced replication stress (Chastain et al, 2016, Cell Rep 16, 1300–1314). CST deficiency leads to spontaneous chromosome breakage and high‐level chromosome fragmentation that can be further exacerbated by replication stress. Mechanistically, we have found that upon fork stalling, CST proteins form distinct nuclear foci that colocalize with RAD51. Furthermore, replication stress induces physical association between CST with RAD51 in an ATR‐dependent and DNA‐independent manner. Strikingly, CST deficiency diminishes HU‐induced RAD51 foci formation and reduces RAD51 recruitment to GC‐rich fragile sequences. Collectively, our findings establish that CST promotes RAD51 recruitment to GC‐rich repetitive sequences in response to replication stress to facilitate replication restart, thereby providing insights into the mechanism underlying genome stability maintenance. In the present research, we characterize eleven reported disease‐causing CTC1 missense mutations in maintaining genome stability. Our results show that these mutations induce spontaneous chromosome breakage that leads to global genome instabilities. These mutations abolish or reduce CST interaction with RAD51, disrupt RAD51 foci formation, and/or diminish binding to GC‐rich genomic fragile sites under replication stress. Furthermore, CTC1 mutations limit cell proliferation under unchallenged condition and significantly reduce clonal viability under replication stress. Our findings thus provide molecular evidence linking replication‐associated genomic defects with Coats plus disease pathology.Support or Funding InformationResearch is supported by NIH R01GM112864.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Rad53p Activation Alters Chromatin Structure, Induces Respiration and Elevates Cellular ATP Level
Authors: Bu Pengli , Shah Ankita , Zeng Joey , Bhagwat Madhura S. , Nagar Shreya , Vancura Ales 
Published: June 2021

Rad53p is an essential kinase in the DNA damage response in Saccharomyces cerevisiae. Here we show that activation of Rad53p, either via genetic manipulation or by treatment with genotoxic chemicals, induces mitochondrial respiration. Activation of Rad53p results in reduced transcription of histone genes and globally decreased DNA nucleosome occupancy. This globally altered chromatin structure leads to increased expression of genes encoding enzymes of tricarboxylic acid cycle (TCA), electron transport chain (ETC), and oxidative phosphorylation (OXPHOS) and increased mitochondrial DNA (mtDNA) copy number, oxygen consumption, and ATP synthesis. These findings are surprising and counterintuitive, since it is widely believed that DNA damage results in downregulation of oxidative metabolism to protect DNA from the effects of reactive oxygen species, produced during ETC and OXPHOS. However, our results indicate that the elevated ATP synthesis improves cell survival under conditions of DNA damage and Rad53p activation. In summary, our study reveals a novel role for Rad53p activation in the restructuring of global nucleosomal chromatin architecture and concomitant metabolic transition from fermentation to respiration.Support or Funding InformationSupported by NIH GM120710This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.