bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recruitment of inflammatory cells to the bladder endothelium exposed to cigarette smoke extract (669.1)
Authors: Marentette John , McHowat Jane 
Published: June 2021

Interstitial cystitis/painful bladder syndrome (IC/PBS) is a debilitating disease of unknown etiology. Several risk factors are associated with IC/PBS including smoking, weight and diet. Platelet activating factor (PAF) plays a role in inflammatory cell recruitment to the endothelium and we have shown that PAF metabolism by PAF‐acetylhydrolase (PAF‐AH) is inhibited by cigarette smoke. We propose that cigarette smoking inhibits bladder endothelial PAF‐AH activity and contributes directly to inflammatory cell recruitment in the bladder wall. Incubation of human bladder microvascular endothelial cells (HBMEC) with cigarette smoke extract (CSE, 20 µg/mL) resulted in a significant inhibition of PAF‐AH activity with increased PAF accumulation and polymorphonuclear leukocyte (PMN) adherence. Pretreatment of HBMEC with (S)‐bromoenol lactone to inhibit calcium‐independent phospholipase A2β and PAF production prior to CSE incubation lead to a significant reduction in PMN adherence to the bladder endothelium. Similarly, pretreatment of PMN with PAF receptor antagonists (WEB 4086 or Ginkgo biloba) prior to CSE caused a significant reduction in PMN adherence. We propose that targeting endothelial cell PAF production or blocking the PAF receptor may represent novel therapies for management of IC/PBS patients, particularly smokers.Grant Funding Source: Supported by a President's Research Fund, Saint Louis University grant
Drug carrier particle adhesion depends on bifurcation angle (675.1)
Authors: Lamberti Giuseppina , Smith Ashley , Kiani Mohammad , Prabhakarpandian Balabhaskar , Pant Kapil 
Published: June 2021

In this study, Idealized Microvascular Networks (IMN) representing different angles observed in the microcirculation were used to investigate the effect of bifurcation angle on drug carrier particle interaction with the vessel wall. IMN was fabricated using soft lithography processes followed by study of adhesion of biotin‐conjugated microspheres (diameter 2 µm) to avidin coated vessel walls. The networks used in these studies comprised bifurcation angles of 30°, 60°, 90°, and 120°.Our findings indicate that particle adhesion decreased with increase in shear rate in both bifurcations and linear areas of the channels. However, bifurcations were found to have significantly higher particle adhesion (1.5X or more) compared to linear channels. Furthermore, particle adhesion was found to increases linearly with an increase in the bifurcation angle.Our results show that drug carrier particle adhesion is significantly affected by the presence of bifurcations and their corresponding angle and therefore their design needs to be tailored to account for higher binding propensity at larger bifurcation angles.
Evaluation of sex‐specific endothelial cell actin fiber orientation (675.2)
Authors: Stockard Kevin , Bingaman Susan , Huxley Virginia 
Published: June 2021

Cardiovascular disease with subsequent heart failure is the leading cause of morbidity and mortality in the Western world. Sex disparities with regard to cardiovascular function at the cellular level have received minimal attention in either macro‐ or micro‐ vasculature. We hypothesized that structural differences exist between male and female endothelial cells (EC) isolated and cultured from three vessel types: aorta (macrovessel) and mesenteric and skeletal muscle microvessels. Atomic force microscopy was used to image all cell types for both sexes. Raw deflection images, height profiles, and color maps revealed sex differences in actin fiber orientation amongst all cell types. Profiles of frequency vs. fiber direction were also computed and graphed. Dominant actin fractal dimensions (DAFD) of each cell type were calculated. The DAFD was consistently larger in females (F) than in males (M): 53% larger in aorta; 39% larger in mesentery; and 171% larger in skeletal muscle vessel. These differences indicate that the overall actin fiber orientation of EC from F converges in one direction more uniformly than from M, consistent with a more organized arrangement of fibers in F EC. Knowledge of sex similarities and differences of microvascular EC phenotype may yield clues as to their structural properties (e.g. elastic moduli). These properties may translate to characteristics of the intact vessel and could serve as a starting point to understand sex differences in cardiovascular outcomes.Grant Funding Source: Supported by: DK095501, HCO6RR17353, & the MU Pulmonary/MPP Partnership
In vivo and ex vivo dysfunction of neurovascular coupling in a mouse model of subarachnoid hemorrhage (676.3)
Authors: Koide Masayo , Dunn Kathryn , Bulkeley Evelyn , Nelson Mark , Wellman George 
Published: June 2021

Neurovascular coupling (NVC) represents activity‐dependent focal increases in cerebral blood flow (CBF) crucial for the enhanced delivery of nutrients to maintain brain function in regions of high metabolic demand. We have previously reported inversion of NVC, with neuronal activation causing vasoconstriction rather than vasodilation, in brain slices from subarachnoid hemorrhage (SAH) model rats (Koide et al, 2012). Here, we examined ex vivo NVC, in vivo functional hyperemia and sensory motor function using a mouse endovascular perforation SAH model. In brain slices, astroctyic endfoot Ca2+ and adjoining parenchymal arteriolar diameter were measured using two‐photon and infrared‐differential interference contrast microscopy. Neuronal activation caused increased endfoot Ca2+ that was followed by an inverted neurovascular response (i.e. vasoconstriction rather than vasodilation) in ~ 80% of brain slices from day 1 and day 2 SAH mice and ~ 30% of slices from SAH day 4 mice. In vivo functional hyperemia (whisker stimulation‐induced CBF increases) measured by laser Doppler flowmetry in SAH day 1 mice was also significantly attenuated. Consistent with impaired NVC, SAH mice showed a decreased ability to perform sensory motor tasks. These data demonstrate dysfunction of neurovascular coupling occurs both ex vivo and in vivo following SAH, which may contribute to the development of neuronal deficits. Grant Funding Source: Supported by Totman Research Trust, P. Martin Endowment, NIH P01HL095488, P30RR032135 & P30GM103498.
The sarcoplasmic reticulum enhances voltage‐gated Ca2+ influx in resistance arteries from ovariectomized mice (680.19)
Authors: Hill Brent , Fernando Charmain 
Published: June 2021

Estrogen attenuates Ca2+ entry into arterial smooth muscle cells via its inhibition and/or downregulation of voltage‐gated Ca2+ channels (VGCCs). The purpose of this study is to determine the effect of the sarcoplasmic reticulum (SR) on VGCC function in ovariectomized (OVX) mice. Female mice (C57BL/6) underwent an ovariectomy or sham (SHAM) surgery at 8 wks of age. At 12 wks of age the mice were sacrificed. Compared to SHAM mice, the OVX mice had a 50% decrease in plasma E2 and a 7‐fold reduction in uteri weight. Smooth muscle cells were isolated from the mesenteric arteries and loaded with the ratiometric calcium indicator, fura‐2AM, to conduct fluorescent imaging on these cells. There was an enhanced fura‐2 ratio in cells from OVX mice exposed to the selective VGCC agonist, FPL64176 (1x10‐6 M; p=0.03). However, when the SR was Ca2+ depleted (using the ryanodine receptor agonist, caffeine, and the SR Ca2+‐ATPase pump inhibitor, thapsigargin) before exposing the cells to FPL64176 there was no difference (p=0.40) in the fura‐2 ratio between OVX and SHAM mice. These data suggest that the SR enhances the VGCC‐mediated entry of Ca2+ into smooth muscle cells in mice with low circulating plasma E2 levels. Overall, the decline of circulating estrogen in women can enhance Ca2+ entry into arterial cells. Long‐term this may lead to an elevation in arterial tone in resistance arteries.Grant Funding Source: Supported by NIGMM of the NIH, Grant #P20 GM103429‐11
A mathematical model for epithelial cell wound healing as a diffusion problem (694.6)
Authors: Ogawa Katherine , Nguyen Crystal , Nepomuceno Helene , Hasfura‐Buenaga J. Roberto , Balreira E. Cabral , King Jonathan 
Published: June 2021

Epithelial cells respond to a damaged cell layer by undergoing physiological transitions required for migration and wound closure. We hypothesized that a diffusion model can explain the behavior of this response. Confluent monolayers of Madin‐Darby Canine Kidney (MDCK) cells were used for wounding assays and time‐lapse imaged on a Nikon A1R laser scanning confocal microscope with live cell capability. A diffusion model was developed with a source term for proliferation. A further two‐step process was considered, where after an initial diffusion, the process shifts to a linear progression of movement. A MATLAB code was used to fit the model parameters using the finite‐difference method to determine the best fitting proliferation and diffusion coefficients by minimizing the sum of square errors. Analyses of the model indicated that following a time delay, the diffusion process transitions into a constant rate migration process. This two‐step process provided a better fit than a diffusion process. Future research will aim to associate the diffusion coefficient to the role of key tight junction proteins and the significance of the two‐step process in relation to epithelial cell migration.Grant Funding Source: Supported in part by NSF‐MRI #1229702 and NSF Award #0926702.
Nitroglycerin but not the new NO donor RuBPY phosphorylates eNOS‐Ser1177 (700.4)
Authors: Paulo Michele , Grando Marcella , Vercesi Juliana , da Silva Roberto , Bendhack Lusiane 
Published: June 2021

This study aimed to verify the tolerance induced by RuBPY in rat cava vein and the role of NOS activation. We have analyzed the maximum relaxing effect (ME) induced by GNT and RuBP. In vitro tolerance was induced by 60 min‐exposure to 0.1 µM or 4 µM GTN or 0.1µM or 2µM RuBPY in the presence of L‐NAME, BH4 or tiron. The eNOS phosphorylation in the activation (Ser1177) and in the inactivation site (Thr495) was accessed by Western Blot. The procedures are according to the Ethics Committee. Differences were considered significant for P<0.05. Pre‐exposure for 60 min with 2µM and 10µM RuBPY reduced the ME from 92.7 to 48.0±2.3%, n=7 and 30.1±1.2%, n= 7, respectively. In tolerant vessels, tiron increased the ME induced by GTN from 75.3 to 60.0±4.1%, n=6 and RuBPY (73.0±3.4%, n=6). BH4 increased the ME induced by GTN to 67.4± 3.3%, n=7 and RuBPY to 65.0±2.3%, n=6. L‐NAME increased the ME induced by GNT to 70.3±3.7%, n=6, but it had no effect on RuBPY. Whereas RuBPY and GTN had phosphorylated eNOS in Thr495, only GTN phosphorylated eNOS‐Ser1177. Therefore, tolerance induced by NO donors RuBPY and GTN involves eNOS and O2_. GTN but not RuBPY interferes with the activation site of eNOS.Supported by FAPESP and CNPq.
Differential regulations of ASICs and TRPV1 by zinc in rat bronchopulmonary sensory neurons (712.3)
Authors: Vysotskaya Zhanna , Moss Charles , Gu Qihai 
Published: June 2021

Zinc, a divalent heavy metal ion and an essential trace element in body, functions as a signaling molecule that regulates a variety of neuronal functions. In this study, we examined the effect of zinc on two populations of acid sensitive ion channels, acid‐sensing ion channels (ASICs) and transient receptor potential vanilloid receptor‐1 (TRPV1), in rat bronchopulmonary sensory neurons. In our patch‐clamp recordings, ASIC currents were induced by a pH drop from 7.4 to 6.8 or 6.5 in the presence of capsazepine (10 µM), a specific TRPV1 antagonist. Our data showed that pretreatment with zinc (50 or 300 µM, 2 min) displayed different effects on the two distinct phenotypes of ASIC currents: a marked potentiation on ASIC channels with fast kinetics of activation and deactivation, or no significant effect on ASIC currents with slow activation and deactivation. On the other hand, pretreatment with zinc significantly inhibited the acid (pH 5.3 or 5.5)‐induced TRPV1 currents in these sensory neurons. The inhibition was effectively abolished by the intracellular application of a selective zinc chelator TPEN (25 µM) indicating that the inhibitory effect of zinc on TRPV1 channels depends on its intracellular binding to these channels. In summary, our study showed that zinc differentially regulates the activities of ASICs and TRPV1 channels in rat bronchopulmonary sensory neurons.Grant Funding Source: Supported by funds from AHA, MEDCEN and MUSM
The effectiveness of utilizing pre‐lecture and interactive lecture models on student learning outcomes in undergraduate functional anatomy courses (719.10)
Authors: Domire Zachary , Rider Patrick 
Published: June 2021

Functional anatomy is a challenging course that is required for many undergraduate kinesiology majors. Traditional lecture (TL) models have shown poor results with regards to quiz and exam performance. Pre‐lecture (PL) and interactive lecture (IL) models have shown positive results on class performance outcomes in other scientific disciplines. The objective of this investigation was to determine if utilizing an IL or a PL model would improve quiz and exam performance in undergraduate functional anatomy courses. Quiz and exam performance measures were analyzed from TL (n = 135), IL (n = 193) and PL (n = 22) course delivery models in several sections of a functional anatomy course. All quiz questions and 70% of exam questions were consistent across all sections of the course and used for comparison. A one‐way ANOVA analysis revealed significant differences in exam and final grades. Post‐hoc Student’s t‐tests revealed significant differences in exam and final grades between TL and PL and TL and IL groups, but no differences between PL and IL. See Table 1 for mean and standard deviation values for each group. Quizzes were completed open book therefore; not finding a difference between groups was not surprising. Overall, results indicate that IL and PL models are effective for teaching undergraduate functional anatomy courses and significantly improve student exam and course performance compared to TL.
Table 1: Group Means

Group
Mean Quiz Score %
Mean Exam Score %
Mean Final Course Score %

Traditional
84.1 ± 10.6
78.4 ± 11.2
81.0 ± 10.9

Interactive
84.2 ± 12.0
82.0 ± 11.6*
83.6 ± 11.8*

Pre‐lecture
85.9 ± 11.0
83.8 ± 6.9*
87.7 ± 7.0*

(*) denotes significant difference from traditional group (a < 0.05).
Developing a virtual microscopy laboratory manual to help teach histology in resource‐challenged African medical schools (725.14)
Authors: Anderson Matthew , Cotlin Laura , Anderson Peter 
Published: June 2021

Background: Providing basic science practical laboratory experiences can be problematic especially for new medical schools and in resource challenged schools from less developed parts of the world. The microscopes and glass slide sets needed for robust laboratory sessions are often difficult to procure and to maintain. Virtual Microscopy (VM) can facilitate the teaching of histology, histopathology, microbiology, and other microscopy‐based subjects using a computer based delivery platform. We have developed a VM Histology Laboratory Manual that can be used by students as part of their histology curriculum in medical schools with minimal resources.Design: The UAB histology teaching program has developed a histology laboratory manual that students use as a guide in our histology curriculum. We scanned the histology glass slide collection and incorporated links to these VM slide files into our histology laboratory manual. The PDF of the manual with the VM slide links was locked as a read‐only file and along with the VM slide files was loaded onto inexpensive 64 GB thumb drives. The thumb drives containing the laboratory manual and VM slides, along with the free VM slide viewer, can be used by medical students as a histology teaching resource even in the absence of internet access.Conclusion: Repurposing existing teaching materials utilizing VM technology can provide an inexpensive user‐friendly option for resource challenged African medical schools.
DNA‐PKcs activates the Chk2‐Brca1 pathway during mitosis to ensure chromosomal stability (736.4)
Authors: Chen Benjamin , Shang Zengfu 
Published: June 2021

The catalytic subunit of DNA‐dependent protein kinase (DNA‐PKcs) is known to play a critical role in DNA double‐strand break repair. We previously reported that DNA‐PKcs is activated when cells enter mitosis and functions in mitotic spindle assembly and chromosome segregation. Here we report that DNA‐PKcs is the upstream regulator of the Chk2‐Brca1 pathway, which impacts microtubule dynamics, kinetochore attachment, and chromosomal segregation in mitosis. Downstream from Chk2, Brca1 promotes monoubiquitination of γ‐tubulin to inhibit microtubule nucleation and growth. We found that DNA‐PKcs is essential for mitotic Chk2 phosphorylation at Thr68. As in Chk2‐ and Brca1‐deficient cells, loss of DNA‐PKcs resulted in chromosome misalignment and lagging during anaphase due to elevation in microtubule dynamics. Importantly, these mitotic aberrations in DNA‐PKcs‐defective cells were alleviated by over‐expression of phosphomimetic Chk2 or Brca1 mutant proteins but not their wild‐type counterparts. Taken together, these results demonstrate that DNA‐PKcs regulates mitotic spindle organization and chromosomal instability via the Chk2‐Brca1 signaling pathway.Grant Funding Source: NIH, CA166677
HSF‐1 modulates autophagy via transcriptional regulation of autophagy‐related genes in A549 cells (738.3)
Authors: Dokladny Karol , Moseley Pope 
Published: June 2021

Autophagy is an evolutionary conserved catabolic process employed by eukaryotic cells in response to nutrients starvation, hypoxia, high temperature, and acute exercise. Autophagy, along with other cellular processes, is required for a normal cell function and is responsible for degrading dysfunctional cellular constituents in double‐membrane structures called autophagosomes upon fusion with lysosomes. Recently, we have shown that HSF‐1 knockdown with siRNA increased the LC3 lipidation associated with formation of autophagosomal organelles and augmented both starvation and rapamycin‐induced autophagy. The aim of the present study was to evaluate whether HSF‐1 inhibition by siRNA changes mRNA levels of autophagy related genes in A549 cells (adenocarcinomic human alveolar basal epithelial cells). A549 cells were treated with HSF‐1 siRNA for 48h, total RNA was collected, cDNA was generated, and the quantitative RT‐PCR was performed. Exposure of A549 cells to HSF‐1 siRNA resulted in an increase in LC3, beclin, and Atg12, but not Atg7 mRNA expression. These changes in mRNA expressions were correlated with protein expressions. We conclude that HSF‐1 acts as a negative regulator of autophagy related genes and inhibits autophagy under control conditions.Grant Funding Source: UNM CTSA Grant UL1 TR000041 and UNM School of Medicine Research Allocation Committee Grant
Effect of dimerization of peroxiredoxin 6 on its enzymatic activities (739.4)
Authors: Zhou Suiping , Dodia Chandra , Sorokina Elena , Harper Sandra , Speicher David , Feinstein Sheldon , Fisher Aron 
Published: June 2021

Peroxiredoxin 6 (Prdx6) is a unique non‐seleno 1‐Cys protein with both peroxidase and phospholipase A2 (PLA2) activities. It is highly expressed in the lung where it plays an important role in antioxidant defense and lung surfactant metabolism. Glutathionylation of Prdx6 mediated by πGST is required for its peroxidatic catalytic cycle while its PLA2 activity is enhanced by the presence of GSH. The crystal structure of human Prdx6 reveals a dimer with discrete domains for each activity in each monomer. The N‐terminal domain has a thioredoxin fold and the C‐terminal domain functions in dimerization. We hypothesize that dimerization of Prdx6 might play an important role in its enzymatic activities and have predicted that amino acid residues L145 and L148 are important for protein dimerization. By analytical ultracentrifugation, protein mutated at L145/148 unlike wild type did not dimerize. Peroxidase activity was dramatically reduced by mutation at either of these sites and abolished by double mutation. However, these mutations had no effect on PLA2 activity. Therefore, the dimerization of Prdx6 plays an important role for its peroxidase but not its PLA2 activity.Grant Funding Source: Supported by NIH grants HL102016 and HL19737
Chaperone‐mediated autophagy is impaired in the lysosomal storage disorder cystinosis (740.2)
Authors: Napolitano Gennaro , Johnson Jennifer , Monfregola Jlenia , Rocca Celine , Cherqui Stephanie , Catz Sergio 
Published: June 2021

Functional lysosomes are essential for autophagosome maturation and clearance of autophagic substrates. Accordingly, Lysosomal Storage Disorders (LSDs) have been associated with autophagy defects. Cell malfunction in the LSD Cystinosis is caused by the accumulation of the amino acid cystine in lysosomes due to genetic defects in the Ctns gene (cystinosin), a lysosomal transporter. Using EM and TIRFM microscopy, we showed that lysosomal number, size and trafficking was affected in Ctns‐/‐ cells. Although the number of autophagosomes was strongly increased in Ctns‐/‐ cells under resting conditions, fusion of autophagosomes with lysosomes, as well as starvation‐induced degradation of the autophagosome marker LC3‐II, was not affected in these cells, indicating that autophagic flux is increased but not impaired in cystinosis. Interestingly, the receptor for chaperone‐mediated autophagy (CMA) LAMP2a, the rate limiting step for CMA, was downregulated and mislocalized in Ctns‐/‐ cells and tissues. Lysosomal translocation and degradation of CMA substrates was defective in Ctns‐/‐ lysosomes, suggesting defective CMA in cystinosis. Reconstitution of Ctns‐/‐ cells with EGFP‐CTNS normalized macroautophagy and partially rescued LAMP2a expression but not localization suggesting underlying trafficking defects in Ctns‐/‐ cells. We propose that defects in CMA contribute to the pathogenesis of cystinosis.Grant Funding Source: Supported by Cystinosis Research Foundation and NIH