bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glucocorticoid Receptor Maintains Vasopressin‐Regulated Water Reabsorption Pathway in the Kidney Collecting Duct Cells
Authors: Su Shih-Han , Ho Cheng-Hsuan , Yu Ming-Jiun 
Published: April 2020

Aquaporin‐2 (AQP2) is a transmembrane protein expressed in the principal cells of the kidney collecting ducts, which mediate osmotic water reabsorption. AQP2 is regulated by the antidiuretic peptide hormone arginine vasopressin (AVP). When AVP binds to the vasopressin type 2 receptor (V2R) in the principal cells, it initiates a signaling network that results in 1) AQP2 trafficking to the apical plasma membrane for water transport and 2) AQP2 gene expression. In a previous study, we found that dexamethasone, a glucocorticoid receptor (GR) agonist, enhanced AVP‐induced AQP2 gene expression in the collecting duct cell model mpkCCD. Here, we showed that GR knockdown drastically decreased AVP‐induced AQP2 mRNA and protein levels, indicative of a role of GR in AVP‐induced AQP2 gene expression. We further showed that the 1,000bp region upstream to the AQP2 transcription start site was sufficient to mediate GR‐enhanced AVP‐induced promoter activity and that GR bound to the above AQP2 promoter region. RNA‐seq was used to profile the transcriptome of the GR knockdown vs. control cells. A total of 93,308 transcripts belonging to 22,025 genes were quantified. GR knockdown decreased expression of 5,266 genes and increased expression of 3,709 genes. These two gene groups respectively represent positive and negative regulators for the AVP responses. Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway analysis showed 62 pathways associated with the positive regulators and 48 pathways associated with the negative regulators. The AVP‐regulated water reabsorption pathway was among the 62 positive pathways whose gene expression was reduced upon GR knockdown. Quantitative RT‐PCR analysis showed about 60% reduction in the V2R mRNA level upon GR knockdown. Taken together, our results implicated that GR in one hand potentiates AVP‐induced AQP2 gene expression and in the other hand maintains expression of genes involved in the AVP‐regulated water reabsorption pathway in the kidney collecting duct cells.Support or Funding InformationThis work was supported by the Ministry of Science and Technology, Taiwan (107‐2320‐B‐002‐057‐MY3).
Anti‐Biofilm Properties of Flax, Chia, and Hemp Seed Oil Extracts
Authors: Menjivar Jessica Liseth , Bendaoud Meriem 
Published: April 2020

Biofilm formation is an important virulence factor and a crucial step in the pathogenesis of bacterial infection for certain microorganisms. Bacteria attaching to surfaces and forming biofilms are resistant to antibiotic treatment and antimicrobial agents, which makes them difficult to eradicate. Worldwide, an increasing number of pathogenic bacteria and yeast have been gaining antibiotic and anti‐fungal resistance. This is a critical problem for public health as millions of people acquire infections from pathogenic antibiotic resistant microorganisms such as Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Candida albicans. For many years now, scientists have been looking for natural alternatives like herbs, oils, and seed extracts to control the rise of antibiotic resistant microbial infections and support better health. Chia, Flax, and Hemp seed oil extracts have been found to support skin health and improve immunity and cardiovascular function. However, very little is known about their effects on the growth of pathogenic microorganisms. The purpose of this study is to test these oil‐seed‐extracts for anti‐biofilm properties. Using the biofilm assay we were able to show that Chia seed oil extract and Hemp seed oil extract had the most effective anti‐biofilm properties against P. aeruginosa and S. epidermidis. Preliminary chemical characterization of these oils was initiated to determine the active fraction displaying anti‐biofilm properties. Additional testing will be done to further characterize the active compound in each of these oils.Support or Funding InformationThis project received support from US Education Department Title III Part F HSI grant # P031C160155
Some Believe, Not All Achieve: The Role of Active Learning Practices in Anxiety and Academic Self‐Efficacy in First Generation College Students
Authors: Hull Kerry , Hood Suzanne , Page Olivia , Birdsong-Farr Melaney , Barrickman Nancy , Djerdjian Nancy , Roychowdhury Hiranya , Stowe Skye , Gerrits Ron , Ross Kyla , Ott Betsy , Jensen Murray 
Published: April 2020

Although active learning (AL) techniques improve student performance and persistence in STEM programs of study, AL may provoke anxiety in certain student populations. Given that high anxiety impairs academic performance, there is a need to understand how psychological variables in students interact with AL. As part of a larger study examining the adoption of AL in human anatomy and physiology courses in community colleges, we asked students to rate various teaching strategies in terms of their perceived educational value and their capacity to invoke anxiety. We also examined the relationship of these scores to two psychological constructs: self‐reported social anxiety (psychological distress relating to the fear of negative evaluation by others) and academic self‐efficacy (confidence in one’s ability to overcome academic challenges). In general, the degree of anxiety induced by a teaching strategy was inversely related to its perceived educational value such that the most anxiety‐inducing (e.g., cold calling) were reported as having the least educational value (N=330). Compared to students low in social anxiety, socially anxious students rated all techniques as more anxiety‐inducing and of lower educational value, and anticipated a lower grade in the course. Notably, individual differences in academic self‐efficacy mediated the relationship between social anxiety and anticipated grade. Consistent with this, low‐efficacy students reported more anxiety in response to AL techniques involving a social component (e.g., non‐graded group activities) than did high‐efficacy students. Since mastery experiences (such as those provided by active learning strategies) can significantly improve academic self‐efficiency, our results suggest that anxious students may not benefit from the beneficial and reciprocal relationship between active learning strategies and academic self‐efficacy to the same extent as less anxious students. Other documented strategies that improve academic self‐efficacy, such as the use of trained peer facilitators, may thus facilitate the introduction of AL in the classroom.Support or Funding InformationFunding from the National Science Foundation (Award #1829157)
Investigating EWS‐FLI1 Induced Replication Stress in Ewing Sarcoma Pathogenesis
Authors: Halbkat Halle , Ghosal Gargi 
Published: April 2020

Ewing sarcoma (EWS) is the second most common malignant bone cancer affecting young children and adolescents. Although most patients achieve long‐lasting remission, patients with metastatic or recurrent disease have very poor outcomes and chemo‐resistance is a significant problem. The majority of Ewing sarcomas are driven by a chromosomal translocation resulting in the EWS‐FLI1 fusion gene. EWS‐FLI1 is an oncogenic transcription factor that plays roles in transcriptional regulation, DNA damage response, cell cycle checkpoint control, and alternative splicing. However, the exact molecular mechanisms behind these functions are not understood fully. Although EWS‐FLI1 is specific to EWS cells and required for tumorigenesis, successfully targeting EWS‐FLI1 has proved challenging. Therefore, other therapeutic targets must be identified to improve outcomes for patients with metastatic or recurrent disease.Using a quantitative PCR array, we identified USP1, a deubiquitinase that functions in both the DNA damage and replication stress responses, as being overexpressed in EWS cell lines compared to its cell of origin, the human mesenchymal stem cell. Importantly, we found USP1 to be essential for EWS cell line proliferation, as growth of these cell lines is arrested with knockdown of USP1. USP1 downregulation has been linked to oncogene‐induced cellular senescence dependent on functional p53. However, because p53 is mutated in EWS, the growth arrest we observe following USP1 downregulation must occur via a p53‐independent mechanism. Therefore, we hypothesize that USP1 overexpression functions to bypass cellular senescence in a p53‐independent manner in response to EWS‐FLI1 induced replication stress, resulting in tumorigenesis. Our studies aim to test this hypothesis in EWS and explore the potential to target USP1 alone or in combination with the current chemotherapy regimen for treating EWS.Support or Funding InformationThis work was supported by Pediatric Cancer pilot funding UNMC and UNMC startup funds to Gargi Ghosal and UNMC Graduate Assistantship Fellowship to Halle Halbkat
Pattern of sympathetic vasomotor activity induced by GABAergic inhibition in the brain and spinal cord
Authors: Campos Ruy R. , Milanez Maycon I. , Silva Adilson M. , Perry Juliana C. , Faber Jean , Nishi Erika E. , Bergamaschi Cassia 
Published: April 2020

BackgroundThe knowledge of the central areas involved in the control of sympathetic vasomotor activity has been advanced in the last few decades. The γ‐aminobutyric acid (GABA) is the mainly inhibitory neurotransmitter in the mammal central nervous system and bicuculline, an antagonist of GABA type A receptors (GABA‐A), microinjected into the paraventricular nucleus of the hypothalamus (PVN) alters the pattern of sympathetic vasomotor activity to the renal, splanchnic and lumbar territories. However, studies are needed to clarify the role of GABAergic inputs in other central areas involved in the control of sympathetic vasomotor activity. Thus, the present work studied the cardiovascular effects evoked by GABAergic inhibition in the PVN, RVLM and the spinal cord.Methods and ResultsAll experimental approach applied in this present study agreed to the guidelines recommended by the National Institute of Health and were approved by the Ethics in Research Committee of the Escola Paulista de Medicina – Universidade Federal de São Paulo (8724270715/15). In urethane (1.4 g/kg, iv) Wistar male anesthetized rats, Bicuculline microinjection (400 pMol in 100 nL) into the PVN and rostral ventrolateral medulla (RVLM), as well its intrathecal administration (1.6 nmol in 2 μL) evoked an increase in blood pressure, heart rate, renal and splanchnic sympathetic nerve activity (rSNA and sSNA, respectively) inducing a higher coherence of rSNA and sSNA pattern. However, some of these responses were more intense when the GABA‐A antagonism was performed into the RVLM.ConclusionsAdministration of bicuculline into the RVLM, PVN and SC induced a similar pattern of renal and splanchnic sympathetic vasomotor burst discharge, characterized by a low frequency (0.5 Hz) and high amplitude pattern despite different blood pressure responses. Thus, the 0.5 Hz recorded in sympathetic nerves to different targets is dependent in part of tonic GABAergic inputs in the brain (RVLM and PVN) and spinal cord. The origin of the GABAergic projections is unknown.Support or Funding InformationCAPES ‐ Finance Code 001; FAPESP ‐ 18/02671‐3 and CNPq 309020/2017‐4.
Urinary Angiotensinogen is Essential for Renal Potassium Handling
Authors: Wang Bangchen , Wang-France Jun , Sansom Steven 
Published: April 2020

Apart from the well‐known systemic renin‐angiotensin system (RAS), the urinary RAS acts as a local autocrine/paracrine system along the nephron. The regulation of renal K+ handling by systemic vs urinary RAS remains unclear. Liver‐specific (Alb‐Cre) angiotensinogen knockout (LKO) and liver + proximal tubule (Alb‐Cre + KAP‐Cre) angiotensinogen knockout (DKO) were utilized in this study. WT, LKO, and DKO mice were kept on either a regular diet (RD) or a high K diet (HK; 5% K+) for 10 days. Mice were acclimated to metabolic cages twice before collecting urine for 24 hours. Mice were then euthanized to collect blood and kidneys. Plasma and urinary [Na+] and [K+] were measured by flame photometry. Plasma and urinary angiotensin II (Ang II) concentrations were measured by ELISA (Enzo Life Sciences). Plasma and urinary aldosterone (Aldo) concentrations were measured by ELISA (DRG Diagnostics). Urinary creatinine (Cr) concentrations were measured by colorimetric assays (Cayman Chemical). Plasma [Ang II] was significantly lower in LKO, compared to WT, and the value in DKO was not significantly different from zero. Urinary [Ang II] was significantly lower in DKO compared to WT and LKO. Plasma [K+] was significantly higher in DKO but not LKO compared to WT on HK. Urinary K:Cr ratio was significantly lower in DKO compared to WT on HK. However, plasma and urinary [Aldo] were not different between DKO and WT on HK. Overall, our results showed that urinary RAS but not systemic RAS plays an essential role in renal K handling.Support or Funding InformationThis project was funded by F30 DK108456.
Is skeletal muscle a functional immunosensory organ of pathogens? A murine model of polymicrobial sepsis.
Authors: Robinson Gerard Patrick , Iwaniec John , Alzahrani Jamal , Sheikh Laila , de Carvalho Lucas , Garcia Christian , Murray Kevin , Morse Deborah , Laitano Orlando , Clanton Thomas 
Published: April 2020

The body’s ability to sense lipopolysaccharide (LPS) is critical in the inflammatory response to bacterial infection. LPS is a ligand for toll‐like receptors (TLRs), expressed on immune and many other cell types. When activated, they lead to secretion of cytokines such as IL‐6 and IL‐1ß. These cytokines, in turn, promote the activity and trafficking of inflammatory cells to the site of infection. We hypothesize that skeletal muscle (skm), which also expresses TLRs, plays a role in directing inflammatory cells via cytokine secretion during sepsis. In order to test this, we developed an inducible skeletal muscle‐specific knockdown of MYD88 (an adaptor protein necessary for TLR function) using the Mer‐CRE‐Mer system.METHODSMale and female mice on skmCRE background were injected with raloxifene to induce skmMYD88 knockdown vs. vehicle control (no CRE induction). Three weeks after CRE induction, sepsis was induced via intraperitoneal injection of a calibrated dose of cecal slurry. The animals were sacrificed 6 and 12 hours post‐injection. Plasma and peritoneal lavage were collected at the time of sacrifice, and analyzed for the presence of various inflammatory cells via a HESKA hematological analyzer.RESULTSskmMYD88−/− females showed a significant increase in the %neutrophils in the lavage at both the 6h (P<0.05) and 12h time points (P<0.0001) compared to skmMYD88+/+. The % of lavage basophils were elevated in female skmMYD88−/− at 12h (P< 0.01), as were %eosinophils (P<0.0001). Female lavage %monocytes increased at 12h in skmMYD88−/−. There were no differences in lavage %lymphocytes. No differences between the male skmMYD88−/− were observed for any cell types in the peritoneal lavage. In the blood, the only significant differences were found in males, in which the skmMYD88−/− group displayed increased %monocytes and decreased %lymphocytes at 12h.DISCUSSIONThe data suggest that skeletal muscle is capable of selectively governing the direction and presence of immune cells at the site infection, i.e. the peritoneum. The cause of this influence appears to be, in part, due to skeletal muscle TLR activation. While total leukocytes remain unchanged in the peritoneal lavage, knocking down skmMYD88 resulted an altered immune cell profile during the time‐course of infection. In the case of neutrophils, skeletal muscle appears to play a major suppressive regulatory role. Overall, these results implicate skeletal muscle as a significant player in pathogen recognition and response.Support or Funding InformationSupported by NIH 1R01GM118895 (TLC) and the BK Betty Stevens Endowment
Morphology of the Semicircular Canals and Locomotion of Zionodon satanus
Authors: Dunn Rachel Heather , Penkrot Tonya , Zack Shawn 
Published: April 2020

Zionodon satanus is a relatively large “insectivore” from the Uinta Formation of Utah, known from associated fragmentary dental, cranial, and postcranial elements. Features of the postcrania, particularly the knee and ankle joints, suggest that this species primarily engaged in swift terrestrial locomotion, but with some climbing and digging capability. Among the cranial fragments of Z. satanus are two petrosal bones preserving portions of the bony labyrinth, particularly the semicircular canals, which are known to vary among extant mammals according to locomotor agility, with more agile animals having semicircular canals with a larger radius of curvature than slower ones. Thus, semicircular canal dimensions can provide insight into locomotion independent of postcranial morphology. Here we compare measurements of the semicircular canals of Z. satanus to other extant and extinct mammals to assess the degree of locomotor agility of this species and compare those results to those obtained by functional analysis of the postcrania.The petrosal bones of the type specimen of Z. satanus were microCT scanned and virtual models of the semicircular canals were extracted with AMIRA 6.5.0 software. One petrosal includes a complete posterior and partial lateral semicircular canal, whereas the other preserves a complete lateral, damaged but complete posterior, and most of the anterior semicircular canal. The height and width of each semicircular canal was measured from the extracted surface models and the radius of curvature was calculated from height and width measurements. The average radius of curvature of the semicircular canals of Z. satanus overlaps with extant mammals of similar body size of “fast” or “medium” agility and lies well outside the range of slow‐moving small mammals. Compared to other fossil “insectivores”, Z. satanus has relatively smaller semicircular canals than Leptictidium from the middle Eocene of Messel, Germany, which has been reconstructed as a bipedal runner and saltator, but larger ones than the North American leptictids Paleictops and Leptictis. These results corroborate observations from the postcranial skeleton, suggesting that Z. satanus likely engaged in frequent, rapid locomotion.
CYP11B and CYP17A1 in the Biosynthesis and Metabolism of C11‐oxy Steroids
Authors: Swart Amanda Cecilia , van Rooyen Desmaré , Gent Rachelle , du Toit Therina 
Published: April 2020

Cytochrome P450 (CYP11B1) and cytochrome 17α‐hydroxylase (CYP17A1) play pivotal roles in the biosynthesis of adrenal glucocorticoids and androgens. It is generally accepted that CYP11B1 catalyses only the production of cortisol and corticosterone while CYP17A1 catalyses the hydroxylation of pregnenolone and progesterone at C17 and, in humans, the 17,20‐lyase of 17‐hydroxypregnenolone to produce DHEA. CYP11B1, however, also catalyses the biosynthesis of C11‐oxy C21 steroids, 11β‐hydroxyandrostenedione, 11β‐hydroxyprogesterone (11OHPROG) and 21‐deoxycortisol (21dF) in the adrenal
[1,
2].We investigated the potential role of CYP17A1 in the metabolism of these C11‐oxy C21steroids leading to the production of 11keto‐dihydrotestosterone since 17‐hydroxyprogesterone has been shown to lead to the production of dihydrotestosterone in the backdoor pathway.The 17α‐hydroxylase/17,20‐lyase activity of CYP17A1 towards 11OHPROG and 21dF was assayed as well as the catalytic activity of the enzyme towards the downstream C11‐oxy C21steroid products. In vitro conversions were carried out with 1 μM steroid substrate in HEK293 and in LNCaP cells transiently expressing CYP17A1 and metabolites analysed using UPC2‐MS/MS. Both 11OHPROG and 11keto‐progesterone (11KPROG) were hydroxylated at C17 producing 21dF, 0.27 μM and 21‐deoxycortisone, 0.65 μM, respectively while no lyase activity was detected. It was only once reduced by 5α‐reductase and 3α‐hydroxysteroid dehydrogenase that the aforementioned steroids were also lyased to produce the C11‐oxy C19steroids, 11‐hydroxyandrosterone, 0.6 μM and 11‐ketoandrosterone, 0.43 μM. In LnCaP cells 11OHPROG and 11KPROG were metabolised to C11‐oxy C19steroids indicative of the C11‐oxy backdoor pathway. In addition, in HEK293 cells transiently transfected with 11β‐hydroxysteroid dehydrogenase (11βHSD) type 1 and 11βHSD2 the isozymes readily catalysed the interconversion of all the C11‐keto C21steroid intermediates produced in the pathway with the production of the keto intermediates being favoured.Although the C11‐oxy C21steroids produced in the adrenal may serve as ligands for the progesterone receptor they also potentially add to the pool of potent androgens via the C11‐oxy backdoor pathway. These C11‐oxy steroids would thus further contribute to the androgen pool in adrenal disorders and diseases characterised by androgen excess in which these steroids have been identified. We recently reported 11OHPROG, 11keto‐dihydroprogesterone and pregnanetriol in circulation in BPH patients
[3]. The C11‐oxy C21steroids and C11‐oxy C19steroids, however, remain to be fully explored –not only in pathophysiology but also in sexual differentiation and development.Support or Funding InformationThe South African National Research Foundation (IFR170125217588, CSUR160414162143)
Cigarette smoke extract increases expression and plasma membrane trafficking of α2C ‐ adrenoceptors in human microvascular smooth muscle cells
Authors: Maaliki Dina Salem , Eid Ali H. 
Published: April 2020

Vasoconstriction of cutaneous arterioles in response to cold temperatures or emotion is a normal adaptive process in which the body diverts blood flow from the superficial circulation to internal organs to prevent heat loss. This is mediated by increased sympathetic activation as well as increased sensitivity of the digital arteriolar vascular smooth muscle to vasoconstrictors. When cold‐induced constriction is exacerbated, Raynaud’s phenomenon (RP) is precipitated. Remarkably, the entirety of this augmented cold‐induced vasoconstriction is mediated by α2Cadrenoceptors (α2C‐ARs) . We have previously established that cooling induces translocation of α2C‐ARs from the Golgi compartment, where they are trapped, to the plasma membrane of microvascular smooth muscle cells.Epidemiological studies show that cigarette smoking is a significant risk factor for RP. Here, we provide exciting evidence which shows that cigarette smoke extract (CSE) increases α2C‐AR protein expression in a concentration and time‐dependent manner in human arteriolar smooth muscle cells. This expression appears to be due to increased transcriptional activity of the α2C‐AR promoter since pretreatment with actinomcyin D, a transcription inhibitor, abolished CSE‐induced α2C‐AR protein expression. Moreover, CSE increased transcriptional activity of α2C‐AR promoter: reporter construct. Interestingly, apocynin, a ROS scavenger, abolished CSE‐induced α2C‐AR protein expression, indicative of a ROS‐mediated pathway. CSE also increased RhoA activation, a pathway that we have previously established to drive trafficking of α2C‐ARs to the membrane. Indeed, CSE evoked mobilization of α2C‐ARs to the cell membrane. Taken together, these results may explain the underlying mechanism of CSE‐exacerbated cold‐induced vasoconstriction and provide an alternative avenue for treatment of patients who have RP and are smokers.Support or Funding InformationThis publication was made possible by an MPP fund (#320133) from the American University of Beirut to Ali Eid