106 research outputs found
Stability of small non-coding RNA reference gene expression in the rat retina during exposure to cyclic hyperoxia
Purpose: Oxygen-induced retinopathy (OIR) is a robust animal model of human retinopathy of prematurity that readily allows changes in retinal gene and microRNA (miRNA) expression in response to fluctuations in oxygen levels to be studied. We sought to identify small non-coding RNA (ncRNA) genes that showed stable expression upon exposure to varying levels of oxygen, with different developmental stages and in different rat strains, to act as reference genes for normalizing miRNA expression in a rat model of OIR.
Methods: Expression of five small ncRNAs (U6 snRNA, miR-16, U87, 4.5S RNA (H) “Variant 1”, and 5S ribosomal RNA [rRNA]) were tested on a standard RNA pool and representative retinal samples from P5, P6, P9, and P14 from room air– and cyclic hyperoxia–exposed rats using reverse transcription (RT)-qPCR, to assess the effect of developmental stage and exposure to fluctuations in oxygen levels, respectively. Two strains of inbred albino rats, Fischer 344 (F344, resistant to OIR) and Sprague-Dawley rats (SD, susceptible to OIR), were used to assess the effect of rat strain on the stability of the small ncRNAs.
Results: In this rat model of OIR, 5S rRNA expression was variable with strain, fluctuations in oxygen levels, and developmental stage. U6 snRNA was stably expressed with changes in oxygen levels, and minimal variation was observed with strain and developmental stage. MiR-16 showed less stable expression with changes in oxygen levels and between strains compared to U6 snRNA. Some variation in expression in response to developmental stage was also observed. The PCR amplification efficiencies of the U6 snRNA and miR-16 TaqMan assays were 56% and 78%, respectively. U87 and 4.5S RNA (H) “Variant 1” expression varied with strain, exposure to cyclic hyperoxia, and in particular developmental stage, and was at low levels in the neonatal rat retina.
Conclusions: We conclude that U6 snRNA and miR-16 are the most suitable reference RNAs for normalizing miRNA expression, as they are relatively stable with strain, exposure to cyclic hyperoxia, and developmental stage in a rat model of OIR.The work presented was supported by the National Health and Medical Research Council (NHMRC) of Australia and the Ophthalmic Research Institute of Australia (ORIA)
COMPARISON OF ENDOTRACHEAL INTUBATION WITH THE AIRTRAQ AVANT® AND THE MACINTOSH LARYNGOSCOPE DURING INTERMITTENT OR CONTINUOUS CHEST COMPRESSION: A RANDOMIZED, CROSSOVER STUDY IN MANIKINS
BACKGROUND: Endotracheal intubation (ETI) currently is the gold standard of securing an airway during cardio- pulmonary resuscitation.
PURPOSE: The aim of this study was to evaluate ETI with the Airtraq Avant (ATQ) compared to a conventional Macintosh laryngoscope when used by paramedics during resuscitation with and without chest compression (CC).
METHODS: Forty-seven paramedics were recruited into a randomized crossover trial in which each performed ETI with ATQ and MAC in both scenarios. The primary endpoint was time to successful intubation, while secondary endpoints included intubation success, laryngoscopic view on the glottis, dental compression, and rating of the given device.
RESULTS: In the manikin scenario without CC, nearly all participants performed ETI successfully both with ATQ and MAC, with a shorter intubation time using MAC 20.5 s [IQR, 17.5–22], compared to ATQ 24.5 s [IQR, 22–27.5] (p = 0.002). However, in the scenarios with continuous CC, the results with ATQ were signi cantly better than with MAC for all analyzed variables (success of rst attempt at ETI, time to intubation (TTI) [MAC 27 s [IQR, 25.5–34.5], compared to ATQ 25.7s [IQR, 21.5–28.5] (p=0.011), Cormack-Lehane grade and rating). The success rate in scenarios with CC was 82.9% vs. 91.5% for MAC Laryngoscope vs. ATQ, respectively (p=0.021).
CONCLUSIONS: The ATQ provides bene ts in terms of ETI success rate, TTI, and glottic view when compared to MAC during ETI with continuous CC
Restenosis is not associated with stent length in a pig model of coronary stent implantation
Background: The aim of this study was to determine if stent length is by itself a risk factor
for intimal proliferation and restenosis. Long lesions represent an independent risk factor for
restenosis after coronary stent implantation. A longer stented segment might result in a higher
probability of restenosis.
Methods: Twenty-two 7-month-old male farm pigs underwent implantation of two steel
stents, one short (8 mm length) and one long (16 mm length), in the right coronary artery. The
pigs were sacrificed 28 days after stent implantation and histomorphometric analysis of the
coronary arteries was performed for neointimal area proliferation and area stenosis evaluation.
Results: Seventeen short stents and 19 long stents were finally implanted. There were no
differences in neointimal proliferation (1.84 ± 0.64 mm2 vs. 1.81 ± 0.94 mm2, p = 0.84),
area stenosis (40 ± 9% vs. 41 ± 19%, p = 0.86) and lumen area (2.96 ± 1.30 mm2 vs. 2.51 ±
± 1.18 mm2, p = 0.21) between the short stent group and the long stent group, respectively.
Conclusions: These data suggest that stent length by itself does not influence restenosis extent
in the porcine model
Micromanaging aerobic respiration and glycolysis in cancer cells
© 2019 The Authors. Published by Elsevier GmbH. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)Background
Cancer cells possess a common metabolic phenotype, rewiring their metabolic pathways from mitochondrial oxidative phosphorylation to aerobic glycolysis and anabolic circuits, to support the energetic and biosynthetic requirements of continuous proliferation and migration. While, over the past decade, molecular and cellular studies have clearly highlighted the association of oncogenes and tumor suppressors with cancer-associated glycolysis, more recent attention has focused on the role of microRNAs (miRNAs) in mediating this metabolic shift. Accumulating studies have connected aberrant expression of miRNAs with direct and indirect regulation of aerobic glycolysis and associated pathways.
Scope of review
This review discusses the underlying mechanisms of metabolic reprogramming in cancer cells and provides arguments that the earlier paradigm of cancer glycolysis needs to be updated to a broader concept, which involves interconnecting biological pathways that include miRNA-mediated regulation of metabolism. For these reasons and in light of recent knowledge, we illustrate the relationships between metabolic pathways in cancer cells. We further summarize our current understanding of the interplay between miRNAs and these metabolic pathways. This review aims to highlight important metabolism-associated molecular components in the hunt for selective preventive and therapeutic treatments.
Major conclusions
Metabolism in cancer cells is influenced by driver mutations but is also regulated by posttranscriptional gene silencing. Understanding the nuanced regulation of gene expression in these cells and distinguishing rapid cellular responses from chronic adaptive mechanisms provides a basis for rational drug design and novel therapeutic strategies
Polideportivo ecosostenible en la integraciĂłn intergeneracional en la ciudad de Chachapoyas 2022
La presente investigación ha sido denominada “Polideportivo ecosostenible en la
integración intergeneracional en la ciudad de Chachapoyas 2022”. Se ha
identificado que existe un déficit de infraestructura deportiva y que existe un
potencial climático que favorece la propuesta de diseño eco sostenible, es por ello
que, el objetivo general de la investigación es proyectar un polideportivo con diseño
eco sostenible en la ciudad de Chachapoyas, para reducir el déficit de
infraestructura deportiva y recreativa. La metodologĂa empleada presenta un
enfoque cualitativo, de tipo básica, el diseño es no experimental: Estudio de casos:
Caso 1: El Polideportivo TurĂł de la Peira y caso 2: Polideportivo Camp del Ferro.
La tĂ©cnica empleada es el análisis documental de artĂculos cientĂficos, normas
legales y tĂ©cnicas e informes estadĂsticos, lo que determina la confiabilidad de la
información. El resultado de la investigación señala la importancia del diseño eco
sostenible para la infraestructura deportiva. La investigaciĂłn concluye que el
proyecto de un polideportivo con diseño eco sostenible en la ciudad de
Chachapoyas contribuye a la reducción del déficit de infraestructura deportiva y
recreativa. De esta manera el proyecto se convierte en una propuesta innovadora
que busca mejorar la calidad de vida del poblador de Chachapoya
Systemic hypertension augments, whereas insulin-dependent diabetes down-regulates, endothelin A receptor expression in the mammary artery in coronary artery disease patients
Background: Endothelin (ET) A receptor antagonism causes decreased vasodilation in hypertensive
coronary arteries and decreased effects on coronary artery compliance in diabetic
patients.
Methods: We investigate the mRNA expression of ET-1, ETA and ETB receptors, using real
time RT-PCR, in biopsies from the internal mammary artery obtained from 49 patients,
18 diabetics and 34 hypertensives, all undergoing coronary artery bypass grafting.
Results: Hypertensive patients had higher ET-1 mRNA expression (16438 [8417, 23917]),
than normotensive patients (2974 [2283, 18055], p=0.008). Diabetic patients had significantly
lower ETA receptor levels than non-diabetic patients (455 [167, 1496] vs. 1660 [700,
3190], respectively, p = 0.003).
Conclusions: Multivariate analysis demonstrated that the presence of systemic hypertension
was the only independent predictor of log ETA receptor expression and log ET-1 expression,
while insulin-dependent diabetes was negatively correlated with ETA receptor expression. ETB
receptor expression was not correlated with any predictor. Systemic hypertension is associated
with increased ET-1 and ETA receptor mRNA expression, whereas insulin-dependent diabetes
down-regulates ETA receptor mRNA expression in the internal mammary artery in patients
with coronary artery disease undergoing bypass grafting
Multiple paxillin binding sites regulate FAK function
Abstract Background FAK localization to focal adhesions is essential for its activation and function. Localization of FAK is mediated through the C-terminal focal adhesion targeting (FAT) domain. Recent structural analyses have revealed two paxillin-binding sites in the FAT domain of FAK. To define the role of paxillin binding to each site on FAK, point mutations have been engineered to specifically disrupt paxillin binding to each docking site on the FAT domain of FAK individually or in combination. Results These mutants have been characterized and reveal an important role for paxillin binding in FAK subcellular localization and signaling. One paxillin-binding site (comprised of α-helices 1 and 4 of the FAT domain) plays a more prominent role in localization than the other. Mutation of either paxillin-binding site has similar effects on FAK activation and downstream signaling. However, the sites aren't strictly redundant as each mutant exhibits phosphorylation/signaling defects distinct from wild type FAK and a mutant completely defective for paxillin binding. Conclusion The studies demonstrate that the two paxillin-binding sites of FAK are not redundant and that both sites are required for FAK function
Expression of microRNA in human retinal pigment epithelial cells following infection with Zaire ebolavirus
© The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License
(http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium,
provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license,
and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/
publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Objective: Survivors of Ebola virus disease (EVD) are at risk of developing blinding intraocular inflammation—or uveitis—which is associated with retinal pigment epithelial (RPE) scarring and persistence of live Zaire ebolavirus (EBOV) within the eye. As part of a large research project aimed at defining the human RPE cell response to being infected with EBOV, this work focused on the microRNAs (miRNAs) associated with the infection.
Results: Using RNA-sequencing, we detected 13 highly induced and 2 highly repressed human miRNAs in human ARPE-19 RPE cells infected with EBOV, including hsa-miR-1307-5p, hsa-miR-29b-3p and hsa-miR-33a-5p (up-regulated), and hsa-miR-3074-3p and hsa-miR-27b-5p (down-regulated). EBOV-miR-1-5p was also found in infected RPE cells. Through computational identification of putative miRNA targets, we predicted a broad range of regulatory activities, including effects on innate and adaptive immune responses, cellular metabolism, cell cycle progression, apoptosis and autophagy. The most highly-connected molecule in the miR-target network was leucine-rich repeat kinase 2, which is involved in neuroinflammation and lysosomal processing. Our findings should stimulate new studies on the impact of miRNA changes in EBOV-infected RPE cells to further understanding of intraocular viral persistence and the pathogenesis of uveitis in EVD survivors
MicroRNA signatures in chemotherapy resistant esophageal cancer cell lines
Copyright ©1995-2014 Baishideng Publishing Group Inc. All rights reserved. Articles published by this open-access journal are distributed under the terms of the Creative Commons Attribution-Noncommercial License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited, the use is non commercial and is otherwise in compliance with the license. See: http://creativecommons.org/licenses/by-nc/4.0/AIM: To investigate expression of microRNA (miRNA) and potential targets in chemotherapy resistant esophageal cancer cell lines.
METHODS: An in-vitro model of acquired chemotherapy resistance in esophageal adeno- (EAC) and squamous cell carcinoma (ESCC) cells was used, and microRNA expression profiles for cisplatin or 5-fluorouracil (5-FU) resistant variants vs chemotherapy sensitive controls were compared using microarray and quantitative real-time polymerase chain reaction (PCR). The expression of chemotherapy-relevant genes potentially targeted by the dysregulated microRNAs in the chemotherapy resistant variants was also evaluated.
RESULTS: Chemotherapy resistant sublines were found to have specific miRNA signatures, and these miRNA signatures were different for the cisplatin vs 5-FU resistant cells from the same tumor cell line, and also for EAC vs ESCC cells with resistance to the same specific chemotherapy agent. Amongst others, miR-27b-3p, miR-193b-3p, miR-192-5p, miR-378 a-3p, miR-125a-5p and miR-18a-3p were dysregulated, consistent with negative posttranscriptional control of KRAS, TYMS, ABCC3, CBL-B and ERBB2 expression via these miRNAs.
CONCLUSION: The current study supports the hypothesis that microRNA expression has an impact on chemotherapy resistance in esophageal cancer.
Keywords: Esophageal cancer, MicroRNA, Chemotherapy, Resistance, Targe
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