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https://www.readbyqxmd.com/read/28545230/nanog-plays-a-hierarchical-role-in-the-transcription-network-regulating-the-pluripotency-and-plasticity-of-adipose-tissue-derived-stem-cells
#1
Maria Pitrone, Giuseppe Pizzolanti, Laura Tomasello, Antonina Coppola, Lorenzo Morini, Gianni Pantuso, Romina Ficarella, Valentina Guarnotta, Sebastio Perrini, Francesco Giorgino, Carla Giordano
The stromal vascular cell fraction (SVF) of visceral and subcutaneous adipose tissue (VAT and SAT) has increasingly come into focus in stem cell research, since these compartments represent a rich source of multipotent adipose-derived stem cells (ASCs). ASCs exhibit a self-renewal potential and differentiation capacity. Our aim was to study the different expression of the embryonic stem cell markers NANOG (homeobox protein NANOG), SOX2 (SRY (sex determining region Y)-box 2) and OCT4 (octamer-binding transcription factor 4) and to evaluate if there exists a hierarchal role in this network in ASCs derived from both SAT and VAT...
May 23, 2017: International Journal of Molecular Sciences
https://www.readbyqxmd.com/read/28544834/in-vitro-pulsatile-flow-measurement-in-prosthetic-heart-valves-an-inter-laboratory-comparison
#2
Stephen M Retta, Jeff Kepner, Salvador Marquez, Bruce A Herman, Mark C S Shu, Laurence W Grossman
BACKGROUND AND AIM OF STUDY: One of the first steps in qualifying a new prosthetic valve for eventual clinical use is preclinical flow performance testing in vitro. Such testing is typically performed in an in-vitro test system that simulates the pumping mechanics of the left ventricle of the heart, generally referred to as a pulse duplicator or duplicator. Historically, test results in these systems have varied from duplicator to duplicator. This collaborative effort between heart valve manufacturers and the Food and Drug Administration (FDA) was designed to evaluate the variability of the pulse duplicator test technology for pulsatile flow performance measurement in an interlaboratory round robin...
January 2017: Journal of Heart Valve Disease
https://www.readbyqxmd.com/read/28544741/diagnostic-accuracy-of-a-hybrid-approach-of-instantaneous-wave-free-ratio-and-fractional-flow-reserve-using-high-dose-intracoronary-adenosine-to-characterize-intermediate-coronary-lesions-results-of-the-pals-practical-assessment-of-lesion-severity-prospective
#3
Fernando Rivero, Javier Cuesta, Teresa Bastante, Amparo Benedicto, Marcos García-Guimaraes, Manuel Fuentes-Ferrer, Teresa Alvarado, Fernando Alfonso
OBJECTIVES: We sought to investigate the diagnostic accuracy of instantaneous wave-free ratio (iFR) and high-dose intracoronary adenosine fractional flow reserve (IC-FFR) compared with classical intravenous adenosine fractional flow reserve (IV-FFR) to assess coronary stenosis severity. The usefulness of two hybrid strategies combining iFR and high-dose IC-FFR was also evaluated. BACKGROUND: Physiological assessment of intermediate coronary stenoses to guide revascularization is currently recommended...
May 22, 2017: Catheterization and Cardiovascular Interventions
https://www.readbyqxmd.com/read/28544108/elevated-intrathoracic-co2-pressure-during-thoracoscopic-surgery-decreases-regional-cerebral-oxygen-saturation-in-neonates-and-infants-a-pilot-study
#4
Felix Neunhoeffer, Steven W Warmann, Michael Hofbeck, Alisa Müller, Frank Fideler, Guido Seitz, Martin U Schuhmann, Hans-Joachim Kirschner, Matthias Kumpf, Jörg Fuchs
BACKGROUND: Intraoperative hypercapnia and acidosis are risk factors during thoracoscopy in neonates and infants. METHODS: In a prospective pilot study, we evaluated the effects of thoracoscopy in neonates and infants on cerebral microcirculation, oxygen saturation, and oxygen consumption. Regional cerebral oxygen saturation and blood flow were measured noninvasively using a new device combining laser Doppler flowmetry and white light spectrometry. Additionally, cerebral fractional tissue oxygen extraction and approximated oxygen consumption were calculated...
May 24, 2017: Paediatric Anaesthesia
https://www.readbyqxmd.com/read/28543102/low-flow-low-gradient-aortic-stenosis-still-a-diagnostic-and-therapeutic-challenge
#5
REVIEW
Anja Vogelgesang, Gerd Hasenfuss, Claudius Jacobshagen
Aortic stenosis (AS) is the most frequently observed valvular heart disease. During the symptomatic stage, the rate of death increases dramatically, so that a precise diagnostic approach is taken to guide therapeutic options. Of patients with severe AS, 30% to 50% present with low-flow/low-gradient AS (LF/LGAS) status. This review focuses on LF/LGAS and the best diagnostic and therapeutic management in either classic LF/LGAS with reduced left ventricular ejection fraction (LVEF) or paradoxical LF/LGAS with preserved LVEF...
May 23, 2017: Clinical Cardiology
https://www.readbyqxmd.com/read/28541936/influence-of-substrate-depth-and-particle-size-on-phosphorus-removal-in-a-surface-flow-constructed-wetland
#6
Cui Lijuan, Li Wei, Zhou Jian, Zhang Yan, Zhang Manyin, Lei Yinru, Kang Xiaoming, Zhao Xinsheng, Pan Xu
Substrate adsorption is one of the main processes by which redundant phosphorus is removed from wastewater in surface flow constructed wetlands (SFCWs). The physical properties of the substrate, such as depth and particle size, will influence the amount of phosphorus adsorption. This study was carried out in a long-running intermittent inflow constructed wetland that covered a total area of 940.4 m(2) in the Shunyi District of Beijing, China. We investigated how the concentrations of four phosphorus fractions, namely calcium phosphate (CaP), iron phosphate (FeP), adsorbed phosphorus (AdsP), and organic phosphorus (OP), varied between the surface (0-10 cm) and subsurface (10-20 cm) substrate and among the different substrate particle sizes...
May 2017: Water Science and Technology: a Journal of the International Association on Water Pollution Research
https://www.readbyqxmd.com/read/28540210/integration-of-non-invasive-functional-assessments-with-anatomical-risk-stratification-in-complex-coronary-artery-disease-the-non-invasive-functional-syntax-score
#7
REVIEW
Carlos Collet, Yoshinobu Onuma, Yosuke Miyazaki, Marie-Angèle Morel, Patrick W Serruys
Since the early days of coronary angiography, the extension and severity of coronary artery disease (CAD) have been used for risk stratification. The SYNTAX score objectively characterizes CAD in patients with multivessel disease. Furthermore, recalculating the SYNTAX score by the incorporation of the functional component coronary stenosis (i.e., FFR) increases the discrimination for the risk of adverse events. The calculation of the SYNTAX score derived from non-invasive modalities such as coronary computed tomography angiography (CTA) has emerged as a mean to obtain the SYNTAX score before invasive cardiac catheterization...
April 2017: Cardiovascular Diagnosis and Therapy
https://www.readbyqxmd.com/read/28540209/myocardial-blood-flow-quantification-for-evaluation-of-coronary-artery-disease-by-computed-tomography
#8
REVIEW
Filippo Cademartiri, Sara Seitun, Alberto Clemente, Ludovico La Grutta, Patrizia Toia, Giuseppe Runza, Massimo Midiri, Erica Maffei
During the last decade coronary computed tomography angiography (CTA) has become the preeminent non-invasive imaging modality to detect coronary artery disease (CAD) with high accuracy. However, CTA has a limited value in assessing the hemodynamic significance of a given stenosis due to a modest specificity and positive predictive value. In recent years, different CT techniques for detecting myocardial ischemia have emerged, such as CT-derived fractional flow reserve (FFR-CT), transluminal attenuation gradient (TAG), and myocardial CT perfusion (CTP) imaging...
April 2017: Cardiovascular Diagnosis and Therapy
https://www.readbyqxmd.com/read/28540075/fractional-flow-reserve-to-guide-surgical-coronary-revascularization
#9
REVIEW
Tara Shah, Joshua D Geleris, Ming Zhong, Rajesh V Swaminathan, Luke K Kim, Dmitriy N Feldman
Coronary angiography has traditionally been used as the final diagnostic tool in the evaluation of coronary artery disease (CAD). However, conventional angiography identifies anatomically obstructive coronary disease, but it is limited in its ability to identify hemodynamically significant lesions. The emergence of fractional flow reserve (FFR) technology, in conjunction with angiography, offers a functional, as well as anatomic, assessment of epicardial coronary obstructions. Several pivotal studies have demonstrated that FFR-guided coronary revascularization is a safe and effective in patients with single and multivessel CAD...
April 2017: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/28540060/microparticle-formation-in-peritoneal-dialysis-a-proof-of-concept-study
#10
Shareef Akbari, Rima Abou-Arkoub, Suzy Sun, Swapnil Hiremath, Arkadiy Reunov, Brendan B McCormick, Marcel Ruzicka, Dylan Burger
BACKGROUND: Injury to the mesothelial layer of the peritoneal membrane during peritoneal dialysis (PD) is implicated in loss of ultrafiltration capacity, but there are no validated biomarkers for mesothelial cell injury. Microparticles (MPs) are 0.1 to 1.0 µm membrane vesicles shed from the cell surface following injury and are sensitive markers of tissue damage. Formation of MPs in the peritoneal cavity during PD has not been reported to date. METHODS: We designed a single-center, proof of concept study to assess whether peritoneal solution exposure induces formation of mesothelial MPs suggestive of PD membrane injury...
2017: Canadian Journal of Kidney Health and Disease
https://www.readbyqxmd.com/read/28539713/content-determination-of-phenylpropanoids-and-enhancing-exercise-ability-of-effective-fractions-in-pedicularis-densispica
#11
Hongbiao Chu, Zhihua Zhang, Dong Chen, Xi Wang, Qilong Tu
BACKGROUND: Most researches were focused on chemical constituents and bioactivities of Pedicularis. However, there were a few reports on simultaneous determination of the series phenylpropanoids compounds in Pedicularis by High Performance Liquid Chromatography (HPLC). OBJECTIVE: To establish an HPLC method for simultaneous determination of salidroside, verbascoside, iso-verbascoside, leucoseptoside A, jionoside D and martynoside in Pedicularis densispica (PD), and to assess the enhancing exercise ability of effective fractions of phenylpropanoids (EFP)...
April 2017: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/28539585/natural-convection-flow-of-a-nanofluid-in-an-inclined-square-enclosure-partially-filled-with-a-porous-medium
#12
A I Alsabery, A J Chamkha, H Saleh, I Hashim
This work analyses free convection flow of a nanofluid in an inclined square enclosure consisting of a porous layer and a nanofluid layer using the finite difference methodology. Sinusoidal temperature boundary conditions are imposed on the two opposing vertical walls. Nanofluids with water as base and Ag or Cu or Al2O3 or TiO2 nanoparticles are considered for the problem. The related parameters of this study are the Darcy number, nanoparticle volume fraction, phase deviation, amplitude ratio, porous layer thickness and the inclination angle of the cavity...
May 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28539573/identification-of-the-state-of-maximal-hyperemia-in-the-assessment-of-coronary-fractional-flow-reserve-using-non-invasive-electrical-velocimetry
#13
Takahide Murasawa, Masao Takahashi, Masahiro Myojo, Arihiro Kiyosue, Atsushi Oguri, Jiro Ando, Issei Komuro
Previous research revealed that, in patients with coronary pressure-derived fractional flow reserve (FFR) in the 'grey zone' (0.75-0.85), repeated FFR assessments sometimes yield conflicting results. One of the causes of the fluctuations in FFR values around the grey zone may be imprecise identification of the point where maximal hyperemia is achieved. Identification of the state of maximal hyperemia during assessment of FFR can be challenging. This study aimed to determine whether non-invasive electrical velocimetry (EV) can be used to identify the state of maximal hyperemia...
May 23, 2017: International Heart Journal
https://www.readbyqxmd.com/read/28539480/identification-of-vortex-structures-in-a-cohort-of-204-intracranial-aneurysms
#14
Nicole Varble, Gabriel Trylesinski, Jianping Xiang, Kenneth Snyder, Hui Meng
An intracranial aneurysm (IA) is a cerebrovascular pathology that can lead to death or disability if ruptured. Abnormal wall shear stress (WSS) has been associated with IA growth and rupture, but little is known about the underlying flow physics related to rupture-prone IAs. Previous studies, based on analysis of a few aneurysms or partial views of three-dimensional vortex structures, suggest that rupture is associated with complex vortical flow inside IAs. To further elucidate the relevance of vortical flow in aneurysm pathophysiology, we studied 204 patient IAs (56 ruptured and 148 unruptured)...
May 2017: Journal of the Royal Society, Interface
https://www.readbyqxmd.com/read/28539197/candidatus-neoehrlichia-mikurensis-and-borrelia-burgdorferi-sensu-lato-detected-in-the-blood-of-norwegian-patients-with-erythema-migrans
#15
H Quarsten, A Grankvist, L Høyvoll, I B Myre, T Skarpaas, V Kjelland, C Wenneras, S Noraas
The most common tick-borne human disease in Norway is Lyme borreliosis. Ticks in Norway also harbour less known disease-causing agents such as Candidatus Neoehrlichia mikurensis, Borrelia miyamotoi and Rickettsia helvetica. However, human infections caused by these pathogens have never been described in Norway. The main aims of the study were to evaluate the contribution of several tick-borne bacterial agents, other than Borrelia burgdorferi sensu lato, to zoonotic diseases in Norway and to determine their clinical pictures...
May 13, 2017: Ticks and Tick-borne Diseases
https://www.readbyqxmd.com/read/28538960/diagnostic-accuracy-of-computed-tomography-derived-fractional-flow-reserve-a-systematic-review
#16
Christopher M Cook, Ricardo Petraco, Matthew J Shun-Shin, Yousif Ahmad, Sukhjinder Nijjer, Rasha Al-Lamee, Yuetsu Kikuta, Yasutsugu Shiono, Jamil Mayet, Darrel P Francis, Sayan Sen, Justin E Davies
Importance: Computed tomography-derived fractional flow reserve (FFR-CT) is a novel, noninvasive test for myocardial ischemia. Clinicians using FFR-CT must be able to interpret individual FFR-CT results to determine subsequent patient care. Objective: To provide clinicians a means of interpreting individual FFR-CT results with respect to the range of invasive FFRs that this interpretation might likely represent. Evidence Review: We performed a systematic review in accordance with guidelines from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses...
May 24, 2017: JAMA Cardiology
https://www.readbyqxmd.com/read/28538414/clinical-predictors-for-the-manifestation-of-late-gadolinium-enhancement-after-acute-myocardial-infarction
#17
Nadine Abanador-Kamper, Lars Kamper, Marc Vorpahl, Hilmar Brinkmann, Vasiliki Karamani, Patrick Haage, Melchior Seyfarth
Despite prompt revascularization, some patients with acute myocardial infarction (AMI) develop myocardial scars, which can be visualized by late gadolinium enhancement (LGE) in cardiovascular magnetic resonance imaging (CMR). Our goal was to identify angiographic findings that were predictive for scar development in patients after reperfused AMI.We examined 136 patients after first ST-elevated myocardial infarction by CMR after a median of 4 days (range: 2-7). Patients with manifestation of LGE were matched to patients without LGE by means of age and gender...
May 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28538000/revascularization-for-patients-with-diabetes-mellitus-and-stable-ischemic-heart-disease-an-update
#18
G B John Mancini, Michael Farkouh, Subodh Verma
PURPOSE OF REVIEW: To provide an update on the management of patients with diabetes mellitus and requiring coronary revascularization. RECENT FINDINGS: Evidence continues to show that patients with diabetes mellitus and ischemic heart disease represent a very high-risk group of patients. Choice of stent appears important for minimizing target lesion and target vessel adverse events with everolimus eluting stents having the best performance, particularly in patients being treated with insulin...
May 19, 2017: Current Opinion in Cardiology
https://www.readbyqxmd.com/read/28536897/validation-of-myocardial-perfusion-quantification-by-dynamic-ct-in-an-ex-vivo-porcine-heart-model
#19
Gert Jan Pelgrim, Marco Das, Sjoerd van Tuijl, Marly van Assen, Frits W Prinzen, Marco Stijnen, Matthijs Oudkerk, Joachim E Wildberger, Rozemarijn Vliegenthart
To test the accuracy of quantification of myocardial perfusion imaging (MPI) using computed tomography (CT) in ex-vivo porcine models. Five isolated porcine hearts were perfused according to Langendorff. Hearts were perfused using retrograde flow through the aorta and blood flow, blood pressure and heart rate were monitored throughout the experiment. An inflatable cuff was placed around the circumflex (Cx) artery to create stenosis grades which were monitored using a pressure wire, analysing perfusion at several fractional flow reserve values of 1...
May 23, 2017: International Journal of Cardiovascular Imaging
https://www.readbyqxmd.com/read/28536716/on-chip-hydrodynamic-chromatography-of-dna-through-centimeters-long-glass-nanocapillaries
#20
Lian Duan, Levent Yobas
This study demonstrates hydrodynamic chromatography of DNA fragments in a microchip. The microchip contains a highly regular array of nanofluidic channels (nanocapillaries) that are essential for resolving DNA in this chromatography mode. The nanocapillaries are self-enclosed robust structures built inside a doped glass layer on silicon using low-resolution photolithography and standard semiconductor processing techniques. Additionally, the unique nanocapillaries feature a cylindrical inner radius of 600 nm maintained over a length scale of 5 cm...
May 24, 2017: Analyst
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