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https://www.readbyqxmd.com/read/28088672/using-discrete-multi-physics-for-detailed-exploration-of-hydrodynamics-in-an-in-vitro-colon-system
#1
A Alexiadis, K Stamatopoulos, W Wen, H K Batchelor, S Bakalis, M Barigou, M J H Simmons
We developed a mathematical model that describes the motion of viscous fluids in the partially-filled colon caused by the periodic contractions of flexible walls (peristalsis). In-vitro data are used to validate the model. The model is then used to identify two fundamental mechanisms of mass transport: the surfing mode and the pouring mode. The first mechanism is faster, but only involves the surface of the liquid. The second mechanism causes deeper mixing, and appears to be the main transport mechanism. Based on the gained understanding, we propose a series of measures that can improve the reliability of in-vitro models...
January 9, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/28088635/mucoadhesive-amorphous-solid-dispersions-for-sustained-release-of-poorly-water-soluble-drugs
#2
Justin S LaFountaine, Leena Kumari Prasad, Dave A Miller, James W McGinity, Robert O Williams
The oral delivery of mucoadhesive patches has been shown to enhance the absorption of large molecules such as peptides. We hypothesized that this mechanism could have utility for poorly soluble small molecules by utilizing a mucoadhesive polymer as the matrix for an amorphous solid dispersion. Binary dispersions of itraconazole and carbomer (Carbopol 71G) were prepared utilizing a thermokinetic mixing process (KinetiSol Dispersing) and the physicochemical properties were investigated by powder x-ray diffraction, calorimetry, and liquid chromatography...
January 11, 2017: European Journal of Pharmaceutics and Biopharmaceutics
https://www.readbyqxmd.com/read/28088142/colloidal-transport-by-active-filaments
#3
Raj Kumar Manna, P B Sunil Kumar, R Adhikari
Enhanced colloidal transport beyond the limit imposed by diffusion is usually achieved through external fields. Here, we demonstrate the ballistic transport of a colloidal sphere using internal sources of energy provided by an attached active filament. The latter is modeled as a chain of chemo-mechanically active beads connected by potentials that enforce semi-flexibility and self-avoidance. The fluid flow produced by the active beads and the forces they mediate are explicitly taken into account in the overdamped equations of motion describing the colloid-filament assembly...
January 14, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28087408/effects-of-loading-concentration-blood-and-synovial-fluid-on-antibiotic-release-and-anti-biofilm-activity-of-bone-cement-beads
#4
Devendra Dusane, Scott Diamond, Cory Knecht, Nicholas Farrar, Casey Peters, Robert Howlin, Matthew Swearingen, Jason Calhoun, Roger D Plaut, Tanya Nocera, Jeffrey Granger, Paul Stoodley
Antibiotic loaded cement beads are commonly used for the treatment of biofilm related orthopaedic periprosthetic infections; however the effects of antibiotic loading and exposure of beads to body fluids on release kinetics are unclear. The purpose of this study was to determine the effects of (i) antibiotic loading density (ii) loading amount (iii) material type and (iv) exposure to body fluids (blood or synovial fluid) on release kinetics and efficacy of antibiotics against planktonic and lawn biofilm bacteria...
January 10, 2017: Journal of Controlled Release: Official Journal of the Controlled Release Society
https://www.readbyqxmd.com/read/28086931/the-release-and-trans-synaptic-transmission-of-tau-via-exosomes
#5
Yipeng Wang, Varun Balaji, Senthilvelrajan Kaniyappan, Lars Krüger, Stephan Irsen, Katharina Tepper, RamReddy Chandupatla, Walter Maetzler, Anja Schneider, Eckhard Mandelkow, Eva-Maria Mandelkow
BACKGROUND: Tau pathology in AD spreads in a hierarchical pattern, whereby it first appears in the entorhinal cortex, then spreads to the hippocampus and later to the surrounding areas. Based on this sequential appearance, AD can be classified into six stages ("Braak stages"). The mechanisms and agents underlying the progression of Tau pathology are a matter of debate. Emerging evidence indicates that the propagation of Tau pathology may be due to the transmission of Tau protein, but the underlying pathways and Tau species are not well understood...
January 13, 2017: Molecular Neurodegeneration
https://www.readbyqxmd.com/read/28081186/mechanical-compression-effects-on-the-secretion-of-vwf-and-il-8-by-cultured-human-vein-endothelium
#6
Dar Weiss, Sharon Avraham, Ruth Guttlieb, Lee Gasner, Alina Lotman, Oren M Rotman, Shmuel Einav
Short peripheral catheters are ubiquitous in today's healthcare environment enabling effective delivery of fluids and medications directly into a patient's vasculature. However, complications related to their use, such as short peripheral catheter thrombophlebitis (SPCT), affect up to 80% of hospitalized patients. While indwelling within the vein, the catheters exert prolonged constant pressure upon the endothelium which can trigger inflammation processes. We have developed and studied an in-vitro model of cultured endothelial cells subjected to mechanical compression of modular self-designed weights, and explored their inflammatory response by quantification of two key biomarkers- vWF and IL-8...
2017: PloS One
https://www.readbyqxmd.com/read/28079888/antiphospholipid-antibodies-enhance-rat-neonatal-cardiomyocyte-apoptosis-in-an-in-vitro-hypoxia-reoxygenation-injury-model-via-p38-mapk
#7
Lauren T Bourke, Thomas McDonnell, James McCormick, Charis Pericleous, Vera M Ripoll, Ian Giles, Anisur Rahman, Anastasis Stephanou, Yiannis Ioannou
A significant amount of myocardial damage during a myocardial infarction (MI) occurs during the reperfusion stage, termed ischaemia/reperfusion (I/R) injury, and accounts for up to 50% of total infarcted tissue post-MI. During the reperfusion phase, a complex interplay of multiple pathways and mechanisms is activated, which ultimately leads to cell death, primarily through apoptosis. There is some evidence from a lupus mouse model that lupus IgG, specifically the antiphospholipid (aPL) antibody subset, is pathogenic in mesenteric I/R injury...
January 12, 2017: Cell Death & Disease
https://www.readbyqxmd.com/read/28079847/relationship-between-abnormalities-on-high-resolution-computerized-tomography-pulmonary-function-and-bronchoalveolar-lavage-in-progressive-systemic-sclerosis
#8
Gulfidan Cakmak, Tuba Selcuk Can, Sule Gundogdu, Canan Akman, Hande Ikitimur, Benan Musellim, Gul Ongen
:  Introduction and aim: Progressive systemic sclerosis (pSS) is a multisystemic connective tissue disease characterized by fibrosis of the skin and internal organs including lung. The mechanisms that leads to progressive lung fibrosis in scleroderma remain obscure. In this study, we aimed to investigate the correlation between HRCT findings and patients' clinical and functional status and the degree of alveolitis based on the BAL resultsMaterials and methods: 65 patients with pSS were evaluated...
December 23, 2016: Sarcoidosis, Vasculitis, and Diffuse Lung Diseases: Official Journal of WASOG
https://www.readbyqxmd.com/read/28079507/do-micrornas-have-a-key-epigenetic-role-in-osteoarthritis-and-in-mechanotransduction
#9
REVIEW
Anna De Palma, Sara Cheleschi, Nicola Antonio Pascarelli, Sara Tenti, Mauro Galeazzi, Antonella Fioravanti
Osteoarthritis (OA) is the most common degenerative disease affecting joint tissues. The pathogenesis of OA is complex and poorly understood, as well as the multiple factors contributing to its development and progression. Accumulating evidence has suggested that microRNAs (miRNAs) play an important role as regulators of cartilage biology and in the pathogenesis of OA. It has been demonstrated that mechanical loading, important for the regulation of cartilage metabolism, affects miRNAs expression. Furthermore, miRNAs present in human plasma and in synovial fluid could represent promising biological markers for OA...
January 4, 2017: Clinical and Experimental Rheumatology
https://www.readbyqxmd.com/read/28078337/a-solvable-model-of-axisymmetric-and-non-axisymmetric-droplet-bouncing
#10
Matthew Andrew, Julia M Yeomans, Dmitri O Pushkin
We introduce a solvable Lagrangian model for droplet bouncing. The model predicts that, for an axisymmetric drop, the contact time decreases to a constant value with increasing Weber number, in qualitative agreement with experiments, because the system is well approximated as a simple harmonic oscillator. We introduce asymmetries in the velocity, initial droplet shape, and contact line drag acting on the droplet and show that asymmetry can often lead to a reduced contact time and lift-off in an elongated shape...
January 12, 2017: Soft Matter
https://www.readbyqxmd.com/read/28077531/sodium-bicarbonate-does-not-prevent-postoperative-acute-kidney-injury-after-off-pump-coronary-revascularization-a-double-blinded-randomized-controlled-trial
#11
S Soh, J W Song, J K Shim, J H Kim, Y L Kwak
BACKGROUND: Acute kidney injury (AKI) is a common morbidity after off-pump coronary revascularization. We investigated whether perioperative administration of sodium bicarbonate, which might reduce renal injury by alleviating oxidative stress in renal tubules, prevents postoperative AKI in off-pump coronary revascularization patients having renal risk factors. METHODS: Patients (n=162) having at least one of the following AKI risk factors were enrolled: (i) age >70 yr; (ii) diabetes mellitus; (iii) chronic renal disease; (iv) congestive heart failure or left ventricular ejection fraction <35%; and (v) reoperation or emergency...
October 2016: British Journal of Anaesthesia
https://www.readbyqxmd.com/read/28075157/visual-occlusion-during-minimally-invasive-surgery-a-contemporary-review-of-methods-to-reduce-laparoscopic-and-robotic-lens-fogging-and-other-sources-of-optical-loss
#12
Todd Galvin Manning, Marlon Perera, Daniel Christidis, Ned Kinnear, Shannon McGrath, Richard O'Beirne, Paul Zotov, Damien M Bolton, Nathan Lawrentschuk
Background Maintenance of optimal vision during minimally invasive surgery is crucial to maintaining operative awareness, efficiency and safety. Hampered vision is commonly caused by laparoscopic lens fogging (LLF) which has prompted the development of various anti-fogging fluids and warming devices. However, limited comparative evidence exists in contemporary literature. Despite technological advancements there remains no consensus as to superior methods to prevent LLF or restore visual acuity once LLF has occurred...
January 11, 2017: Journal of Endourology
https://www.readbyqxmd.com/read/28074940/alpha7-nicotinic-acetylcholine-receptor-is-required-for-amyloid-pathology-in-brain-endothelial-cells-induced-by-glycoprotein-120-methamphetamine-and-nicotine
#13
Liqun Liu, Jingyi Yu, Li Li, Bao Zhang, Lingjuan Liu, Chun-Hua Wu, Ambrose Jong, Ding-An Mao, Sheng-He Huang
One of the most challenging issues in HIV-associated neurocognitive disorders (HAND) caused by HIV-1 virotoxins and drug abuse is the lack of understanding the underlying mechanisms that are commonly associated with disorders of the blood-brain barrier (BBB), which mainly consists of brain microvascular endothelial cells (BMEC). Here, we hypothesized that Glycoprotein 120 (gp120), methamphetamine (METH) and nicotine (NT) can enhance amyloid-beta (Aβ) accumulation in BMEC through Alpha7 nicotinic acetylcholine receptor (α7 nAChR)...
January 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28074878/microscopic-evolution-of-laboratory-volcanic-hybrid-earthquakes
#14
H O Ghaffari, W A Griffith, P M Benson
Characterizing the interaction between fluids and microscopic defects is one of the long-standing challenges in understanding a broad range of cracking processes, in part because they are so difficult to study experimentally. We address this issue by reexamining records of emitted acoustic phonon events during rock mechanics experiments under wet and dry conditions. The frequency spectrum of these events provides direct information regarding the state of the system. Such events are typically subdivided into high frequency (HF) and low frequency (LF) events, whereas intermediate "Hybrid" events, have HF onsets followed by LF ringing...
January 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28074541/comparison-of-respiratory-motion-suppression-techniques-for-4d-flow-mri
#15
Petter Dyverfeldt, Tino Ebbers
PURPOSE: The purpose of this work was to assess the impact of respiratory motion and to compare methods for suppression of respiratory motion artifacts in 4D Flow MRI. METHODS: A numerical 3D aorta phantom was designed based on an aorta velocity field obtained by computational fluid mechanics. Motion-distorted 4D Flow MRI measurements were simulated and several different motion-suppression techniques were evaluated: Gating with fixed acceptance window size, gating with different window sizes in inner and outer k-space, and k-space reordering...
January 11, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/28074401/adipsic-diabetes-insipidus-in-adult-patients
#16
REVIEW
Martín Cuesta, Mark J Hannon, Christopher J Thompson
INTRODUCTION: Adipsic diabetes insipidus (ADI) is a very rare disorder, characterized by hypotonic polyuria due to arginine vasopressin (AVP) deficiency and failure to generate the sensation of thirst in response to hypernatraemia. As the sensation of thirst is the key homeostatic mechanism that prevents hypernatraemic dehydration in patients with untreated diabetes insipidus (DI), adipsia leads to failure to respond to aquaresis with appropriate fluid intake. This predisposes to the development of significant hypernatraemia, which is the typical biochemical manifestation of adipsic DI...
January 10, 2017: Pituitary
https://www.readbyqxmd.com/read/28074342/the-presence-of-modified-nucleosides-in-extracellular-fluids-leads-to-the-specific-incorporation-of-5-chlorocytidine-into-rna-and-modulates-the-transcription-and-translation
#17
Caroline Noyon, Thierry Roumeguère, Cédric Delporte, Damien Dufour, Melissa Cortese, Jean-Marc Desmet, Christophe Lelubre, Alexandre Rousseau, Philippe Poelvoorde, Jean Nève, Luc Vanhamme, Karim Zouaoui Boudjeltia, Pierre Van Antwerpen
Myeloperoxidase (MPO) is able to promote several kinds of damage and is involved in mechanisms leading to various diseases such as atherosclerosis or cancers. An example of these damages is the chlorination of nucleic acids, which is considered as a specific marker of the MPO activity. Since 5-chlorocytidine has been recently shown in healthy donor plasmas, this study aimed at discovering if these circulating modified nucleosides could be incorporated into RNA and DNA and if their presence impacts the ability of enzymes involved in the incorporation, transcription, and translation processes...
January 10, 2017: Molecular and Cellular Biochemistry
https://www.readbyqxmd.com/read/28073075/freeform-extrusion-fabrication-of-titanium-fiber-reinforced-13-93-bioactive-glass-scaffolds
#18
Albin Thomas, Krishna C R Kolan, Ming C Leu, Gregory E Hilmas
Although implants made with bioactive glass have shown promising results for bone repair, their application in repairing load-bearing long bone is limited due to their poor mechanical properties in comparison to human bone. This work investigates the freeform extrusion fabrication of bioactive silicate 13-93 glass scaffolds reinforced with titanium (Ti) fibers. A composite paste prepared with 13-93 glass and Ti fibers (~16µm in diameter and lengths varying from ~200µm to ~2 mm) was extruded through a nozzle to fabricate scaffolds (0-90° filament orientation pattern) on a heated plate...
December 31, 2016: Journal of the Mechanical Behavior of Biomedical Materials
https://www.readbyqxmd.com/read/28072927/artificial-induction-of-native-aquaporin-1-expression-in-human-salivary-cells
#19
Z Wang, S Pradhan-Bhatt, M C Farach-Carson, M J Passineau
Gene therapy for dry mouth disorders has transitioned in recent years from theoretical to clinical proof of principle with the publication of a first-in-man phase I/II dose escalation clinical trial in patients with radiation-induced xerostomia. This trial used a prototype adenoviral vector to express aquaporin-1 (AQP1), presumably in the ductal cell layer and/or in surviving acinar cells, to drive transcellular flux of interstitial fluid into the labyrinth of the salivary duct. As the development of this promising gene therapy continues, safety considerations are a high priority, particularly those that remove nonhuman agents (i...
January 1, 2017: Journal of Dental Research
https://www.readbyqxmd.com/read/28072601/risk-factors-and-clinical-outcomes-associated-with-perioperative-transfusion-associated-circulatory-overload
#20
Leanne Clifford, Qing Jia, Arun Subramanian, Hemang Yadav, Darrell R Schroeder, Daryl J Kor
BACKGROUND: Transfusion-associated circulatory overload remains underappreciated in the perioperative environment. The authors aimed to characterize risk factors for perioperative transfusion-associated circulatory overload and better understand its impact on patient-important outcomes. METHODS: In this case-control study, 163 adults undergoing noncardiac surgery who developed perioperative transfusion-associated circulatory overload were matched with 726 transfused controls who did not develop respiratory complications...
January 10, 2017: Anesthesiology
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