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https://www.readbyqxmd.com/read/28228405/inhibition-of-romk-blocks-macula-densa-tubuloglomerular-feedback-yet-causes-renal-vasoconstriction-in-anesthetized-rats
#1
Magali Araujo, William J Welch, Xiaoyan Zhou, Kathleen Sullivan, Shawn Walsh, Alexander Pasternak, Christopher S Wilcox
The Na+/K+/2Cl- cotransporter (NKCC2) on the loop of Henle is the site of action of furosemide. Since outer medullary potassium channel (ROMK) inhibitors prevent reabsorption by NKCC2, we tested the hypothesis that ROMK inhibition with a novel, selective ROMK inhibitor (Compound C) blocks tubuloglomerular feedback (TGF) and reduces vascular resistance. Loop perfusion of either ROMK inhibitor or furosemide caused dose-dependent blunting of TGF, but the response to furosemide was 10-fold more sensitive (IC50= 10-6M for furosemide and IC50=10-5M for Compound C)...
February 22, 2017: American Journal of Physiology. Renal Physiology
https://www.readbyqxmd.com/read/28214133/dynamic-hyperinflation-in-patients-with-asthma-and-exercise-induced-bronchoconstriction
#2
Olga Mediano, Raquel Casitas, Carlos Villasante, Elisabet Martínez-Cerón, Raúl Galera, Ester Zamarrón, Francisco García-Río
BACKGROUND: Little is known about the behavior of operative lung volumes during exercise in patients with asthma and exercise-induced bronchoconstriction (EIB). OBJECTIVES: To compare the presence of dynamic hyperinflation (DH) in patients with mild asthma with and without EIB and in healthy individuals and to relate the changes in end-expiratory lung volume (EELV) with postexercise airflow reduction. METHODS: A total of 122 consecutive stable patients (>12 years of age) with mild asthma and 38 controls were studied...
February 14, 2017: Annals of Allergy, Asthma & Immunology
https://www.readbyqxmd.com/read/28202552/airway-dynamics-in-copd-patients-by-within-breath-impedance-tracking-effects-of-continuous-positive-airway-pressure
#3
András Lorx, Dorottya Czövek, Zoltán Gingl, Gergely Makan, Bence Radics, Dóra Bartusek, Szabolcs Szigeti, János Gál, György Losonczy, Peter D Sly, Zoltán Hantos
Tracking of the within-breath changes of respiratory mechanics using the forced oscillation technique may provide outcomes that characterise the dynamic behaviour of the airways during normal breathing.We measured respiratory resistance (Rrs) and reactance (Xrs) at 8 Hz in 55 chronic obstructive pulmonary disease (COPD) patients and 20 healthy controls, and evaluated Rrs and Xrs as functions of gas flow (V') and volume (V) during normal breathing cycles. In 12 COPD patients, additional measurements were made at continuous positive airway pressure (CPAP) levels of 4, 8, 14 and 20 hPa...
February 2017: European Respiratory Journal: Official Journal of the European Society for Clinical Respiratory Physiology
https://www.readbyqxmd.com/read/28149069/impact-of-yoga-in-a-case-of-vocal-cord-dysfunction-with-dysautonomia
#4
Rozina Wadhwania
A 23-year-old female with a past medical history of gastroesophageal reflux disease presented with shortness of breath induced by exercise and certain odors. She reported the symptoms of autonomic dysfunction including fatigue, chest pain, lightheadedness, headaches, numbness/tingling in the arms and legs, and exercise intolerance. Vital signs were significant for orthostatic intolerance. Volume flow loop in the pulmonary function tests showed a flattening of the inspiratory portion characteristic of vocal cord dysfunction...
January 2017: International Journal of Yoga
https://www.readbyqxmd.com/read/28144465/incidence-rate-of-post-intubation-tracheal-stenosis-in-patients-admitted-to-five-intensive-care-units-in-iran
#5
Roya Farzanegan, Behrooz Farzanegan, Mahdi Zangi, Majid Golestani Eraghi, Shahram Noorbakhsh, Neda Doozandeh Tabarestani, Mohammad Behgam Shadmehr
BACKGROUND: Tracheal stenosis is one of the worst complications associated with endotracheal intubation and it is the most common reason for reconstructive airway surgeries. Due to various local risk factors, the incidence rate of tracheal stenosis may vary in different countries. In order to estimate the incidence rate of post-intubation tracheal stenosis (PITS) in patients admitted to an intensive care unit (ICU), a follow-up study was planned. As there was no similar methodological model in the literature, a feasibility step was also designed to examine the whole project and to enhance the follow-up rate...
September 2016: Iranian Red Crescent Medical Journal
https://www.readbyqxmd.com/read/28105847/compact-ultrahigh-pressure-nanoflow-capillary-liquid-chromatograph
#6
Xiaofeng Zhao, Xiaofeng Xie, Sonika Sharma, Luke T Tolley, Alex Plistil, Hal E Barnett, Martin P Brisbin, Adam C Swensen, John C Price, Paul B Farnsworth, H Dennis Tolley, Stanley D Stearns, Milton L Lee
A compact ultrahigh-pressure nanoflow liquid chromatograph (LC) was developed with the purpose in mind of creating a portable system that could be easily moved to various testing locations or placed in close proximity to other instruments for optimal coupling, such as with mass spectrometry (MS). The system utilized innovative nanoflow pumps integrated with a very low volume stop-flow injector and mixing tee. The system weighed only 5.9 kg (13 lbs) or 4.5 kg (10 lbs) without a controller and could hold up to 1100 bar (16000 psi) of pressure...
January 3, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28047932/tu-h-campus-iep3-02-neurovascular-4d-parametric-imaging-using-co-registration-of-biplane-dsa-sequences-with-3d-vascular-geometry-obtained-from-cone-beam-ct
#7
A Balasubramoniam, D Bednarek, S Rudin, C Ionita
PURPOSE: To create 4D parametric images using biplane Digital Subtraction Angiography (DSA) sequences co-registered with the 3D vascular geometry obtained from Cone Beam-CT (CBCT). METHODS: We investigated a method to derive multiple 4D Parametric Imaging (PI) maps using only one CBCT acquisition. During this procedure a 3D-DSA geometry is stored and used subsequently for all 4D images. Each time a biplane DSA is acquired, we calculate 2D parametric maps of Bolus Arrival Time (BAT), Mean Transit Time (MTT) and Time to Peak (TTP)...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/28043677/pressure-volume-loop-derived-cardiac-indices-during-dobutamine-stress-a-step-towards-understanding-limitations-in-cardiac-output-in-children-with-hypoplastic-left-heart-syndrome
#8
James Wong, Kuberan Pushparajah, Adelaide de Vecchi, Bram Ruijsink, Gerald F Greil, Tarique Hussain, Reza Razavi
BACKGROUND: Children with a single systemic right ventricle, such as in hypoplastic left heart syndrome (HLHS), frequently experience reduced exercise capacity. Elucidating the causes could help with optimising treatment strategies. METHODS: Prospective data from 10 consecutive symptomatic patients with HLHS undergoing clinical cardiac magnetic resonance with catheterisation (XMR) were analysed. Mean age 8.6years (range 3.5-11.6years), mean time since Fontan completion 5...
March 1, 2017: International Journal of Cardiology
https://www.readbyqxmd.com/read/28040707/stridor-secondary-to-a-subglottic-neuroendocrine-tumour
#9
Daniel W Scholfield, S Virk Jagdeep, Paul Stimpson
Large cell neuroendocrine carcinoma is a rare high-grade neuroendocrine neoplasm of the larynx, that exhibits particularly aggressive behaviour. We present a case of a 42-year-old patient with progressive dyspnoea and biphasic stridor, initially treated as asthma and resulting in delayed definitive management. Flow volume loops demonstrated narrowed inspiratory and expiratory flow volume loops. Subsequent CT neck and thorax indicated a mass arising from the subglottis and the patient proceeded to microlaryngoscopy and trans-oral CO2 laser debulking...
December 30, 2016: QJM: Monthly Journal of the Association of Physicians
https://www.readbyqxmd.com/read/28029367/on-the-feasibility-to-conduct-gradient-liquid-chromatography-separations-in-narrow-bore-columns-at-pressures-up-to-2000bar
#10
Ruben De Pauw, Tim Swier, Bart Degreef, Gert Desmet, Ken Broeckhoven
The limits in operating pressures are extended for narrow-bore columns in gradient elution up to 2000bar. As the required pumps for these pressures are incompatible with common chromatographic solvents and are not suitable to apply a mobile phase composition gradient, a mobile phase delivery and injection system is described and experimentally validated which allows to use any possible chromatographic solvent in isocratic and gradient elution. The mobile phase delivery and injection system also allows to perform multiple separations without the need to depressurize the column...
October 6, 2016: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28026740/comparative-hemodynamic-effects-of-contemporary-percutaneous-mechanical-circulatory-support-devices-in-a-porcine-model-of-acute-myocardial-infarction
#11
Brian R Weil, Filip Konecny, Gen Suzuki, Vijay Iyer, John M Canty
OBJECTIVES: The aim of this study was to directly compare the hemodynamic effects of 2 contemporary percutaneous mechanical circulatory support devices in a porcine model of acute myocardial infarction. BACKGROUND: Percutaneous support devices offer the ability to unload the ischemic left ventricle, but the comparative hemodynamic effects of contemporary platforms are unclear. METHODS: Yorkshire swine (mean weight 76 ± 2 kg; n = 7) were instrumented with a left ventricular (LV) pressure-volume (PV) catheter and subjected to a 2-h coronary occlusion...
November 28, 2016: JACC. Cardiovascular Interventions
https://www.readbyqxmd.com/read/27987598/role-of-vessel-to-prosthesis-size-mismatch-in-venous-valve-performance
#12
Wei-Hsin Tien, Xuefeng Zhao, Henry Y Chen, Zachary C Berwick, Joshua F Krieger, Sean Chambers, Dana Dabiri, Ghassan S Kassab
BACKGROUND: Efforts to treat chronic venous insufficiency have focused on the development of prosthetic venous valves. The role of prosthetic valve-to-vessel size matching has not been determined. The purpose of this investigation was to assess the effect of size mismatching on venous valve function and to establish a mismatch limit that affects valve hemodynamic performance and venous wall stress to improve future valve designs and implants. METHODS: Flow dynamics of prosthetic venous valves were studied in vitro using a pulse duplicator flow loop...
January 2017: Journal of Vascular Surgery. Venous and Lymphatic Disorders
https://www.readbyqxmd.com/read/27982272/cardiopulmonary-exercise-test-background-applicability-and-interpretation
#13
Artur Haddad Herdy, Luiz Eduardo Fonteles Ritt, Ricardo Stein, Claudio Gil Soares de Araújo, Mauricio Milani, Romeu Sérgio Meneghelo, Almir Sérgio Ferraz, Carlos Hossri, Antonio Eduardo Monteiro de Almeida, Miguel Morita Fernandes-Silva, Salvador Manoel Serra
Cardiopulmonary exercise test (CPET) has been gaining importance as a method of functional assessment in Brazil and worldwide. In its most frequent applications, CPET consists in applying a gradually increasing intensity exercise until exhaustion or until the appearance of limiting symptoms and/or signs. The following parameters are measured: ventilation; oxygen consumption (VO2); carbon dioxide production (VCO2); and the other variables of conventional exercise testing. In addition, in specific situations, pulse oximetry and flow-volume loops during and after exertion are measured...
November 2016: Arquivos Brasileiros de Cardiologia
https://www.readbyqxmd.com/read/27929571/an-unusual-mediastinal-mass
#14
J Hardy, A R Jeyabalan, N Bhatt, A R Medford
We report a case of a mediastinal mass indenting the left lateral tracheal wall of a 35-year-old male who presented with weight loss, cough and breathlessness. Flow volume loop and thyroid function tests were normal and thyroid peroxidase antibodies were negative. Technetium scintigraphy and positron emission tomography both showed no uptake. Endobronchial ultrasound-guided fine needle aspiration confirmed ectopic mediastinal thyroid tissue. Mediastinal ectopic thyroid tissue is very rare. Most patients are asymptomatic and euthyroid with positive signals on scintigraphy...
June 2016: Journal of the Royal College of Physicians of Edinburgh
https://www.readbyqxmd.com/read/27890535/partial-hepatectomy-hemodynamics-changes-experimental-data-explained-by-closed-loop-lumped-modeling
#15
Chloe Audebert, Mohamed Bekheit, Petru Bucur, Eric Vibert, Irene E Vignon-Clementel
The liver function may be degraded after partial liver ablation surgery. Adverse liver hemodynamics have been shown to be associated to liver failure. The link between these hemodynamics changes and ablation size is however poorly understood. This article proposes to explain with a closed-loop lumped model the hemodynamics changes observed during twelve surgeries in pigs. The portal venous tree is modeled with a pressure-dependent variable resistor. The variables measured, before liver ablation, are used to tune the model parameters...
January 4, 2017: Journal of Biomechanics
https://www.readbyqxmd.com/read/27865733/systolic-and-diastolic-unloading-by-mechanical-support-of-the-acute-vs-the-chronic-pressure-overloaded-right-ventricle
#16
Tom Verbelen, Daniel Burkhoff, Keiichiro Kasama, Marion Delcroix, Filip Rega, Bart Meyns
BACKGROUND: Right ventricular (RV) mechanical support is well described in cases of sudden increase in RV afterload. In cases of chronic RV pressure overload (e.g., pulmonary arterial hypertension), it has rarely been described. METHODS: The pulmonary artery was banded in 18 sheep. In the acute group (n = 9), we immediately implanted a Synergy Pocket Micro-Pump. Blood was withdrawn from the right atrium to the pulmonary artery. In the chronic group (n = 9), this pump was implanted 8 weeks after banding...
October 17, 2016: Journal of Heart and Lung Transplantation
https://www.readbyqxmd.com/read/27754715/the-extracellular-c-loop-domain-plays-an-important-role-in-the-cell-adhesion-function-of-aquaporin-0
#17
Yosuke Nakazawa, Mikako Oka, Megumi Funakoshi-Tago, Hiroomi Tamura, Makoto Takehana
PURPOSE: Although aquaporin 0 (AQP0) is a member of the AQP family, it has limited water permeability compared with other members. AQP0 may also have cell adhesion-related functions, but the evidence is still limited. Here, we studied the relationship of AQP0 to cell adhesion and determined the region required for cell adhesion. METHODS: L-cell fibroblasts stably expressing AQP0 or AQP1 (L-AQP0 or L-AQP1) were established. One group of cells was stained with CellTracker Red and cultured into a confluent monolayer, whereas the other group was loaded with CellTracker Blue and seeded over the monolayer...
October 18, 2016: Current Eye Research
https://www.readbyqxmd.com/read/27692152/respiratory-pattern-in-a-fshd-pediatric-population
#18
Federica Trucco, Marina Pedemonte, Chiara Fiorillo, Paola Tacchetti, Giacomo Brisca, Claudio Bruno, Carlo Minetti
Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant inherited disorder characterized by selective weakness of face and upper arms and girdle. Respiratory involvement in FSHD has been described mainly in the most severely affected patients. In this work we tested the respiratory function by spirometry in 12 patients affected by FSHD with onset before 18 years. Spirometry results were correlated with motor involvement and compared to aged matched group of Becker patients. Of note FSHD patients present a peculiar pattern characterized by a flat shape in flow-volume loop...
October 2016: Respiratory Medicine
https://www.readbyqxmd.com/read/27620287/ventilator-related-causes-of-lung-injury-the-mechanical-power
#19
L Gattinoni, T Tonetti, M Cressoni, P Cadringher, P Herrmann, O Moerer, A Protti, M Gotti, C Chiurazzi, E Carlesso, D Chiumello, M Quintel
PURPOSE: We hypothesized that the ventilator-related causes of lung injury may be unified in a single variable: the mechanical power. We assessed whether the mechanical power measured by the pressure-volume loops can be computed from its components: tidal volume (TV)/driving pressure (∆P aw), flow, positive end-expiratory pressure (PEEP), and respiratory rate (RR). If so, the relative contributions of each variable to the mechanical power can be estimated. METHODS: We computed the mechanical power by multiplying each component of the equation of motion by the variation of volume and RR: [Formula: see text]where ∆V is the tidal volume, ELrs is the elastance of the respiratory system, I:E is the inspiratory-to-expiratory time ratio, and R aw is the airway resistance...
October 2016: Intensive Care Medicine
https://www.readbyqxmd.com/read/27600131/protocolized-resuscitation-of-burn-patients
#20
REVIEW
Leopoldo C Cancio, Jose Salinas, George C Kramer
Fluid resuscitation of burn patients is commonly initiated using modified Brooke or Parkland formula. The fluid infusion rate is titrated up or down hourly to maintain adequate urine output and other endpoints. Over-resuscitation leads to morbid complications. Adherence to paper-based protocols, flow sheets, and clinical practice guidelines is associated with decreased fluid resuscitation volumes and complications. Computerized tools assist providers. Although completely autonomous closed-loop control of resuscitation has been demonstrated in animal models of burn shock, the major advantages of open-loop and decision-support systems are identifying trends, enhancing situational awareness, and encouraging burn team communication...
October 2016: Critical Care Clinics
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