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https://www.readbyqxmd.com/read/27913141/acute-lung-injury-and-persistent-small-airway-disease-in-a-rabbit-model-of-chlorine-inhalation
#1
Sadiatu Musah, Connie F Schlueter, David M Humphrey, Karen S Powell, Andrew M Roberts, Gary W Hoyle
Chlorine is a pulmonary toxicant to which humans can be exposed through accidents or intentional releases. Acute effects of chlorine inhalation in humans and animal models have been well characterized, but less is known about persistent effects of acute, high-level chlorine exposures. In particular, animal models that reproduce the long-term effects suggested to occur in humans are lacking. Here, we report the development of a rabbit model in which both acute and persistent effects of chlorine inhalation can be assessed...
November 29, 2016: Toxicology and Applied Pharmacology
https://www.readbyqxmd.com/read/27908351/pim1-kinase-overexpression-enhances-ckit-cardiac-stem-cell-cardiac-repair-following-myocardial-infarction-in-swine
#2
Shathiyah Kulandavelu, Vasileios Karantalis, Julia Fritsch, Konstantinos E Hatzistergos, Viky Y Loescher, Frederic McCall, Bo Wang, Luiza Bagno, Samuel Golpanian, Ariel Wolf, Justin Grenet, Adam Williams, Aaron Kupin, Aaron Rosenfeld, Sadia Mohsin, Mark A Sussman, Azorides Morales, Wayne Balkan, Joshua M Hare
BACKGROUND: Pim1 kinase plays an important role in cell division, survival, and commitment of precursor cells towards a myocardial lineage, and overexpression of Pim1 in ckit(+) cardiac stem cells (CSCs) enhances their cardioreparative properties. OBJECTIVES: The authors sought to validate the effect of Pim1-modified CSCs in a translationally relevant large animal preclinical model of myocardial infarction (MI). METHODS: Human cardiac stem cells (hCSCs, n = 10), hckit(+) CSCs overexpressing Pim1 (Pim1(+); n = 9), or placebo (n = 10) were delivered by intramyocardial injection to immunosuppressed Yorkshire swine (n = 29) 2 weeks after MI...
December 6, 2016: Journal of the American College of Cardiology
https://www.readbyqxmd.com/read/27902706/a-qualitative-study-of-medical-oncologists-experiences-of-their-profession-and-workforce-sustainability
#3
Alex Broom, W K Tim Wong, Emma Kirby, David Sibbritt, Deme Karikios, Rosemary Harrup, Zarnie Lwin
BACKGROUND: Medical oncology is a steadily evolving field of medical practice and professional pathway for doctors, offering value, opportunity and challenge to those who chose this medical specialty. This study examines the experiences of a group of Australian medical oncologists, with an emphasis on their professional practice, career experiences, and existing and emerging challenges across career stages. METHODS: In-depth qualitative interviews were conducted with 22 medical oncologists, including advanced trainees, early-career consultants and senior consultants, focusing on: professional values and experiences; career prospects and pathways; and, the nexus of the characteristics of the profession and delivery of care...
2016: PloS One
https://www.readbyqxmd.com/read/27891285/complex-perineal-trauma-with-anorectal-avulsion
#4
Adelina Maria Cruceru, Ionut Negoi, Sorin Paun, Sorin Hostiuc, Ruxandra Irina Negoi, Mircea Beuran
Introduction. The objective of this case report is to illustrate a severe perineal impalement injury, associated with anorectal avulsion and hemorrhagic shock. Results. A 32-year-old male patient was referred to our hospital for an impalement perineal trauma, associated with complex pelvic fracture and massive perineal soft tissue destruction and anorectal avulsion. On arrival, the systolic blood pressure was 85 mm Hg and the hemoglobin was 7.1 g/dL. The patient was transported to the operating room, and perineal lavage, hemostasis, and repacking were performed...
2016: Case Reports in Surgery
https://www.readbyqxmd.com/read/27890535/partial-hepatectomy-hemodynamics-changes-experimental-data-explained-by-closed-loop-lumped-modeling
#5
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...
November 16, 2016: 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
#6
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/27855113/comparison-of-novel-physiological-load-adaptive-control-strategies-for-ventricular-assist-devices
#7
Moriz Habigt, Maike Ketelhut, Jonas Gesenhues, Frank Schrödel, Marc Hein, Mare Mechelinck, Thomas Schmitz-Rode, Dirk Abel, Rolf Rossaint
Terminal heart failure (HF) is the most prevalent cause of death in the Western world and the implantation of a left ventricular assist device (LVAD) has become the gold standard therapy today. Most of the actually implanted devices are driven at a constant speed (CS) regardless of the patient's physiological demand. A new physiological controller [power ratio (PR) controller], which keeps a constant ratio between LVAD power and left ventricular power, a previous concept [preload responsive speed (PRS) controller], which adds a variable LVAD power to reach a defined stroke work, and a CS controller were compared with an unimpaired ventricle in a full heart computer simulation model...
November 17, 2016: Biomedizinische Technik. Biomedical Engineering
https://www.readbyqxmd.com/read/27830731/pore-structure-characterization-of-chang-7-tight-sandstone-using-micp-combined-with-n2ga-techniques-and-its-geological-control-factors
#8
Zhe Cao, Guangdi Liu, Hongbin Zhan, Chaozheng Li, Yuan You, Chengyu Yang, Hang Jiang
Understanding the pore networks of unconventional tight reservoirs such as tight sandstones and shales is crucial for extracting oil/gas from such reservoirs. Mercury injection capillary pressure (MICP) and N2 gas adsorption (N2GA) are performed to evaluate pore structure of Chang-7 tight sandstone. Thin section observation, scanning electron microscope, grain size analysis, mineral composition analysis, and porosity measurement are applied to investigate geological control factors of pore structure. Grain size is positively correlated with detrital mineral content and grain size standard deviation while negatively related to clay content...
November 10, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27817156/assessment-of-dexmedetomidine-effects-on-left-ventricular-function-using-pressure-volume-loops-in-rats
#9
Kyuho Lee, Hye Jeong Hwang, Ok Soo Kim, Young Jun Oh
PURPOSE: The role of dexmedetomidine on left ventricular function is ambiguous. We analyzed pressure-volume loops to investigate whether dexmedetomidine has a myocardial depressive effect. METHODS: Thirty-two Sprague-Dawley rats were anesthetized and a pressure-volume loop catheter was advanced into the left ventricle. Rats were divided into four groups (n = 8 each). The control group received a 10-min infusion of 0.1 ml of normal saline, and the other three groups received 1...
November 5, 2016: Journal of Anesthesia
https://www.readbyqxmd.com/read/27797160/pathogenesis-of-central-and-complex-sleep-apnoea
#10
REVIEW
Jeremy E Orr, Atul Malhotra, Scott A Sands
Central sleep apnoea (CSA) - the temporary absence or diminution of ventilatory effort during sleep - is seen in a variety of forms including periodic breathing in infancy and healthy adults at altitude and Cheyne-Stokes respiration in heart failure. In most circumstances, the cyclic absence of effort is paradoxically a consequence of hypersensitive ventilatory chemoreflex responses to oppose changes in airflow, that is elevated loop gain, leading to overshoot/undershoot ventilatory oscillations. Considerable evidence illustrates overlap between CSA and obstructive sleep apnoea (OSA), including elevated loop gain in patients with OSA and the presence of pharyngeal narrowing during central apnoeas...
October 31, 2016: Respirology: Official Journal of the Asian Pacific Society of Respirology
https://www.readbyqxmd.com/read/27776179/3d-real-time-echocardiography-combined-with-mini-pressure-wire-generate-reliable-pressure-volume-loops-in-small-hearts
#11
Ulrike Herberg, Katharina Linden, Oliver Dewald, Eva Gatzweiler, Matthias Seehase, Georg Daniel Duerr, Jonas Dörner, Stephanie Kleppe, Dennis Ladage, Johannes Breuer
BACKGROUND: Pressure-volume loops (PVL) provide vital information regarding ventricular performance and pathophysiology in cardiac disease. Unfortunately, acquisition of PVL by conductance technology is not feasible in neonates and small children due to the available human catheter size and resulting invasiveness. The aim of the study was to validate the accuracy of PVL in small hearts using volume data obtained by real-time three-dimensional echocardiography (3DE) and simultaneously acquired pressure data...
2016: PloS One
https://www.readbyqxmd.com/read/27768034/primary-outcome-assessment-in-a-pig-model-of-acute-myocardial-infarction
#12
Guilielmus H J M Ellenbroek, Gerardus P J van Hout, Leo Timmers, Pieter A Doevendans, Gerard Pasterkamp, Imo E Hoefer
Mortality after acute myocardial infarction remains substantial and is associated with significant morbidity, like heart failure. Novel therapeutics are therefore required to confine cardiac damage, promote survival and reduce the disease burden of heart failure. Large animal experiments are an essential part in the translational process from experimental to clinical therapies. To optimize clinical translation, robust and representative outcome measures are mandatory. The present manuscript aims to address this need by describing the assessment of three clinically relevant outcome modalities in a pig acute myocardial infarction (AMI) model: infarct size in relation to area at risk (IS/AAR) staining, 3-dimensional transesophageal echocardiography (TEE) and admittance-based pressure-volume (PV) loops...
October 14, 2016: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/27756610/promising-approach-for-the-preclinical-assessment-of-cardiac-risks-using-left-ventricular-pressure-volume-loop-analyses-in-anesthetized-monkeys
#13
Tomomichi Ishizaka, Yu Yoshimatsu, Yu Maeda, Wataru Takasaki, Katsuyoshi Chiba, Kazuhiko Mori
INTRODUCTION: Load-independent cardiac parameters obtained from the ventricular pressure-volume relationship are recognized as gold standard indexes for evaluating cardiac inotropy. In this study, for better analyses of cardiac risks, load-independent pressure-volume loop parameters were assessed in addition to load-dependent inotropic, hemodynamic and electrocardiographic changes in isoflurane-anesthetized monkeys. METHODS: The animals were given milrinone (a PDE 3 inhibitor), metoprolol (a β-blocker), or dl-sotalol (a β+IKr blocker) intravenously over 10min at two dose levels including clinically relevant doses (n=5/drug)...
October 15, 2016: Journal of Pharmacological and Toxicological Methods
https://www.readbyqxmd.com/read/27754081/os-19-04-chronic-diuretic-therapy-does-not-impair-the-effectiveness-of-patiromer-in-hyperkalemic-patients-with-ckd
#14
Matthew Weir, Martha Mayo, Dahlia Garza, Susan Arthur, Lance Berman, David Bushinsky, Daniel Wilson, Murray Epstein
OBJECTIVE: Diuretics, alone or in combination, are frequently prescribed in chronic kidney disease (CKD) and heart failure (HF) patients to reduce volume, blood pressure, and/or for symptom control. Clinicians may also use them to reduce the risk of hyperkalemia, but high doses of diuretics may lead to adverse events from intravascular volume depletion or gout. Patiromer is a non-absorbed K-binding polymer recently approved by the FDA for the treatment of hyperkalemia (HK). We compared patiromer's effects in RAASi-treated CKD patients with HK on different types of diuretics to patients not receiving diuretics in the treatment phase of OPAL-HK...
September 2016: Journal of Hypertension
https://www.readbyqxmd.com/read/27754015/br-04-1management-of-treatment-resistant-hypertension
#15
David John Webb
Treatment-resistant hypertension (TRH) is defined as the failure to achieve an office BP target of <140/90 mmHg (<130/80 mmHg in patients with chronic kidney disease (CKD) or diabetes) in patients with hypertension (HT), despite adherence to at least 3 antihypertensive medications at optimal tolerated doses, ideally including a diuretic (Calhoun et al., Circulation 2008). TRH identifies patients with hard-to-treat HT, who might benefit from specialist investigation and treatment. Although some studies put the prevalence of TRH as >10%, these levels may be inflated by white-coat hypertension and poor adherence...
September 2016: Journal of Hypertension
https://www.readbyqxmd.com/read/27746403/activation-of-latent-dihydroorotase-from-aquifex-aeolicus-by-pressure
#16
Guy Herv Eacute, Hedeel Guy Evans, Roshini Fernado, Chandni Patel, Fatme Hachem, David R Evans
Elevated hydrostatic pressure was used to probe conformational changes of Aquifex aeolicus dihydroorotase (DHO) which catalyzes the third step in de novo pyrimidine biosynthesisis. The isolated protein, a 45 kDa monomer, lacks catalytic activity but becomes active upon formation of a dodecameric complex with aspartate transcarbamoylase (ATC). X-ray crystallographic studies of the isolated DHO and of the complex showed that association induces several major conformational changes in the DHO structure. In the isolated DHO, a flexible loop occludes the active site blocking the access of substrates...
October 16, 2016: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/27743468/a-monolithic-3d-0d-coupled-closed-loop-model-of-the-heart-and-the-vascular-system-experiment-based-parameter-estimation-for-patient-specific-cardiac-mechanics
#17
M Hirschvogel, M Bassilious, L Jagschies, S M Wildhirt, M W Gee
A model for patient-specific cardiac mechanics simulation is introduced, incorporating a 3-dimensional finite element model of the ventricular part of the heart which is coupled to a reduced-order 0-dimensional closed-loop vascular system, heart valve and atrial chamber model.The ventricles are modeled by a nonlinear orthotropic passive material law. The electrical activation is mimicked by a prescribed parametrized active stress acting along a generic muscle fiber orientation. Our activation function is constructed such that the start of ventricular contraction and relaxation as well as the active stress curve's slope are parameterized...
October 15, 2016: International Journal for Numerical Methods in Biomedical Engineering
https://www.readbyqxmd.com/read/27707784/improved-patient-selection-for-cardiac-resynchronization-therapy-by-normalization-of-qrs-duration-to-left-ventricular-dimension
#18
A Zweerink, L Wu, G J de Roest, R Nijveldt, C C de Cock, A C van Rossum, C P Allaart
AIMS: This study evaluates the relative importance of two components of QRS prolongation, myocardial conduction velocity and travel distance of the electrical wave front (i.e. path length), for the prediction of acute response to cardiac resynchronization therapy (CRT) in left bundle branch block (LBBB) patients. METHODS: Thirty-two CRT candidates (ejection fraction <35%, LBBB) underwent cardiac magnetic resonance (CMR) imaging to provide detailed information on left ventricular (LV) dimensions...
October 5, 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/27643002/os-19-04-chronic-diuretic-therapy-does-not-impair-the-effectiveness-of-patiromer-in-hyperkalemic-patients-with-ckd
#19
Matthew Weir, Martha Mayo, Dahlia Garza, Susan Arthur, Lance Berman, David Bushinsky, Daniel Wilson, Murray Epstein
OBJECTIVE: Diuretics, alone or in combination, are frequently prescribed in chronic kidney disease (CKD) and heart failure (HF) patients to reduce volume, blood pressure, and/or for symptom control. Clinicians may also use them to reduce the risk of hyperkalemia, but high doses of diuretics may lead to adverse events from intravascular volume depletion or gout. Patiromer is a non-absorbed K-binding polymer recently approved by the FDA for the treatment of hyperkalemia (HK). We compared patiromer's effects in RAASi-treated CKD patients with HK on different types of diuretics to patients not receiving diuretics in the treatment phase of OPAL-HK...
September 2016: Journal of Hypertension
https://www.readbyqxmd.com/read/27642926/br-04-1management-of-treatment-resistant-hypertension
#20
David John Webb
Treatment-resistant hypertension (TRH) is defined as the failure to achieve an office BP target of <140/90 mmHg (<130/80 mmHg in patients with chronic kidney disease (CKD) or diabetes) in patients with hypertension (HT), despite adherence to at least 3 antihypertensive medications at optimal tolerated doses, ideally including a diuretic (Calhoun et al., Circulation 2008). TRH identifies patients with hard-to-treat HT, who might benefit from specialist investigation and treatment. Although some studies put the prevalence of TRH as >10%, these levels may be inflated by white-coat hypertension and poor adherence...
September 2016: Journal of Hypertension
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