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https://www.readbyqxmd.com/read/28817821/endoscopic-lung-volume-reduction-an-expert-panel-recommendation-update-2017
#1
Felix J F Herth, Dirk-Jan Slebos, Gerard J Criner, Pallav L Shah
Interest in endoscopic lung volume reduction (ELVR) technologies for emphysema is consistently growing. In the last couple of months, several endoscopic options (e.g., endo- or intrabronchial valves, coil implants, and thermal vapor ablation) that have been evaluated in randomized controlled trials have been reported with the ultimate goal of improving respiratory mechanics and alleviating chronic dyspnea. Patients presenting with severe air trapping and thoracic hyperinflation have the greatest potential to derive benefit from ELVR procedures...
August 18, 2017: Respiration; International Review of Thoracic Diseases
https://www.readbyqxmd.com/read/28817398/three-dimensional-echocardiography-diagnosis-of-double-perforation-of-bicuspid-aortic-valve
#2
Luca Longobardo, Valentina Coluccia, Alessia Azzu, Iside S Scarfò, Ottavio Alfieri, Giovanni La Canna
: Leaflet perforation is a frequently underdiagnosed mechanism of aortic regurgitation, often underdiagnosed by two-dimensional echocardiography. Three-dimensional echocardiography allows a detailed assessment of cusp anatomy, improving diagnosis compared with two-dimensional echo.
August 16, 2017: Journal of Cardiovascular Medicine
https://www.readbyqxmd.com/read/28814849/tiotropium-bromide-exerts-anti-inflammatory-effects-during-resistive-breathing-an-experimental-model-of-severe-airway-obstruction
#3
Dimitrios Toumpanakis, Konstantinos Loverdos, Vassiliki Tzouda, Vyronia Vassilakopoulou, Eleni Litsiou, Christina Magkou, Vassiliki Karavana, Michael Pieper, Theodoros Vassilakopoulos
INTRODUCTION: Resistive breathing (RB), a hallmark of obstructive airway diseases, is characterized by strenuous contractions of the inspiratory muscles that impose increased mechanical stress on the lung. RB is shown to induce pulmonary inflammation in previous healthy animals. Tiotropium bromide, an anticholinergic bronchodilator, is also shown to exert anti-inflammatory effects. The effect of tiotropium on RB-induced pulmonary inflammation is unknown. METHODS: Adult rats were anesthetized, tracheostomized and breathed spontaneously through a two-way non-rebreathing valve...
2017: International Journal of Chronic Obstructive Pulmonary Disease
https://www.readbyqxmd.com/read/28812017/valve-calcification-in-aortic-stenosis-etiology-and-diagnostic-imaging-techniques
#4
REVIEW
María Manuela Izquierdo-Gómez, Iván Hernández-Betancor, Javier García-Niebla, Belén Marí-López, Ignacio Laynez-Cerdeña, Juan Lacalzada-Almeida
Aortic stenosis is the most common valvulopathy in the Western world. Its prevalence has increased significantly in recent years due to population aging; hence, up to 8% of westerners above the age of 84 now have severe aortic stenosis (Lindroos et al., 1993). This causes increased morbidity and mortality and therein lies the importance of adequate diagnosis and stratification of the degree of severity which allows planning the best therapeutic option in each case. Long understood as a passive age-related degenerative process, it is now considered a rather more complex entity involving mechanisms and factors similar to those of atherosclerosis (Stewart et al...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28808575/reduced-ventilation-perfusion-v-q-mismatch-following-endobronchial-valve-insertion-demonstrated-by-gallium-68-v-q-photon-emission-tomography-computed-tomography
#5
Paul Leong, Pierre-Yves Le Roux, Jason Callahan, Shankar Siva, Michael S Hofman, Daniel P Steinfort
Endobronchial valves (EBVs) are increasingly deployed in the management of severe emphysema. Initial studies focussed on volume reduction as the mechanism, with subsequent improvement in forced expiratory volume in 1 s (FEV1). More recent studies have emphasized importance of perfusion on predicting outcomes, though findings have been inconsistent. Gallium-68 ventilation-perfusion (V/Q) photon emission tomography (PET)/computed tomography (CT) is a novel imaging modality with advantages in spatial resolution, quantitation, and speed over conventional V/Q scintigraphy...
September 2017: Respirology Case Reports
https://www.readbyqxmd.com/read/28806488/serotonergic-5-ht2b-receptors-in-mitral-valvulopathy-bone-marrow-mobilization-of-endothelial-progenitors
#6
Estelle Ayme-Dietrich, Roland Lawson, Francine Côté, Claudia de Tapia, Sylvia Da Silva, Claudine Ebel, Béatrice Hechler, Christian Gachet, Jérome Guyonnet, Hélène Rouillard, Jordane Stoltz, Emily Quentin, Sophie Banas, François Daubeuf, Nelly Frossard, Bernard Gasser, Jean-Philippe Mazzucotelli, Olivier Hermine, Luc Maroteaux, Laurent Monassier
BACKGROUND: Valvular heart disease is highly prevalent in industrialized countries. Chronic use of anorexigens, amphetamine or ergot derivatives targeting the serotonin system has been associated with valvular heart disease. PURPOSE AND EXPERIMENTAL APPROACH: Here, we investigated the contribution of serotonin receptors in a mouse model of valve degeneration induced by nordexfenfluramine, the main metabolite of the anorexigens dexfenfluramine and benfluorex. KEY RESULTS: Chronically activated 5-HT2B receptors by nordexfenfluramine in mice mimicked early steps of mitral valve remodelling attested by increased valve thickness, and cell density in a thick extracellular matrix...
August 14, 2017: British Journal of Pharmacology
https://www.readbyqxmd.com/read/28801824/two-dimensional-capillary-zone-electrophoresis-mass-spectrometry-for-the-characterization-of-intact-monoclonal-antibody-charge-variants-including-deamidation-products
#7
Kevin Jooß, Jens Hühner, Steffen Kiessig, Bernd Moritz, Christian Neusüß
Capillary zone electrophoresis (CZE) is a powerful tool that is progressively being applied for the separation of monoclonal antibody (mAb) charge variants. Mass spectrometry (MS) is the desired detection method concerning identification of mAb variants. In biopharmaceutical applications, there exist optimized and validated electrolyte systems for mAb variant quantification. However, these electrolytes interfere greatly with the electrospray ionization (ESI) process. Here, a heart-cut CZE-CZE-MS setup with an implemented mechanical four-port valve interface was developed that used a generic ε-aminocaproic acid based background electrolyte in the first dimension and acetic acid in the second dimension...
August 12, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28800323/platelet-activation-and-erythrocyte-lysis-during-brief-exposure-of-blood-to-pathophysiological-shear-stress-in-vitro
#8
Suvankar Majumdar, Chetan N Patil, Tammy Ladner-Threadgill, Erica Randolph, Greg W Burgreen, John C Kermode
BACKGROUND: Interaction of von Willebrand factor (VWF) with circulating platelets is the trigger for thrombosis in a region of arterial stenosis. These events are typically studied in vitro under conditions where platelets adhere to a VWF-coated surface. Our approach assesses platelet responses in the absence of adhesion. OBJECTIVE: To characterize extent of platelet activation and erythrocyte lysis in an artificial stenosis model. METHODS: Whole blood is perfused through a length of polyetheretherketone tubing that includes an artificial stenosis, comprising narrow-bore (89-381 μm) tubing...
August 11, 2017: Clinical Hemorheology and Microcirculation
https://www.readbyqxmd.com/read/28799251/comparison-of-anticoagulation-regimens-for-pregnant-women-with-prosthetic-heart-valves-a-meta-analysis-of-prospective-studies
#9
Jing Wang, Kangqi Li, Hongyan Li, Weiwei Zhu, Haiyan Sun, Congxiao Lu
INTRODUCTION: Pregnancy is associated with a hypercoagulable state, which makes pregnant women with prosthetic heart valves at high risk of thromboembolism. Proper anticoagulation regimen should take both the maternal protection and the fetal outcomes into consideration. However, no consensus on the present anticoagulation regimen for those women has been reached yet, especially in the first trimester of pregnancy. AIMS: The present meta-analysis is conducted to compare anticoagulation efficiency and feto-maternal complications of heparin and warfarin in the first trimester...
August 11, 2017: Cardiovascular Therapeutics
https://www.readbyqxmd.com/read/28797741/modelling-and-simulation-of-flow-and-agglomeration-in-deep-veins-valves-using-discrete-multi-physics
#10
M Ariane, W Wen, D Vigolo, A Brill, F G B Nash, M Barigou, A Alexiadis
The hemodynamics in flexible deep veins valves is modelled by means of discrete multi-physics and an agglomeration algorithm is implemented to account for blood accrual in the flow. Computer simulations of a number of valves typologies are carried out. The results show that the rigidity and the length of the valve leaflets play a crucial role on both mechanical stress and stagnation in the flow. Rigid and short membranes may be inefficient in preventing blood reflux, but reduce the volume of stagnant blood potentially lowering the chances of thrombosis...
July 29, 2017: Computers in Biology and Medicine
https://www.readbyqxmd.com/read/28795480/hospital-teaching-status-and-trascatheter-aortic-valve-replacement-outcomes-in-the-united-states-analysis-of-the-national-inpatient-sample
#11
Tesfaye Telila, Emmanuel Akintoye, Tomo Ando, Obsinet Merid, Mohan Palla, Sagar Mallikethi-Reddy, Alexandros Briasoulis, Cindy Grines, Luis Afonso
BACKGROUND: Evidence suggests that medical service offerings vary by hospital teaching status. However, little is known about how these translate to patient outcomes. We therefore sought to evaluate this gap in knowledge in patients undergoing Transcatheter aortic valve replacement (TAVR) in the United States. METHODS: This study was conducted using the National Inpatient Sample (NIS) in the United States from 2011 to 2014. Teaching status was classified, as teaching vs...
August 10, 2017: Catheterization and Cardiovascular Interventions
https://www.readbyqxmd.com/read/28795446/tricuspid-valve-replacement-with-mechanical-prostheses-short-and-long-term-outcomes
#12
Xavier Rossello, Christian Muñoz-Guijosa, Elisabet Mena, Marta Camprecios, Ana B Mendez, Xavier Borras, Josep M Padro
BACKGROUND AND AIM: Tricuspid valve replacement has been associated with high mortality and poor long-term outcomes. We report the preoperative risk factors associated with short and long-term outcomes following tricuspid valve replacement with mechanical prostheses. METHODS: In 62 patients who underwent mechanical tricuspid valve replacement, clinical, laboratory, and echocardiographic findings were analyzed using both univariate and multivariate analyses to describe operative and long-term mortality...
August 9, 2017: Journal of Cardiac Surgery
https://www.readbyqxmd.com/read/28792711/differential-expression-of-micrornas-in-calcific-aortic-stenosis
#13
Hai-Xia Xu, Yan Wang, Dong-Dong Zheng, Teng Wang, Min Pan, Jia-Hai Shi, Jian-Hua Zhu, Xiao-Fei Li
BACKGROUND: Calcific aortic stenosis (CAS) is the most common heart valve disorder. To explore the underlying mechanisms, we investigated whether key microRNAs in calcified aortic valves are differentially expressed compared to those in the non-calcified valves. METHODS: Calcified aortic valves from patients with aortic stenosis and non-calcified aortic valves (control) from patients with aortic insufficiency (n = 8 per group) were obtained during cardiac valve replacement surgery...
July 1, 2017: Clinical Laboratory
https://www.readbyqxmd.com/read/28790933/mechanisms-of-smooth-muscle-cell-differentiation-are-distinctly-altered-in-thoracic-aortic-aneurysms-associated-with-bicuspid-or-tricuspid-aortic-valves
#14
Elena Ignatieva, Daria Kostina, Olga Irtyuga, Vladimir Uspensky, Alexey Golovkin, Natalia Gavriliuk, Olga Moiseeva, Anna Kostareva, Anna Malashicheva
Cellular and molecular mechanisms of thoracic aortic aneurysm are not clear and therapeutic approaches are mostly absent. Thoracic aortic aneurysm is associated with defective differentiation of smooth muscle cells (SMC) of aortic wall. Bicuspid aortic valve (BAV) comparing to tricuspid aortic valve (TAV) significantly predisposes to a risk of thoracic aortic aneurysms. It has been suggested recently that BAV-associated aortopathies represent a separate pathology comparing to TAV-associated dilations. The only proven candidate gene that has been associated with BAV remains NOTCH1...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/28790014/bmp2-expression-in-the-endocardial-lineage-is-required-for-av-endocardial-cushion-maturation-and-remodeling
#15
Jacob G Saxon, Daniel R Baer, Julie A Barton, Travis Hawkins, Bingruo Wu, Thomas C Trusk, Stephen E Harris, Bin Zhou, Yuji Mishina, Yukiko Sugi
Distal outgrowth, maturation and remodeling of the endocardial cushion mesenchyme in the atrioventricular (AV) canal are the essential morphogenetic events during four-chambered heart formation. Mesenchymalized AV endocardial cushions give rise to the AV valves and the membranous ventricular septum (VS). Failure of these processes results in several human congenital heart defects. Despite this clinical relevance, the mechanisms governing how mesenchymalized AV endocardial cushions mature and remodel into the membranous VS and AV valves have only begun to be elucidated...
August 5, 2017: Developmental Biology
https://www.readbyqxmd.com/read/28782585/weaving-for-heart-valve-tissue-engineering
#16
REVIEW
Albert Liberski, Nadia Ayad, Dorota Wojciechowska, Radoslaw Kot, Duy M P Vo, Dilibaier Aibibu, Gerald Hoffmann, Chokri Cherif, Katharina Grobelny-Mayer, Marek Snycerski, Helmut Goldmann
Weaving is a resourceful technology which offers a large selection of solutions that are readily adaptable for tissue engineering (TE) of artificial heart valves (HV). The different ways that the yarns are interlaced in this technique could be used to produce complex architectures, such as the three-layer architecture of the leaflets. Once the assembly is complete, growth of cells in the scaffold would occur in the orientation of the yarn, enabling the deposition of extra cellular matrixes proteins in an oriented manner...
August 3, 2017: Biotechnology Advances
https://www.readbyqxmd.com/read/28782083/current-challenges-in-translating-tissue-engineered-heart-valves
#17
REVIEW
O M J A Stassen, D E P Muylaert, C V C Bouten, J Hjortnaes
Heart valve disease is a major health burden, treated by either valve repair or valve replacement, depending on the affected valve. Nearly 300,000 valve replacements are performed worldwide per year. Valve replacement is lifesaving, but not without complications. The in situ tissue-engineered heart valve is a promising alternative to current treatments, but the translation of this novel technology to the clinic still faces several challenges. These challenges originate from the variety encountered in the patient population, the conversion of an implant into a living tissue, the highly mechanical nature of the heart valve, the complex homeostatic tissue that has to be reached at the end stage of the regenerating heart valve, and all the biomaterial properties that can be controlled to obtain this tissue...
September 2017: Current Treatment Options in Cardiovascular Medicine
https://www.readbyqxmd.com/read/28780660/update-on-valvular-heart-disease-in-pregnancy
#18
REVIEW
Lucy M Safi, Sarah V Tsiaras
Valvular heart disease in women of childbearing age poses an increased risk of adverse maternal and fetal outcomes, and management in pregnancy can be challenging. Ideally, patients with suspected valvular disease should have preconception counseling by a multidisciplinary team including cardiologists with expertise in pregnancy and a maternal-fetal medicine specialist. Preconception planning should include a cardiac assessment of maternal risk, determination of frequency of surveillance, and a cardiovascular management plan during delivery...
September 2017: Current Treatment Options in Cardiovascular Medicine
https://www.readbyqxmd.com/read/28780576/mechanical-and-surgical-bioprosthetic-valve-thrombosis
#19
REVIEW
Wei Yao Lim, Guy Lloyd, Sanjeev Bhattacharyya
Valve thrombosis can occur in mechanical prosthetic valves and is increasingly recognised in transcatheter and surgically implanted bioprosthetic valves. The risk of thrombosis of mechanical valves is higher in the mitral position compared with aortic position and in older generation valves (ball and cage valves). There is a wide spectrum of presentation from the asymptomatic patient to those with embolic complications or cardiogenic shock. A combination of transthoracic and transesophageal echocardiography is required to assess the haemodynamic effect of thrombosis (valve gradients and area), leaflet motion and thrombus size...
August 5, 2017: Heart: Official Journal of the British Cardiac Society
https://www.readbyqxmd.com/read/28780254/modeling-the-response-of-exogenously-crosslinked-tissue-to-cyclic-loading-the-effects-of-permanent-set
#20
Will Zhang, Michael S Sacks
Bioprosthetic heart valves (BHVs), fabricated from exogenously crosslinked collagenous tissues, remain the most popular heart valve replacement design. However, the life span of BHVs remains limited to 10-15 years, in part because the mechanisms that underlie BHV failure remain poorly understood. Experimental evidence indicates that BHVs undergo significant changes in geometry with in vivo operation, which lead to stress concentrations that can have significant impact on structural damage. These changes do not appear to be due to plastic deformation, as the leaflets only deform in the elastic regime...
July 11, 2017: Journal of the Mechanical Behavior of Biomedical Materials
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