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https://www.readbyqxmd.com/read/28524029/-predictive-value-of-left-ventricular-diastolic-dysfunction-on-mechanical-ventilation-weaning
#1
Hui Wang, Ming Ma, Desheng Chen, Gang Li, Shupeng Wang, Jingen Xia, Jun Duan
OBJECTIVE: To investigate the predictive value of left ventricular diastolic function on mechanical ventilation weaning in patients with left ventricular ejection fraction (LVEF) > 0.50. METHODS: A retrospective case control study was conducted. Sixty-five patients with LVEF > 0.50 undergoing mechanical ventilation for more than 48 hours admitted to surgery intensive care unit (ICU) of China-Japan Friendship Hospital from June 2014 to December 2016 were enrolled...
May 2017: Zhonghua Wei Zhong Bing Ji Jiu Yi Xue
https://www.readbyqxmd.com/read/28523563/assessment-of-endothelial-cell-function-and-physiological-microcirculatory-reserve-by-video-microscopy-using-a-topical-acetylcholine-and-nitroglycerin-challenge
#2
Matthias Peter Hilty, Jacqueline Pichler, Bulent Ergin, Urs Hefti, Tobias Michael Merz, Can Ince, Marco Maggiorini
BACKGROUND: Assessment of the microcirculation is a promising target for the hemodynamic management of critically ill patients. However, just as the sole reliance on macrocirculatory parameters, single static parameters of the microcirculation may not represent a sufficient guide. Our hypothesis was that by serial topical application of acetylcholine (ACH) and nitroglycerin (NG), the sublingual microcirculation can be challenged to determine its endothelial cell-dependent and smooth muscle-dependent physiological reserve capacity...
December 2017: Intensive Care Medicine Experimental
https://www.readbyqxmd.com/read/28522757/functional-assessment-of-the-diaphragm-by-speckle-tracking-ultrasound-during-inspiratory-loading
#3
Eline Oppersma, Nima Hatam, Jonne Doorduin, Johannes G van der Hoeven, Gernot Marx, Andreas Goetzenich, Sebastian Fritsch, Leo M A Heunks, Christian S Bruells
BACKGROUND: Assessment of diaphragmatic effort is challenging especially in critically ill patients in the phase of weaning. Fractional thickening during inspiration assessed by ultrasound has been used to estimate diaphragm effort. It is unknown whether more sophisticated ultrasound techniques such as speckle tracking are superior in the quantification of inspiratory effort. This study evaluates the validity of speckle tracking ultrasound to quantify diaphragm contractility. METHODS: Thirteen healthy volunteers underwent a randomized stepwise threshold loading protocol of 0 to 50% of the maximal inspiratory pressure...
May 18, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/28507101/human-myosin-viia-is-a-very-slow-processive-motor-protein-on-various-cellular-actin-structures
#4
Osamu Sato, Satoshi Komatsu, Tsuyoshi Sakai, Yoshikazu Tsukasaki, Ryosuke Tanaka, Takeomi Mizutani, Tomonobu M Watanabe, Reiko Ikebe, Mitsuo Ikebe
Human myosin VIIa (MYO7A) is an actin-linked motor protein associated with human Usher syndrome (USH) type 1B, which causes human congenital hearing and visual loss. While it has been thought that the role of human myosin VIIa is critical for USH1 protein tethering with actin and transportation along actin bundles in inner-ear hair cells, myosin VIIa's motor function remains unclear. Here, we studied the motor function of the tail-truncated human myosin VIIa dimer (HM7AΔTail/LZ) at the single-molecule level...
May 15, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28505975/reduced-cardiovascular-functions-in%C3%A2-patients-with-alzheimer-s-disease
#5
Wang-Sheng Jin, Xian-Le Bu, Ye-Ran Wang, Ling Li, Wei-Wei Li, Yu-Hui Liu, Chi Zhu, Xiu-Qing Yao, Yang Chen, Chang-Yue Gao, Tao Zhang, Chang-Yue Gao, Hua-Dong Zhou, Fan Zeng, Yan-Jiang Wang
Previous studies have suggested that cardiovascular functions might play a critical role in Alzheimer's disease (AD) pathogenesis. However, the relationship among heart function, blood flow of cerebral vessels, and AD remains unclear. In the present study, AD patients (n = 34) and age- and gender-matched cognitively normal controls (n = 34) were recruited. Comorbidity information was collected. The ejection fraction was measured using echocardiography, and the mean velocity, pulsatility index (PI), and resistance index (RI) of the basilar artery (BA), left terminal internal carotid artery (LTICA), and right terminal internal carotid artery (RTICA) were measured using transcranial Doppler...
May 11, 2017: Journal of Alzheimer's Disease: JAD
https://www.readbyqxmd.com/read/28505884/experimental-studies-on-combustion-of-composite-biomass-pellets-in-fluidized-bed
#6
Feihong Guo, Zhaoping Zhong
This work presents studies on the combustion of Composite Biomass Pellets (CBPS) in fluidized bed using bauxite particles as the bed material. Prior to the combustion experiment, cold-flow characterization and thermogravimetric analysis are performed to investigate the effect of air velocity and combustion mechanism of CBPS. The cold-state test shows that CBPs and bauxite particles fluidize well in the fluidized bed. However, because of the presence of large CBPs, optimization of the fluidization velocity is rather challenging...
May 11, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28505089/squeeze-film-air-damping-of-a-five-axis-electrostatic-bearing-for-rotary-micromotors
#7
Shunyue Wang, Fengtian Han, Boqian Sun, Haixia Li
Air-film damping, which dominates over other losses, plays a significant role in the dynamic response of many micro-fabricated devices with a movable mass suspended by various bearing mechanisms. Modeling the damping characteristics accurately will be greatly helpful to the bearing design, control, and test in various micromotor devices. This paper presents the simulated and experimental squeeze-film air damping results of an electrostatic bearing for use in a rotary high-speed micromotor. It is shown that the boundary condition to solve the three-dimensional Reynolds equation, which governs the squeeze-film damping in the air gap between the rotor and its surrounding stator sealed in a three-layer evacuated cavity, behaves with strong cross-axis coupling characteristics...
May 13, 2017: Sensors
https://www.readbyqxmd.com/read/28504290/effect-of-body-deformability-on-microswimming
#8
Jayant Pande, Laura Merchant, Timm Krüger, Jens Harting, Ana-Sunčana Smith
In this work we consider the following question: given a mechanical microswimming mechanism, does increased deformability of the swimmer body hinder or promote the motility of the swimmer? To answer this we run immersed-boundary-lattice-Boltzmann simulations of a microswimmer composed of deformable beads connected with springs. We find that the same deformations in the beads can result in different effects on the swimming velocity, namely an enhancement or a reduction, depending on the other parameters. To understand this we determine analytically the velocity of the swimmer, starting from the forces driving the motion and assuming that the deformations in the beads are known as functions of time and are much smaller than the beads themselves...
May 15, 2017: Soft Matter
https://www.readbyqxmd.com/read/28500954/finger-forces-in-fastball-baseball-pitching
#9
Hiroshi Kinoshita, Satoshi Obata, Daiki Nasu, Koji Kadota, Tomoyuki Matsuo, Glenn S Fleisig
Forces imparted by the fingers onto a baseball are the final, critical aspects for pitching, however these forces have not been quantified previously as no biomechanical technology was available. In this study, an instrumented baseball was developed for direct measurement of ball reaction force by individual fingers and used to provide fundamental information on the forces during a fastball pitch. A tri-axial force transducer with a cable having an easily-detachable connector were installed in an official baseball...
May 10, 2017: Human Movement Science
https://www.readbyqxmd.com/read/28498040/pivotal-role-of-non-cardiomyocytes-in-electromechanical-and-therapeutic-potential-of-induced-pluripotent-stem-cell-derived-engineered-cardiac-tissue
#10
Hiroko Iseoka, Shigeru Miyagawa, Satsuki Fukushima, Atsuhiro Saito, Shigeo Masuda, Shin Yajima, Emiko Ito, Nagako Sougawa, Maki Takeda, Akima Harada, Jong-Kook Lee, Yoshiki Sawa
Although engineered cardiac tissues (ECTs) derived from induced pluripotent stem cells (iPSCs) are promising for myocardial regenerative therapy, the appropriate ratio of cardiomyocytes to non-cardiomyocytes is not fully understood. Here, we determined whether ECT-cell content is a key determinant of its structure/function, thereby affecting ECT therapeutic potential for advanced heart failure. Scaffold-free ECTs containing different ratios (25%, 50%, 70%, or 90%) of iPSC-derived cardiomyocytes were generated by magnetic-activated cell sorting using cardiac-specific markers...
May 12, 2017: Tissue Engineering. Part A
https://www.readbyqxmd.com/read/28485943/following-or-against-topographic-wettability-gradient-movements-of-droplets-on-micropatterned-surface
#11
Jiayi Zhao, Shuo Chen
Two kinds of possible movements of droplets (i.e. following or against topographic wettability gradient) on a micropatterned surface are investigated by using a particle-based method, many-body dissipative particle dynamics (MDPD). The displacement along wettability gradient and contact angles on both sides of the droplet are analyzed. The results show that the migration trajectory of the droplet is determined by coexistence of Cassie and Wenzel state, and unbalanced Young's force which are related to impact velocity, pillar height and surface tension etc...
May 9, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28485321/monitoring-changes-in-hepatic-venous-velocities-flow-after-a-fluid-challenge-can-identify-shock-patients-who-lack-fluid-responsiveness
#12
Wei Du, Xiao-Ting Wang, Yun Long, Da-Wei Liu
BACKGROUND: Evaluating the hemodynamic status and predicting fluid responsiveness are important in critical ultrasound assessment of shock patients. Transthoracic echocardiography with noninvasive diagnostic parameters allows the assessment of volume responsiveness. This study aimed to assess the hemodynamic changes in the liver and systemic hemodynamic changes during fluid challenge and during passive leg raising (PLR) by measuring hepatic venous flow (HVF) velocity. METHODS: This is an open-label study in a tertiary teaching hospital...
May 20, 2017: Chinese Medical Journal
https://www.readbyqxmd.com/read/28485316/left-ventricular-longitudinal-systolic-function-in-septic-shock-patients-with-normal-ejection-fraction-a-case-control-study
#13
Hong-Min Zhang, Xiao-Ting Wang, Li-Na Zhang, Wei He, Qing Zhang, Da-Wei Liu
BACKGROUND: Septic cardiomyopathy is a common finding in septic shock patients. The accepted definition of septic cardiomyopathy is often based on the left ventricular ejection fraction (LVEF). The aim of this study was to determine whether the left ventricular longitudinal systolic function was more sensitive than the LVEF in heart function appraisal of septic shock patients. METHODS: This was a case-control study conducted at a 40-bed Intensive Care Unit (ICU) of Peking Union Medical College Hospital...
May 20, 2017: Chinese Medical Journal
https://www.readbyqxmd.com/read/28479513/epicardial-endocardial-breakthrough-during-stable-atrial-macro-reentry-evidence-from-ultra-high-resolution-three-dimensional-mapping-epicardial-endocardial-breakthrough-in-atrial-macro-reentry
#14
Bhupesh Pathik, Geoffrey Lee, Frédéric Sacher, Michel Haïssaguerre, Pierre Jaïs, Grégoire Massoullié, Nicolas Derval, Prashanthan Sanders, Peter Kistler, Jonathan M Kalman
BACKGROUND: Evidence for epicardial-endocardial breakthrough(EEB) is derived from mapping inferences in patients with AF who may also have focal activations. OBJECTIVES: We investigated whether EEB could be discerned during stable right atrial macro-reentry using high-density high-spatial resolution 3D mapping. METHODS: Macro-reentry was diagnosed using 3D mapping and entrainment. Bipolar maps were reviewed for EEB defined as (i)focal endocardial activation with radial spread unaccounted for by an endocardial wavefront and (ii)present with the same timing on every tachycardia cycle...
May 4, 2017: Heart Rhythm: the Official Journal of the Heart Rhythm Society
https://www.readbyqxmd.com/read/28474195/effects-of-temperature-and-fatigue-on-the-metabolism-and-swimming-capacity-of-juvenile-chinese-sturgeon-acipenser-sinensis
#15
Xi Yuan, Yi-Hong Zhou, Ying-Ping Huang, Wen-Tao Guo, David Johnson, Qing Jiang, Jin-Jie Jing, Zhi-Ying Tu
Chinese sturgeon (Acipenser sinensis) is a critically endangered species. A flume-type respirometer, with video, was used to conduct two consecutive stepped velocity tests at 10, 15, 20, and 25 °C. Extent of recovery was measured after the 60-min recovery period between trials, and the recovery ratio for critical swimming speed (U crit) averaged 91.88% across temperatures. Temperature (T) effects were determined by comparing U crit, oxygen consumption rate (MO 2), and tail beat frequency (TBF) for each temperature...
May 4, 2017: Fish Physiology and Biochemistry
https://www.readbyqxmd.com/read/28470059/enhancement-of-pool-boiling-heat-transfer-using-aligned-silicon-nanowire-arrays
#16
Dong Il Shim, Geehong Choi, Namkyu Lee, Taehwan Kim, Beom Seok Kim, Hyung Hee Cho
Enhancing the critical heat flux (CHF), which is the capacity of heat dissipation, is important to secure high stability in two-phase cooling systems. Coolant supply to a dry hot spot is a major mechanism to prevent surface burn-out for enhancing the CHF. Here, we demonstrate a more ready supply of coolant using aligned silicon nanowires (A-SiNWs), with a high aspect ratio (>10) compared to that of conventional random silicon nanowires (R-SiNWs), which have a disordered arrangement, for additional CHF improvement...
May 12, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28466194/the-role-of-laser-power-and-pullback-velocity-in-the-endovenous-laser-ablation-efficacy-an-experimental-study
#17
N Yu Ignatieva, O L Zakharkina, C V Masayshvili, S V Maximov, V N Bagratashvili, V V Lunin
Endovenous laser ablation is an effective and minimally invasive alternative to surgical removal of incompetent veins. However, many controversies concerning optimal laser parameters usage in this procedure still remain. The purpose of this experimental study was to assess the adequate parameters required for vein wall destruction and to evaluate the role of fiber pullback velocity on vessel wall degradation. Varicose vein segments were treated with 1470-nm diode laser 3 to 9.5 W in power. The fiber moved through the vein at a velocity of 0...
May 2, 2017: Lasers in Medical Science
https://www.readbyqxmd.com/read/28463972/spherical-and-cylindrical-cavity-expansion-models-based-prediction-of-penetration-depths-of-concrete-targets
#18
Xiaochao Jin, Huawei Yang, Xueling Fan, Zhihua Wang, Xuefeng Shu
The cavity expansion theory is most widely used to predict the depth of penetration of concrete targets. The main purpose of this work is to clarify the differences between the spherical and cylindrical cavity expansion models and their scope of application in predicting the penetration depths of concrete targets. The factors that influence the dynamic cavity expansion process of concrete materials were first examined. Based on numerical results, the relationship between expansion pressure and velocity was established...
2017: PloS One
https://www.readbyqxmd.com/read/28445761/live-cell-super-resolution-reveals-f-actin-and-plasma-membrane-dynamics-at-the-t-cell-synapse
#19
George W Ashdown, Garth L Burn, David J Williamson, Elvis Pandžić, Ruby Peters, Michael Holden, Helge Ewers, Lin Shao, Paul W Wiseman, Dylan M Owen
The cortical actin cytoskeleton has been shown to be critical for the reorganization and heterogeneity of plasma membrane components of many cells, including T cells. Building on previous studies at the T cell immunological synapse, we quantitatively assess the structure and dynamics of this meshwork using live-cell superresolution fluorescence microscopy and spatio-temporal image correlation spectroscopy. We show for the first time, to our knowledge, that not only does the dense actin cortex flow in a retrograde fashion toward the synapse center, but the plasma membrane itself shows similar behavior...
April 25, 2017: Biophysical Journal
https://www.readbyqxmd.com/read/28445078/effects-of-high-intensity-interval-training-on-canoeing-performance
#20
Ming-Ta Yang, Mien-Mien Lee, Shu-Ching Hsu, Kuei-Hui Chan
The purpose of this study was to compare the effects of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) utilizing a canoeing ergometer on endurance determinants, as well as aerobic and anaerobic performances among flat-water canoeists. Fourteen well-trained male flat-water canoeists were divided into an HIIT group or an MICT group. All subjects performed a continuous graded exercise test (GXT) and three fixed-distance (200, 500, and 1000 m) performance tests on a canoeing ergometer to determine canoeing economy, peak oxygen uptake (VO2peak), and power at VO2peak, and to calculate the critical velocity (CV) and anaerobic work capacity before and after the training programmes...
April 26, 2017: European Journal of Sport Science
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