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https://www.readbyqxmd.com/read/28092512/a-hidden-markov-model-for-seismocardiography
#1
Johan Wahlstrom, Isaac Skog, Peter Handel, Farzad Khosrow-Khavar, Kouhyar Tavakolian, Phyllis K Stein, Arye Nehorai
We propose a hidden Markov model approach for processing seismocardiograms. The seismocardiogram morphology is learned using the expectation-maximization algorithm, and the state of the heart at a given time instant is estimated by the Viterbi algorithm. From the obtained Viterbi sequence, it is then straightforward to estimate instantaneous heart rate, heart rate variability measures, and cardiac time intervals (the latter requiring a small number of manual annotations). As is shown in the conducted experimental study, the presented algorithm outperforms the state-of-the-art in seismocardiogrambased heart rate and heart rate variability estimation Moreover, the isovolumic contraction time and the left ventricular ejection time are estimated with mean absolute errors of about 5 [ms] and 9 [ms], respectively...
January 9, 2017: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/28092285/perioperative-%C3%AE-blockers-in-patients-undergoing-noncardiac-surgery-scientific-misconduct-and-clinical-guidelines
#2
Dhauna Karam, Rohit Arora
BACKGROUND: β-blocker use in perioperative period of noncardiac surgeries has been a topic of debate since many years. Earlier studies conducted in the 90s showed decreased cardiac adverse events and improved postoperative outcomes with β-blocker use. Based on this, the ACCF and ESC published guidelines strongly supporting β-blocker use. But contemporaneous studies conducted revealed conflicting evidence and have also proven some of the earlier studies to be fraudulent. Although ACCF guidelines have been updated to partially reflect the changes, ESC guidelines continue to support β-blocker use...
January 10, 2017: American Journal of Therapeutics
https://www.readbyqxmd.com/read/28090786/inorganic-nitrite-modulates-mirna-signatures-in-acute-myocardial-in-vivo-ischemia-reperfusion
#3
Ulrike B Hendgen-Cotta, Daniel Messiha, Sonja Esfeld, René Deenen, Tienush Rassaf, Matthias Totzeck
Acute myocardial infarction is the leading cause of mortality in the industrialized world. While it is essential to attempt an early reperfusion of ischemic myocardial territories, reperfusion itself adds damage to the heart, the ischemia-reperfusion (I/R) injury. Particularly the injury resulting from the very first minutes of reperfusion remains incompletely understood. MicroRNAs (miRNAs) are dynamic regulators in I/R injury. Nitric oxide (•NO) signaling, in turn, interacts with miRNA signaling. Our previous investigations showed that •NO signaling in I/R could be modulated by nitrite...
January 16, 2017: Free Radical Research
https://www.readbyqxmd.com/read/28090294/the-effects-of-pulmonary-vasodilating-agents-on-right-ventricular-parameters-in-severe-group-3-pulmonary-hypertension-a-pilot-study
#4
Takahiro Sato, Ichizo Tsujino, Ayako Sugimoto, Toshitaka Nakaya, Taku Watanabe, Hiroshi Ohira, Masaru Suzuki, Satoshi Konno, Noriko Oyama-Manabe, Masaharu Nishimura
Pulmonary arterial hypertension (PAH)-approved vasodilators improve right ventricular (RV) function in patients with PAH. However, whether PAH-approved drugs ameliorate RV morphology and function in lung disease-associated pulmonary hypertension (lung-PH) remains unclear. We aimed to prospectively evaluate the changes in RV volume and ejection fraction (RVEF) in 14 consecutive severe lung-PH patients treated with PAH-approved vasodilators. Severe lung-PH was defined as a mean pulmonary arterial pressure (MPAP) of ≥35 mmHg or an MPAP of ≥25 mmHg with a cardiac index (L/min/m(2)) of <2...
December 2016: Pulmonary Circulation
https://www.readbyqxmd.com/read/28089668/ebio-does-not-induce-cardiomyogenesis-in-human-pluripotent-stem-cells-but-modulates-cardiac-subtype-enrichment-by-lineage-selective-survival
#5
Monica Jara-Avaca, Henning Kempf, Michael Rückert, Diana Robles-Diaz, Annika Franke, Jeanne de la Roche, Martin Fischer, Daniela Malan, Philipp Sasse, Wladimir Solodenko, Gerald Dräger, Andreas Kirschning, Ulrich Martin, Robert Zweigerdt
Subtype-specific human cardiomyocytes (CMs) are valuable for basic and applied research. Induction of cardiomyogenesis and enrichment of nodal-like CMs was described for mouse pluripotent stem cells (mPSCs) in response to 1-ethyl-2-benzimidazolinone (EBIO), a chemical modulator of small-/intermediate-conductance Ca(2+)-activated potassium channels (SKs 1-4). Investigating EBIO in human pluripotent stem cells (PSCs), we have applied three independent differentiation protocols of low to high cardiomyogenic efficiency...
January 4, 2017: Stem Cell Reports
https://www.readbyqxmd.com/read/28089344/heparan-sulfate-storage-in-the-cardiac-conduction-system-triggers-atrioventricular-block
#6
Rie Kato, Hiroaki Miyahara, Tatsuya Kawano, Atsuko Matsuzuka, Kimiko Noda, Tatsuro Izumi
OBJECTIVE: To elucidate the novel biological functions of heparan sulfate (HS) by clinic-pathologically studying a patient with paroxysmal atrioventricular (AV) block. PATIENT: A long-surviving male patient with Sanfilippo syndrome type A presented with paroxysmal AV block at age 33years. He then survived another 2.5years after the onset of paroxysmal AV block and pacemaker implantation. METHODS AND RESULTS: His cardiac histopathological examination at autopsy showed HS storage in the cardiac conduction system (CCS), especially in the atrioventricular node (AVN)-His bundle branches...
January 12, 2017: Brain & Development
https://www.readbyqxmd.com/read/28089252/practical-approaches-for-whole-genome-sequence-analysis-of-heart-and-blood-related-traits
#7
Alanna C Morrison, Zhuoyi Huang, Bing Yu, Ginger Metcalf, Xiaoming Liu, Christie Ballantyne, Josef Coresh, Fuli Yu, Donna Muzny, Elena Feofanova, Navin Rustagi, Richard Gibbs, Eric Boerwinkle
Whole-genome sequencing (WGS) allows for a comprehensive view of the sequence of the human genome. We present and apply integrated methodologic steps for interrogating WGS data to characterize the genetic architecture of 10 heart- and blood-related traits in a sample of 1,860 African Americans. In order to evaluate the contribution of regulatory and non-protein coding regions of the genome, we conducted aggregate tests of rare variation across the entire genomic landscape using a sliding window, complemented by an annotation-based assessment of the genome using predefined regulatory elements and within the first intron of all genes...
January 5, 2017: American Journal of Human Genetics
https://www.readbyqxmd.com/read/28089147/sequent-please-vs-pantera-lux-drug-coated-balloon-angioplasty-in-real-life-results-from-the-d%C3%A3-sseldorf-dcb-registry
#8
Athena Assadi-Schmidt, Annemarie Mohring, Eva Liebsch, Lisa Dannenberg, Alina Achilles, Martin Pöhl, Shazia Afzal, Verena Veulemans, Patrick Horn, Roberto Sansone, Florian Bönner, Bodo Levkau, Malte Kelm, Tobias Zeus, Amin Polzin
BACKGROUND: In-stent restenosis (ISR) is still a major concern in interventional cardiology. Drug coated balloon (DCB) angioplasty has been shown to be a promising option in treatment of ISR. However heterogeneity of different DCBs in suppression of neointimal growth has been described in a porcine model of coronary ISR. Therefore, in this registry analysis, we compared two frequently used paclitaxel eluting DCBs, the SeQuent Please and the Pantera Lux DCB. METHODS: 571 patients were treated with DCB angioplasty at the Heinrich-Heine University Düsseldorf between 2009 and 2012...
December 13, 2016: International Journal of Cardiology
https://www.readbyqxmd.com/read/28088261/parquetina-nigrescens-leaves-chemical-profile-and-influence-on-the-physical-and-biochemical-indices-of-sexual-activity-of-male-wistar-rats
#9
Omowumi Titilola Kayode, Musa Toyin Yakubu
OBJECTIVE: The leaves of Parquetina nigrescens have been claimed in folk medicine to be useful for managing sexual dysfunction, but there is inadequate scientific evidence for this claim. This investigation was conducted to assess the effects of aqueous leaf extract of Parquetina nigrescens (AEPN) in rats induced with sexual dysfunction. METHODS: Male rats were allocated into various groups after being induced into sexual dysfunction with paroxetine hydrochloride...
January 2017: Journal of Integrative Medicine
https://www.readbyqxmd.com/read/28087819/electrophysiologic-effects-of-the-ik1-inhibitor-pa-6-are-modulated-by-extracellular-potassium-in-isolated-guinea-pig-hearts
#10
Gregory S Hoeker, Mark A Skarsfeldt, Thomas Jespersen, Steven Poelzing
The pentamidine analog PA-6 was developed as a specific inward rectifier potassium current (IK1) antagonist, because established inhibitors either lack specificity or have side effects that prohibit their use in vivo. We previously demonstrated that BaCl2, an established IK1 inhibitor, could prolong action potential duration (APD) and increase cardiac conduction velocity (CV). However, few studies have addressed whether targeted IK1 inhibition similarly affects ventricular electrophysiology. The aim of this study was to determine the effects of PA-6 on cardiac repolarization and conduction in Langendorff-perfused guinea pig hearts...
January 2017: Physiological Reports
https://www.readbyqxmd.com/read/28087519/sympathetic-modulation-of-electrical-activation-in-normal-and-infarcted-myocardium-implications-for-arrhythmogenesis
#11
Olujimi A Ajijola, Robert L Lux, Anadjeet Khahera, OhJin Kwon, Eric Aliotta, Daniel Ennis, Michael C Fishbein, Jeffrey Laurence Ardell, Kalyanam Shivkumar
: Background The influence of cardiac sympathetic innervation on electrical activation in normal and chronically infarcted ventricular myocardium is not understood. Methods and Results Yorkshire pigs with normal hearts (NL, n=12) or anterior myocardial infarction (MI, n=9) underwent high-resolution mapping of the anteroapical left ventricle, at baseline, and during left and right stellate ganglion stimulation (LSGS & RSGS, respectively). Conduction velocity (CV), activation times (AT), & directionality of propagation were measured...
January 13, 2017: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/28087483/cell-number-per-spheroid-and-electrical-conductivity-of-nanowires-influence-the-function-of-silicon-nanowired-human-cardiac-spheroids
#12
Yu Tan, Dylan Richards, Robert C Coyle, Jenny Yao, Ruoyu Xu, Wenyu Gou, Hongjun Wang, Donald R Menick, Bozhi Tian, Ying Mei
: Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) provide an unlimited cell source to treat cardiovascular diseases, the leading cause of death worldwide. However, current hiPSC-CMs retain an immature phenotype that leads to difficulties for integration with adult myocardium after transplantation. To address this, we recently utilized electrically conductive silicon nanowires (e-SiNWs) to facilitate self-assembly of hiPSC-CMs to form nanowired hiPSC cardiac spheroids...
January 10, 2017: Acta Biomaterialia
https://www.readbyqxmd.com/read/28087409/thioredoxin-a-novel-biomarker-of-post-injury-sepsis
#13
Jesper Eriksson, Andreas Gidlöf, Mikael Eriksson, Emma Larsson, Olof Brattström, Anders Oldner
BACKGROUND: Thioredoxin (TRX), an endogenous anti-oxidant protein induced in inflammatory conditions, has been shown to increase in plasma and to be associated with outcome in septic patients. This biomarker has never been studied in a trauma setting. We hypothesized that TRX would be increased after trauma and associated with post-injury sepsis. METHODS: Single-centre prospective observational study conducted at the intensive care unit (ICU) at the Karolinska University Hospital, Stockholm, Sweden, a level-1 trauma centre...
January 10, 2017: Free Radical Biology & Medicine
https://www.readbyqxmd.com/read/28087371/use-of-the-heart-pathway-with-high-sensitivity-cardiac-troponins-a-secondary-analysis
#14
Simon A Mahler, Jason P Stopyra, Fred S Apple, Robert F Riley, Gregory B Russell, Brian C Hiestand, James W Hoekstra, Cedric W Lefebvre, Bret A Nicks, David M Cline, Kim L Askew, David M Herrington, Gregory L Burke, Chadwick D Miller
OBJECTIVES: The HEART Pathway combines a decision aid and serial contemporary cardiac troponin I (cTnI) measures to achieve >99% sensitivity for major adverse cardiac events (MACE) at 30days and early discharge rates >20%. However, the impact of integrating high-sensitivity troponin (hs-cTn) measures into the HEART Pathway has yet to be determined. In this analysis we compare test characteristics of the HEART Pathway using hs-cTnI, hs-cTnT, or cTnI. DESIGN &METHODS: A secondary analysis of participants enrolled in the HEART Pathway RCT was conducted...
January 10, 2017: Clinical Biochemistry
https://www.readbyqxmd.com/read/28086891/measurement-of-electrocardiograms-in-a-bath-through-tap-water-utilizing-capacitive-coupling-electrodes-placed-outside-the-bathtub-wall
#15
Kosuke Motoi, Yasuhiro Yamakoshi, Takehiro Yamakoshi, Hiroaki Sakai, Naoto Tanaka, Ken-Ichi Yamakoshi
BACKGROUND: Taking a bath sometimes poses a risk for subjects with chronic cardiopulmonary disorders, due to the thermal effect and water pressure on his/her body. The ECG measurement would be helpful for the early recognition of abnormal cardiac beats and respiratory conditions. This paper describes a new attempt to improve on previous bathtub ECG measurement techniques that had electrodes placed inside the bathtub that were intrusive to the subjects' bathing experience. This study is concerned with the initial development of a method to measure an electrocardiogram (ECG) through tap water without conscious awareness of the presence of electrodes that are placed outside the bathtub wall...
January 11, 2017: Biomedical Engineering Online
https://www.readbyqxmd.com/read/28086779/the-effect-of-electrical-conductivity-of-myocardium-on-cardiac-pumping-efficacy-a-computational-study
#16
Ana Rahma Yuniarti, Ki Moo Lim
BACKGROUND AND AIMS: The existence of non-excitable cells in the myocardium leads to the increasing conduction non-uniformity and decreasing myocardial electrical conductivity. Slowed myocardial conduction velocity (MCV) believed to enhance the probability of cardiac arryhthmia and alter the cardiac mechanical pumping efficacy, even in sinus rhythm. Though several studies on the correlation between MCV and cardiac electrical instabilities exist, there has been no study concerning correlation or causality between MCV and cardiac mechanical pumping efficacy, due to the limitation in clinical methods to document and evaluate cardiac mechanical responses directly...
January 10, 2017: Biomedical Engineering Online
https://www.readbyqxmd.com/read/28078997/lipoprotein-a-and-cardiovascular-risk-the-show-must-go-on
#17
Niki Katsiki, Khalid Al-Rasadi, Dimitri P Mikhailidis
Lipoprotein (a) [Lp(a)] is an independent but moderate, predictor for coronary heart disease (CHD) prevalence and severity. Several established and emerging cardiovascular (CV) risk factors including age, gender, ethnicity, smoking, dyslipidemia, hypertension, obesity, type 2 diabetes mellitus, alcohol consumption, arterial stiffness and hyperuricemia have been linked to Lp(a) metabolism. Apart from CHD, Lp(a) has been also associated with non-cardiac vascular diseases and diseases associated with increased CV risk such as chronic kidney disease, metabolic syndrome, non-alcoholic fatty liver disease, erectile dysfunction, obstructive sleep apnea syndrome, inflammatory bowel diseases and human immunodeficiency virus infection...
January 12, 2017: Current Medicinal Chemistry
https://www.readbyqxmd.com/read/28078759/bufalin-a-bufanolide-steroid-from-the-parotoid-glands-of-the-chinese-toad-inhibits-l-type-ca-2-channels-and-contractility-in-rat-ventricular-myocytes
#18
Tao Song, Xi Chu, Xuan Zhang, Qiong Tao Song, Ying Zhang, Yuanyuan Zhang, Xue Han, Jianping Zhang, Li Chu
Bufalin is a bufanolide steroid compound in Chan Su. Chan Su is a traditional Chinese medicine prepared from the dried white secretion of the auricular and skin glands of toads, and has been used as an Oriental drug. However, the effect of bufalin on cardiac function and its underlying cellular mechanisms remain unclear. Here, we explore the cellular mechanisms of bufalin on myocardial protection via the whole-cell patch-clamp recording and video-based edge detection system. Exposure to bufalin resulted in a concentrated-dependent blockade of ICa-L , with the half-maximal inhibitory concentration (IC50 ) of 60 μM and the maximal inhibitory effect of 71...
January 11, 2017: Fundamental & Clinical Pharmacology
https://www.readbyqxmd.com/read/28078682/population-pharmacokinetics-of-intravenous-clonidine-for-sedation-during-pediatric-extracorporeal-membrane-oxygenation-ecmo-and-continuous-veno-venous-hemofiltration-cvvh
#19
Niina Kleiber, Ron A A Mathôt, Maurice J Ahsman, Enno D Wildschut, Dick Tibboel, Saskia N de Wildt
AIMS: Clonidine is used for sedation in the pediatric intensive care unit. Extracorporeal membrane oxygenation (ECMO) provides temporary support if respiratory and cardiac function is threatened. ECMO influences the pharmacokinetics of drugs. Clonidine during pediatric ECMO cannot be effectively titrated as PK data are lacking. The aim of this study is to describe clonidine PK in a particular ECMO system and propose dosing guidelines for children on this particular ECMO circuit. METHODS: All children below the age of 18 who received clonidine during ECMO were eligible...
January 12, 2017: British Journal of Clinical Pharmacology
https://www.readbyqxmd.com/read/28077904/regadenoson-in-myocardial-perfusion-study-first-institutional-experiences-in-bosnia-and-herzegovina
#20
Nermina Beslic, Renata Milardovic, Amera Sadija, Sejla Ceric, Zeljka Raic
INTRODUCTION: Myocardial perfusion imaging (MPI) is widely used in the evaluation of known and suspected coronary artery disease (CAD). Imaging of heart in stress and rest enables the comparison of myocardial uptake of radiotracer in proportion to the needs and coronary flow, which is used for detection of perfusion defects. Exercise stress and pharmacologic agents are used for the stressing purpose. Novel pharmacologic stressor regadenoson is A2A selective adenosine agonist, which selectively binds to the adenosine receptors in coronary arteries causing coronary dilatation...
December 2016: Acta Informatica Medica: AIM
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