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https://www.readbyqxmd.com/read/29330651/3d-computed-tomography-to-compare-the-dimensions-of-the-left-atrial-appendage-in-patients-with-normal-sinus-rhythm-and-those-with-paroxysmal-atrial-fibrillation
#1
Maiko Hozawa, Yoshihiro Morino, Yuki Matsumoto, Ryoichi Tanaka, Kyohei Nagata, Akiko Kumagai, Atsushi Tashiro, Akio Doi, Kunihiro Yoshioka
Although paroxysmal atrial fibrillation (PAF) is an important cause of cardioembolic stroke, in contrast to chronic AF patients, the anatomical features of the left atrial appendage (LAA) in PAF patients remain unknown. Here, we investigated differences in LAA structures in patients with PAF and those with normal sinus rhythms (NSR) using 3D-computed tomography (3D-CT), which allows us to visualize complicated LAA structures at high spatial resolution. Study subjects were 30 consecutive PAF and 30 NSR patients with complete enhanced cardiac 3D-CT images available...
January 12, 2018: Heart and Vessels
https://www.readbyqxmd.com/read/29329947/-pseudoexfoliation-syndrome-and-pseudoexfoliation-glaucoma
#2
REVIEW
C Schweitzer
Pseudoexfoliation syndrome is an age-related systemic disease that mainly affects the anterior structures of the eye. Despite a worldwide distribution, reported incidence and prevalence of this syndrome vary widely between ethnicities and geographical areas. The exfoliative material is composed mainly of abnormal cross-linked fibrils that accumulate progressively in some organs such as the heart, blood vessels, lungs or meninges, and particularly in the anterior structures of the eye. The exact pathophysiological process still remains unclear but the association of genetic and environmental factors are thought to play a role in the development and progressive extracellular accumulation of exfoliative material...
January 9, 2018: Journal Français D'ophtalmologie
https://www.readbyqxmd.com/read/29327362/p-wave-and-interatrial-block-new-predictor-for-atrial-high-rate-episodes-in-patients-with-cardiac-implantable-electronic-devices
#3
José M Rubio Campal, Juan Benezet-Mazuecos, José Antonio Iglesias Bravo, Pepa Sánchez Borque, Ángel Miracle Blanco, Juan José de la Vieja Alarcón, Jaime Martínez Mariscal, Adrian M Baranchuk, Jerónimo Farré Muncharaz
BACKGROUND: The presence of interatrial block (IAB) is associated with the development of atrial fibrillation (AF). The aim of this study was to determine whether P-wave duration and presence of IAB before the implantation of a cardiac implantable electronic device (CIED) are associated with the presence of atrial high rate episodes (AHRE), during long-term follow-up. METHODS: 380 patients (57% men; 75±10 years) were included. IAB was defined according to the International Consensus Criteria...
January 12, 2018: Pacing and Clinical Electrophysiology: PACE
https://www.readbyqxmd.com/read/29327256/targeting-atrial-fibrillation-promoting-atrial-structural-remodeling-is-this-a-viable-strategy-in-patients-with-heart-failure
#4
EDITORIAL
Na Li, Dobromir Dobrev
No abstract text is available yet for this article.
January 11, 2018: Naunyn-Schmiedeberg's Archives of Pharmacology
https://www.readbyqxmd.com/read/29324263/the-role-of-pro-fibrotic-biomarkers-in-paroxysmal-and-persistent-atrial-fibrillation
#5
Adina Elena Stanciu, Radu Gabriel Vatasescu, Marcel Marian Stanciu, Nafija Serdarevic, Maria Dorobantu
PURPOSE: Signaling pathways involved in electrical, structural and contractile remodeling processes behind development and progression of atrial fibrillation (AF) have not been completely elucidated, but it seems to be related to complex interactions among neurohormonal and cellular mediators. We aimed to investigate interleukin-6 (IL-6), transforming growth factor-beta1 (TGF-β1), matrix metalloproteinase-9 (MMP-9), tissue inhibitor of metalloproteinase-1 (TIMP-1), as biomarkers of atrial remodeling, in patients with paroxysmal and persistent AF, and their correlation with N-terminal prohormone of brain natriuretic peptide (NT-proBNP) and left atrial (LA) diameter...
January 8, 2018: Cytokine
https://www.readbyqxmd.com/read/29323823/atrioesophageal-fistula-a-rare-complication-of-radiofrequency-ablation
#6
Inbar Saporta, Adithya Chennamadhavuni, Michael J Dolan
75-year-old woman was admitted with fever, chills, altered mentation, and right-sided weakness. A month earlier, she had undergone catheter radiofrequency ablation for treatment of chronic atrial fibrillation. A magnetic resonance imaging scan of her brain revealed septic emboli with multiple bilateral cerebral and cerebellar infarcts, as well as extensive bilateral leptomeningeal enhancement. Blood cultures were positive for Streptococcus mitis, Rothia mucilaginosa, Streptococcus pneumonia, and Candida albicans, which suggested a connection between gastrointestinal and cardiovascular systems...
June 2017: WMJ: Official Publication of the State Medical Society of Wisconsin
https://www.readbyqxmd.com/read/29322650/molecular-characterization-of-the-%C3%AE-amyloid-4-10-epitope-of-plaque-specific-a%C3%AE-antibodies-by-affinity-mass-spectrometry-using-alanine-site-mutation
#7
Raluca Ștefănescu, Loredana Lupu, Marilena Manea, Roxana E Iacob, Michael Przybylski
Alzheimer disease is a neurodegenerative disease affecting an increasing number of patients worldwide. Current therapeutic strategies are directed to molecules capable to block the aggregation of the β-amyloid(1-42) (Aβ) peptide and its shorter naturally occurring peptide fragments into toxic oligomers and amyloid fibrils. Aβ-specific antibodies have been recently developed as powerful antiaggregation tools. The identification and functional characterization of the epitope structures of Aβ antibodies contributes to the elucidation of their mechanism of action in the human organism...
January 2018: Journal of Peptide Science: An Official Publication of the European Peptide Society
https://www.readbyqxmd.com/read/29321418/optimal-medications-and-appropriate-implantable-cardioverter-defibrillator-shocks-in-aborted-sudden-cardiac-death-due-to-coronary-spasm
#8
Shozo Sueda, Hiroaki Kohno
Background Life-threatening ventricular arrhythmias are recognized in patients with coronary spastic angina. Implantable cardioverter-defibrillators (ICDs) are effective in patients with structural heart disease and ventricular fibrillation. However, the optimal medication for patients with aborted sudden cardiac death (SCD) due to coronary artery spasm after the implantation of ICD remains controversial. Methods We investigated the medications and the numbers of appropriate ICD shocks in 137 patients with a history of aborted SCD due to coronary spasm...
January 11, 2018: Internal Medicine
https://www.readbyqxmd.com/read/29319162/a-long-lived-a%C3%AE-oligomer-resistant-to-fibrillization
#9
Mimi Nick, Yibing Wu, Nathan W Schmidt, Stanley B Prusiner, Jan Stöhr, William F DeGrado
The hydrophobic Aβ peptide is highly aggregation prone; it first forms soluble oligomers, which then convert into the amyloid fibrils found in the cerebral plaques of Alzheimer's disease. It is generally understood that as the peptide concentration of Aβ increases, the fibrillization process is accelerated, but we examine the limits on this phenomenon. We found that once a threshold concentration of Aβ is exceeded, a stable oligomer is formed at the expense of fibril formation. The suppression of fibril formation was observed by amyloid-binding dye Thioflavin T and solution nuclear magnetic resonance (NMR)...
January 10, 2018: Biopolymers
https://www.readbyqxmd.com/read/29314823/amyloid-beta-peptide-vhhq-klvff-and-iiglmvggvv-domains-involved-in-fibrilization-afm-and-electrochemical-characterization
#10
Teodor Adrian Enache, Ana-Maria Chiorcea-Paquim, Ana Maria Oliveira-Brett
The time-dependent structural modifications and oxidation behavior of specifically chosen five short amyloid beta (Aβ) peptides, Aβ1-16, Aβ1-28, Aβ10-20, Aβ12-28, and Aβ17-42, fragments of the complete human Aβ1-40 peptide, were investigated by atomic force microscopy (AFM) and voltammetry. The objective was to determine the influence of different Aβ domains (VHHQ that contains electroactive histidine H residues, KLVFF that is the peptide hydrophobic aggregation core, and IIGLMVGGVV that is the C-terminus hydrophobic region), and of Aβ peptide hydrophobicity, in the fibrilization mechanism...
January 9, 2018: Analytical Chemistry
https://www.readbyqxmd.com/read/29314148/3d-reconstruction-of-the-porcine-and-equine-pulmonary-veins-supplemented-with-the-identification-of-telocytes-in-the-horse
#11
T Vandecasteele, W Van Den Broeck, H Tay, L Couck, G van Loon, P Cornillie
The myocardial sleeve of the porcine and equine pulmonary veins were histologically investigated and reconstructed three dimensionally. Moreover, the localization of neuron cell bodies at the veno-atrial junction and alongside the myocardial sleeve was light microscopically visualized to depict the organization of nerve, myocardial and fat tissue. Finally, the presence of telocytes inside the equine pulmonary veins was demonstrated by use of transmission electron microscopy. These structures are thought to play a role in the induction of atrial fibrillation, which is frequently seen in horses, while pigs are often used as a cardiovascular model in this context...
January 3, 2018: Anatomia, Histologia, Embryologia
https://www.readbyqxmd.com/read/29313531/fluorescence-spectroscopy-reveals-n-terminal-order-in-fibrillar-forms-of-%C3%AE-synuclein
#12
Conor M Haney, E James Petersson
The neuronal protein α-synuclein (αS) plays a key role in Parkinson's disease, forming inclusions termed Lewy bodies and Lewy neurites. Recent improvements in cryo-electron diffraction and solid state NMR (ssNMR) have led to the elucidation of the structures of peptides derived from the αS fibril core and full-length human αS in fibrils. Despite the valuable insight offered by these methods, there are still several questions about the structures' relevance to pathological aggregates. Herein, we present fluorescence data collected in vitro under the conditions which fibrils are typically assembled...
January 9, 2018: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/29311706/mechanistic-insights-into-remodeled-tau-derived-phf6-peptide-fibrils-by-naphthoquinone-tryptophan-hybrids
#13
V Guru KrishnaKumar, Ashim Paul, Ehud Gazit, Daniel Segal
Intra-cellular tau protein tangles and extra-cellular β-amyloid plaques are hallmarks of Alzheimer's disease (AD), characterized by the conversion of natively unfolded monomeric protein/peptide into misfolded β-sheet rich aggregates. Therefore, inhibiting the aggregation cascade or disassembling the pre-formed aggregates becomes a pivotal event in disease treatment. In the present study, we show that Naphthoquinone-Tryptophan hybrids, i.e., NQTrp and Cl-NQTrp significantly disrupted the pre-formed fibrillar aggregates of Tau-derived PHF6 (VQIVYK) peptide and full-length tau protein in vitro, in a dose-dependent manner as evident from ThS assay, CD spectroscopy, and TEM...
January 8, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29311640/a-specific-form-of-prefibrillar-aggregates-that-functions-as-a-precursor-of-amyloid-nucleation
#14
Naoki Yamamoto, Shoko Tsuhara, Atsuo Tamura, Eri Chatani
Non-fibrillar protein aggregates that appear in the earlier stages of amyloid fibril formation are sometimes considered to play a key role in amyloid nucleation; however, the structural features of these aggregates currently remain unclear. We herein identified a characteristic pathway of fibril formation by human insulin B chain, in which two major species of prefibrillar aggregates were identified. Based on the time-resolved tracking of this pathway with far-UV circular dichroism (CD) spectroscopy, dynamic light scattering (DLS), and 1H-NMR spectroscopy, the first prefibrillar aggregate with a hydrodynamic diameter of approximately 70 nm accumulated concomitantly with the formation of a β-sheet structure, and the size further evolved to 130 nm with an additional structural development...
January 8, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29311465/-amyloid-selective-photooxygenation-toward-treatment-for-amyloid-diseases
#15
Atsuhiko Taniguchi
 Amyloid proteins and peptides form aggregates which lead to amyloid diseases. For example, Alzheimer's disease-related amyloid β (Aβ) forms oligomers, protofibrils, and amyloid fibrils, which exhibit neurotoxicity. Controlling the aggregation and toxicity of Aβ would be a therapeutic strategy for the treatment of Alzheimer's disease. Recently, we have investigated an artificial oxygenative modification (chemical introduction of oxygen atoms) of amyloid proteins using a photocatalyst, which attenuated the aggregation potency and toxicity of these proteins...
2018: Yakugaku Zasshi: Journal of the Pharmaceutical Society of Japan
https://www.readbyqxmd.com/read/29311311/structural-heterogeneity-and-intersubject-variability-of-a%C3%AE-in-familial-and-sporadic-alzheimer-s-disease
#16
Carlo Condello, Thomas Lemmin, Jan Stöhr, Mimi Nick, Yibing Wu, Alison M Maxwell, Joel C Watts, Christoffer D Caro, Abby Oehler, C Dirk Keene, Thomas D Bird, Sjoerd G van Duinen, Lars Lannfelt, Martin Ingelsson, Caroline Graff, Kurt Giles, William F DeGrado, Stanley B Prusiner
Point mutations in the amyloid-β (Aβ) coding region produce a combination of mutant and WT Aβ isoforms that yield unique clinicopathologies in familial Alzheimer's disease (fAD) and cerebral amyloid angiopathy (fCAA) patients. Here, we report a method to investigate the structural variability of amyloid deposits found in fAD, fCAA, and sporadic AD (sAD). Using this approach, we demonstrate that mutant Aβ determines WT Aβ conformation through prion template-directed misfolding. Using principal component analysis of multiple structure-sensitive fluorescent amyloid-binding dyes, we assessed the conformational variability of Aβ deposits in fAD, fCAA, and sAD patients...
January 8, 2018: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/29310792/nonlinear-optical-imaging-of-extracellular-matrix-proteins
#17
Chien-Cheng Shih, Dennis M Oakley, Matthew S Joens, Robyn A Roth, James A J Fitzpatrick
Over the last 2 decades, nonlinear imaging methods such as multiharmonic imaging microscopy (MHIM) have become powerful approaches for the label-free visualization of biological structures. Multiharmonic signals are generated when an intense electromagnetic field propagates through a sample that either has a specific molecular orientation or exhibits certain physical properties. It can provide complementary morphological information when integrated with other nonlinear optical imaging techniques such as two-photon excitation (TPE)...
2018: Methods in Cell Biology
https://www.readbyqxmd.com/read/29303519/teaching-an-old-scaffold-new-recognition-tricks-oligopyrrolamide-antagonists-of-iapp-aggregation
#18
Sunil Kumar, Maria C Vogel, Andrew D Hamilton
A library of N-substituted oligopyrrolamides was designed to modulate the aggregation kinetics of islet amyloid polypeptide (IAPP). IAPP is a hormonal peptide, co-secreted with insulin in the pancreatic β-cells. IAPP samples a variety of conformations, starting from a native random coil to membrane-associated α-helical intermediates and eventually terminates in the amyloid plaques rich in β-sheet structures. A growing body of evidence suggests that membrane bound α-helical intermediates are the key cytotoxic species that impair the functionality and viability of β-cells and contribute to the onset of type 2 diabetes mellitus (DM2)...
January 5, 2018: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/29300976/integrating-new-approaches-to-atrial-fibrillation-management-the-6th-afnet-ehra-consensus-conference
#19
Dipak Kotecha, Günter Breithardt, A John Camm, Gregory Y H Lip, Ulrich Schotten, Anders Ahlsson, David Arnar, Dan Atar, Angelo Auricchio, Jeroen Bax, Stefano Benussi, Carina Blomstrom-Lundqvist, Martin Borggrefe, Giuseppe Boriani, Axel Brandes, Hugh Calkins, Barbara Casadei, Manuel Castellá, Winnie Chua, Harry Crijns, Dobromir Dobrev, Larissa Fabritz, Martin Feuring, Ben Freedman, Andrea Gerth, Andreas Goette, Eduard Guasch, Doreen Haase, Stephane Hatem, Karl Georg Haeusler, Hein Heidbuchel, Jeroen Hendriks, Craig Hunter, Stefan Kääb, Stefanie Kespohl, Ulf Landmesser, Deirdre A Lane, Thorsten Lewalter, Lluís Mont, Michael Nabauer, Jens C Nielsen, Michael Oeff, Jonas Oldgren, Ali Oto, Laurent Pison, Tatjana Potpara, Ursula Ravens, Isabelle Richard-Lordereau, Michiel Rienstra, Irina Savelieva, Renate Schnabel, Moritz F Sinner, Philipp Sommer, Sakis Themistoclakis, Isabelle C Van Gelder, Panagiotis E Vardas, Atul Verma, Reza Wakili, Evelyn Weber, David Werring, Stephan Willems, André Ziegler, Gerhard Hindricks, Paulus Kirchhof
There are major challenges ahead for clinicians treating patients with atrial fibrillation (AF). The population with AF is expected to expand considerably and yet, apart from anticoagulation, therapies used in AF have not been shown to consistently impact on mortality or reduce adverse cardiovascular events. New approaches to AF management, including the use of novel technologies and structured, integrated care, have the potential to enhance clinical phenotyping or result in better treatment selection and stratified therapy...
January 2, 2018: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/29298645/the-inhibitory-effect-of-panax-ginseng-extract-on-amyloid-like-fibril-formation-of-trypsin-in-aqueous-ethanol
#20
Phanindra Babu Kasi, Marta Kotorman, Attila Borics, Beata Gabriella Hervay, Kinga Molnar, Lajos Laszlo
People have used ginseng as a traditional herbal medicine for over 2000 years, mainly for its protective effect against neurological disorders. In vitro studies were performed to study the formation of amyloid-like fibrils by the well-known protease trypsin as a model protein in 60% ethanol at pH 7.0. Possible inhibitory effects of ginseng extracts on the formation of amyloid-like fibrils was examined. The aggregation of trypsin was followed via turbidity measurements, aggregation kinetics, the Congo red (CR) binding assay, electronic circular dichroism (ECD) spectroscopy, size exclusion chromatography, and transmission electron microscopy (TEM) in the presence or absence of Panax ginseng extracts, as well as other, previously studied inhibitors of natural origin...
December 29, 2017: Protein and Peptide Letters
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