Read by QxMD icon Read

Junctional Rhythm

Jihwan Myung, Christoph Schmal, Sungho Hong, Yoshiaki Tsukizawa, Pia Rose, Yong Zhang, Michael J Holtzman, Erik De Schutter, Hanspeter Herzel, Grigory Bordyugov, Toru Takumi
Mammalian circadian clocks have a hierarchical organization, governed by the suprachiasmatic nucleus (SCN) in the hypothalamus. The brain itself contains multiple loci that maintain autonomous circadian rhythmicity, but the contribution of the non-SCN clocks to this hierarchy remains unclear. We examine circadian oscillations of clock gene expression in various brain loci and discovered that in mouse, robust, higher amplitude, relatively faster oscillations occur in the choroid plexus (CP) compared to the SCN...
March 14, 2018: Nature Communications
Shirley L Zhang, Zhifeng Yue, Denice M Arnold, Gregory Artiushin, Amita Sehgal
Endogenous circadian rhythms are thought to modulate responses to external factors, but mechanisms that confer time-of-day differences in organismal responses to environmental insults/therapeutic treatments are poorly understood. Using a xenobiotic, we find that permeability of the Drosophila "blood"-brain barrier (BBB) is higher at night. The permeability rhythm is driven by circadian regulation of efflux and depends on a molecular clock in the perineurial glia of the BBB, although efflux transporters are restricted to subperineurial glia (SPG)...
February 27, 2018: Cell
Yang Hongliang, Yu Ming, Zhao Qini, Si Daoyuan, Tong Yaliang, Wang Ying, He Yuquan
INTRODUCTION: Atrial premature contractions (APCs) are commonly encountered in clinical practice. The APCs may influence heart conduction system and induce other arrhythmia. The disorder of atrioventricular conduction is related to electrophysiological phenomena, difficult to understand and diagnose. CASE REPORT: We presented a 15-year-old male patient whose baseline electrocardiogram (ECG) was confused with multiple rhythms. Electrophysiological study results showed sinus rhythm with nonconducted APCs in bigeminal rhythm...
December 2017: Medicine (Baltimore)
Atsushi Sengiku, Masakatsu Ueda, Jin Kono, Takeshi Sano, Nobuyuki Nishikawa, Sumihiro Kunisue, Kojiro Tsujihana, Louis S Liou, Akihiro Kanematsu, Shigeki Shimba, Masao Doi, Hitoshi Okamura, Osamu Ogawa, Hiromitsu Negoro
Day-night changes in the storage capacity of the urinary bladder are indispensable for sound sleep. Connexin 43 (Cx43), a major gap junction protein, forms hemichannels as a pathway of ATP in other cell types, and the urinary bladder utilizes ATP as a mechanotransduction signals to modulate its capacity. Here, we demonstrate that the circadian clock of the urothelium regulates diurnal ATP release through Cx43 hemichannels. Cx43 was expressed in human and mouse urothelium, and clock genes oscillated in the mouse urothelium accompanied by daily cycles in the expression of Cx43 and extracellular ATP release into the bladder lumen...
January 31, 2018: Scientific Reports
Narges-Sadat Zahed, Hossein Hassanian-Moghaddam, Nasim Zamani
Using calcium salts in management of amlodipine overdose is challenging. A 25-year-old male with known history of adult polycystic kidney disease presented with hypotension, tachycardia, and intact neurological status after ingestion of 450 mg of amlodipine. Immediately, normal saline infusion and norepinephrine were initiated. Two grams of calcium gluconate was injected, followed by intravenous infusion of 1.16 mg/kg/h. The patient was put on insulin-glucose protocol to maintain euglycemia and hyperinsulinemia...
January 30, 2018: Cardiovascular Toxicology
Michael P Notter, Michael Hanke, Micah M Murray, Eveline Geiser
The perception of an acoustic rhythm is invariant to the absolute temporal intervals constituting a sound sequence. It is unknown where in the brain temporal Gestalt, the percept emerging from the relative temporal proximity between acoustic events, is encoded. Two different relative temporal patterns, each induced by three experimental conditions with different absolute temporal patterns as sensory basis, were presented to participants. A linear support vector machine classifier was trained to differentiate activation patterns in functional magnetic resonance imaging data to the 2 different percepts...
January 20, 2018: Cerebral Cortex
Shangbang Gao, Sihui Asuka Guan, Anthony D Fouad, Jun Meng, Taizo Kawano, Yung-Chi Huang, Yi Li, Salvador Alcaire, Wesley Hung, Yangning Lu, Yingchuan Billy Qi, Yishi Jin, Mark Alkema, Christopher Fang-Yen, Mei Zhen
Cell- or network-driven oscillators underlie motor rhythmicity. The identity of C. elegans oscillators remains unknown. Through cell ablation, electrophysiology, and calcium imaging, we show: (1) forward and backward locomotion is driven by different oscillators; (2) the cholinergic and excitatory A-class motor neurons exhibit intrinsic and oscillatory activity that is sufficient to drive backward locomotion in the absence of premotor interneurons; (3) the UNC-2 P/Q/N high-voltage-activated calcium current underlies A motor neuron's oscillation; (4) descending premotor interneurons AVA, via an evolutionarily conserved, mixed gap junction and chemical synapse configuration, exert state-dependent inhibition and potentiation of A motor neuron's intrinsic activity to regulate backward locomotion...
January 23, 2018: ELife
Stephen A Busch, Hannah E Davies, Sean Van Diepen, Lydia L Simpson, Frances Sobierajski, Laurel Riske, Mike Stembridge, Philip N Ainslie, Christopher K Willie, Ryan L Hoiland, Jonathan P Moore, Craig D Steinback
Peripheral chemoreflex mediated increases in both parasympathetic and sympathetic drive under chronic hypoxia may evoke brady-arrhythmias during apneic periods. We determined if: a) voluntary apnea unmasks arrhythmia at sea level and altitude (5050m), b) if high altitude natives (Nepalese Sherpa) exhibit similar cardiovagal responses at altitude; and c) if brady-arrhythmias at altitude are partially chemoreflex mediated. Participants were grouped as Lowlanders (n=14; age=27{plus minus}6yrs) and Nepalese Sherpa (n=8; age=32{plus minus}11yrs)...
December 21, 2017: Journal of Applied Physiology
Alhafidz Hamdan, A Saxena, G Rao, M Ivanov
Transient anoxic seizure upon application of pressure on a giant pseudomeningocele has never been reported in the literature; such abrupt changes in intracranial pressure due to large volume of cerebrospinal fluid (CSF) translocation, if left untreated may lead to permanent cerebral hypoxic injury and death. Here we describe a case of a 26-year-old woman who had undergone lumbar disc surgery in another unit few months ago and developed a large lump around her back. Any pressure on the lump resulted in headaches and at times episodes of seizures...
January 3, 2018: Acta Neurochirurgica
Maurizio Gasparini, Axel Kloppe, Maurizio Lunati, Frédéric Anselme, Maurizio Landolina, Jose Bautista Martinez-Ferrer, Alessandro Proclemer, Giovanni Morani, Mauro Biffi, Renato Ricci, Roberto Rordorf, Lorenza Mangoni, Laura Manotta, Andrea Grammatico, Francisco Leyva, Giuseppe Boriani
AIMS: We sought to determine whether atrioventricular junction ablation (AVJA) in patients with cardiac resynchronization therapy (CRT) implantable cardioverter-defibrillator (ICD) and with permanent atrial fibrillation (AF) has a positive impact on ICD shocks and hospitalizations compared with rate-slowing drugs. METHODS AND RESULTS: This is a pooled analysis of data from 179 international centres participating in two randomized trials and one prospective observational research...
December 18, 2017: European Journal of Heart Failure
Ji-Eun Ban
Arrhythmias in the neonatal period are not uncommon, and may occur in neonates with a normal heart or in those with structural heart disease. Neonatal arrhythmias are classified as either benign or nonbenign. Benign arrhythmias include sinus arrhythmia, premature atrial contraction, premature ventricular contraction, and junctional rhythm; these arrhythmias have no clinical significance and do not need therapy. Supraventricular tachycardia, ventricular tachycardia, atrioventricular conduction abnormalities, and genetic arrhythmia such as congenital long-QT syndrome are classified as nonbenign arrhythmias...
November 2017: Korean Journal of Pediatrics
Shigeru Kitazawa
It has been proposed that a position in time can be discriminated in two ways. First, each position is either past, present, or future (A series). Second, each position is either before or after another (B series). In this review, we aim to infer how the two series are represented in the brain on the basis of findings from clinical, neurophysiological, and neuroimaging studies. We suggest that the precuneus and posterior cingulate cortex are critically involved in the A series. In the B series, we suggest that a group of events are represented in space around the intraparietal cortex and are combined with the temporal directional cue provided by the motion signals in the left temporo-parietal junction...
November 2017: Brain and Nerve, Shinkei Kenkyū No Shinpo
Tylor R Lewis, Mariusz Zareba, Brian A Link, Joseph C Besharse
Teleosts and amphibians exhibit retinomotor movements, morphological changes in photoreceptors regulated by light and circadian rhythms. Cone myoid elongation occurs during dark adaptation leading to the positioning of the cone outer segment closer to the retinal pigment epithelium. While it has been shown that microtubules are essential for cone myoid elongation, the underlying mechanism has not been established. In this work, we generated a transgenic line of zebrafish expressing a photoconvertible form of α-tubulin (tdEOS-tubulin) specifically in cone photoreceptors...
November 15, 2017: Molecular Biology of the Cell
Hui-Ting Wang, Wen-Hao Liu, Yung-Lung Chen
RATIONALE: More mature or older women are more likely to undergo in vitro fertilization and embryo implant. These women have a greater chance of receiving ergonovine therapy because of a suspected abortion. We present this case report to call attention to a latent lethal adverse effect in everyday obstetric practice using ergonovine. It requires more attention and close monitoring PATIENT CONCERNS:: We presented the case of a 38-year-old female patient with general weakness and mild chest tightness after ergonovine use...
November 2017: Medicine (Baltimore)
Debbie Guatelli-Steinberg, James D Pampush, Mackie C O'Hara, Song Xing, W Scott McGraw, Rebecca J Ferrell
Enamel formation front (EFF) angles represent the leading edge of enamel matrix secretion at particular points in time. These angles are influenced by rates of enamel extension (the rates at which tooth crowns grow in height), rates of enamel matrix secretion and the angles that prisms make with the enamel-dentine junction. Previous research suggests, but has not yet established, that these angles reflect aspects of primate biology related to their pace of growth and development, most notably brain and body size...
January 2018: Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology
Ana Abreu, Mário Oliveira, Pedro Silva Cunha, Helena Santa Clara, Guilherme Portugal, Inês Gonçalves Rodrigues, Vanessa Santos, Luís Morais, Mafalda Selas, Rui Soares, Luísa Branco, Rui Ferreira, Miguel Mota Carmo
INTRODUCTION: The benefits of cardiac resynchronization therapy (CRT) documented in heart failure (HF) may be influenced by atrial fibrillation (AF). We aimed to compare CRT response in patients in AF and in sinus rhythm (SR). METHODS: We prospectively studied 101 HF patients treated by CRT. Rates of clinical, echocardiographic and functional response, baseline NYHA class and variation, left ventricular ejection fraction, volumes and mass, atrial volumes, cardiopulmonary exercise test (CPET) duration (CPET dur), peak oxygen consumption (VO2max) and ventilatory efficiency (VE/VCO2 slope) were compared between AF and SR patients, before and at three and six months after implantation of a CRT device...
October 2017: Portuguese Journal of Cardiology: An Official Journal of the Portuguese Society of Cardiology
Syeda Atiqa Batul, Rakesh Gopinathannair
Atrial fibrillation (AF) and heart failure (HF) are growing cardiovascular disease epidemics worldwide. There has been an exponential increase in the prevalence of AF and HF correlating with an increased burden of cardiac risk factors and improved survival rates in patients with structural heart disease. AF is associated with adverse prognostic outcomes in HF and is most evident in mild-to-moderate left ventricular (LV) dysfunction where the loss of "atrial kick" translates into poorer quality of life and increased mortality...
September 2017: Korean Circulation Journal
Juan Ruiz-García, Luis Borrego-Bernabé, Irene Canal-Fontcuberta, Eduardo Alegría-Barrero
No abstract text is available yet for this article.
October 2017: Archivos de Cardiología de México
Nicole Durfey, Brian Lehnhof, Andrew Bergeson, Shayla N M Durfey, Victoria Leytin, Kristina McAteer, Eric Schwam, Justin Valiquet
INTRODUCTION: The electrocardiogram (ECG) is often used to identify which hyperkalemic patients are at risk for adverse events. However, there is a paucity of evidence to support this practice. This study analyzes the association between specific hyperkalemic ECG abnormalities and the development of short-term adverse events in patients with severe hyperkalemia. METHODS: We collected records of all adult patients with potassium (K+) ≥6.5 mEq/L in the hospital laboratory database from August 15, 2010, through January 30, 2015...
August 2017: Western Journal of Emergency Medicine
Naotaka Kishimoto, Ikue Kinoshita, Yoshihiro Momota
We report a case of junctional rhythm that occurred both preoperatively and later during a portion of general anesthesia. A 19-year-old woman was scheduled to undergo bilateral sagittal split ramus osteotomy after being diagnosed with a jaw deformity. Preoperative electrocardiography (ECG) revealed a junctional rhythm with a slow heart rate (HR). At 90 minutes after anesthesia induction, local anesthesia with 10 mL of 1% lidocaine and 1:100,000 adrenaline was administered. A junctional rhythm appeared 15 minutes after the local anesthesia...
2017: Anesthesia Progress
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"