The purpose of this study is to elucidate electrophysiological determinants of double ventricular response (DVR) to a single atrial extrastimulus in Wolff-Parkinson-White (WPW) syndrome. DVR was observed in 5 (3.4%) out of 146 consecutive patients with WPW syndrome. The site of accessory pathway was located in left lateral free wall in four patients and posterior septum in one. DVR was induced by extrastimulus from coronary sinus in four patients with left-sided accessory pathway, and from both coronary sinus and high right atrium in a patient with septal accessory pathway. However, it was not possible to induce DVR from high right atrium in patients with left-sided accessory pathway, because 50 to 80 ms are needed for intra-atrial conduction from high right atrium to coronary sinus. Critical prolongation of normal AV conduction allowing DVR was seen in the slow pathway of AV node in four patients. In the remaining patients requisite conduction delay occurred in both AV node and His-Purkinje system. Single right ventricular extrastimulus could easily elicit orthodromic AV reciprocating tachycardia or echo beat in four out of five patients and incremental ventricular stimulation induced it in the remaining patient, indicating the presence of retrograde block in the normal AV pathway. As requisites of DVR to a single atrial extrastimulus in WPW syndrome: (1) slow antegrade conduction and retrograde block in the normal AV pathway; and (2) stimulation site in the vicinity of accessory pathway, are needed.
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Front Immunol
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Department of Hepatology, Center for Pathogen Biology and Infectious Diseases, Institute of Translational Medicine, The First Hospital of Jilin University, Changchun, Jilin, China.
The intricate link between cholesterol metabolism and host immune responses is well recognized, but the specific mechanisms by which cholesterol biosynthesis influences hepatitis B virus (HBV) replication remain unclear. In this study, we show that SREBP2, a key regulator of cholesterol metabolism, inhibits HBV replication by interacting directly with the HBx protein, thereby preventing its nuclear translocation. We also found that inhibiting the ER-to-Golgi transport of the SCAP-SREBP2 complex or blocking SREBP2 maturation significantly enhances HBV suppression.
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Departamento de Agronomía, Universidad Nacional José Faustino Sánchez Carrión (UNJFSC), Lima 15136, Peru.
Bioremediation induced by bacteria offers a promising alternative for the contamination of aromatic hydrocarbons due to their metabolic processes suitable for the removal of these pollutants, as many of them are carcinogenic molecules and dangerous to human health. Our research focused on isolating a bacterium from the rhizosphere of the tara tree with the ability to degrade polycyclic aromatic hydrocarbons, using draft genomic sequencing and computational analysis. sp.
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Department of Cardiovascular Medicine, Dokkyo Medical University, 880 Kitakobayashi, Mibu, Shimotsugagun, Tochigi, 321-0293, Japan.
Background: The conventional mapping approach for the atrioventricular accessory pathway (AP) involves point-by-point mapping to identify the connection sites of the AP to the atria or ventricle and accurate interpretation of local electrograms. Omnipolar mapping technology (OMT) explains how vector and wave speed are produced by using both unipolar and bipolar signals to obtain omnipolar signals, directions, and conduction velocity. The aim of this study is to verify the effectiveness of OMT for catheter ablation of AP.
View Article and Find Full Text PDFSci Rep
January 2025
College of Life and Environmental Sciences, University of Exeter, Biosciences, Exeter, EX4 4QD, UK.
The mangrove killifish, Kryptolebias marmoratus, can reproduce with self-fertilisation, offering a unique and useful genetic tool for generation of genetic mutants and quick identification of mutated genes. From an ENU-mutated mangrove killifish line R228, we have isolated a novel mutant line, no-fin-ray/nfr in which homozygous mutant of adult fish fin ray development is largely reduced. Illumina RNAseq with 3 embryos each from mutants, siblings and the parental WT strain Hon9 (only 9 embryos as total) identified a mutation in the edaradd in a highly conserved C-terminal death domain.
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Cancer Institute (Key Laboratory of Cancer Prevention and Intervention, China National Ministry of Education), Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310000, China.
Activation of the stimulator of interferon genes (STING) pathway by cytosolic DNA leads to the activation of the transcription factors interferon regulatory factor 3 (IRF3) and nuclear factor κB (NF-κB). Although many viruses produce proteins that inhibit IRF3-dependent antiviral responses, some viruses produce proteins that inhibit STING-induced NF-κB activation without blocking IRF3 activation. Here, we found that STING-activated, NF-κB-dependent, and IRF3-independent innate immunity inhibited the replication of the DNA virus herpes simplex virus type 1 (HSV-1), the RNA virus coxsackievirus A16 (CV-A16), and the retrovirus HIV-1.
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