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Epigenetic Repression of Male Gametophyte- Specific Genes in the Arabidopsis Sporophyte

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Molecular Plant 2013年第4期6卷 1176-1186页

作者： Robert D. Hoffmann Michael G. Palmgren centre for Membrane Pumps in Cells and Disease--PUMPKIN Danish National Research Foundation Department of Plant and Environmental SciencesUniversity of Copenhagen Thorvaldsensvej 40 DK-1871 Frederiksberg Denmark

Tissue formation, the identity of cells, and the functions they fulfill, are results of gene regulation. The male gametophyte of plants, pollen, is outstanding in this respect as several hundred genes expressed in pollen are not expressed in the sporophyte. How pollen-specific genes are down-regulated in the sporophyte has yet to be established. In this study, we have performed a bioinformatics analysis of publicly available genome-wide epigenetics data of sev- eral sporophytic tissues. By combining this analysis with DNase ! footprinting data, we assessed means by which the repression of pollen-specific genes in the Arabidopsis sporophyte is conferred. Our findings show that, in seedlings, the majority of pollen-specific genes are associated with histone-3 marked by mono- or trimethylation of Lys-27 （H3K27me1/ H3K27me3）, both of which are repressive markers for gene expression in the sporophyte. Analysis of DNase footprint profiles of pollen-specific genes in the sporophyte displayed closed chromatin proximal to the start codon. We describe a model of two-staged gene regulation in which a lack of nucleosome-free regions in promoters and histone modifications in open reading frames repress pollen-specific genes in the sporophyte.

关键词： male gametophyte epigenetics gene repression DNase I footprinting transcription factors bioinformatics.

Pacemaker implantation in a patient with brugada and sick sinus syndrome

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World Journal of Cardiology 2013年第3期5卷 65-67页

作者： Bjarke Risgaard Henning Bundgaard Reza Jabbari Stig HaunsФ Bo Gregers Winkel Jacob Tfelt-Hansen the danish national research foundation centre for cardiac arrhythmia University of Copenhagen Laboratory of Molecular Cardiology Department of Cardiology The Heart Centre Copenhagen University Hospital Rigshospitalet

Brugada syndrome (BrS) is a rare and inherited primary arrhythmic syndrome characterized by ST-segment elevations in the right precordial leads (V1 -V3 ) with an increased risk of sudden cardiac death (SCD). arrhythmias in BrS are often nocturne, and brady-arrhythmias are often seen in patients with loss-of-function mutations in SCN5A . In this case-report we present a 75-year old woman referred to our outpatient clinic for inherited cardiac diseases for a familial clinical work-up. Since childhood she had suffered from dizziness, absence seizures, and countless Syncope's. In 2004 sick sinus syndrome was suspected and she wastreated with implantation of a pacemaker (PM) at another institution. An inherited cardiac disease was one day suddenly suspected, as the patient had a 61-year old brother who was diagnosed with symptomatic BrS, and treated with an implantable cardioverter defibrillator (ICD) after aborted SCD. A mutation screening revealed a SCN5A [S231CfsX251 (c.692-693delCA )] loss-of-function mutation not previously reported, and as a part of the cascade screening in relatives she was therefore referred to our clinic. In the 7 year period after PM implantation she had experienced no cardiac symptoms, although her electrocardiogram changes now were consistent with a BrS type 1 pattern. A genetic test confirmed that she had the same mutation in SCN5A as her brother. In this case-report we present a loss-of function mutation in SCN5A not previously associated with BrS nor presented in healthy controls. Sinus node dysfunction has previously been documented in patients with symptomatic BrS, which suggests it is not a rare concomitant. The only accepted treatment of BrS is today implantation of an ICD. In the future studies should evaluate if PM in some cases of symptomatic BrS can be used instead of ICDs in patients with a loss-of-function SCN5A

关键词： Brugada syndrome Pacemaker arrhythmias Sudden cardiac death

ECG is not a reliable predictor of sudden cardiac death in the general population

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World Journal of Cardiovascular Diseases 2013年第2期3卷 239-244页

作者： Juliane Theilade Redi Pecini Jacob L. Marott Gorm B. Jensen Copenhagen City Heart Study Bispebjerg Hospital Bispebjerg Denmark Department of Cardiology Copenhagen University Hospital Hvidovre Denmark Department of Cardiology The Heart Centre Copenhagen University Hospital—Rigshospitalet Copenhagen Denmark the danish national research foundation centre for cardiac arrhythmia (DARC) Copenhagen Denmark

Objectives: To determine the predictive value of the ECG for sudden death in the general population. Design: In the Copenhagen City Heart Study, a randomly selected population sample in Copenhagen, Denmarkhas been followed prospectively since 1976. From this population sample, we analyzed ECGs of individuals who had suffered sudden cardiac death (SCD) before the age of 50 years and compared them with ECGs of a randomly selected control individuals from the same population sample. Specific ECG signs that could point toward a condition associated with a risk of SCD were noted. Results: From a total of 18,974 individuals in the cohort, 207 had died at an age younger than 50 years. Among these, 24 persons with SCD were identified. The most prevalent ECG abnormality was QRS fragmentation. We found no ECGs with long or short QTc, Brugada sign or WPW. The prevalence of signs of left ventricular hyper-trophy, early repolarization, or fragmentation was not different from the prevalence of these signs in the control group. Conclusion: In the Copenhagen City Heart Study, the ECG failed to predict SCD in persons who died before the age of 50 years.

关键词： Sudden cardiac Death ECG Predictive Value of the ECG General Population Prediction of SCD arrhythmia Cardiomyopathy Ischemic Heart Disease Copenhagen City Heart Study Prospective

Intestinal microbiome changes in an infant with right atrial isomerism and recurrent necrotizing enterocolitis:A case report and review of literature

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World Journal of Clinical Cases 2022年第29期10卷 10583-10599页

作者： Aleksandra Kaplina Ekaterina Zaikova Artem Ivanov Yulia Volkova Tatiana Alkhova Vladimir Nikiforov Alexander Latypov Marina Khavkina Tatiana Fedoseeva Tatiana Pervunina Yulia Skorobogatova Svetlana Volkova Vladimir Ulyantsev Olga Kalinina Stanislav Sitkin Natalia Petrova research Laboratory of Physiology and Diseases of Newborns Almazov National Medical Research CentreSt.Petersburg 197341Russia research Laboratory of Autoimmune and Autoinflammatory Diseases Almazov National Medical Research CentreSt.Petersburg 197341Russia Vladimir Ulyantsev International Laboratory of Computer TechnologiesITMO UniversitySt.Petersburg 197101Russia Department of Cardiovascular Surgery for Children Almazov National Medical Research CentreSt.Petersburg 197341Russia Department of Neonatal Physiology with an ICU Ward Almazov National Medical Research CentreSt.Petersburg 197341Russia Pediatric cardiac Intensive Care Unit Almazov National Medical Research CentreSt.Petersburg 197341Russia Neonatal and Preterm Special Care Unit(2nd Stage Care) Almazov National Medical Research CentreSt.Petersburg 197341Russia Institute of Perinatology and Pediatrics Almazov National Medical Research CentreSt.Petersburg 197341Russia Express Laboratory of Perinatal centre Almazov National Medical Research CentreSt.Petersburg 197341Russia Clinical Diagnostic Laboratory Almazov National Medical Research CentreSt.Petersburg 197341Russia Epigenetics and Metagenomics Group Institute of Perinatology and PediatricsAlmazov National Medical Research CentreSt.Petersburg 197341Russia Department of Internal Diseases Gastroenterology and DieteticsNorth-Western State Medical University named after I.I.MechnikovSt.Petersburg 191015Russia

BACKGROUND Necrotizing enterocolitis(NEC)is a multifactorial disease that predominantly affects premature *** dysbiosis plays a critical role in NEC pathogenesis in premature *** main risk factor for NEC in term infants is mesenteric hypoperfusion associated with ductaldependent congenital heart disease(CHD)that eventually leads to intestinal *** incidence of NEC in neonates with critical CHD is 6.8%-13%.However,the role of the intestinal microbiome in NEC pathogenesis in infants with ductal-dependent CHD remains *** SUMMARY A male term neonate with right atrial isomerism underwent modified Blalock-Taussig shunt placement on the 14^(th)day of life and had persistent mesenteric hypoperfusion after *** patient had episodes of NEC stageⅡA on the 1^(st)and 28^(th)days after cardiac *** microbial composition was analyzed before and after cardiac surgery by sequencing region V4 of the 16S rRNA *** surgery,species belonging to genera Veillonella and Clostridia and class Gammaproteobacteria were detected,Bifidobacteriaceae showed a low *** first NEC episode was associated with postoperative hemodynamic instability,intestinal ischemiareperfusion injury during cardiopulmonary bypass,and a high abundance of Clostridium paraputrificum(Clostridium sensu stricto I)(56.1%).Antibacterial therapy after the first NEC episode resulted in increased abundance of Gammaproteobacteria,decreased abundance of Firmicutes,and low alpha *** changes in the microbial composition promoted the growth of Clostridium sensu strictoⅠ(72.0%)before the second NEC *** A high abundance of Clostridium sensu strictoⅠand mesenteric hypoperfusion may have contributed to NEC in the present case.

关键词： Necrotizing enterocolitis Congenital heart disease Ivemark syndrome Heterotaxy Right atrial isomerism Intestinal microbiome Case report

Plasma natriuretic peptides during supraventricular tachycardia: A study in patients with atrioventricular nodal reentry tachycardia

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World Journal of Cardiovascular Diseases 2013年第7期3卷 471-475页

作者： Redi Pecini Steen Pehrson Xu Chen Anna Margrethe Thøgersen Andreas Kjaer Jesper Hastrup Svendsen Department of Cardiology The Heart CentreRigshospitaletUniversity of CopenhagenCopenhagenDenmark Department of Cardiology Center for Cardiovascular ResearchÅrhus University HospitalAalborg HospitalAalborgDenmark Department of Clinical Physiology Nuclear Medicine and PET&Cluster for Molecular ImagingRigshospitaletUniversity of Co-penhagenCopenhagenDenmark the danish national research foundation centre for cardiac arrhythmia CopenhagenDenmark Department of Surgery and Medicine Faculty of Health SciencesUniversity of CopenhagenCopenhagenDenmark

Aims: To characterize the plasma levels of the atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in patients with atrioventricular nodal reentry tachycardia (AVNRT), we measured the plasma levels of these peptides before and during tachycardia. Methods: We included 10 consecutive patients scheduled for ablation of typical AVNRT without structural heart disease. Catheters were inserted in the femoral artery, femoral vein, and coronary sinus (CS) prior to the ablation procedure. Blood samples were drawn before and after 3 min of tachycardia to measure plasma levels of ANP and BNP. Right atrial pressure (RAP) was measured at baseline. Results: Of the 10 patients, in three patients it was not possible to induce tachycardia leaving a total of 7 patients available for analysis. Mean age of the seven included patients was 40 ± 12 years (mean ± SD), five were female. ANP levels increased significantly during tachycardia in the artery (p = 0.0009) and vein (p = 0.003), but only borderline in CS (p = 0.09). BNP levels did not change during tachycardia in any location. Conclusion: ANP levels measured in the peripheral circulation increased acutely during tachycardia due to AVNRT. BNP levels did not increase.

关键词： Atrioventricular Nodal Reentry Tachycardia Atrial Natriuretic Peptide Brain Natriuretic Peptide

Why Lake Taihu continues to be plagued with cyanobacterial blooms through 10 years(2007–2017) efforts

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Science Bulletin 2019年第6期64卷 354-356页

作者： Boqiang Qin Hans W.Paerl Justin D.Brookes Jianguo Liu Erik Jeppesen Guangwei Zhu Yunlin Zhang Hai Xu Kun Shi Jianming Deng State Key Laboratory for Lake Science and Environment Nanjing Institute of Geography & Limnology Chinese Academy of Sciences The University of North Carolina at Chapel Hill Institute of Marine Sciences College of Environment Hohai University Water research centre School of Biological Science the University of Adelaide Center for Systems Integration and Sustainability Department of Fisheries and Wildlife Michigan State University Sino-danish centre for Education and research Department of Bioscience and Arctic research centre Aarhus University

With the expansion of urban, industry, and agriculture after World War II, eutrophication firstly emerged as a major water quality threat in small water bodies [1]. As the increasing magnitudes and scales of nutrient pollution and habitat alteration, many of the world's large lakes exhibit symptoms of eutrophication, e.g., toxic cyanobacterial blooms, deoxygenation, and habitat loss.

关键词： With the expansion increasing magnitudes habitat loss

High Ductility and Toughness of a Micro-duplex Medium-Mn Steel in a Large Temperature Range from—196 ℃ to 200 ℃

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Journal of Iron and Steel research International 2015年第12期22卷 1126-1130页

作者： Si-lian CHEN Jun HU Xiao-dan ZHANG Han DONG Wen-quan CAO Central Iron and Steel research Institute School of Materials Science and Engineering Huazhong University of Science and Technology danish-Chinese centre for Nanometals Section for Materials Science and Advanced CharacterizationDepartment of Wind EnergyTechnical University of Denmark

A medium-Mn steel （0.2C5Mn） was processed by intercritical annealing at different temperatures （625 ℃ and 650 ℃ ）. An ultrafine-grained micro-duplex structure consisting of alternating austenite and ferrite laths was de- veloped by austenite reverse transformation （ART） during intercritical annealing after forging and hot rolling. Ultra- high ductility with a total elongation higher than 30% was achieved in the temperature range from -196 ℃ to 200 ℃, and high impact toughness no less than 200 J at -40 ℃ was obtained. Based on the analysis of microstructure and mechanical properties, it was found that the enhanced ductility was determined by the phase transformation effect of austenite （TRIP effect）, while the delayed ductile to brittle transition was controlled by austenite stability.

关键词： high strength high ductility intercritical annealing medium-Mn steel ultrafine grain size

Challenges and opportunities in improving left ventricular remodelling and clinical outcome following surgical and trans-catheter aortic valve replacement

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Frontiers of Medicine 2021年第3期15卷 416-437页

作者： Xu Yu Jin Mario Petrou Jiang Ting Hu Ed D Nicol John R Pepper Surgical Echo-Cardiology Services Oxford Heart CentreJohn Radcliffe HospitalOxford University Hospitals NHS Foundation TrustOxford OX39DUUK cardiac Surgical Physiology and Genomics Group Nuffield Division of Clinical Laboratory SciencesRadcliffe Department of MedicineUniversity of OxfordOxford OX39DUUK Department of cardiac Surgery Royal Brompton HospitalLondon SW36NPUK national Heart and Lung Institute Imperial College LondonLondon SW36LYUK NIHR Imperial Biomedical research centre London W21NYUK Department of Cardiology Royal Brompton HospitalLondon SW36NPUK

Over the last half century,surgical aortic valve replacement(SAVR)has evolved to offer a durable and efficient valve haemodynamically,with low procedural complications that allows favourable remodelling of left ventricular(LV)structure and *** latter has become more challenging among elderly patients,particularly following trans-catheter aortic valve implantation(TAVI).Precise understanding of myocardial adaptation to pressure and volume overloading and its responses to valve surgery requires comprehensive assessments from aortic valve energy loss,valvular-vascular impedance to myocardial activation,force-velocity relationship,and myocardial *** hypertrophy and myocardial fibrosis remains as the structural and morphological focus in this *** intervention in asymptomatic aortic stenosis or regurgitation along with individualised management of hypertension and atrial fibrillation is likely to improve patient *** pacing via the His-Purkinje system for conduction abnormalities,further reduction in para-valvular aortic regurgitation along with therapy of angiotensin receptor blockade will improve patient outcome by facilitating hypertrophy regression,LV coordinate contraction,and global vascular *** leaflet thromboses require anticoagulation while impaired access to coronary ostia risks future TAVI-in-TAVI or coronary *** comparable long-term durability and the resolution of TAVI related complications become available,SAVR remains the first choice for lower risk younger patients.

关键词： surgical aortic valve replacement trans-catheter aortic valve implantation left ventricular hypertrophy and fibrosis myocardial force-velocity relationship His-Purkinje pacing renin-angiotensin system inhibitors coronary access impairment

Reconfigurable photovoltaic effect for optoelectronic artificial synapse based on ferroelectric p-n junction

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Nano research 2021年第11期14卷 4328-4335页

作者： Yanrong Wang Feng Wang Zhenxing Wang Junjun Wang Jia Yang Yuyu Yao Ningning Li Marshet Getaye Sendeku Xueying Zhan Congxin Shan Jun He CAS Center for Excellence in Nanoscience CAS Key Laboratory of Nanosystem and Hierarchical FabricationNational Center for Nanoscience and TechnologyBeijing100190China Key Laboratory of Artificial Micro-and Nano-structures of Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan430072China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Sino-danish college University of Chinese Academy of SciencesBeijing100049China Sino-danish centre for Education and research Beijing100049China School of Physics and Engineering Zhengzhou UniversityZhengzhou450001China

Neuromorphic machine vision has attracted extensive attention on wide ***,both current and emerging strategies still suffer from power/time inefficiency,and/or low compatibility,complex device *** we demonstrate a driving-voltage-free optoelectronic synaptic device using non-volatile reconfigurable photovoltaic effect based on MoTe_(2)/α-In_(2)Se_(3) ferroelectric p-n *** function comes from the non-volatile reconfigurable built-in potential in the p-n junction that is related to the ferroelectric polarization inα-In_(2)Se_(3).Reconfigurable rectification behavior and photovoltaic effect are demonstrated ***,the figure-of-merits for photovoltaic effect like photoelectrical conversion efficiency non-volatilely increases more than one *** on this,retina synapse-like vision functions are *** short-term and long-term plasticity,as well as basic neuromorphic learning and memory rule are achieved without applying driving *** work highlights the potential of ferroelectric p-n junctions for enhanced solar cell and low-power optoelectronic synaptic device for neuromorphic machine vision.

关键词： ferroelectric p-n junction reconfigurable rectification reconfigurable PV effect optoelectronic synaptic devices