57,216 results match your criteria channel activity

Probing the role of Val228 on the catalytic activity of Scytalidium catalase.

Biochim Biophys Acta Proteins Proteom 2021 Apr 19:140662. Epub 2021 Apr 19.

Department of Biology, Kocaeli University, Umuttepe, Kocaeli 41380, Turkey. Electronic address:

Scytalidium catalase is a homotetramer including heme d in each subunit. Its primary function is the dismutation of HO to water and oxygen, but it is also able to oxidase various small organic compounds including catechol and phenol. The crystal structure of Scytalidium catalase reveals the presence of three linked channels providing access to the exterior like other catalases reported so far. Read More

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Structural insights into the mechanisms and pharmacology of K potassium channels.

J Mol Biol 2021 Apr 19:166995. Epub 2021 Apr 19.

Cardiovascular Research Institute; Departments of Biochemistry and Biophysics, and Cellular and Molecular Pharmacology; California Institute for Quantitative Biomedical Research; Kavli Institute for Fundamental Neuroscience University of California, San Francisco, California 93858-2330 USA; Molecular Biophysics and Integrated Bio-imaging Division Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA. Electronic address:

Leak currents, defined as voltage and time independent flows of ions across cell membranes, are central to cellular electrical excitability control. The K (KCNK) potassium channel class comprises an ion channel family that produces potassium leak currents that oppose excitation and stabilize the resting membrane potential in cells in the brain, cardiovascular system, immune system, and sensory organs. Due to their widespread tissue distribution, Ks contribute to many physiological and pathophysiological processes including anesthesia, pain, arrythmias, ischemia, hypertension, migraine, intraocular pressure regulation, and lung injury responses. Read More

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EPA and DHA differentially modulate membrane elasticity in the presence of cholesterol.

Biophys J 2021 Apr 19. Epub 2021 Apr 19.

Department of Biomedical Engineering, Northwestern University, Evanston, IL 60657, USA; Center for Synthetic Biology, Northwestern University, Evanston, IL 60657, USA. Electronic address:

Polyunsaturated fatty acids (PUFAs) modify the activity of a wide range of membrane proteins and are increasingly hypothesized to modulate protein activity by indirectly altering membrane physical properties. Among the various physical properties affected by PUFAs, the membrane area expansion modulus (K), which measures membrane strain in response to applied force, is expected to be a significant controller of channel activity. Yet the impact of PUFAs on membrane K has not been measured previously. Read More

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Photosynthesis in Arabidopsis Is Unaffected by the Function of the Vacuolar K+ Channel TPK3.

Plant Physiol 2019 Jun;180(3):1322-1335

Plant Physiology, School of Biological Sciences, Washington State University, Pullman, Washington 99164-4236.

Photosynthesis is limited by the slow relaxation of nonphotochemical quenching, which primarily dissipates excess absorbed light energy as heat. Because the heat dissipation process is proportional to light-driven thylakoid lumen acidification, manipulating thylakoid ion and proton flux via transport proteins could improve photosynthesis. However, an important aspect of the current understanding of the thylakoid ion transportome is inaccurate. Read More

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Uniform decoration of UiO-66-NH nanooctahedra on TiO electrospun nanofibers for enhancing photocatalytic H production based on multi-step interfacial charge transfer.

Dalton Trans 2021 Apr 22. Epub 2021 Apr 22.

Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission, Key Laboratory of Photosensitive Materials and Devices of Liaoning Province, School of Physics and Materials Engineering, Dalian Nationalities University, 18 Liaohe West Road, Dalian 116600, P. R. China..

Metal-organic framework (MOF) materials have been extensively incorporated with inorganic semiconductor photocatalysts to improve their photocatalytic activity through an efficient charge transfer process across their heterointerface. In this work, octahedral UiO-66-NH2 MOFs with edge-lengths of 110-330 nm are uniformly decorated on the surface of TiO2 electrospun nanofibers by a traditional solvothermal method combined with activation pretreatment. Before the solvothermal growth of UiO-66-NH2, the TiO2 electrospun nanofibers were activated in NaOH solution to etch the TiO2 surface for allowing the exposure of lattice oxygen. Read More

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Macrophage depletion in stellate ganglia alleviates cardiac sympathetic overactivation and ventricular arrhythmogenesis by attenuating neuroinflammation in heart failure.

Basic Res Cardiol 2021 Apr 21;116(1):28. Epub 2021 Apr 21.

Department of Emergency Medicine, University of Nebraska Medical Center, Omaha, NE, 68198, USA.

Cardiac sympathetic overactivation is involved in arrhythmogenesis in patients with chronic heart failure (CHF). Inflammatory infiltration in the stellate ganglion (SG) is a critical factor for cardiac sympathoexcitation in patients with ventricular arrhythmias. This study aims to investigate if macrophage depletion in SGs decreases cardiac sympathetic overactivation and ventricular arrhythmogenesis in CHF. Read More

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Mapping the expression of transient receptor potential channels across murine placental development.

Cell Mol Life Sci 2021 Apr 21. Epub 2021 Apr 21.

Laboratory of Endometrium, Endometriosis and Reproductive Medicine, Department of Development and Regeneration, KU Leuven, Herestraat 49, Box 611, 3000, Leuven, Belgium.

Transient receptor potential (TRP) channels play prominent roles in ion homeostasis by their ability to control cation influx. Mouse placentation is governed by the processes of trophoblast proliferation, invasion, differentiation, and fusion, all of which require calcium signaling. Although certain TRP channels have been shown to contribute to maternal-fetal transport of magnesium and calcium, a role for TRP channels in specific trophoblast functions has been disregarded. Read More

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Italian Cardiological Guidelines (COCIS) for Competitive Sport Eligibility in athletes with heart disease: update 2020.

J Cardiovasc Med (Hagerstown) 2021 Apr 20. Epub 2021 Apr 20.

Division of Cardiology, Hospital 'P. Pederzoli', Peschiera del Garda, VR San Antonio Hospital, San Daniele del Friuli, UD Cardiology Unit, Policlinico Casilino, Rome Department of Cardiac, Thoracic and Vascular Sciences, University of Padova, Padua Institute of Sport Medicine and Science, Rome Referral Center for Cardiomyopathies, Careggi University Hospital, Florence Division of Cardiology, San Filippo Neri Hospital, Rome Department of Cardiothoracic Sciences, Monaldi Hospital, Second University of Naples, Naples Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila Cardiovascular Center, ASUITS, Maggiore Hospital, Trieste Sports Medicine Unit, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome Sports Medicine and Cardiovascular Rehabilitation Unit, Cardiovascular Department, PF Calvi Hospital, Noale, Venice Interventional Cardiology Unit, S. Maria Nuova Hospital, Reggio Emilia Ospedale Maggiore Di Crema, Crema Cardiology Unit, Villa Verde Hospital, Taranto Department of Cardiology, Carpi Hospital, Carpi Cardiology, Department of Life, Health and Environmental Sciences|, University of L'Aquila, L'Aquila Department of Cardiology, University of Rome 'Tor Vergata', Rome Center for Sports Medicine, Treviso Unit of Grown-up Congenital Heart Disease, Monaldi Hospital, Naples Cardiovascular Department, Azienda Sanitaria Universitaria Integrata, University of Trieste (ASUITS), Trieste, Italy.

Since 1989, SIC Sport and a FMSI, in partnership with leading Italian Cardiological Scientific Associations (ANCE, ANMCO and SIC) have produced Cardiological Guidelines for Completive Sports Eligibility for athletes with heart disease (COCIS -- 1989, 1995, 2003, 2009 and 2017). The English version of the Italian Cardiological Guidelines for Competitive Sports Eligibility for athletes with heart disease was published in 2013 in this Journal. This publication is an update with respect to the document previously published in English in 2013. Read More

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Role of pirfenidone in TGF-β pathways and other inflammatory pathways in acute respiratory syndrome coronavirus 2 (SARS-Cov-2) infection: a theoretical perspective.

Pharmacol Rep 2021 Apr 21. Epub 2021 Apr 21.

Al-Ameen College of Pharmacy, Rajiv Gandhi University of Health Sciences, Bangalore, India.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes pulmonary injury or multiple-organ injury by various pathological pathways. Transforming growth factor-beta (TGF-β) is a key factor that is released during SARS-CoV-2 infection. TGF-β, by internalization of the epithelial sodium channel (ENaC), suppresses the anti-oxidant system, downregulates the cystic fibrosis transmembrane conductance regulator (CFTR), and activates the plasminogen activator inhibitor 1 (PAI-1) and nuclear factor-kappa-light-chain-enhancer of activated B cells (NF-kB). Read More

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In vitro antiviral activity of the anti-HCV drugs daclatasvir and sofosbuvir against SARS-CoV-2, the aetiological agent of COVID-19.

J Antimicrob Chemother 2021 Apr 21. Epub 2021 Apr 21.

Laboratório de Imunofarmacologia, Instituto Oswaldo Cruz (IOC), Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, RJ, Brazil.

Background: Current approaches of drug repurposing against COVID-19 have not proven overwhelmingly successful and the SARS-CoV-2 pandemic continues to cause major global mortality. SARS-CoV-2 nsp12, its RNA polymerase, shares homology in the nucleotide uptake channel with the HCV orthologue enzyme NS5B. Besides, HCV enzyme NS5A has pleiotropic activities, such as RNA binding, that are shared with various SARS-CoV-2 proteins. Read More

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Caveolar peroxynitrite formation impairs endothelial TRPV4 channels and elevates pulmonary arterial pressure in pulmonary hypertension.

Proc Natl Acad Sci U S A 2021 Apr;118(17)

Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, VA 22908;

Recent studies have focused on the contribution of capillary endothelial TRPV4 channels to pulmonary pathologies, including lung edema and lung injury. However, in pulmonary hypertension (PH), small pulmonary arteries are the focus of the pathology, and endothelial TRPV4 channels in this crucial anatomy remain unexplored in PH. Here, we provide evidence that TRPV4 channels in endothelial cell caveolae maintain a low pulmonary arterial pressure under normal conditions. Read More

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Cortical haemodynamic response during the verbal fluency task in patients with bipolar disorder and borderline personality disorder: a preliminary functional near-infrared spectroscopy study.

BMC Psychiatry 2021 Apr 20;21(1):201. Epub 2021 Apr 20.

Institute for Health Innovation and Technology (iHealthtech), National University of Singapore, Singapore, 117599, Singapore.

Background: Functional near-infrared spectroscopy (fNIRS) is an emerging neuroimaging modality that provides a direct and quantitative assessment of cortical haemodynamic response during a cognitive task. It may be used to identify neurophysiological differences between psychiatric disorders with overlapping symptoms, such as bipolar disorder (BD) and borderline personality disorder (BPD). Hence, this preliminary study aimed to compare the cerebral haemodynamic function of healthy controls (HC), patients with BD and patients with BPD. Read More

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PcALF5 inhibits the proliferation of microbiota by binding to RPS4 and MscL of E. coli.

Dev Comp Immunol 2021 Apr 17:104106. Epub 2021 Apr 17.

College of Fisheries, Huazhong Agricultural University, Wuhan, 430070, China; Shandong Provincial Key Laboratory of Animal Biotechnology and Disease Control and Prevention, College of Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, 271018, China. Electronic address:

Antimicrobial peptides (AMPs), most of which are small proteins, are necessary for innate immunity against pathogens. Anti-lipopolysaccharide factor (ALF) with a conserved lipopolysaccharide binding domain (LBD) can bind to lipopolysaccharide (LPS) and neutralize LPS activity. The antibacterial mechanism of ALF, especially its role in bacteria, needs to be further investigated. Read More

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Ion channel regulation in endothelial function - The key role of dietary polyunsatured fatty acids for TRPV4 activity.

Cardiovasc Res 2021 Apr 20. Epub 2021 Apr 20.

Institute of Cardiovascular Research and Sport Medicine, German Sport University Cologne.

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Interaction between miRNA-155 targeting neuronal pacemaker ion channels and release of amino acid transmitters during cerebral ischemia.

Eur Rev Med Pharmacol Sci 2021 Apr;25(7):3007-3014

Department of Neurology, Qingdao Hospital of Traditional Chinese Medicine (Qingdao Hiser Hospital), Qingdao, Shandong, China.

Objective: Cerebral hemorrhage can cause hemorrhagic stroke, leading to severe brain damage. MiRNA-155 is closely related to the development of stroke. However, the regulatory mechanism of miRNA-155 during cerebral ischemia has not yet been elucidated. Read More

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Emerging Role of PD-1 in the Central Nervous System and Brain Diseases.

Neurosci Bull 2021 Apr 20. Epub 2021 Apr 20.

Department of Anesthesiology, Duke University Medical Center, Durham, 27710, USA.

Programmed cell death protein 1 (PD-1) is an immune checkpoint modulator and a major target of immunotherapy as anti-PD-1 monoclonal antibodies have demonstrated remarkable efficacy in cancer treatment. Accumulating evidence suggests an important role of PD-1 in the central nervous system (CNS). PD-1 has been implicated in CNS disorders such as brain tumors, Alzheimer's disease, ischemic stroke, spinal cord injury, multiple sclerosis, cognitive function, and pain. Read More

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Identification of herbal components as TRPA1 agonists and TRPM8 antagonists.

J Nat Med 2021 Apr 20. Epub 2021 Apr 20.

Tsumura Kampo Research Laboratories, Kampo Research and Development Division, Tsumura & Co, 3586 Yoshiwara, Ami-machi, Inashiki-gun, Ibaraki, 300-1192, Japan.

Transient receptor potential (TRP) channels are non-selective cation channels that are implicated in analgesia, bowel motility, wound healing, thermoregulation, vasodilation and voiding dysfunction. Many natural products have been reported to affect the activity of TRP channels. We hypothesize that numerous traditional herbal medicines (THMs) might exert their pharmacological activity through modulating the activity of TRP channels. Read More

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Flavonoids increase melanin production and reduce proliferation, migration and invasion of melanoma cells by blocking endolysosomal/melanosomal TPC2.

Sci Rep 2021 Apr 19;11(1):8515. Epub 2021 Apr 19.

Walther Straub Institute of Pharmacology and Toxicology, Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany.

Two-pore channel 2 (TPC2) resides in endolysosomal membranes but also in lysosome-related organelles such as the melanin producing melanosomes. Gain-of-function polymorphisms in hTPC2 are associated with decreased melanin production and blond hair color. Vice versa genetic ablation of TPC2 increases melanin production. Read More

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PIP corrects cerebral blood flow deficits in small vessel disease by rescuing capillary Kir2.1 activity.

Proc Natl Acad Sci U S A 2021 Apr;118(17)

Department of Pharmacology, Larner College of Medicine, University of Vermont, Burlington, VT 05405;

Cerebral small vessel diseases (SVDs) are a central link between stroke and dementia-two comorbidities without specific treatments. Despite the emerging consensus that SVDs are initiated in the endothelium, the early mechanisms remain largely unknown. Deficits in on-demand delivery of blood to active brain regions (functional hyperemia) are early manifestations of the underlying pathogenesis. Read More

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Heterotrimeric G-proteins in plant cell signaling.

P A Millner

New Phytol 2001 Jul;151(1):165-174

School of Biochemistry and Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.

Heterotrimeric G-proteins, which couple cell surface receptors with internal effectors, are evident in all eukaryotes. Their operation involves receptor activation, GTP/GDP exchange and modulation of effector activity; deactivation occurs by an intrinsic GTPase activity. Structurally, G-proteins comprise three dissimilar subunits; Gα, Gβ and Gγ. Read More

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Nimodipine inhibits intestinal and aortic smooth muscle contraction by regulating Ca-activated Cl channels.

Toxicol Appl Pharmacol 2021 Apr 16:115543. Epub 2021 Apr 16.

Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Sciences, Liaoning Normal University, Dalian 116000, PR China. Electronic address:

Nimodipine is a clinically used dihydropyridine L-type calcium channel antagonist that effectively inhibits transmembrane Ca influx following the depolarization of smooth muscle cells, but the detailed effect on smooth muscle contraction is not fully understood. Ca-activated Cl channels (CaCCs) in vascular smooth muscle cells (VSMCs) may regulate vascular contractility. We found that nimodipine can inhibit transmembrane protein 16A (TMEM16A) activity in a concentration-dependent manner by cell-based fluorescence-quenching assay and short-circuit current analysis, with an IC value of ~5 μM. Read More

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Pairing of neonatal phencyclidine exposure and acute adolescent stress in male rats as a novel developmental model of schizophrenia.

Behav Brain Res 2021 Apr 16:113308. Epub 2021 Apr 16.

Department of Cell Biology and Anatomy, New York Medical College, Valhalla, NY, 10595, United States. Electronic address:

Improved understanding of the neurophysiological and neurochemical mechanisms underlying schizophrenia is essential for the identification of biological markers and developing new therapeutic targets. The development of behaviorally faithful, predictive animal models is crucial to this endeavor. We have developed a novel two-hit paradigm designed to recapitulate in rodents the developmental process leading to appearance of human schizophrenia symptomatology. Read More

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Why do platelets express K channels?

Platelets 2021 Apr 19:1-8. Epub 2021 Apr 19.

Department of Molecular and Cellular Biology, University of Leicester, Leicester, UK.

Potassium ions have widespread roles in cellular homeostasis and activation as a consequence of their large outward concentration gradient across the surface membrane and ability to rapidly move through K-selective ion channels. In platelets, the predominant K channels include the voltage-gated K channel Kv1.3, and the intermediate conductance Ca-activated K channel KCa3. Read More

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Involvement of TRPC5 channels, inwardly rectifying K channels, PLCβ and PIP in vasopressin-mediated excitation of medial central amygdala neurons.

J Physiol 2021 Apr 19. Epub 2021 Apr 19.

Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND58203, USA.

Key Points: Activation of V vasopressin receptors facilitates neuronal excitability in the medial nucleus of central amygdala (CeM) V receptor activation excites about 80% CeM neurons by opening a cationic conductance and about 20% CeM neurons by suppressing an inwardly rectifying K (Kir) channels The cationic conductance activated by V receptors is identified as TRPC5 channels PLCβ-mediated depletion of PIP is involved in V receptor-elicited excitation of CeM neurons Intracellular Ca release and PKC are unnecessary for V receptor-mediated excitation of CeM neurons ABSTRACT: Arginine vasopressin (AVP) serves as a hormone in the periphery to modulate water homeostasis and a neuromodulator in the brain to regulate a diverse range of functions including anxiety, social behaviors, cognitive activities and nociception. The amygdala is an essential brain region involved in modulating defensive and appetitive behaviors, pain, and alcohol use disorders. Whereas activation of V receptors in the medial nucleus of the central amygdala (CeM) increases neuronal excitability, the involved ionic and signaling mechanisms have not been determined. Read More

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Potassium ions promote hexokinase-II dependent glycolysis.

iScience 2021 Apr 22;24(4):102346. Epub 2021 Mar 22.

Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, Neue Stiftingtalstraße 6/6, 8010 Graz, Austria.

High expression levels of mitochondria-associated hexokinase-II (HKII) represent a hallmark of metabolically highly active cells such as fast proliferating cancer cells. Typically, the enzyme provides a crucial metabolic switch towards aerobic glycolysis. By imaging metabolic activities on the single-cell level with genetically encoded fluorescent biosensors, we here demonstrate that HKII activity requires intracellular K. Read More

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Toward Predicting Motion Sickness Using Virtual Reality and a Moving Platform Assessing Brain, Muscles, and Heart Signals.

Front Bioeng Biotechnol 2021 1;9:635661. Epub 2021 Apr 1.

Institute of Biomedical and Neural Engineering, Reykjavik University, Reykjavík, Iceland.

Motion sickness (MS) and postural control (PC) conditions are common complaints among those who passively travel. Many theories explaining a probable cause for MS have been proposed but the most prominent is the sensory conflict theory, stating that a mismatch between vestibular and visual signals causes MS. Few measurements have been made to understand and quantify the interplay between muscle activation, brain activity, and heart behavior during this condition. Read More

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CRISPR/Cas9-Mediated α-ENaC Knockout in a Murine Pancreatic β-Cell Line.

Front Genet 2021 1;12:664799. Epub 2021 Apr 1.

Department of Pathophysiology, Nanjing Medical University, Nanjing, China.

Many ion channels participate in controlling insulin synthesis and secretion of pancreatic β-cells. Epithelial sodium channel (ENaC) expressed in human pancreatic tissue, but the biological role of ENaC in pancreatic β-cells is still unclear. Here, we applied the CRISPR/Cas9 gene editing technique to knockout α-ENaC gene in a murine pancreatic β-cell line (MIN6 cell). Read More

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Deficiency of voltage-gated proton channel Hv1 aggravates ovalbumin-induced allergic lung asthma in mice.

Int Immunopharmacol 2021 Apr 15;96:107640. Epub 2021 Apr 15.

Department of Biophysics, School of Physical Science, The Key Laboratory of Bioactive Materials, Ministry of Education, Nankai University, Tianjin 300071, China; Qilu Institute of Technology, Shandong 250200, P. R. China. Electronic address:

Asthma is a chronic airway inflammation that caused by many factors. The voltage-gated proton channel Hv1 has been proposed to extrude excessive protons produced by NADPH oxidase (NOX) from cytosol to maintain its activity during respiratory bursts. Here, we showed that loss of Hv1 aggravates ovalbumin (OVA)-induced allergic lung asthma in mice. Read More

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An AIS-based emission inventory and the impact on air quality in Tianjin port based on localized emission factors.

Sci Total Environ 2021 Apr 6;783:146869. Epub 2021 Apr 6.

Tianjin Key Laboratory of Urban Transport Emission Research & State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China. Electronic address:

Ship pollution has become a hot global issue. This study established a basic information database of Tianjin Port ship emissions and used it to screen representative ship types and perform real-world ship measurements by a portable emission measurement system (PEMS), which generated localized emission factors. The results show that the localized emission factors are significantly higher than those recommended in recommended in Chinese guidelines, which will lead to lower calculation results of the previous inventory. Read More

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Determinants of cardiac structure in frail and sarcopenic elderly adults.

Exp Gerontol 2021 Apr 14;150:111351. Epub 2021 Apr 14.

Department of Medicine and Surgery, University Medical School of Parma, Parma, Italy; University-Hospital of Parma, Parma, Italy; Geriatric Clinic Unit, University-Hospital of Parma, Parma, Italy.

Background: Cardiac structure and function change with age. The higher prevalence of left ventricular hypertrophy (LVH) with concentric remodeling is indicative of a typical geometric pattern of aging associated with a higher cardiovascular (CV) risk and diseases. The recent associations found between low left ventricular and skeletal mass in older patients with frailty and sarcopenia have raised great interest in investigating cardiac characteristics and determinants of left ventricular mass (LVM) in this population. Read More

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