14,812 results match your criteria platelet-activating factor

Prolonged Exposure to Platelet Activating Factor Transforms Breast Epithelial Cells.

Front Genet 2021 25;12:634938. Epub 2021 Mar 25.

Department of Biology, Indian Institute of Science Education and Research, Pune, India.

Lipid species are known to have various biological functions owing to their structural differences, and each of them possesses a specific role to play depending upon their location and distribution in the cell. Some of these lipids interact with proteins on the cell membrane and acts as second messengers. The level of lipid mediators is generally maintained in the cell by feedback mechanisms; however, their improper degradation or enhanced production leads to their accumulation in the tumor microenvironment and disturbs the homeostasis of the cell. Read More

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Thrombotic Thrombocytopenia after ChAdOx1 nCov-19 Vaccination.

N Engl J Med 2021 Apr 9. Epub 2021 Apr 9.

From Institut für Immunologie und Transfusionsmedizin, Universitätsmedizin Greifswald, Greifswald (A.G., T.T.), and the Division of Safety of Medicinal Products and Medical Devices, Paul-Ehrlich-Institut (Federal Institute for Vaccines and Biomedicines), Langen (K.W.) - both in Germany; the Departments of Pathology and Molecular Medicine and of Medicine, McMaster University, Hamilton, ON, Canada (T.E.W.); and the Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna (P.A.K., S.E.).

Background: Several cases of unusual thrombotic events and thrombocytopenia have developed after vaccination with the recombinant adenoviral vector encoding the spike protein antigen of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (ChAdOx1 nCov-19, AstraZeneca). More data were needed on the pathogenesis of this unusual clotting disorder.

Methods: We assessed the clinical and laboratory features of 11 patients in Germany and Austria in whom thrombosis or thrombocytopenia had developed after vaccination with ChAdOx1 nCov-19. Read More

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The Exploration of Novel Pharmacophore Characteristics and Multidirectional Elucidation of Structure-Activity Relationship and Mechanism of Sesquiterpene Pyridine Alkaloids from Based on Computational Approaches.

Evid Based Complement Alternat Med 2021 24;2021:6676470. Epub 2021 Mar 24.

Chongqing Academy of Chinese Materia Medica, No. 34 Nanshan Road, Nan'an District, Chongqing 400065, China.

Sesquiterpene pyridine alkaloids are a large group of highly oxygenated sesquiterpenoids, which are characterized by a macrocyclic dilactone skeleton containing 2-(carboxyalkyl) nicotinic acid and dihydro--agarofuran sesquiterpenoid, and are believed to be the active and less toxic components of . In this study, 55 sesquiterpene pyridine alkaloids from were subjected to identification of pharmacophore characteristics and potential targets analysis. Our results revealed that the greatest structural difference of these compounds was in the pyridine ring and the pharmacophore model-5 (Pm-05) was the best model that consisted of three features including hydrogen bond acceptor (HBA), hydrogen bond donor (HBD), and hydrophobic (HY), especially hydrophobic group located in the pyridine ring. Read More

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Mechanisms of human drug-induced anaphylaxis.

J Allergy Clin Immunol 2021 Apr;147(4):1133-1142

Department "Auto-immunité et Hypersensibilités," DMU BioGeM, APHP, Hôpital Bichat, Paris, France; "Inflammation, Microbiome and Immunosurveillance" INSERM UMR 996, Faculté de Pharmacie, Université Paris-Saclay, Châtenay-Malabry, France. Electronic address:

Drug-induced anaphylaxis is a hyperacute reaction affecting multiple organs that can be of fatal consequence. Its incidence is increasing, consistent with a global increased sensitization to various allergens and drugs in the population. Few risk factors and mechanisms have been identified from human studies due to the rarity of anaphylactic events and their unpredictability. Read More

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Keratinocyte-derived microvesicle particles mediate Ultraviolet B radiation induced systemic immunosuppression.

J Clin Invest 2021 Apr 8. Epub 2021 Apr 8.

Boonshoft School of Medicine Wright State University, Dayton, United States of America.

A complete carcinogen, Ultraviolet B radiation (290-320 nm; UVB), is the major cause of skin cancer. UVB-induced systemic immunosuppression that contributes to photocarcinogenesis is due to the glycerophosphocholine-derived lipid mediator Platelet-activating factor. A major question in photobiology is how UVB radiation, which only absorbs appreciably in the epidermal layers of skin, can generate systemic effects. Read More

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Hymoins A-D: Two Pairs of Polyprenylated Acylphloroglucinols from and Their Light-Induced Transformation.

Org Lett 2021 Apr 5. Epub 2021 Apr 5.

State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, China.

Hymoins A-D (-), two pairs of light-induced transformative polyprenylated acylphloroglucinols with an unprecedented pentacyclic skeleton, were isolated from the flowers of . The first decarbonylative ring contraction of complex natural products was investigated by light irradiation. Their structures were elucidated by nuclear magnetic resonance analysis, X-ray crystallography, and electronic circular dichroism calculations. Read More

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Effect of MgCl and GdCl on ORAI1 Expression and Store-Operated Ca Entry in Megakaryocytes.

Int J Mol Sci 2021 Mar 24;22(7). Epub 2021 Mar 24.

Department of Vegetative and Clinical Physiology, Eberhard Karls University, 72074 Tübingen, Germany.

In chronic kidney disease, hyperphosphatemia upregulates the Ca channel ORAI and its activating Ca sensor STIM in megakaryocytes and platelets. ORAI1 and STIM1 accomplish store-operated Ca entry (SOCE) and play a key role in platelet activation. Signaling linking phosphate to upregulation of ORAI1 and STIM1 includes transcription factor NFAT5 and serum and glucocorticoid-inducible kinase SGK1. Read More

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Microvesicles in plasma reflect coronary flow reserve in patients with cardiovascular disease.

Am J Physiol Heart Circ Physiol 2021 Apr 2. Epub 2021 Apr 2.

Department of Cardiology, Clinical Sciences, Lund University, Lund, Sweden.

High levels of microvesicles (MVs), a type of extracellular vesicles, are detected in several pathological conditions. We investigated the connection between coronary flow reserve (CFR), a prognostic clinical parameter that reflects blood flow in the heart, with levels of MVs and their cargo, from plasma of cardiovascular patients. The PROFLOW study consists of 220 patients with prior myocardial infarction and measured CFR with transthoracic echocardiography. Read More

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Activation of Neutrophil Granulocytes by Platelet-Activating Factor Is Impaired During Experimental Sepsis.

Front Immunol 2021 16;12:642867. Epub 2021 Mar 16.

Institute of Clinical and Experimental Trauma Immunology, University Hospital of Ulm, Ulm, Germany.

Platelet-activating factor (PAF) is an important mediator of the systemic inflammatory response. In the case of sepsis, proper activation and function of neutrophils as the first line of cellular defense are based on a well-balanced physiological response. However, little is known about the role of PAF in cellular changes of neutrophils during sepsis. Read More

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New Insights Into the Pathologic Roles of the Platelet-Activating Factor System.

Front Endocrinol (Lausanne) 2021 15;12:624132. Epub 2021 Mar 15.

Department of Pharmacology & Toxicology, Boonshoft School of Medicine at Wright State University, Dayton, OH, United States.

Described almost 50 years ago, the glycerophosphocholine lipid mediator Platelet-activating factor (PAF) has been implicated in many pathologic processes. Indeed, elevated levels of PAF can be measured in response to almost every type of pathology involving inflammation and cell damage/death. In this review, we provide evidence for PAF involvement in pathologic processes, with focus on cancer, the nervous system, and in photobiology. Read More

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The ménage à trois of autophagy, lipid droplets and liver disease.

Autophagy 2021 Apr 2:1-24. Epub 2021 Apr 2.

Department of Cell Biology, University of Groningen, University Medical Center Groningen, AV Groningen, The Netherlands.

Autophagic pathways cross with lipid homeostasis and thus provide energy and essential building blocks that are indispensable for liver functions. Energy deficiencies are compensated by breaking down lipid droplets (LDs), intracellular organelles that store neutral lipids, in part by a selective type of autophagy, referred to as lipophagy. The process of lipophagy does not appear to be properly regulated in fatty liver diseases (FLDs), an important risk factor for the development of hepatocellular carcinomas (HCC). Read More

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Porphyromonas gingivalis enhances pneumococcal adhesion to human alveolar epithelial cells by increasing expression of host platelet-activating factor receptor.

FEBS Lett 2021 Mar 31. Epub 2021 Mar 31.

Department of Microbiology, Nihon University School of Dentistry, Tokyo, Japan.

Streptococcus pneumoniae causes pneumonia by infecting the alveolar epithelium via binding to host receptors, such as the platelet-activating factor receptor (PAFR). Although chronic periodontitis has been identified as a pneumonia risk factor, how periodontopathic bacteria cause pneumonia is not known. We found that S. Read More

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MicroRNA-212-5p and its target PAFAH1B2 suppress vascular proliferation and contraction via the downregulation of RhoA.

PLoS One 2021 24;16(3):e0249146. Epub 2021 Mar 24.

Heart Research Center of Chonnam National University Hospital, Gwangju, Republic of Korea.

Vascular remodeling and contraction contribute to the development of hypertension. We investigated the role of miR-212-5p and its downstream target in vascular smooth muscle cell (VSMC) proliferation, migration, and contraction. MicroRNA microarray and PCR analyses showed that miR-212-5p expression was increased with angiotensin II treatment in vivo and in vitro. Read More

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Platelet activation and aggregation in different centrifugal-flow left ventricular assist devices.

Platelets 2021 Mar 24:1-8. Epub 2021 Mar 24.

Department of Internal Medicine II, Medical University of Vienna, Vienna, Austria.

Left-ventricular assist devices (LVADs) improve outcomes in end-stage heart failure patients. Two centrifugal-flow LVAD systems are currently approved, HeartMate 3 (HM3) and Medtronic/Heartware HVAD (HVAD). Clinical findings suggest differences in thrombogenicity between both systems. Read More

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Drupin, a thrombin-like protease prompts platelet activation and aggregation through protease-activated receptors.

J Cell Biochem 2021 Mar 21. Epub 2021 Mar 21.

Department of Studies in Biochemistry, University of Mysore, Manasagangothri, Mysuru, Karnataka, India.

Hemostasis is a proteolytically regulated process that requires activation of platelets and the blood coagulation cascade upon vascular injury. Activated platelets create a thrombogenic environment and amplify the coagulation process. Plant latex proteases (PLPs) have been used as therapeutic components to treat various ailments by folk healers. Read More

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Vascular Permeability: Regulation Pathways and Role in Kidney Diseases.

Nephron 2021 Mar 19:1-14. Epub 2021 Mar 19.

Unité mixte Inserm - Sorbonne Université, UMR_S1155, Tenon Hospital, Paris, France.

Background: Vascular permeability (VP) is a fundamental aspect of vascular biology. A growing number of studies have revealed that many signalling pathways govern VP in both physiological and pathophysiological conditions. Furthermore, emerging evidence identifies VP alteration as a pivotal pathogenic factor in acute kidney injury, chronic kidney disease, diabetic kidney disease, and other proteinuric diseases. Read More

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PAFAH1B3 Expression Is Correlated With Gastric Cancer Cell Proliferation and Immune Infiltration.

Front Oncol 2021 25;11:591545. Epub 2021 Feb 25.

School of Medicine, Nankai University, Tianjin, China.

Background: Platelet activating factor acetylhydrolase 1b catalytic subunit 3 (PAFAH1B3) is associated with a variety of human diseases. However, its function in gastric cancer remains uncertain.

Methods: PAFAH1B3 expression was analyzed in The Cancer Genome Atlas (TCGA) and genotype-tissue expression pan-cancer data. Read More

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February 2021

TMEM119 facilitates ovarian cancer cell proliferation, invasion, and migration via the PDGFRB/PI3K/AKT signaling pathway.

J Transl Med 2021 Mar 17;19(1):111. Epub 2021 Mar 17.

Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, No. 36, Sanhao Street, Heping District, Shenyang, 110004, China.

Background: Ovarian cancer (OV) is the deadliest gynecological cancer. Transmembrane protein 119 (TMEM119) has been reported as oncogene in several human cancers. However, the function of TMEM119 in OV is still poorly known. Read More

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Pathogenicity and virulence of Japanese encephalitis virus: Neuroinflammation and neuronal cell damage.

Virulence 2021 12;12(1):968-980

Department of Preventive Veterinary Medicine, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi, P. R. China.

Thousands of human deaths occur annually due to Japanese encephalitis (JE), caused by Japanese encephalitis virus. During the virus infection of the central nervous system, reactive gliosis, uncontrolled inflammatory response, and neuronal cell death are considered as the characteristic features of JE. To date, no specific treatment has been approved to overcome JE, indicating a need for the development of novel therapies. Read More

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December 2021

Glioblastoma cell populations with distinct oncogenic programs release podoplanin as procoagulant extracellular vesicles.

Blood Adv 2021 Mar;5(6):1682-1694

Department of Experimental Medicine, McGill University, Montreal, QC, Canada.

Vascular anomalies, including local and peripheral thrombosis, are a hallmark of glioblastoma (GBM) and an aftermath of deregulation of the cancer cell genome and epigenome. Although the molecular effectors of these changes are poorly understood, the upregulation of podoplanin (PDPN) by cancer cells has recently been linked to an increased risk for venous thromboembolism (VTE) in GBM patients. Therefore, regulation of this platelet-activating protein by transforming events in cancer cells is of considerable interest. Read More

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Mutations in RASGRP2 gene identified in patients misdiagnosed as Glanzmann thrombasthenia patients.

Blood Cells Mol Dis 2021 Mar 4;89:102560. Epub 2021 Mar 4.

The Israeli National Hemophilia Center and Thrombosis Institute, Sheba Medical Center, Tel Hashomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Amalia Biron Research Institute of Thrombosis and Hemostasis, Sheba Medical Center, Tel Hashomer, and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel. Electronic address:

Introduction: Glanzmann thrombasthenia (GT) is a severe inherited platelet function disorder (IPFD), presenting with bleeding diathesis and impaired platelet aggregation, is caused by mutations in the genes ITGA2B or ITGB3.

Aim: We aimed to study the genetic cause of IPFD mimicking GT.

Methods: During 2017-2019, 16 patients were referred to our tertiary center with bleeding symptoms, impaired platelet aggregation and normal platelet count and size. Read More

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Segmental overgrowth and aneurysms due to mosaic PDGFRB p.(Tyr562Cys).

Am J Med Genet A 2021 May 8;185(5):1430-1436. Epub 2021 Mar 8.

Division of Medical Genetics, Department of Pediatrics, University of California, San Francisco, California, USA.

Activating variants in the platelet-derived growth factor receptor β gene (PDGFRB) have been associated with Kosaki overgrowth syndrome, infantile myofibromatosis, and Penttinen premature aging syndrome. A recently described phenotype with fusiform aneurysm has been associated with mosaic PDGFRB c.1685A > G p. Read More

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Beneficial Anti-Platelet and Anti-Inflammatory Properties of Irish Apple Juice and Cider Bioactives.

Foods 2021 Feb 12;10(2). Epub 2021 Feb 12.

Department of Biological Sciences, University of Limerick, V94 T9PX Limerick, Ireland.

Several bioactives from fruit juices and beverages like phenolics, nucleotides and polar lipids (PL) have exhibited anti-platelet cardio-protective properties. However, apple juice and cider lipid bioactives have not been evaluated so far. The aim of this study was to investigate the anti-platelet and anti-inflammatory effects and structure activity relationships of Irish apple juice and Real Irish cider lipid bioactives against the platelet-activating factor (PAF)- and adenosine diphosphate (ADP)-related thrombotic and inflammatory manifestations in human platelets. Read More

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February 2021

Interaction of Native- and Oxidized-Low-Density Lipoprotein with Human Estrogen Sulfotransferase.

Protein J 2021 Apr 4;40(2):192-204. Epub 2021 Mar 4.

Department of Pharmaceutical Health Science, Faculty of Pharmacy, Iryo Sosei University, 5-5-1, Chuodai-Iino, Iwaki, Fukushima, 970-8551, Japan.

Cytosolic estrogen sulfotransferase (SULT1E) mainly catalyzes the sulfate conjugation of estrogens, which decrease atherosclerosis progression. Recently we reported that a YKEG sequence in human SULT1E1 (hSULT1E1) corresponding to residues 61-64 can bind specifically to oxidized low-density lipoprotein (Ox-LDL), which plays a major role in the pathogenesis of atherosclerosis; its major oxidative lipid component lysophosphatidylcholine (LPC), and its structurally similar lipid, platelet-activating factor (PAF). In this study, we investigated the effect of Ox-LDL on the sulfating activity of hSULT1E1. Read More

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