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PAHs and their hydroxylated metabolites in the human fingernails from e-waste dismantlers: Implications for human non-invasive biomonitoring and exposure.

Environ Pollut 2021 Mar 31;283:117059. Epub 2021 Mar 31.

Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou, 510006, China; Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control, Key Laboratory of City Cluster Environmental Safety and Green Development, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China. Electronic address:

Non-invasive human biomonitoring methods using hair and fingernails as matrices are widely used to assess the exposure of organic contaminants. In this work, a total of 72 human fingernails were collected from workers and near-by residents from a typical electronic waste (e-waste) dismantling site, and were analyzed for human exposure to polycyclic aromatic hydrocarbons (PAHs) and their mono-hydroxyl metabolites (OH-PAHs). The concentrations of PAHs and OH-PAHs were obtained as 7. Read More

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Conformational Shifts of Stacked Heteroaromatics: Vacuum vs. Water Studied by Machine Learning.

Front Chem 2021 26;9:641610. Epub 2021 Mar 26.

Center of Molecular Biosciences Innsbruck, Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, Innsbruck, Austria.

Stacking interactions play a crucial role in drug design, as we can find aromatic cores or scaffolds in almost any available small molecule drug. To predict optimal binding geometries and enhance stacking interactions, usually high-level quantum mechanical calculations are performed. These calculations have two major drawbacks: they are very time consuming, and solvation can only be considered using implicit solvation. Read More

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Formation of Corrugated = 1 2D Tin Iodide Perovskites and Their Use as Lead-Free Solar Absorbers.

ACS Nano 2021 Apr 5. Epub 2021 Apr 5.

Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.

Major strides have been made in the development of materials and devices based around low-dimensional hybrid group 14 metal halide perovskites. Thus far, this work has mostly focused on compounds containing highly toxic Pb, with the analogous less toxic Sn materials being comparatively poorly evolved. In response, the study herein aims to (i) provide insight into the impact of templating cations upon the structure of = 1 2D tin iodide perovskites (where refers to the number of contiguous two-dimensional (2D) inorganic layers, , not separated by organic cations) and (ii) examine their potential as light absorbers for photovoltaic (PV) cells. Read More

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Septins in Infections: Focus on Viruses.

Pathogens 2021 Mar 2;10(3). Epub 2021 Mar 2.

Anatomy Unit, Department of Oncology, Microbiology and Immunology, Faculty of Science and Medicine, University of Fribourg, 1700 Fribourg, Switzerland.

Human septins comprise a family of 13 genes that encode conserved GTP-binding proteins. They form nonpolar complexes, which assemble into higher-order structures, such as bundles, scaffolding structures, or rings. Septins are counted among the cytoskeletal elements. Read More

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Preparation and Optimization of PEGylated Nano Graphene Oxide-Based Delivery System for Drugs with Different Molecular Structures Using Design of Experiment (DoE).

Molecules 2021 Mar 7;26(5). Epub 2021 Mar 7.

Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia.

Graphene oxide (GO), due to its 2D planar structure and favorable physical and chemical properties, has been used in different fields including drug delivery. This study aimed to investigate the impact of different process parameters on the average size of drug-loaded PEGylated nano graphene oxide (NGO-PEG) particles using design of experiment (DoE) and the loading of drugs with different molecular structures on an NGO-PEG-based delivery system. GO was prepared from graphite, processed using a sonication method, and functionalized using PEG 6000. Read More

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Piece of the puzzle: Remdesivir disassembles the multimeric SARS-CoV-2 RNA-dependent RNA polymerase complex.

Cell Biochem Biophys 2021 Apr 1. Epub 2021 Apr 1.

Molecular Bio-computation and Drug Design Laboratory, School of Health Sciences, University of KwaZulu-Natal, Westville Campus, Durban, 4001, South Africa.

The recently emerged SARS-like coronavirus (SARS-CoV-2) has continued to spread rapidly among humans with alarming upsurges in global mortality rates. A major key to tackling this virus is to disrupt its RNA replication process as previously reported for Remdesivir (Rem-P). In this study, we theorize, using computational simulations, novel mechanisms that may underlie the binding of Rem-P to SARS-CoV-2 RdRp-NSPs complex; a multimeric assembly that drives viral RNA replication in human hosts. Read More

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A preliminary study into the use of tree-ring and foliar geochemistry as bio-indicators for vehicular NO pollution in Malta.

Isotopes Environ Health Stud 2021 Mar 26:1-15. Epub 2021 Mar 26.

School of Earth and Environmental Sciences, University of St Andrews, St Andrews, UK.

Emissions from traffic over the past few decades have become a significant source of air pollution. Among the pollutants emitted are nitrogen oxides (NO), exposure to which can be detrimental to public health. Recent studies have shown that nitrogen (N) stable isotope ratios in tree-rings and foliage express a fingerprint of their major N source, making them appropriate for bio-monitoring purposes. Read More

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Environment impact and probabilistic health risks of PAHs in dusts surrounding an iron and steel enterprise.

Sci Rep 2021 Mar 24;11(1):6749. Epub 2021 Mar 24.

School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, Shandong, China.

Dust can be regarded as environmental medium that indicates the level and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) coming from different pollution sources. In this study, samples including road dust, roof dust, and bare soil near an iron and steel enterprise (ISE) in Laiwu city of North China were collected. To assess the environment impact, atmosphere particulates and one flue dust from a coking plant were simultaneously sampled. Read More

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Lignin Compounds to Monoaromatics: Selective Cleavage of C-O Bonds over Brominated Ruthenium Catalyst.

Angew Chem Int Ed Engl 2021 Mar 17. Epub 2021 Mar 17.

Lille University of Science and Technology, Unite de Catalyse et Chimie du Solide, Cité Scientifique, Bâtiment C3, 59650, Villeneuve-d'Ascq, FRANCE.

The cleavage of C-O linkages in aryl ethers in biomass-derived lignin compounds without hydrogenation of the aromatic rings is a major challenge for the production of sustainable mono-aromatics. Conventional strategies over the heterogeneous metal catalysts require the addition of homogeneous base additives causing environmental problems. Herein, we propose a heterogeneous Ru/C catalyst modified by Br atoms for the selective direct cleavage of C-O bonds in diphenyl ether without hydrogenation of aromatic rings reaching the yield of benzene and phenol as high as 90. Read More

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Limits and opportunities for miniaturising ultrasonic surgical devices based on a Langevin transducer.

IEEE Trans Ultrason Ferroelectr Freq Control 2021 Mar 10;PP. Epub 2021 Mar 10.

Minimally invasive surgery offers opportunities for reduced morbidities, faster post-operative recovery and reduced costs and is a major focus of surgical device innovation. For ultrasonic surgical devices, which offer benefits of high precision, low force and tissue selectivity in surgical procedures, there exist laparoscopic ultrasonic shears for minimally invasive surgeries that combine tissue cutting with vessel haemostasis and sealing functions. Another approach to laparoscopy that could enable new procedures and increase the sites of surgeries that could be reached by an ultrasonic device, involves integrating a miniature ultrasonic tool with a flexible surgical robot. Read More

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Flagellar arrangements in elongated peritrichous bacteria: bundle formation and swimming properties.

Eur Phys J E Soft Matter 2021 Mar 8;44(2):17. Epub 2021 Mar 8.

Theoretical Physics of Living Matter, Institute of Biological Information Processing and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA, 52425, Jülich, Germany.

The surface distribution of flagella in peritrichous bacterial cells has been traditionally assumed to be random. Recently, the presence of a regular grid-like pattern of basal bodies has been suggested. Experimentally, the manipulation of the anchoring points of flagella in the cell membrane is difficult, and thus, elucidation of the consequences of a particular pattern on bacterial locomotion is challenging. Read More

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Temperature-induced changes in the proteome of Pseudomonas aeruginosa during petroleum hydrocarbon degradation.

Arch Microbiol 2021 Mar 6. Epub 2021 Mar 6.

College of Chemistry and Chemical Engineering, Xi'an Shiyou University, Xi'an, People's Republic of China.

Petroleum hydrocarbon contaminants, which are among the most serious pollutants in the petroleum industry, can be degraded sufficiently by Pseudomonas aeruginosa. However, temperature-induced stress will severely inhibit this biodegradation. In this study, the proteome of P. Read More

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Exposure to Atmospheric Particulate Matter-Bound Polycyclic Aromatic Hydrocarbons and Their Health Effects: A Review.

Int J Environ Res Public Health 2021 Feb 23;18(4). Epub 2021 Feb 23.

Institute of Nature and Environmental Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.

Particulate matter (PM) is a major factor contributing to air quality deterioration that enters the atmosphere as a consequence of various natural and anthropogenic activities. In PM, polycyclic aromatic hydrocarbons (PAHs) represent a class of organic chemicals with at least two aromatic rings that are mainly directly emitted via the incomplete combustion of various organic materials. Numerous toxicological and epidemiological studies have proven adverse links between exposure to particulate matter-bound (PM-bound) PAHs and human health due to their carcinogenicity and mutagenicity. Read More

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February 2021

Progression of the late-stage divisome is unaffected by the depletion of the cytoplasmic FtsZ pool.

Commun Biol 2021 Mar 1;4(1):270. Epub 2021 Mar 1.

Department of Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Auf der Morgenstelle, Tübingen, Germany.

Cell division is a central and essential process in most bacteria, and also due to its complexity and highly coordinated nature, it has emerged as a promising new antibiotic target pathway in recent years. We have previously shown that ADEP antibiotics preferably induce the degradation of the major cell division protein FtsZ, thereby primarily leading to a depletion of the cytoplasmic FtsZ pool that is needed for treadmilling FtsZ rings. To further investigate the physiological consequences of ADEP treatment, we here studied the effect of ADEP on the different stages of the FtsZ ring in rod-shaped bacteria. Read More

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Warmer springs have increased the frequency and extension of late-frost defoliations in southern European beech forests.

Sci Total Environ 2021 Feb 13;775:145860. Epub 2021 Feb 13.

EiFAB-iuFOR, University of Valladolid, Campus Duques de Soria, 42004 Soria, Spain.

Climate change is increasing the frequency of extreme climate events, causing profound impacts on forest function and composition. Late frost defoliation (LFD) events, the loss of photosynthetic tissues due to low temperatures at the start of the growing season, might become more recurrent under future climate scenarios. Therefore, the detection of changes in late-frost risk in response to global change emerges as a high-priority research topic. Read More

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February 2021

Spatial-temporal variability of metal pollution across an industrial district, evidencing the environmental inequality in São Paulo.

Environ Pollut 2020 Aug 16;263(Pt A):114583. Epub 2020 Apr 16.

Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil; Instituto de Estudos Avançados, Universidade de São Paulo, São Paulo, Brazil. Electronic address:

Although air pollution decreased in some cities that shifted from an industrial to a service-based economy, and vehicular emission regulation became more restrictive, it is still a major risk factor for mortality worldwide. In central São Paulo, Brazil, air quality monitoring stations and tree-ring analyses revealed a decreasing trend in the concentrations of particulate matter and metals. Such trends, however, may not be observed in industrial districts located in the urban periphery, where the usual mobile sources may be combined with local stationary sources. Read More

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Antihypertensive and vasorelaxant effect of leucodin and achillin isolated from Achillea millefolium through calcium channel blockade and NO production: In vivo, functional ex vivo and in silico studies.

J Ethnopharmacol 2021 Jun 19;273:113948. Epub 2021 Feb 19.

Laboratorio de Farmacología, Depto. Ciencias de La Salud, D.C.B.S, Universidad Autónoma Metropolitana- Iztapalapa, Ciudad de México, 09340, Mexico.

Ethnopharmacological Relevance: Achillea millefolium L. (Asteraceae), known as yarrow (milenrama), is a plant used in Mexican traditional medicine for the treatment of hypertension, diabetes, and related diseases.

Aim: To determine the vasorelaxant and antihypertensive effect of A. Read More

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Disaggregation mechanism of prion amyloid for tweezer inhibitor.

Int J Biol Macromol 2021 Apr 16;176:510-519. Epub 2021 Feb 16.

State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, Department of Bioinformatics and Biostatistics, National Experimental Teaching Center for Life Sciences and Biotechnology, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Center for Bioinformation Technology, Shanghai 200235, China. Electronic address:

The aggregation of amyloid has been an important event in the pathology of amyloidogenicity. A number of small molecules have been designed for Amyloidosis treatment. Molecular tweezer CLR01, a potential drug for misfolded β-amyloids inhibition, was reportedly bind directly to Lysine residues and interrupt oligomerization. Read More

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Walking Speed Reliably Measures Clinically Significant Changes in Gait by Directional Deep Brain Stimulation.

Front Hum Neurosci 2020 29;14:618366. Epub 2021 Jan 29.

Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, United States.

Although deep brain stimulation (DBS) often improves levodopa-responsive gait symptoms, robust therapies for gait dysfunction from Parkinson's disease (PD) remain a major unmet need. Walking speed could represent a simple, integrated tool to assess DBS efficacy but is often not examined systematically or quantitatively during DBS programming. Here we investigate the reliability and functional significance of changes in gait by directional DBS in the subthalamic nucleus. Read More

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January 2021

Standardization of Kaempferia galanga L. rhizome and vasorelaxation effect of its key metabolite ethyl p-methoxycinnamate.

J Ethnopharmacol 2021 May 9;271:113911. Epub 2021 Feb 9.

Analytical Chemistry Department, CSIR-Central Institute of Medicinal and Aromatic Plants (CIMAP), Lucknow, 226 015, India. Electronic address:

Ethnopharmacological Relevance: Kaempferia galanga L. rhizome (KGR) is part of more than sixty-one Ayurvedic formulations and commonly known as 'Chandramula'. KGR is widely used in traditional Indian medicines to treat fever (jwar), rheumatism (Amavata), respiratory (Shwasa), hypertension (Vyanabala vaishamya) and cardiovascular disorders (Vyanavayu Dushtijanya Hrudrog). Read More

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On the Nature of Nucleobase Stacking in RNA: A Comprehensive Survey of Its Structural Variability and a Systematic Classification of Associated Interactions.

J Chem Inf Model 2021 Mar 11;61(3):1470-1480. Epub 2021 Feb 11.

Computational Biochemistry Laboratory, Department of Chemistry and Centre for Advanced Studies in Chemistry, Panjab University, Chandigarh 160014, India.

The astonishing diversity in folding patterns of RNA three-dimensional (3D) structures is crafted by myriads of noncovalent contacts, of which base pairing and stacking are the most prominent. A systematic and comprehensive classification and annotation of these interactions is necessary for a molecular-level understanding of their roles. However, unlike in the case of base pairing, where a widely accepted nomenclature and classification scheme exists in the public domain, currently available classification schemes for base-base stacking need major enhancements to comprehensively capture the necessary features underlying the rich stacking diversity in RNA. Read More

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Sexual Functioning, Satisfaction, and Well-Being Among Contraceptive Users: A Three-Month Assessment From the HER Salt Lake Contraceptive Initiative.

J Sex Res 2021 Feb 9:1-10. Epub 2021 Feb 9.

Department of Obstetrics and Gynecology, University of Utah.

Few large, longitudinal studies document multiple contraceptive methods' effects on sexual functioning, satisfaction, and well-being. We leveraged data from the HER Salt Lake Contraceptive Initiative, a prospective cohort study with patient surveys at baseline, one month, and three months. Surveys assessed bleeding changes, contraceptive-related side effects, sexual functioning and satisfaction, and perceptions of methods' impact on sexual well-being. Read More

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February 2021

Global tree intrinsic water use efficiency is enhanced by increased atmospheric CO and modulated by climate and plant functional types.

Proc Natl Acad Sci U S A 2021 Feb;118(7)

Department of Biology, West Virginia University, Morgantown, WV 26506.

We conducted a meta-analysis of carbon and oxygen isotopes from tree ring chronologies representing 34 species across 10 biomes to better understand the environmental drivers and physiological mechanisms leading to historical changes in tree intrinsic water use efficiency (iWUE), or the ratio of net photosynthesis () to stomatal conductance (), over the last century. We show a ∼40% increase in tree iWUE globally since 1901, coinciding with a ∼34% increase in atmospheric CO (C), although mean iWUE, and the rates of increase, varied across biomes and leaf and wood functional types. While C was a dominant environmental driver of iWUE, the effects of increasing C were modulated either positively or negatively by climate, including vapor pressure deficit (VPD), temperature, and precipitation, and by leaf and wood functional types. Read More

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February 2021

Defocus-dependent Thon-ring fading.

Ultramicroscopy 2021 Mar 21;222:113213. Epub 2021 Jan 21.

MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.

The brightness of modern Schottky field-emission guns can produce electron beams that have very high spatial coherence, especially for the weak-illumination conditions that are used for single-particle electron cryo-microscopy in structural biology. Even so, many users have observed defocus-dependent Thon-ring fading that has led them to restrict their data collection strategy to imaging with relatively small defocus values. In this paper, we reproduce the observation of defocus-dependent Thon-ring fading and produce a quantitative analysis and clear explanation of its causes. Read More

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Inhibitory Mechanism of the Isoflavone Derivative Genistein in the Human Ca3.3 Channel.

ACS Chem Neurosci 2021 02 28;12(4):651-659. Epub 2021 Jan 28.

School of Chemical Sciences, Meritorious Autonomous University of Puebla (BUAP), University City, Puebla 72570, Mexico.

Regulation of cellular excitability and oscillatory behavior of resting membrane potential in nerve cells are largely mediated by the low-voltage activated T-type calcium channels. This calcium channel family is constituted by three isoforms, namely, Ca3.1, Ca3. Read More

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February 2021

Predictive Rules of Efflux Inhibition and Avoidance in Pseudomonas aeruginosa.

mBio 2021 01 19;12(1). Epub 2021 Jan 19.

Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma, USA

Antibiotic-resistant bacteria rapidly spread in clinical and natural environments and challenge our modern lifestyle. A major component of defense against antibiotics in Gram-negative bacteria is a drug permeation barrier created by active efflux across the outer membrane. We identified molecular determinants defining the propensity of small peptidomimetic molecules to avoid and inhibit efflux pumps in , a human pathogen notorious for its antibiotic resistance. Read More

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January 2021

The Presence of Cholesteryl Ester Transfer Protein (CETP) in Endothelial Cells Generates Vascular Oxidative Stress and Endothelial Dysfunction.

Biomolecules 2021 Jan 7;11(1). Epub 2021 Jan 7.

Department of Structural and Functional Biology, Institute of Biology, State University of Campinas, Campinas 13083-970, Brazil.

Endothelial dysfunction precedes atherosclerosis and is an independent predictor of cardiovascular events. Cholesterol levels and oxidative stress are key contributors to endothelial damage, whereas high levels of plasma high-density lipoproteins (HDL) could prevent it. Cholesteryl ester transfer protein (CETP) is one of the most potent endogenous negative regulators of HDL-cholesterol. Read More

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January 2021

Glucagon, insulin, adrenocorticotropic hormone, and cortisol in response to carbohydrates and fasting in healthy neonatal foals.

J Vet Intern Med 2021 Jan 7;35(1):550-559. Epub 2021 Jan 7.

Department of Veterinary Clinical Sciences, The Ohio State University College of Veterinary Medicine.

Background: The endocrine pancreas and hypothalamic-pituitary-adrenal axis (HPAA) are central to energy homeostasis, but information on their dynamics in response to energy challenges in healthy newborn foals is lacking.

Objectives: To evaluate glucagon, insulin, ACTH, and cortisol response to fasting and carbohydrate administration in healthy foals.

Animals: Twenty-two healthy Standardbred foals ≤4 days of age. Read More

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January 2021

Adsorption of Organic Compounds by Biomass Chars: Direct Role of Aromatic Condensation (Ring Cluster Size) Revealed by Experimental and Theoretical Studies.

Environ Sci Technol 2021 Feb 7;55(3):1594-1603. Epub 2021 Jan 7.

School of Environment and Energy, South China University of Technology, Guangzhou 510006, P. R. China.

Biomass chars are a major component of the soil environmental black carbon pool and prepared forms are a potentially useful tool in remediation. A function critical to the roles of both environmental and prepared chars is sorption of organic compounds. Char properties known to control sorption include surface area, porosity, functional group composition, and percent aromatic carbon. Read More

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February 2021

ERK1/2 inhibition reduces vascular calcification by activating miR-126-3p-DKK1/LRP6 pathway.

Theranostics 2021 1;11(3):1129-1146. Epub 2021 Jan 1.

Key Laboratory of Metabolism and Regulation for Major Diseases of Anhui Higher Education Institutes, Hefei University of Technology, Hefei, China.

: Vascular microcalcification increases the risk of rupture of vulnerable atherosclerotic lesions. Inhibition of ERK1/2 reduces atherosclerosis in animal models while its role in vascular calcification and the underlying mechanisms remains incompletely understood. Levels of activated ERK1/2, DKK1, LRP6 and BMP2 in human calcific aortic valves were determined. Read More

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January 2021