305 results match your criteria separation perturbed

Solution structure of deglycosylated human IgG1 shows the role of C2 glycans in its conformation.

Biophys J 2021 Mar 4. Epub 2021 Mar 4.

Department of Structural and Molecular Biology, Division of Biosciences, University College London, London, United Kingdom. Electronic address:

The human immunoglobulin G (IgG) class is the most prevalent antibody in serum, with the IgG1 subclass being the most abundant. IgG1 is composed of two Fab regions connected to a Fc region through a 15-residue hinge peptide. Two glycan chains are conserved in the Fc region in IgG; however, their importance for the structure of intact IgG1 has remained unclear. Read More

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Anisotropic ferroelectric distortion effects on the RKKY interaction in topological crystalline insulators.

Sci Rep 2021 Mar 5;11(1):5273. Epub 2021 Mar 5.

Department of Energy Engineering and Physics, Amirkabir University of Technology, 14588, Tehran, Iran.

Manipulation of electronic and magnetic properties of topological materials is a topic of much interest in spintronic and valleytronic applications. Perturbation tuning of multiple Dirac cones on the (001) surface of topological crystalline insulators (TCIs) is also a related topic of growing interest. Here we show the numerical evidence for the ferroelectric structural distortion effects on the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction between two magnetic impurity moments on the SnTe (001) and related alloys. Read More

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Metabolic signatures of osteoarthritis in urine using liquid chromatography-high resolution tandem mass spectrometry.

Metabolomics 2021 03 3;17(3):29. Epub 2021 Mar 3.

Centre for Analytical Bioscience, Advanced Materials and Healthcare Technologies Division, School of Pharmacy, University of Nottingham, Nottingham, NG7 2RD, UK.

Introduction: Osteoarthritis (OA) is a common cause of disability in older people, but its aetiology is not yet fully understood. Biomarkers of OA from metabolomics studies have shown potential use in understanding the progression and pathophysiology of OA.

Objectives: To investigate possible surrogate biomarkers of knee OA in urine using metabolomics to contribute towards a better understanding of OA progression and possible targeted treatment. Read More

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Quantized Interval Type-2 Fuzzy Control for Persistent Dwell-Time Switched Nonlinear Systems With Singular Perturbations.

IEEE Trans Cybern 2021 Feb 10;PP. Epub 2021 Feb 10.

This article investigates the problem of quantized fuzzy control for discrete-time switched nonlinear singularly perturbed systems, where the singularly perturbed parameter (SPP) is employed to represent the degree of separation between the fast and slow states. Taking a full account of features in such switched nonlinear systems, the persistent dwell-time switching rule, the technique of singular perturbation and the interval type-2 Takagi-Sugeno fuzzy model are introduced. Then, by means of constructing SPP-dependent multiple Lyapunov-like functions, some sufficient conditions with the ability to ensure the stability and an expected H∞ performance of the closed-loop system are deduced. Read More

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February 2021

Urinary Metabolomic Profiling Reveals Biological Pathways and Predictive Signatures Associated with Childhood Asthma.

J Asthma Allergy 2020 18;13:713-724. Epub 2020 Dec 18.

Department of Pulmonology, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, Zhejiang 310052, China.

Background: Despite considerable efforts, the pathogenic mechanisms of asthma are still incompletely understood, due to its heterogeneous nature. However, metabolomics can offer a global view of a biological system, making it a valuable tool for further elucidation of mechanisms and biomarker discovery in asthma.

Methods: GC-MS-based metabolomic analysis was conducted for comparison of urine metabolic profiles between asthmatic children (n=30) and healthy controls (n=30). Read More

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December 2020

New Invariant Expressions in Chemical Kinetics.

Entropy (Basel) 2020 Mar 24;22(3). Epub 2020 Mar 24.

Department of Electronics and Information Systems ELIS, Ghent University, Building S-8, Krijgslaan 281, B-9000 Ghent, Belgium.

This paper presents a review of our original results obtained during the last decade. These results have been found theoretically for classical mass-action-law models of chemical kinetics and justified experimentally. In contrast with the traditional invariances, they relate to a special battery of kinetic experiments, not a single experiment. Read More

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Thermodynamic Assessment of the Partitioning of Acetone between Supercritical CO and Polystyrene Using the Polar PC-SAFT Equation of State.

ACS Omega 2020 Nov 3;5(45):29530-29537. Epub 2020 Nov 3.

ENNOVA LLC, Stafford, Texas 77477, United States.

Supercritical carbon dioxide (scCO) has gained considerable attention in the process industry due to its favorable economic, environmental, and technical characteristics. Polymer processing is one of the key industrial applications where scCO plays an important role. In order to be able to efficiently design the polymer processing equipment, understanding the phase behavior and partition of solutes between scCO and polymers is necessary. Read More

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November 2020

BMP signaling plays a role in anterior-neural/head development, but not organizer activity, in the gastropod Crepidula fornicata.

Dev Biol 2020 07 7;463(2):135-157. Epub 2020 May 7.

University of Illinois, Department of Cell & Developmental Biology, 601 S. Goodwin Ave., Urbana, IL, 61801, USA. Electronic address:

BMP signaling is involved in many aspects of metazoan development, with two of the most conserved functions being to pattern the dorsal-ventral axis and to specify neural versus epidermal fates. An active area of research within developmental biology asks how BMP signaling was modified over evolution to build disparate body plans. Animals belonging to the superclade Spiralia/Lophotrochozoa are excellent experimental subjects for studying the evolution of BMP signaling because a highly conserved, stereotyped early cleavage program precedes the emergence of distinct body plans. Read More

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Comprehensive analysis of effective reflection distance and its association with wave reflection strength under diverse hemodynamic conditions in anesthetized dogs.

J Biomech 2020 05 17;104:109753. Epub 2020 Mar 17.

Department of Cardiovascular Dynamics, National Cerebral and Cardiovascular Center, Suita 564-8565, Japan.

Pressure wave reflection is associated with cardiovascular risk. The conceptual distance to a theoretical major reflection site, termed effective reflection distance (ERD), has been associated with aging and augmentation index (AIx) clinically. However, it remains unclear whether and how ERD varies and associates with AIx when the hemodynamic condition is acutely perturbed in a patient. Read More

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Field-enhanced selectivity in nanoconfined ionic transport.

Ke Zhou Zhiping Xu

Nanoscale 2020 Mar;12(11):6512-6521

Applied Mechanics Laboratory, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China.

Fluid transport confined in nanochannels shows ultrafast permeation and highly efficient separation performance. However, the size-controlled selectivity of hydrated ions with a similar valence and size, such as alkali ions, is well below 5. We propose in this work to boost ion selectivity through the interaction with the wall of flow channels, which can be enhanced by applying an external electric field across the channel. Read More

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Great Impostors: Extremely Compact, Merging Binary Neutron Stars in the Mass Gap Posing as Binary Black Holes.

Phys Rev Lett 2020 Feb;124(7):071101

Department of Physics, University of the Ryukyus, Senbaru, Nishihara, Okinawa 903-0213, Japan.

Can one distinguish a binary black hole undergoing a merger from a binary neutron star if the individual compact companions have masses that fall inside the so-called mass gap of 3-5  M_{⊙}? For neutron stars, achieving such masses typically requires extreme compactness and in this work we present initial data and evolutions of binary neutron stars initially in quasiequilibrium circular orbits having a compactness C=0.336. These are the most compact, nonvacuum, quasiequilibrium binary objects that have been constructed and evolved to date, including boson stars. Read More

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February 2020

Phase behavior of pharmaceutically relevant polymer/solvent mixtures.

Int J Pharm 2020 Mar 24;577:119065. Epub 2020 Jan 24.

Department of Biochemical and Chemical Engineering, Laboratory of Thermodynamics, TU Dortmund University, Emil-Figge-Str. 70, D-44227 Dortmund, Germany. Electronic address:

In the pharmaceutical industry, polymers are used as excipients for formulating poorly water-soluble active pharmaceutical ingredients (APIs) in so-called "amorphous solid dispersions" (ASDs). ASDs can be produced via solvent-based processes, where API and polymer are both dissolved in a solvent, followed by a solvent evaporation step (e.g. Read More

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Axo-glial interdependence in peripheral nerve development.

Development 2019 11 12;146(21). Epub 2019 Nov 12.

Department of Neurogenetics, Max Planck Institute of Experimental Medicine, 37075 Göttingen, Germany

During the development of the peripheral nervous system, axons and myelinating Schwann cells form a unique symbiotic unit, which is realized by a finely tuned network of molecular signals and reciprocal interactions. The importance of this complex interplay becomes evident after injury or in diseases in which aspects of axo-glial interaction are perturbed. This Review focuses on the specific interdependence of axons and Schwann cells in peripheral nerve development that enables axonal outgrowth, Schwann cell lineage progression, radial sorting and, finally, formation and maintenance of the myelin sheath. Read More

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November 2019

n-Butylparaben exposure through gestation and lactation impairs spermatogenesis and steroidogenesis causing reduced fertility in the F1 generation male rats.

Environ Pollut 2020 Jan 16;256:112957. Epub 2019 Aug 16.

National Centre for Preclinical Reproductive and Genetic Toxicology, ICMR-National Institute for Research in Reproductive Health, Parel, Mumbai, Maharashtra, India. Electronic address:

Parabens are class of preservatives used in vast majority of commercial products, and a potential Endocrine Disrupting Chemical (EDC). The present study was undertaken to delineate the effects of n-butylparaben on F1 male progeny exposed maternally through gestation and lactation via subcutaneous route. The F0 dams were given subcutaneous injections of n-butylparaben from gestation day (GD) 6 to postnatal day (PND) 21 with doses of 10, 100, 1000 mg/kg Bw/day in corn oil. Read More

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January 2020

Nucleolus: A Protein Quality Control Compartment.

Trends Biochem Sci 2019 12 23;44(12):993-995. Epub 2019 Oct 23.

Centre for Brain Research, Indian Institute of Science, Bangalore 560012, India. Electronic address:

Frottin et al. uncovered a role for the nucleolus as a key quality control compartment that regulates misfolded nuclear proteins. This nonmembrane compartment achieves this by forming liquid-like protein condensates that aid protein refolding in a heat-shock protein (Hsp)70-dependent manner. Read More

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December 2019

Signal-switchable lab-on-paper photoelectrochemical aptasensing system integrated triple-helix molecular switch with charge separation and recombination regime of type-II CdTe@CdSe core-shell quantum dots.

Biosens Bioelectron 2020 Jan 15;147:111786. Epub 2019 Oct 15.

School of Chemistry and Chemical Engineering, University of Jinan, Jinan, 250022, PR China.

Herein, a new "on-off-on" signal switch system combined triple helix molecular switch with efficient charge separation and transfer between different sensitization units was designed for the ultrasensitive photoelectrochemical (PEC) determination of prostate-specific antigen (PSA). Concretely, the initial "signal-on" state was obtained via the cascaded sensitization structure consisting of type-II CdTe@CdSe core-shell quantum dots (QDs), CdS QDs, and ZnO nanotubes, which were assembled on Au nanoparticles modified paper fibers with the aid of signal transduction probe (STP). Thereinto, the type-II CdTe@CdSe QDs with hole-localizing core and electron-localizing shell could enable the ultrafast charge transfer and retard the charge recombination, magnifying the initial photocurrent response and preserving the high efficiency of signal-switchable PEC aptasensing system. Read More

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January 2020

An SDS-PAGE based proteomic approach for N-terminome profiling.

Analyst 2019 Nov;144(23):7001-7009

Center for Theragnosis, Korea Institute of Science and Technology, Seoul 02792, Korea.

Initial sample quantity, solubilization, separation, and visualization of proteins or their proteolytically altered products are some of the challenges of the currently available solution-based N-termini enrichment methods. We therefore took advantage of the conventional SDS-PAGE system and attempted to address these challenges by proposing a simple yet reproducible, negative selection N-termini enrichment strategy coupled with mass spectrometry based protein identification. It includes in-gel protein level labeling of primary amines using d6-acetic anhydride and post-digestion negative selection of labeled N-terminal peptide(s) using N-hydroxysuccinimide activated agarose beads. Read More

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November 2019

Direct numerical simulation of vortex-induced instability for a zero-pressure-gradient boundary layer.

Phys Rev E 2019 Sep;100(3-1):033118

High Performance Computing Laboratory, Indian Institute of Technology Kanpur, Kanpur-208 016, India.

Vortex-induced instability caused by a free-stream vortical excitation is explored here quantitatively with the help of controlled computational results. First, the computed results are compared with experimental results in Lim et al. [Exp. Read More

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September 2019

Stress granule mediated protein aggregation and underlying gene defects in the FTD-ALS spectrum.

Neurobiol Dis 2020 02 15;134:104639. Epub 2019 Oct 15.

Neurodegenerative Brain Diseases group, Center for Molecular Neurology, VIB, Antwerp, Belgium; Laboratory of Neurogenetics, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium. Electronic address:

Stress granules (SGs) are dynamic membraneless compartments composed out of RNA-binding proteins (RBPs) and RNA molecules that assemble temporarily to allow the cell to cope with cellular stress by stalling mRNA translation and moving synthesis towards cytoprotective proteins. Aberrant SGs have become prime suspects in the nucleation of toxic protein aggregation in frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Perturbed SG dynamics appears to be mediated by alterations in RNA binding proteins (RBP). Read More

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February 2020

Coordinate-independent singular perturbation reduction for systems with three time scales.

Math Biosci Eng 2019 06;16(5):5062-5091

Mathematik A, RWTH Aachen, 52056 Aachen, Germany.

On the basis of recent work by Cardin and Teixeira on ordinary differential equations with more than two time scales, we devise a coordinate-independent reduction for systems with three time scales; thus no a priori separation of variables into fast, slow etc. is required. Moreover we consider arbitrary parameter dependent systems and extend earlier work on Tikhonov-Fenichel parameter values - i. Read More

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Rotational Spectrum, Tunneling Motions, and Intramolecular Potential Barriers in Benzyl Mercaptan.

J Phys Chem A 2019 Oct 18;123(39):8435-8440. Epub 2019 Sep 18.

Departamento de Química Física y Química Inorgánica - IU CINQUIMA, Facultad de Ciencias , Universidad de Valladolid , Paseo de Belén, 7 , E-47011 , Valladolid , Spain.

The rotational spectrum of benzyl mercaptan (parent and four isotopologues) has been assigned in a supersonic jet expansion using chirped-pulse Fourier transform microwave spectroscopy. The spectrum is characterized by torsional tunneling doublings, strongly perturbed by Coriolis interactions. The experimental rotational constants reveal that the sulfur atom is located above the ring plane in a conformation. Read More

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October 2019

Glucocorticoid receptor signaling in leukocytes after early life adversity.

Dev Psychopathol 2020 08;32(3):853-863

Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, L-4354, Grand-Duchy of Luxembourg.

Early life adversity (ELA) has been associated with inflammation and immunosenescence, as well as hyporeactivity of the HPA axis. Because the immune system and the HPA axis are tightly intertwined around the glucocorticoid receptor (GR), we examined peripheral GR functionality in the EpiPath cohort among participants who either had been exposed to ELA (separation from parents and/or institutionalization followed by adoption; n = 40) or had been reared by their biological parents (n = 72).Expression of the strict GR target genes FKBP5 and GILZ as well as total and 1F and 1H GR transcripts were similar between groups. Read More

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Metabolic Profiling Reveals Biochemical Pathways and Potential Biomarkers of Spinocerebellar Ataxia 3.

Front Mol Neurosci 2019 27;12:159. Epub 2019 Jun 27.

Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou, China.

Spinocerebellar ataxia 3, also known as Machado-Joseph disease (SCA3/MJD), is a rare autosomal-dominant neurodegenerative disease caused by an abnormal expansion of CAG repeats in the gene. In the present study, we performed a global metabolomic analysis to identify pathogenic biochemical pathways and novel biomarkers implicated in SCA3 patients. Metabolic profiling of serum samples from 13 preclinical SCA3 patients, 13 symptomatic SCA3 patients, and 15 healthy controls were mapped using ultra-high-performance liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry techniques. Read More

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Effect of dehydrocholic acid conjugated with a hydrocarbon on a lipid bilayer composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine.

Colloids Surf B Biointerfaces 2019 Sep 10;181:58-65. Epub 2019 May 10.

Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka, 560-8531, Japan.

The effects of bile acids, dehydrocholic acid (DHA) and DHA conjugated with a hydrocarbon (6-aminohexanoate; 6A-DHA) were evaluated using a lipid bilayer composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC). DOPC formed a homogenous thin membrane in presence or absence of the DHA, while 20 mol% 6A-DHA induced phase separation on the DOPC thin membrane. It was observed formation of a stomatocyte-like liposomes when these membranes were suspended in a basic solvent. Read More

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September 2019

Targeted metabolomic profiling of low and high grade serous epithelial ovarian cancer tissues: a pilot study.

Metabolomics 2018 11 24;14(12):154. Epub 2018 Nov 24.

Department of Obstetrics and Gynecology, William Beaumont Health, Royal Oak, MI, USA.

Introduction: Epithelial ovarian cancer (EOC) remains the leading cause of death from gynecologic malignancies and has an alarming global fatality rate. Besides the differences in underlying pathogenesis, distinguishing between high grade (HG) and low grade (LG) EOC is imperative for the prediction of disease progression and responsiveness to chemotherapy.

Objectives: The aim of this study was to investigate, the tissue metabolome associated with HG and LG serous epithelial ovarian cancer. Read More

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November 2018

Metabolomic identification of diagnostic serum-based biomarkers for advanced stage melanoma.

Metabolomics 2018 08 3;14(8):105. Epub 2018 Aug 3.

Department of General Surgery, Beaumont Health, Royal Oak, MI, USA.

Introduction: Melanoma is a highly aggressive malignancy and is currently one of the fastest growing cancers worldwide. While early stage (I and II) disease is highly curable with excellent prognosis, mortality rates rise dramatically after distant spread. We sought to identify differences in the metabolome of melanoma patients to further elucidate the pathophysiology of melanoma and identify potential biomarkers to aid in earlier detection of recurrence. Read More

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H NMR based serum metabolic profiling reveals differentiating biomarkers in patients with diabetes and diabetes-related complication.

Diabetes Metab Syndr 2019 Jan - Feb;13(1):290-298. Epub 2018 Sep 12.

Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, Lucknow, India; Department of Biotechnology, Mahatma Gandhi Central University, Motihari, India. Electronic address:

Background: Diabetes is among the most prevalent diseases worldwide, of all the affected individuals a significant proportion of the population remains undiagnosed due to lack of specific symptoms early in this disorder and inadequate diagnostics. Diabetes and its associated sequela, i.e. Read More

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Quantifying Dynamic Balance in Young, Elderly and Parkinson's Individuals: A Systematic Review.

Front Aging Neurosci 2018 22;10:387. Epub 2018 Nov 22.

School of Human Kinetics, University of Ottawa, Ottawa, ON, Canada.

Falling is one of the primary concerns for people with Parkinson's Disease and occurs predominately during dynamic movements, such as walking. Several methods have been proposed to quantify dynamic balance and to assess fall risk. However, no consensus has been reached concerning which method is most appropriate for examining walking balance during unperturbed and perturbed conditions, particularly in Parkinson's Disease individuals. Read More

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November 2018

A Systems-Level Study Reveals Regulators of Membrane-less Organelles in Human Cells.

Mol Cell 2018 12 29;72(6):1035-1049.e5. Epub 2018 Nov 29.

Institute of Molecular Life Sciences, University of Zurich, 8057 Zurich, Switzerland. Electronic address:

Membrane-less organelles (MLOs) are liquid-like subcellular compartments that form through phase separation of proteins and RNA. While their biophysical properties are increasingly understood, their regulation and the consequences of perturbed MLO states for cell physiology are less clear. To study the regulatory networks, we targeted 1,354 human genes and screened for morphological changes of nucleoli, Cajal bodies, splicing speckles, PML nuclear bodies (PML-NBs), cytoplasmic processing bodies, and stress granules. Read More

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December 2018

Advances and challenges in understanding the role of the lipid raft proteome in human health.

Expert Rev Proteomics 2018 12 13;15(12):1053-1063. Epub 2018 Nov 13.

a Precision & Systems Biomedicine Laboratory , QIMR Berghofer Medical Research Institute , Brisbane , Australia.

Introduction: Phase separation as a biophysical principle drives the formation of liquid-ordered 'lipid raft' membrane microdomains in cellular membranes, including organelles. Given the critical role of cellular membranes in both compartmentalization and signaling, clarifying the roles of membrane microdomains and their mutual regulation of/by membrane proteins is important in understanding the fundamentals of biology, and has implications for health. Areas covered: This article will consider the evidence for lateral membrane phase separation in model membranes and organellar membranes, critically evaluate the current methods for lipid raft proteomics and discuss the biomedical implications of lipid rafts. Read More

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December 2018