17 results match your criteria peg-hccs

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Antioxidant Carbon Nanoparticles Inhibit Fibroblast-Like Synoviocyte Invasiveness and Reduce Disease Severity in a Rat Model of Rheumatoid Arthritis.

Antioxidants (Basel) 2020 Oct 16;9(10). Epub 2020 Oct 16.

Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA.

Reactive oxygen species have been involved in the pathogenesis of rheumatoid arthritis (RA). Our goal was to determine the effects of selectively scavenging superoxide (O) and hydroxyl radicals with antioxidant nanoparticles, called poly(ethylene glycol)-functionalized hydrophilic carbon clusters (PEG-HCCs), on the pathogenic functions of fibroblast-like synoviocytes (FLS) from patients with rheumatoid arthritis (RA) and on the progression of an animal model of RA. We used human FLS from patients with RA to determine PEG-HCC internalization and effects on FLS cytotoxicity, invasiveness, proliferation, and production of proteases. Read More

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October 2020

Use of a bioengineered antioxidant in mouse models of metabolic syndrome.

Expert Opin Investig Drugs 2020 Feb 20;29(2):209-219. Epub 2020 Jan 20.

Interdepartmental Program in Translation Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, USA.

: Oxidative stress has been implicated in metabolic syndrome (MetS); however, antioxidants such as vitamin E have had limited success in the clinic. This prompts the question of what effects amore potent antioxidant might produce. A prime candidate is the recently developed bioengineered antioxidant, poly(ethylene glycol)-functionalizedhydrophilic carbon clusters (PEG-HCCs), which are capable of neutralizing the reactive oxygen species (ROS) superoxide anion and hydroxyl radical at10/molecule of PEG-HCC. Read More

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February 2020

Critical Comparison of the Superoxide Dismutase-like Activity of Carbon Antioxidant Nanozymes by Direct Superoxide Consumption Kinetic Measurements.

ACS Nano 2019 10 17;13(10):11203-11213. Epub 2019 Sep 17.

Division of Hematology, Department of Internal Medicine , University of Texas-McGovern Medical School , 6431 Fannin Street , Houston , Texas 77030 , United States.

The superoxide dismutase-like activity of poly(ethylene glycolated) hydrophilic carbon clusters (PEG-HCCs), anthracite and bituminous graphene quantum dots (PEG-aGQDs and PEG-bGQDs, respectively), and two fullerene carbon nanozymes, tris malonyl-C fullerene (C3) and polyhydroxylated-C fullerene (C-OH), were compared using direct optical stopped-flow kinetic measurements, together with three native superoxide dismutases (SODs), CuZnSOD, MnSOD, and FeSOD, at both pH 12.7 and 8.5. Read More

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October 2019

Catalytic oxidation and reduction reactions of hydrophilic carbon clusters with NADH and cytochrome C: features of an electron transport nanozyme.

Nanoscale 2019 Jun;11(22):10791-10807

Texas A&M Health Science Center Institute of Biosciences and Technology, Houston, Texas 77030, USA.

Previously, our group reported on the promising efficacy of poly(ethylene glycol)-hydrophilic carbon clusters (PEG-HCCs) to work as broadly active and high capacity antioxidants in brain ischemia and injury models including stroke and traumatic brain injury coupled with hemorrhagic shock. PEG-HCCs are a carbon nanomaterial derived from harsh oxidation of single wall carbon nanotubes and covalently modified with poly(ethylene glycol). They retain no tubular remnants and are composed of a highly oxidized carbon core functionalized with epoxy, peroxyl, quinone, ketone, carboxylate, and hydroxyl groups. Read More

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Functional and Structural Improvement with a Catalytic Carbon Nano-Antioxidant in Experimental Traumatic Brain Injury Complicated by Hypotension and Resuscitation.

J Neurotrauma 2019 07 13;36(13):2139-2146. Epub 2019 Mar 13.

2 Department of Chemistry, Rice University, Houston, Texas.

Hypotension worsens outcome after all severities of traumatic brain injury (TBI), with loss of cerebral autoregulation being a potential contributor. Previously, we demonstrated that intravenous injection of a high capacity catalytic antioxidant, poly(ethylene)glycol conjugated hydrophilic carbon clusters (PEG-HCCs) rapidly restored cerebral perfusion and acutely restored brain oxidative balance in a TBI model complicated by hemorrhagic hypotension without evidence of toxicity. Here, we tested whether these acute effects translated into behavioral and structural benefit. Read More

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Efficacy of Novel Carbon Nanoparticle Antioxidant Therapy in a Severe Model of Reversible Middle Cerebral Artery Stroke in Acutely Hyperglycemic Rats.

Front Neurol 2018 9;9:199. Epub 2018 Apr 9.

Department of Neurology and Center for Translational Research on Inflammatory Diseases, Baylor College of Medicine, Michael E. DeBakey VA Medical Center, Houston, TX, United States.

Introduction: While oxidative stress can be measured during transient cerebral ischemia, antioxidant therapies for ischemic stroke have been clinically unsuccessful. Many antioxidants are limited in their range and/or capacity for quenching radicals and can generate toxic intermediates overwhelming depleted endogenous protection. We developed a new antioxidant class, 40 nm × 2 nm carbon nanoparticles, hydrophilic carbon clusters, conjugated to poly(ethylene glycol) termed PEG-HCCs. Read More

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Transfer of Dyes and Drugs into Cells Using EGFR-Targeted Nanosyringes.

ACS Chem Neurosci 2018 01 14;9(1):107-117. Epub 2017 Aug 14.

Kenneth R. Peak Brain and Pituitary Tumor Center, Department of Neurosurgery, Houston Methodist Hospital , Houston, Texas 77030, United States.

Selective targeting of drug loaded nanovectors to specific epitopes highly expressed on the surface of cancer cells is a goal for nanotechnologists. We have modified our previously described PEGylated-hydrophilic carbon clusters (PEG-HCCs) so that the epidermal growth factor receptor (EGFR) binding peptide, GE11, is attached using click chemistry at the end of each PEG. The resulting nanosyringe, Pep-PEG-HCC, can be loaded with a wide range of hydrophobic drugs and dyes. Read More

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January 2018

Perylene Diimide as a Precise Graphene-like Superoxide Dismutase Mimetic.

ACS Nano 2017 02 31;11(2):2024-2032. Epub 2017 Jan 31.

Hematology, Internal Medicine, University of Texas Houston Medical School , Houston, Texas 77030, United States.

Here we show that the active portion of a graphitic nanoparticle can be mimicked by a perylene diimide (PDI) to explain the otherwise elusive biological and electrocatalytic activity of the nanoparticle construct. Development of molecular analogues that mimic the antioxidant properties of oxidized graphenes, in this case the poly(ethylene glycolated) hydrophilic carbon clusters (PEG-HCCs), will afford important insights into the highly efficient activity of PEG-HCCs and their graphitic analogues. PEGylated perylene diimides (PEG-PDI) serve as well-defined molecular analogues of PEG-HCCs and oxidized graphenes in general, and their antioxidant and superoxide dismutase-like (SOD-like) properties were studied. Read More

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February 2017

Preferential uptake of antioxidant carbon nanoparticles by T lymphocytes for immunomodulation.

Sci Rep 2016 Sep 22;6:33808. Epub 2016 Sep 22.

Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, Texas 77030, USA.

Autoimmune diseases mediated by a type of white blood cell-T lymphocytes-are currently treated using mainly broad-spectrum immunosuppressants that can lead to adverse side effects. Antioxidants represent an alternative approach for therapy of autoimmune disorders; however, dietary antioxidants are insufficient to play this role. Antioxidant carbon nanoparticles scavenge reactive oxygen species (ROS) with higher efficacy than dietary and endogenous antioxidants. Read More

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September 2016

Characterization of a novel MR-detectable nanoantioxidant that mitigates the recall immune response.

NMR Biomed 2016 10 24;29(10):1436-44. Epub 2016 Aug 24.

Department of Molecular Physiology & Biophysics, Baylor College of Medicine, Houston, TX, USA.

In many human diseases, the presence of inflammation is associated with an increase in the level of reactive oxygen species (ROS). The resulting state of oxidative stress is highly detrimental and can initiate a cascade of events that ultimately lead to cell death. Thus, many therapeutic attempts have been focused on either modulating the immune system to lower inflammation or reducing the damaging caused by ROS. Read More

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October 2016

Mechanistic Study of the Conversion of Superoxide to Oxygen and Hydrogen Peroxide in Carbon Nanoparticles.

ACS Appl Mater Interfaces 2016 Jun 10;8(24):15086-92. Epub 2016 Jun 10.

Hematology, Department of Internal Medicine, University of Texas Houston Medical School , Houston, Texas 77030, United States.

Hydrophilic carbon clusters (HCCs) are oxidized carbon nanoparticles with a high affinity for electrons. The electron accepting strength of HCCs, employing the efficient conversion of superoxide (O2(•-)) to molecular oxygen (O2) via single-electron oxidation, was monitored using cyclic voltammetry and electron paramagnetic resonance spectroscopy. We found that HCCs possess O2 reduction reaction (ORR) capabilities through a two-electron process with the formation of H2O2. Read More

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Highly efficient conversion of superoxide to oxygen using hydrophilic carbon clusters.

Proc Natl Acad Sci U S A 2015 Feb 9;112(8):2343-8. Epub 2015 Feb 9.

Department of Chemistry and Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, TX 77005;

Many diseases are associated with oxidative stress, which occurs when the production of reactive oxygen species (ROS) overwhelms the scavenging ability of an organism. Here, we evaluated the carbon nanoparticle antioxidant properties of poly(ethylene glycolated) hydrophilic carbon clusters (PEG-HCCs) by electron paramagnetic resonance (EPR) spectroscopy, oxygen electrode, and spectrophotometric assays. These carbon nanoparticles have 1 equivalent of stable radical and showed superoxide (O2 (•-)) dismutase-like properties yet were inert to nitric oxide (NO(•)) as well as peroxynitrite (ONOO(-)). Read More

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February 2015

Hydrophilic carbon clusters as therapeutic, high-capacity antioxidants.

Trends Biotechnol 2014 Oct 28;32(10):501-5. Epub 2014 Aug 28.

Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Department of Neurology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA; Center for Translational Research in Inflammatory Diseases, Michael E. DeBakey VA Medical Center, 2002 Holcombe Boulevard, Houston, TX 77030, USA; Neurology Care Line, Michael E. DeBakey VA Medical Center, 2002 Holcombe Boulevard, Houston, TX 77030, USA. Electronic address:

Oxidative stress reflects an excessive accumulation of reactive oxygen species (ROS) and is a hallmark of several acute and chronic human pathologies. Although many antioxidants have been investigated, most have demonstrated poor efficacy in clinical trials. Here we discuss the limitations of current antioxidants and describe a new class of nanoparticle antioxidants, poly(ethylene glycol)-functionalized hydrophilic carbon clusters (PEG-HCCs). Read More

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October 2014

Design of poly(ethylene glycol)-functionalized hydrophilic carbon clusters for targeted therapy of cerebrovascular dysfunction in mild traumatic brain injury.

J Neurotrauma 2013 May 5;30(9):789-96. Epub 2012 Nov 5.

Department of Chemistry, Rice University, Houston, Texas 77005, USA.

Traumatic brain injury (TBI) involves the elaboration of oxidative stress that causes cerebrovascular dysfunction, including impairment of autoregulation of cerebral blood flow. Currently, there is no clinically effective antioxidant treatment for these pathologies. Most currently available antioxidants act through mechanisms in which the antioxidant either transfers the radical or requires regeneration, both of which are impaired in the toxic post-TBI environment. Read More

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Antioxidant carbon particles improve cerebrovascular dysfunction following traumatic brain injury.

ACS Nano 2012 Sep 15;6(9):8007-14. Epub 2012 Aug 15.

Interdepartmental Program in Translational Biology and Molecular Medicine and Department of Molecular Physiology and Biophysics, Baylor College of Medicine, One Baylor Plaza, Houston, Texas 77030, United States.

Injury to the neurovasculature is a feature of brain injury and must be addressed to maximize opportunity for improvement. Cerebrovascular dysfunction, manifested by reduction in cerebral blood flow (CBF), is a key factor that worsens outcome after traumatic brain injury (TBI), most notably under conditions of hypotension. We report here that a new class of antioxidants, poly(ethylene glycol)-functionalized hydrophilic carbon clusters (PEG-HCCs), which are nontoxic carbon particles, rapidly restore CBF in a mild TBI/hypotension/resuscitation rat model when administered during resuscitation--a clinically relevant time point. Read More

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September 2012

Antibody-targeted nanovectors for the treatment of brain cancers.

ACS Nano 2012 Apr 13;6(4):3114-20. Epub 2012 Mar 13.

Department of Neurosurgery, Methodist Hospital, 6560 Fannin Street, Houston, Texas 77030, United States.

Introduced here is the hydrophilic carbon clusters (HCCs) antibody drug enhancement system (HADES), a methodology for cell-specific drug delivery. Antigen-targeted, drug-delivering nanovectors are manufactured by combining specific antibodies with drug-loaded poly(ethylene glycol)-HCCs (PEG-HCCs). We show that HADES is highly modular, as both the drug and antibody component can be varied for selective killing of a range of cultured human primary glioblastoma multiforme. Read More

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Effective drug delivery, in vitro and in vivo, by carbon-based nanovectors noncovalently loaded with unmodified Paclitaxel.

ACS Nano 2010 Aug;4(8):4621-36

Department of Chemistry, Rice University, MS-222, 6100 Main Street, Houston, Texas 77005, USA.

Many new drugs have low aqueous solubility and high therapeutic efficacy. Paclitaxel (PTX) is a classic example of this type of compound. Here we show that extremely small (<40 nm) hydrophilic carbon clusters (HCCs) that are PEGylated (PEG-HCCs) are effective drug delivery vehicles when simply mixed with paclitaxel. Read More

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