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1.
Small ; 20(27): e2312211, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38381004

ABSTRACT

Uveal melanoma (UM) is an ocular cancer predominantly affecting adults, characterized by challenging diagnostic outcomes. This research endeavors to develop an innovative multifunctional nanocomposite system sensitive to near-infrared (NIR) radiation, serving as both a non-oxygen free-radical generator and a photothermal agent. The designed system combines azobis isobutyl imidazoline hydrochloride (AIBI) with mesoporous copper sulfide (MCuS) nanoparticles. MCuS harnesses NIR laser energy to induce photothermal therapy, converting light energy into heat to destroy cancer cells. Simultaneously, AIBI is activated by the NIR laser to produce alkyl radicals, which induce DNA damage in remaining cancer cells. This distinctive feature equips the designed system to selectively eliminate cancers in the hypoxic tumor microenvironment. MCuS is also beneficial to scavenge the overexpressed glutathione (GSH) in the tumor microenvironment. GSH generally consumes free radicals and hiders the PDT effect. To enhance control over AIBI release in cancer cells, 1-tetradecyl alcohol (TD), a phase-changing material, is introduced onto the surface of MCuS nanoparticles to create the final AMPT nanoparticle system. In vitro and in vivo experiments confirm the remarkable anti-tumor efficacy of AMPT. Notably, the study introduces an orthotopic tumor model for UM, demonstrating the feasibility of precise and effective targeted treatment within the ocular system.


Subject(s)
Copper , Melanoma , Nanocomposites , Photothermal Therapy , Uveal Neoplasms , Copper/chemistry , Uveal Neoplasms/therapy , Uveal Neoplasms/pathology , Melanoma/therapy , Melanoma/pathology , Nanocomposites/chemistry , Nanocomposites/therapeutic use , Humans , Animals , Free Radicals/chemistry , Cell Line, Tumor , Porosity , Sulfides/chemistry , Mice , Imidazoles/chemistry , Tumor Microenvironment/drug effects , Glutathione/metabolism , Glutathione/chemistry
2.
Macromol Rapid Commun ; 44(20): e2300298, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37548089

ABSTRACT

This work introduces a novel multifunctional system called UPIPF (upconversion-polydopamine-indocyanine-polyethylene-folic) for upconversion luminescent (UCL) imaging of cancer cells using near-infrared (NIR) illumination. The system demonstrates efficient inhibition of human hepatoma (HepG2) cancer cells through a combination of NIR-triggered photodynamic therapy (PDT) and enhanced photothermal therapy (PTT). Initially, upconversion nanoparticles (UCNP) are synthesized using a simple thermal decomposition method. To improve their biocompatibility and aqueous dispersibility, polydopamine (PDA) is introduced to the UCNP via a ligand exchange technique. Indocyanine green (ICG) molecules are electrostatically attached to the surface of the UCNP-polydopamine (UCNP@PDAs) complex to enhance the PDT and PTT effects. Moreover, polyethylene glycol (PEG)-modified folic acid (FA) is incorporated into the UCNP-polydopamine-indocyanine-green (UCNP@PDA-ICGs) nanoparticles to enhance their targeting capability against cancer cells. The excellent UCL properties of these UCNP enable the final UCNP@PDA-ICG-PEG-FA nanoparticles (referred to as UPIPF) to serve as a potential candidate for efficient anticancer drug delivery, real-time imaging, and early diagnosis of cancer cells. Furthermore, the UPIPF system exhibits PDT-assisted PTT effects, providing a convenient approach for efficient cancer cell inhibition (more than 99% of cells are killed). The prepared UPIPF system shows promise for early diagnosis and simultaneous treatment of malignant cancers.


Subject(s)
Nanoparticles , Neoplasms , Photochemotherapy , Humans , Indocyanine Green/pharmacology , Indocyanine Green/therapeutic use , Indoles/pharmacology , Polymers/pharmacology , Polyethylene Glycols , Photochemotherapy/methods , Cell Line, Tumor , Neoplasms/diagnostic imaging , Neoplasms/drug therapy
3.
Small ; 16(43): e2004161, 2020 10.
Article in English | MEDLINE | ID: mdl-33000898

ABSTRACT

This article reports the fabrication of a smart biomimetic enzyme system, which incorporates a pH-responsive chemodynamic therapy (CDT) combined with a photothermal (PTT) therapy approach in resolving the high recurrence rate of deadly cancers. The resulting enzyme system comprises copper sulfide (CuS) nanoparticle (NP) cores as Fenton-like catalysts, and a photothermal-active generation 5 poly(amidoamine) (G5) dendrimer as a template for the entrapment of Cu NPs and the compression of glucose oxidase (GOD). GOD is introduced to produce H2 O2 necessary in the sequential Fenton-like reaction, and this generates hydroxyl radicals that kill the cancerous cells. Polyethylene glycol is added to the system to improve biocompatibility. Mechanism study suggests that the constructed CuS/G5-GOD-based system has a better Fenton-like catalytic activity than a Fe3 O4 -GOD-based system. This allows the further inhibition on the residual tumors from recurrence and metastasis through CDT after being treated by PTT. The developed smart nanoscale biomimetic system shows high efficiency for breast cancer suppression from recurrence and metastasis by combining PTT with a pH-responsive CDT. It has the potential to resolve the essential issue of cancer recurrence after its initial clinic treatment.


Subject(s)
Biomimetics , Nanoparticles , Humans , Neoplasm Recurrence, Local , Photothermal Therapy , Polymers
4.
Nat Mater ; 23(5): 581-582, 2024 May.
Article in English | MEDLINE | ID: mdl-38702543
5.
Int J Mol Sci ; 20(18)2019 Sep 10.
Article in English | MEDLINE | ID: mdl-31509978

ABSTRACT

Tumorous metastasis is a difficult challenge to resolve for researchers and for clinicians. Targeted delivery of antitumor drugs towards tumor cells' nuclei can be a practical approach to resolving this issue. This work describes an efficient nuclear-targeting delivery system prepared from trans-activating transcriptional activator (TAT) peptide-functionalized graphene nanocarriers. The TAT peptide, originally observed in a human immunodeficiency virus 1 (HIV-1), was incorporated with graphene via an edge-functionalized ball-milling method developed by the author's research group. High tumor-targeting capability of the resulting nanocarrier was realized by the strong affinity between TAT and the nuclei of cancer cells, along with the enhanced permeability and retention (EPR) effect of two-dimensional graphene nanosheets. Subsequently, a common antitumor drug, mitomycin C (MMC), was covalently linked to the TAT-functionalized graphene (TG) to form a nuclear-targeted nanodrug MMC-TG. The presence of nanomaterials inside the nuclei of ocular choroidal melanoma (OCM-1) cells was shown using transmission electron microscopy (TEM) and confocal laser scanning microscopy. In vitro results from a Transwell co-culture system showed that most of the MMC-TG nanodrugs were delivered in a targeted manner to the tumorous OCM-1 cells, while a very small amount of MMC-TG was delivered in a non-targeted manner to normal human retinal pigment epithelial (ARPE-19) cells. TEM results further confirmed that apoptosis of OCM-1 cells was started from the lysis of nuclear substances, followed by the disappearance of nuclear membrane and cytoplasm. This suggests that the as-synthesized MMC-TG is a promising nuclear-target nanodrugfor resolution of tumorous metastasis issues at the headstream.


Subject(s)
Choroid Neoplasms/drug therapy , Drug Delivery Systems/methods , Graphite/chemistry , Melanoma/drug therapy , Mitomycin/administration & dosage , Peptides/chemistry , Antibiotics, Antineoplastic/administration & dosage , Antibiotics, Antineoplastic/chemistry , Cell Line , Cell Line, Tumor , Cell Nucleus/drug effects , Cell Nucleus/metabolism , Cell Nucleus/ultrastructure , Choroid Neoplasms/metabolism , Choroid Neoplasms/pathology , Drug Carriers/chemistry , Humans , Melanoma/metabolism , Melanoma/pathology , Microscopy, Electron, Transmission , Mitomycin/chemistry , Nanostructures/administration & dosage , Nanostructures/chemistry , Nanostructures/ultrastructure , tat Gene Products, Human Immunodeficiency Virus/chemistry
6.
Int J Mol Sci ; 20(8)2019 Apr 24.
Article in English | MEDLINE | ID: mdl-31022890

ABSTRACT

The regeneration of neurons is an important goal of neuroscience and clinical medicine. The electrical stimulation of cells is a promising technique to meet this goal. However, its efficiency highly depends on the electrochemical properties of the stimulation electrodes used. This work reports on the preparation and use of a highly electroactive and biocompatible nanoelectrode made from a novel polyaniline functionalized graphene composite. This nanocomposite was prepared using a facile and efficient polymerization-enhanced ball-milling method. It was used to stimulate the growth of PC12 cells under various electrical fields. The enhanced growth of axons and improved wound regeneration of PC12 cells were observed after this treatment, suggesting a promising strategy for neuro traumatology.


Subject(s)
Aniline Compounds/chemistry , Cell Proliferation , Electric Stimulation/instrumentation , Graphite/chemistry , Nanocomposites/chemistry , Neurons/cytology , Animals , Microelectrodes , Nerve Regeneration , PC12 Cells , Polymerization , Rats
7.
Sensors (Basel) ; 17(7)2017 Jul 13.
Article in English | MEDLINE | ID: mdl-28703749

ABSTRACT

Various whole cell-based biosensors have been reported in the literature for the last 20 years and these reports have shown great potential for their use in the areas of pollution detection in environmental and in biomedical diagnostics. Unlike other reviews of this growing field, this mini-review argues that: (1) the selection of reporter genes and their regulatory proteins are directly linked to the performance of celllular biosensors; (2) broad enhancements in microelectronics and information technologies have also led to improvements in the performance of these sensors; (3) their future potential is most apparent in their use in the areas of medical diagnostics and in environmental monitoring; and (4) currently the most promising work is focused on the better integration of cellular sensors with nano and micro scaled integrated chips. With better integration it may become practical to see these cells used as (5) real-time portable devices for diagnostics at the bedside and for remote environmental toxin detection and this in situ application will make the technology commonplace and thus as unremarkable as other ubiquitous technologies.


Subject(s)
Biosensing Techniques , Environmental Monitoring , Genes, Reporter , Humans
8.
Neurocrit Care ; 23(2): 145-8, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26195086

ABSTRACT

Part of the responsibility of a professional society is to establish the expectations for appropriate behavior for its members. Some codes are so essential to a society that the code itself becomes the central document defining the organization and its tenets, as we see with the Hippocratic Oath. In that tradition, we have revised the code of professional conduct for the Neurocritical Care Society into its current version, which emphasizes guidelines for personal behavior, relationships with fellow members, relationships with patients, and our interactions with society as a whole. This will be a living document and updated as the needs of our society change in time.Available online: http://www.neurocriticalcare.org/about-us/bylaws-procedures-and-code-professional-conduct (1) Code of professional conduct (this document) (2) Leadership code of conduct (3) Disciplinary policy.


Subject(s)
Codes of Ethics , Critical Care/ethics , Ethics, Medical , Neurology/ethics , Societies, Medical/ethics , Humans
9.
Adv Mater ; : e2405664, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39049808

ABSTRACT

Over the last decade, carbon-based metal-free electrocatalysts (C-MFECs) have become important in electrocatalysis. This field is started thanks to the initial discovery that nitrogen atom doped carbon can function as a metal-free electrode in alkaline fuel cells. A wide variety of metal-free carbon nanomaterials, including 0D carbon dots, 1D carbon nanotubes, 2D graphene, and 3D porous carbons, has demonstrated high electrocatalytic performance across a variety of applications. These include clean energy generation and storage, green chemistry, and environmental remediation. The wide applicability of C-MFECs is facilitated by effective synthetic approaches, e.g., heteroatom doping, and physical/chemical modification. These methods enable the creation of catalysts with electrocatalytic properties useful for sustainable energy transformation and storage (e.g., fuel cells, Zn-air batteries, Li-O2 batteries, dye-sensitized solar cells), green chemical production (e.g., H2O2, NH3, and urea), and environmental remediation (e.g., wastewater treatment, and CO2 conversion). Furthermore, significant advances in the theoretical study of C-MFECs via advanced computational modeling and machine learning techniques have been achieved, revealing the charge transfer mechanism for rational design and development of highly efficient catalysts. This review offers a timely overview of recent progress in the development of C-MFECs, addressing material syntheses, theoretical advances, potential applications, challenges and future directions.

10.
Front Chem ; 10: 942578, 2022.
Article in English | MEDLINE | ID: mdl-36092674

ABSTRACT

Dry eye disease is a common condition that affects the eyes. It is caused by problems with the tear film and the tear dynamics. Dry eye can be caused by an increase in the amount of reactive oxygen species (ROS) in the corneal epithelium. The treatment for dry eye typically focuses on relieving the uncomfortable symptoms by using eye drops such as artificial tears, antibiotics, and by using anti-inflammatory/immunosuppressive agents such as cyclosporine, and lifitegrast. However, the recovery of patients with dry eye can take several years particularly if the symptoms are severe. This is because the present treatment approaches for dry eye are not based on its cause, e.g., the oxidative stress arising from the rapid increase in ROS. This work describes a new type of antioxidant made from pterostilbene (PS) and carboxyl-chitosan modified graphene (CG). The use of a hydrophilic two-dimensional CG nanosheet to improve the properties of PS is reported. Superior enhanced properties including better cellular permeability, long sustained release period (over 30 h), and antioxidant properties, were realized by using PS-CG. A hyperosmotic (HS) damaged human corneal epithelial cell (HCEC) model was used for antioxidant tests. This model has an intracellular ROS level 4 times more than that of a control group. The ROS content was declined efficiently to the same amount as normal cells in the PS-CG treated HS group. There was a significant decline in the content of lactate dehydrogenase (LDH) and the apoptosis rate of HCEC in the PS-CG treated HS group when compared to that seen in the HS model. Real-time polymerase chain reaction (PCR) and western blots (WB) were used to understand the antioxidant mechanism of PS-CG. The results showed that the antioxidant was working by activating the Keap1-Nrf2-ARE signalling pathway. In vivo testing testing using a dry eye mouse model suggested that the PS-CG acted as an efficient antioxidant. More tear production and healthier corneal and conjunctival epithelial cells were achieved when PC-CG was applied to this model. The use of PS-CG could be a new strategy for treating dry eye and other ocular diseases caused by ROS.

11.
Adv Healthc Mater ; 11(10): e2101667, 2022 05.
Article in English | MEDLINE | ID: mdl-35108456

ABSTRACT

The efficient regeneration of corneal nerves is of limited success in the field of ophthalmology. This work reports the use of a non-invasive electrical stimulation technique that uses a transparent graphene-based corneal stimulation electrode and that can achieve efficient regeneration of corneal nerves. The corneal stimulation electrode is prepared using electroactive nitrogen-containing conducting polymers such as polyaniline functionalized graphene (PAG). This composite can carry a high capacitive current. It can be used to tune transmembrane signaling pathways including calcium channels and the MAPK signaling pathway. Tuning can lead to the efficient regeneration of corneal damaged nerves after the surgery of laser in-situ keratomileusis (LASIK). The composite and its application reported have the potential to provide a new way to treat nerve-related injuries.


Subject(s)
Graphite , Cornea/surgery , Electrodes , Nerve Regeneration/physiology , Signal Transduction
12.
Macromol Biosci ; 21(7): e2100082, 2021 07.
Article in English | MEDLINE | ID: mdl-33984161

ABSTRACT

Antibiotic-resistant bacterial strains are a major cause of disease. They continue to remain a challenge in the clinic particularly in the vision system. For example, infectious endophthalmitis is a major blind-causing disease caused by bacteria. A highly efficient synergistic antibacterial treatment that uses a photothermal antibacterial therapeutic with a chemo-antibacterial therapeutic in a multifunctional nanocomposite is reported. It is prepared by immobilizing vancomycin onto the surface of a magnetic chitosan-graphene (VCM-MCG) composite. An antibacterial effect is achieved when VCM-MCG is applied. This effect is enhanced when the nanocomposites are irradiated with a near-infrared laser. Growth of gram-positive methicillin-resistant Staphylococcus aureus and gram-negative Escherichia coli bacteria are suppressed efficiently. Such a composite can help manage the control of pathogenic bacteria growth in the clinic.


Subject(s)
Graphite , Methicillin-Resistant Staphylococcus aureus , Anti-Bacterial Agents/pharmacology , Graphite/pharmacology , Magnetic Phenomena , Vancomycin/pharmacology
13.
ACS Biomater Sci Eng ; 6(1): 673-679, 2020 01 13.
Article in English | MEDLINE | ID: mdl-33463230

ABSTRACT

The noninvasive and real-time detection of glucose sugar from tears is promising for the early diagnosis and treatment of chronic diseases such as diabetes. However, its realization is a big challenge. A suitable biosensor electrode that can closely fit the eye and be electrochemically sensitive is still unrealized. In this work, nitrogen-doped graphene (N-G) was used as an ophthalmic electrode in a high-performance intraocular biosensor. The use of N-G has been reported elsewhere before as it is highly electroactive and so has a particular use in biosensors. We hereby present a novel procedure for making carboxylated chitosan-functionalized nitrogen-containing graphene (GC-COOH) by using a one-step ball-milling process. This process does not use toxic chemicals, flammable gases, or a high temperature. It is thus particularly easy to perform. The fabricated nanomaterial had a high electroactivity and was easily assembled as a glucose biosensor by the immobilization of glucose oxidase. The thus constructed biosensor has a high sensitivity at 9.7 µA mM-1 cm-2, a broad linear range at 12 mM, and a good detection limit of 9.5 µM. It was able to maintain this activity after a month of storage. We also report the intraocular use of this constructed biosensor. The as-prepared GC-COOH was found to be highly biocompatible to ophthalmologic cells such as corneal epithelial and retinal pigment epithelium cells. No change in the intraocular pressure or the corneal structure was measured in a New Zealand white rabbit model. The as-assembled sensor was worn by the animals for more than 24 h without undue impact. This result confirmed the biosensor's potential for intraocular application in the clinic. Its assembly into a useful sensor shown here has great potential to provide real-time monitoring of glucose levels in tear fluids of patients with high sugar levels.


Subject(s)
Biosensing Techniques , Chitosan , Graphite , Animals , Enzymes, Immobilized , Glucose , Humans , Nitrogen , Rabbits
14.
R Soc Open Sci ; 6(7): 190504, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31417748

ABSTRACT

Biodegradable random copolymers were successfully synthesized by melt polycondensation of poly(butylene succinate) (PBS) and salicylic acid (SA). The obtained copolymers were characterized by proton nuclear magnetic resonance spectroscopy. The effect of different SA contents on the properties of copolymers was investigated by universal testing machine, thermogravimetric analyser, differential scanning calorimetry and X-ray diffraction analysis. The results showed that the copolymers with 0.5% SA contents exhibited excellent elastic modulus (1413.0 MPa) and tensile strength (192.8 MPa), and similar thermal decomposition temperature (≈320°C) compared with pure PBS. By molecular docking simulations, it was proved that the degradability of copolymers was more effective than that of pure PBS with a binding energy of -5.77 kcal mol-1. PBS copolymers with a small amount of SA were not only biodegradable but could stimulate the growth of green vegetables. So biodegradable copolymers can be used over a wide range as they are environmentally friendly.

15.
Adv Healthc Mater ; 7(16): e1800377, 2018 08.
Article in English | MEDLINE | ID: mdl-29957869

ABSTRACT

The synthesis of transferrin (Tf)-modified pegylated graphene (PG) and its application as a highly efficient drug delivery carrier for therapy of Ocular Choroidal Melanoma-1 (OCM-1) cells is presented. For the first reported time, nanoscaled PG is prepared using an environmentally friendly ball-milling technique. The unique 2D nanostructure obtained using this PG synthesis approach offers considerable advantages in terms of drug loading and delivery, as well as the conjugation of Tf to PG providing a more targeted delivery vehicle. A highly efficient targeted pathway toward OCM-1 cells triggered by an affinity between Tf and Tf receptors expressed on the surface of OCM-1 cells is reported first here. PG-Tf is observed to easily anchor anticancer drugs such as doxorubicin via π-π stacking. This work performs a Transwell two cells coculture experiment, a 3D in vitro tumor model, and an in vivo mouse model with OCM-1 tumors to demonstrate the composite's therapeutic superiority over conventional systems for the targeted delivery and controlled release of antitumor drugs.


Subject(s)
Choroid Neoplasms/drug therapy , Graphite/chemistry , Melanoma/drug therapy , Transferrin/chemistry , Transferrin/therapeutic use , Animals , Cell Line , Cell Line, Tumor , Drug Delivery Systems/methods , Humans , Mice
16.
ACS Chem Neurosci ; 9(7): 1616-1624, 2018 07 18.
Article in English | MEDLINE | ID: mdl-29708326

ABSTRACT

Ethanol is a principle ingredient of alcoholic beverages with potential neurotoxicity and genotoxicity, and the ethanol-associated oxidative DNA damage in the central nervous system is well documented. Natural source compounds may offer new options to protect the brain against ethanol-induced genotoxicity. Veratrum maackii Regel is a toxic rangeland plant linked to teratogenicity which is also used in traditional Chinese medicine as "Lilu" and is reported to contain a family of compounds called stilbenes that can have positive biological activity. In this study, nine stilbenes were isolated from the aerial parts of V. maackii Regel, and their structures were identified as cis-mulberroside A (1), resveratrol-4,3'- O-ß-d-diglucopyranoside (2), mulberroside A (3), gentifolin K (4), resveratrol-3,5- O-ß-d-diglucopyranoside (5), oxyresveratrol- 4'- O-ß-d-glucopyranoside (6), oxyresveratrol-3- O-ß-d-glucopyranoside (7), oxyresveratrol (8), and resveratrol (9) using ESI-MS and NMR techniques. The total concentration of extracted compounds 2-9 was 2.04 mg/g, suggesting that V. maackii Regel is a novel viable source of these compounds. In an in vivo comet assay, compounds 1-9 were observed to decrease DNA damage in mouse cerebellum and cerebral cortex caused by acute ethanol administration. Histological observation also revealed decreased brain injury in mice administered with compounds 1-9 after acute ethanol administration. The protective effects of compound 6 were associated with increasing T-SOD and GSH-PX activities and a decrease in NO and MDA concentrations. These findings suggest that these compounds are potent inhibitors of ethanol-induced brain injury possibly via the inhibition of oxidative stress and may be valuable leads for future therapeutic development.


Subject(s)
Central Nervous System Depressants/adverse effects , DNA Damage/drug effects , Ethanol/adverse effects , Protective Agents/pharmacology , Stilbenes/pharmacology , Veratrum , Alcohol-Related Disorders/drug therapy , Alcohol-Related Disorders/metabolism , Alcohol-Related Disorders/pathology , Animals , Cerebellum/drug effects , Cerebellum/metabolism , Cerebellum/pathology , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Cerebral Cortex/pathology , Male , Mice , Molecular Structure , Neurons/drug effects , Neurons/metabolism , Neurons/pathology , Phototherapy , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Protective Agents/chemistry , Protective Agents/isolation & purification , Random Allocation , Stilbenes/chemistry , Stilbenes/isolation & purification
17.
Sci China Life Sci ; 61(4): 476-482, 2018 04.
Article in English | MEDLINE | ID: mdl-29675550

ABSTRACT

Surface plasmon resonance (SPR) nanosensors based on metallic nanohole arrays have been widely reported to detect binding interactions in biological specimens. A simple and effective method for constructing nanoscale arrays is essential for the development of SPR nanosensors. In this work, we report a one-step method to fabricate nanohole arrays by thermal nanoimprinting in the matrix of IPS (Intermediate Polymer Stamp). No additional etching process or supporting substrate is required. The preparation process is simple, time-saving and compatible for roll-to-roll process, potentially allowing mass production. Moreover, the nanohole arrays were integrated into detection platform as SPR sensors to investigate different types of biological binding interactions. The results demonstrate that our one-step method can be used to efficiently fabricate large-area and uniform nanohole arrays for biochemical sensing.


Subject(s)
Biosensing Techniques/instrumentation , Biosensing Techniques/methods , Gold/chemistry , Nanostructures/chemistry , Nanotechnology/instrumentation , Surface Plasmon Resonance , Models, Chemical , Nanostructures/ultrastructure , Protein Binding
18.
J Biomed Nanotechnol ; 14(8): 1420-1429, 2018 Aug 01.
Article in English | MEDLINE | ID: mdl-29903057

ABSTRACT

An efficient and targeted treatment for tumor cells is demonstrated. This targeting is based upon the strong affinity between hydroxyl-functional groups on graphene and acidic tumors. The hydroxylated graphene (GOH) with a unique 2D architecture further improve the targeting capacity of the system via an enhanced permeability and retention (EPR) process. Polyethylene glycol (PEG) was employed for better biocompatibility and the antitumor drug doxorubicin (DOX) was then incorporated. These additions created a biocompatible system with a superior pH-dependent drug release property. Its proficiency was due to its ability to pass through cell membranes via a process of endocytosis and exocytosis. The results from a Transwell co-culture system discovered that the PEG-GOH-DOX system had a large impact on tumor cell viability (less than 10% survived after treatment) and little influence on normal cells (more than 80% survived). An in vitro 3D tumor model study demonstrated that the size of the PEG-GOH-DOX treated tumor was 50% less than that of the pristine DOX treated tumor. In vivo data indicated that the PEG-GOH-DOX system was able to inhibit the size of tumors by a factor of 6.5 when compared to the untreated tumors.


Subject(s)
Graphite/chemistry , Antineoplastic Agents , Cell Line, Tumor , Cell Survival , Doxorubicin , Drug Delivery Systems , Humans , Polyethylene Glycols
19.
Case Rep Med ; 2016: 9675171, 2016.
Article in English | MEDLINE | ID: mdl-27895669

ABSTRACT

We describe a 59-year-old female who presented with ischaemic digits, preceded by a 6-month history of Raynaud's phenomenon affecting her fingers and toes. There were no clinical or laboratory features of primary vasculitis or connective tissue disease, Doppler imaging was normal, and bloods were unremarkable aside from a platelet count of 786 × 109/L (150-400) and white cells of 16 × 109/L (4-11). In view of the thrombocytosis a JAK2 mutation assay was requested which confirmed a JAK2 V617F mutation, suggesting essential thrombocytosis (ET) as the cause. She received treatment with hydroxycarbamide which normalised her platelet count and led to a complete resolution of her Raynaud's symptoms. Raynaud's phenomenon is a rare manifestation of ET. Myeloproliferative disorders such as ET should be considered in the differential diagnosis of Raynaud's phenomenon and vasculitis.

20.
BMJ Case Rep ; 20132013 Oct 31.
Article in English | MEDLINE | ID: mdl-24177456

ABSTRACT

This is a case of a 65-year-old man with seropositive erosive rheumatoid arthritis (RA), well controlled on methotrexate, sulfasalazine, low-dose prednisolone and monthly infusions of tocilizumab. He presented with a 3-week history of pain and swelling in his left knee, gradually increasing in severity with an inability to bear weight. He was systemically well with normal vital signs. Examination confirmed an effusion and aspiration was turbid in appearance. C reactive protein (CRP) was normal. He was treated empirically with antibiotics. Synovial fluid and blood cultures confirmed Staphylococcus aureus infection. He completed a 6 weeks course of antibiotics with complete resolution of symptoms. Throughout the treatment his CRP remained normal which is likely to have been the result of prior treatment with tocilizumab.


Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Antirheumatic Agents/administration & dosage , Arthritis, Infectious/blood , Arthritis, Rheumatoid/drug therapy , C-Reactive Protein/metabolism , Staphylococcal Infections/blood , Aged , Anti-Bacterial Agents/administration & dosage , Antibodies, Monoclonal, Humanized/adverse effects , Antirheumatic Agents/adverse effects , Arthritis, Infectious/drug therapy , Arthritis, Infectious/etiology , Arthritis, Rheumatoid/blood , Biomarkers/analysis , Biomarkers/metabolism , Humans , Knee Joint , Male , Methotrexate/administration & dosage , Prednisolone/administration & dosage , Risk Assessment , Sensitivity and Specificity , Severity of Illness Index , Staphylococcal Infections/drug therapy , Staphylococcal Infections/etiology , Sulfasalazine/administration & dosage , Treatment Outcome
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