14,254 results match your criteria Toxicity Iron


Penetration and photodynamic ablation of drug-resistant biofilm by cationic Iron oxide nanoparticles.

J Control Release 2022 Jun 24. Epub 2022 Jun 24.

School of Pharmaceutical Sciences, Nanjing Tech University, Nanjing 211816, PR China; State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, PR China. Electronic address:

As we step into the post-antibiotic era, the accelerated emergence of antibiotic-resistant pathogenic bacteria poses an increasingly serious threat to public health. The formation of antibiotic-resistant biofilms further challenges currently available drugs and treatment options, calling for novel strategies for effective ablation of such biofilm with minimal concern on safety and development of resistance. Herein, we report a novel type of photodynamic nanoagent, composed of chlorin e6 (Ce6)-loaded water-soluble chitosan-coated iron oxide nanoparticles (named [email protected]), for drug-resistant bacteria killing and biofilm eradication. Read More

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Assessment of the toxicity of a mixture of five rare earth elements found in aquatic ecosystems in Hydra vulgaris.

Ecotoxicol Environ Saf 2022 Jun 24;241:113793. Epub 2022 Jun 24.

Aquatic Contaminants Research Division, Environment and Climate Change Canada, 105 McGill street, 7th Floor, Montréal, QC H2Y 2E7, Canada.

Rare earth elements (REEs) are considered critical elements for technology and their extraction through mining activities is expected to increase in the future. Due to their chemical similarities, they often co-occur in minerals and thus their ecotoxicity should be assessed as a group/family. However, the available ecotoxicological studies focused mainly on the evaluation of the potential toxicological impacts of individual REEs rather than their mixtures. Read More

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Life cycle assessment of zinc and iron recovery from spent pickling acids by membrane-based solvent extraction and electrowinning.

J Environ Manage 2022 Jun 24;318:115567. Epub 2022 Jun 24.

Departamento de Ingenierías Química y Biomolecular, Universidad de Cantabria, Avda. de Los Castros s.n, 39005, Santander, Spain. Electronic address:

In this paper we conducted a life cycle assessment to evaluate the environmental performance of the valorization of spent pickling acid (SPA) generated in the hot-dip galvanizing (HDG) process. We analyzed the environmental impacts of treating one m of SPA, comparing the reference treatment consisting of neutralization, precipitation, stabilization, and landfilling of the metallic sludge (scenario #1), with the innovative LIFE2ACID technology (scenario #2) that produces secondary zinc and iron chloride in solution through non-dispersive solvent extraction (NDSX) and electrowinning (EW). The results showed that the materials credits achieved by the implementation of LIFE2ACID technology turned most of the impact categories evaluated (toxicity, acidification, eutrophication, ozone depletion, etc. Read More

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Bulk flotation followed by selective leaching with biogenic ferric iron is a promising solution for eco-friendly processing of complex sulfidic ores.

J Environ Manage 2022 Jun 24;318:115587. Epub 2022 Jun 24.

Winogradsky Institute of Microbiology, Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences, Leninsky Ave., 33, bld. 2, 119071, Moscow, Russia. Electronic address:

The development of cost-effective environmentally friendly technologies is of current importance for the intensification of metal recovery. Here, we propose a new direction in the use of a two-step process for the treatment of complex sulfidic ores. In the first step, ore flotation allows the obtainment of a bulk copper-zinc concentrate and low-toxicity waste. Read More

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A RETROSPECTIVE STUDY OF HEPATIC HEMOSIDEROSIS AND IRON STORAGE DISEASE IN SEVERAL CAPTIVE AND FREE-RANGING AVIAN SPECIES.

J Zoo Wildl Med 2022 Jun;53(2):455-460

Departamento de Clínica e Cirurgia Veterinárias, Escola de Veterinária, Universidade Federal de Minas Gerais, Avenida Presidente Antônio Carlos, 31270-901, Brazil,

Some wild species of mammals and birds are prone to excessive iron accumulation, especially when maintained in human care. Hemosiderosis is the process of intracellular accumulation of iron without evidence of toxicity, whereas hemochromatosis is characterized by severe iron accumulation with accompanying organ damage. Iron storage disease (ISD) occurs when organ damage is severe and causing clinical signs. Read More

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Ru(II) photocages enable precise control over enzyme activity with red light.

Nat Commun 2022 Jun 25;13(1):3636. Epub 2022 Jun 25.

Department of Chemistry, University of Kentucky, Lexington, KY, 40506, USA.

The cytochrome P450 family of enzymes (CYPs) are important targets for medicinal chemistry. Recently, CYP1B1 has emerged as a key player in chemotherapy resistance in the treatment of cancer. This enzyme is overexpressed in a variety of tumors, and is correlated with poor treatment outcomes; thus, it is desirable to develop CYP1B1 inhibitors to restore chemotherapy efficacy. Read More

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Optical coherence tomography findings in patients with transfusion-dependent β-thalassemia.

BMC Ophthalmol 2022 Jun 24;22(1):279. Epub 2022 Jun 24.

Poostchi Ophthalmology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.

Background: Structural ophthalmologic findings have been reported in patients with β-thalassemia due to chronic anemia, iron overload, and iron chelation therapy toxicity in few previous studies. We aimed to investigate structural ocular findings and their relationship with hematological parameters in patients with transfusion-dependent β-thalassemia (TDT).

Methods: In this cross-sectional study, from January 2018 to January 2019, 39 patients with TDT over the age of 18 participated. Read More

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Modulation of Pulmonary Toxicity in Metabolic Syndrome Due to Variations in Iron Oxide Nanoparticle-Biocorona Composition.

Nanomaterials (Basel) 2022 Jun 11;12(12). Epub 2022 Jun 11.

School of Health Sciences, College of Health and Human Sciences, Purdue University, West Lafayette, IN 47907, USA.

Nanoparticles (NPs) interact with biomolecules by forming a biocorona (BC) on their surface after introduction into the body and alter cell interactions and toxicity. Metabolic syndrome (MetS) is a prevalent condition and enhances susceptibility to inhaled exposures. We hypothesize that distinct NP-biomolecule interactions occur in the lungs due to MetS resulting in the formation of unique NP-BCs contributing to enhanced toxicity. Read More

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Biosynthesis of Iron Oxide Nanoparticles: Physico-Chemical Characterization and Their In Vitro Cytotoxicity on Healthy and Tumorigenic Cell Lines.

Nanomaterials (Basel) 2022 Jun 10;12(12). Epub 2022 Jun 10.

Department of Toxicology and Drug Industry, Faculty of Pharmacy, "Victor Babes" University of Medicine and Pharmacy Timisoara, 2nd Eftimie Murgu Square, RO-300041 Timisoara, Romania.

Iron oxide nanoparticles were synthesized starting from two aqueous extracts based on L. leaf and stems, employing a simplest, eco-friendliness and low toxicity method-green synthesis. The nanoparticles were characterized by powder X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR), X-ray fluorescence analysis (XRF), thermal analysis (TG/DSC), and scanning electron microscopy (SEM). Read More

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Dispersion Stability of 14 Manufactured Nanomaterials for Ecotoxicity Tests Using .

Int J Environ Res Public Health 2022 Jun 10;19(12). Epub 2022 Jun 10.

Department of Chemical and Molecular Engineering, Hanyang University, 55 Hanyangdaehakro, Sangrok-gu, Ansan 15588, Korea.

The development of nanotechnology has increased concerns about the exposure of ecosystems to manufactured nanomaterials, the toxicities of which are now being researched. However, when manufactured nanomaterials are mixed with algae in a culture medium for ecotoxicity tests, the results are vulnerable to distortion by an agglomeration phenomenon. Here, we describe a dispersion method commonly applicable to ecotoxicity tests for the 14 types of manufactured nanomaterials specified by the Organisation of Economic Co-operation and Development's Sponsorship Programme, namely aluminum oxide (AlO), carbon black, single-walled carbon nanotubes (SWCNTs), multi-walled carbon nanotubes (MWCNTs), cerium oxide (CeO), dendrimers, fullerene, gold (Au), iron (Fe), nanoclays, silver (Ag), silicon dioxide (SiO), titanium dioxide (TiO), and zinc oxide (ZnO). Read More

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Iron Oxide Nanoparticles for Visualization of Prostate Cancer in MRI.

Cancers (Basel) 2022 Jun 13;14(12). Epub 2022 Jun 13.

Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Charitéplatz 1, 10117 Berlin, Germany.

Prostate cancer (PCa) is one of the most common cancers in men. For detection and diagnosis of PCa, non-invasive methods, including magnetic resonance imaging (MRI), can reduce the risk potential of surgical intervention. To explore the molecular characteristics of the tumor, we investigated the applicability of ferumoxytol in PCa in a xenograft mouse model in two different tumor volumes, 500 mm and 1000 mm. Read More

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Phosphoproteomic analysis of FAC overload-triggered human hepatic cells reveals G2/M phase arrest.

Biochem Biophys Res Commun 2022 Jun 10;619:62-67. Epub 2022 Jun 10.

Chenghai Dongli Central Health Centre, Shantou, 515829, China.

Hepatic iron overload is a universal phenomenon in patients with myelodysplastic syndromes (MDS) who undergo bone marrow transplantation and may experience the toxicity of peri- and post-bone marrow transplantation. To clarify the mechanisms of iron overload-triggered liver injury, we determined the effects of iron overload on changes in protein phosphorylation in human hepatocyte cell line HH4 in vitro by using a phosphoproteomics approach. The hepatocytes were exposed to high concentrations of ferric ammonium citrate (FAC) to build up an iron overload model in vitro. Read More

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Evaluating the Potential Health Risks of Selected Heavy Metals across Four Wastewater Treatment Water Works in Durban, South Africa.

Toxics 2022 Jun 20;10(6). Epub 2022 Jun 20.

Environmental Pollution and Remediation Research Group, Department of Chemical Engineering, Mangosuthu University of Technology, Durban 4031, South Africa.

Poor and inadequate sanitation systems have been considered not only a human health issue, but also an environmental threat that instigates climate change. Nine heavy metals-arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn)-were evaluated in influent and effluent water samples from four wastewater treatment plants in the Durban metropolis, KwaZulu-Natal, South Africa. The results indicate that the mean concentrations of all the heavy metals in the influent samples ranged from 0. Read More

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Characterization of the NRAMP Gene Family in the Arbuscular Mycorrhizal Fungus .

J Fungi (Basel) 2022 May 31;8(6). Epub 2022 May 31.

Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín, CSIC, C. Profesor Albareda 1, 18008 Granada, Spain.

Transporters of the NRAMP family are ubiquitous metal-transition transporters, playing a key role in metal homeostasis, especially in Mn and Fe homeostasis. In this work, we report the characterization of the NRAMP family members (, , and ) of the arbuscular mycorrhizal (AM) fungus Phylogenetic analysis of the NRAMP sequences of different AM fungi showed that they are classified in two groups, which probably diverged early in their evolution. Functional analyses in yeast revealed that encodes a protein mediating Mn and Fe transport from the environment. Read More

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Luminescent Composite Carbon/SiO Structures: Synthesis and Applications.

Biosensors (Basel) 2022 Jun 6;12(6). Epub 2022 Jun 6.

Department of Inorganic Chemistry, Chemical Institute, Saratov State University, Astrakhanskaya Street 83, 410012 Saratov, Russia.

Luminescent carbon nanostructures (CNSs) have attracted great interest from the scientific community due to their photoluminescent properties, structural features, low toxicity, and a great variety of possible applications. Unfortunately, a few problems hinder their further development. These include the difficulties of separating a mixture of nanostructures after synthesis and the dependence of their properties on the environment and the aggregate state. Read More

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Norcantharidin down-regulates iron contents in the liver and spleen of lipopolysaccharide-treated mice.

Redox Rep 2022 Dec;27(1):119-127

Research Center for Medicine and Biology, Zunyi Medical University, Zunyi, People's Republic of China.

Objective: The inhibiting effect of Norcantharidin (NCTD) on IL-6 (interleukin-6) and STAT3 and the involvement of the IL-6/STAT3 pathway in hepcidin expression prompted us to speculate that NCTD could affect iron metabolism.

We examined the effects of NCTD on serum iron (SI) and transferrin (Tf) saturation, iron and ferritin light chain (FTL), transferrin receptor 1 (TfR1), divalent metal transporter 1 (DMT1), ferroportin 1 (Fpn1), iron regulatory protein 1 (IRP1) and hepcidin, as well as IL-6 and STAT3 in the liver, spleen and duodenum of mice treated with lipopolysaccharide (LPS) in vivo, using RT-PCR, Western blotting and immunofluorescence analysis.

NCTD could increase SI and Tf saturation and reduce tissue iron and FTL content by affecting expression of cell-iron transport proteins TfR1, DMT1 and Fpn1. Read More

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December 2022

Biodegradable Zn-Cu-Fe Alloy as a Promising Material for Craniomaxillofacial Implants: An Investigation into Degradation Behavior, Cytotoxicity, and Hemocompatibility.

Front Chem 2022 6;10:860040. Epub 2022 Jun 6.

State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases, Department of Preventive Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China.

Zinc-based nanoparticles, nanoscale metal frameworks and metals have been considered as biocompatible materials for bone tissue engineering. Among them, zinc-based metals are recognized as promising biodegradable materials thanks to their moderate degradation rate ranging between magnesium and iron. Nonetheless, materials' biodegradability and the related biological response depend on the specific implant site. Read More

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Peroxydisulfate activation by nano zero-valent iron graphitized carbon materials for ciprofloxacin removal: Effects and mechanism.

J Hazard Mater 2022 Jun 15;437:129392. Epub 2022 Jun 15.

Guangdong Industrial Contaminated Site Remediation Technology and Equipment Engineering Research Center, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.

Since the discovery of the potential hazards of ciprofloxacin (CIP) to the ecosystem and human health, there has been an urgent need to develop effective technologies to solve the severe issue. In this work, the nanozero-valent iron graphitized carbon matrix ([email protected]) were prepared via a hydrothermal method to activate peroxydisulfate (PDS) for degradation of CIP. Specifically, 0. Read More

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Photoinduced Iron-Catalyzed ATRP of Renewable Monomers in Low-Toxicity Solvents: A Greener Approach.

ACS Macro Lett 2022 Jun 22:841-846. Epub 2022 Jun 22.

-Laboratory of Polymeric Materials, Department of Materials, ETH Zurich, Vladimir-Prelog-Weg 5, Zurich 8093, Switzerland.

Producing polymers from renewable resources via more sustainable approaches has become increasingly important. Herein we present the polymerization of monomers obtained from biobased renewable resources, employing an environmentally friendly photoinduced iron-catalyzed atom transfer radical polymerization (ATRP) in low-toxicity solvents. We demonstrate that renewable monomers can be successfully polymerized into sustainable polymers with controlled molecular weights and narrow molar mass distributions ( as low as 1. Read More

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90Y-CA/SPIONs for dual magnetic hyperthermia-radionuclide nano-brachytherapy of solid tumours.

Nanotechnology 2022 Jun 21. Epub 2022 Jun 21.

Radioisotopes, Vinca Institute for nuclear sciences Department of radioisotopes, Mike Petrovica Alasa 12-14, Belgrade, Belgrade, 11001, SERBIA.

Radiolabelled superparamagnetic iron oxide nanoparticles (SPIONs) are promising nanomaterial for development of dual radiation/hyperthermia cancer therapy. To that purpose, flower-shaped SPIONs with an exceptional heating capability were synthesised and coated with citrate, dextran or (3-aminopropyl)triethoxysilane. Both non-coated and coated SPIONs were nontoxic to CT-26 mouse colon cancer cells up to 1. Read More

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Ferroptosis as a mechanism of non-ferrous metal toxicity.

Arch Toxicol 2022 Jun 21. Epub 2022 Jun 21.

Laboratory of Molecular Dietetics, IM Sechenov First Moscow State Medical University (Sechenov University), 119435, Moscow, Russia.

Ferroptosis is a recently discovered form of regulated cell death, implicated in multiple pathologies. Given that the toxicity elicited by some metals is linked to alterations in iron metabolism and induction of oxidative stress and lipid peroxidation, ferroptosis might be involved in such toxicity. Although direct evidence is insufficient, certain pioneering studies have demonstrated a crosstalk between metal toxicity and ferroptosis. Read More

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Cr(VI) immobilization in soil using lignin hydrogel supported nZVI: Immobilization mechanisms and long-term simulation.

Chemosphere 2022 Jun 17;305:135393. Epub 2022 Jun 17.

College of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai, 200444, China.

A novel nanocomposite, named as [email protected], was prepared by nanoscale zero-valent iron (nZVI) supported on lignin hydrogel and was used in the remediation of Cr(VI)-contaminated soil collected from an industrial site. Meanwhile, scanning electron microscopy with energy dispersive X-ray (SEM-EDX) and X-ray diffractometry (XRD) results determined that nZVI nanoparticles disperse uniformly on hydrogel. After the 14 days remediation, the immobilization efficiency of Cr(VI) could reach over 87% in the treatment of 3% (w/w%) [email protected] and 26% in the treatment of bare-nZVI. Read More

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[Role of ferroptosis in cerebellar injury of mice following lead exposure].

Wei Sheng Yan Jiu 2022 May;51(3):443-469

School of Public Health, North China University of Science and Technology, Tangshan 063210, China Laboratory Animal Center, North China University of Science and Technology, Tangshan 063210, China.

Objective: To investigate the role of ferroptosis in cerebellar injury of mice following lead exposure.

Methods: A total of forty SPF C57 mice were randomly divided into control group, low-dose lead exposure group, middle-dose lead exposure group and high-dose lead exposure group, with 10 mice in each group. Mice in three lead exposure groups were given 0. Read More

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A white paper on Phospholipid Hydroperoxide Glutathione Peroxidase (GPx4) forty years later.

Free Radic Biol Med 2022 Jun 16;188:117-133. Epub 2022 Jun 16.

Department of Molecular Medicine, Viale G. Colombo, 3, University of Padova, 35121, Padova, Italy. Electronic address:

The purification of a protein inhibiting lipid peroxidation led to the discovery of the selenoperoxidase GPx4 forty years ago. Thus, the evidence of the enzymatic activity was reached after identifying the biological effect and unambiguously defined the relationship between the biological function and the enzymatic activity. In the syllogism where GPx4 inhibits lipid peroxidation and its inhibition is lethal, cell death is operated by lipid peroxidation. Read More

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Loquat (Eriobotrya japonica (Thunb) Lindl.): Evaluation of nutritional value, polyphenol composition, antidiabetic effect, and toxicity of leaf aqueous extract.

J Ethnopharmacol 2022 Jun 17;296:115473. Epub 2022 Jun 17.

Biochemistry and Natural Substances Team, Department of Biology, Faculty of Sciences & Techniques, University Moulay Ismail, Errachidia, 52000, Morocco. Electronic address:

Ethnopharmacological Relevance: Loquat (Eriobotrya japonica (Thunb.) Lindl.) is an evergreen tree native to China, which is introduced in many Mediterranean countries. Read More

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Advancing chemical hazard assessment with decision analysis: A case study on lithium-ion and redox flow batteries used for energy storage.

J Hazard Mater 2022 Jun 7;437:129301. Epub 2022 Jun 7.

Department of Materials Science and Engineering, University of California, Irvine, CA, United States. Electronic address:

Batteries are important for promoting renewable energy, but, like most engineered products, they contain multiple hazardous materials. The purpose of this study is to evaluate industrial-scale batteries using GreenScreen® for Safer Chemicals, an established chemical hazard assessment (CHA) framework, and to develop a systematic, transparent methodology to quantify the CHA results, harmonize them, and aggregate them into single-value hazard scores, which can facilitate quantitative comparison and a robust evaluation of data gaps, inconsistencies, and uncertainty through the implementation of carefully selected scenarios and stochastic multicriteria acceptability analysis (SMAA). Using multiple authoritative toxicity data sources, six battery products are evaluated: three lithium-ion batteries (lithium iron phosphate, lithium nickel cobalt manganese hydroxide, and lithium manganese oxide), and three redox flow batteries (vanadium redox, zinc-bromine, and all-iron). Read More

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Toxicity of Nanoparticles of AgO, La₂O₃, CuO, AgO-Fe₃O₄, Ag-Graphene, and GO-Cu-AgO to the Fungus Y12 Isolated from Degraded Biodiesel and the Bacterium .

J Biomed Nanotechnol 2022 Mar;18(3):928-938

College of Agriculture and Biology, Zhongkai University of Agriculture and Engineering, Guangzhou, Guangdong, 510225, China.

Y12 ( Y12), a fungal isolated from biodiesel caused serious biodiesel contamination and resulting in biofouling and corrosion, especially during storage. Nanoparticles (NPs) composed of silver, copper, iron, and graphene or their binary mixtures were examined as environmental inhibitors against the fungus Y12, a biodiesel contaminant. Exposure of Y12 and () to low concentrations of Ag-based nanoparticles (from 0. Read More

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Phenotypic and Molecular Characterization of K54-ST29 Hypervirulent Causing Multi-System Infection in a Patient With Diabetes.

Front Microbiol 2022 31;13:872140. Epub 2022 May 31.

Intensive Care Department of Taian City Central Hospital, Tai'an, China.

Worldwide, hypervirulent (hvKp) is one of the leading causes of multisystem infection. Serotype K54 has also been considered as one of the hvKp-associated capsular types that are rarely reported. In this study, we reported a K54-ST29 hvKp isolated from a 58-year-old male patient with diabetes in a teaching hospital in China. Read More

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Impact of surface chemistry of ultrasmall superparamagnetic iron oxide nanoparticles on protein corona formation and endothelial cell uptake, toxicity, and barrier function.

Toxicol Sci 2022 Jun 16. Epub 2022 Jun 16.

Division of Biology, Chemistry and Materials Science, Office of Science and Engineering, Laboratories, Center for Devices and Radiological Health, US Food and Drug, Administration, Silver Spring, Maryland.

Ultrasmall superparamagnetic iron oxide nanoparticles (USPION) have been investigated for biomedical applications, including novel contrast agents, magnetic tracers for tumor imaging, targeted drug delivery vehicles, and magneto-mechanical actuators for hyperthermia and thrombolysis. Despite significant progress, recent clinical reports have raised concerns regarding USPION safety related to endothelial cell dysfunction; however, there is limited information on factors contributing to these clinical responses. The influence of USPION surface chemistry on nanoparticle interactions with proteins may impact endothelial cell function leading to adverse responses. Read More

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The improved killing of both androgen-dependent and independent prostate cancer cells by etoposide loaded SPIONs coupled with NIR irradiation.

Biomater Sci 2022 Jun 15. Epub 2022 Jun 15.

Department of Chemistry, Koc University, Rumelifeneri Yolu, Sariyer, Istanbul 34450, Türkiye.

Etoposide (Eto) is a toxic drug that shows promise in treating prostate cancer (PCa) but confers significant side effects, and has poor solubility and bioavailability. Nanoparticles are quite successful in overcoming such problems. Multifunctional nanoparticles that provide an opportunity to perform combination therapy have attracted great interest in recent years. Read More

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