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1.
J Colloid Interface Sci ; 512: 439-445, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29096104

RESUMEN

Herein, we demonstrate a coating-etching strategy to directly synthesize hollow Prussian blue (PB) nanocubes with well-dispersed Ag nanoparticles (denoted as Ag-HPB). The method is accomplished by introduction of PB precursors, K3Fe(CN)6 and Fe3+ into a reaction system containing AgNO3 and ascorbic acid, in which a series reactions contain formation of Ag nanoparticles, coating of PB on the nanoparticles, and diffusion of Ag into the PB frameworks occur. The strategy for preparation of the hollow structured Ag-HPB is intrinsically simple and does not require pre-preparation of any sacrificial templates or toxic etching agents. The obtained Ag-HPB nanocubes possess uniform size (69 nm), well-defined hollow structure, strong near-infrared photothermal conversion capacity, and excellent photoacoustic and magnetic resonance imaging abilities. Furthermore, an injectable photothermal implants are prepared for the first time by mixing the Ag-HPB nanocubes with clinically used biological glue, which significantly enhance photothermal anti-tumor efficacy, showing great potential for clinical tumor treatment.


Asunto(s)
Neoplasias de la Mama/terapia , Ferrocianuros/administración & dosificación , Hipertermia Inducida , Nanopartículas del Metal/administración & dosificación , Fototerapia , Plata/química , Animales , Neoplasias de la Mama/patología , Femenino , Ferrocianuros/química , Humanos , Nanopartículas del Metal/química , Ratones , Ratones Endogámicos BALB C , Prótesis e Implantes , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
2.
Theranostics ; 7(2): 466-481, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28255343

RESUMEN

A multifunctional nanotheranostic agent was developed by conjugating both hyaluronic acid and bovine serum albumin coated CuInS2-ZnS quantum dots onto the surface of magnetic Prussian blue nanoparticles. The obtained nanoagent could serve as an efficient contrast agent to simultaneously enhance near infrared (NIR) fluorescence and magnetic resonance (MR) imaging greatly. The coexistence of magnetic core and CD44 ligand hyaluronic acid was found to largely improve the specific uptake of the nanoagent by CD44 overexpressed HeLa cells upon applying an external magnetic field. Both NIR fluorescence and MR imaging in vivo proved high accumulation of the nanoagent at tumor site due to its excellent CD44 receptor/magnetic dual targeting capability. After intravenous injection of the nanoagent and treatment of external magnetic field, the tumor in nude mice was efficiently ablated upon NIR laser irradiation and the tumor growth inhibition was more than 89.95%. Such nanotheranostic agent is of crucial importance for accurately identifying the size and location of the tumor before therapy, monitoring the photothermal treatment procedure in real-time during therapy, assessing the effectiveness after therapy.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/terapia , Ferrocianuros/administración & dosificación , Nanopartículas de Magnetita/administración & dosificación , Fármacos Fotosensibilizantes/administración & dosificación , Puntos Cuánticos/administración & dosificación , Nanomedicina Teranóstica/métodos , Animales , Medios de Contraste/administración & dosificación , Modelos Animales de Enfermedad , Portadores de Fármacos/administración & dosificación , Células HeLa , Xenoinjertos , Humanos , Hipertermia Inducida , Rayos Láser , Campos Magnéticos , Imagen por Resonancia Magnética/métodos , Ratones Endogámicos BALB C , Ratones Desnudos , Imagen Óptica/métodos , Fotoquimioterapia
3.
Artículo en Alemán | MEDLINE | ID: mdl-25284353

RESUMEN

OBJECTIVE: This replication study investigated whether the 137caesium (137Cs) contamination of wild boars could be relevantly reduced under field conditions by adding ammonium-iron-hexa-cyanoferrate (AFCF; Prussian blue) to the food. MATERIAL AND METHODS: In 285 wild boars that had been shot in six Bavarian hunting territories during the season (November until May) between 01 November 2010 and 10 December 2011 137Cs contamination was analysed. Thirty-five animals originated from two hunting territories in which offered food had been supplemented with 1250 mg AFCF per kilogram food. RESULTS: The control animals showed a mean 137Cs contamination of 522 Bq/kg lean skeletal muscle meat. Direct (univariable) comparisons of the two experimental territories with the four control territories yielded a mean reduction in 137Cs contamination due to Prussian bluefeeding by -211 Bq/kg (p < 0.001). Multivariable models that took potential confounders into account (age, weight, sex, hunting date, territory) estimated the effect to be -344 Bq/kg (p < 0.05). CONCLUSION AND CLINICAL RELEVANCE: This replication study confirmed the finding of Kienzle et al. (12) who described a statistically significant reduction in 137Cs contamination by -380 Bq/kg due to the feeding of Prussian blue in other territories.


Asunto(s)
Alimentación Animal , Radioisótopos de Cesio/farmacocinética , Ferrocianuros/administración & dosificación , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Sus scrofa/metabolismo , Animales , Radioisótopos de Cesio/análisis , Contaminantes Ambientales/análisis , Contaminantes Ambientales/metabolismo , Contaminación Radiactiva de Alimentos/análisis , Contaminación Radiactiva de Alimentos/prevención & control , Carne/análisis , Músculo Esquelético/química , Porcinos
4.
Arch Insect Biochem Physiol ; 84(3): 157-73, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24123210

RESUMEN

The toxicity of potassium ferrocyanide (PFC) and protective effects of 2,4-dinitrophenol (DNP) under PFC treatment were tested on the Drosophila melanogaster model system. Fly larvae were raised on food supplemented with PFC at concentrations of 1.0 mM and mixtures with DNP in concentrations of 0.50 and 1.25 mM, either alone or in combination with 1.0 mM PFC. Food supplementation with PFC decreased larvae viability or pupation height, whereas when larvae were fed by PFC and DNP combination the decrease was less pronounced. Larval exposure to PFC and mixtures of DNP and PFC lowered activities of aconitase. Larval treatment with PFC resulted in higher carbonyl protein, uric acid, and low molecular mass thiols content and higher activity of thioredoxin reductase in adult flies, while DNP in mixtures with PFC relieved these effects. Furthermore, treatment with PFC/DNP mixtures resulted in higher activities of superoxide dismutase and glutathione-S-transferase. It is proposed that PFC toxicity is mainly related to the cyanide and iron ions, released during its decomposition. The potential mechanisms of protective DNP effects against PFC toxicity are discussed.


Asunto(s)
2,4-Dinitrofenol/farmacología , Antídotos/toxicidad , Antioxidantes/metabolismo , Drosophila melanogaster/efectos de los fármacos , Ferrocianuros/toxicidad , Desacopladores/farmacología , 2,4-Dinitrofenol/administración & dosificación , Alimentación Animal/análisis , Animales , Antídotos/administración & dosificación , Dieta , Suplementos Dietéticos/análisis , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimología , Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/fisiología , Ferrocianuros/administración & dosificación , Larva/efectos de los fármacos , Larva/enzimología , Larva/crecimiento & desarrollo , Larva/fisiología , Estrés Oxidativo/efectos de los fármacos , Pupa/efectos de los fármacos , Pupa/enzimología , Pupa/crecimiento & desarrollo , Pupa/fisiología , Desacopladores/administración & dosificación , Desacopladores/metabolismo
5.
Health Phys ; 99(3): 420-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20699707

RESUMEN

Novel decorporation agents are being developed to protect against radiological terrorist attacks. These sorbents, known as the self-assembled monolayer on mesoporous supports (SAMMS), are hybrid materials where differing organic moieties are grafted onto mesoporous silica (SiO(2)). In vitro experiments focused on the evaluation and optimization of SAMMS for capturing radiocesium ((137)Cs); therefore, based on these studies, a ferrocyanide copper (FC-Cu-EDA)-SAMMS was advanced for in vivo evaluation. In vivo experiments were conducted comparing the performance of the SAMMS vs. insoluble Prussian blue. Groups of jugular cannulated rats (4/treatment) were evaluated. Animals in Group I were administered (137)Cs chloride (approximately 40 microg kg(-1)) by intravenous (i.v.) injection or oral gavage; Group II animals were administered pre-bound (137)Cs-SAMMS or sequential Cs chloride + SAMMS (approximately 61 ng kg(-1)) by oral gavage; and Group III was orally administered (137)Cs chloride (approximately 61 ng kg(-1)) followed by either 0.1 g of SAMMS or Prussian blue. Following dosing, the rats were maintained in metabolism cages for 72 h and blood, urine, and fecal samples were collected for (137)Cs analysis (gamma counting). Rats were then humanely euthanized, and selected tissues analyzed. Orally administered (137)Cs chloride was rapidly and well absorbed (approximately 100% relative to i.v. dose), and the pharmacokinetics (blood, urine, feces, and tissues) were very comparable to the i.v. dose group. For both exposures the urine and feces accounted for 20 and 3% of the dose, respectively. The prebound (137)Cs-SAMMS was retained primarily within the feces (72% of the dose), with approximately 1.4% detected in the urine, suggesting that the (137)Cs remained tightly bound to SAMMS. SAMMS and Prussian blue both effectively captured available (137)Cs in the gut with feces accounting for 80-88% of the administered dose, while less than 2% was detected in the urine. This study suggests that the functionalized SAMMS outperforms Prussian blue in vitro at low pH, but demonstrates comparable in vivo sequestration efficacy at low exposure concentrations. The comparable response may be the result of the low (137)Cs chloride dose and high sorbent dosage that was utilized. Future studies are planned to optimize the performance of SAMMS in vivo over a broader range of doses and conditions.


Asunto(s)
Cesio/aislamiento & purificación , Descontaminación/métodos , Ferrocianuros/farmacología , Nanopartículas , Dióxido de Silicio/farmacología , Administración Oral , Animales , Cesio/sangre , Cesio/metabolismo , Cesio/orina , Cloruros , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Heces/química , Ferrocianuros/administración & dosificación , Ferrocianuros/química , Concentración de Iones de Hidrógeno , Inyecciones Intravenosas , Masculino , Porosidad , Ratas , Ratas Sprague-Dawley , Dióxido de Silicio/administración & dosificación , Dióxido de Silicio/química , Factores de Tiempo
6.
Clin Toxicol (Phila) ; 47(6): 592-4, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19586358

RESUMEN

INTRODUCTION: Nonradioactive cesium chloride (CsCl) is used by some alternative medicine advocates as a treatment for cancer. The therapy was proven to be neither safe nor effective. Chronic use of CsCl has resulted in cases with severe cardiotoxicity. CASE REPORT: A 65-year-old lady presented to our hospital's accident and emergency department with recurrent syncope attacks. Electrocardiogram monitoring showed QT prolongation and transient Torsades de Pointes (TDP) ventricular tachycardia. She was taking anticancer naturopathic drugs for 6 weeks before admission. One of her naturopathic drugs was subsequently confirmed containing 89% CsCl by weight. Besides conventional treatment of QT prolongation and TDP, the patient was given a 4-week course of oral Prussian blue to enhance gastrointestinal elimination of cesium. The serum half-life of cesium was reduced from 61.7 to 29.4 days after the use of Prussian blue. QT prolongation was normalized in 27 days. DISCUSSION: To our knowledge, this is the first published case of nonradioactive cesium poisoning treated with Prussian blue. A transient rise in serum cesium level was observed during Prussian blue therapy. Possible explanations for this observation include poor drug compliance during outpatient treatment and redistribution of cesium from body stores. CONCLUSION: Nonradioactive CsCl poisoning can result in severe cardiotoxicity with QT prolongation and TDP ventricular tachycardia. The key points in the management of nonradioactive cesium poisoning include cessation of cesium exposure, vigorous electrolytes replacement, and oral Prussian blue therapy.


Asunto(s)
Antineoplásicos/envenenamiento , Cesio/envenenamiento , Cloruros/envenenamiento , Terapias Complementarias/efectos adversos , Torsades de Pointes/inducido químicamente , Anciano , Antídotos/administración & dosificación , Quimioterapia Combinada , Electrocardiografía , Electrólitos/administración & dosificación , Femenino , Ferrocianuros/administración & dosificación , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Neoplasias del Recto/tratamiento farmacológico , Neoplasias del Recto/patología , Taquicardia Ventricular/inducido químicamente , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/terapia , Torsades de Pointes/diagnóstico , Torsades de Pointes/terapia , Resultado del Tratamiento
7.
Sci Total Environ ; 137: 235-48, 1993 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-8248770

RESUMEN

The same chemicals can be used for reduction of radionuclide transfer to animals whether kept on farms or grazing in semi-natural and natural habitats. However, different techniques are required for administration of the active compounds. Dairy ruminants may be treated effectively by inclusion of chemicals in supplemental concentrates. Practical experience gained after the Chernobyl accident has shown that both clay minerals and hexacyanoferrates are effective in preventing high radiocaesium levels in animal products. Chemicals such as bentonite clays and CaCO3, used for reduction of 137Cs and 90Sr transfer respectively, must be fed in hectogram quantities and are only practical for dairy animals in semi-natural ecosystems. Salt licks and sustained release boli with hexacyanoferrates as caesium binders have been developed and used successfully after the Chernobyl accident for meat producing cattle, sheep and reindeer which graze freely for extended periods. Daily doses of 25-300 mg in sheep and 250-2000 mg in cows reduces 137Cs accumulation 2-10-fold. Binders for 90Sr have not been tested in grazing animals. Stable iodine could be provided in salt licks and indwelling rumen boli at rates required to block radioiodine uptake by the thyroid gland. Boli and salt licks are highly cost effective in reducing doses to man when compared to interdiction of food from farm animals.


Asunto(s)
Radioisótopos de Cesio/farmacocinética , Quelantes/administración & dosificación , Contaminación Radiactiva de Alimentos/prevención & control , Silicatos de Aluminio/administración & dosificación , Animales , Bovinos , Arcilla , Ferrocianuros/administración & dosificación , Carne , Leche , Reno , Ovinos
8.
Vopr Pitan ; (5-6): 62-5, 1992.
Artículo en Ruso | MEDLINE | ID: mdl-1296369

RESUMEN

The paper reports a new technique of obtaining radioactive Cs-free meat in the regions contaminated with radionuclides as a result of Chernobyl accident. The method is based on specific digestion features of ruminant animals. Ferriferrocyanide compounds are proposed as sorbents. Ferrocene is most efficient when introduced into mixed feed (1-3 g/day for sheep, 3-5 g/day for calves and young bulls) once a day. After that the animals can be fed radioactively contaminated forage and graze on contaminated land.


Asunto(s)
Accidentes , Ferrocianuros/administración & dosificación , Contaminación Radiactiva de Alimentos/prevención & control , Carne/efectos de la radiación , Reactores Nucleares , Centrales Eléctricas , Alimentación Animal , Animales , Bovinos , Radioisótopos de Cesio/aislamiento & purificación , Evaluación Preclínica de Medicamentos , Enteroadsorción/métodos , Enteroadsorción/veterinaria , Carne/normas , Ovinos , Ucrania
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