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1.
Am J Hematol ; 99(6): 1077-1083, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38476079

RESUMO

Restless legs syndrome (RLS) is a neurological disorder that can have a profound effect on sleep and quality of life. Idiopathic RLS is associated with brain iron insufficiency despite normal peripheral iron stores. There is, however, a five- to six-fold increase in prevalence of RLS in patients with iron deficiency anemia (IDA). Several open-label trials have demonstrated symptomatic improvement in RLS following treatment of IDA using oral or intravenous iron supplementation. To date, there have been no randomized double-blind controlled trials of intravenous iron compared with oral iron for the treatment of RLS patients with IDA. In the current study, oral ferrous sulfate and ferumoxytol were compared for efficacy and speed of response for treatment of RLS occurring in patients with IDA. The planned recruitment for this study was 70 patients with RLS and IDA, to be randomly assigned 1:1 to oral or intravenous iron, using double-blind, double-dummy procedures. At Week 6, the primary outcomes of Clinical Global Impression-Improvement score and change from baseline in the International Restless Legs Syndrome Study Group rating scale score were assessed. Due to challenges, performing the clinical trial during the COVID-19 pandemic, final-week data were found missing for 30 patients. As a result, in order to maintain the prespecified statistical analysis, an additional 30 patients were recruited. Both IV and oral iron were associated with a marked improvement in RLS symptoms, with no statistically significant difference between treatment groups. No serious adverse events were observed in either treatment group.


Assuntos
Administração Intravenosa , Anemia Ferropriva , Compostos Ferrosos , Síndrome das Pernas Inquietas , Humanos , Síndrome das Pernas Inquietas/tratamento farmacológico , Anemia Ferropriva/tratamento farmacológico , Administração Oral , Método Duplo-Cego , Masculino , Feminino , Projetos Piloto , Pessoa de Meia-Idade , Compostos Ferrosos/administração & dosagem , Compostos Ferrosos/uso terapêutico , Compostos Ferrosos/efeitos adversos , Adulto , Idoso , Resultado do Tratamento , Óxido Ferroso-Férrico/administração & dosagem , Óxido Ferroso-Férrico/uso terapêutico , Óxido Ferroso-Férrico/efeitos adversos , Ferro/administração & dosagem , Ferro/uso terapêutico
2.
Ren Fail ; 44(1): 94-102, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35156909

RESUMO

PURPOSE: To evaluate the efficacy of ferumoxytol, relative to conventional iron supplement formulations, on hemoglobin levels, ferritin level, and adverse event incidence in chronic kidney disease patients. METHODS: We performed a systematic search of six academic databases (EMBASE, CENTRAL, Scopus, PubMed, Web of sciences, and MEDLINE), adhering to PRISMA guidelines. We performed a meta-analysis on relevant studies to evaluate the overall influence of ferumoxytol, relative to conventional iron supplement formulations, on hemoglobin levels, ferritin level, and treatment related treatment emergent adverse events (TEAEs) incidence in chronic kidney disease patients. RESULTS: Seven eligible studies were identified from a total of 1397 studies. These studies contained data on 3315 participants with chronic kidney disease (mean age: 59.2 ± 4.6 years). A meta-analysis revealed that ferumoxytol administration had positive effects on hemoglobin levels (Hedge's g statistic: 0.51) and ferritin level (0.88), transferrin saturation (0.39). Besides, we also report reduced incidence of treatment related TEAEs (-0.24) for patients consuming ferumoxytol as compared conventional iron supplement formulations. CONCLUSIONS: This meta-analysis provides preliminary evidence that ferumoxytol use exerts beneficial effects on the overall hematological outcomes in patients with chronic kidney disease. This study also reports improved treatment related safety profile for ferumoxytol when compared with conventional iron formulations. The findings from this study can have direct implications in forming best practice guidelines for managing anemia in patients with chronic kidney disease.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Óxido Ferroso-Férrico/uso terapêutico , Hematínicos/uso terapêutico , Insuficiência Renal Crônica/complicações , Anemia Ferropriva/etiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Diálise Renal , Insuficiência Renal Crônica/terapia
3.
Clin Nephrol ; 95(4): 189-194, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33433318

RESUMO

BACKGROUND: Intravenous iron is one of the main therapies for anemia management in hemodialysis-dependent patients. Data comparing the efficacy of ferumoxytol versus other parenteral iron supplements are scarce. The objective of the study was to compare the efficacy of ferumoxytol with that of sodium ferric gluconate in outpatient hemodialysis patients. MATERIALS AND METHODS: A prospective, observational study was conducted in outpatients receiving ferumoxytol 510 mg once or twice quarterly compared to sodium ferric gluconate 125 mg weekly in a single center hemodialysis center in Ontario, Canada. Patient demographics, hemoglobin levels, iron indices, iron doses, and erythropoiesis-stimulating agent (ESA) doses were collected. RESULTS: The study sample consisted of 291 observations from 173 patients. Generalized estimating equations of multiple linear regression modeling were conducted to compare the outcomes while adjusting for baseline scores. Approximately 25% of the study participants received ferumoxytol while 75% received sodium ferric gluconate. Patients treated were mainly males (58.4%), and the mean age was 68.73 (SD ± 13.03) years. Both groups did not show significant differences in their hemoglobin levels (Wald z = 0.54; p = 0.46), ESA utilization at 3 months (Wald z = 0.20; p = 0.65), and TSAT levels (Wald z = 3.45; p = 0.06). However, the iron levels (Wald z = 4.24; p = 0.04) and ferritin levels (Wald z = 5.14; p = 0.02) were higher in the ferric gluconate group (Wald z = 58.78; p ≤ 0.001), and patients who received ferumoxytol received more blood transfusions as compared to those who received sodium ferric gluconate (χ2 = 16.71; p ≤ 0.001). CONCLUSION: Both iron products maintained hemoglobin levels, but patients receiving ferumoxytol had lower iron indices and received more blood transfusions compared to patients who received sodium ferric gluconate.


Assuntos
Anemia , Compostos Férricos , Óxido Ferroso-Férrico , Diálise Renal/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Anemia/tratamento farmacológico , Anemia/etiologia , Transfusão de Sangue/estatística & dados numéricos , Feminino , Compostos Férricos/administração & dosagem , Compostos Férricos/uso terapêutico , Óxido Ferroso-Férrico/administração & dosagem , Óxido Ferroso-Férrico/uso terapêutico , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
4.
Nat Commun ; 11(1): 4446, 2020 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-32895387

RESUMO

Owing to the poor penetration depth of light, phototherapy, including photothermal and photodynamic therapies, remains severely ineffective in treating deep tissue infections such as methicillin-resistant Staphylococcus aureus (MRSA)-infected osteomyelitis. Here, we report a microwave-excited antibacterial nanocapturer system for treating deep tissue infections that consists of microwave-responsive Fe3O4/CNT and the chemotherapy agent gentamicin (Gent). This system, Fe3O4/CNT/Gent, is proven to efficiently target and eradicate MRSA-infected rabbit tibia osteomyelitis. Its robust antibacterial effectiveness is attributed to the precise bacteria-capturing ability and magnetic targeting of the nanocapturer, as well as the subsequent synergistic effects of precise microwaveocaloric therapy from Fe3O4/CNT and chemotherapy from the effective release of antibiotics in infection sites. The advanced target-nanocapturer of microwave-excited microwaveocaloric-chemotherapy with effective targeting developed in this study makes a major step forward in microwave therapy for deep tissue infections.


Assuntos
Nanopartículas de Magnetita/uso terapêutico , Micro-Ondas/uso terapêutico , Osteomielite/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/uso terapêutico , Sistemas de Liberação de Medicamentos/métodos , Tratamento Farmacológico/métodos , Óxido Ferroso-Férrico/uso terapêutico , Gentamicinas/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nanotubos de Carbono , Osteomielite/microbiologia , Coelhos
5.
ACS Appl Mater Interfaces ; 12(17): 19285-19294, 2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32249558

RESUMO

Magnetite (Fe3O4) nanoparticles have been extensively used in noninvasive cancer treatment, for example, magnetic hyperthermia (MH) and chemodynamic therapy (CDT). However, how to achieve a highly efficient MH-CDT synergistic therapy based only on a single component of Fe3O4 still remains a challenge. Herein, hollow Fe3O4 mesocrystals (MCs) are constructed via a modified solvothermal method. Owing to the distinctive magnetic property of the mesocrystalline structure, Fe3O4 MCs show excellent magnetothermal conversion efficiency with a specific absorption rate of 722 w g-1 at a Fe concentration of 0.6 mg mL-1, much higher than that of Fe3O4 polycrystals (PCs). Moreover, Fe3O4 MCs also exhibit higher peroxidase-like activity than Fe3O4 PCs, which may be ascribed to the higher ratio of Fe2+/Fe3+ and more oxygen defects in the Fe3O4 MCs. Detailed in vivo results confirm that Fe3O4 MCs can instantly initiate CDT by producing the detrimental •OH, and such boosted reactive oxygen levels not only induces cell apoptosis but also reduces the expression of heat shock proteins, thus enabling low-temperature-mediated MH. More importantly, the in situ rising temperature resulted from MH in turn facilitates CDT, thus achieving a self-augmented synergistic effect between MH and CDT.


Assuntos
Antineoplásicos/uso terapêutico , Óxido Ferroso-Férrico/uso terapêutico , Hipertermia Induzida/métodos , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Catálise , Feminino , Óxido Ferroso-Férrico/química , Radical Hidroxila/metabolismo , Fenômenos Magnéticos , Camundongos Endogâmicos BALB C , Neoplasias/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Sci Rep ; 10(1): 1171, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980695

RESUMO

The use of magnetic fluid hyperthermia (MFH) for cancer therapy has shown promise but lacks suitable methods for quantifying exogenous irons such as superparamagnetic iron oxide (SPIO) nanoparticles as a source of heat generation under an alternating magnetic field (AMF). Application of quantitative susceptibility mapping (QSM) technique to prediction of SPIO in preclinical models has been challenging due to a large variation of susceptibility values, chemical shift from tissue fat, and noisier data arising from the higher resolution required to visualize the anatomy of small animals. In this study, we developed a robust QSM for the SPIO ferumoxytol in live mice to examine its potential application in MFH for cancer therapy. We demonstrated that QSM was able to simultaneously detect high level ferumoxytol accumulation in the liver and low level localization near the periphery of tumors. Detection of ferumoxytol distribution in the body by QSM, however, required imaging prior to and post ferumoxytol injection to discriminate exogenous iron susceptibility from other endogenous sources. Intratumoral injection of ferumoxytol combined with AMF produced a ferumoxytol-dose dependent tumor killing. Histology of tumor sections corroborated QSM visualization of ferumoxytol distribution near the tumor periphery, and confirmed the spatial correlation of cell death with ferumoxytol distribution. Due to the dissipation of SPIOs from the injection site, quantitative mapping of SPIO distribution will aid in estimating a change in temperature in tissues, thereby maximizing MFH effects on tumors and minimizing side-effects by avoiding unwanted tissue heating.


Assuntos
Compostos Férricos/análise , Óxido Ferroso-Férrico/análise , Hipertermia Induzida , Nanopartículas/análise , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Animais , Linhagem Celular Tumoral , Meios de Contraste , Compostos Férricos/farmacocinética , Compostos Férricos/uso terapêutico , Óxido Ferroso-Férrico/farmacocinética , Óxido Ferroso-Férrico/uso terapêutico , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos NOD , Nanopartículas/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata/patologia , Radioisótopos , Compostos Radiofarmacêuticos , Tela Subcutânea , Distribuição Tecidual , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Zircônio
7.
Radiology ; 290(1): 198-206, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30398435

RESUMO

Purpose To investigate ferumoxytol-enhanced MRI as a noninvasive imaging biomarker of macrophages in adults with high-grade gliomas. Materials and Methods In this prospective study, adults with high-grade gliomas were enrolled between July 2015 and July 2017. Each participant was administered intravenous ferumoxytol (5 mg/kg) and underwent 3.0-T MRI 24 hours later. Two sites in each tumor were selected for intraoperative sampling on the basis of the degree of ferumoxytol-induced signal change. Susceptibility and the relaxation rates R2* (1/T2*) and R2 (1/T2) were obtained by region-of-interest analysis by using the respective postprocessed maps. Each sample was stained with Prussian blue, CD68, CD163, and glial fibrillary acidic protein. Pearson correlation and linear mixed models were performed to assess the relationship between imaging measurements and number of 400× magnification high-power fields with iron-containing macrophages. Results Ten adults (four male participants [mean age, 65 years ± 9 {standard deviation}; age range, 57-74 years] and six female participants [mean age, 53 years ± 12 years; age range, 32-65 years]; mean age of all participants, 58 years ± 12 [age range, 32-74 years]) with high-grade gliomas were included. Significant positive correlations were found between susceptibility, R2*, and R2' and the number of high-power fields with CD163-positive (r range, 0.64-0.71; P < .01) and CD68-positive (r range, 0.55-0.57; P value range, .01-.02) iron-containing macrophages. No significant correlation was found between R2 and CD163-positive (r = 0.33; P = .16) and CD68-positive (r = 0.24; P = .32) iron-containing macrophages. Similar significance results were obtained with linear mixed models. At histopathologic analysis, iron particles were found only in macrophages; none was found in glial fibrillary acidic protein-positive tumor cells. Conclusion MRI measurements of susceptibility, R2*, and R2' (R2* - R2) obtained after ferumoxytol administration correlate with iron-containing macrophage concentration, and this shows their potential as quantitative imaging markers of macrophages in malignant gliomas. © RSNA, 2018 Online supplemental material is available for this article.


Assuntos
Neoplasias Encefálicas , Óxido Ferroso-Férrico/uso terapêutico , Glioma , Macrófagos/citologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Feminino , Glioma/diagnóstico por imagem , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos
8.
Expert Rev Hematol ; 11(10): 829-834, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30188740

RESUMO

INTRODUCTION: Ferumoxytol is a superparamagnetic molecule originally developed as a contrast agent for magnetic resonance imaging. Elemental iron is contained within the carbohydrate core and is released slowly after infusion allowing a large dose of iron to be administered in a short period of time. Ferumoxytol, originally approved for iron deficiency in chronic kidney disease, received a broad label for any cause of iron deficiency after oral iron intolerance or in those circumstances when oral iron is ineffective or harmful. Areas covered: The chemistry, pharmacology and pharmacokinetics of ferumoxytol were reviewed. Retrospective, observational, and prospective phase II and III trials were reviewed. When appropriate, comparative safety and efficacy parameters were reported. Differentiation between minor infusion reactions and more severe hypersensitivity reactions that may lead to anaphylaxis is described. Expert commentary: Ferumoxytol is a safe and effective iron formulation providing a means of iron repletion in persons with iron deficiency with or without anemia. Relative to iron sucrose, ferric gluconate, and iron dextran and similar to ferric carboxymaltose and iron isomaltoside, ferumoxytol yields relatively low quantities of labile free iron. Hypersensitivity and anaphylaxis is extremely rare. Hypophosphatemia with ferumoxytol's administration is extremely rare. Optimal strategies for application of ferumoxytol-enhanced imaging and full replacement dosing in a single setting remain to be determined.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Óxido Ferroso-Férrico/uso terapêutico , Anafilaxia/induzido quimicamente , Anafilaxia/epidemiologia , Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Meios de Contraste/efeitos adversos , Meios de Contraste/uso terapêutico , Hipersensibilidade a Drogas/epidemiologia , Feminino , Óxido Ferroso-Férrico/efeitos adversos , Humanos , Masculino , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/epidemiologia
9.
J Colloid Interface Sci ; 530: 547-555, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30005231

RESUMO

Multifunctional nanocomposites for image-guided cancer therapy are highly desired in clinical application. Herein, a novel theranostic agent based on gold and ferroferric oxide nanoparticles coating polypyrrole particles (PPy@Fe3O4/Au nanocomposites) for computed tomography (CT) and magnetic resonance (MR) imaging guided photothermal therapy was successfully assembled by a very facile electrostatic adsorption method. PPy@Fe3O4/Au nanocomposites exhibit good biocompatibility in vitro and in vivo. Because of high r2 relaxivity of Fe3O4 and high X-ray attenuation ability of Au, the PPy@Fe3O4/Au nanocomposites exhibited desirable CT and MR imaging performance, which provide more comprehensive and accurate diagnostic information. Moreover, PPy@Fe3O4/Au nanocomposites can efficiently kill cancer cells by hyperthermia with the guiding of CT and MR imaging, even completely ablate tumours. Hence, the electrostatic adsorption assembled PPy@Fe3O4/Au nanocomposites have great potential in clinical application for diagnosing and treating tumour in the future.


Assuntos
Óxido Ferroso-Férrico/uso terapêutico , Ouro/uso terapêutico , Nanocompostos/uso terapêutico , Neoplasias/diagnóstico , Neoplasias/terapia , Polímeros/uso terapêutico , Pirróis/uso terapêutico , Animais , Meios de Contraste/química , Meios de Contraste/uso terapêutico , Óxido Ferroso-Férrico/química , Ouro/química , Células HeLa , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipertermia Induzida/métodos , Imageamento por Ressonância Magnética/métodos , Camundongos SCID , Nanocompostos/química , Nanocompostos/ultraestrutura , Fototerapia/métodos , Polímeros/química , Pirróis/química , Nanomedicina Teranóstica/métodos , Tomografia Computadorizada por Raios X/métodos
10.
Bioconjug Chem ; 29(2): 559-570, 2018 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-29376319

RESUMO

Liver cancer is currently among the most challenging cancers to diagnose and treat. It is of prime importance to minimize the side effects on healthy tissues and reduce drug resistance for precise diagnoses and effective treatment of liver cancer. Herein, we report a facile but high-yield approach to fabricate a multifunctional nanomaterial through the loading of chitosan and metformin on Mn-doped Fe3O4@MoS2 nanoflowers. Mn-doped Fe3O4 cores are used as simultaneous T1/T2 magnetic resonance imaging (MRI) agents for sensitive and accurate cancer diagnosis, while MoS2 nanosheets are used as effective near-infrared photothermal conversion agents for potential photothermal therapy. The surface-functionalized chitosan was able not only to improve the dispersibility of Mn-doped Fe3O4@MoS2 nanoflowers in biofluids and increase their biocompatibility, but also to significantly enhance the photothermal effect. Furthermore, metformin loading led to high suppression and eradication of hepatoma cells when photothermally sensitized, but exhibited negligible effects on normal liver cells. Due to its excellent combination of T1/T2 MRI properties with sensitive chemotherapeutic and photothermal effects, our study highlights the promise of developing multifunctional nanomaterials for accurate multimodal imaging-guided, and highly sensitive therapy of liver cancer.


Assuntos
Dissulfetos/química , Óxido Ferroso-Férrico/química , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Manganês/química , Molibdênio/química , Nanoestruturas/química , Linhagem Celular Tumoral , Quitosana/química , Quitosana/uso terapêutico , Dissulfetos/uso terapêutico , Óxido Ferroso-Férrico/uso terapêutico , Humanos , Hipertermia Induzida/métodos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Manganês/uso terapêutico , Metformina/administração & dosagem , Metformina/uso terapêutico , Molibdênio/uso terapêutico , Imagem Multimodal/métodos , Nanoestruturas/uso terapêutico , Fototerapia/métodos
11.
J Biomater Sci Polym Ed ; 29(2): 181-194, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29165044

RESUMO

To find a promising drug carrier to suppress tumor using magnetic induction hyperthermia (MIH) and targeted therapy, two superparamagnetic iron oxide nanoparticles (SPIONs) coated with polyethylene glycol (PEG) and LyP-1, respectively, were prepared and compared. The particle size ranges of PEG-SPIONs and LyP-1-SPIONs were 10-15 nm, and 15-20 nm, respectively. In FTIR spectra, PEG-SPIONs and LyP-1-SPIONs had strong peaks between 575 and 1630 cm-1. Specifically, the PEG-SPIONs mainly has peaks in 581 and 1630 cm-1. The LyP-1-SPIONs mainly had peaks in 575, 1050 and 1625 cm-1. The contents of Fe3O4 in the PEG-SPIONs and LyP-1-SPIONs were about 94.24 and 89.26%, respectively. The iron contents in the MCF-7 and CT-26 cells were 33.1 ± 1.8 and 27.9 ± 0.95 pg, respectively, after co-incubation with LyP-1-SPIONs for 8 h. The LyP-1-SPIONs accumulated in the nucleus of MCF-7 cells while PEG-SPIONs in cytoplasma. In vitro, after 30 days we can found the tumor almost stopped to grow in Group LyP-1-SPIONs. LyP-1-SPIONs are promising in treating cancer as they accumulated in the nucleus of MCF-7 cells which expressed p32 and almost stopped tumor growth by combined MIH and targeted therapy.


Assuntos
Proliferação de Células/efeitos dos fármacos , Óxido Ferroso-Férrico/farmacologia , Hipertermia Induzida/métodos , Neoplasias/patologia , Peptídeos Cíclicos/farmacologia , Animais , Linhagem Celular Tumoral , Feminino , Compostos Férricos/química , Compostos Férricos/farmacologia , Óxido Ferroso-Férrico/química , Óxido Ferroso-Férrico/uso terapêutico , Humanos , Células MCF-7 , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/terapia , Peptídeos Cíclicos/química , Peptídeos Cíclicos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Radiology ; 286(1): 326-337, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29040038

RESUMO

Purpose To assess the technical feasibility of the use of ferumoxytol-enhanced (FE) magnetic resonance (MR) angiography for vascular mapping before transcatheter aortic valve replacement in patients with renal impairment. Materials and Methods This was an institutional review board-approved and HIPAA-compliant study. FE MR angiography was performed at 3.0 T or 1.5 T. Unenhanced computed tomographic (CT) images were used to overlay vascular calcification on FE MR angiographic images as composite fused three-dimensional data. Image quality of the subclavian and aortoiliofemoral arterial tree and confidence in the assessment of calcification were evaluated by using a four-point scale (4 = excellent vascular definition or strong confidence). Signal intensity nonuniformity as reflected by the heterogeneity index (ratio between the mean standard deviation of luminal signal intensity and the mean luminal signal intensity), signal-to-noise ratio, and consistency of luminal diameter measurements were quantified. Findings at FE MR angiography were compared with pelvic angiograms. Results Twenty-six patients underwent FE MR angiography without adverse events. A total of 286 named vascular segments were scored. The image quality score was 4 for 99% (283 of 286) of the segments (κ = 0.9). There was moderate to strong confidence in the ability to assess vascular calcific morphology in all studies with complementary unenhanced CT. The steady-state luminal heterogeneity index was low, and signal-to-noise ratio was high. Interobserver luminal measurements were reliable (intraclass correlation coefficient, 0.98; 95% confidence interval: 0.98, 0.99). FE MR angiographic findings were consistent with correlative pelvic angiograms in all 16 patients for whom the latter were available. Conclusion In patients with renal impairment undergoing transcatheter aortic valve replacement, FE MR angiography is technically feasible and offers reliable vascular mapping without exposure to iodine- or gadolinium-based contrast agents. Thus, the total cumulative dose of iodine-based contrast material is minimized and the risk of acute nephropathy is reduced. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Óxido Ferroso-Férrico/uso terapêutico , Nefropatias/complicações , Angiografia por Ressonância Magnética/métodos , Medicina de Precisão/métodos , Substituição da Valva Aórtica Transcateter/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Doenças das Valvas Cardíacas/complicações , Doenças das Valvas Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
13.
Biomaterials ; 141: 210-222, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28689117

RESUMO

Magnetic hyperthermia was reported to increase the survival of patients with recurrent glioblastoma by 7 months. This promising result may potentially be further improved by using iron oxide nanoparticles, called magnetosomes, which are synthesized by magnetotactic bacteria, extracted from these bacteria, purified to remove most endotoxins and organic material, and then coated with poly-l-lysine to yield a stable and non-pyrogenic nanoparticle suspension. Due to their ferrimagnetic behavior, high crystallinity and chain arrangement, these magnetosomes coated with poly-l-lysine (M-PLL) are characterized by a higher heating power than their chemically synthesized counterparts currently used in clinical trials. M-PLL-enhanced antitumor efficacy was demonstrated by administering 500-700 µg in iron of M-PLL to intracranial U87-Luc tumors of 1.5 mm3 and by exposing mice to 27 magnetic sessions each lasting 30 min, during which an alternating magnetic field of 202 kHz and 27 mT was applied. Treatment conditions were adjusted to reach a typical hyperthermia temperature of 42 °C during the first magnetic session. In 100% of treated mice, bioluminescence due to living glioblastoma cells fully disappeared 68 days following tumor cell implantation (D68). These mice were all still alive at D350. Histological analysis of their brain tissues revealed an absence of tumor cells, suggesting that they were fully cured. In comparison, antitumor efficacy was less pronounced in mice treated by the administration of IONP followed by 23 magnetic sessions, leading to full tumor bioluminescence disappearance in only 20% of the treated mice.


Assuntos
Neoplasias Encefálicas/terapia , Materiais Revestidos Biocompatíveis/uso terapêutico , Óxido Ferroso-Férrico/uso terapêutico , Glioblastoma/terapia , Hipertermia Induzida/métodos , Magnetossomos/química , Polilisina/uso terapêutico , Células 3T3 , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Materiais Revestidos Biocompatíveis/química , Feminino , Óxido Ferroso-Férrico/química , Glioblastoma/patologia , Humanos , Campos Magnéticos , Magnetossomos/ultraestrutura , Magnetospirillum/química , Camundongos , Camundongos Nus , Polilisina/análogos & derivados
14.
BMC Nephrol ; 18(1): 117, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28372549

RESUMO

BACKGROUND: Iron deficiency anemia (IDA) is a common manifestation of chronic kidney disease (CKD), affecting most patients on hemodialysis and imposing a substantial clinical burden. Treatment with iron supplementation increases hemoglobin levels and can reduce the severity of anemia in patients with CKD. While correcting anemia in these patients is an important therapeutic goal, there is a lack of long-term trials directly comparing intravenous iron therapies in patients with CKD receiving hemodialysis. METHODS/DESIGN: The Ferumoxytol for Anemia of CKD Trial (FACT) is a 13-month, open-label, randomized, multicenter, international, prospective study with 2 substudies. Entry criteria for the main study include adults with IDA (defined as hemoglobin <11.5 g/dL [<115.0 g/L] and a transferrin saturation <30%), serum ferritin <800 ng/mL (<1798 pmol/L), and receiving hemodialysis for ≥3 months. Patients are randomized to receive ferumoxytol (1.02 g over 2 doses) or iron sucrose (1.0 g over 10 doses) during the initial 5-week treatment period. Those with persistent/recurrent IDA over the 11-month observation period will receive additional 5-week treatment periods, as appropriate. The primary efficacy endpoint of the main study is the mean change in hemoglobin from Baseline to Week 5 for each treatment period. The secondary efficacy endpoints include the mean change in transferrin saturation from Baseline to Week 5 and the proportion of patients with a hemoglobin increase of ≥1.0 g/dL at any time from Baseline to Week 5. Safety will be assessed through an examination of the adverse event profile over the course of the study. An "oxidative stress" substudy in approximately 100 patients will assess the effects of treatment on biomarkers of oxidative stress/inflammation during the initial 5-week treatment period, and a magnetic resonance imaging substudy in approximately 70 patients will assess the potential for iron deposition in target tissues over 24 months. DISCUSSION: FACT fulfills the need for a long-term comparative trial in patients with IDA and CKD receiving hemodialysis. The efficacy and safety results will provide useful information for guiding therapy in this population. Two hundred ninety-six patients have been enrolled, and completion of the main study is expected soon. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01227616 (registered October 22, 2010); EudraCT number: 2010-022133-28.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Compostos Férricos/uso terapêutico , Óxido Ferroso-Férrico/uso terapêutico , Ácido Glucárico/uso terapêutico , Hematínicos/uso terapêutico , Falência Renal Crônica/terapia , Diálise Renal , Administração Intravenosa , Anemia Ferropriva/etiologia , Óxido de Ferro Sacarado , Coração/diagnóstico por imagem , Humanos , Falência Renal Crônica/complicações , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Pâncreas/diagnóstico por imagem
15.
Dalton Trans ; 44(33): 14686-96, 2015 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-26215789

RESUMO

Magnetic luminescent hybrid nanostructures (MLHN) have received a great deal of attention due to their potential biomedical applications such as thermal therapy, magnetic resonance imaging, drug delivery and intracellular imaging. We report the development of bifunctional Fe3O4 decorated YPO4:Eu hybrid nanostructures by covalent bridging of carboxyl PEGylated Fe3O4 and amine functionalized YPO4:Eu particles. The surface functionalization of individual nanoparticulates as well as their successful conjugation was evident from Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), zeta-potential and transmission electron microscopy (TEM) studies. X-ray diffraction (XRD) analysis reveals the formation of highly crystalline hybrid nanostructures. TEM micrographs clearly show the binding/anchoring of 10 nm Fe3O4 nanoparticles onto the surface of 100-150 nm rice grain shaped YPO4:Eu nanostructures. These MLHN show good colloidal stability, magnetic field responsivity and self-heating capacity under an external AC magnetic field. The induction heating studies confirmed localized heating of MLHN under an AC magnetic field with a high specific absorption rate. Photoluminescence spectroscopy and fluorescence microscopy results show optical imaging capability of MLHN. Furthermore, successful internalization of these MLHN in the cells and their cellular imaging ability are confirmed from confocal microscopy imaging. Specifically, the hybrid nanostructure provides an excellent platform to integrate luminescent and magnetic materials into one single entity that can be used as a potential tool for hyperthermia treatment of cancer and cellular imaging.


Assuntos
Európio/química , Óxido Ferroso-Férrico/química , Substâncias Luminescentes/química , Nanoestruturas/química , Fosfatos/química , Ítrio/química , Linhagem Celular Tumoral , Európio/uso terapêutico , Óxido Ferroso-Férrico/uso terapêutico , Humanos , Hipertermia Induzida , Substâncias Luminescentes/uso terapêutico , Campos Magnéticos , Magnetismo , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Nanoestruturas/uso terapêutico , Nanoestruturas/ultraestrutura , Neoplasias/diagnóstico , Neoplasias/terapia , Imagem Óptica , Ítrio/uso terapêutico
16.
Dtsch Med Wochenschr ; 138(24): 1312-7, 2013 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-23737117

RESUMO

Iron deficiency often occurs in patients with chronic kidney disease and can be effectively treated with parenteral supplementation of iron. In these patients, prompt application of iron therapy can help to reduce the dependence of erythropoietin-stimulating agents and effectively treat anemia. Correct evaluation of iron metabolism in CKD patients can be difficult. Duration of and response to therapy should always be considered while planning parenteral supplementation of iron. The main safety aspects of parenteral iron preparations relate to their possible anaphylactic potential and the potential induction of oxidative stress due to the release of free iron. However, parenteral iron supplementation is usually safe and without major side effects. Regarding current data, none of the iron preparations is showing definitive superiority. Although uncommon, iron preparations containing dextran can lead to severe side effects, therefore these preparations appear to have an inferior safety profile. Due to limited data, a comparison of third-generation iron preparations with previous preparations is not possible. Recently, for the first time, the third generation iron preparation ferumoxytol has been directly compared to iron sucrose. From this data and others, it remains unclear whether third generation iron preparations show safety-relevant superiority.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Compostos de Ferro/administração & dosagem , Compostos de Ferro/efeitos adversos , Falência Renal Crônica/complicações , Administração Oral , Anafilaxia/induzido quimicamente , Dissacarídeos/efeitos adversos , Dissacarídeos/uso terapêutico , Compostos Férricos/efeitos adversos , Compostos Férricos/uso terapêutico , Óxido de Ferro Sacarado , Óxido Ferroso-Férrico/efeitos adversos , Óxido Ferroso-Férrico/uso terapêutico , Ácido Glucárico/efeitos adversos , Ácido Glucárico/uso terapêutico , Humanos , Infusões Intravenosas , Complexo Ferro-Dextran/efeitos adversos , Complexo Ferro-Dextran/uso terapêutico , Falência Renal Crônica/terapia , Maltose/efeitos adversos , Maltose/análogos & derivados , Maltose/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Diálise Renal
17.
Biomaterials ; 34(16): 4078-4088, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23465836

RESUMO

The photothermal effect of Fe3O4 magnetic nanoparticles is investigated for cancer therapy both in vitro and in vivo experiments. Heat is found to be rapidly generated by red and near-infrared (NIR) range laser irradiation of Fe3O4 nanoparticles with spherical, hexagonal and wire-like shapes. These Fe3O4 nanoparticles are coated with carboxyl-terminated poly (ethylene glycol)-phospholipid for enhanced dispersion in water. The surface-functionalized Fe3O4 nanoparticles can be taken up by esophageal cancer cells and do not obviously affect the cell structure and viability. Upon irradiation at 808 nm however, the esophageal cancer cell viability is effectively suppressed, and the cellular organelles are obviously damaged when incubated with the NIR laser activated Fe3O4 nanoparticles. Mouse esophageal tumor growth was found to be significantly inhibited by the photothermal effect of Fe3O4 nanoparticles, resulting in effective tumor reduction. A morphological examination revealed that after a photothermal therapy, the tumor tissue structure exhibited discontinuation, the cells were significantly shriveled and some cells have finally disintegrated.


Assuntos
Óxido Ferroso-Férrico/uso terapêutico , Raios Infravermelhos , Lasers , Nanopartículas de Magnetita/uso terapêutico , Neoplasias/terapia , Fototerapia/métodos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Humanos , Nanopartículas de Magnetita/ultraestrutura , Camundongos , Camundongos Nus , Neoplasias/patologia , Espectrometria por Raios X , Espectrofotometria Atômica , Temperatura , Fatores de Tempo , Carga Tumoral/efeitos da radiação
18.
Nanotechnology ; 24(6): 065101, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23324398

RESUMO

Polyol mediated synthesized luminescent YVO(4):Eu(3+) nanoparticles (NPs) have been encapsulated in mesoporous silica nanoparticles (MSNs) using the sol-gel process. X-ray diffraction and Fourier transform infrared spectroscopy along with transmission electron microscopy confirm the encapsulation of the YVO(4):Eu(3+) NPs in the SiO(2) matrix. N(2) adsorption/desorption analysis confirms the mesoporous nature of the MSNs and YVO(4):Eu(3+)-MSNs. No significant quenching of the YVO(4):Eu(3+) luminescence is observed for YVO(4):Eu(3+)-MSNs. This nanocomposite has been tested as a potential drug carrier. Efficient loading of doxorubicin hydrochloride (DOX), a typical anticancer drug, is observed which reaches up to 93% in 8 mg ml(-1) of YVO(4):Eu(3+)-MSNs. pH sensitive release of DOX is observed, with 54% release for pH 4.3 and 31% in a physiological environment (pH 7.4). Both MSNs and YVO(4):Eu(3+)-MSNs nanocomposites do not show accountable toxicity to two cell lines, i.e. HeLa and MCF-7. However, as desired, toxicity is observed when cells are incubated with DOX loaded YVO(4):Eu(3+)-MSNs. Laser scanning confocal microscopy images confirm the uptake of the nanocomposite in both cell lines. The morphology of the cells (MCF-7) changes after incubation with DOX loaded YVO(4):Eu(3+)-MSNs, indicating an interaction of DOX with the cells. More cytotoxicity to both cell lines with ∼90% killing is observed due to the synergistic effect of magnetic fluid hyperthermia and chemotherapy using a biphasic suspension of superparamagnetic iron oxide magnetic nanoparticles and DOX loaded YVO(4):Eu(3+)-MSNs. In addition, an AC magnetic field triggers an enhanced drug release.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Nanopartículas/uso terapêutico , Neoplasias/diagnóstico , Neoplasias/terapia , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/uso terapêutico , Portadores de Fármacos/toxicidade , Európio/química , Európio/uso terapêutico , Európio/toxicidade , Óxido Ferroso-Férrico/química , Óxido Ferroso-Férrico/uso terapêutico , Óxido Ferroso-Férrico/toxicidade , Humanos , Hipertermia Induzida/métodos , Magnetismo/métodos , Nanopartículas/química , Nanopartículas/toxicidade , Dióxido de Silício/química , Dióxido de Silício/uso terapêutico , Dióxido de Silício/toxicidade , Vanadatos/química , Vanadatos/uso terapêutico , Vanadatos/toxicidade , Ítrio/química , Ítrio/uso terapêutico , Ítrio/toxicidade
19.
Expert Rev Hematol ; 4(4): 399-406, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21801130

RESUMO

Intravenous iron is standard for dialysis-associated anemia and its use is rising dramatically in other settings. Except for the dextrans, full iron replacement requires multiple visits. Nonetheless, safety concerns abound. Ferumoxytol, a recently approved modified dextran with a carbohydrate core that tightly binds the iron moiety, decreasing free iron and ostensibly increasing safety, was approved by the US FDA, in June 2009, for the treatment of iron deficiency associated with chronic kidney disease and end-stage renal disease. This formulation, uniquely, can be administered in a large dose as a short intravenous injection of 1 min or less, markedly facilitating care. Recent post-marketing safety issues have been raised resulting in a change in the package insert. This article examines existing clinical data and posits reasons for the labeling change. Potential future use of this formulation is opined.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Óxido Ferroso-Férrico/uso terapêutico , Anemia Ferropriva/metabolismo , Feminino , Óxido Ferroso-Férrico/farmacocinética , Hematínicos/farmacocinética , Hematínicos/uso terapêutico , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Insuficiência Renal Crônica/metabolismo
20.
J Am Chem Soc ; 132(21): 7234-7, 2010 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-20459132

RESUMO

Compact nanostructures with highly integrated functionalities are of considerable current interest to drug delivery, multimodality imaging, and electronic devices. A key challenge, however, is how to combine individual components together without interfering or sacrificing their original electronic and optical properties. Here, we demonstrate a new class of nanocomposites with spatially separated functionalities. We further demonstrate magnetic field modulated imaging and an innovative application of this technology in cancer cell treatment, magnetolytic therapy, based on magnetically controlled mechanical damage to cell membranes.


Assuntos
Óxido Ferroso-Férrico/química , Magnetoterapia/métodos , Microscopia Eletrônica de Transmissão/métodos , Nanocompostos/química , Compostos Férricos , Óxido Ferroso-Férrico/uso terapêutico , Humanos , Nanocompostos/uso terapêutico
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