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1.
Life Sci ; 281: 119799, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34229007

RESUMEN

Despite numerous studies on the mechanisms of cigarette smoking toxicity over the past three decades, some aspects remain obscure. Recent developments have drawn attention to some hopeful indicators that allow us to advance our awareness of cigarette-induced cell death. Ferroptosis is considered a type of governed death of cells distinguished by the iron-dependent lipid hydroperoxide deposition to fatal concentrations. Ferroptosis has been linked with pathological settings such as neurodegenerative diseases, cancer, heart attack, hemorrhagic stroke, traumatic brain injury, ischemia-reperfusion injury, and renal dysfunction. This review tries to explain the causal role of ferroptosis cascade in cigarette smoke-mediated toxicity and cell death, highlighting associations on potential action mechanisms and proposing suggestions for its detoxifying and therapeutic interventions.


Asunto(s)
Ferroptosis , Hierro/metabolismo , Humo/efectos adversos , Productos de Tabaco , Humanos
2.
Mol Pharm ; 18(8): 3171-3180, 2021 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-34279974

RESUMEN

Current treatment of chronic wounds has been critically limited by various factors, including bacterial infection, biofilm formation, impaired angiogenesis, and prolonged inflammation. Addressing these challenges, we developed a multifunctional wound dressing-based three-pronged approach for accelerating wound healing. The multifunctional wound dressing, composed of nanofibers, functional nanoparticles, natural biopolymers, and selected protein and peptide, can target multiple endogenous repair mechanisms and represents a promising alternative to current wound healing products.


Asunto(s)
Anexina A1/administración & dosificación , Antiinflamatorios/administración & dosificación , Vendajes , Diabetes Mellitus Experimental/complicaciones , Proteínas Relacionadas con la Folistatina/administración & dosificación , Péptidos/administración & dosificación , Infecciones Estafilocócicas/complicaciones , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Herida Quirúrgica/complicaciones , Herida Quirúrgica/tratamiento farmacológico , Cicatrización de Heridas/efectos de los fármacos , Infección de Heridas/complicaciones , Infección de Heridas/tratamiento farmacológico , Células 3T3 , Animales , Materiales Biocompatibles/administración & dosificación , Biopolímeros/química , Supervivencia Celular/efectos de los fármacos , Diabetes Mellitus Experimental/inducido químicamente , Células HaCaT , Humanos , Nanopartículas Magnéticas de Óxido de Hierro/química , Masculino , Ensayo de Materiales/métodos , Ratones , Nanofibras/química , Ratas , Ratas Wistar , Infecciones Estafilocócicas/microbiología , Resultado del Tratamiento , Infección de Heridas/microbiología
3.
ACG Case Rep J ; 8(7): e00635, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34307713

RESUMEN

We present a 63-year-old man with a medical history of hepatocellular carcinoma who underwent orthotopic liver transplant 10 years prior on long-term immunosuppressive therapy. The patient presented to the clinic with diarrhea, and the workup revealed mantle cell lymphoma. Mantle cell lymphoma is an extremely rare finding in transplanted livers. It is essential to include mantle cell lymphoma, along with a broad differential, during the workup of diarrhea in post-transplant patients.

4.
Nanomedicine ; 29: 102243, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32623018

RESUMEN

Many tumors develop resistance to most of the apoptosis-based cancer therapies. In this sense targeting non-apoptotic forms of cell death including necroptosis, autophagy and ferroptosis may have therapeutic benefits in apoptosis-defective cancer cells. Nanomaterials have shown great advantages in cancer treatment owing to their unique characteristics. Besides, the capability of nanomaterials to induce different forms of cell death has gained widespread attention in cancer treatment. Reports in this field reflect the therapeutic potential of necroptotic cell death induced by nanomaterials in cancer. Also, autophagic cell death induced by nanomaterials alone and as a part of chemo-, radio- and photothermal therapy holds great promise as anticancer therapeutic option. Besides, ferroptosis induction by iron-based nanomaterials in drug delivery, immunotherapy, hyperthermia and imaging systems shows promising results in malignancies. Hence, this review is devoted to the latest efforts and the challenges in this field of research and its clinical merits.


Asunto(s)
Muerte Celular/efectos de los fármacos , Nanoestructuras/uso terapéutico , Necroptosis/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Apoptosis/genética , Autofagia/efectos de los fármacos , Autofagia/genética , Muerte Celular/genética , Ferroptosis/efectos de los fármacos , Ferroptosis/genética , Humanos , Necroptosis/genética , Neoplasias/genética , Neoplasias/patología
5.
Sci Rep ; 10(1): 9664, 2020 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-32541900

RESUMEN

Protein corona significantly affects in vivo fate of nanoparticles including biodistribution and half-life. Without manipulating the physicochemical properties of nanoparticles with considering their biointerference, attaining effective treatment protocols is impossible. For this reason, protein corona evolution and biodistribution of different chitosan (Ch)-based nanoparticles including Ch and carboxymethyl dextran (CMD)/thiolated dextran (TD) polyelectrolyte complexes (PECs) were studied using highly precious and sensitive methods such as liquid chromatography-mass/mass (LC-MS/MS) spectroscopy and positron emission tomography/computed tomography (PET/CT) scan. The importance of serum presence/absence in culture medium with different pH and corona effect on cellular uptake of PECs investigated by in vitro study. Designed PECs have low amounts of proteins in corona mostly enriched by Apolipoproteins, protein C, hemoglobin subunits, and inter-alpha- trypsin inhibitor that beside improving uptake of nanoparticles, they have low liver uptake and notable heart blood pool accumulation that confirmed the long circulation time of the nanoparticles which is favorable for delivery of nanoparticles to the site of action and achieving required therapeutic effect.


Asunto(s)
Quitosano/química , Corona de Proteínas/química , Suero/química , Cromatografía Liquida , Semivida , Humanos , Células MCF-7 , Nanopartículas , Polielectrolitos/química , Tomografía Computarizada por Tomografía de Emisión de Positrones , Espectrometría de Masas en Tándem , Distribución Tisular
6.
Am J Clin Oncol ; 43(6): 435-441, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32251119

RESUMEN

BACKGROUND: Pancreatic ductal adenocarcinoma is a largely incurable cancer. Surgical resection remains the only potential option for cure. Even in surgically resectable patients, only about 10% to 20% are long-term survivors. Emerging data suggest a role for neoadjuvant therapy to target occult micrometastatic disease. AIM: To report our institutional experience with a novel neoadjuvant chemoradiation (CRT) regimen in resectable and borderline resectable pancreatic cancer. MATERIALS AND METHODS: Patients were treated with 2 cycles of induction chemotherapy with FOLFOX and then received CRT with gemcitabine and intensity-modulated radiotherapy (IMRT). RESULTS: From April 2014 to June 2017, 24 patients were enrolled. Eighteen patients were borderline resectable and 6 patients were resectable. All patients received induction chemotherapy with FOLFOX. Thirteen patients underwent pancreatectomy after CRT with a resection rate of 62%. R0 resection achieved in 11 patients (84.6%) and 2 patients had R1 resection (15.4%). For patients who underwent resection, the median progression-free survival (PFS) was 31 months, 1-year PFS rate was 69.2% (95% confidence interval [CI], 0.48-0.99), and 2-year PFS rate was 51.9% (95% CI, 0.3-0.89). Median overall survival (OS) was 34.8 months (95% CI, 1.045 to infinity), 1-year OS rate was 91.7% (95% CI, 0.77-1.0), and 2-year OS rate was 75% (95% CI, 0.54-1.0). Median CA 19-9 at screening for patients who underwent surgery was 659 (range, 18 to 2154), which decreased to 146.9 (range, 18 to 462) after CRT before resection. CONCLUSION: Neoadjuvant therapy for borderline resectable and resectable pancreatic ductal adenocarcinoma with CRT facilitated R0 resection in 84% patients who underwent surgery.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Ductal Pancreático/terapia , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/terapia , Radioterapia de Intensidad Modulada , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Ductal Pancreático/cirugía , Quimioradioterapia , Desoxicitidina/uso terapéutico , Femenino , Fluorouracilo/uso terapéutico , Humanos , Quimioterapia de Inducción , Leucovorina/uso terapéutico , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Compuestos Organoplatinos/uso terapéutico , Neoplasias Pancreáticas/cirugía , Gemcitabina
7.
Langmuir ; 36(8): 1907-1915, 2020 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-32009415

RESUMEN

The modification of cylindrical anodic aluminum oxide (AAO) nanopores by alternating layer-by-layer (LBL) deposition of poly(sodium-4-styrene sulfonate) (PSS) and poly(allylamine hydrochloride) (PAH) was studied in situ by reflectometric interference spectroscopy (RIfS). In particular, the kinetics of polyelectrolyte deposition inside the pores with a diameter of 37 ± 3 nm and a length of 3.7 ± 0.3 µm were unraveled, and potential differences in the LBL multilayer growth compared to flat silicon substrates as well as the effect of different ionic strengths and different types of ions were investigated. RIfS measures the effective optical thicknesses, which is-for a constant pore length-proportional to the effective refractive index of the AAO sample, from which, in turn, the deposited mass of the polymer or the corresponding layer thickness can be estimated. Compared to the multilayer growth by the LBL deposition on the flat aminosilane-primed silicon wafers, which was assessed by spectroscopic ellipsometry, the thickness increment per deposited bilayer, as well as the dependence of this increment on the ionic strength (0.01-0.15) and the counterion type (Na+ vs Ca2+) inside the aminosilane-primed nanopores, was for the first bilayers to within the experimental error identical. For thicker multilayers, the pore diameter became smaller, which led to reduced thickness increments and eventually virtually completely filled the pores. The observed kinetics is consistent with the mass-transport-limited adsorption of the polyelectrolyte to the charged surface according to a Langmuir isotherm with a negligible desorption rate. In addition to fundamental insights into the buildup of polyelectrolyte multilayers inside the AAO nanopores, our results highlight the sensitivity of RIfS and its use as an analytical tool for probing processes inside the nanopores and for the development of biosensors.

8.
Soft Matter ; 16(10): 2448-2459, 2020 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-31984393

RESUMEN

Inertial microfluidics has emerged over the past decade as a powerful tool to accurately control cells and microparticles for diverse biological and medical applications. Many approaches have been proposed to date in order to increase the efficiency and accuracy of inertial microfluidic systems. However, the effects of channel cross-section and solution properties (Newtonian or non-Newtonian) have not been fully explored, primarily due to limitations in current microfabrication methods. In this study, we overcome many of these limitations using wax 3D printing technology and soft lithography through a novel workflow, which eliminates the need for the use of silicon lithography and polydimethylsiloxane (PDMS) bonding. We have shown that by adding dummy structures to reinforce the main channels, optimizing the gap between the dummy and main structures, and dissolving the support wax on a PDMS slab to minimize the additional handling steps, one can make various non-conventional microchannels. These substantially improve upon previous wax printed microfluidic devices where the working area falls into the realm of macrofluidics rather than microfluidics. Results revealed a surface roughness of 1.75 µm for the printed channels, which does not affect the performance of inertial microfluidic devices used in this study. Channels with complex cross-sections were fabricated and then analyzed to investigate the effects of viscoelasticity and superposition on the lateral migration of the particles. Finally, as a proof of concept, microcarriers were separated from human mesenchymal stem cells using an optimized channel with maximum cell-holding capacity, demonstrating the suitability of these microchannels in the bioprocessing industry.


Asunto(s)
Dimetilpolisiloxanos/química , Dispositivos Laboratorio en un Chip , Microtecnología/instrumentación , Impresión Tridimensional , Ceras/química , Línea Celular , Diseño de Equipo , Humanos , Células Madre Mesenquimatosas/citología , Técnicas Analíticas Microfluídicas/instrumentación , Microesferas
9.
Colloids Surf B Biointerfaces ; 186: 110712, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31846894

RESUMEN

Free polymer graphene aerogel nanoparticles (GA NPs) were synthesized by using reduction/aggregation of graphene oxide (GO) sheets in the presence of vitamin C (as a biocompatible reductant agent) at a low temperature (40 °C), followed by an effective sonication. Synthesis of GA NPs in doxorubicin hydrochloride (DOX)-containing solution results in the simultaneous synthesis and drug loading with higher performance (than that of the separately synthesized and loaded samples). To investigate the mechanism of loading and the capability of GA NPs in the loading of other drug structures, two groups of ionized (DOX, Amikacin sulfate and, d-glucosamine hydrochloride) and non-ionized (Paclitaxel (PTX)) drugs were examined. Furthermore, the relationship between the bipolar level of DOX solution (contributing to H-bonding of DOX and GO) and the amount of DOX loading was investigated. The DOX showed higher loading (>3 times) than PTX, as anticancer drugs. Since both DOX and PTX possess aromatic structures, the higher loading of DOX was assigned to its positive partial charge and ionized nature. Accordingly, other drugs (having positive partial charge and ionized nature, but no aromatic structure) such as Amikacin sulfate and d-glucosamine hydrochloride presented higher loading than PTX. These results indicated that although the π-π interactions induced by aromatic structures are important in drug loading, the electrostatic interaction of ionized drugs with GO (especially through H-bonding) is the dominant mechanism. DOX-loaded GANPs showed high pH-sensitive release (equivalent to the carrier weight) after 5 days, which can indicate benefits in tumor cell acidic microenvironments in-vivo.


Asunto(s)
Antineoplásicos/química , Doxorrubicina/química , Grafito/química , Nanopartículas/química , Paclitaxel/química , Amicacina/química , Liberación de Fármacos , Geles/química , Glucosamina/química , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Propiedades de Superficie
10.
J Colloid Interface Sci ; 531: 245-252, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30032011

RESUMEN

HYPOTHESIS: It is now being increasingly accepted that cells in their native tissue show different morphologies than those grown on a culture plate. Culturing cells on the conventional two-dimensional (2D) culture plates does not closely resemble the in vivo three-dimensional (3D) structure of cells which in turn seems to affect cellular function. This is one of the reasons, among many others, that nanoparticles uptake and toxicology data from 2D culture plates and in vivo environments are not correlated with one another. In this study, we offer a novel platform technology for producing more in vivo-like models of in vitro cell culture. EXPERIMENTS: The normal fibroblast cells (HU02) were cultured on "pseudo-3D" substrates, made from cell imprinting approach. The respond of the cells to a model nanoparticle (gold nanorod) were compared in 2D and "pseudo-3D" cultures modes, by cytotoxicological assays. FINDINGS: It is illustrated here that the cells' respond to the exact same type of nanoparticles is majorly dependant in their shape. The use of "pseudo-3D" substrates which could partially mimic the shape of cells in vivo is strongly proposed as a means of better predicting the efficacy of the 2D cell culture plates.


Asunto(s)
Forma de la Célula , Fibroblastos/citología , Nanopartículas/toxicidad , Transporte Biológico , Ciclo Celular , Línea Celular , Supervivencia Celular , Fibroblastos/metabolismo , Humanos , Células MCF-7 , Nanopartículas/análisis , Nanopartículas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
11.
Sci Rep ; 8(1): 6842, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29717202

RESUMEN

The objective of the present study is to conjugate L-thyroxine PEI derivative onto another PEI to compensate the amine content of the whole structure which has been utilized for the ligand conjugation. Since αvß3 integrin receptors are over-expressed on cancer cells and there is binding site for L-thyroxine on these receptors, PEI conjugation by L-thyroxine along with restoring the PEI amine content might be an efficient strategy for targeted delivery using polymeric nanoparticles. The results demonstrated the ability of the PEI conjugate in the formation of nanoparticles with the size of around 210 nm with higher buffering capacity. The conjugated PEI derivative increased the transfection efficiency in the cell lines over-expressing integrin by up to two folds higher than unmodified PEI, whereas in the cell lines lacking the integrin receptors there was no ligand conjugation-associated difference in gene transfer ability. The specificity of transfection demonstrated the delivery of plasmid DNA through integrin receptors. Also, the results of in vivo imaging of the polyplexes revealed that 99mTc-labeled PEI/plasmid DNA complexes accumulated in kidney and bladder 4 h post injection. Therefore, this PEI derivative could be considered as an efficient targeted delivery system for plasmid DNA.


Asunto(s)
Integrina alfaVbeta3/genética , Nanopartículas/química , Polietileneimina/química , Transfección/métodos , Animales , ADN/administración & dosificación , ADN/química , ADN/farmacocinética , Femenino , Vectores Genéticos/administración & dosificación , Vectores Genéticos/química , Vectores Genéticos/farmacocinética , Células Hep G2 , Humanos , Ratones , Ratones Endogámicos BALB C , Tamaño de la Partícula , Plásmidos/administración & dosificación , Plásmidos/química , Plásmidos/farmacocinética
12.
Pharmacotherapy ; 38(4): 470-475, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29457839

RESUMEN

BACKGROUND: Adenoviruses are double-stranded DNA viruses that typically cause mild self-limiting respiratory, ocular, and gastrointestinal infections. In immunocompromised patients, especially transplant recipients, the infection can be severe, with dissemination and multiorgan failure. In intestinal transplant recipients, the incidence is as high as 57%. To our knowledge, no standardized guidelines or U.S. Food and Drug Administration-approved medications exist for the treatment of adenovirus disease. AIMS: We describe two isolated intestinal transplant recipients who developed adenovirus disease (viremia with viral enteritis) that was managed with a new experimental drug, brincidofovir (an oral lipid conjugate prodrug of cidofovir), as salvage therapy. RESULTS: The first patient was a 44-year-old woman who developed adenoviral enteritis 1 month after transplantation, which resolved with ribavirin therapy. Two weeks later, the infection recurred, and brincidofovir was initiated. While receiving this therapy for 3 months, she developed severe acute rejection, which was managed with rabbit antithymocyte globulin followed by infliximab. Eventually, complete resolution of the rejection and adenoviral enteritis was achieved. At 12 months posttransplantation, the patient was healthy and tolerating enteral feeding. The second patient was a 28-year-old man who had undergone isolated intestinal transplantation 6 years before he presented with generalized weakness and an increased ostomy output; he was diagnosed with adenoviral enteritis. Maintenance immunosuppression was reduced, and brincidofovir was started. The infection resolved with a month of therapy. Six months after the infection, he was healthy and tolerating enteral feeding. CONCLUSION: This is the first publication, to our knowledge, to describe two cases in which brincidofovir was used to successfully treat adenovirus infection in intestinal transplant recipients. Thus, these cases demonstrate that brincidofovir appears to be a safe and effective option in the management of adenoviral enteritis in these patients.


Asunto(s)
Infecciones por Adenoviridae/tratamiento farmacológico , Antivirales/uso terapéutico , Citosina/análogos & derivados , Huésped Inmunocomprometido , Organofosfonatos/uso terapéutico , Receptores de Trasplantes , Adulto , Citosina/uso terapéutico , Femenino , Humanos , Masculino , Terapia Recuperativa
13.
Nanoscale ; 10(3): 1228-1233, 2018 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-29292453

RESUMEN

Protein unfolding induced by nanoparticles (NPs) can lead to exposure of cryptic epitopes that might dictate biological identity and affect NP biological fate (e.g., blood circulation time, biodistribution, and tumor accumulation). Here, we monitor the conformation of fluorescence resonance energy transfer (FRET)-labelled fibronectin (FN) on corona-coated gold NPs. We found that the labelled FN proteins, which directly accessed the gold NP surface, underwent more pronounced conformational changes than those associated with the protein corona via protein-protein interactions. FRET and liquid chromatography-mass spectrometry analyses demonstrated that NP size/concentration, pH change, and the level of surface coverage by the corona can tune the accessibility of labelled FN to the gold NP surface. Although some subsequently adsorbing proteins accessed the NP surface thanks to incomplete surface coverage and protein exchange (the Vroman effect), most outer-layer proteins could not directly bind to the NP surface, blocked by pre-adsorbed corona layers. This finding was also partially confirmed by isothermal titration calorimetry (ITC) analysis. These results suggest the proof-of-concept that outermost-layer proteins with modestly changed conformation rather than unfolded proteins at the gold NP surface effectively create the NPs' biological identity, which might have important implications on biological fates of gold NPs.


Asunto(s)
Fibronectinas/química , Nanopartículas del Metal , Corona de Proteínas , Transferencia Resonante de Energía de Fluorescencia , Oro , Humanos , Conformación Proteica , Desplegamiento Proteico
14.
J Alzheimers Dis ; 59(4): 1187-1202, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28759965

RESUMEN

It is well understood that patients with different diseases may have a variety of specific proteins (e.g., type, amount, and configuration) in their plasmas. When nanoparticles (NPs) are exposed to these plasmas, the resulting coronas may incorporate some of the disease-specific proteins. Using gold (Au) NPs with different surface properties and corona composition, we have developed a technology for the discrimination and detection of two neurodegenerative diseases, Alzheimer's disease (AD) and multiple sclerosis (MS). Applying a variety of techniques, including UV-visible spectra, colorimetric response analyses and liquid chromatography-tandem mass spectrometry, we found the corona-NP complexes, obtained from different human serums, had distinct protein composition, including some specific proteins that are known as AD and MS biomarkers. The colorimetric responses, analyzed by chemometrics and statistical methods, demonstrate promising capabilities of the technology to unambiguously identify and discriminate AD and MS. The developed colorimetric technology might enable a simple, inexpensive and rapid detection/discrimination of neurodegenerative diseases.


Asunto(s)
Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/diagnóstico , Nanopartículas del Metal/química , Esclerosis Múltiple/sangre , Esclerosis Múltiple/diagnóstico , Corona de Proteínas/metabolismo , Ácido Cítrico , Colorimetría , Cisteamina , Femenino , Oro , Humanos , Masculino , Polietilenglicoles , Sensibilidad y Especificidad , Espectrometría de Fluorescencia
15.
ACS Appl Mater Interfaces ; 8(35): 22808-18, 2016 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-27526263

RESUMEN

Surface functionalization strategies for targeting nanoparticles (NP) to specific organs, cells, or organelles, is the foundation for new applications of nanomedicine to drug delivery and biomedical imaging. Interaction of NPs with biological media leads to the formation of a biomolecular layer at the surface of NPs so-called as "protein corona". This corona layer can shield active molecules at the surface of NPs and cause mistargeting or unintended scavenging by the liver, kidney, or spleen. To overcome this corona issue, we have designed biotin-cysteine conjugated silica NPs (biotin was employed as a targeting molecule and cysteine was used as a zwitterionic ligand) to inhibit corona-induced mistargeting and thus significantly enhance the active targeting capability of NPs in complex biological media. To probe the targeting yield of our engineered NPs, we employed both modified silicon wafer substrates with streptavidin (i.e., biotin receptor) to simulate a target and a cell-based model platform using tumor cell lines that overexpress biotin receptors. In both cases, after incubation with human plasma (thus forming a protein corona), cellular uptake/substrate attachment of the targeted NPs with zwitterionic coatings were significantly higher than the same NPs without zwitterionic coating. Our results demonstrated that NPs with a zwitterionic surface can considerably facilitate targeting yield of NPs and provide a promising new type of nanocarriers in biological applications.


Asunto(s)
Corona de Proteínas/química , Sistemas de Liberación de Medicamentos , Humanos , Nanomedicina , Nanopartículas , Dióxido de Silicio
16.
Nanomedicine ; 12(2): 287-307, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26707817

RESUMEN

Nanomedicine, the integration of nanotechnological tools in medicine demonstrated promising potential to revolutionize the diagnosis and treatment of various human health conditions. Nanoparticles (NPs) have shown much promise in diagnostics of cancer, especially since they can accommodate targeting molecules on their surface, which search for specific tumor cell receptors upon injection into the blood stream. This concentrates the NPs in the desired tumor location. Furthermore, such receptor-specific targeting may be exploited for detection of potential metastases in an early stage. Some NPs, such as superparamagnetic iron oxide NPs (SPIONs), are also compatible with magnetic resonance imaging (MRI), which makes their clinical translation and application rather easy and accessible for tumor imaging purposes. Furthermore, multifunctional and/or theranostic NPs can be used for simultaneous imaging of cancer and drug delivery. In this review article, we will specifically focus on the application of SPIONs in early detection and imaging of major cancer types. FROM THE CLINICAL EDITOR: Super-paramagnetic iron oxide nanoparticles (SPIONs) have been reported by many to be useful as an MRI contrast agent in the detection of tumors. To further enhance the tumor imaging, SPIONs can be coupled with tumor targeting motifs. In this article, the authors performed a comprehensive review on the current status of using targeted SPIONS in tumor detection and also the potential hurdles to overcome.


Asunto(s)
Medios de Contraste/química , Compuestos Férricos/química , Imagen por Resonancia Magnética/métodos , Imanes/química , Nanopartículas/química , Neoplasias/diagnóstico , Nanomedicina Teranóstica/métodos , Animales , Sistemas de Liberación de Medicamentos/métodos , Detección Precoz del Cáncer/métodos , Humanos , Metástasis de la Neoplasia/diagnóstico , Neoplasias/terapia
17.
Gastrointest Endosc ; 76(2): 293-300, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22817784

RESUMEN

BACKGROUND: EUS-guided FNA is one of the few techniques that can obtain cells and tissue from the liver and pancreas. However, the technique remains vulnerable to poor specimen quality and sampling error. OBJECTIVE: To evaluate the ability of a high-resolution microendoscope (HRME) to visualize the cellular and architectural features of normal and malignant liver and pancreatic tissue ex vivo, to assess the ability of endosonographers to identify normal and neoplastic tissue by using HRME images, and to demonstrate preliminary technical feasibility of in vivo HRME imaging via EUS fine-needle puncture (FNP). DESIGN: Ex vivo pilot feasibility study in human tissue; in vivo swine model. SETTING: Two academic medical centers. PATIENTS: Co-registered HRME images and biopsies were obtained from surgically resected hepatic and pancreatic tissues from 44 patients. INTERVENTION: Images were divided into training (12 images) and test (80 images) sets containing a range of normal and pathologic conditions for each organ. After viewing the training sets, 9 endosonographers attempted to distinguish malignant tissue from normal or benign lesions in the test sets, each of which contained 40 unique images with individual diagnoses from pathology. MAIN OUTCOME MEASUREMENTS: Image acquisition feasibility, ex vivo and in vivo. Ability of endosonographers to recognize features of normal/benign or malignant tissue from the liver and pancreas. RESULTS: Overall, the 9 endosonographers achieved median accuracy figures of 85% in the liver and 90% in the pancreas. The endosonographers with prior experience in reading HRME images achieved accuracy rates between 90% and 95%. Technical feasibility of HRME imaging through a 19-gauge EUS-FNP needle was demonstrated in an in vivo swine model. LIMITATIONS: Ex vivo study. CONCLUSION: High-resolution microendoscopy allows real-time imaging of cellular-level morphology and tissue architecture in the liver and pancreas. The technique appears to have a short learning curve, after which endosonographers achieved high accuracy rates in distinguishing malignant tissue from normal and benign pathology in both organs. Translating this imaging platform to the in vivo setting appears technically feasible.


Asunto(s)
Endoscopios , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/métodos , Neoplasias Hepáticas/patología , Hígado/patología , Microscopía/instrumentación , Páncreas/patología , Neoplasias Pancreáticas/patología , Animales , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico/instrumentación , Estudios de Factibilidad , Femenino , Humanos , Técnicas In Vitro , Curva de Aprendizaje , Hígado/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Páncreas/diagnóstico por imagen , Neoplasias Pancreáticas/diagnóstico por imagen , Proyectos Piloto , Porcinos
18.
Langmuir ; 28(26): 10091-6, 2012 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-22716764

RESUMEN

We report on the successful replication of the smallest pores in anodized aluminum oxide (AAO) via the layer-by-layer (LBL) deposition of polyelectrolytes to date to yield free-standing, open nanotubes with inner and outer diameters (±2σ) down to 37 ± 4 and 52 ± 19 nm, respectively. This work is based on the fabrication of defined arrays of highly regular nanopores by anodic oxidation of aluminum. Pores with pore diameters between 53 ± 9 and 356 ± 14 nm and interpore distances between 110 ± 3 and 500 ± 17 nm were obtained using an optimized two-step anodization procedure. 3-(Ethoxydimethylsilyl)propylamine-coated pores were replicated by alternating LBL deposition of poly(styrenesulfonate) and poly(allylamine). The detrimental adsorption of polyelectrolyte on the top surface of the template that typically results in partial pore blocking was eliminated by controlling the surface energy of the top surface via deposition of an ultrathin gold layer. The thickness of the deposited LBL multilayer assembly at the pore orifice agreed to within the experimental error with the thicknesses measured by variable angle spectroscopic ellipsometry and atomic force microscopy (AFM) for layers assembled on flat substrates. The selective dissolution of the alumina template afforded free-standing, open polymer nanotubes that were stable without any cross-linking procedure. The nanotubes thus obtained possessed mean outer diameters as small as 52 nm, limited by the size of the AAO template.

20.
Am J Surg Pathol ; 36(2): 305-10, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22189969

RESUMEN

Serous cystic neoplasms of the pancreas are generally considered benign lesions. Malignant counterparts have been occasionally described, and the diagnosis of malignancy is based solely on the presence of synchronous or metachronous metastases to the lymph nodes or liver, direct tumor invasion into adjacent organs, or vascular invasion. However, these malignant serous cystic tumors are lined by benign-appearing glycogen-rich cuboidal cells, which have been morphologically indistinguishable from benign microcystic serous cystadenoma in all the cases reported so far. We report a unique case of microcystic serous cystadenoma giving rise to carcinoma with distinctive histologic features including signet ring-like cells and solid nests. We believe that this case represents the first case of a cytologically malignant neoplasm arising from a benign serous cystadenoma (carcinoma ex microcystic serous cystadenoma).


Asunto(s)
Adenoma/patología , Neoplasias Pancreáticas/patología , Femenino , Humanos , Persona de Mediana Edad
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