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1.
Nano Lett ; 21(1): 389-396, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33337160

RESUMO

In parallel to the burgeoning field of soft electronics, soft plasmonics focuses on the design and fabrication of plasmonic structures supported on elastomers and to understand how their properties respond to mechanical deformations. Here, we report on a partial ligand-stripping strategy to fabricate elastomer-supported gold nanobipyramid (NBP) plasmene nanosheets. Unlike spherelike building blocks, NBP-building blocks display complex orientation-dependent plasmonic responses to external strains. By collecting polarized plasmonic resonance spectra in conjunction with electrostatic eigenmode modeling, we reveal simultaneous changes in interparticle spacing and spatial orientations of NBP building blocks under mechanical strains. Such changes are directly related to initial NBP packing orders. Further analysis of strain sensitivities for various NBP plasmenes indicated that plasmonic spectra of ∼45° oriented samples are mostly susceptible to strain at acute polarized angles. The results presented may enable novel applications in future soft optoelectronic devices in sensing, encryption, and data storage.


Assuntos
Ouro , Orientação Espacial , Elastômeros , Eletrônica
2.
Macromol Rapid Commun ; 41(1): e1900415, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31782585

RESUMO

Anti-reflective surfaces are of great interest for optical devices, sensing, photovoltaics, and photocatalysis. However, most of the anti-reflective surfaces lack in situ tunability of the extinction with respect to wavelength. This communication demonstrates a tunable anti-reflective surface based on colloidal particles comprising a metal core with an electrochromic polymer shell. Random deposition of these particles on a reflective surface results in a decrease in the reflectance of up to 99.8% at the localized surface plasmon resonance frequency. This narrow band feature can be tuned by varying the pH or by application of an electric potential, resulting in wavelength shifts of up to 30 nm. Electrophoretic particle deposition is shown to be an efficient method for controlling the interparticle distance and thereby further optimizing the overall efficiency of the anti-reflective metasurface.


Assuntos
Metais/química , Polímeros/química , Compostos de Anilina/química , Ouro/química , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/química , Tamanho da Partícula , Ressonância de Plasmônio de Superfície
3.
J Extra Corpor Technol ; 42(3): 199-202, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21114222

RESUMO

A recently completed study quantified the percent of fentanyl or morphine sulfate lost to uncoated polyvinylchloride (PVC) tubing or to one of two hollow fiber oxygenators within the extracorporeal life support (ECLS) circuit. The results demonstrated the majority of drug loss was due to adsorption by the PVC tubing. The purpose of this study was to determine if a tubing coating process affects fentanyl or morphine Sulfate adsorption. The goal was to quantify fentanyl or morphine sulfate lost due to adhesion within surface modified tubing. The following surface modifications were studied: 1) Maquet Safeline (synthetic immobilized albumin); 2) Maquet Softline (a heparin free biopassive polymer); 3) Maquet Bioline (recombinant human albumin + heparin) (Maquet Cardiopulmonary AG, Hirrlingen, Germany); 4) Terumo X Coating (poly2methoxylacrylate)) (Terumo Cardiovascular Systems Corporation, Ann Arbor, MI); 5) Medtronic Carmeda (covalently bonded heparin); and 6) Medtronic Trillium (covalently bonded heparin) (Medtronic, Minneapolis, MN). A total of 36 individual circuits were built from the above six available modified surface coatings, for a total of six individual circuits of each coating type. Blood samples were drawn at 5 minutes, 120 minutes, and 360 minutes followed by High-Performance Liquid Chromatography to determine available circulating levels of either fentanyl or morphine sulfate. Fentanyl concentrations decreased to an average final available concentration of 35% (+/- 5%) within the 18 circuits. Morphine sulfate however, decreased to a final available concentration of 57% (+ 1%) in all Maquet tubing and the Medtronic Trillium tubing, while it decreased to a final concentration of 35% (+ 1%) in the Medtronic Carmeda coated tubing and in the Terumo X Coating tubing. Biocompatible ECLS circuit surface coatings affected drug-adsorption and availability. Further evaluation is necessary to understand the adsorptive loss of other drugs administered to our patients while on modified surface coated ECLS circuits.


Assuntos
Materiais Revestidos Biocompatíveis , Circulação Extracorpórea/instrumentação , Fentanila/química , Morfina/química , Adsorção , Analgésicos/administração & dosagem , Analgésicos/farmacocinética , Fentanila/farmacocinética , Humanos , Hipnóticos e Sedativos/química , Hipnóticos e Sedativos/farmacocinética , Técnicas In Vitro , Morfina/farmacocinética , Cloreto de Polivinila , Propriedades de Superfície
4.
J Natl Cancer Inst ; 108(1)2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26577528

RESUMO

BACKGROUND: Although clinical studies have shown promise for targeting PD1/PDL1 signaling in non-small cell lung cancer (NSCLC), the regulation of PDL1 expression is poorly understood. Here, we show that PDL1 is regulated by p53 via miR-34. METHODS: p53 wild-type and p53-deficient cell lines (p53(-/-) and p53(+/+) HCT116, p53-inducible H1299, and p53-knockdown H460) were used to determine if p53 regulates PDL1 via miR-34. PDL1 and miR-34a expression were analyzed in samples from patients with NSCLC and mutated p53 vs wild-type p53 tumors from The Cancer Genome Atlas for Lung Adenocarcinoma (TCGA LUAD). We confirmed that PDL1 is a direct target of miR-34 with western blotting and luciferase assays and used a p53(R172HΔ)g/+K-ras(LA1/+) syngeneic mouse model (n = 12) to deliver miR-34a-loaded liposomes (MRX34) plus radiotherapy (XRT) and assessed PDL1 expression and tumor-infiltrating lymphocytes (TILs). A two-sided t test was applied to compare the mean between different treatments. RESULTS: We found that p53 regulates PDL1 via miR-34, which directly binds to the PDL1 3' untranslated region in models of NSCLC (fold-change luciferase activity to control group, mean for miR-34a = 0.50, SD = 0.2, P < .001; mean for miR-34b = 0.52, SD = 0.2, P = .006; and mean for miR-34c = 0.59, SD = 0.14, and P = .006). Therapeutic delivery of MRX34, currently the subject of a phase I clinical trial, promoted TILs (mean of CD8 expression percentage of control group = 22.5%, SD = 1.9%; mean of CD8 expression percentage of MRX34 = 30.1%, SD = 3.7%, P = .016, n = 4) and reduced CD8(+)PD1(+) cells in vivo (mean of CD8/PD1 expression percentage of control group = 40.2%, SD = 6.2%; mean of CD8/PD1 expression percentage of MRX34 = 20.3%, SD = 5.1%, P = .001, n = 4). Further, MRX34 plus XRT increased CD8(+) cell numbers more than either therapy alone (mean of CD8 expression percentage of MRX34 plus XRT to control group = 44.2%, SD = 8.7%, P = .004, n = 4). Finally, miR-34a delivery reduced the numbers of radiation-induced macrophages (mean of F4-80 expression percentage of control group = 52.4%, SD = 1.7%; mean of F4-80 expression percentage of MRX34 = 40.1%, SD = 3.5%, P = .008, n = 4) and T-regulatory cells. CONCLUSIONS: We identified a novel mechanism by which tumor immune evasion is regulated by p53/miR-34/PDL1 axis. Our results suggest that delivery of miRNAs with standard therapies, such as XRT, may represent a novel therapeutic approach for lung cancer.


Assuntos
Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma de Pulmão , Animais , Antígenos CD8/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Lipossomos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Camundongos , MicroRNAs/administração & dosagem , Neoplasias Experimentais/metabolismo
5.
Med Phys ; 42(12): 6784-97, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26632036

RESUMO

PURPOSE: Increasing evidence suggests radiomics features extracted from computed tomography (CT) images may be useful in prognostic models for patients with nonsmall cell lung cancer (NSCLC). This study was designed to determine whether such features can be reproducibly obtained from cone-beam CT (CBCT) images taken using medical Linac onboard-imaging systems in order to track them through treatment. METHODS: Test-retest CBCT images of ten patients previously enrolled in a clinical trial were retrospectively obtained and used to determine the concordance correlation coefficient (CCC) for 68 different texture features. The volume dependence of each feature was also measured using the Spearman rank correlation coefficient. Features with a high reproducibility (CCC > 0.9) that were not due to volume dependence in the patient test-retest set were further examined for their sensitivity to differences in imaging protocol, level of scatter, and amount of motion by using two phantoms. The first phantom was a texture phantom composed of rectangular cartridges to represent different textures. Features were measured from two cartridges, shredded rubber and dense cork, in this study. The texture phantom was scanned with 19 different CBCT imagers to establish the features' interscanner variability. The effect of scatter on these features was studied by surrounding the same texture phantom with scattering material (rice and solid water). The effect of respiratory motion on these features was studied using a dynamic-motion thoracic phantom and a specially designed tumor texture insert of the shredded rubber material. The differences between scans acquired with different Linacs and protocols, varying amounts of scatter, and with different levels of motion were compared to the mean intrapatient difference from the test-retest image set. RESULTS: Of the original 68 features, 37 had a CCC >0.9 that was not due to volume dependence. When the Linac manufacturer and imaging protocol were kept consistent, 4-13 of these 37 features passed our criteria for reproducibility more than 50% of the time, depending on the manufacturer-protocol combination. Almost all of the features changed substantially when scatter material was added around the phantom. For the dense cork, 23 features passed in the thoracic scans and 11 features passed in the head scans when the differences between one and two layers of scatter were compared. Using the same test for the shredded rubber, five features passed the thoracic scans and eight features passed the head scans. Motion substantially impacted the reproducibility of the features. With 4 mm of motion, 12 features from the entire volume and 14 features from the center slice measurements were reproducible. With 6-8 mm of motion, three features (Laplacian of Gaussian filtered kurtosis, gray-level nonuniformity, and entropy), from the entire volume and seven features (coarseness, high gray-level run emphasis, gray-level nonuniformity, sum-average, information measure correlation, scaled mean, and entropy) from the center-slice measurements were considered reproducible. CONCLUSIONS: Some radiomics features are robust to the noise and poor image quality of CBCT images when the imaging protocol is consistent, relative changes in the features are used, and patients are limited to those with less than 1 cm of motion.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Tomografia Computadorizada de Feixe Cônico/métodos , Tomografia Computadorizada de Feixe Cônico/instrumentação , Humanos , Movimento (Física) , Imagens de Fantasmas , Estruturas Vegetais , Radiografia Torácica/instrumentação , Radiografia Torácica/métodos , Reprodutibilidade dos Testes , Respiração , Estudos Retrospectivos , Borracha
6.
Rev. ADM ; 75(5): 261-268, sept.-oct. 2018. tab
Artigo em Espanhol | LILACS | ID: biblio-979930

RESUMO

Antecedentes: La caries tiene etiología multifactorial, se presenta por desbalance entre factores patológicos y protectores, es un problema de salud pública que en México afecta a 95% de los niños. Objetivo: Determinar la prevalencia de caries, establecer el nivel de riesgo y evaluar su relación con la incidencia de caries a los tres y seis meses. Material y métodos: Estudio observacional, descriptivo y longitudinal en clínica estomatológica de una universidad ubicada al sur de la Ciudad de México. Previo consentimiento informado, se realizó revisión bucal por dos cirujanos dentistas calibrados para el diagnóstico de caries/ICDAS (kappa 95.37%), llevada a cabo en sillón dental con luz artificial bajo principios para el control de infecciones. Se estableció nivel de riesgo mediante el Sistema Internacional para la Gestión de Caries/ICCMS empleando como indicadores: consumo de alimentos cariogénicos (Lipari/Andrade), pH (tiras Hidryon), prueba de saliva estimulada, experiencia de caries (CPOD/ceod), higiene bucal (O'Leary) y cultivo de Streptococcus mutans. Se realizó análisis estadístico para determinar medidas de tendencia central, dispersión y asociación entre variables mediante exacta de Fisher, STATA.SE/10. Resultados: La población en estudio fue de 42 niños con rango de edad de tres a 15 años, mediana de 7.04 (RIC = 5-9). La prevalencia de caries fue 95.23%, con estadios severos en 83.3%, el nivel de riesgo fue alto en 73.7% y se asoció con severidad de caries (p = 0.000), consumo de carbohidratos (p = 0.000), experiencia de caries (ceod) (p = 0.000) y S. mutans (p = 0.000). La incidencia de caries a los tres meses fue de 71.0% y a los seis meses de 11.1%. Conclusiones: La prevalencia de caries fue alta (95.23%) así como el riesgo de caries (73.7%), con elevada incidencia a tres meses (71%), aun cuando los pacientes estaban en tratamiento odontológico. La atención restaurativa prevalece a pesar de hacer diagnóstico de lesiones reversibles y determinación del nivel de riesgo (AU)


Background: Caries has multifactorial etiology, presented by the imbalance between pathological/protective factors, is a public health problem, affecting 95% of children in México. Objective: To determine the prevalence of caries, to establish the level of risk and to evaluate its relation with incidence of caries at three and six months. Material and methods: Observational, descriptive and longitudinal study in the stomatologic clinic of the UAM-Xochimilco. Before informed consent, oral revision was performed by two dental surgeons calibrated for the diagnosis of caries/ICDAS (kappa 95.37%), carried out in dental chair with artificial light under principles for the control of infections. Risk level was established through the International System for Caries Management/ICCMS; using as indicators: consumption of cariogenic foods (Lipari/Andrade), pH (Hidryon strips), stimulated saliva test, caries experience (CPOD/ceod), oral hygiene (O'Leary) and culture of Streptococcus mutans. Statistical analysis was performed to determine measures of central tendency, dispersion and association between variables with Fisher's exact, STATA.SE/10. Results: The study population consisted of 42 children with ages ranging from 3 to 15 years, median of 7.04 (Q1 = 5-Q3 = 9). The prevalence of caries was 95.23%, with severe stages in 83.3%, the risk level was high in 73.7% and was associated with caries severity (p = 0.000), carbohydrate consumption (p = 0.000), caries experience (ceod) (p = 0.000) and S. mutans (p = 0.000). The incidence of caries at three months was 71.0% and at six months 11.1%. Conclusions: The prevalence of caries was high (95.23%), as well as the risk for caries (73.7%), and high incidence at three months (71%), despite the fact that the patients were in dental treatment. Restorative care prevails despite the diagnosis of reversible lesions and determination of the level of risk (AU)


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Assistência Odontológica para Crianças , Cárie Dentária/epidemiologia , Suscetibilidade à Cárie Dentária , Educação Pré-Odontológica , Higiene Bucal , Índice CPO , Epidemiologia Descritiva , Interpretação Estatística de Dados , Estudos Longitudinais , Medição de Risco , Dieta Cariogênica , Estudo Observacional , México
7.
Foot Ankle Clin ; 17(3): 449-57, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22938643

RESUMO

PEEK cages are an effective alternative when structural bone graft is needed for different fusions around the foot and ankle. Bone fusion rates are high when PEEK cages are filled with autologous bone. No difference in consolidation time in patients was noticed between the cages fixed with staples and those fixed with cannulated screws. Nerve damage, residual pain at the donor site, and cosmetic problems are avoided with the use of PEEK cages. There is no risk of transmission of hepatitis B, hepatitis C, and HIV when using PEEK cages.


Assuntos
Articulação do Tornozelo/cirurgia , Materiais Biocompatíveis , Pé/cirurgia , Cetonas , Polietilenoglicóis , Benzofenonas , Feminino , Humanos , Masculino , Polímeros
8.
Int J Radiat Oncol Biol Phys ; 81(4): e207-13, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-21570202

RESUMO

PURPOSE: Osteoradionecrosis (ORN) is a known complication of radiation therapy to the head and neck. However, the incidence of this complication with intensity-modulated radiation therapy (IMRT) and dental sequelae with this technique have not been fully elucidated. METHODS AND MATERIALS: From December 2000 to July 2007, 168 patients from our institution have been previously reported for IMRT of the oral cavity, nasopharynx, larynx/hypopharynx, sinus, and oropharynx. All patients underwent pretreatment dental evaluation, including panoramic radiographs, an aggressive fluoride regimen, and a mouthguard when indicated. The median maximum mandibular dose was 6,798 cGy, and the median mean mandibular dose was 3,845 cGy. Patient visits were retrospectively reviewed for the incidence of ORN, and dental records were reviewed for the development of dental events. Univariate analysis was then used to assess the effect of mandibular and parotid gland dosimetric parameters on dental endpoints. RESULTS: With a median clinic follow-up of 37.4 months (range, 0.8-89.6 months), 2 patients, both with oral cavity primaries, experienced ORN. Neither patient had preradiation dental extractions. The maximum mandibular dose and mean mandibular dose of the 2 patients were 7,183 and 6,828 cGy and 5812 and 5335 cGy, respectively. In all, 17% of the patients (n = 29) experienced a dental event. A mean parotid dose of >26 Gy was predictive of a subsequent dental caries, whereas a maximum mandibular dose >70 Gy and a mean mandibular dose >40 Gy were correlated with dental extractions after IMRT. CONCLUSIONS: ORN is rare after head-and-neck IMRT, but is more common with oral cavity primaries. Our results suggest different mechanisms for radiation-induced caries versus extractions.


Assuntos
Cárie Dentária/etiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Doenças Mandibulares/etiologia , Osteorradionecrose/etiologia , Glândula Parótida/efeitos da radiação , Radioterapia de Intensidade Modulada/efeitos adversos , Extração Dentária/estatística & dados numéricos , Análise de Variância , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Doenças Mandibulares/cirurgia , Osteorradionecrose/cirurgia , Dosagem Radioterapêutica , Estudos Retrospectivos
9.
Nat Commun ; 2: 237, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21407203

RESUMO

With controlled nanometre-sized pores and surface areas of thousands of square metres per gram, metal-organic frameworks (MOFs) may have an integral role in future catalysis, filtration and sensing applications. In general, for MOF-based device fabrication, well-organized or patterned MOF growth is required, and thus conventional synthetic routes are not suitable. Moreover, to expand their applicability, the introduction of additional functionality into MOFs is desirable. Here, we explore the use of nanostructured poly-hydrate zinc phosphate (α-hopeite) microparticles as nucleation seeds for MOFs that simultaneously address all these issues. Affording spatial control of nucleation and significantly accelerating MOF growth, these α-hopeite microparticles are found to act as nucleation agents both in solution and on solid surfaces. In addition, the introduction of functional nanoparticles (metallic, semiconducting, polymeric) into these nucleating seeds translates directly to the fabrication of functional MOFs suitable for molecular size-selective applications.


Assuntos
Compostos Organometálicos/análise , Fosfatos/análise , Polímeros/análise , Compostos de Zinco/análise , Técnicas Biossensoriais/métodos , Catálise , Cristalização/métodos , Modelos Moleculares , Compostos Organometálicos/síntese química , Compostos Organometálicos/metabolismo , Fosfatos/síntese química , Fosfatos/metabolismo , Polímeros/síntese química , Polímeros/metabolismo , Pontos Quânticos , Semicondutores , Soluções/química , Propriedades de Superfície , Compostos de Zinco/síntese química , Compostos de Zinco/metabolismo
10.
Int J Radiat Oncol Biol Phys ; 73(4): 1096-103, 2009 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18707827

RESUMO

PURPOSE: To present our single-institution experience of intensity-modulated radiotherapy (IMRT) for oral cavity cancer. METHODS AND MATERIALS: Between September 2000 and December 2006, 35 patients with histologically confirmed squamous cell carcinoma of the oral cavity underwent surgery followed by postoperative IMRT. The sites included were buccal mucosa in 8, oral tongue in 11, floor of the mouth in 9, gingiva in 4, hard palate in 2, and retromolar trigone in 1. Most patients had Stage III-IV disease (80%). Ten patients (29%) also received concurrent postoperative chemotherapy with IMRT. The median prescribed radiation dose was 60 Gy. RESULTS: The median follow-up for surviving patients was 28.1 months (range, 11.9-85.1). Treatment failure occurred in 11 cases as follows: local in 4, regional in 2, and distant metastases in 5. Of the 5 patients with distant metastases, 2 presented with dermal metastases. The 2- and 3-year estimates of locoregional progression-free survival, distant metastasis-free survival, disease-free survival, and overall survival were 84% and 77%, 85% and 85%, 70% and 64%, and 74% and 74%, respectively. Acute Grade 2 or greater dermatitis, mucositis, and esophageal reactions were experienced by 54%, 66%, and 40% of the patients, respectively. Documented late complications included trismus (17%) and osteoradionecrosis (5%). CONCLUSION: IMRT as an adjuvant treatment after surgical resection for oral cavity tumors is feasible and effective, with promising results and acceptable toxicity.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Neoplasias Bucais/radioterapia , Radioterapia de Intensidade Modulada/métodos , Idoso , Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/mortalidade , Neoplasias Bucais/cirurgia , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Radioterapia Adjuvante , Radioterapia de Intensidade Modulada/efeitos adversos , Estudos Retrospectivos
12.
Rev. biol. trop ; 49(1): 31-45, Mar. 2001.
Artigo em Espanhol | LILACS | ID: lil-320089

RESUMO

The fish and invertebrates community structure in the Sabancuy estuary was analyzed in two seasons and 14 sampling stations (13 along the estuary and one in the marine adjacent coast). No significant differences were found between seasons. The environmental frame defines two zones within the estuary, the first extends from the access highway to Sabancuy town until the Pujo mouth in the west; the second from the bridge to the estuary head in the east. The most abundant invertebrates were mollusks (51.8 of the total), in biomass the crustaceans dominated. The fish included 21 families and 33 species; the most abundant were Gerridae, Scianidae, Sparidae, Lutjanidae and Ciprinodontidae. The highest diversities of both communities correspond to the central part of the estuary. These communities include three sections with notable differences in faunal distribution: one is influenced by the exit to Terminos lagoon, the secondary in the estuary head and a third is in a transition zone defined by the proximity of the town access bridge. The ecological organization suggests a strong division caused by the bridge, both sides are scarce in habitats and nutrient resources and this is reflected in the low species counts.


Assuntos
Animais , Peixes , Água Doce , Invertebrados , Água do Mar , Biomassa , Ecossistema , México , Densidade Demográfica , Estações do Ano
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