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1.
Clin Lymphoma Myeloma Leuk ; 22(10): e947-e957, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35858904

RESUMO

BACKGROUND: Managing double-expressor lymphomas (DEL) is controversial given the dearth of data and lack of standardized guidelines on this high-risk subset of lymphomas. No prospective and few retrospective studies limited by either their sample size or short follow-up address the question of initial treatment of choice for DEL. We performed the largest analysis to date exploring R-CHOP vs DA-EPOCH-R in DEL. METHODS: Adults with DEL diagnosed from 6/2012-2/2021 at 4 unique sites were retrospectively analyzed. Progression-free survival (PFS) was the primary endpoint. Key secondary endpoints include overall survival (OS), overall and complete response rates (ORR and CRR), cumulative incidence of relapse, and autologous hematopoietic cell transplantation (autoHCT) utilization. RESULTS: 155 patients were included, 61 treated with R-CHOP and 94 with DA-EPOCH-R. 3-year PFS and OS were similar between R-CHOP and DA-EPOCH-R, 33.2% vs 57.2%,(P = .063), and 72.2% vs 71.6% (P = .43) after median follow-up times of 2.43 and 2.89 years, respectively. Patients <65 had improved PFS with DA-EPOCH-R, hazard ratio 0.41 (P = .01). CRR and ORR rates were also similar. Relapse rates were not statistically different, 51.9% vs 28.6% (P = .069). AutoHCT utilization was higher with R-CHOP vs DA-EPOCH-R, 23.0% vs 8.5% (P = .017). CONCLUSIONS: Our findings do not support the use of DA-EPOCH-R over R-CHOP for DEL. Patients <65 years may experience longer PFS with DA-EPOCH-R, but limitations to the analysis make this interpretation difficult.


Assuntos
Neoplasias Hematológicas , Linfoma Difuso de Grandes Células B , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Etoposídeo , Neoplasias Hematológicas/etiologia , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Recidiva Local de Neoplasia , Prednisona/uso terapêutico , Estudos Retrospectivos , Rituximab/uso terapêutico , Vincristina/uso terapêutico
2.
Int. j. morphol ; 36(4): 1463-1471, Dec. 2018. graf
Artigo em Espanhol | LILACS | ID: biblio-975723

RESUMO

Los materiales poliméricos han sido ampliamente investigados para aplicaciones biomédicas, teniendo especial relevancia cuando se encuentran en forma de micro- y nano-partículas. Últimamente se ha ampliado su campo de aplicación al ser conjugados con péptidos y ácidos nucleicos, por lo tanto, el interés en el estudio de este tipo de materiales, así como también en la formulación de nanoestructuras funcionalizadas como materiales, dispositivos y vehículos de transporte de agentes terapéuticos ha aumentado. Las recientes investigaciones en nanosistemas se inspiran en fenómenos naturales que estimulan la integración de señales moleculares y la mimetización de procesos a nivel celular, de tejidos y órganos. Tecnológicamente, la capacidad de obtener nanoestructuras esféricas mediante la combinación de materiales que presenten propiedades distintas a las que ningún otro material individual posee por sí solo, es lo que hace que las nanocápsulas sean particularmente atractivas. Las potenciales ventajas de los sistemas de nanopartículas de tipo polimérico se destacan a lo largo de cada parte de este artículo de revisión. El presente artículo aborda los aspectos más relevantes sobre la estructura, composición y algunos métodos de elaboración de los sistemas nanoparticulados. Además, expone algunos de los trabajos más recientes, centrados en sistemas de nanopartículas basados en polímeros dirigidos a la administración de agentes, publicados en artículos especializados de investigación y revisiones durante los últimos años.


Polymeric materials have been extensively investigated for biomedical applications including micro- and nanoparticles. Modern advances have broadened horizons for application with peptides and nucleic acids. Therefore, interests increased in the formulation of materials, devices and vehicles for transporting therapeutic agents in functionalized nanostructures. Recent nano-systems are inspired by natural phenomena that stimulate the integration of molecular signals and the mimicking of natural cellular processes, at tissue and organ levels. Technologically, the ability to obtain spherical nanostructures, which combine different properties, that no other single material possesses on its own, makes nanocapsules particularly attractive. Potential advantages over polymer nanoparticulate systems are highlighted throughout each part of this review article. Here, we address the most relevant aspects of structure, composition and methods of formulation of nanoparticulate systems. In addition, we outline some of the more recent works focusing on nanosized preparations, based on agent-directed polymers, found in specialized research articles that have emerged in the recent years.


Assuntos
Polímeros/química , Nanopartículas/química , Sistemas de Liberação de Medicamentos , Engenharia Tecidual , Pontos Quânticos , Nanocápsulas/química , Nanosferas/química
3.
Int. j. morphol ; 36(4): 1490-1499, Dec. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-975727

RESUMO

Nanotecnología es la ciencia que involucra la síntesis de materiales en escala entre 1-100 nm (nanomateriales) es aplicable en diferentes áreas tales como medio ambiente, electrónica, alimentos, energía, entre otros. Los campos que serán relevantes dentro de esta revisión y explicados en detalle son la nanomedicina y la nano-odontología. Actualmente, en estas áreas los tres principales temas en desarrollo son específicamente en el sub-área de la nanobiotecnología y corresponden a: sensorización (biosensores/biodetección), diagnóstico (biomarcadores/bioimagen) y transportes de genes, proteínas o fármacos (sistemas de intercambio controlado en blancos sistémicos versus localizados). También se han presentado avances en bioaplicaciones como modelamientos de membranas, marcaje celular, entrega de agentes a blancos específicos, estrategias para prevención de enfermedades, ingeniería de tejidos, regeneración de órganos, estrategias de inmunoensayos y nano-oncología. Este artículo de revisión pretende abordar algunos de los aportes más relevantes, que tienen algunos de los trabajos recientes, sobre los sistemas de nanopartículas, principalmente aquellos dirigidos a terapias en áreas como diabetes, nano-oncología, terapia de fármacos y genes, mediante la técnica layer-by-layer y autoensamblado, muy utilizados también en ingeniería de tejidos y regeneración tisular, junto a un breve resumen de los avances que existen en el campo de la nano-odontología.


Nanotechnology is the science that involves the synthesis of materials in scale between 1-100 nm (nanomaterials) and is applicable in different areas such as environment, electronics, food, energy, among others. The fields that will be relevant within this review and explained in detail are nanomedicine and nano-dentistry. Currently, in these areas, the three main topics under development are specifically in the sub-area of nanobiotechnology and correspond to: sensorization (biosensors / biosensing), diagnostics (biomarkers / bioimaging) and transport of genes, proteins or drugs (exchange systems) controlled in systemic versus localized targets). Advances have also been presented in bioapplications such as membrane modeling, cell marking, delivery of agents to specific targets, strategies for disease prevention, tissue engineering, organ regeneration, immunoassay strategies and nano-oncology. This review article aims to address some of the most relevant contributions, some of the recent work, on nanoparticle systems, mainly those aimed at therapies in areas such as diabetes, nanooncology, drug and gene therapy, through the layer-by-layer and self-assembled technique, also widely used in tissue engineering and tissue regeneration, together with a brief summary of the advances that exist in the field of nano-dentistry.


Assuntos
Nanomedicina/tendências , Polímeros/química , Regeneração Óssea , Técnicas Biossensoriais , Terapia Genética , Sistemas de Liberação de Medicamentos , Engenharia Tecidual , Nanotecnologia , Odontologia/tendências , Pontos Quânticos , Oncologia/tendências
4.
J Biol Chem ; 292(44): 18129-18144, 2017 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-28893905

RESUMO

Lysine acetylation is a widespread posttranslational modification affecting many biological pathways. Recent studies indicate that acetylated lysine residues mainly exhibit low acetylation occupancy, but challenges in sample preparation and analysis make it difficult to confidently assign these numbers, limiting understanding of their biological significance. Here, we tested three common sample preparation methods to determine their suitability for assessing acetylation stoichiometry in three human cell lines, identifying the acetylation occupancy in more than 1,300 proteins from each cell line. The stoichiometric analysis in combination with quantitative proteomics also enabled us to explore their functional roles. We found that higher abundance of the deacetylase sirtuin 1 (SIRT1) correlated with lower acetylation occupancy and lower levels of ribosomal proteins, including those involved in ribosome biogenesis and rRNA processing. Treatment with the SIRT1 inhibitor EX-527 confirmed SIRT1's role in the regulation of pre-rRNA synthesis and processing. Specifically, proteins involved in pre-rRNA transcription, including subunits of the polymerase I and SL1 complexes and the RNA polymerase I-specific transcription initiation factor RRN3, were up-regulated after SIRT1 inhibition. Moreover, many protein effectors and regulators of pre-rRNA processing needed for rRNA maturation were also up-regulated after EX-527 treatment with the outcome that pre-rRNA and 28S rRNA levels also increased. More generally, we found that SIRT1 inhibition down-regulates metabolic pathways, including glycolysis and pyruvate metabolism. Together, these results provide the largest data set thus far of lysine acetylation stoichiometry (available via ProteomeXchange with identifier PXD005903) and set the stage for further biological investigations of this central posttranslational modification.


Assuntos
Regulação da Expressão Gênica , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Precursores de RNA/metabolismo , Processamento Pós-Transcricional do RNA , RNA Ribossômico/metabolismo , Sirtuína 1/metabolismo , Acetilação/efeitos dos fármacos , Métodos Analíticos de Preparação de Amostras , Carbazóis/farmacologia , Linhagem Celular Transformada , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Cinética , Mapeamento de Peptídeos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteômica/métodos , Processamento Pós-Transcricional do RNA/efeitos dos fármacos , RNA Ribossômico 28S/metabolismo , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/genética , Espectrometria de Massas em Tandem
5.
Univ. salud ; 19(2): 186-196, mayo-ago. 2017. tab, graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-904654

RESUMO

Resumen Introducción: Los actos de cuidado que ofrece la Enfermería se fundamentan en la relación enfermero-paciente, el respeto por la dignidad y autonomía de las personas. Esto implica, comprender la importancia y el significado desde su esfera humana, aspecto que le otorga un sentido ético a las prácticas de cuidado. Este proceso reflexivo, amerita un adecuado conocimiento de las acciones que son necesarias para obtener el consentimiento informado. Objetivo: Identificar el conocimiento e importancia que los profesionales de enfermería tienen sobre el consentimiento informado, aplicado en los actos de cuidado, basado en la teoría de los patrones del conocimiento. Materiales y métodos: Estudio descriptivo, cuantitativo, transversal con una muestra de 221 profesionales de Enfermería, a quienes se les aplicó un cuestionario tipo escala de Likert; para el análisis se empleó estadística descriptiva, análisis factorial e inferencial. Resultados: Se evidenció poco conocimiento sobre el uso del consentimiento informado en los participantes. La variable importancia, se centra en el aspecto legal, administrativo e instrumental del consentimiento informado. Conclusión: Se debe fomentar el uso del consentimiento informado en actos de cuidado de la profesión. Así como los aspectos éticos, reforzar las formas de explicar los riesgos, beneficios y alternativas al paciente.


Abstract Introduction: Nursing acts are based on the nurse-patient relationship, respect for the dignity and autonomy of people. This implies understanding the importance and meaning from the human sphere, which is an aspect that gives an ethical sense of care practices. This reflective process deserves adequate knowledge of the actions that are necessary to obtain the informed consent. Objective: Identify the knowledge and importance that nursing professionals have about the informed consent applied in the acts of care, based on the theory of knowledge patterns. Materials and methods: A descriptive, quantitative, cross-sectional study was conducted with a sample of 221 nursing professionals, who undertook a questionnaire type Likert scale. Descriptive statistics, factorial and inferential analysis were applied for the analysis. Results: It could be seen that there was little knowledge about the use of informed consent in the participants. The variable called importance is focused on the legal, administrative and instrumental aspect of the informed consent. Conclusion: The use of informed consent should be encouraged in acts of care of the profession. The ways to explain the risks, benefits and alternatives to the patient must be reinforced as well as the ethical aspects.


Assuntos
Humanos , Consentimento Livre e Esclarecido , Ética em Enfermagem , Cuidados de Enfermagem , Autonomia Pessoal
6.
J Nanobiotechnology ; 15(1): 1, 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-28049488

RESUMO

BACKGROUND: Nanotechnology is a science that involves imaging, measurement, modeling and a manipulation of matter at the nanometric scale. One application of this technology is drug delivery systems based on nanoparticles obtained from natural or synthetic sources. An example of these systems is synthetized from poly(3-hydroxybutyrate-co-3-hydroxyvalerate), which is a biodegradable, biocompatible and a low production cost polymer. The aim of this work was to investigate the uptake mechanism of PHBV nanoparticles in two different epithelial cell lines (HeLa and SKOV-3). RESULTS: As a first step, we characterized size, shape and surface charge of nanoparticles using dynamic light scattering and transmission electron microscopy. Intracellular incorporation was evaluated through flow cytometry and fluorescence microscopy using intracellular markers. We concluded that cellular uptake mechanism is carried out in a time, concentration and energy dependent way. Our results showed that nanoparticle uptake displays a cell-specific pattern, since we have observed different colocalization in two different cell lines. In HeLa (Cervical cancer cells) this process may occur via classical endocytosis pathway and some internalization via caveolin-dependent was also observed, whereas in SKOV-3 (Ovarian cancer cells) these patterns were not observed. Rearrangement of actin filaments showed differential nanoparticle internalization patterns for HeLa and SKOV-3. Additionally, final fate of nanoparticles was also determined, showing that in both cell lines, nanoparticles ended up in lysosomes but at different times, where they are finally degraded, thereby releasing their contents. CONCLUSIONS: Our results, provide novel insight about PHBV nanoparticles internalization suggesting that for develop a proper drug delivery system is critical understand the uptake mechanism.


Assuntos
Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos , Nanopartículas/metabolismo , Neoplasias/tratamento farmacológico , Poliésteres/metabolismo , Transporte Biológico , Linhagem Celular Tumoral , Endocitose , Células HeLa , Humanos , Nanopartículas/ultraestrutura
7.
Nanoscale Res Lett ; 11(1): 66, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26847692

RESUMO

Poly(amidoamine) dendrimers are the most recognized class of dendrimer. Amino-terminated (PAMAM-NH2) and hydroxyl-terminated (PAMAM-OH) dendrimers of generation 4 are widely used, since they are commercially available. Both have different properties, mainly based on their different overall charges at physiological pH. Currently, an important function of dendrimers as carriers of short single-stranded DNA has been applied. These molecules, known as antisense oligonucleotides (asODNs), are able to inhibit the expression of a target mRNA. Whereas PAMAM-NH2 dendrimers have shown to be able to transfect plasmid DNA, PAMAM-OH dendrimers have not shown the same successful results. However, little is known about their interaction with shorter and more flexible molecules such as asODNs. Due to several initiatives, the use of these neutral dendrimers as a scaffold to introduce other functional groups has been proposed. Because of its low cytotoxicity, it is relevant to understand the molecular phenomena involving these types of dendrimers. In this work, we studied the behavior of an antisense oligonucleotide in presence of both types of dendrimers using molecular dynamics simulations, in order to elucidate if they are able to form stable complexes. In this manner, we demonstrated at atomic level that PAMAM-NH2, unlike PAMAM-OH, could form a well-compacted complex with asODN, albeit PAMAM-OH can also establish stable interactions with the oligonucleotide. The biological activity of asODN in complex with PAMAM-NH2 dendrimer was also shown. Finally, we revealed that in contact with PAMAM-OH, asODN remains outside the cells as TIRF microscopy results showed, due to its poor interaction with this dendrimer and cell membranes.

12.
Curr Pharm Biotechnol ; 15(9): 864-79, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25213311

RESUMO

Recent advances in nanotechnology and nanobiotechnology have contributed to the development of nanomaterials, able to be used as drug carriers, probes, targets or cytostatic drugs by itself. Nanomedicine is now the leading area in nanotechnology where a large number and types of nanoparticles (NPs) has been developed and several are already in the clinical practice. Chemotherapy is one of the most widely used strategies to treat cancer. Most chemotherapeutic agents have poor solubility, low bioavailability, and are formulated with toxic solvents. NPs have been designed to overcome the lack of specificity of chemotherapeutic agents as well to improve circulation time in blood, taking advantages on tumor cells characteristics. In immunology, recent advances regarding the activation of the innate immune system artificially enhanced by NPs functionalized with immune-stimulators open a new window as novel methods in vaccines. Also, viruses and virus-like particles (VLPs) engineered to stimulate immune response against their similar virus or as molecular platforms for the presentation of foreign epitopes have been described. In this review we focused in the use of different types of NPs in oncology and immunology, pinpointing the main novelties regarding their development and use of nanotechnology in a broad array of applications, ranging from tumor diagnostics, immune-modulation up to cancer therapeutics.


Assuntos
Antineoplásicos , Fatores Imunológicos , Nanopartículas , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Dendrímeros/química , Grafite/química , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/química , Fatores Imunológicos/uso terapêutico , Lipossomos , Nanomedicina , Nanopartículas/administração & dosagem , Nanopartículas/química , Nanopartículas/uso terapêutico , Nanotubos de Carbono/química , Neoplasias/tratamento farmacológico , Dióxido de Silício/química
13.
Fundam Clin Pharmacol ; 28(6): 593-607, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24750474

RESUMO

Since its discovery, cAMP has been proposed as one of the most versatile second messengers. The remarkable feature of cAMP to tightly control highly diverse physiological processes, including metabolism, homeostasis, secretion, muscle contraction, cell proliferation and migration, immune response, and gene transcription, is reflected by millions of different articles worldwide. Compartmentalization of cAMP in space and time, maintained by mainly phosphodiesterases, contributes to the maintenance of equilibrium inside the cell where one signal can trigger many different events. Novel cAMP sensors seem to carry out certain unexpected signaling properties of cAMP and thereby to permit delicate adaptations of biologic responses. Measuring space and time events with biosensors will increase our current knowledge on the pathophysiology of diseases, such as chronic obstructive pulmonary disease, asthma, cognitive impairment, cancer, and renal and heart failure. Further insights into the cAMP dynamics will help to optimize the pharmacological treatment for these diseases.


Assuntos
AMP Cíclico/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Transdução de Sinais/fisiologia , Animais , Técnicas Biossensoriais , Humanos
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