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1.
Virol J ; 21(1): 113, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38760812

RESUMEN

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease. SFTS virus (SFTSV) is transmitted by tick bites and contact with the blood or body fluids of SFTS patients. Animal-to-human transmission of SFTS has been reported in Japan, but not in China. In this study, the possible transmission route of two patients who fed and cared for farm-raised fur animals in a mink farm was explored. METHOD: An epidemiological investigation and a genetic analysis of patients, animals and working environment were carried out. RESULTS: It was found that two patients had not been bitten by ticks and had no contact with patients infected with SFTS virus, but both of them had skinned the dying animals. 54.55% (12/22) of the farm workers were positive for SFTS virus antibody. By analyzing the large, medium and small segments sequences, the viral sequences from the two patients, animals and environments showed 99.9% homology. CONCLUSION: It is suspected that the two patients may be directly infected by farm-raised animals, and that the virus may have been transmitted by aerosols when skinning dying animals. Transmission by direct blood contacts or animal bites cannot be ignored.


Asunto(s)
Phlebovirus , Síndrome de Trombocitopenia Febril Grave , Animales , Phlebovirus/genética , Phlebovirus/aislamiento & purificación , Phlebovirus/clasificación , China/epidemiología , Síndrome de Trombocitopenia Febril Grave/transmisión , Síndrome de Trombocitopenia Febril Grave/virología , Síndrome de Trombocitopenia Febril Grave/epidemiología , Humanos , Masculino , Anticuerpos Antivirales/sangre , Filogenia , Femenino , Persona de Mediana Edad , Visón/virología , Granjas , Adulto , Agricultores , ARN Viral/genética
2.
Front Public Health ; 11: 1273443, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38035306

RESUMEN

COVID-19 is an acute respiratory infectious disease caused by SARS-CoV-2. It was first reported in Wuhan, China in December 2019 and rapidly spread globally in early 2020, triggering a global pandemic. In December 2022, China adjusted the dynamic COVID-zero strategy that lasted for three years. The number of positive cases in China increased rapidly in the short term. Weihai was also affected during this period. We conducted genomic surveillance of SARS-CoV-2 variants in Weihai during this period, hoping to understand the changes in the genomic characteristics of SARS-CoV-2 before and after the adjustment of the epidemic policy. In this study,we collected SARS-CoV-2 positive samples from March 2022 to March 2023 in Weihai and performed SARS-CoV-2 whole genome sequencing on these samples using next-generation sequencing technology. we obtained a total of 704 SARS-CoV-2 whole genome sequences, and selected 581 high-quality sequences for further analysis. The analysis results showed that from March 2022 to November 2022, before the adjustment of epidemic policy, the COVID-19 cases in Weihai were mainly from four local clusters,which were caused by four variants, including BA.2,BA.1.1,P.1.15 and BA.5.2.1. Phylogenetic analysis showed that: In the same cluster,the sequences between each other were highly homologous, and the whole genome sequence were almost identical. After December 2022, the epidemic policy was adjusted, BF.7 and BA.5.2 became the dominant variants in Weihai, consistent with the main domestic strains in China during the same period. Phylodynamic analysis showed that BF.7 and BA.5.2 had a large amount of genetic diversities in December, and the effective population size of BF.7 and BA.5.2 also showed explosive growth in December. In conclusion, we reported the composition and dynamic trend of SARS-CoV-2 variants in Weihai from March 2022 to March 2023. We found that there have been significant changes in the variants and expansion patterns of SARS-CoV-2 before and after the adjustment of epidemic policies. But the dominant variants in Weihai were the same as the SARS-CoV-2 variants circulating globally at the same time and we found no persistently dominant variants or new lineages during this period.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Filogenia , COVID-19/epidemiología , Genómica , China/epidemiología , Pandemias
3.
Rev. bras. med. esporte ; 29: e2022_0376, 2023. tab
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1407644

RESUMEN

ABSTRACT Introduction: Martial arts comprise skill-based fighting games whose early specialized training is essential for development. Martial arts techniques are based on body movements requiring physical coordination, body stability, and endurance. Objective: Design a specific training for the abdominal center in martial arts athletes. Methods: Twelve martial arts athletes were selected as research subjects. These athletes were submitted to experimental training for six semesters. According to the characteristics of movement and effort, this paper evaluates the capacity of athletes' abdominal center muscle groups. The content of the experimental training included stability, strength, explosiveness, and endurance. The experimental results were analyzed based on current scientific literature and mathematical statistics. Results: Compared to the test before the experiment, the stabilization strength of the abdominal core muscles in routine training was unchanged without statistical significance (P>0.05). After six weeks of experimental core strength training, core muscle stability strength was significantly increased (P<0.001). Conclusion: The abdominal core stability of martial arts athletes was improved by experience. Its positive performance was in martial arts athletes' stability, strength, explosive power, and endurance. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.


RESUMO Introdução: Artes marciais compreendem jogos de luta baseados em habilidades cujo treinamento especializado precoce é essencial para o seu desenvolvimento. As técnicas das artes marciais são baseadas nos movimentos corporais requerendo coordenação física, estabilidade corporal e resistência. Objetivo: Elaborar um treinamento específico para o core em atletas de artes marciais. Métodos: Doze atletas de artes marciais foram selecionados como objetos de pesquisa. Esses atletas foram submetidos ao treino experimental por seis semestres. De acordo com as características de movimento e esforço, este artigo avalia a capacidade dos grupos musculares do core dos atletas. O conteúdo do treinamento experimental incluiu estabilidade, força, explosividade e resistência. A análise dos resultados experimentais efetuou-se com embasamento da literatura científica atual e estatísticas matemáticas. Resultados: Em comparação com o teste prévio ao experimento, a força de estabilização dos músculos do núcleo abdominal no treinamento de rotina foi inalterada, sem significância estatística (P>0,05). Após seis semanas de treinamento experimental da força do core, a força da estabilidade do núcleo muscular foi significativamente aumentada (P<0,001). Conclusão: A estabilidade do core dos atletas de artes marciais foi aprimorada pela experiência. Seu desempenho positivo deu-se na estabilidade, força, poder explosivo e resistência dos atletas de artes marciais. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.


RESUMEN Introducción: Las artes marciales comprenden juegos de lucha basados en la habilidad, cuyo entrenamiento especializado temprano es esencial para su desarrollo. Las técnicas de las artes marciales se basan en movimientos corporales que requieren coordinación física, estabilidad corporal y resistencia. Objetivo: Diseñar un entrenamiento específico para el core en atletas de artes marciales. Métodos: Se seleccionaron doce atletas de artes marciales como sujetos de la investigación. Estos atletas fueron sometidos al entrenamiento experimental durante seis semestres. Según las características del movimiento y el esfuerzo, este artículo evalúa la capacidad de los grupos musculares del core de los atletas. El contenido del entrenamiento experimental incluía estabilidad, fuerza, explosividad y resistencia. El análisis de los resultados experimentales se basó en la literatura científica actual y en la estadística matemática. Resultados: En comparación con la prueba anterior al experimento, la fuerza de estabilización de los músculos abdominales centrales en el entrenamiento de rutina no se modificó sin significación estadística (P>0,05). Después de seis semanas de entrenamiento experimental de la fuerza del núcleo, la fuerza de estabilidad de los músculos del núcleo aumentó significativamente (P<0,001). Conclusión: La estabilidad del core de los atletas de artes marciales mejoró con el experimento. Su rendimiento positivo fue en la estabilidad, la fuerza, la potencia explosiva y la resistencia de los atletas de artes marciales. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

4.
ACS Appl Mater Interfaces ; 10(43): 36641-36651, 2018 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-30360129

RESUMEN

Drug development involves various evaluation processes to ascertain drug effects and rigorous analysis of biological indicators during in vitro preclinical studies. Two-dimensional (2D) cell cultures are commonly used in numerous in vitro studies, which are poor facsimiles of the in vivo conditions. Recently, three-dimensional (3D) tumor models mimicking the tumor microenvironment and reducing the use of experimental animals have been developed generating great interest to appraise tumor response to treatment strategies in cancer therapy. In this study, silk fibroin (SF) protein and chitosan (CS), two natural biomaterials, were chosen to construct the scaffolds of 3D cell models. Human non-small cell lung cancer A549 cells in the SF/CS scaffolds were found to have a great tendency to gather and form tumor spheres. A549 cell spheres in the 3D scaffolds showed biological and morphological characteristics much closer to the in vivo tumors. Besides, the cells in 3D models displayed better invasion ability and drug resistance than 2D models. Additionally, differences in drug-resistant and immune-related protein levels were found, which indicated that 3D models might resemble the real-life situation. These findings suggested that these 3D tumor models composed of SF/CS are promising to provide a valuable biomaterial platform in the evaluation of anticancer drugs.


Asunto(s)
Quitosano/química , Sistemas de Liberación de Medicamentos , Evaluación Preclínica de Medicamentos/métodos , Fibroínas/química , Neoplasias Pulmonares/tratamiento farmacológico , Microambiente Tumoral , Células A549 , Antineoplásicos/farmacología , Materiales Biocompatibles , Línea Celular Tumoral , Movimiento Celular , Humanos , Microscopía Confocal , Invasividad Neoplásica , Porosidad , Andamios del Tejido
5.
AAPS J ; 20(2): 34, 2018 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-29476273

RESUMEN

Low accumulation in tumor sites and slow intracellular drug release remain as the obstacles for nanoparticles to achieve effective delivery of chemotherapeutic drugs. In this study, multifunctional micelles were designed to deliver doxorubicin (Dox) to tumor sites to provide more efficient therapy against hepatic carcinoma. The micelles were based on pH-responsive carboxymethyl chitosan (CMCh) modified with a reactive oxygen species (ROS)-responsive segment phenylboronic acid pinacol ester (BAPE) and an active targeted ligand CD147 monoclonal antibody. The Dox-loaded micelles provided rapid and complete drug release in pH 5.3 incubation conditions with 1 mM H2O2. In addition, an in vitro cell uptake study revealed that CD147 modification significantly enhanced cellular internalization due to the high affinity to CD147 receptors, which are overexpressed on tumor cells. An in vivo study revealed that CD147-modified micellar formulations exhibited high accumulation in tumor sites and markedly enhanced antiproliferation effects with fewer side effects than other formulations. In conclusion, this CD147 receptor targeted delivery system with ROS/pH dual sensitivity provides a promising strategy for the treatment of hepatic carcinoma.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Carcinoma Hepatocelular/tratamiento farmacológico , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Neoplasias Hepáticas/tratamiento farmacológico , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/metabolismo , Basigina/inmunología , Línea Celular Tumoral , Preparaciones de Acción Retardada/administración & dosificación , Femenino , Humanos , Concentración de Iones de Hidrógeno , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Micelas , Nanopartículas/química , Nanopartículas/metabolismo , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
6.
J Control Release ; 268: 198-211, 2017 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-29061511

RESUMEN

Malignant proliferation and metastasis in non-small cell lung carcinoma (NSCLC) are great challenges for effective clinical treatment through conventional chemotherapy. The combinational therapy strategy of RNA interfering (RNAi) technology and chemotherapeutic agents have been reported to be promising for effective cancer therapy. In this study, based on multifunctional nanoparticles (NPs), the simultaneous delivery of etoposide (ETP) and anti-Enhancer of Zeste Homologue 2 (EZH2) siRNA for the effective treatment of orthotopic lung tumor was achieved. The NPs exhibited pH/redox dual sensitivity verified by particle size changes, morphological changes, and in vitro release of drugs. Confocal microscopy analysis confirmed that the NPs exhibited endosomal escape property and on-demand intracellular drug release behavior, which can protect siRNA from degradation and facilitate the chemotherapeutic effect respectively. In vitro tumor cell motility study demonstrated that EZH2 siRNA loaded in NPs can decrease the migration and invasion capabilities of tumor cells by downregulating the expression of EZH2 mRNA and protein. In particular, an antiproliferation study revealed that the co-delivery of siRNA and ETP in the multifunctional NPs can induce a synergistic therapeutic effect on NSCLC. In vivo targeting evaluation showed that cRGDyC-PEG modification on NPs exhibited a low distribution in normal organs and an obvious accumulation in orthotopic lung tumor. Furthermore, targeted NPs co-delivering siRNA and ETP showed superior inhibition on tumor growth and metastasis and produced minimal systemic toxicity. These findings indicated that multifunctional NPs can be utilized as a co-delivery system, and that the combination of EZH2 siRNA and ETP can effectively treat NSCLC.


Asunto(s)
Antineoplásicos Fitogénicos/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Proteína Potenciadora del Homólogo Zeste 2/genética , Etopósido/administración & dosificación , Nanopartículas/administración & dosificación , ARN Interferente Pequeño/administración & dosificación , Células A549 , Animales , Antineoplásicos Fitogénicos/química , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Ciclo Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Terapia Combinada , Liberación de Fármacos , Etopósido/química , Femenino , Humanos , Ratones Desnudos , Nanopartículas/química , Polímeros/administración & dosificación , Polímeros/química , ARN Interferente Pequeño/química
7.
Am J Physiol Cell Physiol ; 313(5): C567-C574, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-28814403

RESUMEN

Oxidized low-density lipoprotein (oxLDL) accumulates early in atherosclerotic lesions and plays an important role in the progressive formation of atherosclerotic plaques. Endothelial derived microparticles (EMPs) form a heterogeneous population of <1-µm particles that shed from endothelial membranes upon activation. While EMPs are shown to be involved in atherosclerotic pathophysiology and progression, there is no report regarding the relationship between oxLDL and EMPs. In this study, we aim to determine the influence of oxLDL on endothelial microparticle release and the subsequent regulation of the endothelial activation. EMPs were collected from the medium of human umbilical vein endothelial cells (HUVECs) treated with oxLDL or PBS as control. We find that oxLDL increases the release of EMPs containing intercellular adhesion molecule 1 (ICAM-1) but not vascular cell adhesion molecule 1 (VCAM-1). Confocal microscopy analysis further demonstrates that these EMPs interact with endothelial cells and increase the expression of ICAM-1 in HUVECs. The fact that injecting oxLDL-induced EMPs via the tail vein of ICR mice augments ICAM-1 expression on aortic endothelial cells confirms our results in vivo. Finally, oxLDL-induced EMPs from HUVECs increase the adhesion of monocytes to endothelial cells as determined by the adhesion assay. Our study suggests that oxLDL may augment the release of EMPs harboring increased levels of ICAM-1 that can be transferred to endothelial cells elsewhere. This leads to increased monocyte recruitment in other regions where oxLDL accumulation was initially more limited. EMPs may therefore serve as the mediator that propagates oxLDL-induced endothelial inflammation.


Asunto(s)
Micropartículas Derivadas de Células/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Molécula 1 de Adhesión Intercelular/biosíntesis , Lipoproteínas LDL/farmacología , Monocitos/metabolismo , Animales , Aterosclerosis/metabolismo , Adhesión Celular/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Ratones Endogámicos ICR , Monocitos/efectos de los fármacos
8.
Int J Nanomedicine ; 12: 4241-4256, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28652730

RESUMEN

Physicochemical properties, including particle size, zeta potential, and drug release behavior, affect targeting efficiency, cellular uptake, and antitumor effect of nanocarriers in a formulated drug-delivery system. In this study, a novel stepwise pH-responsive nanodrug delivery system was developed to efficiently deliver and significantly promote the therapeutic effect of doxorubicin (DOX). The system comprised dimethylmaleic acid-chitosan-urocanic acid and elicited stepwise responses to extracellular and intracellular pH. The nanoparticles (NPs), which possessed negative surface charge under physiological conditions and an appropriate nanosize, exhibited advantageous stability during blood circulation and enhanced accumulation in tumor sites via enhanced permeability and retention effect. The tumor cellular uptake of DOX-loaded NPs was significantly promoted by the first-step pH response, wherein surface charge reversion of NPs from negative to positive was triggered by the slightly acidic tumor extracellular environment. After internalization into tumor cells, the second-step pH response in endo/lysosome acidic environment elicited the on-demand intracellular release of DOX from NPs, thereby increasing cytotoxicity against tumor cells. Furthermore, stepwise pH-responsive NPs showed enhanced antiproliferation effect and reduced systemic side effect in vivo. Hence, the stepwise pH-responsive NPs provide a promising strategy for efficient delivery of antitumor agents.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/administración & dosificación , Animales , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Línea Celular Tumoral , Quitosano/química , Doxorrubicina/química , Doxorrubicina/farmacocinética , Portadores de Fármacos/química , Evaluación Preclínica de Medicamentos/métodos , Liberación de Fármacos , Femenino , Concentración de Iones de Hidrógeno , Malonatos/química , Ratones Endogámicos BALB C , Nanopartículas/química , Tamaño de la Partícula , Distribución Tisular , Ácido Urocánico/química
9.
J Biomed Mater Res B Appl Biomater ; 105(7): 2093-2106, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-27405391

RESUMEN

P-glycoprotein (P-gp) plays an importantrole in multidrug resistance (MDR), proved to be one of the major obstacles in cancer chemotherapy. Cationic polymers could specifically deliver siRNA to tumor cells and thus reverse MDR by the downregulation of P-gp. In this study, a triblock copolymer micelle was prepared based on the polymer of N-succinyl-chitosan-poly-l-lysine-palmitic acid (NSC-PLL-PA) to deliver siRNA-P-gp (siRNA-micelle) or doxorubicin (Dox-micelle). The resulting micelle exhibited an efficient binding ability for siRNA and high encapsulation efficiency for Dox, with an average particle size of ∼170 nm. siRNA-micelle and Dox-micellewere instable at low pH, thereby enhancing tumor accumulation and intracellular release of the encapsulated siRNA and Dox. siRNA-micelle micelles could enhance the knockdown efficacy of siRNA by improving the transfection efficiency, downregulating P-gp expression, and passing the drug efflux transporters, thereby improving the therapeutic effects of Dox-micelle. However, P-gp could transfer from HepG2/ADM to HepG2 cells independent of the expression of mdr1, and the acquired resistance could permit tumor cells to survive and develop intrinsic P-gp-mediated resistance, thereby limiting the desired efficiency of chemotherapeutics. This study demonstrated the effectiveness of siRNA-micelle for tumor-targeted delivery, MDR reversal, and provided an effective strategy for the treatment of cancers that develop MDR. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2093-2106, 2017.


Asunto(s)
Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos/métodos , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Micelas , Proteínas de Neoplasias , Neoplasias , ARN Interferente Pequeño , Subfamilia B de Transportador de Casetes de Unión a ATP/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Múltiples Medicamentos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Células Hep G2 , Humanos , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias/terapia , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología
10.
J Biomed Mater Res B Appl Biomater ; 105(5): 1114-1125, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-27008163

RESUMEN

The development of effective and stable carriers of small interfering RNA (siRNA) is important for treating cancer with multidrug resistance (MDR). We developed a new gene and drug co-delivery system and checked its characteristics. Low-density lipoprotein (LDL) was coupled with N-succinyl chitosan (NSC) Lipoic acid (LA) micelles and co-delivered MDR1 siRNA and paclitaxel (PTX-siRNA/LDL-NSC-LA) to enhance antitumor effects by silencing the MDR gene of tumors (Li et al., Adv Mater 2014;26:8217-8224). In our study, we developed a new type of containing paclitaxel-loaded micelles and siRNA-loaded LDL nanoparticle. This "binary polymer" is pH and reduction dual-sensitive core-crosslinked micelles. PTX-siRNA/LDL-NSC-LA had an average particle size of (171.6 ± 6.42) nm, entrapment efficiency of (93.92 ± 1.06) %, and drug-loading amount of (12.35% ± 0.87) %. In vitro, MCF-7 cells, high expressed LDL receptor, were more sensitive to this delivery system than to taxol® and cell activity was inhibited significantly. Fluorescence microscopy showed that PTX-siRNA/LDL-NSC-LA was uptaken very conveniently and played a key role in antitumor activity. PTX-siRNA/LDL-NSC-LA protected the siRNA from degradation by macrophage phagocytosis and evidently down-regulated the level of mdr1 mRNA as well as the expression of P-gp. We tested the target ability of PTX-siRNA/LDL-NSC-LA in vivo in tumor-bearing nude mice. Results showed that this system could directly deliver siRNA and PTX to cancer cells. Thus, new co-delivering siRNA and antitumor drugs should be explored for solving MDR in cancer. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1114-1125, 2017.


Asunto(s)
Quitosano , Técnicas de Transferencia de Gen , Lipoproteínas LDL , Micelas , Proteínas de Neoplasias , Neoplasias Experimentales , Paclitaxel/farmacología , ARN Interferente Pequeño , Ácido Tióctico , Subfamilia B de Transportador de Casetes de Unión a ATP/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP/biosíntesis , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Animales , Quitosano/química , Quitosano/farmacología , Femenino , Humanos , Lipoproteínas LDL/química , Lipoproteínas LDL/farmacología , Células MCF-7 , Ratones , Ratones Desnudos , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Neoplasias Experimentales/genética , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Neoplasias Experimentales/terapia , ARN Interferente Pequeño/biosíntesis , ARN Interferente Pequeño/genética , Ácido Tióctico/química , Ácido Tióctico/farmacología , Ensayos Antitumor por Modelo de Xenoinjerto
11.
ACS Appl Mater Interfaces ; 8(47): 32146-32158, 2016 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-27933846

RESUMEN

The efficient delivery of antitumor agents to tumor sites faces numerous obstacles, such as poor cellular uptake and slow intracellular drug release. In this regard, smart nanoparticles (NPs) that respond to the unique microenvironment of tumor tissues have been widely used for drug delivery. In this study, novel charge-reversal and reduction-responsive histidine-grafted chitosan-lipoic acid NPs (HCSL-NPs) were selected for efficient therapy of breast cancer by enhancing cell internalization and intracellular pH- and reduction-triggered doxorubicin (DOX) release. The surface charge of HCSL-NPs presented as negative at physiological pH and reversed to positive at the extracellular and intracellular pH of the tumor. In vitro release investigation revealed that DOX/HCSL-NPs demonstrated a sustained drug release under the physiological condition, whereas rapid DOX release was triggered by both endolysosome pH and high-concentration reducing glutathione (GSH). These NPs exhibited enhanced internalization at extracellular pH, rapid intracellular drug release, and improved cytotoxicity against 4T1 cells in vitro. Excellent tumor penetrating efficacy was also found in 4T1 tumor spheroids and solid tumor slices. In vivo experiments demonstrated that HCSL-NPs exhibited excellent tumor-targeting ability in tumor tissues as well as excellent antitumor efficacy and low systemic toxicity in breast tumor-bearing BALB/c mice. These results indicated that the novel charge-reversal and reduction-responsive HCSL-NPs have great potential for targeted and efficient delivery of chemotherapeutic drugs in cancer treatments.


Asunto(s)
Nanopartículas , Animales , Doxorrubicina , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Humanos , Concentración de Iones de Hidrógeno , Ratones , Ratones Endogámicos BALB C
12.
J Am Heart Assoc ; 5(10)2016 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-27792649

RESUMEN

BACKGROUND: A new mechanism for intercellular communication has recently emerged that involves intercellular transfer of extracellular vesicles (EVs). Several studies have indicated that EVs may play a potential role in cell-to-cell communication between macrophage foam cells and vascular smooth muscle cells (VSMCs) in atherosclerotic lesion. METHODS AND RESULTS: This study involved the comparison of circulating EVs from atherosclerotic patients and control participants. The results showed that the circulation of the patients contained more leukocyte-derived EVs and that these EVs promoted more VSMC adhesion and migration than those of healthy participants. We then established a macrophage foam cell model and characterized the EVs from the macrophages. We used flow cytometric analyses and cell migration and adhesion assays and determined that the foam cells generated more EVs than the normal macrophages and that the foam cell-derived EVs were capable of promoting increased levels of VSMC migration and adhesion. Furthermore, we performed a proteomic analysis of the EVs. The data showed that the foam cell-derived EVs may promote VSMC adhesion and migration by regulating the actin cytoskeleton and focal adhesion pathways. In addition, Western blotting revealed that foam cell-derived EVs could promote the phosphorylation of ERK and Akt in VSMCs in a time-dependent manner. We also found that foam cell-derived EVs could enter the VSMCs and transfer integrins to the surface of these cells. CONCLUSIONS: The data in our present study provide the first evidence that EVs from foam cells could promote VSMC migration and adhesion, which may be mediated by the integration of EVs into VSMCs and the subsequent downstream activation of ERK and Akt.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Aterosclerosis/metabolismo , Adhesión Celular , Movimiento Celular , Vesículas Extracelulares/metabolismo , Células Espumosas/metabolismo , Músculo Liso Vascular/citología , Miocitos del Músculo Liso , Anciano , Western Blotting , Estudios de Casos y Controles , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Citometría de Flujo , Humanos , Integrinas/metabolismo , Macrófagos/metabolismo , Masculino , Persona de Mediana Edad , Fosforilación , Proteómica , Proteínas Proto-Oncogénicas c-akt/metabolismo
13.
Int J Pharm ; 511(2): 728-40, 2016 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-27484835

RESUMEN

Internal stimuli, such as intracellular lysosomal pH, enzyme, redox and reduction, can be applied to improve biological specificity of chemotherapeutic drugs for cancer therapy. Thus, functionalized copolymers based on their response to specific microenvironment of tumor regions have been designed as smart drug vesicles for enhanced anti-cancer efficiency and reduced side effects. Herein, we reported dually pH/reduction-responsive novel micelles based on self-assembly of carboxymethyl chitosan-cysteamine-N-acetyl histidine (CMCH-SS-NA) and doxorubicin (DOX). The tailor-made dually responsive micelles demonstrated favorable stability in normal physiological environment and triggered rapid drug release in acidic and/or reduction environment. Additionally, the nanocarriers responded to the intracellular environment in an ultra-fast manner within several minutes, which led to the pinpointed release of DOX in tumor cells effectively and ensured higher DOX concentrations within tumor areas with the aid of targeted delivery, thereby leading to enhanced tumor ablation. Thus, this approach with sharp drug release behavior represented a versatile strategy to provide a promising paradigm for cancer therapy.


Asunto(s)
Doxorrubicina/farmacología , Doxorrubicina/farmacocinética , Micelas , Microambiente Tumoral/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Quitosano/análogos & derivados , Quitosano/química , Cisteamina/química , Doxorrubicina/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Liberación de Fármacos , Femenino , Histidina/química , Concentración de Iones de Hidrógeno , Hígado/metabolismo , Ratones , Oxidación-Reducción , Ratas , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Exp Ther Med ; 11(4): 1481-1486, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27073469

RESUMEN

The present study aimed to investigate the time course of changes in microparticles (MPs) in patients with ST-segment elevation myocardial infarction (STEMI) that underwent percutaneous transluminal coronary intervention (PCI). A total of 24 STEMI patients undergoing primary PCI were enrolled, and circulating MPs were detected immediately prior to and after PCI, and at 4, 24 and 48 h post-PCI. Standard Megamix beads, based measurement protocols, were employed to measure MPs of different cell origin, including endothelial MPs (EMPs), platelet MPs (PMPs) and leukocyte-derived MPs (LMPs), which were identified by CD144, CD41 and CD45, respectively. The results indicated that PMP levels were evidently elevated immediately after PCI, and reached a maximum level at 48 h. In addition, LMP and EMP levels were significantly decreased immediately after the PCI, and then increased gradually with time. The total quantity of the three aforementioned MP types increased gradually at 48 h following PCI. Furthermore, coronary angiographic Gensini scores were significantly positively correlated with the level of PMPs (r2=0.42; P=0.0006). Log-normalized high sensitivity-C-reactive-protein was also significantly correlated with LMPs (r2=0.86; P<0.01). In conclusion, the time course of the changes in circulating MPs of different cell origin, provided information on possible functions of different MPs in STEMI.

15.
Sci Rep ; 6: 23859, 2016 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-27030638

RESUMEN

Co-delivery of chemotherapeutics and siRNA with different mechanisms in a single system is a promising strategy for effective cancer therapy with synergistic effects. In this study, a triblock copolymer micelle was prepared based on the polymer of N-succinyl chitosan-poly-L-lysine-palmitic acid (NSC-PLL-PA) to co-deliver doxorubicin (Dox) and siRNA-P-glycoprotein (P-gp) (Dox-siRNA-micelle). Dox-siRNA-micelle was unstable in pH 5.3 medium than in pH 7.4 medium, which corresponded with the in vitro rapid release of Dox and siRNA in acidic environments. The antitumor efficacy of Dox-siRNA-micelle in vitro significantly increased, especially in HepG2/ADM cells, which was due to the downregulation of P-gp. Moreover, almost all the Dox-siRNA-micelles accumulated in the tumor region beyond 24 h post-injection, and the co-delivery system significantly inhibited tumor growth with synergistic effects in vivo. This study demonstrated the effectiveness of Dox-siRNA-micelles in tumor-targeting and MDR reversal, and provided a promising strategy to develop a co-delivery system with synergistic effects for combined cancer therapy.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/antagonistas & inhibidores , Antibióticos Antineoplásicos/farmacología , Terapia Combinada/métodos , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos/métodos , Neoplasias Hepáticas/terapia , ARN Interferente Pequeño/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Liberación de Fármacos , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Múltiples Medicamentos/genética , Resistencia a Antineoplásicos/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Femenino , Expresión Génica , Células Hep G2 , Humanos , Concentración de Iones de Hidrógeno , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones , Ratones Desnudos , Micelas , ARN Interferente Pequeño/metabolismo , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Int J Nanomedicine ; 11: 325-36, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26855571

RESUMEN

In this study, harmine liposomes (HM-lip) were prepared through the thin-film hydration-pH-gradient method and then coated with N-trimethyl chitosan (TMC). Particle size, zeta potential, entrapment efficiency, and in vitro release of HM-lip and TMC-coated harmine liposomes (TMC-HM-lip) were also determined. Sprague Dawley rats were further used to investigate the pharmacokinetics in vivo. Retention behavior in mouse gastrointestinal tract (GIT) was studied through high-performance liquid chromatography and near-infrared imaging. Degradation was further evaluated through incubation with Caco-2 cell homogenates, and a Caco-2 monolayer cell model was used to investigate the uptake and transport of drugs. HM-lip and TMC-HM-lip with particle size of 150-170 nm, an entrapment efficiency of about 81%, and a zeta potential of negative and positive, respectively, were prepared. The release of HM from HM-lip and TMC-HM-lip was slower than that from HM solution and was sensitive to pH. TMC-HM-lip exhibited higher oral bioavailability and had prolonged retention time in GIT. HM-lip and TMC-HM-lip could also protect HM against degradation in Caco-2 cell homogenates. The uptake amount of TMC-HM-lip was higher than that of HM and HM-lip. TMC-HM-lip further demonstrated higher apparent permeability coefficient (P(app)) from the apical to the basolateral side than HM and HM-lip because of its higher uptake and capability to open tight junctions in the cell monolayers. TMC-HM-lip can prolong the retention time in the GIT, protect HM against enzyme degradation, and improve transport across Caco-2 cell monolayers, thus enhancing the oral bioavailability of HM.


Asunto(s)
Quitosano/química , Tracto Gastrointestinal/efectos de los fármacos , Harmina/metabolismo , Liposomas/química , Administración Oral , Animales , Disponibilidad Biológica , Células CACO-2 , Permeabilidad de la Membrana Celular , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Portadores de Fármacos/química , Tracto Gastrointestinal/citología , Tracto Gastrointestinal/metabolismo , Humanos , Técnicas In Vitro , Liposomas/administración & dosificación , Ratones , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley
17.
Yao Xue Xue Bao ; 51(4): 642-9, 2016 04.
Artículo en Chino | MEDLINE | ID: mdl-29860751

RESUMEN

cRGD-carboxymethyl chitosan-palmitic acid (cRGD-CMCh-PA) was synthesized and a pH- sensitive paclitaxel-loaded cRGD-CMCh-PA micelles(PTX-cRGD-CMCh-PA) was prepared with the film dispersion method; related substances were characterized by FT-IR and (1)H NMR. PTX-cRGD-CMCh-PA micelles were studied with the particle size distribution, zeta potential, morphology and release behavior in vitro was investigated by the method of equilibrium dialysis. In vitro cytotoxicity of different formulations on A549 cells was tested by MTT assay. The uptake process of micelles was explored using confocal microscopy and a live cell station was used to observe the dynamic phagocytosis. The subcutaneous and orthotropic tumor models were built to study the distribution of Di R-labeled micelles by near-infrared fluorescence(NIR) imaging system. The FT-IR spectra and (1)H NMR spectra confirmed the successful conjugation of cRGD-CMCh-PA polymer and the degree of carboxymethyl and the palmitic acid grafted on chitosan were 45.0% and 15.0%. PTX-cRGD-CMCh-PA micelles were prepared with particle size of(162.9 ± 1.5) nm, zeta potential of +26.3 m V and encapsulation efficiency and the drug loading of 99.67% and 28.5%, respectively. The micelles released slowly in pH 7.4 whose release curves were accorded with the Higuchi equation; they had an initial burst effect in second hours and showed a pH sensitive release behavior in pH 5.3. The IC(50) of PXT-CMCh-PA and PTX-cRGD-CMCh-PA were 2.077 µg·mL(-1) and 0.876 µg·mL(-1), respectively. The cells uptake process of micelles in A549 cells revealed that the micelles were mainly co-located with lysosome and PTX-cRGD-CMCh- PA showed much better targeting effect. The NIR fluorescence imaging results showed that the micelles had a good targeting effect on both subcutaneous and orthotropic tumors. In this study, a novel copolymer cRGD- CMCh-PA was synthesized with a sustained and pH-dependent drug release activity which would potentially become a new carrier for hydrophobic drugs.


Asunto(s)
Quitosano/análogos & derivados , Portadores de Fármacos/química , Oligopéptidos/química , Paclitaxel/administración & dosificación , Ácido Palmítico/química , Células A549 , Antineoplásicos Fitogénicos/administración & dosificación , Quitosano/química , Liberación de Fármacos , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Micelas , Tamaño de la Partícula , Polímeros , Espectroscopía Infrarroja por Transformada de Fourier
18.
Sci Rep ; 5: 17904, 2015 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-26639052

RESUMEN

An antibody that specifically interacts with an antigen could be applied to an active targeting delivery system. In this study, CD147 antibody was coupled with α-hed chitosan nanoparticles (α-Hed-CS-NPs). α-Hed-CS-CD147-NPs were round and spherical in shape, with an average particle size of 148.23 ± 1.75 nm. The half-maximum inhibiting concentration (IC50) of α-Hed-CS-CD147-NPs in human liver cancer cell lines HepG2 and SMMC-7721 was lower than that of free α-Hed and α-Hed-CS-NPs. α-Hed-induced cell death was mainly triggered by apoptosis. The increase in intracellular accumulation of α-Hed-CS-CD147-NPs was also related to CD147-mediated internalization through the Caveolae-dependent pathway and lysosomal escape. The higher targeting antitumor efficacy of α-Hed-CS-CD147-NPs than that α-Hed-CS-NPs was attributed to its stronger fluorescence intensity in the tumor site in nude mice.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antineoplásicos/farmacología , Basigina/inmunología , Quitosano/química , Endocitosis/efectos de los fármacos , Neoplasias Hepáticas/patología , Nanopartículas/química , Ácido Oleanólico/análogos & derivados , Saponinas/farmacología , Animales , Anexina A5/metabolismo , Apoptosis/efectos de los fármacos , Citometría de Flujo , Fluorescencia , Células Hep G2 , Humanos , Imagenología Tridimensional , Espacio Intracelular/metabolismo , Ratones Desnudos , Microscopía Confocal , Nanopartículas/ultraestructura , Ácido Oleanólico/síntesis química , Ácido Oleanólico/química , Ácido Oleanólico/farmacología , Tamaño de la Partícula , Propidio/metabolismo , Saponinas/síntesis química , Saponinas/química , Espectroscopía Infrarroja por Transformada de Fourier , Espectroscopía Infrarroja Corta , Fracciones Subcelulares/metabolismo
19.
Biomarkers ; 20(6-7): 429-35, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26554436

RESUMEN

Endothelial microparticle (EMP) is a biomarker for endothelial dysfunction. The aim of this study is to investigate the utility of EMP in evaluating coronary intermediate lesions. Participants included 49 patients with coronary intermediate lesions and 24 subjects with normal coronary arteries. Among these subjects, 28 patients accepted fractional flow reserve (FFR). Results showed that level of EMP was significantly higher in the intermediate lesion group. No correlation was found between EMP and FFR value, suggesting that circulating EMP is a systemic marker rather than a focal one.


Asunto(s)
Micropartículas Derivadas de Células/metabolismo , Enfermedad de la Arteria Coronaria/fisiopatología , Endotelina-1/metabolismo , Reserva del Flujo Fraccional Miocárdico , Óxido Nítrico Sintasa de Tipo III/metabolismo , Óxido Nítrico/metabolismo , Anciano , Biomarcadores/sangre , Biomarcadores/metabolismo , Distribución de Chi-Cuadrado , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/metabolismo , Endotelina-1/sangre , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Óxido Nítrico/sangre , Óxido Nítrico Sintasa de Tipo III/sangre
20.
Diab Vasc Dis Res ; 12(6): 467-70, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26246491

RESUMEN

The study was designed to discover the biological function of endotheliocyte-derived microparticles in diabetes condition. A quantitative shotgun proteomics methodology was performed to study the proteome of these high-glucose-activated endothelial microparticles. A total of 1428 proteins were identified, containing 1421 and 1423 proteins in control and high-glucose groups, respectively. According to the ExoCarta database, 669 proteins have previously been identified in microparticles. The proteins associated with disease were identified in this study, and notably, 30 proteins have been reported to be associated with Alzheimer's disease, including amyloid beta A4 protein. Besides, the peptide abundance of amyloid beta A4 protein from control group was much less than that from high-glucose group. In conclusion, this work revealed the proteome of endothelial microparticles in mimic diabetes condition and provided a new proteomic evidence for Alzheimer's disease to be counted as the type 3 diabetes.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Micropartículas Derivadas de Células/metabolismo , Proteoma/metabolismo , Proteómica , Células Cultivadas , Glucosa/metabolismo , Humanos , Proteómica/métodos
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