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1.
Acta Radiol ; 63(10): 1433-1440, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34463146

RESUMEN

BACKGROUND: Radiation therapy is regarded as an effective treatment for early ovarian cancer (OC). However, due to radiation resistance caused by DNA double-strand breaks (DSBs) and angiogenesis, the efficacy of radiotherapy for advanced OC is limited and controversial. PURPOSE: To explore whether ultrasound-stimulated microbubbles (USMBs) can enhance the radiosensitivity of OC. MATERIAL AND METHODS: OC cells (ES-2) were respectively irradiated with 5-Gy and 10-Gy radiation doses with or without exposure to USMB. Methyl thiazolyltetrazolium (MTT) and colony-formation assays were conducted to detect the viability and proliferation of ES-2 cells after USMBs and ionizing radiation (IR) treatment. Immunofluorescence assays were conducted to examine levels of gamma-H2A histone family member X (γ-H2AX), an indicator for DSBs. Flow cytometry analyses were carried out to assess the apoptosis of ES-2 cells. The angiogenic activity of human umbilical vein endothelial cells (HUVECs) was measured by tube formation assays. RESULTS: USMBs enhanced IR-induced suppressive effect on the viability and proliferation of OC cells. The protein levels of phosphorylated γ-H2AX and CHK1 were significantly upregulated after IR treatment and further enhanced by USMBs. In addition, USMBs enhanced the promotion of IR-mediated OC cell apoptosis. The inhibitory effect of IR on angiogenesis was further enhanced by USMBs, and protein levels of AT1R, VEGFA, and EGFR were downregulated by IR in a dose-dependent way and then enhanced by USMB treatment in HUVECs. CONCLUSIONS: USMB exposure significantly enhances the radiosensitivity of OC by suppressing cell proliferation, promoting OC cell apoptosis, and inhibiting angiogenesis.


Asunto(s)
Microburbujas , Neoplasias Ováricas , Apoptosis/efectos de la radiación , Línea Celular Tumoral , ADN/farmacología , Células Endoteliales/metabolismo , Receptores ErbB/metabolismo , Receptores ErbB/farmacología , Femenino , Histonas/metabolismo , Histonas/farmacología , Humanos , Neoplasias Ováricas/radioterapia , Tolerancia a Radiación
2.
Pharmaceutics ; 13(8)2021 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-34452166

RESUMEN

Cancer stem-like cells (CSLCs) have been considered to be one of the main problems in tumor treatment owing to high tumorigenicity and chemotherapy resistance. In this study, we synthesized a novel mitochondria-target derivate, triphentlphosphonium-resveratrol (TPP-Res), and simultaneously encapsulated it with doxorubicin (Dox) in pH-sensitive liposomes (PSL (Dox/TPP-Res)), to reverse chemotherapeutic resistance of CSLCs. PSL (Dox/TPP-Res) was approximately 165 nm in size with high encapsulation efficiency for both Dox and TPP-Res. Cytotoxicity assay showed that the optimal synergistic effect was the drug ratio of 1:1 for TPP-Res and Dox. Cellular uptake and intracellular trafficking assay indicated that PSL (Dox/TPP-Res) could release drugs in acidic endosomes, followed by mitochondrial targeting of TPP-Res and nucleus transports for Dox. The mechanisms for reversing the resistance in CSLCs were mainly attributed to a synergistic effect for reduction of mitochondrial membrane potential, activation of caspase cascade reaction, reduction of ATP level and suppression of the Wnt/ß-catenin pathway. Further, in vivo assay results demonstrated that the constructed liposomes could efficiently accumulate in the tumor region and possess excellent antineoplastic activity in an orthotopic xenograft tumor model with no evident systemic toxicity. The above experimental results determined that PSL (Dox/TPP-Res) provides a new method for the treatment of heterogenecity tumors.

3.
J Pain Res ; 14: 1667-1673, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34140803

RESUMEN

BACKGROUND: Temporomandibular joint disorder (TMD) affects millions of people. It is unclear if low intensity ultrasound (US) is effective to treat TMD. METHODS: A total of 160 patients with TMD were enrolled in this study. The subjects were randomized into two groups to receive US therapy or no therapy. Patients in the US group were given US therapy once a day for 5 days per week for 2 consecutive weeks. Before and 4 weeks and 6 months after the treatments, the patients were assessed for pain using visual analog scale (VAS) and the maximum pain-free inter-incisal distance (IID). In addition, mandibular movement (MM), jaw noise (JN), disability index (DI) and craniomandibular index (CMI) were also assessed. RESULTS: Compared with the patients before the therapy, VAS, IID, MM, JN, DI and CMI in the US group were significantly improved 4 weeks and 6 months after therapy. However, 6 months after the therapy, US group had a recurrence rate of 2.63%. CONCLUSION: US therapy can significantly reduce the pain, and improve the functionality of the temporomandibular joint and mouth opening limit for TMD patients, and is therefore recommended for TMD patients.

4.
World Neurosurg ; 2020 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-33217592

RESUMEN

The paper uses an optimized denoising algorithm, combined with spiral CT coronary angiography (CCTA) in conjunction with carotid ultrasound, serological markers relevance for the assessment of coronary artery disease was analysed early T2DM and coronary heart disease (CHD) in patients with coronary and carotid artery disease to provide diagnostic evidence. Papers selected from January 2017 to December 2019 in hospital diagnosed 95 patients CHD, CHD were divided into three groups (n = 45) and T2DM with CHD group (n depending on whether T2DM disease = 50), were compared coronary arteries, the degree of carotid lesions, high-sensitivity C- reactive protein (hsC-RP) and the difference of FFA. CCTA display, combined with CHD of T2DM in double-vessel coronary artery disease and three main right coronary artery, left circumflex artery plaques appear more CHD combined group of T2DM, and three double-vessel coronary disease carotid plaque compared with the number of single-vessel disease and more. Spearman correlation analysis showed, hsC-RP positively correlated with FFA, hsC-RP and coronary artery lesion count was positively correlated. CCTA display, T2DM with CHD in coronary plaque with soft plaque and mixed plaque mainly extensive coronary artery disease, carotid artery ultrasound prompted the more peripheral vascular plaque number, the more the number of diseased vessels, the more severe the disease. Joint CCTA Clinically, carotid ultrasound and hsC-RP, FFA level detection can improve the rate of diagnosis of T2DM with CHD, reduce false positives, should be widely applied.

5.
Biomaterials ; 162: 47-59, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29432988

RESUMEN

Despite the extracellular barriers for siRNA delivery have been overcome by utilizing advanced nanoparticle delivery systems, the key intracellular barriers after internalization including efficient disassembly of siRNA and endosomal escape still remains challenging. To address the issues, we developed a unique pH- and redox potential-responsive polyplex delivery system based on the copolymer of mPEG-b-PLA-PHis-ssPEI1.8 k, which is composed of a pH-responsive copolymer of PEG-b-PLA-PHis (Mw 5 k) and a branched PEI (Mw1.8 k) linked with redox cleavable disulfide bond. The copolymer showed excellent siRNA complexation and protection abilities against endogenous substances at the relatively low N/P ratio of 6. The siRNA release from the polyplexes (N/P 6) was markedly increased from 13.62% to 58.67% under conditions simulating the endosomal microenvironment. Fluorescence resonance energy transfer (FRET) test also indicated a higher disassembly extent of siRNA from the copolymer. The accelerated siRNA release from the polyplexes was markedly restrained when the N/P ratio was raised above 10 due to the increasing of electrostatic interactions. The efficient endosomal escape of siRNA after internalization was confirmed by confocal microscopy, which was attributed to the cleavaged PEI chains inducing membrane destabilization, the "proton sponge effect" of PHis and PEI as well as the relative small size of after disassembly. The enhanced disassembly and endosomal escape were elucidated as the leading cause for polyplexes (N/P 6) showed more efficient Bcl-2 silencing (85.45%) than those polyplexes with higher N/P ratios (N/P 10 and 15). In vivo results further demonstrated that polyplexes (N/P 6) delivery of siBcl-2 significantly inhibited the MCF-7 breast tumor growth as compared to its counterparts. The incorporation of convertible non-electrical interactions at a balance with electrostatic interactions in complexation siRNA has been demonstrated as an effective strategy to achieve efficient disassembly from stable polyplexes. Moreover, polyplexes equipped with the enhanced disassembly and endosomal escape provides a new potential way to tackle the intracellular delivery bottleneck for siRNA delivery.


Asunto(s)
Endosomas/química , Polímeros/química , ARN Interferente Pequeño/química , Animales , Western Blotting , Femenino , Humanos , Concentración de Iones de Hidrógeno , Células MCF-7 , Ratones , Ratones Desnudos , Microscopía Confocal , Oxidación-Reducción , ARN Interferente Pequeño/administración & dosificación
6.
Colloids Surf B Biointerfaces ; 140: 176-184, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26764099

RESUMEN

Even though the Poly(l-histidine) (PHis) based copolymers have been well studied, the effect of the chemically substituted l-histidine on the physio-chemical and biological properties of the micelles has never been elucidated to date. To address this issue, triblock copolymer of poly(ethylene glycol)-poly(D,L-lactide)-poly(2,4-dinitrophenol-L-histidine)(mPEG-b-PLA-b-DNP-PHis) with DNP group substituted to the saturated nitrogen of l-histidine were synthesized. The pH sensitive properties of the copolymer micelles were characterized using an acid-base titration method, fluorescene probe technique, DLS observation, in vitro drug release and cytotoxicity against MCF-7 cells under different pH conditions, respectively. The results suggest that mPEG-b-PLA-b-DNP-PHis copolymers showed similar micellar stability for DOX loaded micelles, increased particle size, and similar pH responsive properties with mPEG-b-PLA-b-PHis copolymers. The subcellular distribution observation demonstrated that mPEG-b-PLA-b-DNP-PHis micelles showed a slightly compromised endo-lysosmal escape of doxorubicin as compared to mPEG-b-PLA-b-PHis micelles. The mPEG-b-PLA-b-DNP-PHis micelles showed higher cellular uptake by MCF-7 cells than mPEG-b-PLA-b-PHis micelles due to the different uptake pathways. Effect of DNP substitution on the in vivo distribution of the copolymer micelles was studied using non-invasive near-infrared fluorescence (NIRF) imaging with mPEG-b-PLA-b-PHis micelles as control. The results indicate that the mPEG-b-PLA-b-DNP-PHis micelles showed a reduced passive targeting to the tumor due to the larger particle size. These results suggest that saturated nitrogen of PHis may serve as a valuable site for chemical modification of the PHis based copolymers because of the little effect on the pH responsive properties. However, selection of the substitution group needs to be considered due to the possible increase of micellar particle size of the micelles, leading to compromised passive targeting.


Asunto(s)
Histidina/química , Micelas , Polímeros/química , Animales , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Doxorrubicina/farmacocinética , Sistemas de Liberación de Medicamentos/métodos , Femenino , Humanos , Concentración de Iones de Hidrógeno , Células MCF-7 , Ratones Endogámicos BALB C , Ratones Desnudos , Microscopía Confocal , Tamaño de la Partícula , Poliésteres/química , Polietilenglicoles/química , Distribución Tisular
7.
Biomacromolecules ; 15(11): 4032-45, 2014 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-25308242

RESUMEN

Various poly(l-histidine) based amphiphilic copolymers have been developed for intracellular drug delivery due to the pH responsive properties and the escape from endolysosomal pathway. However, the pH induced reassembly of copolymer micelles and the assumed endolysosome membrane rupture during the copolymer facilitated endolysosomal escape have never been elucidated. To address these issues, a series of poly(ethylene glycol)-poly(d,l-lactide)-poly(l-histidine) (mPEG-PLA-PHis) with different degrees of polymerization of PLA and PHis block were synthesized. The self-assembly and reassembly behaviors of the copolymers were characterized using transmission electron microscopy (TEM), (1)H NMR, fluorescence probe technique, and dynamic light scattering (DLS). The copolymers self-assembled into micelles with PLA and unprotonated PHis blocks as hydrophobic core and PEG as hydrophilic shell at neutral pH. The changes in TEM images, (1)H NMR spectrum of PHis peak, pyrene fluorescene spectrum, and particle size as well as size distribution over the pH range from pH 8.5 to 4.5 suggest that the copolymer micelles reassembled into micelles with PLA as hydrophobic core and protonated PHis and PEG as hydrophilic shell under acidic environment. The pH induced reassembly triggered the incoporated doxorubicin (DOX) release, as indicated by the in vitro accelerated drug release and enhanced cytotoxicity. The integrity of endolysosome membrane during the copolymer facilitated DOX endolysosomal escape was observed by confocal laser scan microscopy (CLSM) and further evaluated by hemolysis test and calculation of the critical size of endolysosomal membrane. The results indicate that the endolysosomal membrane remained intact during the copolymer facilitated endolysosomal escape of DOX. It is more reasonable to ascribe the PHis based copolymer facilitation endolysosomal escape to the "proton sponge" hypothesis without rupturing the endolysosomal membrane.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Histidina/química , Líquido Intracelular/efectos de los fármacos , Micelas , Polímeros/química , Animales , Histidina/administración & dosificación , Histidina/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Líquido Intracelular/metabolismo , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Células MCF-7 , Masculino , Polímeros/administración & dosificación , Polímeros/metabolismo , Ratas , Ratas Sprague-Dawley
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