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1.
Pacing Clin Electrophysiol ; 46(12): 1635-1642, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37942981

RESUMO

OBJECTIVE: This study aimed to explore the roles of duration and burden of atrial high-rate episode (AHRE) on ischemic stroke in patients with pacemaker implantation. METHODS: Patients with pacemaker implantation for bradycardia from 2013 to 2017 were consecutively enrolled. Data such as gender, age, combined diseases, type of AF, left atrial size, left ventricular size, left ventricular ejection fraction, CHA2 DS2 -VASc score, and anticoagulants were collected. The burden and duration of AHRE based on different interval partition were also recorded in detail to evaluate the impacts on ischemic stroke. Cox regression analysis with time-dependent covariates was conducted. RESULTS: A total of 220 patients with AHRE were enrolled. The average follow-up time was 48.42 ± 17.20 months. Univariate regression analysis showed that diabetes (p = .024), high CHA2 DS2 -VASc score (≥ 2) (p = .021), long mean AHRE burden (p = .011), long maximal AHRE burden (p = .015), long AHRE duration lasting≥48 h (p = .001) or 24 h (p = .001) or 12 h (p = .005) were prone to ischemic stroke. Further multivariate regression analysis showed that long duration of AHRE (≥48 h) (HR 10.77; 95% CI 3.22-55.12; p = .030) were significantly correlated with stroke in patients with paroxysmal AF. There was no significant correlation between the type of AF and stroke (p = .927). CONCLUSION: The longer duration of AHRE (≥48 h) was more favorable in predicting ischemic stroke than high CHA2 DS2 -VASc score (≥2).


Assuntos
Fibrilação Atrial , AVC Isquêmico , Humanos , Medição de Risco , Fatores de Risco , Volume Sistólico , Função Ventricular Esquerda
2.
Odontology ; 106(3): 266-273, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29468332

RESUMO

The aims of this study were to reveal the usefulness of a newly developed method for measuring tongue volume (TV) and oral cavity capacity (OCC) and to assess the relationship between them. The tongue was coated with a contrast agent, and the TV and OCC were determined using cone-beam computed tomography (CBCT). We enrolled 20 adults who were scheduled to undergo CBCT to evaluate the relationship of the third molar roots to the alveolar nerve before molar extraction. Each participant's tongue was coated with a contrast agent, and CBCT of the tongue and oral cavity was performed. Using computer software, we evaluated reconstructed 3D images of the TV, oral cavity proper volume (OCPV), and OCC. The mean TV was 47.07 ± 7.08 cm3. The mean OCPV and OCC were 4.40 ± 2.78 cm3 and 51.47 ± 6.46 cm3, respectively. There was a significant correlation between TV and OCC (r = 0.920; p < 0.01) but not between TV and OCPV. The mean TV/OCC ratio was 91 ± 5%. The proposed method produced CBCT images that enabled effective measurement of TV and OCC. This simple method of measuring TV and OCC will be useful in the diagnosis on the tongues with abnormal size.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Boca/anatomia & histologia , Boca/diagnóstico por imagem , Língua/anatomia & histologia , Língua/diagnóstico por imagem , Adulto , Meios de Contraste , Feminino , Humanos , Imageamento Tridimensional , Masculino , Interpretação de Imagem Radiográfica Assistida por Computador
3.
Zhongguo Zhong Yao Za Zhi ; 41(13): 2532-2537, 2016 Jul.
Artigo em Zh | MEDLINE | ID: mdl-28905581

RESUMO

To compare the intestinal absorption and metabolism of icariin in different osteoporosis rat models. Ovariectomy and intragastric administration of cyclophosphamide were used to establish two kinds of rat osteoporosis models. Then the rat intestinal perfusion was conducted, and HPLC was used to measure and calculate the permeability coefficients of icariin in different intestines and production amount of metabolites. Western blot was used to detect LPH enzyme expression in two models. Experimental results showed that both ovariectomy and intragastric administration of cyclophosphamide 4.5 mg•kg⁻¹ could reduce rat bone density and successfully construct the rat osteoporosis models. The apparent permeability coefficient Papp of 20 µmol icariin in duodenum, jejunum, ileum, colon was 5.695, 5.224, 1.492, 0.520 respectively in sham operation group; 3.876, 3.608, 0.863, and 0.291 in ovariectomized group; 4.945, 3.601, 1.990, 1.042 in normal saline group; 3.301, 2.108, 1.209, 1.233 in cyclophosphamide-induced osteoporosis model group. In addition, the protein expression levels of LPH enzyme in two model groups were lower than those in normal group. The absorption and metabolism of icariin in two kinds of osteoporosis models was lower than that in sham operation group and normal saline group; the reduction of expression level of LPH enzymes in rat intestine of different osteoporosis models was one of the reasons for leading to the reduced intestinal absorption and metabolism of icariin.


Assuntos
Flavonoides/metabolismo , Absorção Intestinal , Osteoporose/metabolismo , Animais , Densidade Óssea , Feminino , Osteoporose/induzido quimicamente , Ovariectomia , Ratos , Ratos Sprague-Dawley
4.
Mol Pharm ; 11(10): 3307-21, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25058017

RESUMO

The study is aimed to develop a versatile reticular polyethylenimine (PEI) derivative eprosartan-g-PEI (ESP) conjugate-mediated targeted drug and gene codelivery system for tumor therapy. Eprosartan (ES), an angiotensin II type 1 receptor blocker (ARB), which has been proven to exert beneficial effects on tumor progression, vascularization, and metastasis as the conventional antihypertensive drug, was conjugated with PEI-1.8K chains into ESP via a bis-amide bond of pH-sensitivity to overcome high cytotoxicity and nontargeted gene delivery of PEI-25K. P53 gene was encapsulated in the ESP to form the codelivery system of ESP/p53 complexes, and this system was comprehensively characterized. In vitro ESP/p53 complexes had a significant effect on inhibiting angiogenesis by reducing the expression and secretion of VEGF. In vivo the effective antitumor activity of ESP/p53 complexes was observed on nude mice bearing PANC-1 xenografts, and the microvessel density (MVD) examination demonstrated that ESP/p53 complex-produced antitumor efficacy was closely correlated with the efficient angiogenesis repression. These findings disclosed that the multifunctional ESP/p53 complexes might be a promising dual anticancer drug and gene codelivery system.


Assuntos
Antineoplásicos/química , Sistemas de Liberação de Medicamentos/métodos , Polietilenoimina/química , Acrilatos/química , Acrilatos/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Humanos , Imidazóis/química , Imidazóis/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia de Força Atômica , Microvasos/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Tiofenos/química , Tiofenos/uso terapêutico
5.
ACS Appl Mater Interfaces ; 9(28): 23353-23369, 2017 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-28617574

RESUMO

Single-walled carbon nanotubes (SWNTs) with unique physicochemical properties have exhibited promising biomedical applications as drug and gene carriers. In this study, polyethylenimine (PEI)-modified SWNT conjugates linked with candesartan (CD) were developed to deliver vascular endothelial growth factor (VEGF)-targeted siRNA (siVEGF) for the synergistic and targeted treatment of tumor angiogenesis. The characterization results revealed that SWNT-PEI-CD conjugates were successfully synthesized and exhibited desirable dispersibility and superior stability. Confocal laser scanning microscopy (CLSM) and flow cytometry (FCM) results showed that SWNT-PEI-CD/siVEGF complexes could achieve high cellular uptake and specific intracellular distribution of siRNA in AT1R overexpressed PANC-1 cells. Strong down-regulation of VEGF was also verified by qualitative real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blot in complex-treated PANC-1 cells. The in vitro angiogenesis assay showed that SWNT-PEI-CD/siVEGF complexes highly inhibited tube formation of human umbilical vein endothelial cells. Furthermore, in vivo observation in PANC-1 xenografted nude mice demonstrated that SWNT-PEI-CD/siVEGF complexes exhibited significant distribution at tumor sites and caused obvious inhibition of tumor growth and tumor-associated angiogenesis repression induced by the drug combination of CD and siVEGF. Finally, a WST-1 assay indicated that SWNT-PEI-CD possessed low cytotoxicity, and a hemolysis test showed good biocompatibility of SWNT-PEI-CD. Hematological and histological analyses confirmed that SWNT-PEI-CD/siVEGF complexes did not cause any obvious toxic effects to blood and major organs. These findings suggested that the SWNT-PEI-CD/siVEGF co-delivery system with tumor-targeting specificity, improved endosomal escaping properties, and collaboration of angiogenesis inhibition could be a prospective method for efficient tumor antiangiogenic therapy.


Assuntos
Neovascularização Patológica , Animais , Benzimidazóis , Compostos de Bifenilo , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Nus , Nanotubos de Carbono , Neoplasias , Polietilenoimina , Estudos Prospectivos , RNA Interferente Pequeno , Tetrazóis , Fator A de Crescimento do Endotélio Vascular
6.
Biomaterials ; 139: 75-90, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28595131

RESUMO

Multi-walled carbon nanotube (MWNT) with its versatility has exhibited tremendous superiority in drug delivery. Despite plenty of researches on MWNT based delivery systems, precision-guided assistances to maximize their profitable properties are still lacking in substantive progress. We developed here a dual-targeting and co-delivery system based on MWNT for antiangiogenesis therapy in lung cancer which aimed at renin-angiotensin system (RAS) dysregulation by synergistically conducting angiotensin II type 1 receptor (AT1R) and type 2 receptor (AT2R) pathway. In this work, iRGD peptide connected to polyethyleneimine (PEI) was linked to MWNT skeleton, accompanying with candesartan (CD) conjugated to MWNT mediated by cystamine (SS). The functionalized MWNT is assembled with plasmid AT2 (pAT2) to form iRGD-PEI-MWNT-SS-CD/pAT2 complexes. iRGD and CD act as pilots for complexes to dually target symbolic ανß3-integrin and AT1R both overexpressed on tumor angiogenic endothelium and lung cancer cell. CD as chemotherapy showed synergistic downregulation of VEGF when combining of pAT2 and efficiently inhibited angiogenesis. iRGD-PEI-MWNT-SS-CD/pAT2 complexes greatly appreciated drug activities by changing drug distribution and exhibited remarkable tumor growth suppression in A549 xenograft nude mice. Our work presents that such dual-targeting strategy highly improves the delivery performance of MWNT and open a new avenue for RAS related lung cancer therapy.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Antineoplásicos/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Nanotubos de Carbono/química , Sistema Renina-Angiotensina/efeitos dos fármacos , Células A549 , Inibidores da Angiogênese/síntese química , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Animais , Antineoplásicos/síntese química , Benzimidazóis/química , Compostos de Bifenilo , Cistamina/química , Sistemas de Liberação de Medicamentos , Sinergismo Farmacológico , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Pulmonares/irrigação sanguínea , Camundongos , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Oligopeptídeos/química , Plasmídeos/química , Polietilenoimina/química , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 2 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/metabolismo , Tetrazóis/química , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
ACS Biomater Sci Eng ; 3(12): 3261-3272, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33445369

RESUMO

In postgraphene two-dimensional materials (2DMs), MoS2 has attracted increasing attention in the biomedical field due to its excellent physicochemical properties. However, the toxicity and biocompatibility evaluation of MoS2 is not fully addressed. Herein, chitosan functionalized MoS2 (CS-MoS2) nanosheets, which showed perfect dispersibility and stability performances, were synthesized and characterized. We found that CS-MoS2 nanosheets inhibited the viability of human dermal fibroblasts (HDFs) moderately while causing cell membrane instability, ROS generation, and DNA damage in a dosage-dependent manner. CS-MoS2 nanosheets did not induce significant changes in the cell morphologies, but they seemed to impair the cell division of HDFs. CS-MoS2 nanosheets (100 µg/mL) activated EGFR and induced reactive oxygen species, Smad, and IL-1, which in turn led to cell inflammation and apoptosis. Furthermore, HDFs showed cellular stress responses when they were exposed to low concentrations of CS-MoS2 nanosheets (25 and 100 µg/mL) because most of the intracellular metabolites such as amino acids were induced at 25 µg/mL but were inhibited at 100 µg/mL. Pyroglutamic acid, phosphoric acid, and inositol might be used as biomarkers for evaluating the toxicity of CS-MoS2 nanosheets. Additionally, 100 µg/mL CS-MoS2 nanosheets inhibited glutathione metabolism and induced the imbalance of cellular redox homeostasis. It further suppressed the tricarboxylic acid cycle and other metabolic pathways, causing insufficient supply of substrates and energy for HDFs. These findings will fuel the risk assessment of MoS2 and other 2DMs and guide the safe material design and 2DM applications.

8.
Mater Sci Eng C Mater Biol Appl ; 56: 280-5, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26249591

RESUMO

A new cationic polymer eprosartan-graft-PEI (ESP) containing eprosartan (ES) and polyethylenimine 1.8K was successfully developed and employed as a safe gene vector to assemble a drug (ES) and gene co-delivery complex (ESP/pDNA). Chondroitin sulfate (CS) was then used as a coating polymer to shield the surface charge of ESP/pDNA complexes, as well as a tumor targeting entity to ensure specific delivery of CS/ESP/pDNA complexes. The CS/ESP/pDNA complexes with desirable particle size and zeta potential, exhibited amidase-responsive drug release and CS-mediated endocytosis in vitro. As compared with ESP/pDNA complexes, in vivo imaging results demonstrated decreased reticuloendothelial system uptake and remarkably increased tumor accumulation of CS/ESP/pDNA complexes. All these findings indicated the potential of CS/ESP/pDNA as a promising tumor-targeted drug and gene co-delivery system.


Assuntos
Acrilatos , Sulfatos de Condroitina , Sistemas de Liberação de Medicamentos/métodos , Técnicas de Transferência de Genes , Imidazóis , Plasmídeos , Polietilenoimina , Tiofenos , Acrilatos/química , Acrilatos/farmacocinética , Acrilatos/farmacologia , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacocinética , Sulfatos de Condroitina/farmacologia , Endocitose , Células Hep G2 , Humanos , Imidazóis/química , Imidazóis/farmacocinética , Imidazóis/farmacologia , Neoplasias , Plasmídeos/química , Plasmídeos/farmacocinética , Plasmídeos/farmacologia , Polietilenoimina/química , Polietilenoimina/farmacocinética , Polietilenoimina/farmacologia , Tiofenos/química , Tiofenos/farmacocinética , Tiofenos/farmacologia
9.
Biomaterials ; 33(34): 8893-905, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22979990

RESUMO

RNA interference holds tremendous potential as a therapeutic approach of malignant tumors. However, safe and efficient nanovectors are extremely lack for systemic delivery of small interfering RNA (siRNA). The study aimed to develop a biomimetic nanovector, reconstituted high density lipoprotein (rHDL), mediating targeted cholesterol-conjugated siRNA (Chol-siRNA) delivery for Pokemon gene silencing therapy. Chol-siRNA-loaded rHDL nanoparticles (rHDL/Chol-siRNA complexes) were prepared using thin-film dispersion method and their characteristics were investigated in detail. RHDL/Chol-siRNA complexes at the optimal volume ratio (lipid: Chol-siRNA) exhibited high Chol-siRNA-loading efficiency (~99%), desirable nanoparticle size and excellent stability in serum. In addition, by analyzing Chol-siRNA release profile, rHDL/Chol-siRNA complexes displayed sustained-release characteristic and storage stability. Observations from FACS and confocal microscopic analyses revealed that rHDL-mediated carboxyfluorescein tagged Chol-siRNA (FAM-Chol-siRNA) transfection resulted in highly efficient uptake and specific cytoplasmic delivery of FAM-Chol-siRNA into human hepatocellular carcinoma cell line HepG2 via HDL-receptor mediated mechanism. In vitro cytotoxicity, apoptosis and Western-blot analyses revealed significant cellular growth inhibition and decrease of Pokemon and Bcl-2 protein expression in HepG2 cells treated with Chol-siRNA-Pokemon-loaded rHDL nanoparticles (rHDL/Chol-siRNA-Pokemon complexes), respectively. In in vivo studies, the near-infrared (NIR) dye Cy5 labeled Chol-siRNA-loaded rHDL nanoparticles (rHDL/Cy5-Chol-siRNA complexes) obviously accumulated in tumor of nude mice after i.v. administration as compared with Cy5-Chol-siRNA-loaded lipoplexes (Lipos/Cy5-Chol-siRNA complexes). Morover, rHDL/Chol-siRNA-Pokemon complexes demonstrated great tumor growth inhibition and significant decrease of Pokemon and Bcl-2 protein expression in vivo. These results suggested that rHDL should be an ideal non-viral tumor-targeting vector for Chol-siRNA transfer, and rHDL-mediated Chol-siRNA-Pokemon delivery might be a promising new strategy for gene therapy in hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/terapia , Colesterol/química , Proteínas de Ligação a DNA/genética , Neoplasias Hepáticas/terapia , Nanopartículas/química , Interferência de RNA , RNA Interferente Pequeno/uso terapêutico , Fatores de Transcrição/genética , Animais , Carcinoma Hepatocelular/genética , HDL-Colesterol/química , Terapia Genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética
10.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 42(2): 80-4, 2007 Feb.
Artigo em Zh | MEDLINE | ID: mdl-17462151

RESUMO

OBJECTIVE: To investigate the imtrusion of overerupted molars with microscrews as anchorage. METHODS: Thirteen adult patients were treated with microscrew anchorage and fixed appliances. Twenty-three overerupted posterior maxillary teeth were intruded. The intrusive movement was investigated on cephalometric radiographs. RESULTS: The molars were intruded and the occlusal plane was corrected successfully in all patients. The treatment period of intrusion was from 5 to 18 months (mean 10.4 months). Significant true intrusion of overerupted maxillary molars, ranged from 0.45 mm to 7.00 mm [mean (2.86 +/- 1.80) mm], was achieved (P < 0.001). The apical root resorption was not clinically significant and the bone level was unchanged. CONCLUSIONS: The microscrew anchorage and fixed appliances were applicable and efficacious for intrusion of overerupted maxillary molars.


Assuntos
Parafusos Ósseos , Dente Molar/anormalidades , Procedimentos de Ancoragem Ortodôntica/instrumentação , Técnicas de Movimentação Dentária/instrumentação , Adulto , Cefalometria , Implantação Dentária , Feminino , Humanos , Masculino , Maxila/cirurgia , Pessoa de Meia-Idade , Dente Molar/cirurgia , Procedimentos de Ancoragem Ortodôntica/métodos , Técnicas de Movimentação Dentária/métodos , Resultado do Tratamento , Adulto Jovem
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