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1.
J Laryngol Otol ; 138(3): 297-300, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37646292

RESUMEN

OBJECTIVE: This study aimed to use short-form visual analogue scale cochlear implantation questionnaires to evaluate subjective aspects at each out-patient visit. The correlation between subjective hearing tests using the short-form visual analogue scale and objective hearing outcomes was evaluated. METHOD: This study was conducted in a single centre. Cochlear implant users (n = 199) evaluated their hearing on a scale of 0 to 100 for the right, left and both ears. The Japanese speech perception test (CI-2004) Japanese monosyllable speech perception test (67-S) and cochlear implantation threshold were used for the objective cochlear implantation evaluation. RESULTS: A significant correlation was found between the short-form visual analogue scale questionnaire and objective hearing outcome, for words (r = 0.64) and sentences (r = 0.62) in CI-2004 and 67-S (r = 0.56) tests. No significant correlation was found between the short-form visual analogue scale score and cochlear implantation threshold (r = -0.18). CONCLUSION: Short-form visual analogue scale cochlear implantation questionnaires mean cochlear implant users spend less time answering subjective visual analogue scale questionnaires, and clinicians estimate a patient's cochlear implantation hearing and abnormality by chronological evaluation.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Percepción del Habla , Humanos , Escala Visual Analógica , Audición
2.
Radiat Res ; 192(3): 241-250, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30430917

RESUMEN

The purpose of the current study was to characterize the effects of simulated microgravity and radiation-induced changes in retina and retinal vasculature, and to assess the accompanying early changes in immune cells and hematological parameters. To better understand the effects of spaceflight, we used a combination of treatments designed to simulate both the radiation and low-gravity aspects of space conditions. To simulate the broad energy spectrum of a large solar particle event (SPE) and galactic cosmic ray (GCR) radiation, male C57BL/6J mice were exposed to whole-body irradiation using fully modulated beams of 150-MeV protons containing particles of energy from 0 to 150 MeV and a uniform dose-vs.-depth profile. The mice were also hindlimb-unloaded (HLU) by tail suspension. Mice were unloaded for 7 days, exposed to 50 cGy, unloaded for an additional 7 days and then sacrificed for tissue isolation at days 4 and 30 after the combined treatments. Increases in the number of apoptotic cells were observed in the endothelial cells of mice that received radiation alone or with HLU compared to controls at both days 4 and 30 (P < 0.05). Endothelial nitric oxide synthase (eNOS) levels were significantly elevated in the retina after irradiation only or combined with HLU compared to controls at the 30-day time point (P < 0.05). The most robust changes were observed in the combination group, suggesting a synergistic response to radiation and unloading. For hematopoietic parameters, our analysis indicated the main effects for time and radiation at day 4 after treatments (day 11 postirradiation) (P < 0.05), but a smaller influence of HLU for both white blood cell and lymphocyte counts. The group treated with both radiation and HLU showed greater than 50% reduction in lymphocyte counts compared to controls. Radiation-dependent differences were also noted in specific lymphocyte subpopulations (T, B, natural killer cells). This study shows indications of an early effect of low-dose radiation and spaceflight conditions on retina and immune populations.


Asunto(s)
Sistema Hematopoyético/efectos de la radiación , Protones/efectos adversos , Retina/efectos de la radiación , Simulación de Ingravidez/efectos adversos , Animales , Peso Corporal/efectos de la radiación , Recuento de Células , Relación Dosis-Respuesta en la Radiación , Células Endoteliales/efectos de la radiación , Medio Ambiente Extraterrestre , Linfocitos/citología , Linfocitos/efectos de la radiación , Masculino , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico Sintasa de Tipo III/metabolismo , Retina/citología , Bazo/efectos de la radiación , Factores de Tiempo
3.
Nat Commun ; 8(1): 1001, 2017 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-29042554

RESUMEN

Recently, nanocarriers that transport bioactive substances to a target site in the body have attracted considerable attention and undergone rapid progression in terms of the state of the art. However, few nanocarriers can enter the brain via a systemic route through the blood-brain barrier (BBB) to efficiently reach neurons. Here we prepare a self-assembled supramolecular nanocarrier with a surface featuring properly configured glucose. The BBB crossing and brain accumulation of this nanocarrier are boosted by the rapid glycaemic increase after fasting and by the putative phenomenon of the highly expressed glucose transporter-1 (GLUT1) in brain capillary endothelial cells migrating from the luminal to the abluminal plasma membrane. The precisely controlled glucose density on the surface of the nanocarrier enables the regulation of its distribution within the brain, and thus is successfully optimized to increase the number of nanocarriers accumulating in neurons.There are only a few examples of nanocarriers that can transport bioactive substances across the blood-brain barrier. Here the authors show that by rapid glycaemic increase the accumulation of a glucosylated nanocarrier in the brain can be controlled.


Asunto(s)
Glucemia/metabolismo , Barrera Hematoencefálica/metabolismo , Encéfalo/metabolismo , Portadores de Fármacos/farmacocinética , Animales , Encéfalo/irrigación sanguínea , Portadores de Fármacos/metabolismo , Femenino , Glucosa/metabolismo , Transportador de Glucosa de Tipo 1/metabolismo , Glicosilación , Humanos , Ratones Endogámicos BALB C , Micelas , Microscopía Confocal , Nanopartículas/metabolismo , Neuronas/metabolismo , Polímeros/química , Polímeros/metabolismo
4.
J Control Release ; 258: 56-66, 2017 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-28483513

RESUMEN

Current therapeutic strategies against glioblastoma multiforme (GBM) are futile mainly because of the poor access of drugs into malignant tissues, which is hindered by the tight blood-brain tumor barrier in the GBM vasculature. Nanomedicines have shown potential for circumventing the vascular barriers of GBM, particularly by targeting markers on the luminal side of endothelial cells in the blood vessels of GBM for achieving effective and selective translocation into the tumor. Thus, as the αvß3 and αvß5 integrins overexpressed on the endothelial cells of GBM can be targeted by cyclic-Arg-Gly-Asp (cRGD) peptide, herein, we developed cRGD-installed micellar nanomedicines loading epirubicin, the potent antiglioblastoma agent, through a pH-sensitive hydrazone-bond for effective treatment of GBM. These cRGD-installed epirubicin-loaded polymeric micelles (cRGD-Epi/m) achieved faster and higher penetration into U87MG cell-derived 3D-spheroids than the micelles without cRGD, conceivably through a cRGD-integrin mediated pathway. In vivo, the cRGD-installed micelles effectively suppressed the growth of an orthotopic GBM model by delivering high levels of epirubicin throughout the tumor tissue. These results indicate significant prospects for cRGD-Epi/m as an effective and translationable treatment against GBM.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/tratamiento farmacológico , Portadores de Fármacos/química , Epirrubicina/administración & dosificación , Glioblastoma/tratamiento farmacológico , Micelas , Péptidos Cíclicos/química , Animales , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/uso terapéutico , Encéfalo/efectos de los fármacos , Encéfalo/patología , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Sistemas de Liberación de Medicamentos , Epirrubicina/farmacocinética , Epirrubicina/uso terapéutico , Femenino , Glioblastoma/patología , Humanos , Ratones Endogámicos BALB C , Polietilenglicoles/química
5.
Rev Sci Instrum ; 87(2): 024501, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26931871

RESUMEN

We have generated over 40 GPa pressures, namely, 43 and 44 GPa, at ambient temperature and 2000 K, respectively, using Kawai-type multi-anvil presses (KMAP) with tungsten carbide anvils for the first time. These high-pressure generations were achieved by combining the following pressure-generation techniques: (1) precisely aligned guide block systems, (2) high hardness of tungsten carbide, (3) tapering of second-stage anvil faces, (4) materials with high bulk modulus in a high-pressure cell, and (5) high heating efficiency.

6.
J Control Release ; 188: 67-77, 2014 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-24892974

RESUMEN

The ubiquitin-proteasome system is central in the regulation of cellular proteins controlling cell cycle progression and apoptosis, drawing much interest for developing effective targeted cancer therapies. Herein, we developed a novel pH-responsive polymeric-micelle-based carrier system to effectively deliver the proteasome inhibitor MG132 into cancer cells. MG132 is covalently bound to the block copolymer composed of polyethylene glycol (PEG) and polyaspartate through an acid-labile hydrazone bond. This bond is stable at physiological condition, but hydrolytically degradable in acidic compartments in the cell, such as late-endosomes and lysosomes, and thus, it was used for controlled release of MG132 after EPR-mediated preferential accumulation of the micelles into the tumor. MG132-loaded micelles have monodispersed size distribution with an average diameter of 45nm, and critical micelle concentration is well below 10(-7)M. In vitro studies against several cancer cell lines confirmed that MG132-loaded micelles retained the cytotoxic effect, and this activity was indeed due to the inhibition of proteasome by released MG132 from the micelles. Real-time in vitro confocal-microscopy experiments clearly indicated that MG132-conjugated micelles disintegrated only inside the target cells. By intravital confocal micro-videography, we also confirmed the prolonged circulation of MG132 loaded micelles in the bloodstream, which lead to tumor specific accumulation of micelles, as confirmed by in vivo imaging 24h after injection. These micelles showed significantly lower in vivo toxicity than free MG132, while achieving remarkable antitumor effect against a subcutaneous HeLa-luc tumor model. Our findings create a paradigm for future development of polymeric-micelle-based carrier system for other peptide aldehyde type proteasome inhibitors to make them effective cohort of the existing cancer therapeutic regiments.


Asunto(s)
Antineoplásicos/administración & dosificación , Preparaciones de Acción Retardada/química , Leupeptinas/administración & dosificación , Micelas , Inhibidores de Proteasoma/administración & dosificación , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Femenino , Humanos , Concentración de Iones de Hidrógeno , Leupeptinas/farmacocinética , Leupeptinas/uso terapéutico , Ratones Endogámicos BALB C , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Polímeros/química , Inhibidores de Proteasoma/farmacocinética , Inhibidores de Proteasoma/uso terapéutico
11.
J Mater Chem B ; 2(26): 4130-4133, 2014 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-32261745

RESUMEN

Magnetically-transportable core-shell emulsion droplets with an antioxidative all-organic paramagnetic liquid shell [Nitroxide Radical Liquid (NRL) microcapsules] were demonstrated. We successfully fabricated stable NRL microcapsules with microfluidic devices. The NRL microcapsules are magnetically transportable and are likely to protect the inner phase from oxidants. Consequently, the NRL microcapsules can serve as a flexible antioxidative magnetic carrier for nanoliter cargoes.

12.
Endoscopy ; 45(8): 649-54, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23881805

RESUMEN

BACKGROUND AND STUDY AIM: A reliable full-thickness suturing device is necessary for pure natural orifice transluminal endoscopic surgery (NOTES). The present study focused on assessing the reliability of a new suturing device. METHODS: A total of 60 single sutures were tested to close 5-cm incisions in 8-cm square pieces of resected swine stomach. Each incision was sutured by an over-the-scope clip (OTSC; n = 20), a single hand-sewn stitch (n = 20), or a single triple-arm-bar suturing system (TBSS) stitch. The maximum pulling force durability (MPD) of each suture was tested. To assess the reliability of the TBSS for endoscopic full-thickness resection (EFTR), 60 EFTRs of 50 mm diameter were performed on excised swine stomachs. After EFTR, full-thickness sutures were made using 3-stitch OTSCs (n = 20), 10-stitch hand-sewn sutures (n = 20), or 10-stitch TBSS sutures (n = 20). Outcomes were the MPD test for both single stitch and multiple stitch applications and the suturing time for single-stitch sutures. RESULTS: In the single-stitch MPD tests, there were significant differences between OTSCs and hand-sewn sutures (P = 0.0002) and between OTSCs and TBSS sutures (P = 0.0001), but no significant difference between hand-sewn and TBSS sutures. The multiple-stitch sutures revealed significant differences between OTSCs and hand-sewn sutures (P = 0.0039), and between OTSCs and TBSS sutures (P = 0.013). There was no significant difference between hand-sewn and TBSS sutures. There were significant differences in suture times between OTSC, hand-sewn sutures, and TBSS sutures (P < 0.05). CONCLUSIONS: Both single-stitch and multiple-stitch sutures using TBSS have similar strength to hand-sewn sutures. TBSS is a reliable suturing device.


Asunto(s)
Cirugía Endoscópica por Orificios Naturales/instrumentación , Estómago/cirugía , Técnicas de Sutura/instrumentación , Animales , Porcinos , Resistencia a la Tracción
14.
J Dent Res ; 91(11): 1043-8, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22914536

RESUMEN

To determine the amount of 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-calcium (MDP-Ca) salt produced through the demineralization of enamel or dentin by MDP, we designed experimental MDP-based one-step adhesives with different amounts of MDP. The null hypotheses were that (1) the amount of MDP-Ca salt produced through the demineralization of enamel was the same as that for dentin, and (2) the amounts of MDP-Ca salt have no effect on bonding performance. Increases in the amount of MDP resulted in increased amounts of MDP-Ca salt. The production amount of MDP-Ca salt of the dentin was 1.3 times higher than that of the enamel. The predominant species of the MDP and enamel reactants was a calcium hydrogen phosphate of MDP. In contrast, the dentin yielded both calcium phosphate and calcium hydrogen phosphate of MDP. Increases in the amount of MDP-Ca salt decreased both enamel and dentin bond strengths. An optimal concentration of MDP exists in one-step self-etch adhesives.


Asunto(s)
Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios/química , Metacrilatos/química , Cementos de Resina/química , Grabado Ácido Dental/métodos , Animales , Fosfatos de Calcio/análisis , Bovinos , Esmalte Dental/química , Análisis del Estrés Dental , Dentina/química , Recubrimientos Dentinarios/síntesis química , Espectroscopía de Resonancia Magnética/métodos , Cementos de Resina/síntesis química , Resistencia al Corte , Propiedades de Superficie , Desmineralización Dental
15.
Endoscopy ; 44(7): 641-8, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22696191

RESUMEN

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) of large gastric lesions results in an extensive artificial ulcer that can lead to marked gastric deformity. The aim of the current study was to evaluate therapeutic efficacy in the prevention of gastric deformity of local triamcinolone acetonide (TCA) injection into the extensive artificial ulcer following ESD. PATIENTS AND METHODS: A total of 45 patients who were diagnosed with early gastric cancer were enrolled. Patients were randomly assigned by the sealed-envelope randomization method to either local TCA injections (n = 21) or sham-control (n = 20) groups. Two clips were placed at the two maximum outer edges of the artificial ulcer after the lesion had been resected (Day 0). Local TCA injections were performed on postoperative Day 5 and Day 12. The distance between the two clips was measured by endoscopic measuring forceps on Days 5, 12, 30, and 60. Granulation formation and gastric deformity were evaluated by visual analog scale (VAS) on Days 30 and 60. RESULTS: Local TCA injection did not alter clip-to-clip distance on postoperative Day 60, and formation of flat granulation tissue over the ulcer was followed by regenerative mucosa without any gastric deformity. The sham-control group showed significant shortening of clip-to-clip distance compared with the local steroid-injected group and protruded forms of granulation tissue with mucosal convergence. Histological evaluation revealed prominent growth of neovessels, swelling, and marked increases in endothelial cells in the local steroid-injected group compared with the sham-control group. CONCLUSIONS: Local steroid injection into the floor of a post-ESD artificial ulcer promotes the formation of granulation tissue at an early stage of the healing process leading to regeneration of gastric mucosa without mucosal convergence or gastric deformity.


Asunto(s)
Adenocarcinoma , Gastroscopía , Tejido de Granulación/efectos de los fármacos , Neoplasias Gástricas , Úlcera Gástrica , Triamcinolona Acetonida/administración & dosificación , Adenocarcinoma/patología , Adenocarcinoma/fisiopatología , Adenocarcinoma/cirugía , Anciano , Anciano de 80 o más Años , Disección/efectos adversos , Disección/métodos , Intervención Médica Temprana , Femenino , Mucosa Gástrica/patología , Mucosa Gástrica/cirugía , Gastroscopía/efectos adversos , Gastroscopía/métodos , Glucocorticoides/administración & dosificación , Humanos , Inyecciones Intralesiones/métodos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Gástricas/patología , Neoplasias Gástricas/fisiopatología , Neoplasias Gástricas/cirugía , Úlcera Gástrica/etiología , Úlcera Gástrica/fisiopatología , Úlcera Gástrica/terapia , Resultado del Tratamiento , Cicatrización de Heridas/efectos de los fármacos
17.
J Control Release ; 159(2): 189-96, 2012 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-22326402

RESUMEN

Nano-scaled drug carriers have great potential for the treatment of solid tumors. Nevertheless, hypovascularity and fibrosis in some types of solid tumors have been demonstrated to reduce the penetration and accumulation of nano-scaled drug carriers. Diffuse-type scirrhous gastric cancers present such characteristics as well as frequent metastasis to the lymph nodes; therefore, it remains a great challenge to eradicate scirrhous gastric cancers based on the drug targeting using nanocarriers. Herein, we demonstrated that polymeric micelles with 30-nm diameter incorporating (1,2-diaminocyclohexane)platinum(II) (DACHPt), the parent complex of the anticancer drug oxaliplatin, efficiently penetrated and accumulated in an orthotopic scirrhous gastric cancer model, leading to the inhibition of the tumor growth. Moreover, the elevated localization of systemically injected DACHPt-loaded micelles in metastastic lymph nodes reduced the metastatic tumor growth. These results suggest DACHPt-loaded micelles as a promising nanocarrier for the treatment of scirrhous gastric cancers and their lymphatic metastases.


Asunto(s)
Adenocarcinoma Escirroso/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Portadores de Fármacos/química , Compuestos Organoplatinos/uso terapéutico , Polietilenglicoles/química , Ácido Poliglutámico/química , Polímeros/química , Neoplasias Gástricas/tratamiento farmacológico , Adenocarcinoma Escirroso/patología , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacocinética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Humanos , Metástasis Linfática , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Micelas , Compuestos Organoplatinos/administración & dosificación , Compuestos Organoplatinos/farmacocinética , Neoplasias Gástricas/patología , Distribución Tisular , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Herz ; 37(2): 217-8, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21748385

RESUMEN

A 58-year-old male was referred for catheter ablation for atrial fibrillation. He was incidentally diagnosed with cor triatriatum sinister by preoperative transesophageal echocardiography and cardiovascular computed tomography. The patient has since been free from atrial fibrillation for over 24 months following successful electrical pulmonary vein isolation. The rapidly soaring number of cases undergoing catheter ablation for atrial fibrillation and imaging investigation prior to the procedure may increase the incidental detection of asymptomatic congenital heart diseases.


Asunto(s)
Fibrilación Atrial/cirugía , Corazón Triatrial/diagnóstico , Corazón Triatrial/cirugía , Fibrilación Atrial/complicaciones , Corazón Triatrial/complicaciones , Humanos , Hallazgos Incidentales , Masculino , Persona de Mediana Edad
19.
Nat Nanotechnol ; 6(12): 815-23, 2011 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-22020122

RESUMEN

A major goal in cancer research is to develop carriers that can deliver drugs effectively and without side effects. Liposomal and particulate carriers with diameters of ∼100 nm have been widely used to improve the distribution and tumour accumulation of cancer drugs, but so far they have only been effective for treating highly permeable tumours. Here, we compare the accumulation and effectiveness of different sizes of long-circulating, drug-loaded polymeric micelles (with diameters of 30, 50, 70 and 100 nm) in both highly and poorly permeable tumours. All the polymer micelles penetrated highly permeable tumours in mice, but only the 30 nm micelles could penetrate poorly permeable pancreatic tumours to achieve an antitumour effect. We also showed that the penetration and efficacy of the larger micelles could be enhanced by using a transforming growth factor-ß inhibitor to increase the permeability of the tumours.


Asunto(s)
Portadores de Fármacos/farmacocinética , Micelas , Neoplasias Pancreáticas/metabolismo , Animales , Antineoplásicos/administración & dosificación , Humanos , Liposomas/farmacocinética , Ratones , Ratones Endogámicos BALB C , Compuestos Organoplatinos/administración & dosificación , Tamaño de la Partícula , Permeabilidad/efectos de los fármacos , Polietilenglicoles/química , Pirazoles/administración & dosificación , Pirroles/administración & dosificación , Factor de Crecimiento Transformador beta/antagonistas & inhibidores
20.
J Control Release ; 156(3): 364-73, 2011 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-21843561

RESUMEN

α(v)ß(3) and α(v)ß(5) integrins are attractive target structures for cancer therapy as they are upregulated in tumor and tumor associated host cells and play a pivotal role for tumor growth and metastasis. Gene vectors such as polyplex micelles consisting of thiolated PEG-block-poly(lysine) copolymers complexed with plasmid DNA can be targeted to these specific integrins by equipment with a cyclic RGD peptide. In this study, we analyzed the effect of the RGD ligand on micelle endocytosis by comparing fluorescently labeled, targeted and untargeted micelles in live-cell imaging experiments with highly sensitive fluorescence microscopy and flow cytometry. Two micelle types with 12 kDa (PEG12) and 17 kDa (PEG17) PEG shell layers were examined to evaluate the influence of surface shielding on the internalization characteristics. Our results reveal three major effects: First, the RGD ligand accelerates the internalization of micelles into integrin expressing HeLa cells without changing the uptake pathway of the micelles. Both targeted as well as untargeted micelles are predominantly internalized via clathrin mediated endocytosis. Second, the PEG shielding of micelles has an important effect on their targeting specificity. At high PEG shielding selective endocytosis of integrin targeted micelles occurs, whereas at low PEG shielding targeted and untargeted micelles show comparable internalization. In addition, PEG17 RGD(+) micelles induce the highest reporter gene expression. Third, our data demonstrate a clear influence of the applied micelle dose on the internalization of integrin targeted micelles. We propose that PEG17 shielded micelles equipped with a cyclic RGD ligand are the favored system of choice for clinical therapy as they exhibit higher transgene expression, a higher specificity for integrin-dependent endocytosis compared to PEG12 shielded micelles, and are functional at low doses as well.


Asunto(s)
Sistemas de Liberación de Medicamentos , Endocitosis , Micelas , Oligopéptidos/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Genes Reporteros , Células HeLa , Humanos , Integrinas/metabolismo , Luciferasas/genética , Microscopía Confocal , Microscopía Fluorescente , Oligopéptidos/análisis , Polietilenglicoles/química
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