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1.
Phys Chem Chem Phys ; 18(39): 27102-27108, 2016 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-27402555

RESUMEN

The CH3NH3PbI3 perovskite solar cells have been fabricated using three-porous-layered electrodes as, 〈glass/F-doped tin oxide (FTO)/dense TiO2/porous TiO2-perovskite/porous ZrO2-perovskite/porous carbon-perovskite〉 for light stability tests. Without encapsulation in air, the CH3NH3PbI3 perovskite solar cells maintained 80% of photoenergy conversion efficiency from the initial value up to 100 h under light irradiation (AM 1.5, 100 mW cm-2). Considering the color variation of the CH3NH3PbI3 perovskite layer, the significant improvement of light stability is due to the moisture-blocking effect of the porous carbon back electrodes. The strong interaction between carbon and CH3NH3PbI3 perovskite was proposed by the measurements of X-ray photoelectron spectroscopy and X-ray diffraction of the porous carbon-perovskite layers.

2.
Nanomedicine ; 11(1): 229-38, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25229542

RESUMEN

Multi-modal thermo-sensitive polymer-modified liposomes (MTPLs) containing an anticancer drug, MR contrast agent, and fluorescent dye have been investigated as "theranostic" nanodevices that can be used to monitor drug delivery in cancer therapy. Here, we measured the physical characteristics of MTPLs, observed the dynamics of MTPLs in vivo, visualized heat-triggered drug release using MRI, and evaluated the treatment effects of the MTPLs with and without heating. In vitro experiments demonstrated that the MTPLs released drugs at temperatures above 41°C. In vivo MTPLs accumulated in tumor tissue, with the accumulation maximized for 4-12hours. MR signal in the tumor was significantly elevated after mild heating for 15 minutes, indicating release of the contrast agent from the MTPLs was facilitated by heat-triggering. Tumor size after treatment with MTPLs and heating was significantly smaller than those of the control groups. In conclusion, MTPLs with MRI are useful for low-invasive cancer theranostics.


Asunto(s)
Antineoplásicos/química , Sistemas de Liberación de Medicamentos , Liposomas/química , Neoplasias/patología , Polímeros/química , Animales , Línea Celular Tumoral , Medios de Contraste/química , Doxorrubicina/administración & dosificación , Femenino , Colorantes Fluorescentes/química , Calor , Imagen por Resonancia Magnética , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Nanomedicina , Nanopartículas/química , Trasplante de Neoplasias , Neoplasias/metabolismo
3.
Sci Rep ; 14(1): 14358, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38906976

RESUMEN

A intermediate multidomain state and large crystallographic tilting of 1.78° for the (hh0)pc planes of a (001)pc-oriented single-domain Mn-doped BiFeO3 (BFMO) thin film were found when an electric field was applied along the [110]pc direction. The anomalous crystallographic tilting was caused by ferroelastic domain switching of the 109° domain switching. In addition, ferroelastic domain switching occurred via an intermediate multidomain state. To investigate these switching dynamics under an electric field, we used in situ fluorescent X-ray induced Kossel line pattern measurements with synchrotron radiation. In addition, in situ inverse X-ray fluorescence holography (XFH) experiments revealed that atomic displacement occurred under an applied electric field. We attributed the atomic displacement to crystallographic tilting induced by a converse piezoelectric effect. Our findings provide important insights for the design of piezoelectric and ferroelectric materials and devices.

4.
Sci Rep ; 14(1): 5858, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467855

RESUMEN

The relationship between oral functions and dementia was examined in 7384 older adults (age ≥ 75 years) who visited a dental clinic in Gifu, Japan. Participants without dementia in a baseline survey in April 2018 were followed until March 2021. As oral functions, chewing function, tongue and lip function, and swallowing function were assessed by self-administered questionnaire, by oral diadochokinesis test, and by repetitive saliva swallowing test, respectively. The presence of systemic diseases was based on data obtained from the National Database of Health Insurance of Japan. At follow-up, 415 (6%) participants were diagnosed with dementia. Multivariate logistic regression analyses showed the presence of dementia at follow-up was associated with female (odds ratio [OR] 1.386; 95% confidence interval [CI] 1.117-1.719), age (OR 1.078; CI 1.056-1.101), regular dental checkups (absence; OR 1.452; CI 1.180-1.788), brushing frequency ≥ twice/day (absence; OR 1.510; CI 1.194-1.911), decayed teeth (presence; OR 1.328; CI 1.071-1.648), swallowing function (poor; OR 1.484; CI 1.135-1.939) at baseline. It was found that poor swallowing function was associated with the future onset of dementia.


Asunto(s)
Trastornos de Deglución , Demencia , Humanos , Femenino , Anciano , Japón/epidemiología , Deglución , Cepillado Dental , Demencia/epidemiología , Salud Bucal
5.
Artículo en Inglés | MEDLINE | ID: mdl-38928921

RESUMEN

Predictive factors associated with a decline in swallowing function after 2 years were examined in 3409 Japanese older people aged ≥ 75 years who had undergone a dental checkup in Gifu Prefecture, Japan. Participants with normal swallowing function in a baseline survey in April 2018 were followed for 2 years. Swallowing function was assessed using a repetitive saliva swallowing test. In our study, 429 participants (13%) who were swallowing less than three times in 30 s based on a repetitive saliva swallowing test after 2 years were diagnosed as those with decline in swallowing function. Multivariate logistic regression analyses showed the decline in swallowing function after 2 years was associated with the male gender (odds ratio [ORs]: 0.772; 95% confidence interval [CIs]: 0.615-0.969), age ≥ 81 years (presence; ORs: 1.523; 95% CIs: 1.224-1.895), support/care-need certification (presence; ORs: 1.815; 95% CIs: 1.361-2.394), periodontal pocket depth (PPD) ≥ 4 mm (presence; ORs: 1.469; 95% CIs: 1.163-1.856), difficulty in biting hard food (yes; ORs: 1.439; 95% CIs: 1.145-1.808), choking on tea and water (yes; ORs: 2.543; 95% CIs: 2.025-3.193), and dry mouth (yes; ORs: 1.316; 95% CIs: 1.052-1.646) at baseline. Therefore, the dental checkup items associated with a decline in swallowing function after 2 years were a PPD ≥ 4 mm, difficulty in biting hard food, choking on tea and water, and dry mouth. PPD status and confirming to the self-administered questionnaire about biting, choking, and dry mouth may be useful in predicting future decline in swallowing function.


Asunto(s)
Deglución , Humanos , Anciano , Masculino , Femenino , Japón , Anciano de 80 o más Años , Deglución/fisiología , Trastornos de Deglución , Factores de Riesgo , Pueblos del Este de Asia
6.
PLoS One ; 18(3): e0282740, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36867629

RESUMEN

Individuals with an objective decrease in salivary flow (objective dry mouth) may not be aware of subjective dry mouth (xerostomia). However, no clear evidence exists to explain the discordance between subjective and objective dry mouth. Therefore, this cross-sectional study aimed to assess the prevalence of xerostomia and decreased salivary flow among community-dwelling elderly adults. In addition, this study assessed several potential demographic and health status determinants of the discrepancy between xerostomia and reduced salivary flow. The 215 participants in this study were community-dwelling older people aged 70 years and above who underwent dental health examinations between January-February 2019. Symptoms of xerostomia were collected in the form of a questionnaire. The unstimulated salivary flow rate (USFR) was measured by a dentist using visual inspection. The stimulated salivary flow rate (SSFR) was measured using the Saxon test. We identified 19.1% of participants as having mild-severe USFR decline with xerostomia and 19.1% as having mild-severe USFR decline without xerostomia. Additionally, 26.0% of participants had low SSFR and xerostomia, and 40.0% had low SSFR without xerostomia. Except for the age trend, no factors could be associated with the discordance between USFR measurement and xerostomia. Furthermore, no significant factors were associated with the discordance between the SSFR and xerostomia. However, females were significantly associated (OR = 2.608, 95% CI = 1.174-5.791) with low SSFR and xerostomia, as compared to males. Age was a factor that was also significantly associated (OR = 1.105, 95% CI = 1.010-1.209) with low SSFR and xerostomia. Our findings indicate that approximately 20% of the participants had low USFR without xerostomia, and 40% had low SSFR without xerostomia. This study showed that age, sex, and the number of medications may not be factors in the discrepancy between the subjective feeling of dry mouth and reduced salivary flow.


Asunto(s)
Vida Independiente , Xerostomía , Anciano , Femenino , Masculino , Humanos , Japón , Estudios Transversales , Concienciación
7.
Artículo en Inglés | MEDLINE | ID: mdl-36554840

RESUMEN

The aim was to examine the relationships between oral functions and support/care-need certification in older people aged ≥ 75 years using the National Health Insurance (NHI) database system and data from Kani City, Gifu, Japan. In total, 732 older Japanese people aged ≥ 75 years who did not have support/care-need certification and underwent dental check-ups in Kani City in 2017 were followed up until 2020. Chewing state, tongue and lip function, and swallowing function were assessed by a self-administered questionnaire, an oral diadochokinesis test, and a repetitive saliva-swallowing test, respectively. The presence or absence of systemic diseases and of support/care-need certification was based on data collected by the NHI database. At follow up, 121 (17%) participants had support/care-need certification. The participants with support/care-need certification included more women (p < 0.001) and older people (p < 0.001); and had more hypertension (p = 0.003), musculoskeletal disorders (p < 0.001), pneumonia (p = 0.044), poor chewing state (p < 0.001), and poor swallowing function (p = 0.003) than those without support/care-need certification. Furthermore, the presence of support/care-need certification at follow up was associated with sex (woman: odds ratio [OR], 2.120; 95% confidence interval [CI], 1.354 to 3.317), age (OR, 1.203; CI, 1.139 to 1.270), chewing state (poor: OR, 2.534; CI, 1.409 to 4.557), and swallowing function (poor: OR, 2.372; CI, 1.248 to 4.510) at baseline. However, tongue and lip function were not associated with support/care-need certification. The results indicate that older Japanese people aged ≥ 75 years with a poor chewing state and poor swallowing function at baseline had a higher risk for support/care-need certification after three years.


Asunto(s)
Trastornos de Deglución , Pueblos del Este de Asia , Humanos , Femenino , Anciano , Estudios de Cohortes , Deglución , Lengua , Japón
8.
Sci Rep ; 10(1): 15108, 2020 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-32958815

RESUMEN

The bulk photovoltaic effect (BPVE) is a mechanism of recent focus for novel solar cells that exceed the power conversion efficiency of p-n junction solar cells because of the quantum mechanical effect to generate photocurrent known as shift current. Ferroelectrics are receiving attention again because of their high voltage generation by the BPVE and converse piezoelectric effect to realize high performance optical actuators. We have investigated the BPVE in ferroelectric BiFeO3 (BFO) single crystal thin films, whereby the photovoltage was enhanced by Mn doping, and 852 V generation was demonstrated at 80 K. The enhancement mechanism was also investigated using soft and hard X-ray photoelectron spectroscopy (SXPES, HAXPES), and soft X-ray absorption spectroscopy with synchrotron radiation. This report reveals a way to new voltage source applications employing the BPVE for high impedance devices with ferroelectrics. Important aspects for designing ferroelectric materials by impurity doping are also discussed.

9.
ACS Omega ; 5(11): 6090-6099, 2020 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-32226892

RESUMEN

An inexpensive, simple, and high-activity catalyst preparation method has been introduced in this work. Pt and RuO x catalysts were fabricated by soaking inexpensive graphite electrodes (pencil-lead graphite rod: PGR) in catalyst precursor solutions and using a simple flame-annealing method, which results in lower amount of Pt and RuO x catalyst layers. From X-ray photoelectron spectroscopy and near-edge X-ray absorption fine structure analysis, it has been found that platinum and ruthenium were deposited as zero-valence metal (Pt) and oxide (RuO x ), respectively. Catalytic activities of Pt/PGR and RuO x /PGR for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) were evaluated using neutral 1 M Na2SO4 aqueous electrolyte, respectively. Although HER and OER currents using PGR without catalysts were -16 mA cm-2 (at -1.5 V vs Ag/AgCl) and +20 mA cm-2 (at +2.0 V vs Ag/AgCl), they were improved to -110 and +80 mA cm-2 with catalysts (Pt and RuO x ), respectively. Such an inexpensive and rapid catalyst electrode preparation method on PGR using flame-annealing is a very significant method in the initial catalyst activity evaluation requiring a large amount of trial and error.

10.
Biomaterials ; 32(5): 1387-95, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21093041

RESUMEN

For development of tumor-specific chemotherapy, we designed liposomes with temperature-triggered drug release and magnetic resonance imaging (MRI) functions. We prepared multi-functional liposomes by incorporating thermosensitive poly(2-ethoxy(ethoxyethyl)vinyl ether) chains with a lower critical solution temperatures around 40 °C and polyamidoamine G3 dendron-based lipids having Gd(3+) chelate residues into pegylated liposomes. These stable doxorubicin (DOX)-loaded liposomes retained DOX in their interior below physiological temperature but released DOX immediately at temperatures greater than 40 °C. They exhibited excellent ability to shorten the longitudinal proton relaxation time. When administered intravenously into colon 26 tumor-bearing mice, accumulated liposomes in tumors increased with time, reaching a constant level 8 h after administration by following T(1)-weighted MRI signal intensity in tumors. Liposome size affected the liposome accumulation efficiency in tumors: liposomes of about 100 nm diameter were accumulated more efficiently than those with about 50 nm diameter. Tumor size also affected accumulation: more efficient accumulation occurred in larger tumors. Tumor growth was strongly suppressed when liposomes loaded with DOX were administered intravenously into tumor-bearing mice and the tumor was heated mildly at 44 °C for 10 min at 8 h after administration. Multi-functional liposomes having temperature-triggered drug release and MRI functions might engender personalized chemotherapy, providing efficient patient-optimized chemotherapy.


Asunto(s)
Portadores de Fármacos/administración & dosificación , Portadores de Fármacos/química , Liposomas/administración & dosificación , Liposomas/química , Temperatura , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Doxorrubicina/administración & dosificación , Doxorrubicina/uso terapéutico , Femenino , Imagen por Resonancia Magnética , Ratones , Ratones Endogámicos BALB C , Polímeros/química
11.
Clin Exp Pharmacol Physiol ; 30(4): 284-8, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12680848

RESUMEN

1. The effect of dietary Angelica keiskei on lipid metabolism was examined in stroke-prone spontaneously hypertensive rats (SHRSP). 2. Six-week-old male SHRSP were fed diets containing 0.2% A. keiskei extract (ethyl acetate extract from the yellow liquid of stems) for 6 weeks with free access to the diet and water. 3. Elevation of systolic blood pressure tended to be suppressed on and after 2 weeks; however, this effect was not statistically significant. 4. Serum levels of cholesterol and phospholipid in SHRSP were significantly elevated after treatment with A. keiskei extract and this effect was accompanied by significant increases in serum apolipoprotein (Apo) A-I and ApoE concentrations. These changes in the serum were due to increases in high-density lipoprotein (HDL) containing ApoA-I and ApoE. 5. In the liver, significant decreases in relative weight and triglyceride content were observed in SHRSP after treatment with A. keiskei extract. An investigation of mRNA expression of enzymes involved in hepatic triglyceride metabolism indicated a decreased level of hepatic Acyl-coenzyme A synthetase mRNA expression. 6. In conclusion, dietary A. keiskei produces elevation of serum HDL levels and a reduction of liver triglyceride levels in SHRSP.


Asunto(s)
Angelica , Dieta , Metabolismo de los Lípidos , Acetatos , Animales , Presión Sanguínea/efectos de los fármacos , Coenzima A Ligasas/antagonistas & inhibidores , Hiperlipidemias/metabolismo , Hipertensión/metabolismo , Hipertensión/fisiopatología , Lípidos/sangre , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología , Tallos de la Planta , ARN Mensajero/biosíntesis , Ratas , Ratas Endogámicas SHR , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Soluciones
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