Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 51
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Eur Neurol ; 86(4): 242-249, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37068470

RESUMEN

INTRODUCTION: Respiratory dysfunction in patients with Parkinson's disease (PD) could present in the early stage and worsen in the late stages. These changes could be a factor affecting the ability of daily living and quality of life of patients with PD. The primary objective of this study was to assess the respiratory function and its association with motor function in patients with different stages of PD. METHODS: This was a cross-sectional study conducted at the Huashan Hospital of Fudan University in Shanghai, China. The study included 65 patients diagnosed with PD (the Hoehn and Yahr scale between 1 and 4) and 20 healthy individuals of similar age, gender, weight, and height. The ventilatory function was assessed using the spirometry. Motor function was evaluated using subscale III of the United Parkinson's disease rating scale (UPDRS-III). After confirming the normality of data distribution, we performed one-way ANOVA with a Tukey's post hoc test. RESULTS: Compared with the healthy individuals, there was no statistical significance in forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), and forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) in the H&Y 1 group and H&Y 2 group (p > 0.05) but reduced peak expiratory flow (PEF) in the H&Y 2 group (p = 0.002). Reduced FVC, FEV1, and PEF was seen in the H&Y 3 group (p = 0.002, p = 0.001, and p = 0.0001, respectively). Reduced FVC, FEV1, PEF, and FEF25-75% was seen in the H&Y 4 group (p = 0.001, p = 0.0001, p = 0.0001, and p = 0.025, respectively). The correlation analysis revealed that there was a significant negative correlation between FVC and UPDRS-III scores (r = -0.248, p = 0.046), disease duration (r = -0.276, p = 0.026), H&Y scale (r = -0.415, p = 0.001). FEV1 was negatively correlated with UPDRS-III scores (r = -0.277, p = 0.025), disease duration (r = -0.291, p = 0.019), H&Y scale (r = -0.434, p = 0.0001). FEF25-75% was negatively correlated with disease duration (r = -0.247, p = 0.047), H&Y scale (r = -0.278, p = 0.025). CONCLUSION: Our findings revealed that respiratory impairment is present in moderate and advanced PD patients, and directly related to the severity of the disease. It is important to conduct respiratory function test in the clinical practice.


Asunto(s)
Enfermedad de Parkinson , Calidad de Vida , Humanos , Enfermedad de Parkinson/complicaciones , Estudios Transversales , China , Pruebas de Función Respiratoria
2.
Clin Oral Investig ; 27(7): 3961-3972, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37071219

RESUMEN

OBJECTIVES: The purpose of this study was to develop a novel Bonwill⁃Hawley method (Bonwill⁃Hawley arch form based on CBCT image) for the assessment of dental crowding, and to investigate and compare the accuracy and eligibility with the conventional brass wire and caliper methods under different crowding conditions. MATERIAL AND METHODS: Sixty patients with the pair of plaster casts and CBCT data were collected. All the casts were marked and transformed into digital models using iTero scanner, and imported into OrthoCAD software to measure the required space. Using the conventional brass wire (M1) and caliper methods (M2), the available space and dental crowding were measured and calculated basing on digital models, respectively. Correspondingly, the axial planes in the level of dental arches were oriented and captured from the CBCT images to draw the Bonwill⁃Hawley arch forms (M3), which were used to measure and calculate the available space and dental crowding. For each method, intra and inter-examiner reliabilities were evaluated with intra-class correlation coefficients (ICCs). Wilcoxon test and Kruskal-Wallis test were performed for statistically analyzing the discrepancy among different groups. RESULTS: Both intra- and inter-examiner reliability were generally excellent for all parameters obtained by the three methods, except for the dental crowding measured using M1(ICC: 0.473/0.261). The dental crowding measured using M2 were significantly increased in mild, moderate and severe-crowding groups compared with M1. However, no significant difference was detected between M1 and M3 in severe-crowding group (maxilla, p = 0.108 > 0.05; mandible, p = 0.074 > 0.05). With the deterioration of crowding condition, the discrepancy of dental crowding between M1 and M2, or M1 and M3 were significantly decreased (maxilla, M2-M1, mild VS serve, p = 0.003 < 0.05; maxilla, M3-M1, mild VS serve, p = 0.003 < 0.05; mandible, M2-M1, mild VS serve, p = 0.000 < 0.001; mandible, M3-M1, mild VS serve, p = 0.043 < 0.05). CONCLUSION: Dental crowding measured using the novel Bonwill⁃Hawley method was relatively greater than the caliper method, but not exceeding the brass wire method, which wound gradually come close to the brass wire method with the deterioration of crowding condition. CLINICAL RELEVANCE: The Bonwill⁃Hawley method basing on CBCT image proved to be a reliable and acceptable choice for orthodontists to analyze the dental crowding.


Asunto(s)
Tomografía Computarizada de Haz Cónico Espiral , Humanos , Reproducibilidad de los Resultados , Cobre , Zinc , Mandíbula , Maxilar , Arco Dental/diagnóstico por imagen , Imagenología Tridimensional/métodos
3.
Biochem Biophys Res Commun ; 511(1): 41-48, 2019 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-30765221

RESUMEN

High fat diet (HFD)-induced obesity is associated with insulin resistance (IR) and other chronic, diet associated illnesses, including neuroinflammation and brain injury. However, the involvement of inflammatory response in HFD-elicited central nerve injury has yet to be fully determined. Recent studies have indicated that tumor necrosis factor receptor-associated ubiquitous scaffolding and signaling protein (TRUSS), also known as TRPC4AP, plays an essential role in regulating inflammation via the meditation of NF-κB signaling. In the present study, we attempted to explore the effects of TRUSS on HFD-induced brain injury in the wild type mice (TRUSS+/+) or TRUSS-knockout mice (TRUSS-/-). The results suggested that TRUSS deletion attenuated HFD-induced cognitive impairments in mice. HFD-elicited metabolic disorders were also highly improved by the loss of TRUSS, as evidenced by the reduced serum glucose and insulin levels, as well as the lipid deposition in liver tissues. In addition, HFD-triggered brain injury was markedly alleviated by the TRUSS ablation, as proved by the reduction of GFAP and Iba1 expressions in hippocampus and hypothalamus. Moreover, TRUSS-/- mice exhibited a significant decrease in the expression of pro-inflammatory cytokines, accompanied with the inactivation of IKKα/IκBα/NF-κB pathway. At the same time, HFD-induced dyslipidemia was also alleviated by the loss of TRUSS. The in vitro study verified the protective effects of TRUSS-suppression against HFD-induced central nerve injury and hepatic steatosis by restraining the inflammatory response. In summary, our data indicated that TRUSS participated in metabolic syndrome-induced brain injury and pointed to the repression of TRUSS as a promising strategy for cognitive deficits therapy.


Asunto(s)
Lesiones Encefálicas/genética , Disfunción Cognitiva/genética , Dieta Alta en Grasa/efectos adversos , Eliminación de Gen , Inflamación/genética , Transactivadores/genética , Animales , Lesiones Encefálicas/etiología , Lesiones Encefálicas/patología , Células Cultivadas , Disfunción Cognitiva/etiología , Disfunción Cognitiva/patología , Hipocampo/metabolismo , Hipocampo/patología , Hipotálamo/metabolismo , Hipotálamo/patología , Inflamación/etiología , Inflamación/patología , Masculino , Ratones Endogámicos C57BL , Factores Protectores
4.
Environ Sci Technol ; 52(7): 4275-4284, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29513011

RESUMEN

Efficient oxidation from arsenite [As(III)] to arsenate [As(V)], which is less toxic and more readily to be adsorbed by adsorbents, is important for the remediation of arsenic pollution. In this paper, we report a metal organic framework (MIL-100(Fe)) filter to efficiently remove arsenic from synthetic groundwater. With commercially available iron mesh as a substrate, MIL-100(Fe) is implanted through an in situ growth method. MIL-100(Fe) is able to capture As(III) due to its microporous structure, superior surface area, and ample active sites for As adsorption. This approach increases the localized As concentration around the filter, where Fenton-like reactions are initiated by the Fe2+/Fe3+ sites within the MIL-100(Fe) framework to oxidize As(III) to As(V). The mechanism was confirmed by colorimetric detection of H2O2, fluorescence, and electron paramagnetic resonance detection of ·OH. With the aid of oxygen bubbling and Joule heating, the removal efficiency of As(III) can be further boosted. The MIL-100(Fe)-based filter also exhibits satisfactory structural stability and recyclability. Notably, the adsorption capacity of the filter can be regenerated satisfactorily. Our results demonstrate the potential of this filter for the efficient remediation of As contamination in groundwater.


Asunto(s)
Arsénico , Estructuras Metalorgánicas , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Peróxido de Hidrógeno , Hierro , Mallas Quirúrgicas
5.
Environ Sci Technol ; 49(11): 6846-54, 2015 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-25942505

RESUMEN

In this work, we describe multifunctional, crumpled graphene oxide (CGO) porous nanocomposites that are assembled as advanced, reactive water treatment membranes. Crumpled 3D graphene oxide based materials fundamentally differ from 2D flat graphene oxide analogues in that they are highly aggregation and compression-resistant (i.e., π-π stacking resistant) and allow for the incorporation (wrapping) of other, multifunctional particles inside the 3D, composite structure. Here, assemblies of nanoscale, monomeric CGO with encapsulated (as a quasi core-shell structure) TiO2 (GOTI) and Ag (GOAg) nanoparticles, not only allow high water flux via vertically tortuous nanochannels (achieving water flux of 246 ± 11 L/(m(2)·h·bar) with 5.4 µm thick assembly, 7.4 g/m(2)), outperforming comparable commercial ultrafiltration membranes, but also demonstrate excellent separation efficiencies for model organic and biological foulants. Further, multifunctionality is demonstrated through the in situ photocatalytic degradation of methyl orange (MO), as a model organic, under fast flow conditions (tres < 0.1 s); while superior antimicrobial properties, evaluated with GOAg, are observed for both biofilm (contact) and suspended growth scenarios (>3 log effective removal, Escherichia coli). This is the first demonstration of 3D, crumpled graphene oxide based nanocomposite structures applied specifically as (re)active membrane assemblies and highlights the material's platform potential for a truly tailored approach for next generation water treatment and separation technologies.


Asunto(s)
Grafito/química , Membranas Artificiales , Nanocompuestos/química , Nanotecnología/métodos , Purificación del Agua/métodos , Catálisis/efectos de la radiación , Recuento de Colonia Microbiana , Escherichia coli/crecimiento & desarrollo , Luz , Pruebas de Sensibilidad Microbiana , Nanocompuestos/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Titanio/química , Ultrafiltración
6.
J Air Waste Manag Assoc ; 65(4): 455-65, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25947215

RESUMEN

UNLABELLED: Corona discharge based techniques are promising approaches for oxidizing elemental mercury (Hg0) in flue gas from coal combustion. In this study, in-situ soft X-rays were coupled to a DC (direct current) corona-based electrostatic precipitator (ESP). The soft X-rays significantly enhanced Hg0 oxidation, due to generation of electrons from photoionization of gas molecules and the ESP electrodes. This coupling technique worked better in the positive corona discharge mode because more electrons were in the high energy region near the electrode. Detailed mechanisms of Hg0 oxidation are proposed and discussed based on ozone generation measurements and Hg0 oxidation behavior observations in single gas environments (O2, N2, and CO2). The effect of O2 concentration in flue gas, as well as the effects of particles (SiO2, TiO2, and KI) was also evaluated. In addition, the performance of a soft X-rays coupled ESP in Hg0 oxidations was investigated in a lab-scale coal combustion system. With the ESP voltage at +10 kV, soft X-ray enhancement, and KI addition, mercury oxidation was maximized. IMPLICATIONS: Mercury is a significant-impact atmospheric pollutant due to its toxicity. Coal-fired power plants are the primary emission sources of anthropogenic releases of mercury; hence, mercury emission control from coal-fired power plant is important. This study provides an alternative mercury control technology for coal-fired power plants. The proposed electrostatic precipitator with in situ soft X-rays has high efficiency on elemental mercury conversion. Effects of flue gas conditions (gas compositions, particles, etc.) on performance of this technology were also evaluated, which provided guidance on the application of the technology for coal-fired power plant mercury control.


Asunto(s)
Contaminantes Atmosféricos/química , Mercurio/química , Electricidad Estática , Ceniza del Carbón/química , Gases/química , Oxidación-Reducción , Material Particulado/química , Centrales Eléctricas , Rayos X
7.
Anal Chem ; 86(15): 7523-9, 2014 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-24968004

RESUMEN

Measuring stable clusters to understand particle inception will aid the synthesis of well-controlled nanoparticles via gas-phase aerosol routes. Using a Half Mini differential mobility analyzer, the presence of monomers, dimers, trimers, and tetramers was detected for the first time in a flame aerosol reactor during the synthesis of pristine TiO2 and TiO2/SiO2 nanocomposites. Atomic force microscopy confirmed the presence and the size of sub-2 nm clusters. The detection of these clusters elucidated the initial stages of particle formation during combustion synthesis and supported previous hypotheses that collisional growth from stable monomers of metal oxides is the first step of particle growth.

8.
Langmuir ; 30(38): 11257-62, 2014 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-25211031

RESUMEN

A facile method for designing and synthesizing nanostructured carbon particles via ultrasonic spray pyrolysis of a self-organized dual polymer system comprising phenolic resin and charged polystyrene latex is reported. The method produces either hollow carbon particles, whose CO2 adsorption capacity is 3.0 mmol g(-1), or porous carbon particles whose CO2 adsorption capacity is 4.8 mmol g(-1), although the two particle types had similar diameters of about 360 nm. We investigate how the zeta potential of the polystyrene latex particles, and the resulting electrostatic interaction with the negatively charged phenolic resin, influences the particle morphology, pore structure, and CO2 adsorption capacity.


Asunto(s)
Carbono/química , Formaldehído/química , Nanoestructuras/química , Fenoles/química , Polímeros/química , Poliestirenos/química , Adsorción , Aerosoles/síntesis química , Aerosoles/química , Dióxido de Carbono/química , Tamaño de la Partícula , Porosidad , Propiedades de Superficie
9.
Environ Eng Sci ; 31(7): 428-434, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25053879

RESUMEN

Photocatalytic reduction of carbon dioxide (CO2) to hydrocarbons by using nanostructured materials activated by solar energy is a promising approach to recycling CO2 as a fuel feedstock. CO2 photoreduction, however, suffers from low efficiency mainly due to the inherent drawback of fast electron-hole recombination in photocatalysts. This work reports the synthesis of nanostructured composites of titania (TiO2) nanoparticles (NPs) encapsulated by reduced graphene oxide (rGO) nanosheets via an aerosol approach. The role of synthesis temperature and TiO2/GO ratio in CO2 photoreduction was investigated. As-prepared nanocomposites demonstrated enhanced CO2 conversion performance as compared with that of pristine TiO2 NPs due to the strong electron trapping capability of the rGO nanosheets.

10.
J Invest Dermatol ; 144(1): 133-141.e4, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37301319

RESUMEN

Neurofibromatosis 1 is a prevalent hereditary neurocutaneous disorder. Among the clinical phenotypes of neurofibromatosis 1, cutaneous neurofibroma (cNF) and plexiform neurofibroma (pNF) have distinct clinical manifestations, and pNF should be closely monitored owing to its malignant potential. However, the detailed distinct features of neurofibromatosis 1 phenotypes remain unknown. To determine whether the transcriptional features and microenvironment of cNF and pNF differ, single-cell RNA sequencing was performed on isolated cNF and pNF cells from the same patient. Six cNF and five pNF specimens from different subjects were also immunohistochemically analyzed. Our findings revealed that cNF and pNF had distinct transcriptional profiles even within the same subject. pNF is enriched in Schwann cells with characteristics similar to those of their malignant counterpart, fibroblasts, with a cancer-associated fibroblast-like phenotype, angiogenic endothelial cells, and M2-like macrophages, whereas cNF is enriched in CD8 T cells with tissue residency markers. The results of immunohistochemical analyses performed on different subjects agreed with those of single-cell RNA sequencing. This study found that cNF and pNF, the different neurofibromatosis phenotypes in neurofibromatosis 1, from the same subject are transcriptionally distinct in terms of the cell types involved, including T cells.


Asunto(s)
Neurofibroma Plexiforme , Neurofibroma , Neurofibromatosis 1 , Neoplasias Cutáneas , Humanos , Células Endoteliales/metabolismo , Neurofibroma/genética , Neurofibroma/complicaciones , Neurofibroma/metabolismo , Neurofibroma Plexiforme/genética , Neurofibromatosis 1/genética , Neoplasias Cutáneas/metabolismo , Microambiente Tumoral
11.
Tumour Biol ; 34(3): 1865-71, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23519840

RESUMEN

Gastric cancer is the second leading cause of cancer mortality, but the molecular mechanisms underlying its progression and metastasis remain unclear. CCR7 and Dicer 1 protein expression in 80 gastric adenocarcinomas and 40 peritumoral tissues were measured by immunohistochemical staining. The expression of let-7a miRNA in serum, tumor tissues, and peritumoral tissues was measured by real-time PCR. The role of let-7a in CCR7 protein expression, migration, and invasion of gastric cancer cells was tested in vitro. Dicer 1 protein expression was found to be significantly reduced, whereas CCR7 protein expression was significantly increased in gastric adenocarcinomas compared to peritumoral tissues. The let-7a miRNA levels in the serum and tumor tissues of gastric adenocarcinoma patients were significantly lower than in the serum of healthy controls and peritumoral tissues, respectively. Dicer 1 protein positively correlated with let-7a miRNA level, but negatively correlated with CCR7 protein level in gastric adenocarcinoma. Negative Dicer 1 protein and let-7a miRNA expression and positive CCR7 protein expression significantly correlated with lymph node metastasis, depth of invasion, high clinical TNM stage, and larger tumor size. Let-7a transfection significantly inhibited CCR7 protein expression, migration, and invasion of MNK-45 cells in vitro. High expression of CCR7 protein and low expression of Dicer 1 protein and let-7a miRNA are significantly associated with the metastasis and progression of gastric cancer. High CCR7 protein expression may be caused by the loss of Dicer 1 protein expression and reduced let-7a miRNA level in gastric cancer. The serum let-7a level might be a marker for the diagnosis of gastric cancer.


Asunto(s)
Adenocarcinoma/patología , Movimiento Celular , Proliferación Celular , ARN Helicasas DEAD-box/genética , MicroARNs/genética , Receptores CCR7/genética , Ribonucleasa III/genética , Neoplasias Gástricas/patología , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adulto , Anciano , Western Blotting , Diferenciación Celular , ARN Helicasas DEAD-box/metabolismo , Femenino , Humanos , Técnicas para Inmunoenzimas , Metástasis Linfática , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Pronóstico , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores CCR7/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ribonucleasa III/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
12.
J Nanosci Nanotechnol ; 13(3): 2376-81, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23755694

RESUMEN

N-doped TiO2 nanoparticles were synthesized using a hydrazine-assisted liquid method at low temperatures, owing to the additional heat provided by the decomposition of hydrazine nitrate, which was formed by reaction of hydrazine with nitric acid. Different crystal phases of N-doped TiO2 were studied by varying the nitric acid concentration, and calcination temperature and time. These photocatalysts were characterized using a transmission electron microscope, UV-vis photometer, X-ray diffractometer, and nitrogen adsorption. Photocatalytic performance of the N-doped TiO2 was studied by testing the degradation of methyl orange under visible irradiation. It was observed that N-doped TiO2 demonstrated much higher photocatalytic performance than commercial TiO2 (P-25) and exhibited excellent reusability.

13.
J Colloid Interface Sci ; 639: 203-213, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36805745

RESUMEN

Electrospray is an effective, fast, and potentially scalable approach for membrane surface functionalization using various engineered nanomaterials (ENMs). However, the lack of fundamental understandings of the deposition process hinders the controlled deposition, efficient utilization, and long-term stabilization of the ENMs, and thus the practical applications of the nanocomposite membranes. To bridge this critical knowledge gap, advanced online characterization techniques (laser diffraction size measurement and laser doppler velocimetry) coupled with mathematical aerosol modeling are utilized to understand the three key process parameters: droplet size, deposition velocity, and evaporation rate. After deposition, polymeric solvent bonding (i.e., interdiffusion and subsequent entanglement of polymers) was found to substantially stabilize the deposited Ag NPs. We further provide a comprehensive description of such interfacial reaction mechanisms. Our results show a consistency between theoretical predication and measurement of the droplet size or deposition velocity, whereas realistic droplet evaporation rate is lower than the theoretical value due to the addition of the polymer. Successful stabilization of Ag NPs via interfacial polymeric bonding occurs under the conditions of large material contact area, high material compatibility, proper temperature (e.g., 22 °C), and polymer-to-solvent ratio (e.g., 3-5%). Our coupled approach achieves superior Ag NP coverage with high stability within minutes. Despite some reduction in water permeance, the resultant membrane shows markedly improved catalytic and antimicrobial (antibiofouling) performance (>90% enhancement) and maintained rejection. Taken together, our findings provide fundamental insights into the coupled process of electrospray deposition and polymeric solvent bonding to enable additive manufacturing of novel nanocomposite membranes with diverse structures and multiple functions.

14.
Parkinsons Dis ; 2023: 9175129, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37333719

RESUMEN

Background: Archery exercise exerts a rehabilitative effect on patients with paraplegia and might potentially serve as complementary physiotherapy for patients with Parkinson's disease. Objective: This study aimed to examine the rehabilitative effects of an archery intervention. Methods: A randomized controlled trial of a 12-week intervention was performed in patients with idiopathic Parkinson's disease. Thirty-one of the 39 eligible patients recruited from a medical center in Taiwan participated in the trial, of whom 16 were in the experimental group practicing archery exercises and 15 were in the control group at the beginning; twenty-nine completed the whole process. The Purdue pegboard test (PPT), the Unified Parkinson's Disease Rating Scale I to III (UPDRS I to III), physical fitness test, and timed up and go test (TUG) were used to assess the intervention effects of archery exercise. Results: Compared to the control group, the outcome differences between the posthoc and baseline tests in PPT, UPDRS I to III, lower extremity muscular strength, and TUG in the experimental group (between-group difference in difference's mean: 2.07, 1.59, 1.36, -2.25, -3.81, -9.10, 3.57, and -1.51, respectively) did show positive changes and their effect sizes examined from Mann-Whitney U tests (η: 0.631, 0.544, 0.555, 0.372, 0.411, 0.470, 0.601, and 0.381, respectively; Ps < 0.05) were medium to large, indicating that the archery intervention exerted promising effects on improving hand flexibility and finger dexterity, activity functions in motor movement, lower extremity muscular strength, and gait and balance ability. Conclusions: Traditional archery exercise was suggested to have a rehabilitative effect for mild to moderate Parkinson's disease and could be a form of physiotherapy. Nevertheless, studies with larger sample sizes and extended intervention periods are needed to ascertain the long-term effects of archery exercise.

15.
J Am Chem Soc ; 134(27): 11276-81, 2012 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-22694165

RESUMEN

A facile development of highly efficient Pt-TiO(2) nanostructured films via versatile gas-phase deposition methods is described. The films have a unique one-dimensional (1D) structure of TiO(2) single crystals coated with ultrafine Pt nanoparticles (NPs, 0.5-2 nm) and exhibit extremely high CO(2) photoreduction efficiency with selective formation of methane (the maximum CH(4) yield of 1361 µmol/g-cat/h). The fast electron-transfer rate in TiO(2) single crystals and the efficient electron-hole separation by the Pt NPs were the main reasons attributable for the enhancement, where the size of the Pt NPs and the unique 1D structure of TiO(2) single crystals played an important role.

16.
Langmuir ; 28(19): 7528-34, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22506676

RESUMEN

Two novel deposition methods were used to synthesize Pt-TiO(2) composite photoelectrodes: a tilt-target room temperature sputtering method and aerosol-chemical vapor deposition (ACVD). Pt nanoparticles (NPs) were sequentially deposited by the tilt-target room temperature sputtering method onto the as-synthesized nanostructured columnar TiO(2) films by ACVD. By varying the sputtering time of Pt deposition, the size of deposited Pt NPs on the TiO(2) film could be precisely controlled. The as-synthesized composite photoelectrodes with different sizes of Pt NPs were characterized by various methods, such as SEM, EDS, TEM, XRD, and UV-vis. The photocurrent measurements revealed that the modification of the TiO(2) surface with Pt NPs improved the photoelectrochemical properties of electrodes. Performance of the Pt-TiO(2) composite photoelectrodes with sparsely deposited 1.15 nm Pt NPs was compared to the pristine TiO(2) photoelectrode with higher saturated photocurrents (7.92 mA/cm(2) to 9.49 mA/cm(2)), enhanced photoconversion efficiency (16.2% to 21.2%), and increased fill factor (0.66 to 0.70). For larger size Pt NPs of 3.45 nm, the composite photoelectrode produced a lower photocurrent and reduced conversion efficiency compared to the pristine TiO(2) electrode. However, the surface modification by Pt NPs helped the composite electrode maintain higher fill factor values.

17.
Nanotechnology ; 22(41): 415704, 2011 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-21918299

RESUMEN

The properties of Cu-doped TiO(2) nanoparticles (NPs) were independently controlled in a flame aerosol reactor by varying the molar feed ratios of the precursors, and by optimizing temperature and time history in the flame. The effect of the physico-chemical properties (dopant concentration, crystal phase and particle size) of Cu-doped TiO(2) nanoparticles on inactivation of Mycobacterium smegmatis (a model pathogenic bacterium) was investigated under three light conditions (complete dark, fluorescent light and UV light). The survival rate of M. smegmatis (in a minimal salt medium for 2 h) exposed to the NPs varied depending on the light irradiation conditions as well as the dopant concentrations. In dark conditions, pristine TiO(2) showed insignificant microbial inactivation, but inactivation increased with increasing dopant concentration. Under fluorescent light illumination, no significant effect was observed for TiO(2). However, when TiO(2) was doped with copper, inactivation increased with dopant concentration, reaching more than 90% (>3 wt% dopant). Enhanced microbial inactivation by TiO(2) NPs was observed only under UV light. When TiO(2) NPs were doped with copper, their inactivation potential was promoted and the UV-resistant cells were reduced by over 99%. In addition, the microbial inactivation potential of NPs was also crystal-phase-and size-dependent under all three light conditions. A lower ratio of anatase phase and smaller sizes of Cu-doped TiO(2) NPs resulted in decreased bacterial survival. The increased inactivation potential of doped TiO(2) NPs is possibly due to both enhanced photocatalytic reactions and leached copper ions.


Asunto(s)
Antibacterianos/química , Cobre/química , Viabilidad Microbiana/efectos de los fármacos , Mycobacterium smegmatis/efectos de los fármacos , Nanopartículas/química , Titanio/química , Antibacterianos/farmacología , Cobre/farmacología , Humanos , Viabilidad Microbiana/efectos de la radiación , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Mycobacterium smegmatis/efectos de la radiación , Nanopartículas/ultraestructura , Tamaño de la Partícula , Titanio/farmacología , Rayos Ultravioleta
18.
Inhal Toxicol ; 23(7): 407-16, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21639709

RESUMEN

We evaluated the pulmonary pathological features of rats that received a single intratracheal instillation and a 4-week inhalation of a fullerene. We used fullerene C(60) (nanom purple; Frontier Carbon Co. Ltd, Japan) in this study. Male Wistar rats received intratracheal dose of 0.1, 0.2, or 1 mg of C(60), and were sacrificed at 3 days, 1 week, 1 month, 3 months, 6 months, and 12 months. In the inhalation study, Wistar rats received C(60) or nickel oxide by whole-body inhalation for 6 h/day, 5 days/week, 4 weeks, and were sacrificed at 3 days, 1 month, and 3 months after the end of exposure. During the observation period, no tumors or granulomas were observed in either study. Histopathological evaluation by the point counting method (PCM) showed that a high dose of C(60) (1 mg) instillation led to a significant increase of areas of inflammation in the early phase (until 1 week). In the inhalation study of the C(60)-exposed group, PCM evaluation showed significant changes in the C(60)-exposed group only at 3 days after exposure; after 1 month, no significant changes were observed. The present study demonstrated that the pulmonary inflammation pattern after exposure to well-characterized C(60) via both intratracheal and inhalation instillation was slight and transient. These results support our previous studies that showed C(60) has no significant adverse effects in intratracheal and inhalation instillation studies.


Asunto(s)
Fulerenos/administración & dosificación , Exposición por Inhalación/efectos adversos , Lesión Pulmonar/inducido químicamente , Pulmón/efectos de los fármacos , Animales , Inflamación/inducido químicamente , Pulmón/patología , Masculino , Nanopartículas del Metal/química , Nivel sin Efectos Adversos Observados , Tamaño de la Partícula , Ratas , Ratas Wistar
19.
Inhal Toxicol ; 23(13): 784-91, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22035120

RESUMEN

It is important to conduct a risk assessment that includes hazard assessment and exposure assessment for the safe production and handling of newly developed nanomaterials. We conducted an inhalation study of a multi-wall carbon nanotube (MWCNT) as a hazard assessment. Male Wistar rats were exposed to well-dispersed MWCNT for 4 weeks by whole body inhalation. The exposure concentration in the chamber was 0.37 ± 0.18 mg/m³. About 70% of the MWCNTs in the chamber were single fiber. The geometric mean diameter (geometric standard deviation, GSD) and geometric mean length (GSD) of the aerosolized MWCNTs in the chamber were 63 nm (1.5) and 1.1 µm (2.7), respectively. The amounts of MWCNT deposited in the rat lungs were determined by the X-ray diffraction method and elemental carbon analysis. The average deposited amounts at 3 days after the inhalation were 68 µg/lung by the X-ray diffraction method and 76 µg/lung by elemental carbon analysis. The calculated deposition fractions were 18% and 20% in each analysis. The amount of retained MWCNT in the lungs until 3 months after the inhalation decreased exponentially and the calculated biological half times of MWCNT were 51 days and 54 days, respectively. The clearance was not delayed, but a slight increase in lung weight at 3 days after the inhalation was observed.


Asunto(s)
Pulmón/metabolismo , Nanotubos de Carbono , Administración por Inhalación , Animales , Pulmón/patología , Masculino , Ratas , Ratas Wistar , Distribución Tisular , Pruebas de Toxicidad Subaguda , Difracción de Rayos X
20.
Nutrients ; 13(9)2021 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-34579053

RESUMEN

Early enteral nutrition (EN) and a nutrition target >60% are recommended for patients in the intensive care unit (ICU), even for those with acute respiratory distress syndrome (ARDS). Prolonged prone positioning (PP) therapy (>48 h) is the rescue therapy of ARDS, but it may worsen the feeding status because it requires the heavy sedation and total paralysis of patients. Our previous studies demonstrated that energy achievement rate (EAR) >65% was a good prognostic factor in ICU. However, its impact on the mortality of patients with ARDS requiring prolonged PP therapy remains unclear. We retrospectively analyzed 79 patients with high nutritional risk (modified nutrition risk in the critically ill; mNUTRIC score ≥5); and identified factors associated with ICU mortality by using a Cox regression model. Through univariate analysis, mNUTRIC score, comorbid with malignancy, actual energy intake, and EAR (%) were associated with ICU mortality. By multivariate analysis, EAR (%) was a strong predictive factor of ICU mortality (HR: 0.19, 95% CI: 0.07-0.56). EAR >65% was associated with lower 14-day, 28-day, and ICU mortality after adjustment for confounding factors. We suggest early EN and increase EAR >65% may benefit patients with ARDS who required prolonged PP therapy.


Asunto(s)
Nutrición Enteral , Trastornos Nutricionales/prevención & control , Posición Prona , Síndrome de Dificultad Respiratoria/mortalidad , Anciano , Nutrición Enteral/métodos , Nutrición Enteral/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Nutricionales/mortalidad , Pronóstico , Síndrome de Dificultad Respiratoria/metabolismo , Síndrome de Dificultad Respiratoria/terapia , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA