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1.
Mol Cell ; 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37657444

RESUMEN

N6-methyladenosine (m6A) RNA modification plays important roles in the governance of gene expression and is temporally regulated in different cell states. In contrast to global m6A profiling in bulk sequencing, single-cell technologies for analyzing m6A heterogeneity are not extensively established. Here, we developed single-nucleus m6A-CUT&Tag (sn-m6A-CT) for simultaneous profiling of m6A methylomes and transcriptomes within a single nucleus using mouse embryonic stem cells (mESCs). m6A-CT is capable of enriching m6A-marked RNA molecules in situ, without isolating RNAs from cells. We adapted m6A-CT to the droplet-based single-cell omics platform and demonstrated high-throughput performance in analyzing nuclei isolated from thousands of cells from various cell types. We show that sn-m6A-CT profiling is sufficient to determine cell identity and allows the generation of cell-type-specific m6A methylome landscapes from heterogeneous populations. These indicate that sn-m6A-CT provides additional dimensions to multimodal datasets and insights into epitranscriptomic landscape in defining cell fate identity and states.

2.
BMC Oral Health ; 24(1): 187, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-38317203

RESUMEN

BACKGROUND: Mastication is important for breaking down food, aiding swallowing and nutrients absorption, and is therefore fundamental to a child's development. Studies have shown poor masticatory function to be associated with younger age and presence of caries. However, studies of the association between masticatory function and malocclusion yielded contradictory results. The aim of this study is therefore to investigate the association between three-dimensional occlusal features with masticatory function, among preschool children in Hong Kong. METHODS: Self-administered questionnaires on masticatory function in three domains, namely general chewing difficulty, requiring help when eating different food types and increased preference for soft food were completed by parents. Information on non-nutritive sucking habits and basic demographics were also collected in the questionnaire. Clinical examinations were conducted to record three-dimensional occlusal features and presence of caries. Baseline investigations and one-year follow-ups were undertaken for 1,566 and 996 preschool children. Association of poor masticatory function with occlusal features, sucking habits and caries was investigated using chi-squared tests. Binomial logistic regressions were then carried out incorporating any significant factors identified. Longitudinal analysis of the one-year follow-up data was carried out to investigate whether improved occlusal features, sucking habits and caries resulted in better masticatory function. RESULTS: In the cross-sectional study, the first domain of general chewing difficulty was associated with caries and thumb/digit sucking. The second domain of requiring help when eating different food types was associated with the male sex, younger age, caries and pacifier use. The last domain of increased preference for soft foods was associated with caries and thumb/digit sucking. Occlusal features, including abnormal overjet and unilateral permanent molars not in contact, were significantly associated with poor masticatory function in the bivariate analyses, but were not significant in the logistic regressions. In the longitudinal analysis, general chewing difficulty was found to improve in those of older age and those with resolved anterior crossbite. Less help was required to eat meat in those with fewer caries. Similarly, less help was required to eat food containing bones in those with reduced pacifier use. Preferences for eating soft foods was reduced in those who developed a normal overjet. CONCLUSIONS: The study identified significant relationships between masticatory difficulties and factors associated with age, gender, active caries, and non-nutritive oral habits such as thumb/digit sucking and pacifier use. Younger children and males required more assistance with certain food types. Active caries and thumb/digit sucking habits contributed to general masticatory difficulties and preference for soft foods. The one-year follow-up indicated that improvement in masticatory function varies across age cohorts and were associated with improved occlusal features, such as resolution of anterior crossbite and normalized overjet, reduced pacifier use, and a decrease in the number of decayed teeth.


Asunto(s)
Maloclusión , Humanos , Masculino , Preescolar , Hong Kong , Estudios de Seguimiento , Estudios Transversales , Succión del Dedo , Conducta en la Lactancia , Encuestas y Cuestionarios
3.
Phys Chem Chem Phys ; 24(9): 5748-5754, 2022 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35191434

RESUMEN

Deoxyribonucleic acid (DNA) sequencing has found wide applications in medicine including treatment of diseases, diagnosis and genetics studies. Rapid and cost-effective DNA sequencing has been achieved by measuring the transverse electronic conductance as a single-stranded DNA is driven through a nanojunction. With the aim of improving the accuracy and sensitivity of DNA sequencing, we investigate the electron transport properties of DNA nucleobases within gold nanogaps based on first-principles quantum transport simulations. Considering the fact that the DNA bases can rotate within the nanogap during measurements, different nucleobase orientations and their corresponding residence time within the nanogap are explicitly taken into account based on their energetics. This allows us to obtain an average current that can be compared directly to experimental measurements. Our results indicate that bare gold electrodes show low distinguishability among the four DNA nucleobases while the distinguishability can be substantially enhanced with sulfur atom decorated electrodes. We further optimized the size of the nanogap by maximizing the residence time of the desired orientation.


Asunto(s)
Nanoporos , ADN , Electrónica , Oro , Análisis de Secuencia de ADN/métodos
4.
Lasers Med Sci ; 35(3): 729-739, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31833004

RESUMEN

Low-level laser irradiation (LLLI) shows effects in orthodontic pain relief and periodontal inflammation control. The aim of this article is to investigate the analgesic and inflammation-modulatory effects of low-level laser irradiation among orthodontic patients with compromised periodontium. A randomised controlled trial with split-mouth design was conducted in 27 adults with treated and controlled chronic periodontitis over 6 months. One side of the dental arch underwent repeated treatment under a 940-nm diode laser (EZlase; Biolase Technology Inc.) with a beam size of 2.8 cm2 for 60 seconds at 8.6 J/cm2, whilst the other side received pseudo-laser treatment. Laser irradiation was applied repeatedly for 8 times during the first 6 weeks after bracket bonding and monthly thereafter until the end of orthodontic treatment. Subjective pain (assessed by visual analogue scale in pain diary and by chairside archwire activation), periodontal status (assessed by periodontal clinical parameters), cytokines in gingival crevicular fluid (interleukin 1ß, prostaglandin E2, substance P) and periodontopathic bacteria (Porphyromonas gingivalis and Treponema denticola) in supragingival plaque were assessed. The intensity of pain was lower on the laser-irradiated side at multiple follow-up visits (P < 0.05). The pain subsided 1 day earlier on the laser side, with a lower peak value during the first week after initial archwire placement (P < 0.05). The laser side exhibited a smaller reduction in bite force during the first month (mean difference = 3.17, 95% CI: 2.36-3.98, P < 0.05 at 1-week interval; mean difference = 3.09, 95% CI: 1.87-4.32, P < 0.05 at 1-month interval). A smaller increase was observed in the plaque index scores on the laser side at 1-month (mean difference = 0.19, 95% CI: 0.13-0.24, P < 0.05) and in the gingival index scores at the 3-month follow-up visit (mean difference = 0.18, 95% CI: 0.14-0.21, P < 0.05). Laser irradiation inhibited the elevation of interleukin-1ß, prostaglandin E2 and substance P levels during the first month (P < 0.05). However, no intergroup difference was detected in the bacteria levels. Low-level laser irradiation exhibits benefits in pain relief and inflammation control during the early stage of adjunctive orthodontic treatment in periodontally compromised individuals.


Asunto(s)
Periodontitis Crónica/radioterapia , Terapia por Luz de Baja Intensidad , Adulto , Carga Bacteriana , Biomarcadores/metabolismo , Femenino , Encía/microbiología , Líquido del Surco Gingival , Humanos , Masculino , Persona de Mediana Edad , Percepción del Dolor , Índice Periodontal , Porphyromonas gingivalis/fisiología , Escala Visual Analógica
5.
Mol Pharm ; 16(1): 195-204, 2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-30525643

RESUMEN

While flash nanoprecipitation (FNP) has proven to be an extremely rapid and highly efficient nanoparticle fabrication process for hydrophobic drugs, physical instability associated with nonequilibrium molecular orientation of amphiphilic stabilizers (ASs) in nanoparticles remains a major snag in the general application of this nanotechnology, particularly for a drug with ACDLog P in the range of ∼2-9. This study was aimed at elucidating the costabilizing role of cholesterol (CLT) in the FNP of AS-stabilized nanoparticles of itraconazole (ITZ), a model drug with an ACDLog P of 4.35 ± 1.22 and log P of 5.66. The presence of CLT was shown to reduce the initial particle size and markedly improve the short-term storage stability of ITZ nanoparticles. The stability-enhancement by CLT can be linked to its higher miscibility or stronger interaction with the AS hydrophobic moiety than with ITZ (as reflected by the absolute differences of their solubility parameter values). Surface analyses employing X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) suggest that, through the coprecipitation of CLT with ITZ to form a mixed hydrophobic drug core, the CLT molecules that are exposed on the core surface serve to afford a stronger and more timely surface anchorage of the AS hydrophobic moieties, thereby facilitating the rearrangement of AS molecules toward the stable micelle-like structure. The present findings offer a mechanistic insight into the interplay between amphiphilic stabilizer and costabilizer in enhancing the physical stability of drug nanoparticles and may carry important implications for the development of more stable and efficacious nanoparticle therapeutics.


Asunto(s)
Colesterol/química , Itraconazol/química , Nanopartículas/química , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía de Fuerza Atómica , Espectroscopía de Fotoelectrones , Solubilidad
6.
Surgeon ; 17(1): 19-27, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29880431

RESUMEN

BACKGROUND AND PURPOSE: There is limited literature discussing the residual nasolabial deformity of adult patients prior to undergoing orthognathic surgery. The purpose of this study is to determine the site and severity of the residual nasolabial soft tissue deformity between adult unilateral cleft lip and palate (UCLP) patients and a non-cleft reference group, prior to orthognathic surgery. MATERIAL AND METHODS: Sixteen adult male UCLP patients, who all received primary lip and palate surgery according to a standardised Hong Kong protocol were recruited for this study. Facial images of each individual were captured using three-dimensional (3D) stereophotogrammetry and compared to a previous published Hong Kong non-cleft reference group of 48 male adults. Using two-sample t-tests differences in linear and angular measurements and asymmetry scores were evaluated between the two groups. In addition a "conformed" average UCLP facial template was superimposed and compared to conformed average non-cleft reference group facial template. Reproducibility of the measurements were assessed using Students paired t-tests and coefficients of reliability. MAIN FINDINGS: Significant differences in linear and angular measurements and asymmetry scores were observed between the two groups (p < 0.05). Adult UCLP patients showed significantly narrower nostril floor widths, longer columella length on the unaffected side, a wider nose, shorter cutaneous lip height, shorter upper lip length and shorter philtrum length. Prior to orthognathic surgery adult UCLP patients showed significantly more facial asymmetry. Superimposition of the average facial meshes clearly showed the site and severity of the deficiency in the x, y and z-directions. CONCLUSIONS: Many of the nasolabial characteristics reported to be present in children following primary UCLP repair continue into adulthood. The detrimental soft tissue effects of orthognathic surgery for UCLP patients may be different to non-cleft individuals; and as such the site and severity of the residual deformity should be assessed prior to surgery.


Asunto(s)
Labio Leporino/cirugía , Fisura del Paladar/cirugía , Cara/diagnóstico por imagen , Asimetría Facial/diagnóstico por imagen , Surco Nasolabial/diagnóstico por imagen , Fotogrametría , Adolescente , Cara/anomalías , Cara/anatomía & histología , Cara/cirugía , Humanos , Imagenología Tridimensional , Masculino , Surco Nasolabial/anomalías , Surco Nasolabial/cirugía , Procedimientos Quirúrgicos Ortognáticos/métodos , Procedimientos de Cirugía Plástica , Adulto Joven
7.
Small ; 13(48)2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29125716

RESUMEN

Silicon doped tin oxide embedded porous carbon microspheres (Siy Sn1-y Ox @C) are synthesized. It is found that the doped Si not only improves the reversibility of lithiation/delithiation reactions, but also prevents Sn from aggregation. In addition, the doped Si introduces extra defects into the carbon matrix and produces Li+ conductive Li4 SiO4 , which accelerates Li+ diffusion. Together with the conductive, porous carbon matrix that provides void space to accommodate the volume change of Sn during charge/discharge cycling, the novel Siy Sn1-y Ox @C exhibits excellent electrochemical performance. It shows a high initial columbic efficiency of 75.9%. A charge (delithiation) capacity of 880.32 mA h g-1 is retained after 150 cycles, i.e., 91% of the initial capacity. These results indicate that the as-synthesized Siy Sn1-y Ox @C is a promising anode material for lithium ion batteries.

8.
Thromb Res ; 233: 138-144, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38043393

RESUMEN

INTRODUCTION: Acquired hemophilia A (AHA) is a rare bleeding disorder with destruction of factor VIII by autoantibodies. Comprehensive data for Chinese patients are lacking. Predictors of hospital stay have not been investigated. METHODS: A territory-wide review of patients diagnosed with AHA from January 1, 2012, to December 31, 2021 was performed by retrieving patients' information from an electronic database system in Hong Kong. RESULTS: Overall, 165 patients were included in this 10-year study, and the estimated incidence was 2.4 per million/year, which was higher than those reported from Caucasian cohorts. The median age of diagnosis was 80 years old. Patients had a long hospital stay (median: 25 days) and high mortality (55.2 %). The majority of deaths were caused by immunosuppression-related sepsis (49.5 %). Age was an independent predictor of overall survival (Hazard ratio: 1.065, 95 % CI: 1.037-1.093, p < 0.001), complete remission (CR) status (odd ratios (OR): 0.948, 95 % CI: 0.921-0.976, p < 0.001) and time to achieve CR (OR: 1.043, 95 % CI: 1.019-1.067, p < 0.001). Higher hemoglobin level on presentation was associated with shorter time to achieve CR (OR: 0.888, 95 % CI: 0.795-0.993, p = 0.037). Factor VIII level < 1 % normal, high inhibitor titer and intensive immunosuppressive regimen predicted long hospital stay. CONCLUSION: We presented comprehensive data of Chinese patients with AHA which comprised predominantly frail elderly who required long hospital stay and had high sepsis-related mortality. This posed challenges in managing AHA in such patients. Individualized immunosuppressive therapy is needed to balance the benefits and risk of septic complications.


Asunto(s)
Hemofilia A , Sepsis , Humanos , Anciano , Anciano de 80 o más Años , Hemofilia A/epidemiología , Hemofilia A/diagnóstico , Factor VIII , Estudios de Cohortes , Hong Kong/epidemiología , Respuesta Patológica Completa , Sepsis/complicaciones
9.
Matrix Biol ; 121: 127-148, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37348683

RESUMEN

Osteogenesis Imperfecta (OI) is a heritable collagen-related bone dysplasia characterized by bone fractures, growth deficiency and skeletal deformity. Type XIV OI is a recessive OI form caused by null mutations in TMEM38B, which encodes the ER membrane intracellular cation channel TRIC-B. Previously, we showed that absence of TMEM38B alters calcium flux in the ER of OI patient osteoblasts and fibroblasts, which further disrupts collagen synthesis and secretion. How the absence of TMEM38B affects osteoblast function is still poorly understood. Here we further investigated the role of TMEM38B in human osteoblast differentiation and mineralization. TMEM38B-null osteoblasts showed altered expression of osteoblast marker genes and decreased mineralization. RNA-Seq analysis revealed that cell-cell adhesion was one of the most downregulated pathways in TMEM38B-null osteoblasts, with further validation by real-time PCR and Western blot. Gap and tight junction proteins were also decreased by TRIC-B absence, both in patient osteoblasts and in calvarial osteoblasts of Tmem38b-null mice. Disrupted cell adhesion decreased mutant cell proliferation and cell cycle progression. An important novel finding was that TMEM38B-null osteoblasts had elongated mitochondria with altered fusion and fission markers, MFN2 and DRP1. In addition, TMEM38B-null osteoblasts exhibited a significant increase in superoxide production in mitochondria, further supporting mitochondrial dysfunction. Together these results emphasize the novel role of TMEM38B/TRIC-B in osteoblast differentiation, affecting cell-cell adhesion processes, gap and tight junction, proliferation, cell cycle, and mitochondrial function.


Asunto(s)
Osteogénesis Imperfecta , Animales , Humanos , Ratones , Adhesión Celular , Colágeno/metabolismo , Canales Iónicos/genética , Canales Iónicos/metabolismo , Multiómica , Osteoblastos , Osteogénesis/genética , Osteogénesis Imperfecta/genética , Osteogénesis Imperfecta/metabolismo
10.
Rev Sci Instrum ; 93(7): 073501, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35922317

RESUMEN

We present a novel approach to reconstruct three-dimensional (3D) electron temperature distributions of inertially confined fusion plasma hotspots at the National Ignition Facility. Using very limited number of two-dimensional (2D) x-ray imaging lines of sight, we perform 3D reconstructions of x-ray emission distributions from different x-ray energy channels ranging from 20 to 30 keV. 2D time-integrated x-ray images are processed using the algebraic reconstruction technique to reconstruct a 3D hotspot x-ray emission distribution that is self-consistent with the input images. 3D electron temperatures are computed using the energy channel ratios. We demonstrate the high accuracy and applicability of this method with different complex hotspot geometries in both synthetic and experimental results.

11.
Polymers (Basel) ; 14(20)2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36297907

RESUMEN

A novel calcium copper titanate (CaCu3Ti4O12)-polyvinylidene fluoride composite (CCTO@PVDF) with Cu-deficiency was successfully prepared through the molten salt-assisted method. The morphology and structure of polymer composites uniformly incorporated with CCTO nanocrystals were characterized. At the same volume fraction, the CCTOs with Cu-deficiency displayed higher dielectric constants than those without post-treatment. A relatively high dielectric constant of 939 was obtained at 64% vol% CCTO@PVDF content, 78 times that of pure PVDF. The high dielectric constants of these composites were attributed to the homogeneous dispersion and interfacial polarization of the CCTO into the PVDF matrix. These composites also have prospective applications in high-frequency regions (106 Hz). The enhancement of the dielectric constant was predicted in several theoretical models, among which the EMT and Yamada models agreed well with the experimental results, indicating the excellent distribution in the polymer matrix.

12.
Chemistry ; 17(27): 7694-700, 2011 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-21563220

RESUMEN

By a simple and facile wet-chemistry technique without any surfactant, various shapes of Ag(2)S crystals--including leaflike pentagonal nanoplates, crinkly nanoscrolls, hexagonal prismlike microtubes, and microrods--were fabricated in situ on a large-area silver-foil surface separately. Detailed experiments revealed that the Ag(2)S nanoplates were formed just by immersing the silver foil in a sulfur/ethanol solution at room temperature and atmospheric pressure, and they subsequently rolled into nanoscrolls and further grew into microtubes and microrods under solvothermal conditions. Inspired by the natural curling of a piece of foliage, we proposed a surfactant-free rolling mechanism to interpret the observed morphological evolution from lamellar to tubular structures. Based on these simple, practical, and green chemical synthetic routes, we can easily synthesize lamellar, scrolled, tubular, and clubbed Ag(2)S crystals by simply adjusting the reaction temperature, pressure, and time. It is very interesting to note that the current rolling process is quite different from the previous reported rolling mechanism that highly depends on the surfactants; we revealed that the lamellar Ag(2)S could be rolled into tubular structures without using any surfactant or other chemical additives, just like the natural rolling process of a piece of foliage. Therefore, this morphology-controlled synthetic route of Ag(2)S crystals may provide new insight into the synthesis of metal sulfide semiconducting micro-/nanocrystals with desired morphologies for further industrial applications. The optical properties of the pentagonal Ag(2)S nanoplates/film were also investigated by UV/Vis and photoluminescence (PL) techniques, which showed large blue-shift of the corresponding UV/Vis and PL spectra.


Asunto(s)
Membranas Artificiales , Microtúbulos/química , Nanoestructuras/química , Compuestos de Plata/química , Tamaño de la Partícula , Propiedades de Superficie
13.
ACS Appl Mater Interfaces ; 13(29): 34134-34144, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34260193

RESUMEN

Although sodium-ion batteries (SIBs) have high potential for applications in large-scale energy storage, their limited cycle life and unsatisfactory energy density hinder their commercial applications. Here, a superior stable CoTe2/carbon anode, in which CoTe2 nanoparticles are embedded in freestanding N-doped multichannel carbon fiber (CoTe2@NMCNFs), with ultralong cycle life for SIBs, is reported. Specifically, CoTe2 nanoparticles are uniformly dispersed in the carbon matrix to inhibit its volume expansion and agglomeration during the desodiation/sodiation process, enabling a high-capacity and stable energy storage (retains 204.3 mAh g-1/612.9 mAh cm-3 at 1 A g-1 after 2000 cycles with an ultralow capacity decay of 0.016% per cycle). Moreover, a CoTe2@NMCNFs electrode exhibits a pseudocapacitive-dominated behavior, enabling the high-rate performance (152.4 mAh g-1/457.2 mAh cm-3 at 10 A g-1). The battery-capacitive dual-model reaction mechanism and outstanding reversibility of the CoTe2@NMCNFs composite are systematically investigated by ex situ XRD/SEM/TEM and a galvanostatic intermittent titration technique test, as well as surface capacitance calculations. More importantly, the fabricated sodium-ion CoTe2@NMCNFs//P2-NaNMMT-4 full cell delivers a stable reversible capacity of 445 Wh kg-1anode at 0.2 A g-1 and an excellent rate performance. The facile synthetic approach together with unique nanostructural design, provides a meaningful reference for the rational design of next-generation ultralong cycle-life SIBs anodes.

14.
Oral Health Prev Dent ; 19(1): 203-216, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33723980

RESUMEN

PURPOSE: To evaluate the comprehensive effects of photobiomodulation (PBM) therapy on teeth after active orthodontic treatment. MATERIALS AND METHODS: This systematic review was conducted according to the PRISMA guidelines. Six databases were electronically searched and screened for eligible human and animal studies published up to August 2020. The risk of bias was assessed based on the Cochrane Handbook for Systematic Reviews of Interventions and Systematic Review Centre for Laboratory Experiment Tool. Two independent reviewers performed all procedures in duplicate. Any disagreement was resolved by discussion or consultation with a third reviewer. RESULTS: A total of 395 records were identified from the initial search up to August 2020. Following screening, 16 full-text articles were reviewed for eligibility (κ > 0.90), and ultimately 9 studies (3 clinical studies and 6 animal studies) were included in this review. The key outcomes observed were 'tooth position maintenance' and 'root resorption rehabilitation'. Two controlled clinical trials and two animal studies supported the preventive effects of PBM therapy on the relapse of post-orthodontic tooth positions, while the other two animal studies reported opposing findings. Regarding root resorption, all evidence supported the rehabilitation potential using PBM therapy for teeth that had undergone orthodontic tooth movement. There was a high risk of bias among studies, except for one randomised controlled trial. Due to the substantial heterogeneity among studies in terms of their types, participants, designs, PBM therapy settings and variables of interest, it was not possible to conduct a meta-analysis; therefore, a qualitative synthesis is presented. CONCLUSION: The quality of evidence for PBM therapy contributing to the maintenance of tooth position or improved dental health after orthodontic treatment remains low. There is considerable controversy over the effects of PBM therapy on orthodontic relapse. However, the use of PBM therapy after orthodontic treatment has promising effects for root resorption rehabilitation and is generally recommended.


Asunto(s)
Terapia por Luz de Baja Intensidad , Resorción Radicular , Animales , Atención Odontológica , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Técnicas de Movimiento Dental
15.
Int J Pharm ; 598: 120224, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33486028

RESUMEN

Ibuprofen (IBP), a common non-steroidal anti-inflammatory drug (NSAID) with a log P of 3.51, has been shown to possess potential benefit in the treatment of Alzheimer's disease. However, the bioavailability of IBP to the brain is poor, which can be linked to its extensive binding to plasma proteins in the blood. This study aimed to evaluate the nanoparticle production of IBP by flash nanoprecipitation (FNP) technology, and to determine whether the nanoparticles prepared by FNP could enhance the delivery of IBP into the brain. Polymeric IBP nanoparticles were prepared with poly(ethylene glycol)-poly(lactic acid) (PEG-PLA) diblock copolymer as stabilizer under optimized conditions using a four-stream multi-inlet vortex mixer (MIVM). The optimized nanoparticles displayed a mean particle size of around 50 nm, polydispersity index of around 0.2, drug loading of up to 30% and physical stability of up to 34 days. In-depth surface characterization using zeta potential measurement, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) showed that the surfaces of these nanoparticles were covered with the hydrophilic PEG groups from the diblock copolymer. In vivo brain uptake study of the IBP nanoparticles indicated that the particles, when coated with polysorbate 80, displayed an enhanced brain uptake. However, the extent of brain uptake enhancement appeared limited, possibly due to a rapid release of IBP from the nanoparticles into the blood stream following intravenous administration.


Asunto(s)
Ibuprofeno , Nanopartículas , Encéfalo , Tamaño de la Partícula , Polietilenglicoles , Polímeros
16.
Talanta ; 191: 241-247, 2019 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-30262057

RESUMEN

Here, we report a dual-use surface-enhanced Raman scattering (SERS) substrate based on a flexible three-dimensional (3D) chitosan foam, onto which silver nanoparticles (Ag NPs) are firmly immobilized through amino groups from chitosan chains. The SERS substrate can actively collect analytes either on solid surface by swabbing or in solution by adsorption. The compressible characteristic of chitosan foam enables easy removal of solvent through gentle pressing, which can achieve fast pre-concentrating of analytes before measurements. In addition, the substrate is shape adaptable and thus is suitable for sampling contaminants on solid surfaces. The SERS substrates exhibit acceptable reproducibility (16.4% in relative standard deviation). Furthermore, it detects Raman probe Nile Blue A down to 5 pg by swabbing solid surface and Rhodamine 6G down to 10 ppb by adsorbing analyte in the solution. Three pesticide samples (triazophos, methidathion, and isocarbophos) can also be detected down to µg level with the substrate. It is believed that such a versatile SERS substrate may find great opportunity in realistic sensing applications.

17.
Oral Health Prev Dent ; 6(2): 105-18, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18637388

RESUMEN

PURPOSE: To study oral health conditions, diabetic medical complications and their association in type 2 diabetes mellitus (DM). MATERIALS AND METHODS: Cross-sectional survey of 364 type 2 DM patients (63.6 +/- 10.1 years, 54% female) and 161 controls (64.1 +/- 10.6 years, 53% female) with or without essential hypertension, predominantly low-income, attending a hospital were recruited. Periodontal disease (Community Periodontal Index [CPI]) and dental status (decayed, missing and filled teeth [DMFT]) were recorded. Fasting plasma glucose and, for DM patients, HbA1C and DM complications were recorded on enrolment and follow up, respectively. RESULTS: Many DM subjects had fair diabetic control. Both groups (control/DM) had poor oral health: DMFT = 14.5/16.8, CPI 4 = 36%/50%, (P < 0.02) while DM subjects had less DT(adjusted) = 2.1/1.4 (P < 0.01). Of the follow-up DM individuals, 294 (81%) had medical complication(s). Regression analyses showed association between advanced periodontal attachment loss (ALoss) and age, male gender, smoking and DM; MT and DMFT were associated with age, female gender, smoking, DM and hypertension. ALoss and DMFT were not associated with DM complications. CONCLUSIONS: The oral health of the surveyed Chinese subjects was poor. Type 2 DM subjects were affected more by ALoss and MT but less DT. Subjects with hypertension had higher odds for MT.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Estado de Salud , Salud Bucal , Pobreza , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Glucemia/análisis , China/etnología , Estudios Transversales , Índice CPO , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Hong Kong , Humanos , Hipertensión/complicaciones , Masculino , Persona de Mediana Edad , Pérdida de la Inserción Periodontal/complicaciones , Índice Periodontal , Periodontitis/complicaciones , Estudios Prospectivos , Factores de Riesgo , Factores Sexuales
18.
Int J Pharm ; 542(1-2): 221-231, 2018 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-29555440

RESUMEN

Flash nanoprecipitation (FNP) is a controlled antisolvent precipitation process that has proven effective for consistent production of drug nanoparticles with a defined mean particle size and narrow particle size distribution. However, physical instability of the generated nanoparticles remains a major challenge in the application of this technology in pharmaceutical formulation. Aimed at resolving this problem, the present study has investigated the FNP process and associated stabilization mechanism of itraconazole (ITZ) nanoparticles through in-depth nanoparticle characterization. Results showed that ITZ nanoparticles could be reproducibly produced with a mean particle size <100 nm and a polydispersity index <0.2 in the presence of amphiphilic stabilizers (ASs). Surface analysis of freshly formed nanoparticles by X-ray photoelectron spectroscopy (XPS) revealed initially a disordered packing structure and subsequently a time-dependent molecular rearrangement of incorporated AS towards a micelle-like structure. The faster the molecular rearrangement of AS, the more stable the nanoparticles, as monitored by the change in particle size with time. These findings may have important implications for the selection of effective ASs for formulating stable drug nanoparticles. The present study is the first of its kind to demonstrate the utility of XPS to track the molecular transport of stabilizers in rapidly generated nanoparticles.


Asunto(s)
Antifúngicos/química , Itraconazol/química , Nanopartículas/química , Precipitación Química , Composición de Medicamentos , Estabilidad de Medicamentos , Microscopía de Fuerza Atómica , Espectroscopía de Fotoelectrones , Polietilenglicoles/química , Vitamina E/química
19.
BMC Res Notes ; 11(1): 709, 2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-30309382

RESUMEN

OBJECTIVE: An observational post-randomized controlled trial (RCT) design was adopted to evaluate the long-term sustainability and maintenance of improved glycemic control, lipid profile, reduced progression to diabetes at 3-year following a 2-year short messaging service (SMS). We performed a naturalistic follow-up to the 104 participants of SMS intervention, a 2-year randomized controlled trial comparing the SMS to non-SMS for pre-diabetes. All participants were arranged screening for diabetes at 5-year assessment. Primary outcome of this post-RCT study was cumulative incidence of diabetes whereas secondary outcomes were the change in biometric data over a 5-year period. RESULTS: After a mean 57-month follow-up, 19 (18.3%) were lost to follow-up after the RCT period. Progression to diabetes occurred in 20 and 16 patients among the intervention and control group respectively, with no significant between-group difference (8.06 and 7.31 cases per 100 person years, respectively; Hazard Ratio in the intervention group, 1.184; 95% confidence interval, 0.612 to 2.288; p-value = 0.616). No significant effect of SMS on reduction in diabetes was observed in overall and pre-defined subgroups. The SMS intervention preserved the clinical benefits within the trial period but failed to transform from treatment efficacy to long-term effectiveness beyond 2 years after intervention. Trail registration ClinicalTrials.gov Identifier NCT01556880, retrospectively registered on March 16, 2012.


Asunto(s)
Estado Prediabético/prevención & control , Sistemas Recordatorios , Conducta de Reducción del Riesgo , Envío de Mensajes de Texto , Anciano , Glucemia/metabolismo , Presión Sanguínea/fisiología , Índice de Masa Corporal , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Prediabético/sangre , Estado Prediabético/fisiopatología , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Triglicéridos/sangre
20.
Nanoscale ; 9(48): 19408-19414, 2017 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-29210425

RESUMEN

Iron sulfide embedded porous carbon hollow spheres (FeSx@CS) have been successfully synthesized through a facile and environment friendly in situ synthetic method. Using this method, a porous carbon matrix and uniformly dispersed iron sulfide nanoparticles were formed simultaneously and assembled into hollow spheres. The as-synthesized FeSx@CS material showed high reversible capacity, outstanding cycle performance, and excellent rate capability when it was applied as an anode material for sodium ion batteries. It delivered a remarkable charge capacity of 656.75 mA h g-1 in the first cycle and a capacity retention of 97% after 100 cycles. When the current density was increased from 50 mA g-1 to 1000 and 2000 mA g-1, high capacity retention of 76.3% and 62.5% was achieved, respectively.

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