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1.
Retina ; 44(3): 527-536, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37972986

RESUMO

PURPOSE: To investigate fundus tessellation density (TD) and its association with axial length (AL) elongation and spherical equivalent (SE) progression in children. METHODS: The school-based prospective cohort study enrolled 1,997 individuals aged 7 to 9 years in 11 elementary schools in Mojiang, China. Cycloplegic refraction and biometry were performed at baseline and 4-year visits. The baseline fundus photographs were taken, and TD, defined as the percentage of exposed choroidal vessel area in the photographs, was quantified using an artificial intelligence-assisted semiautomatic labeling approach. After the exclusion of 330 ineligible participants because of loss to follow-up or ineligible fundus photographs, logistic models were used to assess the association of TD with rapid AL elongation (>0.36 mm/year) and SE progression (>1.00 D/year). RESULTS: The prevalence of tessellation was 477 of 1,667 (28.6%) and mean TD was 0.008 ± 0.019. The mean AL elongation and SE progression in 4 years were 0.90 ± 0.58 mm and -1.09 ± 1.25 D. Higher TD was associated with longer baseline AL (ß, 0.030; 95% confidence interval: 0.015-0.046; P < 0.001) and more myopic baseline SE (ß, -0.017; 95% confidence interval: -0.032 to -0.002; P = 0.029). Higher TD was associated with rapid AL elongation (odds ratio, 1.128; 95% confidence interval: 1.055-1.207; P < 0.001) and SE progression (odds ratio, 1.123; 95% confidence interval: 1.020-1.237; P = 0.018). CONCLUSION: Tessellation density is a potential indicator of rapid AL elongation and refractive progression in children. TD measurement could be a routine to monitor AL elongation.


Assuntos
Inteligência Artificial , Miopia , Criança , Humanos , Estudos Prospectivos , Refração Ocular , Testes Visuais , Miopia/diagnóstico , Miopia/epidemiologia , Comprimento Axial do Olho
2.
Luminescence ; 35(6): 877-884, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32150663

RESUMO

A simple and ultrasensitive flow injection chemiluminescence competitive immunoassay based on gold nanoparticle-loaded enzyme for the detection of chloramphenicol (CAP) residues in shrimp and honey has been developed. Due to their good biocompatibility and large specific surface area, carboxylic resin beads can be used as solid phase carriers to immobilize more coating antigens (Ag). In addition, gold nanoparticles could provide an effective matrix for loading more CAP antibody and horseradish peroxidase, which would effectively catalyze the system of luminol-p-iodophenol (PIP)-H2 O2 . A competitive immunoassay strategy was used for detection of CAP, in which CAP in the sample would compete with the coating Ag for the limited antibodies, leading to a chemiluminescence (CL) signal decrease with increase in CAP concentration. A wide linear range 0.001-10 ng ml-1 (R2 = 0.9961) was obtained under optimized conditions, and the detection limit (3σ) was calculated to be 0.33 pg ml-1 . This method was also been successfully applied to determine CAP in shrimp and honey samples. The immunosensor proposed in this study not only has the advantages of high sensitivity, wider linear range, and satisfactory stability, but also expands the application of flow injection CL immunoassay in antibiotic detection.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Cloranfenicol , Ouro , Imunoensaio , Limite de Detecção , Luminescência , Medições Luminescentes
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 986-9, 2014 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25007614

RESUMO

Nano-silver colloid was synthesized by using microwave method on the mixtures of sodium citrate solution and silver nitrate solution. The method has advantages of fast heating speed, uniform temperature distribution and easily controlled reaction conditions. The sizes and size distributions of the silver particles were characterized by means of quasi-elastic laser scattering (QLS). The average particles size was (53.27 +/- 2.65) nm and the size of the particles was mainly distributed around 56 nm. Surface-enhanced Raman spectra of the degradation products from goat horn were obtained with silver colloid as active substrate. It was observed that the Raman signal of SERS was enhanced significantly compared with that of regular Raman spectrum, especially at the Raman bands of 659, 830, 850, 929, 999, 1 028, 1 280, 1 439 and 1 599 cm(-1) which reflect the biochemical components in degradation products. The characteristic Raman bands of degradation products from goat horn were preliminary assigned. The assignments showed that the main constituents of the degradation products from goat horn were amino acids and polypeptides. It was for the first time that Surface-enhanced Raman spectroscopy was used to detect trace degradation products from the horns. Raman signal enhancement can be obtained with high sensitivity for the trace concentrations as low as ppm level. It is concluded that surface-enhanced Raman spectroscopy can provide a fast, direct and precise detecting method for the detection of trace degradation solution from horns.


Assuntos
Cabras , Cornos/química , Análise Espectral Raman , Animais , Coloides , Nanopartículas Metálicas , Micro-Ondas , Tamanho da Partícula , Prata
4.
Water Res ; 258: 121773, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38796910

RESUMO

Sulfite (S(IV)), as an alternative to persulfate, has demonstrated its cost-effectiveness and environmentally friendly nature, garnering increasing attention in Advanced Oxidation Processes (AOPs). Dissolved organic matter (DOM) commonly occurred in diverse environments and was often regarded as an interfering factor in sulfite-based AOPs. However, less attention has been paid to the promotion of the activation of sulfite by excited DOM, which could produce various reactive intermediates. The study focused on the activation of sulfite using visible light (VL) - excited humic acid (HA) to efficiently degrade many common organic pollutants, which was better than peroxydisulfate (PDS) and peroxymonosulfate (PMS) systems. Quenching experiments and electron paramagnetic resonance (EPR) analysis revealed that the triplet states of HA (3HA*) activated sulfite through energy transfer, resulting in the production of SO4·-, O2·-, and 1O2. The most significant active species found in the degradation of roxarsone (ROX) was 1O2, which was a non-radical pathway and exhibits high selectivity for pollutant degradation. This non-radical pathway was not commonly observed in traditional sulfite-based AOPs. Additionally, the coexistence of various inorganic anions, such as NO3-, Cl-, SO42-, CO32-, and PO43-, had little effect on the degradation of ROX. Furthermore, DOM from different natural water demonstrated efficient activation of S(IV) under light conditions, opening up new possibilities for applying sulfite-based advanced oxidation to the remediation of organic pollution in diverse sites and water bodies. In summary, this research offered promising insights into the potential application of sulfite-based AOPs, facilitated by photo-excited HA, as a new strategy for efficiently degrading organic pollutants in various environmental settings.


Assuntos
Substâncias Húmicas , Luz , Sulfitos , Águas Residuárias , Poluentes Químicos da Água , Sulfitos/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Eliminação de Resíduos Líquidos/métodos , Oxirredução
5.
Sci Total Environ ; 921: 171052, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38373459

RESUMO

Listening to natural sounds, both live and recorded, in either a natural or built environment is considered natural sound exposure (NSE). Sound is closely related to daily life, and research on the restorative effects of natural sounds is expanding. However, there is a lack of quantitative and comprehensive analysis on the impact of NSE on health recovery. This study systematically reviewed and conducted a meta-analysis on the impact of NSE on health recovery. Fifteen studies (1285 participants) were selected for the meta-analysis out of the 1157 literatures about the recovery of the NSE, searched from the Web of Science and Science Direct. The results indicate that NSE has certain positive effects: (a) In terms of emotional changes, NSE significantly reduces anxiety as measured by both the Visual Analog Scale (VAS) -2.31 (95 % CI -2.83, -1.79) and the State Anxiety Inventory (SAI) -12.22 (95 % CI -22.46, -1.98). (b) In terms of physiological reaction, NSE resulted in reduced heart rate (HR) -5.46 (95 % CI -9.62, -1.31), systolic blood pressure (SBP) -11.74 (95 % CI -15.51, -7.97), diastolic blood pressure (DBP) -13.98 (95 % CI -24.96, -2.99) and respiratory rate (RR) -1.58 (95 % CI -3.06, -0.10). (c) While the potential for restoration of cognitive performance by NSE was found, no consistent conclusions have been reached yet. However, there was significant heterogeneity between studies, primarily attributed to variations in study populations and methodologies. Because of the limited literature, we did not conduct subgroup analysis and meta-regression analysis. It is recommended that future studies address this heterogeneity by including more and higher-quality literature and employing rigorous methodologies to establish a robust foundation for evidence-based medicine. This will be of great significance for the application natural sounds in landscape planning and medical rehabilitation environments, and has the potential to promote improvements in public health.


Assuntos
Ansiedade , Emoções , Som , Humanos , Saúde Pública
6.
Sci Rep ; 8(1): 10182, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29976982

RESUMO

Despite involvement of melatonin (MT) in plant growth and stress tolerance, its role in sulfur (S) acquisition and assimilation remains unclear. Here we report that low-S conditions cause serious growth inhibition by reducing chlorophyll content, photosynthesis and biomass accumulation. S deficiency evoked oxidative stress leading to the cell structural alterations and DNA damage. In contrast, MT supplementation to the S-deprived plants resulted in a significant diminution in reactive oxygen species (ROS) accumulation, thereby mitigating S deficiency-induced damages to cellular macromolecules and ultrastructures. Moreover, MT promoted S uptake and assimilation by regulating the expression of genes encoding enzymes involved in S transport and metabolism. MT also protected cells from ROS-induced damage by regulating 2-cysteine peroxiredoxin and biosynthesis of S-compounds. These results provide strong evidence that MT can enhance plant tolerance to low-S-induced stress by improving S uptake, metabolism and redox homeostasis, and thus advocating beneficial effects of MT on increasing the sulfur utilization efficiency.


Assuntos
Homeostase/efeitos dos fármacos , Melatonina/administração & dosagem , Solanum lycopersicum/fisiologia , Estresse Fisiológico/efeitos dos fármacos , Enxofre/deficiência , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Peroxirredoxinas/metabolismo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Solo/química
7.
Biosens Bioelectron ; 101: 66-74, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29040916

RESUMO

We report here a versatile on-stage microfluidic cell culture and assay system which is compatible with different microscopes and sensors, can simultaneously perform steps of long term cell culture, high throughput time lapse cell assays/imaging, and cell micromanipulations. With the system, we cultured a variety of cells for different periods of time and monitored their cell morphology, migration and division. We also performed a series non-invasive real time in situ time lapse assays and micromanipulations on different cells. They include: the first time lapse imaging and measurements on the instantaneous variations of morphology, biomechanical properties and the intracellular protein of human red blood cells in responding to pH fluctuation, drug action and electromagnetic radiation; the first continuous time lapse Raman micro-spectroscopy on a CHO cell in different phases of its entire life cycles; the micro-transfection of GFP into B16 cells and the follow up observation of the cell's morphology and expressed GFP fluorescence varying with incubation time and cell generations. The performance of these experiments not only demonstrated the capability of the system, but also proposed a variety of novel methods for obtaining time- and spatially-resolved information about the cellular and molecular heterogeneity and transformation during development or stimulations.


Assuntos
Técnicas de Cultura de Células/instrumentação , Dispositivos Lab-On-A-Chip , Micromanipulação/instrumentação , Imagem com Lapso de Tempo/instrumentação , Animais , Técnicas Biossensoriais/instrumentação , Células CHO , Divisão Celular , Linhagem Celular , Movimento Celular , Proliferação de Células , Cricetulus , Desenho de Equipamento , Eritrócitos/citologia , Células Endoteliais da Veia Umbilical Humana , Humanos
8.
Exp Ther Med ; 12(5): 3476-3484, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27882182

RESUMO

The majority of patients with hepatitis C virus (HCV) in China were infected via blood transfusion prior to the year 1996. In this systematic retrospective cohort study, disease progression in 804 consecutive patients with transfusion-acquired HCV is investigated. In addition, the occurrence of compensated cirrhosis, decompensated cirrhosis and hepatocellular carcinoma (HCC) is analyzed among these patients, along with the risk factors for disease progression. Patients with cirrhosis or HCC were classified as the serious development group (SD group) and the remaining patients with chronic hepatitis were classified as the hepatitis group (H group). Significant differences were found between the two groups in age at the time of infection, duration of infection and age at the time of observation. SD group patients were significantly older at the time of transfusion (33.73 vs. 23.56 years; P<0.001), with a significantly longer mean duration of HCV infection (21.88 vs. 21.15 years; P=0.029) compared with that in the H group. Male gender and age at the time of transfusion were significant risk factors for HCC (OR=2.48, P=0.031 and OR=1.07, P=0.002, respectively). Age was a significant risk factor for disease progression in older Chinese patients with transfusion-acquired HCV, and there were significant differences in the prevalence of compensated cirrhosis, decompensated cirrhosis and HCC between the age groups (P<0.001), suggesting that more patients with HCV may develop cirrhosis or HCC in their third and fourth decades of infection. Results of the present study will be helpful for predicting disease progression in Chinese patients with HCV infected via blood transfusion.

9.
Mater Sci Eng C Mater Biol Appl ; 33(8): 5036-43, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24094221

RESUMO

The microstructure and mechanical properties of horns derived from three domestic bovines (buffalo, cattle and sheep) were examined. The effects of water content, sampling position and orientation of three bovid horns on mechanical properties were systematically investigated by uniaxial tension and micron indentation tests. Meanwhile, the material composition and metal element contents were determined by Raman spectroscopy and elemental analysis respectively, and the microstructures of the horns were measured by scanning electron microscopy (SEM). Results show that the mechanical properties of horns have negative correlation with water contents and depend on sampling position and orientation. The spatial variations of the mechanical properties in horns are attributed to the different keratinization degrees in the proximal, middle and distal parts. And the mechanical properties of horns in the longitudinal direction are better than those in transverse. Among the three kinds of horns, the mechanical properties of buffalo horn are the best, followed by cattle horn, and those in sheep horn are the worst. This is due to the differences in material composition, metal element, and the microstructures of the horns. But the mechanical properties of buffalo horns are not dependent on the source of the buffalo. Therefore, regular engineered buffalo keratinous materials with standard mechanical properties can be obtained from different buffalo horns by using proper preparation methods.


Assuntos
Cornos/química , Animais , Búfalos , Bovinos , Força Compressiva , Módulo de Elasticidade , Dureza , Cornos/metabolismo , Queratinas/metabolismo , Microscopia Eletrônica de Varredura , Ovinos , Análise Espectral Raman , Resistência à Tração , Água/química
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