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1.
Artigo em Inglês | MEDLINE | ID: mdl-37490379

RESUMO

The 6-min walk distance (6MWD) and the Fugl-Meyer assessment lower-limb subscale (FMA-LE) of the stroke patients provide the critical evaluation standards for the effect of training and guidance of the training programs. However, gait assessment for stroke patients typically relies on manual observation and table scoring, which raises concerns about wasted manpower and subjective observation results. To address this issue, this paper proposes an intelligent rehabilitation assessment method (IRAM) for rehabilitation assessment of the stroke patients based on sensor data of the lower limb exoskeleton robot. Firstly, the feature parameters of the patient were collected, including age, height, and duration, etc. The sensor data of the exoskeleton robot were also collected, including joint angle, joint velocity, and joint torque, etc. Secondly, a gait feature model was constructed to deduce the walking gait parameters of the patient according to the sensor data of the exoskeleton, including the support phase to swing phase ratio, step length and leg lift height of the patient, etc. Then, the 6MWD and FMA-LE values were collected by traditional methods, feature parameters, gait parameters and human-machine interaction parameters (joint torque) of the patient were adopted to train the rehabilitation assessment model. Finally, the assessment model was trained by a machine-learning based algorithm. The new stroke patients' the 6MWD and FMA-LE values can be predicted by the trained model. The experimental results present that the prediction accuracy for the 6MWD and FMA-LE values reach to 85.19% and 92.66%, respectively.


Assuntos
Exoesqueleto Energizado , Robótica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/métodos , Marcha , Extremidade Inferior
2.
Quant Imaging Med Surg ; 13(2): 935-945, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36819274

RESUMO

Background: Dental implant failure is a critical condition that can seriously compromise therapeutic efficacy. Insufficient bone volume, unfavorable bone quality, periodontal bone loss, and systemic conditions, including osteopenia/osteoporosis and diabetes mellitus, have been associated with implant failure. Early indicators of potential implant failure could help mitigate the risk of severe complications. This study aimed to develop an effective implant outcome prediction model using dental periapical and panoramic films. Methods: A total of 248 patients (89 with failed implants and 159 with successful implants) were examined. A total of 529 periapical images and 551 panoramic images were collected from the patients for a deep learning-based model. Based on radiographic peri-implant alveolar bone pattern, implant outcome was divided into three categories: implant failure with marginal bone loss, implant failure without marginal bone loss, and implant success. We extracted features using a deep convolutional neural network (CNN) and built a hybrid model to combine periapical and panoramic images. A comparison among three categories of receiver operating characteristic (ROC) curves was performed. The diagnostic accuracy, precision, recall and F1-score of the dataset were assessed. Results: Our model achieved an AUC (area under the ROC curve) of 0.972 for failure with marginal bone loss, 0.947 for failure without marginal bone loss and 0.975 for success. In all conditions, for periapical images alone, the diagnostic accuracy was 78.6%; the precision was 0.84, recall was 0.73, and F1-score was 0.75. For panoramic images alone, the diagnostic accuracy was 78.7%; the precision was 0.87, recall was 0.63, and F1-score was 0.66. Both periapical and panoramic images were used in our novel method, and the prediction accuracy was 87%. The precision was 0.85, recall was 0.88, and F1-score was 0.85. Conclusions: The deep learning model used features from periapical and panoramic images to effectively predict the occurrence of implant failure and might facilitate early clinical intervention for potential dental implant failures.

3.
BMJ Open ; 12(6): e054881, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35725256

RESUMO

INTRODUCTION: Coronary artery disease (CAD) is the leading cause of death worldwide. More than a quarter of cardiovascular events are unexplained by current absolute cardiovascular disease risk calculators, and individuals without clinical risk factors have been shown to have worse outcomes. The 'anatomy of risk' hypothesis recognises that adverse anatomical features of coronary arteries enhance atherogenic haemodynamics, which in turn mediate the localisation and progression of plaques. We propose a new risk prediction method predicated on CT coronary angiography (CTCA) data and state-of-the-art machine learning methods based on a better understanding of anatomical risk for CAD. This may open new pathways in the early implementation of personalised preventive therapies in susceptible individuals as a potential key in addressing the growing burden of CAD. METHODS AND ANALYSIS: GeoCAD is a retrospective cohort study in 1000 adult patients who have undergone CTCA for investigation of suspected CAD. It is a proof-of-concept study to test the hypothesis that advanced image-derived patient-specific data can accurately predict long-term cardiovascular events. The objectives are to (1) profile CTCA images with respect to variations in anatomical shape and associated haemodynamic risk expressing, at least in part, an individual's CAD risk, (2) develop a machine-learning algorithm for the rapid assessment of anatomical risk directly from unprocessed CTCA images and (3) to build a novel CAD risk model combining traditional risk factors with these novel anatomical biomarkers to provide a higher accuracy CAD risk prediction tool. ETHICS AND DISSEMINATION: The study protocol has been approved by the St Vincent's Hospital Human Research Ethics Committee, Sydney-2020/ETH02127 and the NSW Population and Health Service Research Ethics Committee-2021/ETH00990. The project outcomes will be published in peer-reviewed and biomedical journals, scientific conferences and as a higher degree research thesis.


Assuntos
Doença da Artéria Coronariana , Adulto , Estudos de Coortes , Angiografia por Tomografia Computadorizada , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Humanos , Valor Preditivo dos Testes , Estudos Retrospectivos
4.
Water Res ; 210: 117980, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34974347

RESUMO

There are growing concerns over the contributions of biofilms to disinfection byproduct (DBP) formation in engineered water systems (EWSs). Three kinds of water supply pipes, ductile iron (DI), cement-lined stainless steel (SS) and polyethylene (PE) pipes, were selected for the experiment conducted in this study. Based on test results, the three pipe biofilms showed relatively obvious differences in growth, morphological characteristics, organic components and bacterial diversity. Secreted extracellular polymeric substance (EPS) accounted for more than 90% of the biofilm and had greater disinfection byproduct formation potential (DBPFP) than the cell phases. DI pipe wall biofilms had the highest DBPFP, which to a certain extent means that denser and richer organic matter can be produced as the precursor of different types of DBPs. UHPLC-Q Exactive was used to identify the types of DBPs generated from the chlorination of histidine (His), alanine (Ala) and tryptophan (Trp) shared by the three pipe materials and their formation pathways. Compared to carbonaceous disinfection by-products (C-DBPs), nitrogenous disinfection by-products (N-DBPs) had a significant advantage in toxicity generation potentials in the biofilms, especially dichloroacetonitrile (DCAN) and trichloronitromethane (TCNM). DCAN and haloacetic acids (HAAs) were the key to cytotoxicity in biofilms, while TCNM was dominant in biofilm genotoxicity.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Biofilmes , Desinfecção , Matriz Extracelular de Substâncias Poliméricas/química , Halogenação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Abastecimento de Água
5.
Chemosphere ; 289: 133218, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34890609

RESUMO

Pipe material and residual chlorine are key factors for the drinking water distribution system, and understanding the biofilm ecosystem is vital for water quality safeguard. The aim of our study was to determine the influence of pipe materials (ductile iron, steel, polyethylene) and chlorination on the biofilm structure and microbial community, as shown by the physicochemical properties, extracellular polymeric substances (EPS) structural characteristics, bacterial community composition, and functional traits. EPS spatial properties were studied based on a semi-quantitative confocal laser scanning microscope (CLSM) description. Regarding the impact of chlorination, residule chlorine (1.0 ± 0.3 mg L-1 free chlorine) could inhibit the bacteria colonization, and initiate a potential response to external disinfectants revealed by the EPS spatial distribution changes and communities variation compared to unchlorinated system. Regarding the impact of pipe material, polyethylene (PE) biofilms displayed lower biomass, loose zoogloea structure, lower proteins and polysaccharides content, and poor microbial diversity in contrast to ductile iron and steel biofilms. Pipe material was the more possible driving factor of the biofilm community composition compared to the chlorination based on principal coordinates analysis (PCoA) and permutational multivariate analysis of variance (PERMANOVA). Actinobacteria was dominant in the PE biofilms (45.57%-83.32%), while Alphaproteobacteria (34.30%-73.22%) and Gammaproteobacteria (6.46%-36.82%) were the major classes in the steel and ductile iron biofilms. The genus Rhodococcus was predominant in the PE biofilms. Rhodococcus, Pseudomonas, and Sphingomonas seemed to have a better growth advantage in the chlorinated system and display a stronger disinfectant resistance. Functional sketch prediction indicated the potential impact of pipe material and chlorination on functional pathway abundnce, possible functional pathways associated with infectious disease included. This study provides insights into the impact of pipe material and chlorination on biofilm structure and microbial community and might help to develop monitoring or maintenance strategies to protect the biosafety of the drinking water.


Assuntos
Desinfetantes , Água Potável , Microbiota , Biofilmes , Cloro , Halogenação , Microbiologia da Água , Abastecimento de Água
6.
FASEB J ; 35(7): e21701, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34143529

RESUMO

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disease. Although visceral hypersensitivity (VH) and disturbed gastrointestinal motility are typical pathophysiological features of IBS, the pathological mechanisms underlying this disease remain unclear. Serotonin system abnormalities are considered to play an important role in the pathomechanisms of IBS. Here, we hypothesize that similar alterations, including VH and colonic motility, induced by serotonin transporter (SERT) knockout result from altered serotonin signaling. We sought to determine the molecular mechanism underlying VH and colonic dysmotility induced by SERT knockout. We found that female SERT (slc6a4)-knockout (KO; ie, slc6a4-/- ) rats exhibited lower pain pressure thresholds (PPTs) than wild-type (WT; ie, slc6a4+/+ ) rats in response to colorectal distension (CRD). Significantly increased fecal pellet output and reduced concentration of serum tryptophan were observed in the female SERT KO rats. The concentrations of 5-hydroxytryptamine (5-HT) in platelet-rich plasma (PRP) and serum in SERT KO rats were lower than those in WT rats, but the numbers of enterochromaffin cells (ECs) and the concentrations of 5-HT in colon of SERT KO rats were higher than those of WT rats. Finally, increased expression levels of 5-HT1B receptors, 5-HT2C receptors, 5-HT3A receptors, 5-HT3B receptors, 5-HT6 receptors, 5-HT7 receptors, and glycosylated dopamine transporters (DATs) were found in the female SERT KO rats. We concluded that alterations in the serotonin system induced by the knockout of slc6a4 might result in VH and accelerated gastrointestinal motility in female SERT KO rats, which can be used as an animal model of IBS.


Assuntos
Colo/patologia , Motilidade Gastrointestinal , Hipersensibilidade/patologia , Síndrome do Intestino Irritável/patologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/fisiologia , Serotonina/metabolismo , Animais , Animais Geneticamente Modificados , Colo/metabolismo , Modelos Animais de Doenças , Feminino , Hipersensibilidade/etiologia , Hipersensibilidade/metabolismo , Síndrome do Intestino Irritável/etiologia , Síndrome do Intestino Irritável/metabolismo , Ratos , Ratos Sprague-Dawley
7.
Front Neurorobot ; 15: 817446, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35356155

RESUMO

Background: Lower-limb exoskeleton robots are being widely used in gait rehabilitation training for patients with stroke. However, most of the current rehabilitation robots are guided by predestined gait trajectories, which are often different from the actual gait trajectories of specific patients. One solution is to train patients using individualized gait trajectories generated from the physical parameters of patients. Hence, we aimed to explore the effect of individual gaits on energy consumption situations during gait rehabilitation training for hemiplegic patients with lower-limb exoskeleton robots. Methods: A total of 9 unilateral-hemiplegic patients were recruited for a 2-day experiment. On the first day of the experiment, the 9 patients were guided by a lower-limb exoskeleton robot, walking on flat ground for 15 min in general gait trajectory, which was gained by clinical gait analysis (CGA) method. On the other day, the same 9 patients wore the identical robot and walked on the same flat ground for 15 min in an individualized gait trajectory. The main physiological parameters including heart rate (HR) and peripheral capillary oxygen saturation (SpO2) were acquired via cardio tachometer and oximeter before and after the walking training. The energy consumption situation was indicated by the variation of the value of HR and SpO2 after walking training compared to before. Results: Between-group comparison showed that the individualized gait trajectory training resulted in an increase in HR levels and a decrease in SpO2 levels compared to the general gait trajectory training. The resulting difference had a statistical significance of p < 0.05. Conclusion: Using individualized gait guidance in rehabilitation walking training can significantly improve energy efficiency for hemiplegic patients with stroke.

8.
Sci Total Environ ; 746: 141138, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32795759

RESUMO

2,5-Dimethyl-p-phenylenediamine-1,3,5-triformylphloroglucinol covalent organic frameworks (PATP COF) were prepared and used as novel adsorbent for controlling the formation potential (FP) and reducing the toxic potential of both carbonaceous disinfection by-products (C-DBPs) and nitrogenous DBPs (N-DBPs) during their subsequent chlorination. During the PATP COF adsorption pretreatment process, the FP of C-DBPs, N-DBPs and total organic halogen (TOX) were reduced by 86.5, 75.4 and 81.1%, respectively. These removal efficiencies were significantly higher when compared with those obtained using a traditional activated carbon (AC) adsorption pretreatment process (42.7, 19.4 and 28.7%, respectively). By comprehensive toxicity calculations, a significant reduction in both the acute and chronic toxic potential of C-DBPs and N-DBPs were observed during the PATP COF adsorption process (with reduction rates of ~85 and ~ 75% observed for the C-DBPs and N-DBPs, respectively), which were comparable to the removal efficiencies observed for C-DBPs FP and N-DBPs FP by weight, suggesting the simultaneous and effective control of DBPs FP and their toxic potential. Cycling tests and stability trial also showed the excellent reusability, wide pH adaptability, and high stability of PATP COF, demonstrating its great potential application to the treatment of drinking water.


Assuntos
Desinfetantes/análise , Água Potável , Estruturas Metalorgânicas , Poluentes Químicos da Água/análise , Purificação da Água , Desinfecção , Halogenação
9.
Sci Total Environ ; 742: 140566, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32721729

RESUMO

The emergence of nitrogenous disinfection byproducts (N-DBPs) in drinking water has become a widespread concern. In this study, dichloroacetonitrile (DCAN), dicholoacetamide (DCAcAm) and trichloronitromethane (TCNM) were chosen as representatives to clarify the characteristics of N-DBP precursors in the raw waters of Taihu Lake, the Yangtze River, and Gaoyou Lake. Removal of DCAN and DCAcAm precursors must focus on nonpolar and positively charged organics, but more attention should be paid to micromolecular, polar and non-positively charged organics as TCNM precursors. Compared to molecular weight (MW) and hydrophilicity fractionation, polarity and electrical classification have higher selectivity to intercept N-DBP precursors. The properties of N-DBP precursors are relatively fixed and traceable in water systems, which could contribute to their targeted removal. Based on investigation of their characteristics, the removal efficiency and preferences of organic precursors under different processes were studied in three drinking water treatment plants (DWTPs). The TCNM precursors produced in preozonation can be effectively removed during coagulation. The cumulative removal efficiency of conventional processes on N-DBP precursors was approximately 20-30%, but O3/BAC process improved removal by about 40%. The key to improving the removal efficiency of N-DBP precursors by O3/BAC is that it can significantly remove low-MW, nonpolar, positively charged, hydrophilic and transphilic organics. In combined toxicity trials, both cytotoxicity and genotoxicity showed a synergistic effect when DCAN, DCAcAm, and TCNM coexisted, which means that low-level toxicity enhancement in the actual water merits attention. DCAN precursors dominated in the toxicity formation potential (TFP), followed by TCNM precursors. In addition, the removal rate of total N-DBP precursors may be higher than that of TFP, leading to overly optimistic evaluation of precursor removal in water treatment practice. Therefore, the removal effect on TFP must also be considered.


Assuntos
Desinfetantes , Água Potável , Poluentes Químicos da Água/análise , Purificação da Água , Desinfecção , Halogenação , Lagos , Nitrogênio
10.
Sci Total Environ ; 717: 137205, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32062283

RESUMO

Soluble microbial products (SMPs), as precursors of disinfection byproducts (DBPs) in water treatment, are composed of polysaccharides, humic acid, proteins and DNA, and have caused widespread concerned. Pyrimidine bases (cytosine and thymine) are significant nitrogenous constituents of DNA, which could pose an adverse impact on water quality during chlorination. This study focused on the correlation between relative reactivity, formation of DBPs and combined toxicity in the chlorination of a binary pyrimidine base mixture. The relative reactivities of cytosine and thymine were quite different at a low disinfectant concentration; cytosine reacted more actively with chlorine than thymine did, at the chlorine/total pyrimidine bases molar ratio = 10. The chlorination of binary pyrimidine bases can produce both carbonous DBPs (C-DBPs) and nitrogenous DBPs (N-DBPs). In particular, the total yields of trichloromethane (TCM) and trichloronitromethane (TCNM) were lower than the additive yields of monadic cytosine and monadic thymine ("monadic" refers to "separate"), whereas the total yields of haloacetic acids (HAAs) and haloacetonitriles (HANs) were promoted evidently. High reactivity of cytosine with chlorine, greater potential of cytosine to produce specific DBPs and the alkylation of transformation products of thymine may synthetically account for the diversity in total DBPs yields, especially the increased formation of HAAs and HANs. In our toxicity trial, even though the antagonistic effect predominated at fa > 0.4 (fa refers to the affected fraction), the synergism at low concentration levels could enhance the combined toxicity by promoting the yields of N-DBPs.


Assuntos
Purificação da Água , Cloro , DNA , Desinfetantes , Desinfecção , Halogenação , Pirimidinas , Água , Poluentes Químicos da Água
11.
Stud Health Technol Inform ; 264: 477-481, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31437969

RESUMO

Huntington Disease (HD) is a genetic neurodegenerative disease which leads to involuntary movements and impaired balance. These changes have been quantified using footstep pressure sensor mats such as Protokinetics' Zeno Walkway. Drawing from distances between recorded footsteps, patients' disease severity have been measured in terms of high level gait characteristics such as gait width and stride length. However, little attention has been paid to the pressure data collected during formation of individual footsteps. This work investigates the potential of classifying patient disease severity based on individual footstep pressure data using deep learning techniques. Using the Motor Subscale of the Unified HD Rating Scale (UHDRS) as the gold standard, our experiments showed that using VGG16 and similar modules can achieve classification accuracy of 89%. Image pre-processing are key steps for better model performance. This classification accuracy is compared to results based on 3D CNN (82%) and SVM (86.9%).


Assuntos
Doença de Huntington , Doenças Neurodegenerativas , Aprendizado Profundo , Marcha , Análise da Marcha , Humanos
12.
Chemosphere ; 235: 21-31, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31254778

RESUMO

The residues of pharmaceuticals and personal care products (PPCPs) in environmental waters have been widespread concerned. Metronidazole (MNZ), normally employed to treat inflammation and infection, was chosen as one model PPCP. The degradation of MNZ by chlorination could be fitted by pseudo-first-order kinetics as the observed pseudo-first-order rate constants increasing from 0.0302 min-1 to 0.2872 min-1. However, the kinetics during chloramination of MNZ followed pseudo-second-order reaction, whose estimated half-live was approximately 6-8 times longer than chlorination. The chlor(am)ination of MNZ especially formed chloroform (CF), dicholoacetamide (DCAcAm), tricholoacetamide (TCAcAm) and dichloroacetonitrile (DCAN), and their yields were overall lower under chloramination than chlorination. During chlorination, the yield of CF was increased from 0.35 ±â€¯0.02% to 2.06 ±â€¯0.12% with 1-20 chlorine/MNZ molar ratio, whereas the formations of DCAcAm, TCAcAm and DCAN increased firstly and then decreased. Increasing chloramine dosage promoted the concentrations of scheduled disinfection byproducts (DBPs). CF and TCAcAm kept continuous generation in chlor(am)ination versus reaction time. Compared with the chlorination, the chloramination of MNZ was more dependent on pH value due to the self-degradation of chloramine. Faintly acidic condition favored N-DBPs' formation in MNZ when it was subjected to chlor(am)ination. The chloramination of MNZ produced cytotoxicity and genotoxicity by 10-15 folds lower than chlorination, and DCAN formed during chloramination dominated both DBPs' yields and toxicity contribution. Opposite to chlorination, the integrated toxicity of MNZ during chloramination varied linearly versus N-DBPs' yields.


Assuntos
Cloraminas/química , Desinfecção/métodos , Halogenação , Metronidazol/toxicidade , Purificação da Água/métodos , Acetonitrilas , Cinética , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
13.
Int J Ophthalmol ; 10(4): 624-631, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28503438

RESUMO

AIM: To compare visual quality after femtosecond laser in situ keratomileusis (FS-LASIK), between the coaxially sighted corneal light reflex (CSCLR) group and conventional ablation line of sight (LOS) group. METHODS: In total, 243 eyes (122 patients) were treated with centration on the CSCLR (visual axis) and 238 eyes (119 patients) treated with centration on the pupil center (LOS). Postoperative outcomes [uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA)], safety index, efficacy index, refractive outcome, ablation center distance from the visual axis, corneal high-order aberrations, subjective discomfort glare and shadowing incidence rate, and contrast sensitivity at 1, 3, and 6mo were measured and compared. RESULTS: The mean age was 27.77±7.1y in the CSCLR group and 26.03±7.70y in the LOS group. Preoperatively, the manifest refraction spherical equivalent (MRSE) was -6.68±2.60 D in the CSCLR group and -6.65±2.68 D in the LOS group. The postoperative UCVA, BSCVA, MRSE (-0.03±0.263 D in the CSCLR group, -0.05±0.265 D in the LOS group), efficacy index (1.04, 1.03), and safety index (1.09, 1.08) were not significantly different between the groups (all P>0.05). In total, 3% lost one line and more of BSCVA in the CSCLR group, as 9% in the LOS group postoperatively (P<0.05). The ablation center deviation was 0.20±0.15 mm from the visual axis (Pentacam system default setting; range, 0-0.75 mm) in the CSCLR group, and 0.43±0.22 mm (range, 0-1.32 mm) in the LOS group (P<0.0001). Statistically significant greater augmentation of total corneal higher-order aberrations (0.15±0.10 µm and 0.20±0.12 µm respectively, P=0.03) and vertical and horizontal coma (P<0.0001) were noted in the LOS group. Subjective discomfort glare and shadowing incidence rates were 8.59% and 17.5% in the CSCLR and LOS groups, respectively (P<0.05). The 1-month postoperative contrast sensitivity visual acuity in the CSCLR group was significantly higher than that in the LOS group on contrast (100%, 25%, 10%) with a dark background, but there was no significant difference between the groups at 3 or 6m. CONCLUSION: Myopic LASIK centered on the CSCLR achieves significantly lower induction of loss of BSCVA, corneal high-order aberrations, and lower risk of subjective discomfort glare and shadowing, and lower decline in early contrast sensitivity by comparison with centration on the LOS, giving advantages in visual quality postoperatively.

14.
J Colloid Interface Sci ; 478: 263-70, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27309946

RESUMO

A direct solid state Z-scheme photocatalytic system was fabricated by assembling two-dimensional (2D) g-C3N4 nanosheets (CNNS) and titania nanosheets (TNS), which were obtained from the delamination of their corresponding layered precursors. By introducing TNS, the interlayer restacking of CNNS was effectively prohibited, forming uniform CNNS/TNS composites. The tightly contacted CNNS/TNS interface promoted the charge transfer and therefore improved the separation ratio of photogenerated electron-hole pairs. The photocatalytic performance of CNNS/TNS in various mass ratios was investigated for dye degradation, and the degradation rate of optimal sample 0.7CNNS/0.3TNS was 2.34 and 48.5 times higher than those of proton flocculated pure CNNS and TNS, respectively. Superoxide radicals and hydroxyl radicals were determined as the main active species by the quenching experiment. Moreover, the enhanced generation of superoxide radicals and hydroxyl radicals was confirmed by the absorption spectra of nitroblue tetrazolium and the photoluminescence spectra of 2-hydroxy terephthalic acid, respectively. Finally, we proposed a possible Z-scheme mechanism based on the theoretical calculation and the experimental results.

15.
Lasers Med Sci ; 30(1): 127-33, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25048854

RESUMO

The aim of this study was to investigate whether pre-exposure to low-power laser irradiation can provoke an effect on cellular protection in the rat retina. The right eyes of 40 rats were exposed to a 3-mm diode laser beam for 1 min in different light intensities and different experimental sets: group A low power of 60 mW (34.27 J/cm(2) on the retina in consideration of the energy losses along the optical pathway) prior to high power of 80 mW (44.88 J/cm(2) on the retina in consideration of the energy losses along the optical pathway), group B high power, group C low power, group D (the left eyes from the counterpart of group A) and group E (untreated rat eyes) as controls. Morphological retinal change retinas were assessed using light microscopy and/or transmission electron microscopy. Heat shock protein (Hsp) 70 and cleaved caspase 3 protein expression were analyzed by immunohistochemical staining and Western blot. Cellular injury was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. Hsp 70 expression in the inner plexiform layer and the outer plexiform layer in group A were 73.09 ± 6.49 and 78.03 ± 3.05%, respectively, which was significantly higher (P < 0.05) than those observed in group B (59.07 ± 1.40 and 32.25 ± 4.26%, respectively). The Hsp70/ß-actin ratio was 0.49 ± 0.06 in group C, which was significantly higher (P < 0.05) than that of group B (0.27 ± 0.04). Cleaved caspase 3 expression in group C both was significantly lower than that observed in group B. TUNEL staining showed that positive cells in the outer nuclear layer and inner nuclear layer in group A were significantly lower than those of group B. Pre-exposure to a 60-mW (34.27 J/cm(2) on the retina) power laser irradiation stimulates a hyperexpression of Hsp70 together with a hypoexpression of cleaved caspase 3 in rat retina, which may suggest a cellular protective effect.


Assuntos
Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade , Degeneração Macular/radioterapia , Retina/efeitos da radiação , Actinas/metabolismo , Animais , Caspase 3/metabolismo , Citoproteção , Proteínas de Choque Térmico HSP70/metabolismo , Ratos , Ratos Endogâmicos BN , Retina/patologia
16.
Int J Ophthalmol ; 7(2): 273-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24790869

RESUMO

AIM: To evaluate differences in flap thickness resulting from use of an Alcon Wavelight FS200 femtosecond laser and a MORIA SBK microkeratome when making a 110-µm-thick corneal flap and to identify the potential factors that affect corneal flap thickness. METHODS: A prospective case study was performed on 120 eyes of 60 patients who were divided into two groups for LASIK, each group consisting of 60 eyes (30 patients). The corneal flaps were created using an Alcon Wavelight FS200 femtosecond laser or a MORIA SBK microkeratome. The central corneal flap thickness was calculated by subtraction pachymetry. Age, central corneal thickness (CCT), spherical equivalent refraction, mean keratometry, and corneal diameter were recorded preoperatively for analysis. RESULTS: Cutting of all flaps was easily performed without intraoperative complications. In the Alcon Wavelight FS200 femtosecond laser group, the mean right and left corneal flap thicknesses were 114.0±6.6 µm (range: 98-126) and 111.4±7.6 µm (range: 98-122), respectively. The difference (2.6±9.1 µm) in the corneal flap thickness between the right and left eyes was not significant (t=1.59, P=0.12). Stepwise regression analysis indicated that the resulting corneal flap thickness was unrelated to the patient's age, preoperative CCT, spherical equivalent refraction, mean keratometry, or corneal diameter. In the MORIA SBK microkeratome group, the mean right and left corneal flap thicknesses were 110.6±7.4 µm (range: 97-125 µm) and 108.2±6.1 µm (range: 78-123 µm), respectively. The difference in the corneal flap thickness between the right and left eyes (2.4±6.5µm) was not significant (t=2.039, P=0.0506). The corneal flap thickness was positively correlated with the preoperative CCT through stepwise regression analysis (r=0.297, P=0.021). The corneal flap thickness was not related to age, spherical equivalent refraction, mean keratometry, or corneal diameter. The corneal flap thickness was estimated using the following equation: Tflap=67.77+0.076 CCT (F=5.63, P=0.021). CONCLUSION: Both the Alcon Wavelight FS200 femtosecond laser and the MORIA SBK microkeratome produced 110-µm-thick corneal flaps. The central corneal flap thickness was positively correlated with the preoperative CCT in MORIA SBK microkeratome surgery.

17.
Zhonghua Yan Ke Za Zhi ; 49(4): 305-8, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23900088

RESUMO

OBJECTIVE: To determine flap thickness variation in 110 µm thickness flap made by FS200 femtosecond laser and sub-Bowman keratomileusis (SBK) microkeratome for studying the potential factors that affect the flap thickness. METHODS: It was a case-control study. Sixty patients were divided into two groups for laser in situ keratomileusis. The corneal flaps were made by using Alcon Wavelight FS200 femtosecond laser or MORIA SBK microkeratome. Central corneal flap thickness was calculated by subtraction pachymetry. Age, central corneal thickness (CCT), spherical equivalent refraction, mean keratometry and corneal diameter were recorded preoperatively for statistics. RESULTS: This study comprised 120 eyes of 60 patients; 60 eyes were treated with each group. In Alcon Wavelight FS200 femtosecond laser group, the mean corneal flap thickness in the right and left eyes was (114.0 ± 6.6) and (111.4 ± 7.6) µm, respectively. The difference in corneal flap thickness between the right eye and the left eye (2.6 ± 9.1) µm was not statistically significant (t = 1.59, P = 0.12). Corneal flap thickness had no relationship with the age, preoperatively CCT, spherical equivalent refraction, corneal curvature and corneal diameter through stepwise regression analysis. In SBK microkeratome group, the mean corneal flap thickness in the right eye and the left eye was (110.6 ± 7.4) and (108.2 ± 6.1) µm respectively. The difference in corneal flap thickness between the right eye and the left eye (2.4 ± 6.6) µm was not statistically significant (t = 2.019, P = 0.054). Corneal flap thickness was positively correlated with preoperative CCT through stepwise regression analysis (r = 0.29, P = 0.021). Corneal flap thickness equaled to 67.77 + 0.076· CCT (F = 5.63, P = 0.021). Corneal flap thickness had no relationship with the age, spherical equivalent refraction, corneal curvature and corneal diameter. CONCLUSIONS: Both FS200 femtosecond laser and SBK microkeratome can be used for making a good 110 µm thickness flap. Central corneal flap thickness was positively correlated with the preoperative CCT using the SBK microkeratome.


Assuntos
Córnea/cirurgia , Lasers de Excimer , Miopia/cirurgia , Adolescente , Adulto , Substância Própria/cirurgia , Feminino , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ , Masculino , Pessoa de Meia-Idade , Retalhos Cirúrgicos , Adulto Jovem
18.
Int J Ophthalmol ; 6(2): 141-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23638412

RESUMO

AIM: To evaluate the effects of intensive control of blood glucose and blood pressure on microvascular complications in patients with type II diabetes by comparing the therapeutic effects of intensive and standard treatment in patients with type II diabetes. METHODS: A total of 107 patients with type II diabetes were randomly assigned into intensive and standard treatment groups. Patients in the intensive treatment group received preterax (perindopril/ indapamide) to control blood pressure, and gliclazide (diamicron) MR to control blood glucose. Patients in the standard treatment group received routine medications or placebo. Urinary microalbumin (UMA), urinary creatinine (UCR), the UMA/UCR ratio, and visual acuity were monitored according to the study design of the ADVANCE trial. Direct ophthalmoscopy and seven-field stereoscopic retinal photography were used to examine the fundi at baseline, and repeated after 5 years of treatment. RESULTS: The characteristics of patients in both groups were well balanced at baseline. After 5 years of treatment, visual acuity was found to be decreased in the standard group (P=0.04), but remained stable in the intensive group. The severity of diabetic retinopathy had not progressed in patients in the intensive group, but had deteriorated in the standard group (P=0.0006). The UMA/UCR ratio was not obviously changed in patients in the intensive group, whereas it was significantly increased in the standard group (P=0.00). CONCLUSION: Intensive control of blood glucose and blood pressure can decrease the incidence or slow the progression of microvascular complications in patients with type II diabetes, and maintain stable vision.

19.
Mol Vis ; 18: 2380-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23049238

RESUMO

PURPOSE: To investigate the biologic effect of an 810 nm diode laser on the induction of heat shock protein 70 (Hsp70) in choroid-retinal endothelial cells in vitro. METHODS: Cultured rhesus macaque choroid-retinal endothelial cells (RF/6A) were irradiated using an 810 nm diode laser (spot size, 10 mm; duration, 60 s; power, 400-1,500 mW). Cell viability was assessed by annexin V- fluorescein isothiocyanate (FITC) and propidium iodide flow cytometric assay. Hsp70 expression was determined by western blot at 6, 12, 18, 24, and 48 h following laser exposure. Intracellular distribution of Hsp70 was examined by immunofluorescence staining. RESULTS: The laser-induced cell injury threshold was found to be at a power of 1,100 mW power (fluence, 84.08 J/cm(2)), above which there was significant cell death. Under this power, Hsp70 expression elevated obviously and was stronger at 600-1,000 mW power settings (fluences, 45.86-76.43 J/cm(2)). The expression of Hsp70 peaked at 12-18 h postirradiation, and returned to baseline by 48 h. Immunofluorescence staining indicated the induced Hsp70 expression in both the cytoplasm and the nucleus. CONCLUSIONS: Subthreshold 810 nm diode laser exposure can induce Hsp70 hyperexpression from 12 to 18 h postirradiation in cultured choroid-retinal endothelial cells without obvious cell death. The results could be useful for investigating and designing more effective laser therapies.


Assuntos
Corioide/efeitos da radiação , Células Endoteliais/efeitos da radiação , Proteínas de Choque Térmico HSP70/metabolismo , Lasers Semicondutores , Retina/efeitos da radiação , Animais , Anexina A5 , Linhagem Celular , Núcleo Celular/efeitos da radiação , Núcleo Celular/ultraestrutura , Sobrevivência Celular/efeitos da radiação , Corioide/citologia , Corioide/metabolismo , Citoplasma/efeitos da radiação , Citoplasma/ultraestrutura , Relação Dose-Resposta à Radiação , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Imunofluorescência , Expressão Gênica/efeitos da radiação , Proteínas de Choque Térmico HSP70/genética , Macaca , Retina/citologia , Retina/metabolismo
20.
Zhonghua Yan Ke Za Zhi ; 47(6): 531-8, 2011 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-21914269

RESUMO

OBJECTIVE: To evaluate the efficacy, safety and stability of three kinds of phakic intraocular lens implantation for the correction of high myopia. METHODS: This study included 208 eyes of 110 patients with a mean age of 31 years (21 - 53) from December 2003 to December 2009. Angle-supported lens (Phakic 6H, OII) were inserted into 113 eyes, iris-fixated lens (Artisan, OPHTEC) were inserted into 53 eyes and implantable contact lens (ICL) (V4, STAAR) were inserted into 41eyes. The average follow-up time of the three groups were 54.0 months (3 - 72 months), 15.7 months (3 - 24 months) and 7.2 months (3 - 15 months) respectively. RESULTS: At 3 months and 12 months, the efficacy indexes of the three groups were all above 1.00. Only the angle-supported group was followed up to 72 months postoperatively when the efficacy index dropped to 0.85, but still UCVA was 1.0 (20/20) or better in 16% eyes and 0.5 (20/40) or better in 85% eyes. The safety indexes of the three groups were always above 1.00 during the follow up. In the angle-supported group, 46% eyes were within ± 0.50 D of the desired refraction and 68% eyes were within ± 1.00 D at 5 years postoperatively. In the iris-fixated group, 78% eyes were within ± 0.50 D of the desired refraction and 100% eyes were within ± 1.00 D at 1 years postoperatively. In the ICL group, 95% eyes were within ± 0.50 D of the desired refraction and 100% eyes were within ± 1.00 D at 3 months postoperatively. No statistically significant differences were found between preoperative and 3-month postoperative endothelial cell density in the ICL group. Also, there was no statistically significant reduction in endothelial cell density at 1 years in the iris-fixated group. However, when preoperative and 5-year postoperative measurements were compared in the angle-supported group, the total decrease in cell density is statistically significant (t = 9.769, P = 0.000). 16 eyes developed high IOP within 1 month postoperatively which resolved after intervention. In the three groups (angle-supported, iris-fixated and ICL), the most common complications were pupil ovalization, iris atrophy plus pigment dispersion and lens opacification respectively. CONCLUSION: Although phakic IOL implantation is predictable and safe for treatment of high myopia in short-term, the long-term complications should be concerned and treated well.


Assuntos
Implante de Lente Intraocular/instrumentação , Miopia/cirurgia , Adulto , Segurança de Equipamentos , Feminino , Humanos , Implante de Lente Intraocular/métodos , Masculino , Pessoa de Meia-Idade , Lentes Intraoculares Fácicas/classificação , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
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