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PURPOSE: To represent 24-2 visual field (VF) losses of individual patients using a hybrid approach of archetypal analysis (AA) and fuzzy c-means (FCM) clustering. METHODS: In this multicenter retrospective study, we classified characteristic patterns of 24-2 VF using AA and decomposed them with FCM clustering. We predicted the change in mean deviation (MD) through supervised machine learning from decomposition coefficient change. In addition, we compared the areas under the receiver operating characteristic curves (AUCs) of the decomposition coefficient slopes to detect VF progression using three criteria: MD slope, Visual Field Index slope, and pointwise linear regression analysis. RESULTS: We identified 16 characteristic patterns (archetypes or ATs) of 24-2 VF from 132,938 VFs of 18,033 participants using AA. The hybrid approach using FCM revealed a lower mean squared error and greater correlation coefficient than the AA single approach for predicting MD change (all P ≤ 0.001). Three of 16 AUCs of the FCM decomposition coefficient slopes outperformed the AA decomposition coefficient slopes in detecting VF progression for all three criteria (AT5, superior altitudinal defect; AT10, double arcuate defect; AT13, total loss) (all P ≤ 0.028). CONCLUSION: A hybrid approach combining AA and FCM to analyze 24-2 VF can visualize VF tests in characteristic patterns and enhance detection of VF progression with lossless decomposition.
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Progresión de la Enfermedad , Glaucoma , Campos Visuales , Humanos , Campos Visuales/fisiología , Estudios Retrospectivos , Femenino , Masculino , Glaucoma/diagnóstico , Glaucoma/fisiopatología , Persona de Mediana Edad , Lógica Difusa , Análisis por Conglomerados , Pruebas del Campo Visual/métodos , Anciano , Curva ROC , Área Bajo la CurvaRESUMEN
PURPOSE: This study aimed to predict future visual field tests using a bidirectional gated recurrent unit (Bi-GRU) and assess its performance based on the number of input visual field tests and the prediction time interval. MATERIALS AND METHODS: This study included patients who underwent visual field tests at least four times at five university hospitals between June 2004 and April 2022. All data were accessed in October 2022 for research purposes. In total, 23,517 eyes with 185,858 visual field tests were used as the training dataset, and 1,053 eyes with 9,459 visual field tests were used as the test dataset. The Bi-GRU architecture was designed to take a variable number of visual field tests, ranging from 3 to 80, as input and predict visual field tests at the desired arbitrary time point. It generated the mean deviation (MD), pattern standard deviation (PSD), Visual Field Index (VFI), and total deviation value (TDV) for 54 test points. To analyze the model performance, the mean absolute error between the actual and predicted values was calculated and analyzed for glaucoma severity, number of input visual field tests, and prediction time interval. RESULTS: The prediction errors of the Bi-GRU model for MD, PSD, VFI, and TDV ranged from 1.20 to 1.68 dB, 0.95 to 1.16 dB, 3.64 to 4.51%, and 2.13 to 2.60 dB, respectively, depending on the number of input visual field tests. Prediction errors tended to increase as the prediction time interval increased; however, the difference was not statistically significant. As the severity of glaucoma worsened, the prediction errors significantly increased. CONCLUSION: In clinical practice, the Bi-GRU model can predict future visual field tests at the desired time points using three or more previous visual field tests.
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Glaucoma , Pruebas del Campo Visual , Campos Visuales , Humanos , Campos Visuales/fisiología , Pruebas del Campo Visual/métodos , Glaucoma/fisiopatología , Glaucoma/diagnóstico , Femenino , Masculino , Persona de Mediana Edad , Anciano , Adulto , Redes Neurales de la ComputaciónRESUMEN
Per- and poly-fluoroalkyl substances (PFAS) are synthetic chemicals widely used in everyday products, causing elevated concentrations in drinking water and posing a global challenge. While adsorption methods are commonly employed for PFAS removal, the substantial cost and environmental footprint of commercial adsorbents highlight the need for more cost-effective alternatives. Additionally, existing adsorbents exhibit limited effectiveness, particularly against diverse PFAS types, such as short-chain PFAS, necessitating modifications to enhance adsorption capacity. Biochar can be considered a cost-effective and eco-friendly alternative to conventional adsorbents. With abundant feedstocks and favorable physicochemical properties, biochar shows significant potential to be applied as an adsorbent for removing contaminants from water. Despite its effectiveness in adsorbing different inorganic and organic contaminants from water environments, some factors restrict its effective application for PFAS adsorption. These factors are related to the biochar properties, and characteristics of PFAS, as well as water chemistry. Therefore, some modifications have been introduced to overcome these limitations and improve biochar's adsorption capacity. This review explores the preparation conditions, including the pyrolysis process, activation, and modification techniques applied to biochar to enhance its adsorption capacity for different types of PFAS. It addresses critical questions about the adsorption performance of biochar and its composites, mechanisms governing PFAS adsorption, challenges, and future perspectives in this field. The surge in research on biochar for PFAS adsorption indicates a growing interest, making this timely review a valuable resource for future research and an in-depth exploration of biochar's potential in PFAS remediation.
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Carbón Orgánico , Fluorocarburos , Contaminantes Químicos del Agua , Purificación del Agua , Carbón Orgánico/química , Adsorción , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Fluorocarburos/químicaRESUMEN
This study aimed to develop a new index, the average curvature ratio (ACR), to represent the optic nerve head (ONH) tilting and investigate its clinical relevance. Myopic eyes were included and divided into two subgroups: flat ONH (ACR < 1.0) and convex ONH (ACR ≥ 1.0). The occurrences of central and peripheral visual field (VF) defects were compared between the two groups. A total of 375 myopic eyes were recruited, and 231 and 144 eyes were included in the flat and convex ONH groups, respectively. Central scotoma occurred more frequently in the flat ONH group. According to the Patella-Anderson criteria, the number of eyes with central scotoma was 103 (44.6%) in the flat and 44 (30.6%) in the convex ONH groups (p = 0.009). According to Kook's criteria, the number of eyes with central scotoma was 122 (52.8%) in the flat and 50 (34.7%) in the convex ONH groups (p < 0.001). Peripheral scotoma was not significantly different between the groups. In the correlation analysis, the ACR was positively correlated with spherical equivalence, but not with axial length or central corneal thickness. The ACR reflects the degree of the ONH tilt and is a good index for estimating central VF damage in myopic eyes.
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PURPOSE: This study aimed to evaluate the 1-year surgical outcomes of XEN45 gel stent implantation with an open conjunctiva approach in patients with open-angle glaucoma (OAG). METHODS: This retrospective cohort study included 19 eyes of 19 patients who underwent XEN45 gel stent implantation with an open conjunctival approach. Surgical success was defined by intraocular pressure (IOP) ≤18 mmHg and one of the following: IOP reduction ≥30% or reduction of two glaucoma medications with final IOP if baseline IOP ≤18 mmHg. The cumulative probability of success rate was analyzed using Kaplan-Meier survival analysis. Cox proportional hazard regression analysis was used to assess prognostic factors for surgical failure. RESULTS: IOP reduced from 32.37 ± 12.08 mmHg preoperatively to 15.14 ± 2.25 mmHg at 1 year (p = 0.001). The number of glaucoma medication reduced from 3.89 ± 0.32 preoperatively to 0.86 ± 1.35 at 1 year (p = 0.001). The success rates were 78.9% at 6 months and 73.7% at 1 year. Eyes with bleb horizontal extent ≥2 clock hours at 1 month postoperatively had a significantly higher success rate (log-rank test, p < 0.001). Greater bleb horizontal extent at 2 weeks and 1 month postoperatively was associated with a lower surgical failure rate (2 weeks: hazard ratio, 0.119; p = 0.024; 1 month: hazard ratio, 0.046; p = 0.007). Bleb needling and additional glaucoma surgeries were necessary in 10 (52.6%) and five eyes (26.3%), respectively. CONCLUSIONS: XEN45 gel stent implantation with the open conjunctiva approach is effective in reducing IOP and glaucoma medication for over 1 year in patients with OAG.
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Although deep learning architecture has been used to process sequential data, only a few studies have explored the usefulness of deep learning algorithms to detect glaucoma progression. Here, we proposed a bidirectional gated recurrent unit (Bi-GRU) algorithm to predict visual field loss. In total, 5413 eyes from 3321 patients were included in the training set, whereas 1272 eyes from 1272 patients were included in the test set. Data from five consecutive visual field examinations were used as input; the sixth visual field examinations were compared with predictions by the Bi-GRU. The performance of Bi-GRU was compared with the performances of conventional linear regression (LR) and long short-term memory (LSTM) algorithms. Overall prediction error was significantly lower for Bi-GRU than for LR and LSTM algorithms. In pointwise prediction, Bi-GRU showed the lowest prediction error among the three models in most test locations. Furthermore, Bi-GRU was the least affected model in terms of worsening reliability indices and glaucoma severity. Accurate prediction of visual field loss using the Bi-GRU algorithm may facilitate decision-making regarding the treatment of patients with glaucoma.
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Glaucoma , Campos Visuales , Humanos , Reproducibilidad de los Resultados , Ojo , Algoritmos , Glaucoma/diagnósticoRESUMEN
INTRODUCTION: The purpose of this study was to compare the characteristics of filtering bleb with anterior segment optical coherence tomography (AS-OCT) according to amniotic membrane transplantation (AMT). METHODS: One hundred and sixteen eyes of 103 glaucoma patients who underwent trabeculectomy with (AMT group; 85 eyes) or without AMT (control group; 31 eyes) were included. Intrableb parameters were evaluated with AS-OCT. Surgical success was defined as an intraocular pressure (IOP) ≤18 mm Hg and IOP reduction ≥20% without medication at the time of AS-OCT examination. Logistic regression analyses were performed to determine factors associated with IOP control. RESULTS: In the eyes with successful IOP control, the fluid-filled space area, score, and height were greater for the AMT group than the control group (all ps < 0.001), while stripping layer thickness was greater and bleb wall reflectivity was lower for the control group than the AMT group (all ps < 0.001). Surgical success in the AMT group was associated with greater fluid-filled space score, lower bleb wall reflectivity, and microcyst formation (odds ratio [OR] = 8.016, 0.913, and 16.202, respectively, all ps ≤ 0.041). Lower bleb wall reflectivity alone was associated with surgical success in the control group (OR = 0.815, p = 0.019). CONCLUSION: The extent of the fluid-filled space was associated with successful IOP control after trabeculectomy with AMT. Hyporeflective bleb wall was associated with successful IOP control in AMT and control groups.
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Glaucoma , Trabeculectomía , Humanos , Trabeculectomía/métodos , Tomografía de Coherencia Óptica/métodos , Segmento Anterior del Ojo/diagnóstico por imagen , Amnios , Glaucoma/diagnóstico , Glaucoma/cirugía , Presión IntraocularRESUMEN
INTRODUCTION: Little has been known about the intrableb structures associated with bleb function after trabeculectomy with amniotic membrane transplantation (AMT). The aim of this study is to analyze the characteristics of intrableb structures using anterior segment optical coherence tomography (AS-OCT) after trabeculectomy with AMT. METHODS: A total of 68 eyes of 68 patients with primary open-angle glaucoma who underwent trabeculectomy with AMT were included. Surgical success was defined as intraocular pressure (IOP) ≤ 18 mmHg and IOP reduction of ≥ 20% without medication on AS-OCT examination. Intrableb parameters, including bleb height, bleb wall thickness, striping layer thickness, bleb wall reflectivity, fluid-filled space score, fluid-filled space height, and microcyst formation were evaluated using AS-OCT. Logistic regression analysis was performed to determine factors associated with IOP control. RESULTS: Of the 68 eyes, 56 eyes were assigned to the success group and 12 eyes to the failure group. In the success group, bleb height (P = 0.009), bleb wall thickness (P = 0.001), striping layer thickness (P = 0.001), fluid-filled space score (P = 0.001), and frequency of microcyst formation (P = 0.001) were greater than those in the failure group. Bleb wall reflectivity was higher in the failure group than in the success group (P < 0.001). In the univariate logistic regression analysis, previous cataract surgery was significantly associated with surgical failure (odds ratio = 5.769, P = 0.032). CONCLUSION: A posteriorly extending fluid-filled space, tall bleb with low reflectivity, and thick striping layer were characteristics of successful filtering blebs after trabeculectomy with AMT.
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Glaucoma de Ángulo Abierto , Glaucoma , Trabeculectomía , Humanos , Trabeculectomía/métodos , Glaucoma/diagnóstico por imagen , Glaucoma/cirugía , Tomografía de Coherencia Óptica/métodos , Segmento Anterior del Ojo/diagnóstico por imagen , Glaucoma de Ángulo Abierto/diagnóstico por imagen , Glaucoma de Ángulo Abierto/cirugía , Amnios , Presión IntraocularRESUMEN
BACKGROUND: Radical cystectomy is a major urological procedure with high morbidity and mortality. The chart-derived frailty index (CFI), a measure of preoperative frailty, can be calculated by using demographic and routine laboratory variables. We assessed the impact of CFI on 1-year mortality after radical cystectomy. METHODS: This retrospective study included patients with bladder cancer who underwent radical cystectomy between 2007 and 2021. The CFI was calculated as the sum of the presence of the following parameters: age > 70 years, body mass index < 18.5 kg/m2, hematocrit < 35%, albumin < 3.4 g/dL, and creatinine > 2.0 mg/dL. Patients were divided into those with low (0-2) and high (3-5) CFI. The 1-year, all-cause and cancer-specific mortalities after radical cystectomy were evaluated. RESULTS: Of the 1004 patients, 914 (91.0%) had a low CFI and 90 (9.0%) had a high CFI. The 1-year, all-cause mortality in the low and high CFI groups was 12.0% and 27.8%, respectively (P < 0.001). Multivariate Cox regression analysis revealed that high CFI (P < 0.001), tumor stage (P = 0.003), and red blood cell transfusion amount (P < 0.001) were significantly associated with 1-year, all-cause mortality after radical cystectomy. Kaplan-Meier survival analysis demonstrated significantly different 1-year, all-cause and cancer-specific mortalities after radical cystectomy between patients with a high CFI and those with a low CFI (log-rank test, both P < 0.001). CONCLUSIONS: High CFI is associated with higher 1-year mortality after radical cystectomy, suggesting that the CFI can effectively predict mortality after radical cystectomy.
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Fragilidad , Neoplasias de la Vejiga Urinaria , Humanos , Anciano , Cistectomía , Estudios Retrospectivos , Fragilidad/complicaciones , Tasa de Supervivencia , Neoplasias de la Vejiga Urinaria/patologíaRESUMEN
Conventional desalination membrane technologies, although offer portable drinking water, are still energy-intensive processes. This paper proposes a potentially new approach for performing water desalination and purification by utilizing the reversible interaction of carbon dioxide (CO2) with nucleophilic aminesâreminiscent of the Solvay process. Based on our model studies with small molecules, CO2-responsive amphiphilic insoluble diamines were prepared, characterized, and applied in the formation of soda and ammonium chloride upon exposure to ambient CO2 (1 atm), thus removing chloride ions from model and real seawater. This ion-exchange process and separation of chloride from the aqueous phase are spontaneous in the presence of CO2 without the need for external energy sources. We demonstrate a flow system to envisage energy-efficient CO2-mediated desalination and simultaneous carbon capture and sequestration.
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To evaluate whether an impaired anterior visual pathway (retinal structures with microvasculature) is associated with underlying beta-amyloid (Aß) pathologies in patients with Alzheimer's disease dementia (ADD) and mild cognitive impairment (MCI), we compared retinal structural and vascular factors in each subgroup with positive or negative amyloid biomarkers. Twenty-seven patients with dementia, thirty-five with MCI, and nine with cognitively unimpaired (CU) controls were consecutively recruited. All participants were divided into positive Aß (A+) or negative Aß (A-) pathology based on amyloid positron emission tomography or cerebrospinal fluid Aß. The retinal circumpapillary retinal nerve fiber layer thickness (cpRNFLT), macular ganglion cell/inner plexiform layer thickness (mGC/IPLT), and microcirculation of the macular superficial capillary plexus were measured using optical coherence tomography (OCT) and OCT angiography. One eye of each participant was included in the analysis. Retinal structural and vascular factors significantly decreased in the following order: dementia < MCI < CU controls. The A+ group had significantly lower microcirculation in the para- and peri-foveal temporal regions than did the A-. However, the structural and vascular parameters did not differ between the A+ and A- with dementia. The cpRNFLT was unexpectedly greater in the A+ than in the A- with MCI. mGC/IPLT was lower in the A+ CU than in the A- CU. Our findings suggest that retinal structural changes may occur in the preclinical and early stages of dementia but are not highly specific to AD pathophysiology. In contrast, decreased temporal macula microcirculation may be used as a biomarker for the underlying Aß pathology.
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Patau syndrome (trisomy 13) is a severe disorder associated with multiple systemic defects. Patau syndrome is commonly associated with ocular abnormalities but rarely associated with congenital glaucoma. To obtain a better surgical view, palatoplasty requires neck extension during surgery. The intraocular pressure (IOP) of patients with Patau syndrome can increase owing to the neck extension position while undergoing palatoplasty, particularly in those with congenital glaucoma. Here, we describe a case with increased IOP measured using a rebound tonometer during palatoplasty in a pediatric patient with Patau syndrome and congenital glaucoma. This case shows that it may be important to reduce the degree of neck extension and shorten the operation time to minimize any increase in the IOP during palatoplasty in pediatric patients with Patau syndrome accompanied by congenital glaucoma.
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Fisura del Paladar , Glaucoma , Humanos , Niño , Presión Intraocular , Síndrome de la Trisomía 13 , Tonometría Ocular , Glaucoma/cirugía , Glaucoma/congénito , Fisura del Paladar/cirugíaRESUMEN
Close monitoring of central visual field (VF) defects with 10-2 VF helps prevent blindness in glaucoma. We aimed to develop a deep learning model to predict 10-2 VF from wide-field swept-source optical coherence tomography (SS-OCT) images. Macular ganglion cell/inner plexiform layer thickness maps with either wide-field en face images (en face model) or retinal nerve fiber layer thickness maps (RNFLT model) were extracted, combined, and preprocessed. Inception-ResNet-V2 was trained to predict 10-2 VF from combined images. Estimation performance was evaluated using mean absolute error (MAE) between actual and predicted threshold values, and the two models were compared with different input data. The training dataset comprised paired 10-2 VF and SS-OCT images of 3,025 eyes of 1,612 participants and the test dataset of 337 eyes of 186 participants. Global prediction errors (MAEpoint-wise) were 3.10 and 3.17 dB for the en face and RNFLT models, respectively. The en face model performed better than the RNFLT model in superonasal and inferonasal sectors (P = 0.011 and P = 0.030). Prediction errors were smaller in the inferior versus superior hemifields for both models. The deep learning model effectively predicted 10-2 VF from wide-field SS-OCT images and might help clinicians efficiently individualize the frequency of 10-2 VF in clinical practice.
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Aprendizaje Profundo , Glaucoma , Humanos , Tomografía de Coherencia Óptica/métodos , Campos Visuales , Fibras Nerviosas , Células Ganglionares de la Retina , Glaucoma/diagnóstico por imagen , Escotoma , Pruebas del Campo Visual/métodos , Presión IntraocularRESUMEN
Although hydraulic accumulators play a vital role in the hydraulic system, they face the challenges of being broken by continuous abnormal pulsating pressure which occurs due to the malfunction of hydraulic systems. Hence, this study develops anomaly detection algorithms to detect abnormalities of pulsating pressure for hydraulic accumulators. A digital pressure sensor was installed in a hydraulic accumulator to acquire the pulsating pressure data. Six anomaly detection algorithms were developed based on the acquired data. A threshold averaging algorithm over a period based on the averaged maximum/minimum thresholds detected anomalies 2.5 h before the hydraulic accumulator failure. In the support vector machine (SVM) and XGBoost model that distinguish normal and abnormal pulsating pressure data, the SVM model had an accuracy of 0.8571 on the test set and the XGBoost model had an accuracy of 0.8857. In a convolutional neural network (CNN) and CNN autoencoder model trained with normal and abnormal pulsating pressure images, the CNN model had an accuracy of 0.9714, and the CNN autoencoder model correctly detected the 8 abnormal images out of 11 abnormal images. The long short-term memory (LSTM) autoencoder model detected 36 abnormal data points in the test set.
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Redes Neurales de la Computación , Máquina de Vectores de Soporte , Factores de Tiempo , AlgoritmosRESUMEN
PURPOSE: Robotic prostatectomy is the most common surgical approach for treating prostate cancer. Patients undergoing robotic prostatectomy may have bullae, which may rupture leading to pneumothorax. We evaluated the incidence of pneumothorax due to preoperative bullae rupture in robotic prostatectomy. METHODS: A large retrospective study of patients who underwent robotic prostatectomy between 2009 and 2021 was conducted. Bullae were detected using chest computed tomography. Pneumothorax was detected using a chest X-ray. The primary outcome was the incidence of pneumothorax due to bullae rupture. Secondary outcomes were the prevalence of preoperative bullae and the evaluation of postoperative outcomes, including length of hospital stay, intensive care unit admission rate, and prolonged intensive care unit stay (> 2 days). RESULTS: A total of 6605 patients were included. The prevalence of preoperative bullae was 3.0% (196/6,605). There was no incidence of pneumothorax due to bullae rupture. No significant difference in the incidences of pneumothorax between patients with and without bullae (0/196 vs. 2/6,409, P > 0.999) was observed. In addition, length of hospital stay, intensive care unit admission rate, and prolonged intensive care unit stay were not significantly different between the two groups. Kaplan-Meier analysis showed that there was no significant difference in lengths of hospital stay between the two groups (log-rank test, P > 0.999). CONCLUSION: In our cohort, there was no incidence of pneumothorax following robotic prostatectomy in patients with preoperative bullae. This result could help in the management of patients with prostate cancer with bullae.
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Neumotórax , Neoplasias de la Próstata , Procedimientos Quirúrgicos Robotizados , Masculino , Humanos , Neumotórax/epidemiología , Neumotórax/etiología , Vesícula/etiología , Vesícula/complicaciones , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados/efectos adversos , Prostatectomía/efectos adversos , Neoplasias de la Próstata/complicaciones , Neoplasias de la Próstata/cirugíaRESUMEN
Purpose: The aim is to evaluate the effect of amniotic membrane transplantation (AMT) on trabeculectomy with mitomycin C in patients with pseudoexfoliation glaucoma (PXG). Methods: This retrospective cohort study included 85 eyes of PXG who underwent trabeculectomy with or without AMT (52/33 eyes in the AMT/control group). Surgical success was defined by these criteria: (1) intraocular pressure (IOP) ≤18 mmHg and IOP reduction ≥20% and (2) IOP ≤15 mmHg and IOP reduction ≥25%. Criteria A and B defined complete success rates as patients who met these criteria without medication, respectively. Criteria C and D defined qualified success rates as patients who met these criteria with medication, respectively. Cumulative probabilities of success were compared using the Kaplan-Meier survival analysis. Cox proportional hazard models were used to evaluate the influence of AMT on surgical success accounting for confounding variables. Results: For the AMT group, compared with the control group, the complete success rates at 12 months for criterion A were 86.5% and 63.6%, respectively (P = 0.017) and for criterion B, 86.4% and 63.6% (P = 0.005). The qualified success rates at 12 months for criterion C were 92.1% and 75.1%, respectively (P = 0.047) and for criterion D, 92.1% and 72.1% (P = 0.021). On multivariable Cox regression analyses, AMT was associated with a lower failure rate on criteria A, B, and D (all P ≤ 0.047). Incidence of avascular bleb was higher in the control group than in the AMT group (7 vs 0 eyes; P = 0.004). Conclusions: In patients with PXG, trabeculectomy with AMT was associated with higher success rates and a lower incidence of avascular bleb compared with conventional trabeculectomy. Research Registration. This retrospective cohort study was registered at the Clinical Trial Registry of Korea (https://cris.nih.go.kr/cris/index/index.do, KCT0007228).
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In many filamentous red algae, cells that die from physical damage are replaced through somatic fusion of repair cells formed from adjacent cells. We visualized ROS generation in repair cells of Giriffthsia monilis using DCFH-DA staining and examined the expression of the genes involved in wound healing using quantitative PCR. Repair cells elongate along the H2O2 gradient, meet at each other's tips where the H2O2 concentration is highest, and undergo somatic fusion. No wound response occurred with ascorbic acid treatment. Conversely, H2O2 treatment induced many repair cells, leading to multiple somatic cell fusions. Diphenylene iodonium (DPI) or caffeine treatment reversibly inhibited ROS production in repair cells and blocked the progression of the wound response suggesting that ROS and calcium signaling are involved in the process. Four G. monilis homologues of NADPH-oxidase (GmRBOHs) were identified. The expression of GmRBOHs was upregulated upon injury, peaking 1 h post injury, and decreasing to initial levels when repair cells began to elongate. Our results suggest that ROS generated upon cell injury activates Ca2+ channels and upregulates the expression of GmRBOHs, and that H2O2 generated from repair cells mediates induced repair cell elongation leading to somatic cell fusion and filament repair.
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Peróxido de Hidrógeno , Rhodophyta , Señalización del Calcio , Fusión Celular , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/farmacología , Especies Reactivas de Oxígeno/metabolismo , Rhodophyta/metabolismoRESUMEN
Sulphur-selective conjugate addition reactions play a central role in synthetic chemistry and chemical biology. A general tool for conjugate addition reactions should provide high selectivity in the presence of competing nucleophilic functional groups, namely nitrogen nucleophiles. We report CO2-mediated chemoselective S-Michael addition reactions where CO2 can reversibly control the reaction pHs, thus providing practical reaction conditions. The increased chemoselectivity for sulphur-alkylation products was ascribed to CO2 as a temporary and traceless protecting group for nitrogen nucleophiles, while CO2 efficiently provide higher conversion and selectivity sulphur nucleophiles on peptides and human serum albumin (HSA) with various electrophiles. This method offers simple reaction conditions for cysteine modification reactions when high chemoselectivity is required.