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1.
Proc Natl Acad Sci U S A ; 120(34): e2221228120, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37590415

RESUMEN

Developing green heterogeneous catalysts with excellent Fenton-like activity is critical for water remediation technologies. However, current catalysts often rely on toxic transitional metals, and their catalytic performance is far from satisfactory as alternatives of homogeneous Fenton-like catalysts. In this study, a green catalyst based on Zn single-atom was prepared in an ammonium atmosphere using ZIF-8 as a precursor. Multiple characterization analyses provided evidence that abundant intrinsic defects due to the edge sites were created, leading to the formation of a thermally stable edge-hosted Zn-N4 single-atom catalyst (ZnN4-Edge). Density functional theory calculations revealed that the edge sites equipped the single-atom Zn with a super catalytic performance, which not only promoted decomposition of peroxide molecule (HSO5-) but also greatly lowered the activation barrier for •OH generation. Consequently, the as-prepared ZnN4-Edge exhibited extremely high Fenton-like performance in oxidation and mineralization of phenol as a representative organic contaminant in a wide range of pH, realizing its quick detoxification. The atom-utilization efficiency of the ZnN4-Edge was ~104 higher than an equivalent amount of the control sample without edge sites (ZnN4), and the turnover frequency was ~103 times of the typical benchmark of homogeneous catalyst (Co2+). This study opens up a revolutionary way to rationally design and optimize heterogeneous catalysts to homogeneous catalytic performance for Fenton-like application.

2.
J Virol ; 98(5): e0011624, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38591880

RESUMEN

Flaviviruses in the Japanese encephalitis virus (JEV) serogroup, such as JEV, West Nile virus, and St. Louis encephalitis virus, can cause severe neurological diseases. The nonstructural protein 1 (NS1) is a multifunctional protein of flavivirus that can be secreted by infected cells and circulate in the host bloodstream. NS1' is an additional form of NS1 protein with 52 amino acids extension at its carboxy-terminal and is produced exclusively by flaviviruses in the JEV serogroup. In this study, we demonstrated that the secreted form of both NS1 and NS1' can disrupt the blood-brain barrier (BBB) of mice, with NS1' exhibiting a stronger effect. Using the in vitro BBB model, we found that treatment of soluble recombinant JEV NS1 or NS1' protein increases the permeability of human brain microvascular endothelial cells (hBMECs) and leads to the degradation of tight junction proteins through the autophagy-lysosomal pathway. Consistently, NS1' protein exhibited a more pronounced effect compared to NS1 in these cellular processes. Further research revealed that the increased expression of macrophage migration inhibitory factor (MIF) is responsible for triggering autophagy after NS1 or NS1' treatment in hBMECs. In addition, TLR4 and NF-κB signaling was found to be involved in the activation of MIF transcription. Moreover, administering the MIF inhibitor has been shown to decrease viral loads and mitigate inflammation in the brains of mice infected with JEV. This research offers a novel perspective on the pathogenesis of JEV. In addition, the stronger effect of NS1' on disrupting the BBB compared to NS1 enhances our understanding of the mechanism by which flaviviruses in the JEV serogroup exhibit neurotropism.IMPORTANCEJapanese encephalitis (JE) is a significant viral encephalitis worldwide, caused by the JE virus (JEV). In some patients, the virus cannot be cleared in time, leading to the breach of the blood-brain barrier (BBB) and invasion of the central nervous system. This invasion may result in cognitive impairment, behavioral disturbances, and even death in both humans and animals. However, the mechanism by which JEV crosses the BBB remains unclear. Previous studies have shown that the flavivirus NS1 protein plays an important role in causing endothelial dysfunction. The NS1' protein is an elongated form of NS1 protein that is particularly produced by flaviviruses in the JEV serogroup. This study revealed that both the secreted NS1 and NS1' of JEV can disrupt the BBB by breaking down tight junction proteins through the autophagy-lysosomal pathway, and NS1' is found to have a stronger effect compared to NS1 in this process. In addition, JEV NS1 and NS1' can stimulate the expression of MIF, which triggers autophagy via the ERK signaling pathway, leading to damage to BBB. Our findings reveal a new function of JEV NS1 and NS1' in the disruption of BBB, thereby providing the potential therapeutic target for JE.


Asunto(s)
Autofagia , Barrera Hematoencefálica , Virus de la Encefalitis Japonesa (Especie) , Encefalitis Japonesa , Proteínas no Estructurales Virales , Animales , Humanos , Ratones , Barrera Hematoencefálica/virología , Barrera Hematoencefálica/metabolismo , Encéfalo/virología , Encéfalo/metabolismo , Virus de la Encefalitis Japonesa (Especie)/fisiología , Encefalitis Japonesa/virología , Encefalitis Japonesa/metabolismo , Células Endoteliales/virología , Células Endoteliales/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , FN-kappa B/metabolismo , Proteínas no Estructurales Virales/metabolismo
3.
Opt Lett ; 49(13): 3584-3587, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38950215

RESUMEN

Non-line-of-sight (NLOS) sensing is an emerging technique that is capable of detecting objects hidden behind a wall, around corners, or behind other obstacles. However, NLOS tracking of moving objects is challenging due to signal redundancy and background interference. Here, we demonstrate computational neuromorphic imaging with an event camera for NLOS tracking, unaffected by the relay surface, which can efficiently obtain non-redundant information. We show how this sensor, which responds to changes in luminance within dynamic speckle fields, allows us to capture the most relevant events for direct motion estimation. The experimental results confirm that our method has superior performance in terms of efficiency, and accuracy, which greatly benefits from focusing on well-defined NLOS object tracking.

4.
J Biochem Mol Toxicol ; 38(2): e23646, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38345168

RESUMEN

Circular RNAs (circRNAs) exhibit essential regulation in the malignant development of hepatocellular carcinoma (HCC). This study aims to investigate the physiological mechanisms of circ_0029343 encoded by scavenger receptor class B member 1 (SCARB1) involved in the growth and metastasis of HCC. Differentially expressed mRNAs in HCC were obtained, followed by the prediction of target genes of differentially expressed miRNAs and gene ontology and kyoto encyclopedia of genes and genomes analysis on the differentially expressed mRNAs. Moreover, the regulatory relationship between circRNAs encoded by SCARB1 and differentially expressed miRNAs was predicted. In vitro cell experiments were performed to verify the effects of circ_0029343, miR-486-5p, and SRSF3 on the malignant features of HCC cells using the gain- or loss-of-function experiments. Finally, the effects of circ_0029343 on the growth and metastasis of HCC cells in xenograft mouse models were also explored. It was found that miR-486-5p might interact with seven circRNAs encoded by SCARB1, and its possible downstream target gene was SRSF3. Moreover, SRSF3 was associated with the splicing of various RNA. circ_0029343 could sponge miR-486-5p to up-regulate SRSF3 and activate PDGF-PDGFRB (platelet-derived growth factor and its receptor, receptor beta) signaling pathway by inducing p73 splicing, thus promoting the proliferation, migration, and invasion and inhibiting apoptosis of HCC cells. In vivo, animal experiments further confirmed that overexpression of circ_0029343 could promote the growth and metastasis of HCC cells in nude mice. circ_0029343 encoded by SCARB1 may induce p73 splicing and activate the PDGF-PDGFRB signaling pathway through the miR-486-5p/SRSF3 axis, thus promoting the growth and metastasis of HCC cells.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Humanos , Animales , Ratones , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , ARN Circular/genética , ARN Circular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Ratones Desnudos , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , MicroARNs/genética , MicroARNs/metabolismo , Regulación Neoplásica de la Expresión Génica , Receptores Depuradores de Clase B/genética , Receptores Depuradores de Clase B/metabolismo , Factores de Empalme Serina-Arginina/genética , Factores de Empalme Serina-Arginina/metabolismo
5.
BMC Pulm Med ; 24(1): 252, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783268

RESUMEN

BACKGROUND: Conventional Mechanical ventilation modes used for individuals suffering from acute respiratory distress syndrome have the potential to exacerbate lung injury through regional alveolar overinflation and/or repetitive alveolar collapse with shearing, known as atelectrauma. Animal studies have demonstrated that airway pressure release ventilation (APRV) offers distinct advantages over conventional mechanical ventilation modes. However, the methodologies for implementing APRV vary widely, and the findings from clinical studies remain controversial. This study (APRVplus trial), aims to assess the impact of an early pathophysiology-driven APRV ventilation approach compared to a low tidal volume ventilation (LTV) strategy on the prognosis of patients with moderate to severe ARDS. METHODS: The APRVplus trial is a prospective, multicenter, randomized clinical trial, building upon our prior single-center study, to enroll 840 patients from at least 35 hospitals in China. This investigation plans to compare the early pathophysiology-driven APRV ventilation approach with the control intervention of LTV lung-protective ventilation. The primary outcome measure will be all-cause mortality at 28 days after randomization in the intensive care units (ICU). Secondary outcome measures will include assessments of oxygenation, and physiology parameters at baseline, as well as on days 1, 2, and 3. Additionally, clinical outcomes such as ventilator-free days at 28 days, duration of ICU and hospital stay, ICU and hospital mortality, and the occurrence of adverse events will be evaluated. TRIAL ETHICS AND DISSEMINATION: The research project has obtained approval from the Ethics Committee of West China Hospital of Sichuan University (2019-337). Informed consent is required. The results will be submitted for publication in a peer-reviewed journal and presented at one or more scientific conferences. TRIAL REGISTRATION: The study was registered at Clinical Trials.gov (NCT03549910) on June 8, 2018.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua , Respiración Artificial , Síndrome de Dificultad Respiratoria , Volumen de Ventilación Pulmonar , Humanos , Síndrome de Dificultad Respiratoria/terapia , Síndrome de Dificultad Respiratoria/fisiopatología , Estudios Prospectivos , Presión de las Vías Aéreas Positiva Contínua/métodos , Respiración Artificial/métodos , Ensayos Clínicos Controlados Aleatorios como Asunto , Unidades de Cuidados Intensivos , China , Estudios Multicéntricos como Asunto
6.
Radiology ; 306(1): 207-217, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36040333

RESUMEN

Background Three-dimensional (3D) time-of-flight (TOF) MR angiography (MRA) at 7 T has been reported to have high image quality for visualizing small perforating vessels. However, B1 inhomogeneity and more physiologic considerations limit its applications. Angiography at 5 T may provide another choice for intracranial vascular imaging. Purpose To evaluate the image quality and cerebrovascular visualization of 5-T 3D TOF MRA for visualizing intracranial small branch arteries. Materials and Methods Participants (healthy volunteers or participants with a history of ischemic stroke undergoing intracranial CT angiography or MRA for identifying steno-occlusive disease) were prospectively included from September 2021 to November 2021. Each participant underwent 3-T, 5-T, and 7-T 3D TOF MRA with use of customized MR protocols within 48 hours. Radiologist scoring from 0 (invisible) to 3 (excellent) and quantitative assessment were obtained to evaluate the image quality. The Friedman test was used for comparison of characteristics derived from 3 T, 5 T, and 7 T. Results A total of 12 participants (mean age ± SD, 38 years ± 9; nine men) were included. Visualizations of the distal arteries and small vessels at 5-T TOF MRA were significantly higher than those at 3 T (median score: 3.0 vs 2.0, all P < .001 for distal segments and lenticulostriate artery; median score: 2.0 vs 0, P < .001 for pontine artery). The total length of small vessel branches detected at 5 T was larger than that at 3 T (5.1 m ± 0.7 vs 1.9 m ± 0.4; P < .001). However, there was no evidence of a significant difference compared with 7 T in either the depiction of distal segments and small vessel branches (average median score, 2.5; all P > .05) or the quantitative measurements (total length, 5.6 m ± 0.5; P = .41). Conclusion Three-dimensional time-of-flight MR angiography at 5 T presented the capability to provide superior visualization of distal large arteries and small vessel branches (in terms of subjective and quantitative assessment) to 3 T and had image quality similar to 7 T. © RSNA, 2022 Online supplemental material is available for this article. An earlier incorrect version appeared online. This article was corrected on September 14, 2022.


Asunto(s)
Angiografía por Resonancia Magnética , Tomografía Computarizada por Rayos X , Masculino , Humanos , Angiografía por Resonancia Magnética/métodos , Arterias Cerebrales , Arteria Cerebral Media , Angiografía por Tomografía Computarizada , Imagenología Tridimensional
7.
J Neuroinflammation ; 20(1): 168, 2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37480121

RESUMEN

Histone methylation is an important epigenetic modification that affects various biological processes, including the inflammatory response. In this study, we found that infection with Japanese encephalitis virus (JEV) leads to an increase in H3K27me3 in BV2 microglial cell line, primary mouse microglia and mouse brain. Inhibition of H3K27me3 modification through EZH2 knockdown and treatment with EZH2 inhibitor significantly reduces the production of pro-inflammatory cytokines during JEV infection, which suggests that H3K27me3 modification plays a crucial role in the neuroinflammatory response caused by JEV infection. The chromatin immunoprecipitation-sequencing (ChIP-sequencing) assay revealed an increase in H3K27me3 modification of E3 ubiquitin ligases Rnf19a following JEV infection, which leads to downregulation of Rnf19a expression. Furthermore, the results showed that Rnf19a negatively regulates the neuroinflammatory response induced by JEV. This is achieved through the degradation of RIG-I by mediating its ubiquitination. In conclusion, our findings reveal a novel mechanism by which JEV triggers extensive neuroinflammation from an epigenetic perspective.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie) , Virus de la Encefalitis Japonesa (Subgrupo) , Encefalitis Japonesa , Animales , Ratones , Histonas , Encefalitis Japonesa/genética , Inflamación , Ubiquitina-Proteína Ligasas/genética
8.
J Transl Med ; 21(1): 752, 2023 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-37880710

RESUMEN

BACKGROUND: Long non-coding RNA (lncRNA) HOTAIR acts importantly in liver cancer development, but its effect on radioresistance remains poorly understood. Here, our study probed into the possible impact of HOTAIR in radioresistance in liver cancer stem cells (LCSCs) and to elucidate its molecular basis. METHODS: Following sorting of stem and non-stem liver cancer cells, LCSCs were identified and subjected to RNA-seq analysis for selecting differentially expressed genes. Expression of HOTAIR was determined in liver cancer tissues and CSCs. The stemness, proliferation, apoptosis and radioresistance of LCSCs were then detected in response to altered expression of HOTAIR-LSD1-JMJD6-BRD4. RESULTS: Ectopic HOTAIR expression was found to promote radioresistance of LCSCs by maintaining its stemness. Mechanistic investigations indicated that HOTAIR recruited LSD1 to the MAPK1 promoter region and reduced the level of H3K9me2 in the promoter region, thus elevating ERK2 (MAPK1) expression. JMJD6-BRD4 complex promoted HOTAIR transcription by forming a complex and positively regulated ERK2 (MAPK1) expression, maintaining the stemness of LCSCs, and ultimately promoting their radioresistance in vitro and in vivo. CONCLUSION: Collectively, our work highlights the promoting effect of the JMJD6-BRD4 complex on the radioresistance of LCSCs through a HOTAIR-dependent mechanism.


Asunto(s)
Neoplasias Hepáticas , ARN Largo no Codificante , Humanos , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Histona Demetilasas/genética , Histona Demetilasas/metabolismo , Histona Demetilasas con Dominio de Jumonji/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/metabolismo , Células Madre Neoplásicas/metabolismo , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Factores de Transcripción/metabolismo
9.
Opt Express ; 31(12): 19588-19603, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37381370

RESUMEN

Optical imaging through scattering media is a practical challenge with crucial applications in many fields. Many computational imaging methods have been designed for object reconstruction through opaque scattering layers, and remarkable recovery results have been demonstrated in the physical models or learning models. However, most of the imaging approaches are dependent on relatively ideal states with a sufficient number of speckle grains and adequate data volume. Here, the in-depth information with limited speckle grains has been unearthed with speckle reassignment and a bootstrapped imaging method is proposed for reconstruction in complex scattering states. Benefiting from the bootstrap priors-informed data augmentation strategy with a limited training dataset, the validity of the physics-aware learning method has been demonstrated and the high-fidelity reconstruction results through unknown diffusers are obtained. This bootstrapped imaging method with limited speckle grains broadens the way to highly scalable imaging in complex scattering scenes and gives a heuristic reference to practical imaging problems.

10.
Opt Express ; 31(22): 36503-36520, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38017801

RESUMEN

Effectively imaging through dynamic scattering media is of great importance and challenge. Some imaging methods based on physical or learning models have been designed for object reconstruction. However, with an increase in exposure time or more drastic changes in the scattering medium, the speckle pattern superimposed during camera integration time undergoes more significant changes, resulting in a modification of the collected speckle structure and increased blurring, which brings significant challenges to the reconstruction. Here, the clearer structural information of blurred speckles is unearthed with a presented speckle de-blurring algorithm, and a high-throughput imaging method through rapidly changing scattering media is proposed for reconstruction under long exposure. For the problem of varying blur degrees in different regions of the speckle, a block-based method is proposed to divide the speckle into distinct sub-speckles, which can realize the reconstruction of hidden objects. The imaging of hidden objects with different complexity through dynamic scattering media is demonstrated, and the reconstruction results are improved significantly for speckles with different blur degrees, which verifies the effectiveness of the method. This method is a high-throughput approach that enables non-invasive imaging solely through the collection of a single speckle. It directly operates on blurred speckles, making it suitable for traditional speckle-correlation methods and deep learning (DL) methods. This provides a new way of thinking about solving practical scattering imaging challenges.

11.
J Magn Reson Imaging ; 56(4): 1009-1017, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35119776

RESUMEN

BACKGROUND: Recently, a prototype 5.0 T whole-body MRI scanner was developed. A 5.0 T diffusion-weighted imaging (DWI) may help overcome the issues that limit 3.0 T DWI. PURPOSE: To evaluate the feasibility of 5.0 T high-field DWI in the upper abdomen and assess the agreement of the apparent diffusion coefficient (ADC) with that from 3.0 T abdominal DWI. STUDY TYPE: Prospective proof of concept. POPULATION: Nine volunteers (mean ± SD age: 37.3 ± 7.0 years, 8 M), eight healthy and one with liver and kidney cysts. FIELD STRENGTH/SEQUENCE: 3.0 T and 5.0 T; respiratory-triggered spin-echo echo-planar-imaging (SE-EPI)-based DWI sequence. ASSESSMENT: Subjective image quality scores. The ADC values in abdominal organs (liver, pancreas, spleen, and kidney) were measured by two observers for evaluating the interobserver and interfield agreement. STATISTICAL TESTS: Wilcoxon-rank sum test, Bland-Altman analysis, intraclass correlation coefficients (ICCs), and coefficients of variation (CVs). RESULTS: The 5.0 T DWI displayed an increase in subjective image quality score compared to 3.0 T DWI without the significant difference (3.0 T DWI: 3.50 ± 0.47, 5.0 T DWI: 3.72 ± 0.42, P = 0.157). Both the interfield and interobserver agreements of ADC values were substantial to excellent (ICCs = 0.640-0.902). For all four upper abdominal organs, there were no significant differences between the ADC values measured by two observers and between the ADC values of 3.0 T and 5.0 T DWI (P = 0.134-1.000). The CVs of ADC measurements from 3.0 T and 5.0 T DWI were all less than 15.0% (6.7%-14.2%). DATA CONCLUSION: The substantial to excellent agreements between the ADC values measured with 3.0 T and 5.0 T DWI for liver, pancreas, spleen, and kidney suggested that 5.0 T DWI can be applied for abdominal imaging. The ADC values from 5.0 T abdominal DWI hold the potential to serve as the quantitative markers for clinical investigations. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Imagen Eco-Planar , Abdomen/diagnóstico por imagen , Adulto , Imagen de Difusión por Resonancia Magnética/métodos , Imagen Eco-Planar/métodos , Humanos , Imagen por Resonancia Magnética , Estudios Prospectivos , Reproducibilidad de los Resultados
12.
Eur Radiol ; 32(6): 4198-4209, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35079885

RESUMEN

OBJECTIVES: To explore the importance of three-dimensional (3D) quantitative analysis during gadoxetic acid-enhanced magnetic resonance imaging (MRI) of microvascular invasion (MVI) and early recurrence (< 2 years) after surgery of single hepatocellular carcinoma (HCC) ≤ 3 cm. METHODS: Two hundred fourteen patients with pathologically confirmed HCC (training cohort: n = 169; validation cohort: n = 45) were included retrospectively. The 3D quantitative parameters (volume, sphericity, and compacity) and conventional MRI features were analyzed. The significant predictors for MVI were identified using univariate and multivariate logistic regression analyses. Nomograms were constructed from the prediction model, and the relationship between the significant predictors and early recurrence rates was evaluated using the Kaplan-Meier method. RESULTS: Tumor sphericity (odds ratio [OR] = 0.000; p < 0.001), non-smooth tumor margin (OR = 3.353; p = 0.015), and peritumoral hypointensity on hepatobiliary phase (HBP) (OR = 14.067; p = 0.003) were independent significant factors for MVI. When these three factors were combined, the diagnostic specificity of the training and validation cohorts was 97.0 (128/132) and 87.9 (29/33), respectively. The nomogram based on the predictive model performed satisfactorily in the training (C-index: 0.885) and validation (C-index: 0.869) cohorts. Early recurrence rates of patients with two or three significant factors were significantly higher than those with none in the training (29.1% vs. 10.2%, p = 0.007) and validation (36.4% vs. 6.7%, p = 0.037) cohorts. CONCLUSIONS: Lower sphericity combined with non-smooth tumor margin and peritumoral hypointensity on HBP are potential predictive factors for MVI and associated with early recurrence after surgery of HCC ≤ 3 cm. KEY POINTS: • Lower sphericity, non-smooth tumor margin, and peritumoral hypointensity on HBP were important indicators of the occurrence of MVI in HCC. • The combinational model prepared from these findings satisfactorily predicted MVI, and the presence of these predictors was associated with an early recurrence rate after surgical resection in HCC patients. • This model could help clinicians in the preoperative management of small HCC ≤ 3 cm.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética/métodos , Invasividad Neoplásica/patología , Estudios Retrospectivos
13.
Appl Opt ; 61(35): 10352-10361, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-36607093

RESUMEN

In complex imaging settings, optical scattering often prohibits the formation of a clear target image, and instead, only a speckle without the original spatial structure information is obtained. Scattering seriously interferes with the locating of targets; especially, when the scattering medium is dynamic, the dynamic nature leads to rapid decorrelation of optical information in time, and the challenge increases. Here, a locating method is proposed to detect the target hidden behind a dynamic scattering medium, which uses the a priori information of a known reference object in the neighborhood of the target. The research further designs an automatic calibration method to simplify the locating process, and analyzes the factors affecting positioning accuracy. The proposed method enables us to predict the position of a target from the autocorrelation of the captured speckle pattern; the angle and distance deviations of the target are all within 2.5%. This approach can locate a target using only a single-shot speckle pattern, and it is beneficial for target localization in dynamic scattering conditions.

14.
Acta Radiol ; 63(6): 734-742, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33969700

RESUMEN

BACKGROUND: Gadoxetic acid-enhanced magnetic resonance imaging (MRI) has been widely used in clinical practice. However, scientific evidence is lacking for recommending a particular sequence for measuring tumor size. PURPOSE: To retrospectively compare the size of hepatocellular carcinoma (HCC) measured on different gadoxetic acid-enhanced MRI sequences using pathology as a reference. MATERIAL AND METHODS: A total of 217 patients with single HCC who underwent gadoxetic acid-enhanced MRI before surgery were included. The size of the HCC was measured by two abdominal radiologists independently on the following sequences: T1-weighted; T2-weighted; b-500 diffusion-weighted imaging (DWI); and arterial, portal venous, transitional, and hepatobiliary phases. Tumor size measured on MRI was compared with pathological size by using Pearson correlation coefficient, independent-sample t test, and Bland-Altman plot. Agreement between two readers was evaluated with intraclass correlation coefficient (ICC). RESULTS: Correlation between the MR images and pathology was high for both readers (0.899-0.955). Absolute error between MRI and pathologic assessment was lowest on hepatobiliary phase images for both readers (reader 1, 2.8±4.2 mm; reader 2, 3.2±3.4 mm) and highest on arterial phase images for reader 1 (4.9±4.4 mm) and DWI phase images for reader 2 (5.1±4.9 mm). Absolute errors were significantly different for hepatobiliary phase compared with other sequences for both readers (reader 1, P≤0.012; reader 2, P≤0.037). Inter-reader agreements for all sequence measurements were strong (0.971-0.997). CONCLUSION: The performance of gadoxetic acid-enhanced MRI sequences varied with HCC size, and the hepatobiliary phase may be optimal among these sequences.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Medios de Contraste , Gadolinio DTPA , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Imagen por Resonancia Magnética/métodos , Estudios Retrospectivos , Sensibilidad y Especificidad
15.
Opt Express ; 29(24): 40024-40037, 2021 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-34809353

RESUMEN

Color imaging with scattered light is crucial to many practical applications and becomes one of the focuses in optical imaging fields. More physics theories have been introduced in the deep learning (DL) approach for the optical tasks and improve the imaging capability a lot. Here, an efficient color imaging method is proposed in reconstructing complex objects hidden behind unknown opaque scattering layers, which can obtain high reconstruction fidelity in spatial structure and accurate restoration in color information by training with only one diffuser. More information is excavated by utilizing the scattering redundancy and promotes the physics-aware DL approach to reconstruct the color objects hidden behind unknown opaque scattering layers with robust generalization capability by an efficient means. This approach gives impetus to color imaging through dynamic scattering media and provides an enlightening reference for solving complex inverse problems based on physics-aware DL methods.

16.
Liver Transpl ; 26(6): 751-763, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31901208

RESUMEN

Small recurrent hepatocellular carcinoma (HCC) can show atypical imaging patterns, and a specific diagnostic algorithm for HCC is lacking. This study aimed to better characterize postoperative recurrent HCCs <20 mm in size with gadoxetic acid-enhanced magnetic resonance imaging (MRI). We evaluated 373 newly developed nodules after hepatectomy in 204 HCC patients with chronic hepatitis B virus infection. The diagnostic performance of Liver Imaging Reporting and Data System (LI-RADS) version 2018 was calculated with gadoxetic acid-enhanced MRI to characterize recurrent HCC. Modified diagnostic algorithms were proposed by combining significant imaging biomarkers related to subcentimeter and 10-19 mm recurrence, and the algorithms were then compared with the LI-RADS system. A total of 256 recurrent HCCs (108 recurrent HCCs <10 mm in size; 148 recurrent HCCs 10-19 mm in size) were confirmed via histology or follow-up imaging. Nonrim arterial phase hyperenhancement (APHE) and 3 LI-RADS ancillary features (AFs; hepatobiliary phase hypointensity, mild-moderate T2 hyperintensity, and restricted diffusion) were significantly related to recurrent HCCs <20 mm in size according to a multivariate analysis. For subcentimeter recurrence, combining at least 2 of the 3 AFs only achieved better specificity (sensitivity, 83.3%; specificity, 87.7%) than the LR-4 category (sensitivity, 88.9%, P = 0.21; specificity, 70.8%, P = 0.006). For 10-19 mm recurrences, combining nonrim APHE and at least 1 of the 3 AFs achieved only a significantly enhanced sensitivity of 85.1% but a lower specificity of 86.5% compared with the LR-5 category (sensitivity: 63.5%, P < 0.001; specificity: 94.2%, P = 0.13). In conclusion, the diagnostic algorithms for subcentimeter and 10-19 mm recurrent HCCs should be stratified. Combining at least 2 AFs demonstrated comparable sensitivity with significantly enhanced specificity compared with the LR-4 category for characterizing subcentimeter recurrence.


Asunto(s)
Carcinoma Hepatocelular , Hepatitis B Crónica , Neoplasias Hepáticas , Trasplante de Hígado , Algoritmos , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/cirugía , Medios de Contraste , Gadolinio DTPA , Virus de la Hepatitis B , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/diagnóstico por imagen , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Imagen por Resonancia Magnética , Recurrencia Local de Neoplasia/diagnóstico por imagen , Estudios Retrospectivos , Sensibilidad y Especificidad
17.
Opt Express ; 28(2): 2433-2446, 2020 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-32121933

RESUMEN

Strong scattering medium brings great difficulties to image objects. Optical memory effect makes it possible to image through strong random scattering medium in a limited angle field-of-view (FOV). The limitation of FOV results in a limited optical memory effect range, which prevents the optical memory effect to be applied to real imaging applications. In this paper, a kind of practical convolutional neural network called PDSNet (Pragmatic De-scatter ConvNet) is constructed to image objects hidden behind different scattering media. The proposed method can expand at least 40 times of the optical memory effect range with a average PSNR above 24dB, and enable to image complex objects in real time, even for objects with untrained scales. The provided experiments can verify its accurateness and efficiency.

18.
Sensors (Basel) ; 21(1)2020 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-33375637

RESUMEN

Scattering medium brings great difficulties to locate and reconstruct objects especially when the objects are distributed in different positions. In this paper, a novel physics and learning-heuristic method is presented to locate and image the object through a strong scattering medium. A novel physics-informed framework, named DINet, is constructed to predict the depth and the image of the hidden object from the captured speckle pattern. With the phase-space constraint and the efficient network structure, the proposed method enables to locate the object with a depth mean error less than 0.05 mm, and image the object with an average peak signal-to-noise ratio (PSNR) above 24 dB, ranging from 350 mm to 1150 mm. The constructed DINet firstly solves the problem of quantitative locating and imaging via a single speckle pattern in a large depth. Comparing with the traditional methods, it paves the way to the practical applications requiring multi-physics through scattering media.

19.
BMC Med Imaging ; 19(1): 43, 2019 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-31126251

RESUMEN

BACKGROUND: The purpose was to investigate the difference of detection rate of incidental pancreatic cystic lesions (PCLs) with computed tomography (CT) and magnetic resonance imaging (MRI) and to compare the difference between CT and MRI and to explore the effect of this difference on surgical resection. METHODS: We reviewed the diagnostic reports for incidental PCLs between 2013 and 2016. Images of PCLs would be re-evaluated. Clinical and imaging data were recorded. The chi-square and independent t-test were conducted for categorical and continuous variables. RESULTS: The prevalence of PCLs was 1.91% (1038/54210) and 3.36% (1282/38099) on CT and MRI respectively, and increased with increasing age (P < 0.001). No significant differences were found in the annual prevalence of PCLs on CT (P = 0.796) and MRI (P = 0.213) from 2013 to 2016 while the number of examinations was increasing every year. The annual detection rate of MRI for small PCLs (< 20 mm) was significantly higher than CT (P < 0.001), but was not significantly different for large PCLs (≥20 mm). The rate of surgical resection of PCLs (≥20 mm) in MRI group was higher than CT (55.2% vs. 37.0%, P < 0.001). CONCLUSIONS: The detection rate of PCLs on CT and MRI tended to be stable despite increasing scan volumes. Female had a slightly more frequency of PCLs than male. MRI detected more small PCLs(< 20 mm) and had higher impact on surgical resection of large PCL(≥20 mm) compared with CT.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Quiste Pancreático/diagnóstico por imagen , Quiste Pancreático/cirugía , Tomografía Computarizada por Rayos X/métodos , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , China , Femenino , Humanos , Hallazgos Incidentales , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Sensibilidad y Especificidad , Factores Sexuales , Adulto Joven
20.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(2): 273-279, 2018 04 25.
Artículo en Zh | MEDLINE | ID: mdl-29745534

RESUMEN

The use of echocardiography ventricle segmentation can obtain ventricular volume parameters, and it is helpful to evaluate cardiac function. However, the ultrasound images have the characteristics of high noise and difficulty in segmentation, bringing huge workload to segment the object region manually. Meanwhile, the automatic segmentation technology cannot guarantee the segmentation accuracy. In order to solve this problem, a novel algorithm framework is proposed to segment the ventricle. Firstly, faster region-based convolutional neural network is used to locate the object to get the region of interest. Secondly, K-means is used to pre-segment the image; then a mean shift with adaptive bandwidth of kernel function is proposed to segment the region of interest. Finally, the region growing algorithm is used to get the object region. By this framework, ventricle is obtained automatically without manual localization. Experiments prove that this framework can segment the object accurately, and the algorithm of adaptive mean shift is more stable and accurate than the mean shift with fixed bandwidth on quantitative evaluation. These results show that the method in this paper is helpful for automatic segmentation of left ventricle in echocardiography.

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