Ischemia is a significant factor affecting the repair of peripheral nerve injuries,while exosomes have been shown to promote angiogenesis.To further investigate the detailed processes and efficacy of exosome thera⁃py ...Ischemia is a significant factor affecting the repair of peripheral nerve injuries,while exosomes have been shown to promote angiogenesis.To further investigate the detailed processes and efficacy of exosome thera⁃py for ischemic peripheral nerve injuries,this study utilized glucose-modified near-infrared-II(NIR-II)quantum dots(QDs)to label adipose-derived stem cell exosomes(QDs-ADSC-Exos),enabling long-term in vivo NIR-II imaging of exosome treatment for ischemic peripheral nerve damage.Experimental results confirmed that QDs can be used for non-invasive in vitro labeling of exosomes,with QDs-ADSC-Exos exhibiting strong fluorescence signals in the NIR-II window and demonstrating favorable NIR-II imaging characteristics in vivo.Notably,QDsADSC-Exos showed accumulation at the site of nerve injury in cases of ischemic peripheral nerve damage.Func⁃tional neurological assessments indicated that QDs-ADSC-Exos effectively promoted neural regeneration.This study highlights the potential of exosomes in treating ischemic peripheral nerve injuries and elucidates the spatio⁃temporal characteristics of exosome therapy,providing objective evidence for the further optimization of exosomebased treatment protocols.展开更多
Laser wakefield accelerators(LWFAs)offer acceleration gradients up to 1000 times higher than those of conventional radio-frequency accelerators,offering a pathway to significantly more compact and cost-effective accel...Laser wakefield accelerators(LWFAs)offer acceleration gradients up to 1000 times higher than those of conventional radio-frequency accelerators,offering a pathway to significantly more compact and cost-effective accelerator systems.This breakthrough opens up new possibilities for laboratory-scale light sources.All-optical inverse Compton scattering(AOCS)sources driven by LWFAs produce high-brightness,quasimonochromatic X rays with micrometer-scale source sizes,delivering the spatial coherence and resolution required for X-ray phase-contrast imaging(XPCI).These features position AOCS X-ray sources as promising tools for applications in biology,medicine,physics,and materials science.However,previous AOCS-based imaging studies have primarily focused on X-ray absorption imaging.In this work,we report successful experimental demonstrations of edge-enhanced in-line XPCI using energy-tunable,quasi-monochromatic AOCS X rays.With a spatial resolution of~20μm,our results clearly show the potential of high-resolution,AOCS-based XPCI applications.展开更多
Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indice...Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indices,has provided a fresh perspective and valuable insight into the study of freezing of gait in Parkinson's disease.It has been revealed that Parkinson's disease is accompanied by widespread irregularities in inherent brain network activity.However,the effective integration of the multi-level indices of resting-state functional magnetic resonance imaging into clinical settings for the diagnosis of freezing of gait in Parkinson's disease remains a challenge.Although previous studies have demonstrated that radiomics can extract optimal features as biomarkers to identify or predict diseases,a knowledge gap still exists in the field of freezing of gait in Parkinson's disease.This cross-sectional study aimed to evaluate the ability of radiomics features based on multi-level indices of resting-state functional magnetic resonance imaging,along with clinical features,to distinguish between Parkinson's disease patients with and without freezing of gait.We recruited 28 patients with Parkinson's disease who had freezing of gait(15 men and 13 women,average age 63 years)and 30 patients with Parkinson's disease who had no freezing of gait(16 men and 14 women,average age 64 years).Magnetic resonance imaging scans were obtained using a 3.0T scanner to extract the mean amplitude of low-frequency fluctuations,mean regional homogeneity,and degree centrality.Neurological and clinical characteristics were also evaluated.We used the least absolute shrinkage and selection operator algorithm to extract features and established feedforward neural network models based solely on resting-state functional magnetic resonance imaging indicators.We then performed predictive analysis of three distinct groups based on resting-state functional magnetic resonance imaging indicators indicators combined with clinical features.Subsequently,we conducted 100 additional five-fold cross-validations to determine the most effective model for each classification task and evaluated the performance of the model using the area under the receiver operating characteristic curve.The results showed that when differentiating patients with Parkinson's disease who had freezing of gait from those who did not have freezing of gait,or from healthy controls,the models using only the mean regional homogeneity values achieved the highest area under the receiver operating characteristic curve values of 0.750(with an accuracy of 70.9%)and 0.759(with an accuracy of 65.3%),respectively.When classifying patients with Parkinson's disease who had freezing of gait from those who had no freezing of gait,the model using the mean amplitude of low-frequency fluctuation values combined with two clinical features achieved the highest area under the receiver operating characteristic curve of 0.847(with an accuracy of 74.3%).The most significant features for patients with Parkinson's disease who had freezing of gait were amplitude of low-frequency fluctuation alterations in the left parahippocampal gyrus and two clinical characteristics:Montreal Cognitive Assessment and Hamilton Depression Scale scores.Our findings suggest that radiomics features derived from resting-state functional magnetic resonance imaging indices and clinical information can serve as valuable indices for the identification of freezing of gait in Parkinson's disease.展开更多
Metasurfaces are artificial structures that can finely control the characteristics of electromagnetic waves at subwavelength scales,and they are widely used to manipulate the propagation,phase,amplitude,and polariza⁃t...Metasurfaces are artificial structures that can finely control the characteristics of electromagnetic waves at subwavelength scales,and they are widely used to manipulate the propagation,phase,amplitude,and polariza⁃tion of light.In this work,a bound state in the continuum(BIC)structure based on a metallic metasurface is pro⁃posed.By adjusting the metallic structure using CST and COMSOL software,a significant quasi-BIC peak can be achieved at a frequency of 0.8217 terahertz(THz).Through multi-level expansion analysis,it is found that the electric dipole(ED)is the main factor contributing to the resonant characteristics of the structure.By leveraging the characteristics of BIC,an imaging system was created and operated.According to the simulation results,the imaging system demonstrated excellent sensitivity and resolution,revealing the great potential of terahertz imag⁃ing.This research not only provides new ideas for the creation of BIC structures but also offers an effective refer⁃ence for the development of high-performance terahertz imaging technology.展开更多
Raman imaging,as a molecular spectroscopy technique,has been widely studied and applied in research fields such as life sciences and food safety due to its excellent specificity and high resolution.However,its develop...Raman imaging,as a molecular spectroscopy technique,has been widely studied and applied in research fields such as life sciences and food safety due to its excellent specificity and high resolution.However,its development still faces challenges such as weak signals,slow acquisition speed,and insufficient penetration depth.In recent years,the rapid development of aggregate science has provided new insights for addressing these limitations.Aggregation-induced emission(AIE)materials exhibit enhanced signals in the aggregated state,which may compensate for the inherent weak Raman signals.This article reviews the cutting-edge progress of Raman imaging technology and its current status in cross-disciplinary research with aggregate science,emphasizing the strategy of constructing AIE-Raman dual-responsive probes through molecular engineering to achieve functional complementarity between fluorescence localization and Raman quantification,thereby significantly improving detection sensitivity and specificity.These probes have demonstrated single-cell resolution and high spatiotemporal accuracy in applications such as tumor surgical navigation,diagnosis and treatment of drug-resistant bacteria,and dynamic monitoring of organelles.We also analyze the bottlenecks in this field,such as biological safety and the complexity of molecular design,and outline the future development directions,including intelligent responsive probes,artificial intelligence-assisted analysis,and multimodal fusion platforms.The integration of Raman imaging and AIE sheds new light in the field of medical imaging.展开更多
Two novel aggregation-induced emission(AIE)-active probes,TPA-H and TPA-2 F,were designed and synthesized based on a triphenylamine(TPA)core.Systematic characterization demonstrated that both probes exhibit excellent ...Two novel aggregation-induced emission(AIE)-active probes,TPA-H and TPA-2 F,were designed and synthesized based on a triphenylamine(TPA)core.Systematic characterization demonstrated that both probes exhibit excellent biocompatibility(cell viability>90%at concentrations up to 50μmol/L)and outstanding LD-targeting speci⁃ficity with minimal colocalization with other organelles such as mitochondria and lysosomes.During early differentia⁃tion of 3 T 3-L 1 adipocytes,both TPA-2 F and TPA-H clearly visualized small and nascent LDs that were difficult to be detected with BODIPY,indicating superior imaging sensitivity compared to the existing fluorescent probes for LDs.Moreover,TPA-2 F demonstrated exceptional photostability,retaining over 90%of its initial fluorescence intensity after 100 continuous laser scanning cycles,significantly outperforming TPA-H.This work not only provides two high-performance LD imaging tools but also highlights the potential of AIE luminogens(AIEgens)in organelle-specific bioimaging,offering promising avenues for early diagnosis and mechanistic research of lipid-related metabolic diseases.展开更多
Medical imaging is essential in modern health care,allowing accurate diagnosis and effective treatment planning.These images,however,often demonstrate low contrast,noise,and brightness distortion that reduce their dia...Medical imaging is essential in modern health care,allowing accurate diagnosis and effective treatment planning.These images,however,often demonstrate low contrast,noise,and brightness distortion that reduce their diagnostic reliability.This review presents a structured and comprehensive analysis of advanced histogram equalization(HE)-based techniques for medical image enhancement.Our review methodology encompasses:(1)classical HE approaches and related limitations in medical domains;(2)adaptive schemes like Adaptive Histogram Equalization(AHE)and Contrast Limited Adaptive Histogrma Equalization(CLAHE)and their advance variants;(3)brightnesspreserving schemes like BBHE and MMBEBHE and related algorithms;(4)dynamic and recursive histogram equalization methods incorporating DHE and RMSHE;(5)fuzzy logic-based enhancement methodologies addressing uncertainty and noise in medical images;and(6)hybrid optimization methodologies through the application of metaheuristic algorithms(World Cup Optimization,Particle Swarm Optimization,Genetic Algorithms,along with histogram-based methodologies.)There is also a comparative discussion given based on contrast improvement,image brightness preservation,noise management,and computational efficiency.Such advancements have better capabilities of improving image quality,which is more important for improved diagnosis and image analysis.展开更多
Background:Sarcomatoid carcinoma of the ureter(SCU)is a highly aggressive and relatively uncommon malignant tumor of the urinary tract.Its frequency is quite low,and its prognosis is very bad when compared to other ca...Background:Sarcomatoid carcinoma of the ureter(SCU)is a highly aggressive and relatively uncommon malignant tumor of the urinary tract.Its frequency is quite low,and its prognosis is very bad when compared to other cancers of the urinary system.SCU clinical reports are still hard to come by.MRI and PEI/CT imaging of ureteral sarcomatoid cancer is presented in this case to promote diagnostic awareness and comprehension of the imaging characteristics of this uncommon illness.Method:The patient had ureteral sarcomatoid cancer,which was verified by pathological investigation after ureteroscopic biopsy.The patient’s clinical information,imaging results,surgical outcomes,and pathological findings were gathered.A retrospective study was carried out in combinationwith pertinent national and international literature.Results:An 84-year-old female patient was admitted for“left flank discomfort lasting over one month.”MRI revealed an irregular soft tissue mass in the middle-lower segment of the left ureter.T2-weighted imaging showed an unevenly slightly hyperintense signal.Diffusion-weighted imaging demonstrated restricted diffusion.Contrastenhanced imaging exhibited heterogeneous enhancement.PET/CT demonstrated significantly increased fluorodeoxyglucose metabolism in the mass with secondary left upper urinary tract obstruction.Concurrent findings included a solitary metastatic lesion in hepatic segment S6 and multiple lymph node metastases along the left common iliac and external iliac arteries.Preoperative diagnosis suggested a malignant tumor of the ureter.The patient underwent left nephroureteroscopy with biopsy,and the postoperative pathological diagnosis was ureteral sarcomatoid carcinoma.Conclusion:Ureteral sarcomatoid carcinoma is a rare,highly malignant,and aggressive tumor with nonspecific imaging features,typically presenting as an invasively growing mass.Diagnosis relies on postoperative pathology and immunohistochemical examination.MRI and PET/CT scans are valuable for preoperative localization and characterization,tumor staging,treatment planning,and postoperative follow-up.The prognosis is extremely negative.The main treatment option is radical surgery,although constant monitoring is necessary since early recurrence and metastases are frequent after surgery.展开更多
The level of glutathione(GSH)is significantly associated with numerous pathological processes,thus,real-time detection of the GSH level is of significance for early diagnosis of GSH-related diseases.Herein,we develope...The level of glutathione(GSH)is significantly associated with numerous pathological processes,thus,real-time detection of the GSH level is of significance for early diagnosis of GSH-related diseases.Herein,we developed in vivo second near-infrared(NIR-II)window fluorescence(FL)and ratiometric photoacoustic(RPA)dual-modality imaging of GSH using a GSH-activatable probe(LET-14).LET-14 was synthesized based on a rhodamine hybrid xanthene skeleton with a FL shielding 2,4-dinitrobenzene sulfonyl group that can be specifically cleaved by GSH,thus resulting in a markedly bathochromic-shift absorption,a 6.5-fold increase in NIR-II FL intensity(FL_(920))and a 13-fold increase in RPA signal(PA_(880)/PA_(705))in vitro.Intriguingly,LET-14 exhibits good selectivity and sensitivity for NIR-II FL and RPA dual-modality imaging of GSH in 4T1 tumor-bearing mouse model.Our findings develop an in vivo detection tool of GSH,which has great potential in the field of cancer diagnosis.展开更多
Neuromorphic cameras,or dynamic vision sensors,are bio-inspired event cameras that measure changes in the image brightness asynchronously and independently at the pixel level.Recently,they garnered increasing interest...Neuromorphic cameras,or dynamic vision sensors,are bio-inspired event cameras that measure changes in the image brightness asynchronously and independently at the pixel level.Recently,they garnered increasing interest due to their extremely high temporal resolution,wide dynamic range,low power consumption,and high pixel bandwidth.Despite their advantages,most existing three-dimensional (3D) event imaging solutions rely on multicamera configurations,which are costly,complex,and challenging to synchronize.In this study,we introduce a new framework for four-dimensional (4D) event imaging using a single static neuromorphic camera.We take advantage of the inherent sparsity of event data to combine optically encoded stereo channels into a single event camera.By utilizing optical channel multiplexing,we maintain sensor resolution while retaining the key advantages of event cameras.展开更多
Electrons in the energy range of 10–100 keV are important energetic particle components in the magnetosphere,and they play a key role in many physical processes in the magnetosphere.However,many scientific questions ...Electrons in the energy range of 10–100 keV are important energetic particle components in the magnetosphere,and they play a key role in many physical processes in the magnetosphere.However,many scientific questions about these processes are still unanswered.High spatiotemporal and energy-resolution imaging detection of 10–100 keV electrons is of great significance for solving these scientific problems.The traditional space particle detection technology cannot effectively detect the medium-energy electrons in this energy range.In this project,we propose combining low-noise particle detection technology with pinhole imaging technology to achieve high-resolution imaging detection of 10–100 keV medium-energy electrons in the magnetosphere,and at the same time achieve miniaturization(≤3.2 kg and size of 150×150×170 mm)and low power consumption(≤5 W)of the instrument,which can be used for space physics research and space weather applications in the future.展开更多
Live imaging enables direct observation of dynamic biological processes,capturing their progression from molecular to organismal scales in space and time.Through high-resolution observation,it provides a powerful mean...Live imaging enables direct observation of dynamic biological processes,capturing their progression from molecular to organismal scales in space and time.Through high-resolution observation,it provides a powerful means to decode biological complexity by revealing dynamic behaviors,spatial patterns,and regulatory changes.This review illustrates the application of live imaging in investigating complex biological processes with spatiotemporal resolution and mechanistic insight.We first highlight the analytical power and integrative strategies of live imaging,and then summarize recent advances that further extend its capacities.We then focus on four complex processes―cell proliferation,lineage regulation,morphogenesis,and atlas construction―to elucidate how live imaging contributes to their decoding through representative studies.We also discuss the conceptual and practical limitations that currently constrain the full interpretive potential of live imaging,underscoring the need for deeper integration between observation,perturbation,and modeling.Looking ahead,live imaging will benefit from both technical refinement and advances in data standardization and visualization,functional quantification,multiscale integration,and the discovery of generalizable principles.Together,these directions advance a more integrative and mechanistic understanding of complex biological processes.展开更多
The photoacoustic imaging of lipid is intrinsically constrained by the feeble nature of endogenous lipid signals,posing a persistent sensitivity challenge that demands innovative solutions.Although adopting high-effic...The photoacoustic imaging of lipid is intrinsically constrained by the feeble nature of endogenous lipid signals,posing a persistent sensitivity challenge that demands innovative solutions.Although adopting high-efficiency excitation and detection elements may improve the imaging sensitivity to a certain extent,the application of the elements is inevitably subject to various limitations in practical applications,particularly during in vivo imaging and endoscopic imaging.In this study,we propose a multi-combinatorial approach to enhance the sensitivity of lipid photoacoustic imaging.The approach involves wavelet transform processing of one-dimensional A-line signals,gradient-based denoising of two-dimensional B-scan images,and finally,threedimensional spatial weighted averaging of the data processed by the previous two steps.This method not only significantly improves the signal-to-noise ratio(SNR)in distinguished feature regions of the image by around 10 dB,but also efficiently extracts weak signals with no distinct features in the original image.After processing with this method,the images acquired under single scanning were compared with those obtained under multiple scanning.The results showed highly consistent image features,with the structural similarity index increasing from 0.2 to 0.8,confirming the accuracy and reliability of the multi-combinatorial approach.展开更多
Carbon dots(CDs),a class of emerging fluorescent nanomaterials,have garnered notable attention in the biomedical field owing to their outstanding photoluminescence properties,excellent biocompatibility,and ease of syn...Carbon dots(CDs),a class of emerging fluorescent nanomaterials,have garnered notable attention in the biomedical field owing to their outstanding photoluminescence properties,excellent biocompatibility,and ease of synthesis and functionalization.Recently,numerous CDs have been developed that allow precise subcellular localization through surface modifications or covalent conjugation with targeting ligands such as peptides,small molecules,Golgi-specific agents,and cell membrane-specific agents.This review begins with an overview of the synthesis strategies of CDs,highlighting their exceptional optical properties,stability,biocompatibility,and significance for subcellular imaging.The mechanisms by which CDs target specific organelles,including the nucleus,mitochondrion,lysosomes,Golgi apparatus,and cell membrane,are discussed.These mechanisms include specific targeting molecules,pH-sensitive targeting,charge-driven interactions,and hydrophobic and hydrophilic dynamics.Furthermore,we summarize their applications in subcellular imaging,such as the long-term dynamic monitoring of organelles,sensing,reactive oxygen species scavenging,and therapy.By presenting a comprehensive review of CDs in subcellular imaging,we aim to pave the way for further development of CDs in bioimaging and related biomedical applications.展开更多
Generative Adversarial Networks(GANs)have become valuable tools in medical imaging,enabling realistic image synthesis for enhancement,augmentation,and restoration.However,their integration into clinical workflows rais...Generative Adversarial Networks(GANs)have become valuable tools in medical imaging,enabling realistic image synthesis for enhancement,augmentation,and restoration.However,their integration into clinical workflows raises concerns,particularly the risk of subtle distortions or hallucinations that may undermine diagnostic accuracy and weaken trust in AI-assisted decision-making.To address this challenge,we propose a hybrid deep learning framework designed to detect GAN-induced artifacts in medical images,thereby reinforcing the reliability of AI-driven diagnostics.The framework integrates low-level statistical descriptors,including high-frequency residuals and Gray-Level Co-occurrence Matrix(GLCM)texture features,with high-level semantic representations extracted from a pre-trained ResNet18.This dual-stream approach enables detection of both pixel-level anomalies and structural inconsistencies introduced by GAN-based manipulation.We validated the framework on a curated dataset of 10,000 medical images,evenly split between authentic and GAN-generated samples across four modalities:MRI,CT,X-ray,and fundus photography.To improve generalizability to real-world clinical settings,we incorporated domain adaptation strategies such as adversarial training and style transfer,reducing domain shift by 15%.Experimental results demonstrate robust performance,achieving 92.6%accuracy and an F1-score of 0.91 on synthetic test data,and maintaining strong performance on real-world GAN-modified images with 87.3%accuracy and an F1-score of 0.85.Additionally,the model attained an AUC of 0.96 and an average precision of 0.92,outperforming conventional GAN detection pipelines and baseline Convolutional Neural Network(CNN)architectures.These findings establish the proposed framework as an effective and reliable solution for detecting GAN-induced hallucinations in medical imaging,representing an important step toward building trustworthy and clinically deployable AI systems.展开更多
The spinal cord links the brain and the peripheral nervous system and has important sensory and motor functions.Impairments in the spinal cord occur in different diseases,such as spinal cord injury,multiple sclerosis,...The spinal cord links the brain and the peripheral nervous system and has important sensory and motor functions.Impairments in the spinal cord occur in different diseases,such as spinal cord injury,multiple sclerosis,pain,motor neuron diseases,and neurodegenerative diseases.Imaging of the spinal cord has been challenging,partly due to its small size and deep anatomical location.Additionally,in an animal model,motion artifacts further influence the in vivo imaging quality of the spinal cord.Recent advances have pushed boundaries for in vivo imaging in living animals(even behaving animals).展开更多
Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience...Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience-dependent mechanisms.The pruning process involves multiple molecular signals and a series of regulatory activities governing the“eat me”and“don't eat me”states.Under physiological conditions,the interaction between glial cells and neurons results in the clearance of unnecessary synapses,maintaining normal neural circuit functionality via synaptic pruning.Alterations in genetic and environmental factors can lead to imbalanced synaptic pruning,thus promoting the occurrence and development of autism spectrum disorder,schizophrenia,Alzheimer's disease,and other neurological disorders.In this review,we investigated the molecular mechanisms responsible for synaptic pruning during neural development.We focus on how synaptic pruning can regulate neural circuits and its association with neurological disorders.Furthermore,we discuss the application of emerging optical and imaging technologies to observe synaptic structure and function,as well as their potential for clinical translation.Our aim was to enhance our understanding of synaptic pruning during neural development,including the molecular basis underlying the regulation of synaptic function and the dynamic changes in synaptic density,and to investigate the potential role of these mechanisms in the pathophysiology of neurological diseases,thus providing a theoretical foundation for the treatment of neurological disorders.展开更多
The unique advantage of x-ray ghost imaging(XGI)is its potential in low dose radiology.One of the practical ways to reduce the radiation exposure is to reduce the measurements while remaining sufficient image quality....The unique advantage of x-ray ghost imaging(XGI)is its potential in low dose radiology.One of the practical ways to reduce the radiation exposure is to reduce the measurements while remaining sufficient image quality.Synthetic aperture x-ray ghost imaging(SAXGI)is invented to achieve megapixel XGI with limited measurements,which is expected to implement XGI simultaneously with large field of view and low radiation exposure.In this paper,we experimentally investigate the effect of measurements reduction on the spatial resolution and image quality of SAXGI with standard sample and biomedical specimen.The results with a resolution chart demonstrated that at 360 measurements,SAXGI successfully retrieved the sample image of 1960×1960 pixels with spatial resolution of 4μm.With measurement reduction,the spatial resolution deteriorates but the sparser structures are still discernable.Even with measurements reduced to 10,a spatial resolution of 10μm can still be achieved by SAXGI.A biomedical sample of a fish specimen is employed to evaluate the method and the fish image of 2000×1000 pixels with an SSIM of 0.962 is reconstructed by SAXGI with 770measurements,corresponding to an accumulative exposure reduction of more than 2 times.With the measurements reduced to 10 which corresponds to 1/160 of the accumulative radiation exposure for conventional radiology,bulky structure like the fish skeleton can still be definitely discerned and the SSIM for the reconstructed image still retained 0.9179.Results of this paper demonstrate that measurements reduction is practicable for the radiation exposure reduction of the sample,which implicates that SAXGI with limited measurements is an efficient solution for low dose radiology.展开更多
In vivo imaging of neurodegenerative diseases provides valuable insights into disease mechanisms and potential therapeutic interventions.Many ocular diseases are closely linked to neurodegenerative conditions affectin...In vivo imaging of neurodegenerative diseases provides valuable insights into disease mechanisms and potential therapeutic interventions.Many ocular diseases are closely linked to neurodegenerative conditions affecting the brain,making the eye a unique and accessible model for studying these disorders.The transparency of eyes allows researchers to monitor disease progression non-invasively,offering a window into neural health.展开更多
Microwave ablation(MWA)is a minimally invasive technique for treating hepatic tumors,necessitating precise monitoring to ensure treatment efficacy and minimize damage to surrounding tissues.This study explores the pot...Microwave ablation(MWA)is a minimally invasive technique for treating hepatic tumors,necessitating precise monitoring to ensure treatment efficacy and minimize damage to surrounding tissues.This study explores the potential of photoacoustic imaging(PAI)in monitoring MWA by examining ex vivo porcine liver tissues.In this study,a comprehensive analysis of photoacoustic signals was performed to compare the main lobe width(MLW)between ablated and normal regions in porcine liver tissue.Histological staining with succinate dehydrogenase(SDH)and shear wave elastography(SWE)were employed to validate the changes in tissue elasticity after ablation.The analysis demonstrated a notable reduction in the MLW of the average A-lines in ablated tissues compared to nonablated regions(p<0.01).This reduction,attributed to increased tissue density and enhanced elasticity,indicates accelerated sound propagation in thermally ablated areas,which then serves as a critical parameter for mapping tissue characteristics.The reconstruction of the MLW distribution successfully delineated the ablated regions,and was consistent with the results of SDH staining and SWE.In addition,MLW-based imaging exhibited higher spatial resolution compared to SWE.Incorporating MLW analysis into PAI may be a promising strategy to improve the accuracy and effectiveness of MWA monitoring in clinical settings.展开更多
基金Supported by the National Natural Science Foundation of China(82371373,W2412120)the Shanghai Natural Science Foundation(21ZR1436100).
文摘Ischemia is a significant factor affecting the repair of peripheral nerve injuries,while exosomes have been shown to promote angiogenesis.To further investigate the detailed processes and efficacy of exosome thera⁃py for ischemic peripheral nerve injuries,this study utilized glucose-modified near-infrared-II(NIR-II)quantum dots(QDs)to label adipose-derived stem cell exosomes(QDs-ADSC-Exos),enabling long-term in vivo NIR-II imaging of exosome treatment for ischemic peripheral nerve damage.Experimental results confirmed that QDs can be used for non-invasive in vitro labeling of exosomes,with QDs-ADSC-Exos exhibiting strong fluorescence signals in the NIR-II window and demonstrating favorable NIR-II imaging characteristics in vivo.Notably,QDsADSC-Exos showed accumulation at the site of nerve injury in cases of ischemic peripheral nerve damage.Func⁃tional neurological assessments indicated that QDs-ADSC-Exos effectively promoted neural regeneration.This study highlights the potential of exosomes in treating ischemic peripheral nerve injuries and elucidates the spatio⁃temporal characteristics of exosome therapy,providing objective evidence for the further optimization of exosomebased treatment protocols.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB0530000)the Discipline Construction Foundation of“Double World-class Project”.
文摘Laser wakefield accelerators(LWFAs)offer acceleration gradients up to 1000 times higher than those of conventional radio-frequency accelerators,offering a pathway to significantly more compact and cost-effective accelerator systems.This breakthrough opens up new possibilities for laboratory-scale light sources.All-optical inverse Compton scattering(AOCS)sources driven by LWFAs produce high-brightness,quasimonochromatic X rays with micrometer-scale source sizes,delivering the spatial coherence and resolution required for X-ray phase-contrast imaging(XPCI).These features position AOCS X-ray sources as promising tools for applications in biology,medicine,physics,and materials science.However,previous AOCS-based imaging studies have primarily focused on X-ray absorption imaging.In this work,we report successful experimental demonstrations of edge-enhanced in-line XPCI using energy-tunable,quasi-monochromatic AOCS X rays.With a spatial resolution of~20μm,our results clearly show the potential of high-resolution,AOCS-based XPCI applications.
基金supported by the National Natural Science Foundation of China,No.82071909(to GF)the Natural Science Foundation of Liaoning Province,No.2023-MS-07(to HL)。
文摘Freezing of gait is a significant and debilitating motor symptom often observed in individuals with Parkinson's disease.Resting-state functional magnetic resonance imaging,along with its multi-level feature indices,has provided a fresh perspective and valuable insight into the study of freezing of gait in Parkinson's disease.It has been revealed that Parkinson's disease is accompanied by widespread irregularities in inherent brain network activity.However,the effective integration of the multi-level indices of resting-state functional magnetic resonance imaging into clinical settings for the diagnosis of freezing of gait in Parkinson's disease remains a challenge.Although previous studies have demonstrated that radiomics can extract optimal features as biomarkers to identify or predict diseases,a knowledge gap still exists in the field of freezing of gait in Parkinson's disease.This cross-sectional study aimed to evaluate the ability of radiomics features based on multi-level indices of resting-state functional magnetic resonance imaging,along with clinical features,to distinguish between Parkinson's disease patients with and without freezing of gait.We recruited 28 patients with Parkinson's disease who had freezing of gait(15 men and 13 women,average age 63 years)and 30 patients with Parkinson's disease who had no freezing of gait(16 men and 14 women,average age 64 years).Magnetic resonance imaging scans were obtained using a 3.0T scanner to extract the mean amplitude of low-frequency fluctuations,mean regional homogeneity,and degree centrality.Neurological and clinical characteristics were also evaluated.We used the least absolute shrinkage and selection operator algorithm to extract features and established feedforward neural network models based solely on resting-state functional magnetic resonance imaging indicators.We then performed predictive analysis of three distinct groups based on resting-state functional magnetic resonance imaging indicators indicators combined with clinical features.Subsequently,we conducted 100 additional five-fold cross-validations to determine the most effective model for each classification task and evaluated the performance of the model using the area under the receiver operating characteristic curve.The results showed that when differentiating patients with Parkinson's disease who had freezing of gait from those who did not have freezing of gait,or from healthy controls,the models using only the mean regional homogeneity values achieved the highest area under the receiver operating characteristic curve values of 0.750(with an accuracy of 70.9%)and 0.759(with an accuracy of 65.3%),respectively.When classifying patients with Parkinson's disease who had freezing of gait from those who had no freezing of gait,the model using the mean amplitude of low-frequency fluctuation values combined with two clinical features achieved the highest area under the receiver operating characteristic curve of 0.847(with an accuracy of 74.3%).The most significant features for patients with Parkinson's disease who had freezing of gait were amplitude of low-frequency fluctuation alterations in the left parahippocampal gyrus and two clinical characteristics:Montreal Cognitive Assessment and Hamilton Depression Scale scores.Our findings suggest that radiomics features derived from resting-state functional magnetic resonance imaging indices and clinical information can serve as valuable indices for the identification of freezing of gait in Parkinson's disease.
基金supported by the National Natural Science Foundation of China(61927813,61865009,12104203)Jiangxi Provincial Natu-ral Science Foundation(20212ACB201007)。
文摘Metasurfaces are artificial structures that can finely control the characteristics of electromagnetic waves at subwavelength scales,and they are widely used to manipulate the propagation,phase,amplitude,and polariza⁃tion of light.In this work,a bound state in the continuum(BIC)structure based on a metallic metasurface is pro⁃posed.By adjusting the metallic structure using CST and COMSOL software,a significant quasi-BIC peak can be achieved at a frequency of 0.8217 terahertz(THz).Through multi-level expansion analysis,it is found that the electric dipole(ED)is the main factor contributing to the resonant characteristics of the structure.By leveraging the characteristics of BIC,an imaging system was created and operated.According to the simulation results,the imaging system demonstrated excellent sensitivity and resolution,revealing the great potential of terahertz imag⁃ing.This research not only provides new ideas for the creation of BIC structures but also offers an effective refer⁃ence for the development of high-performance terahertz imaging technology.
文摘Raman imaging,as a molecular spectroscopy technique,has been widely studied and applied in research fields such as life sciences and food safety due to its excellent specificity and high resolution.However,its development still faces challenges such as weak signals,slow acquisition speed,and insufficient penetration depth.In recent years,the rapid development of aggregate science has provided new insights for addressing these limitations.Aggregation-induced emission(AIE)materials exhibit enhanced signals in the aggregated state,which may compensate for the inherent weak Raman signals.This article reviews the cutting-edge progress of Raman imaging technology and its current status in cross-disciplinary research with aggregate science,emphasizing the strategy of constructing AIE-Raman dual-responsive probes through molecular engineering to achieve functional complementarity between fluorescence localization and Raman quantification,thereby significantly improving detection sensitivity and specificity.These probes have demonstrated single-cell resolution and high spatiotemporal accuracy in applications such as tumor surgical navigation,diagnosis and treatment of drug-resistant bacteria,and dynamic monitoring of organelles.We also analyze the bottlenecks in this field,such as biological safety and the complexity of molecular design,and outline the future development directions,including intelligent responsive probes,artificial intelligence-assisted analysis,and multimodal fusion platforms.The integration of Raman imaging and AIE sheds new light in the field of medical imaging.
文摘Two novel aggregation-induced emission(AIE)-active probes,TPA-H and TPA-2 F,were designed and synthesized based on a triphenylamine(TPA)core.Systematic characterization demonstrated that both probes exhibit excellent biocompatibility(cell viability>90%at concentrations up to 50μmol/L)and outstanding LD-targeting speci⁃ficity with minimal colocalization with other organelles such as mitochondria and lysosomes.During early differentia⁃tion of 3 T 3-L 1 adipocytes,both TPA-2 F and TPA-H clearly visualized small and nascent LDs that were difficult to be detected with BODIPY,indicating superior imaging sensitivity compared to the existing fluorescent probes for LDs.Moreover,TPA-2 F demonstrated exceptional photostability,retaining over 90%of its initial fluorescence intensity after 100 continuous laser scanning cycles,significantly outperforming TPA-H.This work not only provides two high-performance LD imaging tools but also highlights the potential of AIE luminogens(AIEgens)in organelle-specific bioimaging,offering promising avenues for early diagnosis and mechanistic research of lipid-related metabolic diseases.
基金funded by the Deanship of Scientific Research(DSR)at King Abdulaziz University,Jeddah,under grant No.(IFPDP-261-22).
文摘Medical imaging is essential in modern health care,allowing accurate diagnosis and effective treatment planning.These images,however,often demonstrate low contrast,noise,and brightness distortion that reduce their diagnostic reliability.This review presents a structured and comprehensive analysis of advanced histogram equalization(HE)-based techniques for medical image enhancement.Our review methodology encompasses:(1)classical HE approaches and related limitations in medical domains;(2)adaptive schemes like Adaptive Histogram Equalization(AHE)and Contrast Limited Adaptive Histogrma Equalization(CLAHE)and their advance variants;(3)brightnesspreserving schemes like BBHE and MMBEBHE and related algorithms;(4)dynamic and recursive histogram equalization methods incorporating DHE and RMSHE;(5)fuzzy logic-based enhancement methodologies addressing uncertainty and noise in medical images;and(6)hybrid optimization methodologies through the application of metaheuristic algorithms(World Cup Optimization,Particle Swarm Optimization,Genetic Algorithms,along with histogram-based methodologies.)There is also a comparative discussion given based on contrast improvement,image brightness preservation,noise management,and computational efficiency.Such advancements have better capabilities of improving image quality,which is more important for improved diagnosis and image analysis.
文摘Background:Sarcomatoid carcinoma of the ureter(SCU)is a highly aggressive and relatively uncommon malignant tumor of the urinary tract.Its frequency is quite low,and its prognosis is very bad when compared to other cancers of the urinary system.SCU clinical reports are still hard to come by.MRI and PEI/CT imaging of ureteral sarcomatoid cancer is presented in this case to promote diagnostic awareness and comprehension of the imaging characteristics of this uncommon illness.Method:The patient had ureteral sarcomatoid cancer,which was verified by pathological investigation after ureteroscopic biopsy.The patient’s clinical information,imaging results,surgical outcomes,and pathological findings were gathered.A retrospective study was carried out in combinationwith pertinent national and international literature.Results:An 84-year-old female patient was admitted for“left flank discomfort lasting over one month.”MRI revealed an irregular soft tissue mass in the middle-lower segment of the left ureter.T2-weighted imaging showed an unevenly slightly hyperintense signal.Diffusion-weighted imaging demonstrated restricted diffusion.Contrastenhanced imaging exhibited heterogeneous enhancement.PET/CT demonstrated significantly increased fluorodeoxyglucose metabolism in the mass with secondary left upper urinary tract obstruction.Concurrent findings included a solitary metastatic lesion in hepatic segment S6 and multiple lymph node metastases along the left common iliac and external iliac arteries.Preoperative diagnosis suggested a malignant tumor of the ureter.The patient underwent left nephroureteroscopy with biopsy,and the postoperative pathological diagnosis was ureteral sarcomatoid carcinoma.Conclusion:Ureteral sarcomatoid carcinoma is a rare,highly malignant,and aggressive tumor with nonspecific imaging features,typically presenting as an invasively growing mass.Diagnosis relies on postoperative pathology and immunohistochemical examination.MRI and PET/CT scans are valuable for preoperative localization and characterization,tumor staging,treatment planning,and postoperative follow-up.The prognosis is extremely negative.The main treatment option is radical surgery,although constant monitoring is necessary since early recurrence and metastases are frequent after surgery.
基金supported by the National Natural Science Foundation of China(Nos.82372116,U23A2097)Guangdong Basic and Applied Basic Research Foundation(No.2022A1515010620)+2 种基金Shenzhen Medical Research Fund(Nos.B2302047,A2302047)Shenzhen Science and Technology Program(No.JCYJ20220818095806014)Research Team Cultivation Program of Shenzhen University(No.2023QNT019).
文摘The level of glutathione(GSH)is significantly associated with numerous pathological processes,thus,real-time detection of the GSH level is of significance for early diagnosis of GSH-related diseases.Herein,we developed in vivo second near-infrared(NIR-II)window fluorescence(FL)and ratiometric photoacoustic(RPA)dual-modality imaging of GSH using a GSH-activatable probe(LET-14).LET-14 was synthesized based on a rhodamine hybrid xanthene skeleton with a FL shielding 2,4-dinitrobenzene sulfonyl group that can be specifically cleaved by GSH,thus resulting in a markedly bathochromic-shift absorption,a 6.5-fold increase in NIR-II FL intensity(FL_(920))and a 13-fold increase in RPA signal(PA_(880)/PA_(705))in vitro.Intriguingly,LET-14 exhibits good selectivity and sensitivity for NIR-II FL and RPA dual-modality imaging of GSH in 4T1 tumor-bearing mouse model.Our findings develop an in vivo detection tool of GSH,which has great potential in the field of cancer diagnosis.
基金support from the Kreitman School of Advanced Graduate Studies, Ben-Gurion University of the Negev。
文摘Neuromorphic cameras,or dynamic vision sensors,are bio-inspired event cameras that measure changes in the image brightness asynchronously and independently at the pixel level.Recently,they garnered increasing interest due to their extremely high temporal resolution,wide dynamic range,low power consumption,and high pixel bandwidth.Despite their advantages,most existing three-dimensional (3D) event imaging solutions rely on multicamera configurations,which are costly,complex,and challenging to synchronize.In this study,we introduce a new framework for four-dimensional (4D) event imaging using a single static neuromorphic camera.We take advantage of the inherent sparsity of event data to combine optically encoded stereo channels into a single event camera.By utilizing optical channel multiplexing,we maintain sensor resolution while retaining the key advantages of event cameras.
基金supported by the National Natural Science Foundation of China(Grant No.42274225)the International Science and Technology Cooperation Project of the Ningbo Key R&D Program(Grant No.2024H031).
文摘Electrons in the energy range of 10–100 keV are important energetic particle components in the magnetosphere,and they play a key role in many physical processes in the magnetosphere.However,many scientific questions about these processes are still unanswered.High spatiotemporal and energy-resolution imaging detection of 10–100 keV electrons is of great significance for solving these scientific problems.The traditional space particle detection technology cannot effectively detect the medium-energy electrons in this energy range.In this project,we propose combining low-noise particle detection technology with pinhole imaging technology to achieve high-resolution imaging detection of 10–100 keV medium-energy electrons in the magnetosphere,and at the same time achieve miniaturization(≤3.2 kg and size of 150×150×170 mm)and low power consumption(≤5 W)of the instrument,which can be used for space physics research and space weather applications in the future.
基金supported by the National Key Research and Development Program of China(2022YFA1303000 and 2021YFA0805800)the National Natural Science Foundation of China(32325032)the Chinese Academy of Sciences Project for Young Scientists in Basic Research(YSBR-073).
文摘Live imaging enables direct observation of dynamic biological processes,capturing their progression from molecular to organismal scales in space and time.Through high-resolution observation,it provides a powerful means to decode biological complexity by revealing dynamic behaviors,spatial patterns,and regulatory changes.This review illustrates the application of live imaging in investigating complex biological processes with spatiotemporal resolution and mechanistic insight.We first highlight the analytical power and integrative strategies of live imaging,and then summarize recent advances that further extend its capacities.We then focus on four complex processes―cell proliferation,lineage regulation,morphogenesis,and atlas construction―to elucidate how live imaging contributes to their decoding through representative studies.We also discuss the conceptual and practical limitations that currently constrain the full interpretive potential of live imaging,underscoring the need for deeper integration between observation,perturbation,and modeling.Looking ahead,live imaging will benefit from both technical refinement and advances in data standardization and visualization,functional quantification,multiscale integration,and the discovery of generalizable principles.Together,these directions advance a more integrative and mechanistic understanding of complex biological processes.
基金supported by the National Key Research and Development Program of China(2022YFC2402400)the National Natural Science Foundation of China(82027803,62275062)+7 种基金the Guangdong Provincial Key Laboratory of Biomedical Optical Imaging Technology(2020B121201010)the Shenzhen Science and Technology Innovation Committee under Grant(JCYJ20220818101417039)the Shenzhen Key Laboratory for Molecular lmaging(ZDSY20130401165820357)the Shenzhen Medical Research Fund(D2404002)the Project of Shandong Innovation and Startup Community of High-end Medical Apparatus and Instruments(2023-SGTTXM-002 and 2024-SGTTXM-005)the Shandong Province Technology Innovation Guidance Plan(Central Leading Local Science and Technology Development Fund)(YDZX2023115)the Taishan Scholar Special Funding Project of Shandong Provinceand the Shandong Laboratory of Advanced Biomaterials and Medical Devices in Weihai(ZL202402).
文摘The photoacoustic imaging of lipid is intrinsically constrained by the feeble nature of endogenous lipid signals,posing a persistent sensitivity challenge that demands innovative solutions.Although adopting high-efficiency excitation and detection elements may improve the imaging sensitivity to a certain extent,the application of the elements is inevitably subject to various limitations in practical applications,particularly during in vivo imaging and endoscopic imaging.In this study,we propose a multi-combinatorial approach to enhance the sensitivity of lipid photoacoustic imaging.The approach involves wavelet transform processing of one-dimensional A-line signals,gradient-based denoising of two-dimensional B-scan images,and finally,threedimensional spatial weighted averaging of the data processed by the previous two steps.This method not only significantly improves the signal-to-noise ratio(SNR)in distinguished feature regions of the image by around 10 dB,but also efficiently extracts weak signals with no distinct features in the original image.After processing with this method,the images acquired under single scanning were compared with those obtained under multiple scanning.The results showed highly consistent image features,with the structural similarity index increasing from 0.2 to 0.8,confirming the accuracy and reliability of the multi-combinatorial approach.
基金support received from the National Natural Science Foundation of China(No.U24A2079).
文摘Carbon dots(CDs),a class of emerging fluorescent nanomaterials,have garnered notable attention in the biomedical field owing to their outstanding photoluminescence properties,excellent biocompatibility,and ease of synthesis and functionalization.Recently,numerous CDs have been developed that allow precise subcellular localization through surface modifications or covalent conjugation with targeting ligands such as peptides,small molecules,Golgi-specific agents,and cell membrane-specific agents.This review begins with an overview of the synthesis strategies of CDs,highlighting their exceptional optical properties,stability,biocompatibility,and significance for subcellular imaging.The mechanisms by which CDs target specific organelles,including the nucleus,mitochondrion,lysosomes,Golgi apparatus,and cell membrane,are discussed.These mechanisms include specific targeting molecules,pH-sensitive targeting,charge-driven interactions,and hydrophobic and hydrophilic dynamics.Furthermore,we summarize their applications in subcellular imaging,such as the long-term dynamic monitoring of organelles,sensing,reactive oxygen species scavenging,and therapy.By presenting a comprehensive review of CDs in subcellular imaging,we aim to pave the way for further development of CDs in bioimaging and related biomedical applications.
基金supported and funded by the Deanship of Scientific Research at Imam Mohammad Ibn Saud Islamic University(IMSIU)(grant number IMSIU-DDRSP2601).
文摘Generative Adversarial Networks(GANs)have become valuable tools in medical imaging,enabling realistic image synthesis for enhancement,augmentation,and restoration.However,their integration into clinical workflows raises concerns,particularly the risk of subtle distortions or hallucinations that may undermine diagnostic accuracy and weaken trust in AI-assisted decision-making.To address this challenge,we propose a hybrid deep learning framework designed to detect GAN-induced artifacts in medical images,thereby reinforcing the reliability of AI-driven diagnostics.The framework integrates low-level statistical descriptors,including high-frequency residuals and Gray-Level Co-occurrence Matrix(GLCM)texture features,with high-level semantic representations extracted from a pre-trained ResNet18.This dual-stream approach enables detection of both pixel-level anomalies and structural inconsistencies introduced by GAN-based manipulation.We validated the framework on a curated dataset of 10,000 medical images,evenly split between authentic and GAN-generated samples across four modalities:MRI,CT,X-ray,and fundus photography.To improve generalizability to real-world clinical settings,we incorporated domain adaptation strategies such as adversarial training and style transfer,reducing domain shift by 15%.Experimental results demonstrate robust performance,achieving 92.6%accuracy and an F1-score of 0.91 on synthetic test data,and maintaining strong performance on real-world GAN-modified images with 87.3%accuracy and an F1-score of 0.85.Additionally,the model attained an AUC of 0.96 and an average precision of 0.92,outperforming conventional GAN detection pipelines and baseline Convolutional Neural Network(CNN)architectures.These findings establish the proposed framework as an effective and reliable solution for detecting GAN-induced hallucinations in medical imaging,representing an important step toward building trustworthy and clinically deployable AI systems.
文摘The spinal cord links the brain and the peripheral nervous system and has important sensory and motor functions.Impairments in the spinal cord occur in different diseases,such as spinal cord injury,multiple sclerosis,pain,motor neuron diseases,and neurodegenerative diseases.Imaging of the spinal cord has been challenging,partly due to its small size and deep anatomical location.Additionally,in an animal model,motion artifacts further influence the in vivo imaging quality of the spinal cord.Recent advances have pushed boundaries for in vivo imaging in living animals(even behaving animals).
基金supported by the National Natural Science Foundation of China,No.31760290,82160688the Key Development Areas Project of Ganzhou Science and Technology,No.2022B-SF9554(all to XL)。
文摘Synaptic pruning is a crucial process in synaptic refinement,eliminating unstable synaptic connections in neural circuits.This process is triggered and regulated primarily by spontaneous neural activity and experience-dependent mechanisms.The pruning process involves multiple molecular signals and a series of regulatory activities governing the“eat me”and“don't eat me”states.Under physiological conditions,the interaction between glial cells and neurons results in the clearance of unnecessary synapses,maintaining normal neural circuit functionality via synaptic pruning.Alterations in genetic and environmental factors can lead to imbalanced synaptic pruning,thus promoting the occurrence and development of autism spectrum disorder,schizophrenia,Alzheimer's disease,and other neurological disorders.In this review,we investigated the molecular mechanisms responsible for synaptic pruning during neural development.We focus on how synaptic pruning can regulate neural circuits and its association with neurological disorders.Furthermore,we discuss the application of emerging optical and imaging technologies to observe synaptic structure and function,as well as their potential for clinical translation.Our aim was to enhance our understanding of synaptic pruning during neural development,including the molecular basis underlying the regulation of synaptic function and the dynamic changes in synaptic density,and to investigate the potential role of these mechanisms in the pathophysiology of neurological diseases,thus providing a theoretical foundation for the treatment of neurological disorders.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2022YFA1603601,2021YFF0601203,and 2021YFA1600703)。
文摘The unique advantage of x-ray ghost imaging(XGI)is its potential in low dose radiology.One of the practical ways to reduce the radiation exposure is to reduce the measurements while remaining sufficient image quality.Synthetic aperture x-ray ghost imaging(SAXGI)is invented to achieve megapixel XGI with limited measurements,which is expected to implement XGI simultaneously with large field of view and low radiation exposure.In this paper,we experimentally investigate the effect of measurements reduction on the spatial resolution and image quality of SAXGI with standard sample and biomedical specimen.The results with a resolution chart demonstrated that at 360 measurements,SAXGI successfully retrieved the sample image of 1960×1960 pixels with spatial resolution of 4μm.With measurement reduction,the spatial resolution deteriorates but the sparser structures are still discernable.Even with measurements reduced to 10,a spatial resolution of 10μm can still be achieved by SAXGI.A biomedical sample of a fish specimen is employed to evaluate the method and the fish image of 2000×1000 pixels with an SSIM of 0.962 is reconstructed by SAXGI with 770measurements,corresponding to an accumulative exposure reduction of more than 2 times.With the measurements reduced to 10 which corresponds to 1/160 of the accumulative radiation exposure for conventional radiology,bulky structure like the fish skeleton can still be definitely discerned and the SSIM for the reconstructed image still retained 0.9179.Results of this paper demonstrate that measurements reduction is practicable for the radiation exposure reduction of the sample,which implicates that SAXGI with limited measurements is an efficient solution for low dose radiology.
基金supported[in part]by the IntramuralResearch Program of the National Institutes ofHealth(NIH)(to KJM),and also supported by theOffice by the Office of the Assistant Secretary ofDefense for Health Affairs and the Defense HealthAgency J9,Research and Development Directorate,through the Vision Research Program under AwardNo.(CDMRPL-18-0-VR180205 to KJM and FMN-N).
文摘In vivo imaging of neurodegenerative diseases provides valuable insights into disease mechanisms and potential therapeutic interventions.Many ocular diseases are closely linked to neurodegenerative conditions affecting the brain,making the eye a unique and accessible model for studying these disorders.The transparency of eyes allows researchers to monitor disease progression non-invasively,offering a window into neural health.
基金supported by the National Natural Science Foundation of China(82427808,61875085)the Jiangsu Provincial University Natural Science Foundation(25KJB413004)+1 种基金the Nanjing Health Science and Technology Development Foundation(ZKX24043)the Fundamental Research Funds for the Central Universities(NJ2024029).
文摘Microwave ablation(MWA)is a minimally invasive technique for treating hepatic tumors,necessitating precise monitoring to ensure treatment efficacy and minimize damage to surrounding tissues.This study explores the potential of photoacoustic imaging(PAI)in monitoring MWA by examining ex vivo porcine liver tissues.In this study,a comprehensive analysis of photoacoustic signals was performed to compare the main lobe width(MLW)between ablated and normal regions in porcine liver tissue.Histological staining with succinate dehydrogenase(SDH)and shear wave elastography(SWE)were employed to validate the changes in tissue elasticity after ablation.The analysis demonstrated a notable reduction in the MLW of the average A-lines in ablated tissues compared to nonablated regions(p<0.01).This reduction,attributed to increased tissue density and enhanced elasticity,indicates accelerated sound propagation in thermally ablated areas,which then serves as a critical parameter for mapping tissue characteristics.The reconstruction of the MLW distribution successfully delineated the ablated regions,and was consistent with the results of SDH staining and SWE.In addition,MLW-based imaging exhibited higher spatial resolution compared to SWE.Incorporating MLW analysis into PAI may be a promising strategy to improve the accuracy and effectiveness of MWA monitoring in clinical settings.
