Imaging Tool Research Articles

Two-Photon Cellular and Intravital Imaging of Hypochlorous Acid by Fluorescent Probes That Exhibit a Synergistic Excited-State Intramolecular Proton Transfer-Intramolecular Charge Transfer Mechanism Enabling Near-Infrared Emission with a Large Stokes Shift.

To develop highly effective molecular tools for intravital imaging of hypochlorous acid (HOCl), in this study, we initially designed two-photon hybrid fluorophores, SDP and P-SDP, by conjugating the classical dye 2-(2'-hydroxyphenyl)benzothiazole with the two-photon hydroxylphenyl-butadienylpyridinium fluorophore. The designed fluorophores exhibit a synergistic interaction between excited-state intramolecular proton transfer and intramolecular charge transfer mechanisms, enabling near-infrared (NIR) emission and significant Stokes shifts. Subsequently, using these fluorophores, we developed two HOCl fluorescent probes, SDP-SN and P-SDP-SN, by further incorporating N,N-dimethylthiocarbamate as a specific recognition group for HOCl. Toward HOCl, both SDP-SN and P-SDP-SN demonstrate an ultrafast response (less than 3 s), NIR emission at wavelengths of 714 and 682 nm, and remarkable Stokes shifts of 303 and 271 nm, respectively. Leveraging these advantages in conjunction with their ability to cross the blood-brain barrier, the probes find successful application in two-photon cellular and intravital imaging of HOCl. This includes visualizing endogenous generation of HOCl in cellular models related to inflammation, hyperglycemia, and ferroptosis, as well as mapping in vivo generation of HOCl within the brain and abdominal cavity using a murine model of systemic inflammation.

Novel imaging tools to study mitochondrial morphology in Caenorhabditis elegans.

Mitochondria exhibit a close interplay between their structure and function. Understanding this intricate relationship requires advanced imaging techniques that can capture the dynamic nature of mitochondria and their impact on cellular processes. However, much of the work on mitochondrial dynamics has been performed in single celled organisms or in vitro cell culture. Here, we introduce novel genetic tools for live imaging of mitochondrial morphology in the nematode Caenorhabditis elegans, addressing a pressing need for advanced techniques in studying organelle dynamics within live intact multicellular organisms. Through a comprehensive analysis, we directly compare our tools with existing methods, demonstrating their advantages for visualizing mitochondrial morphology and contrasting their impact on organismal physiology. We reveal limitations of conventional techniques, whereas showcasing the utility and versatility of our approaches, including endogenous CRISPR tags and ectopic labeling. By providing a guide for selecting the most suitable tools based on experimental goals, our work advances mitochondrial research in C. elegans and enhances the strategic integration of diverse imaging modalities for a holistic understanding of organelle dynamics in living organisms.

A large field-of-view, single-cell-resolution two- and three-photon microscope for deep and wide imaging

In vivo imaging of large-scale neuronal activity plays a pivotal role in unraveling the function of the brain's circuitry. Multiphoton microscopy, a powerful tool for deep-tissue imaging, has received sustained interest in advancing its speed, field of view and imaging depth. However, to avoid thermal damage in scattering biological tissue, field of view decreases exponentially as imaging depth increases. We present a suite of innovations to optimize three-photon microscopy for large field-of-view imaging at depths unreachable by two-photon microscopy. These techniques enable us to image neuronal activities of transgenic animals expressing protein calcium sensors in a ~ 3.5-mm diameter field-of-view with single-cell resolution in the deepest cortical layer of mouse brains. We further demonstrate simultaneous large field-of-view two-photon and three-photon imaging, subcortical imaging in the mouse brain, and whole-brain imaging in adult zebrafish. The demonstrated techniques can be integrated into typical multiphoton microscopes to enlarge field of view for system-level neural circuit research.

Mitochondria-Targetable Cyclometalated Iridium(III) Complex-Based Luminescence Probe for Monitoring and Assessing Treatment Response of Ferroptosis-Mediated Hepatic Ischemia-Reperfusion Injury.

Ferroptosis plays an essential role in the pathological progression of hepatic ischemia-reperfusion injury (HIRI), which is closely related to iron-dependent lipid peroxidation. Since mitochondria are thought to be the major site of reactive oxygen species (ROS) production and iron storage, monitoring the variations of mitochondrial hypochlorous acid (HClO) (an important member of ROS) has important implications for the assessment of ferroptosis status, as well as the formulation of treatment strategies for HIRI. However, reliable imaging tools for the visualization of mitochondrial HClO and monitoring its dynamic changes in ferroptosis-mediated HIRI are still lacking. Herein, in this work, an HClO-activated near-infrared (NIR) cyclometalated iridium(III) complex-based probe, named NIR-Ir-HClO, was developed for the visual monitoring of the mitochondrial HClO fluxes in ferroptosis-mediated HIRI. The newly prepared probe showed fast response (<30 s), good sensitivity, excellent selectivity, good cell biocompatibility, and satisfactory mitochondrial-targeting performance, making it suitable for accurate monitoring of mitochondrial HClO in living cells. Moreover, visualization of the variations of mitochondrial HClO in ferroptosis-mediated HIRI and monitoring of the treatment response of ferroptosis-mediated HIRI to the ferroptosis inhibitors were achieved for the first time. All these show that probe NIR-Ir-HClO can be utilized as a reliable imaging tool for revealing the pathological mechanism of mitochondrial HClO in ferroptosis-mediated HIRI, as well as for the formulation of new treatment strategies for HIRI.

Recent Updates of PET in Lymphoma: FDG and Beyond

Lymphoma is one of the most common cancers worldwide, categorized into Hodgkin lymphoma and non-Hodgkin lymphoma. 18F-fluorodeoxyglucose positron emission tomography (FDG PET) has become an essential imaging tool for evaluating patients with lymphoma in terms of initial diagnosis, staging, prognosis, and treatment response assessment. Recent advancements in imaging technology and methodologies, along with the development of artificial intelligence, have revolutionized the evaluation of complex imaging data, enhancing the diagnostic and predictive power of PET in lymphoma. However, FDG is not cancer-specific, but it primarily reflects glucose metabolism, which has prompted the investigation of alternative PET tracers to address this limitation. Novel PET radiotracers, such as fibroblast activation protein inhibitors targeting the tumor microenvironment, have recently shown promising results in evaluating various malignancies compared to FDG PET. Furthermore, with the rapid advancements in immunotherapy and the favorable imaging properties of 89Zr, immunoPET has emerged as a promising modality, offering insights into the functional and molecular status of the immune system. ImmunoPET can also facilitate the development of new antibody therapeutics and radioimmunotherapy by providing pharmacokinetic and pharmacodynamic data. This review provides comprehensive insights into the current clinical applications of FDG PET in lymphoma, while also exploring novel PET imaging radiotracers beyond FDG, discussing their mechanisms of action and potential impact on patient management.

In-depth morphological and functional analysis of ATTR-CA myocardial cells and niche by electron microscopic 3D reconstruction

Abstract Background Cell-cell interactions and interplay with extracellular matrix are known to be important in the steady state and pathological conditions, including wild-type transthyretin cardiac amyloidosis (wtATTR-CA). However, alterations of the microstructure of cardiomyocytes (CMs) and cardiac niches have not been well analyzed. Normal histological staining is usually limited in resolution, and 2D electron microscopy cannot capture stereoscopic images or the distribution of target particles and organelles in intra- and extracellular 3D space, so novel methods are being attempted. Methods and Results Using Serial Block Face-Scanning Electron Microscopy (SBF-SEM) and a 3D structural reconstruction system, we for the first time investigated the microstructure of human myocardial tissue from control hypertrophied heart (hypertensive heart disease) and wtATTR-CA patients. The microstructure of myocardial niche, cell morphology/numbers, and the distribution of intracellular organelles such as intercalated discs (ICDs) were compared to control endomyocardial biopsy (EMB) samples (2 controls vs 5 wtATTR-CA patients). In all wtATTR-CA samples, amyloid fibers were deposited originating around the capillary structures with various electron densities, compressing myocardial cells not only from the periphery but also dividing them from the center of the cell body, and CMs showed degeneration and dwarfing according to the severity of amyloid fiber deposition (Figure 1). The capillary structures showed degeneration and narrowing with stratified basement membrane, and rarefaction (3378±216.5 vs 1448±116.8/mm2, p&amp;lt;0.0001). Notably, the stromal cells (pericytes, fibroblasts, macrophages) were more likely buried by amyloid fibers than CMs, and their numbers were also reduced, indicating a loss of adjacent and intercellular interaction with capillaries and CMs (Fig. 2, 1892±194.4 vs 1189±107.4 mm2, p=0.0043). This method can also be used to analyze intracellular organelles and microstructures in CMs. In ATTR-CA, morphological abnormalities were observed in ICDs (Figure 3) and mitochondria. Conclusion In the ATTR-CM patients, there was a significant decrease in the number of capillaries in accordance with the deposition of myocardial amyloid fibers, as well as a decrease in stromal cells. These results support the hypothesis that amyloid fibril deposition not only causes chronic myocardial ischemia, but also reduces the number of niche cells, which play a supportive role for CM function and entirely exacerbate the damage. The SBF-SEM is an innovative tool for 3D imaging and quantitative analysis of myocardial ultrastructure and functions.Methods &amp; Figure 1Figure 2 and Figure 3

Exploring Charge Transfer Mechanisms in Schiff Base‐Modified N‐Doped GQDs: Insights from DFT and Pump‐Probe Spectroscopy for Bioimaging Applications

AbstractIn recent developments, graphene quantum dots (GQDs) have emerged as valuable tools for imaging and biosensing. Various modifications on the GQDs with any desired functionality and attachment of organic molecules and/or nanostructures allow tuning their photophysical properties as well as charge transfer dynamics for bioimaging applications. This study focuses on synthesizing and characterizing of polyethyleneimine‐functionalized nitrogen‐doped GQDs (NC1), Schiff base‐ functionalized nitrogen‐doped GQDs (NC2), and silver nanocomposites of these Schiff base‐functionalized nitrogen‐doped GQDs (NC3). We explore their absorption and emission properties to understand their interactions in the ground state. Furthermore, ultrafast transient absorption spectroscopy measurements reveal that the presence of NC3 shortens the excited state lifetime of NC1 due to charge transfer, resulting in reduced fluorescence intensity. Both experimental and DFT results suggest the potential of NC3 for bioimaging and sensing applications, making them promising candidates for phototheranostic purposes.

A novel device for electrocardiographic imaging

Abstract Background Electrocardiographic imaging (ECGi) is a non-invasive imaging tool that allows 3D visualization and characterization of the electrical activity of the heart from measurements on the body surface by solving the so called "inverse problem of electrocardiography". This method helps overcome the limitations of the conventional12-lead ECG in diagnosing and locating heart arrythmias. We developed a textile 34-electrode imageless device (with no need for MRI or CT-scan). Purpose We aim to evaluate the feasibility and safety of the use of a novel textile imageless 34-electrode device for recording ECGi for identification of electrical activity of the heart. Methods and results The performance of a prototype data acquisition system (DAS) was evaluated in 158 individuals. Tests were conducted in three hospitals. The mean age was 43.32 years old (±17.44); mean height 167.31cm (±18.33); mean weight 70kg (±15.68). Almost 88% of the patients were in sinus rhythm. The relative frequencies of the targeted pathologies are listed in Figure 1. The collection of cardiac signals and posterior representation in virtual reality of a stereoscopic, holographic 3D-360º map, was achieved in 100% of the patients. Figure 2 shows the textile hardware with the silver dry electrodes and a screenshot of the software with an example of a voltage map in a patient in sinus rhythm. There were no adverse effects reported. The DAS is composed of 34 electrodes, being their distribution representative of the electrical activity on the torso. Several studies have discussed the minimum number of electrodes on the torso of the patient required to characterize the heart potentials from the electrical potentials on the torso surface through the inverse problem (1,2). We highlight that the representativeness condition of the electrical activity on the torso is crucial to appropriately estimate cardiac activity with the minimum number of leads on the DAS. Conclusion The use of a novel textile imageless 34-electrode device for recording ECGi for identification of electrical activity of the heart is feasible and safe.Targeted rhythmHardware and software

The Value of Cardiac MRI in the Diagnosis of Left Intraventricular Apical Thrombus after Myocardial Infarction: A Case Report

Left ventricular thrombus is a dreadful complication in post-myocardial infarction and should be researched, especially in patients with ventricular dysfunction, given the high thromboembolic risk in these patients. Several studies have shown that transthoracic echocardiography (TTE) lacks specificity when compared with cardiac magnetic resonance imaging (MRI) in the discovery of intraventricular thrombus. However, MRI remains a costly and time-consuming examination, especially in developing countries. In our clinical case, cardiac MRI enabled us to diagnose an apical intra- LV thrombus in the post-infarction period, which guided us in the correct management of the patient and avoided any thromboembolic complications. Today, cardiac MRI confirms its value as a reference imaging tool in the management of ischemic heart disease.

Automated deep learning approach for identifying etiologies of hypertrophic phenocopies by echocardiography

Abstract Background Left ventricular hypertrophy (LVH) is an indicator of poor prognosis across various cardiovascular diseases and is developed by various etiologies. Transthoracic echocardiography (TTE) is the most available cardiac imaging tool to detect LVH. However, it is still challenging to differentiate three non-ischemic cardiomyopathies which frequently presenting LVH: Fabry cardiomyopathy (FC), hypertrophic cardiomyopathy (HCM), and cardiac amyloidosis (CA) from morphology or cardiac function evaluated by TTE. Purpose We aimed to develop stepwise deep learning models to differentiate FC, HCM, and CA using radiomics extracted from TTE. Methods We conducted a retrospective cohort study between 2011 and 2022 in Taiwan. Patients with left ventricular (LV) mass index≥95g/m² in women or ≥115g/m² in men, or the maximal LV wall thickness≥13mm on echocardiography were enrolled. The TTE automatic processing models included four steps: image quality assessment, view classification, auto-segmentation of interventricular septum (IVS), and dynamic radiomics analysis. One echocardiographic study was scanned per patient, and each study contains multiple cardiac cycles. One sample was extracted from each cycle and all samples were evaluated by image quality assessment and view classification model that based on VGG16. Samples with apical four (A4C) and apical five chamber (A5C) views were retained for following steps. Manual contouring of the septal region served as the ground truth for auto-segmentation based on U-Net. The last step was the extraction of dynamic radiomic features from IVS and the dynamic radiomic features were analyzed using an LSTM model to differentiate three hypertrophic cardiomyopathies. Results There were 103 patients with FC, 96 patients with HCM, and 49 patients with CA in this study. Patients with CA were older and had lower LV ejection fraction (EF) than those with FC or HCM (age: 65.8±9.7 vs. 59.3±11.1 vs. 58.6±14.2 years, P=0.002; LVEF: 56.6±10.8 vs. 61.9±8.8 vs. 64.5±8.3%, P&amp;lt;0.001). In addition, patient with FC had larger LV mass index than those with HCM or CA. (Fig. 2A) The details of the performances of four stepwise models were provided in Figure 2 (B-F). The image quality assessment and view classification models achieved accuracies of 91.7% and 95.2%, respectively. The auto-segmentation had the median Dice score as 0.88 for contouring IVS. The results indicated that deep learning algorithms had great ability to recognize different views with proper image quality, and could contour the IVS adequately. The accuracy of dynamic radiomics-based LSTM model to differentiate three hypertrophic phenocopies was 74.5%. Conclusion We developed an automatic process with four stepwise models for analyzing the radiomics of IVS on TTE to differentiate FC, HCM and CA with the modest performance by LSTM model. The developed automatic models may provide potential implications to identify various etiologies LVH in the future.Figure 1-Workflow of this studyFigure 2-Performances of stepwise models

Impact of intravascular imaging on mortality in patients undergoing left main coronary artery PCI. Propensity score matching analysis of the high-volume single centre registry

Abstract Background Recent guidelines endorsed use of intravascular imaging in left main coronary artery (LMCA) percutaneous coronary intervention (PCI). However, impact of adjunctive percutaneous imaging tools on mortality is ambiguous. Purpose The purpose was to investigate impact of intravascular imaging (IVI) on all-cause mortality in patients with LMCA disease. Methods Group of 998 individuals undergoing LMCA PCI was selected from medical records of patients hospitalized in years 2008-2022. Data on mortality were obtained from the Ministry of Digital Affairs. Overall observation time was 14 years (mean 4.3 years). Survival analysis was performed using Cox proportional hazard regression in the overall and propensity-score matched (PSM) population. Results The median age was 71 y.o. (IQR 16), 265 (41.0%) of patients presented with acute myocardial infarction and 183 (20.7%) had history of previous coronary artery bypass grafting (CABG). IVI-guided PCI was performed in 353 (35.4%) patients. In the overall unmatched population, IVI reduced one-year and long-term mortality by 70% (HR 0.3, 95% 0.19-0.47, P&amp;lt;0.001) and 57% (HR 0.43, 95% CI 0.34-0.55, P&amp;lt;0.001). In the subgroup analysis stratified on the history of previous CABG, in patients with unprotected LMCA, IVI resulted in 74% and 63% mortality reduction in the one-year and long-term follow-up (HR 0.26, 95% CI 0.16-0.42, P&amp;lt;0.001; HR 0.37, 95% CI 0.28-0.47, P&amp;lt;0.001; respectively). No influence of IVI on patients with previous CABG was observed. After PSM adjustment for baseline and angiographical characteristics, in the overall population IVI was still associated with significant one-year (HR 0.49, 95% CI 0.25-0.99, P=0.045) and long-term mortality reduction (HR 0.65, 95% CI 0.44-0.97, P=0.03). In patients with unprotected LMCA disease, IVI reduced mortality in two-year observation (HR 0.49, 95% CI 0.26-0.91, P=0.02) and long-term follow-up (HR 0.62, 95% CI 0.41-0.93, P=0.02), with no significant effect in one-year observation. No effect of IVI was observed in the PS-matched cohort of patients with previous CABG. Conclusions Intravascular imaging is associated with significantly better survival in patients undergoing LMCA PCI. The greatest benefit may be obtained in patients with no previous history of CABG. Further studies should investigate subgroups that benefit the most from adjunctive percutaneous tools.PS-matching detailsKaplan-Meier curves in subgroups

Corporate Social Responsibility as A Strategic Tool for Sustainable Organizational Image and Development

Corporate social responsibility has becomes so popular that almost every corporate organization applies it to meet communal and corporate needs. However, the existing studies which centre on the influence of corporate social responsibility on Nigerian breweries’ corporate image remain controversial as they could not have any convergent point. Therefore, this study examined the impact of Nigerian breweries’ corporate social responsibility on its corporate image. The study adopted survey design in form of cross-sectional study through systematic random and purposive sampling. The sample size of 370 members of the host community of Nigerian breweries, Ibadan was derived through Taro Yamane’s proportional sampling formula. The Head of the factory’s Corporate Affairs was also purposively selected for qualitative aspect of the study. Two research instruments were used to collect data: self-designed structured questionnaire (a four-point modified Likert scale method) and a structured interview guide. The instruments were validated and subjected to reliability test using Cronbach’s Alpha analysis; a value of 0.81 was obtained. Data obtained were presented and analyzed using simple frequency counts and percentages, and content analysis. Findings reveal that the Nigerian breweries CSR is effective and meticulously implemented; it’s significantly impacts the corporate image of the company positively. It is recommended that certain aspects of the company’s corporate social responsibility should be reconsidered, including road maintaince, housing support programmes and environmental sanitation. It is concluded that Nigerian breweries should strengthen efforts that will sustain its corporate social responsibility programme.

18F-FDG PET/CT impact in grade 3B follicular lymphoma.

[18F]-fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) is a non-invasive imaging tool that has a fundamental role in the management of FDG-avid lymphoma (also FL) in different settings, especially in the evaluation of treatment response and prognostication. The report by Barraclough etal. demonstrated that the treatment response evaluation by 18F-FDG PET/CT was a strong predictor of prognosis in grade 3B follicular lymphoma (G3BFL). Moreover, among semiquantitative baseline PET features, standardized uptake value (SUV) and TGL showed to be useful in predicting progression-free survival (PFS). Commentary on: Barraclough etal. The value of semiquantitative PET features and end-of-therapy PET in grade 3B follicular lymphoma. Br J Haematol 2024 (Online ahead of print). doi: 10.1111/bjh.19823.

Low-Field Magnetic Resonance Imaging for the Detection of Medial Meniscal Lesions in Cranial Cruciate-Deficient Stifle Joints in Dogs

Background: The aim of this study was to substantiate the ability of noninvasive low-field magnetic resonance imaging (lfMRI) to accurately depict meniscal lesions, thereby establishing lfMRI as a viable option for the diagnosis of meniscal pathology. Study Design: This was a prospective, controlled study. Materials and Methods: In each of 57 stifle joints, 5 predefined lfMRI sequences using a 0.25 T lfMRI were used. The scans were evaluated by an experienced surgeon (DECVS) and through external assessment by a radiologist (DECVDI). The patients were divided into two groups depending on their meniscal status after lfMRI. Dogs (Group 1; n = 33) without lfMRI evidence of medial meniscal pathology underwent TPLO, whereas concurrent craniomedial mini-arthrotomy was performed in patients with suspected meniscal lesions (Group 2; n = 24). Gait assessment was performed 6 weeks later and 6 months postoperatively. Results: Cohen’s kappa value of 0.8571 corresponds to a high level of agreement between the observers. A significant correlation was found between preoperative lameness severity and intraoperative meniscal damage (p &lt; 0.04). The results showed a highly significant correlation between meniscal injuries on MRI and intraoperative findings (p &lt; 0.0001). Conclusions: LfMRI appears to be a noninvasive, reliable imaging tool for the detection of medial meniscal lesions in cranial cruciate-deficient stifle joints, aiming to avoid (minimally) invasive diagnostics in healthy menisci.

Radon-domain acoustic and elastodynamic interferometric redatuming of VSP data

Summary The virtual source method (VSM) is a useful tool for imaging and monitoring below complex and time-varying overburden. When it is applied to VSP geometries, the redatumed virtual source data often suffer from artifacts and aliasing due to the violation of theoretical acquisition conditions and partial focusing of virtual multiples, which further degrade seismic imaging quality. While the conventional Radon-domain VSM (R-VSM) mitigates these issues to some extent, it is still possible to improve upon the imaging. This study develops a simple and effective high-resolution Radon-domain VSM (HR-VSM) to effectively address these issues, offering superior noise and artifact suppression compared to traditional VSM and R-VSM. HR-VSM shows a strong performance across a wide range of VSP configurations and data types, especially in applications to multi-component and passive seismic data, demonstrating its versatility and effectiveness in seismic exploration and showing potential for use in earthquake seismology. To extend subsurface illumination, we combined correlation-type and convolution-type HR-VSM for automatically redatuming virtual surface seismic profile (SSP) shot gathers with a complete receiver array covering all surface source locations, without the additional pre-processing steps typically required by VSM. It was also tested on reverse VSP (RVSP) synthetic active data and passive seismic data, proving effective in constructing virtual shot gathers and showing potential for extending its use to earthquake data and ambient-noise seismology. Moreover, HR-VSM can perform elastodynamic interferometric redatuming, enabling the redatuming of pure P-P and pure P-SV waves from multi-component VSP data. We applied HR-VSM to redatum virtual single well profile (SWP) data containing fault-related P-P and P-SV reflections from VSP data, which were further used for fault imaging. Finally, HR-VSM was used to generate virtual crosswell data with receivers in both boreholes, eliminating the need for downhole sources. The obtained virtual crosswell containing direct waves, as well as P-P and P-SV reflections, enable constructing a velocity model and imaging the structure between wells.

The effective multiplicity of infection for HCMV depends on activity of the cellular 20S proteasome.

HCMV infection and reactivation continues to contribute to morbidity and mortality around the world. Antiviral compounds are available but have limitations. Here, we have defined the impact of the proteasome inhibitor bortezomib on HCMV replication. Proteasomal activities play a critical role in temporal changes required for replication. We demonstrate that disrupting these activities inhibits viral replication while likely supporting increased antiviral activity of the anti-HCMV agent, maribavir. Using a combination of live cell imaging and computational tools, we discover that a subset of infected cells progresses to fulminant infection which we define as the effective MOI, and this subset would otherwise be missed when analyzing the average of the population.

Transmission electron microscopy of epitaxial semiconductor materials and devices

Abstract The transmission electron microscope (TEM) is a powerful imaging, diffraction and spectroscopy tool that has revolutionized the field of microscopy. It has contributed to numerous breakthroughs in various scientific disciplines. TEM-based techniques can offer atomic resolution as well as elemental analysis, which benefit the study of epitaxial semiconductors and their related optoelectronic devices on the atomic scale. The design and optimization of the device performance depend on three key factors: the control of strain at nanometer scale, control of the formation and propagation of defects as well as the control of local electronic properties. Manipulation and optimization are only possible if the key factors can be characterized precisely. Herein, the TEM techniques for strain analysis, defect characterization and bandgap evaluation are reviewed and discussed. Lately, with the development of in-situ TEM techniques, researchers have been able to observe dynamic processes and study the behaviour of materials and devices under realistic conditions (in gaseous atmosphere or in liquids, at elevated or cryogenic temperatures, under strain, bias or illumination) in real-time with extremely high spatial resolution. This review explores the impact and significance of in-situ TEM in the field of semiconductors.

AI-Generated Annotations Dataset for Diverse Cancer Radiology Collections in NCI Image Data Commons

The National Cancer Institute (NCI) Image Data Commons (IDC) offers publicly available cancer radiology collections for cloud computing, crucial for developing advanced imaging tools and algorithms. Despite their potential, these collections are minimally annotated; only 4% of DICOM studies in collections considered in the project had existing segmentation annotations. This project increases the quantity of segmentations in various IDC collections. We produced high-quality, AI-generated imaging annotations dataset of tissues, organs, and/or cancers for 11 distinct IDC image collections. These collections contain images from a variety of modalities, including computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET). The collections cover various body parts, such as the chest, breast, kidneys, prostate, and liver. A portion of the AI annotations were reviewed and corrected by a radiologist to assess the performance of the AI models. Both the AI’s and the radiologist’s annotations were encoded in conformance to the Digital Imaging and Communications in Medicine (DICOM) standard, allowing for seamless integration into the IDC collections as third-party analysis collections. All the models, images and annotations are publicly accessible.

Application of nanoliposome as contrast agents for magnetic resonance imaging technique

AbstractLiposomes, nano‐sized vesicles primarily comprising phospholipids and cholesterol, have emerged as pivotal tools in medical imaging, notably in magnetic resonance imaging (MRI), due to their biocompatibility and ability to encapsulate diverse molecules. Tailorable properties like size, surface charge, and encapsulation capacity make liposomes ideal for targeted delivery of imaging agents and drugs to specific tissues, improving pharmacokinetics. As MRI contrast agent (CA) carriers, liposomes encapsulate gadolinium, mitigating toxicity and boosting relaxivity and circulation times. Functionalization with targeting ligands and stimuli‐responsive designs enhances their controlled release and targeted delivery capabilities, crucial for cancer imaging and therapy. Benefits include reduced toxicity, prolonged circulation, targeted delivery, enhanced bioavailability, and potential for multimodal imaging. Challenges remain, such as stability, clearance, and manufacturing intricacies, requiring further research. Nonetheless, liposomal MRI CAs hold promise for enhancing diagnostic precision and therapeutic effectiveness in oncology and neurology, offering a robust pathway for future biomedical advancements. Addressing existing limitations could unlock their full potential in improving patient care and outcomes.

Glutaraldehyde-enhanced autofluorescence as a general tool for 3D morphological imaging.

Routine histochemical techniques are capable of producing vast amount of information from diverse samples types, but these techniques are limited in their ability to generate 3D information. Autofluorescence imaging can be used to analyse samples in 3D but it suffers from weak/low signal intensities. Here, we describe a simple chemical treatment with glutaraldehyde to enhance autofluorescence for 3D fluorescence imaging and to generate detailed morphological images on whole-mount samples. This methodology is straightforward and cost-effective to implement, suitable for a wide range of organisms and sample types. Furthermore, it can be readily integrated with standard confocal and fluorescence microscopes for analysis. This approach has the potential to facilitate the analysis of biological 3D structures and research in developmental biology, including studies on model and non-model organisms.