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1.
ACS Nano ; 18(11): 7677-7687, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38450654

ABSTRACT

Solid-state nanochannel-based sensing systems have been established as vigorous tools for sensing plentiful biomarkers due to their label-free, highly sensitive, and high-throughput screening. However, research on solid-state nanochannels has predominantly centered on the functional groups modified on the inner wall, neglecting investigations into the outer surface. Actually, the outer surface, as a part of the nanochannels, also plays a key role in regulating ionic current. When the target nears the entrance of the nanochannel and prepares to pass through, it would also interact with functional groups located on the nanochannel's outer surface, leading to subsequent alterations in the ionic current. Recently, the probes on the outer surface have experimentally demonstrated their ability to independently regulate ionic current, unveiling advantages in in situ target detection, especially for targets larger than the diameter of the nanochannels that cannot pass through them. Here, we review the progress over the past decade in nanochannels featuring diverse outer-surface functionalization aimed at enhanced sensing performance, including charge modification, wettability adjustment, and probe immobilization. In addition, we present the promises and challenges posed by outer-surface functionalized nanochannels and discuss possible directions for their future deployments.

2.
Insights Imaging ; 15(1): 77, 2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38499879

ABSTRACT

OBJECTIVE: To appraise the quality of guidelines on intravenous iodinated contrast media (ICM) use in patients with kidney disease, and to compare the recommendations among them. METHODS: We searched four literature databases, eight guideline libraries, and ten homepages of radiological societies to identify English and Chinese guidelines on intravenous ICM use in patients with kidney disease published between January 2018 and June 2023. The quality of the guidelines was assessed with the Scientific, Transparent, and Applicable Rankings (STAR) tool. RESULTS: Ten guidelines were included, with a median STAR score of 46.0 (range 28.5-61.5). The guidelines performed well in "Recommendations" domain (31/40, 78%), while poor in "Registry" (0/20, 0%) and "Protocol" domains (0/20, 0%). Nine guidelines recommended estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m2 as the cutoff for referring patients to discuss the risk-benefit balance of ICM administration. Three guidelines further suggested that patients with an eGFR < 45 mL/min/1.73 m2 and high-risk factors also need referring. Variable recommendations were seen in the acceptable time interval between renal function test and ICM administration, and that between scan and repeated scan. Nine guidelines recommended to use iso-osmolar or low-osmolar ICM, while no consensus has been reached for the dosing of ICM. Nine guidelines supported hydration after ICM use, but their protocols varied. Drugs or blood purification therapy were not recommended as preventative means. CONCLUSION: Guidelines on intravenous ICM use in patients with kidney disease have heterogeneous quality. The scientific societies may consider joint statements on controversial recommendations for variable timing and protocols. CRITICAL RELEVANCE STATEMENT: The heterogeneous quality of guidelines, and their controversial recommendations, leave gaps in workflow timing, dosing, and post-administration hydration protocols of contrast-enhanced CT scans for patients with kidney diseases, calling for more evidence to establish a safer and more practicable workflow. KEY POINTS: • Guidelines concerning iodinated contrast media use in kidney disease patients vary. • Controversy remains in workflow timing, contrast dosing, and post-administration hydration protocols. • Investigations are encouraged to establish a safer iodinated contrast media use workflow.

3.
Curr Cancer Drug Targets ; 24(6): 654-667, 2024.
Article in English | MEDLINE | ID: mdl-38419344

ABSTRACT

BACKGROUND: Lung adenocarcinoma (LUAD) is a major health challenge worldwide with an undesirable prognosis. LINC00982 has been implicated as a tumor suppressor in diverse human cancers; however, its role in LUAD has not been fully characterized. METHODS: Expression level and prognostic value of LINC00982 were investigated in pan-cancer and lung cancer from The Cancer Genome Atlas (TCGA) project. Differential expression analysis based on the LINC00982 expression level was performed in LUAD followed by gene set enrichment analysis (GSEA) and functional enrichment analyses. The association between LINC00982 expression and tumor immune microenvironment characteristics was evaluated. A potential ceRNA regulatory axis was identified and experimentally validated. RESULTS: We found that LINC00982 expression was downregulated and correlated with poor prognosis in LUAD. Enrichment analyses revealed that LINC00982 could inhibit DNA damage repair and cell proliferation, but enhance tumor metabolic reprogramming. We identified a competing endogenous RNA network involving LINC00982, miR-183-5p, and ATP-binding cassette subfamily A member 8 (ABCA8). Luciferase assays confirmed that miR-183-5p can interact with LINC00982 and ABCA8. Forced miR-183-5p expression reduced LINC00982 transcript levels and suppressed ABCA8 expression. CONCLUSIONS: Our findings revealed the LINC00982/miR-183-5p/ABCA8 axis as a potential therapeutic target in LUAD.


Subject(s)
ATP-Binding Cassette Transporters , Adenocarcinoma of Lung , Cell Proliferation , Computational Biology , Gene Expression Regulation, Neoplastic , Lung Neoplasms , MicroRNAs , RNA, Long Noncoding , Humans , MicroRNAs/genetics , RNA, Long Noncoding/genetics , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/pathology , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Lung Neoplasms/metabolism , ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/metabolism , Prognosis , Animals , Mice , Disease Progression , Tumor Microenvironment , Cell Line, Tumor , Mice, Nude
4.
BMC Med Res Methodol ; 23(1): 292, 2023 12 13.
Article in English | MEDLINE | ID: mdl-38093215

ABSTRACT

BACKGROUND: Complete reporting is essential for clinical research. However, the endorsement of reporting guidelines in radiological journals is still unclear. Further, as a field extensively utilizing artificial intelligence (AI), the adoption of both general and AI reporting guidelines would be necessary for enhancing quality and transparency of radiological research. This study aims to investigate the endorsement of general reporting guidelines and those for AI applications in medical imaging in radiological journals, and explore associated journal characteristic variables. METHODS: This meta-research study screened journals from the Radiology, Nuclear Medicine & Medical Imaging category, Science Citation Index Expanded of the 2022 Journal Citation Reports, and excluded journals not publishing original research, in non-English languages, and instructions for authors unavailable. The endorsement of fifteen general reporting guidelines and ten AI reporting guidelines was rated using a five-level tool: "active strong", "active weak", "passive moderate", "passive weak", and "none". The association between endorsement and journal characteristic variables was evaluated by logistic regression analysis. RESULTS: We included 117 journals. The top-five endorsed reporting guidelines were CONSORT (Consolidated Standards of Reporting Trials, 58.1%, 68/117), PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses, 54.7%, 64/117), STROBE (STrengthening the Reporting of Observational Studies in Epidemiology, 51.3%, 60/117), STARD (Standards for Reporting of Diagnostic Accuracy, 50.4%, 59/117), and ARRIVE (Animal Research Reporting of In Vivo Experiments, 35.9%, 42/117). The most implemented AI reporting guideline was CLAIM (Checklist for Artificial Intelligence in Medical Imaging, 1.7%, 2/117), while other nine AI reporting guidelines were not mentioned. The Journal Impact Factor quartile and publisher were associated with endorsement of reporting guidelines in radiological journals. CONCLUSIONS: The general reporting guideline endorsement was suboptimal in radiological journals. The implementation of reporting guidelines for AI applications in medical imaging was extremely low. Their adoption should be strengthened to facilitate quality and transparency of radiological study reporting.


Subject(s)
Artificial Intelligence , Periodicals as Topic , Humans , Checklist , Publishing , Reference Standards
5.
J Magn Reson Imaging ; 2023 Dec 19.
Article in English | MEDLINE | ID: mdl-38112305

ABSTRACT

BACKGROUND: Quantitative diffusion metrics provide additional microstructural information of diseases. The robustness of quantitative diffusion metrics should be established before clinical application. PURPOSE: To evaluate the variability and reproducibility of quantitative diffusion MRI metrics. STUDY TYPE: Prospective. POPULATION: 14 volunteers (7 men; median age, range, 28, 26-59 years). FIELD STRENGTH/SEQUENCE: 3.0-T/Diffusion spectrum imaging. ASSESSMENT: Brain MRI studies were performed four times per subject: involving different combinations of coil types and voxel sizes. Regions of interest of 13 brain anatomical sites were drawn by one observer twice and another observer once to allow interobserver and intraobserver reproducibility assessment. Twenty-five quantitative metrics were calculated using four diffusion models. STATISTICAL TESTS: The variability was evaluated with coefficients of variation (CV), and quartile coefficient of dispersion (QCD). The reproducibility was assessed with intraclass correlation coefficient (ICC), and concordance correlation coefficient (CCC). Wilcoxon signed rank test was used to compare the influence of factors on robustness of quantitative diffusion metrics. A two-tailed P < 0.05 was considered statistically significant. RESULTS: The variability of quantitative diffusion metrics showed CV of 2.4%-68.2%, and QCD of 0.6%-48.2%, respectively. The reproducibility of scans using 20-channel coils with voxels of 2 × 2 × 2 mm3 and 3 × 3 × 3 mm3 , respectively (ICC 0.03-0.84, CCC 0.03-0.84) was significantly worse than that of repeated scans using a 20-channel coil with a voxel size of 2 × 2 × 2 mm3 (ICC of 0.74-0.97, CCC 0.74-0.97) and that of scans using 20- and 64-channel coils, respectively, with a voxel size of 2 × 2 × 2 mm3 (ICC 0.59-0.95, CCC 0.59-0.95). The intraobserver reproducibility (ICC 0.49-0.94, CCC 0.49-0.94) was significantly better than the interobserver reproducibility (ICC 0.28-0.91, CCC 0.28-0.91). DATA CONCLUSION: Our study indicated that the voxel size has a greater influence on the reproducibility of quantitative diffusion metrics than scan-rescans and coils. The reproducibility within one observer was higher than that between two observers. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.

6.
Insights Imaging ; 14(1): 111, 2023 Jun 19.
Article in English | MEDLINE | ID: mdl-37336830

ABSTRACT

OBJECTIVE: To conduct an overview of meta-analyses of radiomics studies assessing their study quality and evidence level. METHODS: A systematical search was updated via peer-reviewed electronic databases, preprint servers, and systematic review protocol registers until 15 November 2022. Systematic reviews with meta-analysis of primary radiomics studies were included. Their reporting transparency, methodological quality, and risk of bias were assessed by PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) 2020 checklist, AMSTAR-2 (A MeaSurement Tool to Assess systematic Reviews, version 2) tool, and ROBIS (Risk Of Bias In Systematic reviews) tool, respectively. The evidence level supporting the radiomics for clinical use was rated. RESULTS: We identified 44 systematic reviews with meta-analyses on radiomics research. The mean ± standard deviation of PRISMA adherence rate was 65 ± 9%. The AMSTAR-2 tool rated 5 and 39 systematic reviews as low and critically low confidence, respectively. The ROBIS assessment resulted low, unclear and high risk in 5, 11, and 28 systematic reviews, respectively. We reperformed 53 meta-analyses in 38 included systematic reviews. There were 3, 7, and 43 meta-analyses rated as convincing, highly suggestive, and weak levels of evidence, respectively. The convincing level of evidence was rated in (1) T2-FLAIR radiomics for IDH-mutant vs IDH-wide type differentiation in low-grade glioma, (2) CT radiomics for COVID-19 vs other viral pneumonia differentiation, and (3) MRI radiomics for high-grade glioma vs brain metastasis differentiation. CONCLUSIONS: The systematic reviews on radiomics were with suboptimal quality. A limited number of radiomics approaches were supported by convincing level of evidence. CLINICAL RELEVANCE STATEMENT: The evidence supporting the clinical application of radiomics are insufficient, calling for researches translating radiomics from an academic tool to a practicable adjunct towards clinical deployment.

7.
J Orthop Surg Res ; 18(1): 414, 2023 Jun 07.
Article in English | MEDLINE | ID: mdl-37287036

ABSTRACT

PURPOSE: To systematically assess the quality of radiomics research in giant cell tumor of bone (GCTB) and to test the feasibility of analysis at the level of radiomics feature. METHODS: We searched PubMed, Embase, Web of Science, China National Knowledge Infrastructure, and Wanfang Data to identify articles of GCTB radiomics until 31 July 2022. The studies were assessed by radiomics quality score (RQS), transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) statement, checklist for artificial intelligence in medical imaging (CLAIM), and modified quality assessment of diagnostic accuracy studies (QUADAS-2) tool. The radiomic features selected for model development were documented. RESULTS: Nine articles were included. The average of the ideal percentage of RQS, the TRIPOD adherence rate and the CLAIM adherence rate were 26%, 56%, and 57%, respectively. The risk of bias and applicability concerns were mainly related to the index test. The shortness in external validation and open science were repeatedly emphasized. In GCTB radiomics models, the gray level co-occurrence matrix features (40%), first order features (28%), and gray-level run-length matrix features (18%) were most selected features out of all reported features. However, none of the individual feature has appeared repeatably in multiple studies. It is not possible to meta-analyze radiomics features at present. CONCLUSION: The quality of GCTB radiomics studies is suboptimal. The reporting of individual radiomics feature data is encouraged. The analysis at the level of radiomics feature has potential to generate more practicable evidence for translating radiomics into clinical application.


Subject(s)
Bone Neoplasms , Giant Cell Tumor of Bone , Humans , Artificial Intelligence , Giant Cell Tumor of Bone/diagnostic imaging , Diagnostic Imaging , Biomarkers , Bone Neoplasms/diagnostic imaging
8.
J Digit Imaging ; 36(4): 1390-1407, 2023 08.
Article in English | MEDLINE | ID: mdl-37071291

ABSTRACT

This study is aimed to evaluate effects of deep learning image reconstruction (DLIR) on image quality in single-energy CT (SECT) and dual-energy CT (DECT), in reference to adaptive statistical iterative reconstruction-V (ASIR-V). The Gammex 464 phantom was scanned in SECT and DECT modes at three dose levels (5, 10, and 20 mGy). Raw data were reconstructed using six algorithms: filtered back-projection (FBP), ASIR-V at 40% (AV-40) and 100% (AV-100) strength, and DLIR at low (DLIR-L), medium (DLIR-M), and high strength (DLIR-H), to generate SECT 120kVp images and DECT 120kVp-like images. Objective image quality metrics were computed, including noise power spectrum (NPS), task transfer function (TTF), and detectability index (d'). Subjective image quality evaluation, including image noise, texture, sharpness, overall quality, and low- and high-contrast detectability, was performed by six readers. DLIR-H reduced overall noise magnitudes from FBP by 55.2% in a more balanced way of low and high frequency ranges comparing to AV-40, and improved the TTF values at 50% for acrylic inserts by average percentages of 18.32%. Comparing to SECT 20 mGy AV-40 images, the DECT 10 mGy DLIR-H images showed 20.90% and 7.75% improvement in d' for the small-object high-contrast and large-object low-contrast tasks, respectively. Subjective evaluation showed higher image quality and better detectability. At 50% of the radiation dose level, DECT with DLIR-H yields a gain in objective detectability index compared to full-dose AV-40 SECT images used in daily practice.


Subject(s)
Deep Learning , Humans , Algorithms , Image Processing, Computer-Assisted , Phantoms, Imaging , Radiation Dosage , Tomography, X-Ray Computed , Radiographic Image Interpretation, Computer-Assisted
9.
Eur Radiol ; 33(8): 5331-5343, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36976337

ABSTRACT

OBJECTIVES: To evaluate image quality, diagnostic acceptability, and lesion conspicuity in abdominal dual-energy CT (DECT) using deep learning image reconstruction (DLIR) compared to those using adaptive statistical iterative reconstruction-V (Asir-V) at 50% blending (AV-50), and to identify potential factors impacting lesion conspicuity. METHODS: The portal-venous phase scans in abdominal DECT of 47 participants with 84 lesions were prospectively included. The raw data were reconstructed to virtual monoenergetic image (VMI) at 50 keV using filtered back-projection (FBP), AV-50, and DLIR at low (DLIR-L), medium (DLIR-M), and high strength (DLIR-H). A noise power spectrum (NPS) was generated. CT number and standard deviation values of eight anatomical sites were measured. Signal-to-noise (SNR), and contrast-to-noise ratio (CNR) values were calculated. Five radiologists assessed image quality in terms of image contrast, image noise, image sharpness, artificial sensation, and diagnostic acceptability, and evaluated the lesion conspicuity. RESULTS: DLIR further reduced image noise (p < 0.001) compared to AV-50 while better preserved the average NPS frequency (p < 0.001). DLIR maintained CT number values (p > 0.99) and improved SNR and CNR values compared to AV-50 (p < 0.001). DLIR-H and DLIR-M showed higher ratings in all image quality analyses than AV-50 (p < 0.001). DLIR-H provided significantly better lesion conspicuity than AV-50 and DLIR-M regardless of lesion size, relative CT attenuation to surrounding tissue, or clinical purpose (p < 0.05). CONCLUSIONS: DLIR-H could be safely recommended for routine low-keV VMI reconstruction in daily contrast-enhanced abdominal DECT to improve image quality, diagnostic acceptability, and lesion conspicuity. KEY POINTS: • DLIR is superior to AV-50 in noise reduction, with less shifts of the average spatial frequency of NPS towards low frequency, and larger improvements of NPS noise, noise peak, SNR, and CNR values. • DLIR-M and DLIR-H generate better image quality in terms of image contrast, noise, sharpness, artificial sensation, and diagnostic acceptability than AV-50, while DLIR-H provides better lesion conspicuity than AV-50 and DLIR-M. • DLIR-H could be safely recommended as a new standard for routine low-keV VMI reconstruction in contrast-enhanced abdominal DECT to provide better lesion conspicuity and better image quality than the standard AV-50.


Subject(s)
Deep Learning , Humans , Prospective Studies , Tomography, X-Ray Computed/methods , Image Processing, Computer-Assisted/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Algorithms , Radiation Dosage
10.
Eur Radiol ; 33(2): 1433-1444, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36018355

ABSTRACT

OBJECTIVE: To evaluate the study quality and clinical value of radiomics studies on chondrosarcoma. METHODS: PubMed, Embase, Web of Science, China National Knowledge Infrastructure, and Wanfang Data were searched for articles on radiomics for evaluating chondrosarcoma as of January 31, 2022. The study quality was assessed according to Radiomics Quality Score (RQS), Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) checklist, Image Biomarker Standardization Initiative (IBSI) guideline, and modified Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. The level of evidence supporting clinical use of radiomics on chondrosarcoma differential diagnosis was determined based on meta-analyses. RESULTS: Twelve articles were included. The median RQS was 10.5 (range, -3 to 15), with an adherence rate of 36%. The adherence rate was extremely low in domains of high-level evidence (0%), open science and data (17%), and imaging and segmentation (35%). The adherence rate of the TRIPOD checklist was 61%, and low for section of title and abstract (13%), introduction (42%), and results (56%). The reporting rate of pre-processing steps according to the IBSI guideline was 60%. The risk of bias and concern of application were mainly related to the index test. The meta-analysis on differential diagnosis of enchondromas vs. chondrosarcomas showed a diagnostic odds ratio of 43.90 (95% confidential interval, 25.33-76.10), which was rated as weak evidence. CONCLUSIONS: The current scientific and reporting quality of radiomics studies on chondrosarcoma was insufficient. Radiomics has potential in facilitating the optimization of operation decision-making in chondrosarcoma. KEY POINTS: • Among radiomics studies on chondrosarcoma, although differential diagnostic models showed promising performance, only pieces of weak level of evidence were reached with insufficient study quality. • Since the RQS rating, the TRIPOD checklist, and the IBSI guideline have largely overlapped with each other, it is necessary to establish one widely acceptable methodological and reporting guideline for radiomics research. • The TRIPOD model typing, the phase classification of image mining studies, and the level of evidence category are useful tools to assess the gap between academic research and clinical application, although their modifications for radiomics studies are needed.


Subject(s)
Chondrosarcoma , Diagnostic Imaging , Humans , Prognosis , Biomarkers , Diagnosis, Differential , Chondrosarcoma/diagnostic imaging
11.
Insights Imaging ; 13(1): 139, 2022 Aug 20.
Article in English | MEDLINE | ID: mdl-35986798

ABSTRACT

BACKGROUND: Multiple tools have been applied to radiomics evaluation, while evidence rating tools for this field are still lacking. This study aims to assess the quality of pancreatitis radiomics research and test the feasibility of the evidence level rating tool. RESULTS: Thirty studies were included after a systematic search of pancreatitis radiomics studies until February 28, 2022, via five databases. Twenty-four studies employed radiomics for diagnostic purposes. The mean ± standard deviation of the adherence rate was 38.3 ± 13.3%, 61.3 ± 11.9%, and 37.1 ± 27.2% for the Radiomics Quality Score (RQS), the Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) checklist, and the Image Biomarker Standardization Initiative (IBSI) guideline for preprocessing steps, respectively. The median (range) of RQS was 7.0 (- 3.0 to 18.0). The risk of bias and application concerns were mainly related to the index test according to the modified Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. The meta-analysis on differential diagnosis of autoimmune pancreatitis versus pancreatic cancer by CT and mass-forming pancreatitis versus pancreatic cancer by MRI showed diagnostic odds ratios (95% confidence intervals) of, respectively, 189.63 (79.65-451.48) and 135.70 (36.17-509.13), both rated as weak evidence mainly due to the insufficient sample size. CONCLUSIONS: More research on prognosis of acute pancreatitis is encouraged. The current pancreatitis radiomics studies have insufficient quality and share common scientific disadvantages. The evidence level rating is feasible and necessary for bringing the field of radiomics from preclinical research area to clinical stage.

12.
Insights Imaging ; 13(1): 138, 2022 Aug 20.
Article in English | MEDLINE | ID: mdl-35986808

ABSTRACT

OBJECTIVE: To update the systematic review of radiomics in osteosarcoma. METHODS: PubMed, Embase, Web of Science, China National Knowledge Infrastructure, and Wanfang Data were searched to identify articles on osteosarcoma radiomics until May 15, 2022. The studies were assessed by Radiomics Quality Score (RQS), Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) statement, Checklist for Artificial Intelligence in Medical Imaging (CLAIM), and modified Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. The evidence supporting radiomics application for osteosarcoma was rated according to meta-analysis results. RESULTS: Twenty-nine articles were included. The average of the ideal percentage of RQS, the TRIPOD adherence rate and the CLAIM adherence rate were 29.2%, 59.2%, and 63.7%, respectively. RQS identified a radiomics-specific issue of phantom study. TRIPOD addressed deficiency in blindness of assessment. CLAIM and TRIPOD both pointed out shortness in missing data handling and sample size or power calculation. CLAIM identified extra disadvantages in data de-identification and failure analysis. External validation and open science were emphasized by all the above three tools. The risk of bias and applicability concerns were mainly related to the index test. The meta-analysis of radiomics predicting neoadjuvant chemotherapy response by MRI presented a diagnostic odds ratio (95% confidence interval) of 28.83 (10.27-80.95) on testing datasets and was rated as weak evidence. CONCLUSIONS: The quality of osteosarcoma radiomics studies is insufficient. More investigation is needed before using radiomics to optimize osteosarcoma treatment. CLAIM is recommended to guide the design and reporting of radiomics research.

13.
ACS Nano ; 16(6): 9572-9582, 2022 Jun 28.
Article in English | MEDLINE | ID: mdl-35679123

ABSTRACT

Engineering the reaction interface is necessary for advancing various electrocatalytic processes. However, most designed catalysts tend to be ineffective due to the inevitable structural reconstruction. Here we utilize that operando electrocatalysis variations (i.e., chalcogen leaching) manipulate the reactant interface toward amine electrooxidation. Taking chalcogen-doped Ni(OH)2 as an example, operando techniques uncover that chalcogens leach from the matrix and then adsorb on the surface of NiOOH as chalcogenates during the electrooxidation process. The charged chalcogenates will induce the local electric field that pushes the polar amines through the inner Helmholtz plane to enrich on the catalyst surface. Meanwhile, the polarization effect of chalcogenates and amines boost amino C-N bond activation for dehydrogenation into nitrile C≡N bonds. Under the promotion effect of surface-adsorbed chalcogenate ions, our catalysts display over 99.5% propionitrile selectivity at the low potential of 1.317 V with an ultrahigh current density. This finding highlights the use of operando changes of catalysts to rationally design efficient catalysts and further clarifies the underlying role of chalcogen atoms in the electrooxidation process.

14.
Eur Radiol ; 32(9): 6196-6206, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35364712

ABSTRACT

OBJECTIVES: To implement a pipeline to automatically segment the ROI and to use a nomogram integrating the MRI-based radiomics score and clinical variables to predict responses to neoadjuvant chemotherapy (NAC) in osteosarcoma patients. METHODS: A total of 144 osteosarcoma patients treated with NAC were separated into training (n = 101) and test (n = 43) groups. After normalisation, ROIs for the preoperative MRI were segmented by a deep learning segmentation model trained with nnU-Net by using two independent manual segmentations as labels. Radiomics features were extracted using automatically segmented ROIs. Feature selection was performed in the training dataset by five-fold cross-validation. The clinical, radiomics, and clinical-radiomics models were built using multiple machine learning methods with the same training dataset and validated with the same test dataset. The segmentation model was evaluated by the Dice coefficient. AUC and decision curve analysis (DCA) were employed to illustrate the model performance and clinical utility. RESULTS: 36/144 (25.0%) patients were pathological good responders (pGRs) to NAC, while 108/144 (75.0%) were non-pGRs. The segmentation model achieved a Dice coefficient of 0.869 on the test dataset. The clinical and radiomics models reached AUCs of 0.636 with a 95% confidence interval (CI) of 0.427-0.860 and 0.759 (95% CI, 0.589-0.937), respectively, in the test dataset. The clinical-radiomics nomogram demonstrated good discrimination, with an AUC of 0.793 (95% CI, 0.610-0.975), and accuracy of 79.1%. The DCA suggested the clinical utility of the nomogram. CONCLUSION: The automatic nomogram could be applied to aid radiologists in identifying pGRs to NAC. KEY POINTS: • The nnU-Net trained by manual labels enables the use of an automatic segmentation tool for ROI delineation of osteosarcoma. • A pipeline using automatic lesion segmentation and followed by a radiomics classifier could aid the evaluation of NAC response of osteosarcoma. • A predictive nomogram composed of clinical variables and MRI-based radiomics score provides support for individualised treatment planning.


Subject(s)
Bone Neoplasms , Deep Learning , Osteosarcoma , Bone Neoplasms/diagnostic imaging , Bone Neoplasms/drug therapy , Humans , Magnetic Resonance Imaging/methods , Neoadjuvant Therapy , Nomograms , Osteosarcoma/diagnostic imaging , Osteosarcoma/drug therapy , Retrospective Studies
15.
ACS Omega ; 6(40): 25996-26003, 2021 Oct 12.
Article in English | MEDLINE | ID: mdl-34660961

ABSTRACT

Graphene oxide (GO), a widespread load platform in many research studies based on its microstructures, is largely made from flake graphite by a strong oxidation method. However, the differences of GO products made from different flake graphites have received little attention. Here, five GO products made from five different flake graphites by the Hummers method are investigated. The results reveal the differences in microstructures of the five GOs concerned with the ratio of C-C sp2 structures to defects and the amount of oxygen-containing functional groups, which are further evidenced by their performances of quenching efficiencies by five DNA fluorescent probes. We demonstrated that the microstructural differences of GO products are transmitted from their parent flake graphites. Meanwhile, three kinds of parent flake graphites are proposed: (1) with large flakes and complete C-C sp2 structures, (2) with large flakes but defective C-C sp2 structures, and (3) with fine flakes but moderate C-C sp2 structures, in which the performance of GO made from (1) is the best while the GO made from (3) shows comparable to or even better performance than that made from (2). Our work gives a reminder for precisely choosing graphite in the preparation of GOs and the potential value of tremendous natural fine-flake graphites.

16.
Adv Mater ; 33(45): e2104615, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34553420

ABSTRACT

Biochemical sensing probes based on aggregation-induced-emission luminogens (AIEgens) are widely used in biological imaging and therapy, chemical sensing, and material sciences. However, it is still a great challenge to quantify the targets through fluorescence intensity of AIEgen probes due to their undesirable aggregations. Here, a PyTPA-ZGO probe with three lifetime signals for precise quantification of furin is constructed: the lifetime signal 1 and signal 2 comes from AIEgen PyTPA-P (τPn ) and inorganic nanoparticles Zn2 GeO4 :Mn2+ -NH2 (τZn ), respectively, while the lifetime signal 3 is marked as the composite dual-lifetime signal (CDLSn , C D L S n = τ Z n τ P n ). In contrast, the fluorescence intensity signal of PyTPA-P shows defectively quantitative performance. Furthermore, it is found that the CDLSn exhibits higher significant differences than the two other lifetime signals (τPn and τZn ) thanks to its wide range between the maximum and minimum signal values and small standard deviation. Therefore, CDLSn is further used to accurately identify cell subtypes based on the specific concentration of furin in each subtype. The lifetime criterion can realize precise quantification, and it should be a promising direction of AIEgen-based quantitative analysis in the future.


Subject(s)
Fluorescent Dyes/chemistry , Furin/analysis , Microscopy, Fluorescence , Cell Line, Tumor , Cell Survival/drug effects , Fluorescent Dyes/pharmacology , Germanium/chemistry , Humans , Oxides/chemistry , Peptides/chemistry
17.
Nat Protoc ; 16(9): 4201-4226, 2021 09.
Article in English | MEDLINE | ID: mdl-34321637

ABSTRACT

Solid-state nanochannels (SSNs) provide a promising approach for biosensing due to the confinement of molecules inside, their great mechanical strength and diversified surface chemical properties; however, until now, their sensitivity and specificity have not satisfied the practical requirements of sensing applications, especially in complex matrices, i.e., media of diverse constitutions. Here, we report a protocol to achieve explicit regional and functional division of functional elements at the outer surface (FEOS) and inner wall (FEIW) of SSNs, which offers a nanochannel-based sensing platform with enhanced specificity and sensitivity. The protocol starts with the fabrication and characterization of the distribution of FEOS and FEIW. Then, the evaluation of the contributions of FEOS and FEIW to ionic gating is described; the FEIW mainly regulate ionic gating, and the FEOS can produce a synergistic effect. Finally, hydrophobic or highly charged FEOS are applied to ward off interference molecules, non-target molecules that may affect the ionic signal of nanochannels, which decreases false signals and helps to achieve the highly specific ionic output in complex matrices. Compared with other methods currently available, this method will contribute to the fundamental understanding of substance transport in SSNs and provide high specificity and sensitivity in SSN-based analyses. The procedure takes 3-6 d to complete.


Subject(s)
Biosensing Techniques , Nanopores , Sensitivity and Specificity
19.
Nanoscale Adv ; 2(8): 3244-3251, 2020 Aug 11.
Article in English | MEDLINE | ID: mdl-36134279

ABSTRACT

The fabrication of a flexible thermoelectric generator (TEG) with both high power output and good flexibility has drawn considerable attention. Solution-processed inorganic nanocrystals have good processibility in interface to retain excellent electrical properties of nanocrystals and can be processed into thin films on a flexible substrate by an easy scale-up printing or coating method. However, a high-performance TEG device based on inorganic solution-processed materials also poses challenges when it comes to flexibility of the whole device. Herein, flexible planar TEG devices are fabricated by printing an ink mixture comprising solution-processed bismuth telluride (Bi2Te3) nanoplates with reduced-graphene oxide (rGO) nanosheets onto flexible polyimide substrates. The interface treatment by hot ethylenediamine and the appropriate amount of rGO contribute to the high electrical properties of the material. Also, when rGO nanosheets of 1% mass ratio are added, the optimum power output of the corresponding rGO/Bi2Te3 TEG device with six elements reaches ∼1.72 µW at a temperature difference of 20 K. Moreover, owing to the contribution from flexible rGO nanosheets, the suitable thickness of each element, and the artful connection of elements with a soft copper wire in the devices, the 1% rGO/Bi2Te3 TEG device was found to be robust, and its electrical resistance merely changes by 2% after bending 1000 cycles on 5 mm in bending. These inorganic-based TEGs with both high performance and good flexibility will promote the development of new generation energy devices in the field of flexible electronics.

20.
Angew Chem Int Ed Engl ; 58(23): 7783-7787, 2019 06 03.
Article in English | MEDLINE | ID: mdl-30985979

ABSTRACT

Although it is well known that the amazing iridescent colors of the cuticle of beetles reflect the intricate nanoscale organization of bio-fibers, artificial inorganic materials with comparable optical responses have not yet been synthesized from abiotic nanoscale building blocks. Such materials could find broad applications, including in circular polarizers, to generate circularly polarized luminescence, or in lasers. Herein, we describe a general method for the fabrication of biomimetic chiral photonic crystals by Langmuir-Schaefer assembly of colloidal inorganic nanowires. We not only reproduced the intricate helical structure and circularly polarized color reflection observed in beetles, but also achieved the highest chiroptical activity with a dissymmetry factor of -1.6 ever reported for chiral inorganic nanostructures. More importantly, the programmable structural control based on the precise interlayer arrangement endows us with unprecedented freedom to manipulate the optical activity of as-fabricated chiral photonic crystals.


Subject(s)
Biomimetics/methods , Circular Dichroism/instrumentation , Circular Dichroism/methods , Coleoptera/anatomy & histology , Nanoparticles/chemistry , Photons , Animals , Microscopy, Atomic Force/instrumentation , Microscopy, Atomic Force/methods , Microscopy, Electron, Scanning/instrumentation , Microscopy, Electron, Scanning/methods
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