Publications by authors named "Meixin Zhao"

Automatic anatomical localization is critical for radiology report generation. While many studies focus on lesion detection and segmentation, anatomical localization-accurately describing lesion positions in radiology reports-has received less attention. Conventional segmentation-based methods are limited to organ-level localization and often fail in severe disease cases due to low segmentation accuracy.

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Background: This study aims to explore the feasibility to automate the application process of nomograms in clinical medicine, demonstrated through the task of preoperative pleural invasion prediction in non-small cell lung cancer patients using PET/CT imaging.

Results: The automatic pipeline involves multimodal segmentation, feature extraction, and model prediction. It is validated on a cohort of 1116 patients from two medical centers.

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Objective: This study aims to develop and validate a PET/CT radiomics fusion model for preoperative predicting pleural invasion (PI) in non-small cell lung cancer (NSCLC) patients.

Methods: Data from Center A were divided into a training set (n = 260) and an internal validation set (n = 111), while data from Center B (n = 99) served as the external validation set. Radiomic features were extracted using PyRadiomics.

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Objective: Interim F-FDG PET/CT (iPET/CT) imaging demonstrates potential in assessing the early therapeutic response in lymphoma. Nevertheless, the prognostic significance of interim PET-CT in diffuse large B-cell lymphoma (DLBCL) remains controversial. This study aimed to evaluate whether semi-quantitative PET/CT metabolic parameters and other metrics could enhance the prognostic value of interim PET/CT in DLBCL patients exhibiting partial metabolic remission (PMR).

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Purpose: This study evaluates the value of [F]AlF-NOTA-FAPI-04PET/CT in assessing the disease activity of thyroid eye disease (TED).

Methods: Twenty-three TED patients and ten healthy controls were prospectively recruited and underwent [F]AlF-NOTA-FAPI-04 PET/CT scans. TED eyes were classified by Clinical Activity Score (CAS) as active (CAS +) or inactive (CAS-).

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Background: Pulmonary embolism (PE) is life-threatening and requires timely and accurate diagnosis, yet current imaging methods, like computed tomography pulmonary angiography, present limitations, particularly for patients with contraindications to iodinated contrast agents. We aimed to develop a quantitative texture analysis pipeline using machine learning (ML) based on non-contrast thoracic computed tomography (CT) scans to discover intensity and textural features correlated with regional lung perfusion (Q) physiology and pathology and synthesize voxel-wise Q surrogates to assist in PE diagnosis.

Methods: We retrospectively collected Tc-labeled macroaggregated albumin Q-SPECT/CT scans from patients suspected of PE, including an internal dataset of 76 patients (64 for training, 12 for testing) and an external testing dataset of 49 patients.

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Article Synopsis
  • The study aimed to assess how effective 18F-FDG PET/CT imaging is in diagnosing different stages of lung adenocarcinoma in infiltrative subsolid nodules and to identify predictive factors for invasive adenocarcinoma.
  • A retrospective analysis of 170 surgically confirmed lung adenocarcinoma cases revealed that characteristics like nodule size, spiculation, and metabolic parameters differed significantly across preinvasive, microinvasive, and invasive lesions.
  • Key predictive factors for invasive adenocarcinoma were found to be nodule composition, size, and maximum standardized uptake ratio, suggesting that specific imaging features could help in early diagnosis and intervention.*
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  • A new series of diphosphinoamine (PNP) ligands with -alkenyl groups were developed and used in a chromium-catalyzed process to selectively produce ethylene tri- and tetramers.
  • The performance of these ligands and the conditions for oligomerization significantly affected the catalytic activity and selectivity of the resulting products.
  • One ligand containing a cyclohexyl group achieved the highest activity of 2036 kg (g Cr h) with 81.1% selectivity for valuable compounds like 1-hexene and 1-octene under specific conditions of temperature and pressure.
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  • The study explores the use of immunohistochemical staining of PD-L1 in tumor biopsies to identify patients who could benefit from anti-PD-1 therapy, while noting the varied expression of PD-L1 in different cell types within tumors.
  • Researchers developed polymer-based lysosome-targeting chimeras (LYTACs) to selectively degrade PD-L1 on liver cancer cells without affecting host cells, using advanced PET imaging to track this process.
  • Findings indicate that PD-L1 expression on host cells is crucial for the effectiveness of anti-PD-1 therapy in liver cancer, suggesting that this novel LYTAC approach could improve our understanding of protein functions in various cell types in living subjects.
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Axially chiral biaryl δ-amino acids possess significantly different conformational properties and chiral environment from centrally chiral amino acids, therefore, have drawn considerable attention in the fields of synthetic and medicinal chemistry. Herein, a novel chiral phenanthroline-potassium catalyst has been developed by constructing a well-organized axially chiral ligand composed of one 1,10-phenanthroline unit and two axially chiral 1,1'-bi-2-naphthol (BINOL) units. In the presence of this catalyst, good to excellent yields and enantioselectivities (up to 99 % yield, 98 : 2 er) have been achieved in the ring-opening alcoholytic dynamic kinetic resolution of a variety of biaryl lactams, thereby providing an efficient protocol for catalytic asymmetric synthesis of unnatural axially chiral biaryl δ-amino acid derivatives.

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Organocatalyzed diastereo- and enantioselective [3 + 2] cycloaddition reactions of donor-acceptor (D-A) cyclopropanes with isatin-derived ketimines are presented. Different from well-developed Lewis acid activation protocols which promote the reactivity of D-A cyclopropanes through coordinating to the acceptor group, in this reaction, dicyanocyclopropylmethyl ketones can be activated through nucleophilic activation of the donor group by using dihydroquinine-derived squaramide as Brønsted base catalyst. The reaction affords functionalized spiro[oxindole-3,2'-pyrrolidines] with two nonadjacent tetra- and tri-substituted stereocenters in 83-99% yields, moderate to excellent diastereoselectivities (up to >20:1 diastereomeric ratio (dr)), and excellent enantioselectivities (up to >99% enantiomeric excess (ee)) under mild conditions.

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An Al 18F-prostate-specific membrane antigen (PSMA) Q PET/CT scan was performed in a 67-year-old man to identify any potential recurrent prostate cancer lesions, which revealed no recurrent or metastatic lesions. However, a large gallbladder stone with increased PSMA uptake was incidentally detected, which could be a potential pitfall in the interpretation of PSMA PET imaging.

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A 66-year-old man with gastric signet-ring cell carcinoma underwent both 18 F-FDG and 18 FAl-NOTA-FAPI PET/CT imaging. There was no abnormal FDG activity in the stomach, but there was diffuse intense 18 FAl-NOTA-FAPI uptake in the known lesion and an adjacent metastasis.

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Article Synopsis
  • Radiotherapy can stimulate a broader immune response that helps attack tumors not directly targeted by the treatment, known as the abscopal effect, with ICAM-1 being a crucial player in this process.
  • This study explores the role of ICAM-1 in activating and aiding CD8 T cells' function during immunotherapy combined with radiotherapy, using noninvasive imaging techniques to assess CD8 T cell activity.
  • The research identified a drug, VS-6063, which enhances the ability of CD8 T cells to fight tumors by improving their movement into tumors, and emphasizes the potential of imaging ICAM-1 to guide effective combination therapies in cancer treatment.
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Silk fibroin (SF)-based materials are characterized by their outstanding biocompatibility and biodegradability and are considered as the most promising candidates for next-generation flexible electronics. In order to generate such devices, SF can be mixed with carbon nanotubes (CNTs) which feature excellent mechanical, electrical, and thermal properties. However, obtaining regenerated SF with homogeneous dispersion of CNTs in a sustainable manner represents a challenging task, mainly due to the difficulty in overcoming van der Waals forces and strong π-π interactions that hold together the CNT structure.

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Molecular conformations induced by the rotation about single bonds play a crucial role in chemical transformations. Revealing the relationship between the conformations of chiral catalysts and the enantiodiscrimination is a formidable challenge due to the great difficulty in isolating the conformers. Herein, we report a chiral catalytic system composed of an achiral catalytically active unit and an axially chiral 1,1'-bi-2-naphthol (BINOL) unit which are connected via a C-O single bond.

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Objectives: This study investigates the ability of machine learning (ML) models trained on clinical data and 2-deoxy-2-[18F]fluoro-D-glucose(FDG) positron emission tomography/computed tomography (PET/CT) radiomics to predict overall survival (OS), tumor grade (TG), and histologic growth pattern risk (GPR) in lung adenocarcinoma (LUAD) patients.

Methods: A total of 421 treatment-naive patients with histologically-proven LUAD and available FDG PET/CT imaging were retrospectively included. Four cohorts were assessed for predicting 4-year OS (n = 276), 3-year OS (n = 280), TG (n = 298), and GPR (n = 265).

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Solitary tuberculoma of periaortic space is extremely rare. We report a case of periaortic tuberculous granuloma revealed by 18 F-FDG PET/CT in a 51-year-old woman without pulmonary or any other organ involvement. Awareness of this rare but possible atypical presentation of tuberculosis is helpful for the differential diagnosis of periaortic mass.

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Emulsion hydrogels are structurally composite materials combining the advantages of emulsions and hydrogels with the ability to accommodate hydrophobic and hydrophilic components in one system. It is a promising strategy for the excellent encapsulation and delivery of many bioactive ingredients. In this work, the thyme oil-loaded zwitterionic emulsion hydrogels are constructed by the cellulose acetoacetate-horseradish peroxidase-hydrogen peroxide-initiated (CAA-HRP-HO-initiated) ternary enzyme-mediated polymerization of the thyme oil-in-water (O/W) emulsions stabilized by cellulose acetoacetate (CAA).

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Duodenobiliary reflux is believed to be 1 of the causes of recurrent bacterial cholangitis. We reported a 65-year-old woman with intermittent epigastric pain for 20 years. She was diagnosed with cholelithiasis in the past, and she still had recurrent abdominal pain after the stone was removed.

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An efficient organocatalytic diastereo- and enantioselective formal [3 + 2] cycloaddition reaction of α-isocyanoacetates with saccharin-derived 1-azadienes catalyzed by a dihydroquinine derived squaramide catalyst has been investigated, and it furnished the corresponding directly linked benzo[d]isothiazole 1,1-dioxide-dihydropyrroles with two adjacent tertiary-quaternary stereocenters in high yields (up to 98%), with moderate to excellent stereoselectivities (up to >20 : 1 dr and 97% ee) under mild conditions.

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A catalytic asymmetric synthesis of 3,4-dihydrocoumarins with adjacent tertiary-quaternary stereocenters by 1,6-addition/transesterification cascade reaction of α-isocyanoacetates with ortho-hydroxyphenyl-substituted para-quinone methides (p-QMs) has been developed. Using a combination of dihydroquinidine-derived aminophosphine and silver nitrate as a binary catalytic system, moderate to good yields, excellent diastereoselectivities (>20 : 1 dr) and good to excellent enantioselectivities (up to 94% ee) were achieved for a wide range of isocyanoacetates and p-QMs.

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We reported herein an unexpected alkaloid-derived squaramide-catalyzed asymmetric two-component Ugi-type reaction of α-aryl-substituted isocyanoacetates with C,N-cyclic azomethine imines, which provides concise access to optically active C1-oxazole-substituted tetrahydroisoquinolines in good yields (86-93%) and high enantioselectivities (up to 98% enantiomeric excess) under mild conditions.

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In the era of rituximab, the International Prognostic Index (IPI) has been inefficient in initial risk stratification for patients with R-CHOP-treated diffuse large B-cell lymphoma (DLBCL). To estimate the predictive values of PET/CT quantitative parameters and three prognostic models consisting of baseline and interim parameters for three-year progression-free survival (PFS), we conducted an analysis of 85 patients in China with DLBCL underwent baseline and interim PET/CT scans and treated at the Department of Hematology of Peking University Third Hospital from November 2012 to November 2017. The PET/CT parameters, viz.

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An efficient organocatalytic asymmetric tandem conjugate addition-protonation of α-substituted isocyanoacetates to 2-chloroacrylonitrile catalyzed by dihydroquinine-derived thiourea has been investigated, affording the corresponding adducts with two non-adjacent tertiary-quaternary stereocenters in excellent yields (up to 99%) along with good to excellent diastereo- and enantioselectivities (up to 20 : 1 dr, up to 95% ee) under mild conditions. The adduct can also be transformed into chiral γ-lactam by synthetic transformations.

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