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  • 1
    Online Resource
    Online Resource
    High‐resolution and high‐sensitivity PET for quantitative molecular imaging of the monoaminergic nuclei: A GATE simulation study
    Wiley ; 2022
    In:  Medical Physics Vol. 49, No. 7 ( 2022-07), p. 4430-4444
    Details
    In: Medical Physics, Wiley, Vol. 49, No. 7 ( 2022-07), p. 4430-4444
    Abstract: Quantitative in vivo molecular imaging of fine brain structures requires high‐spatial resolution and high‐sensitivity. Positron emission tomography (PET) is an attractive candidate to introduce molecular imaging into standard clinical care due to its highly targeted and versatile imaging capabilities based on the radiotracer being used. However, PET suffers from relatively poor spatial resolution compared to other clinical imaging modalities, which limits its ability to accurately quantify radiotracer uptake in brain regions and nuclei smaller than 3 mm in diameter. Here we introduce a new practical and cost‐effective high‐resolution and high‐sensitivity brain‐dedicated PET scanner, using our depth‐encoding Prism‐PET detector modules arranged in a conformal decagon geometry, to substantially reduce the partial volume effect and enable accurate radiotracer uptake quantification in small subcortical nuclei. Methods Two Prism‐PET brain scanner setups were proposed based on our 4‐to‐1 and 9‐to‐1 coupling of scintillators to readout pixels using  mm 3 and  mm 3 crystal columns, respectively. Monte Carlo simulations of our Prism‐PET scanners, Siemens Biograph Vision, and United Imaging EXPLORER were performed using Geant4 application for tomographic emission (GATE). National Electrical Manufacturers Association (NEMA) standard was followed for the evaluation of spatial resolution, sensitivity, and count‐rate performance. An ultra‐micro hot spot phantom was simulated for assessing image quality. A modified Zubal brain phantom was utilized for radiotracer imaging simulations of 5‐HT 1A receptors, which are abundant in the raphe nuclei (RN), and norepinephrine transporters, which are highly concentrated in the bilateral locus coeruleus (LC). Results The Prism‐PET brain scanner with 1.5 mm crystals is superior to that with 1 mm crystals as the former offers better depth‐of‐interaction (DOI) resolution, which is key to realizing compact and conformal PET scanner geometries. We achieved uniform 1.3 mm full‐width‐at‐half‐maximum (FWHM) spatial resolutions across the entire transaxial field‐of‐view (FOV), a NEMA sensitivity of 52.1 kcps/MBq, and a peak noise equivalent count rate (NECR) of 957.8 kcps at 25.2 kBq/mL using 450–650 keV energy window. Hot spot phantom results demonstrate that our scanner can resolve regions as small as 1.35 mm in diameter at both center and 10 cm away from the center of the transaixal FOV. Both 5‐HT 1A receptor and norepinephrine transporter brain simulations prove that our Prism‐PET scanner enables accurate quantification of radiotracer uptake in small brain regions, with a 1.8‐fold and 2.6‐fold improvement in the dorsal RN as well as a 3.2‐fold and 4.4‐fold improvement in the bilateral LC compared to the Biograph Vision and EXPLORER, respectively. Conclusions Based on our simulation results, the proposed high‐resolution and high‐sensitivity Prism‐PET brain scanner is a promising cost‐effective candidate to achieve quantitative molecular neuroimaging of small but important brain regions with PET clinically viable.
    Type of Medium: Online Resource
    ISSN: 0094-2405 , 2473-4209
    URL: Issue
    URL: Article
    DOI: 10.1002/mp.v49.7
    DOI: 10.1002/mp.15653
    Language: English
    Publisher: Wiley
    Publication Date: 2022
    detail.hit.zdb_id: 1466421-5
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  • 2
    Online Resource
    Online Resource
    Interleaved signal multiplexing readout in depth encoding Prism‐PET detectors
    Wiley ; 2023
    In:  Medical Physics Vol. 50, No. 7 ( 2023-07), p. 4234-4243
    Details
    In: Medical Physics, Wiley, Vol. 50, No. 7 ( 2023-07), p. 4234-4243
    Abstract: Given the large number of readout pixels in clinical positron emission tomography (PET) scanners, signal multiplexing is an indispensable feature to reduce scanner complexity, power consumption, heat output, and cost. Purpose In this paper, we introduce interleaved multiplexing (iMux) scheme that utilizes the characteristic light‐sharing pattern of depth‐encoding Prism‐PET detector modules with single‐ended readout. Methods In the iMux readout, four anodes from every other silicon photomultiplier (SiPM) pixels across rows and columns, which overlap with four distinct light guides, are connected to the same application‐specific integrated circuit (ASIC) channel. The 4‐to‐1 coupled Prism‐PET detector module was used which consisted of a 16 ×  16 array of 1.5 × 1.5 × 20 mm 3 lutetium yttrium oxyorthosilicate (LYSO) scintillator crystals coupled to an 8 × 8 array with 3 ×  3 mm 2 SiPM pixels. A deep learning‐based demultiplexing model was investigated to recover the encoded energy signals. Two different experiments were performed with non‐multiplexed and multiplexed readouts to evaluate the spatial, depth of interaction (DOI), and timing resolutions of our proposed iMux scheme. Results The measured flood histograms, using the decoded energy signals from our deep learning‐based demultiplexing architecture, achieved perfect crystal identification of events with negligible decoding error. The average energy, DOI, and timing resolutions were 9.6 ± 1.5%, 2.9 ± 0.9 mm, and 266 ± 19 ps for non‐multiplexed readout and 10.3 ± 1.6%, 2.8 ± 0.8 mm, and 311 ± 28 ps for multiplexed readout, respectively. Conclusions Our proposed iMux scheme improves on the already cost‐effective and high‐resolution Prism‐PET detector module and provides 16‐to‐1 crystal‐to‐readout multiplexing without appreciable performance degradation. Also, only four SiPM pixels are shorted together in the 8 ×  8 array to achieve 4‐to‐1 pixel‐to‐readout multiplexing, resulting in lower capacitance per multiplexed channel.
    Type of Medium: Online Resource
    ISSN: 0094-2405 , 2473-4209
    URL: Issue
    URL: Article
    DOI: 10.1002/mp.v50.7
    DOI: 10.1002/mp.16456
    Language: English
    Publisher: Wiley
    Publication Date: 2023
    detail.hit.zdb_id: 1466421-5
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  • 3
    Online Resource
    Online Resource
    A conformal TOF–DOI Prism‐PET prototype scanner for high‐resolution quantitative neuroimaging
    Wiley ; 2023
    In:  Medical Physics Vol. 50, No. 6 ( 2023-06), p. 3401-3417
    Details
    In: Medical Physics, Wiley, Vol. 50, No. 6 ( 2023-06), p. 3401-3417
    Abstract: Positron emission tomography (PET) has had a transformative impact on oncological and neurological applications. However, still much of PET's potential remains untapped with limitations primarily driven by low spatial resolution, which severely hampers accurate quantitative PET imaging via the partial volume effect (PVE). Purpose We present experimental results of a practical and cost‐effective ultra‐high resolution brain‐dedicated PET scanner, using our depth‐encoding Prism‐PET detectors arranged along a compact and conformal gantry, showing substantial reduction in PVE and accurate radiotracer uptake quantification in small regions. Methods The decagon‐shaped prototype scanner has a long diameter of 38.5 cm, a short diameter of 29.1 cm, and an axial field‐of‐view (FOV) of 25.5 mm with a single ring of 40 Prism‐PET detector modules. Each module comprises a 16 × 16 array of 1.5 × 1.5 × 20‐mm 3 lutetium yttrium oxyorthosillicate (LYSO) scintillator crystals coupled 4‐to‐1 to an 8 × 8 array of silicon photomultiplier (SiPM) pixels on one end and to a prismatoid light guide array on the opposite end. The scanner's performance was evaluated by measuring depth‐of‐interaction (DOI) resolution, energy resolution, timing resolution, spatial resolution, sensitivity, and image quality of ultra‐micro Derenzo and three‐dimensional (3D) Hoffman brain phantoms. Results The full width at half maximum (FWHM) DOI, energy, and timing resolutions of the scanner are 2.85 mm, 12.6%, and 271 ps, respectively. Not considering artifacts due to mechanical misalignment of detector blocks, the intrinsic spatial resolution is 0.89‐mm FWHM. Point source images reconstructed with 3D filtered back‐projection (FBP) show an average spatial resolution of 1.53‐mm FWHM across the entire FOV. The peak absolute sensitivity is 1.2% for an energy window of 400−650 keV. The ultra‐micro Derenzo phantom study demonstrates the highest reported spatial resolution performance for a human brain PET scanner with perfect reconstruction of 1.00‐mm diameter hot‐rods. Reconstructed images of customized Hoffman brain phantoms prove that Prism‐PET enables accurate radiotracer uptake quantification in small brain regions (2–3 mm). Conclusions Prism‐PET will substantially strengthen the utility of quantitative PET in neurology for early diagnosis of neurodegenerative diseases, and in neuro‐oncology for improved management of both primary and metastatic brain tumors.
    Type of Medium: Online Resource
    ISSN: 0094-2405 , 2473-4209
    URL: Issue
    URL: Article
    DOI: 10.1002/mp.v50.6
    DOI: 10.1002/mp.16223
    Language: English
    Publisher: Wiley
    Publication Date: 2023
    detail.hit.zdb_id: 1466421-5
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  • 4
    Online Resource
    Online Resource
    Association of Serum Bile Acids Profile and Pathway Dysregulation With the Risk of Developing Diabetes Among Normoglycemic Chinese Adults: Findings From the 4C Study
    American Diabetes Association ; 2021
    In:  Diabetes Care Vol. 44, No. 2 ( 2021-02-01), p. 499-510
    Details
    In: Diabetes Care, American Diabetes Association, Vol. 44, No. 2 ( 2021-02-01), p. 499-510
    Abstract: Comprehensive assessment of serum bile acids (BAs) aberrations before diabetes onset remains inconclusive. We examined the association of serum BA profile and coregulation with the risk of developing type 2 diabetes mellitus (T2DM) among normoglycemic Chinese adults. RESEARCH DESIGN AND METHODS We tested 23 serum BA species in subjects with incident diabetes (n = 1,707) and control subjects (n = 1,707) matched by propensity score (including age, sex, BMI, and fasting glucose) from the China Cardiometabolic Disease and Cancer Cohort (4C) Study, which was composed of 54,807 normoglycemic Chinese adults with a median follow-up of 3.03 years. Multivariable-adjusted odds ratios (ORs) for associations of BAs with T2DM were estimated using conditional logistic regression. RESULTS In multivariable-adjusted logistic regression analysis, per SD increment of unconjugated primary and secondary BAs were inversely associated with incident diabetes, with an OR (95% CI) of 0.89 (0.83–0.96) for cholic acid, 0.90 (0.84–0.97) for chenodeoxycholic acid, and 0.90 (0.83–0.96) for deoxycholic acid (P & lt; 0.05 and false discovery rate & lt;0.05). On the other hand, conjugated primary BAs (glycocholic acid, taurocholic acid, glycochenodeoxycholic acid, taurochenodeoxycholic acid, and sulfated glycochenodeoxycholic acid) and secondary BA (tauroursodeoxycholic acid) were positively related with incident diabetes, with ORs ranging from 1.11 to 1.19 (95% CIs ranging between 1.05 and 1.28). In a fully adjusted model additionally adjusted for liver enzymes, HDL cholesterol, diet, 2-h postload glucose, HOMA-insulin resistance, and waist circumference, the risk estimates were similar. Differential correlation network analysis revealed that perturbations in intraclass (i.e., primary and secondary) and interclass (i.e., unconjugated and conjugated) BA coregulation preexisted before diabetes onset. CONCLUSIONS These findings reveal novel changes in BAs exist before incident T2DM and support a potential role of BA metabolism in the pathogenesis of diabetes.
    Type of Medium: Online Resource
    ISSN: 0149-5992 , 1935-5548
    URL: Article
    DOI: 10.2337/dc20-0884
    Language: English
    Publisher: American Diabetes Association
    Publication Date: 2021
    detail.hit.zdb_id: 1490520-6
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  • 5
    Online Resource
    Online Resource
    Amino acids, microbiota-related metabolites, and the risk of incident diabetes among normoglycemic Chinese adults: Findings from the 4C study
    Elsevier BV ; 2022
    In:  Cell Reports Medicine Vol. 3, No. 9 ( 2022-09), p. 100727-
    Details
    In: Cell Reports Medicine, Elsevier BV, Vol. 3, No. 9 ( 2022-09), p. 100727-
    Type of Medium: Online Resource
    ISSN: 2666-3791
    URL: Article
    DOI: 10.1016/j.xcrm.2022.100727
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2022
    detail.hit.zdb_id: 3019420-9
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  • 6
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    Online Resource
    A CRISPR/Cas12a-based platform for rapid on-site bovine viral diarrhea virus diagnostics
    Elsevier BV ; 2024
    In:  Journal of Integrative Agriculture ( 2024-3)
    Details
    In: Journal of Integrative Agriculture, Elsevier BV, ( 2024-3)
    Type of Medium: Online Resource
    ISSN: 2095-3119
    URL: Article
    DOI: 10.1016/j.jia.2024.03.074
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2024
    detail.hit.zdb_id: 2668746-X
    SSG: 21
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  • 7
    Online Resource
    Online Resource
    Gut microbiome and serum metabolome alterations in obesity and after weight-loss intervention
    Springer Science and Business Media LLC ; 2017
    In:  Nature Medicine Vol. 23, No. 7 ( 2017-7), p. 859-868
    Details
    In: Nature Medicine, Springer Science and Business Media LLC, Vol. 23, No. 7 ( 2017-7), p. 859-868
    Type of Medium: Online Resource
    ISSN: 1078-8956 , 1546-170X
    URL: Article
    DOI: 10.1038/nm.4358
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2017
    detail.hit.zdb_id: 1484517-9
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  • 8
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    Online Resource
    Postoperative Radiotherapy in Pathological T2–3N0M0 Thoracic Esophageal Squamous Cell Carcinoma: Interim Report of a Prospective, Phase III, Randomized Controlled Study
    Oxford University Press (OUP) ; 2020
    In:  The Oncologist Vol. 25, No. 4 ( 2020-04-01), p. e701-e708
    Details
    In: The Oncologist, Oxford University Press (OUP), Vol. 25, No. 4 ( 2020-04-01), p. e701-e708
    Abstract: The role of postoperative radiotherapy in pathological T2–3N0M0 esophageal squamous cell carcinoma is unknown. We aimed to evaluate the efficacy and safety of postoperative radiotherapy in patients with pathological T2–3N0M0 thoracic esophageal squamous cell carcinoma. Materials and Methods Patients aged 18–72 years with pathological stage T2–3N0M0 esophageal squamous cell carcinoma after radical surgery and without neoadjuvant therapy were eligible. Patients were randomly assigned to surgery alone or to receive postoperative radiotherapy of 50.4 Gy in supraclavicular field and 56 Gy in mediastinal field in 28 fractions over 6 weeks. The primary endpoint was disease-free survival. The secondary endpoints were local-regional recurrence rate, overall survival, and radiation-related toxicities. Results From October 2012 to February 2018, 167 patients were enrolled in this study. We analyzed 157 patients whose follow-up time was more than 1 year or who had died. The median follow-up time was 45.6 months. The 3-year disease-free survival rates were 75.1% (95% confidence interval [CI] 65.9–85.5) in the postoperative radiotherapy group and 58.7% (95% CI 48.2–71.5) in the surgery group (hazard ratio 0.53, 95% CI 0.30–0.94, p = .030). Local-regional recurrence rate decreased significantly in the radiotherapy group (10.0% vs. 32.5% in the surgery group, p = .001). The overall survival and distant metastasis rates were not significantly different between two groups. Grade 3 toxicity rate related to radiotherapy was 12.5%. Conclusion Postoperative radiotherapy significantly increased disease-free survival and decreased local regional recurrence rate in patients with pathological T2–3N0M0 thoracic esophageal squamous cell carcinoma with acceptable toxicities in this interim analysis. Further enrollment and follow-up are warranted to validate these findings in this ongoing trial.
    Type of Medium: Online Resource
    ISSN: 1083-7159 , 1549-490X
    URL: Article
    DOI: 10.1634/theoncologist.2019-0276
    Language: English
    Publisher: Oxford University Press (OUP)
    Publication Date: 2020
    detail.hit.zdb_id: 2023829-0
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  • 9
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    Online Resource
    Surface Functionalization of Micrometer Silver Flakes for Fabricating High-Performance Electrically Conductive Adhesives
    American Chemical Society (ACS) ; 2022
    In:  ACS Applied Electronic Materials Vol. 4, No. 11 ( 2022-11-22), p. 5387-5396
    Details
    In: ACS Applied Electronic Materials, American Chemical Society (ACS), Vol. 4, No. 11 ( 2022-11-22), p. 5387-5396
    Type of Medium: Online Resource
    ISSN: 2637-6113 , 2637-6113
    URL: Article
    DOI: 10.1021/acsaelm.2c01055
    Language: English
    Publisher: American Chemical Society (ACS)
    Publication Date: 2022
    detail.hit.zdb_id: 2949097-2
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  • 10
    Online Resource
    Online Resource
    Table4.DOCX
    Frontiers Media SA ; 2022
    In:  Frontiers in Cell and Developmental Biology Vol. 10 ( 2022-3-15)
    Details
    In: Frontiers in Cell and Developmental Biology, Frontiers Media SA, Vol. 10 ( 2022-3-15)
    Abstract: Purpose: Pituitary adenomas (PAs) are the second most common intracranial neoplasms. Total surgical resection was extremely important for curing PAs, whereas tumor stiffness has gradually become the most critical factor affecting the resection rate in PAs. We aimed to investigate the molecular mechanisms of tumor stiffening and explore novel medications to reduce stiffness for improving surgical remission rates in PA patients. Methods: RNA sequencing, whole-genome bisulfite sequencing, and whole exome sequencing were applied to identify transcriptomic, epigenomic, and genomic underpinnings among 11 soft and 11 stiff PA samples surgically resected from patients at Peking Union Medical College Hospital (PUMCH). GH3 cell line and xenograft PA model was used to demonstrate therapeutic effect of sunitinib, and atomic force microscopy (AFM) was used to detect the stiffness of tumors. Results: Tumor microenvironment analyses and immunofluorescence staining indicated endothelial cells (ECs) and cancer-associated fibroblasts (CAFs) were more abundant in stiff PAs. Weighted gene coexpression network analysis identified the most critical stiffness-related gene (SRG) module, which was highly correlated with stiff phenotype, ECs and CAFs. Functional annotations suggested SRGs might regulate PA stiffness by regulating the development, differentiation, and apoptosis of ECs and CAFs and related molecular pathways. Aberrant DNA methylation and m6A RNA modifications were investigated to play crucial roles in regulating PA stiffness. Somatic mutation analysis revealed increased intratumoral heterogeneity and decreased response to immunotherapy in stiff tumors. Connectivity Map analysis of SRGs and pRRophetic algorithm based on drug sensitivity data of cancer cell lines finally determine sunitinib as a promising agent targeting stiff tumors. Sunitinib inhibited PA growth in vitro and in vivo , and also reduced tumor stiffness in xenograft PA models detected by AFM. Conclusion: This is the first study investigating the underlying mechanisms contributing to the stiffening of PAs, and providing novel insights into medication therapy for stiff PAs.
    Type of Medium: Online Resource
    ISSN: 2296-634X
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    URL: Article
    DOI: 10.3389/fcell.2022.820562
    DOI: 10.3389/fcell.2022.820562.s001
    DOI: 10.3389/fcell.2022.820562.s002
    DOI: 10.3389/fcell.2022.820562.s003
    DOI: 10.3389/fcell.2022.820562.s004
    DOI: 10.3389/fcell.2022.820562.s005
    DOI: 10.3389/fcell.2022.820562.s006
    Language: Unknown
    Publisher: Frontiers Media SA
    Publication Date: 2022
    detail.hit.zdb_id: 2737824-X
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