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  1. Article ; Online: Automated Motion Correction for Myocardial Blood Flow Measurements and Diagnostic Performance of

    Kuronuma, Keiichiro / Wei, Chih-Chun / Singh, Ananya / Lemley, Mark / Hayes, Sean W / Otaki, Yuka / Hyun, Mark C / Van Kriekinge, Serge D / Kavanagh, Paul / Huang, Cathleen / Han, Donghee / Dey, Damini / Berman, Daniel S / Slomka, Piotr J

    Journal of nuclear medicine : official publication, Society of Nuclear Medicine

    2024  Volume 65, Issue 1, Page(s) 139–146

    Abstract: Motion correction (MC) affects myocardial blood flow (MBF) measurements ... ...

    Abstract Motion correction (MC) affects myocardial blood flow (MBF) measurements in
    MeSH term(s) Humans ; Coronary Circulation ; Myocardial Perfusion Imaging/methods ; Coronary Artery Disease/diagnostic imaging ; Coronary Angiography/methods ; Fractional Flow Reserve, Myocardial ; Positron-Emission Tomography/methods
    Language English
    Publishing date 2024-01-02
    Publishing country United States
    Document type Journal Article
    ZDB-ID 80272-4
    ISSN 1535-5667 ; 0097-9058 ; 0161-5505 ; 0022-3123
    ISSN (online) 1535-5667
    ISSN 0097-9058 ; 0161-5505 ; 0022-3123
    DOI 10.2967/jnumed.123.266208
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Downward myocardial creep during stress PET imaging is inversely associated with mortality.

    Kuronuma, Keiichiro / Miller, Robert J H / Wei, Chih-Chun / Singh, Ananya / Lemley, Mark H / Van Kriekinge, Serge D / Kavanagh, Paul B / Gransar, Heidi / Han, Donghee / Hayes, Sean W / Thomson, Louise / Dey, Damini / Friedman, John D / Berman, Daniel S / Slomka, Piotr J

    European journal of nuclear medicine and molecular imaging

    2024  Volume 51, Issue 6, Page(s) 1622–1631

    Abstract: Purpose: The myocardial creep is a phenomenon in which the heart moves from its original position during stress-dynamic PET myocardial perfusion imaging (MPI) that can confound myocardial blood flow measurements. Therefore, myocardial motion correction ... ...

    Abstract Purpose: The myocardial creep is a phenomenon in which the heart moves from its original position during stress-dynamic PET myocardial perfusion imaging (MPI) that can confound myocardial blood flow measurements. Therefore, myocardial motion correction is important to obtain reliable myocardial flow quantification. However, the clinical importance of the magnitude of myocardial creep has not been explored. We aimed to explore the prognostic value of myocardial creep quantified by an automated motion correction algorithm beyond traditional PET-MPI imaging variables.
    Methods: Consecutive patients undergoing regadenoson rest-stress [
    Results: A total of 4,276 patients (median age 71 years; 60% male) were analyzed, and 1,007 ACM events were documented during a 5-year median follow-up. Processing time for automatic motion correction was < 12 s per patient. Myocardial creep in the superior to inferior (downward) direction was greater than the other directions (median, 4.2 mm vs. 1.3-1.7 mm). Annual mortality rates adjusted for age and sex were reduced with a larger downward creep, with a 4.2-fold ratio between the first (0 mm motion) and 10th decile (11 mm motion) (mortality, 7.9% vs. 1.9%/year). Downward creep was associated with lower ACM after full adjustment for clinical and imaging parameters (adjusted hazard ratio, 0.93; 95%CI, 0.91-0.95; p < 0.001). Adding downward creep to the standard PET-MPI imaging model significantly improved ACM prediction (area under the receiver operating characteristics curve, 0.790 vs. 0.775; p < 0.001), but other directions did not (p > 0.5).
    Conclusions: Downward myocardial creep during regadenoson stress carries additional information for the prediction of ACM beyond conventional flow and perfusion PET-MPI. This novel imaging biomarker is quantified automatically and rapidly from stress dynamic PET-MPI.
    MeSH term(s) Humans ; Male ; Female ; Aged ; Myocardial Perfusion Imaging/methods ; Positron-Emission Tomography ; Heart/diagnostic imaging ; Middle Aged ; Myocardium/pathology ; Rubidium Radioisotopes ; Stress, Physiological ; Prognosis
    Chemical Substances Rubidium Radioisotopes
    Language English
    Publishing date 2024-01-23
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 8236-3
    ISSN 1619-7089 ; 0340-6997 ; 1619-7070
    ISSN (online) 1619-7089
    ISSN 0340-6997 ; 1619-7070
    DOI 10.1007/s00259-024-06611-2
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  3. Article ; Online: Improved myocardial blood flow estimation with residual activity correction and motion correction in

    Otaki, Yuka / Van Kriekinge, Serge D / Wei, Chih-Chun / Kavanagh, Paul / Singh, Ananya / Parekh, Tejas / Di Carli, Marcelo / Maddahi, Jamshid / Sitek, Arkadiusz / Buckley, Christopher / Berman, Daniel S / Slomka, Piotr J

    European journal of nuclear medicine and molecular imaging

    2021  Volume 49, Issue 6, Page(s) 1881–1893

    Abstract: Purpose: We sought to evaluate the diagnostic performance for coronary artery disease (CAD) of myocardial blood flow (MBF) quantification with : Methods: In total, 231 patients undergoing same-day pharmacologic rest and stress : Results: The area- ... ...

    Abstract Purpose: We sought to evaluate the diagnostic performance for coronary artery disease (CAD) of myocardial blood flow (MBF) quantification with
    Methods: In total, 231 patients undergoing same-day pharmacologic rest and stress
    Results: The area-under the receiver operating characteristics curve (AUC [95% confidence interval]) of stress MBF with MC/RAC was higher for minimal segment (0.89 [0.85-0.94]) than for minimal vessel (0.86 [0.81-0.92], p = 0.03) or global estimation (0.81 [0.75-0.87], p < 0.0001). The AUC of MFR with MC/RAC was higher for minimal segment (0.87 [0.81-0.93]) than for minimal vessel (0.83 [0.76-0.90], p = 0.014) or global estimation (0.77 [0.69-0.84], p < 0.0001). The AUCs of minimal segment stress MBF and MFR with MC/RAC were higher compared to those with no MC/RAC (p < 0.001 for both) or no MC/no RAC (p < 0.0001 for both).
    Conclusions: Minimal segment MBF or MFR estimation with MC and RAC improves the diagnostic performance for obstructive CAD compared to global assessment.
    MeSH term(s) Coronary Artery Disease/diagnostic imaging ; Coronary Circulation/physiology ; Fractional Flow Reserve, Myocardial ; Humans ; Myocardial Perfusion Imaging/methods ; Positron-Emission Tomography/methods
    Language English
    Publishing date 2021-12-30
    Publishing country Germany
    Document type Clinical Trial, Phase III ; Journal Article
    ZDB-ID 8236-3
    ISSN 1619-7089 ; 0340-6997 ; 1619-7070
    ISSN (online) 1619-7089
    ISSN 0340-6997 ; 1619-7070
    DOI 10.1007/s00259-021-05643-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Direct Risk Assessment From Myocardial Perfusion Imaging Using Explainable Deep Learning.

    Singh, Ananya / Miller, Robert J H / Otaki, Yuka / Kavanagh, Paul / Hauser, Michael T / Tzolos, Evangelos / Kwiecinski, Jacek / Van Kriekinge, Serge / Wei, Chih-Chun / Sharir, Tali / Einstein, Andrew J / Fish, Mathews B / Ruddy, Terrence D / Kaufmann, Philipp A / Sinusas, Albert J / Miller, Edward J / Bateman, Timothy M / Dorbala, Sharmila / Di Carli, Marcelo /
    Liang, Joanna X / Huang, Cathleen / Han, Donghee / Dey, Damini / Berman, Daniel S / Slomka, Piotr J

    JACC. Cardiovascular imaging

    2022  Volume 16, Issue 2, Page(s) 209–220

    Abstract: Background: Myocardial perfusion imaging (MPI) is frequently used to provide risk stratification, but methods to improve the accuracy of these predictions are needed.: Objectives: The authors developed an explainable deep learning (DL) model (HARD ... ...

    Abstract Background: Myocardial perfusion imaging (MPI) is frequently used to provide risk stratification, but methods to improve the accuracy of these predictions are needed.
    Objectives: The authors developed an explainable deep learning (DL) model (HARD MACE [major adverse cardiac events]-DL) for the prediction of death or nonfatal myocardial infarction (MI) and validated its performance in large internal and external testing groups.
    Methods: Patients undergoing single-photon emission computed tomography MPI were included, with 20,401 patients in the training and internal testing group (5 sites) and 9,019 in the external testing group (2 different sites). HARD MACE-DL uses myocardial perfusion, motion, thickening, and phase polar maps combined with age, sex, and cardiac volumes. The primary outcome was all-cause mortality or nonfatal MI. Prognostic accuracy was evaluated using area under the receiver-operating characteristic curve (AUC).
    Results: During internal testing, patients with normal perfusion and elevated HARD MACE-DL risk were at higher risk than patients with abnormal perfusion and low HARD MACE-DL risk (annualized event rate, 2.9% vs 1.2%; P < 0.001). Patients in the highest quartile of HARD MACE-DL score had an annual rate of death or MI (4.8%) 10-fold higher than patients in the lowest quartile (0.48% per year). In external testing, the AUC for HARD MACE-DL (0.73; 95% CI: 0.71-0.75) was higher than a logistic regression model (AUC: 0.70), stress total perfusion deficit (TPD) (AUC: 0.65), and ischemic TPD (AUC: 0.63; all P < 0.01). Calibration, a measure of how well predicted risk matches actual risk, was excellent in both groups (Brier score, 0.079 for internal and 0.070 for external).
    Conclusions: The DL model predicts death or MI directly from MPI, by estimating patient-level risk with good calibration and improved accuracy compared with traditional quantitative approaches. The model incorporates mechanisms to explain to the physician which image regions contribute to the adverse event prediction.
    MeSH term(s) Humans ; Deep Learning ; Myocardial Perfusion Imaging/methods ; Predictive Value of Tests ; Risk Assessment/methods ; Myocardial Infarction/diagnostic imaging ; Tomography, Emission-Computed, Single-Photon ; Prognosis ; Coronary Artery Disease/diagnostic imaging
    Language English
    Publishing date 2022-10-19
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2491503-8
    ISSN 1876-7591 ; 1936-878X
    ISSN (online) 1876-7591
    ISSN 1936-878X
    DOI 10.1016/j.jcmg.2022.07.017
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Signals of seminal vesicle autoantigen suppresses bovine serum albumin-induced capacitation in mouse sperm.

    Huang, Yen Hua / Kuo, Shin Peih / Lin, Mei Hsiang / Shih, Chwen Ming / Chu, Sin Tak / Wei, Chih Chun / Wu, Tasi Jung / Chen, Yee Hsiung

    Biochemical and biophysical research communications

    2005  Volume 338, Issue 3, Page(s) 1564–1571

    Abstract: Capacitation is the prerequisite process for sperm to gain the ability for successful fertilization. Unregulated capacitation will cause sperm to undergo a spontaneous acrosome reaction and then fail to fertilize an egg. Seminal plasma is thought to have ...

    Abstract Capacitation is the prerequisite process for sperm to gain the ability for successful fertilization. Unregulated capacitation will cause sperm to undergo a spontaneous acrosome reaction and then fail to fertilize an egg. Seminal plasma is thought to have the ability to suppress sperm capacitation. However, the mechanisms by which seminal proteins suppress capacitation have not been well understood. Recently, we demonstrated that a major seminal vesicle secretory protein, seminal vesicle autoantigen (SVA), is able to suppress bovine serum albumin (BSA)-induced mouse sperm capacitation. To further identify the mechanism of SVA action, we determine the molecular events associated with SVA suppression of BSA's activity. In this communication, we demonstrate that SVA suppresses the BSA-induced increase of intracellular calcium concentration ([Ca2+]i), intracellular pH (pH(i)), the cAMP level, PKA activity, protein tyrosine phosphorylation, and capacitation in mouse sperm. Besides, we also found that the suppression ability of SVA against BSA-induced protein tyrosine phosphorylation and capacitation could be reversed by dbcAMP (a cAMP agonist).
    MeSH term(s) Animals ; Autoantigens/metabolism ; Calcium/chemistry ; Calcium/metabolism ; Cations, Divalent/chemistry ; Cells, Cultured ; Cyclic AMP/metabolism ; Cyclic AMP-Dependent Protein Kinases/metabolism ; Hydrogen-Ion Concentration ; Male ; Mice ; Phosphotyrosine/metabolism ; Seminal Vesicle Secretory Proteins/metabolism ; Serum Albumin/pharmacology ; Signal Transduction/drug effects ; Sperm Capacitation/drug effects ; Sperm Capacitation/physiology ; Spermatozoa/drug effects ; Spermatozoa/metabolism ; Spermatozoa/physiology
    Chemical Substances Autoantigens ; Cations, Divalent ; Seminal Vesicle Secretory Proteins ; Serum Albumin ; seminal vesicle autoantigen ; Phosphotyrosine (21820-51-9) ; Cyclic AMP (E0399OZS9N) ; Cyclic AMP-Dependent Protein Kinases (EC 2.7.11.11) ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 2005-12-23
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 205723-2
    ISSN 0006-291X ; 0006-291X
    ISSN (online) 0006-291X
    ISSN 0006-291X
    DOI 10.1016/j.bbrc.2005.10.120
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  6. Article ; Online: Correlation among pathology, genetic and epigenetic profiles, and clinical outcome in oligodendroglial tumors.

    Kuo, Lu-Ting / Kuo, Kuang-Ting / Lee, Ming-Jang / Wei, Chih-Chun / Scaravilli, Francesco / Tsai, Jui-Chang / Tseng, Ham-Min / Kuo, Meng-Fai / Tu, Yong-Kwang

    International journal of cancer

    2009  Volume 124, Issue 12, Page(s) 2872–2879

    Abstract: Recent studies have revealed a correlation between specific genetic changes, such as loss of chromosome 1p and 19q, and sensitivity of oligodendroglial neoplasm to radiotherapy and chemotherapy; epigenetic changes also play an important role in some ... ...

    Abstract Recent studies have revealed a correlation between specific genetic changes, such as loss of chromosome 1p and 19q, and sensitivity of oligodendroglial neoplasm to radiotherapy and chemotherapy; epigenetic changes also play an important role in some tumors. In this retrospective study, we analyzed chromosomal alterations in 17 loci and promoter methylation status of 8 tumor-related genes in 49 oligodendroglial tumors (29 WHO grade II and 11 WHO grade III oligodendrogliomas; 7 WHO grade II and 2 WHO grade III oligoastrocytomas) using quantitative microsatellite analysis and methylation-specific polymerase chain reaction and correlated this information with clinical data. We also performed immunohistochemical stains for Ki-67 and O (6)-methyl guanine-DNA methyl transferase. Our results showed that the frequency of deletions in regions on 1p, 9p, 10q, 17p and 19q were 71.4%, 26.5%, 6.1%, 69.4% and 89.8%, respectively. Promoter methylation was detected in p14, p15, p16, p53, p73, PTEN, MGMT and RASSF1A genes in 24.5%, 6.1%, 46.9%, 0%, 6.1%, 42.9%, 53.1% and 77.6% of tumors, respectively. Statistical analysis identified that 9p22 loss, p73 methylation and p15 methylation were independently associated with reduced overall survival, and Ki-67 labeling index (LI) > or = 5%, 9p22 loss, no loss of 19q, p73 methylation, p14 methylation and unmethylated MGMT predicted shorter progression-free survival. Our findings suggest that the frequent deletion and hypermethylation of tumor-related genes may represent a mechanism of tumor development and progression and emphasize the importance of defining new molecular markers for predicting prognosis, tumor recurrence and therapeutic response in cancer management.
    MeSH term(s) Adolescent ; Adult ; Aged ; Aged, 80 and over ; Brain Neoplasms/genetics ; Brain Neoplasms/pathology ; Cell Proliferation ; Child ; Child, Preschool ; Chromosome Aberrations ; Chromosomes, Human/genetics ; DNA Methylation ; DNA Modification Methylases/genetics ; DNA Modification Methylases/metabolism ; DNA Repair Enzymes/genetics ; DNA Repair Enzymes/metabolism ; DNA, Neoplasm/genetics ; Epigenesis, Genetic ; Female ; Humans ; Immunoenzyme Techniques ; Ki-67 Antigen/metabolism ; Male ; Microsatellite Repeats ; Middle Aged ; Neoplasm Proteins/genetics ; Neoplasm Proteins/metabolism ; Neoplasm Staging ; Oligodendroglioma/genetics ; Oligodendroglioma/pathology ; Polymerase Chain Reaction ; Promoter Regions, Genetic/genetics ; Retrospective Studies ; Survival Rate ; Tumor Suppressor Proteins/genetics ; Tumor Suppressor Proteins/metabolism ; Ubiquitin-Protein Ligases/genetics ; Ubiquitin-Protein Ligases/metabolism ; Young Adult
    Chemical Substances DNA, Neoplasm ; Ki-67 Antigen ; Neoplasm Proteins ; Tumor Suppressor Proteins ; DNA Modification Methylases (EC 2.1.1.-) ; MGMT protein, human (EC 2.1.1.63) ; MIB1 ligase, human (EC 2.3.2.27) ; Ubiquitin-Protein Ligases (EC 2.3.2.27) ; DNA Repair Enzymes (EC 6.5.1.-)
    Language English
    Publishing date 2009-06-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 218257-9
    ISSN 1097-0215 ; 0020-7136
    ISSN (online) 1097-0215
    ISSN 0020-7136
    DOI 10.1002/ijc.24303
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  7. Article: Localization and characterization of an orphan receptor, guanylyl cyclase-G, in mouse testis and sperm.

    Huang, Yen-Hua / Wei, Chih-Chun / Su, Yueh-Hsing / Wu, Bo-Tsung / Ciou, Yi-Yun / Tu, Cheng-Fen / Cooper, Trevor G / Yeung, Ching-Hei / Chu, Sin-Tak / Tsai, Ming-Tzu / Yang, Ruey-Bing

    Endocrinology

    2006  Volume 147, Issue 10, Page(s) 4792–4800

    Abstract: We recently identified a novel testis-enriched receptor guanylyl cyclase (GC) in the mouse, designated mGC-G. To further investigate its protein expression and function, we generated a neutralizing antibody specifically against the extracellular domain ... ...

    Abstract We recently identified a novel testis-enriched receptor guanylyl cyclase (GC) in the mouse, designated mGC-G. To further investigate its protein expression and function, we generated a neutralizing antibody specifically against the extracellular domain of this receptor. RT-PCR and immunohistochemical analyses show that mGC-G is predominantly expressed from round spermatids to spermatozoa in mouse testis at both the mRNA and protein levels. Flow cytometry and confocal immunofluorescence reveal that mGC-G is a cell surface protein restricted to the plasma membrane overlying the acrosome and midpiece of the flagellum in mature sperm. Interestingly, Western blot analysis demonstrates that testicular mGC-G is approximately 180 kDa but is subject to limited proteolysis during epididymal sperm transport, resulting in a smaller fragment tethered on the mature sperm surface. On Fluo-3 cytometrical analysis and computer-assisted sperm assay, we found that serum albumin-induced elevation of sperm intracellular Ca(2+) concentration, protein tyrosine phosphorylation, and progressive motility associated with capacitation are markedly reduced by preincubation of the anti-mGC-G neutralizing antibody. Together, these results indicate that mGC-G is proteolytically modified in mature sperm membrane and suggest that mGC-G-mediated signaling may play a critical role in gamete/reproductive biology.
    MeSH term(s) Animals ; Antibodies, Blocking/pharmacology ; Blotting, Western ; Flow Cytometry ; Guanylate Cyclase/antagonists & inhibitors ; Guanylate Cyclase/genetics ; Guanylate Cyclase/physiology ; Immunoglobulins/metabolism ; Male ; Membrane Proteins/antagonists & inhibitors ; Membrane Proteins/genetics ; Membrane Proteins/physiology ; Mice ; Phosphorylation ; RNA, Messenger/biosynthesis ; Reverse Transcriptase Polymerase Chain Reaction ; Sperm Motility/physiology ; Spermatozoa/metabolism ; Testis/cytology ; Testis/metabolism ; Tyrosine/metabolism
    Chemical Substances Antibodies, Blocking ; Immunoglobulins ; Membrane Proteins ; RNA, Messenger ; Tyrosine (42HK56048U) ; GC-G protein, mouse (EC 4.6.1.2) ; Guanylate Cyclase (EC 4.6.1.2)
    Language English
    Publishing date 2006-10
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 427856-2
    ISSN 1945-7170 ; 0013-7227
    ISSN (online) 1945-7170
    ISSN 0013-7227
    DOI 10.1210/en.2005-1476
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