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Bezzerides V, Yoshinaga D, Feng R, Prondzynski M, Shani K, Tharani Y, Mayourian J, Joseph M, Walker D, Bortolin R, Carreon C, Boss B, Upton S, Parker K, Pu W. Dysregulation of N-terminal acetylation causes cardiac arrhythmia and cardiomyopathy. RESEARCH SQUARE 2024:rs.3.rs-3398860. [PMID: 39070617 PMCID: PMC11275982 DOI: 10.21203/rs.3.rs-3398860/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
N-terminal-acetyltransferases including NAA10 catalyze N-terminal acetylation (Nt-acetylation), an evolutionarily conserved co-translational modification. Little is known about the role of Nt-acetylation in cardiac homeostasis. To gain insights, we studied a novel NAA10 variant (p.R4S) segregating with QT-prolongation, cardiomyopathy and developmental delay in a large kindred. Here we show that the NAA10-R4S mutation reduced enzymatic activity, decreased expression levels of NAA10/NAA15 proteins, and destabilized the enzymatic complex NatA. In NAA10R4S/Y-iPSC-CMs, dysregulation of the late sodium and slow rectifying potassium currents caused severe repolarization abnormalities, consistent with clinical QT prolongation. Engineered heart tissues generated from NAA10R4S/Y-iPSC-CMs had significantly decreased contractile force and sarcomeric disorganization, consistent with the pedigree's cardiomyopathic phenotype. We identified small molecule and genetic therapies that normalized the phenotype of NAA10R4S/Y-iPSC-CMs. Our study defines novel roles of Nt-acetylation in cardiac regulation and delineates mechanisms underlying QT prolongation, arrhythmia, and cardiomyopathy caused by NAA10 dysfunction.
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Parker K, Bollis NE, Ryzhov V. Ion-molecule reactions of mass-selected ions. MASS SPECTROMETRY REVIEWS 2024; 43:47-89. [PMID: 36447431 DOI: 10.1002/mas.21819] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Gas-phase reactions of mass-selected ions with neutrals covers a very broad area of fundamental and applied mass spectrometry (MS). Oftentimes, ion-molecule reactions (IMR) can serve as a viable alternative to collision-induced dissociation and other ion dissociation techniques when using tandem MS. This review focuses on the literature pertaining applications of IMR since 2013. During the past decade considerable efforts have been made in analytical applications of IMR, including advances in one of the major techniques for characterization of unsaturated fatty acids and lipids, ozone-induced dissociation, and the development of a new technique for sequencing of large ions, hydrogen atom attachment/abstraction dissociation. Many advances have also been made in identifying gas-phase chemistry specific to a functional group in organic and biological compounds, which are useful in structure elucidation of analytes and differentiation of isomers/isobars. With "soft" ionization techniques like electrospray ionization having become mainstream for quite some time now, the efforts in the area of metal ion catalysis have firmly moved into exploring chemistry of ligated metal complexes in their "natural" oxidation states allowing to model individual steps of mechanisms in homogeneous catalysis, especially in combination with high-level DFT calculations. Finally, IMR continue to contribute to the body of knowledge in the area of chemistry of interstellar processes.
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Khaledyan D, Marini TJ, M. Baran T, O’Connell A, Parker K. Enhancing breast ultrasound segmentation through fine-tuning and optimization techniques: Sharp attention UNet. PLoS One 2023; 18:e0289195. [PMID: 38091358 PMCID: PMC10718429 DOI: 10.1371/journal.pone.0289195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 09/03/2023] [Indexed: 12/18/2023] Open
Abstract
Segmentation of breast ultrasound images is a crucial and challenging task in computer-aided diagnosis systems. Accurately segmenting masses in benign and malignant cases and identifying regions with no mass is a primary objective in breast ultrasound image segmentation. Deep learning (DL) has emerged as a powerful tool in medical image segmentation, revolutionizing how medical professionals analyze and interpret complex imaging data. The UNet architecture is a highly regarded and widely used DL model in medical image segmentation. Its distinctive architectural design and exceptional performance have made it popular among researchers. With the increase in data and model complexity, optimization and fine-tuning models play a vital and more challenging role than before. This paper presents a comparative study evaluating the effect of image preprocessing and different optimization techniques and the importance of fine-tuning different UNet segmentation models for breast ultrasound images. Optimization and fine-tuning techniques have been applied to enhance the performance of UNet, Sharp UNet, and Attention UNet. Building upon this progress, we designed a novel approach by combining Sharp UNet and Attention UNet, known as Sharp Attention UNet. Our analysis yielded the following quantitative evaluation metrics for the Sharp Attention UNet: the Dice coefficient, specificity, sensitivity, and F1 score values obtained were 0.93, 0.99, 0.94, and 0.94, respectively. In addition, McNemar's statistical test was applied to assess significant differences between the approaches. Across a number of measures, our proposed model outperformed all other models, resulting in improved breast lesion segmentation.
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Khaledyan D, Marini TJ, O’Connell A, Parker K. Enhancing Breast Ultrasound Segmentation through Fine-tuning and Optimization Techniques: Sharp Attention UNet. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.14.549040. [PMID: 37503223 PMCID: PMC10370074 DOI: 10.1101/2023.07.14.549040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Segmentation of breast ultrasound images is a crucial and challenging task in computer-aided diagnosis systems. Accurately segmenting masses in benign and malignant cases and identifying regions with no mass is a primary objective in breast ultrasound image segmentation. Deep learning (DL) has emerged as a powerful tool in medical image segmentation, revolutionizing how medical professionals analyze and interpret complex imaging data. The UNet architecture is a highly regarded and widely used DL model in medical image segmentation. Its distinctive architectural design and exceptional performance have made it a popular choice among researchers in the medical image segmentation field. With the increase in data and model complexity, optimization and fine-tuning models play a vital and more challenging role than before. This paper presents a comparative study evaluating the effect of image preprocessing and different optimization techniques and the importance of fine-tuning different UNet segmentation models for breast ultrasound images. Optimization and fine-tuning techniques have been applied to enhance the performance of UNet, Sharp UNet, and Attention UNet. Building upon this progress, we designed a novel approach by combining Sharp UNet and Attention UNet, known as Sharp Attention UNet. Our analysis yielded the following quantitative evaluation metrics for the Sharp Attention UNet: the dice coefficient, specificity, sensitivity, and F1 score obtained values of 0.9283, 0.9936, 0.9426, and 0.9412, respectively. In addition, McNemar's statistical test was applied to assess significant differences between the approaches. Across a number of measures, our proposed model outperforms the earlier designed models and points towards improved breast lesion segmentation algorithms.
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Bashtawi M, Roberts N, Parker K, Alqhazo M. Concordance between admission and discharge diagnosis of a child and adolescent psychiatry inpatient unit. Minerva Pediatr (Torino) 2023:S2724-5276.23.07225-7. [PMID: 37335455 DOI: 10.23736/s2724-5276.23.07225-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/21/2023]
Abstract
BACKGROUND Psychiatry is arguably the most medical practice that is affected by culture. The pediatric literature is sparse with respect to the differences between child psychiatric units in different cultures and different countries. In this study, we aim to investigate the discordance between admission diagnosis and discharge diagnosis for child psychiatric disorders. METHODS A retrospective analysis was conducted on 206 patients admitted to a university hospital inpatient child and adolescent psychiatry unit in Ontario, Canada. The data extracted from electronic charts were age, gender, DSM-IV-based diagnosis at admission, living arrangement before admission, length of stay (minimum one day), post-discharge diagnosis, and post-discharge outcomes. RESULTS There was 75% agreement with the discharge diagnosis. We found strong negative and positive associations between conduct disorder at discharge and the prescription of antipsychotics (+), antidepressants (-), and stimulants (-), and there was a strong association between a conduct disorder (CD) diagnosis and medication-free status. The powerful effect size of stimulant medication was specific to the association between a primary diagnosis of ADHD (vs. not-ADHD) and stimulant medication (c2=127.5, df=1, phi=0.79, P<0.0001). CONCLUSIONS We have found a significant agreement between admission and discharge diagnosis. It is suggested that the inpatient stay helped to refine the formulation and to improve the child's well-being.
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Jess J, Yates B, Dulau-Florea A, Parker K, Inglefield J, Lichtenstein D, Schischlik F, Ongkeko M, Wang Y, Shahani S, Cullinane A, Smith H, Kane E, Little L, Chen D, Fry TJ, Shalabi H, Wang HW, Satpathy A, Lozier J, Shah NN. CD22 CAR T-cell associated hematologic toxicities, endothelial activation and relationship to neurotoxicity. J Immunother Cancer 2023; 11:e005898. [PMID: 37295816 PMCID: PMC10277551 DOI: 10.1136/jitc-2022-005898] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/23/2023] [Indexed: 06/12/2023] Open
Abstract
BACKGROUND Hematologic toxicities, including coagulopathy, endothelial activation, and cytopenias, with CD19-targeted chimeric antigen receptor (CAR) T-cell therapies correlate with cytokine release syndrome (CRS) and neurotoxicity severity, but little is known about the extended toxicity profiles of CAR T-cells targeting alternative antigens. This report characterizes hematologic toxicities seen following CD22 CAR T-cells and their relationship to CRS and neurotoxicity. METHODS We retrospectively characterized hematologic toxicities associated with CRS seen on a phase 1 study of anti-CD22 CAR T-cells for children and young adults with relapsed/refractory CD22+ hematologic malignancies. Additional analyses included correlation of hematologic toxicities with neurotoxicity and exploring effects of hemophagocytic lymphohistiocytosis-like toxicities (HLH) on bone marrow recovery and cytopenias. Coagulopathy was defined as evidence of bleeding or abnormal coagulation parameters. Hematologic toxicities were graded by Common Terminology Criteria for Adverse Events V.4.0. RESULTS Across 53 patients receiving CD22 CAR T-cells who experienced CRS, 43 (81.1%) patients achieved complete remission. Eighteen (34.0%) patients experienced coagulopathy, of whom 16 had clinical manifestations of mild bleeding (typically mucosal bleeding) which generally subsided following CRS resolution. Three had manifestations of thrombotic microangiopathy. Patients with coagulopathy had higher peak ferritin, D-dimer, prothrombin time, international normalized ratio (INR), lactate dehydrogenase (LDH), tissue factor, prothrombin fragment F1+2 and soluble vascular cell adhesion molecule-1 (s-VCAM-1). Despite a relatively higher incidence of HLH-like toxicities and endothelial activation, overall neurotoxicity was generally less severe than reported with CD19 CAR T-cells, prompting additional analysis to explore CD22 expression in the central nervous system (CNS). Single-cell analysis revealed that in contrast to CD19 expression, CD22 is not on oligodendrocyte precursor cells or on neurovascular cells but is seen on mature oligodendrocytes. Lastly, among those attaining CR, grade 3-4 neutropenia and thrombocytopenia were seen in 65% of patients at D28. CONCLUSION With rising incidence of CD19 negative relapse, CD22 CAR T-cells are increasingly important for the treatment of B-cell malignancies. In characterizing hematologic toxicities on CD22 CAR T-cells, we demonstrate that despite endothelial activation, coagulopathy, and cytopenias, neurotoxicity was relatively mild and that CD22 and CD19 expression in the CNS differed, providing one potential hypothesis for divergent neurotoxicity profiles. Systematic characterization of on-target off-tumor toxicities of novel CAR T-cell constructs will be vital as new antigens are targeted. TRIAL REGISTRATION NUMBER NCT02315612.
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Marini TJ, Castaneda B, Parker K, Baran TM, Romero S, Iyer R, Zhao YT, Hah Z, Park MH, Brennan G, Kan J, Meng S, Dozier A, O’Connell A. No sonographer, no radiologist: Assessing accuracy of artificial intelligence on breast ultrasound volume sweep imaging scans. PLOS DIGITAL HEALTH 2022; 1:e0000148. [PMID: 36812553 PMCID: PMC9931251 DOI: 10.1371/journal.pdig.0000148] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 10/21/2022] [Indexed: 05/12/2023]
Abstract
Breast ultrasound provides a first-line evaluation for breast masses, but the majority of the world lacks access to any form of diagnostic imaging. In this pilot study, we assessed the combination of artificial intelligence (Samsung S-Detect for Breast) with volume sweep imaging (VSI) ultrasound scans to evaluate the possibility of inexpensive, fully automated breast ultrasound acquisition and preliminary interpretation without an experienced sonographer or radiologist. This study was conducted using examinations from a curated data set from a previously published clinical study of breast VSI. Examinations in this data set were obtained by medical students without prior ultrasound experience who performed VSI using a portable Butterfly iQ ultrasound probe. Standard of care ultrasound exams were performed concurrently by an experienced sonographer using a high-end ultrasound machine. Expert-selected VSI images and standard of care images were input into S-Detect which output mass features and classification as "possibly benign" and "possibly malignant." Subsequent comparison of the S-Detect VSI report was made between 1) the standard of care ultrasound report by an expert radiologist, 2) the standard of care ultrasound S-Detect report, 3) the VSI report by an expert radiologist, and 4) the pathological diagnosis. There were 115 masses analyzed by S-Detect from the curated data set. There was substantial agreement of the S-Detect interpretation of VSI among cancers, cysts, fibroadenomas, and lipomas to the expert standard of care ultrasound report (Cohen's κ = 0.73 (0.57-0.9 95% CI), p<0.0001), the standard of care ultrasound S-Detect interpretation (Cohen's κ = 0.79 (0.65-0.94 95% CI), p<0.0001), the expert VSI ultrasound report (Cohen's κ = 0.73 (0.57-0.9 95% CI), p<0.0001), and the pathological diagnosis (Cohen's κ = 0.80 (0.64-0.95 95% CI), p<0.0001). All pathologically proven cancers (n = 20) were designated as "possibly malignant" by S-Detect with a sensitivity of 100% and specificity of 86%. Integration of artificial intelligence and VSI could allow both acquisition and interpretation of ultrasound images without a sonographer and radiologist. This approach holds potential for increasing access to ultrasound imaging and therefore improving outcomes related to breast cancer in low- and middle- income countries.
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Anderson J, Brittney D, Giang G, Smith A, Lee C, Parker K, Searcy H, Benner K, Limdi N, Guimbellot J. 263 Pharmacogenomics in people with cystic fibrosis: A personalized medicine approach. J Cyst Fibros 2022. [DOI: 10.1016/s1569-1993(22)00953-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Parker K, Honrath K, Rhee Y. Fruit and Vegetable Intakes Are Up, But Not Significantly, In College-Aged Young Adults During The COVID-19 Pandemic. J Acad Nutr Diet 2022. [PMCID: PMC9385434 DOI: 10.1016/j.jand.2022.06.203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Innes J, Miskelly C, Armstrong D, Fitzgerald N, Parker K, Stone Z. Movements and habitat connectivity of New Zealand forest birds: a review of available data. NEW ZEAL J ECOL 2022. [DOI: 10.20417/nzjecol.46.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Yim I, Parker K, Lim S. Pulmonary Artery Wave Intensity Analysis in Pulmonary Hypertension Due to Left Heart Disease. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Yim I, Parker K, Lim S. Reservoir Pressure Analysis in Group 2 Pulmonary Hypertension. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Ratneswaren A, Hadjiloizou N, Ahmad Y, Sen S, Maliq I, Parker K, Francis D, Hughes AD, Davies JE, Mayet J. Coronary haemodynamics associated with left ventricular hypertrophy in aortic stenosis and hypertension. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.1728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Left ventricular hypertrophy (LVH) occurs in both aortic stenosis (AS) and hypertension (HT) due to an increase in afterload. However, in AS there is an increase in resting coronary flow (per gram of LV) while in HT it is reduced.
Wave intensity analysis (WIA) is a well-established method of characterising and quantifying the energies that drive coronary flow. Energies propagating from the proximal vessel (aorta and systemic arteries) interact with energies travelling from the distal end (myocardial microcirculation). WIA allows the separation of these energies into the waves that drive cyclic changes in coronary flow.
Purpose
We aimed to compare coronary flow patterns in LVH secondary to AS with coronary flow patterns in LVH secondary to HT.
Methods
Thirty-one participants were recruited (mean age 63, 18 female), 10 with LVH and severe AS, 11 with LVH and HT, and 10 with no LVH and no AS. Participants underwent invasive pressure and Doppler velocity measurements in each of the left coronary arteries and echocardiography. We applied WIA.
Results
Mean resting coronary flow per gram of LV tissue (Fig. 1) was increased in participants with LVH secondary to AS (1.62±0.60 ml/min/g) and reduced in participants with LVH secondary to HT (0.49±0.27 ml/min/g), compared to participants with no LVH and no AS (1.47±0.73 ml/min/g).
We observed marked differences between the magnitudes of the waves driving coronary flow in the three groups (Fig. 2). Forward and backward travelling waves are shown above and below the line respectively. Waves causing acceleration of coronary forward flow are shown as black and waves causing deceleration are shown in white.
Wave 6, the backwards decompression wave (BDW), is particularly important for myocardial perfusion. The BDW corresponds to the diastolic 'suction' of blood down the coronary arteries during myocardial relaxation.
The energy of the BDW was increased in LVH secondary to AS (31.1x103 W m–2 s–2) but was reduced in LVH secondary to HT (12.3x103 W m–2 s–2) (p<0.05), compared to participants with no LVH and no AS (14.3x103 W m–2 s–2).
The energy of the BDW correlated with LV cavity pressure (r=0.84, p<0.001) and diastolic time (r=−0.62, p<0.001) only in LVH secondary to AS participants. In contrast, the BDW correlated with LV mass (r=−0.49, p=0.03) in participants with LVH secondary to HT and with no LVH and no AS, but not in participants with LVH secondary to AS.
Conclusions
In hypertension, LVH is associated with reduced mean coronary flow and reduced myocardial “suction” during diastole, presumably by the reduction in myocardial compliance associated with diastolic dysfunction.
However, in AS the large pressure gradient between the LV cavity and the aorta results in a large contractile force which is generated in systole and then released in diastole. This large diastolic force overwhelms any local impairment caused by the hypertrophied myocardium and contributes to high resting coronary flow in AS.
Funding Acknowledgement
Type of funding sources: None.
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Parker K, Weragoda GK, Mohr A, Canty AJ, O’Hair RAJ, Ryzhov V. Cracking and Dehydrogenation of Cyclohexane by [(phen)M(X)] + (M = Ni, Pd, Pt; X = H, CH 3) in the Gas Phase. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Parker K, Weragoda GK, Canty AJ, Ryzhov V, O’Hair RAJ. Modeling Metal-Catalyzed Polyethylene Depolymerization: [(Phen)Pd(X)] + (X = H and CH 3) Catalyze the Decomposition of Hexane into a Mixture of Alkenes via a Complex Reaction Network. Organometallics 2021. [DOI: 10.1021/acs.organomet.0c00782] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Hollenbach SJ, Thornburg LL, Feltovich H, Miller RK, Parker K, McAleavey S. 729 Placental elasticity imaging: location-informed interpretation may be required for disease state discrimination. Am J Obstet Gynecol 2021. [DOI: 10.1016/j.ajog.2020.12.752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Parker K, Weragoda GK, Canty AJ, Polyzos A, Ryzhov V, O’Hair RAJ. A Two-Step Catalytic Cycle for the Acceptorless Dehydrogenation of Ethane by Group 10 Metal Complexes: Role of the Metal in Reactivity and Selectivity. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00598] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Parker K, Weragoda GK, Pho V, Canty AJ, Polyzos A, O'Hair RAJ, Ryzhov V. Gas‐Phase Models for the Nickel‐ and Palladium‐Catalyzed Deoxygenation of Fatty Acids. ChemCatChem 2020. [DOI: 10.1002/cctc.202000908] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Comella A, Michail M, Cameron J, McCormick L, Gooley R, Parker K, Mathur A, Hughes A, Brown A, Cameron J. 895 The Immediate Physiological Impact of Transcatheter Aortic Valve Replacement on Central Aortic Pressure in Patients With Severe Aortic Stenosis. Heart Lung Circ 2020. [DOI: 10.1016/j.hlc.2020.09.902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Hollenbach SJ, Thornburg LL, Feltovich H, Miller RK, Parker K, McAleavey S. 266: Placental elasticity imaging demonstrates feasibility of an ultrasound-based method for generation of a placental biomarker. Am J Obstet Gynecol 2020. [DOI: 10.1016/j.ajog.2019.11.282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Hollenbach SJ, Baek J, Thornburg LL, Feltovich H, Miller RK, Parker K, McAleavey S. 1010: Placental H-scan sonography demonstrates feasibility of an ultrasound-based method for generation of a placental biomarker. Am J Obstet Gynecol 2020. [DOI: 10.1016/j.ajog.2019.11.1026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hollenbach SJ, Thornburg LL, Feltovich H, Miller RK, Parker K, McAleavey S. 1009: Elasticity imaging of placental tissue demonstrates potential for disease state discrimination. Am J Obstet Gynecol 2020. [DOI: 10.1016/j.ajog.2019.11.1025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Piacentino EL, Parker K, Gilbert TM, O'Hair RAJ, Ryzhov V. Role of Ligand in the Selective Production of Hydrogen from Formic Acid Catalysed by the Mononuclear Cationic Zinc Complexes [(L)Zn(H)] + (L=tpy, phen, and bpy). Chemistry 2019; 25:9959-9966. [PMID: 31090119 DOI: 10.1002/chem.201901360] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 04/25/2019] [Indexed: 11/10/2022]
Abstract
A series of zinc-based catalysts was evaluated for their efficiency in decomposing formic acid into molecular hydrogen and carbon dioxide in the gas phase using quadrupole ion trap mass spectrometry experiments. The effectiveness of the catalysts in the series [(L)Zn(H)]+ , where L=2,2':6',2''-terpyridine (tpy), 1,10-phenanthroline (phen) or 2,2'-bipyrydine (bpy), was found to depend on the ligand used, which turned out to be fundamental in tuning the catalytic properties of the zinc complex. Specifically, [(tpy)Zn(H)]+ displayed the fastest reaction with formic acid proceeding by dehydrogenation to produce the zinc formate complex [(tpy)Zn(O2 CH)]+ and H2 . The catalysts [(L)Zn(H)]+ are reformed by decarboxylating the zinc formate complexes [(L)Zn(O2 CH)]+ by collision-induced dissociation, which is the only reaction channel for each of the ligands used. The decarboxylation reaction was found to be reversible, since the zinc hydride complexes [(L)Zn(H)]+ react with carbon dioxide yielding the zinc formate complex. This reaction was again substantially faster for L=tpy than L=phen or bpy. The energetics and mechanisms of these processes were modelled using several levels of density functional theory (DFT) calculations. Experimental results are fully supported by the computational predictions.
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Piacentino EL, Rodriguez E, Parker K, Gilbert TM, O'Hair RAJ, Ryzhov V. Gas-phase functionalized carbon-carbon coupling reactions catalyzed by Ni (II) complexes. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:520-526. [PMID: 30989744 DOI: 10.1002/jms.4360] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 04/01/2019] [Accepted: 04/08/2019] [Indexed: 06/09/2023]
Abstract
Gas-phase C-C coupling reactions mediated by Ni (II) complexes were studied using a linear quadrupole ion trap mass spectrometer. Ternary nickel cationic carboxylate complexes, [(phen)Ni (OOCR1 )]+ (where phen = 1,10-phenanthroline), were formed by electrospray ionization. Upon collision-induced dissociation (CID), they extrude CO2 forming the organometallic cation [(phen)Ni(R1 )]+ , which undergoes gas-phase ion-molecule reactions (IMR) with acetate esters CH3 COOR2 to yield the acetate complex [(phen)Ni (OOCCH3 )]+ and a C-C coupling product R1 -R2 . These Ni(II)/phenanthroline-mediated coupling reactions can be performed with a variety of carbon substituents R1 and R2 (sp3 , sp2 , or aromatic), some of them functionalized. Reaction rates do not seem to be strongly dependent on the nature of the substituents, as sp3 -sp3 or sp2 -sp2 coupling reactions proceed rapidly. Experimental results are supported by density functional theory calculations, which provide insights into the energetics associated with the C-C bond coupling step.
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Boivin J, Koert E, Harris T, O'Shea L, Perryman A, Parker K, Harrison C. An experimental evaluation of the benefits and costs of providing fertility information to adolescents and emerging adults. Hum Reprod 2019; 33:1247-1253. [PMID: 29788136 PMCID: PMC6012744 DOI: 10.1093/humrep/dey107] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 05/02/2018] [Indexed: 12/14/2022] Open
Abstract
STUDY QUESTION Does the provision of fertility (compared to control) information affect fertility-related knowledge, perceived threat of infertility, anxiety, physical stress and fertility plans in adolescents and emerging adults? SUMMARY ANSWER The provision of fertility information was associated with increased fertility knowledge (emerging adults) and greater infertility threat (adolescents and emerging adults). WHAT IS KNOWN ALREADY According to fertility education research, adolescents and emerging adults know less than they should know about fertility topics. Fertility knowledge can be improved through the provision of information in older adults. STUDY DESIGN, SIZE, DURATION Experimental design. Secondary and university students completed pre-information questionnaires, were randomly assigned via computer to an experimental group, read either fertility (FertiEduc group) or healthy pregnancy information (Control group), and completed post-information questionnaires. Data were collected in group sessions via an online portal. PARTICIPANTS/MATERIALS, SETTING, METHODS Eligible participants were aged 16–18 (adolescents) or 21–24 years (emerging adults), childless, not currently pregnant (for men, partner not pregnant) or trying to conceive, presumed fertile and intending to have a child in the future. Of the 255 invited, 208 (n = 93 adolescents, n = 115 emerging adults) participated. The FertiEduc group received ‘A Guide to Fertility’, four online pages of information about fertility topics (e.g. ‘When are men and women most fertile?’) and the Control group received four online pages from the National Health Service (NHS) pregnancy booklet ‘Baby Bump and Beyond’. Participants completed a questionnaire (fertility knowledge, perceived threat of infertility, anxiety, physical stress and fertility plans, moderators) prior to and after the provision of information. Mixed factorial analysis of variance was used to examine the effects of information provision and hierarchical multiple regression to assess potential moderators of knowledge. MAIN RESULTS AND THE ROLE OF CHANCE The FertiEduc and Control groups were equivalent on age, gender, disability, relationship status and orientation at baseline. Results showed that fertility information significantly increased fertility knowledge for emerging adults only (P < 0.001) and threat of infertility for emerging adults and adolescents (P = 0.05). The moderators were not significant. Participation in the study was associated with an increase in feelings of anxiety but a decrease in physical stress reactions. Adolescents had more optimal fertility plans compared to emerging adults due to being younger. LIMITATIONS, REASONS FOR CAUTION This was an experimental study on a self-selected sample of men and women from selected educational institutions and only short term effects of information were studied. WIDER IMPLICATIONS OF THE FINDINGS Provision of fertility information can have benefits (increased fertility knowledge) but also costs (increase potential threat of infertility). Adolescents find fertility information positive but do not learn from it. Fertility education should be tailored according to age groups and created to minimise negative effects. Longitudinal examination of the effects of fertility information in multi-centre studies is warranted and should include measures of perceived threat of infertility. STUDY FUNDING/COMPETING INTEREST(S) Cardiff University funded this research. All authors have no conflicts of interest to declare.
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