279 results on '"Powell, JA"'
Search Results
52. My special place
- Author
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Powell, Jacqui
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- 2005
53. Perspectives in practice. Maternal and child health nutrition training builds leadership skills.
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Letos SN, Trahms CM, Lucas B, and Powell JA
- Published
- 2001
- Full Text
- View/download PDF
54. CIB1 contributes to oncogenic signalling by Ras via modulating the subcellular localisation of sphingosine kinase 1
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Andrew Ruszkiewicz, Stuart M. Pitson, Jason A. Powell, Briony L. Gliddon, Wenying Zhu, T. Tin, Melissa R. Pitman, Paul A.B. Moretti, Leslie V. Parise, Joanna M. Woodcock, Kate E. Jarman, Zhu, W, Gliddon, BL, Jarman, KE, Moretti, PAB, Tin, T, Parise, LV, Woodcock, JM, Powell, JA, Ruszkiewicz, A, Pitman, MR, and Pitson, SM
- Subjects
0301 basic medicine ,Cancer Research ,Carcinogenesis ,Cell Survival ,sphingosine kinase 1 ,Biology ,medicine.disease_cause ,oncogenic signalling ,Article ,Proto-Oncogene Proteins p21(ras) ,03 medical and health sciences ,0302 clinical medicine ,Growth factor receptor ,Downregulation and upregulation ,Cell Line, Tumor ,Neoplasms ,Genetics ,medicine ,Humans ,Neoplastic transformation ,HRAS ,Molecular Biology ,Integrin binding ,Calcium-Binding Proteins ,Cell Membrane ,Cell biology ,CIB1 ,Gene Expression Regulation, Neoplastic ,Phosphotransferases (Alcohol Group Acceptor) ,030104 developmental biology ,Sphingosine kinase 1 ,sphingosine kinase ,030220 oncology & carcinogenesis ,Cancer research ,biology.protein ,Calcium ,Ectopic expression ,plasma membrane localisation ,Ras - Abstract
CIB1 (calcium and integrin binding protein 1) is a small intracellular protein with numerous interacting partners, and hence has been implicated in various cellular functions. Recent studies have revealed emerging roles of CIB1 in regulating cancer cell survival and angiogenesis, although the mechanisms involved have remained largely undefined. In investigating the oncogenic function of CIB1, we initially found that CIB1 is widely up-regulated across a diverse range of cancers, with this upregulation frequently correlating with oncogenic mutations of KRas. Consistent with this, we found that ectopic expression of oncogenic KRas and HRas in cells resulted in elevated CIB1 expression. We previously described the Ca2+-myristoyl switch function of CIB1, and its ability to facilitate agonist-induced plasma membrane localisation of sphingosine kinase 1 (SK1), a location where SK1 is known to elicit oncogenic signalling. Thus, we examined the role this may play in oncogenesis. Consistent with these findings, we demonstrated here that over-expression of CIB1 by itself is sufficient to drive localisation of SK1 to the plasma membrane and enhance the membrane-associated enzymatic activity of SK1, as well as its oncogenic signalling. We subsequently demonstrated that elevated levels of CIB1 resulted in full neoplastic transformation, in a manner dependent on SK1. In agreement with our previous findings that SK1 is a downstream mediator of oncogenic signalling by Ras, we found that targeting CIB1 also inhibited neoplastic growth of cells induced by oncogenic Ras, suggesting an important pro-tumorigenic role for CIB1. Thus, we have demonstrated for the first time a role for CIB1 in neoplastic transformation, and revealed a novel mechanism facilitating oncogenic signalling by Ras and SK1 Refereed/Peer-reviewed
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- 2017
55. Sustained inhibition of STAT5, but not JAK2, is essential for TKI-induced cell death in chronic myeloid leukemia
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Deborah L. White, E Nievergall, J A Powell, Timothy P. Hughes, Tamara M. Leclercq, L Schafranek, Devendra K Hiwase, Schafranek, L, Nievergall, E, Powell, JA, Hiwase, DK, Leclerq, T, Hughes, TP, and White, DL
- Subjects
Cancer Research ,Programmed cell death ,medicine.drug_class ,Blotting, Western ,Antigens, CD34 ,Apoptosis ,Genes, abl ,Biology ,Tyrosine-kinase inhibitor ,chronic myeloid leukemia ,Leukemia, Myelogenous, Chronic, BCR-ABL Positive ,hemic and lymphatic diseases ,STAT5 Transcription Factor ,medicine ,kinase inhibitors ,Humans ,apoptosia ,Progenitor cell ,Protein Kinase Inhibitors ,ABL ,Kinase ,Myeloid leukemia ,Hematology ,Janus Kinase 2 ,cell death ,Oncology ,Cancer research ,Janus kinase - Abstract
Kinase inhibitors block proliferative signals in BCR-ABL1+ leukemic cells, but their capacity to induce apoptosis is poorly understood. Initial studies suggested that very brief exposure to kinase inhibitors was sufficient to induce apoptosis in chronic myeloid leukemia (CML) cells. However, flaws in this experimental model have subsequently been identified, leading to the conclusion that apoptosis only occurs with sustained low-level kinase inhibition. Thus, the minimum duration of complete kinase inhibition required to commit CML cells to death is unknown. Here we confirm that
- Published
- 2014
56. Blocking cytokine signaling along with intense Bcr-Abl kinase inhibition induces apoptosis in primary CML progenitors
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Angel F. Lopez, Jason A. Powell, Timothy P. Hughes, L B To, Junia V. Melo, Devendra K Hiwase, Amity Frede, Stephanie Zrim, Deborah L. White, Sharad Kumar, Mark A. Guthridge, Richard J D'Andrea, Verity A Saunders, Hiwase, DK, White, DL, Powell, JA, Saunders, VA, Zrim, SA, Frede, AK, Guthridge, MA, Lopez, AF, D'Andrea, RJ, To, LB, Melo, JV, Kumar, S, and Hughes, TP
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Cancer Research ,medicine.drug_class ,medicine.medical_treatment ,Blotting, Western ,Dasatinib ,Fusion Proteins, bcr-abl ,Antigens, CD34 ,Apoptosis ,cell lines ,bone marrow diseases ,Biology ,Philadelphia chromosome ,Tyrosine-kinase inhibitor ,myeloid leukemia ,chronic myeloid leukemia ,Leukemia, Myelogenous, Chronic, BCR-ABL Positive ,hemic and lymphatic diseases ,tyrosine kinase inhibitors ,Tumor Cells, Cultured ,medicine ,Humans ,Protein Kinase Inhibitors ,CML ,neoplasms ,Janus Kinases ,apoptosis ,Hematology ,Protein-Tyrosine Kinases ,Hematopoietic Stem Cells ,medicine.disease ,cytokines ,protein-tyrosine kinase ,Thiazoles ,Pyrimidines ,Cytokine ,Imatinib mesylate ,Oncology ,Cancer research ,Cytokines ,Signal transduction ,Tyrosine kinase ,Chronic myelogenous leukemia ,medicine.drug - Abstract
In chronic myeloid leukemia (CML) cell lines, brief exposure to pharmacologically relevant dasatinib concentrations results in apoptosis. In this study, we assess the impact of intensity and duration of Bcr-Abl kinase inhibition on primary CD34+ progenitors of chronic phase CML patients. As CML cells exposed to dasatinib in vivo are in a cytokine-rich environment, we also assessed the effect of cytokines (six growth factors cocktail or granulocyte-macrophage colony-stimulating factor (CSF) or granulocyte-CSF) in combination with dasatinib. In the presence of cytokines, short-term intense Bcr-Abl kinase inhibition (90% p-Crkl inhibition) with 100 nM dasatinib did not reduce CD34+ colony-forming cells (CFCs). In contrast, without cytokines, short-term exposure to dasatinib reduced CML-CD34+ CFCs by 70-80%. When cytokines were added immediately after short-term exposure to dasatinib, CML-CD34+ cells remained viable, suggesting that oncogene dependence of these cells can be overcome by concomitant or subsequent exposure to cytokines. Additional inhibition of Janus tyrosine kinase (Jak) activity re-established the sensitivity of CML progenitors to intense Bcr-Abl kinase inhibition despite the presence of cytokines. These findings support the contention that therapeutic strategies combining intense Bcr-Abl kinase inhibition and blockade of cytokine signaling pathways can be effective for eradication of CML progenitors. Refereed/Peer-reviewed
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- 2010
57. Enhanced expression of transferrin receptor 1 contributes to oncogenic signalling by sphingosine kinase 1
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Stuart M. Pitson, Jason A. Powell, Gregory J. Goodall, Duyen H. Pham, Rosalie Kenyon, Paul A.B. Moretti, Briony L. Gliddon, M Van der Hoek, Anna Tsykin, Pham, DH, Powell, JA, Gliddon, BL, Moretti, PAB, Tsykin, A, Van Der Hoek, M, Kenyon, R, Goodall, GJ, and Pitson, SM
- Subjects
Cancer Research ,Immunoblotting ,Sphingosine kinase ,Fluorescent Antibody Technique ,Transferrin receptor ,Biology ,Real-Time Polymerase Chain Reaction ,Transfection ,Cell Line ,Mice ,Antigens, CD ,Neoplasms ,Receptors, Transferrin ,Genetics ,Animals ,Humans ,Neoplastic transformation ,RNA, Small Interfering ,Receptor ,Molecular Biology ,Oligonucleotide Array Sequence Analysis ,Regulation of gene expression ,Kinase ,DNA microarray ,transferrin receptor ,Cell biology ,Phosphotransferases (Alcohol Group Acceptor) ,neoplastic transformation ,Cell Transformation, Neoplastic ,Gene Expression Regulation ,Biochemistry ,Sphingosine kinase 1 ,expression profiling ,sphingosine kinase ,Gene Knockdown Techniques ,biology.protein ,Signal transduction ,Signal Transduction - Abstract
Sphingosine kinase 1 (SK1) is a lipid kinase that catalyses the formation of sphingosine-1-phosphate (S1P). Considerable evidence has implicated elevated cellular SK1 in tumour development, progression and disease severity. In particular, SK1 has been shown to enhance cell survival and proliferation and induce neoplastic transformation. Although S1P has been found to have both cellsurface G-protein-coupled receptors and intracellular targets, the specific downstream pathways mediating oncogenic signalling by SK1 remain poorly defined. Here, using a gene expression array approach, we have demonstrated a novel mechanism whereby SK1 regulates cell survival, proliferation and neoplastic transformation through enhancing expression of transferrin receptor 1 (TFR1). We showed that elevated levels of SK1 enhanced total as well as cell-surface TFR1 expression, resulting in increased transferrin uptake into cells. Notably, we also found that SK1 activation and localization to the plasma membrane, which are critical for its oncogenic effects, are necessary for regulation of TFR1 expression specifically through engagement of the S1P G-protein coupled receptor, S1P2. Furthermore, we showed that blocking TFR1 function with a neutralizing antibody inhibits SK1-induced cell proliferation, survival and neoplastic transformation of NIH3T3 fibroblasts. Similar effects were observed following antagonism of S1P2. Together these findings suggest that TFR1 has an important role in SK1-mediated oncogenesis. Refereed/Peer-reviewed
- Published
- 2014
58. Dead Pool : Lake Powell, Global Warming, and the Future of Water in the West
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Powell, James Lawrence and Powell, James Lawrence
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- 2023
59. A mountain pine beetle (Coleoptera: Curculionidae) adult development rate model confirms evolved geographic differences.
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Wangen CE, Powell JA, and Bentz BJ
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- Animals, Arizona, Models, Biological, Pinus growth & development, Temperature, Weevils growth & development, Weevils physiology
- Abstract
Insects live in a wide range of thermal environments and have evolved species- and location-specific physiological processes for survival in hot and cold extremes. Thermally driven dormancy strategies, development rates and thresholds are important for synchronizing cohorts within a population and to local climates and often vary among populations within a species. Mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae, Scolytinae), is a widely distributed forest insect native to North America with clinal genetic differentiation in thermally dependent traits. MPB development occurs in Pinus phloem beneath the bark, and its cryptic habitat makes experimentation difficult, particularly for the adult stage. We describe a novel method for modeling MPB adult development following pupation and terminating in emergence from a brood tree. We focus on an Arizona (southern) MPB population with previously described preadult development rates. Field-observed tree attack, adult emergence, and phloem temperature data are combined in a parameterized cohort model and candidate rate curves are evaluated to describe adult emergence timing. Model competition indicates that the Brière rate curve provided the best fit to field data and performed well under cross-validation. Results confirm that the development of Arizona MPB adults is slower than the previously described development rate of more northern Utah adults. Using the estimated adult rate curve in a scenario of increasing mean temperatures, we show that the timing of second-generation adult emergence in the same year would result in cold-intolerant lifestages during winter, limiting the success of bivoltine populations., (Published by Oxford University Press on behalf of Entomological Society of America 2024. This work is written by (a) US Government employee(s) and is in the public domain in the US.)
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- 2024
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60. How modularity and heterotrophy complicate the understanding of the causes of thermal performance curves: the case of feeding rate in a filter-feeding animal.
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Powell JA and Burgess SC
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- Animals, Bryozoa physiology, Feeding Behavior, Phytoplankton physiology, Temperature
- Abstract
Warming global temperatures have consequences for biological rates. Feeding rates reflect the intake of energy that fuels survival, growth and reproduction. However, temperature can also affect food abundance and quality, as well as feeding behavior, which all affect feeding rate, making it challenging to understand the pathways by which temperature affects the intake of energy. Therefore, we experimentally assessed how clearance rate varied across a thermal gradient in a filter-feeding colonial marine invertebrate (the bryozoan Bugula neritina). We also assessed how temperature affects phytoplankton as a food source, and zooid states within a colony that affect energy budgets and feeding behavior. Clearance rate increased linearly from 18°C to 32°C, a temperature range that the population experiences most of the year. However, temperature increased algal cell size, and decreased the proportion of feeding zooids, suggesting indirect effects of temperature on clearance rates. Temperature increased polypide regression, possibly as a stress response because satiation occurred quicker, or because phytoplankton quality declined. Temperature had a greater effect on clearance rate per feeding zooid than it did per total zooids. Together, these results suggest that the effect of temperature on clearance rate at the colony level is not just the outcome of individual zooids feeding more in direct response to temperature but also emerges from temperature increasing polypide regression and the remaining zooids increasing their feeding rates in response. Our study highlights some of the challenges for understanding why temperature affects feeding rates, especially for understudied, yet ecologically important, marine colonial organisms., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)
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- 2024
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61. Venetoclax therapy and emerging resistance mechanisms in acute myeloid leukaemia.
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Nwosu GO, Ross DM, Powell JA, and Pitson SM
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- Humans, Antineoplastic Agents therapeutic use, Antineoplastic Agents pharmacology, Animals, Bridged Bicyclo Compounds, Heterocyclic therapeutic use, Bridged Bicyclo Compounds, Heterocyclic pharmacology, Sulfonamides therapeutic use, Sulfonamides pharmacology, Leukemia, Myeloid, Acute drug therapy, Leukemia, Myeloid, Acute pathology, Leukemia, Myeloid, Acute genetics, Drug Resistance, Neoplasm drug effects
- Abstract
Acute myeloid leukaemia (AML) is a highly aggressive and devastating malignancy of the bone marrow and blood. For decades, intensive chemotherapy has been the frontline treatment for AML but has yielded only poor patient outcomes as exemplified by a 5-year survival rate of < 30%, even in younger adults. As knowledge of the molecular underpinnings of AML has advanced, so too has the development new strategies with potential to improve the treatment of AML patients. To date the most promising of these targeted agents is the BH3-mimetic venetoclax which in combination with standard of care therapies, has manageable non-haematological toxicity and exhibits impressive efficacy. However, approximately 30% of AML patients fail to respond to venetoclax-based regimens and almost all treatment responders eventually relapse. Here, we review the emerging mechanisms of intrinsic and acquired venetoclax resistance in AML and highlight recent efforts to identify novel strategies to overcome resistance to venetoclax., (© 2024. Crown.)
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- 2024
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62. Safety and immunogenicity of a single dose of Tdap compared to Td in pregnant women in Mali and 3 its effect on infant immune responses: a single-centre, randomised, double-blind, active-controlled phase 2 study.
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Haidara FC, Tapia MD, Diallo F, Portillo S, Williams M, Traoré A, Rotrosen E, Hensel E, Makowski M, Selamawi S, Powell JA, Kotloff KL, Pasetti MF, Sow SO, and Neuzil KM
- Abstract
Background: While maternal pertussis vaccination is a strategy to reduce infant morbidity, safety and immunogenicity data are limited in sub-Saharan Africa. We aimed to evaluate the safety of a single dose of tetanus, diphtheria and acellular pertussis vaccine (Tdap) vaccine compared to tetanus and diphtheria vaccine (Td) vaccine in pregnant women in Bamako, Mali and to assess the pertussis toxin (PT) antibody response at birth., Methods: In this phase 2, single-centre, randomised, double-blind, active-controlled study, from 23 January 2019 to 10 July 2019, healthy 18-39 year old women in the second trimester of a singleton pregnancy were randomised 2:1 to receive Tdap or Td. Blood was tested for serum immunoglobulin G (IgG) against PT and other vaccine antigens using a qualified Meso Scale Discovery multiplex immunoassay. The co-primary objectives evaluated safety and birth anti-PT levels. Infant immune responses to whole-cell pertussis vaccine (DTwP) were assessed. Statistical analysis was descriptive. This trial is registered with clinicaltrials.gov, NCT03589768., Findings: 133 women received Tdap and 67 received Td, with 126 and 66 livebirths, respectively. In the Tdap group, 22 serious adverse events (SAEs) including one maternal death occurred in 20 participants (15·0%), with 10 SAEs in 10 participants (14·9%) in the Td group. Among infants, 18 events occurred among 13 participants (10.3%) and 8 SAEs in 6 participants (9.1%), including three and two infant deaths, occurred in Tdap and Td groups, respectively. None were related to study vaccines. Anti-PT geometric mean concentration (GMC) at birth in the Tdap group was higher than in the Td group (55.4 [46.2-66.6] IU/ml vs 7.9 [5.4-11.5] IU/ml). One month after the third dose of DTwP, the GMC in infants born to mothers in the Tdap group were lower compared to the Td group (20.2 [13.7-29.9] IU/ml vs 77.2 [32.2-184.8] IU/ml). By 6 months of age, the anti- PT GMCs were 17.3 [12.8-23.4] IU/ml and 67.1 [35.5-126.7] IU/ml in Tdap and Td groups, respectively. At birth, anti-tetanus toxin (TT) GMCs were higher in infants in the Td vs Tdap group (5.9 [5.0-7.0] IU/ml vs 4.1 [3.5-4.8] IU/ml). Anti-diphtheria toxin GMCs were similar in both groups., Interpretation: Tdap administered to pregnant women in Mali is safe and well-tolerated. Infants of mothers who received Tdap were born with high PT and protective anti-TT antibody levels. By six months of age, after primary vaccination, the PT levels were lower in the Tdap group compared to the Td group. The blunted immune responses to primary DTwP vaccination in the Tdap infant group warrant further study., Funding: This project was funded by National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), under contract numbers 75N93021C00012 (The Emmes Company), and HHSN27220130000221 (University of Maryland, Baltimore). Dr. Susana Portillo was supported by NIH award no. T32AI007524. NIAID, NIH provided Tdap vaccine (BOOSTRIX)., Competing Interests: We declare no competing interests except for KLK, who reports funding to conduct this research from NIAID to her institution., (© 2024 The Authors.)
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- 2024
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63. The 10 th Barossa meeting: Cell Signalling to Cancer Medicine.
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Kan WL, McClure BJ, Hahn CN, and Powell JA
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- Humans, Signal Transduction, Neoplasms genetics, Medicine
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- 2024
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64. An orthotopic syngeneic mouse model of bortezomib-resistant multiple myeloma.
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Li M, Bennett MK, Toubia J, Pope VS, Tea MN, Tamang S, Samuel MS, Anderson PH, Gliddon BL, Powell JA, and Pitson SM
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- Animals, Mice, Bortezomib therapeutic use, Mice, Inbred C57BL, Proteasome Inhibitors therapeutic use, Cell Line, Tumor, Drug Resistance, Neoplasm, Multiple Myeloma drug therapy, Antineoplastic Agents therapeutic use
- Abstract
While bortezomib has significant benefits in multiple myeloma (MM) therapy, the disease remains incurable due to the invariable development of bortezomib resistance. This emphasises the need for advanced models for preclinical evaluation of new therapeutic approaches for bortezomib-resistant MM. Here, we describe the development of an orthotopic syngeneic bortezomib-resistant MM mouse model based on the most well-characterised syngeneic MM mouse model derived from spontaneous MM-forming C57BL/KaLwRij mice. Using bortezomib-resistant 5TGM1 cells, we report and characterise a robust syngeneic mouse model of bortezomib-resistant MM that is well suited to the evaluation of new therapeutic approaches for proteasome inhibitor-resistant MM., (© 2023 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)
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- 2024
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65. Dust storms increase the tolerance of phytoplankton to thermal and pH changes.
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González-Olalla JM, Powell JA, and Brahney J
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- Food Chain, Dust, Hydrogen-Ion Concentration, Ecosystem, Phytoplankton
- Abstract
Aquatic communities are increasingly subjected to multiple stressors through global change, including warming, pH shifts, and elevated nutrient concentrations. These stressors often surpass species tolerance range, leading to unpredictable consequences for aquatic communities and ecosystem functioning. Phytoplankton, as the foundation of the aquatic food web, play a crucial role in controlling water quality and the transfer of nutrients and energy to higher trophic levels. Despite the significance in understanding the effect of multiple stressors, further research is required to explore the combined impact of multiple stressors on phytoplankton. In this study, we used a combination of crossed experiment and mechanistic model to analyze the ecological and biogeochemical effects of global change on aquatic ecosystems and to forecast phytoplankton dynamics. We examined the effect of dust (0-75 mg L
-1 ), temperature (19-27°C), and pH (6.3-7.3) on the growth rate of the algal species Scenedesmus obliquus. Furthermore, we carried out a geospatial analysis to identify regions of the planet where aquatic systems could be most affected by atmospheric dust deposition. Our mechanistic model and our empirical data show that dust exerts a positive effect on phytoplankton growth rate, broadening its thermal and pH tolerance range. Finally, our geospatial analysis identifies several high-risk areas including the highlands of the Tibetan Plateau, western United States, South America, central and southern Africa, central Australia as well as the Mediterranean region where dust-induced changes are expected to have the greatest impacts. Overall, our study shows that increasing dust storms associated with a more arid climate and land degradation can reverse the negative effects of high temperatures and low pH on phytoplankton growth, affecting the biogeochemistry of aquatic ecosystems and their role in the cycles of the elements and tolerance to global change., (© 2023 John Wiley & Sons Ltd.)- Published
- 2024
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66. Genome-wide transcription factor-binding maps reveal cell-specific changes in the regulatory architecture of human HSPCs.
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Subramanian S, Thoms JAI, Huang Y, Cornejo-Páramo P, Koch FC, Jacquelin S, Shen S, Song E, Joshi S, Brownlee C, Woll PS, Chacon-Fajardo D, Beck D, Curtis DJ, Yehson K, Antonenas V, O'Brien T, Trickett A, Powell JA, Lewis ID, Pitson SM, Gandhi MK, Lane SW, Vafaee F, Wong ES, Göttgens B, Alinejad-Rokny H, Wong JWH, and Pimanda JE
- Subjects
- Humans, Gene Expression Regulation, Hematopoiesis genetics, Chromatin metabolism, Core Binding Factor Alpha 2 Subunit genetics, Core Binding Factor Alpha 2 Subunit metabolism, Hematopoietic Stem Cells metabolism
- Abstract
Hematopoietic stem and progenitor cells (HSPCs) rely on a complex interplay among transcription factors (TFs) to regulate differentiation into mature blood cells. A heptad of TFs (FLI1, ERG, GATA2, RUNX1, TAL1, LYL1, LMO2) bind regulatory elements in bulk CD34+ HSPCs. However, whether specific heptad-TF combinations have distinct roles in regulating hematopoietic differentiation remains unknown. We mapped genome-wide chromatin contacts (HiC, H3K27ac, HiChIP), chromatin modifications (H3K4me3, H3K27ac, H3K27me3) and 10 TF binding profiles (heptad, PU.1, CTCF, STAG2) in HSPC subsets (stem/multipotent progenitors plus common myeloid, granulocyte macrophage, and megakaryocyte erythrocyte progenitors) and found TF occupancy and enhancer-promoter interactions varied significantly across cell types and were associated with cell-type-specific gene expression. Distinct regulatory elements were enriched with specific heptad-TF combinations, including stem-cell-specific elements with ERG, and myeloid- and erythroid-specific elements with combinations of FLI1, RUNX1, GATA2, TAL1, LYL1, and LMO2. Furthermore, heptad-occupied regions in HSPCs were subsequently bound by lineage-defining TFs, including PU.1 and GATA1, suggesting that heptad factors may prime regulatory elements for use in mature cell types. We also found that enhancers with cell-type-specific heptad occupancy shared a common grammar with respect to TF binding motifs, suggesting that combinatorial binding of TF complexes was at least partially regulated by features encoded in DNA sequence motifs. Taken together, this study comprehensively characterizes the gene regulatory landscape in rare subpopulations of human HSPCs. The accompanying data sets should serve as a valuable resource for understanding adult hematopoiesis and a framework for analyzing aberrant regulatory networks in leukemic cells., (© 2023 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)
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- 2023
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67. Some children with idiopathic toe walking display sensory processing difficulties but not all: A systematic review.
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Donne JH, Powell JA, Fahey MC, Beare R, Kolic J, and Williams CM
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- Humans, Child, Gait, Walking, Toes, Movement Disorders diagnosis
- Abstract
Aim: Idiopathic toe walking (ITW) is a diagnosis for children who toe walk without another diagnosis known to cause toe walking. Recent research has suggested that children with ITW may have mild motor planning challenges and sensory processing differences. The primary aim of this systematic review was to determine whether children diagnosed with ITW have differences in their sensory processing compared to typically developing children. Secondary aims included determining how sensory processing was assessed in this population and documenting the broad clinometric and psychometric properties of any assessment tools., Methods: MEDLINE, CINAHL, AMED and Embase were searched for relevant literature in English. Studies were eligible for inclusion if they described children aged 3 and 18 with idiopathic toe walking and reported a sensory processing domain., Results: Twelve articles met the inclusion criteria; however, only two papers included data permitting meta-analysis. Meta-analyses of vibration perception threshold using a random effect model were not significant (p = 0.31). Other data were synthesised by narrative and showed a high heterogeneity across multiple sensory processing domains., Conclusion: This study highlights that despite children with ITW often conceptualised as possessing sensory processing challenges, there is little evidence supporting this theory. Further research on sensory processing in children with this gait pattern is necessary., (© 2023 The Authors. Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica.)
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- 2023
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68. Circular RNAs drive oncogenic chromosomal translocations within the MLL recombinome in leukemia.
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Conn VM, Gabryelska M, Toubia J, Kirk K, Gantley L, Powell JA, Cildir G, Marri S, Liu R, Stringer BW, Townley S, Webb ST, Lin H, Samaraweera SE, Bailey S, Moore AS, Maybury M, Liu D, Colella AD, Chataway T, Wallington-Gates CT, Walters L, Sibbons J, Selth LA, Tergaonkar V, D'Andrea RJ, Pitson SM, Goodall GJ, and Conn SJ
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- Animals, Mice, Humans, RNA, Circular genetics, Myeloid-Lymphoid Leukemia Protein genetics, Myeloid-Lymphoid Leukemia Protein metabolism, DNA, Oncogene Proteins, Fusion genetics, Translocation, Genetic, Leukemia genetics, Leukemia pathology
- Abstract
The first step of oncogenesis is the acquisition of a repertoire of genetic mutations to initiate and sustain the malignancy. An important example of this initiation phase in acute leukemias is the formation of a potent oncogene by chromosomal translocations between the mixed lineage leukemia (MLL) gene and one of 100 translocation partners, known as the MLL recombinome. Here, we show that circular RNAs (circRNAs)-a family of covalently closed, alternatively spliced RNA molecules-are enriched within the MLL recombinome and can bind DNA, forming circRNA:DNA hybrids (circR loops) at their cognate loci. These circR loops promote transcriptional pausing, proteasome inhibition, chromatin re-organization, and DNA breakage. Importantly, overexpressing circRNAs in mouse leukemia xenograft models results in co-localization of genomic loci, de novo generation of clinically relevant chromosomal translocations mimicking the MLL recombinome, and hastening of disease onset. Our findings provide fundamental insight into the acquisition of chromosomal translocations by endogenous RNA carcinogens in leukemia., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 Elsevier Inc. All rights reserved.)
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- 2023
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69. Crystals of Aliphatic Derivatives of [Cu(acac) 2 ] have Distinct Atomic-Scale Mechanisms of Bending.
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Thompson AJ, Powell JA, Melville JN, McMurtrie JC, and Clegg JK
- Abstract
Molecular crystals displaying elastic flexibility have important applications in the fields of optoelectronics and nanophotonic technologies. Understanding the mechanisms by which these materials bend is critical to the design of future materials incorporating these properties. Based on the known elastic properties of bis(acetylacetonato)copper(II), a series of 14 aliphatic derivatives are synthesized and crystallized. All those which grew in a needle morphology display noticeable elasticity, with 1D chains of π-stacked molecules parallel to the long metric length of the crystal a consistent crystallographic feature. Crystallographic mapping is used to measure the mechanism of elasticity at an atomic-scale. Symmetric derivatives with ethyl and propyl side chains are found to have different mechanisms of elasticity, which are further distinguished from the previously reported mechanism of bis(acetylacetonato)copper(II). While crystals of bis(acetylacetonato)copper(II) are known to bend elastically via a molecular rotation mechanism, the elasticity of the compounds presented is facilitated by expansion of their π-stacking interactions., (© 2023 The Authors. Small published by Wiley-VCH GmbH.)
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- 2023
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70. Tailoring Implementation Strategies for Cardiovascular Disease Risk Calculator Adoption in Primary Care Clinics.
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Baldwin LM, Tuzzio L, Cole AM, Holden E, Powell JA, and Parchman ML
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- Humans, Primary Health Care, Qualitative Research, Needs Assessment, Cardiovascular Diseases diagnosis, Cardiovascular Diseases prevention & control, Physicians
- Abstract
Introduction: When implementing interventions in primary care, tailoring implementation strategies to practice barriers can be effective, but additional work is needed to understand how to best select these strategies. This study sought to identify clinicians' contributions to the process of tailoring implementation strategies to barriers in clinical settings., Methods: We conducted a modified nominal group exercise involving 8 implementation scientists and 26 primary care clinicians in the WWAMI region Practice and Research Network. Each group identified implementation strategies it felt would best address barriers to using a cardiovascular disease (CVD) risk calculator previously identified across 44 primary care clinics from the Healthy Hearts Northwest pragmatic trial (2015 to 2018). These barriers had been mapped beforehand to the Consolidated Framework for Implementation Research (CFIR) domains. We examined similarities and differences in the strategies that 30% or more of each group identified (agreed-on strategies) for each barrier and for barriers in each CFIR domain. We used the results to demonstrate how strategies might be tailored to individual clinics., Results: Clinicians selected 23 implementation strategies to address 1 or more of the 13 barriers; implementation scientists selected 35. The 2 groups agreed on at least 1 strategy for barriers in each CFIR domain: Inner Setting, Outer Setting, Intervention Characteristics, Characteristics of Individuals, and Process. Conducting local needs assessment and assessing for readiness / identifying barriers and facilitators were the 2 most common implementation strategies chosen only by clinicians., Conclusions: Clinician stakeholders identified implementation strategies that augmented those chosen by implementation scientists, suggesting that codesign of implementation processes between implementation scientists and clinicians may strengthen the process of tailoring strategies to overcome implementation barriers., Competing Interests: Conflicts of interest: None., (© Copyright by the American Board of Family Medicine.)
- Published
- 2022
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71. The first assessment of the genetic diversity and structure of the endangered West Indian manatee in Cuba.
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Alvarez-Aleman A, Hunter ME, Frazer TK, Powell JA, Alfonso EG, and Austin JD
- Subjects
- Animals, Cuba, Microsatellite Repeats, Trichechus genetics, Genetic Variation, Genetics, Population, Trichechus manatus genetics
- Abstract
The coastal waters of Cuba are home to a small, endangered population of West Indian manatee, which would benefit from a comprehensive characterization of the population's genetic variation. We conducted the first genetic assessment of Cuban manatees to determine the extent of the population's genetic structure and characterize the neutral genetic diversity among regions within the archipelago. We genotyped 49 manatees at 18 microsatellite loci, a subset of 27 samples on 1703 single nucleotide polymorphisms (SNPs), and sequenced 59 manatees at the mitochondrial control region. The Cuba manatee population had low nuclear (microsatellites H
E = 0.44, and SNP HE = 0.29) and mitochondrial genetic diversity (h = 0.068 and π = 0.00025), and displayed moderate departures from random mating (microsatellite FIS = 0.12, SNP FIS = 0.10). Our results suggest that the western portion of the archipelago undergoes periodic exchange of alleles based on the evidence of shared ancestry and low but significant differentiation. The southeast Guantanamo Bay region and the western portion of the archipelago were more differentiated than southwest and northwest manatees. The genetic distinctiveness observed in the southeast supports its recognition as a demographically independent unit for natural resource management regardless of whether it is due to historical isolation or isolation by distance. Estimates of the regional effective population sizes, with the microsatellite and SNP datasets, were small (all Ne < 60). Subsequent analyses using additional samples could better examine how the observed structure is masking simple isolation by distance patterns or whether ecological or biogeographic forces shape genetic patterns., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)- Published
- 2022
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72. Targeting the integrated stress response in hematologic malignancies.
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Nwosu GO, Powell JA, and Pitson SM
- Abstract
While numerous targeted therapies have been recently adopted to improve the treatment of hematologic malignancies, acquired or intrinsic resistance poses a significant obstacle to their efficacy. Thus, there is increasing need to identify novel, targetable pathways to further improve therapy for these diseases. The integrated stress response is a signaling pathway activated in cancer cells in response to both dysregulated growth and metabolism, and also following exposure to many therapies that appears one such targetable pathway for improved treatment of these diseases. In this review, we discuss the role of the integrated stress response in the biology of hematologic malignancies, its critical involvement in the mechanism of action of targeted therapies, and as a target for pharmacologic modulation as a novel strategy for the treatment of hematologic malignancies., (© 2022. The Author(s).)
- Published
- 2022
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73. Oviposition Model for a Southern Population of Mountain Pine Beetle.
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Wangen CE, Powell JA, and Bentz BJ
- Subjects
- Animals, Female, Mathematical Concepts, Models, Biological, Oviposition, Coleoptera, Pinus
- Abstract
We develop a predictive oviposition model for a southern population of mountain pine beetle (MPB) using a previously developed rate curve, incorporating variation in both oviposition rate and fecundity. We also introduce a method for determining the time delay before oviposition. The model describes the probability of oviposition for a season of MPB attacks using hourly phloem temperature and adult MPB attack data. We also develop an asymptotic approximation of MPB oviposition that is much less computationally taxing. The detailed oviposition model and its asymptotic approximation are compared with other ovipositional models for MPB; the predictive capacity of each model is evaluated using previously published observations., (© 2022. The Author(s), under exclusive licence to Society for Mathematical Biology.)
- Published
- 2022
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74. Albertanus of Brescia : The Pursuit of Happiness in the Early Thirteenth Century
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Powell, James M. and Powell, James M.
- Published
- 2016
75. Ceramide-induced integrated stress response overcomes Bcl-2 inhibitor resistance in acute myeloid leukemia.
- Author
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Lewis AC, Pope VS, Tea MN, Li M, Nwosu GO, Nguyen TM, Wallington-Beddoe CT, Moretti PAB, Anderson D, Creek DJ, Costabile M, Ali SR, Thompson-Peach CAL, Dredge BK, Bert AG, Goodall GJ, Ekert PG, Brown AL, D'Andrea R, Robinson N, Pitman MR, Thomas D, Ross DM, Gliddon BL, Powell JA, and Pitson SM
- Subjects
- Apoptosis, Bridged Bicyclo Compounds, Heterocyclic therapeutic use, Cell Line, Tumor, Ceramides pharmacology, Humans, Myeloid Cell Leukemia Sequence 1 Protein metabolism, Proto-Oncogene Proteins c-bcl-2 metabolism, Antineoplastic Agents therapeutic use, Leukemia, Myeloid, Acute drug therapy, Leukemia, Myeloid, Acute genetics, Leukemia, Myeloid, Acute metabolism
- Abstract
Inducing cell death by the sphingolipid ceramide is a potential anticancer strategy, but the underlying mechanisms remain poorly defined. In this study, triggering an accumulation of ceramide in acute myeloid leukemia (AML) cells by inhibition of sphingosine kinase induced an apoptotic integrated stress response (ISR) through protein kinase R-mediated activation of the master transcription factor ATF4. This effect led to transcription of the BH3-only protein Noxa and degradation of the prosurvival Mcl-1 protein on which AML cells are highly dependent for survival. Targeting this novel ISR pathway, in combination with the Bcl-2 inhibitor venetoclax, synergistically killed primary AML blasts, including those with venetoclax-resistant mutations, as well as immunophenotypic leukemic stem cells, and reduced leukemic engraftment in patient-derived AML xenografts. Collectively, these findings provide mechanistic insight into the anticancer effects of ceramide and preclinical evidence for new approaches to augment Bcl-2 inhibition in the therapy of AML and other cancers with high Mcl-1 dependency., (© 2022 by The American Society of Hematology.)
- Published
- 2022
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76. Characterization of an aerosolized nanoparticle beam beyond the diffraction limit through strong field ionization.
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Davino M, Saule T, Helming NG, Powell JA, and Trallero-Herrero C
- Abstract
The study of nanomaterials is an active area of research for technological applications as well as fundamental science. A common method for studying properties of isolated nanoparticles is by an in-vacuum particle beam produced via an aerodynamic lens. Despite being common practice, characterization of such beams has proven difficult as light scattering detection techniques fail for particles with sizes beyond the diffraction limit. Here we present a new technique for characterizing such nanoparticle beams using strong field ionization. By focusing an ultrafast, mJ-level laser into the particle beam, a nanoparticle within the laser focus is ionized and easily detected by its ejected electrons. This method grants direct access to the nanoparticle density at the location of the focus, and by scanning the focus through the transverse and longitudinal profiles of the particle beam we attain the 3-dimensional particle density distribution for a cylindrically symmetric beam. Further, we show that strong field ionization is effective in detecting spherical nanoparticles as small as 10 nm in diameter. Additionally, this technique is an effective tool in optimizing the particle beam for specific applications. As an example we show that the particle beam density and width can be manipulated by restricting the gas flow into the aerodynamic lens., (© 2022. The Author(s).)
- Published
- 2022
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77. The Universe as It Really Is : Earth, Space, Matter, and Time
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SCOTT, THOMAS R., POWELL, JAMES LAWRENCE, with the assistance of, SCOTT, THOMAS R., and POWELL, JAMES LAWRENCE
- Published
- 2018
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78. Four Revolutions in the Earth Sciences : From Heresy to Truth
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Powell, James Lawrence and Powell, James Lawrence
- Published
- 2014
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79. Muslims Under Latin Rule, 1100-1300
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Powell, James M., Editor and Powell, James M.
- Published
- 2014
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80. A Phase Ib Dose Escalation Trial of RO4929097 (a γ-secretase inhibitor) in Combination with Exemestane in Patients with ER + Metastatic Breast Cancer (MBC).
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Means-Powell JA, Mayer IA, Ismail-Khan R, Del Valle L, Tonetti D, Abramson VG, Sanders MS, Lush RM, Sorrentino C, Majumder S, and Miele L
- Subjects
- Aged, Breast Neoplasms pathology, Dose-Response Relationship, Drug, Drug Administration Schedule, Female, Humans, Maximum Tolerated Dose, Middle Aged, Neoplasm Metastasis, Receptor, Notch3, Receptors, Notch therapeutic use, Androstadienes therapeutic use, Antineoplastic Agents therapeutic use, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Benzazepines therapeutic use, Breast Neoplasms drug therapy, Fluorocarbons therapeutic use
- Abstract
PRECLINICAL STUDIES: have demonstrated a complex cross-talk between Notch and estrogen signaling in ERα-positive breast cancer. Gamma-secretase inhibitors (GSIs) are investigational agents that block the cleavage and activation of Notch receptors. In animal models of endocrine-resistant breast cancer, combinations of tamoxifen and GSIs produce additive or synergistic efficacy, while decreasing the intestinal toxicity of GSIs. However, results of a clinical trial of a GSI-endocrine therapy combination in the metastatic setting have not been published to date, nor had the safety of such combinations been investigated with longer term treatment. We conducted a phase 1b dose escalation trial (NCT01149356) of GSI RO4929097 with exemestane in patients with ERα+, metastatic breast cancer (MBC) STUDY OBJECTIVES: To determine the safety, tolerability and maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D) of RO4929097 when administered in combination with exemestane in patients with estrogen receptor positive metastatic breast cancer RESULTS: We enrolled 15 patients with MBC. Of 14 evaluable patients, one had a partial response, 6 had stable disease and 7 progressive disease. Twenty % of patients had stable disease for ≥ 6 months. Common toxicities included nausea (73.3%), anorexia (60%), hyperglycemia (53.3%), hypophosphatemia (46.7%), fatigue (66.7%) and cough (33.0%). Grade 3 toxicities were uncommon, and included hypophosphatemia (13%) and rash (6.3%). Rash was the only DLT observed at 140 mg/d. Results suggest a possible recommended phase 2 dose of 90 mg/d. Ten patients with evaluable archival tissue showed expression of PKCα, which correlated with expression of Notch4. Mammospheres from a PKCα-expressing, endocrine-resistant T47D cell line were inhibited by a GSI-fulvestrant combination CONCLUSIONS: Our data indicate that combinations including endocrine therapy and Notch inhibitors deserve further investigation in endocrine-resistant ERα-positive breast cancer., (Copyright © 2021. Published by Elsevier Inc.)
- Published
- 2022
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81. Evaluating the Efficacy of Eradicating Gardnerella vaginalis Vaginal Colonization With Amoxicillin: A Randomized, Double-Blind, Phase 2 Study.
- Author
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McNeil CJ, Tan A, Powell JA, Pontius A, Lewis A, Myler N, and Schwebke JR
- Subjects
- Adolescent, Adult, Amoxicillin therapeutic use, Female, Humans, Middle Aged, Vagina microbiology, Young Adult, Gardnerella vaginalis, Vaginosis, Bacterial diagnosis
- Abstract
Background: Research suggests that Gardnerella vaginalis (GV) is the keystone pathogen in bacterial vaginosis (BV). Knowledge gaps exist regarding the role of GV eradication in the development of BV. This study was designed to test the hypothesis that vaginal colonization with GV could be eradicated by treatment of women without BV with amoxicillin, a drug highly active against GV. If GV is necessary for the development of BV, then eradication of GV may prevent the development of BV., Methods: We conducted a randomized control trial of amoxicillin 500 mg twice daily versus placebo for 7 days in women aged 18 to 45 years without vaginitis who screened positive for vaginal colonization with GV by quantitative polymerase chain reaction. Test-of-cure visit for GV was conducted at day 21., Results: One hundred seventy-two women met preliminary criteria and were screened for enrollment. Ninety-seven GV-positive women were randomized to receive amoxicillin versus placebo. Eradication of GV occurred in 21% of women randomized to amoxicillin versus 16% on placebo (P = 0.757). In the 4 weeks between screening and test-of-cure visit, 16 of 92 (17%) of participants developed Nugent scores greater than 3 with 8 of 92 (9%) having BV. All of these were in participants in whom GV was not eradicated (P = 0.035)., Conclusions: The study failed to show a benefit of treatment with amoxicillin to eradicate GV. No participants in whom GV was eradicated had progression to abnormal vaginal flora during the study period., Competing Interests: Conflict of Interest: None declared., (Copyright © 2021 American Sexually Transmitted Diseases Association. All rights reserved.)
- Published
- 2022
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82. The sphingosine 1-phosphate receptor 2/4 antagonist JTE-013 elicits off-target effects on sphingolipid metabolism.
- Author
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Pitman MR, Lewis AC, Davies LT, Moretti PAB, Anderson D, Creek DJ, Powell JA, and Pitson SM
- Subjects
- HEK293 Cells, Humans, Kinetics, Oxidoreductases chemistry, Oxidoreductases genetics, Oxidoreductases metabolism, Pyrazoles pharmacology, Pyridines pharmacology, Sphingosine-1-Phosphate Receptors genetics, Pyrazoles chemistry, Pyridines chemistry, Sphingolipids metabolism, Sphingosine-1-Phosphate Receptors antagonists & inhibitors, Sphingosine-1-Phosphate Receptors metabolism
- Abstract
Sphingosine 1-phosphate (S1P) is a signaling lipid that has broad roles, working either intracellularly through various protein targets, or extracellularly via a family of five G-protein coupled receptors
. Agents that selectively and specifically target each of the S1P receptors have been sought as both biological tools and potential therapeutics. JTE-013, a small molecule antagonist of S1P receptors 2 and 4 (S1P2 and S1P4 ) has been widely used in defining the roles of these receptors in various biological processes. Indeed, our previous studies showed that JTE-013 had anti-acute myeloid leukaemia (AML) activity, supporting a role for S1P2 in the biology and therapeutic targeting of AML. Here we examined this further and describe lipidomic analysis of AML cells that revealed JTE-013 caused alterations in sphingolipid metabolism, increasing cellular ceramides, dihydroceramides, sphingosine and dihydrosphingosine. Further examination of the mechanisms behind these observations showed that JTE-013, at concentrations frequently used in the literature to target S1P2/4 , inhibits several sphingolipid metabolic enzymes, including dihydroceramide desaturase 1 and both sphingosine kinases. Collectively, these findings demonstrate that JTE-013 can have broad off-target effects on sphingolipid metabolism and highlight that caution must be employed in interpreting the use of this reagent in defining the roles of S1P2/4 ., (© 2022. The Author(s).)- Published
- 2022
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83. Warming increased bark beetle-induced tree mortality by 30% during an extreme drought in California.
- Author
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Robbins ZJ, Xu C, Aukema BH, Buotte PC, Chitra-Tarak R, Fettig CJ, Goulden ML, Goodsman DW, Hall AD, Koven CD, Kueppers LM, Madakumbura GD, Mortenson LA, Powell JA, and Scheller RM
- Subjects
- Animals, Droughts, Pinus ponderosa, Plant Bark, Trees, Coleoptera, Pinus
- Abstract
Quantifying the responses of forest disturbances to climate warming is critical to our understanding of carbon cycles and energy balances of the Earth system. The impact of warming on bark beetle outbreaks is complex as multiple drivers of these events may respond differently to warming. Using a novel model of bark beetle biology and host tree interactions, we assessed how contemporary warming affected western pine beetle (Dendroctonus brevicomis) populations and mortality of its host, ponderosa pine (Pinus ponderosa), during an extreme drought in the Sierra Nevada, California, United States. When compared with the field data, our model captured the western pine beetle flight timing and rates of ponderosa pine mortality observed during the drought. In assessing the influence of temperature on western pine beetles, we found that contemporary warming increased the development rate of the western pine beetle and decreased the overwinter mortality rate of western pine beetle larvae leading to increased population growth during periods of lowered tree defense. We attribute a 29.9% (95% CI: 29.4%-30.2%) increase in ponderosa pine mortality during drought directly to increases in western pine beetle voltinism (i.e., associated with increased development rates of western pine beetle) and, to a much lesser extent, reductions in overwintering mortality. These findings, along with other studies, suggest each degree (°C) increase in temperature may have increased the number of ponderosa pine killed by upwards of 35%-40% °C
-1 if the effects of compromised tree defenses (15%-20%) and increased western pine beetle populations (20%) are additive. Due to the warming ability to considerably increase mortality through the mechanism of bark beetle populations, models need to consider climate's influence on both host tree stress and the bark beetle population dynamics when determining future levels of tree mortality., (© 2021 John Wiley & Sons Ltd.)- Published
- 2022
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- View/download PDF
84. Resensitising proteasome inhibitor-resistant myeloma with sphingosine kinase 2 inhibition.
- Author
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Bennett MK, Li M, Tea MN, Pitman MR, Toubia J, Wang PP, Anderson D, Creek DJ, Orlowski RZ, Gliddon BL, Powell JA, Wallington-Beddoe CT, and Pitson SM
- Subjects
- Animals, Antineoplastic Agents chemistry, Antineoplastic Agents therapeutic use, Bortezomib chemistry, Bortezomib pharmacology, Cell Line, Tumor, Cell Survival drug effects, Disease Models, Animal, Dose-Response Relationship, Drug, Enzyme Inhibitors therapeutic use, Gene Knockout Techniques, Humans, Mice, Multiple Myeloma drug therapy, Multiple Myeloma genetics, Multiple Myeloma metabolism, Multiple Myeloma pathology, Proteasome Inhibitors chemistry, Proteasome Inhibitors therapeutic use, Structure-Activity Relationship, Unfolded Protein Response drug effects, Xenograft Model Antitumor Assays, Antineoplastic Agents pharmacology, Drug Resistance, Neoplasm drug effects, Enzyme Inhibitors pharmacology, Phosphotransferases (Alcohol Group Acceptor) antagonists & inhibitors, Proteasome Inhibitors pharmacology
- Abstract
The introduction of the proteasome inhibitor bortezomib into treatment regimens for myeloma has led to substantial improvement in patient survival. However, whilst bortezomib elicits initial responses in many myeloma patients, this haematological malignancy remains incurable due to the development of acquired bortezomib resistance. With other patients presenting with disease that is intrinsically bortezomib resistant, it is clear that new therapeutic approaches are desperately required to target bortezomib-resistant myeloma. We have previously shown that targeting sphingolipid metabolism with the sphingosine kinase 2 (SK2) inhibitor K145 in combination with bortezomib induces synergistic death of bortezomib-naïve myeloma. In the current study, we have demonstrated that targeting sphingolipid metabolism with K145 synergises with bortezomib and effectively resensitises bortezomib-resistant myeloma to this proteasome inhibitor. Notably, these effects were dependent on enhanced activation of the unfolded protein response, and were observed in numerous separate myeloma models that appear to have different mechanisms of bortezomib resistance, including a new bortezomib-resistant myeloma model we describe which possesses a clinically relevant proteasome mutation. Furthermore, K145 also displayed synergy with the next-generation proteasome inhibitor carfilzomib in bortezomib-resistant and carfilzomib-resistant myeloma cells. Together, these findings indicate that targeting sphingolipid metabolism via SK2 inhibition may be effective in combination with a broad spectrum of proteasome inhibitors in the proteasome inhibitor resistant setting, and is an approach worth clinical exploration., Competing Interests: Declaration of competing interests The authors declare that they have no competing interests., (Copyright © 2021. Published by Elsevier Inc.)
- Published
- 2022
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85. Crusade and Christendom : Annotated Documents in Translation from Innocent III to the Fall of Acre, 1187-1291
- Author
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Bird, Jessalynn, Peters, Edward, Powell, James M., Bird, Jessalynn, Peters, Edward, and Powell, James M.
- Published
- 2013
86. Doxycycline Versus Azithromycin for the Treatment of Rectal Chlamydia in Men Who Have Sex With Men: A Randomized Controlled Trial.
- Author
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Dombrowski JC, Wierzbicki MR, Newman LM, Powell JA, Miller A, Dithmer D, Soge OO, and Mayer KH
- Subjects
- Anti-Bacterial Agents therapeutic use, Azithromycin therapeutic use, Chlamydia trachomatis, Double-Blind Method, Doxycycline therapeutic use, Homosexuality, Male, Humans, Male, Chlamydia Infections drug therapy, Sexual and Gender Minorities
- Abstract
Background: Azithromycin and doxycycline are both recommended treatments for rectal Chlamydia trachomatis (CT) infection, but observational studies suggest that doxycycline may be more effective., Methods: This randomized, double-blind, placebo-controlled trial compared azithromycin (single 1-g dose) versus doxycycline (100 mg twice daily for 7 days) for the treatment of rectal CT in men who have sex with men (MSM) in Seattle and Boston. Participants were enrolled after a diagnosis of rectal CT in clinical care and underwent repeated collection of rectal swabs for nucleic acid amplification testing (NAAT) at study enrollment and 2 weeks and 4 weeks postenrollment. The primary outcome was microbiologic cure (CT-negative NAAT) at 4 weeks. The complete case (CC) population included participants with a CT-positive NAAT at enrollment and a follow-up NAAT result; the intention-to-treat (ITT) population included all randomized participants., Results: Among 177 participants enrolled, 135 (76%) met CC population criteria for the 4-week follow-up visit. Thirty-three participants (19%) were excluded because the CT NAAT repeated at enrollment was negative. Microbiologic cure was higher with doxycycline than azithromycin in both the CC population (100% [70 of 70] vs 74% [48 of 65]; absolute difference, 26%; 95% confidence interval [CI], 16-36%; P < .001) and the ITT population (91% [80 of 88] vs 71% [63 of 89]; absolute difference, 20%; 95% CI, 9-31%; P < .001)., Conclusions: A 1-week course of doxycycline was significantly more effective than a single dose of azithromycin for the treatment of rectal CT in MSM., Clinical Trials Registration: NCT03608774., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
- Published
- 2021
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87. Between God and Man
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Pope Innocent III, Vause, Corinne J., Gardiner, Frank C., Powell, James M., Foreword by, Pope Innocent III, Vause, Corinne J., Gardiner, Frank C., and Powell, James M.
- Published
- 2012
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88. The Inquisition of Climate Science
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Powell, James Lawrence and Powell, James Lawrence
- Published
- 2011
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89. The Deeds of Pope Innocent III
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Anonymous, Powell, James M., Translated with an Introduction and Notes by, Anonymous, and Powell, James M.
- Published
- 2011
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90. Anatomy of a Crusade, 1213-1221
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POWELL, JAMES M. and POWELL, JAMES M.
- Published
- 2011
91. Homochiral Dodecanuclear Lanthanide "Cage in Cage" for Enantioselective Separation.
- Author
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Zhu C, Tang H, Yang K, Fang Y, Wang KY, Xiao Z, Wu X, Li Y, Powell JA, and Zhou HC
- Abstract
It is extremely difficult to anticipate the structure and the stereochemistry of a complex, particularly when the ligand is flexible and the metal node adopts diverse coordination numbers. When trivalent lanthanides (Ln
III ) and enantiopure amino acid ligands are utilized as building blocks, self-assembly sometimes yields rare chiral polynuclear structures. In this study, an enantiopure carboxyl-functionalized amino acid-based ligand with C3 symmetry reacts with lanthanum cations to give a homochiral porous coordination cage, (Δ/Λ)12 - PCC-57 . The dodecanuclear lanthanide cage has an unprecedented octahedral "cage-in-cage" framework. During the self-assembly, the chirality is transferred from the enantiopure ligand and fixed by the binuclear lanthanide cluster to give 12 metal centers that have either Δ or Λ homochiral stereochemistry. The cage exhibits excellent enantioselective separation of racemic alcohols, 2,3-dihydroquinazolinones, and multiple commercially available drugs. This finding exhibits a rare example of a multinuclear lanthanide complex with a dual-walled topology and homochirality. The highly ordered self-assembly and self-sorting of flexible amino acids and lanthanides shed light on the chiral transformation between different complicated artificial systems that mimic natural enzymes.- Published
- 2021
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- View/download PDF
92. Resistance-Guided Treatment of Gonorrhea: A Prospective Clinical Study.
- Author
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Klausner JD, Bristow CC, Soge OO, Shahkolahi A, Waymer T, Bolan RK, Philip SS, Asbel LE, Taylor SN, Mena LA, Goldstein DA, Powell JA, Wierzbicki MR, and Morris SR
- Subjects
- Anti-Bacterial Agents pharmacology, Anti-Bacterial Agents therapeutic use, Ciprofloxacin therapeutic use, Drug Resistance, Bacterial, Humans, Microbial Sensitivity Tests, Neisseria gonorrhoeae genetics, Prospective Studies, Gonorrhea drug therapy
- Abstract
Background: Novel treatment strategies to slow the continued emergence and spread of antimicrobial resistance in Neisseria gonorrhoeae are urgently needed. A molecular assay that predicts in vitro ciprofloxacin susceptibility is now available but has not been systematically studied in human infections., Methods: Using a genotypic polymerase chain reaction assay to determine the status of the N. gonorrhoeae gyrase subunit A serine 91 codon, we conducted a multisite prospective clinical study of the efficacy of a single oral dose of ciprofloxacin 500 mg in patients with culture-positive gonorrhea. Follow-up specimens for culture were collected to determine microbiological cure 5-10 days post-treatment., Results: Of the 106 subjects possessing culture-positive infections with wild-type gyrA serine N. gonorrhoeae genotype, the efficacy of single-dose oral ciprofloxacin treatment in the per-protocol population was 100% (95% 1-sided confidence interval, 97.5-100%)., Conclusions: Resistance-guided treatment of N. gonorrhoeae infections with single-dose oral ciprofloxacin was highly efficacious. The widespread introduction and scale-up of gyrA serine 91 genotyping in N. gonorrhoeae infections could have substantial medical and public health benefits in settings where the majority of gonococcal infections are ciprofloxacin susceptible., Clinical Trials Registration: NCT02961751., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
- Published
- 2021
- Full Text
- View/download PDF
93. Author Correction: Targeting sphingolipid metabolism as an approach for combination therapies in haematological malignancies.
- Author
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Lewis AC, Wallington-Beddoe CT, Powell JA, and Pitson SM
- Published
- 2021
- Full Text
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94. Modulating the stacking modes of nanosized metal-organic frameworks by morphology engineering for isomer separation.
- Author
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Xu M, Meng SS, Cai P, Tang WQ, Yin YD, Powell JA, Zhou HC, and Gu ZY
- Abstract
Modulating different stacking modes of nanoscale metal-organic frameworks (MOFs) introduces different properties and functionalities but remains a great challenge. Here, we describe a morphology engineering method to modulate the stacking modes of nanoscale NU-901. The nanoscale NU-901 is stacked through solvent removal after one-pot solvothermal synthesis, in which different morphologies from nanosheets (NS) to interpenetrated nanosheets (I-NS) and nanoparticles (NP) were obtained successfully. The stacked NU-901-NS, NU-901-I-NS, and NU-901-NP exhibited relatively aligned stacking, random stacking, and close packing, respectively. The three stacked nanoscale NU-901 exhibited different separation abilities and all showed better performance than bulk phase NU-901. Our work provides a new morphology engineering route for the modulation of the stacking modes of nano-sized MOFs and improves the separation abilities of MOFs., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)
- Published
- 2021
- Full Text
- View/download PDF
95. Barriers to Implementing Cardiovascular Risk Calculation in Primary Care: Alignment With the Consolidated Framework for Implementation Research.
- Author
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Tuzzio L, O'Meara ES, Holden E, Parchman ML, Ralston JD, Powell JA, and Baldwin LM
- Subjects
- Delivery of Health Care, Heart Disease Risk Factors, Humans, Primary Health Care, Risk Factors, Cardiovascular Diseases prevention & control
- Abstract
Introduction: Cardiovascular disease risk calculators can inform and guide preventive strategies and treatment decisions by clinicians and patients. However, their uptake in primary care has been slow despite the recommendation in national cardiovascular disease prevention guidelines. Identifying the barriers to the implementation of cardiovascular disease risk calculators is essential for promoting their adoption., Methods: The authors qualitatively analyzed structured physician educator notes written during an outreach education intervention with 44 small- and medium-sized primary care clinics that participated in the Agency for Healthcare Research and Quality‒funded EvidenceNOW Healthy Hearts Northwest trial. The authors coded barriers to the implementation of cardiovascular disease risk calculation and aligned them to the Consolidated Framework for Implementation Research., Results: The authors identified 13 barriers from the physician educators' notes. The majority (n=8, 62%) mapped to the framework's Inner Setting domain. The 5 most commonly noted barriers were (1) time constraints to use a calculator (N=23 clinics), (2) limitations to accessing a calculator or the necessary information to use a calculator (N=22 clinics), (3) no or minimal buy-in from clinicians or staff to use a calculator (N=19 clinics), (4) reported patient fear of side effects from statin medications or patient dislike of taking medications per the guidelines (N=17 clinics), and (5) lack of documented clinic workflow for using a calculator (N=16 clinics)., Conclusions: To improve the uptake of cardiovascular disease risk calculation in primary care, future cardiovascular disease prevention and implementation research should consider tailoring interventions to the common barriers to implementing cardiovascular disease risk calculation., Trial Registration: This study is registered at www.clinicaltrials.gov NCT02839382., (Copyright © 2020 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.)
- Published
- 2021
- Full Text
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96. Health Equity and the Circle of Human Concern.
- Author
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Powell JA and Toppin E
- Subjects
- COVID-19 ethnology, Humans, Health Equity ethics, Health Status Disparities, Healthcare Disparities ethnology, Public Health ethics, Racism
- Abstract
Using the inequality exposed by the COVID-19 pandemic as a vivid example, this article focuses on health equity from the standpoint of structural marginalization-here, described as being marked as an "other" outside of the circle of human concern. This process leads to tension between the principles of liberty and equality and contributes to the creation of systemic disadvantage as manifested in health disparities. Creating an equitable health system must begin with this root understanding and generate greater belonging through the policy process of targeted universalism. Targeted universalism replaces a disparities framework with one in which a universal goal is identified but targeted strategies to meet each population group's needs are employed., (© 2021 American Medical Association. All Rights Reserved.)
- Published
- 2021
- Full Text
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97. Clinical MDR1 inhibitors enhance Smac-mimetic bioavailability to kill murine LSCs and improve survival in AML models.
- Author
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Morrish E, Copeland A, Moujalled DM, Powell JA, Silke N, Lin A, Jarman KE, Sandow JJ, Ebert G, Mackiewicz L, Beach JA, Christie EL, Lewis AC, Pomilio G, Fischer KC, MacPherson L, Bowtell DDL, Webb AI, Pellegrini M, Dawson MA, Pitson SM, Wei AH, Silke J, and Brumatti G
- Subjects
- Animals, Biological Availability, Dipeptides, Humans, Indoles, Inhibitor of Apoptosis Proteins metabolism, Mice, Leukemia, Myeloid, Acute drug therapy
- Abstract
The specific targeting of inhibitor of apoptosis (IAP) proteins by Smac-mimetic (SM) drugs, such as birinapant, has been tested in clinical trials of acute myeloid leukemia (AML) and certain solid cancers. Despite their promising safety profile, SMs have had variable and limited success. Using a library of more than 5700 bioactive compounds, we screened for approaches that could sensitize AML cells to birinapant and identified multidrug resistance protein 1 inhibitors (MDR1i) as a class of clinically approved drugs that can enhance the efficacy of SM therapy. Genetic or pharmacological inhibition of MDR1 increased intracellular levels of birinapant and sensitized AML cells from leukemia murine models, human leukemia cell lines, and primary AML samples to killing by birinapant. The combination of clinical MDR1 and IAP inhibitors was well tolerated in vivo and more effective against leukemic cells, compared with normal hematopoietic progenitors. Importantly, birinapant combined with third-generation MDR1i effectively killed murine leukemic stem cells (LSCs) and prolonged survival of AML-burdened mice, suggesting a therapeutic opportunity for AML. This study identified a drug combination strategy that, by efficiently killing LSCs, may have the potential to improve outcomes in patients with AML., (© 2020 by The American Society of Hematology.)
- Published
- 2020
- Full Text
- View/download PDF
98. A Single Bout of Foam Rolling Increases Flexibility of the Hip Adductor Muscles without Compromising Strength.
- Author
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Connolly G, Hammer RL, Powell JA, and O'Connor PL
- Abstract
Foam rolling (FR) is a method of self-myofascial release (SMR) implemented to reduce tension in underlying soft tissue, leading to increased range of motion (ROM). The hip adductor muscles of the groin are commonly less flexible and often a site for soft tissue injuries. Limited research has been done to determine the most effective flexibility exercises to increase ROM in the groin muscles prior to exercise without comprising strength. The purpose was to determine the effect of an acute bout of FR on passive groin flexibility and strength. Randomized crossover study with 3 × 2 (Condition × Time) repeated measures ANOVA statistical design. 40 volunteers ( n = 20 males; n = 20 females) with limited flexibility in groin ROM participated. Following warm-up, maximal voluntary isometric contraction (MVC) and static ROM were measured pre and postintervention. Conditions included 60 seconds of FR, SS, and CON. The Condition × Time interaction was not significant for MVC or ROM. A main effect of time showed a significant increase in ROM from pre to post for FR (1.2°, p < 0.001), SS (1.0°, p < 0.001), and CON (0.5°, p = 0.039). No significant changes in MVC were observed for FR from pre to post ( p > 0.05), whereas SS and CON both increased ( p < 0.05). An increase in passive groin ROM after acute bouts of SMR or SS without compromising MVC was observed. This suggests that 60 seconds of FR may be employed before exercise to improve flexibility without strength decrement.
- Published
- 2020
99. Correlating Abdominal Wall Thickness and Body Mass Index to Predict Usefulness of Right Lower Quadrant Ultrasound for Evaluation of Pediatric Appendicitis.
- Author
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Kwon JK, Trexler N, Reisch J, Pfeifer CM, Ginos J, Powell JA, Veltkamp J, Anene A, Fernandes N, and Chen LE
- Subjects
- Adolescent, Body Mass Index, Child, Child, Preschool, Female, Humans, Male, Tomography, X-Ray Computed, Ultrasonography, Abdominal Wall physiology, Appendicitis diagnostic imaging, Appendix diagnostic imaging
- Abstract
Objectives: To inform selective and efficient use of appendix ultrasound (US) beyond adult parameters of body mass index (BMI) of less than 25 kg/m, we correlate abdominal wall thickness (AWT) with age and BMI to generate parameters for male and female children. Information presented in chart format can aid in the decision to utilize US for the evaluation of appendicitis., Methods: In this observational study, 1600 pediatric computed tomography scans of the abdomen and pelvis were analyzed to obtain measurements of AWT in the right lower quadrant. Measurements were correlated by patient age, BMI, and sex. Results and consensus-based recommendations were presented in chart format with color-coded groupings to allow for convenient referencing in the clinical setting., Results: One thousand four hundred eighty-eight computed tomography scans and AWT measurements were included. All age groups with BMI of less than 25 kg/m and all male and female groups younger than 6 years regardless of BMI had median AWT of less than 4 cm resulting in strong recommendation for US. Males older than 6 years and all female age groups with BMI of greater than 30 kg/m and female older than 15 years and BMI of greater than 25 kg/m had AWT of more than 5 cm resulting in low recommendation for US., Conclusions: While the BMI cutoff standard of less than 25 kg/m for usefulness of appendix US holds in the adult population, our data expand the acceptable range in children younger than 9 years regardless of BMI and male children with BMI up to 30 kg/m. Female children younger than 15 years with a BMI up to 30 kg/m may also be amenable to right lower quadrant US based on AWT. These parameters inform selective and efficient use of US for appendix evaluation.
- Published
- 2020
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100. Kelch-like protein 5-mediated ubiquitination of lysine 183 promotes proteasomal degradation of sphingosine kinase 1.
- Author
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Powell JA, Pitman MR, Zebol JR, Moretti PAB, Neubauer HA, Davies LT, Lewis AC, Dagley LF, Webb AI, Costabile M, and Pitson SM
- Subjects
- Amino Acid Motifs, Carrier Proteins genetics, Cullin Proteins genetics, Cullin Proteins metabolism, Humans, Lysine genetics, Microfilament Proteins genetics, Phosphotransferases (Alcohol Group Acceptor) genetics, Proteasome Endopeptidase Complex genetics, Proteolysis, Ubiquitination, Carrier Proteins metabolism, Lysine metabolism, Microfilament Proteins metabolism, Phosphotransferases (Alcohol Group Acceptor) chemistry, Phosphotransferases (Alcohol Group Acceptor) metabolism, Proteasome Endopeptidase Complex metabolism
- Abstract
Sphingosine kinase 1 (SK1) is a signalling enzyme that catalyses the phosphorylation of sphingosine to generate the bioactive lipid sphingosine 1-phosphate (S1P). A number of SK1 inhibitors and chemotherapeutics can induce the degradation of SK1, with the loss of this pro-survival enzyme shown to significantly contribute to the anti-cancer properties of these agents. Here we define the mechanistic basis for this degradation of SK1 in response to SK1 inhibitors, chemotherapeutics, and in natural protein turnover. Using an inducible SK1 expression system that enables the degradation of pre-formed SK1 to be assessed independent of transcriptional or translational effects, we found that SK1 was degraded primarily by the proteasome since several proteasome inhibitors blocked SK1 degradation, while lysosome, cathepsin B or pan caspase inhibitors had no effect. Importantly, we demonstrate that this proteasomal degradation of SK1 was enabled by its ubiquitination at Lys183 that appears facilitated by SK1 inhibitor-induced conformational changes in the structure of SK1 around this residue. Furthermore, using yeast two-hybrid screening, we identified Kelch-like protein 5 (KLHL5) as an important protein adaptor linking SK1 to the cullin 3 (Cul3) ubiquitin ligase complex. Notably, knockdown of KLHL5 or Cul3, use of a cullin inhibitor or a dominant-negative Cul3 all attenuated SK1 degradation. Collectively this data demonstrates the KLHL5/Cul3-based E3 ubiquitin ligase complex is important for regulation of SK1 protein stability via Lys183 ubiquitination, in response to SK1 inhibitors, chemotherapy and for normal SK1 protein turnover., (© 2019 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)
- Published
- 2019
- Full Text
- View/download PDF
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