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951.
Erik J.B. Landin Christopher Williams Sara A. Ryan Alice Bochel Nahida Akter Christina Redfield Richard B. Sessions Neesha Dedi Richard J. Taylor Matthew P. Crump 《The Journal of biological chemistry》2021,297(6)
The α1-acid glycoprotein (AGP) is an abundant blood plasma protein with important immunomodulatory functions coupled to endogenous and exogenous ligand-binding properties. Its affinity for many drug-like structures, however, means AGP can have a significant effect on the pharmokinetics and pharmacodynamics of numerous small molecule therapeutics. Staurosporine, and its hydroxylated forms UCN-01 and UCN-02, are kinase inhibitors that have been investigated at length as antitumour compounds. Despite their potency, these compounds display poor pharmokinetics due to binding to both AGP variants, AGP1 and AGP2. The recent renewed interest in UCN-01 as a cytostatic protective agent prompted us to solve the structure of the AGP2–UCN-01 complex by X-ray crystallography, revealing for the first time the precise binding mode of UCN-01. The solution NMR suggests AGP2 undergoes a significant conformational change upon ligand binding, but also that it uses a common set of sidechains with which it captures key groups of UCN-01 and other small molecule ligands. We anticipate that this structure and the supporting NMR data will facilitate rational redesign of small molecules that could evade AGP and therefore improve tissue distribution. 相似文献
952.
Tanner C. Dixon Christina M. Merrick Joni D. Wallis Richard B. Ivry Jose M. Carmena 《PLoS computational biology》2021,17(11)
Pronounced activity is observed in both hemispheres of the motor cortex during preparation and execution of unimanual movements. The organizational principles of bi-hemispheric signals and the functions they serve throughout motor planning remain unclear. Using an instructed-delay reaching task in monkeys, we identified two components in population responses spanning PMd and M1. A “dedicated” component, which segregated activity at the level of individual units, emerged in PMd during preparation. It was most prominent following movement when M1 became strongly engaged, and principally involved the contralateral hemisphere. In contrast to recent reports, these dedicated signals solely accounted for divergence of arm-specific neural subspaces. The other “distributed” component mixed signals for each arm within units, and the subspace containing it did not discriminate between arms at any stage. The statistics of the population response suggest two functional aspects of the cortical network: one that spans both hemispheres for supporting preparatory and ongoing processes, and another that is predominantly housed in the contralateral hemisphere and specifies unilateral output. 相似文献
953.
Frans A Kuypers Christina A Rostad Evan J Anderson Ann Chahroudi Preeti Jaggi Jens Wrammert Grace Mantus Rajit Basu Frank Harris Bradley Hanberry Andres Camacho-Gonzalez Shaminy Manoranjithan Miriam Vos Lou Ann Brown Claudia R Morris 《Experimental biology and medicine (Maywood, N.J.)》2021,246(23):2543
Secretory phospholipase 2 (sPLA2) acts as a mediator between proximal and distal events of the inflammatory cascade. Its role in SARS-CoV-2 infection is unknown, but could contribute to COVID-19 inflammasome activation and cellular damage. We present the first report of plasma sPLA2 levels in adults and children with COVID-19 compared with controls. Currently asymptomatic adults with a history of recent COVID-19 infection (≥4 weeks before) identified by SARS-CoV-2 IgG antibodies had sPLA2 levels similar to those who were seronegative (9 ± 6 vs.17 ± 28 ng/mL, P = 0.26). In contrast, children hospitalized with severe COVID-19 had significantly elevated sPLA2 compared with those with mild or asymptomatic SARS-CoV-2 infection (269 ± 137 vs. 2 ± 3 ng/mL, P = 0.01). Among children hospitalized with multisystem inflammatory syndrome in children (MIS-C), all had severe disease requiring pediatric intensive care unit (PICU) admission. sPLA2 levels were significantly higher in those with acute illness <10 days versus convalescent disease ≥10 days (540 ± 510 vs. 2 ± 1, P = 0.04). Thus, sPLA2 levels correlated with COVID-19 severity and acute MIS-C in children, implicating a role in inflammasome activation and disease pathogenesis. sPLA2 may be a useful biomarker to stratify risk and guide patient management for children with acute COVID-19 and MIS-C. Therapeutic compounds targeting sPLA2 and inflammasome activation warrant consideration. 相似文献
954.
Christina Vogel Sarah Crozier Daniel Penn-Newman Kylie Ball Graham Moon Joanne Lord Cyrus Cooper Janis Baird 《PLoS medicine》2021,18(9)
BackgroundPrevious product placement trials in supermarkets are limited in scope and outcome data collected. This study assessed the effects on store-level sales, household-level purchasing, and dietary behaviours of a healthier supermarket layout.Methods and findingsThis is a prospective matched controlled cluster trial with 2 intervention components: (i) new fresh fruit and vegetable sections near store entrances (replacing smaller displays at the back) and frozen vegetables repositioned to the entrance aisle, plus (ii) the removal of confectionery from checkouts and aisle ends opposite. In this pilot study, the intervention was implemented for 6 months in 3 discount supermarkets in England. Three control stores were matched on store sales and customer profiles and neighbourhood deprivation. Women customers aged 18 to 45 years, with loyalty cards, were assigned to the intervention (n = 62) or control group (n = 88) of their primary store. The trial registration number is . Interrupted time series analysis showed that increases in store-level sales of fruits and vegetables were greater in intervention stores than predicted at 3 (1.71 standard deviations (SDs) (95% CI 0.45, 2.96), P = 0.01) and 6 months follow-up (2.42 SDs (0.22, 4.62), P = 0.03), equivalent to approximately 6,170 and approximately 9,820 extra portions per store, per week, respectively. The proportion of purchasing fruits and vegetables per week rose among intervention participants at 3 and 6 months compared to control participants (0.2% versus −3.0%, P = 0.22; 1.7% versus −3.5%, P = 0.05, respectively). Store sales of confectionery were lower in intervention stores than predicted at 3 (−1.05 SDs (−1.98, −0.12), P = 0.03) and 6 months (−1.37 SDs (−2.95, 0.22), P = 0.09), equivalent to approximately 1,359 and approximately 1,575 fewer portions per store, per week, respectively; no differences were observed for confectionery purchasing. Changes in dietary variables were predominantly in the expected direction for health benefit. Intervention implementation was not within control of the research team, and stores could not be randomised. It is a pilot study, and, therefore, not powered to detect an effect.ConclusionsHealthier supermarket layouts can improve the nutrition profile of store sales and likely improve household purchasing and dietary quality. Placing fruits and vegetables near store entrances should be considered alongside policies to limit prominent placement of unhealthy foods.Trial registrationClinicalTrials.gov NCT03518151 (pre-results)Christina Vogel and colleagues assess the effects of creating a healthier layout in supermarkets in England on store-level sales, household-level purchasing, and dietary behaviors of women customers. NCT03518151相似文献
955.
Jason W. Skudlarek Christina N. DiMarco Kerim Babaoglu Anthony J. Roecker Joseph G. Bruno Mark A. Pausch Julie A. OBrien Tamara D. Cabalu Joanne Stevens Joseph Brunner Pamela L. Tannenbaum W. Peter Wuelfing Susan L. Garson Steven V. Fox Alan T. Savitz Charles M. Harrell Anthony L. Gotter Christopher J. Winrow Paul J. Coleman 《Bioorganic & medicinal chemistry letters》2017,27(6):1364-1370
In an ongoing effort to explore the use of orexin receptor antagonists for the treatment of insomnia, dual orexin receptor antagonists (DORAs) were structurally modified, resulting in compounds selective for the OX2R subtype and culminating in the discovery of 23, a highly potent, OX2R-selective molecule that exhibited a promising in vivo profile. Further structural modification led to an unexpected restoration of OX1R antagonism. Herein, these changes are discussed and a rationale for selectivity based on computational modeling is proposed. 相似文献
956.
Michael Schalli Patrick Weber Christina Tysoe Bettina M. Pabst Martin Thonhofer Eduard Paschke Arnold E. Stütz Marion Tschernutter Werner Windischhofer Stephen G. Withers 《Bioorganic & medicinal chemistry letters》2017,27(15):3431-3435
N-Functionalized amino(hydroxymethyl)cyclopentanetriols are potent inhibitors of β-d-galactosidases and, for the first time, could be shown to act as pharmacological chaperones for GM1-gangliosidosis-associated lysosomal acid β-galactosidase thus representing a new structural type of pharmacological chaperones for this lysosomal storage disease. 相似文献
957.
The bulky and the sweet: How neutralizing antibodies and glycan receptors compete for virus binding
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Christina Harprecht Thilo Stehle 《Protein science : a publication of the Protein Society》2017,26(12):2342-2354
Numerous viruses rely on glycan receptor binding as the initial step in host cell infection. Engagement of specific glycan receptors such as sialylated carbohydrates, glycosaminoglycans, or histo‐blood group antigens can determine host range, tissue tropism, and pathogenicity. Glycan receptor‐binding sites are typically located in exposed regions on viral surfaces—sites that are also generally prone to binding of neutralizing antibodies that directly interfere with virus‐glycan receptor interactions. In this review, we examine the locations and architecture of the glycan‐ and antibody‐binding sites in four different viruses with stalk‐like attachment proteins (reovirus, influenza virus, norovirus, and coronavirus) and investigate the mechanisms by which antibodies block glycan recognition. Those viruses exemplify that direct molecular mimicking of glycan receptors by antibodies is rare and further demonstrate that antibodies often partly overlap or bind sufficiently close to the receptor‐binding region to hinder access to this site, achieving neutralization partially because of the epitope location and partly due to their sheer size. 相似文献
958.
959.
Mate choice screening in captive solitary carnivores: The role of male behavior and cues on mate preference and paternity in females of a model species,American mink (Neovison vison)
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960.
Erica Lana Mahbod Khanbolouki Charline Degavre Eva-Britt Samuelsson Elisabet Åkesson Bengt Winblad Evren Alici Christina Unger Lithner Homira Behbahani 《Molecular neurobiology》2017,54(2):874-887
Studies on the mechanisms of neuronal amyloid-β (Aβ) internalisation are crucial for understanding the neuropathological progression of Alzheimer’s disease (AD). We here investigated how extracellular Aβ peptides are internalised and focused on three different pathways: (i) via endocytic mechanisms, (ii) via the receptor for advanced glycation end products (RAGE) and (iii) via the pore-forming protein perforin. Both Aβ40 and Aβ42 were internalised in retinoic acid differentiated neuroblastoma (RA-SH-SY5Y) cells. A higher concentration was required for Aβ40 (250 nM) compared with Aβ42 (100 nM). The internalised Aβ40 showed a dot-like pattern of distribution whereas Aβ42 accumulated in larger and distinct formations. By confocal microscopy, we showed that Aβ40 and Aβ42 co-localised with mitochondria, endoplasmic reticulum (ER) and lysosomes. Aβ treatment of human primary cortical neurons (hPCN) confirmed our findings in RA-SH-SY5Y cells, but hPCN were less sensitive to Aβ; therefore, a 20 (Aβ40) and 50 (Aβ42) times higher concentration was needed for inducing uptake. The blocking of endocytosis completely inhibited the internalisation of Aβ peptides in RA-SH-SY5Y cells and hPCN, indicating that this is a major pathway by which Aβ enters the cells. In addition, the internalisation of Aβ42, but not Aβ40, was reduced by 55 % by blocking RAGE. Finally, for the first time we showed that pore formation in cell membranes by perforin led to Aβ internalisation in hPCN. Understanding how Aβ is internalised sheds light on the pathological role of Aβ and provides further ideas of inhibitory strategies for preventing Aβ internalisation and the spreading of neurodegeneration in AD. 相似文献