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Kimani RW
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Reexamining the use of race in medical algorithms: the maternal health calcul...

FRONTIERS IN PUBLIC HEALTH 2024 JUN 13; 12(?):? Article 1417429
The concept of race is prevalent in medical, nursing, and public health literature. Clinicians often incorporate race into diagnostics, prognostic tools, and treatment guidelines. An example is the recently heavily debated use of race and ethnicity in the Vaginal Birth After Cesarean (VBAC) calculator. In this case, the critics argued that the use of race in this calculator implied that race confers immutable characteristics that affect the ability of women to give birth vaginally after a c-section. This debate is co-occurring as research continues to highlight the racial disparities in health outcomes, such as high maternal mortality among Black women compared to other racial groups in the United States. As the healthcare system contemplates the necessity of utilizing race-a social and political construct, to monitor health outcomes, it has sparked more questions about incorporating race into clinical algorithms, including pulmonary tests, kidney function tests, pharmacotherapies, and genetic testing. This paper critically examines the argument against the race-based Vaginal Birth After Cesarean (VBAC) calculator, shedding light on its implications. Moreover, it delves into the detrimental effects of normalizing race as a biological variable, which hinders progress in improving health outcomes and equity.
Lee U, Mozeika SM, Zhao L
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A Synergistic, Cultivator Model of De Novo Gene Origination

GENOME BIOLOGY AND EVOLUTION 2024 JUN 5; 16(6):? Article evae103
The origin and fixation of evolutionarily young genes is a fundamental question in evolutionary biology. However, understanding the origins of newly evolved genes arising de novo from noncoding genomic sequences is challenging. This is partly due to the low likelihood that several neutral or nearly neutral mutations fix prior to the appearance of an important novel molecular function. This issue is particularly exacerbated in large effective population sizes where the effect of drift is small. To address this problem, we propose a regulation-focused, cultivator model for de novo gene evolution. This cultivator-focused model posits that each step in a novel variant's evolutionary trajectory is driven by well-defined, selectively advantageous functions for the cultivator genes, rather than solely by the de novo genes, emphasizing the critical role of genome organization in the evolution of new genes.
Lee J, Oldham ML, Manon V, Chen J
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Principles of peptide selection by the transporter associated with antigen pr...

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2024 JUN 4; 121(23):? Article e2320879121
Our ability to fight pathogens relies on major histocompatibility complex class I (MHC - I) molecules presenting diverse antigens on the surface of diseased cells. The transporter associated with antigen processing (TAP) transports nearly the entire repertoire of antigenic peptides into the endoplasmic reticulum for MHC - I loading. How TAP transports peptides specific for MHC - I is unclear. In this study, we used cryo - EM to determine a series of structures of human TAP, both in the absence and presence of peptides with various sequences and lengths. The structures revealed that peptides of eight or nine residues in length bind in a similarly extended conformation, despite having little sequence overlap. We also identified two peptide - anchoring pockets on either side of the transmembrane cavity, each engaging one end of a peptide with primarily main chain atoms. Occupation of both pockets results in a global conformational change in TAP, bringing the two halves of the transporter closer together to prime it for isomerization and ATP hydrolysis. Shorter peptides are able to bind to each pocket separately but are not long enough to bridge the cavity to bind to both simultaneously. Mutations that disrupt hydrogen bonds with the N and C termini of peptides almost abolish MHC - I surface expression. Our findings reveal that TAP functions as a molecular caliper that selects peptides according to length rather than sequence, providing antigen diversity for MHC - I presentation.
Lyu JK, Kapolka N, Gumpper R, Alon A, Wang L, Jain MK, Barros-Alvarez X, Saka...
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AlphaFold2 structures guide prospective ligand discovery

SCIENCE 2024 JUN 21; 384(6702):1316-+ Article eadn6354
AlphaFold2 (AF2) models have had wide impact but mixed success in retrospective ligand recognition. We prospectively docked large libraries against unrefined AF2 models of the sigma(2) and serotonin 2A (5-HT2A) receptors, testing hundreds of new molecules and comparing results with those obtained from docking against the experimental structures. Hit rates were high and similar for the experimental and AF2 structures, as were affinities. Success in docking against the AF2 models was achieved despite differences between orthosteric residue conformations in the AF2 models and the experimental structures. Determination of the cryo-electron microscopy structure for one of the more potent 5-HT2A ligands from the AF2 docking revealed residue accommodations that resembled the AF2 prediction. AF2 models may sample conformations that differ from experimental structures but remain low energy and relevant for ligand discovery, extending the domain of structure-based drug design.
Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, ...
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Combined search for electroweak production of winos, binos, higgsinos, and sl...

PHYSICAL REVIEW D 2024 JUN 6; 109(11):? Article 112001
A combination of the results of several searches for the electroweak production of the supersymmetric partners of standard model bosons, and of charged leptons, is presented. All searches use proton-proton collision data at root s = 13 TeV recorded with the CMS detector at the LHC in 2016-2018. The analyzed data correspond to an integrated luminosity of up to 137 fb(-1). The results are interpreted in terms of simplified models of supersymmetry. Two new interpretations are added with this combination: a model spectrum with the bino as the lightest supersymmetric particle together with mass-degenerate Higgsinos decaying to the bino and a standard model boson, and the compressed-spectrum region of a previously studied model of slepton pair production. Improved analysis techniques are employed to optimize sensitivity for the compressed spectra in the wino and slepton pair production models. The results are consistent with expectations from the standard model. The combination provides a more comprehensive coverage of the model parameter space than the individual searches, extending the exclusion by up to 125 GeV, and also targets some of the intermediate gaps in the mass coverage.
Short B
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The S1 helix is a VIP in VSP

JOURNAL OF GENERAL PHYSIOLOGY 2024 JUN 11; 156(7):? Article e202413612
JGP study shows that hydrophobic residues in the S1 transmembrane domain modulate the voltage-sensor movements and enzymatic activity of voltage-sensing phosphatase.
Hayrapetyan A, Tumasyan A, Adam W, Andrejkovic JW, Bergauer T, Chatterjee S, ...
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Combination of Measurements of the Top Quark Mass from Data Collected by the ...

PHYSICAL REVIEW LETTERS 2024 JUN 27; 132(26):? Article 261902
A combination of fifteen top quark mass measurements performed by the ATLAS and CMS experiments at the LHC is presented. The datasets used correspond to an integrated luminosity of up to 5 and 20 fb(-1) of proton-proton collisions at center-of-mass energies of 7 and 8 TeV, respectively. The combination includes measurements in top quark pair events that exploit both the semileptonic and hadronic decays of the top quark, and a measurement using events enriched in single top quark production via the electroweak t channel. The combination accounts for the correlations between measurements and achieves an improvement in the total uncertainty of 31% relative to the most precise input measurement. The result is m(t) = 172.52 +/- 0.14(stat) +/- 0.30(stat) GeV, with a total uncertainty of 0.33 GeV.
Jones NH, Liu QW, Urnavicius L, Dahan NE, Vostal LE, Kapoor TM, Arkin MR, Che...
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Allosteric activation of VCP, an AAA unfoldase, by small molecule mimicry

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2024 JUN 11; 121(24):? Article e2316892121
The loss of function of AAA (ATPases associated with diverse cellular activities) mechanoenzymes has been linked to diseases, and small molecules that activate these proteins can be powerful tools to probe mechanisms and test therapeutic hypotheses. Unlike chemical inhibitors that can bind a single conformational state to block enzyme function, activator binding must be permissive to different conformational states needed for mechanochemistry. However, we do not know how AAA proteins can be activated by small molecules. Here, we focus on valosin-containing protein (VCP)/p97, an AAA unfoldase whose loss of function has been linked to protein aggregation-based disorders, to identify druggable sites for chemical activators. We identified VCP ATPase Activator 1 (VAA1), a compound that dose-dependently stimulates VCP ATPase activity up to similar to threefold. Our cryo-EM studies resulted in structures (ranging from similar to 2.9 to 3.7 angstrom-resolution) of VCP in apo and ADP-bound states and revealed that VAA1 binds an allosteric pocket near the C-terminus in both states. Engineered mutations in the VAA1-binding site confer resistance to VAA1, and furthermore, modulate VCP activity. Mutation of a phenylalanine residue in the VCP C-terminal tail that can occupy the VAA1 binding site also stimulates ATPase activity, suggesting that VAA1 acts by mimicking this interaction. Together, our findings uncover a druggable allosteric site and a mechanism of enzyme regulation that can be tuned through small molecule mimicry.
Ramos EA, Kiszka JJ, Reiss D, Magnasco MO
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Coastal dolphins provide foraging opportunities to benthic-feeding seabirds i...

BEHAVIOUR 2024 JUN; 161(6):495-503
In marine ecosystems, predators can affect community and ecosystem dynamics through a variety of processes such as foraging facilitation. Here, we report evidence of foraging facilitation between common bottlenose dolphins (Tursiops truncatus) and double-crested cormorants (Nannopterum auritum) in the Caribbean seagrass-dominated atoll of Turneffe, Belize using aerial drone observations conducted in 2015-2017. While dolphins exhibited occasional aggressive behaviours toward the cormorants, the latter frequently followed dolphin movements, suggesting opportunistic pursuit of dolphins for prey access during dolphin bottom foraging activity. Our observations underscore the intricate ecological relationships among marine predators and highlight the need to quantify the mutual benefits and costs of such interactions as coastal ecosystems are rapidly changing.
Zeledon EV, Baxt LA, Khan TA, Michino M, Miller M, Huggins DJ, Jiang CS, Voss...
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Next-generation neuropeptide Y receptor small-molecule agonists inhibit mosqu...

PARASITES & VECTORS 2024 JUN 28; 17(1):? Article 276
Background Female Aedes aegypti mosquitoes can spread disease-causing pathogens when they bite humans to obtain blood nutrients required for egg production. Following a complete blood meal, host-seeking is suppressed until eggs are laid. Neuropeptide Y-like receptor 7 (NPYLR7) plays a role in endogenous host-seeking suppression and previous work identified small-molecule NPYLR7 agonists that inhibit host-seeking and blood-feeding when fed to mosquitoes at high micromolar doses. Methods Using structure-activity relationship analysis and structure-guided design we synthesized 128 compounds with similarity to known NPYLR7 agonists. Results Although in vitro potency (EC50) was not strictly predictive of in vivo effect, we identified three compounds that reduced blood-feeding from a live host when fed to mosquitoes at a dose of 1 mu M-a 100-fold improvement over the original reference compound. Conclusions Exogenous activation of NPYLR7 represents an innovative vector control strategy to block mosquito biting behavior and prevent mosquito-human host interactions that lead to pathogen transmission.