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1.
Nature ; 615(7953): 712-719, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36922590

RESUMO

Mitochondria are critical to the governance of metabolism and bioenergetics in cancer cells1. The mitochondria form highly organized networks, in which their outer and inner membrane structures define their bioenergetic capacity2,3. However, in vivo studies delineating the relationship between the structural organization of mitochondrial networks and their bioenergetic activity have been limited. Here we present an in vivo structural and functional analysis of mitochondrial networks and bioenergetic phenotypes in non-small cell lung cancer (NSCLC) using an integrated platform consisting of positron emission tomography imaging, respirometry and three-dimensional scanning block-face electron microscopy. The diverse bioenergetic phenotypes and metabolic dependencies we identified in NSCLC tumours align with distinct structural organization of mitochondrial networks present. Further, we discovered that mitochondrial networks are organized into distinct compartments within tumour cells. In tumours with high rates of oxidative phosphorylation (OXPHOSHI) and fatty acid oxidation, we identified peri-droplet mitochondrial networks wherein mitochondria contact and surround lipid droplets. By contrast, we discovered that in tumours with low rates of OXPHOS (OXPHOSLO), high glucose flux regulated perinuclear localization of mitochondria, structural remodelling of cristae and mitochondrial respiratory capacity. Our findings suggest that in NSCLC, mitochondrial networks are compartmentalized into distinct subpopulations that govern the bioenergetic capacity of tumours.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Metabolismo Energético , Neoplasias Pulmonares , Mitocôndrias , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/ultraestrutura , Ácidos Graxos/metabolismo , Glucose/metabolismo , Gotículas Lipídicas/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/ultraestrutura , Microscopia Eletrônica , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Fosforilação Oxidativa , Fenótipo , Tomografia por Emissão de Pósitrons
2.
Nature ; 616(7957): 553-562, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37055640

RESUMO

Circulating tumour DNA (ctDNA) can be used to detect and profile residual tumour cells persisting after curative intent therapy1. The study of large patient cohorts incorporating longitudinal plasma sampling and extended follow-up is required to determine the role of ctDNA as a phylogenetic biomarker of relapse in early-stage non-small-cell lung cancer (NSCLC). Here we developed ctDNA methods tracking a median of 200 mutations identified in resected NSCLC tissue across 1,069 plasma samples collected from 197 patients enrolled in the TRACERx study2. A lack of preoperative ctDNA detection distinguished biologically indolent lung adenocarcinoma with good clinical outcome. Postoperative plasma analyses were interpreted within the context of standard-of-care radiological surveillance and administration of cytotoxic adjuvant therapy. Landmark analyses of plasma samples collected within 120 days after surgery revealed ctDNA detection in 25% of patients, including 49% of all patients who experienced clinical relapse; 3 to 6 monthly ctDNA surveillance identified impending disease relapse in an additional 20% of landmark-negative patients. We developed a bioinformatic tool (ECLIPSE) for non-invasive tracking of subclonal architecture at low ctDNA levels. ECLIPSE identified patients with polyclonal metastatic dissemination, which was associated with a poor clinical outcome. By measuring subclone cancer cell fractions in preoperative plasma, we found that subclones seeding future metastases were significantly more expanded compared with non-metastatic subclones. Our findings will support (neo)adjuvant trial advances and provide insights into the process of metastatic dissemination using low-ctDNA-level liquid biopsy.


Assuntos
Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Mutação , Metástase Neoplásica , Carcinoma de Pequenas Células do Pulmão , Humanos , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/genética , Estudos de Coortes , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metástase Neoplásica/diagnóstico , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Filogenia , Carcinoma de Pequenas Células do Pulmão/patologia , Biópsia Líquida
3.
Proc Natl Acad Sci U S A ; 121(20): e2215679121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38709924

RESUMO

Limiting the rise in global temperature to 1.5 °C will rely, in part, on technologies to remove CO2 from the atmosphere. However, many carbon dioxide removal (CDR) technologies are in the early stages of development, and there is limited data to inform predictions of their future adoption. Here, we present an approach to model adoption of early-stage technologies such as CDR and apply it to direct air carbon capture and storage (DACCS). Our approach combines empirical data on historical technology analogs and early adoption indicators to model a range of feasible growth pathways. We use these pathways as inputs to an integrated assessment model (the Global Change Analysis Model, GCAM) and evaluate their effects under an emissions policy to limit end-of-century temperature change to 1.5 °C. Adoption varies widely across analogs, which share different strategic similarities with DACCS. If DACCS growth mirrors high-growth analogs (e.g., solar photovoltaics), it can reach up to 4.9 GtCO2 removal by midcentury, compared to as low as 0.2 GtCO2 for low-growth analogs (e.g., natural gas pipelines). For these slower growing analogs, unabated fossil fuel generation in 2050 is reduced by 44% compared to high-growth analogs, with implications for energy investments and stranded assets. Residual emissions at the end of the century are also substantially lower (by up to 43% and 34% in transportation and industry) under lower DACCS scenarios. The large variation in growth rates observed for different analogs can also point to policy takeaways for enabling DACCS.

4.
Proc Natl Acad Sci U S A ; 121(13): e2215688121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38498705

RESUMO

Equity is core to sustainability, but current interventions to enhance sustainability often fall short in adequately addressing this linkage. Models are important tools for informing action, and their development and use present opportunities to center equity in process and outcomes. This Perspective highlights progress in integrating equity into systems modeling in sustainability science, as well as key challenges, tensions, and future directions. We present a conceptual framework for equity in systems modeling, focused on its distributional, procedural, and recognitional dimensions. We discuss examples of how modelers engage with these different dimensions throughout the modeling process and from across a range of modeling approaches and topics, including water resources, energy systems, air quality, and conservation. Synthesizing across these examples, we identify significant advances in enhancing procedural and recognitional equity by reframing models as tools to explore pluralism in worldviews and knowledge systems; enabling models to better represent distributional inequity through new computational techniques and data sources; investigating the dynamics that can drive inequities by linking different modeling approaches; and developing more nuanced metrics for assessing equity outcomes. We also identify important future directions, such as an increased focus on using models to identify pathways to transform underlying conditions that lead to inequities and move toward desired futures. By looking at examples across the diverse fields within sustainability science, we argue that there are valuable opportunities for mutual learning on how to use models more effectively as tools to support sustainable and equitable futures.

5.
Proc Natl Acad Sci U S A ; 120(14): e2300150120, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36996117

RESUMO

The cell cycle checkpoint kinase Mec1ATR and its integral partner Ddc2ATRIP are vital for the DNA damage and replication stress response. Mec1-Ddc2 "senses" single-stranded DNA (ssDNA) by being recruited to the ssDNA binding Replication Protein A (RPA) via Ddc2. In this study, we show that a DNA damage-induced phosphorylation circuit modulates checkpoint recruitment and function. We demonstrate that Ddc2-RPA interactions modulate the association between RPA and ssDNA and that Rfa1-phosphorylation aids in the further recruitment of Mec1-Ddc2. We also uncover an underappreciated role for Ddc2 phosphorylation that enhances its recruitment to RPA-ssDNA that is important for the DNA damage checkpoint in yeast. The crystal structure of a phosphorylated Ddc2 peptide in complex with its RPA interaction domain provides molecular details of how checkpoint recruitment is enhanced, which involves Zn2+. Using electron microscopy and structural modeling approaches, we propose that Mec1-Ddc2 complexes can form higher order assemblies with RPA when Ddc2 is phosphorylated. Together, our results provide insight into Mec1 recruitment and suggest that formation of supramolecular complexes of RPA and Mec1-Ddc2, modulated by phosphorylation, would allow for rapid clustering of damage foci to promote checkpoint signaling.


Assuntos
Proteína de Replicação A , Proteínas de Saccharomyces cerevisiae , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Dano ao DNA , Replicação do DNA , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteína de Replicação A/genética , Proteína de Replicação A/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
6.
PLoS Pathog ; 19(7): e1011529, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37478143

RESUMO

The genomes of positive-sense RNA viruses encode polyproteins that are essential for mediating viral replication. These viral polyproteins must undergo proteolysis (also termed polyprotein processing) to generate functional protein units. This proteolysis can be performed by virally-encoded proteases as well as host cellular proteases, and is generally believed to be a key step in regulating viral replication. Hepatitis E virus (HEV) is a leading cause of acute viral hepatitis. The positive-sense RNA genome is translated to generate a polyprotein, termed pORF1, which is necessary and sufficient for viral genome replication. However, the mechanism of polyprotein processing in HEV remains to be determined. In this study, we aimed to understand processing of this polyprotein and its role in viral replication using a combination of in vitro translation experiments and HEV sub-genomic replicons. Our data suggest no evidence for a virally-encoded protease or auto-proteolytic activity, as in vitro translation predominantly generates unprocessed viral polyprotein precursors. However, seven cleavage sites within the polyprotein (suggested by bioinformatic analysis) are susceptible to the host cellular protease, thrombin. Using two sub-genomic replicon systems, we demonstrate that mutagenesis of these sites prevents replication, as does pharmacological inhibition of serine proteases including thrombin. Overall, our data supports a model where HEV uses host proteases to support replication and could have evolved to be independent of a virally-encoded protease for polyprotein processing.


Assuntos
Vírus da Hepatite E , Vírus da Hepatite E/genética , Poliproteínas/genética , Poliproteínas/metabolismo , Trombina , Replicação Viral/fisiologia , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Proteínas não Estruturais Virais/metabolismo
7.
FASEB J ; 38(14): e23822, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39072864

RESUMO

Secondary and tertiary RNA structures play key roles in genome replication of single-stranded positive sense RNA viruses. Complex, functional structures are particularly abundant in the untranslated regions of picornaviruses, where they are involved in initiation of translation, priming of new strand synthesis and genome circularization. The 5' UTR of foot-and-mouth disease virus (FMDV) is predicted to include a c. 360 nucleotide-long stem-loop, termed the short (S) fragment. This structure is highly conserved and essential for viral replication, but the precise function(s) are unclear. Here, we used selective 2' hydroxyl acetylation analyzed by primer extension (SHAPE) to experimentally determine aspects of the structure, alongside comparative genomic analyses to confirm structure conservation from a wide range of field isolates. To examine its role in virus replication in cell culture, we introduced a series of deletions to the distal and proximal regions of the stem-loop. These truncations affected genome replication in a size-dependent and, in some cases, host cell-dependent manner. Furthermore, during the passage of viruses incorporating the largest tolerated deletion from the proximal region of the S fragment stem-loop, an additional mutation was selected in the viral RNA-dependent RNA polymerase, 3Dpol. These data suggest that the S fragment and 3Dpol interact in the formation of the FMDV replication complex.


Assuntos
Vírus da Febre Aftosa , Conformação de Ácido Nucleico , RNA Viral , Replicação Viral , Vírus da Febre Aftosa/genética , Vírus da Febre Aftosa/fisiologia , Replicação Viral/genética , RNA Viral/genética , RNA Viral/metabolismo , Animais , Regiões 5' não Traduzidas , Febre Aftosa/virologia , Genoma Viral , Linhagem Celular , Cricetinae
8.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35042803

RESUMO

Green plants play a fundamental role in ecosystems, human health, and agriculture. As de novo genomes are being generated for all known eukaryotic species as advocated by the Earth BioGenome Project, increasing genomic information on green land plants is essential. However, setting standards for the generation and storage of the complex set of genomes that characterize the green lineage of life is a major challenge for plant scientists. Such standards will need to accommodate the immense variation in green plant genome size, transposable element content, and structural complexity while enabling research into the molecular and evolutionary processes that have resulted in this enormous genomic variation. Here we provide an overview and assessment of the current state of knowledge of green plant genomes. To date fewer than 300 complete chromosome-scale genome assemblies representing fewer than 900 species have been generated across the estimated 450,000 to 500,000 species in the green plant clade. These genomes range in size from 12 Mb to 27.6 Gb and are biased toward agricultural crops with large branches of the green tree of life untouched by genomic-scale sequencing. Locating suitable tissue samples of most species of plants, especially those taxa from extreme environments, remains one of the biggest hurdles to increasing our genomic inventory. Furthermore, the annotation of plant genomes is at present undergoing intensive improvement. It is our hope that this fresh overview will help in the development of genomic quality standards for a cohesive and meaningful synthesis of green plant genomes as we scale up for the future.


Assuntos
Sequência de Bases/genética , Genômica/tendências , Viridiplantae/genética , Biodiversidade , Evolução Biológica , Elementos de DNA Transponíveis/genética , Ecologia , Ecossistema , Embriófitas/genética , Evolução Molecular , Genoma , Genoma de Planta/genética , Genômica/métodos , Disseminação de Informação/métodos , Armazenamento e Recuperação da Informação/métodos , Filogenia , Plantas/genética
9.
Proc Natl Acad Sci U S A ; 119(12): e2114380119, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35298332

RESUMO

SignificanceSkin is recognized as an intricate assembly of molecular components, which facilitate cell signaling, metabolism, and protein synthesis mechanisms in order to offer protection, regulation, and sensation to the body. Our study takes significant steps to characterize in more detail the complex chemistry of the skin, in particular by generating a better understanding of the uppermost layer, the stratum corneum. Using a state-of-the-art 3D OrbiSIMS technique, we were able to observe the depth distribution, in situ, for a wide range of molecular species. This unprecedented molecular characterization of skin provides information that has the potential to benefit research into fundamental processes, such as those associated with skin aging and disease, and the development and delivery of effective topical formulations.


Assuntos
Epiderme , Envelhecimento da Pele , Epiderme/metabolismo , Pele/metabolismo , Absorção Cutânea
10.
J Am Chem Soc ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38848551

RESUMO

We present millisecond quantitative serial X-ray crystallography at 1.7 Å resolution demonstrating precise optical control of reversible population transfer from Trans-Cis and Cis-Trans photoisomerization of a reversibly switchable fluorescent protein, rsKiiro. Quantitative results from the analysis of electron density differences, extrapolated structure factors, and occupancy refinements are shown to correspond to optical measurements of photoinduced population transfer and have sensitivity to a few percent in concentration differences. Millisecond time-resolved concentration differences are precisely and reversibly controlled through intense continuous wave laser illuminations at 405 and 473 nm for the Trans-to-Cis and Cis-to-Trans reactions, respectively, while the X-ray crystallographic measurement and laser illumination of the metastable Trans chromophore conformation causes partial thermally driven reconversion across a 91.5 kJ/mol thermal barrier from which a temperature jump between 112 and 128 K is extracted.

11.
Oncologist ; 29(4): 356-363, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37676048

RESUMO

BACKGROUND: Since the onset of COVID-19, oncology practices across the US have integrated telemedicine (TM) and remote patient monitoring (RPM) into routine care and clinical trials. The extent of provider experience and comfort with TM/RPM in treatment trials, however, is unknown. We surveyed oncology researchers to assess experience and comfort with TM/RPM. METHODS: Between April 10 and June 1, 2022, we distributed email surveys to US-based members of the American Society of Clinical Oncology (ASCO) whose member records indicated interest or specialization in clinical research. We collected respondent demographic data, clinical trial experience, workplace characteristics, and comfort and experience with TM/RPM use across trial components in phase I and phase II/III trials. TM/RPM was defined as clinical trial-related healthcare and monitoring for patients geographically separated from trial site. RESULTS: There were 141 surveys analyzed (5.1% response rate). Ninety percent of respondents had been Principal Investigators, 98% practiced in a norural site. Most respondents had enrolled patients in phase I (82%) and phase II/III trials (99%). Across all phases and trial components, there was a higher frequency of researcher comfort compared to experience. Regarding remote care in treatment trials, 75% reported using TM, RPM, or both. Among these individuals, 62% had never provided remote care to trial patients before the pandemic. CONCLUSION: COVID-19 spurred the rise of TM/RPM in cancer treatment trials, and some TM/RPM use continues in this context. Among oncology researchers, higher levels of comfort compared with real-world experience with TM/RPM reveal opportunities for expanding TM/RPM policies and guidelines in oncology research.


Assuntos
COVID-19 , Neoplasias , Telemedicina , Humanos , COVID-19/epidemiologia , Atenção à Saúde , Oncologia , Monitorização Fisiológica , Neoplasias/terapia
12.
Anal Chem ; 96(29): 11760-11770, 2024 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-38989551

RESUMO

Growing clinical evidence reveals that systematic molecular alterations in the brain occur 20 years before the onset of AD pathological features. Apolipoprotein E4 (ApoE4) is one of the most significant genetic risk factors for Alzheimer's disease (AD), which is not only associated with the AD pathological features such as amyloid-ß deposition, phosphorylation of tau proteins, and neuroinflammation but is also involved in metabolism, neuron growth, and synaptic plasticity. Multiomics, such as metabolomics and proteomics, are applied widely in identifying key disease-related molecular alterations and disease-progression-related changes. Despite recent advances in the development of analytical technologies, screening the entire profile of metabolites remains challenging due to the numerous classes of compounds with diverse chemical properties that require different extraction processes for mass spectrometry. In this study, we utilized Orbitrap Secondary Ion Mass Spectrometry (OrbiSIMS) as a chemical filtering screening tool to examine molecular alterations in ApoE4-carried neuroglioma cells compared to wild-type H4 cells. The findings were compared using liquid chromatography (LC)-MS/MS targeted metabolomics analysis for the confirmation of specific metabolite classes. Detected alterations in peptide fragments by OrbiSIMS provided preliminary indications of protein changes. These were extensively analyzed through proteomics to explore ApoE4's impact on proteins. Our metabolomics approach, combining OrbiSIMS and LC-MS/MS, revealed disruptions in lipid metabolism, including glycerophospholipids and sphingolipids, as well as amino acid metabolism, encompassing alanine, aspartate, and glutamate metabolism; aminoacyl-tRNA biosynthesis; glutamine metabolism; and taurine and hypotaurine metabolism. Further LC-MS/MS proteomics studies confirmed the dysfunction in amino acid and tRNA aminoacylation metabolic processes, and highlighted RNA splicing alterations influenced by ApoE4.


Assuntos
Doença de Alzheimer , Apolipoproteína E4 , Metabolômica , Proteômica , Espectrometria de Massas em Tandem , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Humanos , Apolipoproteína E4/metabolismo , Apolipoproteína E4/genética , Cromatografia Líquida , Metabolômica/métodos , Glioma/metabolismo , Glioma/patologia , Linhagem Celular Tumoral , Espectrometria de Massa com Cromatografia Líquida
13.
RNA ; 28(10): 1359-1376, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35918125

RESUMO

Genome replication of positive strand RNA viruses requires the production of a complementary negative strand RNA that serves as a template for synthesis of more positive strand progeny. Structural RNA elements are important for genome replication, but while they are readily observed in the positive strand, evidence of their existence in the negative strand is more limited. We hypothesized that this was due to viruses differing in their capacity to allow this latter RNA to adopt structural folds. To investigate this, ribozymes were introduced into the negative strand of different viral constructs; the expectation being that if RNA folding occurred, negative strand cleavage and suppression of replication would be seen. Indeed, this was what happened with hepatitis C virus (HCV) and feline calicivirus (FCV) constructs. However, little or no impact was observed for chikungunya virus (CHIKV), human rhinovirus (HRV), hepatitis E virus (HEV), and yellow fever virus (YFV) constructs. Reduced cleavage in the negative strand proved to be due to duplex formation with the positive strand. Interestingly, ribozyme-containing RNAs also remained intact when produced in vitro by the HCV polymerase, again due to duplex formation. Overall, our results show that there are important differences in the conformational constraints imposed on the folding of the negative strand between different positive strand RNA viruses.


Assuntos
Hepatite C , RNA Catalítico , Hepacivirus/genética , Humanos , Vírus de RNA de Cadeia Positiva , RNA Catalítico/genética , RNA Viral/genética , Replicação Viral/genética
14.
J Virol ; 97(5): e0017123, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-37154761

RESUMO

Foot-and-mouth disease virus (FMDV) is a picornavirus, which infects cloven-hoofed animals to cause foot-and-mouth disease (FMD). The positive-sense RNA genome contains a single open reading frame, which is translated as a polyprotein that is cleaved by viral proteases to produce the viral structural and nonstructural proteins. Initial processing occurs at three main junctions to generate four primary precursors; Lpro and P1, P2, and P3 (also termed 1ABCD, 2BC, and 3AB1,2,3CD). The 2BC and 3AB1,2,3CD precursors undergo subsequent proteolysis to generate the proteins required for viral replication, including the enzymes 2C, 3Cpro, and 3Dpol. These precursors can be processed through both cis and trans (i.e., intra- and intermolecular proteolysis) pathways, which are thought to be important for controlling virus replication. Our previous studies suggested that a single residue in the 3B3-3C junction has an important role in controlling 3AB1,2,3CD processing. Here, we use in vitro based assays to show that a single amino acid substitution at the 3B3-3C boundary increases the rate of proteolysis to generate a novel 2C-containing precursor. Complementation assays showed that while this amino acid substitution enhanced production of some nonenzymatic nonstructural proteins, those with enzymatic functions were inhibited. Interestingly, replication could only be supported by complementation with mutations in cis acting RNA elements, providing genetic evidence for a functional interaction between replication enzymes and RNA elements. IMPORTANCE Foot-and-mouth disease virus (FMDV) is responsible for foot-and-mouth disease (FMD), an important disease of farmed animals, which is endemic in many parts of the world and can results in major economic losses. Replication of the virus occurs within membrane-associated compartments in infected cells and requires highly coordinated processing events to produce an array of nonstructural proteins. These are initially produced as a polyprotein that undergoes proteolysis likely through both cis and trans alternative pathways (i.e., intra- and intermolecular proteolysis). The role of alternative processing pathways may help coordination of viral replication by providing temporal control of protein production and here we analyze the consequences of amino acid substitutions that change these pathways in FMDV. Our data suggest that correct processing is required to produce key enzymes for replication in an environment in which they can interact with essential viral RNA elements. These data further the understanding of RNA genome replication.


Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Animais , Vírus da Febre Aftosa/metabolismo , Poliproteínas/genética , Poliproteínas/metabolismo , Replicação Viral/genética , Proteínas não Estruturais Virais/metabolismo , RNA/metabolismo
15.
J Virol ; 97(12): e0171923, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38032199

RESUMO

IMPORTANCE: All viruses initiate infection by utilizing receptors to attach to target host cells. These virus-receptor interactions can therefore dictate viral replication and pathogenesis. Understanding the nature of virus-receptor interactions could also be important for the development of novel therapies. Noroviruses are non-enveloped icosahedral viruses of medical importance. They are a common cause of acute gastroenteritis with no approved vaccine or therapy and are a tractable model for studying fundamental virus biology. In this study, we utilized the murine norovirus model system to show that variation in a single amino acid of the major capsid protein alone can affect viral infectivity through improved attachment to suspension cells. Modulating plasma membrane mobility reduced infectivity, suggesting an importance of membrane mobility for receptor recruitment and/or receptor conformation. Furthermore, different substitutions at this site altered viral tissue distribution in a murine model, illustrating how in-host capsid evolution could influence viral infectivity and/or immune evasion.


Assuntos
Infecções por Caliciviridae , Proteínas do Capsídeo , Norovirus , Animais , Camundongos , Substituição de Aminoácidos , Infecções por Caliciviridae/metabolismo , Capsídeo/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Evasão da Resposta Imune , Norovirus/metabolismo , Proteínas do Core Viral/metabolismo
16.
PLoS Pathog ; 18(6): e1010589, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35666744

RESUMO

Non-coding regions of viral RNA (vRNA) genomes are critically important in the regulation of gene expression. In particular, pseudoknot (PK) structures, which are present in a wide range of RNA molecules, have a variety of roles. The 5' untranslated region (5' UTR) of foot-and-mouth disease virus (FMDV) vRNA is considerably longer than in other viruses from the picornavirus family and consists of a number of distinctive structural motifs that includes multiple (2, 3 or 4 depending on the virus strain) putative PKs linked in tandem. The role(s) of the PKs in the FMDV infection are not fully understood. Here, using bioinformatics, sub-genomic replicons and recombinant viruses we have investigated the structural conservation and importance of the PKs in the FMDV lifecycle. Our results show that despite the conservation of two or more PKs across all FMDVs, a replicon lacking PKs was replication competent, albeit at reduced levels. Furthermore, in competition experiments, GFP FMDV replicons with less than two (0 or 1) PK structures were outcompeted by a mCherry FMDV wt replicon that had 4 PKs, whereas GFP replicons with 2 or 4 PKs were not. This apparent replicative advantage offered by the additional PKs correlates with the maintenance of at least two PKs in the genomes of FMDV field isolates. Despite a replicon lacking any PKs retaining the ability to replicate, viruses completely lacking PK were not viable and at least one PK was essential for recovery of infections virus, suggesting a role for the PKs in virion assembly. Thus, our study points to roles for the PKs in both vRNA replication and virion assembly, thereby improving understanding the molecular biology of FMDV replication and the wider roles of PK in RNA functions.


Assuntos
Vírus da Febre Aftosa , Febre Aftosa , Regiões 5' não Traduzidas , Animais , Vírus de DNA , Febre Aftosa/genética , Vírus da Febre Aftosa/genética , Genoma Viral , RNA Viral/química , Replicação Viral/genética
17.
J Pediatr ; 269: 113997, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38432293

RESUMO

OBJECTIVE: To evaluate trends of attention-deficit/hyperactivity disorder (ADHD) diagnosis rates among children aged 5-17 years over the past decade (2010-2021) and to investigate whether there have been differences in temporal changes based on race and ethnicity, sex, or income. STUDY DESIGN: Childhood ADHD diagnosis was ascertained from electronic health records using International Classification of Diseases ninth revision (314.xx) and International Classification of Diseases tenth revision (F90.x) codes. Data were stratified by child's sex, race and ethnicity, and household income, and rates of ADHD were estimated before and after adjustment for potential confounders. RESULTS: The overall ADHD diagnosis rates increased from 3.5% in 2010 to 4.0% in 2021. ADHD diagnosis was most prevalent among White children (6.1%), then Black (4.6%), Other/multiple (3.7%), Hispanic (3.1%), and Asian/Pacific Islander (PI) (1.7%). ADHD was also highly prevalent among boys (73.3%) or family income≥$70,000 (50.0%). ADHD diagnosis increased among Black (4.2% to 5.1%), Hispanic (2.8% to 3.6%), and Asian/PI children (1.5% to 2.0%) but remained stable for White (6.2% to 6.1%) and Other/multiple race/ethnic children (3.7% to 3.7%). Increases in the prevalence among girls were also observed. CONCLUSION: The prevalence of ADHD in children has risen with the largest increases observed for Black, Hispanic, and Asian/PI children. Rates among less affluent families and girls have also been increasing, narrowing the gaps in diagnosis rates previously observed. These increases may reflect improvements in screening and provision of care among demographics where ADHD has been historically underdiagnosed.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Prestação Integrada de Cuidados de Saúde , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Criança , Masculino , Feminino , Adolescente , Pré-Escolar , California/epidemiologia , Prevalência
18.
Ann Surg Oncol ; 2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39003378

RESUMO

Contemporary trend analysis of a large national data set confirms the occurrence of a significant shift toward minimally invasive nephroureterectomy (MINU), which is gradually replacing open nephroureterectomy (ONU). A minimally invasive approach is associated with a lower risk of complications. Social determinants of health (SDOH) are non-clinical factors that ultimately may have an impact on the outcomes of the nephroureterectomy (NU) procedure ( https://doi.org/10.1245/s10434-024-15565-6 ).

19.
Ann Surg Oncol ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879671

RESUMO

BACKGROUND: It is generally perceived that minimally invasive nephroureterectomy (MINU), especially in the form of robotic-assisted laparoscopy, is gaining an increasing role in many institutions. OBJECTIVE: The aim of our study was to investigate contemporary trends in the adoption of MINU in the United States compared with open nephroureterectomy (ONU). METHODS: Patients who underwent ONU or MINU between 2011 and 2021 were retrospectively analyzed using PearlDiver Mariner, an all-payer insurance claims database. International Classification of Diseases diagnosis and procedure codes were used to identify the type of surgical procedure, patients' characteristics, social determinants of health (SDOH), and perioperative complications. The primary objective assessed different trends and costs in NU adoption, while secondary objectives analyzed factors influencing the postoperative complications, including SDOH. Outcomes were compared using multivariable regression models. RESULTS: Overall, 15,240 patients underwent ONU (n = 7675) and MINU (n = 7565). Utilization of ONU declined over the study period, whereas that of MINU increased from 29 to 72% (p = 0.01). The 60-day postoperative complication rate was 23% for ONU and 19% for MINU (p < 0.001). At multivariable analysis, ONU showed a significantly higher risk of postoperative complications (odds ratio 1.33, 95% CI 1.20-1.48). Approximately 5% and 9% of patients reported at least one SDOH at baseline for both ONU and MINU (p < 0.001). CONCLUSIONS: Contemporary trend analysis of a large national dataset confirms that there has been a significant shift towards MINU, which is gradually replacing ONU. A minimally invasive approach is associated with lower risk of complications. SDOH are non-clinical factors that currently do not have an impact on the outcomes of nephroureterectomy.

20.
Nat Chem Biol ; 18(6): 596-604, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35314814

RESUMO

Current small-molecule inhibitors of KRAS(G12C) bind irreversibly in the switch-II pocket (SII-P), exploiting the strong nucleophilicity of the acquired cysteine as well as the preponderance of the GDP-bound form of this mutant. Nevertheless, many oncogenic KRAS mutants lack these two features, and it remains unknown whether targeting the SII-P is a practical therapeutic approach for KRAS mutants beyond G12C. Here we use NMR spectroscopy and a cellular KRAS engagement assay to address this question by examining a collection of SII-P ligands from the literature and from our own laboratory. We show that the SII-Ps of many KRAS hotspot (G12, G13, Q61) mutants are accessible using noncovalent ligands, and that this accessibility is not necessarily coupled to the GDP state of KRAS. The results we describe here emphasize the SII-P as a privileged drug-binding site on KRAS and unveil new therapeutic opportunities in RAS-driven cancer.


Assuntos
Mieloma Múltiplo , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Ligantes , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética
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