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1.
Nature ; 626(8001): 1125-1132, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38355796

RESUMO

To conserve energy during starvation and stress, many organisms use hibernation factor proteins to inhibit protein synthesis and protect their ribosomes from damage1,2. In bacteria, two families of hibernation factors have been described, but the low conservation of these proteins and the huge diversity of species, habitats and environmental stressors have confounded their discovery3-6. Here, by combining cryogenic electron microscopy, genetics and biochemistry, we identify Balon, a new hibernation factor in the cold-adapted bacterium Psychrobacter urativorans. We show that Balon is a distant homologue of the archaeo-eukaryotic translation factor aeRF1 and is found in 20% of representative bacteria. During cold shock or stationary phase, Balon occupies the ribosomal A site in both vacant and actively translating ribosomes in complex with EF-Tu, highlighting an unexpected role for EF-Tu in the cellular stress response. Unlike typical A-site substrates, Balon binds to ribosomes in an mRNA-independent manner, initiating a new mode of ribosome hibernation that can commence while ribosomes are still engaged in protein synthesis. Our work suggests that Balon-EF-Tu-regulated ribosome hibernation is a ubiquitous bacterial stress-response mechanism, and we demonstrate that putative Balon homologues in Mycobacteria bind to ribosomes in a similar fashion. This finding calls for a revision of the current model of ribosome hibernation inferred from common model organisms and holds numerous implications for how we understand and study ribosome hibernation.


Assuntos
Proteínas de Bactérias , Resposta ao Choque Frio , Fatores de Terminação de Peptídeos , Biossíntese de Proteínas , Psychrobacter , Proteínas Ribossômicas , Ribossomos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/ultraestrutura , Fator Tu de Elongação de Peptídeos/química , Fator Tu de Elongação de Peptídeos/metabolismo , Fator Tu de Elongação de Peptídeos/ultraestrutura , Proteínas Ribossômicas/química , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Proteínas Ribossômicas/ultraestrutura , Ribossomos/química , Ribossomos/metabolismo , Ribossomos/ultraestrutura , Psychrobacter/química , Psychrobacter/genética , Psychrobacter/metabolismo , Psychrobacter/ultraestrutura , Microscopia Crioeletrônica , Fatores de Terminação de Peptídeos/química , Fatores de Terminação de Peptídeos/genética , Fatores de Terminação de Peptídeos/metabolismo , Fatores de Terminação de Peptídeos/ultraestrutura
2.
Nature ; 622(7984): 712-717, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37880437

RESUMO

The detection of deep reflected S waves on Mars inferred a core size of 1,830 ± 40 km (ref. 1), requiring light-element contents that are incompatible with experimental petrological constraints. This estimate assumes a compositionally homogeneous Martian mantle, at odds with recent measurements of anomalously slow propagating P waves diffracted along the core-mantle boundary2. An alternative hypothesis is that Mars's mantle is heterogeneous as a consequence of an early magma ocean that solidified to form a basal layer enriched in iron and heat-producing elements. Such enrichment results in the formation of a molten silicate layer above the core, overlain by a partially molten layer3. Here we show that this structure is compatible with all geophysical data, notably (1) deep reflected and diffracted mantle seismic phases, (2) weak shear attenuation at seismic frequency and (3) Mars's dissipative nature at Phobos tides. The core size in this scenario is 1,650 ± 20 km, implying a density of 6.5 g cm-3, 5-8% larger than previous seismic estimates, and can be explained by fewer, and less abundant, alloying light elements than previously required, in amounts compatible with experimental and cosmochemical constraints. Finally, the layered mantle structure requires external sources to generate the magnetic signatures recorded in Mars's crust.

3.
Proc Natl Acad Sci U S A ; 120(1): e2212175120, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36574699

RESUMO

The ability of bacterial pathogens to adapt to host niches is driven by the carriage and regulation of genes that benefit pathogenic lifestyles. Genes that encode virulence or fitness-enhancing factors must be regulated in response to changing host environments to allow rapid response to challenges presented by the host. Furthermore, this process can be controlled by preexisting transcription factors (TFs) that acquire new roles in tailoring regulatory networks, specifically in pathogens. However, the mechanisms underlying this process are poorly understood. The highly conserved Escherichia coli TF YhaJ exhibits distinct genome-binding dynamics and transcriptome control in pathotypes that occupy different host niches, such as uropathogenic E. coli (UPEC). Here, we report that this important regulator is required for UPEC systemic survival during murine bloodstream infection (BSI). This advantage is gained through the coordinated regulation of a small regulon comprised of both virulence and metabolic genes. YhaJ coordinates activation of both Type 1 and F1C fimbriae, as well as biosynthesis of the amino acid tryptophan, by both direct and indirect mechanisms. Deletion of yhaJ or the individual genes under its control leads to attenuated survival during BSI. Furthermore, all three systems are up-regulated in response to signals derived from serum or systemic host tissue, but not urine, suggesting a niche-specific regulatory trigger that enhances UPEC fitness via pleiotropic mechanisms. Collectively, our results identify YhaJ as a pathotype-specific regulatory aide, enhancing the expression of key genes that are collectively required for UPEC bloodstream pathogenesis.


Assuntos
Infecções por Escherichia coli , Proteínas de Escherichia coli , Sepse , Infecções Urinárias , Escherichia coli Uropatogênica , Animais , Camundongos , Escherichia coli/genética , Escherichia coli/metabolismo , Infecções Urinárias/microbiologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Fatores de Virulência/genética , Escherichia coli Uropatogênica/genética , Regulação Bacteriana da Expressão Gênica
4.
PLoS Genet ; 19(6): e1010784, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37276233

RESUMO

Competitive bacteria-bacteriophage interactions have resulted in the evolution of a plethora of bacterial defense systems preventing phage propagation. In recent years, computational and bioinformatic approaches have underpinned the discovery of numerous novel bacterial defense systems. Anti-phage systems are frequently encoded together in genomic loci termed defense islands. Here we report the identification and characterisation of a novel anti-phage system, that we have termed Shield, which forms part of the Pseudomonas defensive arsenal. The Shield system comprises the core component ShdA, a membrane-bound protein harboring an RmuC domain. Heterologous production of ShdA alone is sufficient to mediate bacterial immunity against several phages. We demonstrate that Shield and ShdA confer population-level immunity and that they can also decrease transformation efficiency. We further show that ShdA homologues can degrade DNA in vitro and, when expressed in a heterologous host, can alter the organisation of the host chromosomal DNA. Use of comparative genomic approaches identified how Shield can be divided into four subtypes, three of which contain additional components that in some cases can negatively affect the activity of ShdA and/or provide additional lines of phage defense. Collectively, our results identify a new player within the Pseudomonas bacterial immunity arsenal that displays a novel mechanism of protection, and reveals a role for RmuC domains in phage defense.


Assuntos
Bacteriófagos , Bacteriófagos/genética , Pseudomonas/genética , Bactérias/genética , Genoma
6.
Proc Natl Acad Sci U S A ; 119(45): e2210299119, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36322762

RESUMO

Ecologically beneficial traits in bacteria are encoded by intrinsic and horizontally acquired genes. However, such traits are not universal, and the highly mosaic nature of bacterial genomes requires control at the transcriptional level to drive these processes. It has emerged that regulatory flexibility is widespread in the Escherichia coli species, whereby preexisting transcription factors can acquire new and unrelated roles in regulating beneficial traits. DsdC is the regulator of D-serine tolerance in E. coli, is essential for D-serine catabolism, and is often encoded by two copies in neonatal meningitis-associated E. coli (NMEC). Here, we reveal that DsdC is a global regulator of transcription in NMEC and does not require D-serine for the control of novel beneficial traits. We show that DsdC binds the chromosome in an unusual manner, with many binding sites arranged in clusters spanning entire operons and within gene coding sequences, such as neuO. Importantly, we identify neuO as the most significantly down-regulated gene in a strain deleted for both dsdC copies, in both the presence and absence of D-serine. NeuO is prophage encoded in several NMEC K1 isolates and mediates capsule O-acetylation but has no effect on attachment to or invasion of human brain endothelial cells. Instead, we demonstrate that NeuO provides resistance against K1 bacteriophage attack and that this critical function is regulated by DsdC. This work highlights how a horizontally acquired enzyme that functions in cell-surface modulation can be controlled by an intrinsic regulator to provide a key ecological benefit to an E. coli pathotype.


Assuntos
Bacteriófagos , Proteínas de Escherichia coli , Recém-Nascido , Humanos , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Bacteriófagos/metabolismo , Células Endoteliais/metabolismo , Serina/metabolismo
7.
CA Cancer J Clin ; 67(4): 290-303, 2017 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-28294295

RESUMO

Answer questions and earn CME/CNE The revision of the eighth edition of the primary tumor, lymph node, and metastasis (TNM) classification of the American Joint Commission of Cancer (AJCC) for breast cancer was determined by a multidisciplinary team of breast cancer experts. The panel recognized the need to incorporate biologic factors, such as tumor grade, proliferation rate, estrogen and progesterone receptor expression, human epidermal growth factor 2 (HER2) expression, and gene expression prognostic panels into the staging system. AJCC levels of evidence and guidelines for all tumor types were followed as much as possible. The panel felt that, to maintain worldwide value, the tumor staging system should remain based on TNM anatomic factors. However, the recognition of the prognostic influence of grade, hormone receptor expression, and HER2 amplification mandated their inclusion into the staging system. The value of commercially available, gene-based assays was acknowledged and prognostic input added. Tumor biomarkers and low Oncotype DX recurrence scores can alter prognosis and stage. These updates are expected to provide additional precision and flexibility to the staging system and were based on the extent of published information and analysis of large, as yet unpublished databases. The eighth edition of the AJCC TNM staging system, thus, provides a flexible platform for prognostic classification based on traditional anatomic factors, which can be modified and enhanced using patient biomarkers and multifactorial prognostic panel data. The eighth edition remains the worldwide basis for breast cancer staging and will incorporate future online updates to remain timely and relevant. CA Cancer J Clin 2017;67:290-303. © 2017 American Cancer Society.


Assuntos
Neoplasias da Mama/patologia , Estadiamento de Neoplasias/métodos , Biomarcadores Tumorais , Neoplasias da Mama/classificação , Feminino , Humanos , Metástase Linfática , Metástase Neoplásica , Guias de Prática Clínica como Assunto , Prognóstico , Estados Unidos
8.
Dig Dis Sci ; 69(2): 360-369, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38041763

RESUMO

BACKGROUND: Fecal immunochemical test (FIT) is less effective in detecting advanced adenomas (AA) than colonoscopy. Increase in FIT for colorectal cancer (CRC) screening may lead to an increased number of undetected AAs which may develop into future CRCs. AIM: We determined the potential impact of FIT expansion on missed AAs and future CRC diagnoses in an urban, tertiary-care, safety-net hospital. METHODS: CRC and AA diagnoses were identified in patients undergoing colonoscopy for average-risk CRC screening or positive FIT between 2017 and 2019 at Boston Medical Center. Poisson regression modeling was used to estimate the frequency of AAs per year by age group using data from 2017 to 2019, assuming average outpatient volume and proportion of screening colonoscopies. Total number of patients who received FIT was extrapolated from those who underwent colonoscopy for positive FIT. We estimated AAs per year if 'one-time' FIT was used for screening in 75% and 100% of the population and subtracted this from the estimated AAs per year under the Poisson model to determine missed AAs. We used previously described, age and gender specific estimates of the annual progression of AA to CRC. RESULTS: The estimated number of CRCs detected per year is 4.6/1785 males and 4.6/2086 females screened. With 75% FIT expansion, we estimate an additional 3.5 (95% CI 1.3, 9.5) and 2.2 (95% CI 0.64, 7.6) CRCs; with 100% FIT expansion, we estimate an additional 7.4 (95% CI 3.7, 14.9) and 4.2 (95% CI 1.7, 10.5) CRCs, in 5 years, in males and females, respectively. CONCLUSION: Expansion of FIT may substantially increase CRC incidence.


Assuntos
Colonoscopia , Neoplasias Colorretais , Masculino , Feminino , Humanos , Programas de Rastreamento , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Sangue Oculto , Detecção Precoce de Câncer , Fezes
9.
Mol Pharm ; 20(8): 4086-4099, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37466053

RESUMO

The effects of atomic layer (ALC) coating on physical properties and storage stability were examined in solid powders containing myoglobin, a model protein. Powders containing myoglobin and mannitol (1:1 w/w) were prepared by lyophilization or spray drying and subjected to aluminum oxide or silicon oxide ALC coating. Uncoated samples of these powders as well as coated and uncoated samples of myoglobin as received served as controls. After preparation (t0), samples were analyzed for moisture content, reconstitution time, myoglobin secondary structure, crystallinity, and protein aggregate content. Samples were stored for 3 months (t3) under controlled conditions (53% RH, 40 °C) in both open and closed vials and then analyzed as above. At t3, the recovery of soluble native (i.e., monomeric) protein depended on formulation, coating type, and drying method and was up to 2-fold greater in coated samples than in uncoated controls. Promisingly, some samples with high recovery also showed low soluble aggregate content (<10%) at t3 and low total monomer loss; the latter was correlated to sample moisture content. Overall, the results demonstrate that ALC coatings can stabilize solid protein formulations during storage, providing benefits over uncoated controls.


Assuntos
Mioglobina , Mioglobina/química , Pós/química , Liofilização , Estrutura Secundária de Proteína , Estabilidade de Medicamentos
10.
Proc Natl Acad Sci U S A ; 117(36): 22484-22493, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32848072

RESUMO

The molecular environment of the host can have profound effects on the behavior of resident bacterial species. We recently established how the sensing and response of enterohemorrhagic Escherichia coli (EHEC) to d-serine (d-Ser) resulted in down-regulation of type 3 secretion system-dependent colonization, thereby avoiding unfavorable environments abundant in this toxic metabolite. However, this model ignores a key determinant of the success of bacterial pathogens, adaptive evolution. In this study, we have explored the adaptation of EHEC to d-Ser and its consequences for pathogenesis. We rapidly isolated multiple, independent, EHEC mutants whose growth was no longer compromised in the presence of d-Ser. Through a combination of whole-genome sequencing and transcriptomics, we showed that tolerance could be attributed to disruption of one of two d-Ser transporters and/or activation of a previously nonfunctional d-Ser deaminase. While the implication of cytoplasmic transport in d-Ser toxicity was unsurprising, disruption of a single transporter, CycA, was sufficient to completely overcome the repression of type 3 secretion system activity normally associated with exposure to d-Ser. Despite the fact that this reveals a mechanism by which evolution could drive a pathogen to colonize new niches, interrogation of sequenced E. coli O157:H7 genomes showed a high level of CycA conservation, highlighting a strong selective pressure for functionality. Collectively, these data show that CycA is a critically important conduit for d-Ser uptake that is central to the niche restriction of EHEC.


Assuntos
Escherichia coli Êntero-Hemorrágica , Genoma Bacteriano , Serina/farmacologia , Adaptação Biológica/genética , Escherichia coli Êntero-Hemorrágica/efeitos dos fármacos , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/metabolismo , Técnicas de Silenciamento de Genes , Genoma Bacteriano/efeitos dos fármacos , Genoma Bacteriano/genética , Células HeLa , Humanos , Mutação/genética , Sistemas de Secreção Tipo III/genética
11.
J Appl Clin Med Phys ; 24(6): e13932, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36794436

RESUMO

ICRU 91, published in 2017, is an international standard for prescribing, recording, and reporting stereotactic treatments. Since its release, there has been limited research published on the implementation and impact of ICRU 91 on clinical practice. This work provides an assessment of the recommended ICRU 91 dose reporting metrics for their use in clinical treatment planning. A set of 180 intracranial stereotactic treatment plans for patients treated by the CyberKnife (CK) system were analyzed retrospectively using the ICRU 91 reporting metrics. The 180 plans comprised 60 trigeminal neuralgia (TGN), 60 meningioma (MEN), and 60 acoustic neuroma (AN) cases. The reporting metrics included the planning target volume (PTV) near-minimum dose ( D near - min ${D}_{{\rm{near}} - {\rm{min}}}$ ), near-maximum dose ( D near - max ${D}_{{\rm{near}} - {\rm{max}}}$ ), and median dose ( D 50 % ${D}_{50{\rm{\% }}}$ ), as well as the gradient index (GI) and conformity index (CI). The metrics were assessed for statistical correlation with several treatment plan parameters. In the TGN plan group, owing to the small targets, D near - min ${D}_{{\rm{near}} - {\rm{min}}}$ was greater than D near - max ${D}_{{\rm{near}} - {\rm{max}}}$ in 42 plans, whereas both metrics were not applicable in 17 plans. The D 50 % ${D}_{50{\rm{\% }}}$ metric was predominantly influenced by the prescription isodose line (PIDL). The GI was significantly dependent on target volume in all analyses performed, where the variables were inversely related. The CI was only dependent on target volume in treatment plans for small targets. The ICRU 91 D near - min ${D}_{{\rm{near}} - {\rm{min}}}$ and D near - max ${D}_{{\rm{near}} - {\rm{max}}}$ metrics breakdown in plans for small target volumes below 1 cm3 ; the Min and Max pixel should be reported in such cases. The D 50 % ${D}_{50{\rm{\% }}}$ metric is of limited use for treatment planning. Given their volume dependence, the GI and CI metrics could potentially serve as plan evaluation tools in the planning of the sites analyzed in this study, which would ultimately improve treatment plan quality.


Assuntos
Neuroma Acústico , Radiocirurgia , Humanos , Estudos Retrospectivos , Neuroma Acústico/radioterapia , Neuroma Acústico/cirurgia , Benchmarking , Planejamento da Radioterapia Assistida por Computador , Dosagem Radioterapêutica
12.
Ultraschall Med ; 44(1): 36-49, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36228630

RESUMO

OBJECTIVE: To evaluate the evidence and produce a summary and recommendations for the most common heart and lung point-of-care ultrasound (PoCUS). METHODS: We reviewed 10 clinical domains/questions related to common heart and lung applications of PoCUS. Following review of the evidence, a summary and recommendations were produced, including assigning levels of evidence (LoE) and grading of recommendation, assessment, development, and evaluation (GRADE). 38 international experts, the expert review group (ERG), were invited to review the evidence presented for each question. A level of agreement of over 75 % was required to progress to the next section. The ERG then reviewed and indicated their level of agreement of the summary and recommendation for each question (using a 5-point Likert scale), which was approved in the case of a level of agreement of greater than 75 %. A level of agreement was defined as a summary of "strongly agree" and "agree" on the Likert scale responses. FINDINGS AND RECOMMENDATIONS: One question achieved a strong consensus for an assigned LoE of 3 and a weak GRADE recommendation (question 1), the remaining 9 questions achieved broad agreement with an assigned LoE of 4 and a weak GRADE recommendation (question 2), three achieved an LoE of 3 with a weak GRADE recommendation (questions 3-5), three achieved an LoE of 3 with a strong GRADE recommendation (questions 6-8) and the remaining two were assigned an LoE of 2 with a strong GRADE recommendation (questions 9 and 10). CONCLUSION: These consensus-derived recommendations should aid clinical practice and highlight areas of further research for PoCUS in acute settings.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Testes Imediatos , Humanos , Pulmão , Ultrassonografia
13.
Ultraschall Med ; 44(1): e1-e24, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36228631

RESUMO

AIMS: To evaluate the evidence and produce a summary and recommendations for the most common heart and lung applications of point-of-care ultrasound (PoCUS). METHODS: We reviewed 10 clinical domains/questions related to common heart and lung applications of PoCUS. Following review of the evidence, a summary and recommendation were produced, including assignment of levels of evidence (LoE) and grading of the recommendation, assessment, development, and evaluation (GRADE). 38 international experts, the expert review group (ERG), were invited to review the evidence presented for each question. A level of agreement of over 75 % was required to progress to the next section. The ERG then reviewed and indicated their level of agreement regarding the summary and recommendation for each question (using a 5-point Likert scale), which was approved if a level of agreement of greater than 75 % was reached. A level of agreement was defined as a summary of "strongly agree" and "agree" on the Likert scale responses. FINDINGS AND RECOMMENDATIONS: One question achieved a strong consensus for an assigned LoE of 3 and a weak GRADE recommendation (question 1). The remaining 9 questions achieved broad agreement with one assigned an LoE of 4 and weak GRADE recommendation (question 2), three achieving an LoE of 3 with a weak GRADE recommendation (questions 3-5), three achieved an LoE of 3 with a strong GRADE recommendation (questions 6-8), and the remaining two were assigned an LoE of 2 with a strong GRADE recommendation (questions 9 and 10). CONCLUSION: These consensus-derived recommendations should aid clinical practice and highlight areas of further research for PoCUS in acute settings.


Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Testes Imediatos , Humanos , Pulmão , Ultrassonografia
14.
Rural Remote Health ; 23(1): 8140, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36802673

RESUMO

Introduction (including aim): Axial spondyloarthritis (axSpA) is a chronic inflammatory and rheumatic disease that causes inflammation and structural changes to the skeleton. Patients with axSpA suffer from neck pain and stiffness and have severe and permanent restrictions in movement. Patients are advised to carry out prescribed exercises to maintain mobility, but most do not comply with this advice due to the unnatural nature of head and neck stretching exercises. Clinicians currently only test cervical rotation of patients with axSpA a few times per year. Pain and stiffness can fluctuate between appointments, and there is a need to accurately measure the patient's spinal mobility at home. METHODS: Virtual Reality (VR) headsets have been proven to be accurate and reliable when measuring neck movement. We are using VR to aid relaxation and promote mindfulness, whilst moving the participant's head to visual and auditory cues to enable completion of exercises. In this ongoing study, we are testing whether a smartphone-enabled VR system could be feasible for the measurement of cervical movement at home. RESULTS: The ongoing research will have a positive impact on the lives of patients suffering from axSpA. Regular measurement and assessment of spinal mobility at home will be beneficial to patients and clinicians for objective mobility measurement. DISCUSSION: Implementing VR as both a distractive and rehabilitation encouragement technique could improve patient engagement whilst simultaneously collecting granular mobility data. Additionally, implementing VR rehabilitation using smartphone technology will offer an inexpensive method of exercise and effective rehabilitation.


Assuntos
Espondiloartrite Axial , Medicina , Realidade Virtual , Humanos , Dor , Exercício Físico
15.
Hist Human Sci ; 36(2): 105-127, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37153716

RESUMO

The disruptions to everyday life wrought by the COVID-19 pandemic include distortions in the experience of time, as reported widely by ordinary citizens and observed by journalists and social scientists. But how does this temporal disruption play out in different time scales-in the individual day as opposed to the medium- and long-term futures? And how might place influence how individuals experience and understand the pandemic's temporal transformations? This essay examines a range of temporal disruptions reported in day diaries and surveys submitted to the Everyday Life in Middletown project, an online archive that has been documenting ordinary life in Muncie, Indiana, USA since 2016. Viewing these materials as instances of life writing, the essay probes the interactions between temporal disruptions and the local setting as they inflect the autobiographical selves our writers construct in their pandemic writings. It shows how living in Muncie-a postindustrial city with its particular combination of historical, demographic, economic, social, and political dynamics-structures the autobiographical stories available to our writers, and how the disruption of time produces new variations and problems for life writing. In the midst of a global crisis, we glimpse the pandemic's reshaping of a local structure of feeling in which a pervasive, local narrative of civic decline frames individual self-fashioning.

16.
Radiology ; 303(3): 664-672, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35230187

RESUMO

Background A preoperative predictive model is needed that can be used to identify patients with lung adenocarcinoma (LUAD) who have a higher risk of recurrence or metastasis. Purpose To investigate associations between CT-based radiomic consensus clustering of stage I LUAD and clinical-pathologic features, genomic data, and patient outcomes. Materials and Methods Patients who underwent complete surgical resection for LUAD from April 2014 to December 2017 with preoperative CT and next-generation sequencing data were retrospectively identified. Comprehensive radiomic analysis was performed on preoperative CT images; tumors were classified as solid, ground glass, or mixed. Patients were clustered into groups based on their radiomics features using consensus clustering, and clusters were compared with tumor genomic alterations, histopathologic features, and recurrence-specific survival (Kruskal-Wallis test for continuous data, χ2 or Fisher exact test for categorical data, and log-rank test for recurrence-specific survival). Cluster analysis was performed on the entire cohort and on the solid, ground-glass, and mixed lesion subgroups. Results In total, 219 patients were included in the study (median age, 68 years; interquartile range, 63-74 years; 150 [68%] women). Four radiomic clusters were identified. Cluster 1 was associated with lepidic, acinar, and papillary subtypes (76 of 90 [84%]); clusters 2 (13 of 50 [26%]) and 4 (13 of 45 [29%]) were associated with solid and micropapillary subtypes (P < .001). The EGFR alterations were highest in cluster 1 (38 of 90 [42%], P = .004). Clusters 2, 3, and 4 were associated with lymphovascular invasion (19 of 50 [38%], 14 of 34 [41%], and 28 of 45 [62%], respectively; P < .001) and tumor spread through air spaces (32 of 50 [64%], 21 of 34 [62%], and 31 of 45 [69%], respectively; P < .001). STK11 alterations (14 of 45 [31%]; P = .006), phosphoinositide 3-kinase pathway alterations (22 of 45 [49%], P < .001), and risk of recurrence (log-rank P < .001) were highest in cluster 4. Conclusion CT-based radiomic consensus clustering enabled identification of associations between radiomic features and clinicalpathologic and genomic features and outcomes in patients with clinical stage I lung adenocarcinoma. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Nishino in this issue.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/diagnóstico por imagem , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Idoso , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
17.
Nature ; 539(7629): 420-424, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27853207

RESUMO

The chemistry of aqueous fluids controls the transport and exchange-the cycles-of metals and volatile elements on Earth. Subduction zones, where oceanic plates sink into the Earth's interior, are the most important geodynamic setting for this fluid-mediated chemical exchange. Characterizing the ionic speciation and pH of fluids equilibrated with rocks at subduction zone conditions has long been a major challenge in Earth science. Here we report thermodynamic predictions of fluid-rock equilibria that tie together models of the thermal structure, mineralogy and fluid speciation of subduction zones. We find that the pH of fluids in subducted crustal lithologies is confined to a mildly alkaline range, modulated by rock volatile and chlorine contents. Cold subduction typical of the Phanerozoic eon favours the preservation of oxidized carbon in subducting slabs. In contrast, the pH of mantle wedge fluids is very sensitive to minor variations in rock composition. These variations may be caused by intramantle differentiation, or by infiltration of fluids enriched in alkali components extracted from the subducted crust. The sensitivity of pH to soluble elements in low abundance in the host rocks, such as carbon, alkali metals and halogens, illustrates a feedback between the chemistry of the Earth's atmosphere-ocean system and the speciation of subduction zone fluids via the composition of the seawater-altered oceanic lithosphere. Our findings provide a perspective on the controlling reactions that have coupled metal and volatile cycles in subduction zones for more than 3 billion years7.

18.
Proc Natl Acad Sci U S A ; 116(39): 19695-19704, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31501343

RESUMO

Tailoring transcriptional regulation to coordinate the expression of virulence factors in tandem with the core genome is a hallmark of bacterial pathogen evolution. Bacteria encode hundreds of transcription factors forming the base-level control of gene regulation. Moreover, highly homologous regulators are assumed to control conserved genes between members within a species that harbor the same genetic targets. We have explored this concept in 2 Escherichia coli pathotypes that employ distinct virulence mechanisms that facilitate specification of a different niche within the host. Strikingly, we found that the transcription factor YhaJ actively regulated unique gene sets between intestinal enterohemorrhagic E. coli (EHEC) and extraintestinal uropathogenic E. coli (UPEC), despite being very highly conserved. In EHEC, YhaJ directly activates expression of type 3 secretion system components and effectors. Alternatively, YhaJ enhances UPEC virulence regulation by binding directly to the phase-variable type 1 fimbria promoter, driving its expression. Additionally, YhaJ was found to override the universal GAD acid tolerance system but exclusively in EHEC, thereby indirectly enhancing type 3 secretion pleiotropically. These results have revealed that within a species, conserved regulators are actively repurposed in a "personalized" manner to benefit particular lifestyles and drive virulence via multiple distinct mechanisms.


Assuntos
Escherichia coli/genética , Fatores de Transcrição/genética , Fatores de Virulência/genética , Bactérias/genética , Bactérias/patogenicidade , Escherichia coli Êntero-Hemorrágica/genética , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo III/metabolismo , Escherichia coli Uropatogênica/metabolismo , Virulência/genética
19.
Sensors (Basel) ; 22(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35336401

RESUMO

Data gloves capable of measuring finger joint kinematics can provide objective range of motion information useful for clinical hand assessment and rehabilitation. Data glove sensors are strategically placed over specific finger joints to detect movement of the wearers' hand. The construction of the sensors used in a data glove, the number of sensors used, and their positioning on each finger joint are influenced by the intended use case. Although most glove sensors provide reasonably stable linear output, this stability is influenced externally by the physical structure of the data glove sensors, as well as the wearer's hand size relative to the data glove, and the elastic nature of materials used in its construction. Data gloves typically require a complex calibration method before use. Calibration may not be possible when wearers have disabled hands or limited joint flexibility, and so limits those who can use a data glove within a clinical context. This paper examines and describes a unique approach to calibration and angular calculation using a neural network that improves data glove repeatability and accuracy measurements without the requirement for data glove calibration. Results demonstrate an overall improvement in data glove measurements. This is particularly relevant when the data glove is used with those who have limited joint mobility and cannot physically complete data glove calibration.


Assuntos
Articulações dos Dedos , Mãos , Fenômenos Biomecânicos , Redes Neurais de Computação , Amplitude de Movimento Articular
20.
Microbiology (Reading) ; 167(3)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33529149

RESUMO

The sixth Young Microbiologists Symposium on 'Microbe Signalling, Organisation and Pathogenesis' was scheduled to be held at the University of Southampton, UK, in late August 2020. However, due to the health and safety guidelines and travel restrictions as a response to the COVID-19 pandemic, the symposium was transitioned to a virtual format, a change embraced enthusiastically as the meeting attracted over 200 microbiologists from 40 countries. The event allowed junior scientists to present their work to a broad audience and was supported by the European Molecular Biology Organization, the Federation of European Microbiological Societies, the Society of Applied Microbiology, the Biochemical Society, the Microbiology Society and the National Biofilms Innovation Centre. Sessions covered recent advances in all areas of microbiology including: Secretion and transport across membranes, Gene regulation and signalling, Host-microbe interactions, and Microbial communities and biofilm formation. This report focuses on several of the highlights and exciting developments communicated during the talks and poster presentations.


Assuntos
Interações Hospedeiro-Patógeno , Interações Microbianas , Microbiologia/tendências , Biofilmes , Congressos como Assunto , Humanos , Reino Unido , Comunicação por Videoconferência
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