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1.
Nature ; 615(7953): 640-645, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36890233

RESUMEN

The Devonian-Carboniferous transition marks a fundamental shift in the surface environment primarily related to changes in ocean-atmosphere oxidation states1,2, resulting from the continued proliferation of vascular land plants that stimulated the hydrological cycle and continental weathering3,4, glacioeustasy5,6, eutrophication and anoxic expansion in epicontinental seas3,4, and mass extinction events2,7,8. Here we present a comprehensive spatial and temporal compilation of geochemical data from 90 cores across the entire Bakken Shale (Williston Basin, North America). Our dataset allows for the detailed documentation of stepwise transgressions of toxic euxinic waters into the shallow oceans that drove a series of Late Devonian extinction events. Other Phanerozoic extinctions have also been related to the expansion of shallow-water euxinia, indicating that hydrogen sulfide toxicity was a key driver of Phanerozoic biodiversity.


Asunto(s)
Extinción Biológica , Sulfuro de Hidrógeno , Océanos y Mares , Oxígeno , Análisis Espacio-Temporal , Biodiversidad , Sulfuro de Hidrógeno/análisis , Sulfuro de Hidrógeno/envenenamiento , Atmósfera/química , Ciclo Hidrológico , Eutrofización , Conjuntos de Datos como Asunto , Oxígeno/análisis , Oxígeno/metabolismo , Oxidación-Reducción , Plantas/metabolismo , América del Norte , Historia Antigua , Sedimentos Geológicos/química , Animales
2.
Nature ; 602(7897): 481-486, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34942632

RESUMEN

Humans have infected a wide range of animals with SARS-CoV-21-5, but the establishment of a new natural animal reservoir has not been observed. Here we document that free-ranging white-tailed deer (Odocoileus virginianus) are highly susceptible to infection with SARS-CoV-2, are exposed to multiple SARS-CoV-2 variants from humans and are capable of sustaining transmission in nature. Using real-time PCR with reverse transcription, we detected SARS-CoV-2 in more than one-third (129 out of 360, 35.8%) of nasal swabs obtained from O. virginianus in northeast Ohio in the USA during January to March 2021. Deer in six locations were infected with three SARS-CoV-2 lineages (B.1.2, B.1.582 and B.1.596). The B.1.2 viruses, dominant in humans in Ohio at the time, infected deer in four locations. We detected probable deer-to-deer transmission of B.1.2, B.1.582 and B.1.596 viruses, enabling the virus to acquire amino acid substitutions in the spike protein (including the receptor-binding domain) and ORF1 that are observed infrequently in humans. No spillback to humans was observed, but these findings demonstrate that SARS-CoV-2 viruses have been transmitted in wildlife in the USA, potentially opening new pathways for evolution. There is an urgent need to establish comprehensive 'One Health' programmes to monitor the environment, deer and other wildlife hosts globally.


Asunto(s)
Animales Salvajes/virología , COVID-19/veterinaria , Ciervos/virología , Filogenia , SARS-CoV-2/aislamiento & purificación , Zoonosis Virales/transmisión , Zoonosis Virales/virología , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , COVID-19/epidemiología , COVID-19/transmisión , Evolución Molecular , Humanos , Masculino , Ohio/epidemiología , Salud Única/tendencias , SARS-CoV-2/química , SARS-CoV-2/clasificación , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Zoonosis Virales/epidemiología
3.
Nature ; 592(7854): 444-449, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33762736

RESUMEN

Nonalcoholic steatohepatitis (NASH) is a manifestation of systemic metabolic disease related to obesity, and causes liver disease and cancer1,2. The accumulation of metabolites leads to cell stress and inflammation in the liver3, but mechanistic understandings of liver damage in NASH are incomplete. Here, using a preclinical mouse model that displays key features of human NASH (hereafter, NASH mice), we found an indispensable role for T cells in liver immunopathology. We detected the hepatic accumulation of CD8 T cells with phenotypes that combined tissue residency (CXCR6) with effector (granzyme) and exhaustion (PD1) characteristics. Liver CXCR6+ CD8 T cells were characterized by low activity of the FOXO1 transcription factor, and were abundant in NASH mice and in patients with NASH. Mechanistically, IL-15 induced FOXO1 downregulation and CXCR6 upregulation, which together rendered liver-resident CXCR6+ CD8 T cells susceptible to metabolic stimuli (including acetate and extracellular ATP) and collectively triggered auto-aggression. CXCR6+ CD8 T cells from the livers of NASH mice or of patients with NASH had similar transcriptional signatures, and showed auto-aggressive killing of cells in an MHC-class-I-independent fashion after signalling through P2X7 purinergic receptors. This killing by auto-aggressive CD8 T cells fundamentally differed from that by antigen-specific cells, which mechanistically distinguishes auto-aggressive and protective T cell immunity.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Hígado/inmunología , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/inmunología , Enfermedad del Hígado Graso no Alcohólico/patología , Receptores CXCR6/inmunología , Acetatos/farmacología , Animales , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/patología , Muerte Celular/efectos de los fármacos , Muerte Celular/inmunología , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Humanos , Interleucina-15/inmunología , Interleucina-15/farmacología , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL
4.
PLoS Pathog ; 20(4): e1012131, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38626244

RESUMEN

Patterns of within-host influenza A virus (IAV) diversity and evolution have been described in natural human infections, but these patterns remain poorly characterized in non-human hosts. Elucidating these dynamics is important to better understand IAV biology and the evolutionary processes that govern spillover into humans. Here, we sampled an IAV outbreak in pigs during a week-long county fair to characterize viral diversity and evolution in this important reservoir host. Nasal wipes were collected on a daily basis from all pigs present at the fair, yielding up to 421 samples per day. Subtyping of PCR-positive samples revealed the co-circulation of H1N1 and H3N2 subtype swine IAVs. PCR-positive samples with robust Ct values were deep-sequenced, yielding 506 sequenced samples from a total of 253 pigs. Based on higher-depth re-sequenced data from a subset of these initially sequenced samples (260 samples from 168 pigs), we characterized patterns of within-host IAV genetic diversity and evolution. We find that IAV genetic diversity in single-subtype infected pigs is low, with the majority of intrahost Single Nucleotide Variants (iSNVs) present at frequencies of <10%. The ratio of the number of nonsynonymous to the number of synonymous iSNVs is significantly lower than under the neutral expectation, indicating that purifying selection shapes patterns of within-host viral diversity in swine. The dynamic turnover of iSNVs and their pronounced frequency changes further indicate that genetic drift also plays an important role in shaping IAV populations within pigs. Taken together, our results highlight similarities in patterns of IAV genetic diversity and evolution between humans and swine, including the role of stochastic processes in shaping within-host IAV dynamics.


Asunto(s)
Flujo Genético , Infecciones por Orthomyxoviridae , Enfermedades de los Porcinos , Animales , Porcinos , Infecciones por Orthomyxoviridae/virología , Enfermedades de los Porcinos/virología , Subtipo H3N2 del Virus de la Influenza A/genética , Virus de la Influenza A/genética , Subtipo H1N1 del Virus de la Influenza A/genética , Variación Genética , Evolución Molecular , Selección Genética , Filogenia
5.
Nucleic Acids Res ; 52(12): 6994-7011, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38828775

RESUMEN

The clinical success of PARP1/2 inhibitors (PARPi) prompts the expansion of their applicability beyond homologous recombination deficiency. Here, we demonstrate that the loss of the accessory subunits of DNA polymerase epsilon, POLE3 and POLE4, sensitizes cells to PARPi. We show that the sensitivity of POLE4 knockouts is not due to compromised response to DNA damage or homologous recombination deficiency. Instead, POLE4 loss affects replication speed leading to the accumulation of single-stranded DNA gaps behind replication forks upon PARPi treatment, due to impaired post-replicative repair. POLE4 knockouts elicit elevated replication stress signaling involving ATR and DNA-PK. We find POLE4 to act parallel to BRCA1 in inducing sensitivity to PARPi and counteracts acquired resistance associated with restoration of homologous recombination. Altogether, our findings establish POLE4 as a promising target to improve PARPi driven therapies and hamper acquired PARPi resistance.


Asunto(s)
Proteína BRCA1 , ADN Polimerasa II , Replicación del ADN , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Humanos , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , ADN Polimerasa II/metabolismo , ADN Polimerasa II/genética , Replicación del ADN/efectos de los fármacos , Daño del ADN , Línea Celular Tumoral , Recombinación Homóloga/genética , Recombinación Homóloga/efectos de los fármacos , Resistencia a Antineoplásicos/genética
6.
J Virol ; 98(3): e0004224, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38376198

RESUMEN

Influenza D virus (IDV) utilizes bovines as a primary reservoir with periodical spillover to other hosts. We have previously demonstrated that IDV binds both 9-O-acetylated N-acetylneuraminic acid (Neu5,9Ac2) and 9-O-acetylated N-glycolylneuraminic acid (Neu5Gc9Ac). Bovines produce both Neu5,9Ac2 and Neu5Gc9Ac, while humans are genetically unable to synthesize Neu5Gc9Ac. 9-O-Acetylation of sialic acids is catalyzed by CASD1 via a covalent acetyl-enzyme intermediate. To characterize the role of Neu5,9Ac2 and Neu5Gc9Ac in IDV infection and determine which form of 9-O-acetylated sialic acids drives IDV entry, we took advantage of a CASD1 knockout (KO) MDCK cell line and carried out feeding experiments using synthetic 9-O-acetyl sialic acids in combination with the single-round and multi-round IDV infection assays. The data from our studies show that (i) CASD1 KO cells are resistant to IDV infection and lack of IDV binding to the cell surface is responsible for the failure of IDV replication; (ii) feeding CASD1 KO cells with Neu5,9Ac2 or Neu5Gc9Ac resulted in a dose-dependent rescue of IDV infectivity; and (iii) diverse IDVs replicated robustly in CASD1 KO cells fed with either Neu5,9Ac2 or Neu5Gc9Ac at a level similar to that in wild-type cells with a functional CASD1. These data demonstrate that IDV can utilize Neu5,9Ac2- or non-human Neu5Gc9Ac-containing glycan receptor for infection. Our findings provide evidence that IDV has acquired the ability to infect and transmit among agricultural animals that are enriched in Neu5Gc9Ac, in addition to posing a zoonotic risk to humans expressing only Neu5,9Ac2.IMPORTANCEInfluenza D virus (IDV) has emerged as a multiple-species-infecting pathogen with bovines as a primary reservoir. Little is known about the functional receptor that drives IDV entry and promotes its cross-species spillover potential among different hosts. Here, we demonstrated that IDV binds exclusively to 9-O-acetylated N-acetylneuraminic acid (Neu5,9Ac2) and non-human 9-O-acetylated N-glycolylneuraminic acid (Neu5Gc9Ac) and utilizes both for entry and infection. This ability in effective engagement of both 9-O-acetylated sialic acids as functional receptors for infection provides an evolutionary advantage to IDV for expanding its host range. This finding also indicates that IDV has the potential to emerge in humans because Neu5,9Ac2 is ubiquitously expressed in human tissues, including lung. Thus, results of our study highlight a need for continued surveillance of IDV in humans, as well as for further investigation of its biology and cross-species transmission mechanism.


Asunto(s)
Deltainfluenzavirus , Ácidos Neuramínicos , Receptores Virales , Animales , Bovinos , Membrana Celular/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Ácidos Neuramínicos/metabolismo , Orthomyxoviridae/metabolismo , Receptores Virales/metabolismo , Ácidos Siálicos/metabolismo
7.
Cerebrovasc Dis ; : 1-10, 2024 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-38583429

RESUMEN

INTRODUCTION: Female participation is lower than males in both acute stroke and stroke rehabilitation trials. However, less is known about how female participation differs across countries and regions. This study aimed to assess the percentage of female participants in randomized controlled trials (RCTs) of post-stroke rehabilitation of upper extremity (UE) motor disorders in low-middle-income (LMICs) and high-income countries (HICs) as well as different high-income world regions. METHODS: CINAHL, Embase, PubMed, Scopus, and Web of Science were searched from 1960 to April 1, 2021. Studies were eligible for inclusion if they (1) were RCTs or crossovers published in English; (2) ≥50% of participants were diagnosed with stroke; 3) included adults ≥18 years old; and (4) applied an intervention to the hemiparetic UE as the primary objective of the study. Countries were divided into HICs and LMICs based on their growth national incomes. The HICs were further divided into the three high-income regions of North America, Europe, and Asia and Oceania. Data analysis was performed using SPSS and RStudio v.4.3.1. RESULTS: A total of 1,276 RCTs met inclusion criteria. Of them, 298 RCTs were in LMICs and 978 were in HICs. The percentage of female participants was significantly higher in HICs (39.5%) than LMICs (36.9%). Comparing high-income regions, there was a significant difference in the overall female percentages in favor of RCTs in Europe compared to LMICs but not North America or Asia and Oceania. There was no significant change in the percentage of female participants in all countries and regions over the last 2 decades, with no differences in trends between the groups. CONCLUSIONS: Sufficient female representation in clinical trials is required for the generalizability of results. Despite differences in overall percentage of female participation between countries and regions, females have been underrepresented in both HICs and LMICs with no considerable change over 2 decades.

9.
Respiration ; 103(5): 280-288, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38471496

RESUMEN

INTRODUCTION: Lung cancer remains the leading cause of cancer death worldwide. Subsolid nodules (SSN), including ground-glass nodules (GGNs) and part-solid nodules (PSNs), are slow-growing but have a higher risk for malignancy. Therefore, timely diagnosis is imperative. Shape-sensing robotic-assisted bronchoscopy (ssRAB) has emerged as reliable diagnostic procedure, but data on SSN and how ssRAB compares to other diagnostic interventions such as CT-guided transthoracic biopsy (CTTB) are scarce. In this study, we compared diagnostic yield of ssRAB versus CTTB for evaluating SSN. METHODS: A retrospective study of consecutive patients who underwent either ssRAB or CTTB for evaluating GGN and PSN with a solid component less than 6 mm from February 2020 to April 2023 at Mayo Clinic Florida and Rochester. Clinicodemographic information, nodule characteristics, diagnostic yield, and complications were compared between ssRAB and CTTB. RESULTS: A total of 66 nodules from 65 patients were evaluated: 37 PSN and 29 GGN. Median size of PSN solid component was 5 mm (IQR: 4.5, 6). Patients were divided into two groups: 27 in the ssRAB group and 38 in the CTTB group. Diagnostic yield was 85.7% for ssRAB and 89.5% for CTTB (p = 0.646). Sensitivity for malignancy was similar between ssRAB and CTTB (86.4% vs. 88.5%; p = 0.828), with no statistical difference. Complications were more frequent in CTTB with no significant difference (8 vs. 2; p = 0.135). CONCLUSION: Diagnostic yield for SSN was similarly high for ssRAB and CTTB, with ssRAB presenting less complications and allowing mediastinal staging within the same procedure.


Asunto(s)
Broncoscopía , Biopsia Guiada por Imagen , Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Procedimientos Quirúrgicos Robotizados , Tomografía Computarizada por Rayos X , Humanos , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Broncoscopía/métodos , Anciano , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagen , Biopsia Guiada por Imagen/métodos , Procedimientos Quirúrgicos Robotizados/métodos , Nódulos Pulmonares Múltiples/patología , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Nódulos Pulmonares Múltiples/diagnóstico , Nódulo Pulmonar Solitario/patología , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/diagnóstico
10.
Rapid Commun Mass Spectrom ; 37(5): e9439, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36415963

RESUMEN

RATIONALE: Isomeric separation of prostanoids is often a challenge and requires chromatography and time-consuming sample preparation. Multiple prostanoid isomers have distinct in vivo functions crucial for understanding the inflammation process, including prostaglandins E2 (PGE2 ) and D2 (PGD2 ). High-resolution ion mobility spectrometry (IMS) based on linear ion transport in low-to-moderate electric fields and nonlinear ion transport in strong electric fields emerges as a broad approach for rapid separations prior to mass spectrometry. METHODS: Derivatization with Girard's reagent T (GT) was used to overcome inefficient ionization of prostanoids in negative ionization mode due to poor deprotonation of the carboxylic acid group. Three high-resolution IMS techniques, namely linear cyclic IMS, linear trapped IMS, and nonlinear high-field asymmetric waveform IMS, were compared for the isomeric separation and endogenous detection of prostanoids present in intestinal tissue. RESULTS: Direct infusion of GT-derivatized prostanoids proved to increase the ionization efficiency in positive ionization mode by a factor of >10, which enabled detection of these molecules in endogenous concentration levels. The high-resolution IMS comparison revealed its potential for rapid isomeric analysis of biologically relevant prostanoids. Strengths and weaknesses of both linear and nonlinear IMS are discussed. Endogenous prostanoid detection in intestinal tissue extracts demonstrated the applicability of our approach in biomedical research. CONCLUSIONS: The applied derivatization strategy offers high sensitivity and improved stereoisomeric separation for screening of complex biological systems. The high-resolution IMS comparison indicated that the best sensitivity and resolution are achieved by linear and nonlinear IMS, respectively.


Asunto(s)
Espectrometría de Movilidad Iónica , Prostaglandinas , Espectrometría de Movilidad Iónica/métodos , Espectrometría de Masas/métodos , Betaína/química
11.
Respirology ; 28(1): 66-73, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36104312

RESUMEN

BACKGROUND AND OBJECTIVE: Currently, computed tomography-guided transthoracic biopsy (CTTB) is the most accurate diagnostic approach for pulmonary nodules suspected of malignancy. Traditional bronchoscopy has shown suboptimal diagnostic sensitivity, but the emergence of robotic-assisted bronchoscopy (RAB) has the potential to improve diagnostic accuracy, maximize diagnostic yield and complete mediastinal and hilar staging in a single procedure. We aim to assess the efficacy and diagnostic performance of RAB compared to CTTB for diagnosing pulmonary nodules suspected of lung cancer. METHODS: A multicenter retrospective review of consecutive patients who underwent RAB and CTTB for evaluating pulmonary nodules from January 2019 to March 2021 at Mayo Clinic Florida and Mayo Clinic Rochester, United States. Clinical and demographic information, nodule characteristics, outcomes and complications were compared between RAB and CTTB. RESULTS: A total of 225 patients were included: 113 in the RAB group and 112 in the CTTB group. Overall diagnostic yield was 87.6% for RAB and 88.4% for CTTB. For malignant disease, RAB had a sensitivity of 82.1% and a specificity of 100%, CTTB had a sensitivity of 88.5% and a specificity of 100%. Complication rate was significantly higher for CTTB compared to RAB (17% vs. 4.4%; p = 0.002). CONCLUSION: RAB, when available, can be as accurate as CTTB for sampling pulmonary nodules with similar or reduced complications and should be considered as a means for nodule biopsy, particularly when mediastinal staging is also clinically warranted.


Asunto(s)
Neoplasias Pulmonares , Nódulos Pulmonares Múltiples , Procedimientos Quirúrgicos Robotizados , Nódulo Pulmonar Solitario , Humanos , Broncoscopía/métodos , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Nódulos Pulmonares Múltiples/patología , Biopsia Guiada por Imagen/métodos , Tomografía Computarizada por Rayos X/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Estudios Retrospectivos , Nódulo Pulmonar Solitario/diagnóstico por imagen , Nódulo Pulmonar Solitario/patología , Pulmón/diagnóstico por imagen , Pulmón/patología
12.
J Ultrasound Med ; 42(4): 777-790, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36106721

RESUMEN

Medical simulation training can be used to improve clinician performance, teach communication and professionalism skills, and enhance team training. Radiology residents can benefit from simulation training in diagnostic ultrasound, procedural ultrasound, and communication skills prior to direct patient care experiences. This paper details a weeklong ultrasound simulation training curriculum for radiology residents during the PGY-1 clinical internship. The organization of established teaching methods into a dedicated course early in radiology residency training with the benefit of a multi-disciplinary approach makes this method unique. This framework can be adapted to fit learners at different skill levels or with specific procedural needs.


Asunto(s)
Internado y Residencia , Radiología , Entrenamiento Simulado , Humanos , Curriculum , Radiología/educación , Ultrasonografía , Competencia Clínica
13.
J Lipid Res ; 63(6): 100223, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35537528

RESUMEN

The cellular energy and biomass demands of cancer drive a complex dynamic between uptake of extracellular FAs and their de novo synthesis. Given that oxidation of de novo synthesized FAs for energy would result in net-energy loss, there is an implication that FAs from these two sources must have distinct metabolic fates; however, hitherto, all FAs have been considered part of a common pool. To probe potential metabolic partitioning of cellular FAs, cancer cells were supplemented with stable isotope-labeled FAs. Structural analysis of the resulting glycerophospholipids revealed that labeled FAs from uptake were largely incorporated to canonical (sn-) positions on the glycerol backbone. Surprisingly, labeled FA uptake also disrupted canonical isomer patterns of the unlabeled lipidome and induced repartitioning of n-3 and n-6 PUFAs into glycerophospholipid classes. These structural changes support the existence of differences in the metabolic fates of FAs derived from uptake or de novo sources and demonstrate unique signaling and remodeling behaviors usually hidden from conventional lipidomics.


Asunto(s)
Ácidos Grasos , Neoplasias , Ácidos Grasos/metabolismo , Glicerofosfolípidos/química , Metabolismo de los Lípidos , Transducción de Señal
14.
Emerg Infect Dis ; 28(10): 2035-2042, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36084650

RESUMEN

Reducing zoonotic influenza A virus (IAV) risk in the United States necessitates mitigation of IAV in exhibition swine. We evaluated the effectiveness of shortening swine exhibitions to <72 hours to reduce IAV risk. We longitudinally sampled every pig daily for the full duration of 16 county fairs during 2014-2015 (39,768 nasal wipes from 6,768 pigs). In addition, we estimated IAV prevalence at 195 fairs during 2018-2019 to test the hypothesis that <72-hour swine exhibitions would have lower IAV prevalence. In both studies, we found that shortening duration drastically reduces IAV prevalence in exhibition swine at county fairs. Reduction of viral load in the barn within a county fair is critical to reduce the risk for interspecies IAV transmission and pandemic potential. Therefore, we encourage fair organizers to shorten swine shows to protect the health of both animals and humans.


Asunto(s)
Virus de la Influenza A , Gripe Humana , Infecciones por Orthomyxoviridae , Enfermedades de los Porcinos , Animales , Humanos , Virus de la Influenza A/genética , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Nariz , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/prevención & control , Infecciones por Orthomyxoviridae/veterinaria , Prevalencia , Porcinos , Enfermedades de los Porcinos/epidemiología , Enfermedades de los Porcinos/prevención & control , Estados Unidos
15.
EMBO J ; 37(19)2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30177573

RESUMEN

Newly synthesised histones are thought to dimerise in the cytosol and undergo nuclear import in complex with histone chaperones. Here, we provide evidence that human H3.1 and H4 are imported into the nucleus as monomers. Using a tether-and-release system to study the import dynamics of newly synthesised histones, we find that cytosolic H3.1 and H4 can be maintained as stable monomeric units. Cytosolically tethered histones are bound to importin-alpha proteins (predominantly IPO4), but not to histone-specific chaperones NASP, ASF1a, RbAp46 (RBBP7) or HAT1, which reside in the nucleus in interphase cells. Release of monomeric histones from their cytosolic tether results in rapid nuclear translocation, IPO4 dissociation and incorporation into chromatin at sites of replication. Quantitative analysis of histones bound to individual chaperones reveals an excess of H3 specifically associated with sNASP, suggesting that NASP maintains a soluble, monomeric pool of H3 within the nucleus and may act as a nuclear receptor for newly imported histone. In summary, we propose that histones H3 and H4 are rapidly imported as monomeric units, forming heterodimers in the nucleus rather than the cytosol.


Asunto(s)
Núcleo Celular/metabolismo , Histonas/metabolismo , Interfase/fisiología , Chaperonas Moleculares/metabolismo , Transporte Activo de Núcleo Celular/fisiología , Núcleo Celular/genética , Células HeLa , Histonas/genética , Humanos , Chaperonas Moleculares/genética
16.
BMC Gastroenterol ; 22(1): 336, 2022 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-35818022

RESUMEN

BACKGROUND: Incidentalomas, defined as incidental findings on imaging, are a growing concern. Our aim was to determine the impact and outcomes of extrahepatic incidentalomas on liver transplantation. METHODS: Patients at a large liver transplant center, who had an initial MRI for hepatocellular carcinoma screening between January 2004 and March 2020 were identified. Clinical data were collected retrospectively. Survival analysis, utilizing Kaplan Meier estimates and Cox proportional hazards regression analysis, was utilized to determine factors associated with liver transplantation. RESULTS: 720 patients were included. NASH (24.9%), HCV (22.1%) and alcohol (20.6%) were the most common causes of cirrhosis. 79.7% of patients had an extrahepatic incidentaloma. Older age and having received a liver transplant by the end of the study were associated with an incidentaloma. MELD was not associated with the presence of an incidentaloma. On univariate Cox proportional hazards regression, male sex, history of moderate alcohol use, smoking history, MELD, and incidentalomas were predictors of liver transplantation. On multivariate analysis, only MELD and the presence of an incidentaloma were found to be significant. Discovery of an incidentaloma was associated with a 30% increase in the risk of liver transplantation. Median time to transplantation did not differ based on the presence on an incidentaloma. Patients with cirrhosis from alcohol or HCV had a significantly shorter median time to transplantation than those with NASH. Renal and pancreatic lesions comprised 91% of all incidentalomas. CONCLUSIONS: In this single-center retrospective study, extrahepatic incidentalomas were common in patients with cirrhosis. The finding of an incidentaloma was associated with a higher risk of liver transplantation despite a similar median time to transplantation if no incidentaloma was discovered.


Asunto(s)
Hepatitis C , Neoplasias Hepáticas , Trasplante de Hígado , Enfermedad del Hígado Graso no Alcohólico , Humanos , Cirrosis Hepática/complicaciones , Cirrosis Hepática/epidemiología , Cirrosis Hepática/cirugía , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/cirugía , Masculino , Estudios Retrospectivos
17.
Radiographics ; 42(4): 1043-1061, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35687520

RESUMEN

Focal nodular hyperplasia (FNH) is a benign lesion occurring in a background of normal liver. FNH is seen most commonly in young women and can often be accurately diagnosed at imaging, including CT, MRI, or contrast-enhanced US. In the normal liver, FNH frequently must be differentiated from hepatocellular adenoma, which although benign, is managed differently because of the risks of hemorrhage and malignant transformation. When lesions that are histologically identical to FNH occur in a background of abnormal liver, they are termed FNH-like lesions. These lesions can be a source of diagnostic confusion and must be differentiated from malignancies. Radiologists' familiarity with the imaging appearance of FNH-like lesions and knowledge of the conditions that predispose a patient to their formation are critical to minimizing the risks of unnecessary intervention for these lesions, which are rarely symptomatic and carry no risk for malignant transformation. FNH is thought to form secondary to an underlying vascular disturbance, a theory supported by the predilection for formation of FNH-like lesions in patients with a variety of hepatic vascular abnormalities. These include abnormalities of hepatic outflow such as Budd-Chiari syndrome, abnormalities of hepatic inflow such as congenital absence of the portal vein, and hepatic microvascular disturbances, such as those that occur after exposure to certain chemotherapeutic agents. Familiarity with the imaging appearances of these varied conditions and knowledge of their association with formation of FNH-like lesions allow radiologists to identify with confidence these benign lesions that require no intervention. Online supplemental material is available for this article. ©RSNA, 2022.


Asunto(s)
Hiperplasia Nodular Focal , Neoplasias Hepáticas , Diagnóstico Diferencial , Femenino , Hiperplasia Nodular Focal/complicaciones , Hiperplasia Nodular Focal/diagnóstico por imagen , Humanos , Hiperplasia/complicaciones , Hiperplasia/patología , Hígado/irrigación sanguínea , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Vena Porta
18.
Radiographics ; 42(3): 919-928, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35333633

RESUMEN

Kaizen process improvement is an element of lean production that is an approach to creating continuous improvement. Kaizen is based on the idea that small ongoing positive changes in workflow and elimination of waste can yield major improvements over time. A focused Kaizen event, or rapid process improvement event, can lead to sustainable process improvement in health care settings that are resistant to change. This approach has been proven to be successful in health care. These events are led by a trained facilitator and coach who provides appropriate team education and engagement. To ensure success, the team must embrace the Kaizen culture, which emphasizes the development of a "learning organization" that is focused on relentless pursuit of perfection. The culture empowers all staff to improve the work they perform, with an emphasis on the process and not the individual. Respect for individual people is key in Kaizen. In radiology, this method has been successful in empowering frontline staff to improve their individual workflows. A 5-day Kaizen event has been successful in increasing on-time starts, decreasing lead time, increasing patient and staff satisfaction, and ensuring sustainability. Sustainable success can occur when the team stays true to lean principles, engages leaders, and empowers team members with the use of timely data to drive decision making. Online supplemental material is available for this article. ©RSNA, 2022.


Asunto(s)
Mejoramiento de la Calidad , Radiología , Humanos
20.
Nano Lett ; 21(14): 5991-5997, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34264685

RESUMEN

Recent nanoscale ballistic tests have shown the applicability of nanomaterials for ballistic protection but have raised questions regarding the nanoscale structure-property relationships that contribute to the ballistic response. Herein, we report on multimillion-atom reactive molecular dynamics simulations of the supersonic impact, penetration, and failure of polyethylene (PE) and polystyrene (PS) ultrathin films. The simulated specific penetration energy (Ep*) versus impact velocity predicts to within 15% the experimentally determined Ep* for PS. For impact velocities less than 1 km s-1, a crazing/petalling failure mode is observed due to chain disentanglement, transitioning to fragmentation coupled with large amounts of adiabatic heating at velocities greater than 1 km s-1. Interestingly, the high entanglement density of PE provides enhanced penetration resistance at low velocities, whereas increased adiabatic heating in PS promotes greater penetration resistance at elevated velocities. By understanding nanoscale mechanisms of energy absorption, nanomaterials can be designed to provide superior penetration resistance.


Asunto(s)
Simulación de Dinámica Molecular , Polímeros , Poliestirenos
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