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1.
Pediatr Neurol ; 154: 44-50, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38518503

RESUMO

BACKGROUND: Infants with hypoxic ischemic encephalopathy (HIE) may have underlying conditions predisposing them to hypoxic-ischemic injury during labor and delivery. It is unclear how genetic and congenital anomalies impact outcomes of HIE. METHODS: Infants with HIE enrolled in a phase III trial underwent genetic testing when clinically indicated. Infants with known genetic or congenital anomalies were excluded. The primary outcome, i.e., death or neurodevelopmental impairment (NDI), was determined at age two years by a standardized neurological examination, Bayley Scales of Infant Development, Third Edition (BSID-III), and the Gross Motor Function Classification Scales. Secondary outcomes included cerebral palsy and BSID-III motor, cognitive, and language scores at age two years. RESULTS: Of 500 infants with HIE, 24 (5%, 95% confidence interval 3% to 7%) were diagnosed with a genetic (n = 15) or congenital (n = 14) anomaly. Infants with and without genetic or congenital anomalies had similar rates of severe encephalopathy and findings on brain magnetic resonance imaging. However, infants with genetic or congenital anomalies were more likely to have death or NDI (75% vs 50%, P = 0.02). Among survivors, those with a genetic or congenital anomaly were more likely to be diagnosed with cerebral palsy (32% vs 13%, P = 0.02), and had lower BSID-III scores in all three domains than HIE survivors without such anomalies. CONCLUSIONS: Among infants with HIE, 5% were diagnosed with a genetic or congenital anomaly. Despite similar clinical markers of HIE severity, infants with HIE and a genetic or congenital anomaly had worse neurodevelopmental outcomes than infants with HIE alone.


Assuntos
Paralisia Cerebral , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Lactente , Criança , Humanos , Pré-Escolar , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Hipóxia-Isquemia Encefálica/genética , Paralisia Cerebral/complicações , Imageamento por Ressonância Magnética/métodos , Encéfalo , Hipotermia Induzida/métodos
3.
PLoS One ; 19(1): e0280366, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38241310

RESUMO

The Northern California Current is a highly productive marine upwelling ecosystem that is economically and ecologically important. It is home to both commercially harvested species and those that are federally listed under the U.S. Endangered Species Act. Recently, there has been a global shift from single-species fisheries management to ecosystem-based fisheries management, which acknowledges that more complex dynamics can reverberate through a food web. Here, we have integrated new research into an end-to-end ecosystem model (i.e., physics to fisheries) using data from long-term ocean surveys, phytoplankton satellite imagery paired with a vertically generalized production model, a recently assembled diet database, fishery catch information, species distribution models, and existing literature. This spatially-explicit model includes 90 living and detrital functional groups ranging from phytoplankton, krill, and forage fish to salmon, seabirds, and marine mammals, and nine fisheries that occur off the coast of Washington, Oregon, and Northern California. This model was updated from previous regional models to account for more recent changes in the Northern California Current (e.g., increases in market squid and some gelatinous zooplankton such as pyrosomes and salps), to expand the previous domain to increase the spatial resolution, to include data from previously unincorporated surveys, and to add improved characterization of endangered species, such as Chinook salmon (Oncorhynchus tshawytscha) and southern resident killer whales (Orcinus orca). Our model is mass-balanced, ecologically plausible, without extinctions, and stable over 150-year simulations. Ammonium and nitrate availability, total primary production rates, and model-derived phytoplankton time series are within realistic ranges. As we move towards holistic ecosystem-based fisheries management, we must continue to openly and collaboratively integrate our disparate datasets and collective knowledge to solve the intricate problems we face. As a tool for future research, we provide the data and code to use our ecosystem model.


Assuntos
Ecossistema , Cadeia Alimentar , Animais , Salmão , Peixes , Espécies em Perigo de Extinção , Fitoplâncton , California , Pesqueiros , Mamíferos
4.
Genome Biol ; 24(1): 284, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066546

RESUMO

BACKGROUND: Point mutations in histone variant H3.3 (H3.3K27M, H3.3G34R) and the H3.3-specific ATRX/DAXX chaperone complex are frequent events in pediatric gliomas. These H3.3 point mutations affect many chromatin modifications but the exact oncogenic mechanisms are currently unclear. Histone H3.3 is known to localize to nuclear compartments known as promyelocytic leukemia (PML) nuclear bodies, which are frequently mutated and confirmed as oncogenic drivers in acute promyelocytic leukemia. RESULTS: We find that the pediatric glioma-associated H3.3 point mutations disrupt the formation of PML nuclear bodies and this prevents differentiation down glial lineages. Similar to leukemias driven by PML mutations, H3.3-mutated glioma cells are sensitive to drugs that target PML bodies. We also find that point mutations in IDH1/2-which are common events in adult gliomas and myeloid leukemias-also disrupt the formation of PML bodies. CONCLUSIONS: We identify PML as a contributor to oncogenesis in a subset of gliomas and show that targeting PML bodies is effective in treating these H3.3-mutated pediatric gliomas.


Assuntos
Neoplasias Encefálicas , Glioma , Histonas , Adulto , Criança , Humanos , Neoplasias Encefálicas/genética , Glioma/genética , Histonas/genética , Mutação , Corpos Nucleares da Leucemia Promielocítica
5.
ACS Nano ; 17(19): 19109-19120, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37748102

RESUMO

Semiconductor nanocrystals are promising optoelectronic materials. Understanding their anisotropic photoluminescence is fundamental for developing quantum-dot-based devices such as light-emitting diodes, solar cells, and polarized single-photon sources. In this study, we experimentally and theoretically investigate the photoluminescence anisotropy of CdSe semiconductor nanocrystals with various shapes, including plates, rods, and spheres, with either wurtzite or zincblende structures. We use defocused wide-field microscopy to visualize the emission dipole orientation and find that spheres, rods, and plates exhibit the optical properties of 2D, 1D, and 2D emission dipoles, respectively. We rationalize the seemingly counterintuitive observation that despite having similar aspect ratios (width/length), rods and long nanoplatelets exhibit different defocused emission patterns by considering valence band structures calculated using multiband effective mass theory and the dielectric effect. The principles are extended to provide general relationships that can be used to tune the emission dipole orientation for different materials, crystalline structures, and shapes.

6.
ACS Chem Biol ; 18(8): 1863-1871, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37440171

RESUMO

"Reagentless" immunosensors are emerging to address the challenge of practical and sensitive detection of important biomarkers in real biological samples without the need for multistep assays and user intervention, with applications ranging from research tools to point-of-care diagnostics. Selective target binding to an affinity reagent is detected and reported in one step without the need for washing or additional reporters. In this study, we used a structure-guided approach to identify a mutation site in an antibody fragment for the polarity-dependent fluorophore, Anap, such that upon binding of the protein target cardiac troponin I, the Anap-labeled antibody would produce a detectable and dose-dependent shift in emission wavelength. We observed a significant emission wavelength shift of the Anap-labeled anti-cTnI mutant, with a blue shift of up to 37 nm, upon binding to the cTnI protein. Key differences in the resulting emission spectra between target peptides in comparison to whole proteins were also found; however, the affinity and binding characteristics remained unaffected when compared to the wild-type antibody. We also highlighted the potential flexibility of the approach by incorporating a near-infrared dye, IRDye800CW, into the same mutation site, which also resulted in a dose-dependent wavelength shift upon target incubation. These reagents can be used in experiments and devices to create simpler and more efficient biosensors across a range of research, medical laboratory, and point-of-care platforms.


Assuntos
Técnicas Biossensoriais , Técnicas Biossensoriais/métodos , Imunoensaio , Anticorpos/química , Peptídeos , Fragmentos de Imunoglobulinas , Troponina I/genética
7.
Surg Laparosc Endosc Percutan Tech ; 33(5): 505-510, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37523506

RESUMO

BACKGROUND: As laparoscopic bariatric surgical techniques have matured, the incidence of complications has decreased over time. Surgical stapling devices are commonly used for resection and anastomosis of gastric tissue during bariatric surgery. The purpose of this study is to assess and compare complication rates and clinical outcomes between patient cohorts using 2 different approved stapling devices. MATERIALS AND METHODS: Clinical outcomes were retrospectively compared for patients undergoing bariatric surgery between April 2019 and December 2020 using laparoscopic surgical stapling device A (LSSD-A) against outcomes between January 2017 and September 2018 using laparoscopic surgical stapling device B (LSSD-B). Tradenames for LSSD-A and LSSD-B were AEON Endostapler and Endo GIA with Tri-Staple Technology, respectively. RESULTS: In all, 814 patients underwent laparoscopic bariatric operation using LSSD-A and 1034 using LSSD-B. Laparoscopic surgery included sleeve gastrectomy (n=1359, 73.5%), Roux-en-Y gastric bypass (RYGB) (n=425, 23.0%), and single anastomosis duodenoileostomy with gastric sleeve (n=64, 3.5%). Stapler-related complications were evenly distributed over the 20.9-month LSSD-B study period. No stapler-related complications were seen in the last 13 months of the LSSD-A study period, during which time 428 (52.5%) laparoscopic bariatric operations were performed. One staple line leak was observed, occurring in the LSSD-B group. Patients undergoing laparoscopic RYGB with LSSD-A had fewer overall complications, fewer transfusions, and fewer reoperations for staple line bleeding. CONCLUSIONS: Both LSSD-A and LSSD-B were safe and effective in the performance of laparoscopic bariatric operations with low complication rates and comparable clinical performance in sleeve gastrectomy and single anastomosis duodenoileostomy with gastric sleeve. Statistically significant differences in complication rates were observed in RYGB favoring LSSD-A.

8.
ACS Bio Med Chem Au ; 3(3): 261-269, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37363082

RESUMO

Standard optical imaging is diffraction-limited and lacks the resolving power to visualize many of the organelles and proteins found within the cell. The advent of super-resolution techniques overcame this barrier, enabling observation of subcellular structures down to tens of nanometers in size; however these techniques require or are typically applied to fixed samples. This raises the question of how well a fixed-cell image represents the system prior to fixation. Here we present the addition of live-cell Super-Resolution Optical Fluctuation Imaging (SOFI) to a previously reported correlative process using Single Molecule Localization Microscopy (SMLM) and Atomic Force Microscopy (AFM). SOFI was used with fluorescent proteins and low laser power to observe cellular ultrastructure in live COS-7 cells. SOFI-SMLM-AFM of microtubules showed minimal changes to the microtubule network in the 20 min between live-cell SOFI and fixation. Microtubule diameters were also analyzed through all microscopies; SOFI found diameters of 249 ± 68 nm and SMLM was 71 ± 33 nm. AFM height measurements found microtubules to protrude 26 ± 13 nm above the surrounding cellular material. The correlation of SMLM and AFM was extended to two-color SMLM to image both microtubules and actin. Two target SOFI was performed with various fluorescent protein combinations. rsGreen1-rsKAME, rsGreen1-Dronpa, and ffDronpaF-rsKAME fluorescent protein combinations were determined to be suitable for two target SOFI imaging. This correlative application of super-resolution live-cell and fixed-cell imaging revealed minimal artifacts created for the imaged target structures through the sample preparation procedure and emphasizes the power of correlative microscopy.

9.
Semin Pediatr Surg ; 32(3): 151308, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37295297

RESUMO

Antibiotic therapy remains a cornerstone of treatment of both medical and surgical presentations of necrotizing enterocolitis (NEC). However, guidelines regarding the administration of antibiotics for the treatment of NEC are lacking and practices vary amongst clinicians. Although the pathogenesis of NEC is unknown, there is consensus that the infant gastrointestinal microbiome contributes to the disease. The presumed connection between dysbiosis and NEC has prompted some to study whether early prophylactic enteral antibiotics can prevent NEC. Yet others have taken an opposing approach, studying whether perinatal antibiotic exposure increases the risk of NEC by inducing a state of dysbiosis. This narrative review summarizes what is known about antibiotics and their association with the infant microbiome and NEC, current antibiotic prescribing practices for infants with medical and surgical NEC, as well as potential strategies to further optimize the use of antibiotics in this population of infants.


Assuntos
Enterocolite Necrosante , Doenças Fetais , Microbioma Gastrointestinal , Doenças do Recém-Nascido , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Enterocolite Necrosante/tratamento farmacológico , Enterocolite Necrosante/etiologia , Disbiose/complicações , Disbiose/tratamento farmacológico , Antibacterianos/uso terapêutico
10.
Nature ; 618(7967): 981-985, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37225998

RESUMO

Soils store more carbon than other terrestrial ecosystems1,2. How soil organic carbon (SOC) forms and persists remains uncertain1,3, which makes it challenging to understand how it will respond to climatic change3,4. It has been suggested that soil microorganisms play an important role in SOC formation, preservation and loss5-7. Although microorganisms affect the accumulation and loss of soil organic matter through many pathways4,6,8-11, microbial carbon use efficiency (CUE) is an integrative metric that can capture the balance of these processes12,13. Although CUE has the potential to act as a predictor of variation in SOC storage, the role of CUE in SOC persistence remains unresolved7,14,15. Here we examine the relationship between CUE and the preservation of SOC, and interactions with climate, vegetation and edaphic properties, using a combination of global-scale datasets, a microbial-process explicit model, data assimilation, deep learning and meta-analysis. We find that CUE is at least four times as important as other evaluated factors, such as carbon input, decomposition or vertical transport, in determining SOC storage and its spatial variation across the globe. In addition, CUE shows a positive correlation with SOC content. Our findings point to microbial CUE as a major determinant of global SOC storage. Understanding the microbial processes underlying CUE and their environmental dependence may help the prediction of SOC feedback to a changing climate.


Assuntos
Sequestro de Carbono , Carbono , Ecossistema , Microbiologia do Solo , Solo , Carbono/análise , Carbono/metabolismo , Mudança Climática , Plantas , Solo/química , Conjuntos de Dados como Assunto , Aprendizado Profundo
11.
Proc Natl Acad Sci U S A ; 120(14): e2217066120, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36989298

RESUMO

Viruses form extensive interfaces with host proteins to modulate the biology of the infected cell, frequently via multifunctional viral proteins. These proteins are conventionally considered as assemblies of independent functional modules, where the presence or absence of modules determines the overall composite phenotype. However, this model cannot account for functions observed in specific viral proteins. For example, rabies virus (RABV) P3 protein is a truncated form of the pathogenicity factor P protein, but displays a unique phenotype with functions not seen in longer isoforms, indicating that changes beyond the simple complement of functional modules define the functions of P3. Here, we report structural and cellular analyses of P3 derived from the pathogenic RABV strain Nishigahara (Nish) and an attenuated derivative strain (Ni-CE). We identify a network of intraprotomer interactions involving the globular C-terminal domain and intrinsically disordered regions (IDRs) of the N-terminal region that characterize the fully functional Nish P3 to fluctuate between open and closed states, whereas the defective Ni-CE P3 is predominantly open. This conformational difference appears to be due to the single mutation N226H in Ni-CE P3. We find that Nish P3, but not Ni-CE or N226H P3, undergoes liquid-liquid phase separation and this property correlates with the capacity of P3 to interact with different cellular membrane-less organelles, including those associated with immune evasion and pathogenesis. Our analyses propose that discrete functions of a critical multifunctional viral protein depend on the conformational arrangements of distant individual domains and IDRs, in addition to their independent functions.


Assuntos
Vírus da Raiva , Raiva , Humanos , Vírus da Raiva/genética , Proteínas Virais/genética , Proteínas Virais/metabolismo , Fatores de Virulência/metabolismo , Isoformas de Proteínas/metabolismo
12.
Int J Cardiol Heart Vasc ; 44: 101166, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36620203

RESUMO

Rationale and objectives: Determine in cardiac amyloid (CA) patients, whether cardiac CT derived extracellular volume (ECV) correlates with that obtained by MRI. Perform this correlation with single (SECT) versus dual energy (DECT) CT and evaluate whether a single sample volume ECV-measure was as reliable as a global (16 segment) assessment. Materials and methods: CA patients who had undergone a clinical cardiac MRI (CMR) were recruited prospectively. SECT and DECT cardiac scans were performed. Three ECG-triggered prospective SECT scans were acquired: non-contrast, arterial-phase contrast and 5-minute delayed images. A DECT scan was performed at 7 min. Post processing was used to determine ECV. Analyses of SECT or DECT global ECV versus CMR were performed using the Pearson correlation coefficient, Bland Altman analysis and Intraclass correlation coefficient (ICC). Similar analyses were performed to examine the performance of single-segment sampling by SECT or DECT versus CMR. Results: 25 patients were recruited, mean age was 80.0 ± 7.1 years, 80 % were male, 21 patients had transthyretin- CA, 4 had light chain- CA. Correlations were close with both SECT or DECT global ECV versus CMR (r = 0.79 and 0.88 respectively, p < 0.001 for both). Reliability of both SECT and DECT to assess global ECV in comparison to CMR was good: ICC for SECT was 0.88 (95 % CI 0.73-0.95) and 0.93 (95 % CI 0.82-0.97) for DECT. For single volume sampling techniques: correlations were close with both SECT or DECT versus CMR (r = 0.60 and 0.72 respectively, p < 0.01 for both) There was no difference in ICC for SECT (0.74, 95 %CI 0.41-0.88) versus DECT (0.84, 95 % CI 0.63-0.93). Wider confidence intervals were noted for ICC with single versus global CT derived ECV assessment. Mean effective radiation dose was for SECT was 5.49 ± 8.04 mSv and 6.90 ± 3.01 mSv for DECT dual energy CT (p = 0.75). Conclusions: Global ECV values derived by both DECT or SECT correlated with those obtained by CMR and demonstrated good reliability by ICC in a population of CA patients. DECT and SECT single sampling derived ECV values also demonstrated close correlation and good reliability but the ICCs for single sampling had wider confidence intervals than global ECV assessment.

13.
Psychiatry ; 86(1): 29-41, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36265001

RESUMO

Background: Soldiers are resilient to just war events, such as killing enemy combatants and life-threatening experiences, but these same soldiers appear to struggle with unjust war events, such as killing a noncombatant or being unable to help civilian women and children in need. This study is the first to examine how just and unjust war experiences are associated with clinical health service outcomes. Methods: Two samples of soldiers in different stages of readjustment from deployment were drawn from a longitudinal, survey-based study of a US Army brigade. Measures included items related to combat events, mental health utilization, perceived mental health need, PTSD, depression, and functional impairment. Results: After controlling for other kinds of combat events, just war events (i.e., life-threatening events and killing enemy combatants) predicted outcomes in soldiers who are less than three months post-deployment, but only predicted 2 of 26 outcomes in soldiers one year post deployment. In contrast, unjust war events were found to be robust predictors of short-term and long-term outcomes related to mental health need and utilization, even after controlling for exposure to other combat events. Conclusions: The results extend previous longitudinal research that suggests that exposure to unjust war events carry a heavier long-term mental health burden than other types of events. Additionally, Soldiers exposed to unjust war events had an unmet need for care one year post deployment that was not directly tied to PTSD or depression. The results question the emphasis on life-threat within mental health pathogenesis models.


Assuntos
Militares , Transtornos de Estresse Pós-Traumáticos , Criança , Humanos , Feminino , Saúde Mental , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Militares/psicologia , Inquéritos e Questionários , Estudos Longitudinais
14.
IEEE Robot Autom Lett ; 8(8): 5055-5060, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38283263

RESUMO

The clinical efficacy of robotic rehabilitation interventions hinges on appropriate neuromuscular recruitment from the patient. The first purpose of this study was to evaluate the use of supervised machine learning techniques to predict neuromuscular recruitment of the ankle plantar flexors during walking with ankle exoskeleton resistance in individuals with cerebral palsy (CP). The second goal of this study was to utilize the predictive models of plantar flexor recruitment in the design of a personalized biofeedback framework intended to improve (i.e., increase) user engagement when walking with resistance. First, we developed and trained multilayer perceptrons (MLPs), a type of artificial neural network (ANN), utilizing features extracted exclusively from the exoskeleton's onboard sensors, and demonstrated 85-87% accuracy, on average, in predicting muscle recruitment from electromyography measurements. Next, our participants completed a gait training session while receiving audio-visual biofeedback of their personalized real-time planar flexor recruitment predictions from the online MLP. We found that adding biofeedback to resistance elevated plantar flexor recruitment by 24 16% compared to resistance alone. This study highlights the potential for online machine learning frameworks to improve the effectiveness and delivery of robotic rehabilitation systems in clinical populations.

15.
J Virol ; 96(20): e0139622, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36222519

RESUMO

Viral hijacking of microtubule (MT)-dependent transport is well understood, but several viruses also express discrete MT-associated proteins (vMAPs), potentially to modulate MT-dependent processes in the host cell. Specific roles for vMAP-MT interactions include subversion of antiviral responses by P3, an isoform of the P protein of rabies virus (RABV; genus Lyssavirus), which mediates MT-dependent antagonism of interferon (IFN)-dependent signal transducers and activators of transcription 1 (STAT1) signaling. P3 also undergoes nucleocytoplasmic trafficking and inhibits STAT1-DNA binding, indicative of intranuclear roles in a multipronged antagonistic strategy. MT association/STAT1 antagonist functions of P3 correlate with pathogenesis, indicating potential as therapeutic targets. However, key questions remain, including whether other P protein isoforms interact with MTs, the relationship of these interactions with pathogenesis, and the extent of conservation of P3-MT interactions between diverse pathogenic lyssaviruses. Using super-resolution microscopy, live-cell imaging, and immune signaling analyses, we find that multiple P protein isoforms associate with MTs and that association correlates with pathogenesis. Furthermore, P3 proteins from different lyssaviruses exhibit variation in intracellular localization phenotypes that are associated with STAT1 antagonist function, whereby P3-MT association is conserved among lyssaviruses of phylogroup I but not phylogroup II, while nucleocytoplasmic localization varies between P3 proteins of the same phylogroup within both phylogroup I and II. Nevertheless, the divergent P3 proteins retain significant IFN antagonist function, indicative of adaptation to favor different inhibitory mechanisms, with MT interaction important to phylogroup I viruses. IMPORTANCE Lyssaviruses, including rabies virus, cause rabies, a progressive encephalomyelitis that is almost invariably fatal. There are no effective antivirals for symptomatic infection, and effective application of current vaccines is limited in areas of endemicity, such that rabies causes ~59,000 deaths per year. Viral subversion of host cell functions, including antiviral immunity, is critical to disease, and isoforms of the lyssavirus P protein are central to the virus-host interface underpinning immune evasion. Here, we show that specific cellular interactions of P protein isoforms involved in immune evasion vary significantly between different lyssaviruses, indicative of distinct strategies to evade immune responses. These findings highlight the diversity of the virus-host interface, an important consideration in the development of pan-lyssavirus therapeutic approaches.


Assuntos
Lyssavirus , Vacina Antirrábica , Vírus da Raiva , Raiva , Humanos , Lyssavirus/genética , Interferons/metabolismo , Vírus da Raiva/genética , Antivirais/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , DNA/metabolismo
16.
Biol Methods Protoc ; 7(1): bpac022, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36157711

RESUMO

Building realistically complex models of infectious disease transmission that are relevant for informing public health is conceptually challenging and requires knowledge of coding architecture that can implement key modeling conventions. For example, many of the models built to understand COVID-19 dynamics have included stochasticity, transmission dynamics that change throughout the epidemic due to changes in host behavior or public health interventions, and spatial structures that account for important spatio-temporal heterogeneities. Here we introduce an R package, SPARSEMODr, that allows users to simulate disease models that are stochastic and spatially explicit, including a model for COVID-19 that was useful in the early phases of the epidemic. SPARSEMOD stands for SPAtial Resolution-SEnsitive Models of Outbreak Dynamics, and our goal is to demonstrate particular conventions for rapidly simulating the dynamics of more complex, spatial models of infectious disease. In this report, we outline the features and workflows of our software package that allow for user-customized simulations. We believe the example models provided in our package will be useful in educational settings, as the coding conventions are adaptable, and will help new modelers to better understand important assumptions that were built into sophisticated COVID-19 models.

17.
R Soc Open Sci ; 9(8): 211953, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35958086

RESUMO

The unchecked spread of misinformation is recognized as an increasing threat to public, scientific and democratic health. Online networks are a contributing cause of this spread, with echo chambers and polarization indicative of the interplay between the search behaviours of users and reinforcement processes within the system they inhabit. Recent empirical work has focused on interventions aimed at inoculating people against misinformation, yielding success on the individual level. However, given the evolving, dynamic information context of online networks, important questions remain regarding how such inoculation interventions interact with network systems. Here we use an agent-based model of a social network populated with belief-updating users. We find that although equally rational agents may be assisted by inoculation interventions to reject misinformation, even among such agents, intervention efficacy is temporally sensitive. We find that as beliefs disseminate, users form self-reinforcing echo chambers, leading to belief consolidation-irrespective of their veracity. Interrupting this process requires 'front-loading' of inoculation interventions by targeting critical thresholds of network users before consolidation occurs. We further demonstrate the value of harnessing tipping point dynamics for herd immunity effects, and note that inoculation processes do not necessarily lead to increased rates of 'false-positive' rejections of truthful communications.

18.
Am J Perinatol ; 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-35858648

RESUMO

OBJECTIVE: The aim of the study is to assess the necessity of chest X-ray (CXR) during the newborn hospitalization for all patients with prenatally suspected congenital pulmonary airway malformation (CPAM). STUDY DESIGN: This is a retrospective chart review of all infants delivered with prenatally suspected CPAM at our high-risk delivery hospital from January 2013 through April 2020 (n = 44). Nonparametric tests assessed the association between postnatal CXR findings, prescribed follow-up timeline, and neonatal outcomes. RESULTS: Mean follow-up period recommended was 6.4 weeks regardless of CXR findings in the neonatal period (p = 0.81). Additionally, patients who required respiratory support at or after birth were not more likely to have a lesion identified on chest X-ray (odds ratio [OR] = 0.72, 95% confidence interval [CI], 0.18-2.64, p = 0.71). CONCLUSION: Neonatal hospital course and future follow-up plan of patients with prenatally suspected CPAM were not altered by information from the CXR obtained in the immediate neonatal period, suggesting that this CXR may not be necessary in the asymptomatic patient. KEY POINTS: · Immediate postnatal X-ray of prenatally diagnosed CPAM does not alter planned follow-up interval.. · Immediate postnatal X-ray does not alter surgical plan for CPAM.. · Postnatal X-ray is not absolutely required for asymptomatic newborns with CPAM..

19.
Methods Appl Fluoresc ; 10(4)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35901806

RESUMO

Correlative imaging methods can provide greater information for investigations of cellular ultra-structure, with separate analysis methods complementing each other's strengths and covering for deficiencies. Here we present a method for correlative applications of super resolution and atomic force microscopies, optimising the sample preparation for correlative imaging of the cellular cytoskeleton in COS-7 cells. This optimisation determined the order of permeabilisation and fixation, the concentration of Triton X-100 surfactant used and time required for sufficient removal of the cellular membrane while maintaining the microtubule network. Correlative SMLM/AFM imaging revealed the different information that can be obtained through each microscopy. The widths of microtubules and microtubule clusters were determined from both AFM height measurements and Gaussian fitting of SMLM intensity cross sections, these were then compared to determine the orientation of microtubules within larger microtubule bundles. The ordering of microtubules at intersections was determined from the AFM height profiles as each microtubule crosses the other. The combination of both microtubule diameter measurements enabled greater information on their structure to be found than either measurement could individually.


Assuntos
Citoesqueleto , Microtúbulos , Animais , Células COS , Chlorocebus aethiops , Microscopia de Força Atômica/métodos
20.
N Engl J Med ; 387(2): 148-159, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35830641

RESUMO

BACKGROUND: Neonatal hypoxic-ischemic encephalopathy is an important cause of death as well as long-term disability in survivors. Erythropoietin has been hypothesized to have neuroprotective effects in infants with hypoxic-ischemic encephalopathy, but its effects on neurodevelopmental outcomes when given in conjunction with therapeutic hypothermia are unknown. METHODS: In a multicenter, double-blind, randomized, placebo-controlled trial, we assigned 501 infants born at 36 weeks or more of gestation with moderate or severe hypoxic-ischemic encephalopathy to receive erythropoietin or placebo, in conjunction with standard therapeutic hypothermia. Erythropoietin (1000 U per kilogram of body weight) or saline placebo was administered intravenously within 26 hours after birth, as well as at 2, 3, 4, and 7 days of age. The primary outcome was death or neurodevelopmental impairment at 22 to 36 months of age. Neurodevelopmental impairment was defined as cerebral palsy, a Gross Motor Function Classification System level of at least 1 (on a scale of 0 [normal] to 5 [most impaired]), or a cognitive score of less than 90 (which corresponds to 0.67 SD below the mean, with higher scores indicating better performance) on the Bayley Scales of Infant and Toddler Development, third edition. RESULTS: Of 500 infants in the modified intention-to-treat analysis, 257 received erythropoietin and 243 received placebo. The incidence of death or neurodevelopmental impairment was 52.5% in the erythropoietin group and 49.5% in the placebo group (relative risk, 1.03; 95% confidence interval [CI], 0.86 to 1.24; P = 0.74). The mean number of serious adverse events per child was higher in the erythropoietin group than in the placebo group (0.86 vs. 0.67; relative risk, 1.26; 95% CI, 1.01 to 1.57). CONCLUSIONS: The administration of erythropoietin to newborns undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy did not result in a lower risk of death or neurodevelopmental impairment than placebo and was associated with a higher rate of serious adverse events. (Funded by the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT02811263.).


Assuntos
Eritropoetina , Hipotermia Induzida , Hipóxia-Isquemia Encefálica , Fármacos Neuroprotetores , Administração Intravenosa , Paralisia Cerebral/etiologia , Método Duplo-Cego , Eritropoetina/administração & dosagem , Eritropoetina/efeitos adversos , Eritropoetina/uso terapêutico , Humanos , Hipotermia Induzida/métodos , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/terapia , Lactente , Recém-Nascido , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/efeitos adversos , Fármacos Neuroprotetores/uso terapêutico
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