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During the metastatic cascade, cancer cells travel through the bloodstream as circulating tumor cells (CTCs) to a secondary site. Clustered CTCs have greater shear stress and treatment resistance, yet their biology remains poorly understood. We therefore engineered a tunable superhydrophobic array device (SHArD). The SHArD-C was applied to culture a clinically relevant model of CTC clusters. Using our device, we cultured a model of cancer cell aggregates of various sizes with immortalized cancer cell lines. These exhibited higher E-cadherin expression and are significantly more capable of surviving high fluid shear stress-related forces compared to single cells and model clusters grown using the control method, helping to explain why clustering may provide a metastatic advantage. Additionally, the SHArD-S, when compared with the AggreWell 800 method, provides a more consistent spheroid-forming device culturing reproducible sizes of spheroids for multiple cancer cell lines. Overall, we designed, fabricated, and validated an easily tunable engineered device which grows physiologically relevant three-dimensional (3D) cancer models containing tens to thousands of cells.
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Interacciones Hidrofóbicas e Hidrofílicas , Células Neoplásicas Circulantes , Humanos , Células Neoplásicas Circulantes/patología , Células Neoplásicas Circulantes/metabolismo , Esferoides Celulares/patología , Esferoides Celulares/metabolismo , Línea Celular Tumoral , Técnicas de Cultivo de Célula/instrumentación , Cadherinas/metabolismoRESUMEN
The efficacy of T cell therapies in treating solid tumors is limited by poor in vivo persistence, proliferation, and cytotoxicity, which can be attributed to limited and variable ex vivo activation. Herein, we present a 10-day kinetic profile of T cells subjected to fluid shear stress (FSS) ex vivo, with and without stimulation utilizing bead-conjugated anti-CD3/CD28 antibodies. We demonstrate that mechanical stimulation via FSS combined with bead-bound anti-CD3/CD28 antibodies yields a synergistic effect, resulting in amplified and sustained downstream signaling (NF-κB, c-Fos, and NFAT), expression of activation markers (CD69 and CD25), proliferation and production of pro-inflammatory cytokines (IFN-γ, TNF-α, and IL-2). This study represents the first characterization of the dynamic response of primary T cells to FSS. Collectively, our findings underscore the critical role of mechanosensitive ion channel-mediated mechanobiological signaling in T cell activation and fitness, enabling the development of strategies to address the current challenges associated with poor immunotherapy outcomes.
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Studying cellular mechanoresponses during cancer metastasis is limited by sample variation or complex protocols that current techniques require. Metastasis is governed by mechanotransduction, whereby cells translate external stimuli, such as circulatory fluid shear stress (FSS), into biochemical cues. We present high-throughput, semi-automated methods to expose cells to FSS using the VIAFLO96 multichannel pipetting device custom-fitted with 22 G needles, increasing the maximum FSS 94-fold from the unmodified tips. Specifically, we develop protocols to semi-automatically stain live samples and to fix, permeabilize, and intracellularly process cells for flow cytometry analysis. Our first model system confirmed that the pro-apoptotic effects of TRAIL therapeutics in prostate cancer cells can be enhanced via FSS-induced Piezo1 activation. Our second system implements this multiplex methodology to show that FSS exposure (290 dyn cm-2) increases activation of murine bone marrow-derived dendritic cells. These methodologies greatly improve the mechanobiology workflow, offering a high-throughput, multiplex approach.
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Mecanotransducción Celular , Neoplasias de la Próstata , Animales , Humanos , Ratones , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/inmunología , Masculino , Células Dendríticas/inmunología , Línea Celular Tumoral , Ensayos Analíticos de Alto Rendimiento/métodos , Estrés Mecánico , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Citometría de Flujo/métodos , Canales IónicosRESUMEN
Viral myocarditis, an inflammatory disease of the heart, causes significant morbidity and mortality. Type I interferon (IFN)-mediated antiviral responses protect against myocarditis, but the mechanisms are poorly understood. We previously identified A Disintegrin And Metalloproteinase domain 9 (ADAM9) as an important factor in viral pathogenesis. ADAM9 is implicated in a range of human diseases, including inflammatory diseases; however, its role in viral infection is unknown. Here, we demonstrate that mice lacking ADAM9 are more susceptible to encephalomyocarditis virus (EMCV)-induced death and fail to mount a characteristic type I IFN response. This defect in type I IFN induction is specific to positive-sense, single-stranded RNA (+ ssRNA) viruses and involves melanoma differentiation-associated protein 5 (MDA5)-a key receptor for +ssRNA viruses. Mechanistically, ADAM9 binds to MDA5 and promotes its oligomerization and thereby downstream mitochondrial antiviral-signaling protein (MAVS) activation in response to EMCV RNA stimulation. Our findings identify a role for ADAM9 in the innate antiviral response, specifically MDA5-mediated IFN production, which protects against virus-induced cardiac damage, and provide a potential therapeutic target for treatment of viral myocarditis.
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Proteínas ADAM , Infecciones por Cardiovirus , Virus de la Encefalomiocarditis , Inmunidad Innata , Interferón Tipo I , Helicasa Inducida por Interferón IFIH1 , Proteínas de la Membrana , Miocarditis , Animales , Ratones , Proteínas ADAM/metabolismo , Proteínas ADAM/genética , Proteínas ADAM/inmunología , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/inmunología , Infecciones por Cardiovirus/inmunología , Infecciones por Cardiovirus/virología , Virus de la Encefalomiocarditis/inmunología , Células HEK293 , Interferón Tipo I/metabolismo , Interferón Tipo I/inmunología , Helicasa Inducida por Interferón IFIH1/metabolismo , Helicasa Inducida por Interferón IFIH1/genética , Helicasa Inducida por Interferón IFIH1/inmunología , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Ratones Endogámicos C57BL , Ratones Noqueados , Miocarditis/inmunología , Miocarditis/virología , Transducción de Señal/inmunologíaRESUMEN
Mounting evidence suggests that the immune landscape within prostate tumors influences progression, metastasis, treatment response, and patient outcomes. In this study, we investigated the spatial density of innate immune cell populations within NOD.SCID orthotopic prostate cancer xenografts following microinjection of human DU145 prostate cancer cells. Our laboratory has previously developed nanoscale liposomes that attach to leukocytes via conjugated E-selectin (ES) and kill cancer cells via TNF-related apoptosis inducing ligand (TRAIL). Immunohistochemistry (IHC) staining was performed on tumor samples to identify and quantify leukocyte infiltration for different periods of tumor growth and E-selectin/TRAIL (EST) liposome treatments. We examined the spatial-temporal dynamics of three different immune cell types infiltrating tumors using QuPath image analysis software. IHC staining revealed that F4/80+ tumor-associated macrophages (TAMs) were the most abundant immune cells in all groups, irrespective of time or treatment. The density of TAMs decreased over the course of tumor growth and decreased in response to EST liposome treatments. Intratumoral versus marginal analysis showed a greater presence of TAMs in the marginal regions at 3 weeks of tumor growth which became more evenly distributed over time and in tumors treated with EST liposomes. TUNEL staining indicated that EST liposomes significantly increased cell apoptosis in treated tumors. Additionally, confocal microscopy identified liposome-coated TAMs in both the core and periphery of tumors, highlighting the ability of liposomes to infiltrate tumors by "piggybacking" on macrophages. The results of this study indicate that TAMs represent the majority of innate immune cells within NOD.SCID orthotopic prostate tumors, and spatial density varies widely as a function of tumor size, duration of tumor growth, and treatment of EST liposomes.
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Liposomas , Ratones Endogámicos NOD , Ratones SCID , Neoplasias de la Próstata , Macrófagos Asociados a Tumores , Animales , Masculino , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/inmunología , Ratones , Humanos , Macrófagos Asociados a Tumores/inmunología , Macrófagos Asociados a Tumores/patología , Ensayos Antitumor por Modelo de Xenoinjerto , Apoptosis , Modelos Animales de Enfermedad , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Selectina E/metabolismo , Microambiente Tumoral/inmunologíaRESUMEN
Objective.Single-photon emission computed tomography (SPECT) with pinhole collimators can provide high-resolution imaging, but is often limited by low sensitivity. Acquiring projections simultaneously through multiple pinholes affords both high resolution and high sensitivity. However, the overlap of projections from different pinholes on detectors, known as multiplexing, has been shown to cause artefacts which degrade reconstructed images.Approach.Multiplexed projection sets were considered here using an analytic simulation model of AdaptiSPECT-C-a brain-dedicated multi-pinhole SPECT system. AdaptiSPECT-C has fully adaptable aperture shutters, so can acquire projections with a combination of multiplexed and non-multiplexed frames using temporal shuttering. Two strategies for reducing multiplex artefacts were considered: an algorithm to de-multiplex projections, and an alternating reconstruction strategy for projections acquired with a combination of multiplexed and non-multiplexed frames. Geometric and anthropomorphic digital phantoms were used to assess a number of metrics.Main results.Both de-multiplexing strategies showed a significant reduction in image artefacts and improved fidelity, image uniformity, contrast recovery and activity recovery (AR). In all cases, the two de-multiplexing strategies resulted in superior metrics to those from images acquired with only mux-free frames. The de-multiplexing algorithm provided reduced image noise and superior uniformity, whereas the alternating strategy improved contrast and AR.Significance.The use of these de-multiplexing algorithms means that multi-pinhole SPECT systems can acquire projections with more multiplexing without degradation of images.
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Artefactos , Procesamiento de Imagen Asistido por Computador , Fantasmas de Imagen , Tomografía Computarizada de Emisión de Fotón Único , Tomografía Computarizada de Emisión de Fotón Único/métodos , Tomografía Computarizada de Emisión de Fotón Único/instrumentación , Procesamiento de Imagen Asistido por Computador/métodos , Factores de Tiempo , Humanos , AlgoritmosRESUMEN
Women and children returning from areas formerly controlled by the Islamic State typically have experienced high levels of trauma and indoctrination, further complicating politically fraught efforts at reintegration and resettlement. Consequently, countries around the world are grappling with how best to manage the return of these women and children. To help better understand which types of programming can contribute to the successful, non-violent reintegration of these individuals, we incorporated ideas from existing Repatriation and Rehabilitation (R&R) literature, field practitioners, R&R subject matter experts, and literature from adjacent fields (e.g., refugee resettlement, criminal justice, psychological resilience) into a recommended best practice approach to supporting returning women and children. We propose a shift from "R&R" programming to what we call the "5R" framework: Repatriation/ Resettlement, Reintegration, Rehabilitation, and Resilience. This shift provides conceptual clarity related to how different program elements target proximal goals (e.g., wellbeing and personal safety, belonging and opportunity, non-violence, and dignity), and how programming can shift from more centrally- and government-held services to informal and community-based supports.
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This rapid review used a systematic approach to examine the available literature on rehabilitation and reintegration (R&R) programs for women and children returning from contexts of violent extremism, examining common assumptions, inputs, activities and outcomes across diverse settings. Fifty-one documents including peer reviewed articles and grey literature were included in the analysis. The most common program activities identified included mental health services, community level social programs, promoting school and vocational enrollment, regular health services, and parenting training & education, though there was a lack of consensus around core program components. The analysis points to the need for a robust set of inputs and resources to implement R&R programs including government officials, child welfare, mental health professionals, teachers, law enforcement, healthcare, community leaders, and extended family. The review also uncovered a number of gaps. This includes the need to create clear and analytically distinct definitions of rehabilitation and reintegration that are applicable and relevant to key stakeholders, delineating age-appropriate activities and outcomes for young children, youth, and adults, defining frameworks for service delivery and coordination of stakeholders, and placing R&R programs within existing domains of public safety and restorative justice.
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Data from the Australian Taxation Office and Australian Border Force show notable recent increases in illicit tobacco seizures across Australia. The illicit tobacco market results in substantial losses in tax revenue, funds organised crime, and perpetuates tobacco use, threatening to undermine Australia's ability to achieve its national commercial tobacco endgame goal of 5 % or less smoking prevalence by 2030. This commentary discusses recent trends in Australia's illicit tobacco trade, reasons why this is of concern, potential drivers of Australians' illicit tobacco use, and policy measures that could be implemented to mitigate increasing illicit tobacco trade such as implementing a track and trace system, increased investment in the Australian Border Force to enhance detection of illicit tobacco shipments at Australia's borders, and encouraging public tip-offs of illicit tobacco sales.
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Comercio , Productos de Tabaco , Humanos , Australia/epidemiología , Comercio/tendencias , Comercio/legislación & jurisprudencia , Productos de Tabaco/economía , Productos de Tabaco/legislación & jurisprudencia , Fumar/epidemiología , Fumar/tendencias , Fumar/economía , Impuestos , Crimen , Industria del Tabaco/economía , Industria del Tabaco/legislación & jurisprudencia , Industria del Tabaco/tendenciasRESUMEN
The remarkable capabilities of generative artificial intelligence and large language models (LLMs) such as ChatGPT have delighted users around the world. Educators have regarded these tools as either a cause for great concern, an opportunity to educate students on cutting-edge technology, or often some combination of the two. Throughout the Fall 2023 semester, we explored the use of ChatGPT (and Bard, among other LLMs) in a graduate level numerical and statistical methods course for PhD-level bioengineers. In this article we share examples of this ChatGPT content, our observations on what worked best in our course, and speculate on how bioengineering students may be best served by this technology in the future.
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The present study examines the influence of technical, physical, and relative age characteristics on players selection success within the Scottish Performance School trials. Ninety adolescent players (81 males, 9 females; mean ± standard deviation: age = 11.3 ± 0.4 years, height = 149.6 ± 6.9 cm, mass 38.1 ± 4.7 kg) performed a battery of physical fitness (20m Sprint, CMJ, 5-0-5 agility test), anthropometric, and 8 small-sided games (SSG; 9v9) as part of a talent identification (TID) programme. Players technical (ball touches, time on the ball, high-speed releases) and locomotor activities (high-speed running distance, sprint distance, accelerations, and decelerations) were monitored using foot-mounted inertial measurements units during SSG's. The data was analysed using independent sample T-tests. Mann-Whitney U analyses were conducted to examine the differences between groups whose data was determined as being (non)parametric, with Cohen effect sizes applied. Successful players performed significantly better during physical tests (Effect size ± confidence limits: Left 5-0-5 = -0.89±0.13, Right 5-0-5 = -0.51±0.11), had significantly higher locomotor activities during SSG (high-intensity distance = 0.4±26.6, horizontal accelerations = 0.59±1.19) and significantly higher technical outputs during SSG (touches = 0.71±6.1, releases = 0.49±2.5, high-speed releases = 0.59±2.7, time on the ball = 0.52±3.4) compared to unsuccessful players. Successful players had significantly higher locomotor activities and technical outputs during SSG than their unsuccessful counterparts. Monitoring technical and locomotor activities during SSG may compliment or replace physical testing batteries for assessing TID processes in soccer.
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Rendimiento Atlético , Carrera , Fútbol , Masculino , Adolescente , Femenino , Humanos , Niño , Aptitud Física , Frecuencia CardíacaRESUMEN
Over the past two decades Biomedical Engineering has emerged as a major discipline that bridges societal needs of human health care with the development of novel technologies. Every medical institution is now equipped at varying degrees of sophistication with the ability to monitor human health in both non-invasive and invasive modes. The multiple scales at which human physiology can be interrogated provide a profound perspective on health and disease. We are at the nexus of creating "avatars" (herein defined as an extension of "digital twins") of human patho/physiology to serve as paradigms for interrogation and potential intervention. Motivated by the emergence of these new capabilities, the IEEE Engineering in Medicine and Biology Society, the Departments of Biomedical Engineering at Johns Hopkins University and Bioengineering at University of California at San Diego sponsored an interdisciplinary workshop to define the grand challenges that face biomedical engineering and the mechanisms to address these challenges. The Workshop identified five grand challenges with cross-cutting themes and provided a roadmap for new technologies, identified new training needs, and defined the types of interdisciplinary teams needed for addressing these challenges. The themes presented in this paper include: 1) accumedicine through creation of avatars of cells, tissues, organs and whole human; 2) development of smart and responsive devices for human function augmentation; 3) exocortical technologies to understand brain function and treat neuropathologies; 4) the development of approaches to harness the human immune system for health and wellness; and 5) new strategies to engineer genomes and cells.
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A recent national survey of bereaved partners found high levels of complicated grief and psychological distress, with evidence that loneliness and isolation may contribute to these outcomes. However, the mechanisms of action for this have not been explored. To advance grief theory this paper reports analysis of the survey free-text data to examine the relationship between social support and emotional responses to bereavement. Individuals bereaved of a civil partner or spouse 6-10 months previously were identified through death registration data. 569/1945 (29 %) completed surveys were received. Of those, 311 participants (55 %) provided responses to two free-text questions which asked about their 'feelings since the death of their partner or spouse', and 'about the support around' them. Data were analysed using corpus-assisted discourse analysis and the discourse dynamics approach for figurative language. Participants described diverse emotional responses to the bereavement (e.g. sadness, anger, denial, acceptance), and the value of formal and informal bereavement support. Although many of the experiences described are accounted for in existing grief theory, some participants described a liminal experience not recognised within these theories. They felt trapped, unable to engage with loss or restoration, and unable to move forward as their planned future no longer existed. They sought out 'communitas' (solidarity in experiences), but often found support from their social networks had diminished. Metaphors were used to describe this liminality, with partner grief expressed as a dark agentic force, a monster, an abyss, and as water. The findings of this study offer original insights into experiences and trajectories of bereavement, and our understandings of prolonged or complicated grief. A novel model 'Between Loss and Restoration' is presented to include these experiences. Recognition of the place for liminality within the spectrum of grief experiences could enhance grief literacy and improve formal and informal bereavement support provision.
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Aflicción , Humanos , Pesar , Ira , Soledad , LenguajeRESUMEN
The development of vaccines for COVID-19 occurred at an unprecedented pace, and 32 vaccines using a broad range of technologies had received authorization for use on an emergency basis by the end of 2021, from either a national regulatory authority or the World Health Organization. However, 27 of those 32 vaccines had little impact on the global course of the pandemic. Only five vaccines, from AstraZeneca, Pfizer/BioNTech, Sinovac, Moderna, and Sinopharm, were manufactured, authorized, and distributed in time to significantly impact the number of deaths worldwide. Together, these five vaccines averted an estimated 17 million deaths in the first year of the vaccination campaign. The shared characteristic of these five manufacturers was their ability to rapidly develop and scale up vaccine production to deliver the large manufacturing volumes required to immunize large segments of the global population. Because the development and manufacturing of these vaccines was generally on the critical path to authorization and supply, the technical activities involved with development, scale-up, testing, technology transfer, and full-scale manufacturing, as well as aspects of the Chemistry, Manufacturing, and Controls (CMC) regulatory interactions, are examined for each vaccine and technology for which information is available in the public domain to provide lessons learned and recommendations on proactive actions to better prepare us for a future pandemic response. The critical success factors include prior experience with commercialization and approval, robust quality systems, rigorous process development strategies, flexible manufacturing facilities with a skilled workforce, collaboration, access to consumables, reagents, and adjuvants (if relevant), and an equitable distribution of the global vaccine manufacturing network.
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COVID-19 , Vacunas contra la Influenza , Humanos , Vacunas contra la COVID-19 , COVID-19/prevención & control , Organización Mundial de la Salud , ComercioRESUMEN
Phase-separated liposomes were used to formulate tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a protein that selectively kills cancer cells while sparing most healthy ones. By controlling the average number of TRAIL molecules per liposome, we demonstrate the ability to tune the formation of TRAIL clusters and their resulting apoptotic activity.
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PURPOSE: In children, the relationship between the dose of intraoperative opioid and postoperative outcomes is unclear. We examined the relationship between intraoperative opioid dose and postanesthesia care unit (PACU) pain scores and opioid and antiemetic administrations. METHODS: We performed a single-institution retrospective cohort study. Patients who were aged < 19 yr, had an American Society of Anesthesiologists Physical Status of I-III, were undergoing one of 11 procedures under general anesthesia and without regional anesthesia, and who were admitted to the PACU were included. Patients were analyzed by quartiles of total intraoperative opioid dose using multivariable regression, adjusting for confounders including procedure. An exploratory analysis of opioid-free anesthetics was also performed. RESULTS: Three thousand, seven hundred and thirty-three cases were included, and the mean age of included patients was 8.3 yr. After adjustment, there were no significant differences between the lowest and higher quartiles for first conscious pain score, mean pain score, PACU opioid dose, or PACU length of stay; in addition, estimated differences were small. Patients in higher quartiles were estimated to be more likely to receive antiemetics, significantly so for those in the second quartile. Patients in the lowest quartile received significantly more intraoperative nonopioid analgesics. In the exploratory analysis, no significant difference in PACU pain scores was found in cases without intraoperative opioids. CONCLUSIONS: Children who received lower doses of intraoperative opioids did not have worse PACU pain outcomes but required fewer antiemetics and received greater numbers of nonopioid analgesics intraoperatively. These findings suggest that lower doses of intraoperative opioids may be administered to children as long as other analgesics are used.
RéSUMé: OBJECTIF: Chez les enfants, la relation entre la dose peropératoire d'opioïdes et les issues postopératoires n'est pas claire. Nous avons examiné la relation entre la dose peropératoire d'opioïdes, les scores de douleur en salle de réveil, et les administrations d'opioïdes et d'antiémétiques. MéTHODE: Nous avons réalisé une étude de cohorte rétrospective dans un seul établissement. Nous avons inclus les patient·es âgé·es < 19 ans ayant un statut physique ASA de I-III et bénéficiant de l'une de 11 interventions sous anesthésie générale et sans anesthésie régionale, et qui avaient été admis·es en salle de réveil. Les patient·es ont été analysé·es par quartiles de la dose totale d'opioïdes peropératoires en utilisant une régression multivariée, en ajustant les données pour tenir compte des facteurs de confusion, notamment de l'intervention. Une analyse exploratoire des anesthésiques sans opioïdes a également été réalisée. RéSULTATS: Au total 3733 cas ont été inclus, et l'âge moyen des enfants était de 8,3 ans. Après ajustement, il n'y avait pas de différences significatives entre les quartiles inférieur et supérieur pour le premier score de douleur chez l'enfant conscient·e, le score de douleur moyen, la dose d'opioïdes en salle de réveil ou la durée du séjour en salle de réveil; de plus, les différences estimées étaient faibles. On a estimé que les patient·es des quartiles supérieurs étaient plus susceptibles de recevoir des antiémétiques et ce, de manière significative pour ceux et celles du deuxième quartile. Les patient·es du quartile inférieur ont reçu significativement plus d'analgésiques non opioïdes peropératoires. Dans l'analyse exploratoire, aucune différence significative dans les scores de douleur en salle de réveil n'a été trouvée dans les cas sans opioïdes peropératoires. CONCLUSION: Les enfants qui ont reçu des doses plus faibles d'opioïdes peropératoires n'ont pas eu de pires issues de douleur en salle de réveil, mais ont eu besoin de moins d'antiémétiques et ont reçu un plus grand nombre d'analgésiques non opioïdes en peropératoire. Ces résultats suggèrent que des doses plus faibles d'opioïdes peropératoires peuvent être administrées aux enfants tant que d'autres analgésiques sont utilisés.
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Analgésicos no Narcóticos , Antieméticos , Niño , Humanos , Analgésicos Opioides , Estudios Retrospectivos , Analgésicos no Narcóticos/uso terapéutico , Antieméticos/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológicoRESUMEN
BACKGROUND: Respiratory motion induces artifacts in reconstructed cardiac perfusion SPECT images. Correction for respiratory motion often relies on a respiratory signal describing the heart displacements during breathing. However, using external tracking devices to estimate respiratory signals can add cost and operational complications in a clinical setting. PURPOSE: We aim to develop a deep learning (DL) approach that uses only SPECT projection data for respiratory signal estimation. METHODS: A modified U-Net was implemented that takes temporally finely sampled SPECT sub-projection data (100 ms) as input. These sub-projections are obtained by reframing the 20-s list-mode data, resulting in 200 sub-projections, at each projection angle for each SPECT camera head. The network outputs a 200-time-point motion signal for each projection angle, which was later aggregated over all angles to give a full respiratory signal. The target signal for DL model training was from an external stereo-camera visual tracking system (VTS). In addition to comparing DL and VTS, we also included a data-driven approach based on the center-of-mass (CoM) strategy. This CoM method estimates respiratory signals by monitoring the axial changes of CoM for counts in the heart region of the sub-projections. We utilized 900 subjects with stress cardiac perfusion SPECT studies, with 302 subjects for testing and the remaining 598 subjects for training and validation. RESULTS: The Pearson's correlation coefficient between the DL respiratory signal and the reference VTS signal was 0.90, compared to 0.70 between the CoM signal and the reference. For respiratory motion correction on SPECT images, all VTS, DL, and CoM approaches partially de-blured the heart wall, resulting in a thinner wall thickness and increased recovered maximal image intensity within the wall, with VTS reducing blurring the most followed by the DL approach. Uptake quantification for the combined anterior and inferior segments of polar maps showed a mean absolute difference from the reference VTS of 1.7% for the DL method for patients with motion >12 mm, compared to 2.6% for the CoM method and 8.5% for no correction. CONCLUSION: We demonstrate the capability of a DL approach to estimate respiratory signal from SPECT projection data for cardiac perfusion imaging. Our results show that the DL based respiratory motion correction reduces artefacts and achieves similar regional quantification to that obtained using the stereo-camera VTS signals. This may enable fully automatic data-driven respiratory motion correction without relying on external motion tracking devices.
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Aprendizaje Profundo , Humanos , Tomografía Computarizada de Emisión de Fotón Único , Corazón/diagnóstico por imagen , Movimiento (Física) , Perfusión , Procesamiento de Imagen Asistido por Computador/métodos , Artefactos , Fantasmas de ImagenRESUMEN
A tumor nano-lysate "TNL" vaccine comprised of sonicated 4T1 cells was developed, characterized and implemented for the prevention of triple-negative breast cancer. This study aimed to gain a better understanding of the immune response behind the success of the vaccine in vivo, through use of ex vivo and in vivo assays. Here, we analyze the activation of various immune cells isolated from healthy mouse spleens and find that antigen-presenting cells (APCs) such as dendritic cells (DCs) are being activated following 24 h incubation with 1:10 mg TNL/mg splenocytes. These cells were further explored to determine the pathway by which activation is occurring, and it was observed that TNL are phagocytosed by DCs to activate NF-kB and c-Fos pathways, resulting in enhanced cytokine release after 24 h. An in vivo temporal analysis was performed in mice to understand the immune response at 1, 3, 7 and 10 days after one 100 µL dose of TNL consisting of 105 sonicated 4T1 cells via cardiac puncture and splenocyte and peripheral blood mononuclear cell (PBMC) analysis. Changes were observed for up to one week. A multiple dose study was performed comparing mice that were vaccinated with one dose of TNL administered every ten days for 3 doses total, as well as a PBS vehicle control. Survival for TNL-vaccinated mice was enhanced compared to the PBS control, and there was an average delay of 10 days in the onset of metastasis. The differences between the groups at the end of the study demonstrate the potential for TNL as a preventative therapeutic.
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Vacunas contra el Cáncer , Neoplasias , Vacunas , Animales , Ratones , Leucocitos Mononucleares , Células Dendríticas , Neoplasias/metabolismo , InmunidadRESUMEN
OBJECTIVES: Radiation segmentectomy using yttrium-90 plays an emerging role in the management of early-stage HCC. However, the value of early post-treatment MRI for response assessment is uncertain. We assessed the value of response criteria obtained early after radiation segmentectomy in predicting long-term response in patients with HCC. MATERIALS AND METHODS: Patients with HCC who underwent contrast-enhanced MRI before, early, and 12 months after radiation segmentectomy were included in this retrospective single-center study. Three independent radiologists reviewed images at baseline and 1st follow-up after radiation segmentectomy and assessed lesion-based response according to mRECIST, LI-RADS treatment response algorithm (TRA), and image subtraction. The endpoint was response at 12 months based on consensus readout of two separate radiologists. Diagnostic accuracy for predicting complete response (CR) at 12 months based on the 1st post-treatment MRI was calculated. RESULTS: Eighty patients (M/F 60/20, mean age 67.7 years) with 80 HCCs were assessed (median size baseline, 1.8 cm [IQR, 1.4-2.9 cm]). At 12 months, 74 patients were classified as CR (92.5%), 5 as partial response (6.3%), and 1 as progressive disease (1.2%). Diagnostic accuracy for predicting CR was fair to good for all readers with excellent positive predictive value (PPV): mRECIST (range between 3 readers, accuracy: 0.763-0.825, PPV: 0.966-1), LI-RADS TRA (accuracy: 0.700-0.825, PPV: 0.983-1), and subtraction (accuracy: 0.775-0.825, PPV: 0.967-1), with no difference in accuracy between criteria (p range 0.053 to > 0.9). CONCLUSION: mRECIST, LI-RADS TRA, and subtraction obtained on early post-treatment MRI show similar performance for predicting long-term response in patients with HCC treated with radiation segmentectomy. CLINICAL RELEVANCE STATEMENT: Response assessment extracted from early post-treatment MRI after radiation segmentectomy predicts complete response in patients with HCC with high PPV (≥ 0.96). KEY POINTS: ⢠Early post-treatment response assessment on MRI predicts response in patients with HCC treated with radiation segmentectomy with fair to good accuracy and excellent positive predictive value. ⢠There was no difference in diagnostic accuracy between mRECIST, LI-RADS, and subtraction for predicting HCC response to radiation segmentectomy.
Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/cirugía , Estudios Retrospectivos , Neumonectomía , Imagen por Resonancia Magnética/métodos , Sensibilidad y Especificidad , Medios de ContrasteRESUMEN
Natural killer (NK) cell functionality is a strong indicator of favorable prognosis in cancer patients, making NK cells an appealing therapeutic target to prevent lymph node dissemination. We engineered liposomes that are conjugated with anti-CD335 antibodies for NK cell targeting, and the apoptotic ligand TRAIL to kill cancer cells. Liposomes were made using a thin film hydration method followed by extrusion to approximately 100 nm in diameter and conjugation of proteins via thiol-maleimide click chemistry. TRAIL/anti-CD335 liposomes successfully bound to isolated NK cells. Once piggybacked to the surface of NK cells, these "Super Natural Killer Cells" were able to more effectively kill oxaliplatin-resistant SW620 cells and metastatic COLO205 colorectal cancer cells via TRAIL-mediated apoptosis compared to NK cells alone. Importantly, Super NK cells were more effective under physiological levels of fluid shear stress found in the lymphatics. Liposome biodistribution after intravenous administration confirmed the sustained presence of liposomes within the spleen and tumor draining mesenteric lymph nodes for at least 4 days. These results demonstrate the enhanced apoptotic effects of NK cells armored with liposomal TRAIL against clinically relevant colorectal cancer cells, providing the groundwork for in vivo treatment studies in mouse models of colorectal cancer metastasis.