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Background: Coronary artery fistula is a rare, but recognized complication of surgical myectomy. Although most communicate with the right heart, a large fistula into the left ventricular cavity may result in a shunt haemodynamically analogous to aortic regurgitation. Understanding the variable presentation of iatrogenic coronary fistulae and the optimal evaluation strategy is critical to obtaining a timely diagnosis and instituting treatment. Case summary: We report the case of a 57-year-old renal transplant recipient admitted for evaluation of presyncope, one-year post-surgical myectomy for hypertrophic obstructive cardiomyopathy. An iatrogenic coronary artery fistula was suspected by transthoracic echocardiography, and later confirmed with both non-invasive and invasive coronary angiography. Discussion: We highlight various cardiac imaging modalities that confirmed the diagnosis of coronary artery fistula and helped to determine the clinical significance. We report the tailored approach often required to determine the anatomic and haemodynamic characteristics of coronary fistulae and outline potential management strategies.
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The agriculture industry lacks novel techniques for analyzing risks facing its workers. Although injuries are common in this field, existing datasets and tools are insufficient for risk assessment and mitigation for two primary reasons: they provide neither immediate nor long-term risk mitigation advice, and they do not account for hazards which fluctuate daily. The purpose of Demeter is to collect safety data about hazards on farms and produce risk analysis and mitigation reports. This application uses a combination of formula-based risk calculations and state-of-the-art graph neural networks (GNNs) to perform risk analysis and reduction. The formula-based risk calculations had a mean absolute error (MAE) of 0.2110, and the GNN had an accuracy of 94.9%, a precision of 0.3521, and a recall of 0.8333. Demeter has the potential to reduce the number of injuries and fatalities among agriculture workers by alerting them to risks present in their daily workflow and suggesting safety precautions.
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Agricultura , Fazendeiros , Humanos , Fazendeiros/estatística & dados numéricos , Medição de Risco/métodos , Agricultura/instrumentação , Acidentes de Trabalho/prevenção & controle , Saúde Ocupacional/normas , Redes Neurais de Computação , Traumatismos Ocupacionais/prevenção & controle , Traumatismos Ocupacionais/epidemiologiaRESUMO
A 70-year-old female presented with an 8-month history of right anterior shoulder pain and weakness, unresolved with conservative management. Among other shoulder pathology, the patient was diagnosed with a full-thickness supraspinatus tear and elected to proceed with the microfragmented adipose tissue procedure to treat the injured tendon and nearby relevant structures. Improvements in pain and function were documented along with progressive healing of the supraspinatus on ultrasound and MRI following the procedure. This case demonstrates the efficacy of microfragmented adipose tissue as a relatively novel approach to treating non-retracted, full-thickness rotator cuff tears.
Fat is an excellent source of stem cells and collagen protein fibers known as a matrix. Mesenchymal stem cells can differentiate into a variety of other cell types. Collagen provides structure and is a major component of muscles and tendons. When transferring stem cells from one's own fat, these cells can support the body's repair process of injured tissue, such as rotator cuff tears of the shoulder. In this case, a patient with a long history of shoulder pain and weakness was diagnosed with a full-thickness tear of one of the four muscles that make up the rotator cuff. Full-thickness tears, compared with partial-thickness tears, are larger, deeper tears that extend across the tendon. This is an injury that has historically been limited to either conservative management (living with the pain) or surgery. The patient underwent a nonsurgical alternative, known as the microfragmented adipose tissue procedure, to repair the injured tendon. Fat was transferred from her hips and injected into the rotator cuff tear of the shoulder. She experienced improvements in pain and function as the tendon healed, documented using ultrasound and MRI. This case supports the benefit of microfragmented adipose tissue, a newer, less invasive approach to treating musculoskeletal injuries, even those as severe as a full-thickness rotator cuff tear.
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We present evidence that Earvin "Magic" Johnson's announcement that he contracted HIV served as a public-health catalyst for rapidly correcting the public's understanding of who was at risk of infection. Using a novel identification strategy, we present evidence that there was a large but temporary increase in the number of AIDS diagnoses for heterosexual men following the announcement. This effect was concentrated in areas with greater prior exposure to Johnson. We show that these men were both more likely to have been diagnosed via a formal blood test and less likely to die within 1 decade of their initial diagnosis-suggesting that Johnson's announcement caused an intertemporal substitution in testing which prolonged patients' lifespans as a result of earlier access to medical care. We estimate that Johnson's announcement caused approximately 800 additional heterosexual males in the United States in metropolitan statistical areas with National Basketball Association franchises men to discover their underlying AIDS diagnosis and, of whom, were more likely to live at least 1 decade beyond their initial diagnosis date.
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Síndrome da Imunodeficiência Adquirida , Basquetebol , Pessoas Famosas , Infecções por HIV , Masculino , Humanos , Estados Unidos , Síndrome da Imunodeficiência Adquirida/diagnóstico , Saúde Pública , Infecções por HIV/diagnósticoRESUMO
The development of new materials and their compositional and microstructural optimization are essential in regard to next-generation technologies such as clean energy and environmental sustainability. However, materials discovery and optimization have been a frustratingly slow process. The Edisonian trial-and-error process is time consuming and resource inefficient, particularly when contrasted with vast materials design spaces1. Whereas traditional combinatorial deposition methods can generate material libraries2,3, these suffer from limited material options and inability to leverage major breakthroughs in nanomaterial synthesis. Here we report a high-throughput combinatorial printing method capable of fabricating materials with compositional gradients at microscale spatial resolution. In situ mixing and printing in the aerosol phase allows instantaneous tuning of the mixing ratio of a broad range of materials on the fly, which is an important feature unobtainable in conventional multimaterials printing using feedstocks in liquid-liquid or solid-solid phases4-6. We demonstrate a variety of high-throughput printing strategies and applications in combinatorial doping, functional grading and chemical reaction, enabling materials exploration of doped chalcogenides and compositionally graded materials with gradient properties. The ability to combine the top-down design freedom of additive manufacturing with bottom-up control over local material compositions promises the development of compositionally complex materials inaccessible via conventional manufacturing approaches.
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There is a pressing need for the standardization of orthobiologics, considering the cellular components, concentrations, and methods of injections may vary wildly, currently without significant standards of care. There is a growing body of evidence that these factors matter significantly for patient outcomes, so it is imperative that orthobiologic constituents are measured and standardized. Cell counts may be performed for platelet-rich plasma and bone marrow aspirate-based injections, whereas adipose should have standardized processing techniques as cellular quantification is more difficult.
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Plasma Rico em Plaquetas , Humanos , Tecido Adiposo , Injeções , Padrões de ReferênciaRESUMO
Our patient presented with a 1-year history of right sided Achilles tendon pain and weakness due to partial intrasubstance tear. The injury was refractory to conservative treatment, leading to a trial injection of microfragmented adipose tissue. Progressive healing and improved function were documented on physical exam and sonographically at subsequent follow-up appointments. About 4 weeks following the injection, the patient was able to return to his regular activity level. At the 6 month follow-up appointment, the patient continued to be pain free and had resumed all prior activities without limitations. This case highlights the potential microfragmented adipose tissue has as a regenerative treatment modality for the management of partial Achilles tendon tears.
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Tendão do Calcâneo , Tendão do Calcâneo/lesões , Adipócitos , Tecido Adiposo , Humanos , Ruptura , CicatrizaçãoRESUMO
Cancer cells thrive when embedded in a fine-tuned cellular and extracellular environment or tumour microenvironment (TME). There is a general understanding of a co-evolution between cancer cells and their surrounding TME, pointing at a functional connection between cancer cells characteristics and the perturbations induced in their surrounding tissue. However, it has never been formally proven whether this functional connection needs to be set from the start or if aggressive cancer cells always dominate their microenvironmental any point in time. This would require a dedicated experimental setting where malignant cells are challenged to grow in a different TME from the one they would naturally create. Here we generated an experimental setting where we transiently perturb the secretory profile of aggressive breast cancer cells without affecting their intrinsic growth ability, which led to the initial establishment of an atypical TME. Interestingly, even if initially tumours are formed, this atypical TME evolves to impair long term in vivo cancer growth. Using a combination of in vivo transcriptomics, protein arrays and in vitro co-cultures, we found that the atypical TME culminates in the infiltration of macrophages with STAT1high activity. These macrophages show strong anti-tumoural functions which reduce long-term tumour growth, despite lacking canonical M1 markers. Importantly, gene signatures of the mesenchymal compartment of the TME, as well as the anti-tumoural macrophages, show striking prognostic power that correlates with less aggressive human breast cancers.
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Neoplasias da Mama , Microambiente Tumoral , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Humanos , Macrófagos/patologiaRESUMO
Complex tasks like hunting moving prey in an unpredictable environment require high levels of motor and sensory integration. An animal needs to detect and track suitable prey objects, measure their distance and orientation relative to its own position, and finally produce the correct motor output to approach and capture the prey. In the insect brain, the central complex (CX) is one target area where integration is likely to take place. In this study, we performed extracellular multi-unit recordings on the CX of freely hunting praying mantises (Tenodera sinensis). Initially, we recorded the neural activity of freely moving mantises as they hunted live prey. The recordings showed activity in cells that either reflected the mantis's own movements or the actions of a prey individual, which the mantises focused on. In the latter case, the activity increased as the prey moved and decreased when it stopped. Interestingly, cells ignored the movement of the other prey than the one to which the mantis attended. To obtain quantitative data, we generated simulated prey targets presented on an LCD screen positioned below the clear floor of the arena. The simulated target oscillated back and forth at various angles and distances. We identified populations of cells whose activity patterns were strongly linked to the appearance, movement, and relative position of the virtual prey. We refer to these as sensory responses. We also found cells whose activity preceded orientation movement toward the prey. We call these motor responses. Some cells showed both sensory and motor properties. Stimulation through tetrodes in some of the preparations could also generate similar movements. These results suggest the crucial importance of the CX to prey-capture behavior in predatory insects like the praying mantis and, hence, further emphasize its role in behaviorally and ecologically relevant contexts.
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Mantódeos , Animais , Mantódeos/fisiologia , Movimento , Neurônios , Comportamento Predatório/fisiologiaRESUMO
Visual illusions provide a compelling case for the idea that perception and belief may remain incongruent. This can be explained by modular theories of mind, but it is not straightforwardly accommodated by the Predictive Processing framework, which takes perceptual and cognitive predictions to derive from the same underlying inferential hierarchy. Recent insights concerning the neural implementation of Predictive Processing may help elucidate this. Specifically, prior information is proposed to be approximated by mechanisms in both the top-down and bottom-up streams of information processing. While the former is context-dependent and flexible in updating, the latter is context-independent and difficult to revise. We propose that a stable divergence between perception and belief may emerge when flexible prior information at higher hierarchical levels contradicts inflexible prior information at lower ones. This allows Predictive Processing to account for conflicting percepts and beliefs while still maintaining a hierarchical and unitary conception of cognition.
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Cognição , Ilusões , Humanos , Percepção VisualRESUMO
While developing boron-catalyzed glycosylations using glycosyl fluoride donors and trialkylsilyl ether acceptors, competing pathways involving productive glycosylation or glycosyl exchange were observed. Experimental and computational mechanistic studies suggest a novel mode of reactivity where a dioxolenium ion is a key intermediate that promotes both pathways through addition to either a silyl ether or to the acetal of an existing glycosidic linkage. Modifications in catalyst structure enable either pathway to be favored, and with this understanding, improved multicomponent iterative couplings and glycosyl exchange processes were demonstrated.
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Éteres , Glicosídeos , Catálise , Glicosídeos/química , Glicosilação , EstereoisomerismoRESUMO
Coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus is likely to remain endemic globally despite widespread vaccination. There is increasing concern for myocardial involvement and ensuing cardiac complications due to COVID-19, however, the available evidence suggests these risks are low. Pandemic publishing has resulted in rapid manuscript availability though pre-print servers. Subsequent article retractions, a lack of standardised definitions, over-reliance on isolated troponin elevation and the heterogeneity of studied patient groups (i.e. severe vs. symptomatic vs all infections) resulted in early concern for high rates of myocarditis in patients with and recovering from COVID-19. The estimated incidence of myocarditis in COVID-19 infection is 11 cases per 100,000 infections compared with an estimated 2.7 cases per 100,000 persons following mRNA vaccination. For substantiated cases, the clinical course of myocarditis related to COVID-19 or mRNA vaccination appears mild and self-limiting, with reports of severe/fulminant myocarditis being rare. There is limited data available on the management of myocarditis in these settings. Clinical guidance for appropriate use of cardiac investigations and monitoring in COVID-19 is needed for effective risk stratification and efficient use of cardiac resources in Australia. An amalgamation of national and international position statements and guidelines is helpful for guiding clinical practice. This paper reviews the current available evidence and guidelines and provides a summary of the risks and potential use of cardiac investigations and monitoring for patients with COVID-19.
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COVID-19 , Cardiopatias , Miocardite , COVID-19/complicações , COVID-19/epidemiologia , COVID-19/prevenção & controle , Humanos , Miocardite/epidemiologia , Miocardite/etiologia , RNA Mensageiro , SARS-CoV-2 , VacinaçãoRESUMO
Cell migration is crucial for efficient immune responses and is aberrantly used by cancer cells during metastatic dissemination. Amoeboid migrating cells use myosin II-powered blebs to propel themselves, and change morphology and direction. Immune cells use amoeboid strategies to respond rapidly to infection or tissue damage, which require quick passage through several barriers, including blood, lymph and interstitial tissues, with complex and varied environments. Amoeboid migration is also used by metastatic cancer cells to aid their migration, dissemination and survival, whereby key mechanisms are hijacked from professionally motile immune cells. We explore important parallels observed between amoeboid immune and cancer cells. We also consider key distinctions that separate the lifespan, state and fate of these cell types as they migrate and/or fulfil their function. Finally, we reflect on unexplored areas of research that would enhance our understanding of how tumour cells use immune cell strategies during metastasis, and how to target these processes.
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Quaternary chalcogenides continue to be of interest due to the variety of physical properties they possess, as well as their potential for different applications of interest. Investigations on materials with the sphalerite crystal structure have only recently begun. In this study we have synthesized sulfur-based sphalerite quaternary chalcogenides, including off-stoichiometric compositions, and investigated the temperature-dependent electronic, thermal and structural properties of these materials. Insulating to semiconducting transport is observed with stoichiometric variation, and analyses of heat capacity and thermal expansion revealed lattice anharmonicity that contributes to the low thermal conductivity these materials possess. We include similar analyses for CuZn2InSe4 and compare these sphalerite quaternary chalcogenides to that of zinc blende binaries in order to fully understand the origin of the low thermal conductivity these quaternary chalcogenides possess.
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Meditation is an umbrella term for a number of mental training practices designed to improve the monitoring and regulation of attention and emotion. Some forms of meditation are now being used for clinical intervention. To accompany the increased clinical interest in meditation, research investigating the neural basis of these practices is needed. A central hypothesis of contemplative neuroscience is that meditative states, which are unique on a phenomenological level, differ on a neurophysiological level. To identify the electrophysiological correlates of meditation practice, the electrical brain activity of highly skilled meditators engaging in one of six meditation styles (shamatha, vipassana, zazen, dzogchen, tonglen, and visualization) was recorded. A mind-wandering task served as a control. Lempel-Ziv complexity showed differences in nonlinear brain dynamics (entropy) during meditation compared with mind wandering, suggesting that meditation, regardless of practice, affects neural complexity. In contrast, there were no differences in power spectra at six different frequency bands, likely due to the fact that participants engaged in different meditation practices. Finally, exploratory analyses suggest neurological differences among meditation practices. These findings highlight the importance of studying the electroencephalography (EEG) correlates of different meditative practices.
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This work describes select narratives pertaining to undergraduate teaching and mentorship at UCLA Chemistry and Biochemistry by Alex Spokoyny and his junior colleagues. Specifically, we discuss how individual undergraduate researchers contributed and jump-started multiple research themes since the conception of our research laboratory. This work also describes several recent innovations in the inorganic and general chemistry courses taught by Spokoyny at UCLA with a focus of nurturing appreciation for research and creative process in sciences including the use of social media platforms.
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This case series describes the effect of angiotensin II administration on hemodynamics in patients with parenchymal lung injury due to submersion injury. CASE SUMMARY: A 33-year-old female and a 72-year-old female were both brought to the emergency department after incidents of near drowning. Upon arrival to the emergency department, both patients were hemodynamically unstable and were eventually intubated for airway protection. Imaging done by conventional chest radiograph for both patients revealed bilateral pulmonary edema. Due to their hemodynamic status, vasopressors were initiated for both patients and were quickly titrated, leading to the initiation of angiotensin II. In one patient, angiotensin II was initiated early in shock and resulted in rapid improvement of hemodynamics. In the other patient, angiotensin II was initiated later and a more muted response was observed. CONCLUSIONS: In patients with near drowning, angiotensin II appeared to improve hemodynamic status rapidly. This is the first case series to report the use of this new vasoactive agent in this population and poses noteworthy mechanistic considerations.
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According to the predictive processing framework, perception is geared to represent the environment in terms of embodied action opportunities as opposed to objective truth. Here, we argue that such an optimisation is reflected by biases in expectations (i.e., prior predictive information) that facilitate 'useful' inferences of external sensory causes. To support this, we highlight a body of literature suggesting that perception is systematically biased away from accurate estimates under conditions where utility and accuracy conflict with one another. We interpret this to reflect the brain's attempt to adjudicate between conflicting sources of prediction error, as external accuracy is sacrificed to facilitate actions that proactively avoid physiologically surprising outcomes. This carries important theoretical implications and offers new insights into psychopathology.