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1.
Free Radic Biol Med ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39097206

RESUMEN

AIM: High-resolution respirometry in human permeabilized muscle fibers is extensively used for analysis of mitochondrial adaptions to nutrition and exercise interventions, and is linked to athletic performance. However, the lack of standardization of experimental conditions limits quantitative inter- and intra-laboratory comparisons. METHODS: In our study, an international team of investigators measured mitochondrial respiration of permeabilized muscle fibers obtained from three biopsies (vastus lateralis) from the same healthy volunteer to avoid inter-individual variability. High-resolution respirometry assays were performed together at the same laboratory to assess whether the heterogenity in published results are due to the effects of respiration media (MiR05 versus Z) with or without the myosin inhibitor blebbistatin at low- and high-oxygen regimes. RESULTS: Our findings reveal significant differences between respiration media for OXPHOS and ET capacities supported by NADH&succinate-linked substrates at different oxygen concentrations. Respiratory capacities were approximately 1.5-fold higher in MiR05 at high-oxygen regimes compared to medium Z near air saturation. The presence or absence of blebbistatin in human permeabilized muscle fiber preparations was without effect on oxygen flux. CONCLUSION: Our study constitutes a basis to harmonize and establish optimum experimental conditions for respirometric studies of permeabilized human skeletal muscle fibers to improve reproducibility.

2.
Clin Res Cardiol ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39102002

RESUMEN

BACKGROUND: Evidence supporting pre-hospital heparin administration in patients with suspected non-ST segment elevation acute coronary syndrome (NSTE-ACS) is lacking. We aim to evaluate if pre-hospital heparin administration by emergency medical service improves clinical outcome in patients with suspected NSTE-ACS. METHODS: Patients with suspected myocardial infarction (MI) presenting to the emergency department were prospectively enrolled from 2013 to 2021, excluding those with ST segment elevation MI. Patients with and without prehospital heparin administration were compared using propensity score matching. To assess the association between pre-hospital heparin loading, 30-day and 1-year mortality, Kaplan-Meier estimations and Cox regression models were used. RESULTS: Among 1,234 patients, median age was 69 years, 755 (61.2%) were male, 867 (70.5%) with known hypertension, 177 (14.4%) had diabetes, 280 (23.1%) were current smokers, and 444 (36.0%) had a history of CAD. Compared to patients without pre-hospital heparin administration, heparin pre-treated patients were more often active smokers (26.5% vs. 20.8%). After propensity matching, 475 patients with vs. without pre-hospital heparin administration were compared, with no significant difference in 30-day mortality (no-heparin 1.3% vs. heparin 0.4%) and 1-year mortality (no-heparin 7.2% vs. heparin 5.5%, adjusted HR 0.98, CI 0.95-1.01, p = 0.22). Bleeding events occurred at a low frequency (< 2%) and did not differ between groups. CONCLUSIONS: In this study, pre-hospital heparin administration was not associated with improved clinical outcome in patients with suspected NSTE-ACS. These findings question pre-hospital heparin therapy in this patient population and might potentially warrant a more restricted utilization pending in-hospital risk assessment.

3.
BMC Med Educ ; 24(1): 843, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39107748

RESUMEN

BACKGROUND: Point of care ultrasound (POCUS) education has grown significantly over the past two decades. Like most curricular items, POCUS education is siloed within individual graduate medical education (GME) programs. The purpose of this study was to evaluate the effectiveness of a shared GME POCUS curriculum between five GME programs at a single institution. METHODS: Post-graduate-year-1 (PGY-1) residents from emergency medicine (EM), family medicine (FM), internal medicine (IM), combined internal medicine-pediatrics (IM-Peds) and combined emergency medicine-pediatrics (EM-Peds) residency programs were enrolled in a core POCUS curriculum. The curriculum included eleven asynchronous online learning modules and ten hands-on training sessions proctored by sonographers and faculty physicians with POCUS expertise. Data was gathered about the curriculum's effectiveness including participation, pre- and post-curricular surveys, pre- and post-knowledge assessments, and an objective skills assessment. RESULTS: Of the 85 residents enrolled, 61 (72%) participated in the curriculum. Engagement varied between programs, with attendance at hands-on sessions varying the most (EM 100%, EM-Peds 100%, FM 40%, IM 22%, Med-Peds 11%). Pre- and post-knowledge assessment scores improved for all components of the curriculum. Participants felt significantly more confident with image acquisition, anatomy recognition, interpreting images and incorporating POCUS findings into clinical practice (p < 0.001) after completing the curriculum. CONCLUSION: In this shared GME POCUS curriculum, we found significant improvement in POCUS knowledge, attitudes, and psychomotor skills. This shared approach may be a viable way for other institutions to provide POCUS education broadly to their GME programs.


Asunto(s)
Competencia Clínica , Curriculum , Educación de Postgrado en Medicina , Internado y Residencia , Sistemas de Atención de Punto , Ultrasonografía , Humanos , Evaluación Educacional
4.
Radiographics ; 44(8): e240129, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39088360

RESUMEN

Editor's Note.-RadioGraphics Update articles supplement or update information found in full-length articles previously published in RadioGraphics. These updates, written by at least one author of the previous article, provide a brief synopsis that emphasizes important new information such as technological advances, revised imaging protocols, new clinical guidelines involving imaging, or updated classification schemes.


Asunto(s)
Hiperparatiroidismo Primario , Tomografía Computarizada por Rayos X , Humanos , Hiperparatiroidismo Primario/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Guías de Práctica Clínica como Asunto
5.
bioRxiv ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39091784

RESUMEN

Secondary contact between previously allopatric lineages offers a test of reproductive isolating mechanisms that may have accrued in isolation. Such instances of contact can produce stable hybrid zones-where reproductive isolation can further develop via reinforcement or phenotypic displacement-or result in the lineages merging. Ongoing secondary contact is most visible in continental systems, where steady input from parental taxa can occur readily. In oceanic island systems, however, secondary contact between closely related species of birds is relatively rare. When observed on sufficiently small islands, relative to population size, secondary contact likely represents a recent phenomenon. Here, we examine the dynamics of a group of birds whose apparent widespread hybridization influenced Ernst Mayr's foundational work on allopatric speciation: the whistlers of Fiji (Aves: Pachycephala ). We demonstrate two clear instances of secondary contact within the Fijian archipelago, one resulting in a hybrid zone on a larger island, and the other resulting in a wholly admixed population on a smaller, adjacent island. We leveraged low genome-wide divergence in the hybrid zone to pinpoint a single genomic region associated with observed phenotypic differences. We use genomic data to present a new hypothesis that emphasizes rapid plumage evolution and post-divergence gene flow.

6.
bioRxiv ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39091796

RESUMEN

The corpus callosum (CC) is the largest set of white matter fibers connecting the two hemispheres of the brain. In humans, it is essential for coordinating sensorimotor responses, performing associative/executive functions, and representing information in multiple dimensions. Understanding which genetic variants underpin corpus callosum morphometry, and their shared influence on cortical structure and susceptibility to neuropsychiatric disorders, can provide molecular insights into the CC's role in mediating cortical development and its contribution to neuropsychiatric disease. To characterize the morphometry of the midsagittal corpus callosum, we developed a publicly available artificial intelligence based tool to extract, parcellate, and calculate its total and regional area and thickness. Using the UK Biobank (UKB) and the Adolescent Brain Cognitive Development study (ABCD), we extracted measures of midsagittal corpus callosum morphometry and performed a genome-wide association study (GWAS) meta-analysis of European participants (combined N = 46,685). We then examined evidence for generalization to the non-European participants of the UKB and ABCD cohorts (combined N = 7,040). Post-GWAS analyses implicate prenatal intracellular organization and cell growth patterns, and high heritability in regions of open chromatin, suggesting transcriptional activity regulation in early development. Results suggest programmed cell death mediated by the immune system drives the thinning of the posterior body and isthmus. Global and local genetic overlap, along with causal genetic liability, between the corpus callosum, cerebral cortex, and neuropsychiatric disorders such as attention-deficit/hyperactivity and bipolar disorders were identified. These results provide insight into variability of corpus callosum development, its genetic influence on the cerebral cortex, and biological mechanisms related to neuropsychiatric dysfunction.

7.
J Neurooncol ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093532

RESUMEN

OBJECTIVES: Standard of care treatment for glioblastoma (GBM) involves surgical resection followed by chemoradiotherapy. However, variations in treatment decisions and outcomes exist across hospitals and physicians. In Belgium, where oncological care is dispersed, the impact of hospital volume on GBM outcomes remains unexplored. This nationwide study aims to analyse interhospital variability in 30-day postoperative mortality and 1-/2-year survival for GBM patients. METHODS: Data collected from the Belgian Cancer Registry, identified GBM patients diagnosed between 2016 and 2019. Surgical resection and biopsy cases were identified, and hospital case load was determined. Associations between hospital volume and mortality and survival probabilities were analysed, considering patient characteristics. Statistical analysis included logistic regression for mortality and Cox proportional hazard models for survival. RESULTS: A total of 2269 GBM patients were identified (1665 underwent resection, 662 underwent only biopsy). Thirty-day mortality rates post-resection/post-biopsy were 5.1%/11.9% (target < 3%/<5%). Rates were higher in elderly patients and those with worse WHO-performance scores. No significant difference was found based on hospital case load. Survival probabilities at 1/2 years were 48.6% and 21.3% post-resection; 22.4% and 8.3% post-biopsy. Hazard ratio for all-cause death for low vs. high volume centres was 1.618 in first 0.7 year post-resection (p < 0.0001) and 1.411 in first 0.8 year post-biopsy (p = 0.0046). CONCLUSION: While 30-day postoperative mortality rates were above predefined targets, no association between hospital volume and mortality was found. However, survival probabilities demonstrated benefits from treatment in higher volume centres, particularly in the initial months post-surgery. These variations highlight the need for continuous improvement in neuro-oncological practice and should stimulate reflection on the neuro-oncological care organisation in Belgium.

8.
Nat Med ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39095597

RESUMEN

The leishmaniases are globally important parasitic diseases for which no human vaccines are currently available. To facilitate vaccine development, we conducted an open-label observational study to establish a controlled human infection model (CHIM) of sand fly-transmitted cutaneous leishmaniasis (CL) caused by Leishmania major. Between 24 January and 12 August 2022, we exposed 14 participants to L. major-infected Phlebotomus duboscqi. The primary objective was to demonstrate effectiveness of lesion development (take rate) and safety (absence of CL lesion at 12 months). Secondary and exploratory objectives included rate of lesion development, parasite load and analysis of local immune responses by immunohistology and spatial transcriptomics. Lesion development was terminated by therapeutic biopsy (between days 14 and 42 after bite) in ten participants with clinically compatible lesions, one of which was not confirmed by parasite detection. We estimated an overall take rate for CL development of 64% (9/14). Two of ten participants had one and one of ten participants had two lesion recurrences 4-8 months after biopsy that were treated successfully with cryotherapy. No severe or serious adverse events were recorded, but as expected, scarring due to a combination of CL and the biopsy procedure was evident. All participants were lesion free at >12-month follow-up. We provide the first comprehensive map of immune cell distribution and cytokine/chemokine expression in human CL lesions, revealing discrete immune niches. This CHIM offers opportunities for vaccine candidate selection based on human efficacy data and for a greater understanding of immune-mediated pathology. ClinicalTrials.gov identifier: NCT04512742 .

9.
Head Neck Pathol ; 18(1): 67, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39101976

RESUMEN

BACKGROUND: High-risk human papillomavirus (HR-HPV) infection has been increasingly recognized as a risk factor for sinonasal tract carcinomas. However the prevalence and prognostic significance of HPV-associated sinonasal carcinomas is not well known due to limited studies and inconsistency in HPV testing modalities in literatures. Morphologically, HPV-associated sinonasal carcinomas encompass a diverse group of tumors. HPV-associated sinonasal adenocarcinoma has not been reported. The purpose of this study was to determine the prevalence, morphologic spectrum and prognostic implication of HPV-associated sinonasal carcinomas. METHODS: This cohort included 153 sinonasal carcinomas. Tissue microarrays were constructed. P16 immunohistochemistry and HR-HPV E6/7 in-situ Hybridization (ISH) were performed. Carcinomas were deemed HPV-associated based on a positive ISH testing. Clinicopathologic data was collected. RESULTS: 28/153 (18%) sinonasal carcinomas were HPV-associated. HPV-associated carcinomas consisted of 26 (93%) squamous cell carcinomas and variants, 1 (3.5%) HPV-related multiphenotypic sinonasal carcinoma and 1 (3.5%) adenocarcinoma. The HPV-associated adenocarcinoma closely resembled HPV-associated endocervical adenocarcinoma morphologically. HPV-associated carcinomas occurred in 8 (29%) women and 20 (71%) men with a median age of 66 years old. HPV-associated carcinomas were predominantly located at nasal cavity. A trend toward improved overall survival and progression free survival in HPV-associated carcinomas patients was observed, yet without statistical significance. CONCLUSION: Our study identifies a novel HPV-associated sinonasal adenocarcinoma subtype, highlights the broad morphologic spectrum of HPV-associated sinonasal carcinomas, and supports routine p16 testing during pathology practice regardless of tumor subtype followed by a confirmatory HR-HPV testing. This practice is critical for studying the clinical behavior of HPV-associated sinonasal carcinomas.


Asunto(s)
Infecciones por Papillomavirus , Neoplasias de los Senos Paranasales , Humanos , Masculino , Femenino , Infecciones por Papillomavirus/complicaciones , Anciano , Persona de Mediana Edad , Neoplasias de los Senos Paranasales/virología , Neoplasias de los Senos Paranasales/patología , Adulto , Anciano de 80 o más Años , Adenocarcinoma/virología , Adenocarcinoma/patología
10.
Gigascience ; 132024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-39102518

RESUMEN

A large range of sophisticated brain image analysis tools have been developed by the neuroscience community, greatly advancing the field of human brain mapping. Here we introduce the Computational Anatomy Toolbox (CAT)-a powerful suite of tools for brain morphometric analyses with an intuitive graphical user interface but also usable as a shell script. CAT is suitable for beginners, casual users, experts, and developers alike, providing a comprehensive set of analysis options, workflows, and integrated pipelines. The available analysis streams-illustrated on an example dataset-allow for voxel-based, surface-based, and region-based morphometric analyses. Notably, CAT incorporates multiple quality control options and covers the entire analysis workflow, including the preprocessing of cross-sectional and longitudinal data, statistical analysis, and the visualization of results. The overarching aim of this article is to provide a complete description and evaluation of CAT while offering a citable standard for the neuroscience community.


Asunto(s)
Encéfalo , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Programas Informáticos , Imagen por Resonancia Magnética/métodos , Humanos , Encéfalo/diagnóstico por imagen , Encéfalo/anatomía & histología , Procesamiento de Imagen Asistido por Computador/métodos , Mapeo Encefálico/métodos , Biología Computacional/métodos , Neuroimagen/métodos
11.
Front Cell Neurosci ; 18: 1408208, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39104440

RESUMEN

Introduction: Exposure to heavy metal lead can cause serious health effects such as developmental neurotoxicity in infants, cognitive impairment in children, and cardiovascular and nephrotoxic effects in adults. Hearing loss is one of the toxic effects induced by exposure to lead. Previous studies demonstrated that exposure to lead causes oxidative stress in the cochlea and disrupts ribbon synapses in the inner hair cells. Methods: This study investigated the underlying mechanism by evaluating the changes in the abundance of cochlear synaptosomal proteins that accompany lead-induced cochlear synaptopathy and hearing loss in mice. Young-adult CBA/J mice were given lead acetate in drinking water for 28 days. Results: Lead exposure significantly increased the hearing thresholds, particularly at the higher frequencies in both male and female mice, but it did not affect the activity of outer hair cells or induce hair cell loss. However, lead exposure decreased wave-I amplitude, suggesting lead-induced cochlear synaptopathy. In agreement, colocalization of pre- and post-synaptic markers indicated that lead exposure decreased the number of paired synapses in the basal turn of the cochlea. Proteomics analysis indicated that lead exposure increased the abundance of 352 synaptic proteins and decreased the abundance of 394 synaptic proteins in the cochlea. Bioinformatics analysis indicated that proteins that change in abundance are highly enriched in the synaptic vesicle cycle pathway. Discussion: Together, these results suggest that outer hair cells are not the primary target in lead-induced ototoxicity, that lead-induced cochlear synaptopathy is more pronounced in the basal turn of the cochlea, and that synaptic vesicle cycle signaling potentially plays a critical role in lead-induced cochlear synaptopathy.

12.
Lancet Reg Health Am ; 37: 100837, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39105140

RESUMEN

Background: Most Americans believe that gun-free zones make locations more vulnerable to violent crimes, particularly active shootings. However, there is no empirical evidence regarding the impact of gun-free zones on protecting locations from violence. The objective of this study was to estimate the association between gun-free zones and active shootings. Methods: We used a pair-matched case-control study where cases were all US establishments where active shootings occurred between 2014 and 2020, and controls were randomly selected US establishments where active shootings could have but did not occur, pair-matched by establishment type, year, and county. Gun-free status of included establishments was determined via local laws, company policy, news reporting, Google Maps and posted signage, and calling establishments. Findings: Of 150 active shooting cases, 72 (48.0%) were determined to have occurred in a gun-free zone. Of 150 controls where no active shooting occurred, 92 (61.3%) were determined to be gun-free. After accounting for matched pairs, the conditional odds of an active shooting in gun-free establishments were 0.38 times those in non-gun-free establishments, with a 95% confidence interval of 0.19-0.73 (p-value = 0.0038). Several robustness analyses affirmed these findings. Interpretation: It is unlikely that gun-free zones attract active shooters; gun-free zones may be protective against active shootings. This study challenges the proposition of repealing gun-free zones based on safety concerns. Funding: This work was funded in part by the National Collaborative on Gun Violence Research and the Arnold Foundation.

13.
Geroscience ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39098984

RESUMEN

Visit-to-visit blood pressure variability (BPV) predicts age-related hippocampal atrophy, neurodegeneration, and memory decline in older adults. Beat-to-beat BPV may represent a more reliable and efficient tool for prospective risk assessment, but it is unknown whether beat-to-beat BPV is similarly associated with hippocampal neurodegeneration, or with plasma markers of neuroaxonal/neuroglial injury. Independently living older adults without a history of dementia, stroke, or other major neurological disorders were recruited from the community (N = 104; age = 69.5 ± 6.7 (range 55-89); 63% female). Participants underwent continuous blood pressure monitoring, brain MRI, venipuncture, and cognitive testing over two visits. Hippocampal volumes, plasma neurofilament light, and glial fibrillary acidic protein levels were assessed. Beat-to-beat BPV was quantified as systolic blood pressure average real variability during 7-min of supine continuous blood pressure monitoring. The cross-sectional relationship between beat-to-beat BPV and hippocampal volumes, cognitive domain measures, and plasma biomarkers was assessed using multiple linear regression with adjustment for demographic covariates, vascular risk factors, and average systolic blood pressure. Elevated beat-to-beat BPV was associated with decreased left hippocampal volume (P = .008), increased plasma concentration of glial fibrillary acidic protein (P = .006), and decreased memory composite score (P = .02), independent of age, sex, average systolic blood pressure, total intracranial volume, and vascular risk factor burden. In summary, beat-to-beat BPV is independently associated with decreased left hippocampal volume, increased neuroglial injury, and worse memory ability. Findings are consistent with prior studies examining visit-to-visit BPV and suggest beat-to-beat BPV may be a useful marker of hemodynamic brain injury in older adults.

14.
NPJ Metab Health Dis ; 2(1): 19, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39100919

RESUMEN

Metabolic dysfunction-associated steatotic liver disease (MASLD) originates from a homeostatic imbalance in hepatic lipid metabolism. Increased fat deposition in the liver of people suffering from MASLD predisposes them to develop further metabolic derangements, including diabetes mellitus, metabolic dysfunction-associated steatohepatitis (MASH), and other end-stage liver diseases. Unfortunately, only limited pharmacological therapies exist for MASLD to date. Autophagy, a cellular catabolic process, has emerged as a primary mechanism of lipid metabolism in mammalian hepatocytes. Furthermore, preclinical studies with autophagy modulators have shown promising results in resolving MASLD and mitigating its progress into deleterious liver pathologies. In this review, we discuss our current understanding of autophagy-mediated hepatic lipid metabolism, its therapeutic modulation for MASLD treatment, and current limitations and scope for clinical translation.

15.
J Am Chem Soc ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39106078

RESUMEN

Pyridoxal-5'-phosphate (PLP) and derivatives of this cofactor enable a plethora of reactions in both enzyme-mediated and free-in-solution transformations. With few exceptions in each category, such chemistry has predominantly involved two-electron processes. This sometimes poses a significant challenge for using PLP to build tetrasubstituted carbon centers, especially when the reaction is reversible. The ability to access radical pathways is paramount to broadening the scope of reactions catalyzed by this coenzyme. In this study, we demonstrate the ability to access a radical PLP-based intermediate and engage this radical intermediate in a number of C-C bond-forming reactions. By selection of an appropriate oxidant, single-electron oxidation of the quinonoid intermediate can be achieved, which can subsequently be applied to C-C bond-forming reactions. Through this radical reaction pathway, we synthesized a series of α-tertiary amino acids and esters to investigate the substrate scope and identify nonproductive reaction pathways. Beyond the amino acid model system, we demonstrate that other classes of amine substrates can be applied in this reaction and that a range of small molecule reagents can serve as coupling partners to the semiquinone radical. We anticipate that this versatile semiquinone radical species will be central to the development of a range of novel reactions.

16.
Sci Rep ; 14(1): 17853, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090217

RESUMEN

Acute respiratory distress syndrome (ARDS) is a devastating critical care syndrome with significant morbidity and mortality. The objective of this study was to evaluate the predictive values of dynamic clinical indices by developing machine-learning (ML) models for early and accurate clinical assessment of the disease prognosis of ARDS. We conducted a retrospective observational study by applying dynamic clinical data collected in the ARDSNet FACTT Trial (n = 1000) to ML-based algorithms for predicting mortality. In order to compare the significance of clinical features dynamically, we further applied the random forest (RF) model to nine selected clinical parameters acquired at baseline and day 3 independently. An RF model trained using clinical data collected at day 3 showed improved performance and prognostication efficacy (area under the curve [AUC]: 0.84, 95% CI: 0.78-0.89) compared to baseline with an AUC value of 0.72 (95% CI: 0.65-0.78). Mean airway pressure (MAP), bicarbonate, age, platelet count, albumin, heart rate, and glucose were the most significant clinical indicators associated with mortality at day 3. Thus, clinical features collected early (day 3) improved performance of integrative ML models with better prognostication for mortality. Among these, MAP represented the most important feature for ARDS patients' early risk stratification.


Asunto(s)
Aprendizaje Automático , Síndrome de Dificultad Respiratoria , Humanos , Síndrome de Dificultad Respiratoria/mortalidad , Síndrome de Dificultad Respiratoria/diagnóstico , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Pronóstico , Anciano , Algoritmos , Adulto , Valor Predictivo de las Pruebas , Curva ROC
17.
Space Sci Rev ; 220(5): 51, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38948073

RESUMEN

The Radar for Europa Assessment and Sounding: Ocean to Near-surface (REASON) is a dual-frequency ice-penetrating radar (9 and 60 MHz) onboard the Europa Clipper mission. REASON is designed to probe Europa from exosphere to subsurface ocean, contributing the third dimension to observations of this enigmatic world. The hypotheses REASON will test are that (1) the ice shell of Europa hosts liquid water, (2) the ice shell overlies an ocean and is subject to tidal flexing, and (3) the exosphere, near-surface, ice shell, and ocean participate in material exchange essential to the habitability of this moon. REASON will investigate processes governing this material exchange by characterizing the distribution of putative non-ice material (e.g., brines, salts) in the subsurface, searching for an ice-ocean interface, characterizing the ice shell's global structure, and constraining the amplitude of Europa's radial tidal deformations. REASON will accomplish these science objectives using a combination of radar measurement techniques including altimetry, reflectometry, sounding, interferometry, plasma characterization, and ranging. Building on a rich heritage from Earth, the moon, and Mars, REASON will be the first ice-penetrating radar to explore the outer solar system. Because these radars are untested for the icy worlds in the outer solar system, a novel approach to measurement quality assessment was developed to represent uncertainties in key properties of Europa that affect REASON performance and ensure robustness across a range of plausible parameters suggested for the icy moon. REASON will shed light on a never-before-seen dimension of Europa and - in concert with other instruments on Europa Clipper - help to investigate whether Europa is a habitable world.

18.
JPRAS Open ; 41: 61-74, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38948075

RESUMEN

Flap necrosis continues to occur in skin free flap autologous breast reconstruction. Therefore, we investigated the benefits of indocyanine green angiography (ICGA) using quantitative parameters for the objective, perioperative evaluation of flap perfusion. In addition, we investigated the feasibility of hyperspectral (HSI) and thermal imaging (TI) for postoperative flap monitoring. A single-center, prospective observational study was performed on 15 patients who underwent deep inferior epigastric perforator (DIEP) flap breast reconstruction (n=21). DIEP-flap perfusion was evaluated using ICGA, HSI, and TI using a standardized imaging protocol. The ICGA perfusion curves and derived parameters, HSI extracted oxyhemoglobin (oxyHb) and deoxyhemoglobin (deoxyHb) values, and flap temperatures from TI were analyzed and correlated to the clinical outcomes. Post-hoc quantitative analysis of intraoperatively collected data of ICGA application accurately distinguished between adequately and insufficiently perfused DIEP flaps. ICG perfusion curves identified the lack of arterial inflow (n=2) and occlusion of the venous outflow (n=1). In addition, a postoperatively detected partial flap epidermolysis could have been predicted based on intraoperative quantitative ICGA data. During postoperative monitoring, HSI was used to identify impaired perfusion areas within the DIEP flap based on deoxyHb levels. The results of this study showed a limited added value of TI. Quantitative, post-hoc analysis of ICGA data produced objective and reproducible parameters that enabled the intraoperative detection of arterial and venous congested DIEP flaps. HSI appeared to be a promising technique for postoperative flap perfusion assessment. A diagnostic accuracy study is needed to investigate ICGA and HSI parameters in real-time and demonstrate their clinical benefit.

19.
Neuroradiology ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963424

RESUMEN

BACKGROUND AND PURPOSE: Traumatic brain injury (TBI) is a major source of health loss and disability worldwide. Accurate and timely diagnosis of TBI is critical for appropriate treatment and management of the condition. Neuroimaging plays a crucial role in the diagnosis and characterization of TBI. Computed tomography (CT) is the first-line diagnostic imaging modality typically utilized in patients with suspected acute mild, moderate and severe TBI. Radiology reports play a crucial role in the diagnostic process, providing critical information about the location and extent of brain injury, as well as factors that could prevent secondary injury. However, the complexity and variability of radiology reports can make it challenging for healthcare providers to extract the necessary information for diagnosis and treatment planning. METHODS/RESULTS/CONCLUSION: In this article, we report the efforts of an international group of TBI imaging experts to develop a clinical radiology report template for CT scans obtained in patients suspected of TBI and consisting of fourteen different subdivisions (CT technique, mechanism of injury or clinical history, presence of scalp injuries, fractures, potential vascular injuries, potential injuries involving the extra-axial spaces, brain parenchymal injuries, potential injuries involving the cerebrospinal fluid spaces and the ventricular system, mass effect, secondary injuries, prior or coexisting pathology).

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