Background
The shortage of donor organs for transplantation remains a worldwide problem. The utilization of suboptimal deceased donors enlarges the pool of potential organs, yet consequently, ...clinicians face the difficult decision of whether these sub‐optimal organs are of sufficient quality for transplantation. Novel technologies could play a pivotal role in making pre‐transplant organ assessment more objective and reliable.
Methods
Ex vivo normothermic machine perfusion (NMP) at temperatures around 35–37°C allows organ quality assessment in a near‐physiological environment. Advanced magnetic resonance imaging (MRI) techniques convey unique information about an organ's structural and functional integrity. The concept of applying magnetic resonance imaging during renal normothermic machine perfusion is novel in both renal and radiological research and we have developed the first MRI‐compatible NMP setup for human‐sized kidneys.
Results
We were able to obtain a detailed and real‐time view of ongoing processes inside renal grafts during ex vivo perfusion. This new technique can visualize structural abnormalities, quantify regional flow distribution, renal metabolism, and local oxygen availability, and track the distribution of ex vivo administered cellular therapy.
Conclusion
This platform allows for advanced pre‐transplant organ assessment, provides a new realistic tool for studies into renal physiology and metabolism, and may facilitate therapeutic tracing of pharmacological and cellular interventions to an isolated kidney.
Various lines of evidence accumulated over the past 30 years indicate that the cerebellum, long recognized as essential for motor control, also has considerable influence on perceptual processes. In ...this paper, we bring together experts from psychology and neuroscience, with the aim of providing a succinct but comprehensive overview of key findings related to the involvement of the cerebellum in sensory perception. The contributions cover such topics as anatomical and functional connectivity, evolutionary and comparative perspectives, visual and auditory processing, biological motion perception, nociception, self-motion, timing, predictive processing, and perceptual sequencing. While no single explanation has yet emerged concerning the role of the cerebellum in perceptual processes, this consensus paper summarizes the impressive empirical evidence on this problem and highlights diversities as well as commonalities between existing hypotheses. In addition to work with healthy individuals and patients with cerebellar disorders, it is also apparent that several neurological conditions in which perceptual disturbances occur, including autism and schizophrenia, are associated with cerebellar pathology. A better understanding of the involvement of the cerebellum in perceptual processes will thus likely be important for identifying and treating perceptual deficits that may at present go unnoticed and untreated. This paper provides a useful framework for further debate and empirical investigations into the influence of the cerebellum on sensory perception.
We found that the macaque inferior parietal (PFG and anterior intraparietal AIP), ventral premotor (F5p and F5a), and ventrolateral prefrontal (rostral 46vc and intermediate 12r) areas forming a ...network involved in controlling purposeful hand actions ("lateral grasping network") are a source of corticotectal projections. Based on injections of anterograde tracers at the cortical level, the results showed that all these areas displayed relatively dense projections to the intermediate and deep gray layers of the ipsilateral superior colliculus (SC) and to the ventrally adjacent mesencephalic reticular formation. In the SC, the labeling tended to be richer in the lateral part along almost the entire rostro-caudal extent, that is, in regions controlling microsaccades and downward gaze shifts and hosting arm-related neurons and neurons modulated by the contact of the hand with the target. These projections could represent a descending motor pathway for controlling proximo-distal arm synergies. Furthermore, they could broadcast to the SC information related to hand action goals and object affordances extraction and selection. This information could be used in the SC for controlling orienting behavior (gaze and reaching movements) to the targets of object-oriented actions and for the eye-hand coordination necessary for appropriate hand-object interactions.
Summary
Acceptance criteria of deceased donor organs have gradually been extended toward suboptimal quality, posing an urgent need for more objective pre‐transplant organ assessment. Ex vivo ...normothermic machine perfusion (NMP) combined with magnetic resonance imaging (MRI) could assist clinicians in deciding whether a donor kidney is suitable for transplantation. Aim of this study was to characterize the regional distribution of perfusate flow during NMP, to better understand how ex vivo kidney assessment protocols should eventually be designed. Nine porcine and 4 human discarded kidneys underwent 3 h of NMP in an MRI‐compatible perfusion setup. Arterial spin labeling scans were performed every 15 min, resulting in perfusion‐weighted images that visualize intrarenal flow distribution. At the start of NMP, all kidneys were mainly centrally perfused and it took time for the outer cortex to reach its physiological dominant perfusion state. Calculated corticomedullary ratios based on the perfusion maps reached a physiological range comparable to in vivo observations, but only after 1 to 2 h after the start of NMP. Before that, the functionally important renal cortex appeared severely underperfused. Our findings suggest that early functional NMP quality assessment markers may not reflect actual physiology and should therefore be interpreted with caution.
This study is the first to visualize the regional distribution of renal perfusate flow with magnetic resonance techniques during the first hours of warm ex vivo perfusion in porcine and human kidneys.
We report on the modification of tin (Sn) film surfaces under a laser beam irradiation that triggers surface plasmon polariton (SPP) excitations. The observed surface features in the form of small ...raised grains, with well-defined rooting, look similar to tin whisker nodules. We attribute the appearance of those features to the field-induced nucleation caused by the SPP related strong electric field. Possible implications of our findings include accelerated-life testing for tin whisker growth related reliability as well as applications to nanoparticle nucleation.
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Objectives
Assessment of thoracic aortic dimensions with non-ECG-triggered contrast-enhanced magnetic resonance angiography (CE-MRA) is accompanied with motion artefacts and requires gadolinium. To ...avoid both motion artefacts and gadolinium administration, we evaluated the similarity and reproducibility of dimensions measured on ECG-triggered, balanced steady-state free precession (SSFP) MRA as alternative to CE-MRA.
Methods
All patients, with varying medical conditions, referred for thoracic aortic examination between September 2016 and March 2018, who underwent non-ECG-triggered CE-MRA and SSFP-MRA (1.5 T) were retrospectively included (
n
= 30). Aortic dimensions were measured after double-oblique multiplanar reconstruction by two observers at nine landmarks predefined by literature guidelines. Image quality was scored at the sinus of Valsalva, mid-ascending aorta and mid-descending aorta by semi-automatically assessing the vessel sharpness.
Results
Aortic dimensions showed high agreement between non-ECG-triggered CE-MRA and SSFP-MRA (
r
= 0.99,
p
< 0.05) without overestimation or underestimation of aortic dimensions in SSFP-MRA (mean difference, 0.1 mm; limits of agreement, − 1.9 mm and 1.9 mm). Intra- and inter-observer variabilities were significantly smaller with SSFP-MRA for the sinus of Valsalva and sinotubular junction. Image quality of the sinus of Valsalva was significantly better with SSFP-MRA, as fewer images were of impaired quality (3/30) than in CE-MRA (21/30). Reproducibility of dimensions was significantly better in images scored as good quality compared to impaired quality in both sequences.
Conclusions
Thoracic aortic dimensions measured on SSFP-MRA and non-ECG-triggered CE-MRA were similar. As expected, SSFP-MRA showed better reproducibility close to the aortic root because of lesser motion artefacts, making it a feasible non-contrast imaging alternative.
Key Points
•
SSFP-MRA provides similar dimensions as non-ECG-triggered CE-MRA.
•
Intra- and inter-observer reproducibilities improve for the sinus of Valsalva and sinotubular junction with SSFP-MRA.
•
ECG-triggered SSFP-MRA shows better image quality for landmarks close to the aortic root in the absence of cardiac motion.
Persistent molecules, such as pesticides, herbicides, and pharmaceuticals, pose significant threats to both the environment and human health. Advancements in developing efficient photocatalysts for ...degrading these substances can play a fundamental role in remediating contaminated environments, thereby enhancing safety for all forms of life. This study investigates the enhancement of photocatalytic efficiency achieved by incorporating La3+ into Ag3PO4, using the co-precipitation method in an aqueous medium. These materials were utilized in the photocatalytic degradation of Rhodamine B (RhB) and Ciprofloxacin (CIP) under visible light irradiation, with monitoring conducted through high-performance liquid chromatography (HPLC). The synthesized materials exhibited improved stability and photodegradation levels for RhB. Particularly noteworthy was the 2% La3+-incorporated sample (APL2), which achieved a 32.6% mineralization of CIP, nearly three times higher than pure Ag3PO4. Toxicological analysis of the residue from CIP photodegradation using the microalga Raphidocelis subcapitata revealed high toxicity due to the leaching of Ag + ions from the catalyst. This underscores the necessity for cautious wastewater disposal after using the photocatalyst. The toxicity of the APL2 photocatalysts was thoroughly assessed through comprehensive toxicological tests involving embryo development in Danio rerio, revealing its potential to induce death and malformations in zebrafish embryos, even at low concentrations. This emphasizes the importance of meticulous management. Essentially, this study adeptly delineated a thorough toxicological profile intricately intertwined with the photocatalytic efficacy of newly developed catalysts and the resultant waste produced, prompting deliberations on the disposal of degraded materials post-exposure to photocatalysts.
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•Doping significantly enhances the photocatalytic performance of Ag3PO4.•This study explores potent photocatalyst for wastewater treatment.•Ecotoxicity tests help optimize its use in real water disposal systems.•Photocatalyst residue differs ecologically from degraded pharmaceutical residue.
Coronavirus disease 2019 (COVID-19) has had a substantial impact on the incidence of cardiac arrest and survival. The challenge is to find the correct balance between the risk to the rescuer when ...undertaking cardiopulmonary resuscitation (CPR) on a person with possible COVID-19 and the risk to that person if CPR is delayed. These guidelines focus specifically on patients with suspected or confirmed COVID-19. The guidelines include the delivery of basic and advanced life support in adults and children and recommendations for delivering training during the pandemic. Where uncertainty exists treatment should be informed by a dynamic risk assessment which may consider current COVID-19 prevalence, the person’s presentation (e.g. history of COVID-19 contact, COVID-19 symptoms), likelihood that treatment will be effective, availability of personal protective equipment (PPE) and personal risks for those providing treatment. These guidelines will be subject to evolving knowledge and experience of COVID-19. As countries are at different stages of the pandemic, there may some international variation in practice.
We traced the cortical connections of the 4 cytoarchitectonic fields—Opt, PG, PFG, PF—forming the cortical convexity of the macaque inferior parietal lobule (IPL). Each of these fields displayed ...markedly distinct sets of connections. Although Opt and PG are both targets of dorsal visual stream and temporal visual areas, PG is also target of somatosensory and auditory areas. Primary parietal and frontal connections of Opt include area PGm and eye-related areas. In contrast, major parietal and frontal connections of PG include IPL, caudal superior parietal lobule (SPL), and agranular frontal arm-related areas. PFG is target of somatosensory areas and also of the medial superior temporal area (MST) and temporal visual areas and is connected with IPL, rostral SPL, and ventral premotor arm- and face-related areas. Finally, PF is primarily connected with somatosensory areas and with parietal and frontal face- and arm-related areas. The present data challenge the bipartite subdivision of the IPL convexity into a caudal and a rostral area (7a and 7b, respectively) and provide a new anatomical frame of reference of the macaque IPL convexity that advances our present knowledge on the functional organization of this cortical sector, giving new insight into its possible role in space perception and motor control.
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