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2.
Sci Rep ; 13(1): 22822, 2023 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-38129558

RESUMEN

Quantitative muscle MRI is increasingly important in the non-invasive evaluation of neuromuscular disorders and their progression. Underlying histopathotological alterations, leading to changes in qMRI parameters are incompletely unraveled. Early microstructural differences of unknown origin reflected by Diffusion MRI in non-fat infiltrated muscles were detected in Pompe patients. This study employed a longitudinal approach with a Pompe disease mouse model to investigate the histopathological basis of these changes. Monthly scans of Pompe (Gaa6neo/6neo) and wildtype mice (age 1-8 months) were conducted using diffusion MRI, T2-mapping, and Dixon-based water-fat imaging on a 7 T scanner. Immunofluorescence studies on quadriceps muscles were analyzed for lysosomal accumulations and autophagic buildup and correlated with MRI outcome measures. Fat fraction and water-T2 did not differ between groups and remained stable over time. In Pompe mice, fractional anisotropy increased, while mean diffusivity (MD) and radial diffusivity (RD) decreased in all observed muscles. Autophagic marker and muscle fibre diameter revealed significant negative correlations with reduced RD and MD, while lysosomal marker did not show any change or correlation. Using qMRI, we showed diffusion changes in muscles of presymptomatic Pompe mice without fat-infiltrated muscles and correlated them to autophagic markers and fibre diameter, indicating diffusion MRI reveals autophagic buildup.


Asunto(s)
Enfermedad del Almacenamiento de Glucógeno Tipo II , Humanos , Ratones , Animales , Lactante , Enfermedad del Almacenamiento de Glucógeno Tipo II/diagnóstico por imagen , Enfermedad del Almacenamiento de Glucógeno Tipo II/patología , Fibras Musculares Esqueléticas/patología , Imagen de Difusión por Resonancia Magnética , Músculo Cuádriceps , Modelos Animales de Enfermedad , Agua
3.
Sci Rep ; 13(1): 16405, 2023 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-37828055

RESUMEN

During the Upper Paleolithic, lions become an important theme in Paleolithic art and are more frequent in anthropogenic faunal assemblages. However, the relationship between hominins and lions in earlier periods is poorly known and primarily interpreted as interspecies competition. Here we present new evidence for Neanderthal-cave lion interactions during the Middle Paleolithic. We report new evidence of hunting lesions on the 48,000 old cave lion skeleton found at Siegsdorf (Germany) that attest to the earliest direct instance of a large predator kill in human history. A comparative analysis of a partial puncture to a rib suggests that the fatal stab was delivered with a wooden thrusting spear. We also present the discovery of distal lion phalanges at least 190,000 old from Einhornhöhle (Germany), representing the earliest example of the use of cave lion skin by Neanderthals in Central Europe. Our study provides novel evidence on a new dimension of Neanderthal behavioral complexity.


Asunto(s)
Hominidae , Leones , Hombre de Neandertal , Panthera , Animales , Humanos , Caza , Arqueología , Fósiles
4.
Nat Ecol Evol ; 5(9): 1273-1282, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34226702

RESUMEN

While there is substantial evidence for art and symbolic behaviour in early Homo sapiens across Africa and Eurasia, similar evidence connected to Neanderthals is sparse and often contested in scientific debates. Each new discovery is thus crucial for our understanding of Neanderthals' cognitive capacity. Here we report on the discovery of an at least 51,000-year-old engraved giant deer phalanx found at the former cave entrance of Einhornhöhle, northern Germany. The find comes from an apparent Middle Palaeolithic context that is linked to Neanderthals. The engraved bone demonstrates that conceptual imagination, as a prerequisite to compose individual lines into a coherent design, was present in Neanderthals. Therefore, Neanderthal's awareness of symbolic meaning is very likely. Our findings show that Neanderthals were capable of creating symbolic expressions before H. sapiens arrived in Central Europe.


Asunto(s)
Ciervos , Hombre de Neandertal , Animales , Huesos , Cuevas , Europa (Continente) , Humanos , Recién Nacido
6.
Front Neurosci ; 15: 805679, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34992520

RESUMEN

Functional magnetic resonance imaging, as a non-invasive technique, offers unique opportunities to assess brain function and connectivity under a broad range of applications, ranging from passive sensory stimulation to high-level cognitive abilities, in awake animals. This approach is confounded, however, by the fact that physical restraint and loud unpredictable acoustic noise must inevitably accompany fMRI recordings. These factors induce marked stress in rodents, and stress-related elevations of corticosterone levels are known to alter information processing and cognition in the rodent. Here, we propose a habituation strategy that spans specific stages of adaptation to restraint, MRI noise, and confinement stress in awake rats and circumvents the need for surgical head restraint. This habituation protocol results in stress levels during awake fMRI that do not differ from pre-handling levels and enables stable image acquisition with very low motion artifacts. For this, rats were gradually trained over a period of three weeks and eighteen training sessions. Stress levels were assessed by analysis of fecal corticosterone metabolite levels and breathing rates. We observed significant drops in stress levels to below pre-handling levels at the end of the habituation procedure. During fMRI in awake rats, after the conclusion of habituation and using a non-invasive head-fixation device, breathing was stable and head motion artifacts were minimal. A task-based fMRI experiment, using acoustic stimulation, conducted 2 days after the end of habituation, resulted in precise whole brain mapping of BOLD signals in the brain, with clear delineation of the expected auditory-related structures. The active discrimination by the animals of the acoustic stimuli from the backdrop of scanner noise was corroborated by significant increases in BOLD signals in the thalamus and reticular formation. Taken together, these data show that effective habituation to awake fMRI can be achieved by gradual and incremental acclimatization to the experimental conditions. Subsequent BOLD recordings, even during superimposed acoustic stimulation, reflect low stress-levels, low motion and a corresponding high-quality image acquisition. Furthermore, BOLD signals obtained during fMRI indicate that effective habituation facilitates selective attention to sensory stimuli that can in turn support the discrimination of cognitive processes in the absence of stress confounds.

7.
Aerosp Med Hum Perform ; 92(1): 11-19, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33357267

RESUMEN

INTRODUCTION: The visual scanning techniques used by helicopter pilots are a critical skill to accomplish safe and correct landing. According to the human information processing theory, visual scanning techniques can be analyzed as a function of fixation location, number, and duration of fixations.METHODS: This study assessed these techniques in expert and novice pilots during an open sea flight simulation in a low-workload condition, consisting of a daylight and good weather simulation, and in a high-workload condition of night-time, low visibility, and adverse weather conditions. Taking part in the study were 12 helicopter pilots. Mental workload was assessed through psychological measures (NASA-TLX). The pilots performance was assessed and eye movements were recorded using an eye-tracker during four phases of the flight simulations.RESULTS: Overall, pilots made more fixations out of the window (OTW; 22.54) than inside the cockpit (ITC; 11.08), Fixations were longer OTW (830.17 ms) than ITC (647.97 ms) and they were shorter in the low-demand condition (626.27 ms). Further, pilots reported higher mental workload (NASA-TLX) in the high-demand condition compared to the low-demand condition, regardless of their expertise, and expert pilots reported a lower mental workload compared to novice pilots.DISCUSSION: Pilots performance and perceived mental workload varied as a function of expertise and flight conditions. Pilots rely on instrument support during the cruise phase and external visual cues during the landing phase. The implications for a new visual landing system design are discussed.Rainieri G, Fraboni F, Russo G, Tul M, Pingitore A, Tessari A, Pietrantoni L. Visual scanning techniques and mental workload of helicopter pilots during simulated flight. Aerosp Med Hum Perform. 2021; 92(1):1119.


Asunto(s)
Pilotos , Aeronaves , Señales (Psicología) , Movimientos Oculares , Humanos , Análisis y Desempeño de Tareas , Carga de Trabajo
8.
Sci Data ; 7(1): 364, 2020 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-33097734

RESUMEN

In the Paleolithic, geometric signs are abundant. They appear in rock art as well as on mobile objects like artworks, tools, or personal ornaments. These signs are often interpreted as a reflection of symbolic thought and associated with the origin of cognitively modern behavior. SignBase is a project collecting the wealth of geometric signs on mobile objects in the European Upper Paleolithic, African Middle Stone Age (MSA), as well as selected sites from the Near East and South East Asia. Currently, more than 500 objects of the Aurignacian techno-complex (ca. 43,000 to 30,000 years BP) are registered in SignBase. They are linked to information about geographic and archaeological provenience, the type of object and material, size and preservation, and respective literature references. We identify around 30 different sign types found on these objects across Europe in the Aurignacian and illustrate how SignBase can be used to analyze geographical clusters. Ultimately, we aim to enable quantitative analyses of abstract graphical expression before the emergence of writing.

9.
J Sports Sci ; 33(10): 1019-27, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25385452

RESUMEN

When two athletes meet inside the ropes of the boxing ring to fight, their cognitive systems have to respond as quickly as possible to a manifold of stimuli to assure victory. In the present work, we studied the pre-attentive mechanisms, which form the basis of an athlete's ability in reacting to an opponent's punches. Expert boxers, beginner boxers and people with no experience of boxing performed a Simon-like task where they judged the colour of the boxing gloves worn by athletes in attack postures by pressing two lateralised keys. Although participants were not instructed to pay attention to the direction of the punches, beginner boxers' responses resembled a defence-related pattern, expert boxers' resembled counterattacks, whereas non-athletes' responses were not influenced by the unrelated task information. Results are discussed in the light of an expertise-related action simulation account.


Asunto(s)
Anticipación Psicológica , Boxeo/psicología , Adolescente , Adulto , Atención , Humanos , Masculino , Tiempo de Reacción , Análisis y Desempeño de Tareas , Adulto Joven
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