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1.
J Appl Psychol ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39133603

RESUMEN

Numerous faking warning types have been investigated as interventions that aim to minimize applicant faking in preemployment personality tests. However, studies vary in the types and effectiveness of faking warnings used, personality traits, as well as the use of different recruitment settings and participant samples. In the present study, we advance a theory that classifies faking warning types based on ability, opportunity, and motivation to fake (Tett & Simonet, 2011), which we validated using subject matter expert ratings. Using this framework as a guide, we conducted a random-effects pairwise meta-analysis (k = 34) and a network meta-analysis (k = 36). We used inverse-variance weighting to pool the effect sizes and relied on 80% prediction intervals to evaluate heterogeneity. Overall, faking warnings had a significant, moderate effect in reducing applicant faking (d = 0.31, 95% CI [0.23, 0.39]). Warning types that theoretically targeted ability, motivation, and opportunity to fake (d = 0.36, 95% CI [0.25, 0.47]) were the most effective. Additionally, warnings were least effective in studies using recruitment settings and nonuniversity student samples. However, all effect sizes contained substantial heterogeneity, and all warning types will be ineffective in some contexts. Organizations should be cognizant that warnings alone may not be sufficient to address applicant faking, and future research should explore how their effectiveness varies depending on other contextual factors and applicant characteristics. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

2.
bioRxiv ; 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39026699

RESUMEN

Broadly neutralizing antibodies (bNAbs) have shown great promise for prevention and treatment of HIV infection. Breadth of bNAb neutralization, measured in vitro across panels of diverse viral isolates, is often used as a predictor of clinical potential. However, recent prevention studies demonstrate that the clinical efficacy of a broad and potent bNAb (VRC01) is undermined by neutralization resistance of circulating strains. Using HIV-infected humanized mice, we find that therapeutic efficacy of bNAbs delivered as Vectored ImmunoTherapy (VIT) is a function of both the fitness cost and resistance benefit of mutations that emerge during viral escape, which we term 'escapability'. Applying this mechanistic framework, we find that the sequence of the envelope V5-loop alters the resistance benefits of mutants that arise during escape, thereby impacting the therapeutic efficacy of VIT-mediated viral suppression. We also find that an emtricitabine-based antiretroviral drug regimen dramatically enhances the efficacy of VIT, by reducing the fitness of mutants along the escape path. Our findings demonstrate that bNAb escapability is a key determinant to consider in the rational design of antibody regimens with maximal efficacy and illustrates a tractable means of minimizing viral escape from existing bNAbs.

3.
bioRxiv ; 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38854135

RESUMEN

By combining an external display operating at 360 frames per second with an Adaptive Optics Scanning Laser Ophthalmoscope (AOSLO) for human foveal imaging, we demonstrate color stimulus delivery at high spatial and temporal resolution in AOSLO psychophysics experiments. A custom pupil relay enables viewing of the stimulus through a 3-mm effective pupil diameter and provides refractive error correction from -8 to +4 diopters. Performance of the assembled and aligned pupil relay was validated by measuring the wavefront error across the field of view and correction range, and the as-built Strehl ratio was 0.64 or better. High-acuity stimuli were rendered on the external display and imaged through the pupil relay to demonstrate that spatial frequencies up to 54 cycles per degree, corresponding to 20/11 visual acuity, are resolved. The completed external display was then used to render fixation markers across the field of view of the monitor, and a continuous retinal montage spanning 9.4 by 5.4 degrees of visual angle was acquired with the AOSLO. We conducted eye-tracking experiments during free-viewing and high-acuity tasks with polychromatic images presented on the external display. Sub-arcminute eye position uncertainty was achieved, enabling precise localization of the line of sight on the monitor while simultaneously imaging the fine structure of the human central fovea. This high refresh rate display overcomes the temporal, spectral, and field of view limitations of AOSLO-based stimulus presentation, enabling natural monocular viewing of stimuli in psychophysics experiments conducted with AOSLO.

4.
Appl Opt ; 63(3): 730-742, 2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38294386

RESUMEN

In prior art, advances in adaptive optics scanning laser ophthalmoscope (AOSLO) technology have enabled cones in the human fovea to be resolved in healthy eyes with normal vision and low to moderate refractive errors, providing new insight into human foveal anatomy, visual perception, and retinal degenerative diseases. These high-resolution ophthalmoscopes require careful alignment of each optical subsystem to ensure diffraction-limited imaging performance, which is necessary for resolving the smallest foveal cones. This paper presents a systematic and rigorous methodology for building, aligning, calibrating, and testing an AOSLO designed for imaging the cone mosaic of the central fovea in humans with cellular resolution. This methodology uses a two-stage alignment procedure and thorough system testing to achieve diffraction-limited performance. Results from retinal imaging of healthy human subjects under 30 years of age with refractive errors of less than 3.5 diopters using either 680 nm or 840 nm light show that the system can resolve cones at the very center of the fovea, the region where the cones are smallest and most densely packed.


Asunto(s)
Fóvea Central , Oftalmoscopios , Enfermedades de la Retina , Humanos , Calibración , Fóvea Central/diagnóstico por imagen , Rayos Láser , Errores de Refracción , Enfermedades de la Retina/diagnóstico por imagen
5.
J Vis ; 23(11): 42, 2023 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-37733536

RESUMEN

Studies of emmetropization have traditionally focused on the spatial characteristics of visual input signals. Yet the input to the retina is not a two-dimensional pattern but a temporally-varying luminance flow. The temporal structure of this flow is predominately determined by eye movements, as the human eyes move incessantly. Even when fixating on a single point, a persistent motion known as ocular drift reformats the luminance flow in a way that counterbalances the spectra of natural scenes. It is established that emmetropes are highly sensitive to these luminance modulations. However, their visual consequences in myopia and hyperopia are unknown. Here, we first review how the temporal-frequency distribution of retinal input signals varies with the amount of ocular drift. We then use a detailed optical/geometrical model of the eye to study how the eye movements jointly shape retinal input as a function of refraction. We show that, within the temporal range of sensitivity of the retina, the spatial frequency distribution of the input signals conveys signed information about defocus. Specifically, for a given degree of defocus, myopic retinas experience more power from low spatial frequency stimuli than hyperopic retinas. These redistribution of input power may have a consequence during eye growth supporting the proposal that eye movements should be taken into consideration in the process of emmetropization.


Asunto(s)
Hiperopía , Miopía , Humanos , Movimientos Oculares , Retina , Cara
6.
BMC Ecol Evol ; 23(1): 44, 2023 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-37648992

RESUMEN

Neck elongation has appeared independently in several tetrapod groups, including giraffes and sauropod dinosaurs on land, birds and pterosaurs in the air, and sauropterygians (plesiosaurs and relatives) in the oceans. Long necks arose in Early Triassic sauropterygians, but the nature and rate of that elongation has not been documented. Here, we report a new species of pachypleurosaurid sauropterygian, Chusaurus xiangensis gen. et sp. nov., based on two new specimens from the Early Triassic Nanzhang-Yuan'an Fauna in the South China Block. The new species shows key features of its Middle Triassic relatives, but has a relatively short neck, measuring 0.48 of the trunk length, compared to > 0.8 from the Middle Triassic onwards. Comparative phylogenetic analysis shows that neck elongation occurred rapidly in all Triassic eosauropterygian lineages, probably driven by feeding pressure in a time of rapid re-establishment of new kinds of marine ecosystems.


Asunto(s)
Dinosaurios , Animales , China , Ecosistema , Jirafas , Filogenia , Reptiles
7.
Palaeontology ; 65(4): e12615, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36248238

RESUMEN

Microfossils have a ubiquitous and well-studied fossil record with temporally and spatially fluctuating diversity, but how this arises and how major events affect speciation and extinction is uncertain. We present one of the first applications of PyRate to a micropalaeontological global occurrence dataset, reconstructing diversification rates within a Bayesian framework from the Mesozoic to the Neogene in four microfossil groups: planktic foraminiferans, calcareous nannofossils, radiolarians and diatoms. Calcareous and siliceous groups demonstrate opposed but inconsistent responses in diversification. Radiolarian origination increases from c. 104 Ma, maintaining high rates into the Cenozoic. Calcareous microfossil diversification rates significantly declines across the Cretaceous-Palaeogene boundary, while rates in siliceous microfossil groups remain stable until the Paleocene-Eocene transition. Diversification rates in the Cenozoic are largely stable in calcareous groups, whereas the Palaeogene is a turbulent time for diatoms. Diversification fluctuations are driven by climate change and fluctuations in sea surface temperatures, leading to different responses in the groups generating calcareous or siliceous microfossils. Extinctions are apparently induced by changes in anoxia, acidification and stratification; speciation tends to be associated with upwelling, productivity and ocean circulation. These results invite further micropalaeontological quantitative analysis and study of the effects of major transitions in the fossil record. Despite extensive occurrence data, regional diversification events were not recovered; neither were some global events. These unexpected results show the need to consider multiple spatiotemporal levels of diversity and diversification analyses and imply that occurrence datasets of different clades may be more appropriate for testing some hypotheses than others.

8.
J Anat ; 241(6): 1409-1423, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36175086

RESUMEN

Jurassic ichthyosaurs dominated upper trophic levels of marine ecosystems. Many species coexisted alongside each another, and it is uncertain whether they competed for the same array of food or divided dietary resources, each specializing in different kinds of prey. Here, we test whether feeding differences existed between species, applying finite element analysis to ichthyosaurs for the first time. We examine two juvenile ichthyosaur specimens, referred to Hauffiopteryx typicus and Stenopterygius triscissus, from the Strawberry Bank Lagerstätte, a shallow marine environment from the Early Jurassic of southern England (Toarcian, ~183 Ma). Snout and cranial robusticity differ between the species, with S. triscissus having a more robust snout and cranium and specializing in slow biting of hard prey, and H. typicus with its slender snout specializing in fast, but weaker bites on fast-moving, but soft prey. The two species did not differ in muscle forces, but stress distributions varied in the nasal area, reflecting differences when biting at different points along the tooth row: the more robustly snouted Stenopterygius resisted increases or shifts in stress distribution when the bite point was shifted from the posterior to the mid-point of the tooth row, but the slender-snouted Hauffiopteryx showed shifts and increases in stress distributions between these two bite points. The differences in cranial morphology, dentition and inferred stresses between the two species suggest adaptations for dietary niche partitioning.


Asunto(s)
Fósiles , Fragaria , Animales , Reptiles/anatomía & histología , Ecosistema , Cráneo/anatomía & histología , Evolución Biológica
9.
PeerJ ; 10: e13569, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35855428

RESUMEN

Diversification following the end-Permian mass extinction marks the initiation of Mesozoic reptile dominance and of modern marine ecosystems, yet major clades are best known from the Middle Triassic suggesting delayed recovery, while Early Triassic localities produce poorly preserved specimens or have restricted diversity. Here we describe Pomolispondylus biani gen. et sp. nov. from the Early Triassic Nanzhang-Yuan'an Fauna of China assigned to Saurosphargiformes tax. nov., a clade known only from the Middle Triassic or later, which includes Saurosphargidae, and likely is the sister taxon to Sauropterygia. Pomolispondylus biani is allied to Saurosphargidae by the extended transverse processes of dorsal vertebrae and a low, table-like dorsal surface on the neural spine; however, it does not have the typical extensive osteoderms. Rather an unusual tuberous texture on the dorsal neural spine and rudimentary ossifications lateral to the gastralia are observed. Discovery of Pomolispondylus biani extends the known range of Saurosphargiformes and increases the taxic and ecological diversity of the Nanzhang-Yuan'an Fauna. Its small size fills a different ecological niche with respect to previously found species, but the overall food web remains notably different in structure to Middle Triassic and later ecosystems, suggesting this fauna represents a transitional stage during recovery rather than its endpoint.


Asunto(s)
Ecosistema , Fósiles , Animales , Filogenia , Reptiles/anatomía & histología , China
11.
Commun Biol ; 5(1): 380, 2022 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-35484197

RESUMEN

Various Mesozoic marine reptile lineages evolved streamlined bodies and efficient lift-based swimming, as seen in modern aquatic mammals. Ichthyosaurs had low-drag bodies, akin to modern dolphins, but plesiosaurs were strikingly different, with long hydrofoil-like limbs and greatly variable neck and trunk proportions. Using computational fluid dynamics, we explore the effect of this extreme morphological variation. We find that, independently of their body fineness ratio, plesiosaurs produced more drag than ichthyosaurs and modern cetaceans of equal mass due to their large limbs, but these differences were not significant when body size was accounted for. Additionally, necks longer than twice the trunk length can substantially increase the cost of forward swimming, but this effect was cancelled out by the evolution of big trunks. Moreover, fast rates in the evolution of neck proportions in the long-necked elasmosaurs suggest that large trunks might have released the hydrodynamic constraints on necks thus allowing their extreme enlargement.


Asunto(s)
Evolución Biológica , Reptiles , Animales , Tamaño Corporal , Mamíferos , Reptiles/anatomía & histología , Natación
12.
Sci Immunol ; 7(67): eabi6899, 2022 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-34995098

RESUMEN

It is a challenge to effectively reactivate preexisting tumor-infiltrating lymphocytes (TILs) without causing severe toxicity. Interleukin-12 (IL-12) can potently activate lymphocytes, but its clinical use is limited by its short half-life and dose-related toxicity. In this study, we developed a tumor-conditional IL-12 (pro-IL-12), which masked IL-12 with selective extracellular receptor­binding domains of the IL-12 receptor while preferentially and persistently activating TILs after being unmasked by matrix metalloproteinases expressed by tumors. Systemic delivery of pro-IL-12 demonstrated reduced toxicity but better control of established tumors compared with IL-12-Fc. Mechanistically, antitumor responses induced by pro-IL-12 were dependent on TILs and IFNγ. Furthermore, direct binding of IL-12 to IL-12R on CD8+, not CD4+, T cells was essential for maximal effectiveness. Pro-IL-12 improved the efficacy of both immune checkpoint blockade and targeted therapy when used in combination. Therefore, our study demonstrated that pro-IL-12 could rejuvenate TILs, which then combined with current treatment modalities while limiting adverse effects for treating established tumors.


Asunto(s)
Interleucina-12/inmunología , Neoplasias/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Femenino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos
13.
Sci Rep ; 11(1): 21818, 2021 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-34750442

RESUMEN

The Middle Triassic Luoping Biota in south-west China represents the inception of modern marine ecosystems, with abundant and diverse arthropods, fishes and marine reptiles, indicating recovery from the Permian-Triassic mass extinction. Here we report a new specimen of the predatory marine reptile Diandongosaurus, based on a nearly complete skeleton. The specimen is larger than most other known pachypleurosaurs, and the body shape, caniniform teeth, clavicle with anterior process, and flat distal end of the anterior caudal ribs show its affinities with Diandongosaurus acutidentatus, while the new specimen is approximately three times larger than the holotype. The morphological characters indicate that the new specimen is an adult of D. acutidentatus, allowing for ontogenetic variation. The fang-like teeth and large body size confirm it was a predator, but the amputated hind limb on the right side indicate itself had been predated by an unknown hunter. Predation on such a large predator reveals that predation pressure in the early Mesozoic was intensive, a possible early hint of the Mesozoic Marine Revolution.

14.
Nat Commun ; 12(1): 2768, 2021 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-33986267

RESUMEN

As a potent lymphocyte activator, interleukin-2 (IL-2) is an FDA-approved treatment for multiple metastatic cancers. However, its clinical use is limited by short half-life, low potency, and severe in vivo toxicity. Current IL-2 engineering strategies exhibit evidence of peripheral cytotoxicity. Here, we address these issues by engineering an IL-2 prodrug (ProIL2). We mask the activity of a CD8 T cell-preferential IL-2 mutein/Fc fusion protein with IL2 receptor beta linked to a tumor-associated protease substrate. ProIL2 restores activity after cleavage by tumor-associated enzymes, and preferentially activates inside tumors, where it expands antigen-specific CD8 T cells. This significantly reduces IL-2 toxicity and mortality without compromising antitumor efficacy. ProIL2 also overcomes resistance of cancers to immune checkpoint blockade. Lastly, neoadjuvant ProIL2 treatment can eliminate metastatic cancer through an abscopal effect. Taken together, our approach presents an effective tumor targeting therapy with reduced toxicity.


Asunto(s)
Antineoplásicos/farmacología , Linfocitos T CD8-positivos/inmunología , Interleucina-2/farmacología , Neoplasias/tratamiento farmacológico , Profármacos/farmacología , Proteínas Recombinantes de Fusión/farmacología , Animales , Línea Celular Tumoral , Femenino , Humanos , Inmunoterapia/métodos , Interleucina-2/efectos adversos , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Linfotoxina-alfa/farmacología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Proteínas Recombinantes/farmacología
15.
Clin Anat ; 34(4): 550-555, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32249448

RESUMEN

INTRODUCTION: Various sacropelvic parameters such as the pelvic Incidence (PI) are used to predict ideal lumbar lordosis and aid surgical planning. The objective of this study was to establish the relationship between the location of the aortic bifurcation from the sacral promontory and sacropelvic measures including the PI. MATERIALS AND METHODS: One hundred sixty five computed tomography (CT) scans obtained for major trauma including the entire spine were identified. Sacropelvic parameters including PI, sacral anatomic orientation, pelvic thickness (PTH), and sacral table angle were measured. Aortic bifurcation was identified on sagittal and coronal imaging and the distance from the sacral promontory (bifurcation-promontory distance [BPD]) measured (mm). RESULTS: Mean age of the cohort was 44.3 years (SD 18.5; range 16-88 years); 61.8% male. The mean PI was 49.2° (SD 10.2°; range 30°-80°). The mean BPD was 66.4 mm (SD 13.1 mm; range 38.3-100 mm). In the majority, the bifurcation was at the level of the L4 vertebral body (72.7%). Only age (r = -.389; p < .0001) and PTH (r = .172; p = .027) correlated with the BPD to a significant degree. PI did not correlate with BPD (r = .061; p = .435). Linear regression analysis provided the following predictive equation: BPD = 34.3 mm + 0.30 × PTH. CONCLUSION: This study demonstrates a lack of any meaningful correlation between sagittal pelvic parameters and the distance of the aortic bifurcation from the sacral promontory. Surgical planning for fusion surgery in the lumbar spine should include assessment of spinopelvic parameters and if anterior access to the lumbar disc(s) necessary, vascular anatomy should be carefully assessed independent of these measures.


Asunto(s)
Puntos Anatómicos de Referencia , Aorta Abdominal/anatomía & histología , Aorta Abdominal/diagnóstico por imagen , Huesos Pélvicos/anatomía & histología , Huesos Pélvicos/diagnóstico por imagen , Sacro/anatomía & histología , Sacro/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Vértebras Lumbares/cirugía , Masculino , Persona de Mediana Edad , Planificación de Atención al Paciente , Fusión Vertebral/métodos , Tomografía Computarizada por Rayos X , Adulto Joven
16.
Cell Host Microbe ; 28(5): 712-723.e9, 2020 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-33113352

RESUMEN

Among mammals, bats are particularly rich in zoonotic viruses, including flaviviruses. Certain bat species can be productively yet asymptomatically infected with viruses that cause overt disease in other species. However, little is known about the antiviral effector repertoire in bats relative to other mammals. Here, we report the black flying fox receptor transporter protein 4 (RTP4) as a potent interferon (IFN)-inducible inhibitor of human pathogens in the Flaviviridae family, including Zika, West Nile, and hepatitis C viruses. Mechanistically, RTP4 associates with the flavivirus replicase, binds viral RNA, and suppresses viral genome amplification. Comparative approaches revealed that RTP4 undergoes positive selection, that a flavivirus can mutate to escape RTP4-imposed restriction, and that diverse mammalian RTP4 orthologs exhibit striking patterns of specificity against distinct Flaviviridae members. Our findings reveal an antiviral mechanism that has likely adapted over 100 million years of mammalian evolution to accommodate unique host-virus genetic conflicts.


Asunto(s)
Antivirales/inmunología , Flavivirus/efectos de los fármacos , Interacciones Huésped-Patógeno , Interferones/metabolismo , Interferones/farmacología , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/farmacología , Animales , Antivirales/farmacología , Línea Celular , Quirópteros/genética , Quirópteros/virología , Femenino , Flavivirus/genética , Genoma Viral , Interacciones Huésped-Patógeno/genética , Humanos , Interferones/genética , Masculino , Mamíferos/genética , Especificidad de la Especie , Replicación Viral , Virus/efectos de los fármacos , Virus/genética
17.
Sci Transl Med ; 12(557)2020 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-32817363

RESUMEN

The adaptive immune system recognizes tumor antigens at an early stage to eradicate cancer cells. This process is accompanied by systemic proliferation of the tumor antigen-specific T lymphocytes. While detection of asymptomatic early-stage cancers is challenging due to small tumor size and limited somatic alterations, tracking peripheral T cell repertoire changes may provide an attractive solution to cancer diagnosis. Here, we developed a deep learning method called DeepCAT to enable de novo prediction of cancer-associated T cell receptors (TCRs). We validated DeepCAT using cancer-specific or non-cancer TCRs obtained from multiple major histocompatibility complex I (MHC-I) multimer-sorting experiments and demonstrated its prediction power for TCRs specific to cancer antigens. We blindly applied DeepCAT to distinguish over 250 patients with cancer from over 600 healthy individuals using blood TCR sequences and observed high prediction accuracy, with area under the curve (AUC) ≥ 0.95 for multiple early-stage cancers. This work sets the stage for using the peripheral blood TCR repertoire for noninvasive cancer detection.


Asunto(s)
Neoplasias , Receptores de Antígenos de Linfocitos T , Antígenos de Neoplasias , Humanos , Complejo Mayor de Histocompatibilidad , Neoplasias/diagnóstico , Neoplasias/genética , Receptores de Antígenos de Linfocitos T/genética , Linfocitos T
18.
Opt Express ; 28(14): 19937-19953, 2020 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-32680063

RESUMEN

Significant advances for optical systems in terms of both performance and packaging are enabled by freeform optical components. Yet, surface form metrology for freeform optics remains a challenge. We developed and investigated a point-cloud cascade optical coherence tomography (C-OCT) technique to address this metrology challenge. The mathematical framework for the working principle of C-OCT is presented. A novel detection scheme is developed to enable high-speed measurements. Experimental results validate the C-OCT technique with the prototype setup demonstrating single-point precision of ±26 nm (∼λ/24 at the He-Ne wavelength), paving the way towards full surface measurements on freeform optical components.

19.
Am J Case Rep ; 21: e921795, 2020 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-32221270

RESUMEN

BACKGROUND SMART (Stroke-like Migraine Attacks after Radiation Therapy) syndrome is an uncommon delayed complication of cerebral radiotherapy. Less than 50 cases have been reported in the literature since it was first described in 1995. On average, presentation is about 20 years after radiotherapy, and patients commonly present with headaches, complex seizures, and stroke-like symptoms. The exact pathophysiology of the disease remains poorly understood, but one theory suggests radiation-induced vascular dysfunction. CASE REPORT We present one such case of a 28-year-old man who presented to our Emergency Department with a gradually progressive severe headache and right-sided weakness developing over a few hours. MRI played a central role in the diagnosis of SMART syndrome, with serial studies demonstrating and supporting the theory of vascular dysfunction. The condition is usually self-limiting, and most patients achieve complete recovery of symptoms, as did ours. Its optimal management remains unclear. CONCLUSIONS Better understanding of the imaging findings in SMART syndrome may help differentiate it from tumor recurrence, cerebral infections, or vasculitis. Because the diagnosis of this condition portends a significantly better prognosis and substantially alters patient expectation and management, it is important that clinicians are aware of the usual delayed presentation, symptomology, and imaging findings.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Trastornos Migrañosos/diagnóstico por imagen , Trastornos Migrañosos/etiología , Traumatismos por Radiación/complicaciones , Adulto , Diagnóstico Diferencial , Glucocorticoides/uso terapéutico , Humanos , Masculino , Metilprednisolona/uso terapéutico , Trastornos Migrañosos/tratamiento farmacológico , Convulsiones , Síndrome
20.
Commun Biol ; 3(1): 68, 2020 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-32054967

RESUMEN

How clades diversify early in their history is integral to understanding the origins of biodiversity and ecosystem recovery following mass extinctions. Moreover, diversification can represent evolutionary opportunities and pressures following ecosystem changes. Ichthyosaurs, Mesozoic marine reptiles, appeared after the end-Permian mass extinction and provide opportunities to assess clade diversification in a changed world. Using recent cladistic data, skull length data, and the most complete phylogenetic trees to date for the group, we present a combined disparity, morphospace, and evolutionary rates analysis that reveals the tempo and mode of ichthyosaur morphological evolution through 160 million years. Ichthyosaur evolution shows an archetypal early burst trend, driven by ecological opportunity in Triassic seas, and an evolutionary bottleneck leading to a long-term reduction in evolutionary rates and disparity. This is represented consistently across all analytical methods by a Triassic peak in ichthyosaur disparity and evolutionary rates, and morphospace separation between Triassic and post-Triassic taxa.


Asunto(s)
Biodiversidad , Evolución Biológica , Reptiles/anatomía & histología , Reptiles/clasificación , Animales , Organismos Acuáticos , Extinción Biológica , Fósiles , Filogenia
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