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1.
Neuroimage ; 298: 120809, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39187220

RESUMEN

Conceptual preparation is the very initial step in language production. Endogenous semantic variables, reflecting the inherent semantic properties of concepts, could influence the productive lexical retrieval by modulating both conceptual activation and lexical selection. Yet, empirical understandings on this process and underlying mechanisms remain limited. Here, inspired by previous theoretical models and preliminary findings, we proposed a Behavioral-Neural Dual Swinging Model (DSM), revealing the swinging process between conceptual facilitation and lexical interference and extending to neural resource allocation during these processes. To further test the model, we examined the joint effect of semantic richness and semantic density on productive word retrieval both behaviorally and neurally, using a picture naming paradigm. Results nicely support the DSM by showing that the productive retrieval is driven by the swinging between semantic richness-induced conceptual facilitation primarily managed in semantic-related regions and semantic density-induced lexical interference managed in control-related regions. Moreover, the conceptual facilitation accumulated from semantic richness plays a decisive role, mitigating interference from competitors as well as the neural demands in control-related regions.


Asunto(s)
Semántica , Humanos , Femenino , Masculino , Adulto , Adulto Joven , Imagen por Resonancia Magnética , Recuerdo Mental/fisiología , Modelos Neurológicos , Mapeo Encefálico/métodos , Encéfalo/fisiología
2.
BMC Ophthalmol ; 23(1): 53, 2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36750922

RESUMEN

PURPOSE: To describe the normative profile of ophthalmic parameters in a healthy cynomolgus monkey colony, and to identify the characteristic of the spontaneous ocular disease non-human primates (NHP) models. METHODS: The NHP eye study was a cross-sectional on-site ocular examination with about 1,000 macaques held in Guangdong Province, southeastern China. The NHPs (Macaca fascicularis, cynomolgus) in this study included middle-aged individuals with a high prevalence of the ocular disease. The NHP eye study (NHPES) performed the information including systematic data and ocular data. Ocular examination included measurement of intraocular pressure (IOP), anterior segment- optical coherence tomography (OCT), slit-lamp examination, fundus photography, autorefraction, electroretinography, etc. Ocular diseases included measurement of refractive error, anisometropia, cataract, pterygium, etc. RESULTS: A total of 1148 subjects were included and completed the ocular examination. The average age was 16.4 ± 4.93 years. Compared to the male participants, the females in the NHPES had shorter axial length and the mean Average retinal nerve fiber layer (RNFL) thickness (except for the nasal quadrants). The mean IOP, anterior chamber depth, lens thickness, axial length, central corneal thickness, choroid thickness and other parameters were similar in each group. CONCLUSION: The NHPES is a unique and high-quality study, this is the first large macaque monkey cohort study focusing on ocular assessment along with comprehensive evaluation. Results from the NHPES will provide important information about the normal range of ophthalmic measurements in NHP.


Asunto(s)
Retina , Células Ganglionares de la Retina , Femenino , Animales , Masculino , Macaca fascicularis , Estudios de Cohortes , Estudios Transversales , Tomografía de Coherencia Óptica/métodos
3.
World J Surg Oncol ; 20(1): 55, 2022 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-35220968

RESUMEN

BACKGROUND: Primary undifferentiated pleomorphic sarcoma (UPS) of the pancreas is an exceedingly rare malignant tumor, with only 15 cases have been reported in the medical literature. At present, clinicians have poor recognition of the tumor, the epidemiology, diagnosis, and treatment of this disease have yet not been established. CASE PRESENTATION: In this report, we depict the clinical and imaging characteristics of a 37-year-old man presenting with a primarily cystic UPS. The patient complained of epigastric pain and distention over 20 days. Abdominal CT and pancreatic magnetic resonance imaging revealed cystic and cystic solid masses in the pancreatic body and tail. An abdominal ultrasound echogram revealed the mass in the body of the pancreas to be cystic with separation echo inside, and the wall was thick, not smooth. Besides, a hypoechoic mass was seen in the tail area of the pancreas with an inhomogeneous echoic pattern, containing small patches of no echo zone in the central. Microscopically, spindle fibroblast-like cells are arranged in a characteristic storiform pattern with pleomorphic and multinucleated cells. Immunohistochemically, tumor cells were positive for CD68 and vimentin. Seven months postoperatively, he was diagnosed with pulmonary lymph node metastasis and died 5 months later. Combined with this case report, we also reviewed the literature regarding UPS of the pancreas. CONCLUSIONS: As we know, this is the first report on ultrasonography findings of pancreatic UPS. Despite there are no distinctive manifestation of UPS, a solid cystic lesion on ultrasonography or a hypodense area in the lesion on T2-weighted imaging, should be considered for differential diagnosis with pancreatic UPS. We believe this article may add some ideas into the diagnosis and therapy of patients with this tumor.


Asunto(s)
Histiocitoma Fibroso Maligno , Neoplasias Pancreáticas , Adulto , Células Gigantes/patología , Histiocitoma Fibroso Maligno/diagnóstico , Humanos , Imagen por Resonancia Magnética , Masculino , Páncreas/diagnóstico por imagen , Páncreas/patología , Páncreas/cirugía , Neoplasias Pancreáticas/patología , Ultrasonografía
4.
Aging Dis ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38913038

RESUMEN

Ophthalmic diseases encompass a diverse range of conditions, each necessitating tailored treatment strategies. In the realm of ophthalmic research and therapeutic interventions, various subtypes of exosomes are being explored for their regenerative, neuroprotective, and anti-inflammatory properties. Exosomes have garnered increasing attention as promising therapeutic vehicles due to their natural role in cell-to-cell communication and targeted delivery capabilities. Derived from cells, these small vesicles facilitate the transportation of numerous molecules between cells, offering advantages such as low immunogenicity, stability, and precise cell targeting. These inherent qualities make exosomes an enticing avenue for advancing treatment options for ophthalmic diseases. While ongoing research and clinical applications continue to evolve, several exosome subtypes have demonstrated potential for addressing various ophthalmic conditions, including glaucoma, age-related macular degeneration, retinal degenerative disorders, and ocular inflammatory conditions.

5.
Appl Spectrosc ; 78(1): 111-119, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38055993

RESUMEN

Baseline correction is a vital part of spectral preprocessing, especially for Raman spectra. Iterative polynomial fitting is an easy but less accurate way to find baselines compared to other methods such as wavelet transform and penalized least squares (PLS) methods. The polynomial fitting methods can also get distorted results in certain conditions. In this paper, a neural network model for detecting the trend of the baseline was proposed to improve the correction accuracy of the fitting methods. The model selects the function basis according to the baseline trend instead of using a fixed polynomial function to match the baseline for a more precise fit. We also propose a way to generate simulation data, these data can be used to train the neural network model. The model provides reliable results for real spectral data with noise. Our method provides a new idea to correct the baseline with a strange shape. In addition, we examine the limitations of conventional iterative polynomial fitting, adaptive iteratively reweighted PLS and explain why our approach surpasses these methods.

6.
Clin Imaging ; 112: 110209, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38833916

RESUMEN

PURPOSE: This meta-analysis aimed to compare the diagnostic effectiveness of [18F]FDG PET/CT with that of [18F]FDG PET/MRI in terms of identifying liver metastasis in patients with primary cancer. METHODS: PubMed, Embase, Web of Science, and the Cochrane Library were searched, and studies evaluating the diagnostic efficacy of [18F]FDG PET/CT and [18F]FDG PET/MRI in patients with liver metastasis of primary cancer were included. We used a random effects model to analyze their sensitivity and specificity. Subgroup analyses and corresponding meta-regressions focusing on race, image analysis, study design, and analysis methodologies were conducted. Cochrane Q and I2 statistics were used to assess intra-group and inter-group heterogeneity. RESULTS: Seven articles with 343 patients were included in this meta-analysis. The sensitivity of [18F]FDG PET/CT was 0.82 (95 % CI: 0.63-0.96), and that of [18F]FDG PET/MRI was 0.91 (95 % CI: 0.82-0.98); there was no significant difference between the two methods (P = 0.32). Similarly, both methods showed equal specificity: 1.00 (95 % CI: 0.95-1.00) for [18F]FDG PET/CT and 1.00 (95 % CI: 0.96-1.00) for [18F]FDG PET/MRI, and thus, there was no significant difference between the methods (P = 0.41). Furthermore, the subgroup analyses revealed no differences. Meta-regression analysis revealed that race was a potential source of heterogeneity for [18F]FDG PET/CT (P = 0.01), while image analysis and contrast agent were found to be potential sources of heterogeneity for [18F]FDG PET/MRI (P = 0.02). CONCLUSIONS: [18F]FDG PET/MRI has similar sensitivity and specificity to [18F]FDG PET/CT for detecting liver metastasis of primary cancer in both the general population and in subgroups. [18F]FDG PET/CT may be a more cost-effective option. However, the conclusions of this meta-analysis are tentative due to the limited number of studies included, and further research is necessary for validation.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias Hepáticas , Imagen por Resonancia Magnética , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos , Sensibilidad y Especificidad , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Imagen Multimodal/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones/métodos
7.
Brain Sci ; 13(11)2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-38002547

RESUMEN

The use of multiple languages has been found to influence individuals' cognitive abilities. Although some studies have also investigated the effect of multilingualism on non-native language proficiency, fewer studies have focused on how multilingual experience affects native language production. This study investigated the effect of multilingualism on native language production, specifically examining control demands through a semantic Go/No-Go picture naming task. The multilingual experience was quantified using language entropy, which measures the uncertainty and diversity of language use. Control demands were achieved by manipulating the proportion of Go (i.e., naming) trials in different conditions. Results showed that as control demands increased, multilingual individuals exhibited poorer behavioral performance and greater brain activation throughout the brain. Moreover, more diverse language use was associated with higher accuracy in naming and more interconnected brain networks with greater involvement of domain-general neural resources and less domain-specific neural resources. Notably, the varied and balanced use of multiple languages enabled multilingual individuals to respond more efficiently to increased task demands during native language production.

8.
J Int Med Res ; 49(3): 3000605211001720, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33788642

RESUMEN

We present a case of an 81-year-old man with gallbladder gangrene after percutaneous vertebroplasty (PV) that was successfully treated via laparoscopic cholecystectomy (LC). The patient underwent multilevel, thoracic PV for painful osteoporotic compression fractures. PV performed at the T6 level was complicated by severe abdominal pain owing to direct embolization of the right T6 segmental artery with penetration of bone cement into the radicular artery beneath the pedicle. Cement leakage, especially arterial embolization of cement into the general circulation, is a known potential complication following PV. Serious complications related to PV augmentation procedures, such as vertebroplasty and kyphoplasty, are rare and most often result from local cement leakage or venous embolization. Combined with this case report, we reviewed the literature regarding the unusual occurrence of direct arterial cement embolization during PV and analyzed the causes to alert clinicians to this potentially rare vascular complication.


Asunto(s)
Fracturas por Compresión , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Vertebroplastia , Anciano de 80 o más Años , Cementos para Huesos , Fracturas por Compresión/diagnóstico por imagen , Fracturas por Compresión/cirugía , Vesícula Biliar , Gangrena , Humanos , Masculino , Resultado del Tratamiento
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