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1.
J Neurosci ; 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327006

RESUMO

Goal-directed visual attention is a fundamental cognitive process that enables animals to selectively focus on specific regions of the visual field while filtering out irrelevant information. However, given the domain specificity of social behaviors, it remains unclear whether attention to faces versus non-faces recruits different neurocognitive processes. In this study, we simultaneously recorded activity from temporal and frontal nodes of the attention network while macaques performed a goal-directed visual search task. V4 and inferotemporal (IT) visual category-selective units, selected during cue presentation, discriminated fixations on targets and distractors during the search, but were differentially engaged by face and house targets. V4 and IT category-selective units also encoded fixation transitions and search dynamics. Compared to distractors, fixations on targets reduced spike-LFP coherence within the temporal cortex. Importantly, target-induced desynchronization between the temporal and prefrontal cortices was only evident for face targets, suggesting that attention to faces differentially engaged the prefrontal cortex. We further revealed bidirectional theta influence between the temporal and prefrontal cortices using Granger causality, which was again disproportionate for faces. Finally, we showed that the search became more efficient with increasing target-induced desynchronization. Together, our results suggest domain specificity for attending to faces and an intricate interplay between visual attention and social processing neural networks.Significance Statement Visual attention stands as a cornerstone in the tapestry of visual perception. This study explores the neurocognitive mechanisms underlying goal-directed visual attention, specifically in the context of social versus non-social stimuli. By simultaneously recording neural activity from temporal and frontal nodes of the attention network in macaques, we elucidated how attentional processes differed when directed towards social or non-social targets. Our findings revealed distinct neural signatures for social versus non-social stimuli, suggesting domain specificity in the allocation of attentional resources. Moreover, we demonstrated an intricate interplay between visual attention and social processing neural networks, highlighting the complexity of social cognition in primates. These insights advance our understanding of the neural basis of social attention in primates.

2.
Cogn Neurodyn ; 18(4): 1977-1988, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39104695

RESUMO

Deep convolutional neural networks (CNNs) are commonly used as computational models for the primate ventral stream, while deep spiking neural networks (SNNs) incorporated with both the temporal and spatial spiking information still lack investigation. We compared performances of SNN and CNN in prediction of visual responses to the naturalistic stimuli in area V4, inferior temporal (IT), and orbitofrontal cortex (OFC). The accuracies based on SNN were significantly higher than that of CNN in prediction of temporal-dynamic trajectory and averaged firing rate of visual response in V4 and IT. The temporal dynamics were captured by SNN for neurons with diverse temporal profiles and category selectivities, and most sensitively captured around the time of peak responses for each brain region. Consistently, SNN activities showed significantly stronger correlations with IT, V4 and OFC responses. In SNN, correlations with neural activities were stronger for later time-step features than early time-step features. The temporal-dynamic prediction was also significantly improved by considering preceding neural activities during the prediction. Thus, our study demonstrated SNN as a powerful temporal-dynamic model for cortical responses to complex naturalistic stimuli.

3.
Front Neurosci ; 18: 1383844, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39145295

RESUMO

Spiking neural networks (SNNs) offer a promising energy-efficient alternative to artificial neural networks (ANNs), in virtue of their high biological plausibility, rich spatial-temporal dynamics, and event-driven computation. The direct training algorithms based on the surrogate gradient method provide sufficient flexibility to design novel SNN architectures and explore the spatial-temporal dynamics of SNNs. According to previous studies, the performance of models is highly dependent on their sizes. Recently, direct training deep SNNs have achieved great progress on both neuromorphic datasets and large-scale static datasets. Notably, transformer-based SNNs show comparable performance with their ANN counterparts. In this paper, we provide a new perspective to summarize the theories and methods for training deep SNNs with high performance in a systematic and comprehensive way, including theory fundamentals, spiking neuron models, advanced SNN models and residual architectures, software frameworks and neuromorphic hardware, applications, and future trends.

4.
Ultrasonography ; 43(5): 345-353, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39112093

RESUMO

PURPOSE: This study explored the association of the elasticity modulus and shear wave velocity (SWV) of the tibialis anterior muscle, as measured by two-dimensional shear wave elastography (2D-SWE), with the intracompartmental pressure (ICP) determined using the Whitesides method in a New Zealand rabbit model of acute compartment syndrome (ACS). Additionally, it evaluated the viability of 2D-SWE as a noninvasive, quantitative tool for the early detection of ACS. METHODS: An ACS model was established through direct external compression by applying pressure bandaging to the lower legs of 15 New Zealand rabbits using neonatal blood pressure cuffs. Another five animals represented a non-modeled control group. To measure the elasticity modulus and SWV of the tibialis anterior muscles, 2D-SWE was employed. Blood oxygen saturation, serum creatine kinase (CK), and myoglobin levels were monitored. Subsequently, the anterior tibial compartment was dissected, and the tibialis anterior was removed for hematoxylin and eosin staining to assess muscle injury. RESULTS: The elasticity modulus and SWV of the tibialis anterior muscle increased with compression duration, as did serum CK and myoglobin levels. ICP was strongly positively correlated with these parameters, particularly mean velocity (r=0.942, P<0.001) and CK (r=0.942, P<0.001). Blood oxygen saturation was negatively correlated with ICP (r=-0.887, P<0.001). Histological analysis indicated progressive muscle cell swelling over time, with damage transitioning from reversible to irreversible and culminating in necrosis. CONCLUSION: In a rabbit ACS model, ICP was strongly positively correlated with muscle elasticity modulus/SWV. Consequently, 2D-SWE may represent a novel tool for assessing early-phase ACS.

5.
Fitoterapia ; 178: 106160, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39098734

RESUMO

Patrinia punctiflora is a medical and edible Chinese herb with high nutritional and medicinal value. The continuing study of its chemical constituents led to the isolation of six iridoids, which were previously unreported compounds, patriscabioins PU (1-6). Their structures were characterized and confirmed with NMR (1D & 2D), HRMS, IR and UV. Among them, compound 5 was screened to evaluate its insulin resistance activity on an IR-HepG-2 cell model. Compound 5 had no cytotoxicity compared with the control group and could promote glucose uptake in IR-HepG-2 cells. Through further mechanism studies, the undescribed compound 5 could increase the expression levels of PI-3 K, p-AKT, GLUT4 and p-GSK3ß proteins. Moreover, the expression of PEPCK and G6Pase proteins, which are key gluconeogenic enzymes, was also inhibited. Thus, compound 5 promotes the transfer of GLUT4 to the plasma membrane by activating the PI-3 K/AKT signaling pathway, at the same time, promotes glycogen synthesis and inhibits the onset of gluconeogenesis, which in turn ameliorates insulin resistance.


Assuntos
Resistência à Insulina , Iridoides , Patrinia , Humanos , Células Hep G2 , Iridoides/farmacologia , Iridoides/isolamento & purificação , Iridoides/química , Patrinia/química , Estrutura Molecular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transportador de Glucose Tipo 4/metabolismo , Transdução de Sinais/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Gluconeogênese/efeitos dos fármacos , Glucose/metabolismo , China , Fosfatidilinositol 3-Quinases/metabolismo
6.
Front Oncol ; 14: 1427404, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015490

RESUMO

Objectives: This study aimed to explore the value of radiomics nomogram based on computed tomography (CT) on the diagnosis of benign and malignant solitary indeterminate smoothly marginated solid pulmonary nodules (SMSPNs). Methods: This study retrospectively reviewed 205 cases with solitary indeterminate SMSPNs on CT, including 112 cases of benign nodules and 93 cases of malignant nodules. They were divided into training (n=143) and validation (n=62) cohorts based on different CT scanners. Radiomics features of the nodules were extracted from the lung window CT images. The variance threshold method, SelectKBest, and least absolute shrinkage and selection operator were used to select the key radiomics features to construct the rad-score. Through multivariate logistic regression analysis, a nomogram was built by combining rad-score, clinical factors, and CT features. The nomogram performance was evaluated by the area under the receiver operating characteristic curve (AUC). Results: A total of 19 radiomics features were selected to construct the rad-score, and the nomogram was constructed by the rad-score, one clinical factor (history of malignant tumor), and three CT features (including calcification, pleural retraction, and lobulation). The nomogram performed better than the radiomics model, clinical model, and experienced radiologists who specialized in thoracic radiology for nodule diagnosis. The AUC values of the nomogram were 0.942 in the training cohort and 0.933 in the validation cohort. The calibration curve and decision curve showed that the nomogram demonstrated good consistency and clinical applicability. Conclusion: The CT-based radiomics nomogram achieved high efficiency in the preoperative diagnosis of solitary indeterminate SMSPNs, and it is of great significance in guiding clinical decision-making.

7.
bioRxiv ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38979165

RESUMO

Foveal and peripheral vision are two distinct modes of visual processing essential for navigating the world. However, it remains unclear if they engage different neural mechanisms and circuits within the visual attentional system. Here, we trained macaques to perform a free-gaze visual search task using natural face and object stimuli and recorded a large number of 14588 visually responsive neurons from a broadly distributed network of brain regions involved in visual attentional processing. Foveal and peripheral units had substantially different proportions across brain regions and exhibited systematic differences in encoding visual information and visual attention. The spike-LFP coherence of foveal units was more extensively modulated by both attention and visual selectivity, thus indicating differential engagement of the attention and visual coding network compared to peripheral units. Furthermore, we delineated the interaction and coordination between foveal and peripheral processing for spatial attention and saccade selection. Finally, the search became more efficient with increasing target-induced desynchronization, and foveal and peripheral units exhibited different correlations between neural responses and search behavior. Together, the systematic differences between foveal and peripheral processing provide valuable insights into how the brain processes and integrates visual information from different regions of the visual field. Significance Statement: This study investigates the systematic differences between foveal and peripheral vision, two crucial components of visual processing essential for navigating our surroundings. By simultaneously recording from a large number of neurons in the visual attentional neural network, we revealed substantial variations in the proportion and functional characteristics of foveal and peripheral units across different brain regions. We uncovered differential modulation of functional connectivity by attention and visual selectivity, elucidated the intricate interplay between foveal and peripheral processing in spatial attention and saccade selection, and linked neural responses to search behavior. Overall, our study contributes to a deeper understanding of how the brain processes and integrates visual information for active visual behaviors.

8.
bioRxiv ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38979217

RESUMO

Goal-directed visual attention is a fundamental cognitive process that enables animals to selectively focus on specific regions of the visual field while filtering out irrelevant information. However, given the domain specificity of social behaviors, it remains unclear whether attention to faces versus non-faces recruits different neurocognitive processes. In this study, we simultaneously recorded activity from temporal and frontal nodes of the attention network while macaques performed a goal-directed visual search task. V4 and inferotemporal (IT) visual category-selective units, selected during cue presentation, discriminated fixations on targets and distractors during the search, but were differentially engaged by face and house targets. V4 and IT category-selective units also encoded fixation transitions and search dynamics. Compared to distractors, fixations on targets reduced spike-LFP coherence within the temporal cortex. Importantly, target-induced desynchronization between the temporal and prefrontal cortices was only evident for face targets, suggesting that attention to faces differentially engaged the prefrontal cortex. We further revealed bidirectional theta influence between the temporal and prefrontal cortices using Granger causality, which was again disproportionate for faces. Finally, we showed that the search became more efficient with increasing target-induced desynchronization. Together, our results suggest domain specificity for attending to faces and an intricate interplay between visual attention and social processing neural networks.

9.
bioRxiv ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38979388

RESUMO

Visual attention and object recognition are two critical cognitive functions that significantly influence our perception of the world. While these neural processes converge on the temporal cortex, the exact nature of their interactions remains largely unclear. Here, we systematically investigated the interplay between visual attention and object feature coding by training macaques to perform a free-gaze visual search task using natural face and object stimuli. With a large number of units recorded from multiple brain areas, we discovered that units exhibiting visual feature coding displayed a distinct attentional response profile and functional connectivity compared to units not exhibiting feature coding. Attention directed towards search targets enhanced the pattern separation of stimuli across brain areas, and this enhancement was more pronounced for units encoding visual features. Our findings suggest two stages of neural processing, with the early stage primarily focused on processing visual features and the late stage dedicated to processing attention. Importantly, feature coding in the early stage could predict the attentional effect in the late stage. Together, our results suggest an intricate interplay between visual feature and attention coding in the primate brain, which can be attributed to the differential functional connectivity and neural networks engaged in these processes.

10.
Plant Sci ; 347: 112183, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38972549

RESUMO

The normal progression of mitotic cycles and synchronized development within female reproductive organs are pivotal for sexual reproduction in plants. Nevertheless, our understanding of the genetic regulation governing mitotic cycles during the haploid phase of higher plants remains limited. In this study, we characterized RNA HELICASE 32 (RH32), which plays an essential role in female gametogenesis in Arabidopsis. The rh32 heterozygous mutant was semi-sterile, whereas the homozygous mutant was nonviable. The rh32 mutant allele could be transmitted through the male gametophyte, but not the female gametophyte. Phenotypic analysis revealed impaired mitotic progression, synchronization, and cell specification in rh32 female gametophytes, causing the arrest of embryo sacs. In the delayed pollination test, none of the retarded embryo sacs developed into functional female gametophytes, and the vast majority of rh32 female gametophytes were defective in the formation of the large central vacuole. RH32 is strongly expressed in the embryo sac. Knock-down of RH32 resulted in the accumulation of unprocessed 18 S pre-rRNA, implying that RH32 is involved in ribosome synthesis. Based on these findings, we propose that RH32 plays a role in ribosome synthesis, which is critical for multiple processes in female gametophyte development.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Óvulo Vegetal , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Óvulo Vegetal/crescimento & desenvolvimento , Óvulo Vegetal/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , RNA Helicases/genética , RNA Helicases/metabolismo , Regulação da Expressão Gênica de Plantas
11.
Water Res ; 260: 121956, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38906081

RESUMO

Effective management of fecal sludge (FS) is essential for preventing environmental and public health risks. Developing safe and efficient FS treatment technology is crucial for reducing the health risks of onsite sanitation systems. In this study, bioelectrochemical toilets (BETs) were developed to treat FS onsite. Compared with the open-circuit BETs (OC-BETs), BETs exhibited higher removal efficiencies for total organic carbon, total nitrogen, and total phosphorus. Specifically, the enhancements in removal efficiencies were 18.82 ± 1.73 %, 7.28 ± 0.32 %, and 11.41 ± 0.05 % for urine, and 19.28 ± 4.08 %, 21.65 ± 1.23 %, and 24.68 ± 0.95 % for feces, respectively. Microbiome analysis indicated that the dominant populations were affiliated with electroactive bacteria (Desulfuromonas and Pseudomonas) in the electrode biofilm of BETs. The species co-occurrence network showed that the electrode biofilm microbiome in BETs had more complex correlations than that in OC-BETs, suggesting that a weak electrical current enhanced the microbiome stability. The relative abundance of antibiotic resistance genes in BETs and OC-BETs reduced by 59.85 ± 1.32 % and 53.01 ± 2.81 % compared with the initial FS, respectively. These findings indicate that BETs are an alternative system for enhancing onsite treatment of fecal sludge and provide a theoretical foundation for the implementation of BETs.


Assuntos
Fezes , Microbiota , Esgotos , Esgotos/microbiologia , Fezes/microbiologia , Resistência Microbiana a Medicamentos/genética , Eliminação de Resíduos Líquidos , Biofilmes , Bactérias/genética , Bactérias/efeitos dos fármacos
12.
Fish Shellfish Immunol ; 151: 109727, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38936520

RESUMO

Gossypol, a naturally occurring compound found in cottonseed meal, shows promising therapeutic potential for human diseases. However, within the aquaculture industry, it is considered an antinutritional factor. The incorporation of cottonseed meal into fish feed introduces gossypol, which induces intracellular stresses and hinders overall health of farmed fish. The aim of this study is to determine the role of General control nonderepressible 2 (gcn2), a sensor for intracellular stresses in gossypol-induced stress responses in fish. In the present study, we established two gcn2 knockout zebrafish lines. A feeding trial was conducted to assess the growth-inhibitory effect of gossypol in both wild type and gcn2 knockout zebrafish. The results showed that in the absence of gcn2, zebrafish exhibited increased oxidative stress and apoptosis when exposed to gossypol, resulting in higher mortality rates. In feeding trial, dietary gossypol intensified liver inflammation in gcn2-/- zebrafish, diminishing their growth and feed conversion. Remarkably, administering the antioxidant N-acetylcysteine (NAC) was effective in reversing the gossypol induced oxidative stress and apoptosis, thereby increasing the gossypol tolerance of gcn2-/- zebrafish. Exposure to gossypol induces more severe mitochondrial stress in gcn2-/- zebrafish, thereby inducing metabolic disorders. These results reveal that gcn2 plays a protective role in reducing gossypol-induced oxidative stress and apoptosis, attenuating inflammation responses, and enhancing the survivability of zebrafish in gossypol-challenged conditions. Therefore, maintaining appropriate activation of Gcn2 may be beneficial for fish fed diets containing gossypol.


Assuntos
Apoptose , Gossipol , Inflamação , Estresse Oxidativo , Peixe-Zebra , Animais , Gossipol/toxicidade , Gossipol/farmacologia , Gossipol/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Inflamação/induzido quimicamente , Ração Animal/análise , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Dieta/veterinária , Doenças dos Peixes/induzido quimicamente , Doenças dos Peixes/imunologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo
13.
Environ Sci Technol ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937254

RESUMO

Waterborne pathogens invariably present considerable threats to public health. The quorum sensing (QS) system is instrumental in coordinating bacterial growth and metabolisms. However, the responses and regulatory mechanisms of bacteria to various disinfection technologies through quorum sensing are still unclear. This study examines the inactivation effect of chlorination and ozonation on biofilms and planktonic cells of QS signaling-deficient mutants of Pseudomonas aeruginosa. Cell counting and viability assessment revealed that the combined disinfection of chlorine and ozone was the most effective for inactivating planktonic P. aeruginosa within 10 min of exposure. Additionally, microfluidic chip culture demonstrated that the secretion of quinolone signals escalated biofilms' disinfection resistance. Disinfection exposure significantly altered the gene expression of wild-type strains and QS signaling-deficient mutants. Moreover, the QS system triggered multilayered gene expression programs as a responsive protection to disinfectant exposure, including oxidative stress, ribosome synthesis, and the nutrient absorption of bacteria. These insights broaden our understanding of bacterial QS in response to disinfection, promising potential strategies toward efficient disinfection processes.

14.
Fish Physiol Biochem ; 50(4): 1483-1494, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38814520

RESUMO

Fish growth and health are predominantly governed by dietary nutrient supply. Although the beneficial effects of omega-3 polyunsaturated fatty acids supplementation have been shown in a number of fish species, the underlying mechanisms are still mostly unknown. In this study, we conducted an investigation into the effects of EPA and DHA on cell proliferation, nutrient sensing signaling, and branched-chain amino acids (BCAA) transporting in primary turbot muscle cells. The findings revealed that EPA and DHA could stimulate cell proliferation, promote protein synthesis and inhibit protein degradation through activation of target of rapamycin (TOR) signaling pathway, a pivotal nutrient-sensing signaling cascade. While downregulating the expression of myogenin and myostatin, EPA and DHA increased the level of myogenic regulatory factors, such as myoD and follistatin. Furthermore, we observed a significant increase in the concentrations of intracellular BCAAs following treatment with EPA or DHA, accompanied by an upregulation of the associated amino acid transporters. Our study providing valuable insights into the mechanisms underlying the growth-promoting effects of omega-3 fatty acids in fish.


Assuntos
Proliferação de Células , Ácidos Docosa-Hexaenoicos , Ácido Eicosapentaenoico , Linguados , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR , Animais , Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Proliferação de Células/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células Musculares/efeitos dos fármacos , Células Musculares/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Proteínas de Peixes/metabolismo
15.
Environ Res ; 252(Pt 1): 118834, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38565414

RESUMO

Iron-doped biochar has been widely used as an adsorbent to remove contaminants due to the high adsorption performance, but it still suffers from complicated preparation methods, unstable iron loading, unsatisfactory specific surface area, and uneven distribution of active sites. Here, a novel magnetic porous biochar (FeCS800) with nanostructure on surface was synthesized by one-pot pyrolysis method of corn straw with K2FeO4, and used in orange G (OG) and tetracycline (TC) adsorption. FeCS800 exhibited outstanding adsorption capacities for OG and TC after K2FeO4 activation and the adsorption data were fitted satisfactorily to Langmuir isotherm and Pseudo-second-order kinetic model. The maximum adsorption capacities of FeCS800 for OG and TC were around 303.03 mg/g and 322.58 mg/g, respectively, at 25 °C and pH 7.0, which were 16.27 and 24.61 times higher than that before modification. Thermodynamic studies showed that the adsorption of OG/TC by FeCS800 were thermodynamically favorable and highly spontaneous. And the adsorption capacity of OG and TC by FeCS800 remained 77% and 81% after 5 cycles, respectively, indicating that FeCS800 had good stability. The outstanding adsorption properties and remarkable reusability of FeCS800 show its great potential to be an economic and environmental adsorbent in contaminants removal.


Assuntos
Carvão Vegetal , Tetraciclina , Poluentes Químicos da Água , Adsorção , Tetraciclina/química , Carvão Vegetal/química , Poluentes Químicos da Água/química , Porosidade , Compostos Azo/química , Benzenossulfonatos/química , Cinética , Termodinâmica
16.
Anal Chem ; 96(23): 9370-9378, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38683892

RESUMO

The development of sensors for detection of biomarkers exhibits an exciting potential in diagnosis of diseases. Herein, we propose a novel electrochemical sensing strategy for label-free dual-biomarker detection, which is based on the combination of stimulus-responsive molecularly imprinted polymer (MIP)-modified nanopores and a polymeric membrane chronopotentiometric sensor. The ion fluxes galvanostatically imposed on the sensing membrane surface can be blocked by the recognition reaction between the target biomarker in the sample solution and the stimulus-responsive MIP receptor in the nanopores, thus causing a potential change. By using two external stimuli (i.e., pH and temperature), the recognition abilities of the stimulus-responsive MIP receptor can be effectively modulated so that dual-biomarker label-free chronopotentiometric detection can be achieved. Using alpha fetoprotein (AFP) and prostate-specific antigen (PSA) as model biomarkers, the proposed sensor offers detection limits of 0.17 and 0.42 ng/mL for AFP and PSA, respectively.


Assuntos
Biomarcadores , Polímeros Molecularmente Impressos , Nanoporos , Antígeno Prostático Específico , alfa-Fetoproteínas , Antígeno Prostático Específico/análise , Polímeros Molecularmente Impressos/química , alfa-Fetoproteínas/análise , Humanos , Biomarcadores/análise , Limite de Detecção , Técnicas Eletroquímicas/métodos , Concentração de Íons de Hidrogênio , Técnicas Biossensoriais/métodos , Potenciometria/métodos , Polímeros/química , Impressão Molecular , Temperatura
17.
Ultrasound Q ; 40(2): 104-110, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38470974

RESUMO

ABSTRACT: Patients with compensated advanced chronic liver disease (cACLD) can safely spared screening esophagogastroduodenoscopy (EGD) when they meet the Baveno VI criteria as assessed by transient elastography. Recently, the cutoff values of the Baveno VI criteria assessed by 2-dimensional shear wave elastography (2D-SWE) were proposed. We aimed to validate it to rule out high-risk varices (HRVs) in cACLD patients; combine spleen diameter (SPD) with the Baveno VI criteria and assess whether it can spare more screening EGD. A total of 173 cACLD patients with successful liver stiffness (LS) measurements and EGD examinations were included. We analyzed the risk factors that predicted HRVs and compared the performances of different models for ruling out HRVs. The platelet count, LS, and SPD were independent predictors of HRVs. The AUCs of platelet count, LS, spleen stiffness and SPD for diagnosing HRVs were 0.797, 0.757, 0.834, and 0.804, respectively. The Baveno VI criteria assessed by 2D-SWE spared 25.4% of EGD screenings and missed 2.4% of the HRV patients. Combining SPD ≤11.1 cm with the Baveno VI criteria could spare more EGD screenings than just applying the Baveno VI criteria (45.1% vs 25.4%, P < 0.001), and missed 4.9% of the HRV patients. The Baveno VI criteria assessed by 2D-SWE could be safely applied in cACLD patients to rule out HRV patients. The combined model Baveno VI/SPD could safely and significantly increase the rate of spared EGD.


Assuntos
Técnicas de Imagem por Elasticidade , Varizes Esofágicas e Gástricas , Baço , Humanos , Técnicas de Imagem por Elasticidade/métodos , Baço/diagnóstico por imagem , Feminino , Masculino , Pessoa de Meia-Idade , Varizes Esofágicas e Gástricas/diagnóstico por imagem , Idoso , Tamanho do Órgão , Estudos Retrospectivos , Adulto
18.
Front Neurosci ; 18: 1371290, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550564

RESUMO

Introduction: Spiking Neural Networks (SNNs), inspired by brain science, offer low energy consumption and high biological plausibility with their event-driven nature. However, the current SNNs are still suffering from insufficient performance. Methods: Recognizing the brain's adeptness at information processing for various scenarios with complex neuronal connections within and across regions, as well as specialized neuronal architectures for specific functions, we propose a Spiking Global-Local-Fusion Transformer (SGLFormer), that significantly improves the performance of SNNs. This novel architecture enables efficient information processing on both global and local scales, by integrating transformer and convolution structures in SNNs. In addition, we uncover the problem of inaccurate gradient backpropagation caused by Maxpooling in SNNs and address it by developing a new Maxpooling module. Furthermore, we adopt spatio-temporal block (STB) in the classification head instead of global average pooling, facilitating the aggregation of spatial and temporal features. Results: SGLFormer demonstrates its superior performance on static datasets such as CIFAR10/CIFAR100, and ImageNet, as well as dynamic vision sensor (DVS) datasets including CIFAR10-DVS and DVS128-Gesture. Notably, on ImageNet, SGLFormer achieves a top-1 accuracy of 83.73% with 64 M parameters, outperforming the current SOTA directly trained SNNs by a margin of 6.66%. Discussion: With its high performance, SGLFormer can support more computer vision tasks in the future. The codes for this study can be found in https://github.com/ZhangHanN1/SGLFormer.

19.
Comput Biol Med ; 171: 108226, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38428096

RESUMO

Stain variations pose a major challenge to deep learning segmentation algorithms in histopathology images. Current unsupervised domain adaptation methods show promise in improving model generalization across diverse staining appearances but demand abundant accurately labeled source domain data. This paper assumes a novel scenario, namely, unsupervised domain adaptation based segmentation task with incompletely labeled source data. This paper propose a Stain-Adaptive Segmentation Network with Incomplete Labels (SASN-IL). Specifically, the algorithm consists of two stages. The first stage is an incomplete label correction stage, involving reliable model selection and label correction to rectify false-negative regions in incomplete labels. The second stage is the unsupervised domain adaptation stage, achieving segmentation on the target domain. In this stage, we introduce an adaptive stain transformation module, which adjusts the degree of transformation based on segmentation performance. We evaluate our method on a gastric cancer dataset, demonstrating significant improvements, with a 10.01% increase in Dice coefficient compared to the baseline and competitive performance relative to existing methods.


Assuntos
Algoritmos , Neoplasias Gástricas , Humanos , Coloração e Rotulagem , Processamento de Imagem Assistida por Computador
20.
Medicine (Baltimore) ; 103(6): e36693, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38335423

RESUMO

RATIONALE: Inflammatory bowel disease (IBD), including Crohn disease (CD) and ulcerative colitis (UC), is a chronic immune-mediated disorder characterized by inflammation of the gastrointestinal tract. Patients with IBD are susceptible to various complications, including the coexistence of Clostridioides difficile infection (CDI). The incidence of IBD combined with difficile infection is higher in patients with compromised immune function, which can lead to increased mortality. PATIENT CONCERNS: A 43-year-old male presented with recurrent episodes of mucus and bloody stools persisting for more than a month without any identifiable triggering factors. Initially, the stool consistency was normal, but it progressively shifted to a loose and watery texture, with up to 8 occurrences daily. DIAGNOSES: This case underscores the diagnosis of severe UC through colonoscopy and colonic biopsy, along with the supplementary identification of a positive result for Clostridioides difficile in the fecal sample. INTERVENTIONS: The patient initiated infliximab therapy alongside a full vancomycin course, demonstrating the potential effectiveness of this intervention in managing early-stage ulcerative colitis with concurrent Clostridioides difficile infection. OUTCOMES: Following the completion of a full vancomycin course, the patient initiated infliximab therapy. The patient was free from significant discomfort, exhibited no fever, and had no mucopurulent bloody stools. A follow-up blood test indicated reduced inflammatory markers compared to the preoperative period, and the stools were normal. LESSONS: We illustrate the potential effectiveness of this medication by presenting an in-depth case report of a patient with early-stage UC. The report outlines the patient inclusion of infliximab to better manage UC inflammation alongside an adjunct vancomycin regimen, given the ineffectiveness of mesalazine therapy and the concurrent presence of Clostridium difficile infection. This case prompts consideration of therapeutic approaches for complex UC and contributes to advancing both research and clinical practice. Nonetheless, we should remain attentive to the variations and potential risks unique to each patient in order to formulate personalized treatment strategies.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Colite Ulcerativa , Doenças Inflamatórias Intestinais , Masculino , Humanos , Adulto , Colite Ulcerativa/tratamento farmacológico , Vancomicina/uso terapêutico , Infliximab/uso terapêutico , Antibacterianos/uso terapêutico , Doenças Inflamatórias Intestinais/complicações , Infecções por Clostridium/complicações , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/tratamento farmacológico , Inflamação/tratamento farmacológico
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