Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 76
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Cell Mol Biol (Noisy-le-grand) ; 70(8): 137-142, 2024 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-39262251

RESUMEN

Osteoporotic vertebral compression fractures (OVCFs) occur frequently in the elderly, with percutaneous vertebroplasty (PVP) being the major clinical treatment at present. How to improve the patient's surgical cooperation while ensuring surgical safety is the focus of clinical research. This study explores the influence of acupuncture anesthesia (AA) on the safety, inflammatory response, and cellular immunity of OVCF patients undergoing PVP, which may provide a more reliable safety guarantee for future treatment of OVCFs. The results showed that patients using AA had lower postoperative Visual Analogue Scale (VAS) scores and incidence of postoperative adverse reactions, a smaller anesthetic dosage, but an extended duration of anesthesia; moreover, the postoperative inflammatory response was markedly alleviated and the stability of T lymphocyte subsets was obviously enhanced. Therefore, AA has high clinical application value in PKP treatment of OVCFs in the future.


Asunto(s)
Inmunidad Celular , Inflamación , Fracturas Osteoporóticas , Humanos , Anciano , Femenino , Fracturas Osteoporóticas/inmunología , Fracturas Osteoporóticas/terapia , Inflamación/inmunología , Analgesia por Acupuntura/métodos , Masculino , Vertebroplastia/métodos , Persona de Mediana Edad , Fracturas por Compresión/terapia , Fracturas por Compresión/inmunología , Fracturas de la Columna Vertebral/terapia , Fracturas de la Columna Vertebral/inmunología , Anciano de 80 o más Años
2.
Phys Chem Chem Phys ; 26(31): 20891-20897, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39044688

RESUMEN

The commercial applications of lead halide perovskites are hindered by their negative environmental impact and inherent instability. Consequently, developing environmentally friendly copper-based perovskite materials is crucial for future solid-state lighting and display applications. In this study, an ultrafast high-power ultrasonic synthesis strategy was utilized to achieve uniform nucleation and growth of Cs3Cu2X5 (X = Cl, Br, I) nanocrystals (NCs) that possess remarkable luminescence properties, hydroxyl protection, and ligand-free characteristics. These Cs3Cu2X5 NCs exhibited a tunable spectral range spanning from 446 to 525 nm, accompanied by photoluminescence quantum yields (PLQYs) varying from 0.2% to 79.2%. The spectral attributes of the NCs were effectively controlled by modulating the halide type and composition. It is worth noting that density functional theory (DFT) calculations offer valuable insights into the synthesis of NCs and the selection of suitable alcohol solvents. Moreover, we successfully fabricated an efficient and stable white light-emitting diode (WLED) with a high luminous efficiency of 23 lm W-1 and CIE color coordinates of (0.3266, 0.3487). Our work provides a new strategy to synthesize Cs3Cu2X5 NCs and holds promise for their potential application in display and lighting devices.

3.
Chaos ; 32(9): 093143, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36182353

RESUMEN

This study investigates Caputo-Hadamard fractional differential equations on time scales. The Hadamard fractional sum and difference are defined for the first time. A general logarithm function on time scales is used as a kernel function. New fractional difference equations and their equivalent fractional sum equations are presented by the use of fundamental theorems. Gronwall inequality, asymptotical stability conditions, and two discrete-time Mittag-Leffler functions of Hadamard type are obtained. Numerical schemes are provided and chaos in fractional discrete-time logistic equation and neural network equations are reported.

4.
Br J Clin Pharmacol ; 84(12): 2747-2760, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30047605

RESUMEN

AIMS: The aim of this study is to evaluate the potential association between N-acetyltransferase type 2 (NAT2) polymorphisms and drug-induced liver injury during anti-TB treatment (AT-DILI). METHODS: We conducted a systematic review and performed a meta-analysis to clarify the role of NAT2 polymorphism in AT-DILI. PubMed, Medline and EMBASE databases were searched for studies published in English to December 31, 2017, on the association between the NAT2 polymorphism and AT-DILI risk. Outcomes were pooled with random-effects meta-analysis. Details were registered in the PROSPERO register (number: CRD42016051722). RESULTS: Thirty-seven studies involving 1527 cases and 7184 controls were included in this meta-analysis. The overall odds ratio (OR) of AT-DILI associated with NAT2 slow acetylator phenotype was 3.15 (95% CI 2.58-3.84, I2  = 51.3%, P = 0.000). The OR varied between different ethnic populations, ranging from 6.42 (95% CI 2.41-17.10, I2  = 2.3%) for the West Asian population to 2.32 (95% CI 0.58-9.24, I2  = 80.3%) for the European population. Within the slow NAT2 genotype, variation was also observed; NAT2*6/*7 was associated with the highest risk of AT-DILI (OR = 1.68, 95% CI 1.09-2.59) compared to the other slow NAT2 acetylators combined. CONCLUSIONS: NAT2 slow acetylation was observed to increase the risk of AT-DILI in tuberculosis patients. Our results support the hypothesis that the slow NAT2 genotype is a risk factor for AT-DILI.


Asunto(s)
Antituberculosos/efectos adversos , Arilamina N-Acetiltransferasa/genética , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Polimorfismo Genético , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Predisposición Genética a la Enfermedad , Genotipo , Humanos
5.
Int Orthop ; 41(2): 397-402, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27234421

RESUMEN

PURPOSE: The purpose of this study was to describe and evaluate the clinical application of the technique of interlocking intramedullary (IM) nailing via an entry point at the tip of greater trochanter using a specially designed femoral hollow trephine to stabilize diaphyseal fractures of the femur. METHODS: From February 2010 to April 2014, 35 consecutive patients with femoral shaft fractures were treated by the therapy of bone grafting from trochanter region with interlocking IM nail. The average age of these 23 male and 12 female patients was 37.5 years (range, 22-67 years). Fractures were classified according to AO classification system (15 type A, 17 type B, 3 type C). Femoral canal reaming and the collection of cancellous bone were simultaneously performed in a single step with the specially designed femoral hollow trephine, followed by regular IM nailing procedure. RESULTS: Of the 35 cases, the mean volume of spongy bone obtained was 5.63 cm3 (range, 3.0-7.0 cm3). Thirty-five patients with femoral shaft fractures had a mean follow-up period of 16.2 months (range, 12-22 months). All patients achieved bony union, at a mean of 5.4 months (range, 4-6 months). No patient developed a delayed union or a nonunion. There were no complications such as infections, injury of vascular and nerve, or heterotopic ossification in hip. CONCLUSIONS: These results indicate that the technique of use of IM nailing with the femoral hollow trephine significantly decreases the occurrence of nonunion in femoral shaft fractures.


Asunto(s)
Clavos Ortopédicos/efectos adversos , Trasplante Óseo/métodos , Fracturas del Fémur/cirugía , Fémur/cirugía , Fijación Intramedular de Fracturas/métodos , Adulto , Anciano , Trasplante Óseo/efectos adversos , Femenino , Fijación Intramedular de Fracturas/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
6.
Cell Physiol Biochem ; 36(3): 1186-96, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26111756

RESUMEN

BACKGROUND/AIMS: Osteosarcoma (OS) is the second leading cause of cancer-related death in children and young adults. Chemoresistance is the most important cause of treatment failure in OS, largely resulting from presence of cancer stem cells (CSCs). However, CSCs isolated from cancer cell lines do not necessarily represent those from primary human tumors due to accumulation of genetic aberrations that increase with passage number. Therefore, studies on CSCs from primary OS may be more important for understanding the mechanisms driving the chemoresistance of CSCs in OS. METHODS: We established a primary culture of OS cells, known as C1OS, from freshly resected tumor tissue. We further isolated CSCs from C1OS cells (C1OS-CSCs). We analyzed the effects of bufalin, a traditional Chinese medicine, on the stemness of C1OS-CSCs. We also analyzed the microRNA (miR) targets of bufalin on the stemness of C1OS-CSCs. Moreover, we examined these findings in the OS specimen. RESULTS: Bufalin inhibited the stemness of C1OS-CSCs. Moreover, we found that miR-148a appeared to be a target of bufalin, and miR-148a further regulated DNMT1 and p27 to control the stemness of OS cells. This mechanism was further confirmed in OS specimen. CONCLUSION: Our data suggest that bufalin may be a promising treatment for OS, and its function may be conducted through regulation of miR-148a.


Asunto(s)
Antineoplásicos/farmacología , Bufanólidos/farmacología , Diferenciación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica , MicroARNs/antagonistas & inhibidores , Células Madre Neoplásicas/efectos de los fármacos , Animales , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Proliferación Celular/efectos de los fármacos , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1 , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Humanos , Medicina Tradicional China , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/genética , Osteosarcoma/metabolismo , Osteosarcoma/patología , Cultivo Primario de Células , Transducción de Señal
7.
Phys Biol ; 12(5): 056002, 2015 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-26266661

RESUMEN

Post-transcriptional regulation is ubiquitous in prokaryotic and eukaryotic cells, but how it impacts gene expression remains to be fully explored. Here, we analyze a simple gene model in which we assume that mRNAs are produced in a constitutive manner but are regulated post-transcriptionally by a decapping enzyme that switches between the active state and the inactive state. We derive the analytical mRNA distribution governed by a chemical master equation, which can be well used to analyze the mechanism of how post-transcription regulation influences the mRNA expression level including the mRNA noise. We demonstrate that the mean mRNA level in the stochastic case is always higher than that in the deterministic case due to the stochastic effect of the enzyme, but the size of the increased part depends mainly on the switching rates between two enzyme states. More interesting is that we find that in contrast to transcriptional regulation, post-transcriptional regulation tends to attenuate noise in mRNA. Our results provide insight into the role of post-transcriptional regulation in controlling the transcriptional noise.


Asunto(s)
Simulación por Computador , Modelos Genéticos , Procesamiento Postranscripcional del ARN , ARN Mensajero/genética , Transcripción Genética , Algoritmos , Animales , Humanos , Biosíntesis de Proteínas , Estabilidad del ARN , ARN Mensajero/análisis , Procesos Estocásticos
8.
J Magn Reson Imaging ; 41(6): 1682-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25044870

RESUMEN

PURPOSE: To investigate the use of a newly designed machine learning-based classifier in the automatic identification of myelopathic levels in cervical spondylotic myelopathy (CSM). MATERIALS AND METHODS: In all, 58 normal volunteers and 16 subjects with CSM were recruited for diffusion tensor imaging (DTI) acquisition. The eigenvalues were extracted as the selected features from DTI images. Three classifiers, naive Bayesian, support vector machine, and support tensor machine, and fractional anisotropy (FA) were employed to identify myelopathic levels. The results were compared with clinical level diagnosis results and accuracy, sensitivity, and specificity were calculated to evaluate the performance of the developed classifiers. RESULTS: The accuracy by support tensor machine was the highest (93.62%) among the three classifiers. The support tensor machine also showed excellent capacity to identify true positives (sensitivity: 84.62%) and true negatives (specificity: 97.06%). The accuracy by FA value was the lowest (76%) in all the methods. CONCLUSION: The classifiers-based method using eigenvalues had a better performance in identifying the levels of CSM than the diagnosis using FA values. The support tensor machine was the best among three classifiers.


Asunto(s)
Vértebras Cervicales , Imagen de Difusión Tensora/métodos , Enfermedades de la Médula Espinal/clasificación , Espondilosis/clasificación , Adulto , Anciano , Anciano de 80 o más Años , Anisotropía , Teorema de Bayes , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Máquina de Vectores de Soporte
9.
Bioprocess Biosyst Eng ; 38(12): 2469-76, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26458822

RESUMEN

Quantitative models of gene regulatory activity have the potential to improve our mechanistic understanding of transcriptional regulation. However, the few models available today have been based on simplistic assumptions about the sequences being modeled or heuristic approximations of the underlying regulatory mechanisms. In this work, we have developed a thermodynamics-based model to predict gene expression driven by any DNA sequence. The proposed model relies on a continuous time, differential equation description of transcriptional dynamics. The sequence features of the promoter are exploited to derive the binding affinity which is derived based on statistical molecular thermodynamics. Experimental results show that the proposed model can effectively identify the activity levels of transcription factors and the regulatory parameters. Comparing with the previous models, the proposed model can reveal more biological sense.


Asunto(s)
Regulación de la Expresión Génica , Modelos Teóricos , Termodinámica , Transcripción Genética , Animales , Teorema de Bayes , Ritmo Circadiano , Redes Reguladoras de Genes , Ratones , Ratones Endogámicos C57BL , Núcleo Supraquiasmático/metabolismo
10.
ScientificWorldJournal ; 2014: 380106, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25045731

RESUMEN

Dynamic spectrum sharing has drawn intensive attention in cognitive radio networks. The secondary users are allowed to use the available spectrum to transmit data if the interference to the primary users is maintained at a low level. Cooperative transmission for secondary users can reduce the transmission power and thus improve the performance further. We study the joint subchannel pairing and power allocation problem in relay-based cognitive radio networks. The objective is to maximize the sum rate of the secondary user that is helped by an amplify-and-forward relay. The individual power constraints at the source and the relay, the subchannel pairing constraints, and the interference power constraints are considered. The problem under consideration is formulated as a mixed integer programming problem. By the dual decomposition method, a joint optimal subchannel pairing and power allocation algorithm is proposed. To reduce the computational complexity, two suboptimal algorithms are developed. Simulations have been conducted to verify the performance of the proposed algorithms in terms of sum rate and average running time under different conditions.


Asunto(s)
Algoritmos , Redes de Comunicación de Computadores , Humanos
11.
ScientificWorldJournal ; 2014: 625754, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24995358

RESUMEN

Reliable information processing in cells requires high sensitivity to changes in the input signal but low sensitivity to random fluctuations in the transmitted signal. There are often many alternative biological circuits qualifying for this biological function. Distinguishing theses biological models and finding the most suitable one are essential, as such model ranking, by experimental evidence, will help to judge the support of the working hypotheses forming each model. Here, we employ the approximate Bayesian computation (ABC) method based on sequential Monte Carlo (SMC) to search for biological circuits that can maintain signaling sensitivity while minimizing noise propagation, focusing on cases where the noise is characterized by rapid fluctuations. By systematically analyzing three-component circuits, we rank these biological circuits and identify three-basic-biological-motif buffering noise while maintaining sensitivity to long-term changes in input signals. We discuss in detail a particular implementation in control of nutrient homeostasis in yeast. The principal component analysis of the posterior provides insight into the nature of the reaction between nodes.


Asunto(s)
Teorema de Bayes , Simulación por Computador , Redes y Vías Metabólicas , Modelos Biológicos , Redes y Vías Metabólicas/fisiología
12.
IEEE Trans Cybern ; 54(6): 3652-3665, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38236677

RESUMEN

Alzheimer's disease (AD) is characterized by alterations of the brain's structural and functional connectivity during its progressive degenerative processes. Existing auxiliary diagnostic methods have accomplished the classification task, but few of them can accurately evaluate the changing characteristics of brain connectivity. In this work, a prior-guided adversarial learning with hypergraph (PALH) model is proposed to predict abnormal brain connections using triple-modality medical images. Concretely, a prior distribution from anatomical knowledge is estimated to guide multimodal representation learning using an adversarial strategy. Also, the pairwise collaborative discriminator structure is further utilized to narrow the difference in representation distribution. Moreover, the hypergraph perceptual network is developed to effectively fuse the learned representations while establishing high-order relations within and between multimodal images. Experimental results demonstrate that the proposed model outperforms other related methods in analyzing and predicting AD progression. More importantly, the identified abnormal connections are partly consistent with previous neuroscience discoveries. The proposed model can evaluate the characteristics of abnormal brain connections at different stages of AD, which is helpful for cognitive disease study and early treatment.


Asunto(s)
Enfermedad de Alzheimer , Encéfalo , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/fisiopatología , Humanos , Encéfalo/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Algoritmos , Aprendizaje Automático , Redes Neurales de la Computación , Anciano
13.
Artículo en Inglés | MEDLINE | ID: mdl-39137077

RESUMEN

Brain network analysis plays an increasingly important role in studying brain function and the exploring of disease mechanisms. However, existing brain network construction tools have some limitations, including dependency on empirical users, weak consistency in repeated experiments and time-consuming processes. In this work, a diffusion-based brain network pipeline, DGCL is designed for end-to-end construction of brain networks. Initially, the brain region-aware module (BRAM) precisely determines the spatial locations of brain regions by the diffusion process, avoiding subjective parameter selection. Subsequently, DGCL employs graph contrastive learning to optimize brain connections by eliminating individual differences in redundant connections unrelated to diseases, thereby enhancing the consistency of brain networks within the same group. Finally, the node-graph contrastive loss and classification loss jointly constrain the learning process of the model to obtain the reconstructed brain network, which is then used to analyze important brain connections. Validation on two datasets, ADNI and ABIDE, demonstrates that DGCL surpasses traditional methods and other deep learning models in predicting disease development stages. Significantly, the proposed model improves the efficiency and generalization of brain network construction. In summary, the proposed DGCL can be served as a universal brain network construction scheme, which can effectively identify important brain connections through generative paradigms and has the potential to provide disease interpretability support for neuroscience research.

14.
J Colloid Interface Sci ; 660: 1058-1070, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38310054

RESUMEN

Fine-tuning the surface structure of transition metal oxides at the atomic level is a promising way to improve the catalytic properties of materials. However, the influence of crystal surface structure on electrode reaction kinetics is still limited. In this study, we propose an in-situ synthesis strategy to obtain two-dimensional carbon/cerium oxide core-shell nanosheets by thermal decomposition of Ce-MOF nanosheets grown on the surface of carbon nanostructures, and fine-tuning the surface structure by introducing oxygen vacancies through defect engineering during the oxide nucleation process is conducted to obtain controllable exposed {111} and {110} surface CeO2@C composites. Both experiments and theoretical calculations show that the {110} -dominated nanocomplex (CeO2@C-350S) has better kinetic behavior and catalytic activity due to its abundant surface defects, which is manifested in higher active surface area, richer carrier concentration, and better promotion of diffusion and adsorption. In addition, CeO2@C-350S electrode has an extremely wide linear range and good stability in the electrochemical detection of nitrite. After 1000 times of the accelerated cycle experiments, CeO2@C-350S electrode still maintains 79.3 % of its initial current response, and recovers to 87.3 % after 10 min of stopping the test. The electrode stability is excellent, which is attributed to the clever carbon shell structure of the material. This synthesis strategy can be extended to other carbon-based oxide composite catalysts to improve the electrocatalytic performance and overall stability by adjusting the surface structure.

15.
J Chromatogr A ; 1736: 465390, 2024 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-39326382

RESUMEN

The occurrence of microcystins (MCs) during harmful algal blooms (HABs) represents a major threat to freshwater environments. In this work, a novel surface amphiphilic hybrid porous polymers based on cage-like organosiloxanes (PCSs) was prepared for the enrichment of MCs. The copolymerization of bifunctional amphiphilic monomers, 2-methacryloyloxyethyl phosphorylcholine (MPC) and N-benzylquininium chloride (BQN), with the cross-linker methacryl substituted polyhedral oligomeric silsesquioxane (POSS) was achieved in an ionic liquid-based porogenic medium. The hierarchical porous structure, a variety of surface functional groups and weak hydrophilicity were well characterized on the prepared materials using scanning electron microscopy, nitrogen adsorption/desorption analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, zeta potential analysis and water contact angle testing, respectively. The as-prepared surface amphiphilic PCSs was used as an adsorbent for pipette tip solid-phase extraction (PT-SPE) to enrich microcystins (MCs) from surface waters before their analysis by capillary electrochromatography (CEC) and liquid chromatography-mass spectrometry (LC-MS). Under the optimal conditions, the established PT-SPE-LC-MS method exhibited a wide linear range (10-10,000 ng L-1), low limits of detection (4.0-8.0 ng L-1) and satisfactory recoveries (89.5-102.8 %) for MCs. An adsorption mechanism involving electrostatic interactions, hydrogen bonding, hydrophilic interactions, and π-π stacking has been proposed. The findings suggest that the use of surface amphiphilic PCSs materials as adsorbents in the PT-SPE platform facilitates efficient enrichment of MCs for subsequent chromatographic analysis. These investigations offer a new perspective on the simple and uncomplicated pretreatment of complex environmental samples.

16.
ArXiv ; 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38168455

RESUMEN

Effective connectivity estimation plays a crucial role in understanding the interactions and information flow between different brain regions. However, the functional time series used for estimating effective connectivity is derived from certain software, which may lead to large computing errors because of different parameter settings and degrade the ability to model complex causal relationships between brain regions. In this paper, a brain diffuser with hierarchical transformer (BDHT) is proposed to estimate effective connectivity for mild cognitive impairment (MCI) analysis. To our best knowledge, the proposed brain diffuser is the first generative model to apply diffusion models to the application of generating and analyzing multimodal brain networks. Specifically, the BDHT leverages structural connectivity to guide the reverse processes in an efficient way. It makes the denoising process more reliable and guarantees effective connectivity estimation accuracy. To improve denoising quality, the hierarchical denoising transformer is designed to learn multi-scale features in topological space. By stacking the multi-head attention and graph convolutional network, the graph convolutional transformer (GraphConformer) module is devised to enhance structure-function complementarity and improve the ability in noise estimation. Experimental evaluations of the denoising diffusion model demonstrate its effectiveness in estimating effective connectivity. The proposed model achieves superior performance in terms of accuracy and robustness compared to existing approaches. Moreover, the proposed model can identify altered directional connections and provide a comprehensive understanding of parthenogenesis for MCI treatment.

17.
IEEE Trans Cybern ; 54(9): 5026-5039, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38324437

RESUMEN

The study of nicotine addiction mechanism is of great significance in both nicotine withdrawal and brain science. The detection of addiction-related brain connectivity using functional magnetic resonance imaging (fMRI) is a critical step in study of this mechanism. However, it is challenging to accurately estimate addiction-related brain connectivity due to the low-signal-to-noise ratio of fMRI and the issue of small sample size. In this work, a prior-embedding graph generative adversarial network (PG-GAN) is proposed to capture addiction-related brain connectivity accurately. By designing a dual-generator-based scheme, the addiction-related connectivity generator is employed to learn the feature map of addiction connection, while the reconstruction generator is used for sample reconstruction. Moreover, a bidirectional mapping mechanism is designed to maintain the consistency of sample distribution in the latent space so that addiction-related brain connectivity can be estimated more accurately. The proposed model utilizes prior knowledge embeddings to reduce the search space so that the model can better understand the latent distribution for the issue of small sample size. Experimental results demonstrate the effectiveness of the proposed PG-GAN.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Humanos , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología , Redes Neurales de la Computación , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos , Tabaquismo/diagnóstico por imagen , Tabaquismo/fisiopatología , Adulto
18.
Brain Inform ; 11(1): 1, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38190053

RESUMEN

Functional magnetic resonance imaging (fMRI) provides insights into complex patterns of brain functional changes, making it a valuable tool for exploring addiction-related brain connectivity. However, effectively extracting addiction-related brain connectivity from fMRI data remains challenging due to the intricate and non-linear nature of brain connections. Therefore, this paper proposed the Graph Diffusion Reconstruction Network (GDRN), a novel framework designed to capture addiction-related brain connectivity from fMRI data acquired from addicted rats. The proposed GDRN incorporates a diffusion reconstruction module that effectively maintains the unity of data distribution by reconstructing the training samples, thereby enhancing the model's ability to reconstruct nicotine addiction-related brain networks. Experimental evaluations conducted on a nicotine addiction rat dataset demonstrate that the proposed GDRN effectively explores nicotine addiction-related brain connectivity. The findings suggest that the GDRN holds promise for uncovering and understanding the complex neural mechanisms underlying addiction using fMRI data.

19.
Toxicol Res (Camb) ; 13(2): tfae064, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38680951

RESUMEN

Background: Postmenopausal osteoporosis (PMPO) is the most familiar type of osteoporosis, a silent bone disease. Casticin, a natural flavonoid constituent, improves osteoporosis in animal model. Nevertheless, the potential mechanism remains to be further explored. Methods: A model of PMPO was established in rats treated with ovariectomy (OVX) and RAW 264.7 cells induced with receptor activator of nuclear factor kappa-B ligand (RANKL). The effect and potential mechanism of casticin on PMPO were addressed by pathological staining, measurement of bone mineral density (BMD), three-point bending test, serum biochemical detection, filamentous-actin (F-actin) ring staining, TRAcP staining, reverse transcription quantitative polymerase chain reaction, western blot and examination of oxidative stress indicators. Results: The casticin treatment increased the femoral trabecular area, bone maturity, BMD, elastic modulus, maximum load, the level of calcium and estrogen with the reduced concentrations of alkaline phosphatase (ALP) and tumor necrosis factor (TNF)-α in OVX rats. An enhancement in the F-actin ring formation, TRAcP staining and the relative mRNA expression of NFATc1 and TRAP was observed in RANKL-induced RAW 264.7 cells, which was declined by the treatment of casticin. Moreover, the casticin treatment reversed the reduced the relative protein expression of Nrf2 and HO-1 and the concentrations of superoxide dismutase and glutathione peroxidase, and the increased content of malondialdehyde both in vivo and in vitro. Conclusion: Casticin improved bone density, bone biomechanics, the level of calcium and estrogen, the release of pro-inflammatory factor and oxidative stress to alleviate osteoporosis, which was associated with the upregulation of Nrf2/HO-1 pathway.

20.
IEEE Trans Med Imaging ; 43(9): 3161-3175, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38607706

RESUMEN

Multimodal neuroimaging provides complementary information critical for accurate early diagnosis of Alzheimer's disease (AD). However, the inherent variability between multimodal neuroimages hinders the effective fusion of multimodal features. Moreover, achieving reliable and interpretable diagnoses in the field of multimodal fusion remains challenging. To address them, we propose a novel multimodal diagnosis network based on multi-fusion and disease-induced learning (MDL-Net) to enhance early AD diagnosis by efficiently fusing multimodal data. Specifically, MDL-Net proposes a multi-fusion joint learning (MJL) module, which effectively fuses multimodal features and enhances the feature representation from global, local, and latent learning perspectives. MJL consists of three modules, global-aware learning (GAL), local-aware learning (LAL), and outer latent-space learning (LSL) modules. GAL via a self-adaptive Transformer (SAT) learns the global relationships among the modalities. LAL constructs local-aware convolution to learn the local associations. LSL module introduces latent information through outer product operation to further enhance feature representation. MDL-Net integrates the disease-induced region-aware learning (DRL) module via gradient weight to enhance interpretability, which iteratively learns weight matrices to identify AD-related brain regions. We conduct the extensive experiments on public datasets and the results confirm the superiority of our proposed method. Our code will be available at: https://github.com/qzf0320/MDL-Net.


Asunto(s)
Enfermedad de Alzheimer , Imagen Multimodal , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Imagen Multimodal/métodos , Encéfalo/diagnóstico por imagen , Neuroimagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Aprendizaje Automático , Diagnóstico Precoz , Algoritmos , Imagenología Tridimensional/métodos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA