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1.
Metabolism ; 157: 155954, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38878856

RESUMO

BACKGROUND: Metabolic diseases contribute significantly to premature mortality worldwide, with increasing burdens observed among the working-age population (WAP). This study assessed global, regional, and national trends in metabolic disorders and associated mortality over three decades in WAP. METHODS: Data from the Global Burden of Disease 2019 study were leveraged to assess global metabolism-associated mortality and six key metabolic risk factors in WAP from 1990-2019. An age-period-cohort model was employed to determine the overall percentage change in mortality. RESULTS: The 2019 global metabolic risk-related mortality rate in WAP rose significantly by 50.73%, while the age-standardized mortality rate declined by 21.5%. India, China, Indonesia, the USA, and the Russian Federation were the top contributing countries to mortality in WAP, accounting for 51.01% of the total. High systolic blood pressure (HSBP), high body mass index (HBMI), and high fasting plasma glucose (HFPG) were the top metabolic risk factors for the highest mortality rates. Adverse trends in HBMI-associated mortality were observed, particularly in lower sociodemographic index (SDI) regions. HFPG-related mortality declined globally but increased in older age groups in lower SDI countries. CONCLUSIONS: Despite a general decline in metabolic risk-related deaths in WAP, increasing HBMI- and HFPG-related mortality in lower SDI areas poses ongoing public health challenges. Developing nations should prioritize interventions addressing HBMI and HFPG to mitigate mortality risks in WAP.


Assuntos
Carga Global da Doença , Humanos , Pessoa de Meia-Idade , Adulto , Masculino , Feminino , Fatores de Risco , Carga Global da Doença/tendências , Estudos de Coortes , Doenças Metabólicas/mortalidade , Doenças Metabólicas/epidemiologia , Saúde Global , Idoso , Índice de Massa Corporal , Adulto Jovem , Fatores Etários , Mortalidade/tendências
2.
Curr Biol ; 34(10): 2256-2264.e3, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38701787

RESUMO

The hippocampal formation contains neurons responsive to an animal's current location and orientation, which together provide the organism with a neural map of space.1,2,3 Spatially tuned neurons rely on external landmark cues and internally generated movement information to estimate position.4,5 An important class of landmark cue are the boundaries delimiting an environment, which can define place cell field position6,7 and stabilize grid cell firing.8 However, the precise nature of the sensory information used to detect boundaries remains unknown. We used 2-dimensional virtual reality (VR)9 to show that visual cues from elevated walls surrounding the environment are both sufficient and necessary to stabilize place and grid cell responses in VR, when only visual and self-motion cues are available. By contrast, flat boundaries formed by the edges of a textured floor did not stabilize place and grid cells, indicating only specific forms of visual boundary stabilize hippocampal spatial firing. Unstable grid cells retain internally coherent, hexagonally arranged firing fields, but these fields "drift" with respect to the virtual environment over periods >5 s. Optic flow from a virtual floor does not slow drift dynamics, emphasizing the importance of boundary-related visual information. Surprisingly, place fields are more stable close to boundaries even with floor and wall cues removed, suggesting invisible boundaries are inferred using the motion of a discrete, separate cue (a beacon signaling reward location). Subsets of place cells show allocentric directional tuning toward the beacon, with strength of tuning correlating with place field stability when boundaries are removed.


Assuntos
Sinais (Psicologia) , Células de Grade , Realidade Virtual , Animais , Células de Grade/fisiologia , Masculino , Hipocampo/fisiologia , Percepção Espacial/fisiologia , Ratos , Células de Lugar/fisiologia , Percepção Visual/fisiologia , Ratos Long-Evans , Orientação/fisiologia
3.
Mol Divers ; 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300352

RESUMO

In order to develop new natural product-based anticancer agents, a series of 1,3,4-oxadiazole analogues based on petiolide A were prepared and evaluated for their anticancer activities by MTT method. The structures of all analogues were characterized by various spectral analyses, and B9 was further confirmed by X-ray crystallography. Among all the synthesized compounds, B1 displayed the most promising growth inhibitory effect on colon cancer cells (HCT116) with the IC50 value of 8.53 µM. Flow cytometric analysis exhibited that B1 arrested the cell cycle at G2 phase and induced apoptosis. Additionally, network pharmacology analysis calculated that B1 might target several key proteins, including AKT serine/threonine kinase 1 (AKT1), SRC proto-oncogene, non-receptor tyrosine kinase (SRC) and epidermal growth factor receptor (EGFR). Furthermore, molecular docking study indicated that B1 had potentially high binding affinity to these three target proteins. Given these results, analogue B1 could be deeply developed as potential anticancer agents.

4.
PeerJ Comput Sci ; 9: e1643, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38077548

RESUMO

Telematics will be one of the critical technologies in the future intelligent transportation system and establish communication between vehicles and vehicles, vehicles and networks, and vehicles and people. Thus, vehicles can sense mobile environments and make rational driving decisions. Therefore, the safety and efficiency of traffic flow would be enhanced. However, due to the unknown nature and higher complexity of the connected network environments of vehicles, the utilization of conventional optimization theory fails to generate satisfying results. To address the problem, this article proposes a methodology for collaborative transmission for communication regarding the Internet of Vehicles (IoV) with the help of advanced computational algorithms. The article employs a multi-intelligence advanced computational algorithm to construct a collaborative communication transmission mechanism in the telematics communication system model. The proposed algorithm fully considers the vehicle mobility and quality-of-service (QoS) of telematics services within the network slice. It adjusts the slice's radio resource allocation and parameter settings on an expanded time scale to improve the QoS of telematics services and increase the system's long-term revenue. The simulation results show that the proposed algorithm has a more significant performance improvement than conventional algorithms using telematics information transmission. For example, when the same load conditions are under consideration, the total capacity of the vehicle-to-infrastructure (V2I) link optimized by the proposed algorithm is still higher than that of the other three baseline strategies.

5.
Sensors (Basel) ; 23(10)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37430721

RESUMO

An optimal method for resource allocation based on contract theory is proposed to improve energy utilization. In heterogeneous networks (HetNets), distributed heterogeneous network architectures are designed to balance different computing capacities, and MEC server gains are designed based on the amount of allocated computing tasks. An optimal function based on contract theory is developed to optimize the revenue gain of MEC servers while considering constraints such as service caching, computation offloading, and the number of resources allocated. As the objective function is a complex problem, it is solved utilizing equivalent transformations and variations of the reduced constraints. A greedy algorithm is applied to solve the optimal function. A comparative experiment on resource allocation is conducted, and energy utilization parameters are calculated to compare the effectiveness of the proposed algorithm and the main algorithm. The results show that the proposed incentive mechanism has a significant advantage in improving the utility of the MEC server.

6.
Molecules ; 28(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37298778

RESUMO

A simple and efficient hydroxide-mediated SNAr rearrangement was reported to synthesize new depside derivatives containing the diaryl ether skeleton from the natural product barbatic acid. The prepared compounds were determined using 1H NMR, 13C NMR, HRMS, and X-ray crystallographic analysis and were also screened in vitro for cytotoxicity against three cancer cell lines and one normal cell line. The evaluation results showed that compound 3b possessed the best antiproliferative activity against liver cancer HepG2 cell line and low toxicity, which made it worth further study.


Assuntos
Antineoplásicos , Depsídeos , Depsídeos/farmacologia , Linhagem Celular Tumoral , Éter/farmacologia , Antineoplásicos/química , Éteres/química , Etil-Éteres , Esqueleto , Ensaios de Seleção de Medicamentos Antitumorais , Relação Estrutura-Atividade , Proliferação de Células , Estrutura Molecular
9.
Sensors (Basel) ; 23(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36991631

RESUMO

A distributed GM-CPHD filter based on parallel inverse covariance crossover is designed to attenuate the local filtering and uncertain time-varying noise affecting the accuracy of sensor signals. First, the GM-CPHD filter is identified as the module for subsystem filtering and estimation due to its high stability under Gaussian distribution. Second, the signals of each subsystem are fused by invoking the inverse covariance cross-fusion algorithm, and the convex optimization problem with high-dimensional weight coefficients is solved. At the same time, the algorithm reduces the burden of data computation, and data fusion time is saved. Finally, the GM-CPHD filter is added to the conventional ICI structure, and the generalization capability of the parallel inverse covariance intersection Gaussian mixture cardinalized probability hypothesis density (PICI-GM-CPHD) algorithm reduces the nonlinear complexity of the system. An experiment on the stability of Gaussian fusion models is organized and linear and nonlinear signals are compared by simulating the metrics of different algorithms, and the results show that the improved algorithm has a smaller metric OSPA error than other mainstream algorithms. Compared with other algorithms, the improved algorithm improves the signal processing accuracy and reduces the running time. The improved algorithm is practical and advanced in terms of multisensor data processing.

10.
Sensors (Basel) ; 24(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38202936

RESUMO

Mobile edge computing is critical for improving the user experience of latency-sensitive and freshness-based applications. This paper provides insights into the potential of non-orthogonal multiple access (NOMA) convergence with heterogeneous air-ground collaborative networks to improve system throughput and spectral efficiency. Coordinated resource allocation between UAVs and MEC servers, especially in the NOMA framework, is addressed as a key challenge. Under the unrealistic assumption that edge nodes contribute resources indiscriminately, we introduce a two-stage incentive mechanism. The model is based on contract theory and aims at optimizing the utility of the service provider (SP) under the constraints of individual rationality (IR) and incentive compatibility (IC) of the mobile user. The block coordinate descent method is used to refine the contract design and complemented by a generative diffusion model to improve the efficiency of searching for contracts. During the deployment process, the study emphasizes the positioning of UAVs to maximize SP effectiveness. An improved differential evolutionary algorithm is introduced to optimize the positioning of UAVs. Extensive evaluation shows our approach has excellent effectiveness and robustness in deterministic and unpredictable scenarios.

11.
Sensors (Basel) ; 24(1)2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38202980

RESUMO

A highly efficient implementation method for distributed fusion in sensor networks based on CPHD filters is proposed to address the issues of unknown cross-covariance fusion estimation and long fusion times in multi-sensor distributed fusion. This method can effectively and efficiently fuse multi-node information in multi-target tracking applications. Discrete gamma cardinalized probability hypothesis density (DG-CPHD) can effectively reduce the computational burden while ensuring computational accuracy similar to that of CPHD filters. Parallel inverse covariance intersection (PICI) can effectively avoid solving high-dimensional weight coefficient convex optimization problems, reduce the computational burden, and efficiently implement filtering fusion strategies. The effectiveness of the algorithm is demonstrated through simulation results, which indicate that PICI-GM-DG-CPHD can substantially reduce the computational time compared to other algorithms and is more suitable for distributed sensor fusion.

12.
Sensors (Basel) ; 22(20)2022 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-36298127

RESUMO

Soil organic matter (SOM) is an important source of nutrients required during crop growth and is an important component of cultivated soil. In this paper, we studied the possibility of using deep learning methods to establish a multi-feature model to predict SOM content. Moreover, using Nong'an County of Changchun City as the study area, Sentinel-2A remote sensing images were taken as the data source to construct the dataset by using field sampling and image processing. The LeNet-5 convolutional neural network model was chosen as the deep learning model, which was improved based on the basic model. The evaluation metrics were selected as the root mean square error (RMSE) and the coefficient of determination R2. Through comparison, the R2 of the improved model was found to be higher than that of the linear regression method, Support Vector Machines (SVM) (RMSE = 2.471, R2 = 0.4035), and Random Forest (RF) (RMSE = 2.577, R2 = 0.4913). The result shows that: (1) It is feasible to use the multispectral data extracted from remote sensing images for soil organic matter content inversion based on the deep learning model with a minimum RMSE of 2.979 and with the R2 reaching 0.89. (2) The choice of features has an impact on the prediction of the model to a certain extent. After ranking the importance of features, selecting the appropriate number of features for inversion provides better results than full feature inversion, and the computational speed is improved.


Assuntos
Redes Neurais de Computação , Solo , Análise de Regressão , Modelos Lineares , Máquina de Vetores de Suporte
13.
Nephrology (Carlton) ; 27(12): 994-1002, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36164928

RESUMO

AIM: Gestational diabetes mellitus (GDM) is the most common complication in pregnancy. This study aimed to investigate the potential mechanism and effects of long-noncoding RNA maternally expressed 8 (lncRNA-MEG8) in GDM. METHODS: Targeted interactions involving lncRNA-MEG8 and miR-296-3p were initially predicted using starBase software and then confirmed using dual-luciferase reporter gene analysis. The expression levels of lncRNA-MEG8 and miR-296-3p in peripheral blood samples from patients with GDM were measured using reverse transcription-quantitative polymerase chain reaction. Enzyme-linked immunosorbent assay was used to evaluate the overall levels of insulin and insulin secretion. Additionally, MTT and flow cytometric methods were used to detect cell viability and apoptosis. Cell apoptosis-associated proteins were determined by western blotting. RESULTS: Our results indicated that lncRNA-MEG8 is a potential target of miR-296-3p. lncRNA-MEG8 level was higher, whereas that of miR-296-3p was lower in patients with GDM than in healthy individuals. LncRNA-MEG8-siRNA promoted insulin content and secretion. Furthermore, MEG8-siRNA increased cell viability and decreased apoptosis. However, these changes were reversed by an miR-296-3p inhibitor. Moreover, a miR-296-3p mimic had the same effect on INS-1 cells as MEG8-siRNA, as evidenced by enhanced insulin secretion, cell viability, and reduced apoptosis. CONCLUSION: LncRNA-MEG8-siRNA promotes pancreatic ß-cell function by upregulating miR-296-3p.


Assuntos
Diabetes Gestacional , Insulinas , MicroRNAs , RNA Longo não Codificante , Feminino , Gravidez , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Diabetes Gestacional/genética , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Interferente Pequeno/farmacologia , Proliferação de Células , Apoptose , Insulinas/farmacologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-35061576

RESUMO

An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was developed using a highly sensitive and specific monoclonal antibody against avilamycin. The immunising antigen synthesised through the carbonyldiimidazole (CDI) method was used to prepare antibodies. The established ic-ELISA, after optimisation of conditions, possessed a half maximum inhibitory concentration (IC50) value of 7.44 ng mL-1 and the detection limit of 0.21 ng mL-1 in the standard curve. The spiked experiments indicated that the limits of detection were 1.86 µg kg-1 and 2.31 µg kg-1 in swine feed and chicken feed, respectively. In addition, the average recoveries ranged from 74.7 to 105.4% with the coefficient of variation less than 11%. The good correlation (R2 = 0.9818) between the result of ic-ELISA and HPLC demonstrated the reliability of the developed ic-ELISA, which showed that the ic-ELISA developed here achieves the aim of strengthening the monitoring of avilamycin residues and the inspection of import and export related products.


Assuntos
Anticorpos Monoclonais , Oligossacarídeos , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Reprodutibilidade dos Testes , Suínos
15.
Zhongguo Zhen Jiu ; 41(5): 479-84, 2021 May 12.
Artigo em Chinês | MEDLINE | ID: mdl-34002558

RESUMO

OBJECTIVE: To observe the effect of abdominal penetrating moxibustion on strength and endurance of core muscle group in patients with stroke. METHODS: Sixty-two patients with stroke were randomly divided into an observation group (31 cases, 2 cases dropped off) and a control group (31 cases, 2 cases dropped off). The patients in the control group were treated with routine basic treatment, acupuncture treatment and rehabilitation training; based on the treatment of the control group, the patients in the observation group were treated with abdominal penetrating moxibustion, approximately 50 min each time, once a day. The treatments in the two groups were given 5 times a week for 4 weeks. The root mean square (RMS) and median frequency (MF) of bilateral transverse abdominis and multifidus of performing sitting-standing and making steps were measured by surface electromyography before and after treatment. The postural assessment scale for stroke (PASS), Berg balance scale (BBS) and lower-limb Fugl-Meyer motor assessment (FMA) scores were observed before treatment, 2 weeks into treatment and 4 weeks into treatment. RESULTS: Compared before treatment, when performing different postures, the RMS and MF of bilateral transversus abdominis and multifidus in the two groups were increased after treatment (P<0.01, P<0.05). The RMS of affected-side transversus abdominis and multifidus and the MF value of bilateral transverse abdominis and multifidus in the observation group were higher than those in the control group (P<0.05). Compared before treatment, the PASS, BBS and FMA scores were increased 4 weeks into treatment in the two groups (P<0.01), and those in the observation group were higher than the control group (P<0.01). CONCLUSION: The abdominal penetrating moxibustion could effectively improve the strength and endurance of core muscle group, improve the posture control, balance ability and lower-limb motor function in patients with stroke.


Assuntos
Terapia por Acupuntura , Moxibustão , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Músculos Abdominais , Eletromiografia , Humanos , Acidente Vascular Cerebral/terapia , Resultado do Tratamento
16.
Cell ; 183(5): 1249-1263.e23, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33181068

RESUMO

The hippocampal-entorhinal system is important for spatial and relational memory tasks. We formally link these domains, provide a mechanistic understanding of the hippocampal role in generalization, and offer unifying principles underlying many entorhinal and hippocampal cell types. We propose medial entorhinal cells form a basis describing structural knowledge, and hippocampal cells link this basis with sensory representations. Adopting these principles, we introduce the Tolman-Eichenbaum machine (TEM). After learning, TEM entorhinal cells display diverse properties resembling apparently bespoke spatial responses, such as grid, band, border, and object-vector cells. TEM hippocampal cells include place and landmark cells that remap between environments. Crucially, TEM also aligns with empirically recorded representations in complex non-spatial tasks. TEM also generates predictions that hippocampal remapping is not random as previously believed; rather, structural knowledge is preserved across environments. We confirm this structural transfer over remapping in simultaneously recorded place and grid cells.


Assuntos
Córtex Entorrinal/fisiologia , Generalização Psicológica , Hipocampo/fisiologia , Memória/fisiologia , Modelos Neurológicos , Animais , Conhecimento , Células de Lugar/citologia , Sensação , Análise e Desempenho de Tarefas
17.
Nat Commun ; 10(1): 630, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30733457

RESUMO

Place and grid cells in the hippocampal formation provide foundational representations of environmental location, and potentially of locations within conceptual spaces. Some accounts predict that environmental sensory information and self-motion are encoded in complementary representations, while other models suggest that both features combine to produce a single coherent representation. Here, we use virtual reality to dissociate visual environmental from physical motion inputs, while recording place and grid cells in mice navigating virtual open arenas. Place cell firing patterns predominantly reflect visual inputs, while grid cell activity reflects a greater influence of physical motion. Thus, even when recorded simultaneously, place and grid cell firing patterns differentially reflect environmental information (or 'states') and physical self-motion (or 'transitions'), and need not be mutually coherent.


Assuntos
Células de Grade/metabolismo , Células de Lugar/metabolismo , Animais , Células de Grade/citologia , Hipocampo/metabolismo , Hipocampo/fisiologia , Neurônios/citologia , Neurônios/metabolismo , Células de Lugar/citologia , Percepção Espacial/fisiologia
18.
Science ; 362(6414): 520-521, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30385559

Assuntos
Encéfalo , Postura
19.
Elife ; 72018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29911974

RESUMO

We present a mouse virtual reality (VR) system which restrains head-movements to horizontal rotations, compatible with multi-photon imaging. This system allows expression of the spatial navigation and neuronal firing patterns characteristic of real open arenas (R). Comparing VR to R: place and grid, but not head-direction, cell firing had broader spatial tuning; place, but not grid, cell firing was more directional; theta frequency increased less with running speed, whereas increases in firing rates with running speed and place and grid cells' theta phase precession were similar. These results suggest that the omni-directional place cell firing in R may require local-cues unavailable in VR, and that the scale of grid and place cell firing patterns, and theta frequency, reflect translational motion inferred from both virtual (visual and proprioceptive) and real (vestibular translation and extra-maze) cues. By contrast, firing rates and theta phase precession appear to reflect visual and proprioceptive cues alone.


Assuntos
Potenciais de Ação/fisiologia , Córtex Entorrinal/fisiologia , Hipocampo/fisiologia , Orientação/fisiologia , Percepção Espacial/fisiologia , Navegação Espacial/fisiologia , Percepção Visual/fisiologia , Animais , Sinais (Psicologia) , Eletrodos Implantados , Córtex Entorrinal/anatomia & histologia , Córtex Entorrinal/citologia , Células de Grade/citologia , Células de Grade/fisiologia , Movimentos da Cabeça/fisiologia , Hipocampo/anatomia & histologia , Hipocampo/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Neurológicos , Células de Lugar/citologia , Células de Lugar/fisiologia , Restrição Física/instrumentação , Restrição Física/métodos , Técnicas Estereotáxicas , Ritmo Teta/fisiologia , Interface Usuário-Computador
20.
Sci Rep ; 7(1): 5637, 2017 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-28717183

RESUMO

Interneurons are important for computation in the brain, in particular, in the information processing involving the generation of theta oscillations in the hippocampus. Yet the functional role of interneurons in the theta generation remains to be elucidated. Here we use time-delayed mutual information to investigate information flow related to a special class of interneurons-theta-driving neurons in the hippocampal CA1 region of the mouse-to characterize the interactions between theta-driving neurons and theta oscillations. For freely behaving mice, our results show that information flows from the activity of theta-driving neurons to the theta wave, and the firing activity of theta-driving neurons shares a substantial amount of information with the theta wave regardless of behavioral states. Via realistic simulations of a CA1 pyramidal neuron, we further demonstrate that theta-driving neurons possess the characteristics of the cholecystokinin-expressing basket cells (CCK-BC). Our results suggest that it is important to take into account the role of CCK-BC in the generation and information processing of theta oscillations.


Assuntos
Região CA1 Hipocampal/fisiologia , Interneurônios/fisiologia , Algoritmos , Animais , Colecistocinina/metabolismo , Camundongos
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