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1.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1749-1761, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38812187

RESUMO

Shenling Baizhu San(SLBZS) is a commonly used medicine for the treatment of ulcerative colitis(UC). This study aims to explore the mechanism of SLBZS in treating UC by using colonic metabolomics and network pharmacology. BALB/c mice were randomly divided into four groups: a blank group, a model group, an SLBZS group, and a sulfasalazine group. UPLC-Q-TOF-MS/MS technology was utilized to analyze the metabolic profiles of colonic tissue in mice, and differential metabolites and related metabolic pathways were screened. Based on the online database, active ingredients, action targets, and UC disease targets of SLBZS were screened. The protein-protein interaction(PPI) network of core targets of SLBZS in treating UC was constructed using STRING and Cytoscape 3.9.1. Gene Ontology(GO) functional and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analyses were performed using the DAVID database. A "metabolite-reaction-enzyme-gene" network was constructed to conduct a combined analysis of metabolomics and network pharmacology. SLBZS reversed the levels of 25 metabolites involved in various pathways such as D-glutamine and D-glutamate metabolism, caffeine metabolism, sphingolipid metabolism, arginine biosynthesis, lysine degradation, alanine, aspartate, and glutamate metabolism, glycerophospholipid metabolism, and pyrimidine metabolism in UC colonic tissue. 47 core targets of SLBZS in treating UC were involved in pathways including the MAPK signaling pathway, TNF signaling pathway, Toll-like receptor signaling pathway, lipid and atherosclerosis, inflammatory bowel disease, and Th17 cell differentiation. Integrated analysis showed that glycerophospholipid metabolism and pyrimidine metabolism were key metabolic pathways in the treatment of UC with SLBZS. The results suggested that SLBZS improved colonic mucosal morphology by regulating colonic metabolites, down-regulated the expression of inflammation-related core target genes to reduce inflammation levels, and alleviated lipid metabolism disorders, thereby exerting a therapeutic effect on UC.


Assuntos
Colite Ulcerativa , Colo , Medicamentos de Ervas Chinesas , Metabolômica , Camundongos Endogâmicos BALB C , Farmacologia em Rede , Animais , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Colite Ulcerativa/genética , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Camundongos , Colo/metabolismo , Colo/efeitos dos fármacos , Masculino , Humanos , Mapas de Interação de Proteínas
3.
Urolithiasis ; 51(1): 118, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37796347

RESUMO

The Holmium (Ho:YAG) laser is presently the most extensively employed in laser lithotripsy for the management of kidney stones. Despite its adoption as the gold standard for laser lithotripsy, Ho:YAG laser lithotripsy poses three significant challenges, namely thermal effect, insufficient stone fragmentation, and stone displacement, which have garnered increased attention from urologic surgeons. Nowadays, the femtosecond laser is regarded as a potential alternative to the Ho:YAG laser due to its capacity to ablate diverse materials with minimal thermal effect. In our ex vivo investigation, we assessed the dimensions of ablation pits, the efficacy of ablation, the degree of stone fragmentation, the alterations in water temperature surrounding stones, and the degree of tissue damage associated with Femtosecond laser lithotripsy utilizing adjustable power settings (1-50 W). Our findings indicate that the ablation pits generated by the Femtosecond laser exhibited uniform geometries, and the effectiveness of ablation and fragmentation for Femtosecond laser lithotripsy were significantly and positively correlated with laser power. When the laser power remained constant, the Femtosecond laser with higher pulse energy demonstrated superior efficiency in stone ablation, but inferior performance in stone fragmentation. Conversely, the Femtosecond laser with higher pulse frequency exhibited the opposite behavior. Furthermore, the thermal effect increased proportionally with laser power, leading to a tentative recommendation of 10W laser power for future investigations. Our in vitro findings suggest that the Femtosecond laser holds promise as a safe and effective alternative to holmium lasers.


Assuntos
Cálculos Renais , Lasers de Estado Sólido , Litotripsia a Laser , Litotripsia , Humanos , Litotripsia a Laser/efeitos adversos , Litotripsia a Laser/métodos , Litotripsia/efeitos adversos , Cálculos Renais/cirurgia , Lasers de Estado Sólido/uso terapêutico , Hólmio
4.
Front Cell Infect Microbiol ; 13: 1142426, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37265501

RESUMO

Background: The identification of uropathogens (UPBs) and urinary tract colonizing bacteria (UCB) conduces to guide the antimicrobial therapy to reduce resistant bacterial strains and study urinary microbiota. This study established a nomogram based on the nanopore-targeted sequencing (NTS) and other infectious risk factors to distinguish UPB from UCB. Methods: Basic information, medical history, and multiple urine test results were continuously collected and analyzed by least absolute shrinkage and selection operator (LASSO) regression, and multivariate logistic regression was used to determine the independent predictors and construct nomogram. Receiver operating characteristics, area under the curve, decision curve analysis, and calibration curves were used to evaluate the performance of the nomogram. Results: In this study, the UPB detected by NTS accounted for 74.1% (401/541) of all urinary tract microorganisms. The distribution of ln(reads) between UPB and UCB groups showed significant difference (OR = 1.39; 95% CI, 1.246-1.551, p < 0.001); the reads number in NTS reports could be used for the preliminary determination of UPB (AUC=0.668) with corresponding cutoff values being 7.042. Regression analysis was performed to determine independent predictors and construct a nomogram, with variables ranked by importance as ln(reads) and the number of microbial species in the urinary tract of NTS, urine culture, age, urological neoplasms, nitrite, and glycosuria. The calibration curve showed an agreement between the predicted and observed probabilities of the nomogram. The decision curve analysis represented that the nomogram would benefit clinical interventions. The performance of nomogram with ln(reads) (AUC = 0.767; 95% CI, 0.726-0.807) was significantly better (Z = 2.304, p-value = 0.021) than that without ln(reads) (AUC = 0.727; 95% CI, 0.681-0.772). The rate of UPB identification of nomogram was significantly higher than that of ln(reads) only (χ2 = 7.36, p-value = 0.009). Conclusions: NTS is conducive to distinguish uropathogens from colonizing bacteria, and the nomogram based on NTS and multiple independent predictors has better prediction performance of uropathogens.


Assuntos
Microbiota , Sequenciamento por Nanoporos , Nanoporos , Nomogramas , Bactérias/genética
5.
Front Oncol ; 13: 1142441, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937437

RESUMO

Background: Lymphovascular invasion (LVI) is a high-risk factor for testicular germ-cell tumors (TGCT), but a prognostic model for TGCT-LVI patients is lacking. This study aimed to develop a nomogram for predicting the overall survival (OS) of TGCT-LVI patients. Methods: A complete cohort of 3288 eligible TGCG-LVI patients (training cohort, 2300 cases; validation cohort, 988 cases) were obtained from the Surveillance, Epidemiology, and End Results database. Variables screened by multivariate Cox regression analysis were used to construct a nomogram, which was subsequently evaluated using the consistency index (C-index), time-dependent receiver operating characteristic curve (ROC), and calibration plots. The advantages and disadvantages of the American Joint Committee on Cancer (AJCC) staging system and the nomogram were assessed by integrated discrimination improvement (IDI) and net reclassification improvement (NRI). Decision-analysis curve (DCA) was used to measure the net clinical benefit of the nomogram versus the AJCC staging system. Finally, Kaplan-Meier curves were used to evaluate the ability to identify different risk groups between the traditional AJCC staging system and the new risk-stratification system built on the nomogram. Results: Nine variables were screened by multivariate Cox regression analysis to construct the nomogram. The C-index (training cohort, 0.821; validation cohort, 0.819) and time-dependent ROC of 3-, 5-, and 9-year OS between the two cohorts suggested that the nomogram had good discriminatory ability. Calibration curves showed good consistency of the nomogram. The NRI values of 3-, 5-, and 9-year OS were 0.308, 0.274, and 0.295, respectively, and the corresponding values for the validation cohort were 0.093, 0.093, and 0.099, respectively (P<0.01). Additionally, the nomogram had more net clinical benefit as shown by the DCA curves, and the new risk-stratification system provided better differentiation than the AJCC staging system. Conclusions: A prognostic nomogram and new risk-stratification system were developed and validated to assist clinicians in assessing TGCT-LVI patients.

6.
Entropy (Basel) ; 25(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36673242

RESUMO

In this paper, we conduct a survey of the literature about reinforcement learning (RL)-based medium access control (MAC) protocols. As the scale of the wireless ad hoc network (WANET) increases, traditional MAC solutions are becoming obsolete. Dynamic topology, resource allocation, interference management, limited bandwidth and energy constraint are crucial problems needing resolution for designing modern WANET architectures. In order for future MAC protocols to overcome the current limitations in frequently changing WANETs, more intelligence need to be deployed to maintain efficient communications. After introducing some classic RL schemes, we investigate the existing state-of-the-art MAC protocols and related solutions for WANETs according to the MAC reference model and discuss how each proposed protocol works and the challenging issues on the related MAC model components. Finally, this paper discusses future research directions on how RL can be used to enable MAC protocols for high performance.

7.
Entropy (Basel) ; 24(5)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35626492

RESUMO

Along with the fast development of the marine economy and ever-increasing human activities, handy and reliable marine networking services are increasingly required in recent years. The ocean faces challenges to support cost-effective communication due to its special environments. Opportunistic networks with easy deployment and self-curing capability are expected to play an important role to adapt to such dynamic networking environments. In the literature, routing schemes for opportunistic networks mainly exploit node mobility and local relaying technologies. They did not take into account the impact of node behaviors on encountering opportunities and in case of no further relaying, network performance would be greatly degraded. To solve the problem, we propose an efficient routing scheme based on node attributes for opportunistic networks. We first construct delivery competency to predict the further relay nodes. Then a forwarding willingness mechanism is introduced to evaluate the relaying probability combining device capacity and movement behaviors of nodes. Finally, the utility metric is used to make decisions on message forwarding. The results show that the proposed scheme improves network performance in terms of delivery ratio, average latency, and overhead ratio as compared to other schemes.

8.
Materials (Basel) ; 15(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35591394

RESUMO

The development of accident-tolerant materials is of great significance for preventing the zirconium-water reactions and improving the inherent safety of nuclear reactors. In this study, ZrC/Ni multilayers with average layer thicknesses of 5, 10, 20, 50, and 100 nm were designed and successfully fabricated by magnetron sputtering. The characterization results of GIXRD, SEM, AFM, TEM, etc., show that the series of films are mainly composed of alternately deposited Ni crystalline layers and ZrC amorphous layers, and the interface is clear. The films were irradiated with 50 keV He+ with a fluence of 1.0 × 1017 ions/cm2 at room temperature, and the films with different layer thicknesses kept the original phase composition. It was found that an amorphous transition layer with a thickness of about 30 nm appeared between the amorphous and crystalline interface of the 100 nm film by TEM characterization. The analysis shows that this layer is formed by the mixing of Ni and Zr elements induced by irradiation, which is not conducive to He+ migration and produces large-sized helium bubbles. The appearance of the transition layer improves the irradiation stability of the amorphous/crystalline composite film, thus providing a theoretical basis for the application of this type of material in fuel cladding.

9.
Nanomaterials (Basel) ; 12(7)2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35407312

RESUMO

Two different of Sm-loading fluorapatite (Ca10-2xNaxSmx(PO4)6F2, x = 1 and 2) glass-ceramics were synthesized by a two-step melt sintering method. The samples were irradiated with 50 keV He+ ions with a fluence of 2.6 × 1016 ions/cm2 at 593 K. The irradiation induced microstructural evolution were characterized by grazing incidence X-ray diffraction and cross-sectional transmission electron microscopy. For the smaller Sm-doping samples, no phase transformation is observed. Meanwhile, in the lager Sm-doping samples, the irradiation induced the crystals into smaller nanocrystals. The mechanism of the transformation of the crystalline phase was also analyzed and discussed.

10.
J Phys Chem B ; 126(4): 964-975, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35076239

RESUMO

The structures of a single polyethylene chain were investigated using all-atom molecular dynamics simulations with a series of cutoff distances. We found that a long single chain with a short cutoff distance undergoes coil, globule, and crystal states during a continuous cooling process. The globule state vanishes for short chains less than a certain length where there is large conformational fluctuation. A tight-folding model was applied to analyze the folded structures, and the re-entry modes show that a shorter chain prefers the nearest folding while a longer one prefers the second or third nearest folding. Our results show that a single polyethylene chain can exhibit condensed phenomena of state transitions, which could be heuristic for single-chain physics and polymer crystallization.


Assuntos
Simulação de Dinâmica Molecular , Polietileno , Cristalização , Conformação Molecular , Transição de Fase
11.
Materials (Basel) ; 14(13)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34279301

RESUMO

The FeCoNiCrTi0.2 high-entropy alloys fabricated by vacuum arc melting method, and the annealed pristine material, are face centered cubic structures with coherent γ' precipitation. Samples were irradiated with 50 keV He+ ions to a fluence of 2 × 1016 ions/cm2 at 723 K, and an in situ annealing experiment was carried out to monitor the evolution of helium bubbles during heating to 823 and 923 K. The pristine structure of FeCoNiCrTi0.2 samples and the evolution of helium bubbles during in situ annealing were both characterized by transmission electron microscopy. The annealing temperature and annealing time affect the process of helium bubbles evolution and formation. Meanwhile, the grain boundaries act as sinks to accumulate helium bubbles. However, the precipitation phase seems have few effects on the helium bubble evolution, which may be due to the coherent interface and same structure of γ' precipitation and matrix.

12.
Comput Intell Neurosci ; 2020: 1459107, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32802024

RESUMO

Computer vision is one of the hottest research fields in deep learning. The emergence of generative adversarial networks (GANs) provides a new method and model for computer vision. The idea of GANs using the game training method is superior to traditional machine learning algorithms in terms of feature learning and image generation. GANs are widely used not only in image generation and style transfer but also in the text, voice, video processing, and other fields. However, there are still some problems with GANs, such as model collapse and uncontrollable training. This paper deeply reviews the theoretical basis of GANs and surveys some recently developed GAN models, in comparison with traditional GAN models. The applications of GANs in computer vision include data enhancement, domain transfer, high-quality sample generation, and image restoration. The latest research progress of GANs in artificial intelligence (AI) based security attack and defense is introduced. The future development of GANs in computer vision is also discussed at the end of the paper with possible applications of AI in computer vision.


Assuntos
Biomimética , Computadores , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Visão Ocular , Expressão Facial , Humanos
13.
Org Biomol Chem ; 16(14): 2406-2410, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29565432

RESUMO

A visible-light-induced cascade Meerwein addition/cyclization of alkenes involving C-F bond cleavage was developed. This method offers a rapid access to azaspirocyclic cyclohexadienones from N-benzylacrylamides via C-F bond cleavage applying H2O as an external oxygen source, allowing for the incorporation of various aromatic moieties originating from aryldiazonium salts.

14.
Sensors (Basel) ; 16(2): 212, 2016 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-26861348

RESUMO

Due to their special environment, Underwater Wireless Sensor Networks (UWSNs) are usually deployed over a large sea area and the nodes are usually floating. This results in a lower beacon node distribution density, a longer time for localization, and more energy consumption. Currently most of the localization algorithms in this field do not pay enough consideration on the mobility of the nodes. In this paper, by analyzing the mobility patterns of water near the seashore, a localization method for UWSNs based on a Mobility Prediction and a Particle Swarm Optimization algorithm (MP-PSO) is proposed. In this method, the range-based PSO algorithm is used to locate the beacon nodes, and their velocities can be calculated. The velocity of an unknown node is calculated by using the spatial correlation of underwater object's mobility, and then their locations can be predicted. The range-based PSO algorithm may cause considerable energy consumption and its computation complexity is a little bit high, nevertheless the number of beacon nodes is relatively smaller, so the calculation for the large number of unknown nodes is succinct, and this method can obviously decrease the energy consumption and time cost of localizing these mobile nodes. The simulation results indicate that this method has higher localization accuracy and better localization coverage rate compared with some other widely used localization methods in this field.

15.
Sensors (Basel) ; 16(2): 170, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26840311

RESUMO

In many wireless sensor network application scenarios the key management scheme with a Mobile Sink (MS) should be fully investigated. This paper proposes a key management scheme based on dynamic clustering and optimal-routing choice of MS. The concept of Traveling Salesman Problem with Neighbor areas (TSPN) in dynamic clustering for data exchange is proposed, and the selection probability is used in MS route planning. The proposed scheme extends static key management to dynamic key management by considering the dynamic clustering and mobility of MSs, which can effectively balance the total energy consumption during the activities. Considering the different resources available to the member nodes and sink node, the session key between cluster head and MS is established by modified an ECC encryption with Diffie-Hellman key exchange (ECDH) algorithm and the session key between member node and cluster head is built with a binary symmetric polynomial. By analyzing the security of data storage, data transfer and the mechanism of dynamic key management, the proposed scheme has more advantages to help improve the resilience of the key management system of the network on the premise of satisfying higher connectivity and storage efficiency.

16.
Sensors (Basel) ; 15(12): 29958-69, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26633405

RESUMO

It is expected that in the near future wireless sensor network (WSNs) will be more widely used in the mobile environment, in applications such as Autonomous Underwater Vehicles (AUVs) for marine monitoring and mobile robots for environmental investigation. The sensor nodes' mobility can easily cause changes to the structure of a network topology, and lead to the decline in the amount of transmitted data, excessive energy consumption, and lack of security. To solve these problems, a kind of efficient Topology Control algorithm for node Mobility (TCM) is proposed. In the topology construction stage, an efficient clustering algorithm is adopted, which supports sensor node movement. It can ensure the balance of clustering, and reduce the energy consumption. In the topology maintenance stage, the digital signature authentication based on Error Correction Code (ECC) and the communication mechanism of soft handover are adopted. After verifying the legal identity of the mobile nodes, secure communications can be established, and this can increase the amount of data transmitted. Compared to some existing schemes, the proposed scheme has significant advantages regarding network topology stability, amounts of data transferred, lifetime and safety performance of the network.

17.
Opt Express ; 23(13): 17607-12, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26191768

RESUMO

We design and investigate a triple-band plasmonic metamaterial absorber (PMA) for sensor application. The underlying mechanism is investigated theoretically and numerically. Three characteristic absorption peaks are demonstrated to be induced by different plasmonic modes which lead to different responses for the plasmonic sensor. These modes show great improvement for the sensitivity and accuracy of the plasmonic sensors. This triple-band plasmonic metamaterial optical absorber has great potential to improve the performance in practical applications.

18.
Arch Pharm (Weinheim) ; 344(10): 689-95, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21887800

RESUMO

36 Novel heterocyclic chalcone derivatives were synthesized and tested for their anti-bacterial activity. Some compounds presented good anti-microbial activities against Gram-positive bacteria (including the multidrug-resistant clinical isolates). This class of compounds presented high potency against Streptococcus mutans, among which the derivatives F2 with an MIC of 2 µg/mL was as active as the standard drug (norfloxacin) and less active than oxacillin. All the compounds did not inhibit the growth of Gram-negative bacteria (Escherichia coli CCARM 1924 or Escherichia coli CCARM 1356) at 64 µg/mL.


Assuntos
Antibacterianos/síntese química , Chalcona/análogos & derivados , Chalcona/síntese química , Desenho de Fármacos , Furanos/química , Quinolinas/química , Compostos de Enxofre/química , Antibacterianos/química , Antibacterianos/farmacologia , Chalcona/química , Chalcona/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular
19.
Chem Biol Drug Des ; 77(1): 98-103, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21114630

RESUMO

In an attempt to search for more potent positive inotropic agents, a series of N-(4,5-dihydro-1-methyl-[1,2,4]triazolo[4,3-a]quinolin-7-yl)-2-(substitutedbenzyl-[1,4]diazepan-1-yl)acetamides were synthesized and evaluated for positive inotropic activity by measuring left atrium stroke volume in isolated rabbit heart preparations. Some of these derivatives exhibited favorable activity compared with the standard drug, milrinone, among which 2-(4-(4-methylbenzyl)-[1,4]-diazepan-1-yl)-N-(4,5-dihydro-1-methyl-[1,2,4]triazolo[4,3-a]quinolin-7-yl)acetamide (6m) was the most potent, increasing stroke volume by 8.38±0.16% (milrinone 2.45± 0.06%) at 3 x 10(-5) m. The chronotropic effects of those compounds having inotropic effects were also evaluated in this work.


Assuntos
Acetamidas , Azepinas/síntese química , Azepinas/farmacologia , Cardiotônicos , Coração/efeitos dos fármacos , Milrinona/farmacologia , Contração Miocárdica/efeitos dos fármacos , Volume Sistólico/efeitos dos fármacos , Triazóis/síntese química , Triazóis/farmacologia , Acetamidas/síntese química , Acetamidas/farmacologia , Animais , Cardiotônicos/síntese química , Cardiotônicos/farmacologia , Técnicas de Cultura de Órgãos/métodos , Coelhos
20.
Arch Pharm (Weinheim) ; 343(11-12): 700-5, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21110340

RESUMO

We describe the synthesis and positive inotropic evaluation of a series of 2-(4-substitutedbenzyl-1,4-diazepan-1-yl)-N-(4,5-dihydro-1-phenyl-[1,2,4]triazolo[4,3-a]quinolin-7-yl)acetamides by measuring left atrial stroke volume in preparations of isolated rabbit-heart. Several compounds were developed from, and showed favorable activities compared with the standard drug milrinone. Compound 5o was the most potent with an increased stroke volume of 9.17 ± 0.14% (milrinone 2.47 ± 0.08%) at 3 × 10⁻5 M in our in-vitro study. The chronotropic effects of those compounds having inotropic effects were also evaluated.


Assuntos
Acetamidas/síntese química , Cardiotônicos/síntese química , Coração/efeitos dos fármacos , Quinolinas/síntese química , Volume Sistólico/efeitos dos fármacos , Acetamidas/farmacologia , Animais , Frequência Cardíaca , Técnicas In Vitro , Quinolinas/farmacologia , Coelhos , Relação Estrutura-Atividade
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