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1.
Sensors (Basel) ; 24(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38931702

RESUMO

To tackle the intricate challenges associated with the low detection accuracy of images taken by unmanned aerial vehicles (UAVs), arising from the diverse sizes and types of objects coupled with limited feature information, we present the SRE-YOLOv8 as an advanced method. Our method enhances the YOLOv8 object detection algorithm by leveraging the Swin Transformer and a lightweight residual feature pyramid network (RE-FPN) structure. Firstly, we introduce an optimized Swin Transformer module into the backbone network to preserve ample global contextual information during feature extraction and to extract a broader spectrum of features using self-attention mechanisms. Subsequently, we integrate a Residual Feature Augmentation (RFA) module and a lightweight attention mechanism named ECA, thereby transforming the original FPN structure to RE-FPN, intensifying the network's emphasis on critical features. Additionally, an SOD (small object detection) layer is incorporated to enhance the network's ability to recognize the spatial information of the model, thus augmenting accuracy in detecting small objects. Finally, we employ a Dynamic Head equipped with multiple attention mechanisms in the object detection head to enhance its performance in identifying low-resolution targets amidst complex backgrounds. Experimental evaluation conducted on the VisDrone2021 dataset reveals a significant advancement, showcasing an impressive 9.2% enhancement over the original YOLOv8 algorithm.

2.
J Pharm Biomed Anal ; 239: 115883, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38044218

RESUMO

Colon cancer is associated with a high mortality rate. Vincristine (VCR) is a commonly used chemotherapeutic drug. Celastrol (CEL) is an effective component which exerts inhibitory effects on colon cancer. Combination treatment improves resistance to chemotherapeutic drugs and enhances their efficacy. Therefore, we aimed to explore the molecular mechanisms of VCR combined with CEL in colon cancer treatment. We verified the effects of VCR combined with CEL on the proliferation, cell cycle, and apoptosis of HCT-8 cells. Non-targeted metabolomic techniques were used to analyse the changes in cellular metabolites after administration. Finally, network pharmacology technology was used to screen the potential targets and pathways. VCR combined with CEL had synergistic inhibitory effects on HCT-8 colon cancer cells. Cell metabolomics identified 12 metabolites enriched in metabolic pathways, such as the phenylalanine, tyrosine and tryptophan biosynthesis pathways. Network pharmacology revealed that MAPK1, AKT1, PIK3CB, EGFR, and VEGFA were the key targets. Western blotting revealed that VCR combined with CEL activated the P53 pathway by suppressing the PI3K/AKT signalling pathway activation and Bcl-2 expression, promoting the Bax expression. Therefore, VCR combined with CEL potentially treats colon cancer by increasing the apoptosis, improving energy metabolism, and inhibiting PI3K/AKT pathway in colon cancer cells.


Assuntos
Neoplasias do Colo , Proteínas Proto-Oncogênicas c-akt , Humanos , Vincristina/farmacologia , Vincristina/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/uso terapêutico , Farmacologia em Rede , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Metabolômica
3.
Clin Pharmacol Drug Dev ; 13(2): 140-145, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37743573

RESUMO

This trial was a randomized, open-label, single-dose, 2-treatment, 2-period, crossover study to evaluate the pharmacokinetic (PK) profile, bioequivalence, and safety of test formulation and reference formulation of 2-mg dienogest tablets in healthy Chinese participants. Eligible participants were randomly administered a single 2-mg dose of either the test formulation or the reference formulation orally under fed conditions, followed by a 1-week washout period and the administration of the other formulation. Samples of blood were collected until 48 hours following administration. The main PK parameters were calculated using noncompartmental analysis techniques. The main PK parameters included maximum plasma concentration, area under the plasma concentration-time curve (AUC) from time zero to the last quantifiable concentration, and AUC from time zero to infinity. The bioequivalence of test and reference dienogest tablets was determined if the 90% confidence intervals of the geometric mean ratio of the test to reference formulations were within the predefined range of 80%-125%. The safety assessment included incidence of adverse events and serious adverse events and others. Twenty-four healthy Chinese participants were enrolled in this trial. The geometric mean ratios of maximum plasma concentration, AUC from time zero to the last quantifiable concentration, and AUC from time zero to infinity between the 2 formulations, and corresponding 90% confidence intervals, all fell within the range of 80%-125% under fed conditions. The test and reference dienogest tablets were well tolerated, and no severe adverse events were reported in the trial. It was shown that the test and the reference dienogest tablets were bioequivalent and well tolerated under fed conditions in healthy Chinese female participants.


Assuntos
Nandrolona/análogos & derivados , Equivalência Terapêutica , Humanos , Feminino , Disponibilidade Biológica , Estudos Cross-Over , China
4.
Chem Commun (Camb) ; 58(57): 7944-7947, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35748882

RESUMO

A novel single-solvent-interfacial strategy is proposed to synthesize hollow MOFs, fabricated at the two-phase interface originated from the self-deliquescence of hydration water in the metallic precursors and the solvents with low water solubility. The as-fabricated HMOFs with hierarchically porous structures exhibit significant enhancement in CO2 separation and catalysis.

5.
Chem Commun (Camb) ; 58(9): 1422-1425, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35001097

RESUMO

A novel two-dimensional ZIF-derived Pd@CN material prepared via one-step calcination exhibits outstanding catalytic activity in heterogeneous hydrogenation. Its well-developed porous structure, low dimensions and low density make active sites more accessible. This facile and effective strategy can guide the synthesis of highly active and durable Pd@CN catalysts with specific morphologies.

6.
Sensors (Basel) ; 20(19)2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32998316

RESUMO

Visual-based object detection and understanding is an important problem in computer vision and signal processing. Due to their advantages of high mobility and easy deployment, unmanned aerial vehicles (UAV) have become a flexible monitoring platform in recent years. However, visible-light-based methods are often greatly influenced by the environment. As a result, a single type of feature derived from aerial monitoring videos is often insufficient to characterize variations among different abnormal crowd behaviors. To address this, we propose combining two types of features to better represent behavior, namely, multitask cascading CNN (MC-CNN) and multiscale infrared optical flow (MIR-OF), capturing both crowd density and average speed and the appearances of the crowd behaviors, respectively. First, an infrared (IR) camera and Nvidia Jetson TX1 were chosen as an infrared vision system. Since there are no published infrared-based aerial abnormal-behavior datasets, we provide a new infrared aerial dataset named the IR-flying dataset, which includes sample pictures and videos in different scenes of public areas. Second, MC-CNN was used to estimate the crowd density. Third, MIR-OF was designed to characterize the average speed of crowd. Finally, considering two typical abnormal crowd behaviors of crowd aggregating and crowd escaping, the experimental results show that the monitoring UAV system can detect abnormal crowd behaviors in public areas effectively.

7.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(4): 2347-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-25856518

RESUMO

The complete chloroplast genome of Andrographis paniculata, an important medicinal plant with great economic value, has been studied in this article. The genome size is 150,249 bp in length, with 38.3% GC content. A pair of inverted repeats (IRs, 25,300 bp) are separated by a large single copy region (LSC, 82,459 bp) and a small single-copy region (SSC, 17,190 bp). The chloroplast genome contains 114 unique genes, 80 protein-coding genes, 30 tRNA genes and 4 rRNA genes. In these genes, 15 genes contained 1 intron and 3 genes comprised of 2 introns.


Assuntos
Andrographis/classificação , Andrographis/genética , Genoma de Cloroplastos , Plantas Medicinais/classificação , Plantas Medicinais/genética , Sequenciamento Completo do Genoma , Genes de Plantas , Tamanho do Genoma , Fases de Leitura Aberta , Filogenia , Análise de Sequência de DNA
8.
Zhong Yao Cai ; 37(2): 219-23, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-25095339

RESUMO

OBJECTIVE: To establish the high-performance thin layer chromatography (HPTLC) fingerprint of andrographolides from Andrographis paniculata, and to valuate the fingerprint similarity of samples from different habitats, markets, used parts and so on. METHODS: Chromatographic conditions were as follows: stationary phase: precoated HPTLC GF254 silica-gel plate (20 cm x 10 cm); developing solvent system: chloroform-toluene-methanol (80:10:15); Relative humidity: 42%; Color development reagent: 5% H2SO4 ethanolic solution, heating at 105 degrees C and observing the fluorescent chromatogram in a UV cabinet at 366 nm. The common patterns of HPTLC fingerprint were obtained through CHROMAP 1.5 solution software. RESULTS: The HPTLC fingerprint of andrographolides was consisted of 9 characteristic peaks (fluorescent bands) including andrographolide, neoandrographolide and dehydroandrographolide which were chemical reference substances. The investigation and analysis of 51 batches of Andrographis paniculata showed that there were remarkable differences among different samples, so was the content of andrographolide and total lactones. CONCLUSION: This method is simple and rapid, which can serve as an effective identification and quality assessment method for Andrographis paniculata.


Assuntos
Andrographis/química , Cromatografia Líquida de Alta Pressão/métodos , Diterpenos/química , Plantas Medicinais/química , Andrographis/crescimento & desenvolvimento , Cromatografia em Camada Fina , Dessecação/métodos , Estabilidade de Medicamentos , Glucosídeos/química , Componentes Aéreos da Planta/química , Plantas Medicinais/crescimento & desenvolvimento , Tetra-Hidronaftalenos/química
9.
Rev Sci Instrum ; 83(7): 075112, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22852729

RESUMO

In this paper, a compact, low jitter, nanosecond rise time, command triggered, high peak power, gas-switch pulse generator system is developed for high energy physics experiment. The main components of the system are a high voltage capacitor, the spark gap switch and R = 50 Ω load resistance built into a structure to obtain a fast high power pulse. The pulse drive unit, comprised of a vacuum planar triode and a stack of avalanche transistors, is command triggered by a single or multiple TTL (transistor-transistor logic) level pulses generated by a trigger pulse control unit implemented using the 555 timer circuit. The control unit also accepts user input TTL trigger signal. The vacuum planar triode in the pulse driving unit that close the first stage switches is applied to drive the spark gap reducing jitter. By adjusting the charge voltage of a high voltage capacitor charging power supply, the pulse amplitude varies from 5 kV to 10 kV, with a rise time of <3 ns and the maximum peak current up to 200 A (into 50 Ω). The jitter of the pulse generator system is less than 1 ns. The maximum pulse repetition rate is set at 10 Hz that limited only by the gas-switch and available capacitor recovery time.

10.
Zhonghua Gan Zang Bing Za Zhi ; 14(7): 514-6, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16867273

RESUMO

OBJECTIVES: To explore the mechanism of CBRH-7919 cell proliferation inhibition by transfecting phosphatidylethanolamine N-methyltransferase 2 gene (PEMT2). METHODS: The effects of PEMT2 transfection on phosphorylation and translocation from cytosol to plasma membrane of PLC gamma 1 in cells were studied using SDS-PAGE and Western blot techniques. The phosphorylation and activity of c-Met were determined. RESULTS: After transfection of pemt2, the PLC gamma 1 and phosphorylated PLC gamma 1 conjugated with plasma membrane were decreased by 45% and 27% of that of control cells respectively, and the phosphorylated c-Met was decreased to 32% of that of control cells. CONCLUSION: Transfection of phosphatidylethanolamine N-methyltransferase 2 gene can inhibit the phosphorylation and translocation from cytosol to plasma membrane of PLC gamma 1 in cells. At the same time, the autophosphorylation of c-Met was decreased, which suggests that transfection of phosphatidylethanolamine N-methyltransferase 2 gene can downregulate the c-Met/PLC gamma 1 signaling pathway in CBRH-7919 cells.


Assuntos
Proliferação de Células , Fosfatidiletanolamina N-Metiltransferase/genética , Fosfolipase C gama/genética , Animais , Linhagem Celular Tumoral , Movimento Celular , Neoplasias Hepáticas Experimentais , Fosfatidiletanolamina N-Metiltransferase/metabolismo , Fosfolipase C gama/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-met/metabolismo , Ratos , Transfecção
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