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1.
Sci Rep ; 13(1): 23104, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38158438

RESUMO

With the rapid development of multimedia technology and the massive accumulation of user data, a huge amount of data is rapidly generated and shared over the network, while the problems of inappropriate data access and abuse persist. Reversible data hiding in encrypted images (RDHEI) is a privacy-preserving method that embeds protected data in an encrypted domain and accurately extracts the embedded data without affecting the original content. However, the amount of embedded data has been one of the major limitations in the performance and application of RDHEI. Currently, the main approaches to improve the capacity of RDHEI are either to increase the overall capacity or to reduce the length of the auxiliary information. In this paper, we propose a novel RDHEI scheme based on multi-prediction and adaptive Huffman encoding. To increase the overall capacity, we propose a multi-prediction, called MED+GAP predictor, to generate the label map data of non-reference pixels prior to image encryption. Then, an adaptive Huffman coding is designed to compress the generated labels in order to reduce the embedding length of the auxiliary information used for the extraction and recovery. Experiments show that the proposed method with MED+GAP predictor and adaptive Huffman coding improves 0.052 bpp, 0.023 bpp, and 0.047 bpp on average over the other state-of-the-art methods on the BOSSBase, BOWS-2, and UCID datasets, respectively, while maintaining security and reversibility.

2.
Biomed Chromatogr ; 36(12): e5483, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35975594

RESUMO

Aloin A/B and aloesin are the major bioactive constituents in Aloe vera, with diverse pharmacological activities, including anti-bacterial, anti-tumour, anti-inflammatory and intestinal regulation. However, the in vivo metabolism of aloin A/B and aloesin is still unclear. In this study, the metabolic processes of aloin A/B and aloesin in rats were investigated using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) and MetaboLynx™ software with the mass defect filter technique. Based on the proposed method, the prototype components of three compounds were all detected in rat plasma, urine and feces. Meanwhile, 25 aloin A/B metabolites (six phase I, three phase II, 16 phase I combined with phase II) and three aloesin metabolites (two phase I and one phase II) were detected in rats after oral administration of aloin A, aloin B and aloesin, and the main biotransformation reactions were hydroxylation, oxidation, methylation, acetylation and glucuronidation. In addition, aloin A and aloin B can be transformed into each other in vivo and the metabolic profiles of aloin A and aloin B are identical. These results provide essential data for further pharmaceutical research and clinical application of aloin A/B and aloesin.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Ratos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Ratos Sprague-Dawley
3.
J Pharm Biomed Anal ; 195: 113839, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33388645

RESUMO

The root and rhizome of Polygonum cuspidatum (Hu-Zhang) has been used for treatment of various inflammatory disorders in China. In our pervious study, we found that three fractions (HZE-30, HZE-60 and HZE-95) from the ethanol extract of Hu-Zhang (HZE) all could inhibit NO production, and HZE-60 shows the most potent anti-inflammatory activity. In order to understand the major contribution constituents of Hu-Zhang responsible for its anti-inflammatory effect, quantitative composition-activity relationship method was performed. Firstly, the constituents in HZE-60 were characterized using an ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) approach. Second, quantitative analyzed five major constituents identified in HZE-60 and compare the difference of five major constituents in HZE and three anti-inflammatory activity fractions. Finally, evaluated the anti-inflammatory effects of major constituents in lipopolysaccharide (LPS)-activated RAW264.7 macrophages. The results showed that a total of 31 compounds were identified from HZE-60, including 12 anthraquinones, 7 diphenylethenes, 9 phenols and 3 others. The contents of five major constituents (polydatin (6), resveratrol (7), emodin-1-O-ß-d-glucoside (15), emodin-8-O-ß-d-glucoside (21) and emodin (31)) were simultaneously determined by UPLC-PDA with good linearity (correlation coefficients > 0.9990) and satisfactory repeatability (RSD < 0.99 %), precision (RSD < 0.01 %), stability (RSD < 0.67 %) and recoveries (99.52 %-101.23 %, RSD < 0.91 %). All five major constituents could be detected in HZE and HZE-60 fraction, but only 6 was detected in HZE-30, and 31 in HZE-95. Moreover, 7, 15 and 21 exhibited significant anti-inflammatory activity via suppressing supernatant pro-inflammatory mediators, such as NO, tumor Necrosis Factor-α (TNF-α), interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1). Therefore, we conclude that the bioactivity of HZE is the syngeneic effect of its constituents, and 7, 15 and 21 should make great contributions for the anti-inflammatory effect of Hu-Zhang. The findings define the anti-inflammatory chemical constituents of Hu-Zhang, which will benefit further investigation on its quality control and the mechanism of action.


Assuntos
Fallopia japonica , Anti-Inflamatórios/farmacologia , China , Cromatografia Líquida de Alta Pressão , Lipopolissacarídeos , Macrófagos , Rizoma
4.
Neurosci Bull ; 37(4): 550-562, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33355900

RESUMO

Trigeminal neuropathic pain (TNP) is a significant health problem but the involved mechanism has not been completely elucidated. Toll-like receptors (TLRs) have recently been demonstrated to be expressed in the dorsal root ganglion and involved in chronic pain. Here, we show that TLR8 was persistently increased in the trigeminal ganglion (TG) neurons in model of TNP induced by partial infraorbital nerve ligation (pIONL). In addition, deletion or knockdown of Tlr8 in the TG attenuated pIONL-induced mechanical allodynia, reduced the activation of ERK and p38-MAPK, and decreased the expression of pro-inflammatory cytokines in the TG. Furthermore, intra-TG injection of the TLR8 agonist VTX-2337 induced pain hypersensitivity. VTX-2337 also increased the intracellular Ca2+ concentration, induced the activation of ERK and p38, and increased the expression of pro-inflammatory cytokines in the TG. These data indicate that TLR8 contributes to the maintenance of TNP through increasing MAPK-mediated neuroinflammation. Targeting TLR8 signaling may be effective for the treatment of TNP.


Assuntos
Neuralgia , Receptor 8 Toll-Like , Neuralgia do Trigêmeo , Animais , Hiperalgesia , Camundongos , Gânglio Trigeminal
5.
Int J Antimicrob Agents ; 52(1): 35-41, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29530588

RESUMO

Pseudomonas aeruginosa infection is a serious disease in cystic fibrosis patients and is difficult to treat owing to biofilm persistence and emerging multidrug resistance. Considering the essential role of quorum sensing (QS) in P. aeruginosa infections, the enhanced effects between the quorum sensing inhibitor (QSI) resveratrol and several antibiotics against P. aeruginosa PAO1 were investigated. Crystal violet staining assay revealed that biofilms of P. aeruginosa PAO1 grown in the presence of resveratrol were more susceptible to aminoglycoside antibiotics. Scanning electron and fluorescence microscopy showed architectural disruption of the biofilms when treated with resveratrol and aminoglycoside antibiotics. Furthermore, quantitative reverse transcription PCR (qRT-PCR) analysis demonstrated that expression of lasI and rhlI, two genes encoding enzymes that synthesise signal molecules in QS systems, were inhibited in the P. aeruginosa PAO1 biofilms by resveratrol. These results indicate that the QSI resveratrol can significantly enhance the effects of aminoglycoside antibiotics (e.g. tobramycin, gentamicin, amikacin and netilmicin) on P. aeruginosa PAO1 biofilms. These findings suggest that resveratrol is a potential accelerant in the treatment of P. aeruginosa biofilms and can restore or enhance the efficacy of aminoglycoside antibiotics.


Assuntos
Antibacterianos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Estilbenos/farmacologia , Aminoglicosídeos/farmacologia , Biofilmes/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Pseudomonas aeruginosa/fisiologia , Percepção de Quorum/genética , Resveratrol
6.
Bioorg Med Chem Lett ; 25(22): 5217-20, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26453007

RESUMO

Stilbenoids, known an important phytoalexins in plants, were renowned for their beneficial effects on cardiovascular, neurological and hepatic systems. In the present study, quorum sensing inhibition activity of ten stilbenoids were tested using Chromobacterium violaceum CV026 as the bio-indicator strain and the structure-activity relationship was also investigated. Among them, resveratrol (1), piceatannol (2) and oxyresveratrol (3) showed potential anti-QS activities. At the sub-MIC concentrations, 1-3 demonstrated a statistically significant reduction of violacein in C. violaceum CV026 in a concentration dependent manner. Furthermore, the effects of 1-3 on QS regulated virulence factors in Pseudomonas aeruginosa PAO1 were also evaluated. Our results showed that the stilbenoids 1-3 can markedly decreased the production of pyocyanin and swarming motility of P. aeruginosa PAO1. Further transcriptome analyses showed that 1-3 suppressed the expression of QS-induced genes: lasR, lasI, rhlR and rhlI.


Assuntos
Antibacterianos/farmacologia , Percepção de Quorum/efeitos dos fármacos , Estilbenos/farmacologia , Movimento Celular/efeitos dos fármacos , Chromobacterium/efeitos dos fármacos , Chromobacterium/genética , Genes Bacterianos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Piocianina/antagonistas & inibidores , Relação Estrutura-Atividade
7.
Huan Jing Ke Xue ; 36(10): 3641-8, 2015 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-26841595

RESUMO

In this study, we analyzed the stable hydrogen and oxygen isotope values of precipitation, soil water, irrigation water that collected in Shijiazhuang City from April 2013 to May 2014 to investigate the changing rule of the stable isotopes in different soil profiles and the process of soil water movement according to using the isotope tracer technique. The results showed that the mean excess deuterium of the local precipitation was -6.188 5 per thousand. Those reflected that the precipitation in Shijiazhuang City mainly brought by the monsoon from the ocean surface moisture, and also to some extent by the local evaporation. Precipitation was the main source of the soil water and the irrigation water played the supplementary role. In the rainy season, precipitation was enough to supply the soil water. The stable oxygen isotopes at 10-100 cm depth decreased with the increase of depth, the maximum depth of evaporation in the rainy season reached 40 cm. The peak of stable oxygen isotopes of soil water pushed down along the profile, which was infected by the interaction of the precipitation infiltration, evaporation and the mixing water.


Assuntos
Solo , Movimentos da Água , Água/química , Irrigação Agrícola , China , Cidades , Deutério/análise , Isótopos de Oxigênio/análise , Chuva , Estações do Ano
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