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1.
Nat Commun ; 15(1): 6015, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39019876

RESUMEN

Cutting-edge mid-wavelength infrared (MWIR) sensing technologies leverage infrared photodetectors, memory units, and computing units to enhance machine vision. Real-time processing and decision-making challenges emerge with the increasing number of intelligent pixels. However, current operations are limited to in-sensor computing capabilities for near-infrared technology, and high-performance MWIR detectors for multi-state switching functions are lacking. Here, we demonstrate a non-volatile MoS2/black phosphorus (BP) heterojunction MWIR photovoltaic detector featuring a semi-floating gate structure design, integrating near- to mid-infrared photodetection, memory and computing (PMC) functionalities. The PMC device exhibits the property of being able to store a stable responsivity, which varies linearly with the stored conductance state. Significantly, device weights (stable responsivity) can be programmed with power consumption as low as 1.8 fJ, and the blackbody peak responsivity can reach 1.68 A/W for the MWIR band. In the simulation of Faster Region with convolution neural network (CNN) based on the FLIR dataset, the PMC hardware responsivity weights can reach 89% mean Average Precision index of the feature extraction network software weights. This MWIR photovoltaic detector, with its versatile functionalities, holds significant promise for applications in advanced infrared object detection and recognition systems.

2.
Nat Commun ; 15(1): 1613, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38383735

RESUMEN

In-sensor processing has the potential to reduce the energy consumption and hardware complexity of motion detection and recognition. However, the state-of-the-art all-in-one array integration technologies with simultaneous broadband spectrum image capture (sensory), image memory (storage) and image processing (computation) functions are still insufficient. Here, macroscale (2 × 2 mm2) integration of a rippled-assisted optoelectronic array (18 × 18 pixels) for all-day motion detection and recognition. The rippled-assisted optoelectronic array exhibits remarkable uniformity in the memory window, optically stimulated non-volatile positive and negative photoconductance. Importantly, the array achieves an extensive optical storage dynamic range exceeding 106, and exceptionally high room-temperature mobility up to 406.7 cm2 V-1 s-1, four times higher than the International Roadmap for Device and Systems 2028 target. Additionally, the spectral range of each rippled-assisted optoelectronic processor covers visible to near-infrared (405 nm-940 nm), achieving function of motion detection and recognition.

3.
PeerJ Comput Sci ; 9: e1674, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38077550

RESUMEN

Software-defined networking (SDN) faces many of the same security threats as traditional networks. The separation of the SDN control plane and data plane makes the controller more vulnerable to cyber attacks. The conventional "perimeter defense" network security model cannot prevent lateral movement attacks caused by malicious insider users or hardware and software vulnerabilities. The "zero trust architecture" has become a new security network model to protect enterprise network security. In this article, we propose an intelligent zero-trust security framework IZTSDN for the software-defined networking by integrating deep learning and zero-trust architecture, which adopts zero-trust architecture to protect every resource and network connection in the network. IZTSDN uses a traffic anomaly detection mode CALSeq2Seql based on a deep learning algorithm to analyze users' network behavior in real-time and achieve continuous tracking and analysis of users, restrict malicious users from accessing network resources, and realize the dynamic authorization process. Finally, the Mininet simulation platform is extended to build the simulation platform MiniIZTA supporting zero-trust architecture and the proposed security framework IZTSDN is experimentally analyzed. The experimental results show that the IZTSDN security framework can provide about 80.5% of throughput when the network is attacked. The accuracy of abnormal traffic detection reaches 99.56% on the SDN dataset, which verifies that the reliability and availability of the IZTSDN security framework are verified.

4.
Comput Methods Biomech Biomed Engin ; 26(7): 835-845, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35758223

RESUMEN

The injury conditions of the sitting position occupant inside the military equipment are highly related to the vertical impact environments. In this study, a detailed three-dimensional finite element (FE) model of pelvis-lumbar spine of seated human with nonlinear material property and strain failure criterion was developed and validated. A series of sinusoidal accelerations with a constant peak speed of 8 m/s and frequencies ranging from 10 Hz to 90 Hz were loaded on the FE model to investigate the injury conditions under different high loading rates. The results indicated that the injury patterns mainly include wedge fracture of the junction between lumbar spine and pelvis, and comminuted fracture of ischial tuberosity. The bending moment caused by the large angle deflection of pelvis under 10 Hz case (low rate) and the acting force caused by the excessive curvature of lumbar spine under 30 Hz-70 Hz cases (medium and high rate) cause the junction wedge fractured, while the high impact force under 30 Hz-50 Hz cases (medium rate) leads to comminuted fracture of the ischial tuberosity. The associated mechanism that the shorter the time interval between the peak of seat loading speed and the peak of hip muscle compression, the more serious dynamic responses of pelvis-lumbar spine is revealed for the first time.


Asunto(s)
Fracturas Conminutas , Sedestación , Humanos , Análisis de Elementos Finitos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/fisiología , Postura/fisiología , Pelvis
5.
Mater Horiz ; 9(3): 1036-1044, 2022 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-35022629

RESUMEN

Phase engineering of two-dimensional transition metal dichalcogenides has received increasing attention in recent years due to its atomically thin nature and polymorphism. Here, we first realize an electric-field-induced controllable phase transition between semiconducting 2H and metallic 1T' phases in MoTe2 memristive devices. The device performs stable bipolar resistive switching with a cycling endurance of over 105, an excellent retention characteristic of over 105 s at an elevated temperature of 85 °C and an ultrafast switching of ∼5 ns for SET and ∼10 ns for RESET. More importantly, the device works in different atmospheres including air, vacuum and oxygen, and even works with no degradation after being placed in air for one year, indicating excellent surrounding and time stability. In situ Raman analysis reveals that the stable resistive switching originates from a controllable phase transition between 2H and 1T' phases. Density functional theory calculations reveal that the Te vacancy facilitates the phase transition in MoTe2 through decreasing the barrier between 2H and 1T' phases, and serving as nucleation sites due to the elimination of repulsive forces. This electric-field-induced controllable phase transition in MoTe2 devices offers new opportunities for developing reliable and ultrafast phase transition devices based on atomically thin membranes.

6.
Huan Jing Ke Xue ; 43(1): 277-284, 2022 Jan 08.
Artículo en Chino | MEDLINE | ID: mdl-34989512

RESUMEN

In this study, we separately collected rainwater sewer sediments from typical samples in Suzhou city, such as the urban commercial district, historical and cultural protection area, cultural and educational area, and living area, and analyzed the particle size distribution of the sediments and the characteristics of carbon, nitrogen, phosphorus content, and pollution load distribution under each graded particle size. The median particle size D50 of each sample point was 16.55-327.50 µm, and the particle size trend was as follows:commercial area > living area > historical and cultural protection area > cultural and educational area. D50 was related to the total organic carbon (TOC). The total nitrogen (TN), total phosphorus (TP), and ammonia nitrogen (NH4+-N) were significantly positively correlated, as were the pollutants. The spatial difference of ω(TOC), ω(TN), ω(TP), and ω(NH4+-N) in rainwater sewer sediments from different regions was as follows:commercial area > historical and cultural protection area > living area > cultural and educational area, in which ω(TOC) was 0.84%-6.76%, and ω(TN), ω(TP), and ω(NH4+-N) were 917.5-12707.1, 196.1-2524.8, and 9.3-156.8 mg·kg-1, respectively. TOC, TP, and NH4+-N pollution loads were mainly concentrated on particles ≤ 75 µm and 250-1000 µm. Street dust pollutants highly differed spatially, with a high content of attached pollutants on street dust particles with a particle size of ≤ 75 µm. Various pollutants migrated into the street dust-pipes, and TP and TN showed certain enrichment characteristics in the sewer. Controlling the transportation of street dust and the accumulation of sediments in the sewer can reduce the pollution of sediment into the rivers during the rainy season.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Nitrógeno/análisis , Fósforo/análisis , Contaminantes Químicos del Agua/análisis
8.
Mol Plant Pathol ; 22(12): 1624-1640, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34498365

RESUMEN

The priming of defence responses in pathogen-challenged model plants undergoes a preparation phase and an expression phase for defence function. However, the priming response in postharvest fruits has not been elucidated. Here, we found that 50 mM ß-aminobutyric acid (BABA) treatment could induce two distinct pathways linked with TGA1-related systemic acquired resistance (SAR), resulting in the alleviation of Rhizopus rot in postharvest peach fruit. The first priming phase was elicited by BABA alone, leading to the enhanced transcription of redox-regulated genes and posttranslational modification of PpTGA1. The second phase was activated by an H2 O2 burst via up-regulation of PpRBOH genes and stimulation of the MAPK cascade on pathogen invasion, resulting in a robust defence. In the MAPK cascade, PpMAPKK5 was identified as a shortcut interacting protein of PpTGA1 and increased the DNA binding activity of PpTGA1 for the activation of salicylic acid (SA)-responsive PR genes. The overexpression of PpMAPKK5 in Arabidopsis caused the constitutive transcription of SA-dependent PR genes and as a result conferred resistance against the fungus Rhizopus stolonifer. Hence, we suggest that the BABA-induced priming defence in peaches is activated by redox homeostasis with an elicitor-induced reductive signalling and a pathogen-stimulated H2 O2 burst, which is accompanied by the possible phosphorylation of PpTGA1 by PpMAPKK5 for signal amplification.


Asunto(s)
Prunus persica , Aminobutiratos , Frutas , Homeostasis , Oxidación-Reducción , Enfermedades de las Plantas , Ácido Salicílico/farmacología
9.
J Biomech ; 127: 110666, 2021 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-34371474

RESUMEN

Underwater explosion (UNDEX) can cause severe damage to hull structure, equipment and human. In this paper, the effect of UNDEX load, including shock wave and bubble pulsation, on seated human response was investigated. The incident pressure of non-contact UNDEX was calculated. A lumped parameter interaction model of the ship structure (single-deck and multi-deck) and seated human was created based on the Taylor's theory and its veracity was verified. The results indicated that the pelvis, which is in direct contact with the structure, is the most vulnerable part of seated human when suffered impact. The shock wave and bubble pulsation had equal destructive potential to upper torso, viscera and head. The low pass filtering feature of multi-deck configuration may magnify the human response caused by the upper deck motion. The energy carried by the low and high frequency component was the dominant factors to human injury and the broadband protection to human shock isolation design is essential.


Asunto(s)
Navíos , Sedestación , Humanos , Movimiento (Física) , Sujetos de Investigación , Torso
10.
Front Plant Sci ; 12: 646147, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33763101

RESUMEN

Although heat shock proteins (HSPs), a family of ubiquitous molecular chaperones, are well characterized in heat stress-related responses, their function in plant defense remains largely unclear. Here, we report the role of VvHSP24, a class B HSP from Vitis vinifera, in ß-aminobutyric acid (BABA)-induced priming defense against the necrotrophic fungus Botrytis cinerea in grapes. Grapes treated with 10 mmol L-1 BABA exhibited transiently increased transcript levels of VvNPR1 and several SA-inducible genes, including PR1, PR2, and PR5. Additionally, phytoalexins accumulated upon inoculation with the gray mold fungus B. cinerea, which coincided with the action of a priming mode implicated in pathogen-driven resistance. Intriguingly, electrophoretic mobility shift (EMSA), yeast two-hybrid (Y2H) and His pull-down assays demonstrated that the nuclear chaperone VvHSP24 cannot modulate the transcript of PR genes but does directly interact with VvNPR1 in vivo or in vitro. Furthermore, we found that VvHSP24 overexpression enhanced the transcript levels of NPR1 and SA-responsive genes (PR1, PR2, and PR5) and increased the resistance of transgenic Arabidopsis thaliana to B. cinerea compared with wildtype Col-0. An opposite trend between CRISPR mutants of AtHSFB1 (the orthologous gene of VvHSP24 in Arabidopsis) and wildtype plants was observed. Hence, our results suggest that VvHSP24 has a potential role in NPR1-dependent plant resistance to fungal pathogen. BABA-induced priming defense in grapes may require posttranslational modification of the chaperone VvHSP24 to activate VvNPR1 transcript, leading to PR gene expressions and resistance phenotypes.

11.
Plant Physiol Biochem ; 156: 552-565, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33059266

RESUMEN

Either NPR1 or TGA1 serve as master redox-sensitive transcriptional regulators for the transcription of PR genes in plants. The redox modification of the two co-activators involved in BABA-induced priming resistance against Botrytis cinerea in grapes was examined in this study. The results showed that 10 mmol L-1 BABA could effectively trigger a priming defense in grapes as manifested by augmented expression levels of PR genes upon inoculation with B. cinerea. Moreover, transcriptome profiling analysis revealed that all of the sets of key genes in the enzymatic ROS scavenging system, the PPP and AsA-GSH cycle were in harmony and were transcriptionally induced in BABA-primed grapes with pathogenic infection; in addition, this enhanced expression caused the accelerated accumulation of reductive substances, namely, AsA, GSH and NADPH, resulting in reduced intercellular conditions. Under reduced conditions, the interaction of VvTGA1 and VvNPR1 in the Y2H assay implied that VvTGA1 can provide the DNA binding capacity required by VvNPR1 for activation of VvPR genes. Consequently, the transactivation of VvNPR1 by the promoters of VvPR1, VvPR2 and VvPR5 was determined via a DLR assay, and it induced the transcription of the VvPR genes. In parallel, the redox-modified reducing condition achieved with an abundant supply of reductive substances was closely associated with the translocation of NPR1 for interaction with TGA in the nucleus. Thus, the posttranslational modification and subsequent interaction of the two redox-sensitive co-activators of VvNPR1 and VvTGA1 under reduced conditions may be responsible for BABA-induced priming for effective disease resistance in grapes.


Asunto(s)
Aminobutiratos/farmacología , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/fisiología , Botrytis/patogenicidad , Citrus paradisi/microbiología , Enfermedades de las Plantas/prevención & control , Proteínas de Plantas/fisiología , Resistencia a la Enfermedad , Humanos , Oxidación-Reducción , Enfermedades de las Plantas/microbiología
12.
ACS Appl Mater Interfaces ; 11(35): 32423-32430, 2019 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-31409064

RESUMEN

Solvent freezing is an important method to produce polymer foams with highly tunable pore structure. However, foams prepared from aqueous solution precursors commonly suffer from poor water resistance, whereas those organo-phase systems are not environmental friendly. Here, we present that using an emulsion lyophilization method can overcome such a contradiction and synthesize multifunctional polymer foams. Commercially available polyacrylate-based emulsions with various targeted glass transition temperatures (Tgs) were applied. Adipodihydrazide molecules contained in the water phase of the emulsions reacted with the acetyl groups on the polymers during the freeze-drying, forming elastic networks to maintain the pore structure. The foams can tolerate a 650% elongation without failure and are notch insensitive. The porosity of the foams can be tuned from approximately 45 to 90% via lyophilization of diluted emulsions. The facile blending of emulsions with different targeted Tgs enabled foams with multishape memory capability. Moreover, the foams showed an excellent mechanical damping property, and the slow recovery nature enabled a clip application of clamping extremely weak objects.

13.
Clin Exp Hypertens ; 38(4): 393-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27159544

RESUMEN

The endothelium contributes to the maintenance of vasodilator tone by releasing nitric oxide (NO), prostacyclin (PGI2), and endothelium-derived hyperpolarizing factor (EDHF). In hypertension, endothelium-dependent relaxation is attenuated (a phenomenon referred to as endothelial dysfunction) and contributes to the increased peripheral resistance. However, which vasodilator among NO, PGI2, and EDHF is impaired in hypertension remains largely unknown. The present study was designed to study the exact contribution of NO, PGI2, and EDHF to vascular reactivity in conduit and resistance artery, under physiological and pathological conditions. The aorta and the second-order mesenteric artery from spontaneous hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats were used to measure the vasorelaxation with myograph technology, in the presence or absence of different inhibitors. The results showed that the endothelium-dependent vasodilatation in the conduit artery was mediated mainly by NO, whereas the resistant artery by NO, PGI2, and EDHF together. In hypertension, both NO-mediated relaxation in the conduit artery and NO-, PGI2-, and EDHF-mediated dilation in the resistant artery were markedly impaired. Furthermore, the endothelium-dependent and the endothelium-independent vasorelaxation in conduit artery was attenuated more pronouncedly than that in the resistant artery from hypertensive rats, suggesting that the conduit artery is more vulnerable to hypertensive condition. In conclusion, vasodilators including NO, PGI2, and EDHF contribute distinctively to endothelium-dependent relaxation in conduit and resistance artery under physiological and pathological conditions.


Asunto(s)
Factores Biológicos/metabolismo , Endotelio Vascular , Hipertensión , Animales , Endotelio Vascular/metabolismo , Endotelio Vascular/fisiopatología , Factores Relajantes Endotelio-Dependientes/metabolismo , Epoprostenol/metabolismo , Hipertensión/metabolismo , Hipertensión/fisiopatología , Masculino , Arterias Mesentéricas/efectos de los fármacos , Modelos Cardiovasculares , Óxido Nítrico/metabolismo , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Resistencia Vascular/fisiología , Vasodilatación/fisiología
14.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 35(4): 481-7, 2015 Apr.
Artículo en Chino | MEDLINE | ID: mdl-26043575

RESUMEN

OJECTIVE: To observe the effect of tianma gouteng decoction (TGD) on the endothelial function and the renal protein expression of spontaneously hypertensive rats, and to analyze its possible mechanism. METHODS: Totally 18 6-week-old SHR were randomly divided into 3 groups according to randomized block design, the SHR control group, the TGD group, and the captopril group, 6 in each group. Meanwhile, Wistar Kyoto (WKY) rats of the same age were recruited as a WKY control group. Rats in the TGD group were administered with TGD at the daily dose of 10. 260 g/kg. Rats in the captopril group were administered with captopril at the daily dose of 3. 375 g/kg. 2 mL/100 g distilled water was administered to rats in the SHR control group and the WKY control group. All medication was performed by gastrogavage once per day till rats were 24 weeks old. Changes of blood pressure were measured once per two weeks. The relaxation of the thoracic aorta and the superior mesenteric artery was determined by vascular ring in vitro to reflect the endothelial function. The total renal protein was separated by two-dimensional electrophoresis (2-DE). The significantly deviated protein was verified by Western blot. RESULTS: (1) Compared with the SHR control group, blood pressure was significantly lowered in rats (10 - 24 weeks old) of the captopril group (P <0.01, P <0.05). The hypotensive effect of TGD was obvious at the beginning of hypertension (10 -12 weeks) (P <0. 01). But along with the progression of hypertension, its hypotensive effect was not obvious (P>0. 05). (2) Compared with the SHR control group, the relaxation of the superior mesenteric artery was obviously improved in the TGD group (P <0. 05); the relaxation of the thoracic aorta and the superior mesenteric artery was obviously superior in the WKY control group (P <0. 01, P <0. 05). But there was no statistical difference in each relaxation index between the captopril group and the SHR control group (P >0. 05).(3) RESULTS: of 2-DE found 16 significantly differential renal protein, mainly involved nitric oxide (NO) system, oxidative stress, and cytoskeleton-related proteins. Results of Western blot showed that TGD could significantly improve expressions of Cu-Zn superoxide dismutase (SOD), N(G, N(G)-dimethylarginine dimethylaminohydrolase 2 (DDAH2), and pterin-4-alpha-carbinolamine dehydratase 1 (PCBD1) (P <0. 05). CONCLUSION: GTD could protect the endothelial function of the superior mesenteric artery in SHR, and its intervention mechanism of hypertension induced early renal injury might be relevant to regulating the NO system and antioxidative stress.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Hipertensión/tratamiento farmacológico , Riñón/metabolismo , Animales , Presión Sanguínea , Captopril , Estrés Oxidativo , Proteínas/metabolismo , Proteómica , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Superóxido Dismutasa/metabolismo
15.
Zhong Yao Cai ; 37(5): 833-40, 2014 May.
Artículo en Chino | MEDLINE | ID: mdl-25335292

RESUMEN

OBJECTIVE: To observe the differential protein expression profile of three different Chinese medicine compounds on spontaneous hypertensive rat, which were Banxiabaizhutianma Decoction, Dihuangyinzi Decoction and Tianmagouteng Decoction, and to elaborate their function characters and regulation pathway using the principal component analysis and analyze the basic theory of different treatment of hypertension. METHODS: Give three compounds to 6-week-old SHR (Spontaneous hypertensive rat) as experimental group and captopril to 6-week-old WKY (Wistar-Kyoto rat) as control group by gavage. Monitor the blood pressure of rat tail to 24-week-old and then all rats were decapitated. Extracte the rental protein to finish two-dimensional electrophoresis experiments and get the differential protein spots using PDQuest software. Study the three different compounds' effect of trend on SHR blood pressure using PCAC principal component analysis. RESULTS: The blood pressure of SHR remained rising from 6-week-old to 10-week-old, when Tianmagouteng Decoction had a significant anti-hypertension effect. But as the blood pressure of SHR remained high, Banxiabaizhutianma Decoction and Dihuangyinzi Decoction performed better in lowering blood pressure. At last, renal protein expression profile analysis showed that there were 84 significantly different proteins between SHR and WKY of 24-week-old and the PCA result showed that the principal component extraction was 95.951%, it was sure that Tianmagouteng Decoction and Banxiabaizhutianma Decoction had significantly changed rental protein spots on SHR while Dihuangyinzi Decoction had not. CONCLUSION: In the early stages of rising blood pressure, Tianmagouteng Decoction has significant anti-hypertensive effect. But when the blood pressure remain high, Banxiabaizhutianma Decoction and Dihuangyinzi Decoction are superior to Tanmagouteng Decoction in anti-hypertension. Banxiabaizhutianma Decoction and Tianmagouteng Decoction can significantly improve rental protein spots on SHR while Dihuangyinzi Decoction can not.


Asunto(s)
Antihipertensivos/farmacología , Medicamentos Herbarios Chinos/farmacología , Hipertensión/tratamiento farmacológico , Riñón/metabolismo , Proteínas/metabolismo , Proteómica , Animales , Antihipertensivos/uso terapéutico , Presión Sanguínea/efectos de los fármacos , Combinación de Medicamentos , Medicamentos Herbarios Chinos/uso terapéutico , Electroforesis en Gel Bidimensional , Hipertensión/metabolismo , Hipertensión/patología , Riñón/patología , Masculino , Plantas Medicinales/química , Análisis de Componente Principal , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY
16.
PLoS One ; 9(6): e99697, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24927178

RESUMEN

Korean mondshood root polysaccharides (KMPS) isolated from the root of Aconitum coreanum (Lévl.) Rapaics have shown anti-inflammatory activity, which is strongly influenced by their chemical structures and chain conformations. However, the mechanisms of the anti-inflammatory effect by these polysaccharides have yet to be elucidated. A RG-II polysaccharide (KMPS-2E, Mw 84.8 kDa) was isolated from KMPS and its chemical structure was characterized by FT-IR and NMR spectroscopy, gas chromatography-mass spectrometry and high-performance liquid chromatography. The backbone of KMPS-2E consisted of units of [→6) -ß-D-Galp (1→3)-ß-L-Rhap-(1→4)-ß-D-GalpA-(1→3)-ß-D-Galp-(1→] with the side chain →5)-ß-D-Arap (1→3, 5)-ß-D-Arap (1→ attached to the backbone through O-4 of (1→3,4)-L-Rhap. T-ß-D-Galp is attached to the backbone through O-6 of (1→3,6)-ß-D-Galp residues and T-ß-D-Ara is connected to the end group of each chain. The anti-inflammatory effects of KMPS-2E and the underlying mechanisms using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and carrageenan-induced hind paw edema were investigated. KMPS-2E (50, 100 and 200 µg/mL) inhibits iNOS, TLR4, phospho-NF-κB-p65 expression, phosphor-IKK, phosphor-IκB-α expression as well as the degradation of IκB-α and the gene expression of inflammatory cytokines (TNF-α, IL-1ß, iNOS and IL-6) mediated by the NF-κB signal pathways in macrophages. KMPS-2E also inhibited LPS-induced activation of NF-κB as assayed by electrophorectic mobility shift assay (EMSA) in a dose-dependent manner and it reduced NF-κB DNA binding affinity by 62.1% at 200 µg/mL. In rats, KMPS-2E (200 mg/kg) can significantly inhibit carrageenan-induced paw edema as ibuprofen (200 mg/kg) within 3 h after a single oral dose. The results indicate that KMPS-2E is a promising herb-derived drug against acute inflammation.


Asunto(s)
Aconitum/química , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Lipopolisacáridos/farmacología , FN-kappa B/metabolismo , Extractos Vegetales/uso terapéutico , Polisacáridos/uso terapéutico , Animales , Western Blotting , Línea Celular , Ensayo de Cambio de Movilidad Electroforética , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Extractos Vegetales/química , Polisacáridos/química , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos
17.
PLoS One ; 7(4): e35636, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22545124

RESUMEN

BACKGROUND: Small molecules have been shown to modulate the neurogenesis processes. In search for new therapeutic drugs, the herbs used in traditional medicines for neurogenesis are promising candidates. METHODOLOGY AND PRINCIPAL FINDINGS: We selected a total of 45 natural compounds from Traditional Chinese herbal medicines which are extensively used in China to treat stroke clinically, and tested their proliferation-inducing activities on neural stem/progenitor cells (NSPCs). The screening results showed that salvianolic acid B (Sal B) displayed marked effects on the induction of proliferation of NSPCs. We further demonstrated that Sal B promoted NSPCs proliferation in dose- and time-dependent manners. To explore the molecular mechanism, PI3K/Akt, MEK/ERK and Notch signaling pathways were investigated. Cell proliferation assay demonstrated that Ly294002 (PI3K/Akt inhibitor), but neither U0126 (ERK inhibitor) nor DAPT (Notch inhibitor) inhibited the Sal B-induced proliferation of cells. Western Blotting results showed that stimulation of NSPCs with Sal B enhanced the phosphorylation of Akt, and Ly294002 abolished this effect, confirming the role of Akt in Sal B mediated proliferation of NSPCs. Rats exposed to transient cerebral ischemia were treated for 4 weeks with Sal B from the 7th day after stroke. BrdU incorporation assay results showed that exposure Sal B could maintain the proliferation of NSPCs after cerebral ischemia. Morris water maze test showed that delayed post-ischemic treatment with Sal B improved cognitive impairment after stroke in rats. SIGNIFICANCE: Sal B could maintain the NSPCs self-renew and promote proliferation, which was mediated by PI3K/Akt signal pathway. And delayed post-ischemic treatment with Sal B improved cognitive impairment after stroke in rats. These findings suggested that Sal B may act as a potential drug in treatment of brain injury or neurodegenerative diseases.


Asunto(s)
Células Madre Adultas/efectos de los fármacos , Benzofuranos/farmacología , Medicamentos Herbarios Chinos/farmacología , Células-Madre Neurales/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Células Madre Adultas/citología , Células Madre Adultas/metabolismo , Animales , Bromodesoxiuridina/análisis , Bromodesoxiuridina/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Regulación de la Expresión Génica/efectos de los fármacos , Aprendizaje/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Memoria/efectos de los fármacos , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Wistar , Receptores Notch/metabolismo
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