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1.
Small ; : e2405396, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136423

RESUMEN

Covalent organic frameworks (COFs) are promising porous materials due to their high specific surface area, adjustable structure, highly ordered nanochannels, and abundant functional groups, which brings about wide applications in the field of gas adsorption, hydrogen storage, optics, and so forth. In recent years, COFs have attracted considerable attention in electrochemical energy storage and conversion. Specifically, COF-based functional separators are ideal candidates for addressing the ionic transport-related issues in high-energy batteries, such as dendritic formation and shuttle effect. Therefore, it is necessary to make a comprehensive understanding of the mechanism of COFs in functional separators. In this review, the advantages, applications as well as synthesis of COFs are firstly presented. Then, the mechanism of COFs in functional separators for high-energy batteries is summarized in detail, including pore channels regulating ionic transport, functional groups regulating ionic transport, adsorption effect, and catalytic effect. Finally, the application prospect of COFs-based separators in high-energy batteries is proposed. This review may provide new insights into the design of functional separators for advanced electrochemical energy storage and conversion systems.

2.
Bioorg Chem ; 151: 107657, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39053099

RESUMEN

Six new polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperidiones A-F (1-6), were obtained from Hypericum perforatum L. Their structures were characterized via extensive spectroscopic analyses, the circular dichroism data of the in situ formed [Mo2(OCOCH3)4] complexes, the nuclear magnetic resonance calculation with DP4 + probability analysis, and the calculated electronic circular dichroism (ECD) spectra. Compounds 1-6 are bicyclic polyprenylated acylphloroglucinols with a major bicyclo[3.3.1]nonane-2,4,9-trione skeleton. Notably, compound 1 is a rare PPAP with a hydroperoxy group, and a plausible biosynthetic pathway for 1 was proposed. Compounds 4 and 6 exhibited significant neuroprotective effects under 10 µM against corticosterone (CORT)-injured SH-SY5Y cells. Furthermore, compound 4 demonstrated a noteworthy antidepressant effect at the dose of 5 mg/kg in the tail suspension test (TST) of mice, which was equivalent to 5 mg/kg of fluoxetine. And it potentially exerted an antidepressant effect through the hypothalamic-pituitary-adrenal (HPA) axis.


Asunto(s)
Antidepresivos , Hypericum , Floroglucinol , Hypericum/química , Antidepresivos/farmacología , Antidepresivos/química , Antidepresivos/aislamiento & purificación , Animales , Floroglucinol/farmacología , Floroglucinol/química , Floroglucinol/aislamiento & purificación , Ratones , Humanos , Estructura Molecular , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Relación Estructura-Actividad , Relación Dosis-Respuesta a Droga , Masculino , Línea Celular Tumoral , Compuestos Policíclicos/farmacología , Compuestos Policíclicos/química , Compuestos Policíclicos/aislamiento & purificación , Corticosterona , Suspensión Trasera
3.
Pharmacol Res ; 187: 106625, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36563870

RESUMEN

Increasing evidence suggests that the failure of clinical antidepressants may be related with neuroinflammation. The NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome is an intracellular multiprotein complex, and has been considered as a key contributor to the development of neuroinflammation. Inhibition of NLRP3 inflammasome is an effective method for depression treatment. In this review, we summarized current researches highlighting the role of NLRP3 inflammasome in the pathology of depression. Firstly, we discussed NLRP3 inflammasome activation in patients with depression and animal models. Secondly, we outlined the possible mechanisms driving the activation of NLRP3 inflammasome. Thirdly, we discussed the pathogenetic role of NLRP3 inflammasome in depression. Finally, we overviewed the current and potential antidepressants targeting the NLRP3 inflammasome. Overall, the inhibition of NLRP3 inflammasome activation may be a potential therapeutic strategy for inflammation-related depression.


Asunto(s)
Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Animales , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Depresión/tratamiento farmacológico , Enfermedades Neuroinflamatorias , Antidepresivos/uso terapéutico , Antidepresivos/farmacología
4.
Nanotechnology ; 34(17)2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36645911

RESUMEN

Sensitive detection of nucleolin (NCL) is of great significance for the early diagnosis of cancer. In this work, as a new type of two-dimensional (2D) transition metal dichalcogenides (TMDCs), TaS2nanoflakes (NFs) were precisely constructed by atomic layer deposition (ALD) on carbon fiber paper (CFP) with high specific surface area.In situobservation showed that the nucleation and growth of TaS2nanoflakes were precisely controlled by the number of ALD cycles, thereby regulating their electrochemical properties. The electrochemical performance of TaS2NFs was observed in depth, and compared with that of traditional 2D TMDCs. Due to the high surface area and conductivity, anodic/cathodic current of ∼1570µA of TaS2NFs/CFP can be obtained. Subsequently, an electrochemical biosensor based on ALD-constructed TaS2NFs/CFP for cancer-related NCL detection was fabricated. Due to the excellent electrochemical performance of TaS2NFs/CFP, ultrasensitive detection of NCL in the linear range of 0.1 pM-10 nM with a detection limit of 0.034 pM was achieved.


Asunto(s)
Neoplasias , Fosfoproteínas , Proteínas de Unión al ARN , Fibra de Carbono , Conductividad Eléctrica , Neoplasias/diagnóstico , Nucleolina
5.
Chem Biodivers ; 20(3): e202300013, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36752551

RESUMEN

Phytochemical investigation of the roots of Euphorbia ebracteolata Hayata resulted in the isolation of three new rosane diterpenoids, euphebracteolatins C-E (1-3), along with fourteen known analogs (4-17). Their structures were determined on the basis of extensive spectroscopic analysis including HR-ESI-MS, 1D and 2D NMR. Euphebracteolatin C (1) contains a C-1/C-10 double bond and a keto group at C-7, and euphebracteolatins D and E (2-3) possess an aromatic ring-A in their skeleton. The plausible biogenetic pathways of all the isolates were also proposed. Furthermore, compounds 1 and 9 showed selective cytotoxicity against HepG2 cells with IC50 values of 14.29 and 12.33 µM, respectively, and 2-3 displayed moderate cytotoxicity against three human cancer lines, with IC50 values ranging from 23.69 to 39.25 µM.


Asunto(s)
Diterpenos , Euphorbia , Humanos , Estructura Molecular , Euphorbia/química , Espectroscopía de Resonancia Magnética , Diterpenos/química , Raíces de Plantas/química
6.
Phytother Res ; 36(6): 2272-2299, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35583806

RESUMEN

Iridoid glycosides (IGs) are found in many medicinal and edible plants, such as Gardenia jasminoides, Cistanche tubulosa, Eucommia ulmoides, Rehmanniae Radix, Lonicera japonica, and Cornus officinalis. Loganin, an IG, is one of the main active ingredient of Cornus officinalis Sieb. et Zucc., which approved as a medicinal and edible plant in China. Loganin has been widely concerned due to its extensive pharmacological effects, including anti-diabetic, antiinflammatory, neuroprotective, and anti-tumor activities, etc. Studies have shown that these underlying mechanisms include anti-oxidation, antiinflammation and anti-apoptosis by regulating a variety of signaling pathways, such as STAT3/NF-κB, JAK/STAT3, TLR4/NF-κB, PI3K/Akt, MCP-1/CCR2, and RAGE/Nox4/p65 NF-κB signaling pathways. In order to better understand the research status of loganin and promote its application in human health, this paper systematically summarized the phytochemistry, analysis methods, synthesis, pharmacological properties and related mechanisms, and pharmacokinetics based on the research in the past decades.


Asunto(s)
Cornus , Iridoides , Transducción de Señal , Cornus/química , Humanos , Iridoides/farmacocinética , Iridoides/farmacología , FN-kappa B/metabolismo , Fosfatidilinositol 3-Quinasas/farmacología
7.
J Org Chem ; 86(8): 5894-5900, 2021 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-33793234

RESUMEN

Fischdiabietane A (1), a novel asymmetric diterpenoid dimer with a unique nonacyclic 6/6/6/5/7/6/6/6/6 ring system possessing unprecedented 2-oxaspiro[4.5]decane-1-one and 2-oxabicyclo[3.2.2]nonane frameworks in D/E/F rings, was isolated from the roots of Euphorbia fischeriana. Its structure was determined by spectroscopic techniques, electronic circular dichroism calculations, and X-ray diffraction experiments. Notably, 1 is the first abietane-type [4 + 2] Diels-Alder dimer identified from nature. The IC50 of 1 against T47D cells was about sixfold higher than that of cisplatin (the positive control). Furthermore, 1 induced apoptosis in T47D cells through the activation of caspase-3 and the degradation of poly(ADP-ribose) polymerase.


Asunto(s)
Diterpenos , Euphorbia , Carbono , Estructura Molecular , Raíces de Plantas , Esqueleto
8.
Bioorg Chem ; 117: 105399, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34688131

RESUMEN

Cornusdiridoid A-F (1-6), six unusual cornuside-morroniside secoiridoid dimers, and their possible new biogenetic precursor, 3″,5″-dehydroxycornuside (7), together with four known secoiridoids (8-11), were obtained from the fruits of Cornus officinalis. Their structures were elucidated on the basis of various spectroscopic and chemical methods. A plausible biosynthetic pathway of compounds 1-11 was proposed. The α-glucosidase inhibitory, antioxidant and anti-inflammatory activities of these isolates were evaluated. Some of them emerged out as potent antidiabetic, anti-inflammatory and free radical scavenging agents. Molecular docking was also carried out for antidiabetic target α-glucosidase to investigate the possible binding modes of the most potent α-glucosidase inhibitor, vincosamide (9). These results revealed that the secoiridoids from C. officinalis fruits may be served as new potential antidiabetic agents to prevent and treat type 2 diabetes.


Asunto(s)
Antioxidantes/farmacología , Cornus/química , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de Glicósido Hidrolasas/farmacología , Iridoides/farmacología , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Antioxidantes/química , Diabetes Mellitus Tipo 2/metabolismo , Descubrimiento de Drogas , Frutas/química , Inhibidores de Glicósido Hidrolasas/química , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Iridoides/química , Ratones , Simulación del Acoplamiento Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Células RAW 264.7 , alfa-Glucosidasas/metabolismo
9.
J Asian Nat Prod Res ; 21(8): 782-797, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30608002

RESUMEN

Inappropriate use of acetaminophen (APAP) can lead to morbidity and mortality secondary to hepatic necrosis. Ginsenoside Rg1 is a major active ingredient in processed Panax ginseng, which is proved to elicit biological effects. We hypothesized the beneficial effect of Rg1 on APAP-mediated hepatotoxicity was through Nrf2/ARE pathway. The study was conducted in cells and mice, comparing the actions of Rg1. Rg1 significantly improved cell survival rates and promoted the expression of antioxidant proteins. Meanwhile, Rg1 reduced the excessive ROS and the occurrence of cell apoptosis, which were related to Nrf2/ARE pathway. Expression of Nrf2 has a certain cell specificity.


Asunto(s)
Acetaminofén/toxicidad , Elementos de Respuesta Antioxidante/fisiología , Apoptosis/efectos de los fármacos , Ginsenósidos/farmacología , Factor 2 Relacionado con NF-E2/fisiología , Estrés Oxidativo/efectos de los fármacos , Animales , Antioxidantes/farmacología , Células HEK293 , Células Hep G2 , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos
10.
Int J Syst Evol Microbiol ; 67(2): 454-459, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27902308

RESUMEN

An alkaliphilic strain designed MN-1T was isolated from a desert sand sample collected from Tengger desert, north-western China. To delineate its taxonomic position, this Gram-stain-negative, rod-shaped, strictly aerobic bacterium was subjected to a polyphasic taxonomic study. Growth was observed at temperatures from 4 to 37 °C (optimum 30-32 °C), at salinities from 0 to 2 % (optimum 1 %) and at pH from 6.5 to 12.0 (optimum 7.0-9.0). Phylogenetic analysis based on 16S rRNA gene sequencing showed that strain MN-1T was a member of the genus Altererythrobacterbut could be distinguished from recognized species of this genus. Compared to the reference strains, the novel strain was flagellated and motile by means of polar flagella. The predominant respiratory quinone was ubiquinone-10 and the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, sphingoglycolipid, phosphatidylglycerol, phosphatidylcholine, one unidentified glycolipid, one unidentified phospholipid and four unidentified lipids. The predominant fatty acids were C18 : 1ω7c, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. These chemotaxonomic traits were in agreement with the characteristics of the genus Altererythrobacter. Strain MN-1T was most closely related to Altererythrobacter xinjiangensis S3-63T (96.9 % 16S rRNA gene sequence similarity), followed by Altererythrobacter dongtanensis JM27T (96.4 %) and Altererythrobacter marinus H32T (96.1 %). The G+C content of the genomic DNA of strain MN-1T was 67.0 mol%. On the basis of data from this polyphasic taxonomic study, strain MN-1T is proposed as the type strain of a novel species of the genus Altererythrobacter, named as Altererythrobacter soli sp. nov. (=KCTC 52135T=MCCC 1K02066T).


Asunto(s)
Alphaproteobacteria/clasificación , Clima Desértico , Filogenia , Microbiología del Suelo , Alphaproteobacteria/genética , Alphaproteobacteria/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Glucolípidos/química , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Dióxido de Silicio , Ubiquinona/química
11.
Nanotechnology ; 28(42): 425401, 2017 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-28749370

RESUMEN

The hierarchical nanosheet-based Ni3S2 microspheres directly grew on Ni foam using a two-step hydrothermal method. The microsphere with a diameter of ∼1 microns and a rough surface was well connected to each other without any binders to provide a larger specific surface area, shorter ion/electron diffusion paths, richer electroactive sites as a supercapacitor electrode. As a three-electrode supercapacitor, it delivers a high specific capacity of 981.8 F g-1 at 2 A g-1, an excellent rate capability of 436.4 F g-1 at 12 A g-1, and a good cycling stability of 950.9 F g-1 with 96.9% retention after 1000 cycles at 2 A g-1. Furthermore, an asymmetric supercapacitor based on Ni3S2-microsphere as a positive electrode and active carbon as a negative electrode shows a high energy density of 29.4 Wh kg-1 at 324.5 W kg-1 and a high power density of 3197.6 W kg-1 at 15.1 Wh kg-1. This work demonstrates that nanosheet-based Ni3S2 microspheres coated Ni foam can be an effective electrode for a real supercapacitor.

12.
Acta Pharmacol Sin ; 37(12): 1525-1533, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27616576

RESUMEN

AIM: Accumulation of α-synuclein (α-syn) in the brain is a characteristic of Parkinson's disease (PD). In this study, we investigated whether treatment with tunicamycin, an endoplasmic reticulum (ER) stress inducer, led to the accumulation of α-syn in PC12 cells, and where α-syn protein was accumulated, and finally, whether bibenzyl compound 20c, a novel compound isolated from Gastrodia elata (Tian ma), could alleviate the accumulation of α-syn and ER stress activation in tunicamycin-treated PC12 cells. METHODS: PC12 cells were treated with tunicamycin for different time (6 h, 12 h, 24 h, 48 h). Cell viability was determined by a MTT assay. Subcellular fractions of ER and mitochondria were extracted with the Tissue Endoplasmic reticulum Isolation Kit. The levels of α-syn protein and ER-stress-associated downstream chaperones were detected using Western blots and immunofluorescence. RESULTS: Treatment of PC12 cells with tunicamycin (0.5-10 µg/mL) dose-dependently increased the accumulation of α-syn monomer (19 kDa) and oligomer (55 kDa), and decreased the cell viability. Accumulation of the two forms of α-syn was observed in both the ER and mitochondria with increasing treatment time. Co-treatment with 20c (10-5 mol/L) significantly increased the viability of tunicamycin-treated cells, reduced the level of α-syn protein and suppressed ER stress activation in the cells, evidenced by the reductions in phosphorylation of eIF2α and expression of spliced ATF6 and XBP1. CONCLUSION: Tunicamycin treatment caused accumulation of α-syn monomer and oligomer in PC12 cells. Bibenzyl compound 20c reduces the accumulation of α-syn and inhibits the activation of ER stress, which protected PC12 cells against the toxicity induced by tunicamycin.


Asunto(s)
Compuestos de Bencidrilo/farmacología , Bibencilos/farmacología , Estrés del Retículo Endoplásmico/efectos de los fármacos , Gastrodia/química , Fenoles/farmacología , Sustancias Protectoras/farmacología , Tunicamicina/toxicidad , Animales , Células PC12 , Ratas , alfa-Sinucleína/metabolismo
13.
J Asian Nat Prod Res ; 18(8): 765-78, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27229011

RESUMEN

Rg1 has shown multiple pharmacological activities and been considered to be evaluated for hepatic protective activity, as Rg1 could modulate different pathways in various diseases. Herein we assessed its effect and potential mechanism in a newly modified ethanol model. C57BL/6 mice were fed with Lieber-DeCarli liquid diet containing ethanol or isocaloric maltose dextrin as control diet with or without Rg1. Meanwhile, bicyclol was treated as positive drug to compare the efficacy of Rg1 against alcoholic hepatotoxicity. According to our data, Rg1 indeed improved the survival rate and lowered the abnormal high levels of serum parameters. H&E and Oil Red O staining indicated that the condition of liver damage was mitigated by Rg1 administration. Furthermore, AMPK and Nrf2 pathways were all modulated at both RNA and protein levels. In accordance with these findings, Rg1 effectively protected against alcoholic liver injury, possibly by modulating metabolism, suppressing oxidative stress, and enhancing oxidant defense systems of Nrf2 pathway. In vitro, Rg1 has no cell toxicity and promotes Nrf2 translocate into nuclear. In summary, we demonstrate that Rg1 is a potent activator of Nrf2 pathway, and could therefore be applied for prevention of hepatic damage.


Asunto(s)
Ginsenósidos/farmacología , Hígado/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Femenino , Ginsenósidos/química , Humanos , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Factor 2 Relacionado con NF-E2/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(8): 2613-6, 2016 Aug.
Artículo en Zh | MEDLINE | ID: mdl-30074374

RESUMEN

On-line element content detection in iron and steel industry is one of the key techniques to ensure the quality in iron and steel metallurgy. Laser Induced Breakdown Spectroscopy (LIBS) has been applied to on-line components detection in molten steel. We have built LIBS system for components detection of molten steel in laboratory. The system consists of a Q-switched Nd∶YAG laser (repetition rate 10 Hz, wavelength 1 064 nm, pulse length 10 ns, pulse energy about 120 mJ), high frequency induction furnace (temperature 1 600 ℃), spectrometer (wavelength range 186~310 nm, spectral resolution 0.1 nm), laser focusing and spectral signal collecting system. Multi-elements were detected in molten steel with the application of deep-UV detector coating and solarization resistant fibers. According to the calibration curves of C, S, Mn and Cr, the limit of detections are 169, 15, 58.9 and 210 µg·g-1 respectively. The R-squares of calibration curves of C, S, Mn, and Cr are better than 0.96 by using appropriate analytical lines and reference lines. At the same time, through the comparison of different elements, we find the best calibration curve of different element need different delay conditions.

15.
Acta Pharmacol Sin ; 36(3): 311-22, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25640478

RESUMEN

AIM: Protopanaxtriol (Ppt) is extracted from Panax ginseng Mayer. In the present study, we investigated whether Ppt could protect against 3-nitropropionic acid (3-NP)-induced oxidative stress in a rat model of Huntington's disease (HD) and explored the mechanisms of action. METHODS: Male SD rats were treated with 3-NP (20 mg/kg on d 1, and 15 mg/kg on d 2-5, ip). The rats received Ppt (5, 10, and 20 mg/kg, po) daily prior to 3-NP administration. Nimodipine (12 mg/kg, po) or N-acetyl cysteine (NAC, 100 mg/kg, po) was used as positive control drugs. The body weight and behavior were monitored within 5 d. Then the animals were sacrificed, neuronal damage in striatum was estimated using Nissl staining. Hsp70 expression was detected with immunohistochemistry. Reactive oxygen species (ROS) generation was measured using dihydroethidium (DHE) staining. The levels of components in the Nrf2 pathway were measured with immunohistochemistry and Western blotting. RESULTS: 3-NP resulted in a marked reduction in the body weight and locomotion activity accompanied by progressive striatal dysfunction. In striatum, 3-NP caused ROS generation mainly in neurons rather than in astrocytes and induced Hsp70 expression. Administration of Ppt significantly alleviated 3-NP-induced changes of body weight and behavior, decreased ROS production and restored antioxidant enzymes activities in striatum. Moreover, Ppt directly scavenged free radicals, increased Nrf2 entering nucleus, and the expression of its downstream products heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidase 1 (NQO1) in striatum. Similar effects were obtained with the positive control drugs nimodipine or NAC. CONCLUSION: Ppt exerts a protective action against 3-NP-induced oxidative stress in the rat model of HD, which is associated with its anti-oxidant activity.


Asunto(s)
Antioxidantes/farmacología , Ganglios Basales/efectos de los fármacos , Enfermedad de Huntington/prevención & control , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Nitrocompuestos , Propionatos , Sapogeninas/farmacología , Animales , Ganglios Basales/metabolismo , Ganglios Basales/patología , Ganglios Basales/fisiopatología , Conducta Animal/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Proteínas HSP70 de Choque Térmico/metabolismo , Hemo Oxigenasa (Desciclizante)/metabolismo , Humanos , Enfermedad de Huntington/inducido químicamente , Enfermedad de Huntington/metabolismo , Enfermedad de Huntington/patología , Enfermedad de Huntington/fisiopatología , Masculino , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Actividad Motora/efectos de los fármacos , NAD(P)H Deshidrogenasa (Quinona)/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Neuronas/metabolismo , Neuronas/patología , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , Pérdida de Peso/efectos de los fármacos
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(2): 304-8, 2015 Feb.
Artículo en Zh | MEDLINE | ID: mdl-25970882

RESUMEN

The present paper presents an auto-focus laser-induced breakdown spectroscopy (LIBS) remote measuring system. This system contains a Schwarzschild telescope, which consists of a convex mirror and a concave mirror. The two spherical mirrors are coaxially placed. The convex mirror is mounted on a motorized linear translation stage. With this motorized linear translation stage, the convex mirror can move along the optical axis to change the spacing between the convex mirror and the concave mirror. Therefore the focal length can be adjusted to focus the laser on samples at different distances and collect the plasma spectra. The advantages of the telescope system include, firstly, the light path of laser focusing and spectra signal collection is the same, which make it easier for mounting and collimation; secondly, the light path of the telescope uses total reflection type, which is fit for the detection in ultra-violate region; finally, the telescope consists of only two spherical mirrors which are relatively easier to manufacture. Within the translation range of the motorized linear translation stage, the focal length of the telescope in this paper can be adjusted from 1.5 to 3.6 m. The diameter of the focusing spot varies from 0.5 to 1.0 mm. Utilizing this telescope system, LIBS experiments were conducted using copper sample. And the characteristic lines of Cu element (Cu I 223.01 nm, Cu I 224.43 nm) obtained are used for the auto focusing. By investigating the relation of the area of spectral lines covered and the spacing between the mirrors, the optimal laser focusing location was obtained. The LIBS experiment results show that the system functions well, fulfilling the demand of remote ablation of sample and LIBS spectral measuring, and the telescope is able to auto-focus the laser on samples at different position to perform remote LIBS experiment.

17.
Acta Pharmacol Sin ; 35(8): 1031-44, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24976156

RESUMEN

AIM: To investigate the anti-fibrosis effects of ginsenoside Rg1 on alcohol- and CCl4-induced hepatic fibrosis in rats and to explore the mechanisms of the effects. METHODS: Rats were given 6% alcohol in water and injected with CCl4 (2 mL/kg, sc) twice a week for 8 weeks. Rg1 (10, 20 and 40 mg/kg per day, po) was administered in the last 2 weeks. Hepatic fibrosis was determined by measuring serum biochemical parameters, HE staining, Masson's trichromic staining, and hydroxyproline and α-SMA immunohistochemical staining of liver tissues. The activities of antioxidant enzymes, lipid peroxidation, and Nrf2 signaling pathway-related proteins (Nrf2, Ho-1 and Nqo1) in liver tissues were analyzed. Cultured hepatic stellate cells (HSCs) of rats were prepared for in vitro studies. RESULTS: In the alcohol- and CCl4-treated rats, Rg1 administration dose-dependently suppressed the marked increases of serum ALT, AST, LDH and ALP levels, inhibited liver inflammation and HSC activation and reduced liver fibrosis scores. Rg1 significantly increased the activities of antioxidant enzymes (SOD, GSH-Px and CAT) and reduced MDA levels in liver tissues. Furthermore, Rg1 significantly increased the expression and nuclear translocation of Nrf2 that regulated the expression of many antioxidant enzymes. Treatment of the cultured HSCs with Rg1 (1 µmol/L) induced Nrf2 translocation, and suppressed CCl4-induced cell proliferation, reversed CCl4- induced changes in MDA, GPX, PCIII and HA contents in the supernatant fluid and α-SMA expression in the cells. Knockdown of Nrf2 gene diminished these actions of Rg1 in CCl4-treated HSCs in vitro. CONCLUSION: Rg1 exerts protective effects in a rat model of alcohol- and CCl4-induced hepatic fibrosis via promoting the nuclear translocation of Nrf2 and expression of antioxidant enzymes.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Tetracloruro de Carbono , Ginsenósidos/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , Cirrosis Hepática/etiología , Hígado/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Animales , Células Cultivadas , Ginsenósidos/aislamiento & purificación , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Peroxidación de Lípido/efectos de los fármacos , Hígado/patología , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/patología , Masculino , Panax/química , Ratas Wistar , Transducción de Señal/efectos de los fármacos
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 865-8, 2014 Apr.
Artículo en Zh | MEDLINE | ID: mdl-25007588

RESUMEN

Laser-Induced Breakdown Spectroscopy (LIBS) is strongly time related. Time-resolved LIBS measurement is an important technique for the research on laser induced plasma evolution and self-absorption of the emission lines. Concerning the temporal characteristics of LIBS spectrum, a method is proposed in the present paper which can achieve micros-scale time-resolved LIBS measurement by using general ms-scale detector. By setting different integration delay time of the ms-scale spectrum detector, a series of spectrum are recorded. And the integration delay time interval should be longer than the worst temporal precision. After baseline correction and spectrum fitting, the intensity of the character line was obtained. Calculating this intensity with differential method at a certain time interval and then the difference value is the time-resolved line intensity. Setting the plasma duration time as X-axis and the time-resolved line intensity as Y-axis, the evolution curve of the character line intensity can be plotted. Character line with overlap-free and smooth background should be a priority to be chosen for analysis. Using spectrometer with ms-scale integration time and a control system with temporal accuracy is 0.021 micros, experiments carried out. The results validate that this method can be used to characterize the evolution of LIBS characteristic lines and can reduce the cost of the time-resolved LIBS measurement system. This method makes high time-resolved LIBS spectrum measurement possible with cheaper system.

19.
Tumour Biol ; 34(1): 515-20, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23132295

RESUMEN

This study aims to investigate the expression and significance of GOLPH3 in human gastric cancer progression and prognosis. Using immunohistochemistry (IHC) and real-time reverse transcriptase polymerase chain reaction assay, we identified abnormally elevated expression of GOLPH3 in gastric cancer tissues compared to paired normal stomach mucosa tissues in 40 patients. In addition, the enzyme-linked immunosorbent assay (ELISA) was used to quantify serum GOLPH3 concentrations in the same 40 gastric cancer patients and 40 healthy individuals. ELISA revealed significantly higher serum concentrations of GOLPH3 in gastric cancer patients compared to healthy individuals (p = 0.002). In order to investigate the correlations between GOLPH3 and the clinicopathological features of gastric cancer, the expression of GOLPH3 in 123 gastric cancer patients were detected by IHC, and the results showed that overexpression of GOLPH3 was associated with the size of the tumor (p = 0.013), histological grade (p = 0.002), depth of invasion (p < 0.001), lymph node metastasis (p < 0.001), distant metastasis (p = 0.018), and TNM stage (p < 0.001). Kaplan-Meier survival analysis showed that high GOLPH3 expression exhibited a significant correlation with poor prognosis for gastric cancer patients. Further, Cox multivariate analysis indicated that GOLPH3 expression level was an independent prognostic factor for patients after radical resection. In conclusion, the overexpression of GOLPH3 is closely related to the progression of gastric cancer and might be regarded as an independent predictor of poor prognosis for gastric cancer.


Asunto(s)
Metástasis Linfática , Proteínas de la Membrana/metabolismo , Neoplasias Gástricas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Progresión de la Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Proteínas de la Membrana/sangre , Proteínas de la Membrana/genética , Persona de Mediana Edad , Pronóstico , ARN Mensajero/genética , ARN Mensajero/metabolismo , Neoplasias Gástricas/sangre , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(12): 3388-91, 2013 Dec.
Artículo en Zh | MEDLINE | ID: mdl-24611408

RESUMEN

Laser-induced breakdown spectroscopy (LIBS) is one of the most promising technologies to be applied to metallurgical composition online monitoring in these days. In order to study the spectral characters of LIBS spectrum and to investigate the quantitative analysis method of material composition under vacuum and high temperature environment, a LIBS measurement system was designed and set up which can be used for conducting experiments with high-temperature or molten samples in different vacuum environment. The system consists of a Q-switched Nd : YAG laser used as the light source, lens with different focus lengths used for laser focusing and spectrum signal collecting, a spectrometer used for detecting the signal of LIBS spectrums, and a vacuum system for holding and heating the samples while supplying a vacuum environment. The vacuum was achieved and maintained by a vacuum pump and an electric induction furnace was used for heating the system. The induction coil was integrated to the vacuum system by attaching to a ceramic sealing flange. The system was installed and testified, and the results indicate that the vacuum of the system can reach 1X 10(-4) Pa without heating, while the heating temperature could be about 1 600 degreeC, the system can be used for melting metal samples such as steel and aluminum and get the LIBS spectrum of the samples at the same time. Utilizing this system, LIBS experiments were conducted using standard steel samples under different vacuum or high-temperature conditions. Results of comparison between LIBS spectrums of solid steel samples under different vacuum were achieved, and so are the spectrums of molten and solid steel samples under vacuum environment. Through data processing and theoretical analyzing of these spectrums, the initial results of those experiments are in good agreement with the results that are presently reported, which indicates that the whole system functions well and is available for molten metal LIBS experiment under vacuum environment.

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