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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(10): 3404-9, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30247000

RESUMEN

Bredigite was synthesized by using the Piston-Cylinder in 1.2 GPa and 1 473 K. With external heating device and diamond anvil cell, high temperature and high pressure Raman spectra of bredigite were collected at temperatures 298, 353, 463, 543, 663, 773 and 873 K and with pressure from 1 atm up to 14.36 GPa (room temperature). The SEM image showed that the sample consisted of one crystalline phase with grain size ranging from 10~20 µm. The EPMA data suggest a chemical formula of Ca7.03(2)Mg0.98(2)Si3.94(2)O16 which was identical to the theoretical component of bredigite. The Raman spectroscopic results indicate there were 29 vibration bands of bredigite at high temperature. Some bands were merging, weakening and disappearing increasingly with the temperature, which was obvious in the range of 800~1 200 cm-1. The vibration bands of 909, 927 and 950 cm-1 disappeared at 873, 773 and 873 K, respectively. The results primarily indicated that the structure of bredigite was stable under experimental condition. In addition, isobaric mode-Grüneisen parameters and isothermal mode-Grüneisen parameters were calculated, yielding 1.47(2) and 0.45(3) as their mean values, respectively. Anharmonic coefficients were estimated based on the high temperature and high pressure Raman experiments, showing that the contributions to anharmonic-effect induced with the Si­O vibration modes were smaller than other modes.

2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(11): 3187-91, 2015 Nov.
Artículo en Zh | MEDLINE | ID: mdl-26978933

RESUMEN

Pangxidong composite granitoid pluton located in the southwestern margin of Yunkai massif. The metamorphic grade of this pluton increases from outside to inside, that is, banded-augen granitic gneisses, gneissoid granites and granites distribute in order from edge to core. X-Ray Fluorescence Spectroscopy and Plasma Mass Spectrometry are conducted to study the geochemical characteristics of the three types of rocks. The result shows that all the three types of rocks are peraluminous rocks and their contents of main elements and rare earth elements change gradually. From granitic gneisses to granites, the contents of Al2O3, CaO, MgO, TiO2, total rare earth elements and light rare earth elements increase, but the contents of SiO2 and heavy rare earth elements decrease. It is suggested that the phylogenetic relationship exists between granitic gneisses, gneissoid granites and granites during the multi-stage tectonic evolution process. Furthermore, the remelting of metamorphosed supracrustal rocks in Yunkai massif is probably an important cause of granitoid rocks forming. The evolutionary mechanism is probably that SiO2 and heavy rare earth elements were melt out from the protolith and gradually enriched upward, but Al2O3, CaO, MgO, TiO2 and light rare earth elements enriched downward.

3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(9): 2558-62, 2015 Sep.
Artículo en Zh | MEDLINE | ID: mdl-26669167

RESUMEN

The Feieling Pb-Zn deposit of skarn-type is located the in Southwest margin of Yunkai massif, China. This ore deposit can be divided into wall rock near ore, concealed rock mass, endoskarn, exoskarn and orebody. The Raman and FTIR spectrum are conducted to study the mineralogical characteristics of quartz and calcite from five types of rocks from Feieling skarn-type deposit. The analysis shows that the quartz included in the near ore wall rock, endoskarn and exoskarn, comparing with recrystallized quartz of concealed rock mass, has a tend to change into low symmetry quartz in varying degrees. The crystalinity and order degree of quartz from near ore wall rock to concealed rock mass and to endoskarn are becoming higher, but that of quartz from different exoskarn samples display no regular. The origin or the quartz microstructure changes may be related to the multi-stage evolution of skarn mineralization process. The quartz, included in near ore wall rock, endoskarn and exoskarn, become easier to recrystallize and adjust microstructure under the influence of the multi-stage hydrothermal and temperature effect. In anyone sample, the earlier crystalline calcite, showing subhedral-euhedral crystal, display higher crystalinity and order degree. On the contrary, the later crystalline calcite, showing xenomorphic crystal, display lower crystalinity and order degree. Calcite crystal of exoskarn rock contains some silica impurity, while endoskarn and orebody rock is pure. The purity of calcite crystal may relate to Multi-stage evolution of skarn mineralization process. At the early and late skarn stage, active silica-containing fluid is easier to join into calcite, which is under higher temperature environments. On the contrary, at the late quartz-surfide stage, the later crystalized calcite displays higher purity, which is under lower temperature environments. Therefore, spectral characteristics of quartz and calcite reflect multi-stage evolution of skarn mineralization process.

4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(11): 3005-10, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25752047

RESUMEN

Siliceous rocks were extensively distributed in the marine volcanic sedimentary formation of Erlangping Group in the Early Paleozoic in eastern Qinling area. These siliceous rocks formed in the same age, but had differences in the degree of crystallization and order because of the late diagenetic evolution. In the present study, the major elements and order degree of the siliceous rocks were studied, which were from the Erlangping Group in Xixia area, Songxian area and Nanzhao area of eartern Qinling orogenic belt. As shown in the results, the siliceous rocks contained SiO2 with percentage between 84.75% and 94.12% and average of 89.09%. The SiO2/(K2O+Na2O) values were from 26.69 to 114.78 with 65.67 as its average, and the values of SiO2/Al2O3 were from 10.48 to 61.52 with average of 30.58. These above characteristics excellently agreed with the geochemical characteristics of hydrothermal siliceous rocks, which deposited in the continental margin environment. In the Raman analytical results, the quartz contributed to the characteristic Raman shifts at 394, 464, 465 and 467 cm(-1). In the results of Gaussian fitting the degrees of order increased with the order of siliceous rocks of Songxian area, Nanzhao area and Xixia area, which were witnessed by the descending in FWHM values of quartz in the siliceous rocks of Songxian area, Nanzhao area and Xixia area orderly. Disagreeing with the FWHM values of Gaussian fitting, the silica contents of the siliceous rocks had a rising trend of Songxian (87.36%), Nanzhao (89.57%), Xixia area (90.35%), which meant a descending in impurity elements with the order of Songxian area, Nanzhao area and Xixia areas. According to this, there was high agreement between lower crystallinity degree and higher purity of silica, and this denoted that the rising in order degree of silica would result in lower impurity in siliceous rocks. Although the crystallinity degrees could change with the influences of temperature, pressure and its natural property, the impurity elements decreased with the rising in crystallinity degrees of silica. Although there was excluding of impurity elements during the increase in degrees of crystallinity and order, the key factor for the diversities of major elements in siliceous rocks was not likely to be the excluding of impurity elements during the increase in the crystallinity degrees in silica In this study, the Raman analysis exhibited to be an effective way to understand the degree of order for the silica of the siliceous rocks, which would be a potential way to study the subsequent diagenetic evolution of siliceous rocks.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(12): 3333-9, 2014 Dec.
Artículo en Zh | MEDLINE | ID: mdl-25881434

RESUMEN

The Xionger Group was originated from the volcanic eruption and sedimentation in Precambrian, whose sedimentary strata at the top were named Majiahe Formation. In the Majiahe Formation, there were hydrothermal chert widely distributed, which were exhibited to be interlayers in the volcanic rocks. The polarized microscope, X-ray diffraction (XRD), Raman and electron back scatter diffraction (EBSD) were conducted to study the characteristics in micro area of the jasperite samples, which were from the sedimentary interlayers in the volcanic rocks of Majiahe Formation in Xionger Group. As shown in the microphotographs and EBSD images, the quartz in the chert had small grain size, low degree of crystallinity and close packed structure, which quite agreed with the characteristics of hydrothermal sedimentary chert. In the chert of Xionger Group, there were clear banded (or lamellar) structures which were contributed by the diversities of the grain size and mineral composition. The different bands (or lamellars) had alternative appearance repeatedly, and denoted the diversities and periodic changes in the substance supply during the precipitation. According to the results of the XRD analysis, the majority minerals of the chert was low temperature quartz, whose lattice parameters were a=b=0.4913 nm, c=0.5405 nm and Z=3. As denoted in the EBSD image and result of Raman analysis, several impurity minerals were formed in the chert in different stages, whose geneses and formation time were quite different. The clay minerals and pyrite were scattered in distribution, and should be contributed by the original sedimentation. On contrary, the felsic minerals and mafic silicate minerals were originated from the sedimentation of tuffaceous substance during the volcanic eruption. The minerals of volcanic genesis had relatively larger grain size, and they deposited together with the hydrothermal sediments to form the bands (or lamellars) of coarse minerals. However, the hydrothermal sedimentation contributed to the bands (or lamellars) with minerals of much smaller grain size, which therefore resulted in diversities from the other bands (or lamellars). According to this, the repeated bands (or lamellars) denoted the volcanic activities were cyclic during the formation of the chert. What's more, the carbonate vein came from the precipitation of subsequent hydrothermal fluids in the fracture of the chert, which contributed to the changes (e. g. rising in crystallinity degree of silica and formation of micro-structure of new silicate) near the interface between chert and the carbonate vein. Although there were many impurity minerals with complex genesis, the relatively lower content of silica in the chert of Xionger Group was due to the volcanic mineral mainly. Since there were impurity minerals of volcanic genesis in relatively large amount, the content of silica in the chert of Xionger Group was hence relatively low. In this study, the Raman analysis was witnessed to be an effective way in the researches on the chert, and could open out the type of mineral, micro-structure and degrees of crystallinity (or order). These characteristics were well kept in the micro-area, and played significant roles to reflect and understand the formation mechanism and subsequent evolution of the chert.

6.
Mediators Inflamm ; 2013: 354087, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23431240

RESUMEN

The present study was carried out to investigate the effects and mechanisms of polydatin (PD) in septic mice. The model of cecal ligation and puncture (CLP-)induced sepsis was employed. Pretreatment of mice with PD (15, 45, and 100 mg/kg) dose-dependently reduced sepsis-induced mortality and lung injury, as indicated by alleviated lung pathological changes and infiltration of proteins and leukocytes. In addition, PD inhibited CLP-induced serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) production, lung cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase isoform (iNOS) protein expressions and NF-κB activation. Notably, PD upregulated the expression and activity of heme oxygenase (HO-)1 in lung tissue of septic mice. Further, the protective effects of PD on sepsis were abrogated by ZnPP IX, a specific HO-1 inhibitor. These findings indicated that PD might be an effective antisepsis drug.


Asunto(s)
Glucósidos/uso terapéutico , Hemo-Oxigenasa 1/metabolismo , Lesión Pulmonar/tratamiento farmacológico , Lesión Pulmonar/enzimología , Sepsis/enzimología , Sepsis/metabolismo , Estilbenos/uso terapéutico , Animales , Líquido del Lavado Bronquioalveolar , Interleucina-6/sangre , Lesión Pulmonar/sangre , Ratones , Óxido Nítrico/metabolismo , Distribución Aleatoria , Sepsis/sangre , Factor de Transcripción ReIA/metabolismo , Factor de Necrosis Tumoral alfa/sangre
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(5): 1374-8, 2013 May.
Artículo en Zh | MEDLINE | ID: mdl-23905355

RESUMEN

The XRD, FTIR and Raman spectrum were employed to study the characters of quartz from three types of rock samples, which are mineralized rock sample, near ore body rock sample and far away from ore body rock sample in Heliao lead-zinc polymetallic ore district. The research shows that the quartz in the mineralized rock and far away from ore body rock is pure, while the quartz in near ore body rock contains a small amount of impurities. But such small amounts of impurities did not cause apparent change in the quartz lattice parameters. From far away from ore body rock-->near ore body rock-->mineralized rock, the crystallinity and order degree of quartz are higher and higher. And the quartz in the mineralized rock has a trend to change into low symmetry quartz. It's a unique to mineralized rock that the quartz's absorption peak at 1 050 cm(-1) was split into two strongest ones. It can be used as the signs of whether exists mineralization. The cause for the quartz microstructure changes may be related to the activities of late mineralized hydrothermal fluids. Late hydrothermal influence was very weak to the quartz far away from ore body rock. And through the impact of the multi-stage hydrothermal effect, the quartz in mineralized rock may be purified by recrystallization and structural adjustment. However the quartz in near ore body rock didn't have enough hydrothermal influence, so it's not pure. Genealogy research technology is a useful technique for in-depth exploration of study area mineralization process and metallogenic regularity.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(11): 3061-5, 2013 Nov.
Artículo en Zh | MEDLINE | ID: mdl-24555381

RESUMEN

The results of Raman, SEM, CL and EDS analysis show that the quartz-type BIF (banded iron formation) in Tieshanmiao formation, from Wuyang area of south North China Craton mainly contains quartz, magnetite and a small quantity of calcite. In comparison, magnetites represent the highest automorphic degree, while calcites contribute to the lowest automorphic degree. In addition, the automorphic degree of the quartz lies between magnetite and calcite. In the results of Raman analysis, the crystallinity and order degree are quite diverse in the vertical direction of the calcite band-like, and this is different from the calcite vein precipitating from the upper hydrothermal fluid. There are obvious plastic flow happening to calcite particles. During the process of plastic flow, the calcites are finally filled in the space between quartz and magnetite. This is the reason why the cross sectional shape and distributional characteristics of calcite aggregate are controlled by the particles of quartz and magnetite, which is also evidenced by the calcite filled into the slight interspace between two particles of quartz. In the Raman analysis, there are apparent differences of microarea component in calcite band-like, and this denotes that it is produced by the plastic flow and concourse process. What's more, the calcite acts as the migration intermedium of tiny magnetite during their concourse and crystallization processes, which is witnessed by the concentrated particles of magnetite in small size in local parts of the calcites. With the help of calcite, the small magnetite particles join together to crystallize with bigger size or form aggregate of minerals.

9.
Pulm Pharmacol Ther ; 24(4): 434-41, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21501693

RESUMEN

Resolvin D1 (RvD1), an endogenous lipid molecule derived from docosahexaenoic acid (DHA), has been described to promote inflammatory resolution. The present study aimed to determine the protective effects and the underlying mechanisms of RvD1 on lipopolysaccharide (LPS)-induced acute lung injury (ALI). Pretreatment RvD1 to mice 30 min before inducing ALI by LPS decreased the mortality and improved lung pathological changes, inhibited LPS-induced increases in polymorphonulear and mononuclear leukocytes recruitment, total proteins content, tumor necrosis factor (TNF-α) and interleukin-6 (IL-6) production in the bronchoalveolar lavage fluids (BALFs). In addition, RvD1 markedly reduced LPS-induced the expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and adhesion molecules, as well as myeloperoxidase (MPO) activity. Moreover, RvD1 markedly inhibited LPS-induced the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-κB (NF-κB). Furthermore, pretreatment with Boc, a lipoxin A4 receptor (ALX) antagonist, significantly reversed these beneficial effects of RvD1 on LPS-induced acute lung injury in mice. Taken together, our study showed that RvD1 improved survival rate and attenuated ALI in mice induced by LPS, and the protective mechanisms might be related to selective reaction with ALX, which inhibits MAPKs and NF-κB pathway.


Asunto(s)
Lesión Pulmonar Aguda/prevención & control , Ácidos Docosahexaenoicos/uso terapéutico , Lipopolisacáridos/toxicidad , Lesión Pulmonar Aguda/enzimología , Lesión Pulmonar Aguda/etiología , Animales , Moléculas de Adhesión Celular/análisis , Dinoprostona/análisis , Recuento de Leucocitos , Pulmón/efectos de los fármacos , Pulmón/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , FN-kappa B/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo II/análisis , Peroxidasa/metabolismo
10.
Mar Drugs ; 8(7): 2212-22, 2010 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-20714433

RESUMEN

Spherical microparticles, capable of responding to magnetic fields, were prepared by encapsulating dextran-coated Fe3O4 nanoparticles into chitosan poly(acrylic acid) (PAA) microspheres template. The obtained magnetic microspheres were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and thermogravimetry (TG). The results showed that the microspheres were formed and demonstrated magnetic behavior in an applied magnetic field. In addition, magnetite particles were well encapsulated and the composite particles have high magnetite content, which was more than 40%.


Asunto(s)
Resinas Acrílicas/química , Quitosano/química , Magnetismo , Microesferas , Dextranos/química , Óxido Ferrosoférrico/química , Microscopía Electrónica/métodos , Nanopartículas , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Difracción de Rayos X
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(12): 3304-8, 2009 Dec.
Artículo en Zh | MEDLINE | ID: mdl-20210156

RESUMEN

Investigations of crystal habit, quality and defects analysis of natural diamond and HPHT synthetic diamonds from Fe-C(H) and Ni-C system by Raman and PL spectra indicate that most of the diamonds from Fe-C(H) system have an octahedral habit which is the main habit in natural diamond, while most of the diamonds from Ni-C system have a hexakisoctahedral habit. Because there are more photoluminescence centers in synthetic diamond from Ni-C system than that from Fe-C(H) system, and in synthetic diamond than in natural diamond, the quality of natural diamond is best though it forms in more polygenic environment, which suggested that during the process of diamond formation clearing "impurity" must occur. Therefore, the authors believe that not only the substance system variance but also time and space conditions for diamond formation should be considered when the authors try to probe into the relations of formation process between natural and HPHT synthetic diamonds.

12.
Eur J Pharmacol ; 587(1-3): 302-8, 2008 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-18420187

RESUMEN

Baicalin, a traditional anti-inflammatory drug, has been found to protect against liver injury in several experimental animal hepatitis models; however, the mechanisms underlying the hepatoprotective properties of baicalin are poorly understood. In the present study,we investigated the effects of baicalin on the acute liver injury in mice induced by Lipopolysaccharide/D-galactosamine (LPS/D-GalN). Baicalin (50, 150, and 300 mg/kg) was pretreated intraperitoneally (i.p.) at 2, 24, and 48 h respectively before LPS/D-GalN injected in mice. The mortality, hepatic tissue histology, hepatic tissue Tumor necrosis factor-alpha (TNF-alpha) and myeloperoxidase (MPO), plasma levels of TNF-alpha and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were analyzed. Besides, western blotting analyses of nuclear factor kappa B (NF-kappaB) translocation and Heme oxygenase-1(HO-1) protein expression, as well as HO-1 activity were determined. The results showed that baicalin protected against LPS/D-GalN-induced liver injury, including dose-dependent alleviation of mortality and hepatic pathological damage, decrease of ALT/AST release and the rise of MPO. Baicalin reduced nuclear translocation of NF-kappa B, TNF-alpha mRNA and protein levels in hepatic tissues and plasma levels of TNF-alpha induced by LPS/D-GalN. Moreover, baicalin dose-dependently increased HO-1 protein expression and activity. Further, inhibition of HO-1 activity significantly reversed the protective effect of baicalin against LPS/D-GalN-induced liver injury. These results suggest that baicalin can effectively prevent LPS/D-GalN-induced liver injury by inhibition of NF-kappa B activity to reduce TNF-alpha production and the underlying mechanism may be related to up-regulation of HO-1 protein and activity.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Flavonoides/farmacología , Galactosamina/antagonistas & inhibidores , Hemo-Oxigenasa 1/metabolismo , Lipopolisacáridos/antagonistas & inhibidores , Animales , Western Blotting , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Galactosamina/toxicidad , Lipopolisacáridos/toxicidad , Hígado/enzimología , Hígado/patología , Ratones , Ratones Endogámicos BALB C , Peroxidasa/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia Arriba/efectos de los fármacos
13.
Yao Xue Xue Bao ; 42(7): 698-703, 2007 Jul.
Artículo en Zh | MEDLINE | ID: mdl-17882951

RESUMEN

The study is to investigate the effect of asiaticoside on collagen-induced arthritis (CIA). The model of CIA mice was prepared and the change of secondary paw swelling and the arthritis scores were observed. In vitro proliferation of spleen cells was examined using MTT assay. The cell-free protein extracts from the arthritic joints and nonarthritic joints were used for the analysis of protein expression of cyclooxygenase-2 (COX-2). And the level of PGE2 in joints was assayed using PGE2 express EIA kit. The tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) levels in the serum were measured by ELISA. Histopathological examination was performed by hematoxylin-eosin (HE) stain method. Asiaticoside (10, 20 and 40 mg x kg(-1) x d(-1), 22 d, ig) significantly reduced paw swelling, and decreased the arthritis scores. There was a significant reduction in proliferation of spleen cells of CIA mice treated with asiaticoside as compared with that of untreated CIA mice. COX-2, PGE2, TNF-alpha and IL-6 production in CIA mice were inhibited by asiaticoside. Meanwhile, the pathological examination showed that articular cartilage degeneration with synovial hyperplasia and inflammatory cells infiltration in CIA mice was suppressed by asiaticoside. Its active mechanism may be related to inhibiting proliferation of lymphocyte and reduction of expression of COX-2 and inflammatory cytokines.


Asunto(s)
Articulación del Tobillo/patología , Artritis Experimental , Proliferación Celular/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Citocinas/metabolismo , Triterpenos/farmacología , Animales , Articulación del Tobillo/metabolismo , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Artritis Experimental/inducido químicamente , Artritis Experimental/metabolismo , Artritis Experimental/patología , Centella/química , Colágeno Tipo II , Citocinas/sangre , Dinoprostona/metabolismo , Interleucina-6/sangre , Linfocitos/patología , Masculino , Ratones , Ratones Endogámicos DBA , Plantas Medicinales/química , Bazo/patología , Triterpenos/aislamiento & purificación , Factor de Necrosis Tumoral alfa/sangre
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(6): 1066-70, 2007 Jun.
Artículo en Zh | MEDLINE | ID: mdl-17763758

RESUMEN

From the center to the rim of natural diamond there are differences in nitrogen and C-H bond contents, suggesting that diamond was formed under varying substance conditions. Both the nitrogen and C-H bond contents tend to decrease from the center to the rim as a whole, indicaing that nitrogen and hydrogen are expended little by little during the formation of diamond. But in the middle area of the sample both the nitrogen and C-H bond contents have a tendency to increase. This implies that nitrogen and hydrogen are added into the environment of diamond formation, meanwhile nitrogen is added earlier. So the procedure of diamond formation may be divided into three stages, namely nucleation and growth in the early stage, growth in the middle stage and in the late stage. In the early and late stages nitrogen and hydrogen are consumed in the environment of diamond formation. In the middle stage nitrogen and hydrogen must be replenished for the growth of diamond, and nitrogen should be replenished earlier than hydrogen. Hydrogen is useful to the nucleation and growth of diamond. During the formation of diamond the compounds of nitrogen and hydrogen do not exist. So we must avoid the formation of compounds of nitrogen and hydrogen for the nucleation and growth of diamond if we plan to introduce hydrogen to the synthesis of diamond at high temperature and high pressure (HPHT). Implanted hydrogen in graphite for the HPHT synthesis of diamond is a good choice.

15.
Oncol Lett ; 14(1): 63-72, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28693136

RESUMEN

Sphingosine kinase 1 (SPHK1) is a bioactive lipid mediator that has been identified as a biomarker in various cancers and is considered to play an important role in tumor progression. In the present study, the expression level of SPHK1 was examined in breast cancer clinical specimens, and its association with patient survival was investigated to clarify the clinical significance of SPHK1 in breast cancer. SPHK1 mRNA expression was increased in breast cancer tissues compared with that in matched adjacent breast tissues in 19 of 32 paired tissue specimens (59.4%). Immunohistochemical analysis of 122 breast cancer cases revealed that the expression levels of SPHK1 were upregulated in 64 tumor tissues (52.5%), and increased expression levels of the protein were significantly associated with the presence of lymph node metastasis (P=0.0016), number of positive lymph nodes (P=0.0268) and presence of distant metastasis (P=0.0097). Increased SPHK1 protein expression was also associated with human epidermal growth factor receptor 2 status (P=0.0100), initial symptoms (P=0.0025) and tumor location (P=0.0457). Patients with increased SPHK1 protein expression had shorter overall survival and disease-free survival times compared with patients with lower SPHK1. Univariate and multivariate analyses indicated that high SPHK1 expression may be a poor prognostic factor. These results indicated that SPHK1 may perform an important role in breast cancer and may be a predictive factor in patients with breast cancer.

16.
Oncol Rep ; 28(5): 1681-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22941407

RESUMEN

Multidrug resistance is one of the major causes limiting the efficacy of chemotherapeutic agents to control esophageal cancer. Herein, we investigated that the effect and mechanism of tetrandrine (TET) in the human esophageal squamous carcinoma cisplatin-resistant cell line YES-2/DDP. The human esophageal squamous carcinoma cisplatin-resistant cell line YES-2/DDP was isolated by stepwise selection in increasing concentrations of cisplatin. The CCK-8 method was carried out to measure the cell viability when cells were exposed to TET with or without cisplatin, and the IC50 and resistance index (RI) of cisplatin was then calculated. Real-time RT-PCR and western blotting were used to detect the mRNA and protein expression of multidrug resistance 1 (MDR1), multidrug resistance-associated protein 1 (MRP1) and breast cancer resistance protein (BCRP), respectively. Flow cytometry was adopted to determine CMFDA efflux and cell apoptosis, respectively. The resulting cell line YES-2/DDP was 16.4-fold resistant to cisplatin, the cytotoxicity of cisplatin to YES-2/DDP cells was enhanced by TET in a dose-dependent manner. Further, it was found that the expression of MDR1 and BCRP was similar in different treated cells. In contrast, the expression of MRP1 was markedly increased in YES-2/DDP cells, which was dose-dependently decreased by TET. In agreement with the results, MRP1 activity was also reversed by TET. In conclusion, TET possesses a reversal effect on drug resistance in YES-2/DDP cells through downregulation of MRP1, and has the potential to be an adjunct to chemotherapy for esophageal cancer.


Asunto(s)
Bencilisoquinolinas/farmacología , Carcinoma de Células Escamosas/metabolismo , Cisplatino/farmacología , Medicamentos Herbarios Chinos/farmacología , Neoplasias Esofágicas/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/biosíntesis , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/biosíntesis , Transportadoras de Casetes de Unión a ATP/genética , Antineoplásicos/farmacología , Apoptosis , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Neoplasias Esofágicas/patología , Humanos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo
17.
Phytomedicine ; 17(10): 811-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20171071

RESUMEN

Asiaticoside (AS), a triterpenoid product isolated from Centella asiatica, has been described to exhibit anti-in fl ammatory activities in several inflammatory models. However, the effects of AS on liver injury are poorly understood. The present study was undertaken to investigate whether AS is efficacious against Lipopolysaccharide (LPS) /D-galactosamine (D-GalN)-induced acute liver injury in mice and its potential mechanisms. AS (5, 10 and 20 mg/kg/d) was pretreated orally once daily for 3 days before LPS/D-GalN injected in mice. The mortality, hepatic tissue histology, plasma levels of Tumor necrosis factor-alpha (TNF-alpha) and alanine aminotransferase (ALT) and aspartate aminotransferase (AST), hepatic tissue TNF-alpha and caspase-3 activity were measured. Besides, western blotting analysis of phospho-p38 mitogen-activated protein kinase (phospho-p38 MAPK), phospho-c-jun N-terminal kinase (phospho-JNK) and phospho-extracellular signal regulated kinase (phospho-ERK) were determined. As a result, AS showed significant protection as evidenced by the decrease of elevated aminotransferases, hepatocytes apoptosis and caspase-3, alleviation of mortality and improvement of liver pathological injury in a dose-dependent manner. Further, we found that AS dose-dependently reduced the elevation of phospho-p38 MAPK, phospho-JNK, phospho-ERK protein and TNF-alpha mRNA expression in liver tissues and plasma TNF-alpha. These results suggest that AS has remarkable hepatoprotective effects on LPS/D-GalN-induced liver injury and the possible mechanism is related to inhibition of TNF-alpha and MAPKs.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Galactosamina/toxicidad , Lipopolisacáridos/toxicidad , Triterpenos/farmacología , Animales , Secuencia de Bases , Western Blotting , Cartilla de ADN , Sistema de Señalización de MAP Quinasas , Ratones , Ratones Endogámicos BALB C , Reacción en Cadena de la Polimerasa
18.
Int Immunopharmacol ; 10(3): 357-63, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20036342

RESUMEN

Fulminant hepatic failure (FHF) remains an extremely poor prognosis and high mortality; better treatments are urgently needed. Tetrandrine (TET), a traditional anti-inflammatory drug, has been reported to exhibit hepatoprotective activities in several liver injury models. We now investigated the effects and underlying mechanisms of TET on lipopolysaccharide (LPS) and D-galactosamine (D-GalN)-induced FHF in mice. TET (50, 100, and 200 mg/kg) was given intraperitoneally 1h before LPS/D-GalN injection in mice. The mortality and liver injury was evaluated subsequently. The results showed that administering TET to mice reduced mortality and improved liver injury induced by LPS/D-GalN in a dose-dependent manner. In addition, TET dose-dependently inhibited LPS/D-GalN-induced NF-kappaB activation, serum and hepatic tissues tumor necrosis factor-alpha (TNF-alpha) production, caspase-3 activation and hepatocellular apoptosis, myeloperoxidase (MPO) activity, intercellular adhesion molecule-1 (ICAM-1) and endothelial cell adhesion molecule-1 (ECAM-1) expression. Our experimental data indicated that TET might alleviate the FHF induced by LPS/D-GalN through inhibiting NF-kappaB activation to reduce TNF-alpha production.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Bencilisoquinolinas/farmacología , Galactosamina/inmunología , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/toxicidad , Fallo Hepático Agudo/inducido químicamente , Fallo Hepático Agudo/prevención & control , Animales , Apoptosis/efectos de los fármacos , Bencimidazoles , Western Blotting , Caspasa 3/metabolismo , Hepatocitos/efectos de los fármacos , Hipersensibilidad/patología , Hígado/enzimología , Hígado/patología , Fallo Hepático Agudo/patología , Pruebas de Función Hepática , Ratones , Ratones Endogámicos BALB C , Peroxidasa/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sobrevida , Factor de Transcripción ReIA/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
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