| 1. |
- Cao, Yong-Xiao, et al.
(författare)
-
Ligustilide induces vasodilatation via inhibiting voltage dependent calcium channel and receptor-mediated Ca(2+) influx and release.
- 2006
-
Ingår i: Vascular Pharmacology. - : Elsevier BV. - 1537-1891. ; 45:3, s. 171-176
-
Tidskriftsartikel (refereegranskat)abstract
- The purpose of the present study was to investigate the effect of ligustilide on vasodilatation in rat mesenteric artery and the mechanisms responsible for it. Isometric tension of rat mesenteric artery rings was recorded by a sensitive myograph system in vitro. The results showed that ligustilide at concentrations more than 10 mu M relaxed potassium chloride (KCl)-preconstricted rat mesenteric artery in a con centration-dependent manner. The vasodilatation effect of ligustilide was not dependent on endothelium. Ligustilide rightwards shifted concentration-response curves induced by KCl, calcium chloride (CaCl2), noradrenaline (NA) or 5-hydroxytryptamine (5-HT) in a non-parallel manner. This suggests that the vasodilatation effects were most likely via voltage-dependent calcium channel (VDCC) and receptor-operated calcium channel (ROCC). Propranolol, glibenclamide, tetraethylammonium and barium chloride did not affect the vasodilation induced by ligustilide, showing that beta-adrenoceptor, ATP sensitive potassium channel, calcium-activated potassium channel and inwardly rectifying potassium channel were not involved in the vasodilatation. Ligustilide concentration-dependently inhibited the vasoconstriction induced by NA or CaCl2 in Ca2+-free medium, indicating that the vasodilatation relates to inhibition of extracellular Ca2+ influx through VDCC and ROCC, and intracellular Ca2+ release from Ca2+ store. Since caffeine-induced contraction was inhibited by ligustilide, inhibition of intracellular Ca2+ released by ligustilide occurred via the ryanodine receptors. Our results suggest that ligustilide induces vasodilatation in rat mesenteric artery by inhibiting the VDCC and ROCC, and receptor-mediated Ca2+ influx and release. (c) 2006 Elsevier Inc. All rights reserved.
|
|
| 2. |
- He, G. S., et al.
(författare)
-
Stimulated Rayleigh-Bragg Scattering From a Two-Photon Absorbing CdSe-CdS-ZnS Quantum-Rods System : Optical Power Limiting and Phase-Conjugation
- 2008
-
Ingår i: IEEE Journal of Quantum Electronics. - : Institute of Electrical and Electronics Engineers (IEEE). - 0018-9197 .- 1558-1713. ; 44:9-10, s. 894-901
-
Tidskriftsartikel (refereegranskat)abstract
- This work reports the properties of stimulated Rayleigh-Bragg scattering (SRBS) from a two-photon absorbing CdSe-Cds-ZnS quantum-rods (QRs) solution in chloroform, excited by 1064-nm and similar to 13-ns laser pulses. The two-photon absorbing capability of the scattering medium, as well as the pump threshold, spectral structure, and pulse waveforms of the backward stimulated scattering were measured. Comparing to a pure solvent or an organic dye-solution, the semiconductor QR system has many advantages such as the lower pump threshold, higher energy transfer efficiency, and better photo-physical and photo-chemical stability. The measured output/input characteristic curve shows that the backward SRBS can enhance the optical power limiting performance that is based on two-photon absorption, backward stimulated scattering, and other nonlinear absorption mechanisms. In addition, the backward SRBS beam from our sample medium exhibits a fairly good optical phase-conjugation capability, so that the distortion influence from an inserted aberrator can be automatically removed.
|
|
| 3. |
|
|
| 4. |
- Hu, R., et al.
(författare)
-
Metallic Nanostructures as Localized Plasmon Resonance Enhanced Scattering Probes for Multiplex Dark-Field Targeted Imaging of Cancer Cells
- 2009
-
Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 113:7, s. 2676-2684
-
Tidskriftsartikel (refereegranskat)abstract
- In this paper, we report the use of bioconjugated gold nanorods and silver nanoparticles as targeted localized surface plasmon resonance enhanced scattering probes for dark-field multiplex and transmission electron microscopy (TEM) imaging of pancreatic cancer cells. We take advantage of the spectrally widely separated localized plasmon resonance of the gold nanorods and silver nanoparticles which produce wavelength selective plasmon resonance scattering to allow multiplex imaging with high contrast. When the surfaces are functionalized, aqueous dispersions of bioconjugated gold nanorods and silver nanoparticles are prepared. We demonstrate receptor-mediated delivery of bioconjugated gold nanorods and silver nanoparticles simultaneously into pancreatic cancer cells, using multiplexed dark-field microscopy technique. We also show that the bioconjugated metallic nanostructures can be used for high-contrast TEM imaging as well.
|
|
| 5. |
- Lewander, Andreas, 1973-, et al.
(författare)
-
Polymorphism in the promoter region of the NFKB1 gene increases the risk of sporadic colorectal cancer in Swedish but not in Chinese populations
- 2007
-
Ingår i: Scandinavian Journal of Gastroenterology. - : Informa UK Limited. - 0036-5521 .- 1502-7708. ; 42:11, s. 1332-1338
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. An insertion/deletion polymorphism (-94ins/delATTG) in the promoter region of the NFKB1 gene correlates to an increased risk of ulcerative colitis, a known risk factor for colorectal cancer, but this polymorphism has not been studied in colorectal cancer patients. The purpose of this study was to investigate whether this polymorphism is related to colorectal cancer risk and clinicopathological variables. Material and methods. Case samples were taken from four groups of Swedish patients: 193 unselected patients, 90 patients with ≥3 affected 1st-degree relatives, 85 patients with 2 affected 1st-degree relatives, and 109 sporadic cancer patients, and one group of 193 unselected Chinese patients. Controls included 439 Swedish and 458 Chinese healthy individuals. Genotypes were determined by polymerase chain reaction (PCR)-restriction fragment length polymorphism. Results. The deletion increased the risk of colorectal cancer among Swedish unselected patients (OR=3.81, 95% CI: 2.17-6.69, p<0.0001 for heterozygote deletion, and OR=4.65, 95% CI: 2.43-8.89, p<0.0001 for homozygote deletion) and sporadic cancer patients (OR=7.73, 95% CI: 3.06-19.57, p<0.0001 for heterozygote deletion, and OR=6.58, 95% CI: 2.35-18.43, p<0.0001 for homozygote deletion) compared to homozygote insertion (wild-type), but not among the other Swedish or Chinese patients (p>0.05). Similar evidence was seen in age-adjusted analyses (p<0.0001). The polymorphism did not correlate to clinicopathological variables (p>0.05). Conclusions. Deletion of the polymorphism was associated with increased susceptibility to sporadic colorectal cancers in the Swedish population, but not in the Swedish patients with a family history of colorectal cancer or in Chinese patients. © 2007 Taylor & Francis.
|
|
| 6. |
- Li, He, et al.
(författare)
-
Enhanced G-protein coupled receptors-mediated contraction and reduced endothelium-dependent relaxation in hypertension
- 2007
-
Ingår i: European Journal of Pharmacology. - : Elsevier BV. - 1879-0712 .- 0014-2999. ; 557:2-3, s. 186-194
-
Tidskriftsartikel (refereegranskat)abstract
- The present study was designed to demonstrate a hypothesis that some G-protein coupled receptors are up-regulated and a dysfunction of endothelium occurs in hypertension. The arteries from hypertensive patients and spontaneously hypertensive rats (SHR) were tested. An in vitro myograph system was used to obtain concentration-contraction curves mediated by endothelin ETA, endothelin ETB, 5-hydroxytryptamine 2A (5HT(2A))-receptors and alpha(1)-adrenoceptors in the arterial segments. In hypertensive patients, the maximum contractions (E-max) induced by endothelin ETB, endothelin ETA and 5-HT receptors were significantly increased with elevated pEC(50) values, while a significantly leftward shift of alpha(1)-adrenoceptor-mediated contraction was seen. Similar results were obtained in SHR. Specific antagonists for 5-HT2A receptors or alpha(1)-adrenoceptors rightward shifted the concentration-contractile curves induced by 5-HT or noradrenalin, while the Emax were not significantly altered, suggesting that the contractions were mediated by 5-HT2A receptors and ocl-adrenoceptors, respectively. Endothelium-dependent maximum relaxation (R-max) in the arterial segments induced by acetylcholine was significantly decreased in both hypertensive patients and SHR. In addition, nitric oxide- and endothelium-derived hyperpolarizing factor-mediated dilatations were decreased significantly and the arterial enclothelial cells were in part lost in SHR. In conclusion, endotheliD ETB, endothelin ETA, 5-HT2A receptor- and alpha-adrenoceptor-mediated contractions were increased in hypertension, while the endotheliurn and its ftinctions were damaged. (c) 2006 Elsevier B.V All rights reserved.
|
|
| 7. |
- Li, He, et al.
(författare)
-
Quantitative analysis of valiolamine through pre-column derivatization with phenylisocyanate using high-performance liquid chromatography with UV detection : Selection of reagent, identification of derivative and optimization of derivatization conditions
- 2009
-
Ingår i: Journal of Pharmaceutical and Biomedical Analysis. - : Elsevier. - 0731-7085 .- 1873-264X. ; 49:4, s. 957-963
-
Tidskriftsartikel (refereegranskat)abstract
- This report describes the improved quantitative determination of valiolamine in a medium for microbial culture using high-performance liquid chromatography with UV detection. Valiolamine aqueous solution was dried, dissolved in dimethyl sulfoxide and derivatization performances of phenylisocyanate (PHI), 1-fluoro-2,4-dinitrobenznene and 1-naphthylisothiocyanate were compared in the presence of triethylamine. The PHI was chosen as the most suitable derivatization reagent and the valiolamine-PHI derivative was identified by thin-layer chromatography and electrospray ionization mass spectrometry. The derivative eluted at 10.5 min on a reverse-phase column using a mobile phase composed of 10% acetonitrile in water containing 0.5 mM sodium octyl sulfate (pH 3.0), at a column flow rate of 1.0 mL/min with UV detection at 240 nm. The optimum conditions for derivatization were a reaction temperature of 30 degrees C, reaction time of 30 min, and PHI concentration higher than 33.6 mM. Calibration curves were linear in the range of 0.99-19.95 microg/mL for the standard solutions and 24.9-99.7 microg/mL for the spiked sample. The proposed method was validated and proven to be selective, accurate and precise and suitable for the quantitative analysis of valiolamine in medium for microbial cultures.
|
|
| 8. |
|
|
| 9. |
- Wu, Peng, et al.
(författare)
-
A novel methodology for synthesizing crystalline metallosilicates with expanded pore windows through molecular alkoxysilylation of zeolitic lamellar precursor
- 2008
-
Ingår i: Journal of the American Chemical Society. - : American Chemical Society. - 0002-7863 .- 1520-5126. ; 130:26, s. 8178-8187
-
Tidskriftsartikel (refereegranskat)abstract
- Postalkoxysilylation with diethoxydimethylsilane has been carried out on the zeolitic lamellar precursors of various topologies such as MWW, FER, CDO and MCM-47 aiming to construct new crystalline structures with expanded pore apertures between the layers. The silylation process and the crystalline and pore structures of the resulting materials have been investigated with the techniques of XRD, IR, 13C and 29Si MAS NMR, ICP, SEM, HRTEM, elemental analyses, and N2 adsorption. In contrast to forming known three-dimensional zeolite structures after direct calcination of the lamellar precursors, the silylation led to new crystalline structures with opener pores, as evidenced by the shift of layer-related diffractions to the lower-angle region in XRD patterns and the enlarged interlayer pores found by HRTEM images. After optimizing the treatment conditions, particularly the amount of silane agent, a maximum and homogeneous silylation was realized, which guaranteed the phase purity in interlayer expanded zeolites. The expanded structures were well preserved after calcination at 823 K or reflux in water for 1 to 2 weeks, indicating a high thermal stability and also a hydrothermal stability. The interlayer expanded zeolites prepared from the metallosilicate precursors of MWW topology exhibited higher catalytic activities in the redox and solid acid-catalyzed reactions of bulky molecules than that of their counterparts with conventional MWW topology.
|
|
| 10. |
|
|
