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121.
Radiolabeled molecules have an important role to evaluate tumor characteristics such as aggressiveness, and to identify the effectiveness of cancer treatments such as chemotherapy and radiotherapy. Various radionuclide (18F, 99mTc, 124I) labeled molecules can be used apoptosis detection by estimating decrescendos cell viability after therapy. 99mTc-tetrofosmin which is used as a myocardial perfusion imaging agent in routine and at the same time is known to accumulate in various tumors including breast tumor. The aim of this study was to assess the utility of 99mTc-tetrofosmin for monitoring the early response of MCF-7 breast cancer to chemotherapy. To evaluate the role of 99mTc-tetrofosmin in vitro chemotherapy, the uptake ratio was determined using MCF-7 breast cancer line after the cells had been treated with cisplatin. When we examined the apoptotic ratios which induced with different dose of cisplatin in MCF-7 breast cancer cells by using Annexin V and TUNEL methods, it was observed that the rate of apoptosis increased with soaring dose. The uptake rates of 99mTc-tetrofosmin in MCF-7 cell line in the chemotherapeutic groups were lower than it is in the control group (p < 0.01). The negative correlation between uptake ratios and apoptotic rates shows that 99mTc-tetrofosmin may be used a radiopharmaceutical for evaluating chemotherapy response. 99mTc-tetrofosmin might be probably useful as an imaging agent for estimation of early chemotherapy response in breast cancer.  相似文献   
122.
(1S,2S)-N1,N2-Bis(3-chlorobenzyl)cyclohexane-1,2-diamine 1a′ and (1S,2S)-N1,N2-bis(4-chlorobenzyl)cyclohexane-1,2-diamine 1b′ were used to prepare chiral Cu(II) complexes Cu-Y-1a, Cu-Y-1b, Cu-mZSM5-1a, and Cu-mZSM5-1b by a flexible ligand method using copper exchanged zeolite Y and mesoporous ZSM-5. The characterization of zeolite supported complexes was performed by microanalysis, IR-, diffuse reflectance spectroscopy (DRS), EPR spectroscopy, specific rotation and thermogravimetric analysis (TGA). The catalytic activity of these supported complexes was explored for the asymmetric nitroaldol reaction of various aldehydes with nitromethane at 0 °C. Excellent yields (up to 99%) of β-hydroxy nitroalkane with an ee of up to 94% were achieved in the case of benzaldehyde as substrate. Significantly, the performance of the supported catalyst was better in terms of enantioselectivity than the complex under homogenous conditions. The supported catalysts were recycled four times with no observable loss in performance and no leaching of the catalytically active complex during the nitroaldol reaction.  相似文献   
123.
Mesoporous silica-coated hollow manganese oxide (HMnO@mSiO(2)) nanoparticles were developed as a novel T(1) magnetic resonance imaging (MRI) contrast agent. We hypothesized that the mesoporous structure of the nanoparticle shell enables optimal access of water molecules to the magnetic core, and consequently, an effective longitudinal (R(1)) relaxation enhancement of water protons, which value was measured to be 0.99 (mM(-1)s(-1)) at 11.7 T. Adipose-derived mesenchymal stem cells (MSCs) were efficiently labeled using electroporation, with much shorter T(1) values as compared to direct incubation without electroporation, which was also evidenced by signal enhancement on T(1)-weighted MR images in vitro. Intracranial grafting of HMnO@mSiO(2)-labeled MSCs enabled serial MR monitoring of cell transplants over 14 days. These novel nanoparticles may extend the arsenal of currently available nanoparticle MR contrast agents by providing positive contrast on T(1)-weighted images at high magnetic field strengths.  相似文献   
124.
A series of 5-substituted-4-amino-1,2,4-triazole-3-thioesters was synthesized by converting variously substituted organic acids successively into the corresponding esters, hydrazides, 5-substituted-1,3,4-oxadiazole-2-thiols, 5-substituted-1,2,4-triazole-2-thiols and 5-substituted-1,3,4-oxadiazole-2-thioesters. Finally the target compounds were obtained by refluxing 5-substituted-1,3,4-oxadiazole-2-thioesters in the presence of hydrazine hydrate and absolute alcohol. The structures of the synthesized compounds were established by physicochemical and spectroscopic methods. The synthesized compounds were evaluated for their in vitro antifungal activity. Some of the evaluated compounds possessed significant antifungal activity as compared to a terbinafine standard.  相似文献   
125.
Characterization of a polymer library engineered to enhance their ability to protect and deliver their nucleotide cargo to the cells is reported. The ζ-potential continuously increased with higher polymer:siRNA weight ratio, and the ζ-potential of lipid-modified polymers:siRNA complexes were higher than PEI2 at all ratios. At polymer:siRNA ratio of 1:1, all lipid-substituted polymers showed complete protection against degradation. Lipid-modified polymers significantly increased the cellular uptake of siRNA complexes and down-regulation of GAPDH and P-gp (max. 66% and 67%, respectively). The results indicate that hydrophobic modification of low molecular PEI could render this otherwise ineffective polymer to a safe effective delivery system for intracellular siRNA delivery and protein silencing.  相似文献   
126.
Phenyl(trimethylsilylethynyl)iodonium and tert-butyldimethylsilylethynyl(phenyl)iodonium triflates were applied to alkynylation of benzotriazole. Treatment of the silylethynyliodonium triflates with the potassium salt of benzotriazole ion in (t)BuOH and CH(2)Cl(2) gave 2-(trimethylsilylethynyl)-2H-1,2,3-benzotriazole and 2-(tert-butyldimethylsilylethynyl)-2H-1,2,3-benzotriazole in 74% and 76% yields, respectively. The regioisomers, 1-silylethynyl-1H-1,2,3-benzotriazole derivatives, were minor. In both cases of the silyl-substitued ethynyliodonium salts, novel regioselective alkynylation of benzotriazole at the 2 position was observed.  相似文献   
127.
Thin films of MOFs grown on solid substrates offer a huge potential with regard to tailoring the properties of a surface, in particular if used in connection with post-synthesis modification (PSM). Here, we report on the PSM of surface-supported crystalline MOFs, with target molecules using an amine-based coupling strategy.  相似文献   
128.
In this study, the activities of four ginsenosides Rc, Re, Rd, and Rf on splenic lymphocytes growth were studied by microcalorimetry. Some qualitative and quantitative information, such as the metabolic power–time curves, growth rate constant k, maximum heat-output power of the exponential phase P max and the corresponding appearance peak time t max, total heat output Q t, and promotion rate R p of splenic lymphocytes growth affected by the four ginsenosides were calculated. In accordance with thermo-kinetic model, the corresponding quantitative relationships of k, P max, t max, Q t, R p, and c were established, . Also, the median effective concentration (EC50) was obtained by quantitative analysis. Based on both the quantitative quantity–activity relationships (QQAR) and EC50, the sequence of promotion activity was Rc > Re > Rd > Rf. The analysis of structure–activity relationships showed that the number, type, and position of sugar moieties on the gonane steroid nucleus had important influences on the promotion activity of Rc, Re, Rd, and Rf on splenic lymphocytes growth. Microcalorimetry can be used as a useful tool for determining the activity and studying the quantity–activity relationship of drugs on cell.  相似文献   
129.
A series of 1,3,5-triaryl-2-pyrazolines was synthesized by dissolving the corresponding 4-alkoxychalcones in glacial acetic acid containing a few drops of concentrated hydrochloric acid. This step was followed by the addition of (3,4-dimethylphenyl) hydrazaine hydrochloride. Finally the target compounds were precipitated by pouring the reaction mixture onto crushed ice. The structures of the synthesized compounds were established by physicochemical and spectroscopic methods. The 1,3,5-triaryl-2-pyrazolines bearing homologous alkoxy groups were found to possess fluorescence properties in the blue region of the visible spectrum when irradiated with ultraviolet radiation. The fluorescent behavior of these compounds was studied by UV-Vis and emission spectroscopy, performed at room temperature.  相似文献   
130.
A three-channel spectrometer (3CS) based on a commercial digital camera was developed to distinguish among tens of large (>100 nm), anisotropic plasmonic particles with various shapes, orientations, and compositions on a surface simultaneously. Using band pass filters and polarizers, the contrast of 3CS images could be enhanced to identify specific orientation and composition characteristics of gold and gold-silver nanopyramids and as well as the direction of the longest arm of gold nanostars.  相似文献   
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