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Cindy Strehl Timo Gaber Manuela Jakstadt Martin Hahne Paula Hoff Cornelia M. Spies Alexander Scheffold Gerd-Rüdiger Burmester Frank Buttgereit 《Journal of fluorescence》2013,23(3):509-518
Flow cytometry has become a widely-used and powerful tool for the characterization of cells according to their expression of specific proteins. However, sensitivity of this method is still limited since conventionally labeled antibodies can be conjugated with at maximum 1–10 dye molecules. This fact resulted in the need to develop new techniques in order to identify molecules which are expressed in very low but functionally relevant amounts. In the past, we have successfully used a liposome-based high-sensitivity immunofluorescence technique to measure the expression of low abundant membrane bound glucocorticoid receptors (mGR) on different cell types. The use of this technique allows the detection of as few as 50–100 antigen molecules per cell which is due to a 100-fold to 1000-fold increase in fluorescence signal intensity compared with conventional methods. The higher sensitivity is achieved since thousands of dye molecules can be enclosed in liposomes. Another modern high-sensitivity immunofluorescence staining method is the purchasable Fluorescence Amplification by Sequential Employment of Reagents (FASER) procedure. Here, we aimed at comparing sensitivity and specificity of these two techniques for the detection of the mGR. Our data demonstrate the FASER technique to be more sensitive and also more specific for the detection of mGR as compared to the liposome technique. However, both methods have advantages and disadvantages which are discussed in detail. 相似文献
23.
New carbohydrazone ligand derived from the condensation of carbohydrazide and ethyl acetoacetate, diethyl 3,3′‐(carbonylbis (hydrazin‐2‐yl‐1‐ylidene))(3E,3′E)‐dibutyrate (H4EBC), and its divalent Co, Ni and Cu chelates have been isolated and characterized utilizing convenient methods. 1H‐NMR spectrum of H4EBC revealed the abundance of the enol isomer in solution, which was the opposite to what was shown by the solid IR. This was supported by comparing the theoretical IR of both keto and enol forms. In [Ni(H4EBC)Cl2(H2O)]·2H2O, H4EBC acts as a neutral NON tridentate ligand via the (C=O)carbonyl oxygen atom besides the two (C=N)azomethine nitrogen atoms, while in [Co(H4EBC)Cl2(2H2O)]·2H2O, H4EBC behaves as a neutral NN bidentate ligand through the two azomethine groups. Magnetic measurements inherent to their electronic spectra show that both Ni (II) and Co (II) chelates have octahedron coordination frameworks. On the other hand, the ligand behaves as a binegative tetradentate in [Cu2(H4EBC)Cl2]·H2O via the deprotonated (C=O)carbonyl groups of the ethyl acetoacetate framework and the two (C=N)azomethine groups. In the latter complex, the carbonyl group of the carbohydrazide moiety is converted to hydroxyl group. Cu (II) complex has a tetrahedral geometry according to ESR and electronic spectral data. The reaction of H4EBC with SmCl3·6H2O or LnCl3·7H2O gave single crystals of abnormal product (C16H16N4O4). The packing diagram of this crystal has a chain structure. The photoluminescence spectra of [Cu 2 (H 4 EBC)Cl 2 ]·H 2 O , [Co(H 4 EBC)Cl 2 (H 2 O) 2 ]·2H 2 O and [Ni(H 4 EBC)Cl 2 (H 2 O)]·2H 2 O display emission broad‐bands at 342, 321 and 337 nm, respectively. The microbial behavior of the synthesized moieties was investigated against various bacterial and fungal strains. [Cu2(H4EBC)Cl2]·H2O complex shows the same activity as ampicillin towards Escherichia coli and Staphylococcus aureus with inhibition zones of 26 and 22 mm, respectively. Antioxidant activity is determined using bleomycin‐dependent DNA damage assay besides erythrocyte hemolysis. Finally, in vitro cytotoxic activities against two different cell lines have been examined. 相似文献
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A One‐Pot Synthesis of N‐Aryl‐2‐Oxazolidinones and Cyclic Urethanes by the Lewis Base Catalyzed Fixation of Carbon Dioxide into Anilines and Bromoalkanes
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Teemu Niemi Dr. Jesus E. Perea‐Buceta Dr. Israel Fernández Otto‐Matti Hiltunen Vili Salo Sari Rautiainen Dr. Minna T. Räisänen Prof. Timo Repo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10355-10359
The multicomponent assembly of pharmaceutically relevant N‐aryl‐oxazolidinones through the direct insertion of carbon dioxide into readily available anilines and dibromoalkanes is described. The addition of catalytic amounts of an organosuperbase such as Barton's base enables this transformation to proceed with high yields and exquisite substrate functional‐group tolerance under ambient CO2 pressure and mild temperature. This report also provides the first proof‐of‐principle for the single‐operation synthesis of elusive seven‐membered ring cyclic urethanes. 相似文献
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Dietrich Gudat Asadollah Haghverdi Timo Gans-Eichler Martin Nieger 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1637-1640
The high intrinsic stability of 1,3,2-diazaphospholenium cations enhances ionic polarization of covalent P--X bonds in P -halogeno- and P -hydrido-diazaphospholenes. The physical properties of the latter suggest a hydridic nature of the P--H bond, and their reactivities display an "Umpolung" as compared to known reaction patterns of phosphines. 相似文献
28.
Hatem M. Gaber 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):417-424
Several new pyrrolopyrazoles were synthesized via the reactions of each of 2-thiophenecarboxaldehyde thiazolonylhydrazone or 2-furaldehyde thiazolonylhydrazone with N -substituted maleimides followed by partial dehydogenation using bromobenzene and complete aromatization using nitrobenzene. Structures were established on the basis of elemental analyses and spectroscopic data studies. 相似文献
29.
Wagnat W. Wardakhan Hatem M. Gaber Salama A. Ouf Sherif M. Sherif 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):601-618
Abstract Heterocyclic enamines1 reacted with ethyl acetoacetate to afford the corresponding amide derivatives2. Treatment of2 with carbon disulphide yielded the dipotassium salts3which reacted in-situ with a variety of α -haloketones to give the respective substituted thiophenes5,8, and13. The reactivity of the latter products towards various chemical reagents was studied to yield their fused thiophene derivatives7,10,12, and14, respectively. Some representative compounds were tested for antimicrobial activity. 相似文献