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91.
ABSTRACT: BACKGROUND: Renilla Luciferase reporter gene (rLuc) GL4.82 and GL4.13 promoter are key player in transfection, but precise knowledge of its targets in colon cancer remains limited. The aim of this study was to characterize the best transfection technique to produce a stable transfected colon DLD1 (colorectal adenocarcinoma cell line), therefore imaging based approaches were employed. RESULTS: DLD1 cells were transfected with a Plasmid (SV40-RLuc) carrying Renilla luciferase under the control of the SV-40 promoter, by using two different transfection techniques. Cells expressing the required DNA were isolated after antibiotic (Puramycin) selection. Clones of DLD-1/SV40-RLuc were produced using two different techniques (96 well plates and Petri dish) and their florescence intensity was recorded using IVIS machine (Calliper Life Sciences, Hopkinton, USA). Both techniques were characterized with the help of serial dilution technique. Results from this study substantiated that electroporation is the best. As expected, clones varied in their specific luciferase activity along with the dilutions. With the increase in cell concentration increase in intensity of florescence was recorded. CONCLUSIONS: Based on the results we are confident that this transfected cell line DLD-1/SV40-RLuc (colorectal adenocarcinoma cell line) is the best for further Orthotopic Xenotransplantation Studies and in-vivo experiments as well. Investigation shows that DLD1/SV-rLuc cells have gained little bit resistance against both drugs therefore further study is suggested to know the reasons. 相似文献
92.
Mabkhot YN Al-Majid AM Alamary AS Warad I Sedigi Y 《Molecules (Basel, Switzerland)》2011,16(6):5142-5148
Facile and convenient syntheses of bisdimethylthieno[2,3-b]thiophen-2,5-diyl bis(oxazole-2-amine), bis(1H-imidazol-2-amine), bis((3a)-H-indole),[1,2-a]pyrimidine), bis(1H-imidazo[1,2-b][1,2,4]triazole) and bis(9H-benzo[d]imidazo[1,2-a]imidazole) derivatives incorporating a thieno[2,3-b]thiophene moiety from the versatile and readily accessible 1,1'(3,4-dimethylthieno[2,3-b]thiophene-2,5-diyl)-bis(2-bromo-ethanone) (1) are described. 相似文献
93.
Many problems arising in practical applications lead to linear programming problems. Hence, they are fundamentally tractable. Recent interior-point methods can exploit problem structure to solve such problems very efficiently. Infeasible interior-point predictor–corrector methods using floating-point arithmetic sometimes compute an approximate solution with duality gap less than a given tolerance even when the problem may not have a solution. We present an efficient verification method for solving linear programming problems which computes a guaranteed enclosure of the optimal solution and which verifies the existence of the solution within the computed interval. 相似文献
94.
Lakhera Shradha Rana Meenakshi Devlal Kamal Celik Ismail Yadav Rohitash 《Structural chemistry》2022,33(3):703-719
Structural Chemistry - Tridax procumbens is a flowering plant of the Asteraceae family with a wide range of medicinal uses like anti-inflammatory, anti-diabetic, anti-microbial, immunomodulatory,... 相似文献
95.
Topcuoglu Bulent Ozmen Suleyman Fatih Boztosun Ismail Gulludag Cevdet Bertan 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):783-797
Journal of Radioanalytical and Nuclear Chemistry - In this study, natural (226Ra, 232Th, 40K) and artificial (137Cs) radionuclide activity concentration levels of 63 greenhouse soils collected from... 相似文献
96.
M. Ismail A. Farraga H. A. Abdusalam Th. El-Sherbini 《International Journal of Theoretical Physics》2004,43(1):111-125
The scattering of electrons by atomic copper has been studied using Born approximation and the concept of the generalized oscillator strength (GOS). Differential and total cross-sections for the excitation of the 3d10 4p2 P state are calculated at incident energies of 100 eV and are compared with other available experimental and theoretical data. The agreement between our calculation for the differential cross-section and the available experimental results is fairly good at the forward angles, while the agreement at large angles is poor. The calculated total cross-sections are compared with the experimental data and those predicted by several theories. It is found that our calculation for the total cross-sections are in a good agreement with the close coupling calculation of Msezane and Henry (1986a, Physical Review A
33, 1631) for incident energies greater than 20 eV. The integrated cross-section measurements of Ismail and Teubner (1995, Journal of Physics B: Atomic, Molecular and Optical Physics
28, 4164) are in good agreement with the present calculation. 相似文献
97.
W. M. Z. Wan Yunus A. B. Salleh A. Ismail K. Ampon C. N. A. Razak M. Basri 《Applied biochemistry and biotechnology》1992,36(2):97-105
Poly(methyl methacrylate) (PMMA) was found to be suitable for the immobilization of lipase fromCandida rugosa. The best result based on hydrolytic activity was obtained by adsorption of the purified unbuffered enzyme solution onto PMMA beads without any modification of the beads. Prolonged exposure of the protein to the beads increased its adsorption but the expressed activity decreased after 1 h of exposure. The magnitude of the immobilized activity also varied with the size of the beads. Immobilization of the lipase shifted its optimal reaction temperature from 37 to 45°C. The immobilized enzyme is also more stable than the free enzyme in solution. The operational half-life of the immobilized lipase packed in a column and assayed in a closed system is 40 d. 相似文献
98.
99.
In this work, we study the effect of concentration, host medium, PH and phase states on the fluorescence emission from the
laser dye Rhodamine B pumped by UV laser as exited source. The polymethylmethacrylate PMMA is used as a host medium in case
of solid phase samples while, ethanol and Tetrahydrofuran (THF) are used in case of a liquid one. Laser Induced Fluorescence
(LIF) technique was used to study the fluorescence properties of both cases of liquid and thin film solid-state samples. In
addition, the Dual Thermal Lens (DTL) technique was used to study the quantum yield of these samples. The concentrations of
Rhodamine B in ethanol as solvent between 2 × 10−2 M and 5 × 10−6 M were studied. The maximum fluorescence emission is observed at concentration of Rhodamine B C = 3 × 10−4 M. Comparison studies were investigated for different host medium such as ethanol, THF, PMMA in liquid phase state and PMMA
in solid phase state. The measurements revealed that, the behavior of both phases state was analogous. Rhodamine B/PMMA thin
film sample by ratio of 4:1 and thickness 0.12 mm was found to have the best photostability sample with a quantum yield about
≈0.82. 相似文献
100.