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751.
Background: Colorectal cancer (CRC) is one of the most common cancers worldwide. One of its subtypes is associated with defective mismatch repair (dMMR) genes. Saffron has many potentially protective roles against colon malignancy. However, these roles in the context of dMMR tumors have not been explored. In this study, we aimed to investigate the effects of saffron and its constituents in CRC cell lines with dMMR. Methods: Saffron crude extracts and specific compounds (safranal and crocin) were used in the human colorectal cancer cell lines HCT116, HCT116+3 (inserted MLH1), HCT116+5 (inserted MSH3), and HCT116+3+5 (inserted MLH1 and MSH3). CDC25b, p-H2AX, TPDP1, and GAPDH were analyzed by Western blot. Proliferation and cytotoxicity were analyzed by MTT. The scratch wound assay was also performed. Results: Saffron crude extracts restricted (up to 70%) the proliferation in colon cells with deficient MMR (HCT116) compared to proficient MMR. The wound healing assay indicates that deficient MMR cells are doing better (up to 90%) than proficient MMR cells when treated with saffron. CDC25b and TDP1 downregulated (up to 20-fold) in proficient MMR cells compared to deficient MMR cells, while p.H2AX was significantly upregulated in both cell types, particularly at >10 mg/mL saffron in a concentration-dependent manner. The reduction in cellular proliferation was accompanied with upregulation of caspase 3 and 7. The major active saffron compounds, safranal and crocin reproduced most of the saffron crude extracts’ effects. Conclusions: Saffron’s anti-proliferative effect is significant in cells with deficient MMR. This novel effect may have therapeutic implications and benefits for MSI CRC patients who are generally not recommended for the 5-fluorouracil-based treatment.  相似文献   
752.
A simple, sensitive and efficient spectrophotometric method is proposed for rapid determination of uranium using arsenazo-III in perchloric acid. The reaction between arsenazo-III and U(VI) was instantaneous in 3 mol L−1 HClO4. N-cetyl-N,N,N-trimethylammonium bromide was used for increasing the sensitivity and selectivity of the complex. The absorbance remains stable for over 48 h in the presence of surfactant. The method allows the determination of uranium in the range of 1–20 μg g−1 with a molar absorptivity of 3.9 × 105 dm3 mol−1 cm−1 at 681 nm. Sandell’s sensitivity of the complex was calculated to be 6.4 ng cm−2 at λmax 681 nm. A significant enhancement was achieved in the sensitivity of the proposed method whereas, Relative Standard Deviation was reduced from 4.5 to 1.7% in the presence of surfactant. Among various diverse ions studied, fluoride, cyanide, citrate, sulfate and phosphate interfere beyond the tolerance limit. Among cations only Cr3+ and Co2+ decreased the normal absorbance. The validity of the reported method was tested by determining uranium in the environmental water samples and Standard Reference Material. The results agreed closely with the reported values. The proposed method is new, easy in operation and better in sensitivity than many of the existing methods.  相似文献   
753.
Condensation of di-2-pyridyl ketone with S-methyldithiocarbazate or S-benzyldithiocarbazate yields potentially bridging ligands of the form Py2CNNHC(S)SR; Hdpksme (R = Me; the di-2-pyridyl ketone Schiff base of S-methyldithiocarbazate) and Hdpksbz (R = Bz; the di-2-pyridyl ketone Schiff base of S-benzyldithiocarbazate). Complexation of these ligands with Cu(II) in a 1:1 M ratio leads to the formation of dinuclear complexes of the general formula [Cu(NNNS)X]2 (X = Cl, NO3, H2O). X-ray crystallographic structure determinations show that each ligand provides three donor atoms (NNS) in a meridional configuration to one metal, viz. one of the pyridine nitrogen atoms, the azomethine nitrogen atom and the thiolate sulfur, while the nitrogen atom of the second pyridyl group forms a bridge to another copper(II) ion within the dimer. The coordination geometry around each copper(II) ion is approximately square pyramidal, the basal plane of which is composed of one of the pyridine nitrogen atoms, the azomethine nitrogen atom and a chlorido, nitrato or aqua ligand. The apical position of the square pyramid is always occupied by the pyridine nitrogen atom of the second ligand.  相似文献   
754.
The potentially pentadentate chelate 2,6-diacetylpyridine-bis(N-methyl-S-methyldithiocarbazate) (Nmedapsme) has been synthesized and structurally characterized by X-ray diffraction. Its reactions with nickel(II) salts did not lead to pentadentate coordinated ligand complexes but ternary complexes of general formula, [Ni(Nmedapsme)(nmesme)L]X·H2O (L = Br, I; X = I, BF4) where Nmedapsme binds as a tridentate and nmesme = N-methyl-S-methyldithiocarbazate. The related ternary nickel(II) complexes of formula, Ni(Nmedapsme)(nmetsc)Br2 has also been prepared and characterized. X-ray crystal structures of [Ni(Nmedapsme)(nmesme)I]I·H2O and [Ni(Nmedapsme)(nmesme)Br]BF4·H2O revealed that, in these complexes, the Nmedapsme ligand acts as a tridentate NNN donor while the distal S-donors are not coordinated. The bidentate (NS) ligand, nmesme coordinates to the nickel(II) ion via the amino nitrogen and the thione sulfur atoms, the sixth coordination site is occupied by an anion. In both complexes, the nickel(II) ion adopts a distorted octahedral configuration. The complex [Cu(nmesme)2(ONO2)]NO3 was obtained from an unsuccessful attempt to complex copper(II) with Nmedapsme. Hydrolysis of the parent Schiff base Nmedapsme occurred during complexation. An X-ray crystallographic structure analysis shows that the complex, [Cu(nmesme)2(ONO2)]NO3 has an approximately square-pyramidal geometry with the two nmesme ligands coordinated to the copper(II) ion as NS bidentate chelating agents via the amino nitrogen and thione sulfur atoms and the fifth coordination position of copper(II) is occupied by a monodentate nitrate ligand.  相似文献   
755.
Several derivatives of substituted 1,2,4‐triazole bearing the pyrazole (or oxadiazole) ring were synthesized via the reaction of 2,4‐dihydro‐4‐benzyl‐5‐(isomeric pyridyl)‐3H‐1,2,4‐triazole‐3‐thione 1a , 1b , 1c with ethyl chloroacetate, hydrazine hydrate, and acetyl acetone (or CS2/KOH) in absolute ethanol. The intermediate then undergoes an intramolecular cyclization in acidic medium. The newly synthesized compounds 4a , 4b , 4c to 7a , 7b , 7c were characterized using IR, NMR, and MS Spectroscopy. Some of the synthesized compounds 4 , 5 , 7a , 7b , 7c were evaluated for their antibacterial and antifungal activities. Most of these compounds indicated activity comparable to Gentamycine. Also some of them are more active than Tolnaftate, a known antifungal drug. J. Heterocyclic Chem., (2011)  相似文献   
756.
Pentafluorophenylammonium triflate (PFPAT) is used as an efficient catalyst in the von Pechmann condensation of phenols with β-ketoesters leading to the formation of coumarin derivatives. Short reaction times, easy and quick isolation of the products, excellent chemoselectivity, excellent yields and ease of catalyst recovery with consistent activity makes this protocol efficient and environmentally benign.  相似文献   
757.
Gene expression analysis is considered to be extremely important in many different biological researches. DNA-based diagnostic test, which contributes to DNA identification, has higher specificity, cost, and speed than some biochemical and molecular methods. In this study, we try to use the novel nano technology approach with Multiplex RT-PCR and Gold nano particular probes (GNPs-probes) in order to get gene expression in Curcumas melons. We used Agrobacterium tumefactions for gene transfer and GUS reporter gene as a reporter. After cDNA synthesis, Multiplex PCR and Multiplex RT-PCR techniques were used. Finally, probes were designed for RNA of GUS and Actin genes, and then the analysis of the gene expression using the probes attached to GNPs was carried out and the color changes in the GNPs were applied. In the following, probes hybridization was checked with DNA between 400 to 700 nm wavelengths and the highest rate was observed in the 550 to 650 nm. The results show that the simultaneous use of GNP-attached detectors and Multiplex RT-PCRcan reduce time and costmore considerably than somelaboratory methods for gene expiration investigation. Additionally, it can be seen thatthere is an increase in sensitivity and specificity of our investigation. Based on our findings, this can bea novel study doneusingMultiplex RT-PCRand unmodified AuNPs for gene transfer and expression detection to plants. We can claim that this assay has a remarkable advantage including rapid, cost-effectiveness, specificity and accuracy to detect transfer and expression genes in plants. Also,we can use this technique from other gene expressionsin many different biology samples.  相似文献   
758.
The improved F-expansion method is a rising approach to obtain new and broad-spectrum exact solutions to the nonlinear evolution equations in the field nonlinear sciences. In this study, the influential F-expansion method is used to extract the analytical solutions of the nonlinear Klein–Gordon equation with the aid of symbolic computation software Maple. We successfully establish the solutions in the form of hyperbolic, trigonometric and rational function structure. The derived solutions could be imperious and significant for narrating the physical phenomena in the real-world. For suitable values of the parameter involved in the solutions, we depict the 2D and 3D graphs of some obtained exact solutions.  相似文献   
759.
Voriconazole (VRC) is a broad-spectrum antifungal agent belonging to BCS class II (biopharmaceutical classification system). Despite many efforts to enhance its solubility, this primary issue still remains challenging for formulation scientists. Transethosomes (TELs) are one of the potential innovative nano-carriers for improving the solubility and permeation of poorly soluble and permeable drugs. We herein report voriconazole-loaded transethosomes (VRCT) fabricated by the cold method and followed by their incorporation into carbopol 940 as a gel. The prepared VRCT were evaluated for % yield, % entrapment efficiency (EE), surface morphology, possible chemical interaction, particle size, zeta potential, and polydispersity index (PDI). The optimized formulation had a particle size of 228.2 nm, a zeta potential of −26.5 mV, and a PDI of 0.45 with enhanced % EE. Rheology, spreadability, extrudability, in vitro release, skin permeation, molecular docking, antifungal, and antileishmanial activity were also assessed for VRCT and VRC loaded transethosomal gel (VTEG). Ex-vivo permeation using rat skin depicted a transdermal flux of 22.8 µg/cm2/h with enhanced efficiency up to 4-fold. A two-fold reduction in inhibitory as well as fungicidal concentration was observed against various fungal strains by VRCT and VTEG besides similar results against L-donovani. The development of transethosomal formulation can serve as an efficient drug delivery system through a topical route with enhanced efficacy and better patient compliance.  相似文献   
760.
A series of N-substituted saccharins namely 2-(1,1-dioxido-3-oxobenzo[d]isothiazol-2(3H)-yl) acetonitrile (2) and (alkyl 1,1-dioxido-3-oxobenzo[d]isothiazol-2(3H)-yl) acetate (3a–g) were synthesized, in moderate to excellent yields, from commercially available starting materials by two different approaches and their chemical structures were characterized by spectroscopic techniques (1H-NMR, 13C-NMR, IR, and MS). All the synthesized compounds were evaluated for their anti-inflammatory toward IL-6 and TNF-α, antioxidant, as well as their anticancer activities against hepatic cancer cells. In addition, their anti-fungal and antibacterial activities against both Gram-positive and Gram-negative bacteria were tested. All the tested compounds have exhibited excellent (3a, d, e) to moderate anti-inflammatory activity. Additionally, esters (3b, f) and nitrile (2) showed excellent antioxidant activity. Furthermore, ester 3f, with isopropyl ester, exhibited the highest cytotoxic activity compared to the other esters. Moreover, all compounds were evaluated as selective inhibitors of the human COX-1 enzyme using molecular docking by calculating the free energy of binding, inhibition constant, and other parameters to find out the binding affinity. The molecular study showed that esters (3d, f) and nitrile (2) revealed the highest binding affinities, hence enhancing the inhibition activity with the active site of the COX-1 enzyme. All the tested compounds have more negative Gibbs free, electrostatic, and total intermolecular energies than the standard inhibitor ASA. These results indicate that, all the tested sultams are potent anti-inflammatory drugs as compared to standard inhibitors. Finally, the chemical properties and the quantum factors of synthesized sultams were calculated based on density functional theory (DFT) to predict reactivity, and then correlated with the experimental data. Ester 3f showed the lowest ionization potential and lowest energy gap (Egap = 7.5691 eV), which was correlated with its cytotoxic activity. Furthermore, the spatial electron distribution of HOMO, LUMO were computed and it clearly indicates the electron donation ability of all the tested compounds.  相似文献   
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