Three new diarylheptanoids, designated 1-(3,4-dihydroxyphenyl)-7-(4-hydroxyphenyl)-(6E)-6-hepten-3-ol (1), 1-(3-hydroxyphenyl)-7-(3,4-dihydroxyphenyl)-3-methoxy-(6E)-6-heptene (2), (3R, 5R)-1-(3,4-dihydroxyphenyl)-7-phenyl-heptane-3,5-diol (3) and three known compounds, were isolated from rhizomes of Curcuma comosa. Structures of the compounds were determined by spectroscopic data analysis. 相似文献
The thiourea based receptor containing naphthalene groups (1), has been successfully designed and synthesized for application as an oxalate receptor. A density functional theory at B3LYP/6-31G(d,p)
level of theory has been applied to predict the binding ability between 1 and selected anions, i.e., oxalate, malonate, succinate, glutarate, dihydrogen phosphate, and hydrogen sulphate. Calculation results point out that
receptor 1 shows the strongest interaction to oxalate ion with the binding free energy of 172.48 kcal mol−1. The recognition ability of 1 to the selected anions has been also investigated by means of the absorption and emission techniques. Experimental results
are in excellent agreement with the calculation data in which receptor 1 shows highly selective for oxalate ion over the other anions with logβ of 3.82 (0.02) M−1 by means of the size of binding cavity.
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Two BODIPY derivatives for Cu2+ ion chemosensors containing 4-[2-(diethylamino)-2-oxoethoxy]phenyl (BDP1) and 3,4-bis[2-(diethylamino)-2-oxoethoxy]phenyl (BDP2) were synthesized by coupling appropriate N,N-diethyl-2-(4-formylphenoxy)acetamide and 2,4-dimethylpyrrole moieties in the presence of trifluoroacetic acid and anhydrous dichloromethane at room temperature. The binding abilities between these chemosensors and 50 equivalents of Na+, K+, Ag+, Ca2+, Fe2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+ and Pb2+ ions were studied using UV-vis and fluorescence spectrophotometry. The results show that, compared to other ions, both the UV-vis absorption and fluorescence emission intensity of BDP2 decreased dramatically when Cu2+ ion was added. To explain this behavior, ab initio quantum chemical calculations were performed using correlated second-order Møller-Plesset perturbation theory (MP2/LanL2DZ). The calculated orbital energies indicated that the decrease in UV-vis absorption intensity and the quenching of fluorescene emission were due to the single-electron reduction of Cu2+ to Cu+ ion.
Figure
Optimized structure, fluorescent spectra, frontier orbital energy diagrams and electron-transfer paths in receptor BDP2 before and after attachment to Cu2+ ion 相似文献
Background: Cigarette smoke induces inflammation and remodels immune response. Genetic and epigenetic alterations might be involved in the pathogenesis of smoking related diseases. In this study, we investigated the effect of smoking on systemic inflammation biomarkers and epigenetic changes at microRNA (miRNA) expression level. We also examined if the levels of inflammatory biomarkers were associated with selected single nucleotide polymorphisms (SNPs).
Method: From 39 smokers and 101 non-smokers, levels of total white blood cells (WBCs) and its subpopulations, plasma cytokines/chemokines/proteins and miRNAs were analysed. For three biomarkers, C-reactive protein (CRP), MCP-1 and IFN-γ that were affected by smoking, the influence of SNPs was analyzed.
Result: Elevated levels of total WBCs, neutrophils, monocytes, lymphocytes, CRP, MCP-1, IFN-γ and lower levels of miR-21 were detected in smokers. The elevated levels of IFN-γ in smokers was only statistically significantly associated with rs2069705 AG/GG SNP-genotype.
Conclusions: A lower level of oncomir miRNA-21 and a higher level of immune modelling cytokine IFN-γ detected in smokers could be a protective immune response to cigarette smoke. The higher level of IFN-γ in smokers with a specific SNP genotype also suggests that a genetic interaction with smoking might predict the pathobiology of smoking related disease. 相似文献
The progression of normal cells through the cell cycle is meticulously regulated by checkpoints guaranteeing the exact replication of the genome during S-phase and its equal division at mitosis. A prerequisite for this achievement is synchronized DNA-replication and centrosome duplication. In this context the expression of cyclins A and E has been shown to play a principal role.
Results
Our results demonstrated a correlation between centrosome amplification, cell cycle fidelity and the level of mRNA and protein expression of cyclins A and E during the part of the cell cycle defined as G1-phase by means of DNA content based histogram analysis. It is shown that the normal diploid breast cell line HTB-125, the genomically relatively stable aneuploid breast cancer cell line MCF-7, and the genomically unstable aneuploid breast cancer cell line MDA-231 differ remarkably concerning both mRNA and protein expression of the two cyclins during G1-phase. In MDA-231 cells the expression of e.g. cyclin A mRNA was found to be ten times higher than in MCF-7 cells and about 500 times higher than in HTB-125 cells. Topoisomerase II α showed high mRNA expression in MDA compared to MCF-7 cells, but the difference in protein expression was small. Furthermore, we measured centrosome aberrations in 8.4% of the MDA-231 cells, and in only 1.3% of the more stable aneuploid cell line MCF-7. MDA cells showed 27% more incorporation of BrdU than reflected by S-phase determination with flow cytometric DNA content analysis, whereas these values were found to be of the same size in both HTB-125 and MCF-7 cells.
Conclusions
Our data indicate that the breast cancer cell lines MCF-7 and MDA-231, although both DNA-aneuploid, differ significantly regarding the degree of cell cycle disturbance and centrosome aberrations, which partly could explain the different genomic stability of the two cell lines. The results also question the reliability of cytometric DNA content based S-phase determination in genomically unstable tumor cell populations.
Two BODIPY derivative sensors for metal ion recognition containing 10-(4-hydroxyphenyl) (L1) and 10-(3,4-dihydroxyphenyl) (L2) were synthesized in a one-pot reaction of benzaldehyde derivative and 2,4-dimethylpyrrole in the presence of trifluoroacetic acid as catalyst. The binding abilities between these sensors and 50 equivalents of Na+, K+, Ag+, Ca2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Pb2+, Al3+ and Cr3+ ions were studied using UV–vis and fluorescent spectroscopic methods. Of all the metal ions tested, Al3+ ion showed the greatest decrease in intensity in the spectra of the sensors, and therefore Al3+ ion forms the strongest complex. The binding abilities of BODIPY receptors with Na+, Ag+, Ca2+, Co2+, Ni2+, Cu2+, Zn2+ and Al3+ ions were also investigated using density functional theory (DFT) calculations at B3LYP/LanL2DZ theoretical level. The calculated results point to the same conclusion. DFT calculations also provided the HOMO–LUMO energy levels, which can explain the spectrum change upon complexation.
Figure
Graphical structure, fluorescent spectra, frontier orbital energy diagrams and electron-transfer paths in sensor L1, and after attachment with Al3+ ion. 相似文献
Programmed cell death (PCD) or apoptosis is a process whereby developmental or environmental stimuli activate a specific series
of events that culminate in cell death. PCD is essential for normal development and abnormality in the process can lead to
defects ranging from embryonic lethality and tissue-specific perturbation of postnatal development to a high susceptibility
to malignancy. Therapeutics that modulate the regulation of PCD may provide a new opportunity for the treatment of the PCD
related diseases and cancer. CD40 and CD95 (Fas/Apo-I) are transmembrane proteins of the nerve growth factor/tumour necrosis
factor α receptor superfamily. The death signal of PCD occurs when the CD95 receptor on the cell surface binds to the CD95
ligand (CD95L) or to the anti-CD95 monoclonal antibody (mAb). In contrast, PCD could be inhibited by the survival signal mediated
from the binding of the CD40 receptor to the CD40 ligand (CD40L) or to the anti-CD40 mAb. In this review, the interaction
of CD40/CD40L and CD95/CD95L on PCD in normal and malignant cells is discussed. 相似文献