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排序方式: 共有435条查询结果,搜索用时 15 毫秒
91.
92.
Giedr Valiulien Aida Vitkevi
ien Giedr Skliut Veronika Borutinskait Rta Navakauskien 《Molecules (Basel, Switzerland)》2021,26(8)
Metabolic landscape and sensitivity to apoptosis induction play a crucial role in acute myeloid leukemia (AML) resistance. Therefore, we investigated the effect of metformin, a medication that also acts as an inhibitor of oxidative phosphorylation (OXPHOS), and MCL-1 inhibitor in AML cell lines NB4, KG1 and chemoresistant KG1A cells. The impact of compounds was evaluated using fluorescence-based metabolic flux analysis, assessment of mitochondrial Δψ and cellular ROS, trypan blue exclusion, Annexin V-PI and XTT tests for cell death and cytotoxicity estimations, also RT-qPCR and Western blot for gene and protein expression. Treatment with metformin resulted in significant downregulation of OXPHOS; however, increase in glycolysis was observed in NB4 and KG1A cells. In contrast, treatment with S63845 slightly increased the rate of OXPHOS in KG1 and KG1A cells, although it profoundly diminished the rate of glycolysis. Generally, combined treatment had stronger inhibitory effects on cellular metabolism and ATP levels. Furthermore, results revealed that treatment with metformin, S63845 and their combinations induced apoptosis in AML cells. In addition, level of apoptotic cell death correlated with cellular ROS induction, as well as with downregulation of tumor suppressor protein MYC. In summary, we show that modulation of redox-stress could have a potential anticancer activity in AML cells. S63845相似文献
93.
With biologically important "peptide bundling" as the motif, new chromophoric cyclic host 1 was designed, which consists of two zinc porphyrin units that are connected by dynamic peptide helices of nonameric aminoisobutyric acid (Aib) units. Upon inclusion of pyridine-anchored helical peptides between the zinc porphyrin units, 1 displayed an intense exciton-coupled circular dichroism (CD) band at 410-450 nm, whose sign reflected the helical sense of the guest peptides. Studies with conformationally defined dehydrophenylalanine-containing analogues indicated that the dynamic helical chains in the host are stereochemically harmonized with right- or left-handed helices of the guest peptides in a confined nano space, leading to either clockwise- or anticlockwise-twisted geometry (chiroptical output) of the connecting zinc porphyrin chromophores. 相似文献
94.
Petra Klinzing Aida El-Kholi Ulrich Müller K. Dehnicke Kurt Findeisen 《无机化学与普通化学杂志》1989,569(1):83-90
Reactions of N-Chloroacetoneimine with Molybdenum Pentachloride and Tungsten Hexachloride. Crystal Structure of Me2C?NH2[MoOCl4] WCl6 reacts with N-chloroacetoneimine under elimination of chlorine and formation of pentachloro-isopropylideneimino-tungsten(VI), Cl5W?N?CMe2, a brown-black crystal powder, which was characterized by i.r. spectroscopy. MoCl5 reacts in a similar way, although only a product mixture can be obtained. Partial hydrolysis of this mixture yields isopropylideneiminium-tetrachlorooxomolybdate(V), Me2C?NH2+[MoOCl4]?, of which the crystal structure was determined (2323 unique observed reflexions, R = 0.049). Space group P21/c, Z = 4, a = 878.6, b = 907.2, c = 1252.2 pm, β = 91.29°. The compound consists of Me2C?NH2+ ions with a planar arrangement of the skeletal atoms and a CN bond length of 126.7 pm and of dimeric, centrosymmetric anions [MoOCl4]22? having Mo atoms linked via asymmetric chloro bridges (MoCl distances 238.4 and 307.6 pm). The longer Mo? Cl contacts are located in the trans-positions of the terminal oxoligands (MoO distance 164 pm). 相似文献
95.
An amphiphilic zinc porphyrin-fullerene dyad appended with triethyleneglycol chains in aqueous media forms uniformly-sized multilamellar vesicles with a mean diameter of 100 nm that are thermally stable and robust against membrane lysis with surfactants. 相似文献
96.
Incorporation of imidazolium ion functionalities into the paraffinic side-chain termini of a triphenylene derivative resulted in stabilization of a columnar mesophase of its liquid crystalline assembly, which was retained over a wider temperature range down to 4 degrees C by an externally added imidazolium-based ionic liquid. 相似文献
97.
Aida Serra Laura Rubió Alba Macià Rosa-M Valls Úrsula Catalán Rafael de la Torre Maria-José Motilva 《Analytical and bioanalytical chemistry》2013,405(28):9179-9192
Two different rapid sample pretreatment strategies, dried spot cards, and microelution solid-phase extraction plates (μSPE), with ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) have been developed and validated for the determination of hydroxytyrosol and its metabolites in spiked human urine samples. Hydroxytyrosol, hydroxytyrosol-3′-O-glucuronide, hydroxytyrosol-4′-O-glucuronide, hydroxytyrosol-3-O-sulphate, and homovanillic alcohol-4′-O-glucuronide were used as the target compounds. Using the FTA DMPK-A dried urine spot card under optimum conditions, with 5 μL of preconcentrated urine volume and 100 μL of methanol/water (50/50, v/v) as the elution solvent, the extraction recovery (%R) of the compounds studied was higher than 80 %, and the matrix effect (%ME) was less than 8 %. The stability of these cards and punching at the centre or side of the card were also studied, obtaining an excellent stability after 7 days of storage and complete homogeneity across the surface of the dried drop. The different μSPE parameters that affect the efficiency were also studied, and under optimum conditions, the %R and the %ME were higher than 70 % and lower than 17 %, respectively. The linearity range in dried urine spot cards was 2.5-20 μM for all the metabolites, with the exception of hydroxytyrosol-3-O-sulphate and hydroxytyrosol, which were 0.3-70 μM and 2.5-50 μM respectively. With regards to μSPE, the linearity range was 0.5-5 μM for all the studied compounds, except for hydroxytyrosol-3-O-sulphate, which was 0.08-5 μM. The quantification limits (LOQs) were 0.3-2.5 μM and 0.08-0.5 μM in dried spot cards and in μSPE, respectively. The two developed methods were then applied and compared for determining hydroxytyrosol and its metabolites in human 24 h-urine samples after a sustained consumption (21 days) of a phenol-enriched virgin olive oil. The metabolites identified were hydroxytyrosol in its glucuronide and sulphate forms, homovanillic alcohol in its glucuronide and sulphate forms, homovanillic acid sulphate and hydroxytyrosol acetate sulphate. 相似文献
98.
In complex domains it is usually quite difficult to introduce context information. However, sometimes that information should be taken into account to make decisions, because it provides some relevant knowledge that cannot be expressed using an attribute-value representation. This is the case of the determination of risk of contamination of soils. In this paper, we propose to use conjunctive rules to introduce additional background knowledge to a MCDM sorting method called ClusDM. ClusDM is based on the aggregation of the data with unsupervised clustering techniques. The paper presents a new algorithm to incorporate rules to guide the clustering process in a semi-supervised way. The paper also describes how it works in the case sorting a set of possible contaminated soils, and compares the results obtained by ClusDM when rules are used or not. 相似文献
99.
100.