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101.
The inhibitory potency of the series of inhibitors of the soluble epoxide hydrolase (sEH) based on the selenourea moiety and containing adamantane and aromatic lipophilic groups ranges from 34.3 nM to 1.2 μM. The most active compound 5d possesses aliphatic spacers between the selenourea group and lipophilic fragments. Synthesized compounds were tested against the LPS-induced activation of primary murine macrophages. The most prominent anti-inflammatory activity, defined as a suppression of nitric oxide synthesis by LPS-stimulated macrophages, was demonstrated for compounds 4a and 5b. The cytotoxicity of the obtained substances was studied using human neuroblastoma and fibroblast cell cultures. Using these cell assays, the cytotoxic concentration for 4a was 4.7–18.4 times higher than the effective anti-inflammatory concentration. The genotoxicity and the ability to induce oxidative stress was studied using bacterial lux-biosensors. Substance 4a does not exhibit genotoxic properties, but it can cause oxidative stress at concentrations above 50 µM. Put together, the data showed the efficacy and safety of compound 4a.  相似文献   
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西西伯利亚盆地上侏罗统-下白垩统巴热诺夫组硅质-钙质富有机质泥页岩总有机碳(TOC)含量高且有机质成熟度适中,是俄罗斯目前页岩油的勘探首选目的层系。近年研究表明,该套富有机质页岩层段发育数套厘米-毫米级的火山灰夹层,具黄色荧光,岩心薄片见大量沸石等火山灰蚀变矿物,使该区火山灰与富有机质形成的相互关系引起关注。以该盆地的巴热诺夫组为例,介绍了火山灰对该区富有机质页岩形成的影响。巴热诺夫组的地质-地球化学分析表明,在火山灰发育同期沉积的富有机质层段中不仅硅、磷等营养元素含量高,而且钡、锰、钼、铀等藻类繁殖催化元素含量也高,推测火山灰携带物质促进了巴热诺夫页岩沉积时期古生物的大量繁殖甚至爆发,为富有机质的形成奠定了物质基础;同时,在火山灰发育层段之上的富有机质泥页岩中大量发育草莓状黄铁矿,且呈层状分布,Co/Ni比值小于1,S/Fe比值偏高,指示火山灰喷发之后形成缺氧的强还原环境,有利于泥页岩中有机质的保存;火山灰发育井区TOC含量高(多>7%),有机质成熟度与邻近火山灰不发育区相比偏高(Ro=0.7%~1.1%),生烃潜力高且已达到生油高峰,推测可能火山灰携带的...  相似文献   
104.
Stemness and epithelial–mesenchymal plasticity are widely studied in the circulating tumor cells of breast cancer patients because the roles of both processes in tumor progression are well established. An important property that should be taken into account is the ability of CTCs to disseminate, particularly the viability and apoptotic states of circulating tumor cells (CTCs). Recent data demonstrate that apoptosis reversal promotes the formation of stem-like tumor cells with pronounced potential for dissemination. Our study focused on the association between different apoptotic states of CTCs with short- and long-term treatment outcomes. We evaluated the association of viable CTCs, CTCs with early features of apoptosis, and end-stage apoptosis/necrosis CTCs with clinicopathological parameters of breast cancer patients. We found that the proportion of circulating tumor cells with features of early apoptosis is a perspective prognosticator of metastasis-free survival, which also correlates with the neoadjuvant chemotherapy response in breast cancer patients. Moreover, we establish that apoptotic CTCs are associated with the poor response to neoadjuvant chemotherapy, and metastasis-free survival expressed at least two stemness markers, CD44 and CD133.  相似文献   
105.
铝合金钻杆因具有质量轻、比强度高、抗腐蚀性好、低磁等优点,在深井与超深井钻探作业中备受关注.在深井与超深井钻进中,铝合金钻杆需要承受巨大的内外压力,因此有必要对钻杆所能承受的最大内外压力进行计算与试验,对自行研制的Ø147 mm铝合金钻杆进行了静水内、外压试验与弹性力学理论计算校核,7075铝合金钻杆在内压69.51 MPa时持续加压20 min,没有发生泄漏现象;最大抗外压值为107.4 MPa.2024铝合金钻杆在内压48.65 MPa时持续加压20 min,没有发生泄漏现象;最大抗外压值为72.3 MPa.试验表明,铝合金钻杆抗内、外压性能良好,从而保证了铝合金钻杆在深井及超深井钻进时的可靠性.  相似文献   
106.
Mollusks are unique animals with a relatively simple central nervous system (CNS) containing giant neurons with identified functions. With such simple CNS, mollusks yet display sufficiently complex behavior, thus ideal for various studies of behavioral processes, including long-term memory (LTM) formation. For our research, we use the formation of the fear avoidance reflex in the terrestrial mollusk Helix lucorum as a learning model. We have shown previously that LTM formation in Helix requires epigenetic modifications of histones leading to both activation and inactivation of the specific genes. It is known that microRNAs (miRNAs) negatively regulate the expression of genes; however, the role of miRNAs in behavioral regulation has been poorly investigated. Currently, there is no miRNAs sequencing data being published on Helix lucorum, which makes it impossible to investigate the role of miRNAs in the memory formation of this mollusk. In this study, we have performed sequencing and comparative bioinformatics analysis of the miRNAs from the CNS of Helix lucorum. We have identified 95 different microRNAs, including microRNAs belonging to the MIR-9, MIR-10, MIR-22, MIR-124, MIR-137, and MIR-153 families, known to be involved in various CNS processes of vertebrates and other species, particularly, in the fear behavior and LTM. We have shown that in the CNS of Helix lucorum MIR-10 family (26 miRNAs) is the most representative one, including Hlu-Mir-10-S5-5p and Hlu-Mir-10-S9-5p as top hits. Moreover, we have shown the involvement of the MIR-10 family in LTM formation in Helix. The expression of 17 representatives of MIR-10 differentially changes during different periods of LTM consolidation in the CNS of Helix. In addition, using comparative analysis of microRNA expression upon learning in normal snails and snails with deficient learning abilities with dysfunction of the serotonergic system, we identified a number of microRNAs from several families, including MIR-10, which expression changes only in normal animals. The obtained data can be used for further fundamental and applied behavioral research.  相似文献   
107.
Scientists have long established that fatty acids are the primary substrates for kidney mitochondria. However, to date we still do not know how long-chain and middle-chain fatty acids are oxidized at the mitochondrial level. Our previous research has shown that mitochondria from the heart, brain, and kidney oxidize palmitoylcarnitine at a high rate only in the presence of succinate, glutamate, or pyruvate. In this paper, we report properties of the isolated kidney mitochondria and how malate and succinate affect the oxidation of C16 and C8 acylcarnitines. The isolated kidney mitochondria contain very few endogenous substrates and require malate to oxidize pyruvate, glutamate, and C16 or C8 acylcarnitines. We discovered that with 10 µM of C16 or C8 acylcarnitines, low concentrations of malate (0.2 mM) or succinate (0.5 mM) enhance the States 4 and 3 respiratory rates several times. The highest respiration rates were observed with C16 or C8 acylcarnitines and 5 mM succinate mixtures. Results show that kidney mitochondria, unlike the heart and brain mitochondria, lack the intrinsic inhibition of succinate dehydrogenase. Additionally, results show that the oxidation of fatty acid by the small respirasome’s supercomplex generates a high level of CoQH2, and this makes SDH in the presence of succinate reverse the flow of electrons from CoQH2 to reduce fumarate to succinate. Finally, we report evidence that succinate dehydrogenase is a key mitochondrial enzyme that allows fast oxidation of fatty acids and turns the TCA cycle function from the catabolic to the anabolic and anaplerotic metabolic pathways.  相似文献   
108.
Nanoparticles are heterologous small composites that are usually between 1 and 100 nanometers in size. They are applied in many areas of medicine with one of them being drug delivery. Nanoparticles have a number of advantages as drug carriers which include reduced toxic effects, increased bioavailability, and their ability to be modified for specific tissues or cells. Due to the exciting development of nanotechnology concomitant with advances in biotechnology and medicine, the number of clinical trials devoted to nanoparticles for drug delivery is growing rapidly. Some nanoparticles, lipid-based types, in particular, played a crucial role in the developing and manufacturing of the two COVID-19 vaccines—Pfizer and Moderna—that are now being widely used. In this analysis, we provide a quantitative survey of clinical trials using nanoparticles during the period from 2002 to 2021 as well as the recent FDA-approved drugs (since 2016). A total of 486 clinical trials were identified using the clinicaltrials.gov database. The prevailing types of nanoparticles were liposomes (44%) and protein-based formulations (26%) during this period. The most commonly investigated content of the nanoparticles were paclitaxel (23%), metals (11%), doxorubicin (9%), bupivacaine and various vaccines (both were 8%). Among the FDA-approved nanoparticle drugs, polymeric (29%), liposomal (22%) and lipid-based (21%) drugs were the most common. In this analysis, we also discuss the differential development of the diverse groups of nanoparticles and their content, as well as the underlying factors behind the trends.  相似文献   
109.
110.
Scope: Autophagy (type II programmed cell death) is crucial for maintaining cellular homeostasis. Several autophagy‐deficient or knockout studies indicate that autophagy is a tumor suppressor. Tetrahydrocurcumin (THC), a major metabolite of curcumin, has been demonstrated with anti‐colon carcinogenesis and antioxidation in vivo. Methods and results: In the present study, we found that treatment with THC induced autophagic cell death in human HL‐60 promyelocytic leukemia cells by increasing autophage marker acidic vascular organelle (AVO) formation. Flow cytometry also confirmed that THC treatment did not increase sub‐G1 cell population whereas curcumin did with strong apoptosis‐inducing activity. At the molecular levels, the results from Western blot analysis showed that THC significantly down‐regulated phosphatidylinositol 3‐kinase/protein kinase B and mitogen‐activated protein kinase signalings including decreasing the phosphorylation of mammalian target of rapamycin, glycogen synthase kinase 3β and p70 ribosomal protein S6 kinase. Further molecular analysis exhibited that the pretreatment of 3‐methyladenine (an autophagy inhibitor) also significantly reduced acidic vascular organelle production in THC‐treated cells. Conclusion: Taken together, these results demonstrated the anticancer efficacy of THC by inducing autophagy as well as provided a potential application for the prevention of human leukemia.  相似文献   
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