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51.
Aberrant expression of microRNAs (miRNAs) is involved in the development and progression of various types of cancers. In this study, we investigated the role of miR-331-3p in cell proliferation and the expression of keratinocyte differentiation markers of uterine cervical cancer cells. Moreover, we evaluated whether neuropilin 2 (NRP2) are putative target molecules that regulate the human papillomavirus (HPV) related oncoproteins E6 and E7. Cell proliferation in the human cervical cancer cell lines SKG-II, HCS-2, and HeLa was assessed using the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay. Cellular apoptosis was measured using the TdT-mediated dUTP nick end labeling (TUNEL) and Annexin V assays. Quantitative RT-PCR was used to measure the messenger RNA (mRNA) expression of the NRP2, E6, E7, p63, and involucrin (IVL) genes. A functional assay for cell growth was performed using cell cycle analyses. Overexpression of miR-331-3p inhibited cell proliferation, and induced G2/M phase arrest and apoptosis in SKG-II, HCS-2 and HeLa cells. The luciferase reporter assay of the NRP2 3′-untranslated region revealed the direct regulation of NRP2 by miR-331-3p. Gene expression analyses using quantitative RT-PCR in SKG-II, HCS-2, and HeLa cells overexpressing miR-331-3p or suppressing NRP2 revealed down-regulation of E6, E7, and p63 mRNA and up-regulation of IVL mRNA. Moreover, miR-331-3p overexpression was suppressed NRP2 expression in protein level. We showed that miR-331-3p and NRP2 were key effectors of cell proliferation by regulating the cell cycle, apoptosis. NRP-2 also regulates the expression of E6/E7 and keratinocyte differentiation markers. Our findings suggest that miR-331-3p has an important role in regulating cervical cancer cell proliferation, and that miR-331-3p may contribute to keratinocyte differentiation through NRP2 suppression. miR-331-3p and NRP2 may contribute to anti-cancer effects.  相似文献   
52.
This work examines the polycondensation of 4-chloropyridine derivatives using an N-(4-tert-butylbenzyl)-4-chloropyridinium (BPymCl) initiator and ion exchange reagents NaBPh4, NaBF4, and TBABF4. The 1H NMR spectra demonstrate that the product quantity is proportional to the total conversion of the monomer and the initiator. The MALDI-TOF MS spectrum shows that the product contains more than 9 monomer units. The polymerization was well-terminated via the addition of dimethylaminopyridine. These results indicate that the polycondensation proceeds in a chain-growth manner. This polycondensation could be a new example of a controlled polymerization with a well-defined end group.  相似文献   
53.
Cortisol-producing adenoma (CPA) is composed of clear and compact cells. Clear cells are lipid abundant, and compact ones lipid poor but associated with higher production of steroid hormones. PRKACA mutation (PRKACA mt) in CPA patients was reported to be associated with more pronounced clinical manifestation of Cushing’s syndrome. In this study, we examined the association of histological features and genotypes with cholesterol uptake receptors and synthetic enzymes in 40 CPA cases, and with the quantitative results obtained by gas chromatography-mass spectrometry (GC-MS) analysis in 33 cases to explore their biological and clinical significance. Both cholesterol uptake receptors and synthetic enzymes were more abundant in compact cells. GC-MS analysis demonstrated that the percentage of compact cells was inversely correlated with the concentrations of cholesterol and cholesterol esters, and positively with the activity of cholesterol biosynthesis from cholesterol esters. In addition, hormone-sensitive lipase (HSL), which catalyzes cholesterol biosynthesis from cholesterol esters, tended to be more abundant in compact cells of PRKACA mt CPAs. These results demonstrated that both cholesterol uptake and biosynthesis were more pronounced in compact cells in CPA. In addition, more pronounced HSL expression in compact cells of PRKACA mt CPA could contribute to their more pronounced clinical manifestation.  相似文献   
54.
Radical scavenger, radical anion scavenger, and peroxide decomposer were added to aromatic hydrocarbons and phosphates in aromatic rings with and without side chain, and the effect of these inhibitors on tribopolymerisation and the lubrication characteristics of the aromatic compounds were investigated, in various atmospheres, in order to clarify the reaction mechanism. The aromatics of both hydrocarbons and phosphates with a methyl group in aromatic rings react readily at the rubbing surfaces to form polymer or polymer-like products, improving the lubricating characteristics. The tribochemical reactions of alkylaromatic compounds is shown to differ from those of trialkyl or triarylphosphates. It was concluded that the reaction proceeds through the radical or radicalanion and via peroxide to cause polymerisation.  相似文献   
55.
To find an effective laser source to ignite energetic materials, the absorption spectra of some energetic materials are obtained by means of a photoacoustic spectroscopy (PAS). In this experiment, PAS covers the wavelength region of 400 nm-1600 nm in which no other conventional method can take absorption spectra for powdered energetic materials. Photoacoustic spectra of 18 energetic materials are reported. In general, energetic materials tested showed peaks in 600 nm–800 nm and 1400 nm–1600 nm ranges. It is found that the energy required to initiate explosives in the case of ruby laser initiation were correlated with their photoacoustic signal intensities.  相似文献   
56.
The extraction of oil from fungi (Mortierella ramanniana var.angulispora) was studied using carbon dioxide (CO2), nitrous oxide (N2O), trifluoromethane (CHF3) and sulfur hexafluoride (SF6) under supercritical conditions. The oil solubility was highest in SC-N2O followed by SC-CO2, while both SC-CHF3 and SC-SF6 showed poorer solvent power. The recorded oil solubilities at 333 K and 24.5 MPa were 2.3 wt% in N2O, 0.48 wt% in CO2, 0.0099 wt% in CHF3 and 0.0012 wt% in SF6. The oil solubilities in SC-N2O and SC-CO2 were measured over the pressure range 15.7–29.4 MPa and at temperatures ranging from 313–353 K. N2O always showed greater solvent power than did CO2 at the same temperature and pressure. The solvent power of a supercritical fluid increases with density at a given temperature, and increases with temperature at constant density. The change in neutral lipid composition of the extracted oil with the extraction ratio was measured. Free fatty acids or diglycerides were extracted more easily than triglycerides or sterol esters. The change in fatty acid composition was also measured. The proportion of γ-linolenic acid in the extract remained constant throughout the extraction.  相似文献   
57.
以连接端子、印刷电路板和电镀通孔3种不同材料构成的一种可拔插截面针型汽车电子连接器为研究对象,为满足其在非塑性状态下相互接触实现可反复拔插、稳定低电阻的连接要求。针对连接可靠性设计问题,利用接触动力学理论,对基于设计参数变化的连接器米赛斯应力和接触应力分布进行了解析和灵敏度分析,得到了影响其连接性能的关键设计参数。文中为减少高精度设计参数灵敏度解析的计算时间,提出了将连接端子前、后段形态设计参数分离的解析法,即在接触力学解析过程中,首先以准静态接触方法对连接端子后段(连接形态)设计参数进行接触力学解析,再以动态接触方法对连接端子前段(插拔形态)设计参数进行接触力学解析的方法。其结果对同类微小型可拔插截面针型汽车电子连接器设计参数的确定具有参考价值。  相似文献   
58.
The n-6/n-3 fatty acid (FA) ratio has increased in the Western-style diet to ~10–15:1 during the last century, which may have contributed to the rise in cardiovascular disease (CVD). Prior studies have evaluated the effects on CVD risk factors of manipulating the levels of n-6 and n-3 FA using food and supplements or investigated the metabolic fate of linoleic acid (LNA) and α-linolenic acid (ALA) by varying the n-6/n-3 ratios. However, no previous studies have investigated the potential interaction between diet ratios and supplementation with eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3). We used a factorial design approach with adults (n = 24) in a controlled feeding trial to compare the accretion of EPA and DHA into red blood cell membranes (RBC) by adding a direct source (algal oil supplement) of EPA and DHA in a diet with a 10:1 versus 2:1 ratio of n-6/n-3 FA. Subjects were randomized into 8-week crossover diet sequences and each subject consumed three of four diets [10:1, 10:1 plus supplement (10:1 + S), 2:1 and 2:1 + S]. LNA and ALA intakes were 9.4 and 7.7%, and 1.0 and 3.0% during the low and high ALA diets, respectively. Compared to the Western-style 10:1 diet, the 2:1 diet increased EPA by 60% (P < 0.0001) in RBC membranes without the direct EPA source and a 34% increase (P = 0.027) was observed with the 10:1 + S diet; however, DHA levels increased in both diet ratios only with a direct DHA source. Shifting towards a 2:1 diet is a valid alternative to taking EPA-containing supplements.  相似文献   
59.
Anthropogenic activities have exerted increasingly large-scale influences on terrestrial ecological systems from the past century, primarily through agriculture; however, the impact of such changes on the hydrologic cycle is poorly understood. As one of the important land use (LU) in the coastal Dogo Plain of the Seto Inland Sea, Japan, paddy fields have been decreasing with the increase in urbanization in recent decades. As the main source of water in the Dogo Plain, groundwater plays an important role in providing people with fresh water and contributing to stream base flow. The purpose of this study is to analyze the water resource and evaluate the effect of LU change on groundwater table fluctuation in this coastal plain. Firstly, the observations of groundwater table and the investigation of water balance were carried out in this alluvial plain. Then, a distributed four-block three-layer water balance model was employed to analyze the groundwater table fluctuation with response to the change of paddy field area. Moreover, the role of paddy field in recharging groundwater in the basin has been clarified. Results show that groundwater table depends not only on rainfall and discharge from rivers, but also on irrigation water and topology of the study area. The net groundwater recharge was positive in irrigation periods whereas that in non-irrigation periods was nearly equal to zero or negative. The results of this study would be helpful to the urban development policy and land use planning decision.  相似文献   
60.
The drying characteristics of porous material in fluidized bed were examined theoretically and experimentally. The brick ball was used as the sample and immersed in the fluidized bed. The glass beads were used as the fluidizing particles and the particle diameters were changed. When the pore diameter of sample was relatively large, the fluidizing particles were adhered on the sample surface. In the theoretical analysis, the heat and mass transfers in adhered particle layer were considered. The fluidizing particles were adhered on the sample surface during the earlier period of drying. The sample temperature largely decreased when the mass of adhered particle decreased. The calculated results are in good agreement with experimental data. The diameter of fluidizing particle had a small effect on the drying time. The excess increments in drying gas temperature hardly contributed to shortening the drying time.  相似文献   
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