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991.
Yiwen Liu Jianfang Gao Min Xu Qianqian Zhou Zhongxiao Zhang Jiaxin Ye Rui Li 《Journal of cellular and molecular medicine》2022,26(13):3616
Congenital heart disease (CHD) is the most common birth defect, affecting approximately 1% of live births. Genetic and environmental factors are leading factors to CHD, but the mechanism of CHD pathogenesis remains unclear. Circular RNAs (circRNAs) are kinds of endogenous non‐coding RNAs (ncRNAs) involved in a variety of physiological and pathological processes, especially in heart diseases. In this study, three significant differently expressed circRNA between maternal embryonic day (E) E13 and E17 was found by microarray assay. Among them, the content of circ‐RCCD increases with the development of heart and was enriched in primary cardiomyocytes of different species, which arouses our attention. Functional experiments revealed that inhibition of circ‐RCCD dramatically suppressed the formation of beating cell clusters, the fluorescence intensity of cardiac differentiation marker MF20, and the expression of the myocardial‐specific markers CTnT, Mef2c, and GATA4. Next, we found that circ‐RCCD was involved in cardiomyocyte differentiation through negative regulation of MyD88 expression. Further experiments proved that circ‐RCCD inhibited MyD88 levels by recruiting YY1 to the promoter of MyD88; circ‐RCCD inhibited nuclear translocation of YY1. These results reported that circ‐RCCD promoted cardiomyocyte differentiation by recruiting YY1 to the promoter of MyD88. And, this study provided a potential role and molecular mechanism of circ‐RCCD as a target for the treatment of CHD. 相似文献
992.
【目的】水产养殖过程中蜡状芽孢杆菌(Bacillus cereus)作为益生菌被广泛应用。本研究旨在深入了解分离于养殖水体中的一株蜡状芽孢杆菌S458-1对养殖水体以及养殖对象的影响,以期为菌株S458-1在水产养殖生产上的应用提供理论依据。【方法】根据控制变量法,各试验组鲫鱼养殖模式设置相同温度、盐度、溶氧和pH,利用分光光度法测定水体的水化学指标;利用试剂盒法测定鲫鱼的血清生理生化指标。【结果】添加菌株S458-1处理组(终浓度分别为10~6、10~7、10~8CFU/mL)与对照组(未加S458-1菌)相比:水体活性磷浓度显著性增加(P0.05);同时具有把NH_4~+-N和NO_2~–-N转化为NO_3~–-N的趋势,但无显著性差异(P0.05);养殖鲫鱼血清检测结果显示谷草转氨酶(GOT)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)以及丙二醛(MDA)含量均显著降低(P0.05)。【结论】蜡状芽孢杆菌S458-1具有脱氮解磷、调节水质的作用,并可增强养殖对象的生理健康状态,可作为益生菌应用于水产养殖中,具有较高的应用价值。 相似文献
993.
Sei-Woong Choi 《Ecological Research》2016,31(3):321-331
We investigated elevational richness patterns of three moth groups (Erebidae, Geometridae, and Noctuidae) along four elevational gradients located on one northern and three southern mountains in South Korea, as well as the effects of plants and climatic factors on the diversity patterns of moths. Moths were collected with an ultraviolet light trap at 32 sites from May through October, 2013. Plant species richness and mean temperatures for January and June were acquired. Observed and estimated moth species richness was calculated and the diversity patterns with null models were compared. Species richness along four elevational gradients peaked at mid-elevations, whereas deviations occurred at elevations below mid-peak in the southern mountains and elevations higher than mid-peak on the northern mountain. Species richness curves of three moth groups also peaked at mid-elevations throughout South Korea. However, the species richness curves for Erebidae were positively skewed, indicating that a preference for lowlands, whereas curves of the Geometridae were negatively skewed, indicating a preference for highlands. The mid-peak diversity pattern between plants and moths on the Korean mountains showed an elevational breadth that overlapped between 800 and 900 m. Multiple regression analysis revealed that plant species richness and January mean temperature significantly influenced moth species richness and abundance. The rapid increase in mean annual temperature in the Korean peninsula and the unimodal elevational gradients of moths across the country suggest that an uphill shift in peak optimum elevation and changes in the highest peak of the curve will occur in the future. 相似文献
994.
To investigate the effect of human pyruvate carboxylase (hPC) on lactate formation in Chinese hamster ovary (CHO) cell lines,
FLAG-tagged hPC was introduced into a dihydrofolate-deficient CHO cell line (DG44). Three clones expressing high levels of
hPC, determined by Western blotting using an anti-FLAG monoclonal antibody, and a control cell line were established. Immunocytochemistry
revealed that a substantial amount of expressed hPC protein was localized in the mitochondria of the cells. hPC expression
did not impair cell proliferation. Rather, it improved cell viability at the end of adherent batch cultures with the serum-containing
medium probably because of reduced lactate formation. Compared with control cells, specific lactate production rate of the
three clones was decreased by 21–39%, which was because of a decreased specific glucose uptake rate and yield of lactate from
glucose. Reduced lactate formation by hPC expression was also observed in suspension fed-batch cultures using a serum-free
medium. Taken together, these results demonstrate that through the expression of the hPC enzyme, lactate formation in CHO
cell culture can be efficiently reduced. 相似文献
995.
Patricia Fagundes Costa Geisa Ferreira Fernandes Priscila Oliveira dos Santos Cristiane Candida Amaral Zoilo Pires Camargo 《Mycopathologia》2010,169(1):37-46
The ecological niche or exact habitat of the fungus Paracoccidioides brasiliensis is not known, and few isolates have been obtained from the environment. In this study, ten isolates were analyzed with respect
to antigenic composition, serology, pathogenicity, and molecular aspects. Gp43 is considered to be the molecular basis for
the serodiagnosis of paracoccidioidomycosis; however, in this study only six of the environmental isolates secreted this molecule
(four in great amounts and two in small amounts). Other molecules were also produced. When exoantigens from these isolates
were tested using immunodiffusion, only four preparations were positive by ID tests. However, when these exoantigens were
tested by ELISA, all of them except one were able to detect anti-P. brasiliensis antibodies. In Western blot assays, these exoantigens showed different reactivities. Isolates that secreted gp43 presented
positive reactions for this molecule, and isolates that did not secrete gp43 gave positive reactions for other minor molecules.
RAPD analysis revealed that there is great genetic variation between these environmental isolates. These isolates were non-pathogenic:
no mortality was observed among the inoculated mice during an 18-month follow-up period. 相似文献
996.
Quercetin and other flavonoids have been reported to exhibit both antioxidant and pro‐oxidant properties. Most studies about the pro‐oxidative ability were conducted in the presence of metal ions, and the essential functional moiety of quercetin responsible for the pro‐oxidative effect is still unclear. In this study, we evaluated the pro‐oxidative abilities in the absence of metal ions of two quercetin derivatives, i.e., quercetin‐3′‐O‐β‐D ‐glucoside ( 1 ) and quercetin‐3‐O‐β‐D ‐glucoside ( 2 ), by assessing DNA cleavage and HO.‐radical production. The binding mode between these compounds and DNA was studied by fluorescence and viscometric titrations. The results showed that 1 can efficiently induce oxidative damage to plasmid DNA, while 2 shows poor activity. Both 1 and 2 bind to DNA via groove‐binding. These results proved that the α‐hydroxy‐β‐oxo‐α,β‐enone moiety contributes to the pro‐oxidative activity of quercetin. 相似文献
997.
Magdalena Semla Pavol Schwarcz Ján Mezey Łukasz J. Binkowski Martyna Błaszczyk Grzegorz Formicki Agnieszka Greń Robert Stawarz Peter Massanyi 《Biological trace element research》2018,184(1):33-41
Wine consumption delivers macroelements and microelements necessary for the proper metabolism. On the other hand, wine can be an important source of toxic metals. The aim of this study was to estimate the concentrations of Ca, Cd, Cu, Fe, Hg, Mg, Ni, Pb, and Zn in the Slovak and non-Slovak wines. The concentration of metals was evaluated with respect to the type, the alcohol content, and the age of Slovak wine. The general scheme of concentrations found was as follows Ca > Mg > Fe > Zn > Pb > Cd > Ni > Cu > Hg. The type of wine and the alcohol content do not have a significant impact on metal concentrations. Also, the age of wine has no influence on the mean concentration of metals, except for Zn. Metal concentrations in Slovak and non-Slovak wines indicate similar contents of metals, except for Ni. The contribution to both dietary reference values (DRVs) and provisional tolerable weekly intake (PTWI) evaluations in the Slovak wine suggested low dietary exposure to Ca, Cu, Fe, Mg, Ni, Zn, Cd, Hg, and Pb, respectively. However, we do not suggest that the consumption of all Slovak wines is healthy. The maximum Pb concentrations in Slovak wines exceed the maximum permitted level proposed by the European Commission. This might be proved by the results of the margin of the exposure (MOE) value evaluation in the samples containing the maximum Pb concentrations, showing a high risk of CKD and SBP in high and extreme consumption groups. 相似文献
998.
目的 探讨结核杆菌感染与恶性肿瘤的关系。方法 采用多聚酶链反应(PCR) 技术检测两种恶性肿瘤组织中结核杆菌DNA(TB- DNA) 。结果41 例恶性肿瘤组织中检出TB- DNA 阳性患者8 例,占19.5 % ,且TB-DNA 阳性患者肿瘤发病部位基本与结核病的好发部位一致。结论 结核杆菌感染可能与一些恶性肿瘤存在特殊相关性。 相似文献
999.
Due to their unique fluorescent properties, quantum dots present a great potential for biolabelling applications; however,
the toxic interactions of quantum dots with biopolymers are little known. The toxic interactions of glutathione-capped CdTe
quantum dots with trypsin were studied in this paper using synchronous fluorescence spectroscopy, fluorescence emission spectra,
and UV–vis absorption spectra. The interaction between CdTe quantum dots and trypsin resulted in structure changes of trypsin
and inhibited trypsin's activity. Fluorescence emission spectra revealed that the quenching mechanism of trypsin by CdTe quantum
dots was a static quenching process. The binding constant and the number of binding sites at 288 and 298 K were calculated
to be 1.98 × 106 L mol−1 and 1.37, and 6.43 × 104 L mol−1 and 1.09, respectively. Hydrogen bonds and van der Waals' forces played major roles in this process. 相似文献
1000.
Li Huang Yiqun Ye Yuchao Zhang Aihong Zhang Tingting Liu Jiashu Cao 《Annals of botany》2009,104(7):1339-1351