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961.
A. B. Imbs V. G. Rybin V. I. Kharlamenko L. P. T. Dang N. T. Nguyen K. M. Pham L. Q. Pham 《Russian Journal of Marine Biology》2015,41(6):461-467
A method that uses marker fatty acids (FAs) is widely applied in investigations of trophic and symbiotic relationships. In a search for new lipid markers, we determined the total lipid FA composition, as well as the composition of molecular species of mono- and digalactosyl diacylglycerols (MGDGs and DGDGs), which are specific galactolipids of thylakoid membranes, in zooxanthellae (endosymbiotic dinoflagellates) of the tropical soft coral Capnella sp. Some FAs of zooxanthellae were suggested for use as marker polyunsaturated FAs (PUFAs). Thirteen molecular species of MGDGs and ten molecular species of DGDGs were detected using the method of high-resolution tandem mass spectrometry. All marker PUFAs of zooxanthellae were found in acyl groups of galactolipids. The major molecular species of DGDGs (18:4/18:4, 18:4/20:5, and 16:2/22:6) and the unique molecular species of MGDGs (16:4/18:5) were described. The identification of several polyunsaturated molecular species of galactolipids that contain marker FAs allowed us to propose that this lipid group be used as molecular lipid markers of zooxanthellae for the study of symbiont–host interactions in soft corals. 相似文献
962.
Yang Wang Mingzhu Li Huizeng Li Yangjie Lan Xue Zhou Chang Li Xiaotian Hu Yanlin Song 《Liver Transplantation》2019,9(25)
Novel photovoltaic perovskite solar cells (PSCs) with high‐efficient photovoltaic property are largely in thrall to the uncertain perovskite grain size and inevitable defects. Here, inspired by the competitive growth between tree and grass in the forest system, a competitive perovskite grain growth approach via micro‐contact print (MicroCP) method (CD disk as templates) for printing wettability‐patterned substrate is proposed, aiming to achieve large‐grained perovskite and avoid discontinuous perovskite films caused by the low wettability of substrates. A MicroCP process is employed to construct a patterned wettability surface for the perovskite competitive growth mechanism on the electrode surface. This approach modifies the substrates quickly, ensures the uniform coverage of perovskite due to the function of ‐NH2 and Pb2+ bonds, and converts the perovskite films composed of small grains and pinholes into high‐quality perovskite films, free from pinholes and made up of large grains, resulting in efficiencies over 20% for the MicroCP PSCs. 相似文献
963.
Rheumatoid arthritis (RA) is a chronic inflammatory disorder that can, in severe cases, lead to disability. CC chemokine receptor (CCR), an integral membrane protein, has been suggested to play a key role in the RA developmentThis study is to explore the role of CCR5 silencing in inflammatory response, viability, and apoptosis of synovial cells in RA rats by inactivating the mitogen-activated protein kinase (MAPK) signaling pathway. Microarray analysis was conducted to screen out differentially expressed genes from RA-related chips. The rat model was established by injection of siRNA-CCR5 and PD98059 (inhibitor of mitogen-activated protein kinase kinase 1) to evaluate the role of CCR5 silencing in RA, with the involvement of inflammatory response, synovial cell viability, apoptosis, and cycle. CCR5 was predicted to participate in RA by regulating the MARK pathway. In animal experiments, reduction was identified in arthritis index (AI), CCR5 positive expression rate, levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), matrix metalloproteinase (MMP)-1, and MMP-3 in serum of RA rats after CCR5 siRNA and PD98059 injections. RA rats treated with CCR5 siRNA, and PD98059 presented with inhibition in cell viability, promotion of apoptosis, increase in cell proportion in G0/G1 phase, and shortened the S phase. In addition, the treatment of CCR5 siRNA, and PD98059 resulted in downregulated JNK1, ERK1, p38, Cyclin D1, Cyclin E1, Cyclin B1, and Bcl-2 and upregulated Bax and Cas3. These findings reveal that CCR5 silencing suppresses inflammatory response, inhibits viability, and promotes apoptosis of synovial cells in RA rats by inhibiting MAPK pathway. Therefore, CCR5 silencing may provide a novel therapeutic target for RA. 相似文献
964.
Dinh T. Lam Bui C. Buu Nguyen T. Lang Kinya Toriyama Ikuo Nakamura Ryuji Ishikawa 《Ecology and evolution》2019,9(5):2964-2977
Oryza rufipogon Griff. is a perennial species of wild rice widely distributed along the channels and rivers of the Mekong Delta, Vietnam. This study attempted to find centers of diversity among wild rice populations in this area and their inter‐relationships. The highest genetic diversity was found in the Dong Thap population and the lowest in the Can Tho population. Maternal diversity evaluated using chloroplast INDELs detected ten plastid types, five of which were novel relative to other Asian countries. The mitochondrial genome suggested two unique deletions. One 699‐bp deletion via short tandem repeats was accompanied by another deletion including orf153. All accessions carrying the mitochondrial type were found in a particular plastid type. This unique maternal lineage was confined to specific channels where it showed vigorous vegetative growth in comparison to upstream areas where various maternal lineages and maximum genetic diversity occurred. This area along the Mekong Delta is a center of not only nuclear but also maternal diversity. 相似文献
965.
Bastien Dehaudt My Nguyen Arjun Vadlamudi Daniel T. Blumstein 《Ethology : formerly Zeitschrift fur Tierpsychologie》2019,125(6):392-398
It is often beneficial for animals to discriminate between different threats and to habituate to repeated exposures of benign stimuli. While much is known about risk perception in vertebrates and some invertebrates, risk perception in marine invertebrates is less extensively studied. One method to study risk perception is to habituate animals to a series of exposures to one stimulus, and then present a novel stimulus to test if it transfers habituation. Transfer of habituation is seen as a continued decrease in response while lack of transfer is seen either by having a similar or greater magnitude response. We asked whether giant clams (Tridacna maxima) discriminate between biologically relevant types of threats along a risk gradient. Giant clams retract their mantle and close their shell upon detecting a threat. While closed, they neither feed nor photosynthesize, and prior work has shown that the cost of being closed increases as the duration of their response increases. We recorded a clam's latency to emerge after simulated threats chosen to represent a risk gradient: exposure to a small shading event, a medium shading event, a large shading event (chosen to simulate fish swimming above them), tapping on their shell and touching their mantle (chosen to simulate different degrees of direct attack). Although these stimuli are initially perceived as threatening, we expected clams to habituate to them because they are ultimately non‐damaging and it would be costly for clams to remain closed for extended periods of time when there is no threat present. Clams had different initial latencies to emerge and different habituation rates to these treatments, and they did not transfer habituation to higher risk stimuli and to some lower risk stimuli. These results suggest that clams discriminated between these stimuli along a risk gradient and the lack of habituation transfer shows that the new stimulus was perceived as a potential threat. This study demonstrates that sessile bivalves can discern between levels of predatory threat. These photosynthetic clams may benefit from being able to categorize predator cues for efficient energy allocation. 相似文献
966.
肺纤维化(pulmonary fibrosis, PF)是临床常见的一种慢性进行性呼吸系统疾病,以中晚期出现肺组织的纤维化为病变特征。由于肺纤维化病因复杂,其发病机制至今仍不明确,这也成为该疾病治疗的最大难点,并且由于该病的高死亡率,寻求有效的治疗方法迫在眉睫。随着现代分子生物学技术的广泛应用以及对该疾病的发生机制和病理生理变化研究的不断深入,发现AMPK、mTOR和JNK等相关信号通路以及ECM沉积和氧化应激等在肺纤维化发病机制中起着重要作用。因此,针对这些通路中的相关分子的靶点治疗将成为肺纤维化治疗的新趋势。本文旨在对肺纤维化治疗相关的细胞因子以及micro RNA分子靶点研究进展做一总结,为防治肺纤维化提供新的理论依据,同时为临床诊疗提供参考。 相似文献
967.
Biochar,Bentonite and Zeolite Supplemented Feeding of Layer Chickens Alters Intestinal Microbiota and Reduces Campylobacter Load 总被引:1,自引:0,他引:1
Tanka P. Prasai Kerry B. Walsh Surya P. Bhattarai David J. Midmore Thi T. H. Van Robert J. Moore Dragana Stanley 《PloS one》2016,11(4)
A range of feed supplements, including antibiotics, have been commonly used in poultry production to improve health and productivity. Alternative methods are needed to suppress pathogen loads and maintain productivity. As an alternative to antibiotics use, we investigated the ability of biochar, bentonite and zeolite as separate 4% feed additives, to selectively remove pathogens without reducing microbial richness and diversity in the gut. Neither biochar, bentonite nor zeolite made any significant alterations to the overall richness and diversity of intestinal bacterial community. However, reduction of some bacterial species, including some potential pathogens was detected. The microbiota of bentonite fed animals were lacking all members of the order Campylobacterales. Specifically, the following operational taxonomic units (OTUs) were absent: an OTU 100% identical to Campylobacter jejuni; an OTU 99% identical to Helicobacter pullorum; multiple Gallibacterium anatis (>97%) related OTUs; Bacteroides dorei (99%) and Clostridium aldenense (95%) related OTUs. Biochar and zeolite treatments had similar but milder effects compared to bentonite. Zeolite amended feed was also associated with significant reduction in the phylum Proteobacteria. All three additives showed potential for the control of major poultry zoonotic pathogens. 相似文献
968.
969.
本文研究了锌离子存在下EGCG对前列腺癌细胞PC-3生长的影响.研究发现Zn^2+可以增强EGCG抗癌活性,Zn^2+存在下。EGCG处理后前列腺癌细胞PC-3克隆形成率显著下降。以RT—PCR、免疫组化方法研究Zn^2+、EGCG对67kD层粘连蛋白受体(67kD Laminin Receptor,67LR)表达调控,结果表明Znn可通过上调67LR的表达,为EGCG提供更多作用的靶位点,增强EGCG对前列腺癌细胞PC-3的毒性作用。MMP-9是肿瘤侵袭转移过程中关键的基质金属蛋白酶。MMP-9活性与癌细胞的转移潜能密切相关。本文研究发现Zn^2+、EGCG处理可通过抑制MMP-9活性,降低前列腺癌细胞PC-3的迁移率.其中80umol/LEGCG+80umol/L Zn^2+处理24h后显著抑制了PC-3细胞的迁移率。 相似文献
970.
Ten year after its discovery Survivin has gained a strategic place within the chromosomal passenger complex. Whereas INCENP, Borealin and Aurora B are fully immobile in the complex, Survivin is mobile on centromere. Its mobility is regulated both by phosphorylation and ubiquitination. Survivin is a dynamic messenger that senses the central spindle tension and participates to the control of the mitotic chekpoint. In this review, we have detailed the multiple mitotic activities of Survivin and discussed them in light of the recent reported crystallographic data. 相似文献