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881.
Stephan Herget Philip V Toukach René Ranzinger William E Hull Yuriy A Knirel Claus-Wilhelm von der Lieth 《BMC structural biology》2008,8(1):35
Background
There are considerable differences between bacterial and mammalian glycans. In contrast to most eukaryotic carbohydrates, bacterial glycans are often composed of repeating units with diverse functions ranging from structural reinforcement to adhesion, colonization and camouflage. Since bacterial glycans are typically displayed at the cell surface, they can interact with the environment and, therefore, have significant biomedical importance. 相似文献882.
A marine fish cell line from the snout of red spotted grouper Epinephelus akaara, a protogynous hermaphrodite, was established, characterized, and subcultured with more than 60 passages. The grouper snout
cell line (GSC) cells multiplied well in Dulbecco’s modified Eagle’s medium (DMEM) medium supplemented with 10% fetal bovine
serum. The optimal growth temperature was 25°C, and morphologically the cells were fibroblastic. Chromosome analysis revealed
that the GSC cell line has a normal diploid karyotype with
. A virus titration study indicated that the cells were susceptible to turbot Scophthalmus Maximus rhabdovirus (SMRV) (108.5 TCID50 ml−1), while the viral titer of frog Rana grylio virus 9807 (RGV9807) reached 103.5 TCID50 ml−1. The infection was confirmed by cytopathic effect (CPE), immunofluorescence, and electron microscopy experiments, which detected
the viral particles in the cytoplasm of virus-infected cells, respectively. Further, significant fluorescent signals were
observed when the GSC cells were transfected with pEGFP vector DNA, indicating their potential utility for transgenic and
genetic manipulation studies. 相似文献
883.
Joon Sang Lee 《Journal of Plant Biology》2010,53(1):19-23
Stomata usually open when leaves are transferred from darkness to light. However, reverse-phase stomatal opening in succulent
plants has been known. CAM plants such as cacti and Opuntia ficus–indica achieve their high water use efficiency by opening their stomata during the cool, desert nights and closing them during the
hot, dry days. Signal transduction pathway for stomatal opening by blue light photoreceptors including phototropins and the
carotenoid pigment zeaxanthin has been suggested. Blue light regulated signal transduction pathway on stomatal opening could
not be applied to CAM plants, but the most possible theory for a nocturnal response of stomata in CAM plants is photoperiodic
circadian rhythm. 相似文献
884.
Ying Wang Yunjing Zhang Xinwan Su Qiongzi Qiu Yuan Yuan Chunhua Weng Sailan Zou Yan Tian Weidong Han Pengyuan Liu Xingyi Guo Jianhua Mao Xianghui Fu Ping Wang Weiqiang Lin 《International journal of biological sciences》2022,18(4):1491
Clear cell renal cell carcinoma (ccRCC) is a primary kidney cancer with high aggressive phenotype and extremely poor prognosis. Accumulating evidence suggests that circular RNAs (circRNAs) play pivotal roles in the occurrence and development of various human cancers. However, the expression, clinical significance and regulatory role of circRNAs in ccRCC remain largely unclear. Here we report that circDVL1 to be reduced in the serums and tissues from ccRCC patients, and to negatively correlate with ccRCC malignant features. Overexpression of circDVL1 inhibits proliferation, induces G1/S arrest, triggers apoptosis, and reduces migration and invasion in different ccRCC cells in vitro. Correspondingly, circDVL1 overexpression suppresses ccRCC tumorigenicity in a mouse xenograft model. Mechanistically, circDVL1 serves as a sponge for oncogenic miR-412-3p, thereby preventing miR-412-3p-mediated repression of its target protocadherin 7 (PCDH7) in ccRCC cells. Collectively, our results demonstrate that circDVL1 exerts tumor-suppressive function during ccRCC progression through circDVL1/miR-412-3p/PCDH7 axis, and suggest that circDVL1 could be a novel diagnostic and prognositc marker and therapeutic target for ccRCC. 相似文献
885.
In this paper, the global robust stability problem of delayed Takagi–Sugeno fuzzy Hopfield neural networks with discontinuous
activation functions (TSFHNNs) is considered. Based on Lyapunov stability theory and M-matrices theory, we derive a stability criterion to guarantee the global robust stability of TSFHNNs. Compared with the existing
literature, we remove the assumptions on the neuron activations such as Lipschitz conditions, bounded, monotonic increasing
property or the assumption that the right-limit value is bigger than the left one at the discontinuous point. Finally, two
numerical examples are given to show the effectiveness of the proposed stability results. 相似文献
886.
887.
Naja Becher Merete Hein Carl C Danielsen Niels Uldbjerg 《Reproductive biology and endocrinology : RB&E》2010,8(1):113
Background
High concentrations of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) have been identified in the cervical mucus plug (CMP) at term of pregnancy. Their physiological and pathophysiological implications, however, remain to be elucidated, and CMPs from preterm labor have never been examined. This study was therefore conducted to describe the concentrations of MMP-2, TIMP-1, MMP-8 and MMP-9 in the CMP in relation to gestational age, IL-8 as an indicator of inflammation, compartment of the CMP, and preterm labor. 相似文献888.
Mehran Dastmalchi Myung Ryeol Park Jeremy S. Morris Peter Facchini 《Phytochemistry Reviews》2018,17(2):249-277
Benzylisoquinoline alkaloids (BIAs) are a group of specialized metabolites found predominantly in the plant order Ranunculales. Approximately 2500 naturally occurring BIAs have been identified, many of which possess a variety of potent biological and pharmacological properties. The initial BIA skeleton is formed via condensation by a unique enzyme, norcoclaurine synthase, of the l-tyrosine derivatives dopamine and 4-hydroxyphenylacetaldehyde, yielding (S)-norcoclaurine as a central intermediate. The vast diversity of BIA structures is subsequently derived from (1) transformation of the basic BIA backbone by oxidative enzymes, particularly cytochromes P450 and FAD-linked oxidases, and (2) further structural and functional group modification by tailoring enzymes, which also include various reductases, dioxygenases, acetyltransferases, and carboxylesterases. Most of the biosynthetic enzymes responsible for the biosynthesis of major BIAs (i.e. morphine, noscapine, papaverine, and sanguinarine) in opium poppy (Papaver somniferum), and other compounds (e.g. berberine) in related plants, have been isolated and partially characterized. Diversity in BIA metabolism is driven by the modular and repetitive recruitment, and subsequent neo-functionalization, of a limited number of ancestral enzymes. In this review, BIA biosynthetic enzymes are discussed in the context of their respective families, facilitating exploration of common phylogeny and biochemical mechanisms. 相似文献
889.
Khrenova M Domratcheva T Grigorenko B Nemukhin A 《Journal of molecular modeling》2011,17(7):1579-1586
The first biochemical and structural characterization of the full-length active photoreceptor BlrP1 from Klebsiella pneumoniae was recently reported by Barends et al. [Nature 459:1015–1018, (2009)]. The light-regulated catalytic function of its C-terminal c-di-guanosine monophosphate phosphodiesterase, the EAL (Glu-Ala-Leu)
domain, is activated by the N-terminal sensor of blue light using the flavin adenine dinucleotide (BLUF) domain. We performed
molecular dynamics simulations on the dimeric BlrP1 protein in order to examine the coupling regions that are presumably involved
in transmitting light-induced structural changes which occur in the BLUF domain to the EAL domain. According to the results
of simulations and an analysis of the hydrogen bonding between the respective polypeptide chains, the region containing the
site on the α3α4 loop of BLUF is responsible for communication between the photosensing and catalytic domains in the dimeric
BlrP1 protein. 相似文献
890.