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991.
This paper describes the real-time quantification of Pseudomonas aeruginosa (P. aeru) concentrations using a wireless magnetoelastic sensing device. The sensor is fabricated by coating a magnetoelastic ribbon with a polyurethane protecting film. In response to an externally applied time varying magnetic field, the magnetoelastic sensor vibrates at a resonance frequency that can be remotely determined by monitoring the magnetic flux emitted by the sensor. The resonance frequency changes in response to properties changes of a liquid culture medium and bacteria adhesion to the sensor as P. aeru consumes nutrients from the culture medium in growth and reproduction. The effects of properties (conductivity, viscosity, mass) are investigated with quartz crystal microbalance (QCM), microscopy imaging, and conductivity measurement. Using the described technique we are able to directly quantify P. aeru concentrations of 10(3) to 10(8)cells/ml, with a detection limit of 10(3)cells/ml at a noise level of approximately 20 Hz. The lack of any physical connections between the sensor and the monitoring electronics facilitates aseptic operation, and makes the sensor platform ideally suited for monitoring bacteria from within, for example, sealed food containers. 相似文献
992.
Multiple conserved domains of the nucleoporin Nup124p and its orthologs Nup1p and Nup153 are critical for nuclear import and activity of the fission yeast Tf1 retrotransposon 下载免费PDF全文
The nucleoporin Nup124p is a host protein required for the nuclear import of both, retrotransposon Tf1-Gag as well as the retroviral HIV-1 Vpr in fission yeast. The human nucleoporin Nup153 and the Saccharomyces cerevisiae Nup1p were identified as orthologs of Nup124p. In this study, we show that all three nucleoporins share a large FG/FXFG-repeat domain and a C-terminal peptide sequence, GRKIxxxxxRRKx, that are absolutely essential for Tf1 retrotransposition. Though the FXFG domain was essential, the FXFG repeats themselves could be eliminated without loss of retrotransposon activity, suggesting the existence of a common element unrelated to FG/FXFG motifs. The Nup124p C-terminal peptide, GRKIAVPRSRRKR, was extremely sensitive to certain single amino acid changes within stretches of the basic residues. On the basis of our comparative study of Nup124p, Nup1p, and Nup153 domains, we have developed peptides that specifically knockdown retrotransposon activity by disengaging the Tf1-Gag from its host nuclear transport machinery without any harmful consequence to the host itself. Our results imply that those domains challenged a specific pathway affecting Tf1 transposition. Although full-length Nup1p or Nup153 does not complement Nup124p, the functionality of their conserved domains with reference to Tf1 activity suggests that these three proteins evolved from a common ancestor. 相似文献
993.
Pang Lujun Liu Zhao Zhou Ke Chen Peng Pan Enyu Che Yanjun Qi Xin 《Neurochemical research》2022,47(3):601-612
Neurochemical Research - Subarachnoid hemorrhage (SAH) is one of the life-threatening neurosurgical diseases in central nervous system. Autophagy has been previously demonstrated to exert vital... 相似文献
994.
Journal of Applied Phycology - The temperature tolerance of Gracilariopsis lemaneiformis cultivated for nearly 35 years was compared to its wild-type counterpart after exposing them for 24-h to... 相似文献
995.
Journal of Applied Phycology - Phlorotannins are among the most important defensive molecules in kelp. They have been majorly identified in brown algae so far. Type III polyketide synthase (PKS) is... 相似文献
996.
997.
Qichen Yang MSc Vishal Jhanji MD Sze Qin Tan BSc Kwok Ping Chan BSc Di Cao PhD Wai Kit Chu DPhil Mingzhi Zhang MD Chi Pui Pang DPhil Tsz Kin Ng PhD 《Journal of cellular biochemistry》2019,120(3):4203-4213
Pterygium is a triangular-shaped hyperplastic growth, characterized by conjunctivalization, inflammation, and connective tissue remodeling. Our previous meta-analysis found that cigarette smoking is associated with a reduced risk of pterygium. Yet, the biological effect of cigarette smoke components on pterygium has not been studied. Here we reported the proliferation and migration properties of human primary pterygium cells with continuous exposure to nicotine and cotinine. Human primary pterygium cells predominantly expressed the α5, β1, and γ subunits of the nicotinic acetylcholine receptor. Continuous exposure to the mixture of 0.15 μM nicotine and 2 μM cotinine retarded pterygium cell proliferation by 16.04% (P = 0.009) and hindered their migration by 11.93% ( P = 0.039), without affecting cell apoptosis. SNAIL and α-smooth muscle actin protein expression was significantly downregulated in pterygium cells treated with 0.15 μM nicotine-2 μM cotinine mixture by 1.33- ( P = 0.036) and 1.31-fold ( P = 0.001), respectively. Besides, the 0.15 μM nicotine-2 μM cotinine mixture also reduced matrix metalloproteinase (MMP)-1 and MMP-9 expressions in pterygium cells by 1.56- ( P = 0.043) and 1.27-fold ( P = 0.012), respectively. In summary, this study revealed that continuous exposure of nicotine and cotinine inhibited human primary pterygium cell proliferation and migration in vitro by reducing epithelial-to-mesenchymal transition and MMP protein expression, partially explaining the lower incidence of pterygium in cigarette smokers. 相似文献
998.
999.
Xinlu Pang Guiwen Feng Wenjun Shang Lei Liu Jingfeng Li Yonghua Feng Hongchang Xie Junxiang Wang 《Journal of cellular biochemistry》2019,120(8):12822-12831
Early damage to transplanted organs initiates excess inflammation that deteriorates existing injury, which is a leading cause of graft loss. Long noncoding RNAs (lncRNAs) are recently thought to play a significant role in cellular homeostasis during pathological process of kidney diseases. The aim of this study was to assess the function and mechanism of lncRNA, maternally expressed gene 3 (MEG3), on early renal allografts pathogenesis. Real-time polymerase chain reaction (RT-PCR) analysis found that the levels of MEG3 and miR-181b-5p were increased and decreased respectively in grafted kidney. The Western blot assay showed that TNF-alpha was upregulated in the kidney and in HK-2 cells. Administering MEG3-specific small interfering RNA (siRNA) in mice silenced MEG3 expression and protected kidney renal allograft from injury. Bioinformatical analysis and luciferase assay indicated that MEG3 is a target of miR-181b-5p. MEG3 inhibition and overexpression promoted and suppressed miR-181b-5p levels respectively. In addition, Western blot and immunohistochemical staining suggested that decreased TNF-alpha expression was observed in the kidney. In contrary to MEG3, miR181b overexpression attenuated hypoxia-induced HK-2 cell apoptosis, as well as suppressed hypoxia-induced TNF-alpha upregulation. In luciferase reporter assay, we confirmed that miR-181b directly bound to the 3′-untranslated region (3′-UTR) of TNF-alpha, thereby negatively regulating the TNF-alpha expression. Our data suggested that MEG3 functions as a competing endogenous RNA for miR-181b to regulate the TNF-alpha expression in hypoxia-induced kidney injury in acute renal allografts. 相似文献
1000.
Kaiping Deng Caifang Ren Yixuan Fan Jing Pang Guomin Zhang Yanli Zhang Peihua You Feng Wang 《Journal of cellular biochemistry》2019,120(12):19578-19589
Adipose tissue development is regulated by a serial of developmental signaling pathways. The Hippo pathway is a novel signaling cascade closely associated with adipogenesis. While most of Hippo pathway components had been verified that have a vital role in preadipocytes proliferation and differentiation, little is known about the function of Yes-associated protein 1 (YAP1) in mammalian adipose tissue development. Therefore, we investigated the role of YAP1 in ovine adipose tissue development by in vitro and in vivo experiments. We observed that the adipocyte size in subcutaneous adipose tissue increased with development. YAP1 expression increased during adipose tissue development, while decreased during the differentiation of ovine preadipocytes in vitro. YAP1 knockdown notably promoted lipid accumulation and suppressed ovine preadipocyte proliferation. In addition, we observed that YAP1 deficiency significantly upregulated peroxisome proliferator-activated receptor gamma (PPARG) and retinoid X receptor alpha (RXR alpha) expression. By contrast, overexpression of YAP1 led to the suppression of preadipocyte differentiation, lipid droplets formation, and PPARG expression. In brief, our findings demonstrated that YAP1 regulates the proliferation and differentiation of ovine preadipocyte via altering PPARG and RXR alpha expression. 相似文献