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1.
YUNSHENG LOU KAZUYUKI INUBUSHI TAKAYUKI MIZUNO TOSHIHIRO HASEGAWA YANHUNG LIN HIDEMITSU SAKAI WEIGUO CHENG KAZUHIKO KOBAYASHI 《Global Change Biology》2008,14(11):2678-2687
A pot experiment was conducted to investigate CH4 emissions from a sandy paddy soil as influenced by rice cultivars and atmospheric CO2 elevation. The experiment with two CO2 levels, 370 μL L−1 (ambient) and 570 μL L−1 (elevated), was performed in a climatron, located at the National Institute for Agro‐Environmental Sciences, Tsukuba, Japan. Four rice cultivars were tested in this experiment, including IR65598, IR72, Dular and Koshihikari. Tiller number, root length and grain yield were clearly larger under elevated CO2 than under ambient CO2. IR72 and Dular showed significantly higher tiller number, root length and grain yield than Koshihikari and IR65598. Average daily CH4 fluxes under elevated CO2 were significantly larger by 10.9–23.8% than those under ambient CO2, and varied with the cultivars in the sequence Dular ≧ IR72>IR65598 ≧ Koshihikari. Dissolved organic C (DOC) content in the soil was obviously higher under elevated CO2 than under ambient CO2 and differed among the cultivars, in the sequence IR72>Dular>Koshihikari>IR65598. The differences in average daily CH4 fluxes between CO2 levels and among the cultivars were related to different root exudation as DOC content, root length and tiller number. This study indicated that Koshihikari should be a potential cultivar for mitigating CH4 emission and simultaneously keeping stable grain yield, because this cultivar emitted lowest CH4 emission and produced medium grain yield. 相似文献
2.
N Mei 《Archives internationales de physiologie et de biochimie》1988,96(3):A92-A98
The recent works showing the richness and complexity of the sensory innervation of viscera raise various questions which are of general interest for modern physiology. 1 - The primary afferent neurons are much more numerous and heterogeneous than it was usually expected. Moreover, another category of neurones, namely the sensory intrinsic neurons, must be taken in consideration. These neurones end either in the intrinsic plexuses of viscera or in the prevertebral ganglia. 2 - Another major question concerns the mechanisms responsible for the functional diversity of interoceptors including the chemoreceptors. Several hypothesis have been proposed involving the presence of membrane receptors, the release of neurotransmitters by chromaffin cells and the deformation of tissue. In any way, the functional characteristics of interoceptors do not result in morphological differentiation since free endings are mainly found in the visceral area. 3 - Does the functional properties of primary afferent neurons are related to their morphological (diameter of fibres, size of cell bodies) or their biochemical (type of neurotransmitters) characteristics? So far, it is not possible to answer this question. Nevertheless the available data suggest that a such relationship partly exists. 4 - The visceral afferents are largely implicated in various physiological mechanisms involving visceral motility, homeostasis and behaviour. Therefore, their role in pain appear relatively less important than previously expected. Conversely, the nervous mechanisms induced by the interoceptor activation play a major part in that they prepare and potentialize the effects produced by the other mechanisms. 相似文献
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Mei Wang Peter J.M. Van Haastert Panline Scbaap 《Differentiation; research in biological diversity》1987,33(3):24-28
Abstract. The effects of the differentiation inducing factor (DIF) on several CAMP-induced responses in Dictyostelium were investigated. It was found that DIF reduces the apparent affinity of cell-surface cAMP receptors. DIF does not affect the CAMP-induced cGMP response, but it is a potent inhibitor of the CAMP-relay response. DIF also inhibits the induction of prespore differentiation by cAMP in aggregation-competent cells. We also compared the effects of DIF on CAMP-induced responses with those of the relay inhibitor, caffeine, and the morphogen, adenosine. 相似文献
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Autophagy induction by xanthoangelol exhibits anti‐metastatic activities in hepatocellular carcinoma
Xiuwei Yang Jing Xie Xiaoxiao Liu Zichao Li Kun Fang Luying Zhang Mei Han Zhuang Zhang Zhi Gong Xuezhu Lin Xianzhou Shi Hui Gao Kui Lu 《Cell biochemistry and function》2019,37(3):128-138
Xanthoangelol (XAG), a prenylated chalcone isolated from the Japanese herb Angelica keiskei Koidzumi, has been reported to exhibit antineoplastic properties. However, the specific anti‐tumor activity of XAG in human hepatocellular carcinoma (HCC), and the relevant mechanisms are not known. Herein, we evaluated the effect of XAG against HCC in vitro and in vivo. Although XAG treatment did not significantly reduce the viability of the Hep3B and Huh7 cell lines, it suppressed cell migration, invasion, and EMT. This anti‐metastatic effect of XAG was due to induction of autophagy, because treatment with the autophagy inhibitor 3‐methyadenine (3‐MA) or knockdown of the pro‐autophagy Beclin‐1 effectively abrogated the XAG‐induced suppression of metastasis. Mechanistically, XAG induced autophagy via activation of the AMPK/mTOR signaling pathway, and XAG treatment dramatically increased the expression of p‐AMPK while decreasing p‐mTOR expression. In addition, blocking AMPK/mTOR axis with compound C abrogated the autophagy‐mediated inhibition of metastasis. The murine model of HCC metastasis also showed that XAG effectively reduced the number of metastatic pulmonary nodules. Taken together, our results revealed that autophagy via the activation of AMPK/mTOR pathway is essential for the anti‐metastatic effect of XAG against HCC. These findings not only contribute to our understanding of the anti‐tumor activity of XAG but also provide a basis for its clinical application in HCC. Before this study, evidence of XAG on HCC was purely anecdotal; present study provides the first comprehensive assessments of XAG on HCC metastasis and investigates its underlying mechanism. Results suggest that XAG exerts anti‐metastatic properties against HCC through inducing autophagy which is mediated by the activation of AMPK/mTOR signaling pathway. This research extends our knowledge about the antineoplastic properties of XAG and suggests that induction autophagy may represent future treatment strategies for metastatic HCC. 相似文献
9.
Weiduan Xu Jianmin Chen Glenn Yamasaki John E. Murphy Baisong Mei 《Molecular biotechnology》2010,45(3):248-256
Many therapeutic proteins require appropriate glycosylation for their biological activities and plasma half life. Coagulation
factor VIII (FVIII) is a glycoprotein which has extensive post-translational modification by N-linked glycosylation. The terminal
sialic acid in the N-linked glycans of FVIII is required for maximal circulatory half life. The extent of FVIII sialylation
can be determined by high pH anion-exchange chromatography coupled with a pulse electrochemical detector (HPAEC-PED), but
this requires a large amount of purified protein. Using FVIII as a model, the objective of the present study was to develop
assays that enable detection and prediction of sialylation deficiency at an early stage in the process and thus prevent downstream
product quality excursions. Lectin ECA (Erythrina Cristagalli) binds to unsialylated Galβ1-4 GlcNAc and the ECA-binding level (i.e., terminal Gal(β1-4) exposure) is inversely proportional
to the level of sialylation. By using ECA, a cell-based assay was developed to measure the global sialylation profile in FVIII
producing cells. To examine the Galβ1-4 exposure on the FVIII molecule in bioreactor tissue culture fluid (TCF), an ELISA-based
ECA-FVIII binding assay was developed. The ECA-binding specificity in both assays was assessed by ECA-specific sugar inhibitors
and neuraminidase digestion. The ECA-binding specificity was also independently confirmed by a ST3GAL4 siRNA knockdown experiment.
To establish the correlation between Galβ1-4 exposure and the HPAEC-PED determined FVIII sialylation value, the FVIII containing
bioreactor TCF and the purified FVIII samples were tested with ECA ELISA binding assay. The results indicated an inverse correlation
between ECA binding and the corresponding HPAEC-PED sialylation value. The ECA-binding assays are cost effective and can be
rapidly performed, thereby making them effective for in-process monitoring of protein sialylation. 相似文献
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