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991.
Won Yong Jung Haneul Kim Se Jin Jeon Hye Jin Park Hyuck Jai Choi Nam Jae Kim Dong Hyun Kim Dae Sik Jang Jong Hoon Ryu 《Neurochemical research》2018,43(2):351-362
Eclalbasaponin II derived from Eclipta prostrata L. (Asteraceae) has been reported to have anti-fibrotic, anti-bacterial and autophagic activities, but its effect on cognitive function has not been investigated. We studied the effect of eclalbasaponin II on cholinergic blockade-induced memory impairment in mice using the passive avoidance, Y-maze, and Morris water maze tasks. Eclalbasaponin II (10 or 20 mg/kg, p.o.) significantly ameliorated the cognitive dysfunction induced by scopolamine in the passive avoidance, Y-maze, and the Morris water maze tasks. To identify the mechanism of the memory-ameliorating effect of eclalbasaponin II, acetylcholinesterase (AChE) activity assay, Western blot analysis and electrophysiology were conducted. Eclalbasaponin II inhibited the AChE activity in ex vivo study, and the administration of eclalbasaponin II and its metabolite, echinocystic acid, increased the phosphorylation levels of memory-related signaling molecules, including protein kinase B (Akt) and glycogen synthase kinase-3β (GSK-3β), in the hippocampus. Although eclalbasaponin II did not affect hippocampal long term potentiation (LTP), echinocystic acid significantly enhanced hippocampal LTP formation (30 μM). These results suggest that eclalbasaponin II ameliorates cholinergic blockade-induced cognitive impairment via AChE inhibition, LTP formation and the activation of Akt-GSK-3β signaling, and that eclalbasaponin II may be a useful to treat cognitive impairment derived from cholinergic dysfunction. 相似文献
992.
Qingzhi Wang Fengjuan Jiao Pei Zhang Jianguo Yan Zheng Zhang Feng He Qian Zhang Zexi Lv Xiang Peng Hongwei Cai Bo Tian 《Molecular neurobiology》2018,55(5):3709-3717
The molecular mechanisms responsible for the loss of dopaminergic neurons in Parkinson’s disease (PD) remain obscure. Loss of function of E3 ubiquitin ligases is associated with mitochondria dysfunction, dysfunction of protein degradation, and α-synuclein aggregation, which are major contributors to neurodegeneration in PD. Recent research has thus focused on E3 ubiquitin ligase glycoprotein 78 (GP78); however, the role of GP78 in PD pathogenesis remains unclear. Notably, cyclin-dependent kinase 5 (CDK5) controls multiple cellular events in postmitotic neurons, and CDK5 activity has been implicated in the pathogenesis of PD. Thus, we addressed the relationship between CDK5 and GP78 in MPTP-based PD models. We found that GP78 expression is decreased in MPTP-based cellular and animal PD models, and CDK5 directly phosphorylated GP78 at Ser516, which promoted the ubiquitination and degradation of GP78. Importantly, overexpression of GP78 or interference of GP78 Ser516 phosphorylation protected neurons against MPP+-induced cell death. Thus, our research reveals that the CDK5-GP78 pathway is involved in the pathogenesis of PD and could be a novel candidate drug target for the treatment of PD. 相似文献
993.
Microbial decolorization of spentwash: a review 总被引:1,自引:0,他引:1
Spentwash is one of the most complex and cumbersome wastewater with very high BOD, COD and other organic and inorganic toxic
constituents. It is dark brown colored and difficult to treat by normal biological process such as activated sludge or anaerobic
lagooning. The color is due to the presence of melanoidins, caramels and other polymers. These compounds have anti oxidant
properties which render them toxic to microorganisms. Spentwash disposal into the environment is hazardous and has a considerable
pollution potential. It affects the aesthetic merit. Its decolorization by physical or chemical methods have been investigated
and were found unsuitable. In the recent past, increasing attention has been directed towards utilizing microbial activity
for decolorization of spentwash. This review reveals various groups of microorganisms which have potential in spentwash decolorization.
The role of enzymes in decolorization and the microbial degradation of individual compounds imparting color to spentwash are
also discussed. 相似文献
994.
Sun QiangLing Liu YinKun Lu WenJing Cheng Gang Zhou HaiJun Zhou XinWen Wei LiMing Dai Zhi Guo Kun Lu HaoJie 《中国科学C辑(英文版)》2007,50(3):403-411
In order to establish the novel high throughput, high efficiency and low cost technological platform for the research of N-glycoproteomics, to resolve the significance of characteristic expression profile of glycoprotein and to find the proteins
with biological functional importance, the glycoproteins with high-mannose core and the two antennary types were purified
and enriched by the Con A affinity chromatography. Con A affinity protein expression profiles of normal human liver tissue
were generated by using SDS-PAGE, two-dimensional electrophoresis (2-DE) followed by fast fluorescence staining based on multiplexed
proteomics (MP) technology. 301 visible protein spots on the gel were detected and 85 of glycoproteins were further successfully
identified via peptide mass fingerprinting (PMF) by a matrix assisted laser desorption/ionization time-of-flight mass spectrometry
(MALDI-TOF-MS/MS) and annotated to IPI databases. Identified glycoproteins definitely take part in the regulation of cell
cycle and metabolic processes. The glycosylation sites were predicted with NetNGlyc 1.0 and NetOGlyc 3.1 software, meanwhile
they were classified according to the geneontology methods. The construction of Con A affinity glycoprotein database of normal
human liver tissue would contribute to the subsequent research. 相似文献
995.
Cindy Q. Tang Mei-Hua Zhao Xiao-Shuang Li Masahiko Ohsawa Xiao-Kun Ou 《Ecological Research》2010,25(1):149-161
Since 1985, originally forested mountainous areas of China have been allowed to return to their natural state after years
of exploitation including agriculture, development, and logging. The reforms began earlier in less accessible locations, so
that today the successional process is more advanced there. The vegetation in Luquan, Qiongzhusi, and Xishan near Kunming,
central Yunnan, exhibits, in a limited area, a range of stages of plant succession that are widely encountered throughout
the broader region, and thus affords a special opportunity for a comprehensive study. We analyzed the successional sequence
of these various plant communities. They ranged from pioneer coniferous and/or pioneer deciduous broad-leaved stands to pre-mature
semi-humid evergreen broad-leaved stands, through mixed coniferous and broad-leaved or mixed deciduous and evergreen broad-leaved
stands. The succession proceeded from pioneer coniferous Pinus and Keteleeria, and deciduous Platycarya and Alnus, to late-successional evergreen broad-leaved Cyclobalanopsis and Castanopsis. Two regeneration types of woody species in either the early successional (15–50 years), the mid-successional (40–80 years),
or the late-successional (80–180 years) stage were classified. Relatively high species diversity was found in the seral phase
at the three study sites. The late-successional stage was commonest where human disturbance was least evident. Poor soil chemical
properties under pioneer Pinus were seen as a limitation to plant growth, while the abundance of Alnus at the early stage led to an improved level of organic matter and nitrogen. 相似文献
996.
Background
Non-invasive planar fluorescence reflectance imaging (FRI) is used for accessing physiological and molecular processes in biological tissue. This method is efficiently used to detect superficial fluorescent inclusions. FRI is based on recording the spatial radiance distribution (SRD) at the surface of a sample. SRD provides information for measuring structural parameters of a fluorescent source (such as radius and depth). The aim of this article is to estimate the depth and radius of the source distribution from SRD, measured at the sample surface. For this reason, a theoretical expression for the SRD at the surface of a turbid sample arising from a spherical light source embedded in the sample, was derived using a steady-state solution of the diffusion equation with an appropriate boundary condition. 相似文献997.
998.
Eukaryotic genomes are especially vulnerable to DNA damage during the S phase of the cell cycle, when chromosomes must be duplicated. The stability of DNA replication forks is critical to achieve faithful chromosome replication and is severely compromised when forks encounter DNA lesions. To maintain genome integrity, replication forks need to be protected by the S-phase checkpoint and DNA insults must be repaired. Different pathways help to repair or tolerate the lesions in the DNA, but their contribution to the progression of replication forks through damaged DNA is not well known. Here we show in budding yeast that, when the DNA template is damaged with the alkylating agent methyl methanesulfonate (MMS), base excision repair, homologous recombination and DNA damage tolerance pathways, together with a functional S-phase checkpoint, are essential for the efficient progression of DNA replication forks and the maintenance of cell survival. In the absence of base excision repair, replication forks stall reversibly in cells exposed to MMS. This repair reaction is necessary to eliminate the lesions that impede fork progression and has to be coordinated with recombination and damage tolerance activities to avoid fork collapse and allow forks to resume and complete chromosome replication. 相似文献
999.
We tested the pathogenicity of 18 Metarhizium anisopliae (Metschn.) Sorokin isolates and 22 Beauveria bassiana (Balsamo) Vuillemin isolates against Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae) larvae and adults. The efficacy of the most virulent isolate—M. anisopliae K—was evaluated in containers with a concrete bottom covered with wood shavings, under simulated poultry house conditions.
Application of conidia of this isolate to the shavings or directly to the concrete bottom reduced the yield of larvae in 8–15
time compared with the control. In another test, the mortality of mature larvae placed on previously inoculated shavings or
bottom reached 80–90% within 14 days, compared with 14% in the control. The residual activity of conidia kept at 28°C retained
its initial level during 14 days post-inoculation, but declined after three weeks. Based on our data M. anisopliae has considerable potential for the control of A. diaperinus.
相似文献
Michael SamishEmail: Email: |