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Yilin Tang Jingjie Ge Fengtao Liu Ping Wu Sisi Guo Zhenyang Liu Yixuan Wang Ying Wang Zhengtong Ding Jianjun Wu Chuantao Zuo Jian Wang 《PloS one》2016,11(4)
PurposeTo characterize cerebral glucose metabolism associated with different cognitive states in Parkinson’s disease (PD) using 18F-fluorodeoxyglucose (FDG) and Positron Emission Tomography (PET).MethodsThree groups of patients were recruited in this study including PD patients with dementia (PDD; n = 10), with mild cognitive impairment (PD-MCI; n = 20), and with no cognitive impairment (PD-NC; n = 30). The groups were matched for age, sex, education, disease duration, motor disability, levodopa equivalent dose and Geriatric Depression Rating Scale (GDS) score. All subjects underwent a FDG-PET study. Maps of regional metabolism in the three groups were compared using statistical parametric mapping (SPM5).ResultsPD-MCI patients exhibited limited areas of hypometabolism in the frontal, temporal and parahippocampal gyrus compared with the PD-NC patients (p < 0.01). PDD patients had bilateral areas of hypometabolism in the frontal and posterior parietal-occipital lobes compared with PD-MCI patients (p < 0.01), and exhibited greater metabolic reductions in comparison with PD-NC patients (p < 0.01).ConclusionsCompared with PD-NC patients, hypometabolism was much higher in the PDD patients than in PD-MCI patients, mainly in the posterior cortical areas. The result might suggest an association between posterior cortical hypometabolism and more severe cognitive impairment. PD-MCI might be important for early targeted therapeutic intervention and disease modification. 相似文献
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Luo Lilan He Yajun Zhao Yannan Xu Qian Wu Jian Ma Haiyan Guo Hongyan Bai Lin Zuo Jianru Zhou Jian-Min Yu Hong Li Jiayang 《中国科学:生命科学英文版》2019,62(8):991-1002
Reactive oxygen species(ROS) play a crucial role in numerous biological processes in plants, including development, responses to environmental stimuli, and programmed cell death(PCD). Deficiency in MOSAIC DEATH 1(MOD1), a plastid-localized enoyl-ACP reductase essential for de novo fatty acid biosynthesis in Arabidopsis thaliana, leads to the increased malate export from chloroplasts to mitochondria, and the subsequent accumulation of mitochondria-generated ROS and PCD. In this study, we report the identification and characterization of a mod1 suppressor, som592. SOM592 encodes mitochondrion-localized NAD~+ transporter 2(NDT2). We show that the mitochondrial NAD pool is elevated in the mod1 mutant. The som592 mutation fully suppressed mitochondrial NADH hyper-accumulation, ROS production, and PCD in the mod1 mutant, indicating a causal relationship between mitochondrial NAD accumulation and ROS/PCD phenotypes. We also show that in wild-type plants, the mitochondrial NAD+uptake is involved in the regulation of ROS production in response to continuous photoperiod. Elevation of the alternative respiration pathway can suppress ROS accumulation and PCD in mod1, but leads to growth restriction. These findings uncover a regulatory mechanism for mitochondrial ROS production via NADH homeostasis in Arabidopsis thaliana that is likely important for growth regulation in response to altered photoperiod. 相似文献
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Three PBDEs (BDE25, BDE47, and BDE154) were selected to investigate the interactions between PBDEs and hen egg white lysozyme (HEWL) by molecular modeling, fluorescence spectroscopy, and FT‐IR spectra. The docking results showed that hydrogen bonds were formed between BDE25 and residue TRP63 and between BDE47 and TRP63 with bond lengths of 2.178 Å and 2.146 Å, respectively. The molecular dynamics simulations indicated that van der Waals forces played a predominant role in the binding of three PBDEs to HEWL. The observed fluorescence quenching can be attributed to the formation of complexes between HEWL and PBDEs, and the quenching mechanism is a static quenching. According to Förster's non‐radiative energy transfer theory, the binding distances r were < 7 nm, indicating a high probability of energy transfer from HEWL to the three PBDEs. The synchronous fluorescence showed that the emission maximum wavelength of tryptophan (TRP) residues emerged a red‐shift. FT‐IR spectra indicated that BDE25, BDE47 and BDE154 induced the α‐helix percentage of HEWL decreased from 32.70% ± 1.64% to 28.27% ± 1.41%, 27.50% ± 1.38% and 29.78% ± 1.49%, respectively, whereas the percentage of random coil increased from 26.67% ± 1.33% to 27.60% ± 1.38%, 29.18% ± 1.46% and 30.59% ± 1.53%, respectively. 相似文献
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Ran Zuo Aline de Oliveira Enrica Bullita Maria Ines Torino Kaylie A. Padgett-Pagliai Christopher L. Gardner Natalie A. Harrison Danilo da Silva Marcelo L. Merli Claudio F. Gonzalez Graciela L. Lorca 《Environmental microbiology》2019,21(12):4822-4835
Liberibacter asiaticus is the prevalent causative pathogen of Huanglongbing or citrus greening disease, which has resulted in a devastating crisis in the citrus industry. A thorough understanding of this pathogen's physiology and mechanisms to control cell survival is critical in the identification of therapeutic targets. YbeY is a highly conserved bacterial RNase that has been implicated in multiple roles. In this study, we evaluated the biochemical characteristics of the L. asiaticus YbeY (CLIBASIA_01560) and assessed its potential as a target for antimicrobials. YbeYLas was characterized as an endoribonuclease with activity on 3′ and 5′ termini of 16S and 23S rRNAs, and the capacity to suppress the E. coli ΔybeY phenotype. We predicted the YbeYLas protein:ligand interface and subsequently identified a flavone compound, luteolin, as a selective inhibitor. Site-directed mutagenesis was subsequently used to identify key residues involved in the catalytic activity of YbeYLas. Further evaluation of naturally occurring flavonoids in citrus trees indicated that both flavones and flavonols had potent inhibitory effects on YbeYLas. Luteolin was subsequently examined for efficacy against L. asiaticus in Huanglongbing-infected citrus trees, where a significant reduction in L. asiaticus gene expression was observed. 相似文献