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911.
Chronic Administration of Mood Stabilizers Upregulates BDNF and Bcl-2 Expression Levels in Rat Frontal Cortex 总被引:1,自引:0,他引:1
Brain-derived neurotrophic factor (BDNF) and B-cell lymphoma-2 (Bcl-2) proteins are neuroprotective factors involved in neuronal
signaling, survival and plasticity. Both can be regulated by cyclic AMP response element binding (CREB) protein. Decreased
levels of BDNF and Bcl-2 are implicated in the pathogenesis of bipolar disorder. The present study investigated whether chronically
administered mood stabilizers would increase BDNF and/or Bcl-2 levels in rat brain. Real time RT-PCR, sandwich ELISA and Western
blotting were used to measure BDNF and Bcl-2 mRNA and protein levels in the frontal cortex of rats chronically administered
carbamazepine (CBZ) or lamotrigine (LTG) to produce plasma concentrations therapeutically relevant to bipolar disorder. Chronic
CBZ and LTG significantly increased BDNF and Bcl-2 mRNA and protein levels in the frontal cortex. A common mechanism of action
of mood stabilizers in the treatment of bipolar disorder may involve neuroprotection mediated by upregulation of brain BDNF
and Bcl-2 expression. 相似文献
912.
Liqian Sun Manman Zhao Aihua Liu Ming Lv Jingbo Zhang Youxiang Li Xinjian Yang Zhongxue Wu 《Cellular and molecular neurobiology》2018,38(2):541-548
Phenotypic modulation of vascular smooth muscle cells (VSMCs) is involved in the pathophysiological processes of the intracranial aneurysms (IAs). Although shear stress has been implicated in the proliferation, migration, and phenotypic conversion of VSMCs, the molecular mechanisms underlying these events are currently unknown. In this study, we investigated whether shear stress(SS)-induced VSMC phenotypic modulation was mediated by autophagy involved in adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR)/Unc-51-like kinase 1 (ULK1) pathway. The results show that shear stress could inhibit the expression of key VSMC contractile genes and induce pro-inflammatory/matrix-remodeling genes levels, contributing to VSMCs phenotypic switching from a contractile to a synthetic phenotype. More importantly, Shear stress also markedly increased the levels of the autophagy marker microtubule-associated protein light chain 3-II (LC3II), Beclin-1, and p62 degradation. The autophagy inhibitor 3-methyladenine (3-MA) significantly blocked shear-induced phenotypic modulation of VSMCs. To further explore the molecular mechanism involved in shear-induced autophagy, we found that shear stress could activate AMPK/mTOR/ULK1 signaling pathway in VSMCs. Compound C, a pharmacological inhibitor of AMPK, significantly reduced the levels of p-AMPK and p-ULK, enhanced p-mTOR level, and finally decreased LC3II and Beclin-1 level, which suggested that activated AMPK/mTOR/ULK1 signaling was related to shear-mediated autophagy. These results indicate that shear stress promotes VSMC phenotypic modulation through the induction of autophagy involved in activating the AMPK/mTOR/ULK1 pathway. 相似文献
913.
Han Hu Kshitij Khatri Joshua Klein Nancy Leymarie Joseph Zaia 《Glycoconjugate journal》2016,33(3):285-296
Despite the publication of several software tools for analysis of glycopeptide tandem mass spectra, there remains a lack of consensus regarding the most effective and appropriate methods. In part, this reflects problems with applying standard methods for proteomics database searching and false discovery rate calculation. While the analysis of small post-translational modifications (PTMs) may be regarded as an extension of proteomics database searching, glycosylation requires specialized approaches. This is because glycans are large and heterogeneous by nature, causing glycopeptides to exist as multiple glycosylated variants. Thus, the mass of the peptide cannot be calculated directly from that of the intact glycopeptide. In addition, the chemical nature of the glycan strongly influences product ion patterns observed for glycopeptides. As a result, glycopeptidomics requires specialized bioinformatics methods. We summarize the recent progress towards a consensus for effective glycopeptide tandem mass spectrometric analysis. 相似文献
914.
Silin Wu Ye Gu Yuying Huang Tyh-Chai Wong Hailin Ding Tengfei Liu Yu Zhang Xiaobiao Zhang 《Biochemical genetics》2017,55(3):253-267
The microRNAs (miRNAs) are involved in multiple pathological processes among various types of tumors. However, the functions of miRNAs in benign brain tumors are largely unexplored. In order to explore the pathogenesis of the invasiveness in non-functional pituitary adenoma (NFPA), the miRNAs expression profile was analyzed between invasive and non-invasive non-functional pituitary adenoma by miRNAs microarray. Six most significant differentially expressed miRNAs were identified including four upregulated miRNAs hsa-miR-181b-5p, hsa-miR-181d, hsa-miR-191-3p, and hsa-miR-598 and two downregulated miRNAs hsa-miR-3676-5p and hsa-miR-383. The functions and corresponding signaling pathways of differentially expressed miRNAs were investigated by bioinformatics techniques, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The result of GO analysis indicates regulation of voltage-gated potassium channel activity, positive regulation of sodium ion transport, positive regulation of GTPase activity, negative regulation of Notch signaling pathway, etc. KEGG pathway reveals a series of biological processes, including prolactin signaling pathway, endocrine and other factor-regulated calcium reabsorption, fatty acid metabolism, neuroactive ligand-receptor interaction, etc. The miRNAs hsa-miR-181a-5p was verified by quantitative real-time PCR, and the expression level was in accordance with the microarray result. Our result can provide the evidence on featured miRNAs which play a prominent role in pituitary adenoma as effective biomarkers and therapeutic targets in the future. 相似文献
915.
The localized surface plasmon resonances of multilayered nanostructures are studied using finite difference time domain simulations and plasmon hybridization method. Concentric metal–dielectric–metal (MDM) structure with metal core and nanoshell separated by a thin dielectric layer exhibits a strong coupling between the core and nanoshell plasmon resonance modes. The coupled resonance mode wavelengths show dependence on the dielectric layer thickness and composition of core and outer layer metal. The aluminum-based MDM structures show lower plasmon wavelength compared with Ag- and Au-based MDM nanostructures. The calculated refractive index sensitivity (RIS) factor is in the order Ag–Air–Ag>Au–Air–Au>Al–Air–Al for monometallic multilayered nanostructures. Bimetallic multilayered nanostructures support strong and tunable plasmon resonance wavelengths as well as high RIS factor of 510 nm/refractive index unit (RIU) and 470 nm/RIU for Al–Air–Au and Ag-Air-Au, respectively. The MDM structures not only exhibit higher index sensitivity but also cover a wide ultraviolet–near-infrared wavelengths, making these structures very promising for index sensing, biomolecule sensing, and surface-enhanced Raman spectroscopy. 相似文献
916.
Benjamin L. VaughanJr. Bryan G. Smith David L. Chopp 《Bulletin of mathematical biology》2010,72(5):1143-1165
In this paper, we study quorum sensing in Pseudomonas aeruginosa biofilms. Quorum sensing is a process where bacteria monitor their population density through the release of extra-cellular
signalling molecules. The presence of these molecules affects gene modulation leading to changes in behaviour such as the
release of virulence factors. Here, we use numerical methods to approximate a 2-D model of quorum sensing. It is observed
that the shape of the biofilm can have a profound effect on the onset of quorum sensing. This has serious repercussions for
experimental observations since biofilms of the same biomass but different shapes can produce quite different results. 相似文献
917.
918.
Hawon Lee Dae Haeng Cho Yong Hwan Kim Soo-Jeong Shin Sung Bong Kim Sung Ok Han Jinwon Lee Seung Wook Kim Chulhwan Park 《Biotechnology and Bioprocess Engineering》2011,16(4):755-760
The hydrolysis which converts polysaccharides to the fermentable sugars for yeast’s lingocellulosic ethanol production also
generates byproducts which inhibit the ethanol production. To investigate the extent to which inhibitory compounds affect
yeast’s growth and ethanol production, fermentations by Saccharomyces cerevisiae K35 were investigated in various concentrations of acetic acid, furfural, 5-hydroxymethylfurfural (5-HMF), syringaldehyde,
and coumaric acid. Fermentation in hydrolysates from yellow poplar and waste wood was also studied. After 24 h, S. cerevisiae K35 produced close to theoretically predicted ethanol yields in all the concentrations of acetic acid tested (1 ∼ 10 g/L).
Both furans and phenolics inhibited cell growth and ethanol production. Ethanol yield, however, was unaffected, even at high
concentrations, except in the cases of 5 g/L of syringaldehyde and coumaric acid. Although hydrolysates contain various toxic
compounds, in their presence, S. Cerevisiae K35 consumed close to all the available glucose and yielded more ethanol than theoretically predicted. S. Cerevisiae K35 was demonstrated to have high tolerance to inhibitory compounds and not to need any detoxification for ethanol production
from hydrolysates. 相似文献
919.
Cytoskeleton proteins are substrates for proteases and further apoptotic death. We evaluated the participation of cytoskeleton
in morphological changes during cell death induced by two apoptotic conditions, potassium deprivation (K5) and staurosporine,
in cerebellar granule neurons (CGC). We found that K5 induced somatic damage, but neurites were relatively preserved, which
corresponded to the reorganization of actin and α-tubulin in neurites. Staurosporine (STS) induced an early alteration of
neurites with reorganization of cytoskeleton proteins in somas. Caspase inhibitor ZVAD totally inhibited STS-induced α-tubulin
reorganization and partially blocked STS-induced actin reorganization. α-tubulin and actin reorganization induced by K5 was
affected by ZVAD. Calpain inhibitor (IC1) did not affect α-tubulin or actin reorganization induced by STS, K5 or ionomycin.
Neither ZVAD, nor IC1 changed α-tubulin or actin levels upon K5 treatment. STS increased α-tubulin and actin levels, but neither
ZVAD nor IC1 changed α-tubulin levels upon STS treatment. In contrast, ZVAD reduced the STS-induced increase of actin. These
results suggest that CGC cytoskeleton proteins undergo a differential expression and reorganization depending on the apoptotic
condition. 相似文献
920.
Jay G. Forsythe Sloane L. English Rachel E. Simoneaux Arthur L. Weber 《Origins of life and evolution of the biosphere》2018,48(2):201-211
A one-pot method was developed for the preparation of a series of β-alanine standards of moderate size (2 to ≥12 residues) for studies concerning the prebiotic origins of peptides. The one-pot synthesis involved two sequential reactions: (1) dry-down self-condensation of β-alanine methyl ester, yielding β-alanine peptide methyl ester oligomers, and (2) subsequent hydrolysis of β-alanine peptide methyl ester oligomers, producing a series of β-alanine peptide standards. These standards were then spiked into a model prebiotic product mixture to confirm by HPLC the formation of β-alanine peptides under plausible reaction conditions. The simplicity of this approach suggests it can be used to prepare a variety of β-peptide standards for investigating differences between α- and β-peptides in the context of prebiotic chemistry. 相似文献