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101.
102.
Th‐17 response and antimicrobial peptide expression are uniformly expressed in gastric mucosa of Helicobacter pylori‐infected patients independently of their clinical outcomes 下载免费PDF全文
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Human pluripotent stem cells (hPSCs) have shown the ability to self-organize into different types of neural organoids (e.g., whole brain organoids, cortical spheroids, midbrain organoids etc.) recently. The extrinsic and intrinsic signaling elicited by Wnt pathway, Hippo/Yes-associated protein (YAP) pathway, and extracellular microenvironment plays a critical role in brain tissue morphogenesis. This article highlights recent advances in neural tissue patterning from hPSCs, in particular the role of Wnt pathway and YAP activity in this process. Understanding the Wnt-YAP interactions should provide us the guidance to predict and modulate brain-like tissue structure through the regulation of extracellular microenvironment of hPSCs. 相似文献
105.
Yuasa HJ Hasegawa T Nakamura T Suzuki T 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2007,146(4):461-469
The indoleamine 2,3-dioxygenase (IDO)-like myoglobin (Mb) is a unique type of Mb isolated from the buccal mass of several archgastropod species. Here, we expressed Sulculus diversicolor IDO-like Mb as a GST-fusion protein in bacteria. The visible spectrum of GST-fusion IDO-like Mb shows characteristic α- and β-peaks, indicating that it binds oxygen. To identify residues important in heme and oxygen binding, we constructed site-directed mutants. We initially replaced each of the 7 histidines of S. diversicolor IDO-like Mb with alanine. The spectra of three mutants (H74A, H288A, and H332A) revealed a remarkable loss of absorbance around 414 nm, indicating that they cannot bind heme. His74, His288, and His332 were also replaced by arginine or tyrosine. Neither H332R nor H332Y contains heme, suggesting that His332 is the proximal ligand of IDO-like Mb. In contrast, both H74R and H288Y mutants were isolated in the heme-binding oxy-form. The autoxidation rates of these two mutants showed that they can bind oxygen as stably as wild-type. His74 and His288 might be partially associated with heme-binding, but do not act as the distal ligand. The S. diversicolor IDO-like Mb seems to stably bind oxygen in a different manner from normal myoglobins. 相似文献
106.
Influence of environmental factors on stomatal development 总被引:6,自引:2,他引:6
107.
Degradation of MyoD mediated by the SCF (MAFbx) ubiquitin ligase 总被引:1,自引:0,他引:1
Tintignac LA Lagirand J Batonnet S Sirri V Leibovitch MP Leibovitch SA 《The Journal of biological chemistry》2005,280(4):2847-2856
108.
Brain Cytochrome Oxidase in Alzheimer''s Disease 总被引:5,自引:0,他引:5
Stephen J. Kish Catherine Bergeron Ali Rajput† Slobodan Dozic‡ Frank Mastrogiacomo Li-Jan Chang Julie M. Wilson Linda M. DiStefano Jose N. Nobrega§ 《Journal of neurochemistry》1992,59(2):776-779
A recent demonstration of markedly reduced (-50%) activity of cytochrome oxidase (CO; complex 4), the terminal enzyme of the mitochondrial enzyme transport chain, in platelets of patients with Alzheimer's disease (AD) suggested the possibility of a systemic and etiologically fundamental CO defect in AD. To determine whether a CO deficiency occurs in AD brain, we measured the activity of CO in homogenates of autopsied brain regions of 19 patients with AD and 30 controls matched with respect to age, postmortem time, sex, and, as indices of agonal status, brain pH and lactic acid concentration. Mean CO activity in AD brain was reduced in frontal (-26%: p less than 0.01), temporal (-17%; p less than 0.05), and parietal (-16%; not significant, p = 0.055) cortices. In occipital cortex and putamen, mean CO levels were normal, whereas in hippocampus, CO activity, on average, was nonsignificantly elevated (20%). The reduction of CO activity, which is tightly coupled to neuronal metabolic activity, could be explained by hypofunction of neurons, neuronal or mitochondrial loss, or possibly by a more primary, but region-specific, defect in the enzyme itself. The absence of a CO activity reduction in all of the examined brain areas does not support the notion of a generalized brain CO abnormality. Although the functional significance of a 16-26% cerebral cortical CO deficit in human brain is not known, a deficiency of this key energy-metabolizing enzyme could reduce energy stores and thereby contribute to the brain dysfunction and neurodegenerative processes in AD. 相似文献
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Ravi S Kamath Maruxa Martinez-Campos Peder Zipperlen Andrew G Fraser Julie Ahringer 《Genome biology》2000,2(1):research00