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101.
Dr. Lucyna Goniakowska-Witalińska 《Cell and tissue research》1980,210(3):479-484
Summary Single cells of a new type appear scattered among pneumocytes in the pulmonary epithelium. The surfaces of these cells communicate with the air space and display numerous finger-like microvilli. In comparison to pneumocytes, these cells have a more lucid cytoplasm and their apical parts contain large amounts of electron-lucent vesicles and electron-dense granules, which are probably released into the lumen of the lung. These secretory cells exhibit a yellow formaldehyde-induced fluorescence, which suggests that they belong to the class of APUD cells. 相似文献
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The Crabtree effect (inhibition of respiration by glycolysis) is observed in cells with approximately equal glycolytic and respiratory capacities for ATP synthesis. Addition of glucose to aerobic suspensions of glucose-starved cells (Sarcoma 180 ascites tumor cells) causes a burst of respiration and lactate production due to ATP utilization for glucose phosphorylation by hexokinase and phosphofructokinase. This burst of activity is followed by inhibition of both respiration and glycolysis, the former to below the value before glucose addition (Crabtree effect). Both the respiratory rate and the glycolytic flux appear to be regulated by the cytosolic albeit by completely different mechanisms. Respiration is regulated by the free energy of hydrolysis of ATP, such that the rate increases as the decreases and decreases as the increases. The regulatory enzymes of glycolysis are activated by ADP (AMP) and Pi and inhibited by ATP. Thus both respiration and glycolysis increase or decrease as the decreases or increases. The parallel regulation of both ATP-producing pathways by this common metabolite ratio is consistent with the cytoplasmic being an important determinant of homeostatic regulation of cellular energy metabolism. 相似文献
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The EPR absorption properties of the hemes of cytochrome oxidase and their liganded derivatives were examined in oriented multilayers from isolated oxidase, mitochondrial membranes and membrane fragments of a bacterium, Paracoccus denitrificans. The hemes of the oxidase in all the systems investigated were oriented normal to the plane of the multilayers. The directions of the g signals corresponding to the gx and gy axes of the g tensor were found to be different in low-spin ferric heme in fully oxidized oxidase and in half-reduced liganded oxidase. It is suggested that this different orientation of gx and gy in fully oxidized oxidase and half-reduced liganded oxidase arises because the respective EPR signals belong to two different hemes, those of cytochrome a and a3. 相似文献
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Anna Junkiert-Czarnecka Maria Pilarska-Deltow Aneta Bk Marta Heise Anna Latos-Bieleska Jacek Zaremba Alicja Bartoszewska-Kubiak Olga Haus 《Current issues in molecular biology》2022,44(4):1472
Background: Ehlers-Danlos syndrome (EDS) is a common non-inflammatory, congenital connective tissue disorder. Classical type (cEDS) EDS is one of the more common forms, typically caused by mutations in the COL5A1 and COL5A2 genes, though causative mutations in the COL1A1 gene have also been described. Material and methods: The study group included 59 patients of Polish origin, diagnosed with cEDS. The analysis was performed on genomic DNA (gDNA) with NGS technology, using an Illumina sequencer. Thirty-five genes related to connective tissue were investigated. The pathogenicity of the detected variants was assessed by VarSome. Results: The NGS of 35 genes revealed variants within the COL5A1, COL5A2, COL1A1, and COL1A2 genes for 30 of the 59 patients investigated. Our panel detected no sequence variations for the remaining 29 patients. Discussion: Next-generation sequencing, with an appropriate multigene panel, showed great potential to assist in the diagnosis of EDS and other connective tissue disorders. Our data also show that not all causative genes giving rise to cEDS have been elucidated yet. 相似文献
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