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Studies have been carried out on the glycosphingolipids of human KB cells grown in monolayer and suspension culture, and by synchronization of the latter with a double thymidine (2mM) block. Glycosphingolipids were identified tentatively by thin layer chromatography, gas-liquid chromatography, and combined gas-liquid chromatography and mass spectrometry. The predominant gangliosides in the these cells were AcNeu-Gal-Glc-Cer and AcNeu-Gal-GalNAc-Gal-(AcNeu). Glc-Cer. Theprincipal neutral glycosphingolipids were Glc-Cer, Gal-Glc-Cer, Gal-Gal-Glc-Cer, and GalNAc-Gal-Gal-Glc-Cer. Incubation of KB cells (grown in monolayer and subsequently in suspension culture) for 48 hours with D-[1-14Clgalactose resulted in appreciable incorporation of radioactivity into all of the principal glycosphingolipids of these cells. These experiments confirmed that KB cells are capable of synthesizing their constituent glycosphingolipids. KB cells grown in suspension culture showed A 2- to 3-fold increase inthe concentration of Glc-Cer, Gal-Glc-Cer, GalNAc-Gal-Gal-Glc-Cer, and AcNeu-Gal1NAc-Gal-Gal-Glc-Cer, and AcNeu-Gal-Ga1NAcGal-(AcNeu)-Glc-Cer. Thus, the occurrence of tissue culture-dependent changes in the level of glycosphingolipids is demonstrated. Perhaps messages governing the synthesis of glycosphingolipids are translated earlier in thecell cycle under certain conditions of growth and are affected by cell-cell contact and cell adhesion. 相似文献
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From the yellow flowers of Chrysanthemum indicum, a new flavone glycoside, acacetin 7-O-β-d-galactopyranoside was isolated and its structure established from spectral evidence and synthesis. 相似文献
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Bornali Chakrabarti Hridoy R Bairagya Deepak Kr Mishra Pradip Kumar Chatterjee Bishnu P Mukhopadhyay 《Bioinformation》2013,9(3):126-133
Human matrix metalloproteinase-8 (hMMP-8) plays a important role in the progression of colorectal cancer, metastasis, multiple
sclerosis and rheumetoid arthritis. Extensive MD-simulation of the PDB and solvated structures of hMMP-8 has revealed the
presence of few conserved water molecules around the catalytic and structural zinc (ZnC and ZnS) ions. The coordination of two
conserved water molecules (W and WS) to ZnS and the H-bonding interaction of WS to S151 have indicated the plausible involvement
of that metal ion in the catalytic process. Beside this the coupling of ZnC and ZnS metal ions (ZnC – WH (W1)…..W2 ….H162 - ZnS)
through two conserved hydrophilic centers (occupied by water molecules) may also provide some rational on the recognition of
two zinc ions which were separated by ~13 Å in their X-ray structures. This unique recognition of both the Zn+2 ions in the enzyme
through conserved water molecules may be implemented/ exploited for the design of antiproteolytic agent using water mimic
drug design protocol. 相似文献
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Mahalakshmi Vijayaraghavan Sengupta Prattusha Sumantran V. N. Suganya Natarajan Chatterjee Suvro 《Cell and Tissue Biology》2020,14(6):448-457
Cell and Tissue Biology - Besides disease condition, very few stress stimulants were determined to provoke red blood cell (RBC) adhesion to endothelial cells (EC). However, the possible role of... 相似文献
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Ritam Chatterjee Biswajoy Ghosh Mousumi Mandal Debaleena Nawn Satarupa Banerjee Mousumi Pal Ranjan Rashmi Paul Swarnabindu Banerjee Jyotirmoy Chatterjee 《European journal of cell biology》2021,100(1):151146
Oral sub-mucous fibrosis (OSF) is a pathophysiological state of oral cavity or oropharynx having a high chance of conversion to oral squamous cell carcinoma (OSCC). It involves fibrotic transformation of sub-epithelial matrix along with epithelial abnormalities. The present work aims to unveil the mechanistic domain regarding OSF to OSCC conversion exploring the scenario of hypoxia associated oxidative stress, epithelial-mesenchymal transition (EMT), metastasis and stemness acquisition. The study involves histopathological analysis of the diseased condition along with the exploration of oxidative stress status, assessment of mitochondrial condition, immunohistochemical analysis of HIF-1α, E-cadherin, vimentin, ERK, ALDH-1, CD133, Shh, Gli-1 and survivin expressions in the oral epithelial region together with the quantitative approach towards collagen deposition in the sub-epithelial matrix. Oxidative stress was found to be associated with type-II EMT in case of OSF attributing the development of sub-epithelial fibrosis and type-III EMT in case of OSCC favoring malignancy associated metastasis. Moreover, the acquisition of stemness during OSCC can also be correlated with EMT. Alteration of Shh and Gli-1 expression pattern revealed the mechanistic association of hypoxia with the phenotypic plasticity and disease manifestation in case of OSF as well as OSCC. Shh/ Gli-1 signaling can also be correlated with survivin mediated cytoprotective phenomenon under oxidative stress. Overall, the study established the correlative network of hypoxia associated oxidative stress, EMT and manifestation of oral pre-cancerous and cancerous condition in a holistic approach that may throw rays of hope in the therapeutic domain of the concerned diseases. 相似文献