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961.
Childhood acute lymphoblastic leukaemia (ALL), a malignant transformation of the lymphoblasts, is highly responsive to chemotherapy. However, due to certain inadequacy in detection of minimal residual disease (MRD), relapse is a common phenomenon. To address this question, the present review deals with the induction of an unique O-acetyl derivative of sialic acid on a few disease-associated glycoproteins and glycolipids at the onset of childhood ALL, a finding of our group in the last decade. This information has been successfully utilized for diagnosis and prognosis of the disease. Existing literature is included for comparison. Additionally, cell surface overexpression of 9-O-acetylated sialoglycoproteins and antibodies against them present in patients' sera aid the survival of the malignant lymphoblasts and suggest a multifaceted role played by these molecules. Taken together, monitoring these molecules helps not only in unravelling the biology of this paediatric malignancy but also in personalizing the treatment strategies for the betterment of the patient population. 相似文献
962.
Chatterjee Tanima De Debasmita Chowdhury Subhankar Bhattacharyya Maitree 《Mammalian genome》2020,31(7-8):252-262
Mammalian Genome - Type 2 diabetes mellitus (T2DM) accompanied by hyperlipidemia confers higher risk for diabetes as well as cardiovascular diseases. NF-κB is actively involved in generating... 相似文献
963.
Subir K. Roy Chowdhury Sandeep Raha Mark A. Tarnopolsky 《Free radical research》2013,47(10):1116-1124
The involvement of mitochondrial glycerophosphate dehydrogenase (mGPDH) has previously been established in the production of ROS in prostate cancer cell lines (LNCaP, DU145, PC3 and CL1). The current study demonstrates that the mRNA level of mGPDH in prostate cancer cells is 3.3–8.9-fold higher compared to the normal prostate epithelial cell line, PNT1A. This is consistent with the enzymatic activity and protein level of mGPDH. However, cytochrome c oxidase (COX) activity is 2.9–3.2-fold down-regulated in androgen-independent prostate cancer cell lines. The level of antioxidant enzymes, catalase, MnSOD and CuZnSOD are up-regulated in prostate cancer cell lines. Furthermore, it was observed that the activity of mGPDH is significantly higher in liver tissues from all mice with cancer compared to liver tissues from control mice. These data suggest that the up-regulation of mGPDH, due to a highly glycolytic environment, contributes to the overall increase in ROS generation and may result in the progression of the cancer. 相似文献
964.
S Pal S Chandra S Chowdhury D Sarkar A N Ghosh C D Gupta 《The Journal of biological chemistry》1999,274(46):32771-32777
We have shown that the domain V of bacterial 23 S rRNA could fold denatured proteins to their active state. This segment of 23 S rRNA could further be split into two parts. One part containing mainly the central loop of domain V could bind denatured human carbonic anhydrase I stably. This association could be reversed by adding the other part of domain V. The released enzyme was directed in such a way by the central loop of domain V that it could now fold by itself to active form. This agrees with our earlier observation that proteins fold within the cell posttranslationally, a process that is completed after release of the newly synthesized polypeptide from the ribosome (Chattopadhyay, S., Pal, S., Chandra, S., Sarkar, D., and DasGupta, C. (1999) Biochim. Biophys. Acta 1429, 293-298). 相似文献
965.
966.
Arabinda N. Chowdhury 《Culture, medicine and psychiatry》1996,20(1):41-65
Attempts at defining and classifying Koro have been undertaken by various researchers over at least the last fifty years without any consensus emerging to date. The occurrence of Koro, not only in different parts of the world but also in association with varied morbidities, has of late diluted its primary identity as a culture-bound syndrome. Further, the DSM-IIIR and ICD-10 provisions to include culture-bound syndromes like Koro are open to various diagnostic options. Consideration was given to have it included in DSM-IV One of the fundamental problems inherent in such attempts is the semantic confusion Koro generates in its basic phenomenological analysis. The present paper deals with some of these issues based on a historical analysis of world Koro literature, and with comments on the future research agendum. 相似文献
967.
Bacillus megaterium RB-05 was grown on glucose and on “tossa-daisee” (Corchorus olitorius)-derived jute, and production and composition of extracellular polysaccharide (EPS) were monitored. An EPS yield of 0.065 ± 0.013 and of 0.297 g ± 0.054 g−1 substrate after 72 h was obtained for glucose and jute, respectively. EPS production in the presence of jute paralleled bacterial cellulase activity. High performance liquid chromatography (HPLC), matrix assisted LASER desorption/ionization-time of flight (MALDI-ToF) mass spectroscopy, and fourier transform infrared (FT-IR) spectroscopy demonstrated that the EPS synthesized in jute culture (JC) differed from that synthesized in glucose mineral salts medium (GMSM). While fucose was only a minor constituent (4.9 wt.%) of EPS from GMSM, it a major component (41.9 wt.%) of EPS synthesized in JC. This study establishes jute as an effective fermentation substrate for EPS production by a cellulase-producing bacterium. 相似文献
968.
Allan AC Billinton A Brown SH Chowdhury A Eatherton AJ Fieldhouse C Giblin GM Goldsmith P Hall A Hurst DN Naylor A Rawlings DA Sime M Scoccitti T Theobald PJ 《Bioorganic & medicinal chemistry letters》2011,21(14):4343-4348
We describe the discovery and optimization of a novel series of benzofuran EP1 antagonists, leading to the identification of 26d, a novel nonacidic EP1 antagonist which demonstrated efficacy in preclinical models of chronic inflammatory pain. 相似文献
969.
Moon HE Islam N Ahn BR Chowdhury SS Sohn HS Jung HA Choi JS 《Bioscience, biotechnology, and biochemistry》2011,75(8):1472-1480
The present work investigates protein tyrosine phosphatase 1B (PTP1B) and the α-glucosidase inhibitory activities of two edible brown algae, Ecklonia stolonifera and Eisenia bicyclis, as well as in their isolated phlorotannins. Since the individual extracts and fractions showed significant inhibitory activities, column chromatography was performed to isolate six phlorotannins, phloroglucinol (1), dioxinodehydroeckol (2), eckol (3), phlorofurofucoeckol-A (4), dieckol (5), and 7-phloroeckol (6). Phlorotannins 3-6 were potent and noncompetitive PTP1B inhibitors with IC(50) values ranging from 0.56 to 2.64 μM; 4-6 exhibited the most potent α-glucosidase inhibition with IC(50) values ranging from 1.37 to 6.13 μM. Interestingly, 4 and 6 were noncompetitive, while 5 exhibited competitive inhibition in an α-glucosidase assay. E. stolonifera and E. bicyclis as well as their isolated phlorotannins therefore possessed marked PTP1B and α-glucosidase inhibitory activities; this could lead to opportunities in the development of therapeutic agents to control the postprandial blood glucose level and thereby prevent diabetic complications. 相似文献
970.
Claire C. Treat Susan M. Natali Jessica Ernakovich Colleen M. Iversen Massimo Lupascu Anthony David McGuire Richard J. Norby Taniya Roy Chowdhury Andreas Richter Hana Šantrůčková Christina Schädel Edward A. G. Schuur Victoria L. Sloan Merritt R. Turetsky Mark P. Waldrop 《Global Change Biology》2015,21(7):2787-2803
Permafrost thaw can alter the soil environment through changes in soil moisture, frequently resulting in soil saturation, a shift to anaerobic decomposition, and changes in the plant community. These changes, along with thawing of previously frozen organic material, can alter the form and magnitude of greenhouse gas production from permafrost ecosystems. We synthesized existing methane (CH4) and carbon dioxide (CO2) production measurements from anaerobic incubations of boreal and tundra soils from the geographic permafrost region to evaluate large‐scale controls of anaerobic CO2 and CH4 production and compare the relative importance of landscape‐level factors (e.g., vegetation type and landscape position), soil properties (e.g., pH, depth, and soil type), and soil environmental conditions (e.g., temperature and relative water table position). We found fivefold higher maximum CH4 production per gram soil carbon from organic soils than mineral soils. Maximum CH4 production from soils in the active layer (ground that thaws and refreezes annually) was nearly four times that of permafrost per gram soil carbon, and CH4 production per gram soil carbon was two times greater from sites without permafrost than sites with permafrost. Maximum CH4 and median anaerobic CO2 production decreased with depth, while CO2:CH4 production increased with depth. Maximum CH4 production was highest in soils with herbaceous vegetation and soils that were either consistently or periodically inundated. This synthesis identifies the need to consider biome, landscape position, and vascular/moss vegetation types when modeling CH4 production in permafrost ecosystems and suggests the need for longer‐term anaerobic incubations to fully capture CH4 dynamics. Our results demonstrate that as climate warms in arctic and boreal regions, rates of anaerobic CO2 and CH4 production will increase, not only as a result of increased temperature, but also from shifts in vegetation and increased ground saturation that will accompany permafrost thaw. 相似文献