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Divya Thomas Satish Sagar Thomas Caffrey Paul M. Grandgenett Prakash Radhakrishnan 《Journal of cellular and molecular medicine》2019,23(10):6885-6896
Aberrant expression of Sialyl‐Tn (STn) antigen correlates with poor prognosis and reduced patient survival. We demonstrated that expression of Tn and STn in pancreatic ductal adenocarcinoma (PDAC) is due to hypermethylation of Co re 1 s ynthase specific m olecular c haperone (COSMC) and enhanced the malignant properties of PDAC cells with an unknown mechanism. To explore the mechanism, we have genetically deleted COSMC in PDAC cells to express truncated O‐glycans (SimpleCells, SC) which enhanced cell migration and invasion. Since epithelial‐to‐mesenchymal transition (EMT) play a vital role in metastasis, we have analysed the induction of EMT in SC cells. Expressions of the mesenchymal markers were significantly high in SC cells as compared to WT cells. Equally, we found reduced expressions of the epithelial markers in SC cells. Re‐expression of COSMC in SC cells reversed the induction of EMT. In addition to this, we also observed an increased cancer stem cell population in SC cells. Furthermore, orthotopic implantation of T3M4 SC cells into athymic nude mice resulted in significantly larger tumours and reduced animal survival. Altogether, these results suggest that aberrant expression of truncated O‐glycans in PDAC cells enhances the tumour aggressiveness through the induction of EMT and stemness properties. 相似文献
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Satyajeet Das Sagar Batra Pramodkumar P. Gupta Mukesh Kumar Vijay Kumar Srivastava Anupam Jyoti Nagendra Singh Sanket Kaushik 《Journal of molecular recognition : JMR》2019,32(11)
Enterococcus faecalis is a gram‐positive, rod‐shape bacteria responsible for around 65% to 80% of all enterococcal nosocomial infections. It is multidrug resistant (MDR) bacterium resistant to most of the first‐line antibiotics. Due to the emergence of MDR strains, there is an urgent need to find novel targets to develop new antibacterial drugs against E. faecalis. In this regard, we have identified naphthoate synthase (1,4‐dihydroxy‐2‐naphthoyl‐CoA synthase, EC: 4.1.3.36; DHNS) as an anti‐E. faecalis target, as it is an essential enzyme for menaquinone (vitamin K2) synthetic pathway in the bacterium. Thus, inhibiting naphtholate synthase may consequently inhibit the bacteria's growth. In this regard, we report here cloning, expression, purification, and preliminary structural studies of naphthoate synthase along with in silico modeling, molecular dynamic simulation of the model and docking studies of naphthoate synthase with quercetin, a plant alkaloid. Biochemical studies have indicated quercetin, a plant flavonoid as the potential lead compound to inhibit catalytic activity of EfDHNS. Quercetin binding has also been validated by spectrofluorimetric studies in order to confirm the bindings of the ligand compound with EfDHNS at ultralow concentrations. Reported studies may provide a base for structure‐based drug development of antimicrobial compounds against E. faecalis. 相似文献
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Saikat Pal Thor F. Besier Garry E. Gold Michael Fredericson Scott L. Delp Gary S. Beaupre 《Computer methods in biomechanics and biomedical engineering》2019,22(2):206-216
The purpose of this study was to evaluate the effects of variations in quadriceps muscle forces on patellofemoral stress. We created subject-specific finite element models for 21 individuals with chronic patellofemoral pain and 16 pain-free control subjects. We extracted three-dimensional geometries from high resolution magnetic resonance images and registered the geometries to magnetic resonance images from an upright weight bearing squat with the knees flexed at 60°. We estimated quadriceps muscle forces corresponding to 60° knee flexion during a stair climb task from motion analysis and electromyography-driven musculoskeletal modelling. We applied the quadriceps muscle forces to our finite element models and evaluated patellofemoral cartilage stress. We quantified cartilage stress using an energy-based effective stress, a scalar quantity representing the local stress intensity in the tissue. We used probabilistic methods to evaluate the effects of variations in quadriceps muscle forces from five trials of the stair climb task for each subject. Patellofemoral effective stress was most sensitive to variations in forces in the two branches of the vastus medialis muscle. Femur cartilage effective stress was most sensitive to variations in vastus medialis forces in 29/37 (78%) subjects, and patella cartilage effective stress was most sensitive to variations in vastus medialis forces in 21/37 (57%) subjects. Femur cartilage effective stress was more sensitive to variations in vastus medialis longus forces in subjects classified as maltrackers compared to normal tracking subjects (p?=?0.006). This study provides new evidence of the importance of the vastus medialis muscle in the treatment of patellofemoral pain. 相似文献
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Biological Trace Element Research - Vanadium (V) has not been elucidated as an essential mineral in ruminants, though in lower organisms and rat model, its role is well known as insulin—a... 相似文献
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Maninder Kaur Yogesh Vikal Harleen Kaur Lalit Pal Kirandeep Kaur Jasbir Singh Chawla 《Journal of Phytopathology》2019,167(10):591-600
Southern leaf blight (SLB) caused by the fungus Cochliobolus heterostrophus (Drechs.) Drechs. is a major foliar disease of maize worldwide. Our objectives were to identify quantitative trait loci (QTL) for resistance to SLB and flowering traits in recombinant inbred line (RIL) population derived from the cross of inbred lines LM5 (resistant) and CM140 (susceptible). A set of 207 RILs were phenotyped for resistance to SLB at three time intervals for two consecutive years. Four putative QTL for SLB resistance were detected on chromosomes 3, 8 and 9 that accounted for 54% of the total phenotypic variation. Days to silking and anthesis–silking interval (ASI) QTL were located on chromosomes 6, 7 and 9. A comparison of the obtained results with the published SLB resistance QTL studies suggested that the detected bins 9.03/02 and 8.03/8.02 are the hot spots for SLB resistance whereas novel QTL were identified in bins 3.08 and 8.01/8.04. The linked markers are being utilized for marker‐assisted mobilization of QTL conferring resistance to SLB in elite maize backgrounds. Fine mapping of identified QTL will facilitate identification of candidate genes underlying SLB resistance. 相似文献
129.
Saurabh Kumar Agnihotri Balawant Kumar Ankita Jain Anjali Anjali Mahendra Pal Singh Negi Rekha Sachan Madan Lal Brahma Bhatt Raj Kamal Tripathi Monika Sachdev 《Reports of Biochemistry & Molecular Biology》2022,10(4):711
Background:This study correlates the serum levels of sCD95 & TNF-α with a simple cell-based assay to evaluate the capacity of the serum sample to induce apoptosis in Jurkat cells. Interlinking of these parameters can be explored to design a minimum invasive diagnostic strategy for cervical cancer (CC).Methods:Sera samples were assessed to induce apoptosis in Jurkat cells through FACS. Serum levels of sCD95 and TNF-α were measured by ELISA. JNK phosphorylation was evaluated in sera incubated Jurkat cells. Data was scrutinized through statistical analysis.Results:Significantly higher serum levels of sCD95 and lower TNF-α levels were observed in CC patients; their sera samples inhibited induction of apoptosis in Jurkat cells through reduced JNK phosphorylation. Statistical analysis linked these three parameters for the early screening of CC.Conclusion:Distinct sera levels of sCD95 & TNF-α in CC patients showed an anti-apoptotic effect, which can be considered for early detection of CC.Key Words: Apoptosis, sCD95, Jurkat Cells, Tumor Necrosis Factor-alpha, Uterine Cervical Neoplasms 相似文献
130.
Pal SK Nazir A Mukhopadhyay I Saxena DK Chowdhuri DK 《Indian journal of experimental biology》2001,39(12):1207-1213
Use of the Internet in developing countries is now growing faster. Internet has created a new conduit not only for communication but also in the access, sharing and exchange of information among scientists. The Internet is now viewed as the world's biggest library where retrieval of scientific literature and other information resources are possible within seconds. Large volumes of toxicological information resources are available on the Internet. This review outlines some sites that may be of great importance and useful to the toxicologist. 相似文献