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81.
Kumar V Mudgal MM Rani N Jha A Jaggi M Singh AT Sanna VK Singh P Sharma PK Irchhaiya R Burman AC 《Journal of enzyme inhibition and medicinal chemistry》2009,24(3):763-770
A new series of functionalized amino acid derivatives N-substituted 1-N-(tert-butoxycarbonyl)-2,2-dimethyl-4-phenyl-5-oxazolidine carboxamide (1-17) and 1-N-substituted-3-amino-2-hydroxy-3-phenylpropane-1-carboxamide (18-34) were synthesized and evaluated for their in vitro cytotoxicity against human cancer cell lines. Compound 6 has shown interesting cytotoxicity (IC(50) = 5.67 microm) in ovarian cancer, while compound 10 exhibited promising cytotoxicity in ovarian (IC(50) = 6.1 microm) and oral (IC(50) = 4.17 microm) cancers. These compounds could be of use in designing new anti-cancer agents. 相似文献
82.
Nagarani Thotakura Mukesh Dadarwal Pramod Kumar Gajanand Sharma Santosh Kumar Guru Shashi Bhushan Kaisar Raza Om Prakash Katare 《AAPS PharmSciTech》2017,18(3):759-768
Chitosan is a widely employed polysaccharide with positive zeta-potential and better tissue/cell adhesion. Its hydrophilicity, high viscosity, and insolubility at physiological pH are major hurdles in proper utilization of this macromolecule. Therefore, it was conjugated with biocompatible stearic acid and the conjugate was employed to develop polymeric micelles for delivery of tamoxifen to breast cancer cells. The conjugate was characterized by FT-IR and NMR, and the nanocarrier was characterized for micromeritics, surface charge, drug loading, and morphological attributes. The efficacy was evaluated by in vitro MTT studies, safety by erythrocyte compatibility, and biodistribution by in vivo pharmacokinetic studies. Despite better drug loading and sustained drug release, cytotoxicity on MCF-7 breast cancer cells was substantially enhanced and the pharmacokinetic profile was significantly modified. The AUC was enhanced manifolds along with reduced clearance. The findings are unique and provide an alternative to the conventional lipid-based nanocarriers for better dose delivery, tissue adhesion, and desired pharmacokinetic modulation. 相似文献
83.
Paras Sehgal Samatha Mathew Ambily Sivadas Arjun Ray Jyoti Tanwar Sushma Vishwakarma Gyan Ranjan K V Shamsudheen Rahul C Bhoyar Abhishek Pateria Elvin Leonard Mukesh Lalwani Archana Vats Rajeev R Pappuru Mudit Tyagi Saumya Jakati Shantanu Sengupta Binukumar B K Subhabrata Chakrabarti Inderjeet Kaur Rajender K Motiani Vinod Scaria Sridhar Sivasubbu 《The EMBO journal》2021,40(15)
Long non‐coding RNAs (lncRNAs) are emerging as key regulators of endothelial cell function. Here, we investigated the role of a novel vascular endothelial‐associated lncRNA (VEAL2) in regulating endothelial permeability. Precise editing of veal2 loci in zebrafish (veal2 gib005Δ8/+) induced cranial hemorrhage. In vitro and in vivo studies revealed that veal2 competes with diacylglycerol for interaction with protein kinase C beta‐b (Prkcbb) and regulates its kinase activity. Using PRKCB2 as bait, we identified functional ortholog of veal2 in humans from HUVECs and named it as VEAL2. Overexpression and knockdown of VEAL2 affected tubulogenesis and permeability in HUVECs. VEAL2 was differentially expressed in choroid tissue in eye and blood from patients with diabetic retinopathy, a disease where PRKCB2 is known to be hyperactivated. Further, VEAL2 could rescue the effects of PRKCB2‐mediated turnover of endothelial junctional proteins thus reducing hyperpermeability in hyperglycemic HUVEC model of diabetic retinopathy. Based on evidence from zebrafish and hyperglycemic HUVEC models and diabetic retinopathy patients, we report a hitherto unknown VEAL2 lncRNA‐mediated regulation of PRKCB2, for modulating junctional dynamics and maintenance of endothelial permeability. 相似文献
84.
Shubhra Singh Rajeev Kumar Srivastava Mukesh Srivastava S.K. Puri K. Srivastava 《Experimental parasitology》2011,(1):318-321
Studies were carried out to establish the potential of RPNI medium for drug-sensitivity studies using the MSF assay. The drug sensitivity of standard anti-malarials was compared using both the (3H) Hypoxanthine incorporation assay and the MSF assay. The media supplements used during the study have been human serum, FBS and ALBUMAX-II. Drug sensitivity of two parasite lines, adapted to grow separately in conventional as well as in RPNI medium was compared to observe the effect of RPNI medium on functional characteristics of the parasite. The results revealed identical IC50 values of standard anti-malarials obtained by both the (3H) Hypoxanthine incorporation assay and the MSF assay and no untoward effect of FBS and ALBUMAX-II could be noticed on the chemo-sensitivity of standard anti-malarials. Apart from this the chemo-sensitive response of parasite line adapted to grow in RPNI medium was observed to be intact. These findings showed that RPNI medium has potential to be used for chemo-sensitivity studies and the MSF assay being more convenient was observed to be most suitable assay for bio evaluation of new molecules. 相似文献
85.
Verma M Kaur J Kumar M Kumari K Saxena A Anand S Nigam A Ravi V Raghuvanshi S Khurana P Tyagi AK Khurana JP Lal R 《Journal of bacteriology》2011,193(19):5562-5563
Amycolatopsis mediterranei S699 is an actinomycete that produces an important antibiotic, rifamycin B. Semisynthetic derivatives of rifamycin B are used for the treatment of tuberculosis, leprosy, and AIDS-related mycobacterial infections. Here, we report the complete genome sequence (10.2 Mb) of A. mediterranei S699, with 9,575 predicted coding sequences. 相似文献
86.
87.
Sikander Pal Choudhary Renu Bhardwaj B. D. Gupta Prabhu Dutt R. K. Gupta Mukesh Kanwar Stefania Biondi 《Acta Physiologiae Plantarum》2011,33(4):1319-1333
The present investigation recorded significant restoration of seedling growth (root length, shoot length and fresh weight)
upon application of 24-epibrassinolide (EBL) and putrescine (Put) to 7-day-old seedlings of Raphanus sativus L. cv. Pusa chetki grown under copper (Cu) ion stress. EBL and Put with/or without Cu ion treated seedlings showed increased
titers of ascorbic acid, total phenols and proline when compared with Cu-stressed seedlings. Differential responses in the
activities of guaiacol peroxidase (GPOX) and catalase (CAT) were noted for EBL and Put alone or with/or without Cu ion treatment.
Decreased activities of glutathione reductase (GR) and superoxide dismutase (SOD) noted for EBL and Put alone were observed
to enhance significantly when applied in combination with Cu ion solution. A remarkable decrease in malondialdehyde contents
was observed in seedlings treated with EBL and Put alone and with/or without Cu ion stress. Enhanced free radical scavenging
activities were also recorded for seedlings given EBL and Put alone or in combination over Cu ion stressed seedlings. Maximum
DPPH activity was observed in seedlings treated with Put and EBL 10−9 M + Put. Significant enhancements in deoxyribose and reducing power activities were too recorded for Put, EBL and Put + 10−9 M EBL treatments. Improved seedling growth, antioxidant levels (ascorbic acid, total phenols and proline) and enzymic (GPOX,
CAT, SOD and GR) activities and free radical scavenging capacities along with reduced membrane damage in seedlings given EBL
and Put with/or without Cu stress suggests significant and positive interactions of EBL and Put in alleviating the Cu ion
induced oxidative damage in radish seedlings. 相似文献
88.
89.
Background and Aims
Cytokinins are a major group of plant hormones and are associated with various developmental processes. Developing caryopses of maize have high levels of cytokinins, but little is known about their spatial and temporal distribution. The localization and quantification of cytokinins was investigated in maize (Zea mays) caryopsis from 0 to 28 d after pollination together with the expression and localization of isopentenyltransferase ZmIPT1 involved in cytokinin biosynthesis and ZmCNGT, the gene putatively involved in N9-glucosylation.Methods
Biochemical, cellular and molecular approaches resolved the overall cytokinin profiles, and several gene expression assays were used for two critical genes to assess cytokinin cell-specific biosynthesis and conversion to the biologically inactive form. Cytokinins were immunolocalized for the first time in maize caryopses.Key Results
During the period 0–28 d after pollination (DAP): (1) large quantities of cytokinins were detected in the maternal pedicel region relative to the filial tissues during the early stages after fertilization; (2) unpollinated ovules did not accumulate cytokinins; (3) the maternal nucellar region showed little or no cytokinin signal; (4) the highest cytokinin concentrations in filial endosperm and embryo were detected at 12 DAP, predominantly zeatin riboside and zeatin-9-glucoside, respectively; and (5) a strong cytokinin immuno-signal was detected in specific cell types in the pedicel, endosperm and embryo.Conclusions
The cytokinins of developing maize caryopsis may originate from both local syntheses as well as by transport. High levels of fertilization-dependent cytokinins in the pedicel suggest filial control on metabolism in the maternal tissue; they may also trigger developmental programmed cell death in the pedicel. 相似文献90.