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61.
Sara L Goodacre Oliver Y Martin Dries Bonte Linda Hutchings Chris Woolley Kamal Ibrahim CF George Thomas Godfrey M Hewitt 《BMC biology》2009,7(1):32-8
Background
Dispersal plays a key role in shaping biological and ecological processes such as the distribution of spatially-structured populations or the pace and scale of invasion. Here we have studied the relationship between long-distance dispersal behaviour of a pest-controlling money spider,Erigone atra, and the distribution of maternally acquired endosymbionts within the wider meta-population. This spider persists in heterogeneous environments because of its ability to recolonise areas through active long-distance airborne dispersal using silk as a sail, in a process termed 'ballooning'. 相似文献62.
Kamal A Reddy MK Ramaiah MJ Rajender Reddy JS Srikanth YV Dastagiri D Bharathi EV Pushpavalli SN Sarma P Pal-Bhadra M 《Bioorganic & medicinal chemistry》2011,19(8):2565-2581
A series of new estradiol linked pyrrolo[2,1-c][1,4]benzodiazepine (E(2)-PBD) conjugates (3a-f, 4a-f and 5a-f) with different linker architectures including a triazole moiety have been designed and synthesized. All the 18 compounds have been evaluated for their anticancer activity and it is observed that some of the compounds particularly 4c-e and 5c,d exhibited significant anticancer activity. The detailed biological aspects relating to the cell cycle effects and tubulin depolymerization activity have been examined with a view to understand the mechanism of action of these conjugates. Among all these conjugates, one of the compound 5c could be considered as the most effective compound particularly against MCF-7 breast cancer cell line. 相似文献
63.
64.
Aim of work: To assess the impact of Cytochrome P450 3A5 (CYP3A5) and multidrug resistance-1 gene (MDR-1) single nucleotide polymorphisms on the dose and blood level of tacrolimus among liver transplanted patients.Patients and methods: We enrolled a prospective study of 41 liver transplanted patients. Dose-adjusted trough blood concentration (C/D ratio) was calculated. Polymerase chain reaction-restriction fragment length polymorphism followed by sequencing was done for genotyping of CYP3A5*3 (6986A?>?G).Results: At 1 week, 1 and 3 months C/D ratio were significantly lower in CYP3A5 expressers *1/*1 patients compared to non-expressers *3/*3.Conclusion: CYP3A5 (6986A?>?G) genotype, rather than MDR-1 (2677G?>?A/T) variant, has an impact on tacrolimus pharmacokinetics. 相似文献
65.
Nageshwar YV Sheelu G Shambhu RR Muluka H Mehdi N Malik MS Kamal A 《Bioprocess and biosystems engineering》2011,34(5):515-523
Microbial nitrilases are biocatalysts of interest and the enzyme produced using various inducers exhibits altered substrate
specificity, which is of great interest in bioprocess development. The aim of the present study is to investigate the nitrilase-producing
Alcaligenes faecalis MTCC 10757 (IICT-A3) for its ability to transform various nitriles in the presence of different inducers after optimization
of various parameters for maximum enzyme production and activity. The production of A. faecalis MTCC 10757 (IICT-A3) nitrilase was optimum with glucose (1.0%), acrylonitrile (0.1%) at pH 7.0. The nitrilase activity of
A. faecalis MTCC 10757 (IICT-A3) was optimum at 35 °C, pH 8.0 and the enzyme was stable up to 6 h at 50 °C. The nitrilase enzyme produced
using different inducers was investigated for substrate specificity. The enzyme hydrolyzed aliphatic, heterocyclic and aromatic
nitriles with different substitutions. Acrylonitrile was the most preferred substrate (~40 U) as well as inducer. Benzonitrile
was hydrolyzed with almost twofold higher relative activity than acrylonitrile when it was used as an inducer. The versatile
nitrilase-producing A. faecalis MTCC 10757 (IICT-A3) exhibits efficient conversion of both aliphatic and aromatic nitriles. The aromatic nitriles, which
show not much or no affinity towards nitrilase from A. faecalis, are hydrolyzed effectively with this nitrilase-producing organism. Studies are in progress to exploit this organism for
synthesis of industrially important compounds. 相似文献
66.
Kamal Fouad Abdellatif Hanaa Mahdy AbouZeid 《Journal of Genetic Engineering and Biotechnology》2011,9(2):157-163
The genetic diversity of 14 bread wheat (Triticum aestivum L.) varieties originating from Mediterranean region (Egypt and Greece) was assessed by means of Randomly Amplified Polymorphic DNA (RAPD) markers. Seventeen RAPD markers were used to analyze and compare genetic diversity among the selected wheat varieties. Average of similarity coefficients based on RAPD markers for all of the studied varieties was 0.718. Average and range of genetic similarity coefficients among varieties obtained from both Egypt and Greece independently were 0.765 (from 0.66 to 0.886) and 0.723 (from 0.604 to 0.896), respectively. The cophenetic correlation coefficients of the three RAPD dendrograms (generated for all of the 14 varieties, the seven Egyptian varieties separately and the seven Greek varieties separately) were r = 0.774, 0.80, and 0.74, respectively. Both cluster analysis and Principal Coordinate Analysis (PCOORDA) were able to differentiate between Egyptian and Greek wheat varieties, but PCOORDA was more efficient in its separation. The percentage of variance accounted for the first two principal coordinates was 49.45% of total genetic variance for RAPD. Notable geographical divergence was found between Egyptian and Greek wheat varieties. 相似文献
67.
Michaely P Kamal A Anderson RG Bennett V 《The Journal of biological chemistry》1999,274(50):35908-35913
Recent studies suggest that the mobility of clathrin-coated pits at the cell surface are restricted by an actin cytoskeleton and that there is an obligate reduction in the amount of spectrin on membranes during coated pit budding. The spectrin-actin cytoskeleton associates with membranes primarily through ankyrins, which interact with the cytoplasmic region of numerous integral membrane proteins. We now report that the fourth repeat domain (D4) of ankyrin(R) binds to the N-terminal domain of clathrin heavy chain with high affinity. Addition of peptides containing the D4 region inhibited clathrin-coated pit budding in vitro. In addition, microinjection of D4 containing peptides blocked the endocytosis of fluorescent low density lipoprotein (LDL). Ankyrin(R) peptides that contained repeat domains other than D4 had no effect on either in vitro budding or internalization of LDL. Finally, immunofluorescence shows that ankyrin is uniformly associated with endosomes that contain fluorescent LDL. These results suggest that ankyrin plays a role in the budding of clathrin-coated pits during endocytosis. 相似文献
68.
The innate immunity of a marine red alga involves oxylipins from both the eicosanoid and octadecanoid pathways 总被引:1,自引:0,他引:1 下载免费PDF全文
The oxygenated derivatives of fatty acids, known as oxylipins, are pivotal signaling molecules in animals and terrestrial plants. In animal systems, eicosanoids regulate cell differentiation, immune responses, and homeostasis. In contrast, terrestrial plants use derivatives of C18 and C16 fatty acids as developmental or defense hormones. Marine algae have emerged early in the evolution of eukaryotes as several distinct phyla, independent from the animal and green-plant lineages. The occurrence of oxylipins of the eicosanoid family is well documented in marine red algae, but their biological roles remain an enigma. Here we address the hypothesis that they are involved with the defense mechanisms of the red alga Chondrus crispus. By investigating its association with a green algal endophyte Acrochaete operculata, which becomes invasive in the diploid generation of this red alga, we showed that (1) when challenged by pathogen extracts, the resistant haploid phase of C. crispus produced both C20 and C18 oxylipins, (2) elicitation with pathogen extracts or methyl jasmonate activated the metabolism of C20 and C18 polyunsaturated fatty acids to generate hydroperoxides and cyclopentenones such as prostaglandins and jasmonates, and (3) C20 and C18 hydroperoxides as well as methyl jasmonate did induce shikimate dehydrogenase and Phe ammonialyase activities in C. crispus and conferred an induced resistance to the diploid phase, while inhibitors of fatty acid oxidation reduced the natural resistance of the haploid generation. The dual nature of oxylipin metabolism in this alga suggests that early eukaryotes featured both animal- (eicosanoids) and plant-like (octadecanoids) oxylipins as essential components of innate immunity mechanisms. 相似文献
69.
C2-Fluoro substituted pyrrolobenzodiazepines (PBDs) have been synthesized that exhibit potential anticancer activity in a number of human tumour cell lines. These C2-fluoro substituted PBDs also exhibit significant DNA-binding ability. 相似文献
70.
Kamal A Ramu R Khanna GB Saxena AK Shanmugavel M Pandita RM 《Bioorganic & medicinal chemistry letters》2004,14(19):4907-4909
New pyrrolobenzodiazepine-anthraquinone hybrids have been designed and synthesized, found to effectively bind to DNA and also exhibit cytotoxicity against many cancer cell lines 相似文献