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41.
Shiveta Sharma Shailendra Sharma Ramesh K. Singh Akhauri Vaishampayan 《World journal of microbiology & biotechnology》2008,24(7):1169-1175
Colonization behavior of endophytic bacteria Burkholderia cepacia strains RRE-3 and RRE-5 was studied in the seedlings of rice variety NDR97 using confocal laser scanning microscopy under
controlled laboratory and greenhouse conditions. For studying colonization pattern, bacterial strains were tagged with pHRGFPGUS
plasmid. The role of bacterial strains (both gfp/gus-tagged and untagged) in growth promotion was also studied. After coming into contact with the host root system the bacteria
showed an irregular spreading. Dense colonization was observed on the primary and secondary roots and also on the junction
of emergence of the lateral roots. Results showed that the colonization pattern of Burkholderia cepacia strains was similar to that of other endophytic bacteria isolated from non-legumes. Burkholderia cepacia got entry inside the root at the sites of emergence of lateral roots, without formation of infection threads as in the case
of symbiotic rhizobacteria. Observations suggested that the endophytic bacterial strains RRE-3 and RRE-5 entered inside the
rice roots in a progressive manner. Bacteria were found to line up along the intercellular spaces of adjoining epidermal cells
adjacent to the lateral root junction, indicating endophytic colonization pattern of Burkholderia cepacia strains. Experiments with the rice seedlings inoculated with RRE-3 and RRE-5 strains revealed that both strains enhanced
plant growth considerably when observed under laboratory and greenhouse conditions and produced significantly higher plant
biomass. No considerable difference was observed between the gfp/gus-tagged and non-gfp/gus-tagged strains in the plant growth experiments both in the laboratory and greenhouse conditions. 相似文献
42.
Shailendra P. Singh Manfred Klisch Donat-P. Häder Rajeshwar P. Sinha 《World journal of microbiology & biotechnology》2008,24(12):3111-3115
The induction of shinorine (mycosporine-like amino acid (MAA)) in Anabaena variabilis PCC 7937 was studied in various culture media (BGA−, BGA+, BG11 and Allen and Arnon’s). The objective was to select the most appropriate medium that can support the highest induction
of MAAs and can be used for industrial production of these UV protective substances from cyanobacteria. Also, in vivo photosynthetic
activity was measured under shinorine inducing conditions in all media. The shinorine content and photosynthetic activity
(yield) were highest (2948.73 ± 61.13 nmol/g dry wt and 0.47 ± 0.01, respectively) in BG11 medium in comparison to others
after 72 h of UV radiation. After the same duration of irradiation shinorine content was 1076.08 ± 21.77, 1320.07 ± 98.19
and 554.64 ± 16.47 nmol/g dry wt in BGA−, BGA+, and Allen and Arnon’s media, respectively. Thus, BG11 medium can be used for mass production of MAAs from cyanobacteria. 相似文献
43.
Purpose Fenretinide, 4-(N-hydroxyphenyl) retinamide, (4-HPR) is a well tolerated analog of alltrans retinoic acid. The gangliosideGM3, is a non-specific
inhibitor of EGF receptor autophosphorylation (EGFR-phos). Both compounds were found preferentially cytotoxic to malignant
and proliferating cells when compared to non-proliferating normal brain cells. Some of the small molecule inhibitors of EGFR-phos
are also known to inhibit growth of brain tumors at relatively non-toxic doses. The purpose of this investigation was to evaluate
if 4-HPR and inhibitors of EGFR-phos could be used together in the treatment of brain tumors. Methods The 9L rat gliosarcoma cells were treated in vitro with 4-HPR either alone or in combination with the non-specific or specific
inhibitors of EGFR-phos, GM3 or AG-1478, respectively. The relative viability of the control and treated cells was determined
using 3-(4,5-imethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The experimental data were analyzed for statistical
significance. Results In contrast to the expected additive/synergistic effect on cell growth inhibition, the sub-toxic and toxic concentrations
of 4-HPR protected GM3 treated cells. The viable cells were 3.86 times higher following GM3 plus 4-HPR treatments compared
to GM3 treatment alone. Additionally, a specific inhibitor of EGFR-phos signaling, AG-1478 caused a concentration dependent
protection of cells from the toxicity of 4-HPR. Our results show counteracting cytotoxic responses of 4-HPR and EGFR-phos
inhibitors when used together in 9L rat gliosarcoma cells. 相似文献
44.
Thangaraj K Chaubey G Kivisild T Selvi Rani D Singh VK Ismail T Carvalho-Silva D Metspalu M Bhaskar LV Reddy AG Chandra S Pande V Prathap Naidu B Adarsh N Verma A Jyothi IA Mallick CB Shrivastava N Devasena R Kumari B Singh AK Dwivedi SK Singh S Rao G Gupta P Sonvane V Kumari K Basha A Bhargavi KR Lalremruata A Gupta AK Kaur G Reddy KK Rao AP Villems R Tyler-Smith C Singh L 《Human heredity》2008,66(1):1-9
We have analyzed 7,137 samples from 125 different caste, tribal and religious groups of India and 99 samples from three populations of Nepal for the length variation in the COII/tRNA(Lys) region of mtDNA. Samples showing length variation were subjected to detailed phylogenetic analysis based on HVS-I and informative coding region sequence variation. The overall frequencies of the 9-bp deletion and insertion variants in South Asia were 1.9 and 0.6%, respectively. We have also defined a novel deep-rooting haplogroup M43 and identified the rare haplogroup H14 in Indian populations carrying the 9-bp deletion by complete mtDNA sequencing. Moreover, we redefined haplogroup M6 and dissected it into two well-defined subclades. The presence of haplogroups F1 and B5a in Uttar Pradesh suggests minor maternal contribution from Southeast Asia to Northern India. The occurrence of haplogroup F1 in the Nepalese sample implies that Nepal might have served as a bridge for the flow of eastern lineages to India. The presence of R6 in the Nepalese, on the other hand, suggests that the gene flow between India and Nepal has been reciprocal. 相似文献
45.
正Dear Editor,Zika virus(ZIKV),a pathogen within the genus Flavivirus,family Flaviviridae brought an international public health emergency due to its association with neonatal microcephaly case(Platt and Miner 2017).Currently the most reliable diagnostic test is PCR detection of ZIKV RNA from body fluid samples.Unfortunately,the short viremia window and asymptomatic/mild infections greatly reduce the success rate of PCRs(de Vasconcelos et al.2018). 相似文献
46.
Florian S. Dreyer Martina Cantone Martin Eberhardt Tanushree Jaitly Lisa Walter Jürgen Wittmann Shailendra K. Gupta Faiz M. Khan Olaf Wolkenhauer Brigitte M. Pützer Hans-Martin Jäck Lucie Heinzerling Julio Vera 《生物化学与生物物理学报:疾病的分子基础》2018,1864(6):2315-2328
Cellular phenotypes are established and controlled by complex and precisely orchestrated molecular networks. In cancer, mutations and dysregulations of multiple molecular factors perturb the regulation of these networks and lead to malignant transformation. High-throughput technologies are a valuable source of information to establish the complex molecular relationships behind the emergence of malignancy, but full exploitation of this massive amount of data requires bioinformatics tools that rely on network-based analyses.In this report we present the Virtual Melanoma Cell, an online tool developed to facilitate the mining and interpretation of high-throughput data on melanoma by biomedical researches. The platform is based on a comprehensive, manually generated and expert-validated regulatory map composed of signaling pathways important in malignant melanoma. The Virtual Melanoma Cell is a tool designed to accept, visualize and analyze user-generated datasets. It is available at: https://www.vcells.net/melanoma. To illustrate the utilization of the web platform and the regulatory map, we have analyzed a large publicly available dataset accounting for anti-PD1 immunotherapy treatment of malignant melanoma patients. 相似文献
47.
Archana Singh N. P. Singh S. N. Gurha A. N. Asthana 《Journal of plant biochemistry and biotechnology.》1999,8(2):117-119
Callus cultures established on MS medium containing 2.0 mg l-1 2, 4-D were inoculated on the regeneration medium supplemented with different concentrations (0.5, 1.0, 1.5, 2.0, 2.5 and 3%, v/v) of culture filtrate (CF) of Ascochyta rabiei infesting chickpea. Out of 486 callus pieces and 270 regenerants obtained from immature embryo derived callus screened, 50 callus lines and 74 regenerants were found resistant. Further, these resistant callus lines and regenerants were subjected to stability test by growing them on a medium containing 3% CF. Seventeen callus lines and 28 regenerants of the selected lines showed normal growth on the selection medium. The regenerated plants were tested in pots under artificial epiphytotic conditions where they showed normal growth behaviour and high degree of resistance. 相似文献
48.
Manoj K. Rai Pooja Asthana Shashi Kant Singh V.S. Jaiswal U. Jaiswal 《Biotechnology advances》2009,27(6):641-679
Encapsulation technology is an exciting and rapidly growing area of biotechnological research. This has drawn tremendous attention in recent years because of its wide use in conservation and delivery of tissue cultured plants of commercial and economic importance. Production of synthetic seeds by encapsulating somatic embryos, shoot buds or any other meristmatic tissue helps in minimizing the cost of micropropagated plantlets for commercialization and final delivery. In most of fruit crops, seed propagation has not been successful because of heterozygosity of seeds, minute seed size, presence of reduced endosperm, low germination rate, and also some are having seedless varieties. Many species have desiccation-sensitive intermediate or recalcitrant seeds and can be stored for only a few weeks or months. Under these circumstances, increasing interest has been shown recently to use encapsulation technology for propagation and conservation. Many fruit plants are studied worldwide for breeding, genetic engineering, propagation, and pharmaceutical purposes. In this context, synthetic seeds would be more applicable in exchange of elite and axenic plant material between laboratories and extension centers due to small bead size and ease in handling. Due to these advantages, interest in using encapsulation technology has continuously been increasing in several fruit plant species. The purpose of this review is to focus upon current information on development of synthetic seeds in several fruit crops. 相似文献
49.
Sharma S Sharma S Kopisch-Obuch FJ Keil T Laubach E Stein N Graner A Jung C 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(7):1321-1330
The root-lesion nematode Pratylenchus neglectus can cause severe losses in barley cultivation. Multiplication rates had been found to vary greatly between different barley accessions. Two winter barley cultivars, Igri and Franka, had been found to differ in their ability to resist this parasite. An existing Igri?×?Franka doubled haploid population was chosen to genetically map resistance genes after artificial inoculation with P. neglectus in the greenhouse and climate chamber. A continuous phenotypic variation was found indicating a quantitative inheritance of P. neglectus resistance. An existing map was enriched by 527 newly developed Diversity Array Technology markers (DArTs). The new genetic linkage map was comprised of 857 molecular markers that cover 1,157?cM on seven linkage groups. Using phenotypic data collected from four different experiments in 3?years, five quantitative trait loci were mapped by composite interval mapping on four (3H, 5H, 6H and 7H) linkage groups. A quantitative trait locus with a large phenotypic effect of 16% and likelihood of odds (LOD) score of 6.35 was mapped on linkage group 3H. The remaining four QTLs were classified as minor or moderate with LOD scores ranging from 2.71 to 3.55 and R 2 values ranging from 8 to 10%. The DNA markers linked to the resistance QTLs should be quite useful for marker-assisted selection in barley breeding because phenotypic selection is limited due to time constraints and labor costs. 相似文献
50.
Kapoor S 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(4):1885; author reply 1886-1885; author reply 1885