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991.
Shiwali Sharma Anwar Shahzad Altaf Ahmad Laiqa Anjum 《Acta Physiologiae Plantarum》2014,36(9):2331-2344
The present study reports a high frequency in vitro propagation protocol through apical bud sprouting and basal organogenic nodule formation in shoot tip explants of Decalepis hamiltonii, an endemic and endangered medicinal liana. Among different combinations of plant growth regulators (PGRs) and growth additives, maximum of 8.20 shoots per explant with mean shoot length of 6.54 cm were induced on Murashige and Skoog’s medium (MS) supplemented with 5.0 µM 6-benzyladenine (BA) + 0.5 µM indole-3-acetic acid (IAA) + 30.0 µM adenine sulphate (ADS) through apical bud sprouting. On single cytokinin treatment explants did not exhibit good multiplication but showed nodulation (N1) from the basal cut end similar to cytokinin–auxin combination (N2). Between two types of nodular tissues, N2 was proved to be better for maximum shoot regeneration (15.40 shoots per explant) and shoot length (4.56 cm) when cultured on MS medium supplemented with 5.0 µM BA, 0.5 µM IAA, 30.0 µM ADS and 1.0 µM gibberellic acid (GA3). Microshoots were efficiently rooted on half-strength MS medium supplemented with 2.5 μM α-naphthalene acetic acid (NAA). After successful acclimatization in Soilrite, 95.10 % plantlets were survived in field conditions. Histological investigation proved useful in ascertaining the callogenic nature of the regenerating nodular tissue formed at the basal cut end of shoot tip explant. Acclimatized plantlets were studied for the estimation of chlorophyll and carotenoid content as well as the net photosynthetic rate (PN) during subsequent days of transfer to ex vitro condition. Moreover, acclimatization had a significant effect on biomass production and the synthesis of 2-hydroxy-4-methoxy benzaldehyde (2HMB). Maximum fresh weight (3.78 gm/plant), dry weight (0.39 gm/plant) of roots and 2HMB content (15.94 µg/ml of extract) were noticed after 8 weeks of acclimatization. 相似文献
992.
Gunhild M. Mueller Ahmad B. Maarouf Carol L. Kinlough Nan Sheng Ossama B. Kashlan Sora Okumura Sarah Luthy Thomas R. Kleyman Rebecca P. Hughey 《The Journal of biological chemistry》2010,285(40):30453-30462
The epithelial Na+ channel (ENaC) is comprised of three homologous subunits (α, β, and γ) that have a similar topology with two transmembrane domains, a large extracellular region, and cytoplasmic N and C termini. Although ENaC activity is regulated by a number of factors, palmitoylation of its cytoplasmic Cys residues has not been previously described. Fatty acid-exchange chemistry was used to determine whether channel subunits were Cys-palmitoylated. We observed that only the β and γ subunits were modified by Cys palmitoylation. Analyses of ENaCs with mutant β subunits revealed that Cys-43 and Cys-557 were palmitoylated. Xenopus oocytes expressing ENaC with a β C43A,C557A mutant had significantly reduced amiloride-sensitive whole cell currents, enhanced Na+ self-inhibition, and reduced single channel Po when compared with wild-type ENaC, while membrane trafficking and levels of surface expression were unchanged. Computer modeling of cytoplasmic domains indicated that β Cys-43 is in proximity to the first transmembrane α helix, whereas β Cys-557 is within an amphipathic α-helix contiguous with the second transmembrane domain. We propose that β subunit palmitoylation modulates channel gating by facilitating interactions between cytoplasmic domains and the plasma membrane. 相似文献
993.
Tabassum Niyaz 《Archives Of Phytopathology And Plant Protection》2013,46(9):829-834
Abstract Under greenhouse conditions, the experiment was conducted to test the efficacy of opportunistic and nematophagous hyphomycete, Paecilomyces lilacinus against root-knot nematode, Meloidogyne incognita on Eclipta alba. The treatment comprised inoculation of E. alba with M. incognita alone (N) and in combination with P. lilacinus (one week before (T1), simultaneously (T2), one week after (T3), two weeks after (T4) and three weeks after (T5)). The results showed that the application of P. lilacinus before one week of nematode inoculation (Tl) was more effective than other treatments. A significant enhancement was noticed in the growth and yield of E. alba. Root-knot and egg mass indices were suppressed due to destruction of the mature females and the egg masses. Histopathological studies revealed the presence of P. lilacinus hyphae in and around the females and the eggs. 相似文献
994.
Saeid Ghorbian Ahmad Poursadegh Zonouzi 《Indian journal of human genetics》2013,19(2):273-Jun;19(2):273
995.
Many authors have agreed on the interest of considering environmental concerns in the early stages of product development. However, most eco‐design tools are based on life cycle assessment principles and require a model to give information about the product's environmental performance. This modeling can have negative effects on team performance and on the potential for innovation, not to mention on the project's duration. Additionally, the model requires information that is not available in the early design stages. This article analyzes the potential of inferring conclusions about the life cycle stages with the highest impact by using similar products. From a database of previous products, environmental profile estimations are carried out, that is, the assessments of the contribution of each life cycle stage to the total impact and the variability of this measure. It is then possible to discard—or ensure consideration of—life cycle stages. Furthermore, the level of the conclusions is assessed on a five‐point scale. The proposed approach is applied to four case studies with different levels of abstraction and the relevance of the conclusions is assessed. The article resolves the problems regarding potential for estimating the distribution of the environmental impacts along the life cycle. 相似文献
996.
997.
Ahmad IM Abdalla MY Aykin-Burns N Simons AL Oberley LW Domann FE Spitz DR 《Free radical biology & medicine》2008,44(5):826-834
Overexpression of the tumor suppressor gene, wild-type p53 (wtp53), using adenoviral vectors (Adp53) has been suggested to kill cancer cells by hydroperoxide-mediated oxidative stress [1,2] and nutrient distress induced by the glucose analog, 2-deoxyglucose (2DG), has been suggested to enhance tumor cell killing by agents that induce oxidative stress via disrupting hydroperoxide metabolism [3,4]. In the current study clonogenic cell killing of PC-3 and DU-145 human prostate cancer cells (lacking functional p53) mediated by 4 h exposure to 50 plaque forming units (pfus)/cell of Adp53 (that caused the enforced overexpression of wtp53) was significantly enhanced by treatment with 2DG. Accumulation of glutathione disulfide was found to be significantly greater in both cell lines treated with 2DG+Adp53 and both cell lines treated with 2DG+Adp53 showed a approximately 2-fold increases in dihydroethidine (DHE) and 5-(and-6)-carboxy-2',7'-dichlorodihydrofluorescein diacetate (CDCFH(2)) oxidation, indicative of increased steady-state levels of O(2)(.-) and hydroperoxides, respectively. Finally, overexpression of catalase or glutathione peroxidase using adenoviral vectors partially, but significantly, protected DU-145 cells from the toxicity induced by 2DG+Adp53 treatment. These results show that treatment of human prostate cancer cells with the combination of 2DG (a nutrient stress) and overexpression of the tumor suppressor gene, wtp53, enhances clonogenic cell killing by a mechanism that involves oxidative stress as well as allowing for the speculation that inhibitors of glucose and hydroperoxide metabolism can be used in combination with Adp53 gene therapy to enhance therapeutic responses. 相似文献
998.
Yarbakht Melina Nikkhah Maryam Moshaii Ahmad Abbasian Sara Dellith Andrea 《Plasmonics (Norwell, Mass.)》2018,13(2):715-726
Plasmonics - Although glancing angle deposited silver substrates offer an excellent figures for surface enhanced Raman scattering (SERS) sensing, the chemical instability issues of silver... 相似文献
999.
Sajad Ali Zahoor Ahmad Mir Anshika Tyagi Javaid A. Bhat Narayanappa Chandrashekar Pradeep Kumar Papolu Sandhya Rawat Anita Grover 《Acta Physiologiae Plantarum》2017,39(12):268
Pathogenesis-related proteins (PRs) are the antimicrobial proteins which are commonly used as signatures of defense signaling pathways and systemic acquired resistance. However, in Brassica juncea most of the PR proteins have not been fully characterized and remains largely enigmatic. In this study, full-length cDNA sequences of SA (PR1, PR2, PR5) and JA (PR3, PR12 and PR13) marker genes were isolated from B. juncea and were named as BjPR proteins. BjPR proteins showed maximum identity with known PR proteins of Brassica species. Further, expression profiling of BjPR genes were investigated after hormonal, biotic and abiotic stresses. Pre-treatment with SA and JA stimulators downregulates each other signature genes suggesting an antagonistic relationship between SA and JA in B. juncea. After abscisic acid (ABA) treatment, SA signatures were downregulated while as JA signature genes were upregulated. During Erysiphe cruciferarum infection, SA- and JA-dependent BjPR genes showed distinct expression pattern both locally and systemically, thus suggesting the activation of SA- and JA-dependent signaling pathways. Further, expression of SA marker genes decreases while as JA-responsive genes increases during drought stress. Interestingly, both SA and JA signature genes were induced after salt stress. We also found that BjPR genes displayed ABA-independent gene expression pattern during abiotic stresses thus providing the evidence of SA/JA cross talk. Further, in silico analysis of the upstream regions (1.5 kb) of both SA and JA marker genes showed important cis-regulatory elements related to biotic, abiotic and hormonal stresses. 相似文献
1000.
Moradi AB Carminati A Vetterlein D Vontobel P Lehmann E Weller U Hopmans JW Vogel HJ Oswald SE 《The New phytologist》2011,192(3):653-663
? Despite the importance of rhizosphere properties for water flow from soil to roots, there is limited quantitative information on the distribution of water in the rhizosphere of plants. ? Here, we used neutron tomography to quantify and visualize the water content in the rhizosphere of the plant species chickpea (Cicer arietinum), white lupin (Lupinus albus), and maize (Zea mays) 12 d after planting. ? We clearly observed increasing soil water contents (θ) towards the root surface for all three plant species, as opposed to the usual assumption of decreasing water content. This was true for tap roots and lateral roots of both upper and lower parts of the root system. Furthermore, water gradients around the lower part of the roots were smaller and extended further into bulk soil compared with the upper part, where the gradients in water content were steeper. ? Incorporating the hydraulic conductivity and water retention parameters of the rhizosphere into our model, we could simulate the gradual changes of θ towards the root surface, in agreement with the observations. The modelling result suggests that roots in their rhizosphere may modify the hydraulic properties of soil in a way that improves uptake under dry conditions. 相似文献