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91.
Khadijeh Zare Hossein Nazemiyeh Ali Movafeghi Mahmood Khosrowshahli Alireza Motallebi-Azar Mohammadreza Dadpour Yadollah Omidi 《Plant Cell, Tissue and Organ Culture》2010,100(2):157-164
An in vitro cell suspension culture of Echium italicum was established and assayed for the production of shikonin and alkannin derivatives. Callus tissues were induced from cotyledon
explants of the plant incubated onto the solidified B5 medium. A two-liquid-phase system suspension culture was then established
to elicit pigments of shikonin and alkannin derivatives using liquid paraffin. The presence of liquid paraffin efficiently
induced production of pigments in cultured cells. The production and/or accumulation of these compounds in the E. italicum cells was examined using fluorescence microscopy as the naphthoquinone molecules display autofluorescent properties. Phytochemical
analysis of the n-hexane extract of the medium was also carried out using preparative HPLC. The chemical structure of shikonin and alkannin
derivatives were characterized by UV, 1H-NMR, and 13C-NMR techniques. Based on our findings, this bioprocess engineering approach
resulted in induction of shikonin and alkannin derivatives, whereupon it may be recruited for production of these important
secondary metabolites. 相似文献
92.
Morteza Yousefzadi Mozafar Sharifi Mehrdad Behmanesh Alireza Ghasempour Elisabeth Moyano Javier Palazon 《Biotechnology letters》2010,32(11):1739-1743
Treatment of Linum album cell cultures with 10 μM salicylic acid (SA) for 3 days improved podophyllotoxin (PTOX) production up to 333 μg/g dry weight
(DW): over three times that of the control cultures. qPCR analyses showed that in SA-treated cells, the expression of the
genes coding for phenylalanine ammonia-lyase (PAL), cinnamoyl-CoA reductase (CCR) and cinnamyl-alcohol dehydrogenase (CAD), all involved in the first steps of PTOX biosynthesis, also increased reaching a peak 8–12 h after the treatment. Expression
of the pinoresinol-lariciresinol reductase gene (PLR), which is involved in one of the last biosynthetic steps, was not affected by SA. The selective action of SA on these genes
can be applied to control the biotechnological production of this anticancer agent. 相似文献
93.
94.
Allothrombium clavatum sp. n. with reduced inner claw of tarus III, one seta on coxa II, clavate dorsal idiosomal setae and 3-lobed posterior margin
of scutum, collected as ectoparasite of an undetermined aphid, is described and illustrated from the central part of Montenegro
(Balkan Peninsula). A key to world species of Allothrombium (larva) is presented. 相似文献
95.
Regional ecosystem structure and function: ecological insights from remote sensing of tropical forests 总被引:7,自引:1,他引:6
Chambers JQ Asner GP Morton DC Anderson LO Saatchi SS Espírito-Santo FD Palace M Souza C 《Trends in ecology & evolution》2007,22(8):414-423
Ecological studies in tropical forests have long been plagued by difficulties associated with sampling the crowns of large canopy trees and large inaccessible regions, such as the Amazon basin. Recent advances in remote sensing have overcome some of these obstacles, enabling progress towards tackling difficult ecological problems. Breakthroughs have helped transform the dialog between ecology and remote sensing, generating new regional perspectives on key environmental gradients and species assemblages with ecologically relevant measures such as canopy nutrient and moisture content, crown area, leaf-level drought responses, woody tissue and surface litter abundance, phenological patterns, and land-cover transitions. Issues that we address here include forest response to altered precipitation regimes, regional disturbance and land-use patterns, invasive species and landscape carbon balance. 相似文献
96.
97.
Alimohammadian MH Darabi H Malekzadeh S Mahmoodzadeh-Niknam H Ajdary S Khamesipour A Bahonar A Mofarrah A 《Microbiology and immunology》2007,51(10):1003-1011
The immune responses of individuals exposed to Leishmania major were evaluated and compared with those of non-exposed volunteers. Forty-one patients with active lesion(s), 43 healed individuals, 15 vaccinees 1 month or 1 year post vaccination, and 15 non-exposed volunteers were studied. Leishmanin skin test (LST) response, proliferative response of lymphocyte (PRL) to L. major antigen, IFN-gamma and IL-4 production, and percentage of L. major-specific CD4+, CD8+ and CD16+/CD56+ cells in peripheral blood mononuclear cells were assessed. Data showed positive LST (>5 mm) in 92% of patients, 98% of healed, and 80% or 43% of vaccinees 1 month and 1 year post vaccination, respectively. Positive PRL (SI>2.5) was displayed in 90%, 84%, 46% and 7% of patients, healed, vaccinated (post 1 year) and non-exposed donors, respectively. The mean +/-S.E. of IFN-gamma was 924 +/- 149, 1,278 +/- 185, 470 +/- 282 or 258 +/- 82 pg/ml in patients, healed cases and vaccinees after 1 month or 1 year, respectively. Positive IFN-gamma responders (>300 pg/ml) were shown in 72% of patients, 81% of healed cases, 31% or 39% of vaccinees and 0% of non-exposed donors. A reduced percentage of CD4+ T-cells and an increased percentage of NK cells were found in exposed individuals compared to non-exposed donors. The data indicated that exposure to L. major modulates the proportion of CD4+ T cells and increases NK cells percentage. However, the cellular immune responses including induction of LST, and IFN-gamma production are increased in exposed individuals. 相似文献
98.
Homing endonucleases are site-specific and rare cutting endonucleases often encoded by intron or intein containing genes. They lead to the rapid spread of the genetic element that hosts them by a process termed 'homing'; and ultimately the allele containing the element will be fixed in the population. PI-SceI, an endonuclease encoded as a protein insert or intein within the yeast V-ATPase catalytic subunit encoding gene (vma1), is among the best characterized homing endonucleases. The structures of the Sce VMA1 intein and of the intein bound to its target site are known. Extensive biochemical studies performed on the PI-SceI enzyme provide information useful to recognize critical amino acids involved in self-splicing and endonuclease functions of the protein. Here we describe an insertion of the Green Fluorescence Protein (GFP) into a loop which is located between the endonuclease and splicing domains of the Sce VMA1 intein. The GFP is functional and the additional GFP domain does not prevent intein excision and endonuclease activity. However, the endonuclease activity of the newly engineered protein was different from the wild-type protein in that it required the presence of Mn(2+) and not Mg(2+) metal cations for activity. 相似文献
99.
Samadi Mitra Beigi Laleh Yadegari Fatemeh Ansari Alireza Madjid Majidzadeh-A Keivan Eskordi Maryam Farahmand Leila 《Genetica》2022,150(5):289-297
Genetica - Although predicting the effects of variants near intron-exon boundaries is relatively straightforward, predicting the functional Exon Splicing Enhancers (ESEs) and the possible effects... 相似文献
100.
Farrokhzad Yusuf Babaei Alireza Yadollahi Abbas Kashkooli Arman Beyraghdar Mokhtassi-Bidgoli Ali Hesami Shahriar 《Plant Cell, Tissue and Organ Culture》2022,149(3):535-548
Plant Cell, Tissue and Organ Culture (PCTOC) - We tested the feasibility to promote growth and shoot proliferation of Phalaenopsis through different wavelengths of LED and fluorescent. Therefore,... 相似文献