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271.
272.
J. Beslin Joshi S. Geetha Birla Singh K. K. Kumar E. Kokiladevi L. Arul P. Balasubramanian D. Sudhakar 《Physiology and Molecular Biology of Plants》2015,21(1):35-42
An alpha-zein promoter isolated from maize containing P-box, E motif sequence TGTAAAGT, opaque-2 box and TATA box was studied for its tissue-specific expression in rice. A 1,098 bp promoter region of alpha-zein gene, fused to the upstream of gusA reporter gene was used for transforming rice immature embryos (ASD 16 or IR 64) via the particle bombardment-mediated method. PCR analysis of putative transformants demonstrated the presence of transgenes (the zein promoter, gusA and hpt). Nineteen out of 37 and two out of five events generated from ASD 16 and IR 64 were found to be GUS-positive. A histological staining analysis performed on sections of mature T1 seeds revealed that the GUS expression was limited to the endosperm and not to the pericarp or the endothelial region. GUS expression was observed only in the following seed development stages : milky (14–15 DAF), soft dough (17–18 DAF), hard dough (20–23 DAF), and mature stages (28–30 DAF) of zein-gusA transformed (T0) plants. On the contrary a constitutive expression of GUS was evident in CaMV35S-gusA plants. PCR and Southern blotting analyses on T1 plants demonstrated a stable integration and inheritance of transgene in the subsequent T1 generation. GUS assay on T2 seeds revealed that the expression of gusA gene driven by alpha-zein promoter was stable and tissue-specific over two generations. Results suggest that this alpha-zein promoter could serve as an alternative promoter to drive endosperm-specific expression of transgenes in rice and other cereal transformation experiments. 相似文献
273.
274.
Geetha Arumugam Monika Padmanaban Dhanya Krishnan Saranya Panneerselvam Surendran Rajagopal 《Biological trace element research》2011,142(3):424-434
Chronic pancreatitis is a serious condition associated with severe abdominal pain, and a significant percentage of patients
progresses to irreversible calcification in pancreas. The present study evaluates the degree to which the levels of trace
elements, copper, iron, selenium, zinc and haemoglobin-Fe3+, in blood, serum and pancreas have any role to play in the calcification process associated with fibrosis in pancreas. Twenty-seven
calcific (CCP) and 23 non-calcific chronic pancreatitis (CP) patients and equal number of age- and sex-matched normal volunteers
(50) were enrolled in the study. Surgically removed pancreatic tissue and blood samples were analysed for copper, iron, selenium,
zinc, protein, collagen and lipid peroxidation products in terms of malondialdehyde, protein carbonyls, glutathione, methemoglobin,
methemoglobin reductase and ceruloplasmin activity levels. We could find that the pancreatic tissue levels of copper, iron,
protein and collagen contents were significantly elevated in CCP patients when compared to CP patients. Serum levels of copper,
free ionic copper and iron were also elevated in CCP patients. The serum and the pancreatic tissue level of zinc and selenium
showed a significant decrease in CCP patients. The level of methemoglobin was elevated more significantly with the concomitant
decline in the activity of methemoglobin reductase. There was a positive correlation between the pancreatic level of copper
and iron with the collagen and protein levels. The results of the present study revealed that the levels of copper and iron,
the pro-oxidants and zinc and selenium may influence calcification process in CCP patients. Hypoxia-related tissue injury
due to the formation of oxidised haemoglobin may also contribute to the pathogenesis of calcification in pancreas. 相似文献
275.
Mycobacterium tuberculosis, the etiologic agent of tuberculosis (TB) possesses at least five genes predicted to encode proteins with NlpC/P60 hydrolase domains, including the relatively uncharacterized Rv2190c. As NlpC/P60 domain-containing proteins are associated with diverse roles in bacterial physiology, our objective was to characterize Rv2190c in M. tuberculosis growth and virulence. Our data indicate that lack of Rv2190c is associated with impaired growth, both in vitro and during an in vivo mouse model of TB. These growth defects are associated with altered colony morphology and phthiocerol dimycocerosate levels, indicating that Rv2190c is involved in cell wall maintenance and composition. In addition, we have demonstrated that Rv2190c is expressed during active growth phase and that its protein product is immunogenic during infection. Our findings have significant implications, both for better understanding the role of Rv2190c in M. tuberculosis biology and also for translational developments. 相似文献
276.
Geetha Ramaswami Monica Kaushik Soumya Prasad Raman Sukumar David Westcott 《Biotropica》2016,48(5):638-644
In the past century, our understanding of the processes driving plant invasion and its consequences for natural and anthropogenic systems has increased considerably. However, the management of invasive plants remains a challenge despite ever more resources being allocated to their removal. Often invasive plants targeted for ‘eradication’ are well‐established, have multiple modes of reproduction, long‐term seed banks, and strong associations with native and non‐native mutualists that ensure dispersal and facilitate spread. The pantropical weed, Lantana camara (Lantana), is one of the most invasive woody plants globally. We illustrate that, for Lantana, eradication is an unrealistic management goal given the short‐term removal approaches, irrespective of the effectiveness of removal methods. We assessed the role of dispersal by avian frugivores in the recolonization of managed areas by Lantana in the seasonally dry, tropical forests of northern and southern India. We estimated the distribution of Lantana, its dispersal potential and the proximity between managed areas and source populations. We found that Lantana was dispersed by many generalist frugivorous birds and that most managed areas were well within the median dispersal distance from source plants facilitating rapid recolonization of managed areas. We conclude that given the difficulty of eradicating long‐established invasive plants, management practices should entail long‐term monitoring and control in priority areas for as long as Lantana occurs in the landscape. 相似文献
277.
278.
Sriram D Yogeeswari P Senchani G Banerjee D 《Bioorganic & medicinal chemistry letters》2007,17(8):2372-2375
A series of new tetracycline derivatives has been synthesized by reacting appropriate tetracyclines, formaldehyde and secondary amino (piperazino) function of fluoroquinolones using microwave irradiation with the yield ranging from 41 evaluated for its anti-HIV, antimycobacterial activities and HIV-1 integrase (IN) enzyme inhibition studies. Among the synthesized compounds, compound 10 was found to be the most promising compound active against HIV-1 replication with EC(50) of 5.2 microM and was nontoxic to the CEM cells until 200 microM, and MIC of 0.2 microg/mL against Mycobacterium tuberculosis, with moderate inhibition of both 3'-processing and strand transfer steps of HIV-1 IN. 相似文献
279.
Geetha Velmourougane Ravinder Raju Gabriel Bricard Jin S. Im Gurdyal S. Besra Steven A. Porcelli Amy R. Howell 《Bioorganic & medicinal chemistry letters》2009,19(13):3386-3388
An α-galactosyl ceramide (α-GalCer) 2 was synthesized and evaluated for its ability to stimulate iNKT-cell proliferation and elicit T-helper cytokines, IL-4 and IFNγ. Compound 2 combines the acyl chain of the potent, Th2 biasing α-GalCer 1 with a sphingoid base of the same length as that found in OCH, which also exhibits Th2 skewing, Such complementation may enhance cytokine bias, which is thought to be important for therapeutic applications of iNKT cell stimulation. Two related α-GalCers, 3 and 4, with saturated acyl chains were prepared for comparison. 相似文献
280.
Zuben E. Sauna Chinyere Okunji Ryan C. Hunt Tanvi Gupta Courtni E. Allen Elizabeth Plum Adam Blaisdell Vahan Grigoryan Geetha S Robert Fathke Kenji Soejima Chava Kimchi-Sarfaty 《PloS one》2009,4(8)