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71.
Arumugam Karthikeyan 《Symbiosis (Philadelphia, Pa.)》2017,72(2):89-94
Impact of different levels of elevated CO 2 on the activity of Frankia (Nitrogen-fixing actinomycete) in Casuarina equisetifolia rooted stem cuttings has been studied to understand the relationship between C. equisetifolia, Frankia and CO2. The stem cuttings of C. equietifolia were collected and treated with 2000 ppm of Indole Butyric Acid (IBA) for rooting. Thus vegetative propagated rooted stem cuttings of C. equisetifolia were inoculated with Frankia and placed in the Open top chambers (OTC) with elevated CO2 facilities. These planting stocks were maintained in the OTC for 12 months under different levels of elevated CO2 (ambient control, 600 ppm, 900 ppm). After 12 months, the nodule numbers, bio mass, growth, and photosynthesis of C. equisetifolia rooted stem cuttings inoculated with Frankia were improved under 600 ppm of CO2. The rooted stem cuttings of C. equisetifolia inoculated with Frankia showed a higher number of nodules under 900 ppm of CO2 and cuttings without Frankia inoculation exhibited poor growth. Tissue Nitrogen (N) content was also higher under 900 ppm of CO2 than ambient control and 600 ppm levels. The photosynthetic rate was higher (17.8 μ mol CO2 m?2 s?1) in 900 ppm of CO2 than in 600 ppm (13.2 μ mol CO2 m?2 s?1) and ambient control (8.3 μ mol CO2 m?2 s?1). This study showed that Frankia can improve growth, N fixation and photosynthesis of C. equietifolia rooted stem cuttings under extreme elevated CO2 level conditions (900 ppm). 相似文献
72.
Electrochemical Energy Storage with a Reversible Nonaqueous Room‐Temperature Aluminum–Sulfur Chemistry
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A reversible room‐temperature aluminum–sulfur (Al‐S) battery is demonstrated with a strategically designed cathode structure and an ionic liquid electrolyte. Discharge–charge mechanism of the Al‐S battery is proposed based on a sequence of electrochemical, microscopic, and spectroscopic analyses. The electrochemical process of the Al‐S battery involves the formation of a series of polysulfides and sulfide. The high‐order polysulfides (Sx2?, x ≥ 6) are soluble in the ionic liquid electrolyte. Electrochemical transitions between S62? and the insoluble low‐order polysulfides or sulfide (Sx 2?, 1 ≤ x < 6) are reversible. A single‐wall carbon nanotube coating applied to the battery separator helps alleviate the diffusion of the polysulfide species and reduces the polarization behavior of the Al‐S batteries. 相似文献
73.
Arumugam Dhanesh Gandhi Dhandapani Kayal Vizhi Kubendiran Lavanya V.N. Kalpana V. Devi Rajeswari Ranganathan Babujanarthanam 《Biochemistry and Biophysics Reports》2017
The main objective of this research is to investigate the anti-biofilm and anti-bacterial activity of Sesbania grandiflora (S. grandiflora) against Staphylococcus aureus. S. grandiflora extract were prepared and analyzed with UV –Vis spectroscopy, Fourier transform infrared spectroscopy, Dynamic light scattering. Biofilm forming pathogens were identified by congo-red assay. Quantification of Extracellular polymeric substance (EPS) particularly protein and carbohydrate were calculated. The efficacy of the herbal extract S. grandiflora and its inhibition against the pathogenic strain of S. aureus was also evaluated. The gradual decrease or disappearance of peaks reveals the reduction of protein and carbohydrate content in the EPS of S. aureus when treated with S. grandiflora. The antibacterial activity of S. grandiflora extract against the bacterial strain S. aureus showed that the extract were more active against the strain. To conclude, anti-biofilm and antibacterial efficacy of S. grandiflora plays a vital role over biofilm producing pathogens and act as a good source for controlling the microbial population. 相似文献
74.
Arumugam Geetha Panneerselvam Saranya Sam Annie Jeyachristy Rajagopal Surendran Arunachalam Sundaram 《Biological trace element research》2009,130(3):229-240
Altered copper homeostasis and oxidative stress have been observed in patients with hepatocellular carcinoma. Non-ceruloplasmin
copper, the free form, is a potent pro-oxidant than the protein bound copper. The aim of the present study was to evaluate
which form of copper can be correlated with the oxidative stress in the circulation and in the malignant liver tissues of
hepatocellular carcinoma patients. Hepatocellular carcinoma patients (grades II and III, n = 18) were enrolled in this study. Serum levels of total, free and bound copper, ceruloplasmin, iron, iron-binding capacity,
lipid peroxidation products, and enzymatic and non-enzymatic antioxidants were quantified in serum and in malignant liver
tissues and compared with those of normal samples (n = 20). A significant positive correlation between the serum non-ceruloplasmin copper and lipid peroxidation products and
negative correlation with antioxidants were observed in hepatocellular carcinoma patients. In liver tissue, glutathione peroxidase,
superoxide dismutase, and catalase activity were significantly decreased with concomitant elevation in oxidative stress markers.
Our experiment revealed that the elevation in non-ceruloplasmin copper has high relevance with the oxidative stress than the
bound copper. 相似文献
75.
A synthetic androgen 7α-Methyl-19-nortestosterone (MENT) has a potential for therapeutic use in ‘androgen replacement therapy’ for hypogonadal men or as a hormonal male-contraceptive in normal men. Its tissue distribution, excretion and metabolic enzyme(s) have not been reported. Therefore, the present study tested the distribution and excretion of MENT in Sprague-Dawley rats castrated 24 h prior to the injection of tritium-labeled MENT (3H-MENT). Rats were euthanized at different time intervals after dosing, and the amount of radioactivity in various tissues/organs was measured following combustion in a Packard oxidizer. The radioactivity (% injected dose) was highest in the duodenal contents in the first 30 min of injection. Specific uptake of the steroid was observed in target tissues such as ventral prostate and seminal vesicles at 6 h, while in other tissues radioactivity equilibrated with blood. Liver and duodenum maintained high radioactivity throughout, as these organs were actively involved in the metabolism and excretion of most drugs. The excretion of 3H-MENT was investigated after subcutaneous injection of 3H-MENT into male rats housed in metabolic cages. Urine and feces were collected at different time intervals (up to 72 h) following injection. Results showed that the radioactivity was excreted via feces and urine in equal amounts by 30 h.Aiming to identify enzyme(s) involved in the MENT metabolism, we performed in vitro metabolism of 3H-MENT using rat and human liver microsomes, cytosol and recombinant cytochrome P450 (CYP) isozymes. The metabolites were separated by thin-layer chromatography (TLC). Three putative metabolites (in accordance with the report of Agarwal and Monder [Agarwal AK, Monder C. In vitro metabolism of 7α-methyl-19-nortestosterone by rat liver, prostate, and epididymis. Endocrinology 1988;123:2187-93]), [i] 3-hydroxylated MENT by both rat and human liver cytosol; [ii] 16α-hydroxylated MENT (a polar metabolite) by both rat and human hepatic microsomes; and [iii] 7α-methyl-19-norandrostenedione (a non-polar metabolite) by human hepatic microsomes, were obtained. By employing chemical inhibitors and specific anti-CYP antibodies, 3H-MENT was found to be metabolized specifically by rat CYP 2C11 and 3-hydroxysteroid dehydrogenase (3-HSD) enzymes whereas in humans it was accomplished by CYP 3A4, 17β-hydroxysteroid dehydrogenase (17β-HSD) and 3-HSD enzymes. 相似文献
76.
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78.
Vijaya Ramachandran Thiruvengadam Arumugam Robert Langley Rosa F. Hwang Pablo Vivas-Mejia Anil K. Sood Gabriel Lopez-Berestein Craig D. Logsdon 《PloS one》2009,4(10)
Background
Adrenomedullin (AM) is highly expressed in pancreatic cancer and stimulates pancreatic cancer cells leading to increased tumor growth and metastasis. The current study examines the role of specific AM receptors on tumor and cells resembling the tumor microenvironment (human pancreatic stellate - HPSC, human umbilical vein – HUVEC and mouse lung endothelial cells - MLEC).Methods and Findings
AM receptors ADMR and CRLR were present in HPSC, HUVEC and MLECs while PDAC cells possessed only ADMR receptors as assessed by RT-PCR and western blotting. All cell lines expressed and secreted AM as indicated by ELISA. The growth of each of the cell lines was stimulated by exogenous AM and inhibited by the antagonist AMA. AM also stimulated in vitro angiogenesis assessed by polygon formation of endothelial cell lines. SiRNA-mediated silencing of ADMR, but not CRLR, reduced basal growth of all cells examined and reduced polygon formation of endothelial cells in vitro. Orthotopic tumors developed with shADMR bearing cancer cells had dramatically reduced primary tumor volume (>90%) and lung and liver metastasis compared to shControl bearing cells. To validate ADMR as a potential therapeutic target, in vivo studies were conducted using neutral nanoliposomes to systemically deliver human siRNA to ADMR to silence human cancer cells and mouse siRNA to ADMR to silence mouse tumor stromal cells. Systemic silencing of both human and mouse ADMR had no obvious adverse effects but strongly reduced tumor development.Conclusion
ADMR mediates the stimulatory effects of AM on cancer cells and on endothelial and stellate cells within the tumor microenvironment. These data support the further development of ADMR as a useful target treatment of pancreatic cancer. 相似文献79.
80.
Jagannath A Sodhi YS Gupta V Mukhopadhyay A Arumugam N Singh I Rohatgi S Burma PK Pradhan AK Pental D 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(6):1091-1103
Oil content and oil quality fractions (viz., oleic, linoleic and linolenic acid) are strongly influenced by the erucic acid
pathway in oilseed Brassicas. Low levels of erucic acid in seed oil increases oleic acid content to nutritionally desirable
levels, but also increases the linoleic and linolenic acid fractions and reduces oil content in Indian mustard (Brassica juncea). Analysis of phenotypic variability for oil quality fractions among a high-erucic Indian variety (Varuna), a low-erucic east-European
variety (Heera) and a zero-erucic Indian variety (ZE-Varuna) developed by backcross breeding in this study indicated that
lower levels of linoleic and linolenic acid in Varuna are due to substrate limitation caused by an active erucic acid pathway
and not due to weaker alleles or enzyme limitation. To identify compensatory loci that could be used to increase oil content
and maintain desirable levels of oil quality fractions under zero-erucic conditions, we performed Quantitative Trait Loci
(QTL) mapping for the above traits on two independent F1 doubled haploid (F1DH) mapping populations developed from a cross
between Varuna and Heera. One of the populations comprised plants segregating for erucic acid content (SE) and was used earlier
for construction of a linkage map and QTL mapping of several yield-influencing traits in B. juncea. The second population consisted of zero-erucic acid individuals (ZE) for which, an Amplified Fragment Length Polymorphism
(AFLP)-based framework linkage map was constructed in the present study. By QTL mapping for oil quality fractions and oil
content in the ZE population, we detected novel loci contributing to the above traits. These loci did not co-localize with
mapped locations of the fatty acid desaturase 2 (FAD2),
fatty acid desaturase 3 (FAD3) or fatty acid elongase (FAE) genes unlike those of the SE population wherein major QTL were found to coincide with mapped locations of the FAE genes. Some of the new loci identified in the ZE population could be detected as ‘weak’ contributors (with LOD < 2.5) in
the SE population in which their contribution to the traits was “masked” due to pleiotropic effects of erucic acid genes.
The novel loci identified in this study could now be used to improve oil quality parameters and oil content in B. juncea under zero-erucic conditions. 相似文献