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81.
Sathiyan Saminathan Varatharaj Chandraraj C.H. Sridhar Ravikumar Manickam 《Reports of Practical Oncology and Radiotherapy》2012,17(3):157-162
AimTo compare the measured and calculated individual and composite field planar dose distribution of Intensity Modulated Radiotherapy plans.Materials and methodsThe measurements were performed in Clinac DHX linear accelerator with 6 MV photons using Matrixx device and a solid water phantom. The 20 brain tumor patients were selected for this study. The IMRT plan was carried out for all the patients using Eclipse treatment planning system. The verification plan was produced for every original plan using CT scan of Matrixx embedded in the phantom. Every verification field was measured by the Matrixx. The TPS calculated and measured dose distributions were compared for individual and composite fields.Results and discussionThe percentage of gamma pixel match for the dose distribution patterns were evaluated using gamma histogram. The gamma pixel match was 95–98% for 41 fields (39%) and 98% for 59 fields (61%) with individual fields. The percentage of gamma pixel match was 95–98% for 5 patients and 98% for other 12 patients with composite fields. Three patients showed a gamma pixel match of less than 95%. The comparison of percentage gamma pixel match for individual and composite fields showed more than 2.5% variation for 6 patients, more than 1% variation for 4 patients, while the remaining 10 patients showed less than 1% variation.ConclusionThe individual and composite field measurements showed good agreement with TPS calculated dose distribution for the studied patients. The measurement and data analysis for individual fields is a time consuming process, the composite field analysis may be sufficient enough for smaller field dose distribution analysis with array detectors. 相似文献
82.
Polyplexes sensitive to redox potential gradients represent promising gene delivery vectors. High molecular weight polypeptides containing disulfide bonds in the backbone were synthesized by an oxidative copolymerization of a histidine-rich peptide (HRP) and a nuclear localization sequence (NLS) peptide. The synthetic approach allowed an easy synthesis of reducible copolypeptides (rCPP) with different relative contents of the HRP and NLS sequences. Cytotoxicity and transfection activity of rCPP-based DNA polyplexes were evaluated in vitro. In comparison with control polyethylenimine (PEI), only minimum toxic effects of rCPPs were observed on the metabolic activity and membrane integrity of human endothelial cells. These findings are predominantly ascribed to favorable structural features like lower charge density and higher chain rigidity of the rCPPs compared to PEI and also to a reductive intracellular and plasma membrane degradation. Transfection activity in all tested cell lines increased with increasing content of the HRP sequence in the rCPPs, while no clearly measurable effect of the NLS sequence was found. 相似文献
83.
Ramar Thangam Palani Gunasekaran Krishnasamy Kaveri Gnanaiah Sridevi Shenbagamoorthy Sundarraj Manickam Paulpandi Soundarapandian Kannan 《Process Biochemistry》2012,47(8):1243-1249
Animal venoms and toxins are potential bioresources that have been known to mankind as a therapeutic tool for more than a century through folk and traditional medicine. The purified “disintegrin protein” (64 kDa) from the venom of the Indian cobra snake (Naja naja) exhibited cytotoxic effects of various types of human cancer cell lines such as breast cancer (MCF-7), lung cancer (A549) and liver cancer (HepG2). In vitro cytotoxicity, DNA fragmentation, an apoptotic assay and a cell cycle analysis were performed to evaluate the anticancer activity of disintegrin against the above cell lines. The IC50 value of disintegrin was determined to be 2.5 ± 0.5 μg/mL, 3.5 ± 0.5 μg/mL, and 3 ± 0.5 μg/mL for the MCF-7, A549 and HepG2 cell lines respectively. Moreover, the increased distribution of G0/G1 and S phase led to decreased populations of cells in the G2/M phase of MCF-7, HepG2 and A549 cells. 相似文献
84.
K.C. Majumdar K. Nasaruddin K. Ravinder C.S. Sundaram P. Manickam S. Shivaji 《Marine biotechnology (New York, N.Y.)》1999,1(3):221-229
Changes in the phosphorus-containing metabolites were monitored by 31P nuclear magnetic resonance in the developing embryos of Clarias batrachus. Phosphomonoester, yolk phosphoprotein, phosphocreatine, ATP, and inorganic phosphate (Pi) were consistently observed in all
the developmental stages of C. batrachus. None of these phosphometabolites exhibited any significant change in their concentration up to the blastula stage, whereas
distinct decrease in all except inorganic phosphate was observed in the fry stage. Concomitantly an increase in the concentration
of inorganic phosphate was observed. Further, from the resonance positions of α, β, and γ phosphate groups of ATP, it was
evident that the ATP molecules in vivo were liganded either to Ca2+ or Mg2+. This study also revealed that the intracellular pH of the developing embryos was approximately 7.05 up to the gastrula stage,
after which it decreased in the fry stage to 6.98 units.
Received August 10, 1998; accepted November 3, 1998. 相似文献
85.
86.
Protective action of curcumin and nano-curcumin against arsenic-induced genotoxicity in rats in vivo
Palanisamy Sankar Avinash Gopal Telang Kalaivanan Ramya Karunakaran Vijayakaran Manickam Kesavan Souvendra Nath Sarkar 《Molecular biology reports》2014,41(11):7413-7422
We explored whether nanoformulation of curcumin can cause better protective effect than free curcumin against arsenic-induced genotoxicity. Curcumin-loaded Poly(lactic-co-glycolic acid) nanoparticles (CUR-NP) were prepared by emulsion technique. The CUR-NP were water soluble and showed biphasic release pattern. Rats were divided into 5 groups of 6 each. Group I served as the control. Group II rats were exposed to sodium arsenite (25 ppm) daily through drinking water for 42 days. Groups III, IV and V were maintained as in Group II, however, they were also administered empty nanoparticle, curcumin (100 mg/kg bw) and CUR-NP (100 mg/kg bw), respectively, by oral gavage during the last 14 days of arsenic exposure. On the 43rd day, genotoxic effects were evaluated in bone marrow cells. Arsenic increased chromosomal aberrations, micronuclei formation and DNA damage. Both free curcumin and CUR-NP attenuated these arsenic-mediated genotoxic effects. However, the result suggests that nanoformulation have better protective effect than free curcumin at the same dose level. 相似文献
87.
Leptospermum flavescens Sm. (Myrtaceae), locally known as ‘Senna makki’ is a smallish tree that is widespread and recorded to naturally occur in the montane regions above 900 m a.s.l from Burma to Australia. Although the species is recorded to be used traditionally to treat various ailments, there is limited data on biological and chemical investigations of L. flavescens. The aim of the present study was to investigate and understand the ability of L. flavescens in inducing cell death in lung cancer cells. The cytotoxic potentials of the extraction yields (methanol, hexane, ethyl acetate and water extracts as wells as a semi pure fraction, LF1) were evaluated against two human non-small cell lung carcinoma cell lines (A549 and NCI-H1299) using the MTT assay. LF1 showed the greatest cytotoxic effect against both cell lines with IC50 values of 7.12 ± 0.07 and 9.62 ± 0.50 μg/ml respectively. LF1 treated cells showed a sub-G1 region in the cell cycle analysis and also caused the presence of apoptotic morphologies in cells stained with acridine orange and ethidium bromide. Treatment with LF1 manifested an apoptotic population in cells that were evaluated using the Annexin V/ propidium iodide assay. Increasing dosage of LF1 caused a rise in the presence of activated caspase-3 enzymes in treated cells. Blockage of cell cycle progression was also observed in LF1-treated cells. These findings suggest that LF1 induces apoptosis and cell cycle arrest in treated lung cancer cells. Further studies are being conducted to isolate and identify the active compound as well to better understand the mechanism involved in inducing cell death. 相似文献
88.
Vasanthakumar SathyaSelvabalaDinesh Kirupha Selvaraj Jalagandeeswaran KalimuthuPremkumar Manickam Periyaraman Sivanesan Subramanian 《Bioresource technology》2011,102(2):1066-1072
In this study, a two-step process was developed to produce biodiesel from Calophyllum inophyllum oil. Pre-treatment with phosphoric acid modified β-zeolite in acid catalyzed esterification process preceded by transesterification which was done using conventional alkali catalyst potassium hydroxide (KOH). The objective of this study is to investigate the relationship between the reaction temperatures, reaction time and methanol to oil molar ratio in the pre-treatment step. Central Composite Design (CCD) and Response Surface Methodology (RSM) were utilized to determine the best operating condition for the pre-treatment step. Biodiesel produced by this process was tested for its fuel properties. 相似文献
89.
Jyoti ChhibberGoel Manickam Yogavel Amit Sharma 《Protein science : a publication of the Protein Society》2021,30(9):1793
Malaria is a parasitic illness caused by the genus Plasmodium from the apicomplexan phylum. Five plasmodial species of P. falciparum (Pf), P. knowlesi, P. malariae, P. ovale, and P. vivax (Pv) are responsible for causing malaria in humans. According to the World Malaria Report 2020, there were 229 million cases and ~ 0.04 million deaths of which 67% were in children below 5 years of age. While more than 3 billion people are at risk of malaria infection globally, antimalarial drugs are their only option for treatment. Antimalarial drug resistance keeps arising periodically and thus threatens the main line of malaria treatment, emphasizing the need to find new alternatives. The availability of whole genomes of P. falciparum and P. vivax has allowed targeting their unexplored plasmodial enzymes for inhibitor development with a focus on multistage targets that are crucial for parasite viability in both the blood and liver stages. Over the past decades, aminoacyl‐tRNA synthetases (aaRSs) have been explored as anti‐bacterial and anti‐fungal drug targets, and more recently (since 2009) aaRSs are also the focus of antimalarial drug targeting. Here, we dissect the structure‐based knowledge of the most advanced three aaRSs—lysyl‐ (KRS), prolyl‐ (PRS), and phenylalanyl‐ (FRS) synthetases in terms of development of antimalarial drugs. These examples showcase the promising potential of this family of enzymes to provide druggable targets that stall protein synthesis upon inhibition and thereby kill malaria parasites selectively. 相似文献
90.
Abebe AT Devoid SJ Sugumaran M Etter R Robinson WE 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2007,147(1):74-81
Histidine-rich Glycoprotein (HRG) is a metal-binding protein described from the blood plasma of a pteriomorph bivalve, the marine mussel Mytilus edulis L. We demonstrate here, using Cd-Immobilized Metal Affinity Chromatography (IMAC), SDS-PAGE, Western Blotting, and ELISA, that HRG is present in three additional pteriomorphs and two heterodont bivalves. ELISA indicates that HRG is the predominant blood plasma protein in all six species (41 to 61% of total plasma proteins by weight). Thus, HRG appears to be a widespread metal-binding protein in the plasma of bivalves. 相似文献