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131.
Sathish Kumar Rabi Raja Singh Henry Finlay Godson Retna Ponmalar Paul Ravindran Sunil Dutt Sharma Subhashini John 《Reports of Practical Oncology and Radiotherapy》2021,26(1):93
BackgroundThe purpose of this study was to investigate the feasibility of MOSFET dosimeter in measuring eye dose during 2D MV portal imaging for setup verification in radiotherapy.Materials and methodsThe in-vivo dose measurements were performed by placing the dosimeters over the eyes of 30 brain patients during the acquisition of portal images in linear accelerator by delivering 1 MU with the field sizes of 10 × 10 cm2 and 15 × 15 cm2.ResultsThe mean doses received by the left and right eyes of 10 out of 30 patients when both eyes were completely inside the anterior portal field were found to be 2.56 ± 0.2 cGy and 2.75 ± 0.2, respectively. Similarly, for next 10 patients out of the same 30 patients the mean doses to left and right eyes when both eyes were completely out of the anterior portal fields were found to be 0.13 ± 0.02 cGy and 0.17 ± 0.02 cGy, respectively. The mean doses to ipsilateral and contralateral eye for the last 10 patients when one eye was inside the anterior portal field were found to be 3.28 ± 0.2 cGy and 0.36 ± 0.1 cGy, respectively.ConclusionThe promising results obtained during 2D MV portal imaging using MOSFET have shown that this dosimeter is well suitable for assessing low doses during imaging thereby enabling to optimize the imaging procedure using the dosimetric data obtained. In addition, the documentation of the dose received by the patient during imaging procedure is possible with the help of an in-built software in conjunction with the MOSFET reader module. 相似文献
132.
When an γ‐irradiated Dy‐, Tm‐, Sm‐ or Mn‐doped CaSO4 crystal is impulsively deformed, two peaks appear in the ML intensity versus time curve, whereby the first ML peak is found in the deformation region and the second in the post‐deformation region of the crystals. In this study, intensities Im1 and Im2 corresponding to first and second ML peaks, respectively, increased linearly with an impact velocity v0 of the piston used to deform the crystals, and times tm1 and tm2 corresponding to the first and second ML peaks, respectively, decreased with impact velocity. Total ML intensity initially increased with impact velocity and then reached a saturation value for higher values of impact velocity. ML intensity increased with increasing γ‐doses and size of crystals. Results showed that the electric field produced as a result of charging of newly‐created surfaces caused tunneling of electrons to the valence band of the hole‐trapping centres. The free holes generated moved in the valence band and their subsequent recombination with electron trapping centres released energy, thereby resulting in excitation of luminescent centres. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
133.
Malarial infection during pregnancy has been associated with maternal anemia and death, abortion, still-birth and is a major cause of low birth weight, an important risk factor for infant morbidity and mortality in endemic areas. The present study was designed to delineate the oxidative stress in various organs (liver, spleen, kidney, brain and placenta) of pregnant Plasmodium berghei infected BALB/c mice. It was observed that pregnant-infected mice had higher parasitaemia than nonpregnant-infected mice. Most notably, levels of malondialdehyde (MDA), a measure of lipid peroxidation, reduced glutathione (GSH) and superoxide dismutase (SOD) levels were significantly higher in the liver, spleen, kidney and brain of pregnant-infected mice compared with pregnant mice. Although MDA levels were significantly higher, GSH and SOD levels remained unaltered in the placenta of pregnant-infected mice compared with pregnant mice. Furthermore, catalase activity was significantly lower in all the organs of pregnant-infected mice compared with pregnant mice. Histopathological observations in the organs clearly show the cellular and morphological alterations that may be occurring due to increased lipid peroxidation. Taken together, the data suggest that the increased severity of malarial infection during pregnancy may be due to accentuated oxidative stress. 相似文献
134.
Anshu Sharma Rajinder Kaur Neha Sharma 《Physiology and Molecular Biology of Plants》2014,20(2):249-256
Micropropagation offers a great potential to produce millions of clonal individuals through tissue culture via induction of morphogenesis. The aim of this work was to obtain an efficient protocol for callus regeneration for Gentiana kurroo Royle. The morphogenic response of different explants (leaves, petioles, roots) varied and responded differently for regeneration according to combinations of growth regulators. The petiole explants were best responding for callus induction and subsequently for indirect and direct regeneration. The callus induction was achieved on MS basal + 1.0 mg/l benzyladenine (BA) and 3.00 mg/l naphthalene acetic acid (NAA). MS medium supplemented with 0.10 mg/l NAA and 1.0 mg/l thidiazuron (TDZ) was recorded as the best medium for indirect regeneration. However, for direct regeneration the maximum number of shoot emergence was observed on MS basal fortified with 0.10 mg/l NAA + 0.75 mg/l TDZ. Half strength MS basal supplemented with indole-3-butyric acid (IBA) 1.00 mg/l gave best response for root induction. Subsequently, the plantlets were transferred and 100 % survival rate was recorded only on autoclaved cocopeat. No morphological variations were recorded in the callus regenerated plantlets. 相似文献
135.
Dharam Pal Pathak Vidushi Sharma Sachin Kumar 《Bioorganic & medicinal chemistry letters》2018,28(9):1566-1569
Coumarin containing pyrazoline derivatives have been synthesized and tested as inhibitors of in vitro development of a chloroquine-sensitive (MRC-02) and chloroquine-resistant (RKL-2) strain of Plasmodium falciparum and in vivo Plasmodium berghei malaria. Docking study was also done on cysteine protease falcipain-2 which showed that the binding pose of C-14 molecule and epoxysuccinate, inhibitor of falcipain-2, binds in the similar pattern. The most active antimalarial compound was 3-(1-benzoyl-5-(4-flurophenyl)-4,5-dihydro-1H-pyrazol-3yl)-7-(diethyamino)-2H-chromen-2-one C-14, with an IC50 of 4.21?µg/ml provided complete protection to the infected mice at 24?mg/kg X 4?days respectively. 相似文献
136.
Preeti Apurve Sharma Neetu Verma Pradeep Kumar Burma 《Journal of plant biochemistry and biotechnology.》2018,27(4):443-452
TA29 and A9 are genes from Nicotiana tabacum and Arabidopsis thaliana respectively, which express in a tapetum specific manner. The upstream regulatory modules (URMs; i.e. the promoter and the 5′UTR) of these genes have been used in development of male sterile and restorer lines expressing the barnase and barstar genes for hybrid seed production. While initial studies show that these URMs drive the expression in a tapetum specific manner, there are no recordings of unintended (leaky) expression driven by these URMs at ectopic locations due to position effect in developed transgenic lines. The information on leaky expression driven by tissue specific URMs is important for their use in developing transgenic plants. The present study records the leaky activity of both these URMs in transgenic tobacco lines using β-glucuronidase as a reporter gene. Leaky activity was observed in about one-fourth of the lines developed with TA29. Most interestingly in these lines, the leaky expression of the reporter gene was observed to be restricted to the meristematic tip region of the roots and at the leaf gap from where leaf trace diverges from stem bundles. Such a restricted and unique pattern of leaky activity of a tissue specific promoter or a URM has never been reported before, including the URM of the A9 gene analyzed in the present study. This observation suggests the presence of cryptic cis-elements within the URM of TA29 gene that can possibly activate it in meristematic tissue when integrated at certain ectopic locations. The URM of the A9 gene was also observed to show leaky activity. However, there was no unique pattern as observed with that of TA29. Further, in the study we also show that while the smaller (290 bp) length of TA29 URM can be used to drive the expression of barnase gene to develop male sterile lines, it adversely affects the regeneration of transgenic tobacco lines due to leaky expression. This adverse effect is significantly reduced when the full length (1.5 kb) URM of the TA29 gene is used. 相似文献
137.
Singh Hemant Kumar Mondal Som Arunachalam Balraj Soman Anishkumar Sharma Pratibha Solanki C. S. 《Plasmonics (Norwell, Mass.)》2018,13(2):705-714
Plasmonics - In this paper, focus is on the light trapping surface in crystalline silicon (c-Si) solar cells where thinner c-Si wafers are expected to be used by industry to reduce the cost of cell... 相似文献
138.
Acinetobacter baumannii and Pseudomonas aeruginosa are pathogens capable of colonizing the same infection sites and employing N-acyl homoserine lactone (AHL) based quorum-sensing systems to co-ordinate biofilm formation. Hence, the effect of P. aeruginosa AHLs on biofilm formation by A. baumannii and vice versa were investigated using the biofilm impaired quorum sensing mutants, A. baumannii M2 (abaI::Km) and P. aeruginosa PAO-JP2. Complementing the mutants with heterologous, extracted and pure AHLs increased biofilm mass significantly. The surface area coverage and biovolume also increased significantly as observed by confocal scanning laser microscopy which corroborated scanning electron microscope analysis. Autoinducer synthase gene promoters of A. baumannii, P abaI-lacZ, and P. aeruginosa, P lasI-lacZ, were induced (p < 0.05) by heterologous AHLs. Growth of A. baumannii was not inhibited by pyocyanin of P. aeruginosa which may allow their co-existence and interaction in the clinical setting, thereby affecting the severity of combined infections and therapeutic measures to control them. 相似文献
139.
This study was conducted to study the long-term impact of bioinoculants, Azotobacter chroococcum and arbuscular mycorrhizal fungi (AMF) on growth and biomass yield of Jatropha curcas grown in nursery and in field conditions. The experiment was set up in a randomized block design, and the following treatments was designed (T1 = control, T2 = Azotobacter, T3 = inoculation with AMF, and T4 = inoculation with Azotobacter + AMF). Data on various growth attributes (shoot height and shoot diameter) and biochemical parameters [leaf relative water content (LRWC), sugars, protein, and photosynthetic pigments] were recorded up to 6 months in the nursery and in the field (18 months). Results pertaining to morpho-physiological traits showed Azotobacter and AMF consortia increase shoot height, shoot diameter, LRWC, sugars, proteins, and photosynthetic pigments over control under nursery conditions. Besides enhancing the plant growth, these bioinoculants helped in better establishment of Jatropha plants under field conditions. A significant improvement in the shoot height, shoot diameter, fruit yield/plant, and seed yield (g)/plant was evident in 18-month-old Jatropha plants under field conditions when Azotobacter and AMF were co-inoculated. This work supports the application of bioinoculants for establishment of Jatropha curcas in semi-arid regions. 相似文献
140.