9 research outputs found

    bcl-2 immunoreactivity but not p53 accumulation associated with tumour response to radiotherapy in cervical carcinoma

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    Purpose: This study seeks to define the role of pretreatment expression of the tumour-suppressor p53 protein and the anti-apoptotic protein bcl-2 and their relationship to tumour response to radiotherapy in cervical carcinoma. Methods: A total of 101 patients were evaluated and the possibility of a correlation done between the pretreatment status of the two proteins and clinical outcome following radiotherapy was investigated. Such patients were either disease-free (group 1, n=65) or had residual/recurrent disease (group 2, n=36) at a 16-month follow-up. p53 and bcl-2 protein expression was determined by immunocytochemistry. The presence of mutant p53 was detected by a mutant specific p53 enzyme-linked immunosorbent assay. Results: There was no correlation between p53 immunoreactivity or the presence of mutant p53 protein and disease status after treatment. Expression of bcl-2 protein, however, showed significant pretreatment correlations with the final disease outcome (r=0.643, P=0.0001). Moreover the odds ratio of a tumour expressing moderate to intense levels of bcl-2 responding poorly to radiotherapy was 27.2 (95% CI 6.0, 123.3). Conclusions: bcl-2 protein functions in an anti-oxidant pathway to prevent apoptosis. Since radiotherapy efficacy depends on adequate DNA damage caused by free-radical generation, increased expression of bcl-2 may result in tumours becoming less responsive to radiation. Mutation of the p53 gene, however, is a rare event in cervical cancer. Since bcl-2 is negatively regulated by p53, it could be presumed that the p53 detected in the tumour cells may be non-functional or inactive possibly because of interaction with proteins such as E6 or mdm-2

    A study on the interpretation of spontaneous potential and resistivity logs in layered aquifer sequence of Pondicherry Region, South India

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    Geophysical logs provide a strong mechanism for interpretation and determination of the depositional environments, facies and also help in interpretations of hydrogeologic units. Spontaneous potential (SP) and resistivity logs can be used as an indicator of textural parameters. Pondicherry region has a complicated geology and with formation of different ages. The boreholes (BH) of this region are examined for litholog, SP and resistivity from four different BH locations, viz, Ariyankuppam, Chinnaverampattinam, Thavalakuppam and Nallavadu. These locations were studied and interpreted by using the shapes of the curves to identify the depositional environments, and this was later compared with the vertical litholog profile. Comparing the variation of these logs, the lateral variation of sedimentary facies was also attempted. The average resistivity values of Ariyankuppam, Chinnaverampattinam, Thavalakuppam and Nallavadu are 42.4, 30.4, 50.4 and 28.3 Ωm, respectively. Majority of the resistivity values corresponds from fine- to medium-grained sand, clayey pebbles, fine to very coarse sand and clayey sand with lignite. Frequency of resistivity values in each BH were identified for determining the dominant representative grain size. The study has pointed out the lithological variation of the system laterally and vertically using geophysical well logs

    Neoarchean-mesoproterozoic mafic dyke swarms of the indian shield mapped using google earth™ images and arcgis™, and links with large igneous provinces

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    We present dyke swarm maps generated using Google Earth™ images, ArcGIS™, field data, and available geochronological ages of Neoarchean-Mesoproterozoic (ranging in age from ~2.80 to ~1.10Â Ga) mafic dyke swarms and associated magmatic units of the different Archean cratons of the Indian shield which represent the plumbing system of Large Igneous Provinces (LIPs). The spatial and temporal distributions together with the trends of the dyke swarms provide important informations about geodynamics. Twenty four dyke swarms (17 have been precisely dated), mostly mafic in nature, have been mapped from the different cratons and named/re-named to best reflect their location, trend, distribution and distinction from other swarms. We have identified 14 distinct magmatic events during the Neoarchean-Mesoproterozoic in the Indian shield. These intraplate magmatic events (many of LIP scale) of the Indian shield and their matches with coeval LIPs on other crustal blocks suggest connections of the Indian shield within known supercontinents, such as Kenorland/Superia (~2.75–2.07Â Ga), Columbia/Nuna (1.90–1.38Â Ga), and Rodinia (1.20–0.72Â Ga). However, further detailed U–Pb geochronology and associated paleomagnetism are required to come to any definite constraints on the position of the Indian cratons within these supercontinents
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