75 research outputs found

    Relativistic K shell decay rates and fluorescence yields for Zn, Cd and Hg

    Full text link
    In this work we use the multiconfiguration Dirac-Fock method to calculate the transition probabilities for all possible decay channels, radiative and radiationless, of a K shell vacancy in Zn, Cd and Hg atoms. The obtained transition probabilities are then used to calculate the corresponding fluorescence yields which are compared to existing theoretical, semi-empirical and experimental results

    Oxygen-Independent Stabilization of Hypoxia Inducible Factor (HIF)-1 during RSV Infection

    Get PDF
    BACKGROUND: Hypoxia-inducible factor 1 (HIF)-1alpha is a transcription factor that functions as master regulator of mammalian oxygen homeostasis. In addition, recent studies identified a role for HIF-1alpha as transcriptional regulator during inflammation or infection. Based on studies showing that respiratory syncytial virus (RSV) is among the most potent biological stimuli to induce an inflammatory milieu, we hypothesized a role of HIF-1alpha as transcriptional regulator during infections with RSV. METHODOLOGY, PRINCIPAL FINDINGS: We gained first insight from immunohistocemical studies of RSV-infected human pulmonary epithelia that were stained for HIF-1alpha. These studies revealed that RSV-positive cells also stained for HIF-1alpha, suggesting concomitant HIF-activation during RSV infection. Similarly, Western blot analysis confirmed an approximately 8-fold increase in HIF-1alpha protein 24 h after RSV infection. In contrast, HIF-1alpha activation was abolished utilizing UV-treated RSV. Moreover, HIF-alpha-regulated genes (VEGF, CD73, FN-1, COX-2) were induced with RSV infection of wild-type cells. In contrast, HIF-1alpha dependent gene induction was abolished in pulmonary epithelia following siRNA mediated repression of HIF-1alpha. Measurements of the partial pressure of oxygen in the supernatants of RSV infected epithelia or controls revealed no differences in oxygen content, suggesting that HIF-1alpha activation is not caused by RSV associated hypoxia. Finally, studies of RSV pneumonitis in mice confirmed HIF-alpha-activation in a murine in vivo model. CONCLUSIONS/SIGNIFICANCE: Taking together, these studies suggest hypoxia-independent activation of HIF-1alpha during infection with RSV in vitro and in vivo

    The Importance of mitral valve prolapse doming volume in the assessment of left ventricular stroke volume with cardiac MRI

    Get PDF
    There remains a debate whether the ventricular volume within prolapsing mitral valve (MV) leaflets should be included in the left ventricular (LV) end-systolic volume, and therefore factored in LV stroke volume (SV), in cardiac magnetic resonance (CMR) assessments. This study aims to compare LV volumes during end-systolic phases, with and without the inclusion of the volume of blood on the left atrial aspect of the atrioventricular groove but still within the MV prolapsing leaflets, against the reference LV SV by four-dimensional flow (4DF). A total of 15 patients with MV prolapse (MVP) were retrospectively enrolled in this study. We compared LV SV with (LV SVMVP) and without (LV SVstandard) MVP left ventricular doming volume, using 4D flow (LV SV4DF) as the reference value. Significant differences were observed when comparing LV SVstandard and LV SVMVP (p < 0.001), and between LV SVstandard and LV SV4DF (p = 0.02). The Intraclass Correlation Coefficient (ICC) test demonstrated good repeatability between LV SVMVP and LV SV4DF (ICC = 0.86, p < 0.001) but only moderate repeatability between LV SVstandard and LV SV4DF (ICC = 0.75, p < 0.01). Calculating LV SV by including the MVP left ventricular doming volume has a higher consistency with LV SV derived from the 4DF assessment. In conclusion, LV SV short-axis cine assessment incorporating MVP dooming volume can significantly improve the precision of LV SV assessment compared to the reference 4DF method. Hence, in cases with bi-leaflet MVP, we recommend factoring in MVP dooming into the left ventricular end-systolic volume to improve the accuracy and precision of quantifying mitral regurgitation

    Comparative proteomic analysis on fruit ripening processes in two varieties of tropical mango (Mangifera indica)

    Get PDF
    Mango (Mangifera indica L.) is an economically important fruit. However, the marketability of mango is affected by the perishable nature and short shelf-life of the fruit. Therefore, a better understanding of the mango ripening process is of great importance towards extending its postharvest shelf life. Proteomics is a powerful tool that can be used to elucidate the complex ripening process at the cellular and molecular levels. This study utilized 2-dimensional gel electrophoresis (2D-GE) coupled with MALDI-TOF/TOF to identify differentially abundant proteins during the ripening process of the two varieties of tropical mango, Mangifera indica cv. ‘Chokanan’ and Mangifera indica cv ‘Golden Phoenix’. The comparative analysis between the ripe and unripe stages of mango fruit mesocarp revealed that the differentially abundant proteins identified could be grouped into the three categories namely, ethylene synthesis and aromatic volatiles, cell wall degradation and stress-response proteins. There was an additional category for differential proteins identified from the ‘Chokanan’ variety namely, energy and carbohydrate metabolism. However, of all the differential proteins identified, only methionine gamma-lyase was found in both ‘Chokanan’ and ‘Golden Phoenix’ varieties. Six differential proteins were selected from each variety for validation by analysing their respective transcript expression using reverse transcription-quantitative PCR (RT-qPCR). The results revealed that two genes namely, glutathione S-transferase (GST) and alpha-1,4 glucan phosphorylase (AGP) were found to express in concordant with protein abundant. The findings will provide an insight into the fruit ripening process of different varieties of mango fruits, which is important for postharvest management

    Relationship between psychological well-being and perceptions of stress among undergraduate dental students in Bengaluru city: A cross-sectional study

    No full text
    Introduction: The dental profession has been considered a stressful occupation. The origins of this stress may also lie in the process of dental education. The perception of stress is frequently influenced by one′s personal system of beliefs and attitudes. Aim: The aim was to assess the relationship between psychological well-being and perception of stress among undergraduate dental students in Bangalore city. Materials and Methods: A cross-sectional questionnaire survey was conducted among 800 1-4 th year dental students. Information on demographics, social background, and health behaviors were collected. The psychological general well-being (PGWB) index and the dental environment stress (DES) questionnaire were used to measure PGWB and perceptions of stress, respectively. Multiple intergroup comparisons were carried out using ANOVA. Correlation analysis was done to find out relationship between PGWB and DES. Regression analysis to find out the strongest predictor of PGWB. P <0.05 was considered as statistically significant. Results: There was no significant difference in PGWB among different year of study. Female students had significantly lower PGWB scores and higher DES scores than male students. The stress differed among different year of study with highest stress in final year students in all domains except for clinical/preclinical training, which was highest among 1 st year students. Correlational analysis showed a negative relationship between PGWB and DES score. Stepwise multiple regression analysis revealed that "workload," "patient treatment," "performance pressure" and "others" domains of stress were significant predictors of PGWB. Conclusion: This study revealed that the perception of stress is influenced by gender and health behaviors which in turn affect PGWB

    Titanium (III) reduction of dimethylglyoxime: Electrochemical and kinetic studies

    No full text
    176-179Titanium (III) mediated electroreduction of dimethyl glyoxime has been carried out in aqueous sulphuric acid medium and the reduction product has been isolated and characterised. The kinetic investigations have been carried out under stoichiometric and non-stoichiometric conditions at 306K. It has been found that the reaction follows overall second order kinetics, first order each in [Ti(III)] and [DMG] and fractional order in sulphuric acid. The effect of varying concentrations of Ti(III), DMG, H2SO4, ionic strength, and solvent composition has been studied. Effect of temperature has also been studied and activation parameters have been computed from Arrhenius and Eyring plots
    corecore