5 research outputs found

    Pyrosequencing versus methylation-specific PCR for assessment of MGMT methylation in tumor and blood samples of glioblastoma patients

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    Circulating biomarkers in blood may provide an interesting alternative to risky tissue biopsies in the diagnosis and follow-up of glioblastoma patients. We have assessed MGMT methylation status in blood and tissue samples from unresected glioblastoma patients who had been included in the randomized GENOM-009 trial. Paired blood and tissue samples were assessed by methylation-specific PCR (MSP) and pyrosequencing (PYR). After establishing the minimum PYR cut-off that could yield a significant difference in overall survival, we assessed the sensitivity, specificity, positive predictive value and negative predictive value (NPV) of the analyses. Methylation could be detected in cfDNA by both MSP and PYR but with low concordance with results in tissue. Sensitivity was low for both methods (31% and 38%, respectively), while specificity was higher for MSP in blood than for PYR in plasma (96% vs 76%) and NPV was similar (56 vs 57%). Concordance of results in tissue by MSP and PYR was 84.3% (P < 0.001) and correlated with outcome. We conclude that detection of cfDNA in the blood of glioblastoma patients can be an alternative when tumor tissue is not available but methods for the detection of cfDNA in blood must improve before it can replace analysis in tumor tissue

    First scientific observations with MEGARA at GTC

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    On June 25th 2017, the new intermediate-resolution optical IFU and MOS of the 10.4-m GTC had its first light. As part of the tests carried out to verify the performance of the instrument in its two modes (IFU and MOS) and 18 spectral setups (identical number of VPHs with resolutions R=6000-20000 from 0.36 to 1 micron) a number of astronomical objects were observed. These observations show that MEGARA@GTC is called to fill a niche of high-throughput, intermediateresolution IFU and MOS observations of extremely-faint narrow-lined objects. Lyman-α absorbers, star-forming dwarfs or even weak absorptions in stellar spectra in our Galaxy or in the Local Group can now be explored to a new level. Thus, the versatility of MEGARA in terms of observing modes and spectral resolution and coverage will allow GTC to go beyond current observational limits in either depth or precision for all these objects. The results to be presented in this talk clearly demonstrate the potential of MEGARA in this regard

    Substance Use and Psychological Distress in Mexican Adults during COVID-19 Pandemic: A Cross-Sectional Study

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    Objectives: This observational cross-sectional study examined changes in substance use during the coronavirus disease 2019 (COVID-19) pandemic in the Mexican population and evaluated whether depression or anxiety was associated with these new consumption patterns. Methods: An online survey was distributed to the general population. Participants were questioned about their demographics, situation during the COVID-19 pandemic, and substance consumption patterns. The Patient Health Questionnaire-9 for depression and the Coronavirus Anxiety Scale were used. Results: A total of 866 individuals completed the survey. The mean scores for the Patient Health Questionnaire-9 and Coronavirus Anxiety Scale were 8.89 &plusmn; 6.20 and 3.48 &plusmn; 3.22, respectively. The preferred substances were alcohol (19%), tobacco (16.5%), and marijuana (5.6%). Consumption of alcohol (p = 0.042) significantly increased during the pandemic and it was higher in women than in men (p = 0.040). Conclusions: Substance use patterns were affected by the pandemic, with an increase in the number of users and consumption rate, as well as the reported psychiatric symptoms
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