Preliminary Application of a Quantitative Collateral Assessment Method in Acute Ischemic Stroke Patients With Endovascular Treatments: A Single-Center Study

Objectives: To develop an efficient and quantitative assessment of collateral circulation on time maximum intensity projection CT angiography (tMIP CTA) in patients with acute ischemic stroke (AIS).Methods: Eighty-one AIS patients who underwent one-stop CTA-CT perfusion (CTP) from February 2016 to October 2020 were retrospectively reviewed. Single-phase CTA (sCTA) and tMIP CTA were developed from CTP data. Ischemic core (IC) volume, ischemic penumbra volume, and mismatch ratio were calculated. The Tan scale was used for the qualitative evaluation of collateral based on sCTA and tMIP CTA. Quantitative collateral circulation (CCq) parameters were calculated semi-automatically with software by the ratio of the vascular volume (V) on both hemispheres, including tMIP CTA VCCq and sCTA VCCq. Spearman correlation analysis was used to analyze the correlation of collateral-related parameters with final infarct volume (FIV). ROC and multivariable regression analysis were calculated to compare the significance of the above parameters in clinical outcome evaluation. The analysis time of the observers was also compared.Results: tMIP CTA VCCq (r = 0.61, p < 0.01), IC volume (r = 0.66, p < 0.01), Tan score on tMIP CTA (r = 0.52, p < 0.01) and mismatch ratio (r = 0.60, p < 0.01) showed moderate negative correlations with FIV. tMIP CTA VCCq showed the best prognostic value for clinical outcome (AUC = 0.93, p < 0.001), and was an independent predictive factor of clinical outcome (OR = 0.14, p = 0.009). There was no difference in analysis time of tMIP CTA VCCq among observers (p = 0.079).Conclusion: The quantitative evaluation of collateral circulation on tMIP CTA is associated with clinical outcomes in AIS patients with endovascular treatments.

Migrant Racialization on Twitter during a border and a pandemic crisis

This work examines how the outbreak of the COVID-19 pandemic reshaped the migration debate on Twitter. Through co-hashtag network analysis, time-frequency and content analysis, it shows that the pandemic was related with positive (humanitarian) and negative (threat) stances about migration. The positive side focused on the need to protect refugees stranded at camps in Greece from COVID-19. The negative focused on the Greek-Turkish land-border crisis (Evros crisis), using COVID-19 to reinforce migrants as racialized others. These findings fit the problematization of positive and negative migrant representations in the Global north as Eurocentric. In the case of camps, refugees fit well within the victim/helpless frame, justifying humanitarianism, this time on health grounds. Regarding the border crisis, refugees also fit the Eurocentric frame of violent/male/inferior other who could spread a deadly virus. Overall, COVID-19 intertwined with migration in Twitter debates, reinforcing the racialized, Eurocentric representational field on migrants from the Global south.

Sequence Analysis: Time Use Data (ATUS) in R

This preprint walks you through the steps on how to perform sequence analysis using ATUS data in R.

An Optical Probe for Real-Time Monitoring of Self-Replicator Emergence and Distinguishing between Replicators

Self-replicating systems play an important role in research on the synthesis and origin of life. Monitoring of these systems has mostly relied on techniques such as NMR or chromatography, which are limited in throughput and demanding when monitoring replication in real time. To circumvent these problems, we now developed a pattern-generating fluorescent molecular probe (an ID-probe) capable of discriminating replicators of different chemical composition and monitoring the process of replicator formation in real time, giving distinct signatures for starting materials, intermediates and final products. Optical monitoring of replicators dramatically reduces the analysis time and sample quantities compared to most currently used methods and opens the door for future high-throughput experimentation in protocell environments.

P11.04 Autonomy duration as analyzed by KPS≥70 cumulative time in patients with biopsy-only glioblastoma (BO-GBM). A sub-analysis of the Timone cohort

BACKGROUND Improvement or maintenance of autonomy is a crucial and understudied issue for glioblastoma (GBM) patients whose outcome is poor. Biopsy-only GBM (BO-GBM) is a situation where survival is short and independence is of particular importance. Our objective was to explore functional outcome in biopsy-only patients. MATERIAL AND METHODS A regional glioma SIRIC cohort was conducted at CHU Timone in 2014–2017 and we retrospectively reviewed the BO-GBM subgroup. We prospectively collected age, corticosteroid dose, tumoral surface, treatment allocated and completed, and survival outcome. Functional independence was analyzed as a cumulative time of Karnofsky performance status (KPS) ≥70 from the date of diagnosis until death. We analyzed potential factors associated to time with KPS ≥70. RESULTS Among 535 patients enrolled in the cohort, surgery was restricted to biopsy in 139 patients (BO-GBM). Mean tumoral surface measured on gadolinium-enhanced T1-weighted MRI was 1198mm2 (min: 65; max: 4515mm2). Mean steroid dose at diagnosis was 50mg prednisolone per day. Corticosteroid dose was ≥50mg prednisolone per day for 77 patients and <50mg per day for 56 patients. Fifty-four patients (39%) were referred to radiotherapy-temozolomide (RT-TMZ), 68 (49%) considered unfitted for RT received chemotherapy upfront only (CT-UF), and 17 patients (12%) were referred to palliative care only. Median overall survival (OS) was 7.5 months (95%CI: 6.0–9.2), 14.0 months (95%CI: 9.7–18.7) and 6.0 months (95%CI: 4.6–7.7) for BO-GBM, RT-TMZ and CT-UF respectively. At diagnosis, 81 (58.3%) patients presented with self-care capacity (KPS ≥ 70%). For these patients, median time of autonomy preservation was 7.6 months (95%CI: 6.1–9.0). Median time of autonomy preservation differed according to treatment modalities: it was 8.6 months (95%CI: 5.9–11.3) versus 6.3 months (95%CI: 2.9–9.7) for RT-TMZ versus CT-UF group respectively (p<0.001). In univariate analysis, time with KPS ≥ 70% was correlated with age (p=0.001), initial KPS (p<0.001), tumoral surface measured on gadolinium-enhanced T1-weighted MRI (p=0.03) and corticosteroid dose (p=0.001). In multivariate analysis, time with KPS≥70 was correlated with age (p=0.001) and KPS at diagnosis (p<0.001). CONCLUSION Patients with inoperable GBM referred to radiotherapy-temozolomide present a valuable duration of functional independence, although shorter in patients not referred to RT. Duration of functional independence could be considered in addition to PFS and OS for treatment evaluation in patients with GBM.