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Background and Purpose: The efficiency of prehospital care chain response and the adequacy of hospital resources are challenged amid the coronavirus disease 2019 (COVID-19) outbreak, with suspected consequences for patients with ischemic stroke eligible for mechanical thrombectomy (MT). Methods: We conducted a prospective national-level data collection of patients treated with MT, ranging 45 days across epidemic containment measures instatement, and of patients treated during the same calendar period in 2019. The primary end point was the variation of patients receiving MT during the epidemic period. Secondary end points included care delays between onset, imaging, and groin puncture. To analyze the primary end point, we used a Poisson regression model. We then analyzed the correlation between the number of MTs and the number of COVID-19 cases hospitalizations, using the Pearson correlation coefficient (compared with the null value). Results: A total of 1513 patients were included at 32 centers, in all French administrative regions. There was a 21% significant decrease (0.79; [95%CI, 0.76–0.82]; P <0.001) in MT case volumes during the epidemic period, and a significant increase in delays between imaging and groin puncture, overall (mean 144.9±SD 86.8 minutes versus 126.2±70.9; P <0.001 in 2019) and in transferred patients (mean 182.6±SD 82.0 minutes versus 153.25±67; P <0.001). After the instatement of strict epidemic mitigation measures, there was a significant negative correlation between the number of hospitalizations for COVID and the number of MT cases ( R 2 −0.51; P =0.04). Patients treated during the COVID outbreak were less likely to receive intravenous thrombolysis and to have unwitnessed strokes (both P <0.05). Conclusions: Our study showed a significant decrease in patients treated with MTs during the first stages of the COVID epidemic in France and alarming indicators of lengthened care delays. These findings prompt immediate consideration of local and regional stroke networks preparedness in the varying contexts of COVID-19 pandemic evolution.

Background and Purpose: Acute ischemic stroke and large vessel occlusion can be concurrent with the coronavirus disease 2019 (COVID-19) infection. Outcomes after mechanical thrombectomy (MT) for large vessel occlusion in patients with COVID-19 are substantially unknown. Our aim was to study early outcomes after MT in patients with COVID-19. Methods: Multicenter, European, cohort study involving 34 stroke centers in France, Italy, Spain, and Belgium. Data were collected between March 1, 2020 and May 5, 2020. Consecutive laboratory-confirmed COVID-19 cases with large vessel occlusion, who were treated with MT, were included. Primary investigated outcome: 30-day mortality. Secondary outcomes: early neurological improvement (National Institutes of Health Stroke Scale improvement ≥8 points or 24 hours National Institutes of Health Stroke Scale 0–1), successful reperfusion (modified Thrombolysis in Cerebral Infarction grade ≥2b), and symptomatic intracranial hemorrhage. Results: We evaluated 93 patients with COVID-19 with large vessel occlusion who underwent MT (median age, 71 years [interquartile range, 59–79]; 63 men [67.7%]). Median pretreatment National Institutes of Health Stroke Scale and Alberta Stroke Program Early Computed Tomography score were 17 (interquartile range, 11–21) and 8 (interquartile range, 7–9), respectively. Anterior circulation acute ischemic stroke represented 93.5% of cases. The rate modified Thrombolysis in Cerebral Infarction 2b to 3 was 79.6% (74 patients [95% CI, 71.3–87.8]). Thirty-day mortality was 29% (27 patients [95% CI, 20–39.4]). Early neurological improvement was 19.5% (17 patients [95% CI, 11.8–29.5]), and symptomatic intracranial hemorrhage was 5.4% (5 patients [95% CI, 1.7–12.1]). Patients who died at 30 days exhibited significantly lower lymphocyte count, higher levels of aspartate, and LDH (lactate dehydrogenase). After adjustment for age, initial National Institutes of Health Stroke Scale, Alberta Stroke Program Early Computed Tomography score, and successful reperfusion, these biological markers remained associated with increased odds of 30-day mortality (adjusted odds ratio of 2.70 [95% CI, 1.21–5.98] per SD-log decrease in lymphocyte count, 2.66 [95% CI, 1.22–5.77] per SD-log increase in aspartate, and 4.30 [95% CI, 1.43–12.91] per SD-log increase in LDH). Conclusions: The 29% rate of 30-day mortality after MT among patients with COVID-19 is not negligible. Abnormalities of lymphocyte count, LDH and aspartate may depict a patient’s profiles with poorer outcomes after MT. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04406090.

Mercury (Hg) enrichments in sediments are increasingly used as tracer for distal volcanism in deep‐time investigations. The impact of changes in organic‐matter deposition and preservation on sedimentary Hg sequestration is, however, poorly understood. In this study, we evaluate the potential role of intense weathering and postdepositional organic‐matter degradation on the Hg/TOC proxy in sediments. For this, we investigate weathering profiles in organic‐rich sediments from lowermost Toarcian sediments (T‐OAE; Lafarge cement quarry, France) and organic‐rich deposits from the uppermost Cenomanian‐lowermost Turonian Bonarelli level (OAE2; Furlo and Monte Velo, Italy; Manilva and El Chorro, Spain). The comparison of Hg data along weathering profiles in lowermost Toarcian sediments indicates that recent intense oxidation of the originally organic‐rich deposits has removed up to 89% of the Hg signal. The organic‐rich sediments of the Furlo and Manilva sections are characterized by lower Hg/total organic carbon (TOC) ratios, which suggest important Hg scavenging by organic matter (OM) deposition. At the opposite, in equivalent successions, three significant positive Hg/TOC excursions persist at El Chorro and Monte Velo. These samples exhibit low Hydrogen Index (HI) values, which plot in the field of type‐III OM. This resulted from postdepositional degradation of marine OM type II to type III, which largely modified the amount and the quality of OM. Consequently, the recorded Hg/TOC ratios do not reflect original Hg drawdown but postdepositional oxidation, suggesting that extreme care is needed in the evaluation of the history of OM preservation when using Hg as a proxy for volcanic activity.

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The breakup of Pangea and onset of growth of the Pacific plate led to several paleoenvironmental feedbacks, which radically affected paleoclimate and ocean chemistry during the Jurassic. Overall, this period was characterized by intense volcanic degassing from large igneous provinces and circum-Panthalassan arcs, new oceanic circulation patterns, and changes in heat and humidity transports affecting continental weathering. Few studies, however, have attempted to unravel the global interactions linking these processes over the long-term. In this paper, we address this question by documenting the global changes in continental drainage and surface oceanic circulation for the whole Jurassic period. For this purpose, we present 53 new neodymium isotope values (ε Nd(t)) measured on well-dated fossil fish teeth, ichthyosaur bones, phosphatized nodules, phosphatized ooids, and clastic sediments from Europe, western Russia, and North America. Combined with an extensive compilation of published ε Nd(t) data, our results show that the continental sources of Nd were very heterogeneous across the world. Volcanic inputs from a Jurassic equivalent of the modern Pacific Ring of Fire contributed to radiogenic ε Nd(t) values (− 4 ε-units) in the Panthalassa Ocean. For the Tethyan Ocean, the average surface seawater signal was less radiogenic in the equatorial region (− 6.3), and gradually lower toward the epicontinental peri-Tethyan (− 7.

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Intracranial hemorrhage is one of the most feared complications following brain infarct. Ischemic tissues have a natural tendency to bleed. Moreover, the first recanalization trials using intravenous thrombolysis have shown an increase in mild to severe intracranial hemorrhage. Symptomatic intracerebral hemorrhage is strongly associated with poor outcomes and is an important factor in recanalization decisions. Stroke physicians have to weigh the potential benefit of recanalization therapies, first, with different risks of intracranial hemorrhage described in randomized controlled trials, and second with numerous risk markers that have been found to be associated with intracranial hemorrhage in retrospective series. These decisions have become quite complex with different intravenous thrombolytics and mechanical thrombectomy. This review aims to outline some elements of the pathophysiological mechanisms and classifications, describe most of the risk factors identified for each reperfusion therapy, and finally suggest future research directions that could help physicians dealing with these complications.