The decline in stroke hospitalization due to COVID-19 is unrelated to COVID-19 intensity.

BACKGROUND AND PURPOSE: During the coronavirus disease 2019 (COVID-19) pandemic many countries reported a decline in stroke volumes. The aim of this study was to analyze if the decline was related to the intensity of the COVID-19 pandemic. METHODS: The first pandemic year (1 March 2020 to 28 February 2021) overall and during the three COVID-19 waves were compared with the preceding year. Volumes of acute ischaemic stroke (AIS), subarachnoid hemorrhage, intracerebral hemorrhage and recanalization treatments (intravenous thrombolysis [IVT] and mechanical thrombectomy [MT]) were obtained from the National Register of Reimbursed Health Services. Door-to-needle time, onset-to-door time and National Institutes of Health Stroke Scale at admission were obtained from the Registry of Stroke Care Quality. RESULTS: During the pandemic year compared to the preceding year there were 26,453 versus 28,771 stroke admissions, representing an 8.8% decline (p < 0.001). The declines (-10%, -11%, -19%) appeared in COVID-19 waves (spring 2020, autumn 2020, winter 2021) except for an increase (2%) during summer 2020. Admissions for AIS declined by 10.2% (p < 0.001), whilst hemorrhagic stroke volumes were minimally decreased. The absolute volumes of IVT and MT decreased by 9.4% (p < 0.001) and 5.7% (p = 0.16), respectively. However, the proportions of ischaemic stroke patients receiving IVT (18% vs. 18%; p = 0.72) and MT (6% vs. 6%; p = 0.28) remained unchanged. CONCLUSIONS: There was a decline in stroke admissions, but such decline was not related to COVID-19 incidence. The frequency of use of recanalization procedures (IVT, MT) and times (onset-to-door time, door-to-needle time) in AIS were preserved in the Czech Republic during the first year of the pandemic.

Safety and Efficacy of Baseline Antiplatelet Treatment in Patients Undergoing Mechanical Thrombectomy for Ischemic Stroke: Antiplatelets Before Mechanical Thrombectomy.

PURPOSE: To investigate the safety and efficacy of baseline antiplatelet treatment in patients with acute ischemic stroke (AIS) undergoing mechanical thrombectomy (MT). MATERIALS AND METHODS: Baseline use of antiplatelet medication before MT for (AIS) may provide benefit on reperfusion and clinical outcome but could also carry an increased risk of intracranial hemorrhage (ICH). All consecutive patients with AIS and treated with MT with and without intravenous thrombolysis (IVT) between January 2012 and December 2019 in all centers performing MT nationwide were reviewed. Data were prospectively collected in national registries (eg, SITS-TBY and RES-Q). Primary outcome was functional independence (modified Rankin Scale 0-2) at 3 months; secondary outcome was ICH. RESULTS: Of the 4,351 patients who underwent MT, 1,750 (40%) and 666 (15%) were excluded owing to missing data from the functional independence and ICH outcome cohorts, respectively. In the functional independence cohort (n = 2,601), 771 (30%) patients received antiplatelets before MT. Favorable outcome did not differ in any antiplatelet, aspirin, and clopidogrel groups when compared with that in the no-antiplatelet group: odds ratio (OR), 1.00 (95% CI, 0.84-1.20); OR, 1.05 (95% CI, 0.86-1.27); and OR, 0.88 (95% CI, 0.55-1.41), respectively. In the ICH cohort (n = 3,685), 1095 (30%) patients received antiplatelets before MT. The rates of ICH did not increase in any treatment options (any antiplatelet, aspirin, clopidogrel, and dual antiplatelet groups) when compared with those in the no-antiplatelet group: OR, 1.03 (95% CI, 0.87-1.21); OR, 0.99 (95% CI, 0.83-1.18); OR, 1.10 (95% CI, 0.82-1.47); and OR, 1.43 (95% CI, 0.87-2.33), respectively. CONCLUSIONS: Antiplatelet monotherapy before MT did not improve functional independence or increase the risk of ICH.

The antitumoral activity of TLR7 ligands is corrupted by the microenvironment of pancreatic tumors.

Toll-like receptors (TLRs) are key players in the innate immune system. Recent studies have suggested that they may affect the growth of pancreatic cancer, a disease with no cure. Among them, TLR7 shows promise for therapy but may also promotes tumor growth. Thus, we aimed to clarify the therapeutic potential of TLR7 ligands in experimental pancreatic cancer models, to open the door for clinical applications. In vitro, we found that TLR7 ligands strongly inhibit the proliferation of both human and murine pancreatic cancer cells, compared with TLR2 agonists. Hence, TLR7 treatment alters cancer cells' cell cycle and induces cell death by apoptosis. In vivo, TLR7 agonist therapy significantly delays the growth of murine pancreatic tumors engrafted in immunodeficient mice. Remarkably, TLR7 ligands administration instead increases tumor growth and accelerates animal death when tumors are engrafted in immunocompetent models. Further investigations revealed that TLR7 agonists modulate the intratumoral content and phenotype of macrophages and that depleting such tumor-associated macrophages strongly hampers TLR7 agonist-induced tumor growth. Collectively, our findings shine a light on the duality of action of TLR7 agonists in experimental cancer models and call into question their use for pancreatic cancer therapy.

Treat COVID-19, but Not Only COVID-19: Stroke Matters as Well.

INTRODUCTION: During the COVID-19 pandemic, studies reported less number of hospitalizations for acute stroke and reduction in the use of recanalization treatments. This study analyzes nationwide data on stroke admissions and management in the Czech Republic during the first wave of the COVID-19 pandemic. METHODS: We compared the early COVID-19 pandemic (March-May 2020) with the pre-pandemic period (January-February 2020 and March-May 2019): (a) the National Register of Reimbursed Health Services provided volume of all admissions for subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH), and ischemic stroke (IS), and volume of recanalization treatments (intravenous thrombolysis [IVT] and mechanical thrombectomy [MT]); (b) Registry of Stroke Care Quality provided door-to-needle time (DNT), onset-to-door time (ODT), and stroke severity at admission (National Institutes of Health Stroke Scale, NIHSS) for IS. RESULTS: During the pandemic (March-May 2020), the peak number of COVID-19 patients treated in Czech hospitals was 39 per million. In March-May 2020 versus March-May 2019, hospital admissions decreased as follows: stroke overall by 14% (p < 0.001), IS by 14% (p < 0.001), SAH by 15% (p = 0.07), and ICH by 7% (p = 0.17). The mean age was 74 years versus 74 years (p = 0.33), and 52% versus 51% were men (p = 0.34). The volumes of IVT and MT decreased by 14% (p = 0.001) and 19% (p = 0.01), respectively. The proportions of all IS patients receiving IVT or MT remained unchanged, with, respectively, 17% versus 17% receiving IVT (p = 0.86) and 5% versus 5% receiving MT (p = 0.48). DNT and ODT were 24 versus 25 min (p = 0.58) and 168 versus 156 min (p = 0.23), respectively. NIHSS at admission did not differ (6 vs. 6; p = 0.54). CONCLUSION: Even with a low burden of COVID-19 during the first wave and no change in organization and logistics of stroke services, stroke admissions and volume of recanalization treatments decreased. Public health communication campaigns should encourage people to seek emergency medical care for stroke symptoms during the COVID-19 pandemic.

Mechanical Thrombectomy Quality Indicators Study in Czech Stroke Centers: Results of the METRICS Study.

BACKGROUND AND PURPOSE: Rigorous and regular evaluation of defined quality indicators is crucial for further improvement of both technical and clinical results after mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Following the recent international multi-society consensus quality indicators, we aimed to assess trend in these indicators on national level. MATERIAL AND METHODS: The prospective multicenter study (METRICS) was conducted in Czech Republic (CR) in year 2019. All participating centers collected technical and clinical data including defined quality indicators and results were subsequently compared with those from year 2016. RESULTS: In the 2019, 1375 MT were performed in the CR and 1178 (86%) patients (50.3% males, mean age 70.5 ± 13.0 years) were analyzed. Recanalization (TICI 2b-3) was achieved in 83.7% of patients and 46.2% of patients had good 3-month clinical outcome. Following time intervals were shortened in comparison to 2016: "hospital arrival - GP" (77 vs. 53 min; p<0.0001), "hospital arrival - maximal achieved recanalization" (122 vs. 93 min; p<0.0001), and "stroke onset - maximal achieved recanalization" (240 vs. 229 min; p p<0.0001). More patients with tandem occlusion were treated in 2019 (7.8 vs. 16.5%; p<0.0001) and more secondary transports were in 2019 (31.3 vs. 37.8%; p=0.002). No difference was found in 3-month clinical outcome and in the rate of periprocedural complications. Results of the METRICS study met all criteria of multi-society consensus quality indicators. CONCLUSION: Nationwide comparison between 2016 and 2019 showed improvement in the key time intervals, but without better overall clinical outcomes after MT.

Warfarin loading dose guided by pharmacogenetics is effective and safe in cardioembolic stroke patients - a randomized, prospective study.

Warfarin treatment is commonly started with a fixed loading dose that might be associated with an increased risk of bleeding. An individual maintenance dose can then be estimated based on a pharmacogenetic algorithm. Starting treatment with the estimated dose implies a longer time to reach the therapeutic range. Our goal was to compare the safety and efficacy of initiating warfarin treatment with a loading dose guided by pharmacogenetics versus a maintenance dose. The primary endpoint was time in the therapeutic range (TTR) in the first 10 days of treatment. Secondary endpoints were time to the first international normalized ratio (INR) in therapeutic range (2.0-3.0) and occurrence of serious adverse events. Consenting cardioembolic stroke patients were genotyped for CYP2C9 (cytochrome P450 2C9 gene) and VKORC1 (vitamin K epoxide reductase complex, subunit 1 gene) polymorphisms and a maintenance warfarin dose was estimated. Patients were randomized into two groups. The loading dose group (LDG) patients received twice the estimated dose in the first 2 days of treatment. The maintenance dose group (MDG) patients received the estimated dose directly from day one. The TTR in the first 10 days was significantly higher in the LDG than in the MDG (50.5% vs. 38.3%, p = 0.003). The time to the first INR in this range was significantly shorter in the LDG (5.24 vs. 7.3 days). There were no significant differences in the INR above this range or serious adverse events. Warfarin loading dose guided by pharmacogenetics after recent cardioembolic stroke improved the efficacy of warfarin initiation without increasing the risk of adverse events.

Impact of CYP2C19 Polymorphisms on Clinical Outcomes and Antiplatelet Potency of Clopidogrel in Caucasian Poststroke Survivors.

BACKGROUND: Variable response after clopidogrel is well documented and may affect major adverse clinical events after stroke. Impact of CYP2C19 genetic polymorphisms is an established marker linked to variable response after clopidogrel. However, the association of certain genetic polymorphisms with prediction of major adverse clinical events following stroke still remains controversial, especially in Caucasians. STUDY QUESTION: The primary aim was to evaluate the impact of CYP2C19 allele *2 in heterozygote form on major adverse clinical events in Caucasian poststroke survivors treated with clopidogrel. The secondary aim was to analyze the potential link between CYP2C19 genetic polymorphism and variable response after clopidogrel. STUDY DESIGN: One hundred thirty patients of Caucasian origin following documented ischemic stroke were included. Platelet reactivity was assessed by light transmittance aggregometry (LTA) and matched with various CYP2C19 loss-of-function genetic polymorphisms and major adverse clinical events (composite of vascular deaths, stroke/transient ischemic attack, and myocardial infarction). RESULTS: Over the mean follow-up of 14.9 months, 19 patients experienced major adverse clinical events. The risk of major adverse clinical events was nearly 3-fold in loss-of-function allele carriers (hazard ratio = 2.904; 95% confidence interval, 1.083-7.786; P = 0.013), whereas the risk of ischemic stroke or transient ischemic attack alone was also higher (hazard ratio = 3.170; 95% confidence interval, 1.281-7.849; P = 0.034). Platelet activity was strongly associated with allele *2 status (rs = 0.21, P = 0.016) but not with other genetic polymorphisms. Carriers of allele*2 exhibited lower platelet response to adenosine diphosphate-mean LTA (30.1% vs. 42.0%; P = 0.017). There were no significant differences in LTA results with other agonists. Strong association of increase in adenosine diphosphate-induced aggregation with diabetes mellitus (rs = 0.20, P = 0.023), increasing age (rs = 0.23, P = 0.008), and conversely diminishing over increased weight (rs = 0.23, P = 0.009) was also detected. The carriers of other gene allele variants lack uniformed impact on variable response after clopidogrel. CONCLUSIONS: Even heterozygous CYP2C19*2 allele carriers among Caucasian patients after ischemic stroke had a higher risk of major adverse clinical events. The LTA, however, did not predict major adverse clinical events. The exact clinical utility of these findings is still uncertain and requires large outcome-driven randomized trial in Caucasians for proof of concept.

Effects of Sunitinib and Other Kinase Inhibitors on Cells Harboring a PDGFRB Mutation Associated with Infantile Myofibromatosis.

Infantile myofibromatosis represents one of the most common proliferative fibrous tumors of infancy and childhood. More effective treatment is needed for drug-resistant patients, and targeted therapy using specific protein kinase inhibitors could be a promising strategy. To date, several studies have confirmed a connection between the p.R561C mutation in gene encoding platelet-derived growth factor receptor beta (PDGFR-beta) and the development of infantile myofibromatosis. This study aimed to analyze the phosphorylation of important kinases in the NSTS-47 cell line derived from a tumor of a boy with infantile myofibromatosis who harbored the p.R561C mutation in PDGFR-beta. The second aim of this study was to investigate the effects of selected protein kinase inhibitors on cell signaling and the proliferative activity of NSTS-47 cells. We confirmed that this tumor cell line showed very high phosphorylation levels of PDGFR-beta, extracellular signal-regulated kinases (ERK) 1/2 and several other protein kinases. We also observed that PDGFR-beta phosphorylation in tumor cells is reduced by the receptor tyrosine kinase inhibitor sunitinib. In contrast, MAPK/ERK kinases (MEK) 1/2 and ERK1/2 kinases remained constitutively phosphorylated after treatment with sunitinib and other relevant protein kinase inhibitors. Our study showed that sunitinib is a very promising agent that affects the proliferation of tumor cells with a p.R561C mutation in PDGFR-beta.

Much more than you expected: The non-DHFR-mediated effects of methotrexate.

BACKGROUND: For decades, methotrexate (MTX; amethopterin) has been known as an antifolate inhibitor of dihydrofolate reductase (DHFR), and it is widely used for the treatment of various malignancies and autoimmune diseases. Although the inclusion of MTX in various therapeutic regimens is based on its ability to inhibit DHFR and consequently to suppress the synthesis of pyrimidine and purine precursors, recent studies have shown that MTX is also able to target other intracellular pathways that are independent of folate metabolism. SCOPE OF REVIEW: The main aim of this review is to summarize the most important, up-to-date findings of studies regarding the non-DHFR-mediated mechanisms of MTX action. MAJOR CONCLUSIONS: The effectiveness of MTX is undoubtedly caused by its capability to affect various intracellular pathways at many levels. Although the most important therapeutic mechanism of MTX is strongly based on the inhibition of DHFR, many other effects of this compound have been described and new studies bring new insights into the pharmacology of MTX every year. GENERAL SIGNIFICANCE: Identification of these new targets for MTX is especially important for a better understanding of MTX action in new protocols of combination therapy.

Inactivation kinetics of invertase in honey and honey-glucose syrup formulations: effects of temperature and water activity.

BACKGROUND: The high viscosity and stickiness of honey in its natural state causes handling difficulties, therefore the demand for honey powder is continuously increasing. Powder preparation has to be performed gently because of the thermo- and oxidation- sensitive nature of honey. The aim of this study was to determine the degradation of invertase during drying as an indirect measure of the retention of valuable honey nutrients. RESULTS: The reaction kinetics were estimated in polyfloral honey and honey-glucose syrup (GS) formulation and the impact of temperature (40-70°C) and water activity (aw 0.23-0.81) was established. The honey-GS formulation (55:45 w/w) was intended for the preparation of high-grade honey powders using the vacuum-drying method. Invertase inactivation at temperatures below 60°C followed first-order kinetics. At 60°C high dilution (aw 0.81) and at 70°C, heterogeneous inactivation behaviour was observed. The best fit of invertase heterogeneous inactivation kinetic was achieved with the Cerf two-fraction model. The GS addition showed a stabilizing effect on invertase during thermal degradation. CONCLUSION: The data on invertase inactivation gathered here can be utilized to select optimal parameters for honey vacuum-drying and other thermal processes in order to achieve maximum invertase retention. © 2016 Society of Chemical Industry.

Non-DHFR-mediated effects of methotrexate in osteosarcoma cell lines: epigenetic alterations and enhanced cell differentiation.

BACKGROUND: Methotrexate is an important chemotherapeutic drug widely known as an inhibitor of dihydrofolate reductase (DHFR) which inhibits the reduction of folic acid. DHFR-mediated effects are apparently responsible for its primary antineoplastic action. However, other non-DHFR-mediated effects of methotrexate have been recently discovered, which might be very useful in the development of new strategies for the treatment of pediatric malignancies. The principal goal of this study was to analyze the possible impact of clinically achievable methotrexate levels on cell proliferation, mechanisms of epigenetic regulation (DNA methylation and histone acetylation), induced differentiation and the expression of differentiation-related genes in six osteosarcoma cell lines. METHODS: The Saos-2 reference cell line and five other patient-derived osteosarcoma cell lines were chosen for this study. The MTT assay was used to assess cell proliferation, DNA methylation and histone acetylation were detected using ELISA, and western blotting was used for a detailed analysis of histone acetylation. The expression of differentiation-related genes was quantified using RT-qPCR and the course of cell differentiation was evaluated using Alizarin Red S staining, which detects the level of extracellular matrix mineralization. RESULTS: Methotrexate significantly decreased the proliferation of Saos-2 cells exclusively, suggesting that this reference cell line was sensitive to the DHFR-mediated effects of methotrexate. In contrast, other results indicated non-DHFR-mediated effects in patient-derived cell lines. Methotrexate-induced DNA demethylation was detected in almost all of them; methotrexate was able to lower the level of 5-methylcytosine in treated cells, and this effect was similar to the effect of 5-aza-2'-deoxycytidine. Furthermore, methotrexate increased the level of acetylated histone H3 in the OSA-06 cell line. Methotrexate also enhanced all-trans retinoic acid-induced cell differentiation in three patient-derived osteosarcoma cell lines, and the modulation of expression of the differentiation-related genes was also shown. CONCLUSIONS: Overall non-DHFR-mediated effects of methotrexate were detected in the patient-derived osteosarcoma cell lines. Methotrexate acts as an epigenetic modifier and has a potential impact on cell differentiation and the expression of related genes. Furthermore, the combination of methotrexate and all-trans retinoic acid can be effective as a differentiation therapy for osteosarcoma.

The bleeding risk during warfarin therapy is associated with the number of variant alleles of CYP2C9 and VKORC1 genes.

BACKGROUND: Warfarin is commonly used for the treatment and prevention of arterial and venous thromboembolism but its use is hindered by the risk of bleeding. The main reason for this risk is a narrow therapeutic index and a wide response variability after warfarin treatment. These shortcomings affect clinical outcomes including bleeding complications and may be associated with variant polymorphisms in the CYP2C9 and VKORC1 genes. AIM: It was the aim of this study to assess the impact of the total variant allele count of CYP2C9 and VKORC1 genes on bleeding related to warfarin treatment. METHODS: In a retrospective cohort-design study, patients were genotyped for polymorphisms in genes CYP2C9 (*1, *2, *3) and VKORC1 (haplotype A, B). Extensive clinical data were obtained. Adjusted hazard ratios (HR) for the occurrence of major bleeding events (MBE) were counted separately for the induction and maintenance phases of warfarin therapy. RESULTS: Out of the 329 patients in our clinical database, 194 patients were eligible and included in the analysis. MBE occurred in 51 patients (26.3%) during a mean follow-up of 26 months: 6 patients (11.8%) experienced early MBE during warfarin initiation, and 45 MBE occurred during the maintenance phase. The adjusted HR for MBE risk for patients with any CYP2C9 variant allele was 1.962 [95% confidence interval (CI) 1.08-3.56, p = 0.027]; for the VKORC1 AA haplotype, HR was 1.841 (95% CI 0.97-3.48, p = 0.06), while for 3 variant allele carriers of both genes, HR was 4.34 (95% CI 1.95-9.65, p < 0.001). Despite the insignificant association of the VKORC1 genotype with bleeding in our study, we have noted a warfarin dose-dependent effect with risk significance ascending: CYP2C9 *1/*1 + VKORC1 B/B < CYP2C9 *1/*1 + VKORC1 A/B < CYP2C9 *1/*2 + VKORC1 B/B. CONCLUSION: Patients who are carriers of 3 variant alleles of the genes CYP2C9 and VKORC1 exhibited a significantly higher risk of MBE during the initiation and maintenance phases of warfarin therapy. Vigilant and careful management of patients with a higher variant allele count, including switching to newer anticoagulants, could be considered in this high-risk cohort.

Shifts in intra-annual growth dynamics drive a decline in productivity of temperate trees in Central European forest under warmer climate.

Climate change shifts tree growth phenology and dynamics in temperate forests. However, there is still little information on how warming climate changes intra-annual growth patterns and how these changes affect the productivity and carbon uptake of temperate trees. To address this knowledge gap, we used high-precision growth data from automatic dendrometers to quantify the impacts of unusually warm weather in 2022 (hot year) on growth phenology, dynamics and aboveground biomass (AGB) production in eight common temperate species (both conifers and broadleaved) in the Czech Republic. Mixed-effect models were used to investigate inter-annual changes in the start, end, and length of the growing season and intra-annual growth dynamics. We also modelled how changes in growth phenology, growth rates, and tree size affected yearly AGB production of individual trees. In the hot year, the growth started 5 days earlier, peaked 22 days earlier and ended 20 days earlier than in the climatically normal year, resulting in a shorter growing season with fewer growing days. AGB production decreased 36 % in the hot year, mainly due to fewer growing days and lower maximum growth rates, but with significant variation among tested species. The decline in AGB production in the hot year was most significant in the most productive species, which were also the species with the greatest reduction in the number of growing days. Tree size strongly enhanced AGB production, but its effect did not change with climate variation. Our findings suggest that climate change is likely to advance but also shorten the growing season of temperate trees, resulting in lower biomass production and carbon uptake. The results also indicate that the fast-growing and highly productive temperate tree species will have their growth reduced most by climate change, which will increasingly limit their high carbon sequestration potential.

Endovascular treatment for acute ischemic stroke in patients with tandem lesion in the anterior circulation: analysis from the METRICS study.

BACKGROUND: Acute ischemic stroke (AIS) due to anterior circulation tandem lesion (TL) remains a technical and clinical challenge for endovascular treatment (EVT). Conflicting results from observational studies and missing evidence from the randomized trials led us to report a recent real-world multicenter clinical experience and evaluate possible predictors of good outcome after EVT. METHODS: We analyzed all AIS patients with TL enrolled in the prospective national study METRICS (Mechanical Thrombectomy Quality Indicators Study in Czech Stroke Centers). A good 3-month clinical outcome was scored as 0-2 points in modified Rankin Scale (mRS), achieved recanalization using the Thrombolysis In Cerebral Infarction (TICI) scale and symptomatic intracerebral hemorrhage (sICH) according to the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) criteria. RESULTS: Of 1178 patients enrolled in METRICS, 194 (19.2%) (59.8% males, mean age 68.7±11.5 years) were treated for TL. They did not differ in mRS 0-2 (48.7% vs 46.7%; p=0.616), mortality (17.3% vs 22.7%; p=0.103) and sICH (4.7% vs 5.1%; p=0.809) from those with single occlusion (SO). More TL patients with prior intravenous thrombolysis (IVT) reached TICI 3 (70.3% vs 50.8%; p=0.012) and mRS 0-2 (55.4% vs 34.4%; p=0.007) than those without IVT. No difference was found in the rate of sICH (6.2% vs 1.6%; p=0.276). Multivariate logistic regression analysis showed prior IVT as a predictor of mRS 0-2 after adjustment for potential confounders (OR 3.818, 95% CI 1.614 to 9.030, p=0.002). CONCLUSION: Patients with TL did not differ from those with SO in outcomes after EVT. TL patients with prior IVT had more complete recanalization and mRS 0-2 and IVT was found to be a predictor of good outcome after EVT.

Screening and Risk Stratification Strategy Reduced Decompression Sickness Occurrence in Divers With Patent Foramen Ovale.

OBJECTIVES: This paper sought to evaluate the occurrence of decompression sickness (DCS) after the application of a patent foramen ovale (PFO) screening and risk stratification strategy. BACKGROUND: PFO is associated with an increased risk of DCS. Recently, transcatheter closure was reported to reduce DCS occurrence in divers with a high-grade shunt. However, to date, there are no data regarding the effectiveness of any PFO screening and risk stratification strategy for divers. METHODS: A total of 829 consecutive divers (age 35.4 ± 10.0 years, 81.5% men) were screened for PFO by means of transcranial color-coded sonography in the DIVE-PFO (Decompression Illness Prevention in Divers with a Patent Foramen Ovale) registry. Divers with a high-grade PFO were offered either catheter-based PFO closure (the closure group) or advised conservative diving (high grades). Divers with a low-grade shunt were advised conservative diving (low grades), whereas those with no PFO continued unrestricted diving (controls). A telephone follow-up was performed. To study the effect of the screening and risk stratification strategy, DCS occurrence before enrollment and during the follow-up was compared. RESULTS: Follow-up was available for 748 (90%) divers. Seven hundred and 2 divers continued diving and were included in the analysis (mean follow-up 6.5 ± 3.5 years). The DCS incidence decreased significantly in all groups, except the controls. During follow-up, there were no DCS events in the closure group; DCS incidence was similar to the controls in the low-grade group (HR: 3.965; 95% CI: 0.558-28.18; P = 0.169) but remained higher in the high-grade group (HR: 26.170; 95% CI: 5.797-118.160; P < 0.0001). CONCLUSIONS: The screening and risk stratification strategy using transcranial color-coded sonography was associated with a decrease in DCS occurrence in divers with PFO. Catheter-based PFO closure was associated with a DCS occurrence similar to the controls; the conservative strategy had a similar effect in the low-grade group, but in the high-grade group the DCS incidence remained higher than in all other groups.

Ultrashort Door-to-Needle Time for Intravenous Thrombolysis Is Safer and Improves Outcome in the Czech Republic: Nationwide Study 2004 to 2019.

Background The benefit of intravenous thrombolysis is time dependent. It remains unclear, however, whether dramatic shortening of door-to-needle time (DNT) among different types of hospitals nationwide does not compromise safety and still improves outcome. Methods and Results Multifaceted intervention to shorten DNT was introduced at a national level, and prospectively collected data from a registry between 2004 and 2019 were analyzed. Generalized estimating equation was used to identify the association between DNT and outcomes independently from prespecified baseline variables. The primary outcome was modified Rankin score 0 to 1 at 3 months, and secondary outcomes were parenchymal hemorrhage/intracerebral hemorrhage (ICH), any ICH, and death. Of 31 316 patients treated with intravenous thrombolysis alone, 18 861 (60%) had available data: age 70±13 years, National Institutes of Health Stroke Scale at baseline (median, 8; interquartile range, 5-14), and 45% men. DNT groups 0 to 20 minutes, 21 to 40 minutes, 41 to 60 minutes, and >60 minutes had 3536 (19%), 5333 (28%), 4856 (26%), and 5136 (27%) patients. National median DNT dropped from 74 minutes in 2004 to 22 minutes in 2019. Shorter DNT had proportional benefit: it increased the odds of achieving modified Rankin score 0 to 1 and decreased the odds of parenchymal hemorrhage/ICH, any ICH, and mortality. Patients with DNT ≤20 minutes, 21 to 40 minutes, and 41 to 60 minutes as compared with DNT >60 minutes had adjusted odds ratios for modified Rankin score 0 to 1 of the following: 1.30 (95% CI, 1.12-1.51), 1.33 (95% CI, 1.15-1.54), and 1.15 (95% CI, 1.02-1.29), and for parenchymal hemorrhage/ICH: 0.57 (95% CI, 0.45-0.71), 0.76 (95% CI, 0.61-0.94), 0.83 (95% CI, 0.70-0.99), respectively. Conclusions Ultrashort initiation of thrombolysis is feasible, improves outcome, and makes treatments safer because of fewer intracerebral hemorrhages. Stroke management should be optimized to initiate thrombolysis as soon as possible optimally within 20 minutes from arrival to a hospital.

Transcription factor c-Myb: novel prognostic factor in osteosarcoma.

The transcription factor c-Myb is an oncoprotein promoting cell proliferation and survival when aberrantly activated/expressed, thus contributing to malignant transformation. Overexpression of c-Myb has been found in leukemias, breast, colon and adenoid cystic carcinoma. Recent studies revealed its expression also in osteosarcoma cell lines and suggested its functional importance during bone development. However, the relevance of c-Myb in control of osteosarcoma progression remains unknown. A retrospective clinical study was carried out to assess a relationship between c-Myb expression in archival osteosarcoma tissues and prognosis in a cohort of high-grade osteosarcoma patients. In addition, MYB was depleted in metastatic osteosarcoma cell lines SAOS-2 LM5 and 143B and their growth, chemosensitivity, migration and metastatic activity were determined. Immunohistochemical analysis revealed that high c-Myb expression was significantly associated with poor overall survival in the cohort and metastatic progression in young patients. Increased level of c-Myb was detected in metastatic osteosarcoma cell lines and its depletion suppressed their growth, colony-forming capacity, migration and chemoresistance in vitro in a cell line-dependent manner. MYB knock-out resulted in reduced metastatic activity of both SAOS-2 LM5 and 143B cell lines in immunodeficient mice. Transcriptomic analysis revealed the c-Myb-driven functional programs enriched for genes involved in the regulation of cell growth, stress response, cell adhesion and cell differentiation/morphogenesis. Wnt signaling pathway was identified as c-Myb target in osteosarcoma cells. Taken together, we identified c-Myb as a negative prognostic factor in osteosarcoma and showed its involvement in the regulation of osteosarcoma cell growth, chemosensitivity, migration and metastatic activity.

Lipidomic Analysis to Assess Oxidative Stress in Acute Coronary Syndrome and Acute Stroke Patients.

Alterations in lipid metabolism mediated by oxidative stress play a key role in the process of atherosclerosis and superimposed thrombosis; these can lead to acute coronary syndrome (ACS) and acute ischemic stroke (AIS). Multiple studies have shown that the formation of atheromatous lesions is initiated by oxidation of low-density lipoproteins incorporated into the intima of the vessel wall. Here, we studied lipids in plasma samples from three cohorts: 61 patients with ACS (group A), 49 patients with AIS (group D), and 82 controls (group K). Untargeted lipidomics based on high-performance liquid chromatography coupled to mass spectrometry (UHPLC-HRMS) was employed to obtain comprehensive information on whether relationships exist between these patient categories based on lipid patterns. In addition, malondialdehyde (MDA) as a standard marker of oxidative stress was monitored. The most characteristic lipids in group K were fatty acyls of hydroxyfatty acids (FAHFAs). As expected, MDA concentrations were the lowest in group K. Our findings can better explain ongoing pathologies, both acute and chronic, with the potential for future diagnosis and treatment.

Tryptophan Metabolism, Inflammation, and Oxidative Stress in Patients with Neurovascular Disease.

Atherosclerosis is a leading cause of major vascular events, myocardial infarction, and ischemic stroke. Tryptophan (TRP) catabolism was recognized as an important player in inflammation and immune response having together with oxidative stress (OS) significant effects on each phase of atherosclerosis. The aim of the study is to analyze the relationship of plasma levels of TRP metabolites, inflammation, and OS in patients with neurovascular diseases (acute ischemic stroke (AIS), significant carotid artery stenosis (SCAS)) and in healthy controls. Blood samples were collected from 43 patients (25 with SCAS, 18 with AIS) and from 25 healthy controls. The concentrations of twelve TRP metabolites, riboflavin, neopterin (NEO, marker of inflammation), and malondialdehyde (MDA, marker of OS) were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Concentrations of seven TRP metabolites (TRP, kynurenine (KYN), 3-hydroxykynurenine (3-HK), 3-hydroxyanthranilic acid (3-HAA), anthranilic acid (AA), melatonin (MEL), tryptamine (TA)), NEO, and MDA were significantly different in the studied groups. Significantly lower concentrations of TRP, KYN, 3-HAA, MEL, TA, and higher MDA concentrations were found in AIS compared to SCAS patients. MDA concentration was higher in both AIS and SCAS group (p < 0.001, p = 0.004, respectively) compared to controls, NEO concentration was enhanced (p < 0.003) in AIS. MDA did not directly correlate with TRP metabolites in the study groups, except for 1) a negative correlation with kynurenine acid and 2) the activity of kynurenine aminotransferase in AIS patients (r = -0.552, p = 0.018; r = -0.504, p = 0.033, respectively). In summary, TRP metabolism is clearly more deregulated in AIS compared to SCAS patients; the effect of TRP metabolites on OS should be further elucidated.

Resprouting trees drive understory vegetation dynamics following logging in a temperate forest.

Removal of canopy trees by logging causes shifts in herbaceous diversity and increases invasibility of the forest understory. However, disturbed (cut) trees of many species do not die but resprout from remaining parts. Because sprouts develop vigorously immediately after disturbances, we hypothesized that sprouts of logged trees offset the changes in species richness and invasibility of the herbaceous layer by eliminating the rise in the resource availability during the time before regeneration from seeds develops. To test this, we analyzed data on herbaceous vegetation and sprout biomass collected in a broadleaved temperate forest in the Czech Republic before and for 6 years after logging. Sprouts that were produced by most of the stumps of logged trees offset large rises in species richness and cover of herbaceous plants and the resource availability that followed logging, but they affected the alien plants more significantly than the native plants. The sprouting canopy effectually eliminated most of the alien species that colonized the forest following a logging event. These findings indicate that in forests dominated by tree species with resprouting ability, sprouts drive the early post-disturbance dynamics of the herbaceous layer. By offsetting the post-disturbance vegetation shifts, resprouting supports forest resilience.