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The literature data show that thrombophilia and maternal dysfunction of thyroid gland during pregnancy are associated with an increased risk of miscarriage, placental abruption, hypertensive disorders and fetal growth retardation. It was shown that thyroid hormones and hypercoagulable states influence onto a leucocyte activity. The aim of this study has been to investigate maternal leucocytes changes and their correlation with frequency of fetal cells micronuclei in pregnant women with thrombophilia and hypothyroidism. The samples of blood and amniotic fluid were collected from healthy pregnant women and pregnant women with inherited thrombophilia and hypothyroidism (16 - 18 weeks of gestation). Hematological characteristics were determined by using standard hematological methods. The frequency of micronuclei was determined in fetal cells after amniocentesis by using standard cytogenetic methods. The results of this study showed significant higher levels of β-hCG, number of monocytes and eosinophils in blood of pregnant women with thrombophilia. A large number of eosinophils was documented in blood of pregnant women with hypothyroidism. Increased percentage distribution of eosinophils and basophils is shown in both investigated groups of pregnant women. The increased fetal cells micronuclei frequency and their correlation with percentage distribution of eosinophils and basophils were indicated in pregnant women with hypothyroidism. The obtained results suggest that an increased percentage of eosinophils and basophils in pregnant women with hypothyroidism contribute to a formation of micronuclei in fetal cells.

Background As much of the scope of neurointerventional practice falls outside data covered by existing randomized clinical trials, and, as a result, may have failed to enter into existing guidelines, an evidence‐based framework for guideline and standards development is needed. We establish an evidence‐based framework to guide all subsequent guidelines and brief practice updates produced by the Society of Vascular and Interventional Neurology (SVIN). Methods The SVIN formed the Guidelines and Practice Parameters committee to develop the structure and procedures for guidelines and brief practice updates. Results In this article, the Guidelines and Practice Parameters committee has outlined the process by which the guidelines will be created and approved by the SVIN. Additionally, the Guidelines and Practice Parameters committee has adopted the American College of Cardiology/American Heart Association framework of Class of Recommendation and Level of Evidence. A unique, additional separation of the Expert Opinion endorsement category has been developed when high‐quality evidence does not exist at the time of the publication. Conclusions The SVIN has developed an evidence‐based framework for all guideline statements and brief practice updates. The SVIN guidelines and brief practice updates will guide clinicians in the field of interventional neurology to improve and standardize patient care.

Introduction: Nurses and staff in Emergency Departments (ED) with low monthly case volumes have few opportunities to build confidence and solidify skills in acute stroke management. The Nursing-driven Acute Stroke Care (NAS-Care) study tested a workflow model with empowerment of ED bedside nurses, clear role assignments for team members, and standardized protocols including a predefined run sheet. Methods: Seven Texas hospitals participated in this prospective, multisite, baseline-controlled study as part of the Lone Star Stroke Research Consortium. After three months of blinded baseline data collection, the following interventions were implemented: NIHSS certification, nursing education including mock stroke codes, and a standardized flowsheet for code organization and documentation (run sheet). Participating nurses were surveyed before and after implementation of this process. Results: The study was completed at 6 hospitals, with 180 patients in the pre-intervention group and 267 in the post-intervention group. The study intervention was found to improve Door-to-ED provider and Door-to-CT metrics but not physician-dependent metrics, Door-to-Needle or Door-to-Provider times (Provencher et al, ISC 2020). Completed surveys were returned by 97 nurses (pre-intervention) and 57 nurses (post-intervention). There were significant increases in the following questions (10 point scale, p Conclusion: Standardized nurse-driven stroke protocols improved self-assessed knowledge and confidence for nurses in EDs utilizing telestroke, in addition to gains in staff-dependent stroke metrics.

Introduction and Purpose: Timely inter-facility transfer of thrombectomy-eligible patients is a mainstay of Stroke Systems of Care. We investigated transfer patterns among stroke certified hospitals in the Dallas-Fort Worth Metroplex (19 counties, 9,286 sq mi, >7.7 million people), by hospital network and stroke center status. Methods: In Feb 2020, all 44 North Central Texas Trauma Regional Advisory Council (NCTTRAC) hospitals identified network status, stroke designation and geographic location. Stroke Assessment and Large Vessel Occlusion (LVO) screening tool use was evaluated. The distance between the sending and receiving facility was calculated using GPS coordinates. If the closest Comprehensive Stroke Center (CSC) was not used, the average distance between the selected and the closest CSC was geospatially mapped via R statistical analysis software (Vienna, Austria) gmapsdistance package. Results: Of the 44 facilities, 6 were Acute Stroke Ready Hospitals (ASRHs), 27 were Primary Stroke Centers (PSCs), 11 were CSCs (Fig 1). Seventy-seven percent (n=34) were part of four hospital networks. All facilities used stroke assessment tools; 57% completed LVO screening. Seventeen percent of ASRHs (n=1) and 56% of PSCs (n=15) conducted inter-facility transfers. Sixty percent of non-network facilities transferred to the closest CSC. Of the remaining 40%, the average distance between the closest and the selected CSC was 1.5 miles (min max 0.2-2.9). Seventeen percent of network facilities transferred to the closest CSC. Among the remaining 83%, the average distance between the closest and the selected CSC was 4.1 miles (min-max 1-8). Conclusions: Non-network facility status increased the likelihood of transfer to the closest Comprehensive Stroke Center. Transfer distance variability among network facilities may contribute to delays in reperfusion therapy. Figure 1 . Transfer Patterns (in Blue) of Dallas Fort-Worth Metroplex Hospitals by Stroke Center Designation

Objective We aim to report intra-arterial thrombectomy transfer metrics for ischemic stroke patients that were transferred to hub hospitals for possible intra-arterial thrombectomy in multiple geographic regions throughout the state of Texas and to identify potential barriers and delays in the intra-arterial thrombectomy transfer process. Method We prospectively collected data from 8 participating Texas comprehensive stroke/thrombectomy capable centers from 7 major regions in the State of Texas. We collected baseline clinical and imaging data related to the pre-transfer evaluation, transfer metrics, and post-transfer clinical and imaging data. Results A total of 103 acute ischemic stroke patients suspected/confirmed to have large vessel occlusions between December 2016 to May 2019 that were transferred to hubs as possible intra-arterial thrombectomy candidates were enrolled. A total of 56 (54%) patients were sent from the spoke to the hub via ground ambulance with 47 (46%) patients traveling via air ambulance. The median spoke arrival to hub arrival time was 174 min, median spoke arrival to departure from spoke was 131 min, and median travel time was 39 min. The spoke arrival time to transfer initiation was 68 min. CT-perfusion obtained at the spoke and earlier initiation of transfer were statistically associated with shorter transfer times. Conclusion Transfer of intra-arterial thrombectomy patients in Texas may take over 4 h from spoke arrival to hub arrival. This time may be shortened by earlier transfer initiation and acceptance.

Introduction The flow diverter is a unique and important tool in the endovascular treatment of aneurysms. However, its use requires patients to be on dual antiplatelet therapy to prevent thromboembolic complications. The duration of dual antiplatelet therapy has not been standardized due to the relative risks of thromboembolic (too short) and hemorrhagic (too long) complications. The objective of this study is to compare the thromboembolic and hemorrhagic complication rates of patients on a shorter versus a longer course of dual antiplatelet therapy. Methods Patients undergoing flow diversion were prospectively enrolled in an institutional registry. After 3 to 6 months of dual antiplatelet therapy, patients were converted to aspirin 325 mg up to the 12 month period. Patients on dual antiplatelet therapy for Results A total of 110 cases were eligible (mean age: 56.7 years). The majority were female (81.8%) and received the Pipeline Embolization Device (83.6%). 7.3% of patients presented with ruptured aneurysms. More than 1 flow diverter was required in 7.3% of cases. The majority (90.9%) of the dual antiplatelet regimen involved aspirin 325 mg and clopidogrel 75 mg. Most patients were on dual antiplatelet therapy between 3–6 months in duration prior to transitioning to aspirin monotherapy (325 mg). In the shorter duration cohort, the thromboembolic complication rate was 9.3% compared to 12.5% in the longer duration cohort (p=0.76). Similarly, the hemorrhagic complication rate was 5.6% in the short duration cohort compared to 14.3% in the longer duration cohort (p=0.20). Conclusion A shorter duration of dual antiplatelet therapy after flow diversion was not associated with a higher thromboembolic complication rate. While the duration of antiplatelet therapy should be personalized for each patient, transitioning to monotherapy after 3 months is likely safe. Disclosures V. Ban: None. M. Pernik: None. T. Binyamin: None. J. Corona: None. Y. Kim: None. R. de Oliveira Sillero: None. R. Novakovic: None. G. Pride: None. J. Barr: None. J. White: None. H. Batjer: None. B. Welch: 2; C; Medtronic, Stryker, MicroVention. 6; C; Peter Lazic.

Introduction: Emergency Departments utilizing telestroke technology are less likely to meet American Heart Association/American Stroke Association’s recommended Door to Needle goal of less than 45 minutes. The Nursing Driven-Acute Stroke Care (NAS-Care) study tested effects of standardized stroke protocols on key workflow best practices. Methods: Seven non-academic stroke hospitals in the Lone Star Stroke Consortium’s network participated in this prospective, multi-site, baseline-controlled study from February 2015 - December 2018. After three months of blinded baseline data collection, the following interventions were implemented: NIHSS certification, nursing education including mock stroke codes, and a standardized flowsheet for code organization and documentation. The NAS-Care Run Sheet was also used to collect six months of post-intervention data. Results: Six hospitals completed the study. Study enrolment was halted after interim analysis of 447 patients, 180 in the pre-intervention control group and 267 in the post-intervention follow-up. The proportion of patients receiving alteplase was 18.9% (control) and 18.4% (intervention, NS). In the interim analysis, Door-to-ED Provider and Door-to-CT times were reduced after intervention while Door-to-Specialists and Door-to-Needle times were not significantly improved (table). Conclusion: Standardized nursing education and protocols improved staff-dependent initial stroke time metrics in Emergency Departments utilizing telestroke. Additional workflows for telestroke physicians may be required to optimize alteplase administration metrics. Final results of the NAS-Care study will be presented at the International Stroke Conference.

Type 2 diabetes mellitus (T2DM) increases cardiovascular complications. Diabetic vascular dysfunction is associated with the reduced activity of the different smooth muscle potassium (K

Background and objective The first pass effect (FPE) has become a novel measure for neurointerventionalists, achieving a complete recanalization with a single thrombectomy device pass, which has been shown to be associated with higher rates of good clinical outcomes. We describe and expand the FPE to one of a large US post-marketing registry (TRACK, Trevo Stent-Retriever Acute Stroke) to elucidate the effect of a single device pass and clinical outcome. Methods TRACK was a core-laboratory adjudicated multicenter registry of 634 patients from 23 centers aimed to evaluate the use of the Trevo device in everyday clinical practice. The TRACK registry was utilized to identify an FPE subgroup (n=140). Baseline features including demographics and clinical data were compared with the non-FPE patients (n=469). Clinical outcome measures included modified Rankin Scale score (mRS) at 30 and 90 days, National Institutes of Health Stroke Scale (NIHSS) score, symptomatic intracranial hemorrhage (sICH), and mortality. FPE was defined as a single pass/use of a device with TICI 2c/3 recanalization, and no use of rescue therapy. Results 609 patients were included in the FPE (140/609, 23%) vs non-FPE (469/609, 77%) subgroup analysis from the TRACK registry. There was no association between patient demographics and FPE group, including age (p=0.36), sex (p=0.50), race (p=0.49), location of occlusion (p=0.26), baseline NIHSS (p=0.61) past medical history including hypertension (p=0.57), atrial fibrillation (p=0.55), diabetes mellitus (p=0.74), hyperlipidemia (p=0.28), coronary artery disease (p=0.27), or history of smoking (p=0.12). The non-FPE group was associated with higher use of intraarterial tPA (FPE: 11% vs non-FPE: 23%). The onset to puncture time in minutes was not significantly different between groups (p=0.31); however, the total procedural time, total fluoroscopic time, and puncture to reperfusion time had significantly shorter mean time in FPE group (p Conclusion The achievement of complete revascularization from a single Trevo Stent-Retriever device pass is associated with higher rates of good clinical outcomes. Additionally, FPE in our subgroup registry analysis was associated with shorter procedural times, lower NIHSS at discharge, and significantly lower rates of EDT. Our analysis was not able to identify any patient demographics that would be associated to achieve first pass effect. Further research is warranted to confirm findings and identify additional factors achieving good clinical outcome after thrombectomy. Disclosures M. Mokin: 2; C; Claret Medical, Nogueira-Stryker Neurovascular (Trevo-2 Trial Principal Investigator; DAWN Trial Principal Investigator, TREVO Registry Steering Committee), Medtronic (SWIFT Trial Steering Committee; SWIFT-Prime Trial Steering Committee ; STAR Trial Angiographic Core Lab), Penumbra (3D Separator Trial Executive Committee), Neuravi (ARISE-2 Steering Committee), Genentech (Physician Advisory Board), Allm Inc (Physician Advisory Board). C. Primiani: None. A. Castonguay: None. R. Nogueira: None. D. Haussen: None. J. English: None. S. Satti: 2; C; Stryker Neurovascular. J. Chen: None. H. Farid: None. C. Borders: None. E. Veznedaroglu: None. M. Binning: None. A. Puri: None. N. Vora: None. R. Budzik: None. G. Dabus: None. I. Linfante: 2; C; Metronic, Stryker, Penumbra, and Cordis. V. Janardhan: None. A. Alshekhlee: None. M. Abraham: None. R. Edgell: None. M. Taqi: None. R. El Khoury: None. A. Majjhoo: None. M. Kabbani: None. M. Froehler: None. I. Finch: None. S. Ansari: None. R. Novakovic: None. T. Nguyen: None. O. Zaidat: 6; C; overall PI for TRACK, Arise II, Co-PI Therapy Trial, Steering committee STRATIS registry.

Objective: The overall risk of ischemic stroke from a chronically occluded internal carotid artery (COICA) is around 5%-7% per year despite receiving the best medical therapy. We propose a radiographic classification of COICA that can be used as a guide to determine the technical success and safety of endovascular recanalization for symptomatic COICA. Methods: The radiographic images of 100 consecutive subjects with COICA were analyzed. A new classification of COICA was proposed based on the morphology, location of occlusion, and presence or absence of reconstitution of the distal ICA. The classification was used to predict successful revascularization in 32 symptomatic COICAs in 31 patients. Patients were included in the study if they had a COICA with ischemic symptoms refractory to medical therapy. Results: Four types (A-D) of radiographic COICA were identified. Types A and B were more amenable to safe revascularization than types C and D. Recanalization was successful at a rate of 68.75% (22/32 COICAs; type A: 8/8; type B: 8/8; type C: 4/8; type D: 2/8). The perioperative complication rate was 18.75% (6/32; type A: 0/8 [0%]; type B: 1/8 [12.50%]; type C: 3/8 [37.50%], type D: 2/8 [25.00%]). None of these complications led to permanent morbidity or death. Twenty (64.52%) of 31 subjects had improvement in their symptoms at the 2-6 months' follow-up. A statistically significant decrease in systolic blood pressure (SBP) was noted in 17/21 (80.95%) patients who had successful revascularization, which persisted on follow-up (p = 0.0001). The remaining 10 subjects in whom revascularization failed had no significant changes in SBP (p = 0.73). Conclusions: The pilot study suggested that our proposed classification of COICA may be useful as an adjunctive guide to determine the technical feasibility and safety of revascularization for symptomatic COICA using endovascular techniques. Additionally, successful revascularization may lead to a significant decrease in SBP postprocedure. A Phase 2b trial in larger cohorts to assess the efficacy of endovascular revascularization using our COICA classification is warranted.

Background: Various techniques are used to enhance the results of mechanical thrombectomy with stent-retrievers, including proximal arrest with balloon guide catheter (BGC), conventional large bore proximal catheter (CGC), or in combination with local aspiration through a large-bore catheter positioned at the clot interface (Aspiration-Retriever Technique for Stroke [ARTS]). We evaluated the impact of ARTS in the North American Solitaire Acute Stroke (NASA) registry. Summary: Data on the use of the aspiration technique were available for 285 anterior circulation patients, of which 29 underwent ARTS technique, 131 CGC, and 125 BGC. Baseline demographics were comparable, except that ARTS patients are less likely to have hypertension or atrial fibrillation. The ARTS group had more ICA occlusions (41.4 vs. 22% in the BGC, p = 0.04 and 26% in CGC, p = 0.1) and less MCA/M1 occlusions (44.8 vs. 68% in BGC and 62% in CGC). Time from arterial puncture to reperfusion or end of procedure with ARTS was shorter than with CGC (54 vs. 91 min, p = 0.001) and was comparable to the BGC time (54 vs. 67, p = 0.11). Final degree of reperfusion was comparable among the groups (TICI [modified Thrombolysis in Cerebral Infarction] score 2b or higher was 72 vs. 70% for CGC vs. 78% for BGC). Procedural complications, mortality, and good clinical outcome at 90 days were similar between the groups. Key Messages: The ARTS mechanical thrombectomy in acute ischemic stroke patients appears to yield better results as compared to the use of CGCs with no significant difference when compared to BGC. This early ARTS technique NASA registry data are limited by the earlier generation distal large bore catheters and small sample size. Future studies should focus on the comparison of ARTS and BGC techniques.

Mechanical thrombectomy using retrievable stents or stent retriever devices has become the mainstay of intra-arterial therapy for acute ischemic stroke. The recent publication of a series of positive trials supporting intra-arterial therapy as standard of care for the treatment of large vessel occlusion will likely further increase stent retriever use. Rarely, premature stent detachment during thrombectomy may be encountered. In our multicenter case series, we found a rate of detachment of less than 1% (n = 7/1,067), and all were first-generation Solitaire FR devices. A review of the US Food and Drug Administration database of device experience yielded 90 individual adverse reports of detachment. There were 82, 1 and 7 detachments of Solitaire FR (first generation), Solitaire FR2 (second generation) and Trevo devices, respectively. We conclude with a brief overview of the technical and procedural considerations which may be helpful in avoiding this rare complication.

In this study, we researched the effects of maternal subclinical hypothyroidism on the amniotic fluid cells oxidative metabolism during the first trimester of pregnancy. Oxidative stress and damage biomarkers were assayed in the amniotic fluid cells of healthy and pregnant women with subclinical hypothyroidism. Obtained results show that amniotic fluid cells of pregnant women with subclinical hypothyroidism have significantly higher concentrations of oxidative stress biomarkers (superoxide anion, nitric oxide, peroxynitrite) and oxidative damage (lipid peroxide and micronuclei frequency), but lower concentrations of hydrogen peroxide and oxidized glutathione in comparison to healthy pregnant women. We also showed that oxidative stress biomarkers were positively correlated with micronuclei frequency and lipid peroxide concentration in amniotic fluid cells of pregnant women with subclinical hypothyroidism. The present study provides the first evidence for prooxidative effects of maternal subclinical hypothyroidism on the fetus obtained by the estimating oxidative metabolism in the amniotic fluid cells.

Purpose: Hypothyroidism in pregnancy is the serious state that may lead to fetal morbidity and mortality. Oxidative stress biomarkers in the amniotic fluid can provide important information on the health, development and maturation of the fetus during pregnancy. In this study, we examined whether maternal hypothyroidism contributes to increased oxidative stress biomarkers in the amniotic fluid during the first trimester of pregnancy. Materials and methods: The study was conducted on healthy pregnant women and pregnant women with hypothyroidism (gestational age: 16-18 weeks). Oxidative stress biomarkers, such as superoxide anion (O2•-), hydrogen peroxide (H2O2), nitric oxide (NO), peroxynitrite (ONOO-), lipid peroxide (LPO), reduced glutathione (GSH) and oxidized glutathione (GSSG) were assayed in the amniotic fluid. Results: The results of this study indicated that concentrations of O2•- and NO are significantly higher, while the concentration of H2O2 is significantly lower in the amniotic fluid of pregnant women with hypothyroidism in comparison to healthy pregnant women. There were no differences in concentrations of LPO, GSH and GSSG among tested groups. Also, we found that amniotic fluid concentration of O2•- is negatively correlated with the body weight and Apgar score values of the newborns. Conclusion: These results suggest that pregnancy hypothyroidism is characterized by the amniotic fluid oxidative stress. Incorporation of the oxidative stress biomarkers measurement in the amniotic fluid may be of clinical importance in the management of pregnancy hypothyroidism.

PurposeMonitoring of blood pressure (BP) during procedures is variable, depending on multiple factors. Common methods include sphygmomanometer (BP cuff), separate radial artery catheterization, and side port monitoring of an indwelling sheath. Each means of monitoring has disadvantages, including time consumption, added risk, and signal dampening due to multiple factors. We sought an alternative approach to monitoring during procedures in the catheterization laboratory.MethodsA new technology involving a 330 µm fiberoptic sensor embedded in the wall of a sheath structure was tested against both radial artery catheter and sphygmomanometer readings obtained simultaneous with readings recorded from the pressure sensing system (PSS). Correlations and Bland–Altman analysis were used to determine whether use of the PSS could substitute for these standard techniques.ResultsThe results indicated highly significant correlations in systolic, diastolic, and mean arterial pressures (MAP) when compared against radial artery catheterization (pConclusionsThe PSS has competitive functionality to that seen with a dedicated radial artery catheter for BP monitoring and is available immediately on sheath insertion without the added risk of radial catheterization. The sensor is structurally separated from the primary sheath lumen and readings are unaffected by device introduction through the primary lumen. Time delays and potential complications from radial artery catheterization are avoided.

Background and Purpose: Endovascular therapy (EVT) with stent-retrievers is safe and effective within 6-8hours of acute ischemic stroke onset; however a large proportion of patients present beyond 8hrs. There is a paucity of data on the safety and effectiveness of EVT in this latter population. Methods: We reviewed demographic, clinical, procedural and clinical outcomes data from consecutive patients treated with the Solitaire™ FR device in the investigator-initiated NASA Registry. Patients were divided into early (≤8hrs) and late (>8hrs) presenting groups. Primary outcomes (90-day mRS 0-2, mortality, and symptomatic ICH) were compared. Results: Three hundred and fifty-four patients from 24 centers were enrolled in NASA. Sixty-three (18%) patients presented >8hrs from onset and were treated. Baseline demographic and procedural factors were comparable between the early and late groups, except for time-to-treatment (271.9±97.3min vs. 754±269.3min, p Conclusions: The NASA Registry has demonstrated that clinical outcomes of patients treated >8hrs from stroke onset are favorable and comparable to the outcomes of patients treated earlier. Later treatment in these selected patients was not associated with an increased risk of symptomatic ICH. Future trials should prospectively evaluate the benefit of EVT beyond 8hrs.

Background and Purpose: Recent randomized clinical trial (RCTs) demonstrated efficacy of mechanical thrombectomy using stent-retrievers in acute ischemic stroke (AIS) patients. The main purpose of TRevo ACute Ischemic StroKe (TRACK) stent-retriever thrombectomy multicenter registry is to demonstrate safety and efficacy in real life clinical practice. Methods: The investigator-initiated TRACK multicenter registry recruited 24 sites in north America to submit demographic, clinical, site-adjudicated angiographic, and outcome data on consecutive AIS patients treated with Trevo stent-retriever device as the first treatment option. Standard clinical safety (symptomatic intracranial hemorrhage (sICH), and mortality) and efficacy (revascularization and disability) outcomes and predictors of clinical outcome were analyzed. Results: 624 patients were enrolled in the TRACK registry. Median age was 68 years (range 16-94, 118 (18.1%) >80), male gender was 51.4%, and 67.7% were white. The median National Institutes of Health Stroke Severity Scale (NIHSS) was 17 (IQR 13-22). Transfer cases were 50.6% with IV-rtPA use in 318 cases (51.3%). Median onset to groin puncture (OTG) time was 283 min (IQR 198.5-443), and groin puncture to revascularization was 66 min (IQR 37.5-103). Anterior circulation occlusion was 86.2% (MCA/M2 in 55.2% followed by ICA in 15.9% and M2 in 12.7%). Use of GA was in 389 cases (62.3%), number of passes were ≤ 3 in 92% of the cases (1: 45.2%, 2:28%, and 3:18.7%), 291 (46.7%) had BGC use. Rescue use was seen in 21.7%. Revascularization of ≥ TIMI 2 was 81.8% and ≥ TICI 2b was 70%. The primary outcome of mRS of ≥ 2 was 48.3% in the full cohort, and 50.6% in TREVO-2 like group. sICH and mortality were 7.2%, and 20.1% in the full cohort vs 6.9% and 17.5% in the TREVO-2 like group, respectively. The independent predictors of clinical outcome were lower baseline NIHSS, younger age, use of BGC, successful recanalization, and no general anesthesia (GA). Conclusions: The real life clinical practice Trevo registry demonstrated good clinical outcome and high rate of recanalization. Younger age, lower baseline NIHSS, use of balloon guide catheter, successful recanalization, and avoiding endotrachaeal GA independent predictors of good clinical outcome.

La presente attività di ricerca si inserisce nell'ambito del progetto ESA "OXYTHERM" (AO-2009-1136) con l'obiettivo di preparare e supportare gli esperimenti che saranno condotti sulla facility sperimentale MSL-EML nella stazione spaziale internazionale. Tali esperimenti hanno lo scopo condotti allo scopo di valutare, anche in condizioni di microgravità, l'influenza della pressione parziale di ossigeno e delle condizioni fluidodinamiche dei processi di trasporto tra fase gas e fase liquida, sulla tensione superficiale e altre proprietà termo fisiche di leghe binarie e sistemi più complessi di interesse industriale. I risultati ottenuti saranno di utilità per l'ottimizzazione dei processi tecnologici quali saldatura, processi di giunzione, casting, crescita di monocristalli, produzione di materiali compositi e schiume metalliche. Nonostante la fenomenologia dei processi di interazione con ossigeno siano a livello industriale così determinanti nell'ottenere un prodotto finale di elevata qualità ed esente da difetti, la letteratura a disposizione e' carente e poco contribuisce a chiarire sopratutto i meccanismi di interazione (adsorbimento e formazione di fasi di ossido stabile) e trasporto all'interfaccia metallo liquido-atmosfera. Per questo motivo, la ricerca qui presentata focalizza il suo programma e la sua attività nello studiare, tramite un approccio combinato teorico-sperimentale, il comportamento di alcuni sistemi binari scelti come sistemi modello (Ag-Cu e Cu-Sn) nei confronti di atmosfere più o meno ossidanti. La campagna sperimentale di supporto a terra, è stata organizzata seguendo uno studio sistematico dei parametri operativi in un ampio intervallo di composizione e temperatura. Le misure di tensione superficiale sono state eseguite su metalli puri e leghe binarie sia in condizioni riducenti, sia in condizioni di ossidazione controllata.

Ischemic stroke is a leading cause of death and disability worldwide. Much of the long-term disability occurs in patients with Emergent Large Vessel Occlusion (ELVO). In fact, in these patients, occlusion of a major intracerebral artery results in a large area of brain injury often resulting in

Ag-based alloys have industrial importance also in relation to their use as high temperature solders in jewellery [1]. Silver solders usually are based on the Ag-Cu binary system, nevertheless Zn can be considered a candidate for replacing copper; it reduces the melting point of solder increases the fluidity of the alloys and deoxidizes the melt. Furthermore, the very good tarnish-resistance of Ag-Ge and Ag-Ge-Zn alloys [2] make them good candidates for bonding sterling silver (Ag92.5Cu7.5, wt %) which are commonly used in jewellery due to their very special lustre and very good mechanical properties. Moreover, the addition of Ge to sterling silver alloys can greatly reduce the oxidation during melting and casting. Concerning Ag-Ge-Zn alloys, neither literature data on their phase diagram nor on thermodynamic properties are available. The experimental investigation of the Ag-Ge-Zn phase diagram was performed by using combined microstructural, XRD and Differential Scanning Calorimeter (DSC) analyses. The samples were subjected to thermal analysis by a heat-flux DSC apparatus with heating and cooling rate of 0.5 or 0.3 °C/min. The microstructure of the samples, both after annealing and after DSC analysis, was studied by optical and scanning electron microscopy. Considering the slow heating and cooling rate, the isothermal section at room temperature was established. No ternary compounds were observed. On the basis of the experimental investigations the invariant reactions were identified. [1] Welding, Brazing and Soldering, ASM Handbook, Vol.6, eds. J.R. Davis, K. Ferjutz, N.D. Wheaton, M.S. Woods, ASM International, 1993. [2] M.R. Pinasco, G. Pellati, A. Saccone, G. Borzone, E. Ricci, R. Novakovic, A. Passerone, "Leghe a base di argento e procedimenti per la loro realizzazione, particolarmente per la fabbricazione di gioielli". Patent (2006). N. GE2006A000118

During heating, nanoparticles undergo to specific phenomena such as coalescence, which affect their phase stability. This aspect is of great importance for the potential application of nanosized metallic system. The driving force for the coalescence of two nanoparticles is the surface energy reduction due to lower surface area of the new nanoparticle. In fact, the process begins with the contact of nanoparticles and is followed by the alignment of the coalescing planes at the interface and by the subsequent growth of the neck. The studies of the coalescence processes involve nanoparticles diffusion, nanoparticles properties relevant to the diffusion, such as melting points, volumes and diffusion coefficients as well as overall coalescence mechanisms. The nanoparticles growth at high temperature by coalescence have been analyzed by means of the theoretical predictions; an important parameter for predicting the final particle size is the rate of coalescence. The results obtained are compared to the experimental data available in literature.

Thermophysical properties of liquid Si-Te alloys are interesting for electronic industry. However, despite the importance of these properties, the determination of their thermophysical properties is often lacking due to the experimental difficulties related to high melting temperatures. Therefore, it is possible to estimate the missing values by using theoretical models. The energetics of mixing in liquid Si-Te system has been analyzed through the study of the concentration dependence of various thermodynamic, surface (surface tension and surface composition) and structural properties (concentration fluctuations in the long-wavelength limit and chemical short-range order parameter) in the framework of the Compound Formation Model (CFM) and Quasi Chemical Approximation for regular solutions (QCA), and subsequently were compared with the data available in literature.

Corrosion behaviour of ferritic and ferritic-martensitic oxide dispersed strengthened (ODS) steels woth different chromium content (9, 12 and 14 % Cr) have been tested in stagnant liquid lead with an oxygen concentration cO2 = 10-6 wt%. The study has been carried out with the aim to identify the most appropriate structural materials for advanced nuclear energy system and waste transmutation system. [...]

Chemokines and corresponding receptor interactions have been shown to be involved in prostate cancer (PCa) progression and organ-specific metastasis. We have recently shown that PCa cell lines and primary prostate tumors express CXCR5, which correlates with PCa grade. In this study, we present the first evidence that CXCL13, the only ligand for CXCR5, and IL-6 were significantly elevated in PCa patient serum compared to serum from subjects with benign prostatic hyperplasia (BPH), or high-grade prostatic intraepithelial neoplasia (HGPIN) as well as normal healthy donors (NHD). Serum CXCL13 levels significantly (p < 0.0001) correlated with serum prostate-specific antigen (PSA), whereas serum IL-6 levels significantly (p < 0.0003) correlated with CXCL13 serum levels. CXCL13 was found to be a better predictor of PCa than PSA. In addition, CXCL13 was highly expressed by human bone marrow endothelial (HBME) cells and osteoblasts (OBs), but not osteoclasts (OCs), following treatment with physiologically relevant levels of interleukin-6 (IL-6). We further demonstrate that CXCL13, produced by IL-6-treated HBME cells, was able to induce PCa cell invasion in a CXCR5-dependent manner. CXCL13-mediated PCa cell αvβ3-integrin clustering and adhesion to HBME cells was abrogated by CXCR5 blockade. These results demonstrate that the CXCL13-CXCR5 axis is significantly associated with PCa progression.

The surface tension of the Cu-Sn system has been measured over the whole composition range by using the large drop method over the temperature range T ) (430 to 1300) K. The measurements were carried out at equilibrium and under "oxygen-free" conditions. The results obtained were compared with the available literature data as well as with theoretical values calculated by the compound formation model (CFM) and quasi chemical approximation for regular solution (QCA). In addition, dynamic surface tension measurements have been performed to study the evolution of the molten alloy surface in the presence of trace amounts of oxygen in the surrounding atmosphere. The general physico-mathematical formalism developed by our group to study liquid binary alloys and their oxides has been applied to describe the interactions in Cu-Sn melts under an oxidizing atmosphere. The experimental findings validate the model predicting the oxidation phenomena which contribute to maintain the interface cleanness and to determine the boundary separating oxidation and deoxidation regimes.

The thermodynamic properties of liquid In-Sn alloys indicate a weak interactions between unlike atoms. The new In, Sn and In-Sn surface tension experimental data set obtained by the large-drop method over the temperature range 523-923 K together with the literature data on different thermophysical properties substantiate a nearly ideal mixing behaviour of these alloys. A low interaction energies do not effect the composition dependence of thermophysical properties, in particular the surface tension and the surface segregation. In order to estimate the effects of the short-range order phenomenon on the surface properties of In-Sn liquids, the QCA (quasi chemical approximation) for the regular solution model and the CFM (compound formation model) have been applied. In the same framework the transport properties and the structural characteristics of liquid In-Sn alloys have also been analysed.

The surface tension, density, and viscosity of the Ni-based superalloy CMSX-4® have been determined in the temperature ranges of 1,650–1,850 K, 1,650–1,950 K, and 1,623–1,800 K, respectively. Each property has been measured in parallel by different techniques at different participating laboratories, and the results are compared with the aim to improve the reliability of data and to identify recommended values. The following relationships have been proposed: density-ρ (T) [kg· m−3] = 7,876 − 1.23(T − 1,654 K); surface tension-γ (T) [mN·m−1] = 1,773 − 0.56 (T − 1, 654 K); viscosity-η (T) [mPa·s] = 8.36 − 1.82 × 10−2(T − 1,654 K). For a comparison, surface-tension measurements on the Al-88.6 at% Ni liquid alloy with the same Al-content as the CMSX-4® alloy were also performed. In addition, the surface tension and density have been theoretically evaluated by different models, and subsequently compared with new experimental data as well as with those reported in the literature. The surface-tension experimental data for the liquid CMSX-4® alloy were found to be close to that of the Al-88.6 at% Ni alloy which is consistent with results from the compound formation model (CFM).

A peculiar feature of the Mg-Pd phase diagram is the presence of several "Complex Metal Alloys (CMAs)" which are phases with giant unit cells and inherent structural disorder; their structure can be described with Mackay clusters as fundamental structural unit [1]. These polyhedra consist in an arrangement of 52 atoms disposed in three shells with local icosahedral order: the first is an icosahedron, the second an icosidodecaedron and the third another icosahedron. The assessment of the Mg-Pd phase diagram was published in 1988 [2] with many uncertainties and subsequently, considering the existence of the CMAs, was revised by [1]. At present a definitely assessed version of the Mg-Pd phase diagram is not available, and great differences can be found for instance in the formation of the Mg6Pd phase which is indicated to be a peritectic one by [2] and having a congruent melting by [1]. As for the standard enthalpies of formation (?fH°) there is a great lack in literature for the Mg-Pd phases; nowadays predictive methods are very developed, but it is not trivial to apply common models to giant cells like those of the CMAs. Based on the phase diagram evidence of a several intermetallic compounds, the mixing behaviour of liquid Mg-Pd alloys has been analysed through the study of thermodynamic, surface and structural properties in the framework of compound formation model (CFM) and quasi chemical approximation (QCA) for regular solution.

In the framework of OXYTHERM ESA-MAP Project, a systematic study of oxygen influence on molten Ag-Cu alloys, taken as binary model system, was performed. The project is aimed to the development of improved physico-chemical models providing a deeper understanding of the basic interaction mechanisms of oxygen on liquid alloys and on the influence on their thermophysical properties such as surface tension, viscosity, and density. It exploits measurements performed on board of the ISS by using MSL-EML facility equipped with the Oxygen Sensing and Control device (OSC), in order to obtain information will serve as a benchmark for the quality of ground based experiments. In this work, the interactions between Ag-Cu molten alloys and an oxidising atmosphere are theoretically approached by applying different models: a thermodynamic Belton's like model [1], which allows the adsorption isotherms to be evaluated and a fluid dynamic model [2], which allows to determine the boundary separating oxidation and de-oxidation regimes, for the liquid alloys surface. The models have been validated by surface tension data measured as a function of oxygen partial pressure in two different apparatuses by using a containerless- and a container- based technique, respectively. The former is very similar to the device, named TEMPUS, designed by DLR, that is used on the ISS for the microgravity measurements. In this apparatus the surface tension was measured by oscillating drop method using electromagnetic levitation (EML) over a wide range of temperatures above the melting point and under oxygen control (OSC)[3]. In the other one, dynamic surface tension measurements [4] have been performed by the large drop method in order to study the evolution of the molten alloy surface in the presence of traces amount of oxygen. Such measurements are out of equilibrium and they can provide information about the kinetics and the mechanisms of mass transfer to and through the surface. [1] R. Novakovic R., D. Giuranno, E. Ricci, Molten 2009 Proceeding article n. cap. 02 ( 2009) 70. [2] E. Arato, M. Bernardi, D. Giuranno, E. Ricci, Applied Surface Sci. 258 (2012) 2686. [3]M. Schulz, J. Brillo, C.Stenzel, H. Fritze , Solid State Ionics 225 (2012) 332. [4] E. Ricci, E. Arato, A. Passerone, P. Costa, Advance of Colloid and Interface Science 117 (2005) Acknowledgements: This work was performed in the framework of the European Space Agency (ESA) Microgravity Applications Support Programme (MAP) and supported by the Italian Space Agency (ASI) under contract DC-MIC-2011-036 "OXYTHERM".

Thermophysical properties of liquid Co-Si alloys are interesting for composite materials production. However, despite the importance of these properties, the determination of their thermophysical properties is lacking due to the experimental difficulties related to high melting temperatures as well as due to the high reactivity of these alloys with crucible materials. The energetics of mixing in liquid Co-Si system has been analyzed through the study of the concentration dependence of various thermodynamic, surface (surface tension and surface composition) and structural properties (concentration fluctuations in the long-wavelength limit and chemical short-range order parameter) in the framework of the Compound Formation Model (CFM) and Quasi Chemical Approximation for regular solutions (QCA). The surface tension of a few Co-Si liquid alloys has been measured as a function of temperature above the corresponding liquidus temperatures. The results obtained were discussed with respect to both, temperature and concentration, and subsequently were compared with the aforementioned thermodynamic models.

A classical molecular dynamics code developed in Baletto's group will be applied to the study the growth of PtCu nanoalloys at different temperatures and conditions. A Common Neighbour Analysis will be used to investigate the structures and their chemical order on-the-fly during the growth process in order to identifying any phase changes and structural and chemical tendencies. The outcome will be compared with the corresponding results obtained by the models of growth, aiming to study the dominant mechanisms of the coalescence process (the surface diffusion and/or Ostwald ripening). The structural properties of the Pt-Cu system in the relevant bulk material will be also studied.

In recent years, bimetallic nanoparticles (NPs) have gained much attention due to their applications as catalysts, in electronics, electro-optics and for changes in surface plasma band energy [1, 2]. Various synthesis techniques have been reported in literature, both physical and chemical methods and also a combination of them. The shape, size, composition, crystalline nature of the produced Nps depends on the processing route and the experimental conditions. Our joint research aims to investigate the melting temperature depression of metallic synthesized by one-pot method. Metallic nanoparticles of Ag, Cu, and Ag-Cu and Ag-Sn eutectic alloys have been prepared by a low temperature chemical reduction method in different media (aqueous solution or anhydrous methanol) adopting potassium or sodium borohydride as a reducing agent. X-ray powder diffraction (XRD) and Transmission Electron Microscopy (TEM) was used to determine the crystalline nature of the samples, the size and the composition of the particles. The thermal behaviour of the samples has been investigated by Differential Scanning Calorimetry (DSC). The results obtained will be used to validate available theoretical models concerning the dependence of the melting temperature depression on the nanoparticle size [3]. References [1] M. Ganjali, M. Ganjali, S. Khoby, M. A. Meshkot, Nano-Micro Lett., 3 (2011) 256-263. [2] H.S. Nalwa, Handbook of Nanostructured Materials and Nanotechnology, Vol 1, Synthesis and Processing, Academic Press, 2000. [3] A. Barybin, V. Shapovalov, J. of Appl. Phys., 109 (2011) 034303.

The research on new energy sources, in particular renewable and environmentally clean ones, started recently because of the limited availability and the pollution produced by fossil fuels. The sun is one of the cleanest and most abundant energy sources. The photovoltaic industry is mostly based on silicon technologies. Silicon is an indirect band gap material and is needed to produce perfect mono-crystals in order to obtain high efficiency solar modules, resulting in an increase in the costs [1]. As a consequence, the research on thin film technology is being developed and is based on direct bad gap materials such as CIS (CuInSe2), CIGS (CuInxGa1-xSe2 with 0

A theoretical model of grain growth in sintering of clustered powder compacts is outlined, showing that the microstructure evolution is stepwise continuous in time and its general trends can be predicted independently of the particular system and process being considered. The dependence of coarsening on densification can be accounted for by introducing a densification-scaled time variable (intrinsic time). The theory is successively applied to systems where particular local mechanisms of matter transport are supposed to operate, respectively in the initial/intermediate and the intermediate/final stage of sintering. The obtained mathematical models are solved numerically to follow the evolution of three regularly packed clusters. The model predictions are in good agreement with experimental data obtained by other researchers.

To determine the importance of perineural invasion (PNI) on diagnostic biopsy in men enrolled in active surveillance (AS).Eligibility criteria for AS included clinical stage ≤ T2a and Gleason score ≤6, ≤3 cores positive, maximum single core involvement50%, and total tumour volume ≤5% on diagnostic biopsy. All men received 12-core confirmation biopsy at ≤6 months. AS 'failure' on confirmatory biopsy was defined as failure to meet one or more eligibility criteria. Risk of AS failure was compared in men with and without PNI.For the 165 men comprising the study population, the mean (sd) age was 66.9 (6.5) years and the median (interquartile, IQR) PSA level of men at study entry was 4.4 (3.2-6.0) ng/mL. The median (IQR) follow-up was 5.5 (1.1-9.9) months. In all, 8.5% (14/165 men) had PNI on diagnostic biopsy. Compared with those without PNI, men with PNI tended to have more cores involved with cancer, at a mean (sd) of 2.0 (0.7) vs 1.6 (0.8) cores (P = 0.08) but did not have significantly a greater mean (sd) total tumour length on diagnostic biopsy, at 3.0 (2.1) vs 2.3 (3.6) mm (P = 0.27). Men with PNI on diagnostic biopsy were significantly more likely to meet criteria for disease progression on confirmatory biopsy (57% [8/14] vs 21% [32/151]; P = 0.006). PNI remained a significant predictor for AS failure after adjustment for number of positive cores, maximum percentage core involvement, and total tumour length (odds ratio 4.4, 95% confidence interval 1.4-14.2).PNI on diagnostic biopsy is associated with disease progression on confirmatory biopsy. The presence of PNI should factor into appropriate patient selection and counselling in AS.

This study was aimed to evaluate resveratrol (1-100 μM) effect on the spontaneous rhythmic contractions (SRC), oxytocin-induced (0.2 nM, POxC) phasic and tonic (20 nM, TOxC) contractions of isolated rat uterus. The SRC and POxC were more sensitive to resveratrol than TOxC (pD2 values: 4.53 and 4.66 versus 4.06). Different blockers of K(+) channels (glibenclamide, tetraethylamonium, iberiotoxin, 4-aminopyridine) antagonized the response to resveratrol on the SRC and phasic contractions, but did not antagonize the effect of resveratrol on the TOxC. In order to compare the relaxant activities of resveratrol on the TOxC with that of potassium channel openers, a separate experiments with NS 1619, a highly specific big Ca(2+)-sensitive K(+) (BKCa) channels opener and pinacidil, a predominant opener of ATP-sensitive K(+) (KATP) channels were done. NS 1619 (10-100 μM) and pinacidil (10-100 μM) produced more potent inhibition of TOxC than resveratrol (pD2 values were 6.00 and 5.29). Iberiotoxin, a highly selective BKCa channels blocker, antagonized the response to NS 1619 and glibenclamide, a highly selective KATP channels blocker, antagonized the response to pinacidil on the TOxC. To test K(+)- and extracellular Ca(2+)- independent mechanism(s) of resveratrol on TOxC, a K(+)-rich, Ca(2+)-free solution was used. Under this condition, only high concentrations (≥30 μM) of resveratrol inhibited TOxC. Western blots analysis confirmed expression of Kir6.1, Kir6.2, KCa1.1, Kv2.1 and Kv4.2. channel proteins in myometrium. Thus, the effect of resveratrol is dependent on the types of contractions. The inhibitory response of resveratrol on the SRC and phasic contractions involves different myometrial K(+)- channels. When applied in high concentrations, resveratrol has an additional K(+)- channels independent mechanism(s) of action. As the effects of NS 1619, pinacidil and resveratrol on the TOxC are different, we can conclud that resveratrol does not behave as a classical potassium channel opener.