Value of Automatically Derived Full Thrombus Characteristics: An Explorative Study of Their Associations with Outcomes in Ischemic Stroke Patients

(1) Background: For acute ischemic strokes caused by large vessel occlusion, manually assessed thrombus volume and perviousness have been associated with treatment outcomes. However, the manual assessment of these characteristics is time-consuming and subject to inter-observer bias. Alternatively, a recently introduced fully automated deep learning-based algorithm can be used to consistently estimate full thrombus characteristics. Here, we exploratively assess the value of these novel biomarkers in terms of their association with stroke outcomes. (2) Methods: We studied two applications of automated full thrombus characterization as follows: one in a randomized trial, MR CLEAN-NO IV (n = 314), and another in a Dutch nationwide registry, MR CLEAN Registry (n = 1839). We used an automatic pipeline to determine the thrombus volume, perviousness, density, and heterogeneity. We assessed their relationship with the functional outcome defined as the modified Rankin Scale (mRS) at 90 days and two technical success measures as follows: successful final reperfusion, which is defined as an eTICI score of 2b-3, and successful first-pass reperfusion (FPS). (3) Results: Higher perviousness was significantly related to a better mRS in both MR CLEAN-NO IV and the MR CLEAN Registry. A lower thrombus volume and lower heterogeneity were only significantly related to better mRS scores in the MR CLEAN Registry. Only lower thrombus heterogeneity was significantly related to technical success; it was significantly related to a higher chance of FPS in the MR CLEAN-NO IV trial (OR = 0.55, 95% CI: 0.31-0.98) and successful reperfusion in the MR CLEAN Registry (OR = 0.88, 95% CI: 0.78-0.99). (4) Conclusions: Thrombus characteristics derived from automatic entire thrombus segmentations are significantly related to stroke outcomes.

Role of intravenous alteplase on late lesion growth and clinical outcome after stroke treatment

Several acute ischemic stroke mechanisms that cause lesion growth continue after treatment which is detrimental to long-term clinical outcome. The potential role of intravenous alteplase treatment (IVT), a standard in stroke care, in cessing the physiological processes causing post-treatment lesion development is understudied. We analyzed patients from the MR CLEAN-NO IV trial with good quality 24-hour and 1-week follow-up Non-Contrast CT scans. We delineated hypo- and hyper-dense regions on the scans as lesion. We performed univariable logistic and linear regression to estimate the influence of IVT on the presence (growth > 0 ml) and extent of late lesion growth. The association between late lesion growth and mRS was assessed using ordinal logistic regression. Interaction analysis was performed to evaluate the influence of IVT on this association. Of the 63/116 were randomized to included patients, IVT. Median growth was 8.4(-0.88-26) ml. IVT was not significantly associated with the presence (OR: 1.24 (0.57-2.74, p = 0.59) or extent (β = 5.1(-8.8-19), p = 0.47) of growth. Late lesion growth was associated with worse clinical outcome (aOR: 0.85(0.76-0.95), p < 0.01; per 10 ml). IVT did not influence this association (p = 0.18). We did not find evidence that IVT influences late lesion growth or the relationship between growth and worse clinical outcome. Therapies to reduce lesion development are necessary.

Abstract 113: Detection Of Patent Foramen Ovale In Patients With Ischemic Stroke On Prospective ECG-gated Cardiac CT Compared To Transthoracic Echocardiography

Background: Cardiac CT acquired during the acute stroke imaging protocol is an emerging alternative to transthoracic echocardiography (TTE) to screen for sources of cardioembolism, but its diagnostic accuracy to detect patent foramen ovale (PFO) is unclear.

Methods: This was a substudy of Mind the Heart, a prospective single-center cohort study in which consecutive adult patients with acute ischemic stroke underwent prospective ECG-gated cardiac CT during the initial stroke imaging protocol. Patients also underwent routine work-up, including TTE. We included patients <60 years who underwent TTE with agitated saline contrast (cTTE). Presence of a PFO on CT and cTTE was scored according to predefined criteria by a cardioradiologist and cardiologist, respectively, who were blinded to each other’s scoring. On CT, PFO was defined as a crypt shaped contrast jet from the left atrium to the right atrium towards the vena cava or an atrium septum discontinuity. On cTTE, a PFO was defined as the appearance of microbubbles in the left atrium within 3-6 cardiac beats after opacification of the right atrium. We assessed the sensitivity and specificity of cardiac CT for the detection of PFO using cTTE as the reference standard.

Results: Of 452 patients in Mind the Heart, 92 were younger than 60 years. Of these, 56 (61%) patients underwent both cardiac CT and cTTE and were included. Median age was 55 (interquartile range [IQR] 49-57) years and 38 (68%) were male. In total, 32/56 (57%) patients had cryptogenic stroke and their median Risk of Paradoxical Embolism score was 6 (IQR 6-7). Cardiac CT detected a PFO in 5/56 (9%) patients, 3 of which were confirmed on cTTE. cTTE detected a PFO in 12/56 (21%) patients. The sensitivity and specificity of cardiac CT were 25% (95%CI: 5-57%) and 95% (95%CI: 85-99%), respectively. Positive and negative predictive value were 59% (95%CI: 22-87) and 83% (95%CI: 77-87), respectively

Conclusion: Due to its low sensitivity, prospective ECG-gated cardiac CT does not appear to be a suitable screening method for PFO. If cardiac CT is used to screen for cardioembolism, additional echocardiography remains indicated in patients with cryptogenic stroke in whom PFO detection would have therapeutic consequences.

Factor XIa inhibition with asundexian after acute non-cardioembolic ischaemic stroke (PACIFIC-Stroke): an international, randomised, double-blind, placebo-controlled, phase 2b trial

BACKGROUND

Asundexian (Bayer AG, Leverkusen, Germany), an oral small molecule factor XIa (FXIa) inhibitor, might prevent thrombosis without increasing bleeding. Asundexian's effect for secondary prevention of recurrent stroke is unknown.

METHODS

In this randomised, double-blind, placebo-controlled, phase 2b dose-finding trial (PACIFIC-Stroke), patients with acute (within 48 h) non-cardioembolic ischaemic stroke were recruited from 196 hospitals in 23 countries. Patients were eligible if they were aged 45 years or older, to be treated with antiplatelet therapy, and able to have a baseline MRI (either before or within 72 h of randomisation). Eligible participants were randomly assigned (1:1:1:1), using an interactive web-based response system and stratified according to anticipated antiplatelet therapy (single vs dual), to once daily oral asundexian (BAY 2433334) 10 mg, 20 mg, or 50 mg, or placebo in addition to usual antiplatelet therapy, and were followed up during treatment for 26-52 weeks. Brain MRIs were obtained at study entry and at 26 weeks or as soon as possible after treatment discontinuation. The primary efficacy outcome was the dose-response effect on the composite of incident MRI-detected covert brain infarcts and recurrent symptomatic ischaemic stroke at or before 26 weeks after randomisation. The primary safety outcome was major or clinically relevant non-major bleeding as defined by International Society on Thrombosis and Haemostasis criteria. The efficacy outcome was assessed in all participants assigned to treatment, and the safety outcome was assessed in all participants who received at least one dose of study treatment. This study is registered with ClinicalTrials.gov, NCT04304508, and is now complete.

FINDINGS

Between June 15, 2020, and July 22, 2021, 1880 patients were screened and 1808 participants were randomly assigned to asundexian 10 mg (n=455), 20 mg (n=450), or 50 mg (n=447), or placebo (n=456). Mean age was 67 years (SD 10) and 615 (34%) participants were women, 1193 (66%) were men, 1505 (83%) were White, and 268 (15%) were Asian. The mean time from index stroke to randomisation was 36 h (SD 10) and median baseline National Institutes of Health Stroke Scale score was 2·0 (IQR 1·0-4·0). 783 (43%) participants received dual antiplatelet treatment for a mean duration of 70·1 days (SD 113·4) after randomisation. At 26 weeks, the primary efficacy outcome was observed in 87 (19%) of 456 participants in the placebo group versus 86 (19%) of 455 in the asundexian 10 mg group (crude incidence ratio 0·99 [90% CI 0·79-1·24]), 99 (22%) of 450 in the asundexian 20 mg group (1·15 [0·93-1·43]), and 90 (20%) of 447 in the asundexian 50 mg group (1·06 [0·85-1·32]; t statistic -0·68; p=0·80). The primary safety outcome was observed in 11 (2%) of 452 participants in the placebo group versus 19 (4%) of 445 in the asundexian 10 mg group, 14 (3%) of 446 in the asundexian 20 mg group, and 19 (4%) of 443 in the asundexian 50 mg group (all asundexian doses pooled vs placebo hazard ratio 1·57 [90% CI 0·91-2·71]).

INTERPRETATION

In this phase 2b trial, FXIa inhibition with asundexian did not reduce the composite of covert brain infarction or ischaemic stroke and did not increase the composite of major or clinically relevant non-major bleeding compared with placebo in patients with acute, non-cardioembolic ischaemic stroke.

FUNDING

Bayer AG.

Abstract 11: Cardiac CT To Detect Cardiac Thrombi In Patients With Acute Ischemic Stroke: A Substudy Of Mind The Heart

Background: Cardiac thrombi are a major risk factor for ischemic stroke. We used cardiac CT to assess the prevalence of cardiac thrombi in acute ischemic stroke patients.

Methods: This was a substudy of Mind the Heart, a prospective single-center cohort study in which consecutive adult patients with acute ischemic stroke underwent prospective ECG-gated cardiac CT during the initial stroke imaging protocol. Patients also underwent routine stroke work-up, including transthoracic echocardiography (TTE). Patients were included from May 2018 to November 2020. We compared patients with a cardiac thrombus on CT (defined as filling defect <100 Hounsfield’s Units) to those without a cardiac thrombus. Outcomes were functional outcome on the modified Rankin scale (mRS) and ischemic stroke recurrence at 90 days.

Results: Of 452 included patients, cardiac CT detected 40 thrombi in 38 (8%) patients. Thrombi were located in the left atrial appendage in 31 (7%), left atrium in 2 (0.4%) and left ventricle in 7 (2%) patients. TTE, performed in 25 patients with a cardiac thrombus (median time CT to TTE 1 day), detected a thrombus in 2 patients (0.4%, both left ventricle thrombi). Patients with a cardiac thrombus more frequently had a history of atrial fibrillation (40% vs 15%), used anticoagulation (42% vs 16%), had a large vessel occlusion (58% vs 41%), had intracranial occlusions in multiple vascular territories (5% vs 0.5%) and had a higher baseline NIHSS (17 [IQR 6-22] vs 5 [IQR 2-3]). In total, 26/38 (68%) patients with a cardiac thrombus had a history of atrial fibrillation or had atrial fibrillation diagnosed during stroke work-up. At 90 days, 19/23 (83%) patients with a cardiac thrombus who were alive were treated with anticoagulation. Patients with a cardiac thrombus had worse functional outcome (median mRS 4 [IQR 2-6] vs 2 [IQR 1-4], p<0.01) and non-significantly more often had a recurrent ischemic stroke (8% vs 5%,p=0.61) than patients without a cardiac thrombus.

Conclusion: Cardiac CT detected a cardiac thrombus in 1 in every 12 patients with acute ischemic stroke. These thrombi were rarely detected with TTE. Patients with cardiac thrombi more often had atrial fibrillation and severe neurological deficits. Functional outcome was worse in patients with cardiac thrombi.

The development of a novel functional food: bioactive lipids in yogurts enriched with Aurantiochytrium sp. biomass

Western diets are poor in healthy n3 polyunsaturated fatty acids, such as docosahexaenoic acid. Since microalga Aurantiochytrium sp. is rich in docosahexaenoic acid, a functional food based on lean yogurt and this microalga was tested. This study entailed characterizing the lipid fraction and determining the fatty acid bioaccessibility. The tested yogurts (control and 2% w/w, Aurantiochytrium sp.) had differences. Docosahexaenoic acid was not detected in the control product, but it was the second most important fatty acid in Aurantiochytrium sp. and Aurantiochytrium yogurt, 29.7 ± 0.4% and 18.7 ± 2.0%, respectively. Based on the fatty acid profile only, an amount of 158.7 g of Aurantiochytrium yogurt in wet weight terms would be required to ensure an appropriate intake of healthy fatty acids. Generally, the fatty acid bioaccessibility was not high, remaining below 60-70% in almost all cases. Considering the docosahexaenoic acid bioaccessibility (44 ± 3%), an amount of 360.7 g of Aurantiochytrium yogurt would be advisable. A reasonable dietary prescription would be a daily consumption of 125 ml of Aurantiochytrium yogurt.

Direct oral anticoagulants in treatment of cerebral venous thrombosis: a systematic review

OBJECTIVES

Current guidelines do not recommend direct oral anticoagulants (DOACs) to treat cerebral venous thrombosis (CVT) despite their benefits over standard therapy. We performed a systematic review to summarise the published experience of DOAC therapy in CVT.

DATA SOURCES

MEDLINE, Embase and COCHRANE databases up to 18 November 2020.

ELIGIBILITY CRITERIA

All published articles of patients with CVT treated with DOAC were included. Studies without follow-up information were excluded.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers screened articles and extracted data. A risk of bias analysis was performed.

PRIMARY AND SECONDARY OUTCOME MEASURES

Safety data included mortality, intracranial haemorrhage (ICH) or other adverse events. Efficacy data included recurrent CVT, recanalisation rates and disability by modified Rankin Scales (mRS).

RESULTS

33 studies met inclusion criteria. One randomised controlled trial, 5 observational cohorts and 27 case series or studies reported 279 patients treated with DOAC for CVT: 41% dabigatran, 47% rivaroxaban, 10% apixaban and 2% edoxaban, in addition to 315 patients treated with standard therapy. The observational cohorts showed a similar risk of death in DOAC and standard therapy arms (RR 2.12, 95% CI 0.29 to 15.59). New ICH was reported in 2 (0.7%) DOAC-treated patients and recurrent CVT occurred in 4 (1.5%). A favourable mRS between 0 and 2 was reported in 94% of DOAC-treated patients, more likely than standard therapy in observational cohorts (RR 1.13, 95% CI 1.02 to 1.25).

CONCLUSION

The evidence for DOAC use in CVT is limited although suggests sufficient safety and efficacy despite variability in timing and dose of treatment. This systematic review highlights that further rigorous trials are needed to validate these findings and to determine optimal treatment regimens.

Predicted Position Error Triggers Catch-Up Saccades during Sustained Smooth Pursuit

For humans, visual tracking of moving stimuli often triggers catch-up saccades during smooth pursuit. The switch between these continuous and discrete eye movements is a trade-off between tolerating sustained position error (PE) when no saccade is triggered or a transient loss of vision during the saccade due to saccadic suppression. de Brouwer et al. (2002b) demonstrated that catch-up saccades were less likely to occur when the target re-crosses the fovea within 40-180 ms. To date, there is no mechanistic explanation for how the trigger decision is made by the brain. Recently, we proposed a stochastic decision model for saccade triggering during visual tracking (Coutinho et al., 2018) that relies on a probabilistic estimate of predicted PE (PEpred). Informed by model predictions, we hypothesized that saccade trigger time length and variability will increase when pre-saccadic predicted errors are small or visual uncertainty is high (e.g., for blurred targets). Data collected from human participants performing a double step-ramp task showed that large pre-saccadic PEpred (>10°) produced short saccade trigger times regardless of the level of uncertainty while saccade trigger times preceded by small PEpred (<10°) significantly increased in length and variability, and more so for blurred targets. Our model also predicted increased signal-dependent noise (SDN) as retinal slip (RS) increases; in our data, this resulted in longer saccade trigger times and more smooth trials without saccades. In summary, our data supports our hypothesized predicted error-based decision process for coordinating saccades during smooth pursuit.

[Late endovascular treatment of acute ischemic stroke]

Late endovascular treatment of acute ischemic stroke Endovascular treatment (EVT) has become the standard of care for patients with acute ischemic stroke (AIS) due to large-vessel occlusion of the anterior circulation within 6 hours after the onset of symptoms. The recently published DAWN and DEFUSE 3 trials have shown that EVT is also effective beyond 6 hours after the onset of symptoms in patients who have been selected on the basis of CT perfusion imaging. We describe three cases of patients in whom we considered 'late' EVT on the basis of the results of these trials. Two female patients, 56 and 66 years old, both with large hemispheric AIS, were treated with EVT, respectively 8 and 15 hours after the onset of symptoms. Both patients had good clinical outcomes. In the third patient, a 79-year-old male, we decided to refrain from treatment with EVT on the basis of CT perfusion imaging. We describe our considerations with respect to these treatment decisions, our interpretation of the results of the DAWN and DEFUSE 3 trials and the implications of these results for the organization of stroke logistics in the Netherlands.

Capacitive technologies for highly controlled and personalized electrical stimulation by implantable biomedical systems

Cosurface electrode architectures are able to deliver personalized electric stimuli to target tissues. As such, this technology holds potential for a variety of innovative biomedical devices. However, to date, no detailed analyses have been conducted to evaluate the impact of stimulator architecture and geometry on stimuli features. This work characterizes, for the first time, the electric stimuli delivered to bone cellular tissues during in vitro experiments, when using three capacitive architectures: stripped, interdigitated and circular patterns. Computational models are presented that predict the influence of cell confluence, cosurface architecture, electrodes geometry, gap size between electrodes and power excitation on the stimuli delivered to cellular layers. The results demonstrate that these stimulators are able to deliver osteoconductive stimuli. Significant differences in stimuli distributions were observed for different stimulator designs and different external excitations. The thickness specification was found to be of utmost importance. In vitro experiments using an osteoblastic cell line highlight that cosurface stimulation at a low frequency can enhance osteoconductive responses, with some electrode-specific differences being found. A major feature of this type of work is that it enables future detailed analyses of stimuli distribution throughout more complex biological structures, such as tissues and organs, towards sophisticated biodevice personalization.

Abstract TP423: Risk Factors for Intracranial Hemorrhage in Cerebral Venous Thrombosis

Cerebral venous thrombosis is associated with intracranial hemorrhage. The occurrence of brain bleeding complicates management and is associated with worse outcomes. We aimed to identify clinical and imaging risk factors for intracerebral hemorrhage. We hypothesized that higher clot burden would be associated with a higher risk of intracerebral hemorrhage.

Methods: We performed a retrospective analysis of an international, multicenter cohort of patients with cerebral venous thrombosis who underwent CT within 2 weeks of symptom onset and who had a subsequent confirmed diagnosis of CVT on MRV, CTV or DSA. Clinical and imaging features were compared between patients with and without intracranial hemorrhage. Clot burden was assessed by counting the number of thrombosed venous sinuses and veins on confirmatory imaging.

Results: We recruited 260 patients with cerebral venous thrombosis from 10 institutions in Europe and Mexico. The mean age was 42 and 74% were female. Intracranial hemorrhage was found in 102 (39%). Intracerebral hemorrhage occurred in 64 (63%), small juxtacortical hemorrhage in 30 (29%), subarachnoid hemorrhage in 24 (24%) and subdural hemorrhage in 11 (11%). Combinations of these types of hemorrhage occurred in 23 (23%). Intraparenchymal hemorrhages in multiple locations occurred in 6 (6%). Older age, presence of hematological disease and superior sagittal thrombosis involvement were significantly associated with presence of hemorrhage. The number of thrombosed venous sinuses was not associated with intracerebral hemorrhage (average number of sinuses/veins involved with hemorrhage 2.1 versus 1.9 without hemorrhage, p=0.4).

Conclusion: The high rate of intracranial hemorrhage in cerebral venous thrombosis is not explained by widespread involvement of the venous sinuses. Superior sagittal sinus involvement is associated with the presence of intracranial hemorrhage.

Adsorption of H2, O2, H2O, OH and H on monolayer MoS2

Hydrogen and hydrogen-containing gases are commonly used as reductants in chemical vapor deposition growth of MoS₂. Here, we consider the defects resulting from the presence of hydrogen during growth and the resulting electronically active defects. In particular, we find that the interstitial hydrogen defect is a negative-U center with amphoteric donor and acceptor properties. Additionally, we consider the effects of interaction with water and oxygen. The defects are analysed using density functional theory calculations.

Abstract WP2: Trends of Endovascular Treatment in Cerebral Venous Thrombosis: Estimations From Nationwide Inpatient Sample

Background and purpose: Although Anticoagulation remains the mainstay of treatment after cerebral venous thrombosis (CVT), 15% of patients may not respond. Evidence of endovascular treatment (ET) in CVT remains limited to case reports. The Nationwide Inpatient Sample (NIS), the largest all-payer inpatient health care database in the United States, represents a 20% stratified sample of community hospitals and approximately 7 million annual hospital admissions. We aimed to evaluate the trends of ET using NIS.

Methods: We extracted data from the NIS between 2004- 2013. CVT patients were identified through ICD 9-CM codes: 437.6, 325 and 671.5. Mechanical thrombectomy (MT) and/or thrombolysis were searched using ICD 9 (CPT) codes 39.74 for Endovascular removal of obstruction from head and neck vessel(s) and 99.10 for any injection or infusion of thrombolytic agent. We compared categorical variables using chi-squared tests and continuous variables with Student t test or Wilcoxon rank-sum tests as indicated. Trends were assessed using a Cochran-Armitage test.

Results: Of 8,891 cases of CVT (un-weighted count), 8676 (98%) cases received only medical management. When the weights were applied, total CVT cases were 42,889. 215 (2%) patients (un-weighted count) received ET. Weighted estimates for ET was 1058. 50 (23%) patients received MT and thrombolysis (weighted 248), 38 (18%) patients received MT alone (weighted 194) and 127 (59%) patients received thrombolysis alone (weighted 616). There was a significantly increasing trend of utilization of the MT over thrombolysis alone over the years (Figure 1).

Conclusion: There is a significant rise in the number of ET cases for CVT over the years, with a trend favoring towards MT over thrombolysis alone.

Abstract WP11: Use of Endovascular Thrombolysis or Thrombectomy for the Treatment of Cerebral Venous Thrombosis: An Observational Study From the US Nationwide Inpatient Sample

Background: Anticoagulation is considered the first-line treatment for cerebral venous thrombosis (CVT). However, a subset of patients does not respond. Data from case studies suggest endovascular treatment (ET) may be beneficial in such cases. The Nationwide Inpatient Sample (NIS), representing a 20% stratified sample of 7 million annual hospital admissions was used to evaluate the safety and efficacy of ET compared to conservative management in CVT.

Methods: We extracted cases from NIS database for years 2004-2013 using ICD 9-CM codes: 437.6, 325, and 671.5. Data related to mechanical thrombectomy (MT) and/or thrombolysis was searched using ICD 9 CPT codes 39.74 and 99.10. Weights were applied to each admission per NIS recommendations to obtain national representation. Groups were matched with respect to age, gender and Charlson index. Data was further adjusted for injury severity score (presence of ICH, stroke, paralysis, midline shift, coma, status epilepticus or need for intubation).

Results: Out of 42,889 weighted estimates of CVT cases, 1058 (2%) received ET (616 cases of thrombolysis alone and 442 cases of MT +/- thrombolysis). Patients who received ET were slightly older with higher comorbidity score, and CVT associated complications including ischemic stroke, ICH, coma, status epilepticus, cerebral edema with midline shift and need for endotracheal intubation. Patients who received ET had higher likelihood of having hematological disorders and severe dehydration and lesser likelihood of infection and trauma as underlying etiology of the condition. ET (thrombolysis alone and mechanical thrombectomy +/- thrombolysis) appeared to be significantly associated mortality and bad discharge outcomes in stepwise logistic regression analyses as well as matched paired analyses (Table 1).

Conclusion: ET appears to be associated with increased mortality and poor discharge outcomes when compared to conservative treatment in the real-world setting.

Psychophysiological Reactivity in Couples During a Marital Interaction Task

The ability to regulate our own physiological arousal when dealing with the emotional expression of our partner is crucial for satisfactory and stable intimate relationships. In previous physiological studies of marital interactions, researchers have found greater levels of psychophysiological arousal for members of the couple in conflictual interactions in comparison with positive interactions. Past researchers have established that intense and prolonged autonomic and neuroendocrine arousal during marital conflict can have negative consequences for mental and physical health. In this study we examined the physiological reactivity, as measured by skin conductance level, heart rate and cortisol levels, from both partners during a couple's interaction task consisting of a structured conversation about positive and negative aspects of their relationship. Participants were thirty-two heterosexual couples (N = 64) in a committed monogamous relationship with a minimum duration of one year. We found higher heart rate and cortisol levels during negative interaction condition when compared with the positive condition. Skin conductance was higher in the positive interaction condition, when compared with the negative interaction condition. In addition, we found a significant negative association between heart rate variability and autonomic arousal evoked by the interaction task. The implications of these findings for the effects of marital strain on health as well as for the design of risk-reducing interventions, namely biofeedback are discussed.

Successful mechanical thrombectomy in a comatose patient with cerebral venous sinus thrombosis: A case report

Cerebral venous sinus thrombosis is a rare cause of stroke, which is routinely treated with systemic heparin. Unfavourable outcome is often seen in severe cases. Therefore alternative treatment methods should be explored in these patients. Due to the risk of haemorrhagic complications, treatment without administration of thrombolytics is of particular interest. This report presents a case of successful mechanical thrombectomy, without the use of thrombolytics, in a comatose patient with cerebral venous sinus thrombosis.

A first-principles model of copper-boron interactions in Si: implications for the light-induced degradation of solar Si

The recent discovery that Cu contamination of Si combined with light exposure has a significant detrimental impact on carrier life-time has drawn much concern within the solar-Si community. The effect, known as the copper-related light-induced degradation (Cu-LID) of Si solar cells, has been connected to the release of Cu interstitials within the bulk (2016 Sol. Energy Mater. Sol. Cells 147 115-26). In this paper, we describe a comprehensive analysis of the formation/dissociation process of the CuB pair in Si by means of first-principles modelling, as well as the interaction of CuB defects with photo-excited minority carriers. We confirm that the long-range interaction between the [Formula: see text] cation and the [Formula: see text] anion has a Coulomb-like behaviour, in line with the trapping-limited diffusivity of Cu observed by transient ion drift measurements. On the other hand, the short-range interaction between the d-electrons of Cu and the excess of negative charge on [Formula: see text] produces a repulsive effect, thereby decreasing the binding energy of the pair when compared to the ideal point-charge Coulomb model. We also find that metastable CuB pairs produce acceptor states just below the conduction band minimum, which arise from the Cu level emptied by the B acceptor. Based on these results, we argue that photo-generated minority carriers trapped by the metastable pairs can switch off the Coulomb interaction that holds the pairs together, enhancing the release of Cu interstitials, and acting as a catalyst for Cu-LID.

Abstract 108: Additional Value of Intracranial Vessel Wall Imaging to Determine the Etiology of Ischemic Stroke

Objective: High-resolution MR-imaging of the intracranial arterial wall is a promising technique for diagnosis of intracranial arteriopathies in patients with ischemic stroke. We aimed to evaluate the additional value of vessel wall imaging (VWI) to the standard work-up of ischemic stroke patients.

Methods: We selected all patients with ischemic stroke who had intracranial VWI at our institute to evaluate possible intracranial arteriopathy, such as atherosclerosis, dissection, vasculitis, or reversible cerebral vasoconstriction syndrome. Two observers, who were blinded to the VWI, first determined the most likely stroke etiology based on the standard work-up (clinical history, brain parenchyma imaging, vessel lumen imaging, laboratory results, and cardiac work-up). Then VWI was reviewed to assess whether this would change the suspected stroke etiology or whether the differential diagnosis could be narrowed down.

Results: Between 2006 and 2014, 199 patients with ischemic stroke, mean age 55 (IQ-range: 44-67) had VWI. VWI provided additional information to the standard stroke work-up in 128 patients (64%). In 38/199 patients (19%) the conclusion on stroke etiology was altered based on VWI and in 90/199 patients (45%) the differential diagnosis was further narrowed after VWI. VWI did not have additional value when the most likely stroke etiology based on the standard work-up remained the same (50/199 patients; 25%), when the differential diagnosis could not be narrowed down (16/199; 8%), or in case of poor image quality (5/199 patients; 3%). Patients under the age of 46 benefited more often from VWI than older adults (Odds Ratio 3.5; 95%CI: 1.7-7.6).

Conclusion: VWI provided additional information to the conventional stroke work-up in almost two-thirds of patients suspected to have intracranial arteriopathy. Next step is to determine how frequently this additional information resulted in altered therapy.

Animal Slurry Acidification Affects Particle Size Distribution and Improves Separation Efficiency

Solid-liquid separation is performed to improve slurry management, and acidification of the slurry is used to reduce ammonia emissions. Acidification is known to affect slurry characteristics, and we hypothesized that it may affect mechanical separation. Our objective in this study was to assess the effects of slurry acidification on particle size distribution and separation efficiency. Two types of slurry, aged pig and fresh dairy, and two different acidification additives, sulfuric acid and aluminum sulfate (alum), were studied. We found that acidification with sulfuric acid promoted phosphorus (P) solubilization for both slurries, but no change was observed with alum. More ammonium was found in the acidified dairy slurry compared with raw dairy slurry, but no difference was found in aged pig slurry. Acidification before separation increased the proportion of the solid fraction in the slurries, and the effect was significantly higher with alum. When alum was used to acidify the slurries, the proportion of particles larger than 100 μm increased significantly, as did the P concentration in this particle size range. The efficiency of P separation increased markedly in both slurries when alum was used, with the removal to the solid fraction of the dairy slurry being almost complete (90%). Because the priority in mechanical separation is to increase the P content in the solid fraction, the use of alum before centrifugation may be the most suitable option for enhancing its nutrient content. We conclude that separation efficiency and particle size distribution are significantly affected by acidification, but the extent of the effects depends on slurry type and on the type of additive used for acidification.

Embolic strokes of undetermined source: Prevalence and patient features in the ESUS Global Registry

Background

Recent evidence supports that most non-lacunar cryptogenic strokes are embolic. Accordingly, these strokes have been designated as embolic strokes of undetermined source (ESUS).

Aims

We undertook an international survey to characterize the frequency and clinical features of ESUS patients across global regions.

Methods

Consecutive patients hospitalized for ischemic stroke were retrospectively surveyed from 19 stroke research centers in 19 different countries to collect patients meeting criteria for ESUS.

Results

Of 2144 patients with recent ischemic stroke, 351 (16%, 95% CI 15% to 18%) met ESUS criteria, similar across global regions (range 16% to 21%), and an additional 308 (14%) patients had incomplete evaluation required for ESUS diagnosis. The mean age of ESUS patients (62 years; SD = 15) was significantly lower than the 1793 non-ESUS ischemic stroke patients (68 years, p ≤ 0.001). Excluding patients with atrial fibrillation ( n = 590, mean age = 75 years), the mean age of the remaining 1203 non-ESUS ischemic stroke patients was 64 years ( p = 0.02 vs. ESUS patients). Among ESUS patients, hypertension, diabetes, and prior stroke were present in 64%, 25%, and 17%, respectively. Median NIHSS score was 4 (interquartile range 2–8). At discharge, 90% of ESUS patients received antiplatelet therapy and 7% received anticoagulation.

Conclusions

This cross-sectional global sample of patients with recent ischemic stroke shows that one-sixth met criteria for ESUS, with additional ESUS patients likely among those with incomplete diagnostic investigation. ESUS patients were relatively young with mild strokes. Antiplatelet therapy was the standard antithrombotic therapy for secondary stroke prevention in all global regions.

Impact of slurry management strategies on potential leaching of nutrients and pathogens in a sandy soil amended with cattle slurry

For farmers, management of cattle slurry (CS) is now a priority, in order to improve the fertilizer value of the slurry and simultaneously minimize its environmental impact. Several slurry pre-treatments and soil application methods to minimize ammonia emissions are now available to farmers, but the impact of such management strategies on groundwater is still unclear. A laboratory experiment was performed over 24 days in controlled conditions, with undisturbed soil columns (sandy soil) in PVC pipes (30 cm high and 5.7 cm in diameter). The treatments considered (4 replicates) were: a control with no amendment (CTR), injection of whole CS (WSI), and surface application of: whole CS (WSS), acidified (pH 5.5) whole CS (AWSS), the liquid fraction obtained by centrifugation of CS (LFS), and acidified (pH 5.5) liquid fraction (ALFS). An amount of CS equivalent to 240 kg N ha(-1) was applied in all treatments. The first leaching event was performed 72 h after application of the treatments and then leaching events were performed weekly to give a total of four irrigation events (IEs). All the leachates obtained were analyzed for mineral and organic nitrogen, electrical conductivity (EC), pH, total carbon, and phosphorus. Total coliforms and Escherichia coli were also quantified in the leachates obtained in the first IE. The results show that both acidification and separation had significant effects on the composition of the leachates: higher NO3(-) concentrations were observed for the LFS and ALFS relative to all the other treatments, throughout the experiment, and lower NO3(-) concentrations were observed for acidified relative to non-acidified treatments at IE2. Acidification of both the LF and WS led to higher NH4(+) concentrations as well as an increase of EC for treatment ALFS relative to the control, in the first IE, and lower pH values in the AWSS. Furthermore, the E. coli and total coliform concentrations in AWSS, LFS, and ALFS were significantly higher than in WSI or WSS. In conclusion, none of the strategies generally used to minimize ammonia emissions impact positively on leaching potential relative to the traditional surface application of CS. Furthermore, some treatments, such as separation, might increase significantly the risk of leaching.

Anti-N-methyl-D-aspartate receptor encephalitis in a pre-teenage girl: a case report

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is an auto-immune and paraneoplastic encephalitis which generally affects young adults. It is a multistage illness, with prominent extrapyramidal, neuropsychiatric and autonomic symptoms. The syndrome is frequently associated with an ovarian teratoma. Recently, it has become evident that anti-NMDAR encephalitis is more common in children and adolescents than was previously believed. Prognostic factors that determine a good outcome are presence of a tumour, prompt treatment and no need for admission to an intensive care unit. Increased awareness among paediatricians of this potentially life-threatening disease is important because early recognition and treatment will improve the patients' chances of a good clinical outcome. In this case report, we describe a 9-year-old girl with behavioural changes and severe extrapyramidal symptoms due to anti-NMDAR encephalitis associated with an ovarian teratoma. She was treated with a variety of immunomodulating therapies and made a slow, but good recovery.

Strain-induced structure transformations on Si(111) and Ge(111) surfaces: a combined density-functional and scanning tunneling microscopy study

Si(111) and Ge(111) surface formation energies were calculated using density functional theory for various biaxial strain states ranging from -0.04 to 0.04, and for a wide set of experimentally observed surface reconstructions: 3 × 3, 5 × 5, 7 × 7 dimer-adatom-stacking fault reconstructions and c(2 × 8), 2 × 2, and √3×√3 adatoms based surfaces. The calculations are compared with scanning tunneling microscopy data obtained on stepped Si(111) surfaces and on Ge islands grown on a Si(111) substrate. It is shown that the surface structure transformations observed in these strained systems are accounted for by a phase diagram that relates the equilibrium surface structure to the applied strain. The calculated formation energy of the unstrained Si(111)-9 × 9 dimer-adatom-stacking fault surface is reported for the first time and it is higher than corresponding energies of Si(111)-5 × 5 and Si(111)-7 × 7 dimer-adatom-stacking fault surfaces as expected. We predict that the Si(111) surface should adopt a c(2 × 8) reconstruction when tensile strain is above 0.03.

Simple technologies for on-farm composting of cattle slurry solid fraction

Composting technologies and control systems have reached an advanced stage of development, but these are too complex and expensive for most agricultural practitioners for treating livestock slurries. The development of simple, but robust and cost-effective techniques for composting animal slurries is therefore required to realise the potential benefits of waste sanitation and soil improvement associated with composted livestock manures. Cattle slurry solid fraction (SF) was collected at the rates of 4m(3)h(-1) and 1m(3)h(-1) and composted in tall (1.7 m) and short (1.2m) static piles, to evaluate the physicochemical characteristics and nutrient dynamics of SF during composting without addition of bulking agent materials, and without turning or water addition. Highest maximum temperatures (62-64 °C) were measured in tall piles compared to short piles (52 °C). However, maximum rates of organic matter (OM) destruction were observed at mesophilic temperature ranges in short piles, compared to tall piles, whereas thermophilic temperatures in tall piles maximised sanitation and enhanced moisture reduction. Final OM losses were within the range of 520-660 g kg(-1) dry solids and the net loss of OM significantly (P<0.001) increased nutrient concentrations during the composting period. An advanced degree of stabilization of the SF was indicated by low final pile temperatures and C/N ratio, low concentrations of NH(4)(+) and increased concentrations of NO(3)(-) in SF composts. The results indicated that minimum intervention composting of SF in static piles over 168 days can produce agronomically effective organic soil amendments containing significant amounts of OM (772-856 g kg(-1)) and plant nutrients. The implications of a minimal intervention management approach to composting SF on compost pathogen reduction are discussed and possible measures to improve sanitation are suggested.

Anticoagulation for cerebral venous sinus thrombosis

BACKGROUND

Treatment of cerebral venous sinus thrombosis with anticoagulants has been controversial. Anticoagulants may prevent new venous infarcts, neurologic deterioration and pulmonary embolism but may also promote haemorrhages.

OBJECTIVES

To assess the effectiveness and safety of anticoagulant therapy in patients with confirmed cerebral venous sinus thrombosis.

SEARCH STRATEGY

We searched the Cochrane Stroke Group Trials Register (last searched August 2010), MEDLINE (1950 to August 2010), EMBASE (1980 to August 2010) and the Cochrane Central Register of Controlled Trials (The Cochrane Library, 2011 Issue 1). In an effort to identify further published, unpublished and ongoing trials we searched ongoing trials registers and reference lists of relevant articles, and contacted authors.

SELECTION CRITERIA

Unconfounded randomised controlled trials in which anticoagulant therapy was compared with placebo or open control in patients with cerebral venous sinus thrombosis (confirmed by intra-arterial contrast, or venography with magnetic resonance, or venography with computed tomography imaging).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted outcomes for each of the two treatment groups (anticoagulant treatment and control). The outcome data for each patient were analysed in the treatment group to which the patient was originally allocated (intention-to-treat analysis). We calculated a weighted estimate of the treatment effects across trials (relative risk, absolute risk reduction).

MAIN RESULTS

We included two small trials involving 79 patients. One trial (20 patients) examined the efficacy of intravenous, adjusted dose unfractionated heparin. The other trial (59 patients) examined high dose, body weight adjusted, subcutaneous, low-molecular weight heparin (nadroparin). Anticoagulant therapy was associated with a pooled relative risk of death of 0.33 (95% confidence interval (CI) 0.08 to 1.21) and of death or dependency of 0.46 (95% CI 0.16 to 1.31). The absolute reduction in the risk of death or dependency was 13% (95% CI 30% to -3%). No new symptomatic intracerebral haemorrhages were observed. One major gastro-intestinal haemorrhage occurred after anticoagulant treatment. Two control patients (placebo) had a diagnosis of probable pulmonary embolism (one fatal).

AUTHORS' CONCLUSIONS

Based upon the limited evidence available, anticoagulant treatment for cerebral venous sinus thrombosis appeared to be safe and was associated with a potentially important reduction in the risk of death or dependency which did not reach statistical significance.

Apoptosis and insulin resistance in liver and peripheral tissues of morbidly obese patients is associated with different stages of non-alcoholic fatty liver disease

AIMS/HYPOTHESIS

Non-alcoholic fatty liver disease (NAFLD) is associated with insulin resistance and characterised by different degrees of hepatic lesion. Its pathogenesis and correlation with apoptosis and insulin resistance in insulin target tissues remains incompletely understood. We investigated how insulin signalling, caspase activation and apoptosis correlate with different NAFLD stages in liver, muscle and visceral adipose tissues.

METHODS

Liver, muscle and adipose tissue biopsies from 26 morbidly obese patients undergoing bariatric surgery were grouped according to the Kleiner-Brunt scoring system into simple steatosis, and less severe and more severe non-alcoholic steatohepatitis (NASH). Apoptosis was assessed by DNA fragmentation, and caspase-2 and -3 activation. Insulin signalling and c-Jun NH(2)-terminal kinase (JNK) proteins were evaluated by western blot.

RESULTS

Caspase-3 and -2 activation, and DNA fragmentation were markedly increased in the liver of patients with severe NASH vs in that of those with simple steatosis (p < 0.01). Muscle tissue, and to a lesser extent the liver, had decreased tyrosine phosphorylated insulin receptor and insulin receptor substrate in patients with severe NASH, compared with those with simple steatosis (p < 0.01 muscle; p < 0.05 liver). Concomitantly, Akt phosphorylation decreased in muscle, liver and visceral adipose tissues in patients with severe NASH (at least p < 0.05). Finally, JNK phosphorylation was significantly increased in muscle (p < 0.01) and liver (p < 0.05) from NASH patients, compared with tissue from those with simple steatosis.

CONCLUSIONS/INTERPRETATION

Our results demonstrate a link between apoptosis, insulin resistance and different NAFLD stages, where JNK and caspase-2 may play a key regulatory role.

Electronic structure of Zn, Cu and Ni impurities in germanium

We present a density functional modelling study of Zn, Cu and Ni impurities in hydrogen-terminated germanium clusters. Their electronic structure is investigated in detail, especially their Jahn-Teller instabilities and electrical levels. Interstitial and substitutional defects were considered and the latter were found to be the most stable defect form for nearly all Fermi level positions. Relative formation energies are estimated semi-empirically with the help of the measured formation energy of the single Ge vacancy. We find that while Zn is a double shallow acceptor, Cu and Ni are deep acceptors with levels close to the available experimental data. Donor levels were only found for interstitial Cu and Zn.

Methods to improve the composting process of the solid fraction of dairy cattle slurry

Cattle slurry solid fraction (SF) with different dry matter (DM) contents was collected from two dairy farms and composted in static and turned piles, with different sizes and cover types, to investigate the effects of pile conditions on the physical and chemical changes in SF during composting and to identify approaches to improve final compost quality. Thermophilic temperatures were attained soon after separation of SF, but the temperature of piles covered with polyethylene did not increase above 60 degrees C. The rate of organic matter (OM) mineralisation increased for turned piles in comparison to static piles, but the maximum amount of mineralisable OM (630-675gkg(-1)) was similar for all pile treatments. The C/N ratio declined from over 36 to a value of 14 towards the end of composting, indicating an advanced degree of OM stabilisation. Mature compost was obtained from raw SF feedstock as indicated by the low compost temperature, low C/N ratio, and low content of NH(4)(+) combined with increased concentrations of NO(3)(-). The efficiency of the composting process was improved and NH(3)-N losses were minimized by increasing DM content of the SF, reducing the frequency of pile turning and managing compost piles without an impermeable cover.

Self-interstitial in germanium

Low-temperature radiation damage in n- and p-type Ge is strikingly different, reflecting the charge-dependent properties of vacancies and self-interstitials. We find, using density functional theory, that in Ge the interstitial is bistable, preferring a split configuration when neutral and an open cage configuration when positively charged. The split configuration is inert while the cage configuration acts as a double donor. We evaluate the migration energies of the defects and show that the theory is able to explain the principal results of low-temperature electron-irradiation experiments.