Tenecteplase versus standard of care for minor ischaemic stroke with proven occlusion (TEMPO-2): a randomised, open label, phase 3 superiority trial.

BACKGROUND: Individuals with minor ischaemic stroke and intracranial occlusion are at increased risk of poor outcomes. Intravenous thrombolysis with tenecteplase might improve outcomes in this population. We aimed to test the superiority of intravenous tenecteplase over non-thrombolytic standard of care in patients with minor ischaemic stroke and intracranial occlusion or focal perfusion abnormality. METHODS: In this multicentre, prospective, parallel group, open label with blinded outcome assessment, randomised controlled trial, adult patients (aged ≥18 years) were included at 48 hospitals in Australia, Austria, Brazil, Canada, Finland, Ireland, New Zealand, Singapore, Spain, and the UK. Eligible patients with minor acute ischaemic stroke (National Institutes of Health Stroke Scale score 0-5) and intracranial occlusion or focal perfusion abnormality were enrolled within 12 h from stroke onset. Participants were randomly assigned (1:1), using a minimal sufficient balance algorithm to intravenous tenecteplase (0·25 mg/kg) or non-thrombolytic standard of care (control). Primary outcome was a return to baseline functioning on pre-morbid modified Rankin Scale score in the intention-to-treat (ITT) population (all patients randomly assigned to a treatment group and who did not withdraw consent to participate) assessed at 90 days. Safety outcomes were reported in the ITT population and included symptomatic intracranial haemorrhage and death. This trial is registered with ClinicalTrials.gov, NCT02398656, and is closed to accrual. FINDINGS: The trial was stopped early for futility. Between April 27, 2015, and Jan 19, 2024, 886 patients were enrolled; 369 (42%) were female and 517 (58%) were male. 454 (51%) were assigned to control and 432 (49%) to intravenous tenecteplase. The primary outcome occurred in 338 (75%) of 452 patients in the control group and 309 (72%) of 432 in the tenecteplase group (risk ratio [RR] 0·96, 95% CI 0·88-1·04, p=0·29). More patients died in the tenecteplase group (20 deaths [5%]) than in the control group (five deaths [1%]; adjusted hazard ratio 3·8; 95% CI 1·4-10·2, p=0·0085). There were eight (2%) symptomatic intracranial haemorrhages in the tenecteplase group versus two (<1%) in the control group (RR 4·2; 95% CI 0·9-19·7, p=0·059). INTERPRETATION: There was no benefit and possible harm from treatment with intravenous tenecteplase. Patients with minor stroke and intracranial occlusion should not be routinely treated with intravenous thrombolysis. FUNDING: Heart and Stroke Foundation of Canada, Canadian Institutes of Health Research, and the British Heart Foundation.

Neuropathological spectrum of anti-IgLON5 disease and stages of brainstem tau pathology: updated neuropathological research criteria of the disease-related tauopathy.

Anti-IgLON5 disease is a unique condition that bridges autoimmunity and neurodegeneration. Since its initial description 10 years ago, an increasing number of autopsies has led to the observation of a broader spectrum of neuropathologies underlying a particular constellation of clinical symptoms. In this study, we describe the neuropathological findings in 22 patients with anti-IgLON5 disease from 9 different European centers. In 15 patients (68%), we observed a hypothalamic and brainstem-predominant tauopathy of varying severity in which the original research neuropathological criteria were readily applicable. This pathology was observed in younger patients (median age at onset 61 years) with a long disease duration (median 9 years). In contrast, in 7 (32%) patients, the originally described brainstem tauopathy was nearly absent or only minimal in the form of delicate threads, despite mild-to-moderate neurodegenerative features, consistent clinical symptoms and the presence of anti-IgLON5 antibodies in CSF and serum. These patients were older at onset (median 79 years) and had shorter disease duration (median < 1 year). Overall, about one-third of the patients showed concomitant TDP-43 pathology within the regions affected by tau pathology and/or neurodegeneration. Based on these observations and in view of the spectrum of the tau burden in the core regions involved in the disease, we propose a simple staging system: stage 1 mild neurodegeneration without overt or only minimal tau pathology, stage 2 moderate neurodegeneration and mild/ moderate tauopathy and stage 3 prominent neurodegeneration and tau pathology. This staging intends to reflect a potential (age- and time-dependent) progression of tau pathology, supporting the current notion that tau accumulation is a secondary phenomenon related to the presence of anti-IgLON5 antibodies in the CNS. Finally, we adapt the original research criteria of the anti-IgLON5 disease-related tauopathy to include the spectrum of pathologies observed in this larger postmortem series.

Pre-hospital and intrahospital workflow optimization for patients with suspected ischemic stroke due to large vessel occlusion - findings from a tertiary care facility.

BACKGROUND: The efficacy of recanalization treatment in patients with ischemic stroke due to large vessel occlusion (LVO) is highly time dependent. We aimed to investigate the effects of an optimization of prehospital and intrahospital pathways on time metrics and efficacy of endovascular treatment in ischemic stroke due to LVO. METHODS: Patients treated with mechanical thrombectomy (MT) at the Hospital of St. John of God Vienna, Austria, between 2013 and 2020 were extracted from the Austrian Stroke Unit Registry. Study endpoints including time metrics, early neurological improvement and functional outcome measured by modified Rankin Scale (mRS) at 3 months were compared before and after optimization of prehospital and intrahospital pathways. RESULTS: Two hundred ninety-nine patients were treated with MT during the study period, 94 before and 205 after the workflow optimization. Workflow optimization was significantly associated with time metrics improvement (door to groin puncture time 45 versus 31 min; p < 0.001), rates of neurological improvement (NIHSS ≥ 8: 30 (35%) vs. 70 (47%), p = 0.04) and radiological outcome (TICI ≥ 2b: 71 (75%) versus 153 (87%); p = 0.013). Functional outcome (mRS 0-2: 17 (18%) versus 57 (28%); p = 0.067) and mortality (34 (37%) versus 54 (32%); p = 0.450) at 3 months showed a non-significant trend in the later time period group. CONCLUSION: The implementation of workflow optimization was associated a significant reduction of intrahospital time delays and improvement of neurological and radiological outcomes.

Long-term outcome of a pragmatic trial of multifaceted intervention (STROKE-CARD care) to reduce cardiovascular risk and improve quality-of-life after ischaemic stroke and transient ischaemic attack: study protocol.

BACKGROUND: Patients with ischaemic stroke or transient ischaemic attack (TIA) are at high risk of incident cardiovascular events and recurrent stroke. Despite compelling evidence about the efficacy of secondary prevention, a substantial gap exists between risk factor management in real life and that recommended by international guidelines. We conducted the STROKE-CARD trial (NCT02156778), a multifaceted pragmatic disease management program between 2014 and 2018 with follow-up until 2019. This program successfully reduced cardiovascular risk and improved health-related quality of life and functional outcome in patients with acute ischaemic stroke or TIA within 12 months after the index event. To investigate potential long-term effects of STROKE-CARD care compared to standard care, an extension of follow-up is warranted. METHODS: We aim to include all patients from the STROKE-CARD trial (n = 2149) for long-term follow-up between 2019 and 2021 with the study visit scheduled 3-6 years after the stroke/TIA event. The co-primary endpoint is the composite of major recurrent cardiovascular events (nonfatal stroke, nonfatal myocardial infarction, and vascular death) from hospital discharge until the long-term follow-up visit and health-related quality of life measured with the European Quality of Life-5 Dimensions (EQ-5D-3L) at the final visit. Secondary endpoints include overall mortality, long-term functional outcome, and target-level achievement in risk factor management. DISCUSSION: This long-term follow-up will provide evidence on whether the pragmatic post-stroke/TIA intervention program STROKE-CARD is capable of preventing recurrent cardiovascular events and improving quality-of-life in the long run. Trial registration clinicaltrials.gov: NCT04205006 on 19 December 2019.

Trends of r-tPA (Recombinant Tissue-Type Plasminogen Activator) Treatment and Treatment-Influencing Factors in Acute Ischemic Stroke.

Background and Purpose- Frequencies of treatment with r-tPA (recombinant tissue-type plasminogen activator) are increasing over the past 15 years. However, published data on the influence of various demographic and clinical factors on r-tPA treatment as well as estimates of future trajectories are limited. We evaluated time trends and future trajectories of r-tPA treatment in patients with acute stroke and the influence of various factors on r-tPA treatment by analyzing data of 103 970 patients enrolled in the Austrian Stroke Unit Registry from 2006 to 2018, of which 18 953 were treated with r-tPA. Methods- Time trends of r-tPA-treatment were investigated in predefined subgroups (minor/major stroke, age, anterior/posterior circulation stroke); limited exponential time series models were calculated to estimate future trends of r-tPA-treatment. Logistic regression models were calculated to estimate the influence of clinical variables on r-tPA-treatment. Results- Overall, r-tPA treatment frequencies increased from 9.9% in 2006 to 21.8% in 2018. We observed a particular increase in patients >80 years, patients presenting with a National Institutes of Health Stroke Scale Score of 2 to 3, patients with posterior circulation stroke, patients with wake-up stroke, and patients without atrial fibrillation. Forecast of overall r-tPA frequencies predicted a further but flattened increase up to 24% by 2025. Logistic regression of time-dependent associations of clinical variables with r-tPA-treatment revealed increasing odds of r-tPA-treatment in patients with a posterior circulation stroke and decreasing odds of r-tPA-treatment in patients with atrial fibrillation. Conclusions- We observed a positive development of r-tPA-treatment frequencies mirroring increasing confidence with intravenous thrombolysis in clinical practice; however, decreasing odds of r-tPA-treatment over time in patients with atrial fibrillation deserve particular attention.

Characteristics and Outcomes in Patients With COVID-19 and Acute Ischemic Stroke: The Global COVID-19 Stroke Registry.

Recent case-series of small size implied a pathophysiological association between coronavirus disease 2019 (COVID-19) and severe large-vessel acute ischemic stroke. Given that severe strokes are typically associated with poor prognosis and can be very efficiently treated with recanalization techniques, confirmation of this putative association is urgently warranted in a large representative patient cohort to alert stroke clinicians, and inform pre- and in-hospital acute stroke patient pathways. We pooled all consecutive patients hospitalized with laboratory-confirmed COVID-19 and acute ischemic stroke in 28 sites from 16 countries. To assess whether stroke severity and outcomes (assessed at discharge or at the latest assessment for those patients still hospitalized) in patients with acute ischemic stroke are different between patients with COVID-19 and non-COVID-19, we performed 1:1 propensity score matching analyses of our COVID-19 patients with non-COVID-19 patients registered in the Acute Stroke Registry and Analysis of Lausanne Registry between 2003 and 2019. Between January 27, 2020, and May 19, 2020, 174 patients (median age 71.2 years; 37.9% females) with COVID-19 and acute ischemic stroke were hospitalized (median of 12 patients per site). The median National Institutes of Health Stroke Scale was 10 (interquartile range [IQR], 4-18). In the 1:1 matched sample of 336 patients with COVID-19 and non-COVID-19, the median National Institutes of Health Stroke Scale was higher in patients with COVID-19 (10 [IQR, 4-18] versus 6 [IQR, 3-14]), P=0.03; (odds ratio, 1.69 [95% CI, 1.08-2.65] for higher National Institutes of Health Stroke Scale score). There were 48 (27.6%) deaths, of which 22 were attributed to COVID-19 and 26 to stroke. Among 96 survivors with available information about disability status, 49 (51%) had severe disability at discharge. In the propensity score-matched population (n=330), patients with COVID-19 had higher risk for severe disability (median mRS 4 [IQR, 2-6] versus 2 [IQR, 1-4], P<0.001) and death (odds ratio, 4.3 [95% CI, 2.22-8.30]) compared with patients without COVID-19. Our findings suggest that COVID-19 associated ischemic strokes are more severe with worse functional outcome and higher mortality than non-COVID-19 ischemic strokes.

Predicting Early Mortality of Acute Ischemic Stroke.

Background and Purpose- Several risk factors are known to increase mid- and long-term mortality of ischemic stroke patients. Information on predictors of early stroke mortality is scarce but often requested in clinical practice. We therefore aimed to develop a rapidly applicable tool for predicting early mortality at the stroke unit. Methods- We used data from the nationwide Austrian Stroke Unit Registry and multivariate regularized logistic regression analysis to identify demographic and clinical variables associated with early (≤7 days poststroke) mortality of patients admitted with ischemic stroke. These variables were then used to develop the Predicting Early Mortality of Ischemic Stroke score that was validated both by bootstrapping and temporal validation. Results- In total, 77 653 ischemic stroke patients were included in the analysis (median age: 74 years, 47% women). The mortality rate at the stroke unit was 2% and median stay of deceased patients was 3 days. Age, stroke severity measured by the National Institutes of Health Stroke Scale, prestroke functional disability (modified Rankin Scale >0), preexisting heart disease, diabetes mellitus, posterior circulation stroke syndrome, and nonlacunar stroke cause were associated with mortality and served to build the Predicting Early Mortality of Ischemic Stroke score ranging from 0 to 12 points. The area under the curve of the score was 0.879 (95% CI, 0.871-0.886) in the derivation cohort and 0.884 (95% CI, 0.863-0.905) in the validation sample. Patients with a score ≥10 had a 35% (95% CI, 28%-43%) risk to die within the first days at the stroke unit. Conclusions- We developed a simple score to estimate early mortality of ischemic stroke patients treated at a stroke unit. This score could help clinicians in short-term prognostication for management decisions and counseling.

Intravenous thrombolysis and mechanical thrombectomy in patients with minor or rapidly improving neurological deficits.

PURPOSE OF REVIEW: A substantial proportion of patients with ischemic stroke present with mild neurological deficits ('Stroke with mild symptoms,' SMS). Treating these patients with thrombolysis or with thrombectomy is controversial and clinical practice is different. We will highlight the importance of these treatment decisions by reviewing the recent advances in this area. RECENT FINDINGS: Intravenous thrombolysis with recombinant tissue plasminogen activator in patients with SMS showed a significant reduction in functional disability after 3 months. Treatment with tenecteplase seems to be a pharmacologically superior and possibly safer thrombolytic agent making it ideal for use in this patient group. Imaging criteria to select the profiting patients are evolving. Thrombectomy in patients with a large vessel occlusion and minor deficits are showing promising results in cohort studies so far, however, randomized controlled trials are lacking. SUMMARY: Patients with acute ischemic stroke and minor or rapidly improving symptoms should be carefully treated the same way as more severe strokes are treated as neurological deterioration is not infrequent. Nevertheless, treatment decisions should be individualized dependent on clinical and radiological features.

Modified DWI-FLAIR mismatch guided thrombolysis in unknown onset stroke.

DWI-FLAIR mismatch has been recently proven to identify patients with unknown onset stroke (UOS) eligible for thrombolysis. However, this concept may exclude patients from thrombolysis who may eventually benefit as well. We aimed to examine the feasibility, safety and potential efficacy of thrombolysis in wake-up stroke (WUS) and UOS patients using a modified DWI-FLAIR mismatch allowing for partial FLAIR positivity. WUS/UOS patients fulfilling the modified DWI-FLAIR mismatch and treated with intravenous thrombolysis (IVT) were compared to propensity score matched WUS/UOS patients excluded from IVT due to FLAIR positivity. The primary endpoint was a symptomatic intracranial hemorrhage (SICH), the secondary endpoints were improvement of ≥ 4 in NIHSS score and mRS score at 3 months. 64 IVT-treated patients (median NIHSS 9) and 64 controls (median NIHSS 8) entered the analysis (p = 0.2). No significant difference in SICH was found between the IVT group and the controls (3.1% vs. 1.6%, p = 0.9). An improvement of ≥ 4 NIHSS points was more frequent in IVT patients as compared to controls (40.6% vs. 18.8%, p = 0.01). 23.4% of IVT patients achieved a mRS score of 0-1 at 3 months as compared to 18.8% of the controls (p = 0.8). SICH, improvement of NIHSS ≥ 4 and mRS 0-1 at 3 months were comparable in thrombolyzed patients with negative FLAIR images versus those thrombolyzed with partial positive FLAIR images (3% vs. 3%, p = 0.9; 40% vs. 41%, p = 0.9; 19% vs. 22%, p = 0.8). Our study signalizes that thrombolysis may be feasible in selected WUS/UOS patients with partial FLAIR signal positivity.

Is Functional Outcome Different in Posterior and Anterior Circulation Stroke?

Background and Purpose- Posterior circulation stroke (PCS) account for 20% of all ischemic strokes. There is limited evidence whether functional outcome of PCS is comparable to that of anterior circulation stroke (ACS). We aimed to analyze whether 3-month functional outcome is different in PCS and ACS. Methods- Patients with acute ischemic stroke prospectively enrolled within the Austrian Stroke Unit Registry were stratified by infarct localization according to the Oxfordshire Community Stroke Project Classification. Propensity score matching was used to control for covariate imbalances and to match patients with PCS and ACS. Patients were matched for stroke severity, recombinant tissue-type plasminogen activator treatment, and demographic and vascular risk factors. Main outcomes were the distribution of modified Rankin Scale after 3 months and multiple proportional odds models to estimate the influence of the infarct localization on the functional outcome. Results- From a total of 90 484 patients enrolled within the Austrian Stroke Unit Registry, 9208 (4604 PCS/4604 ACS) were matched, of those 954 (477 in each group) were treated with recombinant tissue-type plasminogen activator. We detected a significant shift towards better 3-month functional outcome in patients with ACS compared with PCS (odds ratio [OR], 1.19; 95% CI, 1.1-1.28; P<0.0001). In particular, functional outcome was worse in PCS with onset-to-door-time >270 minutes (OR, 1.34; 95% CI, 1.17-1.54; P<0.0001) and in PCS with unknown onset-to-door-time (OR, 1.26; 95% CI, 1.13-1.42; P<0.0001); however, we did not detect any difference in functional outcome between ACS and PCS in patients with an onset-to-door-time ≤270 minutes (1-180 minutes: OR, 0.92, 95% CI, 0.78-1.09, P=0.3554; 181-270 minutes: OR, 1.04, 95% CI, 0.79-1.37, P=0.7689). In patients treated with recombinant tissue-type plasminogen activator, functional outcome was not significantly different between PCS and ACS. Conclusions- PCS was associated with worse outcome compared with ACS in patients arriving later than 4.5 hours at hospital or in those with unknown onset of symptoms. Our results urge for implementation of symptoms found in the posterior circulation into preclinical patient-triage tools.

Pragmatic trial of multifaceted intervention (STROKE-CARD care) to reduce cardiovascular risk and improve quality-of-life after ischaemic stroke and transient ischaemic attack -study protocol.

BACKGROUND: Patients with ischaemic stroke or transient ischaemic attack (TIA) are at high risk of future cardiovascular events. Despite compelling evidence about the efficacy of secondary prevention, a substantial gap exists between risk factor management in real life and that recommended by international guidelines. Moreover, stroke is a leading cause of disability and morbidity which partly emerges from post-stroke complications. METHODS/DESIGN: We designed a block-randomised (2:1 ratio) open pragmatic trial [NCT02156778] with blinded outcome assessment comparing STROKE-CARD to usual post-stroke-patient care. STROKE-CARD is a multifaceted post-stroke disease management program with the objective of reducing recurrent cardiovascular events and improving quality of life in ischaemic stroke and TIA-patients. It combines intensified multi-domain secondary prevention, systematic detection and treatment of post-stroke complications, and patient self-empowerment. Enrolment of 2160 patients with acute ischaemic stroke or TIA (ABCD2-Score ≥ 3) is planned at two study centres in Austria. The co-primary efficacy endpoints are (i) the composite of major recurrent cardiovascular events (nonfatal stroke, nonfatal myocardial infarction, and vascular death) occurring within 12 months after the index event and (ii) one-year health-related quality-of-life measured with the European Quality of Life-5 Dimensions (EQ-5D-3 L) questionaire. Secondary endpoints include all-cause mortality, functional outcome, and target-level achievement in risk factor management. DISCUSSION: This trial will provide evidence on whether the pragmatic post-stroke intervention program STROKE-CARD can help prevent cardiovascular events and improve quality-of-life within the setting of a high-quality acute stroke care system. In case of success, STROKE-CARD may be implemented in daily clinical routine and serve as a model for other disease management initiatives. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02156778 . (June 5, 2014, retrospectively registered).

Do Women With Atrial Fibrillation Experience More Severe Strokes? Results From the Austrian Stroke Unit Registry.

BACKGROUND AND PURPOSE: Ischemic strokes associated with atrial fibrillation (AF) are more severe than those of other cause. We aim to study potential sex effects in this context. METHODS: In this cross-sectional study, 74 425 adults with acute ischemic stroke from the Austrian Stroke Unit Registry were included between March 2003 and January 2016. In 63 563 patients, data on the National Institutes of Health Stroke Scale on admission to the stroke unit, presence of AF, vascular risk factors, and comorbidities were complete. Analysis was done by a multivariate regression model. RESULTS: Stroke severity in general increased with age. AF-related strokes were more severe than strokes of other causes. Sex-related differences in stroke severity were only seen in stroke patients with AF. Median (Q25,75) National Institutes of Health Stroke Scale score points were 9 (4,17) in women and 6 (3,13) in men (P<0.001). The interaction between AF and sex on stroke severity was independent of age, previous functional status, vascular risk factors, and vascular comorbidities and remained significant in various subgroups. CONCLUSIONS: Women with AF do not only have an increased risk of stroke when compared with men but also experience more severe strokes.

Targeted re-sequencing confirms the importance of chemosensory genes in aphid host race differentiation.

Host-associated races of phytophagous insects provide a model for understanding how adaptation to a new environment can lead to reproductive isolation and speciation, ultimately enabling us to connect barriers to gene flow to adaptive causes of divergence. The pea aphid (Acyrthosiphon pisum) comprises host races specializing on legume species and provides a unique system for examining the early stages of diversification along a gradient of genetic and associated adaptive divergence. As host choice produces assortative mating, understanding the underlying mechanisms of choice will contribute directly to understanding of speciation. As host choice in the pea aphid is likely mediated by smell and taste, we use capture sequencing and SNP genotyping to test for the role of chemosensory genes in the divergence between eight host plant species across the continuum of differentiation and sampled at multiple locations across western Europe. We show high differentiation of chemosensory loci relative to control loci in a broad set of pea aphid races and localities, using a model-free approach based on principal component analysis. Olfactory and gustatory receptors form the majority of highly differentiated genes and include loci that were already identified as outliers in a previous study focusing on the three most closely related host races. Consistent indications that chemosensory genes may be good candidates for local adaptation and barriers to gene flow in the pea aphid open the way to further investigations aiming to understand their impact on gene flow and to determine their precise functions in response to host plant metabolites.

Dynamics of copy number variation in host races of the pea aphid.

Copy number variation (CNV) makes a major contribution to overall genetic variation and is suspected to play an important role in adaptation. However, aside from a few model species, the extent of CNV in natural populations has seldom been investigated. Here, we report on CNV in the pea aphid Acyrthosiphon pisum, a powerful system for studying the genetic architecture of host-plant adaptation and speciation thanks to multiple host races forming a continuum of genetic divergence. Recent studies have highlighted the potential importance of chemosensory genes, including the gustatory and olfactory receptor gene families (Gr and Or, respectively), in the process of host race formation. We used targeted resequencing to achieve a very high depth of coverage, and thereby revealed the extent of CNV of 434 genes, including 150 chemosensory genes, in 104 individuals distributed across eight host races of the pea aphid. We found that CNV was widespread in our global sample, with a significantly higher occurrence in multigene families, especially in Ors. We also observed a decrease in the gene probability of being completely duplicated or deleted (CDD) with increase in coding sequence length. Genes with CDD variants were usually more polymorphic for copy number, especially in the P450 gene family where toxin resistance may be related to gene dosage. We found that Gr were overrepresented among genes discriminating host races, as were CDD genes and pseudogenes. Our observations shed new light on CNV dynamics and are consistent with CNV playing a role in both local adaptation and speciation.

Differential gene expression according to race and host plant in the pea aphid.

Host-race formation in phytophagous insects is thought to provide the opportunity for local adaptation and subsequent ecological speciation. Studying gene expression differences amongst host races may help to identify phenotypes under (or resulting from) divergent selection and their genetic, molecular and physiological bases. The pea aphid (Acyrthosiphon pisum) comprises host races specializing on numerous plants in the Fabaceae and provides a unique system for examining the early stages of diversification along a gradient of genetic and associated adaptive divergence. In this study, we examine transcriptome-wide gene expression both in response to environment and across pea aphid races selected to cover the range of genetic divergence reported in this species complex. We identify changes in expression in response to host plant, indicating the importance of gene expression in aphid-plant interactions. Races can be distinguished on the basis of gene expression, and higher numbers of differentially expressed genes are apparent between more divergent races; these expression differences between host races may result from genetic drift and reproductive isolation and possibly divergent selection. Expression differences related to plant adaptation include a subset of chemosensory and salivary genes. Genes showing expression changes in response to host plant do not make up a large portion of between-race expression differences, providing confirmation of previous studies' findings that genes involved in expression differences between diverging populations or species are not necessarily those showing initial plasticity in the face of environmental change.

Insect life history and the evolution of bacterial mutualism.

Bacterial symbiosis has played a fundamental role in the evolution of eukaryotes. However, we still know little about how cooperative relationships with bacteria originate, and why they form in some host species but not others. Facultative symbionts that are beneficial, but not essential, provide unique insights into these processes. We use data from over a hundred aphid species to test if host life history is associated with the presence of facultative symbionts. We find that aphid species that have mutualistic associations with ants that protect them from natural enemies are less likely to carry symbionts that provide similar benefits. We also find one symbiont species occurs more frequently in unrelated aphid species that specialise on certain plant genera. In addition, aphid species that attack multiple plants often carry different symbiont complements. Our findings provide evidence of the ecological conditions that facilitate stable, mutually beneficial relationships between microbes and eukaryotic hosts.

Thrombolysis in patients with mild stroke: results from the Austrian Stroke Unit Registry.

BACKGROUND AND PURPOSE: Apart from missing the approved time window of 4.5 hours, one frequent cause for withholding recombinant tissue plasminogen activator (rt-PA) treatment in patients with ischemic stroke is presentation with mild deficit on admission. We analyzed in a large cohort of patients whether rt-PA treatment is beneficial for this group of patients. METHODS: From a total of 54 917 patients with ischemic stroke prospectively enrolled in the Austrian Stroke Unit Registry, 890 patients with mild deficit defined as ≤5 points in the National Institutes of Health Stroke Scale treated with and without rt-PA were matched for age, sex, prestroke disability, stroke severity, hypertension, diabetes mellitus, hypercholesterolemia, stroke cause, and clinical stroke syndrome. Functional outcome was assessed using the modified Rankin Scale at 3 months. For data visualization, weighted averages of outcome differences were computed for all age severity combinations and mapped to a color. For quantification of effect sizes, numbers need to treat were calculated. RESULTS: rt-PA-treated patients with mild deficit had a better outcome after 3 months compared with matched cases without rt-PA treatment (odds ratio [OR], 1.49; 95% confidence interval [CI], 1.17-1.89; P<0.001). In rt-PA-treated patients with mild deficit, the numbers need to treat ranged from 8 to 14. Improvement achieved by rt-PA treatment was observed along the entire age range. CONCLUSIONS: In our study, intravenous rt-PA treatment was beneficial for patients with mild deficit. Given the observational nature of these results, our data might serve as an incentive for future randomized controlled trials to provide a basis for optimal patient selection.

Sex-related differences of acute stroke unit care: results from the Austrian stroke unit registry.

BACKGROUND AND PURPOSE: Sex-related differences in quality of acute stroke care are an important concern with limited data available, specifically regarding stroke unit (SU) setting. We used the prospective nationwide Austrian SU registry to address this issue. METHODS: Our analysis covered an 8-year time period (January 2005 to December 2012) during which all patients with transient ischemic attack or ischemic stroke admitted to 1 of 35 Austrian SU had been captured in the registry. These data were analyzed for age-adjusted preclinical and clinical characteristics and quality of acute stroke care in men and women. In addition, we assessed the outcome at 3 months in multivariate analysis. RESULTS: A total of 47 209 individuals (47% women) had received SU care. Women were significantly older (median age: 77.9 versus 70.3 years), had higher pre-existing disability and more severe strokes. Correcting for age, no significant sex-related differences in quality of care were identified with comparable onset-to-door times, times to and rates of neuroimaging, as well as door-to-needle times and rates of intravenous thrombolysis (14.5% for both sexes). Despite equal acute stroke care and a comparable rate of neurorehabilitation, women had a worse functional outcome at 3-month follow-up (modified Rankin scale 3-5: odds ratio, 1.26; 95% confidence interval [1.17-1.36]), but a lower mortality (odds ratio, 0.70; 95% confidence interval [0.78-0.88]) after correcting for confounders. CONCLUSIONS: We identified no disproportions in quality of care in the acute SU setting between men and women, but the outcome was significantly different. Further studies on the poststroke period including socioeconomic aspects are needed to clarify this finding.

Myocardial infarction as a complication in acute stroke: results from the austrian stroke unit registry.

BACKGROUND: Patients with transient ischemic attack (TIA) and stroke have an increased risk for subsequent cardiac events including myocardial infarction (MI), which might be associated with a worse clinical outcome. Rapid identification of stroke patients at higher risk for MI might foster intensified cardiac monitoring or certain therapeutic strategies. However, information regarding acute MI as a complication of stroke in the very acute phase is limited. Moreover, there are no systematic data on the occurrence of MI following intracerebral hematoma. We thus aimed to assess the frequency, clinical characteristics and short-term outcome of patients suffering from acute MI in the stroke unit setting. METHODS: We analyzed 46,603 patients from 32 Austrian stroke units enrolled in the prospective Austrian Stroke Unit Registry because of TIA/acute stroke over a 6-year period (January 1, 2007 to January 13, 2013). A total of 41,619 patients (89.3%) had been treated for TIA/ischemic stroke and 4,984 (10.7%) for primary intracerebral hemorrhage (ICH). Acute MI was defined according to clinical evaluation, ECG findings and laboratory assessments. Patients with evidence for MI preceding the cerebrovascular event were not considered. RESULTS: Overall, 421 patients (1%) with TIA/ischemic stroke and 17 patients (0.3%) with ICH suffered from MI during stroke unit treatment for a median duration of 3 days. Patients with TIA/ischemic stroke and MI were significantly older, clinically more severely affected and had more frequently vascular risk factors, atrial fibrillation and previous MI. Total anterior circulation and left hemispheric stroke syndromes were more often observed in MI patients. Patients with MI not only suffered from worse short-term outcome including a higher mortality (14.5 vs. 2%; p < 0.001) at stroke unit discharge, but also acquired more stroke complications like progressive stroke and pneumonia. Multivariate analyses identified previous MI and stroke severity at admission (according to the National Institutes of Health and Stroke Scale score) as factors independently associated with the occurrence of MI on the stroke unit. CONCLUSIONS: While quite rare in the acute phase after stroke, MI is associated with a poor short-term outcome including a higher mortality. Patients with previous MI and severe stroke syndromes appear to be at particular risk for MI as an early complication in the stroke unit setting. Further studies are needed to determine whether increased vigilance and prolonged (cardiac) monitoring or certain therapeutic approaches could improve the outcome in these high-risk patients.

Minor strokes: Addressing the challenges of recanalization therapies and secondary prevention.

Minor strokes, which account for about 50 % of all ischemic strokes are not necessarily benign and carry a substantial risk of long-term disability. Due to persisting uncertainties regarding optimal recanalization strategies mild strokes may represent a therapeutical challenge for clinicians. The aim of this review is to provide an overview of the current state of knowledge and questions remaining to be answered.