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BACKGROUND AND PURPOSE: Acute ischemic stroke due to basilar artery occlusion (BAO) causes the most severe strokes and has a poor prognosis. Data regarding efficacy of endovascular thrombectomy in BAO are sparse. Therefore, in this study, we performed an analysis of the therapy of patients with BAO in routine clinical practice. METHODS: Patients enrolled between June 2015 and December 2019 in the German Stroke Registry-Endovascular Treatment (GSR-ET) were analyzed. Primary outcomes were successful reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] score of 2b-3), substantial neurological improvement (≥8-point National Institute of Health Stroke Scale [NIHSS] score reduction from admission to discharge or NIHSS score at discharge ≤1), and good functional outcome at 3 months (modified Rankin Scale [mRS] score of 0-2). RESULTS: Out of 6635 GSR-ET patients, 640 (9.6%) patients (age 72.2 ± 13.3, 43.3% female) experienced BAO (median [interquartile range] NIHSS score 17 [8, 27]). Successful reperfusion was achieved in 88.4%. Substantial neurological improvement at discharge was reached by 45.5%. At 3-month follow-up, good clinical outcome was observed in 31.1% of patients and the mortality rate was 39.2%. Analysis of mTICI3 versus mTICI2b groups showed considerable better outcome in those with mTICI3 (38.9% vs. 24.4%; p = 0.005). The strongest predictors of good functional outcome were intravenous thrombolysis (IVT) treatment (odds ratio [OR] 3.04, 95% confidence interval [CI] 1.76-5.23) and successful reperfusion (OR 4.92, 95% CI 1.15-21.11), while the effect of time between symptom onset and reperfusion seemed to be small. CONCLUSIONS: Acute reperfusion strategies in BAO are common in daily practice and can achieve good rates of successful reperfusion, neurological improvement and good functional outcome. Our data suggest that, in addition to IVT treatment, successful and, in particular, complete reperfusion (mTICI3) strongly predicts good outcome, while time from symptom onset seemed to have a lower impact.
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Arteriopatías Oclusivas , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Femenino , Masculino , Arteria Basilar , Accidente Cerebrovascular Isquémico/cirugía , Accidente Cerebrovascular Isquémico/etiología , Resultado del Tratamiento , Estudios Retrospectivos , Accidente Cerebrovascular/cirugía , Accidente Cerebrovascular/diagnóstico , Trombectomía , Arteriopatías Oclusivas/cirugía , Arteriopatías Oclusivas/etiología , Sistema de Registros , Procedimientos Endovasculares/efectos adversosRESUMEN
BACKGROUND AND PURPOSE: Reperfusion treatment in patients presenting with large vessel occlusion (LVO) and minor neurological deficits is still a matter of debate. We aimed to compare minor stroke patients treated with endovascular thrombectomy (EVT) and intravenous thrombolysis (IVT) or IVT alone. METHODS: Patients enrolled in the German Stroke Registry-Endovascular Treatment (GSR-ET) and the Safe Implementation of Treatments in Stroke-International Stroke Thrombolysis Registry (SITS-ISTR) between June 2015 and December 2019 were analyzed. Minor stroke was defined as National Institutes of Health Stroke Scale (NIHSS) score ≤5, and LVO as occlusion of the internal carotid, carotid-T, middle cerebral, basilar, vertebral or posterior cerebral arteries. GSR-ET and SITS-ISTR IVT-treated patients were matched in a 1:1 ratio using propensity-score (PS) matching. The primary outcome was good functional outcome at 3 months (modified Rankin Scale score 0-2). RESULTS: A total of 272 GSR-ET patients treated with EVT and IVT (age 68.6 ± 14.0 years, 43.4% female, NIHSS score 4 [interquartile range 2-5]) were compared to 272 IVT-treated SITS-ISTR patients (age 69.4 ± 13.7, 43.4% female, NIHSS score 4 [2-5]). Good functional outcome was seen in 77.0% versus 82.9% (p = 0.119), mortality in 5.9% versus 7.9% (p = 0.413), and intracranial hemorrhage in 8.8% versus 12.5% (p = 0.308) of patients in the GSR-ET versus the SITS-ISTR IVT group, respectively. In a second PS-matched analysis, 624 GSR-ET patients (IVT rate 56.7%) and 624 SITS-ISTR patients (IVT rate 100%), good outcome was more often observed in the SITS-ISTR patients (68.2% vs. 80.9%; p < 0.001), and IVT independently predicted good outcome (odds ratio 2.16, 95% confidence interval 1.43-3.28). CONCLUSIONS: Our study suggests similar effectiveness of IVT alone compared to EVT with or without IVT in minor stroke patients. There is an urgent need for randomized controlled trials on this topic.
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Isquemia Encefálica , Accidente Cerebrovascular , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/tratamiento farmacológico , Femenino , Fibrinolíticos/uso terapéutico , Humanos , Hemorragias Intracraneales , Masculino , Persona de Mediana Edad , Sistema de Registros , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/cirugía , Trombectomía , Terapia Trombolítica , Resultado del TratamientoRESUMEN
The behavioural rhythms of organisms are thought to be under strong selection, influenced by the rhythmicity of the environment. Such behavioural rhythms are well studied in isolated individuals under laboratory conditions, but free-living individuals have to temporally synchronize their activities with those of others, including potential mates, competitors, prey and predators. Individuals can temporally segregate their daily activities (for example, prey avoiding predators, subordinates avoiding dominants) or synchronize their activities (for example, group foraging, communal defence, pairs reproducing or caring for offspring). The behavioural rhythms that emerge from such social synchronization and the underlying evolutionary and ecological drivers that shape them remain poorly understood. Here we investigate these rhythms in the context of biparental care, a particularly sensitive phase of social synchronization where pair members potentially compromise their individual rhythms. Using data from 729 nests of 91 populations of 32 biparentally incubating shorebird species, where parents synchronize to achieve continuous coverage of developing eggs, we report remarkable within- and between-species diversity in incubation rhythms. Between species, the median length of one parent's incubation bout varied from 1-19 h, whereas period length-the time in which a parent's probability to incubate cycles once between its highest and lowest value-varied from 6-43 h. The length of incubation bouts was unrelated to variables reflecting energetic demands, but species relying on crypsis (the ability to avoid detection by other animals) had longer incubation bouts than those that are readily visible or who actively protect their nest against predators. Rhythms entrainable to the 24-h light-dark cycle were less prevalent at high latitudes and absent in 18 species. Our results indicate that even under similar environmental conditions and despite 24-h environmental cues, social synchronization can generate far more diverse behavioural rhythms than expected from studies of individuals in captivity. The risk of predation, not the risk of starvation, may be a key factor underlying the diversity in these rhythms.
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Charadriiformes/fisiología , Comportamiento de Nidificación/fisiología , Periodicidad , Conducta Predatoria , Animales , Evolución Biológica , Charadriiformes/clasificación , Ritmo Circadiano , Señales (Psicología) , Ambiente , Conducta Alimentaria , Femenino , Masculino , Fotoperiodo , Reproducción , Especificidad de la Especie , Inanición/veterinaria , Factores de Tiempo , Cigoto/crecimiento & desarrolloRESUMEN
[Figure: see text].
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Enfermedades de las Arterias Carótidas/patología , Enfermedades de las Arterias Carótidas/cirugía , Procedimientos Endovasculares/métodos , Accidente Cerebrovascular/patología , Accidente Cerebrovascular/cirugía , Anciano , Trastornos Cerebrovasculares/patología , Trastornos Cerebrovasculares/cirugía , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Trombectomía/métodosRESUMEN
BACKGROUND AND PURPOSE: Up to 30% of infective endocarditis (IE) patients have ischemic stroke as a complication. Standard treatment with mechanical thrombectomy (MT) with or without intravenous thrombolysis for large vessel occlusion (LVO) has not been evaluated formally in these patients. METHODS: Patients enrolled in the German Stroke Registry-Endovascular Treatment (GSR-ET) between June 2015 and December 2019 were analyzed. Patients with stroke due to IE and patients with cardioembolic stroke and atrial fibrillation (AF) were compared using propensity score matching. Successful reperfusion was defined as modified Thrombolysis in Cerebral Infarction score = 2b-3. Modified Rankin Scale (mRS) = 0-2 at 3 months indicated good outcome. RESULTS: Of 6635 patients, 55 patients (age = 69.0 ± 13.3 years, 43.6% female, median premorbid mRS (pmRS) = 1, interquartile range [IQR] = 0-1, National Institutes of Health Stroke Scale [NIHSS] = 15, IQR = 10-21) presented with septic embolic stroke due to IE and were compared to 104 patients (age = 66.5 ± 13.4 years, 39.4% female, pmRS = 0, IQR = 0-2, NIHSS = 16, IQR = 10-20) with cardioembolic stroke due to AF. Successful recanalization was achieved in 74.5% of endocarditis patients compared to 87.5% of controls (p = 0.039). Intracranial hemorrhage rates were comparable (30.9% vs. 21.6%, p = 0.175). Good functional outcome was 20.0% in patients with IE compared to 43.3% in matched patients (p = 0.006), with a significantly higher mortality (60.0% vs. 28.8%, p < 0.001). IE was strongly associated with poor outcome (odds ratio [OR] = 0.32, 95% confidence interval [CI] = 0.11-0.87, p = 0.03 for good outcome) and mortality (OR = 4.49, 95% CI = 1.80-10.68, p = 0.001). CONCLUSIONS: Although MT results in high successful recanalization rates with acceptable safety profile, patients with LVO stroke due to IE have poor outcome.
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Isquemia Encefálica , Endocarditis , Procedimientos Endovasculares , Accidente Cerebrovascular , Isquemia Encefálica/complicaciones , Isquemia Encefálica/cirugía , Endocarditis/complicaciones , Endocarditis/cirugía , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Sistema de Registros , Estudios Retrospectivos , Accidente Cerebrovascular/cirugía , Trombectomía , Resultado del TratamientoRESUMEN
BACKGROUND: Understanding the structure and variability of adaptive loci such as the major histocompatibility complex (MHC) genes is a primary research goal for evolutionary and conservation genetics. Typically, classical MHC genes show high polymorphism and are under strong balancing selection, as their products trigger the adaptive immune response in vertebrates. Here, we assess the allelic diversity and patterns of selection for MHC class I and class II loci in a threatened shorebird with highly flexible mating and parental care behaviour, the Snowy Plover (Charadrius nivosus) across its broad geographic range. RESULTS: We determined the allelic and nucleotide diversity for MHC class I and class II genes using samples of 250 individuals from eight breeding population of Snowy Plovers. We found 40 alleles at MHC class I and six alleles at MHC class II, with individuals carrying two to seven different alleles (mean 3.70) at MHC class I and up to two alleles (mean 1.45) at MHC class II. Diversity was higher in the peptide-binding region, which suggests balancing selection. The MHC class I locus showed stronger signatures of both positive and negative selection than the MHC class II locus. Most alleles were present in more than one population. If present, private alleles generally occurred at very low frequencies in each population, except for the private alleles of MHC class I in one island population (Puerto Rico, lineage tenuirostris). CONCLUSION: Snowy Plovers exhibited an intermediate level of diversity at the MHC, similar to that reported in other Charadriiformes. The differences found in the patterns of selection between the class I and II loci are consistent with the hypothesis that different mechanisms shape the sequence evolution of MHC class I and class II genes. The rarity of private alleles across populations is consistent with high natal and breeding dispersal and the low genetic structure previously observed at neutral genetic markers in this species.
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Charadriiformes , Genética de Población , Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase I/genética , Selección Genética , Alelos , Animales , Charadriiformes/genética , Especies en Peligro de Extinción , Variación Genética , FilogeniaRESUMEN
Background and Purpose- Stroke etiology drives thrombus composition. We thus hypothesized that endovascular treatment shows different efficacy in cardioembolic versus noncardioembolic large-vessel occlusions (LVOs). Methods- Procedural characteristics, grade of reperfusion, and functional outcome at discharge and 90 days were compared between patients with cardioembolic versus noncardioembolic LVO from the GSR-ET (German Stroke Registry-Endovascular Treatment; n=2589). To determine associations with functional outcome, adjusted odds ratios and 95% CIs were calculated using ordinal multivariable logistic regression models adjusting for potential baseline confounder variables. Results- Endovascular treatment of cardioembolic LVO had a higher rate of successful reperfusion (85.6% versus 81.0%; P=0.002) and a higher rate of complete reperfusion after a single thrombectomy pass (45.7% versus 38.1%; P<0.001) compared with noncardioembolic LVO. Cardioembolic LVO was associated with better functional outcome at discharge (adjusted odds ratio, 1.61 [95% CI, 1.37-1.88]) and 90 days (adjusted odds ratio, 1.29 [95% CI, 1.09-1.53]). In mediation analysis, reperfusion explained 47% of the effect of etiology on functional outcome at discharge. Conclusions- These results provide evidence for higher efficacy of endovascular treatment in cardioembolic LVO compared with noncardioembolic LVO.
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Procedimientos Endovasculares , Embolia Intracraneal/cirugía , Sistema de Registros , Accidente Cerebrovascular/cirugía , Trombectomía , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Embolia Intracraneal/epidemiología , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/epidemiologíaRESUMEN
Nuclear clearance of TDP-43 into cytoplasmic aggregates is a key driver of neurodegeneration in amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD), but the mechanisms are unclear. Here, we show that TDP-43 knockdown specifically reduces the number and motility of RAB11-positive recycling endosomes in dendrites, while TDP-43 overexpression has the opposite effect. This is associated with delayed transferrin recycling in TDP-43-knockdown neurons and decreased ß2-transferrin levels in patient CSF Whole proteome quantification identified the upregulation of the ESCRT component VPS4B upon TDP-43 knockdown in neurons. Luciferase reporter assays and chromatin immunoprecipitation suggest that TDP-43 represses VPS4B transcription. Preventing VPS4B upregulation or expression of its functional antagonist ALIX restores trafficking of recycling endosomes. Proteomic analysis revealed the broad reduction in surface expression of key receptors upon TDP-43 knockdown, including ErbB4, the neuregulin 1 receptor. TDP-43 knockdown delays the surface delivery of ErbB4. ErbB4 overexpression, but not neuregulin 1 stimulation, prevents dendrite loss upon TDP-43 knockdown. Thus, impaired recycling of ErbB4 and other receptors to the cell surface may contribute to TDP-43-induced neurodegeneration by blocking trophic signaling.
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Proteínas de Unión al ADN/metabolismo , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Endosomas/metabolismo , Neuronas/metabolismo , Receptor ErbB-4/metabolismo , ATPasas Asociadas con Actividades Celulares Diversas , Adenosina Trifosfatasas/genética , Adenosina Trifosfatasas/metabolismo , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Células Cultivadas , Proteínas de Unión al ADN/genética , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Degeneración Lobar Frontotemporal/genética , Degeneración Lobar Frontotemporal/metabolismo , Técnicas de Silenciamiento del Gen , Hipocampo/citología , Humanos , Transporte de Proteínas , Ratas , Receptor ErbB-4/genética , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos/metabolismo , Transducción de SeñalRESUMEN
Adult sex ratio (ASR) is a central concept in population biology and a key factor in sexual selection, but why do most demographic models ignore sex biases? Vital rates often vary between the sexes and across life history, but their relative contributions to ASR variation remain poorly understood-an essential step to evaluate sex ratio theories in the wild and inform conservation. Here, we combine structured two-sex population models with individual-based mark-recapture data from an intensively monitored polygamous population of snowy plovers. We show that a strongly male-biased ASR (0.63) is primarily driven by sex-specific survival of juveniles rather than adults or dependent offspring. This finding provides empirical support for theories of unbiased sex allocation when sex differences in survival arise after the period of parental investment. Importantly, a conventional model ignoring sex biases significantly overestimated population viability. We suggest that sex-specific population models are essential to understand the population dynamics of sexual organisms: reproduction and population growth are most sensitive to perturbations in survival of the limiting sex. Overall, our study suggests that sex-biased early survival may contribute toward mating system evolution and population persistence, with implications for both sexual selection theory and biodiversity conservation.
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Charadriiformes/fisiología , Reproducción , Razón de Masculinidad , Conducta Sexual Animal , Algoritmos , Animales , Biodiversidad , Charadriiformes/genética , Femenino , Humanos , Masculino , México , Modelos Estadísticos , Dinámica Poblacional , Crecimiento Demográfico , Caracteres Sexuales , Factores SexualesRESUMEN
Molecular diagnosis of mitochondrial disorders is challenging because of extreme clinical and genetic heterogeneity. By exome sequencing, we identified three different bi-allelic truncating mutations in TANGO2 in three unrelated individuals with infancy-onset episodic metabolic crises characterized by encephalopathy, hypoglycemia, rhabdomyolysis, arrhythmias, and laboratory findings suggestive of a defect in mitochondrial fatty acid oxidation. Over the course of the disease, all individuals developed global brain atrophy with cognitive impairment and pyramidal signs. TANGO2 (transport and Golgi organization 2) encodes a protein with a putative function in redistribution of Golgi membranes into the endoplasmic reticulum in Drosophila and a mitochondrial localization has been confirmed in mice. Investigation of palmitate-dependent respiration in mutant fibroblasts showed evidence of a functional defect in mitochondrial ß-oxidation. Our results establish TANGO2 deficiency as a clinically recognizable cause of pediatric disease with multi-organ involvement.
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Alelos , Arritmias Cardíacas/genética , Cardiomiopatías/genética , Mutación , Arritmias Cardíacas/diagnóstico , Cardiomiopatías/diagnóstico , Preescolar , Exoma , Femenino , Humanos , Lactante , Masculino , Mitocondrias/genética , Mitocondrias/metabolismo , Enfermedades Mitocondriales/diagnóstico , Enfermedades Mitocondriales/genética , LinajeRESUMEN
BACKGROUND: Marine and intertidal organisms face the rhythmic environmental changes induced by tides. The large amplitude of spring tides that occur around full and new moon may threaten nests of ground-nesting birds. These birds face a trade-off between ensuring nest safety from tidal flooding and nesting near the waterline to provide their newly hatched offspring with suitable foraging opportunities. The semi-lunar periodicity of spring tides may enable birds to schedule nest initiation adaptively, for example, by initiating nests around tidal peaks when the water line reaches the farthest into the intertidal habitat. We examined the impact of semi-lunar tidal changes on the phenology of nest flooding and nest initiation in Snowy Plovers (Charadrius nivosus) breeding at Bahía de Ceuta, a coastal wetland in Northwest Mexico. RESULTS: Using nest initiations and fates of 752 nests monitored over ten years we found that the laying season coincides with the lowest spring tides of the year and only 6% of all nests were flooded by tides. Tidal nest flooding varied substantially over time. First, flooding was the primary cause of nest failures in two of the ten seasons indicating high between-season stochasticity. Second, nests were flooded almost exclusively during the second half of the laying season. Third, nest flooding was associated with the semi-lunar spring tide cycle as nests initiated around spring tide had a lower risk of being flooded than nests initiated at other times. Following the spring tide rhythm, plovers appeared to adapt to this risk of flooding with nest initiation rates highest around spring tides and lowest around neap tides. CONCLUSIONS: Snowy Plovers appear generally well adapted to the risk of nest flooding by spring tides. Our results are in line with other studies showing that intertidal organisms have evolved adaptive responses to predictable rhythmic tidal changes but these adaptations do not prevent occasional catastrophic losses caused by stochastic events.
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Background and Purpose- We aimed to describe the safety and efficacy of immediate mechanical thrombectomy (MT) in patients with large vessel occlusions and low National Institutes of Health Stroke Scale (NIHSS) versus best medical management. Methods- Patients from prospectively collected databases of 6 international comprehensive stroke centers with large vessel occlusions (distal intracranial internal carotid, middle cerebral artery-M1 and M2 segments, or basilar artery with or without tandem occlusions) and NIHSS 0 to 5 were identified and divided into 2 groups for analysis: immediate MT or initial best medical management which included rescue MT after neurological deterioration (best medical management-MT). Uni- and multivariate analyses and patient-level matching for age, baseline NIHSS, and occlusion site were performed to compare baseline and outcome variables across the 2 groups. The primary outcome was defined as good outcome (modified Rankin Scale score, 0-2) at day 90. Safety outcome was symptomatic intracranial hemorrhage as defined by the ECASS (European Cooperative Acute Stroke Study) II and mortality at day 90. Results- Compared with best medical management-MT (n=220), patients with immediate MT (n=80) were younger (65.3±13.5 versus 69.5±14.1; P=0.021), had more often atrial fibrillation (44.8% versus 28.2%; P=0.012), higher baseline NIHSS (4, 0-5 versus 3, 0-5; P=0.005), higher Alberta Stroke Program Early CT Score (10, 7-10 versus 10, 5-10; P=0.023), more middle cerebral artery-M1, and less middle cerebral artery-M2 (41.3% versus 21.9% and 28.8% versus 49.3%; P=0.016) occlusions. The adjusted odds ratio for good outcome was 3.1 (95% CI, 1.4-6.9) favoring immediate MT. In the matched analysis, there was a 14.4% absolute difference in good outcome (84.4% versus 70.1%; P=0.03) at day 90 favoring immediate MT. There were no safety concerns. Conclusions- Our retrospective, pilot analysis suggests that immediate thrombectomy in large vessel occlusions patients with low NIHSS on presentation may be safe and has the potential to result in improved outcomes. Randomized clinical trials are warranted to establish the optimal management for this patient population.
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Isquemia Encefálica/terapia , Hemorragias Intracraneales/terapia , Accidente Cerebrovascular/terapia , Trombectomía , Anciano , Anciano de 80 o más Años , Arteria Carótida Interna/cirugía , Procedimientos Endovasculares/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trombectomía/efectos adversos , Activador de Tejido Plasminógeno/uso terapéutico , Resultado del TratamientoRESUMEN
Since 2011, new oral anticoagulants (NOAC) can be prescribed for prevention of cardio-embolic ischemic strokes in addition to vitamin K antagonists. NOAC are indicated in patients with non-valvular atrial fibrillation. Although its use is a matter of debate in Germany, the neurological and cardiological societies recommend the use of NOAC over and above vitamin K antagonists due to a better benefit-to-risk ratio attributed to it, especially because of the lower risk of intracranial hemorrhage in NOAC use. A specific antidote is commercially available for the direct thrombin inhibitor dabigatran only. For the factor Xa inhibitors, an antidote is being investigated in clinical trials. To our best knowledge, there are no direct head-to-head studies between the NOACs. Therefore, none of them can be assumed to be superior and the decision for a specific NOAC should be based on the available scientific data from the NOAC trials considering the individual patient's characteristics and comorbidities.
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Anticoagulantes/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Anticoagulantes/efectos adversos , Antídotos/uso terapéutico , Fibrinolíticos/uso terapéutico , Humanos , Vitamina K/antagonistas & inhibidoresRESUMEN
Ornamentation of parents poses a high risk for offspring because it reduces cryptic nest defence. Over a century ago, Wallace proposed that sexual dichromatism enhances crypsis of open-nesting females although subsequent studies found that dichromatism per se is not necessarily adaptive. We tested whether reduced female ornamentation in a sexually dichromatic species reduces the risk of clutch depredation and leads to adaptive parental roles in the red-capped plover Charadrius ruficapillus, a species with biparental incubation. Males had significantly brighter and redder head coloration than females. During daytime, when visually foraging predators are active, colour-matched model males incurred a higher risk of clutch depredation than females, whereas at night there was no difference in depredation risk between sexes. In turn, red-capped plovers maintained a strongly diurnal/nocturnal division of parental care during incubation, with males attending the nest largely at night when visual predators were inactive and females incubating during the day. We found support for Wallace's conclusion that reduced female ornamentation provides a selective advantage when reproductive success is threatened by visually foraging predators. We conclude that predators may alter their prey's parental care patterns and therefore may affect parental cooperation during care.
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Charadriiformes/fisiología , Comportamiento de Nidificación , Animales , Ritmo Circadiano , Femenino , Masculino , Pigmentación , Caracteres Sexuales , VictoriaRESUMEN
Establishing phylogenetic relationships within a clade can help to infer ancestral origins and indicate how widespread species reached their current biogeographic distributions. The small plovers, genus Charadrius, are cosmopolitan shorebirds, distributed across all continents except Antarctica. Here we present a global, species-level molecular phylogeny of this group based on four nuclear (ADH5, FIB7, MYO2 and RAG1) and two mitochondrial (COI and ND3) genes, and use the phylogeny to examine the biogeographic origin of the genus. A Bayesian multispecies coalescent approach identified two major clades (CRD I and CRD II) within the genus. Clade CRD I contains three species (Thinornis novaeseelandiae, Thinornis rubricollis and Eudromias morinellus), and CRD II one species (Anarhynchus frontalis), that were previously placed outside the Charadrius genus. In contrast to earlier work, ancestral area analyses using parsimony and Bayesian methods supported an origin of the Charadrius plovers in the Northern hemisphere. We propose that major radiations in this group were associated with shifts in the range of these ancestral plover species, leading to colonisation of the Southern hemisphere.
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Charadriiformes/clasificación , Charadriiformes/genética , Filogenia , Animales , Teorema de Bayes , Marcadores Genéticos/genética , Filogeografía , Reproducibilidad de los ResultadosRESUMEN
A massive expansion of a GGGGCC repeat upstream of the C9orf72 coding region is the most common known cause of amyotrophic lateral sclerosis and frontotemporal dementia. Despite its intronic localization and lack of a canonical start codon, both strands are translated into aggregating dipeptide repeat (DPR) proteins: poly-GA, poly-GP, poly-GR, poly-PR and poly-PA. To address conflicting findings on the predominant toxicity of the different DPR species in model systems, we compared the expression pattern of the DPR proteins in rat primary neurons and postmortem brain and spinal cord of C9orf72 mutation patients. Only poly-GA overexpression closely mimicked the p62-positive neuronal cytoplasmic inclusions commonly observed for all DPR proteins in patients. In contrast, overexpressed poly-GR and poly-PR formed nucleolar p62-negative inclusions. In patients, most of the less common neuronal intranuclear DPR inclusions were para-nucleolar and p62 positive. Neuronal nucleoli in C9orf72 cases showed normal size and morphology regardless of the presence of poly-GR and poly-PR inclusions arguing against widespread nucleolar stress, reported in cellular models. Colocalization of para-nucleolar DPR inclusions with heterochromatin and a marker of transcriptional repression (H3K9me2) indicates a link to gene transcription. In contrast, we detected numerous intranuclear DPR inclusions not associated with nucleolar structures in ependymal and subependymal cells. In patients, neuronal inclusions of poly-GR, poly-GP and the poly-GA interacting protein Unc119 were less abundant than poly-GA inclusions, but showed similar regional and subcellular distribution. Regardless of neurodegeneration, all inclusions were most abundant in neocortex, hippocampus and thalamus, with few inclusions in brain stem and spinal cord. In the granular cell layer of the cerebellum, poly-GA and Unc119 inclusions were significantly more abundant in cases with FTLD than in cases with MND and FTLD/MND. Poly-PR inclusions were rare throughout the brain but significantly more abundant in the CA3/4 region of FTLD cases than in MND cases. Thus, although DPR distribution is not correlated with neurodegeneration spatially, it correlates with neuropathological subtypes.
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Expansión de las Repeticiones de ADN , Silenciador del Gen , Proteínas/genética , Proteínas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adulto , Anciano , Animales , Encéfalo/metabolismo , Encéfalo/patología , Proteína C9orf72 , Nucléolo Celular/metabolismo , Nucléolo Celular/patología , Estudios de Cohortes , Degeneración Lobar Frontotemporal/complicaciones , Degeneración Lobar Frontotemporal/genética , Degeneración Lobar Frontotemporal/metabolismo , Degeneración Lobar Frontotemporal/patología , Humanos , Cuerpos de Inclusión/metabolismo , Cuerpos de Inclusión/patología , Persona de Mediana Edad , Enfermedad de la Neurona Motora/complicaciones , Enfermedad de la Neurona Motora/genética , Enfermedad de la Neurona Motora/metabolismo , Enfermedad de la Neurona Motora/patología , Neuroglía/metabolismo , Neuroglía/patología , Neuronas/metabolismo , Neuronas/patología , Ratas , Médula Espinal/metabolismo , Médula Espinal/patologíaRESUMEN
As a result of an error during digital processing of Figure 1a for publication, one of the immunofluorescence panels (GA175-GFP Nucleolin staining) was accidentally strongly altered in contrast and brightness. The corrected version of the figure is shown below. The authors apologize for any confusion caused by this error. In the published article, the collaborators from the two institutions, German Consortium for Frontotemporal Lobar Degeneration and Bavarian Brain Banking Alliance, were incorrectly listed in article note. These names have been relocated to the Appendix section in the article now.Figure 1a and the collaborators list have been amended in the published article.
RESUMEN
Sequence variation in the melanocortin-1 receptor (MC1R) gene explains color morph variation in several species of birds and mammals. Ruffs (Philomachus pugnax) exhibit major dark/light color differences in melanin-based male breeding plumage which is closely associated with alternative reproductive behavior. A previous study identified a microsatellite marker (Ppu020) near the MC1R locus associated with the presence/absence of ornamental plumage. We investigated whether coding sequence variation in the MC1R gene explains major dark/light plumage color variation and/or the presence/absence of ornamental plumage in ruffs. Among 821bp of the MC1R coding region from 44 male ruffs we found 3 single nucleotide polymorphisms, representing 1 nonsynonymous and 2 synonymous amino acid substitutions. None were associated with major dark/light color differences or the presence/absence of ornamental plumage. At all amino acid sites known to be functionally important in other avian species with dark/light plumage color variation, ruffs were either monomorphic or the shared polymorphism did not coincide with color morph. Neither ornamental plumage color differences nor the presence/absence of ornamental plumage in ruffs are likely to be caused entirely by amino acid variation within the coding regions of the MC1R locus. Regulatory elements and structural variation at other loci may be involved in melanin expression and contribute to the extreme plumage polymorphism observed in this species.
Asunto(s)
Aves/genética , Plumas , Variación Genética , Pigmentación/genética , Receptor de Melanocortina Tipo 1/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Genotipo , Masculino , Melaninas , Datos de Secuencia Molecular , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADNRESUMEN
Whether endovascular thrombectomy (EVT) improves functional outcome in patients with large-vessel occlusion (LVO) stroke that do not comply with inclusion criteria of randomized controlled trials (RCTs) but that are considered for EVT in clinical practice is uncertain. We aimed to systematically identify patients with LVO stroke underrepresented in RCTs who might benefit from EVT. Following the premises that (i) patients without reperfusion after EVT represent a non-treated control group and (ii) the level of reperfusion affects outcome in patients with benefit from EVT but not in patients without treatment benefit, we systematically assessed the importance of reperfusion level on functional outcome prediction using machine learning in patients with LVO stroke treated with EVT in clinical practice (N = 5235, German-Stroke-Registry) and in patients treated with EVT or best medical management from RCTs (N = 1488, Virtual-International-Stroke-Trials-Archive). The importance of reperfusion level on outcome prediction in an RCT-like real-world cohort equaled the importance of EVT treatment allocation for outcome prediction in RCT data and was higher compared to an unselected real-world population. The importance of reperfusion level was magnified in patient groups underrepresented in RCTs, including patients with lower NIHSS scores (0-10), M2 occlusions, and lower ASPECTS (0-5 and 6-8). Reperfusion level was equally important in patients with vertebrobasilar as with anterior LVO stroke. The importance of reperfusion level for outcome prediction identifies patient target groups who likely benefit from EVT, including vertebrobasilar stroke patients and among patients underrepresented in RCT patients with low NIHSS scores, low ASPECTS, and M2 occlusions.