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2.
Oecologia ; 192(2): 501-514, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31872269

RESUMO

Vertical niche partitioning might be one of the main driving forces explaining the high diversity of forest ecosystems. However, the forest's vertical dimension has received limited investigation, especially in temperate forests. Thus, our knowledge about how communities are vertically structured remains limited for temperate forest ecosystems. In this study, we investigated the vertical structuring of an arboreal caterpillar community in a temperate deciduous forest of eastern North America. Within a 0.2-ha forest stand, all deciduous trees ≥ 5 cm diameter at breast height (DBH) were felled and systematically searched for caterpillars. Sampled caterpillars were assigned to a specific stratum (i.e. understory, midstory, or canopy) depending on their vertical position and classified into feeding guild as either exposed feeders or shelter builders (i.e. leaf rollers, leaf tiers, webbers). In total, 3892 caterpillars representing 215 species of butterflies and moths were collected and identified. While stratum had no effect on caterpillar density, feeding guild composition changed significantly with shelter-building caterpillars becoming the dominant guild in the canopy. Species richness and diversity were found to be highest in the understory and midstory and declined strongly in the canopy. Family and species composition changed significantly among the strata; understory and canopy showed the lowest similarity. Food web analyses further revealed an increasing network specialization towards the canopy, caused by an increase in specialization of the caterpillar community. In summary, our study revealed a pronounced stratification of a temperate forest caterpillar community, unveiling a distinctly different assemblage of caterpillars dwelling in the canopy stratum.


Assuntos
Biodiversidade , Ecossistema , Animais , Florestas , América do Norte , Árvores
3.
J Neuroimaging ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31749218

RESUMO

BACKGROUND AND PURPOSE: Microembolic signals (MES) are detectable by transcranial Doppler monitoring and associated with increased risk of first or recurrent ischemic stroke. MES detection can also illuminate stroke etiology and the effect of prophylactic treatment. MES detection cannot accurately distinguish between stroke-related microemboli and ultrasound contrast agents. These agents contain microbubbles and are frequently used in neuro- and cardiovascular diagnostics. We aimed to assess how long after contrast infusion microbubbles are detectable by transcranial Doppler monitoring. METHODS: Ten healthy volunteers received an intravenous infusion of stabilized sulfur hexafluoride microbubbles (SonoVue®) for 30 minutes. The infusion was followed by continuous unilateral Doppler monitoring (TCD-X, Atys Medical, Soucieu-en-Jarrest, France) for 3.5 hours. RESULTS: MES persisted for 12 to 77 minutes (median 40.5 minutes), and the frequency tended to decrease gradually until cessation. CONCLUSIONS: None of the subjects had detectable MES for more than 77 minutes after ultrasound contrast infusion. MES detection with the intent to detect stroke-related microemboli should wait for at least this long after completed infusion.

4.
Int J Parasitol ; 49(13-14): 1075-1086, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31734337

RESUMO

The extreme biological diversity of Oceanian archipelagos has long stimulated research in ecology and evolution. However, parasitic protists in this geographic area remained neglected and no molecular analyses have been carried out to understand the evolutionary patterns and relationships with their hosts. Papua New Guinea (PNG) is a biodiversity hotspot containing over 5% of the world's biodiversity in less than 0.5% of the total land area. In the current work, we examined insect heteropteran hosts collected in PNG for the presence of trypanosomatid parasites. The diversity of insect flagellates was analysed, to our knowledge for the first time, east of Wallace's Line, one of the most distinct biogeographic boundaries of the world. Out of 907 investigated specimens from 138 species and 23 families of the true bugs collected in eight localities, 135 (15%) were infected by at least one trypanosomatid species. High species diversity of captured hosts correlated with high diversity of detected trypanosomatids. Of 46 trypanosomatid Typing Units documented in PNG, only eight were known from other geographic locations, while 38 TUs (~83%) have not been previously encountered. The widespread trypanosomatid TUs were found in both widely distributed and endemic/sub-endemic insects. Approximately one-third of the endemic trypanosomatid TUs were found in widely distributed hosts, while the remaining species were confined to endemic and sub-endemic insects. The TUs from PNG form clades with conspicuous host-parasite coevolutionary patterns, as well as those with a remarkable lack of this trait. In addition, our analysis revealed new members of the subfamilies Leishmaniinae and Strigomonadinae, potentially representing new genera of trypanosomatids.

5.
PLoS One ; 14(10): e0222119, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644586

RESUMO

Research on canopy arthropods has progressed from species inventories to the study of their interactions and networks, enhancing our understanding of how hyper-diverse communities are maintained. Previous studies often focused on sampling individual tree species, individual trees or their parts. We argue that such selective sampling is not ideal when analyzing interaction network structure, and may lead to erroneous conclusions. We developed practical and reproducible sampling guidelines for the plot-based analysis of arthropod interaction networks in forest canopies. Our sampling protocol focused on insect herbivores (leaf-chewing insect larvae, miners and gallers) and non-flying invertebrate predators (spiders and ants). We quantitatively sampled the focal arthropods from felled trees, or from trees accessed by canopy cranes or cherry pickers in 53 0.1 ha forest plots in five biogeographic regions, comprising 6,280 trees in total. All three methods required a similar sampling effort and provided good foliage accessibility. Furthermore, we compared interaction networks derived from plot-based data to interaction networks derived from simulated non-plot-based data focusing either on common tree species or a representative selection of tree families. All types of non-plot-based data showed highly biased network structure towards higher connectance, higher web asymmetry, and higher nestedness temperature when compared with plot-based data. Furthermore, some types of non-plot-based data showed biased diversity of the associated herbivore species and specificity of their interactions. Plot-based sampling thus appears to be the most rigorous approach for reconstructing realistic, quantitative plant-arthropod interaction networks that are comparable across sites and regions. Studies of plant interactions have greatly benefited from a plot-based approach and we argue that studies of arthropod interactions would benefit in the same way. We conclude that plot-based studies on canopy arthropods would yield important insights into the processes of interaction network assembly and dynamics, which could be maximised via a coordinated network of plot-based study sites.

6.
Stroke ; 50(12): 3625-3627, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31537192

RESUMO

Background and Purpose- Patients with acute cerebral infarcts in multiple arterial territories (MACI) represent a substantial portion of the stroke population. There are no data on short-term outcome and in-hospital complications in patients with MACI. We compared patients with MACI with patients having acute cerebral infarct(s) in a single arterial territory. Methods- We analyzed 3343 patients with diffusion-weighted imaging-confirmed acute cerebral infarcts. MACI was defined as at least 2 acute cerebral ischemic lesions in at least 2 arterial cerebral territories. Patients with MACI were compared with patients with acute cerebral infarct(s) in a single arterial territory for relevant in-hospital complications and short-term outcome, namely National Institutes of Health Stroke Scale and modified Rankin Scale at day 7 after admission or at discharge when earlier. Results- A total of 311 patients (9.3%) met the definition of MACI. Both median National Institutes of Health Stroke Scale (2 [1-7] versus 1 [0-4]) and modified Rankin Scale (3 [1-4] versus 2 [1-3]) were higher in patients with MACI. MACI was independently associated with higher National Institutes of Health Stroke Scale and modified Rankin Scale. Deep venous thrombosis, myocardial infarction, and any complications were more frequent in patients with MACI. Conclusions- In-hospital complications were more frequent in patients with MACI, which may adversely affect short-term clinical and functional outcome. Closer follow-up of patients with MACI during hospitalization may prevent such events and negative progression.

7.
Stroke ; 50(10): 2937-2940, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31446883

RESUMO

Background and Purpose- Stroke mimics (SM) pose a common clinical challenge, but the burden of SM in patients with previous ischemic stroke (IS) or transient ischemic attack is unknown. The objective of this study was to calculate the incidence of SM in IS survivors, compare it with the incidence of recurrent stroke in the same population, and explore the time-dependent patterns of SM etiologies. Methods- This prospective cohort study registered SM events and etiologies among 1872 IS and transient ischemic attack survivors diagnosed with index stroke at Haukeland University Hospital stroke unit from 2007 to 2013 by review of medical records. Cumulative incidences of SM were estimated with a competing risks Cox model and compared with incidence of recurrent stroke in the same population. Results- During 8172 person-years of follow-up, 339 patients had 480 SM events. The cumulative incidence rate of SM during follow-up was 58.7 per 1.000 person-years (95% CI, 53.7-64.2) compared with 34.0 per 1.000 person-years (95% CI, 30.2-38.2) for recurrent stroke in the same time period. The risks of SM and recurrent stroke were highest the first year after index IS or transient ischemic attack. The most frequent SM diagnoses were sequelae of cerebral infarction (19.8%), medical observation, and evaluation for suspected cerebrovascular disease (15.6%) and infections (14.0%). The 2 most frequent and unspecific diagnoses (sequelae of cerebral infarction and medical observation) were clustered in the first months after index stroke. Conclusions- SM after IS or transient ischemic attack are more frequent than recurrent stroke and the risk is especially high in the early period. SMs are multietiological and unspecific diagnoses are most frequent early after index stroke.

8.
Mol Ecol ; 28(17): 3958-3976, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31338917

RESUMO

Even though speciation involving multiple interacting partners, such as plants and their pollinators, has attracted much research, most studies focus on isolated phases of the process. This currently precludes an integrated understanding of the mechanisms leading to cospeciation. Here, we examine population genetic structure across six species-pairs of figs and their pollinating wasps along an elevational gradient in New Guinea. Specifically, we test three hypotheses on the genetic structure within the examined species-pairs and find that the hypothesized genetic structures represent different phases of a single continuum, from incipient cospeciation to the full formation of new species. Our results also illuminate the mechanisms governing cospeciation, namely that fig wasps tend to accumulate population genetic differences faster than their figs, which initially decouples the speciation dynamics between the two interacting partners and breaks down their one-to-one matching. This intermediate phase is followed by genetic divergence of both partners, which may eventually restore the one-to-one matching among the fully formed species. Together, these findings integrate current knowledge on the mechanisms operating during different phases of the cospeciation process. They also reveal that the increasingly reported breakdowns in one-to-one matching may be an inherent part of the cospeciation process. Mechanistic understanding of this process is needed to explain how the extraordinary diversity of species, especially in the tropics, has emerged. Knowing which breakdowns in species interactions are a natural phase of cospeciation and which may endanger further generation of diversity seems critical in a constantly changing world.

9.
Eur Stroke J ; 4(2): 172-180, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31259265

RESUMO

Purpose: Paroxysmal atrial fibrillation is often suspected as a probable cause of cryptogenic stroke. Continuous long-term ECG monitoring using insertable cardiac monitors is a clinically effective technique to screen for atrial fibrillation and superior to conventional follow-up in cryptogenic stroke. However, more studies are needed to identify factors which can help selecting patients with the highest possibility of detecting atrial fibrillation with prolonged rhythm monitoring. The clinical relevance of short-term atrial fibrillation, the need for medical intervention and the evaluation as to whether intervention results in improved clinical outcomes should be assessed. Method: The Nordic Atrial Fibrillation and Stroke Study is an international, multicentre, prospective, observational trial evaluating the occurrence of occult atrial fibrillation in cryptogenic stroke and transient ischaemic attack. Patients with cryptogenic stroke or transient ischaemic attack from the Nordic countries are included and will have the Reveal LINQ® Insertable cardiac monitor system implanted for 12 months for atrial fibrillation detection. Biomarkers which can be used as predictors for atrial fibrillation and may identify patients, who could derive the most clinical benefit from the detection of atrial fibrillation by prolonged monitoring, are being studied. Conclusion: The primary endpoint is atrial fibrillation burden within 12 months of continuous rhythm monitoring. Secondary endpoints are atrial fibrillation burden within six months, levels of biomarkers predicting atrial fibrillation, CHA2DS2-VASc score, incidence of recurrent stroke or transient ischaemic attack, use of anticoagulation and antiarrhythmic drugs, and quality of life measurements. The clinical follow-up period is 12 months. The study started in 2017 and the completion is expected at the end of 2020.

10.
Stroke ; 50(5): 1279-1281, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31009339

RESUMO

Background and Purpose- Tenecteplase represents a promising alternative to alteplase as thrombolytic treatment in acute ischemic stroke. There are limited data on tenecteplase 0.4 mg/kg in patients with increased stroke severity. We aimed to assess safety and efficacy of tenecteplase 0.4 mg/kg in patients with moderate and severe ischemic stroke. Methods- NOR-TEST (Norwegian Tenecteplase Stroke Trial) was a phase III trial designed to investigate the safety and efficacy of tenecteplase 0.4 mg/kg versus alteplase 0.9 mg/kg in ischemic stroke. In this post hoc analysis, moderate stroke was defined as admission National Institutes of Health Stroke Scale; 6 to 14 and severe stroke as National Institutes of Health Stroke Scale; ≥15. Rates of favorable outcome at 90 days, symptomatic intracerebral hemorrhage (sICH), and mortality after 7 and 90 days were assessed. Results- In patients with moderate stroke (n=261), there were no differences in rates of favorable outcome, sICH, or mortality between tenecteplase and alteplase. In patients with severe stroke (n=87), there were no differences in outcome, frequency of sICH, or mortality at 7 days, but all-cause mortality at 90 days was increased in patients treated with tenecteplase (10 [26.3%] versus 4 [9.1%]; P=0.045). One patient died of sICH in the tenecteplase group, and 2 patients died of sICH in the alteplase group. Conclusions- Rates of favorable outcome and sICH were similar between treatment groups in patients with moderate and severe stroke. Mortality after 90 days was increased in patients with severe stroke receiving tenecteplase. Future studies assessing tenecteplase 0.4 mg/kg should monitor safety parameters closely in patients with severe stroke. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT01949948.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Índice de Gravidade de Doença , Acidente Vascular Cerebral/tratamento farmacológico , Tenecteplase/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Método Simples-Cego , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento
11.
Acta Neurol Scand ; 140(1): 3-8, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30929256

RESUMO

BACKGROUND AND PURPOSE: Recurrent ischemic stroke (IS) or TIA is frequent with a considerable variation in incidence and mortality across populations. Current data on stroke recurrence and mortality are useful to examine trends, risk factors, and treatment effects. In this study, we calculated the incidence of recurrent IS or TIA in a hospital-based stroke population in Western Norway, investigated recurrence factors, and estimated the effect of recurrence on all-cause mortality. METHODS: This prospective cohort study registered recurrence and mortality among 1872 IS and TIA survivors admitted to the stroke unit at Haukeland University Hospital between July 2007 and December 2013. Recurrence and death until September 1, 2016, were identified by medical chart review. Cumulative incidences of recurrence were estimated with a competing risks Cox model. Multivariate Cox models were used to examine recurrence factors and mortality. RESULTS: During follow-up, 220 patients had 277 recurrent IS or TIAs. The cumulative recurrence rate was 5.4% at 1 year, 11.3% at 5 years, and 14.2% at the end of follow-up. Hypertension (HR = 1.65, 95% CI 1.21-2.25), prior symptomatic stroke (HR = 1.63, 95% CI 1.18-2.24), chronic infarcts on MRI (HR = 1.48, 95% CI 1.10-1.99), and age (HR 1.02/year, 95% CI 1.00-1.03) were independently associated with recurrence. A total of 668 (35.7%) patients died during follow-up. Recurrence significantly increased the all-cause mortality (HR = 2.55, 95% CI 2.04-3.18). CONCLUSIONS: The risk of recurrent IS stroke or TIA was modest in our population and was associated with previously established risk factors. Recurrence more than doubled the all-cause mortality.


Assuntos
Ataque Isquêmico Transitório/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Isquemia Encefálica/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Noruega/epidemiologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Recidiva , Fatores de Risco
12.
Stroke ; 50(2): 498-500, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30602354

RESUMO

Background and Purpose- Thrombolysis with alteplase has beneficial effect on outcome and is safe within 4.5 hours. The present study compares the efficacy and safety of tenecteplase and alteplase in patients treated 3 to 4.5 hours after ischemic stroke. Methods- The data are from a prespecified substudy of patients included in The NOR-TEST (Norwegian Tenecteplase Stroke Trial), a randomized control trial comparing tenecteplase with alteplase. Results- The median admission National Institutes of Health Stroke Scale for this study population was 3 (interquartile range, 2-6). In the intention-to-treat analysis, 57% of patients that received tenecteplase and 53% of patients that received alteplase reached good functional outcome (modified Rankin Scale score of 0-1) at 3 months (odds ratio, 1.19; 95% CI, 0.68-2.10). The rates of intracranial hemorrhage in the first 48 hours were 5.7% in the tenecteplase group and 6.7% in the alteplase group (odds ratio, 0.84; 95% CI, 0.26-2.70). At 3 months, mortality was 5.7% and 4.5%, respectively. After excluding stroke mimics and patients with modified Rankin Scale score of >1 before stroke, the proportion of patients with good functional outcome was 61% in the tenecteplase group and 57% in the alteplase group (odds ratio, 1.24; 95% CI, 0.65-2.37). Conclusions- Tenecteplase is at least as effective as alteplase to achieve a good clinical outcome in patients with mild stroke treated between 3 and 4.5 hours after ischemic stroke. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT01949948.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Tenecteplase/administração & dosagem , Ativador de Plasminogênio Tecidual/administração & dosagem , Idoso , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Noruega , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/mortalidade , Tenecteplase/efeitos adversos , Fatores de Tempo , Ativador de Plasminogênio Tecidual/efeitos adversos
13.
Int J Stroke ; 14(5): 508-516, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30019629

RESUMO

BACKGROUND: Stroke mimics are frequently treated with thrombolysis in clinical practice and thrombolytic trials. Although alteplase in stroke mimics has proven to be safe, safety of tenecteplase in stroke mimics has not been assessed in an ischemic stroke study setting. We aimed to assess clinical characteristics and safety of stroke mimics treated with thrombolysis in the Norwegian Tenecteplase Stroke Trial. We also aimed to identify possible predictors of stroke mimics as compared to patients with acute cerebral ischemia. METHODS: Norwegian Tenecteplase Stroke Trial was a phase-3 trial investigating safety and efficacy of tenecteplase vs. alteplase in patients with suspected acute cerebral ischemia. Two groups were defined based on diagnose at discharge: patients with a different diagnose than ischemic stroke or transient ischemic attack (stroke mimics group) and patients diagnosed with ischemic stroke or transient ischemic attack (acute cerebral ischemia group). Logistic regression analyses were performed with stroke mimics vs. acute cerebral ischemia as dependent variable to identify predictors of stroke mimics. RESULTS: Of 1091 randomized patients, 181 (16.6%) were stroke mimics. Migraine (22.2%) and peripheral vertigo (11.4%) were the two most frequent stroke mimic-diagnoses. There was no symptomatic intracerebral hemorrhage in the stroke mimics group. Stroke mimics were independently associated with age ≤60 years (OR 2.75, p < 0.001), female sex (OR 1.48, p = 0.026), no history of myocardial infarction (OR 2.03, p = 0.045), systolic BP ≤ 150 mmHg (OR 2.33, p < 0.001), NIHSS ≤ 6 points (OR 1.83, p = 0.011), sensory loss (OR 1.55, p = 0.015), and no facial paresis (OR 2.41, p < 0.001) on admission. CONCLUSION: Thrombolysis with tenecteplase seems to be as safe as with alteplase in stroke mimics. Predictors were identified for stroke mimics which may contribute to differentiate stroke mimics from acute cerebral ischemia in future stroke trials.

14.
Brain Behav ; 8(10): e01108, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30222913

RESUMO

BACKGROUND: Incidence of recurrent stroke is highest within 30 days after the initial ischemic stroke (IS) or TIA, but knowledge about early recurrence is lacking. We aimed to identify etiological groups with highest risk of early recurrence and assess how the TOAST classification identified index stroke etiology. METHODS: Medical records of 1874 IS and TIA patients in the Bergen NORSTROKE registry were retrospectively reviewed for identification of recurrent IS or TIA within 30 days after index IS or TIA. Stroke etiology was determined by review of electronical medical journals. Logistic regression was used to calculate odds ratios (OR) for 30-day recurrence. RESULTS: Thirty-three patients (1.8%) were readmitted with recurrent IS or TIA within 30 days after index stroke. By using TOAST, 12 patients were initially classified with stroke of unknown etiology (SUE). Etiologies behind recurrent IS or TIA were after the recurrent episode identified as extracranial large artery atherosclerosis (LAA) in 14 patients (42.4%), intracranial arterial pathology in seven patients (21.2%), active malignancy in six patients (18.2%), and cardio embolism in four patients (12.1%). Small vessel occlusion and SUE were the causes in one patient each. Logistic regression showed that patients with stroke of other determined etiology (SOE) and LAA had increased risk of 30-day recurrence (OR = 9.72, 95% CI 1.84-51.3, p < 0.01 and OR = 4.36, 95% CI 2.01-9.47, p < 0.01, respectively). CONCLUSION: Patients with LAA and SOE had increased risk of recurrent IS or TIA within 30 days. TOAST was inadequate at identifying exact etiologies behind recurrent stroke at index event.


Assuntos
Isquemia Encefálica/diagnóstico , Ataque Isquêmico Transitório/diagnóstico , Acidente Vascular Cerebral/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Risco
15.
Science ; 360(6391)2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29798853

RESUMO

Hülsmann and Hartig suggest that ecological mechanisms other than specialized natural enemies or intraspecific competition contribute to our estimates of conspecific negative density dependence (CNDD). To address their concern, we show that our results are not the result of a methodological artifact and present a null-model analysis that demonstrates that our original findings-(i) stronger CNDD at tropical relative to temperate latitudes and (ii) a latitudinal shift in the relationship between CNDD and species abundance-persist even after controlling for other processes that might influence spatial relationships between adults and recruits.


Assuntos
Biodiversidade , Árvores , Densidade Demográfica , Plântula
16.
Science ; 360(6391)2018 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-29798855

RESUMO

Chisholm and Fung claim that our method of estimating conspecific negative density dependence (CNDD) in recruitment is systematically biased, and present an alternative method that shows no latitudinal pattern in CNDD. We demonstrate that their approach produces strongly biased estimates of CNDD, explaining why they do not detect a latitudinal pattern. We also address their methodological concerns using an alternative distance-weighted approach, which supports our original findings of a latitudinal gradient in CNDD and a latitudinal shift in the relationship between CNDD and species abundance.


Assuntos
Biodiversidade , Árvores , Ecossistema , Plântula
17.
Transl Stroke Res ; 9(4): 333-339, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29119369

RESUMO

Contrast-enhanced sonothrombolysis (CEST) seems to be a safe and promising treatment in acute ischemic stroke. It remains unknown if temporal bone features may influence the efficacy of CEST. We investigated the association between different temporal bone features on admission computed tomography (CT) scan and the outcome in acute ischemic stroke patients included in the randomized Norwegian Sonothrombolysis in Acute Stroke Study (NOR-SASS). Patients diagnosed as stroke mimics and those with infratentorial stroke or with incorrect insonation were excluded. We retrospectively assessed temporal bone heterogeneity (presence of diploë), diploë ratio, thickness, and density on admission CT scans. National institute of Health Stroke Scale (NIHSS) at 24 h and modified Rankin Scale (mRS) at 3 months were correlated with CT findings both in CEST and sham CEST patients. A total of 99 patients were included of which 52 were assigned to CEST and 47 to sham CEST. Approximately 20% patients had a heterogeneous temporal bone in both the CEST and sham CEST group. All temporal bone CT features studied were associated with female sex. In the CEST group, temporal bone heterogeneity (p = 0.006) and higher temporal bone diploë ratio (p = 0.002) were associated with higher NIHSS at 24 h. There was no association between temporal bone features and mRS at 3 months. Approximately 20% of acute ischemic stroke patients have heterogeneous temporal bone and may be resistant to standard 2-MHz transcranial Doppler ultrasound treatment. Sonothrombolysis resistance may easily be predicted by admission CT for better selection.


Assuntos
Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/terapia , Osso Temporal/diagnóstico por imagem , Terapia Trombolítica/métodos , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/complicações , Meios de Contraste/metabolismo , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Noruega , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Tomógrafos Computadorizados , Ultrassonografia Doppler Transcraniana
18.
Ecol Lett ; 21(1): 83-92, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29143434

RESUMO

Escalation (macroevolutionary increase) or divergence (disparity between relatives) in trait values are two frequent outcomes of the plant-herbivore arms race. We studied the defences and caterpillars associated with 21 sympatric New Guinean figs. Herbivore generalists were concentrated on hosts with low protease and oxidative activity. The distribution of specialists correlated with phylogeny, protease and trichomes. Additionally, highly specialised Asota moths used alkaloid rich plants. The evolution of proteases was conserved, alkaloid diversity has escalated across the studied species, oxidative activity has escalated within one clade, and trichomes have diverged across the phylogeny. Herbivore specificity correlated with their response to host defences: escalating traits largely affected generalists and divergent traits specialists; but the effect of escalating traits on extreme specialists was positive. In turn, the evolution of defences in Ficus can be driven towards both escalation and divergence in individual traits, in combination providing protection against a broad spectrum of herbivores.


Assuntos
Ficus , Herbivoria , Insetos , Animais , Fenótipo , Filogenia
19.
R Soc Open Sci ; 5(9): 181168, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30839691

RESUMO

The relationship between ß-diversity and latitude still remains to be a core question in ecology because of the lack of consensus between studies. One hypothesis for the lack of consensus between studies is that spatial scale changes the relationship between latitude and ß-diversity. Here, we test this hypothesis using tree data from 15 large-scale forest plots (greater than or equal to 15 ha, diameter at breast height ≥ 1 cm) across a latitudinal gradient (3-30o) in the Asia-Pacific region. We found that the observed ß-diversity decreased with increasing latitude when sampling local tree communities at small spatial scale (grain size ≤0.1 ha), but the observed ß-diversity did not change with latitude when sampling at large spatial scales (greater than or equal to 0.25 ha). Differences in latitudinal ß-diversity gradients across spatial scales were caused by pooled species richness (γ-diversity), which influenced observed ß-diversity values at small spatial scales, but not at large spatial scales. Therefore, spatial scale changes the relationship between ß-diversity, γ-diversity and latitude, and improving sample representativeness avoids the γ-dependence of ß-diversity.

20.
Proc Biol Sci ; 284(1866)2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29118136

RESUMO

A long-term goal in evolutionary ecology is to explain the incredible diversity of insect herbivores and patterns of host plant use in speciose groups like tropical Lepidoptera. Here, we used standardized food-web data, multigene phylogenies of both trophic levels and plant chemistry data to model interactions between Lepidoptera larvae (caterpillars) from two lineages (Geometridae and Pyraloidea) and plants in a species-rich lowland rainforest in New Guinea. Model parameters were used to make and test blind predictions for two hectares of an exhaustively sampled forest. For pyraloids, we relied on phylogeny alone and predicted 54% of species-level interactions, translating to 79% of all trophic links for individual insects, by sampling insects from only 15% of local woody plant diversity. The phylogenetic distribution of host-plant associations in polyphagous geometrids was less conserved, reducing accuracy. In a truly quantitative food web, only 40% of pair-wise interactions were described correctly in geometrids. Polyphenol oxidative activity (but not protein precipitation capacity) was important for understanding the occurrence of geometrids (but not pyraloids) across their hosts. When both foliar chemistry and plant phylogeny were included, we predicted geometrid-plant occurrence with 89% concordance. Such models help to test macroevolutionary hypotheses at the community level.


Assuntos
Cadeia Alimentar , Herbivoria , Mariposas/fisiologia , Folhas de Planta/química , Animais , Larva/crescimento & desenvolvimento , Larva/fisiologia , Modelos Biológicos , Mariposas/crescimento & desenvolvimento , Nova Guiné , Filogenia , Plantas , Floresta Úmida
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