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1.
Am Nat ; 203(4): 528-534, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38489773

RESUMO

AbstractMany animals exhibit contrast between their dorsal coloration and their ventral coloration. If selection acts differently on dorsal versus ventral coloration, ancestral covariance between these traits should break down, eventually leading to independent modules of trait evolution. Here, we compare the evolution of feather color across body regions for a clade of Australasian songbirds (Meliphagoidea). We find evidence for three modules of covarying color regions. Among these modules, ventral feathers evolve with high lability, evolving at three times the rate of dorsal plumage and 20 times the rate of flight feathers. While both dorsal plumage and ventral plumage are darker in areas with more precipitation and vegetation, we find that dorsal plumage is twice as similar to colors in satellite photos of background substrates. Overall, differential selection on ventral and dorsal colors likely maintains these as distinct modules over evolutionary timescales-a novel explanation for dorsoventral contrast in pigmentation.


Assuntos
Passeriformes , Aves Canoras , Animais , Aves Canoras/genética , Fenótipo , Pigmentação/genética , Plumas , Cor
2.
Glob Chang Biol ; 30(1): e17067, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273562

RESUMO

Climate change is increasing the frequency, intensity, and duration of extreme weather events across the globe. Understanding the capacity for ecological communities to withstand and recover from such events is critical. Typhoons are extreme weather events that are expected to broadly homogenize ecological dynamics through structural damage to vegetation and longer-term effects of salinization. Given their unpredictable nature, monitoring ecological responses to typhoons is challenging, particularly for mobile animals such as birds. Here, we report spatially variable ecological responses to typhoons across terrestrial landscapes. Using a high temporal resolution passive acoustic monitoring network across 24 sites on the subtropical island of Okinawa, Japan, we found that typhoons elicit divergent ecological responses among Okinawa's diverse terrestrial habitats, as indicated by increased spatial variability of biological sound production (biophony) and individual species detections. This suggests that soniferous communities are capable of a diversity of different responses to typhoons. That is, spatial insurance effects among local ecological communities provide resilience to typhoons at the landscape scale. Even though site-level typhoon impacts on soundscapes and bird detections were not particularly strong, monitoring at scale with high temporal resolution across a broad spatial extent nevertheless enabled detection of spatial heterogeneity in typhoon responses. Further, species-level responses mirrored those of acoustic indices, underscoring the utility of such indices for revealing insight into fundamental questions concerning disturbance and stability. Our findings demonstrate the significant potential of landscape-scale acoustic sensor networks to capture the understudied ecological impacts of unpredictable extreme weather events.


Assuntos
Tempestades Ciclônicas , Animais , Ecossistema , Mudança Climática , Aves/fisiologia , Acústica
3.
Prehosp Emerg Care ; 28(2): 271-281, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37318845

RESUMO

OBJECTIVE: Pediatric emergencies are high-stakes yet low-volume clinical encounters for emergency medical services (EMS) clinicians, necessitating innovative approaches to training. We sought to explore the acceptability, usability, and ergonomics of a novel augmented reality (AR) software for EMS crisis management training. METHODS: This was a prospective, mixed-methods study employing qualitative and quantitative analyses. We enrolled emergency medical technicians (EMTs) and paramedics at a municipal fire service in Northern California. We ran the Chariot Augmented Reality Medical simulation software (Stanford Chariot Program, Stanford University, Stanford, CA) on the ML1 headset (Magic Leap, Inc., Plantation, FL), which enabled participants to view an AR image of a patient overlaid with real-world training objects. Participants completed a simulation of a pediatric hypoglycemia-induced seizure and cardiac arrest. Participants subsequently engaged in structured focus group interviews assessing acceptability, which we coded and thematically analyzed. We evaluated the usability of the AR system and ergonomics of the ML1 headset using previously validated scales, and we analyzed findings with descriptive statistics. RESULTS: Twenty-two EMS clinicians participated. We categorized focus group interview statements into seven domains after an iterative thematic analysis: general appraisal, realism, learning efficacy, mixed reality feasibility, technology acceptance, software optimization, and alternate use cases. Participants valued the realism and the mixed reality functionality of the training simulation. They reported that AR could be effective for practicing pediatric clinical algorithms and task prioritization, building verbal communication skills, and promoting stress indoctrination. However, participants also noted challenges with integrating AR images with real-world objects, the learning curve required to adapt to the technology, and areas for software improvement. Participants favorably evaluated the ease of use of the technology and comfortability of wearing the hardware; however, most participants reported that they would need technical support. CONCLUSION: Participants positively evaluated the acceptability, usability, and ergonomics of an AR simulator for pediatric emergency management training, and participants identified current technological limitations and areas for improvement. AR simulation may serve as an effective training adjunct for prehospital clinicians.


Assuntos
Realidade Aumentada , Serviços Médicos de Emergência , Auxiliares de Emergência , Treinamento por Simulação , Humanos , Criança , Estudos Prospectivos , Simulação por Computador , Treinamento por Simulação/métodos
4.
Am J Drug Alcohol Abuse ; 50(1): 8-11, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38212992

RESUMO

Emergency medical services (EMS) can be an invaluable ally of addiction medicine clinicians, but the potential role of EMS in combating the opioid epidemic has been under-realized. EMS has historically focused on emergency response and resuscitation in cases of overdose; however, EMS is also well-positioned to build rapport with persons who use drugs (PWUD), provide harm reduction services, and connect PWUD with additional treatment services and resources. A select number of EMS organizations have begun to offer substance-related programming that extends beyond resuscitation, but these offerings remain limited in scope and impact. This perspective argues that addiction medicine clinicians can bolster the ability of EMS to provide high quality substance-related services by engaging in prehospital care education, program development and research, and clinical care. This perspective shares practical strategies for addiction medicine clinicians to partner with EMS and considers several potential barriers that must be overcome, including bureaucratic challenges, variability in the scope of practice of EMS providers across different locations, and limited funding.


Assuntos
Medicina do Vício , Overdose de Drogas , Serviços Médicos de Emergência , Humanos , Overdose de Drogas/tratamento farmacológico , Analgésicos Opioides/uso terapêutico
5.
Am J Emerg Med ; 72: 85-87, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37499554

RESUMO

Overdose fatalities are increasingly attributed to synthetic opioids, including fentanyl, which may be added to samples of illicit substances unknowingly to the user. As recently as April 2023, the Centers for Disease Control and Prevention has also raised awareness of the risks of xylazine, an animal tranquilizer that has been found in adulterated samples of illicit substance. A growing body of evidence supports the use of drug testing services, including fentanyl and xylazine test strips, to reduce the risks associated with substance use and prevent fatal overdoses. Emergency medical services clinicians serve on the frontline of the opioid epidemic and are uniquely positioned to distribute harm reduction materials. In this article, we advocate for emergency medical services to distribute fentanyl and xylazine test strips. We also critically evaluate legal and other barriers to implementation.


Assuntos
Overdose de Drogas , Heroína , Humanos , Redução do Dano , Xilazina/uso terapêutico , Analgésicos Opioides/uso terapêutico , Fentanila , Overdose de Drogas/tratamento farmacológico
6.
J Emerg Nurs ; 49(3): 431-440, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36180265

RESUMO

INTRODUCTION: Patient/visitor violence and aggression (V&A) in the emergency department occurs daily. Few interventions exist to decrease V&A. Research describing prevalence, severity, and perceived safety among ED clinicians is limited. METHODS: A descriptive survey explored V&A against ED clinicians in one urban emergency department. A sample of nurses, ED technicians, physicians and advanced practice providers participated. Participants completed a demographic survey, Personal Workplace Safety Instrument for Emergency Nurses (PWSI-EN), and ENA V&A frequency checklist. Analysis of Variance (ANOVA) for unadjusted and Analysis of Covariance (ANCOVA) for adjusted associations were used to assess differences in the PWSI-EN survey composite score and "feeling safe in the ED" among ED roles. ANCOVA was adjusted for potential confounders: sex, race, years working in emergency department, and shift worked. RESULTS: Sixty-five (46.4%) of the 140 ED clinicians returned surveys, which were almost evenly distributed between ED clinician roles and sex. Mean age was 37.2 (range: 21-64) years. All (100%) nurses and providers reported being verbally abused. More nurses reported physical violence (n = 21, 87.5%) than providers (n = 7, 36.8%) and ED technicians (n = 11, 55%). Nurses and ED technicians reported experiencing greater prevalence of physical violence than providers (P < .05). Nurses (mean 3.29, range 2.95 to 3.63) were more fearful for their personal safety than ED technicians (mean 3.88, range 3.48 to 4.28) (P < .03). DISCUSSION: V&A are common creating a fearful environment. However, little research regarding clinician perceptions exists. Our study aids in identifying areas for clinician-targeted strategies to prevent ED V&A.


Assuntos
Violência , Violência no Trabalho , Humanos , Adulto , Agressão , Inquéritos e Questionários , Gestão da Segurança , Serviço Hospitalar de Emergência , Violência no Trabalho/prevenção & controle
7.
Ecol Lett ; 25(3): 581-597, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35199922

RESUMO

Functional traits offer a rich quantitative framework for developing and testing theories in evolutionary biology, ecology and ecosystem science. However, the potential of functional traits to drive theoretical advances and refine models of global change can only be fully realised when species-level information is complete. Here we present the AVONET dataset containing comprehensive functional trait data for all birds, including six ecological variables, 11 continuous morphological traits, and information on range size and location. Raw morphological measurements are presented from 90,020 individuals of 11,009 extant bird species sampled from 181 countries. These data are also summarised as species averages in three taxonomic formats, allowing integration with a global phylogeny, geographical range maps, IUCN Red List data and the eBird citizen science database. The AVONET dataset provides the most detailed picture of continuous trait variation for any major radiation of organisms, offering a global template for testing hypotheses and exploring the evolutionary origins, structure and functioning of biodiversity.


Assuntos
Aves , Ecossistema , Animais , Biodiversidade , Evolução Biológica , Humanos , Filogenia
8.
Mol Ecol ; 29(9): 1611-1627, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31820838

RESUMO

Island biodiversity has long fascinated biologists as it typically presents tractable systems for unpicking the eco-evolutionary processes driving community assembly. In general, two recurring themes are of central theoretical interest. First, immigration, diversification, and extinction typically depend on island geographical properties (e.g., area, isolation, and age). Second, predictable ecological and evolutionary trajectories readily occur after colonization, such as the evolution of adaptive trait syndromes, trends toward specialization, adaptive radiation, and eventual ecological decline. Hypotheses such as the taxon cycle draw on several of these themes to posit particular constraints on colonization and subsequent eco-evolutionary dynamics. However, it has been challenging to examine these integrated dynamics with traditional methods. Here, we combine phylogenomics, population genomics and phenomics, to unravel community assembly dynamics among Pheidole (Hymenoptera, Formicidae) ants in the isolated Fijian archipelago. We uphold basic island biogeographic predictions that isolated islands accumulate diversity primarily through in situ evolution rather than dispersal, and population genomic support for taxon cycle predictions that endemic species have decreased dispersal ability and demography relative to regionally widespread taxa. However, rather than trending toward island syndromes, ecomorphological diversification in Fiji was intense, filling much of the genus-level global morphospace. Furthermore, while most endemic species exhibit demographic decline and reduced dispersal, we show that the archipelago is not an evolutionary dead-end. Rather, several endemic species show signatures of population and range expansion, including a successful colonization to the Cook islands. These results shed light on the processes shaping island biotas and refine our understanding of island biogeographic theory.


Assuntos
Formigas , Genômica , Ilhas , Fenômica , Animais , Formigas/genética , Biodiversidade , Evolução Biológica , Filogenia , Polinésia
9.
Proc Biol Sci ; 286(1917): 20192474, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31847778

RESUMO

While morphological traits are often associated with multiple functions, it remains unclear how evolution balances the selective effects of different functions. Birds' beaks function not only in foraging but also in thermoregulating and singing, among other behaviours. Studies of beak evolution abound, however, most focus on a single function. Hence, we quantified relative contributions of different functions over an evolutionary timescale. We measured beak shape using geometric morphometrics and compared this trait with foraging behaviour, climatic variables and song characteristics in a phylogenetic comparative study of an Australasian radiation of songbirds (Meliphagidae). We found that both climate and foraging behaviour were significantly correlated with the beak shape and size. However, foraging ecology had a greater effect on shape, and climate had a nearly equal effect on size. We also found that evolutionary changes in beak morphology had significant consequences for vocal performance: species with elongate-shaped beaks sang at higher frequencies, while species with large beaks sang at a slower pace. The evolution of the avian beak exemplifies how morphological traits can be an evolutionary compromise among functions, and suggests that specialization along any functional axis may increase ecological divergence or reproductive isolation along others.


Assuntos
Bico/anatomia & histologia , Fenótipo , Aves Canoras/fisiologia , Animais , Evolução Biológica , Regulação da Temperatura Corporal , Vocalização Animal
10.
J Anim Ecol ; 88(9): 1392-1405, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31132149

RESUMO

The classical MacArthur-Wilson theory of island biogeography (TIB) emphasizes the role of island area and isolation in determining island biotas, but is neutral with respect to species differences that could affect community assembly and persistence. Recent extensions of island biogeography theory address how functional differences among species may lead to non-random community assembly processes and different diversity-area scaling patterns. First, the trophic TIB considers how diversity scaling varies across trophic position in a community, with species at higher trophic levels being most strongly influenced by island area. Second, further extensions have predicted how trait distributions, and hence functional diversity, should scale with area. Trait-based theory predicts richness-corrected functional diversity should be low on small islands but converge to null on larger islands. Conversely, competitive assembly predicts high diversity on small islands converging to null with increasing size. However, despite mounting interest in diversity-area relationships across different dimensions of diversity, these predictions derived from theory have not been extensively tested across taxa and island systems. Here, we develop and test predictions of the trophic TIB and extensions to functional traits, by examining the diversity-area relationship across multiple trophic ranks and dimensions of avian biodiversity in the Ryukyu archipelago of Japan. We find evidence for a positive species- and phylogenetic diversity-area relationship, but functional diversity was not strongly affected by island area. Counter to the trophic TIB, we found no differences in the slopes of species-area relationships among trophic ranks, although slopes varied among trophic guilds at the same rank. We revealed differential assembly of trophic ranks, with evidence of trait-based assembly of intermediate predators but otherwise neutral community assembly. Our results suggest that niche space differs among trophic guilds of birds, but that differences are mostly not predicted by current extensions of island biogeography theory. While predicted patterns do not fit the empirical data well in this case, the development of such theory provides a useful framework to analyse island patterns from new perspectives. The application of empirical datasets such as ours should help provide a basis for developing further iterations of island biogeography theory.


Assuntos
Biodiversidade , Modelos Biológicos , Animais , Aves , Ilhas , Japão , Filogenia
13.
Int J Radiat Oncol Biol Phys ; 117(3): 630-640, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37201758

RESUMO

PURPOSE: Molecular imaging better identifies anatomic regions of metastatic spread of prostate cancer compared with conventional imaging, resulting in para-aortic (PA) nodal metastases being increasingly identified. Consequently, some radiation oncologists electively treat the PA lymph node region in patients with gross or high risk of PA nodal involvement. The anatomic locations of at-risk PA lymph nodes for prostate cancer are unknown. Our objective was to use molecular imaging to develop guidelines for the optimal delineation of the PA clinical target volume (CTV) in patients with prostate cancer. METHODS AND MATERIALS: We conducted a multi-institutional retrospective cohort study of patients with prostate cancer undergoing 18F-fluciclovine or 18F-DCFPyL prostate-specific membrane antigen positron emission tomography (PET)/computed tomography (CT). Images of patients with PET-positive PA nodes were imported into the treatment planning system, avid nodes were contoured, and measurements were taken in relation to anatomic landmarks. A contouring guideline that encompassed the location of ≥95% of PET-positive PA nodes was created using descriptive statistics and then validated in an independent data set. RESULTS: Five hundred fifty-nine patients had molecular PET/CT imaging in the development data set (78% 18F-fluciclovine, 22% prostate-specific membrane antigen). Seventy-six patients (14%) had evidence of PA nodal metastasis. We determined that expanding the CTV to 1.8 cm left of the aorta, 1.4 cm right of the inferior vena cava (IVC), 7 mm posterior to the aorta/IVC or to the vertebral body, and superiorly to the T11/T12 vertebral interface, with the anterior border 4 mm anterior to the aorta/IVC and inferior border at the bifurcation of the aorta/IVC, resulted in coverage of ≥95% of PET-positive PA nodes. When the guideline was used in the independent validation data set (246 patients with molecular PET/CT imaging, of whom 31 had PA nodal metastasis), 97% of nodes were encompassed, thereby validating our guideline. CONCLUSIONS: We used molecular PET/CT imaging to determine the anatomic locations of PA metastases to develop contouring guidelines for creating a prostate cancer PA CTV. Although the optimal patient selection and clinical benefits of PA radiation therapy remain uncertain, our results will aid in delineating the optimal target when PA radiation therapy is pursued.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Masculino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Retrospectivos , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/radioterapia , Metástase Linfática/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/patologia , Imagem Molecular
14.
Evolution ; 77(12): 2656-2671, 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-37801637

RESUMO

The causes of population divergence in vagile groups remain a paradox in evolutionary biology: dispersive species should be able to colonize new areas, a prerequisite for allopatric speciation, but dispersal also facilitates gene flow, which erodes population differentiation. Strong dispersal ability has been suggested to enhance divergence in patchy habitats and inhibit divergence in continuous landscapes, but empirical support for this hypothesis is lacking. Here we compared patterns of population divergence in a dispersive clade of swallows distributed across both patchy and continuous habitats. The Pacific Swallow (Hirundo tahitica) has an insular distribution throughout Southeast Asia and the Pacific, while its sister species, the Welcome Swallow (H. neoxena), has a continental distribution in Australia. We used whole-genome data to demonstrate strong genetic structure and limited introgression among insular populations, but not among continental populations. Demographic models show that historic changes in habitat connectivity have contributed to population structure within the clade. Swallows appear to exhibit evolutionarily labile dispersal behavior in which they reduce dispersal propensity after island colonization despite retaining strong flight ability. Our data support the hypothesis that fragmented habitats enhance population differentiation in vagile groups, and suggest that labile dispersal behavior is a key mechanism underlying this pattern.


Assuntos
Andorinhas , Animais , Andorinhas/genética , Ecossistema , Evolução Biológica , Austrália , Filogenia , Fluxo Gênico
15.
J Am Coll Health ; : 1-3, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35943954

RESUMO

As college and university campuses re-open during the COVID-19 pandemic, there is increased concern for mental health crises. Current trends in campus mental health care emphasize providing quality care in a safe, non-judgmental, and non-punitive manner. Collegiate-based emergency medical services organizations are well-positioned to respond to acute mental health crises on college campuses. Campus health professionals and administrators seeking to promote a health-centered approach toward mental health crises should support the growth and development of collegiate-based emergency medical services organizations.

16.
J Am Coll Health ; : 1-4, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35472006

RESUMO

OBJECTIVE: The objective of this study was to identify out-of-hospital cardiac arrest characteristics for patients treated by collegiate-based emergency medical services (CBEMS) organizations. PARTICIPANTS: CBEMS organizations provided data via the National Collegiate EMS Foundation Cardiac Arrest Data Registry. METHODS: CBEMS organization details, patient demographics, cardiac arrest characteristics and treatments, and prehospital outcomes for cases spanning October 2007 to May 2020 were analyzed with descriptive statistics. RESULTS: There were 65 OHCA entries. The majority were for male patients (82%) and a notable number of cases occurred in patients 45 years of age or younger (41%). Cases were frequently witnessed (71%) with high rates of bystander cardiopulmonary resuscitation (57%) and defibrillation (29%) prior to EMS arrival. Almost half of the patients (48%) had achieved return of spontaneous circulation until care was transferred to a provider of equal/higher level. CONCLUSIONS: CBEMS organizations may be well situated to respond rapidly to on-campus OHCAs.

17.
Ecol Evol ; 11(17): 11839-11851, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34522345

RESUMO

Vegetation complexity is an important predictor of animal species diversity. Specifically, taller vegetation should provide more potential ecological niches and thus harbor communities with higher species richness and functional diversity (FD). Resource use behavior is an especially important functional trait because it links species to their resource base with direct relevance to niche partitioning. However, it is unclear how exactly the diversity of resource use behavior changes with vegetation complexity. To address this question, we studied avian FD in relation to vegetation complexity along a continental-scale vegetation gradient. We quantified foraging behavior of passerine birds in terms of foraging method and substrate use at 21 sites (63 transects) spanning 3,000 km of woodlands and forests in Australia. We also quantified vegetation structure on 630 sampling points at the same sites. Additionally, we measured morphological traits for all 111 observed species in museum collections. We calculated individual-based, abundance-weighted FD in morphology and foraging behavior and related it to species richness and vegetation complexity (indexed by canopy height) using structural equation modeling, rarefaction analyses, and distance-based metrics. FD of morphology and foraging methods was best predicted by species richness. However, FD of substrate use was best predicted by canopy height (ranging 10-30 m), but only when substrates were categorized with fine resolution (17 categories), not when categorized coarsely (8 categories). These results suggest that, first, FD might increase with vegetation complexity independently of species richness, but whether it does so depends on the studied functional trait. Second, patterns found might be shaped by how finely we categorize functional traits. More complex vegetation provided larger "ecological space" with more resources, allowing the coexistence of more species with disproportionately more diverse foraging substrate use. We suggest that the latter pattern was driven by nonrandom accumulation of functionally distinct species with increasing canopy height.

18.
Ecol Evol ; 11(11): 6104-6118, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34141206

RESUMO

Ants use their mandibles for a wide variety of tasks related to substrate manipulation, brood transport, food processing, and colony defense. Due to constraints involved in colony upkeep, ants evolved a remarkable diversity of mandibular forms, often related to specific roles such as specialized hunting and seed milling. Considering these varied functional demands, we focused on understanding how the mandible and head shape vary within and between Pheidole subcastes. Using x-ray microtomography and 3D geometric morphometrics, we tested whether these structures are integrated and modular, and how ecological predictors influenced these features. Our results showed that mandible and head shape of majors and minor workers tend to vary from robust to slender, with some more complex changes related to the mandibular base. Additionally, we found that head and mandible shapes are characterized by a high degree of integration, but with little correlation with feeding and nesting habits. Our results suggest that a combination of structural (allometric) constraints and the behavioral flexibility conferred by subcaste dimorphism might largely buffer selective pressures that would otherwise lead to a fine-tuning between ecological conditions and morphological adaptation.

19.
Mol Phylogenet Evol ; 56(1): 419-27, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20363347

RESUMO

Darwin's vision of a "Tree of Life" showing evolutionary relationships among all extant species seems an increasingly feasible goal, at least for vertebrate animals. However, virtually all published molecular phylogenies for closely related animals are based on a single locus - maternally inherited mitochondrial DNA. New approaches using multiple nuclear loci are needed to test published trees and better resolve the twigs of the entire tree of life. Here we use New World orioles (Icterus) to test an approach based on combined analysis of six independent Z chromosome introns. Combined analysis of multiple introns using traditional phylogenetic methods resolved a well-supported species phylogeny of New World orioles. In fact, all major lineages of orioles and several sub-clades that are well-supported by previously published mtDNA data are also strongly supported by the combined nuclear Z-intron tree. The male-biased Z-intron tree presented here is overwhelmingly congruent with the female-exclusive mtDNA tree. A slow rate of mutation relative to mtDNA resulted in generally poorly resolved gene trees when intron loci were analyzed separately. However, strong phylogenetic signal for all but the most recent divergences emerged once multiple loci were concatenated and analyzed in combination. Although there clearly are conditions under which concatenation analysis of nuclear DNA can be misleading, the congruence between mitochondrial and nuclear estimates of the Icterus phylogeny suggests that concatenation remains a powerful tool for inferring phylogenetic relationships for all but very recent divergences.


Assuntos
Evolução Molecular , Filogenia , Aves Canoras/classificação , Animais , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Feminino , Íntrons/genética , Funções Verossimilhança , Masculino , Modelos Genéticos , Alinhamento de Sequência , Análise de Sequência de DNA , Aves Canoras/genética
20.
J Nucl Med ; 61(10): 1413-1418, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32764121

RESUMO

PET neuroimaging of amyloid-ß (Aß) provides an in vivo biomarker for pathologic changes associated with Alzheimer disease (AD). Aß-targeted agents have been approved by the Food and Drug Administration, with additional agents, most notably targeting tau, currently under clinical investigation and one approved in May 2020. These agents, along with nonscintigraphic biomarkers from blood and cerebrospinal fluid, have provided an opportunity to investigate the pathogenesis, prodromal changes, and time course of the disease in living individuals. The current understanding is that the neuropathologic changes of the AD continuum begin up to 25 y before the onset of clinical symptomatology. The opportunities afforded by in vivo biomarkers of AD, whether by serum, cerebrospinal fluid examination or PET, have transformed the design of AD therapeutic trials by shifting focus to the preclinical stages of disease. Future disease-modifying therapies, should they be forthcoming, will rely heavily on the use of approved biomarkers or biomarkers currently under investigation to confirm the presence of target pathology. Understanding the progressive neuropathologic changes that occur in AD-and how scintigraphic findings relate to these changes-will help the interpreting physician to fully appreciate the implications of the scintigraphic findings and provide a basis to interpret the examinations. The recently adopted National Institute on Aging-Alzheimer Association guidelines define postmortem AD neuropathologic changes as a composite score based on 3 elements. These elements are the extent of involvement (spread) by cerebral Aß based on the progression model defined by the Thal Aß phases, the extent of involvement (spread) by neurofibrillary tangles (composed of hyperphosphorylated tau proteins) based on the progression model defined by Braak, and the Consortium to Establish a Registry for Alzheimer's Disease score, which describes the density of neuritic plaques based on certain key locations in the neocortex. This paper will review the 3 elements that define the National Institute on Aging-Alzheimer's Association scoring system and discusses current evidence on how these elements relate to findings based on Aß and tau PET scintigraphy.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/metabolismo , Encéfalo/patologia , Tomografia por Emissão de Pósitrons/métodos , Proteínas tau/metabolismo , Doença de Alzheimer/etiologia , Doença de Alzheimer/patologia , Biomarcadores , Humanos , Emaranhados Neurofibrilares/metabolismo , Neuroimagem
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