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1.
Viruses ; 16(4)2024 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-38675988

RESUMO

Sosuga virus (SOSV), a rare human pathogenic paramyxovirus, was first discovered in 2012 when a person became ill after working in South Sudan and Uganda. During an ecological investigation, several species of bats were sampled and tested for SOSV RNA and only one species, the Egyptian rousette bat (ERBs; Rousettus aegyptiacus), tested positive. Since that time, multiple other species have been sampled and ERBs in Uganda have continued to be the only species of bat positive for SOSV infection. Subsequent studies of ERBs with SOSV demonstrated that ERBs are a competent host for SOSV and shed this infectious virus while exhibiting only minor infection-associated pathology. Following the 2014 Ebola outbreak in West Africa, surveillance efforts focused on discovering reservoirs for zoonotic pathogens resulted in the capture and testing of many bat species. Here, SOSV RNA was detected by qRT-PCR only in ERBs captured in the Moyamba District of Sierra Leone in the central region of the country. These findings represent a substantial range extension from East Africa to West Africa for SOSV, suggesting that this paramyxovirus may occur in ERB populations throughout its sub-Saharan African range.


Assuntos
Quirópteros , Animais , Quirópteros/virologia , Serra Leoa/epidemiologia , Infecções por Paramyxoviridae/veterinária , Infecções por Paramyxoviridae/virologia , Infecções por Paramyxoviridae/epidemiologia , RNA Viral/genética , Filogenia , Reservatórios de Doenças/virologia , Humanos
2.
Viruses ; 16(3)2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38543706

RESUMO

Following an Argentine Hemorrhagic Fever (AHF) outbreak in the early 1990s, a rodent survey for Junín virus, a New World Clade B arenavirus, in endemic areas of Argentina was conducted. Since 1990, INEVH has been developing eco-epidemiological surveillance of rodents, inside and outside the Argentine Hemorrhagic Fever endemic area. Samples from rodents captured between 1993 and 2019 that were positive for Arenavirus infection underwent Sanger and unbiased, Illumina-based high-throughput sequencing, which yielded 5 complete and 88 partial Mammarenaviruses genomes. Previously, 11 genomes representing four species of New World arenavirus Clade C existed in public records. This work has generated 13 novel genomes, expanding the New World arenavirus Clade C to 24 total genomes. Additionally, two genomes exhibit sufficient genetic diversity to be considered a new species, as per ICTV guidelines (proposed name Mammarenavirus vellosense). The 13 novel genomes exhibited reassortment between the small and large segments in New World Mammarenaviruses. This work demonstrates that Clade C Mammarenavirus infections circulate broadly among Necromys species in the Argentine Hemorrhagic Fever endemic area; however, the risk for Clade C Mammarenavirus human infection is currently unknown.


Assuntos
Arenaviridae , Arenavirus , Arenavirus do Novo Mundo , Febre Hemorrágica Americana , Vírus Junin , Animais , Humanos , Arenaviridae/genética , Roedores , Febre Hemorrágica Americana/epidemiologia , Argentina/epidemiologia , Arenavirus do Novo Mundo/genética , Vírus Junin/genética , Arenavirus/genética
3.
Emerg Infect Dis ; 30(4): 817-821, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38526320

RESUMO

Orthohantaviruses cause hantavirus cardiopulmonary syndrome; most cases occur in the southwest region of the United States. We discuss a clinical case of orthohantavirus infection in a 65-year-old woman in Michigan and the phylogeographic link of partial viral fragments from the patient and rodents captured near the presumed site of infection.


Assuntos
Infecções por Hantavirus , Orthohantavírus , Feminino , Humanos , Idoso , Michigan/epidemiologia , Filogeografia , Síndrome
5.
Viruses ; 15(11)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-38005885

RESUMO

Hantaviruses zoonotically infect humans worldwide with pathogenic consequences and are mainly spread by rodents that shed aerosolized virus particles in urine and feces. Bioinformatics methods for hantavirus diagnostics, genomic surveillance and epidemiology are currently lacking a comprehensive approach for data sharing, integration, visualization, analytics and reporting. With the possibility of hantavirus cases going undetected and spreading over international borders, a significant reporting delay can miss linked transmission events and impedes timely, targeted public health interventions. To overcome these challenges, we built HantaNet, a standalone visualization engine for hantavirus genomes that facilitates viral surveillance and classification for early outbreak detection and response. HantaNet is powered by MicrobeTrace, a browser-based multitool originally developed at the Centers for Disease Control and Prevention (CDC) to visualize HIV clusters and transmission networks. HantaNet integrates coding gene sequences and standardized metadata from hantavirus reference genomes into three separate gene modules for dashboard visualization of phylogenetic trees, viral strain clusters for classification, epidemiological networks and spatiotemporal analysis. We used 85 hantavirus reference datasets from GenBank to validate HantaNet as a classification and enhanced visualization tool, and as a public repository to download standardized sequence data and metadata for building analytic datasets. HantaNet is a model on how to deploy MicrobeTrace-specific tools to advance pathogen surveillance, epidemiology and public health globally.


Assuntos
Doenças Transmissíveis , Infecções por Hantavirus , Orthohantavírus , Animais , Humanos , Orthohantavírus/genética , Filogenia , Infecções por Hantavirus/epidemiologia , Doenças Transmissíveis/epidemiologia , Surtos de Doenças , Genômica , Roedores
6.
Sci Rep ; 13(1): 14340, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658206

RESUMO

A central assumption in the behavioral sciences is that choice behavior generalizes enough across individuals that measurements from a sampled group can predict the behavior of the population. Following from this assumption, the unit of behavioral sampling or measurement for most neuroimaging studies is the individual; however, cognitive neuroscience is increasingly acknowledging a dissociation between neural activity that predicts individual behavior and that which predicts the average or aggregate behavior of the population suggesting a greater importance of individual differences than is typically acknowledged. For instance, past work has demonstrated that some, but not all, of the neural activity observed during value-based decision-making is able to predict not just individual subjects' choices but also the success of products on large, online marketplaces-even when those two behavioral outcomes deviate from one another-suggesting that some neural component processes of decision-making generalize to aggregate market responses more readily across individuals than others do. While the bulk of such research has highlighted affect-related neural responses (i.e. in the nucleus accumbens) as a better predictor of group-level behavior than frontal cortical activity associated with the integration of more idiosyncratic choice components, more recent evidence has implicated responses in visual cortical regions as strong predictors of group preference. Taken together, these findings suggest a role of neural responses during early perception in reinforcing choice consistency across individuals and raise fundamental scientific questions about the role sensory systems in value-based decision-making processes. We use a multivariate pattern analysis approach to show that single-trial visually evoked electroencephalographic (EEG) activity can predict individual choice throughout the post-stimulus epoch; however, a nominally sparser set of activity predicts the aggregate behavior of the population. These findings support an account in which a subset of the neural activity underlying individual choice processes can scale to predict behavioral consistency across people, even when the choice behavior of the sample does not match the aggregate behavior of the population.


Assuntos
Neurociência Cognitiva , Potenciais Evocados , Humanos , Eletroencefalografia , Lobo Frontal , Individualidade
7.
Mem Cognit ; 51(8): 1898-1910, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37165298

RESUMO

Most listeners can determine when a familiar recording of music has been shifted in musical key by as little as one semitone (e.g., from B to C major). These findings appear to suggest that absolute pitch memory is widespread in the general population. However, the use of familiar recordings makes it unclear whether these findings genuinely reflect absolute melody-key associations for at least two reasons. First, listeners may be able to use spectral cues from the familiar instrumentation of the recordings to determine when a familiar recording has been shifted in pitch. Second, listeners may be able to rely solely on pitch height cues (e.g., relying on a feeling that an incorrect recording sounds "too high" or "too low"). Neither of these strategies would require an understanding of pitch chroma or musical key. The present experiments thus assessed whether listeners could make accurate absolute melody-key judgments when listening to novel versions of these melodies, differing from the iconic recording in timbre (Experiment 1) or timbre and octave (Experiment 2). Listeners in both experiments were able to select the correct-key version of the familiar melody at rates that were well above chance. These results fit within a growing body of research supporting the idea that most listeners, regardless of formal musical training, have robust representations of absolute pitch - based on pitch chroma - that generalize to novel listening situations. Implications for theories of auditory pitch memory are discussed.


Assuntos
Percepção Auditiva , Música , Humanos , Julgamento , Sinais (Psicologia) , Emoções , Percepção da Altura Sonora
8.
Atten Percept Psychophys ; 85(2): 525-542, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36690914

RESUMO

Absolute pitch (AP) is the rare ability to name any musical note without the use of a reference note. Given that genuine AP representations are based on the identification of isolated notes by their tone chroma, they are considered to be invariant to (1) surrounding tonal context, (2) changes in instrumental timbre, and (3) changes in octave register. However, there is considerable variability in the literature in terms of how AP is trained and tested along these dimensions, making recent claims about AP learning difficult to assess. Here, we examined the effect of tonal context on participant success with a single-note identification training paradigm, including how learning generalized to an untested instrument and octave. We found that participants were able to rapidly learn to distinguish C from other notes, with and without feedback and regardless of the tonal context in which C was presented. Participants were also able to partly generalize this skill to an untrained instrument. However, participants displayed the weakest generalization in recognizing C in a higher octave. The results indicate that participants were likely attending to pitch height in addition to pitch chroma - a conjecture that was supported by analyzing the pattern of response errors. These findings highlight the complex nature of note representation in AP, which requires note identification across contexts, going beyond the simple storage of a note fundamental. The importance of standardizing testing that spans both timbre and octave in assessing AP and further implications on past literature and future work are discussed.


Assuntos
Música , Humanos , Estimulação Acústica/métodos , Aprendizagem/fisiologia , Generalização Psicológica , Percepção da Altura Sonora/fisiologia , Discriminação da Altura Tonal/fisiologia
9.
J Cogn Neurosci ; 34(3): 425-444, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34942645

RESUMO

The ability to generalize across specific experiences is vital for the recognition of new patterns, especially in speech perception considering acoustic-phonetic pattern variability. Indeed, behavioral research has demonstrated that listeners are able via a process of generalized learning to leverage their experiences of past words said by difficult-to-understand talker to improve their understanding for new words said by that talker. Here, we examine differences in neural responses to generalized versus rote learning in auditory cortical processing by training listeners to understand a novel synthetic talker. Using a pretest-posttest design with EEG, participants were trained using either (1) a large inventory of words where no words were repeated across the experiment (generalized learning) or (2) a small inventory of words where words were repeated (rote learning). Analysis of long-latency auditory evoked potentials at pretest and posttest revealed that rote and generalized learning both produced rapid changes in auditory processing, yet the nature of these changes differed. Generalized learning was marked by an amplitude reduction in the N1-P2 complex and by the presence of a late negativity wave in the auditory evoked potential following training; rote learning was marked only by temporally later scalp topography differences. The early N1-P2 change, found only for generalized learning, is consistent with an active processing account of speech perception, which proposes that the ability to rapidly adjust to the specific vocal characteristics of a new talker (for which rote learning is rare) relies on attentional mechanisms to selectively modify early auditory processing sensitivity.


Assuntos
Percepção da Fala , Estimulação Acústica , Percepção Auditiva , Potenciais Evocados Auditivos/fisiologia , Humanos , Aprendizagem , Fonética , Percepção da Fala/fisiologia
10.
Virus Evol ; 7(1): veaa062, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34422315

RESUMO

Despite near-annual human outbreaks of Nipah virus (NiV) disease in Bangladesh, typically due to individual spillover events from the local bat population, only twenty whole-genome NiV sequences exist from humans and ten from bats. NiV whole-genome sequences from annual outbreaks have been challenging to generate, primarily due to the low viral load in human throat swab and serum specimens. Here, we used targeted enrichment with custom NiV-specific probes and generated thirty-five additional unique full-length genomic sequences directly from human specimens and viral isolates. We inferred the temporal and geographic evolutionary history of NiV in Bangladesh and expanded a tool to visualize NiV spatio-temporal spread from a Bayesian continuous diffusion analysis. We observed that strains from Bangladesh segregated into two distinct clades that have intermingled geographically in Bangladesh over time and space. As these clades expanded geographically and temporally, we did not observe evidence for significant branch and site-specific selection, except for a single site in the Henipavirus L polymerase. However, the Bangladesh 1 and 2 clades are differentiated by mutations initially occurring in the polymerase, with additional mutations accumulating in the N, G, F, P, and L genes on external branches. Modeling the historic geographical and temporal spread demonstrates that while widespread, NiV does not exhibit significant genetic variation in Bangladesh. Thus, future public health measures should address whether NiV within in the bat population also exhibits comparable genetic variation, if zoonotic transmission results in a genetic bottleneck and if surveillance techniques are detecting only a subset of NiV.

11.
Sci Rep ; 11(1): 14290, 2021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34253760

RESUMO

The frequency-following response (FFR) provides a measure of phase-locked auditory encoding in humans and has been used to study subcortical processing in the auditory system. While effects of experience on the FFR have been reported, few studies have examined whether individual differences in early sensory encoding have measurable effects on human performance. Absolute pitch (AP), the rare ability to label musical notes without reference notes, provides an excellent model system for testing how early neural encoding supports specialized auditory skills. Results show that the FFR predicts pitch labelling performance better than traditional measures related to AP (age of music onset, tonal language experience, pitch adjustment and just-noticeable-difference scores). Moreover, the stimulus type used to elicit the FFR (tones or speech) impacts predictive performance in a manner that is consistent with prior research. Additionally, the FFR predicts labelling performance for piano tones better than unfamiliar sine tones. Taken together, the FFR reliably distinguishes individuals based on their explicit pitch labeling abilities, which highlights the complex dynamics between sensory processing and cognition.


Assuntos
Percepção Auditiva/fisiologia , Comportamento , Audição/fisiologia , Percepção da Altura Sonora/fisiologia , Estimulação Acústica/métodos , Adulto , Eletrofisiologia , Feminino , Humanos , Individualidade , Idioma , Masculino , Modelos Estatísticos , Música , Análise de Regressão , Reprodutibilidade dos Testes , Adulto Jovem
12.
PLoS One ; 15(12): e0244308, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33370349

RESUMO

Many human behaviors are discussed in terms of discrete categories. Quantizing behavior in this fashion may provide important traction for understanding the complexities of human experience, but it also may bias understanding of phenomena and associated mechanisms. One example of this is absolute pitch (AP), which is often treated as a discrete trait that is either present or absent (i.e., with easily identifiable near-perfect "genuine" AP possessors and at-chance non-AP possessors) despite emerging evidence that pitch-labeling ability is not all-or-nothing. We used a large-scale online assessment to test the discrete model of AP, specifically by measuring how intermediate performers related to the typically defined "non-AP" and "genuine AP" populations. Consistent with prior research, individuals who performed at-chance (non-AP) reported beginning musical instruction much later than the near-perfect AP participants, and the highest performers were more likely to speak a tonal language than were the lowest performers (though this effect was not as statistically robust as one would expect from prior research). Critically, however, these developmental factors did not differentiate the near-perfect AP performers from the intermediate AP performers. Gaussian mixture modeling supported the existence of two performance distributions-the first distribution encompassed both the intermediate and near-perfect AP possessors, whereas the second distribution encompassed only the at-chance participants. Overall, these results provide support for conceptualizing intermediate levels of pitch-labeling ability along the same continuum as genuine AP-level pitch labeling ability-in other words, a continuous distribution of AP skill among all above-chance performers rather than discrete categories of ability. Expanding the inclusion criteria for AP makes it possible to test hypotheses about the mechanisms that underlie this ability and relate this ability to more general cognitive mechanisms involved in other abilities.


Assuntos
Biometria/métodos , Discriminação da Altura Tonal/fisiologia , Estimulação Acústica/métodos , Adulto , Percepção Auditiva/fisiologia , Feminino , Humanos , Idioma , Masculino , Música/psicologia , Percepção da Altura Sonora/fisiologia
13.
J Infect Dis ; 221(Suppl 4): S460-S470, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32108876

RESUMO

The error-prone nature of RNA-dependent RNA polymerases drives the diversity of RNA virus populations. Arising within this diversity is a subset of defective viral genomes that retain replication competency, termed defective interfering (DI) genomes. These defects are caused by aberrant viral polymerase reinitiation on the same viral RNA template (deletion DI species) or the nascent RNA strand (copyback DI species). DI genomes have previously been shown to alter the dynamics of a viral population by interfering with normal virus replication and/or by stimulating the innate immune response. In this study, we investigated the ability of artificially produced DI genomes to inhibit Nipah virus (NiV), a highly pathogenic biosafety level 4 paramyxovirus. High multiplicity of infection passaging of both NiV clinical isolates and recombinant NiV in Vero cells generated an extensive DI population from which individual DIs were identified using next-generation sequencing techniques. Assays were established to generate and purify both naturally occurring and in silico-designed DIs as fully encapsidated, infectious virus-like particles termed defective interfering particles (DIPs). We demonstrate that several of these NiV DIP candidates reduced NiV titers by up to 4 logs in vitro. These data represent a proof-of-principle that a therapeutic application of DIPs to combat NiV infections may be an alternative source of antiviral control for this disease.


Assuntos
Genoma Viral , Vírus Nipah/genética , Vírus Nipah/fisiologia , Animais , Linhagem Celular , Chlorocebus aethiops , Cricetinae , Vírus Defeituosos , Mesocricetus , Replicação Viral/genética , Replicação Viral/fisiologia
14.
Brain Lang ; 201: 104722, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31835154

RESUMO

Adjusting to the vocal characteristics of a new talker is important for speech recognition. Previous research has indicated that adjusting to talker differences is an active cognitive process that depends on attention and working memory (WM). These studies have not examined how talker variability affects perception and neural responses in fluent speech. Here we use source analysis from high-density EEG to show that perceiving fluent speech in which the talker changes recruits early involvement of parietal and temporal cortical areas, suggesting functional involvement of WM and attention in talker normalization. We extend these findings to acoustic source change in general by examining understanding environmental sounds in spoken sentence context. Though there may be differences in cortical recruitment to processing demands for non-speech sounds versus a changing talker, the underlying mechanisms are similar, supporting the view that shared cognitive-general mechanisms assist both talker normalization and speech-to-nonspeech transitions.


Assuntos
Córtex Cerebral/fisiologia , Percepção da Fala , Adulto , Atenção , Compreensão , Feminino , Humanos , Masculino , Memória de Curto Prazo , Acústica da Fala , Voz
15.
PLoS One ; 14(9): e0223047, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31550277

RESUMO

Absolute pitch (AP), the rare ability to name any musical note without the aid of a reference note, is thought to depend on an early critical period of development. Although recent research has shown that adults can improve AP performance in a single training session, the best learners still did not achieve note classification levels comparable to performance of a typical, "genuine" AP possessor. Here, we demonstrate that these "genuine" levels of AP performance can be achieved within eight weeks of training for at least some adults, with the best learner passing all measures of AP ability after training and retaining this knowledge for at least four months after training. Alternative explanations of these positive results, such as improving accuracy through adopting a slower, relative pitch strategy, are not supported based on joint analyses of response time and accuracy. The results also did not appear to be driven by extreme familiarity with a single instrument or octave range, as the post-training AP assessments used eight different timbres and spanned over seven octaves. Yet, it is also important to note that a majority of the participants only exhibited modest improvements in performance, suggesting that adult AP learning is difficult and that near-perfect levels of AP may only be achievable by subset of adults. Overall, these results demonstrate that explicit perceptual training in some adults can lead to AP performance that is behaviorally indistinguishable from AP that manifests within a critical period of development. Implications for theories of AP acquisition are discussed.


Assuntos
Aprendizagem/fisiologia , Música , Discriminação da Altura Tonal/fisiologia , Estimulação Acústica , Adolescente , Adulto , Feminino , Humanos , Masculino , Tempo de Reação , Adulto Jovem
16.
Cogn Sci ; 43(5): e12734, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31087588

RESUMO

People across the world seek out beautiful sounds in nature, such as a babbling brook or a nightingale song, for positive human experiences. However, it is unclear whether this positive aesthetic response is driven by a preference for the perceptual features typical of nature sounds versus a higher-order association of nature with beauty. To test these hypotheses, participants provided aesthetic judgments for nature and urban soundscapes that varied on ease of recognition. Results demonstrated that the aesthetic preference for nature soundscapes was eliminated for the sounds hardest to recognize, and moreover the relationship between aesthetic ratings and several measured acoustic features significantly changed as a function of recognition. In a follow-up experiment, requiring participants to classify these difficult-to-identify sounds into nature or urban categories resulted in a robust preference for nature sounds and a relationship between aesthetic ratings and our measured acoustic features that was more typical of easy-to-identify sounds. This pattern of results was replicated with computer-generated artificial noises, which acoustically shared properties with the nature and urban soundscapes but by definition did not come from these environments. Taken together, these results support the conclusion that the recognition of a sound as either natural or urban dynamically organizes the relationship between aesthetic preference and perceptual features and that these preferences are not inherent to the acoustic features. Implications for nature's role in cognitive and affective restoration are discussed.


Assuntos
Atenção/fisiologia , Percepção Auditiva/fisiologia , Estética , Estimulação Acústica , Feminino , Humanos , Masculino
17.
J Virol ; 93(13)2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30971476

RESUMO

In 2011, ticks were collected from livestock following an outbreak of Crimean Congo hemorrhagic fever (CCHF) in Gujarat state, India. CCHF-negative Hyalomma anatolicum tick pools were passaged for virus isolation, and two virus isolates were obtained, designated Karyana virus (KARYV) and Kundal virus (KUNDV), respectively. Traditional reverse transcription-PCR (RT-PCR) identification of known viruses was unsuccessful, but a next-generation sequencing (NGS) approach identified KARYV and KUNDV as viruses in the Reoviridae family, Orbivirus and Coltivirus genera, respectively. Viral genomes were de novo assembled, yielding 10 complete segments of KARYV and 12 nearly complete segments of KUNDV. The VP1 gene of KARYV shared a most recent common ancestor with Wad Medani virus (WMV), strain Ar495, and based on nucleotide identity we demonstrate that it is a novel WMV strain. The VP1 segment of KUNDV shares a common ancestor with Colorado tick fever virus, Eyach virus, Tai Forest reovirus, and Tarumizu tick virus from the Coltivirus genus. Based on VP1, VP6, VP7, and VP12 nucleotide and amino acid identities, KUNDV is proposed to be a new species of Coltivirus Electron microscopy supported the classification of KARYV and KUNDV as reoviruses and identified replication morphology consistent with other orbi- and coltiviruses. The identification of novel tick-borne viruses carried by the CCHF vector is an important step in the characterization of their potential role in human and animal pathogenesis.IMPORTANCE Ticks and mosquitoes, as well Culicoides, can transmit viruses in the Reoviridae family. With the help of next-generation sequencing (NGS), previously unreported reoviruses such as equine encephalosis virus, Wad Medani virus (WMV), Kammavanpettai virus (KVPTV), and, with this report, KARYV and KUNDV have been discovered and characterized in India. The isolation of KUNDV and KARYV from Hyalomma anatolicum, which is a known vector for zoonotic pathogens, such as Crimean Congo hemorrhagic fever virus, Babesia, Theileria, and Anaplasma species, identifies arboviruses with the potential to transmit to humans. Characterization of KUNDV and KARYV isolated from Hyalomma ticks is critical for the development of specific serological and molecular assays that can be used to determine the association of these viruses with disease in humans and livestock.


Assuntos
Coltivirus/classificação , Coltivirus/isolamento & purificação , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Febre Hemorrágica da Crimeia/complicações , Orbivirus/classificação , Orbivirus/isolamento & purificação , Filogenia , Carrapatos/virologia , Animais , Chlorocebus aethiops , Coltivirus/genética , Culicidae/virologia , Genoma Viral , Vírus da Febre Hemorrágica da Crimeia-Congo/classificação , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Febre Hemorrágica da Crimeia/epidemiologia , Febre Hemorrágica da Crimeia/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Índia , Mosquitos Vetores/virologia , Orbivirus/genética , Reoviridae/classificação , Reoviridae/genética , Reoviridae/isolamento & purificação , Reoviridae/ultraestrutura , Células Vero , Ensaio de Placa Viral , Proteínas Virais/genética
18.
Sci Transl Med ; 11(485)2019 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-30918113

RESUMO

Traditional vascular grafts constructed from synthetic polymers or cadaveric human or animal tissues support the clinical need for readily available blood vessels, but often come with associated risks. Histopathological evaluation of these materials has shown adverse host cellular reactions and/or mechanical degradation due to insufficient or inappropriate matrix remodeling. We developed an investigational bioengineered human acellular vessel (HAV), which is currently being studied as a hemodialysis conduit in patients with end-stage renal disease. In rare cases, small samples of HAV were recovered during routine surgical interventions and used to examine the temporal and spatial pattern of the host cell response to the HAV after implantation, from 16 to 200 weeks. We observed a substantial influx of alpha smooth muscle actin (αSMA)-expressing cells into the HAV that progressively matured and circumferentially aligned in the HAV wall. These cells were supported by microvasculature initially formed by CD34+/CD31+ cells in the neoadventitia and later maintained by CD34-/CD31+ endothelial cells in the media and lumen of the HAV. Nestin+ progenitor cells differentiated into either αSMA+ or CD31+ cells and may contribute to early recellularization and self-repair of the HAV. A mesenchymal stem cell-like CD90+ progenitor cell population increased in number with duration of implantation. Our results suggest that host myogenic, endothelial, and progenitor cell repopulation of HAVs transforms these previously acellular vessels into functional multilayered living tissues that maintain blood transport and exhibit self-healing after cannulation injury, effectively rendering these vessels like the patient's own blood vessel.


Assuntos
Prótese Vascular , Vasos Sanguíneos/citologia , Vasos Sanguíneos/transplante , Engenharia Tecidual/métodos , Enxerto Vascular/métodos , Adulto , Idoso , Vasos Sanguíneos/crescimento & desenvolvimento , Diferenciação Celular , Movimento Celular , Células Cultivadas , Células Endoteliais/citologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miócitos de Músculo Liso/citologia , Neovascularização Fisiológica , Diálise Renal , Análise Espaço-Temporal , Células-Tronco/citologia , Alicerces Teciduais , Pesquisa Translacional Biomédica , Dispositivos de Acesso Vascular
19.
Am J Nephrol ; 49(2): 156-164, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30677763

RESUMO

BACKGROUND: Chronic hemodialysis requires a mode of vascular access through an arteriovenous fistula (AVF), a prosthetic arteriovenous graft (AVG), or a central venous catheter (CVC). AVF is recommended over AVG or CVC due to increased patency and decreased intervention rates for those that mature. AVG are preferred over CVC due to decreased infection and mortality risk. The aims of this study were to evaluate the lifespan of AVF and AVG in maturation, sustained access use, and abandonment. METHODS: The United States Renal Data System (USRDS), Medicare claims, and CROWNWeb were used to identify access placements. Patients with a first end-stage renal disease (ESRD) service from January 1, 2012 to June 30, 2014 with continuous coverage with Medicare as primary payer and ≥1 AVF or AVG placed after ESRD onset were included. Maturation was defined as the first use of the access for hemodialysis recorded in CROWNWeb. Sustained access use was defined as 3 consecutive months of use without catheter placement or replacement. Accesses that were never used at any time post-placement were considered abandoned. RESULTS: The cohort included 38,035 AVF placements and 12,789 AVG placements. Sixty-nine percent of AVF and 72% of AVG matured. Fifty-two percent of AVF and 51% of AVG achieved sustained access use. One quarter of AVF and 14% of AVG were abandoned without use as recorded in CROWNWeb. CONCLUSION: Although considered the gold standard for vascular access, only half of AVF and AVG placements achieved sustained access use. The USRDS database has inherent limitations but provides useful clinical insight into maturation, sustained use, and abandonment.


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Oclusão de Enxerto Vascular/epidemiologia , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Demandas Administrativas em Assistência à Saúde/estatística & dados numéricos , Adolescente , Adulto , Idoso , Bases de Dados Factuais/estatística & dados numéricos , Feminino , Seguimentos , Oclusão de Enxerto Vascular/etiologia , Humanos , Masculino , Medicare/estatística & dados numéricos , Pessoa de Meia-Idade , Diálise Renal/métodos , Resultado do Tratamento , Estados Unidos/epidemiologia , Grau de Desobstrução Vascular , Adulto Jovem
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