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1.
PLoS Pathog ; 17(3): e1009236, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33730096

RESUMO

Understanding the dynamics of white-nose syndrome spread in time and space is an important component for the disease epidemiology and control. We reported earlier that a novel partitivirus, Pseudogymnoascus destructans partitivirus-pa, had infected the North American isolates of Pseudogymnoascus destructans, the fungal pathogen that causes white-nose syndrome in bats. We showed that the diversity of the viral coat protein sequences is correlated to their geographical origin. Here we hypothesize that the geographical adaptation of the virus could be used as a proxy to characterize the spread of white-nose syndrome. We used over 100 virus isolates from diverse locations in North America and applied the phylogeographic analysis tool BEAST to characterize the spread of the disease. The strict clock phylogeographic analysis under the coalescent model in BEAST showed a patchy spread pattern of white-nose syndrome driven from a few source locations including Connecticut, New York, West Virginia, and Kentucky. The source states had significant support in the maximum clade credibility tree and Bayesian stochastic search variable selection analysis. Although the geographic origin of the virus is not definite, it is likely the virus infected the fungus prior to the spread of white-nose syndrome in North America. We also inferred from the BEAST analysis that the recent long-distance spread of the fungus to Washington had its root in Kentucky, likely from the Mammoth cave area and most probably mediated by a human. The time to the most recent common ancestor of the virus is estimated somewhere between the late 1990s to early 2000s. We found the mean substitution rate of 2 X 10-3 substitutions per site per year for the virus which is higher than expected given the persistent lifestyle of the virus, and the stamping-machine mode of replication. Our approach of using the virus as a proxy to understand the spread of white-nose syndrome could be an important tool for the study and management of other infectious diseases.


Assuntos
Ascomicetos/virologia , Quirópteros/virologia , Nariz/virologia , Filogeografia , Animais , Teorema de Bayes , Quirópteros/microbiologia , Nariz/microbiologia , Filogenia , Filogeografia/métodos
2.
Conserv Biol ; 36(2): e13803, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34224186

RESUMO

White-nose syndrome (WNS) is a fungal disease that has caused precipitous declines in several North American bat species, creating an urgent need for conservation. We examined how microclimates and other characteristics of hibernacula have affected bat populations following WNS-associated declines and evaluated whether cooling of warm, little-used hibernacula could benefit bats. During the period following mass mortality (2013-2020), we conducted 191 winter surveys of 25 unmanipulated hibernacula and 6 manipulated hibernacula across Pennsylvania (USA). We joined these data with additional datasets on historical (pre-WNS) bat counts and on the spatial distribution of underground sites. We used generalized linear mixed models and model selection to identify factors affecting bat populations. Winter counts of Myotis lucifugus were higher and increased over time in colder hibernacula (those with midwinter temperatures of 3-6 °C) compared with warmer (7-11 °C) hibernacula. Counts of Eptesicus fuscus, Myotis leibii, and Myotis septentrionalis were likewise higher in colder hibernacula (temperature effects = -0.73 [SE 0.15], -0.51 [0.18], and -0.97 [0.28], respectively). Populations of M. lucifugus and M. septentrionalis increased most over time in hibernacula surrounded by more nearby sites, whereas Eptesicus fuscus counts remained high where they had been high before WNS onset (pre-WNS high count effect = 0.59 [0.22]). Winter counts of M. leibii were higher in hibernacula with high vapor pressure deficits (VPDs) (particularly over 0.1 kPa) compared with sites with lower VPDs (VPD effect = 15.3 [4.6]). Counts of M. lucifugus and E. fuscus also appeared higher where VPD was higher. In contrast, Perimyotis subflavus counts increased over time in relatively warm hibernacula and were unaffected by VPD. Where we manipulated hibernacula, we achieved cooling of on average 2.1 °C. At manipulated hibernacula, counts of M. lucifugus and P. subflavus increased over time (years since manipulation effect = 0.70 [0.28] and 0.51 [0.15], respectively). Further, there were more E. fuscus where cooling was greatest (temperature difference effect = -0.46 [SE 0.11]), and there was some evidence there were more P. subflavus in hibernacula sections that remained warm after manipulation. These data show bats are responding effectively to WNS through habitat selection. In M. lucifugus, M. septentrionalis, and possibly P. subflavus, this response is ongoing, with bats increasingly aggregating at suitable hibernacula, whereas E. fuscus remain in previously favored sites. Our results suggest that cooling warm sites receiving little use by bats is a viable strategy for combating WNS.


El síndrome de nariz blanca (SNB) es una enfermedad fúngica que ha causado declinaciones precipitadas en varias especies de murciélagos norteamericanos, creando una necesidad urgente por conservarlas. Analizamos cómo los microclimas y otras características de los hibernáculos han afectado a las poblaciones de murciélagos después de declinaciones asociadas al SNB y evaluamos si el enfriamiento de hibernáculos cálidos con poco uso podría beneficiar a los murciélagos. Durante el periodo posterior a una mortalidad masiva (2013 - 2020), realizamos 191 censos invernales en 25 hibernáculos sin manipulación y en seis hibernáculos manipulados localizados en Pensilvania (EUA). Juntamos estos datos con conjuntos adicionales de datos de los conteos históricos (previos WNS) de murciélagos y de la distribución espacial de sitios subterráneos. Usamos modelos mixtos lineales generalizados y selección de modelos para identificar los factores que afectan a las poblaciones de murciélagos. Los conteos invernales de Myotis lucifugus fueron más altos e incrementaron con el tiempo en los hibernáculos fríos (aquellos con temperaturas de 3 - 6° C registradas a mitad del invierno) en comparación con los hibernáculos cálidos (7 - 11° C). Los conteos Eptesicus fuscus, M. leibii, y M. septentrionalis fueron igualmente más altos en los hibernáculos fríos (efectos de la temperatura = -0.73 [ES 0.15], -0.51 [0.18], y -0.97 [0.28], respectivamente). Las poblaciones de M. lucifugus y M. septentrionalis fueron las que más incrementaron con el tiempo en los hibernáculos rodeados por más sitios cercanos, mientras que los conteos de E. fuscus permanecieron altos en donde ya habían sido altos antes del comienzo del SNB (el efecto del conteo alto previo al SNB = 0.59 [0.22]). Los conteos invernales de M. leibii fueron más altos en los hibernáculos con altos déficits de presión de vapor (DPV) (particularmente por encima de los 0.1 kPa) en comparación con los sitios con un DPV menor (efecto del VPD = 15.3 [4.6]). Los conteos de M. lucifugus y E. fuscus también fueron más altos en donde el DPV era alto. Al contrario, los conteos de Perimyotis subflavus incrementaron con el tiempo en hibernáculos relativamente cálidos y no se vieron afectados por el DPV. En donde alcanzamos un promedio de enfriamiento de 2.1° C de los hibernáculos, los conteos de M. lucifugus y P. subflavus incrementaron con el tiempo (años desde el efecto de manipulación = 0.70 [0.28] y 0.51 [0.15], respectivamente). Además, encontramos más E. fuscus en donde el enfriamiento fue mayor (efecto de la diferencia en temperatura = −0.46 [ES 0.11]), y hubo algunas evidencias de que había mayor cantidad de P. subflavus en las secciones del hibernáculo que permanecieron cálidas después de la manipulación. Estos datos muestran que los murciélagos están respondiendo efectivamente al SNB mediante la selección de hábitat. En el caso de M. lucifugus, M. septentrionalis y posiblemente P. subflavus, esta respuesta es persistente, con los murciélagos agrupándose cada vez más en hibernáculos adecuados, mientras que E. fuscus permanece en sitios favorecidos previamente. Nuestros resultados sugieren que el enfriamiento de los sitios cálidos que reciben poco uso por parte de los murciélagos es una estrategia viable para combatir al SNB. Enfriamiento de los Hibernáculos de Murciélagos para Mitigar el Síndrome de Nariz Blanca.


Assuntos
Ascomicetos , Quirópteros , Hibernação , Micoses , Animais , Quirópteros/microbiologia , Conservação dos Recursos Naturais , Micoses/prevenção & controle , Micoses/veterinária
3.
Conserv Biol ; 35(5): 1586-1597, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33877716

RESUMO

Assessing the scope and severity of threats is necessary for evaluating impacts on populations to inform conservation planning. Quantitative threat assessment often requires monitoring programs that provide reliable data over relevant spatial and temporal scales, yet such programs can be difficult to justify until there is an apparent stressor. Leveraging efforts of wildlife management agencies to record winter counts of hibernating bats, we collated data for 5 species from over 200 sites across 27 U.S. states and 2 Canadian provinces from 1995 to 2018 to determine the impact of white-nose syndrome (WNS), a deadly disease of hibernating bats. We estimated declines of winter counts of bat colonies at sites where the invasive fungus that causes WNS (Pseudogymnoascus destructans) had been detected to assess the threat impact of WNS. Three species undergoing species status assessment by the U.S. Fish and Wildlife Service (Myotis septentrionalis, Myotis lucifugus, and Perimyotis subflavus) declined by more than 90%, which warrants classifying the severity of the WNS threat as extreme based on criteria used by NatureServe. The scope of the WNS threat as defined by NatureServe criteria was large (36% of Myotis lucifugus range) to pervasive (79% of Myotis septentrionalis range) for these species. Declines for 2 other species (Myotis sodalis and Eptesicus fuscus) were less severe but still qualified as moderate to serious based on NatureServe criteria. Data-sharing across jurisdictions provided a comprehensive evaluation of scope and severity of the threat of WNS and indicated regional differences that can inform response efforts at international, national, and state or provincial jurisdictions. We assessed the threat impact of an emerging infectious disease by uniting monitoring efforts across jurisdictional boundaries and demonstrated the importance of coordinated monitoring programs, such as the North American Bat Monitoring Program (NABat), for data-driven conservation assessments and planning.


Alcance y Severidad del Síndrome de Nariz Blanca en los Murciélagos Hibernando en América del Norte Resumen La evaluación del alcance y la severidad de las amenazas es necesaria para los análisis de impacto sobre las poblaciones que se usan para orientar a la planeación de la conservación. La evaluación cuantitativa de amenazas con frecuencia requiere de programas de monitoreo que proporcionen datos confiables en escalas espaciales y temporales, aunque dichos programas pueden ser difíciles de justificar hasta que exista un estresante aparente. Gracias a una movilización de esfuerzos de las agencias de manejo de fauna para registrar los conteos invernales de murciélagos hibernadores, recopilamos datos para cinco especies en más de 200 sitios a lo largos de 27 estados de EUA y dos provincias canadienses entre 1995 y 2018 para determinar el impacto del síndrome de nariz blanca (SNB), una enfermedad mortal de los murciélagos hibernadores. Estimamos declinaciones en los conteos invernales de las colonias de murciélagos en sitios en donde el hongo invasivo que ocasiona el SNB (Pseudogymnoascus destructans) había sido detectado para evaluar el impacto de amenaza del SNB. Tres especies que se encuentran bajo valoración por parte del Servicio de Pesca y Vida Silvestre de los EUA (Myotis septentrionalis, Myotis lucifugus y Perimyotis subflavus) tuvieron una declinación de más del 90%, lo que justifica la clasificación de la severidad de la amenaza del SNB como extrema con base en el criterio usado por NatureServe. El alcance de la amenaza del SNB definido por el criterio de NatureServe fue desde amplio (36% de la distribución de Myotis lucifugus) hasta dominante (79% de la distribución de Myotis septentrionalis) para estas especies. Las declinaciones de otras dos especies (Myotis sodalis y Eptesicus fuscus) fueron menos severas, pero de igual manera quedaron clasificadas desde moderada hasta seria con base en los criterios de NatureServe. El intercambio de datos entre las jurisdicciones proporcionó una evaluación completa del alcance y la severidad de la amenaza del SNB e indicó las diferencias regionales que pueden guiar a los esfuerzos de respuesta realizados en las jurisdicciones internacionales, nacionales, estatales o provinciales. Evaluamos el impacto de amenaza de una enfermedad infecciosa emergente mediante la combinación de los esfuerzos de monitoreo que sobrepasan fronteras jurisdiccionales y demostramos la importancia que tienen para la planeación y la evaluación basadas en datos de la conservación los programas de monitoreo coordinados, como el Programa de Monitoreo de los Murciélagos Norteamericanos (NABat).


Assuntos
Quirópteros , Hibernação , Animais , Ascomicetos , Canadá , Conservação dos Recursos Naturais , América do Norte
4.
Oecologia ; 191(2): 295-309, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31506746

RESUMO

Resistance and tolerance allow organisms to cope with potentially life-threatening pathogens. Recently introduced pathogens initially induce resistance responses, but natural selection favors the development of tolerance, allowing for a commensal relationship to evolve. Mycosis by Pseudogymnoascus destructans, causing white-nose syndrome (WNS) in Nearctic hibernating bats, has resulted in population declines since 2006. The pathogen, which spread from Europe, has infected species of Palearctic Myotis for a longer period. We compared ecologically relevant responses to the fungal infection in the susceptible Nearctic M. lucifugus and less susceptible Palearctic M. myotis, to uncover factors contributing to survival differences in the two species. Samples were collected from euthermic bats during arousal from hibernation, a naturally occurring phenomenon, during which transcriptional responses are activated. We compared the whole-transcriptome responses in wild bats infected with P. destructans hibernating in their natural habitat. Our results show dramatically different local transcriptional responses to the pathogen between uninfected and infected samples from the two species. Whereas we found 1526 significantly upregulated or downregulated transcripts in infected M. lucifugus, only one transcript was downregulated in M. myotis. The upregulated response pathways in M. lucifugus include immune cell activation and migration, and inflammatory pathways, indicative of an unsuccessful attempt to resist the infection. In contrast, M. myotis appears to tolerate P. destructans infection by not activating a transcriptional response. These host-microbe interactions determine pathology, contributing to WNS susceptibility, or commensalism, promoting tolerance to fungal colonization during hibernation that favors survival.


Assuntos
Quirópteros , Hibernação , Micoses , Animais , Europa (Continente) , RNA
5.
PLoS Pathog ; 12(12): e1006076, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28027325

RESUMO

White-nose syndrome is one of the most lethal wildlife diseases, killing over 5 million North American bats since it was first reported in 2006. The causal agent of the disease is a psychrophilic filamentous fungus, Pseudogymnoascus destructans. The fungus is widely distributed in North America and Europe and has recently been found in some parts of Asia, but interestingly, no mass mortality is observed in European or Asian bats. Here we report a novel double-stranded RNA virus found in North American isolates of the fungus and show that the virus can be used as a tool to study the epidemiology of White-nose syndrome. The virus, termed Pseudogymnoascus destructans partitivirus-pa, contains 2 genomic segments, dsRNA 1 and dsRNA 2 of 1.76 kbp and 1.59 kbp respectively, each possessing a single open reading frame, and forms isometric particles approximately 30 nm in diameter, characteristic of the genus Gammapartitivirus in the family Partitiviridae. Phylogenetic analysis revealed that the virus is closely related to Penicillium stoloniferum virus S. We were able to cure P. destructans of the virus by treating fungal cultures with polyethylene glycol. Examination of 62 isolates of P. destructans including 35 from United States, 10 from Canada and 17 from Europe showed virus infection only in North American isolates of the fungus. Bayesian phylogenetic analysis using nucleotide sequences of the viral coat protein geographically clustered North American isolates indicating fungal spread followed by local adaptation of P. destructans in different regions of the United States and Canada. This is the first demonstration that a mycovirus potentially can be used to study fungal disease epidemiology.


Assuntos
Quirópteros/virologia , Micovírus/genética , Micoses/veterinária , Vírus de RNA/genética , Animais , Teorema de Bayes , Northern Blotting , Filogenia , Reação em Cadeia da Polimerase , Síndrome
6.
Mol Ecol ; 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30080945

RESUMO

Hibernation, the use of prolonged torpor to depress metabolism, is employed by mammals to conserve resources during extended periods of extreme temperatures and/or resource limitation. Mammalian hibernators arouse to euthermy periodically during torpor for reasons that are not well understood, and these arousals may facilitate immune processes. To determine whether arousals enable host responses to pathogens, we used dual RNA-Seq and a paired sampling approach to examine gene expression in a hibernating bat, the little brown myotis (Myotis lucifugus). During torpor, transcript levels differed in only a few genes between uninfected wing tissue and adjacent tissue infected with Pseudogymnoascus destructans, the fungal pathogen that causes white-nose syndrome. Within 70-80 min after emergence from torpor, large changes in gene expression were observed due to local infection, particularly in genes involved in pro-inflammatory host responses to fungal pathogens, but also in many genes involved in immune responses and metabolism. These results support the hypothesis that torpor is a period of relative immune dormancy and arousals allow for local immune responses in infected tissues during hibernation. Host-pathogen interactions were also found to regulate gene expression in the pathogen differently depending on the torpor state of the host. Hibernating species must balance the benefits of energy and water conservation achieved during torpor with the costs of decreased immune competence. Interbout arousals allow hibernators to optimize these, and other, trade-offs during prolonged hibernation by enabling host responses to pathogens within brief, periodic episodes of euthermy.

8.
Ecol Evol ; 14(6): e11523, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38932974

RESUMO

Emerging infectious diseases threaten wildlife globally. While the effects of infectious diseases on hosts with severe infections and high mortality rates often receive considerable attention, effects on hosts that persist despite infection are less frequently studied. To understand how persisting host populations change in the face of disease, we quantified changes to the capture rates of Eptesicus fuscus (big brown bats), a persisting species susceptible to infection by the invasive fungal pathogen Pseudogymnoascus destructans (Pd; causative agent for white-nose syndrome), across the eastern US using a 30-year dataset. Capture rates of male and female E. fuscus increased from preinvasion to pathogen establishment years, with greater increases to the capture rates of females than males. Among females, capture rates of pregnant and post-lactating females increased by pathogen establishment. We outline potential mechanisms for these broad demographic changes in E. fuscus capture rates (i.e., increases to foraging from energy deficits created by Pd infection, increases to relative abundance, or changes to reproductive cycles), and suggest future research for identifying mechanisms for increasing capture rates across the eastern US. These data highlight the importance of understanding how populations of persisting host species change following pathogen invasion across a broad spatial scale. Understanding changes to population composition following pathogen invasion can identify broad ecological patterns across space and time, and open new avenues for research to identify drivers of those patterns.

9.
ANZ J Surg ; 94(5): 938-944, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38131396

RESUMO

BACKGROUND: Acute surgical units (ASU) are increasingly being adopted and in our system are staffed by colorectal and non-colorectal general surgeons. This study aims to evaluate whether surgeon specialization was associated with improved outcomes in perianal abscess. METHODS: Patients with perianal abscess admitted to the ASU between 2016 and 2020 were identified from a prospective database and their medical records reviewed. Patients with IBD, treatment for fistula-in-ano within the preceding year, or perianal sepsis of non-cryptoglandular origin were excluded. Patients admitted under an ASU colorectal (CR) consultant were compared with those under a non-CR general surgeon in a retrospective cohort study. Primary outcome was perianal abscess recurrence. For those without initial fistula, hazard of recurrent abscess or fistula was analysed. Multivariable Cox PH regression analysis was performed. RESULTS: Four-hundred and eight patients were included (150 CR, 258 non-CR). The CR group more frequently had a fistula identified at index operation (34.0% versus 10.9%, P < 0.0001). However, Cox multivariable analysis found no difference in hazard of recurrent abscess between groups (HR 1.12, 95% CI 0.65-1.95, P = 0.681)). Abscess recurred in 18.7% CR and 15.5% non-CR. Subsequent fistula developed in 14.7% in both groups. For patients without initial fistula, there was no difference between groups in hazard of recurrent abscess or fistula (HR 1.18, 95% CI 0.69-2.01, P = 0.539). CONCLUSION: Surgeon specialization was not associated with improved outcomes for ASU patients with perianal abscess, albeit with potential selection bias. CR surgeons were more proactive identifying fistulas; this raises the possibility that drainage alone may be adequate treatment.


Assuntos
Abscesso , Doenças do Ânus , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Abscesso/cirurgia , Adulto , Doenças do Ânus/cirurgia , Recidiva , Resultado do Tratamento , Fístula Retal/cirurgia , Cirurgiões , Doença Aguda , Especialização , Idoso
10.
bioRxiv ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38559042

RESUMO

The MYC proto-oncogenes (c-MYC, MYCN , MYCL ) are among the most deregulated oncogenic drivers in human malignancies including high-risk neuroblastoma, 50% of which are MYCN -amplified. Genetically engineered mouse models (GEMMs) based on the MYCN transgene have greatly expanded the understanding of neuroblastoma biology and are powerful tools for testing new therapies. However, a lack of c-MYC-driven GEMMs has hampered the ability to better understand mechanisms of neuroblastoma oncogenesis and therapy development given that c-MYC is also an important driver of many high-risk neuroblastomas. In this study, we report two transgenic murine neuroendocrine models driven by conditional c-MYC induction in tyrosine hydroxylase (Th) and dopamine ß-hydroxylase (Dbh)-expressing cells. c-MYC induction in Th-expressing cells leads to a preponderance of Pdx1 + somatostatinomas, a type of pancreatic neuroendocrine tumor (PNET), resembling human somatostatinoma with highly expressed gene signatures of δ cells and potassium channels. In contrast, c-MYC induction in Dbh-expressing cells leads to onset of neuroblastomas, showing a better transforming capacity than MYCN in a comparable C57BL/6 genetic background. The c-MYC murine neuroblastoma tumors recapitulate the pathologic and genetic features of human neuroblastoma, express GD2, and respond to anti-GD2 immunotherapy. This model also responds to DFMO, an FDA-approved inhibitor targeting ODC1, which is a known MYC transcriptional target. Thus, establishing c-MYC-overexpressing GEMMs resulted in different but related tumor types depending on the targeted cell and provide useful tools for testing immunotherapies and targeted therapies for these diseases.

11.
bioRxiv ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38585889

RESUMO

The cellular plasticity of neuroblastoma is defined by a mixture of two major cell states, adrenergic (ADRN) and mesenchymal (MES), which may contribute to therapy resistance. However, how neuroblastoma cells switch cellular states during therapy remains largely unknown and how to eradicate neuroblastoma regardless of their cell states is a clinical challenge. To better understand the lineage switch of neuroblastoma in chemoresistance, we comprehensively defined the transcriptomic and epigenetic map of ADRN and MES types of neuroblastomas using human and murine models treated with indisulam, a selective RBM39 degrader. We showed that cancer cells not only undergo a bidirectional switch between ADRN and MES states, but also acquire additional cellular states, reminiscent of the developmental pliancy of neural crest cells. The lineage alterations are coupled with epigenetic reprogramming and dependency switch of lineage-specific transcription factors, epigenetic modifiers and targetable kinases. Through targeting RNA splicing, indisulam induces an inflammatory tumor microenvironment and enhances anticancer activity of natural killer cells. The combination of indisulam with anti-GD2 immunotherapy results in a durable, complete response in high-risk transgenic neuroblastoma models, providing an innovative, rational therapeutic approach to eradicate tumor cells regardless of their potential to switch cell states.

12.
Magn Reson Imaging ; 101: 57-66, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37028608

RESUMO

Alzheimer's disease (AD) has been associated with amyloid and tau pathology, as well as neurodegeneration. Beyond these hallmark features, white matter microstructural abnormalities have been observed using MRI. The objective of this study was to assess grey matter atrophy and white matter microstructural changes in a preclinical mouse model of AD (3xTg-AD) using voxel-based morphometry (VBM) and free-water (FW) diffusion tensor imaging (FW-DTI). Compared to controls, lower grey matter density was observed in the 3xTg-AD model, corresponding to the small clusters in the caudate-putamen, hypothalamus, and cortex. DTI-based fractional anisotropy (FA) was decreased in the 3xTg model, while the FW index was increased. Notably, the largest clusters for both FW-FA and FW index were in the fimbria, with other regions including the anterior commissure, corpus callosum, forebrain septum, and internal capsule. Additionally, the presence of amyloid and tau in the 3xTg model was confirmed with histopathology, with significantly higher levels observed across many regions of the brain. Taken together, these results are consistent with subtle neurodegenerative and white matter microstructural changes in the 3xTg-AD model that manifest as increased FW, decreased FW-FA, and decreased grey matter density.


Assuntos
Doença de Alzheimer , Substância Branca , Camundongos , Animais , Doença de Alzheimer/patologia , Substância Cinzenta/patologia , Imagem de Tensor de Difusão/métodos , Substância Branca/patologia , Encéfalo/patologia , Atrofia/patologia
13.
Data Brief ; 49: 109353, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37600136

RESUMO

Emerging infectious diseases threaten wildlife populations. Without well monitored wildlife systems, it is challenging to determine accurate population and ecosystem losses following disease emergence. North American temperate bats present a unique opportunity for studying the broad impacts of wildlife disease emergence, as their federal monitoring programs were prioritized in the USA throughout the 20th century and they are currently threatened by the invasive fungal pathogen, Pseudogymnoascus destructans (Pd), which causes white-nose syndrome. Here we provide a long-term dataset for capture records of Eptesicus fuscus (big brown bat) across the eastern USA, spanning 16 years before and 14 years after Pd invasion into North America. These data represent 30,496 E. fuscus captures across 3,567 unique sites. We encourage the use of this dataset for quantifying impacts of wildlife disease and other threats to wildlife (e.g., climate change) with the incorporation of other available data. We welcome additional data contributions for E. fuscus captures across North and Central America as well as the inclusion of other variables into the dataset that contribute to the quantification of wildlife health.

14.
Viruses ; 15(5)2023 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-37243189

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), believed to have originated from a bat species, can infect a wide range of non-human hosts. Bats are known to harbor hundreds of coronaviruses capable of spillover into human populations. Recent studies have shown a significant variation in the susceptibility among bat species to SARS-CoV-2 infection. We show that little brown bats (LBB) express angiotensin-converting enzyme 2 receptor and the transmembrane serine protease 2, which are accessible to and support SARS-CoV-2 binding. All-atom molecular dynamics (MD) simulations revealed that LBB ACE2 formed strong electrostatic interactions with the RBD similar to human and cat ACE2 proteins. In summary, LBBs, a widely distributed North American bat species, could be at risk of SARS-CoV-2 infection and potentially serve as a natural reservoir. Finally, our framework, combining in vitro and in silico methods, is a useful tool to assess the SARS-CoV-2 susceptibility of bats and other animal species.


Assuntos
COVID-19 , Quirópteros , Animais , Humanos , SARS-CoV-2/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo
15.
PLoS One ; 17(7): e0270478, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35776732

RESUMO

The decline in northern myotis (Myotis septentrionalis) populations due to the disease white-nose syndrome (WNS) has led to the species receiving federal protection in the United States and Canada, requiring conservation of critical habitats. However, considerably more is known about summer habitat preferences of northern myotis compared to late summer through winter. Our goal was to describe the seasonal presence and habitat use of a remnant colony of northern myotis in central Pennsylvania. We radio-tagged 31 northern myotis and established 6 acoustic monitoring stations to document activity from 2017-2021. We found that roost trees used during the maternity season by reproductive females were occupied by bats during both summer (21 June-14 August) and autumn (15 August-31 October), indicating similar habitat use patterns between seasons. During this time, both males and females preferred to roost in dead and declining trees. No other variable influenced male use, but females also preferred trees located close to water and in forest stands with higher basal area than randomly located trees. Northern myotis with active transmitters never left the study area and were tracked to roosts until early November. During October and November, a female and male were tracked to an underground network of air-filled voids (the Milieu Souterrain Superficiel) we presume to be a hibernaculum. Northern myotis calls were recorded outside this roost between March and October, and bats were observed emerging from this roost during spring and autumn but not summer. Acoustic activity at this site exhibited a seasonal pattern that differed from acoustic activity near roost trees and foraging areas, with a peak of activity during late summer when northern myotis are known to swarm. These data show that northern myotis maternity roosts are used extensively outside of summer and may be vulnerable to forestry practices that occur even outside of the pup-rearing season. These data also support the growing evidence that some northern myotis hibernate outside of caves and mines.


Assuntos
Quirópteros , Animais , Ecossistema , Feminino , Humanos , Masculino , Pennsylvania , Gravidez , Estações do Ano , Árvores
16.
Virology ; 571: 1-11, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35421704

RESUMO

Bats have recently been identified as potential reservoir hosts for mammalian orthoreoviruses (MRVs) throughout Europe and China. Here we present the first evolutionary and biological characterization of bat-borne MRVs in North America, including phylogenomic analysis, in vitro relative infectivity in bat and other mammalian cell cultures, host cell receptor specificity, and epifluorescence microscopy of viral factory formation. Through genetic and phylogenetic comparisons, we show that two divergent MRV serotype 2 (T2) strains - isolated from a silver-haired bat (Lasionycteris noctivagans) and a big brown bat (Eptesicus fuscus) from Pennsylvania, USA - provide an evolutionary link to an MRV strain (T2W) recovered from an 8-week-old infant who died in Winnipeg, Manitoba, Canada in 1997. Although these findings suggest North American bats may represent a previously unrecognized source for the cross-species transmission of MRVs to other animals, including humans, the ecology and epidemiology of MRVs in wildlife remain enigmatic.


Assuntos
Quirópteros , Orthoreovirus de Mamíferos , Animais , Animais Selvagens , Especificidade de Hospedeiro , Humanos , Orthoreovirus de Mamíferos/genética , Filogenia
17.
JAMA Surg ; 157(1): 34-41, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34668964

RESUMO

Importance: There are discrepancies in guidelines on preparation for colorectal surgery. While intravenous (IV) antibiotics are usually administered, the use of mechanical bowel preparation (MBP), enemas, and/or oral antibiotics (OA) is controversial. Objective: To summarize all data from randomized clinical trials (RCTs) that met selection criteria using network meta-analysis (NMA) to determine the ranking of different bowel preparation treatment strategies for their associations with postoperative outcomes. Data Sources: Data sources included MEDLINE, Embase, Cochrane, and Scopus databases with no language constraints, including abstracts and articles published prior to 2021. Study Selection: Randomized studies of adults undergoing elective colorectal surgery with appropriate aerobic and anaerobic antibiotic cover that reported on incisional surgical site infection (SSI) or anastomotic leak were selected for inclusion in the analysis. These were selected by multiple reviewers and adjudicated by a separate lead investigator. A total of 167 of 6833 screened studies met initial selection criteria. Data Extraction and Synthesis: NMA was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Data were extracted by multiple independent observers and pooled in a random-effects model. Main Outcomes and Measures: Primary outcomes were incisional SSI and anastomotic leak. Secondary outcomes included other infections, mortality, ileus, and adverse effects of preparation. Results: A total of 35 RCTs that included 8377 patients were identified. Treatments compared IV antibiotics (2762 patients [33%]), IV antibiotics with enema (222 patients [3%]), IV antibiotics with OA with or without enema (628 patients [7%]), MBP with IV antibiotics (2712 patients [32%]), MBP with IV antibiotics with OA (with good IV antibiotic cover in 925 patients [11%] and with good overall antibiotic cover in 375 patients [4%]), MBP with OA (267 patients [3%]), and OA (486 patients [6%]). The likelihood of incisional SSI was significantly lower for those receiving IV antibiotics with OA with or without enema (rank 1) and MBP with adequate IV antibiotics with OA (rank 2) compared with all other treatment options. The addition of OA to IV antibiotics, both with and without MBP, was associated with a reduction in incisional SSI by greater than 50%. There were minimal differences between treatments in anastomotic leak and in any of the secondary outcomes. Conclusions and Relevance: This NMA demonstrated that the addition of OA to IV antibiotics were associated with a reduction in incisional SSI by greater than 50%. The results support the addition of OA to IV antibiotics to reduce incisional SSI among patients undergoing elective colorectal surgery.


Assuntos
Cirurgia Colorretal , Administração Oral , Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Procedimentos Cirúrgicos Eletivos , Humanos , Metanálise em Rede , Cuidados Pré-Operatórios , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/prevenção & controle
18.
BMC Ecol Evol ; 22(1): 137, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36418951

RESUMO

BACKGROUND: Allegheny woodrats (Neotoma magister) are found in metapopulations distributed throughout the Interior Highlands and Appalachia. Historically these metapopulations persisted as relatively fluid networks, enabling gene flow between subpopulations and recolonization of formerly extirpated regions. However, over the past 45 years, the abundance of Allegheny woodrats has declined throughout the species' range due to a combination of habitat destruction, declining hard mast availability, and roundworm parasitism. In an effort to initiate genetic rescue of a small, genetically depauperate subpopulation in New Jersey, woodrats were translocated from a genetically robust population in Pennsylvania (PA) in 2015, 2016 and 2017. Herein, we assess the efficacy of these translocations to restore genetic diversity within the recipient population. RESULTS: We designed a novel 134 single nucleotide polymorphism panel, which was used to genotype the six woodrats translocated from PA and 82 individuals from the NJ population captured before and after the translocation events. These data indicated that a minimum of two translocated individuals successfully produced at least 13 offspring, who reproduced as well. Further, population-wide observed heterozygosity rose substantially following the first set of translocations, reached levels comparable to that of populations in Indiana and Ohio, and remained elevated over the subsequent years. Abundance also increased during the monitoring period, suggesting Pennsylvania translocations initiated genetic rescue of the New Jersey population. CONCLUSIONS: Our results indicate, encouragingly, that very small numbers of translocated individuals can successfully restore the genetic diversity of a threatened population. Our work also highlights the challenges of managing very small populations, such as when translocated individuals have greater reproductive success relative to residents. Finally, we note that ongoing work with Allegheny woodrats may broadly shape our understanding of genetic rescue within metapopulations and across heterogeneous landscapes.


Assuntos
Polimorfismo de Nucleotídeo Único , Sigmodontinae , Humanos , Animais , Polimorfismo de Nucleotídeo Único/genética , Sigmodontinae/genética , Fluxo Gênico , Ecossistema , Dinâmica Populacional
19.
Transl Stroke Res ; 13(5): 816-829, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35258803

RESUMO

Vascular contributions to cognitive impairment and dementia (VCID) secondary to chronic mild-moderate cerebral ischemia underlie a significant percentage of cases of dementia. We previously reported that either genetic deficiency of the complement C3a receptor (C3aR) or its pharmacological inhibition protects against cerebral ischemia in rodents, while others have implicated C3aR in the pathogenesis seen in rodent transgenic models of Alzheimer's disease. In the present study, we evaluated the role of complement C3a-C3aR signaling in the onset and progression of VCID. We utilized the bilateral common carotid artery stenosis (BCAS) model to induce VCID in male C57BL/6 wild-type and C3aR-knockout (C3aR-/-) mice. Cerebral blood flow (CBF) changes, hippocampal atrophy (HA), white matter degeneration (WMD), and ventricular size were assessed at 4 months post-BCAS using laser speckle contrast analysis (LSCI) and magnetic resonance imaging (MRI). Cognitive function was evaluated using the Morris water maze (MWM), and novel object recognition (NOR), immunostaining, and western blot were performed to assess the effect of genetic C3aR deletion on post-VCID outcomes. BCAS resulted in decreased CBF and increased HA, WMD, and neurovascular inflammation in WT (C57BL/6) compared to C3aR-/- (C3aR-KO) mice. Moreover, C3aR-/- mice exhibited improved cognitive function on NOR and MWM relative to WT controls. We conclude that over-activation of the C3a/C3aR axis exacerbates neurovascular inflammation leading to poor VCID outcomes which are mitigated by C3aR deletion. Future studies are warranted to dissect the role of cell-specific C3aR in VCID.


Assuntos
Isquemia Encefálica , Disfunção Cognitiva , Demência Vascular , Receptores de Complemento , Animais , Isquemia Encefálica/complicações , Disfunção Cognitiva/patologia , Demência Vascular/complicações , Modelos Animais de Doenças , Hipocampo/patologia , Inflamação/complicações , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Complemento/genética
20.
J Neurotrauma ; 39(19-20): 1429-1441, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35593008

RESUMO

Severe traumatic brain injury (TBI) results in cognitive dysfunction in part due to vascular perturbations. In contrast, the long-term vasculo-cognitive pathophysiology of mild TBI (mTBI) remains unknown. We evaluated mTBI effects on chronic cognitive and cerebrovascular function and assessed their interrelationships. Sprague-Dawley rats received midline fluid percussion injury (n = 20) or sham (n = 21). Cognitive function was assessed (3- and 6-month novel object recognition [NOR], novel object location [NOL], and temporal order object recognition [TOR]). Six-month cerebral blood flow (CBF) and cerebral blood volume (CBV) using contrast magnetic resonance imaging (MRI) and ex vivo circle of Willis artery endothelial and smooth muscle-dependent function were measured. mTBI rats showed significantly impaired NOR, with similar trends (non-significant) in NOL/TOR. Regional CBF and CBV were similar in sham and mTBI. NOR correlated with CBF in lateral hippocampus, medial hippocampus, and primary somatosensory barrel cortex, whereas it inversely correlated with arterial smooth muscle-dependent dilation. Six-month baseline endothelial and smooth muscle-dependent arterial function were similar among mTBI and sham, but post-angiotensin 2 stimulation, mTBI showed no change in smooth muscle-dependent dilation from baseline response, unlike the reduction in sham. mTBI led to chronic cognitive dysfunction and altered angiotensin 2-stimulated smooth muscle-dependent vasoreactivity. The findings of persistent pathophysiological consequences of mTBI in this animal model add to the broader understanding of chronic pathophysiological sequelae in human mild TBI.


Assuntos
Concussão Encefálica , Circulação Cerebrovascular , Cognição , Animais , Humanos , Ratos , Angiotensinas , Concussão Encefálica/complicações , Concussão Encefálica/patologia , Ratos Sprague-Dawley
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