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1.
J Biol Chem ; 299(5): 104707, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37061001

RESUMO

Virus entry into animal cells is initiated by attachment to target macromolecules located on host cells. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) trimeric spike glycoprotein targets host angiotensin converting enzyme 2 to gain cellular access. The SARS-CoV-2 glycoprotein contains a neurotoxin-like region that has sequence similarities to the rabies virus and the HIV glycoproteins, as well as to snake neurotoxins, which interact with nicotinic acetylcholine receptor (nAChR) subtypes via this region. Using a peptide of the neurotoxin-like region of SARS-CoV-2 (SARS-CoV-2 glycoprotein peptide [SCoV2P]), we identified that this area moderately inhibits α3ß2, α3ß4, and α4ß2 subtypes, while potentiating and inhibiting α7 nAChRs. These nAChR subtypes are found in target tissues including the nose, lung, central nervous system, and immune cells. Importantly, SCoV2P potentiates and inhibits ACh-induced α7 nAChR responses by an allosteric mechanism, with nicotine enhancing these effects. Live-cell confocal microscopy was used to confirm that SCoV2P interacts with α7 nAChRs in transfected neuronal-like N2a and human embryonic kidney 293 cells. The SARS-CoV-2 ectodomain functionally potentiates and inhibits the α7 subtype with nanomolar potency. Our functional findings identify that the α7 nAChR is a target for the SARS-CoV-2 glycoprotein, providing a new aspect to our understanding of SARS-CoV-2 and host cell interactions, in addition to disease pathogenesis.


Assuntos
Receptores Nicotínicos , SARS-CoV-2 , Receptor Nicotínico de Acetilcolina alfa7 , Humanos , Receptor Nicotínico de Acetilcolina alfa7/genética , COVID-19 , Neurotoxinas , Receptores Nicotínicos/genética , Glicoproteína da Espícula de Coronavírus/genética
2.
Cell ; 137(2): 283-94, 2009 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-19379694

RESUMO

Many bacterial pathogens and symbionts utilize type III secretion systems to deliver bacterial effector proteins into host cells. These effector proteins have the capacity to modulate a large variety of cellular functions in a highly regulated manner. Here, we report that the phosphoinositide phosphatase SopB, a Salmonella Typhimurium type III secreted effector protein, diversifies its function by localizing to different cellular compartments in a ubiquitin-dependent manner. We show that SopB utilizes the same enzymatic activity to modulate actin-mediated bacterial internalization and Akt activation at the plasma membrane and vesicular trafficking and intracellular bacterial replication at the phagosome. Thus, by exploiting the host cellular machinery, Salmonella Typhimurium has evolved the capacity to broaden the functional repertoire of a virulence factor to maximize its ability to modulate cellular functions.


Assuntos
Proteínas de Bactérias/metabolismo , Ubiquitina/metabolismo , Actinas/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Pinocitose , Proteínas Proto-Oncogênicas c-akt/metabolismo , Infecções por Salmonella/microbiologia , Salmonella typhimurium/metabolismo , Salmonella typhimurium/patogenicidade
3.
Innov High Educ ; 44(2): 119-131, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31592203

RESUMO

As a pilot intervention strategy to support undergraduate students, especially rural and Alaska Native students who are pursuing biomedical science research and career trajectories, we have developed a unique, mid-level Research, Advising, and Mentoring Professional (RAMP) position. In this article we outline the reasons for creating this position, RAMP qualifications, training, duties, and differences between RAMP and other positions typically found in higher education. Additionally, we discuss the evolution of the position and why it may be of interest to other institutions as they address similar issues involving students from underrepresented groups. Preliminary survey and focus group data from students mentored directly by RAMPs indicated that the holistic advising approach of RAMPs has had a positive impact on student experiences by supporting persistence in degree programs and providing psychosocial support of both personal and professional development.

4.
Int J Syst Evol Microbiol ; 67(5): 1115-1119, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28056218

RESUMO

During the summers of 2013 and 2014, isolates of a novel Gram-stain-negative coccus in the genus Neisseriawere obtained from the contents of nonviable greater white-fronted goose (Anseralbifrons) eggs on the Arctic Coastal Plain of Alaska. We used a polyphasic approach to determine whether these isolates represent a novel species. 16S rRNA gene sequences, 23S rRNA gene sequences, and chaperonin 60 gene sequences suggested that these Alaskan isolates are members of a distinct species that is most closely related to Neisseria canis, Neisseriaanimaloris and Neisseriashayeganii. Analysis of the rplF gene additionally showed that the isolates are unique and most closely related to Neisseriaweaveri. Average nucleotide identity of the whole genome sequence of the type strain was between 71.5 and 74.6 % compared to close relatives, further supporting designation as a novel species. Fatty acid methyl ester analysis showed a predominance of C14 : 0, C16 : 0 and C16 : 1ω7c fatty acids. Finally, biochemical characteristics distinguished the isolates from other species of the genus Neisseria. On the basis of these combined data, the isolates are proposed to represent a novel species of the genus Neisseria, with the name Neisseria arctica sp. nov. The type strain is KH1503T (=ATCC TSD-57T=DSM 103136T).


Assuntos
Gansos/microbiologia , Neisseria/classificação , Óvulo/microbiologia , Filogenia , Alaska , Animais , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , Chaperonina 60/genética , DNA Bacteriano/genética , Ácidos Graxos/química , Neisseria/genética , Neisseria/isolamento & purificação , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Análise de Sequência de DNA
5.
Mol Ecol ; 25(3): 675-88, 2016 02.
Artigo em Inglês | MEDLINE | ID: mdl-26661691

RESUMO

For pathogens that infect multiple species, the distinction between reservoir hosts and spillover hosts is often difficult. In Alaska, three variants of the arctic rabies virus exist with distinct spatial distributions. We tested the hypothesis that rabies virus variant distribution corresponds to the population structure of the primary rabies hosts in Alaska, arctic foxes (Vulpes lagopus) and red foxes (Vulpes vulpes) to possibly distinguish reservoir and spillover hosts. We used mitochondrial DNA (mtDNA) sequence and nine microsatellites to assess population structure in those two species. mtDNA structure did not correspond to rabies virus variant structure in either species. Microsatellite analyses gave varying results. Bayesian clustering found two groups of arctic foxes in the coastal tundra region, but for red foxes it identified tundra and boreal types. Spatial Bayesian clustering and spatial principal components analysis identified 3 and 4 groups of arctic foxes, respectively, closely matching the distribution of rabies virus variants in the state. Red foxes, conversely, showed eight clusters comprising two regions (boreal and tundra) with much admixture. These results run contrary to previous beliefs that arctic fox show no fine-scale spatial population structure. While we cannot rule out that the red fox is part of the maintenance host community for rabies in Alaska, the distribution of virus variants appears to be driven primarily by the arctic fox. Therefore, we show that host population genetics can be utilized to distinguish between maintenance and spillover hosts when used in conjunction with other approaches.


Assuntos
Raposas/genética , Genética Populacional , Vírus da Raiva/classificação , Raiva/veterinária , Alaska , Animais , Teorema de Bayes , Análise por Conglomerados , DNA Mitocondrial/genética , Raposas/classificação , Raposas/virologia , Haplótipos , Repetições de Microssatélites , Dados de Sequência Molecular , Filogenia , Raiva/epidemiologia , Vírus da Raiva/isolamento & purificação
6.
Appl Environ Microbiol ; 81(16): 5583-92, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26048928

RESUMO

To address the role of bacterial infection in hatching failure of wild geese, we monitored embryo development in a breeding population of Greater white-fronted geese (Anser albifrons) on the Arctic Coastal Plain of Alaska. During 2013, we observed mortality of normally developing embryos and collected 36 addled eggs for analysis. We also collected 17 infertile eggs for comparison. Using standard culture methods and gene sequencing to identify bacteria within collected eggs, we identified a potentially novel species of Neisseria in 33 eggs, Macrococcus caseolyticus in 6 eggs, and Streptococcus uberis and Rothia nasimurium in 4 eggs each. We detected seven other bacterial species at lower frequencies. Sequences of the 16S rRNA genes from the Neisseria isolates most closely matched sequences from N. animaloris and N. canis (96 to 97% identity), but phylogenetic analysis suggested substantial genetic differentiation between egg isolates and known Neisseria species. Although definitive sources of the bacteria remain unknown, we detected Neisseria DNA from swabs of eggshells, nest contents, and cloacae of nesting females. To assess the pathogenicity of bacteria identified in contents of addled eggs, we inoculated isolates of Neisseria, Macrococcus, Streptococcus, and Rothia at various concentrations into developing chicken eggs. Seven-day mortality rates varied from 70 to 100%, depending on the bacterial species and inoculation dose. Our results suggest that bacterial infections are a source of embryo mortality in wild geese in the Arctic.


Assuntos
Bactérias/classificação , Infecções Bacterianas/veterinária , Doenças das Aves/mortalidade , Perda do Embrião/etiologia , Alaska , Animais , Regiões Árticas , Bactérias/genética , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Infecções Bacterianas/mortalidade , Técnicas Bacteriológicas , Doenças das Aves/microbiologia , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Embrião não Mamífero , Gansos , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Int J Circumpolar Health ; 83(1): 2318059, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38369781

RESUMO

Rabies is often described as the quintessential One Health problem, linking especially animal health to human health. I examined how rabies is managed in the circumpolar North through semi-structured interviews of key informants in three cases: Alaska, Northwest Territories, and Svalbard. While rabies is controlled at the territorial or state level in the Northwest Territories and Alaska, respectively, the perception of where authority lies in rabies management is less evident in Norway concerning Svalbard than in the other two cases. Respondents generally characterised the working relationship between sectors and scales of governments as positive. However, coordination remains one of the main challenges to rabies management, with harsh environmental conditions and small remote communities adding additional challenges in all three cases. Rabies managers in Svalbard also face unique conditions, such as risks associated with hunting and the particular administrative structure of Svalbard. Due to limited veterinary services in dispersed small and remote communities, dogs present challenges to rabies management in Alaska and the Northwest Territories. Personal relationships are important in disease management across agencies, and the unique challenges in the far North will likely pose challenges in adopting approaches to disease management from temperate climates.


Assuntos
Saúde Única , Vírus da Raiva , Raiva , Animais , Humanos , Cães , Raiva/prevenção & controle , Alaska , Noruega
8.
Front Cell Infect Microbiol ; 14: 1394713, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836054

RESUMO

The rabies virus enters the nervous system by interacting with several molecular targets on host cells to modify behavior and trigger receptor-mediated endocytosis of the virion by poorly understood mechanisms. The rabies virus glycoprotein (RVG) interacts with the muscle acetylcholine receptor and the neuronal α4ß2 subtype of the nicotinic acetylcholine receptor (nAChR) family by the putative neurotoxin-like motif. Given that the neurotoxin-like motif is highly homologous to the α7 nAChR subtype selective snake toxin α-bungarotoxin (αBTX), other nAChR subtypes are likely involved. The purpose of this study is to determine the activity of the RVG neurotoxin-like motif on nAChR subtypes that are expressed in brain regions involved in rabid animal behavior. nAChRs were expressed in Xenopus laevis oocytes, and two-electrode voltage clamp electrophysiology was used to collect concentration-response data to measure the functional effects. The RVG peptide preferentially and completely inhibits α7 nAChR ACh-induced currents by a competitive antagonist mechanism. Tested heteromeric nAChRs are also inhibited, but to a lesser extent than the α7 subtype. Residues of the RVG peptide with high sequence homology to αBTX and other neurotoxins were substituted with alanine. Altered RVG neurotoxin-like peptides showed that residues phenylalanine 192, arginine 196, and arginine 199 are important determinants of RVG peptide apparent potency on α7 nAChRs, while serine 195 is not. The evaluation of the rabies ectodomain reaffirmed the observations made with the RVG peptide, illustrating a significant inhibitory impact on α7 nAChR with potency in the nanomolar range. In a mammalian cell culture model of neurons, we confirm that the RVG peptide binds preferentially to cells expressing the α7 nAChR. Defining the activity of the RVG peptide on nAChRs expands our understanding of basic mechanisms in host-pathogen interactions that result in neurological disorders.


Assuntos
Glicoproteínas , Vírus da Raiva , Xenopus laevis , Receptor Nicotínico de Acetilcolina alfa7 , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Vírus da Raiva/fisiologia , Vírus da Raiva/metabolismo , Humanos , Glicoproteínas/metabolismo , Glicoproteínas/genética , Oócitos/metabolismo , Proteínas Virais/metabolismo , Proteínas Virais/genética , Proteínas do Envelope Viral/metabolismo , Proteínas do Envelope Viral/genética , Interações Hospedeiro-Patógeno , Ligação Proteica , Raiva/metabolismo , Raiva/virologia , Acetilcolina/metabolismo , Acetilcolina/farmacologia , Neurotoxinas/metabolismo , Neurotoxinas/farmacologia
9.
Heliyon ; 8(9): e10434, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36091963

RESUMO

Rabies causes approximately 60,000 casualties annually and has a case fatality rate approaching 100% once clinical signs occur. The glycoprotein on the surface of the virion is important for the host immune response and facilitates interaction of the virion with host cell receptors. Nicotinic acetylcholine receptors were the first receptors identified as a molecular target for the rabies virus. Additional targets, including neural cell adhesion molecule, p75 neurotrophin receptor, metabotropic glutamate receptor subtype 2, and integrin ß1, have been added to the list, all of which can mediate viral entry into the cell. Multiple receptors and different subtypes of nicotinic acetylcholine receptors result in a complex picture of virus-receptor interactions. In addition, some data suggest that the rabies virus glycoprotein inhibits cell signaling events mediated by various nicotinic receptor subtypes that have been implicated in altering behavior in unaffected animals. This review focuses on interactions between the rabies virus glycoprotein and nicotinic receptors and proposes possible functional consequences, including behavioral modifications and therapeutic approaches for future research.

10.
PLoS One ; 17(9): e0274100, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36137156

RESUMO

BACKGROUND: The lack of race/ethnic and gender diversity in grants funded by the National Institutes of Health (NIH) is a persistent challenge related to career advancement and the quality and relevance of health research. We describe pilot programs at nine institutions supported by the NIH-sponsored Building Infrastructure Leading to Diversity (BUILD) program aimed at increasing diversity in biomedical research. METHODS: We collected data from the 2016-2017 Higher Education Research Institute survey of faculty and NIH progress reports for the first four years of the program (2015-2018). We then conducted descriptive analyses of data from the nine BUILD institutions that had collected data and evaluated which activities were associated with research productivity. We used Poisson regression and rate ratios of the numbers of BUILD pilots funded, students included, abstracts, presentations, publications, and submitted and funded grant proposals. RESULTS: Teaching workshops were associated with more abstracts (RR 4.04, 95% CI 2.21-8.09). Workshops on grant writing were associated with more publications (RR 2.64, 95% CI 1.64-4.34) and marginally with marginally more presentations. Incentives to develop courses were associated with more abstracts published (RR 4.33, 95% CI 2.56-7.75). Workshops on research skills and other incentives were not associated with any positive effects. CONCLUSIONS: Pilot interventions show promise in supporting diversity in NIH-level research. Longitudinal modeling that considers time lags in career development in moving from project development to grants submissions can provide more direction for future diversity pilot interventions.


Assuntos
Pesquisa Biomédica , Organização do Financiamento , Academias e Institutos , Humanos , National Institutes of Health (U.S.) , Estados Unidos , Redação
11.
Microbiology (Reading) ; 157(Pt 12): 3483-3491, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21980115

RESUMO

The Francisella pathogenicity island (FPI) encodes proteins thought to compose a type VI secretion system (T6SS) that is required for the intracellular growth of Francisella novicida. In this work we used deletion mutagenesis and genetic complementation to determine that the intracellular growth of F. novicida was dependent on 14 of the 18 genes in the FPI. The products of the iglABCD operon were localized by the biochemical fractionation of F. novicida, and Francisella tularensis LVS. Sucrose gradient separation of water-insoluble material showed that the FPI-encoded proteins IglA, IglB and IglC were found in multiple fractions, especially in a fraction that did not correspond to a known membrane fraction. We interpreted these data to suggest that IglA, IglB and IglC are part of a macromolecular structure. Analysis of published structural data suggested that IglC is an analogue of Hcp, which is thought to form long nano-tubes. Thus the fractionation properties of IglA, IglB and IglC are consistent with the current model of the T6SS apparatus, which supposes that IglA and IglB homologues form an outer tube structure that surrounds an inner tube composed of Hcp (IglC) subunits. Fractionation of F. novicida expressing FLAG-tagged DotU (IcmH homologue) and PdpB (IcmF homologue) showed that these proteins localize to the inner membrane. Deletion of dotU led to the cleavage of PdpB, suggesting an interaction of these two proteins that is consistent with results obtained with other T6SSs. Our results may provide a mechanistic basis for many of the studies that have examined the virulence properties of Francisella mutants in FPI genes, namely that the observed phenotypes of the mutants are the result of the disruption of the FPI-encoded T6SS structure.


Assuntos
Francisella/genética , Francisella/metabolismo , Ilhas Genômicas , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Membrana Celular/química , Francisella/crescimento & desenvolvimento , Deleção de Genes , Teste de Complementação Genética , Proteínas de Membrana Transportadoras/isolamento & purificação , Modelos Moleculares , Multimerização Proteica , Fatores de Virulência/isolamento & purificação
12.
J Zoo Wildl Med ; 42(1): 108-12, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22946378

RESUMO

A spotted seal harvested by subsistence hunters in Kotzebue Sound, Alaska (USA), showed a grossly enlarged uterus and associated lymph nodes. Streptococcus phocae was isolated from the purulent uterine discharge. Histopathologic examination revealed inflammation that was limited to the uterine mucosa. Lymph nodes draining the affected organ were reactive but no evidence of active infection was found in the lymph nodes. This report is the first Streptococcus phocae isolated from spotted seals as well as the first report of pyometra as the main pathologic finding associated with this pathogen. Isolation of this pathogen from Alaska expands the reported range to arctic pinnipeds. Zoonotic potential remains unknown.


Assuntos
Phoca , Piometra/veterinária , Infecções Estreptocócicas/veterinária , Streptococcus/isolamento & purificação , Alaska/epidemiologia , Animais , Feminino , Filogenia , Piometra/epidemiologia , Piometra/microbiologia , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus/classificação , Streptococcus/genética
13.
Zoonoses Public Health ; 68(6): 677-683, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33955689

RESUMO

The ecology of rabies in the circumpolar North is still not well understood. We use machine learning, a geographic information system and data explicit in time and space obtained for reported rabies cases and predictors in Canada to develop an ecological niche model for the distribution of reported rabies cases in the American north (Alaska and Canada). The ecological niche model based on reported rabies cases in Canada predicted reported rabies cases in Alaska, suggesting a rather robust inference and even similar drivers on a continental scale. As found in Alaska, proximity to human infrastructure-specifically along the coast-was a strong predictor in the detection of rabies cases in Canada. Also, this finding highlights the need for a more systematic landscape sampling for rabies infection model predictions to better understand and tackle the ecology of this important zoonotic disease on a landscape scale at some distance from human infrastructure in wilderness areas.


Assuntos
Animais Selvagens , Gado , Modelos Biológicos , Animais de Estimação , Raiva/veterinária , Alaska/epidemiologia , Animais , Canadá/epidemiologia , Demografia , Ecossistema , Sistemas de Informação Geográfica , Humanos , Raiva/epidemiologia , Zoonoses Virais
14.
PLoS One ; 16(10): e0258975, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34714859

RESUMO

Patterns of local adaptation can emerge in response to the selective pressures diseases exert on host populations as reflected in increased frequencies of respective, advantageous genotypes. Elucidating patterns of local adaptation enhance our understanding of mechanisms of disease spread and the capacity for species to adapt in context of rapidly changing environments such as the Arctic. Arctic rabies is a lethal disease that largely persists in northern climates and overlaps with the distribution of its natural host, arctic fox. Arctic fox populations display little neutral genetic structure across their North American range, whereas phylogenetically unique arctic rabies variants are restricted in their geographic distributions. It remains unknown if arctic rabies variants impose differential selection upon host populations, nor what role different rabies variants play in the maintenance and spread of this disease. Using a targeted, genotyping-by-sequencing assay, we assessed correlations of arctic fox immunogenetic variation with arctic rabies variants to gain further insight into the epidemiology of this disease. Corroborating past research, we found no neutral genetic structure between sampled regions, but did find moderate immunogenetic structuring between foxes predominated by different arctic rabies variants. FST outliers associated with host immunogenetic structure included SNPs within interleukin and Toll-like receptor coding regions (IL12B, IL5, TLR3 and NFKB1); genes known to mediate host responses to rabies. While these data do not necessarily reflect causation, nor a direct link to arctic rabies, the contrasting genetic structure of immunologically associated candidate genes with neutral loci is suggestive of differential selection and patterns of local adaptation in this system. These data are somewhat unexpected given the long-lived nature and dispersal capacities of arctic fox; traits expected to undermine local adaptation. Overall, these data contribute to our understanding of the co-evolutionary relationships between arctic rabies and their primary host and provide data relevant to the management of this disease.


Assuntos
Animais Selvagens/virologia , Raposas/virologia , Vírus da Raiva/genética , Raiva , Animais , Regiões Árticas , Evolução Biológica , Genótipo , Raiva/epidemiologia , Raiva/veterinária , Raiva/virologia
15.
PLoS One ; 16(4): e0249176, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33831031

RESUMO

Populations are exposed to different types and strains of pathogens across heterogeneous landscapes, where local interactions between host and pathogen may present reciprocal selective forces leading to correlated patterns of spatial genetic structure. Understanding these coevolutionary patterns provides insight into mechanisms of disease spread and maintenance. Arctic rabies (AR) is a lethal disease with viral variants that occupy distinct geographic distributions across North America and Europe. Red fox (Vulpes vulpes) are a highly susceptible AR host, whose range overlaps both geographically distinct AR strains and regions where AR is absent. It is unclear if genetic structure exists among red fox populations relative to the presence/absence of AR or the spatial distribution of AR variants. Acquiring these data may enhance our understanding of the role of red fox in AR maintenance/spread and inform disease control strategies. Using a genotyping-by-sequencing assay targeting 116 genomic regions of immunogenetic relevance, we screened for sequence variation among red fox populations from Alaska and an outgroup from Ontario, including areas with different AR variants, and regions where the disease was absent. Presumed neutral SNP data from the assay found negligible levels of neutral genetic structure among Alaskan populations. The immunogenetically-associated data identified 30 outlier SNPs supporting weak to moderate genetic structure between regions with and without AR in Alaska. The outliers included SNPs with the potential to cause missense mutations within several toll-like receptor genes that have been associated with AR outcome. In contrast, there was a lack of genetic structure between regions with different AR variants. Combined, we interpret these data to suggest red fox populations respond differently to the presence of AR, but not AR variants. This research increases our understanding of AR dynamics in the Arctic, where host/disease patterns are undergoing flux in a rapidly changing Arctic landscape, including the continued northward expansion of red fox into regions previously predominated by the arctic fox (Vulpes lagopus).


Assuntos
Raposas/genética , Polimorfismo de Nucleotídeo Único , Raiva/genética , Alaska , Doenças dos Animais/epidemiologia , Doenças dos Animais/genética , Doenças dos Animais/virologia , Distribuição Animal , Animais , Raposas/virologia , Haplótipos , Mutação de Sentido Incorreto , Ontário , Raiva/epidemiologia , Raiva/virologia , Vírus da Raiva/isolamento & purificação , Vírus da Raiva/patogenicidade , Receptores Toll-Like/genética
16.
Front Public Health ; 9: 627654, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026707

RESUMO

The COVID-19 pandemic has re-focused attention on mechanisms that lead to zoonotic disease spillover and spread. Commercial wildlife trade, and associated markets, are recognized mechanisms for zoonotic disease emergence, resulting in a growing global conversation around reducing human disease risks from spillover associated with hunting, trade, and consumption of wild animals. These discussions are especially relevant to people who rely on harvesting wildlife to meet nutritional, and cultural needs, including those in Arctic and boreal regions. Global policies around wildlife use and trade can impact food sovereignty and security, especially of Indigenous Peoples. We reviewed known zoonotic pathogens and current risks of transmission from wildlife (including fish) to humans in North American Arctic and boreal biomes, and evaluated the epidemic and pandemic potential of these zoonoses. We discuss future concerns, and consider monitoring and mitigation measures in these changing socio-ecological systems. While multiple zoonotic pathogens circulate in these systems, risks to humans are mostly limited to individual illness or local community outbreaks. These regions are relatively remote, subject to very cold temperatures, have relatively low wildlife, domestic animal, and pathogen diversity, and in many cases low density, including of humans. Hence, favorable conditions for emergence of novel diseases or major amplification of a spillover event are currently not present. The greatest risk to northern communities from pathogens of pandemic potential is via introduction with humans visiting from other areas. However, Arctic and boreal ecosystems are undergoing rapid changes through climate warming, habitat encroachment, and development; all of which can change host and pathogen relationships, thereby affecting the probability of the emergence of new (and re-emergence of old) zoonoses. Indigenous leadership and engagement in disease monitoring, prevention and response, is vital from the outset, and would increase the success of such efforts, as well as ensure the protection of Indigenous rights as outlined in the United Nations Declaration on the Rights of Indigenous Peoples. Partnering with northern communities and including Indigenous Knowledge Systems would improve the timeliness, and likelihood, of detecting emerging zoonotic risks, and contextualize risk assessments to the unique human-wildlife relationships present in northern biomes.


Assuntos
Animais Selvagens , COVID-19 , Animais , Regiões Árticas , Ecossistema , Humanos , Pandemias/prevenção & controle , SARS-CoV-2 , Estados Unidos , Zoonoses/epidemiologia
17.
J Med Entomol ; 47(4): 639-48, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20695280

RESUMO

Tularemia is a zoonotic disease caused by the Category A bioterrorism agent Francisella tularensis. In Scandinavia, tularemia transmission by mosquitoes has been widely cited in the literature. We tested >2,500 mosquitoes captured in Alaska and found Francisella DNA in 30% of pooled samples. To examine the potential for transmission of Francisella by mosquitoes, we developed a mosquito model of Francisella infection. Larvae of Anopheles gambiae Giles and Aedes aegypti (L.) readily ingest F. tularensis but do not efficiently transfer infective doses of the bacterium to the pupal or adult stage. After a bloodmeal containing Francisella, adult female An. gambiae and Ae. aegypti retained detectable levels of Francisella DNA for 3 d, but when they took a second bloodmeal, the mammalian host was not infected. This study suggests that although Francisella DNA can be detected in a significant portion of wild-caught mosquitoes, transmission of Francisella is either very inefficient or is species dependent for the Francisella strain or the arthropod vector.


Assuntos
Culicidae/microbiologia , Francisella tularensis/isolamento & purificação , Insetos Vetores/microbiologia , Tularemia/transmissão , Alaska/epidemiologia , Animais , DNA Bacteriano/isolamento & purificação , Feminino , Metamorfose Biológica , Camundongos , Pupa/microbiologia , Tularemia/epidemiologia , Tularemia/microbiologia
18.
Ecohealth ; 17(1): 174-180, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32006181

RESUMO

A 2016 outbreak of anthrax on the Yamal Peninsula in Siberia that led to the culling of more than two hundred thousand reindeer and killed one human, resulted in significant media interests and in the reporting was often linked to thawing permafrost and ultimately climate change. Here, we review the historic context of anthrax outbreaks in the circumpolar North and explore alternative explanations for the anthrax outbreak in Western Siberia. Further, we propose a convergence model where multiple factors likely contributed to the outbreak of anthrax, including an expanded population and discontinued vaccination.


Assuntos
Antraz/epidemiologia , Animais , Antraz/veterinária , Regiões Árticas/epidemiologia , Bacillus anthracis , Mudança Climática , Surtos de Doenças , Humanos , Rena/microbiologia , Sibéria , Vacinação
19.
Ethn Dis ; 30(4): 681-692, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32989368

RESUMO

Objective: The biomedical/behavioral sciences lag in the recruitment and advancement of students from historically underrepresented backgrounds. In 2014 the NIH created the Diversity Program Consortium (DPC), a prospective, multi-site study comprising 10 Building Infrastructure Leading to Diversity (BUILD) institutional grantees, the National Research Mentoring Network (NRMN) and a Coordination and Evaluation Center (CEC). This article describes baseline characteristics of four incoming, first-year student cohorts at the primary BUILD institutions who completed the Higher Education Research Institute, The Freshmen Survey between 2015-2019. These freshmen are the primary student cohorts for longitudinal analyses comparing outcomes of BUILD program participants and non-participants. Design: Baseline description of first-year students entering college at BUILD institutions during 2015-2019. Setting: Ten colleges/universities that each received <$7.5mil/yr in NIH Research Project Grants and have high proportions of low-income students. Participants: First-year undergraduate students who participated in BUILD-sponsored activities and a sample of non-BUILD students at the same BUILD institutions. A total of 32,963 first-year students were enrolled in the project; 64% were female, 18% Hispanic/Latinx, 19% African American/Black, 2% American Indian/Alaska Native and Native Hawaiian/Pacific Islander, 17% Asian, and 29% White. Twenty-seven percent were from families with an income <$30,000/yr and 25% were their family's first generation in college. Planned Outcomes: Primary student outcomes to be evaluated over time include undergraduate biomedical degree completion, entry into/completion of a graduate biomedical degree program, and evidence of excelling in biomedical research and scholarship. Conclusions: The DPC national evaluation has identified a large, longitudinal cohort of students with many from groups historically underrepresented in the biomedical sciences that will inform institutional/national policy level initiatives to help diversify the biomedical workforce.


Assuntos
Pesquisa Biomédica/educação , Diversidade Cultural , Programas Governamentais/estatística & dados numéricos , Estudantes/estatística & dados numéricos , Universidades , Adolescente , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Asiático/estatística & dados numéricos , Escolaridade , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Renda/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.)/economia , Havaiano Nativo ou Outro Ilhéu do Pacífico/estatística & dados numéricos , Estudos Prospectivos , Inquéritos e Questionários , Estados Unidos , População Branca/estatística & dados numéricos , Recursos Humanos , Adulto Jovem , Indígena Americano ou Nativo do Alasca/estatística & dados numéricos
20.
Int J Circumpolar Health ; 78(1): 1607502, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31023174

RESUMO

The North faces significant health disparities, especially among its many Indigenous peoples. In this article we discuss historical, environmental, and cultural variables that contribute to these disparities and propose a One Health approach to address them in a holistic and culturally appropriate manner. The One Health paradigm recognizes the interdependence among the health and well-being of people, animals and the environment. As such, the framework aligns well with many Indigenous world views. This proactive, interdisciplinary, constructivist, and collaborative approach promise earlier detection of risks and threats, as well as more effective responses, in part by engaging community level stakeholders in all stages of the process. In the far North, humans, especially Indigenous peoples, continue to live closely connected to their environment, in settings that exert significant impacts on health. In recent decades, rapid warming and elevated contaminant levels have heightened environmental risks and increased uncertainty, both of which threaten individual and community health and well-being. Under these circumstances especially, One Health's comprehensive approach may provide mitigating and adaptive strategies to enhance resilience. While many of the examples used in this manuscript focus on Alaska and Canada, the authors believe similar conditions exist among the indigenous and rural residents across the entire Circumpolar North.


Assuntos
Características Culturais , Meio Ambiente , Inuíte , Saúde Única , Alaska , Animais , Regiões Árticas , Canadá , Mudança Climática , Comportamento Cooperativo , Humanos , Saúde Mental/etnologia , Fatores de Risco , Meio Social , Fatores Socioeconômicos , Zoonoses/epidemiologia
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