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1.
PLoS Pathog ; 20(2): e1012007, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38386661

RESUMO

Smallpox was the most rampant infectious disease killer of the 20th century, yet much remains unknown about the pathogenesis of the variola virus. Using archived tissue from a study conducted at the Centers for Disease Control and Prevention we characterized pathology in 18 cynomolgus macaques intravenously infected with the Harper strain of variola virus. Six macaques were placebo-treated controls, six were tecovirimat-treated beginning at 2 days post-infection, and six were tecovirimat-treated beginning at 4 days post-infection. All macaques were treated daily until day 17. Archived tissues were interrogated using immunohistochemistry, in situ hybridization, immunofluorescence, and electron microscopy. Gross lesions in three placebo-treated animals that succumbed to infection primarily consisted of cutaneous vesicles, pustules, or crusts with lymphadenopathy. The only gross lesions noted at the conclusion of the study in the three surviving placebo-treated and the Day 4 treated animals consisted of resolving cutaneous pox lesions. No gross lesions attributable to poxviral infection were present in the Day 2 treated macaques. Histologic lesions in three placebo-treated macaques that succumbed to infection consisted of proliferative and necrotizing dermatitis with intracytoplasmic inclusion bodies and lymphoid depletion. The only notable histologic lesion in the Day 4 treated macaques was resolving dermatitis; no notable lesions were seen in the Day 2 treated macaques. Variola virus was detected in all three placebo-treated animals that succumbed to infection prior to the study's conclusion by all utilized methods (IHC, ISH, IFA, EM). None of the three placebo-treated animals that survived to the end of the study nor the animals in the two tecovirimat treatment groups showed evidence of variola virus by these methods. Our findings further characterize variola lesions in the macaque model and describe new molecular methods for variola detection.


Assuntos
Dermatite , Varíola , Vírus da Varíola , Animais , Benzamidas , Isoindóis , Macaca fascicularis , Varíola/tratamento farmacológico , Varíola/patologia , Estados Unidos
2.
Microbiol Spectr ; 12(4): e0358623, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38391232

RESUMO

Although smallpox has been eradicated, other orthopoxviruses continue to be a public health concern as exemplified by the ongoing Mpox (formerly monkeypox) global outbreak. While medical countermeasures (MCMs) previously approved by the Food and Drug Administration for the treatment of smallpox have been adopted for Mpox, previously described vulnerabilities coupled with the questionable benefit of at least one of the therapeutics during the 2022 Mpox outbreak reinforce the need for identifying and developing other MCMs against orthopoxviruses. Here, we screened a panel of Merck proprietary small molecules and identified a novel nucleoside inhibitor with potent broad-spectrum antiviral activity against multiple orthopoxviruses. Efficacy testing of a 7-day dosing regimen of the orally administered nucleoside in a murine model of severe orthopoxvirus infection yielded a dose-dependent increase in survival. Treated animals had greatly reduced lesions in the lung and nasal cavity, particularly in the 10 µg/mL dosing group. Viral levels were also markedly lower in the UMM-766-treated animals. This work demonstrates that this nucleoside analog has anti-orthopoxvirus efficacy and can protect against severe disease in a murine orthopox model.IMPORTANCEThe recent monkeypox virus pandemic demonstrates that members of the orthopoxvirus, which also includes variola virus, which causes smallpox, remain a public health issue. While currently FDA-approved treatment options exist, risks that resistant strains of orthopoxviruses may arise are a great concern. Thus, continued exploration of anti-poxvirus treatments is warranted. Here, we developed a template for a high-throughput screening assay to identify anti-poxvirus small-molecule drugs. By screening available drug libraries, we identified a compound that inhibited orthopoxvirus replication in cell culture. We then showed that this drug can protect animals against severe disease. Our findings here support the use of existing drug libraries to identify orthopoxvirus-targeting drugs that may serve as human-safe products to thwart future outbreaks.


Assuntos
Mpox , Orthopoxvirus , Varíola , Vírus da Varíola , Animais , Camundongos , Humanos , Nucleosídeos/uso terapêutico , Varíola/tratamento farmacológico , Varíola/prevenção & controle , Modelos Animais de Doenças
3.
Can J Neurol Sci ; 51(1): 78-86, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36715071

RESUMO

BACKGROUND & AIMS: It is unknown if the COVID-19 pandemic and public health measures had an immediate impact on stroke subtypes and etiologies in patients not infected with COVID-19. We aimed to evaluate if the proportion of non-COVID-19-related stroke subtypes (ischemic vs. hemorrhagic) and etiologies (cardioembolic, atherosclerosis, small vessel disease, and others) during the pandemic's first wave were different from prepandemic. METHODS: For this retrospective cohort study, we included patients without COVID-19 with ischemic or hemorrhagic stroke at two large Canadian stroke centers between March-May 2019 (prepandemic cohort) and March-May 2020 (pandemic cohort). Proportions of stroke subtypes and etiologies were compared between cohorts using chi-square tests. RESULTS: The prepandemic cohort consisted of 234 stroke patients and the pandemic cohort of 207 stroke patients. There were no major differences in baseline characteristics. The proportions of ischemic versus hemorrhagic stroke were similar (ischemic stroke: 77% prepandemic vs. 75% pandemic; hemorrhagic stroke:12% prepandemic vs. 14% pandemic; p > 0.05). There were no differences in etiologies, except for a decreased proportion of ischemic stroke due to atherosclerosis in the pandemic cohort (26% prepandemic vs. 15% pandemic; difference: 10.6%, 95%CI: 1.4-19.7; p = 0.03). Notably, during the pandemic, the cause of ischemic stroke was more often unknown because of incomplete work-up (13.3% prepandemic vs. 28.2% pandemic, difference: 14.9%, 95%-CI: 5.7-24.2; p = <0.01). CONCLUSIONS: In this study, the pandemic had no clear effect on stroke subtypes and etiologies suggesting a limited impact of the pandemic on stroke triggers. However, the shift from atherosclerosis toward other causes warrants further exploration.


Assuntos
Aterosclerose , COVID-19 , Acidente Vascular Cerebral Hemorrágico , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , COVID-19/epidemiologia , Pandemias , Estudos Retrospectivos , Canadá/epidemiologia , Acidente Vascular Cerebral/epidemiologia
4.
Front Microbiol ; 14: 1243523, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37744911

RESUMO

Human monkeypox (mpox) has recently become a global public health emergency; however, assays that detect mpox infection are not widely available, largely due to cross-reactivity within the Orthopoxvirus genus. Immunoassay development was largely confined to researchers who focus on biothreats and endemic areas (Central and West Africa) until the 2022 outbreak. As was noted in the COVID-19 pandemic, antigen detection assays, integrated with molecular assays, are necessary to help curb the spread of disease. Antigen-detecting immunoassays offer the advantage of providing results ranging from within min to h and in lateral flow formats; they can be deployed for point-of-care, home, or field use. This study reports the development of an mpox-specific antigen detection immunoassay developed on a multiplexed, magnetic-bead-based platform utilizing reagents from all research sectors (commercial, academic, and governmental). Two semi-quantitative assays were developed in parallel and standardized with infectious mpox virus (MPXV) cell culture fluid and MPXV-positive non-human primate (NHP) sera samples. These assays could detect viral antigens in serum, were highly specific toward MPXV as compared to other infectious orthopoxviruses (vaccinia virus, cowpox virus, and camelpox virus), and exhibited a correlation with quantitative PCR results from an NHP study. Access to a toolbox of assays for mpox detection will be key for identifying cases and ensuring proper treatment, as MPXV is currently a global traveler.

5.
PLoS Negl Trop Dis ; 17(9): e0011620, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37682988

RESUMO

Numerous arenaviruses have been identified throughout the Americas and a subset of these viruses cause viral hemorrhagic fever in humans. This study compared the pathology and viral RNA distribution in Hartley guinea pigs challenged with two human-disease causing New World arenaviruses, Junin virus (JUNV) or Guanarito virus (GTOV). Histopathologic analysis and RNA in situ hybridization revealed similar pathology and viral RNA distribution for both groups of animals challenged with either JUNV or GTOV on days 3, 7, 10 and 12 post exposure (PE). Gross lesions were first observed on day 7 and primarily involved the lungs and liver. The most severe histologic lesions occurred in the lymph nodes, spleen, and thymus and included lymphoid depletion and necrosis which increased in severity over time. Extensive necrosis was also observed in the bone marrow on day 12. Minimal to mild inflammation with and without necrosis was observed in the choroid plexus of the brain, choroid of the eye, intestinal tract, lung and adrenal gland. Significant liver lesions were rare, consisting predominantly of hepatocyte vacuolation. Viral RNA labeling was identified in nearly all organs examined, was often extensive in certain organs and generally increased over time starting on day 7. Our data demonstrate the guinea pig may serve as a useful model to study New World arenavirus infection in humans and for the evaluation and development of medical countermeasures.


Assuntos
Arenavirus do Novo Mundo , Vírus Junin , Humanos , Cobaias , Animais , RNA Viral/genética , Fígado , Encéfalo
6.
J Christ Nurs ; 40(3): 184-190, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36787474

RESUMO

ABSTRACT: One out of five Medicare beneficiaries is readmitted within 30 days after hospital discharge, and as many as three in four readmissions are preventable. This study describes transitional care interventions (TCIs) delivered by one faith community nurse (FCN) to at-risk seniors living in a certain ZIP code. Two years of nursing documentation (2,280 interventions) were translated into Nursing Interventions Classification standardized nursing language. Results indicate the FCN provided priority TCIs including spiritual care. In fully describing TCIs using a nursing language, results support that the FCN transitional care model is a method worth exploring to provide wholistic transitional care.


Assuntos
Enfermagem Paroquial , Terminologia Padronizada em Enfermagem , Cuidado Transicional , Idoso , Humanos , Estados Unidos , Medicare , Alta do Paciente
7.
Nurse Educ ; 48(1): 43-48, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35977345

RESUMO

BACKGROUND: Nurse practitioner (NP) faculty assess student acquisition of knowledge through examinations, simulation, and clinical performance. PROBLEM: Developing appropriately leveled curriculum, assessments, and clinical expectations that accurately capture student maturation presents a challenge. APPROACH: The Reporter, Interpreter, Manager, Educator (RIME) provided the framework for doctor of nursing practice NP curriculum redesign to enhance student performance and content mastery. Faculty used a gap analysis approach, iteratively leveling specialty content, course competencies, examination questions, simulation cases, and clinical expectations using the building blocks of RIME. OUTCOMES: Objective scores on student evaluations for clinical courses exceeded the threshold established, including 83% of simulation encounters. Faculty implemented targeted methods to remediate areas of underperformance. CONCLUSIONS: Structuring the course competencies and preceptor feedback around RIME made it easier to pinpoint specific deficiencies and target remediation. It also helped guide discussions about the minimum acceptable standard for student performance.


Assuntos
Currículo , Profissionais de Enfermagem , Humanos , Pesquisa em Educação em Enfermagem
8.
Nat Commun ; 13(1): 5392, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104331

RESUMO

Perinatal infection with Streptococcus agalactiae, or Group B Streptococcus (GBS), is associated with preterm birth, neonatal sepsis, and stillbirth. Here, we study the interactions of GBS with macrophages, essential sentinel immune cells that defend the gravid reproductive tract. Transcriptional analyses of GBS-macrophage co-cultures reveal enhanced expression of a gene encoding a putative metal resistance determinant, cadD. Deletion of cadD reduces GBS survival in macrophages, metal efflux, and resistance to metal toxicity. In a mouse model of ascending infection during pregnancy, the ΔcadD strain displays attenuated bacterial burden, inflammation, and cytokine production in gestational tissues. Furthermore, depletion of host macrophages alters cytokine expression and decreases GBS invasion in a cadD-dependent fashion. Our results indicate that GBS cadD plays an important role in metal detoxification, which promotes immune evasion and bacterial proliferation in the pregnant host.


Assuntos
Nascimento Prematuro , Streptococcus agalactiae , Animais , Citocinas , Feminino , Humanos , Recém-Nascido , Contagem de Leucócitos , Macrófagos/microbiologia , Metais , Camundongos , Gravidez , Nascimento Prematuro/microbiologia , Streptococcus agalactiae/genética
9.
PLoS Negl Trop Dis ; 16(5): e0010081, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35533188

RESUMO

Eastern equine encephalitis virus (EEEV) is mosquito-borne virus that produces fatal encephalitis in humans. We recently conducted a first of its kind study to investigate EEEV clinical disease course following aerosol challenge in a cynomolgus macaque model utilizing the state-of-the-art telemetry to measure critical physiological parameters. Here, we report the results of a comprehensive pathology study of NHP tissues collected at euthanasia to gain insights into EEEV pathogenesis. Viral RNA and proteins as well as microscopic lesions were absent in the visceral organs. In contrast, viral RNA and proteins were readily detected throughout the brain including autonomic nervous system (ANS) control centers and spinal cord. However, despite presence of viral RNA and proteins, majority of the brain and spinal cord tissues exhibited minimal or no microscopic lesions. The virus tropism was restricted primarily to neurons, and virus particles (~61-68 nm) were present within axons of neurons and throughout the extracellular spaces. However, active virus replication was absent or minimal in majority of the brain and was limited to regions proximal to the olfactory tract. These data suggest that EEEV initially replicates in/near the olfactory bulb following aerosol challenge and is rapidly transported to distal regions of the brain by exploiting the neuronal axonal transport system to facilitate neuron-to-neuron spread. Once within the brain, the virus gains access to the ANS control centers likely leading to disruption and/or dysregulation of critical physiological parameters to produce severe disease. Moreover, the absence of microscopic lesions strongly suggests that the underlying mechanism of EEEV pathogenesis is due to neuronal dysfunction rather than neuronal death. This study is the first comprehensive investigation into EEEV pathology in a NHP model and will provide significant insights into the evaluation of countermeasure.


Assuntos
Vírus da Encefalite Equina do Leste , Encefalomielite Equina , Aerossóis , Animais , Encéfalo , Modelos Animais de Doenças , Encefalomielite Equina/patologia , Cavalos , Macaca fascicularis , RNA Viral , Medula Espinal/patologia
10.
Microbiology (Reading) ; 168(3)2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35293855

RESUMO

Type IV pili are involved in adhesion, twitching motility, aggregation, biofilm formation and virulence in a variety of Gram-negative bacteria. Burkholderia pseudomallei, the causative agent of melioidosis and a Tier 1 biological select agent, is a Gram-negative bacterium with eight type IV pili-associated loci (TFP1 to TFP8). Most have not been fully characterized. In this study, we investigated BPSS2185, an uncharacterized TFP8 gene that encodes a type IVB pilus protein subunit. Using genetic deletion and complementation analysis in B. pseudomallei JW270, we demonstrate that BPSS2185 plays an important role in twitching motility and adhesion to A549 human alveolar epithelial cells. Compared to JW270, the JW270 ΔBPSS2185 mutant failed to display twitching motility and did not adhere to the epithelial cells. These phenotypes were partially reversed by the complementation of BPSS2185 in the mutant strain. The study also shows that BPSS2185 is expressed only during the onset of mature biofilm formation and at the dispersal of a biofilm, suggesting that the motility characteristic is required to form a biofilm. Our study is the first to suggest that the BPSS2185 gene in TFP8 contributes to twitching motility, adhesion and biofilm formation, indicating that the gene may contribute to B. pseudomallei virulence.


Assuntos
Burkholderia pseudomallei , Proteínas de Fímbrias , Biofilmes , Burkholderia pseudomallei/genética , Burkholderia pseudomallei/metabolismo , Células Epiteliais/metabolismo , Proteínas de Fímbrias/genética , Proteínas de Fímbrias/metabolismo , Fímbrias Bacterianas/genética , Fímbrias Bacterianas/metabolismo
11.
Sci Transl Med ; 14(631): eabi5229, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35138912

RESUMO

Effective therapeutics have been developed against acute Ebola virus disease (EVD) in both humans and experimentally infected nonhuman primates. However, the risk of viral persistence and associated disease recrudescence in survivors receiving these therapeutics remains unclear. In contrast to rhesus macaques that survived Ebola virus (EBOV) exposure in the absence of treatment, we discovered that EBOV, despite being cleared from all other organs, persisted in the brain ventricular system of rhesus macaque survivors that had received monoclonal antibody (mAb) treatment. In mAb-treated macaque survivors, EBOV persisted in macrophages infiltrating the brain ventricular system, including the choroid plexuses. This macrophage infiltration was accompanied by severe tissue damage, including ventriculitis, choroid plexitis, and meningoencephalitis. Specifically, choroid plexus endothelium-derived EBOV infection led to viral persistence in the macaque brain ventricular system. This resulted in apoptosis of ependymal cells, which constitute the blood-cerebrospinal fluid barrier of the choroid plexuses. Fatal brain-confined recrudescence of EBOV infection manifested as severe inflammation, local pathology, and widespread infection of the ventricular system and adjacent neuropil in some of the mAb-treated macaque survivors. This study highlights organ-specific EBOV persistence and fatal recrudescent disease in rhesus macaque survivors after therapeutic treatment and has implications for the long-term follow-up of human survivors of EVD.


Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Animais , Anticorpos Monoclonais , Encéfalo , Humanos , Macaca mulatta , Recidiva , Sobreviventes
12.
mBio ; 13(1): e0290621, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35073750

RESUMO

The rapid emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has created a global health emergency. While most human disease is mild to moderate, some infections lead to a severe disease characterized by acute respiratory distress, hypoxia, anosmia, ageusia, and, in some instances, neurological involvement. Small-animal models reproducing severe disease, including neurological sequela, are needed to characterize the pathophysiological mechanism(s) of disease and to identify medical countermeasures. Transgenic mice expressing the human angiotensin-converting enzyme 2 (hACE2) viral receptor under the control of the K18 promoter develop severe and lethal respiratory disease subsequent to SARS-CoV-2 intranasal challenge when high viral doses are used. Here, we report on SARS-CoV-2 infection of hamsters engineered to express the hACE2 receptor under the control of the K18 promoter. K18-hACE2 hamsters infected with a relatively low dose of 100 or 1,000 PFU of SARS-CoV-2 developed a severe and lethal disease, with most animals succumbing by day 5 postinfection. Hamsters developed severe lesions and inflammation within the upper and lower respiratory system, including infection of the nasal cavities causing marked destruction of the olfactory epithelium as well as severe bronchopneumonia that extended deep into the alveoli. Additionally, SARS-CoV-2 infection spread to the central nervous system (CNS), including the brain stem and spinal cord. Wild-type (WT) hamsters naturally support SARS-CoV-2 infection, with the primary lesions present in the respiratory tract and nasal cavity. Overall, infection in the K18-hACE2 hamsters is more extensive than that in WT hamsters, with more CNS involvement and a lethal outcome. These findings demonstrate the K18-hACE2 hamster model will be valuable for studying SARS-CoV-2. IMPORTANCE The rapid emergence of SARS-CoV-2 has created a global health emergency. While most human SARS-CoV-2 disease is mild, some people develop severe, life-threatening disease. Small-animal models mimicking the severe aspects of human disease are needed to more clearly understand the pathophysiological processes driving this progression. Here, we studied SARS-CoV-2 infection in hamsters engineered to express the human angiotensin-converting enzyme 2 viral receptor under the control of the K18 promoter. SARS-CoV-2 produces a severe and lethal infection in transgenic hamsters that mirrors the most severe aspects of COVID-19 in humans, including respiratory and neurological injury. In contrast to other animal systems, hamsters manifest disease with levels of input virus more consistent with natural human infection. This system will be useful for the study of SARS-CoV-2 disease and the development of drugs targeting this virus.


Assuntos
COVID-19 , SARS-CoV-2 , Camundongos , Animais , Cricetinae , Humanos , COVID-19/patologia , Enzima de Conversão de Angiotensina 2 , Peptidil Dipeptidase A , Pulmão/patologia , Camundongos Transgênicos , Modelos Animais de Doenças
13.
J Am Heart Assoc ; 10(23): e020094, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34796739

RESUMO

Background Depressive symptoms are associated with heightened risk of heart failure (HF), but their association with cardiac function and with HF with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF) in late life is unclear. We aimed to determine the prevalence of depression in HFpEF and in HFrEF in late life, and the association of depressive symptoms with cardiac function and incident HFpEF and HFrEF. Methods and Results We studied 6025 participants (age, 75.3±5.1 years; 59% women; 20% Black race) in the ARIC (Atherosclerosis Risk in Communities) study at visit 5 who underwent echocardiography and completed the Center for Epidemiologic Studies Depression Scale questionnaire. Among HF-free participants (n=5086), associations of Center for Epidemiologic Studies Depression Scale score with echocardiography and incident adjudicated HFpEF and HFrEF were assessed using multivariable linear and Cox proportional hazards regression. Prevalent HFpEF, but not HFrEF, was associated with a higher prevalence of depression compared with HF-free participants (P<0.001 and P=0.59, respectively). Among HF-free participants, Center for Epidemiologic Studies Depression Scale score was not associated with cardiac structure and function after adjusting for demographics and comorbidities (all P>0.05). Over 5.5-year follow-up, higher Center for Epidemiologic Studies Depression Scale score was associated with heightened risk of incident HFpEF (hazard ratio [HR] [95% CI], 1.06 [1.04-1.12]; P=0.02), but not HFrEF (HR [95% CI], 1.02 [0.96-1.08]; P=0.54), independent of echocardiographic measures, NT-proBNP (N-terminal pro-B-type natriuretic peptide), troponin, and hs-CRP (high-sensitivity C-reactive protein) (HR [95% CI], 1.06 [1.00-1.12]; P=0.04). Conclusions Worse depressive symptoms predict incident HFpEF in late life, independent of common comorbidities, cardiac structure and function, and prognostic biomarkers. Further studies are necessary to understand the mechanisms linking depression to risk of HFpEF.


Assuntos
Depressão , Insuficiência Cardíaca , Coração , Volume Sistólico , Idoso , Idoso de 80 Anos ou mais , Depressão/epidemiologia , Ecocardiografia , Feminino , Coração/anatomia & histologia , Coração/diagnóstico por imagem , Coração/fisiologia , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Medição de Risco , Volume Sistólico/fisiologia
14.
Front Cell Infect Microbiol ; 11: 808550, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35096655

RESUMO

Biofilms have been established as an important lifestyle for bacteria in nature as these structured communities often enable survivability and persistence in a multitude of environments. Francisella tularensis is a facultative intracellular Gram-negative bacterium found throughout much of the northern hemisphere. However, biofilm formation remains understudied and poorly understood in F. tularensis as non-substantial biofilms are typically observed in vitro by the clinically relevant subspecies F. tularensis subsp. tularensis and F. tularensis subsp. holarctica (Type A and B, respectively). Herein, we report conditions under which robust biofilm development was observed in a stochastic, but reproducible manner in Type A and B isolates. The frequency at which biofilm was observed increased temporally and appeared switch-like as progeny from the initial biofilm quickly formed biofilm in a predictable manner regardless of time or propagation with fresh media. The Type B isolates used for this study were found to more readily switch on biofilm formation than Type A isolates. Additionally, pH was found to function as an environmental checkpoint for biofilm initiation independently of the heritable cellular switch. Multiple colony morphologies were observed in biofilm positive cultures leading to the identification of a particular subset of grey variants that constitutively produce biofilm. Further, we found that constitutive biofilm forming isolates delay the onset of a viable non-culturable state. In this study, we demonstrate that a robust biofilm can be developed by clinically relevant F. tularensis isolates, provide a mechanism for biofilm initiation and examine the potential role of biofilm formation.


Assuntos
Francisella tularensis , Francisella , Tularemia , Biofilmes , Humanos , Lipopolissacarídeos , Variação de Fase , Tularemia/microbiologia
15.
J Infect Dis ; 224(4): 632-642, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-33367826

RESUMO

BACKGROUND: Ebola virus disease (EVD) supportive care strategies are largely guided by retrospective observational research. This study investigated the effect of EVD supportive care algorithms on duration of survival in a controlled nonhuman primate (NHP) model. METHODS: Fourteen rhesus macaques were challenged intramuscularly with a target dose of Ebola virus (1000 plaque-forming units; Kikwit). NHPs were allocated to intensive care unit (ICU)-like algorithms (n = 7), intravenous fluids plus levofloxacin (n = 2), or a control group (n = 5). The primary outcome measure was duration of survival, and secondary outcomes included changes in clinical laboratory values. RESULTS: Duration of survival was not significantly different between the pooled ICU-like algorithm and control groups (8.2 vs 6.9 days of survival; hazard ratio; 0.50; P = .25). Norepinephrine was effective in transiently maintaining baseline blood pressure. NHPs treated with ICU-like algorithms had delayed onset of liver and kidney injury. CONCLUSIONS: While an obvious survival difference was not observed with ICU-like care, clinical observations from this model may aid in EVD supportive care NHP model refinement.


Assuntos
Cuidados Críticos , Doença pelo Vírus Ebola , Unidades de Terapia Intensiva , Animais , Modelos Animais de Doenças , Ebolavirus , Doença pelo Vírus Ebola/terapia , Macaca mulatta , Primatas , Estudos Retrospectivos
16.
J Virol ; 94(22)2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-32900822

RESUMO

Animal models recapitulating human COVID-19 disease, especially severe disease, are urgently needed to understand pathogenesis and to evaluate candidate vaccines and therapeutics. Here, we develop novel severe-disease animal models for COVID-19 involving disruption of adaptive immunity in Syrian hamsters. Cyclophosphamide (CyP) immunosuppressed or RAG2 knockout (KO) hamsters were exposed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the respiratory route. Both the CyP-treated and RAG2 KO hamsters developed clinical signs of disease that were more severe than those in immunocompetent hamsters, notably weight loss, viral loads, and fatality (RAG2 KO only). Disease was prolonged in transiently immunosuppressed hamsters and was uniformly lethal in RAG2 KO hamsters. We evaluated the protective efficacy of a neutralizing monoclonal antibody and found that pretreatment, even in immunosuppressed animals, limited infection. Our results suggest that functional B and/or T cells are not only important for the clearance of SARS-CoV-2 but also play an early role in protection from acute disease.IMPORTANCE Syrian hamsters are in use as a model of disease caused by SARS-CoV-2. Pathology is pronounced in the upper and lower respiratory tract, and disease signs and endpoints include weight loss and viral RNA and/or infectious virus in swabs and organs (e.g., lungs). However, a high dose of virus is needed to produce disease, and the disease resolves rapidly. Here, we demonstrate that immunosuppressed hamsters are susceptible to low doses of virus and develop more severe and prolonged disease. We demonstrate the efficacy of a novel neutralizing monoclonal antibody using the cyclophosphamide transient suppression model. Furthermore, we demonstrate that RAG2 knockout hamsters develop severe/fatal disease when exposed to SARS-CoV-2. These immunosuppressed hamster models provide researchers with new tools for evaluating therapies and vaccines and understanding COVID-19 pathogenesis.


Assuntos
Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Modelos Animais de Doenças , Mesocricetus , Pneumonia Viral/imunologia , Pneumonia Viral/patologia , Imunidade Adaptativa , Animais , Animais Geneticamente Modificados , Betacoronavirus/fisiologia , COVID-19 , Ciclofosfamida , Proteínas de Ligação a DNA/genética , Técnicas de Inativação de Genes , Imunossupressores , Pandemias , SARS-CoV-2 , Índice de Gravidade de Doença
17.
Gastroenterology ; 158(8): 2236-2249.e9, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32112796

RESUMO

BACKGROUND & AIMS: Microvillus inclusion disease (MVID) is caused by inactivating mutations in the myosin VB gene (MYO5B). MVID is a complex disorder characterized by chronic, watery, life-threatening diarrhea that usually begins in the first hours to days of life. We developed a large animal model of MVID to better understand its pathophysiology. METHODS: Pigs were cloned by transfer of chromatin from swine primary fetal fibroblasts, which were edited with TALENs and single-strand oligonucleotide to introduce a P663-L663 substitution in the endogenous swine MYO5B (corresponding to the P660L mutation in human MYO5B, associated with MVID) to fertilized oocytes. We analyzed duodenal tissues from patients with MVID (with the MYO5B P660L mutation) and without (controls), and from pigs using immunohistochemistry. Enteroids were generated from pigs with MYO5B(P663L) and without the substitution (control pigs). RESULTS: Duodenal tissues from patients with MVID lacked MYO5B at the base of the apical membrane of intestinal cells; instead MYO5B was intracellular. Intestinal tissues and derived enteroids from MYO5B(P663L) piglets had reduced apical levels and diffuse subapical levels of sodium hydrogen exchanger 3 and SGLT1, which regulate transport of sodium, glucose, and water, compared with tissues from control piglets. However, intestinal tissues and derived enteroids from MYO5B(P663L) piglets maintained CFTR on apical membranes, like tissues from control pigs. Liver tissues from MYO5B(P663L) piglets had alterations in bile salt export pump, a transporter that facilitates bile flow, which is normally expressed in the bile canaliculi in the liver. CONCLUSIONS: We developed a large animal model of MVID that has many features of the human disease. Studies of this model could provide information about the functions of MYO5B and MVID pathogenesis, and might lead to new treatments.


Assuntos
Duodeno/metabolismo , Edição de Genes , Mucosa Intestinal/metabolismo , Síndromes de Malabsorção/genética , Microvilosidades/patologia , Mucolipidoses/genética , Cadeias Pesadas de Miosina/genética , Miosina Tipo V/genética , Transportador 1 de Glucose-Sódio/metabolismo , Trocador 3 de Sódio-Hidrogênio/metabolismo , Animais , Animais Geneticamente Modificados , Células Cultivadas , Técnicas de Cocultura , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Modelos Animais de Doenças , Duodeno/patologia , Predisposição Genética para Doença , Humanos , Mucosa Intestinal/patologia , Síndromes de Malabsorção/metabolismo , Síndromes de Malabsorção/patologia , Microvilosidades/genética , Microvilosidades/metabolismo , Mucolipidoses/metabolismo , Mucolipidoses/patologia , Mutação de Sentido Incorreto , Fenótipo , Sódio/metabolismo , Transportador 1 de Glucose-Sódio/genética , Trocador 3 de Sódio-Hidrogênio/genética , Sus scrofa
18.
J Health Care Poor Underserved ; 31(2): 635-645, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33410798

RESUMO

Communication training effectiveness for health care providers has been well documented, however patient and caregiver training may present a prime opportunity to mitigate communication challenges that provider-only training cannot. The aim of this study is to describe the multi-step process of adapting a national, provider, health communication training program (COMFORT) for use with underserved patients and caregivers who (1) are not regular consumers within health care systems and/or (2) do not have ready access to providers. We examine three iterations of training feedback for implementation in future training.


Assuntos
Comunicação em Saúde , Letramento em Saúde , Cuidadores , Pessoal de Saúde , Humanos , Populações Vulneráveis
19.
Arch Rehabil Res Clin Transl ; 2(3): 100062, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33543088

RESUMO

OBJECTIVES: We describe recruitment feasibility for language screening in acute stroke using the English adaptation the Language Screening Test (LASTen), originally developed in French. We also elucidate preliminary measurement properties of LASTen in patients with and without aphasia. DESIGN: Prospective eligibility tracking, recruitment, and screening for aphasia using the 2 parallel forms, LASTen-A and LASTen-B. SETTING: The Neurovascular Unit and the Transient Ischemic Attack and Minor Stroke Unit of a tertiary care hospital. PARTICIPANTS: Stroke patients (N=12) with hyperacute to subacute stroke. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Numbers of eligible patients and recruitment viability, individual performance indicators for both LASTen versions (15 points each) in 12 patients grouped by aphasia status, and reliability of the 2 parallel forms. RESULTS: There were 25 eligible stroke patients over 1 month. All 12 recruited patients consented to testing. The patients ranged in age from 29 to 85 years, and 5 were women. Three patients had intracerebral hemorrhage, and 6 had aphasia (mild to severe). The median LASTen scores in patients with and without aphasia were 10 (interquartile range, 8) and 15 (interquartile range, 0), respectively. Five patients had discrepant scores across versions involving a 1-point difference. One patient with aphasia had a 5-point difference, demonstrating improvement on the second version. The Pearson correlation coefficient was 0.95 for parallel form reliability. CONCLUSIONS: Our study confirmed that LASTen appears to function as designed. There was score heterogeneity for patients with aphasia and desired ceiling effects for those without aphasia, alongside excellent parallel form reliability. The findings provide the impetus for a large-scale diagnostic accuracy trial in acute stroke patients.

20.
J Intellect Disabil ; 24(2): 177-193, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30003830

RESUMO

There is an appropriate increasing focus on the need to ensure the voices of people with intellectual disability are captured as part of assessing individuals' quality of life; however, there remains a lack of a consensus on ways to achieve this. This article describes the development of a self-report measure of quality of life for people with intellectual disability, the 'Mini-MANS-LD', based on the concepts of Maslow's hierarchy of needs. Following use with 33 individuals with intellectual disability, the Mini-MANS-LD was found to have acceptable psychometric properties, including moderate congruent validity and acceptable internal consistency. Administrators' feedback suggested good acceptability and feasibility, and the measure was relatively quick to administer, easy to use and acceptable to service users. Despite a small sample size, this initial study suggests that the Mini-MANS-LD may present a conceptually relevant, feasible and acceptable self-report measure of quality of life for people with intellectual disability.


Assuntos
Deficiência Intelectual/psicologia , Pessoas com Deficiência Mental/psicologia , Psicometria/normas , Qualidade de Vida/psicologia , Autorrelato/normas , Adulto , Feminino , Humanos , Masculino , Psicometria/instrumentação , Reprodutibilidade dos Testes
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