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1.
mBio ; 14(5): e0174223, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37707056

RESUMO

IMPORTANCE: Our findings define a novel role for ZIKV-induced TTP expression in regulating IFNß/IFNλ production in primary hBMECs and Sertoli cells. These cells comprise key physiological barriers subverted by ZIKV to access brain and testicular compartments and serve as reservoirs for persistent replication and dissemination. We demonstrate for the first time that the ARE-binding protein TTP is virally induced and post-transcriptionally regulates IFNß/IFNλ secretion. In ZIKV-infected hBMEC and Sertoli cells, TTP knockout increased IFNß/IFNλ secretion, while TTP expression blocked IFNß/IFNλ secretion. The TTP-directed blockade of IFN secretion permits ZIKV spread and persistence in hBMECs and Sertoli cells and may similarly augment ZIKV spread across IFNλ-protected placental barriers. Our work highlights the importance of post-transcriptional ZIKV regulation of IFN expression and secretion in cells that regulate viral access to protected compartments and defines a novel mechanism of ZIKV-regulated IFN responses which may facilitate neurovirulence and sexual transmission.


Assuntos
Infecção por Zika virus , Zika virus , Gravidez , Masculino , Feminino , Humanos , Células de Sertoli/metabolismo , Zika virus/fisiologia , Infecção por Zika virus/metabolismo , Tristetraprolina , Placenta/metabolismo , Replicação Viral
2.
mBio ; 14(4): e0138823, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37489888

RESUMO

Powassan virus (POWV) is an emerging tick-borne Flavivirus that causes lethal encephalitis and long-term neurologic damage. Currently, there are no POWV therapeutics, licensed vaccines, or reverse genetics systems for producing infectious POWVs from recombinant DNA. Using a circular polymerase extension reaction (CPER), we generated recombinant LI9 (recLI9) POWVs with attenuating NS1 protein mutations and a recLI9-split-eGFP reporter virus. NS1 proteins are highly conserved glycoproteins that regulate replication, spread, and neurovirulence. POWV NS1 contains three putative N-linked glycosylation sites that we modified individually in infectious recLI9 mutants (N85Q, N208Q, and N224Q). NS1 glycosylation site mutations reduced replication kinetics and were attenuated, with 1-2 log decreases in titer. Severely attenuated recLI9-N224Q exhibited a 2- to 3-day delay in focal cell-to-cell spread and reduced NS1 secretion but was lethal when intracranially inoculated into suckling mice. However, footpad inoculation of recLI9-N224Q resulted in the survival of 80% of mice and demonstrated that NS1-N224Q mutations reduce POWV neuroinvasion in vivo. To monitor NS1 trafficking, we CPER fused a split GFP11-tag to the NS1 C-terminus and generated an infectious reporter virus, recLI9-NS1-GFP11. Cells infected with recLI9-NS1-GFP11 revealed NS1 trafficking in live cells and the novel formation of large NS1-lined intracellular vesicles. An infectious recLI9-NS1-GFP11 reporter virus permits real-time analysis of NS1 functions in POWV replication, assembly, and secretion and provides a platform for evaluating antiviral compounds. Collectively, our robust POWV reverse genetics system permits analysis of viral spread and neurovirulence determinants in vitro and in vivo and enables the rational genetic design of live attenuated POWV vaccines. IMPORTANCE Our findings newly establish a mechanism for genetically modifying Powassan viruses (POWVs), systematically defining pathogenic determinants and rationally designing live attenuated POWV vaccines. This initial study demonstrates that mutating POWV NS1 glycosylation sites attenuates POWV spread and neurovirulence in vitro and in vivo. Our findings validate a robust circular polymerase extension reaction approach as a mechanism for developing, and evaluating, attenuated genetically modified POWVs. We further designed an infectious GFP-tagged reporter POWV that permits us to monitor secretory trafficking of POWV in live cells, which can be applied to screen potential POWV replication inhibitors. This robust system for modifying POWVs provides the ability to define attenuating POWV mutations and create genetically attenuated recPOWV vaccines.


Assuntos
Doenças Transmissíveis , Vírus da Encefalite Transmitidos por Carrapatos , Humanos , Glicosilação , Genética Reversa , Pele
3.
Methods Mol Biol ; 2409: 197-205, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34709643

RESUMO

A growing body of evidence demonstrates that endothelial cells (ECs) play a prominent role in immune-enhanced pathology seen in dengue virus (DENV) infection that might contribute to vascular permeability and hemorrhagic manifestations in severe dengue cases. However, it remains a question of whether DENV infection of ECs directly causes permeability or if extra-endothelial factors such as immune cell activation or antibody-dependent enhancement (ADE) are required. In this chapter, we detail the measurement of the transendothelial electrical resistance (TEER), a quantitative technique to measure the integrity of tight junction dynamics in cell culture models of endothelial monolayers and show that DENV infection of ECs does not cause endothelial permeability in vitro.


Assuntos
Vírus da Dengue , Dengue , Permeabilidade Capilar , Impedância Elétrica , Células Endoteliais , Humanos
4.
J Virol ; 96(1): e0168221, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34643436

RESUMO

Powassan viruses (POWVs) are neurovirulent tick-borne flaviviruses emerging in the northeastern United States, with a 2% prevalence in Long Island (LI) deer ticks (Ixodes scapularis). POWVs are transmitted within as little as 15 min of a tick bite and enter the central nervous system (CNS) to cause encephalitis (10% of cases are fatal) and long-term neuronal damage. POWV-LI9 and POWV-LI41 present in LI Ixodes ticks were isolated by directly inoculating VeroE6 cells with tick homogenates and detecting POWV-infected cells by immunoperoxidase staining. Inoculated POWV-LI9 and LI41 were exclusively present in infected cell foci, indicative of cell to cell spread, despite growth in liquid culture without an overlay. Cloning and sequencing establish POWV-LI9 as a phylogenetically distinct lineage II POWV strain circulating in LI deer ticks. Primary human brain microvascular endothelial cells (hBMECs) and pericytes form a neurovascular complex that restricts entry into the CNS. We found that POWV-LI9 and -LI41 and lineage I POWV-LB productively infect hBMECs and pericytes and that POWVs were basolaterally transmitted from hBMECs to lower-chamber pericytes without permeabilizing polarized hBMECs. Synchronous POWV-LI9 infection of hBMECs and pericytes induced proinflammatory chemokines, interferon-ß (IFN-ß) and proteins of the IFN-stimulated gene family (ISGs), with delayed IFN-ß secretion by infected pericytes. IFN inhibited POWV infection, but despite IFN secretion, a subset of POWV-infected hBMECs and pericytes remained persistently infected. These findings suggest a potential mechanism for POWVs (LI9/LI41 and LB) to infect hBMECs, spread basolaterally to pericytes, and enter the CNS. hBMEC and pericyte responses to POWV infection suggest a role for immunopathology in POWV neurovirulence and potential therapeutic targets for preventing POWV spread to neuronal compartments. IMPORTANCE We isolated POWVs from LI deer ticks (I. scapularis) directly in VeroE6 cells, and sequencing revealed POWV-LI9 as a distinct lineage II POWV strain. Remarkably, inoculation of VeroE6 cells with POWV-containing tick homogenates resulted in infected cell foci in liquid culture, consistent with cell-to-cell spread. POWV-LI9 and -LI41 and lineage I POWV-LB strains infected hBMECs and pericytes that comprise neurovascular complexes. POWVs were nonlytically transmitted basolaterally from infected hBMECs to lower-chamber pericytes, suggesting a mechanism for POWV transmission across the blood-brain barrier (BBB). POWV-LI9 elicited inflammatory responses from infected hBMEC and pericytes that may contribute to immune cell recruitment and neuropathogenesis. This study reveals a potential mechanism for POWVs to enter the CNS by infecting hBMECs and spreading basolaterally to abluminal pericytes. Our findings reveal that POWV-LI9 persists in cells that form a neurovascular complex spanning the BBB and suggest potential therapeutic targets for preventing POWV spread to neuronal compartments.


Assuntos
Vetores de Doenças , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Encefalite Transmitida por Carrapatos/virologia , Ixodes/virologia , Animais , Células Cultivadas , Vírus da Encefalite Transmitidos por Carrapatos/classificação , Vírus da Encefalite Transmitidos por Carrapatos/efeitos dos fármacos , Vírus da Encefalite Transmitidos por Carrapatos/isolamento & purificação , Encefalite Transmitida por Carrapatos/imunologia , Encefalite Transmitida por Carrapatos/transmissão , Células Endoteliais , Ordem dos Genes , Genoma Viral , Interações Hospedeiro-Patógeno/imunologia , Humanos , Interferons/farmacologia , Pericitos/virologia , Filogenia , Replicação Viral/efeitos dos fármacos
5.
mBio ; 12(4): e0196221, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34399621

RESUMO

Zika virus (ZIKV) is a neurovirulent flavivirus that uniquely causes fetal microcephaly, is sexually transmitted, and persists in patients for up to 6 months. ZIKV persistently infects human brain microvascular endothelial cells (hBMECs) that form the blood-brain barrier (BBB) and enables viral spread to neuronal compartments. We found that CCL5, a chemokine with prosurvival effects on immune cells, was highly secreted by ZIKV-infected hBMECs. Although roles for CCL5 in endothelial cell (EC) survival remain unknown, the presence of the CCL5 receptors CCR3 and CCR5 on ECs suggested that CCL5 could promote ZIKV persistence in hBMECs. We found that exogenous CCL5 induced extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation in hBMECs and that ERK1/2 cell survival signaling was similarly activated by ZIKV infection. Neutralizing antibodies to CCL5, CCR3, or CCR5 inhibited persistent ZIKV infection of hBMECs. While knockout (KO) of CCL5 failed to prevent ZIKV infection of hBMECs, at 3 days postinfection (dpi), we observed a >90% reduction in ZIKV-infected CCL5-KO hBMECs and a multilog reduction in ZIKV titers. In contrast, the addition of CCL5 to CCL5-KO hBMECs dose-dependently rescued ZIKV persistence in hBMECs. Inhibiting CCL5 responses using CCR3 (UCB35625) and CCR5 (maraviroc) receptor antagonists reduced the number of ZIKV-infected hBMECs and ZIKV titers (50% inhibitory concentrations [IC50s] of 2.5 to 12 µM), without cytotoxicity (50% cytotoxic concentration [CC50] of >80 µM). These findings demonstrate that ZIKV-induced CCL5 directs autocrine CCR3/CCR5 activation of ERK1/2 survival responses that are required for ZIKV to persistently infect hBMECs. Our results establish roles for CCL5 in ZIKV persistence and suggest the potential for CCL5 receptor antagonists to therapeutically inhibit ZIKV spread and neurovirulence. IMPORTANCE Our findings demonstrate that CCL5 is required for ZIKV to persistently infect human brain ECs that normally protect neuronal compartments. We demonstrate that ZIKV-elicited CCL5 secretion directs autocrine hBMEC activation of ERK1/2 survival pathways via CCR3/CCR5, and inhibiting CCL5/CCR3/CCR5 responses prevented ZIKV persistence and spread. Our findings demonstrate that ZIKV-directed CCL5 secretion promotes hBMEC survival and reveals an underlying mechanism of ZIKV pathogenesis and spread. We demonstrate that antagonists of CCR3/CCR5 inhibit ZIKV persistence in hBMECs and provide potential therapeutic approaches for preventing ZIKV persistence, spread, and neurovirulence.


Assuntos
Encéfalo/virologia , Quimiocina CCL5/genética , Células Endoteliais/virologia , Zika virus/genética , Zika virus/fisiologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/virologia , Encéfalo/citologia , Células Cultivadas , Quimiocina CCL5/imunologia , Quimiocina CCL5/farmacologia , Células Endoteliais/efeitos dos fármacos , Técnicas de Inativação de Genes , Humanos , Receptores CCR3/metabolismo , Receptores CCR5/metabolismo , Zika virus/efeitos dos fármacos , Zika virus/imunologia
6.
mBio ; 11(6)2020 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-33310781

RESUMO

SARS-CoV-2 causes COVID-19, an acute respiratory distress syndrome (ARDS) characterized by pulmonary edema, viral pneumonia, multiorgan dysfunction, coagulopathy, and inflammation. SARS-CoV-2 uses angiotensin-converting enzyme 2 (ACE2) receptors to infect and damage ciliated epithelial cells in the upper respiratory tract. In alveoli, gas exchange occurs across an epithelial-endothelial barrier that ties respiration to endothelial cell (EC) regulation of edema, coagulation, and inflammation. How SARS-CoV-2 dysregulates vascular functions to cause ARDS in COVID-19 patients remains an enigma focused on dysregulated EC responses. Whether SARS-CoV-2 directly or indirectly affects functions of the endothelium remains to be resolved and is critical to understanding SARS-CoV-2 pathogenesis and therapeutic targets. We demonstrate that primary human ECs lack ACE2 receptors at protein and RNA levels and that SARS-CoV-2 is incapable of directly infecting ECs derived from pulmonary, cardiac, brain, umbilical vein, or kidney tissues. In contrast, pulmonary ECs transduced with recombinant ACE2 receptors are infected by SARS-CoV-2 and result in high viral titers (∼1 × 107/ml), multinucleate syncytia, and EC lysis. SARS-CoV-2 infection of ACE2-expressing ECs elicits procoagulative and inflammatory responses observed in COVID-19 patients. The inability of SARS-CoV-2 to directly infect and lyse ECs without ACE2 expression explains the lack of vascular hemorrhage in COVID-19 patients and indicates that the endothelium is not a primary target of SARS-CoV-2 infection. These findings are consistent with SARS-CoV-2 indirectly activating EC programs that regulate thrombosis and endotheliitis in COVID-19 patients and focus strategies on therapeutically targeting epithelial and inflammatory responses that activate the endothelium or initiate limited ACE2-independent EC infection.IMPORTANCE SARS-CoV-2 infects pulmonary epithelial cells through ACE2 receptors and causes ARDS. COVID-19 causes progressive respiratory failure resulting from diffuse alveolar damage and systemic coagulopathy, thrombosis, and capillary inflammation that tie alveolar responses to EC dysfunction. This has prompted theories that SARS-CoV-2 directly infects ECs through ACE2 receptors, yet SARS-CoV-2 antigen has not been colocalized with ECs and prior studies indicate that ACE2 colocalizes with alveolar epithelial cells and vascular smooth muscle cells, not ECs. Here, we demonstrate that primary human ECs derived from lung, kidney, heart, brain, and umbilical veins require expression of recombinant ACE2 receptors in order to be infected by SARS-CoV-2. However, SARS-CoV-2 lytically infects ACE2-ECs and elicits procoagulative and inflammatory responses observed in COVID-19 patients. These findings suggest a novel mechanism of COVID-19 pathogenesis resulting from indirect EC activation, or infection of a small subset of ECs by an ACE2-independent mechanism, that transforms rationales and targets for therapeutic intervention.


Assuntos
Fatores de Coagulação Sanguínea , Células Endoteliais/virologia , Inflamação , Peptidil Dipeptidase A/genética , SARS-CoV-2/patogenicidade , Animais , Células Cultivadas , Chlorocebus aethiops , Células Endoteliais/imunologia , Células Endoteliais/patologia , Humanos , Proteínas Recombinantes , Células Vero
7.
Acta fisiátrica ; 27(4): 213-219, dez. 2020.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1224482

RESUMO

Objective: To analyze meaning in life, satisfaction with life, and the influence of sociodemographic variables in Brazilians with Spinal Cord Injury (SCI). This was a quantitative, cross-sectional, and descriptive study. Participants: Adults with traumatic SCI. Methods: The data were collected through the Survey Monkey platform using the Meaning in Life Questionnaire and the Satisfaction With Life Scale; the sample was composed of adults 18 years old or older with Traumatic SCI. Results: Most of the participants were male (75.5%), with a mean age of 36.22. The average score on the Satisfaction With Life Scale was 21.26, which corresponds to the Slightly satisfied category. The mean scores, respectively, for search and presence of meaning in life were 22.61 and 25.32, indicating that most participants find life meaningful even though they don't explicitly search for meaning. There were significant associations between satisfaction with life and the meaning in life. Conclusion: In the rehabilitation process for people with Traumatic SCI, the assessment of satisfaction and the meaning of life must be managed together along with other psychological variables. Considering the complex life context of people suffering from a Traumatic SCI, there is a need for both holistic and individualized understanding during the rehabilitation process


Objetivo: Analisar o sentido da vida, a satisfação com a vida e a influência de variáveis sociodemográficas em brasileiros com Lesão Medular Traumática. Trata-se de um estudo quantitativo, transversal e descritivo com participantes adultos com LM traumática. Método: Os dados foram coletados por meio da plataforma Survey Monkey, utilizando o Questionário de Sentido da Vida e a Escala de Satisfação com a Vida; a amostra foi composta por adultos de 18 anos ou mais com LM traumática. Resultados: A maioria dos participantes era do sexo masculino (75,5%), com média de idade de 36,22 anos. A pontuação média na Escala de Satisfação com a Vida foi de 21,26, o que corresponde à categoria pouco satisfeito. As pontuações médias, respectivamente, para busca e presença de sentido na vida foram 22,61 e 25,32, indicando que a maioria dos participantes acha a vida com sentido, embora não busque esse sentido explicitamente. Houve associações significativas entre satisfação com a vida e o sentido da vida. Conclusão: O processo de reabilitação de pessoas com LM traumática deve conter a avaliação da satisfação e do sentido de vida em conjunto com outras variáveis psicológicas. O contexto de vida das pessoas que sofrem de uma LM traumática é complexo e há uma necessidade de compreensão holística e individualizada durante o processo de reabilitação

8.
J Virol ; 94(19)2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32699085

RESUMO

Zika virus (ZIKV) is cytopathic to neurons and persistently infects brain microvascular endothelial cells (hBMECs), which normally restrict viral access to neurons. Despite replicating in the cytoplasm, ZIKV and Dengue virus (DENV) polymerases, NS5 proteins, are predominantly trafficked to the nucleus. We found that a SUMO interaction motif in ZIKV and DENV NS5 proteins directs nuclear localization. However, ZIKV NS5 formed discrete punctate nuclear bodies (NBs), while DENV NS5 was uniformly dispersed in the nucleoplasm. Yet, mutating one DENV NS5 SUMO site (K546R) localized the NS5 mutant to discrete NBs, and NBs formed by the ZIKV NS5 SUMO mutant (K252R) were restructured into discrete protein complexes. In hBMECs, NBs formed by STAT2 and promyelocytic leukemia (PML) protein are present constitutively and enhance innate immunity. During ZIKV infection or NS5 expression, we found that ZIKV NS5 evicts PML from STAT2 NBs, forming NS5/STAT2 NBs that dramatically reduce PML expression in hBMECs and inhibit the transcription of interferon-stimulated genes (ISG). Expressing the ZIKV NS5 SUMO site mutant (K252R) resulted in NS5/STAT2/PML NBs that failed to degrade PML, reduce STAT2 expression, or inhibit ISG induction. Additionally, the K252 SUMOylation site and NS5 nuclear localization were required for ZIKV NS5 to regulate hBMEC cell cycle transcriptional responses. Our data reveal NS5 SUMO motifs as novel NB coordinating factors that distinguish flavivirus NS5 proteins. These findings establish SUMOylation of ZIKV NS5 as critical in the regulation of antiviral ISG and cell cycle responses that permit ZIKV to persistently infect hBMECs.IMPORTANCE ZIKV is a unique neurovirulent flavivirus that persistently infects human brain microvascular endothelial cells (hBMECs), the primary barrier that restricts viral access to neuronal compartments. Here, we demonstrate that flavivirus-specific SIM and SUMO sites determine the assembly of NS5 proteins into discrete nuclear bodies (NBs). We found that NS5 SIM sites are required for NS5 nuclear localization and that SUMO sites regulate NS5 NB complex constituents, assembly, and function. We reveal that ZIKV NS5 SUMO sites direct NS5 binding to STAT2, disrupt the formation of antiviral PML-STAT2 NBs, and direct PML degradation. ZIKV NS5 SUMO sites also transcriptionally regulate cell cycle and ISG responses that permit ZIKV to persistently infect hBMECs. Our findings demonstrate the function of SUMO sites in ZIKV NS5 NB formation and their importance in regulating nuclear responses that permit ZIKV to persistently infect hBMECs and thereby gain access to neurons.


Assuntos
Encéfalo/metabolismo , Núcleo Celular/metabolismo , Células Endoteliais/metabolismo , Sumoilação/fisiologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Zika virus/genética , Zika virus/metabolismo , Células A549 , Antivirais/farmacologia , Sítios de Ligação , Encéfalo/virologia , Ciclo Celular , Células Endoteliais/virologia , Exorribonucleases/metabolismo , Regulação Viral da Expressão Gênica , Células HEK293 , Células HeLa , Humanos , Imunidade Inata/efeitos dos fármacos , Modelos Moleculares , Mutação , Proteína da Leucemia Promielocítica/metabolismo , Fator de Transcrição STAT2/metabolismo , Alinhamento de Sequência , Sumoilação/efeitos dos fármacos , Zika virus/imunologia , Infecção por Zika virus/imunologia , Infecção por Zika virus/metabolismo
9.
J Wound Ostomy Continence Nurs ; 46(4): 321-326, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31274863

RESUMO

PURPOSE: The purpose of this study was to evaluate bladder self-management in transition to adult care for patients with spina bifida (SB) in 3 countries with similar clinical practice and different social, cultural, and economic milieu. STUDY DESIGN: Cross-sectional study. SUBJECTS AND SETTING: The sample comprised 90 participants: 27 reside in Brazil, 36 reside in Germany, and 27 reside in the United States. Demographic characteristics of the sample are based on country. The distribution of sex in the Brazilian sample was 18 males and 9 females, the German group had 11 males and 25 females, and the United States group had 8 males and 19 females. The age range of the cumulative sample was 13 to 29 years. The age of the German sample (mean 23.56, standard deviation [SD] 4.60 years) was significantly higher (analysis of variance, F(2, 87) = 13.62, P < .001) than the other 2 groups (Brazil mean 20.56 years, SD 5.24; US mean 19.44 years, SD 4.70). METHODS: Demographic, clinical, and social variable data were collected via an online questionnaire distributed to multiple regions of Germany and a multidisciplinary myelomeningocele clinic at the University of Michigan in the Midwestern United States. In Brazil, participants completed a printed version of the survey. In Germany and the United States, an electronic version of the survey was made available online. German and English versions of the survey, originally developed in Portuguese for persons residing in Brazil, were translated and validated. RESULTS: The majority of participants (94.4%) performed intermittent catheterization (IC), 76.5% performed IC independently, whereas 23.5% required assistance with IC or catheterized with aids (handles, leg spreaders, and penis or labia holder). There were no statistically significant group differences in independent self-catheterization by gender. There were significant national group differences in level of lesion (P = .016), use of shunt (P = .012), and medication for bladder management (P < .001). Among participants 18 years and older, there were significantly higher levels of education in the German and the US samples than in the Brazilian sample (P < .001). CONCLUSIONS: Although there were national group differences in medical characteristics and management of SB, differences in independent self-catheterization were not significant. Findings suggest that support from family/caregivers and health care providers appears to facilitate transition to independent self-care, regardless of national context.


Assuntos
Transferência de Pacientes/métodos , Autogestão/métodos , Disrafismo Espinal/complicações , Bexiga Urinária/fisiopatologia , Adolescente , Adulto , Análise de Variância , Brasil , Estudos Transversais , Feminino , Alemanha , Humanos , Cateterismo Uretral Intermitente/métodos , Cateterismo Uretral Intermitente/tendências , Masculino , Michigan , Transferência de Pacientes/tendências , Autogestão/tendências , Disrafismo Espinal/psicologia , Estatísticas não Paramétricas , Inquéritos e Questionários
10.
mBio ; 9(5)2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30377280

RESUMO

Misincorporation of uracil or spontaneous cytidine deamination is a common mutagenic insult to DNA. Herpesviruses encode a viral uracil-DNA glycosylase (vUNG) and a viral dUTPase (vDUT), each with enzymatic and nonenzymatic functions. However, the coordinated roles of these enzymatic activities in gammaherpesvirus pathogenesis and viral genomic stability have not been defined. In addition, potential compensation by the host UNG has not been examined in vivo The genetic tractability of the murine gammaherpesvirus 68 (MHV68) system enabled us to delineate the contribution of host and viral factors that prevent uracilated DNA. Recombinant MHV68 lacking vUNG (ORF46.stop) was not further impaired for acute replication in the lungs of UNG-/- mice compared to wild-type (WT) mice, indicating host UNG does not compensate for the absence of vUNG. Next, we investigated the separate and combinatorial consequences of mutating the catalytic residues of the vUNG (ORF46.CM) and vDUT (ORF54.CM). ORF46.CM was not impaired for replication, while ORF54.CM had a slight transient defect in replication in the lungs. However, disabling both vUNG and vDUT led to a significant defect in acute expansion in the lungs, followed by impaired establishment of latency in the splenic reservoir. Upon serial passage of the ORF46.CM/ORF54.CM mutant in either fibroblasts or the lungs of mice, we noted rapid loss of the nonessential yellow fluorescent protein (YFP) reporter gene from the viral genome, due to recombination at repetitive elements. Taken together, our data indicate that the vUNG and vDUT coordinate to promote viral genomic stability and enable viral expansion prior to colonization of latent reservoirs.IMPORTANCE Unrepaired uracils in DNA can lead to mutations and compromise genomic stability. Herpesviruses have hijacked host processes of DNA repair and nucleotide metabolism by encoding a viral UNG that excises uracils and a viral dUTPase that initiates conversion of dUTP to dTTP. To better understand the impact of these processes on gammaherpesvirus pathogenesis, we examined the separate and collaborative roles of vUNG and vDUT upon MHV68 infection of mice. Simultaneous disruption of the enzymatic activities of both vUNG and vDUT led to a severe defect in acute replication and establishment of latency, while also revealing a novel, combinatorial function in promoting viral genomic stability. We propose that herpesviruses require these enzymatic processes to protect the viral genome from damage, possibly triggered by misincorporated uracil. This reveals a novel point of therapeutic intervention to potentially block viral replication and reduce the fitness of multiple herpesviruses.


Assuntos
Deleção de Genes , Instabilidade Genômica , Pirofosfatases/metabolismo , Recombinação Genética , Rhadinovirus/enzimologia , Rhadinovirus/patogenicidade , Uracila-DNA Glicosidase/metabolismo , Animais , Genoma Viral , Infecções por Herpesviridae/veterinária , Infecções por Herpesviridae/virologia , Pulmão/virologia , Camundongos , Pirofosfatases/genética , Rhadinovirus/genética , Doenças dos Roedores/virologia , Uracila-DNA Glicosidase/genética , Virulência
11.
Rehabil Psychol ; 62(3): 268-275, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28836807

RESUMO

PURPOSE/OBJECTIVE: This study was conducted to examine the associations between generic and condition-specific health self-management and levels of adaptive behavior in 2 groups of transition-age youth with congenital neurodevelopmental conditions. METHOD: The sample included 43 adolescents/young adults diagnosed with cerebral palsy (CP) and 36 with spina bifida/myelomeningocele (SBM), ages 13-29, mean age 18.96 (4.77), 51.9% female. Health self-management was assessed with the Transition Readiness Assessment Questionnaire (TRAQ) completed by the child, and the Kennedy Krieger Independence Scales-Spina Bifida (KKIS-SB) completed by the parent/guardian. The Adaptive Behavior Assessment System (ABAS-II) completed by the parent/guardian was used to assess levels of adaptive behavior. RESULTS: There were significant group differences in condition-specific health self-management, including lower KKIS-SB Initiation of Routines and KKIS-SB Prospective Memory scores in the group with SBM. Those differences were no longer significant when scoring was modified to account for item applicability. Group differences in generic health self-management and adaptive behavior were not significant. There were significant differences in the correlations between health self-management instruments and ABAS-II composite scores. CONCLUSIONS: For youth with congenital neurodevelopmental conditions who are in the transition to adulthood, there are important condition-specific self-management needs that are not captured by measuring generic transition readiness or adaptive behavior. Findings highlight the need for clinicians to assess health self-management needs from multiple perspectives, utilizing generic and condition-specific measures that can inform targeted interventions and supports for optimal independence. (PsycINFO Database Record


Assuntos
Adaptação Psicológica , Paralisia Cerebral/psicologia , Meningomielocele/psicologia , Autogestão/psicologia , Autogestão/estatística & dados numéricos , Transição para Assistência do Adulto/estatística & dados numéricos , Adolescente , Adulto , Paralisia Cerebral/reabilitação , Feminino , Humanos , Masculino , Meningomielocele/reabilitação , Autogestão/métodos , Inquéritos e Questionários , Adulto Jovem
12.
Rehabil Psychol ; 62(3): 258-267, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28569523

RESUMO

PURPOSE/OBJECTIVE: To examine mastery motivation and executive functions or behaviors as predictors of adaptive behavior in adolescents and young adults with congenital neurodevelopmental conditions. METHOD: Participants were 2 groups of adolescents and young adults, ages 13-29, including 43 with cerebral palsy and 36 with myelomeningocele living with a parent or caregiver. Participants completed measures of mastery motivation, executive functions or behaviors, and a measure of adaptive behavior. RESULTS: Group differences in mastery motivation, executive functions and executive behaviors, and adaptive behavior profiles were not significant. Mastery motivation, executive functions, and executive behaviors explained a significant portion of variance in adaptive behavior. CONCLUSIONS: Findings highlight the importance of assessing and addressing motivational and executive needs in developing interventions to promote independence. Findings also suggest the need for more comprehensive assessment of adaptive behaviors that include the ability to self-direct others in the completion of tasks necessary for successful daily functioning. (PsycINFO Database Record


Assuntos
Adaptação Psicológica/fisiologia , Paralisia Cerebral/psicologia , Função Executiva/fisiologia , Meningomielocele/psicologia , Motivação/fisiologia , Adolescente , Adulto , Paralisia Cerebral/fisiopatologia , Paralisia Cerebral/reabilitação , Feminino , Humanos , Masculino , Meningomielocele/fisiopatologia , Meningomielocele/reabilitação , Inquéritos e Questionários , Adulto Jovem
13.
J Exp Biol ; 209(Pt 9): 1725-36, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16621953

RESUMO

Bats (Chiroptera) are generally awkward crawlers, but the common vampire bat (Desmodus rotundus) and the New Zealand short-tailed bat (Mystacina tuberculata) have independently evolved the ability to manoeuvre well on the ground. In this study we describe the kinematics of locomotion in both species, and the kinetics of locomotion in M. tuberculata. We sought to determine whether these bats move terrestrially the way other quadrupeds do, or whether they possess altogether different patterns of movement on the ground than are observed in quadrupeds that do not fly. Using high-speed video analyses of bats moving on a treadmill, we observed that both species possess symmetrical lateral-sequence gaits similar to the kinematically defined walks of a broad range of tetrapods. At high speeds, D. rotundus use an asymmetrical bounding gait that appears to converge on the bounding gaits of small terrestrial mammals, but with the roles of the forelimbs and hindlimbs reversed. This gait was not performed by M. tuberculata. Many animals that possess a single kinematic gait shift with increasing speed from a kinetic walk (where kinetic and potential energy of the centre of mass oscillate out of phase from each other) to a kinetic run (where they oscillate in phase). To determine whether the single kinematic gait of M. tuberculata meets the kinetic definition of a walk, a run, or a gait that functions as a walk at low speed and a run at high speed, we used force plates and high-speed video recordings to characterize the energetics of the centre of mass in that species. Although oscillations in kinetic and potential energy were of similar magnitudes, M. tuberculata did not use pendulum-like exchanges of energy between them to the extent that many other quadrupedal animals do, and did not transition from a kinetic walk to kinetic run with increasing speed. The gait of M. tuberculata is kinematically a walk, but kinetically run-like at all speeds.


Assuntos
Quirópteros/fisiologia , Corrida/fisiologia , Caminhada/fisiologia , Animais , Comportamento Animal , Evolução Biológica , Metabolismo Energético/fisiologia , Feminino , Masculino , Especificidade da Espécie
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