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1.
Nat Commun ; 15(1): 4605, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816388

RESUMO

Obesity-induced inflammation causes metabolic dysfunction, but the mechanisms remain elusive. Here we show that the innate immune transcription factor interferon regulatory factor (IRF3) adversely affects glucose homeostasis through induction of the endogenous FAHFA hydrolase androgen induced gene 1 (AIG1) in adipocytes. Adipocyte-specific knockout of IRF3 protects male mice against high-fat diet-induced insulin resistance, whereas overexpression of IRF3 or AIG1 in adipocytes promotes insulin resistance on a high-fat diet. Furthermore, pharmacological inhibition of AIG1 reversed obesity-induced insulin resistance and restored glucose homeostasis in the setting of adipocyte IRF3 overexpression. We, therefore, identify the adipocyte IRF3/AIG1 axis as a crucial link between obesity-induced inflammation and insulin resistance and suggest an approach for limiting the metabolic dysfunction accompanying obesity.


Assuntos
Adipócitos , Dieta Hiperlipídica , Inflamação , Resistência à Insulina , Fator Regulador 3 de Interferon , Camundongos Knockout , Obesidade , Animais , Fator Regulador 3 de Interferon/metabolismo , Fator Regulador 3 de Interferon/genética , Masculino , Obesidade/metabolismo , Camundongos , Dieta Hiperlipídica/efeitos adversos , Inflamação/metabolismo , Adipócitos/metabolismo , Camundongos Endogâmicos C57BL , Glucose/metabolismo , Células 3T3-L1
2.
Int J Clin Pharm ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38734867

RESUMO

BACKGROUND: Medication errors significantly compromise patient safety in emergency departments. Although previous studies have investigated the prevalence of these errors in this setting, results have varied widely. AIM: The aim was to report pooled data on the prevalence and severity of medication errors in emergency departments, as well as the proportion of patients affected by these errors. METHOD: Systematic searches were conducted in Embase, PubMed, and the Cochrane Library from database inception until June 2023. Studies provided numerical data on medication errors within emergency departments were eligible for inclusion. Random-effects meta-analysis was employed to pool the prevalence of medication errors, the proportion of patients experiencing these errors, and the error severity levels. Heterogeneity among studies was assessed using the I2 statistic and Cochran's Q test. RESULTS: Twenty-four studies met the inclusion criteria. The meta-analysis gave a pooled prevalence of medication errors in emergency departments of 22.6% (95% Confidence Interval [CI] 19.2-25.9%, I2 = 99.9%, p < 0.001). The estimated proportion of patients experiencing medication errors was 36.3% (95% CI 28.3-44.3%, I2 = 99.8%, p < 0.001). Of these errors, 42.6% (95% CI 5.0-80.1%) were potentially harmful but not life-threatening, while no-harm errors accounted for 57.3% (95% CI 14.1-100.0%). CONCLUSION: The prevalence of medication errors, particularly those potentially harmful, underscores potential safety issues in emergency departments. It is imperative to develop and implement effective interventions aimed at reducing medication errors and enhancing patient safety in this setting.

3.
BMC Genom Data ; 24(1): 54, 2023 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-37735352

RESUMO

BACKGROUND: Cells orchestrate histone biogenesis with strict temporal and quantitative control. To efficiently regulate histone biogenesis, the repetitive Drosophila melanogaster replication-dependent histone genes are arrayed and clustered at a single locus. Regulatory factors concentrate in a nuclear body known as the histone locus body (HLB), which forms around the locus. Historically, HLB factors are largely discovered by chance, and few are known to interact directly with DNA. It is therefore unclear how the histone genes are specifically targeted for unique and coordinated regulation. RESULTS: To expand the list of known HLB factors, we performed a candidate-based screen by mapping 30 publicly available ChIP datasets of 27 unique factors to the Drosophila histone gene array. We identified novel transcription factor candidates, including the Drosophila Hox proteins Ultrabithorax (Ubx), Abdominal-A (Abd-A), and Abdominal-B (Abd-B), suggesting a new pathway for these factors in influencing body plan morphogenesis. Additionally, we identified six other factors that target the histone gene array: JIL-1, hormone-like receptor 78 (Hr78), the long isoform of female sterile homeotic (1) (fs(1)h) as well as the general transcription factors TBP associated factor 1 (TAF-1), Transcription Factor IIB (TFIIB), and Transcription Factor IIF (TFIIF). CONCLUSIONS: Our foundational screen provides several candidates for future studies into factors that may influence histone biogenesis. Further, our study emphasizes the powerful reservoir of publicly available datasets, which can be mined as a primary screening technique.


Assuntos
Proteínas de Drosophila , Infertilidade , Feminino , Animais , Drosophila , Drosophila melanogaster/genética , Histonas/genética , Montagem e Desmontagem da Cromatina/genética , Biologia Computacional , Proteínas de Drosophila/genética , Fatores de Transcrição/genética , Proteínas de Homeodomínio/genética , Proteínas Serina-Treonina Quinases
4.
Front Glob Womens Health ; 4: 1180383, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37389285

RESUMO

Introduction: Breast cancer remains one of the major cancers worldwide. In Asia, breast cancer is leading both incidence and mortality rates. Health-related quality of life (HRQoL) studies play an important role in clinical treatment. This systematic review aimed to summarize the evidence of HRQoL and associated factors among patients with breast cancer in low-and-middle-income countries (LMICs) in Asia. Method: Performed according to PRISMA guidelines for systematic review, the studies were searched from three databases (PubMed, Cochrane, Scopus) up to November 2020. The studies which met the predefined eligibility criteria were selected, extracted, and assessed the quality according to the Newcastle-Ottawa Scale (NOS) tool. Results and Discussion: A total of 2,620 studies were searched on the three databases, of which 28 met the selection criteria, then, were included in the systematic review. The Global Health Status (GHS) score of breast cancer patients based on the EORTC QLQ-C30 questionnaire ranged from 56.32 ± 25.42 to 72.48 ± 15.68. The overall HRQoL scores using the FACT-G and FACT-B instruments ranged from 60.78 ± 13.27 to 82.23 ± 12.55 and from 70.29 ± 13.33 to 108.48 ± 19.82, respectively. Factors affecting HRQoL of patients with breast cancer included age, education level, income, marital status, lifestyle, tumor stage, method, and treatment duration. Patient's income showed a consistent effect on HRQoL while the remaining factors reported inconsistent findings across the studies. In conclusion, the HRQoL of breast cancer patients in LMICs in Asia was low and affected by several sociodemographic factors which should be studied more in future research.

5.
Nat Chem Biol ; 19(12): 1469-1479, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37349583

RESUMO

Serine hydrolases have important roles in signaling and human metabolism, yet little is known about their functions in gut commensal bacteria. Using bioinformatics and chemoproteomics, we identify serine hydrolases in the gut commensal Bacteroides thetaiotaomicron that are specific to the Bacteroidetes phylum. Two are predicted homologs of the human dipeptidyl peptidase 4 (hDPP4), a key enzyme that regulates insulin signaling. Our functional studies reveal that BT4193 is a true homolog of hDPP4 that can be inhibited by FDA-approved type 2 diabetes medications targeting hDPP4, while the other is a misannotated proline-specific triaminopeptidase. We demonstrate that BT4193 is important for envelope integrity and that loss of BT4193 reduces B. thetaiotaomicron fitness during in vitro growth within a diverse community. However, neither function is dependent on BT4193 proteolytic activity, suggesting a scaffolding or signaling function for this bacterial protease.


Assuntos
Bacteroides thetaiotaomicron , Diabetes Mellitus Tipo 2 , Humanos , Dipeptidil Peptidase 4/genética , Serina
6.
Am J Infect Control ; 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37257565

RESUMO

Hospital onset Clostridioides difficile infection (CDI) causes significant disease burden and is associated with increased patient mortality. A nurse-driven CDI test order set had been implemented to reduce hospital-onset CDI, yet the order set was not being used. We employed a humble inquiry interview method to identify barriers to using the CDI test order set. The humble inquiry approach uncovered unexpected barriers and may be a robust method to identify additional infection prevention evidence-to-practice gaps.

7.
Nat Chem Biol ; 17(8): 856-864, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33927411

RESUMO

Multiple Ras proteins, including N-Ras, depend on a palmitoylation/depalmitoylation cycle to regulate their subcellular trafficking and oncogenicity. General lipase inhibitors such as Palmostatin M (Palm M) block N-Ras depalmitoylation, but lack specificity and target several enzymes displaying depalmitoylase activity. Here, we describe ABD957, a potent and selective covalent inhibitor of the ABHD17 family of depalmitoylases, and show that this compound impairs N-Ras depalmitoylation in human acute myeloid leukemia (AML) cells. ABD957 produced partial effects on N-Ras palmitoylation compared with Palm M, but was much more selective across the proteome, reflecting a plasma membrane-delineated action on dynamically palmitoylated proteins. Finally, ABD957 impaired N-Ras signaling and the growth of NRAS-mutant AML cells in a manner that synergizes with MAP kinase kinase (MEK) inhibition. Our findings uncover a surprisingly restricted role for ABHD17 enzymes as regulators of the N-Ras palmitoylation cycle and suggest that ABHD17 inhibitors may have value as targeted therapies for NRAS-mutant cancers.


Assuntos
Membrana Celular/metabolismo , Hidrolases/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Promielocítica Aguda/metabolismo , Proteínas ras/metabolismo , Proliferação de Células , Células Cultivadas , Humanos , Leucemia Mieloide Aguda/patologia , Leucemia Promielocítica Aguda/patologia , Lipoilação , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Estrutura Molecular
8.
Front Cell Infect Microbiol ; 11: 752899, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34976853

RESUMO

The continued proliferation of superbugs in hospitals and the coronavirus disease 2019 (COVID-19) has created an acute worldwide demand for sustained broadband pathogen suppression in households, hospitals, and public spaces. In response, we have created a highly active, self-sterilizing copper configuration capable of inactivating a wide range of bacteria and viruses in 30-60 seconds. The highly active material destroys pathogens faster than any conventional copper configuration and acts as quickly as alcohol wipes and hand sanitizers. Unlike the latter, our copper material does not release volatile compounds or leave harmful chemical residues and maintains its antimicrobial efficacy over sustained use; it is shelf stable for years. We have performed rigorous testing in accordance with guidelines from U.S. regulatory agencies and believe that the material could offer broad spectrum, non-selective defense against most microbes via integration into masks, protective equipment, and various forms of surface coatings.


Assuntos
Anti-Infecciosos , COVID-19 , Antibacterianos , Humanos , Equipamento de Proteção Individual , SARS-CoV-2
9.
Cell Rep ; 31(12): 107805, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32579931

RESUMO

In the adult ventricular-subventricular zone (V-SVZ), neural stem cells (NSCs) generate new olfactory bulb (OB) neurons and glia throughout life. To map adult neuronal lineage progression, we profiled >56,000 V-SVZ and OB cells by single-cell RNA sequencing (scRNA-seq). Our analyses reveal the molecular diversity of OB neurons, including fate-mapped neurons, lineage progression dynamics, and an NSC intermediate enriched for Notum, which encodes a secreted WNT antagonist. SCOPE-seq technology, which links live-cell imaging with scRNA-seq, uncovers cell-size transitions during NSC differentiation and preferential NOTUM binding to proliferating neuronal precursors. Consistently, application of NOTUM protein in slice cultures and pharmacological inhibition of NOTUM in slice cultures and in vivo demonstrated that NOTUM negatively regulates V-SVZ proliferation. Timely, context-dependent neurogenesis demands adaptive signaling among neighboring progenitors. Our findings highlight a critical regulatory state during NSC activation marked by NOTUM, which attenuates WNT-stimulated proliferation in NSC progeny.


Assuntos
Envelhecimento/metabolismo , Linhagem da Célula , Esterases/metabolismo , Ventrículos Laterais/citologia , Neurogênese , Análise de Célula Única , Animais , Proliferação de Células , Regulação da Expressão Gênica , Genes Reporter , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Bulbo Olfatório/citologia
10.
J Virol ; 94(12)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32269122

RESUMO

Early and robust T cell responses have been associated with survival from Lassa fever (LF), but the Lassa virus-specific memory responses have not been well characterized. Regions within the virus surface glycoprotein (GPC) and nucleoprotein (NP) are the main targets of the Lassa virus-specific T cell responses, but, to date, only a few T cell epitopes within these proteins have been identified. We identified GPC and NP regions containing T cell epitopes and HLA haplotypes from LF survivors and used predictive HLA-binding algorithms to identify putative epitopes, which were then experimentally tested using autologous survivor samples. We identified 12 CD8-positive (CD8+) T cell epitopes, including epitopes common to both Nigerian and Sierra Leonean survivors. These data should be useful for the identification of dominant Lassa virus-specific T cell responses in Lassa fever survivors and vaccinated individuals as well as for designing vaccines that elicit cell-mediated immunity.IMPORTANCE The high morbidity and mortality associated with clinical cases of Lassa fever, together with the lack of licensed vaccines and limited and partially effective interventions, make Lassa virus (LASV) an important health concern in its regions of endemicity in West Africa. Previous infection with LASV protects from disease after subsequent exposure, providing a framework for designing vaccines to elicit similar protective immunity. Multiple major lineages of LASV circulate in West Africa, and therefore, ideal vaccine candidates should elicit immunity to all lineages. We therefore sought to identify common T cell epitopes between Lassa fever survivors from Sierra Leone and Nigeria, where distinct lineages circulate. We identified three such epitopes derived from highly conserved regions within LASV proteins. In this process, we also identified nine other T cell epitopes. These data should help in the design of an effective pan-LASV vaccine.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/química , Febre Lassa/imunologia , Vírus Lassa/imunologia , Nucleoproteínas/imunologia , Proteínas do Envelope Viral/imunologia , Adolescente , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/biossíntese , Antígenos Virais/química , Antígenos Virais/genética , Antígenos Virais/imunologia , Linfócitos T CD8-Positivos/virologia , Criança , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Feminino , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/imunologia , Antígenos HLA-DQ/genética , Antígenos HLA-DQ/imunologia , Haplótipos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Soros Imunes/análise , Memória Imunológica , Febre Lassa/genética , Febre Lassa/patologia , Vírus Lassa/patogenicidade , Masculino , Nigéria , Nucleoproteínas/genética , Serra Leoa , Sobreviventes , Proteínas do Envelope Viral/genética , Adulto Jovem
11.
PLoS Pathog ; 16(3): e1008352, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32142546

RESUMO

Lassa virus infects hundreds of thousands of people each year across rural West Africa, resulting in a high number of cases of Lassa fever (LF), a febrile disease associated with high morbidity and significant mortality. The lack of approved treatments or interventions underscores the need for an effective vaccine. At least four viral lineages circulate in defined regions throughout West Africa with substantial interlineage nucleotide and amino acid diversity. An effective vaccine should be designed to elicit Lassa virus specific humoral and cell mediated immunity across all lineages. Most current vaccine candidates use only lineage IV antigens encoded by Lassa viruses circulating around Sierra Leone, Liberia, and Guinea but not Nigeria where lineages I-III are found. As previous infection is known to protect against disease from subsequent exposure, we sought to determine whether LF survivors from Nigeria and Sierra Leone harbor memory T cells that respond to lineage IV antigens. Our results indicate a high degree of cross-reactivity of CD8+ T cells from Nigerian LF survivors to lineage IV antigens. In addition, we identified regions within the Lassa virus glycoprotein complex and nucleoprotein that contributed to these responses while T cell epitopes were not widely conserved across our study group. These data are important for current efforts to design effective and efficient vaccine candidates that can elicit protective immunity across all Lassa virus lineages.


Assuntos
Antígenos Virais/imunologia , Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Vírus Lassa/imunologia , África Ocidental , Reações Cruzadas , Feminino , Humanos , Masculino , Especificidade da Espécie
12.
J Biol Chem ; 295(18): 5891-5905, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32152231

RESUMO

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a newly discovered class of signaling lipids with anti-inflammatory and anti-diabetic properties. However, the endogenous regulation of FAHFAs remains a pressing but unanswered question. Here, using MS-based FAHFA hydrolysis assays, LC-MS-based lipidomics analyses, and activity-based protein profiling, we found that androgen-induced gene 1 (AIG1) and androgen-dependent TFPI-regulating protein (ADTRP), two threonine hydrolases, control FAHFA levels in vivo in both genetic and pharmacologic mouse models. Tissues from mice lacking ADTRP (Adtrp-KO), or both AIG1 and ADTRP (DKO) had higher concentrations of FAHFAs particularly isomers with the ester bond at the 9th carbon due to decreased FAHFA hydrolysis activity. The levels of other lipid classes were unaltered indicating that AIG1 and ADTRP specifically hydrolyze FAHFAs. Complementing these genetic studies, we also identified a dual AIG1/ADTRP inhibitor, ABD-110207, which is active in vivo Acute treatment of WT mice with ABD-110207 resulted in elevated FAHFA levels, further supporting the notion that AIG1 and ADTRP activity control endogenous FAHFA levels. However, loss of AIG1/ADTRP did not mimic the changes associated with pharmacologically administered FAHFAs on extent of upregulation of FAHFA levels, glucose tolerance, or insulin sensitivity in mice, indicating that therapeutic strategies should weigh more on FAHFA administration. Together, these findings identify AIG1 and ADTRP as the first endogenous FAHFA hydrolases identified and provide critical genetic and chemical tools for further characterization of these enzymes and endogenous FAHFAs to unravel their physiological functions and roles in health and disease.


Assuntos
Esterases/metabolismo , Ésteres/química , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Proteínas de Membrana/metabolismo , Animais , Esterases/deficiência , Esterases/genética , Técnicas de Inativação de Genes , Hidrólise , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos
13.
SLAS Technol ; 24(5): 489-498, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31199699

RESUMO

Accurate measurement of drug-target interactions in vivo is critical for both preclinical development and translation to clinical studies, yet many assays rely on indirect measures such as biomarkers associated with target activity. Activity-based protein profiling (ABPP) is a direct method of quantifying enzyme activity using active site-targeted small-molecule covalent probes that selectively label active but not inhibitor-bound enzymes. Probe-labeled enzymes in complex proteomes are separated by polyacrylamide gel electrophoresis and quantified by fluorescence imaging. To accelerate workflows and avoid imaging artifacts that make conventional gels challenging to quantify, we adapted protocols for a commercial LabChip GXII microfluidic instrument to permit electrophoretic separation of probe-labeled proteins in tissue lysates and plasma, and quantification of fluorescence (probe/protein labeling ratio of 1:1). Electrophoretic separation on chips occurred in 40 s per sample, and instrument software automatically identified and quantified peaks, resulting in an overall time savings of 3-5 h per 96-well sample plate. Calculated percent inhibition was not significantly different between the two formats. Chip performance was consistent between chips and sample replicates. Conventional gel imaging was more sensitive but required five times higher sample volume than microfluidic chips. Microfluidic chips produced results comparable to those of gels but with much lower sample consumption, facilitating assay miniaturization for scarce biological samples. The time savings afforded by microfluidic electrophoresis and automatic quantification has allowed us to incorporate microfluidic ABPP early in the drug discovery workflow, enabling routine assessments of tissue distribution and engagement of targets and off-targets in vivo.


Assuntos
Microfluídica/métodos , Proteômica/métodos , Algoritmos , Animais , Bioensaio , Camundongos , Peso Molecular , Reprodutibilidade dos Testes
14.
Emotion ; 19(8): 1414-1424, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30475027

RESUMO

Prior studies have found mixed results regarding whether there are cultural differences in the age-related positivity effect, defined as older adults' showing a greater bias in cognitive processing for positively over negatively and neutrally valenced information relative to younger adults. This study attempted to address this controversy by examining visual attention toward culturally relevant versus irrelevant pictures that differed in valence among younger and older U.S. Americans and Hong Kong Chinese. Preferences (attentional biases toward particular valence) and effectiveness (whether the attentional biases are associated with better mood) were also distinguished. Findings revealed that regardless of cultural relevance of the pictures, older U.S. Americans showed more gaze preference for positive over negative pictures compared to their younger counterparts; this age difference was not found among Hong Kong Chinese. In contrast, older Hong Kong Chinese showed better mood as a function of more gaze preference for positive over negative pictures. Younger Hong Kong Chinese and younger and older U.S. Americans did not show this association. The results suggest that an age-related positivity effect exists at the preference level for U.S. Americans but at the effectiveness level for Chinese. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Pesquisa Comparativa da Efetividade/métodos , Emoções/fisiologia , Fatores Etários , Idoso , Cultura , Feminino , Humanos , Masculino , Preferência do Paciente
15.
J Pharmacol Exp Ther ; 367(3): 494-508, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30305428

RESUMO

Monoacylglycerol lipase (MGLL) is the primary degradative enzyme for the endocannabinoid 2-arachidonoylglycerol (2-AG). The first MGLL inhibitors have recently entered clinical development for the treatment of neurologic disorders. To support this clinical path, we report the pharmacological characterization of the highly potent and selective MGLL inhibitor ABD-1970 [1,1,1,3,3,3-hexafluoropropan-2-yl 4-(2-(8-oxa-3-azabicyclo[3.2.1]octan-3-yl)-4-chlorobenzyl)piperazine-1-carboxylate]. We used ABD-1970 to confirm the role of MGLL in human systems and to define the relationship between MGLL target engagement, brain 2-AG concentrations, and efficacy. Because MGLL contributes to arachidonic acid metabolism in a subset of rodent tissues, we further used ABD-1970 to evaluate whether selective MGLL inhibition would affect prostanoid production in several human assays known to be sensitive to cyclooxygenase inhibitors. ABD-1970 robustly elevated brain 2-AG content and displayed antinociceptive and antipruritic activity in a battery of rodent models (ED50 values of 1-2 mg/kg). The antinociceptive effects of ABD-1970 were potentiated when combined with analgesic standards of care and occurred without overt cannabimimetic effects. ABD-1970 also blocked 2-AG hydrolysis in human brain tissue and elevated 2-AG content in human blood without affecting stimulated prostanoid production. These findings support the clinical development of MGLL inhibitors as a differentiated mechanism to treat pain and other neurologic disorders.


Assuntos
Endocanabinoides/metabolismo , Inibidores Enzimáticos/farmacologia , Monoacilglicerol Lipases/antagonistas & inibidores , Analgésicos/farmacologia , Animais , Antipruriginosos/farmacologia , Ácidos Araquidônicos/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Linhagem Celular Tumoral , Inibidores de Ciclo-Oxigenase/farmacologia , Glicerídeos/metabolismo , Humanos , Hidrólise/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Células PC-3 , Dor/tratamento farmacológico , Dor/metabolismo , Piperidinas/farmacologia , Prostaglandinas/farmacologia , Ratos , Ratos Sprague-Dawley , Roedores
17.
J Virol ; 89(23): 12166-77, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26401045

RESUMO

UNLABELLED: Hemorrhagic fever arenaviruses (HFA) pose important public health problems in regions where they are endemic. Thus, Lassa virus (LASV) infects several hundred thousand individuals yearly in West Africa, causing a large number of Lassa fever cases associated with high morbidity and mortality. Concerns about human-pathogenic arenaviruses are exacerbated because of the lack of FDA-licensed arenavirus vaccines and because current antiarenaviral therapy is limited to an off-label use of ribavirin that is only partially effective. The Mopeia virus (MOPV)/LASV reassortant (ML29) is a LASV candidate live-attenuated vaccine (LAV) that has shown promising results in animal models. Nevertheless, the mechanism of ML29 attenuation remains unknown, which raises concerns about the phenotypic stability of ML29 in response to additional mutations. Development of LAVs based on well-defined molecular mechanisms of attenuation will represent a major step in combatting HFA. We used the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) to develop a general molecular strategy for arenavirus attenuation. Our approach involved replacement of the noncoding intergenic region (IGR) of the L genome segment with the IGR of the S genome segment to generate a recombinant LCMV, rLCMV(IGR/S-S), that was highly attenuated in vivo but induced protection against a lethal challenge with wild-type LCMV. Attenuation of rLCMV(IGR/S-S) was associated with a stable reorganization of the control of viral gene expression. This strategy can facilitate the rapid development of LAVs with the antigenic composition of the parental HFA and a mechanism of attenuation that minimizes concerns about increased virulence that could be caused by genetic changes in the LAV. IMPORTANCE: Hemorrhagic fever arenaviruses (HFA) cause high morbidity and mortality, and pose important public health problems in the regions where they are endemic. Implementation of live-attenuated vaccines (LAV) will represent a major step in combatting HFA. Here we have used the prototypic arenavirus LCMV to document a general molecular strategy for arenavirus attenuation that can facilitate the rapid development of safe and effective, as well as stable, LAV to combat HFA.


Assuntos
Arenaviridae/imunologia , Febre Lassa/prevenção & controle , Vacinas Atenuadas/biossíntese , Vacinas Virais/biossíntese , Animais , Arenaviridae/genética , Northern Blotting , Chlorocebus aethiops , Primers do DNA/genética , Humanos , Vírus da Coriomeningite Linfocítica/genética , Plasmídeos/genética , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/genética , Células Vero , Vacinas Virais/imunologia
18.
J Virol ; 89(21): 10924-33, 2015 11.
Artigo em Inglês | MEDLINE | ID: mdl-26292327

RESUMO

UNLABELLED: Several arenaviruses cause hemorrhagic fever disease in humans and represent important public health problems in the regions where these viruses are endemic. In addition, evidence indicates that the worldwide-distributed prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) is an important neglected human pathogen. There are no licensed arenavirus vaccines and current antiarenavirus therapy is limited to the use of ribavirin that is only partially effective. Therefore, there is an unmet need for novel antiarenaviral therapeutics. Here, we report the generation of a novel recombinant LCM virus and its use to develop a cell-based high-throughput screen to rapidly identify inhibitors of LCMV multiplication. We used this novel assay to screen a library of 30,400 small molecules and identified compound F3406 (chemical name: N-[3,5-bis(fluoranyl)phenyl]-2-[5,7-bis(oxidanylidene)-6-propyl-2-pyrrolidin-1-yl-[1,3]thiazolo[4,5-d]pyrimidin-4-yl]ethanamide), which exhibited strong anti-LCMV activity in the absence of cell toxicity. Mechanism-of-action studies revealed that F3406 inhibited LCMV cell entry by specifically interfering with the pH-dependent fusion in the endosome compartment that is mediated by LCMV glycoprotein GP2 and required to release the virus ribonucleoprotein into the cell cytoplasm to initiate transcription and replication of the virus genome. We identified residue M437 within the transmembrane domain of GP2 as critical for virus susceptibility to F3406. IMPORTANCE: Hemorrhagic fever arenaviruses (HFA) are important human pathogens that cause high morbidity and mortality in areas where these viruses are endemic. In addition, evidence indicates that the worldwide-distributed prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) is a neglected human pathogen of clinical significance. Concerns posed by arenavirus infections are aggravated by the lack of U.S. Food and Drug Administration-licensed arenavirus vaccines and current antiarenaviral therapy being limited to the off-label use of ribavirin that is only partially effective. Here we describe a novel recombinant LCMV and its use to develop a cell-based assay suitable for HTS to rapidly identify inhibitors arenavirus multiplication. The concepts and experimental strategies we describe in this work provide the bases for the rapid identification and characterization of novel anti-HFA therapeutics.


Assuntos
Infecções por Arenaviridae/prevenção & controle , Vírus da Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/fisiologia , Pirimidinonas/farmacologia , Bibliotecas de Moléculas Pequenas/química , Tiazóis/farmacologia , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/fisiologia , Animais , Western Blotting , Chlorocebus aethiops , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Plasmídeos/genética , Pirimidinonas/análise , Tiazóis/análise , Células Vero , Replicação Viral/efeitos dos fármacos
19.
Emotion ; 15(3): 292-302, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25985276

RESUMO

Although context is crucial to emotion perception, there are various factors that can modulate contextual influence. The current research investigated how cue type, top-down control, and the perceiver's age influence attention to context in facial emotion perception. In 2 experiments, younger and older adults identified facial expressions contextualized by other faces, isolated objects, and scenes. In the first experiment, participants were instructed to ignore face, object, and scene contexts. Face context was found to influence perception the least, whereas scene context produced the most contextual effect. Older adults were more influenced by context than younger adults, but both age groups were similarly influenced by different types of contextual cues, even when they were instructed to ignore the context. In the second experiment, when explicitly instructed that the context had no meaningful relationship to the target, younger and older adults both were less influenced by context than when they were instructed that the context was relevant to the target. Results from both studies indicate that contextual influence on emotion perception is not constant, but can vary based on the type of contextual cue, cue relevance, and the perceiver's age.


Assuntos
Sinais (Psicologia) , Emoções , Expressão Facial , Percepção/fisiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Atenção/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Adulto Jovem
20.
J Virol ; 89(10): 5734-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25762740

RESUMO

In this study, we document that efficient interaction between arenavirus nucleoprotein (NP) and RNA-dependent RNA polymerase (L protein), the two trans-acting viral factors required for both virus RNA replication and gene transcription, requires the presence of virus-specific RNA sequences located within the untranslated 5' and 3' termini of the viral genome.


Assuntos
Arenavirus/metabolismo , Nucleocapsídeo/metabolismo , Nucleoproteínas/metabolismo , RNA Polimerase Dependente de RNA/metabolismo , Proteínas Virais/metabolismo , Arenavirus/genética , Genoma Viral , Células HEK293 , Humanos , Vírus da Coriomeningite Linfocítica/genética , Vírus da Coriomeningite Linfocítica/fisiologia , Nucleocapsídeo/genética , Nucleoproteínas/genética , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , RNA Polimerase Dependente de RNA/genética , Proteínas Virais/genética , Replicação Viral
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