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1.
Immun Ageing ; 21(1): 39, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907247

RESUMO

BACKGROUND: Age > 65 years is a key risk factor for poor outcomes after human influenza infection. Specifically, in addition to respiratory disease, non-neurotropic influenza A virus (IAV) causes neuro-cognitive complications, e.g. new onset depression and increases the risk of dementia after hospitalization. This study aimed to identify potential mechanisms of these effects by determining differences between young and old mice in brain gene expression in a mouse model of non-neurotropic IAV infection. METHODS: Young (12 weeks) and old (70 weeks) C57Bl/6J mice were inoculated intranasally with 200 PFU H1N1 A/PR/34/8 (PR8) or sterile PBS (mock). Gene expression in lung and brain was measured by qRT-PCR and normalized to ß-actin. Findings were confirmed using the nCounter Mouse Neuroinflammation Array (NanoString) and analyzed with nSolver 4.0 and Ingenuity Pathway Analysis (IPA, Qiagen). RESULTS: IAV PR8 did not invade the central nervous system. Young and old mice differed significantly in brain gene expression at baseline and during non-neurotropic IAV infection. Expression of brain Ifnl, Irf7, and Tnf mRNAs was upregulated over baseline control at 3 days post-infection (p.i.) only in young mice, but old mice expressed more Ifnl than young mice 7 days p.i. Gene arrays showed down-regulation of the Epigenetic Regulation, Insulin Signaling, and Neurons and Neurotransmission pathways in old mice 3 days p.i. while young mice demonstrated no change or induction of these pathways at the same time point. IPA revealed marked baseline differences between old and young mice. Gene expression related to Cognitive Impairment, Memory Deficits and Learning worsened in old mice relative to young mice during IAV infection. Aged mice demonstrate more severe changes in gene expression related to memory loss and cognitive dysfunction by IPA. CONCLUSIONS: These data suggest the genes and pathways related to learning and cognitive performance that were worse at baseline in old mice were further worsened by IAV infection, similar to old patients. Early events in the brain triggered by IAV infection portend downstream neurocognitive pathology in old adults.

2.
Microb Pathog ; 183: 106305, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37586464

RESUMO

Inhalation anthrax, the deadliest form of the disease, requires inhaled B. anthracis spores to escape from the alveolar space and travel to the mediastinal lymph nodes, from where the vegetative form of the pathogen disseminates, resulting in a rapidly fatal outcome. The role of epithelia in alveolar escape is unclear, but previous work suggests these epithelial cells are involved in this process. Using confocal microscopy, we found that B. anthracis spores are internalized more rapidly by A549 type II alveolar epithelial cells compared to hAELVi type I alveolar epithelial cells. Internalization of spores by alveolar epithelial cells requires cytoskeletal rearrangement evidenced by significant inhibition by cytochalasin D, an actin inhibitor. Chemical inhibitors of macropinocytosis significantly downregulated B. anthracis spore internalization in human alveolar cells, while inhibitors of other endocytosis pathways had minimal effects. Additional studies using a macropinosome marker and electron microscopy confirmed the role of macropinocytosis in spore uptake. By colocalization of B. anthracis spores with four endocytic Rab proteins, we demonstrated that Rab31 played a role in B. anthracis spore macropinocytosis. Finally, we confirmed that Rab31 is involved in B. anthracis spore internalization by enhanced spore uptake in Rab31-overexpressing A549 cells. This is the first report that shows B. anthracis spore internalization by macropinocytosis in human epithelial cells. Several Rab GTPases are involved in the process.


Assuntos
Antraz , Bacillus anthracis , Humanos , Esporos Bacterianos/metabolismo , Células Epiteliais , Pulmão , Antraz/metabolismo
3.
Proc Biol Sci ; 288(1953): 20211141, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34157869

RESUMO

Coastal marine systems are characterized by high levels of primary production that result in diel oxygen fluctuations from undersaturation to supersaturation. Constant normoxia, or 100% oxygen saturation, is therefore rare. Since the thermal sensitivity of invertebrates is directly linked to oxygen availability, we hypothesized that (i) the metabolic response of coastal marine invertebrates would be more sensitive to thermal stress when exposed to oxygen supersaturation rather than 100% oxygen saturation and (ii) natural diel fluctuation in oxygen availability rather than constant 100% oxygen saturation is a main driver of the thermal response. We tested the effects of oxygen regime on the metabolic rate, and haemocyanin and lactate levels, of velvet crabs (Necora puber) and blue mussels (Mytilus edulis), under rising temperatures (up to 24°C) in the laboratory. Oxygen supersaturation and photosynthetically induced diel oxygen fluctuation amplified animal metabolic thermal response significantly in both species, demonstrating that the natural variability of oxygen in coastal environments can provide considerable physiological benefits under ocean warming. Our study highlights the significance of integrating ecologically relevant oxygen variability into experimental assessments of animal physiology and thermal response, and predictions of metabolic performance under climate warming. Given the escalating intensity and frequency of climate anomalies, oxygen variation caused by coastal vegetation will likely become increasingly important in mitigating the effects of higher temperatures on coastal fauna.


Assuntos
Organismos Aquáticos , Oxigênio , Animais , Mudança Climática , Temperatura Alta , Invertebrados , Temperatura
4.
J Antimicrob Chemother ; 76(9): 2464-2471, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-34109397

RESUMO

BACKGROUND: Understanding antimicrobial consumption is essential to mitigate the development of antimicrobial resistance, yet robust data in children are sparse and methodologically limited. Electronic prescribing systems provide an important opportunity to analyse and report antimicrobial consumption in detail. OBJECTIVES: We investigated the value of electronic prescribing data from a tertiary children's hospital to report temporal trends in antimicrobial consumption in hospitalized children and compare commonly used metrics of antimicrobial consumption. METHODS: Daily measures of antimicrobial consumption [days of therapy (DOT) and DDDs] were derived from the electronic prescribing system between 2010 and 2018. Autoregressive moving-average models were used to infer trends and the estimates were compared with simulated point prevalence surveys (PPSs). RESULTS: More than 1.3 million antimicrobial administrations were analysed. There was significant daily and seasonal variation in overall consumption, which reduced annually by 1.77% (95% CI 0.50% to 3.02%). Relative consumption of meropenem decreased by 6.6% annually (95% CI -3.5% to 15.8%) following the expansion of the hospital antimicrobial stewardship programme. DOT and DDDs exhibited similar trends for most antimicrobials, though inconsistencies were observed where changes to dosage guidelines altered consumption calculation by DDDs, but not DOT. PPS simulations resulted in estimates of change over time, which converged on the model estimates, but with much less precision. CONCLUSIONS: Electronic prescribing systems offer significant opportunities to better understand and report antimicrobial consumption in children. This approach to modelling administration data overcomes the limitations of using interval data and dispensary data. It provides substantially more detailed inferences on prescribing patterns and the potential impact of stewardship interventions.


Assuntos
Anti-Infecciosos , Gestão de Antimicrobianos , Prescrição Eletrônica , Antibacterianos/uso terapêutico , Criança , Criança Hospitalizada , Humanos
5.
Respir Res ; 22(1): 112, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879121

RESUMO

BACKGROUND: Influenza is a highly contagious, acute, febrile respiratory infection caused by a negative-sense, single-stranded RNA virus, which belongs in the Orthomyxoviridae family. Cigarette smoke (CS) exposure worsens influenza infection in terms of frequency and severity in both human and animal models. METHODS: C57BL/6 mice with or without CS exposure for 6 weeks were inoculated intranasally with a single, non-lethal dose of the influenza A virus (IAV) A/Puerto Rico/8/1934 (PR8) strain. At 7 and 10 days after infection, lung and mediastinal lymph nodes (MLN) cells were collected to determine the numbers of total CD4 + and CD8 + T cells, and IAV-specific CD4 + and CD8 + T cells, using flow cytometry. Bronchoalveolar lavage fluid (BALF) was also collected to determine IFN-γ levels and total protein concentration. RESULTS: Although long-term CS exposure suppressed early pulmonary IAV-antigen specific CD8 + and CD4 + T cell numbers and IFN-γ production in response to IAV infection on day 7 post-infection, CS enhanced numbers of these cells and IFN-γ production on day 10. The changes of total protein concentration in BALF are consistent with the changes in the IFN-γ amounts between day 7 and 10, which suggested that excessive IFN-γ impaired barrier function and caused lung injury at the later stage of infection. CONCLUSIONS: Our results demonstrated that prior CS exposure caused a biphasic T cell and IFN-γ response to subsequent infection with influenza in the lung. Specifically, the number of IAV antigen-specific T cells on day 10 was greatly increased by CS exposure even though CS decreased the number of the same group of cells on day 7. The result suggested that CS affected the kinetics of the T cell response to IAV, which was suppressed at an early stage and exaggerated at a later stage. This study is the first to describe the different effect of long-term CS on T cell responses to IAV at early and late stages of infection in vivo.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Interferon gama/metabolismo , Pulmão/imunologia , Ativação Linfocitária , Infecções por Orthomyxoviridae/imunologia , Fumaça/efeitos adversos , Linfócitos T/imunologia , Produtos do Tabaco/toxicidade , Animais , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Patógeno , Vírus da Influenza A Subtipo H1N1/patogenicidade , Pulmão/metabolismo , Pulmão/virologia , Masculino , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Linfócitos T/metabolismo , Linfócitos T/virologia , Fatores de Tempo
6.
Gynecol Oncol ; 156(2): 288-292, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31767189

RESUMO

OBJECTIVES: The objective of this quality improvement (QI) project was to decrease the rate of low-value computed tomography (CT) imaging in established gynecologic oncology patients presenting to the emergency department (ED). METHODS: This was a cohort study with a before and after design that evaluated implementation of a QI project designed to decrease CT utilization in established gynecologic oncology patients in the ED. The pre-intervention cohort included patients admitted through the ED from 4/1/17 to 5/31/18, while the post-intervention cohort was from 6/1/18 to 5/31/19. The intervention included gynecologic oncology consultation before CT on patients who had imaging within the prior 3 weeks. Details regarding CT, ED length of stay (LOS), and oncologic history were abstracted. The value of CT was determined by consensus from 2 reviewers. Prospective data monitoring evaluated for patient safety. RESULTS: Prior to intervention, there were 129 unique ED encounters in gynecologic oncology patients leading to admission. CT scans were performed in 101 (78.3%) encounters, 57.7% of which were deemed to be of low-value. Following implementation, the CT utilization rate decreased significantly from median monthly rate of 75.2% to 49.1% (p < 0.00001), and the ED LOS decreased from 8.1 to 6.9 h (p = 0.0102). The number of CT scans deemed to be low-value in the post-intervention group decreased to 2 (3.8%). CONCLUSIONS: Implementation of an early consultation policy and imaging guidelines led to a significant decrease in unnecessary CT utilization and shorter ED LOS in gynecologic oncology patients presenting to the ED.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Neoplasias dos Genitais Femininos/diagnóstico por imagem , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Estudos de Coortes , Serviço Hospitalar de Emergência/normas , Feminino , Neoplasias dos Genitais Femininos/terapia , Fidelidade a Diretrizes , Humanos , Pessoa de Meia-Idade , Melhoria de Qualidade , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas
7.
J Nat Prod ; 83(10): 2877-2893, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33000946

RESUMO

Phytocannabinoids are a group of plant-derived metabolites that display a wide range of psychoactive as well as health-promoting effects. The production of pharmaceutically relevant cannabinoids relies on extraction and purification from cannabis (Cannabis sativa) plants yielding the major constituents, Δ9-tetrahydrocannabinol and cannabidiol. Heterologous biosynthesis of cannabinoids in Nicotiana benthamiana or Saccharomyces cerevisiae may provide cost-efficient and rapid future production platforms to acquire pure and high quantities of both the major and the rare cannabinoids as well as novel derivatives. Here, we used a meta-transcriptomic analysis of cannabis to identify genes for aromatic prenyltransferases of the UbiA superfamily and chalcone isomerase-like (CHIL) proteins. Among the aromatic prenyltransferases, CsaPT4 showed CBGAS activity in both N. benthamiana and S. cerevisiae. Coexpression of selected CsaPT pairs and of CHIL proteins encoding genes with CsaPT4 did not affect CBGAS catalytic efficiency. In a screen of different plant UDP-glycosyltransferases, Stevia rebaudiana SrUGT71E1 and Oryza sativa OsUGT5 were found to glucosylate olivetolic acid, cannabigerolic acid, and Δ9-tetrahydrocannabinolic acid. Metabolic engineering of N. benthamiana for production of cannabinoids revealed intrinsic glucosylation of olivetolic acid and cannabigerolic acid. S. cerevisiae was engineered to produce olivetolic acid glucoside and cannabigerolic acid glucoside.


Assuntos
Canabinoides/metabolismo , Glucosídeos/metabolismo , Nicotiana/fisiologia , Saccharomyces cerevisiae/fisiologia , Canabidiol , Cannabis , Dronabinol , Engenharia Metabólica , Estrutura Molecular , Proteínas de Plantas , Salicilatos , Biologia Sintética
8.
J Immunol ; 198(3): 1183-1201, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28031342

RESUMO

The respiratory system is a complex network of many cell types, including subsets of macrophages and dendritic cells that work together to maintain steady-state respiration. Owing to limitations in acquiring cells from healthy human lung, these subsets remain poorly characterized transcriptionally and phenotypically. We set out to systematically identify these subsets in human airways by developing a schema of isolating large numbers of cells by whole-lung bronchoalveolar lavage. Six subsets of phagocytic APC (HLA-DR+) were consistently observed. Aside from alveolar macrophages, subsets of Langerin+, BDCA1-CD14+, BDCA1+CD14+, BDCA1+CD14-, and BDCA1-CD14- cells were identified. These subsets varied in their ability to internalize Escherichia coli, Staphylococcus aureus, and Bacillus anthracis particles. All subsets were more efficient at internalizing S. aureus and B. anthracis compared with E. coli Alveolar macrophages and CD14+ cells were overall more efficient at particle internalization compared with the four other populations. Subsets were further separated into two groups based on their inherent capacities to upregulate surface CD83, CD86, and CCR7 expression levels. Whole-genome transcriptional profiling revealed a clade of "true dendritic cells" consisting of Langerin+, BDCA1+CD14+, and BDCA1+CD14- cells. The dendritic cell clade was distinct from a macrophage/monocyte clade, as supported by higher mRNA expression levels of several dendritic cell-associated genes, including CD1, FLT3, CX3CR1, and CCR6 Each clade, and each member of both clades, was discerned by specific upregulated genes, which can serve as markers for future studies in healthy and diseased states.


Assuntos
Células Dendríticas/fisiologia , Pulmão/imunologia , Macrófagos Alveolares/fisiologia , Macrófagos/fisiologia , Adulto , Idoso , Antígenos CD/análise , Antígenos CD1/análise , Antígeno B7-2/análise , Células Dendríticas/classificação , Perfilação da Expressão Gênica , Glicoproteínas/análise , Humanos , Imunoglobulinas/análise , Receptores de Lipopolissacarídeos/análise , Pulmão/microbiologia , Macrófagos/classificação , Glicoproteínas de Membrana/análise , Pessoa de Meia-Idade , Antígeno CD83
9.
Microb Pathog ; 121: 9-21, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29704667

RESUMO

The lung is the entry site for Bacillus anthracis in inhalation anthrax, the most deadly form of the disease. Spores must escape through the alveolar epithelial cell (AEC) barrier and migrate to regional lymph nodes, germinate and enter the circulatory system to cause disease. Several mechanisms to explain alveolar escape have been postulated, and all these tacitly involve the AEC barrier. In this study, we incorporate our primary human type I AEC model, microarray and gene enrichment analysis, qRT-PCR, multiplex ELISA, and neutrophil and monocyte chemotaxis assays to study the response of AEC to B. anthracis, (Sterne) spores at 4 and 24 h post-exposure. Spore exposure altered gene expression in AEC after 4 and 24 h and differentially expressed genes (±1.3 fold, p ≤ 0.05) included CCL4/MIP-1ß (4 h), CXCL8/IL-8 (4 and 24 h) and CXCL5/ENA-78 (24 h). Gene enrichment analysis revealed that pathways involving cytokine or chemokine activity, receptor binding, and innate immune responses to infection were prominent. Microarray results were confirmed by qRT-PCR and multiplex ELISA assays. Chemotaxis assays demonstrated that spores induced the release of biologically active neutrophil and monocyte chemokines, and that CXCL8/IL-8 was the major neutrophil chemokine. The small or sub-chemotactic doses of CXCL5/ENA-78, CXCL2/GROß and CCL20/MIP-3α may contribute to chemotaxis by priming effects. These data provide the first whole transcriptomic description of the human type I AEC initial response to B. anthracis spore exposure. Taken together, our findings contribute to an increased understanding of the role of AEC in the pathogenesis of inhalational anthrax.


Assuntos
Células Epiteliais Alveolares/microbiologia , Bacillus anthracis/patogenicidade , Quimiocinas/metabolismo , Perfilação da Expressão Gênica , Esporos Bacterianos/patogenicidade , Antraz/genética , Antraz/metabolismo , Quimiocina CCL20/genética , Quimiocina CCL20/metabolismo , Quimiocina CXCL5/genética , Quimiocina CXCL5/metabolismo , Quimiocinas/genética , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Monócitos/metabolismo , Monócitos/microbiologia , Neutrófilos/metabolismo , Neutrófilos/microbiologia , Fator Plaquetário 4/genética , Fator Plaquetário 4/metabolismo , Infecções Respiratórias/genética , Infecções Respiratórias/metabolismo , Regulação para Cima
10.
Haemophilia ; 24(3): 376-384, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29732708

RESUMO

INTRODUCTION: Currently, no universally accepted definition of extended half-life (EHL) recombinant FVIII (rFVIII) exists. Identifying the minimum half-life extension ratio required for a reduction in dosing frequency compared with standard rFVIII could enable a more practical approach to decisions around prophylaxis with EHL rFVIII. AIM: To identify the half-life extension ratio required to decrease rFVIII dosing frequency by at least 1 day while maintaining the proportion of patients with plasma rFVIII levels above 1 IU/dL and without increasing the total weekly dose. METHODS: A previously published population pharmacokinetic model for standard rFVIII was used to estimate the percentage of patients with factor VIII (FVIII) levels always >1 IU/dL using various benchmark regimens. Using modelling, dosing frequency was reduced while rFVIII half-life was extended until the percentage of patients with FVIII >1 IU/dL equalled that of the benchmark regimen. RESULTS: Benchmark 3×/wk dosing totalling 100 IU/kg/wk of rFVIII resulted in 56.6% of patients with FVIII levels always >1 IU/dL. With 2×/wk dosing, totalling 80 or 90 IU/kg/wk, half-life extensions required to maintain 56.6% of patients at FVIII levels >1 IU/dL were 1.30 and 1.26, respectively. A half-life extension ratio of 1.33 was required to change dosing from every 48 hours to every 72 hours (both at 105 IU/kg/wk) while maintaining 92.8% of patients with FVIII >1 IU/dL. CONCLUSION: Based on this investigation, EHL rFVIII products should have a minimum half-life extension ratio of 1.3 to provide a reduction in dosing frequency from 3× to 2×/wk compared with standard rFVIII products while maintaining the same minimum FVIII trough level.


Assuntos
Fator VIII/administração & dosagem , Fator VIII/farmacocinética , Modelos Biológicos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacocinética , Relação Dose-Resposta a Droga , Fator VIII/uso terapêutico , Meia-Vida , Hemofilia A/tratamento farmacológico , Humanos , Proteínas Recombinantes/uso terapêutico
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